Force limiting wrench

Abstract

The utility model belongs to the technical field of dental medical instruments, and relates to a force limiting wrench. The force limiting wrench comprises a shell, a torque limiting assembly and a gland, the torque limiting assembly comprises a rotating shaft and a ratchet wheel arranged on the rotating shaft, the rotating shaft is rotationally connected with the shell, a plurality of tooth grooves meshed with the ratchet wheel are distributed in the inner wall of the shell, the inner wall of the shell is further provided with protruding edges, and the protruding edges and the tooth grooves are arranged at intervals. The gland is arranged on the rotating shaft and located between the protruding edge and the ratchet wheel, and a wrench position groove is formed in the axis of the rotating shaft. The screwing torque can be reasonably controlled, the situation that a user is scratched by a working tip during use is reduced, and assembling and disassembling are easy.

Description

Technical Field

[0001] This application relates to the technical field of dental medical devices, and more specifically, to a force-limiting wrench. Background Art

[0002] Dental medical devices mainly consist of a main unit, a handle, various types of working tips, and a foot switch; the working tip is the main tool for cutting, and its tail end is connected to the head of the handle through a thread. It is mostly an irregular, pointed and thin part, and the working tip needs to be frequently disassembled and replaced.

[0003] Currently, most of the existing force-limiting wrenches use a retaining ring and a wrench cover to position the ratchet. Its structure is complex, and the wrench cover, ratchet, and retaining ring need to be installed in cooperation in a certain order. Moreover, in a wrench seat with a smaller diameter, a circlip pliers is required to install the circlip on the wrench cover, resulting in difficult installation and disassembly. Utility Model Content

[0004] To solve the above technical problems, the embodiments of this application provide a force-limiting handle, adopting the following technical solutions:

[0005] A force-limiting wrench includes: a housing, a torque-limiting component, and a gland. The torque-limiting component includes a rotating shaft and a ratchet provided on the rotating shaft. The rotating shaft is rotatably connected to the housing. Multiple tooth grooves meshing with the ratchet are distributed on the inner wall of the housing. A convex edge spaced from the tooth grooves is further provided on the inner wall of the housing. The gland is provided on the rotating shaft and is located between the convex edge and the ratchet. A wrench position groove is provided at the axis of the rotating shaft.

[0006] Further, the rotating shaft includes a shaft body and an installation groove provided around the outer wall of the shaft body. The wrench position groove is provided at the axis of the end of the shaft body close to the gland. The ratchet includes a ratchet ring and multiple pawls provided around the outer wall of the ratchet ring. The ratchet ring is provided in the installation groove, and the pawls mesh with the tooth grooves.

[0007] Further, a flat position hole is provided in the wrench position groove, and a limit groove is provided at the end of the shaft body away from the gland. The wrench position groove, the flat position hole, and the limit groove are communicated.

[0008] Further, the diameter of the wrench position groove gradually increases in the direction away from the ratchet.

[0009] Further, the housing includes a cylinder body and an installation ring provided at the end of the cylinder body. The tooth grooves are provided at one end of the cylinder body close to the installation ring. The convex edge is provided in the middle of the cylinder body. The rotating shaft is rotatably provided on the installation ring, and the ratchet abuts against the end face of the installation ring.

[0010] Further, a groove is provided on the outer wall of the cylinder body.

[0011] Further, the convex edge is provided with a guiding surface, and the cross-sectional area of the convex edge gradually increases in the direction towards the ratchet wheel; and / or

[0012] There is a gap between the surface of one end of the convex edge close to the ratchet wheel and the surface of one end of the gland away from the ratchet wheel, and the value of the gap is 0.1 mm to 0.2 mm.

[0013] Further, the gland has a lower surface close to the ratchet wheel and an upper surface away from the ratchet wheel; along the plane direction from the axis of the rotating shaft to the inner wall of the outer shell, the distances between the upper surface and the ratchet wheel gradually increase.

[0014] Further, a through hole penetrating through the upper and lower ends is provided in the middle of the gland, and the gland is sleeved on the rotating shaft through the through hole; and / or

[0015] The lower surface is an arc surface, and the tangent of any point on the lower surface has an included angle with the vertical direction, and the included angle is 100° to 200°.

[0016] Further, at least one air vent hole penetrating through the upper and lower ends is provided on the gland.

