Patent Application
20180257457
The present application relates to vehicle equipment heating techniques, and more particularly, but not exclusively, relates to techniques to more rapidly heat-up a vehicle device with a heating element energized by multiple electric power sources. Additionally or alternatively, the present invention relates to multiple modes of applying heat to a vehicle device.
There is a persistent desire to provide a more comfortable operating environment for vehicle occupants, including both vehicle passengers and operators. Among other things, this desire has resulted in better control over air temperature in the occupant compartment of the vehicle. Unfortunately, environmental control of a vehicle occupant compartment can prove difficult when there is an appreciable thermal time constant, when operating under extremely cold conditions, or when power available to perform warming is limited. Reliable heating of various vehicle equipment features during cold or otherwise inclement weather can be particularly challenging. Indeed, especially during cold weather, there is a pressing desire to more rapidly heat-up certain vehicle devices—particularly those structured for direct contact with an occupant's skin or apparel. Thus, there is an ongoing demand for further contributions in this area of technology.
By way of transition from this Background to subsequent sections of the present application, one or more abbreviations, acronyms, and/or definitions are set forth below and supplemented by example or further explanation where deemed appropriate. Among other things, these definitions are provided to: (a) resolve meaning sometimes subject to ambiguity and/or dispute in the applicable technical art(s) field(s) and/or (b) exercise the lexicographic discretion of any named inventor(s), as applicable:
1. “Direct Current” (DC) means an electric current that is unidirectional, a flow of like electrical charge that is unidirectional, an electric current that is not of the AC type, or an electric current or electric charge flow that does not reverse direction. Magnitude of an electric current of the DC type can vary from zero to a maximum that depends on the electrical load drawing such electric current, the capability of the equipment supplying the electric current, any variation in magnitude of the voltage supplied by such equipment, or the like. To the extent an electric current reverses direction on a temporary, aperiodic basis due to failure, operator error, reactive loading, poor electrical grounding, noise, or the like; any duration of the electric current prior or subsequent to such reversal is the DC type. Certain components of DC electric power supplies and associated equipment often utilize protective diodes or other semiconductors that prevent electric current reversal of the supply overall or for selected parts thereof likely to be irreversibly damaged (such as certain vehicle supply batteries, various accessories, and the like). Even so, any relatively long, aperiodic or periodic duration of unidirectional electric current is still considered DC for the purposes of the present application even if there is a relatively short or minor polarity reversal.
2. “DC Voltage” (VDC) means a voltage or electric potential that provides electric current or electric charge flow of the DC type, is not an AC voltage, or a voltage output that does not reverse polarity. Magnitude of a DC voltage can vary between zero and a maximum that depends on the electrical load to which such DC voltage is supplied, the capability of the equipment supplying the DC voltage, the magnitude of electric current supplied by such equipment including any variation in such magnitude, or the like. Commonly electric power supplies output a DC voltage with a magnitude that remains approximately constant over time subject to a specified tolerance or is supplied within a specified magnitude range. For a nominal 12 VDC vehicle power supply typical of many automobiles, the DC voltage magnitude can vary considerably, sometimes as low as 11 VDC when the supply is solely supported by a highly discharged lead-acid vehicle battery to as much as 15 VDC from the a rectified output of a polyphaser alternator of the supply. VDC magnitude of a typical vehicle power supply can further vary depending on a number of factors such as temperature, state of charge and the type of a vehicle supply battery (or batteries) included (if any), characteristics of any associated alternator or motor/generator from which a rectified VDC is derived, degree and nature of any voltage regulation, electrical loading of the supply, whether the vehicle is fully electric and/or has hybrid characteristics, and the like. Many DC voltage supplies provided by vehicles are produced by full-wave rectification of a three-phase alternator type of electric power generator driven by an internal combustion engine. These systems usually include a primary battery across the supply voltage that is charged while the alternator is receiving mechanical rotary power from the engine. When the engine is not in operation, this battery provides electric power for engine start-up, powering various vehicle accessories, and the like. Depending on the presence, type, and degree of voltage regulation and/or filtering provided in a given vehicle DC voltage power supply, a slight voltage ripple may be present on top of a generally constant DC voltage offset from the zero magnitude level—particularly for that part of the vehicle supply that charges the supply battery.
3. “Alternating Current” (AC) means a time-varying electrical current or electrical charge flow that: (a) periodically reverses direction (such as a repeating sinusoidal waveform, square waveform, triangle waveform, or the like), or (b) reverses direction on an aperiodic basis but averages about the same amount of time in both the unreversed and reversed directions.
4. “AC Voltage” (VAC) means a time-varying voltage that: (a) periodically reverses polarity (such as a repeating sinusoidal waveform, square waveform, triangle waveform, or the like), or (b) reverses polarity on an aperiodic basis but averages about the same amount of time with both the unreversed and reversed polarities.
5. “Pulse Width Modulation (PWM) means a periodic, time-varying signal (electric current, voltage, or both) with an established frequency and corresponding period with one pulse per period; where the pulse width relative to the given period varies over the range from zero percent (0%), that is no pulse for the given period, through one hundred percent (100%), that is a pulse as wide as the given period, and any of a number interim pulse widths relative to the period in between 0% and 100%. These interim pulse widths may be limited to a discrete finite set (say every 5% interval: 0%, 5%, 10%, 15%, . . . 100%) or continuously adjustable over such range. The resulting PWM pulse train is typically of a DC type with the pulses varying between a magnitude of zero and some set VDC, although its variants include AC types or types with different DC offsets.
