Counterbalance mechanism for incubator hood

摘要

A counterbalance mechanism is disclosed for offsetting the normal gravitational forces exerted on a rotatable cylindrical hood for an incubator. The mechanism includes a specially shaped cam that is fixed with respect to the rotatable hood. A cam follower, mounted on a slide movable with the rotatable hood, is spring biased against the cam. As the rotatable hood is moved to various positions, the spring loading and cam profile coact to produce a counter-rotational force that is opposite and equal to the force of gravity acting upon the hood at any point in its rotation. One or more detents is provided in the cam at predetermined positions such that the cam follower can be positioned within one of the detents at one or more desired positions of hood rotation such that the hood may be held at that selected position.