Rolling element limiting device for bearing impact test

Abstract

This invention discloses a rolling element limiting device for bearing impact testing, belonging to the field of bearing testing technology. The device mainly includes a support base, a bearing mounting shaft, a pin, a fixed shaft, a limiting bracket seat, and a nylon rod. The support base supports the entire device; the bearing mounting shaft mounts the bearing to be tested; the pin fixes the relative position between the bearing mounting shaft and the support base; a limiting bracket seat and a fixed shaft are added, with a ring of limiting holes on the limiting bracket seat; the nylon rod passes through the space between the inner and outer rings of the bearing, with its two ends inserted into the corresponding limiting holes of the limiting bracket seats on both sides of the bearing, precisely limiting the rolling element to the ideal test stress position; finally, the fixed shaft connects and fixes the two limiting bracket seats to the holes below the support base, forming a stable constraint. Advantages: It solves the problem of inaccurate rolling element positioning in bearing impact testing, efficiently and accurately ensuring the steel ball is in the target position, significantly improving the accuracy and reliability of the impact test results.

Description

Technical Field

[0001] This invention relates to the field of bearing performance testing technology, specifically to an auxiliary device for bearing impact testing, and particularly to a limiting device that can precisely limit the position of bearing rolling elements. Background Technology

[0002] Bearing impact load testing is an important method for simulating the impact resistance of bearings when suddenly subjected to impact loads, and it is usually carried out in the form of a drop hammer test. There are two main methods for transferring the test load: the bridge test through the line connecting the centers of the two balls and the straight-up test through the center line of the balls. Regardless of the method, ensuring that the rolling element (steel ball) at the point of force application is precisely located at the preset ideal target position is the key to ensuring the validity and accuracy of the test results.

[0003] Currently, in direct impact testing, it is difficult to precisely confine the stressed steel ball to the bearing's centerline; positioning usually relies on the operator's experience. This method of positioning introduces significant errors, causing the impact force to not accurately act on the target steel ball, severely affecting the repeatability and comparability of test data, and making it impossible to accurately assess the bearing's true impact resistance. Therefore, there is an urgent need for a device that can accurately and reliably confine the position of the bearing's rolling elements to meet the requirements of high-standard bearing impact testing. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a rolling element limiting device for bearing impact testing that is simple in structure, easy to operate, and accurate in positioning, so as to solve the technical problem that the rolling element cannot be accurately positioned in the impact test.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A rolling element limiting device for bearing impact testing mainly includes a support base, a bearing mounting shaft, a pin, a fixed shaft, a limiting bracket seat, and a nylon rod.

[0006] The support base is the base of the entire device and is used to support other components.

[0007] The bearing mounting shaft is used to mount the bearing to be tested. Its shaft diameter is fitted with the mounting hole of the support base, the inner hole of the bearing, and the mounting hole at the upper end of the limit bracket to ensure coaxiality and stability.

[0008] The pin is used to insert into the hole at the upper end of the support base and the through holes at both ends of the bearing mounting shaft, thereby fixing the bearing mounting shaft to the support base and preventing relative movement during the test.

[0009] The limiting bracket is one of the core improved components of this invention. It has a ring of carefully arranged limiting holes on its upper part and a through hole on its lower part. The diameter of the distribution circle of the limiting holes is designed according to the center diameter of the steel balls of the bearing to be tested. Therefore, different models of bearings can be adapted by replacing the limiting bracket with different specifications.

[0010] The nylon rod is made of a plastic material, possessing good toughness and a certain degree of rigidity. Its function is to pass through the space between the inner and outer rings of the bearing after the bearing is assembled onto the device, and to use its rod body to precisely push and confine the specific steel ball that needs to be subjected to impact to the ideal target force position (such as the bearing centerline in a direct-mount test).

[0011] The fixed shaft is used to finally lock the entire limiting structure. It passes through the through holes at the lower ends of the limiting bracket seats on both sides and the through holes at the lower end of the support base (both are transition fits), fastening the limiting bracket seats and the support base together, thereby ensuring that the position of the nylon rod is fixed and ultimately achieving reliable limiting of the steel ball.

