Abstract: An etching method of etching Si or SiN existing on a substrate, includes: forming an oxide film on a surface of Si or SiN by performing a radical oxidation process on the substrate having Si or SiN; performing a gas-based chemical process on the oxide film; and removing reaction products produced by the gas-based chemical process, wherein the forming the oxide film, the performing the gas-based chemical process, and the removing the reaction products are repeated a plurality of times.

Abstract: A torque variation absorbing device includes a first flywheel and a second flywheel which are rotatable relative to each other via a ball bearing. A hysteresis mechanism is disposed between the first flywheel and the second flywheel so that the first flywheel and the second flywheel are biased in directions away from each other. The ball bearing includes an outer race, an inner race, and a plurality of balls disposed in a space defined between the outer race and the inner race. A ball inlet groove is formed in each of the outer race and the inner race so that the each ball inlet groove opens toward the hysteresis mechanism. The hysteresis mechanism pushes the outer race and the outer race pushes the balls so that the pushed balls push the inner race in a direction away from the hysteresis mechanism.

Abstract: An apparatus for absorbing torque vibration comprises inertial bodies comprising first and second flywheels, and a damper mechanism, torque limiting mechanism and hysteresis mechanism interposed between the first and second flywheels.The rotation is transmitted between both flywheels via damper mechanism, torque limiting mechanism and hysteresis mechanism. Resilient members are secured to spring seats, which are engaged with both ends of a spring of the damper mechanism, at an inner-half portion of the spring seat closer to the axis of said flywheels than an axial line of the spring. Excess compression of the resilient members is prevented.

Abstract: A rotating member such as a sprocket to be coupled with a shaft is formed with a fitting bore which extends on the center axis and opens at at least one of its axial end portions. The rotating member is arranged in and rotatably held by a case such that its fitting bore opens toward the outside of the case. The shaft is inserted into and coupled with the fitting bore held in the case such that it can rotate integrally with the rotating member. This rotating member is formed with an air communication portion for providing communication between the inside and outside of the fitting bore and equipped with a valve for opening or closing the air communication portion. The valve may be opened in response to the rise or drop in the internal pressure of a fitting bore, by the pressure of the shaft or by a centrifugal force. With the valve being closed, lubrication oil in the case is prevented from leaking.

Abstract: In a gear synchronizer mechanism including a gear member rotatable on a shaft and having a cylindrical hub portion, a hub member mounted on the shaft for rotation therewith, a clutch sleeve formed at its one side with an internal conical surface and at its inner periphery with internal spline teeth in continual engagement with external spline teeth of the hub member and being axially shiftable on the hub member to be engaged at its internal spline teeth with external spline teeth of the hub portion, and a synchronizer ring formed with an external conical surface for frictional engagement with the internal conical surface of the sleeve and being axially movable on the hub portion to establish synchronization between the shaft and the gear when engaged with the sleeve, the hub portion of the gear is formed at its inner periphery with an annular groove and has a plurality of circumferentially spaced radial grooves defined therein, each of which receives therein a corresponding radially movable key element, and t

Abstract: A liquid crystal display having plural liquid crystal cells which are constituted as a matrix, each cell respectively having one transistor and being supplied with image signals by such transistors. The driving circuit for a liquid crystal display of the present invention periodically changes the polarity of the voltage of the image signals and the voltage between both terminals of the liquid crystal cell so as to switch the transistor, and the driving circuit generates gate signals which are impressed on the gate electrode of each transistor, the gate signals having a lowest voltage which is lower than a voltage obtained by subtracting the amplitude voltage of the common electrode of the liquid crystal cells from the lowest voltage in the driving voltage obtained from the image signals.

Abstract: A driver circuit for a liquid crystal display for driving a liquid crystal panel in an A.C. manner. In this circuit, a display signal voltage to be applied to one electrode of the liquid crystal cell and a common voltage to be applied to a common electrode thereof are inverted in their polarity with a certain period, respectively, and at least one of the signal voltage and common voltage that are being polarity-inverted with the certain period is varied in its D.C. level by the same amount in the same direction in each period so that they can be adjusted so as to be in a predetermined relation for A.C. driving.