JPH10103260A - Scroll fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To equalize bearing pressure that a chip seal receives by fixing a turn scroll fitted in an eccentric shaft part of an eccentric drive shaft in such a manner that a clearance at a tip of a scroll tooth becomes uniform on every contact face and fitting and attaching the chip seal. SOLUTION: Fixed scrolls 3, 4 are constituted by an angular ball bearing 13 in such a manner that they do not move in the axial direction between an eccentric drive shaft 1 and it. Furthermore, a turn scroll 2 is fixed by the angular ball bearing 13 and a bearing lock ring 14 at the dimension at which a clearance 7 is held on two contact faces between the fixed scrolls 3 and 4 without the travel in the axial direction on an eccentric shaft part 1a. Consequently, the turn scroll 2 turns without moving in the axial direction on the shaft, and the clearance 7 is not changed for a long time of turn. As a result, a chip seal 6 fitted in tips of a turn scroll tooth 5 and a fixed scroll tooth holds set bearing pressure at any turn position to guarantee the normal operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eccentric drive shaft for a scroll fluid machine when a rotary scroll is constructed.

[0002]

2. Description of the Related Art The orbiting structure of an orbiting scroll in a scroll fluid machine mainly including an orbiting scroll, a fixed scroll, and an eccentric drive shaft is such that the clearance of the tip of the scroll teeth is uniform with respect to the fixed scroll. Not configured. Therefore, the orbiting scroll moves in the axial direction, and the orbiting scroll is eccentrically located at the eccentric shaft portion due to the processing accuracy of each part and the assembling technique.

[0003]

In a conventional scroll fluid machine, the orbiting structure of the orbiting scroll is such that an eccentric shaft portion of an eccentric drive shaft is rotatably fitted into an orbiting scroll boss portion.
The fixed scroll is the rotation axis of the eccentric drive shaft, is fitted into the rotation shaft, and the scroll teeth are configured to overlap each other,
Further, a tip seal is fitted to the tip of each scroll tooth, and the tip seal is fixedly engaged with the inner surface of the end plate of the orbiting scroll so as to orbitally slide, so as to orbit while maintaining airtightness.

However, in this configuration, since the orbiting scroll is not axially fixed to the eccentric shaft portion of the eccentric drive shaft, there are two fixed scroll teeth and the orbiting scroll teeth on the eccentric shaft portion. In the axial direction within the axial clearance,
It will be set at a free position. That is, in order for the tip seal to operate normally, it is necessary that the clearance between the orbiting scroll teeth and the inner surface of the fixed scroll head and the clearance between the orbiting scroll head and the fixed scroll teeth be uniform. But in the orbiting scroll,
Since the positioning can be freely performed on the eccentric shaft portion, it is structurally impossible to position the axial center of the orbiting scroll at the center of the axial space set by the fixed scroll.

Accordingly, if the orbiting scroll is assembled to the right side on the eccentric shaft portion, for example, in the case of a twin type scroll, the clearance at the tip of the scroll tooth on the right side from the center becomes small, and the tip seal receives abnormal surface pressure. , Causing premature wear. On the other side, on the left side of the center, the tip clearance of the scroll teeth is large, and the tip seal has a weak surface pressure, causing leakage over the entire scroll area, making it impossible to maintain the required pressure. In the single type scroll, the gap becomes large or small due to the uneven distribution of the orbiting scroll, and the same phenomenon as described above occurs. Further, the orbiting scroll is fitted to the eccentric shaft portion via a plurality of bearings, and the oil seal is fitted thereon. Therefore, the shaft has a very large shaft fitting force and acts on the shaft. Further, since the surface pressure of the tip seal has a spring property weaker than these shaft fitting forces, the phenomenon that the orbiting scroll is moved on the axis by the surface pressure of the tip seal hardly occurs. Therefore, it can be said that the orbiting scroll mounted eccentrically on the eccentric shaft cannot operate to adjust the clearance of the tip of the scroll teeth by itself. An object of the present invention is to fix the orbiting scroll to the eccentric shaft portion of the eccentric drive shaft and the center in the axial direction, excluding the various adverse effects as described above.

[0006]

The rotary shaft of the fixed scroll and the eccentric drive shaft are fixed by an axial fixed type bearing, and further,
An eccentric shaft portion of the eccentric drive shaft to be fitted into the orbiting scroll is also fixed by an axially fixed bearing and does not move in the axial direction.

