CN112677112A

CN112677112A - Electric hammer

Info

Publication number: CN112677112A
Application number: CN202011636553.8A
Authority: CN
Inventors: 候维平
Original assignee: Jiangsu Dongcheng Tools Technology Co Ltd
Current assignee: Jiangsu Dongcheng Tools Technology Co Ltd
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2021-04-20

Abstract

The invention discloses an electric hammer, which comprises a shell, a motor positioned in the shell, and an impact assembly and a rotating assembly which are driven by the motor, wherein the impact assembly comprises a cylinder and a piston arranged in the cylinder in a sliding manner; the rotating assembly comprises an output shaft connected to the front end of the motor and a planet carrier sleeved at the rear end of the cylinder, the motor drives the output shaft to rotate, the output shaft penetrates through the planet carrier and drives the planet to drive the cylinder to rotate, and the piston is clamped in the cylinder and rotates together with the cylinder; the output shaft is connected to the rear end of the piston and drives the piston to reciprocate, and the motor, the output shaft and the cylinder are located on the same rotation axis, so that the electric hammer is beneficial to holding and miniaturization.

Description

Electric hammer

[ technical field ] A method for producing a semiconductor device

The invention relates to the field of electric tools, in particular to an electric hammer for drilling or chiseling holes in concrete, floor slabs, brick walls and stone.

[ background of the invention ]

The traditional electric hammer adopts a crank connecting rod or a swing rod bearing mechanism to drive a piston to do reciprocating motion, and then the piston drives a hammer in a cylinder to perform impact output.

Please refer to chinese patent publication No. CN101312807B of bosch limited, which discloses an electric hammer, wherein a motor drives an intermediate shaft to rotate, the intermediate shaft is disposed below the motor in parallel, the intermediate shaft is provided with a swing rod bearing and a rotation input gear, the intermediate shaft drives a swing rod of the swing rod bearing to swing and drive a piston in a cylinder to reciprocate, a driving gear engaged with the rotation input gear is fixedly disposed on the cylinder, the rotation input gear drives the cylinder to rotate together through the driving gear, but the volume of the electric hammer is increased by the way of driving impact through the swing rod bearing, and the weight of the swing rod bearing is relatively heavy. Please refer to chinese utility model patent publication No. CN2860757Y of zhejiang sea king electrical apparatus limited to disclose an electric hammer, wherein a motor is perpendicular to a cylinder and is disposed below the cylinder, the motor drives an eccentric shaft to rotate, the eccentric shaft drives a piston to reciprocate through a connecting rod, the piston pushes a hammer to perform impact output, but the electric hammer needs to vacate a larger space to accommodate the structure of the crank-connecting rod, and the weight of the crank-connecting rod is larger.

Therefore, there is a need to design a new electric hammer to reduce the volume and weight of the electric hammer.

[ summary of the invention ]

To solve the above problems, the present invention provides a compact and easy-to-hold electric hammer.

In order to solve the technical problems, the invention adopts the following technical scheme: an electric hammer comprises a shell, a motor positioned in the shell, and an impact assembly and a rotating assembly which are driven by the motor, wherein the impact assembly comprises a cylinder and a piston arranged in the cylinder in a sliding manner; the rotating assembly comprises an output shaft connected to the front end of the motor and a planet carrier sleeved at the rear end of the cylinder, the motor drives the output shaft to rotate, the output shaft penetrates through the planet carrier and is meshed with the planet carrier through a gear, the planet carrier drives the cylinder to synchronously rotate, and the piston is clamped in the cylinder and rotates together with the cylinder; the piston is equipped with the holding tank that runs through the rear end face and with the holding tank intercommunication and run through a pair of through-hole of periphery, the front end of output shaft is inserted and is located in the holding tank, just the output shaft is equipped with the wave form groove that is located the front end periphery, the wave form groove is followed output shaft periphery end to end and have axial front end and axial rear end, the impact subassembly include the part hold in the steel ball of wave form inslot, another part of steel ball hold in the through-hole, the output shaft drives when rotatory the piston makes reciprocating motion along the axial, the motor, the output shaft reaches the cylinder is located same rotation axis.

