JPH08226392A - Fluid compressor - Google Patents

Abstract

(57) [Abstract] [Purpose] Improving compression performance by achieving both reduction of flow loss and reduction of sliding loss of the rotating shaft, despite the fact that the length of the suction guide path for the fluid to be compressed is long. And a fluid compressor that contributes to weight reduction of the rotating body and the compressor. A cylinder 4 whose both ends are rotatably supported by bearings, and a shaft 10 which is eccentrically supported by the bearings.
a, 10b and the main body 1 eccentrically arranged in the cylinder
0c, a spiral groove 11 provided on the peripheral surface of the main body, and a blade fitted in the groove so as to be freely inserted and removed.
A cylinder 12, a compression chamber 13 formed in the cylinder, and an Oldham mechanism 22 for transmitting the rotational force of the cylinder to the rotating body. The piston body has a large-diameter hollow portion 18, and the piston shaft has a large-diameter hollow portion. A small-diameter hollow portion 17 communicating with the small-diameter hollow portion is provided, and a refrigerant gas is introduced from the small-diameter hollow portion and guided to the compression chamber on the suction portion side through the large-diameter hollow portion.
Was formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid compressor for compressing a refrigerant of a refrigeration cycle, for example.

[0002]

Fluid compressors are known. In this case, a cylinder and a piston are eccentrically arranged in a closed case. A spiral groove having a pitch gradually reduced from one end side to the other end side is formed in the piston, and a spiral blade is fitted into the piston so as to be freely inserted and removed.

The space between the cylinder and piston is
The blade is divided into a plurality of blades, and a compression chamber whose volume is gradually reduced is formed in the cylinder from the one end side to the other end side.

The rotational force of the cylinder is transmitted to the piston through the transmission mechanism, and the cylinder and the piston rotate synchronously at a relative peripheral speed while maintaining the positional relationship. With these rotations, the blade is projected and retracted in the radial direction of the piston.

For example, if the refrigerant gas in the refrigeration cycle is
Sucked into the cylinder from the suction pipe through the suction passage,
From the compression chamber located on the most suction side of each compression chamber,
It is gradually transferred to the compression chamber located closest to the discharge side and gradually compressed.

When reaching the compression chamber on the most discharge side, the pressure rises to a predetermined pressure, and once through the discharge passage, the closed case 1
It will be guided inside. Then, the filled high-pressure gas is introduced into the refrigeration cycle from the discharge pipe connected to the closed case.

[0007]

There is a fluid compressor of the type in which the piston has a suction guide passage for guiding the refrigerant gas to the compression chamber closest to the suction side. The suction guide passage is composed of a hollow portion provided along the axial direction of the piston.

[0008] To explain further, the piston has shaft portions axially supported by bearings at both end portions thereof, and a main body portion is provided between the shaft portions. A spiral groove is provided on the peripheral surface of the main body, and a blade is fitted therein so that the blade can move in and out freely.

The hollow portion is provided from one end surface to the other end surface of the piston, that is, through the piston from one shaft portion to the other shaft portion through the main body portion. Then, the hollow portion and the compression chamber closest to the suction side are communicated with each other by the auxiliary guide passage.

In such a compression mechanism, the path through which the refrigerant gas introduced into the closed case is guided to the compression chamber closest to the suction side becomes long. Therefore, the diameter of the suction guide passage is increased to reduce the flow loss of the suction gas and prevent the compression performance from being deteriorated.

However, since the diameter dimension of the piston shaft portion is set according to the diameter dimension of the suction guide passage which is a hollow portion penetrating therethrough, it depends on the diameter dimension of the suction guide passage set to be large. Inevitably grows.

That is, since the diameter of the piston shaft portion is increased, the sliding loss of the piston shaft portion with respect to the bearing member is increased, and the input of the electric motor portion that rotationally drives the piston and the cylinder is increased. However, there is a problem that efficiency is lowered.

The diameter of the piston shaft is large,
Since the diameter of the main body portion is set so as to accommodate it, it becomes large. This piston has a large weight since it is molded from a casting, which hinders the weight reduction of the compressor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to reduce the flow loss and to reduce the rotation shaft shaft portion in spite of the long suction guide path length of the fluid to be compressed. An object of the present invention is to provide a fluid compressor that contributes to weight reduction of a rotary body and a compressor while achieving reduction in sliding loss and improvement of compression performance.

