JP2000220571A - One-side swash plate type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily increase the number of cylinders. SOLUTION: This one-side swash plate compressor performs a compressing operation only by one side of a piston 8. In this case, a front housing 2, a cylinder block 3 and a cylinder head 4 are connected by a plurality of through-bolts 5, and the cylinder block 3 is provided with a plurality of through-holes 35 for inserting the plurality of through-bolts 5. At least one of the plurality of through-holes 35 has a sectional area larger than that of each through-bolt 5, and the crank chamber 26 of the front housing 2 and the suction chamber 42 of the cylinder head 4 communicate with each other through a gap formed between the through-hole 35 having the sectional area larger than that of the through-bolt 5, and the through-bolt 5.

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 in which a compression operation is performed by only one side of a piston.

[0002]

2. Description of the Related Art In a conventional swash plate type compressor in which a compression operation is performed by only one side of a piston, a front housing,
The cylinder block and the cylinder head are fastened with a plurality of through bolts, and the cylinder block is provided with a plurality of through holes for inserting the plurality of through bolts.

In the single-swash plate type compressor, a discharge path for a refrigerant, that is, a blow-by gas, leaking into a crank chamber from a gap between a cylinder block and a piston when compressing the refrigerant is provided. In the conventional single-swash plate type compressor, as shown in FIG. 4, a dedicated passage 37 is formed in the cylinder block 3 as a discharge path, and the crankcase formed in the front housing 2 is formed by the dedicated passage 37. 26,
It is configured to communicate with a suction chamber 42 formed in the cylinder head 4.

[0004]

There is a tendency that the number of cylinders is increased in response to the reduction in noise required for the compressor, and it is becoming difficult in terms of design to provide the above-described dedicated passage, and the A plan is needed.

Therefore, a first object of the present invention is to provide a single-swash plate compressor capable of easily increasing the number of cylinders.

[0006] Further, oil lubricates each sliding portion in the single swash plate type compressor, but it prevents heat exchange in the heat exchanger. Therefore, it is preferable that a large amount of oil remains in the crank chamber.

Therefore, a second object of the present invention is to solve the first object, and to efficiently discharge oil mixed with the blow-by gas when discharging the blow-by gas in the crank chamber to the suction chamber. Another object of the present invention is to provide a single swash plate type compressor that can be left in a refrigerator.

Further, in the single-swash plate compressor, it is preferable to increase the length of the cylinder bore in order to stabilize the posture of the piston at the bottom dead center. Is required.

[0009] Therefore, a third object of the present invention is to solve the first object and to provide a small and lightweight single-swash plate type compressor.

[0010]

According to the first aspect of the present invention, there is provided a cantilever type compressor in which a compression operation is performed by only one side of a piston, wherein a front housing, a cylinder block, and a cylinder head include a plurality of cylinders. Fastened by through bolts, in the cylinder block, in a single swash plate type compressor provided with a plurality of through holes for inserting the plurality of through bolts, at least one of the plurality of through holes is A crank chamber of the front housing and a suction chamber of the cylinder head having a cross-sectional area larger than a cross-sectional area of the through bolt; A cantilever type compressor characterized by being communicated with through a gap created between the bolt and the bolt.

According to a second aspect of the present invention, in the cantilever type compressor according to the first aspect, at least one of a head gasket disposed between the cylinder block and the cylinder head and the cylinder head. A notch is provided, and the notch, together with the gap, constitutes a communication path for communicating the crank chamber and the suction chamber.

According to the third aspect of the present invention, in the cantilever plate type compressor according to the first aspect, the cylinder block has a substantially ring-shaped projection on an outer peripheral edge of an end surface on a crank chamber side thereof. The inner edge of the contour of the projection when the projection is viewed from the front housing side is substantially the outermost edge of the cylinder bore formed in the cylinder block and the swash plate when viewed from the front housing. A swash plate type compressor having an equal shape and wherein the through-hole penetrates through the projection is obtained.

