JP6187744B2 - Suspension device - Google Patents

Description

  The present invention relates to a suspension device that can vary torsional rigidity.

In popular vehicles (vehicles), a torsion beam type suspension device is often used for the rear suspension because of its simple structure.
This suspension device has a structure that employs a trailing arm member that supports left and right wheels (wheels on both sides in the vehicle width direction) and a torsion beam member that connects the trailing arm members. A characteristic of this suspension device is that the torsion beam member is twisted by a torsional force generated between the left and right wheels when the vehicle body rolls, for example, by turning during traveling. By the return of the torsion beam member, the roll during turning can be suppressed. That is, the anti-roll effect is secured by the torsion beam member.

By the way, it is desirable to set the torsional rigidity of the torsion beam member low if importance is attached to the riding comfort of the vehicle, and it is desirable to set it high if importance is attached to steering stability during turning (roll amount suppression).
However, since the torsion beam type relies on the torsional rigidity of the torsion beam member, it is difficult to achieve both riding comfort and handling stability. In order to increase roll rigidity, a hollow bar is mounted in the torsion beam, but it has not yet achieved both ride comfort and handling stability.

  Therefore, in the suspension type, a technique as disclosed in Patent Document 1 has been proposed in order to achieve both. This is because a torsion bar member divided into two is provided in the torsion beam, and the split torsion bar member is provided with a clutch mechanism that opens and closes by the behavior of a lateral link. This is a technique that “breaks” the bar members (lateral link: no input), and “contacts” the divided torsion bar members with the input from the lateral link when turning.

JP-A-8-2227

However, the technology listed in Patent Document 1 can set only two types, a mode in which the torsional rigidity of the torsion beam member is exhibited and a mode in which the torsional rigidity of both the torsion beam member and the torsion bar member are exhibited. Comfort and handling stability are not guaranteed.
That is, the required riding comfort and steering stability of the vehicle are different depending on the driving state of various vehicles, for example, general road driving, high-speed driving, and the like, as well as a steep steering wheel and additional steering during steering. Therefore, it is desirable that the suspension device ensure torsional rigidity that can cope with such a traveling state. However, since Patent Document 1 merely “cuts” and “contacts” between the torsion bar members, it does not reach the setting of torsional rigidity according to various traveling states. For this reason, with this structure, it is difficult to achieve both sufficient ride comfort and steering stability.

  Accordingly, an object of the present invention is to provide a suspension device that can set torsional rigidity in accordance with various driving states of a vehicle.

The invention according to claim 1 is a suspension device for a vehicle, comprising a pair of trailing arm members that support the wheels on both sides in the vehicle width direction of the vehicle, a torsion beam member that connects between the trailing arms, and trailing A torsion bar member that is provided along the arm and receives a torsional force generated between the wheels, a torsion amount control mechanism that controls a torsion amount of the torsion bar member, a torsion bar member and a torsion amount control mechanism; A torsion amount control mechanism for setting the torsional rigidity of the entire suspension device, and the torsion amount control mechanism includes a first torsion amount in which the restraining force for restraining the torsion bar member is continuously variable according to the turning condition of the vehicle. The adjustment mechanism and the torsion bar member in the direction opposite to the twisting direction of the torsion bar member when there is additional steering during the steering of the vehicle A second torsion amount adjusting mechanism for applying a load was assumed to have a.

According to the first aspect of the invention, the torsional rigidity of the suspension device can be set in various ways by controlling the torsion amount of the torsion bar member.
Therefore, the torsion beam type suspension device can set torsional rigidity according to various driving states of the vehicle. For this reason, not only the ride comfort of the vehicle but also steering stability (roll amount suppression) suitable for the same driving state during turning in various driving states can be ensured.

In addition, the torsional rigidity of the suspension device can be set in a wide range with a simple structure.

The perspective view which shows the suspension apparatus which concerns on one Embodiment of this invention. Sectional drawing which follows the AA line in FIG. 1 which shows the torsion amount control mechanism integrated in the apparatus.

