Impact tool
By optimizing the baseline of the first groove of the spindle and adjusting the slope of the moving track of the steel ball, the problems of upper and lower impacts of the impact tool were solved, improving the user experience and lifespan.
Patent Information
- Application Number
- CN202423262161.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2034-12-27
AI Technical Summary
Existing impact tools are prone to upper and lower impacts during use, which affects the feel and shortens the service life, and existing adjustment methods are difficult to effectively avoid these collisions.
The baseline of the first groove of the spindle is optimized to change the slope of the moving track of the steel ball, thereby adjusting the movement process of the striking block to reduce the risk of upper and lower collisions. The angle range of the steel ball track is adjusted to match different working conditions.
It reduces the risk of impact from above and below the impact block, improves the handling and lifespan of the impact tool, and stabilizes the output torque.
Smart Images
Figure CN223700671U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to electric tool technical field especially impact tool. BACKGROUND
[0002] As Figure 1A and Figure 1B The existing impact tool (such as impact wrench, impact driver), mainly including motor, reduction mechanism, main shaft 1a, impact mechanism 2a and output shaft 3a arranged in sequence along the axial direction, impact mechanism 2a includes strike block 21a, steel ball and spring 22a, main shaft 1a is equipped with first V type groove 11a, strike block 21a is equipped with second V type groove (not shown in the drawing), the opening of first V type groove 11a is set back to output shaft 3a, the opening of second V type groove is set to output shaft 3a, first V type groove 11a and second V type groove are same in structure, and the two are about the radial symmetry of main shaft 1a, first V type groove 11a and second V type groove form the cavity that contains steel ball together. The rotary drive force of motor output is transmitted to main shaft 1a after reduction by reduction mechanism, when main shaft 1a rotates, steel ball moves along first V type groove 11a, so that strike block 21a can be displaced along the axial direction of main shaft 1a, impact mechanism 2a drives output shaft 3a to output power outward through steel ball, and when impact tool impacts, first protrusion 211a provided with strike block 21a will circumferentially collide with second protrusion 31a provided with output shaft 3a.
[0003] The structure of the existing first V type groove 11a and second V type groove, the slope position of each point of the base line of the one-way channel of first V type groove 11a is invariable.
[0004] When the impact tool is in operation, the output shaft 3a is located below the main shaft 1a, for example, when strike block 21a moves upward along first V type groove 11a, if the speed is too large at this time, second V type groove is easy to hit first V type groove 11a through steel ball, or the end face of strike block 21a hits planet carrier 12a provided on main shaft 1a, the axial force generated by these collisions is transmitted to the hand through the shell of electric tool, the collision in the process is called as upper collision; when strike block 21a moves downward along first V type groove 11a, if the speed is too large at this time, it is easy to cause first protrusion 211a and second protrusion 31a to collide in the axial direction of main shaft 1a, the collision in the process is called as lower collision, the collision force is transmitted to the hand through the shell, which affects the hand feeling, also aggravates the wear of first protrusion 211a and second protrusion 31a, reduces the service life of electric tool.
[0005] In addition, the movement state of the impact block 21a is closely related to the application working condition. When the output shaft 3a is stuck, the rebound rate (rebound angular velocity and impact angular velocity) of the impact block 21a will suddenly increase, which causes the rotation angle and the circumferential displacement of the impact block 21a during rebound to increase, and the upper and lower impacts are prone to occur. Whether the sleeve of the impact wrench is stuck is related to the size and wear condition of the sleeve and the bolt. Through tests, it is found that the sleeve is easy to be stuck when M12 bolts and M24 bolts are fixed, and the sleeve is not easy to be stuck when M16 and M42 bolts are fixed. When the upper impact or the lower impact occurs due to the sticking, the existing V-shaped groove type impact system is difficult to avoid by adjusting the angle of the V-shaped groove. Generally, the spring force is increased to reduce the upper impact. However, the increase of the spring force will aggravate the lower impact (the collision between the first protrusion 211a and the second protrusion 31a) between the impact block 21a and the output shaft 3a, aggravate the wear of the impact block 21a and the output shaft 3a, and shorten the service life. Therefore, blindly increasing the spring force may cause other adverse impacts, and the problem cannot be better solved. Content of the utility model
[0006] Based on the above defects in the prior art, the purpose of the utility model is to provide an impact tool, which optimizes the baseline of the first groove of the main shaft to adjust the slope of the moving track of the steel ball, optimizes the movement process of the impact block, reduces the risk of upper and lower impacts of the impact block, and improves the use feeling and service life of the impact tool.
