CN112720366A - Hand tool - Google Patents

Abstract

A hand tool includes a hammer impact mechanism, and a mode adjustment mechanism that is switchable between a drill mode and an impact mode. The hammer impact mechanism comprises a ram, a guide piece and an energy storage mechanism, and a curved surface guide part and a conversion piece are arranged between the ram and the guide piece; in the impact mode, the tool spindle can be operatively moved from an initial position to a working position, and when the spindle is in the initial position, the curved surface guide part can not drive the hammer to axially move through the conversion part; when the tool spindle is in a working position, the curved surface guide part can drive the hammer to overcome the acting force of the energy storage mechanism to axially move towards a first direction through the conversion part; an energy storage mechanism can drive the ram to move axially in a second direction opposite the first direction to impact the tool spindle. According to the invention, the position of the cutter spindle can be moved when bearing a load, so that the hammer is controlled to impact the cutter spindle, unnecessary noise is avoided, and better operation experience is provided for a user.

Description

Hand tool

Technical Field

The invention relates to the technical field of percussion drilling, in particular to a handheld tool.

Background

In the field of percussion drilling technology, a rotary striking mechanism is driven by a motor as a driving source to provide rotation and striking to a gun drill, thereby intermittently transmitting a rotary striking force to a tip tool in order to perform an operation such as tightening a screw. In the related art, an active percussion structure is mounted on a common gun drill to form a percussion drill mode, and the gun drill is complex in operation process and complex in mode switching operation. The existing percussion drill starts a motor in a percussion mode, and no matter whether a working head of the percussion drill or a cutter main shaft bears external load or not, a hammer in a percussion mechanism can strike the cutter main shaft to generate noise.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. To this end, the invention proposes a handheld tool that provides a better operating experience for the user.

A hand tool according to an embodiment of the invention comprises: a housing; a motor disposed on the housing; the machine core comprises a transmission device driven by the motor to rotate, a hammer impact mechanism, a cutter spindle at least partially extending out of the machine shell and a mode adjusting mechanism; the tool spindle is used for connecting a tool; the transmission device is used for transmitting the rotary motion of the motor to the tool spindle; the mode adjustment mechanism is operable to transition the hand tool between at least a drilling mode and an impact mode; the hammer impact mechanism comprises a hammer and a guide piece which can rotate relatively, and an energy storage mechanism which is abutted against the hammer, wherein one of the hammer and the guide piece is provided with a curved surface guide part, and the other of the hammer and the guide piece is provided with a conversion piece; in an impact mode, the tool spindle is operable to move from an initial position to a working position, and when the tool spindle is in the initial position, the curved guide cannot drive the hammer to move axially through the conversion piece; when the tool spindle is in a working position, the curved surface guide part can drive the hammer to overcome the acting force of the energy storage mechanism to axially move towards a first direction through the conversion part; the energy storage mechanism can drive the hammer to axially move towards a second direction opposite to the first direction so as to impact the tool spindle.

According to the hand tool of the embodiment of the invention, the tool spindle is connected with the hammer in a non-relative rotation manner, and the tool spindle drives the hammer to rotate relative to the guide piece.

In the embodiment of the invention, the guide piece is sleeved on the outer side of the hammer, the curved surface guide part is arranged on the outer peripheral wall of the hammer, the conversion piece is arranged between the guide piece and the curved surface guide part, and the curved surface guide part extends along the first rotation direction on the outer peripheral surface of the hammer in a spiral line shape. When the tool spindle is in the working position, the conversion piece is positioned on a first side of the curved surface guide part far away from the motor, and when the hammer is driven by the motor rotating along the first direction to rotate relative to the guide piece, the hammer is driven by the conversion piece to move axially; when the tool spindle is in the initial position, the conversion piece is positioned on the second side of the curved surface guide part close to the motor, and when the hammer rotates relative to the guide piece, the hammer does not axially move relative to the conversion piece. When the tool spindle is in a working position and the motor rotates along a first direction to drive the hammer to rotate, the conversion piece abuts against the first side surface of the curved surface guide part and drives the hammer to move axially; when the tool spindle is in the initial position, the conversion piece is separated from the second side surface of the curved guide part.

In some embodiments, the conversion member is located on a second side of the curved guide portion adjacent the motor when the motor rotationally drives the ram in rotation in a second direction opposite the first direction when the tool spindle is in the working position, the ram being free of axial movement.

In some embodiments, when the tool spindle is in the home position, the ram and the guide cannot rotate relative to each other; when the tool spindle is in the working position, the ram can thus be driven in rotation by the motor relative to the guide.

In some embodiments, the transmission is disconnected when the tool spindle is in the home position; the transmission establishes a connection when the tool spindle is in the working position.

In some embodiments, the transmission includes a first clutch coupled to the motor, and a second clutch coupled to the ram; when the tool spindle is in the initial position, the first clutch is separated from the second clutch; the first clutch engages the second clutch when the tool spindle is in the operating position, thereby enabling the rotational movement of the motor to be transmitted to the ram.

In some embodiments, the first clutch and the first clutch are provided as a one-way transmission mechanism capable of driving rotation of the hammer upon rotation of the motor in a first direction when the first clutch is engaged with the second clutch; when the motor rotates in a second direction opposite to the first direction, the hammer cannot be driven to rotate by the one-way transmission mechanism.