6. “Single-Pole, Double-Throw” (SPDT) refers to a mechanical switch, an electromechanical relay, a semiconductor switch, or other type of switch with one common contact (the “single-pole”) that alternates electrical connection between two different contacts (the “double-throw”) whenever its setting changes. So if the common contact is electrically connected to a first one of the different contacts, then changing its setting breaks the electrical connection between the common contact and the first one of the different contacts, and instead the common contact makes an electrical connection with the second one of the different contacts. Changing the setting again reestablishes electrical contact with the first one of the different contacts and the common contact, and so on. The setting may be changed by mechanical movement, electrical signaling, optically, or the like.
7. “Double-Pole Double-Throw” (DPDT) refers to a mechanical switch, an electromechanical relay, a semiconductor switch, or other type of switch with two common contacts (the “double-pole”) that both alternate electrical connection between its own unique pair of two different contacts (the “double-throw”) (for a total of four contacts besides the two common contacts) whenever its setting changes. So if the first common contact is electrically connected to a first one of the first pair of contacts and the second common contacts is electrically connected to a first one of the second pair of contacts, then changing the setting breaks the electrical connection between both the common contacts and the first one of each of the first and second pairs of contacts, and instead the first common contact makes an electrical connection with the second one of the first pair of contacts and the second common contact makes an electrical connection with the second one of the second pair of contacts. Changing the setting again reestablishes the first electrical configuration, and so on. The setting may be changed by mechanical movement, electrical signaling, optically, or the like. It should be appreciated that a DPDT switch acts like two SPDT switches that are ganged together to always change setting simultaneously.
The above listing of one or more abbreviations, acronyms, and/or definitions apply to any reference to the corresponding subject terminology herein unless explicitly set forth to the contrary. Any acronym, abbreviation, or terminology defined in parentheses, quotation marks, or the like elsewhere in the present application likewise shall have the meaning imparted thereby throughout the present application unless expressly stated to the contrary or unless identical to an entry of the immediately preceding numerical listing of abbreviations, acronyms, and/or definitions, in which case such listing prevails. Any acronym, abbreviation, or definition provided herein applies irrespective of whether the abbreviated, defined and/or otherwise represented terminology is in lower case, upper case, or capitalized form, unless expressly stated to the contrary.
Certain implementations of the present application include unique techniques to reduce the time it takes a vehicle heating element to reach a desired temperature. Other forms include unique adaptations, additions, alternatives, applications, arrangements, articles, aspects, circuitry, configurations, developments, devices, discoveries, features, instrumentalities, kits, machines, manufactures, mechanisms, methods, modifications, operations, options, procedures, processes, refinements, systems, upgrades, uses, vehicles, variants of any of the foregoing, or the like to more quickly warm a vehicle device with multiple electrical energy sources via associated circuitry. Still a further aspect is directed to a vehicle with a heating system including circuitry with a heating element selectively energized in each of several operational modes in accordance with circuitry-executed operating logic in response to one or more inputs to provide heat to a vehicle device.
In a further form of the present application, a heating element rapidly heats-up a vehicle device from an unpleasantly cold temperature to a warmer temperature when supplied electric energy from multiple sources in concursion. The device is structured to make contact with an occupant inside the vehicle who finds the warmer temperature more agreeable than the cold temperature. In one nonlimiting example, the cold temperature is less than or equal to approximately 40° Fahrenheit (F) and the warmer temperature is greater than or equal to approximately 65° F. In a further refinement of this example, the cold temperature is less than or equal to approximately 32° F. (equivalent to 0° Celsius (C)), and the warmer temperature is greater than or equal to 72° F. In still other forms of the present application, no particular cold or warm temperature is involved.
While a vehicle device contacted by an occupant inside the vehicle is a good candidate for heating-up to a comfortable temperature, other good candidates for heating include vehicle-mounted: windows, mirrors, cameras, or the like that are used to view surroundings external to the vehicle by an occupant inside the vehicle. Under certain meteorological conditions (like temperatures below freezing—32° F. or less), such devices can become at least partially occluded by frost, snow, ice, or the like—potentially impairing operator visibility so much that vehicle operation can become unsafe. Nonetheless, by bringing this kind of device to a warmer temperature (say significantly greater than 32° F.)—defrosting and thawing of visually obstructive frost, snow, and ice by a sufficient amount may restore visibility to the level sought to safely operate the vehicle. Under yet other meteorological conditions, rain, mist, or fogging may at least partly block operator visibility through a window or windshield, or with a vehicle-mounted outdoor mirror or camera, which can also be addressed by heating to a sufficiently warm enough temperature.
Other implementations of the present application include increasing temperature of a vehicle steering device with a heating element energized by a first DC voltage from a vehicle power supply electrically coupled to a rechargeable energy source. In response to an operational state change caused by the increasing of the temperature, electrical connectivity of the vehicle power supply and the rechargeable energy source undergoes reconfiguration to output a second DC voltage. This second DC voltage energizes the heating element to provide heat to the vehicle steering device and recharges the rechargeable energy source. In certain refinements, the vehicle steering device is a steering wheel of the type common to on-road automobiles.
