Tool fixture and electric hammer

Abstract

A tool fixture (30) and an electric hammer (100). The tool fixture (30) is provided with a step portion (314) on a fixture base (31) thereof; a first locking mechanism and a second locking mechanism are respectively located on two sides of the step portion (314); a support ring (38) which does not move axially relative to the fixture base (31) is provided in front of the step portion (314); a first spring (37) is fixedly provided at the step portion (314) and is configured to apply an elastic locking force to the first locking mechanism; a second spring (36) is fixedly provided on the support ring (38) and is configured to apply an elastic locking force to the second locking mechanism; and in the axial direction of the fixture base (31), the first spring (37) and the second spring (36) at least partially overlap, thereby reducing the axial size of the tool fixture. Moreover, a third spring (320) is provided, which abuts between the support ring (38) and a first sleeve (35) of the first locking mechanism, so as to provide a support force for the first sleeve (35), thereby preventing the first sleeve (35) from moving downwards due to gravity during a slow vertical downward insertion of a drill bit, which otherwise causes a locking element to jam, hinders smooth insertion of the drill bit, affects the insertion and withdrawal comfort, and thus affects the user's operating experience.

Description

Tools, jigs and electric hammers Technical Field

[0001] This application relates to the field of power tools, and in particular to an electric hammer for impacting or rotating concrete, masonry and other structures, and a tool clamp for such an electric hammer. Background Technology

[0002] As a core adapter component for power tools such as electric hammers, the main function of tool clamps is to achieve a reliable connection with the output end of the electric hammer and to stably clamp the tool head (such as a drill bit).

[0003] In related technical solutions, this type of tool clamp typically employs a design with two springs arranged axially back and forth, providing the preload force for connecting the tool clamp to the output end of the electric hammer, and the clamping force for securing the tool head. However, this design significantly increases the axial dimension of the tool clamp, resulting in an unreasonable structural layout and consequently a poor user experience.

[0004] Therefore, it is indeed necessary to provide an improved power tool to overcome the shortcomings of the existing technology. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this application is to provide a tool clamp with a reasonable layout and high operating comfort, and an electric hammer equipped with the tool clamp.

[0006] This specification provides a tool clamp for selectively mounting a tool head on an electric hammer, the tool clamp comprising:

[0007] A clamp base having a stepped portion;

[0008] A first locking mechanism, at least partially located on one side of the stepped portion, is configured to selectively lock the tool head;

[0009] The first locking mechanism includes a first spring, which is fixedly disposed on the step portion and configured to apply an elastic force to the first locking mechanism to achieve locking;

[0010] The second locking mechanism, at least partially located on the other side of the step, is configured to be selectively locked to the electric hammer;

[0011] The second locking mechanism includes a second spring and a support ring, the support ring being at least partially located in front of the stepped portion and having no axial movement relative to the clamp base, the second spring being fixedly disposed on the support ring and configured to apply an elastic force to the second locking mechanism for locking.

[0012] Along the axial direction of the clamp base, the first spring and the second spring at least partially overlap, and when the first locking mechanism is driven to unlock the tool head, the second spring maintains its original pressure state.

[0013] This specification also provides an electric hammer, which includes a housing, a motor housed within the housing, a rotating shaft driven by the motor, and a tool clamp connected to the rotating shaft.

[0014] As can be seen from the above, the tool clamp and electric hammer provided in this specification have the following beneficial technical effects:

[0015] This invention provides a tool clamp with a stepped portion on its clamp base. A first locking mechanism and a second locking mechanism are respectively located on both sides of the stepped portion, and a support ring that does not move axially relative to the clamp base is provided in front of the stepped portion. A first spring of the first locking mechanism is fixedly disposed on the stepped portion and is configured to apply an elastic force to the first locking mechanism to achieve locking. A second spring of the second locking mechanism is fixedly disposed on the support ring and is configured to apply an elastic force to the second locking mechanism to achieve locking. Therefore, along the axial direction of the clamp base, the first spring and the second spring at least partially overlap, shortening the axial dimension of the tool clamp and optimizing the structural layout. Attached Figure Description

[0016] Figure 1 is a perspective view of the tool clamp of the preferred embodiment of the present invention mounted on an electric hammer;

[0017] Figure 2 is a half-sectional view of the tool fixture and electric hammer shown in Figure 1;

