Electric hammer
By introducing a partition part into the transmission assembly of the electric hammer, the chamber between the rotary sleeve and the impact hammer is solved, and the operator's comfort is improved.
Patent Information
- Application Number
- CN202510387815.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-28
- Publication Date
- 2025-05-30
AI Technical Summary
When the existing electric hammer is working, the vibration caused by the rotating sleeve during impact causes the operator to feel uncomfortable during use, causing the hands to be numb.
By introducing a partition part into the transmission assembly, the chamber between the rotary sleeve and the hammer is separated, so that the compressed gas during the hammer is prevented from directly acting on the rotary sleeve when the hammer is impacted, thereby reducing vibration.
It effectively reduces vibration caused by the movement of the sleeve, improves the operator's comfort and reduces use fatigue.
Smart Images
Figure CN120056047A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of tools, and particularly to a hammer drill. Background Art
[0002] With the increasing development of power tools, impact power tools used for chiseling or drilling on the surfaces of workpieces with relatively high hardness such as walls and concrete are increasingly favored by consumers.
[0003] In related technologies, a hammer drill has a rotation mechanism and an impact mechanism. The rotation mechanism can provide a rotational force to the working head, and the impact mechanism can provide an impact force to the working head. In the impact mechanism, the cylinder and the rotating sleeve can rotate synchronously while moving axially relative to each other. The piston in the cylinder reciprocates back and forth under the driving force of the motor, and drives the ram in the cylinder to reciprocate. The ram impacts the striker in the rotating sleeve, and the striker transmits the impact force to the working head to perform drilling and impact on the working surface.
[0004] However, in the prior art, when the hammer drill is working, the rotating sleeve that moves back and forth under impact will generate relatively large vibrations, making the operator feel uncomfortable and experiencing a numb hand phenomenon during use. Summary of the Invention
[0005] Based on this, in view of the vibration problem of the hammer drill, it is necessary to provide a hammer drill.
[0006] To solve the above technical problems, the present application is implemented as follows: In one embodiment, a hammer drill is provided, including: a housing; a motor disposed in the housing for providing a driving force; a chuck assembly for clamping a working head; a transmission assembly configured to receive the driving force of the motor and act on the working head; the transmission assembly includes a cylinder, a piston, a ram, a striker, and a rotating sleeve. The cylinder is a hollow cylindrical member and is rotatably supported in the housing. The rotating sleeve is a hollow cylindrical member and at least part of it is disposed in the cylinder. The piston, the ram, the striker, and the rotating sleeve are sequentially disposed in the cylinder along the rotational axis direction of the cylinder. The piston receives the driving force of the motor and reciprocates back and forth in the cylinder. At least part of the striker is disposed in the rotating sleeve; Further, the transmission assembly further includes a partition portion. The partition portion and the rotating sleeve form a first chamber, and the partition portion and the ram form a second chamber.
[0007] Further, the partition portion is fixedly connected to or separately provided from the striker.
[0008] Further, the partition portion is further provided with a current passage portion that communicates the first chamber and the second chamber.
[0009] Further, the projected area of the current passage portion along the rotational axis direction of the cylinder accounts for 0.01 to 0.05 of the projected area of the inner hole of the cylinder.
[0010] Further, the current - passing part is configured as a through - hole, and the opening size of the current - passing part on the side of the partition part facing the ram is greater than or equal to the opening size of the current - passing part on the side of the partition part facing the rotating sleeve.
[0011] Further, the current - passing part is configured as a notch formed by the radial inward depression of the outer peripheral wall of the partition part, and the width of the notch decreases radially inward along the partition part.
[0012] Further, the current - passing part is arranged within the radial range between the partition part and the cylinder, and the current - passing part is annular.
[0013] Further, there are multiple current - passing parts, and the multiple current - passing parts are evenly arranged circumferentially along the rotation axis of the cylinder.
[0014] Further, the side of the partition part facing the ram is configured as a curved surface protruding outward from the center.
[0015] Further, the peripheral wall of the cylinder is provided with a through - hole, one side of the through - hole communicates with the outside of the cylinder, and the other side communicates with the first chamber.
