JPH01211685A - Rotary compressor - Google Patents

Abstract

PURPOSE:To reduce vibration, noise and friction loss on a bearing by forming one of a plurality of balancers attached to a crankshaft as a balancer of which the annular space contains a flowing element. CONSTITUTION:A closed container 1 contains both an electric element part 2 at the upper side and a compressing element part at the lower side. Balancers 16 and 12 are in balance with the eccentric centrifugal force produced by the crank part 8a of a crankshaft 8. A balance 12 of which the internal annular space 12a partially contains a steel ball 13, for example, as a flowing element having a high specific gravity is served as a small balancer. An eccentric adjusting balancer 15 is placed on the rotor 5, and the load of the centrifugal force by said balancer 15 is regulated to the proximity of the centrifugal force produced due to a manufacturing tolerance.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to shaft system balancing of a rotary compressor,
In particular, it is concerned with reducing the wobbling of the shaft system when operating at high speeds.

[Conventional technology]

As shown in FIG. 7, a conventional rotary compressor draws refrigerant gas into a cylinder, compresses it, and discharges it by eccentrically rotating a roller 7 of a compression element part by a crank part 8a of a crankshaft 8. ing. By the way, when the rotary compressor is in operation, centrifugal force is generated between the crank part 8a and the roller 7, causing the crankshaft to oscillate.
Balancers 16 and 17 are provided at both ends of the crankshaft to balance the centrifugal force generated in the crankshaft and reduce the negative load on the crankshaft bearing.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, even if a balancer is provided in the crankshaft system, an unbalance amount constantly occurs due to manufacturing errors, and it is impossible to completely balance the shaft system. For this reason, the centrifugal force due to the above unbalance amount is proportional to the square of the angular velocity, so when the crankshaft is rotated at high speed, the whirling of the shaft system increases, which increases the load on the bearings and causes damage to the bearings. There was a problem with burn-in.

The present invention aims to provide a rotary compressor with high reliability of 11゜, which can automatically eliminate these unbalances caused by manufacturing, reduce whirling during high-speed rotation, and reduce vibration and bearing sliding loss. be.

[Means for deciding issues]

The above problem involves a crankshaft that connects an electric element and a pressure line element housed in a container, a roller fitted to the crank part of this crankshaft, and a centrifugal force between the crank part of the crankshaft and the roller. In a rotary compressor comprising a plurality of counterbalancing balancers, at least one of the plurality of balancers provided on the crankshaft forms an annular space surrounding a 61° C. moving body,
This is achieved by filling this space with a liquid to form a balancer.

[Effect] W. T. THOMSON, translated by Yo Kobori, "Introduction to Mechanical Vibration (6th Edition)" (round tube) (p. 74-p.

75) Aging the model as shown in FIG. 3 as described. That is, the trade Si of the shaft 19 is a rabbit, and the two bearings 2
Consider one disk 18 having an eccentricity of 'tM m m, which is located symmetrically between 0 and 0, rotating at a constant rotational angular velocity W, and ignoring the effects of gravity and friction. It is assumed that the axial center line of the bearing intersects the disk surface at 0, the geometric center S of the disk is cut away from 6 by a distance r, and the center of gravity G of the disk is e away from S. .

Then, the three points O, S, and O are aligned on a straight line, and CIII<W
, , in the range of 0-8-G, ]w>w, , the order is 6-os, and the whirling amount r of the shaft is expressed as, where Wn is the natural angular velocity of the shaft. It is.

From the above equation, if the rotational angular velocity W is constant, the whirling force tr depends on the eccentricity e, and as e becomes smaller, the absolute value of r becomes smaller. When W becomes sufficiently thick, r converges to -e.

Here, as shown in FIG. 4, the rotating disk 18 is a hollow disk 12, and a part of the hollow space is filled with a fluid 13 such as a steel ball, so that the position of the center of gravity G can be changed. do.