In some embodiments, the first clutch is configured as a first ratchet member, the second clutch is configured as a second ratchet member, the transmission device includes a gear wheel, the first ratchet member is fixedly disposed relative to the gear wheel, the hammer impact mechanism includes an impact shaft sleeved on the tool spindle, the second ratchet member is fixedly disposed relative to the impact shaft, and the hammer is connected to the impact shaft in a non-relative rotation manner.

In some embodiments, the hammer impact mechanism comprises an impact shaft for driving the hammer to rotate, a clutch is arranged between the impact shaft and the hammer, the clutch has a first state and a second state, when the tool spindle is in the initial position, the clutch is in the first state, and the hammer cannot rotate relative to the guide piece; when the tool spindle is in the working position, the clutch is in the second state and the ram is able to rotate relative to the guide.

In some embodiments, the clutch comprises a movably arranged clutch piece, a groove body arranged on the impact shaft and a containing groove arranged on the hammer; when the clutch is in a first state, the clutch piece is separated from the containing groove of the hammer; when the clutch is in the second state, the clutch part is meshed in the containing groove of the hammer and the groove body of the impact shaft, so that the impact shaft and the hammer are connected together in a non-relative-rotation mode, and the impact shaft can transmit rotary motion to the hammer.

In the impact mode, when the working head or the cutter spindle does not bear external load, the cutter spindle does not axially move, and even if the motor is started, the hammer impact mechanism does not generate impact, so that noise is not generated, and better operation experience is provided for users.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a perspective view of a hand tool according to a first embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of a hand tool according to a first embodiment of the present invention;

FIG. 3 is a perspective view of a partial structure of a hand tool according to a first embodiment of the present invention;

FIG. 4 is an exploded perspective view of a portion of the hand tool of FIG. 3;

FIG. 5 is an exploded perspective view of the mode adjustment mechanism according to the hand tool of FIG. 3;

FIG. 6 is a schematic perspective view of a mode adjustment mechanism according to the hand tool of FIG. 3;

FIG. 7 is a cross-sectional schematic view of the mode adjustment mechanism of FIG. 5 with the stop in a first position;

FIG. 8 is a cross-sectional schematic view of the mode adjustment mechanism of FIG. 5 with the stop in a second position;

FIG. 9(a) is a cross-sectional schematic view of the hand tool of FIG. 3, the hand tool being in a drill mode with the stop in a first position, wherein the stop blocks the cutter main shaft from moving in the motor direction;

FIG. 9(b) is a schematic cross-sectional view of the hand tool of FIG. 3, the hand tool being in an impact mode wherein the stop is in a second position allowing the main shaft of the cutter to move closer to the motor, while the motor is rotating in a forward direction;

FIG. 9(c) shows the spindle of FIG. 9(b) moving further, with the spring seat separated from the circlip;

FIG. 9(d) is the hammer charging extreme position of the hand tool in impact mode of FIG. 3;

FIG. 9(e) is the view of FIG. 3 with the hand tool in the impact mode with the ram striking the tool spindle by the energy charging mechanism;

FIG. 10(a) is a schematic view of the hand tool of FIG. 9(a) in a drill mode with the transition piece separated from the ram;

FIG. 10(b) is a schematic view showing the state in which the conversion member comes into abutment with the curved surface guide portion of the hammer in the impact mode of the hand tool shown in FIG. 9 (b);

FIG. 10(c) is a schematic view of the hand tool of FIG. 9(c) in an impact mode with the transition piece moved against the curved ram guide;

FIG. 10(d) is a schematic view of the hand tool of FIG. 9(e) in an impact mode with the ram separated from the curved surface guide of the ram after the ram impacts the tool spindle at one time;

FIG. 11(a) is a cross-sectional schematic view of the hand tool of FIG. 3, the hand tool being in an impact mode with the stop in a second position allowing the cutter main shaft to move in a motor direction;

FIG. 11(b) shows the case where the main axis of the tool moves closer to the motor and the switching member drives the hammer to move away from the motor when the motor is rotated in the reverse direction in FIG. 11 (a);

FIG. 12(a) is a view showing the positional relationship between the conversion member and the hammer in FIG. 11(a), when the conversion member is away from the curved-surface hammer guide portion;

FIG. 12(b) is a view of the positional relationship between the conversion member and the ram of FIG. 11(b), with the conversion member in back contact with the curved ram guide portion;

FIG. 13 is an exploded perspective view of a partial structure of a hand tool according to a second embodiment of the present invention;

FIG. 14 is an exploded perspective view of the mode adjustment mechanism of FIG. 13;

FIG. 15 is a schematic view, partially in section, of the mode adjustment mechanism of FIG. 13 with the lock knob in a second position;

FIG. 16 is a schematic view of a hand tool according to a second embodiment of the present invention in a drill mode with the tool spindle, the mode adjustment mechanism and the hammer impact mechanism in position;

FIG. 17a is a schematic view of the position of the tool spindle upon initial axial movement of the tool spindle under an external force, the mode adjustment mechanism and the hammer impact mechanism in the impact mode of the hand tool in accordance with the second embodiment of the present invention;

FIG. 17b is a schematic view of the hammer impact mechanism of FIG. 17a with the tool spindle axially moved to an extreme position by an external force;

FIG. 18a is a schematic view of the hand tool according to the third embodiment of the present invention in a drill mode with the tool spindle, the mode adjustment mechanism and the hammer impact mechanism in position;

fig. 18b is a schematic view of the position of the tool spindle, mode adjustment mechanism and hammer impact mechanism of the hand tool of fig. 18a in an impact mode.

