WO2012071693A1

WO2012071693A1 - Pressure and temperature measuring device

Info

Publication number: WO2012071693A1
Application number: PCT/CN2010/079217
Authority: WO
Inventors: 吴茂庭
Original assignee: Wu Maoting
Priority date: 2010-11-29
Filing date: 2010-11-29
Publication date: 2012-06-07

Abstract

A pressure and temperature measuring device, comprises a case (10), a pressure sensor (20) and a circuit board (30) which are housed in the case (10). The pressure sensor (20) is connected with the case (10) to form a sealed housing cavity. An object to be measured flows into the housing cavity through an inlet hole (11) on the case (10). The pressure sensor (20) senses the pressure signals of the object to be measured in the housing cavity, and the circuit board (30) transforms the pressure signals into electric signals and outputs them. A temperature sensing element is disposed on the circuit board (30). The temperature sensing element senses the temperature signals of the object to be measured, and the circuit board (30) transforms the temperature signals into the electric signals and outputs them. The pressure and temperature measuring device has a simple structure, is convenient to install, and further improves its stability and measurement precision.

Description

Pressure temperature measuring device

Technical field

The invention relates to the field of measurement, and in particular to a pressure temperature measuring device.

Background technique

Pressure sensors are used to sense pressure and convert them into usable output signals. They are widely used in various industrial automation environments such as water conservancy and hydropower, railway transportation, intelligent buildings, production automation, aerospace, military, petrochemical, oil wells, and electric power. , ships, machine tools, pipelines and many other industries.

An existing engine oil pressure sensor is shown in FIG. The engine oil pressure sensor comprises a hollow housing 1 having a threaded joint 2 at one end and a terminal 3 at the other end. The middle portion of the threaded joint 2 is formed with a through hole 21 which communicates with the inside of the casing. The inside of the casing 1 is further provided with an elastic isolating diaphragm 4 and a circuit board 5, which are covered together and form a sealed cavity 6 therebetween, and the inside of the casing 1 is divided into two mutually disconnected spaces. The cavity 6 is filled with a pressure transmitting medium; the circuit board 5 is provided with a pressure sensing chip 51 on one side of the cavity 6, and a data acquisition chip on the other side, and is connected to the terminal 3 by means of a wire 52.

The engine oil pressure sensor described above is subjected to the pressure of the oil in the oil transfer chamber 41 through the elastic isolating diaphragm 4, and is transmitted to the pressure sensing chip 52. Although the elastic isolating diaphragm 4 can play a certain isolation function, the pressure sensing and re-transmission to the pressure sensing chip 52 greatly affect the measurement accuracy of the engine oil pressure sensor. Moreover, the molding process of the above-described housing 1 is complicated, the number of steps is large, and the manufacturing cost is large.

Summary of the invention

The main object of the present invention is to provide a pressure and temperature measuring device, which aims to reduce the production and processing difficulty of the pressure temperature sensor, simplify the manufacturing process, reduce the cost, and improve the productivity; and also improve the stability and measurement accuracy of the pressure and temperature measuring device.

The invention provides a pressure and temperature measuring device, comprising a housing and a pressure sensor and a circuit board housed in the housing, the pressure sensor being connected with the housing and forming a sealed receiving cavity for the object to be tested The inlet hole in the housing enters the receiving cavity; the pressure sensor senses a pressure signal of the object to be tested in the receiving cavity, and the pressure signal is converted into an electrical signal output by the circuit board.

Preferably, the circuit board is further provided with a temperature sensing component, and the temperature sensing component senses a temperature signal of the object to be tested in the receiving cavity, and the temperature signal is converted into an electrical signal output by the circuit board.

Preferably, the pressure sensor comprises a sensing portion and a strain gauge disposed on the sensing portion, the strain gauge is electrically connected to the circuit board, and the sensing portion is fixedly connected to the housing.

Preferably, at least two recesses are provided on the sensing portion for mounting the pressure sensor and the housing.

Preferably, the pressure temperature measuring device further includes a core shell, the core shell is integrally formed with the casing, the sensing portion is fixedly connected with the core shell, and the sealed receiving cavity is formed, the core body A through hole corresponding to the housing is disposed on the shell, and the object to be tested is in contact with the sensing portion by the through hole of the housing and the through hole of the core shell.

Preferably, the sidewall surface of the core shell is tooth-shaped, and provides a radial suction force between the core shell and the shell when the core shell is integrally formed with the shell.

Preferably, the side wall of the core shell is further provided with a ring groove, which provides a lateral suction force between the core shell and the shell when the core shell is integrally formed with the shell.

Preferably, the inner wall of the casing is provided with a holding groove, and both sides of the circuit board are locked in the holding groove; and one end of the housing receiving circuit board is provided with a wire hole for the output line of the circuit board to pass through The housing is connected to the outside world.

