JPS5834692B2 - leaf spring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a leaf spring device, and more particularly to a leaf spring device in which the frictional force acting on a spring plate can be controlled depending on the state of a supported body.

For example, in a stacked plate spring device used in a vehicle suspension system, ride comfort and steering stability are affected by the spring constant and friction between the plates, and the extent of this is influenced by the vehicle's running speed and the condition of the road. In general, when driving on a good road, the lower the friction between the plates, the better the ride comfort, and the steering stability shows a tendency that is contrary to this.

On the other hand, in order to reduce the weight of vehicles and improve riding comfort, tapered spring plates, which have a tapered part that decreases in thickness toward the edge of the plate, have come to be used. The number of shock absorbers required is smaller than when one with a constant thickness is used, and the friction between the plates is small, so a large-capacity shock absorber is required to improve riding comfort when driving on rough roads.

However, a large-capacity shock absorber is not only expensive, but also provides a constant amount of damping even when damping is not necessary, which may impair riding comfort.

In addition, if a clamp mechanism is provided that tightens the leaf spring in the thickness direction to increase the friction between the plates, the friction between the plates is almost constant with the conventional bolt-tight clamp mechanism, so the ride comfort when driving on rough roads can be improved. If this is improved, the ride comfort when driving on good roads will deteriorate.

Furthermore, in a spring device used for vibration isolation of reciprocating machines, rotating machines, etc., it is desirable to increase the friction between the plates only when an impact or resonance occurs.

The present invention has been made under the above circumstances, and its object is to provide a leaf spring device capable of controlling the frictional force acting on a spring leaf depending on the state of a supported body such as a vehicle body or a mechanical device. Our goal is to provide the following.

Hereinafter, the present invention will be described with reference to an illustrated embodiment.

In FIG. 1, a main body 1 of a leaf spring device includes a plurality of (in the case of three spring plates in the figure) spring plates 2 which are overlapped in the thickness direction.

In the illustrated example, the metal parts of the spring plates 2... are tapered spring plates, but these metal parts or a part may not have a tapered part, and the lengths of the spring plates are different, and the steps It may be configured in a shape.

The spring plates 2 are configured such that their intermediate portions in the longitudinal direction are tightened in the thickness direction by appropriate means 3, as in the conventional device, and can be connected to, for example, the axle of a vehicle (as shown in the figure). There is.

Furthermore, eyeball portions 4.4 are formed at both ends of the first spring plate 2 and are connectable to the vehicle body (as shown) of the vehicle.

The main body 1 is provided with a clamp mechanism 5.5 located near the end of the plate for tightening the spring plates 2 in the thickness direction.

This clamp mechanism 5 includes a spring receiving member 6 disposed below the third spring plate, and a spring plate 2 and
The first spring has a pair of bolts 7.7 standing upright on both sides of the spring receiving member 6, and a through hole 8.8 into which these bolts 7.7 are loosely inserted. It includes a pressing member 9 disposed above the plate 2, and an insert 10 interposed between the pressing member 9 and the first spring plate 2.

Further, a fluid pressure cylinder device 11 is attached to the bolt 7.7.

That is, the cylinder device 11 includes a cylinder 14 having a flange portion 13 attached to a bolt 7゜7 by nuts 12, 12, and a piston 1 inserted into the cylinder 14.
5, a spring member 16 such as a disc spring installed inside the cylinder 14 so as to be able to bias the piston 15 in the direction toward the head;
A piston rod 17 is connected to a piston 15, and the tip of the piston rod 17, which loosely passes through the through hole 18 of the flange portion 13 and projects outward, faces the pressing member 9 so as to be able to press against it. .

The cylinder device 11 has a port 19 opened at the end of the cylinder 14 near the head, and the pressure fluid introduced from the port 19 tightens the spring plates 2 through the pressing member 9. It is configured as follows.

Further, the cylinder device 1111 is connected to a pressure fluid source 2 via piping 20 and a control valve 21 connected to each port 19, 19.
Connected to 2.

The control valve 21 is connected to a detection section 24 and an operation section 25 via a control section 23.

The control section 22 is configured to variably control the clamping force of the clamp mechanism 5 via the control valve 21 according to output signals from the detection section 24 and the operation section 25.

The detection unit 24 detects the vibration of the supported body, such as the acceleration (or speed or displacement amount) of the vertical vibration of the vehicle body, the operating angle of the steering wheel, the running speed, or the acceleration of vibration in mechanical equipment, etc. It is configured to be able to send out various desired signals related to the state.

The operation section 25 is configured to be able to send out desired manual operation signals.

