JP2001295781A - Fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid machine capable of improving a compression performance and high reliability regardless of a compression ratio by suppressing gas leakage to the minimum in a place where a blade is fully inserted into a spiral groove even if the compression ratio is in a high condition. SOLUTION: The fluid machine is provided with a helical blade type operating mechanism 3 having a cylinder 5, a roller 11 eccentrically disposed in the cylinder, a spiral groove 14 disposed along a circumferential surface of the roller, and a spiral blade 15 which is fitted to the spiral groove freely to go in an out, and for sectioning a space between a cylinder and it in a plurality of an operation chambers 16. A release groove is disposed on a high pressure side wall surface of a spiral groove to release pressure to the operation chamber of a high pressure side when prescribed pressure in the operation chamber extends a pressure in the high pressure side operation chamber. When a width size of the release groove is set to X, and a width size of the spiral groove is set to t, a ratio (X/t) between the release groove width size X and the spiral groove width size t, is set equally to 0.6 or set to be not more than a value (X/t <=0.6).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid machine, for example, a helical blade type compressor used in a refrigeration cycle apparatus.

[0002]

2. Description of the Related Art Recently, a helical blade type compressor, also called a fluid compressor, has been proposed. In this configuration, a roller, which is a rotating body, is eccentrically arranged in a cylinder connected to a rotary drive source, and is driven to rotate in synchronization with the cylinder.
A spiral groove is provided on the peripheral surface of the roller, and the blade is wound so as to be able to enter and exit freely.

A compression chamber, which is a working chamber, is formed between the blade, the peripheral surface of the roller and the inner peripheral surface of the cylinder, and a refrigerant gas, which is a working fluid, is sucked into one end of the compression chamber. It is designed to be compressed while being gradually transferred.

[0004]

In this type of compressor, the compression ratio is determined by the spiral shape.
In an operation in which the compression ratio is low, such as at the time of low rotation or start-up, which is a region outside the designed compression ratio, an over-compression state is likely to occur, and at that time, the compression performance is significantly reduced.

[0005] In order to solve such a problem, a fluid compressor disclosed in Japanese Patent Application Laid-Open No. 10-47272 has been proposed.
When the pressure in the compression process exceeds a predetermined pressure, a release passage is provided in the blade that separates the compression chamber to release the pressure into the working chamber on the discharge side. I have sex.

[0006] However, the provision of the release passage has a problem particularly in an operation state where the compression ratio is high. That is, at a position where the blades all enter the spiral groove and do not protrude from the groove at all, a seal surface is formed on the inner periphery of the cylinder where the roller peripheral surface is in line contact along the axial direction. Gas leaks from the high pressure side to the low pressure side through the passage.

In addition, since the spiral groove and the blade are designed to have a clearance between each other, gas leakage also occurs from a clearance portion communicating with the release flow path, and the compression performance may be further reduced. is there.

The present invention has been made based on the above circumstances, and an object of the present invention is to achieve a gas leak at a position where all the blades enter the spiral groove even when the compression ratio is high. It is an object of the present invention to provide a fluid machine which can improve compression performance and obtain high reliability regardless of the compression ratio.

[0009]

According to a first aspect of the present invention, there is provided a fluid machine having a cylinder, a roller disposed eccentrically in the cylinder, and a roller provided along a peripheral surface of the roller. In a fluid machine having a helical blade type operating mechanism having a spiral groove formed therein, and a spiral blade partitioning a space between a cylinder and a plurality of working chambers so as to be freely inserted into and retracted from the spiral groove, When the pressure of a predetermined working chamber exceeds the pressure of an adjacent high-pressure working chamber, a release groove for releasing the pressure to the high-pressure working chamber is provided on the high-pressure side wall surface of the spiral groove, and the width of the release groove is provided. Assuming that the dimension is X and the width of the spiral groove is t, the ratio of the release groove width X to the spiral groove width t (X / t)
Is set equal to or less than 0.6 (X / t ≦ 0.6).