[0015]

In order to achieve the above object, the fluid compressor of the present invention comprises, as claim 1, a cylinder whose both ends are rotatably supported by bearings, and the bearing. A rotary body having eccentrically supported shaft portions at both end portions and a main body portion eccentrically disposed in the cylinder between the shaft portions, and a shaft provided on the peripheral surface of the main body portion of the rotary body. A spiral groove formed in the circumferential surface at a gradually decreasing pitch along the direction, a spiral blade fitted in the groove of the rotating body so as to be able to move in and out, and formed in the cylinder, A plurality of compression chambers, which are gradually divided into smaller volumes by the blades, and the cylinder and the rotating body, are synchronously rotated at a relative peripheral speed, and are compressed into the compression chambers. Compress the fluid while gradually transferring it to the compression chamber In a fluid compressor provided with a rotational force transmission mechanism for letting out, a large-diameter hollow portion provided in the main body of the rotating body and a small-diameter hollow portion provided in a shaft portion of the rotating body communicating with the large-diameter hollow portion. And a suction guide passage for introducing the fluid to be compressed from the small-diameter hollow portion and guiding the fluid to the compression chamber on the suction portion side through the large-diameter hollow portion.

A second aspect of the present invention is characterized in that the central axes of the large-diameter hollow portion and the small-diameter hollow portion according to the first aspect coincide with the central axis of the rotating body. As claim 3, claim 1
Further, a tapered hollow portion having a gradually increasing diameter dimension is provided between the small-diameter hollow portion and the large-diameter hollow portion according to claim 2.

As claim 4, claim 1 and claim 2
In any one of the above, only the portion of the large-diameter hollow portion near the compression chamber suction portion is made smaller than the diameter dimension of the other portion.

Claims 1 and 2 are defined as Claim 5.
The suction guide tube protruding into the large-diameter hollow portion is fitted into the compression chamber suction portion of the large-diameter hollow portion.

Claims 1 to 5 are defined as claim 6.
Any one of the spiral groove provided in the rotating body and the blade fitted in the spiral groove so as to be able to move in and out are provided in a pair along the axial direction.

[0020]

Function: The diameter of the hollow portion provided in the body of the rotating body is set larger than the diameter of the hollow portion provided in the shaft portion of the rotating body, and the diameter of the hollow portion is made large as a whole to allow the flow of the fluid to be compressed. The loss is reduced, the diameter of the shaft portion of the rotating body is kept small, the sliding loss with respect to the bearing is reduced, and the rotating body is made lighter.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the sealed case 1 is arranged with its axial direction oriented horizontally. The compression mechanism portion 2 and the electric motor portion 3 are housed in the closed case 1.

The compression mechanism section 2 has a cylinder 4 made of a hollow cylinder whose both ends are open, and a rotor 5 is fitted on the outer peripheral surface of this cylinder. A stator 6 is fitted on the inner peripheral surface of the case body 1a of the hermetically sealed case 1, and the rotor 5 constitutes the electric motor section 3. The electric motor section 3 is a rotary drive source for rotationally driving the cylinder 4.

Metal bearings 7, 7 are press-fitted and fixed in the openings of both ends of the cylinder 4, and these bearings are loosely inserted into pivot shaft portions 8a, 9a provided in the main bearing member 8 and the sub bearing member 9, respectively. And is rotatably supported together with the bearing.

The main bearing member 8 and the sub bearing member 9 are formed by connecting the pivot shaft portions 8a, 9a and the flange portions 8b, 9b integrally provided at the base end portion of the pivot shaft portions. The pivot hole portion 8 extends over the flange portion and the pivot shaft portion.
c and 9c are provided.

The pivot shaft portions 8a and 9a and the flange portions 8b and 9
The central axis Sa of b and the central axis Sa of the cylinder 4 and the closed case 1 coincide with each other. The central axis Sb of the pivot hole portions 8c and 9c is provided eccentric with respect to the central axis Sa by an eccentric amount e.

