JP2797496B2 - Swash plate compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is located in a cylinder block in which front and rear housings are joined at both front and rear ends in a state facing a swash plate chamber and front and rear sides of the swash plate chamber. A cylinder bore is formed, and a piston performing a compression action on the front and rear sides is reciprocally accommodated in the cylinder bore, and the piston is provided via a swash plate mounted on a drive shaft rotatably supported by a cylinder block. The present invention relates to a swash plate type compressor which is driven reciprocally.

2. Description of the Related Art In a swash plate compressor of this type, a radial bearing for supporting a drive shaft, a thrust bearing, and lubrication of a sliding portion such as a shoe or a piston for transmitting a swinging motion of a swash plate to a piston as a reciprocating motion. Is contained in the refrigerant gas in the form of mist. When the refrigerant gas compressed inside the compressor is discharged and circulated to the external cooling circuit, when the mist-like oil is discharged and circulated to the cooling circuit, the oil is deposited on the inner wall of the evaporator in the cooling circuit. Adhesion hinders heat exchange. Therefore, conventionally, there has been proposed a compressor configured to separate lubricating oil contained in a refrigerant gas from a refrigerant gas at a high pressure portion of the compressor and return the separated oil to a low pressure portion of the compressor. I have. In this type of compressor, refrigerant gas containing oil flows from a discharge hole of the compressor,
The oil is guided through a discharge passage into an expansion chamber (volume chamber) formed by swelling in the compressor casing, and oil is separated and accumulated in the oil storage chamber while entering the service flange on the discharge side. Then, the oil stored in the oil storage chamber is returned to a low-pressure section such as a swash plate chamber through an oil return passage.

Japanese Patent Application Laid-Open No. 55-69778 discloses a swash plate chamber 64 separated from an oil separation chamber 63 in cylinders 61 and 62 as shown in FIG. And the oil separation chamber, which communicates with the suction chambers 65a and 65b communicating with the suction side of
An introduction hole 67 communicating with the oil separation chamber 63 is provided, and a part of the refrigerant gas flowing into the oil separation chamber 63 is configured to be blown to the thrust bearing 66 through the introduction hole 67, and is separated in the oil separation chamber 63. Oil passes through hole 68 and radial bearing 69
Is supplied to the oil reservoirs 71a and 71b through the holes 70, and flows into the swash plate chamber 64 through the small holes 72a and 72b.

[Problems to be Solved by the Invention] However, in a configuration in which oil is separated from the refrigerant gas on the high pressure side (discharge side) of the compressor, the separated oil has a high temperature because the discharge gas has a high temperature. As the oil is returned to the low pressure side (swash plate chamber), not only does the viscosity of the oil decrease and the lubrication characteristics deteriorate, but also a film is formed on the sliding surface between the cylinder bore and the piston to keep the compression chamber in a sealed state. Ability also decreases.

Also, since the oil content of the discharge gas is smaller than the oil content of the suction gas, the amount of oil separated and stored is small, and the discharge gas leaks to the low pressure side depending on the operating conditions, causing a decrease in volumetric efficiency or an increase in oil temperature. In addition, poor lubrication occurs due to the oil adhering to the shoes and the like being blown off by the leak gas. For example, during normal operation of the compressor, the pressure of the discharged gas is 14 to 15 atm.However, when the cooling load is large, such as during traffic congestion in summer, or when the cooling of the condenser becomes insufficient, the maximum pressure is 30 atm. Reach When the discharge pressure increases, the pressure in the expansion chamber (volume chamber) also increases, and the oil stored in the oil storage chamber is returned to the low-pressure section of the compressor more than necessary, and as a result, the oil in the oil storage chamber runs out. A state occurs, and a part of the discharge gas leaks from the oil return passage to the low pressure side of the compressor.
In addition, during low-speed operation, since the amount of refrigerant gas discharged is small, the amount of separated oil is also small, and leakage of discharged gas from the oil return passage occurs. Furthermore, a leak may occur during the intermittent operation.