[0012] The beneficial effects of this invention are as follows: Precise positioning: By using a nylon rod and a support with limiting holes, a specific rolling element can be precisely and reliably positioned at a preset test stress point, completely solving the problem of ambiguous positioning in traditional methods.

[0013] High versatility: By replacing the limit bracket seat of different specifications (the diameter of the limit hole distribution circle is different), it can be adapted to bearings of various sizes and models, and has a wide range of applications.

[0014] Simple and reliable structure: The entire device has an ingenious structural design, few parts, clear assembly relationships, simple operation, good stability, and will not introduce additional interference factors.

[0015] Improved testing efficiency and accuracy: After using this device, the impact load can be accurately applied to the target position in each test, which greatly improves the repeatability, comparability and accuracy of the test results, and provides a reliable guarantee for the objective evaluation of the bearing's impact resistance performance. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall assembly of the rolling element limiting device of the present invention.

[0017] Figure 2 This is a structural diagram of the limit bracket, highlighting the ring of limit holes at the top.

[0018] Figure 3 A schematic diagram illustrating the working principle of a nylon rod inserted between the inner and outer rings of a bearing to limit the movement of the steel ball.

[0019] (In the diagram: 1. Support base; 2. Bearing mounting shaft; 3. Pin; 4. Fixing shaft; 5. Limiting bracket seat; 51. Limiting hole; 6. Nylon rod) Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] like Figures 1 to 3 As shown, the assembly and usage steps of the rolling element limiting device for bearing impact testing provided by the present invention are as follows: First, select the corresponding specification of the limit bracket seat (5) according to the model of the bearing to be tested (such as the 0009249533 (MG30B7-5) roller bearing in the embodiment). The distribution circle diameter of the upper limit hole (51) of the bracket must be precisely matched with the center diameter of the steel ball of the bearing.

[0022] Then, the device is assembled: a. Pass the bearing mounting shaft (2) through the mounting hole of one side support base (1), the inner hole of the bearing to be tested, and the mounting hole of the other side support base (1) in sequence.

[0023] b. Insert the pin (3) into the hole at the upper end of the support base (1) and the through holes on both ends of the bearing mounting shaft (2) to fix the bearing mounting shaft (2) to the support base (1).

[0024] c. Gently move the outer ring of the bearing by hand to distribute the rolling elements evenly. Select the target steel ball that needs to withstand the impact, insert a nylon rod (6) into the gap between the inner and outer rings from one side of the bearing, and gently push it until the nylon rod (6) precisely pushes the target steel ball to the ideal stress position (for example, for a direct-up test, the steel ball needs to be pushed to the center line of the bearing).

[0025] d. Insert both ends of the nylon rod (6) into the corresponding limiting holes (51) on the upper end of the limiting bracket seat (5) that has been placed on both sides of the bearing.

[0026] e. Finally, the fixed shaft (4) is passed through the through hole at the lower end of the limit bracket seat (5) on one side, the through hole at the lower end of the support base (1), and the through hole at the lower end of the limit bracket seat (5) on the other side in sequence to achieve final fixation.

[0027] At this point, the target steel ball has been precisely positioned in the ideal location by the nylon rod (6). Place the entire assembled device on the platform of an impact testing machine (such as the WZJ6120-intelligent drop hammer impact testing machine), and adjust the drop hammer height (test hammer weight, for example, 100 kg) according to the test procedure (such as the direct-up test method described in the background art) to conduct the impact test.

[0028] Examples and Test Results The device of this invention was used to conduct an impact test on a roller bearing (outer ring material GCr15, external dimensions φ30*φ75.3*23.5 / 24) with model number 0009249533 (MG30B7-5).

[0029] Test Method: The rolling element limiting device described above is used to ensure that the stressed steel ball is accurately positioned at the target location. The testing machine is a WZJ6120 intelligent falling hammer impact testing machine with a hammer weight of 100kg. First, the falling hammer is lowered to contact the outer circle of the bearing, and the initial height h0 is measured; then the falling hammer is raised to the predetermined height hn, and the impact height h = hn - h0 is calculated. The test is conducted at the initially selected height. If the bearing is not damaged, the height is increased by Δh = 5mm each time, and the test is repeated until the bearing cracks. This height is recorded as the first failure height. Then, by finely adjusting the height near the first failure height and conducting multiple repeated tests, the reliable impact height of the bearing (i.e., the maximum height at which the bearing does not fail in multiple tests or the critical height at which the failure pattern changes) is determined, and the impact energy is calculated.