In the cylinder 4, a piston 10 as a rotating body is eccentrically arranged. This piston 10
It is composed of shaft portions 10a and 10b formed at both ends and a main body portion 10c formed between these shaft portions.

The shaft portions 10a and 10b are loosely inserted into the pivot support holes 8c and 9c of the main and auxiliary bearing members 8 and 9 and are rotatably supported. Since the pivot holes 8c and 9c are provided eccentrically, a part of the peripheral wall of the piston body 10c along the axial direction is rolled and accommodated in a part of the inner peripheral wall of the cylinder 4 along the axial direction.

Further, on the peripheral surface of the piston body 10c,
In the figure, a pair of left and right spiral grooves 11 and 1 each having a pitch gradually reduced from the axial middle portion to both end portions.
1 is provided. Then, the spiral blades 12 and 12 (shown by alternate long and short dash lines) are fitted in the grooves 11 and 11 so as to be freely inserted and removed.

Therefore, the space between the cylinder 4 and the piston 10 is divided into a plurality of chambers by the blades 12 and 12 on the left and right sides of the intermediate portion. Inside the cylinder 4, a plurality of compression chambers 13 ..., 13 ... whose volume is gradually reduced from the middle part of the cylinder to both end sides, that is, from the suction part side to the discharge part side are formed.

The flange portion 8b of the main bearing member 8 is attached and fixed to the inner wall of the closed case 1. The flange portion 9b of the sub bearing 9 is supported by a support plate 14 provided in parallel with the end surface of the closed case 1 at a predetermined distance.

A suction pipe 15 communicating with a refrigeration cycle device (not shown) is connected to the sealed case 1 so as to communicate with the main bearing tool pivot hole 8c. The piston 1 is connected to the suction pipe 15 and the pivot hole 8c.
At 0, a gas suction guide passage 16 which is a hollow portion is provided.

The gas suction guide passage 16 will be further described. This is provided with hollow portions 17 and 17 having a small diameter dimension φda provided from the end faces of the shaft portions 10a and 10b on both sides to the end portion of the main body portion 10c, and the main body. A hollow portion 18 having a large diameter dimension φdb provided across both ends of the portion 10c is provided in series. That is, φda <φdb.

The small-diameter hollow portions 17, 17 and the large-diameter hollow portion 18 have a common central axis Sb, and also coincide with the central axis of the piston 10 itself. Small-diameter hollow part 1 on the main bearing 8 side
7 is communicated with the suction pipe 15 through the pivot hole 8c, and the small-diameter hollow portion 17 on the side of the auxiliary bearing 9 is closed at its open end by a closing cover 19 provided on the auxiliary bearing 9.

A pair of vertical holes 20, 20 are provided in the middle portion of the large-diameter hollow portion 18 in a direction orthogonal to each other, and open on the peripheral surface of the piston 10. This opening position corresponds to the space between the pair of left and right blades 12, 12.

Guide guide holes 21 and 21 are provided at both ends of the cylinder 5, respectively. These lead-out guide holes 21
Connects the compression chambers 13 at both ends with the inside of the closed case 1. The cylinder 4 and the piston shaft portion 1 on the side of the sub bearing 9
An Oldham mechanism 22 as a mechanism for transmitting the rotational force of the cylinder to the piston 10 is provided between the cylinders 0 and 0b.

A lead-out pipe 23 is connected to a side portion of the closed case 1, and the pipe is connected to an external refrigeration cycle device (not shown). An oil reservoir 24 for collecting lubricating oil is formed on the inner bottom of the closed case 1.

The support plate 14 is provided with an oil guide notch 14a located in the lubricating oil of the oil sump 24,
In addition, a gas guide hole 14b is provided above the oil level.

In the lubricating oil of the oil sump portion 24, oil suction passages 25a, 25 which are integrally projected on the main and auxiliary bearing members 8, 9 are provided.
b is immersed. The upper ends of these oil suction passages 25a, 25b are oil supply pump parts 26a, 26b made of spiral blades wound around the piston shaft parts 10a, 10b.
Communicate with

As described above, the oil suction passages 25a and 25b are provided in the bearings 8 and 9 and the piston shaft portions 10a and 10b.
Further, an oil supply mechanism including oil supply pump parts 26a, 26b and the like is provided, and as the piston 10 rotates, the lubricating oil of the oil sump part 24 is sucked up and oil is supplied to each sliding part constituting the compression mechanism part 2. Has become.

