JPS604803A - Regulator for stroke of piston - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a vibration damper, a gas spring and a hydraulic pneumatic cylinder, the piston of which is filled with at least one damping medium via a piston rod and which is disposed axially movably in a cylinder. The present invention relates to a piston stroke adjusting device consisting of a hydraulic, pneumatic or hydropneumatic assembly such as a spring.

For example, the spring device is
It is known from No. 2.433, in which each spring device unit of a vehicle for adjusting its platform height has a sensor component which generates a magnitude of an output that is progressively changed by the platform. There is. In this regard, one platform height sensor is provided for each valley spring device unit for adjusting the distance of the platform, i.e. between sprung and unsprung vehicle parts. There are drawbacks. Such a device is particularly complex, since corresponding measured values must be detected between the vehicle suspension and the specific spring arrangement. This measurement value detection is expensive, since corresponding measurement receivers must be provided for different vehicle parts.

It is therefore an object of the present invention to provide a method for measuring the piston stroke which operates contact-free and reliably, so that integration in the spring system of a vehicle can occur in small dimensions. There is a particular thing.

To solve this problem, according to the present invention, a first electrode movable in the axial direction is formed directly or indirectly by the piston and/or the piston rod and is arranged insulated in the internal space of the cylinder. It is proposed that the capacitor is formed such that the second electrode, which is attached to the capacitor, is fixedly held within the cylinder, and that the first and second' electrodes are separated from each other by a dielectric.

In this case, the physical measuring method, which operates without contact, allows for a compact measuring device construction, so that the measuring device can be installed without major changes, for example in vibration dampers, gas springs or hydropneumatic springs. It has the advantage of being able to be integrated.

Furthermore, it would be advantageous to have a cost-effective spring system for the vehicle, which can be provided as a closed unit together with the stroke adjustment device.

According to other main characteristics, the first? The piston rond is formed hollow as the il pole, the hollow space of the piston rond being provided with spaced apart tubes fixed in the cylinder bottom and disposed insulated as the second electrode. , and it is proposed that the first electrode may be telescopically movable in relation to the second electrode.

In particular, the structure of the hydropneumatic vibration damper is such that, with slight modifications, an additional hollow cylinder can be arranged, which is accommodated in the insulation at the bottom of the cylinder by means of an oil-filled cylinder and a hollow piston rod. It turns out to be convenient. The variable surface variation creates a cylindrical capacitor that generates a capacitance variation, so that the measured value is maintained in the form of a varying physical magnitude.

Capacitive piston stroke measurement is produced by a cylinder capacitor of the form:

1 here, EO=B electric rate E, = relative dielectric constant Lη = piston stroke length r2 = radius of piston rond hole r□=radius of hollow cylinder attached to cylinder π = 3.14159 shows.

Actuation is produced by the movable piston stroke being moved through a hollow cylinder which is insulated and fixed to the bottom of the cylinder. This results in changes in the cylinder surface and, therefore, in the volume depending on the piston stroke. A hollow piston rod on the one hand and a tube fixed to the cylinder bottom on the other hand are formed as electrodes.

According to a further embodiment, it is proposed that the second electrode is arranged in the cylinder and the side of the piston facing the cylinder bottom is formed as the first electrode.

Also in this embodiment, the capacitor is formed by the component itself of the assembly provided in the splash device. Thereby, a capacitance change is generated by the variable distance between the two electrodes and strictly based on the following calculation formula.

here, Eo = electric field constant E = relative dielectric constant of oil A = surface C=capacitance L = length shows.

This calculation shows that the length, ie the distance between the piston and the piston bottom, causes a capacitive change by which the corresponding measured value is maintained.

According to another embodiment, the electrodes of the capacitor are connected to a capacitive measuring bridge and connected via an amplifier to generate a corresponding electrical measured value, which can be used, for example, for controlling the horizontal height of the vehicle. It is proposed to generate a corresponding electrical magnitude with 0. Another object is to configure such a device in such a way that it simultaneously allows pressure and temperature compensation in addition to the evaluation of variable capacitances.

To solve this problem, the cylindrical space of the tube fixed to the bottom of the cylinder is further provided with another fixedly arranged tube at a distance, the other tube fixed as an additional electrode of said tube. It is proposed to form a capacitor with a capacitance.

In this configuration, it is advantageous for the insulating structure of the additional metal cylinder to create a capacitor with a fixed capacitance in the electrode already present at the bottom of the cylinder as an additional electrode. Thereby retaining the advantages of a capacitive abscission consisting of a variable capacitance, a drawer (by movement of the piston stroke) and a capacitance fixed in a fixed cylinder bottom.

In addition to a good evaluation of the variable capacitance, this arrangement allows simultaneous pressure and temperature compensation, since the relationship between both capacitances is taken into account by appropriate electronics.

