JP2804928B2 - Scroll fluid machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll fluid machine suitable for an air conditioner, a refrigerating compressor, an air compressor, and a pump expander, and more particularly, to preventing rotation of a orbiting scroll. It relates to the improvement of the mechanism. 2. Description of the Related Art Generally, as shown in FIG. 5, the structure of a scroll fluid machine is mainly composed of a fixed scroll 1 and an end plate 2a formed on a spiral wrap 1b standing upright on an end plate 1a. The orbiting scroll 2 is formed by forming an upright spiral wrap 2b, a rotation preventing mechanism, a frame 3, and a driving mechanism. The fixed scroll 1 and the orbiting scroll 2 are engaged with each other, and the fixed scroll is fixed to the frame 3. The orbiting scroll 2 is prevented from rotating by rotating the crankshaft 4 by fitting a crank pin 4a of a crankshaft 4 supported by a bearing on a frame 3 as a drive mechanism to a bearing boss 2c on the back of the orbiting scroll 2. The orbital movement is made relative to the fixed scroll 1 while being prevented by a mechanism. Reference numerals 6 and 7 denote a rotor and a stator of a motor for driving the crankshaft 4 to rotate, and 8 denotes a chamber. In the case of the operation as a compressor, when the crankshaft 4 is rotated by the motor and the orbiting scroll 2 is orbited as described above, the gas entering from the suction pipe 9 causes the compression chamber 5a formed between the wraps of both scrolls. , 5b, and is discharged from the central discharge port 14 of the fixed scroll 1 and discharged outside the machine from the discharge interval 10 through the motor chamber of the chamber 8. 40 is a balance weight attached to the crankshaft 4. In the above configuration, the anti-rotation mechanism is for preventing the orbiting scroll 2 from rotating while preventing the orbiting scroll 2 from rotating, and the conventional structure is as shown in FIGS. The key 13 is press-fitted and fixed in a straight line on the back surface of the circular Oldham ring 11, and the key 13 is slid along the circular Oldham ring 11 at a position opposite to the key 13 so that the key 13 is slid along the groove. A similar groove 11b is provided at a position orthogonal to the above, a protrusion is provided on the frame 3 at a position opposite to the groove 11b, and a key 12 is press-fitted and fixed onto the protrusion, and the key 12 is slid into the groove 11b. The Oldham ring 11 is configured to be slidable in the directions of the grooves 11a and 11b so as to allow the orbiting scroll 2 to rotate while preventing its rotation. As another conventional example, instead of providing a groove in a circular Oldham ring, an Oldham ring that stands upright from the surface of the Oldham ring is provided (ie, 11a, FIG.
A portion indicated by 11a or 11b, 11b is not a groove but an upright key), and there is also a structure in which a groove in which the key fits is provided in a revolving scroll or a frame projection as a counterpart member. [0005] As described above, the Oldham ring in the prior art has a circular shape, and the Oldham ring has not been reduced in size and weight. There is a problem that the vibration becomes large, and this also hinders the miniaturization of the whole crawl fluid machine. An object of the present invention is to reduce the size and weight of an Oldham ring, thereby reducing the occurrence of vibration,
Another object is to reduce the size of the scroll fluid machine. The object of the present invention is to provide a fixed scroll having an end plate and a spiral wrap standing upright on the end plate; and a frame for fixing a peripheral portion of the fixed scroll end plate;
An orbiting scroll having an end plate and a spiral wrap upright on the end plate and having the wraps inside each other and meshing with the fixed scroll and surrounded by the fixed scroll and the frame; and between the orbiting scroll end plate and the frame. And the Oldham ring arranged parallel to the orbiting scroll end plate, and the Oldham ring in the first radial direction only for the frame and for the orbiting scroll in a first direction perpendicular to the first radial direction. 2. An Oldham ring-frame engaging means and an Oldham ring-rotating scroll end plate engaging means for respectively engaging the Oldham ring with the frame and the orbiting scroll end plate so as to be movable only in the radial direction. An anti-rotation mechanism that allows the orbiting scroll to move relative to the fixed scroll while preventing the orbiting scroll from rotating; A drive mechanism for pivoting movement of the roll relative to the fixed scroll; in the scroll fluid mechanism wherein the Oldham ring has two axes of symmetry of phase quadrature and of them one symmetry axis (minor axis)
The ring diameter at is one other symmetric axis direction (long axis direction)
And the other is one of the shorter diameter direction and the longer diameter direction of which coincides with the first radial direction and the second radial direction, respectively. This is achieved by being arranged so that The oval Oldham ring according to the present invention is smaller and lighter than the conventional circular Oldham ring having the diameter of the major axis of the oval Oldham ring according to the present invention. Compact and lightweight. When the elliptical Oldham ring is provided with engagement means for preventing rotation which protrudes outward in the direction of the axis of symmetry, the load acting on the engagement means for preventing rotation of the orbiting scroll is changed in two orthogonal directions. Can be easily or substantially equalized. FIG. 2 is a longitudinal sectional side view of a main part of a scroll fluid machine incorporating an Oldham ring according to a first embodiment of the present invention.
FIG. 1 shows a plan view of the Oldham ring and the frame as viewed from above. The structure of the other parts of the scroll fluid machine is substantially the same as that of FIG. In the present embodiment, the oval Oldham ring 15 has a pair of keys 15a projecting in opposite directions in the minor diameter direction.
5 has a pair of keys (or key grooves) 15b in the major axis direction. A pair of keys 15a in the minor diameter direction is formed by a pair of corresponding key grooves 3b formed on the inner protrusion 3a in the frame 3.
Slidably engaged with the end plate 2a of the orbiting scroll 2 on the other hand.
Pair of corresponding keyways (or keys) on the underside of the
It is slidably engaged with 2d. The key (or key groove) 2d provided on the orbiting scroll 2a is not shown in FIG. In the above embodiment, the Oldham ring 1
5 moves with the swiveling crawl bearing boss 2c in the ring 15 for the movement in the short diameter direction, so that the inner diameter of the Oldham ring 15 in the short diameter direction is changed to the bearing boss 2c.
Can be made slightly smaller than the outer diameter of. In the second embodiment shown in FIGS. 3 and 4, the oval Oldham ring 15 has a pair of keys 15 c protruding in opposite directions in the minor axis direction.
On the surface of the ring 15, there is provided a pair of keys 15d in the major axis direction. The pair of keys 15c is the orbiting scroll end plate 2a.
Is slidably engaged with a corresponding pair of key grooves 2d 'provided on the lower surface of the frame 3, and the other pair of keys 15d is
Are slidably engaged with a corresponding pair of key grooves 3b 'formed on the inner protrusion of the key. In the second embodiment, relative movement occurs between the Oldham ring 15 and the orbiting scroll bearing boss 2c in the Oldham ring 15 in the short diameter direction of the Oldham ring 15 in accordance with the orbital radius of the orbiting scroll. In order not to hinder, the minor dimension of the Oldham ring 15 needs to be larger than that of the first embodiment. As in the first embodiment, the frame 3
If the key on the Oldham ring that slidingly engages with the keyway on the side is a key that protrudes radially from the Oldham ring and is located in the plane of the Oldham ring when viewed from the side, FIG. As shown in the figure, the keyway on the frame side and the Oldham ring 15 are substantially in a straight line when viewed from the side, so that the distance between the orbiting scroll end plate 2a and the keyway on the frame 3 can be reduced. And the distance between the orbiting scroll and the balance weight 40 can be reduced, so that there is an advantage that the function of the balance weight can be improved and the size and weight can be reduced. According to the scroll fluid machine of the present invention, the Oldham ring is formed into an elliptical shape having a symmetric axis in two orthogonal directions and a major axis and a minor axis in the direction of the target axis. Compared to using Oldham ring,
It is possible to reduce the size and weight of the Oldham ring, and as a result, it is possible to reduce the generation of vibration and, consequently, to contribute to the downsizing of the scroll fluid machine. In particular, when the oblong Oldham ring is provided with engagement means for preventing rotation protruding in the short diameter direction, the load on the engagement means in both orthogonal directions is substantially equalized, and the Oldham ring is reduced in size and weight. Can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view of an Oldham ring and a frame according to a first embodiment of the present invention. FIG. 2 is a sectional view of a main part of the scroll fluid machine according to the first embodiment. FIG. 3 is a top view of an Oldham ring and a frame according to a second embodiment of the present invention. FIG. 4 is a longitudinal sectional view of a main part of the scroll fluid machine according to the second embodiment. FIG. 5 is a longitudinal sectional view of a conventional scroll fluid machine. FIG. 6 is a bottom view of the orbiting scroll in FIG. 5; FIG. 7 is a plan view of the Oldham ring in FIG. 5; [Description of Signs] 1 ... fixed scroll, 2 ... orbiting scroll, 2a ...
... orbiting scroll end plate, 3 ... frame, 4 ... crankshaft, 15 ... Oldham ring, 40 ... balance weight

