Patents by Inventor Walter W. H. Clarke

Walter W. H. Clarke 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: 4266415
    Abstract: A door lock, in particular a lock for hotel room doors. Actuation of the exterior door handle creates a supply of compressed air which is directed through a coding assembly to actuate a lock release member. The operation of the coding assembly is controlled by a pair of matching punched cards. One of the cards is normally positioned within the lock and the other card is retained by an authorized user for insertion into the lock to operate the coding assembly. Two separate coding assemblies are provided with a hotel door lock, one being for use by a guest and the other under the control of the hotel management.
    Type: Grant
    Filed: August 6, 1979
    Date of Patent: May 12, 1981
    Inventor: Walter W. H. Clarke