[0016] In the embodiment of the present application, by separating the chamber between the rotating sleeve and the ram, it is avoided that the compressed gas formed during the impact of the ram directly acts on the rotating sleeve, reducing the vibration caused by the movement of the rotating sleeve, so as to improve the comfort of the operator. Description of the Drawings
[0017] Figure 1 It is a three - dimensional structural schematic diagram of a hammer drill in an embodiment of the present application; Figure 2 It is a partial cross - sectional view of a hammer drill in an embodiment of the present application; Figure 3 It is a partially enlarged view of a hammer drill in an embodiment of the present application; Figure 4 It is a schematic diagram of the partition part of the first embodiment of the present application; Figure 5 It is a schematic diagram of the current - passing part of the second embodiment of the present application; Figure 6 It is a schematic diagram of the current - passing part of the third embodiment of the present application; Figure 7 It is a partially enlarged view of a hammer drill in an embodiment of the present application; Description of the Drawings: 1. Outer shell; 11. Transmission housing; 12. Motor housing; 2. Handle assembly; 3. Chuck assembly; 31. Working head; 311. First groove; 32. Spring; 4. Auxiliary handle; 5. Motor; 6. Transmission housing; 61. Cylinder; 61a. First chamber; 61b. Second chamber; 611. Second through hole; 612. Vent hole; 62. Piston; 63. Ram; 64. Ram rod; 641. Third groove; 65. Sleeve; 651. Hollow part; 652. First through hole; 653. Second groove; 654. Third through hole; 66. First limiting member; 67. Second limiting member; 68. Third limiting member; 69. Partition part; 691. Current passing part. Detailed implementation manners
[0018] In order to make the above objects, features and advantages of the present application more obvious and understandable, the following will describe the detailed implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.
[0019] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.
[0020] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.
[0021] In this application, unless otherwise clearly defined or limited, terms such as "installed", "connected", "joined", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0022] In this application, unless otherwise clearly defined or limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is less than that of the second feature.
[0023] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation.
[0024] Refer to Figure 1 , FIG. 1 shows a schematic perspective view of a hammer drill in an embodiment of this application, including a housing 1, a handle assembly 2, a chuck assembly 3, and an auxiliary handle 4. Among them, the handle assembly 2 is disposed on the rear end side of the housing 1, the chuck assembly 3 is disposed on the front end side of the housing 1 away from the handle assembly 2, and the auxiliary handle 4 is detachably connected to the housing 1 and is disposed between the handle assembly 2 and the chuck assembly 3.
[0025] The housing 1 includes a transmission housing 11 and a motor housing 12, and the transmission housing 11 and the motor housing 12 are fixedly connected.
[0026] Refer to Figure 2 , Figure 2A partial cross-sectional view of a hammer drill according to an embodiment of the present application is shown, including a motor 5 (not visible in the figure) and a transmission assembly 6. The motor 5 is housed in a motor housing 12 and is used to output a driving force. The transmission assembly 6 is arranged in a transmission housing 11 and receives the driving force of the motor 5 to drive a working head 31 clamped in a chuck assembly 3 to move. The working head 31 can optionally rotate along its own axis and / or reciprocate back and forth along its own axis direction.
[0027] The transmission assembly 6 includes a cylinder 61, a piston 62, a ram 63, a ram rod 64, and a swivel 65. The cylinder 61 is a hollow cylindrical member and is rotatably supported in the transmission housing 11; the swivel 65 is a hollow cylindrical member and can reciprocate back and forth along the rotation axis direction of the cylinder 61 and rotate integrally with the cylinder 61 around the rotation axis. At least part of the swivel 65 is accommodated in the cylinder 61 and at least part of it protrudes from the cylinder 61; the ram 64 is always arranged inside the cylinder 61; the piston 62, the ram 63, the ram rod 64, and the swivel 65 are arranged in the cylinder 61 in sequence along the rotation axis direction of the cylinder 61. The piston 62 receives the driving force of the motor 5 and reciprocates back and forth inside the cylinder 61, and drives the movement of the ram 63 and the ram rod 64; at least part of the ram rod 64 is accommodated in the swivel 65 and at least part of it protrudes in the swivel 65 and is accommodated in the cylinder 61.
