An independently steerable axle for heavy-load vehicles

Abstract

The present invention discloses an independently steerable axle for heavy-loaded vehicles, comprising: a bridge housing; a hydraulic oil tank, which is fixedly arranged in the bridge housing; a first motor pump, whose oil inlet is connected to the hydraulic oil tank; two hydraulic motors, whose power output ends are respectively connected to the upper ends of the steering knuckles of the wheels on both sides of the bridge housing, for driving the steering knuckles to rotate; wherein the hydraulic motor comprises a first oil circuit and a second oil circuit; when oil is fed through the first oil circuit or the second oil circuit, the rotation direction of the hydraulic motor is different; a second motor pump, whose oil inlet is connected to the hydraulic oil tank; two oil-gas springs, which are arranged in a one-to-one correspondence with the two lower cross arms; one end of the oil-gas spring is rotationally connected to the lower cross arm, and the other end is rotationally connected to the bridge housing; wherein the oil hole of the oil-gas spring is selectively connected to the oil outlet of the second motor pump; two brakes, which are arranged in a one-to-one correspondence with the wheels on both sides of the bridge housing; the oil hole of the brake is selectively connected to the oil outlet of the second motor pump.

Description

Technical Field

[0001] The invention belongs to the technical field of electric vehicles, and in particular relates to an independently steerable axle for heavy-load vehicles. Background Art

[0002] Against the backdrop of electrification in the automotive industry, vehicles powered by in-wheel motors have already been commercialized in some heavy-duty vehicles. Heavy-duty vehicles require a high degree of chassis space, necessitating chassis system integration.

[0003] In heavy-duty vehicles powered by in-wheel motors, the ability to independently steer individual wheels would significantly enhance the vehicle's maneuverability and is of great research significance. Furthermore, individually controlling each wheel can improve the vehicle's handling stability. Summary of the Invention

[0004] The purpose of the present invention is to provide an independently steerable axle for heavy-loaded vehicles, which can realize independent driving, steering, braking and other functions of individual wheels of heavy-loaded vehicles, so that each wheel can be controlled individually; and can improve space utilization.

[0005] The technical solution provided by the present invention is:

[0006] An independently steerable axle for a heavy-load vehicle, comprising:

[0007] axle housing;

[0008] a hydraulic oil tank, which is fixedly arranged in the axle housing;

[0009] a first motor pump, which is fixedly installed in the axle housing, and an oil inlet of the first motor pump is connected to the hydraulic oil tank;

[0010] Two hydraulic motors, whose power output ends are respectively connected to the upper ends of the steering knuckles of the wheels on both sides of the axle housing, for driving the steering knuckles to rotate;

[0011] The hydraulic motor includes a first oil circuit and a second oil circuit; the first oil circuit is selectively connected to the oil outlet of the first motor pump or the hydraulic oil tank, and the second oil circuit is selectively connected to the oil outlet of the first motor pump or the hydraulic oil tank; when the hydraulic motor is supplied with oil through the first oil circuit or the second oil circuit, the rotation direction of the hydraulic motor is different;

[0012] Two lower cross arms, each provided on either side of the axle housing, one end of each lower cross arm being rotatably connected to the lower end of the steering knuckle, and the other end being rotatably connected to the axle housing;

[0013] a second motor pump, which is fixedly installed in the axle housing, and an oil inlet of the second motor pump is connected to the hydraulic oil tank;

[0014] Two oil-gas springs are provided in a one-to-one correspondence with the two lower transverse arms; one end of the oil-gas spring is rotatably connected to the lower transverse arm, and the other end is rotatably connected to the axle housing;

[0015] Wherein, the oil hole of the oil-gas spring is selectively connected to the oil outlet of the second motor pump;

[0016] Two brakes are provided corresponding to the wheels on both sides of the bridge housing in a one-to-one manner; the oil holes of the brakes are selectively connected to the oil outlet of the second motor pump.

[0017] Preferably, the independently steerable axle for heavy-load vehicles further comprises:

[0018] Two upper cross arm bases, which are rotatably mounted on the upper ends of the two steering knuckles;

[0019] Two upper cross arms, which are respectively arranged on both sides of the axle housing; one end of the upper cross arm is rotatably connected to the upper cross arm base, and the other end is rotatably connected to the axle housing;

[0020] Wherein, the two hydraulic motors are installed on the two upper cross arm bases in a one-to-one correspondence.

