JPS626148B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an expansion valve device that can change the flow rate of refrigerant, and particularly to one in which the valve opening degree is controlled by a proportional control solenoid.

Conventionally, in a refrigeration cycle, a heat-sensitive tube is installed near the outlet of the evaporator, and this detects the superheated temperature near the outlet of the evaporator, and its output controls an expansion valve device with a poppet valve to change the flow rate of the refrigerant. There is something that lets you do it. However, in such a device, it is not possible to gently change the flow rate of the refrigerant in response to a sudden change in the superheating temperature.

For example, if the expansion valve is to be directly controlled using the temperature information of the location where the temperature is to be controlled, it is desirable to operate the proportional control solenoid based on the temperature information. If the valve is opened and closed, there is a problem in that the control accuracy is not good. Therefore, as in Japanese Patent Application Laid-Open No. 52-106120, a tapered notch groove is provided in the spool so that the opening degree of the valve changes gradually. It may be possible to incorporate what was previously created. However, when changing the flow rate of the refrigerant, unlike in the case of control pressure oil, there is no stroke because the refrigerant leaks from the gap between the outer circumference of the spool and the inner circumference of the cylinder that houses the spool. However, there is a problem in that the flow rate is high. An object of the present invention is to solve these problems and provide an expansion valve device using a proportional control solenoid that can control the flow rate of refrigerant slowly and without leakage.

(Structure) In the expansion valve device of the present invention, a valve seat for a poppet valve that communicates with a refrigerant outlet provided on the front side is provided in the cylinder body of the expansion valve device so that the position can be adjusted, and the refrigerant inlet is located approximately in the center. An opening communicating with is provided. A poppet valve that opens and closes the valve seat for the poppet valve is formed in the front, and a spool that has a tapered notch on the outer periphery of the middle part and forms a sliding valve that opens and closes the opening communicating with the inlet is proportional to the poppet valve. It is connected to a control solenoid and slidably inserted into the cylinder. In the closed position of the poppet valve,
The tapered notch on the outer periphery of the middle part of the spool is
It is provided at a position that does not interfere with the opening communicating with the refrigerant inlet. Further, the compression spring inserted between the front end of the spool and the member provided with the poppet valve seat has a smaller spring force than the compression spring inserted between the rear end of the spool and the proportional control solenoid.

(Operation) The opening degree of the sliding valve changes not suddenly in response to the stroke of the proportional control solenoid, and
Since the poppet valve is always closed when the slide valve is closed, even if refrigerant leaks from the slide valve, there is no leakage of refrigerant from the refrigerant inlet.

Examples will be described in detail below with reference to the drawings.

A... It is a compressor.

B... It is a condenser.

C... Expansion valve device.

D...It is an evaporator. Da is the fluid to be cooled flowing through the evaporator D.

E...A temperature sensor placed in the fluid to be cooled Da, and configured to have a variable set temperature.

The expansion valve device C will be explained below. For convenience of explanation, the left side of the valve device C in FIG. 1 will be referred to as the front, and the right side will be referred to as the rear.

1...A cylindrical body, with a refrigerant inlet 1a and a refrigerant outlet 1
b is open.

2...A cylindrical body inserted into the main body 1, and has a hole 2a communicating with the inlet 1a and a hole 2b communicating with the outlet 1b.

3... A spool that can be slid by a proportional control solenoid 4 (the output of the temperature sensor E is input and the amount of movement is controlled in proportion to it) inserted into the cylinder 2 and attached to the rear end of the main body 1 It is. 3a
is a poppet valve formed at the front end of the spool 3. 3b is a sliding valve that is formed in the middle of the spool 3 and has a tapered notch 3c on a part of its outer periphery. 3d is a passage that communicates the front end side and the rear end side of the spool 3. A member 6 that engages with the rod 4a of the solenoid 4 is integrally fitted into the rear end of the spool 3. A compression spring 7 is provided between the member 6 and the solenoid 4.
is inserted to urge the spool 3 forward. 6a is a passage communicating with the passage 3d.

8: A sliding body slidably inserted into the cylinder 2 in front of the spool 3. 8a is a passage that communicates between the front end side and the rear end side of the sliding body 8, and this passage 8a communicates with the hole 2b.
The rear end of the passage 8a is configured as a valve seat of the poppet valve 3a. Reference numeral 9 denotes a compression spring inserted between the spool 3 and the sliding body 8, and the force of this spring 9 is set smaller than the force of the spring 7.

