A life test equipment for reciprocating linear motion parts

Abstract

The present invention provides a life test equipment for reciprocating linear motion parts, including a test workbench, an installation box, and a linear pulse test device, wherein the installation box includes a box body, a fork shaft and a gear shaft are installed in the box body, both ends of the gear shaft are provided with limit components, and a fork is provided on the fork shaft; the linear pulse test device includes: a linear pulse generator, connected to the gear shaft through an input shaft; a force sensor, measuring the theoretical shift force; a first displacement sensor, measuring the theoretical reciprocating displacement; in addition, a second displacement sensor for measuring the actual reciprocating displacement is provided at the position where the fork is located; and a pressure sensor for measuring the actual shift force is provided on the limit component. The present invention sets a sensor at a specific position of the test equipment to quickly verify the consistency between the design value and the actual value, thereby analyzing the unqualified principle, which is conducive to the optimization of the designer.

Description

Technical Field

[0001] The invention relates to the technical field of gearbox production, and in particular to a life test device for reciprocating linear motion parts. Background Art

[0002] With the rapid development of science and technology and the improvement of people's living standards, cars have become popular in people's lives. Among them, the mechanical gearbox is one of the key parts of the car, and its load-bearing capacity, safety performance and service life must be strictly verified. To ensure the safety and reliability of the gearbox, it is necessary to ensure that its internal parts are fully verified.

[0003] In mechanical transmissions, there is a type of parts: most of the parts (generally referred to as parts or components) of the devices such as the shift mechanism, clutch, and reverse light switch, whose motion law is reciprocating linear motion, and the life and performance reliability of these parts are related to the safety of the vehicle and the driving comfort. Therefore, it is very necessary to test and analyze the life of these reciprocating linear motion parts.

[0004] Take the synchronizer fork as an example. The traditional test method for this type of reciprocating linear motion parts is: first fix the synchronizer gear sleeve, use the reciprocating pulse test bench to move at S=L1 and S=L2 with a reciprocating tensile force of F=500N and a frequency of f=10Hz, until 200,000 times are completed or the tensile force F<490N alarm is set to stop, and check the wear of the fork head. However, the problem is that this method can only obtain test results, and it is impossible to analyze the specific factors or unreasonable parameter design of the reciprocating linear motion parts that lead to the final test failure, which is not conducive to the optimization of designers. Summary of the invention

[0005] Based on this, the purpose of the present invention is to provide a life test equipment for reciprocating linear motion components to solve the problem that the prior art cannot analyze the specific factors of reciprocating linear motion components or the unreasonable parameter design leads to the final test failure, which is not conducive to optimization by designers.

[0006] According to an embodiment of the present invention, a reciprocating linear motion component life test device includes a test bench, a mounting box arranged on the test bench, and a linear pulse test device connected to the other side of the mounting box, wherein the mounting box includes a box body, a shift fork shaft and a gear shaft for mounting a reciprocating linear motion component are installed in the box body, both ends of the gear shaft are provided with a limit component for limiting the installation position of the reciprocating linear motion component, and the shift fork shaft is provided with a shift fork for shifting the reciprocating linear motion component to reciprocate linear motion;

[0007] The linear pulse test device comprises:

[0008] A linear pulse generator connected to the gear shaft via an input shaft to drive the fork shaft to reciprocate linearly;

[0009] A force sensor for measuring a theoretical shifting force applied by the linear pulse generator to the shift fork shaft;

[0010] a first displacement sensor, measuring the theoretical reciprocating displacement applied to the fork shaft by the linear pulse generator;

[0011] In addition, a second displacement sensor for measuring the actual reciprocating displacement of the shift fork is provided at the position where the shift fork is located;

[0012] The limiting component is provided with a pressure sensor for measuring the actual shifting force of the reciprocating linear motion component.

[0013] Preferably, the input shaft is connected to the shift fork shaft via a connecting member.

[0014] Preferably, the connecting member comprises a connecting sleeve and a flange plate connected to each other, one of the connecting sleeve and the flange plate is arranged at the end of the input shaft, and the other is arranged at the end of the shift fork shaft.

