Piezoelectric pilot operated directional valve

Abstract

The utility model discloses a piezoelectric pilot type reversing valve. It mainly solves the problems of the existing reversing valve having a relatively large structure, occupying a large space and having a high cost. It is characterized in that: the two ends of the valve body (1) are respectively provided with a first piston chamber (6) and a second piston chamber (7), the two ends of the valve core (2) are respectively connected with a first piston (8) and a second piston (9), the area of ​​the first piston (8) is larger than the area of ​​the second piston (9), the first piston chamber (6) is externally connected with a piezoelectric valve (10), the valve body (1) is provided with an internal channel (12) communicating with a fluid inlet (3), one end of the internal channel (12) is communicated with the first piston chamber (6) through the piezoelectric valve (10), and the other end of the internal channel (12) is communicated with the second piston chamber (7). Compared with the prior art, the utility model eliminates the electromagnet, has a compact structure, occupies a small space, has a low cost, and has the characteristics of low noise, short response time, low power consumption and long continuous working time.

Description

Technical Field

[0001] The utility model relates to a reversing valve, in particular to a piezoelectric pilot type reversing valve. Background Art

[0002] A reversing valve is a control valve that has functions such as controlling fluid conduction, cutoff, reversing, pressure relief, and sequential action control. Existing reversing valves include a valve body and a valve core. The valve body is provided with a fluid inlet, a fluid outlet, and multiple working ports. The valve core can move in the valve body, and the fluid conduction, cutoff, reversing, pressure relief, and sequential action control functions are achieved through the position of the valve core. Among them, the sliding valve structure is commonly used. It is divided into two-position and three-position according to the number of working positions where the valve core stays in the valve body, and is divided into two-way, three-way, and four-way according to the number of working ports connected to the valve body. The ways to drive the valve core to move include manual, electric, hydraulic, and electro-hydraulic. In order to facilitate automatic control, electric reversing valves (also called electromagnetic reversing valves) are more common.

[0003] In recent years, with the development of science and technology, piezoelectric ceramics are used to sense changes in fluid pressure, and then the pressure change signal is converted into an electrical signal to control the operation of the pilot valve, and then the pilot valve controls the electromagnet to drive the valve core to move, so as to realize the automatic control of the reversing valve, such as a two-position reversing valve with a pilot function disclosed in Chinese patent 202110610135.X. This reversing valve has the following technical defects: piezoelectric ceramics only play the role of detecting pressure signals and are used to control the action of the pilot valve. Piezoelectric ceramics cannot directly control the movement of the valve core. The valve core drive device is still controlled by an electromagnet, which has a relatively large structure, occupies a large space, and has a high cost. Utility Model Content

[0004] In order to solve the technical problems existing in the prior art, the utility model provides a piezoelectric pilot reversing valve, which sets a piezoelectric valve as a pilot valve to control the position of the valve core in the reversing valve, thereby realizing the reversal of the medium passage. Compared with the prior art, the utility model eliminates the electromagnet, has a compact structure, occupies a small space, has low cost, and has the characteristics of low noise, short response time, low power consumption and long continuous working.

[0005] The technical solution of the utility model is: a piezoelectric pilot reversing valve, comprising a valve body and a valve core, the valve body is provided with a fluid inlet, a fluid outlet and a plurality of working ports, the valve core is located in the valve body and can slide relative to the valve body, the two ends of the valve body are respectively provided with a first piston cavity and a second piston cavity, the two ends of the valve core are respectively connected with a first piston and a second piston, the area of ​​the first piston is larger than that of the second piston, the first piston cavity is externally connected with a piezoelectric valve, the valve body is provided with an internal channel communicating with the fluid inlet, one end of the internal channel is communicated with the first piston cavity through the piezoelectric valve, and the other end of the internal channel is communicated with the second piston cavity. The piezoelectric valve includes a piezoelectric valve body and a piezoelectric ceramic sheet. The piezoelectric valve body is provided with a working chamber, a pilot working port, a pilot inlet and a pilot exhaust port. The piezoelectric ceramic sheet is located in the working chamber. The working chamber outside the piezoelectric ceramic sheet is communicated with the first piston chamber through the pilot working port. The piezoelectric ceramic sheet has two working states: blocking the pilot inlet and blocking the pilot exhaust port. Under normal conditions, the piezoelectric ceramic sheet blocks the pilot inlet. At this time, the first piston chamber, the pilot working port, the working chamber and the pilot exhaust port are communicated. After the piezoelectric ceramic sheet is energized, the piezoelectric ceramic sheet can bend and deform to detach from the pilot working port and block the pilot exhaust port. At this time, the first piston chamber, the pilot working port, the working chamber and the pilot inlet are communicated.

