CN215866120U - Rubber wheel grounding trace test fixture for laboratory friction and abrasion test - Google Patents
Rubber wheel grounding trace test fixture for laboratory friction and abrasion test Download PDFInfo
- Publication number
- CN215866120U CN215866120U CN202122086409.8U CN202122086409U CN215866120U CN 215866120 U CN215866120 U CN 215866120U CN 202122086409 U CN202122086409 U CN 202122086409U CN 215866120 U CN215866120 U CN 215866120U
- Authority
- CN
- China
- Prior art keywords
- test
- fixing
- rubber wheel
- clamp
- positioning
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The utility model belongs to the technical field of performance test equipment, and particularly relates to a test fixture for a rubber wheel grounding trace of a laboratory friction abrasion test, which comprises an upper fixture and a lower fixture, wherein the set of fixture can be arranged on a universal tester, and the test rubber wheel coated with ink paste is pressed onto a road surface wheel for placing coordinate paper at a certain pressure by utilizing the characteristic that the universal tester can provide force values and displacement, so that the contact trace of the test rubber wheel and the road surface wheel under a certain pressure and a certain angle is obtained. The clamp provided by the utility model can be used for testing the ground pressure of the test rubber wheel of different experimental projects in the experimental process, establishes correlation with the ground pressure of the tire and guides and explores the reasonability of the setting of experimental conditions, so that the experimental result can better reflect the formula and the wear resistance of the tire.
Description
Technical Field
The utility model belongs to the technical field of performance test equipment, and particularly relates to a rubber wheel grounding trace test fixture for a laboratory friction wear test.
Background
The tire is the only part of the automobile contacting with the ground, the friction force between the tire and the ground plays an important role in the starting, driving and braking processes of the automobile, and meanwhile, the wear resistance of the tire is an important index for evaluating the service life of the tire. In the development of laboratory tire formulations, the abrasion resistance of the rubber compound is generally evaluated by simulating the running state of the tire through an Akron abrasion tester, a Lambertan abrasion tester and the like. In the parameter setting process, the parameters such as load, speed, angle, slip ratio and the like can be directly set through an instrument, but the contact pressure of the rubber wheel and the road surface cannot be set, and the parameters can only be obtained through the calculation of the ratio of the load to the grounding area. Since the grounding pressure parameter is a key index for evaluating the performance of the rubber material in the actual running process of the tire simulated in a laboratory, the area of the rubber wheel and the contact surface under a certain load is tested to calculate the grounding pressure of the rubber wheel, and the method is an important work for judging whether the set parameter is representative. At present, the tire footprint test has instruments and standards, and no test method is found for the contact patches of rubber wheels and road wheels of a laboratory abrasion tester.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the problems in the prior art, fill the blank in the technical aspect, and provide a test fixture for the ground contact mark of a rubber wheel for a laboratory friction and abrasion test.
The technical scheme of the utility model is as follows:
a rubber wheel footprint test fixture for a laboratory friction wear test comprises an upper fixture and a lower fixture,
the upper clamp comprises an inverted U-shaped sample frame, a first positioning pin and a second fixing nut, the first positioning pin and the second fixing nut are respectively and symmetrically arranged on two side plates of the sample frame, and the first positioning pin penetrates through one side plate of the sample frame and is connected with the second fixing nut arranged on the other side plate;
the lower clamp is one of a first lower clamp or a second lower clamp, wherein,
the first lower clamp comprises an angle positioning disc, an angle adjusting disc and a road wheel tray are sequentially arranged on the angle positioning disc, and a road wheel baffle plate for mounting a road wheel is arranged on the road wheel tray; the road wheel tray is fixedly installed on the angle adjusting disc, a first fixing screw is installed on the angle adjusting disc, and the first fixing screw penetrates through the angle adjusting disc and is fixedly connected with the angle positioning disc.
The lower fixture comprises a plane testing surface.
Furthermore, a test rubber wheel is installed between the two side plates of the sample frame, the test rubber wheel is sleeved on the first positioning pin, test rubber wheel baffles are installed on two sides of the test rubber wheel respectively, and the first positioning pin penetrates through the test rubber wheel and the test rubber wheel baffles and fixes the test rubber wheel and the test rubber wheel baffles.
