JPH03275901A - Scroll type fluid machinery - Google Patents

Abstract

PURPOSE:To reduce the dimension of scroll type fluid machinery and improve compression efficiency by extending the inner peripheral edge and/or the outer peripheral edge of a lap on one side where a turning scroll and a fixed scroll are oppositely fitted, by 180 deg. in comparison with a lap on the other side. CONSTITUTION:On a fixed scroll 2, a fixed lap 10 is formed in spiral form from a bearing 5 part along the periphery of a center hole 4. A lap 15 on a turning scroll 1 side is extended by 180 deg. on the inner peripheral side, and a starting edge 15a can be approached or slidingly attached to a semicircular groove 20a at the starting edge 10a of the scroll groove of the lap 10. Accordingly, during the turn around a scroll shaft 1a, a sealed space 30 can be maintained until the lap edge 15a reached the inlet edge of a discharge port 7, and the compression efficiency can be improved in comparison with the conventional case where the sealed space is opened before by 180 deg., and the dimensional of a final compression chamber can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a scroll fluid machine that functions as a compressor, an expander, and a vacuum pump, and particularly relates to a scroll fluid machine that functions as a compressor, an expander, and a vacuum pump, and particularly relates to a scroll fluid machine that has a spiral wrap formed on at least one surface in the axial direction. a rotating scroll;
8. Related to a scroll fluid machine comprising one or more fixed scrolls having one helical wrap that fits into the wrap, and configured to be able to revolve around the orbiting scroll without rotating the orbiting scroll. A fixed scroll forming a first wrap in an enclosed casing and having an inlet and an outlet in its peripheral wall and center area, respectively, and a second wrap that can be fitted into the first wrap. and an orbiting scroll, for example, by revolving the orbiting scroll without rotating it, the gas introduced into the casing from the suction port is taken into the sealed space formed between the first and second wraps, A scroll type compressor is known in which the volume of the orbiting scroll is gradually reduced as the orbiting motion of the orbiting scroll revolves, the scroll is compressed by moving toward the center, and the high-pressure air is discharged to the outside from a discharge port.

Such a scroll fluid machine is a so-called face-to-face scroll fluid machine (for example, Japanese Patent Laid-Open No. 50-325
No. 12) and a pair of fixed scrolls each having wraps that can be fitted with the wraps are sandwiched between both sides of one orbiting scroll having wraps formed on both sides in the axial direction, and the orbiting scroll of one orbiting scroll has wraps formed on both sides in the axial direction. The so-called twin scroll fluid machine (Japanese Patent Publication No. 63-420
No. 81) has been proposed.

"Problem to be Solved by the Invention" However, in any of the above-mentioned scroll-type fluid machines, the wraps of both scrolls are fitted with almost the same number of turns and 180 degrees out of phase with each other, so that the suction The following problems occur on both the side and the discharge side.

That is, on the suction side, the start ends of the wraps located on the outer circumferential side of the scroll come into contact with the wall surface of the other wrap side at positions 180° out of phase with each other, and in order to form a compression chamber, suction is applied to each start end position of each wrap. or 1
It is necessary to provide a semi-circular detour on the outer circumferential side of the wrap that communicates with the first suction port provided at a position separated by 80 degrees, which results in an increase in the size of the device and the number of processing steps. . However, providing multiple suction ports as described above means that multiple compression chambers perform the compression process in parallel with a 180° phase shift, which makes it difficult to achieve high compression, and also makes it difficult to achieve high compression. The volume taken into the closed space becomes correspondingly smaller, and the suction efficiency cannot be improved.

On the other hand, on the discharge side, since the bearing for inserting the rotating shaft and other parts is located in the center of the scroll, the end of the wrap and the discharge port must be provided in the middle of the involute curve on the outer periphery of the bearing. However, if the start ends of the respective wraps are arranged with a phase shift of 180° in this state, the final compression chamber will be opened to the discharge port while remaining large in volume, resulting in a small compression ratio.

However, the large volume of the final compression chamber increases the length of the seal line, resulting in a decrease in sealing performance and a tendency to cause backflow, leading to a decrease in compression efficiency.

In order to overcome these drawbacks, in so-called face-to-face scroll fluid machines, the main axis of the orbiting scroll is provided on the back side of the wrap, while the discharge port is provided in the center of the fixed scroll. In a machine, as shown in the example below, an orbiting scroll is arranged between a pair of fixed scrolls, so the main shaft must be disposed so as to pass through the center of the fixed scroll. In a fluid machine that adopts this configuration, the above-mentioned drawbacks inevitably become apparent.

In view of the drawbacks of the prior art, it is an object of the present invention to provide a scroll-type fluid machine that can achieve high suction efficiency and high compression while reducing the size of the device on the suction side.