Another arrangement of the present application includes a vehicle and a heating system carried thereby. This system comprises a heating element that when energized, heats-up an outer surface of one or more of: a vehicle control, a seat base, a seat back, a vehicle-mounted cushion, a headrest, an armrest, a center console, a floorboard, a floor mat, a window, a windshield, a vehicle-mounted mirror, and a vehicle-mounted camera. This arrangement further includes: a vehicle power supply to output a DC supply voltage, a rechargeable energy source to output a DC source voltage, an input device to initiate heat-up of the outer surface by the heating element, and control circuitry. This control circuitry responds to the input device to provide the vehicle power supply, the rechargeable energy source, and the heating element in a first circuit to output a first DC voltage to electrically energize the heating element to increase the temperature of the outer surface at a first rate. In response to an operational state change caused by the increase of the temperature, the control circuitry couples the vehicle power supply, the rechargeable energy source, and the heating element in a second circuit to output a second DC voltage to provide heat to the outer surface at a second rate less than the first rate with the second circuit being further operable to charge the rechargeable energy source.
Yet other forms of the present application are directed to a vehicle with a heating system and a process for using the same. In one implementation, this heating system/process includes a vehicle power supply electrically coupled to a rechargeable energy source for energizing a heating element to increase temperature of a vehicle device at a first rate. This vehicle device is structured for contact by skin or apparel of a vehicle occupant or for viewing surroundings outside the vehicle from inside it. The heating system/process also provides for detecting depletion of the rechargeable energy source, and increasing the temperature of the vehicle device at a second rate less than the first rate with the heating element energized from the vehicle power supply in response to the depletion. Also included is determining if the vehicle device temperature is greater than or equal to a target level, and controlling energization of the heating element to approximately maintain the target level of the device temperature.
Still a further arrangement is directed to: heating a steering wheel with a heating element energized with a first DC voltage from a vehicle power supply electrically coupled to a rechargeable energy source. Responsive to an operational state change caused by the heating, the heating system/process continues by providing heat to the steering wheel with the heating element energized with a second DC voltage from the vehicle power supply that is less than the first DC voltage, and recharging the rechargeable energy source with the second DC voltage.
The above introduction to the present application is not to be considered exhaustive or exclusive in nature—merely serving as a forward to further advances, advantages, approaches, attributes, benefits, characteristics, contributions, efficiencies, features, gains, goals, improvements, incentives, influences, objectives, operations, principles, progressions, purposes, savings, uses, variants of any of the foregoing, or the like. Other adaptations, additions, alternatives, apparatus, applications, arrangements, articles, aspects, circuitry, configurations, developments, devices, discoveries, forms, implementations, instrumentalities, kits, machines, manufactures, mechanisms, methods, modifications, operations, options, procedures, processes, refinements, systems, upgrades, uses, vehicles, variants of any of the foregoing, or the like shall become apparent from the description provided herewith, any attendant drawing figures, any patent claim appended hereto, or any other information provided herewith.
Throughout the present application, occurrence of a reference numeral in one drawing figure like that in a previously introduced drawing figure refers to the like feature already described for the previous occurrence thereof. The accompanying drawing figures incorporated herein and forming a part of the specification, illustrate several aspects of the present application, and together with the description explain certain principles thereof.
In the following description, various details are set forth to provide a thorough understanding of the principles and subject matter of the content described or illustrated herein, or set forth in any patent claim appended hereto. To promote this understanding, the description refers to certain representative aspects—using specific language to explicate the same accompanied by any drawing figures to the extent the description subject matter admits to illustration. In other instances, when the description subject matter is well-known, such subject matter may not be described in detail and/or may not be illustrated to avoid obscuring information that is to be conveyed in detail. Considering further any patent claim that follows, those skilled in the relevant art will recognize that the same can be practiced without one or more specific details included in the description. Further, the full scope of any patent claims can encompass, cover, read on, or otherwise extend or apply to any instance in which one or more various unexpressed aspects exist in addition to that subject matter made explicit therein. Such unexpressed aspects can be directed to anything that is additional to that explicitly recited with respect to any patent claim that follows. Accordingly, this description sets forth representative examples only and does not limit the scope of any patent claims provided herewith.
