CN210998534U - Impact tool - Google Patents

Abstract

The utility model provides an impact tool, which comprises a motor, a tool main shaft, an impact mechanism, a transmission mechanism and a chuck component; the impact mechanism comprises a ram and a guide piece, and the ram can axially impact the tool spindle when rotating relative to the guide piece; the chuck component is provided with a chuck body connected with the tool spindle, a plurality of clamping jaws arranged in the chuck body in a penetrating way, a locking nut locked with the clamping jaws and a rotation stopping device which enables the clamping jaws to be prevented from loosening at a locking position; the rotation stopping device comprises a rotation stopping part and a stopping claw which does not rotate relative to the locking nut and is matched and connected with the rotation stopping part. The utility model discloses can solve because the impact motion leads to the chuck to appear from the pine phenomenon, guarantee that the chuck can be by stable locking.

Description

Impact tool

Technical Field

The utility model relates to an impact tool field especially relates to an impact tool.

Background

It is known that, in use of impact tools, the collet is subjected to impact vibrations. The collet will thus self-loosen, causing the tool to be removed from the collet.

SUMMERY OF THE UTILITY MODEL

Based on aforementioned prior art defect, the embodiment of the utility model provides an impact tool, it can solve because the motion of impact leads to the chuck to appear from the pine phenomenon, guarantees that the chuck can be by stable locking.

In order to achieve the above object, the present invention provides the following technical solutions.

An impact tool, comprising:

a housing;

a motor housed in the housing;

a tool spindle rotationally driven by a motor and having a central axis;

the impact mechanism is positioned between the motor and the tool spindle and is used for transmitting impact on the tool spindle in the axial direction of the tool spindle; the method comprises the following steps: the energy storage device comprises a ram, a guide piece, a first guide piece arranged on the ram, a second guide piece arranged on the guide piece and an energy storage element abutted against the ram; when the hammer rotates relative to the guide piece, the first guide piece and the second guide piece are matched to drive the hammer to move along the central axis in a first direction against the acting force of the energy storage element, and the energy storage element can drive the hammer to move along the central axis in a second direction opposite to the first direction so as to impact the tool spindle;

a transmission mechanism for transmitting power of the motor to at least one of the hammer and the guide;

the chuck component is provided with a chuck body connected with the tool spindle, a plurality of clamping jaws arranged in the chuck body in a penetrating way, a locking nut locked with the clamping jaws and a rotation stopping device for preventing the clamping jaws from loosening at a locking position; the locking nut can drive the clamping jaw to move to a locking position by rotating along a third direction relative to the clamping jaw, the rotation stopping device comprises a rotation stopping part fixedly arranged relative to the chuck body and a stopping jaw arranged in a non-relative-rotation mode with the locking nut, and the stopping jaw is matched and connected with the rotation stopping part to prevent the locking nut from rotating along a fourth direction opposite to the third direction relative to the clamping jaw.

Preferably, the outer wall of the clamping jaw is provided with an external thread, and the locking nut is provided with an internal thread which is meshed with the external thread.

Preferably, the impact tool has at least two working modes, namely an impact mode and a non-impact mode; in the impact mode, the hammer rotates relative to the guide piece; in the non-impact mode, the hammer and the guide piece do not rotate relatively;

the impact tool further comprises a mode adjustment mechanism for switching between an impact mode and a non-impact mode, the mode adjustment mechanism being operable to switch between a first state and a second state; in a first state, the hammer can rotate relative to the guide piece, and the impact tool is in an impact mode; in a second state, the guide member is capable of being rotated by the motor and the impact tool is in a non-impact mode.

Preferably, the rotation stopping portion is disposed on an outer peripheral wall of the chuck body, and the locking pawl is sleeved outside the rotation stopping portion and has a locking end embedded in the rotation stopping portion.

Preferably, the rotation stop portion has a stop surface for engagement with the stop end, the angle between the normal direction of the stop surface and the third direction being less than 90 °.

Preferably, the stop surface is parallel to the impact direction of the impact mechanism; the stop end is pressed against the stop surface when being embedded into the rotation stop part; or the stopping end is hook-shaped, and the stopping end is hooked with the stopping surface when being embedded into the rotation stopping part.

Preferably, the rotation stopping part is a ratchet or a blind hole, and the blind hole is obliquely arranged towards the third direction.

Preferably, the latch claw has elasticity that gives the latch end a tendency to spring radially outward; the bounce direction of the stop end is perpendicular to the impact direction of the impact mechanism.

Preferably, the chuck body is externally provided with an outer sleeve capable of rotating circumferentially, and the locking pawl is arranged in the outer sleeve; a release groove is formed on the inner wall of the outer sleeve in a concave mode, and a contact bulge is formed outwards in the radial direction at the position, close to the stopping end, of the stopping claw; when the outer sleeve rotates to the position that the release groove corresponds to the contact protrusion, the contact protrusion is embedded into the release groove, and the stop end bounces to be separated from the rotation stop part.

Preferably, when the outer sleeve rotates until the release groove is staggered with the contact protrusion, the contact protrusion is contacted with the inner wall of the outer sleeve, and the stop end is pressed down to be embedded into the rotation stop part; the length of the release groove in the circumferential direction is greater than the length of the contact protrusion in the circumferential direction; the two ends of the release groove along the circumferential direction are in smooth transition with the inner wall of the outer sleeve, and the two ends of the contact protrusion along the circumferential direction are in smooth transition with the locking claws.

Preferably, the inner wall of the outer sleeve is concavely provided with a first limiting groove, and the stopping claw is provided with a limiting bulge which is outward along the radial direction; when the release groove is staggered with the contact protrusion, the limit protrusion is embedded into the first limit groove.

Preferably, the inner wall of the outer sleeve is concavely formed with a second limiting groove, and when the contact protrusion is embedded in the release groove, the limiting protrusion is embedded in the second limiting groove.

Preferably, the lengths of the first limiting groove and the second limiting groove in the circumferential direction are both greater than the length of the limiting protrusion in the circumferential direction.

Preferably, both ends of the contact protrusion in the circumferential direction are smoothly transited to the locking pawl, and the end portions of the first and second limit grooves facing each other are smoothly transited to the inner wall of the outer sleeve.

Preferably, the inner wall of the outer sleeve between the two limiting grooves and the inner walls of the two limiting grooves form a profiling surface, and the limiting protrusions exert a radially outward elastic force on the profiling surface when sliding on the profiling surface.

Preferably, the locking nut is sleeved with a fixing sleeve, the fixing sleeve can rotate outside the locking nut, and the locking claw and the outer sleeve are circumferentially fixed with the fixing sleeve.

Preferably, the fixing sleeve is provided with a limiting hole, and the contact protrusion is clamped in the limiting hole.

Preferably, the phase difference between the contact protrusions and the limiting protrusions along the circumferential direction is approximately 180 degrees, the number of the limiting holes is two, the contact protrusions are clamped into one limiting hole, and the limiting protrusions are clamped into the other limiting hole.

The rotation stopping part is arranged on the outer peripheral wall of the chuck body, and the locking claw fixed in the circumferential direction of the nut is locked outside the chuck body, so that the impact of the impact mechanism and the matching of the locking claw and the rotation stopping part are not in the same direction. Therefore, the stop pawl cannot be separated from the rotation stopping part due to the impact motion of the impact mechanism, and the problem that the chuck is self-loosened in the working process of the active impact tool with larger impact force is solved.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, the proportional sizes, and the like of the respective members in the drawings are merely schematic for helping the understanding of the present invention, and do not specifically limit the shapes, the proportional sizes, and the like of the respective members of the present invention. The skilled person in the art can, under the teaching of the present invention, choose various possible shapes and proportional dimensions to implement the invention according to the specific situation. In the drawings:

fig. 1 is a schematic view of an outer profile of an impact tool according to an embodiment of the present invention;

FIG. 2 is a cross-sectional structural view of a working member of the impact tool of FIG. 1;

fig. 3 is a schematic cross-sectional view of an impact tool according to an embodiment of the present invention in an impact mode;

fig. 4 is an exploded view of a stroker tool according to an embodiment of the invention;

FIG. 5 is a schematic cross-sectional view of an impact tool according to an embodiment of the present invention in a non-impact mode;

