JP3803854B2 - Contact pressure calibration method - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a calibration method for a contact pressure measuring device on a flexible surface, which is a body pressure measuring device when a body is placed in a chair, a bed, etc., a pressure measuring device when wearing clothes, a biological treatment and care. The present invention relates to a calibration method that serves as a reference for confirming accuracy and reproducibility of a device that measures binding force and palpation force.
[0002]
[Prior art]
Conventionally, as a method of calibrating the contact pressure of a flexible surface, there has been a method in which a pressure sensor is horizontally submerged in a liquid, a plane pressure is applied, the depth is measured, and the product is confirmed by the product with the specific gravity of the liquid. The liquid mainly uses water or mercury. For example, when water is used, there is a limit because the height of the water column is required at high pressure. Moreover, when mercury with a large specific gravity was used, it was not easy to secure environmental problems and quantity. These were flat calibrations, and the actual measurement objects were many living organisms, most of them were soft and curved, and the surface was deformed as the pressure was changed.
As another method, there is a method in which a pressure receiving sensor is placed in a sealed container / chamber that can adjust the pressure, and the pressure in the container is adjusted and calibrated. This method is a three-dimensional calibration because the pressure is applied from all sides, and it is difficult to say that the surface contact pressure is calibrated. This method was originally performed with a strain gauge sensor for the purpose of measuring fluid pressure.
As another method, there is a method in which a weight is placed on the pressure sensor and the weight is divided by the contact area. However, it is a vertical load to the last, and is a method that is difficult to apply to curved surfaces and flexible surfaces. Further, in the method of pressing with an air bag and using the pressure value in the bag, the material tension of the bag works, and the pressure is not necessarily the contact pressure due to the influence of the characteristics.
[0003]
[Problems to be solved by the invention]
Therefore, the standards were not established internationally, and each measurement device manufacturer calibrated independently, so the measured values differed for each device. There was a strong demand for calibrated measurement values from researchers in the medical, welfare, nursing, rehabilitation, and clothing fields that require common equipment, but this did not help.
The present invention is a method for calibrating the contact pressure of a flexible surface, and reproduces the complex situation where the surface pressure is changed along with the change in the pressure, flexibility, elasticity, and physical properties of the curved surface. There was a need to establish a calibration method that can confirm whether or not.
[0004]
[Means for Solving the Problems]
As a configuration, the pressure is transmitted to the surface to be measured 8 through the flexible bag 2 or the flexible membrane 5 inside the container 1 and the pressure inside the container 1 is increased, thereby transmitting the surface pressure. Moreover, since the volume of the flexible bag 2 or the container 1 and the flexible membrane 5 is larger than that before the contact with the measurement surface 6, the material tension of the flexible bag 2 and the container 1 and the flexible membrane 5 is not affected. It is transmitted to the surface to be measured 6 as surface pressure.
[0005]
[Action]
When the surface 8 to be measured is a flexible object, the surface pressure is deformed by receiving pressure, and the large flexible bag 2 or the loose flexible film 5 is not deformed by their material tension. Close contact with. That is, the volume A in the unloaded state in the container 1 is larger than the volume B in the state in which the surface to be measured 8 is installed, pressurized and subjected to surface pressure, when the flexible bag 2 and the flexible membrane 5 are inflated. It will not be affected by the material tension.
Therefore, the pressure inside the container 1 is measured by pressurization, and the flexible bag 2 or the flexible membrane 5 transmits the surface pressure as the surface pressure to the surface to be measured 8 so that the contact pressure can be known. At this time, the flexibility of the flexible bag 2 and the flexible film 5 is a repulsive stress and a transmission error occurs. However, increasing the flexibility leads to high accuracy and high sensitivity. Therefore, the surface pressure and the contact pressure can be controlled and calibrated by adjusting the internal pressure of the container 1 by the pressurization adjusting device 4.
[0006]
【Example】
As an embodiment of the present invention, in FIG. 1, a flexible bag 2 having a volume larger than that of the container 1 is provided inside the container 1, and a fluid 3 whose pressure is controlled by a pressure adjusting device 4 is contained in the flexible bag 2. The inside of the flexible bag 1 is measured with a pressure gauge 7. In FIG. 6, a surface 8 to be measured is placed, a pressure sensor 9 of a contact pressure gauge is installed on the surface, and the adjustment pressurizing devices 4 and 12 are pressurized in the flexible bag 2 by the fine pressure adjusting device. Thus, a surface pressure can be applied to the surface 8 to be measured. If the surface to be measured 8 is a flexible body, the flexible bag 2 keeps in close contact with the surface to be measured 8 which is deformed with pressure, and the surface pressure is not affected by the material tension as long as the volume of the flexible bag 2 has a margin. You can hang it.
Therefore, by installing the pressure sensor 9 of the contact pressure gauge on the surface of the surface to be measured 8, a comparison is made between the pressure signal value of the pressure sensor 9 and the reference pressure gauge 7, and each reference error is taken into consideration. Can be proofread.
2 and 4, in the embodiment in which the surface of the container 1 where the surface to be measured 8 is located is opened, the surface to be measured 8 that does not fit in the container 1 as shown in FIG. In the case of the measurement target surface 8 that cannot be moved, the calibration is performed by moving the calibration device itself. 3 and 4 show an embodiment in which the same condition is satisfied by the flexible membrane 5 instead of the flexible bag 1. FIG. 5 is an embodiment in which the peripheral wall of the container 1 is a movable wall 10 so as to be able to closely adhere to the contact curved surface in FIGS. 2 and 4, and the flexible bag is formed on the open surface of the container 1 as shown in FIG. 7. This is an example in which the surface to be measured 8 is closely attached to the outer surface of No. 2. In this case, when the container 1 and the surface to be measured 8 are brought into close contact with each other, the case where the surface to be measured 8 is made of a flexible material and does not come into close contact due to deformation is an example performed on the movable wall 10.
Further, by measuring the temperature near the surface to be measured and correcting the pressure value and the thermal effect of the fluid 3, highly accurate calibration can be performed. A safety valve 13 is provided, and the pressure adjusting devices 4 and 12 are opened safely when the fine pressure adjusting device fails to prevent the container 1 and the like from being destroyed and are safely provided.
[0007]
【The invention's effect】
According to the present invention, since the flexible bag 2 having a volume larger than that of the container 1 or the container 1 and the flexible film 5 is required, a pressure substantially equal to the pressure applied to the inside of the container 1 is applied to the surface to be measured 8 as a surface pressure. I can press. That is, by adjusting the internal pressure of the container 1, the contact pressure of the curved surface and the flexible body can be known.
Therefore, it is possible to know the reproducibility of the curved surface, contact pressure gauge of flexible body, confirmation of accuracy, deformation against external pressure, relaxation, etc., and it can be expected that it will lead to improvement of those measuring instruments and international measurement standardization etc. . Also, change the external pressure over time, clarify the relaxed state, deformation, softness characteristics, etc. of the soft measurement surface 8, quantify the external pressure on the skin surface of the living body, organs, etc. This is an interesting contact pressure calibration method that opens up the prospect of care and education.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of the structure of the present invention. FIG. 2 is a cross-sectional view of one side of the container of the present invention. FIG. 3 is a cross-sectional view of a single side of the container of the present invention. FIG. 5 is a cross-sectional view with a movable wall of the present invention. FIG. 6 is a cross-sectional view of an embodiment of the present invention. Sectional view of opened embodiment [Explanation of symbols]
1 is a container 2 is a flexible bag 3 is a fluid 4 is a pressure adjustment device 5 is a flexible membrane 6 is an open lid 7 is a pressure gauge 8 is a surface to be measured 9 is a pressure sensor 10 is a movable wall 11 is a thermometer 12 is a slight pressure adjustment In the device 13, the safety valve A has a volume B before the measurement surface is installed.

