Abstract: Disclosed is a bracket angle adjustment mechanism adapted to reduce shock to be given to a wedge member, based on an improved wedge shape. The bracket angle adjustment mechanism comprises a pair of wedge members (16A, 16B). In each of the wedge members (16A, 16B), an arc-shaped outer surface (16a) has a diameter slightly less than that of an arc-shaped inner peripheral surface of a large-diameter hole (14c) of an external-tooth gear (14), and an arc-shaped inner surface has a diameter slightly greater than that of an arc-shaped outer peripheral surface of a small-diameter shank (15c) of an internal-tooth gear (15). The arc-shaped inner surface (16b) has a circumferential length approximately equal or greater than that of the arc-shaped outer surface (16a).

Abstract: An automobile seat includes a seat cushion, a seat back tiltably mounted on the seat cushion, and a head rest mounted on an upper portion of the seat back. The automobile seat also includes a seat cushion frame, a pair of side frames mounted on the seat cushion frame, and a seat back frame mounted on the pair of side frames so as to be rockable within a limited range of angle. The seat further includes a seat back frame rocking mechanism for causing, when an acceleration greater than a predetermined value is inputted from behind a vehicle body, the seat back frame to undergo a rocking motion, and a rocking motion preventing member for preventing, when the acceleration greater than the predetermined value is not inputted from behind the vehicle body, the seat back frame rocking mechanism from causing the seat back frame to undergo the rocking motion.

Abstract: A bracket angle adjustment mechanism has two wedge members (16A, 16B) fit in an eccentric space between a large-diameter hole (14c) of an external-tooth gear (14) and a small-diameter shank (15c) of an internal-tooth gear (15), and a wedged-state release member (19) is held by the external-tooth gear (14) so that an outer peripheral surface of the wedged-state release member (19) is fit rotatably into the large-diameter hole (14c). The wedged-state release member (19) has a clearance groove (19a) for avoiding interference with the wedge members (16A, 16B), a wedged-state release portion (19e), and a noncircular mounting hole (19d) non-rotatably fit with a attaching portion of a control shaft (20) penetrating through the small-diameter shank (15c) in a non-fitting manner. The bracket angle adjustment mechanism achieves enhanced strength and lower production cost, based on the improved mounting position of the wedged-state release member.

Abstract: Disclosed is a bracket angle adjustment mechanism which includes external-tooth and internal-tooth gears having improved tooth shapes allowing an operating force for rotating a control shaft to be reduced. In the bracket angle adjustment mechanism, each of external teeth (14b) of the external-tooth gear 14 has a half-round shape having a center defined by a single point “a” on a reference circle PC (14), in a region of an addendum T1 between the reference circle PC (14) and a tip circle AC (14), and an undercut shape in a region of a dedendum T2 between the reference circle PC (14) and a root circle DC. Further, each of internal teeth (15b) of the internal-tooth gear (15) has an arc shape free of interference with the half-round-shaped addendum region.

Abstract: An automobile seat includes a seat cushion, a seat back tiltably mounted on the seat cushion, and a head rest mounted on an upper portion of the seat back. The automobile seat also includes a seat cushion frame, a pair of side frames mounted on the seat cushion frame, a seat back frame mounted on the pair of side frames so as to be rockable within a limited range of angle, a seat back frame rocking mechanism for causing, when an acceleration greater than a predetermined value is inputted from behind a vehicle body, the seat back frame to undergo a rocking motion, and a rocking motion preventing member for preventing, when the acceleration greater than the predetermined value is not inputted from behind the vehicle body, the seat back frame rocking mechanism from causing the seat back frame to undergo the rocking motion.

Abstract: An automobile seat includes a seat cushion frame, a side frame, and a seat back frame mounted on the side frame to be rotatable within a limited angle. An elastic member and a guide portion having an elastic member holding portion are mounted on the side frame and the seat back frame. The seat back frame is normally fixed to the side frame with the elastic member held in the holding portion, but when a load greater than a predetermined value is inputted from behind, a lower portion of the seat back frame is pushed rearward by a lumbar part of a seat occupant to thereby deform the elastic member, which in turn leaves the holding portion and moves rearward along the guide portion, thus causing the seat back frame to rotate with respect to the side frame and causing the headrest to move forward.

