Upper clamp and clamp assembly for testing tensile strength of short bolt
By designing a combination clamp of a conical snap ring and a test sleeve, the problem of unsatisfactory clamping of short bolts in tensile strength testing was solved, achieving more stable clamping and simpler installation, thus improving the accuracy of the test.
Patent Information
- Application Number
- CN202422883035.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-26
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-11-26
AI Technical Summary
Existing bolt tensile strength testing fixtures are not ideal for holding short bolts, leading to inaccurate testing.
A clamping fixture for testing the tensile strength of short bolts was designed, which uses a conical snap ring and a test sleeve. By setting screw holes and conical holes inside the sleeve, and equipping it with a clamping component and a rotating shaft, the snap ring is stably clamped, thus enhancing the clamping effect.
The clamping effect of the screw of the short bolt by the lower clamp is improved, ensuring the accuracy and stability of the test and simplifying the installation process.
Smart Images
Figure CN223551456U_ABST
Abstract
Description
Technical Field
[0001] This application relates to bolt tensile strength testing technology, and more particularly to an upper clamp and clamp assembly for testing the tensile strength of short bolts. Background Technology
[0002] In industrial manufacturing, the tensile strength of bolts is one of the important parameters for evaluating their performance and reliability. Bolt tensile strength test fixtures are important tooling fixtures for testing the tensile strength of bolts.
[0003] Reference Figure 1 The existing bolt tensile strength test fixture includes an upper clamp 1 and a locking seat 2. The upper clamp 1 includes a clamping seat 11 and a mounting stud 12 installed on the top of the clamping seat 11. The outer wall of the clamping seat 11 has an arrangement chamber 13 and an arrangement through hole 14 connecting the lower end of the arrangement chamber 13 and the bottom surface of the clamping seat 11. The connection between the arrangement chamber 13 and the arrangement through hole 14 forms a limiting surface 15 for the locking seat 2 to abut against. The steps for installing the bolt to be tested onto the above-mentioned bolt tensile strength test fixture are as follows: First, the locking seat 2 is sleeved on the bolt to be tested, so that the locking ring 4 abuts against the bolt head of the bolt to be tested; then, the locking seat 2 and the bolt to be tested are placed in the arrangement chamber 13 of the clamping seat 11, so that the locking seat 2 abuts against the limiting surface 15.
[0004] However, when conducting tensile strength tests on short bolts, due to the short length of the bolt shank, the bolt shank extends only a short distance beyond the test fixture when using the upper clamp for the bolt tensile strength test, resulting in an unsatisfactory clamping effect of the bolt shank being held by the lower clamp. Utility Model Content
[0005] To improve the clamping effect of the lower clamp on the screw of a short bolt, this application provides an upper clamp and clamp assembly for testing the tensile strength of a short bolt.
[0006] Firstly, the upper clamp for testing the tensile strength of short bolts provided in this application adopts the following technical solution:
[0007] A clamp for testing the tensile strength of short bolts includes a test sleeve, a retaining ring, and a connector. The retaining ring is conical and has a retaining through hole that extends through the upper and lower surfaces for the threaded rod of the bolt to be tested to pass through. The connector includes a mounting post and an upper stud connected to the top of the mounting post. The top surface of the test sleeve has a threaded hole for threaded installation of the mounting post. The test sleeve also has a conical hole that connects the bottom surface of the threaded hole and the bottom surface of the test sleeve for the retaining ring to be arranged. The threaded hole includes a smooth section and a threaded section from bottom to top.
[0008] By adopting the above technical solution, the snap-fit ring is sleeved on the bolt to be tested, and the snap-fit ring and the bolt to be tested are placed into the arrangement screw hole of the test sleeve, so that the bolt of the bolt to be tested passes through the snap-fit through hole of the snap-fit ring and the arrangement tapered hole at the bottom of the test sleeve at the same time. The tapered shape of the snap-fit ring allows the tapered surface of the snap-fit ring to fit against the tapered surface of the arrangement tapered hole when the snap-fit ring is placed in the arrangement tapered hole, so that the top surface of the snap-fit ring is flush with the top surface of the arrangement tapered hole. This reduces the distance between the top surface of the snap-fit ring and the bottom surface of the test sleeve when the snap-fit ring is placed in the test sleeve, thereby improving the clamping effect of the short bolt bolt by the lower clamp.
[0009] Optionally, a clamping assembly is provided between the mounting post and the snap ring; the clamping assembly includes a first baffle abutting against the mounting post, a second baffle abutting against the top surface of the snap ring, and a clamping spring arranged between the first baffle and the second baffle; the bottom surface of the second baffle has an annular protrusion arranged circumferentially for clamping the snap ring.
