Impact wrench and impact wrench impact assembly
By designing a curved meshing contact structure and stress relief groove in the impact wrench, the problem of instantaneous contact between the impact hammer and the output shaft is solved, thereby reducing impact force and noise, extending the service life of the equipment, and reducing maintenance costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANDONG WEIDA MACHINERY CO LTD
- Filing Date
- 2025-03-17
- Publication Date
- 2026-04-14
AI Technical Summary
The instantaneous contact between the impact hammer and the output shaft of existing impact wrenches, formed by a ball or cam structure, results in high impact force and noise, which can easily cause the impact part to break, affecting service life and maintenance costs.
The contact surface between the impact hammer and the output shaft of the impact wrench is designed as a curved surface structure, using involute curved surface meshing contact, combined with stress relief grooves to optimize stress distribution, reduce impact force and noise.
It effectively reduces impact and noise, prevents parts from breaking, extends equipment life, and improves durability and operational efficiency.
Smart Images
Figure CN224116076U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of impact wrench technology, and more specifically, relates to an impact wrench and an impact wrench impact component. Background Technology
[0002] An impact wrench is a common handheld power tool that uses impact force to drive the rotation of bolts, nuts, and other components to tighten or loosen them.
[0003] In existing impact wrench impact assemblies, the impact hammer and output shaft form dynamic contact through a ball or cam structure. The impact surface between the impact hammer and the output shaft is a planar instantaneous contact structure, resulting in a large instantaneous impact force and impact noise. During repeated impacts, stress concentration is easily generated at the geometric change points of the impact hammer, which can easily cause the impact part to break, affecting the service life of the impact component and resulting in high maintenance costs. Utility Model Content
[0004] This utility model addresses the technical problems existing in the prior art by providing an impact wrench and an impact wrench impact component.
[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:
[0006] An impact wrench impact assembly includes an impact hammer and an impact wrench output shaft. The impact hammer and the impact wrench output shaft are in contact connection. The impact hammer is provided with a first mating part, and the impact wrench output shaft is provided with a second mating part adapted to and connected to the first mating part. The first mating part is provided with a first curved surface, and the second mating part is provided with a second curved surface. The first curved surface and the second curved surface dynamically cooperate to form a curved surface contact structure.
[0007] Preferably, the impact hammer includes an impact boss and an impact bottom surface, and a first mating part is disposed between the impact boss and the impact bottom surface, and the first mating part has at least one first curved surface.
[0008] Preferably, the first mating part is disposed between the inner peripheral side of the impact boss and the outer peripheral side of the impact bottom surface, the first curved surface is perpendicular to the impact bottom surface, and the first curved surface is an involute curved surface structure.
[0009] Preferably, the impact wrench output shaft includes an output shaft body and an engagement extension. The engagement extension is disposed at the end of the output shaft body and extends outward along the radial direction of the output shaft body. A second mating part is disposed on the engagement extension. The second mating part has at least one second curved surface that is adapted to and connected to the first curved surface.
[0010] Preferably, the meshing extension has two extension ends that extend radially outward along the main body of the output shaft, and the outer circumferential surface of the extension ends has an arcuate surface structure.
[0011] The second curved surface is located on the outer periphery of the extension end, and the second curved surface is an involute curved surface structure that is adapted to the first curved surface.
[0012] Preferably, the dimensions of the first curved surface and the second curved surface are adapted to each other, and the first mating part and the second mating part form an interlocking contact structure, and the two form a complementary curved surface nesting structure in the contact area.
[0013] Preferably, a stress relief groove is provided on the outer periphery of the impact bottom surface, and the stress relief groove is an arc-shaped groove structure arranged along the axial direction of the impact hammer.
[0014] Preferably, the stress relief groove is an annular groove structure arranged circumferentially along the impact bottom surface, and the stress relief groove is located at the lower axial end of the first mating part and the second mating part.
[0015] Preferably, both the impact hammer and the impact wrench output shaft have a centrally symmetrical structure.
