Rack and pinion steering gear load simulation tooling

Abstract

This utility model discloses a load simulation fixture for a rack and pinion steering gear. In use, the rack and pinion steering gear is placed on a test bench, and the mounting holes on the steering gear housing are positioned on the positioning pins. The positioning assembly consists of four sets, with the four positioning pins fixing the steering gear housing around its perimeter. Then, the steering gear tie rod is placed into the contour groove. By manually rotating the steering wheel, the tie rod moves horizontally to the left or right. The contour block drives the support plate to move synchronously, and the support plate drives the load tie rod to move. The load block applies a load to the tie rod through friction, and the load block applies friction to the load rod to simulate tire ground resistance. The tension sensor monitors the load force in real time, achieving accurate simulation of the steering gear load condition under unassisted conditions.

Description

Technical Field

[0001] This utility model relates to the technical field of steering gear testing equipment, specifically to a load simulation fixture for rack and pinion steering gears. Background Technology

[0002] In steering gear noise testing, certain abnormal noise issues may not be detected under no-load conditions. Therefore, it is necessary to test by simulating the frictional resistance (load) between the tire and the ground. However, conventional load application methods are servo motor loading or hydraulic loading, both of which have significant drawbacks:

[0003] Servo motor loading: The servo motor itself may produce abnormal noises during operation, and its load unit may resonate with the steering system, which seriously interferes with the identification and judgment of the actual abnormal noises of the steering gear;

[0004] Hydraulic loading: The valves in the hydraulic system have a slow response time. When performing rapid steering operations, i.e., rapidly turning the steering wheel left or right, the hydraulic valves cannot adjust the pressure in time, causing the load on both sides to fail momentarily or fail to follow accurately, thus failing to effectively simulate load changes under real working conditions.

[0005] Therefore, there is an urgent need to develop a new form of load loading to overcome the above problems. Utility Model Content

[0006] To address the aforementioned technical problems, this utility model proposes a rack and pinion steering gear load simulation fixture. The load block applies frictional force to the load rod to simulate tire ground resistance, and a tension sensor monitors the load force in real time, thereby achieving accurate simulation of the steering gear load conditions under unassisted conditions.

[0007] The technical solution adopted by this utility model is as follows: A rack and pinion steering gear load simulation fixture includes a frame, a positioning component, a support component, and a load component. The positioning component, support component, and load component are respectively mounted on the frame. The positioning component includes a positioning column and a first clamping component. The positioning column is provided with a positioning rod for engaging with a mounting hole on the steering gear housing. The first clamping component is provided with a clamp for movably abutting against the steering gear housing. The support component includes a base plate, a support plate, and a contour block fixedly disposed on the top surface of the support plate. The contour block is provided with a contour groove for placing a tie rod. One side of the base plate is detachably connected to the frame, and the other side of the base plate is provided with a slide rail. The bottom surface of the support plate is provided with a slider that slidably engages with the slide rail. The load component includes a tension sensor, a load block, and a load rod. One end of the load rod passes through the support plate and is connected to the tension sensor. The other end of the load rod is movably connected to the load block. The load block is fixedly mounted on the base plate.

[0008] Optionally, the load block is provided with a first through hole for the load rod to pass through, and the load block is provided with a second through hole communicating with the first through hole. A pressure block plug is installed in the second through hole, one end of the pressure block plug is threaded to the hole wall of the second through hole, and the other end of the pressure block plug abuts against the outer peripheral wall of the load rod.

[0009] Optionally, the end of the pressure block facing the load rod has an arc-shaped structure that matches the outer contour of the load rod.

[0010] Optionally, the load block is provided with an oil injection port communicating with the first through hole.

[0011] Optionally, the support plate is provided with a mounting bracket, the load rod includes a universal joint and a rod body, one end of the universal joint passes through the mounting bracket and is connected to a tension sensor, the other end of the universal joint is coaxially connected to the rod body, and the rod body is movably connected to the load block.

[0012] Optionally, the first clamping assembly includes a first cylinder and a first connecting plate. The positioning post includes a horizontal plate and a vertical plate perpendicularly connected to the horizontal plate. The horizontal plate is provided with the positioning rod. The cylinder body of the first cylinder is fixedly installed on the bottom surface of the horizontal plate. The piston rod of the first cylinder passes through the horizontal plate and is connected to the first connecting plate. The end face of the first connecting plate facing the positioning rod is provided with a first inclined surface. The end face of the chuck away from the positioning rod is provided with a second inclined surface that fits and abuts against the first inclined surface.