FIG. 6 is a schematic view of a tool spindle integrated with an impact structure shaft according to another embodiment;

fig. 7 is a schematic structural view of a guide of an impact tool according to an embodiment of the present invention;

fig. 8 is a schematic structural view of an impact switch of the impact tool according to the embodiment of the present invention;

FIG. 9 is a schematic cross-sectional view of the impact switch engaged with the guide in the impact mode;

FIG. 10 is a schematic configuration view when the impact switch member is separated from the guide member in the impact mode;

FIG. 11 is a schematic cross-sectional view of the impact switch member engaging the guide member in the impact mode;

FIG. 12 is a schematic configuration view when the impact switch member is separated from the guide member in the impact mode;

fig. 13 is a schematic structural view of a mode adjustment member according to an embodiment of the present invention;

FIG. 14 is an exploded view of the cartridge assembly of the impact tool of FIG. 1;

FIG. 15 is a cross-sectional structural view of a cartridge assembly of the impact tool of FIG. 1;

FIG. 16 is a perspective view of a cartridge assembly of the impact tool of FIG. 1;

FIG. 17 is a cross-sectional view of the cartridge assembly of the impact tool of FIG. 1 with the stop pawl inserted into the rotation stop;

FIG. 18 is a cross-sectional view of the cartridge assembly shown in FIG. 1 with the pawl disengaged from the rotation stop;

fig. 19 is a partially enlarged schematic view of a rotation stopper formed in the cartridge body of the impact tool shown in fig. 17 or 18, the rotation stopper being a ratchet.

Detailed Description

In order to make the technical solutions in the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall fall within the protection scope of the present invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appearing herein refer to the orientation or positional relationship indicated in the drawings, which is merely for convenience of description and simplicity of description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the invention.

Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In view of the self-loosening phenomenon of the chuck caused by the impact vibration during the use of the impact tool, those skilled in the art have devised a locking mechanism for preventing the chuck from self-loosening so as to prevent the lock nut from rotating in the loosening or shackle direction after clamping the chuck.

At present, the locking mechanism of the chuck mainly comprises a plug-in type, a friction type and a ratchet type in principle. However, the utility model discloses the people discover, among the current locking mechanism is used to the less traditional impact tool of impact force more, in the great initiative impact tool of impact force, locking mechanism still is difficult to guarantee the locking effect of preferred.

In particular, the impact force of the active impact tool is increased considerably compared to conventional impact tools, resulting in an increase in the impact vibration to which the chuck is subjected. Because the plug-in type locking mechanism is easy to have a gap when being matched and connected, the locking is easy to lose efficacy when the impact force is large. The friction type locking mechanism mainly depends on the contact friction between the locking nut and the limiting step to limit the circumferential rotation of the locking nut, but the contact friction surface between the locking nut and the limiting step is approximately vertical to the impact direction. Therefore, upon a large impact, the contact between the two is easily released, resulting in a failure of the locking. And because the ratchet tooth direction of the ratchet wheel type locking mechanism is consistent with the impact direction, the impact abrasion of the ratchet is serious, even the ratchet is broken, and the locking is invalid. In addition, the direction of the ratchet teeth is consistent with the direction of impact, and a locking elastic claw for braking the reverse rotation of the ratchet teeth is easy to bounce out of the ratchet teeth under the action of impact force, so that the locking failure can be caused.

In view of the above, embodiments of the present invention provide an impact tool, which can better solve the above problems.

As shown in fig. 1 to 5, the impact tool 100 according to the embodiment of the present invention includes at least two modes, i.e., an impact mode and a non-impact mode, and includes a housing 10, a transmission mechanism 20 disposed in the housing 10, a motor 30 disposed in the housing 10 and supplying power to the transmission mechanism 20, an impact mechanism 40 driven by the transmission mechanism 20, a tool spindle 50, and a mode switching mechanism 60.

As shown in fig. 1, a handle 101 is formed by extending the rear end of the housing 10 downward and disposed at an angle to the housing 10, and a battery pack 102 is detachably disposed at the bottom of the handle 101. The handle 101 is provided with a trigger 103, an operator can start and stop the impact tool 100 by pulling or releasing the trigger 103, and the trigger 103 can also adjust the rotating speed of the impact tool 100 according to the pressed depth.

Fig. 2 discloses the working components of the impact tool 100 housed within the housing 10. As shown in fig. 2, from right to left in the drawing, the working components include a motor 30, a transmission mechanism 20 connected to an output shaft of the motor 30 for adjusting an output rotation speed of the motor, an impact structure shaft 434 connected to the transmission mechanism 20, and an impact mechanism 40 driven by the impact structure shaft 434 to generate an impact action. The transmission mechanism 20 may be any suitable conventional structure, such as a planetary gear train, which is not limited by the embodiments of the present invention.

The tool spindle 50 is for receiving the chuck assembly 11 and has a central axis X. In impact mode, the tool spindle 50 reciprocates along its central axis X. In the non-impact mode, the tool spindle 50 does not reciprocate. The mode switching mechanism 60 is used to switch the impact tool between the impact mode and the non-impact mode. As described in further detail below.

The impact mechanism 40 includes a hammer 410, a guide 420, and an energy storage member 431 abutting against the hammer 410, wherein the hammer 410 is provided with a first guide 432, and the guide 420 is provided with a second guide 433. In the impact mode, the hammer 410 rotates relative to the guide 420, so that the first guide 432 can drive the hammer 410 to move along the central axis X toward the first direction a against the force of the energy accumulating element 431 through the second guide 433, and the energy accumulating element 431 can drive the hammer 410 to move along the central axis X toward the second direction B opposite to the first direction a to impact the tool spindle 50; in the non-impact mode, the ram 410 and the guide 420 do not rotate relative to each other. In the embodiment shown in fig. 3, the first direction a is horizontal to the right and the second direction B is horizontal to the left.

The transmission mechanism 20 serves to transmit the power of the motor 30 to at least one of the hammer 410 and the guide 420. The mode adjustment mechanism 60 is operable to switch between a first state and a second state; in a first state, the hammer 410 is able to rotate relative to the guide 420 and the impact tool is in an impact mode; in the second state, the guide member 420 can be rotated by the motor 30, but the hammer 410 and the guide member 420 do not rotate relative to each other, and the impact tool is in the non-impact mode. Therefore, the impact tool can be switched between the impact mode and the non-impact mode by operating the mode adjusting mechanism 60, the switching is convenient, and the functions of the impact tool are enriched.

There are various ways in which the operating mode adjustment mechanism 60 can change the state of relative movement of the ram 410 and the guide 420.

As shown in fig. 5, the impact mechanism 40 further includes an impact structure shaft 434 driven to rotate by the transmission mechanism 20, and when the mode adjustment mechanism 60 is in the first state, one of the guide 420 and the hammer 410 is fixed with respect to the housing 10, and the other is driven to rotate by the impact structure shaft 434; when the mode adjustment mechanism 60 is in the second state, the fixation of one of the guide 420 and the hammer 410 with respect to the housing is released and rotates with the other of the first guide 432 and the second guide 433.

Specifically, in the present embodiment, the ram 410 and the guide member 420 are driven to rotate by the impact structure shaft 434. When the mode adjustment mechanism 60 is in the first state, the guide 420 is restricted from rotating to be fixed relative to the housing 10, so that the energy accumulating element 431 can drive the hammer 410 to move along the central axis X in the second direction B to impact the tool spindle 50 when the hammer 410 is driven to rotate by the impact structure shaft 434. When the mode adjustment mechanism 60 is in the second state, the guide member 420 can be driven to rotate by the motor 30, and the hammer 410 is also rotated synchronously, so that the guide member 420 and the hammer 410 do not rotate relatively and the hammer 410 does not move axially back and forth.

In another embodiment, when the mode adjustment mechanism 60 is in the first state, the reverse situation may be true, i.e., the hammer 410 is restricted from rotating while the guide 420 is rotating, and at this time, the energy accumulating element 431 can drive the hammer 410 to move along the central axis X in the second direction B to impact the tool spindle 50. When the mode adjustment mechanism 60 is in the second state, the guide 420 and the hammer 410 rotate synchronously without relative rotation therebetween, and the hammer 410 does not reciprocate axially.

In yet another embodiment, when the mode adjustment mechanism 60 is in the first state, both the ram 410 and the guide 420 rotate. Specifically, at this time, the hammer 410 and the guide 420 have a difference in rotational speed such that there is relative rotational movement therebetween, and the hammer 410 can impact the tool spindle 50.

