Patents by Inventor Rajendra Shah

Rajendra Shah has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20080097651
    Abstract: A method and control is provided wherein the sensors in a plurality of zones are properly associated with the dampers associated for each of the zones after installation. A technician goes to each zone and sends a signal from the sensor, and the control then makes a change at the associated damper. The technician can then ensure the two are properly associated within the control.
    Type: Application
    Filed: December 14, 2007
    Publication date: April 24, 2008
    Inventors: Rajendra Shah, Christopher Puranen
  • Publication number: 20070234746
    Abstract: A method to detect and respond to a coil condition in an HVAC system. The method includes calculating an initial airflow restriction value and a current airflow restriction value, which are compared. If the current airflow restriction value is greater than a first sum including the initial airflow restriction value and a first restriction factor, then a coil condition is preliminarily determined to be freezing and cooling in the HVAC system is stopped.
    Type: Application
    Filed: December 28, 2006
    Publication date: October 11, 2007
    Inventors: Chris Puranen, Rajendra Shah
  • Publication number: 20070186568
    Abstract: A refrigeration system is provided that includes a low voltage control circuit, a high voltage control circuit, a refrigeration system component, a contactor, a plurality of detection points, and a diagnostic device. The contactor is controlled by the low voltage control circuit to apply supply voltage from the high voltage control circuit to the refrigeration system component. The detection points are serially positioned with respect to one another within the low voltage control circuit and/or the high voltage control circuit. The diagnostic device has a plurality of indicator lights, where each indicator light is in electrical communication with a different one of the plurality of detection points.
    Type: Application
    Filed: January 19, 2007
    Publication date: August 16, 2007
    Inventor: Rajendra Shah
  • Publication number: 20070180838
    Abstract: The present invention relates generally to a method for automatically adjusting the interval of time between defrost cycles in a heat pump system. The method includes tracking the duration of the previous defrost cycle or cycles, and dynamically adjusting the length of time before initiating the next defrost cycle.
    Type: Application
    Filed: December 27, 2006
    Publication date: August 9, 2007
    Inventor: Rajendra Shah
  • Publication number: 20060153548
    Abstract: An electric heater is provided with an identifying resistor associated with a connection between the heater and a fan control. When the electric heater is connected to the control, the identifying resistor provides information with regard to the capacity of the particular electric heater that is being attached to the control. The control then utilizes this particular capacity to control both the electric heater and an associated fan motor.
    Type: Application
    Filed: March 3, 2006
    Publication date: July 13, 2006
    Inventors: Rajendra Shah, Eugene Mills, Jerry Ryan
  • Publication number: 20060058924
    Abstract: Static pressures are measured in an HVAC system and utilized to predict the condition of a filter in the HVAC system. As the filter becomes clogged, the static pressure can be expected to increase. Changes in the static pressure are determined periodically, and utilized to predict the condition of the filter. A display provides a user with an indication of the current condition of the filter, and a recommendation to replace the filter once it reaches a predetermined condition.
    Type: Application
    Filed: November 4, 2005
    Publication date: March 16, 2006
    Inventor: Rajendra Shah
  • Publication number: 20050207741
    Abstract: An electric heater is provided with an identifying resistor associated with a connection between the heater and a fan control. When the electric heater is connected to the control, the identifying resistor provides information with regard to the capacity of the particular electric heater that is being attached to the control. The control then utilizes this particular capacity to control both the electric heater and an associated fan motor.
