JPS60209689A - Vane compressor - Google Patents

Abstract

PURPOSE:To prevent generation of chattering of a vane by a method wherein the shape of a cam ring, capable of reducing remarkably an acceleration in the in-and-out direction of the vane at a joint in the edge of a reference cam curve, is adopted. CONSTITUTION:The shape of inner peripheral surface of a cylinder for the compressor is designed so that respective half sides of the reference cam curve, which are divided by the shorter diameter, are placed in eccentric by lengths (h) from the center O of a circle 62 in parallel to the shorter diameter into opposing directions and one end sections of the opposite side are intersected with the circle 62 at points A, A' while the other end sections are intersected with the circle 62 at the points B, B'. Further, the inner peripheral surface of the cylinder is defined by the circle 62 at the side which is intersecting with the circle 62.

Description

Detailed Description of the Invention Technical Field The present invention relates to a vane compressor in which a plurality of vanes that are in sliding contact with the inner circumferential surface of a cylinder are rotated as a rotor rotates, and particularly relates to a vane compressor in which the inner space of the cylinder is divided into two chambers by the rotor. This relates to a type of vane compressor in which gas is compressed in parallel in these two chambers.

A prior art vane compressor generally includes a cylinder, a rotor that is rotated within the cylinder, and a plurality of vanes that are held by the rotor and rotate together with the rotor and that are in sliding contact with the inner circumferential surface of the cylinder. One type of cylinder is one in which the internal space of the cylinder is divided into two chambers by a rotor, and the gas is compressed in parallel in these two chambers.

In this type of vane compressor, the cross-sectional shape of the inner peripheral surface of the cylinder is an elliptical reference cam curve so that the vane can easily follow the inner peripheral surface of the cylinder. A standard cam curve is formed by concentrically combining circles with a diameter larger than the short axis of the reference cam curve. The rotor is placed in substantial surface contact with the portion of the inner peripheral surface of the cylinder defined by the above-mentioned circle via lubricating oil, etc., thereby improving the airtightness between the cylinder and the rotor.

However, in a vane compressor where the cross-sectional shape of the inner peripheral surface of the cylinder is a combination of an elliptical reference cam curve and a circle, the acceleration of the vane in the direction of entering and exiting from the rotor outer peripheral surface is different from the reference cam curve. As a result, the vane cannot follow the inner circumferential surface of the cylinder at that joint, creating an area where the vane tip edge separates from the cylinder inner circumferential surface, or the vane tip edge repeating on the cylinder inner circumferential surface. There was a problem that caused chattering, which was caused by collision and produced a tapping sound. Conventionally, as mentioned above, the centers of the reference cam curve and the circle combined with it were made to coincide, so there were four joints on the inner peripheral surface of the cylinder, and such a phenomenon The frequency of occurrence was high. It has also been proposed to smoothly connect the reference cam curve and the circle with a special curve in order to reduce the knocking noise when the vane tip separates from the inner peripheral surface of the cylinder or comes into contact with it. Even if the vanes are connected to each other, it is unavoidable that the acceleration of the vanes will increase to some extent at the joints.

OBJECT OF THE INVENTION The present invention has been made against the background of the above-mentioned circumstances, and its object is to provide a cylinder including a cylinder, a rotor, and a plurality of vanes as described above. The cross-sectional shape of the inner circumferential surface consists of a combination of an elliptical reference cam curve and a circle having a diameter larger than the short axis of the reference cam curve, and the rotor is substantially located on the portion of the cylinder inner circumferential surface defined by the above-mentioned circle. In a vane compressor that has surface contact with
It is an object of the present invention to provide a vane compressor that can suppress chattering of the vanes as much as possible by reducing the chance that the acceleration in the direction of ingress and egress of the vanes becomes significantly large.

Structure of the Invention In order to achieve such an object, in the vane compressor according to the present invention, the portions of the reference cam curve located on both sides of its own minor axis are moved in the direction parallel to the minor axis thereof. are eccentric from the center to opposite sides so that one end touches the circle and the other end intersects with the circle, so that the inner circumferential surface of the cylinder is defined by the circle on the intersecting side.

