STEAM CLEANER AND STEAM IRON APPARATUS
A combination steam cleaner and steam iron includes a steam generator, a steam cleaner and a steam iron. The steam generator includes a control device connected to a boiler element for boiling water to produce steam. The steam iron includes an iron heating element and a thermostat. The steam generator receives a maximum amount of power except when the iron thermostat is closed and the iron heating element requires power; the amount of power delivered to the boiler element is then reduced. The control device includes a circuit configured to deliver electrical power to the boiler element with a preset duty cycle, so that the reduced amount of power is a fraction of the maximum power in accordance with the duty cycle.
The present invention relates to steam cleaners and steam irons and, more particularly, to an improved steam cleaner and steam iron apparatus.
BACKGROUND OF THE INVENTIONSteam cleaning appliances require a substantial amount of power to operate properly. Typically, steam cleaning appliances require around 1500 watts of power (1800 watts maximum) to sufficiently heat stored water to provide the necessary steam for the cleaning appliance.
Similarly, steam generating irons require a substantial amount of power to operate properly. Steam generating irons generally include two heating elements, one to heat the iron and the other to heat water to produce steam. In the United States, the combined amount of electrical power utilized by both heating elements, for practical purposes, exceed 1800 watts due to UL regulations limiting voltage levels to 120 volts, with a maximum draw of 15 amps at this voltage level. A combined steam cleaner and steam iron includes a base unit (having a boiler tank, heating element, power switch and safety devices) with both a detachable steam cleaner accessory and a steam iron accessory; only one of the accessories may be used at one time. The combined wattage of the base and the iron may not exceed 1800 watts.
Given these power constraints, a device that combines a steam cleaner with a steam iron would not be able to draw sufficient power to power the separate heating elements of the combined device. One attempt to overcome this problem is disclosed in European Patent No. EP 0 809 728 B1. The design shown therein is intended for use in Europe, which generally has line voltage of 220 volts and power standards suitably high that provide sufficient power to a device that includes both a steam cleaner and a steam iron.
A combined steam cleaner and steam iron apparatus which overcomes the problem of power constraint in the U.S. is described in commonly owned U.S. Pat. No. 6,711,840, incorporated by reference herein. However, the apparatus described in the '840 patent requires two separate heating elements for the boiler. There remains a need for a combined steam cleaner and steam iron with a reduced number of components necessary to perform the desired function (that is, a single boiler heating element), thus reducing the cost of the combined unit.
It therefore is desirable to provide a simple, low cost, combined steam cleaner and steam iron apparatus designed to properly operate under restricted power requirements. In particular, it is desirable that the apparatus be able to regulate the power drawn by the boiler under various conditions, such as when heating the iron.
SUMMARY OF THE INVENTIONThe present invention addresses the above-described need by providing a combination steam cleaner and steam iron that includes a steam generator, a steam cleaner and a steam iron. The steam generator includes a control device connected to a boiler element for boiling water to produce steam. The steam iron includes an iron heating element and a thermostat. The steam generator receives a maximum amount of power except when the iron thermostat is closed and the iron heating element requires power; the amount of power delivered to the boiler element is then reduced. The control device may include a circuit configured to deliver electrical power to the boiler element with a preset duty cycle, so that the reduced amount of power is a fraction of the maximum power in accordance with the duty cycle.
The control device may include a half-wave rectifier for delivering electrical power to the first heating element with a 50% duty cycle, so that the reduced amount of electrical power is 50% of the maximum amount. The control device may further include a relay energized in accordance with the iron thermostat being in the closed state, the relay thereby coupling the half-wave rectifier to the boiler heating element.
The control device may also include a gated conductor device and a timer device, where the gated conductor device is configured to conduct current in accordance with a signal at the gate from the timer device. The duty cycle is preset in accordance with values of resistances coupled to the timer device.
The boiler element is preferably a 1500 watt (up to 1800 Watt) heater and the iron heating element is preferably a 600 watt heater. About 1500 watts of power are drawn during use of the steam cleaner and about 1500 watts of power are drawn during use of the steam generator and the steam iron.
For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numbers indicate like features and wherein:
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
The steam generator includes a pressostat, a thermostat, and/or a thermofuse serially coupled to the boiler heating element. The steam generator also includes a top surface designed for use as a resting surface on which either the steam cleaner or the steam iron may be mounted. The top surface is designed to support a heated steam iron.