A compressor constructed in this way,
The rotor 5 and the cylinder 4 are energized as the motor part 3 is energized.
And rotate together. The rotational force of the cylinder 4 is transmitted to the piston 10 via the Oldham mechanism 22.

The piston 10 is pivotally supported at an eccentric position with respect to the cylinder 4, but the action of the Oldham mechanism 22 causes the cylinder 4 and the piston 10 to move at a relative peripheral speed due to the difference in radius between them. In addition, they rotate synchronously while maintaining their mutual positional relationship.

With the rotation of the cylinder 4 and the piston 10, the pair of blades 12 and 12 simultaneously move in and out of the respective grooves, and the piston 10 is projected and retracted in the radial direction. A compressed gas, for example, a refrigerant gas in a refrigeration cycle is sucked from the suction pipe 15 and guided to the gas suction guide passage 16 through a pivot hole 8c formed in the main bearing member 8.

That is, the refrigerant gas is the piston shaft portion 10a.
Is guided to the large-diameter hollow portion 18 through the small-diameter hollow portion 17 provided in the
Is also full. Then, it is sucked into the compression chambers 13 and 13 formed in approximately the middle portion of the cylinder 4 through the vertical holes 20 and 20 communicating with the large-diameter hollow portion 18.

The substantially middle portion of these cylinders 5 is the compression chamber located on the most suction side of the compression chambers 13 formed on both the left and right sides, and the left and right ends on the most delivery side from this. Are sequentially transferred to the compression chamber.

The refrigerant gas is gradually compressed while being sequentially transferred through the compression chambers 13, 13. Then, when it is transferred to the compression chambers 13, 13 on the most outflow side of both left and right ends, the pressure rises to a predetermined pressure and becomes high.

The high-pressure gas is introduced into the closed case 1 from the compression chambers 13 and 13 through the guide holes 21 and 21 provided at both ends of the cylinder 4, and fills the space. Then, the high-pressure gas is guided to the end portion side of the case 1 through the gas guide hole 14b provided in the support plate 14, and is discharged from the discharge pipe 23 to the external refrigeration cycle device.

In the compressor having such an operation, particularly in the main body portion 10c occupying most of the piston 10, the diameter dimension φdb of the hollow portion 18 provided therein is made large, and the shaft portions 10a at the left and right ends of the piston are provided. , 10b, the diameter dimension φda of the hollow portions 17, 17 is made small.

With the above settings, these hollow portions 17,
The overall diameter dimension of the gas suction guide passage 16 formed by 18 can be made large, and a reduction in gas flow loss can be obtained. On the other hand, since the diameter dimension φda of the hollow portion 17 of the piston shaft portions 10a and 10b is reduced, the shaft portion 1
The diameter of 0a, 10b itself can be reduced,
Sliding loss with respect to the main and auxiliary bearing members 8 and 9 is reduced.

Further, since the central axis Sb of the piston 10 and the central axes Sb of the small-diameter hollow portion 17 and the large-diameter hollow portion 18 forming the gas suction guide passage 16 are aligned with each other, the piston 1
The rotation balance of 0 is improved, and vibration and noise can be further reduced.

The volume of the hollow portion of the piston 10 becomes large as a whole, and the weight of the piston becomes lighter. This leads to a reduction in the weight of the compressor itself and also a reduction in the weight of the device equipped with the compressor.

The gas suction guide passage 16 in the above embodiment connects the small-diameter hollow portions 17, 17 provided in the piston shaft portions 10a, 10b and the large-diameter hollow portion 18 provided in the piston main body portion 10c. Further, the continuous portion of these hollow portions is formed in a step shape, but the present invention is not limited to this.

For example, the gas suction guide passage 16A as shown in FIG. 2 may be used. Hereinafter, the gas suction guide path 16A will be described in detail. Since all the other components are the same as those described above with reference to FIG. 1, the same reference numerals are given and a new description will be omitted.

