JPH10213081A - Lap structure for scroll fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve air tightness in a spiral chamber, simplify a structure of a scroll fluid machine by forming scroll members independently from end plates and laps, and inserting the spiral lap made of a resin material to recessed shaped spiral grooves of a rectangular cross section formed on one side of the end plate freely to slightly move in the axial direction. SOLUTION: Recessed shaped spiral grooves 10b, 12b of a rectangular cross section, in which end parts of laps 11, 13 are inserted, are formed on the front surface of the end plate 10a of a driving scroll 10 and on the front surface of the end plate 12a of a driven scroll 12. A driving shaft 10c is erected on a back surface center part of the end plate 10a, and a hollow driven shaft 12c is erected on the back surface center part of the end plate 12a. Laps 11, 13 arranged between the end plates 10a, 12a are formed slightly shorter than the length between spiral groove bottoms 10d, 12d and mating end plate sliding surfaces 12e, 103 freely to move in the axial direction slightly. Therefore, the laps 11, 13 are pushed down on the mating end plate sliding surfaces 12e, 10e, a clearance between tip ends of the laps 11, 13 and the mating end plate sliding surfaces 12e, 10e is eliminated, and thereby, leakage of the axial direction is surely prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll fluid machine used for a compressor, an expander, a vacuum pump, a fluid motor and the like, and more particularly to a wrapping of a scroll member used for an oilless air compressor and an oilless vacuum pump. It relates to the improvement of the structure.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 6 (a), a driving scroll 1 having a first wrap 1b formed on an end plate 1a and a driven scroll 2 having a second wrap 2b formed on an end plate 2a. The two wraps 1b, 2b are arranged side by side with the wraps 1b, 2b facing each other. The swirl chamber formed by the two wraps 1b, 2b is compressed and moved toward the center, and the high-pressure fluid is discharged from the discharge port 2c. A scroll fluid machine configured to be able to exhaust to the outside is known. In this type of compressor or vacuum pump, improving the airtightness of the spiral chamber is an important factor for improving the performance efficiency. Therefore, an oil seal system using an oil lubricant has been adopted. A non-lubricated air compressor, in which a concave spiral groove is formed at the tip of the wrap, a seal member 3 is interposed between sliding surfaces of the end plates facing each other to improve the airtightness of the spiral chamber in the axial direction, A vacuum pump has been developed.

[0003]

However, FIG.
As shown in (b), in the case of a technique in which a concave spiral groove is formed at the tip of the wrap, a seal member 3 is interposed between sliding surfaces of the end plates facing each other to improve the airtightness in the axial direction of the spiral chamber, Since the gaps 4 and 5 at the tip of the wrap cannot be eliminated, there is a problem that leakage from the gap cannot be stopped. Furthermore, in order to improve the airtightness of the volute formed by both wraps, not only the airtightness in the axial direction,
It is also necessary to reduce the leakage between the peripheral walls of the meshed laps, so that attempts have been made to reduce the gap between the peripheral walls of the wraps. However, as shown in FIG. 6 (c), if the gap 6 between the peripheral walls is made smaller, the two wraps are made of metal, so that erroneous contact easily causes galling or the like, and the gap 6 has a limit. Was. Further, in order to make the gap 6 smaller, it is necessary to make the position and the shape accuracy of the related members extremely high, and there has been a problem that it has to be very expensive.

The present invention provides an inexpensive spiral chamber formed between both end plates by means of both wraps, in order to improve the airtightness of the vortex chambers, without the necessity of increasing the position and shape accuracy of related members. An object of the present invention is to provide a highly reliable wrap structure of a scroll fluid machine which does not cause galling or the like.

[0005]

In order to achieve the above object, in a scroll fluid machine according to the present invention, a pair of scroll members are formed separately from an end plate and a wrap. A concave spiral groove having a rectangular cross section is formed on the side,
A wrap structure formed of a resin material in each of the spiral grooves is formed into a wrap structure of a scroll fluid machine in which spiral wraps are inserted between opposing end plate surfaces so as to be slightly axially movable. is there.

