Dual pinion electric power steering device for passenger car

Abstract

The utility model discloses a double pinion type electric power steering device for passenger car, including rack housing, first upper cover, power -assisted housing and second upper cover, the first sealing piece for realizing axial seal is arranged between rack housing with first upper cover, and the first sealing groove that lets first sealing piece inserts is arranged on the end surface of first upper cover and rack housing is pasted, and a plurality of convexes are arranged on first sealing piece, and the opposite two inner wall surfaces of convex and first sealing groove are contacted. Double pinion type electric power steering device for passenger car of the utility model, through the sealing groove of accommodating sealing piece that first upper cover and rack housing pasted end surface are equipped with, sealing piece realizes axial seal, and the cutting circle phenomenon will not appear in the assembly process, can improve the reliability of sealing.

Description

Technical Field

[0001] This utility model belongs to the technical field of vehicle steering systems. Specifically, this utility model relates to a dual pinion electric steering device for passenger cars. Background Technology

[0002] DP-EPS (Dual Pinion Electric Power Steering), a key technology in modern automotive steering systems, integrates advancements from mechanical engineering, electronic control, and materials science. Mechanically, it borrows the basic architecture of traditional rack and pinion steering systems, innovating the power assist transmission path through a dual pinion design, thus improving steering efficiency and precision. In terms of electronic control, it combines advanced sensor technology and motor drive algorithms to achieve precise control over the magnitude and direction of power assist. Advances in materials science have made it possible to achieve lightweight, high-strength housings and wear-resistant gear and rack materials for DP-EPS. Currently, DP-EPS is widely used in various passenger cars and some commercial vehicles, becoming one of the mainstream technologies in automotive steering systems.

[0003] DP-EPS (Dual Pinion Electric Power Steering) is a key component of automotive steering systems, achieving precise power assistance through the collaboration of mechanical and electronic systems. Its structure mainly consists of a dual pinion mechanism, a motor, a reduction gear, a torque sensor, and an electronic control unit (ECU). The steering pinion meshes with the rack; the power assist pinion is connected to the motor output shaft and, after passing through the reduction gear, works together with the main pinion on the rack.

[0004] During operation, the driver turns the steering wheel, and the torque sensor detects the magnitude and direction of the steering force, transmitting the signal to the ECU. The ECU calculates the required power assist based on data such as vehicle speed and torque, and controls the motor to output the corresponding torque. The motor torque is amplified by a reduction mechanism and transmitted to the rack via a pinion gear. This torque is then combined with the driver's input steering force, driving the rack to steer the wheels. At lower vehicle speeds, the system provides greater power assist for easier steering; at higher speeds, the power assist is reduced to enhance steering stability. This unique dual-pinion gear design achieves efficient coordination between mechanical transmission and electric power assist, improving driving comfort and safety.

[0005] Existing dual-pinion electric power steering systems have the following problems:

[0006] The sealing method between the top cover and the rack housing is radial sealing. During the assembly of the radial sealing ring, due to the manufacturing error of the wire diameter, the ring is prone to early damage during the assembly process. Subsequently, it is prone to early failure when working in high temperature, high humidity and vibration environment, resulting in water or foreign matter intrusion and damage to the components.

[0007] Chinese Patent Application No. 202410829761.1 discloses an electric power steering device, which includes a steering gear body, two power steering motor assemblies, an active cone hub assembly, and a driven cone hub assembly. It adopts a modular structure, with the driven bevel gear and the active bevel gear integrated into the active cone hub assembly and the driven cone hub assembly, respectively. Through the assembly relationship between the modules, the meshing of the bevel gear pair is ensured. The adjusting ring can rotate relative to the end cover and drive the central shaft to move along its axial direction to adjust the meshing clearance between the driven bevel gear and the active bevel gear, ensuring the correct meshing of the bevel gear pair and improving the convenience and accuracy of bevel gear pair clearance adjustment.

[0008] A dual pinion electric power steering system for passenger vehicles is provided, particularly concerning improved sealing reliability. Utility Model Content

[0009] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention provides a dual-pinion electric power steering system for passenger vehicles, with the purpose of improving sealing reliability.

[0010] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a dual pinion electric steering device for passenger vehicles, comprising a rack housing, a first upper cover, a power steering housing, and a second upper cover. A first sealing element for axial sealing is provided between the rack housing and the first upper cover. A first sealing groove is provided on the end face of the first upper cover that fits against the rack housing, allowing the first sealing element to be embedded. Multiple protrusions are provided on the first sealing element, and the protrusions contact the two opposite inner wall surfaces of the first sealing groove.

[0011] The rack housing and the first top cover are connected by a first screw. The first top cover has multiple screw through holes, and the rack housing has multiple threaded holes.

[0012] Two of the first screws are provided.

[0013] A screw plug is provided on the rack housing, and the screw plug is threadedly connected to the rack housing. A second sealing groove is provided on the rack housing for the second sealing element to be embedded. The second sealing element is sandwiched between the screw plug and the rack housing.

