Lead screw support device, power steering system, and vehicle
By using rolling bearings with at least two rows of rolling elements in the screw support device, combined with shims to reduce friction, the problem of high friction in existing rolling bearings is solved, thereby improving system efficiency and lifespan.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ROBERT BOSCH AUTOMOTIVE STEERING JINAN CO LTD
- Filing Date
- 2025-07-28
- Publication Date
- 2026-07-24
AI Technical Summary
In existing ball screw power steering systems, the rolling bearings have high friction, which affects system efficiency and lifespan.
Rolling bearings with at least two rows of rolling elements are arranged at intervals in the radial direction of the screw to reduce friction and increase bearing load capacity. Combined with a shim design, wear is reduced.
It reduces the unexpected friction of rolling bearings, improves the overall lifespan and efficiency of the machine, and enhances the axial load-bearing capacity of the bearings.
Smart Images
Figure CN224546072U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of automotive parts, and more specifically, relates to a lead screw support device, a power steering system equipped with the lead screw support device, and a vehicle equipped with the power steering system. Background Technology
[0002] The information provided in this section is for the purpose of generally presenting the background of this disclosure. To the extent described in this section, the work of the currently named inventors and aspects of the description that may not constitute prior art at the time of filing are neither explicitly nor implicitly considered to be prior art of this disclosure.
[0003] In a ball screw power steering system, the ball screw, as one of the core components, is crucial to the system's output characteristics. Specifically, the ball screw and nut drive the ball screw to rotate, causing the rack to move axially, ultimately achieving the vehicle's steering function through mechanical mechanisms such as tie rods, steering knuckles, wheel hubs, and tires. Utility Model Content
[0004] According to this application, a lead screw support device is provided, comprising:
[0005] Casing; and
[0006] A lead screw, the end of which is rotatably mounted within the housing via a rolling bearing.
[0007] The rolling bearing includes a cage mounted at the end of the lead screw and at least two rows of rolling elements disposed on the cage. One row of the at least two rolling elements includes at least two first rolling elements that are rotatable about the radial direction of the lead screw and are spaced apart circumferentially along the lead screw. The other row of the at least two rolling elements includes at least two second rolling elements that are rotatable about the radial direction of the lead screw and are spaced apart circumferentially along the lead screw. The second rolling elements are arranged radially outside the first rolling elements of the lead screw.
[0008] Optionally, in the lead screw support device as described above, the lead screw has a first end and a second end, and the rolling bearing includes a first rolling bearing and a second rolling bearing, wherein the first rolling bearing is located at the first end of the lead screw, and the second rolling bearing is located at the second end of the lead screw.
[0009] Optionally, in the lead screw support device as described above, the first rolling bearing and the second rolling bearing have the same shape and size.
[0010] Optionally, in the lead screw support device as described above, a first washer is provided between the rolling bearing and the end of the lead screw, and a second washer is provided between the rolling bearing and the housing (100), wherein the first rolling element and the second rolling element can simultaneously contact the first washer and the second washer.
[0011] Optionally, in the lead screw support device as described above, the first rolling element and the first rolling element have the same shape and size; and / or
[0012] The number of the first rolling elements and the second rolling elements are the same and they are arranged in a one-to-one correspondence in the radial direction of the lead screw, and the first rolling elements are arranged at equal intervals along the circumferential direction of the lead screw.
[0013] Optionally, in the lead screw support device as described above, the rolling bearing is a needle roller bearing, and the first rolling element and the second rolling element are cylindrical needle rollers.
[0014] Optionally, in the lead screw support device as described above, the first rolling element and the second rolling element are made of metal; and / or
[0015] The cage is made of nylon fiberglass material.
[0016] Optionally, in the lead screw support device as described above, the first washer is a shaped washer, and the second washer is a flat washer.
[0017] In addition, according to this application, a power steering system is also provided, wherein the power steering system is provided with the aforementioned lead screw support device.
[0018] In addition, according to this application, a vehicle is also provided, the vehicle being equipped with the aforementioned power steering system.
