JP3110831B2 - Fluid compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Reciprocating compressors, rotary compressors and the like are generally known as conventional compressors. In addition, refrigerant flowing into a working chamber from a suction end side of a cylinder is discharged to a discharge end side of the cylinder. The spiral type fluid compressor which compresses while sequentially transferring the fluid to the working chamber and discharges the fluid to the outside is provided.

[0003] An outline of a spiral type compressor is shown in FIG.
And a cylinder 105 rotated by a driving means including a stator 101 and a rotor 103 as shown in FIG.
05 and placed eccentrically by e
And a rotating rod 109 that can rotate relative to the cylinder 105 through the shaft.
08 and 108 are rotatably supported at both ends by a main bearing 110 and a sub-bearing 110. A helical groove 111 is formed on the outer peripheral surface of the rotating rod 109 over substantially the entire length of the rod 109, and a helical blade 113 is fitted in the groove 111 so as to be able to enter and exit. The outer peripheral surface of the blade 113 is in close contact with the inner peripheral surface of the cylinder 105, and the blade 113 rotates integrally with the rotating rod 109. A part of the outer peripheral surface of the rotating rod 109 for the cylinder 105 is
5 is eccentrically rotated while being in line contact with a part of the inner peripheral surface of blade 5, so that blade 113 enters and exits helical groove 111, and a plurality of working chambers 115 are provided in the space between rotating rod 109 and cylinder 105. Are formed along the axial direction. The volume of the working chamber 115 is determined by the pitch P of the spiral groove 111 into which the blade 113 is fitted as shown in FIG.
From one end to the other end. Accordingly, the volume of the working chamber 115 formed by the blade 113 gradually decreases from the suction end side of the rotary rod 109 on the suction pipe 117 side to the discharge end side on the discharge pipe 119 side. It is configured to be compressed and discharged to the outside while being sequentially transferred to the discharge end side.

[0004]

As described above, in the helical fluid compressor, the working chamber 115 is formed by blades 113 having different pitches P, and the volume when the refrigerant is confined in the working chamber 115 and the discharge volume Working chamber 1 just before
The volume of 15 is mechanically determined, and the discharge pressure is determined by the suction pressure. For this reason, for example, when the operating conditions change due to an external factor and a refrigerant or lubricating oil exceeding a specified amount is taken into the working chamber 115, an overcompression state occurs, and an excessive load acts on the bearing portion and the blade. And had problems such as uneven wear and damage.

Accordingly, an object of the present invention is to provide a highly reliable fluid compressor which avoids overcompression at the time of abnormality.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a cylinder and an eccentrically mounted cylinder.
Circle which is arranged in a state where it can be turned relative to the cylinder
Columnar rotating body, and axial direction of the rotating body and the cylinder
A bearing for rotatably supporting both support shafts,
Provided on the outer periphery of the rolling element, from the suction side to the discharge side of the cylinder
A spiral groove formed at a gradually decreasing pitch to
The groove is inserted into and out of this groove so that it can be freely inserted into and out of the cylinder.
An outer peripheral surface that is in close contact with the peripheral surface;
A spiral blade that partitions the space into a plurality of working chambers
In the fluid compressor, the bearing is provided with an urging member for urging both support shaft portions of the rotating body to be positioned at an eccentric position, and both the bearings which move backward against the urging force of the urging member are provided. The direction of movement of the shaft is defined as a rear position deviated from a center axis connecting the rotation center of the cylinder and the rotation center of the rotating body.

[0007]

According to such a fluid compressor, when a refrigerant or the like exceeding a prescribed amount is taken into the working chamber, the working chamber is in an over-compressed state. Backward movement smoothly and smoothly against the biasing force of the biasing member at the rear position deviated from the center axis connecting the rotation center of the cylinder where the gas force pushes the rotating body and the rotation center of the rotating body And a large load does not act on both support shafts. Similarly, the rotating body at an eccentric position where a part of the rotating body is in contact with the inner peripheral surface of the cylinder comes away from the cylinder, and the seal between the working chambers is broken by the clearance created between the cylinder and the rotating body, The pressure at the time of overcompression is applied to the working chamber on the low pressure side (suction end side), so that a large load does not act on the blade, and no unreasonable operating state occurs.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS. In FIG. 1, 1
1 shows a closed case of a hermetic type fluid compressor 3 used for a refrigeration cycle. One of the closed cases 1 is provided with a suction pipe 5 for the refrigeration cycle, and the other is provided with a discharge pipe 7. An electric element 9 as a driving unit and a compression element 11 as a compression unit are arranged in the closed case 1.

The electric element 9 has a stator 13 fixed to the inner surface of the sealed case 1 and a rotatable rotor 15 provided inside the stator 13.