On the other hand, in the case of the compressor disclosed in JP-A-55-69778, oil is separated from the refrigerant gas before the return refrigerant gas is introduced into the compression chamber. Is returned to the swash plate chamber 64 in a low state. However, most of the returned refrigerant gas does not pass through the swash plate
Is introduced into the suction chambers 65a and 65b through the passages 73a and 73b, so that there is not much cooling effect of the returned refrigerant gas on the swash plate chamber 64. Therefore, the temperature inside the swash plate chamber 64 increases due to the influence of the compression heat accompanying the operation of the compressor, and the viscosity of the oil decreases to deteriorate the lubrication characteristics. In addition, a coating is formed on the sliding surface between the cylinder bore and the piston. Also, the ability to form and maintain the compression chamber in a sealed state is reduced, and the refrigerant gas leaks from the swash plate chamber 64 into the compression chamber during suction, and the suction amount of the refrigerant gas is reduced by that amount, thereby lowering the compression efficiency. is there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and its object is not to be influenced by the operation state of the compressor, and a swash plate compressor capable of always maintaining good lubrication of a sliding portion. Is to provide.

[Means for Solving the Problems] In order to achieve the above object, according to the present invention, a swash plate chamber is opposed to a cylinder block having front and rear housings joined to both front and rear ends, and the front and rear sides of the swash plate chamber are opposed to each other. A cylinder bore positioned in a state is formed, and a piston performing a compression action on the front and rear sides is housed in the cylinder bore in a reciprocating manner, and the piston is mounted on a drive shaft rotatably supported by a cylinder block. In a swash plate compressor reciprocatingly driven through a swash plate,
The cylinder block is provided with a return refrigerant gas suction port that opens to the swash plate chamber, an oil separation section is provided between the swash plate chamber and the compression chamber, and a return passage for returning the oil separated by the oil separation section to the swash plate chamber. It was provided so that the lower part of the oil separation part and the swash plate chamber could be in direct communication.

[Operation] When the compressor of the present invention is operated, the entire amount of the refrigerant gas returned from the external cooling circuit to the compressor is first introduced into the swash plate chamber. The refrigerant gas that has entered the swash plate chamber is introduced into the compression chamber from the suction chamber through an oil separation unit provided between the swash plate chamber and the compression chamber, and after compression is supplied to the external cooling circuit through the discharge chamber. You. The entire amount of the low-temperature return refrigerant gas is first introduced into the swash plate chamber to cool the swash plate chamber and each sliding portion, thereby maintaining good lubrication characteristics of oil and preventing seizure of the driving portion. . Further, when the refrigerant gas passes through the oil separation unit, mist-like oil contained in the refrigerant gas is separated, and the separated oil is returned to the lower passage of the oil separation unit and the swash plate chamber directly. Is returned to the swash plate room. Since the oil is separated before the refrigerant gas is compressed, that is, before the temperature of the refrigerant gas becomes high, the oil is returned to the swash plate chamber with a low temperature and good lubrication characteristics.

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a combination of the front and rear housing portions and the cylinder block portion that are broken at different positions (the same applies to another embodiment).

As shown in FIG. 1, both end portions of cylinder blocks 1 and 2 opposed to each other are closed by front and rear housings 5 and 6 via valve plates 3 and 4, respectively. Fixed. A swash plate chamber 8 is formed in a joint portion between the cylinder blocks 1 and 2, and the swash plate chamber 8 is rotatable through radial bearings 9 in shaft holes 1 a and 2 a provided through the centers of the cylinder blocks 1 and 2. The swash plate 11 is housed in a state fitted on the supported drive shaft 10. As shown in FIGS. 1 and 2, five pairs of cylinder bores 12 are formed in the cylinder blocks 1 and 2 at radial positions parallel to the drive shaft 10 and about the drive shaft 10.
Each of the cylinder bores 12 accommodates a two-headed piston 13 so as to be slidable. Each piston 13 is connected to a swash plate 11 via a shoe 14.
, And is reciprocated in the cylinder bore 12 by the swing of the swash plate 11 accompanying the rotation of the drive shaft 10 to perform a compression operation. A thrust bearing 15 is interposed between both ends of the boss 11a of the swash plate 11 and the cylinder blocks 1 and 2.

