JPH05240174A - Scroll type fluid machine - Google Patents

Abstract

PURPOSE:To prevent the biting into a partner side end plate by the touch of an edge and fusion by using a material having a high hardness for one scroll and a material having a low hardness for the other to provide a hardness difference, and setting the lap height of the scroll having the high hardness lower than the scroll having the low hardness. CONSTITUTION:A turning scroll 14 is subjected to surface hardening treatment, and the surface hardness of a fixed scroll 10 is lowered. The height of the spiral lap 16 of the turning scroll is set lower than the height of the spiral lap 12 of the fixed scroll 10. Even when the turning scroll 14 is inclined by compressed gas force, at the time of operation, and does precession, the lap top end of the turning scroll on the outside never make contact with the end plate 11 of the fixed scroll 10, and the lap top end of the other soft fixed scroll 10 makes contact with the end plate of the turning scroll 14 and slides thereon. Thus, cut of the end plate can be avoided, and reliability can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type fluid machine.

[0002]

2. Description of the Related Art FIG. 5 is a vertical sectional view of a conventional scroll type compressor. In the figure, reference numeral 1 denotes a hermetic housing, which comprises a cup-shaped main body 2, a front end plate 4 fastened thereto by bolts 3, and a tubular member 6 fastened thereto by bolts 5. A rotary shaft 7 penetrating the tubular member 6 is rotatably supported by the housing 1 via bearings 8 and 9. A fixed scroll 10 and an orbiting scroll 14 are arranged in the housing 1.

The fixed scroll 10 is provided with an end plate 11 and a spiral wrap 12 provided upright on the inner surface of the end plate 11. The end plate 11 is fastened to the cup-shaped body 2 by bolts 13. The inside of the housing 1 is partitioned by bringing the outer peripheral surface of the end plate 11 and the inner peripheral surface of the cup-shaped body 2 into close contact with each other, a discharge cavity 31 is formed outside the end plate 11, and a suction cavity is formed inside the end plate 11. A chamber 28 is formed. A discharge port 29 is formed in the center of the end plate 11, and the discharge port 29 is opened and closed by a discharge valve 30. The orbiting scroll 14 includes an end plate 15 and a spiral wrap 16 provided upright on the inner surface of the end plate 15. The spiral wrap 16 has substantially the same shape as the spiral wrap 12 of the fixed scroll 10.

The orbiting scroll 14 and the fixed scroll 10
And are eccentric to each other by a predetermined distance, and are meshed with each other with an angle of 180 °. Thus, the tip seal 17 embedded in the tip surface of the spiral wrap 12 closely contacts the inner surface of the end plate 15, and the tip seal 18 embedded in the tip surface of the spiral wrap 16 closely contacts the inner surface of the end plate 11, The side surfaces of the spiral wraps 12 and 16 are in line contact with each other at a plurality of points to form a plurality of compression chambers 19a and 19b which are substantially point-symmetric with respect to the center of the spiral.

A drive bush 21 is provided inside the cylindrical boss 20 projecting from the central portion of the outer surface of the end plate 15 to form the slewing bearing 2.
An eccentric drive pin 25 eccentrically formed at the inner end of the rotating shaft 7 is slidably fitted in a slide groove 24 bored in the drive bush 21. ing. And this drive bush 21
A balance weight 27 for balancing the dynamic unbalance due to the orbiting motion of the orbiting scroll is attached to the. Between the outer peripheral edge of the outer surface of the end plate 15 and the inner surface of the front end plate 4, a rotation preventing mechanism 26 including a thrust bearing 36 and an Oldham's joint is provided. Reference numeral 37 is a balance weight fixed to the rotary shaft 7.

In the above structure, when the rotating shaft 7 is rotated, the orbiting scroll 1 is moved through the orbiting drive mechanism including the eccentric drive pin 25, the drive bush 21, the boss 20, and the like.
4 is driven and the orbiting scroll 14 is the Oldham joint 26.
While being prevented from rotating on its own axis, it makes a revolution revolution movement on a circular orbit having a radius of revolution revolution. Then, the line contact portions on the side surfaces of the spiral wraps 12 and 16 gradually move toward the center of the spiral, and as a result, the compression chambers 19a and 19b.
Moves toward the center of the spiral whilst reducing its volume. Along with this, the gas flowing into the suction chamber 28 through a suction port (not shown) is taken into the compression chambers 19a and 19b from the outer end openings of the spiral wraps 12 and 16, and is compressed at the center. The gas reaches the chamber 22, passes through the discharge port 29, pushes and opens the discharge valve 30, discharges into the discharge cavity 31, and then flows out from there through a discharge port (not shown).

