EP-4737875-A2 - PRESSURE AND TEMPERATURE SENSOR

Abstract

An object is to provide a pressure and temperature sensor capable of precisely measuring a pressure. A sensor body 15, a diaphragm 21 defining an accommodation space R together with the sensor body 15, and a transmission substance S charged in the accommodation space R are provided, and a pressure measurement body 16 and a temperature measurement body 17 which is a separate body from the pressure measurement body 16 are disposed in the accommodation space R.

Inventors

• TAKAHASHI, KAZUHIRO
• OISHI, Keizo
• MATSUSHITA, Tadayoshi
• YAMAMOTO, KENTARO
• KOKITA, Hiroshi

Assignees

• Eagle Industry Co., Ltd.

Dates

Publication Date

20260506

Application Date

20211008

Claims (3)

1. A sensor comprising: a sensor body; a diaphragm defining an accommodation space together with the sensor body; a transmission substance charged in the accommodation space; a measurement body disposed in the accommodation space; and a spacer disposed in the accommodation space, wherein a through flow passage configured for charging the transmission substance into the accommodation space therethrough is provided across the sensor body and the spacer, and the through flow passage is defined collectively by a through hole provided to pass through the sensor body in an axial direction and a through hole provided to pass through the spacer in the axial direction.
2. The sensor according to claim 1, wherein the through hole of the spacer is provided in a thick width portion expanded to the inner diameter side of the spacer.
3. The sensor according to claim 1, wherein the spacer is formed in a cylindrical shape.

Description

{TECHNICAL FIELD} The present invention relates to a pressure and temperature sensor capable of measuring a pressure and a temperature of a fluid to be measured. {BACKGROUND ART} In various fields, a pressure and a temperature are utilized for operation, maintenance, etc. of devices, both the pressure and the temperature are often used, and a pressure and temperature sensor is utilized for responding to a demand to obtain the pressure and the temperature at the same time. The pressure and temperature sensor includes a pressure measurement body that outputs a pressure signal in accordance with a pressure of a fluid to be measured, and a temperature measurement body that outputs a temperature signal in accordance with a temperature of the fluid to be measured, and is capable of transmitting the pressure signal and the temperature signal to an external device. Regarding such a pressure and temperature sensor, the pressure measurement body and the temperature measurement body are arranged in the fluid to be measured, and sometimes chemically or mechanically influenced from the fluid to be measured and damaged. Therefore, an isolation type pressure and temperature sensor in which a pressure measurement body and a temperature measurement body are in indirect contact with a fluid to be measured is widely used. In the isolation type pressure and temperature sensor, for example, the pressure measurement body and the temperature measurement body are arranged in an accommodation space defined by a sensor body and a diaphragm, and a transmission substance is charged in the accommodation space. The pressure measurement body outputs a pressure signal in accordance with a pressure of the transmission substance which receives a pressure of the fluid to be measured via the diaphragm. The temperature measurement body outputs a temperature signal in accordance with a temperature of the transmission substance which receives a temperature of the fluid to be measured via the diaphragm. After that, the pressure signal and the temperature signal are converted into a pressure measurement value and a temperature measurement value by an integrated circuit, etc. provided in a substrate. In a pressure and temperature sensor shown in Patent Citation 1 serving as an example of such an isolation type pressure and temperature sensor, a sensor chip integrally including a pressure measurement body and a temperature measurement body is arranged in an accommodation space in which a transmission substance such as silicon oil is charged. The sensor chip is of a semiconductor diaphragm type including a bridge circuit. When a pressure is applied to the sensor chip, an intermediate voltage of the bridge circuit that functions as the pressure measurement body is changed, and the sensor chip outputs a pressure signal in accordance with this change. When a temperature of the sensor chip is changed, a voltage between both ends of the bridge circuit that functions as the temperature measurement body is changed, and the sensor chip outputs a temperature signal in accordance with this change. In such a way, in the pressure and temperature sensor as in Patent Citation 1, it is possible to measure the pressure and the temperature by the sensor chip integrally including the pressure measurement body and the temperature measurement body. Therefore, it is possible to downsize. However, since two types of measurement values are measured by the integrated sensor chip, a structure of the pressure and temperature sensor as in Patent Citation 1 is limited. Further, a pressure change of the transmission substance influences the temperature measurement body. Similarly, a temperature change of the transmission substance influences the pressure measurement body. Thereby, the pressure and temperature sensor as in Patent Citation 1 is not capable of measuring precise values by the respective measurement bodies. Therefore, with the pressure and temperature sensor as in Patent Citation 1, for example, it is difficult to make correction with an influence of the temperature over measurement of the pressure in accordance with the temperature signal. From this, the measured pressure measurement value and the measured temperature measurement value have poor precision. By the way, it is also possible to determine a relationship between the pressure and the temperature in advance by calibration, and obtain a precise pressure measurement value and a precise temperature measurement value. However, the sensor chip is manufactured by using a semiconductor process, and variation for each production lot is very large. Therefore, there is a problem that, since the sensor chip requires calibration for the pressure and the temperature for an individual object, it takes a lot of trouble. In a pressure and temperature sensor shown in Patent Citation 2 serving as another example of the pressure and temperature sensor, a pressure measurement body and a temperature measurement body are separat