JPS62266369A - Expansion valve - 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] [Industrial Application Field] The present invention relates to an expansion valve that expands high-pressure fluid to low-pressure fluid, and is used as a refrigerant expansion valve in the refrigeration cycle of an air conditioner such as a car air conditioner. It is something that can be done.

[Conventional technology]

This type of expansion valve communicates with an inlet side that receives high-pressure fluid, that is, a high-pressure passage, and a downstream end of this high-pressure side passage, as shown in FIGS. 11 and 12 of Japanese Patent Publication No. 53-45539, for example. an orifice arranged to restrict the flow of high-pressure fluid; a valve member arranged to be movable forward and backward with respect to the orifice to adjust 2tffi passing through the orifice; and a valve member arranged in communication with the downstream end of the orifice. and an outlet side, that is, a low pressure side passage.

[Problem that the invention seeks to solve]

Is the pressure on the downstream side of the expansion valve the same as above? The lower the setting pressure is, the narrower the gap between the valve member and the inner circumferential surface of the valve seat or the valve seat.
When this happens, a contraction occurs in the flow, increasing the flow velocity and decreasing the pressure, causing the water contained in the fluid to freeze on the valve and block the gap, so-called "icing". "phenomenon" is likely to occur. When this phenomenon occurs, the outlet passage of the expansion valve becomes under negative pressure, and the refrigerant does not flow, causing problems such as abnormal overheating of the compressor and poor cooling, so it is necessary to prevent this icing phenomenon.

[Means for solving problems]

The present invention applies rotational force to the valve member by the flow of fluid.
t:N is formed on the valve member itself.

[Effect]

Since the valve member is rotationally driven by the flow of fluid within the expansion valve, the valve member rotates relative to the inner circumferential surface of the orifice or the valve seat, which prevents water contained in the fluid from freezing. Therefore, no icing phenomenon occurs even if the set pressure of the expansion valve is very low.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention shown in the drawings will be described. First, a general car air conditioner refrigeration cycle in which a refrigerant expansion valve is used will be briefly described with reference to FIG. The refrigeration cycle has a compressor 1, and the refrigerant sucked into the compressor 1 as a gas is compressed by the compressor 1, and sent through a pipe 2 to a condenser 3, where it is compressed by air sent from a fan 3a. It is cooled and condensed to become a liquid refrigerant. This liquid refrigerant is sent through line 4 to receiver 5, where it is stored as a liquid at low pressure. The high-pressure refrigerant liquid then passes through the high-pressure side pipe 6 and enters the expansion valve 7, and the refrigerant that has expanded after passing through the expansion valve 7 passes through the low-pressure side pipe 3 in a liquid phase with some gas phase mixed in. The air then flows into the air generator 9, where it absorbs heat from the air sent from air 9a and evaporates into an almost complete gas, returns to the compressor 1 through the pipe 10, and in this way the refrigeration cycle is performed. . The expansion valve 7 opens when the downstream pressure drops to the set pressure, and functions to maintain the downstream pressure at the set pressure. In FIG. 2, reference numeral 11 is a temperature-sensitive tube, and reference numeral 12 is an electromagnetic clutch that connects and disconnects power transmission between the compressor 11 and the automobile engine.