In the conventional scroll compressor, either the fixed scroll 10 or the orbiting scroll 14 is subjected to a surface treatment to harden the surface to improve the seizure resistance and wear resistance of the spirally wrapped surface. It was At the same time, a bottom plate 100, which is made of a material having a high hardness different from that of the scroll material, is installed on the inner surface of the end plate on the scroll side that is not surface-treated to improve the seizure resistance and wear resistance of the end plate. I was aiming for. However, the bottom plate 100 slides on the scroll end plate under the frictional force of the tip seal 18 and the like during operation. Therefore, there is a problem that the bottom plate 100 is hard to fit into the base of the spiral wrap of the scroll, or wears the base of the wrap, which significantly reduces the strength of the wrap.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a scroll type compressor in which the bottom plate 100 is eliminated in order to solve the above-mentioned trouble. In such a scroll-type compressor, the orbiting scroll 14 receives an overturning moment due to the compressed gas force and makes an orbiting motion in a tilted state, that is, a so-called "scoring motion". At this time, the wrap tip portion of the scroll on the outer side of the orbiting scroll 14 (for example, when a material having a hard surface or a high surface hardness is used for the orbiting scroll) has a fixed scroll 10 (in this case, the fixed scroll has a low surface hardness). 6), the inner surface of the end plate 11 was subjected to edge contact as shown in FIG. 6, biting, cutting of the end plate, and seizure, welding, etc. occurred under more severe conditions.

An object of the present invention is to provide a scroll type fluid machine in which, when the bottom plate is abolished, biting into the mating end plate due to edge contact, cutting of the end plate, seizure or welding does not occur. It is a thing.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and relates to a scroll type fluid machine constituted by meshing a pair of scrolls with the following features. ..

(1) One scroll is subjected to a surface hardening treatment or is made of a material having a high hardness, and the other scroll is made of a material having a low hardness so that both scrolls have a difference in hardness and a scroll having a high hardness. The wrap height is lower than the wrap height of a scroll with low hardness.

(2) One scroll is subjected to a surface hardening treatment or is made of a material having a high hardness, and the other scroll is made of a material having a low hardness. A taper surface is formed at the tip of the wrap so that the tip surface descends from the inside to the outside.

(3) One scroll is subjected to a surface hardening treatment or is made of a material having a high hardness, and the other scroll is made of a material having a low hardness so that both scrolls have a difference in hardness and a scroll having a high hardness. Forming a crowning surface with a curvature at the tip of the lap.

[0014]

The present invention has the following functions. (1) By making the wrap height of the scroll having high hardness lower than that of the scroll having low hardness, it is possible to prevent the tip of the wrap from being caught in the end plate of the counterpart scroll, and the end plate from being cut. (2) By making the wrap tip of the scroll with high hardness a tapered surface that decreases the wrap height from the inside to the outside, avoiding edge contact of the wrap tip and biting into the end plate of the other scroll, end plate The cutting etc. can be prevented. (3) By forming the wrap tip of the scroll with high hardness with a crowned surface with curvature, it is possible to avoid edge contact of the wrap tip and to bite into the end plate of the other scroll or to cut the end plate. It is prevented.

[0015]

1 is a partial sectional view of an orbiting scroll 14 and a fixed scroll 10 according to a first embodiment of the present invention. In the case of the present embodiment, the orbiting scroll 14 is subjected to a surface hardening treatment, and the fixed scroll 10 is an example having a lower surface hardness. 16 is a spiral wrap of the orbiting scroll 14,
12 is a spiral wrap of the fixed scroll 10, 17,
18 is a tip seal for each scroll. In this embodiment, the height of the orbiting scroll spiral wrap 16 is
It is formed lower than the height of the fixed scroll spiral wrap 10.

In the scroll type compressor of the present embodiment, during operation, the orbiting scroll is tilted by the compressed gas force, and even if the orbiting scroll is moved, the wrap tip of the outward orbiting scroll is fixed scroll. The end of the wrap of the other soft fixed scroll contacts the end plate of the orbiting scroll without contacting the end plate of the orbiting scroll. In this part, it slides without biting. As a result, cutting of the end plate is avoided and reliability can be improved.

FIG. 2 is a contact state diagram of the spiral wrap 16 and the fixed scroll end plate 11 of the orbiting scroll of the second embodiment of the present invention. Also in the present embodiment, the spiral wrap 16 of the orbiting scroll is subjected to the surface hardening treatment, and the fixed scroll end plate 11 has a lower surface hardness. FIG. 3 shows the orbiting scroll 14 of the above embodiment and its sectional view. The tip of the spiral wrap 16 of the orbiting scroll 14 is formed with a tapered surface 200 having an angle θ from the inside to the outside. The angle θ is determined by the following relational expression.

