Test tool for strength test of worm gear and worm of automobile steering column

Abstract

A testing tool for testing the strength of a worm gear and a worm of an automobile steering column comprises a shell used for installing a worm gear assembly and a worm assembly which are matched with each other, a limiting and locking assembly for the worm assembly is arranged at an outer hole opening of a worm assembly installing part of the shell, and the limiting and locking assembly comprises a limiting rod and a fixing block. The fixing block is detachably fixed to the outer hole opening, the inner end of the limiting rod and the end of the worm assembly are correspondingly provided with circumferential limiting structures capable of being embedded in the axial direction, the limiting rod is inserted into the through hole of the fixing block in a penetrating mode, and an anti-rotation structure is arranged between the limiting rod and the through hole of the fixing block. And an axial positioning adjusting assembly for axially positioning the limiting rod is arranged on the fixing block or the limiting rod. The test tool can test worm gears and worms of various specifications, and has the advantages of being good in universality, convenient to operate, low in cost and the like.

Description

Technical Field

[0001] The invention relates to a test fixture for testing the strength of a worm gear of an automobile steering column, and belongs to the technical field of worm gear strength testing devices. Background Art

[0002] When a car is driving, it needs to frequently change its driving direction according to the driver's will, which is called car steering. In addition to affecting the driver's driving experience, car steering is also related to the driver's life safety. A qualified car steering product must pass various tests and verifications before it can enter the market. Worm gears and worms are important components in the steering column. In the design and development process of the steering column, the design of worm gears and worms is particularly important. Among them, the strength of worm gears and worms involves the safety of the product, which is the top priority in the design and development process. In addition to the early design, subsequent test verification can better guarantee the quality of the product. During the test verification, different test fixtures need to be designed according to different product sizes, which requires a lot of time, money and tooling management costs. Summary of the invention

[0003] The purpose of the present invention is to address the above-mentioned technical defects of the existing worm gear strength testing technology and to provide a test fixture for a worm gear strength test on an automobile steering column. The test fixture can be used to test worm gears of various specifications and has the advantages of good versatility, convenient operation and low cost.

[0004] The above technical objectives of the present invention are achieved through the following technical solutions:

[0005] A test fixture for a worm gear strength test of an automobile steering column comprises a housing for mounting a turbine assembly and a worm assembly that cooperate with each other, an outer opening of a worm assembly placement portion of the housing is provided with a limit locking assembly for the worm assembly, the limit locking assembly comprises a limit rod and a fixed block, the fixed block is detachably fixed to the outer opening, an inner end of the limit rod and an end of the worm assembly are provided with a circumferential limit structure that can axially engage with each other, the limit rod is inserted into a through hole of the fixed block, an anti-rotation structure is provided between the limit rod and the through hole of the fixed block, and an axial positioning adjustment assembly for axially positioning the limit rod is provided on the fixed block or the limit rod.

[0006] By adopting the above technical solution, a test fixture for the strength test of the worm gear of an automobile steering column is provided, which can realize the test of worm gears of various specifications and has the advantages of good versatility, convenient operation, low cost, etc.

[0007] The present invention is further configured as follows: the through hole of the fixing block is a strip-shaped hole, and the side wall of the rod body of the limiting rod is provided with a limiting plane matching the long hole edge of the strip-shaped hole.

[0008] By adopting the above technical solution, the anti-rotation structure between the limiting rod and the through hole of the fixing block is limited.

[0009] The present invention is further configured as follows: the axial positioning adjustment assembly comprises an inner positioning nut screwed onto a rod body of an inner limiting rod of the fixing block.

[0010] By adopting the above technical solution, the axial positioning adjustment component is limited, and the inner positioning nut spirally mounted on the inner limit rod of the fixed block can be rotated to adjust and position the position of the limit rod and the fixed bar from the inside, which can effectively prevent the limit rod from axially sliding in the through hole of the fixed block during the test.

[0011] The present invention is further configured as follows: an outer positioning nut is provided on the limiting rod outside the fixing block.

