Abstract:
The present invention discloses a steam generating device comprising a control circuit for monitoring the temperature and controlling water filling and heating and steam discharging, and a sealed container which is highly temperature resistant. An electric heating tube is mounted in the container and a temperature sensor is mounted on the outer surface of the container. The electric heating tube and the temperature sensor are connected respectively to the control circuit. On the top of the container there is installed a four-way electromagnetic valve, and on the wall of the four-way electromagnetic valve there is installed a water intake tube connected to a water supply. A steam iron using the steam generating device is also disclosed in the present invention, wherein the steam iron can be used together with the steam generating device and has the virtue of continuous water filling steam generation.

Description:
FIELD OF THE INVENTION 
   The present invention generally relates to steam generating devices. In particular, the present invention relates to steam generating devices for use with associated irons. 
   BACKGROUND OF THE INVENTION 
   Typically, steam irons that are used in residential households, clothing stores, and/or clothing factories can be categorized into three types. The first type includes irons having a small water container and which cannot produce vertically continuous steam. The second type includes irons suitable for use in households and which has an embedded water container. This second type of iron can only be used for a limited period of time, after which time the water container must be filled. The water container cannot be filled while the iron is in operation. This limited operation time is not convenient and steam cannot be supplied immediately and thus, is inefficient. 
   The third type of irons include those suitable for use in clothing factories. This third type of iron includes two parts: a steam generating device and an iron or spray gun for ironing clothes. The steam generating device is typically a boiler which is used to generate a continuous supply of steam that is directed to the iron or spray gun via a tube for ironing clothes. However, these types of irons are only suitable for use in large-scale clothing factories since they are prohibitively costly and inconvenient for use in residential households due to their large size and heavy components. 
   Conventionally, a steam generating device and iron that is low in cost and suitable for use in large and medium-sized households and small-sized clothing stores or clothing factories does not exist. 
   SUMMARY OF THE INVENTION 
   Briefly stated, a steam generating device of the present invention in a preferred form comprises a control circuit for monitoring temperature, controlling water filling, and generating steam. The steam generating device has a sealed container which is constructed of a high temperature resistant material. An electric heating tube is mounted within the container and a temperature sensor is mounted on the outer surface of the container. The electric heating tube and the temperature sensor are each connected to the control circuit. On the top of the container there is installed a four-way electromagnetic valve on the wall of which there is installed a water intake tube connected to a water supply. The four-way electromagnetic valve is connected to the control circuit. 
   The ends of the electric heating tube may be directly welded to the inner wall of the container and extend outside of the container. 
   The electromagnetic valve includes a steam intake. The steam intake is connected to three steam outlets. Spring elements and a rubber plug capable of withstanding pressure are mounted to each of two steam outlets of the three steam outlets. The spring elements and rubber plugs form a pressure release valve on one steam outlet and an overflow valve on the other steam outlet. 
   A middle portion of the electric heating tube may be attached by welding to the inner wall of the container. The temperature sensor may be mounted on the outer surface of the container at a point corresponding to the position of the welding on the other side of the wall. 
   The steam iron system in the present invention may comprise a steam generating device, a control circuit and an iron connected to the steam generating device. The steam generating device includes a sealed container which is constructed of a high temperature resistant material. An electric heating tube is mounted within the container and a temperature sensor is mounted on the outer surface of the container. The electric heating tube and the temperature sensor are each connected to the control circuit. On the top of the container there is installed a four-way electromagnetic valve on the wall of which there is installed a water intake tube connected to a water supply. The four-way electromagnetic valve is connected to the control circuit. 
   The iron may be a steam iron which includes a base plate, an upper housing, and a steam regulating device between the upper housing and the base plate. Both an ordinary steam outlet and a strengthened steam outlet are located on the base plate. Both the ordinary steam outlet and the strengthened steam outlet are connected to the steam regulating device. The steam regulating device is connected to one of the three steam outlets of the four-way valve. 
   The steam regulating device is provided with a steam intake connected to the four-way valve. The steam regulating device also includes an ordinary steam outlet and a strengthened steam outlet which are respectively connected to the ordinary steam outlet and the strengthened steam outlet mounted on the base plate. The steam intake of the steam regulating device is connected to both of the ordinary steam outlet and the strengthened steam outlet. Located between the ordinary steam outlet, the strengthened steam outlet, and the steam intake is a pushdown regulating rod. The pushdown regulating rod includes a spring element for the restoration of the pushdown regulating rod after being pushed down. 
