JPH0127276B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary compressor used in refrigerators and the like, and its purpose is to reduce noise.

When a conventional rotary compressor is used in a refrigerator or the like, a vacuum is created on the suction side when the compressor is started, and during that time the roller collides with the cylinder, resulting in a strong collision noise. In other words, Figure 1,
In Fig. 2, 1 is a sealed case, 2 is an electric motor section, and at the bottom thereof are a cylinder 3, a roller 4,
Compression element 10 composed of crankshaft 5, vane 6, upper bearing 7, lower bearing 8 and cover 9
is fixed. Further, a compression chamber 11 is formed inside the cylinder 3 by the roller 4 and the vane 6. or,
The vane 6 has a vane spring 12 on its side opposite to the roller 4.
and is pressed against the roller 4. The cylinder 3 has a suction hole 13, and the lower bearing 8 has a discharge hole 14. 15 is a discharge valve, 16 is a discharge chamber covered with a cover 9,
17 is a hole that communicates between the discharge chamber 16 and the interior space 18 of the case 1. 19 is refrigerating machine oil.

In this configuration, while the compressor is stopped, the refrigerant dissolves in the refrigerating machine oil 19, and when the compressor is started, the system temporarily runs out of refrigerant gas and the suction pressure becomes vacuum. Therefore, after the top portion 4a of the roller 4 passes the vane, the roller 4 is separated from the roller 4 and the eccentric portion 5.
It moves in the normal direction by the centrifugal force during rotation by the clearance of a, collides with the inner wall 3a of the cylinder,
This may cause an unpleasant collision sound. To avoid this collision, increase the top clearance between cylinder 3 and roller 4, and
must be dimensioned so that they do not collide, but this will significantly reduce compression efficiency and is not desirable from the perspective of energy efficiency.

The present invention solves these problems and aims at reducing noise without reducing compression efficiency.

An embodiment of the present invention will be described in detail below with reference to FIGS. 3, 4, and 5. In order to avoid duplication of explanation, the same parts as in the conventional example are given the same reference numerals, and the explanation will be omitted. On the sliding surface 5b in the radial direction of the eccentric portion 5a of the crankshaft 5, a large number of extremely shallow approximately V-shaped grooves 5d having a reversed portion in the counter-rotation direction are formed over the entire circumference by, for example, etching. be.

FIG. 6 shows another embodiment in which the groove 5d is removed on a surface located within ±20° from the line portion 5c of the maximum eccentricity.

With this configuration, the refrigerating machine oil sucked into the cylinder is sucked toward the center of the sliding surface 5b by the groove 5d, but since the groove 5d has a V-shape, the oil becomes compressed and the oil is compressed, and the oil is compressed. 4 exerts a large pressure pushing it outward in the normal direction. Therefore,
At startup, when the low-pressure side becomes a vacuum and the roller 4 is attracted to the cylinder inner wall 3a side, and a centrifugal force is applied to the roller 4, even if the roller 4 attempts to move in the centrifugal direction due to the combined force of these forces, it will not move in a V-shape. The clearance between the roller 4 and the eccentric portion 5a appears to be extremely small due to the oil pressure in the shaped groove 5d, and furthermore, if the groove is formed excluding the maximum eccentric portion, the hydraulic pressure applied to the roller 4 will be reduced compared to the maximum eccentric portion. This means increasing the minimum eccentricity side.
Movement of the roller 4 in the centrifugal direction can be further prevented. Therefore, there is no need to increase the top clearance to avoid collision between the roller 4 and the cylinder 3, and efficiency can be improved.

As described above, the present invention houses a compression element composed of a crankshaft, a roller, and a cylinder, and an electric motor directly connected to the crankshaft in a case, and a counter-rotating force is applied to the radial sliding surface of the eccentric part of the crankshaft. This is a roughly V-shaped groove with a reversed section in the direction, and the hydraulic pressure generated within this groove is used to obtain the same effect as if the clearance between the roller and eccentric section were reduced, and the centrifugal force is constantly reduced. It is possible to reduce the amount of movement of the roller in the centrifugal direction due to the resultant force such as the differential pressure caused by the difference in the outer circumferential pressure, and to reduce the top clearance between the roller and the cylinder, thereby improving efficiency.

Furthermore, if the grooves are formed in the eccentric part so as to exclude the largest eccentric part, the movement of the roller in the centrifugal direction can be further reduced. Therefore, the noise of the rotary compressor, especially the noise at the time of startup, can be reduced without reducing the efficiency.

[Brief explanation of drawings]

Figure 1 is a sectional view showing a conventional example of a rotary compressor.
2 is a cross-sectional view taken along line -' in FIG. 1, FIG. 3 is a cross-sectional view of a rotary compressor showing an embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line -' in FIG. FIG. 5 is a front view of the crankshaft seen from the side of the maximum eccentricity of the crank portion, and FIG. 6 is a front view of the crankshaft showing another embodiment corresponding to FIG. 5. 1...Case, 5...Crankshaft, 4...
...Roller, 2...Electric motor section, 3...Cylinder,
10... Compression element, 5a... Eccentric part, 5d...
groove.

Claims (1)

[Scope of Claims] 1. A compression element having a crankshaft, a roller slidably attached to the outer periphery of an eccentric portion of the crankshaft, a cylinder in which the roller is rotatably housed, and the crankshaft A rotary compressor that houses an electric motor directly connected to the crankshaft, and is provided with an extremely shallow substantially V-shaped groove having an inverted portion in the counter-rotational direction on the radial sliding surface of the eccentric portion of the crankshaft. 2. Claim 1, wherein the groove is provided except for the maximum eccentric portion of the radial sliding surface of the eccentric portion.
The rotary compressor described in Section 1.