JPH06147110A - Reciprocating compressor - Google Patents

Abstract

PURPOSE:To maintain sufficient volume efficiency, secure sufficient motive power efficiency and restrain the rise of discharge temperature by interposing a means to energize a rotary valve between a drive shaft and the rotary valve. CONSTITUTION:By rotating a rotary valve 22, refrigerant gas is sucked into respective bores 1C-1E through the lead passages 2C-2E of the bores 1C-1E that are at the suction passage and suction stroke of the rotary valve 22. At this time, even if a high pressure force is acted on seal places opposite to the lead passages 2F, 2A, 2B of the respective bores 1F, 1A, 1B that are in the process of compression/discharge stroke, by means of gas which is being compressed or the remaining gas, openings for slide do not concentrate on the lead passage 2F, 2A, 2B sides of the bores 1F, 1A, 1B that are in the process of compression/discharge stroke, as the rotary valve 22 is energized by means of an energizing means interposed between the drive shaft and the rotary valve 22. As a result, the movement or the like of gas that is being compressed or the remaining gas through the lead passages 2C-2E of the bores 1C-1E that are in the process of suction is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a reciprocating compressor suitable for air conditioning of vehicles.

[0002]

2. Description of the Related Art Conventionally, each piston reciprocates in a plurality of bores formed in a cylinder block in parallel with a drive shaft, such as a swash plate compressor disclosed in Japanese Patent Laid-Open No. 59-145378. A compressor that compresses a refrigerant gas is known. In this type of compressor, a drive shaft is inserted into and supported by a central shaft hole of a cylinder block, and each piston is linearly moved in each bore by being linked to a swash plate in a crank chamber that cooperates with the drive shaft. A housing is joined to the end surface of the cylinder block via a valve plate, and a suction chamber for supplying the refrigerant gas into the bore and a discharge chamber for discharging the refrigerant gas compressed by the piston in the bore are provided in the housing. Has been formed. The suction of the refrigerant gas from the suction chamber into the bore is performed by moving the piston to the bottom dead center position, and the suction port formed in the valve plate and the pressure inside the bore provided on the bore side of the suction port. And an intake valve that opens the intake port accordingly. Further, the discharge of the refrigerant gas from the inside of the bore to the discharge chamber is performed by moving the piston to the top dead center position, and the discharge port formed on the valve plate and the discharge chamber side of this discharge port are provided inside the bore. And a discharge valve that opens the discharge port in response to pressure.

[0003]

However, in the conventional compressor, since the suction valve is constructed so as to overcome the elastic force of its own acting in the direction of maintaining the closed state to open the valve, the pressure loss is reduced. Is big. This pressure loss leads to deterioration of volumetric efficiency. Therefore, the present applicant has filed Japanese Patent Application No. 3-
No. 229166 proposed a reciprocating compressor with excellent volume efficiency. In this compressor, a conduction path that radially communicates each bore and the central shaft hole is formed, and a rotary valve is coupled to the drive shaft so as to be synchronously rotatable. The rotary valve is formed with an intake passage that sequentially connects the passage of each bore in the intake stroke and the intake chamber.

In the proposed compressor, the rotary valve rotates in synchronization with the drive shaft, so that the refrigerant gas in the suction chamber is sequentially sucked into each bore, and the suction action of the refrigerant gas is smooth and stable in each bore. As a result, the pressure loss is extremely reduced. Thus, this compressor can maintain sufficient volume efficiency. However, in this compressor, as shown in, for example, FIG. 6, a high pressure due to the gas being compressed or the residual gas of the piston head is applied to the seal portion facing the passages 2F, 2B, 2A of the bores in the compression / discharge stroke. P is working. Therefore, the rotary valve 91, which is slidably rotatable in the central shaft hole 90a, has the passages 2F, 2A for the bores in the compression stroke and the passages 2 for the bores in the discharge stroke.
Displacement from the B side to the side of the bores 2C to 2E on the suction stroke, and the gap C for sliding is concentrated on the sides of the bores 2F, 2B, 2A on the bores on the compression / discharge strokes. Therefore, the gas being compressed or the residual gas moves through the gap C into the passages 2C to 2E of the bore in the suction stroke, and from both end surfaces of the rotary valve 91 to the crank chamber or the central shaft hole 90a.
It also moves to the suction chamber that communicates with. Reference numeral 91a is an intake passage. For this reason, the power efficiency is lowered, and the already hot gas is re-compressed to be further heated, so that the discharge temperature is increased and the capacity of the air conditioner is lowered.

