Daniel D. Evans 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).
Abstract: An edge trimmer for trimming the side edges of a running length of metal strip having upper and lower rotary shearing cutter discs engaging the top and bottom respectively, of the strip being trimmer includes top and bottom cylindrical strip stabilizers mounted coaxially with the cutter discs engaging the top and bottom surface of the strip adjacent the trim line, and a movable holddown roll disposed inboard of the top strip stabilizer and cooperating with the lower strip stabilizer to stabilize the strip at a location spaced inward from the trim line. The holddown roll is movable between an operable position engaging the strip and an inoperable position permitting access to the cutter disc for servicing.
December 20, 1989
Date of Patent:
April 16, 1991
National Steel Corporation
Laurence C. Cox, Raymond Dugan, Daniel D. Evans, Robert Griffith, Terry L. Handley, Jeffrey J. Leeper
Abstract: A system bus (13) carrying multidimensional path data interfaces with a plurality of local microprocessors (24), one for each dimension, through a plurality of dual access memory structures (21), one for each local microprocessor (24). A local arbiter (35) controls access to each dual access memory structure (21), facilitating elimination of wait states in data transfers between the bus (13) and memory (21) and between the local microprocessor (24) and memory (21). The arbiter (35) is implemented using a programmable logic device state machine approach, which implements a mode of operation wherein the circuitry is armed for a transfer between a local microprocessor (24) and the dual access memory (21) and accomplishes such transfer with no wait states.
Abstract: A digital robotic axis controller which employs a digital processor to apply the inverse of a plant model transfer function to positional information representative of a target path to generate a feed forward position control signal and to combine an error signal with the positional information to generate a feedback control signal. The feed forward and feedback control signals are combined to produce a total position control signal which is supplied to a digital-to-analog converter and then to a plant comprising an amplifier, a motor for establishing the actual position of a robotic member, and an encoder for deriving the error signal from the motor position. In application, a number of such plants are controlled to achieve a coordinated multidimensional movement with increased accuracy.
Abstract: A digital servo system for causing a mechanical element (48) to track a desired path and hold various positions along the path and employing a lead/lag integrator (18) in parallel with a feedback control loop. The input to the integrator (18) is switched between velocity (V.sub.EK) error during pathtracking and position error (E.sub.K) during holding to increase the resistance of the mechanical element (48) to position changes caused by outside forces during both pathtracking and holding. The integrator function employed uses a term (U.sub.integrator(k-1)) representing a previous integrator output value to assist in smoothing perturbations caused by switching between position and velocity error.