WO2021093693A1

WO2021093693A1 - Mechanical active suspension mechanism

Info

Publication number: WO2021093693A1
Application number: PCT/CN2020/127347
Authority: WO
Inventors: 石海军
Original assignee: 石海军
Priority date: 2019-11-15
Filing date: 2020-11-07
Publication date: 2021-05-20
Also published as: CN211000824U

Abstract

A vehicle mechanical active suspension mechanism. The upper ends of each damping spring (5) and each shock absorber (6) in a suspension are connected to a worm gear swing arm (7), and then the worm gear swing arm is connected to a vehicle body by means of a worm-and-gear mechanism. An ECU controls a servo motor (9) to drive each worm (8) to rotate so as to drive the worm gear swing arm (7) and the suspension connected thereto to generate a lifting motion relative to the vehicle body, thereby realizing the height adjustment of the vehicle suspension. A lever member (12) is used to adjust a fulcrum of an upper wishbone (4) of a transverse double wishbone suspension relative to the vehicle body, thereby solving the problem of excessive wheel inclination change during the lifting of the suspension; a novel four-bar Y-shaped longitudinal swing arm is employed to improve the supporting performance of the suspension; a braking mechanism is provided in the middle of an anti-roll bar, and the disconnected anti-roll bars are combined by a dog clutch (18), thereby overcoming defects of anti-roll bars in conventional suspensions and further improving performance thereof.

Description

A mechanical active suspension mechanism

Technical field

The invention relates to a vehicle suspension mechanism, in particular to a mechanical active suspension mechanism.

Background technique

The ideal vehicle suspension system should: When the vehicle is driving on bumpy roads or off-road roads, the chassis should be taller and the suspension should be softer to improve the passability and comfort of the vehicle; when the vehicle is on a paved road , When driving at high speed on high-speed roads, the chassis is required to be lower and the suspension to be harder to improve the stability and handling of the vehicle. Under the traditional chassis technology, controllability and comfort are a natural contradiction. Generally, they can only be tuned to one side. Designers try their best to find the balance between the two. In the traditional mechanical suspension Among them, the appearance of anti-roll bar (also known as stabilizer bar) makes it have a better solution. The anti-roll bar is equivalent to adding a U-shaped torsion bar spring to the suspension. When the left and right suspensions are compressed or extended at the same time, the anti-roll bar does not work; when the vehicle turns, the outer suspension is Compression, the inner suspension is stretched, and the anti-roll bar will play a role at this time to prevent the compression of the outer suspension and the extension of the inner suspension, thereby reducing the roll of the vehicle when turning, and keeping the suspension better At the same time as the comfort, its handling is also better. However, the current anti-roll bar has many limitations. When the vehicle is driving on potholes and bumpy roads, the anti-roll bar will reduce the comfort of the vehicle. When off-road, it will affect the extension and contraction of the suspension, and it is easy to make one wheel hang in the air. , Thereby affecting its passability. Therefore, an active suspension with high energy and low energy, soft and hard performance will naturally be more popular. Currently, there are three widely used active suspension systems: air suspension, hydraulic suspension, and electromagnetic suspension.

The air suspension is composed of air springs, adjustable shock absorbers, air pumps, etc. It has the ability to adjust the height of the chassis and change the softness and hardness of the suspension. It can be adjusted to the best state according to needs. It has good applicability and is currently the most widely used initiative Suspension form. The chassis height adjustment is mainly determined by the length of the air spring, so the adjustment range is not large. At the same time, because the structure of the air suspension is more complicated, it is expensive and has a higher failure rate. It will cause the air pump to overheat during frequent use. Life span, air springs generally need to be replaced within 60,000-80,000 kilometers, and subsequent maintenance costs are high.

Each wheel of the hydraulic suspension has a hydraulic sub-cylinder, which can adjust the height and hardness of the suspension by adjusting the oil filling amount of the cylinder and the size of the damping valve. Compared with air suspension, hydraulic suspension has strong load capacity, small size and convenient layout. The disadvantage is that the response speed is slow, the adjustment range is narrow, and the problem that it needs to be replaced after a certain number of kilometers still exists, and the hydraulic pump will consume a part of the power.