[0014] The screw plug is coated with sealant.

[0015] A third sealing element is provided between the auxiliary housing and the second upper cover, and the second upper cover is provided with a third sealing groove for the third sealing element to be embedded.

[0016] The second upper cover is provided with elastic buckles, and the auxiliary housing is provided with an annular arc groove. The elastic buckles are embedded in the annular arc groove, and multiple elastic buckles are provided.

[0017] Four elastic buckles are provided.

[0018] The elastic buckle is arc-shaped.

[0019] The second top cover has multiple disassembly slots on its end face.

[0020] The present invention relates to a dual pinion electric steering device for passenger vehicles. The first upper cover has a sealing groove on the mating end face of the rack housing to accommodate a sealing element. The sealing element achieves axial sealing, and no ring cutting occurs during assembly, which can improve the reliability of the seal. Attached Figure Description

[0021] This manual includes the following figures, which illustrate the following:

[0022] Figure 1 This is a partial structural schematic diagram of the dual pinion electric steering device for passenger vehicles according to this utility model;

[0023] Figure 2 This is another partial structural schematic diagram of the dual pinion electric steering device for passenger vehicles according to this utility model;

[0024] Figure 3 This is the front view of the second top cover;

[0025] Figure 4 This is a side view of the second top cover;

[0026] Figure 5 This is a schematic diagram of the structure of the first sealing element;

[0027] The markings in the diagram are as follows: 1. First top cover; 2. Second top cover; 3. First screw; 4. First seal; 401. Seal body; 402. Protrusion; 5. Second seal; 6. Third seal; 7. Spindle assembly; 8. Worm gear; 9. Rack housing; 10. Auxiliary housing; 11. Plug; 12. Elastic buckle; 13. Disassembly slot. Detailed Implementation

[0028] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings, in order to help those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of this utility model, and to facilitate its implementation.

[0029] It should be noted that in the following embodiments, the terms "first," "second," and "third" do not represent an absolute distinction in structure and / or function, nor do they represent the order of execution; they are merely for the convenience of description.

[0030] like Figures 1 to 5As shown, this utility model provides a dual pinion electric steering device for passenger vehicles, including a main shaft assembly 7, a rack housing 9, a first upper cover 1, a power steering housing 10, and a second upper cover 2. A first sealing element 4 for axial sealing is provided between the rack housing 9 and the first upper cover 1. A first sealing groove is provided on the end face of the first upper cover 1 that fits against the rack housing 9, allowing the first sealing element 4 to be embedded. A plurality of protrusions 402 are provided on the first sealing element 4, and the protrusions 402 are in contact with the two opposite inner wall surfaces of the first sealing groove.

[0031] Specifically, such as Figure 1 As shown, the first upper cover 1 and the rack housing 9 are clearance fit. A worm gear 8 is installed inside the rack housing 9. The spindle assembly 7 is connected to one end of the worm gear 8 and passes through the first upper cover 1. The rack housing 9 and the first upper cover 1 are connected by a first screw 3. The first upper cover 1 has multiple screw through holes, and the rack housing 9 has multiple threaded holes.

[0032] In this embodiment, two first screws 3 are provided, the first upper cover 1 is provided with two screw through holes, and the rack housing 9 is provided with two threaded holes.

[0033] like Figure 1 and Figure 5 As shown, the end face of the first sealing element 4 on the first upper cover 1 is in contact with one end face of the rack housing 9. These two end faces are located in a plane perpendicular to the axis of the main shaft assembly 7. The first sealing groove is an annular groove extending along the entire circumference on the end face of the first upper cover 1. The first sealing element 4 has a protrusion 402 that is wider than the sealing groove of the upper cover. After it is assembled into the first upper cover 1, it is not easy to detach from the first upper cover 1 during handling. After assembly, the first upper cover 1 and the rack housing 9 are connected together by two first screws 3. The first sealing element 4 is axially compressed to form a sealing band between the first upper cover 1 and the rack housing 9.

[0034] like Figure 1 and Figure 5As shown, the first sealing element 4 includes a sealing element body 401 and protrusions 402 fixedly disposed on the sealing element body 401. The sealing element body 401 has a circular structure, and the protrusions 402 are fixedly disposed on the outer and inner sides of the sealing element body 401. All protrusions 402 disposed on the outer side of the sealing element body 401 extend outward toward the outer side of the sealing element body 401, and are arranged sequentially along the circumference of the sealing element body 401. All the outer protrusions 402 are in contact with the inner wall surface of the first sealing groove. All protrusions 402 disposed on the inner side of the sealing element body 401 extend inward toward the inner side of the sealing element body 401, and are arranged sequentially along the circumference of the sealing element body 401. All the inner protrusions 402 are in contact with the other inner wall surface of the first sealing groove. Each inner protrusion 402 is arranged opposite to one outer protrusion 402, and the sealing element body 401 is located between every two oppositely arranged protrusions 402. The sealing body 401 is easily placed in the first sealing groove. The sealing body 401 is sandwiched between the first upper cover 1 and the rack housing 9, and plays a sealing role.

