Patent GB-220335-A (GB)
Title: Improvements in mechanism controlling alarms in clocks
IPC: G04B23/08
Filed: 1923-12-17
Abstract: 220,335. Newth. B., and Newth, O. Dec. 19, 1922, [Convention date]. Alarm and like mechanism.-In an alarm clock the movement of which is maintained for a relatively long period, means are provided for automatically stopping and resetting. The alarm bell, Fig. 4, is screwed to a. sleeve on the arbor of the minute hand, said sleeve being held in place by a milled nut 36, which is adapted for hand setting in the usual way. The alarm-bell circuit is closed once in 24 hours bv a contact lever 88, Fig. 5, fast on the spindle of a lever 85 having a stud riding in a disc 74 which allows movement to close the contact 88, 90 once in 12 hours. In the alternate a.m. or p.m. periods contact is prevented by the lever 107 which has an extension engaging the pin 109 on the lever 85. The lever is rocked into the operative and inoperative positions by a spring-controlled toe 105 on a lever 102 which engages alternately one of a pair of recesses in the lever once in every 12 hours. The lever 102 is on the same pivot as the lever 85, and is allowed to rock under a spring by a pin 101 and a recess on the disc 75 rotating with the hour-hand, so as to allow contact 88, 90, and subsequently to break contact by raising the pin 84 from the disc 74. To set the alarm for a.m. or p.m. ringing, the lever 107 is operated by a forked lever 111 on the spindle 112 and a handle under the alarm bell. An indicator 115 shows the setting through an opening in the dial. To prevent the alarm ringing, the indicator 115 has a stud which may be moved against the extension 119 of the lever 85 to prevent movement thereof, the indicator then showing the word " off." For the daily control of the alarm, a spring-pressed lever 120 has an inclined part actuated by a sliding piece 122 on a stem 123, with an attached push-piece outside the case and within the pick-up ring. This lever is adapted in one position to engage the stud 109 and prevent the contact 88, 90. The push-down stud 123 is automatically restored to its normal raised position on the next operation of the lever 102 through an intermediate lever 126 which is raised against the stud. Attached to the push down rod 123 is an indicator showing the words " on " or " off " according to the disposition of the lever. The alarm is set by rotating the flanged wheel 42 frictionally held on the hour-hand arbor and provided with the integrally formed recessed discs 74, 75. The front disc 71 of the flanged wheel 42 has a setting dial to read against a pointer 72 on the hour hand. The rotation of the wheel 42 is effected by an integrally-formed toothed wheel 73, an intermediate wheel riding in slotted bearings, the wheels 77, 79, and spindle 78 which are driven by left-hand rotation of the bell with its screwed sleeve and fast pinion 81 through an intermediate wheel. The wheel 42 rotates with the hour hand, the intermediate wheel riding in its slotted bearings out of engagement with the wheel 77. Right-hand rotation of the bell screws it off the sleeve to give access to the various adjustments beneath, a counter-pawl preventing rotation of the wheel 81.