The electromagnetic suspension controls the viscosity of the electromagnetic fluid in the shock absorber by adjusting the current, so that the damping is changed, thereby adjusting the softness and hardness of the shock absorber. It is characterized by fast response speed and high safety. However, the height of the chassis cannot be adjusted, and only the shock absorbers can be used to adjust the hardness of the suspension, which is regarded as a semi-active suspension.

The current active suspension system is only used in some luxury cars because of the high cost and low cost performance. Therefore, there is an urgent need for a suspension system that is cheap, durable, low maintenance cost, and can meet the functional requirements of the active suspension to meet the consumer needs of the masses.

Summary of the invention

The purpose of the present invention is to solve the problems of high price of the current active suspension system, non-durable structure, high maintenance cost in later period, and suspension parameter changes caused by the height adjustment of the chassis and the rigid and single function of the U-shaped anti-roll bar.

In order to solve the above problems, the present invention provides a mechanical active suspension mechanism, in which the support spring and the upper end of the shock absorber are connected to one end of a worm gear swing arm in which a swing arm is integrated with the worm wheel, and the other end of the worm gear swing arm is connected to the vehicle body Articulated, the worm gear swing arm maintains a certain positional relationship with the body through a worm mechanism that is coupled with the worm gear. The servo motor controlled by the ECU drives the worm to rotate through a deceleration mechanism to drive the worm gear swing arm to swing up and down, so that the suspension swing arm swings together , Realize the height adjustment of the vehicle chassis.

In the currently commonly used horizontal unequal-length double wishbone suspension, the connecting end of the upper wishbone and the car body is connected to the car body through a lever member, the middle support point of the lever member is connected to the car body, and the end close to the car body is connected to the upper wishbone. The outer end is connected with the worm gear swing arm through a connecting rod. When the suspension swing arm is in the horizontal position, the lever is also in the horizontal position. When the worm gear swing arm swings to adjust the height of the chassis, the lever rotates accordingly. On the foundation, push the upper fork arm to a certain position to compensate for the change of the wheel camber caused by the suspension height adjustment, so that it is always within an allowable range.

In the longitudinal configuration of the worm gear swing arm, the front suspension adopts a longitudinal, equal length, double four-bar fork-shaped swing arm. The basic structure of the four-bar fork-shaped swing arm is that the first two rods are connected to form a fork at one end. The other end of the rod is connected with the car body to form a triangular structure. One end of the latter two rods is connected into a fork shape and connected to the steering knuckle. The other end of the two rods is connected to the fork structure formed by the first two rods to form a second triangular structure. . Because of the parallelogram principle of the equal-length double trailing arms, when the suspension height is adjusted, the front wheel camber angle, caster angle, wheelbase and other parameters always remain unchanged; the four-bar fork-shaped swing arm makes the suspension horizontal or It is very supportive longitudinally. The rear suspension adopts a longitudinal single four-bar fork-shaped swing arm. The basic structure of the four-bar fork-shaped swing arm is that the four rods are connected into two forks, which are arranged up and down, and the two cross ends are connected by the axle seat. As a whole, the connecting end of the body is merged into one end to become a single swing arm. This kind of swing arm, as an independent rear suspension swing arm, has very good support in the lateral and longitudinal directions, and will not change the track and inclination when the suspension height is adjusted.

A brake mechanism composed of a brake disc and a brake caliper is set in the middle of the U-shaped anti-roll bar in the suspension. The brake disc is fixedly connected to the anti-roll bar, and the brake caliper is connected to the body, which is completed under the control of ECU Release and clamp the brake disc. When the vehicle is braking, the brake disc is clamped, and the anti-roll bar can be used to reduce the nodding action of the vehicle. When the vehicle is running at high speed, clamping the brake disc can harden the suspension and enhance the vehicle's road feedback performance.

