A kind of steering wheel number of turns limiter for steer-by-wire system

Abstract

The application relates to the technical field of automobile steering, in particular to a steering wheel circle number limiter for a steer-by-wire system, which comprises a mounting shell, a steering shaft and a hand feeling simulator, the mounting shell is sleeved on the outer side of the steering shaft; the front end of the mounting shell is fixed with an operation box body, and a limiting assembly for limiting the steering shaft during steering is arranged in the operation box body. The steering wheel circle number limiter for the steer-by-wire system can make the threaded rod, the steering shaft and the steering wheel unable to continue rotating after rotating to a certain degree through the mutual cooperation of the limiting assembly, the transmission assembly and the guide assembly, thereby achieving the effect of limiting the steering wheel rotation circle number of the steer-by-wire system, the steering wheel limiting function of the steer-by-wire system can be realized in the whole limiting process, the burden of the hand feeling simulator and other components is released, the limiting is realized through a mechanical structure, the stable steering wheel circle number is guaranteed, and the driving experience is improved.

Description

Technical Field

[0001] This invention relates to the field of automotive steering technology, specifically to a steering wheel turn limiter for a steer-by-wire system. Background Technology

[0002] Automotive steering systems are mainly divided into non-steerable-by-wire systems and steerable-by-wire systems. In non-steerable-by-wire systems, all components from the input (steering wheel) to the output (steering gear) are mechanically connected. Therefore, the steering wheel turn limit function is actually achieved through the limiting relationship between the end of the steering gear rack and the steering gear housing. However, in steerable-by-wire systems, because the intermediate shaft in the middle of the steering system is removed, the entire system is not entirely composed of mechanical components. If the steering wheel is not limited and allowed to rotate freely, it will damage precision electrical components such as the clock spring and torque angle sensor, leading to system malfunction and affecting driving safety. Therefore, steerable-by-wire systems must include a steering wheel turn limit function. Currently, the steering wheel turn limit function in steerable-by-wire systems is achieved by the steerable-by-wire controller controlling the motor, which applies resistance to the worm gear mechanism in the steering simulator, thereby limiting the number of steering wheel turns.

[0003] The disadvantages of steer-by-wire systems with steering wheel turn limiters are as follows: 1. High stress on components such as the worm gear and worm: When the driver turns the steering wheel with great force, the tooth surface of the worm gear and the axial force of the worm are large, which will reduce the performance of the steer-by-wire system and shorten its service life; 2. Software-based limiter: It fails when the vehicle is powered off for a long time or when the vehicle has no battery, the worm gear mechanism in the hand-feel simulator cannot receive the resistance of the motor, and therefore cannot limit the number of steering wheel turns; 3. Requires self-learning adjustment and center alignment: Because the limiter is controlled by software, the sensors in the hand-feel simulator need to self-learn and adjust periodically to align the center position, which will lead to unstable steering wheel turn counts and affect the driving experience. Summary of the Invention

[0004] To address the problems in the prior art, the present invention provides a steering wheel turn limiter for a steer-by-wire system.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a steering wheel turn limiter for a steer-by-wire system, comprising a mounting housing, a steering shaft and a hand feel simulator, wherein the mounting housing is sleeved on the outside of the steering shaft; an operating box is fixed to the front end of the mounting housing, and a limiting component for limiting the steering shaft during the steering process is provided inside the operating box;

[0006] The limiting component includes two sliders symmetrically arranged inside the operating housing. The operating housing contains a strip plate, with the two sliders located between the two strip plates. Two limiting plates are fixed to the strip plates to limit the sliders' contact. The operating housing contains a transmission component for driving the two sliders and a first guide component for guiding the sliders during transmission. The operating housing also contains an adjustment component for adjusting the distance between the two strip plates and a second guide component for guiding the sliders during adjustment. The limiting plates contain a buffer component for cushioning the sliders during limiting.

[0007] The transmission assembly includes a threaded rod rotatably connected to the inside of the operating box, a transmission plate being threadedly engaged on the threaded rod, and two sliders being symmetrically fixed on both sides of the transmission plate.

[0008] The first guide assembly includes a first guide hole formed on two sliders, a first guide rod slidably connected to the first guide hole, and the first guide rod is fixed inside the operating box.

