Patents by Inventor Robert L. Littwin, Sr.

Robert L. Littwin, Sr. 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: 4121865
    Abstract: A multipurpose lifting device with variable holding power to both electromagnet and vacuum cup pickup structure to eliminate any physical damage either external or internal to the workpiece by distortion, with a permanent magnet feature to be used as a standby safety, or used in conjunction with the electromagnet and vacuum cup structure to triple the lifting power per square inch of surface area when attached to the workpiece. This structure is a perfected device for picking up a plate or sheet of ferrous or non-ferrous material individually from a stack of same. The power to the unit can be variably controlled to eliminate distortion to the sheet or plate for transport with an independent self-regulating permanent magnet safety for ferrous metal. If all power to the apparatus fails, it will automatically retain the ferrous metal sheet indefinitely until it can be brought to rest in a safe position.
    Type: Grant
    Filed: December 9, 1976
    Date of Patent: October 24, 1978
    Inventor: Robert L. Littwin, Sr.