Refrigeration – Automatic control – Responsive to vehicle body motion or traction
Reexamination Certificate
1999-08-04
2001-03-13
Tanner, Harry B. (Department: 3744)
Refrigeration
Automatic control
Responsive to vehicle body motion or traction
C062S243000, C310S095000, C192S084310
Reexamination Certificate
active
06199391
ABSTRACT:
BACKGROUND OF THE INVENTION
Vehicles such as automobiles have an air conditioner system for cooling a vehicle passenger. The air conditioner includes a compressor unit that is driven by the vehicle motor. The air conditioner drive for the compressor requires a substantial amount of power. There are instances where it is desired to limit the amount of power used to drive the air conditioner compressor, such as to conserve fuel or power. Where the vehicle is being powered by an electric motor, there is a particular need to conserve power being drained from the battery to run the air conditioner. This becomes more acute at higher motor speeds. In order to conserve power, it is desired to drive the air conditioner compressor at a relatively constant speed even though the vehicle's electric motor speed is being varied substantially, such as when accelerating the vehicle, traveling in heavy traffic, etc.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is an overall vehicle air conditioning system which allows better and tighter modulation control of the amount of torque transferred to the air conditioner compressor. This is achieved by the use of a magnetic clutch that receives driving input from the vehicle motor and the current or power to magnetic clutch is varied as the motor speed varies to modulate the torque supplied to the air conditioner. Preferably, the motor speed is sensed, and this and/or other sensed inputs are sent to controller which modulates the voltage quickly and incrementally to the magnetic clutch to modulate the magnetic flux field to keep it relatively constant and thereby keep the torque output from the magnetic clutch at a relatively constant value. The preferred magnetic clutch is unlike many clutches that are either fully engaged or fully disengaged in that it can be partially engaged as well as fully engaged or disengaged. The magnetic field can be modulated, i.e., have a controlled slip to transfer only a percentage of the torque, in order to provide a relatively constant output torque even though the electric motor speed is increasing substantially as is the speed of the input member of the magnetic clutch which is usually directly driven by the electric motor through a belt or gear drive.
In accordance with an important aspect of the invention, at high current, there is substantial slippage with the clutch driving element being rotated much faster than the clutch driven element which is connected to the air conditioner compressor. The magnetic clutch has a magnetic field between the electromagnets and the pole pieces and the magnetic field is kept relatively constant by electronic control to prevent higher current being inputted to the electromagnets when the motor speed increases.
In accordance with a further aspect of the invention, an electrical generator for supplying power to the magnetic clutch is incorporated into the magnetic clutch to supply electrical current to the electromagnets in the magnetic clutch. The electrical current from the electrical generator is modulated in a controlled manner by a computer controlled circuit for supplying electrical current to the magnetic clutch. Preferably, both the generator and the magnetic clutch are directly mounted on the A.C. compressor shaft and have a common rotatable input member driven by the vehicle electric motor. The use of a generator permits a non-contact application of power to the rotating pulley portion of the magnetic clutch, thereby avoiding the use of slip rings, brushes, or the like. Further, a rectifier rectifies the AC current generated into DC current for the electromagnetic clutch and a pulsing circuit is used to pulse the electromagnets of the clutch.
REFERENCES:
patent: 1548016 (1925-07-01), La Riboisiere
patent: 3552351 (1971-01-01), Willem et al.
patent: 3603105 (1971-09-01), Figa
patent: 3751181 (1973-08-01), Hayashi
patent: 3826937 (1974-07-01), Davies
patent: 3883633 (1975-05-01), Kohler
patent: 3924585 (1975-12-01), Woods
patent: 3932068 (1976-01-01), Zimmerman
patent: 4095922 (1978-06-01), Farr
patent: 4119184 (1978-10-01), Mower et al.
patent: 4152099 (1979-05-01), Bingler
patent: 4176630 (1979-12-01), Elmer
patent: 4189654 (1980-02-01), Mourier
patent: 4509091 (1985-04-01), Booth
patent: 4554491 (1985-11-01), Plunkett
patent: 4651922 (1987-03-01), Noba
patent: 4671739 (1987-06-01), Read et al.
patent: 4760898 (1988-08-01), Nyquist
patent: 4896064 (1990-01-01), Taiani
patent: 5045739 (1991-09-01), Kuwahara
patent: 5053666 (1991-10-01), Kliman et al.
patent: 5273143 (1993-12-01), Voss et al.
patent: 5307644 (1994-05-01), Cummins et al.
patent: 5469947 (1995-11-01), Anzai et al.
patent: 5548173 (1996-08-01), Stephenson
patent: 5565723 (1996-10-01), Dastidar
patent: 5566745 (1996-10-01), Hill et al.
patent: 5598705 (1997-02-01), Uzkan
patent: 5687823 (1997-11-01), Nakagawa et al.
patent: 5724941 (1998-03-01), Suzuki et al.
patent: 5763969 (1998-06-01), Metheny et al.
patent: 5775115 (1998-07-01), Lutz et al.
patent: 5893272 (1999-04-01), Hanselmann et al.
patent: 5900203 (1999-05-01), Needham et al.
patent: 0 730 337 (1996-09-01), None
patent: 0 899 858 (1999-03-01), None
patent: 2 278 242 (1994-11-01), None
patent: WO 93/24986 (1993-12-01), None
Foresman John Scott
Link Larry Ray
American Cooling Systems, LLC
Fitch Even Tabin & Flannery
Tanner Harry B.
LandOfFree
Magnetic clutch method and apparatus for driving a vehicle... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnetic clutch method and apparatus for driving a vehicle..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic clutch method and apparatus for driving a vehicle... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2455392