CN112109045A

CN112109045A - Multifunctional electric hammer

Info

Publication number: CN112109045A
Application number: CN202010242417.4A
Authority: CN
Inventors: 刘爱国
Original assignee: Jiangsu Dongcheng Tools Technology Co Ltd
Current assignee: Jiangsu Dongcheng Tools Technology Co Ltd
Priority date: 2020-03-31
Filing date: 2020-03-31
Publication date: 2020-12-22

Abstract

A multifunctional electric hammer comprises a shell, a motor, a transmission mechanism, a cylinder and a rotary switching mechanism, wherein the transmission mechanism is driven by the motor and comprises an output gear. The rotary switching mechanism comprises an inner gear ring fixed on the shell, a return spring and a sleeve assembly which are sleeved on the cylinder, and a switching part, wherein two ends of the return spring are respectively abutted against the cylinder and the sleeve assembly. The sleeve assembly comprises a sliding sleeve, a check ring, an outer gear ring and a compression spring, wherein the check ring, the outer gear ring and the compression spring are sleeved on the sliding sleeve, the check ring is fixed on the sliding sleeve, two ends of the compression spring are respectively abutted against the outer gear ring and the sliding sleeve to push the outer gear ring, the sleeve assembly is integrated, and the sliding sleeve is provided with an input gear located at the rear section. When the sleeve assembly is positioned at the right end, the input gear is meshed with the output gear so that the sleeve assembly drives the cylinder to rotate together, and when the sleeve assembly is positioned at the left end, the outer gear ring is meshed with the inner gear ring so that the cylinder is fixed relative to the machine shell. The sleeve component is an integral component, has compact structure and can be assembled in advance, and is beneficial to assembly operation and subsequent maintenance.

Description

Multifunctional electric hammer

[ technical field ]

The invention relates to the field of electric tools, in particular to a multifunctional electric hammer used in the field of hammer drills.

[ background art ]

With the rapid development of social economy, the electric hammer is widely applied to workplaces such as construction industry, decoration industry, social service industry, industrial and mining enterprises and the like, and meanwhile, a function switching device is usually arranged on the electric hammer in order to conveniently realize the switching of functions such as hammer blocking, hammer drill blocking, neutral blocking and the like of the electric hammer. Please refer to chinese utility model patent publication No. CN202964584U, which discloses an electric hammer, comprising a housing, a positioning sleeve, a cylinder sleeve tooth, a clutch and a toggle button, wherein the outer ring of the positioning sleeve is engaged with the inner wall of the housing, the cylinder sleeve tooth is in clearance fit with the cylinder and engaged with a transmission mechanism, the clutch is in axial movement fit with the cylinder through a flat key, and the toggle button is toggled through an eccentric pin of the toggle button, so as to change the position of the clutch on the cylinder, thereby realizing the function switching of the electric hammer. When the eccentric pin of the shifting knob is at the leftmost end, the clutch is meshed with the positioning sleeve and separated from the cylinder sleeve teeth, and the cylinder is fixed at the moment, so that the pick angle at the front part of the electric hammer is locked. When the eccentric pin of the toggle button is at the rightmost end, the clutch is meshed with the cylinder sleeve teeth and separated from the positioning sleeve under the action of the reset spring, and the cylinder of the electric hammer can rotate at the moment. When the eccentric pin of the shifting button is in the middle, the clutch, the cylinder sleeve gear and the positioning sleeve are separated, and the rotation angle of the pickaxe can be manually adjusted. However, the structure of each part in the function switching device of the electric hammer is relatively scattered, so that the parts are troublesome to assemble when the electric hammer is assembled, and the parts are difficult to disassemble and assemble when the electric hammer is repaired.

Accordingly, there is a need for an improved multi-functional electric hammer that overcomes the drawbacks of the prior art.

[ summary of the invention ]

In view of the defects of the prior art, the invention aims to provide a multifunctional electric hammer which is compact in structure and convenient to assemble.

