JPS61236981A - Four-way reversing valve for reversible refrigerating cycle - Google Patents

Abstract

PURPOSE:To provide a four-way reversing valve for reversible refrigerating cycle which may be quickly switched from a heating operation to a cooling operation, by providing an auxiliary return spring operable in the heating operation only. CONSTITUTION:When a solenoid valve 16 is energized and a compressor 4 is started in a cooling operation, a plunger 17 is attracted, and a needle valve 18 opens a pressure relief hole 3a to communicate a pressure converting chamber R2 with a low-pressure suction side of the compressor 4. As a result, the pressure in the pressure converting chamber R2 is reduced, and therefore, there is generated a pressure differential greater than a resilient force of a compression spring 13 between chambers R1 and R2, thereby starting to move a piston 12 and a slide valve 21 toward a plug 3. Accordingly, an auxiliary return spring 12g is compressed to close a pressure balancing hole 12a, then stopping the cooling operation and being switched to a heating operation. In the heating operation, when the compressor 4 is stopped by a thermostat, pressure on the high pressure side and that on the low pressure side are gradually balanced to reach a maximum operational pressure differential. Then, the piston starts to be moved relatively quickly by resilient forces of the compression spring 13 and the auxiliary return spring 12g. Thus, the heating operation is switched to a cooling operation.

Description

[Detailed Description of the Invention] [Object of the Invention] Arashi Presentation ■Saradoko! The present invention relates to a four-way reversing valve used for switching between cooling and heating in a dual-purpose air conditioner.

Part U: Conventional differential pressure-driven four-way reversing valves use a pair of pistons, etc. within the cylindrical reversing valve body to convert between a high pressure chamber, a low pressure chamber, and a pressure conversion chamber, or between a high pressure chamber and two pressure conversion chambers. In most cases, the pressure converting chamber is divided into three chambers, and the pressure converting chamber is switched by a pilot three-way solenoid valve, etc., and a piston or a valve body connected to the piston is moved. Ta.

In the above-mentioned conventional technology, both the reversing four-way valve and the pyro-magnetic valve have complex structures and a large number of mutually communicating conduits, which is an obstacle to miniaturization. Control by operating a pilot electromagnetic valve involves scouting for pressure reduction and active pressurization of the pressure conversion chamber, which has disadvantages such as being unsuitable for fine electronic control.

The present invention focuses on the above-mentioned points, and divides the inside of the reversing valve body into two parts, a high pressure chamber and a pressure conversion chamber, by a piston, and opens and closes the pressure conversion chamber by an on-off valve, and uses differential pressure or a spring to separate the piston or the pressure conversion chamber. adopts a configuration in which the flow path switching valve is moved, thereby achieving a simpler and more compact structure, and controlling the pressure conversion★ by the on-off valve from the pressure conversion chamber to the suction side of the compressor. The knobs that open and close the refrigerant flow enable fine control by electronic system, and furthermore, the switching from heating operation to cooling operation can be speeded up by moving the piston or flow path switching valve using a spring.

[Structure of the invention]

. In order to achieve the above-mentioned object of controlling the air pressure, the present invention divides the inside of the cylindrical reversing valve body into a high pressure chamber and a pressure conversion chamber by means of a piston, and the high pressure chamber is provided with a connection port for the discharge pipe of the compressor and a pressure conversion chamber. ,
Connecting port to the suction pipe of the compressor and holding the connecting port 2
A series of switching valve seats are provided from the connection ports for the suction pipes to the connection ports for the two heat exchanger pipes, and a slide valve is provided in sliding contact with the switching valve seats. A pressure equalizing hole is connected to the piston and communicates between the high pressure chamber and the pressure conversion chamber in the piston. At the same time, a pressure equalizing hole is formed in the pressure equalizing hole during heating operation to block the flow to the high pressure chamber or the pressure conversion chamber. A spring that always biases the piston toward the high pressure chamber and an auxiliary spring that biases the piston toward the high pressure chamber only during heating operation are provided, and the pressure conversion chamber is connected to the suction side of the compressor. A configuration was adopted in which a communicating pressure relief hole was provided, an on-off valve was provided in the pressure relief hole, and the diameter of the pressure relief hole was made larger than the diameter of the pressure equalization hole.

Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings. In the drawings, reference numeral 1 denotes a cylindrical reversing valve body, and plugs 2 and 3 are welded and fixed to both ends. A discharge pipe 5 of the compressor 4 is connected to the plug body 2, and two conduits 7, 114 are connected to the reversing valve body 1 with the suction pipe 6 of the compressor 4 sandwiched between them in the axial direction. The conduits 7, 8 are connected to two heat exchangers 9, 10 which are used reciprocally as condensers or evaporators. The inner ends of the suction pipe 6 and conduits 7 and 8 are connected to the reversing valve body 1.
Three through holes 11 of the switching valve seat 11 fixed inside.
asllbtllc, and a series of smooth surfaces lid are formed inside the valve seat 11.

Inside the reversing valve body 1, a piston 12 frame (slidably provided between the valve seat 11 and the plug body 3 divides the inside of the reversing valve body 1 into a high pressure chamber R1 and a pressure conversion chamber R2. The piston 12 and the plug body A compression spring 13 is provided between the piston 12 and the high pressure chamber R, and the piston 12 is always biased in the force direction. The pressure equalizing hole 12 is formed in the plug body 3.
A pressure relief hole 3a having a larger diameter than the pressure relief hole 3a is formed, and a conduit 14 leading to the suction pipe 6 is connected to the pressure relief hole 3a. A valve seat 12b and a valve chamber 12c are provided at the end of the pressure conversion chamber side of the pressure equalization hole 12a, and a ball-shaped valve body 12d is disposed within the valve chamber 12c. A ring-shaped abutment 12f is slidably mounted on a pedestal, and the four abutments 12f are also located outside H.
jl12e is biased to protrude in the direction of the stopper 3 by a return auxiliary compression spring 12g wound around the abutment 12. The ball-shaped valve body 1 is opened by the opening 12f of f.
2d is supported in a partially protruding state.

Pline 4 on the plug body 3. Electromagnetic on-off valve 16 via Yapipe 15
5 is attached, and a ball valve 18 provided at the tip of the plunger 17 is provided in the middle of the pressure relief hole 3a) 3
b to open and close the pressure relief hole 3a. Immediately, the pressure relief hole 3a is connected to the pressure conversion chamber R at the outer peripheral portion of the plug body 3.
The valve chamber 3c side of the through hole 3a is composed of a through hole 3a4 reaching the valve chamber 3C from the valve chamber 3C, and a radial through hole 3a from the through hole 3az passing through the center part of the plug body 3 from the valve chamber 3C. A valve seat 3b is provided at the end, and the conduit 14 is connected to the through hole 3a. A compression spring 20 is provided between the plunger 17 and the suction core 19, and the ball valve 18 is biased in the direction of contacting the valve seat 3b.

A slide valve 21 having a communication bore 21a is provided on the valve seat 11, and the slide valve 21 is connected to the piston 12 by a connecting rod 22. The slide valve 21 moves to the valve seat 11 through its inner cavity 21a.
The through hole 11a for the suction pipe 6 is alternatively communicated with the through hole 11bsllc for the heat exchanger conduit 7.8 on both sides thereof.

In the above configuration, FIG. 1 shows the cooling operation state, that is, the electromagnetic on-off valve 16 is in a non-energized state and the plunger 17 is in a plunging state.
is pushed by the spring 20 and the ball valve 18 closes to the pressure relief hole 3.
a is closed, the high pressure chamber R and the pressure conversion chamber R3 have the same pressure due to the pressure equalization hole 12a, and therefore the piston 12 is pushed by the spring 13 until it comes into contact with the valve seat 11.
Since the slide valve 21 allows the through hole 11a to communicate with the through hole 11c, the refrigerant flows through the compressor 4 - the discharge pipe 5 - the alt pipe 7 - the outdoor heat exchanger 9 - the throttle means 23 - the indoor heat exchanger 10
It circulates along the route of - conduit 8 -> suction pipe 6 - compressor 4.

Next, when the electromagnetic on-off valve 16 is energized and the compressor 4 is started, the plunger 17 is attracted, the needle valve body 18 opens the pressure relief hole 3a, and the inside of the pressure conversion chamber R2 is changed to the low pressure on the suction side of the compressor 4. communicate.

As a result, in the pressure conversion chamber R2, the refrigerant escapes from the pressure relief hole 3a to the suction side, and at the same time, the refrigerant is supplied from the high pressure chamber R+ through the pressure equalization hole 12a, and at this time, the diameter of the pressure relief hole 3a becomes equal to the pressure. Since the diameter of the hole 12a is larger and the amount of refrigerant discharged is larger than the amount of refrigerant supplied, the pressure conversion chamber R2 becomes low pressure, and a pressure difference that overcomes the elasticity of the compression spring 13 is generated between the chambers R1 and R1. As shown in FIG. 2, the piston 12 to the slide valve 21 start moving in the direction of the stopper 3.

