Abstract: An apparatus includes a sensor body and a sensor configured to measure pressure. The apparatus also includes at least one pressure input in or on the sensor body, where the at least one pressure input is configured to provide at least one input pressure to the sensor. The apparatus further includes multiple fluid passages configured to convey the at least one input pressure from the at least one pressure input to the sensor using a fill fluid. The multiple fluid passages are configured to both (i) transport the fill fluid and (ii) absorb thermal energy in a flame created by the sensor before the flame exits the sensor body. The fluid passages can include long and narrow straight passages, long and narrow curved or helical passages, and turns or bends. The fluid passages can have small cross-sections relative to their lengths.

Abstract: A scanning measurement system includes independently driven, self-aligning, dual-sided heads. The system is configured to perform a method that includes receiving information associated with a discrepancy in a desired cross direction alignment of a first sensor head and a second sensor head that are disposed on opposite sides of a web of material and that are configured to move in a cross direction relative to the web. The method also includes adjusting a velocity of at least one of the sensor heads based on the received information to improve the cross direction alignment of the first sensor head and the second sensor head.

Abstract: An apparatus includes a sensor body and a sensor configured to measure pressure. The apparatus also includes at least one pressure input in or on the sensor body, where the at least one pressure input is configured to provide at least one input pressure to the sensor. The apparatus further includes multiple fluid passages configured to convey the at least one input pressure from the at least one pressure input to the sensor using a fill fluid. The multiple fluid passages are configured to both (i) transport the fill fluid and (ii) absorb thermal energy in a flame created by the sensor before the flame exits the sensor body. The fluid passages can include long and narrow straight passages, long and narrow curved or helical passages, and turns or bends. The fluid passages can have small cross-sections relative to their lengths.

Abstract: An apparatus includes a sensor body and a sensor configured to measure differential pressure. The apparatus also includes first and second coplanar pressure inputs in or on the sensor body, where the pressure inputs are configured to provide multiple input pressures to the sensor. Each pressure input includes a barrier diaphragm configured to move in response to pressure and an overload diaphragm configured to limit movement of the barrier diaphragm. First and second fill fluid may be configured to convey the pressures from the barrier diaphragms of the pressure inputs to the sensor as first and second input pressures. Passages may be configured to transport the fill fluid between (i) gaps between the barrier diaphragms and the overload diaphragms of the pressure inputs and (ii) the sensor and gaps between the overload diaphragms and the sensor body.

Abstract: A pressure sensor includes a housing with a cavity. The cavity includes a fill fluid and a compensation material. The fill fluid conveys a pressure from a process fluid through a diaphragm to a sensor. The compensation material reduces a difference of thermal expansions between the cavity and the fill fluid.

Abstract: An apparatus includes a chassis configured to move back and forth along multiple rails. The apparatus also includes electrical contacts configured to form electrical connections to the rails. The apparatus further includes a power converter/conditioner configured to receive power from the rails via the electrical contacts and to convert the power into a different form and/or condition the power. In addition, the apparatus includes one or more sensors configured to measure at least one characteristic of a material, where the one or more sensors are configured to operate using the power from the power converter/conditioner. The electrical contacts could touch the rails and receive the power directly from the rails. The electrical contacts could also touch rail contacts and receive the power indirectly from the rails via the rail contacts.

Abstract: A gap and displacement magnetic sensor system for scanner heads in paper machines or other systems includes a multiple-sensor assembly. The multiple-sensor assembly includes multiple magnetic field orientation sensors configured to capture measurements of a magnetic field in order to identify (i) a displacement of first and second scanning sensor heads in a first direction, and (ii) a gap separation of the first and second scanning sensor heads in a second direction, and (iii) a displacement of the first and second scanning sensor heads in a third direction. At least one of the magnetic field orientation sensors is disposed offset from a centerline of the magnetic field such that an output from the at least one magnetic field orientation sensor indicates a combination of the gap separation and the displacement in either the first direction or the third direction.

Abstract: A method includes receiving distance measurements from at least one scanning head that moves back and forth across at least one surface of a web of material on a frame. The distance measurements identify measured distances to the web. The method also includes controlling one or more actuators in order to move at least a portion of the frame to alter a position of the at least one scanning head relative to the web. The one or more actuators could be controlled so that the at least one scanning head maintains a substantially fixed offset from the web as the at least one scanning head moves back and forth. The one or more actuators could also be controlled so that the web maintains a substantially fixed position between multiple scanning heads as the scanning heads move back and forth.

Abstract: A method includes receiving distance measurements from at least one scanning head that moves back and forth across at least one surface of a web of material on a frame. The distance measurements identify measured distances to the web. The method also includes controlling one or more actuators in order to move at least a portion of the frame to alter a position of the at least one scanning head relative to the web. The one or more actuators could be controlled so that the at least one scanning head maintains a substantially fixed offset from the web as the at least one scanning head moves back and forth. The one or more actuators could also be controlled so that the web maintains a substantially fixed position between multiple scanning heads as the scanning heads move back and forth.

Abstract: A system includes a frame having multiple separate supports and multiple flexible rails. Each support is configured to be secured in a position apart from another support, and each flexible rail is configured to be coupled to the supports and placed under tension. The system also includes a sensor head configured to be mounted on the rails and to move back and forth along the rails. The sensor head is substantially self-contained and configured to receive operating power over the rails. The frame may further include a tensioned member configured to be coupled to the supports, and the sensor head can be configured to move back and forth using the tensioned member. The sensor head can be self-contained in that the sensor head does not push and pull any wiring assembly during movement along the rails.