[0018]

[Equation 1]

In the scroll type compressor of this embodiment, during its operation, the orbiting scroll is tilted by the compressed gas force, and the wrapping tip of the orbiting scroll on the outer side is moved to perform the rubbing motion so that the end of the fixed scroll is reached. Even if it comes into contact with the plate, it does not hit the edge and slides on the end plate of the fixed scroll, cutting of the end plate is avoided, and reliability can be improved.

FIG. 4 is a contact state diagram of the orbiting scroll spirally wound wrap 16 and the fixed scroll end plate 11 according to the third embodiment of the present invention. Also in the case of this embodiment, the spiral wrap 16 of the orbiting scroll has been subjected to a surface hardening treatment,
The fixed scroll end plate 11 is an example having a lower surface hardness. At the tip of the orbiting scroll spiral wrap 16, the inclination angle of the orbiting scroll 14 determined by the gap formed between the tip of the spiral wrap 16 of the orbiting scroll 14 and the fixed scroll end plate 11,
A crowning surface 300 having a curvature that minimizes the surface pressure is formed.

In the scroll type compressor of the present embodiment, during its operation, the orbiting scroll is tilted by the compressed gas force to perform a grooving motion so that the wrap tip of the outer orbiting scroll is the end of the fixed scroll. Even if it comes into contact with the plate, it does not hit the edge and slides on the end plate of the fixed scroll, cutting of the end plate is avoided, and reliability can be improved.

In any of the above three examples, one scroll may be made of a material having high hardness instead of the surface hardening treatment.

[0023]

In the scroll type fluid machine of the present invention, one scroll is surface-hardened or a material having a high hardness is used, and a material having a low hardness is used for the other scroll, and the difference in hardness between the scrolls is used. In addition, the wrap height of the scroll with high hardness is lower than the wrap height of the scroll with low hardness, or there is a difference in hardness and the tip of the wrap of the scroll with high hardness goes from the inside to the outside. Since the tip surface is tapered or a crowning surface with curvature is formed, when the bottom plate is abolished, it bites into the mating end plate by edge contact, cutting the end plate,
It is possible to prevent the occurrence of seizure or welding.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing a contact state between an orbiting scroll and a fixed scroll according to a first embodiment of the present invention.

FIG. 2 is a partial sectional view showing a contact state between an orbiting scroll and a fixed scroll according to a second embodiment of the present invention.

FIG. 3 is a sectional view of the orbiting scroll of the above embodiment.

FIG. 4 is a partial cross-sectional view showing a contact state between an orbiting scroll and a fixed scroll according to a third embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view of a conventional scroll compressor.

FIG. 6 is a partial cross-sectional view showing a contact state between an orbiting scroll and a fixed scroll in a conventional scroll compressor.

[Explanation of symbols]

 10 Fixed Scroll 11 End Plate of Fixed Scroll 12 Whirlpool Wrap of Fixed Scroll 14 Orbiting Scroll 15 End Plate of Orbiting Scroll 16 Whirlpool Wrap of Orbiting Scroll 17 Chip Seal 18 Chip Seal 100 Bottom Plate 200 Tapered Surface 300 Crowning Surface

Claims (3)

[Claims] 1. A scroll type fluid machine comprising a pair of scrolls meshing with each other, wherein one scroll is subjected to a surface hardening treatment or is made of a material having high hardness,
A scroll-type fluid machine characterized in that a material having a low hardness is used for the other scroll so that both scrolls have a hardness difference and the wrap height of the scroll having a high hardness is made lower than that of the scroll having a low hardness. 2. A scroll type fluid machine comprising a pair of scrolls meshing with each other, wherein one scroll is surface hardened or a material having high hardness is used.
The other scroll is made of a material with low hardness, and both scrolls have a difference in hardness, and the scroll has a high hardness, and a tapered surface whose tip surface descends from the inside to the outside is formed at the wrap tip. Scroll type fluid machinery. 3. A scroll type fluid machine comprising a pair of scrolls meshing with each other, wherein one scroll is surface hardened or a material having high hardness is used.
A scroll-type fluid characterized in that a material with low hardness is used for the other scroll, and both scrolls have a hardness difference, and a crowned surface with a curvature is formed at the tip of the wrap of the scroll with high hardness. machine.