The technical scheme adopted by the invention for solving the problems in the prior art is as follows: a multifunctional electric hammer comprises a shell, a motor, a transmission mechanism, a cylinder and a rotary switching mechanism. The motor set up in just export the revolving force in the casing, drive mechanism by motor drive just includes the output shaft and is located output gear on the output shaft, the cylinder supports in the casing, rotary switching mechanism is located including being fixed in the ring gear of casing inner wall, cover reset spring and the sleeve subassembly in the cylinder periphery and assemble in switching part on the casing, reset spring is located sleeve subassembly's the place ahead, just reset spring's one end connect in the cylinder, other end butt in sleeve subassembly, sleeve subassembly for the cylinder is along the axial side-to-side slip. The sleeve assembly comprises a sliding sleeve, a check ring, an outer gear ring and a compression spring, wherein the check ring, the outer gear ring and the compression spring are sleeved on the periphery of the front section of the sliding sleeve, the check ring is fixed on the sliding sleeve, one end of the compression spring is abutted against the outer gear ring, and the other end of the compression spring is connected to the sliding sleeve so as to push the outer gear ring to be abutted against the check ring, so that the sleeve assembly forms a whole. The sliding sleeve is provided with a pushing part positioned at the middle section and an input gear positioned at the rear section, and the pushing part is used for being pushed by the switching part to drive the sleeve component to move along the axial direction; when the switching part drives the sleeve assembly to be positioned at the right end, the input gear is meshed with the output gear of the transmission mechanism so that the sleeve assembly drives the cylinder to rotate together, and when the switching part drives the sleeve assembly to be positioned at the left end, the outer gear ring of the sleeve assembly is meshed with the inner gear ring so that the cylinder is fixed relative to the shell.

The further improvement scheme is as follows: the sliding sleeve is connected to the outer wall of the cylinder by a pin, and the outer ring gear is connected to the front end of the sliding sleeve by a pin and slides axially relative to the sliding sleeve.

The further improvement scheme is as follows: the sliding sleeve is provided with an annular groove which is inwards sunken from the peripheral surface of the front end, the retainer ring is partially contained in the groove to be fixed on the sliding sleeve, and the compression spring is positioned between the rear end face of the outer gear ring and the front end face of the abutting portion to abut against and push the outer gear ring to abut against the retainer ring.

The further improvement scheme is as follows: the cylinder is provided with an annular bulge part which protrudes outwards from the peripheral surface of the front end, and the front end of the return spring abuts against the rear end face of the bulge part; the sliding sleeve is provided with a first inner wall face located at the front end, a second inner wall face located at the rear end and a step face connecting the first inner wall face and the second inner wall face, the first inner wall face of the sliding sleeve is far away from the cylinder compared with the second inner wall face, a gap is formed between the first inner wall face and the outer peripheral surface of the cylinder, and at least part of the rear end of the reset spring is contained in the gap and is abutted against the step face.

The further improvement scheme is as follows: the output gear is a small bevel gear, the input gear is a large bevel gear, and a bevel gear transmission mechanism is formed when the input gear is meshed with the output gear.

The further improvement scheme is as follows: the switching component is provided with an eccentric pin which protrudes into the shell and abuts against the rear end face of the abutting part, the eccentric pin abuts against the abutting part to drive the sliding sleeve to move axially, and the sliding sleeve is switched between a state that the input gear is meshed with the output gear and the outer gear ring is separated from the inner gear ring and a state that the input gear is separated from the input gear and the outer gear ring is meshed with the inner gear ring.

The further improvement scheme is as follows: the sliding sleeve is switched by the switching part, the eccentric pin of the switching part is provided with a first position located at the rightmost end in the axial direction and a second position located at the leftmost end in the axial direction, when the eccentric pin is located at the first position, the input gear is meshed with the output gear, the outer gear ring is separated from the inner gear ring, and at the moment, the air cylinder is driven to rotate by the motor; when the eccentric pin is located at the second position, the input gear is separated from the output gear, the outer gear ring is meshed with the inner gear ring, and at the moment, the cylinder is fixed relative to the machine shell and cannot rotate.