Next, the detailed structure of the expansion valve 7 according to an embodiment of the present invention will be described. The expansion valve, indicated as a whole by 7 in FIG. 1, includes a valve body 13 made of metal such as copper, an inlet side passage provided in this valve body 13, that is, a high pressure side refrigerant passage 14, and this passage. The high pressure side refrigerant passage 14 has a large diameter section 16 and a downstream end of the large diameter section 16. The large diameter portion 16 is connected to the high pressure side pipe line 6 shown in FIG.
The low pressure side refrigerant passage 15 is connected to the low two pressure side passage 8 shown in FIG. An orifice 18 is further provided in the valve body 13 and has an axis perpendicular to the longitudinal axis of the high-pressure side refrigerant passage 14 and is arranged concentrically with respect to the low-pressure side refrigerant passage 15. 18 has an upstream end that opens to the small diameter portion 17 of the high-pressure side refrigerant passage 14 and a downstream end that opens to the low-pressure side refrigerant passage 15, and allows the passages 14 and 15 to communicate with each other. A valve seat 19 is provided at the downstream end of the orifice 18 and is continuous with the inner peripheral surface of the orifice 18, and a spherical valve member 20 disposed within the low pressure side refrigerant passage 15 is associated with the valve seat 19. There is. The valve member 20 is made of metal such as stainless steel, and the outer peripheral surface of the spherical valve member 20 is provided with vanes 21 that are driven by the energy of the flow of refrigerant through the orifice 18 to rotate the valve member 20. Figure 3 (al, (b) and Figure 4 (a),
(bl is a diagram showing details of the spherical valve member 20,
FIG. 3 (al is an external view, FIG. 3(b) is a top view, and FIG. 4(a) is a top view.

(b) is a cross-sectional view of each spring seat 22 made of brass or the like.
and the support rod 23 are integrally connected, and the upper part of the support rod 23 holds a plurality of stainless steel balls 24. This ball 24 contacts a groove 25 provided on the inner surface of the spherical valve member 20 to smoothly rotate the valve member 20, and also connects the valve member 20 and the support rod 23 to the concave portion of the support rod 23. It is composed of a combination of

Referring again to FIG. 1, the spring seat 22 and, by extension, the valve member 20 are compressed by a compressor interposed between the annular NAND member 26 made of metal such as copper and screwed into the low pressure side refrigerant passage 15. It is spring-loaded in the direction of the valve seat 19 by a coil spring 27 . The pressing force of the spring 27 against the valve member 20 is adjusted by changing the position of the NAND member 26. The opening direction of the valve member 20 is the same as the flow direction of the high pressure refrigerant flowing through the orifice 18. A recess is formed in the upper surface of the valve body 13 as seen in FIG.
A metal diaphragm 3 is placed within this space 29.
0 is provided to divide this space 29 into two chambers 31 and 32. One chamber 31 receives m pressure signals from the thermosensor tube 11 through a conduit 33 shown in FIG. 2 attached to the cover member 28.5. The other chamber 32 is communicated with the low-pressure refrigerant passage 15 through a passage 34 provided in the valve body 13 so that the pressure in the low-pressure refrigerant passage, that is, the evaporation pressure, is introduced into the chamber 32. It has become. A contact member 35 that is in contact with the diaphragm 30 is provided in the chamber 32, and the contact member 35
bears four legs 36 (only two of which are shown in FIG. 1). The legs 36 are slidably fitted into holes provided in the valve body 13, and the lower ends of the legs 36 are brought into contact with the top surface of the spring seat 22. The temperature sensing cylinder 11 emits a pressure signal corresponding to the refrigerant temperature at the inlet side of the compressor 1, and the pressure signal enters one chamber 31 through a dedicated pipe 33 and is transmitted to the diaphragm 3.
It acts on one surface (top surface) of 0. Moreover, the pressure in the low pressure side refrigerant passage 15 acts on the other surface (lower surface) of the diaphragm 30 via the passage 34, and therefore, the diaphragm 30 is Displaced to. This displacement of the diaphragm 30 is transmitted to the spring seat 22 via the abutment member 35 and the leg 36 in contact with it, and the position of the valve member 20 relative to the valve seat 19 is adjusted. The gap between the valve seat 19 and the valve member 20 is thus adjusted, thereby controlling the flow rate of refrigerant through the orifice 18.