Further, the upper clamp further comprises a first fixing column and a first fixing nut, and the lower end of the first fixing column penetrates through the U-shaped bottom end of the inverted U-shaped sample rack and is fixedly connected with the first fixing nut; the sample rack is characterized in that a through hole for mounting a second positioning pin is formed in the position where the first fixing column is connected with the sample rack, a first positioning hole is formed in the upper end of the first fixing column, and the second positioning pin and the first positioning hole are located on the same central line.
Further, go up anchor clamps and still include first solid fixed ring, first solid fixed ring cover is established on the first fixed column, and is located between first locating hole and the second locating pin.
Furthermore, an arc-shaped through hole is formed in the angle adjusting disc, and the first fixing screw penetrates through the arc-shaped through hole and is fixed on the angle positioning disc; the angle scale is installed on the angle positioning plate and does not overlap with the angle adjusting plate.
Further, the first lower clamp further comprises a second fixing column, and the angle positioning disc is mounted on the second fixing column; the road wheel tray is fixedly arranged on the angle adjusting disc through a second fixing screw; the road wheel baffle is provided with a third fixing screw for fixedly mounting a road wheel; and the angle positioning plate and the second fixing column are fixedly installed through a fourth fixing screw.
Furthermore, a second fixing ring is sleeved on the second fixing column, and a second positioning hole is formed in the lower end of the second fixing column.
Further, the test surface is of a platform structure, the test surface is fixedly mounted on a third fixing column, a third fixing ring is sleeved on the upper end of the third fixing column, and a third through positioning hole is formed in the center of the lower end of the third fixing column.
Further, the clamp is made of any one of metal, ceramic or solid wood.
The utility model has the beneficial effects that:
(1) the clamp provided by the utility model can be used for testing the ground pressure of test rubber wheels (such as Akron abrasion, Lamberten abrasion and the like) of different experimental projects in the experimental process, establishes correlation with the ground pressure of tires, and guides and explores the reasonability of the setting of experimental conditions, so that the experimental result can better reflect the formula and the wear resistance of the tires.
(2) The clamp provided by the utility model is used as an experimental clamp, is connected with a universal testing machine, is convenient to test, and develops the testing function of the universal testing machine; through changing experimental rubber tyer baffle and experimental rubber tyer, can realize different experimental projects, not unidimensional experimental rubber tyer and road surface wheel between ground connection area to obtain pressure, test expansibility is strong.
(3) The utility model provides two types of lower clamps which can be matched with the upper clamp for use; the lower clamp I is adopted to adjust the test angle at will, so that the grounding areas between the test rubber wheels and the road wheels under different loads and different angles are obtained; and the lower clamp II provides a platform test surface, so that the impression test experiment under different loads can be carried out.
Drawings
FIG. 1 is a front view of an upper fixture with a test rubber wheel installed in accordance with the present invention;
FIG. 2 is a schematic perspective view of an upper fixture with a rubber wheel for testing according to the present invention;
FIG. 3 is a cross-sectional view of the upper fixture with a test rubber wheel installed in accordance with the present invention;
FIG. 4 is a schematic perspective view of a first lower clamp provided with road wheels according to the present invention;
FIG. 5 is a right side view of a first road wheel mounted lower clamp according to the present invention;
FIG. 6 is a cross-sectional view A-A of FIG. 5 in accordance with the present invention;
FIG. 7 is a schematic perspective view of a second lower clamp provided with road wheels according to the present invention;
FIG. 8 is a schematic diagram of the imprint obtained by the test in the experimental example of the present invention;
in the above figures, 1, a first fixed column; 2. a first retaining ring; 3. a sample holder; 4. a first fixing nut; 5. a first positioning pin; 6. testing rubber wheel baffle plates; 7. testing the rubber wheel; 8. a second fixing nut; 9. a second positioning pin; 10. a first positioning hole; 11. a road wheel; 12. road wheel baffles; 13. a road wheel tray; 14. an angle adjusting disk; 15. an angle scale; 16. an angle positioning plate; 17. a second retaining ring; 18. a second fixed column; 19. a second positioning hole; 20. a first set screw; 21. a second set screw; 22. a third set screw; 23. a fourth set screw; 24. testing the surface; 25. a third fixing ring; 26. a third fixing column; 27. and a third positioning hole.
