摘要:
A bubble valve that comprises a liquid delivery channel and a localized heating arrangement. The liquid delivery channel includes an upstream portion and a constriction downstream of the upstream portion. The constriction has a smaller cross-sectional area than the upstream portion. The localized heating arrangement is located in the liquid delivery channel and generates heat to nucleate and enlarge a bubble in the liquid. The constriction is shaped to form a seal with the bubble. The localized heating arrangement additionally generates heat to move the bubble relative to the constriction to control the flow of the liquid. A pressure regulator that comprises a liquid delivery channel connected to a liquid outlet, a sensor located adjacent the liquid outlet, a controller that operates in response to the sensor and a localized heating arrangement. The liquid delivery channel includes an upstream portion, and a constriction located between the upstream portion and the liquid outlet. The constriction has a smaller cross-sectional area than the upstream portion. The localized heating arrangement is located in the liquid delivery channel and generates heat in response to the controller to nucleate and enlarge a bubble in the liquid. The constriction is shaped to form a seal with the bubble. The localized heating arrangement additionally generates heat to move the bubble relative to the constriction to control the flow of the liquid to the liquid outlet.
摘要:
A thermally-activated gas extraction device that comprises a bubble capture chamber, an exhaust manifold, a tapered extraction chamber and an extraction heater associated with the tapered extraction chamber. The tapered extraction chamber extends from the bubble capture chamber towards the exhaust manifold and has a cross-sectional area that increases towards the exhaust manifold. A gas removal method in which the gas extraction device is provided, a bubble of gas is accumulated in the bubble capture chamber, a portion of the liquid in the tapered extraction chamber heated to nucleate a bubble of vapor, and the bubble of vapor is heated to explosively expand the bubble of vapor into contact with the walls of the tapered extraction chamber and into contact with the bubble of gas to form a composite bubble. Contact with the walls of the tapered extraction moves the composite bubble towards the exhaust manifold. Finally, heating of the composite bubble is discontinued to condense the vapor in the composite bubble.
摘要:
A thermally-activated gas extraction device that comprises a bubble capture chamber, an exhaust manifold, a tapered extraction chamber and an extraction heater associated with the tapered extraction chamber. The tapered extraction chamber extends from the bubble capture chamber towards the exhaust manifold and has a cross-sectional area that increases towards the exhaust manifold. A gas removal method in which the gas extraction device is provided, a bubble of gas is accumulated in the bubble capture chamber, a portion of the liquid in the tapered extraction chamber heated to nucleate a bubble of vapor, and the bubble of vapor is heated to explosively expand the bubble of vapor into contact with the walls of the tapered extraction chamber and into contact with the bubble of gas to form a composite bubble. Contact with the walls of the tapered extraction moves the composite bubble towards the exhaust manifold. Finally, heating of the composite bubble is discontinued to condense the vapor in the composite bubble.
摘要:
A gas or liquid detector that includes a capacitative sensor and a capacitance detector. The capacitative sensor includes a first electrode and a second electrode separated from one another, and additionally includes Debye elements extant in the liquid adjacent such portions of the electrodes that are in contact with the liquid. The Debye elements each include a Debye capacitor with an associated shunt conductor. The shunt conductor has an exponentially-increasing conductance versus voltage characteristic. The Debye element adjacent the first electrode and the Debye element adjacent the second electrode are connected in series by conduction through the liquid. The Debye element adjacent at least the first electrode has a substantially greater capacitance than the capacitance between the electrodes absent the Debye elements. The capacitance detector is connected to the capacitative sensor and measures the capacitance of the capacitative sensor by applying an alternating voltage between the electrodes. The alternating voltage has a voltage amplitude less than the voltage amplitude at which the Debye element extant adjacent at least the first electrode ceases to be predominantly capacitative. By measuring the capacitance of the capacitative sensor using an alternating voltage having a voltage amplitude less than the voltage amplitude at which the Debye element ceases to be predominantly capacitative, the capacitances measured are one or more orders of magnitude greater than the capacitances conventionally measured between electrodes in contact with a liquid.