As shown in FIG. 2, suction chambers 16 and 17 are formed in the front and rear housings 5 and 6 on the center side, and discharge chambers 18 and 19 are formed on the outer peripheral side. In addition, a suction port 20 and a discharge port 22 are formed in both valve plates 3 and 4, respectively. Further, suction valves 24 are provided on the cylinder blocks 1 and 2 sides of the valve plates 3 and 4, and the valve plates 3 and 4 are provided.
A discharge valve 26 is provided on the housing 5, 6 side.

As shown in FIG. 3, the side of the rear cylinder block 2 is provided with a gas serving as a suction port opening to the swash plate chamber 8 for introducing the entire amount of refrigerant gas G returned from the external cooling circuit into the swash plate chamber 8. An inlet 28 is formed. As shown in FIGS. 1 and 3, lubricating oil contained in a mist form is introduced from the refrigerant gas introduced from the swash plate chamber 8 into the suction chambers 16 and 17 at the upper part of the rear cylinder block 2. An oil separating section 29 for separating is provided. That is, a separation chamber 30 whose upper part is opened is formed at the upper part of the rear cylinder block 2, and is covered with the lid 31 in an airtight state. In the center of the lower part of the separation chamber 30, a cylindrical part 32 having a passage 32a communicating the swash plate chamber 8 and the separation chamber 30 is provided so as to project therefrom.
Outside, a return passage 33 is formed at a position substantially corresponding to the center of the swash plate chamber 8. On the other hand, an annular guide plate 34 is formed on the lower surface of the lid 31 so as to extend from the tip of the cylindrical portion 32 to a position below the cylindrical portion 32 and to have a gap with the outer peripheral surface of the cylindrical portion 32. Have been. Also, cylinder blocks 1 and 2
Has one end above the suction chambers 16 and 17 and the other end
The suction passages 36, 36 communicating with the upper part of the are formed respectively.

As shown in FIG. 3, a gas outlet 37 connected to an external cooling circuit (not shown) is formed in the lid 31, and a chamber is provided in the rear cylinder block 2 at a position corresponding to the gas outlet 37.
38 are formed. The chamber 38 and the two discharge chambers 18, 1
9 is communicated via a discharge passage 39, and the discharge gas discharged to the discharge chambers 18 and 19 is supplied to the external cooling circuit via the discharge passage 39, the chamber 38, and the gas outlet 37.

 Next, the operation of the device configured as described above will be described.

Now, when the swash plate 11 is rotated by the rotation of the drive shaft 10,
Each piston 13 is reciprocated in the left-right direction in FIG. 1 within the cylinder bore 12, and suction, compression and discharge of the refrigerant gas are performed. The entire amount of the refrigerant gas returned from the external cooling circuit to the compressor is introduced into the swash plate chamber 8 from the gas inlet 28. The refrigerant gas introduced into the swash plate chamber 8 flows upward through the passage 32a and is discharged into the separation chamber 30.
Then, the air flows in the downward direction along the inner surface of the guide wall 34, and flows upward along the wall surface of the separation chamber 30, and is supplied to the suction chambers 16 and 17 via the suction passages 35 and 36.

The refrigerant gas discharged from the swash plate chamber 8 to the separation chamber 30 contains a large amount of mist-like oil, but is discharged into the separation chamber 30 from the passage 32a and hits the lid 31 to change its flow direction. When converted, mist-like oil O in the refrigerant gas
Adheres to the lid 31 and is separated. Then, the separated oil O is dripped and stored at the bottom of the separation chamber 30 along the guide wall 34, is supplied to the swash plate chamber 8 through the return passage 33, and is moved by the piston 13, the shoe 14, the thrust bearing 15, and the like. Used for lubrication of parts.