The further improvement scheme is as follows: when the eccentric pin moves from the first position to the second position, the input gear is separated from the output gear and the return spring is compressed until the outer gear ring is meshed with the inner gear ring; when the eccentric pin moves from the second position to the first position, the outer gear ring is separated from the inner gear ring, and the return spring pushes the sliding sleeve until the input gear is meshed with the output gear.

The further improvement scheme is as follows: the eccentric pin is also provided with a middle position between the axial rightmost end and the axial leftmost end, and when the eccentric pin is positioned at the middle position, the input gear is separated from the input and output gear, and the outer gear ring is separated from the inner gear ring.

The further improvement scheme is as follows: the inner gear ring is positioned in front of the outer gear ring, and the inner gear ring is integrally formed on the inner wall of the casing or assembled and fixed on the inner wall of the casing.

Compared with the prior art, the invention has the following beneficial effects: the sleeve assembly comprises a sliding sleeve, a check ring, an outer gear ring and a compression spring, wherein the check ring, the outer gear ring and the compression spring are sequentially sleeved on the periphery of the front section of the sliding sleeve; the sleeve component is an integral component, has compact structure, can be assembled in advance before use, and is more beneficial to assembly line operation and subsequent maintenance.

[ description of the drawings ]

The following detailed description of embodiments of the invention is provided in conjunction with the appended drawings:

FIG. 1 is a top view of an electric hammer in accordance with a preferred embodiment of the present invention;

FIG. 2 is a cross-sectional view of the electric hammer shown in FIG. 1 with the eccentric pin in a first position;

FIG. 3 is a perspective view of a sleeve assembly of the electric hammer shown in FIG. 2;

FIG. 4 is an exploded schematic view of the sleeve assembly shown in FIG. 3;

FIG. 5 is a cross-sectional view of the eccentric pin of the hammer shown in FIG. 2 in an intermediate position;

fig. 6 is a cross-sectional view of the eccentric pin in a second position in the electric hammer shown in fig. 2.

The meaning of the reference symbols in the figures:

100. the multifunctional electric hammer 10, the machine shell 11, the inner gear ring 20, the cylinder 21, the bearing 22, the piston 23, the impact piece 24, the middle part 25, the piston pin 26, the return spring 27, the boss 30, the motor 31, the motor shaft 40, the crankshaft 41, the middle gear 42, the crank pin 43, the connecting rod 50, the output shaft 51, the large gear 52, the output gear 60, the sliding sleeve 61, the outer gear ring 60, the pushing part 63, the input gear 64, the retainer ring 65, the compression spring 66, the gap 67, the pin key, 68, the groove 70, the switching part 71, the toggle button 72, the eccentric pin

[ detailed description of the invention ]

Referring to fig. 1 to 4, a multifunctional electric hammer 100 according to the present invention is shown, which has at least two functions of a hammer and a hammer drill. The multifunctional electric hammer 100 includes a casing 10, and a cylinder 20, a motor 30, a transmission mechanism and a rotation switching mechanism disposed in the casing 10, wherein the motor 30 is used for outputting a rotation force and driving the cylinder 20 to actuate through the transmission mechanism. The transmission mechanism is driven by the motor 30 and comprises an impact force output mechanism and a rotating force output mechanism, the rotating force output mechanism converts the rotating force of the motor 30 into an impact force to be output to the cylinder 20, and the rotating force output mechanism outputs the rotating force of the motor 30 to the cylinder 20. The front end of the multi-functional electric hammer 100 is mounted with an operating tool (not shown) for receiving an impact force, a rotational force, or both to perform a desired operation.

Referring to fig. 2 to 4, the cylinder 20 is axially disposed in the housing 10 and rotatably supported at two shaft ends by two bearings 21. A piston 22, an impact piece 23 and an intermediate part 24 are arranged in the cylinder 20, and the piston 22 and the impact piece 23 are slidably matched in the cylinder 20. An operating tool detachably mounted on the front end of the cylinder 20, the operating tool cooperating with the intermediate member 24 of the cylinder 20 to be slidable in the axial direction of the cylinder 20 but not rotatable circumferentially relative to the cylinder 20; i.e. the operating means can rotate together with the cylinder 20. An air chamber is formed between the piston 22 and the striking element 23, and when the piston 22 moves forward, air in the air chamber is pressed and pushes the striking element 23 forward to strike the intermediate member 24, thereby causing the operating tool to perform a striking operation.