According to a fourth aspect of the present invention, in the cantilever type compressor according to the third aspect, a part of the inner surface of the projection is partially formed on an inner wall surface of a cylinder bore formed in the cylinder block. As a result, a single-swash plate type compressor is provided which is in sliding contact with a piston slidably inserted into the cylinder bore.

According to a fifth aspect of the present invention, in the cantilever type compressor according to the third or fourth aspect, an end surface of the projection on the front housing side is in contact with an end surface of the front housing via a sealing member. A single-swash plate type compressor is provided, which has a sealing surface for making a seal between the front housing and the cylinder block in contact therewith.

[0015]

In the single-swash plate compressor of the present invention, the crank chamber and the suction chamber communicate with each other through the gap formed between the through-hole and the through-hole having a larger sectional area than the through-bolt. It is not necessary to provide a special dedicated passage for connecting the crank chamber and the suction chamber to the cylinder block as in the related art. For this reason, the degree of freedom in designing the cylinder block is increased, and it is possible to form a larger number of cylinder bores than before.

In a single-swash plate type compressor having a projection on the end face of the cylinder block on the crank chamber side and a through hole penetrating the projection, oil adhering to the end face on the crank chamber side of the cylinder block is removed by the projection. Since the oil is blocked, the oil does not flow along the end face of the cylinder block on the crank chamber side and flows into the through-hole. Therefore, the oil is included in the refrigerant returned to the suction chamber through a gap formed between the through-hole and the through bolt. It is possible to reduce the amount of oil.

Further, in a single-swash plate type compressor in which a part of the inner surface of the projection is a part of the inner wall surface of the cylinder bore, a part of the inner surface of the projection is obtained even if the axial length of the compressor is reduced. Thus, the posture of the piston can be stabilized, so that the size and weight can be reduced more easily than before.

[0018]

FIG. 1 is a longitudinal sectional view of a swash plate type compressor according to a first embodiment of the present invention. Referring to FIG. 1, a single-swash plate type compressor 1 includes a front housing 2
, A cylinder block 3, and a cylinder head 4, which are fastened by a plurality of through bolts 5.

The front housing 2 has a substantially funnel shape, and has a boss 21 at the center thereof.
A plurality of insertion holes 22 for inserting a plurality of through bolts 5 are formed in the outer peripheral portion.

The boss 21 of the front housing 2 includes
The main shaft 6 is inserted so that one end thereof protrudes to the outside. The main shaft 6 is rotatably supported by the front housing 2 at a portion near one end thereof via a needle bearing 23 disposed in the boss portion 21. The space between the main shaft 6 and the boss 21 is sealed by a seal member 24.

A swash plate 7 is mounted on the main shaft 6. The swash plate 7 is thrust supported by the front housing 2 via a thrust needle bearing 25.

The cylinder block 3 is attached to the open end of the front housing 2 and closes the open end of the front housing 2. Thus, a crank chamber 26 is formed in the front housing 2. A ring-shaped projection 31 is formed on the outer peripheral edge of the end surface of the cylinder block 3 on the crank chamber side. The front housing-side end surface of the projection 31 is formed as a seal surface 31a that comes into contact with the opening-side end surface of the front housing 2 with a seal member 32 interposed therebetween to seal between the front housing 2 and the cylinder block 3. Further, a plurality of cylinder bores 33 are formed at predetermined intervals in the cylinder block 3 so as to be adjacent to the inside of the projection 31. A needle bearing 34 is disposed at the center of the cylinder block 3, and the other end of the main shaft 6 is rotatably supported by the cylinder block 3 via the needle bearing 34. Further, a plurality of through holes 3 are formed in the cylinder block 3 so as to be adjacent to the inside of the projection 31 and at the center of the adjacent cylinder bore 33.
5 are formed. These through holes 35 are for passing through bolts 5 passed through the crank chamber 26 through the insertion holes 22 of the front housing 2 to the cylinder head 4. Of the plurality of through holes 35, the through hole 35 below the axis a of the main shaft 6 has a circular cross section and is a normal hole. Of the plurality of through holes 35, the through hole 35 above the axis a of the main shaft 6 has an elliptical cross-sectional shape, and the cross-sectional area is larger than the cross-sectional area of the through bolt 5. (Hereinafter, this through hole is referred to as a communication through hole). Therefore, a gap 3 is provided between the through-bolt 5 and the communication through-hole 35 above the axis a of the main shaft 6.
6, and through this gap 36,
The crank chamber 26 communicates with a suction chamber 42 described later.

