JP2938812B2 - Swash plate compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swash plate type compressor used in an automotive air conditioning system.

[0002]

2. Description of the Related Art A swash plate compressor is one of compressors that are incorporated in an air conditioning system for a vehicle and perform a compression work by receiving the rotational power of a vehicle-mounted engine. In a swash plate compressor, the rotational motion of a shaft rotated by receiving the rotational power of an engine is converted into reciprocating motions of a plurality of pistons.

In order to convert the motion, a circular swash plate obliquely crossing the shaft is attached to the shaft, and each piston is provided with a recess for receiving a part of the swash plate. The swash plate and each piston are in contact with each other via a bearing member arranged in the depression of each piston, and a thrust bearing for reducing the rotational resistance of the swash plate is arranged around the shaft. ing.

[0004] The swash plate rotates together with the shaft, and during rotation, the position of each portion in the circumferential direction of the swash plate in the axial direction of the shaft changes. Therefore, each piston in contact with the swash plate is forcibly displaced in the axial direction and reciprocates. As a result, in the automotive air conditioning system, the refrigerant supplied from the outside of the housing of the swash plate compressor to the inside is compressed, and the compressed refrigerant is discharged to the outside of the housing.

[0005] In the swash plate type compressor, when the operation is started, a part of the lubricating oil accumulated at the bottom of the housing travels along the swash plate, and the evaporation component of the lubricating oil is reduced. Along with the refrigerant, each of the pistons enters the depression of each piston, and is provided between the swash plate and the bearing member and for lubrication of the thrust bearing. But,
Actually, the supply of the lubricating oil may not be sufficient, so that a seizure occurs between the swash plate and the bearing member or the race of the thrust bearing in a short time after starting, The rotation of the shaft may stop.

However, after the rotation of the shaft is stopped due to seizure, the shaft continues to receive the rotational power of the vehicle-mounted engine via a power transmission member attached to the free end of the shaft. As a result, the free end of the shaft is twisted, and the free end that has left the swash plate compressor hits the equipment around the swash plate compressor together with the rotary power transmission member, and may damage them. Was.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to hold a swash plate compressor so that when a free end of a shaft of the swash plate compressor is twisted, it is not separated from the swash plate compressor.

[0008]

SUMMARY OF THE INVENTION A swash plate compressor has a housing having a main body and a tubular portion, and a cylinder block having a plurality of cylinders housed in the main body of the housing. A shaft is rotatably mounted on the cylinder block and has a free end protruding from the cylinder block. A swash plate is fixed to the shaft, and the swash plate is rotatable with the shaft. A piston that can reciprocate in the axial direction of each cylinder is disposed in each cylinder of the cylinder block. Each piston has a recess for receiving a portion of the swash plate. A ring member is disposed coaxially within the tubular portion of the housing. The free end of the shaft has a tip portion having a smaller diameter than the inner diameter of the ring member and a base portion having a larger diameter, and the tip portion penetrates the ring member.

[0009]

According to the present invention, the rotation of the shaft is stopped due to the occurrence of seizure in the swash plate type compressor, and when the free end of the shaft is twisted off, the housing is prevented. A ring member within the tubular portion of the shaft prevents passage through the base of the free end of the shaft that is larger than its inner diameter. As a result, the free end of the shaft separated by twisting is prevented from coming out of the tubular portion, and is retained in the tubular portion. Thus, it is possible to prevent equipment in the engine room where the swash plate compressor is arranged from being damaged.

The ring member can be fixed to the tubular portion by providing a circumferential groove on the inner wall of the tubular portion of the housing and arranging a snap ring surrounding the distal end of the shaft in the circumferential groove.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, a swash plate compressor is indicated generally by the numeral 10.

The swash plate type compressor 10 includes a housing 12,
Cylinder block 14 housed in housing 12
And a shaft 15 rotatably supported by the cylinder block 14, a swash plate 16 fixed to the shaft 15, and a plurality (5 in the illustrated example) provided on the cylinder block 14.
) And a plurality of pistons 18 arranged in the respective cylinders 17.

The housing 12 has a generally cylindrical main body 19.
And a reduced-diameter tube portion (tubular portion) 20 extending from one end of the main body 19 and a cap 21 fixed to and covering the open end (the other end) of the main body 19.

The body 19 of the housing 12 has two depressions 22, 24 inside. Both recesses 22, 24
Are provided at the top and the bottom of the main body 19, respectively, and are located substantially in the middle between both ends in the axial direction of the main body 19. The recess 22 at the top defines a space for receiving a refrigerant introduced into the housing via a port (not shown) provided in the main body 19. Further, the recess 24 at the bottom forms an oil pan (oil pan). These depressions 22, 24 are
Valve plate 3 which defines a sealed space in the main body 19
The lubricating oil is sealed in the closed space between the lubricating oils 4 and 36. The level of the lubricating oil is equal to the swash plate type compressor 10
Is normally at a height position directly below the shaft 15 when the operation is stopped.