The motor 30 serves as a driving source of the multi-function electric hammer 100, and the motor 30 is provided with a motor shaft 31 vertically arranged perpendicular to the axial direction and a pinion gear at the top end of the motor shaft 31, the pinion gear being integrally formed at the top end of the motor shaft 31. The transmission mechanism comprises a crank shaft 40 and an output shaft 50 which are vertically arranged and rotatably supported in the machine shell 10, a large gear 51 of the output shaft 50 and a small gear of the motor shaft 31 are both meshed with the middle gear 41 of the crank shaft 40, and the large gear 51 of the output shaft 50 is positioned above the small gear of the motor shaft 31. A crank pin 42 is integrally formed at a top end of the crank shaft 40, and the crank pin 42 is vertically erected at a position eccentric from a rotation center of the crank shaft 40. The piston 20 is connected to a crank pin 42 of the crank shaft 40 through a connecting rod 43, and one end of the connecting rod 43 is connected to the piston 22 through a piston pin 25, thereby driving the piston 22 to reciprocate in the axial direction. The output shaft 50 is provided with an output gear 52 integrally formed at the top end and having a smaller diameter.

The rotary switching mechanism includes an annular gear 11 fixed on an inner wall of the casing 10, a return spring 26 and a sleeve assembly sleeved on an outer periphery of the cylinder 20, the sleeve assembly sliding left and right in an axial direction relative to the cylinder 20 and including a sliding sleeve 60, and a switching member 70 assembled on the casing 10. The inner gear ring 11 is positioned in front of the outer gear ring 61 of the sliding sleeve 60, and the inner gear ring 11 is integrally formed on the inner wall of the casing 10; of course, in other embodiments, the ring gear 11 may also be fixed on the inner wall of the casing 10 by assembling and molding.

The return spring 26 is located in front of the sliding sleeve 60 of the sleeve assembly, and one end of the return spring 26 is connected to the cylinder 20 and the other end abuts against the sliding sleeve 60. In the present embodiment, the cylinder 20 is provided with an annular boss 27 protruding outward from the front end outer peripheral surface, and the front end of the return spring 26 abuts against the rear end surface of the boss 27. The sliding sleeve 60 is provided with a first inner wall surface located at the front end, a second inner wall surface located at the rear end, and a step surface connecting the first inner wall surface and the second inner wall surface, the first inner wall surface of the sliding sleeve 60 is farther away from the cylinder 20 than the second inner wall surface, a gap 66 is formed between the first inner wall surface and the outer peripheral surface of the cylinder, and the rear end of the return spring 26 is at least partially accommodated in the gap 66 and abuts against the step surface.

The sleeve component is an integral component and comprises the sliding sleeve 60, a retainer ring 64, an outer gear ring 61 and a compression spring 65, wherein the retainer ring 64, the outer gear ring 61 and the compression spring 65 are sequentially sleeved on the periphery of the front section of the sliding sleeve 60, the retainer ring 64 is fixed on the sliding sleeve 60, the outer gear ring 61 is used for being meshed with the inner gear ring 11 so that the cylinder 20 is fixed relative to the machine shell 10, one end of the compression spring 65 abuts against the outer gear ring 61, and the other end of the compression spring is connected to the sliding sleeve 60 so as to push the outer. In this embodiment, the sliding sleeve 60 is provided with an annular groove 68 recessed inward from the outer peripheral surface of the front end, and the retainer ring 64 is partially received in the groove 68 to be fixed to the sliding sleeve 60. The outer ring gear 61 is connected to the front end of the sliding sleeve 60 by a pin 67 and is axially slidable relative to the sliding sleeve 60. The compression spring 65 is located between the rear end surface of the outer gear ring 61 and the front end surface of the abutting portion 62, and the compression spring 65 has a pre-pressure to abut against the outer gear ring 61 against the retainer ring 64.