[0012] By adopting the above technical solution, an outer positioning nut is provided on the limit rod body outside the fixed block. When in use, the inner positioning nut can be positioned and adjusted first, and then the outer positioning nut can be positioned and adjusted. The outer positioning nut can cooperate with the inner positioning nut to position the limit rod from both sides inside and outside the fixed block, which can further avoid axial runout of the limit rod during the test and can further ensure the accuracy of the test result.

[0013] The present invention is further configured as follows: the inner positioning nut and the outer positioning nut are both screwed onto threads on an arc-shaped curved surface at the same circumferential position as the limiting plane.

[0014] By adopting the above technical scheme, the spiral installation method of the inner and outer positioning nuts on the limit rod is limited. This scheme makes the structure of the limit rod relatively simple. At the same time, it ensures the effective coordination between the limit plane and the strip hole, and avoids the contact between the threaded arc surface next to the limit plane and the strip hole, which has extremely strong practicality.

[0015] The present invention is further configured as follows: the fixed block is an arched structure with a middle portion protruding outward, the through hole is located in the middle portion of the arched structure, a rotating sleeve coaxial with the limiting rod is rotatably arranged on the inner side of the arched structure, the rotating sleeve is sleeved on the outer ring of the inner positioning nut, and mutually engaging axial ridges and axial grooves are arranged between the inner wall of the rotating sleeve and the outer ring side wall of the inner positioning nut, the rotation of the rotating sleeve can drive the inner positioning nut to rotate, and the outer diameter of the rotating sleeve is larger than the lateral dimension of the arched structure.

[0016] By adopting the above technical solution, a fixed block with a middle portion protruding outward is provided. The fixed block cooperates with the design of "rotating sleeve + inner positioning nut". By rotating the rotating sleeve, the axial movement of the inner positioning nut on the limit rod when it is inside the shell can be achieved. This design can more effectively improve the convenience of positioning and adjusting the inner positioning nut.

[0017] The present invention is further configured as follows: an anti-rotation structure that can be axially engaged is provided between the outer end of the rotating sleeve and the inner side of the arch structure, and the anti-rotation structure can be separated and engaged by axially moving the rotating sleeve.

[0018] By adopting the above technical solution, when the rotating sleeve needs to be rotated, the rotating sleeve is moved axially to disengage the anti-rotation structure. When the inner positioning nut is adjusted into place, the rotating sleeve is moved axially to engage the anti-rotation structure, thereby achieving anti-rotation of the inner positioning nut and effectively preventing the inner positioning nut from loosening during use.

[0019] The present invention is further configured as follows: a U-shaped limit piece is arranged between the rotating sleeve and the arch structure, the U-shaped limit piece includes a retaining ring on the limit rod body and limit blocks vertically fixed at both ends of the same side of the retaining ring, the limit blocks are attached to both sides of the middle part of the arch structure, and the inner sides of the two limit blocks are provided with limit grooves corresponding to the outer ring of the outer positioning nut; at this time, an anti-rotation structure that can be axially clamped is arranged between the outer end surface of the rotating sleeve and the retaining ring.

[0020] By adopting the above technical solution, a U-shaped limiter is provided between the rotating sleeve and the arch structure, and an anti-rotation structure that can be axially engaged is provided between the outer end surface of the rotating sleeve and the retaining ring. When in use, after the outer positioning nut is placed in place, the inner positioning nut is tightly attached to the retaining ring of the U-shaped limiter by rotating the rotating sleeve. During this process, the inner positioning nut pushes the U-shaped limiter outward. When the two limit blocks of the U-shaped limiter cooperate with the outer ring of the outer positioning nut, the outer positioning nut can be effectively prevented from loosening. At this time, the rotating sleeve can also be axially moved to axially engage the anti-rotation structure between the rotating sleeve and the retaining ring of the U-shaped limiter, thereby realizing simultaneous positioning of the inner and outer positioning nuts. This solution can further improve the positioning effect and prevent the inner and outer positioning nuts from loosening during use.

[0021] The present invention is further configured as follows: the fixing block is in the shape of a straight bar.

[0022] By adopting the above technical solution, a fixing block with another structure is provided.

