JP2002180960A - Compressor for thermo-compression type refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-size compressor for a thermo-compression type refrigerating machine capable of reducing the weight having a pressure resistance necessary for a cylinder head. SOLUTION: The cylinder head 14 is so formed that a head inner wall member 23 regulating a delivery chamber 22 is surrounded with a head outer wall member 25 and a suction chamber 24 is formed between the head inner wall member and the head outer wall member. the head inner wall member is connected to the head outer wall member by connecting bolts 26. The head inner wall member is made of a material having the pressure resistance higher than that of the head outer wall member, for example, a steel based material. The head outer wall member is preferably made of an aluminum based material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a compressor for a vapor compression refrigerator.

[0002]

2. Description of the Related Art Refrigeration cycles or refrigerators are used in various fields such as air conditioners for vehicles. Usually, R134 is used as the refrigerant in the refrigerator. This type of refrigerant does not need to be compressed to high pressure. For this reason, a general compressor for refrigerators is made lighter by making as many parts as possible of aluminum-based material.

Recently, in order to prevent global warming, it has been proposed to use CO ₂ as a refrigerant for a refrigerator of a vehicle air conditioner. A compressor of a refrigerator using CO ₂ is called a compressor for a vapor compression refrigerator.

[0004] Like a general refrigerator compressor,
The compressor for a vapor compression refrigerator also includes an integrally formed cylinder head having a suction chamber and a discharge chamber.
In operation, the CO ₂ and sucked through the suction chamber, also discharges of CO ₂ through the discharge chamber. Therefore, during operation, the pressure in the discharge chamber becomes higher than the pressure in the suction chamber.

[0005]

In particular, a compressor for a vapor compression type refrigerator requires a higher operating pressure than a general compressor for a refrigerator, so that the pressure in the discharge chamber during operation is extremely high. Inevitable. For this reason, it is necessary to increase the pressure resistance of the cylinder head.

However, when the integrally formed cylinder head is made of an aluminum-based material, it must be made thick, so that the size of the compressor increases. When it is made of an iron-based material, it is inevitable. There is a problem that the weight of the compressor increases.

An object of the present invention is to provide a compact and lightweight compressor for a vapor compression refrigerator having a pressure resistance required for a cylinder head.

[0008]

According to the present invention, there is provided a compressor for a vapor compression refrigerator having a cylinder head forming a suction chamber and a discharge chamber having a higher pressure than the suction chamber. A head inner wall member defining the discharge chamber, a head outer wall member surrounding the head inner wall member and defining the suction chamber around the head inner wall member, and coupling means connecting the head inner wall member to the head outer wall member And wherein the head inner wall member is made of a material having higher pressure resistance than the head outer wall member, thereby obtaining a compressor for a vapor compression refrigerator.

The head inner wall member may be made of an iron-based material, and the head outer wall member may be made of an aluminum-based material.

[0010] The head inner wall member may have any one of a dome shape, a hemispherical shape, a conical shape, and a box shape.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a compressor for a vapor compression refrigerator according to a first embodiment of the present invention will be described.

The compressor for a vapor compression refrigerator shown in FIG. 1 is of a so-called fixed capacity swash plate type compressor, and includes a cylinder block 11 and a front housing 12 in contact with the front end of the cylinder block 11. , A cylinder head 14 disposed at the rear end of the cylinder block 11 via a valve plate 13. Cylinder block 11, front housing 12, valve plate 1
3 and the cylinder head 14 are fastened and fixed in the axial direction by fastening means such as fastening bolts 15. The cylinder block 11 and the front housing 12
Are all made of aluminum wool material.

The cylinder block 11 has a plurality of cylinder bores 16 formed around a central axis. Each cylinder bore 16 extends axially and has a piston 17
Are slidably inserted in the axial direction.

The valve plate 13 has a suction port 18 and a discharge port 19 corresponding to each cylinder bore 16. A suction port 18 is provided between the valve plate 13 and the cylinder block 11.
A suction valve (not shown) is provided opposite to the suction valve. A discharge valve (not shown) facing the discharge port 19 is provided between the valve plate 13 and the cylinder head 14. Further, a retainer 21 facing the discharge valve is fixed to the valve plate 13. Valve plate 13, suction valve, discharge valve, and retainer 21
Are pre-assembled as a valve plate assembly.

The cylinder head 14 includes a head inner wall member 23 defining a discharge chamber 22, and a head outer wall member 25 surrounding the head inner wall member 23 and defining a suction chamber 24 around the head inner wall member 23. The head outer wall member 25 is fastened and fixed by the fastening bolt 15.
The head inner wall member 23 is connected to the head outer wall member 25 by connecting bolts 26. The head inner wall member 23 and the head outer wall member 25 are positioned with respect to each other by uneven fitting, and an O-ring 27 for sealing extending around the coupling bolt 26 is interposed between them.

