JP2004106654A - Stabilizer device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stabilizer device excellent in travel stability, which continuously varies roll stiffness according to a load on an axle with a simple structure. <P>SOLUTION: The stabilizer device includes a stabilizer 3 having a torsion bar portion 1 and arm portions 2, 2 with a sectional shape different in flexural rigidity in arbitrary cross sectional directions, respectively, which connect an end of the torsion bar portion 1 to a chassis frame and extend in a longitudinal direction of a vehicle. This stabilizer device includes an arm portion revolving mechanism capable of revolving the arm portions 2, 2 around an axis of the longitudinal direction and an actuator 10 actuated to rotate the arm portions 2, 2 at an arbitrary rotating position according to loading weight of the vehicle. The actuator 10 is driven by air from an air spring 12, where pressure varies in proportion to the load on the axle 28, and rotates the arm portions 2, 2 at the arbitrary rotating position by using this air. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a stabilizer device that can increase or decrease the roll rigidity in accordance with a change in load weight, for example, when a load is loaded or when an empty vehicle is not loaded.
[0002]
[Prior art]
For example, a vehicle using an air suspension as a suspension device is generally set to have a lower spring constant than a vehicle using a metal spring (coil spring or leaf spring). For this reason, vehicles using an air suspension often use stabilizers because the roll stiffness is reduced only by the chassis spring and the steering stability of the vehicle is reduced.
[0003]
The stabilizer has left and right arms arranged in the longitudinal direction of the vehicle and a torsion bar arranged in the vehicle width direction and receiving a torsional reaction force are substantially U-shaped, and when the vehicle body is inclined with respect to the axle, the left and right arms are moved. The torsion bar portion at the center is twisted, and the torsional reaction force increases the roll rigidity of the vehicle body.
[0004]
The spring constant of the stabilizer is determined to a constant value by the torsional rigidity of the torsion bar part and the bending rigidity of the arm part, and the torsional rigidity of the torsion bar part and the arm part When the bending rigidity is increased, the roll inertia of the vehicle body becomes small when the vehicle is empty, so that the roll rigidity becomes too high, and the vibration of the vehicle body deteriorates. Conversely, if the torsional stiffness of the torsion bar and the bending stiffness of the arm are lowered to match the spring constant of the stabilizer with the load when the load is not loaded and the load is empty, the roll stiffness increases because the roll moment of inertia of the vehicle body increases during loading. It becomes too low, and steering stability during running decreases.
[0005]
Therefore, in order to solve these problems, a technique of changing the length of the left and right arms of the stabilizer to make the roll rigidity variable has been disclosed (for example, see Patent Document 1). Further, a technique is disclosed in which the roll rigidity is changed by changing the attachment span of the left and right arm portions of the stabilizer to the torsion bar portion (for example, see Patent Document 2). Furthermore, the torsion bar portion (lateral bar portion) and the left and right arm portions (lever portion) of the stabilizer are divided, and both ends of the torsion bar portion are supported by a movable support member, and the arm portion tilts following the wheel. (For example, refer to Patent Document 3).
[0006]
[Patent Document 1]
Japanese Utility Model Laid-Open No. 06-027222 (Page 6, FIGS. 1, 2 and 3)
[Patent Document 2]
Japanese Utility Model Publication No. 07-013513 (pages 11 and 12, FIGS. 4 and 5)
[Patent Document 3]
JP-A-09-267617 (pages 2 and 3; FIGS. 1 to 3)
[0007]
[Problems to be solved by the invention]
However, in the devices of Patent Literature 1 and Patent Literature 2, since the arm portion or the torsion bar portion of the stabilizer moves, it is necessary to secure a space for these movements. Further, Patent Document 2 requires a sensor for measuring a load applied to an axle and other vehicle conditions and a controller for controlling roll rigidity, so that the system is complicated. Further, in the device of Patent Document 3, a driving mechanism for moving the torsion bar portion up and down with respect to the vehicle body is complicated.
[0008]
The present invention has been made in order to solve the above-described problems, and without requiring extra space, the roll rigidity can be continuously varied according to the load applied to the axle with a simple mechanism, and the load It is an object of the present invention to provide a stabilizer device capable of suppressing vibration of a vehicle body when the vehicle is empty while suppressing excessive rolls during loading.
