Patent ID: 6129319
Filing Date: 2000-10-10
Classification: A61B,F16M,F21L,F21V,F21W,G02B

Abstract:
An adjustable counter-balanced stand to hold a load in a user-selected position, said stand comprising:a foot;a pedestal extending vertically from said foot, said pedestal having a lower non-tilting portion and an upper tilting portion;a load arm for supporting said load;a first pivot means for connecting said load arm to said upper tilting portion to permit said load arm to pivot about a first horizontal axis relative to said upper tilting portion;a second pivot means for connecting said upper tilting portion to said lower non-tilting portion to permit said upper tilting portion to pivot about a second horizontal axis relative to said lower non-tilting portion;a third pivot means arranged to permit at least said upper tilting portion to be rotated about a vertical axis;a first balancing arm paired with said load arm;a second balancing arm paired with said upper tilting portion;a first counterweight supported by said first balancing arm, said first counterweight corresponding in weight to an absolute weight of said load;a second counterweight supported by said second balancing arm, said second counterweight corresponding in weight to a combined absolute weight of said load arm, said first balancing arm, said load, and said first counterweight;said first balancing arm including a first positioning means for automatically moving said first counterweight relative to said first balancing arm;said second balancing arm including a second positioning means for automatically moving said second counterweight relative to said second balancing arm;a measuring means for detecting imbalance due to changes in said load and generating a signal representative of said imbalance; andremote control means connected to said measuring means and to said first and second positioning means for evaluating said signal and actuating said first and second positioning means to automatically move said first and second counterweights to approximately eliminate said imbalance.