The further improvement scheme is as follows: the rotating assembly comprises a planet wheel assembly connected to the front end of the motor, and the planet wheel assembly comprises an inner gear ring fixed in the shell and a plurality of first planet wheels meshed with the inner wall of the inner gear ring; the output shaft is provided with an accommodating groove penetrating through the rear end face and a mounting seat communicated with the accommodating groove and penetrating through the periphery, the motor is provided with a motor shaft extending into the accommodating groove, and a plurality of first planet gears are fixed in the corresponding mounting seats in a relative rotating mode and are meshed with the motor shaft in the accommodating groove.

The further improvement scheme is as follows: the planet wheel assembly comprises a sun wheel fixedly arranged on the output shaft and a second planet wheel meshed with the sun wheel, and the sun wheel is positioned in front of the first planet wheel and the mounting seat; the planet carrier is provided with a pin column positioned at the rear end, the second planet wheel is supported on the pin column and meshed with the inner gear ring, and the output shaft drives the planet carrier to rotate together through the second planet wheel.

The further improvement scheme is as follows: the rotating assembly further comprises a spring sleeved on the planet carrier and a transmission sleeve sleeved on the periphery of the cylinder, the transmission sleeve is located in front of the planet carrier and connected with the cylinder through a key groove, the front end of the planet carrier is meshed and abutted to the rear end of the transmission sleeve, the front end of the spring is abutted against the planet carrier, the rear end of the spring is abutted against the shell, and the planet carrier is abutted to the rear end of the transmission sleeve; the planet carrier drives the cylinder to rotate together through the transmission sleeve.

The further improvement scheme is as follows: one of the outer wall of the piston and the inner wall of the cylinder is provided with a slot parallel to the axis of the cylinder, the other one is provided with a protrusion clamped in the slot, and the cylinder and the piston synchronously rotate through clamping of the protrusion and the slot.

The further improvement scheme is as follows: the piston is equipped with paste lean on in the sliding part of cylinder inner wall and certainly the inside sunken ring channel of sliding part, strike the subassembly including being located sealing washer in the ring channel, the sealing washer support lean on in the inner wall of cylinder, when the piston is located the rearmost end of stroke, protruding with the slot all is located the sealing washer with the ring channel rear side.

The further improvement scheme is as follows: the slot is formed by extending forwards from the rear end of the inner wall of the cylinder, the protrusion is a ball accommodated in the through hole of the piston, the lower end of the protrusion abuts against the steel ball, and the upper end of the protrusion is accommodated in the slot.

The further improvement scheme is as follows: the rotating assembly comprises a rotating sleeve assembly vertically connected below the front end of the air cylinder, the rotating sleeve assembly comprises a rotating sleeve, an output gear and a clamping assembly, the output gear and the clamping assembly are fixedly held on the rotating sleeve, the rotating assembly further comprises an input gear fixedly held at the front end of the air cylinder, and the input gear is in meshed connection with the output gear.

The further improvement scheme is as follows: the impact assembly is characterized by further comprising an impact rod and a corner supporting assembly, wherein the impact rod and the corner supporting assembly are arranged in an arc shape, the impact rod is located between the cylinder and the rotating sleeve, the corner supporting assembly is located on the outer side of the impact rod and supports the sliding sleeve in the shell, and the impact rod is arranged on the inner wall of the sliding sleeve in a clockwise or anticlockwise sliding mode.

Compared with the prior art, the invention has the following beneficial effects: connect the output shaft transmission in motor the place ahead, be connected with the planet carrier on the output shaft, the planet carrier cover is located the cylinder rear end, the output shaft runs through planet carrier and drive planet carrier and drives the cylinder synchronous revolution, motor, output shaft and cylinder have the same rotation axis, and the structure is compacter and has the miniaturization, and the electric hammer becomes more small and exquisite, also makes the shell can make the sleeve shape that the operator of being convenient for gripped simultaneously, has changed the mode that must grip the handle from the electric hammer rear end.

