WO2015155802A1

WO2015155802A1 - Scroll compressor

Info

Publication number: WO2015155802A1
Application number: PCT/JP2014/002017
Authority: WO
Inventors: 政哉岡本
Original assignee: 三菱電機株式会社
Priority date: 2014-04-09
Filing date: 2014-04-09
Publication date: 2015-10-15
Also published as: EP3130805A1; JPWO2015155802A1; CN105917120A; US20160348680A1; EP3130805A4

Abstract

A high-reliability scroll compressor is provided which has a thrust structure that uses cast iron for the orbiting scroll and comprises a steel thrust plate arranged on the back surface of the orbiting scroll, and which prevents friction and damage to the orbiting scroll and thrust plate. This scroll compressor is provided with a main body container, which is a sealed container, a fixed scroll which is fixed to the top of the main body container, an orbiting scroll (102) which is made of a cast iron material and arranged below the fixed scroll, a rotating drive shaft which has an oil passage hole that communicates vertically inside of the shaft, a frame which is fixed to the inner circumferential surface of the main body container in order to slidably support the orbiting scroll (102), a thrust plate which is made of a steel plate material and is arranged between the bottom surface of the orbiting scroll (102) and a thrust support surface of the frame, an Oldham ring which is accommodated inside of the frame, and an orbiting-side Oldham ring groove (102d) which guides the Oldham ring. On the bottom surface of the orbiting scroll (102), a circumferential groove (102f) is formed which communicates with the orbiting-side Oldham groove (102d).

Description

Scroll compressor

This invention mainly relates to a scroll compressor mounted on a refrigerant circuit such as a refrigerator, an air conditioner, or a water heater.

As a conventional scroll compressor, when the material of the orbiting scroll is made of cast iron, the orbiting scroll, a bimetallic material thrust bearing that supports the orbiting scroll, and a Swedish steel thrust plate are slid, A thrust bearing is known.
Alternatively, when the thrust load is large or the sliding characteristics are not sufficient, an oil supply hole that leads from the boss part of the orbiting scroll to the thrust surface of the orbiting scroll is provided to increase the amount of oil supply. There is also known one that prevents wear and seizure between the thrust bearing (see, for example, Patent Document 1).
Also, a thrust bearing surface that supports the orbiting scroll is formed with a plurality of spiral grooved mechanisms or a plurality of tapered land bearing mechanisms to generate oil film pressure and improve the wear resistance of the thrust bearing section. Are also known (see, for example, Reference 2).

Japanese Unexamined Patent Publication No. 5-149277 (paragraphs [0011] to [0016], FIG. 1) Japanese Patent Laid-Open No. 8-319959 (paragraphs [0018] to [0039], FIGS. 1 to 3)

The conventional thrust bearing configuration is a simple one that slides a rocking scroll made of cast iron and a thrust plate made of Swedish steel, etc., and does not use a bimetallic material thrust bearing. There has been a problem that the sliding property of the orbiting scroll and the thrust plate is deteriorated and the back surface (lower surface) of the orbiting scroll is worn or seized.

The present invention has been made to solve the above-described problems, and wears and seizes the lower surface of the orbiting scroll despite the simple configuration not using an expensive bimetallic material thrust bearing. It aims at obtaining the scroll compressor which can be suppressed.

The scroll compressor according to the present invention includes a main body container that is a hermetically sealed container, a fixed scroll fixed to an upper portion in the main body container, and a lower chamber in the center of the lower surface that is disposed below the fixed scroll to form a compression chamber together with the fixed scroll An orbiting scroll made of cast iron material having a boss portion on the top and an eccentric shaft portion that is rotatably supported by the oscillating bearing of the boss portion of the orbiting scroll is formed at the upper end portion, and communicates vertically within the shaft. A rotary drive shaft having an oil passage hole, a thrust support surface that receives the orbiting scroll, a recess that is formed on the inner side in the container radial direction from the thrust support surface and that houses the boss portion of the orbiting scroll, and a lower portion of the recess A frame having a main bearing portion that rotatably supports the rotary drive shaft and fixed to the inner peripheral surface of the main body container, a lower surface of the orbiting scroll, a thrust support surface of the frame, Ring plate-shaped thrust plate made of steel plate material that is slidably supported on the lower surface of the orbiting scroll, and accommodated in the recess of the frame to rotate around the rotation drive axis of the orbiting scroll An Oldham ring to be controlled and an Oldham groove on the lower side of the orbiting scroll formed on the lower surface of the orbiting scroll to guide the Oldham ring outside the boss portion. A circumferential groove communicating with the groove is formed.