According to a second aspect of the present invention, in a fluid machine having a helical blade type operation mechanism, when the width dimension of the release groove is X and the inner circumference of the cylinder is Dc × π, the release groove width dimension X and the cylinder internal diameter are set to Xc. Ratio to circumference Dc × π (X /
Dc × π) is equal to or less than 0.02 (X / Dc
× π ≦ 0.02).

According to a third aspect of the present invention, in a fluid machine having a helical blade type operating mechanism, when the sectional area of the release groove is s and the clearance sectional area between the spiral groove and the blade is K, the sectional area of the release groove is The ratio (s / K) of s to the clearance cross-sectional area K between the spiral groove and the blade is expressed by:
It is characterized by being set equal to or less than 2.0 (s / K ≦ 2.0).

According to a fourth aspect of the present invention, in a fluid machine having a helical blade type operating mechanism, when the width of the release groove is X and the width of the spiral groove is t, the release groove width X and the spiral groove width are set. The ratio (X / t) to the dimension t is 0.6
(X / t ≦ 0.6) and when the inner circumference of the cylinder is Dc × π, the release groove width dimension X
And the ratio (X / Dc × π) of the cylinder inner circumference Dc × π to 0.
02 or less (X / Dc × π ≦ 0.02), the sectional area of the release groove is s, and the sectional area of clearance between the spiral groove and the blade is K, the sectional area of the release groove The ratio (s / K) of s to the clearance cross-sectional area K between the spiral groove and the blade is equal to or less than 2.0 (s / K).
/K≦2.0).

By adopting a means for solving such a problem, even when the compression ratio is high, gas leakage at a position where all the blades enter the spiral groove is suppressed to a minimum. Regardless of the compression ratio, improved compression performance and high reliability can be obtained.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. A fluid compressor, which is a fluid machine disclosed herein, is used for, for example, a refrigeration cycle of an air conditioner. It is.

As shown in FIG. 1, in a closed case 1,
In the drawing, a compression mechanism 3 where a right side portion is a helical blade type operation mechanism portion and a left side portion as an electric motor portion 4 are accommodated, respectively, around a substantially central portion in the axial direction of the sealed case 1.

The compression mechanism 3 is a hollow cylindrical body whose both ends are open, and has flanges 5a and 5
b has a cylinder 5 integrally projecting therefrom. A main bearing 6 is provided on one side (left side in the figure) of the cylinder 5.
Is mounted and fixed via the fixture 7, and the opening of the cylinder is closed. On the side surface on the other end side (the right side in the figure), a sub-bearing 8 is mounted and fixed via a fixture 7, and the opening of the cylinder is closed.

A crankshaft 9 is inserted along the axis of the main bearing 6 and the sub-bearing 8, and is rotatably supported. The crankshaft 9 not only penetrates into the cylinder 5 between the main bearing 6 and the sub-bearing 8, but also protrudes from the main bearing 6 in the left direction in FIG. Constitute.

The crankshaft 9 will be further described. The circumferential surface between the main bearing 6 and the sub-bearing 8 is provided at a position apart from each other and eccentric with the crankshaft axis a by a predetermined dimension e. The two crank portions 9a and 9b of the core b are provided integrally. The left crank portion 9a in the figure is referred to as a first crank portion, and the right crank portion 9a is referred to as a first crank portion.
b is called a 2nd crank part. Mutual crank 9a,
9b has the same predetermined width.

A counterbalance portion 9c is provided integrally with the crankshaft, adjacent to a portion on the left side of the first crank portion 9a. This counter balance unit 9c
Is eccentric to the peripheral surface portion on the opposite side via the axis from the eccentric projection direction of the first crank portion 9a. A counter balancer 10 separate from the crankshaft 9 is fitted adjacent to a further right portion of the second crank portion 9b. The counter balancer 10 is eccentric to a peripheral surface portion of the second crank portion 9b opposite to the eccentric protruding direction.

