Steering gear and idler structure

Abstract

The utility model discloses a steering gear and idler structure, including inside adjusting block, bearing, outside adjusting block and adjusting pin, the bearing inner ring is with inside adjusting block outer wall wall interference fit, and bearing outer ring is with outside adjusting block inner wall wall interference fit, inside adjusting block and outside adjusting block coaxial arrangement, and inside adjusting block is equipped with the positioning pin of hollow, the axis of positioning pin inside adjusting block's central axis eccentricity sets up, positioning pin protrudes from inside adjusting block end face and is used for with steering casing cooperation, adjusting pin one end is located inside adjusting block outside, and adjusting pin other end passes through positioning pin and is used for inserting steering casing. Eliminate the complex stress state of adjusting pin in traditional structure and bear radial shearing force and axial tension simultaneously, avoid screw plastic deformation or thread damage. When tightening adjusting pin, because there is no radial force interference, spanner torque can be completely converted into axial pre-tightening force, and it is ensured that idler fixed is reliable.

Description

Technical Field

[0001] This utility model relates to the field of mechanical transmission technology, specifically to a steering gear and idler wheel structure. Background Technology

[0002] In belt- or chain-driven steering systems, the idler pulley is a key component for adjusting the tension of the synchronous belt. Traditional idler pulleys employ an eccentric adjustment structure: rotating the inner ring of the idler pulley with a wrench causes it to rotate eccentrically around the axis of the adjusting screw, thereby pushing the outer ring to compress the belt and generate tension. During this process, the belt's reaction force creates a radial load perpendicular to the axis of the adjusting screw. This radial force is ultimately transmitted to the fixing screw, causing the screw to bear combined stresses, namely axial compressive force and radial shear force. Although tightening the screw with a wrench can temporarily fix the idler pulley, under long-term alternating loads, the screw is prone to plastic deformation or thread loosening due to continuous radial force, leading to idler pulley displacement, belt tension reduction, and affecting transmission stability and lifespan. Existing improvements attempt to increase screw strength or add anti-loosening structures, but they fail to fundamentally eliminate the interference of radial force on the fixing component, and the risk of loosening remains. Therefore, a new idler pulley fixing structure that can effectively distribute radial load is urgently needed. Utility Model Content

[0003] To address the aforementioned technical problems, this utility model proposes a steering gear and idler wheel structure that eliminates the combined stress state of radial shear force and axial tensile force simultaneously on the adjusting pin in the traditional structure, thereby avoiding plastic deformation of the screw or damage to the thread.

[0004] The technical solution adopted by this utility model is as follows: an idler wheel structure includes an inner adjusting block, a bearing, an outer adjusting block, and an adjusting pin. The inner ring of the bearing is interference-fitted with the outer peripheral wall of the inner adjusting block, and the outer ring of the bearing is interference-fitted with the inner peripheral wall of the outer adjusting block. The inner adjusting block and the outer adjusting block are coaxially arranged, and the inner adjusting block is provided with a hollow positioning pin. The axis of the positioning pin is eccentrically arranged with respect to the central axis of the inner adjusting block. The positioning pin protrudes from the end face of the inner adjusting block and is used to cooperate with the steering housing. One end of the adjusting pin is located outside the inner adjusting block, and the other end of the adjusting pin passes through the positioning pin and is used to insert into the steering housing.

[0005] Optionally, the inner adjusting block is provided with an eccentric hole through which the positioning pin passes, and the outer wall of the positioning pin is press-fitted with the eccentric hole.

[0006] Optionally, the end face of the inner adjusting block facing the housing is a rough surface.

[0007] Optionally, the adjusting pin is a screw.

[0008] Optionally, the rough surface is formed by laser etching.

[0009] This utility model also discloses a steering gear, including a first pulley, a second pulley, a timing belt, a steering housing, and the idler gear structure described above. The timing belt is wound around the outer peripheral walls of the first pulley and the second pulley. The steering housing is provided with a positioning hole, and the positioning pin protrudes from the inner adjusting block portion and is inserted into the positioning hole.

[0010] Optionally, the steering housing is provided with a boss, the end face of the boss abuts against the end face of the inner adjusting block, the boss is provided with the positioning hole, the length of the outer adjusting block is greater than the length of the inner adjusting block, and the outer adjusting block is sleeved on the outer peripheral wall of the boss.

[0011] Optionally, the boss is provided with an adjustment hole that cooperates with the adjustment pin. The adjustment hole communicates with the positioning hole, and the diameter of the positioning hole is larger than the diameter of the adjustment hole.

