KR20030052971A - Compressor and lubrication method thereof - Google Patents

Abstract

(Problem) To improve the lubrication effect of the drive mechanism for reciprocating the piston in the piston compressor.

(Solution means) A suction passage 41 for suctioning the suction refrigerant of the suction chamber 36 into the cylinder bores 16 and 17 to the drive shaft 9 to which the swash plate 14 for reciprocating the piston 18 is fixed. In the swash plate compressor 1, the oil supply hole 51 for flowing out lubricant oil in the refrigerant flowing through the suction passage 41 is formed in the crank chamber 8 in which the swash plate 14 is accommodated in the drive shaft 9 in the radial direction. Then, the lubricating oil is lubricated to the crank chamber 8 by using the centrifugal force by the rotation of the drive shaft 9. Further, the suction passage 41 is a stepped hole having a large diameter hole portion 41b and a small diameter hole portion 41c, and is formed along the inner wall surface of the suction passage 41 with a step 52 formed at the boundary between the two hole portions. It was set as the structure which prevents flowing lubricating oil, and changes a flow direction, and guides into the oil supply hole 51. FIG.

Description

Compressor and Lubrication Method of Compressor {COMPRESSOR AND LUBRICATION METHOD THEREOF}

The present invention relates, for example, to a piston type compressor suitable for vehicle air conditioning, and more particularly to a lubrication technique for inducing lubricating oil to a drive mechanism for reciprocating a piston.

As a compressor of this kind, there is, for example, Japanese Laid-Open Patent Publication No. Hei 6-101641. The compressor described in this publication is a double-headed piston type swash plate compressor, which forms a cylindrical hole with a spiral groove, one end of which is opened in the low pressure chamber (suction area) in the drive shaft, and the swash plate can be rotated inside the cylindrical hole. Lubrication holes for guiding lubricating oil are formed in the thrust bearings to be supported in a radial direction. The swash plate, which is a constituent member of the drive mechanism for reciprocating the piston by transferring the lubricating oil to the inside of the cylindrical hole along the spiral groove by using the rotation of the drive shaft, and lubricating the oil into the crank chamber through the thrust bearing at the lubricating hole. And lubricating the sliding surface of the shoe, the sliding surface of the shoe and the piston, and the sliding surface of the thrust bearing.

However, in the lubrication technique described in the above-mentioned publication, it is difficult to say that a sufficient lubricating effect is necessarily obtained, and there is room for improvement.

The present invention has been made in view of the above-described conventional problems, and an object thereof is to provide a lubrication technique that can further improve the lubrication effect of a drive mechanism for reciprocating a piston in a piston compressor.

BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal cross-sectional view which shows the double head piston swash plate compressor which concerns on embodiment.

2 is a partial cross-sectional view showing the main portion.

3 is a partial cross-sectional view showing another embodiment.

4 is a partial cross-sectional view showing another embodiment.

5 is a partial cross-sectional view showing another embodiment.

6 is a partial cross-sectional view showing another embodiment.

* Explanation of symbols on the main parts of the drawings

1: swash plate compressor 8: crankcase

9: drive shaft 14: swash plate

16, 17: cylinder bore 18: piston

20: drive mechanism 21, 22: thrust bearing

26: suction chamber (suction area) 41: suction passage (path)

41a: opening part (first communication part) 41b: large diameter hole part

41c: small diameter hole 51: oil supply hole (second communication part)

52: step (flow direction switching part) 53: pressure outlet hole (pressure outlet passage)

54: guide groove

Means to solve the problem

In order to achieve the said subject, the compressor which concerns on this invention was provided with the structure as described in each claim of the claim. The invention according to the claims further includes a drive shaft, a piston for reciprocating the cylinder bore to compress the refrigerant, a drive mechanism for transmitting the rotational movement of the drive shaft to the piston in a reciprocating motion, and a crank chamber accommodating the drive mechanism. In a compressor, this technique is capable of lubricating a drive mechanism in the crank chamber by lubricating oil in the crank chamber.

