JPH07208349A - Scroll lubricated fluid machine - Google Patents

Abstract

PURPOSE:To provide a scroll unlubricated fluid machine of high performance and low noises by scattering a sliding load to be applied to keys of an Oldham's joint to a plurality of projections. CONSTITUTION:Provided are a frame 5, a scroll fixed to the frame 5, an oscillating scroll 7 which has a spiral lap 12 stood on one surface of a mirror plate 1, and an Oldham's joint 33 which makes the oscillating scroll revolute on a circular orbit in respect to the fixed scroll. Gas such as air is compressed by gradually contracting a compression space formed between the scrolls from an outside to an inside. The Oldham's joint has a plurality of keys 40, 41 on the respective surfaces on the side of the oscillating scroll 7 and on the side of a frame 5. The keys are composed of a plurality of projections 42, 43. A plurality of recessions 44, 46 and key grooves 45, 47 are formed on the surfaces on the sides of both oscillating scroll 7 and frame 5 correspondingly to the keys 42, 43.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type oilless type fluid machine having a drive device for transmitting the rotational force of an electric element to an orbiting scroll.

[0002]

2. Description of the Related Art A conventional scroll type oil-free fluid machine,
In particular, the compressor is provided with a scroll compression element and an electric element, for example, as disclosed in Japanese Patent Laid-Open No. 262186/1987, and the scroll compression element is fixed to the frame having a bearing in the center. A fixed scroll having an end plate and a spiral wrap erected on the end plate, and an end plate, a spiral wrap erected on one surface of the end plate, and a boss erected on the other surface. An orbiting scroll is provided, and an Oldham coupling that revolves the orbiting scroll on a circular orbit so that the orbiting scroll does not rotate with respect to the fixed scroll, and the compression space formed between the two scrolls faces from the outside to the inside. It is configured to gradually reduce and compress gas such as air.

The Oldham coupling has a plurality of keys on the orbiting scroll side surface and the frame side surface, and each key is formed by a single convex portion, while On the scroll side surface and the frame side surface, a key groove formed of a single concave portion is formed corresponding to the key formed of the single convex portion.

In the scroll type oil-free fluid machine of this structure, since it is oil-free, the surface where the fixed scroll and the orbiting scroll are in sliding contact is subject to gas leakage due to wear or abrasion. Careful consideration must be given to the materials and processing accuracy of both scrolls and Oldham's joints.

[0005]

However, according to the above structure, the plurality of keys of the Oldham coupling formed on the surface on the orbiting scroll side and the surface on the frame side have a single convex portion at each position. The sliding load per unit area applied to the side surface of the convex portion (sliding load for revolving the orbiting scroll so that it does not rotate) is large, and the material of the Oldham coupling has a high hardness. In addition to the need for various materials, the increase in the sliding load promotes wear and wear due to sliding, and the amount of advance of the orbiting scroll (to the extent that it advances angularly in the rotational direction)
Becomes larger, the wrap of the orbiting scroll bites into the wrap of the fixed scroll, and abnormal contact between the wraps causes abnormal wear of both wraps, which causes abrasion powder to scatter in the compression space, reducing the performance of the compressor. There was a problem of causing abnormal noise.

The present invention solves the above problems.
The sliding load applied to each key of the Oldham coupling is reduced by distributing it to multiple convex parts, and the advance amount of the orbiting scroll is maintained well, and abnormal wear and abrasion powder are generated due to the bite of the scroll of the volume scroll. It is an object of the present invention to provide a scroll-type oil-free fluid machine with high performance and low noise.

[0007]

According to a first aspect of the present invention, there is provided a scroll compression element and an electric element, and the scroll compression element has a frame having a bearing in the center, an end plate fixed to the frame, and an end plate. A fixed scroll having a spiral wrap standing on the end plate, an orbiting scroll having a end plate, a spiral wrap standing on one surface of the end plate, and a boss standing on the other surface. And an Oldham coupling that revolves the orbiting scroll on a circular orbit so as not to rotate with respect to the fixed scroll,
In a scroll type oil-free fluid machine that compresses a gas such as air by gradually reducing the compression space formed between the scrolls from the outside to the inside, the Oldham coupling is provided on the orbiting scroll side. The surface and the surface on the frame side have a plurality of keys or key grooves, and each key or key groove is composed of a plurality of protrusions or recesses, while the surface on the orbiting scroll side and the frame side. The surface has a key groove or a key formed of a plurality of recesses or protrusions corresponding to the key or the key groove of the plurality of protrusions or recesses.

According to a second aspect of the present invention, the Oldham coupling of the first aspect is formed of a synthetic resin material.