[0018] Figure 3 is a perspective view of the tool fixture shown in Figure 1;

[0019] Figure 4 is a half-sectional view of the tool fixture shown in Figure 3 taken from the first locking element;

[0020] Figure 5 is an exploded view of the tool fixture shown in Figure 3;

[0021] Figure 6 is a partial sectional view of the tool fixture shown in Figure 3;

[0022] Figures 7 to 9 are half-sectional views of the process of inserting a drill bit into the tool fixture shown in Figure 3;

[0023] Figure 10 is a half-sectional view of a second possible implementation in which the support ring has no axial movement relative to the clamp base;

[0024] Figure 11 is an exploded view of the slider, support ring and clamp base in the embodiment shown in Figure 10;

[0025] Figure 12 is a half-sectional view of a third possible implementation of the support ring without axial movement relative to the clamp base;

[0026] Figure 13 is an exploded view of the slider, support ring, and clamp base in the embodiment shown in Figure 12;

[0027] Meaning of reference numerals in the figure: Electric hammer 100; Housing 10; Shaft 11; Receiving groove 111; Motor 20; Motor shaft 21; Tool clamp 30; Clamp base 31, 31', 31″; Second cylindrical portion 311, 311', 311″; Second through hole 312, 312', 312″; First through hole 313, 313', 313″; Stepped portion 314, 314', 314″; First cylindrical portion 315; Third through hole 316; Protrusion 3111'; Connecting channel 3112″; Second locking element 32, 32', 32″; First locking element 33, 33', 33″; Second sleeve 34, 34', 34″; Locking ring 341; Notch 342; First sleeve 35, 35′, 35″; through groove 351; pressing ring 352; guide slope 3521; pressing surface 3522; receiving space 3523; extension 353; second spring 36, 36′, 36″; first spring 37, 37′, 37″; support ring 38, 38′, 38″; support claw 381; receiving groove 382; abutting part 383′; L-shaped groove 3831′; support part 384′; stop groove 385′, 385″; support arm 386″; hook part 3861″; stop ring 39; lug 391; sliding part 310, 310′, 310″; protrusion 3101′, 3101″; third spring 320; dust cover 330; protrusion 3301; gap 3302; Receiving cavity 340; Torque transmission element 350; O-ring 360; Transmission mechanism 40; First gear 41; Eccentric wheel 42; Eccentric pin 43; Second gear 44; Small bevel gear 45; Impact mechanism 50; Large bevel gear 51; Impact rod 52; Hammer 53; Piston 54; Connecting rod 55; Drill bit 200; Shank 201; Groove 2011 Detailed Implementation

[0028] The terminology used in this application is for the purpose of describing specific embodiments only and is not intended to limit the application. For example, terms such as "upper," "lower," "front," and "rear" that indicate orientation or positional relationship are based solely on the orientation or positional relationship shown in the accompanying drawings and are used only for the convenience of describing the application and simplifying the description, and are not intended to indicate or imply that the device / component referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the application.

[0029] The output end of an electric hammer typically has a detachable tool clamp for holding the tool head. This detachable clamp requires springs to provide two forces: a locking force to secure the clamp to the hammer's output end (this force needs to be substantial to ensure high reliability during operation); and a locking force to hold the tool head (this force needs to be moderate to accommodate frequent tool head changes). Therefore, the clamp usually has at least two springs to perform these functions. However, in some technical solutions, these two springs are arranged axially front-back, resulting in a superimposed axial dimension. This leads to a large overall clamp length and significant space requirements, making it difficult to meet the construction needs of confined spaces and other special scenarios.

[0030] In summary, the tool fixtures in the relevant technical solutions often suffer from poor user experience due to unreasonable structural design, and urgently need to be optimized and improved.

