Abstract: An apparatus including a controller, a workpiece transport in communication with the controller having a movable portion and a transport path, and a multi-dimensional position measurement device including at least one field generating platen attached to the movable portion and at least one sensor group positioned along the transport path and in communication with the controller, the field generating platen is configured for position measurement and propelling the movable portion, each sensor in the at least one sensor group is configured to provide but one output signal along a single axis corresponding to a sensed field generated by the at least one field generating platen and the controller is configured calculate a multi-dimensional position of the movable portion based on the but one output signal of at least one of the sensors in the at least one sensor group, the multi-dimensional position including a planar position and a gap measurement.

Abstract: An apparatus including a controller, a workpiece transport in communication with the controller having a movable portion and a transport path, and a multi-dimensional position measurement device including at least one field generating platen attached to the movable portion and at least one sensor group positioned along the transport path and in communication with the controller, the field generating platen is configured for position measurement and propelling the movable portion, each sensor in the at least one sensor group is configured to provide but one output signal along a single axis corresponding to a sensed field generated by the at least one field generating platen and the controller is configured calculate a multi-dimensional position of the movable portion based on the but one output signal of at least one of the sensors in the at least one sensor group, the multi-dimensional position including a planar position and a gap measurement.

Abstract: An apparatus including a controller, a workpiece transport in communication with the controller having a movable portion and a transport path, and a multi-dimensional position measurement device including at least one field generating platen attached to the movable portion and at least one sensor group positioned along the transport path and in communication with the controller, the field generating platen is configured for position measurement and propelling the movable portion, each sensor in the at least one sensor group is configured to provide but one output signal along a single axis corresponding to a sensed field generated by the at least one field generating platen and the controller is configured calculate a multi-dimensional position of the movable portion based on the but one output signal of at least one of the sensors in the at least one sensor group, the multi-dimensional position including a planar position and a gap measurement.

Abstract: An apparatus including a controller, a workpiece transport in communication with the controller having a movable portion and a transport path, and a multi-dimensional position measurement device including at least one field generating platen attached to the movable portion and at least one sensor group positioned along the transport path and in communication with the controller, the field generating platen is configured for position measurement and propelling the movable portion, each sensor in the at least one sensor group is configured to provide but one output signal along a single axis corresponding to a sensed field generated by the at least one field generating platen and the controller is configured calculate a multi-dimensional position of the movable portion based on the but one output signal of at least one of the sensors in the at least one sensor group, the multi-dimensional position including a planar position and a gap measurement.

Abstract: A bus powered device includes a signal processing control circuit connected to and powered by a bus at a predetermined operating current and a bus current modulator circuit interconnected in series with a signal processing control circuit to the bus for providing a bipolar communication signal having an average current of substantially zero; the total series current of both the circuits is only the current required by the signal processing control circuit or the absolute value of the most negative current excursion during communication, whichever is greater.

Abstract: A bus powered device includes a signal processing control circuit connected to and powered by a bus at a predetermined operating current and a bus current modulator circuit interconnected in series with a signal processing control circuit to the bus for providing a bipolar communication signal having an average current of substantially zero; the total series current of both the circuits is only the current required by the signal processing control circuit or the absolute value of the most negative current excursion during communication, whichever is greater.

Abstract: A variable orifice valve for controlling fluid flow in a conduit, comprising a band or other movable members defining an opening for passing the fluid therethrough, the band mounted transverse to the direction of fluid flow in the conduit, so that the band opening is at least partially in the conduit. The band is movable relative to the conduit, to change the amount of the opening exposed to fluid flow.

Abstract: A thermocouple pressure gauging system for measuring partial vacuum is provided which uses time multiplexing to alternately heat the thermocouple to constant temperature and then measure the EMF from thermocouple with heating current off. A signal proportional to pressure is derived from the heating duty cycle. The pressure signal is in turn used to derive a reference signal which is compared to the EMF from the thermocouple to control the heating of the thermocouple.

Abstract: An intrusion detection system is disclosed for safeguarding an operator of an industrial machine such as a press brake. A light screen barrier (420) comprises sequentially pulsed beams (422) which are spaced far enough apart to permit penetration by a work piece (144) without obstructing more than one beam whereas penetration by the operator's hand will obstruct at least two adjacent, successively pulsed beams. A pulse train of regularly spaced signal pulses (BRS) with each pulse corresponding to a light beam is produced when none of the light beams are obstructed. A missing pulse detector (600, 40') with a logic circuit (502) produces a control signal for stopping the machine only when two or more adjacent light beams are obstructed causing two or more successive missing pulses in the pulse train.

Abstract: A switching circuit is disclosed for eliminating the effects of contact bounce in a movable contact switch connected between a voltage source and the input of a switching transistor. When the movable contact switch is closed, bouncing of the contacts undesirably produces a momentary voltage pulse which may produce false switching of the switching transistor. To avoid false switching, a coupling circuit is connected between the movable contact switch and the input of the transistor switch and includes a time constant circuit which has a different time constant for a positive going control voltage than for a negative going control voltage. The time constant circuit has longer time constant for a pulse of the polarity of the aforementioned momentary pulse than for the opposite polarity pulse whereby the transistor switch is prevented from responding to the momentary pulse.

Abstract: A method of improving the accuracy of scale readings featuring exciting the molecules of the supporting spring and clamping structure of the scale. The purpose of this excitation is to reduce the effects of hysteresis, creep and drift upon the measured load. Exciting the molecules of the support spring causes the scale to reach its stable state of stress much more rapidly. This results in obtaining more accurate weight readings for a load being weighed.