CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. provisional application number 62/592,456 filed on November 30, 2017 which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[0002] The invention relates to vehicles and engines having superchargers having electromagnetic clutch mechanisms.

BACKGROUND OF THE INVENTION

[0003] It is generally known that a supercharger may be utilized to increase the air pressure in the intake manifold of an internal combustion engine to provide an engine having a greater horsepower output capability. A conventional supercharger is generally mechanically driven by the engine, and is a drain on the engine when boosted air may not be required. As a result, a coupling mechanism such as a clutch may be disposed between the supercharger input and the rotors of the supercharger to selectively drive the supercharger.

[0004] There are various clutch configurations such as: a large pulley configuration; a small pulley configuration; and a remote mount clutch configuration. Each of these types of clutch assemblies may have potential disadvantages. A large pulley may be integrated to the rotor such that the pulley design is dependent on the torque capacity of the clutch. This results in undesirable packaging requirements because the required pulley diameters are typically too large. A small pulley configuration may be integrated with the clutch armature. In such a configuration, the clutch armature is generally rotating at the speed of the pulley even when the clutch is disengaged which is not desirable. For a remote-mount pulley configuration, the pulley has a large inertia associated with putting the clutch in an engaged position which is also problematic.

[0005] To overcome the above-described disadvantages a clutch may be integrated into the supercharger to allow the design of the pulley to be independent of the torque capacity of the clutch by separating the pulley from the clutch rotor and the clutch coil. The design of the clutch assembly may also allow the relatively large size of the clutch assembly to be closer to the main housing of the supercharger decreasing the packaging envelope in the area around the pulley.

[0006] In such a design, the supercharger may include an electromagnetic clutch to engage and disengage a driving force to the supercharger. In one aspect, the electromagnetic clutch may generate heat in its coil which may increase the resistance of the coil and lower a current flowing in the coil. This may reduce a clamping force of the clutch. There is a need in the art for an improved clutch and supercharger design that may reduce the potential negative effects of heat in a clutch coil.

SUMMARY OF THE INVENTION

[0007] In one aspect there is disclosed, a supercharger system for an engine having a supercharger including a housing and a pump moving coolant. A clutch assembly is integrated with the supercharger and disposed within the housing. The clutch assembly includes a clutch coil magnetically coupling and uncoupling the clutch assembly. The housing includes a cooling passage formed thereon. The cooling passage is positioned on the housing proximate the clutch coil. The cooling passage has coolant flowing therein wherein heat generated in the clutch coil is locally removed from the clutch coil through the housing and transferred to the flowing coolant.

[0008] In another aspect there is disclosed, a supercharger system for an engine having a supercharger including a housing and a pump moving coolant. A rotor assembly including rotors is disposed in the housing. A clutch assembly is integrated with the supercharger and disposed within the housing. The clutch assembly includes a drive shaft and a pulley connected to the drive shaft. A clutch rotor is connected to the drive shaft and a clutch armature is coupled to the rotors. A clutch coil is spaced along the drive shaft from the pulley and magnetically couples and uncouples the rotor and armature. An intercooler is provided. The housing includes a cooling passage formed thereon. The cooling passage is positioned on the housing proximate the clutch coil. The cooling passage has coolant flowing therein and the intercooler has coolant flowing therein wherein heat generated in the clutch coil is removed from the clutch coil through the housing and transferred to the flowing coolant.

[0009] In a further aspect, there is disclosed, a supercharger system for an engine having a supercharger including a housing and a pump moving coolant. A rotor assembly including rotors is disposed in the housing. A clutch assembly is integrated with the supercharger and disposed within the housing. The clutch assembly includes a drive shaft and a pulley connected to the drive shaft. A clutch rotor is connected to the drive shaft and a clutch armature is coupled to the rotors. A clutch coil is spaced along the drive shaft from the pulley and magnetically couples and uncouples the rotor and armature. The housing includes a cooling passage formed thereon. The cooling passage is positioned on the housing proximate the clutch coil. The cooling passage has coolant flowing therein wherein heat generated in the clutch coil is removed from the clutch coil through the housing and transferred to the flowing coolant.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a schematic representation of a vehicle propulsion system including an engine, supercharger, intercooler, radiator and pump;

