Sicherheitsschloss

摘要

1,123,746. Safety latches. A. S. MARTI, J. S. MARTI, J. S. MARTI, and M. S. MARTI. 31 Aug., 1966 [11 May, 1966], No. 38941/66. Heading E2A. A safety latch comprises a knob consisting of two semi-spherical parts 1, the rear part 17 being united to a disc 18 provided with indicia indicative of angular position with reference to a reference mark on a fixed circular plate and having a sleeve 19 connected to a hollow cylindrical shaft 22 with an external groove for the accommodation of parts of the mechanism of a combination the hollow shaft having a coaxial internal shaft 2 connected to the part 1 of the knob and terminating in a screw thread the end portion of the sintered shaft 2 engaging in a disc 5 with a radial lever the end of which engages in a recess in a plate connected to a bolt 21 slidable in a latch case. The bolt 11 is urged outwardly by a spring and has a rearward projection, which is engageable in notches in three coaxial stop wheels 25A, 25B, 25C freely rotatable on a shaft 34 displaceable in the case. The stop wheel are rotated to block operation of the bolt by freeing three wheels 24A, 24B, 24C in mesh with the stop wheels and freely rotating on shaft 22, from spring urged pivoted catches; auxiliary wheels in mesh with the wheels 24A, 24B, 24C rotate the stop wheels under the action of a tensioned spring. To set the combination for blocking latch withdrawal, with the bolt in latching position and the bolt projection aligned with the notches in the stop wheels, the shaft 34 is displaced in the case to disengage the stop wheels from the wheels 24A, 24B, 24C. The knob 17 is set so that the mark I on the disc 18 coincides with the reference mark on the plate then by rotating the knob to and fro about this position, the movement being limited by a tooth on a cam 41 on the shaft 22 abutting a tooth on a pivoted lever 47, the wheel 24A is indexed by the tilting of a flattened surface on a cam 27A on the shaft against a pivoted lever 29A with a catch engaging tooth on the wheel 24A thereby rotating an auxiliary wheel and tensioning a spring secured thereto and to the case. The knob 17 is successively turned through 90‹ so that marks II and III coincide with the reference mark and the knob is rotated to and fro in each position to tension the springs of the two other auxiliary wheels in mesh withwheels 24B, 24C. When the shaft 34 is restored to its original position so that the wheels are in mesh the bolt 11 can be withdrawn by rotating the knob part 1. To prevent withdrawal the knob 17 is rotated a further 90‹ thereby disengaging the catches on the levers 29A, 29B, 29C from the wheels 24A, 24B, 24C and an arm on the end of the lever 47 releases the spring urged pivoted catches from the wheels which are free to rotate the stop wheels under the action of the tensioned springs on the auxiliary wheels. The notches in the stop wheels are moved out of alignment with the projection on the bolt thus preventing its withdrawal. The notches are realigned by resetting the combination.