Weight and pressure measuring device

A weight and pressure measuring device, comprising a fluid filled cushion pad of limited volume, connected to a pressure indicator to measure the pressure produced during pressure loading. Such a measuring device requires little space, is lightweight, and can easily be transported and used. A blood pressure and weight measuring device has an inflatable sleeve which is connected through a tube connection, with a pump device and a pressure measuring device. In order to measure blood pressure as well as weight, by means of such a measuring device, a second inflatable device, with a limited volume, is connected with the pressure measuring device and the pump device. The device measures the pressure produced by the weight load, which is proportional to the weight being determined.

BACKGROUND OF THE INVENTION 
The invention relates to a weight and pressure measuring device. 
It is known that there is frequently a relation between blood pressure and 
weight. During regular examinations of blood pressure, it is therefore 
highly desirable to also check the weight. 
THE PRIOR ART 
Various weight measuring devices are known which operate in accordance with 
various measuring principles, such as, for example, devices in which a 
comparison of the weights is carried out with scale units, or devices in 
which the weight force is measured, for example, with spring-type scales. 
OBJECTS OF THE INVENTION 
The object of the present invention is to provide a weight and pressure 
measuring device having low space requirements, light weight, and which is 
easy to transport and use. 
A further object is to provide a measuring device by which both blood 
pressure and weight can be measured in a simple and easy manner. The 
measuring device should be easy to transport and use anywhere, without 
difficulty. 
THE INVENTION 
The measuring device in accordance with the invention has the advantage 
that it fits, within travelling luggage, and handbags or similar 
containers, and can therefore be used at any time, independently of 
location. The measuring device can also be used as a small scale and, in 
modified form, as a large scale for heavier weights. 
The measuring device may be advantageously used by high-blood pressure 
patients, who must continuously check both blood pressure and weight, a 
considerable convenience, particularly during longer trips. Both 
measurements can therefore be carried out reliably and independently of 
location. The measuring device is light in weight, and requires little 
space, so that it can be carried within travelling luggage easily and 
without problem.