An object of the present invention is to maintain a sufficient volume efficiency, secure a sufficient power efficiency, and suppress an increase in discharge temperature.

[0006]

In order to solve the above-mentioned problems, a reciprocating compressor of the present invention has a cylinder block having a plurality of bores around its axis, and is fitted into a central shaft hole of the cylinder block. A reciprocating compressor including a supported drive shaft and a piston that is linearly moved in the bore by being linked to a swash plate in a crank chamber that cooperates with the drive shaft. And a radial conduction path connecting the two with each other, and a rotary valve having a suction passage for sequentially connecting the suction passage and the conduction path of each bore in the suction stroke is coupled to the drive shaft in a synchronously rotatable manner. In addition, a novel structure is adopted in which a biasing means for biasing the rotary valve toward the bore of the bore during the compression / discharge stroke is interposed between the drive shaft and the rotary valve.

[0007]

In the reciprocating compressor of the present invention, the rotary valve rotates in synchronization with the drive shaft, so that the refrigerant gas in the suction chamber passes through the suction passage of the rotary valve and the passage of each bore in the suction stroke. Are sequentially sucked into the respective bores, and the suction action of the refrigerant gas is smoothly and stably continued in the respective bores, so that the pressure loss is extremely reduced.

At this time, the rotary valve is interposed between the rotary shaft and the drive shaft even if a high pressure is applied to the seal portion facing the passage of each bore in the compression / discharge stroke by the gas being compressed or the residual gas. Since the urging means biases the bore of the bore during the compression / discharge stroke, the clearance for sliding is not concentrated on the side of the bore of the bore in the compression / discharge stroke. Therefore, the gas under compression or the residual gas moves through the gap into the passage of the bore in the suction stroke, or from both end faces of the rotary valve to the suction chamber communicating with the crank chamber or the central shaft hole. Is prevented.

[0009]

Embodiments 1 and 2 embodying the present invention will be described below with reference to the drawings. (Embodiment 1) In FIGS. 1 and 2, reference numeral 1 is a cylinder block having a central axial hole 1a penetrating in the axial direction and six bores 1A to 1F. One end surface of the cylinder block 1 is a front housing. 2 is joined, and the rear housing 4 is joined to the other end surface via a ring-shaped valve plate 3. In the crank chamber 5 in the front housing 2,
The drive shaft 6 is fitted in the front housing 2 and the central shaft hole 1a of the cylinder block 1 and is rotatably supported. A rotor 7 is fixed on the drive shaft 6, and a long hole 8a is formed at the tip of a support arm 8 extending to the rear surface side of the rotor 7. A pin 8b is slidably fitted in the long hole 8a, and a swash plate 9 is tiltably connected to the pin 8b.

A sleeve 10 is loosely fitted on the drive shaft 6 adjacent to the rear end of the rotor 7, is constantly biased toward the rotor 7 by a coil spring 11, and is provided on both left and right sides of the sleeve 10. A pivot 10a (only one of which is shown) is fitted into an engagement hole (not shown) of the swash plate 9, and the swash plate 9 is supported so as to be able to swing around the pivot 10a. A swing plate 12 is supported on the rear surface side of the swash plate 9 via a thrust bearing or the like,
Rotation of the oscillating plate 12 is restricted by notches (not shown). Further, six connecting rods 14 are moored to the outer edge of the oscillating plate 12 at equal intervals, and each connecting rod 14 has a bore 1A to.
It is moored with the piston 15 in 1F. Therefore,
The rotary motion of the drive shaft 4 is converted into the back-and-forth swing of the rocking plate 12 by the intervention of the rotor 7 and the swash plate 9, each piston 15 reciprocates in the bores 1A to 1F, and the pressure in the crank chamber 5 changes. The stroke of the piston 15 and the tilt angle of the oscillating plate 12 change according to the pressure difference from the suction pressure. The pressure in the crank chamber 5 is controlled based on the cooling load by a control valve (not shown) mounted in the rear housing 4.

The rear housing 4 is provided with a suction chamber 17 which is open at the rear end face in the center and communicates with the central shaft hole 1a of the cylinder block 1. A discharge chamber 18 is provided outside the suction chamber 17. Are formed. Valve plate 3
Is a discharge port 3 that communicates with the head of each bore 1A-1F.
a is penetratingly provided, and a retainer 21 is sandwiched via a discharge valve 20 on the discharge chamber 18 side of each discharge port 3a.

