Power-assisted steering system and commercial vehicle

Abstract

The invention provides a power-assisted steering system and a commercial vehicle, and relates to the technical field of vehicles, the power-assisted steering system comprises a steering column, a steering gear and a whole vehicle controller, the steering gear comprises an input shaft, a main shell, a steering gear controller, a power assisting device and a rack, and the steering column is connected with the input shaft; the input shaft is rotationally connected with the main shell and provided with a first sensor, the first sensor is used for detecting parameter information in the rotating process of the input shaft and converting the parameter information into a first electric signal, and the vehicle control unit is used for generating a power-assisted curve according to the first electric signal, a vehicle speed signal and a vehicle starting signal and converting the power-assisted curve into a curve signal. The steering gear controller is in signal connection with the power assisting device, the steering gear controller is used for adjusting the output assisting power of the power assisting device according to the curve signal, and the power assisting device comprises a worm and gear reducing mechanism; the input shaft and the worm and gear reducing mechanism are both in transmission fit with the rack. The power-assisted steering system has the advantages of being high in transmission efficiency, good in noise, vibration and sound vibration roughness performance, better in driving control feeling and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a power steering system and a commercial vehicle. Background Art

[0002] Most commercial vehicles currently use hydraulic power steering, which has the disadvantages of low transmission efficiency, poor noise, vibration and acoustic roughness performance, etc., and the steering control force is heavy and the feel is poor, the highway feel is poor, and the driving experience is not good, which cannot meet the development trend of new energy vehicles.

[0003] Therefore, there is an urgent need to provide a power steering system and a commercial vehicle that can solve at least one of the above technical problems. Summary of the invention

[0004] The object of the present invention is to provide a power steering system and a commercial vehicle, which have the advantages of high transmission efficiency, good noise, vibration and harshness performance, better driving control feeling, etc.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a power steering system, comprising a steering column, a steering gear and a vehicle controller, wherein the steering gear comprises an input shaft, a main housing, a steering gear controller, a power assist device and a rack, and the steering column is connected to the input shaft;

[0007] The input shaft is rotationally connected to the main housing and is provided with a first sensor, the first sensor is used to detect parameter information of the input shaft rotation process and convert it into a first electrical signal, the first sensor and the steering gear controller are both signal-connected to the vehicle controller, the vehicle controller is used to generate a power-assistance curve according to the first electrical signal, a vehicle speed signal and a vehicle start signal and convert it into a curve signal, the steering gear controller is signal-connected to the power-assist device, the steering gear controller is used to adjust the magnitude of the power-assistance output by the power-assist device according to the curve signal, and the power-assist device includes a worm gear reduction mechanism;

[0008] The input shaft and the worm gear reduction mechanism are both matched with the rack transmission.

[0009] Furthermore, the steering column comprises an upper column, a lower column and a stopper, the upper column is slidably matched with the lower column along the extension direction of the lower column, and a clamping structure for increasing friction is provided between the upper column and the lower column;

[0010] The stopper is connected to the upper tubular column, and the stopper is configured to limit the position of the upper tubular column when the pressure between the upper tubular column and the lower tubular column is less than a first threshold value and to loosen from the upper tubular column when the pressure between the upper tubular column and the lower tubular column is greater than the first threshold value.

[0011] Furthermore, the limiter is used to be installed on the vehicle frame, and the power steering system further includes a second sensor and a limiter controller, and the second sensor and the limiter are both connected to the limiter controller by signal;

[0012] The second sensor is used to detect the impact force on the steering wheel and convert it into a force signal, and the limit member controller is used to receive the force signal and control the limit member to loosen from the frame when the impact force is greater than a second threshold.

[0013] Furthermore, the second threshold is equal to the first threshold.

[0014] Furthermore, the upper pipe column is sleeved on the outside of the lower pipe column, and the clamping structure includes a plurality of protrusions protruding from the inner wall of the upper pipe column to the outer wall of the lower pipe column.