[0012] The beneficial effects of this invention are as follows: Compared to the existing structure where the adjusting pin directly passes through the inner adjusting block and connects to the steering housing, this embodiment integrates an eccentric positioning pin and the adjusting pin in the inner adjusting block to form a dual load path. The reverse force (radial load) generated when the idler pulley squeezes the belt is decomposed into two transmission paths. The tangential component is borne by the positioning pin and the positioning hole of the steering housing, forming a force couple to resist the rotational torque. The axial component is balanced by the axial clamping force of the adjusting pin, eliminating the combined stress state of radial shear force and axial tensile force simultaneously borne by the adjusting pin in the traditional structure, and avoiding plastic deformation of the screw or damage to the threads. When tightening the adjusting pin, since there is no radial force interference, the wrench torque can be completely converted into axial preload, ensuring reliable fixing of the idler pulley. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the idler wheel structure proposed in an embodiment of the present invention;

[0014] Figure 2 This is a cross-sectional view of the idler wheel structure proposed in an embodiment of this utility model;

[0015] Figure 3 This is a cross-sectional view of the internal adjustment block proposed in an embodiment of the present utility model;

[0016] Figure 4 This is a schematic diagram of the steering housing of the steering gear proposed in an embodiment of the present utility model;

[0017] Figure 5 This is a schematic diagram of the steering system proposed in an embodiment of the present utility model.

[0018] The markings in the attached figures are as follows: 1. Inner adjusting block; 101. Eccentric hole; 102. Rough surface; 2. Bearing; 3. Outer adjusting block; 4. Locating pin; 5. Adjusting pin; 6. Steering housing; 601. Locating hole; 602. Boss; 7. First pulley; 8. Second pulley; 9. Synchronous belt. Detailed Implementation

[0019] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.

[0020] like Figures 1 to 5 As shown, this embodiment discloses a steering gear and idler wheel structure, including an inner adjusting block 1, a bearing 2, an outer adjusting block 3, and an adjusting pin 5. The inner ring of the bearing 2 is interference-fitted with the outer peripheral wall of the inner adjusting block 1, and the outer ring of the bearing 2 is interference-fitted with the inner peripheral wall of the outer adjusting block 3. The inner adjusting block 1 and the outer adjusting block 3 are coaxially arranged, and the inner adjusting block 1 is provided with a hollow positioning pin 4. The axis of the positioning pin 4 is eccentrically arranged with respect to the central axis of the inner adjusting block 1. The positioning pin 4 protrudes from the end face of the inner adjusting block 1 and is used to cooperate with the steering housing 6. One end of the adjusting pin 5 is located outside the inner adjusting block 1, and the other end of the adjusting pin 5 passes through the positioning pin 4 and is used to insert into the steering housing 6. Compared to the existing technology where the adjusting pin 5 directly passes through the inner adjusting block 1 and connects to the steering housing 6, this embodiment integrates an eccentric positioning pin 4 and the adjusting pin 5 in the inner adjusting block 1 to form a dual load path. The reverse force (radial load) generated when the idler pulley squeezes the belt is decomposed into two transmission paths. The tangential component is borne by the positioning pin 4 and the positioning hole 601 of the steering housing 6, forming a couple to resist the rotational torque. The axial component is balanced by the axial clamping force of the adjusting pin 5, eliminating the combined stress state of radial shear force and axial tensile force simultaneously borne by the adjusting pin 5 in the traditional structure, and avoiding plastic deformation of the screw or damage to the threads. When tightening the adjusting pin 5, since there is no radial force interference, the wrench torque can be completely converted into axial preload, ensuring reliable fixing of the idler pulley.

[0021] like Figure 3 As shown, in this embodiment, the inner adjusting block 1 is provided with an eccentric hole 101 through which the positioning pin 4 passes, and the outer wall of the positioning pin 4 is press-fitted with the eccentric hole 101. This ensures that the positioning pin 4 is securely installed and accurately transmits tangential force, thereby improving structural rigidity.

[0022] like Figure 3 As shown, in this embodiment, the end face of the inner adjusting block 1 facing the housing is a rough surface 102. This increases the coefficient of friction between the inner adjusting block 1 and the steering housing 6, suppressing the circumferential displacement of the idler wheel. The rough surface 102 is formed by laser etching. Laser etching precisely controls the surface roughness, improving friction performance without damaging the strength of the substrate. The rough surface 102 can also be achieved through other processes such as sandblasting.