In the embodiment of the invention, it is proposed that the tube and further tubes are arranged insulated from each other, in which case the other tubes can likewise be fastened to the cylinder bottom.

Alternatively, in order to solve the set task, it is proposed according to the invention that the outer sleeve surface of the cylinder has at least one winding that generates a magnetic field over the range of the piston stroke.

Advantageously, an induced magnetic field is generated in this case.

A piston inserted into this magnetic field of the vibration damper thereby generates an increased inductance, so that after measurement and conversion of the inductance in electrical magnitude, an adjustment of the piston stroke can likewise be carried out. The method is also useful, for example, if the magnitude of the power is used as a basis for leveling the vehicle.

Another embodiment of the invention proposes that two windings are provided which are separated perpendicularly to the axis of rotation of the cylinder, each winding covering half of the piston stroke. In this embodiment, it is advantageous that the piston rod can be made rigid and hollow without being forced.

Such a winding configuration creates two inductances that can be made direct components of an inductive measuring bridge.

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

The vibration damper shown in FIG. 1 essentially consists of a cylinder 1, a piston 2 and a piston rod 3.

In the hollow space 4 of the cylinder 1 there is a damping medium used for vibration damping. Fixing devices 5 and 6 are provided for fixing the vibration damper to the vehicle. The piston rod 3 formed in the hollow is moved telescopically over the tube 7. As a result, the tube 7 is fixed in the cylinder to an insulating material 8 and is insulated from the rest of the components of the pickup damper. The hollow piston rod 6 and the tube 7 form a cylinder capacitor, so that the damping medium present in the hollow cavity 4 acts as a dielectric for the capacitor. The hollow piston rod 3 forms a first electrode and is connected via a lead 10 to a corresponding measurement value receiver.

The slope of the capacitance change depends on the distance between the outer surface of the tube 7 and the inner surface of the hollow piston rod 5 and on the medium present between the ribs. The hollow piston rod has the same spacing as 141 with respect to the tube 7.
A space formed on both sides and arranged in a positive direction accommodates a dielectric material.

FIG. 2 schematically shows a cylinder capacitor, with the first pole representing the inner wall piston rod 3 and the second electrode representing the tube 7. The figure shows the distance #, where 11 is the minimum shape of both surfaces and the distance 12 is the maximum shape of both surfaces, correspondingly correspondingly converted to the current piston stroke, i.e. the piston in the cylinder. The leads 9 and 10 are used for connection to a capacitive bridge, for example.

FIG. 6 is a diagram showing the dependence of the capacitance for such a cylinder capacitor on the piston stroke. The capacitance change then occurs in proportion to the piston stroke, and the slope of the measurement curve depends on the inner radius of the piston rod bore, the outer radius of the insertion tube 7 and the lW, l ratio of the dielectric constant ER.

The dielectric constant ER is provided by a corresponding damping medium.

FIG. 4 also schematically shows a photographic damper comprising a cylinder 1, a piston 2 and a piston rod 3. The piston 2 and the cylinder bottom 13 are formed as first and second "g poles. 1, so that the desired volume change can be adjusted according to the variable distance of the piston 2 relative to the cylinder bottom 16. In this construction, the position of the piston can also be adjusted by a corresponding transformation of the measured values. Can be verified.

FIG. 5 shows a vibration damper (in cross-section) as an alternative embodiment, in which again the cylinder 1, the piston 2 and the piston rod 6 form the main components of the vibration damper. The sleeve surface 14 is provided with a winding 15 so that a first coil 16 and a second coil 17 are formed for the generation of the magnetic field. The transverse force is subjected to a pressure measurement, so that an appropriate size exists corresponding to the piston stroke.

FIG. 6 shows yet another embodiment. The main components of the oscillating device are once again the cylinder 1, the piston 2 and the piston rod 6, which must not be designed hollow in the structure with inductance. . A winding is mounted on the outer sleeve surface of the cylinder 1 over the entire stroke of the piston. Upon insertion of the piston into this region, a change in the inductance occurs which can be evaluated accordingly.

The vibration damper shown in FIG. 71 essentially consists of a cylinder 1, a piston 2 and a piston rod 3. In the hollow space of the cylinder 1 there is a damping medium used for vibration damping. Fixing devices 5 and 6 are provided for fixing the vibration damper to the vehicle. Piston rod 6 formed hollow
is telescopically moved over the straddle 7, the tube 7 in the cylinder being fixed to an insulating material 8 and insulated from the remaining components of the vibration damper. The hollow piston rod 6 and the tube 7 together form a cylindrical capacitor, the damping medium in the hollow space 4 being formed as a dielectric for the capacitor. The hollow piston 6 forms the 114th pole and the tube 7 forms the second stationary voltage gate and is connected via a lead 10 to a corresponding measured value receiver.

