JPH11257510A - Four-way selector valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To retain tension constant as a piston seal by slantly cutting the piston seal, and improve sealed properties in a wide range from a high temperature period to a low temperature period. SOLUTION: In this four-way selector valve in which a valve slide is laterally slid under a pressure contact condition on the upper surface of a valve seat arranged in the inside of a tubular main body by being interlocked with a piston 1 around which resin seal rings 33, 34 are fitted, the resin seal rings 33, 34 are equipped with cut parts 33a, 34a that a part of the peripheral parts of the resin seal rings 33, 34 are slantly cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a four-way switching valve used for switching between cooling and heating of a heat pump type air conditioner, for example, by cutting a resin seal ring of a piston obliquely to reduce leakage of refrigerant particularly at a low temperature. In addition, the present invention relates to a four-way switching valve which is easy to assemble a piston and inexpensive.

[0002]

2. Description of the Related Art The applicant of the present invention has proposed a four-way switching valve which is easy to assemble by simplifying the structure of a piston. FIG. 3 is a longitudinal sectional view of a conventional four-way switching valve disclosed in Japanese Patent Application Laid-Open No. 9-229214, and shows a state where it is arranged in a refrigeration circuit during cooling. The tubular body 10 is a cylindrical tube, which has three conduits 1 in the axial direction.
1, 12 and 13 are provided so as to communicate with each other, and a surface facing the three conduits 11, 12 and 13 is provided so as to communicate with one conduit 14. In addition, a guide port 20 and a guide port 26 are provided near both ends of the tubular main body 10, respectively. Then, a dish-shaped lid 15 is fixed to the left side of the tubular body 10, and the sliding surface 16 of the right seal portion is deep-drawn on the right side.
a and a lid 16 formed with a stopper 16b of the piston 1 are fixed. The conduit 11 communicates with the indoor heat exchanger 17, the conduit 13 communicates with the outdoor heat exchanger 18, and the conduit 14
Communicates with the discharge side of the compressor 19, the conduit 12 communicates with the suction side of the compressor 19, the conduit 20 communicates with the conduit 12, and the conduit 26 communicates with the solenoid valve 25.

On the other hand, in the inside of the tubular body 10, there are provided holes communicating with the three conduits 11, 12, and 13, respectively.
An inverted crab-shaped valve seat 2 having an upper surface formed with a sliding surface 21a and a lower surface curved along the inner surface of the tubular body 10.
1 is provided. A bowl-shaped valve slide 22 is provided on the upper surface of the valve seat 21 so as to straddle at least two of the three conduits 11, 12, and 13. Built in. Further, a leaf spring 24 is provided between the valve slide 22 and the connecting plate 2 so that the valve slide 22 does not rotate and comes into close contact with the upper surface of the valve seat 21 even when the piston 1 tries to rotate in the circumferential direction. Has become.

[0004] The pilot solenoid valve 25 is a three-way valve,
In the non-energized state, the conduit 12 communicates with the conduit 26, the piston 1 moves to the left along with the valve slide 22, and the refrigerant flows from the compressor 19 → the conduit 14 → the conduit 13 → the outdoor heat exchanger 18 → the throttling device 27 → It circulates in the order of the indoor heat exchanger 17 → the conduit 11 → the conduit 12 → the compressor 19. Also,
In an energized state, the conduit 14 communicates with the conduit 26 and the piston 1
Moves rightward with the valve slide 22, and the refrigerant is
Compressor 19 → conduit 14 → conduit 11 → indoor heat exchanger 17 → throttling device 27 → outdoor heat exchanger 18 → conduit 13
→ Circulate 12 → Compressor 19 Note that the above-described system and structure are exactly the same as conventional products.

FIG. 4 is a longitudinal sectional view showing a piston 1 of a conventional four-way switching valve. The piston 1 has a seal portion 31 and a seal portion 3 each formed in a round shaft shape at both ends.
2 and the connecting plate 2 are integrated by resin molding, die casting or the like, and the resin seal rings 33, 34 are fitted into the seal grooves 31a, 32a.