[0015] Furthermore, the upper pipe column includes a pipe body, a mounting bracket and an adjusting member, the mounting bracket is connected to the limiting member, the adjusting member is connected between the mounting bracket and the pipe body, and the adjusting member is used to adjust and lock the installation angle of the pipe body relative to the mounting bracket.

[0016] Furthermore, the steering column also includes an intermediate shaft, a first universal joint, a second universal joint and an output shaft, one end of the intermediate shaft is rotatably connected to an end of the lower column away from the upper column through the first universal joint, the other end of the intermediate shaft is rotatably connected to the output shaft through the second universal joint, and the output shaft is connected to the input shaft.

[0017] Further, the first universal joint and the second universal joint each include a first joint, a second joint and a connecting frame, the first joint is rotatably matched with the connecting frame around a first direction and the rotation angle is greater than 40°, the second joint is rotatably matched with the connecting frame around a second direction and the rotation angle is greater than 40°, and the second direction is perpendicular to the first direction.

[0018] Furthermore, the power assist device also includes a motor, which is signal-connected to the steering gear controller, and the motor cooperates with the rack transmission through the worm gear reduction mechanism.

[0019] In a second aspect, the present invention further provides a commercial vehicle, comprising the power steering system described in the above solution.

[0020] The power steering system and commercial vehicle provided by the present invention can produce the following beneficial effects:

[0021] Compared with the prior art, the power steering system provided in the first aspect of the present invention has a power assist device with a worm gear reduction mechanism, and the power is output to the rack after being reduced in speed. The steering system has high transmission efficiency, low energy loss, more energy saving, good noise, vibration and acoustic roughness performance, and a good vehicle driving environment. The power assist device can provide reverse assistance during driving, and has good road feel feedback, which can bring a better driving control feel and meet the development trend of new energy vehicles.

[0022] The commercial vehicle provided in the second aspect of the present invention has the power steering system provided in the first aspect of the present invention, thereby having all the beneficial effects of the power steering system provided in the first aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of a three-dimensional structure of a power steering system provided by an embodiment of the first aspect of the present invention;

[0025] Figure 2 A schematic diagram of a three-dimensional structure of a steering gear (without a main housing) provided for an embodiment of the first aspect of the present invention;

[0026] Figure 3 A side view of a steering column in a first state provided by an embodiment of the first aspect of the present invention;

[0027] Figure 4 A schematic diagram of a three-dimensional structure of a steering column in a second state provided by an embodiment of the first aspect of the present invention Figure 1 ;

[0028] Figure 5 for Figure 4 A local enlarged schematic diagram of point A;

[0029] Figure 6 A schematic diagram of a three-dimensional structure of a steering column in a second state provided by an embodiment of the first aspect of the present invention Figure 2 ;

[0030] Figure 7 for Figure 6 A partial enlarged schematic diagram of point B.

[0031] Icons: 1-steering column; 11-upper column; 111-tube body; 1111-protrusion; 112-mounting bracket; 1121-clamping part; 113-adjusting member; 1131-connecting shaft; 1132-bracket; 1133-handle; 12-lower column; 13-limiting member; 131-limiting block; 132-limiting strip; 14-intermediate shaft; 141-upper intermediate shaft; 142-lower intermediate shaft; 15-first universal joint; 151-first joint; 152-second joint; 153-connecting frame; 16-second universal joint; 17-output shaft; 18-frame; 2-steering gear; 21-input shaft; 22-main housing; 23-steering gear controller; 24-power assist device; 241-worm gear reduction mechanism; 242-motor; 25-rack; 26-pull rod. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0036] The embodiment of the first aspect of the present invention is to provide a power steering system, such as Figure 1 and Figure 2 As shown, it includes a steering column 1, a steering gear 2 and a vehicle controller, the steering gear 2 includes an input shaft 21, a main housing 22, a steering gear controller 23, a power assist device 24 and a rack 25, and the steering column 1 is connected to the input shaft 21;