The U-shaped anti-roll bar, which is separated from the middle into the left and right parts, is combined by a jaw clutch. One half of the clutch is connected to the brake disc and fixedly connected to one side of the anti-roll bar. The other half of the clutch is connected with the brake disc. The anti-roll bar on the other side adopts spline connection, which can slide left and right, and complete the separation action of the clutch under the action of the separation mechanism. The tooth shape of the clutch adopts rectangular teeth, and the top of the teeth is chamfered into a bevel. The movable half of the clutch consists of a The compression spring presses it to the other half of the clutch. After the release mechanism is released, the clutch is automatically engaged under the force of the spring. When the vehicle is driving on bumpy potholes or off-road roads, the clutch is disengaged and the anti-roll bar fails, which does not affect the comfort and passability of the vehicle.

The surface of the brake disc in the middle of the anti-roll bar is a concave-convex surface with a certain tooth shape, so that the brake disc will not slip when it is clamped. The brake disc can adopt a fan-shaped structure to reduce the volume.

The beneficial effects of the present invention:

(1) The present invention uses a worm gear mechanism to drive a worm gear arm supporting a shock absorber spring to swing up and down to achieve the height adjustment of the suspension on the basis of the traditional spiral spring suspension, because it is a purely mechanical suspension. The structure is more stable and durable than the air suspension, with a longer life span, and can be used for life. The manufacturing cost of traditional mechanical components such as spiral springs and worm gears is also lower.

(2) The lifting height of the chassis in the present invention depends on the length and swing angle of the worm gear swing arm connected with the spiral spring, and has nothing to do with the spring height. Therefore, compared with an air suspension, the suspension chassis of the present invention has a larger lifting range, and can freely switch between the chassis height of the off-road vehicle and the chassis height of the sports car.

(3) The present invention uses a servo motor as a drive unit. Compared with the air pump and hydraulic pump in the air suspension and hydraulic suspension, the technology is mature and the structure is simple, the response is faster, and the control is more accurate.

(4) The worm gear mechanism used in the present invention has good self-locking characteristics. The servo motor only does work when the suspension needs to be adjusted, and no more work is needed after the adjustment is in place, so the suspension system consumes less energy.

(5) The present invention uses a lever to adjust the connection position of a fork arm of the double wishbone suspension relative to the vehicle body, which solves the problem that the wheel inclination angle changes greatly when the double wishbone suspension is adjusted in a large range.

(6) In the servo motor drive mechanism used in the present invention, the encoder of the servo motor can enable the trip computer to grasp the high and low positions of each suspension, thereby accurately judging the body posture and reducing the number of sensors. When the vehicle turns and brakes, air suspension, hydraulic suspension and electromagnetic suspension all improve the stiffness of springs or shock absorbers to reduce the body's roll when turning and the nodding action when braking. The present invention can raise the outer suspension and lower the inner suspension when the vehicle is turning, according to the data of various sensors; when the vehicle is braking, raise the two front wheel suspensions to completely offset the camber and braking of the vehicle when turning. The momentary nodding action makes the body more stable and comfortable.

(7) The vertical four-bar fork-shaped swing arm used in the present invention can satisfy the wide-range height adjustment of the suspension without changing the track and inclination angle, and has good support performance in the longitudinal and transverse directions. It is also an engine compartment. Make more space.

(8) The present invention utilizes the torsion bar spring principle of the U-shaped anti-roll bar to improve the braking stability of the vehicle, change the hardness of the suspension, and improve the vehicle performance with low cost.

(9) The anti-roll bar of the present invention has simple and convenient disconnection operation, simple and durable structure, avoids the shortcomings of the anti-roll bar, and makes its performance more outstanding.

Compared with the existing active suspension system, the mechanical active suspension mechanism of the present invention has a more stable and durable structure, lower cost, more accurate control, and more comprehensive functions.

Description of the drawings

Fig. 1 is a three-dimensional schematic diagram of a horizontally unequal-length double wishbone suspension according to the present invention.