Between the crankshaft 9 and the cylinder 5, a roller 11 made of, for example, an aluminum alloy material having a specific gravity smaller than that of iron is interposed. The roller 11 is a cylindrical body having both ends opened,
The axial length corresponds to the axial length of the cylinder. A stepped bore 12 is formed in the inner periphery of the roller 11,
In particular, portions of the crankshaft 9 facing the first and second crank portions 9a and 9b have the same width as the crank portions and are rotatably slidably in contact with the outer peripheral surface. The supporting portions 12a and 12b are provided.

As a result, the axis b of the roller 11 coincides with the axis b of the first and second crank portions 9a and 9b and is eccentric with respect to the axis a of the cylinder 5 by the dimension e. become. A part of the outer peripheral wall of the roller 11 is dimensioned so as to be in rolling contact with a part of the inner peripheral wall of the cylinder 5 along the axial direction.

An Oldham mechanism 13 is provided between the end of the roller 11 on the side of the main bearing 6 and the roller 11. The Oldham mechanism 13 regulates the rotation of the roller 11. A sub bearing 8 is provided on the outer peripheral surface of the roller 11.
A spiral groove 14 having a gradually decreasing pitch is provided from the mounting end to the main bearing 6 mounting end, and a spiral blade 15 is wound around this groove so as to be able to freely enter and exit.

The blade 15 is made of a highly lubricating material such as fluorine resin, and has an inner diameter larger than the outer diameter of the roller 11. That is, blade 1
5 is forcibly fitted in the spiral groove 14 in a state where the diameter is reduced. As a result, the outer peripheral surface of the blade 15 is always elastically attached to the inner peripheral wall of the cylinder in a state where the roller 11 is incorporated in the cylinder 5 together with the roller 11. It swells and deforms so as to abut.

A sectional view of the cylinder 5 and the roller 11 taken along a radial direction shows that the roller 11 is accommodated eccentrically with respect to the cylinder 5 and a part of the peripheral surface of the roller is in rolling contact with the cylinder. Therefore, a crescent-shaped space is formed between the cylinder and the roller. Looking at the space along the axial direction, the blade 15 is wound around the spiral groove 14 of the roller 11 and the outer peripheral surface thereof is in rolling contact with the inner peripheral wall of the cylinder 5. Is divided into a plurality of spaces.

These partitioned spaces are referred to as working chambers 16. The volume of each working chamber 16 gradually decreases from the end of the sub-bearing 8 to the end of the main bearing 6 from the pitch setting of the spiral groove 14. And each working chamber 16
Are provided with a release groove 20, which will be described later.

A suction pipe 17 communicating with an evaporator constituting a refrigeration cycle (not shown) is provided at the side of the closed case 1.
Are provided to penetrate, and are connected to a connection portion 8 a provided on the sub bearing 8 inside the sealed case 1. The connecting portion 8a is provided with a concave portion 1 provided on the cylinder flange portion 5b.
9 and communicates with a buffer 21 provided on the outer peripheral surface of the end of the cylinder 11.

A discharge hole 24 is provided on a side surface of the main bearing 6.
Is provided. Through this discharge hole 24, the cylinder 5
And the roller 11 side end space and the electric motor unit 4 side space are communicated. From the setting of the pitch of the spiral groove 14,
The working chamber 16 on the side where the buffer section 21 is provided serves as the suction section A, and the working chamber 16 on the side provided with the discharge hole 24 on the opposite side serves as the discharge section B.

A first space 25 surrounded by the main bearing 6, the crankshaft 9 and the roller 11 is formed, and a second space 26 surrounded by the crankshaft 9 and the roller 11 is formed. Further, a third space 27 surrounded by the sub-bearing 8, the crankshaft 9 and the roller 11 is formed.

A guide hole 28 is provided along the axis of the crankshaft from the end surface of the crankshaft 9 on the side of the sub-bearing 8 to the middle part of the pivotal support of the main bearing 6. The open end of the guide hole 28 and the open end of the shaft pivot of the sub-bearing 8 are closed by a closing plate 30 attached to the sub-bearing end face via a fixing tool 29. The guide hole 28, the outer peripheral surface of the crankshaft 9, and the bearings 6, 8 are communicated by a plurality of gas holes 31, 32.
A gas guide hole 43 is provided on the upper side of the cylinder flange 5a in the drawing, penetrating both side surfaces.