[0009]
[Means for Solving the Problems]
A stabilizer device according to the present invention includes a stabilizer having a torsion bar portion extending in a vehicle width direction of a vehicle, an arm portion connecting an end of the torsion bar portion and a chassis frame or an axle and extending in a vehicle front-rear direction, and an arm. An arm rotation mechanism is provided for rotatably rotating the arm in a direction around an axis about a longitudinal direction, and a rotation drive means for driving the arm so as to rotate the arm in accordance with the load weight of the vehicle. Further, in the present invention, the arm portion has a cross-sectional shape such that bending stiffness is different in an arbitrary cross-sectional direction. For example, an arm having a rectangular cross section is used.
[0010]
Then, in the stabilizer device of the present invention, as the loaded weight of the vehicle changes from a light state to a heavy state, the rotation driving means rotates the arm in a direction in which the bending rigidity in the vertical direction of the vehicle increases. For example, when loading a large amount of luggage, the arm is rotated so that the bending rigidity in the vertical direction of the vehicle is increased, and when the vehicle is empty, the arm is rotated so that the bending rigidity in the vertical direction of the vehicle is reduced.
[0011]
With this configuration, when the load weight is heavy, the rigidity of the stabilizer is increased, and the roll amount of the vehicle can be suppressed. When the load weight is light, the rigidity of the stabilizer is weakened, and the riding comfort of the vehicle is improved.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. This embodiment uses an air pressure in an air spring that changes substantially in proportion to a load applied to an axle to a vehicle (for example, a truck or a bus) using an air suspension as a suspension device, and uses a simple mechanism to provide an axle with a simple mechanism. The present invention is applied to a stabilizer device in which the roll stiffness can be continuously changed in accordance with the load applied to the roller.
[0013]
[Configuration of stabilizer device]
As shown in FIGS. 1 to 3, the stabilizer device according to the present embodiment includes a torsion bar 1 and a stabilizer 3 including left and right arms 2 and 2 provided at both ends of the torsion bar 1. An arm unit rotation mechanism for rotating the arm units 2 and 2 and a rotation drive unit for rotating the arm units 2 and 2 are provided.
[0014]
The stabilizer 3 includes a torsion bar 1 and arms 2, 2. The arms 2, 2 are arranged at both ends of the torsion bar 1 in the front-rear direction of the vehicle, and have a substantially U-shaped plane. As shown in FIG. 1, the torsion bar portion 1 is arranged on the axle 28 side so as to extend in the vehicle width direction (the direction of arrow Y in FIG. 1). Note that wheels 29, 29 are attached to both ends of the axle 28, respectively.
[0015]
When the vehicle body is tilted with respect to the axle 28, the torsion bar portion 1 generates a vertical displacement difference at the ends of the left and right arm portions 2 and 2 and is twisted under the influence of the displacement difference. The torsional reaction force increases the roll rigidity of the vehicle body. Works to enhance. The torsion bar portion 1 is formed, for example, as a round bar having a circular cross section, and is arranged with its longitudinal direction facing the vehicle width direction. Further, as shown in FIGS. 1 and 2, the torsion bar portion 1 has connecting portions 4 and 4 for connecting the arm portions 2 and 2 at both ends in the longitudinal direction. The connecting parts 4 and 4 are formed as short cylindrical bodies, and are integrated at both ends of the torsion bar part 1 with their axial direction substantially orthogonal to the longitudinal direction of the torsion bar part 1.
[0016]
As shown in FIGS. 1 and 2, the arms 2 and 2 are arranged so as to extend in the vehicle front-rear direction (the arrow X direction in FIG. 1). The arms 2 and 2 are formed as elongate flat plates having a substantially rectangular cross section, for example, and have different cross sectional shapes in the horizontal and vertical directions. As shown in FIGS. 1 to 4, these arms 2 and 2 have one end in the longitudinal direction attached to the torsion bar 1 and the other end attached to a stabilizer rod 6 fixed to the chassis frame 5. ing. Further, the arm units 2 and 2 are rotatable in a direction around an axis (the direction of the arrow Z in FIG. 2) around the longitudinal direction thereof by an arm unit rotating mechanism described later. In FIGS. 1 and 2, the arm portions 2 and 2 indicated by two-dot chain lines show a state in which the cross-sectional longitudinal direction is substantially horizontal.
