Massachusetts Institute of Technology

Other

Pepsico, Inc.

International Totalizing Systems, Inc.

Lutron Electronics Company, Inc.

International Totalizing System

David M Otten

David J Perreault

Gerald L Wilson

Martin F Schlecht

Khurram K Afridi

Leo Francis Casey

John G Kassakian

Thomas Hamilton Warner

Victor S Lerman

Seungbum Lim

Amy Battles

Don Lee

Benjamin Linder

Harry H Lerman

Anthony J Caloggero

Juan A Santiago-Gonzalez

Bruce Rhodes

Neil Rasmussen

John Ofori-Tenkorang

Leo Casey

A circuit includes a reconfigurable rectifier, a voltage balancer, and a pair of converters. The reconfigurable rectifier includes an ac input port and three output ports. In a first configuration, the reconfigurable rectifier can deliver power at a first output port and, in a second configuration, to at least a second output port. The voltage balancer includes first and second ports coupled to second and third output ports of the reconfigurable rectifier and is configured to balance received voltage at the first and second ports. The first converter has an input coupled to the first port of the voltage balancer and an output at which a first converted voltage signal is provided. The second converter has an input coupled to the second port of the voltage balancer and an output at which a second converted voltage signal is provided.

High-frequency, high density power factor correction conversion for universal input grid interface

A power converter circuit rectifies a line voltage and applies the rectified voltage to a stack of capacitors. Voltages on the capacitors are coupled to a plurality of regulating converters to be converted to regulated output signals. The regulated output signals are combined and converted to a desired DC output voltage of the power converter. Input currents of the regulating converters are modulated in a manner that enhances the power factor of the power converter.

Method and apparatus to provide power conversion with high power factor

A shifting mechanism for a bicycle or other wheeled cycle has at least two gear wheels, of which at least one is segmented. The segments are movable into and out of a driving position. Motion of the segments occurs at a circumferential location out of the driving zone, at a location where the driving band, typically a chain, is not contacting the segment. The shifting mechanism can be provided at the front chain ring, or at the rear, gear sprocket. For a front chain wheel, the free zone is generally the rearward half of the chain ring, while for the rear gear sprocket, the free zone is generally the forward half. The moving segments can be toothed gates which flip perpendicularly to the plane in which the chain resides. The gates may be actuated by a moving mechanism powered by an actuator, such as a D.C. motor, under control of a signal processor, such as a microprocessor. The signal processor also takes as an input a speed signal based on the rotational speed of the cycle wheels, or the cadence of the pedal or a combination thereof.

Automatic transmission for a cycle, such as a bicycle, and a cycle having such as transmission

A centrifuge rotor cover assembly for use with a centrifuge having a rotor and a housing enclosing the rotor and including a lid movable between a closed position overlying the rotor and an open position providing access to the rotor. The cover assembly includes a rotor cover removably coupled to the lid. Means are provided for engaging the rotor cover with the rotor for rotation therewith and for uncoupling the cover from the lid in response to the lid being moved to the closed position. Means are also provided for disengaging the rotor cover from the rotor and for coupling the cover to the lid in response to the lid being moved to the open position. In another embodiment of the present invention there is provided a locking centrifuge rotor cover that includes a locking mechanism having at least one locking element which engages a locking portion of the rotor so as to lock the cover onto the rotor, the locking element being responsive to centrifugally induced forces during rotation of the rotor for increasing the locking force between the cover and rotor. In a further embodiment of the present invention there is provided a centrifuge rotor cover locking hub which includes a hub housing having an upper portion and a lower portion, the upper portion being supported by the lid and the lower portion being adapted to releasably support the cover. A locking mechanism is disposed within the hub housing which locks the cover to the rotor in response to the cover being engaged with the rotor.

Locking centrifuge rotor cover assembly

A plastic number plate cover that can be installed from the exterior of the housing faceplate of a public telephone and which is resistant to tampering. The cover includes an envelope-shaped pocket into which a number plate or card is inserted, and opposed cantilever arms each terminating in a tab having a beveled edge. The cover is inserted into a rectangular-shaped recess on the faceplate when the tabs are brought into contact with a recess edge, causing the arms to flex and allowing the beveled edges to slide past the recess edge. The cover may be fixed or removable once installed within the faceplate, depending on the structure of the tabs.