The compression element 11 has a cylinder 17 whose both ends are open. The cylinder 17 is rotatably supported at both ends by left and right main bearings 19 and auxiliary bearings 20 fixed to the inner surface of the sealed case 1. . The bearings 19 and 20 are bosses 19a and 20a in which the ends of the cylinder 17 are rotatably fitted.
And bases 19b and 20b which are larger in diameter than the bosses 19a and 20a and are fixed to the inner surface of the sealed case 1. Both ends of the cylinder 17 are airtightly closed.

Inside the cylinder 17, a cylindrical rotating body 21 smaller than the inner diameter of the cylinder 17 is arranged along the axial direction of the cylinder 17. The rotating body 21 is made of an iron-based or other material, and its central axis A is disposed eccentrically downward with respect to the central axis B of the cylinder 17 by a distance e in FIG. doing.

The amount of eccentricity e is D when the inside diameter of the cylinder 17 is D, the outside diameter of the rotating body 21 is d, and the cylinder 17 and the rotating body 21
E ≦ ( D−d ) / 2−
cl is set.

At both ends of the rotating body 21, spindles 21a and 21b having a small diameter are provided, respectively.
a and 21b are bearing holes 19c and 20c formed in the boss portions 19a and 20a of the main bearing 19 and the sub-bearing 20, respectively.
Is rotatably inserted and supported via a bush 22.

As shown in FIG. 2, the bearing holes 19c and 20c provided in each of the bosses 19a and 20a are formed in a vertically long cross-sectional rectangular shape and have a rotation center P of the cylinder 17 which rotates as shown by an arrow a. ₁ and deflection off the θ min rearwardly from the central axis W1 connecting the rotational center P ₂ of the rotary member 21 the axis W2
It is provided along the top.

The bush 22 is provided with the bearing holes 19c, 20c.
And a slide movement (arrow B) is possible along the deflection axis W2.

The bush 22 is biased by a biasing member 24 such as a leaf spring in the direction of deflection along the deflection axis W2. The biasing member 24 is disposed on the eccentric axis W2, and one end acts on the bosses 19a and 20a, and the other end acts on the bush 22. Thus, the two support shaft portions 21a and 21b of the rotating body 21 are positioned at eccentric positions (solid lines in FIG. 2) with respect to the cylinder 17.

On the other hand, a square column 25 having a square cross section which functions as a power transmission surface through which rotational power from the cylinder 17 is transmitted via an Oldham ring 23 is formed on the left support shaft 21a of the rotating body 21. ing. This prism 25
Has a play with the rectangular long hole 26 formed in the Oldham ring 23 and allows the prism 25 to slide within the range of the play. Also,
One end of a pair of transmission pins 27 is slidably fitted on the outer peripheral surface of the Oldham ring 23 in a radial direction orthogonal to the longitudinal direction of the long hole 26.
The other ends of the members 7 and 27 are fitted and fixed in fitting holes 29 formed in the peripheral wall of the cylinder 17. As a result, the rotating body 21 is securely connected at an eccentric position with respect to the cylinder 17, and the rotating force of the cylinder 17 is transmitted to the rotating body 21 through the Oldham ring 23. I have.

Accordingly, when the cylinder 17 rotates integrally with the rotor 15 by the operation of the electric element 9, the rotating body 21 eccentrically rotates with respect to the cylinder 17 via the Oldham ring 23 .

On the other hand, a spiral groove 31 is provided on the outer peripheral surface of the rotating body 21. The spiral groove 31 has the largest pitch P on the suction end side (left side in FIG. 1). The pitch is set so as to gradually decrease toward the discharge end side (right side in the drawing).

A helical blade 33 made of an elastic material such as a synthetic resin is fitted into the helical groove 31 so as to be able to move in and out by utilizing elastic force. This allows
Each of the working chambers 35 is formed, and the capacity of the working chamber 35 on the suction end side is the largest. Hereinafter, the volume of each working chamber 35 is set so as to gradually decrease toward the discharge end side, and the final working chamber 35 serving as the discharge side has a discharge hole opened in the closed case 1 formed in the auxiliary bearing 20. 37. Further, as shown in FIG. 5, each working chamber 35 is a substantially crescent-shaped region extending from the contact portion between the rotating body 21 and the inner peripheral surface of the cylinder 17 along the blade 33 to the next contact portion. The first working chamber 35 on the suction end side is
It is connected and connected to the suction pipe 5 of the refrigeration cycle via a main passage 39 provided at the shaft end of the rotating body 21 and a suction passage 41 provided in the main bearing 19. Thereby, the refrigerant sucked into the thin lid 17 from the suction pipe 5 is surely introduced into the first working chamber 35 without interruption.

