JP2005140072A - Scroll compressor - Google Patents

Abstract

A housing portion of an eccentric bearing in an orbiting scroll component has a thin end plate of the orbiting scroll component, and is greatly deformed to the fixed scroll component side due to a differential pressure between discharge pressure and suction pressure. The contact surface pressure of the fixed scroll tooth tip is increased by contact with each other, causing galling to each other, resulting in a reduction in compression efficiency and durability as a compressor.
The tooth bottom 4b of the orbiting scroll 4 is arranged such that the thrust direction gap between the tooth bottom 4b of the orbiting scroll part 4 and the tooth tip 2a of the fixed scroll part 2 increases from the outer peripheral side to the inner peripheral side. In the housing portion 13 of the eccentric bearing 12 of the orbiting scroll component 4, a flat portion 14 that is the largest is provided.
[Selection] Figure 1

Description

  The present invention relates to a scroll compressor used in an air conditioner, a cooling device such as a refrigerator, or a hot water supply device.

  As the refrigerating and air-conditioning hermetic compressors, there are a reciprocating type, a rotary type, and a scroll type, and any type has been used in the field of refrigeration and air conditioning for home use and business use. Currently, it is growing by taking advantage of its features in terms of cost and performance.

  Among them, a compressor in which a compression mechanism and an electric mechanism are housed in a container is represented by a so-called hermetic compressor intended for soundproofing and maintenance-free, and a scroll compressor and a rotary compressor are mainly used. In general, a scroll compressor forms a compression chamber between the fixed scroll part and the orbiting scroll part where the spiral wrap rises from the end plate, and forms a compression chamber between the two parts. , The compression chamber moves while changing its volume, thereby performing suction, compression, and discharge.

  A scroll compressor according to the prior art is taken as an example (for example, Patent Document 1). FIG. 7 is a sectional view of the scroll compressor. The refrigerant gas sucked from the suction pipe 1 passes through the suction air 3 of the fixed scroll part 2 composed of the wrap part 2a and the end plate 2b, and is engaged with the orbiting scroll part 4 composed of the wrap part 4a and the end plate 4b. , Compressed while decreasing in volume toward the center, and discharged from the discharge port 6.

  The back pressure chamber 8 formed by being surrounded by the fixed scroll component 2 and the bearing 7 must always have a back pressure that does not allow the orbiting scroll component 4 to be separated from the fixed scroll component 2. However, when this back pressure becomes excessive, the orbiting scroll component 4 is strongly pressed against the fixed scroll component 2, leading to abnormal wear of the scroll sliding portion and an increase in input. For this reason, it is necessary to always keep the back pressure constant. Therefore, a back pressure adjusting mechanism 9 is provided. The back pressure adjusting mechanism 9 is provided with a valve 11 in a passage 10 that communicates from the back pressure chamber 8 to the suction space 3 through the inside of the fixed scroll part 2, and the pressure of the back pressure chamber 8 is set. When the pressure becomes higher, the valve 11 is opened and the oil in the back pressure chamber 8 is supplied to the suction space 3 to maintain the back pressure chamber at a constant intermediate pressure.

  The above-described intermediate force is applied to the rear surface of the orbiting scroll component 4 to suppress overturning during operation. If it is overturned, the fixed scroll component 2 and the orbiting scroll component 4 are separated from each other, and leakage occurs at that portion. Further, the oil supplied to the suction space 3 moves to the compression chamber 5 along with the swiveling motion, and serves to prevent leakage between the compression chambers.

Also, for the wrap part of the orbiting scroll part or fixed scroll part, the height dimension from the tooth bottom to the tooth tip of the end plate is adjusted based on the result of measuring the temperature distribution of the tooth tip surface, and each lap is assembled in the assembled state. The thrust direction gap that is the largest on the innermost circumference side is formed between the tooth tip of the part and the other tooth bottom, or the thrust direction gap is formed so as to change in multiple stages. (For example, refer to Patent Document 2).
JP 2001-280252 A Japanese Patent Laid-Open No. 7-197891

  However, in the conventional configuration as described in Patent Document 2, each compression chamber formed between the fixed scroll component and the orbiting scroll component is compressed by the compression action, so that each lap portion is compressed. Although thermal expansion is considered, deformation of the fixed scroll component and the orbiting scroll component due to the pressure difference between the discharge pressure and the suction pressure of the compressor is not considered. In particular, the housing part of the eccentric bearing in the orbiting scroll part has a small thickness of the end plate of the orbiting scroll part, and is largely deformed to the fixed scroll part side due to the differential pressure between the discharge pressure and the suction pressure, and is fixed to the tooth bottom of the orbiting scroll. The contact surface pressure of the scroll tooth tips increased by contact with each other, causing galling to each other, resulting in a reduction in compression efficiency and durability as a compressor.

