Adjustable safety interlock for microwave ovens

Claim 1

A microwave oven apparatus, comprising: (a) a cavity having walls defining a cooking enclosure and having an access opening; (b) an outer case disposed about a portion of the cavity; (c) a door for closing the access opening; (d) a microwave energy source adapted to radiate energy within the enclosure; (e) an electrical circuit for energizing the source and controlling the operation of the apparatus; (f) a switch for interrupting the electrical circuit and de-energizing the microwave energy source; (g) means for activating the switch upon closure of the door, wherein the activation means comprises a longitudinal member having its forward end connected to the door and a portion of its distal end disposed to contact the switch upon closure of the door, and a tension spring attached at one end of the distal end of the longitudinal member and at the other end to one of the cavity walls to urge the distal end into contact with the switch; (h) means for supporting the switch disposed between the cavity and the outer case so that relative movement between the swich and the activation means is permitted, wherein the support means comprises a first support bracket mounted on one of the cavity walls, and a second support bracket pivotally attached to the first support bracket on which the switch is mounted in a fixed position; (i) means for moving the switch relative to the activation means and for securing the switch in a selected position, wherein the movement means comprises: a first tab formed from the first support bracket and having a hole therein, a second tab formed from the second support bracket and having a hole therein, an adjusting bolt that slides through the holes in the tabs, and means for retaining the bolt in the first tab; a compression spring having one end pushing against the first tab and the other end pushing against the second tab to bias the switch means away from the activation means, whereby the contacting of the switch with the distal end of the longitudinal member is determined by the combination of the tension spring bias in conjunction with the longitudinal member, the compression spring bias between the first and second tabs, and the bias of the adjusting bolt; and (j) means for gaining access to the means for moving the switch after the outer case is positioned about the cavity, and means for closing the means for gaining access, wherein the means for gaining access comprises: a hole in the outer case, and a first wall extending beyond a second, abutting cavity wall and having a hole therein that is axially aligned with the hole in the outer case and said adjusting bolt.