JP3483909B2 - Scroll compressor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic scroll compressor, and more particularly, to an oil supply device for a bearing portion of a compressor. 2. Description of the Related Art As disclosed in Japanese Patent Application Laid-Open No. 5-1680, a conventional lubricating structure of a hermetic scroll compressor is provided with a lubricating device having a drive shaft having a spherical slide at both ends on a motor end surface side. A universal joint having a bearing is formed, and an oil passage communicating between an oil supply hole provided in the drive shaft and a separate oil reservoir via the joint is formed. [0003] A separate oil reservoir and the discharge gas in the compressor have been communicated by piping. The oil stored in the oil separator was guided to the sealed container by piping, and then to a spherical slide bearing provided in the lower part of the sealed container in the axial direction of the drive shaft. This spherical plain bearing was connected to a pedestal. On the other hand, another spherical plain bearing was provided on the end face of the drive shaft, the central part of the two spherical plain bearings was press-fitted to one side, and the other was connected by a pipe having a gap movable in the axial direction. . In this manner, the oil supply hole provided in the drive shaft and the oil reservoir are in communication with each other through the joint having the spherical slide bearings at both ends. [0004] In the above-mentioned prior art, the oil under high pressure of the oil separator is compressed by utilizing the differential pressure through an oil supply passage formed by a spherical plain bearing joint. It is led to each sliding part inside the machine. Spherical plain bearings provided in the inserted drive shaft direction pedestals in the bottom sealed container is being accumulated oil to the action of high pressure to the lower end, whereas the upper end is in a high-pressure gas in the closed container. Since the pressures are equal to each other, lubrication using the differential pressure cannot be performed, so that there is a problem that wear occurs at the upper end of the spherical plain bearing. Further, the spherical plain bearing joint is connected so that the upper end surface of the pedestal and the upper surface of the bearing are substantially at the same position in order to absorb a mounting error in a direction perpendicular to the axial direction of the drive shaft. An object of the present invention is to provide a scroll compressor capable of stably supplying oil to a spherical plain bearing without impairing a function of absorbing a mounting error in a direction perpendicular to the axial direction of a drive shaft. [0007] In order to achieve the above object, the present invention relates to a method of connecting a compression mechanism, a discharge connection portion of a sealed container containing an electric motor and an oil separator by a discharge pipe, In a scroll compressor that forms an oil passage that connects an oil supply hole provided near a motor-side end face of a separator and a drive shaft of a compression mechanism through a spherical slide bearing joint, a housing height of a base into which a spherical slide bearing joint is inserted. The height is made higher than the bearing portion of the bearing joint to provide an oil reservoir, and the inner diameter of the upper portion of the pedestal housing is set to be larger than the inner diameter of the joint portion of the bearing joint with the bearing. The oil stored in the oil separator is supplied to each sliding portion of the compressor by a differential pressure through a spherical slide bearing joint. The oil supplied to each bearing is discharged into the closed container together with the discharge gas. A portion of the discharged oil continues on the drive shaft and reaches a pedestal to which the spherical bearing joint is coupled. Since the upper end surface of the pedestal is higher than the spherical plain bearing, oil can be stored on the upper surface of the spherical plain bearing. This oil enables the spherical plain bearing to obtain sufficient lubrication for lubrication of the upper part of the bearing. Furthermore, the inner diameter of the upper end of the pedestal is set to be larger than the inner diameter of the joint of the spherical bearing, so that even if the spherical sliding bearing joint piping is inclined due to mounting error in the direction perpendicular to the axial direction of the drive shaft, it will be at the upper end of the pedestal. No contact. With this configuration, stable lubrication to the spherical plain bearing can be achieved without impairing the function of absorbing a mounting error in the direction perpendicular to the drive shaft direction. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the overall structure of a hermetic scroll compressor embodying the present invention. In FIG. 1, a scroll compression mechanism 2, an electric motor 3 for driving the scroll compression mechanism 2, and the like are housed in a closed container 1, and a lower portion is a space 4.