[0031] In view of the above-mentioned technical problems, this application provides a tool clamp and an electric hammer for drilling or chiseling on walls, cement floors and other surfaces. The invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0032] Please refer to Figures 1 to 9, which illustrate a preferred embodiment of the present invention, including a tool holder 30 and an electric hammer 100. The direction indicated by the arrow in Figure 4 is defined as the axial direction; the output direction of the electric hammer 100 is defined as forward; and the direction opposite to the output direction of the electric hammer 100 is defined as rearward. The electric hammer 100 includes a housing 10, a motor 20, a transmission mechanism 40, an impact mechanism 50, a tool holder 30 detachably connected to the front end of the housing 10, and a tool head 200 detachably mounted in the tool holder 30, all housed within the housing 10. In this embodiment, the tool head 200 can be a drill bit or a chisel, etc. After the electric hammer 100 is started, the motor 20 drives the tool head 200 within the tool holder 30 to rotate and output power via the transmission mechanism 40; simultaneously, the motor 20 drives the impact mechanism 50 to input impact power via the transmission mechanism 40, and the impact mechanism 50 drives the tool head 200 within the tool holder 30 to output impact power.

[0033] Please refer to Figures 1 and 2. The motor 20 includes a motor shaft 21 extending perpendicular to the output direction. The transmission mechanism 40 includes a first gear 41, an eccentric wheel 42, an eccentric pin 43, a second gear 44, and a small bevel gear 45. The impact mechanism 50 includes a rotating shaft 11, a large bevel gear 51 sleeved on the rotating shaft 11, and an impact rod 52, a hammer 53, a piston 54, and a connecting rod 55 arranged sequentially from front to back within the rotating shaft 11. The tool holder 30 is connected to the rotating shaft 11. The second gear 44 meshes with the first gear 41 on the left and right sides of the motor shaft 21, respectively. The second gear 44 is connected to the small bevel gear 45. The motor shaft 21 drives the small bevel gear 45 to rotate through the second gear 44. The small bevel gear 45 meshes with the large bevel gear 51 to drive the rotating shaft 11 to rotate. The rotating shaft 11 drives the tool head 200 in the tool holder 30 to rotate. The eccentric wheel 42 is connected to the first gear 41. The motor shaft 21 drives the eccentric wheel 42 to rotate through the first gear 41. The eccentric pin 43 is integrally set with the eccentric wheel 42. The rear end of the connecting rod 55 is sleeved on the eccentric pin 43, and the front end is pivotally connected to the piston 54. The eccentric wheel 42 drives the piston 54 to reciprocate through the connecting rod 55. When the piston 54 reciprocates, the compressed air drives the hammer 53 to strike the impact rod 52. After being impacted, the impact rod 52 strikes the tool head 200 in the output direction.

[0034] Please refer to Figures 4 to 6. The tool clamp 30 includes a clamp base 31, a first locking mechanism, and a second locking mechanism. The clamp base 31 has a receiving cavity 340 for receiving the tool head 200. The clamp base 31 includes a first cylindrical portion 315, a second cylindrical portion 311, and a stepped portion 314 located between the first cylindrical portion 315 and the second cylindrical portion 311. The first cylindrical portion 315 has a first through hole 313 and a third through hole 316 that penetrate from the outside to its inner wall in the radial direction. The second cylindrical portion 311 has a second through hole 312 that penetrates from the outside to its inner wall in the radial direction.

[0035] The first locking mechanism includes a first sleeve 35, a slider 310, a first spring 37, a first locking element 33, and a torque transmission element 350. The first locking element 33 is located in the first through hole 313 and is used to hold the handle 201 of the tool head 200 to prevent the tool head 200 from disengaging from the tool holder 30 in the longitudinal direction. The torque transmission element 350 is located in the third through hole 316 and is used to transmit torque. The first end of the first spring 37 abuts against the step portion 314, and the second end of the first spring 37 biases the slider 310 against the first sleeve 35 so that the first spring 37 applies an elastic force to the first locking element 33 through the first sleeve 35 to achieve locking, so that the first sleeve 35 radially limits the first locking element 33 to the locked position along the first through hole 313.