In the embodiment shown in fig. 5, the impingement structure shaft 434 is provided separate from the tool spindle 50. However, the impingement structure shaft 434 and the tool spindle 50 may also be integrally provided. In another embodiment, shown in fig. 6, the tool spindle 50 has a left end for receiving the chuck assembly 11, a middle portion for driving the ram 410 and the guide 420, and a right end engaged with the transmission mechanism 20 to receive power from the motor 30.

Energy accumulating element 431 may move ram 410 axially when ram 410 and guide 420 are able to rotate relative to each other. Specifically, as shown in fig. 5, the guide 420 is sleeved outside the hammer 410, the second guide 433 is disposed on an inner circumferential surface of the guide 420, and the first guide 432 is disposed on an outer circumferential surface of the hammer 410. As shown in fig. 7 and 8, the first guide 432 is a ball movably disposed on the ram 410, and the second guide 433 includes a plurality of climbing sections 4331 and falling sections 4332. As the ball passes the ramp section 4331, the ball drives the ram 410 against the force of the energy storage element 431 in the first direction a; when the ball passes the drop section 4332, the energy accumulating element 431 drives the ram 410 to move in a second direction B opposite to the first direction a to achieve the impact.

Preferably, the highest vertex of the hill climbing section 4331 is connected with the highest vertex of the fall section 4332. Further, the climbing section 4331 may be of a helical line type, the falling section 4332 may be of a linear type, and the falling section 4332 extends along the central axis X of the tool spindle 50. Preferably, in order to ensure that the hammer 410 generates a sufficient impact force to the tool spindle 50 and the impact tool is compact in volume, the climbing section 4331 has a climbing height in the axial direction of greater than 3mm and equal to or less than 15mm, preferably a climbing height of greater than or equal to 4mm and equal to or less than 12mm, and more preferably a climbing height of 10 mm. It should be noted that the "climbing height" refers to an axial distance between both ends of the climbing section 4331 on the central axis X of the tool spindle 50. When the first guide part 432 falls from the highest top point of the climbing section 4331, it may fall to the bottom of the next climbing section 4331 along the falling section 4332, or may directly fall to the bottom of the next climbing section 4331 without passing through the falling section 4332 in a manner that the movement locus is parabolic, in other words, the falling section 4332 may also be provided as a discontinuous portion disposed between the climbing section 4331 and the climbing section 4331.

Ram 410 fits over the exterior of impact structure shaft 434 and guide 420 fits over the exterior of ram 410. In order to achieve the relative rotation of the guide 420 and the hammer 410, the impact mechanism 40 further includes a support base 435 fixed in the housing 10, and a steel ball 436 supporting the guide 420 when the guide 420 rotates is further provided between the support base 434 and the guide 420. Thus, when the guide member 420 can rotate, the friction between the guide member 420 and the support base 435 is small.

As shown in fig. 5, the impact structure shaft 434 is sleeved with a baffle 4341, that is, the baffle 4341 is sleeved on the outer peripheral wall of the impact structure shaft 434, the energy storage element 431 is located between the hammer 410 and the baffle 4341, and an end of the energy storage element 431 away from the hammer 410 may be engaged with the baffle 4341. When ram 410 moves a distance toward energy storage element 431, ram 410 and stop 4341 may compress energy storage element 431. Thus, energy accumulating element 431 can exert an urging force on ram 410. The energy storage member 431 may be a spring, and one end of the spring is installed in a cavity formed in the hammer 410.

In other embodiments, the second guide 433 is a cam groove fixedly provided to the guide 420. The ball screw-moves in the cam groove, thereby achieving the reciprocating motion of the hammer 410 in the axial direction of the tool spindle 50. At this time, the hammer 410 may be fitted over the outside of the guide 420, and the first guide 432 is provided on the inner circumferential surface of the hammer 410.

In the above embodiment, the second guide 433 functions as a curved guide so that the hammer 410 can move along the curved guide when rotating relative to the guide 420. The first guide member 432 is a conversion member of the movement of the hammer 410.

Referring to fig. 3 and 4, the mode adjustment mechanism 60 includes an impact switch 610 and a mode adjustment member 620. The mode adjustment member 620 is operatively movable between a first position and a second position to enable the impact switch member 610 to engage with or disengage from the guide member 420. As shown in fig. 9 and 10, when the mode adjustment member 620 is at the first position, the impact switch member 610 is engaged with the guide member 420, the guide member 420 is fixed with respect to the housing 10, and the impact tool enters the impact mode; as shown in fig. 11 and 12, when the mode adjustment member 620 is moved to the second position, the impact switch member 610 is separated from the guide member 420, the guide member 420 is rotatable with respect to the housing 10, and the impact tool enters the non-impact mode.

In the present embodiment, the mode switching member 620 is rotatably provided with respect to the housing 10, and the impact switching member 610 is driven to move axially by rotation. In this way, the operation space of the mode switching member 620 can be reduced. In this manner, when switching between the second position and the first position, the mode switching member 620 is rotated by a certain angle to realize the position switching. Of course, the mode switching member 620 may be axially moved relative to the housing 10 to change the position thereof, thereby driving the impact switching member 610 to axially move.

As shown in fig. 7 and 8, the impact switching member 610 is provided with first fixing teeth 611, the guide member 420 is provided with second fixing teeth 421, and the mode adjusting member 620 rotates relative to the housing 10 and drives the impact switching member 610 to move along the center line axis X to engage or disengage the first fixing teeth 611 with or from the second fixing teeth 421. As shown in fig. 10, when the first fixing teeth 611 are engaged with the second fixing teeth 421, the impact switch member 610 may restrict the movement of the guide member 420, the guide member 420 is fixed with respect to the housing 10, and the impact tool enters the impact mode. As shown in fig. 12, when the first fixing teeth 611 are separated from the second fixing teeth 421, the guide member 420 is rotatable with respect to the housing 10, and the impact tool enters the non-impact mode.

Further, the first fixing teeth 611 and the second fixing teeth 421 are respectively provided as ratchet teeth having abutting surfaces, when the first fixing teeth 611 and the second fixing teeth 421 are engaged, the first abutting surfaces 6111 of the first fixing teeth 611 and the second abutting surfaces 4211 of the second fixing teeth 421 abut against each other, and the first fixing teeth 611 guide the rotation of the guide member 420 only in one direction. Thus, when the first fixing teeth 611 are coupled to the second fixing block 421, the impact switching member 610 can only restrict the one-way rotation of the guide member 420. That is, assuming that the impact switch 610 can restrict the guide 420 from rotating clockwise as viewed in fig. 7, when the impact structure shaft 434 rotates clockwise, the first guide climbs along the climbing section 4331, falls from the falling section 4332 to the lowest point of the next climbing section when moving to the highest point of the climbing section 4331, and so on, the hammer 410 can move axially; when the impact structure shaft 434 is rotated counterclockwise, the first guide member 432 cannot move from the lowest point of one climbing section 4331 to the highest point of the other climbing section 4331, the first guide member 432 is stuck at the falling section 4332, the impact switching member 610 cannot restrict the guide member 420, and the guide member 420 rotates along with the hammer 410, and the hammer 410 does not rotate relative to the guide member 420, so that the first guide member 432 is not stuck at the guide member 420, that is, the jamming of the motor in the reverse rotation can be prevented.

Further, in the present embodiment, when the first fixing teeth 611 are engaged with the second fixing teeth 421, the guide 420 and the impact switch member 610 partially overlap in the axial direction of the tool spindle 50. Specifically, as shown in fig. 7, the position of the second fixing teeth 421 on the guide member 420 is close to the center in the axial direction of the guide member 420, so that, as shown in fig. 10, when the first fixing teeth 611 are engaged with the second fixing teeth 421, the guide member 420 and the impact switch member 610 partially overlap in the axial direction of the tool spindle 50. With this configuration, the movement space required for the guide member 420 and the impact switch member 610 in the axial direction of the tool spindle 50 can be reduced, resulting in a compact structure.