Another object of the present invention is to provide a scroll-type fluid machine that can improve discharge efficiency and achieve high compression.

Another object of the present invention is to provide a scroll-type fluid machine that improves the sealing performance between wraps and the compression efficiency.

"Means to solve problems" The present invention will be explained separately for both the suction side and the discharge side.

On the suction side, one wrap, especially the fixed scroll side wrap outer circumferential edge, is extended by approximately 180 degrees, and its circumferential edge is substantially aligned with the other wrap circumferential edges.

Since the wrap peripheral edges located on the outer circumferential side of the scroll coincide with each other, it is sufficient to provide a suction port at the corresponding portion, and as a result, the suction port of L is sufficient, and there is no need to provide a detour. This leads to smaller equipment and reduced processing man-hours.

In addition, in the present invention, by extending the circumferential edge of the wrap by 180 degrees, the intake volume itself, which is the first sealed space of the wrap, becomes larger than before, which improves the suction efficiency, and also makes the suction port -
Since compression is performed by gradually reducing one sealed space from the suction position to the discharge position, it is possible to improve compression efficiency and achieve high compression.

On the other hand, on the discharge side, the volume of the final compression chamber can be minimized by extending the inner circumferential edge of the wrap of the orbiting scroll approximately 180 degrees and extending the circumferential edge of the wrap to the vicinity of the discharge port. It is possible to improve the discharge efficiency and increase the compression ratio.

By arranging the wrap end surface so that it substantially slides along the wall surface of the other side scroll, the sealing performance is also improved on the wrap end side. In this case, the wrap peripheral edge and the discharge port are directly faced to each other. By forming the discharge port on the inner side of the scroll center-side peripheral wall surface through the conduction path, the above effect is further enhanced.

Further, it is preferable that the radius of the semicircular shape of the peripheral wall surface is set to be approximately the same as the eccentricity of the orbiting scroll and the fixed scroll, or in other words, the turning radius.

Furthermore, as described above, when the volume of the final compression chamber is reduced, the seal line is also shortened, resulting in improved sealing performance and prevention of backflow, leading to improved compression efficiency.

"Embodiments" Hereinafter, preferred embodiments of the present invention will be described in detail by way of example with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, and relative arrangements of the components described in this example are not intended to limit the scope of this invention, but are merely illustrative examples. It's nothing more than that.

One orbiting scroll 1 has orbiting wraps formed on both sides in the axial direction, a pair of fixed scrolls 2A and 2B have fixed wraps that fit on each of the wraps, and 120° angles are formed on the outer peripheral sides of the scrolls. It is composed of three eccentric rotating shafts 3 for regulating rotation, which are provided at positions shifted in the central direction.

The fixed scrolls 2A and 2B have a dome shape, and their peripheral walls functioning as casings are brought into contact with each other via a sealing member to form a sealed space therein, and a main shaft 6 is connected to the center hole 4 of the fixed scrolls 2A and 2B through a bearing 5 through a bearing 5. The main shaft 6 is rotatably supported at two points.

Around the bearing 5, spiral fixed wraps 10 are arranged symmetrically so as to face each other, as will be described later, and a discharge lower and a suction port are provided at the center region side and the outer peripheral edge of one fixed scroll, respectively. form 8.

On the other hand, as described above, the orbiting scroll 1 has orbiting wraps 15 formed on both surfaces in the axial direction, and is configured to be able to fit with the fixed wrap 10, and the eccentric rotating shaft 3 is pivotally supported on the peripheral edge side thereof. The supporting shafts on both sides of the skeleton eccentric rotating shaft 3 are supported by the fixed scrolls 2A and 2B, and the rotation of the orbiting scroll 1 is restricted by two-point support.
12B is a tip seal fitted to the tip of the wrap.

Since such a configuration is publicly known, a detailed explanation thereof will be omitted;
In the twin-type scroll compressor, the bearing 5 that passes through the main shaft 6 must be provided at the center of the pair of fixed scrolls 2A and 2B, or in other words, the discharge lower must be installed outside the center. However, the above-mentioned problem occurs.

Therefore, in order to eliminate the above-mentioned drawbacks, in this embodiment, the first
It has a wrap shape as shown in the figure and FIG. 2.

For example, in Fig. 1, 1.0 is a wrap formed on two fixed scrolls, and a spiral shape is formed from five bearings formed in an involute shape along the circumference of a center 64 that supports a main shaft 6 provided at the center. It is formed with a number of turns of approximately 5.5π (2°75 turns), and the lap start discharge lower is perforated.

In this case, the radius of the circumferential wall surface is set to be approximately the same as the eccentricity X of the orbiting scroll shaft 1a and the fixed scroll shaft 2a, or in other words, the semi-circular radius.