After the refrigerant gas is subjected to the compressing action, its temperature rises, so that the temperature of the dispersed oil O also rises and its lubricating properties deteriorate, but as described above, the refrigerant gas exits the swash plate chamber 8 and O is separated, so the separated oil O
Does not rise to such an extent that its lubrication characteristics deteriorate, and the oil O returned from the separation chamber 30 to the swash plate chamber 8 smoothly lubricates the movable part. Further, since the oil O contained in the refrigerant gas that has exited the swash plate chamber 8 is immediately separated and collected and returned to the swash plate chamber 8, even if the compressor is operated with the flow rate of the return refrigerant gas being small, lubrication is maintained. The required oil amount is secured.

In addition, since the entire amount of the low-temperature refrigerant gas returned from the external cooling circuit is introduced into the swash plate chamber 8, the inside of the swash plate chamber 8 is cooled, and the oil temperature in the swash plate chamber 8 is reduced to lubricate each part with the oil O. Is performed satisfactorily, and the sliding portion is cooled, so that seizure of the sliding portion is reliably prevented.

Second Embodiment Next, a second embodiment will be described with reference to FIG. In this embodiment, only the configuration of the oil separating section 29 is different from that of the previous embodiment. Note that the same parts as those in the above embodiment are denoted by the same reference numerals and described. A guide member 40 surrounding the cylindrical portion 32 is provided in the separation chamber 30. Guide member 40 is cylindrical
40a and a funnel-shaped oil return portion 40b formed inside the upper portion of the cylindrical portion 40a.
Is fitted on the bottom surface. An oil reservoir 41 is formed between the inner surface of the cylindrical portion 40a and the outer surface of the cylindrical portion 32, and a return passage 33 is formed on the bottom surface of the oil reservoir 41. The oil return portion 40b is slightly inserted into the tubular portion 32 with its lower end having a slight gap with the tip of the tubular portion 32.
An annular ridge 42 having a diameter larger than that of the cylindrical portion 32 and smaller than that of the cylindrical portion 40a is provided on the lower surface of the lid 31 so that the center thereof coincides with the center of the cylindrical portion 32.

Also in the apparatus of this embodiment, the refrigerant gas is discharged from the swash plate chamber 8 into the separation chamber 30 through the passage 32a of the cylindrical portion 32.
When the refrigerant gas passes through the passage 32a, part of the oil O contained in the mist in the refrigerant gas is attached to the inner wall of the tubular portion 32, and the oil O attached to the inner wall is gradually reduced by the refrigerant gas flow. It moves toward the tip of the shape part 32. And the cylindrical part
The oil O that has moved to the tip of 32 is picked up by the oil return portion 40b and the lower surface of the oil return portion 40b and the cylindrical portion 40a.
Along the inner surface of the swash plate 8 and is returned to the swash plate chamber 8 from the return passage 33. Further, the refrigerant gas having passed through the oil return portion 40b collides with the lid 31 and changes its direction in the same manner as in the previous embodiment, and is guided by the annular ridge 42 and the guide member 40 to be sucked through the suction passages 35 and 36. It is supplied to the chambers 16 and 17. When the refrigerant gas collides with the lid 31, the mist-like oil O contained in the refrigerant gas adheres to the lid 31 and the annular ridge 42 and is separated and collected, and the separated oil O is placed on the oil return portion 40b. And falls along the oil return portion 40b from the passage 32a into the swash plate chamber 8.

In the case of this embodiment, the oil adhering to the inner wall surface of the cylindrical portion 32 is reliably recovered as compared with the device of the previous embodiment, and the oil reservoir 41 is provided with the openings of the suction passages 36, 36. Is completely separated from the oil, the oil O separated and recovered is not supplied to the suction chambers 16 and 17 via the suction passages 35 and 36.

