JPS5881278A - Expansion valve - Google Patents

Abstract

PURPOSE:To pass refrigerant through an expansion valve without flow resistance by providing an orifice and a pass hole on a shaft penetrating through a valve main body. CONSTITUTION:An orifice 25 and a pass hole 26 are provided on the periphery of a shaft lower part 23a in a valve main body 21. When a magnetic force is generated in an electromagnetic coil 29 in the same direction with that of a permanent magnet 28, a plunger 31 is moved greatly to be attracted to an attraction element 30. Then, the pass hole 26 can be kept opened by the work of the permanent magnet 28 and the attraction element 30. As a result, the pass hole 26 considerably greater than the orifice 25 is opened, and refrigerant can pass through with little flow resistance.

Description

[Detailed description of the invention] The present invention is a room air conditioner and a package air conditioner.

This invention relates to an expansion valve that controls the flow rate of refrigerant used in the refrigeration cycle Ic of car air conditioners and pump air conditioners.

As shown in FIG. 1, a typical conventional flow rate control valve is attracted against a plunger 3tl of the valve body 1 and a spring 4 by a magnetic force generated by an electric input signal to an electromagnetic coil 2 attached to the valve body 1. By balancing the attractive force with the spring force of the spring 4, the plunger 3 is held at a position corresponding to the magnitude of the electrical input signal, and the valve element 5 attached to the plunger 3 and the valve body 1 are By electrifying the flow path surface structure of the valve formed by the provided valve seat 6, the valve is configured to continuously control nine valves to flow in accordance with the magnitude of the electrical input signal.

As mentioned above, by the conventional control valve #''!' is supplied to the electromagnetic coil 2, depending on the magnitude of the 61iL air input li.

1! By controlling the flow rate by changing the flow path structure of the valve! However, *Gura/jar 3 made of a magnetic material has a magnetic hysteresis H as shown in Figure 2, so the relationship between input voltage Es and mass t of Gra/jar 3 is as follows: It differs considerably depending on the time C when the voltage Es increases and the time R when it decreases. That is, even if the input voltage Es is the same, the plunger displacement amount is 1. ．． 1. Since it becomes as shown in the figure, a large scale is produced in the flow rate.

Therefore, when this type of flow control valve is put into practical use, equipment for correcting the error must be added, making it very expensive. Also, when this valve is used as a control valve for a heat pump air conditioner, it is used as an expansion valve, but in this case, the flow path area formed between the valve body 5 and the valve seat 6 is very small. This creates a large pressure difference between the spaces 7,8 provided on both sides of the seat 6. For this reason, when the flow direction of the refrigerant is reversed during cooling as in a heat pump air conditioner, the force exerted on the valve body 5 by the pressure difference between the spaces 7 and 8 is in the opposite direction.

Since the balance of forces between the electrode coil 2 and the spring 4 is significantly different during cooling and heating, it is extremely difficult to control the flow rate during both cooling and heating using -1 squares.

Further, as shown in FIG. 3, a typical conventional thermoelectric expansion valve includes a bimetal 11 with a heater 12 wrapped around it inside a container 10 attached to a valve body 9.

The bimetal 11 is deformed by heating the heater 12 by connecting it to a power source (not shown) h via the terminal 11.13b, and the amount of deformation is transferred to the valve body 15 via the spacer
The valve body 9 is configured to control the amount of throttling of the nozzle 16 provided in the valve body 9 by transmitting the signal to the valve body 9 and moving the valve body 9 .

In such a valve, the bimetal 11 is heated by converting an electrical signal into heat by the heater 12.

The heated bimetal 11 is cooled by natural heat dissipation of the fluid in the container 10 to change the amount of deformation of the bimetal 11. Since the electricity g1 is once converted into heat in this way, there is a risk that the response or operation of the valve body 15 will be delayed.

Furthermore, when the above-mentioned valve is used in a heat pump refrigeration cycle, when the refrigerant is flowed in the direction of the arrow 19 during cooling, the high-pressure liquid refrigerant in one opening 17 flows through the nozzle 16, and the low-pressure gas-liquid mixed refrigerant flows through the nozzle 16. and flows to the other opening 18. In this case, the gaseous refrigerant at low pressure enters the container 10 yen through the nozzle 16 tl.

