Abstract: A printer of the daisywheel type in which the existence of a carriage control signal and a printwheel control signal operate inhibiting apparatus for a control signal otherwise gated to a paper feed operator.
Abstract: A digital servo system adapted for use in a dual mode coarse-fine servo system to control a movable member from a starting position to an at rest destination position. The digital servo generates a pulse train in response to varying space phase cyclic analog position signal A from an encoder coupled to the movable member. Each cycle of an analog position signal represents a small incremental amount of movement by the movable member. The pulse train provides a change in its state in time with the varying position signals. In the preferred embodiment, eight changes occur per cycle. The pulse train is integrated to provide a velocity signal which is compared with a command velocity signal.
Abstract: A processing system adapted to control a sequential automated device to a state determined by the immediately preceding state. The system comprises a read only memory (ROM) (or alternatively a static RAM) having coded at each address in bit positions 2 through n the address of either the output signal to be controlled, the input signal to be sensed or the next ROM address. Bit position 0 indicates whether an output or input is to be selected and bit position 1 either determines the desired state of the input that is selected or routes the 2 through n bit position address to select the output or to set a new address for the ROM. Accordingly bits 0 and 1 from the ROM are combined with the selected input in a logical circuit comprising gates and inverters to either increment the ROM address buffer or jump to a new address.
Abstract: An optoelectronic device comprising a light-sensitive device which produces or modifies an electric current in dependence upon the intensity of light incident thereon, and a light-emitting device arranged to emit light in response to said electric current and so disposed that part of said emitted light is incident upon the light-sensitive device to provide positive feedback.
Abstract: Synchronizing apparatus is disclosed in accordance with the teachings of the present invention wherein the operation of a first device is regulated in accordance with the operation of a second device. The phase relationship between signals representing the operation of the first and second devices, respectively, is determined by comparison means which produces a pulse width modulated signal indicative of said phase relationship. Control signal generating means responds to the pulse width modulated signal to generate an analog signal having an amplitude established by said phase relationship. Feedback means, including variable frequency generating means, is controlled by the analog signal to modify the operation of the first device whereby said first device is urged into a synchronous relationship with said second device and the signals representative of the operation of said first and second devices admit of a desired phase relationship.
Type:
Grant
Filed:
November 16, 1970
Date of Patent:
January 20, 1976
Assignee:
Xerox Corporation
Inventors:
James M. Donohue, Joseph R. Kramer, Victor Rodek