JPH05340370A - Enclosed compressor - Google Patents

Abstract

PURPOSE:To improve lubrication for an eccentric shaft part and a piston by disposing a circular groove having a large eccentricity to the center shaft of a crankshaft compared with the eccentric shaft part and having a diameter larger than that of the eccentric shaft part in the eccentric shaft part of the crankshaft constituting a compression element. CONSTITUTION:When a motor element 4 in an enclosed container 1 is driven, a rotor 3 is rotated while a piston 8 is operated through a crankshaft 6 so that refrigerant is sucked into a cylinder 9, compressed and then discharged. Also, oil on the bottom in the enclosed container 1 rises to lubricate respective slide parts as the crankshaft 6 rotates. Further, oil discharged from an eccentric shaft part 7 of the crankshaft 6 fills a notch disposed in the eccentric shaft part 7 to lubricate smoothly a clearance between the eccentric shaft part 7 and the piston 8. That is, in the eccentric shaft part 7 is disposed the notch formed eccentrically to the center shaft of the crankshaft 6 with the eccentricity larger than that of the eccentric shaft part 7 and having a diameter larger than that of the eccentric shaft part 7 in the direction of reducing the load on the eccentric shaft part 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic compressor that constitutes a refrigeration cycle, and more particularly to the structure of its crankshaft.

[0002]

2. Description of the Related Art Conventionally, in a crankshaft of a hermetic compressor for an air conditioner or the like, a part of the eccentric shaft has been cut out in order to lubricate a gap between the piston and the eccentric shaft with oil.

The structure of a conventional example will be described below with reference to FIGS. An electric motor element 4 including a stator 2 and a rotor 3 and a compressor element 5 driven by a crankshaft 6 by the electric motor element 4 are arranged inside the hermetic container 1 to form a hermetic compressor. Is composed of.

The compressor element 5 includes the crankshaft 6
A piston 8 fitted to the eccentric shaft 7 of the crankshaft, a cylindrical cylinder 9 for accommodating the piston 8, an upper bearing end plate 10 for closing both end openings of the cylinder 9, and a lower bearing. It is constituted by the end plate 11. The upper and lower bearing end plates 10 and 11 respectively form a pair and also support the crankshaft 6.

As shown in FIG. 5, the crankshaft 6 is made up of three parts, an upper shaft 12, an eccentric shaft 7, and a lower shaft 13, and is a hollow shaft. Further, blades 14 are inserted inside the crankshaft 6 and oil holes 15 communicating with the hollow shaft are provided.

Further, the eccentric shaft 7 of the crankshaft is
In addition to the oil hole 15, a notch 16 parallel to the axial direction of the crankshaft 6 is provided.

The operation of the conventional hermetic compressor constructed as above will be described. When the electric motor element 4 is operated, the refrigerant is drawn into the cylinder 9 and the piston 8
The refrigerant that is compressed by the rotation of the
Is discharged inside. In addition, the oil (not shown) at the bottom of the closed container 1 causes centrifugal force of the oil as the crankshaft 6 rotates.
By the action of the blades 14 provided in the crankshaft, the blades go up in the crankshaft, come out from the oil holes 15 provided in the crankshaft 6, and lubricate the sliding parts. In particular, the oil flowing out from the oil hole 15 provided in the eccentric shaft 7 lubricates the space between the piston 8 fitted in the eccentric shaft 7 by the notch 16 provided in the eccentric shaft 7 of the crankshaft 6. ..

[0008]

However, in the notch 16 as described above, the sliding area between the eccentric shaft 7 of the crankshaft 6 and the piston fitted thereto is large, and the eccentric shaft 7 and the piston 8 are However, there was a problem that the sliding loss was large.

Further, in the conventional structure, the oil distribution is not uniform in the gap between the eccentric shaft 7 and the piston 8, and the wear of the eccentric shaft 7 increases and, in the worst case, seizure occurs. Had challenges.

