JPH0472485A - Scroll compressor - Google Patents

Abstract

PURPOSE:To impede the contraflow of refrigerant simply and with space saving structure by disposing a float valve for closing a suction port at the stop time of a scroll compression element, at a suction hole. CONSTITUTION:An axial suction hole 29 is formed at the driven shaft 22 of a driven scroll 15, and an end plate 41 with a suction port 40 formed therein is fixed to the opening end part 39 of the suction hole 29. In this case, a float valve 42 is disposed in the suction hole 29. The float valve 42 is thereby spaced from the end plate 41 by the suction pressure gas refrigerant at the action time of a scroll compression element 3 so as to open the suction port 40, and brought into close contact with the end plate 41 by the contraflow pressure of the gas refrigerant at the stop time so as to close the suction port 40. The contraflow of the refrigerant can be thereby impeded simply with space saving structure.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention provides a drive shaft or a driven shaft of a scroll compression element.
The present invention relates to a scroll compressor having an axial suction hole.

(B) Prior Art In the conventional scroll compressor described in Japanese Patent Publication No. 1-34312, which precedes the present invention, a check valve is provided in the suction passage hole of the scroll compression element. and its biasing spring is located in the compression chamber, so
The disadvantage is that the effective compression volume of the compression chamber is narrowed, and the backflow refrigerant pressure acts from a side direction with respect to the operating direction of the check valve, causing the check valve to tilt and making it impossible to reliably close the valve port. The biasing spring is indispensable, and there are drawbacks such as an increase in the number of parts.

(c) Problems to be Solved by the Invention The present invention solves the above-mentioned drawbacks and provides a scroll compressor that has a simple and space-saving configuration and can prevent backflow of refrigerant.

(D) Means for Solving the Problems In the present invention, the scroll compression element is composed of a driving scroll and a driven scroll that engages with and follows the driving scroll, and the driving shaft and the driven shaft of both scrolls are connected to each other. By eccentrically supporting the main frame and the auxiliary frame and rotating them using electric elements, the volume of the compressed space between the scrolls is gradually reduced from the outside to the inside of the scrolls. The refrigerant is made by compressing a gaseous refrigerant, and an axial suction hole is formed in the drive shaft or the driven shaft, and an end plate with a suction port is fixed to the open end of the suction hole. At the same time, when the scroll compression element is in operation, it is separated from the end plate by the suction pressure of the gaseous refrigerant to open the suction port, and when the scroll compression element is stopped, the suction port is opened in close contact with the end plate by the backflow pressure of the gaseous refrigerant. A float valve that closes is arranged in the suction hole.

(E) Function According to the present invention, when the scroll compression element is stopped, even if a backflow of refrigerant occurs from the compression space to the suction side low pressure space, the float valve is operated by the backflow pressure and the suction port is closed. Therefore, noise generation due to reverse rotation of the scroll compressor, damage to the meshing portion between both scrolls, backflow of lubricating oil, etc. can be prevented.

In addition, since the scroll compression element effectively utilizes the existing axial suction hole of the drive shaft or driven shaft and arranges the float valve, there is no need for a dedicated storage space for the float valve, etc., and this scroll compression element can be used. It can be made compact and have a simple backflow prevention mechanism.

(f) Example Next, one embodiment of the present invention will be described.

In FIGS. 1 and 2, (1) is a closed container in which an electric element (2) is housed on the lower side and a scroll compression element (3) is housed on the upper side. Electric element (2)
is composed of a stator (4) and a rotor (5) disposed inside the stator.

There is an air gap (
6) is formed. A passage (7) is formed by cutting out a portion of the outer periphery of the stator (4). (8)
A main frame is mounted in pressure contact with the inner wall of the closed container (1), and a main bearing (9) is provided in the center of this frame. (10) is also an auxiliary frame attached to the inner wall of the closed container (1) in pressure contact, and this auxiliary frame has a center 02 with a distance ε from the center O1 of the main bearing (9) of the main frame (8). An auxiliary bearing part (11) is provided. The main frame (8) and the auxiliary frame (lO) are fixed with bolts (I3) so as to form a space (12) inside.

