Multi-speed adjustable electric hammer with stable structure

Abstract

The application discloses a multi-gear adjusting type electric hammer with stable structure, which comprises a casing, a motor, a motion conversion mechanism, an impact mechanism and a rotating sleeve arranged in the casing. The motion conversion mechanism comprises a spline shaft, a swing lever bearing and a transmission assembly. One end of the spline shaft is inserted into the central hole of the swing lever bearing and can be switched and moved among a first position, a second position and a third position. The transmission assembly comprises a pinion shaft and an axially limited intermediate shaft sleeve. The intermediate shaft sleeve is meshed and connected with the motor shaft of the motor. The first end of the pinion shaft is axially movably inserted into the intermediate shaft sleeve and the relative rotation of the two is limited. An elastic member is arranged between the pinion shaft and the intermediate shaft sleeve. The elastic member drives the pinion shaft to move along the axial direction to one side of the spline shaft, and the second end of the pinion shaft is inserted into the central hole of the swing lever bearing. When the spline shaft moves, the pinion shaft can be pushed to move along the axial direction to one side of the intermediate shaft sleeve. After the pinion shaft moves leftward or rightward, the second end is in transmission connection with the spline shaft and / or the swing lever bearing.

Description

Technical Field

[0001] The invention relates to an electric hammer, in particular to a multi-speed adjustable electric hammer with a stable structure. Background Art

[0002] An electric hammer, also known as a hammer drill, is a widely used chiseling tool. A transmission mechanism drives a piston to reciprocate compressed air within a cylinder. The cyclical changes in air pressure within the cylinder drive the hammer inside the cylinder to strike the top of the drill bit back and forth, causing the drill bit to rotate while also receiving a reciprocating hammering motion parallel to the drill bit, achieving both striking and drilling functions simultaneously.

[0003] Most electric hammers currently on the market have only two gears (hammer, hammer-drill or rotary, hammer-drill), or require adjusting knobs in two places to achieve three or four gears (drill, hammer-drill, chisel, and adjustable chisel). In order to develop an electric hammer that can achieve four gears by adjusting a dial.

[0004] For example, the electric hammer with patent publication number CN211729047U includes a motor, which rotates around the motor shaft; an output shaft, which is used to at least partially accommodate a working head and drive the working head to selectively output rotation around the output axis and / or reciprocating motion along the output axis; a motion conversion mechanism, which is used to receive power from the motor, and the motion conversion mechanism includes an intermediate shaft, a gear mechanism for transmitting power between the intermediate shaft and the output shaft, and a rocker bearing sleeved on the intermediate shaft and swinging back and forth, and the intermediate shaft can selectively move along its axial direction to a first position, a second position, and a third position; an impact mechanism, which is used to receive power transmitted by the motion conversion mechanism, and the impact mechanism includes a rocker shaft receiving the power. A cylinder that bears force and reciprocates along the working axis, a hammer that cooperates with the cylinder, and a striker rod that cooperates with the hammer, and an impact mechanism is used to drive the working head to reciprocate along the output axis; wherein, when the intermediate shaft moves to the first position, the output shaft only outputs reciprocating motion, when the intermediate shaft moves to the second position, the output shaft outputs both reciprocating motion and rotation, and when the intermediate shaft moves to the third position, the output shaft only outputs rotation; the electric hammer also includes a bearing bracket supporting the cylinder and a support bearing supporting the intermediate shaft, when the intermediate shaft is in the third position, the support bearing abuts against the bearing bracket, and a gear shaft is provided at the output end of the motor, the gear shaft is connected to the intermediate shaft and / or the rocker bearing, and the intermediate shaft and the rocker bearing are selectively connected to the gear shaft.

[0005] Problems with existing electric hammers include: 1. The gear shaft is connected to the intermediate shaft and / or the rocker arm bearing. The intermediate shaft and the rocker arm bearing are selectively connected to the gear shaft. When the intermediate shaft moves to adjust the function, the gear shaft moves with the function switching. However, to ensure the stability of the forward and backward movement without affecting the meshing of the gear shaft with the gear on the motor output shaft, a needle roller bearing is provided in the rocker arm bearing to support the gear shaft. However, during the forward and backward movement of the gear shaft, the meshing of the gear shaft with the gear on the motor output shaft remains unstable, which does not effectively solve the problem of maintaining stable meshing of the gear shaft with the gear on the motor output shaft. 2. To ensure the transmission positioning of the intermediate shaft, a needle roller bearing is provided at one end of the gear shaft, and one end of the intermediate shaft is inserted into the needle roller bearing. However, during the function switching, the gear shaft moves forward and backward, resulting in a lack of stability of the gear shaft itself, causing the needle roller bearing installed in the gear shaft to become unstable, and increasing the misalignment of the intermediate shaft during transmission. Summary of the Invention

[0006] In view of the above-mentioned shortcomings that the gear shaft will move with the switching of functions, which makes the engagement of the gear with the gear on the motor output shaft unstable, the present invention provides a multi-speed adjustable electric hammer with a stable structure.

