CN106678403B - A kind of proportional pressure-reducing valve - Google Patents

Abstract

The invention discloses a proportional pressure reducing valve, comprising: a low-pressure chamber plug cover, a casing, an air inlet joint, a high-pressure chamber plug cover, a high-pressure chamber piston, a sealing ring, an air outlet joint and a low-pressure chamber piston; wherein, the low-pressure chamber The blocking cover is connected with one end of the casing, and the high-pressure cavity blocking cover is connected with the other end of the casing; the low-pressure cavity blocking cover, the casing and the high-pressure cavity blocking cover form an inner cavity; the low-pressure cavity piston is arranged on the In the low pressure chamber, the outer side wall of the first end of the low pressure chamber piston can be crimped with the inner side wall of the sealing ring, and the low pressure chamber piston can move up and down along the axis of the cavity; the high pressure chamber piston is arranged in the high pressure chamber, and the high pressure chamber piston The second end of the piston is in contact with the first end of the low-pressure chamber piston, and the high-pressure chamber piston can move up and down along the axis of the cavity. The invention can well solve the problems of short valve life and air leakage, is suitable for long-term decompression and inflation in shock wave wind tunnels, has simple structure, is easy to process and has low manufacturing cost.

Description

A proportional pressure reducing valve

technical field

The invention relates to the field of fluid valve control, in particular to a proportional pressure reducing valve.

Background technique

Proportional pressure reducing valve is a device for controlling fluid. It relies on the balanced movement of the internal piston to open or close the vent, so that the outlet pressure is equal to 1/2 of the inlet pressure; the valve has a compact structure, low maintenance cost and simple structure, and is suitable for wind turbines. Pressure control occasions where the hole ruptures membrane, and areas where proportional decompression is required.

At present, the proportional control of the film breaking pressure in the shock tunnel mainly uses the opening and closing of the shut-off valve, observes the actual pressure value, and frequently controls the on-off of the airflow to achieve the required target pressure value. In general, a 1/2 proportional valve is required for a shock tunnel to achieve rapid rupture of the diaphragm and to achieve pressure control in the wind tunnel. For example, CAAA's FD-20 shock/gun wind tunnel uses manual pressure regulation to break the membrane, the FD-22 gun wind tunnel uses a solenoid valve to manually control the film rupture, and the FD-22a gun wind tunnel uses a 1/2 proportional pressure reducing valve to control.

Using a shock tunnel with compressed air or nitrogen as the medium, the pressure adjustment process varies from a few minutes to an hour depending on the inflation pressure. For high-pressure operation, the time is long, which requires the personnel to concentrate and control the pressure accurately, otherwise it will affect the quality of the ruptured membrane; long-term operation, the operator is labor-intensive. Low, basically half a year to replace. In order to reduce the labor intensity and improve the control precision, a proportional pressure reducing valve is designed and applied to the FD-22a gun wind tunnel.

Although the FD-22 wind tunnel has used a 1/2 proportional pressure reducing valve, which improves the pressure control accuracy and reduces the labor intensity of operators; however, during use, it is found that due to the use of rubber sealing materials, small sealing ports are used, and the valve Under the condition of frequent opening and closing, the valve port is prone to indentation. Under relatively high pressure, especially over 35MPa, the air leakage is very obvious and cannot be used. At present, only the 1/2 proportional pressure reducing valve is used under the pressure of 30MPa. If the pressure exceeds 30MPa, the pressure control still depends on the operator to control the globe valve.

According to the use experience, using tetrafluoroethylene sealing material, after using for a period of time, it is difficult to restore the original shape after the sealing port has indentation, and air leakage occurs. Using soft rubber material, after a period of use, the valve port will be worn out and air leakage will occur. At present, the problem can only be solved by replacing the seals more frequently.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is: compared with the prior art, a proportional pressure reducing valve is provided, which can well solve the problems of short valve life and air leakage, is suitable for long-term decompression and inflation in a shock tunnel, and has a simple structure. Easy to process and low manufacturing cost.