In the invention according to claim 1, a passage through which the refrigerant passes is formed in the drive shaft, and the passage prevents the first communication portion through the suction region, the second communication portion through the crank chamber, and the lubricant oil mixed with the refrigerant and flowed in. It is set as the structure which has a flow direction switching part which changes a direction and guides to a 2nd communication part. Therefore, during operation of the compressor, the refrigerant and the lubricating oil mixed therein flow into the passage via the first communication portion in the suction region. Most of the lubricating oil adheres to the inner wall surface of the passage due to its properties, and is blocked by the flow direction switching unit to change the flow direction, and then flows out to the crank chamber via the second communication unit. In this case, since the flow direction switching part is formed in the invention of Claim 1, the lubricating oil which flowed in along the inner wall surface of a channel | path is blocked by the flow direction switching part, and is guide | induced to a 2nd communication part. Therefore, lubricating oil collects efficiently in a 2nd communication part, and actively flows out to a crank chamber by the centrifugal force by rotation of a drive shaft. As a result, the crank chamber is lubricated with the amount of lubricant required for lubrication of the drive mechanism, thereby improving the lubrication performance.

In the case of a swash plate compressor, for example, the lubrication portion of the drive mechanism accommodated in the crank chamber includes a sliding surface of the thrust bearing, a sliding surface of the swash plate and the shoe, a sliding surface of the shoe and the piston, etc. to support the swash plate to rotate. This is the case.

Further, according to the invention of claim 1, by forming the second communication portion connecting the passage and the crank chamber to the drive shaft, the effect of separating the lubricant oil using the centrifugal force of the drive shaft and the storage effect of the lubricant oil by the crank chamber can be obtained.

In the invention according to claim 2, the passage is a suction passage formed for inducing refrigerant to the cylinder bore. Thereby, a more aggressive lubricating oil flow can be obtained, and the lubricating oil supply effect to a crankcase can be improved further.

In the invention according to claim 3, the configuration has a pressure withdrawing passage for guiding the refrigerant in the crank chamber to a region having a lower pressure than the crank chamber. As a result, the pressure in the crank chamber can be lowered, and as a result, the lubricating oil can be discharged more actively from the second communication portion to the crank chamber.

In this case, as described in claim 4, the pressure withdrawing passage is preferably a pressure withdrawing hole communicating with the crank chamber and the passage. According to this configuration, the pressure withdrawing passage can be formed simply by forming a hole in the drive shaft.

Moreover, in invention of Claim 5, the drive mechanism has the swash plate which rotates with a drive shaft, and it set it as the structure which the outlet of a 2nd communication part opens toward the thrust bearing which supports this swash plate to rotate. According to such a configuration, the thrust bearing can be lubricated intensively.

In invention of Claim 6, the flow direction change part is comprised by the wall surface of the direction which intersects the inner wall surface of a channel | path. In this case, the wall surface can be configured, for example, by making the passage a stepped hole or by forming an annular recess in the inner wall surface of the passage, and setting the inlet of the second communication portion toward the wall surface so that the lubricant can be efficiently You can guide.

In the invention according to claim 7, a guide groove for guiding lubricating oil is formed along the inner wall surface of the passage, and the inlet of the second communication portion is opened at the edge end of the guide groove. According to this, since the lubricating oil introduced into the guide groove can be efficiently guided to the second communication portion at the edge of the guide groove and flows out into the crank chamber, the oil supply effect to the crank chamber can be further improved.

In the invention according to claim 8, the flow direction switching section and the second communication section have one set, and a plurality of sets are provided in the flow direction of the passage. According to this, since the oil supply to a crankcase can be performed in multiple stages, the oil supply effect is raised.

In the invention according to claim 9, the outlet of the second communication portion is configured to open toward a swash plate at a position corresponding to the top dead center of the piston and a shoe interposed between the swash plate and the piston. As a result, lubricating oil can be reliably supplied to the point where the load applied to the swash plate and the shoe is large, and the durability of the compressor can be further improved.

According to the invention as set forth in claim 10, it is possible to provide a lubrication method of a compressor effective for efficiently lubricating an amount of lubricating oil necessary for lubrication of a drive mechanism in a crank chamber, and for improving the lubrication effect of the drive mechanism.

Embodiment of the invention

EMBODIMENT OF THE INVENTION Next, embodiment of this invention is described based on drawing. 1 is a longitudinal sectional view of a compressor, and FIG. 2 is a partial cross-sectional view showing the main portion. This embodiment is applied to the double head piston swash plate compressor. As shown in FIG. 1, the main body of the swash plate compressor 1 includes a cylinder block 2 in the center portion, a front housing 3 lubricated through a valve plate 4 at the front end of the cylinder block 2, and a cylinder block ( It is comprised by the rear housing 5 lubricated through the valve plate 6 at the rear end of 2). In addition, the cylinder block 2 is divided into the front cylinder block 2a and the rear cylinder block 2b. The constituent members of the main body are fastened to each other by a through bolt (7).