[0009] The adjustment assembly includes a double-ended lead screw rotatably connected inside the operating box, threaded sleeves fixed on the two strip plates, and the two threaded sleeves respectively engaging with the two ends of the double-ended lead screw. A drive motor for driving the double-ended lead screw is installed on the outside of the operating box.

[0010] The threads at both ends of the double-ended lead screw are arranged in opposite directions.

[0011] The second guide assembly includes multiple second guide holes formed on two strip plates, and a second guide rod is slidably connected to each second guide hole. The second guide rod is fixed inside the operating box.

[0012] The buffer assembly includes a mounting cylinder fixed to a limiting plate, a sliding plate slidably connected to the mounting cylinder, a sliding rod slidably connected to one end of the mounting cylinder near the slider, one end of the sliding rod being fixed to the sliding plate, the interior of the mounting cylinder being filled with damping fluid, and a first control component and multiple sets of second control components for controlling the flow of damping fluid being provided on the sliding plate.

[0013] The mounting cylinder contains a connecting spring for connecting the slide plate.

[0014] The first control component includes a first mounting hole formed on the slide plate, and a first one-way valve is installed on the first mounting hole. The conduction direction of the first one-way valve is from one side of the slide plate inside the mounting cylinder away from the slide bar to the other side.

[0015] The second control component includes a second mounting hole formed on the slide plate, on which a second check valve is mounted, the second check valve being configured opposite to the first check valve.

[0016] The beneficial effects of this invention are:

[0017] The present invention discloses a steering wheel rotation limiter for a steer-by-wire system. Through the cooperation of a limiter component, a transmission component, and a guide component, the threaded rod, steering shaft, and steering wheel are prevented from rotating further after reaching a certain degree of rotation. This effectively limits the number of steering wheel rotations in the steer-by-wire system. During the entire limiting process, the steer-by-wire system can achieve the steering wheel limiting function without relying on software limiting, thus relieving the burden on components such as the hand feel simulator. Furthermore, the mechanical limiting structure ensures a stable number of steering wheel rotations, thereby improving the driving experience. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This invention provides a schematic diagram of the overall external structure of a steering wheel turn limiter for a steer-by-wire system.

[0020] Figure 2 This invention provides a schematic diagram of a limiting component and a first guide component for a steering wheel turn limiter in a steer-by-wire system.

[0021] Figure 3 A schematic diagram of an adjustment component and a second guide component for a steering wheel turn limiter in a steer-by-wire system provided by the present invention;

[0022] Figure 4 This invention provides a schematic diagram of a buffer assembly structure for a steering wheel turn limiter in a steer-by-wire system.

[0023] Figure 5 for Figure 4 A magnified structural diagram of point A in the middle.

[0024] In the diagram: 101, mounting housing; 102, steering shaft; 103, hand-feel simulator; 2, operating box; 301, slider; 302, strip plate; 303, limiting plate; 401, first guide hole; 402, first guide rod; 501, threaded rod; 502, transmission plate; 601, double-ended lead screw; 602, threaded sleeve; 603, drive motor; 701, second guide hole; 702, second guide rod; 801, mounting cylinder; 802, sliding plate; 803, sliding rod; 9, connecting spring; 1001, first mounting hole; 1002, first one-way valve; 1101, second mounting hole; 1102, second one-way valve. Detailed Implementation

[0025] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. It should be noted that the illustrations provided in the following embodiments are for illustrative purposes only and represent schematic diagrams, not actual pictures, and should not be construed as limiting the present invention. In order to better illustrate the embodiments of the present invention, some components in the figures may be omitted, enlarged, or reduced, and do not represent the actual product size; it is understandable for those skilled in the art that some well-known structures and their descriptions may be omitted in the figures.

[0026] In the figures of this invention, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figure, they are only for the convenience of describing this invention and simplifying the description, 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, the terms used to describe positional relationships in the figures are only for illustrative purposes and should not be construed as limiting this invention. For those skilled in the art, the specific meaning of the above-mentioned terms can be understood according to the specific circumstances.

