JPS62218678A - Scroll compressor - Google Patents

Abstract

PURPOSE:To improve the sealing ability for a sliding portion by forming oil retaining means on the sliding portion between a turning scroll baseplate and a fixed scroll outer wall and feeding oil from a back pressure chamber. CONSTITUTION:Oil retaining means 4e is provided on the upper surface of the outer peripheral portion of a back pressure hole 4a communicating the back of a turning scroll 4 and a portion in a lap 4b and a baseplate 4a. There is provided a passage 6e for connecting a notch 6a where the baseplate 4a of the turning scroll 4 is enclosed and a back pressure chamber 6b. Oil of the oil retaining means 4e seals a sliding portion between the outer peripheral portion of the turning scroll baseplate and the outer wall of a fixed scroll 5. Accordingly, differential pressure in oil feed pressure between an intake chamber and the sliding portion can be lessened to reduce leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a scroll compressor, and particularly to a seal structure for a sliding portion of an orbiting scroll base plate.

[Conventional technology]

Regarding the oil supply structure for the sliding part of the orbiting scroll base plate of a scroll compressor, there is Japanese Patent Application Laid-Open No. 56-165787, which describes a structure in which oil is supplied together with the bearing using discharge pressure. Furthermore, a structure in which oil is supplied at a discharge pressure from the fixed scroll side is disclosed in JP-A-58-140494, and a structure in which oil is supplied at an intermediate pressure is disclosed in JP-A-59-87291. JP 59-1108
83, etc. Furthermore, the pressure increasing effect on the outer peripheral portion of the orbiting scroll base plate is described in Japanese Patent Laid-Open No. 59-119091. However, no consideration was given to the sealing performance of the outer periphery of the orbiting scroll base plate.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not give consideration to the sealing performance of the sliding portion of the outer peripheral portion of the orbiting scroll base plate.

When the operating speed changes, such as when driving with an inverter, there is a problem that performance deteriorates, especially during low-speed operation.

Furthermore, no consideration was given to the relationship between oil supply and the thrust load of the scroll, resulting in a problem in which the pressure in the back pressure chamber was high, resulting in insufficient oil supply to the bearings during low pressure ratio operation.

An object of the present invention is to improve the sealing performance of the contact sliding portion between the outer periphery of the base plate of the orbiting scroll and the outer wall of the fixed scroll.

[Means for solving problems]

The above object is to form an oil retaining means in the contact sliding part between the outer peripheral part of the orbiting scroll base plate and the fixed scroll outer wall, and to supply pressurized oil generated in the space of the outer peripheral storage part of the orbiting scroll base plate to the oil retaining means. It is achieved by doing.

[For production]

The orbiting scroll base plate is pressed toward the fixed scroll by the force of the intermediate gas pressure in the back pressure chamber while rotating. The back pressure chamber temporarily stores oil that has been used to supply and lubricate the crankshaft, etc.

It is completely full. The core part is returned to the compression chamber through the oil return hole provided in the plywood of the orbiting scroll, but some of the oil is returned to the outer periphery of the orbiting scroll base plate and the frame notch which is the outer periphery storage area of the orbiting scroll base plate. The oil enters the space between the oil and the inner wall, and the space is also filled with oil. The gap between the outer periphery of the orbiting scroll base plate and the inner wall of the frame notch, which forms the space, is constantly changing according to the orbiting movement of the orbiting scroll, and when the gap approaches the minimum gap, the oil is also pressed and a pressure increase effect occurs. to generate pressurized oil. The pressurized oil is supplied through a passage provided in the orbiting scroll base plate or the fixed scroll outer wall to an oil retaining means such as a ring groove opened in the sliding surface between the orbiting scroll base plate outer periphery and the fixed scroll outer wall. . Since a ring-shaped oil film is thereby formed, the sliding surface can be reliably lubricated and sealed.

〔Example〕

The present invention will be explained below with reference to an embodiment shown in FIGS. 1 to 16. FIG. 1 shows the structure of a compressor embodying the present invention. In a hermetic compressor that has a compression mechanism 1 above and a motor 2 below and is housed in a closed container 3, the compression mechanism includes an orbiting scroll 4, a fixed scroll 5, a frame 6,
A six-swivel scroll consisting of a crankshaft 7° rotation prevention mechanism 8 has a thinly wound wrap 4b on a base plate 4a, and a swing bearing 4C on the back side of one plywood. Also, there is a back pressure hole 4d that communicates between the back surface of the orbiting scroll and the inner part of the wrap, an oil retaining means 4e on the upper surface of the outer peripheral part of the base plate, and a cutout in the frame 6 that houses the oil retaining mechanism and the base plate of the orbiting scroll 4. It has a passage 4f communicating with the notch and a communication passage opening 4g.