[0036] The second locking mechanism includes a second sleeve 34, a second spring 36, a support ring 38, and a second locking element 32. The second locking element 32 is located in the second through hole 312 and is used to engage the tool clamp 30 with the electric hammer 100. The support ring 38 is at least partially located in front of the step portion 314 and has no axial movement relative to the clamp base 31. In this embodiment, a stop ring 39 is also sleeved on the clamp base 31. The stop ring 39 is located in front of the support ring 38 and has no axial movement relative to the clamp base 31. The first sleeve 35 includes a plurality of axially extending through grooves 351 and a plurality of axially forward extending extension portions 353 inside. The stop ring 39 includes a plurality of outwardly extending lugs 391 on its outer periphery. The lugs 391 are located between every two extension portions 353. The end of the support ring 38 away from the first spring 36 has a plurality of axially extending support claws 381. The support claws 381 pass through the through grooves 351 and abut against the lugs 391. Specifically, a slot is provided at the front end of the clamp base 31. The slot is located at the front end of the stop ring 39 and a retaining spring is provided in the slot. The second spring 36 biases forward on the support ring 38, so that the support claw 381 of the support ring 38 abuts against the stop ring 39. The stop ring 39 cannot move forward due to the limitation of the front retaining spring, so that the support ring 38 has no axial movement relative to the clamp base 21.

[0037] The first end of the second spring 36 biases the second sleeve 34, and the second end of the second spring 36 biases the support ring 38, so that the second spring 36 applies an elastic force to the second locking element 32 through the second sleeve 34 to achieve locking, so that the second sleeve 34 radially limits the second locking element 32 to the locked position along the second through hole 312.

[0038] Along the axial direction of the clamp base 31, the first spring 37 and the second spring 36 at least partially overlap, which shortens the overall length of the tool clamp 30. Therefore, when the tool clamp 30 is mounted on the electric hammer 100, it is beneficial to the miniaturization of the whole machine and facilitates construction in confined spaces.

[0039] In one possible implementation, the first sleeve 35 has a pressing ring 352 fixed inside it, the pressing ring 352 having a pressing surface 3522 facing the first locking element 33. The sliding member 310 is held inside the pressing ring 352 by the biasing force of the first spring 37. The pressing surface 3522 presses the first locking element 33 through the first through hole 313, so that the first locking element 33 is in the locked position. Specifically, please refer to Figures 7 to 9 to see the process of inserting the tool head 200 into the tool holder 30. When the tool head 200 is inserted, the end of the tool head 200 pushes the first locking element 33. The tool head 200 moves backward and presses against the sliding member 310, thereby compressing the first spring 37. When the first locking element 33 disengages from the radial limit of the pressing ring 352, the first locking element 33 can move radially outward, and the tool head 200 can continue to be inserted backward. When the first locking element 33 passes the end of the tool head 200 and falls into the groove 2011 on the handle 201 of the tool head 200, the elastic force of the first spring 37 pushes the sliding member 310, thereby further pushing the first locking element 33 forward into the pressing ring 352, ensuring that the first locking element 33 is in the locked position, that is, the tool clamp 30 clamps the tool head 200.

[0040] The end of the pressing surface 3522 away from the sliding member 310 has a guide slope 3521. The inner wall of the first sleeve 35 facing the clamp base 31, together with the guide slope 3521 and the stop ring 39, forms a receiving space 3523. When the tool head 200 needs to be removed, the first sleeve 35 is slid backward. The first sleeve 35 moves towards the second sleeve 34 against the force of the first spring 37 through the sliding member 310. The first locking element 33 disengages from the radial limit of the pressing surface 3522 and can move into the receiving space. In space 3523, the first locking element 33 is in the released position, that is, the tool chuck 30 can release the tool head 200; the support ring 38 is not pushed to move axially during the entire travel of the first sleeve 35, that is, when the first locking mechanism is driven to unlock the tool head 200, the second spring 36 maintains its original pressure state. This avoids the need to overcome the forces of the first spring 37 and the second spring 36 when pulling the first sleeve 35 during the release of the tool head 200, which would affect the user's operating comfort.

[0041] Please refer to Figures 4 and 5. The second sleeve 34 has a locking ring 341 fixed inside it. The locking ring 341 surrounds the second locking element 32. The support ring 38 is provided with a receiving groove 381 facing the locking ring 341. The second spring 36 is supported between the receiving groove 382 and the locking ring 341. The locking ring 341 is subjected to the biasing force of the second spring 36, which pushes the second locking element 32 radially inward through the second through hole 312, so that the second locking element 32 is in the locked position. The end of the second sleeve 34 away from the first sleeve 35 has a notch 342 for the second locking element 32 to move radially outward. By sliding the second sleeve 35, the locking ring 341 moves against the force of the second spring 36 toward the first sleeve 35 to a position separated from the second locking element 32. The second locking element 32 can move radially into the notch 342, so that the second locking element 32 is in the released position.