[0007] To this end, the utility model provides the following technical scheme.
[0008] The utility model provides an impact tool, which comprises:
[0009] a main shaft, which is provided with a first groove on the circumferential surface wall; the first groove is substantially V-shaped, and comprises a first extension groove and a second extension groove intersecting with each other, and the first extension groove and the second extension groove are symmetrical about the center axis of the main shaft;
[0010] an impact assembly, which comprises an impact block, a steel ball and an elastic member, the impact block is sleeved on the outer periphery of the main shaft; the inner side surface wall of the impact block is provided with a second groove, which is matched with the structure of the first groove one by one to jointly form a ball channel for accommodating the steel ball; the first groove, the second groove and the steel ball are matched to drive the main shaft to drive the impact block to rotate or impact;
[0011] wherein the baseline of the first extension groove at least comprises a first line segment and a second line segment which are sequentially distributed in the direction towards the V-shaped opening of the first extension groove, the slope of each point in the second line segment in the direction away from the first line segment gradually decreases, and the slope K m of the first line segment is greater than the maximum slope K n-max.
[0012] Optionally, the second line segment is a parabola.
[0013] Optionally, the first line segment is a straight line.
[0014] Optionally, the base line of the first extension groove further comprises a connecting line segment, the connecting line segment is a circular arc; the first line segment, the connecting line segment and the second line segment are sequentially connected.
[0015] The slope of each point of the connecting line segment in the direction away from the first line segment gradually decreases, K m The maximum slope of the connecting line segment K t-max > K n-max .
[0016] Optionally, the slope of the first line segment away from one end of the connecting line segment K m1 > 50°, the slope of the first line segment at the tangent position of the connecting line segment is less than 35°, the slope of the second line segment away from one end of the connecting line segment is K n-min , 25°> K n-min > 0°.
[0017] Optionally, the base line of the first extension groove is a circular arc line segment, the slope of each point of the base line in the direction towards the V-shaped opening gradually decreases.
[0018] Optionally, the end point slope of one end of the base line of the first extension groove is the maximum slope K s-max , and the end point slope of the other end is the minimum slope K s-min , wherein K s-max > 50°, 25°> K s-min > 0°.
[0019] Optionally, the second groove is substantially V-shaped; the groove structures of the matched second groove and the first groove are the same, and the V-shaped openings of the two are opposite.
[0020] Optionally, the main shaft is integrally formed with a planet carrier, one end of the elastic piece abuts against the planet carrier, and the other end abuts against the hitting block.
[0021] The utility model has the following technical effects:
[0022] The utility model provides a kind of impact tool, the baseline of the first recess of main shaft is optimized, to adjust the slope of the moving track of steel ball, optimize the movement process of impact block, reduce the risk of upper and lower impact of impact block, and, according to the different of actual application working condition, for example, sleeve and bolt are not easy to jam, the size of impact block resilience, system parameter requirement, to select the angle range of the tangent of the moving track of steel ball, and then adjust the axial displacement and axial movement speed of impact block, avoid the generation of undesirable collision, stabilize the output torque of impact tool, and then it can improve the use feeling and service life of impact tool. BRIEF DESCRIPTION OF DRAWINGS
[0023] Figure 1A It is the assembly structure diagram of main shaft, impact mechanism and output shaft in prior art;
[0024] Figure 1B It is the structure diagram of main shaft in prior art;
[0025] Figure 2 It is the structure section view of impact tool of the utility model;
[0026] Figure 3 It is the assembly three-dimensional structure diagram of main shaft, impact component and output shaft of the utility model;
[0027] Figure 4 It is the assembly structure side view of main shaft, impact component and output shaft of the utility model;
[0028] Figure 5 It is the assembly structure section view of main shaft, impact component and output shaft of the utility model;
[0029] Figure 6 It is the assembly structure explosion view of main shaft, impact component and output shaft in the first embodiment of the utility model;
[0030] Figure 7 It is the structure side view of main shaft in the first embodiment of the utility model
[0031] Figure 8 It is the structure side view of main shaft in the first embodiment of the utility model Figure Two ;
[0032] Figure 9 It is the structure diagram of baseline of the first recess in the first embodiment of the utility model;
[0033] Figure 10 It is the structure section view of impact block in the first embodiment of the utility model
[0034] Figure 11 It is the structure section view of impact block in the first embodiment of the utility modelFigure Two ;
[0035] Figure 12 Structure side view of the main shaft in the second embodiment of the utility model;
[0036] Figure 13 Structure schematic view of the baseline of the first recess in the second embodiment of the utility model;
[0037] Figure 14 Structure sectional view of the striking block in the second embodiment of the utility model.