Effects of the Invention By configuring the vane compressor in this way, the acceleration in the direction of vane entry and exit at the joint portion where the end of the reference cam curve is in contact with the circle is significantly reduced, and the vane smoothly moves through this joint portion. pass. As a result, the part where the acceleration becomes particularly large is limited to the part where the end of the reference cam curve intersects with the circle. In other words, in the part where the end of the reference cam curve is in contact with the circle, the separation of the vane from the cylinder inner circumferential surface is well prevented, which reduces the chance of reduction in compression efficiency and occurrence of chattering. It will decrease.

Moreover, in the present invention, since the separation of the vanes is effectively prevented in the portion where the end of the reference cam curve is in contact with the circle, the separation of the vanes is prevented in the circumferential direction of the rotor as in the conventional case. This eliminates the occurrence of chattering due to the occurrence of chattering in close proximity to each other. In other words, in a conventional vane compressor in which the center of the reference cam curve and the circle combined with it are aligned, two of the four joints between the reference cam curve and the circle are aligned in the circumferential direction of the rotor. Because they are formed close to each other, depending on the operating conditions of the compressor, the effects on the vanes of the two joints that are close to each other may overlap.
In such cases, chattering is particularly likely to occur, but according to the present invention, as described above, it is possible to prevent joints from forming close to each other in the circumferential direction of the rotor, thereby reducing the effects of such chattering. This makes it possible to avoid the harmful effects of overlapping.

EMBODIMENTS Hereinafter, embodiments in which the present invention is applied to a vane compressor for compressing refrigerant gas installed in an automobile as a vehicle cooling system will be described with reference to the drawings.

In FIGS. 1 and 2, 2 is a cylinder whose openings at both ends are closed by a front side plate 4 and a rear side plate 6, respectively. A front housing 8 is provided on the front side (left side in FIG. 1) of the front side plate 4 to form a suction chamber 10, in which refrigerant gas such as Freon gas returned from the external circulation circuit passes through a suction port 12 and is sucked into the suction chamber 10. It is guided to a chamber 1o, and is sucked into the cylinder 2 from this suction chamber 10. On the other hand, the rear housing 14 is connected to the front housing 8 while holding the cylinder 2 and both the front and rear side plates 4.6 inside. An oil separation chamber 18 is formed on the rear side of each. The refrigerant gas compressed in the cylinder 2 is led from the discharge chamber 16 through the communication hole 2o to the oil separation chamber 18, and an oil filter 2 provided therein is introduced.
After the lubricating oil present in a mist form is separated from the gas at step 2, the gas is delivered to the external circulation circuit through the discharge port 24. Note that the lubricating oil separated by the oil filter 22 is stored in a liquid state at the bottom of the oil separation chamber 18. In addition, the above-mentioned front and rear housings 8, 1
4 are tightened together by bolts 28 shown in FIG. 2, and constitute a housing for the entire compressor.

The cylinder 2 has an inner circumferential surface 30 having a substantially elliptical cross-sectional shape, and has a cylindrical cylinder inside that separates the internal space of the cylinder 2 into a first chamber 32 and a second chamber 34. A rotor 36 is housed therein.

The rotor 36 includes shafts 38 and 40 protruding from both end faces, and these are rotatably supported by the rear side plate 6 and the front side plate 4 via bearings 42. Further, the shaft 40 is projected to the outside of the front housing 8 while being sealed by a shaft sealing device 43, and can be connected to a drive source at this projecting end 6).

