Abstract: In a needle bar transfer device for a multi-needle sewing machine, a depressing member is secured to a needle bar descending lever for aligning entire needle bars in an equal height at the time of transferring the needle bars, while a needle bar holding member is extended from the needle bar descending lever. Holding portions which are engageable with recessed portions provided at the upper ends of inoperative needle bars and an escape portion which receives an operative needle bar in an interference preventing manner are provided in the needle bar holding member.

Abstract: A multiple needle sewing machine is provided with two needles which are mounted for vertical reciprocating movement in a block which may be laterally shifted between a first position and an second position wherein the first and second needles will be selectively engaged with a vertically reciprocating drive member. A first solenoid is energized to lower a needle bar holding member which is engaged with the inoperative needle to lower the inoperative needle to a position corresponding to the operative needle prior to the lateral shifting of the needles by means of a second solenoid. Subsequent to the lateral shifting of the needle bars to engage the vertical reciprocating member with the previously inoperative needle bar, the previously operative bar will be raised upwardly by the needle bar holding device upon deenergization of the solenoid by a suitable spring.

Abstract: Stabilized zirconia refractories comprising fine block crystals of zirconia, having a high bulk density due to their dense texture and a higher bending strength than the conventional calcined zirconia refractories are disclosed. The stabilized electrocast zirconia refractories are obtained by pouring an electrofused melt of a blend of a zirconia-base material and a stabilizing agent into a mold and solidifying the poured melt from its lower portion by cooling the bottom part of the mold forcibly. Also the method for producing the stabilized electrocast zirconia refractories is disclosed.

Abstract: Disclosed herein is the reinforced electrocast zirconia refractories showing an extremely high bending strength obtained by the heat-treatment of stabilized electrocast zirconia refractories under the specified conditions.

Abstract: A method of repairing an injured portion of a refractory furnace-lining characterized by cutting off the injured portion of said lining through the furnace shell using a specific supersonic flame jet cutter; inserting a rigid refractory lining block having a shape which is similar to that of the through-cut hole of the furnace body; and welding the surrounding periphery of the inserted block to the contact surface of said through-cut hole using the above-mentioned supersonic flame jet cutter as a welder, followed by repairing the outside cut-off shell portion of the furnace body.