JPS6214024A - Hydraulic type pressure detecting body - 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 method in which a compressible liquid is loadable by external pressure.
The present invention relates to a hydraulic pressure sensing body of the type which is present in a resilient case which is tubular and connectable with at least one pressure gauge or transducer.

The applicant has already known a hydraulic pressure sensor of the above-mentioned type, which is extremely long and can be loaded with pressure at any position on its case jacket. Differences in relative measurements of the same pressure at different positions of the elastic pressure sensor housing are ignored. In order to perform detection in this hydraulic pressure detector, a rigid tube is provided at least approximately in the center inside the tubular pressure detector case in the longitudinal direction of the pressure detector case. The jacket of the tube defines, together with the inner wall of the case, a circumferential gap which is closed on both end sides, the inner tube being connected at one end to a pressure gauge or transducer and distributed over the entire length of the tube. It has multiple radial holes.

It has been found that in this hydraulic pressure sensor, irregularities caused by differences in the fluids transmitting pressure are eliminated.

This is because the hydraulic pressure measurement no longer takes place in the elastic pressure sensor housing, but rather in the rigid inner tube. In combination with the above, the ever decreasing wave energy within the inner tube is provided with an energy pulse that compensates for the energy loss at each position of the radial bore. Moreover, it has been found that almost point-like loads at different positions of the elastic pressure sensor housing lead to differences in the relative measured values of the same pressure.

In view of the above, the present invention enables pressure to be applied pointwise to a known hydraulic pressure sensor at any position on its case jacket, and in this case, there is no difference in relative measured values of the same pressure. The challenge is to configure it so that there are no errors.

This object is achieved according to the invention by configuring the pressure-sensing wall of the tubular case to be in contact with a pressure-transmitting longitudinal reinforcement.

When the elastic pressure sensor housing is subjected to a point-like external pressure, this longitudinal stiffener allows a wide, virtually lossless pressure distribution to be achieved inside the housing and so that in practice there is always an equal relative pressure distribution. Measured values can be obtained. This is achieved with a simple construction without the provision of a rigid inner tube.

A very optimal configuration for the use of this type of hydraulic pressure sensor for highly precise devices is a special embodiment of the pressure sensor according to the invention in which at least approximately A rigid tube is extended in the center and in the longitudinal direction of the case, and the jacket of this tube defines a circumference 1fjJ1 that is closed on both end surfaces together with the inner wall of the case, in which case the inner tube has at least This is achieved by forming a number of radial holes at one end forming a connection to a pressure gauge or transducer and distributed over the entire length of the tube.

An advantageous embodiment of the pressure sensor according to the invention is such that the longitudinal reinforcement is constructed as an elastic band, which rests on the inside or outside of the wall for pressure sensing of the housing; Alternatively, the longitudinal reinforcement is designed as an external U-shaped profile which surrounds the wall for pressure sensing as well as parts of the continuous side walls of the housing.

In order to support such a pressure sensor immovably, it is advantageous to insert the tubular housing in its longitudinal extension into a U-shaped profile on the bottom side.

The invention furthermore relates to the use of a hydraulic pressure sensor according to the invention in scales or tread mats by arranging a plurality of such pressure sensors in parallel to one another, which can be connected to an evaluation device. .

The use in a scale is achieved by means of two pressure sensing bodies arranged in parallel and spaced from each other, carrying a scale plate and each connected at both ends with a pressure difference measuring circuit.

The invention will now be described in detail with reference to the embodiments illustrated in the accompanying drawings.

The known pressure sensing body, clearly illustrated in FIG.
It has an elastic outer tube body 1 with a working length of Ocm or more.

The cross section of this tube l may be formed arbitrarily.

The inner diameter of this pressure detection tube l is, for example, 10 x 20 mm.

Approximately in the center of the interior of the tubular case 1 and in the longitudinal direction of the case extends a rigid tube 2 made of a suitable material, for example aluminum. In this case, the outer jacket of this inner tube 2 and the inner wall of the housing I delimit a peripheral gap 3, which is closed at both ends by the end faces 5 and 6 of the tubular housing I. in this case,
The ends 8 and IO are connected in a fluid-tight manner to said end face 5 or 6 in a suitable manner. Furthermore, the inner tube 2 carries at its connecting end 8 a suitable connecting element 9, which advantageously passes through the corresponding end face 5 of the housing 1.

By means of this coupling element 9, the inner tube 2 can be connected to pressure display means or evaluation devices or signal converters or similar equipment, which are not shown in detail here. The inner tube I is closed in a pressure-tight manner at its other end 10, through which an exhaust screw 7 passes through the end face of the inner tube. This vent screw allows for proper venting of the entire system. The diameter of the inner tube 2 is relatively small compared to the inner diameter of the case 1, and in this example has an outer diameter of 5 mm and an inner diameter of 4II11, for example.

The inner tube 2 is provided with a number of radial holes 4. These radial holes 4 have a nozzle-like diameter of, for example, IIIm in this embodiment and are distributed over the entire length of the inner tube 2.

The entire system described above is filled with a compressible liquid, for example water, and optionally with antifreeze additives, in order to increase the pressure resistance of the especially elastic pressure sensor case l.
It is under a preload of, for example, 0.7 bar from Ol.

