Patents by Inventor Calvin L. Hayes

Calvin L. Hayes 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: 4241838
    Abstract: A height-adjustable hoist having an upright post, a tip member extensible therefrom, and a sleeve swivelable about the axis of the post. A hoist arm is pivotally mounted at one of its ends on the sleeve for pivoting in a substantially upright plane between raised and lowered positions. A nonextensible chain extending from the other end of the hoist arm to the tip member is adjustably anchored to the tip member by a chain-engaging lock. To set the hoist arm at a desired raised position, the tip member is extended and the chain is selectively anchored to the tip member, with the chain stretched between the hoist arm and tip member.
    Type: Grant
    Filed: June 26, 1978
    Date of Patent: December 30, 1980
    Inventor: Calvin L. Hayes