[0007] The technical solution adopted by the present invention to solve the above technical problems is: a multi-speed adjustable electric hammer with a stable structure, including a casing, in which a motor, a motion conversion mechanism, an impact mechanism and a rotating sleeve for connecting a working head are arranged. The motion conversion mechanism is connected to the motor and transmits the output power of the motor to the impact mechanism and the rotating sleeve. The impact mechanism is used to drive the working head to reciprocate along the axis direction of the rotating sleeve. The rotating sleeve is used to drive the working head to rotate. The motion conversion mechanism includes a spline shaft for driving the rotating sleeve to rotate, a rocker bearing for driving the impact mechanism to reciprocate and impact, and a transmission assembly. The rocker bearing is located between the spline shaft and the transmission assembly and has a center hole. The spline shaft is rotatably installed in the casing, and one end of the spline shaft is inserted into the center hole of the rocker bearing, and can be in the first position, the second position and the third position along the axial direction. The cam is connected to the motor shaft by a toothed disc to move the gears, and the cam is connected to the gear train by a toothed disc to move the gears, and the cam is connected to the gear train by a toothed disc to move the gears.

[0008] When the spline shaft moves to the first position, the second end of the pinion shaft is only connected to the spline shaft, and the working head can only output rotational power to the outside. When the spline shaft moves to the second position, the second end of the pinion shaft is simultaneously connected to the spline shaft and the rocker bearing, and the working head can simultaneously output rotational and reciprocating impact power to the outside. When the spline shaft moves to the third position, the second end of the pinion shaft is only connected to the rocker bearing, and the working head can only output impact power to the outside.

[0009] A further preferred technical solution of the present invention is that a first bearing and a second bearing are respectively provided between the front and rear ends of the intermediate sleeve and the casing, and the first bearing and the second bearing sleeve are provided at the front and rear ends of the intermediate sleeve for supporting the intermediate sleeve.

[0010] A further preferred technical solution of the present invention is: the rocker bearing is fixedly installed in the casing, a third bearing is fixedly installed in the center hole of the rocker bearing, one end of the spline shaft is inserted into the center hole and passes through the center of the third bearing, and the third bearing is used to support one end of the spline shaft.

[0011] A further preferred technical solution of the present invention is: a fourth bearing is provided between the end of the spline shaft away from the rocker bearing and the casing, the fourth bearing is fixedly installed in the casing, one end of the spline shaft is inserted into the center of the fourth bearing and connected to the fourth bearing, and the fourth bearing supports the end of the spline shaft.

[0012] A further preferred technical solution of the present invention is: a transmission tooth for transmitting rotational power to the rotating sleeve is fixed on the spline shaft, a chisel locking plate is fixed in the casing, an internal tooth hole matching the transmission tooth is opened on the chisel locking plate, the spline shaft passes through the internal tooth hole, and the spline shaft can move to a fourth position along the axial direction. When the spline shaft moves to the fourth position, the second end of the small gear shaft is only connected to the rocker bearing for transmission, and the transmission tooth moves into the internal tooth hole and engages with the internal tooth hole, and the chisel locking plate locks the rotation of the spline shaft.

[0013] A further preferred technical solution of the present invention is: the motor shaft of the motor and the intermediate sleeve are vertically changed in direction, the casing includes an outer shell, the outer shell includes a first outer shell, a second outer shell and a holding part, the first outer shell and the second outer shell are connected in an "L" shape, the holding part is connected to the rear of the first outer shell and the second outer shell, the motor is installed in the second outer shell, and the motion conversion mechanism, the impact mechanism and the rotating sleeve are installed in the first outer shell.

[0014] A further preferred technical solution of the present invention is: the casing further includes a fixing frame fixed in the outer shell, and the intermediate shaft sleeve, the pinion shaft, the rocker bearing and the motor are all mounted on the fixing frame.

[0015] A further preferred technical solution of the present invention is: a driving helical gear is fixed on the motor shaft of the motor, a driven helical gear meshing with the driving helical gear is fixed on the intermediate sleeve, the fixed frame includes a main frame body and a rear cover connected to the rear side of the main frame body, the rear cover and the main frame body are enclosed to form a receiving cavity for accommodating the driven helical gear, the driven helical gear is placed in the receiving cavity, the motor is fixed to the bottom of the main frame body, and the main frame body is provided with a through hole connecting the bottom of the main frame body and the receiving cavity.

[0016] A further preferred technical solution of the present invention is: an open groove opening downward is provided at the bottom of the main frame, the through hole is provided at the bottom of the open groove, the active helical gear is inserted into the open groove and engages with the driven helical gear, a fifth bearing is installed in the open groove, and the fifth bearing is sleeved on the motor shaft for supporting the motor shaft.

[0017] A further preferred technical solution of the present invention is as follows: the intermediate sleeve is a hollow sleeve body, the first end of the pinion shaft is inserted into the intermediate sleeve, the inner wall of the intermediate sleeve and the first end of the pinion shaft are respectively provided with a first tooth groove and a first meshing tooth that match each other, the elastic member is a spring located in the intermediate sleeve and supported between the first end of the pinion shaft and the intermediate sleeve, the central hole includes two channels with different inner diameters, the inner diameter of the first channel close to the intermediate sleeve is larger than that of the second channel, an annular step is provided between the first channel and the second channel, the annular step is provided with a second tooth groove that communicates with the inner wall of the second channel, the outer wall of the second end of the pinion shaft is provided with a second meshing tooth that matches the second tooth groove, the spring pushes the pinion shaft toward the spline shaft so that the second meshing tooth on the second end of the pinion shaft is inserted into the second tooth groove, the outer wall of the pinion shaft is provided with an annular support portion that matches the shape of the first channel, the end surface of the second end of the pinion shaft is provided with a spline groove for inserting one end of the spline shaft, and a spline that matches the spline groove is provided on one end of the spline shaft.

