Commercial vehicle power-assisted steering device with large torque output

Abstract

The commercial vehicle power-assisted steering device with the large torque output comprises a steering gear body and a speed reducer, the steering gear body comprises a steering gear shell, a steering rocker arm shaft, a lead screw and a circulating ball assembly, the lead screw is installed in the steering gear shell, the circulating ball assembly acts on the lead screw, and the steering rocker arm shaft is connected with the circulating ball assembly. According to the commercial vehicle power-assisted steering device with the large torque output, the input large torque is reduced through the planetary gear with the large transmission ratio, steering assistance is directly provided through the motor, a power steering oil pump, a hose, hydraulic oil, a conveying belt and a belt pulley installed on an engine which are necessary for a hydraulic power steering system are omitted, energy is saved, and the power-assisted steering device is convenient to use. And the environment is protected. The steering device has great design flexibility, is compact in structure and small in size, is more suitable for commercial large-torque vehicles, fills the blank of an electric power steering gear, is green and efficient, and can improve the operation comfort of a driver in the driving process.

Description

Technical Field

[0001] The invention relates to the field of automobile power-driven steering gears, and in particular to a commercial vehicle power steering device with large torque output. Background Art

[0002] In the current automobile manufacturing industry, commercial vehicles are widely used in logistics, transportation and other fields due to their high load and high efficiency. However, with the increasingly stringent environmental regulations and the growing market demand for high-performance vehicles, the mainstream structure of commercial vehicles in my country is still a pure hydraulic circulating ball structure, lacking a steering gear that is better suited to commercial vehicles with high power consumption and greater steering assistance requirements. Summary of the invention

[0003] In order to solve the technical problems existing in the prior art, the present invention provides a commercial vehicle power steering device with large torque output.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] A commercial vehicle power steering device with large torque output comprises a steering gear body and a reducer. The steering gear body comprises a steering gear housing, a steering rocker arm shaft, a screw rod and a circulating ball assembly. The screw rod is installed in the steering gear housing. The circulating ball assembly acts on the screw rod. The steering rocker arm shaft is connected to the circulating ball assembly.

[0006] As a preferred technical solution, the steering gear housing includes an outer shell, a screw front box cover and a screw rear box cover, the outer shell and the screw front box cover are connected by bolts, and the outer shell and the screw rear box cover are connected by screws.

[0007] As a preferred technical solution, both ends of the screw rod are respectively sealed and connected to the screw rod front box cover and the screw rod rear box cover through oil seals.

[0008] As a preferred technical solution, the output end of the steering rocker arm shaft is positioned through the housing and connected to a Havers through bolts, and the sweeping teeth on the steering rocker arm shaft mesh with the rack on the circulating ball assembly.

[0009] As a preferred technical solution, the reducer includes a reducer housing, a rear cover, a locking ring, a drive unit, a planetary carrier, planetary gears on both sides, a first sun gear and a second sun gear. The reducer housing is threadedly connected to the rear cover and the connection is fixed by a locking ring. The steering gear housing is connected to the reducer housing by screws. The drive unit is connected to the planetary gears on both sides through the planetary carrier. The planetary gears are meshed with the first sun gear. The first sun gear is an integral part of the steering rocker arm shaft, and the second sun gear is connected to the rear cover by a spline.

[0010] As a preferred technical solution, the drive unit includes a drive motor and a coupling, the planetary carrier includes a double-headed worm and a turbine, the shaft of the drive motor is connected to the double-headed worm through a coupling to input torque, the turbine is meshed with the double-headed worm, and the double-headed worm transmits the torque to the planetary gears on both sides through the turbine.

[0011] As a preferred technical solution, the turbine is connected and positioned with the rear cover via a stepped shaft, and the rear cover is connected with the reducer housing via threads.

[0012] As a preferred technical solution, the steering gear also includes a torque sensor and an electronic control unit. The torque sensor detects the direction of the steering wheel and the size of the torque, and transmits a voltage signal to the electronic control unit. The electronic control unit controls the operation of the drive motor. After the reducer decelerates and increases the torque, the input torque is reduced through the planetary carrier.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) The high-torque power steering device for commercial vehicles of the present invention has the advantages of large transmission ratio, high output torque, low energy consumption, high reliability, etc. The high-performance electric power steering device will significantly improve the controllability and stability of commercial vehicles, reduce the risk of traffic accidents caused by steering system failures, and provide safer driving protection for drivers and passengers; the design of large transmission ratio and high output torque will enable commercial vehicles to maintain excellent steering performance under heavy load and high torque conditions, improve the transportation efficiency and economic benefits of the vehicle; the low-energy consumption design will help reduce the fuel consumption and emissions of commercial vehicles, meet the requirements of environmental protection regulations, and promote the development of green transportation.

