Non-leak three-way valve

Abstract

To provide a non-leak three-way valve capable of high precision processing and suitably preventing leakage of working fluid when a selector valve is switched.SOLUTION: A typical configuration of a non-leak three-way valve according to the present invention includes: a sleeve 110; a P port, an A port and a T port that are provided on the sleeve; and a shaft 120 that slides in the sleeve to switch communication of the P port, the A port and the T port. The shaft 120 has a poppet part 124 to switch a communication destination of the A port to the P port or the T port. The poppet part 124 has conical surfaces 126a, 126b at both ends and a cylinder surface 128 arranged between the conical surfaces. The sleeve 110 has valve seats 112a, 112b on both sides of the A port that contact with the poppet part, and diaphragm surfaces 114a, 114b arranged between the valve seats and the A port so as to face against the cylinder surface of the poppet part to form a diaphragm.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a non-leak three-way valve. [Background technology]

[0002] Switching valves are used in industrial facilities to control the supply of working fluid. Among them, switching valves that switch between three ports, such as P port, A port, and T port, are called three-way valves.

[0003] As an example of a switching valve, Patent Document 1 discloses "a solenoid valve for an adsorption type oxygen concentrator having a pair of valve seats arranged opposite each other in a valve chamber, a common port communicating with the valve chamber between both valve seats, a pair of selection ports outside both valve seats communicating with the valve chamber, and a valve element selectively abutted against both valve seats by an electromagnetic actuator."

[0004] In particular, the solenoid valve for an adsorption-type oxygen concentrator in Patent Document 1 is characterized in that "on both sides of the valve element, there are provided poppet valve seats that are received on the respective valve seats, and spool portions that protrude from the outer end surfaces of the poppet valve seats and are inserted into and removed from valve holes in the valve seats." The valve element is characterized in that "both spool portions are formed so that when the valve element is positioned at the center between the two valve seats, they protrude into the respective valve holes in a sealing manner over a predetermined overlapping dimension, and when the valve element is displaced from the center between the two valve seats by more than a predetermined amount toward any one of the valve seats, the other valve seat opens." [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Utility Model Registration Publication No. 2594442 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the spool portion and the poppet valve seat are continuously connected, with the spool portion located on the inner diameter side of the poppet valve seat. Therefore, when grinding the poppet valve seat (inclined surface) with a grinding wheel or the like, the machining tool interferes with the spool portion (cylindrical surface), making it difficult to machine with precision. Therefore, the solenoid valve for an adsorption-type oxygen concentrator in Patent Document 1 is difficult to manufacture, raising concerns about increased costs. Furthermore, in the configuration of Patent Document 1, the sliding surface of the spool portion is located near the poppet valve seat. Therefore, if the valve seat is struck and deformed toward the inner diameter, the clearance of the spool portion disappears, which could result in contact and sticking.

[0007] In view of these problems, the present invention aims to provide a non-leak three-way valve that can be machined with high precision and that can effectively prevent leakage of working fluid when the switching valve is switched. [Means for solving the problem]

[0008] In order to solve the above problems, a typical configuration of a non-leak three-way valve according to the present invention comprises a sleeve (outer cylinder), a P port (pump port), an A port (output port), and a T port (tank port) provided on the sleeve, and a shaft that slides inside the sleeve to switch the communication of the P port, A port, and T port, the shaft having a poppet portion that switches the communication destination of the A port to either the P port or the T port, the poppet portion having conical surfaces on both ends and a cylindrical surface located between the conical surfaces, and the sleeve having valve seats on both sides of the A port that come into contact with the poppet portion, and throttling surfaces (inner circumferential surfaces) that are located between the valve seats and the A port and face the cylindrical surfaces of the poppet portion to form a throttling.

[0009] The width of the cylindrical surface is preferably greater than the width of the A port.

[0010] The shaft may have a pair of spool portions outside the P port and the T port to prevent leakage of the working fluid, and the clearance between the cylindrical surface and the throttle surface may be larger than the clearance between the spool portions and the sleeve. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a non-leak three-way valve that can be machined with high precision and that can suitably prevent leakage of working fluid when the switching valve is switched. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram illustrating a non-leak three-way valve according to an embodiment of the present invention. FIG. [Figure 2] FIG. 10 is a diagram illustrating a state in which the PAs are about to open up. [Figure 3] FIG. 10 is a diagram illustrating a state in which the shaft is in a mid-position. [Figure 4] This is a diagram illustrating the state in which the AT gap is about to close. DETAILED DESCRIPTION OF THE INVENTION

[0013] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Dimensions, materials, and other specific values ​​shown in the embodiments are merely examples for facilitating understanding of the invention and, unless otherwise specified, do not limit the present invention. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

[0014] Fig. 1 is a diagram illustrating a non-leak three-way valve 100 according to this embodiment. Fig. 2 is a diagram illustrating a state in which the PA section is about to open, Fig. 3 is a diagram illustrating a state in which the shaft is in an intermediate position (transitional period), and Fig. 4 is a diagram illustrating a state in which the AT section is about to close.

[0015] 1, the non-leak three-way valve 100 of this embodiment includes a sleeve 110 that functions as an outer cylinder, and a shaft 120 that slides inside the sleeve 110. The sleeve 110 is provided with a P port (pump port P), an A port (output port A), and a T port (tank port T).

[0016] The shaft 120 slides within the sleeve 110, thereby switching between communicating the P port with the A port or communicating the A port with the T port. The shaft 120 has a pair of spool portions 122a, 122b (also called lands) outside the P port and the T port to prevent leakage of the working fluid.

