This application relates to a system of multiple linked appliances connected to a power supply through a single supply cord. In particular a refrigerator and microwave are connected for single plug operation while providing additional special purpose outlets.
Combination refrigerator and microwave oven systems are described in U.S. Pat. Nos. 4,880,954 and 4,847,722. In the devices described, the refrigerator is connected to the power supply and provides a connection for the microwave oven to be connected to the same supply. A single plug, therefore, serves to connect both appliances and the current required for each appliances is supplied by the same supply cord and circuit.
To make this combination attractive for use in dorm rooms, hotel rooms, recreational vehicles, tractor trailer cabs, and other similar locations, it is necessary to provide some means by which the peak currents of both appliances are not demanded from the supply at the same time. Many household circuits are protected from overload conditions by means of an automatic circuit breaker that is activated when current in the circuit exceeds the breaker rating. This is 15 amps in many circuits.
The duty cycle of a refrigerator used in these combined systems includes a current spike that occurs during the first few seconds of operation. This is the start up current for the refrigerator compressor and is considerably reduced, as the compressor obtains its operational speed. In typical refrigerator appliances the peak current may be in the range of 7 to 9 amps, while the steady state current may level off at 1.4 amps or less. A microwave oven demands a relatively steady 8 to 13 amps. It is apparent that an overload condition will occur frequently, when both appliances are in use, unless some control is exercised.
In the '954 patent the compressor power is disabled when the microwave is energized. This is accomplished by coupling the timer of the microwave to the compressor power. In addition a door interlock enables the compressor, since the microwave is disabled when the door is open. The '722 patent describes a control circuit for a combination microwave and refrigerator system in which a relay disables the microwave oven for a period of time depending on the rating of the compressor, when the compressor of the refrigerator is energized.
It would be advantageous to construct a combination microwave/refrigerator system, that also provides auxiliary outlets for low power applications, such as for the purpose of recharging cellular phones, operating lap top computers and other low power devices, while controlling the operation of the appliances to avoid overload conditions.
In an embodiment of this invention, a combination microwave and refrigerator system is constructed having a single plug input supply. The microwave oven is adapted to provide power to a refrigerator, and to auxiliary receptacles adapted for low power operation. The microwave oven includes a microprocessor controller adapted to monitor operation of the refrigerator compressor and controls the power to the microwave magnetron and other components. The current to the low power receptacles are separately monitored for control by the microwave controller. The microwave controller is adapted to balance the duty cycles of the connected appliances attached to avoid overload conditions. A control algorithm is implemented internally within the microwave controller. A receptacle for the refrigerator and the low power auxiliary receptacle may be implemented as part of the microwave control panel.
In one embodiment, the auxiliary outlets are constructed to provide low power for the purpose of recharging cellular phones, personal media devices, digital cameras, in addition to operating lap top computers and other low power devices. The current to the auxiliary outlets is sensed and provided to the microwave controller.
In another embodiment, the power to the auxiliary outlets is disabled by the microwave controller when the microwave magnetron is energized or whenever the current to the auxiliary outlets exceeds a preset value.
In one embodiment, a control model is established and executed by the microwave controller. The model is dependent on the state of operation of the microwave magnetron. As part of the control model, the power to the compressor is monitored to sense operation of the compressor. When power to the microwave is demanded, the compressor is disabled for a preset minimum period. When microwave demand ceases, refrigerator power is restored provided, that the preset minimum period has expired.
In another embodiment of the control module, sensing circuits are connected to monitor current to the auxiliary outlets. The control model is adapted to disable the power to the auxiliary receptacles, if the microwave is in operation. In addition the auxiliary receptacles are disabled if a predetermined maximum current is sensed. Another control model is based on operation of the refrigerator and operates to disable the auxiliary receptacles when the compressor is in the start up mode
In one aspect of the invention, a non-transitory processor storage readable medium having processor readable program code embodied therein for operating a control processor to control a system of multiple linked appliances having a microwave oven, a refrigerator, and a auxiliary power supply outlet is provided. The processor readable program code causes the control processor to disable the refrigerator and the auxiliary power supply outlet, when the microwave demands power, and enable the auxiliary power supply outlet when the microwave is off.
The system of this invention is explained in more detail below with reference to the accompanying drawing, in which:
A multiple linked appliance system 1, for example, a combination microwave oven 2, a refrigerator 3 incorporating features of the present invention is illustrated in the figures. Although the present invention will be described with reference to the embodiments shown in the drawings, it should be understood that the present invention may have many alternate forms. In addition, any suitable size, shape or type of elements or materials could be used. The computer operated devices described in this application may be constructed having one or several processors and one or several program product modules stored in one or several memory elements. For illustration, computer components may be described as individual units by function. It should be understood, that in some instances, these functional components may be combined.
One embodiment of a multi-appliance interconnected system 1 is illustrated in
Microprocessor 4 is the controller for the operation of the microwave oven 2 and is also adapted to control the other components of system 1, as shown in
Control panel 22 of microwave oven 2 may be adapted to provide a display of the particular status of the controlling relays, for example, LED's 13 and 14 may indicate that power to the outlets 11, and 12 are disabled or available. In one embodiment the lamps will light when power is available at the outlet and flash when disabled. A button operated touch panel provides manual control.
As shown in
In another embodiment, a clock device 21 could be used to provide timed delays during which, for example, refrigerator 3 would be prevented from undesirably rapid on/off cycles. When refrigerator 3 is disabled during microwave operation, a time delay of 3 minutes is provided during which refrigerator 3 will remain disabled, even if microwave use is only for a short period. Controller 4 may be programmed to manage the power to the components of the system to avoid overload conditions, while minimizing disruptions in the use of an individual appliance. A model of operative events and related control operations may be designed into the program executed by controller 4 to provide a control methodology as illustrated in
In one embodiment, as illustrated in the block diagram of
In one embodiment, shown in
In one embodiment, control models are established as shown in
In the embodiment shown in
In this embodiment, as shown in
A further embodiment of the processor operational model is shown in
In the embodiment of
In this manner a system of linked appliances, including a microwave oven, refrigerator, and a low power appliance may all be connected through a common supply cord without the risk of inconvenient interruptions in use caused by overloads.
It should be understood that the above description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art with out departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall with the scope of the appended claims.
This application claims priority from Provisional Application for Patent No. 61/009,419, filed Dec. 28, 2007.
Number | Name | Date | Kind |
---|---|---|---|
4763015 | St. Louis | Aug 1988 | A |
4847722 | Bennett | Jul 1989 | A |
4880954 | Bennett et al. | Nov 1989 | A |
5521359 | Bone | May 1996 | A |
20030075538 | Kish et al. | Apr 2003 | A1 |
20070086126 | Baxter | Apr 2007 | A1 |
20070262646 | Lee | Nov 2007 | A1 |
Number | Date | Country |
---|---|---|
2001-33043 | Feb 2001 | JP |
Entry |
---|
English translation Furukawa (JP2001-33043); Feb. 2001. |
Abstract Translation Furukawa et al. (JP2001-33043); Feb. 2001. |
Number | Date | Country | |
---|---|---|---|
20090188911 A1 | Jul 2009 | US |
Number | Date | Country | |
---|---|---|---|
61009419 | Dec 2007 | US |