[0037] The input shaft 21 is rotatably connected to the main housing 22 and is provided with a first sensor, the first sensor is used to detect parameter information of the rotation process of the input shaft 21 and convert it into a first electrical signal, the first sensor and the steering gear controller 23 are both connected to the vehicle controller signal, the vehicle controller is used to generate a power-assistance curve according to the first electrical signal, the vehicle speed signal and the vehicle start signal and convert it into a curve signal, the steering gear controller 23 is connected to the power-assistance device 24 signal, the steering gear controller 23 is used to adjust the magnitude of the power-assistance output by the power-assistance device 24 according to the curve signal, and the power-assistance device 24 includes a worm gear reduction mechanism 241;

[0038] The input shaft 21 and the worm gear reduction mechanism 241 are both in driving cooperation with the rack 25 .

[0039] When the steering system provided by the above embodiment is in use, the driver turns the steering wheel and the steering column 1 drives the input shaft 21 to rotate relative to the main housing 22. Since the input shaft 21 and the rack 25 cooperate in transmission, the rack 25 can be moved. At the same time, the vehicle controller can generate a power assist curve according to the vehicle speed signal, the vehicle start signal and the first electrical signal emitted by the first sensor and convert it into a curve signal. The steering gear controller 23 can adjust the size of the power assist output by the power assist device 24 according to the curve signal, thereby realizing that the power steering system provides appropriate steering assistance through the power assist device 24 according to the driving scenario, which is more energy-efficient and has better response than traditional hydraulic systems.

[0040] Among them, the vehicle speed signal can be generated by a sensor that detects the vehicle speed, and the vehicle controller can receive the above vehicle speed signal. When the vehicle controller receives the vehicle start signal, it forms a power assistance curve as the first electrical signal and the vehicle speed signal change.

[0041] In addition, the parameter information of the rotation process of the input shaft 21 may include at least one of the rotation angle information and torque information of the input shaft 21 .

[0042] The power-assisted device 24 in the above-mentioned power-assisted steering system has a worm gear reduction mechanism 241, which amplifies the torque through the reduction mechanism and effectively and accurately transmits the power assistance to the rack 25, so that the steering system has high transmission efficiency, small energy loss, more energy saving, good noise, vibration and acoustic roughness performance, and a good driving environment for the whole vehicle. When driving, the power-assisted device 24 can provide reverse assistance, with good road feel feedback, which can bring a better driving control feel.

[0043] In the above embodiment, the first sensor is integrated with the steering gear 2 to replace the angle sensor in the traditional electro-hydraulic power-assist structure. The signal transmission efficiency is faster, the steering response is quicker, and the space utilization rate of the steering column 1 is higher, which can achieve cost reduction for each vehicle.

[0044] In an optional implementation, the model of the first sensor may be TAS011061-71.

[0045] In an alternative embodiment, if Figure 2 As shown, the power assist device 24 also includes a motor 242, which is connected to the steering gear controller 23 by signal. The steering gear controller 23 can adjust the magnitude of the power assist output by the motor 242 according to the curve signal. The motor 242 transmits power to the rack 25 through the worm gear reduction mechanism 241, so that the rack 25 moves left and right. Pull rods 26 are connected to both ends of the rack 25, and the ends of the pull rods 26 can be connected to the wheels. Under the drag of the rack 25, the pull rods 26 realize the left and right turning of the wheels and assist the rotation of the wheels.

[0046] The above configuration enables the power assist device 24 to realize multiple functions. For example, the power assist device 24 can have a speed-dependent power assist function. When driving at low speed or parking, the power assist device 24 provides a large power assist to make steering easier and reduce the driver's physical exertion. When the vehicle is driving at high speed, the system automatically reduces the power assist force to increase the stability of the steering wheel and ensure the stability and safety of high-speed driving. For another example, the power assist device 24 can have a return control function to assist the vehicle to automatically return to the center after turning. The steering controller 23 helps the vehicle maintain a straight driving state by controlling the size and direction of the power assist of the motor 242, thereby improving the convenience of driving. For another example, the power assist device 24 can have a damping control function. When driving on an uneven road, the power assist device 24 can provide an appropriate damping force to suppress the shaking of the steering wheel caused by the vibration of the road surface and improve the driving smoothness. For another example, the power assist device 24 can have a road vibration suppression function. The reverse torque of the motor 242 offsets the vibration caused by the uneven road surface, reduces the vibration transmitted to the steering wheel, and improves the driving comfort. For another example, the power assist device 24 may have an inertia and friction compensation function. In view of the internal friction and inertia of the steering system, the steering gear controller may adjust the power assist output of the power assist device 24 to ensure the linearity and consistency of the steering response.

