Patent GB-190525296-A (GB)
Title: An Improved Watchman's Time Detector.
Inventor: MOOSMANN PAUL
Filed: 1905-12-05
Granted: 1906-12-05
Abstract: 25,296. Moosmann, P. Dec. 5. Tell-tales for checking watchmen. A time-checking apparatus, containing a clock-rotated dial D adapted to he marked by the insertion of keys K placed'at different parts of a watchman's round, has means for advancing a counting- wheel h<3> in the key at each actuation. This counter may be held in or out of action or be put out of action automatically after a predetermined time. A device for detecting the use of an imitation key is also provided. A marker e, carried by a spring E<2>, is depressed by a ward of a key K, and upon release strikes a clock-driven dial D placed in the other half of the case. The spring is carried by a slidable plate E<1> which also bears a guide-bracket e<1> for a spindle E over which the inserted key fits as it presses the bracket e<1> inwards. The inner end of this spindle is shouldered and engages a bracket on another slidable plate F guided by a pin and slot the two brackets being pressed apart by a spring. Inside the key is a spring-pressed screw h with a recessed end, which engages the tapered end of the spindle E and turns relatively to the key to advance the counter h', provided the second sliding plate F is held to ensure engagement between the spindle and screw. The plate carries on one pin two levers which are spring-pressed towards an antifriction roller i<1> on the case, the lower lever having two notches, one of which by engaging a pin as sbown in Fig. 1 prevents the plate from sliding. The other notch is adapted if desired to engage the roller i<1>, and the upper lever then projects into the path of a pin p on the dial D, which presses back'the upper lever and plate F and so disengages the counter at a definite time. Additional holding-pins for the dial are provided, and on extra pin which by puncturing the dial indicates the time of disengagement of the counter. The second sliding plate F can be held in either position by a pivoted piece r which can be turned to engage either of two notches. The bracket e<1> on the first sliding plate E<1> against which the key presses is slotted to receive the end of a wire spring g, Fig. 4, fastened to this plate, and the key ward strikes this end if turned back. When being turned forward and while depressing the spring plate E', it passes a hook w<1> which projects upwards from this sliding plate E<1> and prevents return ; the bracket may also be recessed for the same purpose. Continued turning brings the ward against the . back of the above-mentioned wire spring g, which is moved forward in its slot and allows withdrawal of the key, but prevents another actuation of the marker without withdrawal. Fig. 9 shows a device for indicating the attempted use of an imitation key with a short ward, and consists of a plate u having a flange u<2> over the edge of the spring E<2> and carried by a spring u<1>. Rotation of a short ward does not push this plate out of the way of the spring, whereby the flange prevents a mark from being made. At the same time, a point on the plate u makes a mark when pressed up by the spring E<2> and indicates the attempted fraud.