Supervised alarm system

A warning unit comprising:

• a housing;
• a DC motor in said housing and including a rotatable shaft with a disc mounted thereon and rotatable therewith, said shaft and said disc defining an axis of rotation;
• a rigid arm coupled to said disc transverse to said axis of rotation so as to reciprocate when said disc rotates, said arm adapted to be coupled to a piece of furniture so as to shake the piece of furniture upon reciprocating movement of said arm;
• an AC to DC conversion circuit within said housing and electrically connected to an external AC power source, said AC to DC conversion circuit having a DC output;
• a control circuit within said housing and electrically coupled to said DC output of said AC to DC conversion circuit for receipt of DC power therefrom, said control circuit coupled to said DC motor and including an activation input for receiving an activating signal from an external activating device, said control circuit turning on said motor which rotates said shaft and said disc when the external activating device provides said activating signal;
• a rechargeable battery electrically coupled to said control circuit to provide backup power thereto upon an external AC power source failure;
• an autoswitching circuit within said housing and electrically coupled to said control circuit, said autoswitching circuit allowing energy from said battery to power said circuits upon a loss of the external AC power source, and allowing energy from the external AC power source to power said circuits and cutting off said battery power upon restoration of the external AC power source;
• and
• a supervision circuit within said housing and electrically coupled to said control circuit, said supervision circuit monitoring the external AC power source and said battery for inoperativeness and providing an alarm indication signal upon finding any such inoperativeness.