10...A hollow lid that is fixed to the front end of the main body 1 and closes the front end of the cylindrical body 2. 10a is a female thread provided in the hollow part of the lid 10.

11...A female thread that is screwed together with the female thread 10a, and a ball 12 is inserted between this female thread 11 and the sliding body 8. The position of the sliding body 8 within the cylindrical body 2 can be changed using the male screw 11. Reference numeral 13 denotes a nut that is screwed into the male thread 11, and is configured as a lock nut for the male thread 11.

The poppet valve 3a of the slide valve 3b is connected to the passage 8.
When a is closed, the notch 3c is connected to the hole 2a.
It is located closer to the passage 8a and is designed to close the hole 2a.

Furthermore, the operation of this embodiment will be described.

It is assumed that this refrigeration cycle is now in a stopped state and the expansion valve device C is in a state as shown in FIG.
That is, the valve 3a closes the rear end of the passage 8a, and the valve 3a closes the rear end of the passage 8a.
b is in a state where the hole 2a is closed.

When the compressor A is driven, the spool 3 is first pulled backward by the solenoid 4 so that the opening degree of the valve 3b corresponds to the output of the sensor E corresponding to the temperature of the fluid Da (outside air temperature), and eventually the passage 8a
is open, the hole 2a is in communication with the notch 3c, and the refrigerant is transmitted through the compressor A, the condenser B, the inlet 1a of the expansion valve device C, the hole 2a, the notch 3c, the passage 8a, the hole 2b,
It circulates in the order of outlet 1b and evaporator D.

After a certain period of time, the fluid around sensor E
When the temperature of Da decreases to below the set temperature, the solenoid 4 is controlled by the output of the sensor E, and the spool 3 is slid forward. Then hole 2
The cross-sectional area of the cutout 3c communicating with the cutout 3c decreases, and the flow rate of the refrigerant decreases. Conversely, if the temperature of the fluid Da exceeds the set temperature, the spool 3 is similarly slid backward. Then, the cross-sectional area of the notch 3c that communicates with the hole 2a increases, and the flow rate of the refrigerant increases.
In this way, the temperature of the fluid Da near the sensor E is kept approximately constant.

Note that when sliding the spool 3, since the notch 3c is formed in a tapered shape, even if the position of the spool 3 is changed somewhat roughly, there will be no large change in the cross-sectional area of the notch 3c communicating with the hole 2a. Therefore, the valve opening degree relative to the stroke of the spool can be made gentle without sudden fluctuations.

Note that to first position the rear end of the notch 3c slightly forward of the front end of the hole 2a, loosen the nut 13 and turn the male screw 11 to adjust the position of the slider 8 within the cylinder body 2. Then, the male screw 11 may be locked again with the nut 13 at the desired position.

The above description is only an example, and it goes without saying that the technical scope of the present invention also includes replacement with equivalents of other components.

Since this invention is as described above, it is possible to finely change the refrigerant flow rate passing through the expansion valve device C even if the position of the spool 3 is changed roughly to some extent, and even when the refrigerant flow rate is around zero, it is possible to finely change the refrigerant flow rate. In addition, the expansion valve device can be provided with no leakage of refrigerant.

[Brief explanation of the drawing]

Each of the figures shows an embodiment of the present invention.
The figure is a longitudinal sectional view including the refrigeration cycle, and FIG. 2 is a partial perspective view of the spool. In the figure, C...valve device (expansion valve device), 1...
Cylindrical body, 1a...inlet, 1b...outlet, 2...cylindrical body,
2a, 2b...hole, 3...spool, 3a...poppet valve, 3b...sliding valve, 3c...notch, 4...power device, 8a...passage.

Claims (1)

[Scope of Claims] 1. The poppet valve is provided in a cylindrical body, which is provided with a valve seat for a poppet valve that communicates with a refrigerant outlet provided on the front side, and has an opening that communicates with the refrigerant inlet at approximately the center. A poppet valve for opening and closing a valve seat is formed at the front end, a tapered notch is formed on the outer periphery of the intermediate part, and a spool forming a sliding valve for opening and closing the refrigerant inlet is connected to a proportional control solenoid. the poppet valve is in the closed position, and the tapered notch provided on the outer periphery of the intermediate portion of the spool is set to be located on the side of the opening communicating with the refrigerant inlet. and the compression spring inserted between the front end of the spool and the poppet valve seat has a smaller spring force than the compression spring inserted between the rear end of the spool and the proportional control solenoid.