Thus, the suction chamber 24 is formed in the periphery of the cylinder head 14, and the discharge chamber 22 is formed in the center. The suction port 18 communicates with a suction chamber 24. The discharge port 19 communicates with the discharge chamber 22. Although not shown, a suction port and a discharge port are connected to the suction chamber 24 and the discharge chamber 22, respectively.

The head inner wall member 23 is a head outer wall member 25.
It is made of a material with higher pressure resistance. That is,
The head inner wall member 23 is made of an iron-based, for example, stainless steel material, and the head outer wall member 25 is made of an aluminum-based material. The head inner wall member 23 and the head outer wall member 25 can be formed by pressing or cutting.

A main shaft 31 extending on a central axis is supported by the cylinder block 11 and the front housing 12 so as to be rotatable and not to move in the axial direction. Spindle 3
A swash plate 32 inclined at a predetermined angle is fixed to 1. A shoe 3 is provided on both sides in the axial direction of the peripheral portion of the swash plate 32.
The piston 17 is axially engaged via 3 and 34. The shoes 33 and 34 are held by the piston 17 and are slidable with respect to the swash plate 32. Main shaft 31, swash plate 3
2, and the shoes 33 and 34 together form a drive mechanism.

When the main shaft 31 is driven to rotate, the swash plate 32 also rotates together with the main shaft 31. In accordance with the rotation of the swash plate 32, the piston 17 is driven via the shoes 33 and 34 and reciprocates in the cylinder bore 16. According to the reciprocating motion of the piston 17, CO ₂ is converted into a refrigerant gas in the suction chamber 24.
It is sucked into the cylinder bore 16 through the suction port 18, compressed and discharged to the discharge chamber 22 through the discharge port 19. When the piston 17 moves to the vicinity of the top dead center, the refrigerant gas is compressed in the cylinder bore 16 to have a considerably high pressure, and is discharged to the discharge chamber 22. As a result, the discharge chamber 22 has an extremely high pressure as compared with the suction chamber 24.

According to the above-described vapor compression refrigerator compressor, the head inner wall member 23 defining the discharge chamber 22 can be made relatively thin because it is made of a material having high pressure resistance, and can be made high pressure without fear of increasing the size. I can stand it. Further, since the head outer wall member 25 is made of an aluminum-based material, an increase in weight is small. Moreover, the head outer wall member 2
Since only the pressure of the suction chamber 24 is applied to 5, it is not necessary to form this portion thick, and there is little fear that the size and weight of the head outer wall member 25 increase. Therefore, it is possible to provide a compact and lightweight vapor compression refrigerator compressor having a pressure resistance required for the cylinder head.

As shown in FIGS. 2A to 2D, the head inner wall member 23 can be formed in various shapes. (A) shows a dome-shaped head inner wall member 23a, (b) shows a hemispherical head inner wall member 23b, (c) shows a conical head inner wall member 23c, and (d) shows a box-shaped head. The inner wall member 23d is shown.

In the above description, the fixed displacement type swash plate type compressor has been described as an example. However, it is needless to say that the present invention can be similarly applied to a so-called variable displacement type swash plate type compressor and other various types of compressors. .

[0023]

As described above, according to the present invention,
It is possible to provide a compact and lightweight compressor for a vapor compression refrigerator having a pressure resistance required for a cylinder head.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a compressor for a vapor compression refrigerator according to a first embodiment of the present invention.

2 (a) to 2 (d) are cross-sectional views showing various examples of the shape of a head inner wall member used in the vapor compression refrigerator compressor of FIG. 1. FIG.

[Explanation of symbols]

 Reference Signs List 11 cylinder block 12 front housing 13 valve plate 14 cylinder head 15 bolt 16 cylinder bore 17 piston 18 suction port 19 discharge port 21 retainer 22 discharge chamber 23 head inner wall members 23a to 23d head inner wall member 24 suction chamber 25 head outer wall member 26 coupling bolt 31 Spindle 32 Swash plate 33, 34 Shoe

Claims (6)

[Claims] 1. A vapor compression refrigerator compressor having a cylinder head forming a suction chamber and a discharge chamber having a higher pressure than the suction chamber, wherein the cylinder head is a head inner wall member defining the discharge chamber. A head outer wall member surrounding the head inner wall member and defining the suction chamber around the head inner wall member; and coupling means connecting the head inner wall member to the head outer wall member, wherein the head inner wall member is A compressor for a vapor compression refrigerator, wherein the compressor is made of a material having higher pressure resistance than a head outer wall member. 2. The compressor according to claim 1, wherein the inner wall member of the head is made of an iron-based material, and the outer wall member of the head is made of an aluminum-based material. 3. The compressor according to claim 1, wherein the inner wall member has a dome shape. 4. The compressor for a vapor compression refrigerator according to claim 1, wherein the head inner wall member has a hemispherical shape. 5. The compressor according to claim 1, wherein the inner wall member has a conical shape. 6. The compressor for a vapor compression refrigerator according to claim 1, wherein the head inner wall member has a box shape.