JP2865376B2 - Scroll compressor - Google Patents

Description

The present invention relates to a scroll compressor that performs compression by rotating both scrolls in the same direction.

(B) Conventional technology A conventional scroll compressor is configured such that a fixed scroll is fixed to an airtight container and the orbiting scroll is orbited around the center of the fixed scroll.

However, in the conventional one, the driving shaft of the orbiting scroll has a cantilever structure, so that the one for high-speed rotation increases vibration. Further, in the case of a large-size one, the centrifugal force of the orbiting scroll becomes extremely large, and the load acting on the bearing provided on the back of the orbiting scroll increases, which may lead to a decrease in efficiency and a decrease in reliability.

On the other hand, as a scroll compressor for high-speed rotation, Japanese Patent Publication No. 1-35196 discloses a scroll compressor in which both scrolls rotate and one scroll rotates the other scroll.

(C) Problems to be solved by the invention However, this type has the following problems. That is, since the orbiting scroll is caused to swing with respect to the drive shaft, the orbiting scroll may vibrate violently during high-speed rotation, which has not always been satisfactory as a scroll compressor for high-speed rotation.
However, in this scroll compressor, since the sliding ring is provided on the outer end plate having a high rotation speed, the relative rotation speed of the seal portion is high, and there is a problem that the durability and the sealing performance of the slide ring are deteriorated. Was.

An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a scroll compressor in which both scrolls rotating in the same direction can be sealed without impairing the durability and sealing performance of a sealing member. It is.

(D) Means for Solving the Problems The present invention accommodates a closed container, an electric element accommodated in the container, and a scroll compression element driven by the electric element. A first scroll having an axis directly or indirectly connected to the electric element by erecting a spiral wrap, and an axis eccentric to the center of the axis of the first scroll, A second scroll in which a spiral wrap is erected on a head plate facing and meshing with the first scroll, a main frame having a main bearing for supporting a shaft of the first scroll, and the second scroll And an auxiliary frame having auxiliary bearings for supporting the shafts of the first and second scrolls. These frames form a space for accommodating the first and second scrolls therein, and the inside of the sealed container is a high-pressure chamber. And a low-pressure chamber, and a passage that communicates with the high-pressure chamber or the low-pressure chamber is provided on the shaft of the first scroll and the second scroll, between the shaft of the scroll and the bearing of the frame. A seal member for sealing the shaft is provided on the thrust surface of the shaft, the seal member is formed by a thrust bush that contacts the thrust surface of the shaft and the sliding surface of the bearing, and pressing means that presses the thrust bush toward the scroll. Things.

(E) Action The present invention is configured as described above, so that a seal member for sealing between the scroll shaft and the bearing of the frame is provided on the thrust surface of the shaft, and the seal member is relatively rotated at a rotational speed. This is arranged so as to straddle both surfaces of a slow shaft portion and a non-rotating bearing so as to improve the sealing performance of the sliding surface between the shaft and the bearing and to improve the durability of the seal member.

(F) Embodiment The present invention will be described below based on an embodiment shown in the drawings.

FIG. 1 is a sectional view of a scroll compressor. In FIG. 1, reference numeral 1 denotes a closed container, in which a motorized element 2 is accommodated on a lower side, and a scroll compression element 3 is accommodated on an upper side. The electric element 2 includes a stator 4 and a rotor 5 arranged inside the stator. An air gap 6 is formed between the stator 4 and the rotor 5. A passage 7 is formed in the outer periphery of the stator 4 by being partially cut out. Reference numeral 8 denotes a main frame attached to the inner wall of the sealed container 1 by pressing, and a main bearing 9 is provided at the center of the frame. Reference numeral 10 designates an auxiliary frame which is similarly attached to the inner wall of the closed casing 1 by press-contacting. The main frame 8 and the auxiliary frame 10 are fixed with bolts 13 so as to form a space 12 therein.

The scroll compression element 3 includes a first scroll 14 driven by the electric element 2 and a second scroll 15 that rotates in the same direction as the first scroll. The first scroll 14 has a cylindrical end plate 16, a spiral wrap 17 formed of an involute-shaped curve erected on one surface of the end plate, and a protruding and rotating center of the other surface of the end plate 16. And a main drive shaft 18 inserted and fixed to the child 5. Further, the first scroll 14 constitutes a driving scroll. The second scroll 15 is composed of a cylindrical end plate 19 and a spiral wrap 20 composed of a curve of an involute angle correcting tooth profile erected on one surface of the end plate.
And a driven shaft 21 protruding from the center of the other surface of the end plate 19. The second scroll 15 forms a driven scroll.

