WO2005052373A2 - Rotary compressor - Google Patents

Abstract

The invention is related to rotary machines, which can be used, for instance, as air compressors. The goal of this invention is to build up efficiency of machine as an air compressor at 5 high-speed rotation. The set task is resolved due to a revolving bushing installed on bearings inside housing, an intake port is made tangential toward bushing rotation direction, and a bushing has longitudinal ports. There are some other features making this invention distinguished from a prototype. Higher efficiency due to lower friction of revolving bushing and because of ability to use dynamics of incoming air streams is a definite advantage of the claimed invention.

Description

ROTARY COMPRESSOR

SUMMARY OF THE INVENTION

This invention relates to rotary machines that can be used, for example as compressors. The know i plate type rotary machines [1] include a stator with cylindrical boring, end walls, and canals for liquid supply and removal; eccentrically installed rotor has radial slots, within which plates have ability to reciprocate, outward edge of plate slides among the stator boring and press oneself to it because of either centrifugal force or springs or excessive pressure of liquid. Essential comparative speeds of sliding of plate outward and side edges along cylindrical boring and end walls of a stator is a main disadvantage of the known solutions. This leads to great losses on friction of plates, installed in radial slots, and their fast deterioration. This feature does not support an idea to use such machines as compressors. To get rid of this disadvantage it is attempted to install different kinds of bearings at outward end of plate [2]. Such kinds of bearings make rotor design more complicated. Rotary compressor with revolving bushing [3], consisting of middle frame, and side frames with intake and outlet ports is taken as a prototype. Revolving rotor is eccentrically installed inside the freely revolving bushing of a middle frame. The rotor has sliding gates. When the rotor turns, sliding gates' rotate the bushing. Distinguished feature of the prototype is that part of highly compressed air is supplied to the bushing throughout housing canals to provide freedom and easiness for the bushing rotation. These improvements let reduce speed of plates sliding along the case boring, decrease friction and increase efficiency correspondingly. However, the main disadvantage of greater friction of sliding between the bushing and the case boring remains. Reduction of this disadvantage at the expense of compressed air supply to a bushing does not resolve the problem efficiently because a bushing is not balanced and it takes effect from different forces, therefore an air cushion does not work efficiently. Besides, when this machine is used as a compressor for air supercharging at higher revolution speeds of a rotor, performance of intake and outlet ports at the compressor ends does not allow efficiently benefit from air flow dynamics, especially for large axle shape of housings. The goal of this invention is to increase efficiency of the machine when it operates as an air-supercharging device at higher rotation speeds. Solution for this problem is that the known rotary compressor, comprising of a housing with intake and outlet ports, inside the compressor housing a freely rotating » bushing is installed, on which a revolving rotor with sliding gates installed eccentrically; according to the invention a rotating bushing is mounted inside a housing on bearings, an intake port on a housing is made tangential toward bushing rotation direction, and a bushing has longitudinal ports. Another piece of the solution for this problem is to make the bushing ports dilative toward the intake port on a housing. The set problem is also resolved at the expense of that the ports on the bushing are made in such a way that their set makes a spiral shape. The set problem is also resolved because of the special lay out of the spiral grooves, which are made on outer surface of the bushing between ports for entanglement compression. The set problem is also resolved due to oil cases on the housing and bearing cavities are connected by canals to let oil flow from side to side. Installment of the revolving bushing on bearings allows to reduce load on outer surfaces of the bushing, to prevent from unequal load of sliding gates, and to keep the gap between bushing and housing the same at any direction. In addition, making an intake port on a housing tangential toward direction of the bushing rotation allows usage of kinetic energy of the air stream to increase compressor operation efficiency. This results from the fact that at high air-consumption air gets a high-speed stream, and if this stream rests on the end wall and then changes its motion direction along circle around compressor's axle it means waste of the air stream kinetic energy. In order to keep an intake port on circumference of the housing, it is required that ports on a revolving bushing should be done longitudinal. It is more efficient when ports on a revolving bushing arranged along spiral. In this case, sliding gates operate smoothly. Besides, such a design arrangement of ports on a bushing increases their open flow area. Making spiral grooves for entanglement compression on outer bushing surface contacting with inner boring of a housing increases efficiency of compressor operation because of elimination of air loss through the gap between a revolving bushing and the housing boring. BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a cross section of the rotary compressor. Fig. 2 is a longitudinal section of the rotary compressor. Fig. 3 shows dilative ports on the bushing. Fig. 4 shows bushing ports arranged along spiral. . Fig. 5 is a sectional view of Fig. 4 along line B-B, which in turn shows cross section of spiral grooves for entanglement compression. DESCRIPTION OF THE PREFERRED EMBODIMENT

