An impact wrench

Abstract

This invention discloses an impact wrench, belonging to the field of power tool technology. The impact wrench includes an output shaft, a socket, and a locking structure. The output shaft extends along a first axis a and is configured to rotate about the first axis a. The output shaft includes a square shaft, and the socket is detachably fitted onto the square shaft. A stepped portion is provided on the free end of the square shaft, comprising a sequentially connected annular stepped surface, a cylindrical surface, and an end face. The locking structure includes an elastic deformable body, which is coaxially locked onto the cylindrical surface. At least a portion of the winding diameter of the elastic deformable body is greater than the maximum diagonal of any cross-section on the output shaft, so that when the socket is configured to be fitted onto the square shaft, the elastic deformable body can elastically press against the inner wall surface of the socket. This impact wrench features high coaxiality between the elastic deformable body and the output shaft, reduces the difficulty of assembling and disassembling the socket and the output shaft, has high reliability and durability in the locking structure, and provides high structural strength for the output shaft.

Description

Technical Field

[0001] This invention relates to the field of power tool technology, and more particularly to an impact wrench. Background Technology

[0002] An impact wrench is a common power tool used for disassembly, installation, and drilling. Impact wrenches typically include a high-speed rotating output shaft. When using an impact wrench to remove bolts from scaffolding or vehicles, the output shaft must be used with a socket wrench, which must be locked onto the output shaft.

[0003] Existing locking structures for securing the sleeve to the output shaft are mostly C-ring or pin structures. However, C-ring structures have drawbacks such as easy detachment and failure, easy deformation and jamming, difficulty in disassembling and assembling the sleeve, and deformation and functional failure after long-term use. Pin structures, on the other hand, require drilling holes in the square shaft portion of the output shaft during installation, which not only damages the cross-sectional structure that transmits torque on the output shaft and reduces its structural strength, but also makes it prone to early strength deficiency and breakage, and limits the maximum output torque of the impact wrench.

[0004] Therefore, how to develop an impact wrench that can overcome the above-mentioned defects is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide an impact wrench that is highly reliable, durable, has a long service life, and is easy to assemble and disassemble.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] An impact wrench includes: an output shaft extending along a first axis a and configured to rotate about the first axis a, the output shaft comprising a square shaft; a sleeve detachably fitted onto the square shaft, the free end of the square shaft having a stepped portion comprising a sequentially connected annular stepped surface, a cylindrical surface, and an end face; the impact wrench further includes a locking structure comprising an elastic deformable body coaxially locked onto the cylindrical surface, at least a portion of the winding diameter of the elastic deformable body being greater than the maximum diagonal of any cross-section of the output shaft perpendicular to the first axis a, such that when the sleeve is configured to be fitted onto the square shaft, the elastic deformable body can elastically press against the inner wall surface of the sleeve.

[0008] Preferably, one end of the elastic deformable body abuts against the annular step surface; the impact wrench also includes a stop structure, which is detachably connected to the step portion and has a limiting stop surface that stops the other end of the elastic deformable body.

[0009] Preferably, a mounting hole is formed on the end face along the first axis a; the stop structure includes a limiting plate and a connecting post connected coaxially, the size of the limiting plate is larger than the size of the end face, and the end of the connecting post away from the limiting plate can be inserted into the mounting hole.

[0010] Preferably, a threaded hole is provided on the end face along the first axis a; the stop structure includes a fixing ring and a fixing member, the size of the fixing ring is larger than the size of the end face, the fixing ring is provided with a countersunk hole, the cap of the fixing member is placed in the countersunk hole, and the screw of the fixing member passes through the countersunk hole and is threaded into the threaded hole.

[0011] Preferably, a threaded hole is formed on the end face along the first axis a; the stop structure includes a limiting plate and a stud connected coaxially, the size of the limiting plate is larger than the size of the end face, and the stud is threadedly connected in the threaded hole.

[0012] Preferably, a mounting post is protruding along the first axis a on the end face, and an annular groove is provided on the end of the mounting post away from the end face; the stop structure includes a fixing ring and a first retaining ring, the fixing ring is sleeved on the mounting post, and the outer diameter of the fixing ring is larger than the size of the end face, the annular groove and the end face are located on both sides of the fixing ring, the first retaining ring is engaged in the annular groove, and the outer diameter of the first retaining ring is larger than the inner diameter of the fixing ring.

[0013] Preferably, an annular limiting groove is provided on the columnar surface, and the annular limiting groove and the annular stepped surface are located on both sides of the elastic deformable body; the stop structure includes a second retaining ring, which is engaged with the annular limiting groove and abuts against the elastic deformable body.

[0014] Preferably, the locking structure further includes an elastic ring, which is sleeved on the cylindrical surface, and the elastic deformable body is sleeved on the outer wall surface of the elastic ring.

[0015] Preferably, the elastic deformable body includes a locking spring, which includes an inner ring and a spiral outer ring connected to the inner ring. The inner ring is sleeved and clamped to the outer wall surface of the elastic ring, and the outermost ring of the spiral outer ring protrudes from the outer wall surface of the output shaft and can abut against the inner wall surface of the sleeve.