Reference numerals:

hand tool 100,movement 101,casing 110,handle 1101,switch assembly 1102,chuck 112,gear box 113,guide 114,support washer 115,large gear 116,snap spring 117,ejection spring 118,compression spring seat 119,motor 120,tool spindle 130, front bearing 131,step 132,rear bearing 133,transmission 140,clutch 141,first ratchet 1411,second ratchet 1412,mode adjustment mechanism 150,operation member 151,lock button 1511,operation button 1512,compression spring 1513,seal 1514,collar 1515,stop projection 1516,groove 1517,stop 152,first end 1521,second end 1522,pivot 1523,elastic member 153,hammer impact mechanism 160,hammer 161,curved surface 1611,recess 1612,guide 162,conversion member 1621,energy storage mechanism 1622, one-way transmission mechanism 163,impact shaft 1632,transmission 1633, receiving portion 1623,middle cover 170,receiving chamber 171, abaffle 180.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

Referring now to fig. 1-4, thehand tool 100 according to the present invention can be selectively operated in a drill mode or an impact mode, so that thehand tool 100 can be used for drilling holes in hard materials such as concrete.

Ahandheld tool 100 according to an embodiment of the invention, comprises: ashell 110, amotor 120 arranged in the shell, and amovement 101; themovement 101 includes atransmission 140 driven to rotate by amotor 120, ahammer impact mechanism 160, and atool spindle 130 at least partially protruding from thehousing 110 and amode adjustment mechanism 150; themotor 120, thetransmission 140, and thehammer impact mechanism 160 are housed in ahousing 110, thehousing 110 includes ahandle 1101 for a user to hold and operate, and aswitch assembly 1102 is disposed on thehandle 1101 for controlling the rotation of themotor 120; thehammer impact mechanism 160 is accommodated in thegear housing 113, thechuck 112 is connected to the front end of thetool spindle 130 extending out of thegear housing 113, and thechuck 112 is used to clamp a tool.

In particular, themotor 120 is connected to atransmission 140, thetransmission 140 being used to transmit the rotational movement of themotor 120 to thetool spindle 130. As used herein, "coupled" may refer to themotor 120 being directly coupled to thetransmission 140, e.g., the output of themotor 120 may be directly coupled to an end of thetransmission 140, and "coupled" may also refer to themotor 120 being indirectly coupled to thetransmission 140, e.g., themotor 120 may be directly coupled to an intermediate transmission assembly and then directly coupled to thetransmission 140 via the intermediate transmission assembly.

Thehammer impact mechanism 160 includes a relativelyrotatable hammer 161, aguide 114, and anenergy accumulating mechanism 1622 abutting thehammer 161. Wherein, one of thehammer 161 and theguide member 114 is provided with a curvedsurface guide part 1611, and the other of thehammer 161 and theguide member 114 is provided with aconversion member 1621, in the impact mode, when thehammer 161 rotates relative to theguide member 162, the curvedsurface guide part 1611 drives thehammer 161 to move towards the first direction by overcoming the acting force of theenergy storage mechanism 1622 through theconversion member 1621; theenergy storage mechanism 1622 drives theram 161 in a second direction opposite the first direction to impact thetool spindle 130.

It should be noted that, in the embodiment of the present invention, in thehandheld tool 100, in the impact mode, theguide 114 is disposed as a support ring and fixed relative to thehousing 110, thehammer 161 is disposed inside the support ring and is driven by the motor 11 to rotate relative to theguide 114, thecurved guide 1611 is disposed on the outer side surface of thehammer 161, and theconversion element 1621 is disposed inside theguide 114 and between thehammer 161 and theguide 114; to facilitate the assembly oftool spindle 130, and to allowtool spindle 130 to rotate and move axially relative tohousing 110, the front and rear ends oftool spindle 130 are supported byfront bearing 131 andrear bearing 133, respectively.

Referring to fig. 3 and 4, thetool spindle 130 may be a three-section structure, the front end of which is a connecting portion for connecting thechuck 112 and supported by thefront bearing 131 and installed in thegear box 113; the middle part comprises astep 132 extending in the radial direction and a transmission part, a force bearing surface facing themotor 120 is arranged on thestep 132 and is used for receiving the impact of theram 161, so as to drive thetool spindle 130 to move along the axial direction of the tool spindle and further enable thechuck 112 connected to thetool spindle 130 to generate impact; the rear portion of thetool spindle 130 is a transmission portion for receiving a rotational torque from themotor 120. The middle of thetool spindle 130 is also provided with a clampinggroove 117a, theclamp spring 117 is fastened in the clampinggroove 117a, thetool spindle 130 is sleeved with apressure spring seat 119, thepressure spring seat 119 is located on one side, close to thestep 132, of theclamp spring 117, and theclamp spring 117 is used for limiting axial displacement of thepressure spring seat 119; theram 161 is sleeved on the transmission part of thetool spindle 130 in a clearance fit manner, one side of theram 161 facing themotor 120 is recessed to form an accommodating cavity for accommodating anenergy storage mechanism 1622, theenergy storage mechanism 1622 can be a pressure spring, one end of theenergy storage mechanism 1622 abuts against the side wall of the accommodating cavity of theram 161, and the other end abuts against thepressure spring seat 119; the other side of thepressure spring seat 119 opposite to theenergy storage mechanism 1622 is provided with a jackingspring 118.

