JPH10288170A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out revolving motion favourable in balance by making the whole of a back pressure chamber on the back surface of a revolving scroll intermediate pressure, taking a thrust receiving surface on the bearing side and restraining a bouncing phenomenon of the revolving scroll. SOLUTION: This compressor is constituted by providing a throttle mechanism 9a on the outlet side of a lubricating oil delivery passage, providing a first ring groove 8a on a bottom surface of a crankshaft 8 on a pressure welded surface of a bearing 11 and the crankshaft 8, forming a first back pressure chamber 13a between a back surface central part of a revolving scroll end plate 6a and the bottom surface of the crankshaft 8 and forming a second back pressure chamber 13b between a back surface outer peripheral part of the end plate 6a of the revolving scroll 6 and the bearing 11. Thereafter, it is constituted to communicate the first back pressure chamber 13a and the second back pressure chamber 13b to each other by forming a second ring groove 11a and an outer groove directed outside on an outer periphery of the first back pressure chamber 13a between a back surface of the end plate 6a of the revolving scroll 6 and the bearing 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly, to a structure for widening a thrust receiving surface and suppressing a dance phenomenon of an orbiting scroll.

[0002]

2. Description of the Related Art A conventional scroll compressor will be described with reference to FIG. 7 which is a longitudinal sectional view thereof, and FIG. The scroll compressor is a sealed container 1
An electric motor 2 and a compression unit 3 are built therein, and the compression unit 3 is mainly constituted by a fixed scroll 4, an orbiting scroll 6, an Oldham ring 7 ', a crankshaft 8', an eccentric bearing 14, a bearing 11 ', and a shaft 10. I have. In this configuration, a spiral fixed scroll wrap 4b is integrally formed on a fixed head plate 4a, and the fixed scroll 4 fixed to a bearing 11 ', a spiral scroll scroll wrap 6b on a swivel head plate 6a, and an orbital drive to the back. Axis 6c
And the orbiting scroll 6 integrally formed with the orbiting scroll wrap 6b inside to form a plurality of compression chambers 5.

[0003] When the electric motor 2 rotates, the Oldham ring 7 is attached to the orbiting scroll 6 by the orbiting drive shaft 6c via an eccentric bearing 14 fitted on a crankshaft 8 'formed on the shaft 10 mounted on the bearing 11'. 'To make a turning motion while preventing rotation. The low-pressure refrigerant sucked into the compression section 3 from the suction pipe 15 by the orbiting motion of the orbiting scroll 6 is compressed while moving sequentially from the outer periphery to the center of the compression chamber 5 to become a high-pressure refrigerant, and is discharged from the discharge port 16 to the discharge chamber 17. The air is discharged from the discharge pipe 19 to the outside through the passage 18 and between the compressor 3 and the electric motor 2.

[0004] Also, a detaching force for pushing up the orbiting scroll 6 is acted on by the refrigerant pressure which has risen at the center of the compression chamber 5, and the fixed end plate 4a, the orbiting scroll wrap 6b and the orbiting end plate are turned.
In order to prevent a gap from being formed between the fixed scroll wrap 6a and the fixed scroll wrap 4b and causing a gas leak to lower the compression efficiency,
The high-pressure refrigerant is introduced between the center of the rear surface of 6a and the upper surface of the crankshaft 8 ', and the high-pressure portion 20 is provided.
13 'is provided, and a tip seal 8a' for preventing leakage of the high-pressure refrigerant is provided on the press-contact surface of the bearing 11 'in the middle thereof. Compression chamber 5 against force
The airtightness is maintained.

However, when the operation is started in a state where the refrigerant pressure on the suction side and the refrigerant pressure on the discharge side are almost equal, the pressure in the compression chamber 5 first increases, and then the pressure in the sealed container increases from the discharge chamber 17, so Out of balance.
At this time, the turning force transmitted from the crankshaft 8 'acting on the turning drive shaft 6c is divided into a force rotating orthogonally to a force pressing the orbiting scroll wrap 6b in the turning radius direction,
The point of reaction of the pressing force is the orbiting scroll wrap 6b constituting the compression chamber 5, and the point of action (right arrow) and the point of reaction (left arrow) are separated in the axial direction of the orbital drive shaft. It will act and cause a tilt.