   An object of the present invention is to provide a steam generating device that is simple in structure, low in cost, and capable of providing steam continuously and fully. 
   Another object of the present invention is to overcome the defect of discontinuous steam production as commonly found in conventional irons. 
   A further objective of the present invention is to provide a steam iron when used with a steam generating device which allows clothes to be ironed continuously with the iron needing substantially no time for an operating condition to be reached. Thus, the iron can be operated efficiently such that it substantially replicates the capacity of a boiler with respect to steam generation. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic view showing a steam iron consistent with the present invention that is discharging ordinary steam; 
       FIG. 2  is a schematic view showing a steam iron consistent with the present invention that is discharging strengthened steam; 
       FIG. 3  is a schematic view showing a steam iron consistent with the present invention that is directing steam to a water container; 
       FIG. 4  is a side view of a four-way electromagnetic valve consistent with the present invention; 
       FIG. 5  is a schematic diagram of the four-way electromagnetic valve of the present invention; 
       FIG. 6  is a schematic diagram of a steam generating device showing the structure of a welding point of an electric heating tube and an inner wall of a container consistent with the present invention; 
       FIG. 6A  is an enlarged view of  FIG. 6  showing the structure of the welding point of the electric heating tube and the inner wall of the container; 
       FIG. 7  is a side perspective view of a steam regulating device consistent with the present invention; 
       FIG. 8  is a schematic diagram of the steam regulating device consistent with the present invention; 
       FIG. 9  is an elevated perspective view from the rear quarter of a steam regulating device in association with a base plate consistent with the present invention; 
       FIG. 10  is a view from below of a base plate consistent with the present invention; 
       FIG. 11  is a schematic diagram of the control circuit consistent with the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The detailed description of the preferred embodiment of the present invention shall be described hereinafter with reference to the drawings wherein like numerals represent like parts throughout the views. 
   In one embodiment of the invention, as shown in  FIGS. 1 to 3 , the steam iron system in the present invention includes a steam generating device  9  and a steam iron  14 . The steam generating device  9  and the steam iron  14  are connected by a tube  15  attached to a four-way electromagnetic valve  12 . The steam generating device  9  is connected to a cold water container  1  via a second tube  16 . The second tube  16  may be connected to a pump  4  such that the pump is intermediate the ends of the second tube  16 . A float valve  2  is installed inside the cold water container  1 . Located underneath the float valve  2  is a magnetic switch  3 . It should be noted that in one embodiment of the invention, the cold water container  1  can be replaced by a water pipe and the float valve  2  and the magnetic switch can be replaced by other control devices to regulate water flow. 
   As shown in  FIGS. 1-3  and  6 , the steam generating device  9  includes a sealed container  90  which is constructed of high temperature resistant material. An electric heating tube  8  is mounted within the container  90 . The connection end  80  of the electric heating tube  8  extends outside of the container  90  and may be welded to the wall of the container  90 . The middle portion of the electric heating tube  8  may also be welded to the wall of the container  90 . As shown in  FIGS. 6 and 6A , a temperature sensor  7  may be mounted at the location on the outer surface which corresponds to the location adjacent to where the heating tube  8  is welded on the outer surface of the container  90 . The temperature sensor  7  and the electric heating tube  8  are connected to the control circuit of a printed circuit board (PCB)  5  via, for example, wires. The operation of the control circuit is responsive to signals from the temperature sensor  7 . 
   In one embodiment of the present invention, the temperature within the device is monitored with a temperature sensor  7  mounted on the outer surface of the device. The temperature sensor  7  generates signals and transmits the signals to the PCB  5  which controls both the operation of the heating tube  8  and the pump  4  inside the steam generating device. When the temperature in the inner part of the steam generating device rises to a preset value, the pump  4  starts to pump water. When the temperature drops below a preset value, due to such things as cold water being added to the device, the pump  4  stops pumping. This regulation of circulation allows the temperature of the steam generating device to be kept within a desired range, for example, at a range where steam is generated continuously. When the water level in the water container reaches a preset low level, a magnetic switch  3  is activated and an indicator is triggered. For example, the control power supply in the PCB  5  may flash an indicator. At the same time, the control circuit of the steam generating device may stop energizing the heating element  8 . 