[0010] By adopting the above technical solution, the clamping component is designed so that when the mounting post is screwed into the arrangement screw hole, the first baffle moves downward, thereby compressing the clamping spring. The annular protrusion allows the second baffle to press the snap ring into the arrangement cone hole under the action of the clamping spring, which helps to improve the stability of the snap ring when it is arranged in the arrangement cone hole.
[0011] Optionally, the maximum diameter of the arrangement conical hole is smaller than the diameter of the arrangement screw hole, and the test sleeve forms a limiting annular surface at the connection between the arrangement screw hole and the arrangement conical hole; the inner side of the bottom surface of the annular protrusion is pressed against the snap ring and the outer side of the bottom surface of the annular protrusion is pressed against the limiting annular surface.
[0012] By adopting the above technical solution, when the second baffle presses the snap ring into the arrangement cone hole, the cooperation between the limiting ring surface and the annular protrusion allows the top of the snap ring to be flush with the limiting ring surface, which helps to make the snap ring ideally stable in the arrangement cone hole.
[0013] Optionally, the outer diameter of the annular protrusion is adapted to the inner diameter of the smooth section of the screw hole.
[0014] By adopting the above technical solution, when the second baffle moves within the smooth section where the screw holes are arranged, the probability of interference between the annular protrusion of the second baffle and the smooth section where the screw holes are arranged can be reduced.
[0015] Optionally, a limiting groove is formed on the bottom surface of the mounting column, and the top surface of the first baffle is an arc-shaped surface that abuts against the bottom surface of the limiting groove.
[0016] By adopting the above technical solution, the combination of the limiting groove and the arc-shaped surface reduces the contact area between the mounting post and the first baffle, thereby helping to reduce the friction between the mounting post and the first baffle, making it easier for the mounting post to be screwed into the arrangement screw hole.
[0017] The curved surface design allows the top surface of the first baffle to abut against the limiting groove on the bottom surface of the mounting column when the mounting column rotates, which helps to keep the first baffle horizontal.
[0018] Optionally, the upper stud is provided with a radially extending first insertion hole and a rotating shaft is detachably mounted at the first insertion hole; the rotating shaft has an insertion end for engaging with the first insertion hole and a holding end away from the insertion end.
[0019] By adopting the above technical solution, the cooperation between the first insertion hole and the rotating shaft allows the operator to drive the upper stud to rotate by holding the end, thereby making it easier to screw the mounting post of the connector into the threaded section of the screw hole.
[0020] Optionally, the rotating shaft has a plunger hole on the outer side wall of the insertion end and a ball spring plunger is installed in the plunger hole; the upper stud has a snap-fit ring groove on the inner wall of the first insertion hole for the plunger ball of the ball spring plunger to snap into.
[0021] By adopting the above technical solution, the cooperation between the plunger roller and the retaining ring groove of the ball spring plunger makes it less likely for the rotating shaft to move when it is installed in the first socket, which helps to reduce the probability that the rotating shaft will come out of the first socket when the operator rotates the upper stud.
[0022] Optionally, the rotating shaft is fitted with an anti-slip sleeve at the gripping end, and the outer surface of the anti-slip sleeve is provided with anti-slip texture.
[0023] By adopting the above technical solutions, the anti-slip sleeve and anti-slip texture help to improve the anti-slip performance of the grip end.
[0024] Optionally, the angle between the outer conical surface of the snap ring and the large end face of the snap ring is 30° to 50°.
[0025] Secondly, the fixture assembly for testing the tensile strength of short bolts provided in this application adopts the following technical solution:
[0026] A fixture assembly for testing the tensile strength of short bolts includes a lower fixture and an upper fixture for testing the tensile strength of short bolts.
[0027] In summary, this application includes at least one of the following beneficial technical effects:
[0028] An upper clamp for testing the tensile strength of short bolts is provided. By setting the snap-fit ring as a cone and opening a screw hole in the test sleeve and a conical hole connecting the bottom surface of the screw hole and the bottom surface of the test sleeve, when the snap-fit ring is placed in the conical hole, the conical surface of the snap-fit ring fits against the conical surface of the conical hole, thereby reducing the distance between the top surface of the snap-fit ring and the bottom surface of the test sleeve, and increasing the length of the bolt extending from the bottom of the test sleeve, thereby improving the clamping effect of the bolt of the short bolt by the lower clamp.