[0017]
As shown in FIG. 5, the arm rotating mechanism includes rotating shafts 7 provided at both ends in the longitudinal direction of the arms 2 and 2, and a bearing 8 that rotatably supports the rotating shaft 7. FIG. 5 is an enlarged view of a main part showing a part of a connection portion between the arm parts 2 and 2 and the torsion bar part 1 partially broken away. The bearing 8 is made of, for example, a rubber bush, a sliding bearing, a rolling bearing, or the like, and is fitted into the holes 4a, 4a of the connecting portions 4, 4, respectively.
[0018]
The rotating shaft 7 is rotatable by being supported by the bearing 8. In the example of FIG. 5, a rubber bush with an inter ring is used as the bearing 8, and by inserting the rotary shaft 7 into the rubber bush, the arms 2, 2 are rotatable around the longitudinal direction. An example is shown below. The connecting portion 9 between the other ends of the arms 2 and 2 and the stabilizer rod 6 has the same configuration.
[0019]
As shown in FIG. 1, the rotation drive means includes an actuator 10 and an arm rotation lever 11 for rotating the arms 2 and 2 by the operation force of the actuator 10. As shown in FIG. 3, the actuator 10 is interposed between the chassis frame 5 and the axle 28 and is connected via a pipe 13 to an air spring 12 that suspends the axle 28 on the chassis frame 5. . The actuator 10 is fixed on an air spring support beam 14 that supports the air spring 12.
[0020]
Since it is not desirable that the roll stiffness changes due to a change in the dynamic load due to unevenness of the road surface or the like, an orifice is inserted into the pipe 13 connecting the air spring 12 and the actuator 10 so that the actuator 10 can be driven only by a static load. It is desirable to be able to operate.
[0021]
The actuator 10 includes an air chamber 15, a piston 16 slidable in the air chamber 15, and a rod 18 having one end connected to the piston 16 and the other end connected to the arm rotation lever 11 by a pin 17. And a spring 19 that constantly urges the piston 16 toward the air chamber 15 and is driven by air pressure fed from the air spring 12, and the amount of operation is continuously changed by a change in the air pressure. ing.
[0022]
In the case of an air suspension, the pressure in the air spring 12 changes substantially in proportion to the load applied to the axle 28 when the vehicle is stationary. That is, when the load is large and the load applied to the axle 28 is large, the pressure in the air spring 12 increases in proportion to the load. When the load is small and the load applied to the axle 28 is small, the pressure in the air spring 12 is the load. It becomes low according to. Therefore, the pressure in the air chamber 15 of the actuator 10 connected to the air spring 12 via the pipe 13 similarly changes, and the operation amount of the actuator 10 continuously changes according to the loading condition on the vehicle. Become.
[0023]
As shown in FIG. 5, the arm rotation lever 11 is fixed to the distal end side of the rotation shaft 7 that protrudes out of the coupling parts 4 and 4. The arm rotating lever 11 is fitted with a key (not shown) in a key groove 20 formed in the rotating shaft 7 so as to rotate integrally with the arm 2, 2. It is fixed at 2. The arm portion rotation lever 11 is securely fixed to the rotation shaft 7 by tightening a nut 22 on a screw portion 21 formed on the tip side of the rotation shaft 7.
[0024]
In the stabilizer 3 configured as described above, the bending stiffness of the left and right arms 2 and 2 and the torsional stiffness of the torsion bar 1 are combined as a series spring. For this reason, as shown in FIG. 3, when the bending rigidity of the arms 2 and 2 is high in the vertical direction of the vehicle body (for example, in the case of a rectangular cross section, in the case where the longitudinal direction of the cross section is vertical), the entire stabilizer 3 As shown in FIG. 4, when the spring constant is high and the bending rigidity of the arms 2 and 2 is low in the vertical direction of the vehicle body (for example, in the case of a rectangular cross section, or when the longitudinal direction of the cross section is horizontal), the entire stabilizer 3 is used. The spring constant is lower.
[0025]
Therefore, when an empty vehicle is not loaded with a load, the spring constant of the entire stabilizer 3 is low (in the case of a rectangular cross section, the arms 2 and 2 are arranged so that the longitudinal direction of the cross section is substantially horizontal). The actuator 10 is driven so that the spring rate of the entire stabilizer 3 is increased (in the case of a rectangular cross section, the arms 2 and 2 are arranged so that the longitudinal direction of the cross section is substantially vertical). To rotate.
