A duplex gear part inspection auxiliary device
Patent Information
- Application Number
- CN202522502544.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-26
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-11-26
AI Technical Summary
1、测试要求刚性支撑，但双联链轮的结构本身是悬空的、非刚性的，需要测试的关键部位（齿面），恰恰位于这个悬空结构的上方；测试所用的力非常大（150 kgf），足以使悬空的薄壁部分发生可观的弹性变形，这个弯曲过程会“吃掉”一部分能量，导致测试出的硬度值会出现虚假；
[0013]本实用新型的有益效果是：本实用新型解决了零件几何结构与测试原理之间的根本性矛盾，它的作用就是将实际的非刚性零件在测试局部区域“改造”成一个符合测试标准要求的、理想的刚性体，从而确保从硬度计上读取的每一个数据，都是材料真实的硬度反映，而不是一个包含结构变形误差的无效数字，这在质量控制上是至关重要的，一个虚假的高硬度值可能会让一个不合格的零件被误判为合格，导致其在现场过早失效。
Smart Images
Figure CN224839750U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to an auxiliary device for inspecting double gear parts, belonging to the field of mechanical technology. Background Technology
[0002] Many parts in the machinery industry require heat treatment for strengthening. After heat treatment, it is necessary to inspect the strengthening effect of the parts. Common inspection methods include Brinell hardness, Rockwell hardness, and Vickers hardness. Among them, Rockwell hardness is the most commonly used inspection method for finished parts after heat treatment.
[0003] The Rockwell hardness test is an indentation hardness test. Its core principle is: first, an initial test force is applied, pressing the indenter into the material to establish a reference depth; then, a main test force is applied, pressing the indenter further in; the main test force is then removed, leaving the initial test force; the hardness value is calculated using a formula based on the difference between the remaining indentation depth and the reference depth. This calculation is based on a strict assumption—that throughout the entire test, apart from the plastic deformation of the material beneath the indenter, the sample and support system themselves are "absolutely rigid," without any elastic deformation. Any elastic deformation of the support system would be directly included in the depth measurement, leading to severely distorted results.
[0004] Double sprockets are used to transmit power and change speed, and typically operate under heavy loads, high torque, and impact loads. When the chain meshes with the sprocket teeth, the main force is concentrated on the tooth surface, and the root of the tooth bears alternating bending stress, similar to the force on a gear. Therefore, the hardness of the tooth surface and high-stress areas is crucial. To meet the above performance requirements, sprockets are generally surface hardened.
[0005] After heat treatment of the tooth surface, there are the following difficulties in testing the hardness value of such parts: 1. The test requires rigid support, but the structure of the double sprocket is itself suspended and non-rigid. The key part to be tested (tooth surface) is located above this suspended structure. The force used in the test is very large (150 kgf), which is enough to cause considerable elastic deformation of the suspended thin-walled part. This bending process will "eat up" some energy, resulting in false hardness values in the test. 2. When testing in a suspended state, the huge concentrated load may cause plastic deformation or even damage to the sprocket. More importantly, any unstable displacement or sudden deformation during the test will cause impact and damage to the precision components such as the spindle and indenter of the hardness tester. 3. It is very dangerous for parts to suddenly slide or bounce under pressure, as this may cause injury to the operator. Utility Model Content
[0006] To overcome the shortcomings of the prior art, this utility model provides an auxiliary device for inspecting double gear parts. This device can effectively eliminate the above-mentioned problems and ensure the accuracy, repeatability and safety of the test.
[0007] The technical solution adopted by this utility model to solve its technical problem is: an auxiliary device for inspecting double gear parts, including an upper top plate and a lower top plate, wherein the upper top plate is installed above the lower top plate.
[0008] A cylinder is provided above one end of the top plate, and a vertical threaded hole is provided at the bottom of the top plate at the position opposite to the cylinder.
[0009] A vertical stud is fixedly connected to one end of the lower top plate. The position of the stud corresponds vertically to the position of the threaded hole, and the end of the stud is threaded into the threaded hole.
[0010] Furthermore, at the end closest to the cylinder, the side of the top plate is arc-shaped.
[0011] Furthermore, at the end near the stud, this side of the lower top plate is arc-shaped.
[0012] Furthermore, the upper and lower top plates are made of 45CrNiMoVA or 35CrNi3Mo high-alloy steel.
[0013] The beneficial effects of this utility model are: This utility model solves the fundamental contradiction between the geometric structure of the part and the testing principle. Its function is to "transform" the actual non-rigid part into an ideal rigid body that meets the testing standard requirements in the local testing area, thereby ensuring that every data read from the hardness tester is a true reflection of the material's hardness, rather than an invalid number containing structural deformation errors. This is crucial for quality control. A false high hardness value may cause a substandard part to be misjudged as qualified, leading to its premature failure in the field.