[0017] Compared with the prior art, the embodiments of the present application mainly have the following beneficial effects: The convex edge can prevent the gland from being disengaged from the outer shell from bottom to top, and the gland can limit the position of the torque limiting component, thereby realizing the fixation of the torque limiting component. The present application can not only reasonably control the screwing torque, but also reduce the situation that the user is scratched by the working tip. In addition, in the present application, the rotating shaft of the torque limiting component is placed inside the outer shell, and after the ratchet wheel is engaged with the tooth groove, the gland is pressed into the outer shell from top to bottom from the convex edge, and the overall force limiting wrench can be assembled; compared with the prior art, the present application does not need to be provided with a retaining ring, nor does it need to use auxiliary tools such as a circlip pliers for installation, reducing the installation steps and the installation difficulty; when disassembly is required, press down one end of the gland away from the convex edge, and the gland and the torque limiting component can be removed, without using a circlip pliers to first remove the retaining ring and then disassemble the torque limiting component, reducing the disassembly steps and the disassembly difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the solutions of the present application, the following will briefly introduce the drawings required to be used in the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0019] Figure 1It is a top view of a torque-limiting wrench provided by an embodiment of the present application;

[0020] Figure 2 is Figure 1 a cross-sectional view taken along line A-A in

[0021] Figure 3 is Figure 2 a schematic diagram of a gland in

[0022] Figure 4 It is an exploded view of a torque-limiting wrench provided by an embodiment of the present application;

[0023] Figure 5 is Figure 1 a schematic diagram after omitting the gland;

[0024] Figure 6 It is a schematic diagram of a torque-limiting assembly in a torque-limiting wrench provided by an embodiment of the present application;

[0025] Figure 7 is Figure 6 a schematic diagram of a rotating shaft in

[0026] Reference numerals: 1, housing; 11, tooth groove; 12, convex edge; 13, cylinder body; 14, mounting ring; 2, torque-limiting assembly; 21, rotating shaft; 211, wrench position groove; 212, shaft body; 213, mounting groove; 214, ring body; 215, flat position hole; 216, limiting groove; 22, ratchet; 221, ratchet ring; 222, ratchet pawl; 3, gland; 31, through hole; 32, ventilation hole. Detailed embodiments

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this application or the above drawings are used to distinguish different objects and not to describe a specific order.

[0028] Referring to "embodiment" herein means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0029] To enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings, where the X direction in the drawings is the planar direction and the Y direction is the vertical direction.

[0030] An embodiment of this application provides a torque-limiting wrench. As Figures 1 to 4 shown, it includes: a housing 1, a torque-limiting assembly 2, and a gland 3. The torque-limiting assembly 2 includes a rotating shaft 21 and a ratchet 22 provided on the rotating shaft 21. The rotating shaft 21 is rotatably connected to the housing 1. A plurality of tooth grooves 11 meshing with the ratchet 22 are distributed on the inner wall of the housing 1. A convex edge 12 spaced from the tooth grooves 11 is further provided on the inner wall of the housing 1. The gland 3 is provided on the rotating shaft 21, and the gland 3 is located between the convex edge 12 and the ratchet 22. A wrench bit groove 211 is provided at the axis of the rotating shaft 21.

[0031] An assembly method of the torque-limiting wrench provided by an embodiment of this application is: place the rotating shaft 21 of the torque-limiting assembly 2 into the housing 1, and after the ratchet 22 is meshed with the tooth grooves 11, press the gland 3 into the housing 1 from the convex edge 12 from top to bottom, and the overall torque-limiting wrench can be assembled.

[0032] The working principle of the torque-limiting wrench provided by an embodiment of this application is: First, put the wrench bit groove 211 on the screwing flat position of the working tip; then, rotate the housing 1, the housing 1 transmits the torque to the ratchet 22, the ratchet 22 makes a relative movement with the tooth grooves 11, and the pawl 222 is elastically deformed under the resistance. As the torque continues to increase, the pawl 222 overcomes the sliding friction force between it and the tooth grooves 11, and the ratchet teeth of the torque-limiting assembly 2 and the rotating shaft 21 rotate synchronously to complete the installation and disassembly of the working tip.

