JP2510639B2 - Rotary type hermetic compressor - Google Patents

Description

The present invention relates to a rotary hermetic compressor, and more particularly to a structure suitable for improving reliability.

[Conventional technology]

A conventional rotary hermetic compressor will be described with reference to FIGS. 4 and 5. FIG. 4 is a vertical sectional view of the rotary compressor, and FIG. 5 is a sectional view of the cylinder portion of FIG. In the figure, an electric element 2 is arranged in the upper part of a closed container 1, and a compression element 3 is arranged in the lower part. The electric element 2 comprises a stator 4 and a rotor 5. The compression element 3 includes a shaft 6, an upper bearing 7 and a lower bearing 8 that hold the shaft 6, a cylinder 9 sandwiched between the upper bearing 7 and the lower bearing 8, and a shaft 6.
Roller 10 rotatably fitted to the eccentric part (not shown) of
And a vane 11 pressed against the roller 10 in the chamber of the Silytan 9. The refrigerant gas sucked from the suction pipe (not shown) enters the compression element 3 and is gradually compressed by the rotation of the roller 10 to become a high pressure, and then passes through a valve (not shown) to form a high-pressure sealed type container. It is discharged into the container 1, and further discharged from the discharge pipe 13 into a cycle (not shown).

In this structure, in general, when the refrigerating capacity is reduced, the size of the cylinder remains constant and the eccentric dimension of the shaft eccentric portion is reduced. Reducing the eccentric dimension of the shaft eccentric portion reduces the pushing amount per one rotation of the roller, that is, increases the outer diameter of the roller 10. Therefore, the wall thickness t of the roller 10 becomes large. When the wall thickness t of the roller 10 becomes large, the innermost locus 15 of the outer diameter of the roller 10 becomes larger in diameter than the outermost locus 14 of the inner diameter of the roller 10, as shown in FIG. During the period of 15, the roller 10 and the lower bearing 8 always slide. Therefore, since the lubricating oil in that range is difficult to move, the heat escape is poor, and the temperature inside the cylinder chamber 16 tends to become high.

As a means for reducing the amount of pushing, for example, Japanese Patent Publication No. 58-361
As in 96, there is a means for reducing the eccentric dimension of the shaft eccentric portion while keeping the radial contact width of the roller end surface with the cylinder side plate constant.

[Problems to be solved by the invention]

The prior art does not consider the optimum value of the wall thickness of the roller 10 with respect to the eccentric amount of the eccentric part of the shaft 6,
Lubrication oil may accumulate between the lower bearing 20 and the lower bearing 8, and foreign matter may accumulate and wear may occur.

An object of the present invention is to provide a rotary compressor that prevents accumulation of lubricating oil and occurrence of wear.

[Means for solving problems]

The above-mentioned object is to arrange an electric element and a compression element in the lower part of the closed container, and the compression element holds the cylinder at the flange end surfaces of the upper bearing and the lower bearing that hold the shaft,
A rotary hermetic compressor in which a roller rotatably fitted to the eccentric portion of the shaft rotationally compresses in the cylinder, and the wall thickness of the roller is larger than twice the eccentric dimension of the shaft eccentric portion. A taper or step is formed on the end surface of the roller that is in contact with the flange end surface of the upper bearing, the lower bearing, or both bearings, and the radial contact width between the end surface of the roller and the flange end surface of the upper bearing, the lower bearing, or both bearings. Is smaller than twice the eccentric dimension so that there is no contact surface between the end surface of the roller and the flange end surface of the upper bearing or the lower bearing or both of the bearings that is constantly in contact with and continues to slide. Achieved by

[Action]

Since the locus 14 of the outermost point on the inner diameter side of the roller is outside the locus 15 of the innermost point on the outer diameter side of the roller, the shaft of the lubricating oil between the roller and the lower bearing rotates once. The outer diameter of the roller is wiped outward, and the inner diameter is wiped inward, so that it is discharged from the cylinder chamber with the gas when it is moved to the outside, and the oil groove (not shown) of the shaft is moved when it is moved to the inside. It merges with the flowing lubricating oil and is discharged from the upper end of the upper bearing and the lower end of the lower bearing into the sealed container. Therefore, the lubricating oil does not accumulate between the roller and the lower bearing.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. 1 is a sectional view of a main part of a rotary hermetic compressor, and FIG. 2 is a sectional view taken along the line AA of FIG. In addition, the same reference numerals as those in FIGS. 4 and 5 indicate equivalents or the same. In the figure, the roller 20 is provided with steps 21 and 22 on the inner diameter side without changing the radius R _p of the fitting portion with the eccentric portion of the shaft 6, and the end face contact width l of the roller 20 is the same as that of the shaft and the eccentric portion. It is smaller than twice the eccentric dimension E. According to this structure, the radial contact width l of the roller end surface, the eccentricity E, the roller outer radius
When R _{r is} the cylinder radius R _c , the radius of the locus 14 at the outermost point on the inner diameter side of the roller 10 or 20 is (R _r −l + E). On the other hand, the radius of the locus 15 of the innermost point on the outer diameter side of the roller 10 or 20 is (R _r −E). Where locus 14 and locus
In the area in the range between 15 and 15, it becomes difficult for the lubricating oil to move.