The electric motor section 4 has a rotor 45 fitted to the rotating shaft section 9Z of the crankshaft 9 protruding from the main bearing 6, and a predetermined gap from the outer peripheral surface of the rotor. And a stator 46 fitted on the peripheral surface.

As shown in FIGS. 2 and 3, the release groove 20 is formed on a wall surface of the spiral groove 14 at a position for each turn (spiral position angle of 360 °) of the spiral groove 14 formed on the roller 11. Provided. In addition, if it explains, each release groove 20
Is a discharge section B facing each working chamber 16 and on the high pressure side.
Only on the side wall.

The release groove 20 is formed in a semicircular shape from the peripheral surface of the roller 11, and the bottom surface thereof is formed to have a very small step with the bottom surface of the spiral groove 14. It should be noted that even if the bottom surface of the release groove 20 is provided to be the same as the bottom surface of the spiral groove 14, there is no problem.

The width direction of the release groove 20 and the width direction of the spiral groove 14 are orthogonal to each other.
The width dimension of 0 is X, and the width dimension of the spiral groove 14 is t. In particular, as shown in FIG. 3, the rectangular hatched portion facing the release groove 20 represents a seal surface when all the blades 15 are pushed into the spiral groove 14 at the position of the release groove 20. The spiral groove 14
From the location where the front side of
, And the low pressure side L is from where the rear side extends in the suction part A direction.

In the fluid compressor constructed as described above, the electric motor section 4 is energized to rotate the crankshaft 9 together with the rotor 45 integrally. The torque of the crankshaft 9 is transmitted to the roller 11 via the first and second crank portions 9a and 9b.

That is, the crank portions 9a and 9b are provided eccentrically, and the inner pivot portion 12 of the roller 11 is provided here.
a and 12b are rotatably engaged with each other.
Is pushed by the crank part. Moreover, the crankshaft 9
Since the Oldham mechanism 13 provided between the roller 11 and the roller 11 regulates the rotation of the roller, the roller makes a revolving motion.

On the other hand, a low-pressure refrigerant gas is sucked from the suction pipe 17 and temporarily stored in a buffer section 21 formed by the cylinder 5 and the roller 11. Then, it is guided to the working chamber 16 on the suction part A side. With the revolving motion of the roller 11, the rolling contact position of the roller with respect to the inner peripheral surface of the cylinder 5 gradually moves in the circumferential direction, and the blade 15 moves in and out of the spiral groove 14. That is, the blade 15 moves in the radial direction of the roller.

The refrigerant gas guided to the working chamber 16 on the suction section A side is sequentially transferred to the working chamber 16 in the direction of the discharge section B in accordance with the revolving motion of the roller 11 from where the blade 15 is formed in a spiral shape. Is done. The pitch of the blades 15 is set so as to gradually decrease from the suction section A to the discharge section B side, and the volume of the working chamber 16 partitioned by the blades is gradually reduced, so that the refrigerant gas is sequentially transferred through the working chamber. In the working chamber closest to the discharge section B, the pressure rises to a predetermined pressure and is increased.

The high-pressure gas is discharged from the working chamber 16 of the discharge portion B and fills the first space portion 25 before the main bearing 6
Is guided to a space on the side of the electric motor unit 4 through a discharge hole 24 provided in the motor. Then, the gas is guided to a space portion on the compression mechanism portion 3 side through a gas guide hole 43 provided in a flange portion 5a of the cylinder 5, and is filled. The high-pressure gas is led to the discharge pipe 18 from where the open end of the discharge pipe 18 faces this space, and is led to the condenser therefrom.

The release groove 20 is effective in the following state. That is, under normal compression conditions, the discharge section B is formed on the left side of the drawing, and the suction section A is formed on the right side. 16 is in a high pressure state.

Accordingly, pressure is applied to the left side surface of the blade 15 in each working chamber 16, and the right side surface is pressed so as to be in close contact with the right side wall surface of the spiral groove 14. The blade 15 is similarly formed from the winding start end to the winding end end, so that the sealing of each working chamber 16 is ensured.

