Electro-hydraulic recirculating ball steering gear of commercial vehicle

Abstract

The utility model discloses an electro-hydraulic recirculating ball steering gear of a commercial vehicle, which comprises a motor and controller assembly, a speed reducing mechanism assembly and a hydraulic recirculating ball steering gear, the output end of the motor and controller assembly is connected with the speed reducing mechanism assembly, and the speed reducing mechanism assembly comprises an input shaft and a worm and gear mechanism. The input shaft is connected with a worm and gear mechanism through a torsion bar spline, the worm and gear mechanism is connected with a hydraulic circulating ball steering gear through a cross shaft, and the output end of the hydraulic circulating ball steering gear is connected with a rocker arm shaft. According to the electro-hydraulic recirculating ball steering gear of the commercial vehicle, the output end of the speed reducing mechanism assembly is connected with the hydraulic recirculating ball steering gear through the cross shaft, and the connecting mode is simple in structure, low in machining cost, easy and convenient to install, high in strength and capable of bearing large loads. Meanwhile, the advantages of a hydraulic steering gear and an electric steering gear are combined, and the problems that when the input torque is too large, the cambered surface making contact with balls in the hydraulic steering gear deforms, and consequently jamming and steering failure are caused can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle engineering, in particular to an electro-hydraulic recirculating ball steering gear for commercial vehicles. Background Technique

[0002] The function of the steering gear is to appropriately transform the steering torque and steering angle from the steering wheel (mainly to reduce speed and increase torque), and then output them to the steering tie rod mechanism, so as to steer the vehicle. There are various types of steering gears, such as rack and pinion type, recirculating ball type, worm crank finger pin type, etc. Due to its own weight and technical requirements, commercial vehicles need a more stable and durable steering system. The recirculating ball steering gear has become the most suitable and widely used structure on commercial vehicles due to its structural characteristics and excellent performance.

[0003] The electric power-assisted deceleration mechanism assembly of the existing electro-hydraulic recirculating ball steering gear is generally of the worm and worm gear deceleration and assistance form. Referring to a smart recirculating ball steering gear assembly with safety redundancy disclosed in Chinese Patent Application CN117262004A, the input shaft B of the double-loop recirculating ball steering gear unit in this patent is connected to the worm shaft in the electric steering unit through a spline connection. Spline connection requires cutting spline grooves and manufacturing mating splines on parts, which is relatively complex in processing, has a high manufacturing cost, and requires precise fitting. The installation and disassembly processes are relatively complex and require special tools, increasing the difficulty and cost of maintenance. Content of the Utility Model

[0004] The utility model provides an electro-hydraulic recirculating ball steering gear for commercial vehicles, aiming to solve the problems in the existing electro-hydraulic recirculating ball steering gear, such as the input shaft of the recirculating ball steering gear unit is connected to the worm shaft in the electric steering unit through a spline connection, which is relatively complex in processing, has a high manufacturing cost, and the installation and disassembly processes are relatively complex and require special tools, increasing the difficulty and cost of maintenance.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] An electro-hydraulic recirculating ball steering gear for commercial vehicles includes a motor and controller assembly, a deceleration mechanism assembly, and a hydraulic recirculating ball steering gear. The output end of the motor and controller assembly is connected to the deceleration mechanism assembly. The deceleration mechanism assembly includes an input shaft and a worm and worm gear mechanism. The input shaft is connected to the worm and worm gear mechanism through a torsion bar spline. The worm and worm gear mechanism is connected to the hydraulic recirculating ball steering gear through a cross shaft. The output end of the hydraulic recirculating ball steering gear is connected to a rocker shaft. When there is a steering input for the commercial vehicle, the motor and controller assembly are connected to the deceleration mechanism assembly to transmit torque. The deceleration mechanism assembly is connected to the hydraulic recirculating ball steering gear, and the hydraulic recirculating ball steering gear is connected to the rocker shaft to output torque.

[0007] Further, the above-mentioned motor and controller assembly includes a motor, a drive board, and a controller. The motor is a six-phase motor, and the six-phase motor structure includes two sets of three-phase windings. There are two sets of drive boards, and the controller includes two independent control chips. Each control chip is connected to a set of drive boards, and each set of drive boards is respectively connected to a set of three-phase windings.

[0008] Further, the above-mentioned motor is an 8.5 Nm motor.

[0009] Further, a sensor is provided at the input end of the above-mentioned reduction mechanism assembly, and the sensor is fixed on a bearing housing assembly.

[0010] Further, the above-mentioned bearing housing assembly includes a bearing housing, and a column for fixing the sensor is provided on the bearing housing.

[0011] Further, the above-mentioned sensor is a torque angle sensor.

[0012] From the above description of the structure of the present invention, the present invention has the following advantages:

[0013] 1. For the electro-hydraulic recirculating ball steering gear of the present invention, the output end of the reduction mechanism assembly is connected to the hydraulic recirculating ball steering gear using a cross shaft. This connection method has a simple structure, low processing cost, easy installation, high strength, and can bear a large load. At the same time, it combines the advantages of hydraulic steering gears and electric steering gears, and can prevent the problem of jamming and inability to steer caused by the deformation of the arc surface in contact with the balls in the hydraulic steering gear when the input torque is too large.