The object of the present invention is achieved through the following technical solutions: a proportional pressure reducing valve, comprising: a low-pressure chamber plug, a casing, an air inlet joint, a high-pressure chamber plug, a high-pressure chamber piston, a sealing ring, an air outlet connector and a low-pressure chamber piston; Wherein, the low pressure chamber cover is connected to one end of the casing, and the high pressure chamber cover is connected to the other end of the casing; the low pressure chamber cover, the casing and the high pressure The cavity blocking cover forms an internal cavity, wherein the cavity includes a low-pressure cavity and a high-pressure cavity, and the low-pressure cavity and the high-pressure cavity communicate with each other; the sealing ring is arranged at the communication position of the low-pressure cavity and the high-pressure cavity, wherein the outer surface of the sealing ring crimped with the inner wall of the casing; the low pressure chamber piston is arranged in the low pressure chamber, the outer side wall of the first end of the low pressure chamber piston can be crimped with the inner side wall of the sealing ring, and the low pressure chamber piston can Move up and down along the axis of the cavity; the high-pressure chamber piston is arranged in the high-pressure chamber, the second end of the high-pressure chamber piston is in contact with the first end of the low-pressure chamber piston, and the high-pressure chamber piston can move along the The axis of the cavity moves up and down; one side of the casing is provided with an air inlet joint, wherein the air inlet joint is connected with the upper part of the high pressure cavity through the first passage, and the air inlet joint is connected with the lower end of the high pressure cavity through the second passage. The other side of the casing is provided with an air outlet joint, wherein the air outlet joint is connected with the lower part of the low pressure cavity through the third passage, and the air outlet joint is connected with the upper end of the low pressure cavity through the fourth passage.

The above proportional pressure reducing valve further includes: a high-pressure chamber sealing film, wherein the high-pressure chamber sealing film is arranged in the high-pressure chamber and is located at the lower part of the high-pressure chamber piston.

The above proportional pressure reducing valve further includes: a low pressure chamber sealing film, wherein the low pressure chamber sealing film is arranged in the low pressure chamber and is located on the upper part of the low pressure chamber piston.

The above proportional pressure reducing valve further includes: a first air release joint and a second air release joint; wherein, the first air release joint is arranged on one side of the casing, and the first air release joint passes through the casing. The fifth channel opened by the body is connected with the first end of the low pressure cavity; the second air release joint is arranged on the other side of the shell, and the second air release joint is connected to the sixth channel opened by the shell. The second end of the high pressure chamber is connected.

The proportional pressure reducing valve further includes: a locking stud; wherein, the diameter of the bottom end of the low-pressure chamber is smaller than the diameter of the upper end of the high-pressure chamber; the locking stud is arranged in the high-pressure chamber, and is connected with the casing The inner wall of the body is threadedly connected; the diameter of the sealing ring is equal to the diameter of the upper end of the high pressure chamber, one end of the sealing ring is crimped with the bottom end of the low pressure chamber, and the other end of the sealing ring is connected to the locking stud The locking stud is provided with a through cavity, and the second end of the high pressure chamber piston passes through the through cavity and contacts with the first end of the low pressure cavity piston.

In the above proportional pressure reducing valve, the low-pressure chamber cover is connected to one end of the casing by a screw, and the high-pressure chamber plug is connected to the other end of the casing by a screw.

In the above proportional pressure reducing valve, the cross-sectional shape of the opening of the sealing ring along the axis is a trapezoid, and correspondingly, the side wall of the first end of the low pressure chamber piston matches the opening of the sealing ring.

In the above proportional pressure reducing valve, the cross-sectional shape of the low-pressure cavity along its axis is a T-shaped cavity, and the shape of the low-pressure cavity piston matches the shape of the low-pressure cavity; the cross-sectional shape of the high-pressure cavity along its axis is: Inverted T-shaped cavity, the shape of the high-pressure cavity piston matches the shape of the high-pressure cavity.