[0009]

The present invention is constructed as described above,
Since the plurality of keys or keyways of the Oldham coupling are formed by the plurality of protrusions or recesses at each location, the sliding load per unit area applied to the side surface of each protrusion or recess (the orbiting scroll does not rotate) PV which is the standard for material selection.
It is possible to use a material having a low value. Therefore, it is possible to use an inexpensive material that is not so high in hardness as the material of the Oldham coupling, which can reduce the manufacturing cost, and the reduction of the sliding load reduces wear and abrasion due to sliding, thereby promoting the progress of the orbiting scroll. Maintains a good angular amount (the degree to which it advances angularly in the direction of rotation) and keeps the contact between the orbiting scroll wrap and the fixed scroll wrap as set, improving the performance of the compressor and causing abnormalities. It is possible to prevent the generation of noise.

Further, by using the synthetic resin material, not only the reduction of the manufacturing cost can be further promoted, but also the weight and durability of the compressor can be further improved.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings. Reference numeral 1 denotes a scroll air compressor, which is composed of an upper scroll compression element 2 and a lower electric element 3. The scroll compression element 2 is composed of a frame 5 having a main bearing 4 in the center, a fixed scroll 6 fixed to the frame, and an orbiting scroll 7 sandwiched between the fixed scroll and the frame 5. .

The fixed scroll 6 has a disk-shaped end plate 8, an annular wall 9 projecting from the peripheral edge of one end of the end plate, and a spiral wrap 1 erected on the end plate 8 surrounded by the annular wall.
It is composed of 0 and. The fixed scroll 6 has the annular wall 9 and the wrap 10 protruding downward.

The orbiting scroll 7 has a disk-shaped end plate 11,
A spiral wrap 12 erected on one surface of this end plate
And the boss portion 13 protruding in the center of the other surface of the end plate 11.
It consists of and. The orbiting scroll 7 has the wrap 12 projecting upward.

The fixed scroll 6 and the orbiting scroll 7 are formed so that the wraps 10 and 12 face each other and engage with each other to form a plurality of compression spaces 14. The electric element 3 includes a motor cover 15 fixed to the frame 5 and a stator 16 fixed in the motor cover.
And a rotor 17 arranged inside the stator and a rotary shaft 18 inserted in the center of the rotor. The motor cover 15 has an auxiliary bearing 1 that supports a rotating shaft.
9 is provided.

A ball bearing 24 fitted to the step portion 20 of the rotary shaft 18 is attached to the main bearing 4. 25
Is a drive device that transmits the rotational force of the electric element 3 to the orbiting scroll 7. The drive device balances the unbalanced force of the orbiting scroll 7 and the boss hole of the boss portion 13 of the orbiting scroll. An eccentric bush 28 which is inserted into the eccentric bush for orbiting the orbiting scroll 7, and a pin 29 for positioning the eccentric bush and the balance weight.
The eccentric bush 28 is fixed to the rotary shaft 18 with a bolt 30.

The fixed scroll 6 has a suction hole 31 communicating with the outer compression space 14 in the annular wall 9 and a discharge hole 32 communicating with the compression space 14 in the center of the end plate 8.

Here, the end plate 11 of the orbiting scroll 7 is described.
An annular groove 22 is formed in the abutting surface 21 of the fixed scroll 6 that faces the fixed scroll 6, and a seamless annular seal member 23 made of a synthetic resin material or the like is formed in the annular groove 22.
An elastic body 27 made of a rubber material (which may be a leaf spring) that presses the seal member toward the orbiting scroll 7 is housed.

Reference numeral 33 is an Oldham coupling made of a synthetic resin material interposed between the orbiting scroll 7 and the frame 5. The Oldham coupling 33 has a plurality of keys 40, 41 on the surface on the side of the orbiting scroll 7 and the surface on the side of the frame 5.
And each of these keys 40, 41 has a plurality of protrusions 42, 43.
It consists of On the other hand, on the lower surface of the orbiting scroll, a key groove 45 formed of a plurality of concave portions 44 corresponding to the key 40 formed of the plurality of convex portions 42 is formed.
Further, on the lower surface on the frame 5 side, a key groove 47 composed of a plurality of recesses 46 is formed corresponding to the key 41 composed of the plurality of projections 43.

When the electric element 3 is rotated in the scroll type air compressor constructed as described above, the rotational force is transmitted to the orbiting scroll 7 through the rotary shaft 18.
That is, the orbiting scroll 7 is driven by the eccentric bush 28 of the drive device 25 attached to the rotary shaft 18 inserted in the boss hole 27 of the boss portion 13 of the scroll, and does not rotate with respect to the fixed scroll 6 by the Oldham coupling 33. Can be revolved in a circular orbit. Then, the fixed scroll 6 and the orbiting scroll 7 gradually reduce the compression space 14 formed by these scrolls from the outside to the inside, and compress the air flowing in from the suction hole 31.
The compressed air is discharged from the discharge hole 32 of the end plate 8 of the fixed scroll 6.