Fig. 2 is a three-dimensional schematic diagram of an embodiment of an equal-length double four-bar fork-shaped trailing arm front suspension according to the present invention.

Fig. 3 is a three-dimensional schematic diagram of an embodiment of a four-bar fork-shaped single trailing arm rear suspension according to the present invention.

Fig. 4 is a schematic diagram of a structural example of a four-bar fork-shaped swing arm part of a longitudinal front suspension implemented according to the present invention.

Fig. 5 is a three-dimensional schematic diagram of an embodiment of a four-bar fork-shaped swing arm used in a longitudinal rear suspension implemented according to the present invention.

Fig. 6 is a three-dimensional schematic diagram of an embodiment of the brake and clutch component in the middle of the anti-roll bar implemented according to the present invention.

Fig. 7 is a three-dimensional schematic diagram of the disengaged state of the anti-roll bar clutch implemented according to the present invention.

Fig. 8 is a schematic diagram of the position change of the lever member implemented according to the present invention as the worm gear swing arm rotates up and down.

The part numbers mentioned in the drawings: 1. Frame; 2. Lower wishbone; 3. Steering knuckle; 4. Upper wishbone; 5. Damping spring; 6. Shock absorber; 7. Worm gear swing arm; 8. Worm; 9, servo motor; 10, reduction pinion; 11, reduction gear; 12, lever parts; 13, connecting rod; 14, left anti-roll bar; 15, right anti-roll bar; 16, anti-roll bar pull rod; 17. Brake disc; 18. Clutch; 19. Compression spring; 20. Clutch release fork; 21. Brake caliper; 22. Front suspension four-bar fork lower swing arm; 23. Front suspension four-bar fork Upper swing arm; 24. Four-bar fork-shaped swing arm of rear suspension; 25. Pull line.

Detailed ways

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In the entire manual, the same reference numerals represent the parts of the same type with the same name, and the same reference numerals and descriptions will be omitted for the similar parts in the left-right symmetrical mechanism. The accompanying drawings are only for better describing the concept of the present invention, and the understanding of the concept of the present invention is not limited to the accompanying drawings.

1. The height adjustment of the suspension.

As shown in Figs. 1 and 2, Fig. 1 is an embodiment of a unequal-length double wishbone front suspension, and Fig. 2 is an embodiment of a longitudinal equal-length double wishbone front suspension. The damping spring 5 and the upper end of the shock absorber 6 are connected with the worm gear swing arm 7, and the other end of the worm gear swing arm 7 is hinged with the frame 1. Since the rotation range of the worm wheel does not need to be large, only a part of the worm wheel is taken. The worm 8 is connected to the frame 1, because the worm gear mechanism has good self-locking performance when the torque is transmitted from the worm gear to the worm, so the worm gear swing arm is equivalent to the fixing mechanism of the frame. When the ECU controls the rotation of the servo motor 9, the power is transmitted to the worm 8 through the reduction pinion 10 and the reduction gear 11, and the worm 8 rotates, driving the worm gear arm 7 to swing up and down, and the worm gear arm 7 passes through the shock absorber 6 and the shock-absorbing spring 5 Drive the entire suspension to swing up and down to realize the height adjustment of the suspension.

2. Compensation for the wheel inclination of the horizontally unequal-length double wishbone suspension.

The current double-wishbone suspensions are basically double-wishbone mechanisms with unequal lengths with a lower length and a shorter upper. Assuming that the upper and lower swing arms are in a horizontal position, the camber angle of the wheel at this time is a normal value. Short, so when the suspension swings up or down, the upper end of the wheel will tilt inward, thereby changing the camber angle of the wheel.