The piston shafts 10a and 10b are provided with a small-diameter hollow portion 17, while the piston main body portion 10c is provided with a large-diameter hollow portion 18 leaving both end portions. The diameter dimensions of these hollow portions 17 and 18 are the same as those described above,
φda and φdb.

A tapered hollow portion 30 is provided between the small-diameter hollow portion 17 and the large-diameter hollow portion 18. In other words, one end diameter dimension φda of the tapered hollow portion 30 coincides with the small-diameter hollow portion 17, and the other end diameter dimension φdb is large-diameter hollow portion 1.
8 corresponds, and the small diameter hollow portion and the large diameter hollow portion communicate with each other by this hollow portion.

With such a gas suction guide passage 16A, the gas is guided from the small-diameter hollow portion 17 to the large-diameter hollow portion 18 through the tapered hollow portion 30 having a gradually increasing diameter, and The flow is very smooth and the flow losses are lower.

Gas suction guide passage 16B as shown in FIG.
It may be. Hereinafter, the gas suction guide path 16B will be described in detail. Since all the other components are the same as those described above with reference to FIG. 1, the same reference numerals are given and a new description will be omitted.

A small diameter hollow portion 17 is provided on the piston shaft portions 10a and 10b. The piston body portion 10c is provided with a pair of large-diameter hollow portions 18 and 18 on the left and right, leaving a connection portion with the vertical holes 20 and 20 provided at substantially the middle portion thereof. The diameters of these hollow portions 17 and 18 are φda and φdb, which are the same as those described above.

And, here, only the connecting portion between the large-diameter hollow portions 18, 18 and the vertical holes 20, 20 is the small-diameter portion 2.
8 are provided. The diameter of the small diameter portion 28 is also φda
May be

Therefore, the gas suction guide passage 16B is provided.
Is a small-diameter portion 28 in the middle and large-diameter hollow portions 1 on the left and right sides
8 and 18, and small-diameter hollow parts 1 on both the left and right sides of these
7, 17 are integrally connected.

As described above, in the piston body 10c, not only the large-diameter hollow portion 18 of φdb as described above, but only the portion near the vertical holes 20, 20 which is the suction portion of the compression chamber 13 has the diameter dimension φda. The feature is that the small diameter portion 28 is provided.

With the rotation of the piston 10, however, the refrigerant gas is sucked from the suction pipe 15 into the gas suction guide passage 16B. Depending on the operating state, liquid refrigerant may be mixed in the refrigerant gas. When this liquid refrigerant is introduced into the compression chamber 13 as it is, the liquid refrigerant is not compressed and the compression efficiency is reduced.

According to the configuration of the figure, even if the liquid refrigerant is mixed and guided from the small-diameter hollow portion 17 of the gas suction guide passage 16B to the large-diameter hollow portion 18, the vertical holes 20 and 20 are formed.
Since the small-diameter portion 28 is provided between and, the flow of the liquid refrigerant is blocked.

That is, the liquid refrigerant introduced into the large-diameter hollow portion 18 is adhered to the peripheral wall of the hollow portion due to the centrifugal force caused by the rotation of the piston 10 and stays there. Large hollow 18
If the vertical hole 20 is opened in the peripheral wall of the liquid refrigerant, the liquid refrigerant is guided to the vertical hole as it is, but since the small diameter portion 28 is connected to the large diameter hollow portion 18, the liquid refrigerant is large diameter hollow. It is not guided to the small diameter portion 28 which is stopped at the portion 18 and whose diameter dimension is smaller than this.

After all, even if the liquid refrigerant is mixed with the gas refrigerant and is sucked into the compressor, the compression chamber 1 on the suction portion side.
Only the gas refrigerant is guided to 3, and the introduction of the liquid refrigerant is blocked, so that the compression efficiency can be improved.

Gas suction guide passage 16C as shown in FIG.
It may be. Hereinafter, the gas suction guide path 16C will be described in detail. Since all the other components are the same as those described above with reference to FIG. 1, the same reference numerals are given and a new description will be omitted.

The structure of the gas suction guide passage 16C is basically the same as that shown in FIG. That is, the piston shaft portions 10a and 10b are provided with small-diameter hollow portions 17 and 17, and the piston body portion 10c is provided with a large-diameter hollow portion 18. The diameter of these hollow portions 17 and 18 is φda.
, Φdb.