[0011] Figure 2 is a perspective view of a supercharger having a cooling mechanism for a clutch;

[0012] Figure 3 is a sectional view of a supercharger having a cooling mechanism for a clutch;

[0013] Figure 4 is an end view of a supercharger having a cooling mechanism for a clutch;

[0014] Figure 5 is a side view of a supercharger having a cooling mechanism for a clutch;

[0015] Figure 6 is a schematic representation of a vehicle propulsion system including an engine, supercharger, intercooler, radiator and pump with a coolant flow path;

[0016] Figure 7 is a schematic representation of a vehicle propulsion system including an engine, supercharger, intercooler, radiator and pump with a coolant flow path;

[0017] Figure 8 is a schematic representation of a vehicle propulsion system including an engine, supercharger, radiator and pump with a coolant flow path;

[0018] Figure 9 is a schematic representation of a vehicle propulsion system including an engine, supercharger, radiator and pump with a coolant flow path;

[0019] Figure 10 is a schematic representation of a vehicle propulsion system including an engine, supercharger, radiator and pump with a coolant flow path; [0020] Figure 1 1 is a schematic representation of an ECU and control system for a vehicle propulsion system including an engine, supercharger, intercooler, radiator and pump with a coolant flow path.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Referring to the Figure 1 there is shown a schematic representation of a vehicle propulsion system that includes a supercharger 20 that is coupled to an engine 24 through an intercooler 22. The supercharger 20 provides a charge of air to the engine 24 to assist the combustion process.

[0022] The supercharger 20 may cool the charge of air using the intercooler 22 before routing to the intake manifold 28 of engine 24. The intercooler 22 may utilize a liquid coolant moved by a pump 30 to dissipate heat through radiator 32.

[0023] The supercharger 20 may include an electromagnetic clutch 34 to engage and disengage a driving force to the supercharger 20. In one aspect, the electromagnetic clutch 34 may generate heat in its coil 36 which may increase the resistance of the coil 36 and lower a current flowing in the coil 36. This reduction in current may reduce a clamping force of the clutch 34. There is a need in the art for an improved clutch and supercharger design that may reduce the potential negative effects of heat in a clutch coil 36.

[0024] In the depicted figures 1-5, the supercharger 20 may include a housing 38 having coolant passages 40 formed thereon that receives a liquid coolant from the pump 30 to dissipate heat from the supercharger 20, as will be described in more detail below. The pump 30 may be any type of pump capable of moving the liquid coolant. The pump also need not be associated with the intercooler 22. For example, the pump may be any pump associated with the vehicle such as a pump associated with a radiator or other cooling system of the vehicle.

[0025] Referring to Figures 2-5, the supercharger 20 may include the housing 38 that is separated into three joined sections. The joined sections may include a drive shaft housing 42 which receives a drive shaft 44, a clutch housing 46 which receives the electromagnetic clutch 34 and a rotor housing 48 which receives rotors 50. The housing 38 may be formed of various heat transmitting materials such as aluminum which acts as a good conductor of heat. In one aspect, the drive shaft housing 42 or the clutch housing 46 may include the cooling passages 40 formed therein. In one aspect, the cooling passages 40 are not included on the rotor housing 48 as temperature variation in the rotor housing 48 may present a problem with interaction of the rotors 50 which are spaced at very tight tolerances.

[0026] The cooling passages 40 may be in the form of a tube that is cast on to the housing 38. Alternatively, the cooling passages or tube 40 may be attached to the housing 38 such that it is in heat transmitting contact with the housing 38. In the depicted embodiment, the cooling passages 40 are formed on a portion of the drive shaft housing 42 proximate the coil 36 to remove heat from an area of the coil 36 and reduce potential resistance gains as described above. The localized heat removal of the cooling passages 40 and liquid coolant proximate the coil 36 prevents migration of heat to the rotors 50. The cooling passages may be formed within 10-15 mm of the coil to locally remove heat from the coil 36 without directly affecting the temperature of the rotors 50 but still prevent migration of heat from the coils 36 to the rotors 50.