When the device configured as described above is used in a vehicle suspension system, for example, if the operating section 25 is set appropriately to keep the output of the control section 23 constant, the cylinder device 11 is controlled via the control valve 21. Since the fluid pressure applied to the plate is maintained constant, the plate spring device operates as in the conventional one.

Furthermore, if the control valve 21 is set to increase the fluid pressure based on the output signal of the detection unit 24, for example, when the vibration amplitude of the vehicle body increases, the fluid pressure will be low when driving on a good road, so the dynamic spring constant will be small. Since the fluid pressure increases when driving on rough roads, the equivalent damping coefficient is set high and the damping performance becomes good.

Therefore, a good ride comfort can always be obtained regardless of the condition of the road.

Furthermore, when the vehicle turns, a control signal corresponding to the centripetal acceleration of the vehicle body is sent from the control unit 23 according to the operating angle of the steering wheel, the traveling speed, etc., and the fluid pressure is increased as the centripetal acceleration increases. By setting this, the dynamic spring constant is set high and tilting of the vehicle body due to centripetal acceleration is suppressed, thereby improving the steering stability of the vehicle when turning.

Further, when the device configured as described above is used as a vibration isolator for a rotating machine, for example, the vibration frequency N of the machine or the like is at the resonance point N, as illustrated in FIG.

If the detection unit 24 detects this when passing near the fluid, and controls the control valve 21 to increase the fluid pressure, the vibration transmissibility α can be improved as shown by the solid line in the figure. It is possible to obtain a vibration damping characteristic A.

In the figure, B shows the characteristics when the friction between the plates is maintained at a constant value of the conventional level, and C shows the characteristics when the stacked plate splash device and the shock absorber are combined.

Furthermore, according to the above structure, since the cylinder device 11 is provided in the clamp mechanism 5, the cylinder device 11 can be small, and a desired number of splash plates 2 can be installed at desired positions in the longitudinal direction. This does not have any effect on the original connection structure of the plate spring device, and it is also possible to attach it to the edge or center of the plate if necessary.

Note that the present invention is not limited to the above-mentioned embodiments, and can be applied to various objects other than vehicle suspension systems, vibration isolators, etc., for example.

In addition, the shape, number, etc. of the splash plates 2 constituting the main body 1 of the plate splash device can be set arbitrarily.

In short, the clamp mechanism 5 and the cylinder device 11 may be installed upside down on the splash plate 2, and an appropriate link mechanism or the like may be connected between the cylinder device 11 and the clamp mechanism 5. A means may be provided.

Further, as illustrated in FIG. 4, a cylinder device 30 that does not require the spring member 16 may be used, or the cylinder device and clamp mechanism may be provided only at one end of the main body 1, and if necessary, the cylinder device 30 may be used. A cylinder device and a spring bearing member 31 may be provided along the vehicle body 3, and a suppressing member 33 may be provided at the lower end of the piston rod 32.

In addition, various modifications and applications are possible within the scope of the gist of the present invention.

As described above, the present invention has a main body having a spring plate capable of elastically supporting a supported object, a ramp function that allows the spring plate to be tightened in the thickness direction, and a clamping mechanism for the spring plate. The present invention is characterized by comprising a control means capable of controlling the tightening force according to the state of the supported body.

Therefore, the frictional force acting on the spring plate can be variably set depending on the state of the supported object, so if the supported object is a car body, the dynamic spring constant can be adjusted depending on the running state and road condition. By controlling the equivalent damping coefficient and the like, ride comfort and handling stability can always be maintained in an optimal state.

Further, when the supported object is a mechanical device or the like, resonance, impact, etc. can be effectively suppressed.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing one embodiment of the present invention, and Fig. 2 is a system diagram showing an embodiment of the present invention.
FIG. 3 is a diagram for explaining the operation on the same side, and FIG. 4 is an explanatory diagram showing a modification of the main part. 1...Main body, 2...Spring plate, 5...
... Clamp mechanism, 6, 31 ... Spring receiving member, 9, 33 ... Pressing member, 11.30 ...
...Cylinder device, 15... Piston, 16.
... Spring member, 17, 32 ... Piston rod, 21 ... Control valve, 22 ... Pressure fluid source, 23 ... Control section , 24...
Detection unit, 25... Operation unit.

Claims (1)

[Claims] 1 A main body having a spring plate capable of elastically supporting a supported object, a ramp mechanism capable of tightening the spring plate in the thickness direction, and a clamp mechanism that applies the tightening force of a clamp mechanism to the spring plate to the spring plate. A leaf spring device characterized by comprising a control means that can be controlled according to the state of a support body.