The feature here is that the suction guide pipes 35, 35 are fitted and inserted into the pair of vertical holes 20, 20 provided at substantially the middle portion of the large-diameter hollow portion 18. One end portion of the suction guide tube 35 is aligned with or inside the peripheral surface of the piston body portion 10c. At least, it should not protrude beyond the peripheral surface of the main body portion 10c. The other end projects into the large-diameter hollow portion 18. By setting the protrusion size from the peripheral wall of the large-diameter hollow portion 18, the mutual distance between the front end portions of the suction guide tubes 35, 35 is set to da.

With this structure, the same effect as that shown in FIG. 3 can be obtained. That is, even if the liquid refrigerant is mixed, the gas suction guide passage 1
Even if it is guided from the small-diameter hollow portion 17 of 6C to the large-diameter hollow portion 18, it adheres to the peripheral wall of the large-diameter hollow portion 18 and stays there due to the centrifugal force accompanying the rotation of the piston 10.

Since the suction guide pipe 35 projects into the large-diameter hollow portion 18, the liquid refrigerant stays in the large-diameter hollow portion 18 and is not guided to the suction guide pipe 35. After all, only the gas refrigerant is guided to the compression chamber 13 on the suction portion side, the introduction of the liquid refrigerant is blocked, and the compression efficiency can be improved.

The piston is manufactured as shown in FIG. First, a pair of piston dividers 10A and 10A are manufactured as shown in FIG. In each of the dividers 10A and 10A, shaft portions 10a and 10b and main body portions 10ca and 10cb having a half length in the axial direction are integrally connected.

The shaft portions 10a and 10b have small-diameter hollow portions 17,
17, and large-diameter hollow portions 18a and 18b are provided in the main body portions 10ca and 10cb. Mutual body 10c
A chamfered portion 40, 40 is provided on the outer peripheral portion of the end surface of a, 10cb.

As shown in FIG. 7B, the chamfered end faces of the piston dividers 10A, 10A are butted against each other and positioned and fixed. Of course,
No slight misalignment is recognized.

Then, for example, welding is performed along the chamfered portions 40, 40. Piston divider 10A, 10A
The two are welded together and integrated. However, the solidified beat D is raised in the chamfered portions 40, 40 that are abutted with each other.

As shown in FIG. 7C, the beat D is cut to even out the peripheral surface of the main body 10c. Therefore, as described above, the piston 10 is formed by integrally connecting the shaft portions 10a and 10b and the main body portion 10c and forming the small diameter hollow portion 17 and the large diameter hollow portion 18 along the central axis Sb. Is obtained.

By adopting such a manufacturing method, the piston 10 having a small diameter hollow portion 17 at both ends and a large diameter hollow portion 18 between the small diameter hollow portions, that is, a piston 10 having a special shape is provided. Since it can be easily obtained, workability can be improved.

In all of the above description, the cylinder 4 and the piston 10 are provided with a pair of left and right blades 12 and 12 and compression chambers 13 ...
Although the so-called twin type compressor has been described, the present invention is not limited to this. It also applies to so-called single type compressors, which have one set of blades and compression chambers for cylinders and pistons. Needless to say, the structure of this type of compressor is the same as that described above except that the blade and the compression chamber are one set.

Of course, the application of the fluid compressor of the present invention is not limited to the refrigeration cycle. The present invention can be variously modified without departing from the scope of the invention.

[0078]

As described above, the present invention provides claim 1.
In the body of the rotating body, a hollow portion having a diameter larger than the diameter of the shaft portion of the rotating body is provided, and since these hollow portions are used as the gas suction guide path, despite the fact that the path of this suction guide path is long, Almost most of it can be formed from a large-diameter hollow portion, and flow loss can be reduced. The diameter of the shaft portion of the rotating body can be set small, and sliding loss with respect to the bearing can be reduced. The weight of the rotating body can be further reduced and made lighter,
All have the effect of being connected to the improvement of compression performance.

In the second aspect, since the central axis of each hollow portion is aligned with the central axis of the rotating body, the rotational balance of the rotating body is improved, and the vibration and noise can be reduced. In the third aspect, since the tapered hollow portion whose diameter size gradually increases is provided between the small-diameter hollow portion and the large-diameter hollow portion, the fluid to be compressed is smoothly guided to lower the flow loss. Can be suppressed.