Further, by forming both wraps in the shape of a strip having a rectangular cross section with a flexible resin material, the wraps can be easily and inexpensively formed simply by being inserted along the concave spiral grooves of both end plates. Is possible. Desirably, the resin material is a synthetic resin having heat resistance, abrasion resistance and self-lubricating property and having flexibility, or a composite material of metal and resin.

Further, by forming a plurality of wedge-shaped cuts on the inner side surface and the bottom surface of the wrap, leakage of fluid from between the peripheral walls of the meshed wraps is reduced.
In addition, it is possible to reduce the amount of fluid leaking to the low pressure side from the gap between the bottom surface of the wrap and the bottom of the spiral groove, and to seal the gap between the end plate surfaces facing each other.

[0008]

According to the first aspect of the present invention, since the wrap is movable in the axial direction, the wrap is pushed up to the sliding surface of the mating end plate by the differential pressure between the spiral chambers. In the technology of eliminating the gap between the sliding surfaces, preventing leakage in the axial direction, forming a concave spiral groove at the tip of the conventional wrap, and interposing a seal member between the sliding surfaces of the facing end plates, In the present invention, since a concave spiral groove is not formed at the tip of the wrap, the leakage can be prevented from occurring in the gaps beside the seal member, which could not be prevented. Furthermore, even if the gap between the peripheral walls is made smaller in order to reduce leakage between the peripheral walls of both meshed laps, the wraps are made of resin, so that galling does not occur even if they contact erroneously. Therefore, leakage between the peripheral walls can be easily reduced.

According to the second aspect of the present invention, a wrap formed in a rectangular cross-section strip shape with a flexible resin material is provided in a concave spiral groove having a rectangular cross section formed on one side of an end plate. Since the spiral wrap is inserted along the spiral groove, the spiral wrap is easy to process and inexpensive.

In the invention according to claim 3, in order to improve the airtightness of the spiral chamber formed by the two wraps,
It is necessary to reduce the leakage between the peripheral walls of both meshed wraps, but in order to make the gap smaller, it is necessary to make the position and shape accuracy of the related members extremely high, and if it is very expensive There is a problem that it is unavoidable and that if the wrap is made of metal, erroneous contact tends to cause galling or the like, but as in the present invention, the inner surface of the wrap has a plurality of By forming the wedge-shaped notch, even if the gap between the peripheral walls of both laps is large,
The formed plurality of wedge-shaped cuts are expanded and deformed by the pressure difference and are elastically pressed against the opposing side surfaces of the wrap, so that leakage between the peripheral walls can be reduced.

Further, in order to improve the airtightness of the spiral chamber in the axial direction, a plurality of wedge-shaped cuts are formed also on the bottom surface of the wrap, so that the formed plurality of wedge-shaped cuts expand and deform due to a pressure difference. Since the pressure is elastically pressed against the opposed bottom surfaces of the spiral grooves, the amount of fluid leaking to the low pressure side from the gap between the bottom surface of the wrap and the bottom of the spiral grooves can be reduced.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG.
1 is a cross-sectional view of the entire structure of an all-system rotary scroll fluid machine having a wrap structure to which the present invention is applied.

In the driving scroll 10, 10a is an end plate, and 11 is a wrap. Also, on the front surface of the end plate 10a,
A concave spiral groove 1 having a rectangular cross section into which the end of the wrap 11 is inserted.
0b is formed, and a drive shaft 10c is provided upright at the center on the back surface of the end plate 10a.

In the driven scroll 12, 12a is an end plate, and 13 is a wrap. Also, on the front surface of the end plate 12a,
A concave spiral groove 1 having a rectangular cross section into which the end of the wrap 13 is inserted.
2b is formed, and a discharge hole 16 is provided in the center,
The hole 16 is formed to communicate with a hollow driven shaft 12c erected at the center of the rear surface of the end plate 12a.

The spiral groove 10b of the driving scroll 10 and the spiral groove 12b of the driven scroll 12 are formed such that the spiral direction is reversed.
Can be configured by the same member by setting the fitting portion to the opposite side.