The fixed scroll 5 has a wrap 5b on a base plate 5a, and the outside of the wrap is an outside Q5c. Suction hole 5 on the outer wall
d, and has a discharge hole 5e in the center of the wrap. The frame 6 has a notch 6a in which the base plate of the orbiting scroll 4 is housed.
, a back pressure chamber 6b formed on the back surface of the base plate of the orbiting scroll 4, a bearing 6c for supporting the crankshaft 7, and a pedestal 6d for supporting the motor. It also has a passage 6e that communicates the notch 6a and the back pressure chamber 6b. The crankshaft 7 has a crank 7a at one end, an oil absorption pipe 7b at the other end, and a balance weight 7c is attached. Also, there is an oil supply hole 7d inside the shaft.
has.

The orbiting scroll 4 and the fixed scroll 5 are assembled with their laps facing inward, and the fixed scroll 5 is fixed to the frame 6, thereby sandwiching the outer peripheral portion of the orbiting scroll base plate with a minute gap.

Further, the outer part of the base plate of the orbiting scroll 4 and the outer wall of the fixed scroll 5 form a sliding part to separate the back pressure chamber 6b on the back surface of the orbiting scroll from the inner periphery of the outer wall of the fixed scroll (suction chamber). . A rotation prevention mechanism 8 is installed on the back surface of the orbiting scroll 4. The crankshaft 7 is supported by the frame 6, and the rotor 2a of the motor 2 is installed below. The stator 2b of the motor 2 is fixed to the pedestal 6d of the frame 6. The compression mechanism 1 is press-fitted into a closed container 3, and separates the inside of the container into an upper discharge chamber 3a and a lower motor chamber 3b. Both are communicated through a passage 9 provided on the outer periphery of the compression mechanism 1. Further, a guide 1o is provided inside the container at the outlet of the passage 9.

The guide 10 has an opening 10a near the coil end 2c of the motor 2. Further, the lower part of the container becomes an oil sump 3c. When the crankshaft 7 rotates due to the rotation of the motor 2, the orbiting scroll 4 performs an orbiting motion due to the action of the rotation prevention mechanism 8, and the orbiting scroll 4 and the fixed scroll 5
The volume of the space formed by the wrap and plywood decreases as it moves toward the center, so the suction gas sucked in from the outside is compressed and discharged from the discharge boat 5e. The back pressure chamber 6b formed on the back surface of the orbiting scroll 4 is connected to the back pressure hole 4.
d, the pressure becomes intermediate, higher than the suction pressure and lower than the discharge pressure, and the orbiting scroll 4 is pressed against the fixed scroll 5.

The oil in the oil reservoir 3c below the closed container 3 is supplied to sliding parts such as bearings through the oil suction pipe 7b and the oil supply hole 7d due to the differential pressure between the discharge pressure and the pressure in the back pressure chamber. Oil discharged from a sliding part such as a bearing passes through a back pressure chamber 6b, is discharged into the compression chamber from a back pressure hole 4d, and is discharged together with gas from a discharge hole 5e. The discharged oil and gas flow through passage 9. Closed container 3 by guide lO
It flows along the motor chamber 3b and collides with the coil end 2c of the motor 2 through the opening 10a. The oil separated at the coil end 2c of the motor 2 flows into the oil reservoir 3c below, and the gas flows along the inner wall of the container and is discharged from the discharge pipe 11.

A portion of the oil in the back pressure chamber 6b is sent to the notch portion of the frame 6 through the passage 6e due to expansion of the balance weight 7c, movement of the anti-rotation mechanism 8, and the like. The oil in the notch is pressurized near the portion where the gap between the base plate and the frame notch becomes smaller due to the rotating movement of the plywood of the orbiting scroll 4.

The pressurized oil is supplied to the oil holding means 4e through the opening 4g and the passage 4f. The oil in the oil retaining means 4e lubricates and seals the sliding parts of the orbiting scroll base plate outer periphery and the fixed scroll outer wall. Although not shown, a plurality of passages 4f and 6e are provided on the orbiting scroll base plate. opening 4g
serves to communicate the pressure increasing portion in the frame cutout and the passage 4f for a longer time, and prevents excessive pressure increase. Similarly, the passage 6e also prevents excessive pressure rise. That is, Figure 2~
As shown in FIG. 5, the gap between the outer periphery of the orbiting scroll 4 and the notch of the frame 6 changes with the orbiting movement of the orbiting scroll 4, and becomes minimum at the point where the orbiting scroll 4 is closest. Therefore, the oil is compressed and the pressure increases in this minimum gap. The opening 4g of the ring groove-shaped recess provided on the outer circumferential side of the base plate of the orbiting scroll 4 widens the range of this minimum gap, thereby preventing excessive pressure rise. Moreover, since the passage 6e provided in the frame 6 also communicates the minimum gap and the back pressure chamber 6b, excessive pressure rise is prevented. In the present invention, the pressure of the oil supplied to the sliding portion is not the oil at the discharge pressure but the oil at an intermediate pressure, so that the force that separates the scrolls becomes smaller.

