JPH06341383A - Sealed type scroll fluid device - Google Patents

Abstract

PURPOSE:To increase the rigidity and strength of a revolving bearing detention part of a revolving scroll with the main shaft and prevent seizure and gall by forming the detention part from an eccentric shaft part in eccentricity from the axis of the main shaft and a concave boss which is installed in the revolving scroll for accommodating the eccentric shaft part. CONSTITUTION:In a sealed vessel 1, a compression element part and a motor part are accommodated while connected by a main shaft 7. The compression element part is so arranged that a stationary scroll 2 coupled with a frame 4 and a revolving scroll 3 (a, b) mesh with one another. The main shaft 7 provided in continuity to motor 11 is supported rotatably on the frame 4 by a bearing 8. The revolving bearing detention part 8a of the revolving scroll 3 with the main shaft 7 is composed of an eccentric shaft 7a in eccentricity from the axis of the main shaft 7 and a concave boss 3c which is furnished on the counter-lap side of a revolving scroll end plate for accommodating the eccentric shaft part 7a. The oil in the sealed vessel 1 is introduced to an oil pressure chamber 7c situated between the eccentric shaft part 7a and the boss 3c.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic scroll compressor used as a refrigerant compressor for refrigeration or air conditioning or a helium liquefaction compressor. A conventional structure of a hermetic scroll compressor is disclosed in Japanese Patent Laid-Open No. 53-35840. In this reference, the scroll fluid device is fixed in a closed container via a flange. Further, a structure is disclosed in which a refrigerant gas is guided to the outside of a hermetically sealed container and discharged from a discharge port at the center of a fixed scroll, which is a compression element portion of a scroll fluid device. It should be noted that the suction gas is introduced into the space inside the closed container, and the structure is in an atmosphere of suction pressure that is a low pressure including the surroundings of the electric motor. As a technical problem of the hermetic scroll compression device, in the above cited example, since the atmosphere around the drive shaft of the scroll fluid device has a low suction pressure atmosphere, the bearing part is not provided. Since the method of lubrication by the centrifugal pump action by the rotation of the spindle is adopted as the lubrication method of
There is a problem that it is difficult to always secure the amount of oil.
In addition, since the back surface of the end plate of the orbiting scroll has the same low-pressure suction pressure atmosphere, it is equipped with a thrust bearing portion that receives gas force due to the internal pressure of the scroll portion that is the compression element portion, and that portion has an excessive thrust force. You will receive it. Therefore, it is necessary to secure a sufficient oil supply amount also in the thrust bearing portion that receives the thrust force. In particular, if the pump head, which is the distance between the lower end of the main shaft and the bearing, is large, the amount of oil supply is limited in the above-described oil supply method using the centrifugal pump action. For this reason, there is a problem in that the lubrication oil is insufficient and the lubrication of each sliding portion of the compressor is poor, so that the reliability around the bearing is deteriorated and the reliability of the compressor itself is impaired. The present invention has been invented in view of the above-mentioned problems, that is, a hermetic scroll fluid device according to the first aspect of the present invention is a scroll compression device in a hermetic container. The compressor and the electric motor are connected to each other through the main shaft and stored, and the scroll compressor is such that the fixed scroll and the orbiting scroll in which the spiral wrap is upright on the disk-shaped end plate are engaged with each other with the wrap inside. The orbiting scroll is formed by an end plate and a frame of the orbiting scroll, which engages with an eccentric shaft portion which is continuously provided on a main shaft having a balance weight portion, and causes the orbiting scroll to orbit with respect to a fixed scroll without rotating. A back pressure chamber is provided, and the balance weight portion of the main shaft is disposed in the back pressure chamber, and the fixed scroll has a discharge port opening at the center and an intake port opening at the outer periphery. A port is provided, gas is sucked in through the suction port, the volume is reduced by moving around the closed space formed by both scrolls to compress the gas, and the compressed gas from the discharge port is sealed with oil at the bottom. In a sealed scroll fluid device that discharges gas into a container and further discharges gas to the outside of a container through a discharge pipe, a boss portion is provided on the back face of an orbiting scroll end plate, and an eccentric shaft portion that is continuous with the main shaft is attached to the boss portion. A slewing bearing portion is provided, and an oil pressure chamber is formed by an axial gap formed by the tip portion of the eccentric shaft portion and the bottom portion of the boss portion, and the oil at the bottom portion of the container