Abstract: In order to provide a wheel nut wrench in which strength of a nut socket portion is allowed to be increased even though processes are facilitated under a situation where a tube made of carbon steel such as S45C is used as a material, and a manufacturing process thereof, an embodiment to implement the present invention is a wheel nut wrench made with a tube-shaped steel tube and provided with a nut socket portion at least one end, a nut socket shell portion whose inner and outer peripheries are both formed in a hexagonal shape is provided at an end portion of the steel tube, a sleeve made of a steel plate and having a cross section of a hexagonal shape is pressed into the nut socket shell portion, and a portion of the nut socket shell portion is deformed toward the sleeve to thereby achieve unification of the nut socket portion and the sleeve.

Abstract: In order to provide a manufacturing process for a wheel nut wrench in which strength of a nut socket portion is increased even though the process is facilitated under a situation where a tube made of carbon steel such as S45C is used as a material, the process includes the steps of: using a tube-shaped steel tube, forming a nut socket shell portion having a cross section of a hexagonal shape at an end portion thereof by cold pressing, pressing a sleeve made by a belt-shaped steel plate being bent and having a cross section of a hexagonal shape into the nut socket shell portion, and unifying a nut socket portion with the sleeve by plastic deforming.

Abstract: In order to provide a wheel nut wrench in which strength of a nut socket portion is allowed to be increased even though processes are facilitated under a situation where a tube made of carbon steel such as S45C is used as a material, and a manufacturing process thereof, an embodiment to implement the present invention is a wheel nut wrench made with a tube-shaped steel tube and provided with a nut socket portion at least one end, a nut socket shell portion whose inner and outer peripheries are both formed in a hexagonal shape is provided at an end portion of the steel tube, a sleeve made of a steel plate and having a cross section of a hexagonal shape is pressed into the nut socket shell portion, and a portion of the nut socket shell portion is deformed toward the sleeve to thereby achieve unification of the nut socket portion and the sleeve.

Abstract: Since lubricating oil is injected to a tooth of a small-diameter helical gear immediately before meshing begins, the injected lubricating oil can be captured between the small-diameter helical gear and a large-diameter helical gear and successively flow along meshing tooth surfaces. Therefore, lubrication of the tooth surface and cooling of the tooth surface can be simultaneously performed with an appropriate quantity of lubricating oil to enable a reduction in tooth surface wear and a longer gear life. Moreover, a lubricating oil film formed on the tooth surface makes it possible to prevent direct contact between the tooth surfaces of both the small-diameter helical gear and the large-diameter helical gear. Since a covered tooth surface effect is also obtained, the occurrence of pitching and scoring can be suppressed. By injecting lubricating oil directly to the small-diameter helical gear, which has a small heat capacity, a cooling effect thus obtained can suppress a temperature increase of the small gear.

Abstract: A hollow housing of a screw-type jack is integrally formed by a press. A ram is mounted in the center portion inside this housing in an axial direction to be extendable/contractible in a vertical direction. A drive mechanism mounted in the housing, for extending/contracting this ram in the vertical direction, and in which the housing includes a cylindrical shaft portion protrudingly disposed on a lower part of a side surface of the housing. A drive gear is pivotally and rotatably supported in the cylindrical shaft portion. The housing is made up of a plurality of housing pieces which are vertically divided portions of the housing. The housing pieces are mechanically joined to each other to form the housing. The housing pieces are divided in a vertical direction cutting though the axis of the cylindrical shaft portion. Joining of the housing pieces can use rivets or joining pieces can be swaged over protruding flanges.

Abstract: A hollow housing of a screw-type jack is integrally formed by a press. A ram is mounted in the center portion inside this housing in an axial direction to be extendable/contractible in a vertical direction. A drive mechanism mounted in the housing, for extending/contracting this ram in the vertical direction, and in which the housing includes a cylindrical shaft portion protrudingly disposed on a lower part of a side surface of the housing. A drive gear is pivotally and rotatably supported in the cylindrical shaft portion. The housing is made up of a plurality of housing pieces which are vertically divided portions of the housing. The housing pieces are mechanically joined to each other to form the housing. The housing pieces are divided in a vertical direction cutting though the axis of the cylindrical shaft portion. Joining of the housing pieces can use rivets or joining pieces can be swaged over protruding flanges.

Abstract: A flexible tube for an endoscope includes a spiral coil 11 as the innermost layer and a jacket 13 that is formed by applying a melt of a jacket material 1 and then curing it, in which the jacket material 1 has been allowed to penetrate through the gaps between adjacent turns of the innermost spiral coil 11 to reach the portion of its inner surface.

Abstract: A catalyst for the preparation of maleic anhydride by vapor phase catalytic oxidation of benzene with a molecular oxygen containing gas comprising a porous inert support of an alkali metal content, calculated as oxide, of at most 0.3% by weight and supported thereon a catalytic substance of a constituent composition comprising (a) 1 mole of vanadium pentoxide, (b) 0.3 to 1.2 moles of molybdenum trioxide, (c) 0.005 to 0.05 moles of phosphorus pentoxide, (d) 0.03 to 0.2 moles of sodium oxide and (d) 0 to 0.05 moles of potassium oxide.

Abstract: A catalyst for the preparation of maleic anhydride by vapor phase catalytic oxidation of benzene with a molecular oxygen containing gas comprising a porous inert support of an alkali metal content, calculated as oxide, of at most 0.3 % by weight and supported thereon a catalytic substance of a constituent composition comprising (a) 1 mole of vanadium pentoxide, (b) 0.3 to 1.2 moles of molybdenum trioxide, (c) 0.005 to 0.05 moles of phosphorus pentoxide, (d) 0.03 to 0.2 moles of sodium oxide and (d) 0 to 0.05 moles of potassium oxide.