JP2758182B2 - Fluid compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a fluid compressor for compressing refrigerant gas of a refrigeration cycle, for example.

(Related Art) As a fluid compressor generally used for compressing a refrigerant of a refrigeration cycle, a reciprocating compressor and a rotary compressor are known. However, such a fluid compressor has a drawback that its structure is complicated and the number of parts is large.

In order to solve such a problem, Japanese Patent Application No.
No. 92 (not disclosed) and other compressors are under development. This compressor is configured as shown in FIGS. 5 and 6, for example. The compressor 1 has an outer wall formed by a closed container 2, and a cylinder 3 is provided at a substantially central portion of the closed container 2. The cylinder 3 is formed in a circular tubular shape, and a rotor 4 is externally fitted to an outer wall substantially at the center between the ends. A stator 5 is provided at a position corresponding to the outer peripheral surface of the rotor 4 with a small gap. The stator 5 is positioned concentrically outside the rotor 4, and the outer peripheral surface is fitted and fixed to the inner peripheral surface of the closed casing 2.

In this way, the cylinder 3 driven to rotate by the motors 4 and 5 has first and second bearing portions 6 and 7 at both ends.
The first bearing 6 has a suction port 8 formed on one side thereof, and the inside of the cylinder 3 and a suction pipe 9 connected from the outside of the closed casing 2 are communicated with each other. .

Further, the other second bearing portion 7 is formed with a discharge port 10 for communicating the inside of the cylinder 3 and the inside of the sealed container 2.

In such a cylinder 3 is provided a rotor piston 11 having a parallel axis that is decentered by a predetermined dimension d with respect to the center of rotation of the cylinder 3. At both ends of the rotor piston 11, support shafts 12, 13 rotatably supported by the first and second bearings 6, 7 are provided.
The rotor piston 11 is supported at a position where a part of the peripheral surface is in contact with the inner peripheral surface of the cylinder 3. Further, a helical blade groove 14 is formed on the peripheral surface of the rotor piston 11, and the blade groove 14 has a gradual pitch from the suction port 8 side toward the discharge port 10 side as shown in FIG. Are formed in a spiral shape, and the cross-sectional shape is formed in a concave shape.

A blade 15 formed in a spiral shape with elasticity is inserted into the blade groove 14. This blade 15 is formed with a rectangular cross section corresponding to the blade groove 14,
The inner peripheral edge is always located in the blade groove 14 of the rotor piston 11, and the outer peripheral edge is always in contact with the inner peripheral surface of the cylinder 3.

A projection 3a is formed on the inner peripheral surface of the cylinder 3 so as to protrude inward. The rotor piston 11 corresponding to the projection 3a is provided with an engagement hole for engaging the projection 3a. ing. By rotating the cylinder 3, the rotor piston 11 is also rotated.

Further, the second bearing portion 7 is formed with a conduit 16 for communicating the end of the support shaft portion 13 and the lower portion inside the closed casing 2, and the lubricating oil 17 contained in the lower portion is used as a sliding portion. To be supplied.

In the compressor 1 configured as described above, the motors 4 and 5 are driven to rotate the cylinder 3, and the rotation of the cylinder 3 causes the rotor piston 11 to rotate at the same speed. At this time, since the center of rotation of the cylinder 3 and the rotor piston 11 is displaced, the blade 15 protrudes from a portion where the gap is opened, and a plurality of operation chambers are formed.
The volumes of these operation chambers change according to the helical pitch of the blades 15, and the volumes decrease from the suction port 8 side to the protrusion port 10 side. When the rotor piston 11 rotates, the volume of the compressed gas (refrigerant gas) sucked from the suction port 8 is reduced steplessly while the operation chamber partitioned by the helical blade 15 moves in the axial direction. ,
It is designed to be sent to the discharge port 10 side.

The compressed refrigerant gas is released into the closed container 2 and is further discharged from a discharge pipe 18 provided in a wall of the closed container 2 in a penetrating state.

Such a compressor 1 has the advantage that the structure is simpler than that of a conventional compressor and the number of parts can be reduced.

However, since the helical blade 15 is formed of an elastic body, there is a problem that gas leak easily occurs particularly with the inner peripheral surface of the cylinder 3.