Boiler unit 10 receives electrical power via a power cable 16 that is connected to a suitable power receptacle during operation of the apparatus of the invention. Boiler unit 10 includes within its housing 14 a main on/off switch (with on/off light) 15 and also includes a heating element 18 with electrical connections thereto, shown in
Referring back to
Referring to
In order to conform to the wattage constraints discussed above, the electrical current delivered to (and hence the power drawn by) heating element 18 is regulated according to the state of the thermostats (that is, on/off or heat/no heat) of the boiler unit and the steam iron unit. Various circuits and arrangements for regulating the power drawn by the boiler are described in more detail below.
Three-Pole Iron Unit Thermostat with Limiting CircuitSocket 12 has five electrical contacts, A-D and ground, and a steam hose connection E. The switched output from main on/off switch 15 is supplied to contact B of the steam generator unit's socket 12, and contact A of socket 12 is connected to the neutral terminal of power cable 16. Contact C connects between control device 70 and boiler element 18. The supply line to boiler element 18 is connected to safety devices 54 and 56 mentioned above. As further discussed below, power supplied to contact B is routed back through contact C and then to boiler element 18 when the steam cleaner 30 is in use. When the steam iron is in use, power supplied to contact B is supplied to an iron element heater 25 disposed within the steam iron 20, wherein iron heating element's 25 supply line is connected in series through a safety device (thermal cutoff 21) and three-contact thermostat 23 to be explained in detail hereinafter. The operation of a thermal cutoff is well known in the art and thus further description is not provided herein.
Neutral terminal N is connected to steam release valve 50, as previously mentioned, and the valve's supply line is coupled to contact D of socket 12. Contact A of socket 12 is coupled to the neutral line. Both steam iron 20 and steam cleaner 30 include respective on/off switches 28 and 36. When either the steam iron or the steam cleaner is connected to boiler unit 10 (via their respective plugs 24 and 34), switching the steam on/off switch 28 or 36 of the attached device (steam iron 20 or steam cleaner 30) to the “on” position completes the circuit through steam release valve 50, thus causing steam to be released from boiler unit 10 via hose connection E (also called the steam output port) within socket 12 through the particular hose attached (22 or 32), and then to the particular device in use (steam iron 20 or steam cleaner 30). As can be seen in
The steam iron 20 contains an electrical circuit as shown in
The steam cleaner 30 also contains an electrical circuit as shown in
The operation of the invention when the steam iron is attached to the steam generating unit will now be described. The steam iron's plug 24 is attached to the steam generator's socket 12, so that the output of steam release valve 50 is supplied to steam iron hose 22, the switched power output from main on/off switch 15 is supplied to iron heating element 25 within the steam iron 20, and steam release valve/solenoid 50 is controlled by steam on/off switch 28 within the steam iron 20. The boiler unit 10 is filled with water in a manner well known in the art, and the main on/off switch 15 is manually set to “ON” to power both boiler element 18 within the boiler 10 and to power iron element heater 25 within the steam iron 20. When the temperature of the iron is beneath the predetermined temperature threshold of the iron, the switch of iron thermostat 23 is initially in the normally closed “NC” contact position. As a result, contact C′ is effectively left open. Since contact C′ is left open, control device 70 is connected in series with boiler element 18. The amount of power that boiler element 18 is enabled to provide is the maximum power (1500 watts up to 1800 watts), regulated by the limiting circuit of the control device 70. The factor by which the boiler power is regulated is dependent upon the design of the limiting circuit (not shown). With the given constraint of 1800 watts, this factor must be less than or equal to approximately 70% in order for the iron to be supplied with 600 watts while the boiler is simultaneously supplied 1100 watts. The boiler 10 and the steam iron 20 then collectively draw less than 15 amps of current (at 120 volts). During this time, steam on/off switch 28 on the steam iron is kept in the “off” position. Boiler element 18 causes the water in the boiler tank to boil to produce steam, and iron heating element 25 heats the bottom surface of the steam iron 20. Upon sufficient heating of steam iron 20 by iron element heater 21, ironing is carried out in a manner well known in the art. Likewise, steam produced within boiler 10 is supplied through the steam iron upon switching steam on/off switch 28 to its “on” position (or depression of a button or other suitable on/off device). As previously mentioned, during use of steam iron 20, the steam iron may be conveniently placed on the top surface 19 of the steam generator. Upon completion of steam ironing, both main on/off switch 15 and steam on/off switch 28 are set to the “off” position and plug 24 is removed from the steam generator's socket 12.
