Appliance lock with mechanical door sensor

摘要

A locking latch for an appliance provides an improved three-wire interface that reduces the chance of malfunction if the door is forcibly opened when it is in the lock state and a bi-stabile actuator is used. In one embodiment, the door switch is positioned to disengage the major load of the washing machine when the doors open, regardless of the lock or unlock state.

主权项

1. A door lock for a door of an appliance, comprising:
a housing attachable to the appliance near the door, the housing supporting and exposing only three connection conductors, the three connection conductors for attaching the door lock to other electrical components of the appliance including a first connection conductor connectable to an appliance motor and a second connection conductor connectable to a power source, the housing holding: a door position detector positioned to respond to a closure of the door when the housing is mounted to the appliance; a bi-stable electrical actuator for actuating a door locking element of a latch retaining the door when the housing is mounted to the appliance, the bi-stable electrical actuator communicating with the door locking element to both move the door locking element between a first state locking the door locking element and a second state releasing the door locking element in response to current flowing between only two connection conductors; and a lock sensing switch opening in response to a positioning of the door locking element in the second state, the lock sensing switch connected to the first connection conductor; and wherein the door lock, when communicating with the other electrical components of the appliance only through the only three connection conductors, is adapted to: (i) move the bi-stable electrical actuator between the first state and the second state when the door is closed; and (ii) block power to the appliance motor of the appliance through the first connection conductor whenever the door is open as sensed by the door position detector; and (iii) supply power to the motor appliance motor through the first connection conductor when the door is closed, the supplied power not passing through the bi-stable actuator.