[0047] The amount of assistance required for each function can be calculated using the following data.

[0048] Set the basic assist torque required to be T_assist:

[0049] T_assist=K_assist(v)·T_driver;

[0050] Set the assist torque required for active return to T_return:

[0051] T_return=K_return(θ,ω,v)·T_Δθ;

[0052] Set the assist torque required for damping compensation to T_damp:

[0053] T_damp=K_damp(v,ω)·ω;

[0054] Set the assist torque required for friction compensation to T_friction:

[0055] T_friction=K_friction·sign(ω);

[0056] Set the assist torque required for inertia compensation to T_inertia:

[0057] T_inertia=K_inertia·dω / dt;

[0058] The assist torque required for the output torque of the motor 242 is set to T_motor:

[0059] T_motor=T_assist+T_return+T_damp+T_friction+T_inertia.

[0060] Where: K_assist(v) is the assist gain coefficient with vehicle speed;

[0061] K_return (θ, ω, v) is the return gain coefficient with angle, angular velocity and vehicle speed;

[0062] K_damp(v,ω) is the damping gain coefficient with vehicle speed and angular velocity;

[0063] K_friction is the friction gain coefficient;

[0064] K_inertia is the inertia gain coefficient;

[0065] T_driver is the driver's input hand torque;

[0066] T_Δθ is the self-aligning torque based on the difference between the target angle and the current angle;

[0067] ω is the angular velocity of the motor 242;

[0068] sign(ω) is the sign function of the angular velocity of the motor 242. The sign function is also called the symbol function. Its function is to take the sign (positive or negative) of a number. The basic definition of the sign function is: if the parameter is greater than 0, return 1; if the parameter is less than 0, return -1; if the parameter is equal to 0, return 0;

[0069] dω / dt is the rate of change of the angular velocity of the motor 242 with time.

[0070] The above-mentioned power steering system can use the controller area network to achieve precise communication and coordinated control with other key systems in the car.

[0071] Specifically, the steering controller 23 can be connected to the vehicle engine controller, braking system, body control module and other signals through the controller area network to exchange key performance parameters (such as vehicle speed, wheel angle, vehicle status) to control the power assist device 24 in real time to adjust the steering assist to ensure steering accuracy and vehicle stability.

[0072] Data sharing and command execution between the steering controller 23 and other systems are realized through the controller area network, ensuring seamless cooperation and response between systems. This integrated control mechanism enhances the driving safety and operating comfort of the vehicle.

[0073] Of course, in other embodiments, the steering gear controller 23 and the vehicle controller can also cooperate with each other to realize advanced functions such as lane departure, lane departure warning, automatic parking, etc., to improve driving safety and convenience. The steering gear controller 23 can also monitor vehicle performance and diagnose potential faults in real time, automatically record fault codes, and quickly locate problems, thereby simplifying the maintenance process and reducing maintenance time.

[0074] In an optional embodiment, the steering gear controller 23 may include a main chip, an auxiliary chip, a storage chip, a driver chip, a CAN (Controller Area Network) transceiver, and a motor position chip, etc., which are signal-connected to each other. Among them, the model of the main chip may be SPC560P50L3CEFAY; the model of the auxiliary chip may be PIC16F1824; the model of the storage chip may be M95160-DRMN3TP / K; the model of the driver chip may be A4935KJPTR-T; the model of the CAN transceiver may be TJA1042T; and the model of the motor position chip may be TAD2141.

