FR2251051A1 - - Google Patents

Abstract

1482449 Frictional detents; band brakes T SESSA 17 Oct 1974 [9 Nov 1973] 45128/74 Heading F2E [Also in Division E2] A driving shaft 10 of a vehicle window is braked in its directions of rotation F, F1 corresponding to raising and lowering of the mobile upper part of the window by a spring 12 comprising two parts 13, 14 interconnected by a bridge 15; the coils of portion 13 are adapted to rest under preload against the shaft 10 to apply a braking action thereto while the coils of portion 14 are loose on the shaft 10, the ends 16, 17 of the respective spring portions 13, 14 and the bridge 15 being co-operable with abutment forming shoulders 18, 19 on a housing 11 of the shaft 10 to control the action of the spring 12. When the shaft 10 is rotated in a clockwise direction F, corresponding to upward movement of the upper mobile window part the bridge 15 engages against the shoulder 19, to concel the torque which spring portion 14 applies to portion 13 so that shaft 10 can freely rotate. When the shaft 10 is rotated in the anticlockwise direction F1, the spring portion 13 remains locked on shaft 10 and rotates therewith until its end 16 engages shoulder 18 to thereafter cause the spring portion 13 to loosen and portion 14 to partially tighten around shaft 10 to brake the descent of the window part. When the shaft 10 ceases rotation the system returns to the equilibrium position indicated in Fig. 3 (not shown). Figs. 5-8 illustrate a practical application wherein shaft 10 which is rotated by pinions 23 is of square cross-section and the spring 12 is mounted on a sleeve 32 of square inner crosssection and circular outer cross-section mounted on the shaft 10. A normal torsion spring 28 designed to balance the weight of the mobile part of the window is also provided.