JPH0882295A - Helical blade type compressor - Google Patents

Abstract

PURPOSE: To improve the compression efficiency of a compressor by decreasing stress concentration applied to a helical blade. CONSTITUTION: A helical groove 17 provided with a pair of spiral groove walls 17a, 17b is formed at the outer periphery 16a of a roller piston 16. In the helical groove 17, a helical blade 18 made of elastic material is formed so as to advance and retreat. A curved surface is formed at the edge part 26 of a low pressure side groove wall 17a. The curved surface is brought into contact with the low pressure side groove wall 17a and the outer periphery 16a of the roller piston 16 in a cross section orthogonal to the helical groove 17, and its radius of curvature is 0.1mm-0.7mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helical blade type compressor incorporated in an air conditioner or a refrigeration cycle, and more particularly to a helical blade type compressor capable of extending compression efficiency and life.

[0002]

2. Description of the Related Art A conventional helical blade compressor will be briefly described with reference to FIGS. As shown in FIG. 15, the compressor has a compressor section 10 and an electric motor section 11, which are concentrically housed in a hermetically sealed casing 12.

Next, the structure and principle of the compressor section 10 will be briefly described. Inside the hollow cylindrical cylinder 15, a roller piston 16 is provided rotatably around a parallel axis eccentric from the central axis O of the cylinder 15. Helical grooves 17 are provided on the outer peripheral surface of the roller piston 16 in a spiral shape with unequal intervals in the axial direction, that is, the pitch gradually changes from one end to the other end. Further, a helical blade 18 is attached to the helical groove 17 of the eccentric roller piston 16.

The helical blade 18 has a rectangular cross section and a spiral shape substantially along the helical groove 17 of the roller piston 16, and slides in and out of the helical groove 17. The outer surface of the helical blade 18 is in sliding contact with the inner peripheral surface of the cylinder 15.

A plurality of compression chambers 25a, 25b, 25c are formed by the inner peripheral surface of the cylinder 15, the outer peripheral surface of the roller piston 16 and the helical blade 18. That is, by partitioning the space between the inner circumference of the cylinder 15 and the outer circumferential surface of the eccentric roller piston 16 by the helical blade 18 which is spiral and whose pitch decreases from one end side to the other end side, Multi-stage compression chambers 25a, 25b, 25c each having a substantially crescent-shaped cross section are formed.

In the reciprocating type compressor which has been conventionally used for air conditioning, a sealing property around the compression chamber is required. Therefore, the edge chamfering of the sliding component is about 0.1 mm. Or, it is buffed.

In the conventional helical blade type compressor, the edge is machined in accordance with the preceding example. The cross section of the helical blade 18 perpendicular to the spiral direction has a substantially rectangular shape. FIG. 14 shows an enlarged view of the helical blade. Of these, FIG. 14A is a cross-sectional view as seen from a direction perpendicular to the spiral direction of the helical blade 18, and the arrow in the drawing represents the pressure. In FIG. 14A, the high pressure gas acts on the left side surface of the helical blade 18 and the helical groove 17, and the low pressure gas acts on the right side surface of the helical blade 18. Further, FIG. 14 (b),
14 (c) and 14 (d) are enlarged views of the portion A in FIG. 14 (a) near the edge of the helical groove 17. Thread chamfering (b), R chamfering (c) and buffing (d) are performed on the edge portion of the helical groove 17, and the corners are thus cut off.

[0008]

However, the conventional helical blade compressor has the following disadvantages. That is, as shown in FIG. 14A, in most cases, during compression operation, the helical blade 18 is pushed toward the low pressure chamber side (right side in FIG. 14A) by the pressure difference between the compression chambers, and the helical groove 17 is pressed. It contacts one of the walls and slides. Further, since the high pressure gas also flows into the helical groove 17, the helical blade 18 also contacts the inner peripheral wall of the cylinder 15 and slides. During operation, the helical blade 18 has a helical groove 1
Although it repeatedly goes in and out in 7, the stress concentration occurs in the helical blade 18 near the contact with the piston edge corner due to the pressure difference acting on the helical blade 18.

