JPH07127568A - Cylinder head of compressor - Google Patents

Abstract

PURPOSE:To dispense with the combination with other separate members and reduce the number of parts and the wall thickness of a cylinder head by using a core made of the resin having the melting point lower than that of the metal of which the connector part is formed for the connector part for connecting the piping to integrate the core with the cylinder head. CONSTITUTION:In a variable displacement compressor 1 on a wabble plate side, a cylinder block 3 is fixed to the open end of a housing 2, and a crank chamber 4 is formed. A cylinder head 5 is fixed to the other end of the cylinder block 3 across a valve plate 6. In addition, a connector part 15 to connect the piping is arranged at a discharge port 13 to be communicated so at least a high pressure chamber 31 of the cylinder head 5. A core made of the resin having the melting point lower than that of the metal of which the connector part is formed is used for the connector part 15, and integrated with the cylinder head 5. This constitution dispenses with the combination with other separate members, and reduce the number of parts and the wall thickness of the cylinder head 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder head attached to the end of a compressor.

[0002]

2. Description of the Related Art In many cases, the piping connected to a compressor is restricted in the direction in which it is connected to the compressor in order to avoid interference with other parts. Some have a connector for pipe connection that specifies the direction.

There is also a conventional wobble plate type compressor in which a baffle plate is attached to a high pressure chamber formed in a cylinder head in order to reduce high pressure pulsation.

[0004]

However, when the connector and the baffle plate are formed as separate members, in addition to an increase in the number of parts, it is necessary to mold the mounting portion, and the mounting portion has a certain thickness. It was necessary to hold the cylinder head, and it was difficult to reduce the thickness of the cylinder head.

In order to solve this, it is possible to use a sand core to integrally form a connector and a baffle plate at the time of casting the cylinder head, but the sand core is expensive and the product itself is expensive. Become. Further, since it is difficult to completely remove the sand core, if a cooling cycle is assembled using the compressor having this cylinder head, the remaining sand will flow out into the cycle and the reliability will be reduced. There is a defect.

Therefore, an object of the present invention is to solve the above-mentioned inconvenience, reduce the number of parts, reduce the thickness of the cylinder head, and provide an inexpensive and highly reliable cylinder head for a compressor.

[0007]

In the cylinder head of a compressor provided with a connector portion for connecting a pipe, a melting point lower than that of the constituent metals is set. The connector part is integrally cast by using the resin core that it has.

Further, according to a second aspect of the present invention, in a cylinder head of a compressor in which a high-pressure chamber is formed inside and a baffle plate for reducing high-pressure pulsation is provided in the high-pressure chamber, the constituent metal The baffle plate is integrally cast using a resin core having a melting point lower than the melting point.

[0009]

Therefore, according to the first and second aspects of the present invention, since the connector portion and the baffle plate are integrally formed with the cylinder head by using the resin core, the connector portion and the baffle plate are formed in the cylinder head. It is not necessary to secure a connection allowance to provide the cylinder head, and the cylinder head does not need to have an extra thickness.

Further, since the core used for casting is made of resin, the core can be formed at low cost, and in the work of removing the core,
Since the core is melted and removed, and the remaining resin can be dissolved out with a solvent, the core does not remain in the molded product like the conventional sand core, and therefore the above-mentioned object is achieved. Is what you can do.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a wobble plate type variable displacement compressor 1 has a bottomed cylindrical housing 2, and a cylinder block 3 is fixed to the open end of the housing 2 to form the housing 2 and the cylinder block. A crank chamber 4 is formed by being surrounded by one end of the crank chamber 3. A cylinder head 5 is fixed to the other end of the cylinder block 3 with the valve plate 6 interposed therebetween.

The drive shaft 7 is rotatably supported by the housing 2 and the cylinder block 3, and the drive shaft 7 has a thrust flange which is rotatably maintained in the housing 2 via a thrust bearing 8. The rotating member 9 for power transmission is fixed in the crank chamber 4.
A rotary member 11 for supporting a wobble plate 19, which will be described later, is also rotated in the crank chamber 4 via a hinge ball 10 loosely fitted to the drive shaft 7.
It is swingably supported. The supporting rotating member 11 is connected to the power transmitting rotating member 9 via a link mechanism.

The hinge ball 10 includes a first elastic member 16 interposed between the hinge ball 10 and a rotary member 9 for power transmission, and a second elastic member interposed between a receiving plate 17 provided on the drive shaft 7. Both sides are pressed by the member 18 to allow the drive shaft 7 to move in the axial direction.