In the above proportional pressure reducing valve, the sealing ring is a polytetrafluoroethylene sealing ring.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The present invention adopts the overall structure of the proportional pressure reducing valve to solve the problems of short service life and air leakage of the existing valve, and is suitable for long-term pressure reduction and inflation in a shock tunnel, with simple structure, easy processing and low manufacturing cost;

(2) The present invention adopts the low-pressure cavity sealing film to make the sealing effect good;

(3) the present invention adopts the high-pressure chamber sealing film to make the sealing effect good;

(4) The material of the sealing ring used in the present invention is polytetrafluoroethylene material, and the service life is long;

(5) The structure of the present invention is simple, easy to manufacture, and low in cost.

Description of drawings

Fig. 1 is the structural representation of the proportional pressure reducing valve of the present invention;

Fig. 2 is the structural representation of the low-pressure chamber plugging cover of the present invention;

3 is a schematic structural diagram of a high-pressure chamber plugging cover of the present invention;

Figure 4 (a) is a top view of the housing of the present invention;

Figure 4(b) is a bottom view of the housing of the present invention;

Fig. 5 is the structural representation of the sealing ring of the present invention;

Figure 6(a) is a left side view of the locking stud of the present invention;

Figure 6(b) is a sectional view of the locking stud of the present invention along the axis;

Fig. 7 is the structural representation of the high-pressure chamber piston of the present invention;

FIG. 8 is a schematic structural diagram of the low pressure chamber piston of the present invention.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in further detail:

FIG. 1 is a schematic structural diagram of a proportional pressure reducing valve of the present invention. As shown in Figure 1, the proportional pressure reducing valve includes: a low pressure chamber cover 1, a housing 2, an air inlet connector 4, a high pressure chamber cover 5, a high pressure chamber piston 7, a sealing ring 9, an air outlet connector 11 and a low pressure chamber piston 12; of which,

The low-pressure chamber blocking cover 1 is connected to one end of the casing 2 , and the high-pressure chamber blocking cover 5 is connected to the other end of the casing 2 . In specific implementation, the material of the low-pressure chamber plug 1 is 304 stainless steel, the material of the high-pressure chamber plug 5 is 304 stainless steel, and the material of the shell 2 is 304 stainless steel. The axis and the axis of the high-pressure chamber blocking cover 5 are the same axis.

The low pressure chamber cover 1 , the housing 2 and the high pressure chamber cover 5 form an internal cavity, wherein the cavity includes a low pressure chamber 151 and a high pressure chamber 152 , and the low pressure chamber 151 and the high pressure chamber 152 communicate with each other. Specifically, the low-pressure chamber cover 1 seals the upper end of the casing 2, the high-pressure chamber cover 5 seals the lower end of the casing 2, and an internal 's cavity. The cavity is divided into two parts, a low pressure cavity 151 and a high pressure cavity 152 .

The sealing ring 9 is arranged at the communication position between the low pressure chamber 151 and the high pressure chamber 152 , wherein the outer surface of the sealing ring 9 is in crimp contact with the inner wall of the housing 2 . In specific implementation, the sealing ring 9 is a polytetrafluoroethylene sealing ring.

The low pressure chamber piston 12 is arranged in the low pressure chamber 151 , the outer side wall of the first end 121 of the low pressure chamber piston 12 can be crimped with the inner side wall of the sealing ring 9 , and the low pressure chamber piston 12 can move up and down along the axis of the cavity. Specifically, the cross-sectional shape of the low-pressure chamber 151 along its axis is a T-shaped chamber, and the shape of the low-pressure chamber piston 12 matches the shape of the low-pressure chamber 151 . The axis of the cavity coincides with the axis of the housing 2 .

The high pressure chamber piston 7 is arranged in the high pressure chamber 152 , the second end 71 of the high pressure chamber piston 7 is in contact with the first end 121 of the low pressure chamber piston 12 , and the high pressure chamber piston 7 can move up and down along the axis of the cavity. Specifically, the cross-sectional shape of the high-pressure chamber 152 along its axis is an inverted T-shaped chamber, and the shape of the high-pressure chamber piston 7 matches the shape of the high-pressure chamber 152 . The axis of the cavity coincides with the axis of the housing 2 .