Hereinafter, the present invention will be described based on an embodiment shown in FIGS. 1 and 2.
FIG. 1 shows the rear side of a vehicle to which the present invention is applied. 1, reference numeral 1 denotes a vehicle body (illustrated by a two-dot chain line), 2a and 2b, rear wheels (illustrated by a two-dot chain line) arranged on the left and right sides (both sides in the vehicle width direction) of the rear of the vehicle body 1, and 3 The suspension devices provided at the rear are respectively shown.
The suspension device 3 is a torsion beam type, here, an H-type torsion beam type suspension device. The suspension device 3 will be described. Reference numerals 5a and 5b denote a pair of left and right trailing arm members. Each of the trailing arm members 5a and 5b has an eyeball portion 6a serving as a vehicle body support portion at one end portion, and a hub portion 6b serving as a wheel mounting portion at the other end portion. The eyeball portions 6a of the trailing arm members 5a and 5b are both supported by the vehicle body 1 via bushes (both not shown), and the hub portion 6b side extends to the rear. Thus, the trailing arm members 5a and 5b are supported on the vehicle body 1 so as to be swingable in the vertical direction. The rear wheels 2a and 2b are mounted on the hub portions 6b of the arm members 5a and 5b.

  The left and right trailing arm members 5a and 5b are connected by a torsion beam member 8 extending in the vehicle width direction, thereby forming an H-shaped arm structure. The torsion beam member 8 is a member that receives a torsional force generated between the rear wheels 2a and 2b. For example, a U-shaped beam member having a lower open side is used. Incidentally, the torsion beam member 8 is formed of a member having low torsional rigidity in order to attach importance to riding comfort. Although not shown, a spring member, a shock absorber, or the like is assembled to the trailing arm members 5a and 5b.

  Between the trailing arm members 5a and 5b, there is provided a variable stiffness device 10 that can set the torsional rigidity of the suspension device 3 in a wide range. The variable stiffness device 10 includes a torsion bar member 11 provided between the trailing arm members 5a and 5b, and a control unit 12 (corresponding to the torsion amount control mechanism of the present application) for controlling the torsion amount of the torsion bar member 11. It is configured.

  In other words, the torsion bar member 11 is, for example, a steel pipe member that can be torsionally deformed along the vehicle width direction. The pipe member is accommodated in the torsion beam member 8 along the beam member 8, and one end portion is fixed to one end portion (one end side) of the torsion beam member 8 via the bracket member 14. The other end portion of the pipe member is connected to the control unit 12 installed in the other end portion (the other end side) of the torsion beam member 8. Thus, the torsion bar member 11 is arranged between the trailing arm members 5a and 5b, and the torsion force generated between the rear wheels 2a and 2b is also input to the torsion bar member 11.

  As shown in the cross-sectional view of FIG. 2 (A-A line in FIG. 1), the control unit 12 continuously adjusts the amount of torsion adjustment 16 that restricts the other end of the torsion bar member 11. Equivalent to the first torsion amount adjusting mechanism of the present application) or the torsion amount adjusting mechanism 17 for applying a load in the direction opposite to the torsion direction of the torsion bar member 11, that is, the rotational displacement in the opposite direction (the second torsion amount adjustment of the present application). The structure is equivalent to the mechanism). That is, this embodiment employs a structure in which two types of twist amount adjusting mechanisms 16 and 17 are used in combination.

  When each part of the control unit 12 is described with reference to FIG. 2, reference numeral 19 denotes a casing of the control unit 12 (illustrated by a one-dot chain line). The casing 19 is installed in the torsion beam member 8 (fixed). A relay shaft 20 is rotatably supported on the wall portion of the casing 19 on the torsion bar member 11 side. The relay shaft 20 and the torsion bar member 11 are connected in series via a coupler 21.