The wobble plate 19 is rotatably supported in the crank chamber by a rotary member 11 for supporting the wobble plate via radial and thrust bearings 20 and 21, and a slider for the housing 2. It is engaged via 22 and only swinging is allowed with the hinge ball 10 as a fulcrum.

A plurality of pistons 23 (for example, 7 in a 7-cylinder compressor) are connected to the wobble plate 19 via rods 24. These pistons 23
Is slidably inserted into a cylinder bore 25 formed in the cylinder block 3, and a compression chamber is formed in a space surrounded by the end portion of the piston 23, the cylinder bore 25, and the valve plate 6. ing.

The cylinder head 5 includes a valve plate 6
When the piston 23 is in the suction stroke, the low pressure chamber 28 is opened through the suction port 27 formed in the valve plate 6 when the piston 23 is in the suction stroke. The high pressure chamber 3 communicates with the compression chamber, and when the piston 23 is in the discharge stroke, the discharge valve 29 is opened and the discharge port 30 formed in the valve plate 6 is used.
1 communicates with the compression chamber.

The low pressure chamber 28 and the high pressure chamber 31 are respectively connected to the suction port 12 and the discharge port 13 formed in the cylinder head 5, and for connecting the suction port 12 and the discharge port 13 with piping. Connector parts 14 and 15 are provided. The connector portions 14 and 15 are formed integrally with the cylinder head 5 (see FIG. 2), project from the rear surface of the cylinder head 5 and are bent in a predetermined direction, and have a screw for attaching a pipe at a tip thereof. Groove 14a,
15a is formed.

Further, in the high pressure chamber 31, a baffle plate 52 for reducing high pressure pulsation is formed integrally with the cylinder head 5. This baffle plate 52 is
It is provided so as to divide the high pressure chamber 31 into two, and the communication hole 5
These divided spaces are communicated with each other only via 3.

Further, in the compressor 1, a pressure control valve 33 constituting a capacity varying means is inserted and fixed in a control valve insertion hole 34 formed in the cylinder head 5, the valve plate 6 and the cylinder block 3. Then, the control valve insertion hole 3
4 is connected to the crank chamber 4 via a communication passage 35 formed in the cylinder block 3.

The pressure control valve 33 is provided with a high pressure bellows 39 at the rear, and a space 40 formed outside the high pressure bellows 39 is defined behind the high pressure inlet 41 and the pressure adjusting valve 33. It communicates with the high pressure chamber 31 through the space 42 and the high pressure communication passage 43.

The high pressure bellows 39 is attached to a sliding member 44, and a movable member 46, to which one end of a low pressure bellows 45 is fixed, is slidably assembled to the sliding member 44. At the other end of the low pressure bellows 45,
A valve 47 is attached. This low pressure bellows 45
The space 48 formed on the outer side of is communicated with the low pressure chamber 28 via the low pressure inlet 49, the low pressure communication passage 50, and the communication hole 51.

The valve 47 opens and closes the communication between the communication passage 35 and the space 48 outside the low pressure bellows 45. When the valve 47 is opened, the crank chamber 4 has the communication passage 35, the space 48 and the low pressure. The low pressure chamber 28 communicates with the inlet 49, the low pressure communication passage 50, and the communication hole 51.

However, when the load is high and the high pressure is high, the high pressure bellows 39 contracts due to the high pressure introduced into the space 40 from the high pressure chamber 31, and therefore the force pushing the low pressure bellows 45 becomes weak. . Therefore, the valve 47 becomes easy to open, the refrigerant gas blown into the crank chamber 4 pushes open the valve 47 and escapes to the low pressure chamber 28, and the pressure in the crank chamber 4 decreases, so that the back pressure of the piston 23 decreases. The piston stroke increases and the compressor discharge rate increases.

On the other hand, when the load is small and the high pressure is low, the high pressure bellows 39 expands, so that a force is generated in the direction of contracting the low pressure bellows 45, the valve 47 becomes difficult to open, and the crank chamber 4 Refrigerant gas blown into the interior of the crank chamber will accumulate in the crank chamber.
Pressure rises. Therefore, the back pressure of the piston 23 increases, the stroke of the piston decreases, and the discharge amount of the compressor decreases.