When the piston 12 approaches the stopper 3 due to the above movement,
The valve body 12d to the abutment 12f come into contact with the stopper 3, compressing the return auxiliary spring 12g, and stop with the valve body 12d coming into contact with the valve seat 12b and closing the pressure equalizing hole 12a! , in this state, the slide valve 21 opens through hole 1.
Since the through hole 1a is communicated with the through hole 11b, the refrigerant is circulated through the route of the compressor 4, the outlet pipe 5, the conduit 8, the outdoor heat exchanger 10, the throttle means 2, and 4, resulting in heating operation.

During heating operation, when the compressor 4 is stopped by the thermostat, the high pressure and low pressure sides gradually become balanced, and when the maximum operating pressure difference is reached, the piston is moved by the elastic force of the first compression spring 13 and the auxiliary compression spring 12g. Start moving relatively quickly.

In this way, during the heating operation, after quickly switching to the cooling state, the defrosting operation is performed in response to the defrosting start signal.

In the embodiment shown in FIG. 4, the piston 1 is
A needle-shaped valve body 12d' facing the pressure equalizing hole 12a of No. 2
is provided, and when the piston 12 approaches the stopper 3, the needle-shaped valve element 12d' comes into contact with the valve seat 12b and closes. Further, in place of the abutment 12f, a protrusion 12f' that compresses the auxiliary spring 12g against the plug body 3 is provided.

〔Effect of the invention〕

As described above, the present invention divides the interior of a cylindrical reversing valve into a high pressure chamber and a pressure conversion chamber by means of a piston, and the high pressure chamber has a connection port for the discharge pipe of the compressor and a connection port for the suction pipe of the compressor. A series of switching valve seats are provided from the connection port for the suction pipe to the connection ports for the two heat exchanger conduits. A slide valve that is in sliding contact with the switching valve seat is connected to the piston, and a pressure equalization hole is formed in the piston to communicate the high pressure chamber and the pressure conversion chamber. A valve body is provided to shut off the flow from the air to the pressure conversion chamber, and a spring that constantly biases the piston toward the high pressure chamber and an auxiliary spring that biases the piston toward the high pressure chamber only during heating operation are provided. A pressure relief hole communicating with the suction side of the compressor is provided in the chamber, an on-off valve is provided in the pressure relief hole, and the diameter of the pressure relief hole is formed to be larger than the diameter of the pressure equalization hole.
The structure can be greatly simplified, operation can be stabilized, miniaturization can be achieved, and fine control can be performed by electronic means.

In particular, in the present invention, since an auxiliary return spring is provided that operates only during heating operation, it is possible to speed up the switching from heating operation to cooling operation, and also to speed up the switching from cooling operation to heating operation. Since the pressure equalizing hole is immediately closed by the valve body when the cooling operation shifts to the heating operation, leakage of refrigerant can be minimized.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the cooling operation state of an embodiment of the present invention, Fig. 2 is an operation state diagram during the transition from cooling operation to heating operation in the same example, and Fig. 3 shows the heating operation state in the same example. The sectional view, FIG. 4, is a detailed view of another embodiment of the valve body. 1...Reversing valve body, R+...High pressure chamber, R2...Pressure conversion chamber, 4...Compressor, 5...Discharge pipe, 6...
Suction pipe, 9.10...Heat exchanger, 11...Switching valve seat, 12...Piston, 12a...Pressure equalization hole, 3a...Pressure relief hole, 12d... Valve body, 12g・
...Auxiliary spring, 13...Compression spring, 18.''Opening/closing valve.

Claims (1)

[Claims] The cylindrical reversing valve body is divided into a high pressure chamber and a pressure conversion chamber by a piston, and the high pressure chamber has a connection port for the discharge pipe of the compressor, a connection port for the suction pipe of the compressor, and two ports sandwiching the connection port. and a connection port for the heat exchanger conduit,
A series of switching valve seats is provided from the connection port for the suction pipe to the connection port for the two heat exchanger conduits, and a slide valve in sliding contact with the switching valve seat is connected to the piston. A pressure equalization hole is formed that communicates the conversion chamber, and a valve body is provided in the pressure equalization hole to block the flow from the high pressure chamber to the pressure conversion chamber during heating operation, and a spring that constantly biases the piston in the direction of the high pressure chamber. and an auxiliary spring that biases the piston toward the high pressure chamber only during heating operation, a pressure relief hole communicating with the suction side of the compressor is provided in the pressure conversion chamber, and an on-off valve is provided in the pressure relief hole. A four-way reversing valve for a reversible refrigeration cycle, characterized in that the diameter of the pressure relief hole is larger than the diameter of the pressure equalization hole.