JP2008298013A - Control valve for variable displacement compressor and its manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve for a variable displacement compressor hardly receiving adverse effect to control from the ejection pressure Pd without complicating the configuration, and a manufacturing process thereof. <P>SOLUTION: The control valve comprises a valve rod 15 having a shaft part 15c, a middle byway small diameter part 15b with a diameter smaller than that of the shaft part 15c and a valve body part 15a with a diameter larger than that of the shaft part 15c, and a valve main body 20 having a valve chamber 1 provided with a guide hole 19 for slidably inserting the shaft part 15c of the valve rod 15 and a valve port 22 to be contacted with and separated from the valve body part 15a. The valve port 22 is set at an aperture Da capable of being inserted with the shaft part 15b before assembly of the valve. After assembly of the valve (after inserting the shaft part 15c into the guide hole 19 via the valve port 22), the effective aperture area of the valve port 22 is reduced by reducing the diameter of the valve sheet part 22a by hitting the outer periphery of the valve sheet part 22a from below with a punch, and the like. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control valve for a variable displacement compressor used in a car air conditioner and the like, and in particular, a variable displacement compressor in which a valve rod slidably inserted into a guide hole is less likely to cause a malfunction. The present invention relates to an industrial control valve and a manufacturing method thereof.

  In general, a control valve for a variable displacement compressor used in a car air conditioner or the like introduces a refrigerant having a discharge pressure Pd from a compressor (discharge chamber) in order to adjust a pressure Pc in a crank chamber of the compressor. The refrigerant having the discharge pressure Pd is squeezed out and led to the crank chamber, and the derivation amount (throttle amount) to the crank chamber is controlled according to the suction pressure Ps of the compressor. As seen in Patent Document 1 and the like, various proposals or practical applications using electromagnetic actuators (solenoids) have been made.

  A conventional example of such a variable displacement compressor control valve is shown in FIG. The illustrated control valve 5 includes a shaft portion 15c, an intermediate small diameter portion 15b having a diameter smaller than that of the shaft portion 15c, and a valve rod 15 having a valve body portion 15a having a diameter larger than that of the shaft portion 15c. The valve chamber 21 is provided with a guide hole 19 into which 15c is slidably inserted, and a valve port 22 in which the valve body portion 15a contacts and separates from the lower end portion (valve seat portion 22a). A plurality of discharge pressure refrigerant introduction ports 25 with filters 25A for introducing a refrigerant having a discharge pressure Pd from the compressor are provided on the outer peripheral portion (upstream side of the valve port 22), and below the valve port 22 (downstream side). The valve main body 20 provided with the refrigerant | coolant outlet 26 connected to the crank chamber of a compressor, and the electromagnetic actuator 30 are provided.

  The electromagnetic actuator 30 includes a coil 32 having a connector portion 31 for energization excitation, a cylindrical stator 33 disposed on the inner peripheral side of the coil 32, and a concave section that is press-fitted and fixed to the inner periphery of the lower end portion of the stator 33. Pipe-shaped suction element 34, pipe 35 with flange 35a whose upper end is joined to the outer periphery (step part) of the lower end of stator 33 by TIG welding, and the upper and lower sides of pipe 35 below the suction element 34 A plunger 37 slidably disposed in the direction and a cylindrical housing 60 with a bottomed hole disposed so as to cover the outer periphery of the coil 32 are provided.

  Further, an adjusting screw 65 having a hexagonal hole is screwed onto the stator 33, and a suction pressure Ps of the compressor is interposed between the adjusting screw 65 and the suction element 34 on the inner peripheral side of the stator 33. Is formed in the pressure sensing chamber 45. The pressure sensing chamber 45 includes a bellows 41, a reverse convex upper stopper 42, a reverse concave lower stopper 43, and a compression coil. A bellows body 40 comprising a spring 44 is disposed, and further, a compression coil that urges the bellows body 40 and the suction element 34 in a direction in which the bellows body 40 contracts (a direction in which the bellows body 40 is compressed toward the adjustment screw 65). A spring 46 is disposed. Also, a stepped operating rod 14 that passes through the suction element 34 is disposed between the lower stopper 43 (reverse concave part thereof) of the bellows body 40 and the plunger 37 (recessed part 37c thereof). A valve-opening spring 47 made of a compression coil spring that biases the valve rod 15 downward (in the valve-opening direction) via the plunger 37 is disposed between the valve 34 and the plunger 37 (the recess 37b).