[0023] The present invention is further configured as follows: both ends of the fixing block are provided with mounting strip holes parallel to the axis of the fixing block, and the fixing block is fixed to the outer opening of the shell by two bolts passing through the mounting strip holes.

[0024] By adopting the above technical solution, mounting holes parallel to the axis of the fixing block are set at both ends of the fixing block. The design of the mounting holes allows the fixing block to cooperate with shells of more specifications, which can effectively improve the versatility of the fixing block.

[0025] The main beneficial effects of the present invention are:

[0026] 1. The test fixture of the present invention can realize the test of worm gears of various specifications, and has the advantages of good versatility, convenient operation, low cost, etc.

[0027] 2. The test fixture of the present invention is provided with positioning nuts on the rod bodies of the limiting rods on both sides of the fixed block. The combined use of the two positioning nuts can effectively avoid axial runout of the limiting rods during the test, effectively prolong the service life of the fixture and improve the accuracy of the test.

[0028] 3. The present invention also provides a fixing block with a protruding middle portion, which cooperates with the design of "rotating sleeve + inner positioning nut". By rotating the rotating sleeve, the axial movement of the inner positioning nut on the limit rod when it is inside the shell can be achieved. This design can more effectively improve the convenience of positioning and adjusting the inner positioning nut.

[0029] 4. The present invention provides an anti-rotation structure between the outer end of the rotating sleeve and the inner side of the arch structure. When the rotating sleeve needs to be rotated, the rotating sleeve is moved axially to disengage the anti-rotation structure. When the inner positioning nut is adjusted into place, the rotating sleeve is moved axially to engage the anti-rotation structure, thereby preventing the inner positioning nut from loosening during use.

[0030] 5. The present invention sets a U-shaped limiter between the rotating sleeve and the arch structure, and in this case, an anti-rotation structure that can be axially engaged is set between the outer end surface of the rotating sleeve and the retaining ring. During use, after the outer positioning nut is put in place, the inner positioning nut and the retaining ring of the U-shaped limiter are tightly attached by rotating the rotating sleeve. During this process, the inner positioning nut will push the U-shaped limiter outward. When the two limit blocks of the U-shaped limiter are matched with the outer ring of the outer positioning nut, the outer positioning nut can be effectively prevented from loosening. At this time, the rotating sleeve can also be moved axially to axially engage the anti-rotation structure between the rotating sleeve and the retaining ring of the U-shaped limiter, so as to realize simultaneous positioning of the inner and outer positioning nuts. This solution can further improve the positioning effect and prevent the inner and outer positioning nuts from loosening during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 is a schematic structural diagram of Embodiment 1 of the present invention;

[0033] Figure 2 is an exploded view of the first embodiment of the present invention;

[0034] Figure 3 It is a schematic diagram of the structure of the second and third embodiments of the present invention;

[0035] Figure 4 It is an exploded view of the second and third embodiments of the present invention.

[0036] In the figure, 1, housing; 11, worm assembly placement part; 111, outer orifice; 2, worm assembly; 3, turbine assembly; 41, inner positioning nut; 42, outer positioning nut; 23, limit rod; 51, circumferential limit structure; 52, limit plane; 53, arc surface; 61, straight strip block; 62, arch structure; 7, bolt; 8, rotating sleeve; 91, retaining ring; 92, limit block. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Embodiment 1:

[0039] like Figure 1 to Figure 2 As shown, a test fixture for a strength test of a worm gear of an automobile steering column includes a housing 1 for mounting a turbine assembly 3 and a worm assembly 2 that cooperate with each other, an outer opening 111 of the worm assembly placement portion 11 of the housing 1 is provided with a limit locking assembly for the worm assembly 2, and the limit locking assembly includes a limit rod 5 and a fixed block, the fixed block is detachably fixed to the outer opening 111, and the inner end of the limit rod 5 and the end of the worm assembly 2 are correspondingly provided with a circumferential limit structure 51 that can be axially interlocked with each other, and the circumferential limit structure 51 is a four-claw clamping block. The limit rod 5 is inserted into the through hole of the fixed block, and an anti-rotation structure is provided between the limit rod 5 and the through hole of the fixed block, and an axial positioning adjustment assembly for axially positioning the limit rod 5 is provided on the fixed block or the limit rod 5.