Referring additionally to
In another cut-away of
Specifically referring to
Operator input circuitry 42b includes operator input device 38. Operator input device 38 provides a switch 44 of the pushbutton type that toggles between three different states, transitioning from one to the next with each subsequent push by the operator. Upon start-up of vehicle 22, heating circuitry 40, control circuitry 50, and operator input device 38 begin in a first state absent any operator manipulation of switch 44 unless vehicle 22 was stopped in the third state to be more specifically described hereafter. In this first state, switch 44 is unlit, and heating of steering wheel 30 is inactive or halted (heating inactive state) unless subject to the overriding third state. If the operator pushes switch 44 once after start-up of vehicle 22, then it emits one color of light from Light Emitting Diode (LED) 44a and signals control circuitry 50 to activate heating of the steering wheel 30 with heating system 20 just a single time—effectively transitioning from the first state to a second state. This second state (single heating state) for steering wheel 30 is reset to the inactive state (first state) whenever vehicle 22 is stopped and restarted—that is it returns to the first state (heating inactive state). If the operator pushes switch 44 a second time after start-up of vehicle 22, then it emits a different color of light from LED 44b than the color emitted by LED 44a and transitions from the second state to a third state. In this third state, heating of steering wheel 30 is performed automatically whenever vehicle 22 is started and temperature T of steering wheel 30 (as gathered with thermistor 34a) is less than or equal to an Auto-start temperature Level (AL) selected with rotary dial 46 (automatic heating state). Dial 46 may be a form of potentiometer, rheostat, multi-position switch, or other device suitable to convey the automatic threshold level AL to control circuitry 50. This automatic heating state reactivates every time vehicle 22 is stopped and re-started, automatically emitting light from LED 44b upon start-up to inform the vehicle operator that the third state (automatic heating state) is active. However, pushing the switch 44 again without stopping vehicle 22 reestablishes the first state during which heating of steering wheel 30 is inactive and switch 44 is unlit. Provided vehicle 22 is not stopped, pushing switch 44 yet again transitions to the second state (single heating state), and still another time transitions to the third state (automatic heating state), and so on. Control circuitry 50 receives information from operator input device 38 via input 38a to track which of the three states currently applies, and also monitors whenever vehicle 22 stops in relation to the applicable state to determine whether to the next start-up of vehicle 22 will be in the first state (heating inactive state) or the third state (automatic heating state). Upon determining a given state is applicable, control circuitry 50 initiates appropriate action by the balance of heating circuitry 40 as appropriate—particularly directing any change as to the status of switch circuitry 80 as further described in connection with
Control circuitry 50 includes various circuits to: detect, receive, and condition input signals in an analog or digital format; generate, transmits, and condition output signals in an analog or digital format; and otherwise perform in a manner suitable to operate in the manner described hereinafter. Control circuitry 50 further includes Engine Control Unit (ECU) 50a that comprises various circuits and architecture to control a corresponding engine and/or drive train of vehicle 22 and optionally at least some other aspects of operation of vehicle 22. In one form of heating circuitry 40, control circuitry 50 is completely provided by ECU 50a, while in others control circuitry 50 and ECU 50a are separate and independent from one another. In still other forms, control circuitry 50 and ECU 50a may overlap in some respects. In yet a further form, ECU 50a is absent. Control circuitry 50 further includes microcontroller 51 equipped with a Central Processing Unit (CPU) 50b and corresponding memory 50c. Microcontroller 51 typically includes digital inputs and outputs, and analog inputs and outputs, one or more interrupt inputs, one or more waveform generation outputs, one or more timers, one or more analog-to-digital converters (ADCs), one or more digital-to-analog converters (DACs), one or more serial and/or parallel communication buses, and such other circuitry suitable to operate in the manner described herein. Microcontroller 51 includes the capability to process, store, and communicate information in accordance with specified operating logic—such operating logic may be in the form of analog circuitry; digital circuitry; hardwired, firmware, or software programming instructions; or a combination of any of the foregoing. CPU 50b can be of a reduced instruction set computing (RISC) architecture, a complex instruction set computing (CISC) architecture, a parallel and/or serial instruction pipelining architecture, a multiprocessing and/or multitasking architecture, or such other architecture as would occur to those of ordinary skill in the art. Memory 50c can be of a single type or different types. Such types may include various nonvolatile varieties such as read-only memory (ROM) that can be programmed only a single time (PROM), electrically erasable PROM that can be reprogrammed, but usually one for a limited number of times (EEPROM), or flash memory; or volatile types such as dynamic random access memory (DRAM), static random access memory (SRAM), and a high speed content addressable type (cache), among many other more exotic types and numerous variants thereof. In one arrangement of microcontroller 51, a nonvolatile portion of memory 50c, such as a flash, PROM, or EEPROM stores any operating logic provided in the form of programming instructions executable by CPU 50b. In a different arrangement for which at least some of the operating logic is in the form of programming instructions, memory 50c also includes a content-addres sable volatile cache to pre-fetch such instructions and/or execute alternative instruction pipelines; volatile DRAM or SRAM for intermediate, temporary storage of data and/or such instructions; and one or more nonvolatile semiconductor memory varieties for the long-term storage of such instructions and certain types of other information. Control circuitry 50 is responsive to monitoring circuitry 42 (inclusive of temperature input circuitry 42a and operator input circuitry 42b) to execute its operating logic in response and generate a number of outputs, including: control output 51f to steady-state temperature control circuitry 140a, four control outputs 51a, 51b, 51c, and 51d to circuitry 58, and one control output 51e to connection switch 52 of switch circuitry 80.
With heating element 32 being electrically grounded at grounded terminal 32b, its receipt of electric power to generate heat at a given level depends on the electrical characteristics presented to it through connection switch 52 (included in switch circuitry 80). More specifically, input terminal 32a of connection switch 52 is electrically coupled to common contact 53 of connection switch 52. In response to appropriate signaling from control circuitry 50 on control output 51e, connection switch 52 toggles common contact 53 between electrical coupling with contact 53a and contact 53b. When common contact 53 of connection switch 52 electrically couples with contact 53a, heat-up circuitry 58 is electrically connected to contact 53a via electrical coupling 97, which in turn electrically connects to input terminal 32a of heating element 32. In contrast, when common contact 53 of connection switch 52 electrically couples with contact 53b, steady-state temperature control circuitry 140a is electrically connected to contact 53b via amplified output 160, which in turn electrically connects to input terminal 32a of heating element 32. Connection switch 52 is an electromechanical relay, a solid-state relay, a transistor-based solid-state switch, or another switching device suitable to operate in the manner described. What constitutes signaling appropriate to cause common contact 53 to change electrical coupling between contact 53a and contact 53b depends, at least in part, on the specific variety of connection switch 52. In some forms, common contact 53 electrically couples with contact 53a or contact 53b depending on a binary logic level of a signal on control output 51e with electrical coupling between common contact 53 and one of contact 53a and contact 53b occurring while the signal is “true” and coupling between common contact 53 and the other of contact 53a and contact 53b occurring while the signal is “false”—where any change in a signal characteristic could be used to distinguish between true and false. In other forms, a pulse on control output 51e of a certain character causes common contact 53 to toggle between electrical coupling with contact 53a and contact 53b—where such character could relate to pulse magnitude, pulse width/duration, time separating pulses, a combination of these, or as otherwise would occur to those of ordinary skill in the art. In still different forms, the signal causing common contact 53 to change electrical coupling from one to the other as between contact 53a and contact 53b relates to a particular signal waveform, change in frequency, an amplitude variation, a combination of the foregoing, or as otherwise would occur to those of ordinary skill in the art. Further, in certain variants, it should be recognized that a signal on control output 51e causing common contact 53 to switch from contact 53a to contact 53b may be different than that causing common contact 53 to switch from contact 53b to contact 53a.