When themotor 120 rotates in the forward direction, thehammer 161 is driven by thetool spindle 130 to rotate in the forward direction, and thecurved guide 1611 is engaged with theguide 162, so that the movement path of thehammer 161 can be controlled, and the movement path can not only allow thehammer 161 to rotate around the circumferential direction of thetool spindle 130, but also allow thehammer 161 to move along the axial direction of thetool spindle 130, so that thehammer 161 can strike thetool spindle 130, and thechuck 112 and the tool clamped by the chuck can drill a workpiece surface by impact.

Preferably, in order to make thehammer 161 generate the required hammering force when hitting thetool spindle 130, the weight of thehammer 161 is 10% or more of the sum of the weights of thetool spindle 130, and in order to make the tool not too heavy and make the entire machine compact, the weight of thehammer 161 is 60% or less of the sum of the weights of thetool spindle 130. More preferably, the weight of theram 161 is 35% or less of the sum of the weight of thetool spindle 130.

As shown in fig. 3 and 4, a plurality of inclined ribs, namely,curved guide portions 1611, extend radially from the outer surface of thehammer 161. In this embodiment, two ribs are symmetrically disposed on the outer surface of thehammer 161, and the twoconversion members 1621 are steel balls and symmetrically received in the grooves of the support ring.

As shown in fig. 4 and 9a, thetransmission device 140 includes alarge gear 116 driven by themotor 120, and the rear portion of thetool spindle 130 is coupled to thelarge gear 116 through a spline or a flat square for transmitting the rotation torque of themotor 120 to thetool spindle 130. Thelarge gear 116 is formed with a recess for mounting a mode switching mechanism and arear bearing 133 to support and fix thehammer impact mechanism 160. One end of theejection spring 118 abuts against thepressure spring seat 119, and the other end abuts against thelarge gear 116.

In accordance with thehand tool 100 of an embodiment of the present invention, themode adjustment mechanism 150 is operable to transition thehand tool 100 between a drill mode and an impact mode. By operating themode adjustment mechanism 150, the operating state of thehammer 161 can be controlled, so that it is possible to control whether thehammer 161 has a striking effect on thetool spindle 130, so that it is possible to control whether thetool spindle 130 has a movement in the axial direction, and thus it is possible to switch thehand tool 100 between the impact mode and the drilling mode.

Referring to fig. 5 and 6, themode adjustment mechanism 150 includes an operatingmember 151 movably disposed with respect to thehousing 110, and astopper 152 associated with the operatingmember 151, the operatingmember 151 being operable to drive thestopper 152 between a first position and a second position. FIG. 7 shows that when stop 152 is in the first position, stop 152 prevents axial movement oftool spindle 130 towardmotor 120 andhand tool 100 is in the drill mode; when stop 152 is in the second position, as shown in fig. 8, stop 152 allows axial movement oftool spindle 130 towardmotor 120, andhand tool 100 is in the impact mode.

Thehandheld tool 100 comprises amiddle cover 170 fixedly arranged relative to thehousing 110, themiddle cover 170 is provided with anaccommodating cavity 171 and anaccommodating part 1524 communicated with theaccommodating cavity 171, theaccommodating part 1524 can allow thecutter spindle 130 to extend into theaccommodating part 1524, abaffle 180 is arranged on the rear side of theaccommodating part 1524 and used for limiting the movement of thecutter spindle 130, and thestop part 152 is accommodated in theaccommodating cavity 171. According to some embodiments of the present invention, theoperation member 151 is rotatably disposed with respect to thehousing 110. Thestopper 152 has afirst end 1521 abutting against the operatingmember 151 and asecond end 1522 overlapping the receivingportion 1524, and thepivot 1523 is located between thefirst end 1521 and thesecond end 1522. In some embodiments,mode adjustment mechanism 150 further includes aresilient member 153 that biases stop 152 toward the first position, and operatingmember 151 against the force ofresilient member 153 can move stop 152 from the first position to the second position. To facilitate the abutment of thefirst end 1521 of thestopper 152 with the operatingmember 151, the operatingmember 151 has astopper projection 1516.

According to some embodiments of the present invention, thestopper 152 has a rod shape, and the operatingmember 151 drives thestopper 152 to rotate around thepivot 1523 between the first position and the second position. When stop 152 is in the first position, stop 152overlaps pocket 1524 to prevent axial movement oftool spindle 130 towardmotor 120 intopocket 171, and when stop 152 is in the second position, stop 152 is misaligned withpocket 1524 to allow axial movement oftool spindle 130 from the home position towardmotor 120 from the working position intopocket 1524. Themiddle cover 170 is a part of the gear housing and is an end cover structure adjacent to thehammer impact mechanism 160. The rear end of thetool spindle 130 is provided with a tapered groove, a steel ball is arranged in the tapered groove, and the arrangement of the steel ball enables the rotational friction between thetool spindle 130 and thestop member 152 to be reduced when thetool spindle 130 abuts against thestop member 152.