The sliding sleeve 60 is keyed to the outer wall of the cylinder 20 and is axially slidable relative to the cylinder 20. The sliding sleeve 60 is provided with a pushing portion 62 located at the middle section and an input gear 63 located at the rear section, the pushing portion 62 is used for being pushed by the switching component 70 to drive the sleeve assembly to move along the axial direction, and the input gear 63 is used for being meshed with the output gear 52 to enable the sliding sleeve 60 to drive the cylinder 20 to rotate together. When the switching member 70 drives the sleeve assembly to be positioned at the right end, the input gear 63 is meshed with the output gear 52 of the transmission mechanism so that the sleeve assembly drives the cylinder 20 to rotate together, so as to realize the hammer drill function of the multifunctional electric hammer 100, when the switching member 70 drives the sleeve assembly to be positioned at the left end, the outer gear ring 61 of the sleeve assembly is meshed with the inner gear ring 11 so that the cylinder 20 is fixed relative to the machine shell 10, and the input gear 63 is meshed with the output gear 52 of the transmission mechanism; the hammer function of the multi-functional electric hammer 100 is realized. The sleeve component is an integral component, has compact structure, can be assembled in advance before use, and is more beneficial to assembly line assembly operation and subsequent maintenance.

The intermediate gear 41, the crankshaft 40, the connecting rod 43, the cylinder 20, the piston 22, the striker 23, the intermediate member 24, and the like described above constitute an impact force transmission mechanism. The impact force transmission mechanism converts the rotational force of the motor shaft 31 in the motor 30 into the reciprocating motion of the piston 22 to apply an impact force to the operating tool, thereby performing a hammer function. The large gear 51, the output shaft 50, the input gear 63, the sliding sleeve 60, the cylinder 20, and the like as described above constitute a rotational force transmitting mechanism. The rotational force transmission mechanism transmits the rotational force of the motor shaft 31 to an operator for driving the operation tool to rotate, thereby achieving the function of the hammer drill.

The switch member 70 has a toggle button 71 located outside the housing 10 and an eccentric pin 72 protruding into the housing 10 and abutting against the rear end surface of the pushing portion 62. The eccentric pin 72 abuts against the abutting portion 62 to drive the sliding sleeve 60 to move in the axial direction, so that the sliding sleeve 60 is switched between a rotation-on state in which the input gear 63 is engaged with the output gear 52 and the outer ring gear 61 is disengaged from the inner ring gear 11, and a rotation-locking state in which the input gear 63 is disengaged from the input gear 52 and the outer ring gear 61 is engaged with the inner ring gear 11.

In the present embodiment, the output gear 52 is a small bevel gear, the input gear 63 is a large bevel gear, and the input gear 63 and the output gear 52 form a bevel gear transmission mechanism when they are engaged with each other. The sliding sleeve 60 is switched by a switching member 70, and the eccentric pin 72 of the switching member 70 has a first position located at the rightmost end in the axial direction and a second position located at the leftmost end in the axial direction. When the eccentric pin 72 is located at the first position, the large bevel gear is engaged with the small bevel gear and the outer gear ring 61 is disengaged from the inner gear ring 11, and at this time, the cylinder 20 is driven to rotate by the motor 30 and is in a rotation-on state. When the eccentric pin 72 is located at the second position, the large bevel gear is disengaged from the small bevel gear and the external gear ring 61 is engaged with the internal gear ring 11, and at this time, the cylinder 20 is fixed and cannot rotate relative to the housing 10, and is in a rotation locking state.