One side of the housing 2 is provided with an air inlet joint 4 , wherein the air inlet joint 4 is connected with the upper part of the high pressure chamber 152 through the first passage 41 , and the air inlet joint 4 is connected with the lower end of the high pressure chamber 152 through the second passage 42 . Specifically, an air inlet joint 4 is provided on the left side of the casing 2 , the first passage 41 and the second passage 42 have the same section of pipe, the first passage 41 is opened inside the casing 2 , and the first passage 41 is connected to the high pressure The upper part of the cavity 152 is connected, and further, the first channel 41 is connected with the upper part A of the high pressure cavity 152 in FIG. 1 . A second channel 42 is jointly opened in the interior of the casing 2 and the high-pressure chamber cover 5 , and the second channel 42 is connected with the lowermost end of the high-pressure chamber 152 .

The other side of the housing 2 is provided with an outlet joint 11 , wherein the outlet joint 11 is connected to the lower part of the low pressure chamber 151 through the third passage 111 , and the outlet joint 11 is connected to the upper end of the low pressure chamber 151 through the fourth passage 112 . Specifically, an air outlet joint 11 is provided on the right side of the casing 2 , the third passage 111 and the fourth passage 112 have the same section of pipeline, the third passage 111 is opened inside the casing 2 , and the third passage 111 is connected to the low pressure chamber. The lower part of 151 is connected, and further, the third channel 111 is connected with the upper part B of the low pressure chamber 151 in FIG. 1 . A fourth channel 112 is jointly opened in the housing 2 and the inside of the low-pressure chamber blocking cover 1 , and the fourth channel 112 is connected to the uppermost end of the low-pressure chamber 151 .

The working principle is as follows: the high-pressure air source is connected by the intake joint 4, enters the high-pressure chamber 152, the high-pressure chamber piston 7 generates a moving distance, and makes the high-pressure chamber piston 7 resist the low-pressure chamber piston 12 to move upward, so that the low-pressure chamber piston 12 is disengaged The sealing ring 9 causes a gap between the low-pressure chamber piston 12 and the sealing ring 9, and the high-pressure gas passes through the gap to the outlet joint 11 and the low-pressure chamber of the outlet. The force on the low-pressure chamber piston 12 gradually increases. When the gas pressure reaches 1/2 of the inlet pressure, the two forces are balanced, and the gap between the sealing ring and the low-pressure chamber piston 12 adapts to the flow requirements and remains in a proper position. When the outlet pressure exceeds 1/2 of the inlet pressure, the low-pressure chamber piston 12 gradually moves in the opposite direction, so that the gap between the sealing ring and the low-pressure chamber piston 12 gradually becomes smaller, and the outlet pressure is maintained near 1/2 of the inlet pressure, The pressure control accuracy is basically 1%.

This embodiment adopts the overall structure of the proportional pressure reducing valve to solve the problems of short service life and air leakage of the existing valve, and is suitable for long-term decompression and inflation in a shock tunnel, with a simple structure, easy processing and low manufacturing cost; and this embodiment The structure is simple, easy to process and manufacture, and the cost is low.

In the above embodiment, as shown in FIG. 1 , the proportional pressure reducing valve further includes: a high-pressure chamber sealing film 6 , wherein the high-pressure chamber sealing film 6 is arranged in the high-pressure chamber 152 and is located at the lower part of the high-pressure chamber piston 7 . Specifically, the high-pressure chamber sealing membrane 6 is made of high-grade fluororubber material, and is designed to be cast in a mold. The high-pressure chamber sealing film 6 is arranged at the connection position between the casing 2 and the high-pressure chamber blocking cover 5, the high-pressure chamber sealing film 6 is located in the high-pressure chamber 152, and is located at the lower part of the high-pressure chamber piston 7, and the upper surface of the high-pressure chamber sealing film 6 is in close contact with The lower end of the high pressure chamber piston 7. During the process of inflating the high-pressure chamber 152 through the second passage 42 through the air inlet joint 4, the high-pressure chamber sealing film 6 is deformed, so that the high-pressure chamber sealing film 6 causes the high-pressure chamber piston 7 to move upward. Further, relying on the high-pressure chamber sealing film 6 The deformation itself can realize the movement of the high-pressure chamber piston 7 by 3 mm to 5 mm. The effect achieved by the high-pressure chamber sealing film 6 is that the high-pressure air is sealed in the chamber where the high-pressure chamber piston 7 is located, no gas leakage occurs, and the pressure received by the piston is kept accurate.