[0028] The chuck assembly 3 is sleeved on the swivel 65, and a spring 32 is further arranged at the rear end of the chuck assembly 3. The spring 32 is axially clamped between the chuck assembly 3 and the cylinder 61. When the chuck assembly 3 receives a driving force axially towards the cylinder 61 side, the spring 32 is compressed and approaches the cylinder 61.
[0029] The working head 31 is inserted into the hollow part 651 of the swivel 65, rotates integrally with the swivel 65, and is axially restricted in its movement range. Specifically, the swivel 65 is further provided with a first limiting member 66. The peripheral wall of the swivel 65 is provided with a first through hole 652, and the outer periphery of the working head 31 is provided with an axially extending first groove 311. At least part of the first limiting member 66 is accommodated in the first through hole 652 and is axially restricted on the swivel 65. At least part of the first limiting member 66 is accommodated in the first groove 311 and can move in the first groove 311.
[0030] The swivel 65 is accommodated in the hollow part 611 of the cylinder 61, rotates integrally with the cylinder 61, and is axially restricted in its movement range. Specifically, the cylinder 61 is further provided with a second limiting member 67. The peripheral wall of the cylinder 61 is provided with a second through hole 611, and the outer periphery of the swivel 65 is provided with an axially extending second groove 653. At least part of the second limiting member 67 is accommodated in the second through hole 611 and is axially restricted on the cylinder 61. At least part of the second limiting member 67 is accommodated in the second groove 653 and can move in the second groove 653.
[0031] The striking rod 64 is received in the hollow portion 651 of the rotating sleeve 65, rotates integrally with the rotating sleeve 65, and is axially restricted in its movement range. Specifically, the rotating sleeve 65 is further provided with a third restricting member 68. The peripheral wall of the rotating sleeve 65 is provided with a third through hole 654, and the outer periphery of the striking rod 64 is provided with an axially extending third groove 641. The third restricting member 68 is at least partially received in the third through hole 654 and is axially restricted on the rotating sleeve 65. The third restricting member 68 is at least partially received in the third groove 641 and is movable in the third groove 641.
[0032] A sealing assembly is further provided between the cylinder 61 and the rotating sleeve 65, and another sealing assembly is further provided between the rotating sleeve 65 and the striking rod 65. The two sealing assemblies restrict the overflow of grease and gas, enabling the transmission assembly 6 to have a relatively long service life.
[0033] During operation, the operator holds the handle assembly 2 and applies a thrust in the impact direction to the working head 31. The working head 31 abuts against the working surface, and the working head 31 moves in the direction towards the cylinder 61 against the elastic force of the spring 32. The first restricting member 66 moves to the left side of the first groove 311, and the second restricting member 67 moves in the second groove 653 following the compression amount of the spring 311. Therefore, when a relatively large impact is received on the side of the rotating sleeve 65 close to the hammer 63, the rotating sleeve 65 has a tendency to move towards the chuck assembly 3.
[0034] Refer to Figure 3 , Figure 3 shows a partial enlarged view of a hammer drill in an embodiment of the present application. In some embodiments of the present application, the transmission assembly 6 further includes a partition portion 69. The partition portion 69 is disposed in the cylinder 61 and is located between the rotating sleeve 65 and the hammer 63. The partition portion 69 and the rotating sleeve 65 form a first chamber 61a, and the partition portion 69 and the hammer 63 form a second chamber 61b. By separating the original cavity between the rotating sleeve 65 and the hammer 63 into two chambers through the partition portion 69, it is possible to effectively prevent the hammer 63 from directly applying axial pressure to the rotating sleeve 65 during the rapid reciprocating movement back and forth, thereby reducing the vibration of the hammer drill and further alleviating the fatigue of the operator during use.
[0035] In some embodiments of the present application, the partition portion 69 and the striking rod 64 are fixedly arranged. The partition portion 69 is disposed at the end side of the striking rod 64 close to the hammer 63. The partition portion 69 and the striking rod 64 can be integrally formed or can be detachably separated. Specifically, the integrally formed partition portion 69 and striking rod 64 can be made of metal products, which improves the service life of the material; for the detachably separated partition portion 69 and striking rod 64, the fastening methods can be threaded fastening connection, snap connection or interference fit, etc. The striking rod 64 can be made of metal products, and the partition portion 69 can be made of metal products or can be made of plastic products.
