Steer-by-wire actuator for commercial vehicle

Abstract

The utility model discloses a commercial vehicle steer-by-wire actuator which comprises a lower shell, an upper shell, a steering lead screw and an end cover, the lower shell and the upper shell are fixedly connected through a screw, the steering lead screw is installed in the lower shell through a double-row bearing, the upper end of the steering lead screw is inserted into the upper shell, the upper end of the upper shell is fixedly connected with the end cover through a screw, and the end cover is fixedly connected with the steering lead screw. A positioning seat is arranged in the end cover and installed in the end cover through a positioning bearing, a positioning center shaft is arranged in the center of the lower surface of the positioning seat and inserted into a center hole in the upper end of a steering lead screw, an adjusting gasket is arranged between the positioning seat and the steering lead screw, and an angle sensor is installed at the upper end of the steering lead screw. A worm gear is arranged in the upper shell and installed on the steering lead screw. On the basis of the existing structure, a torsion rod spring, a torque angle driver and an input shaft hand power end are omitted; the angle sensor is directly arranged on the steering lead screw, and the steering stroke is controlled and output by collecting the rotated angle of the angle sensor.

Description

Technical Field

[0001] This utility model relates to the field of commercial vehicle steering actuation technology, specifically a commercial vehicle steer-by-wire actuator. Background Technology

[0002] It solves the persistent problems of large free play, high-speed drift, and poor steering precision in traditional hydraulic power steering systems, and supports the expansion of advanced driving functions, such as LKA lane keeping assist, APA automatic parking assist, and autonomous driving.

[0003] To achieve "additional" functionality, an EPS system is essential. Power steering is achieved by integrating a motor control unit into a recirculating ball mechanical steering gear, employing a worm gear reduction mechanism. However, in long-wheelbase multi-axle trucks, a controllable steering actuator is required to support steering of the last axle, thereby improving steering maneuverability. Traditional hydraulic steering, besides requiring numerous auxiliary components such as the power steering source, piping, and reservoir, cannot achieve the necessary angle control and active return-to-center functionality. Therefore, a steer-by-wire actuator can precisely solve these problems. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the existing defects and provide a steer-by-wire actuator for commercial vehicles. Based on the existing structure, the torsion bar spring and torque angle transmission device are eliminated, and the input shaft hand force end is replaced. Instead, an angle sensor is directly installed on the steering screw. By collecting the angle of rotation of the angle sensor, the output steering stroke is controlled, which can effectively solve the problems in the background technology.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a commercial vehicle steer-by-wire actuator, comprising a lower housing, an upper housing, a steering screw, and an end cover. The lower housing and the upper housing are fixedly connected by screws. The steering screw is mounted in the lower housing via a double-row bearing, and the upper end of the steering screw is inserted into the upper housing. The upper end of the upper housing is fixedly connected to the end cover by screws. A positioning seat is provided in the end cover, and the positioning seat is mounted in the end cover via a positioning bearing. A positioning center shaft is provided at the center of the lower surface of the positioning seat, and the positioning center shaft is inserted into the center hole at the upper end of the steering screw. An adjusting shim is provided between the positioning seat and the steering screw. An angle sensor is installed at the upper end of the steering screw.

[0006] Furthermore, a worm gear is installed in the upper housing and mounted on the steering screw. The worm gear meshes with the worm. A control motor is installed on the outside of the upper housing, and the output shaft of the control motor is connected to the worm.

[0007] Furthermore, a steering nut is provided on the steering screw, and the steering nut is connected to a rocker arm shaft, the other end of which is connected to a rocker arm.

[0008] Furthermore, a bearing housing is provided at the upper end of the lower housing, and two double-row bearings are provided, one of which is installed at the bottom of the lower housing, and the other is installed in the bearing housing.

[0009] Furthermore, the positioning seat is configured as a convex structure, with its circumferential direction abutting against the inner ring of the positioning bearing.

[0010] Compared with the prior art, the beneficial effects of this utility model are:

[0011] 1. Based on the existing structure, the torsion bar spring and torque angle transmission device are eliminated, and the input shaft hand force end is replaced; instead, an angle sensor is installed on the steering screw, and the output steering stroke is controlled by collecting the angle angle rotated by the angle sensor.

[0012] 2. The positioning bearing provides rotational support for the positioning seat and will not affect the rotation of the steering screw. The positioning seat positions the upper end of the steering screw to ensure accurate installation. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model;

[0014] Figure 2 This is a schematic diagram of the worm gear and worm shaft mating structure of this utility model;

[0015] Figure 3 This is a schematic diagram of the overall appearance and structure of this utility model.

[0016] In the diagram: 1 Control motor, 2 Double row bearing, 3 Steering nut, 4 Steering screw, 5 Rocker arm, 6 Rocker arm shaft, 7 Angle sensor, 8 Adjusting shim, 9 Positioning seat, 10 Positioning center shaft, 11 Positioning bearing, 12 End cover, 13 Lower housing, 14 Bearing seat, 15 Upper housing, 16 Worm gear, 17 Worm. Detailed Implementation

