JPS6287775A - Expansion valve for reversible refrigeration cycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an expansion valve for a reversible refrigeration cycle used in a dual purpose air conditioner.

[Conventional technology]

All conventional expansion valves control the flow rate of refrigerant by controlling the opening degree of the valve, so they require small capacity refrigerant control, such as in refrigerators, and are difficult to operate in places with small Reynolds numbers. In devices that require fluid control, there is a problem in that even if the valve position is maintained at a certain position, the flow rate changes due to changes in the viscosity of the fluid and cannot be controlled.

Therefore, the applicant does not control the flow rate by the opening degree of the valve, but by the opening time of the valve.
The flow rate of fluid passing through the solenoid valve is controlled by duty cycle control, which applies a pulse with a constant repetition period to a solenoid valve that operates on and off by pulses, and changes the width of this pulse to change the on-time of the solenoid valve. We are developing control technology (Japanese Patent Laid-Open No. 57-204381).

[Problem that the invention seeks to solve]

By the way, if we try to apply the above flow rate control technology to the expansion valve in a reversible refrigeration cycle of an automobile air conditioner, etc., when the refrigerant flows back, pressure fluctuations on the high pressure side will affect the opening and closing force of the valve, making accurate control impossible. It becomes impossible.

The present invention has been made with attention to the above-mentioned points, and is a reversible device that makes it possible to control the opening and closing of a valve according to the duty cycle while eliminating the influence of high pressure fluctuations on the opening and closing control of the valve. The present invention provides an expansion valve for a refrigeration cycle.

[Means for solving problems]

In order to achieve the above object, in the present invention, a partition wall that partitions the communication port and the valve chamber at one side of the communication port and a partition wall that partitions the communication port and the other communication port are provided facing each other. A valve port is formed in one partition wall, and a sliding guide hole is formed in the other partition wall, and the valve port is formed at the end of a cylindrical plunger that reciprocates between the attractor of the electromagnet and the valve port. The valve body to be opened and closed is supported in a state in which it is movable in the axial direction and partially protrudes, and the valve body is biased in the valve closing direction by a spring provided between the suction element and inserted into the sliding guide hole. A differential pressure eliminating rod having approximately the same diameter as the valve port is slidably supported, and the differential pressure eliminating rod is connected to the valve body, and a seal nozzle provided around the differential pressure eliminating rod is provided. Structure B' (2) is formed by applying pressure with a spring to close the cough sliding guide hole with the pointed head of the seal bar, and forming a passage in the communication port on the 10 side and the valve chamber.

It was adopted.

〔Example〕

In FIG. 1, reference numeral 1 denotes an abbreviated expansion valve main body, in which a flow port A and a flow port B are formed. At the inner end of the flow port A, a partition wall 2 having a valve port 2a between the valve chamber C and a partition wall 3 having a sliding guide hole 3a between the flow port B and the flow port B is provided to face each other. The valve [-12a and the sliding guide hole 3a are arranged so that their centers coincide, and the ball valve body 4 is located in the valve chamber C.
comes into contact with and separates from the valve seat 2b. A valve port 2 is provided in the sliding guide hole 3a.
A differential pressure eliminating loft 5 formed to have approximately the same diameter as a is slidably supported, and the differential pressure eliminating rod 5 is fixed to the ball valve body 4 from the valve port 2a with a narrow diameter portion 5a by welding means. Ru.

In the partition wall 3, the sliding guide hole 3a has a tapered portion 3b.
A large-diameter gasket housing hole 3C is formed through the gasket housing hole 3C, and a seal gasket 6 made of a hard synthetic resin such as Teflon is fitted around the differential pressure elimination loft 5 through a hole 6a in the gasket housing hole 3C. and the seal packing 6 is connected to the flow port B.
The slide guide hole 3a is pressurized by a spring 8 installed between the support plate 7 and the support 7 provided in the slide guide hole 3a. The seal packing 6 has a pointed head 6b, and when pressurized, the pointed head 6b is brought into pressure contact with the periphery of the differential pressure eliminating rod 5 under the action of the tapered part 3b. The differential pressure eliminating rod 5 is in pressure contact with the differential pressure eliminating rod 5 at the portion thereof.
To seal a sliding guide hole 3a without interfering with smooth movement of the slide guide hole 3a.

In the valve body 1, a through hole 9 is formed between the flow port B and the valve chamber C.

A plunger tube 10 is erected in the valve chamber C, and an electromagnetic attractor 11 is fixed to the upper end of the plunger tube 10.

A U-shaped outer case 12 made of magnetic material is fixed to the attractor 11 by a port 13, and an electromagnetic coil 1 wound around a flanged hollow pobbin 14 is placed between the opposing pieces of the outer case 12.
5 is being held.