[0018] Compared with the prior art, the advantages of the present invention are that the transmission assembly includes a small gear shaft and an intermediate shaft sleeve with axial limitation, the intermediate shaft sleeve is meshed with the motor shaft of the motor and is driven to rotate by the motor shaft, the small gear shaft is arranged between the intermediate shaft sleeve and the rocker bearing and the spline shaft for transmission, the first end of the small gear shaft is axially movable and plugged into the intermediate shaft sleeve and the relative rotation of the two is restricted, an elastic member is provided between the small gear shaft and the intermediate shaft sleeve, the elastic member drives the small gear shaft to move toward one side of the spline shaft along the axial direction, and inserts the second end of the small gear shaft into the center hole of the rocker bearing, and when the spline shaft moves, it can push the small gear shaft to move along the axial direction The intermediate sleeve moves on one side, and the small gear shaft moves to the left or right, and then the second end is connected to the spline shaft and / or rocker bearing. This patent is responsible for the intermediate sleeve connected to the motor shaft and the small gear shaft used for transmission. The intermediate sleeve is rotatably installed in the casing and the axial movement is restricted, while the small gear shaft can move along the axial direction relative to the intermediate sleeve. When the spline shaft moves along the axial direction to switch the function of the electric hammer, only the small gear shaft will move back and forth to switch the transmission connection with the spline shaft and / or rocker bearing. The intermediate sleeve will not move, thereby ensuring the stability of the meshing connection between the intermediate sleeve and the motor shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be described in further detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and should not be construed as limiting the scope of the present invention. Furthermore, unless otherwise specified, the drawings are merely schematic representations of the composition or structure of the depicted objects and may contain exaggerated representations. Furthermore, the drawings are not necessarily drawn to scale.

[0020] Figure 1 It is the overall structure diagram of the electric hammer;

[0021] Figure 2 It is a cross-sectional diagram of an electric hammer;

[0022] Figure 3 Schematic diagram of the local structure of the electric hammer Figure 1 ;

[0023] Figure 4 This is a schematic diagram of the adjustment knob structure;

[0024] Figure 5 Schematic diagram of the local structure of the electric hammer Figure 2 ;

[0025] Figure 6 It is a cross-sectional schematic diagram when the spline shaft moves to the first position;

[0026] Figure 7 is a cross-sectional schematic diagram when the spline shaft moves to the second position;

[0027] Figure 8It is a cross-sectional schematic diagram when the spline shaft moves to the third position;

[0028] Figure 9 It is a cross-sectional schematic diagram when the spline shaft moves to the fourth position.

[0029] In the figure: 1. housing; 2. adjusting knob; 3. impact mechanism; 4. rotating sleeve; 5. motion conversion mechanism; 6. first housing; 7. second housing; 8. motor; 9. grip; 10. main frame; 11. rear cover; 12. receiving gear; 13. spline shaft; 14. chisel locking plate; 15. internal tooth hole; 16. transmission gear; 17. receiving member; 18. driven push rod; 19. shifting rod; 20. fixing frame; 21. housing; 22. striker rod; 23. striker; 24. piston; 25. intermediate sleeve; 26. retaining spring; 27. spring; 28. driven helical gear; 29. ​​pinion shaft; 30. rocker bearing; 31. center hole; 3 2. Active helical gear; 33. Motor shaft; 34. Fourth bearing; 35. Bearing slot three; 36. Third bearing; 37. Accommodation chamber; 38. Partition; 39. Intermediate support member; 40. Fifth bearing; 41. Opening slot; 42. Spline; 43. Spline slot; 44. Second tooth slot; 45. Second meshing tooth; 46. Annular support portion; 47. Second channel; 48. First meshing tooth; 49. First tooth slot; 50. Second bearing; 51. First channel; 52. Step one; 53. Bearing slot two; 54. Stop portion; 55. First bearing; 56. Bearing slot one; 57. Shaft hole one; 58. Mounting slot; 59. Shaft hole two. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely illustrative and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0031] It should be noted that like reference numerals denote like items in the following drawings, and thus, once an item is defined in one drawing, it may not be further defined or explained in subsequent drawings.

[0032] Figures 1-9 As shown, a multi-speed adjustable electric hammer with a stable structure includes a casing 1, in which a motor 8, a motion conversion mechanism 5, an impact mechanism 3 and a rotating sleeve 4 for connecting a working head are arranged. One end of the working head is assembled in the rotating sleeve 4. The motion conversion mechanism 5 is connected to the motor 8 and transmits the output power of the motor 8 to the impact mechanism 3 and the rotating sleeve 4. The impact mechanism 3 is used to drive the working head to reciprocate along the axis direction of the rotating sleeve 4, and the rotating sleeve 4 is used to drive the working head to rotate.

[0033] Figure 9As shown, the structures of the impact mechanism 3 and the rotary sleeve 4 and the way of driving the working head are the same as those of the existing electric hammer. The structure of the connection between the working head and the rotary sleeve 4 is the same as that of the existing electric hammer. Reference can be made to the impact shaft assembly in patent CN100513090C, the impact shaft assembly in patent CN1899772A, and the output shaft and impact mechanism in patent CN211729047U.