Further, the guide member 420 has a guide body 426. The guide body 426 has an outer peripheral surface 4261. The first fixing teeth 611 are protruded on an outer circumferential surface 4261 of the guide body 426, and a gap is formed between the first fixing teeth 611 and an end of the outer circumferential surface 421 close to the impact switch member 610. In this way, the impact switching member 610 can move toward the guide member 420 until being engaged with the second fixing teeth 421 or separated from the second fixing teeth 421 under the support of the outer circumferential surface 4261, so as to ensure smooth and stable reciprocating movement of the guide member 420. Referring to fig. 8, the impact switch 610 is further provided with a mode coupling portion 613. Referring to fig. 13, the mode adjuster 620 is provided with a mode guide 623. Referring to fig. 3 and 4, the mode adjustment mechanism further includes an elastic member 630 abutting against the impact switch member 610, the elastic member 630 providing the impact switch member 610 with a driving force to move the guide member 420 to a position of engagement with the guide member 420, and when the mode adjustment member 620 rotates from the first position in fig. 9 to the second position in fig. 11, the mode guide portion 623 drives the mode mating portion 613 to move against the force of the elastic member 630 to separate the impact switch member 610 from the guide member 420.

The front end of the housing 10 is provided with a chuck assembly 11 for holding a tool, which may be changed according to an operating condition or an operation mode of the impact tool 100. The chuck assembly 11 is coupled to the tool spindle 50 and is rotated by the tool spindle 50.

As shown in fig. 14 and 15, the chuck assembly 11 may include a chuck body 12 connected to the tool spindle 50, a plurality of jaws 13 penetrating the chuck body 12, a lock nut 14 locked with the jaws 13, and a rotation stopping device for preventing the jaws 13 from being released in a locked position; rotation of the lock nut 14 relative to the jaws in a third direction can drive the jaws 13 to a locked position.

The chuck body 12 is provided with an axial passage for the plurality of clamping jaws 13 to penetrate through, and the front ends of the plurality of clamping jaws 13 contract or expand along the radial direction in the moving process so as to clamp or release the cutter. Specifically, the inner wall surface of the jaw 13 near the front end forms a clamping surface, which is wedge-shaped. When the clamping jaws 13 move forwards in the axial channel, the wedge-shaped clamping surfaces of the clamping jaws 13 are gradually folded inwards to form a clamping space in an enclosing manner, and the clamping spaces are tightly attached to the outer wall of the cutter, so that the cutter is fixedly clamped. Conversely, as the plurality of jaws 13 move rearwardly in the axial passageway, the wedge-shaped gripping surfaces of the plurality of jaws 13 gradually splay outwardly, releasing the tool.

The number of the clamping jaws 13 may be determined according to actual situations, and may be, for example, 3, 4 …, etc., which is not limited by the embodiment of the present invention. To allow the displacement of the jaws 13 in the axial passage, in one embodiment the outer wall of the jaws 13 is provided with an external thread, the lock nut 14 is provided with an internal thread engaging the external thread, and the lock nut 14 is screwed onto the external thread of the jaws 13. The jaws 13 are moved by operating the lock nut 14.

Of course, this is only one possible way of cooperating the lock nut 14 with the jaws 13. In other embodiments, the arrangement of the internal and external threads may be reversed, i.e., the external threads are provided on the outer wall of the lock nut 14, the internal threads are provided on the inner wall of the jaws 13, and the lock nut 14 is screwed between the jaws 13.

The lock nut 14 is disposed about the chuck body 12 and is rotatable in a circumferential direction but axially fixed. Specifically, as shown in fig. 14, the chuck body 12 is necked inward at a portion where the lock nut 14 is fitted, and a limit shoulder 1202 is formed at each of both sides of the necked portion 1201. After the locking nut 14 is sleeved on the necking part 1201, the limiting shoulders 1202 on the two sides limit the locking nut, and the freedom degree of the locking nut 14 moving along the axial direction (including the axial forward and the axial backward) is lost, so that the axial fixation is realized.

In addition, in order to avoid scraping friction of the lock nut 14 against the stop shoulder 1202 when the lock nut 14 is subjected to a rotation operation, an end face bearing 15 may be provided between the lock nut 14 and the stop shoulder 1202. Thus, the lock nut 14 and the stop shoulder 1202 replace sliding friction by rolling, which greatly reduces the rotational resistance of the lock nut 14.

Since the lock nut 14 needs to be fixed in the axial direction, the outer diameters of the two stop shoulders 1202 are necessarily larger than the inner diameter of the lock nut 14. Also, to reduce or even eliminate the axial retention effect of the lock nut 14 that could otherwise be affected by axial displacement of the stop shoulder 1202 due to impact forces, the stop shoulder 1202 should not be adapted to be an additional component that is removably coupled (e.g., threadably coupled) to the collet body 12, but rather should preferably be integrally constructed with the collet body 12. In this manner, the stop shoulder 1202 cannot be removed from the chuck body 12, thereby preventing the lock nut 14 from being pierced by the end of the chuck body 12 and eventually reaching the assembly position, the necked-down region 1201.

Therefore, in this embodiment, the lock nut 14 may adopt a split splicing structure or a haver structure, and includes two semicircular splicing portions, and the inner wall of the splicing portion is provided with an internal thread. After the two splicing parts are fastened at the necking part 1201 of the chuck body 12, the fixing sleeve 16 is sleeved on the two splicing parts for radial shrinkage fixation, so that the two splicing parts are prevented from being cracked, and the lock nut 14 is formed by assembly. In addition, by virtue of the radial contraction of the fixing sleeve 16, a large friction force exists between the inner wall of the fixing sleeve 16 and the outer peripheral wall of the lock nut 14, and thus the axial and circumferential fixing of the fixing sleeve 16 and the lock nut 14 is realized.

Since the fixing sleeve 16 needs to cross over at least one of the limiting shoulders 1202 during the process of being sleeved outside the two splicing portions, and radially contracts after the sleeving is completed, the fixing sleeve 16 should have better elastic contractibility. In practice, many feasible materials including metal materials, plastics, and polymer materials have elastic toughness. Thus, the pouch 16 can be made of any of the materials described above.

Taking the above description as an example of clamping the tool, the lock nut 14 is operated to rotate in the third direction (the screwing direction of the lock nut 14), and the plurality of jaws 13 screwed therewith are moved forward in the chuck body 12. When the wedge-shaped clamping surfaces of the clamping jaws 13 just contact the outer wall of the tool, the lock nut 14 is continuously subjected to the screwing operation until the clamping jaws 13 move forward to the preset position and cannot advance any more, and the lock nut 14 cannot continuously rotate along the screwing direction, so that the tool is tightly clamped between the clamping jaws 13 at the moment.

Based on the requirements of the impact operation, after the fastening and clamping of the tool is completed, it is desirable that the plurality of clamping jaws 13 be stably held at the current predetermined position without backlash during the operation of the impact tool 100. Since the plurality of jaws 13 are threadedly engaged with the lock nut 14, they are passively driven or restrained by the lock nut 14. Therefore, the plurality of jaws 13 are prevented from being loosened by the back-off, and the lock nut 14 is prevented from rotating in the shackle direction.

In view of the above, the embodiments of the present invention provide a rotation stopping device for achieving the above-mentioned purpose. Specifically, as shown in fig. 14 and 16, the rotation stopping device includes a rotation stopping portion 17 fixedly disposed with respect to the chuck body 12, and a stopping claw 18 non-rotatably disposed with respect to the lock nut 14, and the stopping claw 18 is coupled to the rotation stopping portion 17 to prevent the lock nut 17 from rotating in a fourth direction opposite to the third direction with respect to the jaws 13.

It should be noted that, in the embodiment of the present invention, the third direction is a rotation direction in which the lock nut 14 drives the plurality of jaws 13 to move forward to clamp the tool, i.e., a make-up direction of the lock nut 14, and is a clockwise rotation direction L1 as illustrated in fig. 17 and 18, and correspondingly, the fourth direction is a rotation direction in which the lock nut 14 drives the plurality of jaws 13 to move backward to release the tool, i.e., a break-out direction of the lock nut 14, and is a counterclockwise rotation direction L2 as illustrated in fig. 17 and 18.

The rotation stopper 17 is engaged with the stopping end 1801 of the locking pawl 18 to prevent the locking pawl 18 from rotating in the shackle direction of the lock nut 14. Since the locking pawl 18 is circumferentially fixed with the lock nut 14, the lock nut 14 is also inhibited from rotating in the shackle direction.

