JPH036358B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a rotary compressor in which a rotary sleeve that rotates together with a rotor and vanes is floatingly supported in a center housing via an air bearing chamber. Concerning the structure of the sleeve.

[Prior Art] In general, rotary compressors have different performance requirements depending on their use, but vane-type rotary compressors are particularly suitable for use in automotive engine superchargers, etc., and are suitable for use at optimal high pressure and a wide range of rotational speeds. In order to obtain this, a rotating sleeve is provided between the center housing and the rotor,
A rotary compressor in which an air bearing chamber is formed between the outer circumferential surface of the rotary sleeve and the inner circumferential surface of the center housing, the rotary sleeve is supported in a floating manner, and the rotary sleeve is rotated together with a rotor and vanes has been previously described. It has been proposed by the present applicant (Japanese Unexamined Patent Publication No. 58-65988
(No. 58-28608). With this proposal, heat generation due to rotation and sliding of the vanes is suppressed, and
Floating support using air bearings provides smooth rotation without lubrication, resulting in a rotary compressor suitable for use at high pressures, large flow rates, and over a wide range of rotational speeds.

[Problems to be Solved by the Invention] However, in the above-mentioned rotary compressor, the inner circumferential surface of the rotary sleeve becomes high in temperature due to the heat generated due to the adiabatic compression of the intake gas, whereas the outer circumferential surface of the rotary sleeve is heated to a high temperature. Since the rotary sleeve is cooled by heat radiation from the housing and gas flow within the air bearing chamber, a temperature difference occurs between the inner and outer peripheral surfaces of the rotating sleeve. As a result, the rotating sleeve, which has both free ends, undergoes free thermal deformation into an hourglass shape. As a result, the clearance between the rotating sleeve, which requires high precision, and the center housing becomes uneven, and the clearance in the center of the rotating sleeve becomes particularly large, reducing the load force on the air bearing and impairing the performance of the air bearing. There is a risk. In addition, since both ends of the rotating sleeve warp outward, both ends of the rotating sleeve tend to come into contact with the inner peripheral surface of the center housing and the inner surface of the housing during rotation.
There is a risk that scuffing due to contact and wear of both ends of the rotating sleeve may occur, which may impede rotation of the rotating sleeve. Furthermore, since the entire rotating sleeve is at a higher temperature than the center housing, the clearance of the air bearing chamber becomes smaller due to the difference in thermal expansion.
The outer circumferential surface of the rotating sleeve may come into contact with the inner circumferential surface of the center housing, which may impede rotation of the rotating sleeve and may cause wear on the outer circumferential surface.

In order to solve the above-mentioned problems, the present invention, in a rotary compressor having a rotary sleeve floatingly supported by an air bearing, minimizes the thermal deformation of the drum-shaped rotary sleeve and provides sufficient clearance for the air bearing. The objective is to improve the wear resistance of the outer circumferential surface of the rotating sleeve, and to ensure smooth rotation performance due to the air bearing at all times.

[Means for Solving the Problems] A rotary compressor of the present invention that meets this objective has a rotary sleeve floatingly supported in a center housing via an air bearing chamber, and is inserted and inserted into the rotary sleeve so as to be freely removable. A rotary compressor equipped with a rotor having rotary vanes, wherein a layer of fiber-reinforced metal or fiber-reinforced resin having a coefficient of thermal expansion smaller than that of the base material of the rotary sleeve is provided on the inner and outer peripheral surfaces of the rotary sleeve. consists of things.

[Function] With this configuration, the layer of fiber-reinforced metal or fiber-reinforced resin with a small coefficient of thermal expansion suppresses the thermal expansion of the rotating sleeve base material from both the entire inner and outer surfaces of the rotating sleeve. Thermal deformation of the entire rotary sleeve and both ends is suppressed to a small level, and the drum-shaped thermal deformation of the rotating sleeve and the thermal expansion of the entire rotating sleeve are suppressed to a small level. Furthermore, since the layer with a low coefficient of thermal expansion is composed of fiber-reinforced metal and fiber-reinforced resin, the wear resistance and strength of the outer circumferential surface of the rotating sleeve are increased, and the rotation sleeve is Wear is prevented. moreover,
As a result of suppressing hourglass-shaped deformation, a uniform clearance in the air bearing chamber is maintained, local contact between both ends of the rotating sleeve is prevented, wear at both ends is suppressed, and thermal expansion of the entire rotating sleeve is suppressed. As a result, the proper clearance of the air bearing chamber is maintained, the load force of the air bearing is maintained, and the rotating sleeve is prevented from coming into contact with the housing. Effects can be obtained.