In an operation in which the compression ratio is low, such as at the time of start-up or low rotation, an over-compression state occurs and the pressure in the predetermined working chamber 16 exceeds the pressure on the adjacent high pressure side (discharge section B side). At this time, the blades 15 forming the predetermined working chamber 16 are pressed against the left and right adjacent working chambers 16.

That is, with reference to the predetermined working chamber 16 in the over-compressed state, the blade 15 in the right spiral groove 14 on the suction portion A side remains the spiral groove 1 as it is.
4, the blade 15 in the left spiral groove 14 on the discharge section B side is affected by overcompression, and the right side, which has been in close contact with the right side, It is separated from the wall surface and pressed so as to be in close contact with the left wall surface.

The left side wall surface of the spiral groove 14, that is, on the side of the discharge portion B, is provided with the release groove 20 as described above. The blade 15 is pressed in close contact with the release groove 20, and a gap is formed between the blade 15 and the left wall surface.

From the working chamber 16 rising to an abnormally high pressure in an overcompressed state, the wall of the spiral groove 14 on the left side and the blade 1
The high-pressure gas escapes into the spiral groove 14 through the gap with the groove 5. Then, it is further guided to the working chamber 16 on the discharge section B side through the release groove 20 provided in the spiral groove 14.

As a result, the pressure in the working chamber 16 at an abnormally high pressure immediately drops to prevent a pressure loss, and a large load is not applied to the blade 15 to maintain the compression performance and reliability. I do.

On the other hand, under the operating condition where the compression ratio is high, the width dimension X of the release groove 20 is increased as described above with reference to FIG.
The setting of the width t of the spiral groove 14 is an important condition for gas leakage countermeasures.

More specifically, as shown in FIG.
1 performs a revolving motion, and when the open end of the release groove 20 faces the position where the inner peripheral surface of the cylinder 5 and the peripheral surface of the roller 11 are in line contact, all the blades 15 are pushed into the spiral groove 14 and FIG. 3 shows a rectangular hatched seal surface shown in FIG.

At this time, gas leaks from the high pressure side H to the low pressure side L through the release groove 20. Further, the spiral groove 14
On the other hand, since the blade 15 is formed to have a clearance, the clearance on the release groove 20 side also contributes to gas leakage. However, this gas leakage factor can be suppressed and reduced to some extent by the oil seal.

More specifically, the amount of gas leakage is determined from the relationship between the clearance between the spiral groove 14 and the blade 15 and the spiral groove 14. Further, the optimum value of the clearance is determined by the width of the blade 15. Release groove 20
If the width dimension is not more than a predetermined ratio with respect to the clearance between the spiral groove 14 and the blade 15, the oil seal will not be largely broken.

FIG. 5 shows the relationship between the release groove width X and the spiral groove width t, where X is the width of the release groove 20 and t is the width of the spiral groove 14 in the state of FIG. It shows the COP ratio (%) with respect to the change in the ratio (X / t), and consequently shows the relationship between the release groove 20 and the compression performance.

The COP is called a coefficient of performance or an operation coefficient, and is a ratio between the power consumed in the refrigeration cycle (the amount of work indicated by the heat of compression) and the refrigeration capacity.
The higher the value, the higher the efficiency.

As is apparent from FIG.
It can be seen that the COP ratio drops sharply by increasing at the boundary. From this, the release (X / t) of the release groove width dimension X and the spiral groove width dimension t should be equal to or less than 0.6 (X / t ≦ 0.6). What is necessary is just to set the groove width dimension X and the spiral groove width dimension t.

FIG. 6 shows the case where the open end of the release groove 20 faces the position where the inner peripheral surface of the cylinder 5 and the peripheral surface of the roller 11 are in line contact, and the blade 15 is completely pushed into the spiral groove 14. The state is shown by a cross section of the cylinder 5 and the roller 11 in the radial direction. At this time, gas leaks from the high pressure side to the low pressure side through the release groove 20. It is described that when the width dimension of the release groove 20 is X and the diameter of the cylinder 5 is Dc, the inner circumference of the cylinder is Dc × π.