  On the other hand, a convex stopper portion 28 for restricting the lowest position of the plunger 37 protrudes from the upper center of the valve body 20, and the central portion above the valve chamber including the convex stopper portion 28 includes: A guide hole 19 into which the valve stem 15 is slidably fitted is formed. In addition, a suction pressure refrigerant introduction chamber 23 into which a refrigerant having a suction pressure of the compressor is introduced is formed between the plunger 37 and the upper outer periphery (outer periphery of the convex stopper portion 28) of the valve body 20. A plurality of suction pressure refrigerant introduction ports 27 are formed on the outer peripheral side, and the refrigerant having the suction pressure Ps introduced into the suction pressure refrigerant introduction chamber 23 from the suction pressure refrigerant introduction port 27 is formed in the vertical direction formed on the outer periphery of the plunger 37. Are introduced into the pressure-sensitive chamber 45 through the grooves 37a, 37a,... And the communication hole 37d formed in the central portion, the communication hole 39 formed in the suction element 34, and the like.

  A valve closing spring 48 made of a conical compression coil spring that urges the valve rod 15 upward is disposed at the lower part (refrigerant outlet 26) of the valve body 20. Due to the force, the upper end of the valve stem 15 is always in pressure contact with the plunger 37 (the communication hole 37d portion thereof).

  Further, a lower end flange 35a of the pipe 35 is placed on the upper end portion of the valve body 20 via an O-ring 57, and a short portion with a flange 56a is provided between the flange 35a and the coil 32. A cylindrical pipe holder 56 is interposed, and the flange portions 35 a and 56 a are fastened and fixed together by an upper end outer periphery caulking portion 29 of the valve body 20. Further, the bottom portion 61 with a hole of the housing 60 is press-fitted and fixed to the upper end portion of the pipe holder 56, and the upper end portion 62 of the housing 60 is caulked and fixed on the flange-shaped portion 31 c of the connector portion 31. An O-ring 66 is interposed between the connector part 31 and the coil 32. A concave portion 31a is formed at the lower center of the connector portion 31. The concave portion 31a is formed with a convex portion 31b fitted into the hexagonal hole of the adjusting screw 65. The stator 33 and the adjusting screw are formed in the concave portion 31a. The upper part of 65 is inserted.

  In the control valve 5 having such a configuration, when the solenoid portion including the coil 32, the stator 33, and the attractor 34 is energized and energized, the plunger 37 is attracted to the attractor 34. Is moved upward (in the valve closing direction) by the urging force of the valve closing spring 48. On the other hand, the refrigerant having the suction pressure Ps introduced from the compressor to the suction pressure introduction port 27 communicates with the longitudinal grooves 37a, 37a,... Formed in the outer periphery of the plunger 37 from the introduction chamber 23 and the suction element 39. The bellows body 40 (inside the vacuum pressure) is expanded and contracted according to the pressure in the pressure sensitive chamber 45 (suction pressure Ps), and contracts and decreases when the suction pressure Ps is high. The displacement is transmitted to the valve stem 15 via the operating rod 14 and the plunger 37, whereby the valve opening (the lift amount of the valve body portion 15a from the valve seat portion 22a of the valve port 22) is increased. Adjusted. That is, the opening degree of the valve includes the attraction force of the plunger 37 by the solenoid portion including the coil 32, the stator 33 and the attraction element 34, the urging force of the bellows body 40, the urging force by the valve opening spring 47 and the valve closing spring 48, It is determined by the valve opening direction load and the valve closing direction load due to the discharge pressure Pd with respect to the valve shaft 15, and the refrigerant of the discharge pressure Pd introduced into the valve chamber 21 from the discharge pressure refrigerant introduction port 25 according to the valve opening degree. The throttle amount, that is, the lead-out amount (throttle amount) to the crank chamber is adjusted. In other words, the pressure Pc on the refrigerant outlet 26 side (hereinafter referred to as outlet pressure Pc), that is, the pressure in the crank chamber is controlled according to the valve opening, and accordingly, the inclination angle of the swash plate of the compressor and The amount of discharge is increased or decreased by adjusting the stroke of the piston.