In the scroll compressor according to the present invention, a circumferential groove communicating with the rocking-side Oldham groove is formed on the lower surface of the rocking scroll, so that a sufficient amount of lubricating oil is supplied between the rocking scroll and the thrust plate. The oil film pressure due to the wedge effect can be generated. As a result, it is possible to prevent wear on the lower surface of the orbiting scroll and to suppress seizure.

It is a longitudinal cross-sectional view of the scroll compressor in Embodiment 1 of this invention. It is a figure which shows the rocking | fluctuation scroll of the said scroll compressor, Comprising: (a) is AA arrow sectional drawing in (b), (b) is a bottom view. 2A and 2B are diagrams showing a frame of the scroll compressor, wherein FIG. 1A is a plan view, and FIG. 2B is a cross-sectional view taken along line BB in FIG. It is a top view which shows the state which mounted | wore with the Oldham ring in the flame | frame of the said scroll compressor. It is a longitudinal cross-sectional view which shows the rocking | fluctuation scroll and frame of the scroll compressor in Embodiment 2 of this invention.

Embodiment 1 FIG.
In the first embodiment, wear and seizure of the thrust surface of the orbiting scroll are suppressed.
1 is a longitudinal sectional view of a scroll compressor according to Embodiment 1 of the present invention, FIG. 2 is a view showing a swing scroll of the scroll compressor, FIG. 3 is a view showing a frame of the scroll compressor, and FIG. It is a top view which shows the state which mounted | wore with the Oldham ring in the flame | frame of the said scroll compressor.
In each figure, the scroll compressor according to this embodiment sucks the refrigerant circulating in the refrigerant circuit, compresses it into a high-temperature and high-pressure state, and discharges it to the refrigerant circuit. The scroll compressor includes a main body container 100 which is a hermetic container, a fixed scroll 101 fixedly disposed at an upper portion of the main body container 100, and an orbiting scroll disposed below the fixed scroll 101 and having a boss portion 102c on a lower surface. 102, a rotary drive shaft 114 having an oil passage hole 114 a communicating vertically with the inside of the shaft, a frame 105 fixedly arranged on the inner peripheral surface of the intermediate container of the main body container 100, and the swing scroll 102 slidably. A ring plate-like thrust plate 104 to be supported and an oil pump 108 connected to the lower portion of the rotary drive shaft 114 are provided. A discharge pipe 113 for discharging refrigerant gas is connected to the upper part of the main body container 100, and a suction pipe 112 for sucking refrigerant gas is connected to the trunk of the main body container 100. The oil pump 108 pumps up the lubricating oil (refrigerating oil) 109 accumulated at the bottom of the main body container 100 and sends it to the oil passage hole 114a.

The frame 105 includes a thrust support surface 105c that supports the orbiting scroll 102, a recess 105b that is formed on the inner side in the container radial direction of the thrust support surface 105c and accommodates the boss portion 102c of the orbiting scroll 102, and It has a main bearing portion 105a that is formed in the lower portion of the recess 105b and rotatably supports the rotary drive shaft 114. An eccentric shaft portion 110 that is rotatably supported by the rocking bearing 102a of the boss portion 102c of the rocking scroll 102 is formed at the upper end portion of the rotation drive shaft 114. In addition, an Oldham ring 103 that restricts the rotation of the rotary drive shaft 114 around the axis C of the orbiting scroll 102 is housed in the recess 105 b of the frame 105. In the recess 105b of the frame 105, a frame-side Oldham groove 105d for guiding the Oldham ring 103 is formed to extend long in the radial direction (see FIGS. 3 and 4).

Between the thrust surface 102e on the lower surface of the scroll 102 and the thrust support surface 105c of the frame 105, a thrust plate 104 made of a steel plate material that slidably supports the orbiting scroll 102 is disposed. A notch 104b communicating with the frame-side Oldham groove 105d is formed in the thrust plate 104 at a position facing the frame-side Oldham groove 105d. The notch 104b is formed in a slightly larger shape than the frame-side Oldham groove 105d. The rocking scroll 102 and the thrust plate 104 are brought into close contact with each other via the lubricating oil 109 to constitute a thrust bearing portion. The thrust plate 104 also has a function of adjusting the clearance in the direction of the rotational drive axis C in the compression chamber 111.