On the other hand, during heating, the refrigerant flows in the opposite direction to that during cooling.
High pressure liquid refrigerant in opening 18 enters container 10 . For this reason, all the heat that attempts to heat the bimetal 11 is taken away by the evaporation of the high-pressure liquid refrigerant, so the bimetal 11
cannot be controlled because it does not deform. As described above, conventional thermoelectric expansion valves have the drawbacks of rapid response and lack of reversible flow.

Furthermore, when the valve shown in FIGS. 1 and 3 is used as an expansion valve in a refrigeration cycle, the cross-sectional area of the flow path at the valve seat 6 and nozzle 16 is set small so that the flow is restricted even when the valve is fully open. There is. The reason is as follows. In other words, if the flow path 117 face area gap is made so large that it is not restricted, the strokes of the valve bodies 5 and 15 must be made large, and therefore the electromagnetic coil 2 and bimetal 11 that move the two square bodies 5 and 15 will also have to be made large. Since the entire valve becomes larger, there are various disadvantages such as an increase in cost, an increase in electrical input, and a decrease in controllability. Therefore, it has been difficult to provide the valve with the ability to allow fluid to flow with almost no fluid resistance, similar to when a general solenoid valve (on-off valve) is opened.

In view of the above, the present invention aims to provide an expansion valve that does not simply perform refrigerant flow rate control 1, but allows refrigerant to flow without flow resistance, has reversible flowability, and has a quick response. A valve body having an opening, one closed hollow shaft that passes through this valve body and is integrally connected to the valve body in a dense layer, and a closed end that is attached to the closed end within this shaft. A circulation space is formed between the shaft in the valve body and the valve body, and this tlt is composed of a permanent magnet and an electromagnetic coil attached to the outer periphery of the closed side of the shaft. 1% mold is caused by the air barrier and the inside of the shaft being delayed by the orifice and the flow port provided in the shaft.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 4, 21 is a valve body having an opening 22;
is a hollow shaft that passes through the valve body 21 and is closely connected to the valve body 21, and a flow space 27 is formed between the shaft 23 and the valve body 21. The shaft 2
3 is closed on one side and has an opening 24 on the other side, and an orifice 25 and a flow port 26 are provided on the peripheral wall of the shaft lower part 23 in the valve body 21.
A permanent magnet 28 and an electromagnetic coil 29 are attached to the outside of the shaft upper part 23b that protrudes upward.

30 is an attractor attached to the closed proximal end within the shaft 23;
Reference numeral 31 denotes a plunger that is slidably provided in the shaft 23 via springs 34 and 35 in the axial direction, and this plunger 31 is provided with a pressure equalizing passage 32 in the axial direction inside, and a pressure equalizing passage 32 is provided in the lower chest wall. a channel 33 is provided radially;
ing.

Next, the operation of this embodiment configured as described above will be explained.

The plunger 31 repeatedly moves up and down due to the balance between the electromagnetic force generated by the electric input signal applied to the electromagnetic coil 29 and the spring force of the springs 34 and 350.
The flow rate per unit time is continuously controlled by opening and closing a good orifice i5 provided at 1. By using a pulse signal as the electrical input signal, the opening degree of the orifice 25 can be controlled by arbitrarily adding up the number of times the plunger 31 opens or closes the orifice 25 or the energization time during which the plunger 3 opens or closes the orifice 25t. can do.

The plunger 31 has pressure equalizing passages 32 in the axial and radial directions.
．． 33, the pressure of the fluid acting on the plunger 31 is always approximately equal to the pressure in the opening 24. In other words, even if a pressure difference occurs between the front and rear of the Oriice 250, this pressure difference has almost no effect on the plunger guard. Then move the refrigerant to shaft 2.
3 through the opening 24, passes through the orifice 25 and the circulation space 27, and enters the valve body j! 1, the pressure at the opening 24 of the shaft 23 becomes p higher than the pressure at the opening 22 of the valve body 21. Further, when the refrigerant is caused to flow in the opposite direction, the pressure in the opening 24 becomes lower than the pressure in the opening 22.

In this way, a pressure difference occurs between the openings 22 and 24 with the orifice 25 as a boundary depending on the flow direction of the refrigerant, but even in such a case, the pressure built around the plunger 31 is always equal to the pressure in the openings 24. equal to and pressure equalization path 33.32
There is almost no pressure difference between the upper and lower surfaces of the passive plunger 31.

