Abstract: An automatic document feeder installed on a copying machine. This document feeder is constructed such that one reversible motor provides the drive power for all of drive parts of the document feeder, that is, a document feeding part, a document conveying part and a document recovering part, thus substantially reducing the manufacturing cost of the feeder. The document conveyor belt, on which a document to be copied is closely laid, moves in the forward and reversed direction, thereby causing the document to be exactly set on a reference copying position of a contact glass of the copying machine and, in this respect, improving the operational efficiency of the automatic document feeder. The present invention also provides a control circuit for automatically controlling such an automatic document feeder.

Abstract: An automatic document feeder (ADF) with a solid bracket suitable for use with an office machine to separate a plurality of documents one by one, and to feed the separated document to the office machine. The solid bracket comprises a pair of side plates, a stationary belt supporter and a shaftless roller supporter extending between the side plates, and a pair of spring supporters connected to the side plates through individual bent connections. The ADF further includes a rotatable shaft supporting the belt and controlling the tensile force of the belt, and a document separating roller coming into close contact with the belt at a position opposed to a shaftless roller. The tension coil springs are connected between the rotatable shaft and the spring supporters to bias the rotatable shaft and to control the tensile force of the belt. The endless document separating belt is rotatably supported by both the stationary belt supporter and the rotatable shaft.

Abstract: A method for manufacturing mask ROMs is disclosed, wherein a semiconductor substrate of a first conductive type, on which a gate insulating layer, a poly-silicon layer, source and drain regions and a spacer are formed is stored after depositing the entire surface of the structure with a protection layer until the next steps such as programming, so that the poly-silicon gate and the source and drain regions of the structure can be prevented from being polluted with organisms or matriums, etc. by forming a protection layer before the storage, thereby improving the efficiency and reliability of mask ROMs, and the ROM data region can be checked during the etching of the protecting layer for distinguishing the defective chips simply and efficiently in a short manufacturing time.

Abstract: A ZrO.sub.2 powder of very fine particle size adapted especially for the making of high density ceramics is produced by chlorinating a zirconium source material, such as zircon sand, to produce crude ZrCl.sub.4 solids; the solids are dissolved to form a ZrOCl.sub.2 solution from which ZrOCl.sub.2 crystals are precipitated; the crystals are dried and milled to a desired particle size; and the crystal particles are subjected to direct oxidation under controlled conditions to produce a very fine ZrO.sub.2 powder especially adapted to the making of high density ceramics.

Abstract: This is a high quality zirconium or hafnium sponge, a fuel element cladding liner having material of the quality of this sponge and a process utilizing this quality sponge to fabricate liner material for lined fuel element cladding. The sponge contains 250-about 350 ppm of oxygen impurity, 50-300 ppm of iron impurity, and a total of 500-1,000 ppm of impurity. This material is much purer than conventional sponge and approaches the quality of crystal bar.

Abstract: A process for distilling zirconium sponge in an iron containing vessel at a temperature sufficiently low to preclude iron contamination of said sponge is disclosed. A distillation temperature near about 934.degree. C. is sufficiently low to minimize iron contamination while being sufficiently high to cause sintering of the sponge to a degree that subsequent comminution does not produce excessive fines.

Abstract: Disclosed is a method for making silane. A silicon tetrahalide having the general formula SiX.sub.4 is reacted with a compound which can be alcohols to C.sub.4, alkanes to C.sub.4, alkenes to C.sub.4 alkenes to C.sub.4 or a mixture thereof, where X is independently selected from the halogens, to produce a product having the general formula SiR.sub.4, where each R is independently selected from alkoxy to C.sub.4, alkyl to C.sub.4, alkylene to C.sub.4 and alkenyl to C.sub.4. The SiR.sub.4 is then reacted with hydrogen to produce the silane.

Abstract: This is a process for producing high quality zirconium or hafnium sponge. It is especially useful for producing the very high purity zirconium which may be used to line the inner surface zirconium of Zircaloy tubing for nuclear fuel rods. The process uses a combination reduction-distillation vessel which is directly fed with zirconium or hafnium tetrachloride from a molten salt sublimer. A precharge of magnesium chloride is used to prevent reduction of metal outside the inner liner, and thereby facilitate removal of the inner liner after reduction and distillation. The agitator for the molten salt sublimer preferably utilizes a molten metal seal around the agitator shaft.

Abstract: This is a method for reduction of chlorides of zirconium, hafnium or titanium, and provides a practical method of removing the product metal from the reduction vessel. A seal metal layer is used at the bottom of the vessel. The upper portion of the seal metal layer is liquid and the lower portion is solid. Product metal settles into the liquid portion. Product metal in a matrix of solid seal metal is withdrawn from the bottom of the vessel. Seal metal is predominantly either zinc or tin. Either pure zinc or tin or zinc or tin alloyed with product metal can be recycled to the bottom of the reduction vessel.

Abstract: This is a method for reducing the chlorides of zirconium, hafnium, or titanium. It utilizes a solidified magnesium (or sodium) chloride matrix in which chunks of the product metal are contained as a seal on the bottom of the reduction vessel. A withdrawal mechanism is used in conjunction with a cooling means (e.g. water jacket) to slowly withdraw the product metal chunks in the salt matrix. This invention makes possible the operation of the reduction process as a continuous process.

Abstract: A combination reduction, distillation, reducing metal recovery furnace and process of using the same comprising a pair of vertically displaced vessels in fluid communication wherein the upper vessel contains a perforated inner liner and means to at least periodically charge the top of the vessel with the metal salt to be reduced and a reducing metal, and wherein the lower vessel has a means to periodically withdraw the molten reducing metal salt produced by the redox reaction occurring within the furnace. By initially charging the furnace with sufficient reducing metal salt to establish a liquid level to provide a liquid seal above the bottom of the inner liner and by maintaining this level during the redox reaction, the inner liner can be filled with solid phase reduced metal produced by the reaction (and no reduced metal is produced outside of the liner).

Abstract: This is a control method for large scale batch reduction of zirconium tetrachloride to zirconium metal. Solid zirconium tetrachloride is fed at least periodically into a sublimer and the sublimer heated to vaporize the zirconium tetrachloride. The vaporized zirconium tetrachloride is fed from the sublimer to a reduction vessel and a measurement is made indicative of this feed (e.g., the flow rate or the pressure in the reduction vessel). A condenser is used to conjunction with said sublimer and the temperature of the condenser is controlled to control the feed of the vaporized zirconium tetrachloride. Preferably, a flow restriction is used between the sublimer and the condenser to provide improved control.