In view of the above problems, the present invention provides a shaft of a hermetic compressor having a large notch provided on a sliding surface of a shaft eccentric shaft with respect to a piston.

[0011]

In order to solve the above problems, the present invention provides a circular groove on the side of the eccentric shaft of the crankshaft where the load is low, and provides a notch that is stepped down with respect to the eccentric shaft. It is a thing.

[0012]

According to the present invention, the sliding area of the portion of the crankshaft to which a large load is applied is the same as that of the conventional one.
It is possible to prevent wear by reducing the sliding area of a portion having a small load and a sufficient margin, reducing the sliding loss of the crankshaft, and increasing the lubricating action of oil as compared with the conventional case.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

The same parts as those of the above-mentioned conventional example are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 shows a main part of a hermetic compressor showing an embodiment of the present invention. The present invention uses the eccentric shaft 7 of the crankshaft 6.
In addition, a notch that is larger than the eccentric amount of the eccentric shaft 7 and eccentric from the central axis of the crankshaft 6 and larger than the outer diameter of the eccentric shaft 7 is provided in the direction in which the load of the eccentric shaft 7 is small.

The operation of the above structure will be described below. When the electric motor element 4 is operated, the rotor 3 is driven, the piston 8 is driven via the crankshaft 6 in accordance with the drive of the rotor 3, and the refrigerant in the cylinder 9 is rotated as the piston 8 rotates. Is inhaled, compressed and discharged.

The oil in the bottom of the closed container 1 rises in the crankshaft 6 due to the centrifugal force of the crankshaft 6 and the action of the blades 14 provided inside the crankshaft 6 as the crankshaft 6 rotates. The oil going up inside the crankshaft 6 goes out of the crankshaft 6 through an oil hole 15 provided in the crankshaft 6 on the way, and lubricates each sliding portion. The oil discharged from the oil hole 15 provided in the eccentric shaft 7 is
Is filled in the notch provided in and the lubrication is smoothly performed in the gap between the piston 8 and the eccentric shaft 7. Further, the lubrication of the oil is smooth, and at the same time, the sliding area with the piston 8 is reduced, and the sliding loss due to the viscosity of the oil can be reduced, so that the sliding loss between the eccentric shaft 7 and the piston 8 is reduced. Can be reduced. In addition, the smooth lubrication causes the eccentric shaft 7
It is also possible to prevent an increase in wear.

[0018]

As described above, according to the present invention, by providing the circular stepped notch on the low load side of the eccentric shaft of the crankshaft, the lubrication between the eccentric shaft and the piston is made smooth, and the viscosity of the oil depends on the viscosity of the oil. The sliding loss and the effect of reducing the sliding loss by reducing the sliding loss are exhibited. Further, the smooth oil lubrication also has the effect of preventing abnormal wear and seizure of the crankshaft eccentric portion.

[Brief description of drawings]

FIG. 1 is a sectional view of a hermetic compressor showing an embodiment of the present invention.

FIG. 2 is a side view of the crankshaft.

3 is a sectional view taken along the line AA of FIG.

FIG. 4 is a perspective view of the crankshaft.

FIG. 5 is a side view of a conventional crankshaft.

FIG. 6 is a vertical sectional view of the compressor.

[Explanation of symbols]

 1 Airtight container 4 Electric motor element 5 Compressor element 6 Crankshaft 7 Eccentric shaft 8 Piston

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Muramatsu 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. An electric motor element and a compressor element driven by the electric motor element are respectively provided in a hermetically sealed container, and an eccentric shaft of a crankshaft constituting the compressor element is provided on an eccentric shaft as compared with the eccentric shaft. A hermetic compressor characterized in that a circular groove having a large eccentricity with respect to a central axis of the shaft and having a diameter larger than a diameter of the eccentric shaft is provided. 2. The hermetic compressor according to claim 1, wherein the width of the circular groove is smaller than the width of the eccentric shaft. 3. The hermetic compressor according to claim 1, wherein the circular groove is formed at a position where the surface pressure applied to the crankshaft is small.