The coordinates of the involute wrap 17 are obtained by the following equation: X = R (cos θ + θ sin θ) Y = R (sin θ−θ cos θ) = −R [sin θ− (θ + β) cos (θ + β)] β = tan ⁻¹ [sin θ / (Pcos θ + ε)] where R is the radius of the base circle and P is the radius of the orbit of the drive pin.

The first scroll 14 is supported on the main drive shaft 18 by the main bearing 9 of the main frame 8, and the second scroll 15 is
The driven shaft 21 is supported by 10 auxiliary bearings 11 and both scrolls 1
A plurality of compression spaces 22 are formed inside the wraps 17 and 20 of the 4 and 15 so that they face each other in the space 12 and engage with each other.

The main frame 8 and the auxiliary frame 10 partition the inside of the sealed container 1 into a low-pressure chamber 23 and a high-pressure chamber 24.

The refrigerant compressed in the compression space 22 is supplied to the driven shaft 21 in the high-pressure chamber.
An ejection hole 25 communicating with 24 is provided.

The main frame 8 is provided with a suction hole 26 for guiding the refrigerant in the low-pressure chamber 23 to the compression space 22.

27 is a drive device, which is a first scroll 14
A plurality of drive pins 28 protrudingly provided on the outer periphery of the
And a guide groove 29 provided radially on the outer periphery of the end plate 19 of the second scroll 15 to which the drive pin is fitted. The guide groove is formed in a U-shape by cutting out the outside. The outer circumferential end of the guide groove 29 has a circular orbit located outside the circular orbit at the center of the drive pin 28.

Reference numeral 30 denotes a seal member provided on the end face of the driven shaft 21 in the auxiliary bearing 11 of the auxiliary frame 10, and this seal member is
A thrust bush 33 that comes into contact with the thrust surface 31 of the end surface and the sliding surface 32 of the auxiliary bearing 11, and an elastic member 34 formed by a spring that presses the thrust bush toward the driven shaft 21.
And a stopper 35 for fixing one end of the elastic member.

Reference numeral 36 denotes an O-ring. The O-ring is fitted into an annular concave portion 37 provided in the auxiliary bearing 11 to seal between the O-ring and the thrust bush 33.

Reference numeral 38 denotes a suction pipe, which communicates with the low-pressure chamber 23. Reference numeral 39 denotes a discharge pipe, which communicates with the high-pressure chamber 24.

In the scroll compressor configured as described above, when the electric element 2 is rotated, the rotational force is transmitted from the drive shaft 18 to the first scroll 14. The rotational force transmitted to the first scroll is transmitted to the second scroll 15 via the driving device 27, and rotates the second scroll in the same direction as the first scroll 14. Then, the second scroll 15 is moved with respect to the center of the drive shaft 18 of the first scroll 14.
Is rotated at a position where the center of the driven shaft 21 is eccentric by the interval ε. The first scroll 14 and the second scroll 15 gradually reduce the compression space 22 formed by these scrolls from the outside to the inside, and move from the suction pipe 38 to the low-pressure chamber.
The refrigerant flowing into the space 23 is supplied to the space through the suction hole 26 of the main frame 8.
The compressed air flows into the outer compression space 22 through the inside 12 and is compressed. The compressed refrigerant is discharged into the high-pressure chamber 24 through a discharge hole 25 provided in the driven shaft 21 of the second scroll 15, and discharged from the discharge pipe 39 to the outside of the closed vessel 1. Further, the high-pressure chamber 24 and the low-pressure space 12 are sealed by a seal member 30 disposed in the auxiliary bearing 11, so that the refrigerant in the high-pressure chamber 24 does not leak into the space 12.

The thrust bush 33 is a driven shaft with a relatively slow rotation speed.
Since the thrust surface 31 is pressed against the thrust surface 31 by the elastic member 34, the sealing performance on the thrust surface 31 can be improved. In addition, the thrust bush 33 is formed of a material having excellent sliding characteristics, such as carbon and ceramic, so that wear on the sliding portion can be prevented.

Further, the thrust bush 33 is sealed by fitting the O-ring 36 into the annular concave portion 37 of the auxiliary bearing 11 which does not rotate, so that the refrigerant in the high-pressure chamber 24 does not leak into the low-pressure space 12 without impairing the sealing performance. Like that. That is, by providing the seal member 30 on the end face of the driven shaft 21, the seal member of the rotating part can be formed of a material having good sliding properties, and it is not necessary to consider both the sealing properties and the sliding properties. It can be made of material.

The centers of the first scroll 14 and the second scroll 15 are eccentric by an interval ε, the wrap 17 of the first scroll 14 is swirled by an involute curve, and the involute angle of the wrap 20 of the second scroll 15 is corrected. By forming a spiral formed of tooth-shaped curves, when rotating in the same direction as each other, the contact portions of the wraps 17, 20 are prevented from separating or abnormally contacting, so that compression can be performed in the compression space 22. .

The present invention provides the thrust bush 33 of the seal member 30 over the thrust surface 31 of the end surface of the driven shaft 21 and the sliding surface 32 of the auxiliary bearing 11 so that the thrust bush has improved sliding characteristics and sealing performance. At the same time, we are satisfied.

FIG. 2 is a sectional view of a main part of a scroll compressor showing another embodiment. The same or corresponding parts as those shown in FIG. In FIG. 2, a space 40 in which a main frame 8 accommodating a driving scroll 14 and a driven scroll 15 and an auxiliary frame 10 are formed is set to an intermediate pressure by a refrigerant in a compression space 22 in the middle of compression. In order to prevent the refrigerant in the high-pressure chamber 24 from leaking and to prevent the refrigerant in the space 40 from leaking into the low-pressure chamber 23, a thrust surface 41 is formed on the main drive shaft 18 at a stepped portion. Thrust bush 42, elastic member 43, stopper on thrust surface
A seal member 45 constituted by 44 is arranged.

(G) Effects of the Invention As described above, according to the present invention, a seal member for sealing between the scroll shaft and the bearing of the frame is provided on the thrust surface of the shaft, and the seal member is provided on the thrust surface of the shaft and the bearing. And the pressing means for pressing the thrust bush toward the scroll side, the seal member can be provided at a position where the rotational speed is relatively low, and the seal member can be provided. The sealing performance can be improved while improving the durability of the device.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a scroll compressor showing one embodiment of the present invention, and FIG. 2 is a sectional view of a main part of a scroll compressor showing another embodiment. DESCRIPTION OF SYMBOLS 1 ... Closed container, 2 ... Electric element, 3 ... Scroll compression element, 8 ... Main frame, 9 ... Main bearing, 10 ... Auxiliary frame, 11 ... Auxiliary bearing, 12 ... Space, 14 ... ... first scroll, second scroll, 18 ... drive shaft, 21 ...
Driven shaft, 23… low pressure chamber, 24… high pressure chamber, 25… discharge hole,
30,45 …… Seal member, 33,42 …… Thrust bush, 3
4,43 ... elastic member.

Claims (3)

(57) [Claims] 1. A closed container, an electric element accommodated in the container, and a scroll compression element driven by the electric element are accommodated, and the scroll compression element is provided with a spiral wrap on a head plate. A first scroll having an axis directly or indirectly connected to the electric element, and an axis eccentric to the center of the axis of the first scroll, and facing the first scroll. A second scroll in which a spiral wrap is erected on an engaging end plate; a main frame having a main bearing for supporting the shaft of the first scroll; and an auxiliary bearing for supporting the shaft of the second scroll. And a space for accommodating the first and second scrolls therein is formed by these frames, and the inside of the sealed container is partitioned into a high-pressure chamber and a low-pressure chamber, and A scroll member provided with a passage communicating with a high-pressure chamber or a low-pressure chamber on the shaft of the scroll and the second scroll, wherein a seal member for sealing between a shaft of the scroll and a bearing of a frame is provided on a thrust surface of the shaft. And a thrust bush that contacts the thrust surface of the shaft and the sliding surface of the bearing, and a pressing unit that presses the thrust bush toward the scroll. 2. The scroll compressor according to claim 1, wherein said pressing means is formed of an elastic member such as a spring. 3. The scroll compressor according to claim 1, wherein the thrust bush of said seal member is formed of a material having excellent sliding characteristics, such as carbon or ceramic.