Valves, Pressure Sensing Devices, and Controllers for Heating Appliances

Abstract

A valve apparatus includes substantially co-aligned first and second valve seats and substantially co-aligned first and second valve members. The first valve member is moveable relative to the first valve seat between at least an open position in which the first valve member is spaced from the first valve seat and a closed position in which the first valve member is seated against the first valve seat. The second valve member is moveable relative to the second valve seat between at least an open position in which the second valve member is spaced from the second valve seat and a closed position in which the second valve member is seated against the second valve seat. An armature is operable for moving the first and second valve members, in response to a magnetic field generated by a coil.

1 . A pressure sensing apparatus for sensing a gas pressure within a gas appliance, the pressure sensing apparatus comprising:
 a diaphragm moveable in response to changes in pressure acting against the diaphragm;   a light emitter;   a light sensing device; and   a light attenuator coupled to the diaphragm such that the light attenuator is moveable by the diaphragm between the light emitter and the light sensing device in response to changes in pressure acting against the diaphragm, the light attenuator configured to attenuate or vary the amount of light transmitted to the light sensing device from the light emitter as the light attenuator is moved therebetween by the diaphragm in response to changes in pressure;   whereby the light sensing device is operable to responsively provide a voltage output commensurate with the amount of light sensed by the light sensing device, which voltage output is indicative of a sensed pressure acting against the diaphragm.   
     
     
         2 . The pressure sensing apparatus of  claim 1 , wherein:
 the light attenuator has a variable thickness configured to reduce the amount of incident light transmitted through the light attenuator as a function of thickness of the light attenuator; and/or   the light attenuator is comprised of a material that possesses sufficient light permeability to allow some incident light to be transmitted through the light attenuator, and sufficient opacity to impede light transmission so as to reduce the amount of light transmitted through the light attenuator as a function of the thickness of the light attenuator; and/or   the diaphragm has first and second sides, the first side being in fluid communication with a pressurized volume in a valve apparatus such that the diaphragm is moveable in response to changes in fluid pressure acting against the first side of the diaphragm; and/or   the light attenuator is disposed on a pin biased by a spring against the second side of the diaphragm such that changes in pressure acting against the first side cause the diaphragm to move the light attenuator up and down; and/or   the light emitter and the light sensing device are aligned with and spaced apart from one another, such that the light emitter is directed at the light sensing device; and/or   a width of the light attenuator gradually tapers over its length to provide a sufficient thickness gradient to enable detection of incremental changes in the amount of attenuation by the light attenuator over its length; and/or   the light sensing device of the pressure sensor is configured to provide a voltage output that changes from a substantially maximum voltage output to a fractional voltage output upon detecting that the light attenuator has moved from a position in which the light attenuator is not between the light emitter and the light sensing device to a position in which a portion of the light attenuator is between the light emitter and the light sensing device, and wherein the light sensing device is configured to subsequently provide a voltage output that enables calibration of the present voltage output of the light sensing device with the actual known position of the light attenuator relative to the light sensing device.   
     
     
         3 . A valve apparatus including the pressure sensing apparatus of  claim 1 , the valve apparatus further including a valve seat, a coil, and a valve member moveable relative to the valve seat in response to an input voltage applied to the coil, wherein input voltage to the coil is controlled based on the voltage output of the light sensing device that is indicative of sensed pressure, to thereby adjust an opening between the valve member and the valve seat to achieve a desired outlet pressure. 
     
     
         4 . The valve apparatus of  claim 3 , wherein:
 the diaphragm is disposed within a housing separate from the valve apparatus and in communication with an outlet of the valve apparatus; and/or   a controller is coupled to the pressure sensing apparatus and the coil, wherein the controller is configured to determine a sensed pressure from the voltage output of the light sensing device, and to adjust the application of input voltage to the coil based on the sensed pressure, to thereby adjust the opening area between the valve member and the valve seat to achieve a desired outlet pressure; and/or   the controller is part of a furnace control that is not disposed on the valve apparatus; and/or   the varying voltage output of the pressure sensing apparatus as a function of the motion of the light attenuator, in response to changes in pressure acting against the diaphragm, is used to control the valve apparatus to regulate the output of the valve apparatus.   
     
     
         5 . A pressure sensing apparatus for sensing a gas pressure within a gas appliance, the pressure sensing apparatus comprising:
 a diaphragm moveable in response to changes in pressure acting against the diaphragm;   a first light emitter;   a second light emitter;   a first light sensing device;   a second light sensing device; and   a light interrupter coupled to the diaphragm such that the light interrupter is moveable by the diaphragm between the first light emitter and the first light sensing device when the diaphragm is exposed to a first pressure acting against the diaphragm and such that the light interrupter is moveable by the diaphragm between the second light emitter and the second light sensing device when the diaphragm is exposed to a second pressure acting against the diaphragm;   whereby a desired pressure of a valve apparatus can be established by interpolating between first and second positions at which the light interrupter is detected by the first and second light sensing devices corresponding to the first and second pressures.   
     