Up to now, the edge portion of the helical groove 17 of the roller piston 16 has been chamfered with a thread chamfer of about 0.1 mm, as in the case of a reciprocating type compressor (see FIG. 14).
(B)), R chamfering (Fig. 14 (b)) and buffing (Fig. 14 (c)). When the operation is performed in these states, in the vicinity of the edge portion of the helical groove 17 of the helical blade 18 which is in contact with the edge portions of FIGS. 14 (b), (c),
Stress concentration occurs as shown in (d). In particular, when the helical blade 18 is in a positional relationship such that it is most protruded from the inside of the helical groove 17, the stress value of the helical blade 18 in contact with the edge portion of the helical groove 17 becomes high.
Therefore, the helical blade 18 may be deformed / abnormally worn, and if the operation is continued in this state, the performance is degraded and the rotation is locked.

Further, as shown in FIG. 14C, it is obvious that stress concentration can be reduced by increasing the radius R of the helical groove 17 of the roller piston 16. But in this case,
As shown in FIG. 16, if the R of the edge portion is large, the portion 19 surrounded by this R, the cylinder 15 and the helical blade 18 will not be compressed between the compression chambers when the helical blade 18 is completely inserted in the helical groove 17. Will result in a large gap. Therefore, if the radius R of the edge portion is increased too much, the sealing performance is deteriorated and the amount of leakage of the compressed refrigerant between the compression chambers is increased, resulting in a decrease in efficiency and capacity.

The present invention has been made in consideration of the above points, and satisfies the sealing function required by the helical blade of the compressor portion, and high stress concentration at the edge portion of the helical groove received by the helical blade. It is an object of the present invention to provide a helical blade type compressor capable of reducing the above-mentioned problem and extending the life of the compressor itself.

[0012]

According to the first aspect of the present invention,
A hollow cylindrical cylinder, a roller piston that is provided inside the cylinder and that rotates around a rotation axis that is eccentric from the center axis of the cylinder, and a pair of groove walls that are provided spirally along the axial direction on the outer peripheral surface of the roller piston. And a helical blade made of an elastic material provided in the helical groove so as to be able to move forward and backward, the edge portion of the low-pressure side groove wall of the pair of groove walls of the helical groove, and a cross section orthogonal to the helical groove. In the helical blade type compressor, an edge curved surface having a curvature radius of 0.1 mm to 0.7 mm in contact with the low pressure side groove wall and the roller piston outer peripheral surface is formed.

According to a second aspect of the present invention, a hollow cylindrical cylinder, and a roller piston that is provided inside the cylinder and that rotates about a rotation axis that is eccentric from the center axis of the cylinder,
A helical groove provided on the outer circumferential surface of the roller piston along the axial direction and having a pair of groove walls, and a helical blade made of an elastic material that is provided in the helical groove so as to move forward and backward, and the helical groove In the edge portion of the low pressure side groove wall of the pair of groove walls, an edge curved surface is formed which is in contact with the low pressure side groove wall in a cross section orthogonal to the helical groove and a radially outer surface parallel to the roller piston outer peripheral surface. This is a helical blade compressor.

According to a fourth aspect of the present invention, a hollow cylindrical cylinder, and a roller piston that is provided inside the cylinder and that rotates about a rotation axis that is eccentric from the center axis of the cylinder,
A helical groove provided on the outer circumferential surface of the roller piston along the axial direction and having a pair of groove walls, and a helical blade made of an elastic material that is provided in the helical groove so as to move forward and backward, and the helical groove The low-pressure side groove wall of the pair of groove walls is a helical blade compressor characterized in that the low-pressure side groove wall inclines toward the low-pressure side radially outward in a cross section orthogonal to the helical groove.

According to a fifth aspect of the present invention, a hollow cylindrical cylinder, and a roller piston that is provided inside the cylinder and that rotates about a rotation axis that is eccentric from the center axis of the cylinder,
A helical groove provided on the outer circumferential surface of the roller piston along the axial direction and having a pair of groove walls, and a helical blade made of an elastic material that is provided in the helical groove so as to advance and retract, and the helical blade The low-pressure side surface is a helical blade compressor characterized in that, in a cross section orthogonal to the helical groove, the surface is inclined outward in the radial direction toward the high-pressure side.