[0016] Preferably, the elastic deformable body includes a C-shaped spring ring, which is sleeved and clamped to the outer wall surface of the elastic ring. The outer wall surface of the C-shaped spring ring protrudes from the outer wall surface of the output shaft and can elastically abut against the inner wall surface of the sleeve.

[0017] Preferably, a limiting structure is provided between the fixing ring and the end face.

[0018] An impact wrench includes: an output shaft extending along a first axis a and configured to rotate about the first axis a, the output shaft comprising a square shaft; a sleeve detachably sleeved on the square shaft, the free end of the square shaft having a stepped portion comprising an annular stepped surface, a cylindrical surface, and an end face connected in sequence; the impact wrench further includes a locking structure comprising an elastic deformable body coaxially locked onto the cylindrical surface; the impact wrench further includes a stop structure detachably connected to the stepped portion and having a limiting stop surface that stops the other end of the elastic deformable body.

[0019] The beneficial effects of this invention are:

[0020] This invention provides an impact wrench comprising an output shaft, a sleeve, and a locking structure. The output shaft extends along a first axis a and is configured to rotate about the first axis a. The output shaft includes a square shaft, and the sleeve is detachably fitted onto the square shaft. A stepped portion is provided at the free end of the square shaft, comprising a sequentially connected annular stepped surface, a cylindrical surface, and an end face. The locking structure includes an elastic deformable body, which is coaxially locked and fitted onto the cylindrical surface. At least a portion of the rotation diameter of the elastic deformable body is greater than the maximum diagonal of any cross-section of the output shaft perpendicular to the first axis a, so that when the sleeve is fitted onto the square shaft, the elastic deformable body can elastically press against the inner wall of the sleeve. This impact wrench, by making at least a portion of the rotation diameter of the elastic deformable body greater than the maximum diagonal of any cross-section of the output shaft perpendicular to the first axis a, ensures that a portion of the elastic deformable body contacts the sleeve. Consequently, when the elastic deformable body undergoes equal deformation, the contact force is smaller. The locking structure is less prone to failure during long-term use, exhibiting high reliability and durability. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and first type of stop structure of the impact wrench provided in Embodiment 1 of the present invention;

[0022] Figure 2 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and second stop structure of the impact wrench provided in Embodiment 1 of the present invention from a certain perspective.

[0023] Figure 3 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and second stop structure of the impact wrench provided in Embodiment 1 of the present invention from another perspective.

[0024] Figure 4 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and third type of stop structure of the impact wrench provided in Embodiment 1 of the present invention;

[0025] Figure 5 This is a schematic diagram of the output shaft, sleeve, elastic ring, C-shaped spring ring, and first type of stop structure of the impact wrench provided in Embodiment 1 of the present invention;

[0026] Figure 6 This is a schematic diagram of the output shaft, socket, elastic ring, C-shaped spring ring, and second type of stop structure of the impact wrench provided in Embodiment 1 of the present invention from a certain perspective.

[0027] Figure 7 This is a schematic diagram of the output shaft, socket, elastic ring, C-shaped spring ring, and second type of stop structure of the impact wrench provided in Embodiment 1 of the present invention from another perspective.

[0028] Figure 8 This is a schematic diagram of the output shaft, sleeve, elastic ring, C-shaped spring ring, and third type of stop structure of the impact wrench provided in Embodiment 1 of the present invention;

[0029] Figure 9 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and fourth stop structure of the impact wrench provided in Embodiment 2 of the present invention from a certain perspective.

[0030] Figure 10 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and fourth stop structure of the impact wrench provided in Embodiment 2 of the present invention from another perspective.

[0031] Figure 11 This is a schematic diagram of the output shaft, sleeve, elastic ring, locking spring, and fifth stop structure of the impact wrench provided in Embodiment 2 of the present invention;

[0032] Figure 12 This is a schematic diagram of the output shaft, sleeve, elastic ring, C-shaped spring ring, and fourth type of stop structure of the impact wrench provided in Embodiment 2 of the present invention from a certain perspective.

[0033] Figure 13 This is a schematic diagram of the output shaft, sleeve, elastic ring, C-shaped spring ring, and fourth type of stop structure of the impact wrench provided in Embodiment 2 of the present invention from another perspective.

[0034] Figure 14 This is a schematic diagram of the output shaft, sleeve, elastic ring, C-shaped spring ring, and fifth gear structure of the impact wrench provided in Embodiment 2 of the present invention.

[0035] In the picture:

[0036] 100. Output shaft; 110. Stepped section; 111. Annular stepped surface; 112. Columnar surface; 113. End face; 114. Mounting hole; 115. Limiting groove; 116. Threaded hole; 117. Mounting post; 118. Annular groove; 119. Annular limiting groove;

[0037] 120. Cylindrical shaft; 130. Square shaft;

[0038] 200. Locking structure; 210. Elastic ring; 220. Locking spring; 230. C-shaped spring ring;

[0039] 300, Gear structure; 310, Limiting plate; 320, Connecting post; 330, Stud; 340, Retaining ring; 341, Limiting block; 350, Fixing component; 360, First retaining ring; 370, Second retaining ring. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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 the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0043] Example 1:

[0044] This embodiment provides an impact wrench that can be used for disassembly, installation, and drilling. The impact wrench includes a housing, a motor, a battery, a transmission mechanism, and an output shaft 100. Specifically, the motor, battery, and transmission mechanism are all located inside the housing. The battery powers the motor, the motor shaft is drive-connected to the input end of the transmission mechanism, and the output end of the transmission mechanism is drive-connected to the output shaft 100. At least a portion of the output shaft 100 is located outside the housing and extends along a first axis a. Driven by the motor and transmission mechanism, the output shaft 100 can rotate around the first axis a. The housing, motor, battery, and transmission mechanism are all prior art and will not be described in detail here.