摘要:
An ink jet print head with a substrate defining an ink aperture. A number of ink energizing elements are located on the major surface of the substrate. A barrier layer is connected to the upper surface, and peripherally encloses an ink manifold. The barrier encompasses the ink aperture. An orifice plate is connected to the barrier layer, spaced apart from the substrate's major surface, enclosing the ink manifold. The plate defines a number of orifices, each associated with a respective ink energizing element. The ink manifold is an elongated chamber having opposed ends defined by end wall portions of the barrier layer. The barrier end wall portions each have an intermediate end wall portion protruding into the manifold.
摘要:
A method of manufacturing an ink jet print head with a substrate defining an ink aperture. A number of ink energizing elements are located on the major surface of the substrate. A barrier layer is connected to the upper surface, and peripherally encloses an ink manifold. The barrier encompasses the ink aperture. An orifice plate is connected to the barrier layer, spaced apart from the substrate's major surface, enclosing the ink manifold. The plate defines a number of orifices, each associated with a respective ink energizing element. The ink manifold is an elongated chamber having opposed ends defined by end wall portions of the barrier layer. The barrier end wall portions each have an intermediate end wall portion protruding into the manifold.
摘要:
A high quality inkjet printhead includes a substrate having a multiplicity of heater resistors formed thereon at a density of at least six heater resistors per square millimeter. Each of the heater resistors also has a total resistance of at least 70 &OHgr; and an overlaying passivation thermal barrier characteristic adjusted to enable ejection of an ink drop of less than 6.5 ng with an energy impulse equal to or less than 1.4 &mgr;joules.
摘要:
A switching device for controlling fluid motion. The device includes a capillary filled with a first fluid into which a wall-confined bubble of a second fluid is introduced to achieve a first switching event. Capillary geometry and wetting properties provide a pressure-related asymmetric energy potential distribution for controlling the flow of the bubble, and the device is called an asymmetric bubble chamber, or ABC. The bubble is initially trapped in an energy potential well, and upon increase of its volume moves from the well into a region of low energy potential to achieve a second switching event. The first switching event may be blocking of a fluid channel or reflection of an optical beam in an optical crosspoint switch, while the second switching event may be unblocking of a fluid channel or restoration of transmission of an optical beam. The increase in bubble volume between the first and second switching events can act as the stroke of a fluidic piston to pump a volume the first fluid within the capillary. The device can be employed to thermally degas a liquid. The use of large-magnitude geometry-related energy potentials permits rapid cyclical operation of the device in a manner resistant to mechanical shock.
摘要:
A switching element defines a transmitting state and a reflecting state for a pair of intersecting waveguides that have a gap at their intersection. In the preferred embodiment, the switching element exhibits total internal reflection at the gap sidewall from one waveguide to the other when not in the transmitting state. In the transmitting state, index-matching liquid fills the gap, enabling light to continue in the original waveguide direction. The switching element may use ink jet techniques or bubble techniques to displace index-matching liquid. The index-matching fluid may be projected from a gap between the waveguides by a jet mechanism, or a vapor or dissolved gas bubble may be formed to fill the gap between the waveguides to provide the reflecting state for the switching element. Using either of the techniques, heaters are employed to initiate the switching operation. In some embodiments, more than one heater is utilized. In the preferred embodiment, waveguides are formed on one substrate and heaters are formed on another. Then the substrates are aligned and bonded together to position the heaters in very close proximity to the intersection between the waveguides. Preferably, the switching element is one element in a matrix of such elements for routing signals between arrays of input and output waveguides.
摘要:
A pressure regulator that sets the pressure of a liquid to a predetermined pressure differential below a reference pressure, such as atmospheric pressure. The pressure regulator comprises a liquid delivery channel and a capillary array. The liquid delivery channel includes a liquid input and a liquid output. The liquid flows through the liquid delivery channel from the liquid input to the liquid output. The capillary array is composed of ones of an elongate capillary. The capillary includes a first end in fluid communication with the liquid delivery channel and a second end in pressure communication with a source of the reference pressure. The liquid flows through the first end into the capillary to form a liquid surface in the capillary. The second end is remote from the first end. The capillary has cross-sectional dimensions in relation to the surface tension of the liquid and the angle of contact between the liquid and the capillary such that the pressure drop across the liquid surface in the capillary is equal to the predetermined pressure differential.