Patent ID: 8123428

Claim:
An apparatus for locking an inner telescoping member into a desired position within an outer telescoping member, the apparatus comprising: an outer tubular telescoping member comprising first and second locking pin engagement holes; an inner tubular telescoping member receivable within the outer telescoping member for relative motion along a longitudinally extending central apparatus axis; and a locking mechanism carried by the inner telescoping member and including: a lock housing carried by the inner telescoping member and configured to be receivable within the outer telescoping member for relative motion along the central apparatus axis with the inner telescoping member, a first locking pin carried by the lock housing in a position alignable with the first locking pin engagement hole in the outer telescoping member and supported for motion between a retracted position within the housing and an extended position in which the first locking pin protrudes outwardly from the housing and engages the first locking pin engagement hole in the outer telescoping member, a first biasing member carried by the housing and positioned to resiliently bias the first locking pin toward its extended position, a second locking pin carried by the lock housing in a position alignable with the second locking pin engagement hole in the outer telescoping member and supported for motion between a retracted position within the housing and an extended position in which the second locking pin protrudes outwardly from the housing and engages the second locking pin engagement hole in the outer telescoping member, a second biasing member carried by the housing and positioned to resiliently bias the second locking pin toward its extended position, and a synchronizing ring carried by the housing and supported for rotational motion about a ring rotational axis and operatively connected to the first and second locking pins wherein depression of one of the locking pins rotates the synchronizing ring in a disengagement direction thus withdrawing the other locking pin toward its retracted position.