[0034] Figure 9 As shown, the motion conversion mechanism 5 includes a spline shaft 13 for driving the rotating sleeve 4 to rotate, a rocker bearing 30 and a transmission assembly for driving the impact mechanism 3 to reciprocate and impact. The rocker bearing 30 is located between the spline shaft 13 and the transmission assembly and has a center hole 31. The spline shaft 13 is rotatably installed in the casing 1. One end of the spline shaft 13 is inserted into the center hole 31 of the rocker bearing 30 and can switch and move between a first position, a second position and a third position along the axial direction. A driver for driving the spline shaft 13 to move is provided on the casing 1.

[0035] The spline shaft 13 is engaged with the rotating sleeve 4 for transmission. A transmission tooth 16 for transmitting rotational power to the rotating sleeve 4 is fixed on the spline shaft 13. The rotating sleeve 4 is connected with a receiving tooth 12 engaged with the transmission tooth 16. The receiving tooth 12 and the rotating sleeve 4 are restricted in relative rotation. When the spline shaft 13 rotates, the spline shaft 13 drives the rotating sleeve 4 to rotate through the transmission tooth 16.

[0036] The impact mechanism 3 includes a piston 24 connected to the rocker bearing 30 and receiving power from the rocker bearing 30, a hammer 23 cooperating with the piston 24, and a striker rod 22 cooperating with the hammer 23. The piston 24, the hammer 23 and the striker rod 22 can all be movably installed in the rotating sleeve 4. The rocker bearing 30 can drive the piston 24 to move back and forth in the rotating sleeve 4 along the axial direction of the rotating sleeve 4. The piston 24 drives the working head to reciprocate and impact by pushing the hammer 23 to hit the striker rod 22.

[0037] The axial directions of the spline shaft 13 and the intermediate sleeve 25 are parallel to the axial direction of the rotating sleeve 4 .

[0038] Figure 3 、 Figure 4 As shown, the driver includes an adjusting knob 2 rotatably mounted on the housing 1, a shifting rod 19 eccentric to the rotation center is fixed on the adjusting knob 2, a shifting member 17 is fixedly mounted on the spline shaft 13, two spaced apart driven push rods 18 are fixed on the shifting member 17, the shifting rod 19 is inserted between the two driven push rods 18, and when the adjusting knob 2 is manually rotated, the shifting rod 19 rotates eccentrically around the rotation center and can push the driven push rod 18 to move the spline shaft 13 to the left or right along the axial direction, thereby switching the spline shaft 13 between the first position, the second position and the third position.

[0039] Figure 2As shown, the transmission assembly includes a pinion shaft 29 and an intermediate shaft sleeve 25 with an axial limit, the intermediate shaft sleeve 25 is rotatably installed in the housing 1, the intermediate shaft sleeve 25 is engaged with the motor shaft 33 of the motor 8 and is driven to rotate by the motor shaft 33, the pinion shaft 29 is provided between the intermediate shaft sleeve 25 and the rocker bearing 30 and the spline shaft 13 for transmission, the right end of the pinion shaft 29 is the first end, the left end of the pinion shaft 29 is the second end, the intermediate shaft sleeve 25 is located on the right side of the pinion shaft 29, the spline shaft 13 is located on the left side of the pinion shaft 29, and the pinion shaft 29 is provided between the intermediate shaft sleeve 25 and the rocker bearing 30 and the spline shaft 13. The first end of the pinion shaft 29 is axially movable and plugged into the intermediate sleeve 25, and the relative rotation of the two is restricted. An elastic member is provided between the pinion shaft 29 and the intermediate sleeve 25. The elastic member drives the pinion shaft 29 to move along the axial direction toward the side of the spline shaft 13, and makes the second end of the pinion shaft 29 inserted into the center hole 31 of the rocker bearing 30. When the spline shaft 13 moves, it can push the pinion shaft 29 to move along the axial direction toward the side of the intermediate sleeve 25. After the pinion shaft 29 moves to the left or right, the second end is transmission connected with the spline shaft 13 and / or the rocker bearing 30.

[0040] Specifically, the intermediate sleeve 25 is a hollow sleeve body, and the first end of the pinion shaft 29 is inserted into the intermediate sleeve 25. The inner wall of the intermediate sleeve 25 and the first end of the pinion shaft 29 are respectively provided with a matching first tooth groove 49 and a first meshing tooth 48. The first tooth groove 49 meshes with the first meshing tooth 48 to limit the relative rotation of the intermediate sleeve 25 and the pinion shaft 29, so that the intermediate sleeve 25 can drive the pinion shaft 29 to rotate. The elastic member is a spring 27 located in the intermediate sleeve 25 and supported between the first end of the pinion shaft 29 and the intermediate sleeve 25. The center hole 31 includes two sections of channels with different inner diameters. The inner diameter of the first channel 51 close to the side of the intermediate sleeve 25 is larger than the inner diameter of the second channel 47. An annular step transition is provided between the first channel 51 and the second channel 47. The annular step is provided with a second tooth groove 44 communicating with the inner wall of the second channel 47. The outer wall of the second end of the pinion shaft 29 is provided with a second tooth groove 44 that cooperates with the second tooth groove 44 The spring 27 pushes the pinion shaft 29 to move toward the side of the spline shaft 13 and enables the second meshing tooth 45 on the second end of the pinion shaft 29 to be inserted into the second tooth groove 44, so that the pinion shaft 29 is connected to the rocker bearing 30 and can drive the rocker bearing 30 to swing back and forth. The outer wall of the pinion shaft 29 is provided with an annular support portion 46 that is adapted to the shape of the first channel 51. The end surface of the second end of the pinion shaft 29 is provided with a support for the spline shaft 13. A spline groove 43 is inserted into one end of the spline shaft 13, and a spline 42 is provided on one end portion of the spline shaft 13 to match the spline groove 43. The spline shaft 13 can move to the right so that the spline 42 at the right end of the spline shaft 13 is inserted into the spline groove 43, so that the small gear shaft 29 can drive the spline shaft 13 to rotate, and the spline shaft 13 can push the small gear shaft 29 to move to the right when continuing to move to the right, so that the second meshing tooth 45 on the second end of the small gear shaft 29 disengages from the second tooth groove 44.