Therefore, in order to lose the area between the loci 14 and 15, the radius of the locus 14 (R _r −l + E) is changed to the radius of the locus 15 (R _r −E).
It is sufficient to make it larger (R _r −E) <(R _r −l + E). Therefore, the contact width l in the radial direction of the roller end surface may be determined so as to satisfy l <2 · E. That is, the relationship between the eccentric dimension E and the contact width l in the radial direction of the roller end surface is set within the range of the region I in FIG.

FIG. 3 is a diagram illustrating the relationship between the contact width of the roller end surface and the eccentric dimension of the present invention, the vertical axis represents the contact width of the roller end surface, and the horizontal axis represents the eccentric dimension. As described above, without changing the radius R _p of the fitting portion with the eccentric portion of the shaft 6, the roller 20
Steps 21 and 22 are provided on the inner diameter side, and the contact width l in the radial direction of the roller end surface is made smaller than twice the eccentric dimension E.

Therefore, there is an effect that it is possible to prevent the lubricating oil from being accumulated between the roller 20 and the lower bearing 8 and becoming high in heat, and the foreign matter such as abrasion powder from being stagnant and causing abnormal wear. Further, there is an effect that it is possible to prevent an increase in sliding loss in the eccentric portion of the shaft 6.

In this embodiment, steps are provided above and below the roller 20, but there is no significant difference in effect even if there is no step because the clearance is large on the upper side. Also, the step can be replaced by a taper.

〔The invention's effect〕

According to the present invention, the end surface of the roller, which is in contact with the flange end surface of the upper bearing or the lower bearing or both of the bearings, is tapered or stepped, and the end surface of the roller and the flange end surface of the upper bearing or the lower bearing or the both end bearings are radially arranged. The contact width is made smaller than twice the eccentric dimension so that there is no contact surface between the end surface of the roller and the flange end surface of the upper bearing or the lower bearing or both of the bearings that is always in contact with and sliding on. There is an effect that it is possible to prevent the lubricating oil from being accumulated between the upper bearing and the lower bearing, or both the bearings, and the foreign matter such as abrasion powder from being accumulated to cause abnormal wear.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a rotary hermetic compressor of an embodiment of the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a roller end surface contact width of the present invention. And FIG. 4 is a vertical sectional view of a conventional rotary hermetic compressor, and FIG. 5 is a sectional view of a main part of FIG. 1 ... Closed container, 2 ... Electric element, 3 ... Compression element,
4 ... Stator, 5 ... Rotor, 6 ... Shaft, 7 ...
Upper bearing, 8 ... Lower bearing, 9 ... Cylinder, 10 ... Roller, 11 ... Vane, 12 ... Low pressure chamber, 13 ... Discharge pipe, 14,1
5 …… Locus, 20 …… Roller, 21, 22 …… Step, 16 …… Cylinder chamber.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Uezuma 4026 Kujimachi, Hitachi, Hitachi, Ibaraki Prefecture Hitachi Research Laboratory Ltd. (72) Yusaku Nakagawa 4026 Kujicho, Hitachi, Hitachi Ibaraki Hitachi, Ltd. In the laboratory (72) Inventor Hiroshi Iwata 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Inside the Home Appliances Research Laboratory, Hitachi, Ltd. (56) References Japanese Patent Publication Sho 58-36196 (JP, B2)

Claims (1)

(57) [Claims] 1. An electric element is disposed on an upper part of a hermetic container, and a compression element is disposed on a lower part thereof. The compression element holds a cylinder between flange end faces of an upper bearing and a lower bearing for holding a shaft, and the eccentricity of the shaft. In a rotary hermetic compressor having a roller that is rotatably fitted in the shaft portion and rotationally compresses in the cylinder, and the wall thickness of the roller is larger than twice the eccentric dimension of the shaft eccentric portion, the upper bearing or the lower bearing The end surface of the roller that is in contact with the flange end surface of the bearing or both bearings is tapered or stepped, and the radial contact width between the end surface of the roller and the flange end surface of the upper bearing or the lower bearing or both bearings is the eccentric dimension. Of the contact surface between the end surface of the roller and the flange end surface of the upper bearing or the lower bearing or both of the bearings, which is in constant contact and continues to slide. Rotary hermetic compressor, characterized in that it has so no.