In the crank chamber (swash plate chamber 8) formed inside the cylinder block 2, the drive shaft 9 which rotationally drives the engine of a vehicle as a drive source, for example, is inserted in the front side (left side of FIG. 1), and this drive shaft 9 ) Is rotatably supported by a pair of journal bearings 11 and 12 before and after the crank chamber 8. The swash plate 14 is accommodated in the crank chamber 8, and the swash plate 14 is fixed to the drive shaft 9 by means suitable for the drive plate 9.

On the other hand, in the front cylinder block 2a, a plurality of, for example, five cylinder bores 16 are formed parallel to each other at equal positions around the center (center of rotation of the drive shaft 9), and correspondingly to the rear cylinder In the block 2b, a plurality of cylinder bores 17 are formed in the same manner. In the cylinder bores 16 and 17, both head pistons 18 are fitted so as to slide in the axial direction. The piston 18 has a groove part in the substantially center part of an axial direction, and is arrange | positioned so that the circumferential edge part of the swash plate 14 may be caught by this groove part. On both sides of the groove portion of the piston 18, spherical recesses 18a are formed, and the piston 18 is swash plate 14 via a substantially hemispherical shoe 19 engaged with the recesses 18a. Is hanging on. The shoe 19 is interposed between the piston 18 and the swash plate 14 and slides with respect to the two members, respectively.

When the drive shaft 9 is rotated, this rotational motion is converted into a linear reciprocating motion of the piston 18 via the swash plate 14 and the shoe 19. The swash plate 14 and the shoe 19 correspond to the drive mechanism 20 according to the present invention. The axial load as a reaction force generated in the drive shaft 9 by the linear movement of the piston 18 is supported by a pair of thrust bearings 21 and 22 provided on both sides of the swash plate 14.

The annular discharge chamber 24 is formed in the outer peripheral part in the front housing 3, and the annular discharge chamber 25 is formed in the outer peripheral part in the rear housing 5, too. Moreover, the suction chamber 26 partitioned from the discharge chamber 25 by the partition is formed in the substantially center part of the rear housing 5. The suction chamber 26 is provided with an inlet 27, and suction suction from an external refrigeration circuit is introduced by a suction pipe (not shown) connected thereto.

The front side valve plate 4 is provided with a discharge port 31 communicating with the compression chamber that is enlarged / reduced by the reciprocating movement of the piston 18 and the front discharge chamber 24 in the cylinder bore 16, and the discharge port is provided. On the downstream side of the 31 (back side of the compression chamber), a discharge valve 33 made of a thin plate spring whose opening valve angle is restricted by the valve press 32 is provided. Similarly, the rear valve plate 6 is formed with a discharge port 34 communicating with the compression chamber that is enlarged / reduced by the reciprocating movement of the piston 18 and the rear discharge chamber 25 in the cylinder bore 17. On the downstream side of this discharge port 34, a discharge valve 36 made of a thin plate spring whose opening valve angle is regulated by the valve presser 35 is provided. In addition, the front and rear discharge chambers 24 and 25 communicate with each other by a pipe not shown, so that the high-pressure refrigerants discharged from the two discharge chambers 24 and 25 join and flow out to an external refrigeration circuit. It is.

The journal bearings 11 and 12 for rotationally supporting the drive shaft 9 are mainly formed in the through holes 38 and 39 formed so as to have the same axis at the center of each of the front cylinder block 2a and the rear cylinder block 2b. With the slide bearing pressed in, the journal parts 9a and 9b which are a part of the drive shaft 9 itself are supported so that rotation is possible. A part of the drive shaft 9 is formed in the hollow of the circular cross section, thereby constituting the suction passage 41 of the suction refrigerant. The suction passage 41 has one end (right end in FIG. 1) opened and the opening 41a communicates with the suction chamber 26 (corresponding to the area described in the present invention).

