CN111001829A - Lathe rotation error detection monitoring device - Google Patents

Abstract

The invention relates to a lathe rotation error detection monitoring device which comprises a main controller, a transmitter, a reflector and a flat mirror, wherein the transmitter can be installed on a lathe and coaxially rotates with a lathe spindle, the transmitter is provided with a front surface and a back surface which are parallel, the back surface faces the lathe spindle, the front surface is provided with a light sensor, the center of the sensor is provided with a fine hole, a laser light source is arranged in the hole and outwards emits laser light at an angle vertical to the front surface, the transmitter is communicated with the main controller and can transmit incident light received by the light sensor to the main controller, the reflector comprises a semi-transparent and semi-reflective mirror, the mirror surface of which forms an included angle α with the laser light, the receiver is communicated with the main controller, the flat mirror is arranged on a transmission light path of the laser light transmitting through the semi-transparent and semi-reflective mirror, when detection is carried out, the laser light is found by the laser light source on the transmitter, part of the light transmits the semi-transparent and semi.

Description

Lathe rotation error detection monitoring device

Technical Field

The application relates to a lathe auxiliary device, concretely relates to lathe gyration error detection monitoring device.

Background

A lathe is a machine tool most commonly used in machining, and a workpiece is clamped by a spindle box (also called a head box) through a chuck, so that the workpiece is fixed on a spindle to rotate (called a main motion) together with the spindle, and a tool is driven by a feed to move (called a feed motion) toward the workpiece to be in contact with the workpiece to cut.

The lathe is generally used for processing a cylindrical revolving body, and the processing precision is mainly influenced by a guide rail error and a main shaft revolving error. Fig. 1 shows the error of the spindle in a simplified manner. The spindle rotation error is again divided into pure axial bouncing (a), pure radial bouncing (b) and pure angular swinging (c), in fig. 1 the solid line represents the ideal position of the lathe spindle, and the dashed line represents the actual position of the spindle when the corresponding error occurs. In the process of using the lathe, three rotation errors of the spindle need to be detected and calibrated respectively, and the separation detection is difficult because the pure radial run-out and the pure angle swing are close to each other in appearance.

Meanwhile, the no-load error of a static lathe is easy to measure, but after the lathe starts to perform cutting movement, the main shaft and a cutter have violent interaction through a workpiece, so that a very large internal force is generated, the error of the lathe during working is completely different from that during no-load, and a technical means for detecting the rotation error on line during cutting of the lathe is lacked at present. And it is not easy to judge when the tool enters into cutting.

CN108296500A discloses a device and a method for rapidly detecting the machining precision of a modular numerical control lathe, and particularly discloses a detection device which comprises a framework module, a line laser detection module and a fiber probe detection module; the line laser detection module comprises a line laser emitting end, a line laser receiving end and an inner gear ring; the optical fiber probe detection module comprises a circuit board shell, a roughness optical fiber probe, a ranging laser probe and a metal contact pin; the circuit board shell, the roughness optical fiber probe and the fixed support are integrated; the distance measuring laser probe and the metal contact pin are integrated; the detection method of the detection device comprises the following steps: the mounting line laser detection module detects the roundness and radial runout of the workpiece; installing an optical fiber probe detection module to detect the surface roughness, axial runout and end face turning precision of the workpiece; the invention can detect the shape error, the rotation error, the surface roughness and the turning end face precision of the processed workpiece on line in real time on the premise of not changing the clamping relation of the workpiece. This scheme adopts the laser gauge head to carry out the on-line monitoring of turning error, but sets up itself and needs certain timing, is limited to the installation size, uses also to have certain injecing, and the structure is comparatively complicated simultaneously.

Disclosure of Invention

Based on the current situation of above-mentioned prior art, provide this application, this application relates to a lathe gyration error detection monitoring device.

Technical problem to be solved

(1) Separating pure axial errors and pure angle swing which play a main role in machining from main shaft errors of the lathe, and respectively detecting and monitoring;

(2) the no-load (idle in the time of adjustment) and the cutting working condition of the lathe are distinguished and detected respectively.