That is, the thrust force is reduced by that amount, so that pressing by the intermediate pressure applied to the back pressure chamber can be performed with a small force. The distance between the oil retaining ring groove 4e and the outer periphery of the orbiting scroll base plate, and the distance between the ring groove 4e and the inner periphery of the outer wall 5c of the fixed scroll 5 as shown in FIG.
The turning radius should be smaller than the turning radius. As a result, sufficient oil can be supplied to the sliding range of the orbiting scroll base plate. This result is shown in the fixed scroll 5 as in the embodiment shown in FIG.
This is further promoted by providing a ring groove 4e' also in the outer wall portion 5C. That is, sufficient oil can be supplied from the base plate on the side where the orbiting scroll 4 approaches the frame notch. Also, the sealing effect is doubled. As for the shape of these grooves, in addition to the above-mentioned ring grooves, a ring-shaped interrupted groove 14e as shown in the embodiment shown in FIG. 7 can also be used.

In consideration of oil supply and sealing properties, it is desirable that the distance between the interrupted grooves be 2 times the turning radius or less. Moreover, it is good also as a plurality of circular arc grooves. Further, by providing the communication passage 4f in the groove 14e in the rotation direction of the orbiting scroll 4 at the rear end, the oil pressure supplied to the base plate of the orbiting scroll 4 can be controlled. That is, the orbiting scroll 4 is in the frame 6.
The orbiting scroll 4 It is possible to reduce the force that acts on the orbiting scroll and tends to tilt the orbiting scroll. When the passage communicating the oil retaining means and the frame notch is provided in the above-mentioned orbiting scroll base plate, it is of course possible to provide a plurality of structures such as the embodiment shown in FIG. 8. Also, Figures 9 to 10
It may be provided on the outer wall of the fixed scroll 5 as in the embodiment shown in the figure. In this case, it is effective to provide grooves 24e also in the outer wall portion 5c of the fixed scroll, as shown in FIG.

In FIG. 9, when the fixed scroll is not provided with the groove 24e, the oil supply to the ring groove 4e on the orbiting scroll base plate becomes intermittent. The communication passages 14f and 24f provided in the outer wall portion 5c of the fixed scroll 5 can be obtained by making one or both of them oblique as in the embodiment shown in FIG. In all of these embodiments, the communication passage is provided in the orbiting scroll base plate or the fixed scroll outer wall 5c, but as in the embodiments shown in FIGS. 11 to 13, the communication passage is provided in the orbiting scroll base plate. Or groove 3 provided in the sliding part of the outer wall of the fixed scroll.
4f also has a similar function. In addition, also in these structures, a plurality of passages 34f openings 6e can be provided. The opening 6e may be a ring-shaped groove provided on the outer circumferential surface of the base plate of the orbiting scroll 4 as in the embodiments shown in FIGS. 2 and 3, and in this case, the opening 6e has a larger area than the communication passage 4f.

Also in the embodiment shown in FIG. 8, the area of the opening 4g is set larger than the communication path 4f. As in the embodiment shown in FIG. 14, openings 4g may be partially provided on the outer circumferential side of the orbiting scroll base plate. In this case, if the communication passage 4g is provided at the tip of the opening 4g with respect to the rotating direction of the orbiting scroll, it can be effectively used for the pressure increasing part of the frame cutout from the initial stage of pressure increase, and the base plate of the orbiting scroll can also be provided in the frame cutout. Refueling can be done forward to the point of approach to the section. This structure can also be applied to the case where communicating passages 24g and 44f are provided on the outer wall of the fixed scroll as in the embodiments shown in FIGS. 15 and 16. Although not shown, the present invention can also be applied to a structure in which a communicating path is provided in the sliding portion of the outer wall of the fixed scroll.

〔Effect of the invention〕

According to the present invention, the oil in the back pressure chamber can be supplied to the sliding part between the orbiting scroll base plate and the fixed scroll outer wall, so the differential pressure between the supply oil pressure in the suction chamber and the sliding part is reduced, and leakage is reduced. . In addition, since the pressure of the oil supplied to the sliding parts is lower than the conventional oil pressure equal to the discharge pressure, the force that tries to separate the orbiting scroll is reduced, and the back pressure for branching the orbiting scroll can be reduced. can. Therefore, the differential pressure between the discharge pressure and the back pressure chamber is increased, and the oil supply capacity is improved.

