JP-7855306-B2 - Pressure and temperature sensor

Inventors

• 松下 忠由
• 山本 健太郎
• 高橋 一宏
• 大石 恵三
• 小北 浩志

Assignees

• イーグル工業株式会社
• 株式会社バルコム

Dates

Publication Date

20260508

Application Date

20250421

Priority Date

20201020

Claims (2)

1. Sensor body and A diaphragm that defines the housing space together with the aforementioned sensor body, The transmission material filling the aforementioned containment space, Equipped with, The aforementioned containment space contains a measuring object and a cylindrical spacer. A through-channel is formed across the sensor body and the spacer for injecting the transmission material into the housing space. The through-flow channel is formed by a through-hole that penetrates the sensor body in the axial direction and a through-hole that penetrates the peripheral wall of the spacer in the axial direction .
2. The sensor according to claim 1, wherein the through hole of the spacer is formed in the thickened portion that bulges outwards on the inner diameter side of the spacer .

Description

This invention relates to a pressure-temperature sensor capable of measuring the pressure and temperature of a fluid under test. Pressure and temperature are used in various fields for equipment operation, maintenance, and other purposes. Often, both pressure and temperature are used simultaneously, and pressure-temperature sensors are employed to meet the demand for obtaining both pressure and temperature at the same time. A pressure-temperature sensor comprises a pressure measuring element that outputs a pressure signal corresponding to the pressure of the fluid being measured, and a temperature measuring element that outputs a temperature signal corresponding to the temperature of the fluid being measured. It is capable of transmitting both the pressure and temperature signals to external devices. Such pressure and temperature sensors, where the pressure and temperature sensors are placed within the fluid being measured, can be damaged by chemical and mechanical influences from the fluid. Therefore, isolated pressure and temperature sensors, where the pressure and temperature sensors are indirectly in contact with the fluid being measured, are widely used. In an isolated pressure and temperature sensor, for example, a pressure measuring element and a temperature measuring element are placed within a housing space defined by a sensor body and a diaphragm, and a transmitting element is filled within the housing space. The pressure measuring element outputs a pressure signal corresponding to the pressure of the transmitting element, which is received via the diaphragm from the pressure of the fluid being measured. The temperature measuring element outputs a temperature signal corresponding to the temperature of the transmitting element, which is received via the diaphragm from the temperature of the fluid being measured. Subsequently, the pressure and temperature signals are converted into pressure and temperature values by an integrated circuit or the like provided on the substrate. An example of such an isolated pressure-temperature sensor, as shown in Patent Document 1, is a sensor chip that integrates a pressure measuring element and a temperature measuring element within a housing filled with a transmitting material such as silicone oil. The sensor chip is a semiconductor diaphragm type equipped with a bridge circuit. When pressure is applied to the sensor chip, the intermediate voltage of the bridge circuit, which functions as the pressure measuring element, changes, and the sensor chip outputs a pressure signal corresponding to this change. Furthermore, when the temperature of the sensor chip changes, the voltage across the bridge circuit, which functions as the temperature measuring element, changes, and the sensor chip outputs a temperature signal corresponding to this change. As described above, in a pressure-temperature sensor like the one in Patent Document 1, pressure and temperature can be measured by a sensor chip that integrates both a pressure measuring element and a temperature measuring element. Therefore, miniaturization is possible. However, because two types of measurements are measured by a single sensor chip, the structure of a pressure-temperature sensor like the one in Patent Document 1 is limited. Furthermore, changes in the pressure of the transmitting element affect the temperature measuring element. Similarly, changes in the temperature of the transmitting element affect the pressure measuring element. Due to these factors, a pressure-temperature sensor like the one in Patent Document 1 could not accurately measure values for each individual element. Therefore, pressure-temperature sensors like the one described in Patent Document 1 have difficulty compensating for the influence of temperature on pressure measurement according to the temperature signal. As a result, the measured pressure and temperature values were inaccurate. However, it is possible to obtain accurate pressure and temperature values by pre-calibrating the relationship between pressure and temperature. However, sensor chips are manufactured using semiconductor processes, resulting in significant variations between production lots. Therefore, each sensor chip requires calibration for pressure and temperature, which is a very time-consuming process. Another example of a pressure-temperature sensor, shown in Patent Document 2, has a separate pressure measuring element and temperature measuring element. Specifically, the pressure measuring element is arranged in a housing space filled with a transmission material. The temperature measuring element is arranged protruding from the center of the diaphragm toward the fluid being measured. The temperature measuring element is constructed by fixing a thermistor, which is placed in a cap-shaped housing, with a resin that has high thermal conductivity filling it. Japanese Patent Publication No. 2009-121871 (pages 6-8, Figure 2)Japanese Patent Publication No. 2013-2885 (pag