[0029] By setting a clamping assembly between the mounting post and the snap ring, the annular protrusion of the second baffle can press the snap ring into the arrangement cone hole and the top surface of the snap ring is flush with the limiting ring surface.
[0030] By providing a first insertion hole on the upper stud and detachably mounting a rotating shaft at the first insertion hole, it is easier for the operator to screw the mounting post of the connector into the arrangement screw hole.
[0031] A fixture assembly for testing the tensile strength of a short bolt includes an upper fixture and a lower fixture. When the bolt to be tested is arranged in the arrangement cone hole of the test sleeve and the bolt shank of the bolt to be tested extends to the bottom outside of the test sleeve, the lower fixture connects to the bottom of the bolt shank of the bolt to be tested, thereby enabling the testing of the tensile strength of the short bolt. Attached Figure Description
[0032] Figure 1 This is a cross-sectional schematic diagram of the upper fixture used for testing the tensile strength of existing bolts.
[0033] Figure 2 This is a schematic diagram of the overall structure of an embodiment of this application.
[0034] Figure 3 This is a cross-sectional schematic diagram of the upper clamp used for testing the tensile strength of short bolts in an embodiment of this application.
[0035] Figure 4 yes Figure 3 A magnified view of a portion of point A in the middle.
[0036] Figure 5 This is a cross-sectional schematic diagram of the lower clamp in an embodiment of this application.
[0037] Explanation of reference numerals in the attached drawings: 1. Upper chuck; 11. Clamping seat; 12. Mounting stud; 13. Arrangement chamber; 14. Arrangement through hole; 15. Limiting surface; 2. Snap-fit seat; 3. Upper clamp for testing the tensile strength of short bolts; 31. Test sleeve; 311. Arrangement screw hole; 312. Smooth section; 313. Threaded section; 314. Arrangement tapered hole; 315. Limiting ring surface; 32. Snap-fit ring; 321. Snap-fit through hole; 33. Connector; 34. Mounting post; 341. Limiting groove; 35. Upper stud; 351. First insertion hole; 352. Snap-fit ring groove; 36. Rotating shaft 361. Insertion end; 3611. Plunger hole; 362. Holding end; 37. Anti-slip sleeve; 38. Ball-head spring plunger; 381. Plunger ball; 39. Clamping assembly; 391. First baffle; 3911. First limiting post; 3912. Arc-shaped surface; 392. Second baffle; 3921. Second limiting post; 3922. Annular protrusion; 393. Clamping spring; 4. Lower clamp; 41. Clamp seat; 411. Arrangement groove; 412. Connecting through hole; 413. Abutment surface; 42. Connector; 421. Threaded connecting hole; 43. Connecting bolt. Detailed Implementation
[0038] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.
[0039] This application discloses a fixture assembly for testing the tensile strength of short bolts.
[0040] Reference Figure 2 A fixture assembly for testing the tensile strength of short bolts includes an upper fixture 3 and a lower fixture 4 for testing the tensile strength of short bolts.
[0041] Reference Figure 3 The upper clamp 3 for testing the tensile strength of short bolts includes a test sleeve 31, a snap ring 32, and a connector 33.
[0042] Reference Figure 3 The test sleeve 31 has a screw hole 311 on its top surface for accommodating the snap ring 32 and the bolt to be tested. The screw hole 311 is cylindrical and includes a smooth section 312 and a threaded section 313 from bottom to top. The test sleeve 31 also has a tapered hole 314 connecting the bottom surface of the screw hole 311 and the bottom surface of the test sleeve 31 for accommodating the snap ring 32. The inner diameter of the tapered hole 314 gradually decreases from top to bottom. The screw hole 311 and the tapered hole 314 are coaxially arranged, and the inner diameter of the top of the tapered hole 314 is smaller than the inner diameter of the screw hole 311. A limiting annular surface 315 is formed at the connection between the screw hole 311 and the tapered hole 314 in the test sleeve 31.
[0043] Reference Figure 3The snap ring 32 has a conical structure, and the angle between the outer conical surface and the large end face of the snap ring 32 is 45° to 65°. In this embodiment, the angle between the outer conical surface and the large end face of the snap ring 32 is 55°.
[0044] Reference Figure 3 The snap-fit ring 32 has a central snap-fit through-hole 321 that extends through both the upper and lower surfaces, allowing the bolt of the bolt to be tested to pass through. After the snap-fit ring 32 is fitted onto the bolt of the bolt to be tested, the snap-fit ring 32 and the bolt are inserted into the screw hole 311 through the upper opening, allowing the bolt's bolt to pass through the snap-fit through-hole 321 and the conical hole 314 and extend to the bottom outer side of the test sleeve 31. The bottom of the bolt head abuts against the top of the snap-fit ring 32, and the conical surface of the snap-fit ring 32 is in contact with the inner conical surface of the conical hole 314.