[0006] The piezoelectric ceramic sheet is covered with a rubber sleeve.

[0007] The pilot inlet and the pilot exhaust port protrude into the working chamber.

[0008] The two ends of the valve body are respectively connected with a first end cover and a second end cover, and the first piston chamber and the second piston chamber are respectively located in the first end cover and the second end cover.

[0009] The utility model has the following beneficial effects: Due to the adoption of the above technical solution, the utility model uses a piezoelectric valve as a pilot valve to control the position of the valve core in the reversing valve, thereby realizing the reversal of the medium passage. Compared with the prior art, the utility model eliminates the electromagnet, has a compact structure, occupies a small space, and has the following characteristics: 1. Low noise: The piezoelectric valve adopts piezoelectric ceramic deformation technology, which makes the piezoelectric valve completely silent during the single working process. The piezoelectric reversing valve using the piezoelectric valve as the pilot valve has lower working noise. 2. Faster response time: The response time of the piezoelectric valve is less than 2ms. The piezoelectric reversing valve using the piezoelectric valve as the pilot valve has a faster response time and improves work efficiency. 3. Lower power consumption: The maximum power consumption of the piezoelectric valve is 1mw. The piezoelectric reversing valve using the piezoelectric valve as the pilot valve has extremely low power consumption. The piezoelectric valve adopts the principle of capacitance. Almost no energy is required in the activated state. Only current is required at startup to charge the piezoelectric ceramic. No more energy is required when maintaining the state. 4. Sustainable operation: There are no heating elements in the piezoelectric valve used as a pilot valve. The piezoelectric valve generates almost no heat when working alone. This solves the problem of overheating of the pilot valve when the pilot reversing valve works for a long time. The piezoelectric reversing valve using a piezoelectric valve as a pilot valve has the characteristic of being able to work for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural sectional view of the utility model.

[0011] Figure 2 It is a structural sectional view of the medium-voltage electric valve 10 of the utility model.

[0012] Figure 3 The utility model is a working state diagram.

[0013] Figure 4 yes Figure 3 Enlarged view of point A in the middle.

[0014] Figure 5 This is a working state diagram of the utility model after reversing.

[0015] Figure 6 yes Figure 5 Enlarged view of point B in the middle.

[0016] In the figure: 1-valve body, 2-valve core, 3-fluid inlet, 4-fluid outlet, 5-working port, 6-first piston chamber, 7-second piston chamber, 8-first piston, 9-second piston, 10-piezoelectric valve, 11-end cover, 12-internal channel, 13-piezoelectric valve body, 14-piezoelectric ceramic sheet, 15-working chamber, 16-pilot working port, 17-pilot inlet, 18-pilot exhaust port, 19-rubber sleeve, 20-first end cover. DETAILED DESCRIPTION

[0017] The technical solution of the utility model is clearly and completely described below in conjunction with the accompanying drawings.