The wraps 11 and 13 of the driving scroll 10 and the driven scroll 12 configured as described above are meshed with each other, and the housings 14 and 15 are provided with the driving shaft 10 c and the driven shaft 12.
It is rotatably supported via c. The end plate 10a of the driving scroll 10 and the end plate 12a of the driven scroll 12
Between them, there is provided a connecting means (not shown) which transmits the rotational force of the driving scroll 10 to the driven scroll 12 and is capable of relatively revolving.

The wraps 11, 13 provided between the end plates 10a, 12a are slightly smaller than the length from the spiral groove bottoms 10d, 12d to the mating end plate sliding surfaces 12e, 10e in consideration of thermal expansion due to heat of compression. It is short.

In the scroll fluid machine, when the driving scroll 10 is driven to rotate, the driven scroll 12 is rotated synchronously by the action of the connecting means, and the driving scroll 10 and the driven scroll 12 perform relative orbital motion. By performing the relative orbital movement, the air taken in from the suction port 17 is taken into the volute formed by the two wraps 11 and 13 and is compressed and moved toward the center. Exhausted from 16

According to the present invention, in the scroll fluid machine, in order to improve the airtightness of the spiral chamber formed by the two wraps, the end plate of the scroll member and the wrap are formed separately, and the end plate of the scroll member is formed. A concave spiral groove having a rectangular cross section is formed on one side, and a wrap formed separately is inserted into the spiral groove between opposed end plate surfaces so as to be slightly axially movable. It is characterized by doing.

In the first embodiment of the present invention shown in FIGS. 1 and 2, a wrap 11 is provided in a spiral groove 10b of an end plate of a driving scroll 10, and a spiral groove 12b is provided in an end plate of a driven scroll 12. The wraps 13 are inserted in the direction of the arrow, and are engaged with each other. The height of each of the wraps 11, 13 is determined by the spiral groove bottoms 10d, 12 of each end plate.
It is formed slightly shorter than the distance between d and the mating end plate surfaces 12e and 10e in consideration of thermal expansion. In addition, each lap 1
The widths of the spiral grooves 10 and 13 are also slightly shorter than the spiral grooves 10b and 12b.

In the first embodiment, the wraps 11, 13
Is movable in the axial direction, the wrap is pressed against the sliding surfaces 12e and 10e of the mating end plates by the differential pressure between the spiral chambers, so that there is no gap between the leading end of the lap and the sliding surface of the mating end plate. Leakage can be prevented, and the conventional technology of forming a concave spiral groove at the tip of the wrap and interposing a seal member between the sliding surfaces of the facing end plates could not be prevented.
The leaks from the gaps 4 and 5 beside the seal member shown in FIG. 6B also occur because the present invention does not form a concave spiral groove at the tip of the wrap, so the gaps 4 and 5 beside the seal member are generated. No leakage can be prevented. Further, in order to reduce the leakage between the peripheral walls of the meshed laps, FIG.
Even if the gap 6 between the peripheral walls shown in (c) is made smaller, the two wraps are made of resin so that galling or the like does not occur even if they contact erroneously, so that leakage between the peripheral walls is easily reduced. I can do it.

FIG. 3 shows a second embodiment of the present invention. A flexible resin is provided on a concave spiral groove 10b having a rectangular cross section formed on one side of an end plate 10a of a driving scroll 10. As shown in FIG. Wrap 11 formed of a material into a strip shape having a rectangular cross section
Is inserted along the spiral groove 10b, so that an inexpensive spiral wrap that can be easily processed is obtained. The driven scroll 12 has the same configuration.

Regarding another configuration of the second embodiment,
This is the same as the first embodiment, and the operation is the same as that of the first embodiment.