According to a sixth aspect of the present invention, a hollow cylindrical cylinder, and a roller piston that is provided inside the cylinder and that rotates around a rotation axis that is eccentric from the center axis of the cylinder,
The helical groove is provided on the outer peripheral surface of the roller piston in a spiral shape along the axial direction and has a pair of groove walls, and a helical blade made of an elastic material and movable in and out of the helical groove. The edge portion of the groove wall of the groove type with respect to the low-pressure side is formed by a part of a curve drawn by an arbitrary function such that the result of the second differentiation is continuous in the cross section orthogonal to the helical groove. It is a formula compressor.

[0017]

According to the first aspect of the present invention, since the edge curved surface having a radius of 0.1 mm to 0.7 mm which is in contact with the low pressure side groove wall and the roller piston outer peripheral surface is formed at the edge portion of the low pressure side groove wall. It is possible to reduce the clearance at the edge portion and reduce the stress concentration applied to the helical blade.

According to the second aspect of the invention, the center of the edge curved surface formed at the edge portion of the low-pressure side groove wall is shifted outward in the radial direction, so that the size of the edge curved surface can be increased without increasing the clearance at the edge portion. Can be increased.

According to the invention described in claim 4, the low pressure side groove wall of the helical groove is inclined outward in the radial direction toward the low pressure side, so that the helical blade can be formed without increasing the clearance at the edge portion of the low pressure side groove wall. It is possible to reduce the stress concentration applied to.

According to the invention described in claim 5, since the surface of the helical blade on the low pressure side is inclined radially outward toward the high pressure side, the helical blade can be formed without increasing the clearance at the edge portion of the low pressure side groove wall. The stress concentration applied to the blade can be reduced.

According to the sixth aspect of the present invention, since the edge portion of the low-pressure side groove wall is formed from a part of a curve drawn by an arbitrary function such that the result of the second-order differentiation is continuous, the low-pressure side groove wall is formed. It is possible to reduce the stress concentration applied to the helical blade without increasing the clearance at the edge portion.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment An embodiment of the present invention will be described below with reference to the drawings. 1, 2 and 9 are views showing a first embodiment of a helical blade type compressor according to the present invention.

As shown in FIG. 1, the helical blade compressor has a hollow cylindrical cylinder 15 and a roller piston 16 which is provided inside the cylinder 15 and rotates around a rotation axis eccentric from the center axis of the cylinder. A compressor unit 10 is provided. A helical groove 17 is provided on the outer peripheral surface of the roller piston 16 in a spiral shape along the axial direction. The helical groove 17 includes a pair of groove walls 17a,
The groove wall 17a is a low-pressure side groove wall, and the groove wall 17b is a high-pressure side groove wall.

Further, in the helical groove 17, a helical blade 18 made of a material (elastic material) having elasticity as compared with metal such as a polymer material is provided so as to be able to move back and forth. The outer peripheral surface of the helical blade 18 is in sliding contact with the inner peripheral surface of the cylinder 15, and the inner peripheral surface of the cylinder 15, the outer peripheral surface of the roller piston 16, and the helical blade 18 form a plurality of multi-stage compression chambers 25a, 25b, 25c. ing. The compression chambers 25a, 25b, 25c are
The pressure gradually increases from a toward the compression chamber 25c.

Further, as shown in FIGS. 1 and 2, a curved surface shape (hereinafter referred to as R) having an R-shaped curvature is formed on the edge portion 26 of the low pressure side groove wall 17a of the helical groove 17. As shown in FIG. 2, this R is in contact with the low pressure side groove wall 17a and the outer peripheral surface 16a of the roller piston 16 in a cross section orthogonal to the helical groove 17, and the radius of this R is 0.1 mm to 0.7 mm. Has become.

