Abstract: During a method for manufacturing an ink-jet print head, piezoelectric element bars are fixed to a base plate. Then, two corners of the piezoelectric element bars are cut. The bare are then diced to be separated into individual piezoelectric elements.

Abstract: To increase the size of dot printed on a print medium with an on-demand multi-nozzle ink jet head, at least two unit pulses are applied in succession to a piezoelectric element which varies the volume of an ink chamber. The unit pulse has a pulse width substantially equal to a period of Helmholtz natural oscillation determined based on dimensions, materials, and physical properties of an ink channel and the piezoelectric element and other components relating to oscillation. An off duration between adjacent unit pulses applied in succession to the piezoelectric element is preferably set one fifth to one fourth of the unit pulse width.

Abstract: A print head for ink jet printer having a reduced length in a main scanning direction and an elongated length in an auxiliary scanning direction perpendicular to the main scanning direction. A plurality of linear print head modules are arrayed in the auxiliary scanning direction, and each linear print head module extends in a slanting direction with respect to the main scanning direction by a predetermined angle. Further, each linear print head module has a width in a direction perpendicular to its extending direction. The slanting angle and the width determine scanning pitch extending in the auxiliary scanning direction and can reduces the length of the print head in the main scanning direction.

Abstract: To eliminate influence of cross-talk in an on-demand multi-nozzle ink jet head, drive pulses to be applied to piezoelectric elements for driving nozzles aligned in a row are individually adjusted so that the nozzles eject ink droplets at the same speed when the nozzles are driven simultaneously. To the piezoelectric elements which are deactuated during printing, a dummy drive pulse having a voltage level in a range from 50 to 75% of a minimum voltage for ejecting an ink droplet is applied, whereby the ejection speed achieved when individual nozzles are driven approaches the ejection speed achieved when all nozzles are driven simultaneously. As such, the print quality is improved.

Abstract: A piezoelectric element is driven by a predetermined pulse width in the range of 60 to 100% of the Helmholtz resonance vibration period of an ink vibration system comprising an orifice, a pressurizing chamber, a restrictor, the piezoelectric element, and an elastic material.

Abstract: An on-demand multi-nozzle ink jet head includes a diaphragm and a plurality of piezoelectric stacks. The diaphragm forms at least one wall of a pressurizing chamber used to increase the pressure of the ink. When print signals are applied to the piezoelectric stacks. The stacks generate pressure fluctuations in the walls of the pressurizing chamber. An elastic material with adhesive properties is used to bond the diaphragm to the piezoelectric stacks, which elastic material has a Shore hardness of less than 80 on the A scale and less than 30 on the D scale.

Abstract: A hot-melt type ink jet printer includes a nozzle array, an ink tank containing a hot-melt ink therein, and an ink supply tube connecting the ink tank and the nozzle array, wherein a hot-melt ink is used which is a solid at room temperature but liquifies when heated. The ink supply tube is made of an elastic material that contracts and deforms corresponding to contractions and deformations of the ink contained in the ink supply tube. A cap is attached to the tip end of the ink supply tube so that the inlet of the ink supply tube that is in the ink tank faces to the side or upward.

Abstract: A suction purging unit for removing dusts solidified ink etc. from nozzles of a print head of an ink jet printer, the nozzles being arrayed in a moving direction of the print head. A contact portion is provided at one side of a body portion in which a fluid passage is formed. The contact portion is contactable with at least one of the nozzles for suction purging, and is separated from the nozzle between-suction purging mode. The body portion is pivotally movable toward and away from the print head, and is vertically movable. The body portion is movable along a top surface of the print head when the latter is moved in the moving direction.

Abstract: A head arm for use in a magnetic disk drive, comprising a guide arm disposed between a magnetic head and an actuator so as to transmit actuating force of the actuator to the magnetic head thereby guiding the magnetic head along a plane of a magnetic disk, a printed circuit fixed to the guide arm, and deflection compensating member for making the coefficients of thermal expansion of said guide arm and said printed circuit substantially equal to each other in at least the direction of seek of the head arm. No thermal deformation in an out-of-plane direction occurs on such a head arm regardless of any variation in the temperature of the environment in which the magnetic disk drive is installed. A head arm may also comprise a guide arm and a printed circuit formed of a moisture absorptive material and covered at all or part of its surfaces with a covering layer formed of a moisture resistive material not permeable to moisture.

