JPH0261381A - Oldham's coupling of scroll compressor - Google Patents

Abstract

PURPOSE:To obtain the structure of an Oldham's ring which possesses the superior durability for a lightweight ring made of aluminium by forming an R-part in a recessed form at the annular part of a root part where the key projection of an annular member and the annular part cross. CONSTITUTION:When an Oldham's coupling 8 is made of aluminium, each root part of a ring part and the key part projection parts 8a and 8b is formed into an R-form. Because of the R-form, the key-shaped projections 8a and 8b can be prevented from being broken. The R-shape is an R-form biting in the thickness direction of the ring, and can be formed through working or previously formed in the material preparing processes such as forging and casting. The area of the side surface of the key part of the Oldham's ring which acts as a sliding part can be formed to the vicinity of the ring part by forming the R-shape to a recessed form, the surface pressure of that part can be secured, and the mechanism free from the sliding characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an Oldham joint used in a rotation prevention mechanism of a scroll compressor, and particularly to an Oldham joint suitable for improving durability.

[Conventional technology]

Regarding the Oldham joint of a scroll compressor, the structure and operating principle are described in, for example, Japanese Patent Laid-Open No. 60-88226. has keys perpendicular to both surfaces of the annular member, and by fitting them together, it is possible to prevent the orbiting scroll from rotating. This Oldham ring is a strong member, and it is subjected to a load several times higher than normal due to the torque of the electric motor, especially at startup, so it was essential to have a strong design that would not cause damage. In addition, iron-based cast material such as FCD is used as the material.
The key part was made to protrude by machining from a material whose thickness was twice the height of the ring part and the center part, except for the four key parts on both sides.

[Problem to be solved by the invention]

In contrast to the above conventional technology, when using aluminum for the purpose of reducing the centrifugal load of the Oldham joint, the susceptibility to failure due to stress concentration on the part made of FCD becomes large in the case of aluminum material. No consideration is given to FCD
If the structure was made from aluminum, the key protrusion could break.

The purpose of the present invention is to reduce the weight of Oldham's joints to aluminum.
The purpose is to provide an Oldham ring structure with excellent durability.

[Means to solve the problem]

The above object is achieved by rounding the root of the thousand-protrusion portion of the aluminum Oldham joint, and by applying compressive residual stress to the root of the Φ-protrusion portion.

[Effect]

The Oldham joint has a total of 4 key protrusions, 2 on the orbiting scroll side and 2 on the frame side, and these are fitted into the key grooves of the orbiting scroll and frame, respectively, and are used to adjust the torque of the electric motor, gas load, etc. Centrifugal loads, etc. act on each part of the Oldham ring, causing stress, but conventional FC
Since the D material has low notch sensitivity, the maximum stress usually occurs at the center of the key on the orbiting scroll side and the key on the frame side, which are 90 degrees apart, that is, at 45 degrees. On the other hand, although smooth aluminum materials have the same strength as FCD materials,
The notch sensitivity is high, and the root of the key protrusion generates maximum stress compared to the 45-degree part.

Furthermore, it is expected that the base of the stepped portion provided other than the key protrusion will also be subjected to the same stress concentration.

Therefore, the durability of the aluminum Oldham joint can be improved by providing a concave rounded part at the root of the key protrusion to reduce notch sensitivity and increase the fatigue strength of the part.

Further, by forming the concave rounded portion, the lubricating oil holding capacity to be supplied to the key protrusion during sliding increases, and the sliding a% property is improved.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

As shown in FIG. 1, the scroll compressor has a compressor section in the upper part of the closed container 1, and a motor part (not shown) in the direction F, which are connected to each other via a crankshaft 7.

The compressor section is formed by interlocking the fixed scroll member 5 with a thinly wound zip 5b on the base plate 5a and the orbiting scroll member with the spiral wrap 4b upright on the base plate 4a, A suction port 5d is provided on the outer periphery of the fixed scroll member 5, and a discharge hole 5e is provided in the center.

The crankshaft 7 is supported by a bearing 6c in the center of the frame 6, and a protruding crank 7a of the crankshaft 7 is inserted into and engaged with the orbiting bearing 4c of the orbiting scroll member housing.

Now, Oldham's joint 8 as an autorotation prevention mechanism is a joint in which the orbiting scroll member 4 makes an orbital motion with respect to the fixed scroll member 5 without rotating on its axis, and the rear grooves 4C and 7 of the orbiting scroll member 40 base plate 4a Ram 6 pedestal 6
It is engaged between a.

Therefore, when the crankshaft 7 is rotated by the lower electric motor Vζ, the orbiting scroll member 4 performs an orbiting motion relative to the fixed scroll member 5 without turning due to the eccentric rotation of the crank 7a, and the refrigerant is sucked in from the suction port 5d. The gas is compressed, and the compressed gas is discharged from the discharge hole 5e.

Details of the anti-rotation mechanism members are shown in Figure iJ2 to Figure 4.
A keyway 6b provided in the pedestal 6a of the frame 6 and a keyway 4 provided in the back of the base plate 4a of the orbiting scroll member 40.
The four key-shaped protrusions ab of Oldham joint 8 are attached to C.
t88 engages and slides back and forth, thereby preventing the orbiting scroll member 4 from rotating.

Therefore, as shown in Fig. 5, gas load and centrifugal load act on the key-shaped protrusions 8a and 8bK (force F in the figure), but the starting torque of the electric motor acts directly on them especially during startup. There is.