[0045] More specifically, the output shaft 100 includes a cylindrical shaft 120 and a square shaft 130 connected to each other. The square shaft 130 is located at the free end of the output shaft 100 away from the transmission mechanism. As its name suggests, the square shaft 130 is a columnar structure with four planes on its outer wall surface. Any two adjacent planes are perpendicular to each other, and any opposite planes are parallel to each other. The impact wrench also includes a socket, which is detachably connected to the square shaft 130. By changing different sockets, the impact wrench can perform different functions.

[0046] In this embodiment, to achieve a stable connection between the square shaft 130 and the sleeve, ensuring sufficient locking force between the square shaft 130 and the sleeve, and to guarantee reliable connection even after multiple installations and disassemblies of the sleeve and the square shaft 130, while maintaining relatively easy assembly and disassembly, as follows... Figures 1 to 8 As shown, a stepped portion 110 is provided on the free end of the square shaft 130. The stepped portion 110 includes an annular stepped surface 111, a cylindrical surface 112, and an end face 113 connected in sequence. The annular stepped surface 111 is a horizontal plane, and the cylindrical surface 112 is perpendicular to the annular stepped surface 111, forming an annular groove with a vertical cross-section of L between them. The end face 113 is parallel to the annular stepped surface 111, and this end face 113 is also the end plane of the end of the output shaft 100 away from the transmission mechanism. The impact wrench also includes a locking structure 200, which includes an elastic deformable body. The elastic deformable body is coaxially locked and sleeved on the cylindrical surface 112. The rotation diameter of at least part of the elastic deformable body is greater than the maximum diagonal of any cross-section of the output shaft 100 perpendicular to the first axis a, so that when the sleeve is sleeved on the square shaft 130, the elastic deformable body can elastically press against the inner wall surface of the sleeve.

[0047] Because the elastic deformable body is made of elastic material, it can deform under external force, especially when torsion, its outer diameter can change significantly. Therefore, when installing the sleeve onto the square shaft 130, the elastic deformable body can be appropriately compressed by the mutual compression between the inner wall of the sleeve and the outer wall of the square shaft 130 by rotating the sleeve, thus making it easier to install the sleeve onto the square shaft 130. After assembly, the elastic deformable body tends to return to its original shape. This tendency causes the elastic deformable body to elastically press against the inner wall of the sleeve, thus allowing the sleeve to be stably assembled onto the square shaft 130. When it is necessary to disassemble the sleeve, the elastic deformable body can be subjected to force by rotating the sleeve to appropriately reduce the size of the elastic deformable body again, thus allowing the sleeve to be easily detached from the square shaft 130.

[0048] This impact wrench makes at least part of the rotation diameter of the elastic deformable body greater than the maximum diagonal of any cross section of the output shaft 100 perpendicular to the first axis a, thereby making part of the structure of the elastic deformable body contact the sleeve. As a result, the contact force is smaller when the elastic deformable body undergoes the same deformation. The locking structure 200 is not easy to fail during long-term use, and has high reliability and good durability.

[0049] To ensure the coaxiality of the elastic deformable body with the square shaft 130, such as Figures 1 to 8 As shown, the impact wrench also includes an elastic ring 210. The elastic ring 210 is a circular ring structure made of elastic material, capable of appropriate deformation under external force. The inner diameter of the elastic ring 210 is slightly smaller than the diameter of the cylindrical surface 112, and the outer diameter of the elastic ring 210 is smaller than the length of the longest diagonal on the square shaft 130. The elastic ring 210 is fitted onto the cylindrical surface 112, and the elastic deformable body is fitted onto the outer wall surface of the elastic ring 210.

[0050] Since the inner diameter of the elastic ring 210 is slightly smaller than the diameter of the cylindrical surface 112, it can be ensured that the elastic ring 210 can be fitted onto the cylindrical surface 112 and tightened onto the cylindrical surface 112 under the action of external force, so as to ensure that the elastic ring 210 can be stably fitted onto the stepped portion 110, thereby ensuring that the elastic ring 210 and the square shaft 130 have good coaxiality, and further ensuring that the elastic deformable body fitted onto the elastic ring 210 and the square shaft 130 have good coaxiality.