A tubular plunger 16 made of a magnetic material is slidably housed in the plunger tube 10, and a support hole 16a that narrows downward is formed at the end opposite the valve port 2a. At 16a, the ball valve body 4 is supported in such a manner that it is movable inwardly of the plunger 6 and partially protrudes outward. A spring receiver 17 is movably provided on the plunger 16.
The compression spring 18 provided between the suction element 11 and the suction element 11 urges the ball valve body 4 in the direction of protruding from the support hole 16a of the plunger 16.

Note that 19 is a lead wire for supplying a pulse current to the electromagnetic coil 15.

In the above configuration, during the cooling operation, the refrigerant flows from the circulation port A to the circulation port B through the valve port 2a and the valve chamber C1 through hole 9, and conversely flows from the circulation port B to the circulation port A during the heating operation. At this time, a pulse current is passed through the lead wire 19 and the electromagnetic coil 15 is excited, so that the plunger 16 is attracted by the attractor 11 and the ball valve body 4 is moved to the valve seat 2.
Pull away from b.

The operation of the solenoid valve configured as described above is shown in Figures 2 (al to (C)).
Explain with reference to.

FIG. 2 (al indicates the valve open state, the plunger 16 is in contact with the partition wall 2 due to its own weight, and the ball valve body 4 is in pressure contact with the valve seat 2b by the action of the compression spring 18. In this state, the electromagnetic coil 15, the plunger 16 is attracted by the attractor 11, but the I
Since no load is applied to the plunger 16 during I to open the valve, the distance 1° acts as a shock interval to increase the force for opening the valve.

After that, the plunger 16 supports the ball valve body 4 and moves to a distance 12 shown in FIG. 2(C), and becomes fully open.

As described above, the present invention applies a pulse with a constant repetition period to a solenoid valve that is turned on and off by pulses, and changes the width of the pulse to change the ON time of the solenoid valve, thereby controlling the flow rate of the fluid. In the expansion valve for controlling the flow rate, a partition wall that partitions the flow port and the valve chamber at one side of the flow port and a partition wall that separates the flow port and the other flow port are provided facing each other, and a valve port is provided in one of the flow ports. At the same time, a sliding guide hole is formed in the other partition wall, and a valve body that opens and closes the valve port is axially moved at the end of a cylindrical plunger that reciprocates between the attractor of the electromagnet and the valve port. It is supported in a state where it is movable and partially protrudes,
A spring provided between the suction element urges the valve element in the valve closing direction, and a differential pressure eliminating rod having approximately the same diameter as the valve opening is slidably supported in the sliding guide hole. A differential pressure eliminating rod is connected to the valve body, a seal gasket provided around the differential pressure eliminating rod is pressurized by a spring to close the sliding guide hole with the pointed end of the seal gasket, and the other Since the valve has a flow port and a passage within the valve chamber, the differential pressure elimination rod connected to the valve body prevents high pressure fluctuations from affecting the opening and closing of the valve, ensuring accurate flow during both reversible and closed flow. It has the advantage that it is possible to achieve good control, and at this time, the seal packing can prevent leakage of the refrigerant.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention, and FIG. 2 (
al (b) (e) are cross-sectional views for explaining the operation. A, B...Flow port, C...Valve chamber, D...Electromagnet,
2゜3... opposing partition walls, 2a... valve port, 3a...
...Sliding guide hole, 4...Valve body, 5...Differential pressure elimination rod, 6...Seal packing, 8...Spring,
9... Through hole, 10... Cylindrical plunger.

Claims (1)

[Claims] In an expansion valve that controls the flow rate of fluid by applying a pulse with a constant repetition period to a solenoid valve that operates on and off by pulses, and changing the width of the pulse to change the ON time of the solenoid valve, a flow port is used. A partition wall that partitions the flow port and the valve chamber on one side and a partition wall that partitions the flow port and the other flow port are provided facing each other to form a valve port in one partition wall and a partition wall that is slidable in the other partition wall. A guide hole is formed, and a valve body that opens and closes the valve port is movable in the axial direction at the end of a cylindrical plunger that reciprocates between the electromagnetic attractor and the valve port, and partially protrudes. A spring provided between the valve body and the suction element biases the valve body in the valve closing direction, and a differential pressure eliminating rod having approximately the same diameter as the valve opening can freely slide in the sliding guide hole. The differential pressure eliminating rod is connected to the valve body, and a seal packing provided around the differential pressure eliminating rod is pressurized by a spring so that the pointed end of the seal packing closes the sliding guide hole. An expansion valve for a reversible refrigeration cycle, characterized in that the expansion valve is closed and a passage is formed in the other communication port and the valve chamber.