JP 2006-291867 A

  The conventional variable displacement compressor control valve 5 as described above has the following problems to be improved.

  That is, in the control valve 5, the discharge pressure refrigerant inlet 21 is provided on the upstream side of the valve port 22, the refrigerant outlet 26 is provided on the downstream side of the valve port 22, and the valve body portion 15 a is connected to the valve rod 15. The valve port 22 is provided at the lower end portion of the shaft portion 15 c so as to open and close from the lower side thereof, and the discharge pressure Pd acts on the valve rod 15. In this case, for convenience in valve assembly, the valve port 22 can be inserted through the shaft portion 15c of the valve stem 15 from the lower side thereof as schematically shown in FIGS. As described above, the diameter Da is slightly larger than the outer diameter Db of the shaft portion 15c, and the valve port 22 is opened and closed by the valve body portion 15a from below (a valve provided at the lower end portion of the valve port 22). The outer diameter Dc of the valve body portion 15a is made larger than the diameter Da of the valve port 22 (Db ≦ Da <Dc) so that the valve body portion 15a contacts and separates from the seat portion 22a.

  In this case, the valve closing direction load (push-up force) A due to the discharge pressure Pd acting on the valve stem 15 corresponds to the pressure receiving area (outer diameter Db) of the shaft portion 15c, whereas the valve opening direction load ( The pressing force (B) has a magnitude obtained by adding a load Bb corresponding to the outer diameter Dc (Dc-Da) of the valve body 15a to a load Ba corresponding to the diameter Da of the valve port 22 (valve seat portion 22a). .

  Here, since it may be assumed that Da and Db are substantially equal, the valve opening direction load (pressing force) due to the discharge pressure Pd on the valve rod 15 is larger than the valve closing direction load (pushing force) by about the load Bb. Become. Therefore, if the current value I supplied to the coil 32 of the electromagnetic actuator 30 is constant, as the discharge pressure Pd increases, the outlet pressure Pc and hence the suction pressure Ps (as shown in the Pd-Ps characteristic in FIG. Due to the use of the compressor, the outlet pressure Pc and the suction pressure Ps tend to be higher (upward to the right), which adversely affects the control (deteriorates control accuracy, etc.). It was.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a control valve for a variable displacement compressor that can hardly be adversely affected by the control by the discharge pressure Pd without complicating the configuration. It is in providing the manufacturing method.

  In order to achieve the above object, a control valve for a variable displacement compressor according to the present invention basically includes a shaft portion, an intermediate small diameter portion having a smaller diameter than the shaft portion, and a valve body having a larger diameter than the shaft portion. A valve stem having a valve portion, a guide hole into which a shaft portion of the valve rod is slidably inserted, and a valve chamber provided with a valve port through which the valve body portion contacts and separates, and discharge pressure from the compressor A valve main body provided with a discharge pressure refrigerant inlet for introducing the refrigerant of (Pd) on the upstream side of the valve port and a refrigerant outlet communicating with the crank chamber of the compressor on the downstream side of the valve port And an electromagnetic actuator for driving the valve stem in the valve opening / closing direction, and a pressure sensitive responsive member for driving the valve stem in the valve opening / closing direction in response to the suction pressure (Ps) of the compressor Prepare.

  The valve body portion is provided below the intermediate small-diameter portion of the valve stem, and is configured to open and close the valve port from the lower side thereof. The diameter is set so that the shaft portion of the shaft can be inserted, and the effective opening area is reduced after the valve is assembled.

  In a preferred embodiment, a valve seat portion that contacts and separates the valve body portion is provided at a lower end portion of the valve port, and the valve seat portion is narrowed from an upper portion of the valve port.

  The valve seat portion is preferably reduced in diameter by punching the outer periphery with a punch or the like after the valve assembly.

  In another preferred embodiment, the effective opening area of the valve port is set so that the suction pressure (Ps) maintains a substantially constant value or slightly decreases even when the discharge pressure (Pd) increases. Is done.

  In a more preferable aspect, the valve opening direction load and the valve closing direction load due to the discharge pressure (Pd) with respect to the valve shaft are substantially equal, or the valve closing direction load is slightly larger than the valve opening direction load. An effective opening area of the valve port is set.