[0045] Reference Figure 3 The connector 33 includes a mounting post 34 that mates with the threaded section 313 of the screw hole 311, and an upper stud 35 connected to the top of the mounting post 34. To facilitate easier screwing of the mounting post 34 into the threaded section 313 of the screw hole 311, the upper stud 35 has a radially penetrating first insertion hole 351, and a rotating shaft 36 is detachably mounted at the first insertion hole 351. The rotating shaft 36 has a cylindrical structure, with an insertion end 361 for mates with the first insertion hole 351 and a holding end 362 away from the insertion end 361. The outer side of the holding end 362 is fitted with an anti-slip sleeve 37, the outer surface of which is provided with anti-slip texture.
[0046] Reference Figure 3 and Figure 4 To prevent the rotating rod from disengaging from the first insertion hole 351 when the operator rotates the upper stud 35 via the rotating shaft 36, the rotating shaft 36 has a plunger hole 3611 on the outer wall of the insertion end 361, and a ball spring plunger 38 is installed in the plunger hole 3611. The inner diameter of the plunger hole 3611 is equal to the outer diameter of the ball spring plunger 38. The upper stud 35 has a retaining ring groove 352 circumferentially provided on the inner wall of the first insertion hole 351 for engaging the plunger balls 381 of the ball spring plunger 38.
[0047] Reference Figure 3 In order to ensure that the conical surface of the snap ring 32 can fit against the inner conical surface of the conical hole 314 and that the bolt to be tested can remain vertical, a clamping assembly 39 is also provided between the mounting post 34 and the snap ring 32. The clamping assembly 39 includes a first baffle 391 abutting against the bottom surface of the mounting post 34, a second baffle 392 abutting against the top surface of the snap ring 32, and a clamping spring 393 arranged between the first baffle 391 and the second baffle 392.
[0048] Reference Figure 3 The bottom of the first baffle 391 has a first limiting post 3911 for engaging with the top of the compression spring 393, and the top of the first baffle 391 has an arc-shaped surface 3912. The bottom surface of the mounting post 34 has a limiting groove 341 for abutting against the arc-shaped surface 3912 of the first baffle 391, thus minimizing friction between the mounting post 34 and the first baffle 391 during rotation.
[0049] Reference Figure 3 The second baffle 392 has a second limiting post 3921 at its top for engaging with the bottom of the compression spring 393. The bottom surface of the second baffle 392 has an annular protrusion 3922 circumferentially arranged. When the mounting post 34 is screwed into the arrangement screw hole 311, it drives the first baffle 391 downwards. Under the action of the compression spring 393, the inner area of the bottom surface of the annular protrusion 3922 presses against the engaging ring 32, and the outer area of the bottom surface of the annular protrusion 3922 presses against the limiting ring surface 315, ensuring that the top surface of the engaging ring 32 remains flush with the limiting ring surface 315. The outer diameter of the annular protrusion 3922 is smaller than the inner diameter of the smooth section 312 of the arrangement screw hole 311, preventing interference between the annular protrusion 3922 and the smooth section 312 when moving within the arrangement screw hole 311.
[0050] Reference Figure 2 and Figure 5 The lower clamp 4 includes a clamp base 41, a connector 42 arranged in the clamp base 41 for the nut of the bolt to be tested to abut against, and a connecting bolt 43 connected to the bottom of the clamp base 41.
[0051] Reference Figure 3 and Figure 5 The fixture base 41 has an arrangement groove 411 on its side wall for arranging the connector 42 and the screw of the bolt to be tested. The fixture base 41 also has a connecting through hole 412 connecting the top surface of the arrangement groove 411 and the top surface of the fixture base 41 for the bolt to be tested to pass through. At the junction of the arrangement groove 411 and the connecting through hole 412, the fixture base 41 forms an abutment surface 413 for the connector 42 to abut against. The connector 42 has a threaded connection hole 421 along its central axis for arranging the screw of the bolt to be tested. When the screw of the bolt to be tested extends from the bottom of the test sleeve 31 to the outside, the screw of the bolt to be tested passes through the threaded connection hole 421 and connects with the nut of the bolt to be tested, such that the top of the nut of the bolt to be tested abuts against the bottom of the connector 42.