[0018] like Figures 1 to 6 As shown, a piezoelectric pilot reversing valve comprises a valve body 1 and a valve core 2, wherein the valve body 1 is provided with a fluid inlet 3, a fluid outlet 4 and a plurality of working ports 5, the valve core 2 is located in the valve body 1 and can slide relative to the valve body 1, a first piston chamber 6 and a second piston chamber 7 are respectively provided at both ends of the valve body 1, a first piston 8 and a second piston 9 are respectively connected at both ends of the valve core 2, the area of ​​the first piston 8 is larger than that of the second piston 9, the first piston chamber 6 is externally connected to a piezoelectric valve 10, an internal channel 12 communicating with the fluid inlet 3 is provided in the valve body 1, one end of the internal channel 12 is communicated with the first piston chamber 6 through the piezoelectric valve 10, and the other end of the internal channel 12 is communicated with the second piston chamber 7. The piezoelectric valve 10 includes a piezoelectric valve body 13 and a piezoelectric ceramic piece 14. The piezoelectric valve body 13 is provided with a working chamber 15, a pilot working port 16, a pilot inlet 17 and a pilot exhaust port 18. The piezoelectric ceramic piece 14 is located in the working chamber 15. The working chamber 15 outside the piezoelectric ceramic piece 14 is communicated with the first piston chamber 6 through the pilot working port 16. The piezoelectric ceramic piece 14 has two working states: blocking the pilot inlet 17 and blocking the pilot exhaust port 18. Under normal conditions, the piezoelectric ceramic piece 14 blocks the pilot inlet 17. At this time, the first piston chamber 6, the pilot working port 16, the working chamber 15 and the pilot exhaust port 18 are communicated. After the piezoelectric ceramic piece 14 is energized, the piezoelectric ceramic piece 14 can bend and deform to detach from the pilot working port 16 and block the pilot exhaust port 18. At this time, the first piston chamber 6, the pilot working port 16, the working chamber 15 and the pilot inlet 17 are communicated.

[0019] Due to the adoption of the above technical solution, when the pressure medium enters the fluid inlet 3, the medium is divided through the internal channel 12 and enters the pilot inlet 17 and the second piston chamber 7 of the piezoelectric valve 10 respectively. Under normal conditions, the pilot inlet 17 is blocked by the piezoelectric ceramic sheet 14, while the pilot exhaust port 18 is open, and the medium cannot enter the first piston chamber 6 through the piezoelectric valve 10. Because there is a pressure difference between the first piston chamber 6 and the second piston chamber 7, the medium pushes the valve core 2 to move toward the first piston chamber 6, and the medium on the rodless chamber side of the first piston chamber 6 is discharged through the pilot working port 16, the working chamber 15, and the pilot exhaust port 18; when the valve core 2 moves a certain distance, it reaches the working position, so that the fluid inlet 3 is connected to one working port 5, and the other working port 5 is connected to the fluid outlet 4. When the piezoelectric ceramic sheet 14 in the piezoelectric valve 10 is energized, the piezoelectric ceramic sheet 14 bends toward the pilot discharge port 18, the pilot inlet 17 is opened, the pilot discharge port 18 is blocked, and the medium enters the first piston chamber 6 from the pilot inlet 17 through the internal channel 12. Since the area of ​​the first piston 8 is larger than that of the second piston 9, under the action of the pressure difference, the medium pushes the valve core 2 to move toward the second piston chamber 7, and the medium on the rodless chamber side of the second piston chamber 7 flows back through the internal channel 12; when the valve core 2 moves a certain distance, it reaches the working position, and the fluid inlet 3 and the working port 5 are switched to achieve reversal. The utility model uses the piezoelectric valve 10 as a pilot valve to control the position of the valve core in the reversing valve, thereby achieving the reversal of the medium passage. Compared with the prior art, the utility model eliminates the electromagnet, has a compact structure, occupies a small space, and has the following characteristics: 1. Low noise: The piezoelectric valve 10 adopts piezoelectric ceramic deformation technology, which makes the piezoelectric valve 10 completely silent during the single working process. The piezoelectric reversing valve using the piezoelectric valve as the pilot valve has lower working noise. 2. Faster response time: The response time of the piezoelectric valve 10 is less than 2ms. The piezoelectric reversing valve using the piezoelectric valve 10 as the pilot valve has a faster response time and improves working efficiency. 3. Lower power consumption: The maximum power consumption of the piezoelectric valve 10 is 1mw. The piezoelectric reversing valve using the piezoelectric valve 10 as the pilot valve has extremely low power consumption. The piezoelectric valve 10 adopts the principle of capacitance. It requires almost no energy in the activated state. It only requires current at startup to charge the piezoelectric ceramic. When maintaining the state, no more energy is required. 4. Sustainable operation: There is no heating element in the piezoelectric valve 10 as a pilot valve. The piezoelectric valve 10 generates almost no heat when working alone. This solves the problem of overheating of the pilot valve when the pilot reversing valve works for a long time. The piezoelectric reversing valve using the piezoelectric valve 10 as the pilot valve has the characteristic of being able to work for a long time.

