US20230127868A1 - Antenna Unit for Work Vehicle and Work Vehicle - Google Patents

Abstract

A GNSS antenna and an inertial measurement unit are placed at a longitudinal center of a unit base mountable onto a work vehicle. A wireless communication unit is placed at the longitudinal one end side of the unit base. A wireless communication antenna of the wireless communication unit is placed in a front part of the unit base, which is located on the front side of a vehicle body when the unit base is mounted on the work vehicle. The GNSS antenna is provided above the inertial measurement unit.

Description

TECHNICAL FIELD
• The present invention relates to an antenna unit for a work vehicle used in an automatic traveling system or the like for allowing a work vehicle such as a tractor to automatically travel along a target traveling route while acquiring position information of the work vehicle by using a Global Navigation Satellite System (GNSS), and relates to a work vehicle with a cabin, in particular, a work vehicle suitable in automatic traveling (including self-driving) of the work vehicle such as a tractor along a target traveling route while acquiring position information of the work vehicle by using a Global Navigation Satellite System (GNSS).
BACKGROUND ART
• For example, in a tractor disclosed inPatent Literature 1 as a work vehicle employing an automatic traveling system, a GPS antenna (GNSS antenna) for acquiring satellite positioning information from a positioning satellite is provided on an upper surface of its cabin roof.
• Specifically, on the upper surface of the cabin roof, a mounting stay having a substantially horizontal mounting seat at a higher position than the top surface of the cabin roof is formed in a portion including the intersection of the front-rear direction line at the approximate center of the tread width of the vehicle body and the transverse direction line at the approximate center of the wheel base, and the GPS antenna is mounted on the mounting seat of the mounting stay.
• Further, in a case where, as the GPS antenna, a GPS antenna with a gyro sensor is used, the inclination angle of the cabin roof can be detected.
CITATION LISTPatent Literature
• PTL 1: Japanese Unexamined Patent Application Publication No. 2016-002874
DISCLOSURE OF INVENTIONProblems to be Solved by the Invention
• The above-described conventional technique discloses a technique for improving the detection accuracy of the GPS antenna or the detection accuracy of both the GPS antenna and the gyro sensor by elaborating the mounting position of the GPS antenna on the upper surface of the cabin roof.
• However, the above-described automatic traveling system is provided with various types of external devices separately from the work vehicle, such as a wireless communication terminal that issues various instructions to the work vehicle and a base station that acquires position information of the work vehicle.
• Therefore, when automatic traveling of the work vehicle is actually performed, it is necessary to efficiently mount, on the work vehicle, not only the GPS antenna but also various types of antenna devices for communicating between the work vehicle and external devices. In this respect, the above-described conventional technique has room for improvement.
• In addition, in the above-described conventional technique, the upper surface of the cabin roof provided at the upper part of the cabin frame has many curves and is also less rigid than the cabin frame. Accordingly, it is necessary to reinforce the mounting stay on which the GPS antenna is mounted without impairing the appearance of the cabin roof. Also in this respect, the conventional technique has room for improvement.
• In view of such a situation, a main object of the present invention is to provide an antenna unit for a work vehicle by which various types of antenna devices effective for automatic traveling and the like of the work vehicle can be efficiently installed in the work vehicle.
• Further, a main object of the present invention is to provide a work vehicle capable of mounting various types of antenna devices effective for automatic traveling and the like of the work vehicle and securely supporting various types of antenna devices.
Means for Solving the Problems
• A first characteristic configuration of the present invention is that a GNSS antenna and an inertial measurement unit are placed at a longitudinal center of a unit base mountable onto a work vehicle; a wireless communication unit is placed at one end side in a longitudinal direction of the unit base; a wireless communication antenna of the wireless communication unit is placed in a front part of the unit base, which is located on a front side of a vehicle body when the unit base is mounted on the work vehicle; and the GNSS antenna is provided above the inertial measurement unit.
• Since the GNSS antenna and the inertial measurement unit are placed at the longitudinal center of the unit base mountable on the work vehicle, for example, when the unit base is mounted onto the work vehicle in the left-right direction with satisfactory balance, the longitudinal center of the unit base is placed at the center position in the left-right direction of the work vehicle. This allows the GNSS antenna and the inertial measurement unit to be placed at the center position in the left-right direction of the work vehicle, and accordingly makes it possible to improve both the detection accuracy of the current position information of the work vehicle acquired from a reception signal of the GNSS antenna and the detection accuracy of posture change information of the vehicle body acquired from the inertia measurement unit.
• Further, the wireless communication unit placed on one end side in the longitudinal direction of the unit base enables a wireless communication with an external device such as a wireless communication terminal with various types of signals.
• In addition, since the wireless communication antenna of the wireless communication unit is placed at one end side in the longitudinal direction of the unit base placed apart from the inertial measurement unit, a sufficient distance can be secured between the wireless communication antenna of the wireless communication unit and the center of the inertial measurement unit. Further, since the wireless communication antenna of the wireless communication unit is placed in the front part of the unit base, which is the front side of the vehicle body when the unit base is mounted on the work vehicle, a sufficient distance can be secured in the front-rear direction between a metal component such as the cabin frame of the work vehicle and the wireless communication antenna of the wireless communication unit, in a state where the unit base is mounted on the work vehicle. This suppresses radio interference between the wireless communication unit and the inertial measurement unit, and makes it less susceptible to radio wave shielding by metal components of the work vehicle. Accordingly, it is possible to reduce factors of a communication failure between the wireless communication unit and the wireless communication terminal.
• Therefore, rational elaboration of the installation positions and orientation postures of the GNSS antenna, the inertial measurement unit, and the wireless communication antenna of the wireless communication unit with respect to the unit base as described above makes it possible to improve both the detection accuracy of the inertial measurement unit and the detection accuracy of the GNSS antenna with a reduced size of the antenna unit itself, and allows them to be efficiently installed in the work vehicle with a satisfactory communication of the wireless communication unit maintained.
• A second characteristic configuration of the present invention is that a plurality of the wireless communication antennas are placed in the front part of the unit base and in parallel in the longitudinal direction of the unit base.
• With the above configuration, the plurality of wireless communication antennas of the wireless communication unit make it possible to increase the speed of communication with an external device such as a wireless communication terminal. In addition, since the plurality of wireless communication antennas are placed in parallel in the front part of the unit base and in the longitudinal direction of the unit base, it is less likely for all the wireless communication antennas to be affected by radio wave shielding by a metal component such as the cabin frame of the work vehicle, so that a satisfactory communication of the wireless communication unit can be maintained.
• A third characteristic configuration of the present invention is that a distance between the GNSS antenna and an inner surface of a unit cover configured to cover the unit base is set to 30 mm or more.
• With the above configuration, it is possible to suppress radio interference due to the close proximity between the GNSS antenna and the inner surface of the unit cover, thereby improving the detection accuracy of the current position information of the work vehicle acquired from a reception signal of the GNSS antenna.
• A fourth characteristic configuration of the present invention is that a base station antenna configured to receive information from a reference station is placed on the other end side in the longitudinal direction of the unit base, and a raising part configured to place the base station antenna in a higher place than an antenna mounting part of the unit base is provided between the base station antenna and the antenna mounting part.
• With the above configuration, an upper end part of the base station antenna can be placed in a higher place by the height of the raising part, and thus it is possible to improve the reception performance with respect to the reference station while preventing the base station antenna from breaking due to swinging caused by traveling vibration and the like of the work vehicle, as compared with a case where a long base station antenna is used.
• A fifth characteristic configuration of the present invention is that a mounting space for another unit is formed on the other end side in the longitudinal direction of the unit base.
• With the above configuration, it is possible to easily mount another unit such as a retrofit controller configured to control, for example, a part of the automatic traveling control by using a mounting space secured on the other end side in the longitudinal direction of the unit base. In addition, it is possible to efficiently and compactly store, in the antenna unit, such other unit mounted later.
• A sixth characteristic configuration of the present invention is that, in a work vehicle with a cabin, a support frame extending in a left-right width direction at an upper position outside the cabin is fixed to brackets extending upward from both right and left sides of a cabin frame, and an antenna unit in which an inertial measurement unit, a GNSS antenna, and a wireless communication device are built is built in the support frame in a state where the inertial measurement unit and the GNSS antenna are placed at a substantially center position in a left-right width direction of a vehicle body, and that the antenna unit is configured as an antenna unit for a work vehicle according to the present invention.
• With the above configuration, since the inertial measurement unit and the GNSS antenna which are built in the antenna unit are placed at the substantially center position in the left-right width direction of the vehicle body, it is possible to improve both the detection accuracy of the current position information of the work vehicle acquired from a reception signal of the GNSS antenna and the detection accuracy of the posture change information of the vehicle body acquired from the inertial measurement unit.
• Further, the wireless communication device built in the antenna unit enables a wireless communication with an external device such as a wireless communication terminal with various types of signals.
• In addition, the support frame on which the antenna unit is mounted is mounted on the brackets extending upward from both right and left sides of the cabin frame. In that mounting state, the support frame is fixed to the rigid cabin frame in a posture along the left-right width direction at the upper position outside the cabin. This makes it possible to configure the support frame and both brackets to have a strong support structure integrated with the cabin frame.
• Further, the cabin frame has a height close to the cabin roof, and the brackets extend upward from both left and right sides of the cabin frame. This allows a mounting position of the support frame to be set to an upper side of the cabin frame with a simple support structure, and makes it possible to easily place the antenna unit at a height position where the inertial measurement unit, the GNSS antenna, and the wireless communication device function properly.
• Therefore, the adoption of the antenna unit in which the inertial measurement unit, the GNSS antenna, and the wireless communication device are built, the installation position of the inertial measurement unit and the GNSS antenna with respect to the vehicle body, and the above-described rational elaboration in the support structure of the antenna unit make it possible to improve both the detection accuracy of the inertial measurement unit and the detection accuracy of the GNSS antenna and allow them to be efficiently installed in the work vehicle with a satisfactory communication of the wireless communication device maintained. In addition, it is possible to configure a strong support structure of the installed antenna unit.
• A seventh characteristic configuration of the present invention is that the antenna unit is mounted to be displaceable from a working position to a non-working position on a lower front side with respect to the support frame, and a guide unit configured to guide the antenna unit to be moved in a front-rear direction between the working position and the non-working position is provided.
• With the above configuration, in a state where the antenna unit is in the working position, for example, it is preferable that the antenna unit or the antenna included in the antenna unit is placed to protrude upward from the highest part of the top surface of the cabin roof so that the inertial measurement unit, the GNSS antenna, and the wireless communication device in the antenna unit function properly. However, in this case, the height of a transport vehicle such as a truck to transport the work vehicle is high, and thus, there may be a problem that the vehicle is subject to height restrictions in traveling on a road or the like. Therefore, in the present invention, when the antenna unit from the working position to the non-working position on the lower front side with respect to the support frame, it is possible to easily cope with the problem such as the height restrictions in traveling on a road.
• In addition, since the antenna unit is moved forward along the guide unit when the antenna unit is displaced from the working position to the non-working position, it is possible to place the antenna unit in the non-working position by using a large space in the front upper part of the cabin.
• An eighth characteristic configuration of the present invention is that the antenna unit is mounted to be displaceable from a working position to a non-working position on a lower side with respect to the support frame, and the antenna unit is placed at a position substantially equal to or lower than a highest part of a top surface of the cabin in a state where the antenna unit is displaced to the non-working position on the lower side.
• With the above configuration, in a state where the antenna unit is in the working position, for example, it is preferable that the antenna unit or the antenna included in the antenna unit is placed to protrude upward from the highest part of the top surface of the cabin roof so that the inertial measurement unit, the GNSS antenna, and the wireless communication device in the antenna unit function properly. However, even in this case, since the antenna unit is placed at the position substantially equal to or lower than the highest part of the top surface of the cabin when the antenna unit is displaced to the non-working position, it is possible to easily cope with the problem such as height restrictions in traveling on a road when the work vehicle is transported by a transport vehicle such as a truck.
BRIEF DESCRIPTION OF DRAWINGS
• FIG.1 is an overall side view of a tractor equipped with an antenna unit.
• FIG.2 is a control block diagram of a tractor, a reference station, and a wireless communication terminal.
• FIG.3 is a front view of an antenna unit mounting part of the tractor.
• FIG.4 is a side view of the antenna unit mounting part of the tractor.
• FIG.5 is a perspective view of the antenna unit mounting part of the tractor.
• FIG.6 is a longitudinal sectional view of the antenna unit as viewed from the front.
• FIG.7 is a longitudinal sectional view of the antenna unit as viewed from the rear.
• FIG.8 is a cross-sectional view of the antenna unit as viewed from the right side.
• FIG.9 is a perspective view of the antenna unit with a cover separated.
• FIG.10 is a perspective view of the antenna unit with another unit mounted and the cover removed.
• FIG.11 is a plan view of the antenna unit with the other unit mounted and the cover removed.
• FIG.12 is a side view the antenna unit changed to a non-working position.
• FIG.13A is a side view illustrating a height relationship between the antenna unit in a working position and a highest part of a cabin, andFIG.13B is a side view illustrating a height relationship between the antenna unit in the non-working position and the highest part of the cabin.
• FIG.14 is a perspective view of the cabin at an elevation angle.
• FIG.15 is a perspective view of a main part of the cabin.
• FIG.16 is an exploded side view of an antenna unit mounting part according to another embodiment.
DESCRIPTION OF EMBODIMENTS
• Embodiments of the present invention will be described with reference to the drawings.
• An automatic traveling system illustrated inFIGS.1 and2 uses anantenna unit50 for a work vehicle, and is configured to generate a target traveling route, and enable atractor1 serving as a work vehicle to automatically travel along the generated target traveling route. The automatic traveling system includes, in addition to thetractor1 capable of automatic traveling, awireless communication terminal30 configured to issue various types of instructions to thetractor1 and areference station40 configured to acquire position information of thetractor1.
• First, thetractor1 will be described with reference toFIG.1. Thetractor1 includes avehicle body unit2 configured to mount a ground work machine (not illustrated) on the rear side, a front part of thevehicle body unit2 is supported by a pair of left and rightfront wheels3, and a rear part of thevehicle body unit2 is supported by a pair of left and rightrear wheels4. Ahood5 is placed in the front part of thevehicle body unit2, and anengine6 serving as a drive source is housed inside thehood5. Acabin7 for a driver to ride is provided on the rear side of thehood5, and asteering handle8 for the driver to perform a steering operation, a driver's seat9 for the driver, and the like are provided in thecabin7.
• Theengine6 can be constructed of, for example, a diesel engine, but is not limited to this, and may be constructed of, for example, a gasoline engine. Further, an electric motor may be employed as a drive source in addition to or instead of theengine6.
• Further, in the present embodiment, thetractor1 will be described as a work vehicle by way of example, but examples of the work vehicle include, in addition to the tractor, riding type of work vehicles such as a rice transplanter, a combine, a civil engineering/construction work device, and a snowplow.
• On the rear side of thevehicle body unit2, a three-point link mechanism including a pair of left and rightlower links10 and anupper link11 is provided so that a ground work machine is mountable on the three-point link mechanism. Although not illustrated, on the rear side of thevehicle body unit2, a lifting device including a hydraulic device such as a lifting cylinder is provided, and the lifting device raises and lowers the three-point link mechanism to raises and lowers the ground work machine.
• Examples of the ground work machine include a tilling device, a plow, and a fertilizer applying device.
• As illustrated inFIG.2, thetractor1 includes anengine device21 configured to adjust the rotation speed of theengine6, atransmission device22 configured to change a rotational driving force from theengine6 and transmit the rotational driving force to driving wheels, and acontrol unit23 configured to control theengine device21 and thetransmission device22. Thetransmission device22 is constructed from, for example, a combination of a main transmission device including a hydraulic continuously variable transmission device and an auxiliary transmission device including a gear-type multi-stage transmission device.
• Thetractor1 is configured not only to allow the driver to ride in thecabin7 to travel, but also to allow thetractor1 itself to automatically travel based on, for example, an instruction from thewireless communication terminal30 without a driver riding in thecabin7.
• As illustrated inFIG.2, thetractor1 includes asteering device24, an inertial measurement unit (IMU)25 configured to obtain posture change information of the vehicle body, aGNSS antenna26 configured to receive a radio signal transmitted from a positioning satellite (navigation satellite)45 included in a Global Navigation Satellite System (GNSS), a wireless communication unit (an example of a wireless communication device built in the antenna unit50)27 configured to transmit and receive various types of signals via a wireless communication network established between thewireless communication unit27 and thewireless communication terminal30 and the like, a base station antenna (an example of a wireless communication device built in the antenna unit50)29 configured to receive a wireless signal (e.g., a wireless signal with a frequency band of 920 MHz) from a reference stationwireless communication device41 of thereference station40, and the like. As a result, thetractor1 is configured to automatically travel while acquiring its own current position information (position information of the vehicle body unit2).
• Theinertial measurement unit25, theGNSS antenna26, thewireless communication unit27, and thebase station antenna29 are housed in theantenna unit50 with aunit cover51 as illustrated inFIGS.6 to9. As illustrated inFIGS.3 to5, theantenna unit50 is mounted on asupport frame100, which is fixed to acabin frame200 of thecabin7 and arranged along the left-right width direction, at an upper position on the front side outside thecabin7.
• It is noted that a specific internal arrangement structure and mounting structure of theantenna unit50 will be described in detail after the description of the automatic traveling system.
• Thesteering device24 is provided, for example, in the middle of the rotation shaft of thesteering handle8 and is configured to adjust the rotation angle (steering angle) of thesteering handle8. Thecontrol unit23 controlling thesteering device24 adjusts the rotation angle of the steering handle8 to a desired rotation angle to perform not only straight traveling but also turn traveling with a desired turning radius.
• Theinertial measurement unit25 obtains a three-dimensional angular velocity and an acceleration with a three-dimensional gyro and a three-directional accelerometer. A detection value of theinertial measurement unit25 is input to thecontrol unit23, and thecontrol unit23 operates the value by using a posture and azimuth operation means to calculate posture information (an azimuth angle (yaw angle) of thetractor1, a tilt angle in the left-right direction (roll angle) of the vehicle body of thetractor1, and a tilt angle in the front-rear moving direction (pitch angle) of the vehicle body of thetractor1.
• In the Global Navigation Satellite System (GNSS), as thepositioning satellite45, the GPS (US) may be employed, but a satellite positioning system such as a quasi-zenith satellite (Japan) or a GLONASS satellite (Russia) may also be employed.
• In the present embodiment, thewireless communication unit27 is composed of a Wi-Fi unit with a frequency band of 2.4 GHz, but thewireless communication unit27 may use Bluetooth (registered trademark) other than Wi-fi. As illustrated inFIG.2, a signal received by awireless communication antenna28 of thewireless communication unit27 may be input to thecontrol unit23, and a signal from thecontrol unit23 is configured to be transmitted by thewireless communication antenna28 to awireless communication device31 of thewireless communication terminal30 or the like.
• Here, for a positioning method using the satellite positioning system, a positioning method of obtaining a current position of thetractor1 is applicable, in the positioning method, thereference station40 installed at a predetermined reference point is provided, and correction information from thereference station40 and satellite positioning information of the tractor1 (mobile station) are used. For example, various types of positioning methods such as a differential GPS positioning (DGPS) and a real-time kinematic positioning (RTK positioning) are applicable.
• In the present embodiment, for example, the RTK positioning is applied, and as illustrated inFIGS.1 and2, in addition to including theGNSS antenna26 in thetractor1 being the mobile station side, thereference station40 including a referencestation positioning antenna42 is provided. Thereference station40 is placed at a position (reference point) where the traveling of thetractor1 is not hindered, such as an area around a farm field. Position information of the reference point being an installation position of thereference station40 is obtained in advance. Thereference station40 includes the reference stationwireless communication device41 configured to transmit and receive various types of signals to and from thebase station antenna29 of thetractor1. As a result, thereference station40 is configured to transmit and receive a variety of information to and from thetractor1.