[0019] It is understood that the screw support device of this application, by employing at least two rows of rolling elements, can reduce the unexpected friction of the rolling bearing and improve the overall life of the machine. Attached Figure Description
[0020] The disclosure of this application will become more readily understood with reference to the accompanying drawings. It will be readily understood by those skilled in the art that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this application. Furthermore, similar numbers in the drawings are used to denote similar components, wherein:
[0021] Figure 1 A schematic cross-sectional view of the screw support device disclosed in this application is shown as an example;
[0022] Figure 2An exemplary schematic diagram of the structure of the rolling bearing of the screw support device disclosed in this application is shown; and
[0023] Figure 3 An exemplary view shows a partially enlarged cross-sectional schematic diagram of the end of the lead screw of the lead screw support device disclosed in this application. Detailed Implementation
[0024] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. First, it should be noted that the directional terms such as up, down, left, right, front, back, inner, outer, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. They are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive terms. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0025] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," "some examples," or "possible implementation," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0026] Figure 1 The structure of the lead screw support device disclosed in this application is shown. From Figure 1 and Figure 2Clearly, the lead screw support device 10 consists of a housing 100, a lead screw 200, a rolling bearing 300, and an output shaft 400. The end of the lead screw 200 is rotatably mounted within the housing 100 via the rolling bearing 300. The output shaft 400 (also called a sector shaft) is also located within the housing 100 and connected to the lead screw 200 via a piston (not shown), allowing the output shaft 400 to rotate under the drive of the lead screw 200, thereby transmitting torque to the wheels to achieve vehicle steering. The rolling bearing 300 includes a disc-shaped or substantially disc-shaped cage 310 and double rows of rolling elements disposed on the cage 310. The cage 310 is mounted or fitted onto the end of the lead screw 200, and the inner hole of the cage 310 can maintain a certain gap with the lead screw 200; that is, the cage 310 does not rotate with the lead screw 200. Figure 2 As shown, one row of rolling elements in the double-row configuration includes at least two first rolling elements 320 that are rotatable about the radial direction of the lead screw 200 and are arranged at intervals along the circumference of the lead screw 200. The other row of rolling elements includes at least two second rolling elements 330 that are rotatable about the radial direction of the lead screw 200 and are arranged at intervals along the circumference of the lead screw 200. It should be noted that in this application, the outermost ends of the same row of rolling elements, such as at least two second rolling elements 330, in the radial direction of the lead screw 200 do not necessarily fall on the same circumferential line centered on the axis of the lead screw 200. Furthermore, the second rolling elements 330 are arranged radially outside the first rolling elements 320, that is, the outermost end of the second rolling elements 330 in the radial direction of the lead screw 200 is located outside the outermost end of the first rolling elements 320 in the radial direction of the lead screw 200. Of course, those skilled in the art will readily understand that, in addition to... Figure 2 In addition to the double-row rolling elements shown, the rolling bearing 300 in the screw support device 10 of this application can also employ three, four, or more rows of rolling elements. It should be noted that by employing a design with at least two rows of rolling elements, the unexpected frictional force of the rolling bearing can be reduced, and the rolling bearing can withstand greater axial loads, thereby improving the overall machine efficiency.
[0027] In other optional embodiments, in conjunction with the above embodiments, the lead screw 200 has a first end 210 and a second end 220, such as... Figure 1As shown. The rolling bearing 300 includes a first rolling bearing 301 and a second rolling bearing 302, wherein the first rolling bearing 301 is located at the first end 210 of the lead screw 200, and the second rolling bearing 302 is located at the second end 220 of the lead screw 200. Further, the first rolling bearing 301 and the second rolling bearing 302 may be configured to have the same shape and size and be symmetrically arranged at both ends of the lead screw 200.
[0028] Continue to refer to Figure 3 A first washer 500 is provided between the rolling bearing 300 and the end of the lead screw 200, and a second washer 600 is provided between the rolling bearing 300 and the housing 100, thereby reducing wear between the rolling bearing 300 and the housing 100 and between the rolling bearing 300 and the end of the lead screw 200. Specifically, the first washer 500 is fixedly connected to the end of the lead screw 200, and the second washer 600 is fixed to the housing 100. When the lead screw 200 rotates, the first rolling element 320 and the second rolling element 330 of the rolling bearing 300 can simultaneously contact the first washer 500 and the second washer 600, so that the cage 310 rotates together under the drive of the first rolling element 320 and the second rolling element 330. For example, the first washer 500 is an irregularly shaped washer, and the second washer 600 is a flat washer.
