JP4368255B2 - Reciprocating compressor - Google Patents

Description

  The present invention relates to a cylinder plate having a bore, a piston that reciprocates in the bore, a valve plate having a suction hole and a discharge hole facing the bore, and a valve plate equipped with a suction valve and a discharge valve. And a cylinder head that defines a suction chamber communicating with the suction hole and a discharge chamber communicating with the suction hole in cooperation with the cylinder block, and the opening of the suction valve on the valve plate side end peripheral wall of the bore The present invention relates to a reciprocating compressor in which a locking recess for regulating the above is formed.

Cylinder block having a cylinder block formed with a bore, a piston that reciprocates in the bore, a valve plate formed with a suction hole and a discharge hole facing the bore, and a valve plate equipped with a suction valve and a discharge valve And a cylinder head that defines a suction chamber that is sandwiched and communicates with the suction hole and a discharge chamber that communicates with the discharge hole, and restricts the opening degree of the suction valve on the peripheral wall of the valve plate side end of the bore A reciprocating compressor in which a locking recess is formed is described in FIGS.
Japanese Utility Model Publication No. 3-35899

13 to 15 of Patent Document 1, when the compressor is operated with a small capacity, the tip of the suction valve does not come into contact with the bottom surface of the locking recess, and the cantilever The suction valve in the beam state is self-excited and the refrigerant gas passage cross-sectional area near the suction valve fluctuates to generate pressure fluctuations in the refrigerant gas in the vicinity. There is a problem that the evaporator of the circuit resonates and noise is generated.
The present invention has been made in view of the above problems, a cylinder block formed with a bore, a piston reciprocating in the bore, a valve plate formed with a suction hole and a discharge hole facing the bore, A bore valve comprising: a valve plate equipped with a suction valve and a discharge valve; and a cylinder head defining a suction chamber communicating with the suction hole and a discharge chamber communicating with the discharge hole. A reciprocating compressor in which a stopper recess for restricting the opening degree of the suction valve is formed on the peripheral wall of the plate side end, and the suction valve does not cause self-excited vibration when the compressor is operated at a small capacity. An object of the present invention is to provide a reciprocating compressor in which an increase in pressure loss at a suction valve portion is suppressed when the compressor is operated at a large capacity.

In order to solve the above problems, in the present invention, a cylinder block formed with a bore, a rotary shaft that is driven to rotate by an external drive source, and a piston that reciprocates within the bore following the rotation of the rotary shaft. A suction chamber and a discharge hole that communicate with the suction hole by holding a valve plate having a suction hole and a discharge hole facing the bore, and a valve plate equipped with the suction valve and the discharge valve in cooperation with the cylinder block A reciprocating compressor including a cylinder head defining a discharge chamber communicating with the valve, and having a locking recess for restricting an opening degree of a suction valve formed on a peripheral wall of a valve plate side end of a bore, An opening having a smaller diameter than the suction hole facing the suction hole is formed in the suction valve, and includes a sub suction valve that covers the opening on the side away from the valve plate and contacts the suction valve. Offset toward the center of the bore from the tip of the intake valve, the locking recess Provided is a reciprocating compressor characterized in that it is formed in a stepped shape consisting of a first recess that only an intake valve locks and a second recess that is locked only by a sub-intake valve and deeper than the first recess. To do.

When the reciprocating compressor is operated at a small capacity, the differential pressure between the suction chamber pressure and the bore pressure is small and the gas flow rate into the bore is small. With the suction force of the lubricating oil film interposed between them, the valves are integrally opened while sticking to each other, and the suction valve is in contact with the first recess of the locking recess while both are integrated, and the opening degree of both is regulated. Is done. Since the first recess is shallower than the second recess, the suction valve reliably contacts the first recess. Therefore, the suction valve and the auxiliary suction valve do not cause self-excited vibration.
When the reciprocating compressor is operated at a large capacity, the pressure difference between the suction chamber pressure and the bore pressure is large, and the gas flow rate into the bore is large. The suction valve is brought into contact with the first recess of the locking recess while the both are integrated, and then the auxiliary suction valve is separated from the suction valve against the suction force of the lubricating oil film. The valve is peeled off and further opened to contact the second recess of the locking recess. The auxiliary intake valve that receives the dynamic pressure of the high-speed gas flowing in from the opening formed in the intake valve surely contacts the second recess that is deeper than the first recess. Therefore, the auxiliary suction valve does not cause self-excited vibration. Gas flows into the bore not only from the gap between the intake valve and the valve plate, but also from the opening formed in the intake valve, thereby suppressing an increase in pressure loss at the intake valve during large capacity operation. The