[ description of the drawings ]

Fig. 1 is a sectional view of a piston of an electric hammer of the present invention in a rear end position;

fig. 2 is a sectional view of the piston of the electric hammer of the present invention in a front end position;

FIG. 3 is an enlarged view of a portion of FIG. 1;

FIG. 4 is a cross-sectional view of the motor and planet wheel assembly of the electric hammer of the present invention;

FIG. 5 is a perspective view of a portion of the planet wheel assembly of FIG. 4;

FIG. 6 is a perspective view of the cylinder, clutch assembly and a portion of the planetary wheel assembly of the electric hammer of the present invention;

FIG. 7 is a cross-sectional view of the cylinder liner assembly and clutch assembly of the electric hammer of the present invention;

FIG. 8 is a cutaway view of the cylinder and drive sleeve of the electric hammer of the present invention;

fig. 9 is a perspective view of the cylinder of the electric hammer of the present invention;

fig. 10 is a front view of the piston of the hammer of the present invention.

[ detailed description ] embodiments

The following further describes a specific embodiment of the present invention with reference to the drawings and examples, wherein the embodiment of the electric hammer 100 is described in detail by taking the electric hammer as an example.

Referring to fig. 1 to 10, which are schematic views of an electric hammer 100 according to the present invention, an output direction of a motor 1 is defined as a front end, the electric hammer 100 includes a housing 101, the motor 1 accommodated in the housing 101, a transmission assembly 2 driven by the motor 1, and a chisel head detachably mounted at an end of the transmission assembly 2, the transmission assembly 2 is accommodated in the housing 101 and includes an impact assembly 20 and a rotation assembly 50, the motor 1 drives the impact assembly 20 to compress air and eject the impact chisel head to impact and output, and the motor 1 drives the rotation assembly 50 to drive the chisel head to rotate and output.

The rotating assembly 50 includes a planetary wheel assembly 51 drivingly connected to the front end of the motor 1, a clutch assembly 52, a cylinder liner assembly 53 and a rotating sleeve assembly 54. The motor 1 is provided with a motor shaft 1a extending along the front-back direction, and the front end of the motor shaft 1a is meshed with the planet wheel assembly 51; the clutch assembly 52 is connected to the front of the planet wheel assembly 51 in a transmission manner, and the cylinder sleeve assembly 53 is sleeved with the clutch assembly 52 and drives the cylinder sleeve assembly 53 to rotate together; the electric hammer 100 in this embodiment is an angular electric hammer, the output direction of the chisel head of the electric hammer 100 is defined as downward, the rotating sleeve assembly 54 is drivingly connected to the lower portion of the front end of the cylinder sleeve assembly 53, the rotating sleeve assembly 54 and the cylinder sleeve assembly 53 are perpendicular to each other and extend downward toward the outside of the housing 101, and the chisel head is accommodated in the rotating sleeve assembly 54 and rotates together with the rotating sleeve assembly 54.

Referring to fig. 1 and 7, the cylinder sleeve assembly 53 includes a cylinder 531 and an input gear 532 sleeved at a front end of the cylinder 531, the input gear 532 is fixed to the cylinder 531 and rotates together with the cylinder 531, and the cylinder 531 is supported in the housing 101 by two bearings fixed at a front-rear interval.

Referring to fig. 4 to 6, the planetary wheel assembly 51 includes an output shaft 511, an inner gear 512, a first planetary wheel 513, a sun gear 514, a second planetary wheel 515 and a planet carrier 516; the rear end of the output shaft 511 is supported in the housing 101 through a bearing and the front end is supported on the inner wall of the cylinder 531; the inner gear ring 512 is fixedly connected in the shell 101, and the inner wall of the inner gear ring 512 is meshed with the first planet wheel 513; the output shaft 511 is provided with a containing groove 511a penetrating through the rear end face and a plurality of mounting seats 511b communicating with the containing groove and penetrating through the periphery, and in the embodiment, two mounting seats 511b are arranged in the circumferential direction of the output shaft 511; the axial front end of the motor shaft 1a is inserted into the housing groove 511a, and the two first planet gears 513 are relatively rotatably pinned in the mounting seat 511b and engaged with the motor shaft 1a in the housing groove 511 a; the motor shaft 1a drives the output shaft 511 to rotate through the first planet gear 513. The sun gear 514 is disposed in front of the first planetary gear 513 and fixed to the output shaft 511, and the sun gear 514 and the output shaft 511 rotate together. The sun gear 514 and the outer ring of the output shaft 511 are in interference fit in the present embodiment, and the sun gear 514 and the output shaft 511 may be integrally formed in other embodiments; two sides of the second planet wheel 515 are respectively meshed with the sun wheel 514 and the inner gear ring 512; the planet carrier 516 is sleeved on the periphery of the rear end of the cylinder 531 and drives the cylinder 531 to rotate, in the embodiment, the planet carrier 516 drives the cylinder 531 to rotate through the clutch component 52, the output shaft 511 penetrates through the planet carrier 516 and extends into the cylinder 531, three pins 516a penetrating through and supporting the second planet wheel 515 are fixedly inserted into the rear end of the planet carrier 516, and the second planet wheel 515 drives the planet carrier 516 to rotate together through the pins 516 a.

