Method of manufacturing an assembled body composed of a plurality of members, manufacturing method of electromagnetic control valve, and control valve for variable capacity compressors

Abstract

There is provided a brazing method which makes it possible to rationally perform not only the brazing between a metal member such as a stator made of a magnetic material and a metal member such as a guide pipe made of a non-magnetic material but also the magnetic annealing of these metal members. By making use of a brazing material ( 90 ) which can be fused at a lower temperature than a magnetic annealing temperature of metal member ( 33 ), the metal member such as a stator made of a magnetic material and the metal member ( 35 ) such as a guide pipe made of a non-magnetic material are heated to a predetermined temperature in a furnace to perform the magnetic annealing of the metal member ( 33 ) concurrent with the brazing of these metal members.

1 . A method of manufacturing an assembled body composed of a plurality of members including a metal member “A” made of a magnetic material and a metal member “B” made of a non-magnetic material, the method comprising the steps of: 
 heating the metal member “A” and the metal member “B” under conditions suitable for magnetic annealing of the metal member “A” to braze the metal member “A” to the metal member “B” to obtain an assembled body comprising the metal member “A” and the metal member “B”; and    gradually cooling the assembled body to perform magnetic annealing of the metal member “A”.    
   
   
       2 . The method according to  claim 1 , wherein the metal member “A” is brazed to the metal member “B” by making use of a brazing material having a melting point which is lower than a magnetic annealing temperature of the metal member “A”.  
   
   
       3 . The method according to  claim 1 , wherein the metal member “A” is made of a magnetic steel such as an electromagnetic stainless steel, the metal member “B” is made of a non-magnetic steel material such as non-magnetic stainless steel, and the brazing material is made of copper wax or bronze wax.  
   
   
       4 . The method according to  claim 1 , wherein the metal member “A” is formed of a step-attached columnar or cylindrical body having a diametrally contracted end portion and a terrace surface, the metal member “B” is formed of a cylindrical body having an inner diameter which is large enough to enable it to externally fit on the diametrally contracted end portion, the diametrally contracted end portion of the metal member “A” is provided, at an extended end portion thereof which is remote from the terrace surface, with an annular groove facing an inner peripheral surface of the metal member “B” for holding a brazing material therein, and the brazing is performed under conditions wherein the metal member “B” is externally fitted on the diametrally contracted end portion with an fitted end of the metal member “B” being butted against the terrace surface and the brazing material being held between the annular groove and the inner peripheral surface of the metal member “B”.  
   
   
       5 . The method according to  claim 1 , wherein the metal member “A” is a stator of an electromagnetic control valve, and the metal member “B” is a guide pipe to be used as a plunger guide of the electromagnetic control valve.  
   
   
       6 . A method for manufacturing an electromagnetic control valve provided with an assembled body comprising a stator made of a magnetic metallic material, a guide pipe for use as a plunger guide which is fixedly coupled to an lower end portion of the stator and made of a non-magnetic metallic material, a holder fixedly coupled to an lower end portion of the guide pipe and made of a metallic material, and a housing fixedly coupled to the holder and made of a magnetic metallic material; 
 wherein the stator is formed of a step-attached columnar or cylindrical body having a diametrally contracted end portion and a terrace surface, the guide pipe is formed of a cylindrical body having an inner diameter which is large enough to enable it to externally fit on the diametrally contracted end portion, the diametrally contracted end portion of the stator is provided, at an extended end portion thereof which is remote from the terrace surface, with an annular groove facing an inner peripheral surface of the guide pipe for holding a brazing material therein, the guide pipe is externally fitted on the diametrally contracted end portion with an fitted end of the guide pipe being butted against the terrace surface to thereby temporarily interconnect the stator, the guide pipe, the holder and the housing, the brazing material is held between the annular groove and the inner peripheral surface of the guide pipe;    the method being characterized in that it comprises the steps of heating the temporarily interconnected assembled body under conditions for effecting magnetic annealing of the magnetic metallic material such as the stator; and gradually cooling the assembled body to perform magnetic annealing of the stator, the holder and the housing.    
   
   
       7 . The method according to  claim 6 , wherein the housing is fabricated into a configuration enabling the housing to be press-inserted into the holder, the holder and housing are subjected to nickel plating or chrome plating, and the plated housing is press-inserted into the holder, thereby fabricating the temporarily interconnected assembled body.  
   