[0075] In an optional embodiment, if Figure 2 As shown, the input shaft 21 and the worm gear reduction mechanism 241 are both coupled with the rack 25 through gears to achieve left and right movement of the rack 25.

[0076] In an optional embodiment, the steering gear controller 23, the power assist device 24 and the rack 25 are all integrated in the main housing 22. Compared with the electro-hydraulic power assist structure, the system has a higher degree of integration, space utilization and modularization, is easy to maintain, has lower maintenance costs, and at the same time reduces the overall weight of the system. The space layout in the vehicle is flexible and can be adjusted according to the progress of surrounding components to improve space utilization.

[0077] The structure of the steering column 1 is described in detail below:

[0078] In an alternative embodiment, if Figures 3 to 5 As shown, the steering column 1 includes an upper column 11, a lower column 12 and a stopper 13. The upper column 11 is slidably matched with the lower column 12 along the extension direction of the lower column 12, and a clamping structure for increasing friction is provided between the upper column 11 and the lower column 12. The stopper 13 is connected to the upper column 11, and the stopper 13 is configured to limit the position of the upper column 11 when the pressure between the upper column 11 and the lower column 12 is less than a first threshold value, and to be loosened from the upper column 11 when the pressure between the upper column 11 and the lower column 12 is greater than the first threshold value.

[0079] The above arrangement allows the steering column 1 to have a margin for collapse. When the steering wheel is hit head-on in an unexpected situation, the impact force is directly transmitted to the upper column 11. If the above first threshold is 4500N, then when the impact force reaches the critical value of 4500N, the limiter 13 is loosened from the upper column 11, and the upper column and the lower column use mutual friction to absorb the energy generated by the impact, thereby protecting the driver. Together with the airbag on the steering wheel, it can effectively prevent the driver from being injured by the impact.

[0080] The above-mentioned first threshold is not limited to 4500N, but may also be less than 4500N, such as 4300N, 4000N or 3800N, or slightly greater than 4500N, such as 4550N, 4600N or 4650N, so that the limit member 13 can be loosened from the upper column 11 in time after the steering wheel is subjected to a strong impact.

[0081] In an alternative embodiment, if Figure 3 As shown, the tube body 111 in the upper tube column 11 is sleeved on the outside of the lower tube column 12 , and the clamping structure includes a plurality of protrusions 1111 protruding from the inner wall of the tube body 111 to the outer wall of the lower tube column 12 .

[0082] In the above embodiment, the multiple protrusions 1111 can press against the outer surface of the lower column 12, so that after the limit piece 13 is loosened from the upper column 11, the upper column 11 moves relative to the lower column 12, and the impact force is offset by the friction force, ensuring that the impact force is maintained at about 2000N during collapse. In conjunction with the airbag on the steering wheel, it can effectively protect the driver and reduce the damage caused by accidents.

[0083] Specifically, a plurality of protrusions 1111 may be provided, and the plurality of protrusions 1111 are evenly distributed around the circumference of the tube body 111 .

[0084] Specifically, Figure 6 and Figure 7 As shown, the upper column 11 includes a mounting bracket 112 connected to the limiting member 13, and the limiting member 13 includes a limiting block 131 and a limiting strip 132. One end of the limiting strip 132 is covered on the outside of the limiting member 13 to achieve a clamping connection with the limiting member 13, and the other end passes through the mounting bracket 112 and guides the movement of the mounting bracket 112 during collapse along its own extension direction. The limiting block 131 and the limiting strip 132 are both provided with connecting holes, and bolts and other connecting parts can pass through the connecting holes of the two to connect the limiting block 131 and the limiting strip 132 to the frame.

[0085] When the steering wheel is hit head-on, the impact force is directly transmitted to the upper column 11. When the impact force reaches a first threshold, the limiter 13 and the mounting bracket 112 in the upper column 11 are loosened, and the upper column 11 as a whole can move relative to the lower column 12 to absorb the energy generated by the impact through friction.