(II) technical scheme

The technical scheme of the invention is as follows:

a lathe rotation error detection monitoring device is installed on a lathe and used together with the lathe, and is characterized by comprising:

a main controller;

the emitter can be arranged on the lathe and coaxially rotates with the lathe spindle, the emitter is provided with a front surface and a back surface which are parallel, the back surface faces the lathe spindle, the front surface is provided with a light sensor, the center of the light sensor is provided with a fine hole, a laser light source is arranged in the hole, and laser light rays are emitted outwards at an angle vertical to the front surface; the emitter is communicated with the main controller and can transmit incident light received by the light sensor to the main controller;

the reflector comprises a semi-transparent semi-reflecting mirror with a mirror surface forming an included angle α with the laser ray, and the semi-transparent semi-reflecting mirror is positioned on the laser ray light path;

the receiver is provided with a light sensor positioned on a reflection light path of the semi-transparent semi-reflector and is communicated with the main controller;

the plane mirror is arranged on a transmission light path of the laser light penetrating through the semi-transparent semi-reflecting mirror, and the mirror surface is vertical to the laser light;

when the detection is carried out, a laser light source on the emitter finds laser light, part of the light penetrates through the semi-reflecting and semi-transmitting mirror to shine on the plane mirror, the light is reflected back to the light sensor on the emitter to be received, and the other part of the light is reflected by the semi-reflecting and semi-transmitting mirror to be received by the light sensor projected on the receiver.

Furthermore, the included angle between the semi-transparent and semi-reflective mirror surface of the reflector and the emitted laser light is 45 degrees.

Furthermore, the back of the emitter is provided with a magnet which can be adsorbed on the spindle mechanism or the clamped workpiece end, and the light source of the emitter is substantially on the axis of the spindle.

Further, the transmitter is provided with a battery and communicates with the controller in a wireless mode.

Furthermore, the controller is connected to an electric cabinet of the lathe, can monitor and read voltage and current information of the lathe during operation, and judges whether the lathe is in an unloaded state or a cutting state according to the change of the actual power of the lathe.

Further, the light sensor on the emitter is an area array CCD.

Further, the optical sensor on the receiver is a linear array CCD, and the linear array CCD and the turning tool are located at the same horizontal height.

Further, wherein the pure angular wobble error θ = arctg (lh/(L + L), the pure radial run-out E = E ± htg θ,

in the formula: l is the distance from the emitter to the half-mirror;

l is the distance from the emitter to the plane mirror;

h is the distance from the half-transmitting and half-reflecting mirror to the receiver;

and E is the deviation value from the initial position measured by the linear array CCD.

Furthermore, the receiver and the semi-transparent and semi-reflective mirror are arranged on the center frame, and the plane mirror is arranged on the tailstock.

(III) advantageous effects

(1) The scheme separates two lathe errors which are generally mixed by a simpler means, and is beneficial to improving the precision of the lathe;

(2) judging whether cutting is started or not according to the running state of the lathe, and monitoring the influence of cutting parameters on error values on line or in real time;

(3) and the transmitter is in wireless communication with the controller, so that the installation and the arrangement of the device are greatly simplified, and the cutting machining is not influenced.

Drawings

The attached drawings are simplified schematic diagrams of the device, and the meanings of the diagrams in the figures are shown in the attached description:

FIG. 1 is a schematic diagram of the formation of three common errors of a lathe spindle;

FIG. 2 is a schematic diagram of the arrangement of elements of the present invention

FIG. 3 is a schematic diagram of a pure angular wobble error calculation with the transflective mirror omitted

FIG. 4 is a schematic diagram of a pure radial run out error calculation with flat mirrors omitted

FIG. 5 is a schematic plan view of the present invention in a lathe

Wherein,

1. emitter

2. Light sensor

3. Laser light source

4. Semi-transparent semi-reflecting mirror

5. Receiver with a plurality of receivers

6. Plane mirror

7. Spindle mechanism or cylindrical rotary workpiece

8. Knife rest

9. Centre frame

10. And (4) a tail seat.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

Referring to fig. 2, the following technical solutions are adopted in the present application:

a lathe rotation error detection monitoring device is installed on a lathe and used together with the lathe, and is characterized by comprising:

a main controller;

the laser light source device comprises anemitter 1, alaser light source 3 and a laser light source, wherein theemitter 1 can be arranged on a lathe and coaxially rotates with a lathe spindle, and is provided with a front surface and a back surface which are parallel, the back surface faces to the lathe spindle, the front surface is provided with alight sensor 2, the center of the sensor is provided with a fine hole, and the hole is internally provided with thelaser light source 3 for emitting laser light outwards at an angle vertical to the front surface; theemitter 1 is communicated with a main controller and can transmit incident light received by thelight sensor 2 to the main controller;

the reflector comprises a semi-transparentsemi-reflecting mirror 4 with a mirror surface forming an included angle α with the laser ray, and the semi-transparentsemi-reflecting mirror 4 is positioned on the laser ray light path;

thereceiver 5 is provided with alight sensor 2 positioned on a reflection light path of the half-transmitting and half-reflectingmirror 4, and thereceiver 5 is communicated with the main controller;

a plane mirror 6 which is arranged on a transmission light path of the laser light transmitting through thehalf mirror 4 and has a mirror surface perpendicular to the laser light;

during detection, alaser light source 3 on theemitter 1 finds laser light, part of the laser light penetrates through the semi-reflective and semi-transparent mirror and irradiates on the plane mirror 6, the laser light is reflected back to thelight sensor 2 on theemitter 1 to be received, and part of the laser light is reflected by the semi-reflective and semi-transparent mirror and projects on thelight sensor 2 on thereceiver 5 to be received.