Next, referring to FIG. 9, the groove wall 1 of the helical groove 17 is shown.
The relationship between the radius of R and the coefficient of performance of the compressor when the R formed on the edge portion 26 of 7a contacts the groove wall 17a and the outer peripheral surface 16a of the roller piston 16 will be described. If the helical blade 18 is made of a metal-based material, if the radius of the R of the edge portion 26 is 0.1 mm or more, the leakage of the refrigerant is large, the efficiency is deteriorated, and the helical blade 18 does not function as a compressor.

However, since the helical blade 18 is made of an elastic material which is relatively soft as compared with a metal such as a polymer material, the R of the edge portion 26 of the helical groove 17 is rounded.
Even if the radius is 0.1 mm or more, the helical blade 18 is properly deformed in the helical groove 17 into the shape of the helical groove 17, and the helical blade 18 becomes uniform to some extent. Therefore, the sealing performance of the helical blade 18 is maintained, and the coefficient of performance does not drop. Therefore, it is possible to make the size of the clearance larger than that of the conventional reciprocating type compressor.

Naturally, since the stress concentration is reduced by increasing the radius R of the edge portion 26, the helical blade 1
8 can improve reliability. However, there are limits to that. As shown in FIG. 9, the helical groove 17
When R that is in contact with the groove wall 17a and the outer peripheral surface of the roller piston 16 is formed in the edge portion 26, the limit value of the magnitude of R at which the coefficient of performance drops is a radius of R = 0.3 mm, 60 Hz at 30 Hz operation. In operation, the radius of R is 0.7 mm. Here, it is preferable that a high coefficient of performance is realized at a high rotation speed of 60 Hz or higher where a high refrigeration efficiency is obtained in a general operating condition. In this case, the upper limit of the radius of R formed on the edge portion 26 of the helical groove 17 is 0.7 mm.

Further, FIG. 10 shows the relationship between the radius of R of the edge portion 26 calculated by the inventor and the maximum stress value generated in the helical blade 18, showing that the differential pressure acting on the helical blade 18 is 5 kgf / cm ² and 10 kgf / The case of cm ² is shown. If the radius of R of the edge portion 26 is small,
The maximum stress value generated in the helical blade 18 becomes large. When the pressure difference is 5 kgf / cm ² , the edge part 2
If the radius of R of 6 becomes smaller than 0.1 mm, the pressure resistance limit value of the polymer material of the helical blade 18 will be exceeded, and wear will occur over a short operating time. During steady operation,
If the differential pressure acting on the helical blade 18 is small,
It is about kgf / cm ² , and the lower limit of the radius of R of the edge portion 26 is 0.1 mm.

In this embodiment, the radius of R is 0.7 mm.
Since it is below, high sealability can be maintained, and since the radius of R is 0.1 mm or more, it can be used with a stress within the pressure resistance limit value of the polymer material. Therefore, it is possible to satisfy the sealing function required by the helical blade 18, reduce high stress concentration near the edge portion 26 of the helical groove 17 which the helical blade 18 receives, and achieve the required life of the compressor itself.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. 3 and 11. In FIG. 3, the same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 3 is a view of the helical blade 18 seen from a cross section in a direction orthogonal to the helical groove 17, and the helical blade 18 near the edge portion 26 of the helical groove 17 is shown.
FIG. As described in the first embodiment, if the radius of R of the edge portion 26 of the helical groove 17 is increased, the high stress concentration near the edge portion 26 received by the helical blade 18 can be reduced. Therefore, the radius of R of the edge portion 26, which is the upper limit value in the first embodiment, is 0.7.
If it can be made larger than mm, the reliability of the helical blade 18 can be improved and the life of the compressor can be further extended. However, the radius of R is 0.7 with the shape of the edge portion 26 as in the first embodiment.
If the value is further increased from mm, as shown in FIG. 9, the sealing property is deteriorated and the coefficient of performance is lowered.

Therefore, in this embodiment, the edge portion 2
2 so that the R of 6 contacts the groove wall 17a of the helical groove 17 and the radially outer surface 27 parallel to the outer peripheral surface 16a of the roller piston 16 as compared with the case shown in FIG. They are staggering. Edge part like this
With the shape, the R of the edge portion 26 can be increased without increasing the clearance of the edge portion 26.