Normally, the Oldham joint 8 is ring-shaped, so the position at 45'' in the figure (b) is the position where the maximum stress occurs.
Strength has sometimes been increased by increasing the cross-sectional area of the 45" part, but when making the Oldham joint 8 lightweight aluminum, the notch sensitivity is higher compared to iron Oldham joints, and the 45" part Also, the key-shaped protrusion 88*8b may be damaged.

Therefore, as shown in FIG. 6, in order to make the Oldham's joint aluminium, the base of the joint and the key-shaped protrusion are rounded. This shape can prevent the key-shaped protrusions 8a+8b from being damaged. The radius shape is a 1-rule (so-called concave radius) that is dug into the ring in the thickness direction as shown in the figure.

Further, the rounded shape can be formed by machining, or can be formed in advance in the process of producing a material such as forging or casting.

By making the rounded shape concave, the area of the side surface of the key part of Oldham's ring, which acts as a sliding part, can be formed close to the ring part, ensuring blood pressure in the part, and sliding! ll&! It is possible to provide a mechanism that does not impair the flexibility. This is even more effective because the key 11IIIi can be made deeper than the ring portion by widening the width of the rounded surface as in the embodiment shown in FIG.

Furthermore, if two grooves are provided on the rounded surface as in the embodiment shown in FIG. 1O, it is only necessary to process the key side surface and the upper surface of the key, thereby simplifying the processing. Furthermore, since it can be formed by forging, it is convenient for mass production, as machining of the relevant part can be omitted.

In addition, in order to reduce notch sensitivity, it is also preferable to apply compressive residual stress to the root of the I″t% gee-like protrusion, and this can be achieved, for example, by applying shot or t throat blasting to the part. Ciotto or sandblasting was also effective in improving the sliding properties of the area, and the roughening of the surface made it possible to maintain a lubricating oil film.

It goes without saying that by combining the two, reliability can be improved.

Furthermore, electrical discharge machining is sometimes used as a method for machining concave radiuses. In this case, as in the example shown in FIG. 7, it is sufficient if the R shape into which the ring part and the key part are sunk is the surface of the sliding area force intensifying port.

On the other hand, by creating a concave radius, the concave radius becomes a pocket that retains and supplies lubricating oil during sliding between the key protrusion and the keyway of the Oldham ring. Effective in preventing galling and seizure caused by running out of oil.

Furthermore, during operation, it becomes a passage for V'i lubricating oil, making it easier to supply lubricating oil to the sliding parts, which is effective in improving the sliding life.

Modifications of the rounded portion are shown in FIGS. 7 to 10.

〔Effect of the invention〕

According to the present invention, when making a lightweight aluminum Oldham joint, there is a method of making the part corresponding to 45° thicker, but due to the evaluation of the notch sensitivity of aluminum material, the 45° part is not made thicker. This can be achieved by forming the base of the key-like protrusion into a concave rounded shape, so there is no unnecessary increase in weight or processing man-hours, and there is an effect of providing an economically excellent Oldham joint.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing the pressure mechanism of the scroll compressor, Fig. 2 is a sectional view of the orbiting scroll member which is a component of the Oldham joint, Fig. 8 is a top view of the frame, and Fig. 4 is FIG. 5 is a perspective view of the Oldham joint, FIG. 5 is a top view of the Oldham joint, and FIG. 6 is a front view of the Oldham joint which is an embodiment of the present invention. FIG. 7 to FIG. 1θ are enlarged partial views of Oldham's joints which are other embodiments. 1... Airtight container 4... Orbiting scroll member 4a
...Orbiting scroll base plate 4b...Orbiting scroll lab plate 5...Fixed scroll member 6...
Frame 6a...Frame stand flit 6b
...Frame keyway 7...Crankshaft 8.
...Oldham g hand sa...Oldham key 8b
...Oldham Quay Judge 2 Zuka 10

Claims (5)

[Claims] 1. A fixed scroll member and an orbiting scroll member having a spiral wrap standing upright on the base plate are engaged with each other and held in a frame, and the rear face of the base plate of the orbiting scroll is engaged with the crankshaft, and the back face of the base plate of the orbiting scroll and the frame base are engaged with each other. An Oldham joint is provided between the annular member to prevent rotation of the orbiting scroll member, and this Oldham joint is provided with a key-shaped protrusion in the diametrical direction on one side of the annular member, and a key-shaped protrusion in the direction perpendicular to the protrusion on the other side of the annular member. In a device having a structure in which a key-shaped protrusion is provided on the annular member, and the protrusion on both sides engages with a key groove provided on the back of the base plate of the orbiting scroll member and the base of the frame, the base where the key-shaped protrusion of the annular member and the annular part intersect An Oldham joint for a scroll compressor, characterized in that a concave rounded portion is formed in an annular portion. 2. Claim 1 characterized in that a compressive residual stress is applied to a portion of the annular member where the key-shaped protrusion and the annular portion intersect.
Oldham coupling for the scroll compressor described. 3. The Oldham joint for a scroll compressor according to claim 1, wherein the annular member of the Oldham joint is made of aluminum. 4. The annular member of the Oldham joint is made of aluminum and has a concave radius.
The Oldham joint for a scroll compressor according to claim 1, wherein the Oldham joint has an R shape as formed. 5. 2. The Oldham joint for a scroll compressor according to claim 1, wherein the annular member of the Oldham joint is made of aluminum and formed by forging.