Furthermore, the included angle between the mirror surface of the half-transmitting and half-reflectingmirror 4 on the reflector and the emitted laser light is 45 degrees.

In the error of the lathe spindle, pure radial run-out and pure angular swing are often mixed together and both become the change of the spindle rotation axis, and the reasons for the error of the pure radial run-out and the error of the pure angular swing are different, and if the pure radial run-out and the pure angular swing cannot be detected respectively, the error reduction action cannot be performed correspondingly.

In the above-described embodiment, collimated light emitted from thelaser light source 3 interlocked with the main axis passes through thehalf mirror 4, and a part of the collimated light is transmitted to the plane mirror 6, and is reflected back to thephoto sensor 2 on the outer periphery of the light source, and a part of the collimated light is reflected to thephoto sensor 2 on thereceiver 5. The distance of the light spot on thelight sensor 2 at the periphery of the light source to offset the light source is determined by pure angle swing alone, the distance of the light spot on thelight sensor 2 on thereceiver 5 to offset the ideal position is determined by pure angle swing and radial run-out simultaneously, and the radial run-out can be further derived on the basis that the pure angle swing can be calculated by a geometric light path, so that two errors are separated by light design in the scheme, and the size of the errors can be calculated respectively. When the included angle between the half-transmitting and half-reflectingmirror 4 and the laser ray is 45 degrees, the optical geometric calculation is simplified, but other convenient angles can achieve the same effect.

Further, the back of theemitter 1 is provided with a magnet which can be attached to a spindle mechanism or a clamped workpiece end, and the light source of theemitter 1 is substantially on the axis of the spindle.

Referring to fig. 3-4, the solid line shows the ideal position, and the dotted line shows the actual position of the spindle with error, noting that the spindle position has an angular wobble error and a radial run-out error. According to the optical path analysis, the light source of theemitter 1 does not need to be coaxial with the spindle axis to realize the above detection principle, and the centering of the light source center and the spindle axis is not easy to realize in practical use. The back of theemitter 1 is provided with a magnet, so that the installation mode is simplified to the maximum extent, and the finder only needs to be adsorbed at the position close to the center of the end face of the workpiece.

Further, thetransmitter 1 is provided with a battery and communicates with the controller in a wireless manner.

The devices on thetransmitter 1 are all low power digital devices, and the batteries are easily provided to reduce the wiring arrangement, which further simplifies installation, while communicating with the controller using bluetooth, WLAN, Zigbee or other wireless communication protocols commonly used in portable electronic settings.

Furthermore, the controller is connected to an electric cabinet of the lathe, can monitor and read voltage and current information of the lathe during operation, and judges whether the lathe is in an unloaded state or a cutting state according to the change of the actual power of the lathe.

The controller can also have a log function and record various return parameters from the start-up. In the lathe detection in the prior art, the no-load and cutting state are difficult to judge, generally, the no-load and cutting state are set manually, after the lathe enters cutting, the resistance of the main shaft is increased rapidly, and the actual power of the main shaft is increased, so that after the voltage, the current and the estimated power information of the lathe are recorded through a log function, whether the lathe enters cutting can be judged, and further, if the pure radial run-out or the pure angle swing of the main shaft is increased after the lathe enters cutting is found through analyzing the log, the error of the lathe caused by the cutting parameters (the rotating speed or the feeding amount) is explained.

Because workpieces with different clamping sizes also have influence on the power of the lathe, the controller does not set any threshold value to judge whether the workpieces enter the cutting process, and only records the threshold value as a standard for auxiliary judgment.

The data recorded in the controller can be stored in the controller for later analysis, and can also be transmitted into equipment such as a PC (personal computer) for real-time monitoring and analysis through the upper computer. For a common lathe, a controller needs to be connected to a control box of the lathe, and for a numerical control lathe, required information can be directly read from a numerical control system.

Further, thelight sensor 2 on theemitter 1 is an area array CCD.

The light emitted from thelaser light source 3 is reflected by the plane mirror 6 and will illuminate the area array CCD, and because the light source rotates along with the main axis, the area array CCD surrounding the light source is required to receive the light spot information. When the pure angle swing is measured and calculated, the farthest value of the light spot deviating from the light source after the main shaft rotates stably should be taken.

Further, theoptical sensor 2 on thereceiver 5 is a linear array CCD, and the linear array CCD and the turning tool are located at the same horizontal height.