  On the other hand, a method for manufacturing a control valve for a variable displacement compressor according to the present invention includes a shaft, an intermediate small diameter portion having a smaller diameter than the shaft portion, and a valve stem having a valve body portion having a larger diameter than the shaft portion, It has a guide hole into which the shaft portion of the valve stem is slidably inserted and a valve chamber provided with a valve port for contacting and separating the valve body portion, and introduces a refrigerant having a discharge pressure (Pd) from the compressor. And a valve body provided with a refrigerant outlet communicating with a crank chamber of the compressor on the downstream side of the valve port, and a valve rod connected to the valve rod. For variable displacement compressors comprising an electromagnetic actuator for driving in the opening / closing direction and a pressure sensitive response member for driving the valve stem in the valve opening / closing direction in response to the suction pressure (Ps) of the compressor A method for manufacturing a control valve, in which a valve shaft shaft portion is moved forward through the valve port during valve assembly. Inserted into the guide hole, after insertion of the shaft portion, it is characterized in that a step of reducing the effective aperture area of the valve port.

  In this case, preferably, the diameter of the valve seat portion is reduced by punching the outer periphery of the valve seat portion provided at the lower end portion of the valve port with a punch or the like.

  In the control valve for a variable displacement compressor according to the present invention, before the valve assembly, as in the conventional example described above, the valve port can be inserted through the shaft portion of the valve stem from below. The diameter is made larger than the outer diameter of the shaft part, and the valve port is opened and closed by the valve body part from below (so that the valve body part comes into contact with and separates from the valve seat part provided at the lower end part of the valve port. The outer diameter of the valve body is larger than the diameter of the valve opening. After the valve assembly (after inserting the shaft portion of the valve stem into the guide hole through the valve opening), for example, the valve seat The valve seat portion is reduced in diameter by pressing the outer periphery of the portion with a punch or the like from below to reduce the effective opening area of the valve port.

  In this way, by reducing the effective opening area of the valve opening, the valve opening direction load (pushing force) due to the discharge pressure Pd on the valve stem is substantially equal to or slightly smaller than the valve closing direction load (pushing force). be able to.

  As a result, if the current value I supplied to the coil of the electromagnetic actuator is constant, the suction pressure Ps (use of the compressor) can be obtained even when the discharge pressure Pd increases as shown by the Pd-Ps characteristic in FIG. In addition, the outlet pressure Pc and the suction pressure Ps are approximately equal to each other, as indicated by the solid line V, or have a characteristic of being slightly lowered as indicated by the alternate long and short dash line U. As a result, the control by the discharge pressure Pd can be hardly affected without complicating the configuration.

  Hereinafter, embodiments of a control valve for a variable displacement compressor of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an embodiment of a control valve for a variable displacement compressor according to the present invention. In the variable displacement compressor control valve 1 shown in FIG. 1, parts corresponding to those of the conventional variable displacement compressor control valve 5 shown in FIG. The duplicate description is omitted, and the differences will be mainly described below.

  In the control valve 1 of the illustrated embodiment, before the valve assembly, as shown in FIG. 2 (A), the valve port 22 is provided for convenience of valve assembly as in the conventional example described above. The diameter Da is made slightly larger than the outer diameter Db of the shaft portion 15c so that the shaft portion 15c of the valve stem 15 can be inserted from the lower side thereof, and the valve port 22 is formed from the lower side by the valve body portion 15a. In order to open and close (so that the valve body portion 15a contacts and separates from the valve seat portion 22a provided at the lower end portion of the valve port 22), the outer diameter Dc of the valve body portion 15a is made larger than the diameter Da of the valve port 22. However, as will be described later, a step of reducing the effective opening area of the valve port 22 after the valve assembly is performed.

  Further, in this embodiment, the valve rod 15 and the operating rod 14 are integrated, and in the conventional example, the valve rod 15 is urged upward by a valve closing spring 48 and pressed against the plunger 37. However, in this embodiment, the valve closing spring 48 is not provided, and an annular groove portion (small diameter portion) is formed at the boundary between the shaft portion 15c of the valve shaft 15 and the large diameter portion 14b (same diameter as the shaft portion 15c) of the operating rod 14. ) 15d is provided, and a locking portion 38 provided at the bottom of the concave hole 37g of the plunger 37 is fitted into the annular groove 15d so that the valve stem 15 and the plunger 37 can be moved up and down integrally. It has become.