On the other hand, the wrap 15 of the orbiting scroll 1# extends 180° spirally inwardly relative to the wrap 10 on the fixed scroll side, and its starting end 15a is connected to the scroll groove starting end 10a.
As a result of approaching or turning the side semicircular groove 20a,
When the orbiting scroll l is rotated around the fixed scroll shaft 1a, the wrap end 1 on the orbiting scroll side
5a comes into sliding contact along the semicircular groove 20a, allowing smooth sliding movement.

Conversely, by adopting the above configuration, it can be said that the inner circumferential end of the wrap was able to extend 180'' to the discharge lower, and as a result, the closed space 30 is closed until the wrap end 15a reaches the discharge lower artificial end. 180 of the discharge lower.
°Compared to a conventional scroll compressor in which the final compression chamber is opened at the front, the final compression chamber can be reduced by 24% in volume and 33% in seal length, resulting in compression efficiency. will improve.

In the above embodiment, since the discharge lower is formed in the five semicircular grooves 20a, when the wrap end 15a reaches the discharge lower artificial end, more specifically, the wrap end 15a is formed in the semicircular groove 20a. There is a problem in that the final compression chamber 30 is opened before the final compression chamber 30 is reached.

Therefore, in FIG. 2, a discharge lower is bored in the bearing 5 portion on the back side of the semicircular groove 20a, and
) A conduction path 31 is formed along the circumferential surface of the bearing 5 to communicate with the knee discharge lower.

According to this configuration, the final compression chamber 30 is not opened until the wrap end 1.5a approaches the peripheral surface of the bearing 5, so the volume ratio is 11% and the seal length is 24% compared to the above embodiment. It was confirmed that the final compression chamber could be reduced by 50%, and the waste compression efficiency was improved.

, - In this embodiment, the wrap outer peripheral end 10b side of the fixed scroll also extends a 180° spiral, and when it coincides with the wrap peripheral end 1.5b of the orbiting scroll, the It is possible to enlarge the suction space 33, which is a sealed space for the wraps, and it is sufficient to provide one suction port 8 in the overlap area of the wraps 10b/1.5b on the fixed scroll 2 side.
Thereby, the above-mentioned effects of the present invention can be smoothly achieved.
5. "Effects" As described above, according to the present invention, suction efficiency and high compression can be achieved on the suction side without achieving device miniaturization, and on the discharge side, discharge efficiency and high compression can be achieved. In addition to making compression possible, it is also possible to improve the sealing performance between the wraps and the compression efficiency.

It has various effects such as

Although the function and structure of the scroll compressor have been described, the present invention is not limited to this, and can also be applied to expanders and pumping machines.

[Brief explanation of drawings]

FIG. 3 is an overall sectional view of a twin scroll compressor to which the present invention is applied, and FIGS. 1 and 2 are schematic diagrams showing the shape of the wrap and its arrangement according to an embodiment of the present invention.

Claims (1)

[Scope of Claims] 1) Consisting of one orbiting scroll having a spiral wrap formed on at least one surface in the axial direction, and one or more fixed scrolls having one spiral wrap that fits into the wrap of the orbiting scroll, In the scroll fluid machine in which the orbiting scroll is configured to be able to revolve without rotating, the inner circumferential end and/or outer circumferential end of one side wrap that is fitted facing each other extends approximately 180° compared to the circumferential end of the other side wrap. set it up,
A scroll type fluid machine characterized in that the circumferential ends of both wraps are configured to be substantially coincident with each other during the orbiting motion of the scroll 2) An orbiting scroll having a spiral wrap formed on at least one surface in the axial direction, and the orbiting scroll. In a scroll fluid machine comprising one or more fixed scrolls each having one helical wrap that fits into the wrap of the orbiting scroll, the orbiting scroll is configured to be able to revolve around itself without rotating, wherein the inner circumferential end of the wrap on the orbiting scroll side is at least It is extended to the vicinity of the discharge port provided on the peripheral edge of the fixed wrap, and
Claim 1) wherein the peripheral wall surface on the center side of the other side scroll that faces the extended peripheral end of the wrap is formed in a semicircular shape, and the wrap end surface is configured to be substantially slidable along the peripheral wall surface of the other side scroll. Scroll type fluid machine according to claim 1) Scroll type fluid machine according to claim 1) wherein the radius of the semicircular shape of the peripheral wall surface is set to be substantially the same as the eccentricity of the orbiting scroll shaft and the fixed scroll shaft 4) The semicircle Scroll type fluid machine according to claim 1, wherein the discharge port is formed on the inner side of the center side circumferential wall surface of the other side scroll formed in the shape of the other side through a conduction path.