Detailed Description
The utility model is further described below with reference to the figures and examples.
In the description of the present invention, it should be noted that the terms "upper", "lower", "center", and the like indicate orientations or positional relationships based on positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The clamp provided by the utility model comprises an upper clamp and a lower clamp which are combined for use and have improved structures, wherein the lower clamp comprises two structure types, and one structure type is selected to be matched with the upper clamp for use. The clamp is used for testing contact marks of a test rubber wheel and a road wheel under certain pressure in a laboratory abrasion test; wherein, go up the anchor clamps and fix the experimental rubber tyer that has scribbled the ink paste on universal machine's sensor, lower anchor clamps (anchor clamps one or anchor clamps two down, select according to experimental needs) fix the road surface wheel on universal machine base, place the coordinate paper on road surface wheel (or the test surface of anchor clamps two down), utilize universal machine with certain speed and power value will test the rubber tyer and press the road surface wheel on, just can be with the area of contact of experimental rubber tyer and road surface wheel printed on the coordinate paper through the ink paste of experimental rubber tyer, thereby obtain the ground connection impression of experimental rubber tyer.
The clamp is made of solid materials such as different metals, ceramics or solid wood, and other suitable materials can be selected by the technical personnel in the field according to the actual test requirements.
The following is an explanation by means of two specific examples.
Example 1
As shown in fig. 1 to 6, the present embodiment relates to a test fixture for contact patch of rubber wheel in laboratory friction wear test, which comprises an upper fixture and a lower fixture, and the fixture is used for testing contact patches of rubber wheel and road wheel in laboratory friction wear test under certain pressure and certain angle. The set of clamp is divided into an upper clamp and a lower clamp, the upper clamp is used for fixing the test rubber wheel on a sensor of the universal testing machine, and the lower clamp is used for fixing the road wheel on a base of the universal testing machine.
The upper clamp comprises an inverted U-shaped sample frame, a first positioning pin and a second fixing nut, a first fixing column is mounted at the upper end of the inverted U-shaped sample frame, and the lower end of the first fixing column penetrates through the sample frame and then is fixedly connected with the first fixing nut; the position that meets with the sample frame on the first fixed column is equipped with the through-hole that is used for installing the second locating pin, and first fixed column upper end is equipped with first locating hole, and second locating pin and first locating hole are located same central line. Namely, the first fixing column of the upper clamp and the sample frame are installed together through the first fixing nut, and the second positioning pin is installed at the central positions of the sample frame and the first fixing column and is located on the same central line with the first positioning hole.
The first positioning pin and the second fixing nut are symmetrically arranged on two side plates of the sample rack respectively, and the first positioning pin penetrates through the side plate on one side of the sample rack and is connected with the second fixing nut arranged on the side plate on the other side. Furthermore, a test rubber wheel is arranged between two side plates of the sample frame, the test rubber wheel is sleeved on a first positioning pin, test rubber wheel baffles are respectively arranged on two sides of the test rubber wheel, and the first positioning pin penetrates through the test rubber wheel and the test rubber wheel baffles and fixes the test rubber wheel and the test rubber wheel baffles. And the test rubber wheel and the second fixing nut are arranged on the sample frame after being loaded with a test sample.
Furthermore, the upper clamp further comprises a first fixing ring, the first fixing ring is sleeved on the first fixing column and is located between the first positioning hole and the second positioning pin. The upper clamp is connected with a sensor of the universal testing machine through a first fixing column, and the upper clamp is fixed through a first positioning hole and a first fixing ring matched with a positioning pin of the universal testing machine.
And the lower clamp I is fixed together by the angle positioning plate and the second fixing column through a fourth fixing screw. The angle positioning disc is sequentially provided with an angle disc, an angle adjusting disc and a road wheel tray, and the road wheel tray is provided with a road wheel baffle plate for mounting a road wheel; road wheel tray fixed mounting is on angle adjustment dish, installs first set screw on the angle adjustment dish, and first set screw runs through angle adjustment dish and with angle positioning dish rigid coupling.