• In the RTK positioning, both the referencestation positioning antenna42 of thereference station40 installed at the reference point and theGNSS antenna26 of thetractor1 being the mobile station side whose position information is to be obtained measure a carrier phase (satellite positioning information) from thepositioning satellite45. Thereference station40 generates correction information including the measured satellite positioning information and the position information of the reference point each time the satellite positioning information is measured from thepositioning satellite45 or each time a set period elapses, and transmits the correction information from the reference stationwireless communication device41 to thebase station antenna29 of thetractor1. Thecontrol unit23 of thetractor1 obtains the current position information of thetractor1 by using the satellite positioning information measured by theGNSS antenna26 and the correction information transmitted from thereference station40. Thecontrol unit23 obtains, for example, latitude information and longitude information as the current position information of thetractor1.
• The automatic traveling system includes, in addition to thetractor1 and thereference station40, thewireless communication terminal30 configured to issue an instruction to cause thetractor1 to automatically travel, to thecontrol unit23 of thetractor1. Thewireless communication terminal30 is composed of, for example, a tablet-type personal computer having a touch panel, is configured to display a variety of information on the touch panel, and also to receive an input of a variety of information through an operation on the touch panel. Thewireless communication terminal30 includes thewireless communication device31 and aroute generation unit32 configured to generate a target traveling route. Theroute generation unit32 generates the target traveling route where thetractor1 automatically travels based on the variety of information input through the touch panel.
• Thecontrol unit23 included in thetractor1 is configured to transmit and receive a variety of information to and from thewireless communication terminal30 via a wireless communication network established with thewireless communication device31 or the like. Thewireless communication terminal30 is configured to issue an instruction for thetractor1 to automatically travel by transmitting a variety of information for causing thetractor1 to automatically travel, such as the target traveling route, to thecontrol unit23 of thetractor1. Thecontrol unit23 of thetractor1 is configured to obtain the current position information of thetractor1 acquired from a reception signal of theGNSS antenna26 so that thetractor1 automatically travels along the target traveling route generated by theroute generation unit32, obtain displacement information and azimuth information of the vehicle body from theinertial measurement unit25, and control thetransmission device22, thesteering device24, and the like based on the current position information, the displacement information, and the azimuth information.
• Next, an internal arrangement structure of theantenna unit50 will be described.
• FIG.6 is a longitudinal sectional view of theantenna unit50 as viewed from the front side,FIG.7 is a longitudinal sectional view of theantenna unit50 as viewed from the rear side,FIG.8 is a cross-sectional view of theantenna unit50 as viewed from the right side, andFIG.9 is a perspective view when anupper cover body53 of theunit cover51 is separated.
• The unit cover51 of theantenna unit50 is mounted on thetractor1 in a posture such that the left-right width direction of thevehicle body unit2 with respect to the forward direction is in the longitudinal direction. As illustrated inFIGS.6 to9, theunit cover51 includes alower cover body52 which is made of resin, has a substantially rectangular shape in a plan view, and the upper side of which is opened, and theupper cover body53 which is made of resin, has a substantially rectangular shape, and the lower side of which is opened. An opening joint part of theupper cover body53 is externally fitted and detachably joined to an opening joint part of thelower cover body52 in a watertight manner. As illustrated inFIG.9, the opening joint part of theupper cover body53 and the opening joint part of thelower cover body52 are fixedly coupled byscrews54 in one place on each of the left and right side walls and two places in the left and right direction on the rear wall.
• As illustrated inFIGS.6 to9, abase plate55 made of metal, which is an example of a unit base configured to be mounted on thetractor1, is mounted on the upper surface of abottom plate part52A of thelower cover body52. Thebase plate55 is made of a sheet metal having a substantially rectangular shape in a plan view, and is mounted on thelower cover body52 in a posture such that the left-right width direction of thevehicle body unit2 with respect to the forward direction is the longitudinal direction. A gap is formed as a set interval between the lower surface of thebase plate55 and the upper surface of thebottom plate part52A of thelower cover body52. As illustrated inFIGS.5 to7, mountingrecesses52aprotruding inward to a position where thebottom plate part52A can contact the lower surface of thebase plate55 are formed in a plurality of places (four places in the present embodiment) of thebottom plate part52A of thelower cover body52, and the gap is defined to the set interval by the lower surface of thebase plate55 placed on the upper surface of the mounting recesses52a. Each of the mountingrecess52aof thebottom plate part52A of thelower cover body52 and thebase plate55 are fixedly coupled to each other by afirst bolt56 and afirst nut57.
• As illustrated inFIGS.6 and7, to the lower surface of thebase plate55, firstcylindrical screw members90 for mounting thebase plate55 on thesupport frame100 on thetractor1 side are fixed in two places which are positioned apart from each other outward in the longitudinal direction on each of the front and rear sides with respect to a central mounting region of theinertial measurement unit25 and theGNSS antenna26 described later. The lower end of each of thefirst screw members90 penetrates thebottom plate part52A of thelower cover body52 and slightly protrudes downward. Among them, at the lower ends of a pair of front and rearfirst screw members90 located at one end side in the longitudinal direction of thebase plate55 and the lower ends of a pair of front and rearfirst screw members90 located at the other end side in the longitudinal direction, horizontalcoupling plate parts91aof a pair of left andright coupling members91 that are bent and formed in a substantially inverted “L”-shape when viewed from the front of the vehicle body are placed. The horizontalcoupling plate parts91aof both thecoupling members91 are fixedly coupled bysecond bolts92 that penetrate the horizontalcoupling plate parts91aand are screwed into the respectivefirst screw members90 from below. In this fixed coupling state, it is configured such that a gap is formed between the lower surface of thebottom plate part52A of thelower cover body52 and the upper surface of the horizontalcoupling plate part91aof thecoupling members91 so that the load on thebase plate55 side is not applied to thelower cover body52.
• As illustrated inFIGS.6 and7, in two left and right places on the lower surface of thebase plate55 in the front end part at the center in the longitudinal direction (the front end part of thebase plate55 which is on the front side of thevehicle body unit2 when it is mounted on the tractor1), cylindricalsecond screw members93 for mounting a camera78 (seeFIGS.3 and9) for capturing an image of an area in front of the vehicle body are fixed. The lower end of each of thesecond screw members93 penetrates thebottom plate part52A of thelower cover body52 and protrudes slightly downward. A mounting bracket (not illustrated) for the camera78 (seeFIGS.3 and9) placed at the lower ends of thesecond screw members93 is fixedly coupled by bolts (not illustrated) screwed into thesecond screw members93 from below. It is configured such that, in this fixed coupling state, a gap is formed between the lower surface of thebottom plate part52A of thelower cover body52 and the upper surface of the mounting bracket for thecamera78 so that the load on thecamera78 side is not applied to thelower cover body52.
• As illustrated inFIGS.6,7, and9, at the center in the longitudinal direction of thebase plate55, theinertial measurement unit25 and theGNSS antenna26, which are placed at the center position or substantially the center position in the left-right width direction of thevehicle body unit2, are provided in a state where theinertial measurement unit25 and theGNSS antenna26 are overlapped with each other vertically. Among theinertial measurement unit25 and theGNSS antenna26, theGNSS antenna26 is placed at a position above theinertial measurement unit25.
