Patents by Inventor Raymond W. Throssell

Raymond W. Throssell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4283672
    Abstract: A stepper motor drive which sequentially energizes the windings of a stepper motor (1,2,3,4). The drive includes a binary counter (11) fed by a clock signal and two multipliers (D.A.C.1, D.A.C.2) which are fed by the binary counter (11) and a reference signal. An adjustable feedback network (30) is arranged to combine a fraction of the output of the multipliers (V.sub.1, V.sub.2) with the reference signal so that the output of the multiplier represents unequal steps of a staircase waveform. A switching network (13) under the control of the counter (11) applies to the windings drive signals in accordance with the output of the multipliers.Each winding has its own amplifier (15,17) to control its current, and pairs of antiphase signals from the switching network (13) are combined in the amplifiers to produce symmetrical changes of current in a respective pair of coils (1 and 2 or 3 and 4). The feedback network (30) distorts the otherwise linear outputs from the multipliers (D.A.C.1, D.A.C.
    Type: Grant
    Filed: December 7, 1979
    Date of Patent: August 11, 1981
    Assignee: The Monotype Corporation Limited
    Inventor: Raymond W. Throssell