[0027] like Figure 1-5 As shown, a steering wheel turn limiter for a steer-by-wire system according to the present invention includes a mounting housing 101, a steering shaft 102, and a hand feel simulator 103. The mounting housing 101 is sleeved on the outside of the steering shaft 102. An operating box 2 is fixed to the front end of the mounting housing 101, and a limit component for limiting the steering shaft 102 during steering is provided inside the operating box 2.

[0028] Through the cooperation of the limiting component, transmission component and guiding component, the threaded rod 501, steering shaft 102 and steering wheel can no longer rotate after rotating to a certain extent, which achieves the effect of limiting the number of turns of the steering wheel in the steer-by-wire system. In the process of limiting, the steering wheel limiting function of the steer-by-wire system can be realized, without the need for software limiting, which relieves the burden on components such as the hand feel simulator, and ensures a stable number of steering wheel turns through mechanical limiting, thereby improving the driving experience.

[0029] The limiting assembly includes two sliders 301 symmetrically arranged inside the operating housing 2. The operating housing 2 contains a strip plate 302, with the two sliders 301 positioned between the two strip plates 302. Two limiting plates 303 are fixed to the strip plates 302 to limit the sliders 301 from moving against each other. The operating housing 2 contains a transmission assembly for driving the two sliders 301 and a first guide assembly for guiding the sliders 301 during transmission. The operating housing 2 also contains an adjustment assembly for adjusting the distance between the two strip plates 302 and a second guide assembly for guiding the sliders during adjustment. A buffer assembly is provided on the limiting plates 303 to cushion the sliders 301 during limiting. The transmission assembly includes a threaded rod 501 rotatably connected inside the operating housing 2, with a transmission plate 502 threadedly engaged on the threaded rod 501. 301 is symmetrically fixed on both sides of the transmission plate 502; the first guide assembly includes a first guide hole 401 opened on the two sliders 301, and a first guide rod 402 is slidably connected to the first guide hole 401. The first guide rod 402 is fixed inside the operating box 2; during the rotation of the steering shaft 102, the threaded rod 501 is driven to rotate inside the operating box 2. During the rotation of the threaded rod 501, the transmission plate 502 and the two sliders 301 are driven to move through the mutual meshing transmission between the threaded rod 501 and the transmission plate 502. During the movement of the two sliders 301, the two sliders 301 slide between the two strip plates 302 after being subjected to force through the guiding effect of the first guide hole 401 and the first guide rod 402. During the sliding process, the movement of the sliders 301 is blocked and limited by the limiting plate 303.

[0030] Specifically, the adjusting assembly includes a double-ended lead screw 601 rotatably connected inside the operating housing 2, and threaded sleeves 602 fixed on two strip plates 302. The two threaded sleeves 602 are respectively engaged with the two ends of the double-ended lead screw 601. A drive motor 603 for driving the double-ended lead screw 601 is installed on the outside of the operating housing 2. The threads at both ends of the double-ended lead screw 601 are arranged in opposite directions. The second guiding assembly includes multiple second guide holes 701 opened on the two strip plates 302, and a second guide rod 702 is slidably connected to each second guide hole 701. The second guide rod 702 is fixed inside the operating housing 2. During the limiting process, the double-ended lead screw 601 is driven by the drive motor 603 to advance. As the double-ended lead screw 601 rotates, the threads at both ends of the double-ended lead screw 601 are set in opposite directions. During the rotation of the double-ended lead screw 601, the two strip plates 302 are driven to move under force through the mutual meshing transmission between the double-ended lead screw 601 and the two threaded sleeves 602 respectively. During the movement of the two strip plates 302, the sliding guidance effect of the second guide hole 701 and the second guide rod 702 causes the two strip plates 302 to move closer or further apart after being subjected to force, adjusting the distance between the upper limit plates 303 of the two strip plates 302. By adjusting the distance, the steering wheel of the steer-by-wire system can be limited at different steering turns, adapting to different conditions for limit protection.

[0031] Specifically, the buffer assembly includes a mounting cylinder 801 fixed on the limiting plate 303, a sliding plate 802 slidably connected to the mounting cylinder 801, a sliding rod 803 slidably connected to one end of the mounting cylinder 801 near the slider 301, one end of the sliding rod 803 being fixed to the sliding plate 802, the interior of the mounting cylinder 801 being filled with damping fluid, and the sliding plate 802 being provided with a first control component and multiple sets of second control components for controlling the flow of damping fluid.