[0021] Preferably, the independently steerable axle for heavy-load vehicles further comprises:

[0022] a first three-way valve, a first interface of which is connected to the oil outlet of the first motor pump;

[0023] Two four-way solenoid valves are provided in a one-to-one correspondence with the two hydraulic motors, and the first interface and the second interface of the four-way solenoid valve are connected to the first oil circuit and the second oil circuit respectively;

[0024] The third interfaces of the two four-way solenoid valves are connected to the second interface of the first three-way valve and the third interface of the first three-way valve in a one-to-one correspondence; and

[0025] The first interface and the second interface of the second three-way valve are respectively connected to the fourth interfaces of the two four-way solenoid valves in a one-to-one correspondence; the third interface of the second three-way valve is connected to the oil return port of the hydraulic oil tank.

[0026] Preferably, the independently steerable axle for heavy-load vehicles further comprises:

[0027] a third three-way valve, a first interface of which is connected to the oil outlet of the second motor pump;

[0028] Two three-way solenoid valves are arranged in a one-to-one correspondence with the two oil-gas springs; the first interface and the second interface of the three-way solenoid valve are respectively connected to the oil holes of the oil-gas springs and the oil holes of the brake in a one-to-one correspondence; the third interfaces of the two three-way solenoid valves are respectively connected to the second interface of the third three-way valve and the third interface of the third three-way valve in a one-to-one correspondence.

[0029] Preferably, the housing of the hydraulic motor is fixedly mounted on the upper cross arm base by bolts;

[0030] The power output end of the hydraulic motor can rotatably pass through the upper cross arm base and is connected to the steering knuckle through a spline.

[0031] Preferably, one end of the upper cross arm is rotatably connected to the upper cross arm base via a pin, and the other end is rotatably connected to the bridge housing via a pin.

[0032] Preferably, one end of the lower cross arm is connected to the lower end of the steering knuckle through a ball pin, and the other end is connected to the axle housing through a pin shaft.

[0033] Preferably, an oil-gas spring base is provided on the lower cross arm, and the lower end of the oil-gas spring is connected to the oil-gas spring base.

[0034] Preferably, a plurality of bolt holes are provided on the top of the bridge housing for connecting different types of vehicle frames or vehicle bodies.

[0035] The beneficial effects of the present invention are:

[0036] The independently steerable axle for heavy-duty vehicles provided by this invention utilizes two motor pumps to drive multiple oil circuits, enabling the vehicle's steering, braking, and suspension stiffness adjustment functions. When the vehicle encounters road impact, the hydraulic motor closes the hydraulic oil circuit, enabling a self-locking steering mechanism to prevent significant wheel swing caused by the impact. This invention separates the steering mechanism from the actuator, reducing the number of intervening mechanical connections and improving steering precision and stability.

[0037] The independently steerable axle for heavy-loaded vehicles provided by the present invention can independently drive, steer, and brake a single wheel, and is equipped with an independent suspension to achieve complete independence of the wheel angle module; the axle can be connected to different forms of frames or bodies to form different forms of vehicle models, with high versatility; each system has a high degree of integration and a small space occupancy rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the front structure of the independently steerable axle for heavy-load vehicles according to the present invention.

[0039] Figure 2 This is a schematic diagram of the rear structure of the independently steerable axle for heavy-load vehicles according to the present invention.

[0040] Figure 3 This is a schematic diagram of the pipeline connections of the independently steerable axle for heavy-duty vehicles according to the present invention. DETAILED DESCRIPTION

[0041] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0042] like Figure 1-3 As shown, the present invention provides an independently steerable axle for a heavy-loaded vehicle, comprising: a steering knuckle 101, a hydraulic motor 102, an upper cross arm base 103, a bridge housing 200, an upper cross arm 301, an oil-gas spring 302, a lower cross arm 303, a first motor pump 501, a second motor pump 502, a hydraulic oil tank 600, a four-way solenoid valve 700, a first three-way valve 801, a second three-way valve 802, a third three-way valve 803 and a three-way solenoid valve 900.

