Title:
Rotary Vane Compressor with multiple Vanes having multiple line contact and rolling tip for ail automotive air-conditioning applications
Field of Invention:
This invention relates to the design method and system of an innovative Rotary Vane Compressor with which have the innovative features of using roller at the tip of the Vane to avoid rubbing with Stator bore by providing the pure rolling motion and having wavy profile on the sides of the Vane to replace the surface contact by line contact to reduce the sliding friction with the slot surface of Rotor and the pockets formed between the Vane and Slot are retaining and ensuring the lubrication for the Vanes , applicable for the cooling capacity range from 0.5 kW to 50 kW which can be used for all Air Conditioning applications like Car air-conditioning, Bus air-conditioning, Rail coaches Air-Conditioning and truck refrigeration units for transport of refrigerated goods.
Background of the invention: General Scenario:
Compressors are used for sucking the low pressure super heated (any type of refrigerants, HFC (Hydrofluoro Carbon) , HFO (hydrofluoro-olefin), NH3, C02 and etc..) refrigerant gas from Evaporator (through Internal Heat Exchanger (IHX) if it is connected in the circuit), compressing to high pressure and discharging the compressed refrigerant gas at high temperature to Condenser for de-superheating, Condensing and sub-cooling the refrigerant medium in the vapour compression Refrigeration systems used in the chemical industry, Process industry, Air Conditioning applications, Power generation units and many other applications. Though our disclosed invention put forward by the current patent application may find a number of other embodiments, we are presenting the invention through an embodiment especially applicable to the automotive Air Conditioning systems having Rotary Vane
Compressor which have the innovative features of using multiple Vanes having multiple line contact and rolling tip for the applications like Car air-conditioning, Bus air-conditioning, Rail coaches Air-Conditioning and truck refrigeration units for transport of refrigerated goods.
Automotive sector has been growing at a fast pace and due to tighter environment norms and steep competition the quest for efficiency increment, compactness, light weight and lower cost, higher productivity and lower lead times are increasing day by day.
Refrigerant Vapor Compression Refrigeration circuit:
The prime goal of the designers of automotive air conditioning systems is to design the compressor to deliver highest cooling capacity by consuming lowest power, which in turn will have the highest COP. The Power consumption of the compressor is the sum of adiabatic power and the frictional power by all moving parts. Hence, the designer must focus to design the compressor and its parts in such a way that the frictional power loss are at its lowest possible limit. A general thought process is to convert all possible surface contacts by line contacts and ensuring the lubrication at contacts at all point of operation, which leads to reduced frictional heat generation, longer operating life of lubricating oil and hence the parts of the compressor.
Problem Statement:
There exists a need of a high efficient compressor which must be compact, light weight and low cost to provide higher COP for the rated cooling capacity. The present invention addresses such a need. More particularly, the invention relates to devices and methods employing Rotary Vane Compressor with multiple Vanes which has the innovative features of having multiple Vanes with multiple line contact and rolling tip, leads to reduced frictional heat generation, longer operating life of lubricating oil and hence the parts of the compressor.
Prior Art:
The U.S. Patent no. 4,396,365 dated Aug 2, 1983 by Hayashi et al. disclosed the invention related rotary vane type compressor having a rotor mounted with a number of vanes each accommodated in a vane groove of a liner made of anti-abrasive material and a boss for fixing the liners and the liners are fixed in position with respect to the boss by integrally casting the liners and the boss by placing them in the predetermined position using light weight alloy, but the Vanes having plain surfaces on both sides of the Vanes and having surface contact with Rotor slot and rubbing action with stator bore.
The U.S. Patent no. 4,415,320 dated Nov 15, 1983 by Maruyama et al. disclosed the invention related to rotary compressor of the sliding vane type suitable for use as the compressor of a refrigerator incorporated in an air conditioning system for vehicles, which consists of Sliding Vanes, having plain surfaces on both sides of the Vanes and having surface contact with Rotor slot and rubbing action with stator bore.
European Patent Application no. EP0264005A2 dated 23 Sep 1987 by Nakajima et al. disclosed the invention related to a sliding-vane rotary compressor having substantially elliptical bore with dual compartment and multiple vanes are of plain side surfaces with tip is having rubbing action with the bore.
The U.S. Patent no. 4,911,624 dated Mar 27,1990 by Bagepalli disclosed the invention related to an arrangement reduces friction between the sliding vane and rolling piston of a rotary compressor, which consists of a single vane having rolling tip and oil groove for the lubrication of the tip roller, and the Vane is having plain surfaces on both sides of the Vane and having surface contact with Stator vane slot.
The U.S. Patent no. 5,302,096 dated Apr 12, 1994 by Cavalleri disclosed the invention related to rotary vane compressor includes two stator chambers allowing two compression strokes for each revolution of the rotor. The shape of the chamber walls is specifically designed through the use of a sine function to increase efficiency of breathing of the compressor by providing a larger initial starting volume which reduces to a smaller discharge volume, but Vanes are having plain
surfaces on both sides of the Vanes and having surface contact with Rotor slot and rubbing action with stator bore.
The U.S. Patent no. 8206140B2 dated Jun 26 2012 by Ooi et al. disclosed the invention related to an exemplary revolving vane compressor includes a cylinder having a discharge port in and through the cylinder. A rotor housed within the cylinder is eccentrically mounted relative to the cylinder. A vane is mounted in a slot in the rotor, but vane is having plain surfaces on both sides and having surface contact with Rotor slot.
(Table Removed)
Disadvantages of prior art:-
1. Vane is having surface contact with rotor slot
2. Vane is having rubbing action with stator bore
3. The above features contribute to more frictional heat generation
4. Also, the power consumption of the compressor is high, hence lower COP.
5. Due to high heat, the degradation of lubricating oil in short duration
6. Contributing to more global warming
SUMMARY OF THE INVENTION:
The Rotary Vane type Refrigeration compressor for Automotive and refrigeration applications is consists of rotor with multiple slots, multiple Vanes, Eccentric Stator with suction ports and Discharge Ports, in addition set of discharge reed valves.
The rotor is supported radially and axially to transmit the loads to stator.
The Vane having wavy profile on the sides to replace the surface contact by line contact to reduce the sliding friction with the slot surface of Rotor and the pockets formed between the Vane and Slot are retaining and ensuring the lubrication for the Vanes.
The multiple vanes inserted in to the rotor vane slots, have the rolling tip consists of cylindrical pocket and roller for the entire length of the rotor to avoid rubbing action with stator bore by providing the pure rolling motion, which in turn' will have only very negligible frictional heat generation, hence the life of the lubricating oil and the parts of rotary vane compressor is greatly improved.
According to the design of rotary vane compressor and the displacement and operating . requirements, the no. of vanes can vary from 2 to 20.
The above, described vane design is also applicable for the sliding single vane compressor or rolling piston compressor application.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of the preferred embodiments of the invention, reference will
now be made to the accompanying drawings in which:
Figure 1 of 12 : Prior art: U.S. Patent no. 4,396,365 dated Aug 2,1983 by Hayashi Figure 2 of 12 : Prior art: U.S. Patent no. 4,415,320 dated Nov 15,1983 by Maruyama et al. Figure 3 of 12 : Prior art : European Patent Application no. EP0264005A2 dated 23 Sep 1987 by Nakajima Figure 4 of 12 : Prior art: U.S. Patent no. 4,911,624 dated Mar 27,1990 by Bagepalli
Figure 5 of 12 : Prior art: U.S. Patent no. 5^02,096 dated Apr 12,1994 by Cavalleri Figure 6 of 12 : Prior art: U.S. Patent no. 8206140B2 dated Jun 26 2012 by Ooi Figure 7 of 12 - Rotary Vane compressor with multiple vanes having rolling tips Figure 8 of 12 - Rotary Vane compressor with multiple vanes having rolling tips and multiple line contacts on the'rotor vane slot.
Figure 9 of 12 - Detailed view of Vane showing rolling tips and multiple line contacts on
the rotor vane slot with multiple pockets for retaining lubricating oil.
Figure 10 of 12 - Enlarged view of Vane showing multiple line contacts on the rotor
vane slot with multiple pockets for retaining lubricating oil.
Figure 11 of 12 - Rotary Vane compressor with multiple vanes having rolling tips and
multiple line contacts on the rotor vane slot.
Figure 12 of 12 - Rotary Vane compressor with multiple line contacts on the rotor vane
slot.
DETAILED DESCRIPTION
1. According to one aspect of the invention, Rotary vane Compressor for air
conditioning and refrigeration applications in general and automotive application
in particular comprising of multiple Vanes, a Rotor with multiple vane slots,
eccentric housing with bore having suction and discharge ports, set of reed type
discharge valves, set of anti-friction roller or ball bearings to support the rotor,
the multiple vanes are having one or all of the innovative features of wavy profile
on the sides, Rolling tip with pocket for roller.