[0016] Furthermore, this utility model also provides an impact wrench, including the aforementioned impact wrench impact component.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] This utility model has a simple structure. By setting the contact surface between the impact hammer of the impact assembly and the output shaft of the impact wrench to a curved surface structure, the instantaneous contact between the output shaft and the impact hammer during operation changes from a planar instantaneous contact to a curved surface contact, which plays a role in mitigating the impact force. Through the contact connection of the first curved surface and the second curved surface, the instantaneous impact force and impact noise generated by the impact hammer and the output shaft of the impact wrench are reduced, preventing the breakage of the impact parts of each component, improving the performance of the components, and extending the service life of the equipment. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a three-dimensional structural diagram of an embodiment of the impact component of this utility model;
[0021] Figure 2 This is a top view of an embodiment of the impact component of this utility model;
[0022] Figure 3 This is a three-dimensional structural diagram of an embodiment of the impact hammer of this utility model;
[0023] Figure 4This is a top view of an embodiment of the impact hammer of this utility model;
[0024] Figure 5 This utility model Figure 4 Sectional view along the AA direction;
[0025] Figure 6 This is a three-dimensional structural diagram of an embodiment of the impact wrench output shaft of this utility model;
[0026] Figure 7 This is a top view of an embodiment of the impact wrench output shaft of this utility model.
[0027] A schematic diagram of the embodiment.
[0028] Explanation of symbols in the diagram:
[0029] 1. Impact hammer; 11. First curved surface; 12. Impact boss; 13. Impact bottom surface; 14. Stress relief groove;
[0030] 2. Impact wrench output shaft; 21. Second curved surface; 22. Output shaft body; 23. Engaging extension; 24. Reinforcing part. Detailed Implementation
[0031] To make the technical problem to be solved, the technical solution, and the beneficial effects of this application clearer, the following describes in further detail an impact wrench and an impact wrench impact assembly provided by this application, in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.
[0032] Example 1
[0033] Please see Figure 1 This embodiment provides an impact wrench impact assembly, including an impact hammer and an impact wrench output shaft. The impact hammer 1 and the impact wrench output shaft 2 are in contact connection. The impact hammer 1 is provided with a first mating part, and the impact wrench output shaft 2 is provided with a second mating part adapted to and connected to the first mating part. The first mating part is provided with a first curved surface 11, and the second mating part is provided with a second curved surface 21. The first curved surface 11 and the second curved surface 21 dynamically cooperate to form a curved surface contact structure.
[0034] This utility model has a simple structure. By setting the contact surface between the impact hammer 1 of the impact assembly and the output shaft 2 of the impact wrench to a curved surface structure, the instantaneous contact between the output shaft and the impact hammer during operation changes from a planar instantaneous contact to a curved surface contact, which plays a role in mitigating the impact force. Through the cooperation and contact connection of the first curved surface 11 and the second curved surface 21, the instantaneous impact force and impact noise generated by the impact hammer 1 and the output shaft 2 of the impact wrench are reduced, preventing the breakage of the impact parts of each component, improving the performance of the components, and extending the service life of the equipment.
[0035] In this embodiment, as Figure 2 , Figure 3 As shown, the impact hammer 1 includes an impact boss 12 and an impact bottom surface 13. A first mating part is disposed between the impact boss 12 and the impact bottom surface 13. The first mating part has at least one first curved surface 11.
[0036] Specifically, the impact hammer 1 has a circular outer cross-section and an axially penetrating connecting hole inside. The impact boss 12 and the impact bottom surface 13 are both located at the end that connects with the output shaft 2 of the impact wrench. The impact bottom surface 13 is a planar structure and is located at the bottom of the impact hammer 1. The impact bottom surface 13 and the radial upper plane of the impact boss 12 are parallel to each other. The first mating part is vertically arranged and is located between the inner circumference of the impact boss 12 and the outer circumference of the impact bottom surface 13.
[0037] The first curved surface 11 of the first mating part is perpendicular to the impact bottom surface 13. The upper end of the first curved surface 11 is in contact with the upper end face of the impact boss 12, and the lower end of the first curved surface 11 is connected to the outer periphery of the impact bottom surface 13.
[0038] Furthermore, in this embodiment, the first curved surface 11 is disposed on the upper inner sidewall of the impact hammer 1. The first curved surface 11 is an involute curved surface structure. The first mating part is provided with four first curved surfaces 11. Two adjacent first curved surfaces 11 are disposed on each opposite side of the first mating part. A buffer surface is disposed between the two adjacent first curved surfaces 11. The buffer surface and the first curved surface 11 are both curved surface structures composed of a single or multiple arc surfaces.
[0039] Furthermore, such as Figure 4 , Figure 5 As shown, a stress relief groove 14 is provided on the outer periphery of the impact bottom surface 13. The stress relief groove 14 is located at the lower end of the inner sidewall of the impact boss 12, and the stress relief groove 14 is located in the lower part of the axial direction of the impact bottom surface 13. The stress relief groove 14 is an arc-shaped groove structure arranged along the axial direction of the impact hammer 1.