A single-headed piston 8 is inserted into a cylinder bore 33 of the cylinder block 3. The single-headed piston 8 has a piston portion 81 and a shoe receiving portion 82 connected to the piston portion 81. Single-headed piston 8
Is configured so that the swash plate 7 is slidably held by a pair of shoes 9 that are swingably disposed in the shoe receiving portion 82, whereby the single-headed piston 8 moves the swash plate 7. When the swash plate 7 rotates, the swash plate 7 reciprocates in the cylinder bore 33.

The cylinder head 4 is disposed on the surface of the cylinder block 3 opposite to the side surface of the crank chamber with the valve plate device 10 interposed therebetween. The cylinder head 4 has a partition wall 41, a suction chamber 42 is formed outside the partition wall 41, and a discharge chamber 43 is formed inside the partition wall 41. Further, a plurality of female screw portions 44 that are respectively screwed with the plurality of through bolts 5 are formed on the outer peripheral portion of the cylinder head 4. Further, a notch 45 that connects the communication through hole 35 and the suction chamber 42 is formed on the outer peripheral portion of the cylinder head 4. In this embodiment, the notch 4
5 and the above-mentioned gap 36 constitute a discharge path for allowing blow-by gas in the crank chamber 26 to escape to the suction chamber 42.

The through bolt 5 has a male screw 5 at its tip.
One. The through bolt 5 is inserted through the insertion hole 22 of the front housing 2 and the through hole 35 of the cylinder block 3, and the male screw portion 51 is screwed into the female screw portion 44 of the cylinder head 4. Thereby, the front housing 2, the cylinder block 3, and the cylinder head 4 are fastened to each other.

In this embodiment, the communication through hole 35 is used.
Are formed in a portion above the axis a of the cylinder block 3, but this communication through hole 35
I just need to get it. On the contrary, all the through holes 35 may be formed as communication through holes.

In this embodiment, the notch 45 is provided in the cylinder head 4. The notch communicating the gap 36 and the suction chamber 42 is provided in the head gasket 101 which is a member of the valve plate device 10. May be formed on the other side, or
It may be formed on both the cylinder head 4 and the head gasket 101.

FIG. 2 is a longitudinal sectional view of a swash plate type compressor according to a second embodiment of the present invention, and FIG. 3 is a sectional view taken along line AA shown in FIG.

Referring to FIG. 2 and FIG. 3, the present embodiment
Since the configuration is substantially the same as that of the first embodiment, the same components as those of the first embodiment or the same components are the same as those of the first embodiment.
The same reference numerals as those in the first embodiment denote the same parts, and a description thereof will be omitted.
Only different parts will be described.

This embodiment is different from the first embodiment in the shape of the projection 31. In the case of the present embodiment, when the projection 31 is viewed from the front housing 2 with the line of sight coincident with the axis a, the inner edge of the contour of the projection 31 is the cylinder bore 3.
3 and the swash plate 7 are connected to the front housing 2
The shape is substantially the same as the outermost peripheral edge of the shape when viewed from the top. In addition, each through hole 35 is
Penetrates. Therefore, the oil adhering to the end surface of the cylinder block 3 on the crank chamber side is blocked by the inner side surface of the projection 31, so that the oil does not flow into the communication through hole 35. As a result, the amount of oil flowing from the crank chamber 26 to the suction chamber 42 can be reduced.

In this embodiment, a part of the inner surface of the projection 31 also serves as a part of the inner wall surface of the cylinder bore 33. As a result, even if the length in the axial direction a of the swash plate type compressor 1 is reduced, the cylinder bore 33 is formed at this portion.
Can be made longer and the attitude of the single-headed piston 8 can be stabilized, so that the size can be reduced more easily than in the past.