[0086] like Figure 5 As shown, the mounting bracket 112 has a clamping portion 1121 that holds the limiting block 131 . Under the action of the impact force, the clamping portion 1121 is destroyed, thereby achieving the loosening of the mounting bracket 112 and the limiting block 131 .

[0087] In an optional embodiment, the limit member 13 is used to be installed on the frame, and the power steering system also includes a second sensor and a limit member controller, and the second sensor and the limit member 13 are both connected to the limit member controller signal; the second sensor is used to detect the impact force on the steering wheel and convert it into a force signal, and the limit member controller is used to receive the force signal and control the limit member 13 to loosen from the frame when the impact force is greater than a second threshold value.

[0088] During use, since the mounting bracket 112 and the limit piece 13 in the upper column 11 are mechanically clamped, after the steering wheel is hit, the connection structure between the mounting bracket 112 and the limit piece 13 is destroyed to achieve the loosening of the mounting bracket 112 and the limit block 131. However, due to the influence of processing technology and other reasons, it cannot be effectively guaranteed that when the pressure between the upper column 11 and the lower column 12 is greater than the first threshold, the mounting bracket 112 will definitely loosen from the limit block 131. Therefore, the above embodiment makes a redundant design.

[0089] The second sensor may be a pressure sensor, which is used to detect the impact force exerted on the steering wheel and convert it into a force signal. The limit member controller can receive the force signal and control the limit member 13 to loosen from the frame when the impact force is greater than a second threshold value. Even if the mounting bracket 112 is not loosened from the limit block 131 under the action of the above-mentioned impact force, the upper column 11 can be moved relative to the lower column 12, which has a double protection effect.

[0090] In an optional implementation, the second threshold is equal to the first threshold.

[0091] Of course, the second threshold value may also be slightly larger than the first threshold value, for example, larger than the first threshold value by 20N, 50N or 100N, so that when the pressure between the upper tube column 11 and the lower tube column 12 is larger than the first threshold value, the limit member controller controls the limit member 13 to loosen from the frame when the mounting bracket 112 is not loosened from the limit block 131.

[0092] On the basis of the above embodiment, the limiter 13 may be provided with structures such as an electric claw connected to the frame, the electric claw is connected to the limiter controller, and when the impact force is greater than the second threshold, the limiter controller controls the electric claw to loosen from the frame.

[0093] In an alternative embodiment, if Figure 6 and Figure 7 As shown, the upper pipe column 11 further includes an adjusting member 113 , which is connected between the mounting bracket 112 and the pipe body 111 , and is used to adjust and lock the mounting angle of the pipe body 111 relative to the mounting bracket 112 .

[0094] When in use, the lower tube column 12 can be rotatably connected to the frame 18, and the position of the tube body 111 relative to the mounting bracket 112 can be unlocked by the adjusting member 113, and then the tube body 111 can be rotated. At this time, the tube body 111 drives the lower tube column 12 to rotate relative to the frame 18. After rotating to a suitable position, the position of the tube body 111 relative to the mounting bracket 112 can be locked by the adjusting member 113.

[0095] Specifically, the upper column 11 can be adjusted up and down by ±3° relative to the mounting bracket 112 to meet the needs of drivers of different body shapes.

[0096] Specifically, waist-shaped grooves may be provided on both sides of the mounting bracket 112. Figure 4As shown, the adjusting member 113 may include a connecting shaft 1131, a bracket 1132 and a handle 1133; one end of the connecting shaft 1131 passes through the waist-shaped groove on one side of the mounting bracket 112 and is rotatably connected to the handle 1133, and the other end of the connecting shaft 1131 passes through the waist-shaped groove on the other side of the mounting bracket 112 and abuts against the outer surface of the mounting bracket 112 to limit the position of the connecting shaft 1131 along its own axial direction relative to the mounting bracket 112; the bracket 1132 is fixedly connected to the connecting shaft 1131, and the bracket 1132 is in a U-shape with an opening facing upward, and a bending plate is obliquely extended upward from the top end of the bracket 1132, and the bending plate is fixedly connected to the tube body 111.

