Mountable Printable Placard With Headband
A resilient headband in a shape for being mounted on the head of the user. The headband is equipped with a longitudinal slotted member for holding a placard.
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AbstractA microprocessor based control system generates optimal field and armature currents for a separately excited DC motor. The current levels for the field and armature coils are set by feedback control. Armature and field current setpoints are established in accordance with tabulated values selected for providing a required torque and speed in an optimal fashion. A table of corresponding values of armature voltage is also maintained. If the actual armature voltage is below the calculated value, then the field current setpoint is boosted by an amount sufficient to optimize output torque.Other References
| InventorsApplicationNo. 889227 filed on 07/08/1997US Classes:388/801, Field control, or field and armature control, by digital or combined analog and digital circuitry318/432, CONSTANT MOTOR CURRENT, LOAD AND/OR TORQUE CONTROL388/907.5Computer or microprocessorField of Search388/801, Field control, or field and armature control, by digital or combined analog and digital circuitry388/907.2, Bridge circuit388/907.5, Computer or microprocessor318/244, ALTERNATING CURRENT COMMUTATING MOTORS318/245, Universal or A.C.-D.C. motors318/432, CONSTANT MOTOR CURRENT, LOAD AND/OR TORQUE CONTROL318/433Control of motor load or device drivenExaminersPrimary: Ro, BentsuAttorney, Agent or FirmUS Patent References4079301, D.C. motor controlIssued on: 03/14/1978 Inventor: Johnson, III4408147, Method and apparatus for high efficiency operation of electromechanical energy conversion devices Issued on: 10/04/1983 Inventor: Gabel4422022, Speed control for truck Issued on: 12/20/1983 Inventor: Hill , et al.4520299, Turning speed controller for electric vehicles having dual drive motors Issued on: 05/28/1985 Inventor: Konrad5039924, Traction motor optimizing system for forklift vehicles Issued on: 08/13/1991 Inventor: Avitan5070283, Traction motor controller for forklift vehicles Issued on: 12/03/1991 Inventor: Avitan5264763, Optimizing system for vehicle traction motors Issued on: 11/23/1993 Inventor: Avitan5349279, Speed-dependent traction motor controller for vehicles Issued on: 09/20/1994 Inventor: Avitan5453672, Regulation system for decoupled efficiency optimized operation of DC traction motors Issued on: 09/26/1995 Inventor: Avitan5585706, Speed regulation of DC motor using current sensing means Issued on: 12/17/1996 Inventor: Avitan5642023Method and apparatus for the electronic control of electric motor driven golf car Issued on: 06/24/1997 Inventor: Journey Foreign Patent References
International ClassH02P 005/178 |