FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
COMPLETE SPECIFICATION (See section 10 and rule 13)
1. TITLE OF THE INVENTION:
Compressor for Air Conditioning System of Vehicle
2. APPLICANT;
(a) NAME: MAHINDRA & MAHINDRA LIMITED
(b) NATIONALITY: Indian Company registered under the
provisions of the Companies Act-1956.
(c) ADDRESS: R&D Center, Automotive Sector, 89,
M.I.D.C, Satpur, NASHIK - 422 007 Maharashtra State, India
3. PREAMBLE TO THE DESCRIPTION:
COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

Compressor for Air Conditioning System of Vehicle
Field of the invention
The present invention relates to an air conditioning system of a vehicle, and more particularly, relates to a dual power source compressor for the air conditioning system of vehicles.
Background of the invention
The function of an air conditioning system is to remove the heat and humidity from a passenger compartment of a vehicle. Generally, the air conditioning system (herein after 'the system') includes three main parts: an evaporator, a compressor and a condenser in which a compressed refrigerant is made to undergo a repeated process of vaporization (evaporation), liquefaction and re-vaporization to cool the passenger compartment. There are a few other parts to keep the system running smoothly.
Generally, the system operates as illustrated in figure 1. The compressor is connected to the condenser. The compressor compresses and pushes a refrigerant gas towards the condenser. The condenser is a radiator that serves to radiate heat from the hot, compressed gas and converts the gas into a high-pressure liquid form. The condenser is connected to the expansion valve that receives the liquid refrigerant from the condenser via a receiver-dryer that absorbs and removes moisture from the liquid refrigerant. The expansion valve reduces the pressure and temperature of the refrigerant and sends into the evaporator.

The evaporator is located in the passenger compartment and causes the low-pressure liquid to absorb heat from the passenger compartment and convert into a gas again that moves out of the evaporator. A fan blowing over the outside of the evaporator blows cool air into the passenger compartment. The gaseous refrigerant then enters the compressor where it is pressurized and the whole process starts all over again.
Conventionally, the compressor of the system is driven on a single power source that may be derived from a vehicle's engine or from an electric motor. Figures 2 and 3 show a prior art air conditioning system in which the compressor is directly connected to an engine shaft. The compressor includes a pulley and a clutch. The clutch moves in a single direction to engage/disengage the pulley with a belt of the engine shaft to transfer power from the engine shaft to the compressor.
However, the use of engine power to run the compressor, particularly in smaller vehicles with smaller engines, results in a significant and sudden increase in engine load thereby decreasing the performance of the engine. Moreover, when the engine is stopped to bring the vehicle in a stationary condition, the compressor stops operating preventing cooling of the air in the passenger compartment.
Due to the constraints resulting from the use of an engine driven compressor, it is often suggested that an electrically driven system would provide a much better solution. However, electrically driven compressors are not feasible on current vehicles due to insufficient electrical power and lack of high powered and efficient integrated starters/ generators.
Accordingly, there exists a need to provide a compressor for an air conditioning system of vehicles that overcomes the problem in the prior art.

Objects of the invention
An object of the present invention is to cool a passenger compartment of a vehicle even when an engine is OFF and the vehicle is in a stationary condition.
Another object of the present invention is to facilitate the air conditioning operation of the vehicle on a dual power source.
Yet another object of the present invention is to reduce thrust and compressor load on the engine thereby reducing fuel consumption and improving the engine performance.
Summary of the invention
Accordingly, the present invention provides a compressor for an air conditioning system of a vehicle. The air conditioning system includes a condenser, an expansion valve, an evaporator, a first battery armature, a second battery armature, a generator and a plurality of connecting means.
The compressor is positioned in a sealed compartment on an engine block of the vehicle. The compressor comprises a drive, a pulley and a clutch. The drive operates for compressing a refrigerant. The pulley is secured to the drive and adapted for removably engaging with any of a first power source and a second power source for operating the drive. The first power source is the engine shaft and the second power source is an electric motor. The electric motor runs on the second battery armature that is charged by the generator in the moving condition of the vehicle.

The clutch is secured to the pulley. The clutch is capable of moving/sliding towards any of the power sources for removably engaging the pulley with the first power source in a moving condition of the vehicle and with the second power source in a stationary condition of the vehicle. The clutch includes a plurality of spline gears and a plurality of magnets. The plurality of spline gears allows the clutch to move towards any of the power sources without losing grip with the pulley and engage the pulley with any of the power sources.. The plurality of magnets causes the clutch to shift to and from the power sources based on the moving and stationary conditions of the vehicle.
The engagement of the pulley with any of the first power source and the second power source causes the drive to operate and compress the refrigerant thereby resulting in cooling of a passenger compartment of the vehicle.
Brief description of the drawings
The objectives and advantages of the present invention will become apparent from the following description read in accordance with the accompanying drawings wherein,
Figure 1 shows a schematic view illustrating a prior art air conditioning system and an operation thereof;
Figure 2 shows another prior art air conditioning system having a compressor that runs on a single power source/engine power;
Figure 3 is a side view of the compressor of figure 2 showing a single clutch type compressor pulley, in accordance with the prior art;