Fig. 9a to 9d show different positions oftool spindle 130,mode adjustment mechanism 150, and hammerimpact mechanism 160 in different states ofhand tool 100, wherein: FIG. 9a showsmode adjustment mechanism 150 in a first state whenhand tool 100 is in the drill mode, i.e., stop 152 is in a firstposition overlapping pocket 1524 to prevent axial movement oftool spindle 130 in the direction ofmotor 120; when thetool spindle 130 is subjected to external abutting acting force due to the chuck and the tool, thetool spindle 130 cannot generate axial displacement in the direction close to themotor 120 due to the resistance of thestopper 152, and the tail end of thetool spindle 130 abuts against thestopper 152 through a steel ball; fig. 10a shows theconversion piece 1621 separated from thecurved guide 1611 when thetool spindle 130 is in the initial position.

Fig. 9 b-9 d illustrate whenhand tool 100 is in the impact mode, whereinmode adjustment mechanism 150 is in the second state, i.e., stop 152 is in a position offset from receivingportion 1524 to allow axial movement oftool spindle 130 towardmotor 120 to the working position. Fig. 9b shows that when thetool spindle 130 moves in the direction indicated by the arrow M under the action of an external load when the startingmotor 120 rotates in the first direction, theram 161, theenergy storage mechanism 118 and thespring seat 119 move integrally with thetool spindle 130, and theejection spring 118 is compressed until thespring seat 119 abuts against thelarge gear 116; the external load is now less than the force of theenergy storage mechanism 118; fig. 10b shows that when thetool spindle 130 is in the working position, theconversion member 1621 is located on the first side of the curved surface guide portion away from themotor 120, thehammer 161 is driven by thetool spindle 130 to rotate in the first direction indicated by the arrow a, theconversion member 1621 abuts against theside surface 1611a of the curvedsurface guide portion 1611 facing thechuck 112, theconversion member 1621 starts to climb along the curvedsurface guide portion 1611, and thehammer 161 is driven by theconversion member 1621 to move axially.

As shown in fig. 9c, as the external load increases with further movement of thetool spindle 130, thespring seat 119 is separated from thesnap spring 117; fig. 10c shows theconversion piece 1621 correspondingly climbing further along thecurved guide 1611. Theconversion element 1621 drives theram 161 against the force of theenergy storage mechanism 118 in the direction of the motor, so that theenergy storage mechanism 118 stores energy in compression.

As shown in fig. 9d, theconversion element 1621 drives theram 161 against the force of theenergy storage mechanism 118 in the direction of the motor until it abuts against thestop plate 180, at which time theenergy storage mechanism 118 stores the maximum energy. When fig. 10d shows theconversion member 1621 climbing to the bottom of thecurved guide 1611 and separating from thecurved guide 1611. Once theconversion element 1621 is separated from thecurved guide 1611, theenergy storage mechanism 118 starts to move and return in the direction indicated by the arrow M1, which is opposite to the direction indicated by the arrow M1.

As shown in fig. 9e, when theenergy storage mechanism 118 is reset, thetool spindle 130, thespring seat 119 and thesnap spring 117 are restored to abut against each other, and the hammer 16 is driven by theenergy storage mechanism 118 to rapidly move in the direction shown by the arrow M1 in fig. 9d to strike the force bearing surface on thestep 132 of thetool spindle 130.

Thehand tool 100 requires the motor to rotate in the forward direction during normal drilling operations; when a drilling operation is required to be performed, the cutter needs to be pulled out of the hole first and then the next drilling operation is performed, at this time, the motor is required to drive the cutter to rotate in the reverse direction due to the frictional resistance between the cutter and the workpiece, and the cutter is easy to pull out of the hole, so that the motor is required to rotate forwards and backwards, and the drilling tool is a functional requirement on a handheld tool, particularly a drilling tool. However, for a hand tool with a percussion function, the percussion function is an undesirable function when the motor is rotated in the reverse direction.

Referring to fig. 11a and 11b, the hand tool is in the impact mode, the guide is fixed relative tohousing 110, stop 152 is pivoted aboutpivot 1523 to the second position, andtool spindle 130 is allowed to move axially in the direction of arrow M from the home position to the work position under the force of an external load. When thetool spindle 130 is in the home position, theconversion member 1621 is located on the second side of the curved guide portion near themotor 120, and when theram 161 is driven to rotate relative to the guide member by thetool spindle 130, theram 161 does not move axially relative to theconversion member 1621.