Abstract: A combustion gas powered tool includes a member defining a part of cylindrical combustion chamber having an axis. A piston is movable in a direction along the axis of the combustion chamber. The piston defines the combustion chamber in conjunction with the member. A mixture of air and fuel is generated in the combustion chamber. The air-fuel mixture in the combustion chamber is burned to drive the piston. An orifice grille extends in the combustion chamber, and is parallel to the axis of the combustion chamber.

Abstract: A head arm for use in a magnetic disk drive, comprising a guide arm disposed between a magnetic head and an actuator so as to transmit actuating force of the actuator to the magnetic head thereby guiding the magnetic head along a plane of a magnetic disk, a printed circuit fixed to the guide arm, and deflection compensating member for making the coefficients of thermal expansion of said guide arm and said printed circuit substantially equal to each other in at least the direction of seek of the head arm. No thermal deformation in an out-of-plane direction occurs on such a head arm regardless of any variation in the temperature of the environment in which the magnetic disk drive is installed. The head arm may also comprise a guide arm and a printed circuit formed of a moisture absorptive material and covered at all or part of its surfaces with a covering layer formed of a moisture resistive material not permeable to moisture.

Abstract: A combustion gas powered fastener driving tool includes inlet and outlet openings through which the combustion gases are discharged from a combustion chamber. These openings are located above the uppermost driving position (top dead center) of a slidable piston, so that an air and fuel mixture is fully trapped in the combustion chamber until after it is combusted. Since an outflow of the unburnt air and fuel mixture is completely prevented, the rate of fuel consumption of the fastener driving tool is high and there is no danger of accidental explosion of unburned fuel even when the fastener driving tool is used in a badly ventilated working place or site. An electric fan for forcing fresh air into the combustion chamber is disposed outside the cylinder and isolated from high temperatures. The fan is durable in structure and reliable in operation.

Abstract: In an inverter device comprising a main circuit section which switches a power at high speed, having a switching element and a smoothing condenser for smoothing the power supplied to the switching element, and a logic section for controlling the main circuit section, a shielding member is disposed between the main circuit section and the logical section. The shielding member includes a combination of a heat shielding member and an electromagnetic shielding member so as to protect the logic section from heat, electromagnetic noise, and vibration generated in the main circuit section for improving reliability of the inverter device.

Abstract: An LSI temperature controlling system has closed LSI cooling water circuit, and a refrigeration circuit including a motor-driven refrigerant compressor, a first heat exchanger for exchanging the heat of the LSI cooling water and the refrigerant and a second heat exchanger for exchanging the heats of the refrigerant and another fluid. The motor speed is controlled by an inverter the operation of which is controlled based on the temperature of the LSI cooling water measured by a temperature detector. A heater is used to suppress dew formation on LSI substrates.

Abstract: An apparatus for containing semiconductor wafers and performing heat treatment thereon. Heaters disposed in a high temperature furnace form at least one heating space therein. An insertion and retrieval aperture is disposed at the lower portion of each heating space for allowing passage of wafers therethrough. Each of the heating spaces is adapted to receive one or two wafers and to provide simultaneous and uniform heat treatment on the wafers.

Abstract: This invention relates to a falling film evaporator which is arranged to cause a liquid film to flow downward to thereby effect heat exchange using evaporation. In a space of an evaporating compartment, a gas-liquid separator is disposed to communicate with a compressor which constitutes a part of a refrigeration cycle.

Abstract: A heat exchanger comprising fins and at least one heat transfer tube. An even number, not smaller than four, of louvers are severed and raised in an alternate and staggered manner with respect to a fin base line between the remaining adjacent fin base. Furthermore, the louvers raised on the same side with respect to the fin base line have heights defined by a line slanted at a constant angle in a stepped manner.