Due to centrifugal force, the fluid 13 gathers in the direction of shaft deflection, as shown in the figure. Here, if we compare the case of W)W, , the fifth
As shown in the figure, the center of gravity G' of the fluid is on the opposite side with respect to the center of gravity G of the circular phase and the center S of the hollow disk, and the center of gravity G' of the rotating body as a whole approaches S. As a result, the eccentricity i
When e is small and fi and whirling br become small and match GI or S, r becomes 0, and even if the conventional W becomes a sufficiently large value, if the amount of eccentricity - e remains the amount of whirling ( In comparison, whirling can be reduced in the rotation speed range exceeding W. Fig. 6 shows an example of the effect of the embodiment of the present invention.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIG. In the figure, reference numeral 1 denotes a closed container of a rotary compressor, in which an electric element part 2 is disposed in the upper part and a compression element part is arranged in the lower part. The electric element section 2 is composed of a stator 4 and a rotor 5.

The compression element section is composed of a cylinder 6 and a roller 7 provided within the cylinder 6.

The rotor 5 and the roller are connected to the crankshaft 8.
The roller 7 is eccentrically rotated by the crank ls8a of the crankshaft 8. Further, the crankshaft 8 is rotatably supported by an upper bearing 9 and a lower bearing 10. The interior of the cylinder is divided by vanes 11 into a suction chamber and a discharge chamber.

12 and 13 are balancers, and the crankshaft 8
Balances the eccentric centrifugal force caused by the crank g158a.

The balancer 12 is an example of a small balancer in which a disc-shaped cavity 12a is partially filled with, for example, steel balls 13 having a large specific gravity as a fluid. When the rotation of the crankshaft becomes faster and the deflection of the shaft increases, as mentioned above, it is moved appropriately to eliminate eccentricity of the rotating shaft system, and the runout lc! 1
There will be no more. FIG. 2 shows a modification of the embodiment of the present invention, in which a fluid such as mercury 14 is used instead of the steel balls 13 as the fluid, and the sliding sound of the steel balls 13 is eliminated.

Furthermore, an eccentric blade adjustment balancer 15 is provided on the upper side of the rotor, and the centrifugal type generated by this balancer is made as thick as the centrifugal force generated due to manufacturing errors, thereby achieving miniaturization.

Effects of the invention C] Misfire "9" reduces the eccentricity of the rotating shaft system during high-speed rotation, reduces whirling, and reduces vibration and vibration.
This has the advantage of being able to provide a highly reliable rotary compressor that can reduce the sliding loss of the bearings. It also has the effect of eliminating the conventional design restriction that prevents use at critical speeds near the natural frequency of the shaft system.

4, t"I ml (D Pill single',; l?
Fig. 1 is a rough sectional view of a rotary compressor according to an embodiment of the present invention, Fig. 2 is a perspective view of a rotor showing a modified example of the invention, and Figs. 3 and 4 are illustrations of the original of the present invention. 〃FIG. 5 is a plan view of the disk shown in FIG. 4 viewed from above;
FIG. 6 is an explanatory diagram of an example of the effect of the present firing, and FIG. 7 is a longitudinal sectional view of a conventional rotary compressor.

1... Closed container, 2... Electric element piece Y, 3...
Compression element portion, 4... Stator, 5 - Rotor, 6...
・Cylinder, 7...Roller, 8...Crankshaft, 8a...Crank part of crankshaft, 9...
・Upper bearing, 10...Lower bearing, 11...Vane, 12
... Annular cavity, 12a... Cavity part, 12b...
semicircular ring cavity, 13... steel ball, 14... mercury, 15.
... Balancer for fine adjustment, 16.17 ... Fixed foot balancer, 18 ... Disc, 19 ... Shaft, 20 ... Bearing.

Claims (1)

[Claims] 1. A closed container, a crankshaft that connects the electric element part and the compression element part housed in the closed container, and a roller fitted to the crank part of the crankshaft;
In a rotary compressor comprising a plurality of balancers for offsetting the centrifugal force of the crank portion of the crankshaft and the rollers, at least one of the balancers forms an annular space surrounding the fluid, and a part of the space A rotary compressor, characterized in that a balancer is filled with the fluid described above.