When themotor 120 rotates in the reverse direction, theconversion member 1621 cannot engage with thecurved guide 1611. As shown in fig. 12a and 12b, thehammer 161 is driven by themotor 120 to rotate in the reverse direction indicated by the arrow b, and when thehammer 161 rotates to a certain angle, theconversion member 1621 abuts against the back surface of thecurved guide 1611. Thus, as thehammer 161 further rotates, theconversion member 1621 further moves along the back surface of thecurved guide 1611 and applies a force in the direction indicated by the arrow f to the back surface of thecurved guide 1611, and thehammer 161 is driven to move axially in the direction indicated by the arrow M1 by the force, rather than being driven by the force of theenergy accumulating mechanism 118. That is, thehammer 161 is driven by the switchingmember 1621 to move in the reverse direction until it abuts against the force-receiving surface on thestep 132. Thehammer 161 cannot rapidly impact thetool spindle 130, and thus it is possible to realize that thehammer impact mechanism 160 does not impact thetool spindle 130 when the motor of thehand tool 100 is reversely rotated. In addition, if the curved surface guide portion is to be avoided from being provided with the linear slope, the rotation blockage is easily generated between the steel ball and the linear slope. Due to the arc arrangement of thecurved guide 1611, theconversion element 1621 rides along the arc when theram 161 rotates reversely to avoid the occurrence of rotation blockage.

As shown in fig. 13 to 15, according to the second embodiment of the present invention, in the structural layout of themovement 101a, thehammer impact mechanism 160, thetransmission device 140, and the mode adjustment mechanism all have differences from the first embodiment. Theoperation member 151a of the mode adjustment mechanism includes alock button 1511 movably disposed with respect to thehousing 110, and anoperation button 1512 connected to thelock button 1511, wherein thelock button 1511 is capable of moving between a first position and a second position with respect to thehousing 110. Thus, whenlock knob 1511 is in the first position,lock knob 1511 locks the mode adjustment mechanism relative tohousing 110 such thatstop 152 prevents axial movement oftool spindle 130 in the direction ofmotor 120; whenlock knob 1511 is in the second position,lock knob 1511 can release the mode adjustment mechanism from the locked position, allowingoperating knob 1512 to move stop 152 together such thatstop 152 is moved to a position that allows axial movement oftool spindle 130 towardmotor 120.

Further, acompression spring 1513 is provided between thelock knob 1511 and theoperation knob 1512, thecompression spring 1513 biases thelock knob 1511 to the first position, and thelock knob 1511 is pushed against the urging force of thecompression spring 1513 to move thelock knob 1511 from the first position to the second position, whereby the position lock of the phase mode adjustment mechanism on thehousing 110 can be released. For example, in the state shown in fig. 15, thelock knob 1511 is in the first position, a part of thelock knob 1511 is embedded in thegroove 1517 of thehousing 110, and thelock knob 1511 locks the mode adjustment mechanism with respect to thehousing 110; after thelock button 1511 is pressed in the direction indicated by the arrow M2, thelock button 1511 compresses thecompression spring 1513, thelock button 1511 disengages from thegroove 1517, at this time, thelock button 1517 releases the locking effect on theoperation button 1512, and theoperation button 1512 can drive thelock button 1517 to perform position switching, in this embodiment, theoperation button 1512 drives thelock button 1517 to pivot around thepivot 1523 axis of thestopper 152 together, so as to realize switching the working mode of thehandheld tool 100 by using theoperation button 1512, that is, at this time, thehandheld tool 100 can be switched between the drilling mode and the impact mode.

As shown in fig. 14, in some embodiments,lock button 1511 moves in a direction perpendicular to stop 152. In order to simplify the structure of thestopper 152, thestopper 152 may be rod-shaped and can rotate together with theoperating knob 1512 around its own axis, a receivingportion 1524 is provided on thestopper 152, and the operatingmember 151 is operable to drive thestopper 152 to rotate between the first position and the second position. Thus, when stop 152 is in the first position, receivingportion 1524 ofstop 152 is offset fromtool spindle 130 to preventtool spindle 130 from moving axially in the direction ofmotor 120 into receivingportion 1524. When stop 152 is in the second position, receivingportion 1524 ofstop 152 is aligned withtool spindle 130 to allowtool spindle 130 to move axially into receivingportion 1524 in the direction ofmotor 120. Further, the receivingportion 1524 may be provided in the form of a blind hole. This facilitates processing of thehousing portion 1524, and simplifies the structure of thestopper 152. In addition, in order to facilitate the engagement of thelock knob 1511 with thegroove 1517, thegroove 1517 is two spaced apart. As shown in fig. 13, thegrooves 1517 are symmetrically distributed at 180 degrees on thehousing 110, and the arrangement of thegrooves 1517 takes into consideration the blind hole position of the receivingportion 1524, that is, onegroove 1517 is used for locking thestopper 152 at the first position, so as to prevent the axial movement of the tool spindle; anothergroove 1517 is used to lockstop 152 in a second position in whichpocket 1524 is axially aligned with the tool spindle shaft, allowing the tool spindle to move axially into the blind bore.

In some embodiments, as shown in fig. 13 and 14, to facilitate theoperation knob 1512 being sleeved on thestopper 152, the mode adjustment mechanism further includes asealing ring 1514 and twocollars 1515, wherein the twocollars 1515 are sleeved on thestopper 152, and the twocollars 1515 are spaced apart along the length of thestopper 152, and theoperation knob 1512 is located between the twocollars 1515. Asealing ring 1514 is used to seal the assembly gap between thestopper 152 and theoperating knob 1512. Whereby thestopper 152 can be stably fitted with theoperation knob 1512

Referring to FIG. 16, the mode adjustment mechanism is locked with respect tohousing 110 such thatstop 152 prevents axial movement oftool spindle 130 in the direction ofmotor 120; at this point, thehand tool 100 is in the drill mode.

