Patents by Inventor David B. Curtis

David B. Curtis 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).

  • Door latch assembly for roll-up doors
    Patent number: 6719334
    Abstract: A door latch generally comprising a latch cover and a latch slide. The latch cover comprises a upper angled section having a vertical portion and an angled portion extending therefrom, at least one first aperture defined in the vertical portion, at least one first slot defined in the angled portion, a horizontal portion having at least one second slot defined therein, and, at least one third slot defined therein substantially aligned with the first slot, a vertical middle section having a second aperture defined therein, and, a slide guide extending from one side, the slide guide having an upper spacer leg and, a lower spacer leg, an angled lower portion having a vertical edge, the vertical edge having at least one fourth aperture defined therein.
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: April 13, 2004
    Inventor: David B. Curtis
  • Reduced pull chain drive for roll-up doors
    Publication number: 20030197160
    Abstract: A reduced pull chain hoist comprising a frame having a pair of bearings for receiving a hexagonal shaft, a chain guide, a chain pocket wheel for turning a chain and a spur gear. A conventional curtain roll-up door is operated by pulling the chain which turns the chain pocket wheel, shaft and spur gear. The spur gear engages a ring gear mounted to a drum assembly. As the spur gear turns the ring gear and drum assembly and causes the door to raise or lower.
    Type: Application
    Filed: April 23, 2002
    Publication date: October 23, 2003
    Inventor: David B. Curtis
  • Tension device for live axle doors
    Patent number: 5778490
    Abstract: A live axle tension device (15) that is suitable for adjusting the setting of a spring (16) on a live axle door (10). The tension device comprises a spring (16) that connects to a drum wheel (14) and to a spring connecting plate (22). The spring connecting plate (22) is attached to the outside of an axle housing tube (24) that houses the axle (12). The axle housing tube (24) also has two tension plates (26) connected to it which sandwich a tension bracket (20). The tension bracket (20) is fixedly attached to a supporting structure (21) and the axle (12) is free to rotate inside the bracket. The axle housing tube (24) and the plates attached to it can rotate relative to the tension bracket (20). With the spring (16) connected to the drum wheel (14) at one end and connected to the spring connecting plate (22) at the other end, the insertion of a tension pin (32) through the tension plates (26) and the tension bracket (20) fixes the position of the two ends of the spring (16) relative to each other.
    Type: Grant
    Filed: January 24, 1996
    Date of Patent: July 14, 1998
    Inventor: David B. Curtis