  This is for the following reason. That is, when the valve rod 15 is moved in the valve closing direction only by the urging force of the valve closing spring 48 as in the conventional example, foreign matter is clogged between the sliding contact surfaces of the valve rod 15 and the guide hole 19. If the sliding resistance of the valve stem 15 increases due to oil seizure or the like, the valve stem 15 will move in the valve closing direction even if the valve stem 15 locks, for example, even if the plunger is attracted to the suction element. In this case, the valve opening is not properly adjusted, but the valve rod 15 and the plunger 37 are substantially directly connected as described above. Such a problem is solved, and the valve closing spring 48 becomes unnecessary.

  Then, in the control valve 1 of the present embodiment, after the valve assembly, that is, after the shaft portion 15c of the operating rod 14 and the valve rod 15 is inserted and inserted into the guide hole 19 through the valve port 22, FIG. As shown in the figure, a cylindrical punch 80 is inserted into the refrigerant outlet 26 on the lower side of the valve port 22, and the cross-section protruding from the upper end surface of the punch 80 is a wedge-shaped or triangular-shaped annular shaped portion 81. The lower end portion of the mouth 22 (the outer periphery of the valve seat portion 22a provided on the mouth 22) is pushed from below. In this case, the outer diameter Dm and the inner diameter Dn of the punch 80 are sized to be slidably inserted into the refrigerant outlet 26 and the valve body 15a, respectively, and the peak diameter of the annular molded portion 81 is The valve port 22 (the valve seat portion 22a provided on the valve seat 22a) is made larger than the diameter Da by a predetermined length.

  Thus, the punch 80 presses the lower end portion of the valve port 22 (the outer periphery of the valve seat portion 22a provided on the lower side) from the lower side thereof, as shown in FIGS. 2 (C) and 3 (A). As described above, when the annular molded portion 81 is pushed into the lower end portion of the valve port 22 (the outer periphery of the valve seat portion 22a), an annular recess 22c is formed, and the lower end portion (the valve seat portion 22a) is inward. The diameter Dd of the valve seat portion 22a which is squeezed out and squeezed out and is squeezed inwardly is reduced to be smaller than the caliber Da of the upper part (Dd <Db <Da <Dc). The effective opening area of 22 is reduced.

  In this way, by reducing the effective opening area of the valve port 22, as shown in FIG. 3B, the valve closing direction load (push-up force) A due to the discharge pressure Pd acting on the valve stem 15 is as shown in FIG. However, the valve opening direction load (pressing force) B ′ is the same as that of the conventional one shown in FIG. A load Bb ′ (Bb ′> Bb) corresponding to the outer diameter Dc (Dc−Da) of the valve body 15a is added to the load Ba ′ (Ba ′ <Ba) corresponding to the diameter Dd of the valve seat portion 22a). Accordingly, by appropriately narrowing the valve seat portion 22a, the valve opening direction load B ′ and the valve closing direction load A due to the discharge pressure Pd to the valve rod 15 are substantially equal, or the valve opening direction load The valve closing direction load A is slightly larger than B '. It can be set.

  As a result, in the control valve 1 of the present embodiment, when the current value I supplied to the coil 32 of the electromagnetic actuator 30 is constant, the discharge is performed as shown in the Pd-Ps characteristic in FIG. Even if the pressure Pd increases, the suction pressure Ps (the outlet pressure Pc and the suction pressure Ps are substantially equal to each other in the use of the compressor) is maintained at a substantially constant value as indicated by the solid line V, or one point. As indicated by the chain line U, it has a slightly lower characteristic, and as a result, it is difficult to adversely affect the control by the discharge pressure Pd without complicating the configuration.

  In the above embodiment, the punch 80 is used to reduce the effective opening area of the valve port 22 after the assembly of the valve, but other means are used to reduce the effective opening area of the valve port 22. Of course, it may be.