According to the present invention, only the portion of the large-diameter hollow portion in the vicinity of the suction portion of the compression chamber is made smaller in diameter than the other portions. Therefore, even if a liquid phase is mixed in the fluid to be compressed, It is possible to prevent suction into the compression chamber and improve compression efficiency.

According to the present invention, since the suction guide tube protruding into the large-diameter hollow portion is fitted into the suction portion of the compression chamber, even if the fluid to be compressed contains a liquid phase, this liquid phase is introduced into the compression chamber. It is possible to prevent suction and improve compression efficiency.

According to the sixth aspect of the present invention, since the spiral groove provided in the rotating body and the blade fitted in the groove so as to freely move in and out are provided in a pair, which is a so-called twin type, the axial length of the rotating body is increased. However, the increase in weight can be suppressed as much as possible by setting the hollow portion, and in addition, the effects of claims 1 to 5 can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a fluid compressor according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a fluid compressor according to another embodiment.

FIG. 3 is a vertical sectional view of a fluid compressor according to another embodiment.

FIG. 4 is a vertical cross-sectional view of a fluid compressor according to another embodiment.

5A to 5C are views for sequentially explaining a manufacturing process of a piston that is a rotating body.

[Explanation of symbols]

4 ... Cylinder, 10 ... Rotating body (piston), 10a, 1
0b ... Shaft part, 10c ... Main body part, 13 ... Compression chamber, 18 ... Large diameter hollow part, 17 ... Small diameter hollow part, 16, 16A-16C ...
Suction guide passage, 30 ... Tapered hollow portion, 28 ... Small diameter portion,
35 ... Suction guide tube.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshinori Sone 70 Yanagicho, Sachi-ku, Kawasaki-shi, Kanagawa Toshiba Yanagimachi factory (72) Takashi Motokatsu 70 Yanagi-cho, Sachi-ku, Kawasaki, Kanagawa Toshiba Corporation Inside the Yanagimachi Plant (72) Inventor Teruhisa Tsunekawa 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Inside Toshiba Abu-E Co., Ltd.

Claims (6)

[Claims] 1. A cylinder, both ends of which are rotatably supported by bearings, and a shaft portion eccentrically supported by the bearing member is provided at both ends, and a cylinder is provided between the shaft portions in the cylinder. A rotating body having an eccentrically arranged main body, a spiral groove provided on the peripheral surface of the main body of the rotating body, and formed on the peripheral surface along the axial direction at a gradually decreasing pitch, A spiral blade that is fitted in and out of the groove of the body, a plurality of compression chambers that are formed in the cylinder and are divided into smaller volumes by the blade, the cylinder and the rotation A fluid provided with a rotational force transmitting mechanism for rotating the body at a relative peripheral speed and synchronously, and for compressing and discharging the compressed fluid sucked into the compression chamber while gradually transferring it to the compression chamber. In the compressor, the main body of the rotating body A large-diameter hollow portion is provided, and a small-diameter hollow portion provided on the shaft portion of the rotating body that communicates with the large-diameter hollow portion is provided. A fluid compressor characterized in that a suction guide path is formed through which the suction guide path is guided to the compression chamber on the suction section side. 2. The central axes of the large diameter hollow portion and the small diameter hollow portion are
The fluid compressor according to claim 1, wherein the fluid compressor coincides with a central axis of the rotating body. 3. A taper-shaped hollow portion whose diameter dimension gradually increases is provided between the small-diameter hollow portion and the large-diameter hollow portion. The fluid compressor according to. 4. The fluid compressor according to claim 1, wherein only the portion of the large-diameter hollow portion near the suction portion of the compression chamber is made smaller than the diameter dimension of the other portion. . 5. The fluid according to claim 1, wherein a suction guide tube projecting into the large-diameter hollow portion is fitted in the compression chamber suction portion of the large-diameter hollow portion. Compressor. 6. The spiral groove provided in the rotating body and a pair of blades fitted in the spiral groove so as to freely move in and out are provided as a pair along the axial direction. The fluid compressor according to claim 1.