[0014] This invention can tightly fill and support the area below the suspended part, forming a rigid foundation that effectively resists test pressure, prevents deformation of the parts' teeth, and ensures that the standard test force is applied completely and accurately to the test point. It provides a unified and stable support benchmark; consistent support conditions can be obtained as long as the same auxiliary device is used, thereby ensuring the repeatability and comparability of test results; by distributing and supporting the load, it protects the expensive sprocket parts from damage other than indentation, while also protecting the hardness tester itself and extending its service life; it firmly stabilizes the parts on the platform, preventing any accidental movement and ensuring the safety of the testing process. Attached Figure Description
[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0016] Figure 1 This is a schematic diagram of the structure of this utility model.
[0017] Figure 2 This is a front view of the top plate of this utility model.
[0018] Figure 3 yes Figure 2 Top view.
[0019] Figure 4 This is a front view of the lower top plate of this utility model.
[0020] Figure 5 yes Figure 4 Top view.
[0021] Figure 6 This is a schematic diagram of the present invention in use.
[0022] Figure 7 This is a schematic diagram of the part.
[0023] Figure 8 yes Figure 7 A-A direction diagram.
[0024] Numbering on the map: 1. Top plate, 101. Cylinder, 102. Threaded hole, 2. Bottom plate, 201. Stud, 3. Part, 4. Hardness tester indenter, 5. Hardness tester pad. Detailed Implementation
[0025] like Figure 1 As shown in Figure 8, an auxiliary device for inspecting double gear parts includes an upper top plate 1 and a lower top plate 2. The upper top plate 1 is installed above the lower top plate 2. A cylinder 101 is provided above one end of the upper top plate 1. At a position opposite to the cylinder 101, a vertically threaded hole 102 is provided in the bottom of the upper top plate 1. The side of the upper top plate 1 near the cylinder 101 is arc-shaped. A vertically oriented stud 201 is fixedly connected to the top of one end of the lower top plate 2. The position of the stud 201 corresponds vertically to the position of the threaded hole 102, and the end of the stud 201 is threaded into the threaded hole 102. The side of the lower top plate 2 near the stud 201 is arc-shaped.
[0026] The upper top plate 1 is made of high alloy steel (45CrNiMoVA or 35CrNi3Mo) and is hardened to a hardness of 55-58HRC to ensure its wear resistance and extend its service life. A cylinder 101 is provided at one end of the upper top plate 1. The cylinder 101 is mainly used to support the upper surface of the suspended part 3. The upper surface of the cylinder 101 is polished to a surface finish Ra>0.63μ to ensure its fit with the surface of the part. An M10 threaded hole 102 is provided in the lower surface of the upper top plate 1. The threaded hole 102 is used to fix and connect the lower top plate 2.
[0027] The lower top plate 2 is also made of high alloy steel (45CrNiMoVA or 35CrNi3Mo) and is hardened to a hardness of 55-58HRC. One end of the lower top plate 2 is provided with a stud 201 with a cylindrical thread structure for connecting to the upper top plate 1. The lower part of the lower top plate 2 is a flat plate structure, and its bottom surface contacts the lower plane of the suspended part of the part 3 to provide support. The lower plane of the flat plate structure of the lower top plate 2 is polished to a surface finish Ra > 0.63μ to ensure its fit with the surface of the part. The upper top plate 1 and the lower top plate 2 are connected by threaded holes 102 and stud 201.
[0028] How to use: 1) Before performing hardness testing on part 3, thread the testing auxiliary device and adjust the total height of the device to be close to the size of the part 3 that is suspended in the air. 2) Place the device in the middle of part 3, with the arc side of the upper top plate 1 and the arc side of the lower top plate 2 close to part 3. Rotate the upper top plate 1 and finely adjust the height to ensure that the suspended part 3 is completely filled and pressed. 3) Perform Rockwell hardness test. Part 3 has a hardness tester pad 5 at the bottom and a hardness tester indenter 4 on top. 4) After the inspection is completed, loosen the top plate 1 of the inspection auxiliary device and remove it from part 3.
Claims
1. An auxiliary device for inspecting double-gear parts, characterized in that: It includes an upper top plate (1) and a lower top plate (2), wherein the upper top plate (1) is installed above the lower top plate (2); A cylinder (101) is provided above one end of the top plate (1), and a vertical threaded hole (102) is provided in the bottom of the top plate (1) at a position opposite to the cylinder (101). A vertical stud (201) is fixedly connected to one end of the lower top plate (2). The position of the stud (201) corresponds vertically to the position of the threaded hole (102). The end of the stud (201) is threaded into the threaded hole (102).
2. The auxiliary device for inspecting double gear parts according to claim 1, characterized in that: At the end near the cylinder (101), this side of the top plate (1) is arc-shaped.
3. The auxiliary device for inspecting double gear parts according to claim 1, characterized in that: At the end near the stud (201), this side of the lower top plate (2) is arc-shaped.
4. The auxiliary device for inspecting double gear parts according to claim 1, characterized in that: The upper top plate (1) and the lower top plate (2) are made of 45CrNiMoVA or 35CrNi3Mo high alloy steel.