Patent ID: 6901840
Filing Date: 2005-06-07
Classification: F15B

Abstract:
1. A fluid-powered mechanical actuator having a proximal end and a distal end and comprising a plurality of hollow tubular elements hingedly connected in end-to-end linked relationship to form a variable angle therebetween, each such link having one degree of freedom, means, to bias said elements in a direction to minimize said angle, a flexible elongated chamber enclosing a space within it, said chamber situated within linked said tubular elements and within the link therebetween, substantially contained thereby, said chamber having a flexible but non-expansible wall, and means to provide to the space within said chamber a pressurized working fluid, whereby increasing the pressure of said working fluid causes said chamber to straighten within said tubular elements, especially at said links, thereby moving the relative position of said tubular elements in a manner to act always against said biasing means, thereby to cause an increase of said angle with an increase in working fluid pressure, and whereby decreasing said pressure allows said biasing means to cause a decrease said angle and whereby controlling said pressure can be used to balance said biasing means to stabilize said angle at an intermediate position.