Referring additionally to
Heat-up circuitry 58 also includes charger circuitry 77 structured to facilitate charging of the one or more electrochemical cells 72 of rechargeable battery 75 in response to detecting depletion thereof. In certain implementations, charger circuitry 77 is based on the quantity, arrangement, and specific electrochemical characteristics of such electrochemical cells 72—being structured to perform recharging in accordance with a well-defined profile for the particular configuration of electrochemical cells 72, while monitoring various characteristics of the same (e.g. temperature(s) of the one or more cells 72, electric current discharge history, voltage history during discharge, or the like) to reduce the likelihood of incurring damage thereto. In some of these implementations, the profile encompasses multiple stages, while others may be of only a single-stage variety. In one instance directed to the Li-ion variety of electrochemical cells 72, the profile performed by charger circuitry 77 includes a constant current stage followed by a constant voltage stage, and can include a balancing stage in between to the extent charge balancing between different electrochemical cells 72 has not been previously established. In a variety of rechargeable battery 75 incorporating NiMH cells, charger circuitry 77 performs: (1) a fast charging stage that terminates based on detection of a certain voltage drop and/or a certain temperature increase indicating rechargeable battery 75 is fully charged and (2) a trickle charging stage performed at a fixed, low electric current magnitude relative to the other stage to maintain the charge and counteract any self-discharge. As a single stage alternative for NiMH-based configurations, only trickle charging is performed. For a different form of rechargeable battery 75 (and correspondingly rechargeable energy source 70) comprised of the LA type of electrochemical cells 72 in a deeply discharged state, one kind of charging profile includes three stages: (1) a bulk charging stage that applies a generally constant electric current until the battery is approximately 70%-80% charged, (2) boost charging stage (absorption/topping charging) that applies a voltage too high for the battery to endure indefinitely without the risk of damage (an overvoltage) but tolerable in the short-term until the battery is about 95% charged with electric current gradually decreasing until it falls below a level triggering the next stage, and (3) a float charging stage (preservation charging) that applies a constant voltage the battery can tolerate indefinitely (compared to the overvoltage) to fulfill the last 5% of charge capacity and otherwise counteract self-discharge. In still another instance, charging may be performed in only a single stage of the float or trickle charging variety, such as the preservation charge approach common to the way an LA type of vehicle supply battery 65 is charged by vehicle power supply 60. It should be appreciated that the specific recommendations for charging rechargeable battery 75 can vary greatly with the electrochemical characteristics of electrochemical cells 72 and the like with the particulars of charger circuitry 77 being structured accordingly.
In certain implementations of heat-up circuitry 58, charger circuitry 77 is partially or completely embedded in the same device containing the one or more electrochemical cells 72 or otherwise defining the rechargeable energy source 70. In still other forms of the heat-up circuitry 58, charger circuitry 77 is absent—particularly in those cases for which recharging is suitably performed using the DC voltage output from vehicle power supply 60 alone in a single charging stage. For those forms of rechargeable energy source 70 including electrochemical cells 72 arranged in series to provide a maximum voltage too high to be recharged without utilizing techniques to increase the DC voltage output by vehicle power supply 60, then charger circuitry 77 includes circuitry directed to converting such DC voltage to a higher level adequate to perform recharging in view of such maximum voltage. As part of or separate from charger circuitry 77, certain forms of heat-up circuitry 58 include one or more protective diodes or other unidirectional electric current flow devices to prevent reverse flow of electric current through any of the one or more electrochemical cells 72 contained in rechargeable energy source 70, a sensor to detect excessive temperature of rechargeable battery 75 to halt use of rechargeable battery 75 or otherwise adjust operation of heat-up circuitry 58 accordingly, and/or such other protective measures as would occur to those of ordinary skill in the art.
