Oil charge pressure sensor

Abstract

The utility model relates to the technical field of pressure sensors, and discloses an oil-filled pressure sensor, which comprises a sensor main body, a chip slot is arranged at the end part of the main body, an annular flange is formed outside the chip slot of the main body, a pressure sensitive sensing chip is arranged in the chip slot, a signal pin of the chip is led out from the main body, and the pressure sensitive sensing chip is arranged in the chip slot. The annular flange is provided with an isolation diaphragm, a pressing ring is arranged outside the isolation diaphragm and seals the chip groove, the chip groove is filled with oil media, the pressing ring is connected with the outer ring and the inner ring of the annular flange of the main body in a welded mode, and therefore the isolation diaphragm is connected with the main body in a sealed mode. According to the utility model, the isolation diaphragms between the inner ring and the outer ring of the pressing ring on the flange of the chip groove are respectively welded and sealed, so that gapless isolation diaphragm connection is realized, and measurement errors caused by the fact that small particles are clamped into gaps are avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of pressure sensors, in particular to an oil-filled pressure sensor. Background Art

[0002] See attached Figure 2 One of the most widely used core components of pressure sensors is the oil-filled sensor module, which includes a main body, a pressure-sensitive sensor chip, an isolation diaphragm and a pressure ring. The isolation diaphragm is welded together by welding (laser welding or inert gas welding, argon arc welding, etc.) to form a sealed connection.

[0003] The main body usually contains a glass sintered sealing structure to achieve electrical connection from the sensing element to the lead wire. This structure can transmit the pressure of the medium to be measured to the pressure sensitive chip through a very thin isolation film and oil-filled medium to achieve pressure measurement.

[0004] See attached Figure 3 ,Since the isolation diaphragm is very thin, the welding depth needs to be less than the radial thickness of the pressure ring to avoid burning through the isolation diaphragm. This leaves a small gap between the pressure ring and the isolation diaphragm. This is usually not a problem for air or liquid pressure measurement. However, for media containing solid particles such as mud, food, etc., tiny particles may get stuck in the gap. With long-term and repeated use of the product, these particles will accumulate in the gap. When enough material is stuck in this area, the isolation diaphragm will have a deformation displacement, which will generate pressure on the oil-filled medium behind the diaphragm and transmit it to the pressure sensor chip, resulting in measurement errors. The tiny particles in the gap can increase or decrease during use, making the measurement error an uncertainty. This phenomenon is particularly prominent in oil well pressure measurement. The measured medium generally contains mud and sand, and the application requires extremely high pressure measurement accuracy. Utility Model Content

[0005] The purpose of the utility model is to solve the above-mentioned problem and provide an oil-filled pressure sensor, which realizes a gapless isolation diaphragm connection by welding and sealing the isolation diaphragm between the inner and outer rings of the pressure ring on the chip slot flange, thereby avoiding measurement errors caused by tiny particles getting stuck in the gap.

[0006] The technical solution adopted by the utility model is:

[0007] An oil-filled pressure sensor, characterized in that it includes a sensor body, a chip slot is provided at the end of the body, an annular flange is formed on the body outside the chip slot, a pressure-sensitive sensor chip is installed in the chip slot, and the signal pins of the chip are led out from the body, an isolation diaphragm is provided on the annular flange, a pressure ring is provided outside the isolation diaphragm, the isolation diaphragm seals the chip slot, the chip slot is filled with oil medium, and the pressure ring is welded to the outer and inner ring positions of the annular flange of the body to seal the isolation diaphragm and the body.

[0008] Furthermore, the welding connection is accomplished by laser welding, inert gas welding, argon arc welding, or any other reasonable welding process.

[0009] Furthermore, the main body is provided with a pin hole, the signal of the chip is led out from the pin hole, and a glass layer is sintered in the pin hole.

[0010] The beneficial effects of the utility model are:

[0011] (1) By welding and sealing the isolation diaphragms between the inner and outer rings of the pressure ring on the chip slot flange, a gap-free isolation diaphragm connection is achieved to avoid measurement errors caused by tiny particles getting stuck in the gap;

[0012] (2) The original structure and size of the sensor shall not be changed. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Attached Figure 1 It is a cross-sectional structural schematic diagram of the utility model;

[0014] Attached Figure 2 It is a cross-sectional schematic diagram of a pressure sensor in the prior art;

[0015] Attached Figure 3 Yes Figure 2 A partial enlarged view of A in FIG.

[0016] The reference numerals in the accompanying drawings are:

[0017] 1. Main body; 2. Chip slot;

[0018] 3. Annular flange; 4. Chip;

[0019] 5. Pin hole; 6. Signal pin;

[0020] 7. Glass layer; 8. Isolation membrane;

[0021] 9. Pressing ring; 10. First welding ring;

[0022] 11. Second welding ring. DETAILED DESCRIPTION

[0023] The specific implementation of the oil-filled pressure sensor of the utility model is described in detail below with reference to the accompanying drawings.

[0024] See attached Figure 1 The oil-filled pressure sensor includes a sensor body 1, a chip slot 2 is provided at the end of the body 1, an annular flange 3 is formed outside the chip slot 2, a pressure sensitive sensor chip 4 is installed in the chip slot 2, a pin hole 5 is provided on the body 1, a signal pin 6 of the chip 4 is led out from the pin hole 5, and a glass layer 7 is sintered in the pin hole 5.

[0025] An isolation diaphragm 8 is provided on the annular flange 3, and a pressure ring 9 is provided outside the isolation diaphragm 8. The isolation diaphragm 8 seals the chip slot 2, and the chip slot 2 is filled with oil medium. The pressure ring 9 is welded to the outer ring and inner ring of the annular flange 3 of the main body 1, so that the isolation diaphragm 8 and the main body 1 are sealed.

[0026] The operation process is as follows: fix the isolation diaphragm 8 and the pressure ring 9 on the annular flange 3, fuse the outer ring of the pressure ring 9, the isolation diaphragm 8 and the outer ring of the annular flange 3 together by laser welding or argon arc welding to form a first welding ring 10, and then fuse the inner ring of the pressure ring 9, the isolation diaphragm 8 and the inner ring of the annular flange 3 together to form a second welding ring 11. By properly adjusting the welding energy, the inner and outer corners of the pressure ring 9 and the diaphragm and main body material connected thereto are all melted, and the isolation diaphragm 8 is prevented from being burned through, thereby realizing a gapless isolation diaphragm 8 connection and avoiding measurement errors caused by tiny particles getting stuck in the gap.

[0027] The above are only preferred implementations of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An oil-filled pressure sensor, characterized in that: It includes a sensor body, a chip groove is provided at the end of the body, an annular flange is formed on the body outside the chip groove, a pressure sensitive sensor chip is installed in the chip groove, the signal pins of the chip are led out from the body, an isolation diaphragm is provided on the annular flange, a pressure ring is provided outside the isolation diaphragm, the isolation diaphragm seals the chip groove, the chip groove is filled with oil medium, the pressure ring is welded to the outer and inner ring positions of the annular flange of the body, so that the isolation diaphragm and the body are sealed and connected.

2. The oil-filled pressure sensor according to claim 1, characterized in that: The welding connection method is completed by a welding process selected from the group consisting of laser welding, inert gas welding and argon arc welding.

3. The oil-filled pressure sensor according to claim 1 or 2, characterized in that: The main body is provided with a pin hole, the signal pins of the chip are led out from the pin hole, and a glass layer is sintered in the pin hole.

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