  Accordingly, the present invention has been made in view of the above-described conventional problems, and a scroll compressor that realizes high reliability and high efficiency from the initial operation stage in consideration of pressure deformation in the housing portion of the eccentric bearing in the orbiting scroll. It is intended to provide.

  In order to solve the conventional problems, in the scroll compressor of the present invention, the thrust direction gap between the tooth bottom of the orbiting scroll part and the tooth tip of the fixed scroll part increases from the outer peripheral side to the inner peripheral side. The bottom of the orbiting scroll and the tip of the fixed scroll are arranged so that the gap in the thrust direction is uniform and maximum at least in the range corresponding to the housing portion of the bearing of the orbiting scroll component. Formed.

  As a result, even if the pressure deformation due to the differential pressure between the discharge pressure and the suction pressure occurs in the housing portion of the eccentric bearing where the thickness of the end plate of the orbiting scroll is small, the tooth bottom of the orbiting scroll and the tooth tip of the fixed scroll are separated. The aim is to achieve high reliability and high efficiency from the initial operation because it does not hit and contacts uniformly.

  The scroll compressor according to the present invention optimizes the shape of the orbiting scroll and the fixed scroll so that the bottom of the orbiting scroll and the tip of the fixed scroll are in uniform contact with each other, providing high reliability and high efficiency from the initial operation. Can be realized.

  The first invention provides an inclination so that the thrust direction gap between the tooth bottom of the orbiting scroll part and the tooth tip of the fixed scroll part increases from the outer peripheral side to the inner peripheral side, and the thrust direction gap The thickness of the end plate of the orbiting scroll is small by forming the bottom of the orbiting scroll and the tip of the fixed scroll so as to be uniform and maximum at least in a range corresponding to the housing portion of the bearing of the orbiting scroll component. Even in the case of pressure deformation due to the differential pressure between the discharge pressure and the suction pressure in the eccentric bearing housing, the tooth bottom of the orbiting scroll and the tip of the fixed scroll do not come into contact with each other, making contact evenly. Reliability and high efficiency can be realized from the initial operation.

  In particular, the second invention is such that the thrust direction gap between the root of the orbiting scroll component of the first invention and the tip of the fixed scroll increases from the outer peripheral side to the inner peripheral side. The tooth bottom forms an inclined surface which is concave from the outer peripheral side to the inner peripheral side with respect to the fixed scroll, and at least the concave portion at the tooth bottom of the orbiting scroll corresponding to the housing portion of the bearing of the orbiting scroll component Even if pressure deformation due to the differential pressure between the discharge pressure and the suction pressure occurs in the housing portion of the eccentric bearing where the thickness of the end plate of the orbiting scroll is small, Because it has a shape that takes deformation into account, the tooth bottom of the orbiting scroll and the tip of the fixed scroll do not come into contact with each other, making contact evenly, providing high reliability and high reliability from the initial operation. It is possible to realize the rate.

  According to a third aspect of the present invention, there is provided an inclined surface so that the lap height is reduced from the outer peripheral side to the inner peripheral side, particularly at the tooth tip of the fixed scroll part of the first invention, and at least the housing of the bearing of the orbiting scroll part In the housing portion of the eccentric bearing in which the thickness of the end plate of the orbiting scroll is small by providing a flat portion in which the height of the lap portion of the fixed scroll facing the tooth bottom of the orbiting scroll corresponding to the portion is the minimum height dimension, Even when pressure deformation due to the differential pressure between the discharge pressure and the suction pressure occurs, the tooth tip of the fixed scroll has a shape that takes pressure deformation into account. It is possible to achieve high reliability and high efficiency from the initial operation without contact with each other and even contact.

  The fourth aspect of the invention is such that the thrust direction gap between the tooth tip of the orbiting scroll part and the bottom of the fixed scroll part of the first to third inventions increases from the outer peripheral side to the inner peripheral side. By providing an inclination to the tooth tip of the scroll component, the heat of compression is generated in the central portion during the compression process, resulting in a high temperature. Therefore, it is possible to prevent the tooth tip in the central portion from becoming higher due to thermal expansion and coming into contact. .

  The fifth aspect of the invention is particularly fixed so that the thrust direction gap between the tooth tip of the orbiting scroll part and the bottom of the fixed scroll part of the first to third inventions increases from the outer peripheral side to the inner peripheral side. By providing an inclination on the tooth bottom of the scroll component, the heat of compression is generated in the central part during the compression process, resulting in a high temperature, so that the tooth tip of the central part can be prevented from becoming higher due to thermal expansion and contacting. .

  In the sixth aspect of the invention, in particular, the orbiting scroll of the first to fifth aspects of the invention is subjected to surface treatment with an alumite film treatment, PVD treatment, or nickel phosphorus plating treatment as a surface treatment. It is possible to operate without suppressing seizure and burning. In addition, even in transient operation where the return of the liquid refrigerant is severe in a system with a large capacity and multiple refrigerants, the liquid refrigerant ensures high reliability without seizure even if the lubricating oil runs out or the temperature rises on the thrust surface of the orbiting scroll. Can be secured.

