KR20010043927A - Electrically actuated reed valve - Google Patents

Abstract

An electrically operated valve comprising an inlet 3 and an outlet 4 in the valve housing 2 is provided with a valve lid fixed at one end by a fastener 8 to overcome the pressure and elastic restoring force to close the valve. A simple electromagnetic actuator 1 is used that exerts a force on the piston 6 fitted in the cylinder 5 which raises 7) from the valve mounting surface 9.

Description

ELECTRICALLY ACTUATED REED VALVE

Electromechanical valves are used in a wide variety of fluid and gas flow control applications. Desirable characteristics of such a valve include low leakage, fast response time, low power consumption, long life, low cost, and the ability to open with a high pressure differential across the valve.

The most common type of electromechanical valve according to the prior art is operated by a solenoid. Solenoid-operated valves have a very limited life, very much power can be used, slow response times except for small sizes, and require special configurations to open with high pressure differentials across the valve. The present invention does not have this drawback: it is believed that the present invention uses a small amount of power, responds quickly, easily opens with a high pressure differential across the valve, and is inexpensive and has a practically unlimited lifetime. This allows the present invention to be suitably used in the general field, but in particular as a pulsed expansion valve for refrigeration and air conditioning (US Pat. No. 4,459,819). Pulsed expansion valves must operate reliably for many years, be very inexpensive, be able to open with a pressure differential of at least 300 psi, respond quickly to operating voltages, and have very low leak rates. No electromechanical valve according to the prior art had all these characteristics. For this reason, pulsed expansion valves are not commonly used despite their energy saving advantages. The present invention meets the current, inconsistent conditions for practical pulsed expansion valves.

The present invention relates generally to electromechanical valves. The present invention is particularly suitable for use as pulsed electromechanical expansion valves in refrigerators, heat pumps, or air conditioners.

1A is a cross-sectional view of a basic unidirectional valve in accordance with the present invention in which a wire coil transmitting a magnetically generated current to open the valve is located in the valve chamber and submerged in the fluid or vapor passed by the valve.

1B is a plan view of the valve mounting surface of the embodiment of FIG. 1A.

2A is a cross-sectional view of a preferred embodiment of a unidirectional valve according to the present invention in which a wire coil transmitting a magnetic force generating current to open the valve is located outside the valve chamber.

FIG. 2B is a plan view of the valve mounting surface of the embodiment shown in FIG. 2A.

FIG. 2C is a cross-sectional view of another preferred embodiment of the present invention having a tubular shape such that a coil transmitting current that generates a magnetic force for opening the valve is located outside the valve chamber and the valve chamber itself can be manufactured economically.

Figure 3 shows a bidirectional valve in which the inlets of two unidirectional valves according to the invention are connected by passages.

Figure 4 shows a bidirectional valve in which the outlets of two unidirectional valves according to the invention are connected by passages.

The present invention uses a thin flexible steel reed valve to seal and open a hole in the mounting surface. Unlike the reed valve according to the prior art, which is a manual check valve which is opened by pressure and closed by the elasticity of the reed increased by the back pressure, the reed valve used in the present invention is opened by a simple electromagnetic actuator. The pressure across the valve according to the invention is typically applied in the direction of keeping the valve closed. Thus, such a valve remains closed by the pressure and the elastic force of the lid unless the electromagnetic actuator is actuated, so that the valve is opened by the magnetic force applied on the small ferromagnetic piston. When the actuator is inoperative, the valve closes in response to pressure and the elastic force of the lid itself.

The present invention is a unidirectional valve that allows flow to flow in only one direction. A bidirectional valve, such as a pulsed expansion valve in a heat pump, can be produced by successively connecting two basic valves according to the invention with two outlets or two inlets connected by passages. In the embodiment of the bidirectional valve, the actuator of one of the basic valves is operated to open the valve and the other valve acts as a manual shank valve.

1A and 1B show a basic embodiment of the present invention, in which reference numeral 2 denotes a ferromagnetic passage for magnetic flux. The ferromagnetic passage 2 forms a closed valve chamber axially symmetric about the axis A-A, which has an inlet passage 3 and an outlet passage 4. Unless an energizing voltage is applied to the terminal T connected to the end of the coil 1 by the feedthrough F, the discharge passage 4 is closed by the metal lead 7. When a voltage is applied to the terminal T, current flows in the coil 1 and generates a magnetic field in the ferromagnetic passage 2, which exerts a force on the ferromagnetic piston 6 in the right direction in FIG. 1A. Since the piston 6 is free to move in the cylinder 5, any magnetic force on the piston is applied to the lid 7, which point is then attached to the valve mounting surface 9 by the fastener 8. Bend in the vicinity, thereby releasing the closing of the discharge passage 4. When the activation voltage is removed, the elastic force in the lid 7 straightens the lid so that the discharge passage 4 is closed again.