Referring to fig. 1, 7 and 8, the clutch assembly 52 includes a spring 522 and a transmission sleeve 521 sleeved on the outer circumference of the cylinder 531; the transmission sleeve 521 is connected with the cylinder 531 through a key slot and rotates together, and the front end of the transmission sleeve 521 abuts against a rear bearing supporting the cylinder 531. The front end of the planet carrier 516 is meshed with the rear end of the transmission sleeve 521, that is, the front end surface of the planet carrier 516 and the rear end surface of the transmission sleeve 521 are provided with concave-convex structures 521a which are clamped with each other. The spring 522 is sleeved on the planet carrier 516, the front end of the spring 522 abuts against the planet carrier 516, the other end of the spring 522 abuts against the shell 101, the rear end of the planet carrier 516 is provided with an annular step abutting against the cylinder 531, and the spring 522 further pushes the cylinder 531 forwards. When the electric hammer 100 works under normal load, the planet carrier 516 drives the air cylinder 531 to rotate through the transmission sleeve 521, when the electric hammer 100 works under overload, the air cylinder 531 and the transmission sleeve 521 stop rotating, the planet carrier 516 overcomes the pressure of the spring 522 and is separated from the meshing of the transmission sleeve 521, the transmission of the motor 1 is separated from the rotation of the air cylinder 531 when the electric hammer 100 works under overload, and the motor is prevented from being burnt.

Referring to fig. 1 and fig. 3, the rotating sleeve assembly 54 includes a rotating sleeve 541, an output gear 542 and a clamping assembly 543 fixed on the rotating sleeve 541. The rotating sleeve 541 is perpendicular to the air cylinder 531 and is installed at the front end of the casing 101, and the clamping assembly 543 is used for clamping a chisel head; the output gear 542 is fixed on the upper end of the rotary sleeve 541 and is engaged with the input gear 532, and the input gear 532 drives the rotary sleeve 541 to rotate together through the output gear 542.

Referring to fig. 1 to 5, the impact assembly 20 includes a piston 21, a steel ball 21a, a hammer 22, an impact rod 23, a hammer locking assembly 24, a corner support assembly 25, and the cylinder 531. The piston 21, the impact hammer 22 and the hammer locking assembly 24 are sequentially arranged on the inner wall of the cylinder 531 from back to front; the piston 21 is provided with an accommodating groove penetrating through the rear end face and a pair of through holes communicated with the accommodating groove and penetrating through the periphery, and a part of the steel ball 21a is accommodated in the through holes; the front end of the output shaft 511 is inserted into the receiving groove, and the output shaft 511 is provided with a wave-shaped groove 511c located at the outer periphery of the front end, the wave-shaped groove 511c is connected end to end along the outer periphery of the output shaft 511 and has an axial front end and an axial rear end, another part of the steel ball 21a is received in the wave-shaped groove 511c, and the piston 21 is held on the wave-shaped groove 511c by the steel ball 21a and slides between the axial front end and the axial rear end of the wave-shaped groove 511 c; one of the outer wall of the piston 21 and the inner wall of the cylinder 531 is provided with a slot, and the other is provided with a protrusion clamped in the slot, so that the piston 21 and the cylinder 531 rotate synchronously, as shown in fig. 9 to 10, in this embodiment, the inner wall of the cylinder 531 is provided with a slot 531a extending from the rear end forward in the axial direction, the outer periphery of the piston 21 is provided with a protrusion 21b clamped with the slot 531a, the piston 21 is clamped in the cylinder 531 through the protrusion 21b and rotates synchronously with the cylinder 531, the protrusion 21b is a ball accommodated in a through hole of the piston 21, the lower end of the protrusion 21b abuts against the steel ball 21a, and the upper end of the protrusion is accommodated in the slot 531a, and the ball is clamped with the slot 531a, so that rolling friction replaces sliding friction, which is favorable for reducing wear to the cylinder 531.