Therefore, the helical blade 18 can satisfy the required sealing function, and high stress concentration near the edge portion 26 received by the helical blade 18 can be reduced, so that the required life of the compressor itself can be achieved.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIG.

FIG. 11 shows the relationship between the radius of R of the edge portion 26 and the coefficient of performance of the compressor when the R shape of the edge portion 26 is in contact with the groove wall 17a of the helical groove 17 and is in contact with the surface 27. Has been done. In the first embodiment, the upper limit value of the radius of R required to maintain the high coefficient of performance of the compressor was 0.7 mm, but as shown in FIG. 11, the center of R is the outer peripheral surface of the roller piston 16. The radius of R can be increased up to 20 mm by displacing it radially outward from the contact with 16a. In addition, if R is made larger than this, due to the pressure acting on the helical blade 18,
Since the helical blade 18 elastically deforms and the tip of the edge portion 26 comes into contact with the blade 18, the helical blade 18 may come into contact with the tip of the R and abnormal wear may occur. Therefore, the upper limit of R is preferably 20 mm. It is obvious that if the radius R of the edge portion 26 can be made as large as possible, the high stress concentration near the edge portion 26 that the helical blade 18 receives can be further reduced.

Accordingly, the helical blade 18 can satisfy the required sealing function, and high stress concentration near the edge portion 26 received by the helical blade 18 can be reduced, so that the reliability of the helical blade 18 can be improved and the requirement of the compressor itself can be obtained. A lifetime can be achieved.

Fourth Embodiment Next, a fourth embodiment of the present invention will be described with reference to FIGS. 4 and 12. In FIG. 4, the same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 4A is a view of the helical blade 18 as seen from a cross section in a direction orthogonal to the helical groove 17, and FIGS. 4B and 4C are the helical blade 18 and the helical groove 1.
7 is an enlarged view of an A portion of FIG. 4A of the edge portion 26 of FIG.

Of the two groove walls 17a and 17b, when viewed in a cross section orthogonal to the helical groove 17, the low-pressure side groove wall 17
a is the low-pressure compression chamber side (the right side in FIG. 4) radially outward.
Leaning toward. In this case, the relationship between the inclination and the maximum stress value generated near the edge portion 26 received by the helical blade 18 is as shown in FIG.

As shown in FIG. 12, it can be seen that the maximum stress value is reduced by inclining the low pressure side groove wall 17a of the helical groove 17 outward in the radial direction toward the low pressure compression chamber side. Further, even if the low-pressure side groove wall 17a is inclined, the helical blade 18 is an elastic body such as a polymer material, and therefore, when it enters the helical groove 17 due to the load applied during operation, the helical blade 18 has a groove shape to some extent. Deforms together.
Therefore, the clearance between the compression chambers 25a to 25c does not become large, and the sealing performance does not deteriorate. Therefore, it is possible to satisfy the sealing function required by the helical blade 18, reduce high stress concentration near the edge portion 26 received by the helical blade 18, and achieve the required life of the compressor itself.

Fifth Embodiment Next, a fifth embodiment of the present invention will be described with reference to FIGS. In FIG. 5, the same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 5A is a view of the helical blade 18 seen from a cross section in a direction orthogonal to the helical groove 17, and FIGS. 5B and 5C are the helical blade 18 and the helical groove 1.
7 is an enlarged view of a portion A of FIG. 5A of the edge portion 26 of FIG.

When viewed in a cross section orthogonal to the helical groove 17, the surface 18a of the helical blade 18 on the low pressure side that slides on the groove wall 17a on the low pressure side is radially outwardly directed toward the high pressure compression chamber (see FIG. 5). Leaning to the left). In this case, the relationship between the inclination and the maximum stress value generated in the vicinity of the edge portion 26 received by the helical blade 18 is as shown in FIG.
It can be seen that the maximum stress value of the helical blade 18 is small because the low-pressure side surface 18a that slides on the low-pressure side groove wall 17a is inclined radially outward toward the high-pressure compression chamber side. Further, even if the surface 18a of the helical blade 18 is inclined, since the helical blade 18 is an elastic body such as a polymer material, when the helical blade 18 enters into the helical groove 17 due to a load applied during operation, the helical blade 18 will have a groove to some extent. Transforms into the shape of. Therefore, the clearance between the compression chambers 25a to 25c does not become large, and the sealing performance does not deteriorate. Therefore, the helical blade 18 satisfies the required sealing function, and at the same time, the helical blade 18
It is possible to reduce high stress concentration in the vicinity of the edge portion 26 received by the compressor and to achieve the required life of the compressor itself.