[0051] Optionally, in this embodiment, as Figures 1 to 4As shown, the elastic deformable body includes a locking spring 220, which includes an inner ring and a spiral outer ring connected to the inner ring. The inner ring is sleeved and clamped onto the outer wall surface of the elastic ring 210. The outermost ring of the spiral outer ring protrudes from the outer wall surface of the output shaft 100 and can abut against the inner wall surface of the sleeve. Further optionally, in this embodiment, only one spiral outer ring is included, and the spiral outer ring and the inner ring are not located at the same level. The inner ring is located near the end face 113, and the outer ring is located near the annular step surface 111.

[0052] During the installation or removal of the sleeve, the locking spring 220 experiences radial compression at its helical section in the middle section, expanding outwards from both the start and end points. This reduces the maximum diameter of the spring, allowing the sleeve to be easily assembled and disassembled. By setting the elastic deformable body as a two-turn wound irregular spring, the diameter of each turn is smaller, resulting in a lower elastic coefficient. During the same deformation process, the contact force between the irregular spring and the sleeve is smaller, and the pressure on the structural surface is less, making it less prone to failure. Furthermore, according to the spring torque calculation formula and fatigue life calculation, the irregular spring with a reduced elastic coefficient K value is more durable and reliable.

[0053] When the elastic deformable body is a locking spring 220, in order to achieve axial limiting of the locking spring 220 and prevent the locking spring 220 from detaching from the free end of the step portion 110, one end of the elastic deformable body is abutted on the annular step surface 111. The impact wrench also includes a stop structure 300, which is detachably connected to the step portion 110, specifically connected to the end face 113, and has a limiting stop surface that stops the other end of the elastic deformable body.

[0054] Optionally, such as Figure 1 As shown, the shift structure 300 includes a limiting plate 310 and a connecting post 320 coaxially connected. The size of the limiting plate 310 is larger than the size of the end face 113. A mounting hole 114 is provided on the end face 113 along the first axis a. The end of the connecting post 320 away from the limiting plate 310 can be inserted into the mounting hole 114. An interference fit can be used to achieve a stable connection between the connecting post 320 and the mounting hole 114. Since the size of the limiting plate 310 is larger than the size of the end face 113, the bottom surface of the limiting plate 310 can prevent the elastic ring 210 and the locking spring 220 from disengaging from the free end of the square shaft 130 from the output shaft 100, thereby stably connecting the elastic ring 210 and the locking spring 220 to the columnar surface 112 of the stepped portion 110 of the square shaft 130.

[0055] Of course, in addition to the structure described above, the gear shift structure 300 can also be as follows: Figure 2 and Figure 3As shown, the stop structure 300 may include a retaining ring 340 and a fixing member 350. The size of the retaining ring 340 is larger than the size of the end face 113. The retaining ring 340 is provided with a countersunk hole. The cap of the fixing member 350 is placed in the countersunk hole. A threaded hole 116 is provided on the end face 113 along the first axis a. The screw of the fixing member 350 passes through the countersunk hole and is threaded into the threaded hole 116. This stop structure 300 can achieve a stable connection between the fixing member 350 and the square shaft 130 by using a threaded connection, thereby stably connecting the retaining ring 340 to the square shaft 130. Moreover, since the size of the retaining ring 340 is larger than the size of the end face 113, the bottom surface of the retaining ring 340 can prevent the elastic ring 210 and the locking spring 220 from disengaging from the free end of the square shaft 130 from the output shaft 100, thereby stably connecting the elastic ring 210 and the locking spring 220 to the columnar surface 112 of the stepped portion 110 of the square shaft 130. In addition, the countersunk hole on the retaining ring 340 can conceal the nut of the fastener 350, thereby improving the aesthetics and preventing the exposed nut from scratching the sleeve.

[0056] Optionally, to prevent the fixed ring 340 from rotating, a limiting structure is provided between the fixed ring 340 and the end face 113. Specifically, the limiting structure consists of a limiting block 341 and a limiting groove 115. One of the limiting block 341 and the limiting groove 115 is disposed on the annular surface of the fixed ring 340 near the end face 113, and the other is disposed on the end face 113. The limiting block 341 and the limiting groove 115 are engaged, thereby limiting the fixed ring 340 and preventing the fixed ring 340 from rotating around the first axis a.

[0057] Of course, in addition to the structure described above, the gear shift structure 300 can also be as follows: Figure 4 As shown, the stop structure 300 includes a limiting plate 310 and a stud 330 coaxially connected. The size of the limiting plate 310 is larger than the size of the end face 113. A threaded hole 116 is provided on the end face 113 along the first axis a, and the stud 330 is threaded into the threaded hole 116. This stop structure 300 achieves a stable connection between the stud 330 and the square shaft 130 through the threaded connection, thereby stably connecting the limiting plate 310 to the square shaft 130. Since the size of the limiting plate 310 is larger than the size of the end face 113, the lower bottom surface of the limiting plate 310 can prevent the elastic ring 210 and the locking spring 220 from disengaging from the free end of the square shaft 130 from the output shaft 100, thereby stably connecting the elastic ring 210 and the locking spring 220 to the cylindrical surface 112 of the stepped portion 110 of the square shaft 130.