[0032] Specifically, the mounting cylinder 801 is equipped with a connecting spring 9 for connecting the slide plate 802; the connecting spring 9 facilitates the reset movement of the slide plate 802 after being subjected to force.

[0033] Specifically, the first control component includes a first mounting hole 1001 formed on the slide plate 802, on which a first one-way valve 1002 is installed. The conduction direction of the first one-way valve 1002 is from one side of the slide plate 802 inside the mounting cylinder 801 away from the slide rod 803 to the other side. During the process of limiting the slider 301 by the limiting plate 303, as the slider 301 moves towards the limiting plate 303, the slider 301 abuts against the slide rod 803, pushing the slide plate 802 in the mounting cylinder. The internal sliding of the cylinder 801 is achieved because the conduction direction of the first one-way valve 1002 is from one side of the internal sliding plate 802 of the mounting cylinder 801 away from the sliding rod 803 to the other side, and the second one-way valve 1102 is set opposite to the first one-way valve 1002. Through the sliding of the sliding plate 802 against each other, the damping fluid inside the mounting cylinder 801 passes through only the single first one-way valve 1002, generating a damping mechanism. This reduces the force of the slider 301 against the limiting plate 303, thus protecting the limiting plate 303.

[0034] Specifically, the second control component includes a second mounting hole 1101 on the slide plate 802, and a second one-way valve 1102 is installed on the second mounting hole 1101. The second one-way valve 1102 is arranged opposite to the first one-way valve 1002. When the slider 301 does not abut against the slide rod 803, the slide plate 802 is pushed to reset by the connecting spring 9. During the reset process, the resistance fluid inside the mounting cylinder 801 passes through each of the second one-way valves 1102, which reduces the damping effect and facilitates the rapid reset of the slide plate 802. The rapid reset of the slide plate 802 facilitates subsequent efficient damping and buffering protection.

[0035] Working principle: When the steer-by-wire system is in operation, the steering shaft 102 is driven to rotate by the steering wheel. During the rotation of the steering shaft 102, the car wheels are driven to steer by the cooperation between the steering shaft 102 and the hand feel simulator 103.

[0036] During the rotation of the steering shaft 102, the threaded rod 501 is driven to rotate inside the operating box 2. During the rotation of the threaded rod 501, the transmission plate 502 is driven to move through the meshing transmission between the threaded rod 501 and the transmission plate 502. During the movement of the two sliders 301, the first guide hole 401 and the first guide rod 402 guide the two sliders 301 to slide between the two strip plates 302 after being subjected to force. During the sliding process, the movement of the sliders 301 is blocked and limited by the limiting plate 303, so that the threaded rod 501, the steering shaft 102 and the steering wheel cannot continue to rotate after rotating to a certain extent. This achieves the effect of limiting the number of turns of the steering wheel in the steer-by-wire system. During the entire limiting process, the steering wheel limiting function of the steer-by-wire system can be realized, the limiting function can be realized without the aid of software, the burden on the hand feel simulator and other components can be relieved, and the limiting function of mechanical structure can be used to ensure a stable number of steering wheel turns, thereby improving the driving experience.

[0037] During the limiting process, the double-ended lead screw 601 is driven to rotate by the drive motor 603. Since the threads at both ends of the double-ended lead screw 601 are set in opposite directions, during the rotation of the double-ended lead screw 601, the two strip plates 302 are driven to move under force through the mutual meshing transmission between the double-ended lead screw 601 and the two threaded sleeves 602 respectively. During the movement of the two strip plates 302, the sliding guidance of the second guide hole 701 and the second guide rod 702 causes the two strip plates 302 to move closer or further apart after being subjected to force, thereby adjusting the distance between the upper limit plate 303 of the two strip plates 302. By adjusting the distance, the steering wheel of the steer-by-wire system can be limited at different steering turns, adapting to different conditions for limiting protection.