Figure 4 shows an air conditioning system having a dual power source compressor, in accordance with the present invention;
Figures 5 and 6 show perspective views of the compressor of figure 4 attached to an electric motor;
Figures 7 and 8 are exploded views of the compressor showing attachment with the electric motor;
Figure 9 is a perspective view of the compressor showing a clutch and a pulley, in accordance with the present invention;
Figure 10 shows an exploded view of the compressor of figure 9;
Figure 11 shows a schematic view of the clutch of the compressor, in accordance with the present invention; and
Figure 12 shows an inter linkage between individual parts of the system to perform cooling operation using two different power sources on demand, in accordance with the present invention.
Detailed description of the invention
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with the prior art techniques and approaches are overcome by the present invention as described below in the preferred embodiment.

The present invention provides a compressor for an air conditioning system of a vehicle. The compressor operates on a dual power source to ensure continuous cooling of the vehicle even when an engine is OFF and the vehicle is not moving.
This present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.
Referring now to figure 4, an air conditioning system (100) (hereinafter "the system (100)") for a vehicle (not shown) in accordance with the present invention is shown. The system (100) comprises a condenser (10), an expansion valve (20), an evaporator (30), a first battery armature (40A), a second battery armature (40B), a generator (45), a compressor (50) and a plurality of conduits/ connecting means (60). In an embodiment, the system (100) uses any one of wired and wireless connecting means (60) for connecting the above mentioned components and for transferring electrical power and required signals there through.
Referring now to figures 5 to 12, the compressor (50) for the system (100) in accordance with the present invention is shown. The compressor (50) is positioned in a sealed compartment (not shown) on an engine block (110) of the vehicle as per requirement of the packaging and space availability. The compressor (50) comprises a drive (42), a pulley (44) and a clutch (46).
The drive (42) operates for compressing a refrigerant that passes into the condenser (10) and from the condenser (10) into the evaporator (30) via the expansion valve (20) to cool air in a passenger compartment (not shown) of the vehicle. The air cooling/ conditioning operation is well known and believed to be within the scope of the prior art, and therefore will not be discussed in detail herein.

The pulley (44) is secured to the drive (42) for operating the drive (42). The pulley (44) is adapted for removably engaging, by means of the clutch (46), with a dual power source selected from any of a first power source (115) and a second power source (120) based on a user selected operating condition of the vehicle. The user is a driver or an occupant(s). The operating condition of the vehicle includes a moving condition and a stationary condition.
The first power source (115) is an engine shaft positioned on the engine block (110) to provide mechanical power to the compressor (50) when the vehicle is in the moving condition and the engine is ON. The first power source (115) (herein after 'the engine shaft (115)') derives power from the first battery armature (40A) for engine cranking/starting. The first battery armature (40A), in the vehicle moving condition, is capable of reserving power for engine starting/cranking. The first battery armature (40A) is a vehicle's battery. The first battery armature (40A) is cut off from the system (100) to avoid being used by the compressor (50) when the vehicle is in the stationary condition and the engine is OFF.
The second power source (120) is an electric motor. In an embodiment, the electric motor is a DC motor. The second power source (120) (herein after 'the electric motor (120)') derives power from the second battery armature (40B) in the stationary condition of the vehicle. The second battery armature (40B) is a standby/additional battery installed in a boot space (not shown) or in an engine compartment (not shown) of the vehicle as per the availability of convenient space.
However, it is understood that when the second battery armature (40B) gets completely discharged in the stationary condition of the vehicle, the electric motor (120) derives some of the power reserved by the first battery armature (40A) to drive the compressor (50) depending on gas pressure in other alternative

embodiments of the system (100) per intended use. In such a condition, the running time of the electric motor (120) reduces based on the reserved power of the first armature battery (40A).
The second battery armature (40B) is in a parallel connection with the first battery armature (40A). In an embodiment, the battery armatures (40A and 40B) are 12V DC batteries. The battery armatures (40A, 40B) are charged at a same time by power supplied by the generator (45) in the moving condition of the vehicle. The generator (45) is an existing charging facility mounted on the vehicle.
The clutch (46) is secured to the pulley (44). Specifically, the clutch (44) is a dual clutch mechanism capable of moving/sliding on either side/direction towards the engine shaft (115) as well as towards the electric motor (120) in response to a signal indicative of the user selected operating condition of the vehicle. In an embodiment, the clutch (44) is moved manually or by an automated device (not shown) for example a programmable automated controller, upon receiving the signal from a manual switch (not shown) or a user defined equipment (not shown) for example a selector switch incorporated on a dashboard.
The clutch (46) includes a plurality of spline gears (45) and a plurality of magnets (not shown). The plurality of spline gears (45) allows the clutch (46) to move in either direction to engage the pulley (44) with any of the engine shaft (115) and the electric motor (120) without losing grip or linkage with the pulley (44). The plurality of magnets allow the clutch (46) to shift to and from the engine shaft (115) and the electric motor (120) based the signal received according to the moving and stationary condition of the vehicle and as and when required to shift the load. In the moving condition of the vehicle when the engine in ON, the clutch (46) moves towards the engine shaft (115) using the plurality of spline gears (45) to