is provided through an oil supply hole provided in the main shaft. It is characterized in that it is configured so that a part of the high-pressure oil, which is supplied to the hydraulic chamber and has a pressure substantially equal to the discharge pressure in the hydraulic chamber, flows into the back pressure chamber through the bearing gap of the slewing bearing portion. is there. Further, in the hermetic scroll fluid device according to the second aspect of the present invention, on the basis of the same premise as in the first aspect of the invention, the oil in the bottom of the container is slewing bearing through an oil supply hole provided in the main shaft. And a main bearing portion, oil leaking from the bearing portion is introduced into the back pressure chamber, and an oil supply path for guiding the oil inside the back pressure chamber from the outer peripheral portion of the orbiting scroll end plate to the suction chamber is configured. It is characterized by. [0006] As described above, a hydraulic chamber formed of an axial gap formed by the tip of the eccentric shaft and the bottom of the boss is formed on the rear surface of the end plate of the orbiting scroll, with the inside of the sealed container as an atmosphere of discharge pressure. By further providing the slewing bearing portion, the oil at the bottom of the closed container is supplied to the hydraulic chamber through the oil supply hole provided in the main shaft, and the oil in the hydraulic chamber is provided through the bearing gap of the slewing bearing portion. A part of the high pressure oil can be made to flow into the back pressure chamber. That is, the minute bearing gap of the orbiting bearing portion functions as a throttle for the oil supply system, and each bearing portion (sliding portion) can always be lubricated by the differential pressure oil supply method. Further, since the leaked oil from the bearings of the main bearing portion and the orbiting bearing portion is flowing into the back pressure chamber which is the space behind the end plate, the balance weight portion in the oil can splash the oil, The oil that has flowed in from the bearing portion sufficiently spreads to the key groove portion around the Oldham ring and contributes to the lubrication of that portion, and the lubricity around the Oldham ring is improved. Further, since the oil supply path is constituted by the differential pressure for guiding the oil in the back pressure chamber from the outer peripheral portion of the orbiting scroll end plate to the suction chamber in the outer peripheral portion of the wrap, there is an effect that the lubrication of the outer peripheral surface portion of the orbiting scroll end plate can be improved.
As described above, according to the present invention, a special oil supply pump is unnecessary, and the cost is reduced. Also, due to the structure of the hydraulic chamber at the tip of the eccentric shaft (high-pressure oil region at a pressure approximately equal to the discharge pressure), the force due to this hydraulic pressure can be used as the supporting force for supporting the orbiting scroll, and the behavior of the orbiting scroll is stable. It has the effect of promoting Further, oil can be accumulated in the tip end portion of the eccentric shaft portion due to viscosity or the like, delay of oil supply to the slewing bearing portion at the time of starting can be prevented, and reliability of the bearing portion can be improved. An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. 1 and 2 show an embodiment of the present invention. The closed container 1 is divided into two parts 1a and 1b, and these two parts are later joined to form an integral airtight container. The fixed scroll 2 includes an end plate 2a,
It consists of a wrap 2b standing upright on this end plate 2a. Further, the fixed scroll is provided with a suction port 2c on its outer peripheral portion and a discharge port 2d on the central portion of the end plate 2a. The discharge port 2d opens in the closed container chamber 1 and maintains the closed container 1 at a discharge pressure. The orbiting scroll 3 includes a wrap 3b standing upright on a disk-shaped end plate 3a, and a scroll boss 3c formed on the surface (back surface) on the side opposite to the wrap. Each of the wraps 2b and 3b of the scrolls 2 and 3 is formed into an involute curve or a curve similar thereto. The fixed scroll 2 and the orbiting scroll 3 are meshed with each other with the wraps 2b and 3b facing each other. The frame 4 has a space for accommodating the orbiting scroll 3 and an automatic blocking member 5 which will be described later, and is connected to the outer peripheral portion of the fixed scroll 2 by several bolts (not shown). The outer peripheral surface is closely fitted and joined to the inner wall of the closed container 1. The outer peripheral surface of the fixed scroll 2 is closely fitted and joined to the inner wall of the closed container 1. The rear surface of the end plate 3a of the orbiting scroll 3 is supported by the frame 4, and the end plate 3a can move without being so far from the end plate 2a of the fixed scroll 2. The rotation preventing member 5 comprises a ring having grooves (not shown) on one surface and the other surface and an Oldham key fitted in each groove,
The above grooves are orthogonal to each other. One groove has a frame
The Oldham Key-6 fixed to M4 is fitted.
