JPS6332992B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention involves meshing a pair of spiral bodies at different angles, and applying relative circular motion (only orbital motion) to move the sealed space formed between the spiral bodies toward the center. The present invention relates to a positive displacement fluid compression device, a so-called scroll compressor, which discharges compressed fluid from the center by reducing its volume while moving.

The principle of such a scroll compressor has been known for a long time.

Referring to FIG. 1, when the two spiral bodies 1 and 2 are arranged at different angles and interlocked with each other, there is a contact area between the two spiral bodies 1 and 2 as shown in the figure. A confined space 3 is formed extending from the contact portion. Now, with respect to one spiral body 1 and the other spiral body 2, the center o' of one spiral body 1 revolves around the center o of the other spiral body 2 with a radius o-o'. When the spiral body 1 is moved while inhibiting its rotation, the space 3 limited by the sliding movement of both spiral bodies gradually decreases its volume and moves toward the center of the spiral. .

From the state shown in Figure 1a, the revolution angle of the spiral body 1 is
1b, which shows 90°, FIG. 1c, which shows 180°, and FIG. 1d, which shows 270°, it will be understood that the volume of space 3 is gradually reduced. At a point a rotated by 360 degrees, both spaces move to the center and connect with each other, and as shown in FIG. becomes. During this time, the outer space that began to open in Figure 1b moves from Figures 1c and d to Figure 1a, creating a sealed space that takes in new fluid.

Therefore, if sealed disc-shaped side plates are provided at both axial ends of the spiral bodies 1 and 2, and a discharge hole as shown by 4 in Fig. 1 is provided in the center of one side plate, the diameter can be reduced. The fluid taken in on the outside is compressed and discharged from the discharge hole 4.

A general scroll type compressor based on the above-mentioned principle is well known and is disclosed, for example, in Japanese Patent Application Laid-open No. 32512/1983.

Incidentally, a scroll type compressor has a property that the contact state of the side walls of both spiral coils during sliding is close to a line contact, and the contact pressure is higher than that of other types of compressors. For this reason, when the compressor is operating, the lubricating oil film runs out on the sliding parts more frequently than with other types of compressors, and this is especially true when the compressor is operated at high loads and low rotations. The frequency is increasing.

For this reason, in order to make the compressor lighter and smaller, both scroll members were made of aluminum.
If the sliding surfaces of both members are made of soft aluminum, if the contact pressure increases to the extent that oil film breaks during compressor operation, both members will deform and stick together at the contact area, causing both members to There was a problem that the sliding surface of the scroll member was seized.
In addition, if the sliding surfaces of both scroll members made of aluminum are treated with a hard coating, then on the contrary, since they are both hard, it becomes difficult for both members to deform at the contact area, and furthermore, the contact pressure increases, causing the mutual contact to occur. Scratch-like flaws occur, and pieces of the hard coating created by the scratches are interposed between the sliding surfaces of each other, thereby accelerating wear.

Therefore, in the present invention, both the spiral bodies, the first scroll member having the spiral body fixed on one surface of the plate and the second scroll member having the spiral body fixed on one surface of the plate, are mutually connected. The first scroll member is rotated on a circular orbit with the side walls of both spiral windings deviated by 180 degrees and arranged so that they are in contact with each other, thereby forming a closed space between both spiral winding bodies and flowing fluid. is taken in, and as the first scroll member moves,
In a scroll type compressor for automobile air conditioning, which is moved around the space and performs a unidirectional fluid compression action with a reduction in volume, the first scroll member and the second scroll member are made of aluminum. The sliding surface of only one of the first scroll member and the second scroll member is subjected to hard alumite treatment, and the sliding surface of the other scroll member is made of aluminum. We have obtained a scroll-type compressor for automobile air conditioning which is characterized by: According to this, since the sliding surface of the other scroll member is made of aluminum and is softer than the sliding surface of one scroll member that has been subjected to hard alumite treatment, the sliding surface of one scroll member that has been subjected to hard alumite treatment It becomes possible for the sliding surface of the other scroll member to deform and slide on the moving surface so as to absorb the contact pressure, reducing the frequency of oil film failure.
The above-mentioned problem does not occur.