[0043] The axle housing 200 is a frame structure, installed between two opposing wheels on a heavy-duty vehicle. The first and second motor pumps 501 and 502 are bolted together within the axle housing 200. The hydraulic oil tank 600 is also bolted to the axle housing 200. Wheel angle modules are mounted on the left and right sides of the axle housing 200, corresponding to each wheel. These modules include a steering system, a braking system, a suspension system, and a powertrain. The braking system, powertrain, and wheels within the wheel angle modules are integrated into a wheel-end assembly 400.

[0044] The steering system includes a steering knuckle 101, a hydraulic motor 102 and an upper cross arm base 103. The steering knuckle 101 is connected and fixed to the wheel end assembly 400 by bolts. The upper cross arm base 103 is rotatably mounted on the upper end of the steering knuckle 101, and the hydraulic motor 102 is mounted on the upper cross arm base 103 by bolts. The upper cross arm base 103 is provided with a bearing hole, which is matched with a tapered roller bearing, and the inner ring of the tapered roller bearing is matched with the upper end shaft of the steering knuckle 101. The power output shaft of the hydraulic motor 102 is a spline shaft, which passes through the upper cross arm base 103 and matches the upper end of the steering knuckle 101. The end (lower end) of the spline shaft is provided with a thread, and the spline shaft is axially fixed by installing a nut.

[0045] The suspension system includes an upper cross arm 301, a gas spring 302, and a lower cross arm 303. One end of the upper cross arm 301 is connected to the upper cross arm base 103 via a pin, while the other end is connected to the upper suspension connection point of the axle housing 200 via a pin. One end of the lower cross arm 303 is connected to the lower end of the steering knuckle 101 via a ball stud, secured by a nut that engages the ball stud. The other end of the lower cross arm 303 is connected to the lower suspension connection point of the axle housing 200 via a pin. The lower end of the gas spring 302 is rotatably connected to the gas spring base on the upper side of the lower cross arm 303 via bolts, while the upper end of the gas spring 302 is rotatably connected to the upper shock absorber connection point of the axle housing 200 via bolts.

[0046] Wheel-end assembly 400 integrates a braking system, a powertrain, and a wheel. The powertrain consists of an in-wheel motor installed in the wheel's hub, driving the vehicle. The braking system, consisting of a brake installed in the wheel's hub, includes a brake disc, a brake caliper, a clamping device, and a fixing device.

[0047] The top of the bridge housing 200 is provided with a plurality of bolt holes, which can be connected with different types of vehicle frames to form different types of vehicle models.

[0048] like Figure 3 As shown, the oil inlets of the first motor pump 501 and the second motor pump 502 are respectively connected to the oil outlet of the hydraulic oil tank 600 via oil pipes. The oil outlet of the first motor pump 501 is connected to the first port of the first three-way valve 801. Two four-way solenoid valves 700 are respectively arranged on the left and right sides of the first three-way valve 801. The two four-way solenoid valves 700 are fixed to the bridge housing 200 via bolts and are respectively arranged in a one-to-one correspondence with the two hydraulic motors 102. The hydraulic motor 102 includes a first oil circuit and a second oil circuit. The first and second ports of the four-way solenoid valves 700 corresponding to the hydraulic motor 102 are respectively connected to the first and second oil circuits via oil pipes. The third ports of the two four-way solenoid valves 700 are respectively connected to the second port of the first three-way valve 801 and the third port of the first three-way valve 801. The first and second interfaces of the second three-way valve 802 are connected to the fourth interfaces of the two four-way solenoid valves 700 in a one-to-one correspondence; the third interface of the second three-way valve 802 is connected to the oil return port of the hydraulic oil tank 600 through an oil pipe.

[0049] Among them, when the hydraulic motor 102 takes in oil through the first oil circuit and returns oil through the second oil circuit, the hydraulic motor 102 rotates forward; when the hydraulic motor 102 takes in oil through the second oil circuit and returns oil through the first oil circuit, the hydraulic motor 102 reverses (the forward and reverse rotation here only refers to two opposite rotation directions and does not represent specific steering). The first motor pump 501 drives the oil through the hydraulic valve to drive the hydraulic motor 102 to rotate forward and reverse, thereby driving the steering knuckle 101 to rotate and realize the steering of the wheel in a large forward and reverse angle range. When the vehicle is emergency braked, the emergency braking torque generated by the emergency brake is offset by blocking the oil circuit of the hydraulic motor.