   
       8 . The method according to  claim 6 , wherein the holder is formed into a step-attached cylindrical body to thereby enable the guide pipe to be snugly inserted therein, and the fabrication of the temporarily interconnected assembled body is performed by inserting the guide pipe into the holder and, at the same time, by disposing the brazing material at an interface between the inserted portion of the guide pipe and the holder.  
   
   
       9 . An electromagnetic control valve to be manufactured by the method according to  claim 6 .  
   
   
       10 . A control valve for a variable capacity compressor, which comprises: 
 a valve rod having a valve body;    a valve main body provided with a valve chamber having a valve aperture with which the valve body can be retractivebly contacted, with an inlet port for cooling medium of discharge pressure which is disposed on an upstream side of the valve aperture, and with a cooling medium outlet port which is disposed on a downstream side of the valve aperture and communicated with a crank chamber of the compressor;    an electromagnetic actuator for driving the valve rod to move in the direction of opening or closing the valve aperture; and    a pressure sensitive moving member for driving the valve rod to move in the direction of opening or closing the valve aperture in response to a sucking pressure of the compressor;    wherein the cooling medium outlet port is further provided with a restricting mechanism for restricting a maximum flow rate of the cooling medium to be fed to the crank chamber.    
   
   
       11 . The control valve for a variable capacity compressor according to  claim 10 , wherein the restricting mechanism is constituted by a restricting pore-attached closing member which is secured to the cooling medium outlet port.  
   
   
       12 . The control valve for a variable capacity compressor according to  claim 10 , wherein the restricting mechanism is designed to regulate the magnitude of opening of valve in order to inhibit changes in gradient of controlling pressure.  
   
   
       13 . The control valve for a variable capacity compressor according to  claim 12 , wherein the magnitude of lift of the valve body from the valve aperture is regulated for regulating the magnitude of opening of valve.  
   
   
       14 . A crutch-attached compressor comprising the control valve for a variable capacity compressor which is claimed in  claim 10 .  
   
   
       15 . A control valve for a variable capacity compressor, which comprises: 
 a valve rod having a valve body;    a valve main body provided with a valve chamber having a valve aperture with which the valve body can be retractivebly contacted, with an inlet port for introducing cooling medium of discharge pressure from a compressor, the inlet port being disposed on an upstream side of the valve aperture, and with a cooling medium outlet port which is disposed on a downstream side of the valve aperture and communicated with a crank chamber of the compressor;    an electromagnetic actuator constituted by a coil, a cylindrical stator disposed on the inner peripheral side of the coil, a sucking member secured to the stator, and a plunger disposed below the sucking member and enabled to slide up and down;    a pressure sensitive chamber which is formed on the inner peripheral side of the stator and over the sucking member and to which an inlet pressure is introduced therein from the compressor;    a pressure sensitive driving member disposed in the pressure-sensitive chamber; and    an operating rod interposed between a pressure sensitive driving member and the plunger;    wherein the valve body is designed to be moved in the valve-closing direction as the plunger is moved close to the sucking member and in the valve-opening direction as the operating rod is pushed downward by the actuation of the pressure sensitive driving member; and the cooling medium outlet port is further provided with a restricting mechanism for restricting a maximum flow rate of the cooling medium to be fed to the crank chamber.    
   
   
       16 . The control valve for a variable capacity compressor according to  claim 15 , wherein the restricting pore-attached closing member is provided with one or a plurality of restricting pores, a total area of aperture of the restricting pore-attached closing member is less than a maximum effective aperture area of the valve aperture.  
   
   
       17 . The control valve for a variable capacity compressor according to  claim 15 , wherein the restricting mechanism is constituted by a restricting pore-attached closing member which is secured to the cooling medium outlet port.  
   
   
       18 . The control valve for a variable capacity compressor according to  claim 15 , wherein the restricting mechanism is designed to regulate the magnitude of opening of valve in order to inhibit changes in gradient of controlling pressure.  
   
   
       19 . The control valve for a variable capacity compressor according to  claim 18 , wherein the magnitude of lift of the valve body from the valve aperture is regulated for regulating the magnitude of opening of valve.  
   
   
       20 . A crutch-attached compressor comprising the control valve for a variable capacity compressor which is claimed in  claim 15.