Sixth Embodiment Next, a sixth embodiment of the present invention will be described with reference to FIG. In FIG. 6, the same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 6 is a view of the helical blade 18 seen from a vertical cross section in a direction orthogonal to the helical groove 17, and shows the helical blade 18 and the edge portion 26 of the helical groove 17.
FIG. When viewed in a cross section orthogonal to the helical groove 17, of the two groove walls 17a and 17b of the helical groove 17, at least the edge portion 26 of the low-pressure side groove wall 17a is
When the rotation axis of the roller piston 16 is the x axis and the axis orthogonal to this x axis is the y axis, the relational expression of x, y y = f
In (x), the result of second-order differentiation of y with respect to x is drawn by an exponential function, a trigonometric function, an inverse trigonometric function, a hyperbolic function, an inverse hyperbolic function, or the like having a continuous distribution.

According to this embodiment, the helical blade 18
Can satisfy the required sealing function, reduce high stress concentration near the edge portion 26 received by the helical blade 18, and achieve the required life of the compressor itself.

In addition to the first to sixth embodiments, as shown in FIGS. 7 (a) and 7 (b), the helical blade 18
The cross section orthogonal to the helical groove may be inclined. That is, the both side surfaces 18a and 18b of the helical blade 18 are not limited to straight lines but may be curved lines. Further, the two side surfaces 18a and 18b may both be inclined or may have a trapezoidal shape.

Further, as shown in FIG. 8, the helical groove 1
In addition to providing R or forming a curved surface on the edge portion 26 of the low pressure side groove wall 17a of FIG. 7, R may be provided or forming a curved surface on the edge portion 27 of the high pressure side groove wall 17b.

The above-mentioned embodiments can be used individually, but can also be used in combination. For example, FIG. 4C shows a combination of the fourth and sixth embodiments, and FIG. 5B shows a combination of the second and fifth embodiments. By using the embodiments in combination as described above, it is possible to expect a further effect.

[0051]

As described above, according to the present invention,
It is possible to reduce the stress concentration applied to the helical blade without increasing the clearance at the edge portion of the low pressure side groove wall of the helical groove. Therefore, the life of the compressor can be extended and the compression efficiency of the compressor can be improved.

[Brief description of drawings]

FIG. 1 is an overall sectional view showing a first embodiment of a helical blade type compressor according to the present invention.

FIG. 2 is an enlarged view of an edge portion of a low pressure side groove wall.

FIG. 3 is an enlarged view of an edge portion of a low pressure side groove wall of a helical groove showing a second embodiment of the present invention.

FIG. 4 is an enlarged view of an edge portion of a low pressure side groove wall of a helical groove showing a third embodiment of the present invention.

FIG. 5 is an enlarged view of an edge portion of a low pressure side groove wall of a helical groove showing a fourth embodiment of the present invention.

FIG. 6 is an enlarged view of an edge portion of a low-pressure side groove wall of a helical groove showing a fifth embodiment of the present invention.

FIG. 7 is a view showing a side surface shape of a helical blade showing a modified example of the invention.

FIG. 8 is a view showing a groove wall of a helical groove showing a modified example of the invention.

FIG. 9 is a diagram showing the relationship between the radius of R and the coefficient of performance in the first embodiment of the present invention.

FIG. 10 is a diagram showing the relationship between the radius of R and the maximum stress value in the first embodiment of the present invention.

FIG. 11 shows R in the second and third embodiments of the present invention.
The figure which shows the relationship between the radius and the coefficient of performance.

FIG. 12 is a diagram showing the relationship between the inclination angle of the low-pressure side groove wall and the maximum stress value in the fourth example of the present invention.