• Specifically, as illustrated inFIGS.6 and7, ahousing25A of theinertial measurement unit25 is fixedly coupled to thebase plate55 bythird bolts58 in a state where the center position in the left-right direction of thehousing25A is located at the center position in the longitudinal direction of thebase plate55.
• On the other hand, as illustrated inFIGS.6 and7, ahousing26A of theGNSS antenna26 is mounted on thebase plate55 via a metal hat-shapedfirst bracket60 in a state where the center position in the left-right direction of thehousing26A is located at the center position in the longitudinal direction of thebase plate55. Thefirst bracket60 is formed in a hat shape detouring above thehousing25A of theinertial measurement unit25 along the longitudinal direction of thebase plate55. Bothleg portions60aof the hat-shapedfirst bracket60 are fixedly coupled to thebase plate55 byfourth bolts61. The width of the hat-shapedfirst bracket60 in the front-rear direction (also the front-rear direction of the vehicle body) is set to be slightly larger than the front-rear width of thehousing25A of theinertial measurement unit25, and as illustrated inFIG.6, afront plate60bcovering the front side of theinertial measurement unit25 is formed in a bent shape at the front edge of thefirst bracket60. With this configuration, thefirst bracket60 is configured as a shielding wall shielding between thefirst bracket60 and thewireless communication unit27 described later.
• Further, as illustrated inFIGS.6 and7, a first predetermined distance L1 between theGNSS antenna26 mounted on thefirst bracket60 and aninner surface53aof theupper cover body53 of theunit cover51 at the center in the longitudinal direction is set to 30 mm or more.
• With the arrangement of theinertial measurement unit25 and theGNSS antenna26 described above, theinertial measurement unit25 and theGNSS antenna26 are placed vertically at the center position or substantially the center position in the left-right width direction of thevehicle body unit2 in a state where theantenna unit50 is mounted on thetractor1 as illustrated inFIGS.3,6, and7. Accordingly, it is possible to improve both the detection accuracy of the current position information of thetractor1 acquired from the reception signal of theGNSS antenna26 and the detection accuracy of the displacement information and the azimuth information of the vehicle body acquired from theinertial measurement unit25. In addition, the width of theunit cover51 in the front-rear direction is reduced, which makes theantenna unit50 more compact.
• Moreover, with the above arrangement, as illustrated inFIGS.6 and7, only theupper cover body53 made of resin is present above theGNSS antenna26, and there is no radio wave shield. Therefore, for example, unlike a case where theinertial measurement unit25 is placed above theGNSS antenna26, theinertial measurement unit25 is not a hindrance for reception at theGNSS antenna26, and carrier phases from a predetermined number of positioning satellites45 (satellite positioning information) can be reliably received.
• Further, as described above, since the first predetermined distance L1 between theGNSS antenna26 and theinner surface53aof theupper cover body53 of theunit cover51 is set to 30 mm or more, radio interference due to the close proximity between theGNSS antenna26 and theinner surface53aof theunit cover51 is suppressed, thereby making it possible to improve the detection accuracy of the current position information of thetractor1 acquired from the reception signal of theGNSS antenna26.
• As illustrated inFIGS.6 to8, at one end in the longitudinal direction of the base plate55 (the right end in the left-right direction of thevehicle body unit2 with respect to the forward direction), ahousing27A of the wireless communication unit (an example of a wireless communication device built in the antenna unit50)27 provided with twowireless communication antennas28 in the left-right direction is fixedly coupled byfifth bolts62. The twowireless communication antennas28 of thewireless communication unit27 are placed in parallel in the front part of thebase plate55 and along the longitudinal direction of thebase plate55. With this arrangement, a sufficient distance from the twowireless communication antennas28 to the front of the cabin frame200 (seeFIG.4), which is a metal component of thetractor1, can be secured.
• Further, the twowireless communication antennas28 of thewireless communication unit27 make it possible to increase the speed of communication with thewireless communication device31 of thewireless communication terminal30. In addition, since the twowireless communication antennas28 are placed in parallel in the front part of thebase plate55 and along the longitudinal direction of thebase plate55, it is less likely for both thewireless communication antennas28 to be affected by radio wave shielding by thecabin frame200 being a metal component of thetractor1, so that a satisfactory communication of thewireless communication unit27 can be maintained.
• Further, the outer periphery of theinertial measurement unit25 is shielded by themetal housing25A at many portions except for a connector and the like, and the metal hat-shapedfirst bracket60 located between thewireless communication unit27 and theinertial measurement unit25, functions as a shielding wall. Accordingly, radio interference between thewireless communication unit27 and theinertial measurement unit25 can be suppressed.
• As illustrated inFIGS.6,7, and9, at the other end in the longitudinal direction of the base plate55 (the left end in the left-right direction of thevehicle body unit2 with respect to the forward direction), the base station antenna (an example of a wireless communication device built in the antenna unit50)29 configured to receive information from thereference station40 is placed. As a result, thewireless communication unit27, the GNSS antenna26 (the inertial measurement unit25), and thebase station antenna29 are placed on thebase plate55 in this order from the right in the left-right direction of thevehicle body unit2 with respect to the forward direction to be arranged in a line in the left-right direction of thevehicle body unit2. As illustrated inFIGS.6,7, and9, thebase station antenna29 includes abase29A including amagnet65 and a round bar-shapedantenna bar29B extending upward from thebase29A.
• Further, as illustrated inFIGS.6,7 and9, a raisingpart95 configured to place thebase station antenna29 in a higher place than the antenna mounting part is provided between thebase station antenna29 and the antenna mounting part of thebase plate55. As illustrated inFIGS.6 and7, the raisingpart95 includes a raisingbracket96 formed by bending a metal plate twice at right angles. The raisingbracket96 includes a mountingboard part96ain a horizontal posture fixedly coupled to the other end of thebase plate55 in the longitudinal direction bysixth bolts97 andsixth nuts98, a raisingplate part96bextending in a vertical posture upward from one end of the mountingboard part96a, and an antenna mountingplate part96chorizontally extending from the upper end of the raisingplate part96b.
• In the above arrangement of thebase station antenna29, a separation distance between theantenna bar29B of thebase station antenna29 located at the other end in the longitudinal direction and thewireless communication antenna28 of thewireless communication unit27 located at one end in the longitudinal direction is large. Accordingly, it is possible to suppress radio interference between theantenna bar29B of thebase station antenna29 and thewireless communication antenna28 of thewireless communication unit27.
• In addition, it is possible to easily mount thebase station antenna29 on the raisingbracket96 made of metal by the magnetic force of themagnet65 provided in thebase29A. Moreover, the upper end part of thebase station antenna29 can be placed in a higher place by the height of the raisingbracket96, and thus, it is possible to improve the reception performance with respect to the reference stationwireless communication device41 of thereference station40 while preventing thebase station antenna29 from breaking due to swinging caused by traveling vibration and the like of thetractor1, as compared with a case where a longbase station antenna29 is used.
