Technical Background
This invention relates to defrosting systems wherein electrical energy is disbursed to defrost specific zones on an automobile or the like according to predetermined priorities.
Disclosure of the Invention
In accordance with the present invention, a controlled zone defrosting system is provided that selectively supplies electrical energy to defrosting devices formed of an electrically conductive glass coating material and located at specific areas on an automobile or the like.
One embodiment of the present invention contemplates a defrosting system that is responsive to preselected defrosting zone priorities.
Another embodiment contemplates a defrosting system that is responsive to sensed internal system conditions.
Yet another embodiment contemplates a defrosting system that is responsive to sensed ambient conditions.
Still another embodiment contemplates a defrosting system that may be powered by the battery of the associated automobile or by a separate electrical energy storage device.
Another embodiment of the present invention contemplates a defrosting system that may be powered by a photovoltaic device.
A further embodiment contemplates a defrosting system that may be powered by a photovoltaic device and an electrical energy storage device, which may be the battery of the associated automobile or a separate device.
Another embodiment contemplates a defrosting system that may be powered by a photovoltaic device and an electrical energy storage device such that at least part of the electrical energy generated by the photovoltaic device may be used to recharge the storage device.
Brief Description of the Drawings
In the drawings, in which like reference characters indicate corresponding parts in all the views:
FIG. 1 is a block diagram of an embodiment of the controlled zone defrosting system having a single source of electrical energy;
FIG. 2 is a block diagram of an embodiment of the defrosting system having more than one source of electrical energy; and
FIG. 3 is a block diagram of the control unit illustrated in FIG's. 1 and 2 .
Detailed Description of Preferred Embodiments of the Invention
With reference to FIG. 1, illustrated is a controlled zone defrosting system 10 having a control unit 12 shown connected to an electrical energy storage device, which may be a battery, 14 and also having a plurality of defrosting devices 16 to which the control unit disburses amounts of electrical energy according to preselected priorities. The defrosting devices 16 may be any of a number of well-known devices formed of an electrically conductive glass coating material the resistance of which transforms electrical energy into heat when an electrical current flows therethrough, the heat in turn acting to melt any ice formed on glass bearing the coating material.
FIG. 2 illustrates another embodiment of the controlled zone defrosting system 10 that also has a control unit 12 shown connected to a battery 14 and to a plurality of defrosting devices 16. Also shown is a photovoltaic device, or solar panel, 18 connected to the control unit 12 to provide an additional supply of electrical energy.
Shown in FIG. 3 is a block diagram illustrating the basic parts of the control unit 12 of the controlled zone defrosting system 10 of FIGs's. 1 and 2. A selection unit 20 is connected to a switching unit 22, as is also a sensing unit 24. A power input coupling 26 having a first input terminal for connecting a battery 14 and a second input terminal for connecting a solar panel 18 to the defrosting system is coupled to the switching unit 22, and output terminals 28 are also connected thereto. p The selection unit 20 has a plurality of switches for selecting zones to which electrical energy is to be directed and also for selecting the criteria governing the energy disbursement. Each zone may represent, on an associated vehicle, an area to be defrosted, for example, the driver side or passenger side of the windshield, the rear window, etc. Electrical energy may also be directed to heaters in, for example, the steering wheel.
The sensing unit 24 includes a plurality of well-known devices for sensing such factors as time, temperature and the electrical energy remaining in the battery. In typical operation, the defrosting system may be set to begin applying electrical energy to the electrically conductive glass coating material of the defrosters located on the driver and passenger sides of the windshield and on the rear window fifteen minutes before the vehicle is to be driven; and to begin applying energy to the steering wheel heater ten minutes later. The energy would be directed to the heating devices in the selected zones only if the temperature is sensed as being below a selected level and only if, or for as long as, the available electrical energy remaining in the battery is sensed as being above a certain level. As the amount of remaining electrical energy decreases, zones having ever higher assigned priorities will no longer be supplied therewith.
The switching unit 22 includes switching devices for connecting electrical energy supplied to the power input coupling 26 to the output terminals 28 as a function of the criteria set into the selection unit 20 and of the conditions monitored by the sensing unit 24.
If a photovoltaic device, or solar panel, 18 is also connected to the control panel 12, as in FIG. 2, its output of electrical energy may be monitored by the sensing unit 24 and used to supplement that obtained from the battery 14. If the output of the photovoltaic device 18 is sufficient, no electrical energy need be taken from the battery 14; in fact, electrical energy generated by the photovoltaic device 18 may be used to recharge the battery 14.
While the controlled zone defrosting system has been shown and described in considerable detail, it should be understood that many changes and variations may be made thereto without departing from the spirit and scope of the invention.