The main shaft (crankshaft) 7 is supported by a bearing 8 attached to the frame 4. An eccentric shaft portion (crank pin) 7a is provided on the head portion of the crankshaft 7 at a position separated from the axial center of the crankshaft 7 by a distance corresponding to a turning radius ε, and a balance weight portion 7b.
The crank pin 7a is fitted and engaged with the orbiting scroll boss 3c. A space (axial gap) extending in the axial direction is formed above the upper end surface of the crank pin 7a in the engaging portion between the two. The oil supply hole 9 is formed in the crankshaft 6 from its lower end surface to its head portion, and opens at the upper end surface of the crankpin portion. The orbiting scroll 3 is provided with a boss portion 3c on the rear surface of the end plate, and the boss portion 3c is provided with an orbiting bearing portion 8a that engages with an eccentric shaft portion 7a that is continuous with the main shaft 7. The tip end portion of the eccentric shaft portion 7a and the boss portion 3c are provided. An oil pressure chamber 7c formed by an axial gap formed with the bottom is provided, and oil at the bottom of the closed container is supplied to the oil pressure chamber 7c through an oil supply hole 9 provided in the main shaft 7, and from the slewing bearing portion 8a. A part of the high pressure oil having a pressure substantially equal to the discharge pressure in the hydraulic chamber 7c is caused to flow into the back pressure chamber 25 through the bearing gap. The oil at the bottom of the container is supplied to the orbiting bearing portion 8a and the main bearing portion 8b through the oil supply holes 9 provided in the main shaft 7, and the oil leaking from these bearing portions 8 flows into the back pressure chamber 25. I am busy. Further, the oil supply path is configured by the differential pressure between the pressure (intermediate pressure) of the back pressure chamber and the suction pressure so that the oil inside the back pressure chamber 25 is guided to the suction chamber through the outer peripheral portion of the orbiting scroll 3. . Incidentally, reference numeral 11 is an electric motor,
The stator is closely attached to the inner wall of the closed container 1. Reference numeral 12 is a suction pipe connected to the suction pipe 2c of the fixed scroll 2, and reference numeral 13 is a discharge pipe. In the closed container, a space is divided by the frame 4 into a discharge chamber 20 on the side opposite to the wrap side of the fixed scroll 2 and a motor chamber 22 on the side of the electric motor 11, and a flow path connecting the discharge chamber 20 and the electric motor chamber 22. 21 (21a, 21b, 21c, 21
d, 21e) is provided along the inner wall of the closed container 1a at the outer edge of the frame. A discharge pipe 13 that discharges gas from the electric motor chamber 22 side is provided. The discharge pipe 13 is located above the electric motor chamber 22 in the vicinity of the outer edge of the frame 4,
It is installed on the wall portion of the closed container 1a that does not axially overlap with the communication channel 21. Next, the oil supply passage 10 is provided with an orbiting scroll 3
And is provided in the orbiting scroll 3, and extends radially from the central portion of the orbiting scroll 3. The center portion of the oil supply passage 10 and the oil supply hole 9 communicate with each other in a space (hydraulic chamber) 7c formed in an engaging portion of the scroll boss 3c and the crankshaft 7. Further, the oil discharge end of the oil supply passage 10 is opened to the sliding surface between the fixed scroll 2 and the orbiting scroll 3. FIG. 3 shows another embodiment of the oil supply passage 10, in which the oil discharge end of the oil supply passage 10 is opened to the end surface of the wrap 3b. Others are the same as FIG. 1 and FIG. FIG. 4 shows still another embodiment of the oil supply passage 10, in which the oil discharge end of the oil supply passage 10 is closed space V.
1 is opened. Others are the same as those in FIGS. 1 and 2. The oil stored in the bottom portion of the closed container 1 receives the discharge pressure, rises in the oil supply hole 9 and flows into the space (axial gap) of the engaging portion, enters the oil supply passage 10 from this, and then the fixed scroll 2 And the sliding surface of the orbiting scroll 3, the sliding surface of the wrap 3b and the end plate 2a of the fixed scroll 2, or the sealed space V1. The refrigerant gas is introduced into the compression element portion in the closed container through the suction pipe 12, is compressed there, and the lubricating oil supplied to the sliding portion, the bearing and the like is supplied to the back pressure chamber and thus the orbiting scroll. 3 from the outer peripheral portion of the end plate to the suction chamber, through the oil supply path by the pressure difference between the intermediate pressure and the suction pressure, and guided to the compression element portions 2 and 3 to be mixed. The refrigerant gas mixed with the lubricating oil becomes a high temperature and a high pressure and is discharged from the discharge port 2d, so that the discharge chamber 20 and the communication passage 21 are electrically connected to the electric motor chamber 22.
Will be moved to. Here, the oil in the refrigerant gas is separated and collected at the bottom of the closed container. Although the discharge pressure was used when oil was supplied to each sliding surface and the closed space V1, the lower end of the oil supply hole 9 was opened at the axial center, and the head was located at a position away from the axial center. If you open it,
The pores 9 themselves can have a pumping action, and this pumping action and discharge pressure can be used together. According to each of the embodiments of the oil supply passage 10 described above, the oil supply hole that is in constant communication with the crankshaft and the orbiting scroll is provided, so that it is possible to perform forced oil supply to the sliding surface between the orbiting scroll and the fixed scroll and the sealed space. Refueling is reliable. Therefore, it is possible to improve the lubrication of each sliding surface to significantly reduce frictional damage and prevent seizure. Further, the high-pressure oil having a pressure substantially equal to the discharge pressure acting on the space (axial gap) formed in the crankshaft head can give an axial pressing force to the orbiting scroll, and the gas pressure in the compression chamber The separating force can be made smaller, and the orbiting motion of the orbiting scroll can be stabilized. According to the present invention, the following effects can be obtained. (1) The small bearing gap of the slewing bearing portion acts as a throttle for the oil supply system, and by means of the differential pressure oil supply method, oil can be supplied to each sliding portion without fail, and the reliability of the compressor can be greatly improved. (2) No special oil supply pump is required, and the cost is reduced. (3) The balance weight portion provides an oil splashing action, and the oil flowing from the bearing portion is distributed to the key groove portion around the Oldham ring and the lubrication of that portion is improved. (4) The small bearing gap of the slewing bearing portion functions as a throttle for the oil supply system, and the differential pressure oil supply method allows the hydraulic chamber at the tip of the eccentric shaft portion to hold high-pressure oil at a pressure substantially equal to the discharge pressure. Therefore, this hydraulic force can be used as a supporting force for supporting the orbiting scroll. (5) Oil can be accumulated in the hydraulic chamber at the tip of the eccentric shaft portion due to viscosity or the like, delay of oil supply to the swivel bearing portion at the time of start can be prevented, and the reliability of the bearing portion can be improved. You can

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a view showing another embodiment of the oil supply passage provided on the end plate of the orbiting scroll. FIG. 4 is a view showing still another embodiment of the oil supply passage. [Explanation of Codes] 1 ... Airtight container 2 ... Fixed scroll 3 ... Orbiting scroll 4 ... Frame 7 ... Crankshaft 7c ... Hydraulic chamber 8a ... Orbiting bearing portion 8b ... Main bearing portion 9 ... Oil supply hole 10 ... Oil supply passage 25 ... Back pressure chamber

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[Procedure amendment] [Date of submission] March 23, 1994 [Procedure Amendment 1] [Amendment target document name] Specification [Amendment target item name] Full text [Amendment method] Change [Amendment content] [Document name] Specification BOOK Title of the Invention Closed scroll fluid device [Claims] [1] A scroll compression element part and an electric motor are connected and housed in a closed container via a main shaft, and the compression element part is a disk. A fixed scroll and an orbiting scroll in which a spiral wrap is upright on a plate-shaped end plate are engaged with each other with the wrap being inside, and the frame in which the fixed scroll is connected to it and the rotation of the orbiting scroll are blocked to prevent rotation. It consists of a member and a main shaft that is rotatably supported by a frame via bearings and is connected to an electric motor.The fixed scroll is provided with a discharge port that opens to the center and a suction port that opens to the outer periphery. In a closed scroll fluid device that sucks gas from a mouth and moves a closed space formed by both scrolls to a central portion to reduce the volume and compress the gas, the orbiting bearing engaging portion between the orbiting scroll and the main shaft, An eccentric shaft that is eccentric from the axis of the main shaft, and a concave boss portion that is provided on the side opposite to the wrap of the orbiting scroll end plate for housing the eccentric shaft. And a bottom surface of the concave boss portion, and a means for guiding the oil in the oil reservoir in the closed container to the space is provided. [2] A means for guiding the oil in the oil reservoir in the closed container to the space between the end of the eccentric shaft and the bottom surface of the concave boss is