In FIG. 1, reference numeral 43 denotes an oil introduction passage provided in the rotating body 21. One end of the oil introduction passage 43 communicates with the spiral groove 31, and the other end thereof is on the suction end side. Is connected to an inlet pipe 49 having a suction port 47 facing the bottom of the sealed case 1 through a communication hole 45 formed in the main bearing 19. Therefore, when the pressure in the closed case 1 rises, the lubricating oil stored in the bottom of the closed case 1 is fed into the groove 31 through the introduction pipe 49, the communication hole 45, and the oil introduction path 43, so that the blade The lubrication at the time of entry and exit of 33 is ensured.

Next, the operation of the fluid compressor configured as described above will be described.

First, when power is supplied to the electric element 9, the rotor 15
Rotates, and the cylinder 17 also rotates integrally with the rotor 15. When the cylinder 17 rotates, the Oldham ring 23
The rotator 21 also rotates via . Result of this, the fluid such as refrigerant taken into the working chamber 35 of the suction end is compressed while sequentially fed toward the working chamber 35 of the discharge end with the rotation of the rotating body 21 in a state of being confined, discharge Pipe 7
From the outside.

In this operation, for example, when a large amount of refrigerant or the like is taken into the working chamber 35 due to a change in operating conditions, the working chamber 35 is in an over-compressed state exceeding a specified pressure. When this overcompression state occurs, the pressure causes the two support shaft portions 21a and 21b to rotate from the central axis W1 against the urging force of the urging member 24 in combination with the rotational motion because the rotational motion is given. It escapes along the deviated displacement axis W2. For this reason, an unreasonable load acts on both support shaft portions 21a and 21b. At the same time, both support shafts 2
As a result of the escape of 1a and 21b, the rotating body 21 at an eccentric position, a part of which is in contact with the inner peripheral surface of the cylinder 17, separates from the cylinder 17 as shown by a chain line in FIG. The pressure at the time of overcompression escapes to the working chamber 35 on the low pressure side (suction end side). Therefore, a large load is not applied to the blade 33, and a smooth operating state is ensured.

As shown in FIG. 6, both support shafts 21a and 21b are provided with bearing holes 19c and 20c of bosses 19a and 20a.
While the rotation center P ₃ interpolating fitted rotatably by the bushing 22 which is offset β within, the stopper portion 5 extending from the bushing 22 into the rotary groove 51 provided in the bearing hole 19c
It is also possible to provide an urging member 55 for urging the stopper portion 53 in the direction of arrow C with the stopper 3 facing. Accordingly, when the inside of the working chamber 35 is in an over-compressed state, the bush 22 rotates in the direction indicated by the arrow D, so that the two support shaft portions 21a and 21b escape toward the eccentric axis line W2. For this reason, an unreasonable load does not act on both the support shaft portions 21a and 21b and the blade 33, and a stable operation state can be obtained.

[0026]

As described above, according to the fluid compressor of the present invention, even if an overcompression state occurs, it is possible to prevent an unreasonable load from acting on both the support shafts and the blades. As a result, a stable operating state can be obtained, and a great improvement in reliability can be expected.

[Brief description of the drawings]

FIG. 1 is a sectional view of a fluid compressor embodying the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory diagram showing a relative position between a cylinder and a rotating body.

FIG. 4 is a perspective view of a rotating body.

FIG. 5 is a sectional view taken along line BB of FIG. 1;

FIG. 6 is a sectional view similar to FIG. 2 showing a modification.

FIG. 7 is a sectional view similar to FIG. 1 showing a conventional example.

FIG. 8 is a perspective view of a rotating body showing a conventional example.

[Explanation of symbols]

 Reference Signs List 9 driving element (driving means) 17 cylinder 19 main bearing 20 sub bearing 21 rotating bodies 21a, 21b spindle 31 spiral groove 33 blade 35 working chamber 41 biasing member

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F04C 18/30-18/352 F04C 29/10 331

Claims (1)

(57) [Claims] Claims: 1. A cylinder and eccentric within the cylinder
A cylinder arranged in a state and capable of pivoting relative to the cylinder
Rotator, and both the rotator and the cylinder in the axial direction.
A bearing for rotatably supporting the support shaft,
From the suction side to the discharge side of the cylinder provided on the outer periphery of the body
Spiral grooves formed with a gradually decreasing pitch
The inner periphery of the cylinder
An outer peripheral surface closely contacting the surface between the cylinder and the rotating body
A helical blade for partitioning the rotor into a plurality of working chambers.The fluid compressor further comprises: a biasing member for biasing both spindle portions of the rotating body to the eccentric position by the bearing. In addition to the above, the moving direction of the two support shafts that retreats against the urging force of the urging member is set to a rearward position deviated from a center axis connecting the rotation center of the cylinder and the rotation center of the rotating body. Characteristic fluid compressor.