[0036] In some embodiments of the present application, the partition portion 69 and the striker 64 may also be separately provided. The partition portion 69 and the striker 64 slide relative to each other along the rotation axis direction of the cylinder 61. Optionally, the partition portion 69 is disposed between the striker 64 and the rammer 63. The partition portion 69 can be made of metal products to improve the strength of the partition portion 69. Optionally, the partition portion 69 is sleeved on the striker 64. The partition portion 69 slides on the striker 64 under the axial pressure of the rammer 63. The partition portion 69 can be made of metal products to improve the service life of the partition portion 69, or can be made of plastic products to reduce the weight of the whole machine and improve the comfort of use.
[0037] In some embodiments of the present application, the partition portion 69 is further provided with a flow-through portion 691. The flow-through portion 691 communicates the first chamber 61a and the second chamber 61b. It can be understood that when the partition portion 69 moves toward the side of the rotating sleeve 65 under the axial pressure, the gas in the first chamber 61a can flow through the flow-through portion 691 into the second chamber 61b to relieve the gas pressure in the first chamber 61a, thereby reducing the axial pressure exerted on the rotating sleeve 65 by the gas pressure, and further reducing the vibration of the whole machine. An air exchange hole 612 is also provided on the peripheral wall of the cylinder 61. The air exchange hole 612 communicates the internal space of the cylinder 61 and the external space of the cylinder 61. When the rammer 63 moves toward the partition portion 69 under the drive of the piston 62, if the partition portion 69 is on the side of the air exchange hole 612 close to the rotating sleeve, the gas in the second chamber 61b flows out of the air exchange hole 612 to the external space of the cylinder 61 to reduce the gas pressure in the second chamber 61b and avoid energy loss caused by excessive gas pressure, so as to improve the efficiency of energy transfer from the rammer 63 to the striker 64. If the partition portion 69 is on the side of the air exchange hole 612 close to the rammer 63, the gas in the second chamber 61b reaches the first chamber 61a through the flow-through portion 691 and can further reach the external space of the cylinder 61 through the air exchange hole 612, thereby reducing the gas pressure in the second chamber 61b and avoiding energy loss caused by excessive gas pressure, so as to improve the efficiency of energy transfer from the rammer 63 to the striker 64.
[0038] In some embodiments of the present application, the projected area of the flow-through portion 691 along the rotation axis direction of the cylinder 61 accounts for 0.01 to 0.05 of the projected area of the inner hole of the cylinder 61. The above ratio less than or equal to 0.05 can prevent the gas in the second chamber 61b from quickly entering the first chamber 61a, applying a large axial pressure to the rotating sleeve 65, and further reducing the vibration of the whole machine. The above ratio greater than or equal to 0.01 can guide the discharge of gas when it is necessary to discharge the gas in the first chamber 61a, or can discharge the gas in the second chamber 61b from the flow-through portion 691 when the rammer 63 impacts toward the rotating sleeve 65, reduce the energy loss caused by compressed gas, and increase the impact force of the rammer 63 on the striker 64.
[0039] Refer to Figure 4 , Figure 4 which shows a schematic diagram of the partition part of the first embodiment of the present application. In some embodiments of the present application, the current-carrying part 691 is configured as a through hole, and the opening size of the current-carrying part 691 on the side of the partition part 69 facing the ram 63 is greater than or equal to the opening size of the current-carrying part 691 on the side of the partition part 69 facing the rotating sleeve 65. At this time, when the ram 63 moves rapidly towards the rotating sleeve 65, the gas in the second chamber 61b can flow quickly into the first chamber 61a, reducing the energy loss caused by the compressed gas and increasing the impact force of the ram 63 on the striker 64. Optionally, the smaller opening diameter of the current-carrying part 691 is between 2 mm and 4 mm. Optionally, there are multiple current-carrying parts 691, and they are arranged axially and evenly around the rotation axis of the cylinder 61 on the partition part 69.
[0040] Refer to Figure 5 , Figure 5 which shows a schematic diagram of the partition part of the second embodiment of the present application. In some embodiments of the present application, the current-carrying part 691 is configured as a notch formed by the radially inward depression of the outer peripheral wall of the partition part 69, and the notch width decreases radially inward along the partition part 69. Optionally, the notch is "V"-shaped, so that it can be formed by a mold at one time, avoiding secondary processing. Optionally, there are multiple current-carrying parts 691, and they are arranged axially and evenly around the rotation axis of the cylinder 61 on the partition part 69.