A fan-shaped suction opening 43 communicating with the suction passage 41 in the front side journal portion 9a of the drive shaft 9 and opened at a predetermined angle, for example, about 130 ° in the circumferential direction with respect to the axis of the drive shaft 9 in the radial direction. Is formed. Similarly, the rear side journal portion 9b is also connected to the suction passage 41 so that a fan-shaped suction opening 44 is opened radially in a circumferential direction with respect to the axis of the drive shaft 9 at a predetermined angle, for example, about 130 °. The front suction opening 43 and the rear suction opening 44 have a 180 ° phase difference in the circumferential direction.

The front side journal bearing 11 and the cylinder block 2a communicate with each other when the drive shaft 9 is in a predetermined rotational position (angle) with respect to the front side suction opening 43, thereby allowing the refrigerant in the suction passage 41 to reach the front side journal bearing 11 and the cylinder block 2a. The suction port 45 of the radial direction which inhales into each of the front side several cylinder bore 16 at the suction opening 43 is formed. In addition, the rear journal bearing 12 and the cylinder block 2b are also connected to the rear suction opening 44 in the same manner as the drive shafts 9 are located at predetermined rotation positions, respectively. A radial suction port 46 is formed in which the refrigerant is sucked into each of the plurality of rear cylinder bores 17 at the suction opening 44.

When the drive shaft 9 is rotated, the piston 18 reciprocates in the cylinder bore 16, 17 via the swash plate 14 and the shoe 19, but at the same time the front and rear journals of the drive shaft 9 The suction openings 43 and 44 of the sections 9a and 9b are rotated, and the front suction opening 43 is sequentially in the cylinder bore 16 with respect to the suction port 45 corresponding to that which entered the suction stroke at this time. To communicate with. Similarly, among the rear suction opening 44 do cylinder bore 17, it communicates sequentially with respect to the suction port 46 corresponding to what entered into the suction stroke at this time. In this communication relationship, the opening angles (areas) of the suction openings 43 and 44 are set for any of the cylinder bores 16 and 17 so as to continue while they are in the suction stroke.

When the cylinder bores 16 and 17 are shifted from the suction stroke to the compression stroke, the corresponding suction ports 45 and 46 are formed by the outer circumferential surfaces of the journal portions 9a and 9b of the drive shaft 9. It is blocked. Suction ports 43,44 formed in the journal portions 9a, 9b of these drive shafts 9 and suction ports communicating / closing (opening / closing) with respect to the suction openings 43,44 in accordance with the rotation of the drive shafts 9 ( 45, 46) consists of a rotary valve.

Therefore, when the piston 18 reciprocates in the cylinder bores 16 and 17, the refrigerant in the suction chamber 26 is sucked into the cylinder bores 16 and 17 through the rotary valve in the suction passage 41, While being compressed, they are discharged to the discharge chambers 24 and 25 through the discharge valves 33 and 36. The suction stroke is displayed on the left side (front side) of FIG. 1, and the discharge stroke is displayed on the right side (rear side). In Fig. 1, the flow direction of the refrigerant is indicated by an arrow.

Next, the technique of lubricating the drive mechanism 20 in the crank chamber 8 which is the characteristic point of this embodiment is demonstrated. As shown in FIG.1 and FIG.2, the drive shaft 9 is provided with the oil supply hole 51 which communicates the suction path 41 of refrigerant | coolant with the crank chamber 8 in radial direction. One or more oil supply holes 51 are formed in the circumferential direction, one end (inlet) is opened in the suction passage 41, and the other end (outlet) is opened in the rear side thrust bearing 22. This oil supply hole 51 flows the lubricating oil which flows in with the refrigerant in the suction passage 41 toward the thrust bearing 22 using the centrifugal force at the time of coaxial movement of the drive shaft 9, and again of this thrust bearing 22 It flows out into the crank chamber 8 at a clearance gap. In this case, in this embodiment, as shown in FIG. 1, the oil supply hole 51 faces the swash plate 14 and the shoe 19 in the position corresponding to the top dead center vicinity of the piston 18 via the thrust bearing 22. As shown in FIG. It is open. Therefore, lubricating oil can be reliably supplied to the point where the load applied to the swash plate 14 and the shoe 19 from the piston 18 is large, and the durability of a compressor can be improved further. In the figure, the flow direction of the lubricating oil is indicated by arrows.