[0015] (2) The commercial vehicle power steering device with large torque output of the present invention has the advantages of flexible layout and high transmission efficiency. The output of the motor is decelerated and torque-increased by the speed reduction mechanism, and then drives the worm gear mechanism to generate a large steering assist. Since the electric power steering device only needs electricity and does not use hydraulic pressure, many components are omitted compared with the mechanical hydraulic power steering device. There is no oil pump, oil pipe, pressure flow control valve, oil storage tank, etc. required by the hydraulic system. The number of parts is small, the layout is convenient, and the weight is light; and there is no "parasitic loss" and liquid leakage loss. Therefore, the electric power steering device can save energy by about 80% under various driving conditions, improve the running performance and fuel economy of the vehicle, and meet all aspects of the steering device of large vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a partial cross-sectional view of a commercial vehicle power steering device with a large torque output according to the present invention;

[0017] Figure 2 It is a partial cross-sectional view of a reducer in a commercial vehicle power steering device with a large torque output according to the present invention;

[0018] Figure 3 It is a front view of the internal structure of the commercial vehicle power steering device with large torque output of the present invention;

[0019] Figure 4 is a top view of a commercial vehicle power steering device with large torque output according to the present invention;

[0020] Figure 5 The invention discloses a schematic diagram of the motion of a reducer of a commercial vehicle power steering device with a large torque output.

[0021] In the figure: 1. Drive motor; 2. Screw; 3. Recirculating ball assembly; 4. Housing; 5. Steering rocker shaft; 6. Double-headed worm; 7. Turbine; 8. First planetary gear; 9. First sun gear; 10. Second sun gear; 11. Second planetary gear; 12. Haval; 13. Screw front box cover; 14. Screw rear box cover; 15. Reducer housing; 16. Stepped shaft; 17. Rear cover. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below in conjunction with specific implementation methods:

[0023] like Figure 1 As shown, a commercial vehicle power steering device with large torque output includes a steering gear body and a reducer. The steering gear body includes a steering gear housing, a steering rocker arm shaft 5, a screw rod 2 and a circulating ball assembly 3. The screw rod 2 is installed in the steering gear housing. The circulating ball assembly 3 acts on the screw rod 2. The steering rocker arm shaft 5 is connected to the circulating ball assembly 3.

[0024] The commercial vehicle power steering device with high torque output of the present invention systematically presents a set of relatively high-quality solutions, which reduces the input high torque through planetary gears with a large transmission ratio, and directly provides steering assistance by the motor, eliminating the power steering oil pump, hose, hydraulic oil, conveyor belt and pulley installed on the engine required by the hydraulic power steering system, saving energy and protecting the environment. The steering device in this solution has great design flexibility and a compact system structure and small size, which is more suitable for commercial high-torque vehicles, filling the gap in electric power steering in this area, and is green and efficient while also improving the comfort of the driver's operating feeling during driving.

[0025] The steering gear housing comprises an outer shell 4, a screw front box cover 13 and a screw rear box cover 14. The outer shell 4 is fixedly connected to the screw front box cover 13 by bolts and sealing gaskets, and the outer shell 4 is fixedly connected to the screw rear box cover 14 by sealing gaskets and screws.

[0026] The screw rod 2 is arranged in the housing 4. Figure 3As shown, the two ends of the screw rod 2 are respectively sealed and connected to the screw rod front box cover 13 and the screw rod rear box cover 14 through oil seals.

[0027] The output end of the steering rocker arm shaft 5 is positioned by the housing 4 and sealed with a sealing gasket. The steering rocker arm shaft 5 passes through the housing 4 and is connected to a Haver 12 by bolts. The sweeping teeth on the steering rocker arm shaft 5 are meshed with the rack on the circulating ball assembly 3.

[0028] The reducer includes a reducer housing 15, a rear cover 17, a locking ring, a drive unit, a planet carrier, planetary gears 8 and 11 on both sides, a first sun gear 9 and a second sun gear 10. Figure 4 As shown, the reducer housing 15 is threadedly connected to the rear cover 17 and the connection is fixed by a locking ring, and the steering gear housing is connected to the reducer housing 15 by screws, as shown in FIG. Figure 2 As shown, the drive unit is connected to the planetary gears 8 and 11 on both sides through the planet carrier, the planetary gears 8 and 11 are meshed with the first sun gear 9, the first sun gear 9 and the steering rocker arm shaft 5 are integrated, and the second sun gear 10 is connected to the rear cover 17 through a spline.

