Patents by Inventor Mark Levental

Mark Levental 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: 4535324
    Abstract: An alarm activator in the form of a ring-transmitter can be squeezed readily to activate an alarm by either ultrasonic or radio or infrared waves. The ring consists of either an ultrasonic or radio or infrared transmitter in a casing welded on an incomplete ring. Inside the casing is located a power source, a time delay circuit, an oscillator, a timer and either an ultrasonic or radio or infrared transducer. The tips of the incomplete ring are provided with two conductors, e.g. silver plates, one on each tip, forming a normally open contact. An all-around clearance is provided between the casing and the ring to permit the compression of the ring without interference from the casing to close the normally open contact and to permit current to flow from the power source through the time delay, energizing the timer which in turn will turn on the oscillator for a short time.
    Type: Grant
    Filed: July 12, 1982
    Date of Patent: August 13, 1985
    Inventor: Mark Levental