[0020] The piezoelectric ceramic sheet 14 is covered with a rubber sleeve 19. The rubber sleeve 19 can achieve a better sealing effect between the piezoelectric ceramic sheet 14 and the pilot inlet 17 and the pilot exhaust port 18.

[0021] The pilot inlet 17 and the pilot exhaust port 18 protrude into the working chamber 15. This structure enables the piezoelectric ceramic sheet 14 to leave the working chamber 15 when blocking the pilot inlet 17 and the pilot exhaust port 18. The distance between the pilot inlet 17 and the pilot exhaust port 18 is designed according to the deformation of the piezoelectric ceramic sheet 14 to achieve the best blocking effect.

[0022] The two ends of the valve body 1 are respectively connected with a first end cover 20 and a second end cover 11, and the first piston chamber 6 and the second piston chamber 7 are respectively located in the first end cover 20 and the second end cover 11. The first end cover 20 and the second end cover 11 are made of non-metallic materials, which are easy to process and have low processing costs.

Claims

1. A piezoelectric pilot-operated reversing valve, comprising a valve body (1) and a valve core (2), wherein the valve body (1) is provided with a fluid inlet (3), a fluid outlet (4) and a plurality of working ports (5), and the valve core (2) is located in the valve body (1) and can slide relative to the valve body (1), characterized in that: The two ends of the valve body (1) are respectively provided with a first piston chamber (6) and a second piston chamber (7); the two ends of the valve core (2) are respectively connected with a first piston (8) and a second piston (9); the area of ​​the first piston (8) is larger than the area of ​​the second piston (9); the first piston chamber (6) is externally connected to a piezoelectric valve (10); an internal channel (12) communicating with a fluid inlet (3) is provided in the valve body (1); one end of the internal channel (12) is communicated with the first piston chamber (6) through the piezoelectric valve (10); the other end of the internal channel (12) is communicated with the second piston chamber (7); the piezoelectric valve (10) comprises a piezoelectric valve body (13) and a piezoelectric ceramic sheet (14); the piezoelectric valve body (13) is provided with a working chamber (15), a pilot working port (16), a pilot inlet (17) and a pilot exhaust port (18); The piezoelectric ceramic piece (14) is located in the working chamber (15), and the working chamber (15) outside the piezoelectric ceramic piece (14) is communicated with the first piston chamber (6) through the pilot working port (16). The piezoelectric ceramic piece (14) has two working states: blocking the pilot inlet (17) and blocking the pilot discharge port (18). Under normal conditions, the piezoelectric ceramic piece (14) blocks the pilot inlet (17), and at this time, the first piston chamber (6), the pilot working port (16), the working chamber (15) and the pilot discharge port (18) are communicated. After the piezoelectric ceramic piece (14) is energized, the piezoelectric ceramic piece (14) can bend and deform to detach from the pilot working port (16) and block the pilot discharge port (18), and at this time, the first piston chamber (6), the pilot working port (16), the working chamber (15) and the pilot inlet (17) are communicated.

2. A piezoelectric pilot-operated reversing valve according to claim 1, characterized in that: The piezoelectric ceramic sheet (14) is covered with a rubber sleeve (19).

3. A piezoelectric pilot-operated reversing valve according to claim 1, characterized in that: The pilot inlet (17) and the pilot exhaust port (18) protrude into the working chamber (15).

4. A piezoelectric pilot-operated reversing valve according to claim 1, characterized in that: The two ends of the valve body (1) are respectively connected to a first end cover (20) and a second end cover (11); the first piston chamber (6) and the second piston chamber (7) are respectively located in the first end cover (20) and the second end cover (11).

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