Snap-in cover for a payphone number plate

A circuit for sensing the state of a potentiometer includes a capacitor that is connected to the potentiometer wiper and that is successively charged by applying a voltage to each end of the potentiometer resistive element. The capacitor is discharged between successive chargings. The times needed to charge the capacitor to a predetermined voltage in each case are used to determine the position of the wiper along the resistive element. The circuit can be connected to a plurality of potentiometers, any one of which can be selected and the wiper position determined. A similar circuit can determine the state of an inductive or capacitive voltage divider.

Potentiometer state sensing circuit

An auditor system (10) includes a control circuit (30) that employs an off-hook detector (32) connected across the tip and ring lines (12 and 14) of a coin telephone to determine whether the coin telephone is off hook. It also employs a step-pulse detector (36) connected across the step relay terminals of the coin telephone, accept-pulse and reject-pulse detectors (40 and 42) connected across its accept/reject relay terminals, and a coin contact sensor (48) connected across its coin-contact terminals to keep track of the number of coins of each denomination accepted by the coin telephone. When the auditor system determines that the coin receptacle has collected a predetermined volume of coins, it connects a high-current power supply (18) across the tip and ring lines and thereby powers a transmitter (68) that sends dialing signals over the telephone lines to call up a data-collection computer at a remote location. Upon detecting, by means of a tone receiver (72), that the call has been answered, it employs the transmitter to send a request that the money in the coin telephone be collected. It also sends other information at the same time and receives information from the central computer for resetting some of its registers. Through the use of this type of auditor system, there is no need for the central computer to poll auditors at a number of coin-telephone locations, separate data lines are not needed, and the amount of communication over existing lines is kept to a minimum so that telephone traffic is not unduly increased.

Coin-telephone auditor

A vending machine control circuit having a plurality of capacitively coupled switches for enabling a customer to indicate his choice of a product to be vended. A logic circuit is responsive thereto for controlling the vending of products by the generation of vend signals directed to a plurality of vend solenoids. Out-of-product switches are wired in series with the vend solenoids such that if a solenoid is activated, but no current flows therethrough, a current sensing circuit is utilized to detect that the product is out-of-stock. This is a significant improvement over prior art control circuits, particularly from the standpoint of decreased wiring requirements in the vending machine. The control circuit has an early power failure detecting circuit which allows critical tasks within the machine to be finished prior to removal of the power. This feature allows the machine to shut down in an orderly manner, and enables the totalizer to maintain track of sales even in the event of a power failure. Software within the processor directs the overall operations of the control circuit, including the vend operations, the coin receipt and dispensing functions, and also the cash and product totalizing functions.

Vending machine control circuit

A dc ground fault detector in which ground fault is sensed by noting an imbalance of magnetic flux due to a pair of windings on a toroidal core.

DC Ground fault detector wherein fault is sensed by noting imbalance of

An automatic switching matrix that includes an apertured matrix board containing a matrix of wires that can be interconnected at each aperture. Each aperture has associated therewith a conductive pin which, when fully inserted into the associated aperture, effects electrical connection between the wires within that particular aperture. Means is provided for automatically inserting the pins in a determined pattern and for removing all the pins to permit other interconnecting patterns.

Automatic switching matrix

A power angle relay to measure the power angle of a synchronous alternator. The power angle relay receives a reference voltage signal corresponding to a fixed point on a reference voltage waveform (usually a zero crossing) from some point in the power system to which the alternator is normally synchronized and an electric signal representative of the angular position of the shaft of the synchronous alternator and is operable to combine the two to provide an indication representative of the power angle between the direct axis of the synchronous alternator and said fixed point.

Power angle relay to measure and respond to the power angle of a

A totalizer system having a first electronic device coupled to the vending machine for storing the number of vends (data) made by the vending machine, and a second device for interrogating the first device and providing a readout of said vends, e.g., in code, actual money value, or actual number of vends, or any form desired. The present system preferably includes an optical interrogation scheme using modulated light for transmitting stored vends in the first device to the second device thus eliminating human error, and an electronic memory in the first device that will store vends for a prolonged period of time even if the vending machine is unplugged.

Totalizer system

A totalizer for recording the income of a multiprice vending machine, the totalizer including a device to determine the value of the item selected, the fact that a sale was made, and a counter to total the value of all items selected. The totalizer preferably verifies the correctness of the value of the item selected to prevent erroneous counts and also preferably generates a coded output signal representing the price line of the vending machine providing information.

Growing community of inventors

Newton, MA, United States of America

David M Otten