[0041] The annular support portion 46 is used to maintain the stability of the pinion shaft 29 in its left-right movement within the center hole 31 .

[0042] A stopper 54 is provided in the intermediate sleeve 25 for limiting the maximum insertion distance of the pinion shaft 29. The stopper 54 can prevent the pinion shaft 29 from moving too much to the right and escaping from the center hole 31, thereby ensuring its stability.

[0043] A retaining spring 26 is fixed in the intermediate sleeve 25 , and one end of a spring 27 presses against the retaining spring 26 .

[0044] Figure 6 As shown, when in use, when the spline shaft 13 moves to the right to the first position, the right end of the spline shaft 13 is inserted into the spline groove 43 on the second end of the small gear shaft 29, so that the spline 42 engages with the spline groove 43. At the same time, the spline shaft 13 pushes the small gear shaft 29 to move to the right, so that the second meshing tooth 45 on the second end of the small gear shaft 29 disengages from the second tooth groove 44. The second end of the small gear shaft 29 is only connected to the spline shaft 13 for transmission. When the motor 8 is started, the intermediate sleeve 25 drives the small gear shaft 29 to rotate. When the small gear shaft 29 rotates, it drives the spline shaft 13 to rotate. The spline shaft 13 then drives the rotating sleeve 4 to rotate, and the rotating sleeve 4 drives the working head assembled in the rotating sleeve 4 to rotate. Since the second meshing tooth 45 disengages from the second tooth groove 44, the rotation of the small gear shaft 29 will not drive the rocker bearing 30 to swing back and forth. At this time, the working head only outputs rotational power to the outside, and the electric hammer is in gear shifting.

[0045] Figure 7 As shown, when the spline shaft 13 moves leftward from the first position to the second position, the pinion shaft 29 is pushed by the spring 27 to move leftward along with the spline shaft 13, so that the second meshing tooth 45 on the second end of the pinion shaft 29 is inserted into the second tooth groove 44 inside the rocker bearing 30 and meshes with the second tooth groove 44. Since the pinion shaft 29 moves leftward along with the spline shaft 13, the spline 42 at the right end of the spline shaft 13 remains in meshing with the spline groove 43. The second end of the pinion shaft 29 is simultaneously connected to the spline shaft 13 and the rocker bearing 30. When the motor 8 is started, the intermediate sleeve 25 drives the small gear shaft 29 to rotate. When the small gear shaft 29 rotates, it drives the spline shaft 13 to rotate, and at the same time drives the rocker bearing 30 to swing back and forth. The spline shaft 13 rotates to drive the rotating sleeve 4 to rotate. The rotating sleeve 4 rotates and can drive the working head to rotate. The rocker bearing 30 swings back and forth to drive the impact mechanism 3 to move back and forth. The reciprocating impact motion of the impact mechanism 3 hits the working head, causing the working head to achieve reciprocating impact motion. At this time, the working head simultaneously outputs rotation and reciprocating impact power to the outside, and the electric hammer is in the hammer drill gear.

[0046] Figure 8As shown, when the spline shaft 13 moves from the second position to the third position to the left, the second meshing tooth 45 on the second end of the pinion shaft 29 presses against the inner wall of the second tooth groove 44 and does not continue to move to the left with the spline shaft 13. The pinion shaft 29 maintains a transmission connection with the rocker bearing 30. Since the pinion shaft 29 is stationary and the spline shaft 13 moves to the left, the spline 42 on the right end of the spline shaft 13 is disengaged from the spline groove 43, and the spline shaft 13 and the pinion shaft 29 can rotate relative to each other. When the motor 8 is started, the intermediate sleeve 25 drives the pinion shaft 29 to rotate. When the pinion shaft 29 rotates, it drives the rocker bearing 30 to swing back and forth, and does not drive the spline shaft 13 to rotate. The rocker bearing 30 swings back and forth to drive the impact mechanism 3 to perform reciprocating impact motion, and the reciprocating motion of the impact mechanism 3 hits the working head, so that the working head realizes reciprocating impact motion. At this time, the working head only outputs reciprocating impact power to the outside, and the electric hammer is an adjustable gear for chiseling. Since the spline shaft 13 is disengaged from the pinion shaft 29 , the user can adjust the angle of the working head by rotating the working head externally.