Third Embodiment Next, a third embodiment will be described with reference to FIGS. Above the rear cylinder block 2, there is formed a separation chamber 43 extending in the front-rear direction and having a circular cross section with the front cylinder block 1 side opened. A guide cylinder 44 projects from the rear housing 6 side end of the separation chamber 43, and a guide cylinder 45 projecting into the separation chamber 43 is formed on an end surface of the front cylinder block 1 at a position opposed to the guide cylinder 44. Have been. Each guide tube 44, 45 is communicated with the suction passages 35, 36. A passage 46 for discharging the refrigerant gas in the swash plate chamber 8 to the separation chamber 43
As shown in FIG. 6, is formed so as to open in an eccentric state with respect to the separation chamber 43. A return passage 33 is formed at the bottom of the separation chamber 43 at a position corresponding to the swash plate chamber 8.

In the apparatus of this embodiment, since the opening of the passage 46 is eccentric with respect to the separation chamber 43, the refrigerant gas discharged into the separation chamber 43 from the swash plate chamber 8 through the passage 46 is swirled in the separation chamber 43. It becomes a flow. Then, the mist-like oil O having a large specific gravity and a high viscosity becomes a flow moving along the wall surface of the separation chamber 43 as shown by a broken line, and the oil O adheres to the wall surface and is separated from the refrigerant gas. Oil O adhering to the wall surface accumulates at the bottom of the separation chamber 43 along the wall surface and returns from the return passage 33 to the swash plate chamber 8.
Will be returned within. On the other hand, the refrigerant gas having a low specific gravity and a low viscosity collects near the center of the separation chamber 43 as shown by a dashed line, and is guided from the guide cylinders 44, 45 to the suction passages 35, 36 to be drawn into the suction chambers 16, 1.
Supplied to 7.

Fourth Embodiment Next, a fourth embodiment will be described with reference to FIGS. A drive shaft is provided above the swash plate chamber 8 in the rear cylinder block 2.
A passage 47 is formed extending in a substantially arc shape in a plane orthogonal to 10 and having both ends communicating with the swash plate chamber 8.
Above the passage 47, a communication passage 4 communicating with the suction passages 35 and 36 is provided.
8 is formed to be orthogonal to the passage 47. As shown in FIG. 7, an accommodating portion 49 extending in the width direction is formed substantially at the center of the passage 47, and a T-shaped guide pipe 50 is provided in the accommodating portion 49. And is arranged in a state of being orthogonal to the passage 47 in a state where the passage 47 is communicated. A return passage 33 is formed at the bottom of the housing 49.

Then, the refrigerant gas in the swash plate chamber 8 is guided from both sides of the passage 47 to the housing portion 49 and collides with the outer peripheral surface of the guide pipe 50 disposed in the housing portion 49 at right angles to the passage 47. Due to this collision, mist-like oil O contained in the refrigerant gas adheres to the outer peripheral surface of the guide pipe 50 and is separated. After the separated oil O accumulates at the bottom of the accommodating portion 49, the swash plate chamber is returned from the return passage 33. Returned to 8. The refrigerant gas from which the oil O has been separated is guided into the guide pipe 50 while changing the flow direction, and is supplied to the suction chambers 16 and 17 via the communication passage 48 and the suction passages 36 and 36.

In this embodiment, a guide pipe in which refrigerant gas containing mist-like oil O is disposed in a state orthogonal to the flow thereof
After colliding with 50, it is guided into the guide pipe 50, so that the oil separating action is improved as compared with the first embodiment.

Fifth Embodiment Next, a fifth embodiment will be described with reference to FIGS. In each of the above embodiments, the oil separating section 29 is provided above the rear cylinder block 2 so that the refrigerant gas is supplied to the suction chambers 16 and 17.
The oil O is separated and recovered before the oil is supplied to the suction chamber. In this embodiment, the oil separation portions 29 are provided in the front housing 5 and the rear housing 6, respectively.
The point that the oil O is separated and recovered at 16, 17 is greatly different from the above embodiments.