The order of assembling the drive unit 25 will be described. First, the frame 4 is fixed to the motor cover 15 in which the electric element 3 is incorporated. At this time, a ball bearing 24 is incorporated in the main bearing 4 of the frame 4. In this state, the balance weight 26 is inserted into the rotating shaft 18 so as to contact the inner ring of the ball bearing 24. A pin 29 is set on the balance weight 26 inserted on the rotary shaft. Then, the eccentric bush 28 is inserted into the rotary shaft 18 so as to fit into the pin 29. Finally, the eccentric bush 28 is fixed to the rotary shaft 18 with the bolt 30. At this time, the needle bearing 38 and the seal member 34 are set between the boss portion 13 of the orbiting scroll 7 and the eccentric bush 28. The inner ring of the ball bearing 24 and the balance weight 26 are pressed and fixed to the step portion 20 of the rotary shaft by the tightening force of the bolt 30 that fixes the eccentric bush 28 to the rotary shaft 18. As a result, the drive device 25 is securely fixed by the single bolt 30.

Balance weight 26 and eccentric bush 28
By positioning with the pin 29, the unbalanced force generated by the orbiting of the orbiting scroll 7 during operation is reliably canceled by the balance weight 26.

Further, the drive device 25 is fixed to the rotary shaft 18 with a single bolt 30, so that the work of attaching each component is eliminated and the assembling process can be simplified.

The plurality of keys 4 of the Oldham coupling 33
Since 0 and 41 are formed by a plurality of convex portions 42 and 43 at each location, the sliding load per unit area applied to the side surface of each convex portion 42 and 43 (revolution so that the orbiting scroll 7 does not rotate). It is possible to reduce the sliding load), and it is possible to use a material having a low PV value, which is a criterion for material selection. Therefore, an inexpensive material having not so high hardness can be used as the material of the Oldham coupling 33, the manufacturing cost can be reduced, and the reduction of the sliding load reduces wear and abrasion due to sliding, and the orbiting scroll 7
The amount of advance (the degree of advancing angularly in the rotational direction) is maintained well, and the contact between the wrap 12 of the orbiting scroll 7 and the wrap 10 of the fixed scroll 6 is maintained as set,
The performance of the compressor can be improved and abnormal noise can be prevented.

Further, by using the synthetic resin material for the Oldham coupling 33, not only the reduction of the manufacturing cost can be further promoted, but also the weight and the durability of the compressor can be further improved.

In this embodiment, the Oldham joint 33 is described with the plurality of convex portions 42 and 43 formed, but the present invention is not limited to this, and the Oldham joint 33 is not limited to this.
Even if the key groove formed of a plurality of concave portions is formed in the above and the key formed of a plurality of convex portions is formed in the orbiting scroll or the frame, the same operational effect is obtained, and it does not depart from the present invention.

[0026]

As described above, according to the present invention, since the plurality of keys or key grooves of the Oldham coupling are formed by the plurality of convex portions or concave portions at each position, the side surfaces of the respective convex portions or concave portions are formed. It is possible to reduce the applied sliding load per unit area (sliding load for revolving the orbiting scroll so that it does not rotate), and it is possible to use a material having a low PV value, which is a reference for material selection. Become. Therefore, it is possible to use an inexpensive material that is not so high in hardness as the material of the Oldham coupling, which can reduce the manufacturing cost, and the reduction of the sliding load reduces wear and abrasion due to sliding, thereby promoting the progress of the orbiting scroll. Maintains a good angular amount (the degree to which it advances angularly in the direction of rotation) and keeps the contact between the orbiting scroll wrap and the fixed scroll wrap as set, improving the performance of the compressor and causing abnormalities. It is possible to prevent the generation of noise.

Further, by using the synthetic resin material, not only the reduction of the manufacturing cost can be further promoted, but also the weight and durability of the compressor can be further improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a scroll type air compressor showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing an Oldham coupling of the present invention.

[Explanation of symbols]

 2 scroll compression element 3 electric element 6 fixed scroll 7 rocking scroll 8, 11 end plate 10, 12 wrap 25 drive device 33 Oldham coupling 40, 41 key 42, 43 convex portion 44, 46 concave portion 45, 47 key groove

Claims (2)

[Claims] 1. A fixed structure comprising a scroll compression element and an electric element, the scroll compression element having a frame having a bearing at its center, an end plate fixed to the frame, and a spiral wrap standing on the end plate. Scroll and
An orbiting scroll having an end plate, a spiral wrap erected on one surface of the end plate, and a boss erected on the other surface, and the oscillating scroll not to rotate with respect to the fixed scroll. A scroll-type oil-free fluid machine comprising an Oldham coupling that revolves on a circular orbit, and compresses gas such as air by gradually reducing the compression space formed between the scrolls from the outside to the inside. The Oldham coupling has a plurality of keys or key grooves on the surface on the orbiting scroll side and the surface on the frame side, and each key or key groove is composed of a plurality of protrusions or recesses, On the orbiting scroll side surface and the frame side surface, a key groove or a key formed of a plurality of concave portions or convex portions is formed corresponding to a key or a key groove formed of the plurality of convex portions or concave portions. Are Scroll type oil-free fluid machine, wherein the door. 2. The scroll type oilless fluid machine according to claim 1, wherein the Oldham coupling is made of a synthetic resin material.