Arm device for adjustable positioning of a medical instrument or the like

An articulated instrument-supporting device for placement and manipulation of an instrument within a predetermined region of space, comprising

• a set of device arm components, arranged in series and extending from a proximal support base, at least a pair of adjacent said arm components joined at an articulating joint,
• said articulating joint comprising a first rigid joint element joined to a first arm component and a second rigid joint element joined to a second arm component adjacent to said first arm component, said first and second rigid joint elements defining opposed joint surfaces which define, with a surrounding housing, a joint capsule, and seal means disposed between said joint surfaces and said housing, said first and second joint elements adapted for axial movement within said housing, between a first mode position and a second mode position,
• means at a distal end of said device for receiving and gripping an instrument,
• a source of fluid pressure comprising a vacuum,
• conduit means for connecting said joint capsule to said source of fluid pressure,
• means for selective actuation of the connection between said joint capsule to said source of fluid pressure,
• in a first mode, said means for selective actuation obstructing the connection of said joint capsule to said source of fluid pressure, thereby to permit relatively free motion of said first and second arm components about said joint for macro-adjustment of an instrument supported by said device, and,
• in a second mode, said means for selective actuation freeing the connection of the source of fluid pressure and said joint capsule in a manner to cause said first and second rigid joint elements to move axially for frictional engagement of surfaces of said joint elements upon said seal means in a manner to frictionally set the relative positions of said first and second arm components with a lightly loaded restraint of value selected to support an instrument within a predetermined region of space, the value of restraint by frictional engagement of said surface upon said seal members being further selected to allow a user to micro-adjust instrument position by application of light adjusting force to the instrument, the device supporting the instrument in the new position upon release of the light adjusting force.

An articulated instrument-supporting device for placement and manipulation of an instrument within a predetermined region of space, comprising

• a set of device arm components, arranged in series and extending from a proximal support base, adjacent arm components of said set joined at at least two articulating joints,
• each said articulating joint comprising a first rigid joint element joined to a first arm component and a second rigid joint element joined to a second arm component adjacent to said first arm component, said first and second rigid joint elements defining opposed joint surfaces which define, with a surrounding housing, a joint capsule, and seal means disposed between said joint surfaces and said housing, said first and second joint elements adapted for axial movement within said housing, between a first mode position and a second mode position,
• means at a distal end of said device for receiving and gripping an instrument,
• conduit means for connecting each said joint capsule to a source of fluid pressure,
• means for selective actuation of the connection between each said joint capsule to said source of fluid pressure, said means for selective actuation, in a first mode of each said joint capsule, obstructing the connection of said joint capsule to said source of fluid pressure, thereby to permit relatively free motion of said first and second arm components about said joint for macro-adjustment of an instrument supported by said device, and said means for selective actuation, in a second mode of each said joint capsule, freeing the connection of the source of fluid pressure and said joint capsule in a manner to cause said first and second rigid joint elements to move axially to engage upon said seal means thereby to set the relative positions of said first and second arm components with a lightly loaded restraint of value selected to support an instrument within a predetermined region of space and to allow a user to micro-adjust instrument position by application of light adjusting force to the instrument, the device supporting the instrument in the new position upon release of the light adjusting force, said means for selective actuation having at least three selectable conditions in which, respectively, two joints are selected to the first mode of operation, both joints are selected to the second mode of operation, and a given one of said joints is selected to the first mode and the other joint is selected to the second mode of operation.