In the above embodiment, as shown in FIG. 1 , the proportional pressure reducing valve further includes: a low pressure chamber sealing film 13 , wherein the low pressure chamber sealing film 13 is arranged in the low pressure chamber 151 and located on the upper part of the low pressure chamber piston 12 . Specifically, the low-pressure cavity sealing film 13 is made of high-grade fluororubber material, and is designed to be cast in a mold. The low pressure chamber sealing film 13 is arranged at the connection position between the casing 2 and the low pressure chamber cover 1, the low pressure chamber sealing film 13 is located in the low pressure chamber 151, and is located on the upper part of the low pressure chamber piston 12, and the lower surface of the low pressure chamber sealing film 13 is close to The upper end of the low pressure chamber piston 12 . Depending on the deformation of the low-pressure chamber sealing film 13 itself, the movement of the low-pressure chamber piston 12 of 3 mm to 5 mm can be realized. The effect achieved by the low-pressure chamber sealing film 13 is that the high-pressure air is sealed in the chamber where the low-pressure chamber piston 12 is located, so that no gas leaks, and the pressure on the piston is kept accurate.

In the above-mentioned embodiment, as shown in FIG. 1 , the proportional pressure reducing valve further comprises: a first air release joint 3 and a second air release joint 10; wherein,

The first air release joint 3 is disposed on one side of the casing 2 , and the first air release joint 3 is connected to the first end 1511 of the low pressure chamber 151 through the fifth channel 31 opened in the casing 2 . Specifically, the first venting joint 3 is arranged on the left side of the housing 2, and the function of the first venting joint 3 is to keep the internal pressure of the first end 1511 connected to the atmosphere, and the pressure is one atmospheric pressure.

The second air vent 10 is disposed on the other side of the housing 2 , and the second air vent 10 is connected to the second end 1521 of the high pressure chamber 152 through the sixth channel 101 opened in the housing 2 . Specifically, the second air release joint 10 is disposed on the right side of the housing 2 , and the function of the second air release joint 10 is to keep the internal pressure of the second end 1521 connected to the atmosphere, and to keep the pressure at one atmospheric pressure.

In the above embodiment, as shown in FIG. 1 , the proportional pressure reducing valve further includes: a locking stud 8; wherein,

The diameter of the bottom end of the low pressure chamber 151 is smaller than the diameter of the upper end of the high pressure chamber 152 . Specifically, the axis of the low pressure chamber 151 and the axis of the high pressure chamber 152 are the same axis, and the diameter of the bottom end of the low pressure chamber 151 is smaller than the diameter of the upper end of the high pressure chamber 152, so that the connection position of the low pressure chamber 151 and the high pressure chamber 152 is convex.

The locking stud 8 is disposed in the high pressure chamber 152 and is threadedly connected with the inner wall of the housing 2 . Specifically, the inner wall of the casing 2 where the high pressure chamber 152 is opened is provided with an inner thread, and the locking stud 8 is threadedly connected to the inner wall of the casing 2 .

The diameter of the sealing ring 9 is equal to the diameter of the upper end of the high pressure chamber 152 . Specifically, since the diameter of the sealing ring 9 is equal to the diameter of the upper end of the high pressure chamber 152 , the diameter of the sealing ring 9 is larger than the diameter of the bottom end of the low pressure chamber 151 , and the sealing ring 9 can be arranged at the communication position between the low pressure chamber 151 and the high pressure chamber 152 , so that the upper end of the sealing ring 9 is tightly squeezed with the lower end of the low pressure chamber 151 , and the lower end of the sealing ring 9 is tightly squeezed with the upper end of the locking stud 8 .

As shown in FIG. 6( a ) and FIG. 6( b ), the locking stud 8 is provided with a through cavity, and the second end 71 of the high pressure chamber piston 7 passes through the through cavity and the first end 121 of the low pressure cavity piston 12 contact. Specifically, the axis of the through chamber coincides with the axis of the high-pressure chamber piston 7 . One end of the locking stud 8 is an inner hexagonal hole, which is convenient for locking during assembly, and the inside is a smooth round hole as a piston cavity.