Lubricating oil in the refrigerant flowing into the suction passage 41 flows along the inner wall surface of the suction passage 14 due to its properties. In order to guide this lubricating oil efficiently to the inlet of the oil supply hole 51, in this embodiment, the suction path 41 communicated with the suction chamber 26 has a larger inner diameter than the inner diameter of the front side (inner side). The formed stepped hole is used. Therefore, at the boundary between the large diameter hole portion 41b and the small diameter hole portion 41c, an annular step 52 constituting a wall surface in a direction intersecting the inner wall surface of the suction passage 41 is formed. Is set at a portion corresponding to the inlet of the oil supply hole 51. In other words, the wall surface of the step 52 and the wall surface of the oil supply hole 51 are set to be continuous at the same level.

The step 52 prevents the flow of the lubricating oil flowing along the inner wall surface of the large diameter hole portion 41b when the refrigerant flows in the suction passage 41, and also changes the flow direction thereof so that the inlet of the oil supply hole 51 is changed. Has the ability to induce. That is, the step 52 corresponds to the flow direction switching section of the lubricating oil in the present invention. In addition, the suction passage 41 corresponds to the passage in the present invention, and the opening 41a of the suction passage 41 in communication with the suction chamber 26 corresponds to the first communication portion in the present invention, and the oil supply hole (51) This corresponds to the second communication path in the present invention.

In the compression stroke of the cylinder bores 16 and 17, some refrigerant in the compression chamber leaks into the crank chamber 8 via the sliding surface of the piston 18 and the cylinder bores 16 and 17, and the pressure in the crank chamber 8 is reduced. This is likely to be high. In order to lower this pressure, one or more pressure taking-out holes 53 are formed in the drive shaft 9 in the radial direction. The pressure outlet hole 53 is formed in a portion corresponding to the front side thrust bearing 21, one end of which is opened in the suction passage 41, and the other end passes through the gap of the thrust bearing 21 so as to form the crank chamber 8 Is open to. The pressure drawing hole 53 corresponds to the pressure drawing passage as used in the present invention.

The swash plate compressor 1 which concerns on this embodiment is comprised as mentioned above. Therefore, when the drive shaft 9 is driven to rotate, the double head piston 18 moves into the cylinder bore 16, 17 through the shoe 19 by the swinging motion of the swash plate 14 which is integrally formed with the drive shaft 9 and rotates. The compression chamber in the cylinder bores 16 and 17 is expanded / reduced by reciprocating movement. On the other hand, in accordance with the rotation of the drive shaft 9, the rotary valve composed of the suction openings 43 and 44 and the suction ports 45 and 46 is opened and closed.

As a result, the suction chamber 41 is sequentially communicated with the suction passage 41 from the cylinder bore 16 and 17 by entering the suction stroke, so that the suction chamber 26 is connected to the compression chamber of the cylinder bore 16 and 17 by an external refrigeration circuit. Through this, the refrigerant introduced into the suction passage 41 is sucked in. Then, when the piston 18 reaches the bottom dead center, the suction stroke is ended, and then the piston 18 is inverted and shifted to the compression stroke, but the suction passages sequentially from the cylinder bores 16 and 17 shifted to the compression stroke. Communication to (41) is blocked. The refrigerant compressed in the cylinder bore (16,17) of the compression stroke is discharged to the discharge chamber (24,25) while pushing the discharge valve (33,36) in the discharge port (31,34) to the external refrigeration circuit It is sent out.

During the operation, the lubricating oil mixed into the refrigerant and introduced into the suction passage 41 flows out toward the rear thrust bearing 22 through the oil supply hole 51 by centrifugal force generated by the rotation of the drive shaft 9. The oil is fed into the crank chamber 8 through the gap between the thrust bearings 22.

In this case, most of the lubricating oil flowing into the suction passage 41 adheres to the inner wall surface of the suction passage 41 and flows due to its properties. In this embodiment, since the large diameter hole part 41b is formed in the upstream side of the suction path 41, the lubricating oil which flows along the inner wall surface of the large diameter hole part 41b is the level | step difference which is a boundary surface with the small diameter hole part 41c ( 52, the flow is blocked and the flow direction is changed to lead to the inlet of the oil supply hole 51. Thereby, oil supply to the crank chamber 8 can be performed efficiently.

Moreover, in this embodiment, the pressure take-out hole 53 which connects the crank chamber 8 to the suction path 41 in the downstream of the oil supply hole 51 is formed. Therefore, even if a part of the refrigerant compressed in the cylinder bores 16 and 17 leaks into the crank chamber 8 from the sliding surfaces of the cylinder bores 16 and 17 and the pressure in the crank chamber 8 becomes high. The refrigerant in the crank chamber 8 flows out through the pressure outlet hole 53 into the suction passage 41, which is a space having a lower pressure than the crank chamber 8. As a result, the pressure in the crank chamber 8 decreases, so that the lubricating oil easily flows from the suction passage 41 to the crank chamber 8 through the oil supply hole 51.

