GB808025A - Link mechanism actuated by pivoted lead screw having a plurality of nuts thereon - Google Patents

Abstract

808,025. Screw-and-nut gearing. AMERICAN METAL PRODUCTS CO. Dec. 6, 1955 [April 18, 1955], No. 34997/55. Class 80 (3). [Also in Group XIV] A screw and nut mechanism for operating two separate means either independently or together is particularly applied to the power operation of the raising and lowering, and forward and backward movement, of a vehicle seat. A screw 31, reduction gear 29 and a motor 28 are pivoted as a unit about a pivot 32 and a pair of nuts 34, 35 each having a holding device operated by a solenoid 37 co-operate with the screw. The nut 34 is pivotally connected at 38 to the arms 14 of a rock shaft 12 which operates through an arm 16 and a link 17, a bell crank 6, and through a link 19 a further bell crank (not shown) at the other end of the mechanism. The bell cranks 6 are coupled to brackets 8 secured to the seat slide 9 for raising and lowering the same on actuation of the nut 34 by the screw. The nut 35 is pivotally connected at 39 to two links 42 coupled to arms 15 of a rock shaft 13 which operates through an extension 22 of one arm 15 a link 23 coupled to a bracket 24 to the sliding seat frame 11. Thus the seat frame is slid backwards or forwards on actuation of the nut 35 by the screw 31. The pivotal mounting of the screw and driving unit and the link connection 42 to one nut allow the free operation of either or both of the nuts. A third nut may be provided on the screw for operating mechanism for tilting the seat. The nuts 34 and 35 rotate freely with the screw when not held by the solenoids 37 and do not then transmit movement to the operating mechanisms. When the solenoids are operated the nuts are held to transmit the desired movement. The nuts may be released by limit devices at their limits of travel or by overload devices. The mechanism is stated to be also applicable to operating the ventilating and vertically movable windows of a vehicle door.