[0040] Specifically, the stress relief groove 14 is located at the lower axial end where the first mating part and the second mating part are in contact. The stress relief groove 14 is located on the outer periphery of the impact bottom surface 13 and is arranged along the circumference of the impact bottom surface 13. The stress relief groove 14 is an annular groove structure, and the radial cross section of the stress relief groove 14 is adapted to the shape of the impact bottom surface 13.
[0041] This embodiment optimizes stress distribution by setting a stress relief groove 14 at the lower part of the contact end between the impact hammer 1 and the output shaft 2 of the impact wrench, eliminating stress concentration generated by the impact hammer 1 during repeated impacts and reducing local peak stress. Moreover, when the impact hammer 1 impacts at high speed, the stress relief groove 14 can absorb part of the impact energy, avoid the superposition effect caused by stress wave reflection, reduce the risk of instantaneous overload, further reduce the damage to parts and working noise caused by impact force, delay the initiation and propagation of fatigue cracks in the impact part, thereby improving the durability and working efficiency of the impact hammer.
[0042] In this embodiment, as Figure 6 , Figure 7 As shown, the impact wrench output shaft 2 includes an output shaft body 22 and an engagement extension 23. The engagement extension 23 is disposed at the end of the output shaft body 22 and extends outward along the radial direction of the output shaft body 22. A second mating part is disposed on the engagement extension 23. The second mating part has at least one second curved surface 21 that is adapted to and connected to the first curved surface 11.
[0043] Specifically, the engagement extension 23 is located at one end of the impact transmission between the impact wrench output shaft 2 and the impact hammer 1. The engagement extension 23 has two extension ends that extend radially outward along the output shaft body 22. The two extension ends are arranged opposite each other and are respectively located on the left and right sides of the output shaft body 22 in the radial direction. The two extension ends are symmetrically arranged along the radial direction of the output shaft body 22. Each extension end has an axisymmetric structure. The second mating part is located on the side of the engagement extension 23. The outer periphery of the engagement extension end has an arcuate surface structure. Each extension end has two second curved surfaces 21 on its outer periphery. The second curved surface 21 is an involute curved surface structure that is adapted to the first curved surface 11.
[0044] Furthermore, in this embodiment, the dimensions of the first curved surface 11 and the second curved surface 21 are adapted to each other, and the first mating part and the second mating part form an interlocking contact structure. The first curved surface 11 is a concave arc surface, and the second curved surface 21 is a convex arc surface. The two form a complementary curved surface nesting structure in the contact area.
[0045] Since each extension end is provided with two second curved surfaces 21 as impact surfaces, one of the second curved surfaces 21 on each extension end of the impact wrench output shaft 1 contacts a first curved surface 11 on the impact hammer 1 that is oppositely arranged on both sides, so that the output shaft and the impact hammer change from instantaneous planar contact to involute meshing contact. During the operation, the two parts change from instantaneous surface contact to meshing connection, which plays a role in mitigating the impact force, effectively reducing the damage caused by the impact force to the parts, avoiding breakage of the impact part, and extending the service life of the parts.
[0046] Furthermore, in this embodiment, as Figure 6As shown, the output shaft 2 of the impact wrench also includes a reinforcing part 24, which is disposed between the output shaft body 22 and the engagement extension 23. The reinforcing part 24 strengthens the connection between the output shaft body 22 and the engagement extension 23, thereby improving the stability of the connection and the transmission of torque.
[0047] Specifically, the reinforcing part 24 is an annular plate-shaped structure provided on the outer periphery of the end of the output shaft body 22. The reinforcing part 24, the output shaft body 22, and the engagement extension part 23 are concentrically arranged, and the reinforcing part 24 and the engagement extension part 23 are an integral structure. The outer periphery of the reinforcing part 24 is smaller than the middle outer periphery of the engagement extension part 23.
[0048] Furthermore, in a preferred embodiment of this utility model, both the impact hammer 1 and the impact wrench output shaft 2 are centrally symmetrical structures, which not only facilitates processing and operation, but also better transmits torque during the dynamic energy transfer process.
[0049] Furthermore, in this embodiment, the specific arc and curvature of the first curved surface 11 and the second curved surface 21 can be adapted and adjusted according to the actual usage requirements of the impact wrench. During the impact process, the dynamic contact area of the curved surface contact structure accounts for more than 80% of the theoretical contact area.