Claims (8)

(A) A flexible bag 2 having a volume larger than that of the container 1 is provided in the container 1 provided with the open lid 6 so as to be in contact with the surface to be measured 8 without material tension.
(B) The fluid 3 flows into the flexible bag 2 through the pressure adjusting device 4.
(C) A pressure sensor 9 of a contact pressure gauge to be calibrated is installed on the surface to be measured 8, and the pressure in the flexible bag 1 is measured by the pressure gauge 7 of the fluid 3 whose pressure is controlled by the pressure adjusting device 4.
The contact pressure calibration method configured as described above. The contact pressure calibration method according to claim 1, wherein the surface of the container 1 where the surface to be measured 8 is located is opened so that the measurement surface 8 that does not fit in the container 1 can be accommodated and the apparatus can be moved . The contact pressure calibration method according to claim 1, wherein the same condition can be satisfied even if the flexible bag 2 is replaced with a flexible membrane 5 . The contact pressure calibration method according to claim 2, comprising a movable wall 10 that compensates for close contact between the container 1 and the peripheral wall of the surface to be measured 8 . The contact pressure calibration method according to claim 1, further comprising a thermometer for measuring the temperature in the container. The contact pressure calibration method according to claim 1, further comprising a fine pressure adjusting device 12 in the container 1. The contact pressure calibration method according to claim 1, wherein the container 1 is provided with a safety valve 13 . The contact pressure calibration method according to claim 1, wherein the open lid can be detached and the pressure sensor can be positioned between the flexible bag and the surface to be measured .

Images