Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
A flexible and efficient bulk micromachining method for fabricating a novel microstructure that is bounded by substantially planar surfaces meeting only at substantially right angle corner features. The novel microstructure of the present invention is useful as a spacer in assembly processes where high accuracy is required, such as precise positioning of optical fibers or conductors. In the preferred embodiment, the microstructure of the present invention includes a shelf feature disposed along a height dimension of the microstructure, which is required for some applications. The bulk micromachining method of the present invention includes providing a first substrate having a top planar surface and an opposing planar surface. The opposing surface of the substrate is anisotropically etched to provide a first thinned region. The top surface of the first substrate is anisotropically etched so that a first recessed feature having a vertical side is made integral with the first thinned region. Similarly, a second substrate having a top planar surface and an opposing planar surface is provided. The opposing surface of the second substrate is anisotropically etched to provide a second thinned region. The top surface of the second substrate is anisotropically etched so that a second recessed feature having a vertical side wall is made integral with the second thinned region. The top surface of the first substrate is aligned and coupled with the top surface of the second substrate to produce the desired microstructure. The substrates are cut or sawn to free the microstructure.
Abstract:
An integration of a micromachined actuator and a signal transmission structure includes a thermal actuator on a side of a displaceable signal line opposite to a fixed signal line. The actuator includes first and second legs. The first leg has a cross-sectional area greater than the second leg, providing a differential in electrical resistance. As current is channeled through the legs, the second leg will elongate more and will deflect both of the legs. The deflection is in a direction to press the displaceable signal line into signal communication with the fixed signal line. Optionally, a thermally operated reset actuator can be positioned to provide a mechanical return of the displaceable signal line. In a preferred embodiment, a microwave transmission environment is provided.
Abstract:
A process is disclosed for removing residual sulfur from a hydrotreated naphtha feedstock. The feedstock is contacted with molecular hydrogen under reforming conditions in the presence of a less sulfur sensitive reforming catalyst to convert trace sulfur compounds to H.sub.2 S, and to form a first effluent. The first effluent is contacted with a solid sulfur sorbent to remove the H.sub.2 S and form a second effluent. The second effluent is then contacted with a highly selective reforming catalyst under severe reforming conditions. Also disclosed is a method using a potassium containing sulfur sorbent made from nitrogen-free potassium compounds.
Abstract:
A process for removing residual sulfur from a hydrotreated naphtha feedstock is disclosed. The feedstock is contacted with molecular hydrogen under reforming conditions in the presence of a less sulfur sensitive reforming catalyst, thereby converting trace sulfur compounds to H.sub.2 S, and forming a first effluent. The first effluent is contacted with a solid sulfur sorbent, removing the H.sub.2 S and forming a second effluent. The second effluent is contacted with a highly selective reforming catalyst under severe reforming conditions.
Abstract:
A process is disclosed for removing sulfur from a naphtha feedstream comprising contacting a naphtha feed with a platinum on alumina sulfur conversion catalyst under mild reforming conditions so that thiophenic and other organic sulfur compounds are converted to hydrogen sulfide without any significant cracking of the naphtha feed. Thereafter, the naphtha feed stream is contacted with a sulfur sorbent that has a metal component selected from Group I-A or Group II-A of the Periodic Table supported on a refractory inorganic oxide support, to remove hydrogen sulfide from the naphtha feed.