Referring further to fig. 13 and 16, thetransmission device 140 includes a one-way transmission mechanism 163, the one-way transmission mechanism 163 includes afirst ratchet member 1411 connected to a side of thelarge gear 116 facing thehammer impact mechanism 160, and animpact shaft 1632 sleeved on thetool spindle 130, asecond ratchet member 1412 is disposed on theimpact shaft 1632, thefirst ratchet member 1411 and thesecond ratchet member 1412 are engaged with each other, and when themotor 120 is driven to rotate in the first direction, the rotation of themotor 120 is transmitted to theimpact shaft 1632 through the one-way transmission mechanism 163. A clutch is arranged between thetool spindle 130 and theram 160, the clutch includes aclutch member 141 movably arranged, apit 1612 arranged on thetool spindle 130, a groove body arranged on theimpact shaft 1632, and anaccommodating groove 1621a arranged on theram 160, specifically, theclutch member 141 may be arranged in a ball shape or a column shape, in this embodiment, theclutch member 141 is arranged in a steel ball. The clutch has two different states, a first state and a second state.

The hand tool shown in fig. 16 is in a drill mode, the clutch is in a first state, theclutch member 141 engages therecess 1612 of thetool spindle 130 and the slot of theimpact shaft 1632, and theclutch member 141 does not transmit torque to thehammer 160, i.e. thehammer 160 does not rotate when thetool spindle 130 and theimpact shaft 1632 are driven to rotate by themotor 120.Mode adjustment mechanism 150 is also in the first state at this time, i.e.,stopper 152 is in the first position, receivingportion 1524 ofstopper 152 is offset fromtool spindle 130, andtool spindle 130 is prevented from moving axially in the direction ofmotor 120 into receivingportion 1524. Theimpact shaft 1632 is connected to thelarge gear 116 through theunidirectional transmission mechanism 163, thetool spindle 130 is connected to thelarge gear 116 through a spline, and when themotor 120 is started to rotate, thetool spindle 130 and theimpact shaft 1632 output rotational motions respectively.

Referring to fig. 17a and 17b,mode adjustment mechanism 150 is in the second state, withstop 152 in the second position, and receivingportion 1524 ofstop 152 is aligned withtool spindle 130. At this time, thetool spindle 130 can axially move in the direction of themotor 120 into the receivingportion 1524 of thestopper 152 by an external force. While thetool spindle 130 is moving axially, theclutch member 141 climbs out of therecess 1612 of the tool spindle along the slope of therecess 1612 and enters the receivinggroove 1621a of thehammer 161, so that theimpact shaft 1632 and thehammer 161 are connected together without relative rotation, theimpact shaft 1632 can transmit the rotation torque to thehammer 161 via theclutch member 141, and the clutch is in the second state. When themotor 120 is started to rotate in the first direction, the rotation of themotor 120 can be transmitted to theimpact shaft 1632 through the one-way transmission mechanism 163, so that thehammer 161 is rotated relative to theguide 162 by the clutch 141, and thehammer 161 can impact thetool spindle 130.

When themotor 120 rotates in a second direction opposite to the first direction, the first andsecond ratchet members 1411 and 1412 of the one-way transmission mechanism 163 are disengaged, and the rotational motion of the motor cannot be transmitted to thehammer 161 through theimpact shaft 1632. That is, in the impact mode, when themotor 120 rotates forward, thehammer impact mechanism 160 generates an impact on thetool spindle 130. When themotor 120 rotates in reverse, thehammer impact mechanism 160 does not impact thetool spindle 130.

Referring to fig. 18a and 18b, according to the third embodiment of the present invention, in the structural layout of the movement 101b, the hammer impact mechanism includes an impact shaft 165, the impact shaft 165 is connected with the hammer 160 in a non-relative rotation manner, that is, the impact shaft 165 can rotationally drive the hammer 160 to rotate relative to the guide; the one-way transmission mechanism 163a corresponds to a clutch mechanism, the first clutch member of the clutch mechanism is the first ratchet member 1411, and the second clutch member of the clutch mechanism is the second ratchet member 1412; the first ratchet member 1411 is provided on the large gear, and the second ratchet member 1412 is provided on the striking shaft 165, and particularly, the one-way transmission mechanism 163a is different from the second embodiment in that the first ratchet member 1411 and the second ratchet member 1412 are disengaged or separated from each other in the drill mode; the ram 160 and the impact shaft 165 are connected together in a final rotation manner through a transmission piece 1633; specifically, the transmission member 1633 is configured as a steel ball, the hammer 160 is configured with a long slot engaged with the steel ball, and when the impact shaft 165 moves axially along with the tool spindle 130, the steel ball can be engaged with the long slot of the hammer 160, so that the impact shaft 165 can rotate to drive the hammer 160 to rotate relative to the guide member.

Referring to FIG. 18b, when themode adjustment mechanism 150 is adjusted to the impact mode, thetool spindle 130 is axially moved toward themotor 120 by an external force, and thesecond ratchet member 1412 on theimpact shaft 165 moves with thetool spindle 130 to a position engaging with thefirst ratchet member 1411; when themotor 120 is rotated in the first direction, the rotation of themotor 120 is transmitted to theimpact shaft 165 and thehammer 161 via theunidirectional transmission mechanism 163a, and thehammer impact mechanism 160 impacts thetool spindle 130. When themotor 120 is moved in reverse, thehammer impact mechanism 160 does not impact thetool spindle 130.