In the casing 19, the torsion amount adjusting mechanism 16 and the torsion amount adjusting mechanism 17 are housed in this order from the relay shaft 20 side. Of these, the torsion amount adjusting mechanism 16 has a structure using, for example, an electromagnetic clutch 16a.
That is, the electromagnetic clutch 16 a is formed with a structure in which, for example, an armature member 22 is provided on the outer peripheral portion of the relay shaft 20, and an exciting coil 23 is provided around the armature member 22. That is, the torsion bar member 11 can be freely held by the exciting force generated by the electromagnetic clutch 16a. Here, in the electromagnetic clutch 16a, the binding force (holding force) of the torsion bar member 11 is changed from “0%” at which the torsion bar member 11 is in a free rotation state in response to energization to the excitation coil 23. A device that can be continuously changed to “100%” at which the member 11 is in a rigid state is used. The amount of torsion of the torsion bar member 11 can be varied in a wide range (100% to 0%) by varying (0% to 100%) the restraining force (holding force) of the torsion bar member 11 by the electromagnetic clutch 16a. That is, the torsion amount of the torsion bar member 11 can be continuously changed.

For the torsion amount adjusting mechanism 17, for example, a structure is used in which the torsion bar member 11 is rotationally displaced in the direction opposite to the torsion direction of the torsion bar member 11 by the axial torque of the electric motor 25. For example, the torsion amount adjusting mechanism 17 is a gear mechanism that relays between the output shaft 25 a of the electric motor 25 and the end of the relay shaft 20, for example, an output gear 26 provided on the output shaft 25 a of the electric motor 25, and the output gear 26. The gear mechanism 30 having a driven gear 28 that transmits to the relay gear 27 and the input gear 29 at the end of the relay shaft 20 that meshes with the relay gear 27, and the output of the driven gear 28 are “disconnected” and “contact” ( A structure having a clutch portion 32 that opens and closes and an angle sensor 33 that detects the amount of displacement transmitted to the torsion bar member 11 is used. Thus, when the shaft torque of the electric motor 25 is transmitted to the input gear 29 via the output gear 26, the driven gear 28 and the relay gear 27, the torsion bar member 11 is in a direction opposite to the torsion direction of the torsion bar member 11. It is displaced to turn. The angle sensor 33 and the clutch portion 32 are provided to detect the amount of displacement input to the torsion bar member 11. As a result, axial torque is continuously applied in the direction in which the torsion bar member 11 returns (roll rigidity: increased). In other words, the suspension device 3 is configured so that the torsion amount of the torsion bar member 11 can be continuously changed. The suspension device 3 has a mechanism for continuously reducing the restraining force (holding force) of the torsion bar member 11 and the torsion bar member 11. Various torsional stiffnesses can be set in combination with a mechanism that continuously increases roll stiffness. In particular, the electromagnetic clutch 16a, the electric motor 25, the clutch unit 32, and the angle sensor 33 are configured by a control unit 35 (for example, a microcomputer) mounted on the vehicle body 1 so that torsional rigidity suitable for various driving conditions of the vehicle is ensured. Driving state signals input to the control unit 35, such as steering angle signals, steering speed / acceleration signals, vehicle speed signals, yaw / roll / pitching rate signals, yaw acceleration ratio signals, front / rear left / right G signals, rolls Based on the acceleration ratio signal, the follow-up steering signal, the shared load detection, the air pressure sensor, and the like, the torsional rigidity of the suspension device 3 is appropriately set. In addition, using navigation, smartphones, safe driving support systems [DSSS: Driving Safety Support Systems (systems that use VICS (registered trademark) and optical beacons to transmit intersection information to traveling vehicles)], inter-vehicle communication systems, etc. It is also possible to obtain and control information before steering.