[0015] Preferably, the reciprocating linear motion component life test equipment further includes an industrial computer, and the industrial computer is electrically connected to the force sensor, the first displacement sensor, the pressure sensor and the second displacement sensor respectively.

[0016] Preferably, the reciprocating linear motion component life test equipment further comprises a display device electrically connected to the industrial control machine.

[0017] Preferably, a limit assembly is provided in a side wall of the box body close to the linear pulse testing device, and the limit assembly includes a steel ball, a support pin arranged on the top of the steel ball, and a locking spring sleeved on the top of the support pin. A plurality of arc-shaped positioning grooves are provided on the fork shaft, and the plurality of positioning grooves are arranged continuously from left to right, and the inner diameter of the positioning groove is greater than the outer diameter of the steel ball.

[0018] Preferably, the test workbench is provided with a plurality of brackets, and the installation box and the linear pulse test device are both installed on the brackets.

[0019] Preferably, the box body is detachably connected to a box cover.

[0020] Preferably, the limiting component is a locking nut threadedly connected to the gear shaft.

[0021] The beneficial effect of the present invention is that sensors are set at specific positions of the test equipment to test the theoretical shift force, theoretical reciprocating motion displacement, actual reciprocating motion displacement and actual shift force, so as to quickly verify the consistency between the design value and the actual value, thereby analyzing the specific factors or unreasonable parameter design of the reciprocating linear motion parts that lead to the final test failure, which is beneficial for designers to optimize.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structure of a reciprocating linear motion component life test device provided by the first embodiment of the present invention;

[0024] Figure 2 for Figure 1 An enlarged schematic diagram of the area "A" in the figure;

[0025] Figure 3 for Figure 1 Enlarged schematic diagram of point "B" in the figure.

[0026] Description of main component symbols:

[0027]

[0028]

[0029] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0030] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0031] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0033] See also Figures 1 to 3 , shown is a reciprocating linear motion component life test equipment in the first embodiment of the present invention, comprising a test bench 16, a mounting box arranged on the test bench 16, and a linear pulse test device connected to the other side of the mounting box, wherein:

[0034] The installation box includes a box body 7 and a box cover 10. The box cover 10 is detachably connected to the top of the box body 7, so as to facilitate the installation of various components in the box. A fork shaft 8 and a gear shaft 18 for installing reciprocating linear motion components are installed in the box body 7. Both ends of the gear shaft 18 are provided with limit components for limiting the installation position of the reciprocating linear motion components. The fork shaft 8 is provided with a fork 9 for shifting the reciprocating linear motion components to reciprocate linear motion. Specifically, the fork 9 can be movably connected to the fork shaft 8, so as to facilitate the replacement of the fork components or similar functional components corresponding to different reciprocating linear motion components.

[0035] The linear pulse test device includes a linear pulse generator 2, a force sensor 3, and a first displacement sensor 4. The linear pulse generator 2 is connected to the gear shaft 18 via an input shaft 11 to drive the fork shaft 8 to move linearly back and forth. The force sensor 3 is used to measure the theoretical shifting force applied by the linear pulse generator 2 to the fork shaft 8. The theoretical shifting force is equal to the designed shifting force, that is, the force applied by the linear pulse generator 2 to the fork shaft 8 is adjusted according to the designed shifting force; the first displacement sensor 4 is used to measure the theoretical reciprocating displacement applied by the linear pulse generator 2 to the fork shaft 8. The theoretical reciprocating displacement is equal to the designed reciprocating displacement, that is, the reciprocating displacement applied by the linear pulse generator 2 to the fork shaft 8 is adjusted according to the designed reciprocating displacement; in addition, a second displacement sensor 17 for measuring the actual reciprocating displacement of the fork 9 is provided at the position where the fork 9 is located; a pressure sensor for measuring the actual shifting force of the reciprocating linear motion component is provided on the limiting component. The limiting component is a locking nut threadedly connected to the gear shaft 18, specifically as shown in FIG. Figure 3As shown, the two limiting components are locking nut A19 and locking nut B27, and the pressure sensor provided on locking nut A19 is set as pressure sensor A21, and the pressure sensor provided on locking nut B27 is set as pressure sensor B25. Specifically, the first displacement sensor 4 and the force sensor 3 can be provided on the input shaft 11 to measure the theoretical reciprocating displacement and the theoretical shifting force; or the first displacement sensor 4 and the force sensor 3 can also be connected to the linear pulse generator 2 to obtain the theoretical reciprocating displacement and the theoretical shifting force from the linear pulse generator 2.

[0036] Specifically, the input shaft 11 is connected to the fork shaft 8 via a connecting member. The connecting member includes a connecting sleeve 6 and a flange 5 connected to each other, one of which is arranged at the end of the input shaft 11 and the other is arranged at the end of the fork shaft 8.

[0037] In addition, the reciprocating linear motion component life test equipment also includes an industrial computer 1 and a display device 31 electrically connected to the industrial computer 1. The industrial computer 1 is electrically connected to the force sensor 3, the first displacement sensor 4, the pressure sensor and the second displacement sensor 17, respectively, so as to collect the parameters collected by each sensor and display them through the display device 31.

[0038] A limit assembly is provided in one side wall of the box 7 near the linear pulse test device. The limit assembly includes a steel ball 28, a support pin 29 fixedly arranged on the top of the steel ball 28, and a locking spring 30 sleeved on the top of the support pin 29. A through hole 13 is provided on the inner wall of the box 7. The support pin 29 is slidably arranged in the through hole 13. The locking spring 30 is used to push the support pin 29 downward to reset the support pin 29, so that the steel ball 28 can float up and down. A plurality of arc-shaped positioning grooves 12 are provided on the fork shaft 8. The plurality of positioning grooves 12 are arranged successively from left to right. Preferably, the inner diameter of the positioning groove 12 is greater than the outer diameter of the steel ball 28. Specifically, there are multiple positioning grooves 12. When the fork shaft 8 reciprocates to a set position (e.g., a gear position), the steel ball 28 falls into the positioning grooves 12 at the corresponding positions, respectively, so as to buffer and limit the fork shaft 8. For example, when the fork shaft 8 moves to the left extreme position, the steel ball 28 falls into the left positioning groove 12; when the fork shaft 8 moves to the right extreme position, the steel ball 28 falls into the right positioning groove 12. Since the positioning groove 12 is arc-shaped, the steel ball 28 can still slide out of the positioning groove 12 when it falls into the positioning groove 12, and the inner diameter of the positioning groove 12 is larger than the outer diameter of the steel ball 28, so that when the reciprocating displacement changes (generally fine-tuning), the steel ball 28 can still cooperate with the positioning groove 12.

[0039] In addition, a plurality of brackets 15 are provided on the test workbench 16 , and the mounting box and the linear pulse test device are mounted on the brackets 15 .

[0040] The following is an example of the life test of the 3 / 4 gear shift fork of a certain type of transmission, and combined with the attached Figure 1-3 A specific implementation of the present invention is described below.

[0041] The synchronizer gear sleeve 23, the 3rd gear 24 and the 4th gear 23 are installed on the gear shaft 18. The 3rd gear 24 and the 4th gear 23 are installed on the gear shaft 18 and can slide left and right. The sizes of L4 and L7 are adjusted by the locking nut A19 and the locking nut B27 to achieve the adjustment of the design size and limit size position of L6 of the head of the shift fork 9 and the tooth groove width L5 of the synchronizer gear sleeve 23; the gear shaft 18 is installed on the housing 7 through bearings 14 at both ends, the shift fork 9 is installed on the shift fork shaft 8, and the shift fork shaft 8 and the gear shaft 18 are installed on the housing 7 according to the orientation of the transmission assembly.

[0042] Among them, the theoretical shift force F applied to the fork shaft 8 by the pulse test bench is measured by the force sensor 3, the theoretical reciprocating displacement S (L1 + L2) of the reciprocating motion is measured by the first displacement sensor 4, due to the manufacturing error and installation error of the parts and the movement impact of the fork 9, the actual reciprocating displacements L1 and L2 of the fork 9 are measured by the second position sensor, the shift force F4 of the fourth gear 22 is measured by the pressure sensor A21, and the shift force F3 of the third gear 24 is measured by the pressure sensor B25. The test signals of all sensors enter the industrial control box, see Figure 2 .