Preferably, one end of the housing receiving pressure sensor is provided with a mounting portion for connecting the object receiving device, and the housing is fixedly connected to the object receiving device through the mounting portion, and the inlet hole penetrates the mounting portion.

The invention is fixedly connected with the housing through the pressure sensor and forms a receiving cavity, so that the pressure sensor can better sense the pressure signal of the object to be tested in the receiving cavity, and the circuit board disposed separately from the pressure sensor will The pressure signal is transmitted out. The pressure temperature measuring device has the advantages of simple structure, convenient and quick installation, and further improves the stability and measurement precision of the pressure temperature measuring device.

DRAWINGS

1 is a schematic structural view of a pressure sensor in the prior art;

2 is an exploded perspective view of an embodiment of a pressure temperature measuring device of the present invention;

3 is an exploded perspective view of the housing in an embodiment of the pressure temperature measuring device of the present invention;

4 is another exploded perspective view of the housing in an embodiment of the pressure temperature measuring device of the present invention;

Figure 5 is an exploded perspective view showing a core body and a pressure sensor in another embodiment of the pressure temperature measuring device of the present invention;

6A is a schematic view showing a combined structure of a core shell and a pressure sensor in another embodiment of the pressure temperature measuring device of the present invention;

Figure 6B is a schematic cross-sectional view taken along line A-A of Figure 6A.

The implementation, functional features, and advantages of the present invention will be further described in conjunction with the embodiments.

detailed description

It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in FIGS. 2 and 3, the pressure temperature measuring device of the present invention includes a housing 10 and a pressure sensor 20 and a circuit board 30 housed in the housing 10. The pressure sensor 20 is coupled to the housing 10 and forms a closed receiving cavity for the object to be tested to enter the receiving cavity from the inlet opening 11 in the housing 10. The pressure sensor 20 will sense the pressure signal of the object to be tested in the receiving cavity, and the pressure signal is converted into an electrical signal by the circuit board 30.

The circuit board 30 is further provided with a temperature sensing component, and the temperature sensing component can sense the temperature signal of the object to be tested in the receiving cavity, and the temperature signal is converted into an electrical signal output by the circuit board.

The pressure sensor 20 includes a sensing portion 21 and a strain gauge 22 disposed on the sensing portion 21. The sensing portion 21 is fixedly coupled to the housing 10. The strain gauge 22 is electrically connected to the circuit board 30. The sensing portion 21 transmits the pressure of the object to be tested in the receiving chamber to the strain gauge 22, and the strain gauge 22 converts the pressure into a pressure signal and outputs it through the circuit board. The circuit board 30 may also include a signal processing circuit that processes and outputs the pressure signal. The sensing portion 21 includes a base portion and a connecting portion extending from the edge of the vertical base. The strain gauge 22 is disposed on the base portion, and the connecting portion forms a sealed connection with the housing 10 and forms a sealed receiving cavity. The sealing connection may be a threaded connection, a snap connection or a glue bond, etc., for better sealing, this embodiment is preferably a threaded connection.

At least two recesses 211 are further provided on the sensing portion 21 for mounting the pressure sensor 20 and the housing 10. For example, the pressure sensor 20 can be fixedly coupled to the housing 10 by a mounting tool having two latching legs, holding the latching legs in the recess 211, and rotating the mounting tool.

One end of the housing 10 housing the pressure sensor 20 is provided with a mounting portion 12 for connecting the object receiving device (not shown). The housing 10 is fixedly coupled to the object-receiving device through the mounting portion 12, and the inlet hole 11 extends through the mounting portion 12. The fixed connection can be a threaded connection, a snap connection or a glue bond. The present embodiment is preferably a threaded connection, that is, the outer wall of the mounting portion 12 is provided with a threaded structure, so that the housing 10 is stably connected to the object receiving device through the mounting portion 12.

Referring to FIG. 4 , the inner wall of the casing 10 is provided with a holding groove 13 , and both sides of the circuit board 30 are clamped in the holding groove 13 . One end of the housing 10 housing the circuit board 30 is provided with a wire hole 14 through which the output line of the circuit board 30 is connected to the outside through the housing 10.

The pressure temperature measuring device of the embodiment is fixedly connected to the housing 10 through the pressure sensor 20, and forms a receiving cavity, so that the pressure sensor 20 can better sense the pressure signal of the object to be tested in the receiving cavity, and the pressure and pressure The circuit board 30, which is separately provided by the inductor 20, transmits the pressure signal. Therefore, the pressure temperature measuring device has a simple structure, convenient and quick installation, and further improves the stability and measurement accuracy of the pressure temperature measuring device.

The manufacturing process of the above pressure temperature measuring device may include the following steps:

(1) respectively forming the pressure sensor 20 and the housing 10 in accordance with their predetermined shapes;

(2) The formed pressure sensor 20 is placed in the mounting position of the housing 10, and then the pressure sensor 20 is screwed and fixed in the housing 10 by the installation tool;

(3) holding the circuit board 30 in the holding slot 13 of the housing 10;

(4) The two parts of the housing 10 are then covered by a screw connection.