Referring to both
Under the direction of control circuitry 50, switch circuitry 80 provides two alternative circuits including heating element 32, vehicle power supply 60 and rechargeable energy source 70 as perhaps best illustrated in
SPDT relay 100 includes common contact 102, contact 104, and contact 106. SPDT relay 100 is responsive to appropriate signaling by control circuitry 50 via control output 51b to alternate common contact 102 between electrical connection with either contact 104 (not shown) or contact 106 (shown in
Heat-up circuitry 58 defines an electrical interconnection between DC voltage bus 61, positive terminal 64a of vehicle supply battery 65, contact 94a of DPDT relay 90, contact 96b of DPDT relay 90, and contact 104 of SPDT relay 100—where such interconnection corresponds to DC voltage supply node 91. During operation, DC voltage bus 61 imparts a positive electric potential (voltage) to DC voltage supply node 91 relative to electrical ground. Negative terminal 64b, contact 94b of DPDT relay 90, and grounded terminal 32b of heating element 32 are electrically grounded corresponding to an electric potential (voltage) of approximately zero in relation to that at DC voltage supply node 91. Positive terminal 74a of rechargeable energy source 70 is electrically coupled to common contact 92b of DPDT relay 90 in correspondence to electrical node 131. Negative terminal 74b of rechargeable energy source 70 is electrically coupled to common contact 92a by electrical coupling 79, and common contact 92a electrically couples with contact 94a of DPDT relay 90, which in turn electrically interconnects with DC supply voltage node 91—so that negative terminal 74b of rechargeable energy source 70 electrically couples with positive terminal 64a of vehicle supply battery 65 and likewise DC voltage bus 61. As illustrated, common contact 92b is electrically coupled to contact 96a of DPDT relay 90 that is electrically coupled to contact 106 of SPDT relay 100 by electrical coupling 93. Common contact 102 is electrically coupled to contact 106 of SPDT relay 100 and is electrically connected to common contact 122 via electrical coupling 95. Common contact 122 of SPDT relay 120 electrically connects with contact 126 per as shown in
Heat-up circuitry 58 further includes detection circuitry 130 to determine whether performance of rechargeable energy source 70 indicates a state of depletion warranting recharging thereof in lieu of continued use. Such depletion corresponds to an operational state change of heating system 20 that often depends on the specifics of the one or more electrochemical cells 72 comprising rechargeable energy source 70 and/or potentially one or more other aspects thereof. In many applications, depletion detection is based on the DC source voltage falling below an identified threshold and/or decreasing a certain amount relative to one or more influential factors, such as temperature, signal noise, transient behavior, or the like. Alternatively or additionally, the recognition of depletion results from: identification of decreasing trends or patterns of DC source voltage, evaluation of the discharge history for rechargeable energy source 70, tracking power or capacity of rechargeable energy source 70, or the like. Detection circuitry 130 includes comparator 133 with noninverting input 136, inverting input 134, and output 132. Noninverting input 136 is electrically interconnected to electrical node 131 along with positive terminal 74a of rechargeable energy source 70 and common contact 92b of DPDT relay 90 so that comparator 133 receives a representation of the DC supply voltage from rechargeable energy source 70. Inverting input 134 of comparator 133 is electrically connected to adjustable voltage reference 140 to receive a voltage reference signal therefrom that is designated “Vref” herein. Comparator 133 delivers a binary signal to control circuitry 50 that is indicative of a comparison of Vref input to inverting input 134 to the DC source voltage input to noninverting input 136. If the DC source voltage from rechargeable energy source 70 is greater than Vref, then comparator 133 delivers a binary result from output 132 to control circuitry 50 that represents a “true” condition or equivalently a logical one. If the DC source voltage is less than or equal to Vref, then comparator 133 delivers a binary result from output 132 to control circuitry 50 that represents a “false” condition or equivalently a logical zero without feedback 138. Detection circuitry 130 monitors the DC source voltage via noninverting input 136 for comparison to the adjustable voltage reference Vref, and detects depletion of rechargeable energy source 70 that warrants recharging in lieu of continued use by generating a “false” binary result from output 132 when it is reached.
When detection circuitry 130 signals the depletion of rechargeable energy source 70 through output 132, control circuitry 50 responds by reconfiguring heating element 32, vehicle power supply 60, and rechargeable energy source 70 in the first circuit to a second circuit including heating element 32, vehicle power supply 60, and rechargeable energy source 70 with a different electrical connectivity than the first circuit. This second circuit implements the second/slow mode of heating-up steering wheel 30, while the first circuit implements the first/fast mode of heating-up steering wheel 30. More specifically, control circuitry 50 responds to the depletion detection by signaling DPDT relay 90 via control output 51a and SPDT relay 100 via control output 51b to change from the illustrated configuration of
For both the first/serial circuit to perform the first/fast mode of heating-up steering wheel 30 and the second/parallel circuit to perform the second/slow mode of heating-up steering wheel 30, the configuration of SPDT relay 120 remains the same. If control circuitry 50 transmits appropriate signaling through control output 51c to SPDT 120, it reconfigures so that common contact 122 is electrically coupled to contact 124 instead of contact 126. With the status of connection switch 52 remaining the same as shown in
Depletion detection for rechargeable energy source 70 with detection circuitry 130 and the determination that temperature T attains target temperature level TL with temperature sensor 34 via monitoring circuitry 42 are two different ways an operational state change of heating system 20, its constituent heating circuitry 40, and/or corresponding operations takes place. For other forms of the present application an operational state change may be caused by other events, activities, or occurrences besides depletion detection or attainment of target temperature level TL.