2a and 2b show a preferred embodiment of the invention in which the coil 1 is located outside the valve chamber. This configuration reduces the cost by eliminating feedthrough (F). The preferred embodiment is also different from the embodiment of FIG. 1 by adding a dummy lead 12 which is activated when the coil 1 is activated with the voltage at the terminal T. By means of 7) an equilibrium torque is applied to the piston 6.

In a preferred embodiment, the valve chamber is formed by a non-ferromagnetic cup 10 having a thin wall, which cup is fixed to the valve mounting surface 9 by a leakproof seal 11 which may be a solder joint or a weld joint. do.

Further, in a preferred embodiment, the ferromagnetic magnetic flow path is a valve 13 and a cylinder 5 in which the ferromagnetic piston 6 can freely reciprocate in the direction of the axis AA, and the portion 13A located completely outside of the valve chamber. It consists of a part 13B including the mounting surface 9. The magnetic flow path 13A need not be axially symmetrical and may be a stack of, for example, E-shaped electrical steel stacks with coils 1 wound around the center leg as shown in FIG. 2A.

Figure 2c shows another preferred embodiment which is economically easy to manufacture. In this embodiment, the valve chamber has a tubular shape and the coil 1 is disposed outside the chamber. Since the ferromagnetic piston 6 is attached to the lid 7 in this embodiment, no dummy lead 12 (see FIGS. 2A and 2B) is required to balance the torque of the piston 6.

If the pressure at the outlet is higher than the pressure at the inlet, none of the above-described basic or preferred embodiments of the invention will work because the valve is opened by the pressure even if no current is applied through the coil 1. will be. Certain applications, such as, for example, pulsed expansion valves for heat pumps, require a bidirectional electromagnetic valve that seals or unblocks the passage and acts despite the high pressure of the end of the passage. 3 and 4 show two ways of implementing the bidirectional valve. Each of these uses two valves according to either of the basic or preferred embodiments described above. In FIG. 3, the outlets of the individual valves VA1, VA2 are connected by passages, and each of the two inlets of the individual valves acts as an inlet or outlet of the bidirectional valve, depending on which is the high pressure. When the valve VA1 is high pressure, the flow from the valve VA1 to the valve VA2 is passed or shut off respectively by activating or deactivating the valve VA2 with the voltage VP, and the valve VA1 is caused by pressure. Open. When the valve VA2 is high pressure, the flow from the valve VA2 to the valve VA1 is controlled by the valve VA1, and the valve VA2 is opened by the high pressure. The DPDT switch 14 applies the activation voltage VP to either the right valve or the left valve depending on whether the high pressure is left or right. In application to heat pump expansion valves, the position of the switch is changed when switching between cooling and heating. The embodiment of the bidirectional valve according to FIG. 4 works similarly to the embodiment of FIG. 3. However, the embodiment of FIG. 4 differs from the embodiment of FIG. 3 in that the individual valves VA3 and VA4 are connected and the inlet / outlet connection of the bidirectional valve is the inlet of the valves VA3 and VA4.

The bidirectional valves of FIGS. 3 and 4 will work while eliminating the cost for switch 15 if the coils of valves VA1 and VA2 are activated simultaneously for either flow direction. This process will only require a small amount of energy to operate a valve that opens spontaneously as a manual check valve, but may be justified by eliminating the potential for cost and reliability degradation associated with the switch 15.

Claims (3)

In the electrically operated valve, a) a valve chamber consisting of a closed volume having an inlet and an outlet and wherein a portion of the interior interface of the volume is a planar valve mounting surface; b) a discharge passage between the inside and the outside of the valve chamber, the discharge passage being an discharge hole formed in the valve mounting surface at an inner end of the discharge passage; c) a flat flexible lead, preferably made of stainless steel, attached to said valve mounting surface at one or more points, said lid being retracted by said lead unless said force is applied to lift said lid from said valve mounting surface; A flexible lead in which the discharge hole is covered and sealed, and d) an electromechanical actuator for opening the outlet aperture by forcing the lid to lift the lid from the valve mounting surface, The electromechanical actuator is, Ferromagnetic paths for magnetic flow with gaps in which all or part of the leads are located, A reset formed on the valve mounting surface and positioned below a portion of the lid located in the gap, A ferromagnetic material located in the reset and freely movable in a direction perpendicular to the valve mounting surface, and And a coil composed of a conductive wire and positioned such that a current flowing through the wire generates a magnetic field in the gap. In a two-way electrically operated valve, A first electrically operated valve according to claim 1 and a second electrically operated valve according to claim 1, wherein an outlet of the first electrically operated valve is connected to an outlet of the second electrically operated valve through a passage. Connected bidirectional electrically actuated valves. In a two-way electrically operated valve, A first electrically operated valve according to claim 1 and a second electrically operated valve according to claim 1, wherein an inlet of the first electrically operated valve is connected to an inlet of the second electrically operated valve through a passage. Connected bidirectional electrically actuated valves.