[0041] Refer to Figure 6 , Figure 6 which shows a schematic diagram of the partition part of the third embodiment of the present application. In some embodiments of the present application, the current-carrying part 691 is arranged within the radial range between the outer diameter of the partition part 69 and the inner hole of the cylinder 61, and the current-carrying part 691 is annular. At this time, the current-carrying part 691 is arranged on the circumferential side of the partition part 69, and the gas flow between the first chamber 61a and the second chamber 61b is uniform and stable.
[0042] In some embodiments of the present application, the side of the partition part 69 facing the ram 63 is configured as a curved surface protruding outward from the center. When the ram 63 impacts the partition part 69, it can ensure the dispersion of the impact force, relieve the impact fatigue of the partition part 69, and increase the service life of the partition part 69.
[0043] Refer to Figure 7 , Figure 7The partial enlarged view of the electric hammer in an embodiment of the present application is shown. In some embodiments of the present application, an air exchange hole 613 is arranged on the peripheral wall of the cylinder 61. One side of the air exchange hole 613 communicates with the external space of the cylinder 61, and the other side communicates with the first chamber 61a. Optionally, a plurality of air exchange holes 613 are provided and are circumferentially and uniformly arranged along the rotation axis direction of the cylinder 61. Arranging the air exchange holes 613 in this way can quickly discharge the compressed gas in the chamber 61a, thereby reducing the axial pressure on the rotating sleeve 65 and improving the comfort of the operator.
[0044] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.
[0045] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.
Claims
1. An electric hammer, comprising: shell; a motor, disposed in the housing, for providing a driving force; A chuck assembly, used for clamping a working head; A transmission assembly, configured to receive the driving force of the motor and act on the working head; The transmission assembly includes a cylinder, a piston, a hammer, a striker, and a rotating sleeve. The cylinder is a hollow cylindrical component and is rotatably supported in the housing. The rotating sleeve is a hollow cylindrical component and is at least partially arranged in the cylinder. The piston, the hammer, the striker, and the rotating sleeve are sequentially arranged in the cylinder along the rotation axis direction of the cylinder. The piston receives the driving force of the motor and reciprocates back and forth in the cylinder. The striker is at least partially arranged in the rotating sleeve. It is characterized in that the transmission assembly also includes a partition part, the partition part and the rotating sleeve form a first chamber, and the partition part and the hammer form a second chamber.
2. The electric hammer according to claim 1, characterized in that: The partition part is fixedly connected to the striker or is separately arranged.
3. The electric hammer according to claim 1, characterized in that: The partition portion is further provided with an over-flow portion, and the over-flow portion communicates the first chamber and the second chamber.
4. The electric hammer according to claim 3, characterized in that: The projection area of the flow portion along the rotation axis direction of the cylinder accounts for 0.01 to 0.05 of the projection area of the inner hole of the cylinder.
5. The electric hammer according to claim 3, characterized in that: The flow-through portion is configured as a through hole, and the opening size of the flow-through portion on the side of the partition portion toward the hammer is greater than / equal to the opening size of the flow-through portion on the side of the partition portion toward the rotating sleeve.
6. The electric hammer according to claim 3, characterized in that: The flow-through portion is configured as a notch that is recessed radially inwardly on the outer peripheral wall of the partition portion, and the width of the notch decreases radially inwardly along the partition portion.
7. The electric hammer according to claim 3, characterized in that: The flow-through portion is arranged in a radial range between the partition portion and the cylinder, and the flow-through portion is annular.
8. The electric hammer according to claim 3, characterized in that: There are a plurality of flow passages, and the plurality of flow passages are evenly arranged along the circumferential direction of the rotation axis of the cylinder.
9. The electric hammer according to claim 1, characterized in that: The side of the partition portion facing the hammer is configured as a curved surface with a center convex outward.
10. The electric hammer according to claim 1, characterized in that: A through hole is disposed on the peripheral wall of the cylinder, one side of the through hole is connected to the outside of the cylinder, and the other side of the through hole is connected to the first chamber.