JP2004084885A - Solenoid valve and its assembling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solenoid valve for reducing reduction in strength, and preventing reduction in magnetic force and an increase in electric power consumption. <P>SOLUTION: This solenoid valve opens-closes a passage of fluid, and has a valve body 1 connected with inlet side and outlet side joints 2 and 3 of the fluid, a valve element 9 for opening-closing the passage by a valve seat 5 formed in the valve body 1, a plunger 8 for operating the valve element 9, a plunger tube 7 for slidingly inserting the plunger 8 and an electromagnetic coil member detachably installed outside the plunger tube 7, and is constituted so that the valve body 1 is formed of stainless steel, the plunger tube 7 is formed of stainless steel, and the joints 2 and 3 are formed of copper or stainless steel. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electromagnetic valve used for controlling a refrigerant liquid and a gas in a refrigeration / cooling circuit, and particularly to an electromagnetic valve used for opening / closing a refrigerant flow path of an air conditioner using an ultra-high pressure refrigerant such as CO ₂ and a hot water supply device, and assembly thereof. It is about the method.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a refrigerating / refrigerating / air-conditioning cycle of a heat pump type air conditioner, a refrigerator, a refrigerator, or the like, an electromagnetic valve is incorporated in a refrigerant flow path for controlling a flow rate of a refrigerant or switching a flow path.
[0003]
As a known example of such a solenoid valve, there is a two-way solenoid valve having a structure shown in FIG.
In addition, in addition to the two-way solenoid valve, there is a three-way solenoid valve, a four-way solenoid valve, and other solenoid valves having a plurality of flow path switching, and the same description is given for these solenoid valves.
That is, the first copper joint 02 and the second copper joint 03 are hermetically joined to the brass valve body 01 by brazing R. A valve seat 05 is provided in a valve chamber 04 in the valve body 01, and a valve hole 06 is inserted between the valve seat 05 and the second copper joint 03. A stainless steel plunger tube 07 is fixed to the brass valve body 01 upright by brazing R. A spherical valve body 09 is held at the tip of a plunger 08 slidably provided in the plunger tube 07, and the valve seat 05 and the spherical valve body 09 can be freely contacted and separated by the vertical movement of the plunger 08.
[0004]
A suction element 010 inserted into the plunger tube 07 is fitted to the upper end of the plunger 08, and the suction element 010 is welded to the upper end 07a of the plunger tube 07 by welding. A spring 014 is arranged in a compressed state between the lower end surface 011 of the suction element 010 and the concave portion 013 of the upper end surface 012 of the plunger 08. An annular groove 015 is provided in the lower end surface 011 of the suction element 010, and an annular shading coil 016 is fitted and fixed in the annular groove 015. A screw hole 017 is provided at the upper part of the suction element 010. After an electromagnetic coil member (not shown) is fixed to the valve body 01 around the plunger tube 07, a screw penetrating a case covering the periphery is inserted into the screw hole 017. It is fixed by screwing.
[0005]
In the operation of the solenoid valve, when a coil (not shown) is not energized, the plunger 08 is pressed downward together with the spherical valve body 09 by the spring 014 as shown in FIG. 2 to close the valve hole 06. When the coil is energized from this state, the attraction element 010 is excited, attracts the plunger 08 against the spring 014, and stops by bringing the upper end face 012 of the plunger 08 into contact with the lower end face 011 of the attraction element 010. Keep state. That is, the plunger 08 compresses the spring 014 and adsorbs on the suction element 010, so that the spherical valve body 09 attached to the plunger 08 and the valve seat 05 provided on the brass valve body 01 are separated from each other, and the fluid is made of the first copper joint 02 and the copper. It passes between the second joint 03. Next, when the energization of the coil is stopped, the suction force of the suction element 010 is lost, the plunger 08 is lowered by the spring 014, and the spherical valve body 09 and the valve seat 05 provided on the brass valve main body 01 are sealed to form a brass second valve. The fluid flow between the first joint 02 and the brass second joint 03 stops.
[0006]
[Problems to be solved by the invention]
In the conventional solenoid valve as described above, brass is used for the valve body 01 for maintaining airtightness, and copper first and second joints 02 and 03 for connecting the brass valve body 01 to the refrigeration cycle system. Is attached to the brass valve body 01 by brazing R using a flux. Also, brazing R using a flux is performed to hermetically join the brass valve body 01 and the stainless steel plunger tube 07. For this reason, the plunger tube 07 becomes dull due to exposure to heat, and the strength is reduced.