The fixed scroll 101 is formed with spiral teeth 101a erected on the lower surface (back surface) of the base plate. The swing scroll 102 is also provided with spiral teeth 102b that are erected on the upper surface of the base plate and have substantially the same shape as the spiral teeth 101a. The orbiting scroll 102 and the fixed scroll 101 are made of cast iron material, and are mounted in the main body container 100 in a state where the spiral teeth 102b and the spiral teeth 101a are combined with each other. In a state where the swing scroll 102 and the fixed scroll 101 are combined, the winding directions of the spiral teeth 101a and the spiral teeth 102b are opposite to each other. A compression chamber 111 whose volume changes relatively is formed between the spiral tooth 10a and the spiral tooth 9a.

The fixed scroll 101 is fixed to the opening edge of the upper surface of the frame 105 with a bolt or the like (not shown). On the other hand, a hollow cylindrical boss portion 102c is suspended substantially at the center of the bottom surface of the orbiting scroll 102, and the inner peripheral surface of the boss portion 102c is an orbiting bearing 102a. Then, an oscillating-side Oldham groove 102d that guides the upper surface protrusion 103a of the Oldham ring 103 is formed long in the radial direction at an outer position of the boss portion 102c on the lower surface of the oscillating scroll 102 (see FIG. 2). The rocking scroll 102 performs a revolving orbiting motion (so-called rocking motion) without performing the rotational motion with respect to the fixed scroll 101 by the Oldham ring 103 for preventing the rotational motion.

An eccentric shaft portion 110 provided at the upper end of the rotary drive shaft 114 is rotatably inserted into the rocking bearing 102a. The inner peripheral part of the rocking bearing 102a and the outer peripheral part of the eccentric shaft part 110 are slidably brought into close contact with each other via the lubricating oil 109 to constitute the rocking bearing part. The electric motor 115 includes a rotor 106 fixed to the rotation drive shaft 114 and a stator 107 fixed to the inner peripheral surface of the intermediate container. The rotor 106 is driven to rotate when energization to the stator 107 is started, and rotates the rotation drive shaft 114.

The rotation drive shaft 114 rotates with the rotation of the rotor 106 to rotate the swing scroll 102. The upper portion (position near the eccentric shaft portion 10) of the rotation drive shaft 114 is supported by a main bearing portion 105a provided on the frame 105. A ball bearing 117 is attached to the central portion of the sub-frame 116 fixed to the lower inner peripheral surface of the main body container 100, and the lower portion of the rotation drive shaft 114 is rotatably supported by the ball bearing 117. A positive displacement oil pump 108 is attached to the subframe 116. The oil pump 108 is connected to the rotary drive shaft 4 and receives a rotational force. The lubricating oil 109 sucked by the oil pump 108 is sent to each sliding portion through the oil passage hole 114a of the rotary drive shaft 114 and the like.

Next, the operation will be described.
In the scroll compressor configured as described above, when a voltage is applied to the electric motor 115, the rotational drive shaft 114 is rotationally driven, and the eccentric shaft portion 110 rotates within the rocking bearing 102a. Then, the orbiting scroll 102 whose rotation is suppressed by the Oldham ring 103 performs an orbiting orbiting motion. Thereby, a part of the refrigerant gas flows into the compression chamber 111 through the suction port of the frame 105, and the suction process is started. Further, the remaining part of the refrigerant gas passes through the notch portion of the stator 106 and cools the electric motor 115 and the lubricating oil 109.

The compression chamber 111 gradually moves to the center of the orbiting scroll 102 by the orbiting motion of the orbiting scroll 102, and the volume is further reduced. Through this process, the refrigerant gas sucked into the compression chamber 111 is compressed. At this time, a load that moves away from the fixed scroll 101 in the direction of the axis C is applied to the orbiting scroll 102 by the compressed refrigerant gas, and this load is received by the upper surface 104 a of the thrust plate 104. The compressed refrigerant passes through the discharge port of the fixed scroll 101 and is discharged from the main body container 100 to the refrigerant circuit through the discharge pipe 25. In addition, the lubricating oil 109 sucked up to the eccentric shaft portion 110 by the oil pump 108 is generated between the sliding portion of the bearing metal of the orbiting scroll 102, the thrust surface 102e of the orbiting scroll 102, and the upper surface 104a of the thrust plate 104. Lubricate the sliding part. Thereafter, a part of the lubricating oil 109 rises from the outer peripheral edge of the orbiting scroll 102 and enters the compression chamber 111 to lubricate the sliding portions of the spiral teeth 101 a and the spiral teeth 102 b, and the rest downward from the frame 105. And return to the oil sump at the bottom of the main body container 100.

