JPS5830542A - Variable shock absorber - Google Patents

Abstract

PURPOSE:To obtain good running condition by a method wherein the height condition of a vehicle upon excessive loading or the like is detected by the height value signal of the vehicle to increase the damping force of a shock absorber. CONSTITUTION:When an exciting current is supplied to a coil 50 and a plunger 52 is attracted and moved to the left against a spring 54, a variable orifice 40 is closed by a valve 52a and, under this condition, the communicating sectional area of a shock absorber becomes a small area determined by orifices 30, 32 or the same 33, 34, thereby enabling to vary and adjust the damping force temporarily. Accordingly, feeling upon riding on a vehicle and the steering stability of the vehicle may be improved by a method wherein the exciting current is supplied to the solenoid coil 50 by the height value signal of the vehicle when a predetermined height condition of the vehicle or the height of the vehicle is reduced to a value less than a predetermined value.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable shock absorber device, and more particularly to a modified variable shock absorber device that can obtain a damping force suitable for the driving conditions of a vehicle.

As is well known, there is a mechanism that uses a hydraulic shock absorber A for vehicles, etc., and by using this alone or in combination with other springs, etc., it is possible to improve ride comfort and maneuverability for vehicles. It will be possible to obtain an eggplant pension.

A typical hydraulic shock absorber includes a hydraulic piston interposed between the vehicle body side and the wheel side, and its damping force is always kept constant under certain conditions. In other words, the damping force is normally determined by the cross-sectional area of an orifice that flows through two hydraulic chambers separated by a piston, and in conventional devices, the damping force is constant because the flow cross-sectional area of the orifice is constant. The damping force under these conditions was always kept constant.

However, with such a constant damping force, it is not necessarily possible to perform the optimal shock absorption effect when the vehicle is actually running, and according to the results of recent vehicle running experiments, It has been concluded that it is preferable to change the damping force of the shock absorber A accordingly.

In particular, the constant damping force of the shock absorber mechanism mentioned above is normally set to suit when driving at a constant speed. This has the disadvantage that it does not fit with the vehicle body, resulting in reduced ride comfort or handling stability.

For example, the driving conditions caused by the increase in vehicle height are as follows:
An example of this is when the loaded weight of the vehicle, that is, the number of passengers or cargo, increases.In normal cases, the vehicle body sinks as the loaded weight increases, and at this time, the balance between the normal lower load and the ∆ upper load of the suspension mechanism is disrupted. A problem has arisen in that ride comfort and handling stability are reduced.

Further, when the vehicle is traveling on a rough road, the height of the vehicle changes greatly irregularly, and in such a case, there is a problem in that the ride comfort or steering stability of the vehicle decreases.

When the loaded weight increases or when driving on a rough road, it is preferable to increase the damping force of the suspension mechanism, that is, the shock absorber A device, thereby improving ride comfort and steering stability. is recognized. However, as described above, the conventional shock absorber 2 mechanism has the disadvantage that the damping force is kept at a constant value, and therefore the optimum running condition cannot be obtained.

The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to provide an improved vehicle that can increase the damping force of shock absorbers under predetermined vehicle height conditions to obtain good driving conditions. K provides a variable shock absorber A device.

In order to achieve the above object, the present invention provides a variable orifice which is incorporated in a hydraulic shock absorber and whose flow cross-sectional area can be adjusted in order to change the damping force of the shock absorber A; A solenoid built into the cVs Tsuku Absorber (to change the flow cross-sectional area of the orifice), a vehicle height sensor that electrically detects the vehicle height value,
a control circuit that reduces the flow cross-sectional area of the variable orifice by supplying an excitation current to the solenoid P based on the detection signal of the vehicle height sensor, and damps the shock absorber/sensor under predetermined vehicle height conditions. Characterized by increasing power.

Preferred embodiments of the present invention will be described below based on the drawings.

1 shows a preferred embodiment of a hydraulic shock absorber 2 mechanism of a variable shock absorber system suitable for the present invention.

Shock absorber cylinder/10 is inner @12 and outer cylinder 1
4, and between both cylinders 12 and 140 there is a hydraulic reservoir A chamber 1.
00 is formed. A bottom plate 16 is hermetically fixed to the lower end of the outer cylinder 14, and a baffle plate 18 is similarly hermetically fixed to the upper end. Moshi [.

The inner cylinder 12 is housed and held within the outer cylinder 14 by a bottom holder/20 fixed to its lower end and a top holder/22 fixed to its upper end.