The torsional rigidity of the suspension device 3 will be described. When the vehicle travels straight on a general road, the electromagnetic clutch 16 is not excited. That is, the torsion bar member 11 is in an unloaded state. As a result, the torsional rigidity of the suspension device 3 can only be obtained with the low rigidity of the torsion beam member 8, thereby providing a high ride comfort.
When the vehicle turns (steers), the torsion bar member 11 is rigidly connected according to the excitation of the electromagnetic clutch 16a. Thereby, the torsional rigidity of the suspension device 3 is a rigidity obtained by adding the rigidity of the torsion bar member 11 to the rigidity of the torsion beam member 8. At this time, the exciting force of the electromagnetic clutch 16a varies according to the degree of turning. Then, the force (holding force) that restrains the end of the torsion bar member 11 changes, and the torsion amount of the torsion bar member 11 changes according to the turning condition. Thus, the roll rigidity of the suspension device 3 is adjusted according to the turning condition. Thereby, the steering stability (roll amount suppression) according to the turning (steering) state of the vehicle is ensured.

The roll rigidity of the suspension device 3 varies depending on the vehicle speed, and high riding comfort and high steering stability are ensured even when traveling on a highway.
Further, when additional steering or a sudden handle operation is performed during steering of the vehicle, the torsion bar member 11 is rotationally displaced in the direction opposite to the torsional direction by the operation of the electric motor 25. That is, a load is forcibly applied in the reverse direction. Thereby, the force in the returning direction of the torsion beam member 11 increases. That is, the roll rigidity of the suspension device 3 is adjusted to a rigidity exceeding that in the state where the torsion beam member 8 and the torsion bar member 11 are rigidly connected. Thereby, at the time of additional steering or a sudden steering operation, a large roll rigidity is ensured and high steering stability is ensured.

The suspension device 3 can set the torsional rigidity according to the various driving states of the vehicle by changing the torsion amount of the torsion bar member 11.
Therefore, the suspension device 3 can ensure the riding comfort and steering stability suitable for the driving state at the time of various turns as well as the riding comfort of the vehicle when traveling straight ahead.
When the torsion amount adjusting mechanism 16 for changing the restraining force of the torsion bar member 11 and the torsion amount adjusting mechanism 17 for applying a load in the direction opposite to the torsion direction of the torsion bar member 11 are used, the torsion of the suspension device 3 can be simplified. Rigidity can be set in a wide range.

Note that the present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the spirit of the present invention.
For example, in one embodiment, an example in which both the torsion amount adjusting mechanism 16 and the torsion amount adjusting mechanism 17 are used has been described. However, the present invention is not limited to this. Produces the same effect. Further, as the torsion amount adjusting mechanism 16, a structure using an electromagnetic clutch is given as an example, and as the torsion amount adjusting mechanism 17, a structure using an electric motor or a gear mechanism is given as an example. However, the structure is not limited thereto. A mechanism using other equipment may be used. In one embodiment, the torsion amount of the torsion bar member 11 is controlled via the relay shaft 20. However, the present invention is not limited to this, and the torsion amount of the torsion bar member 11 may be directly controlled without using the relay shaft 20. Good. Of course, the present invention may be applied to other types of rigid suspension devices.

2a Rear wheel (wheel)
3 Suspension device 5a, 5b Trailing arm member 8 Torsion beam member 11 Torsion bar member 12 Control unit (torsion amount control mechanism)
16 Twist amount adjustment mechanism (first twist amount adjustment mechanism)
17 Torsion adjustment mechanism (second torsion adjustment mechanism)

Claims (1)

A suspension device for a vehicle,
A pair of trailing arm members that support the wheels on both sides in the vehicle width direction of the vehicle;
A torsion beam member for connecting the pair of trailing arms;
A torsion bar member provided between the trailing arms and to which a torsional force generated between the wheels is input;
A twist amount control mechanism for controlling the twist amount of the torsion bar member ;
A stiffness variable device that has the torsion bar member and the torsion amount control mechanism, and sets the torsional stiffness of the entire suspension device;
With
The twist amount control mechanism is:
A first torsion amount adjusting mechanism in which a restraining force for restraining the torsion bar member is continuously variable according to a turning condition of the vehicle;
A second torsion amount adjusting mechanism that applies a load to the torsion bar member in a direction opposite to the torsion direction of the torsion bar member when there is additional steering during the steering of the vehicle;
Have
Suspension device comprising a call.

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