[0033] The beneficial effect of the torque-limiting wrench provided by an embodiment of this application is: the convex edge 12 can prevent the gland 3 from being disengaged from the housing 1 from bottom to top, and the gland 3 can limit the position of the torque-limiting assembly, thereby realizing the fixation of the torque-limiting assembly. This application can not only reasonably control the screwing torque, but also reduce the situation that users are scratched by the working tip.

[0034] In addition, in this application, after the rotating shaft 21 of the torque-limiting assembly 2 is placed in the housing 1 and the ratchet 22 is meshed with the tooth grooves 11, the gland 3 is pressed into the housing 1 from the convex edge 12 from top to bottom, and the overall torque-limiting wrench can be assembled; compared with the prior art, this application does not need to set a retaining ring, nor does it need to use auxiliary tools such as a circlip pliers for installation, reducing the installation steps and the installation difficulty; when disassembly is required, press down one end of the gland 3 away from the convex edge 12, and the gland 3 and the torque-limiting assembly 2 can be removed. There is no need to use a circlip pliers to first remove the retaining ring and then disassemble the torque-limiting assembly 2, reducing the disassembly steps and the disassembly difficulty.

[0035] In this embodiment, a plurality of tooth grooves 11 are evenly distributed on the circumferential bottom of the housing 1.

[0036] Further, the housing 1 and the gland 3 are plastic parts; the performance of the plastic meets the requirements of high temperature and high pressure, and thus can meet the use strength and high-temperature steaming disinfection.

[0037] As Figures 2 to 7 shown, further, the rotating shaft 21 includes a shaft body 212 and an installation groove 213 arranged around the outer wall of the shaft body 212. The wrench position groove 211 is arranged at the center of one end of the shaft body 212 close to the gland 3. The ratchet 22 includes a ratchet ring 221 and a plurality of pawls 222 arranged around the outer wall of the ratchet ring 221. The ratchet ring 221 is arranged in the installation groove 213, and the pawls 222 are engaged with the tooth grooves 11.

[0038] In this embodiment, when the pawl 222 is subjected to resistance, it will undergo elastic deformation. The pawl 222 undergoes centripetal deformation. When the torque continues to increase, the elastic deformation amount of the pawl 222 increases, and the pawl 222 and the tooth groove 11 undergo relative sliding, and a "click" sound will be heard. This is the collision sound of the pawl 222 entering another adjacent tooth groove 11 from the initial tooth groove 11, indicating that the set torque value has been reached during screwing. At this time, increasing the torque value further will not affect the screwing torque of the working tip, achieving the effect of effectively controlling the torque.

[0039] In this embodiment, when preparing the torque limiting assembly 2, the shaft body 212 is used as an insert, the shaft body 212 is fixedly placed in an injection mold, and the ratchet 22 is arranged at the installation groove 213 through an injection molding process, so that the shaft body 212 and the ratchet 22 are made into an integral part to prevent the ratchet 22 from separating from the shaft body 212.

[0040] Further, the shaft body 212 is a metal part.

[0041] Further, the extending direction of the pawl 222 is tangent to the circumferential direction of the ratchet ring 221.

[0042] Further, the number of tooth grooves 11 is greater than the number of pawls 222; to ensure the continuous sliding of the pawls 222 in the tooth grooves 11.

[0043] As Figure 7 shown, further, two ring bodies 214 are wound around the outer periphery of the shaft body 212. The space between the two ring bodies 214 forms the installation groove 213. In the vertical direction, the end face of the ratchet 22 is parallel to or lower than the end face of the ring body 214 arranged adjacent to the gland 3.

[0044] In this embodiment, interference between the ratchet 22 and the gland 3 is avoided.

[0045] Optionally, the installation groove 213 is formed by inward depression of the outer periphery of the shaft body 212.

[0046] Such as Figure 2 , 6 , as shown in FIG. 7, further, a flat position hole 215 is provided in the wrench position groove 211, a limiting groove 216 is provided at one end of the shaft body 212 away from the gland 3, and the wrench position groove 211, the flat position hole 215 and the limiting groove 216 communicate with each other.

[0047] In this embodiment, the limiting groove 216 can allow the tip of the workpiece to penetrate and fix the lower part of the working tip, so that the flat position hole 215 is in screw fit with the flat position in the middle of the working tip, improving the loading and unloading efficiency of the working tip. The wrench position groove 211 can prevent the tip of the working tip from colliding with the shaft body 212, reducing the damage to the tip of the working tip.