The rotating speed of the output shaft 511 is S1, the rotating speed S1 of the output shaft 511 is reduced by the planetary wheel assembly 51 to obtain the rotating speed S2 of the planet carrier 516 and the air cylinder 531, the rotating speed S1 is greater than that S2, the speed difference between the output shaft 511 and the air cylinder 531 causes the wave-shaped groove 511c on the output shaft 511 to continuously drive the piston 21 to reciprocate, further the piston 21 compresses air to drive the impact hammer 22 to impact, the impact hammer 22 transmits the impact force to the impact rod 23, and the impact rod 23 drives the chisel head to perform impact output. Piston 21 in this embodiment has the sliding part that the inner wall of cylinder 531 leans on, the sliding part is equipped with inside sunken ring channel 21c, strike subassembly 20 and be equipped with and be located sealing washer (not shown) in the ring channel, the sealing washer support lean on in the inner wall of cylinder to increase the gas tightness piston 21 is located the rearmost end of stroke, arch 21b all is located with slot 531a the sealing washer with ring channel 21c rear side is favorable to preventing that the slot from leaking the air of compression, and then reaches better airtight, has increased electric hammer 100's impact force.

The cylinder 531 is provided with a step protruding inwards from the inner wall of the front end and an elastic collar located at the rear side of the step and clamping the inner wall, the lock hammer assembly 24 is axially limited between the step and the elastic collar, and the lock hammer assembly 24 comprises a front gasket 241 abutted against the step, a rear gasket 242 abutted against the elastic collar, and a rubber ring 243 located between the front gasket 241 and the rear gasket 242. The hammer punch 22 has a large diameter portion abutting against the inner wall of the cylinder 531 and a small diameter portion located at the front end of the large diameter portion and impacting the impact rod 23, an annular protrusion is arranged at the front end of the small diameter portion, the diameter of the annular protrusion is larger than the inner diameter of the rubber ring 243, when the electric hammer 100 is in an idle load state, the piston 21 drives the hammer punch 22 forward, and the annular protrusion is clamped at the front end of the rubber ring 243 and cannot slide backward any more.