Next, FIGS. 4A and 4B and FIG.
(A), (b), and (c) show a third embodiment of the present invention. In order to improve the airtightness of a spiral chamber formed by both wraps, the space between the peripheral walls of both wraps engaged with each other is shown. It is necessary to reduce the leakage of, but in order to make the gap smaller, it is necessary to make the position and shape accuracy of the related members extremely high, and it must be very expensive, If the wrap is made of metal, there is a problem that galling or the like is likely to occur if the wrap is made by mistake. However, referring to FIGS. 4 (a) and 4 (b), the wraps 11, 1
By forming a plurality of wedge-shaped cuts 11a and 13a on the inner surface of 3, even if the gap between the peripheral walls of both wraps is large, the formed plurality of wedge-shaped cuts are expanded and deformed by pressure, and face each other. Since it is elastically pressed against the side surface of the wrap, leakage between the peripheral walls can be reduced.

Referring to FIGS. 5 (a), 5 (b) and 5 (c), in order to improve the airtightness of the spiral chamber in the axial direction, a plurality of bottoms 11b and 13b of the wraps 11 and 13 are also provided. By forming the wedge-shaped cuts 11c and 13c, the formed plurality of wedge-shaped cuts 11c and 13c are expanded and deformed by pressure, and are elastically pressed against the opposed bottom surfaces 10d and 12d of the spiral groove. Bottom surface 11b, 13b
And the fluid leaking to the low pressure side from the gap between the spiral groove bottoms 10d and 13d can be reduced.

By forming the wraps of the driving scroll and the driven scroll separately from the resin material, the airtightness of the spiral chamber formed by the wraps can be further improved, and the structure is simple. There is an effect that an inexpensive scroll fluid machine can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the entire structure of an all-system rotary scroll fluid machine having a wrap structure according to the present invention.

FIG. 2 is a perspective view showing a driving scroll and a driven scroll having a wrap structure according to the present invention in an exploded state.

FIG. 3 is a perspective view showing the wrap formed in a rectangular cross section of the present invention in the middle of a spiral groove of an end plate.

FIG. 4 (a) is a horizontal cross-sectional view of a meshed wrap of a driving scroll and a driven scroll having the wrap structure of the present invention. FIG. 4B is an enlarged view of a portion A in FIG.

FIG. 5 (a) is a partial vertical cross-sectional view of a meshed wrap of a driving scroll and a driven scroll having the wrap structure of the present invention. (B) is a longitudinal sectional view showing a state in which the wedge-shaped cut portion of the wrap is expanded by a differential pressure when the wrap of the present invention is attached to the spiral groove on the driving scroll side.
(C) is a longitudinal sectional view showing a state in which the wedge-shaped cut portion of the wrap is expanded by a differential pressure when the wrap of the present invention is attached to the spiral groove on the driven scroll side.

FIG. 6A is a cross-sectional view of the entire structure of a conventional all-system rotary scroll fluid machine having a wrap structure. FIG. 7B is an enlarged sectional view of the seal member attached to FIG.
FIG. 7C is a partial horizontal cross-sectional view of the wrap of FIG.

[Explanation of symbols]

 1, 10 drive scroll 2, 12 driven scroll 3 seal member 11, 13 lap 10, 15 housing

Claims (3)

[Claims] 1. A pair of scroll members having a spiral wrap standing on one surface of an end plate are meshed with each other, and the two wraps are rotated by relative revolving motion. In the scroll fluid machine that sequentially reduces and moves the formed spiral chamber in the center direction and compresses and discharges the fluid, the pair of scroll members are formed separately as an end plate and a wrap, A concave spiral groove having a rectangular cross section is formed on one side of the end plate, and the wrap formed in a spiral shape with a resin material is slightly inserted between the opposed end plate surfaces in the spiral groove. A wrap structure for a scroll fluid machine which is fitted so as to be movable in the axial direction. 2. The scroll fluid machine according to claim 1, wherein the wrap is formed of a flexible resin material into a strip shape having a rectangular cross section, and is inserted along a concave spiral groove of the end plate. Wrap structure. 3. A plurality of wedge-shaped cuts are formed in the inner side surface and the bottom surface of the wrap, and the wrap is formed so as to be deformable in the expanding direction by receiving pressure applied to the wedge-shaped cuts. 2. A wrap structure for a scroll fluid machine according to claim 1.