[0006]

However, in the piston of such a conventional four-way switching valve, since the resin seal rings 33 and 34 have an endless shape, the outer peripheral portion of the resin seal ring is subject to changes in ambient temperature. The expansion and contraction are repeated following. That is, since the temperature is directly affected by the coefficient of linear expansion, there is a problem that leakage increases due to shrinkage, particularly on the low temperature side.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and is characterized in that a part of the outer periphery of a resin seal ring of a piston 1 is cut obliquely. Provide a piston seal.

That is, in the four-way switching valve according to the present invention, the valve slide 22 is pressed against the upper surface of the valve seat 21 disposed inside the tubular body 10 in conjunction with the piston 1 on which the resin seal rings 33 and 34 are fitted. In the four-way switching valve that slides left and right in the state, the resin seal ring 33,
34 is a cutting portion 33 obtained by diagonally cutting a part of the outer peripheral portion.
a, 34a.

The diagonally cut portions 33a, 34a of the resin seal rings 33, 34 are formed in a step-like manner in the four-way switching valve according to claim 1.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A four-way switching valve according to the present invention will be described below. The configuration used in a refrigeration circuit is the same as that of the conventional one shown in FIG. Except for the piston 1, the other components are the same, and detailed description thereof will be omitted.

FIG. 1 shows a piston 1 of a four-way switching valve according to the present invention.
FIG. The piston 1 is provided with a hole 2b for fitting the valve slide 22 in the center, and a seal portion 31 having seal grooves 31a and 32a on the outer peripheral portions arranged on the left and right.
And a seal portion 32.

The seal grooves 31a and 32a have:
Resin seal rings 33 and 34 are fitted. In addition,
Diagonal cut portions 33a and 34a are provided on a part of the outer periphery of the resin seal rings 33 and 34, and can be fitted into the seal grooves 31a and 32a by expanding the cut portions.

FIG. 2 is a perspective view showing another embodiment of the resin seal ring, in which the outer peripheral cut portions 33a and 34a of the resin seal ring 33 (34) are formed in a step-like manner. The cut portion is generally called an abutment, and can have various shapes to control the amount of leakage.

[0014]

As described above, according to the present invention, the seal grooves 31a and 32a are formed on the outer peripheral surfaces of the seal portions 31 and 32 disposed on the left and right sides of the piston 1, and the outer peripheral portions are formed in the grooves. Since the resin seal rings 33 and 34 whose parts have been cut are fitted, a four-way switching valve that is easy to assemble and inexpensive compared to conventional products can be provided. Also,
Since a part of the outer peripheral portion of the resin seal rings 33 and 34 is cut, the amount of expansion and contraction due to a change in the surrounding temperature is absorbed by the cut portion, so that the tension force as the piston seal becomes constant and the The practical effect that the sealing property can be improved over a wide range from low to low temperatures is great.

[Brief description of the drawings]

FIG. 1 is a perspective view of a piston showing an embodiment of the present invention.

FIG. 2 is a perspective view of a resin seal ring showing another embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a conventional four-way switching valve showing a refrigeration circuit diagram during cooling.

FIG. 4 is a perspective view of a conventional piston.

[Explanation of symbols]

1 piston, 2 connecting plate, 2
b Fitting hole for valve slide, 10 tubular body, 2
1 valve seat, 22 valve slide, 31, 32 seal part, 31a, 3
2a seal groove, 33, 34 resin seal ring,
33a, 34a oblique cutting section

Claims (2)

[Claims] 1. A valve slide (22) interlocks with a piston (1) on which resin seal rings (33, 34) are fitted.
In a four-way switching valve that slides left and right in a press-contact state on the upper surface of the valve seat 21 disposed inside the resin seal ring 33, the resin seal rings 33 and 34 have cut portions 33a obtained by cutting a part of the outer peripheral portion obliquely, 34a, comprising a four-way switching valve. 2. The four-way switching valve according to claim 1, wherein the oblique cut portions 33a, 34a of the resin seal rings 33, 34 are formed in a stepped manner.