A method of manufacturing a bridge-type ball screw (1) with a bridge member (5) fit into a nut bridge window (6). The bridge member (5) has a linking groove (5a) with a rolling track that acts as a circulating path. After the bridge member (5) is fit into the nut bridge window (6), a cylindrical mandrel (8), with projections (9), is inserted into the nut (3). An upper die (10) restricts the upper surface of the bridge member (5) and is lowered while the nut (3) is held between the upper die (10) and the mandrel (8). A connection part is subject to plastic working by the projections (9) of the mandrel (8). The bridge member (5) is simultaneously deformed by the upper die (10) to secure the bridge member (5) into the nut bridge window (6).

A method of manufacturing a bridge-type ball screw (1) with a bridge member (5) fit into a nut bridge window (6). The bridge member (5) has a linking groove (5a) with a rolling track that acts as a circulating path. After the bridge member (5) is fit into the nut bridge window (6), a cylindrical mandrel (8), with projections (9), is inserted into the nut (3). An upper die (10) restricts the upper surface of the bridge member (5) and is lowered while the nut (3) is held between the upper die (10) and the mandrel (8). A connection part is subject to plastic working by the projections (9) of the mandrel (8). The bridge member (5) is simultaneously deformed by the upper die (10) to secure the bridge member (5) into the nut bridge window (6).

A ball screw is provided in which an outer circumferential formation is formed at a portion facing a ball circulating passage out of outer circumferential surface of a nut. The ball screw includes: a screw shaft having on its outer circumferential surface a screw groove; a nut having on its inner circumferential surface a screw groove facing the screw groove; a plurality of balls rollably loaded in a spiral ball rolling passage formed by both screw grooves; and a ball circulating passage to return the balls from a start point to an end point of the ball rolling passage for recirculation. The ball circulating passage is a concaved groove formed by concaving a groove on a part of the cylindrical inner circumferential surface of the nut by plastic working. Then, a flange is integrally provided at a portion facing the ball circulating passage and the screw groove.

A ball screw is provided in which an outer circumferential formation is formed at a portion facing a ball circulating passage out of outer circumferential surface of a nut. The ball screw includes: a screw shaft having on its outer circumferential surface a screw groove; a nut having on its inner circumferential surface a screw groove facing the screw groove; a plurality of balls rollably loaded in a spiral ball rolling passage formed by both screw grooves; and a ball circulating passage to return the balls from a start point to an end point of the ball rolling passage for recirculation. The ball circulating passage is a concaved groove formed by concaving a groove on a part of the cylindrical inner circumferential surface of the nut by plastic working. Then, a flange is integrally provided at a portion facing the ball circulating passage and the screw groove.

A molding die structure for forming oblique teeth on a rivet nut includes a mold seat, a first forging die, a second forging die, and a retaining member. The mold seat is provided with a mold cavity and a threaded portion. The first forging die is inserted into the mold cavity and provided with a die cavity and a nut cavity. The second forging die is inserted into the die cavity and has an inner face provided with an oblique toothed portion and a guide hole. The oblique toothed portion includes a plurality of oblique teeth. The retaining member is screwed into the threaded portion and limits the first forging die and the second forging die in the mold cavity. The second forging die and the die cavity of the first forging die form a low friction contact.

A molding die structure for forming oblique teeth on a rivet nut includes a mold seat, a first forging die, a second forging die, and a retaining member. The mold seat is provided with a mold cavity and a threaded portion. The first forging die is inserted into the mold cavity and provided with a die cavity and a nut cavity. The second forging die is inserted into the die cavity and has an inner face provided with an oblique toothed portion and a guide hole. The oblique toothed portion includes a plurality of oblique teeth. The retaining member is screwed into the threaded portion and limits the first forging die and the second forging die in the mold cavity. The second forging die and the die cavity of the first forging die form a low friction contact.

In order to optimize a nut and a method for the production of a nut, comprising a nut body which is provided or can be provided with an internal thread and has a polygonal section with a polygonal outer contour which has, on the one hand, edge areas and, on the other hand, key faces which are located between the edge areas and extend in key face planes extending in a manner conforming to standards, in such a manner that it has mechanical properties which are as ideal as possible with as low a weight as possible, it is suggested that the nut body have a plurality of recesses which extend into the nut body in the direction of the bore proceeding from the respective key face planes.

Space in a conduit having at least one cable therein which is surrounded by a duct is recovered by longitudinally cutting the duct and removing the duct from around the cable. The duct may be pulled out of the conduit and past a blade to affect the cutting, or a blade may be pulled through the conduit to cut the duct while still in the conduit.

A method of manufacturing a nut integrated with a bracket forms the nut formed integrally with the bracket or a slab base nut by using a plate material supplied between a punch and a die. The slab base nut includes a base plate and a boss extending from the base plate and including female-threads. The base plate and the boss are integrated into a single piece without welding trace.

A method of manufacturing a nut integrated with a bracket forms the nut formed integrally with the bracket or a slab base nut by using a plate material supplied between a punch and a die. The slab base nut includes a base plate and a boss extending from the base plate and including female-threads. The base plate and the boss are integrated into a single piece without welding trace.