[0043] Test implementation steps:

[0044] 1) Analysis of the function, force, displacement and design value of the 3 / 4 gear shift fork 9

[0045] The function of the 3 / 4 gear shift fork 9 is to move left and right at three fixed positions: the third gear, neutral gear and the fourth gear through the locking mechanism of the shift shaft: the locking spring 30, the support pin 29 and the steel ball 28, and its reciprocating displacement S=L1+L2 is fixed, thereby pushing the synchronizer gear sleeve 23 to connect the third gear gear 24 or the fourth gear gear 22 to achieve different speeds of the vehicle. And the locking mechanism also prevents the synchronizer gear sleeve 23 from reversing due to inertia during operation.

[0046] Assume that the displacement of reciprocating motion S=(L1+L2), the shifting force of reciprocating motion is the design value F=F0, and the axial position of the 3 / 4 gear 23 and the synchronizer in the transmission is fixed (except for this device). However, due to the existence of design and manufacturing errors and installation errors, as well as running wear, if the synchronizer groove width L5 is too small, the fork 9 head L6 is too large, the synchronizer gear sleeve 23 is too large, and the 3 / 4 gear 23 size L9 is too small, the shifting may not be smooth, interference may occur, and the actual shifting force may be larger than the actual value; if the synchronizer groove width L5 is too large, the fork 9 head L6 is too small, the synchronizer gear sleeve 23 is too small, and the 3 / 4 gear 23 size L9 is too large, the shifting may not be in place, the operation may be reversed, and the actual shifting force may be smaller than the design value.

[0047] Therefore, the device can adjust the locking nuts A19 (19) and the locking nuts B27 (27) on both sides of the 3 / 4 gear 23 to measure the design shift force values ​​of the L4 locking the 4th gear 22 or the L7 locking the 3rd gear 24 at different shifting positions: middle difference, upper and lower deviations, limit deviations and super limit deviations, and the shifting position of the synchronizer, thereby verifying whether the design value of the shift force of the components is in line with the actual situation, the rationality of the design value of the limit deviation of the design size and the limit value of wear failure.

[0048] Assume that the design calculation is: the gear shift force of the transmission ball head is 200N, and the gear shift force from the gear shift mechanism to the fork shaft 8 is F0=1000N, but in reality, F=1200N may be required to smoothly shift gears (or F=900N). This may indicate that there is a calculation problem in the design of the parts, and there is a problem in designing the gear shift force to be F0=1000N. It is impossible to accurately verify the life of the gear shift fork 9 when using F=1000N for the actual test. The same verification problem also exists for the size limit.

[0049] 3) Based on the verified and confirmed shift force, dimensional displacement and wear limit values, design a durability life test procedure for the shift fork 9 and set an alarm shutdown limit.

[0050] 4) Start the test, observe the test operation, check the test operation data and charts, until the test operation alarm stops, confirm the test completion status or problems in the operation.

[0051] The whole test method is divided into three parts:

[0052] 1) Functional analysis of components: Through force analysis and combining the force transmission and friction resistance between components, find out or confirm whether the design value of the component is consistent with the actual value;

[0053] 2) Failure analysis of components: The displacement of reciprocating linear motion components is limited during reciprocating operation, and the wear and tear between components due to friction resistance and the damage caused by impact force during operation lead to cracks or fractures of components. Design the test method and test parameters of specific components or adjust the test parameter values ​​in the test method according to the verification results;

[0054] 3) Determination of design values ​​and test data related to the life of reciprocating parts.

[0055] The design load force F0, reciprocating motion displacement S0, operating cycle speed V0 and service life design value (or setting value) N0 of the parts determine the test pulse load force F, reciprocating motion displacement S, operating cycle speed V (or cycle frequency f), number of cycles N, wear limit value (displacement limit value and force limit value) and cycle completion value.

[0056] The pulse load force F, the reciprocating displacement S, the operating pulse frequency f, the number of cycles N and the alarm limit value of the test parameters mentioned above are determined as follows:

[0057] ⑴. Pulse load force F: Verified by design load force F0, that is, F = F0;

[0058] ⑵. Displacement S of reciprocating motion: verified by design displacement S0, i.e. S=S0;

[0059] ⑶. Operation pulse frequency f: directly use f=5Hz~10Hz or f=f0;

[0060] (4) Number of cycles N: according to the designed number of cycles N0, that is, N=N0.

