Patents by Inventor Franz-Dieter Kaldewei

Franz-Dieter Kaldewei 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: 5335376
    Abstract: A whirlpool bathtub has a plurality of devices positioned in the tub wall and/or tub floor for generating water or water and air jets. Each device has a pump wheel positioned behind an impeller both facing the tub interior and fixed on a drive shaft of an electric motor capable of reversing motor rotation. When the electric motor rotates in one direction, the impeller aspirates water from the tub interior and returns the water through a central outlet as a water jet. When the electric motor is rotated in the opposite direction, both the impeller and pump wheel rotate where the pump wheel also aspirate water which is used to aspirate ambient air and then injected into the tub, thereby generating an air bubble massage. In other embodiments, the impeller free-wheels when the motor rotates in the opposite direction, and the impeller can aspirate air when the motor rotates in the one direction.
    Type: Grant
    Filed: November 9, 1990
    Date of Patent: August 9, 1994
    Inventor: Franz-Dieter Kaldewei