[0058] Of course, in addition to the locking spring 220, in this embodiment, such as Figures 5 to 8As shown, the elastic deformable body can also be a C-shaped spring ring 230. The C-shaped spring ring 230 is sleeved and clamped on the outer wall surface of the elastic ring 210. The outer wall surface of the C-shaped spring ring 230 protrudes from the outer wall surface of the output shaft 100 and can elastically abut against the inner wall surface of the sleeve.

[0059] When the elastic deformable body is a C-shaped spring ring 230, in order to achieve axial limiting of the C-shaped spring ring 230 and prevent the C-shaped spring ring 230 from detaching from the free end of the step portion 110, one end of the elastic deformable body is stopped on the annular step surface 111, and the impact wrench also includes a stop structure 300, which is detachably connected to the end face 113 and has a limiting stop surface that stops the other end of the elastic deformable body.

[0060] Optionally, such as Figure 5 As shown, the shift structure 300 includes a limiting plate 310 and a connecting post 320 coaxially connected. The size of the limiting plate 310 is larger than the size of the end face 113. A mounting hole 114 is provided on the end face 113 along the first axis a. The end of the connecting post 320 away from the limiting plate 310 can be inserted into the mounting hole 114. An interference fit can be used to achieve a stable connection between the connecting post 320 and the mounting hole 114. Since the size of the limiting plate 310 is larger than the size of the end face 113, the bottom surface of the limiting plate 310 can prevent the elastic ring 210 and the C-shaped spring ring 230 from detaching from the free end of the square shaft 130 from the output shaft 100, thereby stably connecting the elastic ring 210 and the C-shaped spring ring 230 to the columnar surface 112 of the stepped portion 110 of the square shaft 130.

[0061] Of course, in addition to the structure described above, the gear shift structure 300 can also be as follows: Figure 6 and Figure 7As shown, the stop structure 300 may further include a retaining ring 340 and a fixing member 350. The size of the retaining ring 340 is larger than the size of the end face 113. The retaining ring 340 is provided with a countersunk hole. The cap of the fixing member 350 is placed in the countersunk hole. A threaded hole 116 is provided on the end face 113 along the first axis a. The screw of the fixing member 350 passes through the countersunk hole and is threaded into the threaded hole 116. This stop structure 300 can achieve a stable connection between the fixing member 350 and the square shaft 130 by using a threaded connection, thereby stably connecting the retaining ring 340 to the square shaft 130. Since the size of the retaining ring 340 is larger than the size of the end face 113, the bottom surface of the retaining ring 340 can restrict the elastic ring 210 and the C-type spring ring 230 from detaching from the free end of the square shaft 130 from the output shaft 100, thereby stably connecting the elastic ring 210 and the C-type spring ring 230 to the columnar surface 112 of the stepped portion 110 of the square shaft 130. Furthermore, the countersunk hole on the retaining ring 340 can conceal the nut of the fastener 350, improving aesthetics and preventing the exposed nut from scratching the sleeve. A limiting structure can also be provided between the retaining ring 340 and the end face 113; this limiting structure is the same as the one described above and will not be elaborated upon here.

[0062] Of course, in addition to the structure described above, the gear shift structure 300 can also be as follows: Figure 8 As shown, the stop structure 300 includes a limiting plate 310 and a stud 330 coaxially connected. The size of the limiting plate 310 is larger than the size of the end face 113. A threaded hole 116 is provided on the end face 113 along the first axis a, and the stud 330 is threaded into the threaded hole 116. This stop structure 300 achieves a stable connection between the stud 330 and the square shaft 130 through the threaded connection, thereby stably connecting the limiting plate 310 to the square shaft 130. Furthermore, since the size of the limiting plate 310 is larger than the size of the end face 113, the lower bottom surface of the limiting plate 310 can prevent the elastic ring 210 and the C-shaped spring ring 230 from detaching from the free end of the square shaft 130 from the output shaft 100, thereby stably connecting the elastic ring 210 and the C-shaped spring ring 230 to the cylindrical surface 112 of the stepped portion 110 of the square shaft 130.

[0063] Example 2:

[0064] This embodiment provides an impact wrench that can be used for disassembly, installation, and drilling. The impact wrench includes a housing, a motor, a battery, a transmission mechanism, and an output shaft 100. Specifically, the motor, battery, and transmission mechanism are all located inside the housing. The battery powers the motor. The motor shaft is connected to the input end of the transmission mechanism, and the output end of the transmission mechanism is connected to the output shaft 100. At least a portion of the output shaft 100 is located outside the housing and extends along a first axis a. Driven by the motor and transmission mechanism, the output shaft 100 can rotate around the first axis a. More specifically, the output shaft 100 includes a cylindrical shaft 120 and a square shaft 130 connected to each other. The square shaft 130 is located at the free end of the output shaft 100 away from the transmission mechanism. As the name suggests, the square shaft 130 is a columnar structure with four planes on its outer wall surface. Two adjacent planes are perpendicular to each other, and any two planes are parallel to each other, thus forming a square shape. The impact wrench also includes a socket that is detachably connected to the square shaft 130. By changing different sockets, the impact wrench can perform different functions.

