CZ2007721A3 - Weighing apparatus, particularly apparatus for measuring weight of persons - Google Patents

Abstract

The device is provided with a washer (1) connected to the display (3), wherein the washer (1) is flexible and consists of a fabric provided with at least one capacitive sensor consisting of an inner electrode (14) and an outer electrode (13) arranged between a dielectric (15), wherein the outer contour of the inner electrode (14), the outer electrode (13) and the dielectric (15) is equal to or less than the outer contour of the substrate (1).

Description

BACKGROUND OF THE INVENTION The present invention relates to a weighing device, in particular to measuring the weight of a person, provided with a pad connected to a display.

BACKGROUND OF THE INVENTION

Previously known weighing devices use a rigid pad, by means of which the resulting gravitational force is transmitted to the resilient member. From the deformation of this member the magnitude of the applied force is then determined. This applies to both personal and transport weights, for example for measuring axle pressures. The design of the flexible members and their number varies according to the purpose of the weighing device. The measured force is then electrically evaluated and converted to a mass numerical value. These cannons are also diverse and can only be used for the specific equipment to which they are intended.

A disadvantage of the above solutions is, in particular, the fact that none of them is applicable to the measurement of the weight on the flexible substrate. Another disadvantage is that none of the existing wiring is able to evaluate measurements on a flexible substrate.

Weighing devices are also known which use a rigid pad for weighing, under which an inflatable bag or flexible plate is placed, which acts on an incompressible fluid, the pressure of which is sensed by a pressure sensor with an electrical output to a mass-converted evaluator.

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The disadvantage of these axle-pressure measuring devices is, in particular, the robustness of their construction, which, even if eventually reduced for measuring the weight of persons and for indoor use, has a relatively high weight for mobile use. Another drawback is the difficulty of maintaining a defined pressure in the air bag or maintaining a constant liquid charge.

It is an object of the invention to solve the above problems so that it is possible to measure the weight on a flexible backing, for example on a home or other fabric.

SUMMARY OF THE INVENTION

The above-mentioned drawbacks are largely eliminated by the weighing device according to the invention, which is characterized in that the substrate is flexible and consists of a textile provided with at least one capacitive sensor consisting of an internal electrode and an external electrode with a dielectric arranged between them. the contour of the inner electrode, the outer electrode, and the dielectric is equal to or smaller than the outer contour of the pad. The dielectric may consist of a 1 to 3 mm thick layer of expanded polyethylene, wherein the inner electrode and the outer electrode may consist of a metal fabric or metal foil or other conductive material. The substrate may be provided with one internal electrode to which one dielectric layer and one external electrode are assigned on each side.

Each outer electrode lead and internal electrode lead are connected to the display via the transmitter electronic circuit. The backing may be provided on its top and bottom surfaces with a protective dielectric layer, consisting of a woven or knitted fabric or a polyethylene foam, the backing being then a mat or rug or rug.

An advantage of the present invention is the provision of all personal weight requirements for measuring the weight of a person. Another advantage is the simplicity of the construction of the device, which results in high reliability and low purchase price. The universality of the device principle makes it possible, for example, to make it as a bed for measuring the weight of immobile patients and the like.

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Overview of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in more detail in the accompanying drawings, in which: FIG. 1 shows a shim in a side section and FIG. 2 shows a block diagram of a display converter.

DETAILED DESCRIPTION OF THE INVENTION

In Fig. 1 there is a pad 1 comprising an inner electrode 14 with an outlet 12, to which a dielectric 15 made of foam polyethylene adjoins on each side and an outer electrode 13 with an outlet 11 on each side.

In Fig. 2 there is a converter 2 with pulse generators 21 formed by astable flip-flops connected and connected to terminals 11 and 12. Pulse generators 21 are further connected via monostable circuit 22 and pulse counter 23 to the inverter 24, to which output 3 is connected to display 3.

The function of the device is that after loading of the pad 1 by a person wishing to measure its weight, the capacity of the capacitive sensor formed by the dielectric 15 arranged between the outer electrode 13 and the inner electrode 14 is changed by pressing any measuring point on the pad 1. the capacitor and display 3 will show the measured value because the converter 2 converts the capacity change to a number.

All parts of converter 2 operate in a standard manner. The frequencies of the pulse generators 21 are selected such that at full load of the capacitive sensor described, the full state of the 8-bit pulse counter 23 is read. To eliminate parasitic effects such as electrical interference or capacitance changes near objects 1, two capacitive sensors according to an exemplary embodiment,

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which have a common internal electrode 14 and two electrically connected external electrodes 13. The sensitivity of the sensor will not increase, but measuring the same relative change at a higher base capacity value will increase the signal-to-noise ratio.

In the context of the invention, the mat 1 can be designed, for example, as a bedding for measuring the weight of a sitting or lying person, since the device makes it possible to measure the magnitude of the applied force regardless of its distribution on the surface.

Industrial applicability

The weighing device according to the invention can be used for measuring the weight of persons on a support made up of soft furnishings and accessories, in particular rugs, rugs, mats or the like.

Claims (5)

Apparatus for weighing, in particular measuring the weight of persons, having a substrate connected to a display, characterized in that the substrate (1) is flexible and consists of a textile provided with at least one capacitive sensor comprising an internal electrode (14) and an external electrode (13). ) between which a dielectric (15) is arranged, wherein the outer contour of the inner electrode (14), the outer electrode (13) and the dielectric (15) is equal to or smaller than the outer contour of the substrate (1). Device according to Claim 1, characterized in that the dielectric (15) is formed 1 to 3 mm of a thick layer of foamed polyethylene, the inner electrode (14) and the outer electrode (13) being a metal fabric or metal foil or other conductive material. Device according to claim 2, characterized in that the substrate (1) is provided with one internal electrode (14) to which one layer of dielectric (15) and one external electrode (13) are associated on each side. Device according to claim 1 or 3, characterized in that the outlet (11) of each outer electrode (13) and the outlet (12) of the inner electrode (14) are connected to the display (3) via the electronic circuit of the converter (2). Device according to claim 1 or 4, characterized in that the substrate (1) is provided on its upper and lower surfaces with a protective dielectric layer (16) consisting of a woven or knitted fabric or polyethylene foam, the substrate (1) being a mat. or rug or rug.