An integral motor controller circuit for supplying variable speed, bidirectional drive to a motor as a function of variations of a sensed parameter includes an amplifier circuit which is responsive to an error signal indicative of deviations of the parameter from a set point to provide an output signal representing the direction and amount of the deviation. The amplifier output signal is applied to a first motor terminal and to an input of a two-level comparator circuit which is responsive to an...

A d.c. control circuit includes a slew-rate limiting circuit interposed between a current sensing device which detects current in a load and a control circuit, for switching on and off a thyristor controlling current through the load. The circuit limits the slew rate to a level in excess of the maximum normal current slew rate through the load.

The present invention relates to a lighted electrical pushbutton switch which may be utilized with only slight modification to switch either one or two normally open circuits. The movable contact member comprises an octagonal-shaped plate that carries at least two pairs of deflectable contacts and a pair of guide wings. The movable contact may be modified for two circuit operation by dividing the contact member into two sections and by providing an insulating support member. The actuating pushbu...

A control circuit for reversibly driving a motor from a small d-c voltage. A switched a-c voltage source is selectively applied to the primary windings of either of two voltage step down transformers. The a-c voltage of each secondary winding is rectified and applied to the motor through a series resistor. The rectified voltage from one transformer drives the motor in one direction and the rectified voltage from the other transformer drives the motor in the reverse direction.

A plural phase stepping motor control circuit in which damping is accomplished by energizing a previously energized phase prior to the expiration of the power cycle on a pair of other phases. The duration of the damping pulse is inversely proportional to the speed of operation. The logic involved allows for forward or reverse running. A sprocket latch circuit locks out spurious overshoot responses, such as may be caused by vibration, damaged tape, or other irrationality.

A monitoring system for off-site monitoring, traffic study and/or trouble shooting of elevator installations. Communication between the remote monitoring site and a selected elevator installation is established via a direct dial telephone link. The remote monitoring site includes visual display means for displaying the operation of the selected elevator installation in real time, means for storing and analyzing status signals from the elevator installation, as well as for printing out the result...

Apparatus to control the direction of movement of a mechanism over a surface. The surface is provided with a plurality of substantially parallel strips of conductive material alternately connected to opposite terminals of a source of current supply. The mechanism has a plurality of conductive discs or wipers so disposed that at least two of the wipers contact a pair of the conductors which are each connected to oppositely disposed terminals. The mechanism also has driving means such as wheels fo...

An improved technique is disclosed for adjusting the crankshaft angle of each of a plurality of synchronized tandem-coupled presses with respect to a reference shaft angle. At the start of adjustment, a plurality of first motors that synchronously drive the successive crankshafts during normal press operation are disengaged from the crankshafts and maintained operative with undiminished speed. A plurality of second motors operative at a speed slightly greater than the speed of the reference shaf...

On vehicles such as snowmobiles or other devices utilizing a internal combustion engine, it is usual to provide a throttle lever which is squeezed to open the throttle and released to close the throttle. Various forms of engine kill mechanisms are provided to stop the engine when the throttle pressure is released. These are usually provided with a mechanism for cutting out the kill switch for starting purposes and these are easily by-passed. The present device includes a relatively simple constr...

A process for generating energy by utilizing the osmotic pressure resulting when two liquids having different chemical potentials are each placed in contact with opposite sides of the same semipermeable membrane. The process is particularly applicable to the production of energy from the system sea water/fresh water. The sea water is in the form of an enclosed body having an outlet orifice in communication therewith. The fresh water passes through the semipermeable membrane causing the osmotic p...