[0038] Explanation of reference signs
[0039] 100, impact tool;
[0040] 1, main shaft; 11, first recess; 111, first extension groove; 1111, first line segment; 1112, second line segment; 1113, connecting line segment; 112, second extension groove; 12, planet carrier;
[0041] 2, impact assembly; 21, striking block; 211, second recess; 212, first protruding part; 22, steel ball; 23, elastic member;
[0042] 3, output shaft; 31, second protruding part;
[0043] 4, speed reduction mechanism;
[0044] 5, motor;
[0045] 1a, main shaft; 11a, first V-shaped groove; 12a, planet carrier; 2a, impact mechanism; 21a, striking block; 211a, first protruding block; 22a, spring; 3a, output shaft; 31a, second protruding block. DETAILED DESCRIPTION
[0046] In order to make the technical scheme and beneficial effects of the utility model more obvious and easy to understand, the following will be described in detail by way of listing specific embodiments. Unless otherwise defined, the technical and scientific terms used in this document have the same meaning as the technical and scientific terms in the technical field to which the present application belongs.
[0047] In the description of the utility model, unless otherwise explicitly limited, the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of simplified description of the utility model, and does not indicate that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, that is, cannot be understood as a limitation on the utility model.
[0048] In the utility model, the terms "first" and "second" are only for the purpose of clear description, and cannot be understood as the relative importance of the indicated features or the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly include at least one of the features. In the description of the utility model, the meaning of "multiple" is at least two; the meaning of "several" is at least one; except for explicit limitation.
[0049] In the utility model, unless otherwise explicitly limited, the terms "mounting", "connection", "connection", "fixing", "setting" and the like should be understood broadly. For example, "connection" can be fixed connection, detachable connection or integral molding; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through intermediate medium, can also be the communication or interaction relationship between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.
[0050] In the utility model, unless otherwise explicitly limited, the first feature "on", "over", "above" and "upper", "lower", "under", "below" or "below" of the second feature can be that the first feature and the second feature are in direct contact, or the first feature and the second feature are indirectly contacted through intermediate medium. Moreover, the first feature "over", "above" and "upper" of the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "below" of the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.
[0051] The "upper" and "lower" mentioned in the utility model are based on the mark in Figure 1A 、 Figure 1B 、 Figures 2 to 5 、 Figures 7 to 14 .
[0052] The following will be described according toFigures 2 to 14 The impact tool is described in detail.
[0053] In the embodiment, as shown in Figures 2 to 6 The impact tool 100 includes a main shaft 1, an impact assembly 2, an output shaft 3, a speed reduction mechanism 4, and a motor 5. The speed reduction mechanism 4 is a planetary gear train. The motor 5 outputs rotary power, which is transmitted to the main shaft 1 after being reduced by the speed reduction mechanism 4. The main shaft 1 drives the output shaft 3 to move the tool head (such as a bit or a sleeve) through the impact assembly 2 to perform work.
[0054] It should be understood that, for the sake of illustration, as shown in Figure 2 The output shaft 3 is below the main shaft 1 when the impact tool 100 is in a working state.