Abstract: Disclosed is a bracket angle adjustment mechanism which includes external-tooth and internal-tooth gears having improved tooth shapes allowing an operating force for rotating a control shaft to be reduced. In the bracket angle adjustment mechanism, each of external teeth (14b) of the external-tooth gear 14 has a half-round shape having a center defined by a single point “a” on a reference circle PC (14), in a region of an addendum T1 between the reference circle PC (14) and a tip circle AC (14), and an undercut shape in a region of a dedendum T2 between the reference circle PC (14) and a root circle DC. Further, each of internal teeth (15b) of the internal-tooth gear (15) has an arc shape free of interference with the half-round-shaped addendum region.

Abstract: A bracket angle adjustment mechanism has two wedge members (16A, 16B) fit in an eccentric space between a large-diameter hole (14c) of an external-tooth gear (14) and a small-diameter shank (15c) of an internal-tooth gear (15), and a wedged-state release member (19) is held by the external-tooth gear (14) so that an outer peripheral surface of the wedged-state release member (19) is fit rotatably into the large-diameter hole (14c). The wedged-state release member (19) has a clearance groove (19a) for avoiding interference with the wedge members (16A, 16B), a wedged-state release portion (19e), and a noncircular mounting hole (19d) non-rotatably fit with a attaching portion of a control shaft (20) penetrating through the small-diameter shank (15c) in a non-fitting manner. The bracket angle adjustment mechanism achieves enhanced strength and lower production cost, based on the improved mounting position of the wedged-state release member.

Abstract: Disclosed is a bracket angle adjustment mechanism adapted to reduce shock to be given to a wedge member, based on an improved wedge shape. The bracket angle adjustment mechanism comprises a pair of wedge members (16A, 16B). In each of the wedge members (16A, 16B), an arc-shaped outer surface (16a) has a diameter slightly less than that of an arc-shaped inner peripheral surface of a large-diameter hole (14c) of an external-tooth gear (14), and an arc-shaped inner surface has a diameter slightly greater than that of an arc-shaped outer peripheral surface of a small-diameter shank (15c) of an internal-tooth gear (15). The arc-shaped inner surface (16b) has a circumferential length approximately equal or greater than that of the arc-shaped outer surface (16a).

Abstract: An automobile seat includes a seat cushion and a seat back tiltably mounted on the seat cushion. The automobile seat also includes a seat cushion frame, a side frame mounted on the seat cushion frame, a seat back frame mounted on the side frame so as to be rotatable within a limited angle, and a fastening member mounted on the seat back frame. The side frame has an insertion hole defined therein in which the fastening member is inserted and also has an impact absorbing structure. When a load greater than a predetermined value is inputted to the seat from behind, a lower portion of the seat back frame is pushed upon a rearward movement of a seat occupant to thereby cause the fastening member to move rearward while deforming the impact absorbing structure. As a result, the seat back frame rotates with respect to the side frame, and an impact is absorbed by deformation of the impact absorbing structure.

Abstract: An automobile seat includes a seat cushion and a seat back tiltably mounted on the seat cushion. The automobile seat also includes a seat cushion frame, a side frame mounted on the seat cushion frame, a seat back frame mounted on the side frame so as to be rotatable within a limited angle, and a fastening member mounted on the seat back frame. The side frame has an insertion hole defined therein in which the fastening member is inserted and also has an impact absorbing structure. Where a load greater than a predetermined value is inputted to the seat from behind, a lower portion of the seat back frame is pushed upon a rearward movement of a seat occupant to thereby cause the fastening member to move rearwards while deforming the impact absorbing structure. As a result, the seat back frame rotates with respect to the side frame, and an impact is absorbed by the deformation of the impact absorbing structure.

Abstract: An automobile seat includes a seat cushion frame, a side frame mounted on the seat cushion frame, and a seat back frame mounted on the side frame so as to be rotatable within a limited angle. An elastic member is mounted on one of the side frame and the seat back frame, while a guide portion having a holding portion for holding the elastic member is formed on the other of the side frame and the seat back frame, the guide portion. The seat back frame is fixed to the side frame in a normal sitting condition in which the elastic member is held in the holding portion.