As can be seen from its configuration, a scroll compressor performs orbital motion with a small orbital radius, so
Compared to other compressors such as reciprocating type compressors, its sliding speed is extremely low, which gives it advantageous wear resistance properties. Therefore, even with the means shown in the present invention, sufficient wear resistance can be obtained. Of course, a low sliding speed is detrimental to the formation of an oil film on the sliding surface, but overall, a low sliding speed is advantageous in terms of wear resistance. These conditions were set assuming the service life of the compressor as shown below. Compressor rotation speed 1200 rpm Discharge gas pressure 26-28 Kg/cm ² G Suction gas pressure 3-4 Kg/cm ² G Continuous operation time 400 hr. and Compression Machine rotation speed: 800 rpm Discharge gas pressure: 14 Kg/cm ² G Suction gas pressure: 1 Kg/cm ² G Continuous operation time: 500 hr. After the test, the compressor was disassembled and both scroll members were examined for wear, but there was almost no wear. This is supported by the fact that it has not progressed, and that even after the test, there was only a slight decrease in ability.

The present invention will be explained below with reference to drawings showing embodiments.

FIG. 2 is a central sectional view showing the structure of an embodiment of the present invention. The housing 10 consists of a front end plate 11, a rear end plate 12, and a cylindrical side wall 13 connecting them. The fluid inlet 121 and fluid outlet 122 formed form a sealed chamber communicating with the outside.

A main shaft 15 is disposed through the front end plate 11 and rotatably supported thereon via a radial bearing 14 . Further, a main shaft lead-out cylinder 16 protrudes from the outer end surface of the front end plate 11 to the front so as to surround the main shaft 15.
A seal pocket portion 18 in which a shaft seal mechanism 17 is disposed is formed inside, and a driving force transmission device 19 for transmitting an external driving force to the main shaft 15 is rotatably disposed outside the main shaft lead-out cylinder 16.

A rotor 20 is fixed to the inner end of the main shaft 15, and the rotor 20 is supported by a thrust bearing 21 provided concentrically with the main shaft 15 on the inner surface of the front end plate 11. A shaft (crank pin) 22 protruding from the rotor 20 and eccentric from the main shaft 15 is provided on the end surface of the rotor 20 on the side opposite to the front end plate 11 .

Reference numerals 23 and 24 denote a pair of scroll members disposed inside the housing 10, which are made of aluminum to reduce weight and size. While fixing the spiral body 232,
An annular projection 233 with an axial round hole is formed on the opposite surface, and a crank pin 22 having a radial bearing 25 installed on the outer periphery is fitted into the annular projection 233 in the axial round hole, As a result, the movable scroll member 23 is supported by bearings on the crank pin 22.

A flange body 26 having a radially expanding flange surface is disposed on the outside of the annular protrusion 233 of the movable scroll member 23, and the flange body 26 is provided with a flange surface that extends in the radial direction.
It is supported by a thrust bearing 27 provided concentrically with the crank pin 22 on the opposing surface of the crank pin 22 .

Therefore, the crank pin 22 due to the rotation of the main shaft 15
Due to the eccentric movement of the movable scroll member 23,
It performs eccentric movement together with the flange body 26. That is, it moves on a circular orbit whose radius is the distance between the main shaft 15 and the crank pin 22. During the circular orbit movement of the movable scroll member 23, in order to prevent the movable scroll member 23 from rotating, the cylindrical side wall 13 of the housing 10 is provided between the disk-shaped side plate 231 of the movable scroll member 23 and the flange body 26. A rotation prevention mechanism 28 installed on the inner surface is provided.

The fixed scroll member 24 has a disc-shaped side plate 24
A spiral body 242 is fixed on one surface of the spiral body 242, and a through hole 243 corresponding to the discharge hole shown by 4 in FIG. It is set up. Also, the disc-shaped side plate 24
An annular projection 244 is formed on the back surface of the device 1 so as to surround the through hole 243.

On the other hand, an annular protrusion 123 is provided on the inner surface of the rear end plate 12 and protrudes from a position surrounding the opening of the discharge port 122. The outer diameter of the protrusion 123 is formed to be slightly smaller than the inner diameter of the protrusion 244 of the disc-shaped side plate 241, and the protrusion 123
A recessed portion 124 is formed on the outer surface of the recessed portion 1.
An annular elastic body 29 is disposed within 24. This annular elastic body 29 seals between the protrusions of the rear end plate 12 and the scroll member 24, and the annular protrusion 1
23 through the fluid outlet 122 and the scroll member 2
The discharge chamber 30 communicates with the through hole 243 of No. 4.