[0065] In this embodiment, to achieve a stable connection between the square shaft 130 and the sleeve, and to ensure that the square shaft 130 has sufficient locking force on the sleeve, the connection between the sleeve and the square shaft 130 remains reliable even after multiple installations, disassemblies, and reassemblies, and disassemblies and reassemblies remain relatively easy. Figures 9 to 14 As shown, a stepped portion 110 is provided on the free end of the square shaft 130. The stepped portion 110 includes an annular stepped surface 111, a cylindrical surface 112, and an end face 113 connected in sequence. The annular stepped surface 111 is a horizontal plane, and the cylindrical surface 112 is perpendicular to the annular stepped surface 111, forming an annular groove with a vertical cross-section of L between them. The end face 113 is parallel to the annular stepped surface 111, and this end face 113 is also the end plane of the end of the output shaft 100 away from the transmission mechanism. The impact wrench also includes a locking structure 200, which includes an elastic deformable body. The elastic deformable body is coaxially locked and sleeved on the cylindrical surface 112. The rotation diameter of at least part of the elastic deformable body is greater than the maximum diagonal of any cross-section of the output shaft 100 perpendicular to the first axis a, so that when the sleeve is configured to be sleeved on the square shaft 130, the elastic deformable body can elastically press against the inner wall surface of the sleeve.

[0066] Because the elastic deformable body is made of elastic material, it can deform under external force. Therefore, when installing the sleeve onto the square shaft 130, the elastic deformable body can be appropriately compressed by rotating the sleeve under the mutual compression of the inner wall of the sleeve and the outer wall of the square shaft 130, making it easier to install the sleeve onto the square shaft 130. After assembly, the elastic deformable body tends to return to its original shape. This tendency causes the elastic deformable body to elastically press against the inner wall of the sleeve, thus ensuring that the sleeve is stably assembled onto the square shaft 130. When it is necessary to disassemble the sleeve, the elastic deformable body can be subjected to force by rotating the sleeve to appropriately reduce its size, allowing the sleeve to easily detach from the square shaft 130. Furthermore, by making at least a portion of the rotation diameter of the elastic deformable body greater than the maximum diagonal of any cross section of the output shaft 100 perpendicular to the first axis a, the impact wrench allows a portion of the elastic deformable body to contact the sleeve. Consequently, when the elastic deformable body undergoes the same deformation, the contact force is smaller, and the locking structure 200 is less prone to failure during long-term use, exhibiting high reliability and good durability.

[0067] To ensure the coaxiality of the elastic deformable body with the square shaft 130, such as Figures 9 to 14 As shown, the impact wrench also includes an elastic ring 210. The elastic ring 210 is a circular ring structure made of elastic material, capable of appropriate deformation under external force. The inner diameter of the elastic ring 210 is slightly smaller than the diameter of the cylindrical surface 112, and the outer diameter of the elastic ring 210 is smaller than the length of the longest diagonal on the square shaft 130. The elastic ring 210 is fitted onto the cylindrical surface 112, and the elastic deformable body is fitted onto the outer wall surface of the elastic ring 210.

[0068] Since the inner diameter of the elastic ring 210 is slightly smaller than the diameter of the cylindrical surface 112, it can be ensured that the elastic ring 210 can be fitted onto the cylindrical surface 112 under the action of external force, and can be tightened onto the cylindrical surface 112. This ensures that the elastic ring 210 can be stably fitted onto the stepped portion 110, thereby ensuring that the elastic ring 210 and the square shaft 130 have good coaxiality, and further ensuring that the elastic deformable body fitted onto the elastic ring 210 and the square shaft 130 have good coaxiality.

[0069] Optionally, in this embodiment, as Figures 9 to 11 As shown, the elastic deformable body includes a locking spring 220, which includes an inner ring and a spiral outer ring connected to the inner ring. The inner ring is sleeved and clamped onto the outer wall surface of the elastic ring 210. The outermost ring of the spiral outer ring protrudes from the outer wall surface of the output shaft 100 and can abut against the inner wall surface of the sleeve. Further optionally, the outer ring and the inner ring are not located at the same level, with the inner ring located near the end face 113 and the outer ring located near the annular step surface 111.

[0070] During the installation or removal of the sleeve, the locking spring 220 experiences radial compression at its helical section in the middle section, expanding outwards from both the start and end points. This reduces the maximum diameter of the spring, allowing the sleeve to be easily assembled and disassembled. By setting the elastic deformable body as a two-turn wound irregular spring, the diameter of each turn is smaller, resulting in a lower elastic coefficient. During the same deformation process, the contact force between the irregular spring and the sleeve is smaller, and the pressure on the structural surface is less, making it less prone to failure. Furthermore, according to the spring torque calculation formula and fatigue life calculation, the irregular spring with a reduced elastic coefficient K value is more durable and reliable.

[0071] When the elastic deformable body is a locking spring 220, in order to achieve axial limiting of the locking spring 220 and prevent the locking spring 220 from detaching from the free end of the step portion 110, one end of the elastic deformable body is abutted on the annular step surface 111, and the impact wrench also includes a stop structure 300, which is detachably connected to the end face 113 and has a limiting stop surface that stops the other end of the elastic deformable body.