(Problems to be Solved by the Invention) Recently developed compressors require the helical blade to be made of an elastic body, and in particular, those in which gas leaks easily occur between the helical blade and the inner peripheral surface of the cylinder. Met.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to provide a fluid compressor that can reliably contact a helical blade against an inner peripheral surface of a cylinder and reduce the occurrence of gas leaks.

[Configuration of the invention]

(Means for Solving the Problems) In order to satisfy the above object, a fluid compressor according to the present invention includes, as claim 1, a cylinder formed of a hollow cylinder, a cylindrical piston eccentrically arranged in the cylinder, A spiral groove formed on the peripheral surface of the piston so that the pitch decreases from the suction side to the discharge side; And a small pitch groove portion of one turn or less is formed at an end of the blade groove on the suction side.

As a second aspect, a cylinder composed of a hollow cylinder, a cylindrical piston eccentrically arranged in the cylinder,
A spiral groove formed on the peripheral surface of the piston so as to decrease the pitch from the suction side to the discharge side, and a plurality of operation chambers fitted between the piston and the cylinder so as to protrude and retract into the groove. And the blade has a height h in the protruding and retracting direction and a width t.
It is characterized by being formed in a larger rectangular shape.

(Operation) (1) By forming a small pitch groove of one turn or less at the suction-side end of the blade groove formed on the outer peripheral surface of the cylinder, the suction-side end of the blade with a large pitch is adjusted to the cylinder. The blade can be strongly pressed against the inner wall, and the adhesion of the blade to the inner wall of the cylinder can be enhanced.

(2) The rigidity of the blade located between adjacent working chambers having a pressure difference is increased by making the dimension h of the cross-sectional shape of the blade in the protruding and retracting direction larger than the width dimension t, so that the blade with respect to the cylinder The contact state can be maintained.

(Embodiment) A first embodiment of the present invention will be described with reference to FIGS. Since the basic structure of one embodiment of the present invention is the same as the conventional structure, only the improvements will be shown and described.

The cylinder 3 shown in the figure is provided so as to be rotationally driven via a motor structure in a closed container as described in the conventional structure. The cylinder 3 is formed of a hollow cylindrical body, and the center of the cylinder 3 and the center of rotation coincide with each other.

One end of the cylinder 3 is provided with a refrigerant gas inlet, and the other end is formed with a discharge port.

A rotor piston 20 parallel to the center of rotation is provided inside the cylinder 3. The center of rotation of the rotor piston 20 is supported at a distance d from the center of rotation of the cylinder 3.
Are abutted on the inner peripheral surface of the cylinder 3. The rotor piston 20 is driven to rotate in the same direction at the same angular velocity as the cylinder 3 rotates.

Further, a helical blade groove 21 is formed on the peripheral surface of the rotor piston 20. The pitch of the helical shape of the blade groove 21 from the position indicated by A to the position indicated by Z is the same as the discharge side I. Is formed so that the pitch increases from the inlet side to the suction side II. And the blade groove 21
A small pitch groove portion 22 is further formed at the end Z on the suction side. The small pitch grooves 22 are formed smaller than the pitch of the grooves on the suction side. Here, the rotor piston is brought close to the Z position where the small pitch groove portion 22 starts.
A suction groove 22a is formed in the axial direction of 20. This suction groove 2
2a is provided to limit the excluded volume indicated by the hatched portion V. By providing the suction groove 22a, the resistance to the suction of the refrigerant gas is reduced. A spirally formed blade 23 is fitted in the blade groove 21 including the small pitch groove portion 22.

This state is shown in FIG. Blade 23 as shown
Is in the state shown in FIG. 3 in the related art, and the force of pressing the blade 23a located at the suction side end II against the inner wall surface of the cylinder 3 is caused by the blade 23b located diagonally opposite to the blade 23a. I do. Here, the blades 23a and 23b each indicate a part of the same blade 23. That is, by the input of the arrow B, the force of the arrow A acts,
The closed state between the cylinder 3 and the blade 23 is maintained.