Referring to fig. 3, the impact rod 23 is arc-shaped and reciprocates between the cylinder 531 and the rotating sleeve 541, the corner support assembly 25 is sleeved on the impact rod 23 and supported in the housing 101, and the corner support assembly 25 includes a support sleeve 251, a damping ring 252 and a sliding sleeve 253, all of which are arc-shaped tubular; the supporting sleeve 251 is directly supported in the housing 101, and the rear end of the supporting sleeve 251 abuts against the front washer 241 and the other front end abuts against the housing 101, i.e. the supporting sleeve 251 abuts against the cylinder 531 through the locking hammer assembly 24; the damping ring 252 is fixed on the inner wall of the supporting sleeve 251 and extends along the arc-shaped inner wall of the supporting sleeve 251; the inner wall of the supporting sleeve 251 is provided with a blocking wall which protrudes inwards and is abutted against the rear end of the damping ring 252 so as to prevent the damping ring 252 from sliding towards the rear end; the sliding sleeve 253 is fixed in the damping ring 252; the sliding sleeve 253 is sleeved on the impact rod 23, the impact rod 23 slides clockwise or anticlockwise along the inner wall of the sliding sleeve 253, when the small-diameter part of the punch hammer 22 impacts the impact rod 23, the impact rod 23 slides clockwise along the inner wall of the sliding sleeve 253, the rear end of the impact rod 23 is intermittently inserted into the air cylinder 531, and the front end of the impact rod 23 is intermittently inserted into the rotating sleeve 541 and impacts the chisel head; the impact rod 23 is provided with a convex part 23a protruding outwards from the periphery of the front end, when the impact rod 23 slides anticlockwise, the convex part 23a is clamped on the end surface of the sliding sleeve 253 and does not contact the damping ring 252, the convex part 23a transmits the reverse impact force of the impact rod 23 to the sliding sleeve 253, the damping ring 252 is an arc rubber sleeve, the damping ring 252 buffers the impact force applied to the sliding sleeve 253 and then transmits the buffered impact force to the support sleeve 251, namely, the damping ring 252 performs primary damping; the supporting sleeve 251 transmits impact force to the front gasket 241, the impact force on the front gasket 241 is transmitted to the rear gasket 242 after being buffered by the rubber ring 24, and further the rear gasket 242 transmits the impact force to the cylinder 531 through an elastic collar, namely the rubber ring 24 performs secondary damping; the rear end of the planet carrier 516 is provided with an annular step abutting against the air cylinder 531, the air cylinder 531 transmits impact force to the planet carrier 516, the spring 522 buffers the impact force of the planet carrier 516 and then transmits the impact force to the shell 101, and the spring 522 performs third-stage damping. In this embodiment, the dynamic accumulation three-level shock absorption buffers the reverse impact of the impact rod 23, which is beneficial to increase the operation comfort of the electric hammer 100. In other embodiments, the third stage of damping may also be implemented by disposing a snap spring (not shown) at the front end of the planet carrier 516, the snap spring being clamped to the outer ring of the cylinder 531, the cylinder 531 transmitting the impact force to the planet carrier 516 through the snap spring, and the spring 522 buffering the impact force of the planet carrier 516 and then transmitting the impact force to the casing 101. In other manners, the supporting sleeve 251 may be eliminated, and the damping ring 252 may be directly supported in the casing 101, wherein the damping ring 252 is directly abutted against the front gasket 241.

In the electric hammer 100 of the present invention, the output shaft 511 is inserted into the accommodating groove of the piston 21, the periphery of the piston 21 is provided with a pair of through holes penetrating to the accommodating groove, the periphery of the front end of the output shaft 511 is provided with a wave-shaped groove 511c, a steel ball 21a is clamped between the through holes and the wave-shaped groove 511c, the steel ball 21a moves between the axial front end and the axial rear end of the wave-shaped groove 511c when the output shaft rotates to drive the piston 21 to reciprocate, and a mechanism for driving the piston 21 to reciprocate is intensively arranged inside the piston 21, so that the electric hammer 100 has a compact structure and is miniaturized, and in addition, the use of a crank connecting rod and a swing rod bearing with large weight is avoided, so that the weight of the electric hammer 100 itself is greatly reduced. The output shaft 511 is in transmission connection with the front of the motor 1, the output shaft 511 is connected with the planet carrier 516, the planet carrier 516 is sleeved at the rear end of the air cylinder 531, the output shaft 511 penetrates through the planet carrier 516 and drives the planet carrier 516 to drive the air cylinder 531 to synchronously rotate, the motor 1, the output shaft 511 and the air cylinder 531 have the same rotation axis, the electric hammer 100 is more compact in structure and miniaturized, and meanwhile, the shell 101 can be made into a sleeve shape which is convenient for an operator to hold, so that the mode that the handle must be held from the rear end of the electric hammer 100 is changed. The damping ring 252 in the corner supporting component 25, the rubber ring 243 in the hammer locking component 24 fixed at the front end of the air cylinder 531 and the spring 522 sleeved on the periphery of the air cylinder 531 are accumulated to perform three-level damping, so that the vibration of the electric hammer 100 is effectively reduced, the operation comfort of an operator is improved, meanwhile, the hard collision of internal parts of the electric hammer 100 is reduced, and the service life of the electric hammer 100 is prolonged.