Therefore, the electric signal g required to operate the plunger 31t can use the same input signal regardless of the flow direction of the refrigerant, and the flow rate of the refrigerant can be easily controlled regardless of the direction of the refrigerant flow. I can do it.

During cooling operation of the refrigeration cycle, the plunger 31 opens and closes only the orifice 25 and does not open the flow port 26. This is because the stroke of the plunger 31 is determined by the magnitude of the electrical input signal, for example voltage, applied to the 'wL magnetic coil 29, so when only the orifice 25 is opened or closed, the electrical input signal (pulse signal) is applied to the flow outlet. By making the signal smaller than that when 26 is open, the delay can be achieved. Then, on the flow rate side (11), the pulse signal is changed to change the opening/closing time of the orifice 25.

The magnetic force generated by the electromagnetic coil 29 is set in the same direction as the magnetic force of the permanent magnet 28, and a larger electric input signal than that during flow rate control is applied to move the plunger 31 largely to cause the attractor 30 to pull. When the input of the electric signal to the electromagnetic coil 29 is interrupted after this suction is completed, the flow port 'zeyP can be maintained in the open state by the l1ll movement of the permanent magnet 28 and the attractor 30.

In this way, the flow port 26, which is larger than the orifice 25, is opened, so that the refrigerant can flow with almost no resistance. On the other hand, when the flow port 26 is closed.

Conversely, if an electrical input signal is applied to the electromagnetic coil 29 so as to generate a magnetic force in the opposite direction to the magnetic force of the permanent magnet 28, the ff port 26 is closed and the refrigerant flow rate is returned to a state controlled.

In this embodiment described above, the plunger 31 is provided with a pressure equalizing passage 32 .
38, but when the plunger 31 has a small diameter and a pressure equalizing path cannot be provided.

The pressure in the opening 24 of the shaft 23 may be guided to the opposite side of the plunger 310 (on the upper surface side) by an external pressure equalizing pipe. Further, in this embodiment, the orifice 25 and the flow port 26 are separately provided at the lower part of the shaft 23 to facilitate control, but when the magnitude of the electrical input signal to the electromagnetic coil 29 can be precisely controlled, 26 may be combined into one, and the stroke of the cipher/jar 31 may be controlled depending on the magnitude of the electrical input signal.

As explained above, according to the present invention, by providing an oriice and a flow port in the shaft, it is possible not only to control the flow rate of the refrigerant but also to flow the refrigerant without flow resistance.
In addition, regardless of the flow direction of the refrigerant, reversible flowability is achieved by easily controlling the flow rate of the refrigerant, making it possible to control the refrigerant and heating operations with a single valve. can. Furthermore, by directly moving the plunger as magnetic force without converting the electrical input signal to the electromagnetic coil into heat, response can be made faster, improving the start-up performance of the refrigerator. It is. Furthermore, since the flow port of the shaft can be kept open by the action of the permanent magnet and the attractor, it is possible to save electric power and improve economic efficiency.

[Brief explanation of the drawing]

Figure 1 is a sectional view of a conventional control valve, Figure 2 is an explanatory diagram of the production of the same control valve, and Figure 3 is a sectional view of a conventional thermoelectric expansion valve.
The figure is a sectional view showing an embodiment of the expansion valve of the present invention. 21...Valve body, 22.24...Opening, 23...
Hollow shaft, 25...orifice, 26...flow port. 27... Distribution intermediate, 28... Permanent magnet, 29...
Electromagnetic coil, 30... Attractor, 31... Plunger, 32° 33... Pressure equalization path.゛Representative Patent Attorney Shizuku Hakata 1 Figure 7 Figure included t H-(E<:) r"Figure 3/'?)

Claims (1)

[Scope of Claims] 1. A valve body having an opening, a hollow shaft extending back from this valve body and integrally connected to the valve body, and one of which is closed, and a blockage in this shaft. A 9.degree. An expansion valve characterized in that a flow space is formed between a shaft within the valve body and the valve body, and the flow space and the inside of the shaft are communicated with an oriice provided in the shaft through a flow port. 2. Claim 1, characterized in that the plunger is provided with pressure equalizing passages in the 1 km direction and in the radial direction, respectively.
Expansion valve as described in section.