• Next, theunit cover51 of theantenna unit50 will be described. As illustrated inFIGS.6 to9, in a front half on one end side in the longitudinal direction (the right end side in the left-right direction of thevehicle body unit2 with respect to the forward direction) of theupper cover body53 of theunit cover51, abulge part53A protruding upward from the upper surface position at the center in the longitudinal direction of theupper cover body53 and the upper end positions of bothwireless communication antennas28 of thewireless communication unit27 is formed. Further, as illustrated inFIGS.6 and8, a second predetermined distance L2 between aninner surface53bof thebulge part53A and the upper ends of thewireless communication antennas28 is set to 30 mm or more.
• The second predetermined distance L2 formed between the upper end of thewireless communication antenna28 and theinner surface53bof thebulge part53A of theupper cover body53 makes it possible to suppress radio interference due to the close proximity between thewireless communication antenna28 and theinner surface53bof theunit cover51. Accordingly, it is possible to improve the communication accuracy between thewireless communication unit27 and thewireless communication device31 of thewireless communication terminal30.
• Further, as illustrated inFIG.9, a throughhole70 through which theantenna bar29B of thebase station antenna29 penetrates and which protrudes outward and upward is formed in the other end part of theupper cover body53 in the longitudinal direction. As illustrated inFIGS.6,7, and9, a vibration-proofelastic body71 such as a tube lubber contacting an outer peripheral surface of a penetration part of theantenna bar29B of thebase station antenna29 is attached to the periphery of the opening of the throughhole70. A grommet which contacts the entire circumference of theantenna bar29B and also exhibits water tightness is employed for the vibration-proofelastic body71.
• If the vibration-proofelastic body71 is not provided, an annular gap is present between the periphery of the opening of the throughhole70 of theupper cover body53 and the outer peripheral surface of the penetration part of theantenna bar29B. If traveling vibration of thetractor1 or the like acts on thebase station antenna29, theantenna bar29B swings in the range of the annular gap, which may result in breakage of theantenna bar29B at its root. However, in the present embodiment, as described above, since a vertical middle part of theantenna bar29B is supported by the vibration-proofelastic body71 provided in the periphery of the opening of the throughhole70 of theupper cover body53 so that the support structure of thebase station antenna29 is a two-point support structure as a whole, it is possible to prevent theantenna bar29B from breaking due to traveling vibration or the like.
• It is noted that, in the embodiment, the vibration-proofelastic body71 is attached to the periphery of the opening of the throughhole70 of theupper cover body53, but the vibration-proofelastic body71 may be attached to the upper surface or theinner surface53aof theupper cover body53.
• As illustrated inFIGS.6,10, and11, a mountingspace73 is formed for anotherunit72 between both theinertial measurement unit25 and theGNSS antenna26 and thebase station antenna29 on the other end side in the longitudinal direction of thebase plate55. Here,FIGS.6,7, and9 illustrate a state in which theother unit72 is not mounted in the mountingspace73 and the mountingspace73 is a hollow space.FIGS.10 and11 illustrate a state in which theother unit72 is mounted in the mountingspace73.
• Theother unit72 may be, for example, a controller for a retrofit liquid crystal monitor configured to control a part of the automatic traveling control, or the like. In thetractor1 following the automatic traveling specification according to the present embodiment, a liquid crystal monitor47 is provided in thecabin7, and the liquid crystal monitor47 is equipped with a controller configured to control a part of the automatic traveling control. However, if another work vehicle such as a rice transplanter following a normal specification is changed to follow the automatic traveling specification, a controller configured to control the automatic traveling for a retrofit liquid crystal monitor is required. In this case, the controller can be easily mounted by using the mountingspace73 secured in thebase plate55.
• Further, as illustrated inFIGS.6 and7, the camera78 (seeFIGS.3 and9) for capturing an image of an area in front of the vehicle body is placed at the lower ends of the bothsecond screw members93 protruding from thebottom plate part52A of thelower cover body52. A mounting bracket (not illustrated) for thecamera78 is fixedly coupled to thesecond screw members93 by bolts (not illustrated) screwed from below. It is configured such that the image captured by thecamera78 can be displayed on the touch panel of thewireless communication terminal30 via wireless communication between thewireless communication unit27 of thetractor1 and thewireless communication device31 of thewireless communication terminal30.
• It is noted that, inFIGS.6 to11, wires connected to theinertial measurement unit25, theGNSS antenna26, thewireless communication unit27, and thebase station antenna29 which are built on thebase plate55 are omitted.FIGS.3 and4 illustrate a part of oneharness80 in which the wires are assembled in theunit cover51. As illustrated inFIG.4, theharness80 is led out from a harness lead-out hole81 (seeFIG.9) formed at the center in the longitudinal direction of the rear wall of thelower cover body52. A grommet (not illustrated) is mounted on the harness lead-out hole81.
• Next, a mounting structure of theantenna unit50 will be described. As illustrated inFIGS.1 and3 to5, both ends of thesupport frame100 of theantenna unit50 are fixedly coupled to mirror mountingparts150 provided on left and right front supports201 constituting thecabin frame200.
• As illustrated inFIGS.3 to5, in each of the left and rightmirror mounting parts150, a mountingbase151 formed in a substantially “U” shape in a plan view is fixed to the upper part of each of the front supports201 by welding or the like, and amirror mounting member152 having a hinge for rotatably supporting asupport arm111 of arearview mirror110 is fixedly coupled to the mountingbase151 by a bolt (not illustrated).
• Asecond bracket112 extending upward (specifically, directly above) when viewed from the side of the vehicle body is fixedly fastened by a bolt between each of the left and right mountingbases151 and each of the left and rightmirror mounting members152. Thesecond bracket112 includes a verticalsupport plate part112aextending upward from between the mountingbase151 and themirror mounting member152, a mountingplate part112bbent along a horizontal plane from the upper end of the verticalsupport plate part112a, and a reinforcingplate part112cfixed to a bent corner formed by the verticalsupport plate part112aand the mountingplate part112b.
• As illustrated inFIGS.3 to5, thesupport frame100 includes a pipe-shapedsupport member101 having a circular cross section formed by bending both ends in the left-right width direction downward in a substantially flat gate shape when viewed from the front of the vehicle body. Mountingplates102 having a substantially “L”-shape when viewed from the front of the vehicle body and having a mounting lower surface along a horizontal plane are fixed to both ends of the pipe-shapedsupport member101. Reinforcingplates103 are fixed to both end parts of the pipe-shapedsupport member101 and both the mountingplates102.
• Both the mountingplates102 of thesupport frame100 are placed on the upper surfaces of the mountingplate parts112bof the left and rightsecond brackets112 which are each fixedly fastened between the mountingbase151 and themirror mounting member152. Both the placed mountingplates102 of thesupport frame100 and the mountingplate parts112bof both thesecond brackets112 are fixedly coupled to each other byseventh bolts104 andseventh nuts105, respectively.
• As described above, the left and rightmirror mounting parts150 are mounted on the upper part of the front supports201 of therigid cabin frame200, and are placed at a height close to aroof190 of thecabin7. Accordingly, with no more than adding a simple support structure in which both themirror mounting parts150 which are sturdy and have a high ground height are used and thesecond brackets112 extend upward (specifically, directly above) from both themirror mounting parts150, it is possible to firmly mount thesupport frame100 of theantenna unit50 at an appropriate height.
• In addition, the upper mounting surface of the mountingplate part112bof each of the left and rightsecond brackets112, which is fixedly fastened between the mountingbase151 and themirror mounting member152, and the lower mounting surface of each of the mountingplates102 of thesupport frame100 are both formed on a horizontal plane. Accordingly, this makes it easy to place a middle part of the pipe-shapedsupport member101 horizontally along the left-right direction, which makes it possible to reduce an error in mounting of theantenna unit50 mounted on the horizontal middle part of the pipe-shapedsupport member101.