A gas cylinder 24 is provided in the cylinder 10 so as to be slidable in the axial direction thereof, and the inside of the inner cylinder 12 is connected to the first hydraulic chamber 102 and the second hydraulic chamber 104 by the two stores 24. Isolated. The piston 24 is fixed to one end of the male piston rod P26.
The other end protrudes outward from the upper end of the cylinder/10. An oil seal 28 is provided between the piston rod P26, the top of the outer cylinder 14, and the plate 18.
o< When the four pistons r26 slide in the axial direction,
This prevents the pressure oil filled in the hydraulic reservoir/room ioo, the first hydraulic chamber 102, and the second hydraulic chamber 104 from leaking.

The piston 24 is provided with a fixed orifice 3° on the extension side and a variable orifice 32 on the extension side, and a contraction check knob 31 is engaged with both orifices 30, 32 to determine the direction of flow. Similarly, bottom holder 2o
is provided with a fixed orifice 33 on the contraction side, a variable orifice 34 on the contraction side, and an extension check Δ-lube 35.

Therefore, when the piston 24 extends upward with respect to the cylinder/10, the oil in the first hydraulic chamber 102 passes through the fixed orifice 3o on the extension side and the variable orifice 32 on the extension side.
It moves to the hydraulic chamber 104, and the damping force at this time is determined by the flow cross-sectional area of the extension side identification orifice 3o in the low speed range, and determined by the flow cross-sectional area of the extension side variable orifice 320 in the middle and high speed ranges. Similarly, when the piston 24 contracts downward relative to cylinder/1 (l), conversely, the second hydraulic chamber 1
04 oil flows through the compression side fixed orifice 33 and the compression side variable orifice 34 to the first hydraulic chamber 102, and the damping force at this time is as follows: This will be determined by the flow cross-sectional area of the variable office V-ice 34 on the contraction side.

When the piston 24 expands and contracts, both hydraulic chambers 102°10
Oil from the hydraulic reservoir 231100 can also flow to the inner cylinder 12, and for this purpose, the bottom holder/20 and the top holder 22 provided at the lower end of the inner cylinder 12 are provided with predetermined communication holes. There is.

The structure of the basic hydraulic shock absorber mechanism explained above is the same as the conventional one, but in the present invention, a variable orifice and a solenoid P for operating this variable orifice are incorporated in the shock absorber. Features.

A 14m open tube is formed in the garden, and this 14m open tube
A plug 38 is hermetically fixed to.

A variable orifice 40 is provided in the plug 38 in parallel to the axial direction of the cylinder 10. There are hydraulic pressure points between one end of the variable orifice 40 and the top hole/22!
A conduit 42 passing through 100 is connected and fixed, and the conduit 42
An end of the top holder/22 is connected to the first hydraulic chamber 102 via a communication port 22m formed in the top holder 22. Further, the other end of the variable orifice 40 is connected to a hydraulic lisano 10.
0 to the second hydraulic chamber 104.

The plugs 3 and 8 are formed with a slot 38 that crosses the variable orifice 40 in a direction perpendicular to the variable orifice 40, and by changing the amount of blockage of the slot 38, the flow cross-sectional area of the variable orifice 400 can be adjusted. It becomes possible to make adjustments.

In order to change the amount of blockage of the slot 38m, in the present invention, a solenoid I'44 is incorporated and fixed in the pump azo saw A. That is, a case 46 of the solenoid P44 is fixed to the plug 38, a core 48 is fixed to the case 46, and around the core 48;
The winding is fixed. A plunger 52 is slidably housed in the core 48 and the plug 38 along the axis of the solenoid P44, and a valve portion 52m provided at the tip of the plunger 52 is inserted into the slot 381 of the plug 38. The flow cross-sectional area of the variable orifice 40 is adjusted by the sliding position of the valve portion 521.

In this embodiment, a 1 mK open groove 53 is provided in the valve part 52a of the syringe 52 on its side, and when the coil 50 is in a non-energized state, the open groove 53 is connected to the variable orifice 40 as shown in FIG. The shock absorber is opposed to the orifice 30 provided in the piston 24.
．． 32 or 33, 34 and the variable orifice 40, the damping force is determined to be a constant value.

Then, the field 50 is connected to an excitation circuit, which will be described later.
6, the plunger 52 is supplied with an excitation current through the first
When suction is moved to the left in the figure against the spring 54, 1
, the variable orifice 4o is closed by the valve part 52akJ: in this state, the flow cross-sectional area of the shaft A has a small page area determined by the orifices 30, 32 or 33, 34, and the damping force is temporarily reduced. It is possible to make large changes and adjustments.

FIG. 2 shows a car 7II4-kyos 60 and its control movement 4 for controlling the excitation of the lunoid coil 5o. The vehicle height sensor 6o consists of an I-ten V meter installed on the rear side of the vehicle, and an electrical vehicle height detection signal is supplied from the slider 64 to the control circuit 62, and the vehicle's running condition 1 [K
Accordingly, a vehicle height detection signal indicated by Vt ec in FIG. 3 is obtained.