The cylinder block 14 housed in the main body 19 of the housing 12 is in contact with the inner wall surface 25 extending in the circumferential direction of the main body 19, and has both side portions 28 and a top portion 30 (FIG. 2) which define a part of a circular surface. Having. Each side 28 and top 30 cooperate with the body 19 to mount the housing 12 on top of the body.
Defines a passage 32 for the refrigerant extending in the axial direction of the refrigerant.

The plurality of cylinders 17 provided on the cylinder block 14 are spaced from each other around the axis of the cylinder block 14. Each cylinder 17
Extends in the direction of the axis and is open at both end surfaces of the cylinder block 14. Both end surfaces of the cylinder block 14 are in contact with one end of the main body 19 and the cap 21 via a pair of valve plates 34 and 36, respectively.

One of the valve plates 34 is provided with two holes 42 and 44 which communicate with the respective cylinders 17 and two concentric annular spaces 38 and 40 provided in the main body 19 of the housing. . Further, the other valve plate 36 is provided with two holes 50 and 52 that communicate with the respective cylinders 27 and the two annular spaces 46 and 48 provided in the cap 21. In practice, a check valve (not shown) is located in each of the holes 42, 44, 50, 52, and the refrigerant moves between the cylinder and the annular space via the check valve.

By the reciprocating motion of each piston 18 in each cylinder 17 in the axial direction, the refrigerant discharged from the evaporator forming a part of the automotive air conditioning system is transferred to the housing 1.
2 into the recess or space 22 at the top, from the space 22 to the inner annular spaces 38, 46 via the respective passages 32,
Further, each valve plate 3 is removed from each annular space 38, 46.
It is sucked into each cylinder 17 through the holes 42 and 50 of 4,36.

The refrigerant compressed by the reciprocating motion of each piston 18 is supplied to each of the holes 44,
It is extruded through 52 into the outer annular spaces 40, 48.
The two annular spaces 40 and 48 communicate with each other via a pipe 54 that is passed through a hole penetrating the cylinder block 14 in the axial direction thereof.
It is discharged to the outside of the swash plate type compressor 10 through a port 56 connected to one space 48. The discharged compressed refrigerant is sent to a condenser (not shown) forming a part of the air conditioning system.

The shaft 15 is connected to the reduced diameter tube portion 2 of the housing.
0, and passes through the cylinder block 14 along its axis. More specifically, the shaft 15 passes through a pair of bearing journals 59 (shown only in FIG. 1) spaced apart from each other in a hole provided in the cylinder block 14 and passing through the center of the cylinder block. doing. The shaft 15 has a pair of radial bearings 60.
Is rotatably supported by the cylinder block 14. Each radial bearing 60 is supported by each bearing journal 59.

The shaft 15 is rotated by receiving the rotational power of a vehicle-mounted engine (not shown). The rotational power of the engine is transmitted to the shaft 15 via the clutch 62. The clutch 62 is connected to the reduced-diameter tube portion 2 of the housing 12.
The rotor 66 is rotatably supported around a radial bearing 64 via a radial bearing 64, and is fixed to a distal end portion 67a of a portion 67 projecting from the free end of the shaft 15, that is, the cylinder block 14, and extending within the tubular portion 20 of the housing. A friction plate (rotational power transmission member) 68 opposed to the rotor 66 at a small interval is included.

The rotor 66 of the clutch 62 receives the rotational power of the engine via a belt (not shown) and rotates. The rotor 66 has a built-in electromagnet 67 extending annularly around its rotation axis. When the electromagnet 67 is energized, the magnetic force generated by this magnet causes the friction plate 68 to be elastically deformed and come into contact with the rotor 66. As a result, the friction plate 68 and the shaft 15 in a fixed relation to the friction plate 68 make a rotational movement.

The rotational movement of the shaft 15 is converted into a reciprocating movement of each piston 18 via the swash plate 16.

The swash plate 16 is composed of a boss 70 passed through the shaft 15 and fixed thereto, and a disk 72 extending from the boss 70. The boss 70 is disposed between the bearing journals 59, and a thrust bearing 74 is disposed between the boss 70 and each bearing journal 59.

The disk portion 72 of the swash plate is inclined with respect to the shaft 15. That is, the disk portion 72 forms an intersection angle other than 90 degrees with the shaft 15. For this reason,
When the swash plate 16 rotates together with the shaft 15, the disk portion 7
The position of an arbitrary part in the circumferential direction of the shaft 2
With respect to the axial direction of.

