JPH10220368A - Crank shaft for scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a diameter of an eccentric pin as largely as possible while keeping the size of a diameter of a main shaft part of a crank shaft. SOLUTION: An eccentric pin 10 is arranged eccentrically in respect to an axis of a main shaft part 9 of a crank shaft 8 by a value (e) at its center. At the eccentrically arranged position, a diameter D of the eccentric pin 10 has the size at its all outer peripheral area to the extent that is included in a transverse surface profile determined by a diameter Ds of the main shaft part 9. An outer peripheral edge of the eccentric pin 10 is so set as to be projected outside the transverse cross sectional profile of the main shaft part 9, as indicated by (c). The outer peripheral edge projected from the transverse cross sectional profile is removed as a pin escape hole 19, together with an oil groove 18. A shape indicated by (a) is thus obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly to a crankshaft suitable for increasing the rigidity of an eccentric pin portion which engages a movable scroll via a swing link.

[0002]

2. Description of the Related Art A scroll compressor used in an air conditioner or the like is provided with a fixed scroll having a spiral wrap for forming a space for compressing a refrigerant gas and a movable scroll. The two scrolls are eccentrically combined, and the movable scroll, which is a movable element, revolves and compresses the refrigerant gas drawn into the compression space. In order to maintain an eccentric position with respect to the fixed scroll, the orbiting scroll is engaged with an eccentric pin portion which is eccentric with respect to the axis of the crankshaft arranged at the center of the case.

[0003] During the operation of the compressor, a high pressure due to the refrigerant gas is applied to the eccentric pin portion engaged with the movable scroll, together with the inertial force from the orbiting movable scroll. The eccentric pin must have sufficient rigidity to prevent bending due to these external forces.However, the outer periphery of the eccentric pin located at a position eccentric with respect to the main shaft of the crankshaft crosses the main shaft. If it exceeds the surface contour,
The compressor is configured as a relatively small diameter shaft that does not exceed the cross-sectional profile because assembly and disassembly of the compressor becomes difficult.

[0004]

As described above, in order to resist the external force acting on the eccentric pin portion of the crankshaft, the outer peripheral portion of the eccentric pin portion is formed so as to protrude largely outside the cross-sectional profile of the main shaft portion. In this case, the assembly and disassembly of the compressor become practically difficult, so that the diameter dimension of the eccentric pin portion is limited so as to fall within the cross-sectional profile. Under these constraints, one possible solution is to increase the diameter of the main shaft of the crankshaft more than ever. However, such a redundant solution has too great disadvantages, such as an increase in the weight of the crankshaft as a rotating body and an increase in motor power.

Accordingly, an object of the present invention is to provide a crankshaft for a scroll compressor in which the diameter of an eccentric pin portion can be made as large as possible while keeping the main shaft portion diameter of the crankshaft unchanged.

[0006]

According to a first aspect of the present invention, there is provided a crankshaft for a scroll compressor having an eccentric pin portion eccentric to an axis of a main shaft portion, wherein the eccentric pin portion is a shaft of the main shaft portion. Only a part of the outer peripheral edge in the direction eccentric with respect to the center has a pin diameter determined to project slightly out of the cross-sectional profile of the main shaft portion, and the outer peripheral edge of the eccentric pin portion outside the cross-sectional profile is It is characterized by being removed and formed as an eccentric pin portion having a final shape.

The invention according to claim 2 is characterized in that the outer peripheral edge of the eccentric pin portion outside the cross-sectional profile of the main shaft portion is removed simultaneously with the oil groove on the outer surface of the main shaft portion. Is what you do.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 2, the scroll compressor has a fixed scroll 1 and a movable scroll 2 each having a spiral wrap. This fixed scroll 1
And the movable scroll 2 are eccentrically combined to form a space 3 for compressing the refrigerant gas, and the fixed scroll 1 is provided at a fixed interval between the fixed scroll 1 and the frame 5 fixed to the case 4. Reference numeral 2 denotes a lower surface that is in contact with the frame 5.

Further, a crankshaft 8 supported by a bearing 6 mounted on the frame 5 and a bearing plate 7 is provided at the center of the case 4. The crankshaft 8 includes a main shaft portion 9 and an eccentric pin portion 10. A motor 11 as a power means is fixed to the main shaft portion 9, and the movable scroll 2 is engaged with the eccentric pin portion 10 via a swing link 12. Have been.

The movable scroll 2 is provided with an Oldham ring 13 for changing the rotating operation of the crankshaft 8 into the revolving motion of the movable scroll 2. The Oldham ring 13 is provided with a key 14 provided on the upper surface of the movable scroll 2.
And a key 16 provided on one lower surface.
Are fitted in the key groove 17 of the frame 5, and the movable scroll 2 revolves while the Oldham ring 13 and the movable scroll 2 relatively move during rotation of the crankshaft 8.