The longitudinal section showing one embodiment of the control valve for variable capacity type compressors concerning the present invention. The figure which is provided for description of the manufacturing method of the control valve shown in FIG. The principal part expansion longitudinal cross-sectional view (A) and effect | action explanatory drawing (B) of the control valve shown by FIG. The principal part expansion longitudinal cross-sectional view (A) and effect | action explanatory drawing (B) of an example of the conventional control valve for variable displacement compressors. The graph which shows the Pd-Ps characteristic of the control valve shown by FIG. The graph which shows the Pd-Ps characteristic of an example of the conventional control valve for variable displacement compressors. The longitudinal cross-sectional view which shows an example of the conventional control valve for variable displacement compressors.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control valve 14 for variable capacity type compressors Actuating rod 15 Valve rod 15a Valve body portion 15b Intermediate small diameter portion 15c Shaft portion 19 Guide hole 20 Valve body 21 Valve chamber 22 Valve port 22a Valve seat portion 25 Discharge pressure refrigerant introduction port 26 Refrigerant Outlet 27 Suction pressure refrigerant introduction port 30 Electromagnetic actuator 32 Coil 33 Stator 37 Plunger 40 Bellows body 45 Pressure sensing chamber 47 Valve opening spring 80 Punch Da Diameter of valve port (valve seat portion) before valve assembly Dd Valve after valve assembly Port (valve seat) diameter

Claims (7)

A valve stem having a shaft portion, an intermediate small diameter portion having a diameter smaller than that of the shaft portion, and a valve body portion having a diameter larger than that of the shaft portion, a guide hole into which the shaft portion of the valve rod is slidably inserted, and the valve body And a valve chamber provided with a valve port that contacts and separates, a discharge pressure refrigerant inlet for introducing a refrigerant of discharge pressure (Pd) from the compressor is provided upstream from the valve port, and A valve body provided with a refrigerant outlet communicating with the crank chamber of the compressor downstream from the valve port, an electromagnetic actuator for driving the valve rod in the valve opening / closing direction, and a suction pressure of the compressor ( Ps) is a variable displacement compressor control valve provided with a pressure sensitive response member that drives the valve stem in the valve opening / closing direction in response to Ps),
The valve body portion is provided below the intermediate small-diameter portion of the valve stem, and is configured to open and close the valve port from the lower side thereof. A control valve for a variable displacement compressor, which is set to a diameter that allows the shaft portion to be inserted, and whose effective opening area is reduced after the valve is assembled.   2. The variable capacity according to claim 1, wherein a valve seat portion that contacts and separates the valve body portion is provided at a lower end portion of the valve port, and the valve seat portion is narrowed from an upper portion of the valve port. Control valve for type compressor.   3. The control valve for a variable displacement compressor according to claim 2, wherein the valve seat portion is reduced in diameter by being struck by a punch or the like after the valve is assembled.   The effective opening area of the valve port is set so that the suction pressure (Ps) maintains a substantially constant value or slightly decreases even when the discharge pressure (Pd) increases. The control valve for a variable displacement compressor according to any one of claims 1 to 3.   The valve opening is effective so that the valve opening direction load and the valve closing direction load due to the discharge pressure (Pd) to the valve stem are substantially equal, or the valve closing direction load is slightly larger than the valve opening direction load. The control valve for a variable displacement compressor according to any one of claims 1 to 3, wherein an opening area is set. A valve stem having a shaft portion, an intermediate small diameter portion having a diameter smaller than that of the shaft portion, and a valve body portion having a diameter larger than that of the shaft portion, a guide hole into which the shaft portion of the valve rod is slidably inserted, and the valve body And a valve chamber provided with a valve port that contacts and separates, a discharge pressure refrigerant inlet for introducing a refrigerant of discharge pressure (Pd) from the compressor is provided upstream from the valve port, and A valve body provided with a refrigerant outlet communicating with the crank chamber of the compressor downstream from the valve port, an electromagnetic actuator for driving the valve rod in the valve opening / closing direction, and a suction pressure of the compressor ( Ps), and a pressure-sensitive responsive member that drives the valve stem in the valve opening / closing direction.
When assembling a valve, the shaft portion of the valve stem is inserted into the guide hole through the valve port, and the step of reducing the effective opening area of the valve port is performed after the shaft portion is inserted. Method for manufacturing control valve for type compressor.   7. The variable capacity compressor according to claim 6, wherein the valve seat portion is reduced in diameter by punching an outer periphery of a valve seat portion provided at a lower end portion of the valve port with a punch or the like. Manufacturing method of control valve.

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