FIG. 7 shows the ratio of the width X of the release groove to the inner diameter Dc × π of the cylinder when the width of the release groove 20 is X and the inner circumference of the cylinder is Dc × π in the state of FIG. It shows the COP ratio (%) with respect to the change of (X / Dc × π), and consequently shows the relationship between the release groove 20 and the compression performance.

As can be seen from the figure, it can be seen that the X / Dc × π increases from 0.02 and the COP ratio drops sharply. From this, the ratio of the release groove width dimension X to the cylinder inner circumference Dc × π (X / Dc ×
π) is equal to or less than 0.02 (X / Dc × π ≦
0.02).

FIG. 8A shows that the open end of the release groove 20 faces the position where the inner peripheral surface of the cylinder 5 and the roller peripheral surface 11 are in line contact, and the blades 15 are all pushed into the spiral groove 14. The state at the time of putting is shown in a cross section.

At this time, the clearance is set so as to exist between the spiral groove 14 and the blade 15 as described above. Here, the sectional area of the clearance is represented by K.

On the other hand, FIG. 8B is a plan view of a part of the roller 11, and the sectional area of the semicircular release groove 20 provided in communication with the spiral groove 14 is s. At this time, as described above, gas leaks from the high pressure side to the low pressure side through the release groove 20.

FIG. 9 shows that, in the state of FIG. 8A, the sectional area of the release groove 20 is s, the sectional area of the clearance between the spiral groove 14 and the blade 15 is K, and the sectional area of the release groove s is It shows a change in the COP ratio (%) with respect to a change in the ratio (s / K) of the clearance groove area K between the spiral groove and the blade, and consequently shows the relationship between the release groove 20 and the compression performance. .

As is apparent from FIG.
It can be seen that the COP ratio drops sharply by increasing at the boundary. From this, the ratio (s / K) of the release groove cross-sectional area s to the clearance cross-sectional area K between the spiral groove and the blade is equal to or less than 2.0 (s / K).
K ≦ 2.0).

Although the above-described setting conditions are provided for the fluid compressors independent of each other, the present invention is not limited to this, and the same fluid compressor may be provided with all the setting conditions described above. It may be.

The working machines described above are all described as compressors having a helical blade type compression mechanism. However, the present invention is not limited to this, and is a pump having a helical blade type pump mechanism. It is also applicable.

[0063]

As described above, according to the present invention, under normal operating conditions, there is little performance degradation, and in an operation with a low compression ratio, abnormally high pressure is reliably released to prevent over-compression, and Gas leakage at the position where all the blades have entered the spiral groove at a high ratio can be minimized, and optimal operation is performed regardless of the compression ratio to improve compression performance and improve reliability. It has effects such as being obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a helical blade type compressor as a fluid machine, showing an embodiment of the present invention.

FIG. 2 is a perspective view of the roller of the embodiment in which a blade is wound around a spiral groove.

FIG. 3 is a view for explaining a width dimension of a release groove and a width dimension of a spiral groove in the embodiment.

FIG. 4 is a partial cross-sectional view along the axial direction of the cylinder in a state where all the blades are pushed into the spiral groove at the position of the release groove to form a seal surface in the embodiment.

FIG. 5 is a characteristic diagram of compression performance with respect to a ratio (X / t) between a release groove width dimension X and a spiral groove width dimension t in the embodiment.

FIG. 6 is a partial cross-sectional view along the radial direction of the cylinder in a state where all the blades are pushed into the helical grooves at the positions of the release grooves to form a sealing surface in the embodiment.

FIG. 7 is a characteristic diagram of compression performance with respect to a ratio (X / Dc × π) between a release groove width dimension X and a cylinder inner circumference Dc × π in the embodiment.

FIG. 8 is a cross-sectional area of a clearance between the blade and the spiral groove and a cut of the release groove in a state where all the blades are pushed into the spiral groove to form a sealing surface at the position of the release groove. The figure explaining an area.

