Patent Publication Number: US-2021180241-A1

Title: Steam iron for clothes

Description:
FIELD OF THE INVENTION 
     The invention relates to technical and functional enhancements applied to a heating set defining a steam chamber and a surface for ironing fabrics. The heating set is typically used in steam irons. 
     BACKGROUND OF THE INVENTION 
     Typically, electric irons are devices with a base heated by a resistor (also known as an electric resistor) that is supported by a case made of plastic, metal or other thermoplastic material, having a handle at the top of the case to support the operator&#39;s hand, which performs continuous movements over the surface to be smoothed or ironed. 
     Various models have additional elements, such as a temperature controller and an internal chamber for steam production, with a steam escape valve to humidify the fabric being smoothed or ironed. 
     Currently, there is a considerable variety of steam irons, as taught by the following documents: U.S. Pat. Nos. 4,835,363, 5,146,700, 6,018,897, 6,144,014, 9,376,768, 9,540,760, U.S. Ser. Nos. 10/053,814, 10/309,053, 10/351,992 and 10/358,764. These documents are mentioned herein just as examples to highlight a particularity of the known assembly techniques for steam and heating chambers, wherein the electric resistor is typically assembled inside the plate configuring the steam chamber. 
     Traditionally, the heating set of a steam iron is usually formed by two metal plates, preferably made of aluminum, including an upper plate defined as a heating body and a lower plate defined as a flat ironing base. 
     Usually, the heating body has an upper side with a specific configuration that forms two basic portions, one being the housing for a shielded resistor and the other one being the steam chamber provided with water from a reservoir by a pump or a dripping valve. Said steam chamber is defined by protruding walls that guide produced steam according to a desired route. Said route has a series of vertical holes for passing the steam underneath the heating body, which attaches to one side of the flat ironing base. The other side of the flat ironing base has other holes and other features to distribute the steam over the fabric to be ironed. 
     Therefore, a predominant form of assembly for the electric resistor is directly over the heating body and around the steam chamber, which is not advantageous since the transference of heat should occur between the heating body and the flat ironing base. In the traditional configuration, the heat transfer significantly decreases by the time the steam generated in the heating body reaches the flat ironing base. 
     SUMMARY OF THE INVENTION 
     In one embodiment of the invention, the heating body and the flat ironing base are specifically arranged so that one single heating plate is located in between the heating body and the flat ironing base. The heating plate uses metal sintered ceramic resistors, also known as a metal ceramic heater (MCH), as a heat generating source. 
     Therefore, the invention relates to various changes in the arrangement of the heating body and the flat ironing base so that one single heating plate is placed between them, the heating plate embedding electric resistors made of metal sintered ceramic as a substitute for conventional shielded electric resistors. 
     The heating plate is placed and stabilized with thermal paste between the heating body and the flat ironing base, allowing for quick and complete heat transference between the thermal ceramic element and the blade contacting the fabric to be ironed. 
     The heating plate with ceramic resistors is connected to the electrical power by a power cord that is connected to the main power supply, and includes the respective temperature control devices. 
     The use of sintered metal ceramic resistors as a plate directly applied to the blade that contacts the fabric to be smoothed allows for quick and uniform heat transference, thermal stability, self-control of the maximum temperature reached and about an 80% reduction in energy consumption compared to conventional systems. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a schematic side view of a steam iron; 
         FIG. 2  shows a perspective upper angle view of an assembled heating set; 
         FIG. 3  shows a perspective lower angle view of the assembled heating set; 
         FIG. 4  is an exploded perspective view of the heating set from an upper angle; 
         FIG. 5  shows another exploded perspective view of the heating set from a lower angle; 
         FIG. 6  shows a longitudinal cut view of the heating set of  FIG. 2 ; and 
         FIG. 7  is a cross-sectional cut view of the heating set of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In one embodiment of the invention, as shown in  FIG. 1 , the steam iron for clothes comprises a heating set ( 1 ) supported on an upper side of the set ( 1 ) by a case ( 2 ) made of metal or another thermoplastic material, with a handle ( 3 ) on a top of the case ( 2 ) to support the operator&#39;s hand, which performs continuous movements over the surface to be ironed. 
     The case ( 2 ) has a rear support plane ( 4 ) for resting the steam iron when the iron is not in use. 
     The case ( 2 ) embeds a reservoir provided with a re-load opening ( 5 ) and comprises a cord ( 6 ) to provide electricity to the iron by means of a 110 or 220 V main supply. 
     The case ( 2 ) also includes a traditional power supply regulated by a typical thermostat ( 7 ). 
     Other elements that usually form part of the iron are not shown. 
       FIGS. 2 and 3  show the heating set ( 1 ) fully assembled, comprising three overlapped portions: an intermediate portion defined as a heating body ( 8 ), an upper plate ( 9 ) for hermetic closing and a lower ironing plate ( 10 ). 
     Turning to  FIGS. 4, 5, 6 and 7 , the heating body ( 8 ) has, on an upper face, a steam chamber ( 11 ) provided with water from a reservoir by a pump or dripping valve (not shown). The steam chamber is defined by a labyrinth of protruding walls ( 12 ) that guide the steam as the steam is produced according to a desired route ( 13 ). The route has a series of vertical holes ( 14 ) for passing the steam underneath the heating body ( 8 ) which attaches to a first side of the flat ironing plate ( 10 ). The other side of the flat ironing plate ( 10 ) has corresponding holes ( 15 ) that align with the series of vertical holes ( 14 ) to release steam over the fabric to be ironed. 
     The upper face of the heating body ( 8 ) includes a plurality of projections ( 16 ) for fixing the hermetic plate ( 9 ) and also for fixing the case ( 2 ) and other parts of the iron. 
     A lower face of the heating body ( 8 ) is defined by a first U-shaped plane ( 17 ) along which the vertical holes ( 14 ) are distributed. 
     The first U-shaped plane ( 17 ) configures a second recessed plane ( 18 ), both of which are adjusted over an upper internal plane ( 19 ) of the ironing plate ( 10 ). There is sufficient space between the lower face of the heating body ( 8 ) and the upper internal plane ( 19 ) to receive a heat generating set defined by a heating plate ( 20 ) of metal sintered ceramic resistors, which is stabilized with an appropriate quantity of thermal paste (not shown). 
     The heating plate ( 20 ) with the metal sintered ceramic resistors is sufficiently thick enough to be housed in between and remain in contact with the second recessed plane ( 18 ) of the heating body ( 8 ) and the upper internal plane ( 19 ) of the ironing plate ( 10 ). 
     The heating plate ( 20 ) with metal sintered ceramic resistors is connected to the thermostat ( 7 ) to receive electrical power by means of the power cord ( 6 ) that connects to the main power supply. 
     The heating plate ( 20 ) for ceramic resistors is directly applied between the heating body ( 8 ) and the ironing plate ( 10 ), considerably increasing heat transference efficiency. Such efficiency is significant both for steam generation, and for the ironing surface defined by the ironing plate ( 10 ). 
     The use of plate-shaped ceramic resistors is also advantageous for quick and uniform heat transference, ensuring thermal stability and self-control of the maximum temperature reached, and allowing for about an 80% reduction in power consumption. 
     Considering the above, the main innovation of the invention lies in the form of assembly of the heating set, which is made by direct contact between the heat generating set connected to the power supply and the flat ironing base. This form of construction also allows the novel use of metal sintered ceramic as a heat generating source for this kind of application.