[0050] Example 2
[0051] This embodiment provides an impact wrench, including the impact wrench impact component described above, thereby having all the beneficial effects of an impact component. Its structure and principle will not be described in detail here.
[0052] This utility model provides an impact wrench and impact wrench impact assembly with a simple structure and easy processing. By setting the contact surface between the impact hammer 1 of the impact assembly and the output shaft 2 of the impact wrench to a curved surface structure, the instantaneous contact between the output shaft and the impact hammer during operation changes from a planar instantaneous contact to a curved surface contact, which plays a role in mitigating the impact force. By designing the impact surface of the impact assembly as an involute curved surface structure, the first curved surface 11 and the second curved surface 21 are meshed and connected, which reduces the instantaneous impact force and impact noise generated by the impact hammer and the output shaft of the impact wrench, prevents the breakage of the impact parts of each component, improves the performance of the components, extends the service life of the equipment, and reduces maintenance costs.
[0053] Furthermore, this invention optimizes stress distribution by setting a stress relief groove 14 on the impact bottom surface 13 at the lower part of the contact end between the impact hammer 1 and the output shaft 2 of the impact wrench, eliminating stress concentration generated by the impact hammer 1 during repeated impacts and reducing local peak stress. Moreover, when the impact hammer 1 impacts at high speed, the stress relief groove can absorb part of the impact energy, avoid the superposition effect caused by stress wave reflection, reduce the risk of instantaneous overload, further reduce the damage and working noise caused by the impact force to the parts, delay the initiation and propagation of fatigue cracks in the impact part, thereby improving the durability and reliability of the impact hammer, and making it suitable for industrial scenarios with high frequency and high impact load.
[0054] In the description of this utility model, it should be understood that terms such as “length”, “width”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, and “outer” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0056] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. An impact wrench impact assembly, comprising an impact hammer and an impact wrench output shaft, wherein the impact hammer and the impact wrench output shaft are in contact connection, characterized in that, The impact hammer is provided with a first mating part, and the output shaft of the impact wrench is provided with a second mating part adapted to and connected to the first mating part. The first mating part is provided with a first curved surface, and the second mating part is provided with a second curved surface. The first curved surface and the second curved surface dynamically cooperate to form a curved surface contact structure. The first mating part and the second mating part form a complementary curved surface nesting structure in the contact area. The impact hammer includes an impact boss and an impact bottom surface. The outer periphery of the impact bottom surface is provided with a stress relief groove. The stress relief groove is an arc-shaped groove structure arranged along the axial direction of the impact hammer.
2. The impact wrench impact assembly according to claim 1, characterized in that, The first mating part is disposed between the impact boss and the impact bottom surface, and the first mating part has at least one first curved surface.
3. The impact assembly for an impact wrench according to claim 2, characterized in that, The first mating part is disposed between the inner peripheral side of the impact boss and the outer peripheral side of the impact bottom surface. The first curved surface is perpendicular to the impact bottom surface and is an involute curved surface structure.
4. An impact wrench impact assembly according to claim 1 or 2, characterized in that, The impact wrench output shaft includes an output shaft body and an engagement extension. The engagement extension is disposed at the end of the output shaft body and extends outward along the radial direction of the output shaft body. The second mating part is disposed on the engagement extension. The second mating part has at least one second curved surface that is adapted to and connected to the first curved surface.
5. The impact wrench impact assembly according to claim 4, characterized in that, The engagement extension is provided with two extension ends that extend radially outward along the main body of the output shaft, and the outer circumferential surface of the extension ends is an arc surface structure. The second curved surface is disposed on the outer periphery of the extension end, and the second curved surface is an involute curved surface structure adapted to the first curved surface.
6. The impact assembly for an impact wrench according to claim 1, characterized in that, The dimensions of the first curved surface and the second curved surface are adapted to each other, and the first mating part and the second mating part form an engaging contact structure.
7. The impact wrench impact assembly according to claim 1, characterized in that, The stress relief groove is an annular groove structure arranged circumferentially along the impact bottom surface, and the stress relief groove is located at the lower axial end of the first mating part and the second mating part.
8. The impact assembly for an impact wrench according to claim 1, characterized in that, Both the impact hammer and the impact wrench have a centrally symmetrical output shaft.
9. An impact wrench, characterized in that, Includes the impact wrench impact assembly as described in any one of claims 1-8.