The scroll compression mechanism 2 includes a orbiting scroll 5, a fixed scroll 6, a drive shaft 7 serving as a slank driven by an electric motor 3, a frame 8, and a rotation preventing mechanism 9. The orbiting scroll 5 has a spiral wrap 5b on a base plate (end plate) 5a. A bearing 5c into which the crankpin portion 7a of the drive shaft 7 is inserted is provided on the back surface of the base plate 5a.
Is provided on the base plate 5a, and a pressure equalizing hole 5d for communicating the space of the wrap 5b in the middle of compression with the back pressure chamber 8c is provided. Fixed scroll 6 fixed to frame 8
Also has a spiral wrap 6b on the base plate 6a. A suction hole 6c is provided at the outer periphery of the wrap, and a discharge hole 6d is provided at the center of the wrap. A frame 8 fixed to the container 1 has bearings 8a, 8a 'for supporting the drive shaft 7, a pedestal 8b for clamping the orbiting scroll 5 with the fixed scroll 6, and an appropriate pressing force to the orbiting scroll 5. There is provided a back pressure chamber 8c for giving. The orbiting scroll 5 and the fixed scroll 6 are combined with the wraps 5b and 6b facing inward, and the orbiting scroll 5 is held between the fixed scroll 6 and the base 8b of the frame 8. A rotation preventing mechanism 9 for preventing rotation of the orbiting scroll is provided between the back surface of the orbiting scroll and the frame. One end of the drive shaft 7 is a bearing 5
c has a crankpin 7a supported thereon. In the drive shaft 7, an oil supply hole 7c is provided on the center of rotation of the drive shaft 7. One end of the oil supply hole 7c is open to the end face of the crank pin 7a, and the other end penetrates to the end face of the electric motor 3, and supplies oil to the bearings 8a and 8a 'via the oil supply hole 7f. A spherical plain bearing 10 is provided on the motor-side end face of the drive shaft 7. On the other hand, an oil supply pipe 1
5 is connected to the oil separator 11, and the oil supply pipe 15 is in communication with an extension of the drive shaft 7 in the axial direction. Spherical plain bearings 10 and 12 are provided on a base 16 at the end face of the oil supply pipe 15. Further, the two spherical plain bearings 10, 12
The oil supply piping joint 13 which communicates with the oil supply pipe is provided. Next, the operation of the scroll compressor will be described. When the drive shaft 7 is rotated by the electric motor 3, the orbiting scroll 5 makes a revolving motion without rotating due to the rotational motion of the crank pin 7a and the action of the automatic prevention mechanism 9. As a result, the orbiting scroll 5 and the fixed scroll 6
The space formed by the wraps 5b, 6b and the base plates 5a, 6a decreases in volume while moving to the center, compresses the gas sucked from the suction hole 6c, and discharges the gas from the discharge hole 6d. The discharged gas cools the electric motor 3 through the base plate 6a of the fixed scroll 6 and the passage 12 formed in the frame 8, and is then discharged from the discharge pipe 1c. When the scroll performs a compressing action, a force for separating the orbiting scroll 5 and the fixed scroll 6 acts. To prevent this, the pressure in the back pressure chamber 8c on the back of the orbiting scroll is increased by the pressure equalizing hole 5d. Is maintained at a pressure lower than the discharge pressure and higher than the suction pressure (intermediate pressure). As a result, the end faces of the orbiting scroll bearing 5c and the frame bearing 8a 'on the back pressure chamber 8c side are maintained at an intermediate pressure. On the other hand, the discharge pipe 1c provided at the lower part of the closed vessel 1 is connected to the oil separator 11 and the discharge pipe 14. The inside of the oil separator 11 has a structure in which the discharged refrigerant and the oil are separated, the oil is stored in a lower portion, and the refrigerant is guided from an upper portion to a refrigeration cycle. Lower part of separator 11 and spherical plain bearing 12
Are connected to each other through a pedestal 16 by an oil supply pipe 15, the oil separator 11 is in a discharge pressure state, and the oil is supplied from the oil separator 11 through the oil supply pipe 15 to the spherical plain bearings 10, 12 at both ends. It is led to an oil supply hole 7c of the drive shaft 7 through an oil supply pipe joint 13 having the same. The inside of the oil supply hole 7c is filled with the oil of the discharge pressure, and the end surface of the bearing 8a 'of the orbiting scroll 5 and the frame 8 on the back pressure chamber 8c side is at an intermediate pressure, so that each bearing has a differential pressure between the discharge pressure and the intermediate pressure. Is supplied to the sliding surface. The spherical plain bearing 12 is connected to a base 16. The upper end surface of the pedestal 16 is located at a position higher than the upper end of the spherical plain bearing 12. Oil is retained in the oil reservoir 16 a and supplied from above the spherical plain bearing 12. Since the inner diameter of the upper end of the pedestal 16 is set to be larger than the inner diameter of the spherical bearing coupling portion,
Even when the spherical slide bearing joint pipe 13 is tilted due to a mounting error in a direction perpendicular to the drive shaft direction, the upper end of the pedestal 16 is not contacted. According to the present invention, the height of the housing of the pedestal into which the spherical plain bearing joint is inserted is made higher than that of the bearing of the spherical plain bearing joint, and the inner diameter of the upper part of the housing of the pedestal is set at the joint of the spherical plain bearing joint with the bearing. By setting the inner diameter to be larger than the inner diameter, stable oil supply to the spherical plain bearing can be performed without impairing the function of absorbing a mounting error in a direction perpendicular to the drive shaft direction.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a hermetic scroll compressor showing one embodiment of the present invention. FIG. 2 is an oil supply system diagram of the compressor shown in FIG. [Description of Signs] 1 ... closed container, 1c ... discharge pipe, 2 ... scroll compression mechanism, 3 ... electric motor, 4 ... orbiting scroll, 6 ... fixed scroll, 7 ... drive shaft, 7c, 7f ... oil supply hole, 8 ... frame Reference numeral 10: spherical plain bearing, 11: oil reservoir, 12: spherical plain bearing, 13: oil supply pipe joint, 14: discharge pipe, 1
5 ... oil supply piping, 16 ... pedestal, 16a ... oil reservoir.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kazuo Sakurai 390 Muramatsu, Shimizu-shi, Shizuoka Pref. Hitachi, Ltd. Shimizu Plant (56) References JP-A-5-1680 (JP, A) JP-A-5-10264 (JP, A) JP-A-62-113879 (JP, A) JP-A-3-217678 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04C 18/02 311 F04C 29 / 00 F04C 29/02 311

Claims (1)

(57) [Claim 1] A base plate and a spiral formed integrally with the base plate
Fixed scroll and orbiting scroll consisting of round wrap
When the rotation preventing mechanism for the orbiting without rotation of the orbiting scroll relative to the fixed scroll, a drive shaft for turning drive the orbiting scroll, the drive shaft
A supporting frame, an electric motor driving the drive shaft,
In an airtight container, a discharge connection part of the airtight container and an oil separator are connected by a discharge pipe, and the oil separator and an oil supply hole provided in the vicinity of the motor-side end face of the drive shaft are spherically slipped. axis
Spherical plain bearing joint with bearing, oil supply pipe joint and pedestal
In the vertical scroll compressor, the spherical plain bearing joint is provided at an end of the drive shaft.
Spherical sliding bearing and spherical sliding provided on the pedestal
The lubrication system that connects the bearing and these two spherical plain bearings
A spherical plain bearing provided in the pedestal, comprising: a pipe joint;
Is inserted and set in the pedestal,
An oil reservoir is formed in the pedestal above the bearing,
The inner diameter is the same as that of the spherical plain bearing installed on this pedestal.
Be larger than the inner diameter of the pedestal at the joint
A closed scroll compressor characterized by the following.