[0029] For ease of manufacturing, the first rolling element 320 and the second rolling element 330 are identical in shape and size. For example, the rolling bearing 300 is a needle roller bearing, and the first rolling element 320 and the second rolling element 330 are cylindrical needle rollers. That is, the first rolling element 320 and the second rolling element 330 are capable of rotating about their own axis. In this case, the center of the first rolling element 320 is located on a first circumference centered on the axis of the lead screw 200, and the center of the second rolling element 330 is located on a second circumference centered on the axis of the lead screw 200, wherein the radius of the second circumference is larger than the radius of the first circumference. For another example, the first rolling element 320 and the second rolling element 330 can be made of a metallic material, such as bearing steel. As another example, the cage 310 is made of nylon fiberglass material. Furthermore, the number of the first rolling elements 320 and the second rolling elements 330 are the same, and they are arranged in a one-to-one correspondence in the radial direction of the lead screw 200. Taking a needle roller bearing in which both the first and second rolling elements are needle rollers as an example, the axes of the first rolling elements 320 and the second rolling elements 330, which are arranged in a one-to-one correspondence, are located in the same radial direction of the lead screw 200, and the first rolling elements 320 are arranged at equal intervals along the circumferential direction of the lead screw 200. Figure 2 As shown. Of course, taking a needle roller bearing in which both the first and second rolling elements are needle rollers as an example, it is also feasible to set the axes of the first rolling element 320 and the second rolling element 330 at a certain distance.
[0030] Furthermore, this application also provides a power steering system, which includes the aforementioned lead screw support device 10. The technical improvements and beneficial effects of this power steering system are the same as those of the lead screw support device 10, therefore, a detailed description of the power steering system is not required.
[0031] In addition, this application also provides a vehicle equipped with the aforementioned power steering system. The vehicle can be a private car, commercial vehicle, taxi, bus, minibus, or coach, or any other type of vehicle.
[0032] The foregoing has provided several specific embodiments to illustrate the lead screw support device, the power steering system equipped with the lead screw support device, and the vehicle equipped with the power steering system of this application. These examples are only for illustrating the principles and implementation methods of this application and are not intended to limit the application. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and scope of this application. Therefore, all equivalent technical solutions should fall within the scope of this application and be defined by the claims of this application.
Claims
1. A lead screw support device, comprising: Casing (100); as well as A lead screw (200), the end of which is rotatably mounted in the housing (100) via a rolling bearing (300). The rolling bearing (300) is characterized in that it includes a cage (310) mounted at the end of the lead screw (200) and at least two rows of rolling elements disposed on the cage (310). One row of the at least two rows of rolling elements includes at least two first rolling elements (320) that are rotatable about the radial direction of the lead screw (200) and are arranged at intervals along the circumference of the lead screw (200). The other row of the at least two rows of rolling elements includes at least two second rolling elements (330) that are rotatable about the radial direction of the lead screw (200) and are arranged at intervals along the circumference of the lead screw (200). The second rolling elements (330) are arranged radially outside the first rolling elements (320) of the lead screw (200).
2. The lead screw support device according to claim 1, characterized in that, The lead screw (200) has a first end (210) and a second end (220), and the rolling bearing (300) includes a first rolling bearing (301) and a second rolling bearing (302), wherein the first rolling bearing (301) is located at the first end (210) of the lead screw (200), and the second rolling bearing (302) is located at the second end (220) of the lead screw (200).
3. The lead screw support device according to claim 2, characterized in that, The first rolling bearing (301) and the second rolling bearing (302) have the same shape and size.
4. The lead screw support device according to any one of claims 1-3, characterized in that, A first washer (500) is provided between the end of the rolling bearing (300) and the lead screw (200), and a second washer (600) is provided between the rolling bearing (300) and the housing (100). The first rolling element (320) and the second rolling element (330) can simultaneously contact the first washer (500) and the second washer (600).
5. The lead screw support device according to any one of claims 1-3, characterized in that, The first rolling element (320) and the second rolling element (330) have the same shape and size; and / or The number of the first rolling element (320) and the second rolling element (330) are the same and they are arranged in a one-to-one correspondence in the radial direction of the lead screw (200), and the first rolling element (320) is arranged at equal intervals along the circumferential distance of the lead screw (200).
6. The lead screw support device according to claim 5, characterized in that, The rolling bearing (300) is a needle roller bearing, and the first rolling element (320) and the second rolling element (330) are cylindrical needle rollers.
7. The lead screw support device according to any one of claims 1-3, characterized in that, The first rolling element (320) and the second rolling element (330) are made of metallic material; and / or The retainer (310) is made of nylon fiberglass material.
8. The lead screw support device according to claim 4, characterized in that, The first gasket (500) is a shaped gasket, and the second gasket (600) is a flat gasket.
9. A power steering system, characterized in that, The power steering system is provided with a lead screw support device (10) according to any one of claims 1-8.
10. A vehicle, characterized in that, The vehicle is equipped with the power steering system according to claim 9.