JP3307100B2 - Rotary 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 positive displacement machine, and more particularly to a rotary compressor for a refrigerating cycle of a refrigerator or an air conditioner.

[0002]

2. Description of the Related Art As described in Japanese Utility Model Laid-Open No. 5-47477, for example, a conventional rotary compressor inserts a crankpin portion into the inner periphery of a roller and revolves the roller by rotating a crankshaft. As a result, the roller and the crank pin portion slide directly.

[0003]

In the prior art, since the roller and the crank pin portion slide directly, a contact between the roller inner portion and the outer periphery of the crank pin portion due to an error in the degree of parallelism or an assembly error, etc. There was a problem that occurs.

[0004] It is an object of the present invention to suppress a one-sided contact occurring at a crank pin portion in a rotary compressor and eliminate a severe sliding portion.

[0005]

Means for Solving the Problems] To achieve the above object, the present invention is roller, contact the outer peripheral surface and a cylindrical outer peripheral surface of the crank pin part abutting against the cylindrical inner peripheral surface of B over La via a floating bushing having a circular <br/> cylindrical inner peripheral surface, and a structure for rotatably supporting the click Rankupin portion, the axial length of the contact portion between the roller inner peripheral surface of the outer peripheral surface of the floating bush , rather smaller than the axial length of the click Rankupin portion, the outer periphery of the floating bush
The inner circumference of the roller corresponding to the keyway of the floating bush
With keyways, each keyway has a roller and a floating bush
That having a key to prevent relative rotation of the Interview.

[0006]

With the structure in which the inner peripheral surface of the roller and the outer peripheral surface of the crank pin portion slide directly as in the prior art, there is a problem that a one-sided contact occurs in the crank pin portion depending on the precision of the parts. However, it means for solving this problem, Clan
Kupyn portion the roller, via a floating bushing having an outer peripheral surface and a cylindrical inner peripheral surface in contact with the cylindrical outer peripheral surface of the crank pin part abutting against the cylindrical inner peripheral surface of the roller, the structure of rotating supports, Since the axial length of the contact portion between the outer peripheral surface of the floating bush and the inner peripheral surface of the roller is smaller than the axial length of the crank pin portion, both ends of the outer peripheral sliding portion of the floating bush must be cranked. It can be arranged inside the axial length of the pin part. In other words, the center of the force acting on the floating bush from the roller moves only up to both ends of the contact portion of the outer peripheral surface of the floating bush with the inner peripheral surface of the roller,
Therefore, the center of the force acting on the crankpin portion from the floating bush is always in the length of the crankpin portion in the axial direction, and the occurrence of one-sided contact of the floating bush on the crankpin portion can be suppressed. Also, the outer circumference of the floating bush
The axial length of the sliding part is calculated from the axial length of the crank pin part.
If the diameter is reduced, the contact between the outer circumference of the floating bush and the inner
The contact area is between the outer circumference of the crank pin and the floating bush.
Because it is smaller than the area of the contact part on the inner circumference, the coefficient of friction
Depending on the size relationship, the outer circumference of the floating bush, roller
Between the inner circumferences of
And the sliding conditions become severe, but the inner circumference of the roller and the floating
In order to prevent the outer circumference of the bush from sliding,
The relative rotation of the roller and the floating bush with respect to the line
This problem does not occur.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. 1 is a cross-sectional view showing a rotary compressor according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line II in FIG. 1, FIG. 3 is a perspective view of a floating bush in the first embodiment of the present invention, FIG. 4 is an explanatory view of the movement of each component in FIG. 2 when the compressor driving motor is rotated by 90 °,
FIG. 5 is an enlarged view of a pump portion in FIG. 1, and FIG. 6 is a sectional view of a pump portion of a conventional rotary compressor.

In the first embodiment of the present invention shown in FIGS. 1 to 5, the cylinder 1 has a cylindrical hole 1a at the center.
Are formed, and the first plate member 2 and the second plate member 3 are fixed by bolts 4 so as to close both ends thereof. At this time, the central axes of the holes 2b, 3b formed in the bosses 2a, 3a at the center of the first plate member 2, the second plate member 3 are aligned with the cylindrical hole 1 of the cylinder 1.
It is fixed so as to be coaxial with the central axis of a. The outer peripheral portion of the cylinder 1 to which the first plate member 2 and the second plate member 3 are fixed is fixed to the chamber 5. A stator 6 of a compressor driving motor is fixed to the chamber 5. The holes 2b and 3b have a crankshaft 7
Are supported by bearings, and the outer periphery of the rotor portion 8 fixed to the end of the crankshaft 7 is incorporated with a small gap into the inner periphery of the stator portion 6 to form a compressor motor. The crankshaft 7 is formed with a cylindrical crankpin portion 7a eccentric to the center axis of the crankshaft 7 at a position corresponding to the cylindrical hole 1a of the cylinder 1. A hollow cylindrical floating bush 10 is inserted into the inner periphery of the roller 9, and the roller 9 and the crank pin portion 7 are inserted.
The space between a is rotationally supported.

