Title:
Swash plate type Refrigeration Compressor with Composite Housings for all automotive air-conditioning applications
Field of Invention:
This invention relates to the design method and system of a very efficient swash plate type piston Compressor which has the innovative features of housings and covers 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 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 the sucked super heated gas from low pressure to high pressure and discharging or delivering the compressed high pressure further super heated 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 swash plate type piston Compressors 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 and compactness and weight reduction is increasing day by day.
The prime goal of the designers of automotive air conditioning systems is to design the main components like Compressor, Condenser and Evaporator to achieve highest cooling capacity by lowest power consumption. Whereas the OEM's demands are increasing in terms of compact and light weight parts day by day due to the need of competing with overall efficiency of the vehicle in terms of fuel economy and emission levels as well. The efficiency of the system is directly related with efficiency of the parts in the system.
Problem Statement:
There exists a need of a high efficient compressor which can provide higher COP for the wider operating conditions with their rated cooling capacities at the same time the compressor has to be as compact as possible and as light weight as possible. The present invention addresses such a need. More particularly, the invention relates to devices and methods employing swash plate type piston Compressor which has the innovative features of housings and covers 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 for the cooling capacity ranges 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.
PAI PolyAmide Imide
PI Poly Imide
PF Phenol Resin
EP Epoxy Resin
PTFE PolyTetraFluoroEthylene
PEEK PolyEtherEtherKetone
PPS . PolyPhenylene Sulfide
Prior Art:
The U.S. Patent No. 5996467 dated 7 Dec 1999, issued to Churgay et al. disclosed that the swash plate in Swash plate type compressor is having coating of a thermoset composite material which is polymer (PTFE) based and includes 1-20 volume percent metal particles.
The U.S. Patent No. 6926779 dated 9 Aug 2005, issued to Bin disclosed that the swash plate in Swash plate type compressor is having coating of lead-free copper-based coating layer with Bismuth, Cobalt, PTFE, Graphite, MoS2.
The U.S. Patent application No. 20080304960 dated 11 Dec 2008, issued to Cvjeticanin et al. disclosed that the radial compressor of Turbocharger having plastic compressor housing comprises at least in some areas a plastic and/or a metal.
The U.S. Patent application No. 20110085900 dated 14 April 2011, issued to Schutz disclosed that the Housing segment of compressor of a gas turbine, in particular of an aircraft gas turbine is made of one of a metal, a metal alloy, a ceramic, a fiber-reinforced composite material and a combination of at least two of the aforesaid materials.

(Table Removed)
Disadvantages of prior art:-
1. Housings and covers are made up on entirely using Cast Iron, Steel, and
Aluminium Alloy by using one of the manufacturing processes of Casting, Forging,
Injection molding, by which they are higher in weight.
2. Housing and Covers need additional machining to improve the accuracy of
dimensions and surface finish as per the requirement.
3. The above features are responsible for higher weight of compressor and more
expensive in terms of cost and duration of manufacturing.
4. which together Contributing to more global warming
SUMMARY OF THE INVENTION:
In summary,
This invention relates to the design method and system of a very efficient swash plate type piston Compressor which has the innovative features of housings and covers 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 of compressors.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 of 5 - Schematic cross-section view of Swash plate type compressor
Figure 2 of 5 - Front view of Housing set (Front Cylinder Block & Rear Cylinder Block)
Figure 3 of 5 - Sectional view of Housing set (Front Cylinder Block & Rear Cylinder Block)
Figure 4 of 5 - Front view of Housing set (Front Cylinder Block & Rear Cylinder Block)
with cylinder liners
Figure 5 of 5 - Sectional view of Housing set (Front Cylinder Block & Rear Cylinder Block)
with cylinder liners
DETAILED DESCRIPTION
1. A Swash plate type compressor includes Front Head Cylinder, Rear Head Cylinder, Front Side Cover, Rear Side Cover, Shaft with Swash plate and multiple double ended pistons having the mating cylindrical bore in the housing at equal-angular distance between the pistons.
2. The double ended pistons are connected to Swash plate through Semi-Spherical Shoes on either side of the swash for transferring the compression load and providing the motion to the pistons.
3. The compression load acts on Piston is transferred to Swash plate through the pair of shoes.
4. Swash plate with 2 identical thrust bearing of kind anti-friction roller or ball bearings on opposite sides of Swash for transferring the bi-directional thrust loads to the housings.
5. The drive shaft is guided by either anti-friction type ball or roller bearings or bush bearings on both the sides of swash plate.
6. The bearings and shoes are lubricated either by splashing by swash plate or using oil pump (Gear pump or Gerotor pump).
7. The above features of compressor is shown in Figure 1 of 5.

Claims:
What is claimed is:
1. A swash plate type Compressor for air conditioning applications in general and automotive application in particular comprising of housings 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, set of suction and discharge valves, valve plate, Front Head Cover and Rear Head Cover either entirely made up of metallic materials (Aluminium, Cast-iron, Steel) etc...(by forging, machining, casting, molding) or Non-metallic materials like PTFE, PEEK , PPS through injection molding process, the Swash plate integral with the input drive shaft, set of thrust bearings either of anti-friction roller or ball bearing type and radial bearings either of anti-friction roller or ball bearing or bush bearing type for taking the axial and radial loads in addition to provide the axial and radial constraints to the input shaft with negligible friction, as shown in Figures 1 of 5 to Figure 5 of 5.
2. The Non-metallic material and its grades are selected based on the Compressive Strength, Shear Strength, flexural Rigidity, Linear thermal Expansion coefficients, Moldability, Machinability and High Temperature Resistivity.
3. The non-metallic materials referred in the point no.1 includes the variants of PTFE, PEEK and PPS with 10%, 20%, 30% of Glass Filled and 10%, 20%, 30% of carbon Filled grades.
4. As per the material grades listed in point no.2 , there is about 40% to 50% weight reduction compared to the housings and covers entirely made up on Aluminium Alloy.
5. Combination of composite material construction is as per the table 1 of 1,
but not limited to the combination given in the table 1 of 1.
6. The weight reduction explained in the point no.3 reduces the overall weight
of vehicle on which the compressor is mounted.
7. By the use of non-metallic material grades listed in point no.2, the operating
axial and radial clearances of double ended piston and cylinder bore are
lower, hence the volumetric efficiency is higher than the conventional
designs with Aluminium Alloy.
8. The cylinder bore are covered of the sizes ranges from 10 mm to 50mm in nominal Diameter.
9. The range of cylinder bore nominal diameters covered in the point no.6 as above, includes the specific Diameters namely 25, 28.5,29.5, 30.5, 32, 34, 36, 38,40 , 42, 46, 50mm to name a few.
10. In a preferred embodiment injection molding may be used as one of the
manufacturing methods.
11. The prime advantage of the hereby disclosed invention is the elimination of
machining process, secondary coatings or surface treatments which are
required in conventional compressors. Another inherent advantage of this
invention is to achieve a better anti-friction surface and thus resulting in less
wear and tear.
12. The combination of metallic materials and either of PTFE, PEEK, PPS materials together are taking care of the structural stiffness and rigidity of the parts of Compressor.