[0026]
[Description of operation]
Next, the operation of the stabilizer device according to the present embodiment will be described. First, as described above, the arms 2 and 2 are arranged so that the longitudinal direction of the cross section becomes substantially horizontal when the vehicle is empty, and the arms 2 and 2 are arranged such that the longitudinal direction of the cross section becomes substantially vertical when the vehicle is loaded. Is set to be placed.
[0027]
For example, when a load is loaded on a vehicle, the load applied to the axle 28 increases, and accordingly, the pressure in the air spring 12 increases substantially in proportion to the load applied to the axle 28. Then, air is introduced from the air spring 12 to the air chamber 15 of the actuator 10 via the pipe 13, and the introduced air causes the piston 16 to advance in a direction to expand the air chamber 15. When the piston 16 advances, the rod 18 connected to the piston 16 rotates the arm rotation lever 11, and as shown in FIG. 3, the arms 2, 2, so that the longitudinal direction of the cross section becomes substantially vertical. To rotate.
[0028]
When the arms 2, 2 rotate so that the longitudinal direction of the cross section becomes substantially vertical, the bending rigidity of the arms 2, 2 increases, and the spring constant of the entire stabilizer 3 increases. Therefore, an excessive roll at the time of loading can be suppressed, and the running stability of the vehicle can be improved.
[0029]
On the other hand, when the luggage is unloaded from the vehicle and becomes empty, the load applied to the axle 28 decreases, and accordingly, the pressure in the air spring 12 decreases substantially in proportion to the load applied to the axle 28. Then, the air in the air chamber 15 moves to the air spring 12 via the pipe 13, and accordingly, the piston 16 retreats in a direction to narrow the air chamber 15. When the piston 16 retreats, the rod 18 connected to the piston 16 rotates the arm rotation lever 11 in a direction opposite to the previous direction, and as shown in FIG. The arm parts 2 and 2 are rotated so as to be as shown in FIG.
[0030]
When the arms 2, 2 rotate so that the longitudinal direction of the cross section is substantially horizontal, the bending stiffness of the arms 2, 2 decreases, and the spring constant of the entire stabilizer 3 decreases. Therefore, vibration of the vehicle body when the vehicle is empty can be suppressed.
[0031]
FIG. 3 shows a state in which the arms 2 and 2 are arranged in a direction in which the spring constant of the stabilizer 3 is maximized, and FIG. 4 shows a state in which the arms 2 and 2 are rotated in a direction in which the spring constant of the stabilizer 3 is minimized. In the stabilizer device according to the present embodiment, the arms 2 and 2 rotate continuously in accordance with the load weight. For example, when the load is gradually lowered from the state where the load is loaded on the truck, the load applied to the axle 28 also decreases accordingly, and the arm portions 2 and 2 are continuously bent in conjunction with the decrease in the load. Rotate in a direction to decrease rigidity.
[0032]
As described above, the roll rigidity can be continuously varied according to the change in the load applied to the axle 28, and the vibration of the vehicle body when the vehicle is empty can be suppressed while suppressing excessive rolls during loading. Further, since the arm portions 2 and 2 rotate about their longitudinal direction as an axis, no extra space is required as compared with a stabilizer device which increases the roll rigidity by freely moving the arm portions 2 and 2 in the vehicle longitudinal direction. Further, since the actuator 10 is driven by the air pressure of the air spring 12 in which the internal pressure changes in proportion to the load applied to the axle 28, there is no need to provide a sensor or the like for measuring the load weight, which is simple. With such a configuration, the spring constant of the stabilizer 3 can be arbitrarily changed.
[0033]
[Other embodiments]
As described above, the specific embodiments to which the present invention is applied have been described. However, the present invention is not limited to the above-described embodiments, and can be variously modified.
[0034]
For example, in the above-described embodiment, the actuator 10 is driven by the air pressure of the air spring 12 in which the internal pressure changes in proportion to the change in the load applied to the axle 28, but a sensor for measuring the load weight is separately provided. The actuator 10 may be driven according to the output value from the sensor.
[0035]
In the above-described embodiment, the independent actuators 10 are used to rotate the left and right arms 2 and 2, respectively. However, the left and right arm rotation levers 11 that rotate the arms 2 and 2 are connected by a link. Thus, the actuator 10 can be reduced to one.