[0050] The first port of the third three-way valve 803 is connected to the oil outlet of the second motor pump 502. The two three-way solenoid valves 900 are provided in a one-to-one correspondence with the two oil-gas springs 302; the first and second ports of the three-way solenoid valves 900 are connected to the oil holes of their corresponding oil-gas springs 302 and the oil holes of the brake, respectively; the third ports of the two three-way solenoid valves 900 are connected to the second port of the third three-way valve 803 and the third port of the third three-way valve 803, respectively.

[0051] The steering system's control process is as follows: the motor pump 500 drives oil through the hydraulic valve to drive the hydraulic motor 102 in both forward and reverse rotations, which in turn drives the steering knuckle 101, enabling the wheels to steer in both directions over a wide range of angles. When the vehicle is in emergency braking, the hydraulic motor's oil circuit is blocked to offset the emergency braking torque.

[0052] In one embodiment, the oil circuit on the left side of the hydraulic motor 102 is defined as a first oil circuit, and the oil circuit on the right side of the hydraulic motor 102 is defined as a second oil circuit.

[0053] When the vehicle turns left, the four-way solenoid valve 700 is controlled to connect the oil pipe connected to the first motor pump 501 and the first oil circuit of the hydraulic motor 102, and the return oil pipe connected to the hydraulic oil tank 600 is connected to the second oil circuit of the hydraulic motor 102; thereby, the two hydraulic motors rotate in the same direction, realizing a left turn.

[0054] When the vehicle turns right, the four-way solenoid valve 700 is controlled to connect the oil pipe connected to the first motor pump 501 and the second oil circuit of the hydraulic motor 102, and the return oil pipe connected to the hydraulic oil tank 600 is connected to the first oil circuit of the hydraulic motor 102; thereby, the two hydraulic motors rotate in the same direction, achieving a right turn.

[0055] During lateral movement, the four-way solenoid valve 700 is controlled to connect the oil inlet pipe connected to the first motor pump 501 with the oil circuits on the inner side (near the axle housing) of the two hydraulic motors 102 (the first oil circuit of one hydraulic motor and the second oil circuit of the other hydraulic motor). Furthermore, the oil return line connected to the hydraulic oil tank 600 is connected with the outer side (near the wheel side) of the hydraulic motors 102 (the second oil circuit of one hydraulic motor and the first oil circuit of the other hydraulic motor). This causes the two hydraulic motors to rotate in opposite directions, rotating the wheels 90° and achieving lateral movement.

[0056] During emergency braking, the oil circuit is closed by controlling the four-way solenoid valve 700 to offset the emergency braking torque generated by the emergency braking.

[0057] The control process of the suspension system and the braking system is as follows:

[0058] (1) When the stiffness of the oil-gas spring 302 needs to be changed, the three-way solenoid valve 900 is controlled to connect the oil pipe connected to the second motor pump 502 and the pipeline connected to the oil-gas spring 302. The second motor pump 502 drives the oil through the third three-way valve 803 and the three-way solenoid valve 900 to the oil-gas chamber of the oil-gas spring 302. By changing the volume of the gas in the oil-gas chamber, the stiffness of the oil-gas spring is changed. When a braking signal is detected, the task of changing the stiffness of the oil-gas spring is interrupted to ensure the priority of braking.

[0059] (2) When a brake signal is detected, the stiffness of the oil-gas spring 302 cannot be changed. By controlling the three-way solenoid valve 700, the oil pipe connected to the second motor pump 502 and the pipeline for delivering the brake are connected. The second motor pump 502 drives the oil to clamp the brake to realize the braking function.

[0060] The independently steerable axle for heavy-loaded vehicles provided by the present invention drives three oil circuits through two motor pumps to realize the vehicle's steering function, braking function, and suspension stiffness adjustment function; each system has a high degree of integration and a small space occupancy rate; a single wheel can be independently driven, steered, and braked, and is equipped with an independent suspension to achieve complete independence of the wheel angle module; the axle can be connected to axles of different types to form different types of vehicle models, and has a high versatility.