Rotary compressor consists of housing lwith inner boring 2, inside which freely revolving bushing 4 is installed by means of bearings 3, Rotor 5 with sliding gates 6 is mounted eccentrically inside bushing '4. Intake ports 7 and outlet ports 8 take place on housing l .Oil case 9 is made at the bottom part of housing 1. Revolving bushing 4 is provided with holes 10 for airflow. Oil case 9 is connected to bearing cavities by means of canals 11. Grooves 12 for entanglement compression are made on surface of bushing 4. Bearing cavities are provided with sealing made in accordance with known technique (are not shown). Operation of the rotary compressor is as follows. At compulsory revolution of rotor 5, sliding gates 6 under response to centrifugal force press themselves to inner surface of bushing 4. Bushing 4 is mounted in such a way that it can rotate toward both housing 1 and rotor 5. That is why sliding gates 6 carry bushing 4. Under such conditions eccentrically mounted rotor 5 and traveling of sliding gates 6 inside housing force air to supercharge into outlet hole 8. Air inflows through intake port 7. Air stream becomes essential at high-speed revolution, and that is why the compressor intake port has to be tangential toward the bushing rotation. If this is a case, the compressor uses air dynamic pressure additionally and the compressor efficiency increases evidently. For the very same reasons as well as for smoother performance of sliding gates 6, ports 10 are made dilative and they set a spiral on bushing 4 along its outer surface. This way of making ports 10 provides ability for cavities between sliding gates to be continuously interchanging with intake 7 and outlet 8 ports. Grooves 12, also made on outer surface of bushing 4, start working as entanglement compression at high-speed rotation of bushing 4, therefore installment of bushing 4 on housing 1 with some clearance substantially reduces friction and increases compressor efficiency. The aggregate of distinguish features allows the compressor to increase its operation efficiency at higher air volume. All the works like designing, blueprints development, prototype building and testing have been completed and currently rotary compressors are to be implemented in a serial production. REFERENCES FOR EXAMINATION

1. T. M. Bashta - Hydraulic Machine Design. M.: Mashinostroyeniye, 1971. 205 pp, 95 drawings. 2. UK Application #2218469, F 01 C, 1991. 3. Japan Patent #3-6353 F 01 C, 1992.

Patent Attorney of Belarus.

Reg# 0020 E. A. Svidersky

Claims

1. The rotary compressor comprising of a housing with intake and outlet ports, a eely revolving bushing installed inside a housing, a revolving rotor with sliding gates is entrically installed on said bushing, which seats on bearings inside a housing, an intake Drt on a housing is made tangential toward bushing rotation direction, and a bushing has mgitudinal ports.

2. The rotary compressor of claim 1 wherein ports on a bushing are made dilative ward the intake port on a housing 3. The rotary compressor of claim 1 wherein the set of ports on a bushing has a spiral tape. 4. The rotary compressor of claim 1 wherein the spiral grooves between ports are ade on outer surface of a bushing for entanglement compression. 5. The rotary compressor of any claim 1 to 4 wherein a housing has an oil casing and :aring cavities are connected by canals to let oil flow through.

itent Attorney of Belarus ϊg# 0020 E. A. Svidersky