Also in this embodiment, the front housing-side end surface of the projection 31 comes into contact with the opening-side end surface of the front housing 2 with the sealing member 32 interposed therebetween, and a seal between the front housing 2 and the cylinder block 3 is formed. Is performed.

[0033]

According to the swash plate type compressor of the present invention, the crank chamber and the suction chamber communicate with each other through the gap between the through-hole and the through hole having a larger cross-sectional area than the cross-sectional area of the bolt. Since there is no need to form a blow-by gas discharge passage in the cylinder block as in the conventional case, the degree of freedom in designing the cylinder block is high,
A cylinder bore can be formed in the cylinder block.

Also, in the case where a projection is provided on the end face of the cylinder block on the crank chamber side, and the projection is made to penetrate through the projection, the amount of oil flowing out of the crank chamber can be minimized by the projection. .

Further, when a part of the inner surface of the projection is formed as a part of the inner wall surface of the cylinder bore, the posture of the piston can be stabilized by a part of the inner surface of the projection. The size of the compressor can be easily reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cantilever type compressor according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a cantilever type compressor according to a second embodiment of the present invention.

FIG. 3 is a sectional view taken along line AA shown in FIG. 2;

FIG. 4 is a longitudinal sectional view of an example of a conventional single swash plate type compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Single swash plate type compressor 2 Front housing 3 Cylinder block 4 Cylinder head 5 Through bolt 6 Main shaft 7 Swash plate 8 Single head piston 9 Shoe 10 Valve plate device 21 Boss 22 Insertion hole 23 Needle bearing 24 Seal member 25 Thrust needle bearing 26 Crank Chamber 31 Projection 31a Sealing surface 32 Sealing member 33 Cylinder bore 34 Needle bearing 35 Through hole 36 Gap 41 Partition wall 42 Suction chamber 43 Discharge chamber 44 Female thread part 45 Notch 51 Male thread part 81 Piston part 82 Shoe receiving part 101 Head gasket

Claims (5)

[Claims] A swash plate type compressor that performs a compression operation by only one side of a piston, wherein a front housing, a cylinder block, and a cylinder head are fastened by a plurality of through bolts, and the cylinder block is In a single-swash plate type compressor provided with a plurality of through holes for inserting through bolts, at least one of the plurality of through holes has a cross-sectional area larger than a cross-sectional area of the through bolt. The crank chamber of the front housing and the suction chamber of the cylinder head communicate with each other through a gap formed between the through-hole having a cross-sectional area larger than the cross-sectional area of the through-bolt and the through-bolt. A single-swash plate compressor. 2. The swash plate type compressor according to claim 1, wherein a notch is provided in at least one of a head gasket disposed between the cylinder block and the cylinder head and the cylinder head, The single-swash plate type compressor, wherein the notch constitutes a communication passage that communicates the crank chamber and the suction chamber together with the gap. 3. The single swash plate type compressor according to claim 1, wherein the cylinder block has a substantially ring-shaped projection on an outer peripheral edge of an end surface on a crank chamber side, and the projection is provided on the front housing side. The inner edge of the contour of the projection when viewed from above has a shape substantially equal to the outermost peripheral edge of the shape when the cylinder bore and the swash plate formed in the cylinder block are viewed from the front housing, The through hole,
A swash plate type compressor characterized by penetrating the projection. 4. The single swash plate type compressor according to claim 3, wherein a part of an inner surface of the projection forms a part of an inner wall surface of a cylinder bore formed in the cylinder block, and is formed in the cylinder bore. A one-side swash plate type compressor characterized in that it comes into sliding contact with a slidably inserted piston. 5. The front swash plate type compressor according to claim 3, wherein an end surface of the projection on the front housing side is in contact with an end surface of the front housing with a sealing member interposed between the front housing and the front housing. A one-side swash plate type compressor having a sealing surface for sealing with a cylinder block.