[Brief explanation of drawings]

Fig. 1 is an overall sectional view of the scroll compressor of the present invention;
The figure is the first partial sectional view, the third figure is a plan view of the second figure, and the fourth figure is a partial cross-sectional view of the first figure.
1, FIG. 5 is a plan view of FIG. 4, and FIG. 6 is a partial sectional view of FIG. 1. 7 is a partial plan view of FIG. 1, FIG. 8 is a partial plan view of FIG. 1, FIG. 9 is a partial sectional view of FIG. 1, FIG. 10 is a partial sectional view of FIG. The figure is a partial sectional view of Figure 1, and Figure 12.
The figure is a plan view of FIG. 11, FIG. 13 is a partial sectional view of FIG. 1, FIG. 14 is a partial plan view of FIG. 1, FIG. 15 is a partial sectional view of FIG. FIG. 15 is a plan view of FIG. 15; DESCRIPTION OF SYMBOLS 1... Compression mechanism, 2... Motor, 2a... Rotor, 2b... Stator, 3... Airtight container, 3a...
・Discharge chamber, 3b...Motor chamber, 3c...Oil reservoir, 4
...Orbiting scroll, 4a...Bed plate, 4b...Wrap, 4c...Orbiting bearing, 4d...Back pressure hole, 4e
...Ring groove for oil retention, 4f...Communication path, 4g.
...Opening, 5...Fixed scroll, 5a...Bed plate, 5b...Wrap, 5c...Outer wall, 5d...
Suction hole, 5e...Discharge hole, 6...Frame, 6a.
...Notch, 6b...Back pressure chamber, 6c...Bearing, 6
d... Pillar, 6e... Passage, 7... Crankshaft,
7a...Crank, 7b...Oil absorption pipe, 7c...
Balance weight, 7d... Oil supply hole, 8... Rotation prevention mechanism, 9... Passage, 10... Guide, 10a...
- Opening, 11...discharge pipe. Agent Patent Attorney Tadashi Akimoto Figure 1 Figure 2 Figure 4e Figure 5 Figure 6 Figure 6e Figure 7 Figure 8 Figure 9 Figure 70 Figure 1/Figure 12 Figure 78 Figure 14

Claims (6)

[Claims] 1. An orbiting scroll having a spiral-shaped wrap standing upright on a base plate is combined with a fixed scroll wrap, and the outer circumference of the orbiting scroll base plate and the outer wall of the fixed scroll are brought into contact and slid, and the back surface of the orbiting scroll is Scroll compression has a structure in which a back pressure chamber is formed in the back pressure chamber, the back pressure chamber is maintained at an intermediate pressure between high and low pressure to support the thrust load, and the bearing part is lubricated by the pressure difference between the discharge pressure and the back pressure chamber. In the machine, an oil retaining means is formed and provided in a sliding part formed by the outer peripheral part of the base plate of the orbiting scroll and the outer wall of the fixed scroll, and the oil retaining means is formed on the sliding part formed by the outer peripheral part of the base plate of the orbiting scroll and the outer wall of the base plate of the orbiting scroll. A scroll compressor characterized in that a passage is provided that communicates a space between the plate outer periphery and the oil retaining means, and the space is provided in communication with the back pressure chamber. 2. 2. The scroll compressor according to claim 1, wherein the oil retaining means is a ring-shaped groove provided in a sliding portion of the outer peripheral portion of the orbiting scroll base plate. 3. The oil retaining means is a double ring-shaped groove, one of which is provided on the sliding surface of the outer periphery of the orbiting scroll base plate, and the other one is provided on the sliding surface of the outer wall of the fixed scroll. Scroll compressor according to scope 1. 4. The scroll compressor according to claim 1, wherein the distance from the position of the oil retaining means to the outer peripheral end of the orbiting scroll base plate or the distance to the inner end of the fixed scroll outer wall is smaller than the orbiting radius of the orbiting scroll. 5. A passage that communicates the oil retaining means with the space between the inner wall surface of the orbiting scroll base plate storage portion and the outer periphery of the orbiting scroll base plate is provided in the orbiting scroll base plate or the fixed scroll outer wall. Scroll compressor according to scope 1. 6. A passage communicating between the inner wall surface of the orbiting scroll base plate storage portion and the outer periphery of the orbiting scroll base plate and the oil retaining means is connected to a recess provided on the outer periphery of the orbiting scroll base plate and the oil retaining means from the recess. 2. The scroll compressor according to claim 1, comprising a narrow hole communicating with the scroll compressor.