The slope of the capacitance change depends on the distance between the outer surface of the tube 7 and the inner surface of the hollow piston rod 3 and the medium between them. The hollow piston rod is arranged coaxially at a distance from the tube 7 and the space formed on both sides accommodates the dielectric.

In that case, the distance 11 is the minimum shape of both surfaces, and the distance 12
indicates the maximum overlap of both surfaces and produces a correspondingly variable current piston stroke, ie a minimum or maximum displacement indicating the position of the piston in the cylinder.

A further tube 18 is fixed in the cylindrical interior space 19 of the tube 7, which tube 18 is likewise arranged at a distance from the tube 7 and there is again a space between the two tubes. There is a decaying liquid that acts as a dielectric.

The fixed arrangement of the two tubes (7, 18) results in a capacitor having a constant volume ridge relative to each other. Furthermore, the cylindrical tube 18 acting as a pole is likewise insulated in the cylinder base 8 and can be connected via a lead 20 to a measured value receiver. Tubes 7 and 18 also form a tubular capacitor which serves for pressure and temperature compensation of the dielectric body, so that the manner of operation of the entire device is set up as a capacitive half-bridge.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a photographic damper in which a hollow piston rod forms a capacitor together with a hollow space, Fig. 2 is a sectional view schematically showing a cylinder capacitor, and Fig. 3 shows the piston stroke/capacity related to the cylinder capacitor. FIG. 4 is a sectional view showing another embodiment of an imaging damper in which the piston and the bottom of the cylinder are formed as a capacitor, and FIG. 5 shows a vibration damper in which the sleeve surface of the cylinder is formed as an induction coil. 6 is a sectional view showing a vibration damper with a coil arrangement, and FIG. 7 is a sectional view showing a vibration damper in which the tube with another cylindrical tube forms a second fixed capacitor. In the figure, 1 is a cylinder, 2 is a piston, 6 is a piston rod (first electrode), 4 is an internal space, 7 is a tube (second electrode), 16 is a cylinder bottom, 14 is an outer sleeve surface, 15
is a winding, 1i17 is two windings, IElj: other tube, 1
9 is the cylindrical internal space 0

Claims (1)

[Claims] (1) The piston is connected to at least one piston rod via the piston rod.
Hydraulic, pneumatic or hydropneumatic assemblies, such as gas springs and hydro-nitrogen springs, for vibration damping, arranged so as to be movable in one direction in a cylinder filled with one damping medium. In the piston stroke circumferential adjusting device consisting of: in the inner space of the cylinder, a first electric wire which moves in the axial direction is formed directly or indirectly by the piston and /''1. or the piston rod; A capacitor 75" JS screw 1 is connected to the capacitor 75" so that the first and second electrodes are held in position within the cylinder. A piston stroke adjusting device characterized in that the pistons are separated from each other by a dielectric material. (2) The first polarization is formed in the hollow space of the piston rod, and at this time, the first electrode is fixed to the bottom of the cylinder and is arranged at intervals as a second electrode in the hollow space of the F1 piston rod. 2. A piston stroke adjusting device as claimed in claim 1, wherein said first electrode is telescopically movable in relation to said second' electrode. (Claim 1) wherein the bottom of the cylinder is insulated and arranged in the cylinder as the two electrodes, and the side of the piston facing the bottom of the cylinder is formed as the first electrode. A device for adjusting the stroke of a piston according to claim 1, characterized in that: (4) the polarization of the capacitor is connected to a capacitance measuring bridge and generates a corresponding nuisance magnitude via an amplifier; The piston stroke adjustment device according to paragraph 5.(5) The cylindrical inner space of the tube fixed to the bottom of the cylinder is further provided with a tube fixedly arranged at a gap, and the other tube is the tube fixed to the bottom of the cylinder. The piston stroke adjustment device according to claim 2, characterized in that a capacitor with a fixed capacitance is formed as an additional electrode with the tube.(6) The tube and the other tube are insulated from each other. A piston stroke adjusting device according to claim 5, characterized in that the piston stroke adjusting device is disposed at the bottom of the cylinder. (A) The other pipe is similarly fixed to the bottom of the cylinder. The piston stroke adjusting device according to claim A11.
A piston stroke adjustment device consisting of a hydraulic, pneumatic or hydropneumatic assembly such as a vibration damper, a gas spring and a hydropneumatic spring, arranged axially movably in a cylinder filled with one damping medium. A device for regulating the stroke of a piston, characterized in that the outer sleeve surface of the cylinder has a winding that generates at least one magnetic field over the range of the piston stroke. (9) Two windings are provided, said windings being separated perpendicularly to the axis of rotation of said cylinder, the valley windings speeding up the retained piston stroke. The piston stroke rA adjusting device according to range 8.