JPH0552908U - Pressure control mechanism - Google Patents

Abstract

(57) [Summary] [Purpose] A pressure control mechanism with a self-aligning function that cancels the influence of the straightness of the bellows itself. [Structure] Since the valve body 21 is swingably provided on the bellows 2 via the locking portion 22, when it comes into contact with the valve seat 31, it is not affected by the straightness of the bellows 2. Only the valve body 21 swings so as to match the concentric axis of the valve seat 31. As a result, the influence of the straightness of the bellows 2 itself is canceled, and the valve body 21 is automatically aligned.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a pressure control mechanism, and more particularly to a pressure control mechanism having a self-centering function that cancels the influence of the straightness of the bellows itself.

[0002]

[Prior Art]

 In the conventional pressure control mechanism, the valve body and the bellows are fixed to each other.

That is, the conventional pressure control mechanism is arranged in a fluctuating pressure atmosphere, and a bellows that expands and contracts along the vertical direction in response to the pressure fluctuation, and is separated from one end of the bellows along the vertical direction. The valve body has a valve seat arranged facing each other, a gas vent inlet hole formed in the valve seat, and a valve body fixed to the upper end of the bellows to openably and closably cover the inlet port. , Is a mechanism that moves up and down in conjunction with the expansion and contraction motion of the bellows to change the area of the gas escape passage to the inlet.

[0004]

[Problems to be solved by the device]

 However, due to the structure and manufacturing of the bellows, the straightness of the bellows itself must be bad.

Therefore, the valve body fixed to the bellows must be affected by the straightness of the bellows itself, and as a result, the coaxiality with the valve seat inevitably varies, resulting in poor controllability and introduction. It was a cause of poor sealing of the mouth.

Therefore, in view of the above results, a technical problem of the present invention is to provide a pressure control mechanism having a self-aligning function that cancels the influence of the straightness of the bellows itself.

[0007]

According to the present invention, a pressure-sensitive element portion that is arranged in a fluctuating pressure atmosphere and expands and contracts along a predetermined direction in response to the pressure fluctuation, and the pressure-sensitive element part in the predetermined direction. A valve seat disposed along one end of the pressure sensitive element so as to be spaced apart from and opposed to the pressure sensitive element, an inlet port formed in the valve seat, and the valve seat provided at one end of the pressure sensitive element in conjunction with the expansion and contraction movement. In a pressure control mechanism having a valve body that opens and closes an inlet opening, the valve body is provided at one end of the pressure sensitive element so as to be swingable in a direction orthogonal to the predetermined direction. A pressure control mechanism characterized by the above is obtained.

Further, according to the present invention, a pressure control mechanism is formed at one end of the pressure sensing element, the locking portion locking the valve body through a predetermined clearance. Is obtained.

[0009]

[Action]

 Since the valve element that is swingably mounted on the pressure-sensitive element swings separately from the pressure-sensitive element, when it comes into contact with the valve seat, only the valve element is affected by the straightness of the pressure-sensitive element. Swing to match the central axis of the valve seat. As a result, the influence of the straightness of the bellows itself can be canceled, and the valve body can be automatically aligned.

[0010]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a case where the pressure control mechanism is used in a variable displacement type swash plate compressor will be described.

As shown in FIG. 2, the variable capacity swash plate compressor 50 has a suction chamber 51 for storing a gaseous refrigerant having a suction chamber pressure Ps and a piston 53 for discharging the gaseous refrigerant from the suction chamber 51. And a swash plate 55 for oscillating the oscillating plate 54 for driving the piston 53, and a crank case 56 having a crank internal pressure Pc.

As shown in FIG. 1, the pressure control mechanism of the present embodiment adjusts the internal crank pressure Pc in the crankcase 56. A communication hole 51a that connects the suction chamber 51 and the crankcase 56 to each other, and a bellows 2 that expands and contracts in the vertical direction in response to the crank internal pressure Pc and one end of the communication hole 51a that is linked to the expansion and contraction movement of the bellows 2. A valve body 21 that closes and opens an inlet opening to the side valve seat 31.

As shown in FIG. 3, a groove 23 is provided on a side surface of the valve body 21, and a locking portion 22 provided at an upper end of the bellows 2 is fitted therein to lock the valve body 21 to the bellows 2. The locking portion 22 and the groove 23 are provided with a predetermined clearance in the direction orthogonal to the vertical direction in FIG. 1, that is, the left and right directions in which the bellows expand and contract, and also the vertical direction. As a result, the valve body 21 is given a degree of freedom in the left-right direction with respect to the bellows 2 and can swing.

Further, the control rod 4 is provided in the valve body 21 so as to penetrate through the introduction port, and receives the discharge pressure of the discharge chamber 52 to give a negative pressure to the closing opening movement of the valve body 21. ing. The central axis of the control rod 4 coincides with the central axis of the valve seat 31.

Here, since the valve body 21 is swingably provided on the bellows 2 via the locking portion 22, when it comes into contact with the valve seat 31, it is affected by the straightness of the bellows 2. Instead, only the valve body 21 swings so as to match the concentric axis of the valve seat 31. As a result, the influence of the straightness of the bellows 2 itself is canceled, and the valve body 21 is automatically aligned.

[0016]

[Effect of the device]

 As described above, according to the present invention, since the valve body is provided so as to be swingable with respect to the pressure sensitive element, the valve body is arranged so as to be aligned with the central axis that contacts the valve body regardless of the straightness of the pressure sensitive element. Since it swings, the influence of the straightness of the bellows itself is canceled, and the valve body is automatically aligned. This makes it possible to improve pressure controllability, sealability, and productivity.

[Brief description of drawings]

FIG. 1 is a sectional view of a pressure control mechanism according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view when the pressure control mechanism shown in FIG. 1 is mounted on a variable displacement swash plate compressor.

FIG. 3 is a partially enlarged sectional view showing a locking relationship between the valve body and the bellows in FIG.

[Explanation of symbols]

 2 Bellows 21 Valve body 22 Locking part 31 Valve seat 32 Inlet port 51 Suction chamber 52 Crankcase

Claims (2)

[Scope of utility model registration request] 1. A pressure-sensitive element portion disposed in a varying pressure atmosphere and expanding and contracting along a predetermined direction in response to the pressure variation, and one end of the pressure-sensitive element spaced apart and opposed to the pressure-sensitive element portion along the predetermined direction. A valve seat, an inlet port formed in the valve seat, and a valve element that is provided at one end of the pressure-sensitive element and that opens and closes the inlet port in conjunction with the expansion and contraction movement. The pressure control mechanism according to claim 1, wherein the valve element is provided at one end of the pressure sensitive element so as to be swingable in a direction orthogonal to the predetermined direction. 2. The pressure control mechanism according to claim 1,
A pressure control mechanism, wherein a locking portion for locking the valve body via a predetermined clearance is formed at one end of the pressure sensitive element.