[0072] Optionally, such as Figure 9 and Figure 10 As shown, the stop structure 300 includes a fixing ring 340 and a first retaining ring 360. A mounting post 117 is protruding along the first axis a on the end face 113. An annular groove 118 is provided on the end of the mounting post 117 away from the end face 113. The fixing ring 340 is sleeved on the mounting post 117, and the outer diameter of the fixing ring 340 is larger than the size of the end face 113. The annular groove 118 and the end face 113 are located on both sides of the fixing ring 340. The first retaining ring 360 is engaged in the annular groove 118, and the outer diameter of the first retaining ring 360 is larger than the inner diameter of the fixing ring 340. The shift structure 300 uses the first retaining ring 360 to engage in the annular groove 118, thereby restricting the position of the locking spring 220 and the elastic ring 210 and preventing the elastic ring 210 and the locking spring 220 from detaching from the free end of the square shaft 130 from the output shaft 100. This ensures that the elastic ring 210 and the locking spring 220 are stably connected to the cylindrical surface 112 of the stepped portion 110 of the square shaft 130.

[0073] Optionally, to prevent the fixed ring 340 from rotating, a limiting structure is provided between the fixed ring 340 and the end face 113. Specifically, the limiting structure consists of a limiting block 341 and a limiting groove 115. One of the limiting block 341 and the limiting groove 115 is disposed on the annular surface of the fixed ring 340 near the end face 113, and the other is disposed on the end face 113. The limiting block 341 and the limiting groove 115 are engaged, thereby limiting the fixed ring 340 and preventing the fixed ring 340 from rotating around the first axis a.

[0074] Of course, in addition to the structure described above, the gear shift structure 300 can also be as follows: Figure 11As shown, the stop structure 300 includes a second retaining ring 370. An annular limiting groove 119 is provided on the cylindrical surface 112. The annular limiting groove 119 and the annular stepped surface 111 are located on both sides of the elastic deformable body. The second retaining ring 370 is engaged with the annular limiting groove 119 and abuts against the elastic deformable body. The stop structure 300 has a simple structure. By providing an annular limiting groove 119 on the cylindrical surface 112 and engaging the second retaining ring 370 in the annular limiting groove 119, the second retaining ring 370 restricts the position of the locking spring 220 and the elastic ring 210, preventing the elastic ring 210 and the locking spring 220 from detaching from the free end of the square shaft 130 from the output shaft 100. This ensures that the elastic ring 210 and the locking spring 220 are stably connected to the cylindrical surface 112 of the stepped portion 110 of the square shaft 130.

[0075] Of course, in addition to the locking spring 220, in this embodiment, such as Figures 12 to 14 As shown, the elastic deformable body can also be a C-shaped spring ring 230. The C-shaped spring ring 230 is sleeved and clamped on the outer wall surface of the elastic ring 210. The outer wall surface of the C-shaped spring ring 230 protrudes from the outer wall surface of the output shaft 100 and can elastically abut against the inner wall surface of the sleeve.

[0076] When the elastic deformable body is a C-shaped spring ring 230, in order to achieve axial limiting of the C-shaped spring ring 230 and prevent the C-shaped spring ring 230 from detaching from the free end of the step portion 110, one end of the elastic deformable body is stopped on the annular step surface 111, and the impact wrench also includes a stop structure 300, which is detachably connected to the end face 113 and has a limiting stop surface that stops the other end of the elastic deformable body.

[0077] Optionally, such as Figure 12 and Figure 13As shown, the stop structure 300 includes a fixing ring 340 and a first retaining ring 360. A mounting post 117 is protruding along the first axis a on the end face 113. An annular groove 118 is provided on the end of the mounting post 117 away from the end face 113. The fixing ring 340 is sleeved on the mounting post 117, and the outer diameter of the fixing ring 340 is larger than the size of the end face 113. The annular groove 118 and the end face 113 are located on both sides of the fixing ring 340. The first retaining ring 360 is engaged in the annular groove 118, and the outer diameter of the first retaining ring 360 is larger than the inner diameter of the fixing ring 340. The stop structure 300 uses a first retaining ring 360 to engage within the annular groove 118, thereby restricting the position of the locking spring 220 and the elastic ring 210. This prevents the elastic ring 210 and the locking spring 220 from detaching from the free end of the square shaft 130 from the output shaft 100, thus ensuring a stable connection between the elastic ring 210 and the locking spring 220 on the cylindrical surface 112 of the stepped portion 110 of the square shaft 130. A similar limiting structure can also be provided between the fixing ring 340 and the end face 113. This limiting structure is the same as the one described above and will not be elaborated upon here.

[0078] Of course, in addition to the structure described above, the gear shift structure 300 can also be as follows: Figure 14 As shown, the stop structure 300 includes a second retaining ring 370. An annular limiting groove 119 is provided on the cylindrical surface 112. The annular limiting groove 119 and the annular stepped surface 111 are located on both sides of the elastic deformable body. The second retaining ring 370 is engaged with the annular limiting groove 119 and abuts against the elastic deformable body. The stop structure 300 has a simple structure. By providing an annular limiting groove 119 on the cylindrical surface 112 and engaging the second retaining ring 370 in the annular limiting groove 119, the second retaining ring 370 restricts the position of the locking spring 220 and the elastic ring 210, preventing the elastic ring 210 and the locking spring 220 from detaching from the free end of the square shaft 130 from the output shaft 100. This ensures that the elastic ring 210 and the locking spring 220 are stably connected to the cylindrical surface 112 of the stepped portion 110 of the square shaft 130.