[0047] This patent is responsible for the intermediate sleeve 25 connected to the motor shaft 33 and the small gear shaft 29 used for transmission are two parts. The intermediate sleeve 25 can be optionally installed in the casing 1 and its axial movement is restricted, while the small gear shaft 29 can move along the axial direction relative to the intermediate sleeve 25. When the spline shaft 13 moves along the axial direction to switch the function of the electric hammer, only the small gear shaft 29 will move back and forth to switch the transmission connection with the spline shaft 13 and / or the rocker bearing 30, and the intermediate sleeve 25 will not move, thereby ensuring the stability of the meshing connection between the intermediate sleeve 25 and the motor shaft 33.

[0048] Figure 2 As shown, in addition, the motor shaft 33 of the motor 8 and the intermediate shaft sleeve 25 are vertically changed in direction for transmission, the casing 1 includes an outer shell 21 and a fixing frame 20 fixed in the outer shell 21, the outer shell 21 includes a first outer shell 6, a second outer shell 7 and a holding portion 9, the first outer shell 6 and the second outer shell 7 are connected in an "L" shape, the holding portion 9 is connected to the rear of the first outer shell 6 and the second outer shell 7, the motor 8 is installed in the second outer shell 7, the motion conversion mechanism 5, the impact mechanism 3 and the rotating sleeve 4 are all installed in the first outer shell 6, the motor shaft 33 of the motor 8 and the intermediate shaft sleeve 25 are vertically changed in direction for transmission, and the motor 8 is installed in the second outer shell 7, which can shorten the length required for the first outer shell 6, thereby making the electric hammer structure more compact.

[0049] The above-mentioned intermediate shaft sleeve 25, small gear shaft 29, rocker arm bearing 30 and motor 8 are all installed on the fixed frame 20. The intermediate shaft sleeve 25, small gear shaft 29, rocker arm bearing 30 and motor 8 are connected to the fixed frame 20 as a whole, which facilitates the installation of each component into the housing 21.

[0050] Figure 9As shown, specifically, a driving helical gear 32 is fixed to the motor shaft 33 of the motor 8, and a driven helical gear 28 meshing with the driving helical gear 32 is fixed to the intermediate sleeve 25. The fixed frame 20 includes a main frame body 10 and a rear cover 11 connected to the rear side of the main frame body 10. The rear cover 11 and the main frame body 10 are enclosed to form an accommodating cavity 37 for accommodating the driven helical gear 28. The driven helical gear 28 is placed in the accommodating cavity 37. The motor 8 is fixed to the bottom of the main frame body 10. The main frame body 10 is provided with a through hole 1 connecting the bottom of the main frame body 10 and the accommodating cavity 37.

[0051] The intermediate sleeve 25 is rotatably mounted in the accommodating chamber 37. Specifically, the main frame 10 is provided with an axial hole 1 57 connecting the front and rear sides, and the rear cover 11 is provided with an axial hole 2 59 connecting the front and rear sides. The two ends of the intermediate sleeve 25 are respectively rotatably inserted in the axial hole 1 57 and the axial hole 2 59, and the driven helical gear 28 on the intermediate sleeve 25 is located in the accommodating chamber 37.

[0052] A mounting groove 58 is provided on the front side of the main frame 10. The mounting groove 58 is located in front of the shaft hole 1 57 and is connected to the shaft hole 1 57. One end of the rocker arm bearing 30 is inserted into the mounting groove 58 and is clamped in the mounting groove 58 by the retaining spring 26, so that the rocker arm bearing 30 is fixedly mounted on the main frame 10. The first end and the second end of the pinion shaft 29 are respectively inserted into the intermediate sleeve 25 and the center hole 31.

[0053] An open slot 41 opening downward is provided at the bottom of the main frame 10, and a through hole is provided at the bottom of the open slot 41. The active helical gear 32 is inserted into the open slot 41 and engages with the driven helical gear 28. A fifth bearing 40 is installed in the open slot 41, and the fifth bearing 40 is sleeved on the motor shaft 33 to support the motor shaft 33.

[0054] Specifically, a partition 38 is installed at the notch of the opening groove 41. The partition 38 is fixed to the bottom of the main frame 10 by screws. A through hole 2 is provided in the center of the partition 38 for the motor shaft 33 to pass through. An intermediate support member 39 is provided between the fifth bearing 40 and the partition 38. The partition 38 presses the fifth bearing 40 against the inner wall of the opening groove 41 through the intermediate support member 39 to limit the movement of the fifth bearing 40. A sleeve portion is fixed to the bottom of the active helical gear 32. The active helical gear 32 is tightly fitted on the motor shaft 33 and fixed to the motor shaft 33. The fifth bearing 40 is sleeved on the sleeve portion to support the active helical gear 32 and the motor shaft 33, preventing the motor shaft 33 and the active helical gear 32 from swinging during rotation, thereby making the meshing between the active helical gear 32 and the driven helical gear 28 more stable. The preferred fifth bearing 40 is a deep groove ball bearing.

[0055] In addition, a first bearing 55 and a second bearing 50 are respectively provided between the front and rear ends of the intermediate sleeve 25 and the casing 1 . The first bearing 55 and the second bearing 50 are sleeved on the front and rear ends of the intermediate sleeve 25 to support the intermediate sleeve 25 .