[0048] Further, the groove diameter of the wrench position groove 211 gradually increases in a direction away from the ratchet wheel 22.

[0049] In this embodiment, the groove diameter of the wrench position groove 211 gradually increases in a direction away from the ratchet wheel 22, making the shape of the wrench position groove 211 similar to an inverted cone, so as to better accommodate the working tip, further preventing the tip of the working tip from colliding with the shaft body 212 and reducing the damage to the tip of the working tip.

[0050] Such as Figure 2 , 4 , as shown, further, the housing 1 includes a cylinder body 13 and an installation ring 14 provided at the end of the cylinder body 13. The tooth groove 11 is provided at one end of the cylinder body 13 close to the installation ring 14. The convex edge 12 is provided in the middle of the cylinder body 13. The rotating shaft 21 is rotatably provided on the installation ring 14, and the ratchet wheel 22 abuts against the end face of the installation ring 14.

[0051] In this embodiment, the ratchet wheel 22 abuts against the end face of the installation ring 14, and the gland 3 is located between the convex edge 12 and the ratchet wheel 22. Therefore, the installation ring 14 cooperates with the gland 3 to limit the axial movement range of the ratchet wheel 22 and prevent the ratchet wheel 22 from disengaging from the tooth groove 11.

[0052] Further, the cylinder body 13, the installation ring 14 and the convex edge 12 are integrally formed.

[0053] Further, the outer wall of the cylinder body 13 is an arc surface.

[0054] In this embodiment, the outer wall of the cylinder body 13 is an arc surface to adapt to the grasping habit of the user.

[0055] Further, a groove (not shown) is provided on the outer wall of the cylinder body 13.

[0056] In this embodiment, the groove on the outer wall of the cylinder body 13 can increase the grasping friction force and improve the user experience.

[0057] Furthermore, the convex edge 12 is provided with a guiding surface (not shown), and the cross-sectional area of the convex edge 12 gradually increases in the direction towards the ratchet wheel 22.

[0058] In this embodiment, the gland 3 can slide along the guiding surface so as to press the gland 3 into the housing 1 from the convex edge 12 from top to bottom; and since the cross-sectional area of the convex edge 12 gradually increases in the direction towards the ratchet wheel 22, it is avoided that the gland 3 disengages from the housing 1 from bottom to top, so that there is no need to use glue or screws for locking the gland 3 later, thus simplifying the assembly process of the torque-limiting wrench.

[0059] Furthermore, there is a gap between the surface of the end of the convex edge 12 adjacent to the ratchet wheel 22 and the surface of the end of the gland 3 away from the ratchet wheel 22, and the value of the gap is 0.1 mm to 0.2 mm.

[0060] In some alternative embodiments of this embodiment, the value of the gap is any one or the range between any two of 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, 0.2 mm, etc.

[0061] In this embodiment, the gap can prevent the ratchet wheel 22 from closely fitting with the gland 3, prevent the sliding friction force between the two from being too large, and thus avoid the problems of difficult rotation of the ratchet wheel 22 and too large torque value.

[0062] As Figure 3 shown, furthermore, the gland 3 has a lower surface close to the ratchet wheel 22 and an upper surface away from the ratchet wheel 22; along the plane direction from the axis of the rotating shaft 21 to the inner wall of the housing 1, the distances between the upper surface and the upper surface and the ratchet wheel 22 gradually increase.

[0063] In this embodiment, along the plane direction from the axis of the rotating shaft 21 to the inner wall of the housing 1, the distances between the upper surface and the upper surface and the ratchet wheel 22 gradually increase, so that the gland 3 forms a structure with a convex outermost end and a concave middle part, so that when the gland 3 is pressed into the housing 1 from the convex edge 12 from top to bottom, the gland 3 can undergo elastic deformation.

[0064] Furthermore, a through hole 31 penetrating through the upper and lower ends is provided in the middle of the gland 3, and the gland 3 is sleeved on the rotating shaft 21 through the through hole 31.

[0065] In this embodiment, the cooperation between the rotating shaft 21 and the through hole 31 realizes the positioning of the gland 3, facilitating the installation of the gland 3.

[0066] Further, the lower surface is an arc surface, and the tangent of any point on the lower surface forms an angle α with the vertical direction, and the angle α is 100 to 200°.