FIG. 1 shows a crankshaft 8 according to the present invention. The center of the eccentric pin 10 formed at the end of the crankshaft 8 is eccentric with respect to the axis of the main shaft 9 of the crankshaft 8 by e as shown in FIG. As shown in the figure, the pin diameter Dp of the eccentric pin portion 10 has a size such that the entire outer periphery falls within the cross-sectional contour determined by the diameter Ds of the main shaft portion 9 at this eccentric position. In this case, a part of the outer peripheral edge protruding outside the cross-sectional contour of the main shaft portion 9 is removed, and the eccentric pin portion 1 having the final shape is removed.
It is configured as 0.

That is, an oil groove 18 for guiding the lubricating oil to the sliding portion is formed in the main shaft portion 9 of the crankshaft 8 as shown in FIG. When the pin diameter Dp of the eccentric pin portion 10 is determined, the outer peripheral edge in the direction eccentric with respect to the axis of the main shaft portion 9 is set so as to slightly protrude out of the cross-sectional profile of the main shaft portion 9 (FIG. )) And the oil groove 18 described above in accordance with the protruding outer peripheral edge of the eccentric pin portion 10.
And the outer peripheral edge outside the cross-sectional profile is removed as a pin relief groove 19 by milling while following the oil groove 18. Thus, the shape shown in FIG. 1A is obtained. The eccentric pin portion 10 has the pin escape groove 19 so that the entire outer periphery of the eccentric pin portion 10 is inside the cross-sectional profile of the main shaft portion 9. In the drawing, reference numeral 20 denotes a contact surface with the swing link 12.

The thus configured crankshaft 8
In the above, only the pin diameter Dp of the eccentric pin 10 can be made larger while the diameter Ds of the main shaft 9 remains the same as the conventional one. During the operation of the compressor, the eccentric pin portion 10 in contact with the swing link 12 at the cross section 20 is subjected to the external force of the gas pressure generated in the process of compressing the refrigerant gas and the inertial force of the movable scroll 2. In a crankshaft having a thin eccentric pin portion, when this external force acts on the eccentric pin portion through the contact surface 20, a deflection that changes the alignment of the movable scroll occurs. The eccentric pin portion 10 can be configured to be thick and can prevent the eccentric pin portion 10 from bending due to an increase in the section modulus.

On the other hand, the eccentric pin portion 10 of the crankshaft 8 removes the outer peripheral edge protruding from the cross-sectional profile of the main shaft portion 9 and forms a pin escape groove 19 so that any portion crosses the main shaft portion 9. There is no protruding portion that enters the plane contour and hinders the assembly of the compressor, and the assembly can be performed smoothly as in the conventional case.

Further, since the pin relief groove 19 is formed simultaneously with the oil groove 18 on the outer surface of the main shaft portion 9, there is no need for special processing, no extra labor is required, and it is possible to manufacture the pin at extremely low cost. It is possible.

[0016]

As described above, according to the first aspect of the present invention, the eccentric pin portion has an eccentricity having a pin diameter determined so that only a part of the outer peripheral edge in the eccentric direction protrudes slightly from the cross-sectional profile of the main shaft portion. The eccentric pin can be made thicker while maintaining the main shaft diameter because the pin is configured.This effectively prevents the eccentric pin from flexing due to external force during compressor operation. It is.

According to the second aspect of the present invention, the outer peripheral edge of the eccentric pin portion outside the cross-sectional profile of the main shaft portion is removed simultaneously with the oil groove on the outer surface of the main shaft portion. It is not necessary to go through any special processing in the removal of, and it can be manufactured at extremely low cost.

[Brief description of the drawings]

FIG. 1A is an end view showing an eccentric pin portion of a crankshaft according to the present invention. (B) is sectional drawing of the same eccentric pin part.
(C) is a figure for demonstrating the method for determining the diameter dimension of an eccentric pin part.

FIG. 2 is a sectional view showing a scroll compressor according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed scroll 2 Movable scroll 4 Case 8 Crankshaft 9 Main shaft part 10 Eccentric pin part 18 Oil groove 19 Pin relief groove 20 Contact surface

 ──────────────────────────────────────────────────の Continuing on the front page (72) Kazuya Sato, 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Toshiyuki Ehara 2-5-2, Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd.

Claims (2)

[Claims] 1. A scroll compressor crankshaft having an eccentric pin portion eccentric with respect to an axis of a main shaft portion, wherein the eccentric pin portion has a direction eccentric with respect to an axis of the main shaft portion. Only a part of the outer peripheral edge has a pin diameter determined so as to slightly protrude from the cross-sectional profile of the main shaft portion, and the outer peripheral edge of the eccentric pin portion outside the cross-sectional profile is removed to obtain the final shape. A crankshaft for a scroll compressor, wherein the crankshaft is formed as an eccentric pin portion. 2. The apparatus according to claim 1, wherein said outer peripheral edge of said eccentric pin portion, which is outside the cross-sectional profile of said main shaft portion, is simultaneously removed along with an oil groove on an outer surface of said main shaft portion. 2. The crankshaft for a scroll compressor according to 1.