As shown in FIG. 2, the cylinder block 1 also has radial passages 2A to 2F formed between the bores 1A to 1F and the central shaft hole 1a. At the tip of the drive shaft 6 extending into the central shaft hole 1a, a cylindrical rotary valve 22 that slides with the central shaft hole 1a is mounted, and the rear side of the rotary valve 22 is provided with a thrust bearing and a disc spring. It is supported on the inner wall of the suction chamber 17 via the.

As shown in FIG. 3, the rotary valve 22 extends in the axial direction from the center of the axial center on the suction chamber 17 side, and has a PTFE formed with a suction passage 25 that opens at a predetermined angle on the outer peripheral surface.
Made rotary valve body 23 and the crank chamber 5 of the rotary valve body 23
And a connecting member 24 which is press-fitted to the side and fixed by a nut with a seat at the bottom surface of the suction passage 25. The connecting member 24 is formed with a rectangular parallelepiped connecting concave portion 24a, and a rectangular parallelepiped connecting convex portion 6a protruding from the tip of the drive shaft 6 is non-rotatably engaged with the connecting concave portion 24a. . Seating surfaces that face each other are formed on the coupling recess 24a and the coupling projection 6a, and a coil spring 26 as a biasing member is interposed between these bearing surfaces. As shown in FIG. 4, the urging force F of the coil spring 26 is set at the center of the opening angle of the suction passage 25 in the symmetrical direction, and the high pressure acting on the rotary valve 22 by the gas being compressed or the residual gas of the piston head. It is set larger than P.

The compressor configured as described above is arranged in its circuit as a vehicle air-conditioning refrigerating device and used. When this compressor is operated and the drive shaft 6 shown in FIG. 1 rotates, the swash plate 9 swings while rotating together with the drive shaft 6, and the swing plate 12 is restricted from rotating with respect to the swash plate 9. The oscillating motion is performed only by the above, and thereby the piston 15 reciprocates in the bores 1A to 1F. Then, when the piston 15 starts moving from the top dead center to the bottom dead center in the bores 1A to 1F, the bores 1A to 1F enter the suction stroke. Further, when the piston 15 starts moving from the bottom dead center to the top dead center within the bores 1A to 1F, the bores 1A to 1F enter the compression / discharge stroke.

Here, as shown in FIG. 2, when the rotary valve 22 rotates in the direction of the arrow in synchronism with the drive shaft 6, for example, at the stage shown in the same figure, the bore 1C in the intake stroke. 1E, the passages 2C to 2E communicate with the suction passage 25, and the refrigerant gas in the suction chamber 17 is sucked into the suction passage 25.
The air is sequentially sucked into the bores 1C to 1E via the conduction paths 2C to 2E. On the other hand, in the bores 1F and 1A in the compression stroke, their conduction paths 2F and 2A do not communicate with the suction passage 25,
The rotary valve 22 is closed by the seal portion. At this time, the pressure in the bores 1F, 1A is still lower than the pressure in the discharge chamber 18, and the discharge valve 20 is closed. Further, the bore 1B in the discharge stroke also has its conduction path 2B not in communication with the suction path 25, and is closed by the sealing portion of the rotary valve 22. However, at this time, the pressure in the bore 1B becomes higher than the pressure in the discharge chamber 18, and the discharge valve 20 is opened.

After that, when the rotary valve 2 rotates, the bore 1B
Ends the discharge stroke and shifts to the suction stroke, and the bore 1E ends the suction stroke and enters the compression stroke. In this manner, the bores 1A to 1F sequentially repeat the suction, compression, and discharge strokes via the rotary valve 22 that rotates in synchronization with the reciprocating motion of the piston 15. At this time, the bores 1A to 1F in the suction stroke are communicated with the suction chamber 17 via the communication passages 2A to 2F and the suction passage 25, and the suction action of the refrigerant gas is continued smoothly and stably. Is made extremely small.