Iron heating element's 25 supply line is connected in series through a safety device (thermofuse or thermal cutoff) 21. Iron thermostat 23 includes three contacts: common “COM”, normally closed “NC”, and normally open “NO”. Initially, when the iron is below a predetermined temperature designated for a threshold of the thermostat 23, the state of the thermostat is such that common contact “COM” is connected to the normally closed contact “NC”. After the iron reaches the predetermined temperature of the thermostat, the thermostat state shifts so that the contact “COM” is connected to the normally open contact “NO”. At this point, voltage is supplied to contact C′. As a result, the iron heating element 25 does not receive the previously supplied voltage which was applied to the normally closed contact “NC” before the threshold temperature was reached. Thus, the iron 20 does not heat. In the alternative, power supplied from contact B′ is supplied directly to contact C′ and C; thereby, delivering the full amount of power supplied by the line terminal of power cable 16 to the boiler element 18.
To utilize the steam cleaner 30, the steam cleaner's plug 34 is attached to socket 12 of the steam generator. As previously mentioned, such connection provides the switched power (output from main on/off switch 15) to boiler element 18 alone, where the control device 70 is bypassed since contacts B″ and C″ are electrically connected. The effect of bypassing the control device 70 is that boiler element 18 draws the maximum power of 1500-1800 watts for boiling the water to generate steam. The output of steam release valve 50 is supplied to steam cleaner hose 32, and steam release valve 50 is controlled by steam on/off switch 36 within the steam cleaner 30. The tank in boiler 10 is filled with water and the main on/off switch 15 is set to its “on” position, to power boiler element 18 at the maximum power of 1500 to 1800 watts. Boiler element 18 thus draws less than 15 amps of current (at 120 volts). Steam on/off switch 36 on the steam cleaner is initially kept off. Steam cleaning then is performed by turning steam on/off switch 36 to its “on” position, to supply the steam through the steam cleaner hose 32 and out through nozzle 38. Upon completion of steam cleaning, both switches 15 and 36 are turned off and the connectors are detached.
As can be appreciated from the foregoing discussion and designs shown in
When the iron thermostat 27 is open (that is, the iron is at the required temperature and is not calling for heat), no current is present in either heating element 25 or in the coil of relay 58. Contact 58-1 then remains closed, and full power may be drawn by the boiler whenever thermostat 54 is closed. However, when iron thermostat 27 is closed, heating element 25 is connected to the line terminal and relay 58 is energized. This causes relay contact 58-1 to open and contact 58-2 to close, which in turn causes half-rectified current to be delivered to boiler thermostat 54 and boiler heating element 18. Accordingly, when the iron unit calls for heat, full power is delivered to iron heating element 25, while power delivery to boiler heating element 18 (when boiler thermostat 54 is closed) is reduced to a 50% duty cycle.
This arrangement allows for the iron unit to have priority in receiving heating current while permitting the boiler to receive maximum heating current when not required by the iron. This in turn provides improved system performance within the constraint of overall maximum power dissipation.
The solenoid of steam release valve 50 is connected to the line terminal and to steam release switch 28 of the iron unit (or steam release switch 34 of the steam cleaner unit 30) through connector 1. As in the previously described embodiment, steam is released from the steam iron via steam release valve 50 when steam release switch 28 is closed (thereby energizing the solenoid of steam release valve 50). Similarly, when steam cleaner 30 is connected to the boiler unit, steam is released when switch 36 is closed.
As in the embodiment of
When a 120 V source of power is supplied to the steam generator, the steam generator will draw less than 15 amps of current during use of the steam cleaner, and the steam generator and the steam iron collectively will draw less than 15 amps of current while both are in use.
It will be appreciated that a boiler, steam iron and steam cleaner as described in the above embodiments offer the advantages of high performance and efficiency with a simple and cost effective design.
All the features disclosed in this specification may be replaced by alternative features serving the same, equivalent or similar purpose, as will be understood by those skilled in the art. The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.
Claims
1. A steam iron, comprising:
- a steam generating unit including a first heating element, a first thermostat coupled to the first heating element, and a control device for controlling electrical power delivered to the first heating element; and
- a steam iron unit including a second heating element, and a second thermostat coupled to the second heating element,
- wherein
- the control device causes delivery to the first heating element of one of (1) a maximum amount of electrical power and (2) a reduced amount of electrical power less than the maximum amount, in accordance with a state of the second thermostat.
2. A steam iron according to claim 1, wherein
- the first thermostat is in one of (1) an open state in which the first heating element is not caused to generate heat and (2) a closed state in which the first heating element is caused to generate heat,
- the second thermostat is in one of (1) an open state in which the second heating element is not caused to generate heat and (2) a closed state in which the second heating element is caused to generate heat,
- the control device causes delivery of the maximum amount of electrical power to the first heating element in accordance with the first thermostat being in the closed state and the second thermostat being in the open state, and
- the control device causes delivery of the reduced amount of electrical power to the first heating element in accordance with the first thermostat being in the closed state and the second thermostat being in the closed state.