In the present embodiment, a suction passage 41 for sucking refrigerant into the cylinder bores 16 and 17 is used as a passage for lubricating oil to be led into the crank chamber 8. That is, since the suction passage 41 through which the refrigerant actively flows is used as the oil supply passage, a large amount of lubricant can be easily secured, and as a result, the oil supply effect of the lubricant to the crank chamber 8 can be improved.

Thus, according to this embodiment, since lubricating oil can be supplied to the crank chamber 8 efficiently and actively, it becomes possible to pass via sufficient amount of lubricating oil required for lubrication. Thereby, the swash plate 14 and the shoe 19 which are the structural members of the drive mechanism 20 accommodated in the crank chamber 8, the sliding surface of the shoe 19, the piston 18, etc. can be lubricated and cooled. Can be. In addition, the rear thrust bearing 22 can be lubricated by lubricating oil directly from the lubrication hole 51, and lubricating oil can be lubricated effectively through the refrigerant flow passing through the pressure outlet hole 53 on the other front side. Can be.

Further, according to the present embodiment, since the lubricating oil in the refrigerant sucked into the suction passage 41 is separated by centrifugal force of the drive shaft 9 and lubricated through the radial oil supply holes 51, at least the oil supply holes 51 Lubricant in the refrigerant sucked into the front cylinder bore 16, which is further downstream, can be reduced. As a result, the lubrication contained in the refrigerant sent to the external refrigeration circuit can be reduced, and the heat exchange performance of the heat exchanger provided in the refrigeration circuit is improved. In addition, the lubricating oil lubricated into the crank chamber 8 is stored at the bottom of the crank chamber 8.

Next, another embodiment of the present invention will be described. In another embodiment shown in FIG. 3, a guide groove 54 of lubricating oil is formed on the inner wall surface of the suction passage 41 to extend in the axial direction to a stepped hole. At least one guide groove 54 is set in the circumferential direction, and oil supply holes 51 that are radially opened in a form communicating with the guide groove 54 are formed. Accordingly, the side surface 54a of the edge end of the guide groove 54 constitutes the flow direction switching section in the present invention. When such a guide groove 54 is formed, the lubricating oil adhering to the guide groove 54 can be guided intensively to the oil supply hole 51 so that the oil can be supplied to the crank chamber 8 more efficiently. .

Moreover, in the case of the guide groove 54, the position of the oil supply hole 51 does not necessarily need to be continuous in the wall surface of the same level with respect to the wall surface 54a of the guide groove 54, As shown in the figure Lubricating oil can be guided smoothly to the oil supply hole 51 even in front of 54a.

Next, in another embodiment shown in FIG. 4, the suction passage 41 is formed into a two-step step hole formed of a large diameter hole portion 41d, a medium diameter hole portion 41e, and a small diameter hole portion 41f in order from the upstream side. do. Then, the step 56 of the large diameter hole 41d and the middle diameter hole 41e is set to a portion corresponding to the rear side thrust bearing 22, and the rear side oil supply hole ( 57, and the step 58 of the middle diameter hole 41e and the small diameter hole 41f is set at a portion corresponding to the front side thrust bearing 21, and correspondingly to the step 58. The oil supply hole 59 is formed.

That is, in another embodiment shown in FIG. 4, the lubricating oil which flows along the inner wall surface of the oil supply hole 57 and 59 and the suction path 41 for guiding the lubricating oil in the suction path 41 to the crank chamber 8 is flow direction. By setting two sets of steps 56, 58 leading to the oil supply holes 57, 59, the oil supply effect to the crank chamber 8 can be further improved.

Moreover, in another embodiment shown in FIG. 4, the oil supply hole 57, 59 opens toward the swash plate 14 and the shoe 19 which are near the top dead center of the piston 18 via thrust bearings 21 and 22, respectively. It is. Therefore, the lubricating oil can be reliably supplied to the point where the load applied to the swash plate 14 and the shoe 19 from the piston 18 is large, and the durability of the compressor can be further improved.

In addition, this invention is not limited to embodiment mentioned above, It can change suitably within the range which does not deviate from the summary.

