Abstract: The present invention provides pitch for manufacturing carbon materials, the pitch having a high fixed carbon content and low viscosity and being obtained by using a petroleum-based heavy oil as a material. Pitch is produced by a method comprising: a step for preparing a material oil containing a petroleum-based heavy oil and an indene compound represented by general formula (1) (step 1); a step for thermally treating the material oil (step 2); and a step for distilling the thermally treated product and obtaining pitch as a high-boiling-point component (step 3).

Abstract: Provided is impregnated pitch having a high fixed carbon content despite being petroleum-based pitch. The method for producing impregnated pitch for graphite electrode production according to one embodiment includes heat treatment of ethylene bottom oil and distillation of the heat-treated product to remove low-boiling-point compounds.

Abstract: Disclosed is a two-needle sewing machine that improves strength in a convex curve part by bringing a pair of stitches close together when sewing an item. A two-needle sewing machine includes a bed part; a column part; an arm part; a needle shaft that is disposed on the leading part of the arm part; two sewing needles that are attached to the needle shaft; two horizontal hooks that catch the respective needle thread loops of the two sewing needles; and a conveyor member that conveys a material to be sewn in a direction approximately orthogonal to the bed part. On the two-needle sewing machine, the sewing needle, which is positioned in a location distant from the column part, is disposed closer to the conveyance side of the material to be sewn than the sewing needle that is positioned in a location closer to the column part.

Abstract: To provide a seam of attractive appearance in which tightening force is increased and raveling are prevented drastically. A seam (1) is formed by two needles (11, 12) juxtaposed in the direction at substantially right angles to the sewing direction (T), and consists of a chain seam (10) formed by a needle thread (12) passed through one needle (11), and a lock seam (20) formed by a needle thread (22) passed through the other needle (21). The loop (13) of a needle thread forming the chain seam (10) is passed through the loop (23) of a needle thread forming the lock seam (20) before tightening of stitch is performed, and a loop of the needle thread forming the chain seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam.

Abstract: Disclosed is a two-needle sewing machine that improves strength in a convex curve part by bringing a pair of stitches close together when sewing an item. A two-needle sewing machine includes a bed part; a column part; an arm part; a needle shaft that is disposed on the leading part of the arm part; two sewing needles that are attached to the needle shaft; two horizontal hooks that catch the respective needle thread loops of the two sewing needles; and a conveyor member that conveys a material to be sewn in a direction approximately orthogonal to the bed part. On the two-needle sewing machine, the sewing needle, which is positioned in a location distant from the column part, is disposed closer to the conveyance side of the material to be sewn than the sewing needle that is positioned in a location closer to the column part.

Abstract: The present invention provides a sewing machine that can perform zigzag sewing a cylindrical sewn article. A sewing machine 1 includes an approximately cylindrical guide member 11 that guides a sewn article A, a sewing needle 99 that sews the cylindrical sewn article A, a holding member 71 that holds the sewing needle 99 approximately vertically, a vertical hook 21 provided in the guide member 11 so that the direction of rotation is approximately perpendicular to the axial direction C of the guide member 11 and that catches the upper thread loop of the sewing needle 99, a rotary shaft 22 that rotates the vertical hook 21, and an operating means 50 that moves the holding member 71 and the rotary shaft 22 reciprocatingly at approximately the same time.

Abstract: The present invention provides a sewing machine that can perform zigzag sewing a cylindrical sewn article. A sewing machine 1 includes an approximately cylindrical guide member 11 that guides a sewn article A, a sewing needle 99 that sews the cylindrical sewn article A, a holding member 71 that holds the sewing needle 99 approximately vertically, a vertical hook 21 provided in the guide member 11 so that the direction of rotation is approximately perpendicular to the axial direction C of the guide member 11 and that catches the upper thread loop of the sewing needle 99, a rotary shaft 22 that rotates the vertical hook 21, and an operating means 50 that moves the holding member 71 and the rotary shaft 22 reciprocatingly at approximately the same time.

Abstract: To provide a seam of attractive appearance in which tightening force is increased and raveling are prevented drastically. A seam (1) is formed by two needles (11, 12) juxtaposed in the direction at substantially right angles to the sewing direction (T), and consists of a chain seam (10) formed by a needle thread (12) passed through one needle (11), and a lock seam (20) formed by a needle thread (22) passed through the other needle (21). The loop (13) of a needle thread forming the chain seam (10) is passed through the loop (23) of a needle thread forming the lock seam (20) before tightening of stitch is performed, and a loop of the needle thread forming the chain seam located on a downstream side in the sewing direction is passed through the loop of the needle thread forming the upstream chain seam.

Abstract: A drive device for a sewing machine which varies the speed of the auxiliary motor. In a sewing machine drive device, the rotation of a clutch motor is transmitted through a pulley and an endless belt to the spindle of the sewing machine. The rotation of an auxiliary motor is transmitted through a driving sprocket, a timing belt and a driven sprocket and through the pulley to the spindle of the sewing machine. The drive device includes rotation varying means which varies the rotation of the auxiliary motor in response to the variation in diameter of the driving pulley of the clutch motor.