As shown in FIG. 3, the floating bush 1
0 is a cylindrical part 10a provided in the center part.
And a tapered portion 10b whose diameter decreases from both ends of the cylindrical portion 10a toward both ends of the floating bush 10. Further, as shown in FIG. 5, the axial length of the central cylindrical portion 10a is smaller than the axial length of the crankpin portion 7a. A key groove 10c is formed at one place on the outer periphery of the floating bush, and a key groove 9a is also formed at one place on the inner periphery of the roller corresponding to the key groove 10c. And the floating bush 10 are prevented from rotating relative to each other.

A vane 12 is integrally fixed at one place on the outer periphery of the roller 9 by a method such as integral molding or welding. At this time, two parallel planes of the vane 12 are parallel to the central axis of the roller 9. It is fixed so that it becomes. Outside the cylindrical hole 1a of the cylinder 1, a cylindrical hole 1b having a central axis parallel to the central axis of the cylindrical hole 1a is formed.
The cylinder center side of the cylindrical hole portion 1b and the opposite side communicate with the cylindrical hole portion 1a and another space 13 provided outside the cylindrical hole portion 1b, respectively. The vane 12 is inserted into the cylindrical hole 1b and the space 13;
b, a sliding member 14 having a flat portion slidably in contact with the flat portion of the vane 12 and a cylindrical outer peripheral surface slidably in contact with the cylindrical inner peripheral surface of the cylindrical hole portion 1b is provided with the vane 12.
, And as a result, vane 1
Numeral 2 is supported by the cylinder 1 so that the cylindrical hole portion 1b can advance and retreat in the central axis direction and swing motion around the central axis. The tip of the vane 12 on the opposite side of the joint with the roller 9 moves in the space 13 and does not interfere with the cylinder 1.

With this configuration, when the rotor section 8 of the compressor driving motor rotates, the crankshaft 7 fixed thereto also rotates. Accordingly, the crank pin portion 7a formed eccentrically to the crank shaft 7 also rotates, and the roller 9 rotatably supported via the floating bush 10 is rotated.
Is given a revolving motion. Although FIG. 4 shows this to movement of the vane 12 which is integral with the roller 9 when the rotor 8 of the motor for driving the compressor is rotated by 90 °, b
The crankshaft 7 so that the vane 12 integrated with the roller 9 always faces the center line of the cylindrical hole 1b of the cylinder.
The roller 9 revolves around the center of the roller 9 while performing a swinging motion at a slight angle in the plane of FIG. The vane 12 is the cylindrical hole 1 of the cylinder 1
b, a reciprocating motion in a direction perpendicular to the central axis and a oscillating motion about the central axis.
The seal in the gap between the sliding member 14 and the sliding member 14 is maintained by inserting the sliding member 14 with the vane 12 interposed therebetween. Therefore, a compression chamber, which is a closed space, is formed by the cylinder 1, the roller 9, the vane 12, and the first plate member 2 and the second plate member 3, and the rotor portion 8 of the compressor driving motor is formed.
With the rotation of, the volume is repeatedly increased and decreased as shown in FIG.

A first side chamber 15 and a second side chamber 16 are welded to the openings at both ends of the chamber 5 to form a closed container as a whole. Working gas is suction port 1
After flowing into the compressor from 7 and passing through a suction passage 1 c formed in the cylinder 1, it is compressed in the compression chamber by increasing or decreasing the volume of the compression chamber, and a discharge port (not shown) formed in the second plate member 3. Then, the gas is discharged through the discharge valve 18 and the discharge valve retainer 19. After that, it flows out of the compressor through a discharge port 20 provided in the second side chamber 16 through the motor chamber.

In this embodiment, since the roller 9 and the vane 12 are integrated, the roller and the vane separate from each other as compared with the roller 21 and the vane 22 of the conventional structure shown in FIG. This eliminates the need for the preload spring 23 and the back pressure, which have been required to prevent the occurrence of the pressure. Further, in the structure shown in FIG. 6, the contact portion between the tip of the vane 22 and the outer periphery of the roller 21 and the contact portion between the vane 22 and the slit portion of the cylinder 24 are in linear contact or close contact therewith. While the localized concentrated load acts on the contact portion by the pressure of the compressed gas directly acting on the vane 22, in the present embodiment, the pressure of the compressed gas directly acting on the vane 12 is controlled by the cylinder via the sliding member 14. The first cylindrical hole 1b and the crankpin 7a of the crankshaft 7 via the floating bush 10 support it, and all can be supported by surface contact. That is, the sliding surface pressure of the sliding portion around the vane 12 is greatly reduced as compared with the conventional structure, and the durability can be improved.