• Further, as illustrated inFIGS.3 to5, in a state where thesupport frame100 is laid between the left and rightsecond brackets112, the horizontal middle part of the pipe-shapedsupport member101 of thesupport frame100 is horizontally placed along the left-right width direction of the vehicle body at a position above and near the front end of theroof190 of thecabin frame200.
• As illustrated inFIGS.3 to5, a pair of left and rightthird brackets120, each having a substantially “L”-shape when viewed from the side of the vehicle body, which support the pair of right and leftcoupling members91 of theantenna unit50 are fixed to the horizontal middle part of the pipe-shapedsupport member101. Verticalcoupling plate parts91bof both thecoupling members91 facing close to each other in the left-right width direction of thevehicle body unit2 on theantenna unit50 side, and both thethird brackets120 on thesupport frame100 side are fixedly coupled by twoeighth bolts121 horizontally along the left-right width direction of thevehicle body unit2 and eighth nuts122.
• In a state where the verticalcoupling plate parts91bof both thecoupling members91 on theantenna unit50 side are fixedly coupled to both thethird brackets120 on thesupport frame100 side by two sets of the twoeighth bolts121 andeighth nuts122, theantenna unit50 is in a working position (work posture) in which thebase station antenna29 mounted on theantenna unit50 is oriented vertically.
• Circular first bolt insertion holes126 (seeFIG.16) are formed in two front and rear places of each of the verticalcoupling plate parts91bof each of both thecoupling members91. In each of both thethird brackets120 on thesupport frame100 side, a second oblongbolt insertion hole123 horizontally along the front-rear direction is formed, and the second oblongbolt insertion hole123 has a length corresponding to the pitch of the first bolt insertion holes126. In each of both thethird brackets120 on thesupport frame100 side, a circular secondbolt insertion hole124 is formed in a part which is located immediately below the front end position of the second oblongbolt insertion hole123 and at a vertically spaced position corresponding to the pitch of both the first bolt insertion holes126.
• Then, as illustrated inFIG.4, in a state where theantenna unit50 is in the working position, theeighth bolt121 on the front side is removed, and theeighth bolt121 on the rear side is loosened. In this state, theeighth bolt121 on the rear side is moved forward along the second oblongbolt insertion hole123 of each of both thethird brackets120 to the front end position together with theantenna unit50, and theantenna unit50 is turned downward around the axis of theeighth bolt121. In a state in which theantenna unit50 is turned to the lower front side, theantenna unit50 hangs down around theeighth bolt121 as a pivot, so that the first bolt insertion holes126 on the front end side of both thecoupling members91 on theantenna unit50 side are aligned with the second bolt insertion holes124 of both thethird brackets120 on thesupport frame100 side (seeFIG.16). The removedeighth bolts121 are inserted into the aligned first bolt insertion holes126 and second bolt insertion holes124, and each of theeighth bolts121 is screwed to the tightening side so that both thecoupling members91 on theantenna unit50 side are fixedly coupled to both thethird brackets120 on thesupport frame100 side. In this fixed coupling state, as illustrated inFIG.12, theantenna unit50 is in a non-working position (non-working posture) where thebase station antenna29 mounted on theantenna unit50 is directed horizontally in the front side to make its front side lower.
• With the configuration described above, theantenna unit50 is mounted on thesupport frame100 to be displaceable from the working position to the non-working position on the lower front side. Further, the second oblong bolt insertion holes123 of both thethird brackets120, the first bolt insertion holes126 on the rear end side of both thecoupling members91 on theantenna unit50 side, and theeighth bolts121 constitute aguide unit125 configured to guide theantenna unit50 to be moved in the front-rear direction between the working position and the non-working position on the lower front side.
• In the present embodiment, as illustrated inFIGS.12 and13, the non-working position of theantenna unit50 is a position where theantenna unit50 is moved to the front side from the working position to the maximum within the movable range of the bolt in the second oblongbolt insertion hole123, and where theantenna unit50 is turned downward by 90 degrees around theeighth bolt121 contacting the front end position of the second oblongbolt insertion hole123. In this non-working position, thebase station antenna29 is in a posture of protruding forward in the horizontal direction as described above.
• Then, as illustrated inFIGS.1,4, and13A, in a state where theantenna unit50 is in the working position, thebase station antenna29 and a part of theunit cover51 of theantenna unit50 protrude upward from a highest horizontal line X passing through ahighest part190aof theroof190 of thecabin7. However, when thebase station antenna29 protruding upward from theroof190 of thecabin7 is obstructed during transportation of thetractor1 or the like, theantenna unit50 is changed from the working position to the non-working position on the lower front side as illustrated inFIGS.12 and13B. In this non-working position, thebase station antenna29 is in a posture of protruding forward in the horizontal direction, which makes it possible to place theantenna unit50 including theunit cover51 at a position substantially equal to or lower than thehighest part190aof the top surface of theroof190 of thecabin7. In the present embodiment, as illustrated inFIGS.12 and13B, when theantenna unit50 is in the non-working position, the upper side surface of the opening joint part of theupper cover body53 is ahighest part50aof theantenna unit50. Thehighest part50aof theantenna unit50 in the non-working position is set at the same height position as the highest horizontal line X passing through thehighest part190aof theroof190 of thecabin7.
• Further, in the present embodiment, the operation of changing the position of theantenna unit50 between the working position and the non-working position is performed manually, but the operation of changing the position of theantenna unit50 may be performed by a drive unit such as an actuator.
• Whether theantenna unit50 is in the working position can be detected based on displacement information acquired from theinertial measurement unit25. Accordingly, as illustrated inFIG.2, thecontrol unit23 includes an automatictraveling restraint unit46 configured to prohibit the start of the automatic traveling control based on information acquired by theinertial measurement unit25 and theGNSS antenna26 during no detection of theantenna unit50 in the working position.
• The above-described automatictraveling restraint unit46 allows the automatic traveling control to be started only when theantenna unit50 is in the working position. Accordingly, it is possible to allow the vehicle body to automatically and safely travel along the target traveling route with high accuracy based on accurate information acquired by theinertial measurement unit25 and theGNSS antenna26.
• It is noted that, in the present embodiment, whether theantenna unit50 is in the working position is detected based on the displacement information acquired from theinertial measurement unit25, but whether theantenna unit50 is in the working position may be determined based on a signal of an automatic switch for detecting a position displacement of theantenna unit50 or a signal of a hard switch manually operated.
• Next, a wiring structure of theharness80 led out from theantenna unit50 will be described.
• As illustrated inFIGS.14 and15, thecabin frame200 in which theharness80 is wired is formed in a substantially box frame shape that includes a pair of left and right front supports201 located in front of the driver's seat9 (seeFIG.1), a pair of left and right rear supports202 located behind the driver's seat9, afront beam member203 coupling the upper ends of the front supports201, arear beam member204 coupling the upper ends of the rear supports202, and left and rightside beam members205 each coupling the upper ends of the front supports201 and the rear supports202 which are arranged in front and rear.
• As illustrated inFIGS.14 and15, the lower end of each of the rear supports202 is coupled to an upper rear end part of afender frame207 curved to bulge rearward and upward in a side view to conform to the shape of arear fender206, and a lower front end part of thefender frame207 is coupled to the rear end of aside frame208 protruding rearward from a lower part of the corresponding one of the front supports201.