When the eccentric pin 72 moves from the first position to the second position, the large bevel gear is disengaged from the small bevel gear and the return spring 26 is compressed until the outer ring gear 61 is engaged with the inner ring gear 11. When the eccentric pin 72 moves from the second position to the first position, the external gear ring 61 is disengaged from the internal gear ring 11 and the return spring 26 pushes the sliding sleeve 20 until the large bevel gear is engaged with the small bevel gear. The eccentric pin 72 further has a middle position between the axially rightmost end and the axially leftmost end, when the eccentric pin 72 is located at the middle position, the large bevel gear is disengaged from the small bevel gear, and the outer gear ring 61 is disengaged from the inner gear ring 11, at this time, the sliding sleeve 20 is in a state where the rotation is neither opened nor locked, and the rotation angle of the cylinder 20 can be manually adjusted.

In the present embodiment, the multi-function electric hammer 100 has a hammer mode and a hammer drill mode. When the multifunctional electric hammer 100 is in the hammer mode, the eccentric pin 72 of the switching member 70 is located at the second position, the input gear 63 of the sliding sleeve 60 is disengaged from the output gear 52 and the outer ring gear 61 of the sliding sleeve 60 is engaged with the inner ring gear 11 of the housing 10, at this time, the cylinder 20 is fixed and cannot rotate relative to the housing 10, and the cylinder 20 can only drive the operating tool to perform the impact action. When the multifunctional electric hammer 100 is in the hammer drill mode, the eccentric pin 72 is located at the first position, the input gear 63 of the sliding sleeve 60 is engaged with the output gear 52, and the outer gear ring 61 of the sliding sleeve 60 is disengaged from the inner gear ring 11 of the housing 10, at this time, the air cylinder 20 is driven by the motor 30 to drive the operating tool to rotate, and the air cylinder 20 drives the operating tool to simultaneously perform the rotating and impacting actions.

In the present invention, the sleeve assembly is an integral assembly and includes a sliding sleeve 60, and a retainer ring 64, an outer gear ring 61 and a compression spring 65 that are sequentially sleeved on the outer periphery of the front section of the sliding sleeve 60, wherein the retainer ring 64 is fixed on the sliding sleeve 60, one end of the compression spring 65 abuts against the outer gear ring 61, and the other end is connected to the sliding sleeve 60 to push the outer gear ring 61 to abut against the retainer ring 64. The sliding sleeve 60 is provided with a pushing portion 62 at the middle section and an input gear 63 at the rear section, and the pushing portion 62 is used for being pushed by the switching component 70 to drive the sleeve assembly to move along the axial direction. When the sleeve assembly is located at the right end, the input gear 63 is meshed with the output gear 52 of the transmission mechanism so that the sleeve assembly drives the cylinder 20 to rotate together, and when the sleeve assembly is located at the left end, the outer gear ring 61 of the sleeve assembly is meshed with the inner gear ring 11 so that the cylinder 20 is fixed relative to the machine shell 10. The sleeve component is an integral component, has the effect of compact structure, can be assembled into a whole in advance before use, and is more favorable for assembly line assembly operation and subsequent maintenance. Meanwhile, the rotary switching mechanism is matched with other parts in the electric hammer through the sleeve component, so that the function conversion of the hammer and the hammer drill of the electric hammer is realized.

The present invention is not limited to the above-described embodiments. Those skilled in the art will readily appreciate that there are numerous alternatives to the sleeve assembly of the multi-function electric hammer of the present invention without departing from the spirit and scope of the invention. The protection scope of the present invention is subject to the content of the claims.

Claims

1. A multifunctional electric hammer comprises a shell, a motor, a transmission mechanism, a cylinder and a rotary switching mechanism; the motor is arranged in the shell and outputs rotating force, the transmission mechanism is driven by the motor and comprises an output shaft and an output gear positioned on the output shaft, the cylinder is supported in the shell, the rotating and switching mechanism comprises an inner gear ring fixed on the inner wall of the shell, a return spring and a sleeve assembly sleeved on the periphery of the cylinder and a switching part assembled on the shell, the return spring is positioned in front of the sleeve assembly, one end of the return spring is connected to the cylinder, the other end of the return spring abuts against the sleeve assembly, and the sleeve assembly slides left and right relative to the cylinder along the axial direction; the method is characterized in that: the sleeve assembly comprises a sliding sleeve, a check ring, an outer gear ring and a compression spring, wherein the check ring, the outer gear ring and the compression spring are sleeved on the periphery of the front section of the sliding sleeve; the sliding sleeve is provided with a pushing part positioned at the middle section and an input gear positioned at the rear section, and the pushing part is used for being pushed by the switching part to drive the sleeve component to move along the axial direction; when the switching part drives the sleeve assembly to be positioned at the right end, the input gear is meshed with the output gear of the transmission mechanism so that the sleeve assembly drives the cylinder to rotate together, and when the switching part drives the sleeve assembly to be positioned at the left end, the outer gear ring of the sleeve assembly is meshed with the inner gear ring so that the cylinder is fixed relative to the shell.