In the scroll compressor configured as described above, the lubricating oil 109 flows from the rocking scroll Oldham groove 102d to the circumferential groove 102f each time the rocking scroll 102 reciprocates along the rocking Oldham groove 102d. A sufficient amount of lubricating oil 109 is supplied from the circumferential groove 102f to the thrust surface 102e. Further, since the thrust plate 104 has the notch 104b, the lubricating oil 109 is supplied from the frame-side Oldham groove 105d to the thrust surface 102e every time the Oldham ring 103 reciprocates along the frame-side Oldham groove 105d. A flow path is secured. In the prior art, the notch 104b as described above was not formed in the thrust plate, which caused an obstacle to supply of lubricating oil from the frame-side Oldham groove to the thrust surface.

As described above, according to the scroll compressor of this embodiment, the supply amount of the lubricating oil 109 to the thrust surface 102e can be increased, and a large oil film pressure can be generated due to the wedge effect generated thereby. As a result, wear and seizure of the thrust surface 102e of the orbiting scroll 102 can be suppressed.

Embodiment 2. FIG.
In the first embodiment, the bottom surface of the orbiting scroll is formed on a horizontal surface without being inclined, but the scroll compressor of the present invention is not limited to this. For example, as shown in FIG. 5, Embodiment 2 in which the thrust surface 102g of the orbiting scroll 102A supported by the upper surface 104a of the thrust plate 104 is formed as an inclined surface that descends radially outward is also included in the present invention. It is.

According to the swing scroll 102A having the inclined thrust surface 102g as described above, an even greater wedge effect can be achieved, so that a larger oil film pressure can be generated. Thereby, wear and seizure of the thrust surface 102e of the orbiting scroll 102 can be reliably prevented.

DESCRIPTION OF SYMBOLS 100 Main body container 101 Fixed scroll 102,102A Swing scroll 102a Swing bearing 102c Boss part 102d Swing side Oldham groove 102e, 102g Thrust surface 102f Circumferential groove 103 Oldham ring 104 Thrust plate 104b Notch 105 Frame 105a Main bearing part 105b Recessed portion 105c Thrust support surface 105d Frame-side Oldham groove 108 Oil pump 109 Lubricating oil 110 Eccentric shaft portion 111 Compression chamber 114 Rotating drive shaft 114a Oil passage hole C Axis center

Claims

A main body container which is a sealed container;
A fixed scroll fixed to the upper part in the main body container;
An orbiting scroll made of cast iron-based material that is arranged below the fixed scroll and forms a compression chamber together with the fixed scroll and has a boss portion at the center of the lower surface,
A rotary drive shaft having an oil passage hole which is formed at an upper end portion of an eccentric shaft portion rotatably supported by a rocking bearing of a boss portion of the rocking scroll and communicates vertically with the shaft;
A thrust support surface that receives the orbiting scroll, a recess that is formed on the inner side of the thrust support surface in the radial direction of the container and accommodates the boss portion of the orbiting scroll, and a rotary drive shaft that is formed below the recess. A frame having a main bearing portion that rotatably supports the frame and fixed to the inner peripheral surface of the main body container;
A thrust plate made of a steel plate material in the form of a ring plate disposed between a lower surface of the swing scroll and a thrust support surface of the frame and slidably supporting the lower surface of the swing scroll;
An Oldham ring that is housed in a recess of the frame and restricts rotation of the orbiting scroll around the rotational drive axis;
An oscillating-side Oldham groove that is formed on the lower surface of the oscillating scroll outside the boss portion and guides the Oldham ring,
A scroll compressor characterized in that a circumferential groove communicating with the rocking Oldham groove is formed on a lower surface of the rocking scroll.
2. The scroll compressor according to claim 1, wherein the thrust surface of the orbiting scroll supported by the upper surface of the thrust plate is formed as an inclined surface that descends radially outward.
A frame-side Oldham groove for guiding the Oldham ring is formed in the recess of the frame, and a notch communicating with the frame-side Oldham groove is formed in the thrust plate at a position facing the frame-side Oldham groove. The scroll compressor according to claim 1 or 2, characterized by the above-mentioned.