[0042] An O-ring 360 is also fitted on the fixture base 31. The O-ring 360 is located at the rear end of the recess 342 and partially covers the opening at the rear end of the recess 342 to prevent the second locking element 32 from falling out of the opening at the rear end of the recess 342 after it moves into the recess 342.

[0043] Those skilled in the art will understand that the tool holder is equipped with a first sleeve for inserting and removing the drill bit. During the insertion of the tool bit, the first sleeve must always remain in the foremost position to avoid jamming with the locking element inside the tool holder, thereby preventing difficulty in inserting the tool bit. In some related technical solutions, the positioning of the sleeve usually relies on an interference fit with the front rubber dust cap. However, the reliability of this interference fit is easily affected by wear. Once the interference fit diminishes, when the tool bit is inserted vertically and slowly downwards, the sleeve will shift downwards due to gravity, causing the locking element to jam, ultimately preventing the tool bit from being inserted smoothly.

[0044] Please refer to Figures 4 and 5. In a tool holder provided by one or more optional embodiments of this specification, the first locking mechanism further includes a third spring 320. The first end of the third spring 320 biases against the support ring 38 and is at least partially sleeved on the outer periphery of the support claw 381 of the support ring 38. The second end of the third spring 320 biases against the first sleeve 35. During the insertion of the tool head 200, the third spring 320 can always provide support force to the first sleeve 35, keeping the first sleeve 35 at the front. This prevents the first sleeve 35 from falling towards the second sleeve 34 due to the loss of support from the first spring 37 when the electric hammer 100 is slowly inserted into the tool head 200 while it is placed vertically. This would cause the first locking element 33 to jam, resulting in the tool head 200 being unable to be inserted or being blocked during insertion, thus affecting the user's operating experience.

[0045] Along the axial direction of the clamp base 31, the support ring 38 and the slider 310 at least partially overlap, and the slider 310 is relatively movable within the inner ring of the support ring 38, which is beneficial for space compactness. At the same time, it can prevent the distance between the support ring 38 and the first sleeve 35 from being too short when the support ring 38 and the slider 310 are not overlapping. This would cause the third spring 320 to be completely compressed when the first sleeve 35 is moved backward during the operation of removing the tool head 200. The first sleeve 35 continues to press against the support ring 38 backward through the fully compressed third spring 320. At this time, the operator will clearly feel that the first sleeve 35 cannot be pushed forward, which makes it difficult to remove the tool head 200.

[0046] In one embodiment, the elastic coefficient of the first spring 37 is less than that of the second spring 36, meaning that the force pushing the first sleeve 35 backward is less than the force pushing the second sleeve 34 forward. This results in a greater locking force when the tool clamp 30 is connected to the rotating shaft 11 of the electric hammer 100, ensuring high reliability of the connection when the electric hammer 100 is working. At the same time, it provides a suitable force for clamping the tool head 200, ensuring high ease of operation and comfort during the high-frequency operation of changing the tool head 200. The elastic coefficient of the third spring 320 is less than that of the first spring 37, ensuring that the third spring 320 generates almost no additional resistance during the insertion and removal of the tool head 200, thus affecting the comfort of inserting and removing the tool head.

[0047] In one possible implementation, the spring constant of the first spring 37 is 1.44 N / mm, the spring constant of the second spring 36 is 2.5 N / mm, and the spring constant of the third spring 320 is 0.5-1 N / mm.