In the manufacturing process of the above pressure temperature measuring device, the casing 10 is preferably one-shot injection molding, which is characterized in that the molding cycle is short, and the plastic parts with complicated shapes, accurate dimensions, and metal or non-metal inserts can be formed at one time. In the prior art, the housing 10 must be completed by multiple moldings. Therefore, the manufacturing process of the pressure temperature measuring device is simpler than the prior art, and the production process is high.

5, 6A, and 6B, the pressure temperature measuring device further includes a core case 40. The core case 40 is integrally formed with the housing 10, and the sensing portion 21 of the pressure sensor 20 is fixedly coupled to the core case 40 to form the receiving cavity. The fixed connection may be a threaded connection, a snap connection or a glue bond or the like. This embodiment is preferably a threaded connection. The through hole 41 corresponding to the inlet hole 211 is further disposed on the core shell 40, and the object to be tested can enter the receiving cavity from the inlet hole 11 in the casing 10 and the through hole 41 in the core shell 40.

The outer side wall surface of the core shell 40 has a tooth-like shape, and provides a radial suction force between the core shell 40 and the casing 10 when the core shell 40 is integrally formed with the casing 10. The outer side wall ring of the core shell 40 is provided with a ring groove 42 for providing a lateral suction force between the core shell 40 and the casing 10 when the core shell 40 is integrally formed with the casing 10.

(1) The pressure sensor 20 and the core shell 40 are respectively formed in accordance with their predetermined shapes;

(2) placing the molded core shell 40 in a molding die of the casing 10, integrally formed with the casing 10;

(3) The formed pressure sensor 20 is placed in the assembled position of the core shell 40 in the molded casing 10, and then the pressure sensor 20 is screwed and fixed in the core shell 40 by the installation tool;

(4) holding the circuit board 30 in the holding slot 13 of the housing 10;

(5) The two parts of the housing 10 are then covered by a screw connection.

In this embodiment, the pressure sensor 20 and the core shell 40 are respectively molded, and then the core shell 40 and the shell 10 are integrally formed. Finally, the pressure sensor 20 is mounted on the core shell 40, so that the pressure sensor 20 is The core shell 40 can be stably mounted on the core shell 40, and the outer side of the core shell 40 is provided with a tooth groove and a groove structure, which further ensures the stable connection between the pressure sensor 20 and the casing 10, and improves the pressure temperature measuring device. measurement accuracy.

The above description is only a preferred embodiment of the present invention, and thus does not limit the scope of the invention, and the equivalent structural transformations made by the description of the present invention and the contents of the drawings are directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Claims

A pressure and temperature measuring device, comprising: a housing and a pressure sensor and a circuit board housed in the housing, the pressure sensor being connected with the housing and forming a sealed receiving cavity for the object to be tested The inlet hole in the housing enters the receiving cavity; the pressure sensor senses a pressure signal of the object to be tested in the receiving cavity, and the pressure signal is converted into an electrical signal output by the circuit board.
The pressure temperature measuring device according to claim 1, wherein the circuit board is further provided with a temperature sensing component, and the temperature sensing component senses a temperature signal of the object to be tested in the receiving cavity, and the circuit board The temperature signal is converted to an electrical signal output.
The pressure temperature measuring device according to claim 1, wherein the pressure sensor comprises a sensing portion and a strain gauge disposed on the sensing portion, the strain gauge is electrically connected to the circuit board, The sensing portion is fixedly connected to the housing.
The pressure-temperature measuring device according to claim 3, wherein at least two recesses are provided in the sensing portion for mounting the pressure sensor and the housing.
The pressure-temperature measuring device according to any one of claims 1 to 4, further comprising a core shell integrally formed with the casing, the sensing portion being fixedly connected to the core shell And forming a closed receiving cavity, wherein the core shell is provided with a through hole corresponding to the casing, and the object to be tested is passed through the through hole of the casing and the through hole of the core shell Sensing contact.
The pressure temperature measuring device according to claim 5, wherein the side wall surface of the core shell is in the form of a tooth, and the core shell and the shell are provided when the core shell is integrally formed with the shell Radial suction force between the bodies.
The pressure and temperature measuring device according to claim 5, wherein the side wall of the core shell is further provided with a ring groove, and the core shell is provided when the core shell and the shell are integrally formed. The lateral suction force between the housings.
The pressure temperature measuring device according to claim 1, wherein the inner wall of the casing is provided with a holding groove, and both sides of the circuit board are held in the holding groove; and the housing receives the circuit board One end of the circuit is provided with a wire hole for the output line of the circuit board to be connected to the outside through the housing.
The pressure and temperature measuring device according to claim 1, wherein one end of the housing receiving pressure sensor is provided with a mounting portion for connecting the object receiving device, and the housing is received by the mounting portion and the object to be tested. The device is fixedly connected, and the inlet hole extends through the mounting portion.