Front housing 5 and rear housing 6 are suction chambers
In order to increase the volume of 16, 17, the length is formed long. Each of the valve plates 3 and 4 has a substantially lower half formed at a portion corresponding to the suction chambers 16 and 17, and the thick portion has one end provided with a cylinder bore 12 provided at a lower side of the compressor. A suction introduction passage 51 communicating with the openings 20 and 21 and having the other end opened at the upper end of the thick portion is formed. Cylinder block
As shown in FIGS. 9 and 10, three suction passages 52 and 53 for communicating the swash plate chamber 8 and the suction chambers 16 and 17 are provided around the drive shaft 10 at the center of the drive shaft 10. Formed at the position
The suction chambers 16 and 17 are located at positions corresponding to the lower ends of the suction chambers 16 and 17.
In order to return the oil O accumulated therein to the swash plate chamber 8, return passages 54, 55 having a smaller diameter than the suction passages 52, 53 are formed.

A gas inlet 28 for introducing the refrigerant gas returned from the external cooling circuit to the compressor into the swash plate chamber 8 is formed above the rear cylinder block 2.

In the compressor of this embodiment, a refrigerant gas is introduced into the swash plate chamber 8 from a gas inlet 28 formed in the upper part of the swash plate chamber 8. When the swash plate 11 is rotated by the rotation of the drive shaft 10, the pistons 13 are reciprocated in the cylinder bore 12 in the left-right direction in FIG. 9 to suck, compress, and discharge the refrigerant gas. The refrigerant gas in the swash plate chamber 8 is discharged into the suction chambers 16 and 17 through the suction passages 52 and 53, and is drawn into the compression chambers Pf and Pr from the suction ports 20 and 21 with the opening and closing of the suction valves 24 and 25. Compression chamber P
After being compressed by f and Pr, discharge port 2 is opened and closed by opening and closing discharge valves 26 and 27.
Discharge from the discharge chambers 18 and 19 from the discharge chambers 2 and 23.

When the refrigerant gas is discharged into the suction chambers 16 and 17 through the suction passages 52 and 53, the flow rate of the refrigerant gas becomes slower, and the oil O contained in the refrigerant gas has a specific gravity as compared with the refrigerant gas. Mist oil O contained in refrigerant gas
Is separated from the flow of the refrigerant gas shown by the dashed line in FIG. 9 and accumulates in the lower portions of the suction chambers 16 and 17. The accumulated oil O is returned to the swash plate chamber 8 through the return passages 54 and 55. The positions of the two cylinder bores 12 provided below the cylinder blocks 1 and 2 are substantially the same as the level of the oil O accumulated in the lower portions of the suction chambers 16 and 17, but the suction holes corresponding to the two cylinder bores 12 are provided. Open ends of mouths 20 and 21 are suction chamber 1.
The oil O accumulated in the lower part of the suction chambers 16 and 17 flows from the suction ports 20 and 21 into the compression chambers Pf and Pr because the oil O is communicated with the suction introduction passage 51 provided at a height substantially at the center of the cylinders 6 and 17. Will not be inhaled.

In this embodiment, since the oil O is separated from the refrigerant gas in the suction chambers 16 and 17, the oil is also supplied to the shaft seal 56 provided in the suction chamber 16 on the front side.

Embodiment 6 Next, a sixth embodiment will be described with reference to FIGS. Also in this embodiment, the oil separating section 29 is provided in the front housing 5 and the rear housing 6,
6, 17 are divided into two chambers 16a, 16b, 17a, 1
7b, and oil is separated and collected from the refrigerant gas in each of the chambers 16a, 16b, 17a, and 17b.
The chambers 16a, 16b, 17a, 17b are communicated by through holes 57a, 58a formed in the center of the partition walls 57, 58. Further, near the center of the cylinder blocks 1 and 2, five suction passages 52 and 53 are formed at positions centered on the drive shaft 10, and the respective partition walls 57 and 58 are formed.
Are formed with cylindrical portions 57b, 58b each having one end connected to the suction passages 52, 53 and communicating the swash plate chamber 8 with one of the chambers 16a, 17a remote from the valve plates 3, 4. At positions corresponding to the lower ends of the suction chambers 16 and 17 of the cylinder blocks 1 and 2, the two valve plates 3 and 4 and the two partition walls 57 and 58, the oil O accumulated in the suction chambers 16 and 17 is transferred to the swash plate chamber 8. Return passage 54,5 for return
5 are formed.