[0006] For this reason, a dancing phenomenon occurs in the revolving head plate, and gas leakage occurs in the compression chamber to lower the compression efficiency.
There has been a problem that abnormal sliding occurs in each sliding portion and uneven wear of the tip seal occurs. Further, the thrust force for suppressing the dancing phenomenon depends on the area of the high-pressure portion 20 to which the high-pressure load is applied.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and the whole back pressure chamber on the back of the orbiting scroll is set to an intermediate pressure, the thrust receiving surface on the bearing side is widened, and the orbiting scroll dances. It is an object of the present invention to provide a scroll compressor capable of performing a well-balanced orbiting motion.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and comprises an electric motor and a compression unit arranged vertically in a sealed container, and the compression unit is provided with a spiral wrap around a head plate. A orbiting scroll that meshes with the fixed scroll to form a plurality of compression chambers, and supports a orbital drive shaft of the orbiting scroll and forms a crankshaft at the lower end to orbitally drive the upper and lower ends. In a scroll compressor including a shaft having a lubricating oil passage extending therethrough and a bearing that supports the crankshaft, a throttle mechanism is provided at an outlet side of the lubricating oil passage, and the bearing and the bearing A first annular groove is provided on the bottom surface of the crankshaft of the pressure contact surface with the crankshaft, a tip seal is fitted into the first annular groove, and a first annular groove is provided between the center of the rear surface of the orbiting scroll head plate and the crankshaft bottom surface. A back pressure chamber is formed, and a second back pressure chamber is formed between the outer peripheral portion of the back surface of the orbiting scroll head and the bearing, and the first back pressure chamber is formed between the back surface of the orbiting scroll head and the bearing. A second annular groove and an outer groove directed outward are formed on the outer periphery of the back pressure chamber, and the first back pressure chamber and the second back pressure chamber are connected to each other.

Further, the center of the first annular groove coincides with the center of the rotation axis of the orbiting scroll.

The first annular groove has a substantially U-shaped cross section.

Further, the second annular groove and the outer groove are formed on the bottom surface of the bearing.

Further, the second annular groove and the outer groove are formed on the back surface of the orbiting scroll head plate.

Further, an electric motor and a compression section are arranged vertically in a sealed container, and the compression section is provided with a fixed scroll having a spiral wrap on a head plate, and a plurality of compression chambers meshed with the fixed scroll. The orbiting scroll to be formed, an Oldham ring for preventing the orbiting scroll from rotating, and a lubricating oil supply passage that supports the orbiting drive shaft of the orbiting scroll and forms a crankshaft at the lower end to orbitally drive and penetrates from the upper end to the lower end. In a scroll compressor composed of a shaft formed with a shaft and a bearing that supports the crankshaft, a first back pressure chamber is formed between a center of the back surface of the orbiting scroll head plate and the bottom surface of the crankshaft. Forming a second back pressure chamber between the outer peripheral portion of the back surface of the end plate of the orbiting scroll and the bearing, between the intermediate portion of the back surface of the end plate of the orbiting scroll and the bearing, A bi-annular groove, an outward groove facing outward, and an inner groove facing inward were formed, the Oldham ring was fitted into the second annular groove, and the first back pressure chamber and the second back chamber were communicated. It has a configuration.

Further, the second annular groove, the outer groove and the inner groove are formed on the bottom surface of the bearing.

[0015]

According to the above construction, the entire back pressure chamber on the back side of the orbiting scroll is set to the intermediate pressure, the thrust receiving surface on the bearing side is widened, and the dancing phenomenon of the orbiting scroll is suppressed.
A scroll compressor that can perform well-balanced orbiting motion.

[0016]

Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view of a scroll compressor showing one embodiment of the present invention, FIG. 2 is an enlarged sectional view of a main part thereof, and FIG. 4 is a view of the bearing portion of FIG. 2 as viewed from the bottom. In the figure, an electric motor 2 and a compression unit 3 are arranged vertically in a sealed container 1, and the compression unit 3 is engaged with the fixed scroll 4 in a spiral shape and the fixed scroll 4 to form a plurality of compression chambers 5. The orbiting scroll 6 to be formed, the Oldham ring 7 for preventing the orbiting scroll 6 from rotating, and the orbiting drive shaft 6c of the orbiting scroll 6 formed with the crankshaft 8 at the lower end to orbitally drive and penetrate from the upper end to the lower end. A scroll compressor is constituted by a shaft 10 having a lubricating oil passage 9 and a bearing 11 which supports the crankshaft 8.