    Type: Application
    Filed: December 19, 2003
    Publication date: September 22, 2005
    Applicant: CARRIER CORPORATION
    Inventors: Rajendra Shah, Eugene Mills, Jerry Ryan
  • Publication number: 20050195556
    Abstract: This invention describes here the alternate method of building multi-layer ceramic chip capacitors, known as MLCC capacitors. A method of building alternate layers of ceramic (dielectric) and metal conductive electrodes (FIG. 2) by using screen printer and screen-printing process. This invention suggests using only screen printers and screen printing process (no tape casting) to build MLCC capacitors. In the current MLCC capacitors manufacturing process, ceramic dielectric layer is formed by tape casting process and metal electrode layer is formed by screen printing (FIG. 1) process. In this invention, entire multi-layer structure consisting of ceramic dielectric layers and metal electrode layers are formed by screen printing process. In other words, using screen printer, screen-print ceramic dielectric layers on a substrate to the required thickness, with drying in between the layers. Next, on top of the dielectric layer, screen print electrode pattern and dry it.
    Type: Application
    Filed: March 5, 2005
    Publication date: September 8, 2005
    Inventor: Rajendra Shah
  • Publication number: 20050155362
    Abstract: Known psychometric characteristics of air are employed to achieve accurate indoor relative humidity control to prevent condensation inside a building envelope without complex mathematical computational requirements. An HVAC system control includes a simple control algorithm employed to calculate an effective delta (?T) based upon a single adjustment factor (A*) and environmental inputs. The effective delta (?T) is then used to determine a maximum allowable indoor relative humidity. The system control is then operable to selectively activate/deactivate a device to adjust an actual indoor relative humidity to a value less than the maximum allowable indoor relative humidity to prevent condensation inside the building envelope.
    Type: Application
    Filed: December 17, 2004
    Publication date: July 21, 2005
    Inventor: Rajendra Shah
  • Publication number: 20050159847
    Abstract: An HVAC system includes a portable controller unit which communicates with an indoor HVAC component and an outdoor HVAC component over a digital communication bus. A multiple of docking stations each in communication with the data bus are located at a multiple of locations throughout the system such that the portable controller unit may be selectively connected to any of the ports and moved therebetween. By moving the portable controller unit, the technician is then physically present at the HVAC component while exercising the system to obtain additional information and measurements directly from the HVAC component.
    Type: Application
    Filed: May 10, 2004
    Publication date: July 21, 2005
    Inventors: Rajendra Shah, Chris Puranen
  • Publication number: 20050156054
    Abstract: A multi-zoned HVAC system includes a control for independently determining the amount of airflow delivered to each zone within the HVAC system. The control determines nominal zone airflow and continuous fan airflow levels for each zone based upon a user selected fan airflow level and the relative size of each zone in the HVAC system. The control determines the desired system airflow for the entire system once the continuous fan airflow levels for each zone are determined. The HVAC system provides a continuous fan airflow to each zone independently of the continuous fan airflow delivered to any other zone and irrespective of the relative size difference of the zones.
    Type: Application
    Filed: October 19, 2004
    Publication date: July 21, 2005
    Inventor: Rajendra Shah
  • Publication number: 20050156050
    Abstract: A control is functional to perform a method of determining a maximum desired airflow for each of a plurality of zones in a multi-zone HVAC system, and an expected airflow to those zones. In part, these determinations are based upon an algorithm that calculates the relative size of the ducts leading to each of the zones. The expected and maximum airflows are compared for each of the zones, and if any zone has an expected airflow that exceeds its maximum airflow, certain steps are taken to reduce airflow to that zone.
    Type: Application
    Filed: July 13, 2004
    Publication date: July 21, 2005
    Inventors: Rajendra Shah, William VanOstrand, Laurie Werbowsky
  • Publication number: 20050155367
    Abstract: A control and method are disclosed to determine the relative duct sizes of a plurality of ducts leading to a plurality of zones in a multi-zone HVAC system. In a disclosed method, the dampers leading to each of the zones are operated such that one damper is held more open than the remaining dampers, and a system component is monitored as air is blown through the duct. In particular, a blower speed may be monitored. Once the blower speed is monitored, for one damper being open, with the remaining dampers being relatively closed, another damper is opened and the first is closed. This process continues until relative information is gathered for each of the zones. This relative information is then utilized to determine the relative sizes of the ducts leading to each of the zones as a percentage of the total duct size. The relative duct size information is then utilized to perform various control methods.