[Embodiments] Hereinafter, preferred embodiments of the rotary compressor of the present invention will be described with reference to the drawings.

1 to 4 show a rotary compressor according to a first embodiment of the present invention. In the figure, 1 is a center housing, 2 is a rotor provided in the center housing 1, and the rotor 2 is rotatably supported by bearings 4 and 5 on a rotating shaft 3 formed integrally with the rotor 2. ing. bearings 4, 5
are fitted into the front side housing 6 and the rear side housing 7, respectively. The front side housing 6, the rear side housing 7, and the rear cover 8 provided on the outside of the rear side housing 7 are fastened to the center housing 1 by bolts 9 passing through the center housing 1. The rotating shaft 3 of the rotor 2 is connected via a rotating member 12 to a pulley 11 rotatably supported by the front side housing 6 via a bearing 10. Rotational driving force is transmitted to the pulley 11 from a drive device (not shown), such as an engine crankshaft.

As shown in FIG. 2, the rotor 2 has an axis 14 located eccentrically from the axis 13 of the center housing 1. The rotor 2 is formed with a plurality of bottomed vane grooves 15 that extend in the radial direction of the rotor 2 and open toward the inner circumferential surface of the center housing 1. A vane 16 is fitted into the facing part so as to be freely removable and removable.

A rotating sleeve 17 made of an annular member having substantially the same axis as the axis 13 of the center housing 1 is rotatably installed between the vane 16 and the inner peripheral surface of the center housing 1 . A clearance between the outer peripheral surface of the rotating sleeve 17 and the inner peripheral surface of the center housing 1 forms an air bearing chamber 18 . The air bearing chamber 18 is formed over the entire outer peripheral surface of the rotary sleeve 17, and the rotary sleeve 17 has the air bearing chamber 1 in the center housing 1.
It is floatingly supported via 8. The air bearing chamber 18 has a gas inlet 19 and an outlet 2 formed in the inner peripheral surface of the center housing 1 in the shape of a straight slit extending parallel to the axis of the rotating sleeve 17.
0 is open. The opening of the inlet 19 may be a slit extending in a zigzag pattern or an isosceles triangular opening having an apex in the direction of rotation.

The inlet 19 is a gas supply hole 21 that is formed in the rear side housing 7 by being drawn around in the circumferential direction.
A discharge chamber 27 formed in the rear cover 8 via
It communicates with The discharge chamber 27 communicates with a discharge hole 29 formed in the rear side housing 7 via a discharge valve 28. The discharge hole 29 opens in an arc shape on the rotor 2 side and communicates with a discharge side working chamber 30 between the rotor 2 and the rotating sleeve 17, and communicates with the discharge side working chamber 30 between the rotor 2 and the rotating sleeve 17 through a communication hole 31 that opens in an arc shape on the rotor 2 side. It communicates with a space formed between the bottom of the vane groove 15 and the vane 16.

On the other hand, the outlet 20 is connected to the rear side housing 7.
It communicates with a suction chamber 22 formed within the rear cover 8 through a gas discharge hole 26 formed by extending it around in the circumferential direction. The suction chamber 22 is connected to a suction side working chamber 24 between the rotor 2 and the rotating sleeve 17 via a suction hole 23 formed in the rear side housing 7 and opened in an arc shape on the rotor 2 side as shown in FIG. It's communicating. The suction chamber 22 also communicates with a space formed between the bottom of the vane groove 15 and the vane 16 via a communication hole 25 that is opened in an arc shape on the rotor 2 side.

Note that the gas inflow port 19 and gas outflow port 20 are arranged in the rotational direction A of the rotor 2, as shown in FIG.
They are provided at the starting end and the ending end of the discharge side operating region.

Annular grooves 32 and 33 that open toward the rotation sleeve 17 are formed on the inner surfaces of the front side housing 6 and the rear side housing 7 that face both ends of the rotation sleeve 17.
33 is fitted with an annular, non-lubricated sliding member 34. The sliding member 34 is made of a carbon-based self-lubricating material.

The rotating sleeve 17 is made of light metal or light alloy such as aluminum or aluminum alloy.
3 and 4 on the inner and outer peripheral surfaces of 7.
As shown in the figure, aluminum or aluminum alloy is used as the base material 35
A layer 36 of fiber-reinforced metal or resin is provided. This fiber-reinforced metal or fiber-reinforced resin layer 36 is made of a material whose coefficient of thermal expansion is smaller than that of the base material 35 of the rotating sleeve 17. In this embodiment, the fiber-reinforced metal or fiber-reinforced resin layer 36 is formed by providing fibrous SiC, carbon, glass, etc. with a small coefficient of thermal expansion on the inner and outer peripheries of the rotating sleeve 17, and filling the holes with the rotating sleeve 17. Base material 35
It is made of fiber-reinforced metal infiltrated with. Note that this layer 36 is similar to the base material 35 of the rotating sleeve 17.
The inner peripheral surface and the outer peripheral surface may be made of a fiber-reinforced resin in which polyimide plastic is infiltrated into fibers such as SiC, carbon, or glass. The thickness t of the fiber-reinforced metal or fiber-reinforced resin layer 36 is as shown in FIGS. 3 and 4.
Although it is shown to be thick in the figure, it actually consists of a thin layer, usually 1 mm or less.