engage the pulley (44) thereto thereby operating the drive (42) through a belt (not shown) of the engine shaft (115) with the engine power. In the stationary condition of the vehicle when the engine is OFF, the clutch (46) disengages the pulley (44) from the engine shaft (115) using the plurality of magnets and moves/shifts towards the electric motor (120) to engage the pulley (44) with the electric motor (120) thereby operating the drive (42) through the power delivered from the second battery armature (40B). Thus, the engagement of the pulley (44) with any of the engine shaft (115) and the electric motor (120) causes the drive (42) to operate and compress the refrigerant thereby resulting in cooling of the passenger compartment of the vehicle.
Advantages of the invention
1. When the vehicle stops, the compressor (50) runs on power supplied from the electric motor (120) without starting the engine to cool the passenger compartment.
2. The system (100) is upgraded to enable the compressor (50) to run with power from the second armature battery (40B) to the extent of battery capacity to start the engine when there is no power from the engine shaft (115).
3. The second battery armature (40B) runs the system (100) for at least 3 hours and gets charged only in 1.5 hours when the vehicle is running.
4. The system (100) does not require an external charging facility for the battery armatures (40A, 40B).
5. This type of power consumption allows the system (100) to utilize full capacity of the batteries (40A, 40B) and run for long time.
6. The electric motor (120) while running reduces the engine thrust and direct load on the engine by 50 % thereby improving the engine performance and thus reducing the fuel consumption by 5-7 %.

7. The compressor (50) is installed in the sealed compartment on the vehicle that eliminates the mechanical losses of power transmission associated with the prior art pulley and belt mechanism thereby improving the engine performance by 5-7%.
8. The prior art clutch acts in a single direction to engage and disengage the pulley. In the system (100), the clutch function is extended to work in the dual direction that is to move and engage in the directions of the electric motor (120) and the engine shaft (115) in response to the signal from the user defined equipment or manual switch signal.
9. The assembly of the engine shaft (115)/ electric motor (120), the pulley (44) and the clutch (46) is capable of being placed on any position as per packaging requirements of the system (100) and the vehicle.
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and. approaches are overcome by the present invention described in the present embodiment. Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or matter. The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention.

We claim:
1. A compressor (50) for an air conditioning system (100) of a vehicle, the air conditioning system (100) having a condenser (10), an expansion valve (20), an evaporator (30), a first battery armature (40A), a second battery armature (40B), a generator (45) and a plurality of connecting means (60), the compressor (50) comprising:
a drive (42) that operates for compressing a refrigerant;
a pulley (44) secured to the drive (42) and adapted for removably engaging with any of a first power source (115) and a second power source (120) for operating the drive (42); and
a clutch (46) secured to the pulley (44), characterized in that, the clutch (46) being capable of moving/sliding towards any of the power sources (115,120) for removably engaging the pulley (44) with the first power source (115) in a moving condition of the vehicle and with the second power source (120) in a stationary condition of the vehicle, wherein, the engagement of the pulley (44) with any of the first power source (115) and the second power source (120) causes the drive (42) to operate and compress the refrigerant thereby resulting in cooling of a passenger compartment of the vehicle.
2. The compressor (50) as claimed in claim 1 is positioned in a sealed compartment on an engine block (110) of the vehicle.
3. The compressor (50) as claimed in claim 1, wherein the first power source (115) is the engine shaft and the second power source (120) is an electric motor.

4. The compressor as claimed in claim 1, wherein the electric motor (120) runs on the second battery armature (40B).
5. The compressor as claimed in claim 1, wherein the battery armatures (40A, 40B) are charged by the generator (45) in the moving condition of the vehicle.
6. The compressor as claimed in claim 1, wherein the clutch (46) includes a plurality of spline gears (45) to move towards any of the power sources (115, 120) without losing grip with the pulley (44) and engage the pulley (44) with any of the power sources (115,120).
7. The compressor as claimed in claim 1, wherein the clutch (46) includes a plurality of magnets shifting to and from any of the power sources (115, 120) based on the moving and stationary conditions of the vehicle.