For example, the embodiment shown in Figs. 1 to 4 shows a case where the oil supply holes 51, 57 and 59 extend in the radial direction at substantially right angles with respect to the rotation axis of the drive shaft 9, as shown in Fig. 5. Similarly, it may be inclined with respect to the rotation axis. Moreover, as shown in FIG. 6, it can also incline with respect to the radial line (normal line) passing through the drive shaft 9 center. In other words, it is preferable that the shapes of the oil supply holes 51, 57, 59 are formed so that the resistance of the flow is very small.

In addition, in the embodiment shown in FIGS. 1-4, the suction passage 41 formed in the drive shaft 9 for sucking refrigerant into the cylinder bores 16, 17 was used as the oil supply passage, but the discharge passage in the drive shaft 9 was used. Alternatively, a refrigerant passage for oil supply may be formed.

The oil supply hole 51 can be changed to the structure which opens to the thrust bearing 22, and can also be changed to the structure which penetrates the crank chamber 8 through the swash plate 14. As shown in FIG. The outlet of the pressure withdrawal hole 53 for drawing out the pressure of the crank chamber 8 is not limited to the suction passage 41 but may be a space having a lower pressure than the crank chamber 8.

In addition, although the above-mentioned embodiment demonstrated the double head piston swash plate compressor, it can also apply to a double head piston swash plate compressor. The drive mechanism 20 for reciprocating the piston 18 is not limited to the swash plate type.

As described above, the present invention can provide a lubrication technique that can further improve the lubrication effect of a drive mechanism for reciprocating the piston in a piston compressor.

Claims (10)

A compressor having a drive shaft, a piston for reciprocating a cylinder bore to compress refrigerant, a drive mechanism for transmitting a rotational movement of the drive shaft to the piston in a reciprocating motion, and a crank chamber accommodating the drive mechanism, A passage through which refrigerant passes is formed in the drive shaft, and the passage prevents the first communication portion through the suction region, the second communication portion through the crank chamber, and the lubricating oil introduced into the refrigerant to change the flow direction. And a flow direction switching unit leading to the second communication unit. The compressor as claimed in claim 1, wherein the passage is a suction passage formed to induce suction refrigerant in the cylinder bore. The compressor according to claim 1 or 2, further comprising a pressure withdrawing passage for guiding the refrigerant in the crank chamber to a space having a lower pressure than the crank chamber. 4. The compressor as set forth in claim 3, wherein said pressure drawing passage is a pressure drawing hole formed in said drive shaft for communicating said crank chamber with said passage. The said drive mechanism has a swash plate which rotates with the said drive shaft, The outlet of the said 2nd communicating part is opened toward the thrust bearing which supports this swash plate so that it may rotate. Compressor. 3. The inlet according to claim 1 or 2, wherein the flow direction switching portion is constituted by a wall surface in a direction crossing the inner wall surface of the passage, and an inlet of the second communication portion is opened in the inner wall surface of the portion crossing the wall surface. Compressor characterized in that there is. The compressor according to claim 6, wherein a guide groove for guiding lubricating oil is formed along the inner wall surface of the passage, and an inlet of the second communication portion is opened at an edge of the guide groove. The compressor according to claim 1 or 2, wherein the flow direction switching section and the second communication section are provided as a set in a plurality, and a plurality of sets are provided in the flow direction of the passage. The compressor according to claim 1 or 2, wherein the outlet of the second communication portion is opened toward a swash plate at a position corresponding to near the top dead center of the piston and a shoe interposed between the swash plate and the piston. A lubrication method of a compressor comprising a drive shaft, a piston for reciprocating a cylinder bore to compress refrigerant, a drive mechanism for transmitting a rotational movement of the drive shaft to the piston in a reciprocating motion, and a crank chamber accommodating the drive mechanism, A passage through which refrigerant passes is formed in the drive shaft, and the passage prevents the first communication portion through the suction region, the second communication portion through the crank chamber, and the lubricating oil introduced into the refrigerant to change the flow direction. And a flow direction switching unit leading to the second communication unit, mixed with and flowing into the refrigerant in the first communication unit, and redirected by the flow direction switching unit to the lubricating oil by the centrifugal force by the rotation of the drive shaft. 2. A lubrication method of a compressor, characterized by lubricating a sliding portion of the drive mechanism by flowing out of a communication section into the crank chamber.