[0035] like Figure 1 As shown, a screw plug 11 is provided on the rack housing 9, and the screw plug 11 is threadedly connected to the rack housing 9. The rack housing 9 has a second sealing groove for the second sealing element 5 to be embedded in. The second sealing element 5 is sandwiched between the screw plug 11 and the rack housing 9. The screw plug 11 provides axial positioning for the worm gear 8. The second sealing groove is an annular groove extending along the entire circumference on the outer surface of the screw plug 11. After the screw plug 11 is assembled, the second sealing element 5 is subjected to radial compression to form a sealing band. To prevent foreign objects from entering the threads, sealant is applied to the screw plug 11 during assembly, providing double-layer sealing protection and reducing the failure rate of subsequent seal failure.

[0036] like Figure 2 As shown, the inner cavity of the second upper cover 2 and the auxiliary housing 10 are clearance fit, and a third sealing member 6 is provided between the auxiliary housing 10 and the second upper cover 2. The second upper cover 2 is provided with a third sealing groove for the third sealing member 6 to be embedded.

[0037] like Figures 2 to 4 As shown, the second upper cover 2 is provided with an elastic buckle 12, and the auxiliary housing 10 is provided with an annular arc groove. The elastic buckle 12 is embedded in the annular arc groove, and multiple elastic buckles 12 are provided.

[0038] In this embodiment, four elastic buckles 12 are provided, and the elastic buckles 12 are arc-shaped.

[0039] like Figures 2 to 4 As shown, the end face of the second upper cover 2 is provided with multiple disassembly slots 13, which facilitates subsequent product maintenance and disassembly, improves assembly processability, and reduces maintenance costs and difficulty.

[0040] During assembly, the sealing element is first installed in the sealing groove of the second upper cover 2, and then the second upper cover 2 is assembled into the inner cavity of the power-assisted housing 10. The third sealing element 6 is subjected to radial compression to form a sealing band to isolate the inner and outer cavities of the power-assisted housing 10. The second upper cover 2 has 4 arc-shaped elastic buckles 12 along the circumferential direction, and 4 disassembly slots are designed on the end face. The inner cavity of the power-assisted housing 10 has an annular arc groove. After assembly, the elastic buckles 12 are embedded in the arc groove of the power-assisted housing 10 to play a role in axial fixation and preventing detachment.

[0041] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention; or the direct application of the inventive concept and technical solution to other situations without modification, are all within the protection scope of the present invention.

Claims

1. A dual-pinion electric steering system for passenger vehicles, comprising a rack housing, a first upper cover, a power steering housing, and a second upper cover, characterized in that: A first sealing element for axial sealing is provided between the rack housing and the first upper cover. A first sealing groove is provided on the end face of the first upper cover that fits with the rack housing, allowing the first sealing element to be embedded. The first sealing element is provided with multiple protrusions, which contact the two opposite inner wall surfaces of the first sealing groove.

2. The dual pinion electric power steering system for passenger vehicles according to claim 1, characterized in that: The rack housing and the first top cover are connected by a first screw. The first top cover has multiple screw through holes, and the rack housing has multiple threaded holes.

3. The dual pinion electric power steering system for passenger vehicles according to claim 2, characterized in that: Two of the first screws are provided.

4. The dual pinion electric power steering system for passenger vehicles according to any one of claims 1 to 3, characterized in that: A screw plug is provided on the rack housing, and the screw plug is threadedly connected to the rack housing. A second sealing groove is provided on the rack housing for the second sealing element to be embedded. The second sealing element is sandwiched between the screw plug and the rack housing.

5. The dual pinion electric power steering system for passenger vehicles according to claim 4, characterized in that: The screw plug is coated with sealant.

6. The dual pinion electric power steering system for passenger vehicles according to any one of claims 1 to 3, characterized in that: A third sealing element is provided between the auxiliary housing and the second upper cover, and the second upper cover is provided with a third sealing groove for the third sealing element to be embedded.

7. The dual pinion electric power steering system for passenger vehicles according to claim 6, characterized in that: The second upper cover is provided with elastic buckles, and the auxiliary housing is provided with an annular arc groove. The elastic buckles are embedded in the annular arc groove, and multiple elastic buckles are provided.

8. The dual pinion electric power steering system for passenger vehicles according to claim 7, characterized in that: Four elastic buckles are provided.

9. The dual pinion electric power steering system for passenger vehicles according to claim 7, characterized in that: The elastic buckle is arc-shaped.

10. The dual pinion electric power steering system for passenger vehicles according to claim 6, characterized in that: The second top cover has multiple disassembly slots on its end face.

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