FIG. 9 is a characteristic diagram of compression performance with respect to the ratio of the cross-sectional area s of the release groove and the cross-sectional area K between the spiral groove and the blade in the embodiment.

[Explanation of symbols]

 5: Cylinder, 11: Roller, 14: Helical groove, 16: Working chamber, 15: Blade, 3: Operating mechanism, 20: Release groove.

Claims (4)

[Claims] 1. A space between a cylinder, a roller eccentrically arranged in the cylinder, a spiral groove provided along a peripheral surface of the roller, and a cylinder which is freely fitted into and out of the spiral groove. In a fluid machine having a helical blade type operating mechanism having a helical blade partitioned and formed in a plurality of working chambers, a pressure of a predetermined working chamber is adjacent to a high pressure side wall surface of the spiral groove. When the pressure in the working chamber is exceeded, a release groove for releasing the pressure to the working chamber on the high pressure side is provided. When the width of the release groove is X and the width of the spiral groove is t, the release groove width is The ratio of the dimension X to the spiral groove width dimension t (X /
t) is equal to or less than 0.6 (X / t ≦ 0.
A fluid machine set to 6). 2. A space between a cylinder, a roller eccentrically disposed in the cylinder, a spiral groove provided along the peripheral surface of the roller, and a cylinder which is freely fitted into and out of the spiral groove. In a fluid machine having a helical blade type operating mechanism having a helical blade partitioned and formed in a plurality of working chambers, a pressure of a predetermined working chamber is adjacent to a high pressure side wall surface of the spiral groove. When the pressure in the working chamber is exceeded, a release groove for releasing this pressure to the working chamber on the high pressure side is provided. The width dimension of the release groove is X, and the inner circumference of the cylinder is Dc × π.
When the ratio (X / Dc × π) between the release groove width dimension X and the cylinder inner circumference Dc × π is equal to or less than 0.02 (X / Dc × π ≦ 0.02), A fluid machine characterized by setting. 3. A cylinder, a roller eccentrically arranged in the cylinder, a spiral groove provided along a peripheral surface of the roller, and a space between the cylinder and the cylinder which is freely fitted into and out of the spiral groove. In a fluid machine having a helical blade type operating mechanism having a helical blade partitioned and formed in a plurality of working chambers, a pressure of a predetermined working chamber is adjacent to a high pressure side wall surface of the spiral groove. When the pressure in the working chamber is exceeded, a release groove for releasing this pressure to the working chamber on the high pressure side is provided, the sectional area of the release groove is s, and the clearance sectional area between the spiral groove and the blade is K. The ratio (s / K) of the release groove cross-sectional area s to the clearance cross-sectional area K between the spiral groove and the blade was set to be equal to or less than 2.0 (s / K ≦ 2.0). Fluid machine characterized by that . 4. A space between a cylinder, a roller eccentrically disposed in the cylinder, a spiral groove provided along a peripheral surface of the roller, and a cylinder which is fitted into and out of the spiral groove so as to freely come and go. In a fluid machine having a helical blade type operating mechanism having a helical blade partitioned and formed in a plurality of working chambers, a pressure of a predetermined working chamber is adjacent to a high pressure side wall surface of the spiral groove. When the pressure in the working chamber is exceeded, a release groove for releasing the pressure to the working chamber on the high pressure side is provided. When the width of the release groove is X and the width of the spiral groove is t, the release groove width is The ratio (X / t) of the dimension X to the spiral groove width dimension t is equal to or less than 0.6 (X / t).
≦ 0.6) and the ratio of the release groove width dimension X to the cylinder inner circumference Dc × π (X / Dc ×
π) is equal to or less than 0.02 (X / Dc × π
≦ 0.02), when the sectional area of the release groove is s and the clearance sectional area between the spiral groove and the blade is K, the clearance area between the release groove s and the clearance between the spiral groove and the blade is broken. The ratio (s / K) to the area K is equal to or less than 2.0 (s / K).
K ≦ 2.0).