With such known systems, the measurement accuracy can be increased several times over other known systems, and the scope of application of such systems is thereby also significantly expanded. It is possible, but it does not meet all the requirements.

In particular, the possibility of achieving results comparable to simple structures,
Alternatively, there must be a possibility that an optimal configuration can be achieved by combining it with the above-mentioned inner tube.

For this purpose, as shown in FIGS. 2 and 3, the pressure-sensing wall l' of the tubular case 1 is constructed in such a way that it is in contact with a pressure-transmitting longitudinal reinforcement 11 or 11'. be done.

This longitudinal reinforcement is an elastic steel strip 11 which abuts on the inside of the wall l' for pressure detection of the case l, as shown in FIG. This elastic steel strip can be joined to the wall l' by vulcanization or a similar process.

However, it is possible to install an elastic steel strip 11 on the outside, or to surround the wall 1' for pressure detection and the connected side wall part of the case 1 as a longitudinal reinforcement as shown in FIG. It is also possible to provide an outer U-shaped formation 11' that has a radial shape.

All arrangements are possible in combination with the inner tube 2.

In order to achieve an optimal framing of such a pressure sensor case l, this pressure sensor case is mounted in its longitudinal extension in a U-formation 12 on the bottom side, as shown in FIG. being surrounded.

If the above-mentioned inner tube is not provided, the pressure sensor housing 1 is provided at its end with connection means for a pressure indicating means in a suitable manner per se. There is no need to explain this configuration in detail here. This is because this configuration is considered publicly known.

As is well known, in this case as well, a foot mat 13 provided with a large number of the above-mentioned hydraulic pressure sensing bodies is laid down,
By connecting the whole to a suitable evaluation device, it is possible, for example, to precisely measure and record the course of movement when walking on this stepping mat, thereby providing diagnostic means for orthopedics.

Thus, another use for hydraulic pressure sensing bodies is in scales, which is clearly shown in FIG. In this case, scale plate 1
It comprises two parallel pressure sensing bodies l, which are spaced apart from each other and carrying a pressure sensing element 3', each of which is connected at its end to a pressure difference measuring circuit 14.

Such scales are suitable for all types of loads and stresses and are very precise for a very simple construction.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a known hydraulic pressure sensor shown in perspective view; FIG. 2 is a partial perspective view of a first embodiment of the hydraulic pressure sensor according to the invention; FIG. 3 is a perspective view of a first embodiment of the hydraulic pressure sensor according to the invention. A cross-sectional view of another embodiment of the hydraulic pressure detector; FIG. 4 is an arrangement diagram of the device according to FIG. 2 when used as a scale; The symbols in the figure are: l...Case 1'...Wall

Claims (1)

Claims: 1) Hydraulic type in which the compressible liquid is present in an elastic case which is tubular and connectable with at least one pressure gauge or transducer, which can be loaded by external pressure. The pressure sensing body is characterized in that the pressure sensing wall (1') of the tubular case (1) is configured to be in contact with pressure transmitting longitudinal reinforcements (11, 11'). A hydraulic pressure sensing body. 2) Inside the tubular case (1), a rigid tubular body (2) extends at least approximately in the center and in the longitudinal direction of the case, and the jacket of this tubular body extends along the inner wall of the case and both end faces (5, 6), which defines a peripheral gap (3) closed at 6), in which case the inner tube (2) is arranged at least at one end (8) to serve for connection with a pressure gauge or transducer; Hydraulic pressure sensing body according to claim 1, characterized in that it has a plurality of radial holes (4) distributed over the length of the tube. 3) The longitudinal reinforcement (11) is an elastic steel strip that abuts on the inside or outside of the wall (1') for pressure detection of the case (1). The hydraulic pressure sensing body according to item 1. 4) The patent claim in which the longitudinal reinforcement (11') is an external U-shaped configuration surrounding the wall (1') for pressure detection as well as the connected side wall part of the case (1). The hydraulic pressure sensing body according to item 1. 5) Hydraulic pressure sensor according to claim 3, wherein the tubular case (1) is surrounded in its longitudinal extension in a U-shaped configuration (12) on the bottom side. 6) Pressure in a tubular case (1) in such a way that the compressible liquid is present in an elastic case loadable by external pressure, which is tubular and connectable with at least one pressure gauge or transducer. characterized in that a hydraulic pressure sensing body is used as a scale, in which the sensing wall (1') is configured in such a way that it is in contact with the pressure-transmitting longitudinal reinforcement (11, 11'), Use of hydraulic pressure detectors. 7) Pressure difference-measuring circuit (14) at each end
Hydraulic pressure sensing according to claim 6, using two parallel pressure sensing bodies spaced from each other and carrying a horizontal scale plate (13'), which are connected to a horizontal scale plate (13'). use of the body. 8) Pressure in a tubular case (1) in such a way that the compressible liquid is present in an elastic case loadable by external pressure, which is tubular and connectable with at least one pressure gauge or transducer. A number of hydraulic pressure sensing bodies, which can be combined with the evaluation device, are arranged in such a way that the sensing walls (1') are in contact with the pressure-transmitting longitudinal reinforcements (11, 11'). Use of a hydraulic pressure detector characterized in that such pressure detectors are arranged in parallel and used as a stepping mat.