Next, the operation of the above embodiment will be explained with reference to FIGS. 1 and 2. When the temperature sensing cylinder 11 senses an increase in refrigerant temperature on the inlet side of the compressor 1, a corresponding pressure signal is sent to the conduit 3.
3 into the chamber 31 of the expansion valve 7 and displaces the diaphragm 30 in a direction approaching the valve body 13 against the force of the spring 27. , the valve member 20 is moved away from the orifice 18, thereby increasing the gap between the valve member 20 and the valve seat 19 and increasing the flow rate of refrigerant through the orifice 18. Conversely, when the thermosensor cylinder 11 senses the pressure plus a decrease in refrigerant temperature on the iMat inlet side, a corresponding pressure signal flows into the chamber 31 and displaces the diaphragm 30 in the direction away from the valve body 13. , whereby spring seat 22 is moved by spring 27 in a direction closer to orifice 18 to reduce the gap between valve member 20 and valve seat 19, thereby reducing the flow rate of refrigerant through orifice 18. When the refrigerant passes through the narrow gap between the valve seat 19 and the valve member 20, its flow velocity increases rapidly, which applies rotational force to the vanes 21 formed on the outer periphery of the spherical valve member 20. Valve member 20 rotates. Thereby, the icing phenomenon (a phenomenon in which water in the refrigerant freezes on the valve member and cools the flow path) can be avoided.

Next, modified embodiments of the valve member portion of the expansion valve according to the present invention will be described. In the embodiment shown in FIGS. 5 fal and 5 fbl, the valve member 20 has a conical shape,
The other configurations are the same as the embodiments shown in FIGS. 3 (al, Fbl) and FIGS. In the example, the blades 21 are provided protruding from the surface of the valve part vr20, whereas the valve member itself is provided by cutting G.
The effect is the same. In the actual example shown in FIG. 7, the hole 24 in the embodiment shown in FIGS. 4(a) and 4(b). i'+! Even if i25 is incorporated into the spring seat 22, the effect is the same.

〔Effect of the invention〕

In the expansion valve according to the present invention, the mechanism (vanes 21) that applies rotational force to the valve member by the flow of fluid is formed in the valve member itself, so that the valve member rotates with respect to the valve seat, and the valve member and valve This has the effect of preventing moisture in the fluid from freezing between the seat and the seat. Another advantage is that other parts such as an impeller are not required.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing the configuration of an embodiment of the expansion valve according to the present invention, FIG. 2 is a diagram showing the circuit configuration of a refrigeration cycle for a car air conditioner using the expansion valve shown in FIG. 1, 3 (fan, fb) and 4 (al, (b)) are views showing details of the valve member portion of the expansion valve of the present invention shown in FIG. 1, and FIG. 3 (fa) is an external view; (b) is a top view, the fourth
Figures (a) and (b) are respective sectional views, and Figure 5 (a). (b), Fig. 6 (al), (b) and Fig. 7 are views showing details of other embodiments of the valve member portion in the expansion valve of the present invention shown in Fig. 1. 1... Compressor , 3... Condenser, 5... Liquid receiver, 7
...expansion valve, 9...evaporator, 11...thermal tube, 1
2... Electromagnetic clutch, 13... Valve body, 14...
Inlet side (high pressure side) refrigerant passage, 15... Outlet side (low pressure side) refrigerant passage, 18... Orifice, 19... Valve seat,
20... Valve member, 21... Vane, 22... Wing seat, 23... Valve support, 24... Ball, 25...
Groove, 26... Throat member, 27... Spring, 30...
...Diaphragm, 34...Passage, 35...Attaching member, 36...Legs.

Claims (1)

[Claims] an inlet refrigerant passage for receiving high-pressure fluid; an orifice disposed in communication with the downstream end of the inlet refrigerant passage to throttle the flow of the high-pressure fluid; In an expansion valve that includes a valve member that is arranged to move forward and backward, and an outlet side refrigerant passage that is arranged in communication with the downstream end of the orifice, the valve member is rotatably supported and the valve is expanded by the flow of fluid. An expansion valve characterized in that a mechanism for applying rotational force to the member is formed in the valve member itself.