[0055] As shown in Figure 6 , Figure 7 and Figure 12 The circumferential wall of the main shaft 1 is provided with a first groove 11. The first groove 11 is substantially V-shaped. The first groove 11 includes a first extension groove 111 and a second extension groove 112 that intersect. The first extension groove 111 and the second extension groove 112 are symmetrical about the center axis of the main shaft 1.
[0056] As shown in Figure 5 , Figure 6 , Figure 11 and Figure 12 The impact assembly 2 includes a striker 21, a steel ball 22, and an elastic member 23. The striker 21 is sleeved on the outer periphery of the main shaft 1. The inner side wall of the striker 21 is provided with a second groove 211. The second groove 211 matches the structure of the first groove 11 one by one to form a ball channel for accommodating the steel ball 22.
[0057] When the load force borne by the output shaft 3 does not exceed the preset value, at this time, the main shaft 1 pushes the second groove 211 through the steel ball 22 to drive the striker 21 to rotate. The striker 21 outputs a rotary driving force to the output shaft 3, and then the output shaft 3 drives the tool head to rotate.
[0058] When the load force borne by the output shaft 3 exceeds the preset value, the rotation of the output shaft 3 is blocked. As shown in Figure 4 The first protruding part 212 of the striker 21 impacts the second protruding part 31 of the output shaft 3 circumferentially to impact. Specifically, when the striker 21 circumferentially collides with the output shaft 3, the striker 21 rebounds. At this time, the angular velocity of the striker 21 is negative, and the axial velocity is positive. Figure 5As shown, under the cooperation of the first groove 11, the second groove 211 and the steel ball 22, the impact block 21 moves upward and reverses rotation, until the angular velocity of the impact block 21 is greater than 0, the impact block 21 becomes positive rotation, in this process, the impact block 21 compresses the elastic member 23, when the axial velocity of the impact block 21 is reduced to equal to 0, the displacement value of the upward movement of the impact block 21 reaches the maximum value, the steel ball 22 moves to the top of the first groove 11, if the axial velocity of the impact block 21 fails to reduce to 0 and the steel ball 22 moves to the top of the first groove 11, the impact block 21 will hit the first groove 11 of the main shaft 1 through the steel ball 22. Then, under the elastic force provided by the elastic member 23, the impact block 21 rotates and moves downward along the first groove 11, so that the rotation of the main shaft 1 can drive the impact block 21 to impact the output shaft 3 periodically in the rotation direction, under the impact force, the output shaft 3 rotates a certain angle and then stops rotating again under the load force, and the above process is repeated to realize continuous impact work, but in the process of the downward movement of the impact block 21, if the first protruding part 212 moves downward to the same horizontal plane as the upper surface of the second protruding part 31, and the first protruding part 212 has not passed the second protruding part 31, the first protruding part 212 will downwardly collide with the second protruding part 31 to generate a downward collision. It should be understood that the operating principle of the impact tool can refer to any existing impact wrench or impact driver.
[0059] As shown in Figure 9 and Figure 13 , the baseline of the first extension groove 111 at least includes a first line segment 1111 and a second line segment 1112, the first line segment 1111 and the second line segment 1112 are sequentially distributed in the direction towards the V-shaped opening of the first extension groove 111, the direction of the V-shaped opening is Figure 7 and Figure 12 upward direction, the slope of the second line segment 1112 gradually decreases at each point in the direction away from the first line segment 1111, and the slope of the point closest to the first line segment 1111 of the second line segment 1112 is the maximum, K n-max , the slope K m of the first line segment 1111 is greater than the maximum slope K n-max of the second line segment 1112.
[0060] The technical scheme has the advantages that the baseline of the first groove 11 is optimized to adjust the slope of each point of the moving track of the steel ball 22, thereby optimizing the movement process of the striking block 21, reducing the risk of upward and downward impacts on the striking block 21, and according to different actual application conditions, for example, according to whether the sleeve and the bolt are prone to be stuck, the size of the striking block rebound rate, and system parameter requirements, the angle range of the tangent of the moving track of the steel ball 22 is selected, thereby adjusting the axial displacement and axial movement speed of the striking block 21, avoiding the generation of undesirable impacts, stabilizing the output torque of the impact tool 100, thereby being capable of improving the use feeling and service life of the impact tool 100.
[0061] It should be understood that the second extension groove 112 is symmetrically arranged with the first extension groove 111, the structure, shape and size of the second extension groove 112 are determined according to the first extension groove 111, and the stress condition of the striking block 21 when the steel ball 22 moves in the second extension groove 112 can refer to the stress condition of the striking block 21 when the steel ball 22 moves in the first extension groove 111, which will not be described here.
[0062] Specifically, in the process of rotation of the main shaft 1, the striking block 21 is subjected to an acting force including an axial acting force F x and a rotating acting force F θ The relationship between the acting force of the striking block 21 and the slope of the baseline of the first extension groove 111 is as follows:
[0063]
[0064]
[0065] F x =F 合 cosα (3)
[0066] F θ =F 合 sinα (4)
[0067] Wherein, F 合 is the resultant force of the steel ball on the striking block, α is the tangent angle of the track, F 弹 is the elastic force of the elastic member 23, m is the mass of the striking block, J is the rotational inertia of the striking block, L is the rotating force arm of the striking block, is the axial displacement acceleration of the striking block, is the rotational angle acceleration of the striking block. It can be known from formula (3) and formula (4) that the smaller the slope of a point of the baseline of the first extension groove 111, the greater the proportion of the axial acting force F x of the striking block 21, and the smaller the proportion of the rotating acting force F θ of the striking block 21.
[0068] In the prior art, for example,Figure 1B As shown, the slope of each point of the baseline of the one-way channel of the first V-shaped groove 11a is constant, that is, the track tangent angle α of the one-way channel is constant, F x and F θ The proportion is constant, and it is easy to hit or hit down when hitting, and it is difficult to match various application conditions.
[0069] In the present scheme, as shown in Figure 4 , Figure 5 , Figure 9 and Figure 13 As shown, when the percussion block 21 impacts the output shaft 3 circumferentially, the percussion block 21 will rebound and move upward, and since K m >K n-max , the α value corresponding to the first line segment 1111 is greater than the α value corresponding to the second line segment 1112, and during the upward movement of the steel ball 22 along the first line segment 1111, since the α value corresponding to the first line segment 1111 is larger, the percussion block 21 can obtain greater axial displacement under smaller rebound rotation angle, so that the elastic force of the elastic member 23 acting on the percussion block 21 increases rapidly, making the downward resultant force acting on the percussion block 21 larger, which can reduce the axial speed of the upward movement of the percussion block 21, thereby reducing the risk of the percussion block 21 upwardly colliding with the first groove 11 of the main shaft 1 through the steel ball 22, and compared with the structure of the first V-shaped groove 11a in the prior art, the present scheme can also reduce the upward movement stroke of the percussion block 21, thereby reducing the risk of the upper end surface of the percussion block 21 upwardly colliding with the circumferentially outwardly convex portion (planetary carrier 12) of the main shaft 1. In addition, since the α value corresponding to the first line segment 1111 is larger, the rotational force F θ acting on the percussion block 21 is larger, the percussion block 21 has a larger angular acceleration (angular acceleration > 0), and the rotational angular velocity of the percussion block 21 can rapidly increase from a negative value to 0, so that the percussion block 21 rapidly changes from negative rotation to positive rotation, thereby reducing the rebound rotation angle of the percussion block 21, so that the first protruding portion 212 of the percussion block 21 is more easily over the second protruding portion 31 of the output shaft 3, thereby reducing the risk of the first protruding portion 212 downwardly colliding with the second protruding portion 31 when the percussion block 21 moves downward.
[0070] When the percussion block 21 moves downward, since the α value corresponding to the second line segment 1112 is smaller, the axial force F x occupies a larger proportion, and the downward resultant force acting on the percussion block 21 is smaller, so that during the downward movement of the steel ball 22 along the second line segment 1112, the downward movement speed of the percussion block 21 is smaller, the downward movement time is increased, and the percussion block 21 has more time to rotate positively at a high position (rotational angular velocity > 0), so that the first protruding portion 212 is more easily over the second protruding portion 31 of the output shaft 3, thereby reducing the risk of the first protruding portion 212 downwardly colliding with the second protruding portion 31 when the percussion block 21 moves downward.
[0071] In an embodiment, as shown in Figure 10 and Figure 14 , the second groove 211 is substantially V-shaped; the second groove 211 and the first groove 11 are symmetrical about the radial plane of the main shaft 1, and the V-shaped openings of the two are opposite, and the baseline of the second groove 211 is optimized accordingly. Of course, the structure of the second groove 211 is not limited to being the same as that of the first groove 11.
[0072] In an embodiment, as shown in Figure 8 , the number of the first grooves 11 is two, and the two first grooves 11 are symmetrically arranged about the central axis of the main shaft 1, as shown in Figure 5 , Figure 6 and Figure 11 , the number of the second grooves 211 and the steel balls 22 is two, and the first grooves 11, the second grooves 211 and the steel balls 22 are one-to-one matched.
[0073] In an embodiment, as shown in Figure 2 , Figure 3 and Figure 6 , the main shaft 1 is integrally formed with the planet carrier 12, and the planet wheel of the speed reduction mechanism 4 is installed on the planet carrier 12. One end of the elastic member 23 abuts against the planet carrier 12, and the other end abuts against the striking block 21. When the striking block 21 moves upward, the elastic member 23 is compressed, and when the striking block 21 moves downward, the elastic member 23 provides power for the downward movement of the striking block 21.
[0074] In an embodiment, the elastic member 23 is a spring, which is simple in structure.
[0075] First embodiment
[0076] The impact tool of the first embodiment of the utility model will be described in detail below. Figures 7 to 11
[0077] In this embodiment, as shown in Figure 7 and Figure 9 , the second line segment 1112 is a parabola, and the track of the parabola has no radius limit, so that the trajectory of the movement of the striking block 21 can be designed more flexibly according to different working conditions. As shown in Figure 7 and Figure 10 , the second groove 211 and the first groove 11 are symmetrically arranged about the radial plane of the main shaft 1.
[0078] In an embodiment, as shown in Figure 9 , the first line segment 1111 is a straight line, which is convenient for processing.
[0079] Further, as shown in Figure 9 As shown, the baseline of the first extension groove 111 also includes a connecting line segment 1113, which is an arc. The first line segment 1111, the connecting line segment 1113, and the second line segment 1112 are connected sequentially. The connecting line segment 1113 acts as a transition between the first line segment 1111 and the second line segment 1112, which facilitates the smooth movement of the steel ball 22 along the first groove 11. The slope of the connecting line segment 1113 gradually decreases at each point along the direction away from the first line segment 1111, and the slope is the largest at the point of the connecting line segment 1113 closest to the first line segment 1111, which is K. t-max K m > The maximum slope K of connecting line segment 1113 t-max >K n-max Thus, when the striking block 21 rebounds and moves upward due to the circumferential impact on the output shaft 3, the α values corresponding to the first line segment 1111 and the connecting line segment 1113 are both relatively large. The striking block 21 can obtain a larger axial displacement under a small rebound rotation angle, thereby reducing the risk of the striking block 21 hitting the upper and lower parts of the shaft.
[0080] Furthermore, such as Figure 9 As shown, in order to just reduce the risk of collision with the upper and lower parts of the striking block 21, the slope K of the end of the first line segment 1111 away from the connecting line segment 1113 is... m1 >50°, the slope at the point where the first line segment 1111 is tangent to the connecting line segment 1113 is less than 35°, and the slope of the end of the second line segment 1112 furthest from the connecting line segment 1113 is K. n-min 25°>K n-min >0°.
[0081] Second Implementation Method
[0082] The following is based on Figures 12 to 14 The impact tool of the second embodiment of this utility model is described in detail.
[0083] In this embodiment, such as Figure 12 and Figure 13 As shown, the baseline of the first extension groove 111 is an arc segment. The first segment 1111 and the second segment 1112 form two segments of the arc, and the slope of the baseline gradually decreases at each point along the direction towards its V-shaped opening. The arc-shaped track eliminates the need for transitions between straight and parabolic segments, resulting in a smoother track transition. Figure 12 and Figure 14 As shown, the second groove 211 and the first groove 11 are arranged symmetrically about the radial plane of the main shaft 1.
