Abstract: A retractor is provided with a detector for the amount of a webbing wound on a retractor shaft. The detector is of the type that the amount of the webbing wound on the retractor shaft is determined on the basis of the number of revolutions which the retractor shaft has undergone. The retractor includes first and second internal gears, at least one planetary gear and a switch actuator. The first and second internal gears have different numbers of teeth, and are arranged side by side in the direction of an axis of the retractor shaft. The first internal gear is fixed on the base while the second internal gear is rotatably supported on the base. The planetary gear is provided on the retractor shaft and is maintained in meshing engagement with both the first and second internal gears. A switch actuator is formed on the second internal gear and a switch is provided on the base.

Abstract: A translation element, a so-called driving dog or transmitter, for translating the rotation of the center of gravity of an excentrically mounted excentric gear wheel (9) to a first shaft (14) when said wheel simultaneously executes a planetary movement about a second shaft. A rigid body (10,25) which is pivotably mounted about first pins (11, 12) has axially directed, tooth-like projections (26, 27) fitting with negligible play into two radially counter-directed apertures (22, 23) in said wheel (9) for permittinhg said projections to execute a radial reciprocally gliding motion in the apertures, simultaneously as they execute a rolling motion in said apertures, while the rigid body pivots about the first pins.

Abstract: The production of differential speed reduction apparatus, which uses a double-toothed gear including face cams having tooth profiles uniquely generated to secure efficient speed reduction. The speed reduction apparatus includes an input shaft carrying the double-toothed gear, a slant shaft wobbling in association with the rotation of the input shaft, a stationary face gear engageable with the face cams, a movable face gear secured to an output shaft, wherein the stationary face gear and the movable face gear have a roller-like or a convex-face contour.

Abstract: A reclining angle adjustment device for a seat includes a shaft having a concentric portion and an eccentric portion and rotatable for adjusting the reclining angle of the seat, a tapered bushing having a tapered inner peripheral surface engaging the eccentric portion along the shaft, a gear train including an external gear and an internal gear meshing with the internal gear, the internal gear having more teeth than the external gear, a first arm having one of the external and internal gears which is rotatably fitted at its center over the concentric portion, and a second arm having the other gear which is rotatably fitted at its center over the tapered bushing. A resilient member normally presses the tapered bushing axially of the shaft in a direction to strengthen meshing engagement between the external and internal gears.

Abstract: A mechanical differential is disclosed. The mechanical differential comprises first, second and third ring gears, each having inner and outer surfaces, and first and second planet gears and two carrier rods. The first and second planet gears and first and second carrier rods are disposed within the ring gears. The first and second planet gears are engaged with the inner surface of the first ring gear. The mechanical differential further comprises two sets of planet gears, each of the sets including third and fourth planet gears. One of the sets is rotatably disposed on a third carrier rod and the other of the sets is rotatably disposed on a fourth carrier rod. The two sets of third and fourth planet gears are engaged respectively with the second and third planet gears. The two third output planet gears are further engaged with the inner surface of the second output ring gear and the two fourth planet gears are further engaged with the inner surface of the third ring gear.

Abstract: A planetary reduction gear has an inscribe type planetary gear mechanism (100; 600) and a planetary gear mechanism (130; 630) combined therewith. The inscribed type planetary gear mechanism has an internally-toothed gear (108; 602) and a flange (115; 608) either one of which serves as an output member while the other serves as a stationary member. Rotation of the input shaft (131; 631) of the planetary gear mechanism is transmitted to a planet carrier through an externally-toothed sun gear (132; 635) and planet gears (133; 636) so as to rotate the planet carrier in the same direction as the direction of rotation of the input shaft. The rotation of the planet carrier is transmitted to the output member through at least one eccentric member (102a, 102b; 61a, 613b) and at leat one externally-toothed gear (103a, 103b; 601b) in the inscribe type planetary gear mechanism so that the output member is rotated in the direction counter to the direction of rotation of the planet carrier.