[0048] Please refer to Figures 10 and 11 for a second possible embodiment where the support ring 38′ has no axial movement relative to the clamp base 31′. The support ring 38′ has a radially outwardly extending abutment portion 383′ and a support portion 384′ extending toward the stepped portion 314′. The outer periphery of the support portion 384′ has several L-shaped grooves 3831′. The outer periphery of the second cylindrical portion 311′ near the stepped portion 314′ has several radially outwardly extending protrusions 3111′. These protrusions 3111′ can pass through the axial portion of the L-shaped groove 3831′ and then be rotated and engaged with the radial portion of the L-shaped groove 3831′, thereby stopping the support ring 38′ axially relative to the clamp base 31′; at the same time, it is used to abut against the first The sliding member 310' of a locking element 33' has at least one protrusion 3101' formed radially outward on its outer periphery. The support ring 38' also includes at least one stop groove 385', which extends from the front end face of the support ring 38' toward the stepped portion 314' and communicates with the radial portion of at least one L-shaped groove 3831'. The protrusion 3101' can move axially within the stop groove 385', which allows the sliding member 310' to move axially relative to the clamp base 31'. Since the sliding member 310' cannot rotate relative to the clamp base 31', the protrusion 3101' extending into the stop groove 385' makes the support ring 38' unable to rotate relative to the clamp base 31'. Specifically, in this embodiment, four L-shaped grooves 3831′ are evenly arranged along the outer periphery of the support portion 384′, and four corresponding protrusions 3111′ are also provided; two stop grooves 385′ are provided, which are connected to any two oppositely arranged L-shaped grooves 3831′, and two corresponding protrusions 3101′ are also provided.

[0049] The second spring 36′ is at least partially sleeved on the outer periphery of the support portion 384′, with one end abutting against the abutting portion 383′ of the support ring 38′ and the other end biasing against the second sleeve 34′ so that the second sleeve 34′ radially limits the second locking element 32′ to the locked position along the second through hole 312′; one end of the first spring 37′ abuts against the stepped portion 314′ and the other end biases against the sliding member 310′ against the first sleeve 35′ so that the first sleeve 35′ is radially limited to the locked position relative to the first locking element 33′ along the first through hole 313′; along the axial direction of the clamp base 31′, the second spring 36′ and the first spring 37′ at least partially overlap, which shortens the overall length of the tool clamp, which is beneficial to the miniaturization of the whole machine and facilitates construction in confined spaces;

[0050] Meanwhile, this embodiment also has a third spring, which is located on the other side of the abutment portion 383' of the support ring 38' relative to the second spring 36'. One end of the third spring abuts against the abutment portion 383', and the other end biases against the first sleeve 35'. It can also provide support force to the first sleeve 35' in each position, preventing the locking element from jamming and improving the user's operating comfort when inserting and removing the drill bit.

[0051] Please refer to Figures 12 and 13 for a third possible implementation of the support ring 38″ with no axial movement relative to the clamp base 31″. The support ring 38″ has several support arms 386″ extending toward the stepped portion 314″. At least one support arm 386″ has an inwardly bent end forming a hook portion 3861″. A generally L-shaped connecting channel 3112″ is formed on the outer surface of the second cylindrical portion 311″. The hook portion 3861″ can pass through the axial portion of the connecting channel 3112″ and then be engaged with the radial portion of the connecting channel 3112″ by rotation, thereby fixing the support ring 38″ axially relative to the clamp base 31″; and simultaneously used for At least one protrusion 3101" is formed on the outer periphery of the sliding member 310" that abuts against the first locking element 33" and at least one stop groove 385" is formed on the support arm 386". The stop groove 385" extends from the front end face of the support ring 38" toward the step portion 314" and the protrusion 3101" can move axially in the stop groove 385". This allows the sliding member 310" to move axially relative to the clamp base 31". Since the sliding member 310" cannot rotate relative to the clamp base 31", the protrusion 3101" extending into the stop groove 385" makes the support ring 38" unable to rotate relative to the clamp base 31. Specifically, in this embodiment, there are four support arms 386″, wherein any two support arms 386″ arranged opposite each other have hooks 3861″ formed at their ends, and there are two L-shaped connecting channels 3112″ corresponding to the hooks 3861″; there is one stop groove 385″, and there is one protrusion 3101″ corresponding to it.

[0052] The second spring 36″ is at least partially sleeved on the outer periphery of the support arm 386″, with one end biased against the support ring 38″ and the other end biased against the second sleeve 34″, so that the second sleeve 34″ radially limits the second locking element 32″ to the locked position along the second through hole 312″; one end of the first spring 37″ abuts against the step portion 314″ and the other end biases the sliding member 310″ against the first sleeve 35″, so that the first sleeve 35″ is radially limited to the locked position relative to the first locking element 33″ along the first through hole 313″; along the axial direction of the clamp base 31″, the second spring 36″ and the first spring 37″ at least partially overlap, which shortens the overall length of the tool clamp, which is beneficial to the miniaturization of the whole machine and facilitates construction in confined spaces;

[0053] Meanwhile, this embodiment also has a third spring, which is located on the other side of the abutment portion 383" of the support ring 38" relative to the second spring 36"; one end of the third spring abuts against the abutment portion 383" and the other end biases against the first sleeve 35"; it can also provide support force to the first sleeve 35" in each position, preventing the locking element from jamming and improving the user's operating comfort when inserting and removing the drill bit.