The vehicle height detection signal v1 is converted into an average vehicle height signal V after vibration components with relatively short periods are removed by a filter circuit 66. This average vehicle height signal V, is supplied to one input of a comparator 68 consisting of an operational amplifier, and is compared with the vehicle height reference value V, supplied to the other input of the comparator 68. The amount is a constant value, that is, the vehicle height reference value v6
A sinking signal V is output when the temperature drops below V. This sinking signal V.

is supplied to the solenoid drive circuit 72 via the OR gate 70, and an excitation current is supplied to the solenoid P coil 50 when a predetermined vehicle height condition is met, that is, when the vehicle height drops below a certain value. The solenoid drive circuit 72 includes a transistor, a resistor, and a diode, and the output V of the OR gate 70
, is rHJ, the transistor is turned on and a desired excitation current is supplied to the solenoid P coil 50.

The vehicle height detection signal V is further supplied to one input of a comparator 74 consisting of an operational amplifier, a resistor, and a diode,
The other input of this comparator 74 is the average vehicle height signal V,
is supplied, the comparator 74 outputs a signal corresponding to the amount of vibration of the vehicle height with respect to the average vehicle height, and this signal is further integrated by the integrator 76 and output from the operational amplifier as the vehicle vibration signal V. is supplied to one input of a comparator 78 consisting of:

The other input of the comparator 78 receives the rHJ rail rough road detection signal V when the supply exceeds the runout reference value v4.
is output to the above-mentioned or game) 7G.

Therefore, as is clear from Fig. 3, in the case of an increase in the number of passengers or an overloaded cape, the vehicle height decreases below the reference value, and when the average vehicle height signal V, falls below the vehicle height reference value V, the comparison Seven sinking signals are output from the device 68, and as a result, the rHJ failure signal V is supplied from the OR gate 70 to the solenoid drive circuit γ2.Similarly, when the vehicle is traveling on rough roads, the vertical vibration of the vehicle body increases , when the vibration from the average vehicle height exceeds a certain value, that is, when the vehicle vibration signal V exceeds the vibration reference value V, a rough road detection signal V is output,
As a result, the OR gate 70 outputs the rHJ level signal V.
, is output.

Therefore, under each of the above vehicle height conditions, the desired excitation current is supplied from the solenoid drive circuit 72 to the solenoid P coil 50, and as a result, as described above, the sylanger 52 of the shock absorber 2 mechanism is By moving to the left, the flow cross-sectional area of the variable orifice 40 is reduced, and in the embodiment, it is closed, so that the damping force of the shock absorber A can be temporarily controlled significantly.

In the embodiment, the damping force of the shock absorber is controlled in two types, but it is also possible to change the damping force continuously by using, for example, a linear solenoid.

Therefore, under certain vehicle height conditions, such as when overloaded or when driving on a rough road, the braking force of the shock absorber increases.
It can absorb vibrations from the vehicle body and significantly improve ride comfort and handling stability.

As explained above, according to the present invention, the damping force of the B Tsuku absorber A can be increased under a certain vehicle height condition, and the vehicle height condition in the present invention is the above-mentioned sinking or rough road driving. In addition, in the present invention, the shock absorber A mechanism for controlling the damping force may be provided on the four-wheel metal part (and for excessive loading conditions, etc., it may be provided later). It is also possible to provide only the rings, and it is preferable to install an arbitrary number of control circuits in parallel depending on the number of these installed.

[Brief explanation of the drawing]

FIG. 1 is an outline diagram showing an embodiment of a shock absorber mechanism suitable for the variable shock azoso A device according to the present invention, and FIG. 2 is a circuit diagram showing a vehicle height sensor and control circuit suitable for the present invention. Figure 3 is a time chart diagram of Figure 2. 10...Cylinder, 12--Inner cylinder, 14--Outer cylinder, 24--Piston 1. 40.-Variable orifice, 44.-Solenoid, 50.-Coil, 52.-Plunger, 60.-Vehicle height sensor, 62.. Control circuit.

Claims (1)

[Claims] (1) A variable orifice that is incorporated in the hydraulic pressure absorber A and whose flow cross-sectional area can be adjusted to change the damping force of the shock absorber A, and a shock absorber that can adjust the flow cross-sectional area of the variable orifice. Abso AVC
Based on the built-in solenoid, a vehicle height sensor that electrically detects the vehicle height value, and a detection signal from the vehicle height sensor, an excitation current is supplied to the Nlenoid P to reduce the cross-sectional area of the variable orifice. A variable shock absorber device comprising a control inner path and increasing the damping force of the shock absorber A under a predetermined vehicle height condition.