In one embodiment, the rotation stop portion 17 is disposed on the outer peripheral wall of the chuck body 12, and the latch 18 is disposed outside the rotation stop portion 17 and has a latch end 1801 embedded in the rotation stop portion 17. The latch 18 is substantially in the form of a circumferentially unclosed ring and therefore has two ends. One of the ends is a stop end 1801 for mating with the rotation stop 17 and the other end is a free end 1802.

In the present embodiment, the rotation stopper 17 is fixed to the chuck body 12 at least in the circumferential direction, and may be an additional component fixed to the chuck body 12, may be integrally configured with the chuck body 12, or may be a part of the structure of the chuck body 12 itself. In a possible embodiment, the rotation stop 17 can be a ratchet or a blind hole.

In the embodiment where the rotation stop portion 17 is a ratchet, the ratchet may be formed on an outer wall of a ring body, and the ring body on which the ratchet is formed may be an outer ratchet ring, which is sleeved on the chuck body 12 and fixed to the chuck body 12 in the circumferential direction. Alternatively, the ratchet teeth may be integrally formed with the cartridge body 12 and formed on the outer peripheral wall of the cartridge body 12.

As shown in fig. 19, the ratchet teeth have a root surface 1701 and a back 1702, the root surface 1701 defining together with the back 1702 of the adjacent ratchet tooth a tooth slot 1703, wherein the dotted line is the addendum circle of the ratchet tooth, the angle α between the normal direction L0 of the root surface 1701 and the threading direction L1 of the lock nut 14 is smaller than 90 °, i.e. the angle between the root surface 1701 and the tangent at the location of the tooth is smaller than 90 °, whereby, when the holding pawl 18 is inserted into the tooth slot 1703 and brought into abutment with the root surface 1701, no sliding cut occurs, leading to rotation stop failure.

Wherein the normal direction L0 of the tooth root face 1701 is a direction perpendicular to the tooth root face 1701 and directed outward of the ratchet teeth, as indicated by arrow L0 illustrated in fig. 17 to 19, and the pull-up direction L1 of the lock nut 14 is a tangential direction of the ratchet teeth at the addendum circle.

The tooth backs 1702 are inclined toward the threading direction of the lock nut 14, that is, the included angle between the face where the tooth backs 1702 are located and the threading direction of the lock nut 14 is an acute angle. In this way, the stop end 1801 can slide on the tooth back 1702, and when the sliding is stopped, it is inserted into the corresponding tooth slot 1703 and abuts against the tooth root face 1701, so as to suppress the tendency of the stop pawl 18 to rotate in the unscrewing direction of the lock nut 14, and achieve the limit.

In the embodiment where the rotation stop portion 17 is a blind hole, similar to the above, the blind hole may be formed in a ring body, and the ring body is at least circumferentially fixed on the chuck body 12. Alternatively, a blind bore may be provided in the chuck body 12, forming part of the structure of the chuck body 12 itself.

In addition, the blind hole is a plurality of, and a plurality of blind holes are located same circumference to along the even arrangement of circumference outside chuck body 12. And, a plurality of blind holes are provided toward the direction of the fastening of the lock nut 14. Specifically, an included angle between the opening direction of the blind hole and the screwing direction of the lock nut 14 may be smaller than 90 °. Thus, the stop end 1801 can slide on the circumferential surface defined by the plurality of blind holes (substantially, the outer circumferential surface of the ring body, or the outer circumferential surface of the chuck body 12), and when the sliding is stopped, the stop end is inserted into the corresponding blind hole and abuts against the bottom wall surface of the blind hole, so as to suppress the tendency of the stop claw 18 to rotate in the unscrewing direction of the lock nut 14, thereby achieving the limiting.

The rotation stop 17 has a stop surface for engagement with the stop end 1801, which stop surface is the root surface 1701 of the ratchet tooth or the bottom wall surface of the blind hole, respectively, corresponding to embodiments where the rotation stop 17 is a ratchet tooth or a blind hole. When the rotation stopper 17 is a blind hole, the blind hole may be a flat square hole having a regular axial direction or a cylindrical (for example, cylindrical) hole, and the bottom wall and the opening may be substantially parallel. Therefore, when the angle between the opening direction of the blind hole and the screwing direction of the lock nut 14 is smaller than 90 °, that is, the angle between the bottom wall of the blind hole, i.e., the normal direction of the stop surface, and the screwing direction of the lock nut 14 may be smaller than 90 °.

That is, the angle between the normal direction of the stop face and the make-up direction of the lock nut 14 is less than 90 °. However, it should be noted that the angle between the normal direction of the stop surface and the screwing direction of the lock nut 14 is not too large, otherwise the stop end 1801 is not easily inserted or inserted into the rotation stop portion 17. Therefore, it is necessary to limit the lower limit of the angle. In practice, the included angle is not greater than 20 °, and may take a value of 0 °, 3 °, 5 °, 7 °, 10 °, 12 °, 15 °, 18 °, 20 °, or the like, for example. Thus, the stopping surface can have better verticality, and the stopping end 1801 can be smoothly embedded or inserted into the rotation stopping part 17; the stopper 1801 may have a slight inclination to stop the stopper 1801, so as to prevent the stopper 1801 from slipping.

In one embodiment, the angle between the normal direction of the stop surface and the threading direction of the lock nut 14 may be 0 °, i.e. the normal direction of the stop surface is parallel to the threading direction of the lock nut 14. At this time, the stopper surface is perpendicular to the outer peripheral wall of the cartridge body 12. When the rotation stoppers 17 are ratchet teeth, the stopper surface is perpendicular to the outer peripheral wall of the cartridge body 12, that is, the tooth flank 1701 is perpendicular to the outer peripheral wall of the cartridge body 12. When the rotation stop portion 17 is a blind hole, the stop surface is perpendicular to the outer peripheral wall of the cartridge body 12, that is, the bottom wall surface of the blind hole is perpendicular to the outer peripheral wall of the cartridge body 12.

In addition, the stop surface is parallel to the axial direction of the tool spindle 50, and the impact mechanism impacts in the axial direction, which is also parallel to the axial direction of the tool spindle 50. The impact direction of the impact mechanism is thus parallel to the stop face. The direction in which the stop end 1801 of the locking pawl 18 is disengaged from the stop surface is radially outward, i.e. the direction of the impact mechanism is perpendicular to the direction in which the stop end 1801 is disengaged. The impact of the impact mechanism in the axial direction has no component force action in the radial direction perpendicular to the impact direction, so that the impact of the impact mechanism does not generate radial (including radially outward and radially inward) force on the stopping end 1801 of the stopping claw 18. Then the stop end 1801 will not be disengaged from the rotation stop 17 by the impact movement of the impact mechanism. Therefore, once the stopping end 1801 of the stopping pawl 18 is inserted or inserted into the rotation stop 17, there is no need to consider the problem of the self-loosening of the cartridge due to the impact motion during the operation of the impact tool 100, except for human handling factors.

Thus, by providing the rotation stop portion 17 on the outer peripheral wall of the cartridge body 12 and locking the locking claw 18 circumferentially fixed to the nut 14 outside the cartridge body 12, the impact of the impact mechanism is not in the same direction as the engagement of the locking claw 18 and the rotation stop portion 17. Therefore, the stop pawl 18 cannot be separated from the rotation stop part 17 due to the impact motion of the impact mechanism, and the problem that the chuck is loosened by itself in the working process of the active impact tool with large impact force is solved.

Also, the impact of the impact mechanism does not generate a force in the circumferential direction on the lock nut 14. Thus, the lock nut 14 does not have a problem of self-loosening or self-tightening during operation of the impact tool 100.

In this embodiment, the shape of the stopping end 1801 of the stopping claw 18 may also be changed according to the matching manner of the stopping claw 18 and the rotation stop portion 17, so that the stressed state of the stopping claw 18 is different.

As shown in fig. 17 and 18, in a possible embodiment, the stopping end 1801 and the rotation stopper 17 may be inserted or embedded. At this time, the stopper end 1801 is of a straight-line structure, ensuring smooth insertion or insertion into the rotation stopper 17. The shape of the stopper 1801 is adapted to the shape of the rotation stopper 17, and may be, for example, a flat shape, a rod shape, a column shape, or the like. When the stop end 1801 is inserted into the ratchet, it abuts the stop surface. At this time, the latch 18 is in a stressed state.