The road wheel tray is installed together with the angle adjusting disc through a second fixing screw, wherein an arc-shaped through hole is formed in the angle adjusting disc, and the first fixing screw penetrates through the arc-shaped through hole and is fixed on the angle positioning disc; through the elasticity of adjusting first set screw, can realize that angle adjustment dish rotates on angle positioning dish, realize different test angles. The angle scale is fixed on one side of the angle positioning plate, and when the angle scale is shifted by 0 degree, the marked lines on the angle adjusting plate should be aligned with the 0-degree scale lines of the angle scale.
The road wheel tray is fixedly arranged on the angle adjusting disc through a second fixing screw; and the road wheel baffle is provided with a third fixing screw for fixedly mounting the road wheel, and the road wheel baffle is detached and fixed through the tightness of the third fixing screw. And the angle positioning plate and the second fixing column are fixedly installed through a fourth fixing screw.
Furthermore, a second fixing ring is sleeved on the second fixing column, and a second positioning hole is formed in the lower end of the second fixing column. The whole set of lower fixture I is connected with a bottom flange interface of the universal testing machine through a second fixing column, and is fixed through a second positioning hole and a second fixing ring matched with a positioning pin of the universal testing machine.
The use method of the clamp in the embodiment comprises the following steps:
(1) go up the anchor clamps and link to each other through first fixed column and universal tester's sensor, through first locating hole and first solid fixed ring and universal tester's locating pin, it is fixed firm to go up the anchor clamps. The test rubber wheel baffle is placed at two ends of the test rubber wheel, the first positioning pin penetrates through the centers of the sample frame, the test rubber wheel and the test rubber wheel baffle, the second fixing nut penetrates through the other end of the sample frame, and the thread at the front end of the first positioning pin is screwed into the thread of the second fixing nut, so that the test rubber wheel is tightly fixed on the sample frame. The test rubber wheel can be uniformly coated with inkpad on the surface before installation or after installation.
(2) The first lower clamp is connected with the bottom of the universal testing machine through a second fixing column, and is fixed through a second positioning hole and a second fixing ring which are matched with a positioning pin of the universal testing machine; loosening the third fixing screw, placing the road wheel to be tested on the road wheel tray, and screwing the third fixing screw until the road wheel baffle plate clamps the road wheel; at the moment, the first positioning hole, the second positioning hole, the test rubber wheel and the road wheel are on the same vertical line, and the marked line of the angle adjusting plate is aligned with the 0-degree scale line located on the angle scale.
(3) The method comprises the following steps of placing coordinate paper on a road wheel, setting a required test method, pressing the test rubber wheel on the road wheel after the test is started, finishing the test after a set load is reached, obtaining the actual contact area of the formula test rubber wheel and the road wheel under a certain load on the coordinate paper, observing and calculating through an electronic magnifier and other measurement methods, obtaining the corresponding pressure condition, and comparing the corresponding pressure condition with the actual tire working condition.
(4) If the angle test is needed, loosening the first fixing screw, manually rotating the road wheel, rotating the road wheel tray and the angle adjusting disc together, rotating the road wheel tray to drive the angle adjusting disc to rotate, driving the angle adjusting disc to rotate until the marked line is aligned with the required scale to complete angle adjustment (the angle adjusting range is 40 degrees in the clockwise direction and the anticlockwise direction, the angle range depends on the range and specific use of the angle disc), screwing the first fixing screw, and then completing the angle adjustment; an included angle is formed between the test rubber wheel and the road wheel, and the test process is repeated.
Example 2
As shown in fig. 1 to 3 and fig. 7, the present embodiment relates to a rubber wheel footprint testing jig for a laboratory friction wear test, which includes an upper jig and a second lower jig, and the difference between the present embodiment 2 and the embodiment 1 is that the structure of the lower jig is different, and the second lower jig is selected to be used in combination with the upper jig in the present embodiment.