[0061] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. An independently steerable axle for a heavy-duty vehicle, characterized in that: include: axle housing; a hydraulic oil tank, which is fixedly arranged in the axle housing; a first motor pump, which is fixedly installed in the axle housing, and an oil inlet of the first motor pump is connected to the hydraulic oil tank; Two hydraulic motors, whose power output ends are respectively connected to the upper ends of the steering knuckles of the wheels on both sides of the axle housing, for driving the steering knuckles to rotate; The hydraulic motor includes a first oil circuit and a second oil circuit; the first oil circuit is selectively connected to the oil outlet of the first motor pump or the hydraulic oil tank, and the second oil circuit is selectively connected to the oil outlet of the first motor pump or the hydraulic oil tank; when the hydraulic motor is supplied with oil through the first oil circuit or the second oil circuit, the rotation direction of the hydraulic motor is different; Two lower cross arms, each provided on either side of the axle housing, one end of each lower cross arm being rotatably connected to the lower end of the steering knuckle, and the other end being rotatably connected to the axle housing; a second motor pump, which is fixedly installed in the axle housing, and an oil inlet of the second motor pump is connected to the hydraulic oil tank; Two oil-gas springs are provided in a one-to-one correspondence with the two lower transverse arms; one end of the oil-gas spring is rotatably connected to the lower transverse arm, and the other end is rotatably connected to the axle housing; Wherein, the oil hole of the oil-gas spring is selectively connected to the oil outlet of the second motor pump; Two brakes are provided corresponding to the wheels on both sides of the axle housing; the oil holes of the brakes are selectively connected to the oil outlet of the second motor pump; a first three-way valve, a first interface of which is connected to the oil outlet of the first motor pump; Two four-way solenoid valves are provided in a one-to-one correspondence with the two hydraulic motors, and the first interface and the second interface of the four-way solenoid valve are connected to the first oil circuit and the second oil circuit respectively; The third interfaces of the two four-way solenoid valves are connected to the second interface of the first three-way valve and the third interface of the first three-way valve in a one-to-one correspondence; and A second three-way valve, wherein the first interface and the second interface are connected to the fourth interfaces of the two four-way solenoid valves in a one-to-one correspondence; the third interface of the second three-way valve is connected to the oil return port of the hydraulic oil tank; a third three-way valve, a first interface of which is connected to the oil outlet of the second motor pump; Two three-way solenoid valves are arranged in a one-to-one correspondence with the two oil-gas springs; the first interface and the second interface of the three-way solenoid valve are respectively connected to the oil holes of the oil-gas springs and the oil holes of the brake in a one-to-one correspondence; the third interfaces of the two three-way solenoid valves are respectively connected to the second interface of the third three-way valve and the third interface of the third three-way valve in a one-to-one correspondence.

2. The independently steerable axle for a heavy-load vehicle according to claim 1, characterized in that: Also includes: Two upper cross arm bases, which are rotatably mounted on the upper ends of the two steering knuckles; Two upper cross arms, which are respectively arranged on both sides of the axle housing; one end of the upper cross arm is rotatably connected to the upper cross arm base, and the other end is rotatably connected to the axle housing; Wherein, the two hydraulic motors are installed on the two upper cross arm bases in a one-to-one correspondence.

3. The independently steerable axle for a heavy-load vehicle according to claim 2, characterized in that: The housing of the hydraulic motor is fixedly mounted on the upper cross arm base by bolts; The power output end of the hydraulic motor can rotatably pass through the upper cross arm base and is connected to the steering knuckle through a spline.

4. The independently steerable axle for a heavy-load vehicle according to claim 3, characterized in that: One end of the upper cross arm is rotatably connected to the upper cross arm base through a pin shaft, and the other end is rotatably connected to the bridge housing through a pin shaft.

5. The independently steerable axle for a heavy-load vehicle according to claim 4, characterized in that: One end of the lower cross arm is connected to the lower end of the steering knuckle through a ball pin, and the other end is connected to the bridge housing through a pin shaft.

6. The independently steerable axle for a heavy-load vehicle according to claim 5, characterized in that: An oil and gas spring base is provided on the lower cross arm, and the lower end of the oil and gas spring is connected to the oil and gas spring base.

7. The independently steerable axle for a heavy-load vehicle according to claim 6, characterized in that: The top of the bridge housing is provided with a plurality of bolt holes for connecting different forms of vehicle frames or vehicle bodies.

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