[0056] Specifically, the rear side of the main frame 10 is provided with a bearing groove 1 56 located on the rear side of the shaft hole 1 57, and the bearing groove 1 56 is connected to the shaft hole 1 57, and the first bearing 55 is fixedly installed in the bearing groove 1 56. The front side of the rear cover 11 is provided with a bearing groove 2 53 located in front of the shaft hole 2 59, and the bearing groove 2 53 is connected to the shaft hole 2 59, and the second bearing 50 is installed in the bearing groove 2 53, and a retaining spring 26 is clamped on the inner wall of the bearing groove 2 53. The retaining spring 26 presses the second bearing 50 tightly in the bearing groove 2 53 to limit movement. The first bearing 55 and the second bearing 50 are respectively sleeved on the front and rear sides of the intermediate sleeve 25. In addition, a step 1 52 is provided on the outer wall of the intermediate sleeve 25, which is located on the left side of the second bearing 50, and a retaining spring 26 is clamped on the outer wall of the intermediate sleeve 25, which is located on the right side of the second bearing 50. The retaining spring 26 and the step 1 52 limit the relative axial movement of the second bearing 50 and the intermediate sleeve 25, thereby limiting the axial movement of the intermediate sleeve 25. Preferably, the first bearing 55 is an oil-containing bearing, and the second bearing 50 is a deep groove ball bearing.

[0057] There are two bearing fixed positions at both ends of the intermediate sleeve 25. When the function is switched, only the small gear shaft 29 will move back and forth, and the intermediate sleeve 25 and the driven helical gear 28 will not move, ensuring the stability of the engagement between the driven helical gear 28 and the driving helical gear 32. The first bearing 55 and the second bearing 50 can also ensure the coaxiality of the rotation of the intermediate sleeve 25 to prevent yaw.

[0058] Furthermore, a third bearing 36 is fixedly mounted in the center hole 31 of the rocker bearing 30. One end of the spline shaft 13 is inserted into the center hole 31 and passes through the center of the third bearing 36, supporting one end of the spline shaft 13. The installation of the third bearing 36 in the rocker bearing 30, since the rocker bearing 30 is fixedly mounted on the main frame 10, ensures the stability of the third bearing 36. This makes the spline shaft 13 more stable when receiving power transmitted by the pinion shaft 29 and less prone to misalignment. Preferably, the third bearing 36 is a needle roller bearing.

[0059] In addition, a fourth bearing 34 is provided between the end of the spline shaft 13 away from the rocker bearing 30 and the housing 1. The fourth bearing 34 is fixedly mounted within the housing 1. One end of the spline shaft 13 is inserted into the center of the fourth bearing 34 and connected thereto. The fourth bearing 34 supports the end of the spline shaft 13. Specifically, a third bearing slot 35 is provided within the housing 1, and the fourth bearing 34 is fixedly mounted therein. Preferably, the fourth bearing 34 is a needle roller bearing.

[0060] The front and rear ends of the spline shaft 13 are fixed with bearings to ensure the meshing stability of the spline shaft 13 and other teeth, and to ensure the concentricity of the spline shaft 13.

[0061] Figure 9As shown, in addition, a chisel locking plate 14 is fixed in the housing 1, and an internal tooth hole 15 is opened on the chisel locking plate 14 to match the transmission tooth 16 on the above-mentioned spline shaft 13. The spline shaft 13 passes through the internal tooth hole 15. The spline shaft 13 can also move to the fourth position along the axial direction. When the spline shaft 13 moves leftward from the third position to the fourth position, the second end of the small gear shaft 29 is only connected to the rocker bearing 30 for transmission. The second meshing tooth 45 on the second end of the small gear shaft 29 continues to maintain a state of meshing with the second tooth groove 44. Since the small gear shaft 29 does not move, the spline shaft 13 moves leftward. The chisel locking plate 14 locks the rotation of the spline shaft 13. When the motor 8 is started, the intermediate sleeve 25 drives the pinion shaft 29 to rotate. The rotation of the pinion shaft 29 drives the rocker bearing 30 to swing back and forth without causing the spline shaft 13 to rotate. The back and forth swing of the rocker bearing 30 drives the impact mechanism 3 to reciprocate, and the reciprocating motion of the impact mechanism 3 strikes the working head, causing the working head to achieve reciprocating impact motion. At this time, the working head only outputs reciprocating impact power, and the electric hammer is in the chiseling mode. Because the spline shaft 13 is locked from rotation by the chisel locking plate 14, the working head only outputs impact power and cannot be rotated externally.

[0062] When the spline shaft 13 switches and moves between the first position, the second position, the third position and the fourth position, the spline shaft 13 is always engaged with the rotating sleeve 4 for transmission, and the pinion shaft 29 is always engaged with the intermediate sleeve 25.

[0063] In addition, the other structures of the electric hammer are the same as those of the existing electric hammer.

[0064] The above describes the structurally stable, multi-speed adjustable electric hammer provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is intended only to facilitate understanding of the present invention and its core concepts. It should be noted that those skilled in the art may, without departing from the principles of the present invention, make various improvements and modifications to the present invention, and such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A multi-speed adjustable electric hammer with a stable structure, comprising a casing, a motor, a motion conversion mechanism, an impact mechanism and a rotary sleeve for connecting a working head, the motion conversion mechanism being connected to the motor and transmitting the output power of the motor to the impact mechanism and the rotary sleeve, the impact mechanism being used to drive the working head to reciprocate along the axis direction of the rotary sleeve, the rotary sleeve being used to drive the working head to rotate, the motion conversion mechanism comprising a spline shaft for driving the rotary sleeve to rotate, a rocker bearing and a transmission assembly for driving the impact mechanism to reciprocate and impact, the rocker bearing being located between the spline shaft and the transmission assembly and having a center hole, the spline shaft being rotatably mounted in the casing, one end of the spline shaft being inserted into the center hole of the rocker bearing and being able to switch and move along the axis direction between a first position, a second position and a third position, a driver for driving the spline shaft to move being provided on the casing, characterized in that, The transmission mechanism that this first pinion shaft is used for isolating is fixedly mounted on the support frame, and this second pinion shaft is connected with the support frame of this support frame by the elastic member that is arranged on this support frame, and this elastic member is arranged between this support frame and this support frame. The first end of the pinion shaft is inserted into the middle sleeve, and the inner wall of the middle sleeve and the first end of the pinion shaft are respectively provided with a matching first tooth groove and a first meshing tooth. The elastic member is a spring located in the middle sleeve and supported between the first end of the pinion shaft and the middle sleeve. The center hole includes two sections of channels with different inner diameters, the inner diameter of the first channel close to the middle sleeve is larger than the second channel, and an annular step transition is provided between the first channel and the second channel. The annular step is provided with a second tooth groove connected to the inner wall of the second channel, and the outer wall of the second pinion shaft is provided with a second meshing tooth matching the second tooth groove. The spring pushes the pinion shaft to move to one side of the spline shaft so that the second meshing tooth on the second end of the pinion shaft is inserted into the second tooth groove. The outer wall of the pinion shaft is provided with an annular support portion adapted to the shape of the first channel, and a spline groove for inserting one end of the spline shaft is opened on the end surface of the second end of the pinion shaft, and a spline matching the spline groove is provided at one end of the spline shaft. When the spline shaft moves to the first position, the second end of the pinion shaft is only connected to the spline shaft, and the working head can only output rotational power to the outside. When the spline shaft moves to the second position, the second end of the pinion shaft is simultaneously connected to the spline shaft and the rocker bearing, and the working head can simultaneously output rotational and reciprocating impact power to the outside. When the spline shaft moves to the third position, the second end of the pinion shaft is only connected to the rocker bearing, and the working head can only output impact power to the outside.

2. The structurally stable multi-speed adjustable electric hammer according to claim 1, characterized in that: The rocker bearing is fixedly installed in the casing, and a third bearing is fixedly installed in the center hole of the rocker bearing. One end of the spline shaft is inserted into the center hole and passes through the center of the third bearing. The third bearing is used to support one end of the spline shaft.

3. The structurally stable multi-speed adjustable electric hammer according to claim 2, characterized in that: A fourth bearing is provided between the end of the spline shaft away from the rocker bearing and the casing. The fourth bearing is fixedly installed in the casing. One end of the spline shaft is inserted into the center of the fourth bearing and connected to the fourth bearing. The fourth bearing supports the end of the spline shaft.

4. The structurally stable multi-speed adjustable electric hammer according to claim 1, characterized in that: The spline shaft is fixed with a transmission tooth for transmitting rotational power to the rotating sleeve, and the housing is fixed with a chisel locking plate, which is provided with an internal tooth hole that matches the transmission tooth. The spline shaft passes through the internal tooth hole. The spline shaft can move to a fourth position along the axial direction. When the spline shaft moves to the fourth position, the second end of the small gear shaft is only connected to the rocker bearing for transmission, and the transmission tooth moves into the internal tooth hole and engages with the internal tooth hole. The chisel locking plate locks the rotation of the spline shaft.

5. The structurally stable multi-speed adjustable electric hammer according to claim 1, characterized in that: The motor shaft of the motor and the intermediate sleeve are vertically changed in direction. The casing includes an outer shell, and the outer shell includes a first outer shell, a second outer shell and a holding part. The first outer shell and the second outer shell are connected in an "L" shape. The holding part is connected to the rear of the first outer shell and the second outer shell. The motor is installed in the second outer shell, and the motion conversion mechanism, the impact mechanism and the rotating sleeve are installed in the first outer shell.

6. The structurally stable multi-speed adjustable electric hammer according to claim 5, characterized in that: The casing further comprises a fixing frame fixed in the outer shell, and the intermediate shaft sleeve, the pinion shaft, the rocker bearing and the motor are all mounted on the fixing frame.

7. The structurally stable multi-speed adjustable electric hammer according to claim 6, characterized in that: A driving helical gear is fixed on the motor shaft of the motor, and a driven helical gear meshing with the driving helical gear is fixed on the intermediate sleeve. The fixed frame includes a main frame body and a rear cover connected to the rear side of the main frame body. The rear cover and the main frame body are enclosed to form a receiving cavity for accommodating the driven helical gear. The driven helical gear is placed in the receiving cavity. The motor is fixed to the bottom of the main frame body. The main frame body is provided with a through hole connecting the bottom of the main frame body and the receiving cavity.

8. The structurally stable multi-speed adjustable electric hammer according to claim 7, characterized in that: An opening groove opening downward is provided at the bottom of the main frame, the through hole is provided at the bottom of the opening groove, the active helical gear is inserted into the opening groove and engages with the driven helical gear, a fifth bearing is installed in the opening groove, and the fifth bearing is sleeved on the motor shaft for supporting the motor shaft.

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