The lower clamp II consists of a test surface, a third fixing ring and a third fixing column, and a third positioning hole is formed in the lower end of the third fixing column; the third fixing column is placed in a flange interface at the bottom of the universal testing machine, and the third fixing column is fixed by matching a third positioning hole and a third fixing ring with a positioning pin of the universal testing machine.
The using method comprises the following steps:
fixing the second lower clamp on a universal testing machine, placing coordinate paper on a testing surface, installing a sample to be tested (namely a testing rubber wheel) on a sample rack according to the method of the embodiment 1, smearing inkpad, and starting testing; after the test is finished, the required test impression is obtained on the coordinate paper.
Test examples
1. Instruments and materials
Universal testing machine: american instron 5969;
microscope: shenzhen, model ZW-H46800, a science and technology Limited;
coordinate paper and inkpad.
2. Sample (I)
Cloning test rubber wheel: three subclone test rubber wheels 1, 2, 3 were prepared with shore a hardness of 50, 55 and 73, respectively.
3. Test conditions
Conditions of the universal testing machine: the compression rate was 50mm/min and the load was measured 26.7N, 53.4N and 80.1N, respectively.
The included angle between the test rubber wheel and the road wheel is as follows: 0 ° and 15 ° were tested, respectively.
4. Test results
By using the experimental scheme of the utility model, the test of the imprints of the rubber wheel and the road wheel in the Akron test under different loads and angles is carried out, the area of the imprints is calculated by observing and measuring through a microscope after the test, and the results are shown in the detailed chart 8, the table 1 and the table 2.
TABLE 1 test results of the print areas of the rubber wheel and the road wheel in the Akron test under different loads
TABLE 2 Arch test rubber wheel and road wheel pressure under different loads
By analyzing the test data, it can be seen that the areas of contact between the Akron test rubber wheels with different hardness and the road wheel are different under the same load, so that the Akron test rubber wheels with different hardness have different pressures under the same load.
If the Akron test rubber wheels under the same pressure intensity need to be compared in the test process, different loads need to be set for different test rubber wheels in the Akron test process.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described above, or equivalents may be substituted for elements thereof without departing from the scope of the utility model. Any modification, equivalent replacement, or modification made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. A rubber wheel footprint test fixture for a laboratory friction wear test is characterized by comprising an upper fixture and a lower fixture,
the upper clamp comprises an inverted U-shaped sample frame, a first positioning pin and a second fixing nut, the first positioning pin and the second fixing nut are respectively and symmetrically arranged on two side plates of the sample frame, and the first positioning pin penetrates through one side plate of the sample frame and is connected with the second fixing nut arranged on the other side plate;
the lower clamp is one of a first lower clamp or a second lower clamp, wherein,
the first lower clamp comprises an angle positioning disc, an angle adjusting disc and a road wheel tray are sequentially arranged on the angle positioning disc, and a road wheel baffle plate for mounting a road wheel is arranged on the road wheel tray; the road wheel tray is fixedly arranged on the angle adjusting disc, a first fixing screw is arranged on the angle adjusting disc, and the first fixing screw penetrates through the angle adjusting disc and is fixedly connected with the angle positioning disc;
the lower fixture comprises a plane testing surface.
2. The fixture according to claim 1, wherein a test rubber wheel is mounted between two side plates of the sample holder, the test rubber wheel is sleeved on the first positioning pin, test rubber wheel baffles are respectively mounted on two sides of the test rubber wheel, and the first positioning pin penetrates through the test rubber wheel and the test rubber wheel baffles and fixes the test rubber wheel and the test rubber wheel baffles.
3. The clamp according to claim 1, wherein the upper clamp further comprises a first fixing column and a first fixing nut, and the lower end of the first fixing column penetrates through the U-shaped bottom end of the inverted U-shaped sample rack and is fixedly connected with the first fixing nut; the sample rack is characterized in that a through hole for mounting a second positioning pin is formed in the position where the first fixing column is connected with the sample rack, a first positioning hole is formed in the upper end of the first fixing column, and the second positioning pin and the first positioning hole are located on the same central line.
