JPH0557435B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a scroll compressor used in a refrigerant compressor, etc., and particularly relates to prevention of damage to a thrust bearing of an oscillating scroll.

[Conventional technology]

The basic elements and compression principle of this type of scroll compressor are illustrated in FIG. 4.
A fixed scroll 1 is provided with a spiral protrusion 1a. Reference numeral 2 denotes an oscillating scroll, which is provided with a spiral protrusion 2a, and is assembled with a phase shift of 180 degrees with respect to the fixed scroll 1, and rotates around a fixed point P of the fixed scroll 1 and around a fixed point Q on the oscillating motion. Swings as a base point.

As shown in FIGS. 4a to 4d, the oscillating scroll 2 is caused to revolve around a fixed point P at 0°, 90°, 180°, and 270°. As a result, the spiral protrusion 1a,
A crescent-shaped compression chamber 5 formed between 2a sucks fluid from the suction port 3 side, moves sequentially toward the center along the spiral, gradually reduces its volume and compresses the fluid inside, and the fixed scroll 1 from the outlet 4 in the center.

Next, the specific configuration of main parts of the scroll compressor will be explained. FIG. 5 is a sectional view of a main part of a conventional scroll compressor disclosed in, for example, Japanese Patent Laid-Open No. 57-173585. A spiral projection 1a is projected from the base plate 1b of the fixed scroll 1, and a spiral projection 2a is projected from the base plate 2b of the oscillating scroll 2, and both spiral projections are shifted in phase by 180 degrees. 2c is a shaft portion projecting downward from the base plate 2b, 3 is an inlet, 4 is a discharge port, and 6 is a bearing frame, which fixes the fixed scroll 1 and holds the thrust bearing 7. Oil grooves 7a are provided radially on the upper surface of the bearing 7. Reference numeral 8 denotes an eccentric shaft that is rotated by a drive source (not shown) such as an electric motor, and is supported by the bearing frame 6 through a sleeve bearing 9 at the large diameter outer circumference of the shaft end 8a. An eccentric hole 8b is provided, and the swinging drive is transmitted to the shaft portion 2c of the swinging scroll 2 via the sleeve bearing 10. Reference numeral 8c denotes an oil hole provided eccentrically from the shaft center on the eccentric shaft 8, and guides lubricating oil sucked from below upward. Reference numeral 11 denotes an Oldham joint that stops the rotation of the oscillating scroll 2, and 12 a counterbalance weight attached to the eccentric shaft 8, which balances the eccentric revolution of the oscillating scroll 2.

In the conventional device described above, the eccentric shaft 8 is
is rotationally driven, and the swinging scroll 2 is swinged and revolves. In this way, the suction fluid is compressed by the action shown in FIG. 4 and is forcefully delivered from the discharge port 4.

In this case, thrust acts on the rocking scroll 2 due to the pressure of the compressed fluid in the compression chamber 5, but this is received by the thrust bearing 7.

[Problem that the invention seeks to solve]

In the conventional scroll compressor as described above, the back surface (lower surface) of the oscillating scroll 2 due to thrust
In order to prevent seizure and abnormal wear with the thrust bearing 7, high-precision surface finishing must be performed, and cutting and super-finishing machining are troublesome and require advanced technology, and a large amount of work is required. The problem was that it took time.

Furthermore, when the material of the swinging scroll 2 is cast iron, it is difficult to control the hardness, and when the structure contains a large amount of ferrite phase, the hardness is low and seizure with the thrust bearing 7 may occur.

In order to cope with this problem, heat treatment is performed to increase the hardness of the oscillating scroll 2, but there are problems such as thermal strain and deformation, and high hardness that makes cutting difficult.

This invention was made to solve these problems, and it eliminates seizure and abnormal wear of the orbiting scroll and thrust bearing, improves reliability, and improves reliability.
There is no need for conventional high-precision cutting or super-finishing polishing of the back (lower surface) of the oscillating scroll, there is no need for sophisticated control of the hardness and structure of the oscillating scroll material, and there is no need for heat treatment. The objective is to obtain a scroll compressor with improved workability.

[Means for solving problems]

In the scroll compressor according to the present invention, a cover plate made of a hard metal material is attached to the lower part of an oscillating scroll so as to swing together with the scroll, and this cover plate is supported by a thrust bearing.

[Effect]

In this invention, the oscillating scroll is supported by a thrust bearing through a backing plate placed on the bottom surface, and the backing plate is made of a hard metal material and has the highest surface roughness, has wear resistance, and can be used for a long time. be done.

