Abstract: A control system for a bypass duct includes a pneumatic damper control assembly, a sensor and a pneumatic switch. The damper control assembly includes a damper vane mountable in the bypass duct for movement between relative open and closed positions to regulate airflow through the bypass duct. The position of the damper vane is controllable via pressure applied through a damper control line. The sensor is mountable to the supply duct to transmit a pneumatic supply duct signal via a supply line based on at least one of air pressure or air velocity in the supply duct. Finally, the pneumatic switch opens or closes the connection between the damper control line and the supply line based on the difference between (1) the pneumatic supply duct signal via the supply line, and (2) the combination of the pneumatic pressure from the damper assembly and a switch biasing pressure.

Abstract: A control system for a bypass duct includes a pneumatic damper control assembly, a sensor and a pneumatic switch. The damper control assembly includes a damper vane mountable in the bypass duct for movement between relative open and closed positions to regulate airflow through the bypass duct. The position of the damper vane is controllable via pressure applied through a damper control line. The sensor is mountable to the supply duct to transmit a pneumatic supply duct signal via a supply line based on at least one of air pressure or air velocity in the supply duct. Finally, the pneumatic switch opens or closes the connection between the damper control line and the supply line based on the difference between (1) the pneumatic supply duct signal via the supply line, and (2) the combination of the pneumatic pressure from the damper assembly and a switch biasing pressure.

Abstract: A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Abstract: A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Abstract: A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Abstract: A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Abstract: A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Abstract: A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Abstract: A low friction fluid motor has a diaphragm mounted in a shell to divide the shell into first and second chambers, a port means for connecting the second chamber to a pressure or vacuum source, and an actuator assembly. The actuator assembly is connected to the diaphragm and includes an actuator member extending out of the shell through an aperture. The actuator is free of any seal member which is interposed between the actuator member and the shell and which functions to form a seal between the actuator member and the aperture in the shell. The aperture is oversized relative to the actuator member to allow free passage of the actuator member from the actuator assembly through the first chamber and out of the fluid motor.

Abstract: An apparatus and method for identifying a conduit at a second location remote from a known first location of the conduit, characterized by a vibration device and means for removably coupling the vibration device to a wall of the conduit for transmission of vibration to and/or generation of vibration in the conduit, thereby enabling identification of the conduit at the remote second location.

Abstract: A fluid flow control damper assembly and associated method are characterized by a self-contained unit comprising a support base for external mounting to a side of a duct, a damper vane mounted to the support base for movement between open and closed positions, the damper vane being located inwardly of the inner side of the support base for positioning interiorly of the duct when the support base is mounted to the duct, and an actuator mounted to the support base and operatively connected to the damper vane for moving the damper between the open and closed positions, and wherein the support base functions to close an access opening in a side wall of the duct of sufficient size to permit insertion of the damper vane therethrough.

Abstract: A flow control bladder for controlling flow through a conduit such as an HVAC duct comprises a flexible walled body having a hollow interior and an inflation stem for passing an inflation fluid in and out of the hollow interior thereby transforming the body between an inflated condition for restricted flow through a conduit and a deflated condition for relatively unrestricted flow through a conduit. The body includes first and second panel walls, which normally are generally parallel when the body is in its deflated condition, and opposite side walls connected to the first and second panel walls at respective peripheral side folds. In addition, each side wall includes an inner fold which opens in a direction opposite the peripheral side folds when the body is in its deflated condition. The side walls are preferably folded between the panel walls although they may also be folded over one of the panel walls.

Abstract: An improved zone control apparatus having mode selectors which allow a user to select any one of a variety of operating modes for individual fluidically actuated flow control devices. The invention further provides for a smoke damper which upon automatic or manual activation causes all of the flow control devices to restrict flow of conditioned fluid through respective ducts or pipes so as to help minimize smoke contamination and the formation of a "chimney" effect. The invention further provides for the utilization of vibration type diaphragm pumps to create a source of pressure and vacuum, a pressure test device to quickly check the pressure in the apparatus, and a flow indicator for determining the location of leaks in the apparatus.

Abstract: A zone control apparatus for central heating and/or cooling systems having a central fluid heating and/or cooling plant conduits for directing the heated or cooled fluid to the rooms in a house or other building being serviced by the system. The zone control apparatus comprises one or more flow control devices operatively with respective fluid conduits in the central heating and/or cooling system, and a cycle controller for cycling the flow control device or devices between high and low (or no) flow conditions at times strategically selected to correspond to periods of high and low use of the room or rooms with which the flow control devices are respectively associated. Accordingly, the apparatus operates automatically to eliminate unnecessary heating or cooling of individual rooms or zones during cyclical periods of low or no use whereby substantial energy savings and other benefits may be obtained with minimal compromise in comfort.

Abstract: An improved zone control apparatus having mode selectors which allow a user to select any one of a variety of operating modes for individual fluidically actuated flow control devices. The invention further provides for a smoke damper which upon automatic or manual activation causes all of the flow control devices to restrict flow of conditioned fluid through respective ducts or pipes so as to help minimize smoke contamination and the formation of a "chimney" effect. The invention further provides for the utilization of vibration type diaphragm pumps to create a source of pressure and vacuum, a pressure test device to quickly check the pressure in the apparatus, and a flow indicator for determining the location of leaks in the apparatus.

Abstract: A zone control apparatus for central heating and/or cooling systems having a central fluid heating and/or cooling plant and conduits for directing the heated or cooled fluid to the rooms in a house or other building being serviced by the system. The zone control apparatus comprises one or more flow control devices operatively associated with respective fluid conduits in the central heating and/or cooling system, and a cycle controller for cycling the flow control device or devices between high and low (or no) flow conditions at times strategically selected to correspond to periods of high and low use of the room or rooms with which the flow control devices are respectively associated. Accordingly, the apparatus operates automatically to eliminate unnecessary heating or cooling of individual rooms or zones during cyclical periods of low or no use whereby substantial energy savings and other benefits may be obtained with minimal compromise in comfort.

Abstract: A zone control apparatus for central heating and/or cooling systems having a central fluid heating and/or cooling plant and conduits for directing the heated or cooled fluid to the rooms in a house or other building being serviced by the system. The zone control apparatus comprises one or more flow control devices operatively associated with respective fluid conduits in the central heating and/or cooling system, and a cycle controller for cycling the flow control device or devices between high and low (or no) flow conditions at times strategically selected to correspond to periods of high and low use of the room or rooms with which the flow control devices are respectively associated. Accordingly, the apparatus operates automatically to eliminate unnecessary heating or cooling of individual rooms or zones during cyclical periods of low or no use whereby substantial energy savings and other benefits may be obtained with minimal compromise in comfort.