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

First, regarding the operation of the rotary compressor, driving force is transmitted from the engine etc. to the pulley 11, rotational force is transmitted to the rotor 2 via the pulley 11, the rotating member 12, and the rotating shaft 3, and the rotor 2 rotates. be done. As the rotor 2 rotates, the vanes 16 are pushed outward in the radial direction by centrifugal force and pressed against the inner peripheral surface of the rotating sleeve 17. By the rotation of the rotor 2 and the vane 16, the suction hole 2 is moved from the suction chamber 22 to the suction hole 2.
3, gas is sucked into the suction side working chamber 24. When the sucked gas reaches the discharge-side working chamber 30 as the rotor 2 rotates, it is compressed between the rotor 2 and the inner circumferential surface of the rotating sleeve 17, which gradually narrows in the rotational direction A. The compressed gas is discharged from the discharge chamber 27 through the discharge hole 29 . Between the vane 16 and the bottom of the vane groove 15,
Gas is sucked through the communication hole 25 so that the vane 16 can smoothly reciprocate within the vane groove 15.
In addition, gas is discharged through the communication hole 31.

Further, the rotating sleeve 17 rotates together with the vane 16 when the frictional force caused by sliding contact with the vane 16 becomes greater than the frictional force between the rotating sleeve 17 and the inner circumferential surface of the center housing 1 . Then, when gas is drawn into the air bearing chamber 18 through the inlet 19 and the rotating sleeve 17 is floatingly supported within the center housing 1 by the air bearing, the friction between the rotating sleeve 17 and the center housing 1 is drastically reduced.
Provides smooth rotation.

Since the gas inlet 19 is provided at the starting end of the discharge-side working region and the gas outlet 20 is provided at the terminal end of the discharge-side working region, the inner peripheral surface of the center housing 1 is particularly affected by the high pressure in the discharge-side working chamber 30. Gas is flowed into a portion of the air bearing chamber 18 corresponding to the discharge side region against which the rotating sleeve 17 is to be pressed.
A clearance between the rotating sleeve 17 and the center housing 1 in this region is ensured, and a good air bearing effect is exhibited.

Next, prevention of thermal deformation and improvement of wear resistance of the rotating sleeve 17 will be described. Working chambers 24, 30
Since gas is repeatedly sucked and compressed, heat generation occurs due to adiabatic compression, and the inner circumferential surface of the rotating sleeve 17 is exposed to a high-temperature atmosphere. On the other hand, the outer circumferential surface of the rotating sleeve 17 has a lower temperature than the inner circumferential surface because heat is removed from the center housing 1 and the gas flowing into the air bearing chamber 18 is constantly replaced. For this reason, a temperature difference occurs between the inner and outer circumferential surfaces of the rotating sleeve 17, and the amount of thermal expansion on the inner circumferential surface side tends to be larger than on the outer circumferential surface side, so the rotating sleeve 17, which has both free ends, deforms into an hourglass shape. try to. but,
Since the coefficient of thermal expansion of the fiber-reinforced metal or fiber-reinforced resin layer 36 provided on the inner and outer peripheral surfaces of the rotating sleeve 17 is smaller than that of the base material 35 of the rotating sleeve 17, Thermal expansion in the radial direction is suppressed by the fiber-reinforced metal or fiber-reinforced resin layer 36 from both the inner and outer peripheries, and the deformation of the rotating sleeve 17 into an hourglass shape is suppressed to a small extent.

By suppressing deformation, the thickness of the air bearing chamber 18 in the axial direction of the rotating sleeve 17 is maintained uniform, and an appropriate load force of the air bearing is ensured. In addition, local contact between both ends of the rotating sleeve 17 and the inner circumferential surface of the center housing 1 or strong contact with the sliding member 34, which may occur when the rotating sleeve 17 is deformed into an hourglass shape, is avoided, and severe wear of the rotating sleeve 17 is avoided. Prevented.

Furthermore, although the rotating sleeve 17 as a whole becomes hotter than the center housing 1 due to the high-temperature gas inside, thermal deformation is suppressed by the layers 36 of fiber-reinforced metal or fiber-reinforced resin from the inner and outer peripheries.
Thermal expansion of the rotating sleeve 17 as a whole is suppressed to a small level. As a result, changes in the thickness of the air bearing chamber 18 due to thermal expansion between the center housing 1 and the rotating sleeve 17 are suppressed, an appropriate amount of clearance is secured, and a good load force of the air bearing is maintained.

Furthermore, since the outer peripheral surface of the rotating sleeve 17 is made of highly wear-resistant fiber-reinforced metal or fiber-reinforced resin, even if the rotating sleeve 17 comes into contact with the center housing 1, wear is suppressed and durability is improved. do.

Next, FIG. 5 shows a rotary sleeve of a rotary compressor according to a second embodiment of the present invention. In this embodiment, a layer 36 of fiber-reinforced metal or fiber-reinforced resin is used.
are provided not only on the layers 36a and 36b on the inner circumferential surface and outer circumferential surface of the rotating sleeve 17, but also on both ends. The fiber-reinforced metal or fiber-reinforced resin layer 36c at both ends more reliably suppresses thermal deformation at both ends of the rotating sleeve 1.
The drum-shaped thermal deformation of the rotary sleeve 17 is further suppressed, and the clearance constituting the air bearing chamber 18 is maintained uniformly, thereby making the load force uniform, and local contact between both ends of the rotating sleeve 17 is suppressed. Wear is suppressed. Furthermore, the rotating sleeve 17 is provided with fiber reinforced metal or fiber reinforced resin layers 36c at both ends.
The wear resistance at both ends is improved, and even if the rotating sleeve 17 contacts the sliding member 34, wear is suppressed and durability is improved. Other configurations and operations are similar to those of the first embodiment.

[Effects of the Invention] As explained above, according to the rotary compressor of the present invention, fiber-reinforced metal or fiber-reinforced resin having a coefficient of thermal expansion smaller than that of the base material of the rotary sleeve is formed on the inner and outer peripheral surfaces of the rotary sleeve. By providing a layer, it is possible to suppress the hourglass-shaped deformation of the rotating sleeve and the thermal expansion of the entire rotating sleeve, and also to improve the wear resistance of the outer circumferential surface of the rotating sleeve, ensuring uniform and appropriate loading force of the air bearing. In addition, contact between the rotating sleeve and the inner circumferential surface of the center housing is minimized to ensure smooth rotation, and furthermore, it is possible to prevent wear of the rotating sleeve and improve durability. can get.

In addition, if a layer of fiber-reinforced metal or fiber-reinforced resin is provided on both ends of the rotary sleeve as well as on the inner and outer peripheral surfaces, it is possible to more reliably suppress the drum-shaped thermal deformation of the rotary sleeve, resulting in wear and tear at both ends of the rotary sleeve. It is possible to prevent this and obtain smooth rotation of the rotating sleeve.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a rotary compressor according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of the device shown in FIG. 1 taken along the - line, and FIG. 3 is a rotation of the device shown in FIG. FIG. 4 is a longitudinal sectional view of the device shown in FIG. 3, and FIG. 5 is a longitudinal sectional view of the rotary sleeve of a rotary compressor according to a second embodiment of the present invention. 1... Center housing, 2... Rotor, 6...
...Front side housing, 7...Rear side housing, 13...Axis of center housing,
14... Rotor axis, 15... Vane groove, 16
... Vane, 17 ... Rotating sleeve, 18 ... Air bearing chamber, 19 ... Inlet, 20 ... Outlet, 2
2... Suction chamber, 24... Suction side working chamber, 27...
Discharge chamber, 30... Discharge side working chamber, 35... Base material of rotating sleeve, 36, 36a, 36b, 36c...
...Fiber-reinforced metal or fiber-reinforced resin layer, A...rotation direction, t...thickness of fiber-reinforced metal or fiber-reinforced resin layer.

Claims (1)

[Scope of Claims] 1. A rotary sleeve is rotatably supported in a center housing via an air bearing chamber, and a rotor is rotatably housed inside the rotary sleeve eccentrically from the central axis of the rotary sleeve. In a rotary compressor configured by inserting vanes into and out of the rotor,
A rotary compressor characterized in that a layer of fiber-reinforced metal or fiber-reinforced resin having a coefficient of thermal expansion smaller than that of a base material of the rotary sleeve is provided on the inner peripheral surface and outer peripheral surface of the rotary sleeve. 2. The rotary compressor according to claim 1, wherein a layer of the fiber-reinforced metal or fiber-reinforced resin is provided on both ends of the rotary sleeve as well as on the inner and outer peripheral surfaces thereof.