[0054] Please refer to Figure 4. The tool clamp 30 also includes a dust cover 330 disposed at the front end of the first sleeve 35. The dust cover 330 has an integrally formed protrusion 3301 inside. One end of the protrusion 3301 engages with the clamp base 31, and the other end forms a gap 3302 between it and the outer ring of the dust cover 330. The extension 353 extends into the gap 3302. If the dust cover 330 needs to be removed, the protrusion 3301 needs to move towards the gap 3302. At this time, the extension 353 can play a certain role in blocking the movement of the protrusion 3301. A large force is required to compress and deform the protrusion 3301 before the dust cover 330 can be removed. Therefore, the extension 353 extending into the gap 3302 plays a role in preventing the dust cover 330 from accidentally falling off.

[0055] In this embodiment, a tool clamp 30 is provided. The tool clamp 30 has a stepped portion 314 on its clamp base 31. A first locking mechanism and a second locking mechanism are respectively located on both sides of the stepped portion 314. A support ring 38 with no axial movement relative to the clamp base 31 is provided in front of the stepped portion 314. A first spring 37 of the first locking mechanism is fixedly disposed on the stepped portion 314 and is configured to apply an elastic force to the first locking mechanism to achieve locking. A second spring 36 of the second locking mechanism is fixedly disposed on the support ring 38 and is configured to apply an elastic force to the second locking mechanism to achieve locking. Therefore, along the axial direction of the clamp base 31, the first spring 37 and the second spring 36 at least partially overlap, shortening the axial dimension of the tool clamp 30 and optimizing the structural layout. At the same time, when the first locking mechanism is driven to unlock the tool head 200, the second spring 36 maintains its original pressure state, avoiding the need to overcome the forces of the first spring 37 and the second spring 36 simultaneously when pulling the first sleeve 35 during the release of the tool head 200, which would affect the operator's operating comfort.

[0056] In addition to the first spring 37 for providing pressure to lock the tool head 200 and the second spring 36 for providing pressure to lock the tool clamp 30 onto the electric hammer 100, the tool clamp 30 also has a third spring 320 between the first sleeve 35 and the support ring 38. The support ring 38 has no axial movement relative to the clamp base 31. Therefore, the third spring 320 can provide stable support force to the first sleeve 35 in any position. This prevents the first sleeve 35 from falling towards the second sleeve 34 due to the loss of support from the first spring 37 and the third spring 320 when the electric hammer 100 is inserted into the drill bit 200 and the sliding member 310 is pushed by the drill bit 200 and moves against the force of the first spring 37 towards the second sleeve 34, causing the first locking element 33 to jam and the drill bit 200 to be unable to be inserted or to be blocked from insertion.

[0057] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of protection of the claims.

Claims

1. A tool clamp for selectively mounting a tool head on an electric hammer, characterized in that: The tool fixture includes: A clamp base having a stepped portion; A first locking mechanism, at least partially located on one side of the stepped portion, is configured to selectively lock the tool head; The first locking mechanism includes a first spring, which is fixedly disposed on the step portion and configured to apply an elastic force to the first locking mechanism to achieve locking; The second locking mechanism, at least partially located on the other side of the step, is configured to be selectively locked to the electric hammer; The second locking mechanism includes a second spring and a support ring, the support ring being at least partially located in front of the stepped portion and having no axial movement relative to the clamp base, the second spring being fixedly disposed on the support ring and configured to apply an elastic force to the second locking mechanism for locking. Along the axial direction of the clamp base, the first spring and the second spring at least partially overlap, and when the first locking mechanism is driven to unlock the tool head, the second spring maintains its original pressure state.