2. The multi-functional electric hammer of claim 1, wherein: the sliding sleeve is connected to the outer wall of the cylinder by a pin, and the outer ring gear is connected to the front end of the sliding sleeve by a pin and slides axially relative to the sliding sleeve.

3. The multi-functional electric hammer of claim 1, wherein: the sliding sleeve is provided with an annular groove which is inwards sunken from the peripheral surface of the front end, the retainer ring is partially contained in the groove to be fixed on the sliding sleeve, and the compression spring is positioned between the rear end face of the outer gear ring and the front end face of the abutting portion to abut against and push the outer gear ring to abut against the retainer ring.

4. The multi-functional electric hammer of claim 1, wherein: the cylinder is provided with an annular bulge part which protrudes outwards from the peripheral surface of the front end, and the front end of the return spring abuts against the rear end face of the bulge part; the sliding sleeve is provided with a first inner wall face located at the front end, a second inner wall face located at the rear end and a step face connecting the first inner wall face and the second inner wall face, the first inner wall face of the sliding sleeve is far away from the cylinder compared with the second inner wall face, a gap is formed between the first inner wall face and the outer peripheral surface of the cylinder, and at least part of the rear end of the reset spring is contained in the gap and is abutted against the step face.

5. The multi-functional electric hammer of claim 1, wherein: the output gear is a small bevel gear, the input gear is a large bevel gear, and a bevel gear transmission mechanism is formed when the input gear is meshed with the output gear.

6. The multi-functional electric hammer of claim 5, wherein: the switching component is provided with an eccentric pin which protrudes into the shell and abuts against the rear end face of the abutting part, the eccentric pin abuts against the abutting part to drive the sliding sleeve to move axially, and the sliding sleeve is switched between a state that the input gear is meshed with the output gear and the outer gear ring is separated from the inner gear ring and a state that the input gear is separated from the input gear and the outer gear ring is meshed with the inner gear ring.

7. The multi-functional electric hammer of claim 6, wherein: the sliding sleeve is switched by the switching part, the eccentric pin of the switching part is provided with a first position located at the rightmost end in the axial direction and a second position located at the leftmost end in the axial direction, when the eccentric pin is located at the first position, the input gear is meshed with the output gear, the outer gear ring is separated from the inner gear ring, and at the moment, the air cylinder is driven to rotate by the motor; when the eccentric pin is located at the second position, the input gear is separated from the output gear, the outer gear ring is meshed with the inner gear ring, and at the moment, the cylinder is fixed relative to the machine shell and cannot rotate.

8. The multi-functional electric hammer of claim 7, wherein: when the eccentric pin moves from the first position to the second position, the input gear is separated from the output gear and the return spring is compressed until the outer gear ring is meshed with the inner gear ring; when the eccentric pin moves from the second position to the first position, the outer gear ring is separated from the inner gear ring, and the return spring pushes the sliding sleeve until the input gear is meshed with the output gear.

9. The multi-functional electric hammer of claim 7, wherein: the eccentric pin is also provided with a middle position between the axial rightmost end and the axial leftmost end, and when the eccentric pin is positioned at the middle position, the input gear is separated from the input and output gear, and the outer gear ring is separated from the inner gear ring.

10. The multi-functional electric hammer of claim 1, wherein: the inner gear ring is positioned in front of the outer gear ring, and the inner gear ring is integrally formed on the inner wall of the casing or assembled and fixed on the inner wall of the casing.