| 摘要 |
A cylindrical body has a first part-spherical socket portion in the top, fittingly receiving a ball. A ball retainer has a second part-spherical socket portion facing the first part-spherical socket portion and receiving the ball therein. A post has a proximal end fixed to the ball and extends radially outward from the ball and away from the body to a distal end, and has screw threads at the distal end to receive a fastener thereon for attachment of an object to the distal end of the post. The ball-in-socket mounting of the post enables freely swiveling the ball and thereby the swiveling the distal end of the post to an infinite number of loci in a spherical envelope centered at the center of the ball, as well as enabling the post, and any object mounted to the post, to be rotated on a radial line from the center of the ball to the location of mounting of the object to the post. The body has a hydraulic cylinder in the bottom receiving a piston. The piston is connected to the ball retainer for clamping the retainer on the ball and thereby locking the ball in the socket portions, to lock the post and thereby the object mounted to the post, in a position and orientation in space as selected by the user. A hydraulic pump assembly is coupled to the body to apply and release pressure on the piston. |