As shown in Figures 1 and 8, in the present invention, one end of the upper fork arm 4 close to the center of the frame is connected to one end of the lever member 12, the middle fulcrum of the lever member 12 is connected to the frame 1, and the other end is connected to the connecting rod 13. Connected, the connecting rod 13 is connected with the worm gear swing arm 7. When the upper and lower fork arms 2, 4 are in the horizontal position, the lever member 12 is also in the horizontal position, and the connecting end of the lever member 12 and the upper fork arm 4 is at the end close to the center of the frame , The camber angle at this time is the normal value. When the worm gear swing arm 7 swings up and down to adjust the height of the suspension, the lever member 12 is driven to rotate to a certain position through the connecting rod 13, and the lever member 12 will push the upper fork arm 4 outward for a certain distance to compensate for the inward tilt angle of the upper end of the wheel . By selecting appropriate parameters for the connecting position of the lever and the worm gear swing arm and the connecting rod, the camber angle of the wheel can always be within an allowable range within the height adjustment range of the suspension.

3. The swing arm structure of the longitudinally arranged double four-bar fork-shaped front suspension.

Due to the parallelogram principle, the equal-length double-swing arm front suspension maintains the same parameters as the wheel inclination angle and wheel track during the suspension height adjustment process, and can have more space than the horizontal double-wishbone suspension. The engine compartment space is more suitable for adjustable suspension. Due to the influence of the front wheel steering, the present invention adopts a double four-bar fork-shaped swing arm.

As shown in Fig. 2 and Fig. 4, Fig. 2 is a three-dimensional structural diagram of an embodiment of the four-bar fork-shaped double trailing arm front suspension with equal length implemented in the present invention. The principle of height adjustment of the suspension is the same as the principle of height adjustment of the suspension shown in FIG. 1. Fig. 4 is a schematic diagram of the structure of the front double four-bar fork-shaped swing arm. In Figure 4, rod a and rod b cross into a fork shape, which can form a triangle structure with the frame 1. The rod c and rod d cross into a fork shape, and are connected to the fork formed by rods a and b to form a second A triangular structure, this structure makes it have better support performance in both the horizontal and vertical directions.

4. The swing arm structure of the longitudinal four-bar fork-shaped rear suspension.

As shown in Figure 3 and Figure 5, in Figure 5, rod a and rod b are connected into a fork shape, rod c and rod d are connected into a fork shape, and are arranged up and down. The cross end is connected by the axle seat e part to form a whole , The upper and lower two forks at the other end are combined into one end to form a single-wishbone structure. The swing arm of this structure is used as an independent rear suspension swing arm, which not only facilitates the height adjustment of the suspension, but also has good support performance in both the longitudinal and lateral directions.

5. Combination of control and separation of anti-roll bar.

As shown in Figures 6 and 7, the brake disc 17 combined with one half of the clutch is fixedly connected to the left anti-roll bar 14, the brake caliper 21 is connected to the frame 1, and the other half of the clutch 18 is connected to the right anti-roll bar 14. The tilt bar 15 is connected together by splines and can move axially along the splines. When the cable 25 is released, the clutch 18 is pressed to the left under the action of the compression spring 19. At this time, the clutch is combined, and the left and right anti-roll bars 14, 15 are equivalent to a complete anti-roll bar, so that the car can maintain a more comfortable The soft suspension also has better turning and anti-tilting ability. When the car is braking, the brake caliper 21 clamps the brake disc 17, which is equivalent to adding a torsion bar spring to the front suspension to harden the suspension, thereby reducing the nodding action of the car's brakes. When the car is moving at a high speed, clamping the brake disc 17 can make the suspension rigid, thereby improving the vehicle handling and road surface feedback capabilities.

When the vehicle is driving on bumpy roads, the anti-roll bar will affect the comfort of the vehicle. When driving on off-road roads, the anti-roll bar will limit the expansion and contraction of the suspension, which will easily cause the wheels to hang in the air and affect the passability. At this time, it is only necessary to tighten the cable 25, and the clutch release fork 20 can shift the clutch 18 to the right to disconnect the left and right anti-roll bars, as shown in FIG. 7.

After the vehicle reaches a level road, the cable 25 is released, and the clutch is restored to the connected state under the action of the compression spring 19. The chamfering of the crest of the clutch into a bevel can ensure that it enters the correct joint position.

