Abstract: A mousetrap having a lower jaw and an upper jaw pivotal relative to the lower jaw at hinge posts received in upwardly facing sockets. A single continuous garter spring surrounds the lower and upper jaws to hold the jaws together in an assembled relationship. The spring is secured to the lower and upper jaws such that the longitudinal centerline of the spring is aligned with or slightly behind the pivot axis of the upper jaw when the upper jaw is fully open. Thus, the spring exerts no closing force on the jaws in the open position thereof. The spring exerts such a closing force only when the upper jaw is rotated slightly forwardly by a trigger operated by the mouse in attempting to remove bait.

Abstract: A variable pitch diameter torque sensing pulley assembly which includes a first pulley half with a hub and a second pulley half mounted on the hub for axial and rotational movement. The assembly includes two sets of cams and a set of cam followers for biasing the pulley halves toward each other with a force which varies directly as the torque being transmitted by the pulley assembly varies. The two sets of cams are arranged so that one set of cams transmits torque when the pulley halves are close together and biases the pulley halves toward each other with a relatively small axial force based upon the torque being transmitted and the other set of cams transmits torque when the pulley halves are far apart and biases the pulley halves toward each other with a relatively large axial force based upon the torque being transmitted.