[0052] Combination Figures 1 to 5The implementation principle of a fixture assembly for testing the tensile strength of a short bolt in this application embodiment is as follows: when the bolt to be tested passes through the snap-fit through hole 321 of the snap-fit ring 32 and the bolt to be tested and the snap-fit ring 32 are arranged in the arrangement screw hole 311 of the test sleeve 31, the conical surface of the snap-fit ring 32 fits against the inner surface of the arrangement conical hole 314, so that the bolt of the bolt to be tested extends to the bottom outer side of the test sleeve 31; the connector 42 of the lower fixture 4 is connected to the bottom of the bolt of the bolt to be tested and the nut of the bolt to be tested is connected to the bolt of the bolt to be tested, so that the top surface of the nut of the bolt to be tested abuts against the bottom surface of the connector 42; thereby enabling the tensile strength of the short bolt to be tested.
[0053] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. An upper clamp for testing the tensile strength of short bolts, characterized in that, The test sleeve (31), the snap ring (32), and the connector (33) are included. The snap ring (32) is conical and has a snap-fit through hole (321) that passes through the upper and lower surfaces for the threaded rod of the bolt to be tested to pass through. The connector (33) includes a mounting post (34) and an upper stud (35) connected to the top of the mounting post (34). The top surface of the test sleeve (31) is provided with a layout screw hole (311) for the threaded installation of the mounting post (34). The test sleeve (31) is also provided with a layout conical hole (314) that connects the bottom surface of the layout screw hole (311) and the bottom surface of the test sleeve (31) and is used for the arrangement of the snap ring (32). The layout screw hole (311) includes a smooth section (312) and a threaded section (313) from bottom to top.
2. The upper clamp for testing the tensile strength of a short bolt according to claim 1, characterized in that, A clamping assembly (39) is provided between the mounting post (34) and the snap ring (32); the clamping assembly (39) includes a first baffle (391) abutting against the mounting post (34), a second baffle (392) abutting against the top surface of the snap ring (32), and a clamping spring (393) arranged between the first baffle (391) and the second baffle (392); the bottom surface of the second baffle (392) is provided with an annular protrusion (3922) for clamping the snap ring (32) in the circumferential direction.
3. The upper clamp for testing the tensile strength of a short bolt according to claim 2, characterized in that, The maximum diameter of the arrangement conical hole (314) is smaller than the diameter of the arrangement screw hole (311). The test sleeve (31) forms a limiting annular surface (315) at the connection between the arrangement screw hole (311) and the arrangement conical hole (314). The inner area of the bottom surface of the annular protrusion (3922) is pressed against the snap ring (32), and the outer area of the bottom surface of the annular protrusion (3922) is pressed against the limiting annular surface (315).
4. The upper clamp for testing the tensile strength of a short bolt according to claim 3, characterized in that, The outer diameter of the annular protrusion (3922) is adapted to the inner diameter of the smooth section (312) of the screw hole (311).
5. The upper clamp for testing the tensile strength of a short bolt according to claim 2, characterized in that, The bottom surface of the mounting post (34) is provided with a limiting groove (341), and the top surface of the first baffle (391) is an arc-shaped surface (3912) that abuts against the bottom surface of the limiting groove (341).
6. The upper clamp for testing the tensile strength of a short bolt according to claim 1, characterized in that, The upper stud (35) is provided with a radially and through first insertion hole (351) and a rotating shaft (36) is detachably installed at the first insertion hole (351); the rotating shaft (36) has a plug-in end (361) for engaging with the first insertion hole (351) and a holding end (362) away from the plug-in end (361).
7. The upper clamp for testing the tensile strength of a short bolt according to claim 6, characterized in that, The rotating shaft (36) has a plunger hole (3611) on the outer side wall of the insertion end (361) and a ball spring plunger (38) is installed in the plunger hole (3611); the upper stud (35) has a snap-fit ring groove (352) on the inner wall of the first insertion hole (351) for snapping the plunger ball (381) of the ball spring plunger (38).
8. The upper clamp for testing the tensile strength of a short bolt according to claim 6, characterized in that, The rotating shaft (36) is fitted with an anti-slip sleeve (37) on the gripping end (362), and the outer surface of the anti-slip sleeve (37) is provided with anti-slip texture.
9. The upper clamp for testing the tensile strength of a short bolt according to claim 1, characterized in that, The angle between the outer conical surface of the snap ring (32) and the large end face of the snap ring (32) is 30° to 50°.
10. A fixture assembly for testing the tensile strength of short bolts, characterized in that, It includes a lower clamp (4) and an upper clamp (3) for testing the tensile strength of short bolts as described in any one of claims 1 to 9.