The scroll compression element (3) is composed of a driving scroll (14) driven by the electric element (2) and a driven scroll (15) that rotates in the same direction as the driving scroll. The drive scroll (14) has a cylindrical end plate (16), a spiral wrap (17) made of an involute curved line erected on one side of the end plate, and a spiral wrap (17) on the other side of the end plate (16). The central protruding rotor (
5) Drive inserted and fixed in *! (181). The driven scroll (15) has a cylindrical end plate (19
), and an annular wall (20) that protrudes from the periphery of one side of the end plate and slides into contact with the end plate (16) of the drive scroll (14).
, a spiral wrap (21) consisting of a curve of an involute angle correction tooth profile surrounded by this annular wall and erected on the head plate (19), and a driven shaft protruding from the center of the other surface of the head plate (19). (22).

The coordinates of the involute wrap (17) are X=R(c
osθ+θsinθ) Y=R(sinθ−θcosθ), and the lap coordinates of the involute angle correction tooth profile are X=-R
[cos# + (θ+β)sill(θ1β)]Y=
−R(giI!θ−(θ+β)cot(θ+β)]β
= jan-' (sin θ/(pcoso ten ε
)] However, R: radius of the base circle, P: radius of the circular orbit of the driving pin. The driving scroll (14) is connected to the main frame (
The drive shaft (18) is pivotally supported by the main bearing (9) of the auxiliary frame (lO), and the driven scroll (15) is pivotally supported by the driven shaft (22) by the auxiliary bearing (11) of the auxiliary frame (lO).
14) (15) wrap (171F211) space (12
) so as to face each other and engage with each other to form a plurality of compressed spaces (23) inside.

The main frame (8) and the auxiliary frame (10) partition the inside of the closed container (1) into a low pressure chamber (24) and a high pressure chamber (25).

The drive shaft (18) is provided with a discharge hole (26) through which the refrigerant compressed in the compression space (23) is communicated with the high pressure chamber (25). This discharge hole has discharge ports (27) that open into the high pressure chamber (25) at the upper and lower sides of the electric element (2), respectively.
Two (28) are provided.

The driven shaft (22) is provided with an axial suction hole (29) that guides the refrigerant in the low pressure chamber (24) into the compression space (23). (30) is a communication passage provided in the head plate (19), and this passage communicates with the suction hole (29) and is connected to the compression space (2) from the outside.
3) to guide the refrigerant.

(31) is a drive device, and this drive device includes a drive pin (32) provided protruding from the outer periphery of the end plate (16) of the drive scroll (14), and an annular shape of the driven scroll (15) into which this drive pin is fitted. It consists of a guide groove (33) provided in the wall (20) in the radial direction. This guide groove is formed into a U-shape by cutting out the outside. Guide groove (33)
The outer peripheral end of the circular orbit is located outside the circular orbit at the center of the drive pin (32). 9 (34) is a small hole provided in the end plate (16) of the drive scroll (14). The compression space (23) in the middle of compression is communicated with the space (12). The space (12) and the low pressure chamber (24) are the auxiliary bearings (11) of the auxiliary frame (10).
A sealing member (
35) is sealed. Space (12) and hyperbaric chamber (25)
) means the main bearing (9) of the main frame (8) and the drive shaft (18).
) is sealed with a sealing member (36) provided on the sliding surface.

(37) is a suction pipe, and this suction pipe communicates with the inside of the low pressure chamber (24). (38) is a discharge pipe, and this discharge pipe communicates with the high pressure chamber (25).

The suction hole (29) has an end plate (40) formed at the open end (39) of the suction hole (29).
41) is fixed, and a float valve (42) is arranged inside this suction hole (29).

As shown in FIGS. 3 and 4, the end plate (41) is
The opening end (39) is pressed by the stopper ring (43) fitted on the inner periphery of the auxiliary bearing (11).
) is fixed. In addition, the float valve (42
) is formed in a substantially cross shape and moves in sliding contact with the inner wall surface of the suction hole (29) with four protrusions (44), and at the same time, the disc portion (45) in the center is connected to the suction port (29). 40) Larger configuration. The float valve (42) is operated as shown in FIG. 4(a) when the scroll compression element (3) is operated.
As shown in , the end plate (
41), the suction port (40) is opened, and immediately after it comes into contact with the upper part (46), the end plate (41) is opened by the backflow pressure of the gaseous refrigerant as shown in FIG. The suction port (40) is closed in close contact with the suction port (40).

Next, the operation and effect of the scroll compressor will be explained.

In the scroll compressor, when the electric element (2) rotates, its rotational force is transmitted to the drive scroll (14) through the drive shaft (18). The rotational force transmitted to the drive scroll is transmitted to the driven scroll (15) via the drive device (31), causing the driven scroll to rotate in the same direction as the drive scroll (14). The driven scroll (15) rotates at a position offset from the center of the driven shaft (22) by a length ε with respect to the center of the drive shaft (18) of the drive scroll (14). Drive scroll (
14) and a driven scroll (15), the compression space (23) formed by these scrolls is gradually reduced from the outside to the inside, and the low pressure chamber (24) is opened from the suction pipe (37).
) into the suction hole (29) of the driven shaft (22).
From there, it flows into the outer compression space (23) through the communication passageway (3o) of the end plate (19) and is compressed. This compressed refrigerant is transferred to the drive shaft (18) of the drive scroll (14).
through the discharge hole (26) provided in the discharge port +27)
(28) into the high pressure chamber (25), and the discharge pipe (3
8) to the outside of the closed container (1). In addition, medium-pressure refrigerant in the compression space (23) during compression flows through small holes (34).
Discharge into the space (2) from the drive scroll (14)
and the driven scroll (15), so that the tips of the wraps (17) and (21) of these scrolls maintain a certain clearance from each other so that the end plate <161
(It is made to slide to 191.

The rotation of the driving scroll (14) causes the driven scroll (15
) is rotated in the same direction by a drive device (31) that rotates the guide groove (
By forming the circular orbit at the outer peripheral end of the drive bin (33) outside the circular orbit at the center of the drive bin (32), the drive bin (32) is prevented from coming out of the guide groove (33), and - At (32), the driven scroll (15) is rotated in the same direction as the driving scroll (14) to rotate the compressed space (
23) to enable compression. Furthermore, the centers of the driving scroll (14) and the driven scroll (15) are eccentric by a length ε, and the lap of the driving scroll (14) (
By forming the wrap (21) of the driven scroll (15) into a spiral consisting of an involute-shaped curve, the wrap (17) is formed into a spiral consisting of an involute-shaped curve.
(This prevents the contact portion 21i from separating or making abnormal contact, and allows compression to be performed in the compression space (23).

The annular wall (20) of the driven scroll (15) slides on the outer periphery of the end plate (16) of the driving scroll (14) to open the space (1).
By shielding with 2), compressed space (23) and space (
12). space (1
2) is the sealing member (35) f36) and the low pressure chamber (24)
and high pressure chamber (25), and a small hole (3
By guiding medium-pressure refrigerant during compression in step 4), the pressure can be maintained at a constant medium pressure while preventing low-pressure refrigerant or high-pressure refrigerant from entering.
4) and the driven scroll (15) can be made to have an appropriate axial sealing force. Further, excessive contact force is prevented from being applied locally to the driving scroll (14) and the driven scroll (15).

The refrigerant compressed in the compression space (23) is discharged through the discharge hole (26).
Refrigerant is discharged into the high pressure chamber (25) through the upper discharge port (27) and lower discharge port (28) of the electric element (2), respectively. At the same time, the refrigerant discharged from one discharge port (28) flows through the air gap (6) of the electric element (2).
and through the passage (7) to the discharge pipe (38), effectively cooling the electric element (2) and making the heat of this electric element available.

Further, in the scroll compressor, the scroll compression element (
3) When the refrigerant is stopped, even if a backflow of refrigerant is about to occur from the compression space (23) to the suction port side low pressure chamber (24), the float valve (42) is operated by this backflow pressure and the suction port (40) is closed. Therefore, noise is generated due to the reversal of the scroll compressor, and both scrolls (1
4) (This will prevent damage to the meshing part between 151 and backflow of lubricating oil. In addition, the scroll compression element (3) can be inserted into the existing axial suction hole (151) of its driven shaft (11).
Since the float valve (42) is arranged by effectively utilizing the float valve (42), there is no need for a dedicated storage space for the float valve (42), etc., making the scroll compression element (3) compact and with a simple backflow prevention mechanism. Can be done.

FIG. 5 shows another embodiment, in which a compression coil spring (47) that presses the float valve (42) against the end plate (41) is arranged in the suction hole (29).
The float valve (4) is opened by the suction pressure of the gaseous refrigerant.
2), the suction port (40) opens by compressing the compression coil spring (47), and when the scroll compression element stops, the compression coil spring (47) opens.
) also acts on the float valve (42), so that the float valve (42) closes smoothly and instantaneously. In this embodiment, the other parts are constructed in the same manner as in the previous embodiment, and their explanation will be omitted.

In addition, regarding the suction valve mechanism composed of the float valve (42), the end plate (41), etc., the driven shaft (22)
In place of this, a refrigerant suction hole is formed in the drive shaft (18),
A device in which the suction valve mechanism is provided in the suction hole is also implemented.

(g) Effects of the Invention Although the present invention is constructed as described above, even if the refrigerant tries to flow back from the compression space to the suction side low pressure space immediately after the scroll compression element stops, the float valve operates due to the backflow pressure and the suction side is sucked. The opening is now closed, thereby preventing noise generation due to reverse rotation of the scroll compressor, damage to the engagement portion between both scrolls, and backflow of lubricating oil.

In addition, since the scroll compression element stores the float valve by effectively utilizing the existing axial suction hole of the drive shaft or driven shaft, this scroll compression element eliminates the need for a dedicated storage space for the float valve, etc. Combat I
・The backflow prevention mechanism can be made simple.

Therefore, it is possible to provide a scroll compressor that can prevent refrigerant backflow with a simple and compact configuration.

[Brief explanation of the drawing]

1 to 4 show one embodiment of the present invention, FIG. 1 is a longitudinal sectional view, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG. 3 is a top view of the main parts. Fig. 4(a) is an explanatory diagram of the operation of the scroll compression element in the same main part during operation, Fig. 4(b)
is an explanatory diagram when the scroll compression element is stopped in the same main part. FIG. 5 is a vertical sectional view of the main part of another embodiment of the present invention. (2)...Electric element, (3)...Scroll compression element, (8)...Main frame, (10)...Auxiliary frame, (14)9. . Driving scroll, (15)...Following scroll, (1
8)... Drive shaft, (22)... Driven shaft, (23)...
...Compression space, (29)...Suction hole, (39)...Open end, (40)...Suction port, (41)...End plate,
(42)...Float valve, (47)...Spring.

Claims (2)

[Claims] (1) The scroll compression element is composed of a driving scroll and a driven scroll that engages with and follows the driving scroll, and the driving shafts and driven shafts of both scrolls are eccentric to each other, and the shafts are mounted on the main frame and the auxiliary frame, respectively. By supporting the refrigerant and rotating it by an electric element, the gaseous refrigerant is compressed by gradually reducing the volume in the compression space between the scrolls from the outside to the inside of the scrolls. An axial suction hole is formed in the drive shaft or the driven shaft, and an end plate having the suction port is fixed to the open end of the suction hole, and when the scroll compression element is operated, gas is A float valve is attached to the suction hole, and the float valve is moved away from the end plate to open the suction port by the suction pressure of the gaseous refrigerant, and when stopped, the float valve is brought into close contact with the end plate and closes the suction port by the backflow pressure of the gaseous refrigerant. A scroll compressor characterized by the following: (2) The scroll compressor according to claim 1, wherein a spring for pressing the float valve against the end plate is disposed in the suction hole.