JPH11287101A - Oldham's ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an uneven contact load when an Oldham's ring is twisted and deformed by protruding a pair of first keys on a first horizontal surface of a ring main body, and protruding a pair of second keys on a second horizontal surface, in the Oldham's ring for preventing self-rotation of a movable scroll. SOLUTION: An oldham's ring 1 is composed of a ring main body 2 having a first horizontal surface 2a and a second horizontal surface, a pair of keys 3a, 3b protruded on the first horizontal surface 2a, and a pair of keys 4a, 4b protruded on the second horizontal surface. The keys 3a, 3b are engaged with a key groove arranged on a back surface of a movable scroll, and the keys 4a, 4b are engaged with a key groove arranged on a housing. Four seat surfaces are formed between keys 3a, 3b, 4a, 4b separated from each other within the range of 45 deg. in a rotational direction of the movable scroll from each key. It is thus possible to reduce an uneven contact load of each key in the case where the Oldham's ring 1 is twisted and deformed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Oldham ring for preventing rotation of a movable scroll in a scroll fluid machine.

[0002]

2. Description of the Related Art Conventionally, in a scroll fluid machine, an Oldham ring mounted under a movable scroll to prevent the movable scroll from rotating has been known. In FIG.
1 shows a scroll fluid machine 10 provided with an Oldham ring disclosed in Japanese Patent Publication No. 4-23081.

[0003] As shown in FIG.
0 includes an outer casing 18 in which a fixed scroll 14, a movable scroll 12, a housing 13,
The motor 16 and the crankshaft 17 are installed. The Oldham ring 11 is arranged between the movable scroll 12 and the housing 13. More specifically, the key 15 is press-fitted onto the projection 13 a of the housing 13, and the Oldham ring 11 is disposed on the key 15.

FIG. 6 shows an example of a sectional structure taken along the line VI-VI in FIG. As shown in FIG. 6, a key groove is formed in the Oldham ring 11, and a key 15 is fitted into the key groove. Oldham ring 11 is key 15
Are supported by the seating surfaces 19 on both sides of the vehicle. Since the keys 15 are attached at two places, the Oldham ring 11 is supported by the four seating surfaces 19.

[0005]

The Oldham ring 11
Has a ring shape as shown in FIG. 7, the keyway 9a of the Oldham ring 11 is fitted with the movable scroll 12,
The key groove 9b is fitted with the key 15 pressed into the projection 13a. Therefore, the rotation of the orbiting scroll 12 applies a force in the opposite direction to the side walls of the key grooves 9a and 9b, and when the force is large, the Oldham ring 11 undergoes torsional deformation.

[0006] When the Oldham ring 11 undergoes torsional deformation, the location where the amount of deformation is greatest is the keyway 9a,
They are not near 9b but at a distance from them. Therefore, even if the seating surface 19 is provided only near the keyway 9b as described above, the torsional deformation of the Oldham ring 11 cannot be effectively suppressed.

As a result, when a large force is applied to the Oldham ring 11 such as when the scroll fluid machine 10 is started or when a high load is applied, the Oldham ring 11 is torsionally deformed and the so-called one-sided load increases. I am concerned. This causes a problem such as an unstable operation of the orbiting scroll 12.

The present invention has been made to solve the above problems. An object of the present invention is to reduce a load per side when an Oldham ring is twisted.

[0009]

An Oldham ring according to the first aspect includes a ring body, first and second keys,
And a seating surface. The ring body has first and second horizontal surfaces in a front-to-back positional relationship. The first keys protrude from the first horizontal plane and face each other. The second key is disposed to face the direction orthogonal to the direction in which the first keys are arranged, and protrudes from the second horizontal plane. The first and second seats are adjacent
Are provided on a second horizontal plane located between the first and second keys. Here, the “seat surface” refers to a surface actively provided on the Oldham ring as a contact surface with a base material such as a housing.

When the Oldham ring is torsionally deformed, there is a portion where the amount of deformation is maximum at a position spaced from the first and second keys by a certain distance as described above. Therefore, by providing the seating surface at a position separated from both the first and second keys, the seating surface can be arranged immediately below the place where the amount of deformation of the Oldham ring is the largest. Thereby, when the Oldham ring is torsionally deformed, the Oldham ring can be reliably seated on the base material such as the housing, and the first or second
The load per key of the key can be reduced. Further, by separating the first and second keys from the seat surface, the first and second keys and the seat surface can be processed in different processes. Thereby, the resistance at the time of machining can be reduced as compared with the case of machining the key and the seat surface simultaneously. Furthermore, when the seating surface is selectively provided only immediately below the position where the amount of deformation is maximum, the processing area for forming the seating surface can be reduced. When the Oldham ring is formed by casting, a residual stress is generated in the Oldham ring. In this case, if the processing area is large, deformation due to the residual stress may increase. However, by selectively providing the bearing surface as described above, the processing area can be reduced, and the processing deformation of the Oldham ring can be suppressed.