In a preferred aspect of the present invention, the outer diameter of the seal portion of the auxiliary intake valve is smaller than the outer diameter of the seal portion of the intake valve, and the intake valve relief step formed on the end face of the cylinder block is the intake valve step and the intake valve step. It is formed in a staircase shape having a step for the auxiliary intake valve deeper than the step for use.
Make the outer diameter of the seal part of the auxiliary intake valve smaller than the outer diameter of the seal part of the intake valve, and make the intake valve relief step formed on the end face of the cylinder block deeper than the intake valve step and the intake valve step. By forming a stepped shape consisting of a valve step, the gasket for sealing inserted between the end face of the cylinder block and the valve plate is prevented from abruptly deforming at the suction valve escape step portion, Damage to the sealing gasket is prevented.

When the reciprocating compressor according to the present invention is operated at a small capacity, the differential pressure between the suction chamber pressure and the bore pressure is small, and the gas flow rate flowing into the bore is small. Is opened as a single unit while adhering to each other due to the suction force of the lubricating oil film interposed between them, and the suction valve abuts against the first concave portion of the locking concave portion while both are united. Opening is regulated. Since the first recess is shallower than the second recess, the suction valve reliably contacts the first recess. Therefore, the suction valve and the auxiliary suction valve do not cause self-excited vibration.
When the reciprocating compressor is operated at a large capacity, the pressure difference between the suction chamber pressure and the bore pressure is large, and the gas flow rate into the bore is large. The suction valve is brought into contact with the first recess of the latching recess while the both are integrated, and the auxiliary suction valve is separated from the suction valve against the suction force of the lubricating oil film. The valve is peeled off and further opened to contact the second recess of the locking recess. The auxiliary intake valve that receives the dynamic pressure of the high-speed gas flowing in from the opening formed in the intake valve surely contacts the second recess that is deeper than the first recess. Therefore, the auxiliary suction valve does not cause self-excited vibration. Gas flows into the bore not only from the gap between the intake valve and the valve plate, but also from the opening formed in the intake valve, thereby suppressing an increase in pressure loss at the intake valve during large capacity operation. The

  A reciprocating compressor according to an embodiment of the present invention will be described.

As shown in FIG. 1, a front housing 2 and a cylinder head 3 are disposed so as to cover both ends of a columnar cylinder block 1. A crank chamber 4 is formed inside the front housing 2, and a plurality of cylinder bores 5 are formed inside the cylinder block 1 at intervals in the circumferential direction. A swash plate 6 is disposed in the crank chamber 4. A drive shaft 7 is inserted through the center of the swash plate 6. The drive shaft 7 is rotatably supported by the front housing 2 and the cylinder block 1 via a bearing (not shown).
A rotor 8 is fixed to the drive shaft 7. The rotor 8 is supported by the front housing 2 via a thrust bearing 9.
The swash plate 6 is connected to the rotor 8 via the link mechanism 10 so as to be capable of varying the tilt angle with respect to the drive shaft 7 and not to be rotatable relative to the rotor 8 around the drive shaft 7.

  A piston 12 is engaged with the swash plate 6 via a shoe 11. The piston 12 is inserted into the cylinder bore 5 so as to be slidable back and forth.