[0036]
Further, in the above-described embodiment, the left and right arms 2, 2 are respectively rotated. However, only one of the left and right arms 2, 2 may be rotated.
[0037]
Further, in the above-described embodiment, the torsion bar portion 1 is arranged on the axle 28 side, but the same effect can be obtained by disposing it on the frame side (for example, between the right ends of the arm portions 2 and 2).
[0038]
Further, in the above-described embodiment, a key is inserted into a key groove formed in the rotating shaft 7 to fix the rotating shaft 7 and the arm rotating lever 11. 11 may be fixed using a pin or the like.
[0039]
In the above-described embodiment, the other ends of the arms 2 and 2 are connected to the chassis frame 5 via the stabilizer rod 6, but the other ends of the arms 2 and 2 are connected to the axle 28 described above. You may make it connect.
[0040]
Further, in the above-described embodiment, the arm portions 2 and 2 are formed as long flat plates having a substantially rectangular cross section, but the arm portions 2 and 2 are not limited to the above-described shapes. .
[0041]
For example, FIG. 6 (a) shows the arm portion 23 having an elliptical shape, FIG. 6 (b) shows the arm portion 24 having a diamond shape, and FIG. 6 (c) shows that the arm portion 25 has an I-shape. It was done. Further, the arm portions 23, 24, and 25 in FIGS. 6A to 6C may have a hollow cross-sectional shape. FIG. 6 (d) shows a hollow arm portion 26 having a rectangular cross section, and FIG. 6 (e) shows a hollow arm portion 27 having an elliptical cross section.
[0042]
Of course, the arm portion is not limited to the simple cross-sectional shape as shown in FIG. 6, and may have a more complicated shape as long as the cross-sectional shape has a different bending rigidity in an arbitrary cross-sectional direction.
[0043]
【The invention's effect】
The present invention is implemented in the form described above, and has the following effects.
[0044]
According to the present invention, the spring constant of the stabilizer is made variable by rotating an arm having a cross-sectional shape having a different bending rigidity in an arbitrary cross-sectional direction in accordance with the load applied to the axle, so that the roll rigidity can be continuously increased. It can be varied, and while suppressing excessive rolls during loading, vibration of the vehicle body when the vehicle is empty can be suppressed, and a stable running state can be ensured.
[0045]
Further, according to the present invention, since the arm portion is configured to rotate around the axis about the longitudinal direction thereof, unlike the stabilizer device for moving the arm portion in the vehicle front-rear direction, no extra space is required.
[Brief description of the drawings]
FIG. 1 is a plan view of a stabilizer device according to the present embodiment.
FIG. 2 is a side view of the stabilizer device of the present embodiment.
FIG. 3 is a perspective view of the stabilizer device showing a state in which an arm portion is rotated so that a longitudinal direction of a cross section is vertical to increase bending rigidity.
FIG. 4 is a perspective view of the stabilizer device showing a state in which the bending rigidity is reduced by rotating the arm so that the longitudinal direction of the cross section is horizontal.
FIG. 5 is an enlarged view of a main part showing a connection part between an arm part and a torsion bar part, partially cut away;
FIG. 6 is a sectional view showing another shape of the arm portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Torsion bar part 2 Arm part 3 Stabilizer 8 Bearing 10 Actuator 11 Arm part rotating lever 12 Air spring 15 Air chamber 16 Piston 18 Rod 28 Axle 29 Wheel

Claims (3)

A torsion bar portion extending in a vehicle width direction of the vehicle, and an arm extending in the vehicle front-rear direction by connecting an end of the torsion bar portion to a chassis frame or an axle and having a cross-sectional shape having different bending rigidities in any cross-sectional direction. A stabilizer having a section and
An arm rotating mechanism that allows the arm to be rotatable around a longitudinal axis thereof;
A stabilizer for rotating the arm according to the load weight of the vehicle. The stabilizer device according to claim 1, wherein
An air spring interposed between the chassis frame and the axle, suspending the axle on the chassis frame,
The rotation driving means drives in accordance with the air pressure of the air spring. The stabilizer device according to claim 1 or 2, wherein:
The stabilizer device according to claim 1, wherein the rotation driving unit rotates the arm in a direction in which the bending rigidity of the arm in the vertical direction of the vehicle increases as the loaded weight of the vehicle changes from a light state to a heavy state. .

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