An Oldham ring according to a second aspect is disposed between a movable scroll and a housing of a scroll fluid machine, wherein the first key is fitted to the movable scroll, and the second key is fitted to the housing. You. The seating surface is arranged within a range of 45 ° from the first or second key in the rotation direction of the movable scroll.

As described above, the first and second keys are fitted with separate members. Therefore, by rotating the orbiting scroll, forces in opposite directions are applied to the first and second keys. However, since the first and second keys are provided on the front and back of the Oldham ring, the first key is viewed from the outer periphery of the Oldham ring.
And the second key both receive a moment in the same direction.
As a result, the Oldham ring is deformed into a continuous waveform. Under such recognition, the inventor of the present application pays attention to the relationship between the rotation direction of the movable scroll and the location of the maximum deformation amount, and within a range of 45 ° in the rotation direction of the movable scroll from the first and second keys. It was found that there was a point with the maximum deformation. By arranging the seating surface within this range, the above-described effect can be obtained more reliably. Further, it is preferable to provide a seating surface on the surface of the housing at a position corresponding to the seating surface. However, by arranging the seating surface of the Oldham ring within the above range, the pair of seating surfaces can be moved to the keyway on the movable scroll side. Can be placed closer to Thereby, the refrigerant gas suction passage can be widened.

[0013] In the Oldham ring according to the third aspect, the seating surface is provided at four places. Thus, the Oldham ring can be supported at four points, and the load per side can be reduced more effectively.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view showing an Oldham ring 1 according to one embodiment of the present invention.

As shown in FIG. 1, the Oldham ring 1
First and second horizontal planes 2a, 2b in front-to-back positional relationship
Ring body 2 (not shown) and first horizontal surface 2
a pair of first keys 3a and 3b projecting from
A pair of second keys 4a and 4b protruding from the second horizontal surface 2b and facing each other are provided.

The first keys 3a and 3b are fitted into key grooves provided on the back of the movable scroll. Second key 4
The keys a and 4b are arranged in a direction perpendicular to the direction in which the first keys 3a and 3b are arranged, and are fitted into key grooves provided in the housing.

FIG. 2 shows a second housing disposed on the housing side.
2 is a plan view of the Oldham ring 1 as viewed from the horizontal plane 2b side. As shown in FIG. 2, four seating surfaces 5a to 5d are provided between the adjacent first and second keys 3a, 3b, 4a, 4b so as to be separated therefrom. More specifically, the seating surfaces 5a to 5d are formed within a range of 45 ° in the rotation direction 6 of the movable scroll from each key. By providing the seating surfaces 5a to 5d at the positions as described above, the load per key of each key can be reduced even when the Oldham ring 1 is twisted at the time of starting the scroll fluid machine or at a high load. . Hereinafter, the reason will be described in detail.

It is assumed that the orbiting scroll rotates according to arrow 6 as shown in FIG. As a result, the first keys 3a and 3b fitted to the orbiting scroll receive a clockwise moment when viewed from the outer peripheral side of the Oldham ring 1. On the other hand, a force in the direction opposite to the arrow 6 is applied from the housing to the second keys 4a and 4b fitted on the housing side. However, since the second keys 4a, 4b protrude in the opposite direction to the first keys 3a, 3b, as a result, the second keys 4a, 4b also rotate clockwise when viewed from the outer peripheral side of the Oldham ring 1. Moment will be added.

As described above, the first and second keys 3a, 3b,
When a moment in the same direction is applied to each of 4a and 4b, the Oldham ring 1 is deformed into a waveform as shown in FIG. More specifically, the ring main body 2 located between the keys is deformed into a continuous waveform. Therefore, there are two places where the maximum deformation amount exists between the keys, and both exist at positions shifted to any key side from the midpoint between the keys.

In view of the above results, the inventor of the present application has
We focused on the relationship between the location of the maximum amount of deformation on the housing side and the rotating direction of the movable scroll, and examined it. As a result, it has been found that there is a point of maximum deformation toward the housing within a range of 45 ° (more specifically, around 22.5 °) in the rotation direction of the movable scroll from each key. Then, the above-described seating surfaces 5a to 5d are arranged immediately below the location of the maximum deformation amount. Thereby, when the Oldham ring 1 is twisted and deformed, the four seating surfaces 5a to 5
d can be seated on the surface (seating surface) of the housing, so that the Oldham ring 1 can be prevented from being greatly twisted and deformed. As a result, the load on each key can be reduced, and the reliability of the Oldham ring 1 can be improved.

Here, the seat surfaces 5a to 5d will be described in more detail. The seat surfaces 5a to 5d are preferably provided so as to slightly protrude from the second horizontal surface 2b as shown in FIG. This makes it possible to more effectively reduce the above-mentioned load per side. Further, it is preferable that the seat surfaces 5a to 5d are formed so as to have a smooth and uniform height. As a result, when the Oldham ring 1 undergoes torsional deformation,
All four seat surfaces 5a to 5d are brought into contact with the housing,
The Oldham ring 1 is substantially evenly distributed between the four seat surfaces 5a to 5d.
Can be supported. This can also contribute to reducing the load per key of each key.