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F04C 18/02 311

Claims (1)

(57) [Claims] A fixed scroll having an end plate and a spiral wrap upright thereon; a frame for fixing the periphery of the fixed scroll end plate; and a fixed scroll having an end plate and a spiral wrap upright on the end plate, with the wraps inside each other. A revolving scroll disposed between the fixed scroll and the frame; and an Oldham ring disposed between the revolving scroll end plate and the frame, and the Oldham ring in a first radial direction with respect to the frame. Oldham ring which engages the Oldham ring with the frame and the orbiting scroll end plate so as to be movable only in the second radial direction perpendicular to the first radial direction with respect to the orbiting scroll. Having inter-frame engagement means and Oldham ring-orbiting scroll end plate engagement means,
In a scroll fluid machine, comprising: a rotation preventing mechanism for allowing the orbiting scroll to rotate with respect to the fixed scroll while preventing the orbiting scroll from rotating; and a drive mechanism for causing the orbiting scroll to orbit with respect to the fixed scroll, the Oldham ring is orthogonal to the crossing. are two has an axis of symmetry and of which the one axis of symmetry direction shorter oval shaped Oldham ring than the ring diameter at the ring diameter at the (minor axis) of the other one symmetry axis (major axis direction), The elliptical Oldham ring is arranged such that one and the other of its short diameter direction and long diameter direction coincide with the first radial direction and the second radial direction, respectively.
Adjust the length of the dam ring in the minor axis direction to that of the orbiting scroll.
The elliptical shape is larger than the outer diameter of the engagement portion of the drive mechanism.
The length of the long axis direction of the dam ring is
A scroll fluid machine having a diameter smaller than an outer diameter of a material .