Note that a notch is partially provided at the peripheral edge of the disc-shaped side plate 241, and the protrusion 131 protruding from the inner surface of the cylindrical side wall 13 is coupled to the notch to form the fixed scroll member 2.
4 rotation stopper.

Then, the sliding surface of the movable scroll member 23 made of aluminum is subjected to hard alumite treatment to form an ultra-hard oxide film on the aluminum surface to improve surface hardness. Note that the sliding surface of the fixed scroll member 24 instead of the movable scroll member 23 may be subjected to hard alumite treatment.

According to the above configuration, if the main shaft 15 is rotated by an external drive via the driving force transmission device 19,
The eccentric movement of the crank pin 22 causes the scroll member 23 to move on a circular orbit. At this time, due to the function of the rotation prevention mechanism 28, the scroll member 23
Since the rotation of the scroll member 23 is prevented, the action of the scroll member 23 on the scroll member 24 becomes as shown in FIG. The fluid is discharged from the hole 243 into the discharge chamber 30 , is discharged from the housing 10 through the fluid outlet 122 , and is circulated through the cooling system, for example, to the fluid inlet 121 .
Return to the inside of the housing 10.

At this time, the fixed scroll member 24
The movable scroll member 23 is urged by the gas pressure in the axial direction, so that it is pressed against the movable scroll member 23, and a sealing force is applied between the disc-shaped side plates of both scroll members and the end of the spiral body.

Further, the seal at the line contact portion between the spiral bodies 232 and 242 is determined by the radius of the circular orbital movement of the scroll member 23, that is, the distance between the main shaft 15 and the crank pin 22,
It will be determined by the pitch of the spiral body.

Now, here, of both scroll members made of aluminum, the sliding surface of the fixed scroll member 24 is left as an aluminum base material, and only the sliding surface of the movable scroll member 23 is hard alumite treated, so the hard alumite treatment is The sliding surface of the fixed scroll member 24 is made of aluminum and is softer than the sliding surface of the movable scroll member 23 which has been treated with alumite. This allows the sliding surfaces to deform and slide to absorb contact pressure, reducing the frequency of oil film failure, preventing seizures due to adhesion between sliding surfaces, and progression of wear on the sliding surfaces. can be prevented and good sealing performance can be obtained.

As described above, the present invention provides a scroll type compressor for automobile air conditioning, in which the first scroll member and the second scroll member are made of aluminum, and one of the first scroll member and the second scroll member is made of aluminum. Hard alumite treatment was applied to the sliding surface of only one scroll member, and the sliding surface of the other scroll member was made of aluminum, so both scroll members were made of aluminum in order to make the compressor lighter and more compact. However, seizure due to adhesion between the sliding surfaces of both scroll members,
Progress of wear on the sliding surfaces can be prevented and good sealing performance can be obtained.

[Brief explanation of drawings]

Figures 1 a to d are diagrams for explaining the compression principle of the scroll compressor according to the present invention, a to d are diagrams showing states at different angular positions, and Figure 2 is a diagram showing an embodiment of the present invention. FIG. 2 is a central sectional view of the scroll compressor shown in FIG. 1, 2... Spiral body, 3... Closed space, 4...
Discharge hole, 10...Housing, 11...Front end plate, 12...Rear end plate,
13... Cylindrical side wall, 14, 25... Radial bearing, 15... Main shaft, 16... Main shaft lead-out cylinder, 17...
...shaft seal mechanism, 19 ... driving force transmission device, 20 ... rotor, 21, 27 ... thrust bearing, 22 ... crank pin, 23, 24 ... scroll member, 26 ... flange body, 28 ... rotation prevention Mechanism, 29... annular elastic body, 30... discharge chamber.

Claims (1)

[Claims] 1. Both the spiral bodies of the first scroll member having the spiral body fixed on one side of the plate and the second scroll member having the spiral body similarly fixed on one side of the plate are shifted by 180 degrees from each other, In a state in which the side walls of both spiral winding bodies are arranged so as to be in contact with each other, the first scroll member is caused to revolve on a circular orbit to form a closed space between both spiral winding bodies and take in fluid. A scroll type compressor for automobile air conditioning is configured to move around the space as the first scroll member moves, and perform a unidirectional fluid compression action with a reduction in volume. The scroll member and the second scroll member are formed of aluminum, and only one of the first scroll member and the second scroll member is subjected to hard alumite treatment on its sliding surface, and the other scroll member is made of aluminum. A scroll type compressor for automobile air conditioning, characterized in that the sliding surface is made of aluminum.