2. The multiple vanes inserted in to the rotor vane slots, have the rolling tip consists of cylindrical pocket and roller for the entire length of the rotor to avoid rubbing action with stator bore by providing the pure rolling motion, which in turn will have only very negligible frictional heat generation, hence the life of the lubricating oil and the parts of rotary vane compressor is greatly improved.
3. The rotor is supported radially and axially to transmit the loads to stator using anti-friction type roller or ball bearings as simply-supported construction.
4. Suction and discharge chambers are separated and sealed by using O-rings.
5. The main housing consists of bore for the stator which has O-ring grooves at the drive end and as well as at the non-drive end and the rotor with set of radial bearings with drive side and non-drive side covers to form the closed working chambers
6. In the case of the compressor is driven by the automotive main engine through the belt, and then the front head cover has the provision for the mounting of Electro-Magnetic clutch.

Claims
What is claimed is:
1. A Rotary vane Compressor for air conditioning and refrigeration applications in general and automotive application in particular comprising of multiple Vanes, a Rotor with multiple vane slots, eccentric housing with bore having suction and discharge ports, set of reed type discharge valves, set of anti¬friction roller or ball bearings to support the rotor, the multiple vanes are having one or all of the innovative features of wavy profile on the sides, Rolling tip with pocket for roller.
2. The Vane having wavy profile on the sides to replace the surface contact by line contact to reduce the sliding friction with the slot surface of Rotor and the pockets formed between the Vane and Slot are retaining the lubrication oil at all times and ensuring the lubrication for the Vanes.
3. The Vanes are having Cylindrical pocket throughout the length of the vane at the tip and cylindrical roller is inserted in to the pocket with the vane will retain the roller during the complete rotation of shaft, rolling tip is to avoid
rubbing action seen in the conventional vanes of rotary vane compressor and having pure rolling motion leads to reduced frictional heat generation, longer operating life of lubricating oil and hence the parts of the compressor.
4. The Vane having both wavy profile and rolling tip to enhance the mechanical efficiency, avoid the over heating of oil, improve the operating life of the rotary vanes and lubricating oil.
5. According to the design of rotary vane compressor and the displacement requirements, the no. of vanes can vary from 2 to 20.
6. The above described vane design is also applicable for the sliding single vane compressor or called it as rolling piston compressor.
7. Stator housing design is in such a way that it can have single or multiple working chambers, accordingly the set of reed type discharge valves are mounted at the discharge port locations.
8. The Composite construction of Vane is made up of partially using composite metallic materials (Aluminium, Cast-Iron, Steel) etc...(by forging, machining/ casting, molding)) and the rest with either of Non-metallic materials like PTFE, PEEK, PPS through injection molding process or entirely made up of Non-metallic materials like PTFE, PEEK , PPS through injection molding process by which the additional machining is completely avoided and made possible with 40% ~ 50% weight reduction and about 70% ~ 80% reduction in manufacturing time.
9. The non-metallic materials referred in the point no.5 includes the variants of PTFE, PEEK and PPS with 10% to 30% of Glass Filled and 10% to 30% of carbon Filled grades.
10. Optionally, Rotary vane compressor consists of inbuilt self driven oil pump of types, gear pump, Lobe type, Gerotor pump, Screw or Visco-pump mounted directly on to the non-drive end of the shaft, particularly it is of Gerotor type, sized to provide adequate lubricating oil quantity for the extreme operating conditions.
11. Optionally the Design is also having a variant that the lubrication is made to the vane contacts by the innovative feature of orifice holes drilled through the centre of the Rotor shaft and the cross connecting injection holes are
made in such a way that the injection is directly forced to the contact points inside the rotor vane slots.
12. As per one of this embodiment, the design of Rotary Vane compressor consists of Multiple Vanes having rolling tip and line contacts on the rotor slot surface is applicable for the applications where the drive is through the Electro-Magnetic Clutch, which is driven by the Automotive Engine through belt (type A, type B or Poly groove types).
13. As per one of this embodiment, the design of Rotary Vane compressor consists of Multiple Vanes having rolling tip and line contacts on the rotor slot surface is applicable for the applications where the drive is directly by an Electric Motor (of any suitable voltage supply) which is of open type, Semi-Hermetic and Fully Hermetic Design of Compressors.
14. As per this embodiment, application of Rotary Vane Compressor design as per this Invention, includes the automotive air-conditioning (Car and Bus Segments) and refrigeration (Reefer trucks etc... ) with refrigerant types like HFC (Hydro-Fluoro Carbon) , HFO (Hydro-Fluoro-olefin), NH3, C02 and etc.,) in general and specific to R134a, R404a, R407c, R410a , R1234yf, CO2,Refrigerants.