Further, as shown in FIG. 2, the seating surfaces 5a to 5d
The following effects can also be obtained by making the area of each key relatively small and away from each key.

The Oldham ring 1 is made of, for example, aluminum and may be manufactured by die casting. In this case, a residual stress exists in the Oldham ring 1, and the working deformation increases as the working area increases. At this time, by setting the seating surfaces 5a to 5d to have a small area as described above, it is possible to reduce machining deformation due to cutting for forming the seating surfaces 5a to 5d, and improve machining accuracy. Also, the seating surfaces 5a to 5d are separated from each key.
Is provided, each key and the bearing surfaces 5a to 5d can be cut in a separate step. Thereby, the cutting resistance can be reduced, and the processing accuracy can be improved.

Next, the structure of the housing in the scroll fluid machine when the Oldham ring 1 according to the present invention is employed will be described. FIG. 3 shows a housing 7 on which the Oldham ring 1 shown in FIG. 2 can be placed.

Referring to FIG. 3, key grooves 9a and 9b are provided in housing 7, and a second groove is provided in key grooves 9a and 9b.
Keys 4a and 4b are fitted respectively. In addition, on the surface of the housing 7, there are provided seating surfaces 7a to 7d which are respectively in contact with the seating surfaces 5a to 5d. By providing the seating surfaces 7a to 7d in this way, the seating surfaces 5a to 5d can be reliably seated.

The above-mentioned seating surfaces 7a to 7d are provided with seating surfaces 5a to 5d.
It is provided at a position corresponding to d. As a result, the seating surface 7
Since b and 7d are brought closer to the key groove on the movable scroll side, the gas suction passages 8a and 8b can be expanded. Thereby, the performance of the scroll fluid machine can be improved.

As described above, one embodiment of the present invention has been described. However, the embodiment disclosed this time is to be considered in all respects as illustrative and not restrictive. . The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[0028]

According to the Oldham ring according to the present invention, the load per one side of the first or second key when the Oldham ring is deformed can be reduced. Thereby, the reliability of the Oldham ring can be improved.
Further, the cutting resistance for forming the seat surface can be reduced, so that the processing accuracy can be improved. Further, the deformation of the Oldham ring can be reduced, which can also contribute to improving the processing accuracy.

According to the Oldham ring according to the second aspect, in addition to the above effects, the gas suction passage can be widened. Thereby, the performance of the scroll fluid machine can be improved.

According to the third aspect of the present invention, the load per side can be reduced more effectively, and the reliability of the Oldham ring can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an Oldham ring according to the present invention.

FIG. 2 is a plan view of the Oldham ring viewed from a housing side.

FIG. 3 is a plan view showing a housing.

FIG. 4 is a schematic view showing a state where the Oldham ring according to the present invention is deformed.

FIG. 5 is a sectional view showing a scroll fluid machine having a conventional Oldham ring.

FIG. 6 is a diagram showing an example of a cross-sectional structure along a line VI-VI in FIG. 5;

7A is a plan view of a conventional Oldham ring, and FIG. 7B is a cross-sectional view taken along line VIIb-VIIb in FIG. 7A.

[Explanation of symbols]

 1,11 Oldham ring 2 Ring body 2a First horizontal plane 2b Second horizontal plane 3a, 3b First key (movable scroll side) 4a, 4b Second key (housing side) 5a-5d Seat surface 6 Rotation direction 7, 13 Housing 7a to 7d, 19 Seating surface 8a, 8b Gas intake passage 9a, 9b Keyway

Claims (3)

[Claims] 1. A ring body (2) having first and second horizontal planes (2a, 2b) in a front-to-back positional relationship, and a pair of first and second projections protruding from and facing the first horizontal plane (2a). One key (3a, 3b) and a pair of the first keys (3a, 3b) are disposed so as to face each other in a direction orthogonal to the direction in which the first keys (3a, 3b) are arranged, and protrude from the second horizontal plane (2b). A second key (4a, 4b) and the first and second keys (3a) on the second horizontal plane (2b) located between the adjacent first and second keys (3a, 4a). , 4a), a seating surface (5a) provided at a distance from both of them. 2. The Oldham ring (1) is disposed between a movable scroll and a housing of a scroll fluid machine, the first keys (3a, 3b) are fitted with the movable scroll, and the second key is provided. (4a, 4b) is fitted to the housing, and the seat surface (5a) is connected to the first or second key (3
2. The Oldham ring according to claim 1, wherein the Oldham ring is arranged within a range of 45 ° from a, 4a) to a rotation direction (6) of the movable scroll. 3. The Oldham ring according to claim 1, wherein the seat surface is provided at four positions.