GB1292552A - A synchronous alarm clock - Google Patents

Abstract

1292552 Alarm clocks K DIEHL 17 Dec 1970 [27 Dec 1969] 59852/70 Heading G3T In a synchronous alarm clock in which a mechanical oscillator 24 is electro-magnetically excited to sound the alarm when a blocking tappet 22 is removed therefrom, the alarm blocking/release mechanism comprises a lever 18 which is pivoted on a pin 21 and may be actuated by an alarm control drum 8, a stop member 30, or a repeat (drowse) button 44. A spring 20 on the tappet 22 normally biases the lever 18 so that one end 19 thereof is in contact with the control drum 8. The latter is rotated once every twentyfour hours on a spindle 10 upon which it is axially displaced when its apertures 14, 15 become aligned with lugs 12, 13 on an alarm setting wheel 11. The end 19 of the lever 18 normally rides on a cylindrical surface of the drum 8, Fig. 2, but during axial displacement of the drum, the end 19 slips down a conical surface of the drum, Fig.3, allowing the other end 23 of the lever to rise. The oscillator 24 is thus permitted gradually to approach excited magnetic poles 26, 27, producing an alarm signal of increasing intensity. To cancel the alarm the stop member 30 is pushed in against a spring (35), Figs. 4-6 (not shown), so that a cone 32 depresses the lever end 23 which becomes latched on the rear surface of the cone. The alarm is automatically reset by a cam 34 on the drum 8 which raises the end 19 of the lever 18 and unlatches the member 30 which is returned by its spring (35). Permanent cancellation of the alarm may be obtained by turning the member 30 through 90 degrees so that a surface 28 or 29 thereon holds down the lever end 23. A repeat alarm signal after a drowse interval may be obtained by depressing the button 44 so as to rotate a lever 39 whereby a tab 40 thereon depresses the lever 18 while an arm 47 on a further lever 46, which is hinged to the lever 39, is pressed by a spring 48 into latching engagement with the teeth of a minute wheel 6. As the wheel 6 rotates, the lever 18 and oscillator 24 are gradually released. Depression of the button 44 also unlatches the member 30 if the latter has been pushed in. In an alternative embodiment, the alarm repeat mechanism is actuated by depressing the clock housing (50), Fig.7 (not shown), against the force of a spring (70), the housing (50) being hinged to a base plate (51).