From the above optical path analysis, it can be seen that, under the condition that the half-transmitting and half-reflectingmirror 4 is not moved, the light spot of the reflected part of the laser beam on thereceiver 5 also describes a circle, but after the cutting, the pure angle swing of the spindle is mainly affected by the cutting action force of the cutter to be increased, so that the bent spindle axis caused by the pure angle swing can be considered to be within the horizontal plane passing through the height position of the cutter, and therefore, a linear array CCD is arranged in the horizontal plane, the trouble of fitting operation of the moving track of the light spot by using the area array CCD is omitted, the distance of the light spot from the theoretical position can be directly measured, and the algorithm and the device are saved.

Further, wherein the pure angular wobble error θ = arctg (lh/(L + L), the pure radial run-out E = E ± htg θ,

in the formula: l is the distance from theemitter 1 to thehalf mirror 4;

l is the distance from theemitter 1 to the flat mirror 6;

h is the distance from thehalf mirror 4 to thereceiver 5;

and E is the deviation value from the initial position measured by the linear array CCD.

The geometric optical paths of fig. 3-4 are analyzed to obtain an error value calculation formula.

In the above calculation formula, the sign value is determined by thereceiver 5 being mounted on the same side or on the opposite side of thetool holder 8.

Further, thereceiver 5 and thehalf mirror 4 are disposed on thecenter frame 9, and the flat mirror 6 is disposed on thetailstock 10.

Referring to fig. 5, a pure angle swing error, which greatly affects the spindle accuracy, generally occurs during the process of turning the outer circle. In the middle of the practical use, the end face can be turned firstly after the workpiece blank is clamped, then theemitter 1 is adsorbed on the end face of the workpiece through the magnet, and the detection can be started without centering.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims (9)

1. A lathe rotation error detection monitoring device is installed on a lathe and used together with the lathe, and is characterized by comprising:

a main controller;

the emitter can be arranged on the lathe and coaxially rotates with the lathe spindle, the emitter is provided with a front surface and a back surface which are parallel, the back surface faces the lathe spindle, the front surface is provided with a light sensor, the center of the light sensor is provided with a fine hole, a laser light source is arranged in the hole, and laser light rays are emitted outwards at an angle vertical to the front surface; the emitter is communicated with the main controller and can transmit incident light received by the light sensor to the main controller;

the reflector comprises a semi-transparent semi-reflecting mirror with a mirror surface forming an included angle α with the laser ray, and the semi-transparent semi-reflecting mirror is positioned on the laser ray light path;

the receiver is provided with a light sensor positioned on a reflection light path of the semi-transparent semi-reflector and is communicated with the main controller;

the plane mirror is arranged on a transmission light path of the laser light penetrating through the semi-transparent semi-reflecting mirror, and the mirror surface is vertical to the laser light;

when the detection is carried out, a laser light source on the emitter finds laser light, part of the light penetrates through the semi-reflecting and semi-transmitting mirror to shine on the plane mirror, the light is reflected back to the light sensor on the emitter to be received, and the other part of the light is reflected by the semi-reflecting and semi-transmitting mirror to be received by the light sensor projected on the receiver.

2. The turning error detection monitoring device for a lathe according to claim 1, wherein: the included angle between the semi-transparent and semi-reflective mirror surface of the reflector and the emitted laser light is 45 degrees.

3. The turning error detection monitoring device for a lathe according to claim 1, wherein: the back of the emitter is provided with a magnet which can be adsorbed on a main shaft mechanism or a clamped workpiece end, and the light source of the emitter is substantially on the main shaft axis.

4. The turning error detection monitoring device for a lathe according to claim 1, wherein: the transmitter is provided with a battery and communicates with the controller in a wireless manner.

5. The turning error detection monitoring device for a lathe according to claim 1, wherein: the controller is connected to an electric cabinet of the lathe, can monitor and read voltage and current information of the lathe during operation, and judges whether the lathe is in a no-load state or a cutting state according to the change of the actual power of the lathe.

6. The turning error detection monitoring device for a lathe according to claim 1, wherein: the light sensor on the emitter is an area array CCD.

7. The turning error detection monitoring device for a lathe according to claim 6, wherein: the optical sensor on the receiver is a linear array CCD, and the linear array CCD and the turning tool are positioned at the same horizontal height.

8. The turning error detection monitoring device for a lathe according to claim 7, wherein: wherein the pure angular wobble error θ = arctg (lh/(L + L), the pure radial run-out E = E ± htg θ,

in the formula: l is the distance from the emitter to the half-mirror;

l is the distance from the emitter to the plane mirror;

h is the distance from the half-transmitting and half-reflecting mirror to the receiver;

and E is the deviation value from the initial position measured by the linear array CCD.

9. The turning error detection monitoring device for a lathe according to claim 1, wherein: the receiver and the semi-transparent semi-reflecting mirror are arranged on the center frame, and the plane mirror is arranged on the tailstock.

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