In another possible embodiment, the stopping end 1801 and the rotation stop portion 17 may be a hook-type engagement. Then the stop end 1801 is now in a hook-like configuration. When the stop end 1801 is inserted into the ratchet, it is hung on the stop surface, or the stop end 1801 is hooked by the stop surface. At this time, the latch 18 is in tension.

In the present embodiment, the retaining claw 18 has elasticity at least at a portion near the retaining end 1801, so that the retaining end 1801 has a tendency to spring radially outward. The spring-up direction of the stopper end 1801 is perpendicular to the impact direction of the impact mechanism. That is, the stopper end 1801 always has a tendency to move out of the rotation stopper 17. As can be seen from the above, the impact mechanism generates an impact force in the axial direction, and will not generate a component force in the radial direction. Therefore, once the stopping end 1801 is pressed by an external force and embedded into the rotation stop portion 17, the impact force is eliminated, and the impact mechanism impacts in the axial direction during operation, so that the stopping end 1801 is not affected and the stopping end 1801 is separated from the rotation stop portion 17.

Therefore, to insert or insert the stopping end 1801 into the rotation stop portion 17, a pressing member is provided outside the stopping claw 18 to press the stopping end 1801 radially inward against the radially outward elastic force of the stopping end 1801.

As shown in fig. 13 to 15, 17 and 18, the pressing member is a cylindrical outer sleeve 19 which is fitted over the chuck body 12 and receives the locking pawl 18 and the lock nut 14 therein. Also, since the latch claw 18 has elasticity to spring the latch end 1801 radially outward, the latch end 1801 always abuts against the inner wall of the outer sleeve 19. Accordingly, the inner wall of the outer sleeve 19 applies a counter-urging force to the stop end 1801. The outer diameter of the lock nut 14 is smaller than the inner diameter of the outer sleeve 19 so that there is a gap between the lock nut 14 and the outer sleeve 19.

The outer sleeve 19 is axially fixed, as shown in fig. 13 and 15, a specific axial fixing manner may be that the outer wall of the chuck body 12 is recessed inward to form a peripheral limiting groove, one end (front end) of the outer sleeve 19 is bent or extended inward in the radial direction to form a limiting portion, and the limiting portion is inserted into the peripheral limiting groove to achieve axial limiting. In addition, an end cap 20 is detachably provided at one end (rear end) of the cartridge body 12 close to the housing 10, and the end cap 20 is accommodated in the outer sleeve 19 and supports the outer sleeve 19 so that the outer sleeve 19 maintains a good profile. At the same time, the end of the jacket 19 can be plugged.

The outer casing 19 may be a double-layered structure including a protective sleeve 1901 and an inner shell 1902 laminated within the protective sleeve 1901. The protective sleeve 1901 and the inner housing 1902 are secured together without relative axial or circumferential movement therebetween.

The protective sleeve 1901 has better wear resistance, and may be made of a material with better wear resistance, such as, but not limited to, a metal material or an alloy material containing manganese and chromium. Alternatively, the protective sleeve 1901 may be formed entirely of any feasible material and have an outer surface provided with a wear-resistant coating. Alternatively, the protective sleeve 1901 is integrally made of a metal material subjected to the quenching process. In addition, the surface of protective sheath 1901 is equipped with anti-skidding line to the frictional force when the increase staff grips prevents to skid.

The inner wall of the inner housing 1902 has lubricity to reduce frictional resistance between it and the dog 18, and may be made of a material having certain lubricity, for example, as referred to as a material of a self-lubricating bushing or a copper-based bushing. Alternatively, the inner wall of the inner shell 1902 is coated with a solid lubricating material.

As shown in fig. 17 and 18, the inner wall of the outer housing 19 (specifically, the inner wall of the inner housing 1902) is recessed to form a release groove 1903, and the latch 18 is bulged radially outward at a position near the latch end 1801 to form a contact protrusion 1803. The relief recess 1903 serves to provide space for the radially outward springing of the contact protrusion 1803 to disengage the stop end 1801 adjacent the contact protrusion 1803 from the rotation stop 17.

Both ends of the release groove 1903 in the circumferential direction smoothly transit the inner wall of the outer sleeve 19, and both ends of the contact protrusion 1803 in the circumferential direction also smoothly transit the locking claws 18. The smooth transition may be a circular arc transition. By the smooth transition structure design of the two ends of the release groove 1903 and the contact protrusion 1803 along the circumferential direction, not only can the frictional resistance when the contact protrusion 1803 slides into or out of the release groove 1903 be reduced, but also the wear of the contact protrusion 1803 can be reduced.

Further, the length of the release groove 1903 in the circumferential direction is larger than the length of the contact protrusion 1803 in the circumferential direction. Thus, when unlocking, the contact protrusion 1803 can be ensured to completely slide into the release groove 1903, and the situation that the locking end 1801 cannot be bounced and further unlocking failure is caused due to the fact that the contact protrusion 1803 cannot fully enter the release groove 1903 is avoided.

It should be noted that the length of the release groove 1903 in the circumferential direction is not much greater than the length of the contact protrusion 1803 in the circumferential direction, otherwise, the outer sleeve 19 has a degree of freedom to rotate greatly after the contact protrusion 1803 completely slides into the release groove 1903 to complete the unlocking. Therefore, the outer sleeve 19 has a large degree of freedom in circumferential grid movement, which may cause the contact protrusion 1803 to slide and rub in the release groove 1903 in a reciprocating manner, and the contact protrusion 1803 may collide with the side wall of the release groove 1903, resulting in abrasion of the end surface of the contact protrusion 1803 and the side wall of the release groove 1903.

Therefore, in practice, the length of the release groove 1903 in the circumferential direction is slightly greater than the length of the contact protrusion 1803 in the circumferential direction, for example, the length of the release groove 1903 in the circumferential direction is greater than 10% -30% of the length of the contact protrusion 1803 in the circumferential direction, that is, the length of the release groove 1903 in the circumferential direction is 1.1-1.3 times of the length of the contact protrusion 1803 in the circumferential direction.

Because the dogs 18 are circumferentially fixed outside the chuck body 12, the outer sleeve 19 is rotatable around the chuck body 12. Therefore, in order to prevent the outer sleeve 19 from rotating and causing the contact protrusion 1803 to be fitted into the release groove 1903 when the locking pawl 18 is fitted into the rotation stop portion 17, thereby causing unlocking, it is necessary to circumferentially limit or stop the rotation of the outer sleeve 19 when the locking pawl 18 is fitted into the rotation stop portion 17.

Specifically, as shown in fig. 18, the inner wall of the outer sleeve 19 is formed with a first stopper groove 1904 in a recessed manner, and the locking pawl 18 is formed with a stopper projection 1804 bulging outward in the radial direction. When the release recess 1903 is misaligned with the contact protrusion 1803, the limit protrusion 1804 is fitted into the first limit recess 1904. That is, when the rotation stopper 17 is engaged with the stopper end 1801 and the cartridge assembly 11 is in the clamped state, the limit projection 1804 is engaged with the first limit recess 1904.

In this embodiment, the limit projection 1804 is provided at a position near the free end 1802 of the latch 18, and the elasticity of the latch 18 also causes the limit projection 1804 to have a tendency to spring radially outward, so that the limit projection 1804 is always pressed against the inner wall of the sheath 19.

The contact protrusion 1803 is circumferentially offset from the limit protrusion 1804 by approximately 180 °, where "approximately" may be understood as approaching or within a predetermined range from a target value. For example, the phase difference between the contact protrusion 1803 and the limit protrusion 1804 in the circumferential direction is between [0 °, 20 ° ] and 180 °. Thus, the contact protrusion 1803 is located generally on the opposite side from the limit protrusion 1804. Therefore, when the moving end is inserted into the rotation stop portion 17, the contact protrusion 1803 and the limit protrusion 1804, which are substantially located at opposite sides, push against the inner wall of the outer sleeve 19 by means of elastic force, and perform a balanced rotation stop function on the outer sleeve 19 by means of the friction force generated by the pushing pressure.

By means of the cooperation of the first limiting groove 1904 and the limiting protrusion 1804 and the contact friction between the contact protrusion 1803, the limiting protrusion 1804 and the inner wall of the jacket 19, the circumferential limiting or rotation stopping effect of the jacket 19 can be better achieved. Therefore, the impact tool 100 can be prevented from being unlocked halfway due to the rotation of the outer sleeve 19 during operation.