[0084] Furthermore, such as Figure 13 As shown, in order to just reduce the risk of impacting the upper and lower parts of the striking block 21, the slope of one end of the baseline of the first extension groove 111 is the maximum slope K. s-max, the end point of the other end has a minimum slope K s-min wherein K s-max > 50°, 25° > K s-min > 0°.
[0085] It should be understood that the baseline optimization of the first recess 11 provided by the present application is not limited to the specific schemes listed in the first and second embodiments, such as, but not limited to, the baseline of the first extension groove 111 is composed of a track formed by a first line segment 1111 in the form of a circular arc and a second line segment 1112 in the form of a parabola, to match more application conditions and impact systems with different parameters.
[0086] It should be understood that the above embodiments are exemplary and are not intended to include all possible embodiments included in the claims. Various modifications and changes can also be made on the basis of the above embodiments without departing from the scope of the present disclosure. Similarly, any combination of the technical features of the above embodiments can also be made to form additional embodiments of the present application that may not have been explicitly described. Therefore, the above embodiments only express several embodiments of the present application, and do not limit the protection scope of the present application patent.
Claims
1. An impact tool characterized by comprising: The impact tool (100) comprises: a main shaft (1) having a first groove (11) formed on a circumferential wall thereof; the first groove (11) is substantially V-shaped and comprises a first extension groove (111) and a second extension groove (112) intersecting with each other, the first extension groove (111) and the second extension groove (112) being symmetrical about a central axis of the main shaft (1); an impact assembly (2) comprising a striking block (21), a steel ball (22) and an elastic member (23), the striking block (21) being sleeved on an outer periphery of the main shaft (1); an inner side wall of the striking block (21) is provided with a second groove (211) matching the structure of the first groove (11) one by one to jointly form a ball channel for accommodating the steel ball (22); the first groove (11), the second groove (211) and the steel ball (22) cooperate to enable the main shaft (1) to drive the striking block (21) to perform a rotating motion or an impact motion; The baseline of the first extending groove (111) at least comprises a first line segment (1111) and a second line segment (1112) distributed in sequence in the direction towards the V-shaped opening of the first extending groove (111), the slope of each point in the direction away from the first line segment (1111) of the second line segment (1112) gradually decreases, the slope K m of the first line segment (1111) is greater than the maximum slope K n-max of the second line segment (1112).
2. The impact tool according to claim 1, characterized by the second line segment (1112) is a parabola.
3. The impact tool according to claim 2, wherein the first line segment (1111) is a straight line.
4. The impact tool according to claim 3, characterized by the base line of the first extension groove (111) further comprises a connecting line segment (1113), the connecting line segment (1113) being a circular arc; the first line segment (1111), the connecting line segment (1113) and the second line segment (1112) are sequentially connected; The slope of the connecting line segment (1113) gradually decreases at points along a direction away from the first line segment (1111), K m The maximum slope K of the connecting line segment (1113) t-max K n-max .
5. The impact tool according to claim 4, wherein the slope K of the first line segment (1111) away from the end of the connecting line segment (1113) m1 > 50°, the slope of the first line segment (1111) at the point of tangency with the connecting line segment (1113) is less than 35°, and the slope K of the second line segment (1112) away from the end of the connecting line segment (1113) n-min is 25° > K n-min > 0°.
6. The impact tool according to claim 1, wherein the base line of the first extension groove (111) is a circular arc segment, and the slope of each point of the base line in the direction towards the V-shaped opening gradually decreases.
7. The impact tool according to claim 6, characterized by The end point of one end of the base line of the first extension groove (111) has a maximum slope K s-max , and the end point of the other end has a minimum slope K s-min , wherein K s-max > 50°, 25° > K s-min > 0°.
8. The impact tool according to any one of claims 1 to 7, characterized by, the second groove (211) is substantially V-shaped; the second groove (211) and the first groove (11) are both the same in groove structure, and the V-shaped openings of the two are opposite.
9. The impact tool according to any one of claims 1 to 7, characterized by, the main shaft (1) is integrally formed with a planet carrier (12), one end of the elastic member (23) abutting against the planet carrier (12) and the other end abutting against the striking block (21).