Abstract: A system and method for defining specifications for outputting content to multiple formats. More specifically, a system and method for creating a single multi-purpose stylesheet file from a single user interface, the single multi-purpose stylesheet being capable of designing multiple output media formats. For example, the multi-purpose stylesheet may convert input XML content to HTML, PDF, PostScript, WML, or other output formats. The method may include creating or modifying a multipurpose stylesheet containing formatting rules corresponding to various properties of different output media formats. A user can configure the multi-purpose stylesheet by selecting different formatting properties for different output media formats.

Abstract: An improved electronic proximity sensor and crack detector that is primarily responsive to the induced resistance in a coil; including an LC resonating circuit that utilizes constant current and a DC power source. By sensing changes in the induced resistance, the invention detects various conditions of parts present and probe fault and can detect a crack in a rotating metal object that is in proximity with the probe. This is accomplished by sensing changes in the induced resistance that occur at the same frequency at which the metal object is rotating.

Abstract: A combination of a programmable logic controller with analog circuitry. The analog circuitry includes a summation point to which several items are coupled. Analog inputs are selectively coupled to the summation point through analog switches. Also, the output of a digital to analog converter couples to the summation point. Still further, the analog output for the controller is obtained from a sample and hold circuit which has its input connected to the summation point and which includes means for outputting the analog value at its output back to the summing point. Even still further, a comparator input couples to the summation point. The arrangement provides for direct processing of analog information either by direct output of analog processed analog data or by obtaining one bit data from the comparator which represents whether a threshold has been reached by the analog data.

Abstract: An induction motor circuit which effectively prevents voltage spikes caused by leakage inductance of the induction motor stator windings without otherwise interfering with the overall operation of the induction motor. The circuit incorporates two windings between a common point and the positive supply and two other windings between the common point and the negative supply. Voltage spikes are suppressed by diodes connecting directly from the ends of each of the windings to the supply terminals oriented to the opposite end of the respective windings.

Abstract: A transformer-coupled isolation amplifier which has a minimally sized transformer, high common mode rejection, and a highly linear response over a wide dynamic range. A first chopper periodically alternates by 180.degree. the connection of the input through a high resistance to the primary of a small square loop pulse transformer. The secondary, with the end of the winding closest to the primary grounded, has the inputs of an operational amplifier placed across it. Negative feedback is provided around the amplifier to provide an apparent very low impedance across the secondary of the transformer. The negative feedback induces a current in the transformer secondary which cancels the flux produced by current flowing in the primary, thereby allowing usage of the transformer normally suitable only for high speed pulses. The output of the amplifier connects to a second chopper synchronous with the first to generate the amplified analog signal.

Abstract: An energy management system for a group of electrical loads such as in an industrial plant. The electrical power usage by the group of loads is elastically maintained between an upper set point and a lower low limit point, which is a percentage of the set point, at all times. The electrical load demand is presented in the form of a demand count to a comparator whose output provides a load display and couples load information to a sequencer. The sequencer cycles those loads which are off through the group of controlled loads and also varies the number of off loads in response to the comparator information. The set point floats and is responsive to actual power demand and a memory may be utilized to affect the sequencer operation dependent upon preprogrammed instructions for particular loads on particular days.

Abstract: A circuit which effectively prevents voltage spikes caused by leakage inductance of the step motor windings without otherwise interfering with the overall operation of the step motor. The circuit incorporates two windings between a common point and the positive supply and two other windings between the common point and the negative supply. Voltage spikes are suppressed by diodes connecting directly from the ends of each of the windings to the supply terminals oriented to the opposite end of the respective windings.

Abstract: A programmable logic controller includes a plurality of input interfaces and a plurality of output interfaces for connection to industrial equipment such as automatic assembly equipment, textile machinery, materials handling equipment, and chemical processes. The input and output circuits can be randomly addressed as to their state through an eight bit bus, which connects in parallel with up to 16 groups of eight input and/output circuits. The controller includes groups of timers which are each manually adjustable as to the timing operation and which are sequentially addressed each time a timing function is called for by the program. The timers are designed to be cascaded in groups to virtually any number of timers. The controller includes a scratch pad memory, half of which retains memory upon power failure and half of which does not. The control of the controller by the operator is made more nearly foolproof by interlocking the operations of control switches.

Abstract: The present invention comprises computer system equipment useful for detection of faults in data transmission within a computer system. Fault detection is accomplished by monitoring the current flow through a digital signal source means, which is characterized in that it only draws significant current during a non-transition period when a fault condition occurs.

Abstract: A programmable logic controller includes a plurality of input interfaces and a plurality of output interfaces for connection to industrial equipment such as automatic assembly equipment, textile machinery, materials handling equipment, and chemical processes. The input and output circuits can be randomly addressed as to their state through an eight bit bus, which connects in parallel with up to 16 groups of eight input and/output circuits. The controller includes groups of timers which are each manually adjustable as to the timing operation and which are sequentially addressed each time a timing function is called for by the program. The timers are designed to be cascaded in groups to virtually any number of timers. The controller includes a scratch pad memory, half of which retains memory upon power failure and half of which does not. The control of the controller by the operator is made more nearly foolproof by interlocking the operations of control switches.

Abstract: An input converter circuit for producing a logic level indication of the on or off condition of an input. The input may be AC or DC at any reasonable level. A bilateral photocoupler output is applied to an operational amplifier integrator, which establishes the integration time of the signal. The amplifier output is coupled to a Schmitt trigger having threshold levels at about one third and two thirds of the power supply voltage. The output of the Schmitt trigger provides a logic one output if there is an input signal present and a logic zero output otherwise.

Abstract: An electrical load in series with a source of AC power is connected across the anodes of a triac with the secondary of a transformer being connected between the triac gate and one of the triac anodes. An electronic switch controls current flow in the primary of the transformer such that a negative voltage is supplied at the gate of the triac during conduction by the primary until saturation of the transformer occurs. After saturation, the electronic switch opens the transformer primary initiating a flyback period during which the triac gate potential rings positive and a consistent peak positive current is supplied to the triac gate from the secondary of the transformer. A half-wave rectifier circuit and transistor may be substituted for the triac for DC load control, or a pair of these transistor circuits may be connected in series to provide AC load control.