〔Example〕

FIG. 1 shows an embodiment of a scroll compressor according to the present invention. It is an exploded perspective view of an oscillating scroll thrust bearing part, and 2, 2a-2c, 7, and 7a are the same as the said conventional apparatus. Reference numeral 21 denotes a backing plate made of a hard metal plate such as a hard steel plate, and is provided with a plurality of ears 21a bent upward and provided with screw holes 21b. On the side surface of the base plate 2b of the swinging scroll 2, a plurality of flat counters 2d into which the ears 21a are fitted are formed at corresponding locations, and screw holes 2e are formed on the side surface of the base plate 2b.
is provided. A backing plate 21 is placed on the back surface of the swinging scroll 2 and is attached with a mounting screw 22 so as to swing together, and is received by a thrust bearing 7.

In the apparatus of the above embodiment, the swinging scroll 2 swings and revolves, and is supported by the thrust bearing 7 via the backing plate 21. The backing plate 21 has high hardness, has a dense structure, has a smooth surface with the highest level of roughness, has wear resistance, and is supported with smooth lubrication.

FIGS. 2 and 3 are exploded perspective views of an oscillating scroll and a cover plate showing other different embodiments of the present invention.

In FIG. 2, reference numeral 23 denotes a backing plate made of a high-quality metal plate such as a hard steel plate, through which a countersunk screw 24 is passed, and a countersunk hole 23a into which the head is sunk is bored. This backing plate 23 is placed against the lower part of the swinging scroll 2, and is screwed into the threaded hole 2f of the swinging scroll 2 with a countersunk screw 24 to be attached.

In Fig. 3, a patch plate 2 made of a hard metal plate is shown.
5 is provided with three or more ears 25a bent upward at equal intervals. On the side of the base plate 2b of the swinging scroll 2, a flat seat 2d into which the ear portion 25a is fitted is provided at a corresponding position. The backing plate 25 is applied to the lower part of the swinging scroll 2, and the ear portion 25a is fitted into the flat seating 2d, so that it is received by the swinging scroll 2 in the circumferential direction. Since the backing plate 25 receives the load of the swinging scroll 2 from above and is supported by the thrust bearing 7 on the bottom surface, it swings together with the swinging scroll 2 while being in contact with the swinging scroll 2, and does not come off.

If the configurations shown in Figures 1 and 3 are used, lubricating oil will infiltrate into the minute gap created between the bottom surface of the oscillating scroll and the top surface of the backing plate, causing abnormalities that occur for some reason during compressor operation. It has the effect of damping pressure.

In the embodiment shown in FIG. 2, the cover plate 23 is attached to the lower part of the swinging scroll 2 from below with the countersunk screws 24. 2 may be provided with holes for pins into which these fixing pins are fitted.

In addition, in the embodiment shown in FIG. It may be attached by hugging the upper part of the base plate 2b.

〔Effect of the invention〕

As described above, according to the present invention, a backing plate made of a hard metal material is attached to the lower part of the oscillating scroll so that they can oscillate together, and the back surface of the oscillating scroll is received by a thrust bearing. does not require high-precision super-finishing as in the past, does not require advanced control of the material's hardness and structure, eliminates the need for heat treatment, facilitates quality control, improves workability, and shakes Seizure and abnormal wear of the moving scroll and thrust bearing are prevented.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a thrust bearing portion of an oscillating scroll showing one embodiment of a scroll compressor according to the present invention, and FIGS. 2 and 3 are oscillating scrolls showing other different embodiments of the invention. FIG. 4 is an explanatory diagram sequentially showing the basic structure and compression principle of a scroll compressor, and FIG. 5 is a longitudinal sectional view showing the main parts of a conventional scroll compressor. 1... Fixed scroll, 1a... Spiral protrusion, 1
b... Base plate, 2... Oscillating scroll, 2a... Spiral protrusion, 2b... Base plate, 3... Suction port, 4... Discharge port, 5... Compression chamber, 6... Bearing frame, 7 ... Thrust bearing, 8 ... Eccentric shaft, 21 ... Backing plate, 2
3, 25...Packing plate. In addition, the same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A fixed scroll having a spiral protrusion on one side of the base plate, and a spiral protrusion on one side of the base plate being eccentrically combined with the spiral protrusion of the fixed scroll, are eccentrically revolved, and are rotated from the outside suction side. an oscillating scroll for forming a compression chamber for fluid and moving it toward the center and forcing out the compressed fluid from a discharge port; a rotation drive means for rotating an eccentric shaft to oscillate the oscillating scroll; and a bearing frame. A scroll compressor is provided with a thrust bearing that is held and supports the oscillating scroll from the rear side, which is made of a hard metal plate and is attached to the back surface of the oscillating scroll so as to swing together with the oscillating scroll. A scroll compressor characterized by being equipped with a backing plate that is swingably supported by a thrust bearing.