[0038] During the process of limiting the slider 301 by the limiting plate 303, as the slider 301 moves towards the limiting plate 303, it abuts against the slide rod 803, pushing the slide plate 802 to slide inside the mounting cylinder 801. Because the conduction direction of the first one-way valve 1002 is from the side of the slide plate 802 inside the mounting cylinder 801 away from the slide rod 803 to the other side, and the second one-way valve 1102 is set opposite to the first one-way valve 1002, through the sliding of the slide plate 802, the damping fluid inside the mounting cylinder 801 is only released from a single... The first one-way valve 1002 passes through, creating a damping mechanism that reduces the impact force of the slider 301 against the limit plate 303, thus protecting the limit plate 303. When the slider 301 is not against the slide bar 803, the connecting spring 9 pushes the slide plate 802 to reset. During the reset process, the resistance fluid inside the mounting cylinder 801 passes through each of the second one-way valves 1102, which reduces the damping effect and facilitates the rapid reset of the slide plate 802. The rapid reset of the slide plate 802 facilitates subsequent efficient damping and buffering protection.

[0039] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention. Technical aspects, shapes, and structures not described in detail in this invention are all well-known technologies.

Claims

1. A steering wheel turn limiter for a steer-by-wire system, comprising a mounting housing (101), a steering shaft (102), and a steering gear (103), wherein the mounting housing (101) is sleeved on the outside of the steering shaft (102); characterized in that: The front end of the mounting housing (101) is fixed with an operating box (2), and the inside of the operating box (2) is provided with a limiting component for limiting the steering shaft (102) during the steering process; The limiting component includes two sliders (301) symmetrically arranged inside the operating box (2). The operating box (2) is provided with two strip plates (302). The two sliders (301) are located between the two strip plates (302). Two limiting plates (303) for limiting the sliders (301) to abut against each other are fixed on the strip plates (302). The operating box (2) is provided with a transmission component for driving the two sliders (301) and a first guide component for guiding the sliders (301) during the transmission process. The operating box (2) is provided with an adjustment component for adjusting the distance between the two strip plates (302) and a second guide component for guiding the sliders during the adjustment process. The limiting plate (303) is provided with a buffer component for buffering the sliders (301) during the limiting process. The transmission assembly includes a threaded rod (501) rotatably connected inside the operating box (2), and a transmission plate (502) is threadedly engaged on the threaded rod (501). Two sliders (301) are symmetrically fixed on both sides of the transmission plate (502). The first guide assembly includes a first guide hole (401) opened on two sliders (301), a first guide rod (402) is slidably connected to the first guide hole (401), and the first guide rod (402) is fixed inside the operating box (2); The adjustment assembly includes a double-ended lead screw (601) rotatably connected inside the operating housing (2), and threaded sleeves (602) fixed on the two strip plates (302). The two threaded sleeves (602) are respectively engaged with the two ends of the double-ended lead screw (601). A drive motor (603) for driving the double-ended lead screw (601) is installed on the outside of the operating housing (2). The threads at both ends of the double-ended lead screw (601) are arranged in opposite directions; The second guide assembly includes a plurality of second guide holes (701) formed on two strip plates (302), and a second guide rod (702) is slidably connected to each of the second guide holes (701), and the second guide rod (702) is fixed inside the operating box (2); The buffer assembly includes a mounting cylinder (801) fixed on a limiting plate (303), a sliding plate (802) slidably connected to the mounting cylinder (801), a sliding rod (803) slidably connected to one end of the mounting cylinder (801) near the slider (301), one end of the sliding rod (803) being fixed to the sliding plate (802), the interior of the mounting cylinder (801) being filled with damping fluid, and the sliding plate (802) being provided with a first control component and multiple sets of second control components for controlling the flow of damping fluid; The mounting cylinder (801) is equipped with a connecting spring (9) for connecting to the sliding plate (802). The first control component includes a first mounting hole (1001) opened on the slide plate (802), and a first one-way valve (1002) is installed on the first mounting hole (1001). The conduction direction of the first one-way valve (1002) is from one side of the inner slide plate (802) of the mounting cylinder (801) away from the slide rod (803) to the other side.

2. A steering wheel turn limiter for a steer-by-wire system according to claim 1, characterized in that: The second control component includes a second mounting hole (1101) formed on the slide plate (802), on which a second check valve (1102) is mounted, the second check valve (1102) being arranged opposite to the first check valve (1002).

Images