In contrast, the present invention has two portions for pressing the blade 23a. A blade 23b and a blade 23c located in the small pitch groove 22. Two portions of these blades 23 come into contact with the cylinder 3 and are pressed in the directions of arrows E and F. As a result, the blade 23a is pressed in the direction of arrow G. That is, since the blade 23c is located at a position close to the blade 23a, the force for pressing the blade 23a against the cylinder 3 can be increased, and the occurrence of gas leak between the blade 23 and the inner peripheral surface of the cylinder 3 can be prevented.

Hereinafter, a second embodiment of the present invention will be described with reference to FIG. 4. However, since the basic structure of the fluid compressor to be implemented is the same as that shown in the conventional example, only the differences in the structure will be described. It is illustrated and described. The blade 23 shown in the drawing has elasticity and is provided so as to be able to protrude and retract in the radial direction of the rotor piston 20, and the height dimension h in the protruding and retracting direction is the width t.
It is formed larger than. The height h in the protruding and retracting direction is the cylinder 3 at the center of rotation of the rotor piston 20.
When the amount of eccentricity of the blade 23 with respect to the rotation center is d, and the minimum engagement depth of the blade 23 with the blade groove 21 is l, h
= 2d + 1.

In the fluid compressor of the present invention, the helical blade 15 formed of an elastic body is protruded and retracted in the blade groove 14 while being deformed.
Therefore, a frictional force acts between the blade 15 and the blade groove 14.

If the relationship between the width dimension t of the blade 15 and the height dimension h in the protruding and retracting direction is h <t, the tension in the radial direction is weak. There is a problem in that the spiral blade 15 does not come out as it enters, and the outer dimensions of the spiral blade 15 are reduced, so that the sealing property between the operation chambers is impaired and compression becomes impossible.

However, in the present invention, as described above, since the relationship between the width dimension t of the blade 15 and the height dimension h in the protruding and retracting direction is configured as t <h, the spiral blade 15 is made of an elastic material. The radial tension can be increased while the blade 15
Can reliably protrude and retract with respect to the blade groove 14 to improve the sealing property between the operation chambers, thereby providing a fluid compressor with high compression efficiency.

Note that the present invention is not limited to the above embodiment.

〔The invention's effect〕

(1) By reducing the pitch of the blade at the suction side end within one turn, the blade at the suction side can be reliably pressed against the inner peripheral surface of the cylinder, and gas leakage can be reduced.

(2) By making the width t of the blade larger than the height h in the protruding and retracting direction, the rigidity of the blade is increased, and the pressure difference generated between the working chamber formed between the cylinder and the rotor piston is reduced. On the other hand, it is difficult to deform and gas leak can be prevented.

[Brief description of the drawings]

FIGS. 1 and 2 show a first embodiment of the present invention.
FIG. 1 is a side view showing a state in which a blade groove is provided in a cylinder, FIG. 2 is a side sectional view showing an arrangement of blades located on a suction side, and FIG. 3 is a conventional structure corresponding to FIG. FIG. 4 is a side sectional view showing a main part of a second embodiment of the present invention, FIGS. 5 to 7 are conventional examples, and FIG. 5 is a side sectional view of a fluid compressor. FIG. 6 is a side sectional view showing an inner portion of the cylinder, and FIG. 7 is a side view showing a state where blade grooves are provided with respect to a rotor piston. 2 ... closed container, 5 ... stator, 4 ... rotor, 3 ...
Cylinder, 8 ... suction port, 10 ... discharge port, 20 ... rotor piston, 21 ... blade groove, 22 ... small pitch groove,
23 ... Blade.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F04C 18/344 311 F04C 18/107

Claims (2)

(57) [Claims] 1. A cylinder comprising a hollow cylindrical body, a cylindrical piston eccentrically arranged in the cylinder, and a spiral formed on the peripheral surface of the piston so that the pitch decreases from the suction side to the discharge side. A plurality of working chambers between the piston and the cylinder. A fluid compressor characterized by forming a pitch groove. 2. A cylinder comprising a hollow cylindrical body, a columnar piston eccentrically arranged in the cylinder, and a spiral formed on the peripheral surface of the piston so that the pitch decreases from the suction side to the discharge side. And a blade which is fitted in the groove so as to be able to protrude and retract to form a plurality of operation chambers between the piston and the cylinder. The cross-sectional shape of the blade has a height h in the protruding and retracting direction. A fluid compressor formed in a rectangular shape larger than a width dimension t.