The cylinder head 5 is molded by a casting cycle as shown in FIG. That is, in step 100, as shown in FIG. 4, a core 60, which is formed of a suction port, a discharge port, a high-pressure chamber on the discharge port side defined by a baffle plate, etc., is fixed to form the outer shape of the cylinder head. The mold is fixed to the mold 61, and the mold is clamped together with the moving mold 62 that forms the high-pressure chamber and the low-pressure chamber on the valve plate side partitioned by the baffle plate. Here, core 6
0 is made of a resin such as polycarbonate, and its melting point (about 145 degrees) is lower than the freezing point (about 640 degrees) of the molten metal (for example, ADC12) to be pressed into the mold.

Then, the molten metal is pressed into the space between the fixed mold 61 and the movable mold 62, which are assembled, and the resin core 60 (step 200). As shown in FIG. 5, the molten metal is instantly (after ΔT) lowered to the freezing point, and the metal surface is solidified before the temperature of the resin core reaches the melting point due to conduction heat from the molten metal. The product is shaped before it begins to melt. Completely solidify this molten metal (step 3
00), the mold is opened after solidification (step 400),
The cylinder head cast together with the core is extruded and taken out (step 500). Then, the cylinder head 5 is heated together with the resin core 60, and the temperature is set lower than the melting point of the metal forming the cylinder head but higher than the melting point of the resin (step 600) to melt the resin. It is removed from the holes formed in the cylinder head (step 700). Finally, if the remaining resin is completely dissolved with a solvent, the baffle plate 52, the connector portion 14,
The cylinder head 5 in which 15 is integrally formed is completed (step 800).

Before removing the core 60, a step of processing a necessary portion may be added. If the core is melted out after such processing, there is also an advantage that chips generated during processing can be discharged at the same time.

Therefore, according to the casting using the resin core,
If the core is heated and melted, and the remaining resin is melted out with a solvent, the resin can be removed without remaining in the cylinder head 5, so cooling is performed using a compressor having such a cylinder head. Even if you assemble the cycle,
The resin does not flow out during the cooling cycle. Further, since it is not necessary to separately attach the connector portions 14 and 15 and the baffle plate 52 to the cylinder head 5, it is not necessary to form a connection margin which is necessary when these are attached later, and the cylinder head can be made thinner. It is possible to reduce the number of components of the compressor itself.

In this embodiment, the connector portion 1
The cylinder head 5 includes the baffle plate 52 and the baffle plate 52.
Although it is shown that it is integrally formed with the connector part 1,
Either one of 4, 5 and the baffle plate 52 may be formed integrally with the cylinder head by using a resin core.

[0031]

As described above, according to the first and second aspects of the present invention, since the connector portion and the baffle plate are integrally formed with the cylinder head by the resin core, the cylinder head can be formed as a separate member. Since it is not necessary to form them in combination, the number of parts can be reduced. Further, it is not necessary to secure a connection allowance for another member, and the cylinder head can be made thin.

Furthermore, since the core used for casting is made of resin, the cylinder head integrally formed with the baffle plate and the connector portion can be easily formed without leaving the core, and it is inexpensive and reliable. It is possible to provide a high compressor cylinder head.

[Brief description of drawings]

1 is a cross-sectional view showing an embodiment of a wobble plate type variable displacement compressor, and a cylinder head attached to an end of the compressor has an end surface cut along line AA of FIG. It is a figure.

FIG. 2 is a view of the cylinder head of the compressor shown in FIG. 1 as viewed from the outside (right side in the drawing).

FIG. 3 is a flowchart showing a casting cycle of a cylinder head.

FIG. 4 is a cross-sectional view showing a die casting mold and a resin core used for casting a cylinder head.

FIG. 5 is a temperature curve of the metal forming the cylinder head,
It is a characteristic diagram which shows the temperature curve of a resin core.

[Explanation of symbols]

 1 Wobble plate type variable displacement compressor 3 Cylinder block 5 Cylinder head 14, 15 Connector part 52 Baffle plate 60 Resin core

Claims (2)

[Claims] 1. A cylinder head of a compressor provided with a connector for connecting a pipe, wherein the connector is integrally cast using a resin core having a melting point lower than that of the constituent metal. Cylinder head of a compressor. 2. In a cylinder head of a compressor in which a high-pressure chamber is formed and a baffle plate for reducing high-pressure pulsation is provided in the high-pressure chamber, a resin core having a melting point lower than that of constituent metals is used. A cylinder head for a compressor, wherein the baffle plate is integrally cast.