2. The tool fixture according to claim 1, characterized in that: The clamp base includes a first cylindrical part and a second cylindrical part. The clamp base is composed of a first cylindrical part and a second cylindrical part that are coaxially arranged and have different radii. A step is formed at the connection between the first cylindrical part and the second cylindrical part. The first locking mechanism further includes: a first sleeve, a sliding member, and a first locking element; The first end of the first spring abuts against the stepped portion, and the second end of the first spring biases the slider against the first sleeve, so that the first spring applies an elastic force to the first locking element through the first sleeve to achieve locking; The second locking mechanism further includes: a second sleeve and a second locking element; The first end of the second spring biases the second sleeve, and the second end of the second spring biases the support ring, so that the second spring applies an elastic force to the second locking element through the second sleeve to achieve locking.

3. The tool fixture according to claim 2, characterized in that: Along the axial direction of the clamp base, the support ring and the slider at least partially overlap, and the slider is relatively movably disposed on the inner ring of the support ring.

4. The tool fixture according to claim 2, characterized in that: A stop ring is also fitted on the clamp base. The stop ring is located in front of the support ring and is connected to the clamp base without axial movement. The end of the support ring away from the second spring has a plurality of axially extending support claws. The first sleeve includes a plurality of axially extending through grooves inside. The support claws pass through the through grooves and abut against the stop ring.

5. The tool fixture according to claim 4, characterized in that: The first sleeve includes a plurality of axially forward-extending extensions, and the outer periphery of the stop ring includes a plurality of outwardly extending lugs, the lugs being located between every two of the extensions, and the support claw passing through the through groove abutting against the lugs.

6. The tool fixture according to claim 5, characterized in that: The tool fixture also includes a dust cover disposed at the front end of the first sleeve. The interior of the dust cover includes a protrusion that engages with the fixture base. A gap is formed between the protrusion and the outer ring of the dust cover, and the extension extends into the gap.

7. The tool fixture according to claim 2, characterized in that: The second sleeve has a locking ring fixed inside it, the locking ring surrounding the second locking element, and the support ring having a receiving groove facing the locking ring, with the second spring supported between the receiving groove and the locking ring; The locking ring, under the biasing force of the second spring, pushes the second locking element radially inward through the second through hole, so that the second locking element is in the locked position.

8. The tool fixture according to claim 7, characterized in that: The end of the second sleeve away from the first sleeve has a notch that allows the second locking element to move radially outward; By sliding the second sleeve, the locking ring moves against the force of the second spring toward the first sleeve to a position separated from the second locking element, and the second locking element can be moved radially into the notch to put the second locking element in the released position.

9. The tool fixture according to claim 2, characterized in that: The first sleeve has a pressure ring fixed inside it, the pressure ring having a pressure surface facing the first locking element; The sliding member is held inside the pressure ring by the bias force of the first spring, and the pressure surface presses the first locking element through the first through hole to put the first locking element in the locked position.

10. The tool fixture according to claim 9, characterized in that: The end of the pressing surface away from the sliding member has a guide slope, and the inner wall of the first sleeve facing the clamp base, together with the guide slope and the stop ring, forms a receiving space. Slide the first sleeve, and the first sleeve moves toward the first sleeve against the force of the first spring through the sliding member. The first locking element is disengaged from the radial limit of the pressing surface and can move into the receiving space so that the first locking element is in the released position. The first sleeve does not push the support ring to move axially throughout the entire travel stroke.

11. The tool fixture according to claim 1, characterized in that: The first locking mechanism further includes a third spring and a first sleeve. The third spring is disposed on the support ring and configured to apply a biasing pressure to the first sleeve to move it away from the step portion.

12. The tool fixture according to claim 11, characterized in that: The third spring provides support to the first sleeve in each position.

13. The tool fixture according to claim 11, characterized in that: The elastic coefficient of the third spring is less than that of the first spring, and the elastic coefficient of the first spring is less than that of the second spring.

14. The tool fixture according to claim 11, characterized in that: A stop ring is also fitted on the clamp base. The stop ring is located in front of the support ring and is connected to the clamp base without axial movement. The end of the support ring away from the first spring has a plurality of axially extending support claws. The first sleeve includes a plurality of axially extending through grooves inside. The support claws pass through the through grooves and abut against the stop ring. The third spring is at least partially fitted on the outer periphery of the support claws.

15. An electric hammer, the electric hammer comprising a housing, a motor housed within the housing, a rotating shaft driven by the motor, and a tool holder as claimed in any one of claims 1-14 connected to the rotating shaft.

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