[0013] Optionally, a second clamping assembly is also included. The second clamping assembly includes a second cylinder and a second connecting plate. The cylinder body of the second cylinder is fixedly installed on the bottom surface of the support plate. The piston rod of the second cylinder passes through the support plate and is connected to the second connecting plate. The second connecting plate is provided with two parallel clamping plates. The contour block is provided with a third through hole that connects to the contour groove. The clamping plates can slide through the third through hole.

[0014] Optionally, the sidewall of the third through hole is provided with a sliding groove that slides with the clamping plate, and the clamping surfaces of the two clamping plates opposite each other are planes used to clamp the nuts on the pull rod.

[0015] The beneficial effects of this utility model are as follows: In use, the rack and pinion steering gear is placed on the test bench, and the mounting holes on the steering gear housing are positioned on the positioning pins. The positioning components consist of four sets, with the four positioning pins fixing the steering gear housing around its perimeter. Then, the steering gear tie rod is placed into the contour groove. By manually rotating the steering wheel, the tie rod moves horizontally to the left or right. The contour block drives the support plate to move synchronously, and the support plate drives the load tie rod to move. The load block applies a load to the tie rod through friction, and the load block applies friction to the load rod to simulate the tire's ground resistance. The tension sensor monitors the load force in real time, achieving accurate simulation of the steering gear load conditions under no-assist power steering conditions.

[0016] This invention abandons the servo motor loading method and uses a load block to apply resistance to the load rod. The load block dynamically simulates the tire's ground resistance through static friction, with no motor operating noise throughout the process. Furthermore, the natural frequency of the mechanical structure is far from the steering system's operating frequency band, completely avoiding interference from servo system noise and load unit resonance on the test results. Moreover, when the steering wheel is manually turned quickly, the horizontal movement of the rod drives the contour block, support plate, and load rod in a coordinated manner. The load block responds to displacement changes in real time through rigid mechanical transmission, and the direction and magnitude of the friction force switch instantaneously when the steering wheel turns left or right, overcoming the lag defect of hydraulic valves and ensuring no load failure throughout the entire process under rapid steering conditions. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the load simulation tooling for the gear and rack steering gear proposed in an embodiment of the present invention;

[0018] Figure 2 This is a partially enlarged view of the load simulation tooling for the rack and pinion steering gear proposed in an embodiment of this utility model;

[0019] Figure 3 This is a schematic diagram of the load block of the load simulation tooling for the rack and pinion steering gear proposed in an embodiment of this utility model;

[0020] Figure 4 This is a schematic diagram of the second clamping component of the rack and pinion steering gear load simulation tooling proposed in this embodiment of the present invention;

[0021] Figure 5 This is a schematic diagram of the assembly of the rack and pinion steering gear load simulation tooling proposed in this embodiment of the invention during testing.

[0022] The labels in the attached figures are as follows: 1. Stand; 2. Positioning assembly; 21. Positioning column; 211. Horizontal plate; 212. Vertical plate; 213. Positioning rod; 22. First clamping assembly; 221. First cylinder; 222. First connecting plate; 222a. First inclined plane; 223. Chuck; 223a. Second inclined plane; 3. Support assembly; 31. Base plate; 311. Slide rail; 32. Support plate; 321. Slider; 322. Mounting bracket; 33. Contouring block; 3 31. Contouring groove; 332. Slide groove; 4. Load assembly; 41. Tension sensor; 42. Load block; 421. First through hole; 422. Second through hole; 423. Oil inlet; 424. Pressure block plug; 43. Load rod; 431. Universal shaft; 432. Rod body; 5. Second clamping assembly; 51. Second cylinder; 52. Second connecting plate; 53. Clamping plate; 531. Clamping surface; 6. Rack and pinion steering gear; 61. Housing; 62. Tie rod. Detailed Implementation

[0023] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.

