JP2000046214A - Four-way switching valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the sealability in an extensive range from a high temperature to a low temperature by internally pressing a rubber ring against the inner side of a resin seal ring to stably keep the tension of the seal surface. SOLUTION: In this four-way switching valve in which a valve slide slides in the right-to-left direction in a pressed condition against an upper surface of a valve seat arranged inside a tubular body in an interlocking manner with a piston to which resin seal rings 34, 36 are attached, rubber rings 33, 35 are attached to seal grooves 31a, 32a of the piston 1, and the resin seal rings 34, 36 are attached to the outside of the rubber rings 33, 35.

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, in which a rubber ring is fitted to an inner surface of a resin seal ring of a piston, and particularly, refrigerant leakage at a low temperature. The present invention relates to a four-way switching valve for reducing the number of valves.

[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. 2 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 in which 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, and 13 are provided so as to communicate with each other, and one conduit 14 is provided so as to communicate with a surface facing the three conduits 11, 12, and 13. 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
Is in communication with the discharge side of the compressor 19, the conduit 12 is in communication with the suction side of the compressor 19, the outlet 20 is in communication with the conduit 12, and the outlet 26 is in communication with the solenoid valve 25.

On the other hand, inside 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. 3 is a longitudinal sectional view showing a piston 1 of a conventional four-way switching valve. The piston 1 has seal portions 31 and 32 formed at both ends in a round shaft shape and a connecting plate 2 respectively.
Are integrated by resin molding, die casting or the like, and resin seal rings 34, 36 are fitted in the seal grooves 31a, 32a.

[0006]

However, in such a conventional piston of a four-way switching valve, since the resin seal rings 34 and 36 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. In other words, since the temperature is directly affected by the coefficient of linear expansion, there is a problem that the leakage of the refrigerant increases particularly due to the contraction on the low temperature side.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is characterized in that a rubber ring is inscribed inside a resin seal ring of a piston 1. To 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 fitted with the resin seal rings 34, 36. In the four-way switching valve that slides left and right in the state, the seal groove 31 of the piston 1
A and 32a are fitted with rubber rings 33 and 35, and resin seal rings 34 and 36 are fitted outside the rubber rings 33 and 35.

[0009]

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 the conventional one shown in FIG. 2, and the configuration of the four-way switching valve is also described. 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 3 having seal grooves 31a and 32a on the outer peripheral portions arranged on the left and right.
1 and 32.

The seal grooves 31a and 32a have
Rubber rings 33 and 35 are fitted, and resin seal rings 34 and 36 circumscribing the rubber rings 33 and 35 are fitted.

[0012]

As described above, according to the present invention, the rubber rings 33, 32a are provided in the seal grooves 31a, 32a provided on the outer peripheral surfaces of the seal portions 31, 32 disposed on the left and right sides of the piston 1.
35 and the resin seal rings 34 and 36 fitted on the outside thereof, the elastic action of the rubber rings 33 and 35 causes the resin seal ring 3 due to a change in ambient temperature.
The rubber ring absorbs the amount of expansion and contraction of 4, 36, so that the tension force as a piston seal is stabilized, and the practical effect that the sealing property can be improved over a wide range from high to low temperatures is great. It becomes.

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

FIG. 3 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
DESCRIPTION OF SYMBOLS 1 Valve seat, 22 Valve slide, 31, 32 Seal part, 31a, 3
2a seal groove, 33, 35 rubber ring,
34,36 resin seal ring

Claims (1)

[Claims] The valve slide (22) interlocks with the piston (1) on which the resin seal rings (34, 36) 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 valve ring 21, rubber rings 33 and 35 are fitted into the seal grooves 31 a and 32 a of the piston 1, and , 35 fitted with resin seal rings 34, 36 outside.