Accordingly, in the impact mode, if themotor 120 is reversely rotated in a second direction opposite to the first direction, the first andsecond ratchet members 1411 and 1412 of the one-way transmission mechanism 163a are disengaged, so that the rotational motion of the motor cannot be transmitted to thehammer 161 through theimpact shaft 165. That is, in the impact mode, when themotor 120 rotates forward, thehammer impact mechanism 160 generates an impact on thetool spindle 130. When themotor 120 rotates in reverse, thehammer impact mechanism 160 does not impact thetool spindle 130.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (12)

1. A hand tool, comprising:

a housing;

a motor disposed on the housing;

the machine core comprises a transmission device driven by the motor to rotate, a hammer impact mechanism, a cutter spindle at least partially extending out of the machine shell and a mode adjusting mechanism;

the tool spindle is used for connecting a tool; the transmission device is used for transmitting the rotary motion of the motor to the tool spindle; the mode adjustment mechanism is operable to transition the hand tool between at least a drilling mode and an impact mode;

the hammer impact mechanism comprises a hammer and a guide piece which can rotate relatively, and an energy storage mechanism which is abutted against the hammer, wherein one of the hammer and the guide piece is provided with a curved surface guide part, and the other of the hammer and the guide piece is provided with a conversion piece;

in an impact mode, the tool spindle is operable to move from an initial position to a working position, and when the spindle is in the initial position, the curved guide cannot drive the hammer to move axially through the conversion piece; when the tool spindle is in a working position, the curved surface guide part can drive the hammer to overcome the acting force of the energy storage mechanism to axially move towards a first direction through the conversion part; the energy storage mechanism can drive the hammer to axially move towards a second direction opposite to the first direction so as to impact the tool spindle.

2. The hand tool of claim 1, wherein the tool spindle is connected for rotation with a ram, the tool spindle driving the ram to rotate relative to the guide.

3. The hand tool according to claim 2, wherein the guide member is fitted to an outer side of the hammer, the curved surface guide portion is provided on an outer peripheral wall of the hammer, and the conversion member is provided between the guide member and the curved surface guide portion extending in a spiral shape along the first rotation direction on an outer peripheral surface of the hammer.

4. The hand tool of claim 3, wherein the transition member is located on a first side of the curved guide away from the motor when the tool spindle is in the working position, the ram being driven to move axially by the transition member when the ram is rotated by the motor rotating in the first direction against the guide; when the tool spindle is in the initial position, the conversion piece is positioned on the second side of the curved surface guide part close to the motor, and when the hammer rotates relative to the guide piece, the hammer does not axially move relative to the conversion piece.

5. The hand tool of claim 4, wherein the transition piece abuts the curved guide first side surface and drives the ram to move axially when the motor rotates the ram in a first direction when the tool spindle is in the working position; when the tool spindle is in the initial position, the conversion piece is separated from the second side surface of the curved guide part.

6. The hand tool of claim 4, wherein the transition member is located on a second side of the curved guide portion adjacent the motor when the motor rotationally drives the ram in rotation in a second direction opposite the first direction when the tool spindle is in the working position, the ram being free of axial movement.

7. The hand tool of claim 1, wherein when the tool spindle is in the home position, the ram and the guide are not rotatable relative to each other; when the tool spindle is in the working position, the ram can thus be driven in rotation by the motor relative to the guide.

8. The hand tool of claim 7, wherein the transmission is disconnected when the tool spindle is in the home position; the transmission establishes a connection when the tool spindle is in the working position.

9. The hand tool of claim 8, wherein the transmission includes a first clutch coupled to the motor and a second clutch coupled to the ram; when the tool spindle is in the initial position, the first clutch is separated from the second clutch; the first clutch engages the second clutch when the tool spindle is in the operating position, thereby enabling the rotational movement of the motor to be transmitted to the ram.

10. The hand-held tool of claim 9, wherein the first clutch and the first clutch are configured as a one-way transmission mechanism capable of driving rotation of the hammer upon rotation of the motor in a first direction when the first clutch is engaged with the second clutch; when the motor rotates in a second direction opposite to the first direction, the hammer cannot be driven to rotate by the one-way transmission mechanism.

11. The hand-held tool according to claim 10, wherein the first clutch is configured as a first ratchet member, the second clutch is configured as a second ratchet member, the transmission device comprises a gear wheel, the first ratchet member is fixedly disposed relative to the gear wheel, the hammer impact mechanism comprises an impact shaft sleeved on the tool spindle, the second ratchet member is fixedly disposed relative to the impact shaft, and the hammer is connected with the impact shaft in a non-relative rotation manner.

12. The hand tool of claim 7, wherein the hammer impact mechanism includes an impact shaft for driving rotation of a ram, a clutch being disposed between the impact shaft and the ram, the clutch having a first state and a second state, the clutch being in the first state when the tool spindle is in the home position, the ram being unable to rotate relative to the guide; when the tool spindle is in the working position, the clutch is in the second state and the ram is able to rotate relative to the guide.

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