4. The clamp of claim 3, wherein the upper clamp further comprises a first fixing ring, the first fixing ring is sleeved on the first fixing column and is located between the first positioning hole and the second positioning pin.
5. The clamp of claim 1, wherein the angle adjusting plate is provided with an arc-shaped through hole, and the first fixing screw passes through the arc-shaped through hole and is fixed on the angle positioning plate; the angle scale is installed on the angle positioning plate and does not overlap with the angle adjusting plate.
6. The clamp of claim 1, wherein the first lower clamp further comprises a second fixed post, the angular positioning plate being mounted on the second fixed post; the road wheel tray is fixedly arranged on the angle adjusting disc through a second fixing screw; the road wheel baffle is provided with a third fixing screw for fixedly mounting a road wheel; and the angle positioning plate and the second fixing column are fixedly installed through a fourth fixing screw.
7. The clamp according to claim 6, wherein a second fixing ring is sleeved on the second fixing column, and a second positioning hole is formed in the lower end of the second fixing column.
8. The fixture according to claim 1, wherein the testing surface is a platform structure, the testing surface is fixedly mounted on a third fixing column, a third fixing ring is sleeved on an upper end of the third fixing column, and a third positioning hole penetrating through the third fixing ring is formed in a center of a lower end of the third fixing column.
9. A clamp as claimed in any one of claims 1 to 8, wherein the clamp is made of any one of metal, ceramic or solid wood.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122086409.8U CN215866120U (en) | 2021-08-31 | 2021-08-31 | Rubber wheel grounding trace test fixture for laboratory friction and abrasion test |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122086409.8U CN215866120U (en) | 2021-08-31 | 2021-08-31 | Rubber wheel grounding trace test fixture for laboratory friction and abrasion test |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215866120U true CN215866120U (en) | 2022-02-18 |
Family
ID=80244827
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122086409.8U Active CN215866120U (en) | 2021-08-31 | 2021-08-31 | Rubber wheel grounding trace test fixture for laboratory friction and abrasion test |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215866120U (en) |
-
2021
- 2021-08-31 CN CN202122086409.8U patent/CN215866120U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5900531A (en) | Portable universal friction testing machine and method | |
| CN215866120U (en) | Rubber wheel grounding trace test fixture for laboratory friction and abrasion test | |
| US5842281A (en) | Wheelless alignment apparatus and method of using same | |
| US4294111A (en) | Portable fluid ink tack tester | |
| CN113188889A (en) | Testing arrangement is glued to structure | |
| CN101482405B (en) | Curve example substrate coating thickness measuring method and sample clamping tool | |
| CA2231234A1 (en) | Portable tire uniformity measurement system and method | |
| US3423839A (en) | Apparatus for checking wheel alignment characteristics | |
| CN114199106B (en) | Mechanical meter counter inspection device | |
| CN112461150B (en) | Device and method for measuring strain of guide pipe for well drilling | |
| CN210243347U (en) | Flexible printed circuit board bending fatigue testing device | |
| CN210834615U (en) | Dynamic shear rheometer friction coefficient testing device | |
| CN2622666Y (en) | Clamp for checking automobile glass | |
| CN213631940U (en) | Centering measuring tool for motor shaft and sample tool shaft of electric rotating test bench | |
| CN219417209U (en) | Device for detecting color difference of paint film coating | |
| CN213301698U (en) | Device suitable for calibrating full-range dynamic sensor | |
| CN214277704U (en) | High-precision pavement material strength tester | |
| CN220650663U (en) | Putty flexibility tester | |
| CN214426899U (en) | Axial tensiometer tension test device | |
| CN220983390U (en) | Multi-specification carbon block resistivity tester | |
| CN213631863U (en) | Comprehensive inspection device for mounting position of gear selecting and shifting flexible shaft gearbox | |
| CN211317179U (en) | Simple tool for measuring attack angles of windscreen wipers with various specifications | |
| CN217654887U (en) | Positioning device of hardness detection instrument | |
| CN115077789B (en) | Simply supported force value sensor magnitude tracing device and calibration method | |
| CN218556766U (en) | Positioning device for detection of precision instrument |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |