Abstract: A toner density detection method for an electrophotographic apparatus in which driving of a rotary roll provided at an outlet of a special vessel is continued for a predetermined period of time (e.g., several seconds) after the operation of the electrophotographic apparatus is stopped. All or substantially all of the developing agent is thus exhausted or removed from the special vessel after the electrophotographic apparatus is stopped, so that the true permeability of the developing agent can be detected by a permeability sensor when the operation of the electrophotographic apparatus is restarted. As a result, the toner density of the developing agent can be controlled and kept normal, so that the printing quality can be stabilized.

Abstract: An optical fiber composite insulator which includes an insulator body having a through-hole formed in its axis portion and at least one optical fiber extending through the through-hole and sealed in the through-hole by an inorganic vitreous sealing material at both end portions of the through-hole. The sealing material has substantially the same thermal expansion coefficient as that of the insulator body, has high resistances against breakage in the power frequency voltage test and in the lightning impulse voltage test, against crack formation in the cooling and heating test, heat proof test and heat cycle test, and against the light-transmission loss.

Abstract: In a printing sheet conveying device in which a sheet bearing a toner image is passed through a heating roll and a pressure roll, and which has means for changing the right and left contact pressures of these rolls to correct the meandering movement of the sheet when conveyance of the sheet is started; in which when conveyance of the sheet is started, the contact pressure of the rolls is made higher on one of the right and left sides than on the other side, and in a predetermined period of time the contact pressures on both sides are made equal to each other.

Abstract: A fixing roller used in an electrophotographic device includes a coupling with a drive key that engages an end of a pressing roll that contains a key groove. Disposed between the coupling and the end of the pressing roll is a spacing member. This spacing member decreases the rate at which the key groove and the drive key deteriorate when two fixing rollers are used as pair to fix toner on a printed page. The spacing member is made of plastic, a sintered metal alloy, or other material. Also, the spacing member is lubricated to further prevent friction and the key groove of the pressing roll is lined with an abrasion resistant material to further prevent deterioration of the drive key and the key groove.

Abstract: A laser printer with a thermal fixing unit comprises: a pair of heat and pressure rolls for pressing a sheet with a developed toner image therebetween to fix the toner image on the sheet; a web immersable with an oil; an oil coater for supplying the oil to the web and pressing the web against the heat roll at at least one point to make the web contact with the heat roll so that the oil is applied from the oil coater onto the surface of the heat roll through the web to thereby prevent occurrence of offset of the toner image; and at least one pressing member provided separately from the oil coater for locally urging the web against the heat roll, the pressing member being located on at least one of before and behind the oil coater.

Abstract: An optical fiber composite insulator which including an insulator body having a through-hole formed in its axis portion and at least one optical fiber extending through the through-hole and sealed in the through-hole by an inorganic vitreous sealing material at both end portions of the through-hole. The sealing material has substantially the same thermal expansion coefficient as that of the insulator body, has high resistances against breakage in the power frequency voltage test and in the lightning impulse voltage test, against crack formation in the cooling and heating test, heat proof test and heat cycle test, and against the light-transmission loss.

Abstract: Optical fiber-containing insulators each comprises an insulator body having a through hole provided in its central portion and extending along an axial direction thereof, an optical fiber core wire passing through the through hole, an insulating material filled between an inner peripheral surface of the through hole and the optical fiber core wire, and arrangements for preventing the filled insulating material from axially protruding out of the insulator body even at high temperature or spacers for holding the optical fiber core wire at the central portion of the through hole of the insulator body.

Abstract: In order to adapt a thermal head for a thermal printer to a raised speed, the thickness .delta.(.mu.m) of a heat accumulating layer in the head is set at: ##EQU1## where k: temperature conductivity of the heat accumulating layer,t.sub.p : heating duration of the thermal head, andt.sub.O : printing cycle of the thermal head.

Abstract: A thermal head is provided with a heat accumulating member disposed on a substrate, a plurality of heating resistors juxtaposed on the heat accumulating member in a manner to be spaced from each other, electrodes for supplying electric power to the heating resistors, and a protective member for preventing oxidation and wear of the heating resistors and the electrodes, these constituents being formed as layers. When the electric power is supplied to the electrodes, heat is generated by a heating portion of the heating resistor corresponding to the electrodes, and it is transmitted to a head surface via a thermally conductive member disposed in a printing dot portion of the protective member. The heat from the printing dot portion is used for effecting printing on a medium to-be-recorded through a thermosensitive sheet which lies in contact with the head surface.

Abstract: A printing head is disclosed in which each attraction member is driven by a magnetic attraction and an impact printing operation is carried out by a strain energy caused by a displacement of a spring member provided on the attraction member. The fulcrum of rotation of the attraction member is defined between the attraction member and a magnetic polar face of a yoke constituting a magnetic circuit together with the attraction member. Means for adjusting the resilient force of the spring member is engaged with a free end of the spring member.

Abstract: A complex of an acid addition salt of (2'-benzyloxycarbonyl)phenyl trans-4-guanidinomethylcyclohexanecarboxylate and a cyclodextrin. The complex is useful for the treatment of ulcers.

Abstract: A printing apparatus including a plurality of drive coils for driving printing hammers arranged longitudinally in side-by-side relation at one side of a core of the U-shape. A first cooling fluid passageway is defined inside the core of the U-shape to allow a cooling fluid for cooling the drive coils to flow therethrough, and a second cooling fluid passageway is defined outside the core by a duct to allow the cooling fluid for cooling the drive coils to flow therethrough without escaping to the outside by diffusion. A current of cooling fluid is forcibly fed into these cooling fluid passageways by a fluid machine.

Abstract: A printing hammer driving apparatus for high-speed printers comprises a lever member acting as a hammer operating part, an armature forming a part of a magnetic circuit, and an electromagnet forming, together with the armature, the magnetic circuit. The lever member has a rotational supporting point at the base end thereof and is made of a light-weight non-magnetic material. The armature is projected in one of the rotational directions of the lever member from the intermediate part of the lever member. The electromagnet has at least one core and an exciting coil wound on the core. A core has a magnetic pole face perpendicular to the direction of attraction of the armature and a magnetic pole face parallel to the direction of attraction of the armature.

Abstract: A compound of the formula: ##STR1## wherein R.sub.1 represents a vanilyl, napthyl, pyridyl or .alpha.-tocopheryl group, or a group of the formula, ##STR2## wherein R.sub.2 represents a hydrogen atom, a lower alkoxy, formyl, lower alkanoyl or phenyl group, or a group of the formula --(CH.sub.2).sub.n COOR.sub.3, wherein R.sub.3 represents a hydrogen atom, a lower alkyl, phenyl, benzyl, anisyl or lower alkoxycarbonylmethyl group, and n represents an integer of 0 to 2, or a pharmaceutically acceptable salt thereof is effective for use as an anti-ulcer agent.