3. A steam iron according to claim 2, wherein the control device includes a half-wave rectifier for delivering electrical power to the first heating element with a 50% duty cycle, so that the reduced amount of electrical power is 50% of the maximum amount.
4. A steam iron according to claim 3, wherein the control device further includes a relay energized in accordance with the second thermostat being in the closed state, the relay thereby coupling the half-wave rectifier to the first heating element.
5. A steam iron according to claim 2, wherein the control device includes a circuit configured to deliver electrical power to the first heating element with a preset duty cycle, so that the reduced amount of power is a fraction of the maximum power in accordance with said duty cycle.
6. A steam iron according to claim 5, wherein the control device further includes a relay energized in accordance with the second thermostat being in the closed state, the relay thereby coupling said circuit to the first heating element.
7. A steam iron according to claim 5, wherein said circuit includes a gated conductor device.
8. A steam iron according to claim 7, wherein said circuit further includes a timer device, the gated conductor device is configured to conduct current in accordance with a signal at the gate thereof from the timer device, and the duty cycle is preset in accordance with values of resistances coupled to the timer device.
9. A steam iron according to claim 8, wherein said circuit further includes a DIP switch device for setting the values of the resistances.
10. A steam iron according to claim 8, wherein the resistances include a variable resistor.
11. A steam iron according to claim 1, wherein the steam generating unit has a single heating element.
12. A steam iron according to claim 1, wherein the maximum amount of electrical power is approximately 1800 watts.
13. A steam iron according to claim 1, further comprising a steam cleaner unit.
14. A combination steam cleaner and steam iron, comprising:
- a steam generating unit including a first heating element, a first thermostat coupled to the first heating element, and a control device for controlling electrical power delivered to the first heating element;
- a steam cleaner unit; and
- a steam iron unit including a second heating element, and a second thermostat coupled to the second heating element,
- wherein
- at most one of the steam cleaner unit and the steam iron unit is coupled to the steam generating unit, and
- upon coupling of the steam iron unit to the steam generating unit the control device causes delivery to the first heating element of one of (1) a maximum amount of electrical power and (2) a reduced amount of electrical power less than the maximum amount, in accordance with a state of the second thermostat.
15. A combination steam cleaner and steam iron according to claim 14, wherein
- the first thermostat is in one of (1) an open state in which the first heating element is not caused to generate heat and (2) a closed state in which the first heating element is caused to generate heat,
- the second thermostat is in one of (1) an open state in which the second heating element is not caused to generate heat and (2) a closed state in which the second heating element is caused to generate heat,
- the control device causes delivery of the maximum amount of electrical power to the first heating element in accordance with the first thermostat being in the closed state and the second thermostat being in the open state, and
- the control device causes delivery of the reduced amount of electrical power to the first heating element in accordance with the first thermostat being in the closed state and the second thermostat being in the closed state.
16. A combination steam cleaner and steam iron according to claim 14, wherein the steam generating unit has a single heating element.
17. A combination steam cleaner and steam iron according to claim 14, wherein the maximum amount of power is approximately 1800 watts.
18. A combination steam cleaner and steam iron according to claim 14, wherein the control device includes a circuit configured to deliver electrical power to the first heating element with a preset duty cycle, so that the reduced amount of power is a fraction of the maximum power in accordance with said duty cycle.
19. A combination steam cleaner and steam iron according to claim 14, wherein the control device includes a half-wave rectifier for delivering electrical power to the first heating element with a 50% duty cycle, so that the reduced amount of electrical power is 50% of the maximum amount.
20. A combination steam cleaner and steam iron according to claim 14, wherein so that upon coupling of the steam cleaner unit to the steam generating unit, closing of the first steam release switch causes release of steam via the steam release valve, and upon coupling of the steam iron unit to the steam generating unit, closing of the second steam release switch causes release of steam via the steam release valve.
- the steam generating unit further includes a steam release valve,
- the steam cleaner unit includes a first steam release switch, and
- the steam iron unit includes a second steam release switch,
Type: Application
Filed: Aug 10, 2006
Publication Date: Feb 14, 2008
Inventors: Maximilian Rosenzweig (Montreal), Brian R. McGee (Auburn, AL), Ognjen Vrdoljak (Laval)
Application Number: 11/463,774
International Classification: D06F 75/10 (20060101);