[0097] When in use, the handle 1133 can be rotated forward to loosen the handle 1133 so that the handle 1133 can stop pressing the mounting bracket 112, and the user can adjust the angle of the tube body 111 relative to the mounting bracket 112. After the adjustment, the handle 1133 can be rotated in the reverse direction to tighten the handle 1133 so that the handle 1133 and the end of the connecting shaft 1131 can clamp the mounting bracket 112 together and lock the position of the tube body 111.

[0098] Specifically, the handle 1133 can be threadedly matched with the connecting shaft 1131.

[0099] In an alternative embodiment, if Figure 6 As shown, the steering column 1 also includes an intermediate shaft 14, a first universal joint 15, a second universal joint 16 and an output shaft 17. One end of the intermediate shaft 14 is rotatably connected to an end of the lower column 12 away from the upper column 11 through the first universal joint 15, and the other end of the intermediate shaft 14 is rotatably connected to the output shaft 17 through the second universal joint 16. The output shaft 17 is connected to the input shaft 21.

[0100] When in use, the power of the upper column 11 can be transmitted to the intermediate shaft 14 and the output shaft 17 through the lower column 12, and then transmitted to the input shaft 21 of the steering gear 2 through the output shaft 17. The setting of the first universal joint 15 and the second universal joint 16 can adapt to the changes in the extension direction of the intermediate shaft 14 during the power transmission process, and effectively transmit the power to the output shaft 17 without getting stuck.

[0101] In an optional embodiment, the first universal joint 15 and the second universal joint 16 each include a first joint 151, a second joint 152 and a connecting frame 153, the connecting frame 153 may be in a cross shape, the first joint 151 rotates with the connecting frame 153 around a first direction and the rotation angle is greater than 40°, the second joint 152 rotates with the connecting frame 153 around a second direction and the rotation angle is greater than 40°, and the second direction is perpendicular to the first direction.

[0102] The above setting can control the torque fluctuation generated during steering to ≤1%, making the steering smoother.

[0103] like Figure 6 As shown, the intermediate shaft 14 includes an upper intermediate shaft 141 and a lower intermediate shaft 142 slidably matched with the upper intermediate shaft along an extending direction of the upper intermediate shaft 141 .

[0104] Specifically, the first joint 151 in the first universal joint 15 is fixedly connected to the lower tube column 12, the second joint 152 in the first universal joint 15 is fixedly connected to the upper intermediate shaft 141, the first joint 151 in the second universal joint 16 is fixedly connected to the lower intermediate shaft 142, and the second joint 152 in the second universal joint 16 is fixedly connected to the output shaft 17.

[0105] An embodiment of the second aspect of the present invention provides a commercial vehicle. The commercial vehicle provided by the embodiment of the second aspect of the present invention includes the above-mentioned power steering system.

[0106] When the above-mentioned commercial vehicle is in use, under the premise of ensuring that the small battery inside the vehicle provides DC12V power supply, the vehicle ignition generates a READY signal and transmits it to the steering gear controller 23 and the vehicle controller. The steering gear controller 23 can control the power-assisting device 24 to provide an initial power assist to ensure that the driver has power assist when steering. After the driver turns the steering wheel, the first sensor detects the parameter information of the rotation process of the input shaft 21 and converts it into a first electrical signal. The vehicle controller generates a power assist curve based on the first electrical signal, the vehicle speed signal and the vehicle start signal and converts it into a curve signal. The steering gear controller 23 adjusts the magnitude of the power assist output by the power-assisting device 24 according to the curve signal.

