Patents by Inventor Denis D. Shah

Denis D. Shah 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).

  • Patent number: 4785915
    Abstract: A hydraulic elevator system for monitoring a cold oil thermostat mounted on a hydraulic oil reservoir to prewarm the oil prior to passenger service by recirculating the oil in the reservoir through a pumping path which goes past up and down valves, thus bypassing the hydraulic jack. A control circuit including a microprocessor generally controls all car and corridor functions and is photo-coupled to the thermostat for an input signal which interacts with a program module in a random access memory which is run in sequence by the microprocessor. The program module provides a minimum timer phase for pump motor energization which is short but normally adequate to circulate the oil to standard minimum operating temperature before the sequencing activates a maximum timer phase which is cumulative in time for continuous bypassing until shutdown. The tiered total timer counting thus prevents overtemperature problems to avoid damage to the pump motor windings if the thermostat fails and also prevents recycling.
    Type: Grant
    Filed: June 19, 1987
    Date of Patent: November 22, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Denis D. Shah, Richard L. Thomas
  • Patent number: 4766978
    Abstract: An elevator control system and method for efficient failure control of block operation with a local area network on the traveling cable and distributed electronic control circuits in the car and proximate to the respective floors with a remote microprocessor controller for each car. A local area network also provides communication with the corridor fixtures in a serial signal format of input and output signals. Each remote controller includes a microprocessor based computer circuit which normally communicates over a multicar-link with the other and also over the local area networks for car and hall calls. Each controller implements an adaptive time based block operation with the total building being serviced, despite partial or total failure of communication between the controllers and the corridor fixtures, which would otherwise degrade the bank operation sooner and more restrictively.
    Type: Grant
    Filed: October 16, 1987
    Date of Patent: August 30, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Jeffrey W. Blain, Denis D. Shah
  • Patent number: 4765442
    Abstract: An elevator control system and method for efficient failure control with a local area network on the traveling cable and distributed electronic control circuits in the car and proximate to the respective floors with a remote microprocessor controller for each car. A local area network communicates with the corridor fixtures in a serial signal format of input and output signals. Each remote controller includes a microprocessor based computer circuit which communicates over a multicar-link with the other and also over the local area networks for car and hall calls to implement an expanded control strategy with interactive program modes with least restrictive capability. This program interacts with programs for floor control strategy and bank control strategy for the elevator system to select the best car and the most efficient operation, despite failures which would otherwise degrade the bank operation sooner and more restrictively.
    Type: Grant
    Filed: October 16, 1987
    Date of Patent: August 23, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Jeffrey W. Blain, Denis D. Shah, Jean Chen