In this embodiment, the refrigerant gas in the swash plate chamber 8 is
2, 53 and one of the suction chambers 16, 17 through the cylinders 57b, 58b.
The mist-like oil O having a high specific gravity contained in the refrigerant gas is separated into the mist-like oil O contained in the refrigerant gas and falls to the lower part of one of the chambers 16a, 17a as shown by a broken line in FIG. Further, when the flow of the refrigerant gas collides with the wall surface of one of the chambers 16a, 17a, the mist-like oil O adheres to the wall surface and is separated. And
The separated oil O accumulates in the lower part of one of the chambers 16a, 17a and returns to the swash plate chamber 8 through the return passages 54, 55. The refrigerant gas from which the oil O has been separated in one of the chambers 16a, 17a is passed through the through holes 57a, 57a.
8a into the other chambers 16b, 17b, one chamber 16a, 1
The oil O remaining without being separated in 7a is separated. Then, the separated oil O accumulates in the lower part of the other chambers 16b, 17b, and is returned to the swash plate chamber 8 through the return passages 54, 55.

In this embodiment, since the oil O is separated from the refrigerant gas twice, the efficiency of separating and recovering the oil O is higher than that of the above embodiment. Also, as in the previous embodiment, the suction chamber
Since the oil O is separated from the refrigerant gas in the insides 16 and 17, the oil is also supplied to the shaft seal 56 provided in the suction chamber 16 on the front side.

In this embodiment, the suction ports 20, 21 of the two cylinder bores 12 provided below the cylinder blocks 1, 2 are also provided.
Instead of a configuration that directly communicates with the suction chambers 16 and 17, thick portions are provided in the valve plates 3 and 4 as in the above-described embodiment, and the open ends of the thick portions are substantially in the center of the suction chambers 16 and 17. May be provided.

Seventh Embodiment Next, a seventh embodiment will be described with reference to FIGS. Also in this embodiment, the suction chambers 16, 17 are divided into two front and rear chambers 16a, 16b, 17a, 17b by partition walls 57, 58, and each chamber 16a, 16b, 1
Although the oil O is separated and recovered from the refrigerant gas in 7a and 17b, the refrigerant gas introduced from the swash plate chamber 8 into the suction chambers 16 and 17 is first supplied to the chambers 16b and 16b on the valve plate 3 and 4 side. 17b
Is different from the above embodiment. In this embodiment, instead of the cylindrical portions 57b and 58b connected to the suction passages 52 and 53, five cylindrical portions 57c and 58c connected to the respective suction ports 20 and 21 are formed on the partition walls 57 and 58. I have.

In this embodiment, the refrigerant gas in the swash plate chamber 8 is
After passing through the chambers 2 and 53, the oil is first introduced into the chambers 16b and 17b on the valve plates 3 and 4 side, and the mist-like oil O having a large specific gravity contained in the refrigerant gas is separated and falls to the lower part of the chambers 16b and 17b.
Further, when the flow of the refrigerant gas collides with the wall surfaces of the chambers 16b and 17b, the mist-like oil O adheres to the wall surfaces and is separated. The room
The refrigerant gas from which the oil O has been separated at 16b and 17b passes through the through holes 57a and 58a.
The refrigerant gas is introduced into the other chambers 16a and 17a through the
c, before being guided to 58c, the chambers 16b,
The oil O remaining without being separated in 17b is separated.
Then, the separated oil O accumulates in the lower part of the chambers 16a and 17a, and is returned to the swash plate chamber 8 through the return passages 54 and 55.

The present invention is not limited to the above embodiments. For example, instead of introducing the refrigerant gas returned to the compressor from the external cooling circuit into the swash plate chamber 8 from the gas inlet 28 formed in the cylinder block. The gas may be introduced through a gas inlet provided to penetrate the rear housing 6, or the discharge chambers 18, 19 may be formed at the center of the housing, and the suction chambers 16, 17 may be formed at the outer periphery of the housing. . Further, the present invention may be applied to a variable capacity swash plate type compressor.

[Effects of the Invention] As described above in detail, according to the present invention, a state in which a relatively large amount of mist-like oil is contained in the refrigerant gas before the refrigerant gas exiting the swash plate chamber is supplied to the compression chamber. The oil is separated and recovered from the refrigerant gas by the oil separation unit, and the separated and recovered oil is immediately inclined through the return passage provided so as to directly communicate between the lower part of the oil separation unit and the swash plate chamber. Since it is returned to the plate chamber, even when the compressor is operated in a state where the flow rate of the return refrigerant gas is small, it is possible to always secure an amount of oil necessary for lubrication of the thrust bearing, the shoe and the like. Also, unlike conventional compressors that separate and recover oil from refrigerant gas on the discharge side, the temperature of the separated and recovered oil does not become high enough to deteriorate the lubrication characteristics, so that the lubrication of each part is improved. Also, since the entire amount of the low-temperature refrigerant gas returned to the compressor from the external cooling circuit is first introduced into the swash plate chamber, the swash plate chamber and each sliding portion are cooled, and the lubrication characteristics of the oil are kept good. In addition to seizure, seizure of each sliding portion is prevented.

[Brief description of the drawings]

1 to 3 show a first embodiment of the present invention. FIG. 1 is a sectional view taken along line II of FIG. 2, and FIG. 2 is a line II-II of FIG. FIG. 3 is a sectional view taken along the line III-III of FIG. 1, FIG. 4 is a sectional view of a main part of the second embodiment, and FIGS. 5 and 6 show the third embodiment. FIG. 5 shows V- in FIG.
6 is a sectional view taken along the line VI-VI of FIG. 5, FIG. 7 is a sectional view of the fourth embodiment, FIG. 8 is a sectional view taken along the line VIII-VIII of FIG. FIG. 11 shows a fifth embodiment,
9 is a sectional view taken along line IX-IX of FIG. 10, and FIG.
FIG. 11 is a sectional view taken along the line XI-XI in FIG. 10, and FIG.
2 and 13 show the sixth embodiment, and FIG.
XII-XII sectional view of the figure, FIG. 13 is a sectional view taken along the line XIII-XIII of FIG. 12, FIGS. 14 to 16 show a seventh embodiment,
14 is a sectional view taken along line XIV-XIV of FIG. 15, and FIG. 15 is a sectional view of FIG.
FIG. 16 is a sectional view on the rear side at a position corresponding to the line XVI-XVI in FIG. 15, and FIG. 17 is a sectional view of the conventional device. Cylinder blocks 1 and 2, front housing 5, rear housing 6, swash plate chamber 8, drive shaft 10, swash plate 11, cylinder bore 12, piston 13, suction chambers 16 and 17, gas inlet 28 as suction port, oil separator 29 , Separation chamber 30, 43, return passage 3
3, 54, 55, suction passages 35, 36, 52, 53, compression chambers Pf, Pr, oil O.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Toshihiro Kawai 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (56) References JP-A-52-111630 (JP, A) JP-A Sho 57-210184 (JP, A) JP-A-49-25505 (JP, A) JP-A-57-56681 (JP, A) JP-A-56-55785 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04B 27/08

Claims (1)

(57) [Claims] A swash plate chamber and a cylinder bore located opposite to the front and rear sides of the swash plate chamber are formed in a cylinder block having front and rear housings joined at both front and rear ends. In a swash plate type compressor in which a piston performing a compression action on a rear side is reciprocally accommodated and the piston is reciprocally driven via a swash plate mounted on a drive shaft rotatably supported by the cylinder block, The swash plate chamber is provided with a suction port for returning refrigerant gas, an oil separation section is provided between the swash plate chamber and the compression chamber, and the oil separated by the oil separation section is returned to the swash plate chamber through the oil return passage. A swash plate compressor provided so as to directly communicate between a lower portion of a separation unit and a swash plate chamber.