As shown in fig. 17, the engagement of the release recess 1903 and the contact protrusion 1803 can limit the position of the outer sleeve 19 when the locking mechanism is in the unlocked state. However, the position limiting effect of the outer sleeve 19 is still to be improved by only one-point engagement of the release groove 1903 and the contact protrusion 1803.

In view of this, the inner wall of the outer sleeve 19 is concavely formed with a second stopper groove 1905. As shown in fig. 17, the limit projection 1804 is fitted into the second limit recess 1905 when the contact projection 1803 is fitted into the release recess 1903. Therefore, the limiting protrusion 1804 is embedded into the second limiting groove 1905, the contact protrusion 1803 is embedded into the release groove 1903, double-point matching is formed, contact friction among the contact protrusion 1803, the limiting protrusion 1804 and the inner wall of the outer sleeve 19 is assisted, and circumferential limiting effect of the outer sleeve 19 when the locking mechanism is in an unlocking state is improved.

In addition, since the phase difference between the contact protrusion 1803 and the limit protrusion 1804 in the circumferential direction is substantially 180 °, when the contact protrusion 1803 is fitted into the release groove 1903, the limit protrusion 1804 is fitted into the second limit groove 1905. The phase difference between the release groove 1903 and the second limit groove 1905 in the circumferential direction is also substantially 180 °. Thus, the fitting of the limit projection 1804 into the second limit recess 1905 and the fitting of the contact projection 1803 into the release recess 1903 form a double-dot fitting, which are arranged on opposite sides of the circumference. Therefore, the limiting protrusion 1804 is embedded into the second limiting groove 1905 and the contact protrusion 1803 is embedded into the release groove 1903, so that the outer sleeve 19 can be limited in a circumferential balanced manner, and the limiting effect is better.

As described above, in order to ensure that the limiting protrusion 1804 can completely slide into the first limiting groove 1904 or the second limiting groove 1905, and avoid the problem that the circumferential limiting effect of the outer sleeve 19 is weakened because the limiting protrusion 1804 cannot sufficiently enter the corresponding limiting groove, the circumferential lengths of the first limiting groove 1904 and the second limiting groove 1905 are all greater than the circumferential length of the limiting protrusion 1804. In addition, the length of the first limit groove 1904 or the second limit groove 1905 in the circumferential direction may be slightly greater than the length of the limit protrusion 1804. For the similarity, refer to the above description, which is not repeated herein.

Similarly, both ends of the limiting protrusion 1804 in the circumferential direction smoothly transition with the locking claws 18, and since the movement range of the limiting protrusion 1804 is the first limiting recess 1904 and the second limiting recess 1905 and the inner wall portion of the outer sleeve 19 between the two limiting recesses, the ends of the first limiting recess 1904 and the second limiting recess 1905 facing each other smoothly transition with the inner wall of the outer sleeve 19, while the ends away from each other may not smoothly transition with the inner wall of the outer sleeve 19. Even more, in order to achieve the function of the stopper limit projection 1804, it is preferable that the first limit recess 1904 and the second limit recess 1905 are as flat as possible away from the corresponding ends.

As described above, the smooth transition may be a circular arc transition. Through the structural design that the two ends of the limiting protrusion 1804, the first limiting groove 1904 and the second limiting groove 1905 face the end portions of the opposite sides in smooth transition, the frictional resistance when the limiting protrusion 1804 slides in or slides out of the limiting grooves can be reduced, and the abrasion of the limiting protrusion 1804 can be reduced.

Further, on the basis of having two spacing grooves and having elastic spacing protrusion 1804, with the help of the location feel that produces when two spacing grooves 1904, 1905 and spacing protrusion 1804 cooperate, make the operator perception overcoat 19 rotate to the position, whether spacing protrusion 1804 imbeds in corresponding spacing groove promptly.

Specifically, the inner wall of the sleeve 19 between the two retaining grooves and the inner walls of the two retaining grooves 1904, 1905 form a contoured surface against which the retaining projection 1804 exerts a radially outward spring force as it slides. When the outer sleeve 19 is held by an operator to rotate, the limiting protrusions 1804 slide on the profile surface, and the limiting protrusions 1804 can correspondingly move radially in a telescopic manner along with the undulation of the profile surface. The radial telescopic movement of the limit projection 1804 is reacted with the outer sleeve 19 by the elastic restoring force of the limit projection, so that the positioning hand feeling is generated for the operator. Further, the operator can determine whether the outer cover 19 is rotated to the position by sensing the positioning hand.

As described above, the clamping or opening of the chuck assembly 11 needs to be achieved by the axial movement of the plurality of jaws 13 driven by the rotation of the lock nut 14. Since there is a gap between the lock nut 14 and the outer sleeve 19, the rotation of the lock nut 14 is carried by the locking pawl 18 fixed to the lock nut in the circumferential direction. Thus, when the outer sleeve 19 rotates the locking pawl 18, the locking nut 14 fixed to the locking pawl 18 circumferentially performs a make-up or break-out rotation.

The locking nut 14 is sleeved with a fixing sleeve 16. Thus, the circumferential fixing of the locking pawl 18 to the union nut 14 can be achieved by the circumferential attachment of the locking pawl 18 to the fixing sleeve 16. As shown in fig. 14, 17 and 18, the locking pawl 18 is circumferentially fixed to the fixing sleeve 16 in such a manner that two limiting holes 1601 are formed in the fixing sleeve 16, the contact protrusion 1803 is inserted into the contact protrusion 1803 and inserted into one of the limiting holes 1601, and the limiting protrusion 1804 is inserted into the other limiting hole 1601. In this embodiment, the front end of the fixing sleeve 16 is formed with an extension 1602 with a reduced side wall, and the limiting hole 1601 can be opened on the extension 1602.

Since the latch 18 has elasticity such that the contact protrusion 1803 and the limit protrusion 1804 have a tendency to expand radially outward, the contact protrusion 1803 and the limit protrusion 1804 can be stably caught in the limit hole 1601 without intervention of an external force.

The working principle of the chuck assembly 11 of the impact tool 100 according to the embodiment of the present invention is described below:

in the state diagram illustrated in fig. 17, the contact protrusion 1803 is fitted into the release recess 1903, the stopper end 1801 is not fitted into the rotation stopper 17, and the cartridge assembly 11 is now in the open state. The distance between the plurality of clamping jaws 13 is larger than the outer diameter of the insertion end of the cutter, so that the cutter is inserted between the plurality of clamping jaws 13 at the beginning, and the plurality of clamping jaws 13 do not generate radial contraction acting force on the cutter. Subsequently, the outer sleeve 19 is manually operated to rotate clockwise as shown in fig. 17, specifically, the protective sleeve 1901 with anti-slip threads is rotated clockwise, through the matching limiting action between the contact protrusion 1803 and the release groove 1903 and between the limiting protrusion 1804 and the first limiting groove 1904, the outer sleeve 19 drives the locking pawl 18 to rotate clockwise together, and then the locking pawl 18 drives the locking nut 14 fixedly connected with the fixing sleeve 16 in the circumferential direction to rotate in the screwing-up direction.

When the lock nut 14 is operated to continue rotating in the threading direction until the plurality of jaws 13 contact the outer wall of the insertion end of the tool, the rotational resistance of the lock nut 14 begins to increase. Further, as the pull-up stroke of the lock nut 14 increases, the rotation resistance of the lock nut 14 increases more significantly. The stopping pawl 18 can continue to rotate the lock nut 14 in the make-up direction until the rotational resistance of the lock nut 14 increases to equal the sum of the frictional forces between the contact protrusion 1803 and the release recess 1903 and between the limit protrusion 1804 and the first limit recess 1904.

Once the rotational resistance of the lock nut 14 increases to exceed the critical point of the sum of the frictional forces between the contact protrusion 1803 and the release recess 1903 and between the limit protrusion 1804 and the first limit recess 1904, the lock nut 14 cannot be rotated in the make-up direction. At this time, the plurality of jaws 13 have reached the clamping dead center, and the chuck assembly 11 completes the tool clamping.