  According to the seventh aspect of the present invention, in particular, the refrigerant of the first to sixth aspects is a high-pressure refrigerant, for example, carbon dioxide, so that even if the tooth bottom of the orbiting scroll is deformed by pressure, galling and abnormal wear are effectively prevented. be able to.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 to 3 show an embodiment of the present invention. In the embodiment, the same components as those of the conventional technique shown in the background art described above are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 1 shows a cross-sectional view of a compression element of a scroll compressor according to a first embodiment of the present invention. FIG. 2 shows a front view of the orbiting scroll component. As shown in the figure, the orbiting scroll component 4 is set so that the thrust direction gap between the tooth bottom 4b of the orbiting scroll component 4 and the tooth tip 2a of the fixed scroll component 2 increases from the outer peripheral side to the inner peripheral side in the normal temperature state. The tooth bottom 4b is inclined. Further, in the housing portion 10 of the eccentric bearing 9 shown by the hatched portion in FIG. 2, a flat portion 14 is provided on the tooth bottom 4 a of the orbiting scroll component 4.

An example of this inclination will be described in more detail. FIG. 3 shows the shape of the tooth bottom 4b of the orbiting scroll component 4 after high load operation. The tooth bottom 4b of the orbiting scroll part 4 is pressed against the fixed scroll part when a high pressure is applied to the rear face of the end plate, and has a shape as shown in FIG. In particular, in the housing portion 13 of the eccentric bearing 12 of the orbiting scroll component 4, since the end plate thickness is the thinnest, the flat portion 14 having the minimum end plate thickness as shown in the figure is formed by pressure deformation.

  Therefore, the same shape as the figure is provided so that the tooth bottom 4b of the orbiting scroll component 4 and the tooth tip 2a of the fixed scroll component 2 are received with uniform surface pressure.

  With the above configuration, even when pressure deformation due to the differential pressure between the discharge pressure and the suction pressure occurs in the housing portion 13 of the eccentric bearing 12 in which the end plate of the orbiting scroll component 4 has a small thickness, the tooth bottom 4b of the orbiting scroll component 4 is generated. Since the tooth tip 2a of the fixed scroll component 2 does not come into contact with each other and contacts uniformly, high reliability and high efficiency can be realized from the initial operation.

  Further, as shown in FIG. 4, the tooth tip 2 a of the fixed scroll component 2 is inclined so that the lap height decreases from the outer peripheral side to the inner peripheral side, and the housing portion of the eccentric bearing 12 of the orbiting scroll component 4 Needless to say, the same effect can be obtained by providing the flat portion 14 in which the height of the tooth tip 2a of the fixed scroll component 2 is the minimum height dimension in a range facing 13.

(Embodiment 2)
FIG. 5 shows a cross-sectional view of the compression element of the scroll compressor according to the second embodiment of the present invention.

  As shown in the figure, the thrust direction gap between the tooth tip 4a of the lap portion of the orbiting scroll component 4 and the tooth bottom 2b of the end plate of the fixed scroll component 2 increases from the outer peripheral side to the inner peripheral side at room temperature. The tip 4a of the lap part of the orbiting scroll component 4 is provided with an inclination.

  Since compression heat is generated in the central portion during the compression process and the temperature becomes higher, the tooth tip 4a of the orbiting scroll component 4 becomes higher due to thermal expansion toward the central portion, but the thrust direction gap is increased from the outer peripheral side to the inner peripheral portion. Since the tooth tip 4a of the lap portion of the orbiting scroll component 4 is inclined so as to increase toward the side, reliability and high efficiency from the initial operation can be achieved without contacting the tooth bottom 2b of the fixed scroll component 2. Can be realized.

  Further, as shown in FIG. 6, the fixed scroll component 2 so that the thrust direction gap between the tooth tip 4 a of the orbiting scroll component 4 and the tooth bottom 2 b of the fixed scroll component 2 increases from the outer peripheral side to the inner peripheral side. It goes without saying that the same effect can be obtained by providing an inclination to the tooth bottom 2b.

(Embodiment 3)
The fixed scroll component 2 is formed of an iron-based material, and the orbiting scroll component 4 is subjected to a surface treatment on an aluminum-based material, and a hardened layer is formed on the surface thereof. As this surface treatment, an alumite film treatment, PVD treatment, nickel phosphorus plating treatment or the like is performed.