DETAILED DESCRIPTION 
FIG. 1 illustrates a weight and pressure measuring device 2 with a 
container 4 which has a closed or limited volume, and can be filled with 
fluid, i.e. gas or liquid. The container 4 may be a cushion pad connected 
by means of a tube 6, with a manometer 10, as well as with a pump device 
12 for inflating the cushion pad 4 and for releasing the pressure. The 
cushion pad 4 may be provided with a stepping pad 9 which can be rolled 
up, in order to increase the solidity of the support for the object to be 
weighed. The pumping device 12 is preferably provided with a zero point 
indicator 14 for the zero point adjustment of the manometer. The indicator 
may be a scale, marker, gauge or the like, for reading the 
pressure-weight, and which can be set at zero. 
The zero point adjustment can be made by inflating device 10 until the 
pressure measuring indicator reaches a predetermined zero mark. 
The manometer scale can be directly calibrated in weight indicia. When the 
cushion pad 4 is loaded with the weight of a person, the manometer 10 
reacts to the pressure thereby produced. The weight, which is proportional 
to the pressure produced, can be read directly off the manometer scale. 
The device 12 preferably consists of an air pump. The cushion pad 4 can be 
filled with a liquid or partially filled with a liquid and partially with 
air or another gas. A partial filling with liquid and with gas provides 
the advantage that the pressure can be measured in the gas portion, which, 
from the viewpoint of stability, is of particular advantage. 
Apart from pressure measuring devices which operate purely mechanically, 
electro-mechanical transformers can also be used, which employ, for 
example, changes in capacitance or resistance in order to measure the 
pressure or weight. 
The application of the principle of capacitance change is depicted in 
figure 2. Two conductive foils, between which a compressible dielectric 24 
is located, are used as condenser plates 20, 22. A stepping pad 26 of 
electrically insulating material is placed on the upper foil 20 which 
ensures that the compression of the dielectric takes place in a uniform 
manner if the lower foil 22 is placed on an even surface. Through the 
compression of the dielectric due to loading, the capacitance changes, 
which change can be measured on the measuring gauge 28, and which provides 
a measurement for the weight load. The measuring device in FIG. 2 can be 
selected from a very wide range of scales which are economical in weight 
and space as well as transportable. Apart from individual and small 
scales, large-surface transportable scales can also be used which can be 
applied anywhere, rapidly and without great expense. In the framework of 
traffic inspections, for example, a foil field may be spread out on a 
highway. The weight of vehicles passing over it can be indicated directly, 
so that it can be immediately determined whether or not the vehicle is 
overloaded. Such a measuring device also makes it possible to determine 
weights or forces at different locations, and on large surfaces. 
For the second principle of measurement (change in resistance), which is 
not depicted here, a second, closed gas-filled system can be provided in 
communication with a closed, gas-filled system. When the first, external 
system is loaded with a weight, the pressure in its interior rises. 
Through this means, the volume of the second system is reduced. This 
mechanical change can be conveyed to an electrical variable resistor, 
whereby the change in resistance represents a proportional change in the 
weight load. The external system can also be filled with liquid, instead 
of with gas. 
FIG. 3 of the diagram schematically depicts a measuring device 2' with an 
inflatable sleeve 4' for blood pressure measurement, which is connected, 
through a tube 6' and plug connection 8', with a pressure measuring device 
10' and a pump device 12', which has a complementary interconnecting plug 
connection 14'. The pump device is equipped with a zero point indicator 
16'. The zero point adjustment can take place, for example, with a spring 
bar and a calibration mark. The indicator may be a scale, marker, gauge or 
the like, which canb e set at zero, for reading the weight. Instead of the 
spring bar, a helical torsion spring (not depicted) can be used. 
The zero point adjustment can, however, also take place simply by inflating 
the device sufficiently to cause the pressure measuring gauge to reach the 
zero mark, which can be predetermined. 
The measuring device 2' furthermore has an inflatable cushion pad 18, 
which, through tube 20' with a plug connection 22', can be connected with 
the pressure measuring device 10' and the pump device 12'. 
The pressure measuring device 10' includes a scale 24' with a lower 
measuring range for blood pressure measurements, and an upper range for 
weight measurements. A stepping pad 26' which can be rolled up may be 
placed on the cushion pad 18'. The manner of operation of the measuring 
device in accordance with FIG. 3 is as follows: 
By means of the pressure measuring device 10', the pump device 12' and the 
sleeve 4', the blood pressure, which is read on the low range scale of the 
pressure measuring device, is measured in the conventional manner. Then 
the tube 6' of the sleeve is released from the pump device 12' and, in its 
place, the cushion pad 18, with the tube 20', is connected to the pump 
device 12' by means of plug 22. The cushion pad is then inflated until the 
zero point adjustment has taken place. After that, the stepping pad is 
unrolled onto the cushion pad, on which an individual may then be placed 
for weight measurement. The weight can then be read off the upper range 
portion of the scale of the pressure measuring device. 
FIG. 4 of the diagram schematically depicts a measuring device 2', which 
has an inflatable sleeve 4' for blood pressure measurement, equipped with 
a tube 6' with a plug connection 8'. The measuring device 2' furthermore 
has a pressure measuring device 10', a pump device 12' for inflating and 
relieving the pressure, having two interchangeable plugconnections 14' and 
15', an inflatable cushion pad 18' with a tube 20' and a plug connector 
22'. A stepping pad 26' may be placed onto the cushion pad. A pressure 
reducing device 30' with two plug connections 32', 34', equipped with a 
zero point indicator 36' may be connected to measuring means 10' and to 
fitting 15' of the pump 12' when said pump is connected to the pad 18 at 
fitting 22'. 
The zero point indication or adjustment can take place in the manner of 
execution in accordance with FIG. 3. 
The pressure measuring device 10' has two scales 38', 40', one of which 
serves for measuring blood pressure, and the other of which serves for 
measuring the weight. 
The manner of operation of the measuring device in accordance with FIG. 4 
is as follows: 
By means of the interconnected pressure measuring device 10', the pump 
device 12' and the sleeve 4', the blood pressure, which can be read off 
one of the two scales of the pressure measuring device, is measured in the 
conventional manner. Then, the pressure measuring device 10' is 
disconnected from the pump device and the pressure reducing unit 30' is 
connected with the pump device and the device 10'. The inflatable cushion 
pad 18' is connected to the other end of the pump device. Then, the 
cushion pad is inflated until the zero point adjustment has taken place. 
After the stepping pad 26' has been placed on the cushion pad, a person 
can step onto the cushion pad, and the weight of the person can be read 
directly off the second scale of the measuring device 10'. 
Apart from pressure measuring devices operating in a purely mechanical 
manner, electro-mechanical transformer, which use, for example, changes of 
capacitance or changes of resistance for the pressure or weight measuring, 
may also be used. 
In the first case, two conducting foils, between which a slightly 
compressible dielectric is positioned, may be used. This arrangement is 
used in a closed, gas-filled system. If this system is loaded with a 
weight, the resulting volume change of the dielectric leads to a change in 
capacitance, which can be measured, and serves as a measure for the 
porportional weight load. 
For the second measuring principle, a second, closed gas-filled system is 
provided within a closed, gas-filled system. When the first external 
system is loaded with a weight, the pressure increases in its interior. By 
this means, the volume of the second system is reduced. This mechanical 
change can be communicated to an electrical variable resistor, which 
senses the change in resistance which is proportional to the weight load. 
The external system can also be filled with liquid instead of with gas. 
One advantage of the electro-mechanical transformer consists in the fact 
that a savings in weight and space is made possible, relative to 
mechanical systems.