Steady-state temperature control circuitry 140a defines a third circuit with heating element 32 operable to regulate the delivery of heat to steering wheel 30 in such a manner that approximately sustains its temperature T at the target temperature level TL. For this third circuit, control circuitry 50 monitors temperature T with monitoring circuitry 42 to determine whether there is any differential (error) between temperature T of steering wheel 30 and target temperature level TL of sufficient magnitude to cause an adjustment. Upon the determination to make such adjustment, Control circuitry 50 generates a modulated control signal structured to correct such differential and transmits the modulated control signal to amplifier circuitry 150 via control output 51f. This modulated control signal is more particularly a type of a PWM control signal. The duty cycle of this PWM control signal can be varied with respect to a predefined range, and is particularly selected to provide the amount of heat to steering wheel 30 that corrects the differential (error) to the extent it exceeds acceptable limits, or otherwise counteracts any detected level of heat loss or thermal dissipation from steering wheel 30 to approximately sustain temperature T at target temperature level TL. The PWM duty cycle of the modulated control signal increases when temperature T falls below target temperature level TL and decreases when temperature T is exceeds the target temperature level TL. The modulated control signal is provided through control output 51c to amplifier circuitry 150. Amplifier circuitry 150 includes preamplifier 56 implemented with an operational amplifier (op amp) and transistor array 151. The modulated control signal is transmitted from control circuitry 50 to noninverting input 56a of preamplifier 56 via control output 51f. The inverting input 56b of preamplifier 56 takes negative feedback from output 56c via voltage divider 57. Output 56c is connected to resistor 57b which is connected in series to resistor 57a which is in turn connected to ground. The inverting input 56b is connected between resistors 57a and 57b. Preamplifier 56 provides appropriate signal buffering, gain, and conditioning to generate a time-varying transistor drive signal representative of the modulated control signal that is sufficient to drive transistor array 151. Preamplifier 56 transmits this time-varying transistor drive signal from output 56c of preamplifier 56 to transistor array 151. In the described embodiment, transistor array 151 includes four (4) transistors 152 arranged to further amplify the transistor drive signal received from output 56c of preamplifier 56 Transistor array 151 receives the time-varying drive signal from output 56c of preamplifier 56 corresponding to the modulated control signal received by preamplifier 56 at noninverting input 56a. Other embodiments may have more or fewer transistors depending on design parameters and preferences. This time-varying drive signal from preamplifier 56 is applied to base b of each of the transistors 152 included in transistor array 151. The collector c of each transistor 152 is electrically coupled to DC voltage bus 61 as provided by vehicle power supply 60. A limiting resistor is electrically coupled between emitter e of each transistor 152 and output 160. Output 160 provides a time-varying energization signal for application to heating element 32 that corresponds to the PWM-type modulated control signal from control circuitry 50.
Some implementations maximize the degree to which operations and conditionals of procedure 220 can be executed in accordance with operating logic by heating circuitry 40 in general and control circuitry 50 more specifically. As introduced in connection with
Procedure 220 receives input signals from monitoring circuitry 42 (
Procedure 220 starts in the center at the top of
Procedure 220 proceeds to operation 226. In operation 226, control circuitry 50 sends appropriate control signals to switch circuitry 80 to electrically couple vehicle power supply 60 in electrical series with rechargeable energy source 70. Heating element 32 is also in electrical series with vehicle power supply 60 and rechargeable energy source 70 to receive the sum of the respective DC supply voltage and DC source voltage thereacross. Accordingly, this high output voltage provides for the flow of more electric current through an electrically resistive form of heating element 32 compared to a lesser voltage of vehicle power supply 60 alone. This higher voltage and current provides for an increase in power electrically dissipated by element proportional to the square of the voltage. Namely, for DC power P is equivalent to the (DC voltage V)2/(electrical resistance R of heating element 32), such that P=V2/R. Accordingly, doubling the voltage V provides for quadruple the power P for a given fixed heating element 32 resistance R. In correspondence, operation 226 provides for a faster heat-up of steering wheel 30 in thermally conductive contact with heating element 32, and more rapidly increases steering wheel temperature T compared to a standard vehicle power supply 60 across heating element 32 alone without rechargeable energy source 70 in electrical series therewith.
From operation 226, procedure 220 continues with operation 228. Operation 228 determines the steering wheel temperature T detected with temperature sensor 34 of monitoring circuitry 42 (e.g. sampling an electrical input from thermistor 34a). From operation 228, conditional 230 is next performed. Conditional 230 tests whether steady-state temperature control with circuitry 140a has been enabled. Because conditional 230 is initially encountered from operations 224, the test is negative (NO) and procedure 220 proceeds along the negative branch (NO) of conditional 230 from connector 235 of
Procedure 220 continues with conditional 242. Conditional 242 tests whether to turn-off warming/heating of steering wheel 30 with heating element 32. If the test of conditional 242 is affirmative (YES), procedure 220 halts or returns until re-activated with operator input device 38. If the test of conditional 242 is negative (NO), such that warming/heating of steering wheel 30 continues, procedure 220 loops back to again perform steady-state temperature control operation 240. After operation 240 is performed once more, the negative branch of conditional 242 (NO) continues to loop back to operation 240 until warming/heating is turned-off following the affirmative branch (YES) of conditional 242 until halting steering wheel heating.
Returning to conditional 254 of
Flow connector 253 of
Several other variations, implementations, forms, and features of the present application are envisioned. In one example, a process includes: energizing a heating element with a DC voltage supply and a DC rechargeable source to increase a temperature of a steering wheel at a first rate; increasing the temperature at a second rate less than the first rate with the heating element energized from the DC voltage supply after detecting the DC rechargeable source is depleted; reaching a target level of the temperature; and controlling energization of the heating element to approximately maintain the temperature at the target level.