A suction chamber 13 and a discharge chamber 14 are defined inside the cylinder head 3. A suction port 3 a formed in the cylinder head 3 communicates with the suction chamber 13. A discharge port (not shown) formed in the cylinder head 3 communicates with the discharge chamber 14.
A gasket 15 and a valve plate 16 are disposed between the cylinder block 1 and the cylinder head 3. The valve plate 16 is formed with a suction hole 16 a communicating with the cylinder bore 5 and the suction chamber 13 and a discharge hole 16 b communicating with the cylinder bore 5 and the discharge chamber 14. The valve plate 15 is equipped with a suction valve 17 that opens and closes the suction hole 16 a on the side away from the suction chamber 13, a sub suction valve 18, and a discharge valve 19 that opens and closes the discharge hole 16 b on the discharge chamber 14 side. The suction valve 17, the sub suction valve 18, and the discharge valve 19 are configured as lead type valves that open and close the suction hole 16a and the discharge hole 16b by elastically deforming in the out-of-plane direction due to a pressure difference between the inside and outside.
As shown in FIGS. 1 and 2, an opening 17 a having a smaller diameter than the suction hole 16 a is formed in the suction valve 17 so as to face the suction hole 16 a. The suction valve 17 and the discharge valve 19 are in contact with the valve plate 16, and the auxiliary suction valve 18 is in contact with the suction valve 17 so as to cover the opening 17 a on the side away from the suction chamber 13. As can be seen from FIGS. 1 and 2, the tip of the auxiliary suction valve 18 is offset from the tip of the suction valve 17 toward the center of the bore 5.

  As shown in FIGS. 1 and 2A, a locking recess 20 for restricting the opening degree of the suction valve 17 and the auxiliary suction valve 18 is formed on the peripheral wall of the cylinder bore 5 on the valve plate 16 side. The locking recess 20 includes a first recess 20a that is locked only by the tip of the suction valve 17, and a second recess 20b that is locked only by the tip of the auxiliary suction valve 18 and deeper than the first recess 20a. It is formed in a staircase shape

  As shown in FIG. 2 (b), the outer diameter of the seal portion of the auxiliary intake valve 18 is set smaller than the outer diameter of the seal portion of the intake valve 17, and the intake valve relief step 21 formed on the end face of the cylinder block 1 is It is formed in a staircase shape comprising a suction valve step 21a and a sub suction valve step 21b deeper than the suction valve step 21a.

The operation of the reciprocating compressor will be described below.
The drive shaft 7 is rotationally driven by an external drive source (not shown), and the swash plate 6 rotates as the drive shaft 7 rotates. As the swash plate 6 rotates, the piston 12 reciprocates in the cylinder bore 5. As the piston 12 reciprocates, the refrigerant gas that has flowed from the external refrigeration circuit through the suction port 3a into the suction chamber 13 passes through the suction hole 16a, the opening 17a and the auxiliary suction valve 18, or is sucked into the suction hole 16a. It is sucked into the bore 5 through the valve 17, compressed in the bore 5, discharged into the discharge chamber 14 through the discharge hole 16 b and the discharge valve 19, and from the discharge chamber 14 through a discharge port (not shown). Outflow to external refrigeration circuit.

When the reciprocating compressor is operated at a small capacity, the differential pressure between the internal pressure of the suction chamber 13 and the internal pressure of the bore 5 is small, and the flow rate of the refrigerant gas flowing into the bore 5 is small, as shown in FIG. In the suction stroke, the suction valve 17 and the auxiliary suction valve 18 are opened together while sticking to each other by the suction force of the lubricating oil film interposed between them, and the suction valve 17 is kept in a state where both are integrated. The first recess 20a of the locking recess 20 abuts and the opening degree of both is regulated. Since the 1st recessed part 20a is shallower than the 2nd recessed part 20b, the suction valve 17 contacts the 1st recessed part 20a reliably. Therefore, the suction valve 17 and the auxiliary suction valve 18 do not cause self-excited vibration.

When the reciprocating compressor is operated at a large capacity, the pressure difference between the internal pressure of the suction chamber 13 and the internal pressure of the bore 5 is large, and the flow rate of the refrigerant gas flowing into the bore 5 is large. In the intake stroke, the intake valve 17 and the auxiliary intake valve 18 are integrally opened while sticking to each other, and the intake valve 17 is in contact with the first recess 20a of the locking recess 20 while both are integrated. After that, as shown in FIG. 4, the auxiliary suction valve 18 is peeled off from the suction valve 17 against the suction force of the lubricating oil film and further opened, and comes into contact with the second recess 20 b of the locking recess 20. The sub suction valve 18 that receives the dynamic pressure of the high-speed refrigerant gas flowing from the opening 17a formed in the suction valve 17 surely contacts the second recess 20b deeper than the first recess 20a. Therefore, the auxiliary suction valve 18 does not cause self-excited vibration. The refrigerant gas flows into the bore 5 not only from the gap between the suction valve 17 and the valve plate 16 but also from the opening 17a formed in the suction valve 17, so that the pressure at the suction valve portion during large capacity operation is increased. Increase in loss is suppressed.

In this reciprocating compressor, the outer diameter of the seal portion of the auxiliary intake valve 18 is made smaller than the outer diameter of the seal portion of the intake valve 17, and the intake valve relief step 21 formed on the end face of the cylinder block 1 is used for the intake valve. Since the step 21a and the step 21b for the auxiliary intake valve deeper than the step 21a for the intake valve are formed in a stepped shape, as can be seen from FIG. 2 (b), between the end face of the cylinder block 1 and the valve plate 16 Abrupt deformation of the inserted sealing gasket 15 at the suction valve escape step 20 is prevented, and damage to the sealing gasket 15 at this portion is prevented.

The present invention relates to a cylinder plate having a bore, a piston that reciprocates in the bore, a valve plate having a suction hole and a discharge hole facing the bore, and a valve plate equipped with a suction valve and a discharge valve. And a cylinder head that defines a suction chamber communicating with the suction hole and a discharge chamber communicating with the suction hole in cooperation with the cylinder block, and the opening of the suction valve on the valve plate side end peripheral wall of the bore It can be widely applied to a reciprocating compressor in which a locking recess for regulating the above is formed.

It is a fragmentary sectional view of the reciprocating compressor which concerns on the Example of this invention. 1 is a partial structural diagram of a reciprocating compressor according to an embodiment of the present invention. (A) is the II-II arrow directional view of FIG. 1, (b) is sectional drawing along line bb of (a). It is a fragmentary sectional view of a reciprocating compressor when the reciprocating compressor which concerns on the Example of this invention is drive | operated by small capacity | capacitance. It is a fragmentary sectional view of a reciprocating compressor when the reciprocating compressor which concerns on the Example of this invention is drive | operating by large capacity | capacitance.

Explanation of symbols

1 Cylinder Block 5 Cylinder Bore 16 Valve Plate 17 Suction Valve 17a Opening 18 Sub Suction Valve 19 Discharge Valve 20 Locking Recess 20a First Recess 20b Second Recess 21 Suction Valve Escape Step 21a Suction Valve Step 21b Sub Suction Valve Step

Claims (2)

  Formed are a cylinder block formed with a bore, a rotary shaft that is driven to rotate by an external drive source, a piston that reciprocates in the bore following the rotation of the rotary shaft, and a suction hole and a discharge hole that face the bore. A cylinder head that defines a suction chamber communicating with the suction hole and a discharge chamber communicating with the suction hole by sandwiching a valve plate equipped with the suction valve and the discharge valve in cooperation with the cylinder block. A reciprocating compressor in which a locking recess for restricting the opening degree of the suction valve is formed in the peripheral wall on the valve plate side of the bore, and having a smaller diameter than the suction hole facing the suction hole of the valve plate An opening is formed in the suction valve, and includes a sub-suction valve that covers the opening on the side away from the valve plate and contacts the suction valve, the tip of the sub-suction valve is offset from the tip of the suction valve toward the bore center, The locking recess includes a first recess that only the suction valve locks, and a sub suction valve. There reciprocating compressor, characterized in that it is formed in a stepped shape comprising a deeper second recess than the first recess engaged.   The auxiliary suction valve has an outer diameter smaller than the outer diameter of the sealing portion of the suction valve, and the suction valve relief step formed on the end face of the cylinder block is deeper than the suction valve step and the suction valve step. The reciprocating compressor according to claim 1, wherein the reciprocating compressor is formed in a stepped shape including a step.

Images