   As shown in  FIG. 6 , on the side wall of the container  90  there is a water intake  10  which is connected to the second tube  16 . Water can be added to the container  90  under the control of the control circuit which controls the pump  4 . On top of the container  90  there is a steam outlet  91  to which a four-way electromagnetic valve  12  is associated. 
   In one embodiment of the present invention, as shown in  FIGS. 1 and 2 , the steam iron  14  includes a base plate  140 , an upper housing and a steam regulating device  13  between the upper housing and the base plate  140 . On the base plate  140  there is an ordinary steam outlet  143  and a strengthened steam outlet  144  (shown in  FIG. 10 ). As shown in  FIGS. 8 and 9 , the steam regulating device  13  has a steam intake  130  which is connected to the tube  15 , an ordinary steam outlet  131 , and a strengthened steam outlet  132 . The ordinary steam outlet  131  and the strengthened steam outlet  132  are respectively connected to the ordinary steam outlet  143  and the strengthened steam outlet  144  on the base plate  140  (shown in  FIG. 10 ). As shown in  FIGS. 7 and 9 , the steam intake  130  of the steam regulating device  13  is connected to both the ordinary steam outlet  131  and the strengthened steam outlet  132 . 
   In one embodiment of the present invention, A regulating device may be associated with the ordinary steam outlet  131 , the strengthened steam outlet  132 , and the steam intake  130 . The regulating device, as shown in  FIG. 8 , may include a pushdown regulating rod  133  and a spring element  134  for the positional restoration of the regulating rod  133  to its normal position. When the regulating rod  133  is at its normal position, the steam intake  130  is connected to both the ordinary steam outlet  131  and the strengthened steam outlet  132 . When the regulating rod  133  is pushed down, the steam intake  130  is connected only to the strengthened steam outlet  132 . 
   As shown in  FIGS. 4 and 5 , the four-way electromagnetic valve  12  may include a steam intake  120  and three steam outlets  121 ,  122  and  123 . The steam intake  120 , in one embodiment of the invention, is connected to the steam outlet  121 . As shown in  FIG. 5 , positioned inside the steam outlet  121  is a silicon rubber plug  124  and spring element  125 . Under normal operating conditions, the silicon rubber plug  124  does not seal the steam outlet  121 . Under certain pressure conditions, the silicon rubber plug  124  seals the steam outlet  121  and together they form an overflow valve (shown in  FIG. 3 ). Inside the steam outlet  122  there is also a silicon rubber plug  126  and a spring element (not shown) that form a release valve. Under normal conditions, the silicon rubber plug  126  seals the steam outlet  122  and is opened when the pressure of steam reaches a certain value. The opening and closing between the steam outlet  123  and the steam intake  120  is controlled by an electromagnetic valve. 
   In one embodiment of the present invention, the normal operation of a steam iron is shown in  FIG. 1 . When the cold water container  1  is filled with water, the float valve  2  activates the magnetic switch  3 . The PCB  5  then controls the device. For example, the water pump  4 , controlled by PCB  5 , begins to pump water through the second tube  16  into the container  90 . The PCB  5  then operates to cause the electric heating tube  8  in the container  90  to be energized. 
   In one embodiment of the invention, the operation of the pump  4  is controlled by the PCB  5  with a change of resistance. The operation of the pump  4  may allow for a continuous circulation wherein the pressure in the container  90  is less than, for example, 0.2 bar. Steam generated in the container  90  by heating tube  8  is discharged through the outlet  91  and into the steam intake  120  of the four-way electromagnetic valve  12 . The steam is then discharged through the steam outlet  121 . 
   In one embodiment of the present invention, air in the container  90  is discharged to ensure, when the iron is in a cold condition, that outer air pressure and air pressure inside the container are balanced in order to prevent air pressure caused by change of the steam generating device from a cold state to a hot state due to the cold water being pumped into the steam generating device by the water pump during a preheating of the device. When the preheating time reaches, for example, 2 minutes and 30 seconds (a time value preset in the PCB  5 ) the steam is discharged out the iron  14 . It should be understood that the other time values can be preset in the PCB and that the pressure in the container  90  may be, for example, more than or less than 0.2 bar. 