At this time, for example, as shown in FIG. 4, at the sealing portion of each of the bores 1F, 1A, 1B in the compression / discharge stroke, which faces the conduction paths 2F, 2A, 2B, the gas under compression or the residual gas is compressed. Causes a high pressure P to act. However,
The rotary valve 22 is urged by the urging force F of the coil spring 26 toward the center of the intake passage 25 in the symmetrical direction of the opening angle, and the urging force F is larger than the high pressure P.
= F ′ is displaced toward the conduction path 2A side of the bore 1A at the end of compression. Therefore, the clearance C for sliding the rotary valve 22 is equal to the conduction path 2C of the bores 1C to 1E in the suction stroke.
Concentrated to ~ 2E, each bore 1 in compression / discharge stroke
The rotary valve 2 is provided on the F, 1A, 1B conduction paths 2F, 2A, 2B side.
It is preferably sealed by two sealing parts. For this reason, the gas being compressed or the residual gas is discharged from the bore 1 in the suction stroke.
It is possible to prevent the movement to the inside of the conduction paths 2C to 2E of C to 1E and the movement from the both end surfaces of the rotary valve 22 to the crank chamber 5 or the suction chamber 17.

Therefore, in this compressor, while maintaining sufficient volume efficiency, it is possible to prevent a reduction in power efficiency, and there is no need to re-compress already hot gas to further raise the temperature. It is possible to suppress the temperature rise and maintain the capacity of the air conditioner. (Embodiment 2) In this compressor, as shown in FIG. 5, the difference F ′ between the urging force F of the coil spring 26 and the high pressure P due to the gas being compressed or the residual gas causes the rotation of the opening angle of the suction passage 25. It is set slightly ahead of the direction start point. Since the other configurations are the same as those of the compressor of the first embodiment, detailed description will be omitted.

Strictly speaking, in this compressor, for example, the passage 2B of the bore 1B in the discharge stroke presses the rotary valve 22 with the discharge pressure, and the passages 2F, 2A of the bores 1F, 1A in the compression stroke are compressed. Since the rotary valve 22 is pressed by the pressure and the discharge pressure is higher than the compression pressure, the high pressure P is directed to the conduction path 2B side. Even in such a case, in this compressor, since the rotary valve 22 is displaced to the side of the communication path 2B of the bore 1B during the discharge stroke by the force F ′, the bore that is most required to prevent leakage during the discharge stroke. The conductive path 2B of 1B is preferably sealed. Therefore, in this compressor, it is possible to prevent the power efficiency from lowering more than the compressor of the first embodiment, and it is possible to suppress the rise in the discharge temperature.

[0020]

As described above in detail, since the reciprocating compressor of the present invention has the structure described in the claims, it is possible to maintain the sufficient volume efficiency and reduce the power efficiency. In addition to being able to prevent it, the already hot gas is not recompressed and further heated, so that it is possible to suppress the rise of the discharge temperature and maintain the capacity of the air conditioner.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a compressor according to a first embodiment.

FIG. 2 is a cross-sectional view of the compressor according to the first embodiment.

FIG. 3 is a cross-sectional view of a rotary valve according to the compressor of the first embodiment.

FIG. 4 is a schematic diagram showing a relationship between a rotary valve and a conduction path according to the compressor of the first embodiment.

FIG. 5 is a schematic diagram showing a relationship between a rotary valve and a conduction path according to the compressor of the second embodiment.

FIG. 6 is a schematic diagram showing a relationship between a rotary valve and a conduction path according to the previously proposed compressor.

[Explanation of symbols]

1 ... Cylinder block 1a ... Central shaft hole 1A
~ 1F ... Bore 3 ... Valve plate 4 ... Rear housing 6 ...
Drive shaft 5 ... Crank chamber 9 ... Swash plate 15
... Piston 17 ... Suction chamber 18 ... Discharge chamber 2A
2F ... conduction path 22 ... rotary valve 25 ... suction path 26
… Coil spring

Claims (1)

[Claims] 1. A cylinder block having a plurality of bores around an axis, a drive shaft fitted and supported in a central shaft hole of the cylinder block, and a swash plate in a crank chamber cooperating with the drive shaft. In the reciprocating compressor having a piston that is linearly moved in the bore, a radial conduction path that connects the bore and the central shaft hole is formed between the bore and the drive shaft. A rotary valve having a suction passage that sequentially connects the suction passage and the passage of each bore in the suction stroke is connected so as to be rotatable synchronously, and the rotary valve is compressed and discharged between the drive shaft and the rotary valve. A reciprocating compressor, characterized in that an urging means for urging the bore in the stroke is provided on the side of the conduction path.