[0029] The drive unit includes a drive motor 1 and a coupling, and the planet carrier includes a double-headed worm 6 and a turbine 7. The shaft of the drive motor 1 is connected to the double-headed worm 6 through the coupling to transmit the input torque. The turbine 7 is meshed with the double-headed worm 6. The double-headed worm 6 transmits the torque to the planetary gears 8 and 11 on both sides through the turbine 7, and then the planetary gears 8 and 11 transmit the torque to the first sun gear 9 to output the torque. The turbine 7 is connected and positioned with the rear cover 17 through the stepped shaft 16, and the rear cover 17 is connected to the reducer housing 15 through threads. The turbine 7 is connected and positioned with the rear cover 17 through the stepped shaft 16, and the rear cover 17 is connected to the reducer housing 15 through threads.

[0030] like Figure 5 As shown, the reducer adopts a planetary reducer with a worm gear as a planet carrier, and a turbine 7 is used as the input of the planetary reducer. The reducer adopts a relatively large transmission ratio, and the double-headed worm 6 uses the turbine 7 as a planet carrier, and uses the planet carrier as input to transmit the torque to the planetary gears 8 and 11 on both sides. The double-headed worm 6 drives the turbine 7 to rotate, and the second sun gear 10 is used as the output. The double-headed worm 6 is connected to the drive motor 1, and uses electrical energy to sense the driver's steering intention and generate corresponding electrical signals to control the working state of the steering valve and the drive motor 1, thereby realizing the control of the vehicle steering.

[0031] The steering gear also includes a torque sensor and an electronic control unit. The torque sensor is installed on the shaft of the steering wheel. When the driver manipulates the steering wheel to steer, the torque sensor detects the steering direction of the steering wheel and the size of the torque, and transmits the voltage signal to the electronic control unit. The electronic control unit sends instructions to the motor controller based on the torque voltage signal, rotation direction and vehicle speed signal detected by the torque sensor, so that the drive motor 1 outputs a steering assist torque of corresponding size and direction, thereby generating auxiliary power. When the car is not turning, the electronic control unit does not send instructions to the motor controller, and the drive motor 1 does not work. That is, the electronic control unit determines the rotation direction and optimal assist torque of the drive motor 1 according to the signals output by each sensor, sends a control signal to the drive motor 1 and the clutch, and controls the rotation of the DC motor through power drive. After the output of the drive motor 1 is decelerated and torque-increased by the deceleration mechanism, a two-stage planetary reducer with a larger transmission ratio is used, and a worm gear transmission is used to reduce the input large torque. At the same time, on the basis of adopting a circulating ball structure, the transmission efficiency of the transmission system is increased.

[0032] This embodiment is only a further explanation of the invention rather than a limitation of the invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as they are within the scope of the claims of the invention, they are protected by the patent law.

Claims

1. A commercial vehicle power steering device with large torque output, characterized in that: It includes a steering gear body and a reducer. The steering gear body includes a steering gear housing, a steering rocker arm shaft, a screw rod and a circulating ball assembly. The screw rod is installed in the steering gear housing. The circulating ball assembly acts on the screw rod. The steering rocker arm shaft is connected to the circulating ball assembly.

2. The commercial vehicle power steering device with large torque output according to claim 1, characterized in that: The steering gear housing comprises an outer shell, a screw rod front box cover and a screw rod rear box cover. The outer shell is connected to the screw rod front box cover by bolts, and the outer shell is connected to the screw rod rear box cover by screws.

3. The commercial vehicle power steering device with large torque output according to claim 2, characterized in that: The two ends of the screw rod are respectively connected to the screw rod front box cover and the screw rod rear box cover through oil seals.

4. The commercial vehicle power steering device with large torque output according to claim 2, characterized in that: The output end of the steering rocker arm shaft is positioned through the housing and connected to a Havers through bolts, and the sweeping teeth on the steering rocker arm shaft are meshed with the rack on the circulating ball assembly.

5. The commercial vehicle power steering device with large torque output according to claim 1, characterized in that: The reducer includes a reducer housing, a rear cover, a locking ring, a drive unit, a planetary carrier, planetary gears on both sides, a first sun gear and a second sun gear. The reducer housing is threadedly connected to the rear cover and the connection is fixed by a locking ring. The steering gear housing is connected to the reducer housing by screws. The drive unit is transmission-connected to the planetary gears on both sides through the planetary carrier. The planetary gears are meshed with the first sun gear. The first sun gear is an integral part of the steering rocker arm shaft. The second sun gear is connected to the rear cover by a spline.

6. The commercial vehicle power steering device with large torque output according to claim 5, characterized in that: The drive unit includes a drive motor and a coupling, the planetary carrier includes a double-headed worm and a turbine, the shaft of the drive motor is connected to the double-headed worm through the coupling to input torque, the turbine is meshed with the double-headed worm, and the double-headed worm transmits torque to the planetary gears on both sides through the turbine.

7. The commercial vehicle power steering device with large torque output according to claim 6, characterized in that: The turbine is connected and positioned with the rear cover through a stepped shaft, and the rear cover is connected with the reducer housing through threads.

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