[0014] 2. The motor uses a six-phase motor, the controller uses dual chips, and the drive board uses dual drive boards, with electronic redundancy backup and an emergency steering function. It can complete steering under various extreme conditions. One drive board is connected to one control chip and a set of three-phase windings in the motor structure, forming two independent control units. When any node in the controller chip of one set of electronic control units or on one of the drive boards fails, the other set of normal electronic control units will take over the entire control system and independently complete the control work of the steering assist. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the front view of the present invention.

[0016] Figure 2 It is the sectional view of the present invention.

[0017] Figure 3 It is the structural block diagram of the motor and controller assembly of the present invention.

[0018] Figure 4This is the structural diagram of the worm and worm gear mechanism of the present utility model.

[0019] Figure 5 This is the schematic structural diagram of the bearing block assembly of the present utility model.

[0020] Figure 6 This is the schematic structural diagram of the bearing block of the present utility model.

[0021] Figure 7 This is the structural configuration diagram of the transmission structure of the present utility model.

[0022] In the figure: 1, torsion bar; 2, worm gear; 3, worm gear shaft; 4, cross shaft; 5, cylindrical pin; 6, worm; 7, worm coupling; 8, bearing; 9, oil seal; 10, bearing block; 101, column; 11, sensor; 12, lock nut; 13, lock plug; 14, worm gear lock nut; 15, shaft snap ring; 16, hole snap ring; 17, upper cover; 20, motor and controller assembly; 21, motor; 211, three-phase winding; 22, drive plate; 23, controller; 231, control chip; 24, electronic control unit; 30, reduction mechanism assembly; 31, input shaft; 32, worm and worm gear mechanism; 40, hydraulic recirculating ball steering gear. Detailed implementation manners

[0023] The following describes the detailed implementation manners of the present utility model with reference to the accompanying drawings. To fully understand the present utility model, many details are described below. However, for those skilled in the art, the present utility model can be implemented without these details. For well-known components, methods and processes, they will not be described in detail below.

[0024] A commercial vehicle electro-hydraulic recirculating ball steering gear, referring to Figure 1 and Figure 2 , includes a motor and controller assembly 20, a reduction mechanism assembly 30 and a hydraulic recirculating ball steering gear 40. The output end of the motor and controller assembly 20 is connected to the reduction mechanism assembly 30. The reduction mechanism assembly 30 includes an input shaft 31 and a worm and worm gear mechanism 32. The input shaft 31 is connected to the worm and worm gear mechanism 32 through a torsion bar spline. The worm and worm gear mechanism 32 is connected to the hydraulic recirculating ball steering gear 40 through a cross shaft 4. The output end of the hydraulic recirculating ball steering gear 40 is connected to a rocker arm shaft.

[0025] Referring to Figure 3The motor and controller assembly 20 includes a motor 21, a drive board 22 and a controller 23. The motor 21 adopts an 8.5Nm six-way motor. The six-way motor structure includes two groups of three-phase windings 211. There are two groups of drive boards 22. The controller 23 includes two independent control chips 231. There is electronic redundant backup. Each control chip 231 is connected to a group of drive boards 22, and each group of drive boards 22 is respectively connected to a group of three-phase windings 211. A group of three-phase windings 211 is connected to a group of drive boards 22 and a control chip 231 to form an electronic control unit 24.

[0026] Reference Figure 3 When the motor and controller assembly 20 is normal, the two electronic control units 24 work together, each taking half of the torque output, and jointly controlling the commercial vehicle to complete the steering. At the same time, there is signal communication between the two control chips 231 of the controller 23. When the control chip of one of the electronic control units or any node on one of the drive boards fails, the other normal electronic control unit will take over the entire control system, and the normal electronic control unit will independently complete the control of the steering power.

[0027] Reference Figure 1 and Figure 4 The speed reduction mechanism assembly 30 includes an input shaft 31 and a worm gear mechanism 32. The worm gear mechanism 32 includes a worm shaft torsion bar assembly, a worm assembly, an upper cover assembly, a bearing seat assembly, a sensor unit assembly, and a speed reduction mechanism housing assembly.

[0028] Reference Figure 1 The worm wheel 2 is sleeved on the worm wheel shaft 3. The outer ring of the worm wheel 2 is made of PA66 nylon material, and the inner ring is made of 45 steel. A torsion bar 1 and a sliding bearing are pressed on the front end of the worm wheel shaft 3. An O-ring is installed on the torsion bar 1. The input shaft 31 is connected to the torsion bar 1. A hole is punched at the connection, and a cylindrical pin 5 is installed in the hole to form a worm wheel shaft torsion bar assembly.