[0007]
Further, when the plunger tube 07 and the valve body 01 are joined by brazing in the furnace R, the plunger tube 07 made of stainless steel is further exposed to high heat and becomes dull, and the strength is reduced. In particular, if the valve body is made of stainless steel, brazing in a furnace R using no flux generally requires brazing at 1000 ° C. or higher, which further reduces the strength.
[0008]
In particular, when a high-pressure refrigerant such as CO2 is used, an electromagnetic valve having an increased thickness of the plunger tube as shown in FIG. 3 must be used.
[0009]
Here, the solenoid valve shown in FIG. 3 is essentially the same as the solenoid valve shown in FIG. 2, so that the description of the same structure will be omitted, and only the differences will be described. 020, and the valve body receiver 021 is housed in the valve body 01 between the second joint 03 and the holder 020. A valve seat 05 is formed at the upper end of the valve body receiver 21. Further, an equalizing path 022 communicating from the concave portion 013 of the plunger 08 to the spherical valve element 09 is formed along the axis of the plunger, and a valve element spring 024 is accommodated in an enlarged portion 023 of the plunger 08. The valve body 09 is biased.
[0010]
As described above, since the solenoid valve using a high-pressure refrigerant such as CO2 requires an increase in the thickness of the plunger tube in order to oppose the high-pressure refrigerant, the magnetic force decreases and power consumption increases accordingly. Occurs.
The present invention solves the problem by providing a solenoid valve that reduces a decrease in strength and prevents a decrease in magnetic force and an increase in power consumption.
[0011]
[Means for Solving the Problems]
The present invention relates to an electromagnetic valve that opens and closes a fluid flow path, wherein the flow path is opened and closed by a valve body to which a fluid inlet side and an outlet side joint are connected, and a valve seat formed in the valve body. A valve body, a plunger for operating the valve body, a plunger tube into which the plunger is slidably inserted, and an electromagnetic coil member detachably attached to the outside of the plunger tube, wherein the valve body is made of stainless steel. An electromagnetic valve in which the plunger tube is made of stainless steel and the joint is made of copper or stainless steel, and a stainless steel valve body and a joint on the inlet side and outlet side of a fluid attached to the valve body. After airtightly joined by brazing in an atmosphere furnace, the valve body and the stainless steel plunger tube are welded and airtightly joined by welding. That.
[0012]
In this way, the plunger tubes can be joined without dulling them, and the plunger tubes can be made thinner even when a high-pressure refrigerant is used. In addition, the stainless steel plunger tube and the valve body are integrated by welding while maintaining the airtightness and the flow path securing function of the brass body of the solenoid valve, and the joint is airtight by fluxless brazing. Is held.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a cross section of the solenoid valve. A copper or stainless steel first joint 2 and a copper or stainless steel second joint 3 are hermetically joined to a stainless steel valve body 1 by brazing R.
[0014]
Nickel brazing (paste) or copper brazing (ring) is generally used as the brazing material. Phosphor bronze (ring) is used for the solenoid valve of the present invention in terms of workability and cost. Is preferred.
[0015]
Brazing in a vacuum or atmosphere is used for stainless steel valve bodies, stainless steel fittings, and the like because treatment of residual flux and residue is unnecessary.
In the present invention, brazing is preferably performed in a hydrogen gas reduction furnace. Hydrogen is a neutral and harmless gas, but high-purity hydrogen has a strong reducing action on metal oxides, and it is preferable to perform brazing in a hydrogen gas reduction furnace.
[0016]
In the valve chamber 4 in the valve body 1, a valve seat 5 is provided on the upper surface of the valve body 1, and a valve hole 6 is inserted between the valve seat 5 and the second joint 3 made of copper or stainless steel. A stainless steel plunger tube 7 is erected and fixed to the stainless steel valve body 1 by welding W.
[0017]
The welding W between the stainless steel valve body 1 and the stainless steel plunger tube 7 includes laser welding, electron beam welding, plasma welding, and TIG welding. TIG welding is one type of gas-encapsulated arc welding and is used for welding stainless steel materials using argon gas.
[0018]
A spherical valve element 9 is held at the tip of a plunger 8 slidably provided in the plunger tube 7, and the valve seat 5 and the spherical valve element 9 can be freely contacted and separated by the vertical movement of the plunger 8.