In the above-mentioned embodiment, the low-pressure chamber blocking cover 1 is connected to one end of the casing 2 through the screw 14 . Specifically, as shown in FIG. 2 , the low-pressure chamber cover 1 has a plurality of through holes uniformly opened along its circumferential direction, and the upper end of the casing 2 is provided with a plurality of blind holes ( As shown in FIG. 4( a ), screws 14 pass through the through hole of the low pressure chamber cover 1 and the blind hole at the upper end of the casing 2 to connect the low pressure chamber cover 1 and the upper end of the casing 2 .

The high-pressure chamber blocking cover 5 is connected to the other end of the housing 2 through screws 14 . Specifically, as shown in FIG. 3 , the high-pressure chamber cover 5 is provided with a number of through holes evenly along its circumferential direction, and the lower end of the casing 2 is provided with a number of blind holes corresponding to the through holes of the high-pressure chamber cover 5 ( As shown in FIG. 4( b ), the screws 14 pass through the through hole of the high pressure chamber cover 5 and the blind hole at the lower end of the casing 2 to connect the high pressure chamber cover 5 with the lower end of the casing 2 .

In the above embodiment, as shown in FIG. 5 , the cross-sectional shape of the opening of the sealing ring 9 along the axis is a trapezoid. match (as shown in Figure 8). When the low pressure chamber piston 12 moves downward, the first end 121 of the low pressure chamber piston 12 will press the sealing ring 9 .

In the above embodiment, as shown in FIG. 7 , the piston rod 72 of the high-pressure chamber piston 7 is provided with a first O-ring 73 , and the high-pressure chamber piston 7 is sealed and mounted to the high-pressure chamber 152 of the housing 2 through the first O-ring 73 . Inside.

In the above embodiment, as shown in FIG. 8 , a second O-ring 123 is provided on the piston rod 122 of the low-pressure chamber piston 12 , and the low-pressure chamber piston 12 is sealed and mounted to the piston of the locking stud 8 through the second O-ring 123 . intracavity.

The invention adopts the integral structure of the proportional pressure reducing valve to solve the problems of short service life and air leakage of the existing valve, and is suitable for long-term pressure reduction and inflation in the shock wave wind tunnel, with simple structure, easy processing and low manufacturing cost; and the invention adopts low pressure The cavity sealing film makes the sealing effect good; and the high-pressure cavity sealing film is used in the present invention to make the sealing effect good; and the material of the sealing ring used in the present invention is polytetrafluoroethylene material, which has a long service life; and the present invention has a simple structure and is easy to process and manufacture. ,low cost.

The above-mentioned embodiments are only preferred specific implementations of the present invention, and general changes and substitutions made by those skilled in the art within the scope of the technical solutions of the present invention should be included in the protection scope of the present invention.

Claims (8)