    Type: Application
    Filed: September 1, 2004
    Publication date: July 21, 2005
    Inventor: Rajendra Shah
  • Publication number: 20050155363
    Abstract: HVAC systems are employed to control the indoor environmental characteristics of a building structure to make it comfortable for its inhabitants. An HVAC system includes one single integrated central control to regulate an indoor temperature level, an indoor relative humidity level and an indoor fresh air level of a building structure during both a heating season and a cooling season. Further, the single integrated central control is operable to selectively activate/deactivate an indoor blower to control a sensible ratio within a building structure. In addition, a protection feature for avoiding condensation on the interior surfaces of the building structure is included as an user selectable option.
    Type: Application
    Filed: January 12, 2005
    Publication date: July 21, 2005
    Inventor: Rajendra Shah
  • Publication number: 20050159846
    Abstract: A HVAC system provides a central control which detects failed stage(s); removes the failed stage(s) from the staging sequence used by the controller; and later checks the failed stage periodically to see if the failed stage has become functional so that the no properly operational stage is returned to a staging sequence. The central control detects the failed stages and/or components by direct communication with the failed stages and/or components and/or by monitoring a temperature of a controlled area to determine if any particular stage is operating properly.
    Type: Application
    Filed: April 14, 2004
    Publication date: July 21, 2005
    Inventors: William Van Ostrand, Rajendra Shah
  • Publication number: 20050156049
    Abstract: A control for controlling a multi-zone HVAC system, wherein the heating or cooling equipment is operable in multiple stages, takes the demand on the system over time into account when determining an appropriate stage. In particular, a time integral of the system demands is utilized along with a current system demand to determine an appropriate stage. In this manner, a weakness in the prior art of allowing a long-term, small difference between the desired set point and the actual temperature in the various zones is addressed.
    Type: Application
    Filed: January 20, 2004
    Publication date: July 21, 2005
    Inventors: William Van Ostrand, Rajendra Shah, Lauric Werbowsky
  • Publication number: 20050159848
    Abstract: A method and control is provided wherein the sensors in a plurality of zones are properly associated with the dampers associated for each of the zones after installation. A technician goes to each zone and sends a signal from the sensor, and the control then makes a change at the associated damper. The technician can then ensure the two are properly associated within the control.
    Type: Application
    Filed: May 7, 2004
    Publication date: July 21, 2005
    Inventors: Rajendra Shah, Christopher Puranen
  • Publication number: 20050155365
    Abstract: A zoned HVAC system is provided with a series of dampers. A control for the dampers causes the dampers to each move between open and closed positions while monitoring a system condition. The system condition is selected to be one that should change as the damper moves between open and closed positions. If the system condition does not change as the control orders the damper to move between the open and closed positions, the particular damper is identified as a potentially faulty damper.
    Type: Application
    Filed: May 7, 2004
    Publication date: July 21, 2005
    Inventors: Rajendra Shah, Christopher Puranen
  • Publication number: 20050159924
    Abstract: An HVAC system includes a central controller which communicates with a multiple of HVAC components over a digital communication bus. The central controller maintains an ordered fault list that includes the source of a fault, a description of the fault, the last occurrence of the fault, and the number of sequential occurrences, or repetitions across the entire HVAC system.
    Type: Application
    Filed: May 10, 2004
    Publication date: July 21, 2005
    Inventors: Rajendra Shah, Chris Puranen
  • Publication number: 20050154495
    Abstract: Static pressures are measured in an HVAC system and utilized to predict the condition of a filter in the HVAC system. As the filter becomes clogged, the static pressure can be expected to increase. Changes in the static pressure are determined periodically, and utilized to predict the condition of the filter. A display provides a user with an indication of the current condition of the filter, and a recommendation to replace the filter once it reaches a predetermined condition.
    Type: Application
    Filed: December 18, 2003
    Publication date: July 14, 2005
    Inventor: Rajendra Shah