[0023] like Figure 2 As shown, the adjusting pin 5 in this embodiment is a screw. Tightening with the thread provides a controllable axial clamping force, facilitating assembly and disassembly.

[0024] like Figure 4 and 5As shown, this embodiment discloses a steering gear, including a first pulley 7, a second pulley 8, a synchronous belt 9, a steering housing 6, and the idler structure described above. The synchronous belt 9 is wound around the outer peripheral walls of the first pulley 7 and the second pulley 8. The steering housing 6 is provided with a positioning hole 601, and the positioning pin 4 protrudes from the inner adjusting block 1 and is inserted into the positioning hole 601. Through the double-pin design of the positioning pin 4 and the adjusting pin 5 of the idler structure, the radial interference of the synchronous belt 9 tension on the adjusting pin 5 is eliminated, improving the stability of the belt drive.

[0025] like Figure 4 As shown, in this embodiment, the steering housing 6 is provided with a boss 602. The end face of the boss 602 abuts against the end face of the inner adjusting block 1. The boss 602 is provided with the positioning hole 601. The length of the outer adjusting block 3 is greater than the length of the inner adjusting block 1, and the outer adjusting block 3 is sleeved on the outer peripheral wall of the boss 602. Radial positioning is achieved by using the boss 602, and the outer adjusting block 3 covers the boss 602 to enhance the anti-overturning capability. The boss 602 can be integrally formed with the steering housing 6.

[0026] like Figure 4 As shown, in this embodiment, the boss 602 is provided with an adjustment hole that mates with the adjustment pin 5. The adjustment hole communicates with the positioning hole 601, and the diameter of the positioning hole 601 is larger than the diameter of the adjustment hole. The larger diameter of the positioning hole 601 accommodates the eccentric installation tolerance of the positioning pin 4, while the smaller diameter of the adjustment hole precisely guides the adjustment pin 5, ensuring assembly accuracy.

[0027] It is understood that the specific embodiments described above are merely for explaining the relevant utility model and not for limiting the utility model. It should also be noted that, for ease of description, only the parts related to the utility model are shown in the accompanying drawings. Multiple technical solutions in the same embodiment, as well as multiple technical solutions in different embodiments, can be arranged and combined to form new technical solutions that do not contradict or conflict with each other. All equivalent structural transformations made based on the content of this utility model specification and drawings, directly or indirectly applied to other related technical fields, are similarly included within the protection scope of this utility model.

Claims

1. A idler structure, characterized by, Includes inner adjusting block, bearing, outer adjusting block, and adjusting pin. The inner ring of the bearing is interference-fitted with the outer peripheral wall of the inner adjusting block, and the outer ring of the bearing is interference-fitted with the inner peripheral wall of the outer adjusting block. The inner adjusting block and the outer adjusting block are coaxially arranged, and the inner adjusting block is provided with a hollow positioning pin. The axis of the positioning pin is eccentrically arranged with respect to the central axis of the inner adjusting block. The positioning pin protrudes from the end face of the inner adjusting block and is used to cooperate with the steering housing. One end of the adjusting pin is located outside the inner adjusting block, and the other end of the adjusting pin passes through the positioning pin and is used to insert into the steering housing.

2. The idler structure of claim 1, wherein The inner adjusting block is provided with an eccentric hole through which the positioning pin passes, and the outer wall of the positioning pin is press-fitted with the eccentric hole.

3. The idler structure of claim 1, wherein The end face of the inner adjusting block facing the housing is a rough surface.

4. The idler structure of claim 1, wherein The adjusting pin is a screw.

5. A diverter characterized by, The device includes a first pulley, a second pulley, a timing belt, a steering housing, and an idler structure as described in any one of claims 1 to 4. The timing belt is wound around the outer peripheral walls of the first pulley and the second pulley. The steering housing is provided with a positioning hole, and the positioning pin protrudes from the inner adjusting block portion and is inserted into the positioning hole.

6. The diverter of claim 5, wherein, The steering housing is provided with a boss, the end face of which abuts against the end face of the inner adjusting block. The boss is provided with the positioning hole. The length of the outer adjusting block is greater than the length of the inner adjusting block. The outer adjusting block is sleeved on the outer peripheral wall of the boss.

7. The steering system according to claim 6, characterized in that, The boss is provided with an adjustment hole that cooperates with the adjustment pin. The adjustment hole is connected to the positioning hole, and the diameter of the positioning hole is larger than the diameter of the adjustment hole.

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