[0017] The shaft also has a poppet portion 124 between the pair of spool portions 122a, 122b that switches the communication destination of the A port. The poppet portion 124 is similar to a land and is a large-diameter portion of the shaft 120. The poppet portion 124 has conical surfaces 126a, 126b (which form poppet-type valve bodies) on both ends (the end on the P port side and the end on the T port side), and a cylindrical surface 128 that is located between the conical surfaces 126a, 126b.

[0018] On the other hand, the sleeve 110 has valve seats 112a and 112b and throttle surfaces 114a and 114b. The valve seats 112a and 112b are disposed on both sides of the A port and are in contact with the poppet portion 124 of the shaft 120.

[0019] The throttle surfaces 114a, 114b (inner peripheral surfaces) are disposed between the valve seats 112a, 112b and the A port, and are portions that face a cylindrical surface 128 of the poppet portion 124 to form a throttle. The clearance (gap) between the cylindrical surface 128 and the throttle surface 114 may be larger than the clearance between the spool portions 122a, 122b (sliding surfaces) and the sleeve 110. The cylindrical surface 128 is intended to form a two-stage throttle.

[0020] Furthermore, the width W2 of the cylindrical surface 128 is formed to be longer than the width W1 of the A port. Therefore, when the shaft 120 moves, the cylindrical surface 128 always overlaps with either the throttle surface 114a or 114b. This prevents the P port from communicating with the T port when the shaft 120 is in an intermediate position (transition period), thereby reducing leakage of the working fluid.

[0021] In the state illustrated in Fig. 2(a), the conical surface 126a of the shaft 120 is in contact with the valve seat 112a of the sleeve 110. Therefore, the P port is blocked, and the A port and the T port are connected. At this time, as shown in Fig. 2(c), the opening area G0 of the PA path is 0, and the opening area G1 of the AT path is at its largest.

[0022] In the state illustrated in Figure 2(b), the shaft 120 slides in the sleeve 110 toward the T port. This prevents contact between the conical surface 126a of the shaft 120 and the valve seat 112a of the sleeve 110. At this time, as shown in Figure 2(d), the opening area G2 of the PA path is slightly larger than in Figure 2(c), and the opening area G3 of the AT path is slightly smaller than in Figure 2(c).

[0023] In the state illustrated in Figure 3(a), the shaft 120 continues to slide within the sleeve 110 toward the T port. When the gap between the conical surface 126a and the valve seat 112a becomes wider than the gap between the cylindrical surface 128 and the throttle surface 114a, a throttle with an opening area G4 is formed between the cylindrical surface 128 and the throttle surface 114a. At this time, as shown in Figure 3(c), the opening area G5 of the AT path becomes even smaller. The opening area G4 of the PA path remains constant while the cylindrical surface 128 and the throttle surface 114a overlap.

[0024] In the state illustrated in Fig. 3(b), the shaft 120 slides further toward the T port inside the sleeve 110. As a result, the cylindrical surface 128 of the shaft 120 faces both of the throttling surfaces 114a and 114b of the sleeve 110, forming throttling. At this time, as shown in Fig. 3(d), the PA path and the AT path have approximately the same opening area G4.

[0025] In the state illustrated in Figure 4(a), the shaft 120 slides further inside the sleeve 110 toward the T port, causing the cylindrical surface 128 of the shaft 120 to move away from the throttle surface 114a of the sleeve 110. As a result, a throttle is formed only between the cylindrical surface 128 of the shaft 120 and the throttle surface 114b of the sleeve 110. At this time, as shown in Figure 4(b), the opening area of ​​the AT path is a substantially constant opening area G4, and the opening area G6 of the PA path gradually increases.

[0026] In the state illustrated in Figure 4(b), the conical surface 126b is in contact with the valve seat 112b. This blocks the T port, and maximizes communication between the A port and the P port. At this time, as shown in Figure 4(d), the opening area G0 of the AT path is 0, and the opening area G7 of the PA path is at its largest.

[0027] As described above, according to the non-leak three-way valve 100 of this embodiment, by forming a restriction using the restriction surfaces 114a, 114b and the cylindrical surface 128, it is possible to dramatically reduce leakage of working fluid when the non-leak three-way valve 100 is switched (transition period).

[0028] In the non-leak three-way valve 100 of this embodiment, the cylindrical surface 128 is located closer to the outer periphery than the conical surfaces 126a and 126b. This prevents the machining tool from interfering with the cylindrical surface 128 when polishing the conical surfaces 126a and 126b. This allows for high-precision machining.

[0029] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that such modifications and alterations also fall within the technical scope of the present invention. [Industrial Applicability]

[0030] The present invention can be used as a non-leak three-way valve. [Explanation of symbols]

[0031] 100...Non-leak three-way valve, 110...Sleeve, 112a...Valve seat, 112b...Valve seat, 114a...Throttling surface, 114b...Throttling surface, 120...Shaft, 122a...Spool portion, 122b...Spool portion, 124...Poppet portion, 126a...Conical surface, 126b...Conical surface, 128...Cylindrical surface

Claims

1. Sleeve and a P port, an A port, and a T port provided on the sleeve; a shaft that slides in the sleeve to switch communication between the P port, the A port, and the T port; Equipped with the shaft has a poppet portion that switches the communication destination of the A port between the P port and the T port, The poppet portion has conical surfaces at both ends and a cylindrical surface disposed between the conical surfaces, a sleeve having valve seats on both sides of the A port that come into contact with the poppet portion, and a throttle surface that is disposed between the valve seats and the A port and faces the cylindrical surface of the poppet portion to form a throttle.

2. 2. The non-leak three-way valve according to claim 1, wherein the width of the cylindrical surface is greater than the width of the A port.

3. the shaft has a pair of spool portions on the outside of the P port and the T port to prevent leakage of the working fluid, 2. The non-leak three-way valve according to claim 1, wherein a clearance between the cylindrical surface and the throttle surface is larger than a clearance between the spool portion and the sleeve.

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