Since the lock nut 14 is stopped, the locking pawl 18 fixed to the lock nut in the circumferential direction is also stopped. At this time, continuing to rotate the outer sleeve 19 clockwise, since the latch 18 has been arrested by the lock nut 14 circumferentially fixed thereto, the contact protrusion 1803 of the latch 18 slides out of the release recess 1903 of the outer sleeve 19, and the limit protrusion 1804 correspondingly slides out of the second limit recess 1905 and toward the first limit recess 1904. At the same time, the contact protrusion 1803 of the latch 18 is pressed by the inner wall of the outer sleeve 19, is radially pressed downward, and slides on the cartridge body 12 corresponding to the outer peripheral wall of the rotation stop portion 17. Until the limit protrusion 1804 slides into the first limit groove 1904, the rotation of the outer sleeve 19 is stopped, and the stop end 1801 of the stop pawl 18 is inserted into the rotation stop portion 17, thereby completing the locking.

The above is the flow of the clamping operation of the chuck assembly 11, and the flow of the opening operation of the chuck assembly 11 is the reverse of the above, specifically as follows:

in the state diagram as illustrated in fig. 18, the stopper end 1801 is fitted into the rotation stopper 17, and the cartridge assembly 11 is now in the clamped state. When it is desired to remove the tool, the outer sleeve 19 is manually operated to rotate counterclockwise as illustrated in fig. 18, and the holding pawl 18 has a tendency to rotate counterclockwise together with the outer sleeve 19 due to contact friction between the inner wall of the outer sleeve 19 and the contact protrusion 1803. However, since the stopper end 1801 is fitted into the rotation stopper 17 and the counterclockwise rotation tendency of the locking pawl 18 is suppressed, the locking pawl 18 remains relatively stationary, and the lock nut 14 fixed to the locking pawl 18 in the circumferential direction is also relatively stationary and does not rotate in the shackle direction. Thereby, the contact protrusion 1803 can slide on the inner wall surface of the outer cover 19.

Until the outer sleeve 19 rotates until the release recess 1903 corresponds to the contact protrusion 1803, the contact protrusion 1803 is inserted into the release recess 1903 under the action of the radially outward elastic force, and the limit protrusion 1804 slides into the second limit recess 1905 from the first limit recess 1904, at which time the positional relationship between the contact protrusion 1803 and the release recess 1903, and between the limit protrusion 1804 and the second limit recess 1905, are as shown in fig. 17. At the same time, the stopping end 1801 is driven to bounce outwards, and is separated from the rotation stopping portion 17, so that unlocking is completed.

Subsequently, the outer sleeve 19 continues to rotate counterclockwise, under the action of the cooperation between the contact protrusion 1803 and the release recess 1903 and the limit protrusion 1804 and the second limit recess 1905, the locking pawl 18 is driven to rotate clockwise, the lock nut 14 fixed to the locking pawl 18 circumferentially also rotates clockwise, that is, the lock nut 14 rotates in the tripping direction, the chuck assembly 11 is opened, and the tool removal is completed.

It should be noted that, since the locking pawl 18 is rotated by the outer sleeve 19 by means of the friction force between the contact protrusion 1803 and the release recess 1903 and between the limit protrusion 1804 and the first limit recess 1904, the magnitude of the friction force is positively correlated to the contact pressure between the contact protrusion 1803 and the release recess 1903 and between the limit protrusion 1804 and the first limit recess 1904.

Therefore, the operator can hold the outer sleeve 19 at the portions of the outer sleeve 19 corresponding to the release recess 1903 and the first stopper recess 1904 during the rotation of the outer sleeve 19. Therefore, the contact pressure between the contact protrusion 1803 and the release groove 1903 and the contact pressure between the limit protrusion 1804 and the first limit groove 1904 can be increased, so as to improve the total friction force between the outer sleeves 19 of the locking claws 18, and prevent the locking claws 18 from being restrained by the locking nut 14 due to the fact that the friction force is too small and the rotation resistance of the locking nut 14 cannot be overcome, so that the locking nut 14 stops rotating too early, the clamping force of a plurality of chucks is small, and the cutter cannot be clamped.

The above description is only for the embodiments of the present invention, and those skilled in the art can make various changes or modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention according to the disclosure of the application document.

Claims (10)

1. An impact tool, comprising:

a housing;

a motor housed in the housing;

a tool spindle rotationally driven by a motor and having a central axis;

the impact mechanism is positioned between the motor and the tool spindle and is used for transmitting impact on the tool spindle in the axial direction of the tool spindle; the method comprises the following steps: the energy storage device comprises a ram, a guide piece, a first guide piece arranged on the ram, a second guide piece arranged on the guide piece and an energy storage element abutted against the ram; when the hammer rotates relative to the guide piece, the first guide piece and the second guide piece are matched to drive the hammer to move along the central axis in a first direction against the acting force of the energy storage element, and the energy storage element can drive the hammer to move along the central axis in a second direction opposite to the first direction so as to impact the tool spindle;

a transmission mechanism for transmitting power of the motor to at least one of the hammer and the guide;

the chuck component is provided with a chuck body connected with the tool spindle, a plurality of clamping jaws arranged in the chuck body in a penetrating way, a locking nut locked with the clamping jaws and a rotation stopping device for preventing the clamping jaws from loosening at a locking position; the locking nut can drive the clamping jaw to move to a locking position by rotating along a third direction relative to the clamping jaw, the rotation stopping device comprises a rotation stopping part fixedly arranged relative to the chuck body and a stopping jaw arranged in a non-relative-rotation mode with the locking nut, and the stopping jaw is matched and connected with the rotation stopping part to prevent the locking nut from rotating along a fourth direction opposite to the third direction relative to the clamping jaw.

2. The impact tool of claim 1, wherein said impact tool has at least two modes of operation, an impact mode and a non-impact mode; in the impact mode, the hammer rotates relative to the guide piece; in the non-impact mode, the hammer and the guide piece do not rotate relatively;

the impact tool further comprises a mode adjustment mechanism for switching between an impact mode and a non-impact mode, the mode adjustment mechanism being operable to switch between a first state and a second state; in a first state, the hammer can rotate relative to the guide piece, and the impact tool is in an impact mode; in a second state, the guide member is capable of being rotated by the motor and the impact tool is in a non-impact mode.

3. The impact tool of claim 1, wherein the rotation stop portion is provided on an outer peripheral wall of the cartridge body, and the locking claw is fitted over the rotation stop portion and has a locking end fitted into the rotation stop portion.

4. A percussion tool as claimed in claim 3, wherein the rotation stop has a stop face for engagement with the stop end, the angle between the normal to the stop face and the third direction being less than 90 °.

5. Impact tool according to claim 4, characterised in that the stop surface is parallel to the impact direction of the impact mechanism; the stop end is pressed against the stop surface when being embedded into the rotation stop part; or the stopping end is hook-shaped, and the stopping end is hooked with the stopping surface when being embedded into the rotation stopping part.

6. The impact tool of claim 1, wherein the rotation stop is a ratchet or a blind hole, and the blind hole is inclined toward the third direction.

7. A percussion tool as claimed in claim 3, in which the holding pawl has resilience which gives the holding end a tendency to spring radially outwardly; the bounce direction of the stop end is perpendicular to the impact direction of the impact mechanism.

8. The impact tool of claim 7, wherein the chuck body is provided with a circumferentially rotatable outer sleeve, the dogs being disposed within the outer sleeve; a release groove is formed on the inner wall of the outer sleeve in a concave mode, and a contact bulge is formed outwards in the radial direction at the position, close to the stopping end, of the stopping claw; when the outer sleeve rotates to the position that the release groove corresponds to the contact protrusion, the contact protrusion is embedded into the release groove, and the stop end bounces to be separated from the rotation stop part.

9. The impact tool of claim 8, wherein when the outer sleeve is rotated to a position where the release groove is misaligned with the contact protrusion, the contact protrusion contacts the inner wall of the outer sleeve, and the stopper end is pressed down to be fitted into the rotation stopper portion; the length of the release groove in the circumferential direction is greater than the length of the contact protrusion in the circumferential direction; the two ends of the release groove along the circumferential direction are in smooth transition with the inner wall of the outer sleeve, and the two ends of the contact protrusion along the circumferential direction are in smooth transition with the locking claws.

10. The impact tool of claim 8, wherein the inner wall of the outer sleeve is concavely formed with a first limit recess, and the stopping claw is formed with a radially outward limit projection; when the release groove is staggered with the contact protrusion, the limit protrusion is embedded into the first limit groove.

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