FIG. 13 is a diagram showing the relationship between the inclination angle of the surface on the low pressure side of the helical blade and the maximum stress value in the fifth embodiment of the present invention.

FIG. 14 is a view showing an edge portion of a low pressure side groove wall of a helical groove of a conventional helical blade compressor.

FIG. 15 is an overall sectional view of a conventional helical blade compressor.

FIG. 16 is a diagram showing a clearance of an edge portion of a conventional helical blade compressor.

[Explanation of symbols]

 15 Cylinder 16 Roller piston 17 Helical groove 17a Low pressure side groove wall 17b High pressure side groove wall 18 Helical blade 18a Low pressure side surface 18b High pressure side surface 25a, 25b, 25c Compression chamber 26 Edge part

Claims (6)

[Claims] 1. A hollow cylindrical cylinder, a roller piston that is provided inside the cylinder and that rotates around a rotation axis that is eccentric from the center axis of the cylinder, and that is provided spirally on the outer circumferential surface of the roller piston along the axial direction. A helical groove having a pair of groove walls together with a helical blade made of an elastic material that is provided in the helical groove so as to advance and retreat, and the helical groove is provided at the edge portion of the low-pressure side groove wall of the pair of groove walls of the helical groove. In a cross section orthogonal to the groove, a radius of curvature of 0.1 mm which is in contact with the groove wall on the low pressure side and the outer peripheral surface of the roller piston
A helical blade type compressor characterized by forming an edge curved surface having a curvature of 0.7 mm. 2. A hollow cylindrical cylinder, a roller piston that is provided inside the cylinder and that rotates around a rotation axis that is eccentric from the center axis of the cylinder, and that is provided spirally on the outer peripheral surface of the roller piston along the axial direction. A helical groove having a pair of groove walls together with a helical blade made of an elastic material that is provided in the helical groove so as to advance and retreat, and the helical groove is provided at the edge portion of the low-pressure side groove wall of the pair of groove walls of the helical groove. A helical blade type compressor characterized in that an edge curved surface is formed in contact with a low-pressure side groove wall and a radially outward surface parallel to the roller piston outer peripheral surface in a cross section orthogonal to the groove. 3. The helical blade compressor according to claim 2, wherein the radius of curvature of the edge curved surface formed on the edge portion of the low pressure side groove wall is 0.1 mm to 20 mm. 4. A hollow cylindrical cylinder, a roller piston that is provided inside the cylinder and that rotates around a rotation axis that is eccentric from the center axis of the cylinder, and that is provided spirally on the outer peripheral surface of the roller piston along the axial direction. And a helical groove having a pair of groove walls, and a helical blade made of an elastic material that is provided in the helical groove so as to move forward and backward, and the low-pressure side groove wall of the pair of groove walls of the helical groove is orthogonal to the helical groove. The helical blade type compressor is characterized in that it inclines toward the low pressure side radially outward in the cross section. 5. A hollow cylindrical cylinder, a roller piston which is provided inside the cylinder and rotates around a rotation axis which is eccentric from the center axis of the cylinder, and which is provided spirally on the outer peripheral surface of the roller piston along the axial direction. A helical groove having a pair of groove walls together, and a helical blade made of an elastic material that is provided in the helical groove so as to be able to advance and retreat, and the surface on the low pressure side of the helical blade has a radius in a cross section orthogonal to the helical groove. A helical blade type compressor characterized in that it inclines toward the high pressure side in the outward direction. 6. A hollow cylindrical cylinder, a roller piston that is provided inside the cylinder and that rotates around a rotation axis that is eccentric from the center axis of the cylinder, and that is provided spirally on the outer peripheral surface of the roller piston along the axial direction. A helical groove having a pair of groove walls together, and a helical blade made of an elastic material that is provided in the helical groove so as to be able to move forward and backward, and the edge portion of the pair of groove type low pressure side groove walls of the helical groove is a helical groove. A helical blade type compressor characterized in that it is formed from a part of a curve drawn by an arbitrary function such that the results of second-order differentiation are continuous in a cross section orthogonal to the groove.