[0019]
A suction element 10 inserted into the plunger tube 7 is fitted to the upper end of the plunger 8, and the suction element 10 is welded to the upper end 7a of the plunger tube 7 by welding. A spring 14 is arranged between the lower end surface 11 of the suction element 10 and the concave portion 13 of the upper end surface 12 of the plunger 8 in a compressed state. An annular groove 15 is provided in the lower end surface 11 of the suction element 10, and an annular shading coil 16 is fitted and fixed in the annular groove 15. A screw hole 17 is provided in the upper part of the suction element 10. After an electromagnetic coil member (not shown) is fixed to the valve body 1 around the plunger tube 7, a screw penetrating a case that covers the periphery thereof is inserted into the screw hole 17. It is fixed by screwing.
[0020]
The spherical valve element 9 is covered with a valve element holder 20 and housed in the valve body 1. Further, a pressure equalizing passage 21 communicating from the concave portion 13 of the plunger 8 to the spherical valve body 9 is formed along the plunger axis, and a valve body spring 23 is accommodated in an enlarged portion 22 thereof, and is attached to the valve seat 5. It is being rushed. Further, the valve body holder 20 is provided with a passage 24 communicating with the pressure equalizing path 21 so that the valve chamber 4 side and the suction element 10 side are always maintained at a uniform pressure.
[0021]
To assemble the solenoid valve, first, the valve body spring 23 is housed in the enlarged portion 22 of the plunger 8, then the spherical valve body 9 is housed, and the valve body holder 24 is fixed to the plunger 8 by welding. Build the plunger assembly.
Separately, a second joint 3 made of copper or stainless steel is inserted into the lower end of the valve body 1, the first joint 2 is inserted into the outer periphery of the lower part of the valve body 1, and brazed in a hydrogen reduction furnace.
Further, the plunger tube 7 and the suction element 10 are integrated by welding W.
Next, the spring 14 and the plunger assembly are inserted into the plunger tube 7, and then the contact surface between the upper end of the valve body 1 and the lower surface of the plunger tube 7 is hermetically joined by TIG welding, plasma welding, or the like. These portions may be welded by a welding method such as laser welding or electronic beam welding. At this time, a groove 25 is provided to suppress the escape of heat during welding and to confirm the welding position with respect to the joint after welding.
[0022]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
(1) By adopting a configuration in which the valve body is replaced with stainless steel, it is possible to solve problems such as an increase in the number of parts, the number of processes, and weight while maintaining the functions of airtightness and securing a flow path. it can.
(2) Since welding of stainless steel members and brazing of the stainless steel valve body and the copper joint can be performed without flux, the possibility of adversely affecting the natural environment is reduced. In addition, the cost for managing the work environment can be reduced.
(3) Since the valve body is made of stainless steel, only the joint is brazed in an atmosphere furnace, and then the plunger tube is welded to the valve body, so that heat is applied only locally to the plunger tube. In addition, a decrease in strength can be suppressed.
(4) Also in the solenoid valve using the high-pressure refrigerant, the thickness of the plunger tube does not need to be increased, the same magnetic force as the conventional one can be secured, and the power consumption can be reduced.
[Brief description of the drawings]
FIG. 1 is a sectional view of a solenoid valve according to an embodiment of the present invention.
FIG. 2 is a sectional view of a conventional solenoid valve.
FIG. 3 is a sectional view of a conventional solenoid valve.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Stainless steel valve main body 2 Copper first joint 3 Copper second joint 4 Valve chamber 5 Valve seat 7 Plunger tube 8 Plunger 9 Spherical valve element 10 Suction element 14 Spring 15 Annular groove 16 Coil 17 Screw hole 20 Valve element holder 21 Pressure path

Claims (6)

An electromagnetic valve that opens and closes a fluid flow path, a valve body to which fluid-side inlet and outlet-side joints are connected, a valve body that opens and closes a flow path by a valve seat formed in the valve body, and A plunger for operating the valve body, a plunger tube into which the plunger is slidably inserted, and an electromagnetic coil member detachably attached to the outside of the plunger tube;
An electromagnetic valve, wherein the valve body is formed of stainless steel, the plunger tube is formed of stainless steel, and the joint is formed of copper or stainless steel. The solenoid valve according to claim 1, wherein the valve body and the plunger tube are hermetically joined by welding. 3. The solenoid valve according to claim 1, wherein the valve body and a joint attached to the valve body are hermetically joined by brazing. The solenoid valve according to claim 3, wherein the brazing is performed by flux-free brazing in an atmosphere furnace. The solenoid valve according to claim 4, wherein the brazing material is made of phosphor bronze. After the stainless steel valve body and the joints on the inlet and outlet sides of the fluid attached to the valve body are hermetically joined by brazing in an atmosphere furnace, the valve body and the stainless steel plunger tube are welded. A method for assembling a solenoid valve, characterized by joining more airtightly.

Images