[0029] Reference Figure 1 and Figure 4 A worm coupling 7 is provided at the top of the worm 6, and a bearing 8 is installed at the bottom of the worm coupling 7 to form a worm assembly; the motor and controller assembly 20 is connected to the worm 26 through the worm coupling 7 and the elastomer, and is fixed with bolts, and the wiring harness of the controller and the sensor is connected.

[0030] Reference Figure 1 , Figure 5 and Figure 6, the bearing 8, oil seal 9 and O-ring are pressed into the upper cover 17 to form the upper cover assembly. The bearing 8 and O-ring are pressed into the bearing seat 10 to form the bearing seat assembly. An asymmetric column 101 is provided on the bearing seat 10 to fix the sensor 11 and position the initial zero position of the sensor 11. The bearing seat assembly is installed into the input shaft and the torsion bar assembly of the worm shaft. The sensor 11 is welded to the worm shaft 3 to form the sensor unit assembly. The sensor 11 is a (4 + 2) type torque angle sensor.

[0031] The bearing 8 is pressed into the corresponding position of the reduction gear housing and the hole retaining ring 16 is installed to form the reduction gear housing assembly.

[0032] Lubricating grease is applied to the worm 2 and the worm gear 6. Then, the sensor unit assembly, the worm assembly, the reduction gear housing assembly, and the input shaft and the torsion bar assembly of the worm shaft are assembled together. The positions of the worm 2 and the worm gear 6 are adjusted and fixed through the lock nut 12, lock plug 13, worm gear lock nut 14, and shaft retaining ring 15. Among them, the worm gear lock nut 14 and the shaft retaining ring 15 are used to fix the bearing 8, and the lock plug 13 and the lock nut 12 are used to ensure the correct installation position of the worm 6. Then, the worm 2 and the worm gear 6 are run-in, the sensor wiring harness is installed, and the upper cover assembly is installed into the reduction gear housing assembly to form the reduction gear assembly 30.

[0033] Refer to Figure 1 and Figure 7 , when the commercial vehicle has a steering input, the torque and relative angle feedback signals generated by the deformation of the input shaft 31 and the torsion bar 1 are sent to the controller 23. The controller 23 controls the motor 21 to output electric torque and connects to the reduction gear assembly 30 to transmit the torque. The reduction gear assembly 30 is connected to the hydraulic recirculating ball steering gear 40. The hydraulic recirculating ball steering gear 40 is connected to the rocker arm shaft to output torque to complete the steering. The hydraulic recirculating ball steering gear 40 also controls the oil pressure output torque through the signal feedback of the torque and relative angle generated by the deformation of the torsion bar 1 by the controller 23. The performance matching between the two systems is controlled by software, and they work together to complete the steering command.

[0034] The structure of the present utility model is simple and can be applied to most commercial vehicle models such as large buses and heavy trucks.

[0035] The above is only the specific implementation manner of the present utility model, but the design concept of the present utility model is not limited thereto. Any non-substantive modification made to the present utility model using this concept shall fall within the scope of infringement of the protection of the present utility model.

Claims

1. A commercial vehicle electro-hydraulic circulating ball steering gear, characterized in that: The invention comprises a motor and controller assembly, a speed reduction mechanism assembly and a hydraulic circulating ball steering gear, wherein the output end of the motor and controller assembly is connected to the speed reduction mechanism assembly, the speed reduction mechanism assembly comprises an input shaft and a worm gear mechanism, the input shaft is connected to the worm gear mechanism through a torsion bar spline, the worm gear mechanism is connected to the hydraulic circulating ball steering gear through a cross shaft, and the output end of the hydraulic circulating ball steering gear is connected to a rocker shaft; when the commercial vehicle has a steering input, the motor and controller assembly is connected to the speed reduction mechanism assembly to transmit torque, the speed reduction mechanism assembly is connected to the hydraulic circulating ball steering gear, and the hydraulic circulating ball steering gear is connected to the output torque of the rocker shaft.

2. The commercial vehicle electro-hydraulic circulating ball steering gear according to claim 1, characterized in that: The motor and controller assembly includes a motor, a drive board and a controller. The motor is a six-way motor. The six-way motor structure includes two groups of three-phase windings. There are two groups of drive boards. The controller includes two independent control chips. Each control chip is connected to a group of drive boards, and each group of drive boards is respectively connected to a group of three-phase windings.

3. The commercial vehicle electro-hydraulic circulating ball steering gear according to claim 1, characterized in that: The motor is a 8.5Nm motor.

4. The commercial vehicle electro-hydraulic circulating ball steering gear according to claim 1, characterized in that: A sensor is provided at the input end of the speed reduction mechanism assembly, and the sensor is fixed on a bearing seat assembly.

5. The commercial vehicle electro-hydraulic circulating ball steering gear according to claim 4, characterized in that: The bearing seat assembly comprises a bearing seat, and a column for fixing the sensor is provided on the bearing seat.

6. The commercial vehicle electro-hydraulic circulating ball steering gear according to claim 4, characterized in that: The sensor is a torque angle sensor.

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