Abstract: A driving force transmission device includes an input section and an output section with rotation axes nonparallel to each other to avoid backlash. A driving force transmission device (1) includes a first rotator (2), a second rotator (3), and spheres (5A, 5B, 5C). The first rotator (2) performs one of an input operation and an output operation of a driving force and includes a concave surface (7). The second rotator (3) performs the other of the input operation and the output operation of the driving force and includes a convex surface (13) fitted into the concave surface (7). The spheres (5A, 5B, 5C) are between the concave surface (7) and the convex surface (13). The concave surface (7) has holes (32A, 32B, 32C) in which the respective spheres (5A, 5B, 5C) are received. The convex (13) surface has a groove (29, 30) that receives parts of the spheres (5A, 5B, 5C) protruding from the holes (32A, 32B, 32C).

Abstract: A driving force transmission device includes an input section and an output section with rotation axes nonparallel to each other to avoid backlash. A driving force transmission device (1) includes a first rotator (2), a second rotator (3), and spheres (5A, 5B, 5C). The first rotator (2) performs one of an input operation and an output operation of a driving force and includes a concave surface (7). The second rotator (3) performs the other of the input operation and the output operation of the driving force and includes a convex surface (13) fitted into the concave surface (7). The spheres (5A, 5B, 5C) are between the concave surface (7) and the convex surface (13). The concave surface (7) has holes (32A, 32B, 32C) in which the respective spheres (5A, 5B, 5C) are received. The convex (13) surface has a groove (29, 30) that receives parts of the spheres (5A, 5B, 5C) protruding from the holes (32A, 32B, 32C).

Abstract: A pinion (1) including a pin gear allows easy engagement with or disengagement from a mating gear. The pinion (1) includes a plurality of pins (2) as teeth, and includes a first plate (4) and a second plate (5) described below. The first plate (4) interconnects first ends of the pins (2). The second plate (5) is spaced from the first plate (4) in the rotation axis direction of the pinion (1), and interconnects second ends of the pins (2). The second plate (5) has, on its outer peripheral edge, recesses (15, 16) each between two pins (2) adjacent circumferentially. The recesses (15, 16) recede inward from inner circumferential ends of the pins (2). The pinion (1) is moved axially for engagement with or disengagement from the rack (3). The pinion (1) increases flexibility at the time of engagement with or disengagement from a mating gear.

Abstract: In a self-lubricating transmission device 1, a compression helical spring 15 is provided to urge an impregnation metal 14 as an impregnation means so as to slidably contact the impregnation metal 14 with pin rollers 7. In combination with a rotational movement of a pinion 6, the pin rollers 7 slide on a lower surface 14d of the impregnation metal 14 to supply a lubrication oil W to the pin rollers 7 so as to automatically lubricate the pinion 6 evenly at the right time for an appropriate amount of the lubrication oil W. This obviates the lubrication oil W being wastefully used, while at the same time, making a lubrication work quick, labor-saving and user-friendly.

Abstract: In a rack extension jig device 9, a protracted direction E of tooth projections 12-14 and an elevational direction H of racks 7, 8 are placed in a coplanar position G. This makes it possible to positively engage the tooth projections 12-14 with the respective rack teeth 7, 8 and half tooth surfaces 7c, 8c so as to set a predetermined pitch interval T at a contact portion between the neighboring racks 7, 8 by only pushing the tooth projections 12, 13, 14 against roots 7d, 8d of the respective rack teeth 7, 8 in perpendicular to the roots 7d, 8d, thereby making a rack-adding work easy, quick and user-friendly.

Abstract: In a self-lubricating transmission device 1, a compression helical spring 15 is provided to urge an impregnation metal 14 as an impregnation means so as to slidably contact the impregnation metal 14 with pin rollers 7. In combination with a rotational movement of a pinion 6, the pin rollers 7 slide on a lower surface 14d of the impregnation metal 14 to supply a lubrication oil W to the pin rollers 7 so as to automatically lubricate the pinion 6 evenly at the right time for an appropriate amount of the lubrication oil W. This obviates the lubrication oil W being wastefully used, while at the same time, making a lubrication work quick, labor-saving and user-friendly.

Abstract: In a rack extension jig device 9, a protracted direction E of tooth projections 12-14 and an elevational direction H of racks 7, 8 are placed in a coplanar position G. This makes it possible to positively engage the tooth projections 12-14 with the respective rack teeth 7, 8 and half tooth surfaces 7c, 8c so as to set a predetermined pitch interval T at a contact portion between the neighboring racks 7, 8 by only pushing the tooth projections 12, 13, 14 against roots 7d, 8d of the respective rack teeth 7, 8 in perpendicular to the roots 7d, 8d, thereby making a rack adding work easy, quick and user-friendly.