GB190917177A - Improved Key. - Google Patents

Abstract

17,177. Harvey, H., and Harvey, H. July 23. Keys.-In a key provided with mechanism to show whether the bolt of the lock is shot or withdrawn, a sleeve c is mounted on the stem of the key and can rotate relatively thereto, such movement being limited by a pin f on the sleeve engaging a slot g in the barrel of the key, notches g<1> at each end of the slot serving to hold the sleeve at either end of its movement. The sleeve is under the control of a spring e within the key barrel and bearing on a plate d, to which the pin f is secured. When the key is inserted into the lock, the sleeve is pressed back to release the pin f from the notch g<1>, and, when the key is turned, the sleeve is caused to move from one position to the other by means of a projection j on the sleeve engaging a projection k on the casing. An aperture l in the sleeve reveals the words "open" or "closed" according to the position of the sleeve. In Fig. 9, the application of the invention is shown to a pin key. The spring e is in this case mounted on the key stem, and the projection j of the sleeve engages one of two notches in a fixed collar a<1> on the key. In the form shown in Fig. 6, the position of the pin j on the key barrel indicates the state of the jock, the pin being held in either of its two positions by means of a bayonet-slot m' in a spring- controlled piece m mounted in the key barrel.