De-energizing electrical safety circuit

Abstract

The present invention describes a de-energizing electrical safety circuit for appliances, in particular dryer machines wherein said circuit controls power supplied from a power source, via a power cord comprising a neutral line and at least one live input line connected to a neutral line and at least one charge powered line, respectively. The de-energizing electrical safety circuit comprises at least one normally open thermostat connected to two switches corresponding to a neutral line and a charge powered line; at least one thermostat is mounted within the cabinet external to the drum. The excess heat in the cabinet closes at least one thermostat thus closing the circuit and allowing the power to flow between the neutral line and the charge powered line causing a short circuit in at least one thermostat and then opening the switches and thereby achieving a complete de-energizing of the dryer machine.

1 . A dryer machine including a cabinet housing a drum and ducts associated therewith for directing air flow into and through the drum of said dryer machine to dry cloth items placed in the drum, wherein said dryer machine further includes a main harness supplying power to an electric charge characterized by:
 a) a power cord for supplying power from a power source to an electrical charge in the cabinet, the power cord comprising a neutral input line and at least one powered wire input line entering the cabinet;   b) the electrical charge being connected in circuit with the neutral input line of the power cord and at least one charge powered wire line;   c) a de-energizing electrical safety circuit for controlling the power supply from the power source to the electrical load, the de-energizing electrical safety circuit comprising a control circuit comprising two switches; one switch positioned between the neutral input line and a corresponding neutral line; and the other switch positioned between at least one powered wire input line and a corresponding charge powered wire line; said switches being preset normally closed in order to allow power to flow from the input line to the charge powered wire line or to the neutral line, as the case may be; and   d) the control circuit comprising at least one normally-open bimetal thermostat and mounted within the cabinet connected between the neutral line and at least one charge powered wire line, that upon reaching or exceeding its working temperature closes the circuit between the neutral line and the at least one charge powered wire line thus opening the normally-closed switches in order to disconnect the power between the neutral input line and its corresponding neutral line, as well as the power of the at least one powered wire input line and its corresponding charge powered wire line.   
     
     
         2 . The dryer machine according to  claim 1 , characterized in that:
 the de-energizing electrical safety circuit comprises a plurality of thermostats located in different areas of the cabinet and electrically connected in parallel with the switches.   
     
     
         3 . The dryer machine according to  claim 1 , characterized in that:
 at least one normally-open thermostat is preferably of a ceramics type, with a tripping temperature preferably higher than a temperature measured in normal operation or in tests regarding to the standard UL2158.   
     
     
         4 . The dryer machine according to  claim 1 , characterized in that:
 the terminal block of switches is located adjacent to the wiring input opening located on the rear of the dryer machine.   
     
     
         5 . The dryer machine according to  claim 1 , characterized in that:
 at least one normally-opened thermostat can be connected between two powered wire lines.   
     
     
         6 . The dryer machine according to  claim 1 , characterized in that:
 The electric charge comprises at least one motor and one electronic power source.   
     
     
         7 . The dryer machine according to  claim 1 , characterized in that:
 the time to completely de-energize the dryer machine is at most 1 minute.   
     
     
         8 . The dryer machine according to  claim 1 , characterized in that:
 the time to de-energize the dryer machine is 1 minute or less.   
     
     
         9 . The dryer machine according to  claim 1 , characterized in that
 the switches, as part of the electrical facility, are switches preferably of a ceramics type with a working capability of at least 30 amperes.