  With the above configuration, the discharge pressure of the compressor is high, and when the back scroll pressure is applied so that the orbiting scroll component 4 is not pulled away from the fixed scroll component 2, the orbiting scroll component 4 is strongly pressed against the fixed scroll component 2, A highly reliable scroll compressor can be obtained without seizure due to the hardened layer formed by the surface treatment applied to the scroll component 4. Also, in a system with a large capacity and a large number of refrigerants, a severe liquid return to the scroll compressor occurs during transient operations such as starting and defrosting, and this liquid return causes the lubricating oil to be washed with the liquid refrigerant, resulting in severe lubrication. However, it is not seized by the hardened layer by this surface treatment, and high speed operation is possible.

Further, when the refrigerant is a high-pressure refrigerant such as carbon dioxide, the discharge pressure of the compressor is about 7 to 10 times higher than the high-pressure side pressure of a conventional refrigeration cycle using chlorofluorocarbon as the refrigerant. In consideration of the temperature distortion and pressure deformation of the orbiting scroll component 4 and the fixed scroll component 2, the crawl compressor is highly reliable and highly efficient from the beginning of operation because it receives a uniform contact pressure without local contact. Can be realized.

  As described above, since the scroll compressor according to the present invention can achieve high reliability and high efficiency by optimizing the shapes of the orbiting scroll and the fixed scroll, the working fluid is not limited to the refrigerant. It can also be applied to scroll fluid machinery applications such as air scroll compressors, vacuum pumps, oil-free compressors, and scroll type expanders.

The figure which shows the compression mechanism part of the scroll compressor in Embodiment 1 of this invention. Front view of the orbiting scroll component in Embodiment 1 of the present invention The figure which shows the tooth bottom shape of the turning scroll components after the high load operation in Embodiment 1 of this invention. The figure which shows the compression mechanism part of the 2nd scroll compressor in Embodiment 1 of this invention. The figure which shows the compression mechanism part of the scroll compressor in Embodiment 2 of this invention. The figure which shows the compression mechanism part of the 2nd scroll compressor in Embodiment 2 of this invention. Vertical sectional view of a scroll compressor showing a conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Suction pipe 2 Fixed scroll component 2a Tooth tip of fixed scroll component 2b Tooth base of fixed scroll component 3 Suction chamber 4 Orbiting scroll component 4a Tooth tip of orbiting scroll component 4b Tooth bottom of orbiting scroll component 5 Compression chamber 6 Discharge port 7 Bearing 8 Back pressure chamber 9 Back pressure adjustment mechanism 10 Communication path 11 Valve 12 Eccentric bearing 13 Housing part 14 Flat part

Claims (7)

When the fixed scroll part and the orbiting scroll part where the spiral wrap rises from the end plate are meshed to form a compression chamber between them, and the orbiting scroll part is turned along a circular path under the rotation restraint by the rotation restraint mechanism In a scroll compressor that performs suction, compression, and discharge by moving the compression chamber while changing the volume, a thrust direction gap between the tooth bottom of the orbiting scroll component and the tooth tip of the fixed scroll component is The orbiting scroll is provided with an inclination so as to increase from the inner circumference side to the inner circumference side, and the thrust direction gap is uniform and maximum at least in a range corresponding to the housing portion of the bearing of the orbiting scroll component. A scroll compressor characterized by forming a tooth bottom and a tooth tip of the fixed scroll. The bottom of the orbiting scroll has an outer periphery relative to the fixed scroll so that a thrust direction gap between the bottom of the orbiting scroll and the tip of the fixed scroll increases from the outer peripheral side to the inner peripheral side. An inclined surface that is concave from the side to the inner peripheral side is formed, and a flat portion that is the largest concave portion is provided at least in the tooth bottom of the orbiting scroll corresponding to the housing portion of the bearing of the orbiting scroll component. The scroll compressor according to claim 1. An inclined surface is provided on the tooth tip of the fixed scroll part so that the lap height decreases from the outer peripheral side to the inner peripheral side, and at least facing the tooth bottom of the orbiting scroll corresponding to the housing portion of the bearing of the orbiting scroll part. The scroll compressor according to claim 1, wherein a flat portion having a minimum height dimension is provided for the height of the wrap portion of the fixed scroll. The tooth tip of the orbiting scroll part is inclined so that the thrust direction gap between the tooth tip of the orbiting scroll part and the tooth bottom of the fixed scroll part increases from the outer peripheral side to the inner peripheral side. The scroll compressor according to any one of claims 1 to 3. The fixed scroll part has an inclined bottom so that a thrust gap between the tooth tip of the orbiting scroll part and the bottom of the fixed scroll part increases from the outer peripheral side to the inner peripheral side. The scroll compressor according to any one of claims 1 to 3. The scroll compressor according to any one of claims 1 to 4, wherein the orbiting scroll is subjected to any one of alumite film treatment, PVD treatment, and nickel phosphorus plating treatment as a surface treatment. The scroll compressor according to any one of claims 1 to 5, wherein the refrigerant is a high-pressure refrigerant, for example, carbon dioxide.

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