Abstract: A gap and displacement magnetic sensor system for scanner heads in paper machines or other systems includes a multiple-sensor assembly. The multiple-sensor assembly includes multiple magnetic field orientation sensors configured to capture measurements of a magnetic field in order to identify (i) a displacement of first and second scanning sensor heads in a first direction, and (ii) a gap separation of the first and second scanning sensor heads in a second direction, and (iii) a displacement of the first and second scanning sensor heads in a third direction. At least one of the magnetic field orientation sensors is disposed offset from a centerline of the magnetic field such that an output from the at least one magnetic field orientation sensor indicates a combination of the gap separation and the displacement in either the first direction or the third direction.

Abstract: A scanning measurement system includes independently driven, self-aligning, dual-sided heads. The system is configured to perform a method that includes receiving information associated with a discrepancy in a desired cross direction alignment of a first sensor head and a second sensor head that are disposed on opposite sides of a web of material and that are configured to move in a cross direction relative to the web. The method also includes adjusting a velocity of at least one of the sensor heads based on the received information to improve the cross direction alignment of the first sensor head and the second sensor head.

Abstract: A method includes moving a first sensor assembly to a plurality of cross direction positions relative to a second sensor assembly, where the first and second sensor assemblies are configured to move in the cross direction relative to a web of material. The method also includes, for each of the plurality of cross direction positions, determining a sensor value associated with a sensor source disposed at the second sensor assembly as measured by a sensor receiver disposed at the first sensor assembly. The method further includes determining a starting alignment position of the first sensor assembly to be a first cross direction position where a difference between the sensor value at the first cross direction position and a corresponding sensor value at one or more adjacent cross direction positions is a minimum.

Abstract: An apparatus includes a scanning head configured to move one or more sensors back and forth across a surface of a moving web of material. The apparatus also includes a vibration dampening device configured to reduce vibrations of the one or more sensors when the scanning head moves the one or more sensors back and forth across the surface of the web. The vibration dampening device includes at least one mass and one or more springs configured to create oscillatory movement of the at least one mass. The at least one mass and the one or more springs can be located within a housing that rides on a rail back and forth to move the scanning head across the surface of the web. The at least one mass and the one or more springs can also be located on a web deflector connected to the scanning head.

Abstract: An apparatus includes a cable track configured to be coupled to a moveable object and to be pushed and pulled by the movable object without buckling. The cable track is configured to transport at least one signal or material to or from the moveable object. The cable track has a fluid compartment defined between walls of the cable track. The walls of the cable track are configured to be separated when fluid is inserted into the fluid compartment and to approach one another in a bent portion of the cable track. The cable track may further include a web coupled to the walls, where the web is configured to limit the separation of the walls.

Abstract: An apparatus includes a chassis configured to move back and forth along multiple rails. The apparatus also includes electrical contacts configured to form electrical connections to the rails. The apparatus further includes a power converter/conditioner configured to receive power from the rails via the electrical contacts and to convert the power into a different form and/or condition the power. In addition, the apparatus includes one or more sensors configured to measure at least one characteristic of a material, where the one or more sensors are configured to operate using the power from the power converter/conditioner. The electrical contacts could touch the rails and receive the power directly from the rails. The electrical contacts could also touch rail contacts and receive the power indirectly from the rails via the rail contacts.

Abstract: An apparatus includes a cable track configured to be coupled to a moveable object and to be pushed and pulled by the movable object without buckling. The cable track is configured to transport at least one signal or material to or from the moveable object. The cable track has a fluid compartment defined between walls of the cable track. The walls of the cable track are configured to be separated when fluid is inserted into the fluid compartment and to approach one another in a bent portion of the cable track. The cable track may further include a web coupled to the walls, where the web is configured to limit the separation of the walls.

Abstract: An apparatus includes a scanning head configured to move one or more sensors back and forth across a surface of a moving web of material. The apparatus also includes a vibration dampening device configured to reduce vibrations of the one or more sensors when the scanning head moves the one or more sensors back and forth across the surface of the web. The vibration dampening device includes at least one mass and one or more springs configured to create oscillatory movement of the at least one mass. The at least one mass and the one or more springs can be located within a housing that rides on a rail back and forth to move the scanning head across the surface of the web. The at least one mass and the one or more springs can also be located on a web deflector connected to the scanning head.

Abstract: Fiber optic sensors employ a high brightness light source such as a fiber optic supercontinuum source, multiplexed superluminescent light emitting diodes, or a broadband tunable laser diode. Light is delivered to the measurement location via fiber optics and sensor optics directs infrared radiation onto material the being monitored that is located in a hostile environment. A disperse element is positioned in the detection beam path in order to separate the wavelengths and to perform spectral analysis. A spectral analysis of the radiation that emerges from the sheet yields information on a plurality of parameters for the material. For papermaking applications, the moisture level, temperature and cellulose content in the paper can be obtained.

Abstract: A rail system made of one or more flexible guide rods, each consisting of a tension rod, is used to support lightweight, mobile devices such as carriages, scanning heads or optical sensors. The rail is configured to permit movement of the mobile device, when driven by an external drive mechanism, along a main scanning direction but prohibits rotational movement of the mobile device. In this fashion, the mobile device remains substantially at the same measured distance from the flat surface of an object, e.g., moving sheet or web, being analyzed.