[0040] The fixing block is a straight strip block 61, the through hole of the fixing block is a strip hole, and the side wall of the rod body of the limiting rod 5 is provided with a limiting plane 52 matching the long hole of the strip hole. Both ends of the fixing block are provided with mounting strip holes parallel to the axis of the fixing block, and the fixing block is fixed to the outer opening 111 of the housing 1 by two bolts 7 passing through the mounting strip holes.

[0041] The axial positioning adjustment assembly includes an inner positioning nut 41 screwed on the rod body of the inner limiting rod 5 of the fixed block, and an outer positioning nut 42 is provided on the limiting rod 5 outside the fixed block. The inner positioning nut 41 and the outer positioning nut 42 are both screwed on the threads of the arc surface 53 at the same circumferential position as the limiting plane 52.

[0042] How it works:

[0043] First, install the turbine assembly 3 and the worm assembly 2 into the housing 1, and then insert the limit rod 5 from the outer hole 111 to make it axially fit with the circumferential limit structure at the end of the worm assembly 2 to determine the position of the inner positioning nut 41. Then, install the fixing block on the outer hole 111, and then rotate the outer ear positioning nut 42 to achieve the positioning of the limit rod 5.

[0044] Embodiment 2:

[0045] like Figure 3 and Figure 4 As shown, the difference between the second embodiment and the first embodiment is that the fixed block is an arched structure 62 with a protruding middle portion, the through hole is located in the middle portion of the arched structure 62, a rotating sleeve 8 coaxial with the limiting rod 5 is rotatably arranged inside the arched structure 62, the rotating sleeve 8 is sleeved on the outer ring of the inner positioning nut 41, and mutually engaged axial convex ridges and axial grooves are arranged between the inner wall of the rotating sleeve 8 and the outer ring side wall of the inner positioning nut 41, and the outer diameter of the rotating sleeve 8 is larger than the transverse dimension of the arched structure 62. An anti-rotation structure that can be axially engaged is arranged between the outer end surface of the rotating sleeve 8 and the inner side of the arched structure 62, and the anti-rotation structure can be separated and engaged by axially moving the rotating sleeve 8.

[0046] How it works:

[0047] First, install the turbine assembly 3 and the worm assembly 2 into the housing 1, and then insert the limit rod 5 from the outer hole 111. At the same time, the fixed block is sleeved on the limit rod 5 and fixed on the outer hole 111. At this time, the fixed block is in a fixed state. After axially moving the limit rod 5 to cooperate with the grip assembly 2, axially move the rotating sleeve 8 to make the rotating sleeve 8 in a rotatable state, and then rotate the rotating sleeve 8 to achieve the close contact between the inner positioning nut 41 and the inner side of the fixed block. Then axially move the rotating sleeve 8 to make the rotating sleeve 8 in a non-rotatable state to prevent the inner positioning nut 41 from loosening during the test. Finally, rotate the outer ear positioning nut 42 to limit the limit rod 5 from the outside.

[0048] From the technical effect point of view, Example 2 has two obvious advantages over Example 1: First, the operation of the inner positioning nut 41 in Example 2 is more convenient, the axial adjustment distance is longer, and the range of the bar hole is larger; Second, Example 2 has an anti-rotation limit on the inner positioning nut 41, and the inner positioning nut 41 is less likely to loosen during the test.

[0049] Embodiment three:

[0050] like Figure 3 and Figure 4 As shown, the difference between Example 3 and Example 2 is that a U-shaped limit member is arranged between the rotating sleeve 8 and the arch structure 62, and the U-shaped limit member includes a retaining ring 91 on the rod body of the limiting rod 5 and limit blocks 92 vertically fixed at the two ends of the same side of the retaining ring 91, and the limit blocks 92 are attached to both sides of the middle part of the arch structure 61, and the inner sides of the two limit blocks 92 are provided with limit grooves corresponding to the outer ring of the outer positioning nut 42; at this time, an anti-rotation structure that can be axially clamped is arranged between the outer end surface of the rotating sleeve 8 and the retaining ring 91.