[0067] In some alternative embodiments of this embodiment, the angle α is any one of 100°, 110°, 120°, 130°, 140°, 150°, 160°, 170°, 180°, 190°, 200°, etc. or the range between any two of them.

[0068] In this embodiment, the curvature of the lower surface is restricted by the angle. By setting different angles, the lower surface can meet different curvatures, which is not limited in this application.

[0069] Further, at least one air vent 32 penetrating through the upper and lower ends is provided on the gland 3.

[0070] In this embodiment, an air vent is provided on the gland 3 to ensure the fluidity of high-temperature steam during cooking and improve the cooking and sterilization efficiency.

[0071] Further, the air vent 32 and the through hole 31 are arranged at intervals.

[0072] Obviously, the embodiments described above are only a part of the embodiments of this application, rather than all the embodiments. The preferred embodiments of this application are shown in the drawings, but do not limit the patent scope of this application. This application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of this application more thorough and comprehensive. Although this application has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing specific embodiments, or perform equivalent replacements for some of the technical features. Any equivalent structure made by using the specification and drawings of this application, directly or indirectly applied in other related technical fields, is equally within the scope of the patent protection of this application.

Claims

1. A torque-limiting wrench, characterized in that, Comprising: A housing, a torque limiting component and a gland. The torque limiting component includes a rotating shaft and a ratchet wheel provided on the rotating shaft. The rotating shaft is rotatably connected to the housing. A plurality of tooth grooves meshing with the ratchet wheel are distributed on the inner wall of the housing. A convex edge spaced from the tooth grooves is further provided on the inner wall of the housing. The gland is provided on the rotating shaft and is located between the convex edge and the ratchet wheel. A wrench position groove is provided at the axis of the rotating shaft.

2. The force-limiting wrench according to claim 1, characterized in that, The rotating shaft includes a shaft body and an installation groove provided around the outer wall of the shaft body. The wrench position groove is provided at the axis of the end of the shaft body close to the gland. The ratchet wheel includes a ratchet ring and a plurality of pawls provided around the outer wall of the ratchet ring. The ratchet ring is provided in the installation groove, and the pawls mesh with the tooth grooves.

3. The force-limiting wrench according to claim 2, wherein, A flat position hole is provided in the wrench position groove. A limiting groove is provided at the end of the shaft body away from the gland. The wrench position groove, the flat position hole and the limiting groove are communicated.

4. The force-limiting wrench according to any one of claims 1 to 3, characterized in that, The groove diameter of the wrench position groove gradually increases in the direction away from the ratchet wheel.

5. The force-limiting wrench according to any one of claims 1 to 3, characterized in that, The housing includes a cylinder body and an installation ring provided at the end of the cylinder body. The tooth grooves are provided at one end of the cylinder body close to the installation ring. The convex edge is provided in the middle of the cylinder body. The rotating shaft is rotatably provided on the installation ring, and the ratchet wheel abuts against the end face of the installation ring.

6. The force-limiting wrench according to claim 5, wherein, A groove is provided on the outer wall of the cylinder body.

7. The force limiting wrench according to any one of claims 1 to 3, wherein The convex edge is provided with a guiding surface, and the cross-sectional area of the convex edge gradually increases in the direction towards the ratchet wheel; and / or There is a gap between the surface of the end of the convex edge close to the ratchet wheel and the surface of the end of the gland away from the ratchet wheel, and the value of the gap is 0.1 mm to 0.2 mm.

8. The force-limiting wrench according to any one of claims 1 to 3, characterized in that, The gland has a lower surface close to the ratchet wheel and an upper surface away from the ratchet wheel; along the plane direction from the axis of the rotating shaft to the inner wall of the housing, the distances between the upper surface and the upper surface and the ratchet wheel gradually increase.

9. The force-limiting wrench according to claim 8, characterized in that, A through hole penetrating the upper and lower ends is provided in the middle of the gland, and the gland is sleeved on the rotating shaft through the through hole; and / or The lower surface is an arc surface, and the tangent of any point on the lower surface forms an angle with the vertical direction, and the angle is 100 to 200°.

10. The force-limiting wrench according to any one of claims 1 to 3, characterized in that, At least one through hole penetrating the upper and lower ends is provided on the gland.

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