A means for applying a discharge gas pressure to the oil surface of the oil sump, and an oil supply hole provided in the main shaft with the lower end opened below the oil surface of the oil sump and the upper end opened at the end of the eccentric shaft. The hermetically sealed scroll fluid device according to claim 1, wherein Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic scroll compressor used as a refrigerant compressor for refrigeration and air conditioning. A conventional structure of a hermetic scroll compressor is disclosed in Japanese Patent Laid-Open No. 53-35840. In this reference, the scroll fluid device is fixed in a closed container via a flange. Further, a structure is disclosed in which a refrigerant gas is guided to the outside of a hermetically sealed container and discharged from a discharge port at the center of a fixed scroll, which is a compression element portion of a scroll fluid device. It should be noted that the suction gas is introduced into the space inside the closed container, and the structure is in an atmosphere of suction pressure that is a low pressure including the surroundings of the electric motor. In the conventional scroll fluid machine disclosed in the above cited reference, a short pin portion is formed in the central portion of the surface of the disk-shaped end plate of the orbiting scroll opposite to the wrap side. The boss portion, which is eccentric with respect to the axis of the main shaft and has a concave center portion, engages with the orbiting bearing, and the orbiting scroll is driven. Generally, steel or the like having high rigidity and strength is used for the main shaft for driving the orbiting scroll. However, since the orbiting scroll is demanded for workability and weight reduction, casting,
Materials such as aluminum alloys are used. Therefore, repetitive bending stress is applied to the pin portion on the orbiting scroll side with the orbiting motion of the orbiting scroll, and problems such as damage to the pin portion due to fatigue fracture due to the strength of the material used. Occurred. In addition, due consideration has not been given to the lubrication and lubrication of the swivel bearing engaging portion, which causes a transient lubrication delay at the time of start-up, which causes seizure and galling of the engaging portion. However, there arises a problem that the reliability of the compressor is impaired. The present invention has been invented in view of the above problems, and an object of the present invention is to increase the rigidity and strength of a slewing bearing engaging portion which engages with an eccentric portion of a main shaft, and to further enhance the engagement. It is an object of the present invention to provide a sealed scroll fluid device which is excellent in reliability by improving lubrication and lubricity of a sliding surface of the portion to suppress seizure and galling. In order to achieve the above object, the present invention accommodates a scroll compression element portion and a motor connected in series in a hermetically sealed container via a main shaft, and at the same time, the compression element portion. Is a disc-shaped end plate with a spiral wrap standing upright and engaged with the orbiting scroll with the wrap inside, and to prevent the rotation of the orbiting scroll from rotating with the frame in which the fixed scroll is connected. Of the rotation prevention member and a main shaft rotatably supported by a frame via a bearing and connected to the electric motor.The fixed scroll is provided with a discharge port opening to the center and a suction port opening to the outer periphery. In a sealed scroll fluid device that sucks gas from the suction port and moves the sealed space formed by both scrolls to the center to reduce the volume and compress the gas,