Each piston 18 disposed in each cylinder 17 of the cylinder block has a recess 76 for receiving the disk 72 of the swash plate 16. A disc-shaped shoe 78 in contact with each surface of the disc portion 72 and a shoe 78
And a ball 80 rotatably held on a wall defining the depression 76. The disc portion 72 is connected to each piston 18 via these shoes 78 and balls 80.
Is in contact with

From this, when the swash plate 16 rotates,
Each piston 18 in contact with the disk portion 72 is forcibly displaced in the axial direction of each piston by the disk portion, thereby reciprocating.

In the illustrated example, two pistons (first pistons) 18 and a cylinder (first cylinder) 17 for receiving the two pistons are located below the liquid level of the lubricating oil. For this reason, a part of the recesses 76 of these two first pistons 18 is filled with the lubricating oil, and therefore each shoe 7 in these recesses 76
No replenishment of lubricating oil to the ball 8 and the ball 80 is required. However, the number of pistons 18 located below the level of the lubricating oil differs depending on the total number, diameter, etc. of the pistons 18.

On the other hand, as for the shoes 78 and the balls 80 in the recesses 76 of the remaining three pistons 18 at the upper positions, a part of the swash plate 16, that is, a tip part of the disk part 72 becomes a part of the lubricating oil. Swash plate type compressor 1
The lubrication is performed when the swash plate 16 is rotated by the start of zero. Further, the evaporation component of the lubricating oil generated after the start of the swash plate type compressor 10 enters the depression 76 of each piston 18 together with the refrigerant flowing in the housing 12, and the thrust bearing 74, the shoe 78 and the disc portion 72 The contact part is lubricated. However, in a short time after starting, the supply of the lubricating oil to these portions is not sufficient, and therefore, seizure occurs at a contact portion between the shoe 78 and the disc portion 72 or a contact portion with the race portion of the thrust bearing. And rotation of the shaft 15 may stop.

Even if the rotation of the shaft 15 stops due to the occurrence of seizure, the shaft 15 continues to receive the rotational power via the friction plate 68. As a result, the free end 67 of the shaft 15 is twisted at its root and separates from other parts.

In order to prevent the free end 67 of the separated shaft from projecting out of the tubular part 20 of the housing, a metal ring member 82 is arranged coaxially within the tubular part 20.

The ring member 82 is inserted into the tubular portion 20 from its open end, and the step portion 20 formed in the tubular portion 20 is formed.
a. A circumferential groove 84 coaxial with the inner wall of the tubular portion 20 is provided.
Is fitted. The circumferential groove 84 has a width dimension slightly larger than the thickness dimension of the snap ring 86. Circumferential groove 84
The snap ring 86 fitted on the one side is in contact with the ring member 82 on one surface, whereby the ring member 82 is fixed in the tubular portion 20.

Ring member 82 and snap ring 86
Have a larger inner diameter than the diameter of the shaft tip portion 67a, and the shaft tip portion 67a extends through these ring members 82 and snap ring 86. On the other hand, the base portion 67b connected to the tip portion 67a of the shaft has a diameter larger than the inner diameter of the ring member 82. Thus, when the free end 67 of the shaft is torsioned and separated from the other portion, the free end 67 is moved toward the open end of the tubular portion 20 by the ring member 82 at the large-diameter base portion 67b. Movement is prevented and held in the tubular portion 20.

By holding the free end 67 of the torsioned shaft in the tubular portion 20, damage to equipment around the swash plate type compressor 10 in the engine room when the free end 67 is released is prevented. Is done.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a swash plate type compressor of the present invention.

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged sectional view of a tubular portion of a housing, a tip portion of a shaft, and a ring.

FIG. 4 is an enlarged side view of a tubular portion of a housing, a tip portion of a shaft, and a ring.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Swash plate compressor 12 Housing 14 Cylinder block 15 Shaft 16 Swash plate 18 Piston 20 Tubular part 67, 67a, 67b of housing Free end of shaft, tip part and base part thereof 82 Ring member 86 Snap ring

Claims (2)

(57) [Claims] 1. A housing having a main body and a tubular portion, a cylinder block having a plurality of cylinders housed in the main body of the housing, and a free end rotatably supported by the cylinder block and projecting from the cylinder block. A swash plate fixed to the shaft and rotatable together with the shaft, and a piston disposed in each cylinder of the cylinder block and capable of reciprocating in the axial direction of each cylinder, wherein the swash plate And a ring member coaxially disposed and fixed within the tubular portion of the housing, the free end of the shaft having a smaller diameter than the inner diameter of the ring member. And a large diameter base portion, wherein the tip portion penetrates the ring member. 2. The tubular portion of the housing has a circumferential groove provided in an inner wall thereof, and the ring member is fixed to the tubular portion by a snap ring fitted in the circumferential groove and surrounding a tip portion of the shaft. The swash plate compressor according to claim 1, wherein: