Hot-air Furnace Patents (Class 236/10)
  • Patent number: 9625169
    Abstract: The disclosure provides an HVAC system, an HVAC controller and a method of operating an HVAC system. In one embodiment, the HVAC controller includes: (1) an interface configured to receive a thermostat call and (2) a processor configured to initiate operation of the HVAC system in response to the thermostat call and control operation thereof based on a temperature difference across a conditioning unit of the HVAC system.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: April 18, 2017
    Assignee: Lennox Industries Inc.
    Inventors: Takeshi Sakai, Peter Hrejsa
  • Patent number: 9572478
    Abstract: A swing prism endoscope with an actuating mechanism that comprises a control element that oscillates in between proximal and distal ends of the endoscope and is coupled to a distally mounted swing prism, a control surface with a variable profile, and an engaging element that contacts the control surface and moves relative to the control surface while contacting the control surface causing the control element to oscillate. The distally mounted swing prism that alters the viewing angle of the endoscope between a forward direction that is substantially parallel to the longitudinal axis of the endoscope and a side direction that is angled relative to the longitudinal axis of the endoscope.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: February 21, 2017
    Assignee: Karl Storz Imaging, Inc.
    Inventor: Hans David Hoeg
  • Patent number: 9476593
    Abstract: A variable secondary air intake device has a baffle member adapted to be attached within an upper area of a fire chamber of the firebox. The baffle member includes a top having a channel member hole therethrough, side walls, a bottom having a plurality of small holes therethrough, and a gas exit opening having side walls and extending through the top and bottom. A hollow chamber member adapted to be placed upon a top surface of the baffle member, the hollow chamber member includes a top having a channel member hole therethrough, and side walls extending downward from the top and forming a chamber having a periphery that includes a plurality of gas exit holes therethrough.
    Type: Grant
    Filed: April 22, 2014
    Date of Patent: October 25, 2016
    Inventor: Emmanuel Marcakis
  • Patent number: 8985472
    Abstract: A rotary aluminum kiln temperature regulation system comprising a temperature sensing device in the kiln that is configured to take temperature readings in an area of the kiln in proximity to the temperature sensing device. The system including a wireless transmitter operatively associated with the temperature sensing device and a receiver wirelessly associated with the transmitter, such that the transmitter and receiver wirelessly transmit the temperature readings taken by the temperature sensing device from the transmitter to the receiver. The system also including a control unit operatively connected to the receiver that is configured to receive the transmitted temperature readings and determine when the transmitted temperature readings exceed a predefined temperature setpoint.
    Type: Grant
    Filed: May 19, 2011
    Date of Patent: March 24, 2015
    Assignee: Gillespie + Powers, Inc.
    Inventors: John M. Peterman, Mark A. Roberts
  • Patent number: 8764435
    Abstract: A modulating furnace having a variable rate burner and a controller is operated at a first burner firing rate for a first period of time, and a higher burner firing rate once the first period of time has expired. In some instances, the burner may be operated only while the controller is receiving a call for heat from a thermostat or the like.
    Type: Grant
    Filed: February 1, 2012
    Date of Patent: July 1, 2014
    Assignee: Honeywell International Inc.
    Inventors: Timothy J. Nordberg, Brent Chian, Michael W. Schultz, Douglas D. Bird
  • Publication number: 20130161402
    Abstract: A method of preventing exhaust gas from leaking out of a drying furnace is disclosed. In the method, the temperature of an exhaust passage and the temperature of a heater are measured, and turning on/off the heater is controlled in response to the measured temperatures. The present invention can be applied to all kinds of apparatuses having drying furnaces which are heated by heaters and thus generate the exhaust gas and can effectively prevent exhaust gas from leaking out of the apparatuses. Furthermore, the present invention can be more effectively applied to food waste disposers which heat food waste containing a large amount of water. In particular, the present invention is effective for circulation food waste disposers in which exhaust gas is condensed and re-supplied into a drying furnace as recirculation gas.
    Type: Application
    Filed: June 16, 2011
    Publication date: June 27, 2013
    Applicant: COWAY CO., LTD.
    Inventors: Myung Jin Park, Byoung Chan Bae, Tae Seok Shin
  • Patent number: 8201750
    Abstract: An electronic circuit for a hot water heating system an override thermostat; a timer operable to deactivate and reactivate the burner while a room thermostat is calling for heat; a differential temperature switch configured to disconnect the electrical supply to the water pump when the difference in temperature between the water at the boiler inlet and the water at the boiler outlet falls below an adjustable set point; and, a temperature switch configured to prevent operability of the timer until the temperature of the water at the burner outlet rises above an adjustable set point.
    Type: Grant
    Filed: July 24, 2009
    Date of Patent: June 19, 2012
    Inventor: James Edward Sambrook
  • Patent number: 8123518
    Abstract: A modulating furnace having a variable rate burner and a controller is operated at a first burner firing rate for a first period of time, and a higher burner firing rate once the first period of time has expired. In some instances, the burner may be operated only while the controller is receiving a call for heat from a thermostat or the like.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: February 28, 2012
    Assignee: Honeywell International Inc.
    Inventors: Timothy J. Nordberg, Brent Chiain, Michael W. Schultz, Douglas D. Bird
  • Publication number: 20110269082
    Abstract: Systems, methods, and controllers for controlling gas-fired appliances such as warm air furnaces are disclosed. An illustrative furnace system can include a burner unit in communication with a combustion air flow conduit and heat exchanger, a variable speed inducer fan or blower adapted to provide a flow of combustion air to the burner unit, a furnace controller and motor speed control unit adapted to regulate the speed of the inducer fan or blower, and a pneumatically modulated gas valve adapted to variably output gas pressure to the burner unit based at least in part on the combustion air flow.
    Type: Application
    Filed: July 7, 2011
    Publication date: November 3, 2011
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventor: Michael W. Schultz
  • Patent number: 7870854
    Abstract: An exemplary heating system can be configured with a control system configured for controlling the heating system to reduce inefficiencies, and/or allow the heating system to operate in a relatively optimum manner. In accordance with an exemplary embodiment, a closed-loop control system may be configured to control various portions of the heating system based, at least in part, upon signals and/or information received from various sensors of the heating system. For example, among various other types of information provided within a closed-loop feedback, control may be configured based upon the pressure within the combustion chamber. In accordance with another exemplary embodiment, the closed-loop control system may determine a portion of the heating system is not operating properly, based at least in part upon feedback from one or more sensors configured within the heating system.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: January 18, 2011
    Assignee: FPI Fireplace Products International Ltd
    Inventors: George H. K. Lau, Robert A. Little, Gordon Arthur Lloyd Coutts, Davinder Gopal Lal, Chi Ming Gavin Tham
  • Publication number: 20100122806
    Abstract: Compact and efficient apparatuses for transferring heat, heat exchangers, and furnaces, as well as HVAC units, HVAC systems, and buildings therewith, plus methods of making such devices. Furnace heat exchangers, for example, have an added stage, added in an unconventional way, that improves efficiency without unduly increasing size, while maintaining required radiuses of bends in tubing. Various embodiments orient bends at particular angles to allow stages to fit together more closely, provide improved structure for connecting stages using two collectors that seal against a common junction plate, provide for indoor air passing through the heat exchanger to pass through different passes of the heat exchanger in an unconventional order in order to provide greater compactness, or a combination thereof, as examples.
    Type: Application
    Filed: November 14, 2008
    Publication date: May 20, 2010
    Applicant: Nordyne Inc.
    Inventor: Linda M. Halgash
  • Patent number: 7575178
    Abstract: An apparatus for extracting heat from a heat source comprising a housing having a first end with a first opening and a second end with a second opening. The housing includes an internal compartment therein and the first end of the housing is connected to said heat source. A channel extends from the housing for providing access to the internal compartment. A hollow conduit is positioned within the internal compartment extending between the first opening and the second opening. A plurality of members are positioned on an exterior surface of the conduit and along the length thereof. The members are able to absorb heat from within the conduit and release the absorbed heat into the internal compartment creating heated air. The apparatus includes a means for drawing air through and expelling air from said conduit and means for moving said heated air out from said internal compartment to a second compartment. The apparatus is activated via means connected to each of the drawing means and the moving means.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: August 18, 2009
    Inventors: Kim Loewen, Gina Gaida
  • Publication number: 20090127346
    Abstract: A method for effecting cooperation between a modulating air conditioning system and a two-stage thermostat for satisfying an air conditioning load demand in a conditioned space includes: (a) operating the thermostat in a plurality of succeeding operating cycles to issue a first call signal or a second call signal indicating a first or second stage operation by the air conditioning system; the first and second stage operation being effected according to a first operating regimen to satisfy the air conditioning load demand; (b) operating the air conditioning system in response to the first and second call signals; the air conditioning system operating at a first power level when receiving the first call signal and operating at a predetermined second power level when receiving the second call signal; the first power level being established by the air conditioning system according a second operating regimen.
    Type: Application
    Filed: November 21, 2007
    Publication date: May 21, 2009
    Applicant: Lennox Manufacturing, Inc., a Corporation of Delaware
    Inventor: Wojciech Grohman
  • Patent number: 7385863
    Abstract: A semiconductor memory device enabling efficient repair of defects by using limited redundant memory while suppressing a drop of access speed accompanied with the repair of defects of the memory, wherein a first memory array is divided into a plurality of memory regions for each 16 word lines and wherein defective memory addresses in regions are stored in a second memory array. When a memory address for accessing the first memory array is input, the defective memory address of the memory region including the memory to be accessed is read out from the second memory array. In this way, the addresses of defective memory in 16 word lines worth of a memory region are stored in the second memory array 2, therefore addresses of a wider range of defective memory can be stored. For this reason, it becomes possible to repair defects occurring at random efficiently.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: June 10, 2008
    Assignee: Sony Corporation
    Inventors: Toshiyuki Nishihara, Yoshio Sakai
  • Publication number: 20080124667
    Abstract: Systems, methods, and controllers for controlling gas-fired appliances such as warm air furnaces are disclosed. An illustrative furnace system can include a burner unit in communication with a combustion air flow conduit and heat exchanger, a variable speed inducer fan or blower adapted to provide a flow of combustion air to the burner unit, a furnace controller and motor speed control unit adapted to regulate the speed of the inducer fan or blower, and a pneumatically modulated gas valve adapted to variably output gas pressure to the burner unit based at least in part on the combustion air flow.
    Type: Application
    Filed: October 18, 2006
    Publication date: May 29, 2008
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventor: Michael W. Schultz
  • Patent number: 7296426
    Abstract: An interactive system for controlling the operation of an HVAC system is provide that comprises a thermostat for initiating the operation of the HVAC system in either a full capacity mode of operation or at least one reduced capacity mode of operation, and a controller for an outside condenser unit having a condenser fan motor and a compressor motor, the controller being capable of operating the compressor in a full capacity mode and at least one reduced capacity mode. The system also comprises a controller for an indoor blower unit having a blower fan motor, the controller being capable of operating the blower fan motor in a full capacity mode an at least one reduced capacity mode. The system further includes a communication means for transmitting information between the outside condenser unit controller and at least the indoor blower controller, where the information relates to the operation of the indoor blower and the outdoor condenser unit.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: November 20, 2007
    Assignee: Emerson Electric Co.
    Inventors: William P. Butler, Steven L. Carey, Hung Pham, Nagaraj Jayanth
  • Patent number: 6886754
    Abstract: A thermostat is operable from battery, common-wire (“C-wire”), or furnace relay power. The thermostat includes a power source selector, such as a jumper wire, that is set when the thermostat is installed in a heating system. In a gas millivolt heating system, the thermostat operates off of battery power. In heating systems having a C-wire, a diode bridge converter converts alternating-current voltage to direct-current voltage to provide operating power to the thermostat. In heating systems without a C-wire and having sufficient furnace relay current, a triac converter in series with the furnace relay provides voltage spikes to the diode bridge converter to provide operating power to the thermostat when the furnace is on, and the diode bridge converts AC to DC voltage when the furnace is not on. The thermostat can also be used in cooling systems and heating, ventilation, and air-conditioning systems. Thus, the thermostat can be used in a wide variety of applications.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: May 3, 2005
    Assignee: Tim Simon, Inc.
    Inventors: Blaine M. Smith, Timothy M. Simon
  • Publication number: 20040245349
    Abstract: A thermostat is operable from battery, common-wire (“C-wire”), or furnace relay power. The thermostat includes a power source selector, such as a jumper wire, that is set when the thermostat is installed in a heating system. In a gas millivolt heating system, the thermostat operates off of battery power. In heating systems having a C-wire, a diode bridge converter converts alternating-current voltage to direct-current voltage to provide operating power to the thermostat. In heating systems without a C-wire and having sufficient furnace relay current, a triac converter in series with the furnace relay provides voltage spikes to the diode bridge converter to provide operating power to the thermostat when the furnace is on, and the diode bridge converts AC to DC voltage when the furnace is not on. The thermostat can also be used in cooling systems and heating, ventilation, and air-conditioning systems. Thus, the thermostat can be used in a wide variety of applications.
    Type: Application
    Filed: June 3, 2003
    Publication date: December 9, 2004
    Applicant: Tim Simon, Inc., a corporation of the State of California
    Inventor: Blaine M. Smith
  • Publication number: 20040104276
    Abstract: The present invention provides a system and single controller for receiving constant and individualized information from a plurality of air control systems. A single controller is capable of controlling and interacting with at least two separate air control systems to control an environmental characteristic, and in the process, reduces the costs associated with the manufacturing and every day operation of the individual systems. In addition, the controller is capable of intelligently communicating with the input and output devices of the system, and particularly with each individually interfaced appliance, such that the controller can adaptively control the system through the use of stored historical data.
    Type: Application
    Filed: September 25, 2003
    Publication date: June 3, 2004
    Applicant: Tjernlund Products, Inc.
    Inventors: John R. Weimer, Timothy G. Hoyez
  • Patent number: 6637667
    Abstract: Control apparatus for an environmental control system comprises input circuitry receiving environmental information and output circuitry for controlling an HVAC system. Processing circuitry in the controller configures the output circuitry based at least in part on the signals received on the input circuitry. Information about the status of the HVAC system may be transferred to system administrators using a wireless link.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: October 28, 2003
    Assignee: Pentech Solutions, Inc.
    Inventors: Dale A. Gauthier, Guy D. Covert
  • Publication number: 20030192952
    Abstract: A system for heating and cooling the interior of a motor vehicle is provided which includes a first climate control device designed to heat or cool a front area of the interior, a second climate control device designed to heat or cool a rear area of the interior, a first evaporator connectable to a first cooling agent circuit assigned to the first climate control device and a second evaporator connectable to a second cooling agent circuit assigned to the second climate control device. The second evaporator is located in a latent storage in order to charge the latent storage with cold and the second climate control device contains a first heat exchanger designed to transfer the cold removed via a heat transfer medium circuit or the second cooling agent circuit from the latent storage for cooling the rear area of the interior by an air flow.
    Type: Application
    Filed: April 1, 2003
    Publication date: October 16, 2003
    Applicant: Webasto Thermosysteme International GmbH
    Inventors: Oliver Horn, Noureddine Khelifa, Steffen Korfmann
  • Patent number: 6609904
    Abstract: A gas furnace control arrangement includes a control unit control unit and an operating unit adapted to control the control unit, the control unit having a valve seat holding a set of solenoid valves, the solenoid valves including a main valve for fuel gas input control, a mother flame valve adapted to control a gas passage from the valve seat to a mother flame nozzle, a high flow rate valve and a medium flow rate valve and a low flow rate valve adapted to control a respective gas passage from the valve seat to a main flame nozzle, the operating unit including a power switch adapted to switch on/off an electronic igniter and to close/open the main valve and the mother flame valve, a strong flame switch adapted to close/open the high flow rate valve, a medium flame switch adapted to close/open the medium flow rate valve, and a weak flame switch linked to the strong flame and the medium flame switch and adapted to close/open the low flow rate valve.
    Type: Grant
    Filed: January 3, 2001
    Date of Patent: August 26, 2003
    Inventor: Wen-Chou Chen
  • Patent number: 6360955
    Abstract: A space heater for the interior of a building has a support enclosure containing a gas burner and a gas conduit connecting the burner to a source of combustible gas. An electronically controlled proportional valve is located in the gas conduit. A fan and motor assembly are in the enclosure for distributing heated air from the burner when gas is communicated through the conduit and to the burner for combustion. A control system and a PC interface of a PC are located in the support enclosure to receive a data processing card having a predetermined temperature set point relating to temperature conditions within the building.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: March 26, 2002
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Steven J. Hoff, Jay D. Harmon, David Van Utrecht
  • Patent number: 6109531
    Abstract: A high reliability heating system that includes dual furnace control mechanisms wherein each furnace control mechanism includes blowers and control elements and each is independently operable to control the operation of a shared furnace burner unit and heat exchanger. The heating system preferably includes a controller mechanism selector mechanism that detects an abnormal operating condition, malfunction, in the controlling furnace controller mechanism and, in response, automatically switches control to the other furnace controller mechanism.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: August 29, 2000
    Inventor: Brien Hollis
  • Patent number: 5971284
    Abstract: A method and apparatus of regulating cycles of a burner in a forced air heating system. A control unit uses a sensor at an output of a heat exchanger to make measurements of a temperature of air output from the heat exchanger. The control unit observes temperature measurements, after the burner has turned on. It initializes a confirmation interval when two consecutive temperature measurements are the same. If the temperature is the same at an end of the confirmation interval. The invention interrupts firing of the burner for an interrupt interval. The interrupt interval is insufficient to allow the heat exchanger to cool below a temperature useful for heating below which the circulation fan would shut off.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: October 26, 1999
    Assignees: Intellidyne, LLC, Harvey Schwartz
    Inventor: Jack Hammer
  • Patent number: 5729474
    Abstract: To anticipate potential failure of a temperature modification device (e.g., heating, ventilating and air conditioning equipment used in a commercial building), an efficiency value representing the ability of the temperature modification device to change temperature in a predetermined zone is repeatedly computed. When one of these values is computed, it is used in determining whether the ability of the temperature modification device to change temperature in the predetermined zone has deteriorated over time. This is done by comparing a current efficiency value with a previous efficiency value. In response to a determined deterioration exceeding a predetermined tolerance, a control signal for initiating inspection of the temperature modification device is communicated, thereby enabling the device to be serviced in response to a detected operating condition of the device and before actual failure of the device.
    Type: Grant
    Filed: December 9, 1994
    Date of Patent: March 17, 1998
    Assignee: Excel Energy Technologies, Ltd.
    Inventors: Paul N. Hildebrand, W. John Light, T. Frank Knight, Kelley A. Lawrence
  • Patent number: 5666889
    Abstract: Furnace combustion in a multi-stage or variable input furnace is controlled by operating the furnace in a high fire mode at furnace start-up until the temperature of the products of combustion, or a temperature corresponding to the products of combustion, equals or exceeds a selected temperature. A temperature sensor, preferably a thermostat, is located downstream of the furnace zone of combustion (e.g., in a flue collector box at an outlet from the heat exchanger). The thermostat provides an indication of the products of combustion temperature and has a set point corresponding to the selected temperature. When the products of combustion temperature is less than the selected temperature, the thermostat contacts remain closed. The furnace is operated in the high fire mode while the thermostat contacts remain closed in response to a demand for heating, irrespective of whether the demand is for first stage or second stage heating.
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: September 16, 1997
    Assignee: Lennox Industries Inc.
    Inventors: Lance J. Evens, Michael E. Rose
  • Patent number: 5616995
    Abstract: Systems and methods for controlling a draft inducer for use with a furnace. The draft inducer includes a fan for moving combustion chamber gases for inducing a draft in the furnace combustion chamber that causes a pressure drop across a heat exchanger. The density of the gases flowing across the heat exchanger and the fan differs from a first operating state of the furnace to a second operating state of the furnace. A motor drives the fan in response to a motor control signal so that different motor speeds result as a function of the density of the gases flowing across the fan. A control circuit generates the motor control signal as a function of a first set of speed/torque curves until a speed signal indicates that the motor has reached a predetermined speed. After the speed signal indicates that the motor has reached the predetermined speed, the control circuit generates the motor control signal as a function of a second set of speed/torque curves.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: April 1, 1997
    Assignee: General Electric Company
    Inventor: Robert K. Hollenbeck
  • Patent number: 5522541
    Abstract: In a two-stage furnace system, including a thermostat, at least one gas burner with a low and high-fire operating capability, an inducer fan having low and high speed operating settings, and a high-fire pressure switch, a method for handling the high-fire pressure switch being in an inappropriately open condition. The method has the steps of: determining whether the thermostat is issuing a call for high heat and, if it is, determining if the high-fire pressure switch is open. If the high-fire pressure switch is open, waiting a predetermined time, determining if the high-fire pressure switch is still open and, if it is, completing a furnace shutdown procedure, then initiating a normal shutdown, then an ignition sequence in high-speed inducer pre-purge mode, determining if the high-fire pressure switch remains open, and if so, running at least one gas burner in low-fire mode. If, while these steps are being performed, the high-fire pressure switch closes, running the system in high-fire mode.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: June 4, 1996
    Assignee: Carrier Corporation
    Inventors: Ninev K. Zia, Daniel J. Dempsey, Hall Virgil, Jr.
  • Patent number: 5520327
    Abstract: An electronic thermostat having a safety feature includes a controller which sends control signals to circuitry used for activating a system for conditioning air. The control signals are used to control the active state of the system for conditioning air. Furthermore, safety cutoff circuitry is incorporated into the thermostat whereby the safety cutoff circuitry is used to override the control signal sent from the controller when a predetermined temperature is reached in the space being heated or cooled.
    Type: Grant
    Filed: September 23, 1994
    Date of Patent: May 28, 1996
    Assignee: Carrier Corporation
    Inventors: William O. Shreeve, Thomas W. Essig
  • Patent number: 5467920
    Abstract: An electromechanical thermostat has a fixed value voltage anticipator resistor and a variable anticipator resistor for series connection with the load. This allows a single thermostat to control either a high efficiency furnace requiring a relatively low cycle rate or a furnace of conventional efficiency which can function at a higher cycle rate. Preferably, the voltage anticipator resistor is selected to give the cycle rate required by high efficiency furnaces when the resistance of the variable anticipator resistor is set to zero ohms. If the thermostat is shipped with the variable resistor set to zero ohms, the installer will not have to adjust the variable resistor whenever the thermostat is installed in a system requiring that cycle rate.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: November 21, 1995
    Assignee: Honeywell Inc.
    Inventor: Richard B. Porter
  • Patent number: 5340028
    Abstract: A method for providing a low fire mode and a high fire mode of a heating cycle in a current cycle of a furnace as a function of the previous heating cycle wherein the current heating cycle is a function exclusively of time run in low fire mode and time run in high fire mode of the previous heating cycle, comprising the steps of: (1) determining the existence of a heating load to be satisfied; (2) running burners in low fire mode for a first time interval that does not exceed a predetermined limit, L.sub.des ; (3) running the burners in high fire mode for a second time interval until the heating load is satisfied; (4) calculating a BtU load requirement, as a function of the first time interval and the second time interval; and (5) determining the desired low fire mode time limit, L.sub.des, for the next cycle from the calculated BtU load requirement.
    Type: Grant
    Filed: July 12, 1993
    Date of Patent: August 23, 1994
    Assignee: Carrier Corporation
    Inventor: Kevin D. Thompson
  • Patent number: 5337952
    Abstract: In a heating system containing twinned furnaces capable of independently operating at multiple levels, a method for providing multiple heating modes to satisfy a required heating load during a given cycle, there being some total number of heating modes, wherein each heating mode may be activated for a time interval whose length is a function of furnace activity during the most recent previous cycle.
    Type: Grant
    Filed: July 28, 1993
    Date of Patent: August 16, 1994
    Assignee: Carrier Corporation
    Inventor: Kevin D. Thompson
  • Patent number: 5226590
    Abstract: An adaptor is designed to mount a duty cycling control switch for a furnace or air conditioning system which has flexible duct work. The adaptor includes two opposite cylindrical sections with a central section which includes an arcuate portion and a planar rectangular portion. The planar rectangular portion is tangential to the surfaces of the first and second cylindrical sections. The duty cycling control switch is mounted to this planar portion. Thus, air passing through the duct work will pass through this adaptor altering the temperature of the rectangular plate, thus, altering the temperature of the duty cycling switch causing it to activate.
    Type: Grant
    Filed: January 15, 1992
    Date of Patent: July 13, 1993
    Assignee: Raymond K. Davis
    Inventor: Raymond K. Davis
  • Patent number: 5092518
    Abstract: Provided is a hot-air type heater including a heat generating means such as a burner heater from which hot air is produced and blown out the heater into a living room so as to warm up the inside of the room with a uniform temperature distribution even among various heating rate conditions. The hot-air heater includes at least of variable angle louvers which are vertically swingable, and a control means for swinging the louver in association with at least either a hot air flow rate at a hot air outlet opening of the heater or the heating value of the heat generating means, so that the louver is vertically swung in accordance with an output from the control means in order to minimize differences in temperature distribution in the room during operation of the heater under various heating conditions.
    Type: Grant
    Filed: May 10, 1989
    Date of Patent: March 3, 1992
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mituharu Tomioka, Tadashi Yamazaki, Hiroo Oshima, Hajime Satoda, Mitsuhiro Imajima
  • Patent number: 4896828
    Abstract: An emergency heat circuit for a microprocessor-controlled furnace has a first emergency heat switch with one terminal in contact with a rectifier circuit that provides a DC voltage when the thermostat calls for heat, and another terminal connected to an emergency heat-active input of the microprocessor. A first opto-isolator has an optical actuator, such as an LED connected to the microprocessor failure output and a switched element unless such as a photo-transistor, with terminals connected in parallel to the first emergency heat switch. A second opto-isolator is also connected to the emergency heat switch and has an AC photo-actuated switch element, such as a photo-triac, connected, for example, to the W conductor and with an output connected to the rectifier circuit. The photo-triac latches on until the thermostat is satisfied.
    Type: Grant
    Filed: June 23, 1989
    Date of Patent: January 30, 1990
    Assignee: Carrier Corporation
    Inventor: Robert W. Peitz, Jr.
  • Patent number: 4887767
    Abstract: A two-stage gas furnace control system automatically shifts into a high fire only mode if, in two consecutive low fire heating cycles a limit switch is tripped to indicate that a gas valve is stuck in a high fire condition. In this way, continued operation is allowed to proceed in a safe manner. Provision is also made to lock out the system from further operation if, while in the high fire only mode, the limit switch is tripped in a predetermined consecutive number of cycles or if, while in a preemptive low fire only mode, the limit switch is tripped.
    Type: Grant
    Filed: October 21, 1988
    Date of Patent: December 19, 1989
    Assignee: Carrier Corporation
    Inventors: Kevin D. Thompson, Gary W. Ballard
  • Patent number: 4817862
    Abstract: Control apparatus for controlling the operation of a gas valve in a gas heating system which includes thermostatic switch means and a source of AC voltage which are connected to form a series circuit with the gas valve is disclosed. The control apparatus comprises switch means which is connected to provide continuity in the series circuit upon receipt of a first control signal and to remove the continuity in the series circuit upon removal of the first control signal. Isolation means receives a second control signal having a high state and an alternate low state and generates the first control signal when receiving the high state of the second control signal. A power supply receives the AC voltage when the thermostatic switch means is closed and provides a DC voltage to a timer means. The timer means then generates the second control signal.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: April 4, 1989
    Assignee: Trans-Tech Industries, Inc.
    Inventor: Amor Bhattacharya
  • Patent number: 4712733
    Abstract: A heating system and air conditioning system incorporating a duty cycling control switch are disclosed. The duty cycling control switch for either the furnace or air conditioning system is mounted within the supply side duct of the system, i.e., the hot air duct for a furnace or cold air duct for an air conditioner. The duty cycling control is a bi-metal switch totally enclosed within a case having a metal base whereby the heat from the air in the duct contacts the metal base which is transferred to a bi-metallic element which in turn opens or closes a switch. This makes the switch particularly responsive to gradual changes in the temperature of the output air but prevents the duty cycling switch from responding to rapid fluctuations of air temperature within the duct.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: December 15, 1987
    Inventor: Raymond K. Davis
  • Patent number: 4706881
    Abstract: A self-correcting control system and method is provided for a furnace to correct certain operating conditions that exceed normal limits. Upon sensing insufficient air flow as a function of the pressure drop across the heat exchangers, the control system and method cause the inducer motor to increase in speed, thereby to increase the flow of combustion air. Similarly, upon sensing that the flow of air to be heated exceeds a predetermined temperature, the control system and method will increase the speed of the air blower to increase the flow rate of air to be heated through the furnace, thereby resulting in lowering the temperature of the air to be heated below the predetermined temperature. Upon sensing a gas flow leak through the gas regulator, the control system and method will recycle the gas regulator to properly seat a gas flow control valve therein. If none of the self-correcting features correct the particular occurring problem, the control system and method will shut down the furnace.
    Type: Grant
    Filed: November 26, 1985
    Date of Patent: November 17, 1987
    Assignee: Carrier Corporation
    Inventor: Gary W. Ballard
  • Patent number: 4698574
    Abstract: When an output from a sensor (11) is decreased below a key-lock release preset value (K), a comparator (19) generates an output so as to reset a flip-flop (21) and to enable an AND gate (22). When the output from the sensor (11) is decreased below a reset preset value (R), a comparator (20) generates an output so as to supply a reset signal to an integrated value holding unit (16) through the AND gate (22) and to reset the flip-flop (21), thus thereafter restarting an integral action by the integrated value holding unit (16).
    Type: Grant
    Filed: October 23, 1985
    Date of Patent: October 6, 1987
    Assignee: Yoshiki Industrial Co., Ltd.
    Inventors: Yasuo Yoshizawa, Masatoshi Jinno
  • Patent number: 4676433
    Abstract: A regulating arrangement intended for supplying heat to a confined space, including a heating source (13), a regulating means (12) intended for regulated heat supply from the heating source, a device for detecting one or a plurality of measurement values and connected (12a, 12b) to the regulating means, which in dependence on received measurement values regulates the amount of heat delivered by the heating source. The regulating means (12) is controlled (10b) by a device arranged to detect the actual heating requirement of the ventilation air at that moment in time, or for detecting a part of this heat requirement.There is also provided an arrangement or a device for establishing when the requirement to heat an air mass to achieve a pre-determined temperature increase exceeds a pre-determined heating requirement and by how much, by causing the air mass an energy delivering means (4) and establishing the energy taken-up by the air mass and the heat content of the mass at that moment in time.
    Type: Grant
    Filed: March 26, 1985
    Date of Patent: June 30, 1987
    Assignee: Tyrens Foretagsgrupp AB
    Inventors: Sune Haggbom, Per O. Nylund, Arne Lind
  • Patent number: 4667874
    Abstract: An auxiliary heating/cooling system controller is connected in series between the household thermostat and the furnace burner valve and compressor. The controller includes a timing control which is responsive to a preset time interval valve and the plenum temperature to cycle the furnace burner on and off in order to moderate the temperature of the furnace heat exchanger, thus improving furnace efficiency. Upon installation the controller is programmed with a digital valve corresponding to the delay between a call for heat from the household thermostat and the initiation of the furnace fan. This value is then used to set a timer in the controller which synchronizes the initiation of the duty cycle control of the burner to the start of the fan at the beginning of a heating cycle, and to control the cycle time of the burner. A plenum thermostat monitors the temperature of the air produced by the furnace and if the air exceeds a predetermined limit the OFF time of the burner is increased.
    Type: Grant
    Filed: July 23, 1985
    Date of Patent: May 26, 1987
    Assignee: Harold R. Johnson
    Inventors: Harold R. Johnson, Steven E. Lombardi
  • Patent number: 4664311
    Abstract: A temperature sensitive duty cycling control switch is mounted to a forced air ductless gas or oil heater by a special mounting bracket. The bracket attaches to the front of the heater in the path of the heated airflow. The mounting device is basically a tapered conduit or duct which is held at a distance from the heater so that it does not unduly obstruct the airflow and is tapered to concentrate air generated by the heater onto a plate mounted in front of the duct. The duty cycling control switch is then mounted to this plate and responds to the temperature of the plate. This enables the cycling of the heater burner while the fan continues to operate.
    Type: Grant
    Filed: August 29, 1985
    Date of Patent: May 12, 1987
    Assignee: Duty Cycle, Inc.
    Inventor: Dean Welch
  • Patent number: 4646962
    Abstract: Damper means having rotatable closure means mounted in a housing placed in the flow stream of a heating/cooling medium to regulate and control the medium being transported through duct means of a heating/cooling device; said closure means being operated by motor means, said motor means and fuel control means of the heating/cooling device being energized by means of a coded signal of thermostatically operated generator/transmitter means, said signal being transmitted along existing wires of a structure to receiver means, said receiver means electrically connecting to said motor means and to fuel control means, demodulating said coded signal and operating said motor means and fuel control means.
    Type: Grant
    Filed: October 1, 1985
    Date of Patent: March 3, 1987
    Inventor: Willie T. Grant
  • Patent number: 4638942
    Abstract: An adaptive microprocessor control system and method provide a low heat mode and a high heat mode of a heating cycle in a furnace dependent upon the performance of the previous heating cycle. The duration of the low heat mode and subsequent high heat mode period is a function of the previous low heat mode duration, previous high heat mode duration, and the time period between the end of the previous heating cycle and the beginning of the next heating cycle. The control and method utilize a single-stage thermostat for providing the dual rates of heating.
    Type: Grant
    Filed: December 2, 1985
    Date of Patent: January 27, 1987
    Assignee: Carrier Corporation
    Inventors: Gary W. Ballard, Robert M. Mamot
  • Patent number: 4632303
    Abstract: An electronic thermostat utilizing a switched power supply which operates either from a voltage appearing across an open circuit at a heater or air conditioner activation circuit (de-energized state) or from a current flowing in the activation circuit upon short circuiting (energized state) of the activation circuit. The power supply provides an uninterrupted source of power to the electronic thermostat which controls the source of input power to the power supply in addition to the state of the activation circuit. The electronic circuit implements a piecewise linear, with hysteresis loop discontinuity, control function.
    Type: Grant
    Filed: October 25, 1985
    Date of Patent: December 30, 1986
    Inventor: John N. Rodittis
  • Patent number: 4629113
    Abstract: A device for augmenting the control of a forced air furnace includes a heat probe which is located in association with a furnace heat exchanger so as to sense the air temperature of air passing across the heat exchanger. The probe is connected via a buffer to an optical controlled switch. A latch is associated with both the probe and the switch such that in response to a high temperature turn off point the optical coupled switch shuts off the furnace solenoid associated with the furnace and maintains the solenoid in an off position until the probe senses a low temperature turn on point. Upon sensing the low temperature turn on point the solenoid is turned back on and is maintained in the on position by the latch until the high temperature point is again reached.
    Type: Grant
    Filed: October 5, 1984
    Date of Patent: December 16, 1986
    Assignee: RHR, Inc.
    Inventors: Randy L. Brandt, K. Herb Boswell, Robert A. Pett
  • Patent number: 4541561
    Abstract: The heating equipment includes an auxiliary heating apparatus having a space heater mounted within an air recirculating furnace system for heating air therein. A thermostat responds to a first predetermined ambient temperature to activate the space heater for heating air within the furnace system. A conduit, connected electrically between the output of the thermostat and the air recirculating blower of the furnace system, sends an electrical signal to the blower to activate it when the thermostat is energized upon the ambient temperature falling below the first predetermined temperature.
    Type: Grant
    Filed: June 23, 1983
    Date of Patent: September 17, 1985
    Inventor: Robert E. Smith
  • Patent number: 4477019
    Abstract: A flue gas heat recovery apparatus for a forced air type furnace of the type having a furnace heat exchanger, a return air duct and a heated air duct, and a blower for passing air from the return air duct over the furnace heat exchanger to the heated air duct. The heat recovery apparatus includes a secondary heat exchanger mounted in the return air duct having its inlet connected to the outlet of the furnace heat exchanger and an induced draft fan having its inlet connected to the outlet of the secondary heat exchanger and its outlet connected through an outlet flue pipe to the chimney. A vane is mounted in the outlet flue pipe in the path of flow from the induced draft fan and is moved between a closed position when the fan is not operating, to an open position when the fan is operating, and a switch is operated by the vane to operate the burner control after the induced draft is in operation.
    Type: Grant
    Filed: September 6, 1983
    Date of Patent: October 16, 1984
    Inventor: Johnnie J. Breitbach