[0024] like Figures 1 to 5 As shown, this embodiment discloses a load simulation fixture for a rack and pinion steering gear, including a frame 1, a positioning component 2, a support component 3, and a load component 4. The positioning component 2, support component 3, and load component 4 are respectively mounted on the frame 1. The positioning component 2 includes a positioning post 21 and a first clamping component 22. The positioning post 21 is provided with a positioning rod 213 for engaging with a mounting hole on the steering gear housing 61. The first clamping component 22 is provided with a clamp 223 for movably abutting against the steering gear housing 61. The support component 3 includes a base plate 31, a support plate 32, and a fixing device. The top surface of the support plate 32 has a contour block 33, which is provided with a contour groove 331 for placing the pull rod 62. One side of the base plate 31 is detachably connected to the frame 1, and the other side of the base plate 31 is provided with a slide rail 311. The bottom surface of the support plate 32 is provided with a slider 321 that slides with the slide rail 311. The load assembly 4 includes a tension sensor 41, a load block 42 and a load rod 43. One end of the load rod 43 passes through the support plate 32 and is connected to the tension sensor 41. The other end of the load rod 43 is movably connected to the load block 42. The load block 42 is fixedly installed on the base plate 31. In use, the rack and pinion steering gear 6 is placed on the test bench 1, and the mounting holes on the steering gear housing 61 are positioned on the positioning pins 21 for positioning. The positioning assembly 2 consists of four sets, with the four positioning pins 21 fixing the steering gear housing 61 around its perimeter. Then, the steering gear tie rod 62 is placed into the contour groove 331. By manually rotating the steering wheel, the tie rod 62 moves horizontally to the left or right. The contour block 33 drives the support plate 32 to move synchronously, and the support plate 32 drives the load tie rod 62 to move. The load block 42 applies a load to the tie rod 62 through friction, and the load block 42 applies friction to the load rod 43 to simulate tire ground resistance. The tension sensor 41 monitors the load force in real time, achieving accurate simulation of the steering gear load conditions under no-assist power steering conditions. This embodiment abandons the servo motor loading method and uses a load block to apply resistance to the load tie rod. The load block dynamically simulates tire resistance to the ground through static friction, with no motor noise throughout the entire process. Furthermore, the natural frequency of its mechanical structure is far from the steering system's operating frequency, completely avoiding interference from servo system noise and load unit resonance on the test results. When the steering wheel is turned quickly by the operator, the horizontal movement of the tie rod drives the contour block, support plate, and load tie rod in a coordinated manner. The load block responds to displacement changes in real time through rigid mechanical transmission, and the direction and magnitude of the friction force switch instantaneously when the steering wheel turns left or right. This overcomes the lag in hydraulic valve response, ensuring the load remains unaffected throughout the entire process under rapid steering conditions.

[0025] In this embodiment, as Figure 3As shown, the load block 42 has a first through hole 421 through which the load rod 43 passes. The load block 42 also has a second through hole 422 communicating with the first through hole 421. A pressure block plug 424 is installed in the second through hole 422. One end of the pressure block plug 424 is threaded to the wall of the second through hole 422, and the other end of the pressure block plug 424 presses against the outer peripheral wall of the load rod 43. The end of the pressure block plug 424 away from the load rod 43 has an external thread, and the inner peripheral wall of the second through hole 422 has an internal thread that mates with the external thread. By screwing in or out the pressure block plug 424, the load force applied to the load rod 43 can be adjusted.

[0026] In this embodiment, as Figure 3 As shown, the end of the pressure block 424 facing the load rod 43 has an arc-shaped structure that matches the outer contour of the load rod 43. This increases the contact area between the pressure block 424 and the load rod 43, preventing localized wear caused by stress concentration.

[0027] In this embodiment, as Figure 3 As shown, the load block 42 is provided with an oil inlet 423 communicating with the first through hole 421. The service life of the pressure block plug 424 and the load rod 43 can be increased by adding grease into the oil inlet 423.

[0028] In this embodiment, as Figure 2 As shown, the support plate 32 is provided with a mounting bracket 322, and the load rod 43 includes a universal joint 431 and a rod 432. One end of the universal joint 431 passes through the mounting bracket 322 and is connected to the tension sensor 41, while the other end of the universal joint 431 is coaxially connected to the rod 432. The rod 432 is movably connected to the load block 42. The universal joint 431 is a straight-rod ball joint bearing, which is existing technology. The support plate 32 is vertically provided with a connecting plate, and the universal joint 431 provides angular swing space to prevent jamming when the support plate 32 and the rod 432 are not coaxial. In other embodiments, the universal joint 431 and the tension sensor 41 can be fixedly connected to the mounting bracket 322 respectively.

[0029] In this embodiment, as Figure 2 and 5As shown, the first clamping assembly 22 includes a first cylinder 221 and a first connecting plate 222. The positioning post 21 includes a horizontal plate 211 and a vertical plate 212 perpendicularly connected to the horizontal plate 211. The horizontal plate 211 is provided with the positioning rod 213. The cylinder body of the first cylinder 221 is fixedly installed on the bottom surface of the horizontal plate 211. The piston rod of the first cylinder 221 passes through the horizontal plate 211 and is connected to the first connecting plate 222. The end face of the first connecting plate 222 facing the positioning rod 213 is provided with a first inclined surface 222a. The end face of the chuck 223 away from the positioning rod 213 is provided with a second inclined surface 223a that fits and abuts against the first inclined surface 222a. When the steering gear housing 61 is placed on the positioning rod 213 through the mounting hole, since the diameter of the positioning hole is larger than the diameter of the positioning rod 213, in order to ensure that the steering gear housing 61 remains stable, the piston rod of the first cylinder 221 rises, and the first inclined surface 222a of the first connecting plate 222 pushes the second inclined surface 223a, causing the chuck 223 to move towards the positioning rod 213, thereby clamping the steering gear housing 61. The first clamping assembly 22 can be a wedge-type expansion clamp.

