JPH03105091A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To prevent the suction heating and improve the lubricity of a bearing surface and sealing performance between swirl bodies by forming an annular groove on a thrust bearing surface or the end plate of the second scroll in contact with the thrust bearing surface, opening an oil passage from the oil region in the high pressure environment and forming onto the end plate a passage communicating to the back surface chamber and a communication hole between the back surface chamber and an intermediate compression chamber. CONSTITUTION:The oil on the bottom part of a high pressure discharge chamber 74 is supplied into an annular groove 5 and circulates on the whole periphery, and oil lubricates a thrust bearing surface 3 and smoothes the revolution operation of the second scroll 2. Further, the oil is discharged into a back surface chamber 8 from an outer peripheral edge part 20, passing through a radial direction passage 6, and supplied into an intermediate compression chamber M through a communication hole 9. Since almost all portions of the oil used in the oil supply onto the thrust bearing surface 3 is discharged onto the back surface chamber 8 side without oozing to a suction chamber 72 side, the suction heating can be suppressed, and since the compression chamber in which oil pouring is carried out is the intermediate compression chamber M positioned in the intermediate part of a swirl, oil can be supplied favorably into the sliding parts of the swirl bodies 12 and 22, and the sealing performance between compression chambers A and B can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a scroll compressor in which one scroll is thrust-supported by pressing the other scroll with a pressing force from the back surface of the scroll.

(Prior Art) Conventionally, as disclosed in Japanese Unexamined Patent Application Publication No. Sho E30-145483 and shown in FIG. The end plate (N) of the second scroll (0) is brought into contact with the end plate (N) of the second scroll (0), and the pressure from the back chamber (P) connected to the discharge pipe (T) via the valve body (V) causes the second scroll (0) to the first scroll (F
) to provide thrust support for both scrolls against the repulsion force from the compression chambers (A, B) defined between the spiral bodies (X, Y).

In addition to ensuring good sliding movement on the thrust bearing surface (S), the sliding parts of each spiral body (X, Y) are sealed with oil to maintain airtightness within the compression chambers (A, B). To do this, an annular groove (Z) is formed in the contact part of the thrust bearing surface (S),
An oil passage (R) extending from the bottom oil area of the discharge chamber (H) is opened in the annular groove (z) to supply oil to the thrust bearing surface (S), and to prevent oil from seeping out after the bearing surface (S) is oiled. The oil coming from the outermost suction chamber (L) in contact with the bearing surface (S)
) to each spiral body (X, Y).

(Problem to be Solved by the Invention) However, in the above oil supply structure, the high pressure discharge chamber (H
) The high-temperature oil supplied from the thrust bearing surface (S) passes through the lowest pressure suction chamber (L) to each compression chamber (
A. B), there is a problem in that the intake gas is heated and the volumetric efficiency is deteriorated, leading to a decrease in performance.

In addition, since it is necessary to flow the oil against the pressure gradient from the suction chamber (L) with the lowest pressure to the compression chamber (A.B) where the pressure increases sequentially, each spiral body (X, Y) There is also a risk that the amount of oil supplied to the tank will be insufficient and the sealing performance will be impaired.

It is an object of the present invention to provide a scroll compressor that can prevent suction heating, provide good lubrication to the thrust bearing surface, and improve the sealing performance between each spiral body by devising an oil supply route. It's about doing.

(Means for Solving the Problems) Therefore, in order to achieve this object, the present invention provides a mirror plate (
11) has a spiral body (12) and the end face has a thrust bearing surface (3).
) and a second scroll (1) having a protruding outer periphery W (13), and a second scroll (1) having a spiral body (22) protruding from an end plate (21) whose outer periphery is in contact with the thrust bearing surface (3). a scroll (2), a compression chamber is defined between each of the spiral bodies (12.22), and a back chamber (8) is provided on the back surface of the mirror plate (21) in the second scroll (2). , the thrust bearing surface (3) or the bearing surface (3);
An annular groove (5) is formed in the end plate (21) of the second scroll (2) in contact with the annular groove (54), and an oil passage (50) extending from the oil region in the high pressure atmosphere is opened to the annular groove (54). A radial passageway (8) communicating with the back chamber (8) is formed on the outside of the annular groove (5), while a radial passage (8) communicating with the back chamber (8) is formed in the end plate (21) of the second scroll (2). It was decided to form a communication hole (9) which communicates the intermediate compression chamber (M) which is in the process of compression.

(Function) Oil in a high pressure atmosphere is transferred from the oil passage (50) to the annular drain (5).
and lubricates the thrust bearing surface (3). The oil in this annular groove (8) passes through the radial passage (8) and is released into the back chamber (8), and the oil accumulated in this back chamber (8) passes through the communication hole (9) and is released into the intermediate compression chamber (8). It is supplied to the chamber (M).

In this way, most of the oil used to lubricate the thrust bearing surface (3) is released to the rear chamber (8) side through the radial passage (8), so suction heating can be suppressed and oil injection is prevented. The compression chamber in which the compression is performed is an intermediate compression chamber (M) located in the middle of the spiral body (12.22).
Oil can be circulated well to the sliding parts of 2), and the sealing performance of the compression chamber can also be improved.

(Example) In the example shown in Fig. 1, a first scroll (1) serving as a fixed scroll and a second scroll (2) serving as a movable scroll are disposed facing each other inside and above a sealed casing (4). At the same time, a motor (42) coupled to a drive shaft (41) is disposed below it.

The first scroll (1) has a spiral body (12) on the lower surface of the end plate (11), and an outer peripheral wall (13) having a thrust bearing surface (3) and a support surface (30) continuous thereto on the end surface. is provided in a protruding manner and is supported and fixed via a support surface (30) to a frame (45) consisting of an upper member (43) and a lower member (44). Further, the second scroll (2) has a spiral body (22) protruding from the upper surface of the end plate (21), and the upper surface of the outer peripheral portion of the end plate (21) is brought into contact with the thrust bearing surface (3). Further, the drive shaft (41) is supported by an upper bearing (48) and a lower bearing (47), and has a pin part (48) projecting from the upper end thereof and a boss projecting from the back surface of the second scroll (2). (23), and an oil pickup (49) is attached to the lower end to pump oil from the oil reservoir (40) to the oil supply passage (49a) inside the shaft.

There are two systems of compression chambers (12.22) between each spiral body (12.22).
A. B), the second scroll (2) is driven to revolve around the first scroll (1) as the drive shaft (4l) rotates, and the suction chamber (72 ) is compressed in each compression chamber (A.B), and the high-pressure fluid is once discharged from the discharge hole (73) provided in the center of the first scroll (1) to the upper discharge chamber (74). Then, the discharged fluid is released to the lower part of the motor (42) through the discharge connection pipe (75) to cool the motor, and then taken out to the outside from the discharge pipe (78) provided at the upper part of the motor (42). That's what I do.

Further, between the upper member (43) on the cross section (45) and the end plate (21) of the second scroll (2), the end plate (21)
An annular seal ring (81) is interposed that divides the back surface of the chamber into a center and an outer periphery, and a back chamber (8
). In this way, the back chamber (
The reason why 8) is limited to the outer periphery of the second scroll (2) is because
The internal pressure of the casing (1), that is, the high pressure, acts on the center, and the back pressure of the end plate (21) of the second scroll (2) is compressed so that it gradually increases from the outer periphery toward the center. This is to match the internal pressure of the chamber and the magnitude of the separation force from the compression chamber.

With the above configuration, the thrust bearing surface (3) and each spiral body (X
, Y), as shown in Figure 2,
An annular groove (5) is formed in the end plate (21) of the second scroll (2) in contact with the thrust bearing surface (3).
5) A small-diameter tube extending from the top surface of the first scroll (1), which covers the bottom oil area of the discharge chamber (74) in a high-pressure atmosphere. The oil passage (50) is opened, and the annular groove (5)
A shallow groove-shaped radial passageway (8) communicating with the rear chamber (8) via the outer circumferential edge portion (20) of the end plate (21) is formed on the outside of the head plate (21). Here, an oil passage (50) and a radial passage (8
) have small diameters and crosspiece grooves, and the passage area is made small to prevent short circuits between the high pressure discharge chamber (74) and the intermediate pressure rear chamber (8), and to maintain a predetermined pressure. This is to create a slope.

On the other hand, the end plate (21) of the second scroll (2) is provided with a back chamber (8) that extends diagonally up and down through the thickness of the end plate (21).
A small-diameter communication hole (9) is formed to communicate the intermediate compression chamber (M) during the compression process.

With the above configuration, a pressure gradient is created sequentially from the discharge chamber (74) to the back chamber (8) and to the intermediate compression chamber (M). In this way, the high pressure discharge chamber (74
) is supplied to the annular il (5) and circulates around the entire circumference, lubricating the thrust bearing surface (3) and smoothing the revolution of the second scroll (2). The oil in this annular groove (5) passes through a radial passage (8) formed outward and is released from the outer peripheral edge portion (20) to the back chamber (8).
Further, the oil accumulated in the back chamber (8) is supplied to the intermediate compression chamber (M) through the communication hole (9). In this way, most of the oil used to lubricate the thrust bearing surface (3) is contained in the suction chamber (72
) side through the radial passageway (8), suction heating can be suppressed, and the compression chamber where oil is injected is located in the suction chamber located on the outer periphery. In contrast to (72), since the intermediate compression chamber CM) is located in the middle of the spiral, oil can be circulated well to the sliding part of the spiral body (12.22), and the compression chambers (A, B) It is also possible to improve the sealing performance between the parts.

In the above embodiment, the annular groove (5) is connected to the second scroll (
2), but the first scroll (1
) may be formed on the thrust bearing surface (3) of the outer peripheral wall (13) of the end plate (21) and the thrust bearing surface (
3) may be formed in both.

(Effect of the invention) As described above, in the present invention, the thrust bearing surface (3) or the bearing surface (
An annular groove (5) is formed in the end plate (21) of the second scroll (2) that is in contact with ,
A radial passage (8) communicating with the back chamber (8) is formed on the outside of the annular groove (5), while a radial passage (8) communicating with the back chamber (8) is formed in the end plate (21) of the second scroll (2). Since the communication hole (8) is formed to communicate with the intermediate compression chamber (M) in each spiral body (12. 22) It is possible to improve the sealing performance between the parts.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of the scroll compressor of the present invention, FIG. 2 is a plan view of the same essential parts, and FIG. 3 is a sectional view of a conventional example. (1)...First scroll (2)...Second scroll (11) (21)...End plate (12) (22)...Spiral body (13)... Outer peripheral wall (3)... Thrust bearing surface (5)... Annular groove (8)... Radial passage (8)... Back chamber (9)... Communication hole CM )・・・Intermediate compression chamber

Claims (1)

[Claims] 1) A first structure in which an outer circumferential wall (13) having a spiral body (12) and a thrust bearing surface (3) formed on an end surface protrudes from an end plate (11).
The scroll (1) and the outer periphery thereof are connected to the thrust bearing surface (3).
) and a second scroll (2) having a spiral body (22) protruding from an end plate (21) that contacts the spiral bodies (12,
22) In a scroll compressor in which a compression chamber is defined between and a back chamber (8) is provided on the back surface of the end plate (21) in the second scroll (2), the thrust bearing surface (3) or the bearing The second scroll (2) in contact with the surface (3)
) is formed with an annular groove (5) in the end plate (21), and an oil passage (50) extending from the oil area in the high pressure atmosphere is formed in the annular groove (5).
) is opened, and a radial passageway (8) communicating with the back chamber (8) is formed outside the annular groove (5), while the end plate (21) of the second scroll (2) is opened. A scroll type compressor, characterized in that a communication hole (9) is formed to communicate the back chamber (8) and an intermediate compression chamber (M) in the compression process.