[0007]

As described in the means for solving the above problems, an axially fixed bearing is disposed on the rotating shaft portion of the eccentric drive shaft and the eccentric shaft portion to maintain a uniform clearance at the tip of the scroll teeth. The axial movement between the scrolls and the eccentric drive shaft is eliminated, the surface pressure of the tip seal is made uniform, and a smooth turning motion can be performed while maintaining a state of exerting a sufficient effect on the compression action. Like that.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A twin scroll fluid machine shown in FIGS. 1 and 2 will be described as an embodiment. FIG. 1 is an overall configuration diagram of a conventional twin-type scroll fluid machine.
The clearance between the scroll teeth of the three and four fixed scrolls is
It is extremely difficult to make the left and right clearances uniform. That is, the two orbiting scrolls can freely move in the axial direction on the 1a eccentric shaft portion of the 1 eccentric drive shaft. FIG. 2 shows an embodiment of the invention according to claim 1 of the present invention, wherein 1 is an eccentric drive shaft, 1a is an eccentric shaft portion, 1b, 1
c denotes a rotary shaft portion, 1a an eccentric shaft portion is a 10 needle bearing, 8 double row angular ball bearings, and 2
It fits into the orbiting scroll boss. The fixed scrolls 3 and 4 consist of 13 double-row angular ball bearings and 1
It is fixed to the 1c rotary shaft by four bearing retaining rings, and does not move in the axial direction with one eccentric drive shaft. The above-mentioned two orbiting scroll is an 8 angular ball bearing fitted in the boss portion,
9, 9 'bearing retaining ring, 15 bearing collar, the boss portion of the two orbiting scroll, axial center so that it is located at the axial center of the 1a eccentric shaft portion, fixed on 1a eccentric shaft without movement, configuration I do. Numeral 7 indicates the clearance between the tip of each scroll tooth and the facing head plate, and the clearance is maintained so as to be uniform at all set positions. FIG. 3 shows an overall configuration diagram of a single type scroll fluid machine in which an eccentric drive shaft is fitted.

Next, the operation will be described. Due to the rotation of the eccentric drive shaft about the rotation axis, the orbiting scroll performs a revolving orbiting motion. At this time, the fixed scrolls 3 and 4 are constituted by 13 angular ball bearings without any axial movement with respect to one eccentric drive shaft. Further, the two orbiting scrolls have a clearance of 7 between the fixed scrolls 3 and 4. With the contact surface and the held dimensions, 1a without any axial movement on the eccentric shaft
It is fixed by 3 angular ball bearings and 14 bearing retaining rings. Therefore, the two orbiting scrolls orbit without moving in the axial direction on the shaft, and the clearance 7 is driven without changing over a long period of the orbiting. Therefore, the six-turn seals fitted to the tips of the five orbiting scroll teeth and the fixed scroll teeth of the 5a hold the set surface pressure at any of the turning positions, and normal operation is guaranteed. Although the embodiment is a twin-type scroll fluid machine, the orbiting scroll width, the eccentric shaft portion of the eccentric drive shaft is inserted into the whole, and it can be sufficiently applied to a single-type scroll fluid machine having a configuration of orbiting motion. Of course.

[0010]

In the scroll fluid machine according to the present invention, when the orbiting scroll orbits in the orbiting space set by the fixed scroll, the orbiting scroll fitted into the eccentric shaft portion of the eccentric drive shaft has scroll teeth. Since the tip clearance is fixed so as to be uniform on any contact surface and the tip seal is fitted, the surface pressure received by the tip seal can be equalized. Therefore, the orbiting scroll moves freely on the eccentric shaft part, and the tip clearance of the scroll teeth expands or contracts freely. There is no shortage of service life, no reduction in compression ratio due to leakage between the compression chambers caused by insufficient surface pressure, and insufficient maximum pressure and vacuum. Further, since the present invention does not move in the axial direction, there is an effective feature that the turning operability is stabilized, and the present invention has a great effect.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a conventional twin-type scroll fluid machine.

FIG. 2 is a vertical cross-sectional configuration diagram of each scroll and an eccentric drive shaft of a twin-type scroll fluid machine according to the present invention.

FIG. 3 is an overall configuration diagram of a single scroll fluid machine according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Eccentric drive shaft 1a ... Eccentric shaft part 1b, 1c ... Rotating shaft part 2 ... Orbiting scroll 3 ... Fixed scroll 4 ... Fixed scroll or casing 5 ... Orbiting scroll tooth 5a ... Fixed scroll tooth 6 … Tip seal 7… Clearance between the end of the scroll teeth and the facing mirror plate 8… Angular ball bearing (eccentric shaft) 9, 9 '…
Bearing retaining ring (eccentric shaft) 10 Needle bearing (eccentric shaft) 11, 12
... oil seal (eccentric shaft) 13 ... angular ball bearing (rotary shaft) 14 ... bearing retaining ring (rotary shaft) 15 ... bearing collar S ... eccentric amount

Claims (1)

[Claims] An orbiting scroll and an eccentric drive shaft, wherein the orbiting scroll is configured to orbit and swing, and both fixed and orbiting scroll end plates are provided with scroll teeth in the axial direction; In a scroll fluid machine that constitutes a wrap portion and compresses a compression chamber toward the center from an outer periphery, a fixed axial bearing is fitted into a rotation shaft portion of an eccentric drive shaft, and the eccentric drive shaft is fixed to the fixed scroll. Is configured not to move in the axial direction, and by fixing an axially fixed type bearing fitted to the eccentric shaft portion of the eccentric drive shaft to the orbiting scroll and the eccentric shaft portion, the orbiting scroll moves relative to the eccentric drive shaft. A scroll fluid machine, wherein the scroll fluid machine does not move in the axial direction.