In this configuration, the fixed scroll plate 4a is formed integrally with the fixed end plate 4a, and the fixed scroll 4 is pressed against the bearing 11, the swirl-shaped turning scroll wrap 6b is fixed to the turning end plate 6a, and the back surface. And a revolving scroll 6 integrally formed with a revolving drive shaft 6c and a revolving scroll wrap 6b
Are engaged with each other to form a plurality of compression chambers 5.

A throttle mechanism 9a having a hole diameter corresponding to a required supply amount of lubricating oil is provided at a lower outlet side of the lubricating oil supply passage 9, and a pressing contact surface between the bearing 11 and the crankshaft 8 has the same crankshaft. A first annular groove 8a is provided on the bottom of
A chip seal 12 is fitted into the compression chamber 5 to shut off the pressure in the compression chamber 5 and the pressure in the compressor.

A first back pressure chamber 11a is formed between the center of the back surface of the orbiting end plate 6a of the orbiting scroll 6 and the bottom surface of the crankshaft 8, and between the outer peripheral portion of the back surface of the orbiting end plate 6a and the bearing 11. A second back pressure chamber 13b is formed in the
On the outer periphery of the first back pressure chamber 13a between the rear surface of the first back pressure chamber 13a and the outer periphery of the bearing 11, a second annular groove 11a into which oil and pressure flow and an outer groove 11b directed outward are formed, and the first back pressure chamber 13a and the A groove (not shown in the direction of the solid line arrow in FIG. 2) through which fluid flows is formed in the press contact surface 6d of the revolving head plate 6a and the fixed head plate 4a below the second back pressure chamber 13b. And the entire back pressure chamber is set to an intermediate pressure.

The center of the first annular groove 8a is made to coincide with the center of the orbiting scroll wrap 6b of the orbiting scroll 6. The cross-sectional shape of the first annular groove 8a is substantially U-shaped. The second annular groove 11a and the outer groove 11b are formed on the bottom surface of the bearing 11. Also,
The second annular groove 11a and the outer groove 11b may be formed on the back surface of the orbiting end plate 6a of the orbiting scroll 6.

With the above structure, the entire back pressure chamber on the back of the orbiting scroll 6 is set at the intermediate pressure, the thrust receiving surface 11c on the bearing 11 side is widened, and the thrust force for pressing the orbiting scroll 6 against the bearing 11 is made uniform. Thus, the scroll compressor which suppresses the dancing phenomenon of the orbiting scroll 6 and performs a well-balanced orbiting motion to improve performance and efficiency can be achieved.

FIGS. 5 and 6 show another embodiment of the present invention, in which a first back pressure chamber 13 is provided between the center of the rear surface of the orbiting end plate 6a of the orbiting scroll 6 and the bottom surface of the crankshaft 8.
a, and a second back pressure chamber 13b is formed between the outer peripheral portion of the back surface of the turning head plate 6a and the bearing 11, and a second back pressure chamber 13b is formed between the back intermediate portion of the turning head plate 6a and the bearing 11. Two annular grooves 11
a ', an outwardly extending outer groove 11b', and an inwardly extending inner groove 11c 'are formed. The Oldham ring 7 is fitted into the second annular groove 11a', and the first back pressure chamber 13a and the second It is configured to communicate with the back room 13b.

The other embodiments are similar to the first embodiment.
The entire back pressure chamber on the back of the orbiting scroll 6 is set to an intermediate pressure, the thrust receiving surface on the bearing 11 side is widened, the thrust force for pressing the orbiting scroll 6 against the bearing 11 is made uniform, the dancing phenomenon of the orbiting scroll 6 is suppressed, and balance is achieved. A scroll compressor that can perform good orbiting motion and improve performance and efficiency.

[0024]

As described above, in the present invention, the entire back pressure chamber on the back side of the orbiting scroll is set to the intermediate pressure, the thrust receiving surface on the bearing side is widened, and the thrust force for pressing the orbiting scroll against the bearing is made uniform. A scroll compressor that suppresses the dancing phenomenon of the orbiting scroll and achieves a well-balanced orbiting motion to improve performance and efficiency.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a scroll compressor showing one embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part showing an embodiment of the present invention.