     
         6 . The pressure sensing apparatus of  claim 5 , wherein:
 the diaphragm has first and second sides, the first side being in fluid communication with a pressurized volume in a valve apparatus such that the diaphragm is moveable in response to changes in fluid pressure acting against the first side of the diaphragm; and/or   the light interrupter is configured to substantially impede transmission of light therethrough, and is disposed on a pin that is biased by a spring against the diaphragm such that an increase or decrease in pressure acting against the diaphragm causes the diaphragm to raise or lower the pin and light interrupter, respectively; and/or   the desired pressure is a pressure level that is above the first pressure and below the second pressure; and/or   the first pressure is below a rated outlet pressure for the valve apparatus and the second pressure is above the rated outlet pressure; and/or   the first light emitter and first light sensing device are preferably aligned with and spaced apart from one another, such that the first light emitter is directed at the first light sensing device; and/or   the second light emitter and the second light sensing device are located above the first light emitter and the first light sensing device.   
     
     
         7 . A valve apparatus including the pressure sensing apparatus of  claim 5 , the valve apparatus further including a valve seat, a coil, and a valve member moveable relative to the valve seat in response to an input voltage applied to the coil, wherein input voltage to the coil is determined by interpolating between first and second input voltages for establishing first and second positions of the valve member at which the light interrupter is detected by the first and second light sensing devices corresponding to the respective first and second pressures, whereby a desired pressure of the valve apparatus can be established. 
     
     
         8 . The valve apparatus of  claim 7 , wherein:
 the diaphragm is disposed within a housing separate from the valve apparatus and in communication with an outlet of the valve apparatus; and/or   a controller is coupled to the pressure sensing apparatus and the coil, wherein the controller is configured to adjust the application of input voltage to the coil by interpolating between first and second input voltages at which the light interrupter is detected by the first and second light sensing devices corresponding to the respective first and second pressure; and/or   the controller is part of a furnace control that is not disposed on the valve apparatus.   
     
     
         9 . A pressure sensing apparatus for sensing a gas pressure within a gas appliance, the pressure sensing apparatus comprising:
 a diaphragm moveable in response to changes in pressure acting against the diaphragm;   a first switch;   a second switch; and   a trigger coupled to the diaphragm such that the trigger is moveable by the diaphragm to actuate the first switch when the diaphragm is exposed to a first pressure acting against the diaphragm, and such that the trigger is moveable by the diaphragm to actuate the second switch when the diaphragm is exposed to a second pressure acting against the diaphragm;   whereby the first switch and the second switch device are operable to responsively provide an output that is indicative of sensed pressure at the first pressure and second pressure, respectively.   
     
     
         10 . The pressure sensing apparatus of  claim 9 , wherein:
 the second switch is positioned above the first switch such that the second switch is operable to detect the trigger when the diaphragm is exposed to the second pressure, which is higher than the first pressure; and/or   the first switch and the second switch are aligned with and spaced apart from one another, such that the trigger is raised and lowered between the first switch and the second switch; and/or   the diaphragm has first and second sides, the first side being in communication with an outlet of a valve apparatus such that the diaphragm is moveable in response to changes in outlet pressure acting against the first side; and/or   the trigger extends in a generally perpendicular direction from a pin that is disposed on the diaphragm, such that an increase or decrease in pressure acting against the diaphragm causes the diaphragm to raise or lower the trigger, respectively.   
     
     
         11 . A valve apparatus including the pressure sensing apparatus of  claim 9 , the valve apparatus further including a valve seat, a coil, and a valve member moveable relative to the valve seat in response to an input voltage applied to the coil, wherein input voltage to the coil is determined by interpolating between first and second input voltages for establishing first and second positions of the valve member at which the trigger actuates the first and second switches that correspond to the respective first and second pressures, whereby a desired outlet pressure of the valve apparatus can be established. 
     
     
         12 . The valve apparatus of  claim 11 , wherein:
 the desired pressure is a pressure level that is above the first pressure and below the second pressure; and/or   the first pressure is below a rated outlet pressure for the valve apparatus and the second pressure is above the rated outlet pressure for the valve apparatus; and/or   the diaphragm is disposed within a housing separate from the valve apparatus and in communication with an outlet of the valve apparatus; and/or   a controller is coupled to the pressure sensing apparatus and the coil, wherein the controller is configured to adjust the application of input voltage to the coil by interpolating between first and second input voltages at which the trigger actuates the first and second switches that correspond to the respective first and second pressures; and/or.   the controller is part of a furnace control that is not disposed on the valve apparatus.   
     