[0051] How it works:

[0052] When adjusting the tightness of the limit rod 5, first adjust the outer positioning nut 42 into place, and then adjust the inner positioning nut 41 into place by rotating the rotating sleeve 8. After the inner adjusting nut 41 is adjusted into place, it will push the limit block 92 of the U-shaped limit member to prevent the outer positioning nut 42 from rotating. Finally, the rotating sleeve 8 is moved axially to axially engage the rotating sleeve 8 with the retaining ring 91 of the U-shaped limit member, and both the inner and outer positioning nuts are prevented from rotating, thereby improving the anti-loosening capability.

Claims

1. A test fixture for the strength test of a worm gear of an automobile steering column, characterized in that: The invention comprises a housing (1) for mounting a turbine assembly (3) and a worm assembly (2) which cooperate with each other, an outer opening (111) of a worm assembly placement portion (11) of the housing (1) being provided with a limit locking assembly for the worm assembly (2), the limit locking assembly comprising a limit rod (5) and a fixed block, the fixed block being detachably fixed to the outer opening (111), the inner end of the limit rod (5) and the end of the worm assembly (2) being provided with a circumferential limit structure (51) which can be axially engaged with each other, the limit rod (5) being inserted into a through hole of the fixed block, an anti-rotation structure being provided between the limit rod (5) and the through hole of the fixed block, and an axial positioning adjustment assembly for axially positioning the limit rod (5) being provided on the fixed block or on the limit rod (5).

2. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 1, characterized in that: The through hole of the fixing block is a strip-shaped hole, and the side wall of the rod body of the limiting rod (5) is provided with a limiting plane (52) matching the long hole edge of the strip-shaped hole.

3. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 2, characterized in that: The axial positioning adjustment assembly comprises an inner positioning nut (41) screwedly mounted on the rod body of the inner limiting rod (5) of the fixing block.

4. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 3, characterized in that: An outer positioning nut (42) is arranged on the limiting rod (5) outside the fixing block.

5. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 4, characterized in that: The inner positioning nut (41) and the outer positioning nut (42) are both screwed onto threads on the surface of an arc-shaped curved surface (53) at the same circumferential position as the limiting plane (52).

6. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 3, characterized in that: The fixing block is an arched structure (62) with a middle portion protruding outward, and the through hole is located in the middle portion of the arched structure (62). A rotating sleeve (8) coaxial with the limiting rod (5) is rotatably arranged on the inner side of the arched structure (62), and the rotating sleeve (8) is sleeved on the outer ring of the inner positioning nut (41). Axial ridges and axial grooves that fit in with each other are arranged between the inner wall of the rotating sleeve (8) and the outer ring side wall of the inner positioning nut (41). The rotation of the rotating sleeve (8) can drive the inner positioning nut (41) to rotate, and the outer diameter of the rotating sleeve (8) is larger than the transverse dimension of the arched structure (62).

7. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 6, characterized in that: An anti-rotation structure that can be axially engaged is provided between the outer end surface of the rotating sleeve (8) and the inner side of the arch structure (62); the anti-rotation structure can be separated and engaged by axially moving the rotating sleeve (8).

8. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 6, characterized in that: A U-shaped limit piece is arranged between the rotating sleeve (8) and the arch structure (62), and the U-shaped limit piece includes a retaining ring (91) on the rod body of the limit rod (5) and limit blocks (92) respectively fixed vertically at the two ends of the same side of the retaining ring (91), and the limit blocks (92) are attached to the two sides of the middle of the arch structure (61), and the inner sides of the two limit blocks (92) are provided with limit grooves corresponding to the outer ring of the outer positioning nut (42); at this time, an anti-rotation structure that can be axially clamped is arranged between the outer end surface of the rotating sleeve (8) and the retaining ring (91).

9. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 1, characterized in that: The fixing block is a straight strip block (61).

10. The test fixture for the strength test of the worm gear of the automobile steering column according to claim 1, characterized in that: Both ends of the fixing block are provided with mounting strip holes parallel to the axis of the fixing block, and the fixing block is fixed to the outer opening (111) of the housing (1) by two bolts (7) passing through the mounting strip holes.

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