The orbiting bearing engaging portion between the orbiting scroll and the main shaft comprises an eccentric shaft eccentric from the axis of the main shaft, and a concave boss portion provided on the side opposite to the wrap of the orbiting scroll end plate for housing the eccentric shaft. In the swivel bearing engaging portion, a space is formed between the end of the eccentric shaft and the bottom surface of the concave boss portion, and means for guiding the oil in the oil reservoir in the closed container is provided in the space. It is a feature. As described above, the orbiting bearing engaging portion between the orbiting scroll and the main shaft has an eccentric shaft eccentric from the axis of the main shaft and a concave shape for accommodating the eccentric shaft on the opposite lap side of the orbiting scroll end plate. Since it is composed of the boss portion, the center diameter is increased as compared with the conventional eccentric pin type on the orbiting scroll side, so that the strength of the engaging portion is increased. On the other hand, since the main shaft is made of a material such as steel having high rigidity and high strength, the main shaft can also obtain sufficient strength, and damage such as cutting damage of the engaging portion can be prevented. Further, in the swivel bearing engaging portion, a space is formed between the end of the eccentric shaft and the bottom surface of the concave boss portion, and the space is provided with means for guiding the oil in the oil reservoir in the closed container. Forms an oil sump, which reduces the delay in oil supply to the slewing bearing even under transient conditions such as startup. Further, even if the refrigerant gas dissolved in the lubricating oil separates from the lubricating oil sent to the space, the gas accumulates in the upper part of the space and the lubricating oil accumulates in the lower part, so Since the lubricating oil containing no gas is sent, it is possible to suppress the occurrence of seizure or galling due to oil shortage in the slewing bearing. An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. 1 and 2 show an embodiment of the present invention. The closed container 1 is divided into two parts 1a and 1b, and these two parts are later joined to form an integral airtight container. The fixed scroll 2 includes an end plate 2a,
It consists of a wrap 2b standing upright on this end plate 2a. Further, the fixed scroll is provided with a suction port 2c on its outer peripheral portion and a discharge port 2d on the central portion of the end plate 2a. The discharge port 2d opens in the closed container chamber 1 and maintains the closed container 1 at a discharge pressure. The orbiting scroll 3 includes a wrap 3b standing upright on a disk-shaped end plate 3a, and a scroll boss 3c formed on the surface (back surface) on the side opposite to the wrap. Each of the wraps 2b and 3b of the scrolls 2 and 3 is formed into an involute curve or a curve similar thereto. The fixed scroll 2 and the orbiting scroll 3 are meshed with each other with the wraps 2b and 3b facing each other. The frame 4 has a space for accommodating the orbiting scroll 3 and an automatic blocking member 5 which will be described later, and is connected to the outer peripheral portion of the fixed scroll 2 by several bolts (not shown). The outer peripheral surface is closely fitted and joined to the inner wall of the closed container 1. The outer peripheral surface of the fixed scroll 2 is closely fitted and joined to the inner wall of the closed container 1. The rear surface of the end plate 3a of the orbiting scroll 3 is supported by the frame 4, and the end plate 3a can move without being so far from the end plate 2a of the fixed scroll 2. The rotation preventing member 5 comprises a ring having grooves (not shown) on one surface and the other surface and an Oldham key fitted in each groove,
The above grooves are orthogonal to each other. One groove has a frame
The Oldham Key-6 fixed to M4 is fitted.
The main shaft (crankshaft) 7 is supported by a bearing 8 attached to the frame 4. An eccentric shaft portion (crank pin) 7a is provided on the head portion of the crankshaft 7 at a position separated from the axial center of the crankshaft 7 by a distance corresponding to a turning radius ε, and a balance weight portion 7b.
The crank pin 7a is fitted into the boss portion 3c of the orbiting scroll and engaged with the orbiting bearing. A space (axial gap) extending in the axial direction is formed above the upper end surface of the crank pin 7a in the swing bearing engaging portion of both of them. The oil supply hole 9 is formed in the crankshaft 6 from its lower end surface to its head portion, and opens at the upper end surface of the crankpin portion. A boss portion 3c is provided on the rear surface of the end plate of the orbiting scroll 3, and an orbiting bearing engaging portion 8a that engages with an eccentric shaft portion 7a continuous with the main shaft 7 is provided on the boss portion 3c.