[0107] The commercial vehicle provided in the second aspect of the present invention has the power steering system provided in the embodiment of the first aspect of the present invention, thereby having all the beneficial effects of the power steering system provided in the embodiment of the first aspect of the present invention.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power steering system, characterized in that: The invention comprises a steering column (1), a steering gear (2) and a vehicle controller, wherein the steering gear (2) comprises an input shaft (21), a main housing (22), a steering gear controller (23), a power assist device (24) and a rack (25), and the steering column (1) is connected to the input shaft (21); The input shaft (21) is rotationally connected to the main housing (22) and is provided with a first sensor, the first sensor is used to detect parameter information of the rotation process of the input shaft (21) and convert it into a first electrical signal, the first sensor and the steering gear controller (23) are both connected to the vehicle controller by signal, the vehicle controller is used to generate a power assistance curve according to the first electrical signal, a vehicle speed signal and a vehicle start signal and convert it into a curve signal, the steering gear controller (23) is connected to the power assist device (24) by signal, the steering gear controller (23) is used to adjust the magnitude of the power assistance output by the power assist device (24) according to the curve signal, and the power assist device (24) comprises a worm gear reduction mechanism (241); The input shaft (21) and the worm gear reduction mechanism (241) are both in transmission cooperation with the rack (25).

2. The power steering system according to claim 1, characterized in that: The steering column (1) comprises an upper column (11), a lower column (12) and a stopper (13); the upper column (11) is slidably matched with the lower column (12) along the extension direction of the lower column (12); and a clamping structure for increasing friction is provided between the upper column (11) and the lower column (12); The limiter (13) is connected to the upper tubular column (11), and the limiter (13) is configured to limit the position of the upper tubular column (11) when the pressure between the upper tubular column (11) and the lower tubular column (12) is less than a first threshold value, and to be loosened from the upper tubular column (11) when the pressure between the upper tubular column (11) and the lower tubular column (12) is greater than the first threshold value.

3. The power steering system according to claim 2, characterized in that: The limiter (13) is used to be installed on a vehicle frame, and the power steering system further comprises a second sensor and a limiter controller, and the second sensor and the limiter (13) are both connected to the limiter controller by signal. The second sensor is used to detect the impact force on the steering wheel and convert it into a force signal, and the limiter controller is used to receive the force signal and control the limiter (13) to loosen from the frame when the impact force is greater than a second threshold value.

4. The power steering system according to claim 3, characterized in that: The second threshold is equal to the first threshold.

5. The power steering system according to claim 2, characterized in that: The upper pipe column (11) is sleeved on the outside of the lower pipe column (12), and the clamping structure comprises a plurality of protrusions (1111) protruding from the inner wall of the upper pipe column (11) toward the outer wall of the lower pipe column (12).

6. The power steering system according to claim 2, characterized in that: The upper pipe column (11) comprises a pipe body (111), a mounting bracket (112) and an adjusting member (113); the mounting bracket (112) is connected to the limiting member (13); the adjusting member (113) is connected between the mounting bracket (112) and the pipe body (111); the adjusting member (113) is used to adjust and lock the mounting angle of the pipe body (111) relative to the mounting bracket (112).

7. The power steering system according to claim 2, characterized in that: The steering column (1) further comprises an intermediate shaft (14), a first universal joint (15), a second universal joint (16) and an output shaft (17); one end of the intermediate shaft (14) is rotatably connected to an end of the lower column (12) away from the upper column (11) via the first universal joint (15); the other end of the intermediate shaft (14) is rotatably connected to the output shaft (17) via the second universal joint (16); and the output shaft (17) is connected to the input shaft (21).

8. The power steering system according to claim 7, characterized in that: The first universal joint (15) and the second universal joint (16) both comprise a first joint (151), a second joint (152) and a connecting frame (153); the first joint (151) is rotatably matched with the connecting frame (153) around a first direction and the rotation angle is greater than 40°; the second joint (152) is rotatably matched with the connecting frame (153) around a second direction and the rotation angle is greater than 40°; the second direction is perpendicular to the first direction.

9. The power steering system according to claim 1, characterized in that: The power assist device (24) further comprises a motor (242), the motor (242) being connected to the steering gear controller (23) by signal, and the motor (242) being in transmission cooperation with the rack (25) via the worm gear reduction mechanism (241).

10. A commercial vehicle, characterized in that: It comprises a power steering system as claimed in any one of claims 1 to 9.

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