6. Active control of suspension.

Each suspension is controlled by an independent servo motor. Therefore, when the vehicle is turning, the outer suspension can be adjusted to increase, the inner suspension can be lowered, and the height of the front and rear suspension can be adjusted at high speed. The encoder of the servo motor can be adjusted. Real-time feedback of the position of each worm gear swing arm is very convenient for the traveling computer to control the suspension posture.

The above are only the embodiments of the present invention, so the scope of implementation of the present invention cannot be limited by this.

Claims

A mechanical active suspension mechanism, which is characterized in that the upper end of the shock absorber spring and the shock absorber in the automobile suspension is connected to one end of a worm gear swing arm whose swing arm is integrated with the worm wheel, and the other end of the worm gear swing arm is hinged with the vehicle body , The worm gear arm is fixed in position with the body through the worm mechanism matched with the worm gear. The servo motor controlled by the ECU drives the worm to rotate through a deceleration mechanism to drive the worm gear arm to swing up and down; the worm gear arm in the suspension can be horizontally and obliquely Or longitudinally arranged. In a horizontally unequal-length double wishbone suspension, the upper wishbone and the body are connected to the body through a lever piece, the middle support point of the lever piece is connected to the body, one end is connected to the upper wishbone, and the other end It is connected with the worm wheel swing arm through a connecting rod; when the worm wheel swing arm is set longitudinally, the front suspension adopts a longitudinal, equal-length, double four-bar swing arm structure, and the rear suspension adopts a longitudinal single four-bar fork Shaped swing arm structure.
The mechanical active suspension mechanism according to claim 1, characterized in that: in a horizontally unequal-length double wishbone suspension, the installation position of the lever member is such that when the lever member is in a horizontal position, the suspension The upper and lower swing arms are also in a horizontal position, the connecting point between the lever member and the upper swing arm is at the inner end close to the center of the frame, and the connecting point between the lever member and the connecting rod is at the outer end.
A mechanical active suspension mechanism according to claim 1, characterized in that: in the longitudinally placed swing arm front suspension, the basic structure of the four-bar fork-shaped swing arm is that the first two rods are connected at one end into a fork shape , The other end is connected with the car body to form a triangle structure; one end of the latter two rods is connected into a fork shape and connected with the steering knuckle, and the other end of the two rods is connected with the fork structure formed by the first two rods to form a second triangle structure.
A mechanical active suspension mechanism according to claim 1, characterized in that: in the rear suspension of the longitudinally placed swing arm, the basic structure of the four-bar fork-shaped swing arm is that four rods are connected to form two forks. The two cross ends are connected by the axle seat into a whole, and the other ends of the two forks are merged together to form a single swing arm.
A mechanical active suspension mechanism, characterized in that: a brake mechanism composed of a brake disc and a brake caliper is arranged in the middle of the U-shaped anti-roll bar in the suspension, and the brake disc is fixed with the anti-roll bar Connection, the brake caliper is connected to the body, and the brake caliper completes the loosening and clamping action of the brake disc under the control of the ECU.
A mechanical active suspension mechanism according to claim 5, characterized in that: the U-shaped anti-roll bar, which is separated from the middle brake disc of the anti-roll bar, into left and right parts, is joined by a jaw clutch. At the same time, half of the clutch is integrated with the brake disc and fixedly connected with one side of the anti-roll bar; the other half of the clutch is connected with the other side of the anti-roll bar by spline connection, and can slide left and right, in the clutch release mechanism The clutch is released under the action.
A mechanical active suspension mechanism according to claim 5, characterized in that: the tooth shape of the jaw clutch connecting the brake disc and the anti-roll bar is rectangular or trapezoidal, and the top of the tooth is chamfered into a bevel, The movable half of the clutch is pressed by a compression spring to the other half of the clutch. After the release mechanism is released, the clutch is automatically connected under the force of the spring.
A mechanical active suspension mechanism according to claim 5, wherein the surface of the brake disc in the middle of the anti-roll bar is a concave-convex surface with a certain tooth shape.