Patent Application
20090020280
This invention relates to heating a passenger compartment of a vehicle.
Heating systems used in vehicles generally feature a liquid heat exchanger (heater core) that is heated by radiator fluid, which derives its heat from an engine that produces heat by friction and combustion. A blower fan moves air through, the heater core, where it is warmed, and then into a passenger compartment of the vehicle. Engines can take several minutes to reach a temperature high enough to open a thermostat valve to allow the warm radiator fluid to circulate through the heater core.
In one aspect, a vehicle passenger compartment heating system has a fen that produces air flow, and a heater core that receives heated heating fluid and is disposed upstream of the fan, such that air is drawn through the heater core by the fan for heat exchange with the heating fluid. The heating system also includes a ventilation system directing the air flow produced by the fan throughout the passenger compartment, a supplemental heating element disposed in the ventilation system and arranged to heat air flow produced by the fan, and a heating system controller that controls electrical power to the supplemental heating element as a function of a state of an operable activation switch and a sensed heating-fluid temperature.
In another aspect a method of modifying a factory vehicle heating system in a vehicle having a passenger compartment includes placing a heating element in a factory air box between a factory blower fan and the passenger compartment, installing a temperature sensor to sense a heater core temperature, and providing a controller such that the controller controls the provision of power to the heating element as a function of at least a state of an operable activation switch for the heating system and sensed heater core temperature.
In another aspect, a method of fitting a vehicle heating system including placing a heating element in a factory air box between a factory blower fan and a passenger compartment, installing a temperature switch on a factory heater core to sense a heating fluid temperature in the core, and connecting a switch to the heating element such that electrical power is provided to the heating element as a function of at least a state of an operable activation switch for the heating system and sensed heating fluid temperature.
One or more of the following features may also be included. The supplemental heating element is disposed downstream of the fan. The controller is configured to provide power to the supplemental heating element only when the activation switch is engaged and the sensed temperature is less than about 160° F. for example less than about 140° F. The supplemental heating element is operably connected to a battery that supplies electrical power to the heating system. The battery can be an auxiliary battery that provides power essentially only to the heating system. The controller includes one or more relay switches connecting the supplemental heating element to the battery and controlled by heating fluid temperature and the activation switch. The controller includes a microprocessor running a program that analyzes inputs from the temperature sensor and the activation switch to determine when to provide electrical power to the supplemental heating element. The supplemental heating element is a ceramic heating element. The supplemental heating element is disposed within, a factory air box adjacent to the fan.
An activation element is provided that switches a flow of power from a battery to the heating element on and off, the activation element is controlled by the controller. The controller is connected in such a way that the controller receives inputs from the temperature sensor and the operable activation switch for the heating system. The controller is connected to an engine activation switch and provides power only when the engine is activated. A temperature sensor includes a temperature switch installed on the heater core that is responsive to a desired temperature of the heating fluid. The controller controls the provision of power to the heating element as a function of one or more of a signal received from a wireless transmitter, a sensed ambient temperature of the vehicle's passenger compartment, or a time determined by a clock.
The switch is connected to a battery such that the relay switch provides electrical power to the heating element from, the battery when, the heating system is activated and the sensed heating fluid temperature has not reached a desired temperature for heating the heater core. The switch is connected to an engine activation, circuit and only provides power to the heating element when the engine is activated. A ceramic heating element is placed in the factory air box.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
Referring to
During this period of time, blower fan 11 blows unheated air out towards a ventilation system 4, which carries the air to the passenger compartment of the vehicle through vents 13. This unheated air passes through, and is heated by a supplemental heating unit/beater/heating element 12 prior to passing into the passenger compartment, resulting in heated air, rather than unheated air being provided to any occupants in the passenger compartment during the time period when the heater core 8 is not being heated.
The heating element 12 is placed in front of the blower fen 11 between the blower fan and the passenger compartment for example in a blower box/factory air box 10. By placing the heating element 12 in front of the blower fan 11, the heating element 12 is not exposed to the outside environment as would occur if it were placed proximate to the heater core 8. By not placing the heating element 12 proximate to the heater core 8, where the heater core can absorb some of the heat produced by the heating element 12, more heat is available to heat the air entering the passenger compartment. In some embodiments, the heating element 12 is placed as close to the passenger compartment as possible. In some embodiments, the heating element 12 can be placed behind the blower fan if the factory air box is proportioned to accommodate such placement. In other embodiments, one or more supplemental heating elements and/or blower fans can be placed in other locations in the ventilation system 4 (adapted for such placement) to increase the heating of the passenger compartment and/or to accommodate design requirements of a vehicle's climate control system (such as for individualized climate control).
The heating element 12 can be made of any material compatible with being placed in the ventilation system of a vehicle, for example metallic heating element (nickel-Chromium and iron-chromium-aluminum), silicon, carbide, molybdenum disilicide, thermocouple wire, conductive alloys, fibrothal heating modules, tubothal heating elements, extruded tubes, semiconductor heating elements moduthal refectories, infrared heat, light heat, LED heating, incandescent heating, UV heating, band heaters, ceramic band heaters, mica band heater, tubular heaters, cartridge heaters, duct heaters, indirect, heaters radiant heaters, strip heaters, preferably a ceramic heating element. Heating element 12 can be dimensioned to fit in the chosen location in the heating system 1, such that essentially all of the air blown by the blower fan 11 passes through the heating element 12.
In some embodiments, the heating element 12 heats the air from the blower fan essentially from the time a driver turns the vehicle on until the time when the heater core 8 can provide the heat necessary to; heat the passenger compartment. This arrangement provides an efficient use of the supplemental heating element 12 such that the element does not draw power from a battery 24 except during the time period when the heater core cannot provide energy necessary to heat the passenger compartment.