1. A proportional pressure reducing valve, characterized in that it comprises: a low-pressure chamber blocking cover (1), a casing (2), an air inlet connector (4), a high-pressure chamber blocking cover (5), a high-pressure chamber piston (7), a sealing ring (9), an air outlet joint (11) and a low pressure chamber piston (12); wherein, The low-pressure chamber blocking cover (1) is connected with one end of the casing (2), and the high-pressure chamber blocking cover (5) is connected with the other end of the casing (2); The low-pressure chamber blocking cover (1), the housing (2) and the high-pressure chamber blocking cover (5) form an internal cavity, wherein the cavity includes a low-pressure chamber (151) and a high-pressure chamber (152), The low pressure chamber (151) is communicated with the high pressure chamber (152); The sealing ring (9) is arranged at the communication position between the low pressure chamber (151) and the high pressure chamber (152), wherein the outer surface of the sealing ring (9) is in crimp contact with the inner wall of the housing (2); The low pressure chamber piston (12) is arranged in the low pressure chamber (151), and the outer side wall of the first end (121) of the low pressure chamber piston (12) can be crimped with the inner side wall of the sealing ring (9), The low-pressure cavity piston (12) can move up and down along the axis of the cavity; The high pressure chamber piston (7) is arranged in the high pressure chamber (152), the second end (71) of the high pressure chamber piston (7) and the first end (121) of the low pressure chamber piston (12) In contact, the high-pressure chamber piston (7) can move up and down along the axis of the cavity; One side of the casing (2) is provided with an air inlet joint (4), wherein the air inlet joint (4) is connected with the upper part of the high pressure chamber (152) through the first passage (41), and the air inlet joint (4) ) is connected with the lower end of the high pressure chamber (152) through the second passage (42); The other side of the housing (2) is provided with an air outlet joint (11), wherein the air outlet joint (11) is connected with the lower part of the low pressure chamber (151) through the third passage (111), and the air outlet joint (11) passes through The fourth channel (112) is connected with the upper end of the low pressure chamber (151); Wherein, the piston rod (72) of the high-pressure chamber piston (7) is provided with a first O-ring (73), and the piston rod (122) of the low-pressure chamber piston (12) is provided with a second O-ring (123); The cross-sectional shape of the low pressure chamber (151) along its axis is a T-shaped chamber, and the shape of the low pressure chamber piston (12) matches the shape of the low pressure chamber (151); The cross-sectional shape of the high-pressure chamber (152) along its axis is an inverted T-shaped chamber, and the shape of the high-pressure chamber piston (7) matches the shape of the high-pressure chamber (152). 2. The proportional pressure reducing valve according to claim 1, further comprising: a high-pressure chamber sealing film (6), wherein the high-pressure chamber sealing film (6) is arranged in the high-pressure chamber (152), and It is located at the lower part of the high pressure chamber piston (7). 3. The proportional pressure reducing valve according to claim 1, further comprising: a low pressure chamber sealing film (13), wherein the low pressure chamber sealing film (13) is arranged in the low pressure chamber (151), and Located on the upper part of the low pressure chamber piston (12). 4. The proportional pressure reducing valve according to claim 1, characterized in that, further comprising: a first bleed joint (3) and a second bleed joint (10); wherein, The first air release joint (3) is arranged on one side of the casing (2), and the first air release joint (3) communicates with the low pressure chamber through a fifth channel (31) opened by the casing (2). The first end (1511) of (151) is connected; The second air release joint (10) is arranged on the other side of the casing (2), and the second air release joint (10) communicates with the high pressure through the sixth channel (101) opened by the casing (2). The second end (1521) of the cavity (152) is connected. 5. The proportional pressure reducing valve according to claim 1, characterized in that, further comprising: a locking stud (8); wherein, The diameter of the bottom end of the low pressure chamber (151) is smaller than the diameter of the upper end of the high pressure chamber (152); The locking stud (8) is arranged in the high pressure chamber (152) and is threadedly connected with the inner wall of the housing (2); The diameter of the sealing ring (9) is equal to the diameter of the upper end of the high pressure chamber (152), one end of the sealing ring (9) is crimped with the bottom end of the low pressure chamber (151), and the sealing ring (9) ) is crimped with one end of the locking stud (8); The locking stud (8) is provided with a through cavity, and the second end (71) of the high pressure chamber piston (7) passes through the through cavity and the first end (121) of the low pressure chamber piston (12). ) are in contact. 6 . The proportional pressure reducing valve according to claim 1 , wherein the low-pressure chamber blocking cover ( 1 ) is connected to one end of the housing ( 2 ) through screws ( 14 ), and the high-pressure chamber blocking cover ( 2 ) is 6 . The cover (5) is connected with the other end of the casing (2) by screws (14). 7. The proportional pressure reducing valve according to claim 1, characterized in that, the cross-sectional shape of the opening of the sealing ring (9) along the axis is a trapezoid, and correspondingly, the first end of the low pressure chamber piston (12) The side wall of the head (121) is matched with the opening of the sealing ring (9). 8. The proportional pressure reducing valve according to claim 1, wherein the sealing ring (9) is a polytetrafluoroethylene sealing ring.