Next, when a structure in which the roller 9 and the vane 12 are integrated is employed, the inclination of the integral member about the axis in the direction of the vane advance / retreat movement is caused by the flat portion of the sliding member 14 and the crank supporting the roller 9. The two constrained portions are simultaneously constrained to the cylindrical surface of the pin portion 7a, and it is difficult for the two constrained portions to come into close contact at the same time due to errors in the processing accuracy of the components. This is likely to cause a problem of reduced durability and an inability to assemble. However, in the present embodiment, the outer peripheral surface of the floating bush 10 inserted between the roller 9 and the crank pin portion 7a has the cylindrical portion 10a at the center and the floating bush 10 from both ends of the cylindrical portion 10a. It is composed of a tapered portion 10b whose diameter decreases toward both ends, and the axial length of the central cylindrical portion 10a is smaller than the axial length of the crankpin portion 7a. Both ends of the sliding portion can always be arranged inside the axial length of the crank pin portion 7a. That is, the roller 9
, The center of the force acting on the floating bush 10 moves at most only to both ends of the central cylindrical portion 10a of the floating bush 10, and therefore, the center of the force acting on the crank pin portion 7a from the floating bush 10 is always Crank pin part 7a
, The inclination of the integral member of the roller 9 and the vane 12 about the axis in the reciprocating motion direction of the vane 12 is not restricted by the cylindrical surface of the crankpin portion 7a, and the sliding member Thus, the above-mentioned problem due to excessive constraint does not occur.

When the axial length of the central cylindrical portion 10a on the outer peripheral surface of the floating bush 10 is smaller than the axial length of the crank pin portion 7a, the area of the contact portion between the outer circumference of the floating bush 10 and the inner circumference of the roller 9 is considered. However, since the area of the contact portion between the outer circumference of the crank pin portion 7a and the inner circumference of the floating bush 10 is smaller, the outer circumference of the floating bush 10 and the inner circumference of the roller 9 slide depending on the magnitude of the friction coefficient. Although the contact area decreases and the surface pressure increases due to the reduction of the contact area, the sliding conditions become severe. However, in the present embodiment, the sliding of the inner circumference of the roller 9 and the outer circumference of the floating bush 10 is fixed by the key 11 and the crank 11 Since the rotation about the axis of the pin portion 7a is prevented, this problem does not occur.

Furthermore, as in the second embodiment of the present invention shown in FIG. 7, even if the floating bush 10 of the present invention is employed in a conventional structure in which the roller 21 and the vane 22 are separate bodies, One side contact of the outer peripheral surface of the portion 7a can be prevented.

[0017]

According to the present invention, a rotary compressor having high durability can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a rotary compressor according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II in FIG.

FIG. 3 is a perspective view of a floating bush according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of the movement of each component in FIG. 2 when the motor for driving the compressor is rotated by 90 °.

FIG. 5 is an enlarged view of a pump portion in FIG.

FIG. 6 is a sectional view of a pump portion of a conventional rotary compressor.

FIG. 7 is a sectional view of a pump portion of a rotary compressor according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cylinder, 1a ... Cylindrical hole, 1b ... Cylindrical hole, 1
c ... suction passage, 2 ... first plate member, 2a, 3a ... boss portion, 2b, 3b ... hole portion, 3 ... second plate member, 4 ...
Bolt, 5: Chamber, 6: Stator, 7: Crankshaft, 7a: Crankpin, 8: Rotor, 9 ...
Rollers, 9a, 10c: keyway, 10: floating bush,
10a: cylindrical portion, 10b: tapered portion, 11: key, 12
... Vane, 13 ... Space, 15 ... First side chamber, 1
6 ... second side chamber, 18 ... discharge valve, 19 ... discharge valve holder, 20 ... discharge port.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-81991 (JP, A) JP-A-5-164071 (JP, A) JP-A-62-178499 (JP, A) JP-A-6-78499 221287 (JP, A) JP-A-5-202874 (JP, A) JP-A-63-73594 (JP, U) JP-A-63-136285 (JP, U) JP-B-2-8158 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) F04C 21/00 F04C 29/00

Claims (1)

(57) [Claims] 1. A cylinder having a cylindrical inner peripheral surface, a plurality of side plates closing both ends of the cylindrical inner peripheral surface of the cylinder, and a space surrounded by the cylinder and the plurality of side plates. a crankshaft providing a roller having the cylindrical outer peripheral surface is revolves while maintaining infinitesimal gap with the cylindrical inner peripheral surface of the cylinder, the revolving motion to the rollers in the cylinder of said cylinder A vane that further partitions the enclosed space surrounded by the inner peripheral surface of the roller, the cylindrical outer peripheral surface of the roller, and the plurality of side plates into a plurality of enclosed spaces. In a rotary compressor that compresses a gas by utilizing the change in the volume of each space, the roller includes an outer peripheral surface that contacts the cylindrical inner peripheral surface of the roller and the clutch. The rotating bush is rotatably supported by the crank pin portion via a floating bush having a cylindrical inner peripheral surface that comes into contact with the cylindrical outer peripheral surface of the crank pin portion of the crank shaft, and the outer peripheral surface of the floating bush contacts the roller inner peripheral surface. the axial length of the contact portion, the rather small <br/> than the axial length of the crank pin portion, the outer peripheral surface and its floating bush of the floating bushing
A key groove is provided on the inner peripheral surface of the roller corresponding to the key groove of
Each keyway with a roller and floating bush
A rotary compressor provided with a key for preventing an excessive rotation .