Claims

1. An electric hammer comprises a shell, a motor positioned in the shell, and an impact assembly and a rotating assembly which are driven by the motor, wherein the impact assembly comprises a cylinder and a piston arranged in the cylinder in a sliding manner; the method is characterized in that: the rotating assembly comprises an output shaft connected to the front end of the motor and a planet carrier sleeved at the rear end of the cylinder, the motor drives the output shaft to rotate, the output shaft penetrates through the planet carrier and is meshed with the planet carrier through a gear, the planet carrier drives the cylinder to synchronously rotate, and the piston is clamped in the cylinder and rotates together with the cylinder; the piston is equipped with the holding tank that runs through the rear end face and with the holding tank intercommunication and run through a pair of through-hole of periphery, the front end of output shaft is inserted and is located in the holding tank, just the output shaft is equipped with the wave form groove that is located the front end periphery, the wave form groove is followed output shaft periphery end to end and have axial front end and axial rear end, the impact subassembly include the part hold in the steel ball of wave form inslot, another part of steel ball hold in the through-hole, the output shaft drives when rotatory the piston makes reciprocating motion along the axial, the motor, the output shaft reaches the cylinder is located same rotation axis.

2. The electric hammer of claim 1, wherein: the rotating assembly comprises a planet wheel assembly connected to the front end of the motor, and the planet wheel assembly comprises an inner gear ring fixed in the shell and a plurality of first planet wheels meshed with the inner wall of the inner gear ring; the output shaft is provided with an accommodating groove penetrating through the rear end face and a mounting seat communicated with the accommodating groove and penetrating through the periphery, the motor is provided with a motor shaft extending into the accommodating groove, and a plurality of first planet gears are fixed in the corresponding mounting seats in a relative rotating mode and are meshed with the motor shaft in the accommodating groove.

3. The electric hammer of claim 2, wherein: the planet wheel assembly comprises a sun wheel fixedly arranged on the output shaft and a second planet wheel meshed with the sun wheel, and the sun wheel is positioned in front of the first planet wheel and the mounting seat; the planet carrier is provided with a pin column positioned at the rear end, the second planet wheel is supported on the pin column and meshed with the inner gear ring, and the output shaft drives the planet carrier to rotate together through the second planet wheel.

4. An electric hammer according to claim 3, wherein: the rotating assembly further comprises a spring sleeved on the planet carrier and a transmission sleeve sleeved on the periphery of the cylinder, the transmission sleeve is located in front of the planet carrier and connected with the cylinder through a key groove, the front end of the planet carrier is meshed and abutted to the rear end of the transmission sleeve, the front end of the spring is abutted against the planet carrier, the rear end of the spring is abutted against the shell, and the planet carrier is abutted to the rear end of the transmission sleeve; the planet carrier drives the cylinder to rotate together through the transmission sleeve.

5. The electric hammer of claim 2, wherein: one of the outer wall of the piston and the inner wall of the cylinder is provided with a slot parallel to the axis of the cylinder, the other one is provided with a protrusion clamped in the slot, and the cylinder and the piston synchronously rotate through clamping of the protrusion and the slot.

6. The electric hammer of claim 5, wherein: the piston is equipped with paste lean on in the sliding part of cylinder inner wall and certainly the inside sunken ring channel of sliding part, strike the subassembly including being located sealing washer in the ring channel, the sealing washer support lean on in the inner wall of cylinder, when the piston is located the rearmost end of stroke, protruding with the slot all is located the sealing washer with the ring channel rear side.

7. The electric hammer of claim 6, wherein: the slot is formed by extending forwards from the rear end of the inner wall of the cylinder, the protrusion is a ball accommodated in the through hole of the piston, the lower end of the protrusion abuts against the steel ball, and the upper end of the protrusion is accommodated in the slot.

8. The electric hammer of claim 1, wherein: the rotating assembly comprises a rotating sleeve assembly vertically connected below the front end of the air cylinder, the rotating sleeve assembly comprises a rotating sleeve, an output gear and a clamping assembly, the output gear and the clamping assembly are fixedly held on the rotating sleeve, the rotating assembly further comprises an input gear fixedly held at the front end of the air cylinder, and the input gear is in meshed connection with the output gear.

9. The electric hammer of claim 8, wherein: the impact assembly is characterized by further comprising an impact rod and a corner supporting assembly, wherein the impact rod and the corner supporting assembly are arranged in an arc shape, the impact rod is located between the cylinder and the rotating sleeve, the corner supporting assembly is located on the outer side of the impact rod and supports the sliding sleeve in the shell, and the impact rod is arranged on the inner wall of the sliding sleeve in a clockwise or anticlockwise sliding mode.