   The silicon rubber plug  124 , in one embodiment of the invention, seals the steam outlet  121  with the aid of the spring element, the steam outlet  123  is opened and steam is discharged from the container  90  and conveyed to the steam intake  130  of the steam regulating device  13  of the steam iron  14  through the tube  15 , then the steam is conveyed to the steam outlet of the base plate  140  of the iron through strengthened steam outlet  132  and ordinary steam outlet  131 , as shown in  FIG. 1 . In this configuration, ordinary steam and strengthened steam is generated. When the regulating rod  133  of the steam regulating device  13  is at a normal up position, the steam comes out from the strengthened steam outlet  132  and the ordinary steam outlet  131 . When the regulating rod  133  is pushed down, the ordinary steam outlet  131  is sealed and, as shown in  FIG. 2 , the steam comes out from only the strengthened steam outlet  132 . 
   As shown in  FIG. 3 , when the pressure in the container  90  reaches, for example, about 5 bars, the steam outlet  122  in the four-way valve  12  on the top of the container  90  is opened and high-pressure steam is released and is directed to, for example, the cold water container  1  through a water pipe connected to the steam outlet  122 . 
   In one embodiment of the present invention, the operation of the steam iron of the present invention is divided into two stages, stage 1 and stage 2. 
   Stage 1 is the period of time before the steam comes out of the device when, for example, as shown in  FIG. 11 , the voltage of the 10th leg of an integrated (IC) module  1 , for example a Type-LM324 integrated module, is about 15 V, the voltage of the 5 th  leg of the integrated module IC shall be induced to about 12.25 V. When the temperature of the container  90  rises, for example, to about 143°, there is a decrease of the resistance of the temperature sensor  7 , and the voltage of the 6 th  leg of the integrated module IC  1  is induced to be more than 12.25 V of the 5th foot of the integrated module IC  1 . The 7 th  leg of the integrated module IC  1  is then reversed to a low level and the electric tube  8  in the container  90  is no longer energized. When the temperature of the container  90  falls, for example, to about 131° from about 143°, the resistance of the temperature sensor  7  rises as there is a decrease of the temperature. The voltage of the 6 th  leg of the integrated module IC  1  is then induced to be less than 12.25 V of the 5 th  foot of the integrated module IC. The 7 th  foot of the integrated module IC is then reversed to a high level and the electric tube  8  in the container  90  is energized. In such a circulation, the pressure in the container  90  is kept between about 1.8 to about 3.2 bars. 
   In one embodiment of the present invention, the PCB  5  is provided with another integrated circuit, for example a Type-4001 integrated circuit, which functions as the protection of the preheating delay. In one embodiment of the present invention, the temperature rise of the container  90  can be sustained for about 2 minutes and 30 seconds from the cold state, and since only the temperature of the container  90  must be increased from the cold state and sustained, the four-way electromagnetic  12  is activated. For example, when the pressure of the steam in the container  90  exceeds 5 bars, the release valve of the four-way electromagnetic  12  starts to operate to release the high-pressure steam in the container  90 . 
   Stage 2, in one embodiment of the invention, is the stage of steam discharge after, for example, a preheating of 2 minutes and 30 seconds, when steam is discharged from the device. For example, when the voltage of the 10 th  leg of the integrated (IC) module  1  is, for example, about 20 V, the voltage of the 5 th  leg of the IC module  1  is induced to about 15.20 V. When the temperature of the container  90  is increased to about 160° by the electric heating tube  8 , the water pump  4  begins to pump water. At a point when the temperature of the container  90  is decreased to about 145°, the water pump  4  stops pumping under the control of the IC module  1 . However, since the water pumped into the container  90  is cold, the temperature of the container  90  may be decreased further to about 134°. At this lower temperature, the temperature is increased with the heating tube  8  under control of the IC module  1 . During the whole process of steam discharge, the electric heating tube  8  stops heating for 3 to 4 seconds only when the temperature is at the highest set temperature, for example, about 160°. When the temperature is lower than, for example, about 160°, the heating tube  8  starts to heat immediately to ensure that there is steam in the container  90  during the whole process. 
   In one embodiment of the present invention, the steam generating device in the present invention can generate continuously steam in a certain range of temperature and also, the steam generating device can be used together with steam irons and spray guns. During the whole process of ironing, water can be filled in and steam can be generated continuously. 
   Moreover, the installation of the release valve and the overflow valve in the four-way electromagnetic valve may ensure the safety in operation. 
   While certain embodiments of the foregoing invention have been set forth for the purposes of illustration, the foregoing description should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations and alternatives may occur to one of skill in the relevant art without departing from the spirit and scope of the present invention.