The hydraulic chamber 7c is formed by a space (axial gap) formed by the tip of a and the bottom surface of the boss 3c, and the oil in the bottom of the closed container is supplied through the oil supply hole 9 provided in the main shaft 7 to the hydraulic chamber. 7c
And a part of the high-pressure oil having a pressure substantially equal to the discharge pressure in the hydraulic chamber 7c is caused to flow into the back pressure chamber 25 through the bearing gap of the orbiting bearing engaging portion 8a. Further, the oil at the bottom of the container is supplied to the slewing bearing engaging portion 8a through the oil supply hole 9 provided in the main shaft 7 and the hydraulic chamber 7c, and the oil leaked from the slewing bearing engaging portion 8 is back pressured. Room 25
Is flowing into. Further, the oil supply path is configured by the differential pressure between the pressure (intermediate pressure) of the back pressure chamber and the suction pressure so that the oil inside the back pressure chamber 25 is guided to the suction chamber through the outer peripheral portion of the orbiting scroll 3. . Reference numeral 11 is an electric motor, and its stator is closely attached to the inner wall of the hermetically sealed container 1. Reference numeral 12 is a suction pipe connected to the suction pipe 2c of the fixed scroll 2, and reference numeral 13 is a discharge pipe. In the closed container, a space is divided by the frame 4 into a discharge chamber 20 on the side opposite to the wrap side of the fixed scroll 2 and a motor chamber 22 on the side of the electric motor 11, and a flow path connecting the discharge chamber 20 and the electric motor chamber 22. 21 (21a, 21b, 21
c, 21d, 21e) are provided along the inner wall of the closed container 1a at the outer edge of the frame. A discharge pipe 13 that discharges gas from the electric motor chamber 22 side is provided. The discharge pipe 13
Is installed on the wall of the hermetically sealed container 1a which is located above the electric motor chamber 22 and near the outer edge of the frame 4 and which does not axially overlap the communication passage 21. Next, the oil supply passage 10 is provided with an orbiting scroll 3
And is provided in the orbiting scroll 3, and extends radially from the central portion of the orbiting scroll 3. The center of the oil supply passage 10 and the oil supply hole 9 communicate with each other in a space (hydraulic chamber) 7c formed in the orbiting bearing engaging portion of the crankshaft 7 and the scroll boss 3c. Further, the oil discharge end of the oil supply passage 10 is opened to the sliding surface between the fixed scroll 2 and the orbiting scroll 3. Further, a part of the balance weight 7b provided on the upper part of the main shaft surrounds the outside of the boss so as to surround the boss and is configured to rotate, and further surrounds each of the members outside. A ring-shaped rotation preventing member is arranged. FIG. 3 shows another embodiment of the oil supply passage 10, in which the oil discharge end of the oil supply passage 10 is opened to the end face of the wrap 3b. Others are the same as FIG. 1 and FIG. FIG. 4 shows still another embodiment of the oil supply passage 10, in which the oil discharge end of the oil supply passage 10 is closed in a closed space V.
1 is opened. Others are the same as those in FIGS. 1 and 2. The oil stored in the bottom of the closed container 1 receives the discharge pressure, rises in the oil supply hole 9 and flows into the space (axial gap) of the slewing bearing engagement portion, enters the oil supply passage 10 from there, and is fixed. It is fed by pressure to the sliding surface between the scroll 2 and the orbiting scroll 3, the sliding surface between the wrap 3b and the end plate 2a of the fixed scroll 2, or the closed space V1. The refrigerant gas is introduced into the compression element portion in the closed container through the suction pipe 12, is compressed therein, and the lubricating oil supplied to the sliding portion and the bearing is supplied to the back pressure chamber and thus the orbiting scroll. 3 from the outer peripheral portion of the end plate to the suction chamber, through the oil supply path by the pressure difference between the intermediate pressure and the suction pressure, and guided to the compression element portions 2 and 3 to be mixed. The refrigerant gas mixed with the lubricating oil becomes a high temperature and a high pressure and is discharged from the discharge port 2d, so that the discharge chamber 20 and the communication passage 21 are electrically connected to the electric motor chamber 22.
Will be moved to. Here, the oil in the refrigerant gas is separated and collected at the bottom of the closed container. Although the discharge pressure was used when oil was supplied to each sliding surface and the closed space V1, the lower end of the oil supply hole 9 was opened at the axis and the head was placed at a position away from the axis. If you open it,
The pores 9 themselves can have a pumping action, and this pumping action and discharge pressure can be used together. According to each of the embodiments of the oil supply passage 10 described above, the oil supply hole that is in constant communication with the crankshaft and the orbiting scroll is provided, so that forced oiling can be performed on the sliding surface between the orbiting scroll and the fixed scroll and the sealed space. Refueling is reliable. Therefore, it is possible to improve the lubrication of each sliding surface to significantly reduce frictional damage and prevent seizure. In addition, the high-pressure oil having a pressure substantially equal to the discharge pressure acting on the space (axial gap) formed in the head of the orbiting bearing engaging portion can apply an axial pressing force to the orbiting scroll, which results in the compression chamber. The separation force due to the gas pressure can be further reduced, and the orbiting motion of the orbiting scroll can be stabilized. According to the present invention, the orbiting bearing engaging portion between the orbiting scroll and the main shaft accommodates the eccentric shaft on the lap side of the eccentric shaft eccentric from the shaft center of the main shaft and the orbiting scroll end plate. As compared with the conventional eccentric pin system on the orbiting scroll side, the center diameter increases, so that the strength of the engaging portion increases. On the other hand, since the main shaft is made of a material such as steel having high rigidity and excellent strength, the main shaft can also obtain sufficient strength, and there is an effect of preventing damage such as cutting damage of the engaging portion. Further, in the present invention, a space is formed between the end of the eccentric shaft and the bottom surface of the concave boss in the slewing bearing engaging portion, and the oil in the oil reservoir in the closed container is introduced into the space. Since the space is provided with an oil reservoir, the delay of oil supply to the slewing bearing is alleviated even under transient conditions such as starting. Further, even if the refrigerant gas dissolved in the lubricating oil separates from the lubricating oil sent to the space, the gas accumulates in the upper part of the space and the lubricating oil accumulates in the lower part, so that gas is not collected in the orbiting bearing. Since lubricating oil containing no oil is sent, it has the effect of suppressing the occurrence of seizure and galling due to oil shortage in the slewing bearing. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a view showing another embodiment of the oil supply passage provided on the end plate of the orbiting scroll. FIG. 4 is a view showing still another embodiment of the oil supply passage. [Explanation of Codes] 1 ... Airtight container 2 ... Fixed scroll 3 ... Orbiting scroll 4 ... Frame 7 ... Crankshaft 7c ... Hydraulic chamber 8 ... Bearing 8a ... Orbiting bearing 9 ... Oil supply hole 10 ... Oil supply passage 25 ... Back pressure chamber

Claims (1)

[Claims] [1] A scroll compressor and an electric motor are arranged in series in a hermetically sealed container via a main shaft to be housed, and in the scroll compressor, a spiral wrap is erected on a disk-shaped end plate. The fixed scroll and the orbiting scroll are engaged with each other with the wrap inside, and one of the orbiting scrolls is engaged with the eccentric shaft part that is linked to the main shaft with the balance weight part, and the orbiting scroll orbits with respect to the fixed scroll without rotating. A back pressure chamber formed by the end plate and the frame of the orbiting scroll that is moved is provided, and the balance weight portion of the main shaft is disposed in the back pressure chamber, and the fixed scroll has a discharge port that opens to the center. And a suction port that opens to the outer periphery are provided, gas is sucked in through the suction port, the volume is reduced by moving the scroll around the enclosed space formed by both scrolls, and the gas is discharged. Discharged into the sealed container reservoir oil at the bottom of Rino compressed gas,
Further, in a hermetic scroll fluid device that discharges gas to the outside of the device via a discharge pipe, a boss portion is provided on the back face of the orbiting scroll end plate, and the boss portion is provided with an orbiting bearing portion that engages with an eccentric shaft portion continuous with the main shaft. Provided, a hydraulic chamber consisting of an axial gap formed by the tip of the eccentric shaft and the bottom of the boss is provided, and the oil at the bottom of the container is supplied to the hydraulic chamber via an oil supply hole provided in the main shaft, A sealed scroll fluid device characterized in that a part of high-pressure oil having a pressure substantially equal to a discharge pressure in the hydraulic chamber is made to flow into a back pressure chamber through a bearing gap of the orbiting bearing portion. [2] A scroll compressor and an electric motor are connected in series through a main shaft and housed in a closed container, and the scroll compressor includes a fixed scroll and an orbiting scroll in which a spiral wrap is upright on a disk-shaped end plate. The wraps are engaged with each other, and one orbiting scroll is engaged with the eccentric shaft part that is continuous with the main shaft equipped with the balance weight part, and the orbiting scroll is orbited against the fixed scroll without rotating to rotate the orbiting scroll. A back pressure chamber formed by an end plate and a frame is provided, and a balance weight portion of the main shaft is disposed in the back pressure chamber, and a fixed scroll has a discharge port opening at the center and an outer peripheral portion. A suction port is provided, and gas is sucked in through the suction port, and the volume is reduced by moving around the enclosed space formed by both scrolls to reduce the volume and compress the gas from the discharge port to the bottom. In a sealed scroll fluid device that discharges oil into a closed container with oil stored in its part, and further discharges gas outside the device via a discharge pipe, the oil at the bottom of the container is rotated through a lubrication hole provided in the main shaft. And the main bearing portion, the oil leaking from the bearing portion flows into the back pressure chamber, and the oil inside the back pressure chamber is further guided from the outer peripheral portion of the orbiting scroll end plate to the suction chamber. Characteristic sealed scroll fluid device.