[0030] In this embodiment, as Figure 2 and 4 As shown, it also includes a second clamping assembly 5, which includes a second cylinder 51 and a second connecting plate 52. The cylinder body of the second cylinder 51 is fixedly installed on the bottom surface of the support plate 32. The piston rod of the second cylinder 51 passes through the support plate 32 and connects to the second connecting plate 52. The second connecting plate 52 is provided with two parallel clamping plates 53. The contour block 33 is provided with a third through hole communicating with the contour groove 331. The clamping plates 53 can slide through the third through hole. The side wall of the third through hole is provided with a sliding groove 332 that slides with the clamping plates 53. The clamping surfaces 531 of the two clamping plates 53 opposite each other are planes for clamping the nuts on the pull rod 62. When the pull rod 62 is placed in the contour groove 331, the second cylinder 51 drives the second connecting plate 52 to rise. The second connecting plate 52 drives the two clamping plates 53 to move along the sliding groove 332, so that the clamping plates 53 clamp the two vertical sides of the hexagonal nuts on the pull rod 62, thus fixing the pull rod 62 inside the sliding groove 332.

[0031] 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 load simulation fixture for a rack and pinion steering gear, characterized in that, It includes a platform, a positioning component, a support component, and a load component, wherein the positioning component, support component, and load component are respectively mounted on the platform. The positioning assembly includes a positioning post and a first clamping assembly. The positioning post is provided with a positioning rod for engaging with a mounting hole on the steering gear housing, and the first clamping assembly is provided with a clamp for movably abutting against the steering gear housing. The support assembly includes a base plate, a support plate, and a contour block fixed on the top surface of the support plate. The contour block has a contour groove for placing a pull rod. One side of the base plate is detachably connected to the frame, and the other side of the base plate is provided with a slide rail. The bottom surface of the support plate is provided with a slider that slides with the slide rail. The load assembly includes a tension sensor, a load block, and a load rod. One end of the load rod passes through a support plate and is connected to the tension sensor, while the other end of the load rod is movably connected to the load block. The load block is fixedly installed on the base plate.

2. The load simulation fixture for a rack and pinion steering gear according to claim 1, characterized in that, The load block has a first through hole through which the load rod passes, and a second through hole communicating with the first through hole. A pressure block plug is installed in the second through hole. One end of the pressure block plug is threaded to the hole wall of the second through hole, and the other end of the pressure block plug abuts against the outer peripheral wall of the load rod.

3. The load simulation fixture for a rack and pinion steering gear according to claim 2, characterized in that, The end of the pressure block facing the load rod has an arc-shaped structure that matches the outer contour of the load rod.

4. The load simulation fixture for a rack and pinion steering gear according to claim 2, characterized in that, The load block is provided with an oil injection port that communicates with the first through hole.

5. The load simulation fixture for a rack and pinion steering gear according to claim 1, characterized in that, The support plate is provided with a mounting frame, and the load rod includes a universal joint and a rod body. One end of the universal joint passes through the mounting frame and is connected to a tension sensor, and the other end of the universal joint is coaxially connected to the rod body. The rod body is movably connected to the load block.

6. The load simulation fixture for a rack and pinion steering gear according to claim 1, characterized in that, The first clamping assembly includes a first cylinder and a first connecting plate. The positioning post includes a horizontal plate and a vertical plate perpendicularly connected to the horizontal plate. The horizontal plate is provided with the positioning rod. The cylinder body of the first cylinder is fixedly installed on the bottom surface of the horizontal plate. The piston rod of the first cylinder passes through the horizontal plate and is connected to the first connecting plate. The end face of the first connecting plate facing the positioning rod is provided with a first inclined surface. The end face of the clamp away from the positioning rod is provided with a second inclined surface that fits and abuts against the first inclined surface.

7. The load simulation fixture for a rack and pinion steering gear according to claim 1, characterized in that, It also includes a second clamping assembly, which includes a second cylinder and a second connecting plate. The cylinder body of the second cylinder is fixedly installed on the bottom surface of the support plate. The piston rod of the second cylinder passes through the support plate and is connected to the second connecting plate. The second connecting plate is provided with two parallel clamping plates. The contour block is provided with a third through hole that connects to the contour groove. The clamping plates can slide through the third through hole.

8. The load simulation fixture for a rack and pinion steering gear according to claim 7, characterized in that, The sidewall of the third through hole is provided with a sliding groove that slides with the clamping plate, and the clamping surfaces of the two clamping plates opposite each other are planes used to clamp the nuts on the pull rod.

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