[0017] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0018] Please see Figure 1-3This utility model provides a technical solution: a steer-by-wire actuator for commercial vehicles, comprising a lower housing 13, an upper housing 15, a steering screw 4, and an end cover 12. The lower housing 13 and the upper housing 15 are fixedly connected by screws, and together they form the actuator housing. The steering screw 4 is mounted in the lower housing 13 via a double-row bearing 2, and the upper end of the steering screw 4 is inserted into the upper housing 15. The upper end of the upper housing 15 is fixedly connected to the end cover 12 by screws. A positioning seat 9 is provided in the end cover 12, and the positioning seat 9 is mounted in the end cover 12 via a positioning bearing 11. The positioning bearing 11 provides rotational support for the positioning seat 9 and does not affect the rotation of the steering screw 4. A positioning center shaft 10 is provided at the center of the lower surface of the positioning seat 9. Shaft 10 is inserted into the center hole at the upper end of steering screw 4. This center hole is the hole for connecting steering screw 4 and torsion bar, and is a reserved hole for the original steering screw 4. In this patent, it is used as the center for positioning. An adjusting shim 8 is provided between positioning seat 9 and steering screw 4. The gap between positioning seat 9 and steering screw 4 can be adjusted by adjusting shim 8. This patent eliminates the torsion bar spring, torque angle transmitter and input shaft hand force end on the basis of the original structure. It is sealed by end cover 12 and positioned by positioning center shaft 10. Compared with traditional hydraulic steering, it saves accessories, such as power assist power source, pipeline, oil reservoir and other accessories. An angle sensor 7 is installed at the upper end of steering screw 4. The output steering stroke is controlled by collecting the rotation angle of angle sensor 7.

[0019] A worm gear 16 is provided in the upper housing 15. The worm gear 16 is mounted on the steering screw 4 and meshes with the worm 17. A control motor 1 is provided on the outside of the upper housing 15. The output shaft of the control motor 1 is connected to the worm 17. The vehicle electronic control unit sends a steering angle command to the motor controller of the control motor 1. The control motor 1 drives the worm 17 to rotate the steering screw 4 on the worm gear 16.

[0020] A steering nut 3 is provided on the steering screw 4. The steering nut 3 is connected to a rocker arm shaft 6. The other end of the rocker arm shaft 6 is connected to a rocker arm 5. The steering nut 3 on the steering screw 4 moves in a straight line, causing the rocker arm shaft 6 to rotate, which in turn causes the rocker arm 5 to swing.

[0021] The upper end of the lower housing 13 is provided with a bearing seat 14, and two double-row bearings 2 are provided. One double-row bearing 2 is installed at the bottom of the lower housing 13, and the other double-row bearing 2 is installed in the bearing seat 14. The double-row bearings 2 play a role in providing reliable and safe support for the steering screw 4.

[0022] The positioning seat 9 is designed with a convex structure. The circumference of the positioning seat 9 abuts against the inner ring of the positioning bearing 11. The positioning seat 9 plays the role of positioning the upper end of the steering screw 4 to ensure accurate installation.

[0023] Working principle: Based on the current structure, the torsion bar spring and torque angle transmission are eliminated, and the input shaft hand force end is replaced. An angle sensor 7 is directly installed on the steering screw 4. The vehicle electronic control unit sends the steering angle command to the motor controller of the control motor 1. The control motor 1 drives the worm 17 to rotate the steering screw 4 on the worm wheel 16. The steering nut 3 on the steering screw 4 moves linearly, which drives the rocker arm shaft 6 to rotate, and then drives the rocker arm 5 to swing. The steering stroke is controlled by collecting the rotation angle of the angle sensor 7.

[0024] The foregoing has shown and described the basic principles, main features and advantages of this utility model. Various changes and modifications may be made to this utility model without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of this utility model as claimed.

Claims

1. A steer-by-wire actuator for commercial vehicles, comprising a lower housing (13), an upper housing (15), a steering screw (4), and an end cap (12), characterized in that: The lower housing (13) and the upper housing (15) are fixedly connected by screws. The steering screw (4) is installed in the lower housing (13) through a double row bearing (2), and the upper end of the steering screw (4) is inserted into the upper housing (15). The upper end of the upper housing (15) is fixedly connected to the end cover (12) by screws. A positioning seat (9) is provided in the end cover (12). The positioning seat (9) is installed in the end cover (12) through a positioning bearing (11). A positioning center shaft (10) is provided at the center of the lower surface of the positioning seat (9). The positioning center shaft (10) is inserted into the center hole at the upper end of the steering screw (4). An adjusting shim (8) is provided between the positioning seat (9) and the steering screw (4). An angle sensor (7) is installed at the upper end of the steering screw (4).

2. The commercial vehicle steer-by-wire actuator according to claim 1, characterized in that: A worm gear (16) is provided in the upper housing (15). The worm gear (16) is mounted on the steering screw (4). The worm gear (16) meshes with the worm (17). A control motor (1) is provided on the outside of the upper housing (15). The output shaft of the control motor (1) is connected to the worm (17).

3. A steer-by-wire actuator for commercial vehicles according to claim 2, characterized in that: A steering nut (3) is provided on the steering screw (4), and a rocker arm shaft (6) is connected to the steering nut (3). The other end of the rocker arm shaft (6) is connected to a rocker arm (5).

4. A steer-by-wire actuator for commercial vehicles according to claim 1, characterized in that: The upper end of the lower housing (13) is provided with a bearing seat (14) and two double row bearings (2) are provided. One double row bearing (2) is installed at the bottom of the lower housing (13) and the other double row bearing (2) is installed in the bearing seat (14).

5. A steer-by-wire actuator for commercial vehicles according to claim 1, characterized in that: The positioning seat (9) is configured as a convex structure, and the circumferential direction of the positioning seat (9) abuts against the inner ring of the positioning bearing (11).

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