• As illustrated inFIG.14, thefender frame207 is formed of a cylindrical frame material. Among them, the lower front part of thefender frame207 located on the right side of thecabin7 opens downward and outward of thecabin7, and an internal space of thefender frame207 located on the right side is formed in an inside andoutside communication passage210 communicating the inside and outside of thecabin7. A drain hose (not illustrated) for discharging dew water in an air conditioner to the outside of thecabin7 is provided in the inside andoutside communication passage210 of thefender frame207.
• Further, awindshield212 is placed in a region surrounded by the left and right front supports201, thefront beam members203, and lowerfront plate boards211 extending inward from the lower ends of the front supports201 in the left and right direction.
• Then, as illustrated inFIGS.14 and15, theharness80 led out from theantenna unit50 extends in a right edge (an example of one edge in the left-right width direction) on the outer surface of thewindshield212 of thecabin7 and downward along a band-shaped part overlapping aglass receiving part201aof thefront support201 on the right side. Theharness80 reaching one of the lowerfront plate boards211 on the lower end side of thewindshield212 extends rearward along the lower surface of a floorplate support plate213 continuously connected to theside frame208, is then guided into thecabin7 from the opening at the lower front end of thefender frame207 located on the right side at the lower front end through the inside andoutside communication passage210, and is connected to thecontrol unit23 placed in anoperation panel unit214 on the right side.
• The band-shaped part overlapping theglass receiving part201aof thefront support201 on the right side and being at a right side edge on the outer surface of thewindshield212 is a glass attaching part for attaching thewindshield212 to the front part of thecabin7, and is also in a position that does not interfere with viewing. Therefore, when theharness80 led out from theantenna unit50 is placed in the above-described band-shaped part, it is possible to place theharness80 in a good appearance while maintaining the visibility of an operator seated on the driver's seat9 in a good condition.
• Further, as illustrated inFIG.15, aprotective harness cover250 made of resin through which theharness80 is inserted is adhered to the band-shaped part at the right side edge of thewindshield212 on the outer surface of thewindshield212 with an adhesive or the like.
Another Embodiment
• In the above-described embodiment, the second oblong bolt insertion holes123 of both thethird brackets120 of thesupport frame100 are formed in a straight line along the front-rear direction. However, as illustrated inFIG.16, recesses123a, each receiving theeighth bolts121 inserted through the firstbolt insertion hole126 and the secondbolt insertion hole124 on the lower side, may be formed at both ends in the front-rear direction of each of the second oblong bolt insertion holes123.
• Then, when theantenna unit50 is changed from the working position to the non-working position on the lower front side, theeighth bolt121 on the front side is first removed, and theeighth bolt121 on the rear side is loosened. In this state, theeighth bolts121 located in therecesses123aon the rear end side of the second oblong bolt insertion holes123 are pulled up and moved forward together with theantenna unit50. The movedeighth bolts121 are dropped into therecesses123aon the front end side of the second oblong bolt insertion holes123, and theantenna unit50 is turned downward around the axis of theeighth bolts121. At this time, since theeighth bolts121 are securely held in therecesses123aon the front end side of the second oblong bolt insertion holes123, theantenna unit50 is easily turned around the axis of theeighth bolts121.
• In a state in which theantenna unit50 is turned to the lower front side, theantenna unit50 hangs down around theeighth bolts121 as a pivot, so that the first bolt insertion holes126 on the front end side of both thecoupling members91 on theantenna unit50 side are aligned with the second bolt insertion holes124 of both thethird brackets120 on thesupport frame100 side. The removedeighth bolts121 are inserted into the aligned first bolt insertion holes126 and second bolt insertion holes124, and each of theeighth bolts121 is screwed to the tightening side so that both thecoupling members91 on theantenna unit50 side are fixedly coupled to both thethird brackets120 on thesupport frame100 side. In this fixed coupling state, theantenna unit50 is in a non-working position (non-working posture) where thebase station antenna29 mounted on theantenna unit50 is directed horizontally in the front side to make its front side lower.
Other Embodiments
• (1) In the above-described embodiments, thewireless communication antenna28 of thewireless communication unit27 is housed inside theunit cover51 of theantenna unit50. However, as required, thewireless communication antenna28 may protrude outward and upward from a through hole formed in theupper cover body53.
• (2) In the above-described embodiments, the first predetermined distance L1 between theGNSS antenna26 and theinner surface53aof theupper cover body53 of theunit cover51 is set to 30 mm or more. However, the first predetermined distance L1 can be set to any value according to the reception state of carrier phases (satellite positioning information) from a predetermined number ofpositioning satellites45.
• (3) In the above-described embodiments, the second predetermined distance L2 between theinner surface53bof thebulge part53A of theunit cover51 and the upper ends of thewireless communication antennas28 is set to 30 mm or more. However, the second predetermined distance L2 can be set to any value according to the communication state between thewireless communication unit27 and thewireless communication device31 of thewireless communication terminal30.
• (4) In the above-described embodiments, the pair of left andright coupling members91 are mounted on the lower surface side of theunit cover51. However, the mounting structure is not limited to this, and any mounting structure can be adopted according to the mounting condition on both sides of the work vehicle.
• (5) In the above-described embodiments, the twowireless communication antennas28 of thewireless communication unit27 are placed in parallel. However, a singlewireless communication antenna28 may be used, or three or morewireless communication antennas28 may be used to be placed in parallel.
• (6) In the above-described embodiments, the raisingpart95 is composed of the raisingbracket96 formed by bending a metal plate twice at right angles, but it is not limited to this structure. The raisingpart95 may have any structure as long as thebase station antenna29 can be placed in a higher place than the antenna mounting part.
INDUSTRIAL APPLICABILITY
• The present invention is preferably applicable to a work vehicle with a cabin, and in particular, a work vehicle suitable in automatic traveling (including self-driving) of the work vehicle such as a tractor along a target traveling route while acquiring position information of the work vehicle by using a Global Navigation Satellite System (GNSS), and applicable also to an antenna unit for a work vehicle.
DESCRIPTION OF REFERENCE NUMERALS
• • 1 Work vehicle (tractor)
  • 7 Cabin
  • 25 Inertial measurement unit
  • 26 GNSS antenna
  • 27 Wireless communication device (wireless communication unit)
  • 29 Wireless communication device (base station antenna)
  • 40 Reference station
  • 46 Automatic traveling restraint unit
  • 50 Antenna unit
  • 51 Unit cover
  • 55 Unit base (base plate)
  • 72 Another unit
  • 73 Mounting space
  • 95 Raising part
  • 100 Support frame
  • 112 Bracket (second bracket)
  • 125 Guide unit
  • 190aHighest part
  • 200 Cabin frame
  • L1 Distance (first predetermined distance)

Claims (5)

1-8. (canceled)

9: A work vehicle comprising:

a tractor with a cabin;

a support frame arranged along a left-right width direction at an upper position outside the cabin; and

a GNSS antenna supported by the support frame while positioned in the center of a left-right width direction of a body of the tractor.

10: The work vehicle according toclaim 9, further comprising:

a camera positioned below the GNSS antenna.

11: The work vehicle according toclaim 10,

wherein the camera is directly or indirectly supported by the support frame.

12: The work vehicle according toclaim 10,

wherein a gap is provided between a bottom surface of an antenna unit containing the GNSS antenna and a top surface of a mounting bracket of the camera.

Images