The control unit 22, as a function of the inputs, determines the appropriate time period during which heating element 12 is powered on and off. In some embodiments, the control unit/controller 22 receives inputs from an engine activation circuit/starter/ignition switch 23 indicating the vehicle is activated and the engine is turned on, a heater switch 25 indicating the operable status of the heater system, and a temperature sensor 29 that senses the temperature of the heater core 8. The supplemental heating element 12 is turned on during the time period between starting the engine and the time the healer core 8 is up to a desired temperature. In this example the heating, element 12 is powered on when the engine is activated, the heating system is activated, and the temperature of the heating core has not reached a predetermined or desired temperature. The desired temperature can be in a range of approximately 140° to 220° F., for example approximately 160° F.
In other embodiments, as shown in
For example, the control unit, using an input from the clock 45, can activate the heating element at a predetermined time. Using the wireless receiver 43 connected to the control unit 22, allows a signal to be sent from, a wireless transmitter 42 (connected to the electronic key, and/or the programmable device, and/or the temperature sensor, and/or the clock, etc) to the control unit to activate the heating element at a desired time as a function, of the inputs. For example, the electronic key 40 can be used to activate the transmitter 42 to send a signal through the receiver 43 to the control unit 22 activating the heating element 12 either by itself or in combination with other inputs (such as an input from a sensor that senses an ambient interior temperature of the vehicle, thus activating the heating element only if the ambient temperature of the passenger compartment is below a predetermined temperature). The receiver can also function to sense the proximity of the electronic key to the vehicle in order to activate the heating element 12 upon approach of the user with the electronic key.
In some embodiments, the heating element 12 receives power from a battery 24, which is a primary battery for powering the vehicle, when the inputs indicate that the heating element needs to be powered on. In other embodiments, the battery 24 can be an auxiliary battery. In other embodiments, the heating element 12 receives power from an alternate power source 24, such as an existing alternator, an upgraded alternator, and/or a capacitor and/or an additional energy generation/storage/regulation device 24. Power received by the heating element 12 may be increased, decreased, or otherwise modified or controlled by utilizing a capacitor or electrical metering or regulation device.
In some embodiments, the control unit 22 can be implemented through a relay switch acting as the control unit 22 with a positive connection of the heating element directly connected to a positive terminal 26 of the battery/power source 24 and a negative connection of the heating element is connected to the relay switch. The relay switch is also connected to the battery ground/body ground/negative terminal 27, to the starter/ignition activation switch 23 (indicating the vehicle is powered on), to the heater switch/factory heating system relay 25, and to the temperature sensor 29, which can be implemented as a temperature switch that turns off when the desired temperature is reached, placed at the heater core 8. (The temperature of the heater core 8 can be determined by sensing a temperature of the engine/engine block, radiator/radiator hose, water pump, or heater core 8 itself. The sensed temperature can be from the surface of a component (internal or external), or a fluid of the engine/engine block, radiator/radiator hose, water pump, or heater core.) The relay functions to power the heating element 12 when the following conditions are met; if the starter switch is on, the heating system is on, and the heater core 8 is not at or greater than, the desired temperature. However, if any of the conditions are not met then the relay switches off the heating element 12.
In other embodiments, inputs can be used such as proximity of an electronic key 40 to the vehicle, using a wireless signal/input sent from a transmitter 42, and/or an ambient interior temperature sensed by a temperature sensor 44 in the passenger compartment, and/or a signal/input from an internal or external clock 45, and/or a signal/input from a programmable device 41, etc.
In some embodiments, the control unit 22 can be implemented through an integrated circuit design, for example a microprocessor, which runs a program analyzing the one or more inputs, such as from, sensors relaying information about whether the engine is switched on or off, whether the heater system is switched on or off, whether the temperature of the heater core has reached the desired temperature, whether an electronic key 40 is in proximity to the vehicle, whether the ambient passenger compartment temperature is below a predetermined temperature, whether a predetermined time has passed, whether a user wishes to activate the heating element using a remote keypad or a switch, and/or whether some other condition programmed into a programmable device has occurred, etc. Based on the inputs, the program determines when the microprocessor sends signals for the heating element 12 to be powered on and off, for example through the activation of a relay switch that provides power to the heating element. In other embodiments, the integrated circuit is implemented through a gated or programmable logic circuit that determines when the heating element 12 is powered on and off as a function of the inputs. The control unit 22 can also be implemented through the electronic control unit of the vehicle.
The heating system can be entirely installed at the factory or the supplemental heating element 12 with the input circuitry and the control unit 22 can be added to a standard factory heating system, lacking these elements. For example, a supplemental heating element 12 is installed into the blower box of the standard factory installed heating system, having a heater core 8, ventilation system 4, and operable activation switch 25 that controls the heater. The supplemental heating element 12 is powered by a standard vehicle battery 24 and is fully integrated with the factory heating system. Using “clip-in” connectors connections can be made to the to the factory heating supply wires for heater switch 25, the ignition/engine activation switch 23. A temperature switch 29 can be added to the heater core to determine when a desired temperature is reached, and connections as discussed above can be made to a relay switch/control unit 22 and the battery 24. Additionally, the power supply for the heating element 12, i.e. the battery 24 can be the battery used to power the vehicle or it can be a secondary battery or alternative power source 24 (as discussed above), such that the heating element 12 does not drain power from the primary vehicle battery. If a secondary battery is present, it can have a battery isolator.
Referring to
A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.
