Abstract: A compact laser printer has an up-side down arrangement of components within a machine housing. That is, an optical writing unit is disposed below a rotatably supported photosensitive drum and an image transferring unit is disposed above the photosensitive drum with a developing unit disposed substantially in a side-by-side relationship with the photosensitive drum. A paper feed cassette is located below the optical writing unit when detachably set in position and a paper transportation path extends from the supply end of the paper feed cassette around the developing unit generally in the shape of "U." The machine housing has a pivotally movable portion which may be pivotted open and closed. The photosensitive drum and/or one of a pair of registration rollers may be mounted on the pivotally movable portion.

Abstract: An inverting apparatus comprises: a capacitor input type rectifying circuit consisting of a full-wave rectifier and a smoothing capacitor; a single-phase bridge inverter having four semiconductor switches; and a driving control unit for opening and closing the semiconductor switches, wherein the smoothing capacitor is provided with a switch to open and close the smoothing capacitor.

Abstract: An automatic line spacing device which can be advantageously incorporated in typewriters, especially of the type which has no constantly rotating power shaft. A feed pawl is mounted on a rockable member and cooperates with a ratchet to angularly rotate a typewriter type platen. The rockable member is constantly coupled to a bidirectional electric motor which is first energized sufficiently to angularly rotate the rockable member from its home position to a rotated limit position defined by a fixed positive stop element for effecting a line spacing operation and then secondly energized sufficiently to rotate the rockable member back to its home position as defined by another stop element. A cam adjusts the angle during which the feed pawl engages the ratchet so as to effect different line spacing increments.

Abstract: A ribbon lift device for selectively positioning a print ribbon and a correction ribbon to a print position for printing or correction of a character includes a first cam having a cam groove formed therein for lifting the print ribbon to the print position and a second cam having a cam profile for lifting the correction ribbon to the print position. Means are provided for coupling the first and second cams such that forward rotation of the first cam will not rotate the second cam but reverse rotation of the first cam will rotate the second cam in the same direction, and a bidirectional electric motor is coupled to the first cam whereby rotation of the motor will lift the print ribbon or the correction ribbon, depending upon the direction of rotation.

Abstract: A method for the removal of mercury contained in a sulfur dioxide-containing gas which comprises contacting the sulfur dioxide-containing gas with an aqueous thiourea solution which optionally contains an acid at an acid concentration higher than one normal to selectively absorb mercury in a vapor state.