FIG. 3 is an enlarged sectional view of a main part showing a tip seal fitting portion of the embodiment of FIG. 2;

FIG. 4 is an enlarged sectional view of a main part of the bearing of the embodiment of FIG. 2 as viewed from below.

FIG. 5 is a longitudinal sectional view of a scroll compressor showing another embodiment of the present invention.

FIG. 6 is an enlarged sectional view of a main part showing another embodiment of the present invention.

FIG. 7 is a longitudinal sectional view of a scroll compressor showing an outline of a conventional example.

FIG. 8 is an enlarged sectional view of a main part of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealed container 2 Electric motor 3 Compression part 4 Fixed scroll 4a Fixed end plate 4b Fixed scroll wrap 5 Compression chamber 6 Orbiting scroll 6a Orbiting end plate 6b Orbiting scroll wrap 6c Orbital drive shaft 6d Pressure contact surface 7 Oldham ring 8 Crankshaft 8a First annular groove 9 Lubrication oil passage 9a Throttle mechanism 10 Shaft 11 Bearing 11a Second annular groove 11b, 11b 'Outer groove 11c Thrust receiving surface 11c' Inner groove 12 Chip seal 13a First back pressure chamber 13b Second back pressure chamber

Claims (7)

[Claims] An electric motor and a compression section are arranged vertically in a sealed container, and the compression section is combined with the fixed scroll having a spiral wrap on a head plate to form a plurality of compression chambers. A orbiting scroll to be formed, a shaft that supports a orbiting drive shaft of the orbiting scroll, forms a crankshaft at the lower end, drives the orbital drive, and forms a lubricating oil passage that penetrates from the upper end to the lower end; A scroll compressor comprising: a throttling mechanism provided on an outlet side of the lubricating oil supply path; and a first annular groove provided on a bottom surface of the crankshaft in a press-contact surface between the bearing and the crankshaft. , Insert the tip seal into the first annular groove,
A first back pressure chamber is formed between the center of the back surface of the orbiting scroll head and the bottom surface of the crankshaft, and a second back pressure chamber is formed between the outer peripheral portion of the back surface of the head of the orbiting scroll and the bearing. A second annular groove and an outer groove facing outward are formed on the outer periphery of the first back pressure chamber between the back surface of the end plate of the orbiting scroll and the bearing, and the first back pressure chamber and the second back pressure are formed. A scroll compressor characterized by communicating with a chamber. 2. The scroll compressor according to claim 1, wherein a center of said first annular groove is made coincident with a center of a rotation axis of said orbiting scroll. 3. The scroll compressor according to claim 2, wherein the first annular groove has a substantially U-shaped cross section. 4. The scroll compressor according to claim 1, wherein the second annular groove and the outer groove are formed on a bottom surface of the bearing. 5. The scroll compressor according to claim 1, wherein the second annular groove and the outer groove are formed on a back surface of the orbiting scroll head plate. 6. An electric motor and a compression unit are disposed vertically in a sealed container, and the compression unit is provided with a fixed scroll having a spiral wrap on a head plate, and a plurality of compression chambers meshed with the fixed scroll. The orbiting scroll to be formed, an Oldham ring for preventing the orbiting scroll from rotating, and a lubricating oil supply passage that supports the orbiting drive shaft of the orbiting scroll and forms a crankshaft at the lower end to orbitally drive and penetrates from the upper end to the lower end. And a bearing configured to support the crankshaft, wherein a first back pressure chamber is formed between a central rear surface of the orbiting scroll head and the bottom surface of the crankshaft. Forming a second back pressure chamber between the outer peripheral portion of the back surface of the end plate of the orbiting scroll and the bearing, and forming a second back pressure chamber between the intermediate portion of the back surface of the end plate of the orbiting scroll and the bearing. An outer groove towards Jo groove and the outer,
An inner groove extending inward, the Oldham ring being fitted into the second annular groove, and a communication between the first back pressure chamber and the second pressure back chamber. . 7. The bearing according to claim 6, wherein the second annular groove, the outer groove and the inner groove are formed on the bottom surface of the bearing.
The scroll compressor as described.