     
         13 . A pressure sensing apparatus for sensing a gas pressure within a gas appliance, the pressure sensing apparatus comprising:
 a diaphragm moveable in response to changes in pressure acting against the diaphragm; and   a transformer including a moveable core, the moveable core coupled to the diaphragm such that the moveable core is movable by the diaphragm to vary output of the transformer with changes in pressure acting against the diaphragm, whereby the transformer is operable for providing an output that varies with core movement, which is commensurate with changes in outlet pressure.   
     
     
         14 . A valve apparatus including the pressure sensing apparatus of  claim 13 , the valve apparatus further including a valve seat, a coil, and a valve member moveable relative to the valve seat in response to an input voltage applied to the coil, wherein input voltage to the coil is controlled based on the output of the transformer, to adjust an opening between the valve and the valve seat to attain a desired pressure. 
     
     
         15 . The valve apparatus of  claim 14 , wherein:
 the diaphragm has first and second sides, the first side being in communication with an outlet of the valve apparatus such that the diaphragm is moveable in response to changes in outlet pressure acting against the first side;   and/or the pressure sensing apparatus is not disposed on the valve apparatus;   and/or a controller is coupled to the pressure sensing apparatus and the coil, the controller is configured to determine a sensed pressure from the output of the transformer, and to adjust the application of input voltage to the coil based on the sensed pressure, to thereby adjust the opening area between the valve member and the valve seat to achieve a desired outlet pressure, and/or the controller is part of a furnace control that is not disposed on the valve apparatus.   
     
     
         16 . A system comprising:
 a pressure sensor configured to provide an output indicative of pressure at an outlet of a valve or within a pressurized volume in the valve; and   a controller in communication with the pressure sensor, the controller being configured to determine a sensed pressure from the output of the pressure sensor, and to responsively control or adjust the application of input voltage to a coil based on the sensed pressure, to thereby operate the coil to adjust an opening area between a valve member and a valve seat to achieve multiple, different desired pressures at the outlet of the valve while the valve is at least partially open.   
     
     
         17 . The system of  claim 16 , wherein:
 the system is operable for controlling a pressure in the pressurized volume in the valve; and   the pressure sensor provides an output indicative of the pressure within the pressurized volume in the valve.   
     
     
         18 . The system of  claim 16 , wherein:
 the system is operable for controlling operating capacity level of a variable capacity heating device; and   the system comprises a solenoid coil configured to generate a magnetic field in response to an input voltage to the solenoid coil, and to displace the valve member to vary the opening area between the valve member and the valve seat to adjust pressure at the outlet based on a magnitude of the magnetic field, wherein the magnitude of the magnetic field is dependent on the input voltage that is applied to the solenoid coil;   the pressure sensor is in communication with the outlet and configured to provide an output indicative of pressure at the outlet; and   the controller is configured to determine a sensed outlet pressure from the output of the pressure sensor, and to responsively control the application of input voltage to the solenoid coil based on the output of the pressure sensor indicative of pressure at the outlet, to thereby displace the valve member to adjust the opening area between the valve member and the valve seat to achieve multiple, different desired pressures at the outlet while the valve is at least partially open.   
     
     
         19 . The system of  claim 18 , wherein the controller comprises a microprocessor that includes a program that is configured to:
 generate a control signal for controlling application of input voltage that is applied to the solenoid coil for displacing the valve member for establishing a desired outlet pressure corresponding to a desired operating capacity level;   compare the output of the pressure sensor that is indicative of the pressure at the outlet to a reference associated with the desired operating capacity level, to determine an error amount relative to the reference;   determine a correction value associated with the control signal for the solenoid coil, for adjusting the displacement of the valve member to achieve the desired outlet pressure corresponding to a desired operating capacity level; and   generate a control signal for controlling application of input voltage that is applied to the solenoid coil for displacing the valve member based on the correction value, to displace the valve member to substantially achieve the desired outlet pressure corresponding to the desired operating capacity level.   
     
     
         20 . The system of  claim 18 , wherein:
 the control signal is a pulse width modulated signal having a duty cycle ratio of between 4 percent and 95 percent; and/or   the control signal is a pulse width modulated signal, in which a duty cycle that varies between 4 percent and 95 percent respectively corresponds to an operating capacity level that varies between 35 percent and 100 percent of the full operating capacity level of the heating device.