The rotor 36 also includes, as shown in FIG.
Four vane grooves 44 parallel to the axis are formed at equal angular intervals. Vanes 46 are slidably fitted into these vane grooves 44, respectively, and are held so as to be movable in and out of the outer peripheral surface 48 of the rotor 36 in the radial direction. The tip edges of the vanes 46 are moved by the elastic force of springs (not shown) acting on the back surface of the vanes 46, the oil pressure in the oil separation chamber 18, the centrifugal force accompanying the rotation of the rotor 22, etc. The cylinder 2. The volume of the space defined by the rotor 36 and the vane 4G increases once in the first chamber 32 and the second chamber 34, respectively, and then decreases.

On the other hand, in the first chamber 32 and second chamber 34 of the cylinder 2,
A suction hole 52 and a discharge hole 54 are provided at positions corresponding to the volume increase process and the volume decrease process of the space, respectively. As the rotor 36 rotates, the refrigerant gas in the suction chamber 10 is sucked into the space through the suction holes 52, compressed, and then discharged from the discharge hole 54 into the discharge chamber 16. There is. In other words, rotor 3
6 is rotated, the suction, compression, and discharge strokes of the refrigerant gas are repeated in the first chamber 32 and the second chamber 34, respectively, and compression work is performed in parallel in the compartments 32 and 34. Note that each of the discharge holes 54 is provided with a reed-type discharge valve 56, and the lift amount thereof is regulated by a holding plate 58.

In the compressor described above, as the rotor 36 rotates, each vane 46 moves in and out of the rotor outer circumferential surface 48 due to a change in the distance between the rotor outer circumferential surface 48 and the cylinder inner circumferential surface 30, and moves around the cylinder inner circumference. In this case, in order to maintain high compression efficiency and suppress chattering of the vanes 46, the ability of each vane 4G to follow the cylinder inner circumferential surface 30 is as high as possible. This is desirable. On the other hand, in order to maintain high compression efficiency, it is necessary to improve the airtightness between the cylinder 2 and the rotor 36.
8 is preferably in substantial surface contact.

Therefore, in this embodiment, the inner peripheral surface 3 of the cylinder 2 is
0 is shaped as shown in FIG. The acceleration in the direction of entry and exit is reduced as much as possible.

That is, as shown in FIG. 3, the cylinder inner circumferential surface 30 basically has a shape that is a combination of an elliptical reference cam curve 60 and a circle 62 whose diameter is larger than its short axis. , each side of the reference cam curve 60 separated by the minor axis is a circle 62 parallel to the minor axis and in opposite directions.
are offset by h from the center O, and one end of each of them touches the circle 62 at points A and A', respectively, and each other end touches the circle 62 at points B and B', respectively.
2 (more precisely, the vicinity of this intersection is smoothly connected with another curve), and on the side where it intersects with the circle 62, the cylinder inner circumferential surface 30 crosses the circle 62.
2. Then, the rotor 36 is inserted into the cylinder 2 in a state in which it is in surface contact with the portion of the cylinder inner circumferential surface 30 defined by the inner part 62 (arc AB'', A'B portion) via the lubricant. In this embodiment, as is clear from FIG. Each other end intersects the circle 62 on the near side.

In this way, in this embodiment, the cylinder inner circumferential surface 30 and the rotor outer circumferential surface 48 are brought into substantially surface contact at the portion that divides the space inside the cylinder 2 into the first chamber 32 and the second chamber 34. The airtightness between the first chamber 32 and the second chamber 34 is maintained well, and as a result, the compression work efficiency in each chamber 32, 34 is maintained at a high level. Also, one end of each side of the reference cam curve 60 opposite to each other is a circle 62.
Therefore, in these parts, the transition of the vane 46 from the circle 62 to the reference cam curve 60 is performed smoothly, and the acceleration in the in/out direction at the time of the transition is suppressed to a small value, and as a result, Those reference cam curves 6
The ability of the vane 46 to follow the cylinder inner circumferential surface 30 at the contact portion between 0 and the circle 62 is improved, and the separation of the vane 46 from the cylinder inner circumferential surface 30 is well suppressed, improving compression efficiency and reducing chattering. occurrence is avoided.

Moreover, since the separation of the vanes 46 at the portion where the reference cam curve 60 and the circle 62 touch is well suppressed, the acceleration of the vanes 46 does not become particularly large at positions close to each other in the rotor circumferential direction. , the harmful effects caused by the superimposition of their effects are also eliminated. In addition, since the occurrence of chattering is suppressed, the life of the vane 46 is increased, and furthermore, it is possible to reduce the urging force that urges the heel 746 against the inner circumferential surface of the cylinder. It is possible to reduce wear on the peripheral surface 30 and to suppress power loss due to the frictional force between the two.

Incidentally, in FIG. 4, a solid line C shows the relationship between the sliding position of the vane 46 and the acceleration in the pop-out direction in this embodiment, and a conventional compression curve in which the centers of the reference cam curve 60 and the circle 62 are made to coincide with each other. As is clear from this figure, in the conventional compressor, the acceleration of the vane 46 is large at two adjacent points, but in this embodiment, the acceleration of the vane 46 is large at two points close to each other. The acceleration of the vane 46 is suppressed to be extremely low at points A and A' where the vanes 46 and 46 are in contact with each other. In addition,
In the same figure, the rotational positions of the rotor 36 indicated by E and F indicate the intersection of the reference cam curve 60 and the circle 62 forming the inner circumferential surface of the cylinder of the conventional pressurizing machine (Fig. 3), and
The one-dot chain line shown by the dashed line indicates the acceleration when the inner circumferential surface of the cylinder is formed by the reference cam curve 60 (L).

Although one embodiment of the present invention has been described above, this is literally an illustration, and the present invention is not interpreted as being limited to the above embodiment.

For example, in the embodiment described above, one end of each side of the reference cam curve 60 touches the circle 62 on the side closer to the suction hole 52, and each other end intersects with the circle 62 on the side closer to the discharge hole 54. However, the reference cam curve 60 and the circle 62 may touch on the side closer to the discharge hole 54 and intersect on the side closer to the suction hole 52.

Further, in the embodiment described above, four vanes 46 were provided on the rotor 36, but the number can be increased or decreased as appropriate. Furthermore, the present invention is not limited to vane compressors for vehicle interior cooling systems, but can also be applied to vane compressors for other uses.

In addition, although not listed here, the present invention may be modified without departing from its spirit and based on the knowledge of those skilled in the art.
Of course, it can be implemented in an improved manner.

[Brief explanation of the drawing]

FIG. 1 is a front view (I-'I cross-sectional view in FIG. 2) of a vane compressor that is an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line ■--■ in FIG. 1. FIG. 3 is an explanatory diagram for explaining the shape of the inner circumferential surface of the cylinder in the compressor shown in FIG. 1, and FIG. It is a graph shown in comparison with a compressor. 2 Niji cylinder 30 Niji cylinder inner circumferential surface 32: Second chamber 34: Second chamber 36: Rotor 46: Vane 48: Rotor outer circumferential surface 52: Suction hole 54: Discharge hole 60: Reference cam curve 62: Yen applicant Toyota Jidosha Co., Ltd. Loom Factory G2 Diagram 3

Claims (1)

[Scope of Claims] The cylinder includes a cylinder, a rotor that is rotated within the cylinder, and a plurality of vanes that are held by the rotor and rotate together with the rotor and that are in sliding contact with the inner circumferential surface of the cylinder; The cross-sectional shape of the inner circumferential surface is made up of a combination of a reference cam curve having an elliptical shape and a circle having a diameter larger than the short axis of the reference cam curve, and the rotor is substantially attached to a portion of the inner circumferential surface of the cylinder defined by the circle. In a vane compressor in which surface contact is made between surfaces, the portions of the reference cam curve located on both sides of its own minor axis are eccentrically moved from the center of the circle to opposite sides in a direction parallel to the minor axis thereof, and one end A vane compressor, characterized in that one end touches the circle, the other end intersects with the circle, and the inner circumferential surface of the cylinder is defined by the circle on the intersecting side.