[0030] Test Results: The consistency of test data was significantly improved after using this limiting device. The impact limit height (minimum height at which the first crack appears) of this bearing model was determined to be 380mm (see the test record table; bearing number C1# developed a crack on the outer ring end face after an impact of 380mm). Through multiple sets of repeated tests in its vicinity (377mm, 374mm, 371mm, 368mm), the reliable average height H = 372.5mm was determined, and based on this, the impact potential energy (impact work) that the bearing can withstand was calculated as E = m * g * H = 100 * 9.8 * 0.3725 = 365.05 J.

[0031] Experiments show that the device of the present invention effectively ensures that the impact force is accurately applied to the target steel ball, and obtains bearing impact resistance performance data (limit height, reliable work) with good repeatability and accuracy, solving the problem of large dispersion of test results caused by inaccurate positioning in the past.

[0032] After the test is completed, the disassembly sequence is the reverse of the installation sequence.

[0033] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A rolling element limiting device for bearing impact testing, comprising a support base (1), a bearing mounting shaft (2), and a pin (3), characterized in that: It also includes a fixed shaft (4), at least two limiting bracket seats (5) and at least one nylon rod (6); the upper end of the limiting bracket seat (5) is provided with a ring of limiting holes (51) and the middle of the upper end is provided with an installation hole, and the lower end is provided with a through hole that cooperates with the fixed shaft (4); the nylon rod (6) can pass between the inner and outer rings of the bearing to be tested, and its two ends can be inserted into the corresponding limiting holes (51) of the limiting bracket seats (5) placed on both sides of the bearing; the fixed shaft (4) can pass through the through hole at the lower end of the support base (1) and the through hole at the lower end of the limiting bracket seat (5) to fix the limiting bracket seat (5) to the support base (1).

2. The rolling element limiting device for bearing impact testing according to claim 1, characterized in that: The shaft diameter of the bearing mounting shaft (2) is transitionally fitted with the mounting hole of the support base (1), the inner hole of the bearing to be tested, and the mounting hole at the upper end of the limiting bracket seat (5).

3. The rolling element limiting device for bearing impact testing according to claim 1, characterized in that: The fixed shaft (4) and the through hole at the lower end of the support base (1) and the through hole at the lower end of the limiting bracket (5) are in transition fit.

4. A rolling element limiting device for bearing impact testing according to claim 1, characterized in that: The nylon rod (6) is made of a plastic material.

5. A rolling element limiting device for bearing impact testing according to claim 1, 2, 3 or 4, characterized in that: The limiting bracket seat (5) can be replaced according to the center diameter of the steel ball of the bearing to be tested. The diameter of the limiting hole (51) distribution circle on the limiting bracket seat (5) of different sizes changes accordingly.

6. An installation method for bearing impact testing using the rolling element limiting device as described in any one of claims 1-5, characterized in that, Includes the following steps: (a) Pass the bearing mounting shaft (2) through the mounting hole of the support base (1) on one side, the inner hole of the bearing to be tested, and the mounting hole of the support base (1) on the other side in sequence; (b) Insert the pin (3) into the hole at the upper end of the support base (1) and the through holes on both ends of the bearing mounting shaft (2) to fix the relative position of the bearing mounting shaft (2) and the support base (1); (c) Pass the nylon rod (6) through the space between the inner and outer rings of the bearing to be tested, so that the steel ball that needs to be limited is limited to the target position; (d) Insert both ends of the nylon rod (6) into the corresponding limiting holes (51) at the upper end of the limiting bracket seat (5) which are placed on both sides of the bearing; (e) The fixed shaft (4) is passed through the through hole at the lower end of the limiting bracket seat (5) on one side, the through hole at the lower end of the support base (1), and the through hole at the lower end of the limiting bracket seat (5) on the other side in sequence to form a fixed constraint and ensure that the nylon rod (6) limits the steel ball.

7. A bearing impact test method, characterized in that, After precisely positioning a specific rolling element in the bearing using the rolling element limiting device as described in any one of claims 1-5 or the installation method as described in claim 6, a drop hammer impact test is then performed.

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