Yet another example comprises: energizing a heating element with first voltage including a supply voltage added to a source voltage from a rechargeable source to increase temperature of a steering wheel at a first rate; increasing the temperature at a second rate less than the first rate with the heating element energized by the supply voltage after detecting a depletion of the rechargeable source; determining the temperature reaches a target level; and controlling energization of the heating element to approximately maintain the temperature at a target level.
Another example is directed to a process, comprising: energizing a heating element to increase a temperature of a steering wheel at a first rate from a vehicle power supply electrically coupled to a rechargeable energy source; detecting an energy depletion of the rechargeable energy source; increasing the temperature at a second rate less than the first rate with the heating element energized from the vehicle power supply in response to the energy depletion; and controlling energization of the heating element to approximately maintain the temperature at a target level when the temperature reaches the target level.
In a further instance a method according to the present application includes: heating a steering wheel with a heating element energized by a first voltage from the DC power supply and a DC rechargeable source; providing heat to the steering wheel with the heating element energized by a second voltage output by the DC power supply less than the first voltage in response to an operation state change caused by the heating; and recharging the DC rechargeable source with the second voltage.
Still a further example is directed to a different process, comprising: heating-up a steering wheel with a heating element energized by a DC supply voltage added to an output voltage of a DC rechargeable source; heating the steering wheel with the heating element energized by the DC supply voltage in response to an operational state change caused by the heating; and recharging the DC rechargeable source with the DC supply voltage.
A different example comprising: energizing a heating element to raise a temperature of a steering wheel at one rate with a first voltage from a DC power supply and a DC rechargeable source; increasing the temperature at another rate less than the one rate with the heating element energized with the DC power supply in response to an operational state change caused by the energizing; and recharging the DC rechargeable source with the DC power supply.
A further process of the present application comprises: increasing a temperature of a steering wheel at one rate with a heating element energized by a first voltage greater than a DC power supply voltage; heating the steering wheel with the heating element energized by no more than the DC power supply voltage in response to the operational state change cause by the increasing; and recharging a DC rechargeable source with the DC power supply voltage.
A different example is directed to an apparatus, comprising: a vehicle and a heating system carried thereby. The heating system includes: a vehicle device selected from the group consisting of: a steering wheel, a seat base, a seat back, a vehicle-mounted cushion, a headrest, an armrest, a center console, a floorboard, a floor mat, a window, a windshield, a vehicle-mounted camera, and a vehicle-mounted mirror. This system further includes: a heating element, a vehicle power supply to output a DC supply voltage, a rechargeable energy source to output a DC source voltage, and an operator input device to initiate heat-up of the vehicle device by the heating element. Also included is control circuitry responsive to the operator input device to provide the vehicle power supply, the rechargeable energy source, and the heating element in a first circuit to output a first DC voltage to electrically energize the heating element to increase a temperature of the vehicle device at a first rate. The control circuitry couples the vehicle power supply and the rechargeable energy source in a second circuit to output a second DC voltage less than the first DC voltage in response to an operational state change of the heating system and the second circuit is operable to electrically couple the rechargeable energy source across the second DC voltage to recharge the rechargeable energy source.
Any patent, patent application, or other document cited in the present application is hereby incorporated by reference in its entirety herein—except to the extent expressly stated to the contrary. Any conjecture, discovery, example (prepared or prophetic), experiment, estimation, finding, guesswork, hypothesis, idealization, investigation, operating principle or mechanism, model, representation, speculation, theory, test, test/experimental results, or the like relating to any aspect of the present application is provided to enhance understanding thereof without restricting any patent claim that follows—except to the extent expressly and unambiguously recited to the contrary. The organization of application content under one or more headings promotes application readability or otherwise conforms to certain requirements; however, these headings have no effect as to the scope, meaning, substance, or “prior art” status of such content, unless unambiguously expressed to the contrary thereunder.
No patent claim hereof should be understood to include a “means for” or “step for” performing a specified function (“means plus function clause” or “step plus function clause”) unless signaled by expressly reciting “means for . . . ” or “step for . . . ” before description of a specified function in such clause. Absent an unambiguous indication to the contrary, aspects recited in a process or method claim, including clauses, elements, features, gerund phrases, limitations, or the like may be performed in any order, and any two or more of the same may be performed concurrently or overlapping in time. Indeed, no order of such aspects results just because the process/method claim: (a) recites one of these aspects before another, (b) precedes the first occurrence of an aspect with an indefinite article (“a” or “an”) or no (zero) article (as is commonplace for plural aspects, gerunds, and certain other types of terminology), (c) precedes one or more subsequent occurrences of such aspect with a definite article (“the” or “said”), or (d) the process/method claim includes alphabetical, cardinal number, or roman numeral labeling to improve readability, organization, or the like without any unambiguous express indication that such labeling intends to impose a particular order. Further, to the extent order is imposed as to two or more process/method claim aspects, the same does not impose an order as to any other aspects listed before, after, or between them.
The foregoing has been presented for purposes of representative illustration and description. It is not intended to be exhaustive or to limit any patent claim appended hereto. Obvious modifications and variations may result from the above teachings. All such modifications and variations are within the scope of the appended patent claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. Only representative adaptations, additions, alternatives, apparatus, applications, arrangements, articles, aspects, circuitry, configurations, developments, devices, discoveries, features, forms, implementations, instrumentalities, kits, machines, manufactures, mechanisms, methods, modifications, operations, options, procedures, processes, refinements, systems, upgrades, uses, vehicles, variants of any of the foregoing, or the like have been described, such that any patent claims that follow are desired to be protected.