[0061] And according to the relationship between the load force F0 and the design displacement S0 specified in the design and the error range, the limit alarm threshold and the test completion: N=N0+1 alarm shutdown value are set.

[0062] System test equipment, see Figure 1 The device includes an impulse test bench that provides reciprocating linear motion, a component mounting device, and an intelligent testing system.

[0063] The reciprocating linear motion pulse test bench is a general-purpose device. The parameter range and accuracy requirements of the pulse test bench can be selected according to the design parameter range and test requirements of the reciprocating motion category components, including the functional requirements met by the test bench.

[0064] The component installation device needs to be designed and manufactured according to the specific test components, which is the focus of the test device of the present invention.

[0065] In summary, the reciprocating linear motion component life test equipment in the above-mentioned embodiment of the present invention sets sensors at specific positions of the test equipment to test the theoretical shifting force, theoretical reciprocating motion displacement, actual reciprocating motion displacement and actual shifting force, so as to quickly verify the consistency between the design value and the actual value, thereby analyzing the specific factors or unreasonable parameter design of the reciprocating linear motion component that caused the final test failure, which is beneficial for designers to optimize.

[0066] The above-mentioned embodiment only expresses one implementation mode of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A life test equipment for reciprocating linear motion parts, characterized in that: The invention comprises a test bench, an installation box arranged on the test bench, and a linear pulse test device connected to the other side of the installation box, wherein the installation box comprises a box body, a fork shaft and a gear shaft for installing a reciprocating linear motion component are installed in the box body, both ends of the gear shaft are provided with a limit component for limiting the installation position of the reciprocating linear motion component, and the fork shaft is provided with a fork for shifting the reciprocating linear motion component to reciprocate linear motion; The linear pulse test device comprises: A linear pulse generator connected to the gear shaft via an input shaft to drive the fork shaft to reciprocate linearly; A force sensor for measuring a theoretical shifting force applied by the linear pulse generator to the shift fork shaft; a first displacement sensor, measuring the theoretical reciprocating displacement applied to the fork shaft by the linear pulse generator; In addition, a second displacement sensor for measuring the actual reciprocating displacement of the shift fork is provided at the position where the shift fork is located; The limiting component is provided with a pressure sensor for measuring the actual shifting force of the reciprocating linear motion component; The input shaft is connected to the shift fork shaft via a connecting piece; The reciprocating linear motion component life test equipment also includes an industrial computer, and the industrial computer is electrically connected to the force sensor, the first displacement sensor, the pressure sensor and the second displacement sensor respectively.

2. The reciprocating linear motion component life test equipment according to claim 1, characterized in that: The connecting member comprises a connecting sleeve and a flange plate which are connected to each other. One of the connecting sleeve and the flange plate is arranged at the end of the input shaft, and the other is arranged at the end of the shift fork shaft.

3. The reciprocating linear motion component life test equipment according to claim 1, characterized in that: The reciprocating linear motion component life test equipment also includes a display device electrically connected to the industrial control machine.

4. The reciprocating linear motion component life test equipment according to claim 1, characterized in that: A limit assembly is provided in a side wall of the box body close to the linear pulse test device, and the limit assembly includes a steel ball, a support pin arranged on the top of the steel ball, and a locking spring sleeved on the top of the support pin. A plurality of arc-shaped positioning grooves are provided on the fork shaft, and the plurality of positioning grooves are arranged continuously from left to right, and the inner diameter of the positioning groove is greater than the outer diameter of the steel ball.

5. The reciprocating linear motion component life test equipment according to claim 1, characterized in that: The test workbench is provided with a plurality of brackets, and the installation box and the linear pulse test device are both installed on the brackets.

6. The reciprocating linear motion component life test equipment according to claim 1, characterized in that: The box body is detachably connected to a box cover.

7. The reciprocating linear motion component life test equipment according to any one of claims 1 to 6, characterized in that: The limiting component is a locking nut threadedly connected to the gear shaft.

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