[0079] Compared to the gear structure 300 in Embodiment 1, the gear structure 300 provided in this embodiment does not require drilling holes in the square shaft 130, thus avoiding damage to the cross section of the output shaft 100 that transmits torque, maximizing the protection of the structural strength of the output shaft 100, and solving the problem of early low strength of the output shaft 100 leading to fracture failure.

[0080] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An impact wrench, comprising: An output shaft extends along a first axis a and is configured to rotate about the first axis a, the output shaft comprising a square shaft; A sleeve, wherein the sleeve is detachably fitted onto the square shaft, characterized in that... The free end of the square shaft is provided with a stepped portion, which includes an annular stepped surface, a columnar surface and an end face connected in sequence. The impact wrench also includes a locking structure, which includes an elastic deformable body. The elastic deformable body is coaxially locked and sleeved on the cylindrical surface. The at least part of the winding diameter of the elastic deformable body is greater than the maximum diagonal of any cross section on the output shaft perpendicular to the first axis a, so that when the sleeve is configured to be sleeved on the square shaft, the elastic deformable body can elastically press against the inner wall surface of the sleeve. The locking structure also includes an elastic ring, which is sleeved on the cylindrical surface, and the elastic deformable body is sleeved on the outer wall surface of the elastic ring.

2. The impact wrench according to claim 1, characterized in that, One end of the elastic deformable body abuts against the annular step surface; The impact wrench also includes a stop structure, which is detachably connected to the stepped portion and has a limiting stop surface that stops the other end of the elastic deformable body.

3. The impact wrench according to claim 2, characterized in that, A mounting hole is provided on the end face along the first axis a; The stop structure includes a limiting plate and a connecting post connected coaxially. The size of the limiting plate is larger than the size of the end face, and the end of the connecting post away from the limiting plate can be inserted into the mounting hole.

4. The impact wrench according to claim 2, characterized in that, A threaded hole is provided on the end face along the first axis a; The stop structure includes a fixing ring and a fixing member. The size of the fixing ring is larger than the size of the end face. The fixing ring is provided with a countersunk hole. The cap of the fixing member is placed in the countersunk hole. The screw of the fixing member passes through the countersunk hole and is threaded into the threaded hole.

5. The impact wrench according to claim 2, characterized in that, A threaded hole is provided on the end face along the first axis a; The stop structure includes a limiting plate and a stud connected coaxially. The size of the limiting plate is larger than the size of the end face, and the stud is threaded into the threaded hole.

6. The impact wrench according to claim 2, characterized in that, A mounting post is protruding along the first axis a on the end face, and an annular groove is provided on the end of the mounting post away from the end face; The stop structure includes a fixed ring and a first retaining ring. The fixed ring is sleeved on the mounting post, and the outer diameter of the fixed ring is larger than the size of the end face. The annular groove and the end face are located on both sides of the fixed ring. The first retaining ring is engaged in the annular groove, and the outer diameter of the first retaining ring is larger than the inner diameter of the fixed ring.

7. The impact wrench according to claim 2, characterized in that, An annular limiting groove is provided on the columnar surface, and the annular limiting groove and the annular stepped surface are located on both sides of the elastic deformable body; The stop structure includes a second retaining ring, which engages with the annular limiting groove and abuts against the elastic deformable body.

8. The impact wrench according to claim 1, characterized in that, The elastic deformable body includes a locking spring, which includes an inner ring and a spiral outer ring connected to the inner ring. The inner ring is sleeved and clamped to the outer wall surface of the elastic ring, and the outermost ring of the spiral outer ring protrudes from the outer wall surface of the output shaft and can abut against the inner wall surface of the sleeve.

9. The impact wrench according to claim 1, characterized in that, The elastic deformable body includes a C-shaped spring ring, which is sleeved and clamped to the outer wall surface of the elastic ring. The outer wall surface of the C-shaped spring ring protrudes from the outer wall surface of the output shaft and can elastically abut against the inner wall surface of the sleeve.

10. The impact wrench according to claim 4 or 6, characterized in that, A limiting structure is provided between the fixing ring and the end face.

11. An impact wrench, comprising: An output shaft extends along a first axis a and is configured to rotate about the first axis a, the output shaft comprising a square shaft; A sleeve, wherein the sleeve is detachably fitted onto the square shaft, characterized in that... The free end of the square shaft is provided with a stepped portion, which includes an annular stepped surface, a columnar surface and an end face connected in sequence. The impact wrench also includes a locking structure, which includes an elastic deformable body that is coaxially locked and sleeved on the cylindrical surface. The impact wrench also includes a stop structure, which is detachably connected to the stepped portion and has a limiting stop surface that stops the other end of the elastic deformable body. The locking structure also includes an elastic ring, which is sleeved on the cylindrical surface, and the elastic deformable body is sleeved on the outer wall surface of the elastic ring.

Images