[0027] In another aspect, the cooling passages 40 allow the clutch 34 to be sized smaller in comparison to prior art designs, as such prior designs are oversized relative to the loads being applied to avoid potential slipping of the clutch. Removal of the heat from the clutch coil 36 may allow for a smaller clutch to be utilized in a supercharger and reduce a packaging space of the supercharger. A smaller packaging is desirable as space in an engine compartment for modern vehicles is often very tight with many different systems requiring various amounts of space.

[0028] Referring to Figure 3, the clutch or clutch assembly 34 is disposed in the clutch housing 44. The clutch 34 includes a coil 36 that provides a magnetic force generated by electrical current running through the coil 36. The clutch 34 includes a clutch rotor 52 and a clutch armature 54. The clutch rotor 52 may be configured to be magnetized and set up a magnetic loop that attracts the clutch armature 54. The clutch rotor 52 may be connected to drive shaft 44 and/or pulley 56 which may be coupled to a crankshaft of a vehicle. The pulley 56 transmits torque from the crankshaft (not shown) to drive shaft 44 and to the rotors 50 when the clutch 34 is engaged. The clutch selectively links the drive shaft 44 to the rotors 50.

[0029] Referring to Figure 1 1, in use, the supercharger 20 may be regulated through the use of an electronic control unit ECU 58. The ECU 58 may include input and output signals 60 generated from various sensors 62 or control readings from the vehicle. The ECU 58 may include a microprocessor having sufficient memory to store a computer program for controlling the operation of the supercharger 20 including the clutch 34, the flow rate of the coolant from the pump to the passages 40 and the intercooler 22, the flow rate of air in the supercharger to the engine as well as other operating parameters.

[0030] Referring to Figure 1, the supercharger 20 receives air from a source and compresses the air to form an air charge that is routed to the intercooler 22 to cool the air charge before supplying the air charge to the intake manifold 28. The intercooler 22 uses a liquid coolant 64 moved by a pump 30 to dissipate heat through the radiator 32. The liquid coolant 64 is also supplied to the cooling passages 40 formed in the supercharger housing 38. The passages 40 may include appropriate fittings 66. The liquid coolant 64 enters at one end of the cooling passage 40 and removes heat through the housing 38 in an area proximate the coils 36. The heated coolant exits the passage 40 and is routed to the radiator 32. Dissipation of heat from the clutch 34 prevents increased resistance of the coil 36 and prevents potential slippage of the clutch 34. In one aspect, the heat generated by the coil may be in the range of from 40 to 200 degrees C. For such a heat generated, the flow of coolant through the passages may be regulated such that a flow of from 0 to 2 kg/hr may remove the desired amount of heat to prevent increased resistance as described above.

[0031] Referring to Figures 6-10 there are shown alternative flow paths for the coolant as described above with respect to Figure 1.

[0032] In Figure 6, the coolant flows from the radiator 32 to the pump 30 to the passages 40 in the supercharger 20 then to the intercooler 22 and back to the radiator 32.

[0033] In Figure 7, the coolant flows from the radiator 32 to the pump 30 to the intercooler 22 then to the passages 40 in the supercharger 20 and back to the radiator 32.

[0034] In Figure 8, the coolant flows from the radiator 32 to the pump 30 through the engine 24 then to the passages 40 in the supercharger 20 and back to the radiator 32.

[0035] In Figure 9, the coolant flows from the radiator 32 to the pump 30 to the passages 40 in the supercharger 20 through the engine 24 then and back to the radiator 32. [0036] In Figure 10, the coolant flows from the radiator 32 to the pump 30 to the passages 40 in the supercharger 20 and back to the radiator 32.

[0037] The various coolant routes may provide easy integration for various engine and vehicle types. In one aspect, the coolant flow may be integrated with the coolant flow in the intercooler to provide a source of coolant without adding additional pumps, although such a configuration may be utilized as shown in figures 8-10.

[0038] I claim: