TO WIND ITSELF.

Press, Volume LXIII, Issue 18917, 4 February 1927, Page 4

TO WIND ITSELF.

NEW CAR CLOCK. The winding of one's watch is seldom forgotten. It is part of the routine of going to bed, and, therefore, takes' place at regular intervals. Not so the clock on the dashboard of a car, taken otit at odd times; and tho frequency with which such clocks stop because the owners hnvo forgotten t°) wind them is astonishing. A car clock, says "Chambers* Journal," can now be obtained which winds itself, so far as any attention on tho part of the owner is concerned. In reality it is wound by electric current from the lighting battery. Moreover, it is continually maintained in the fully-wound condition, the electric device acting at tho first tooth of the winding ratchet. This feature promotes good time-keeping, since the strength of the spring is always the same. The winding is done as follows: Tho unwinding movement makes an electric contact at one-minute intervals, which passes current through an electro magnet. The result is that .*>n iron armature i» drawn up to the poles, and this movement winds up the spring one "click" of a ratchet wheel. At the same time the contact is broken; and immediately after tho armature has done its work it is pulled back br a spring, ready for the next wind. "The current. .05 at 12 volts, is on onlv for a fraction of a second, so that the demand on the battery is almost infinitesimal. A small hand at. the bottom of the clock dial shows the

rewinding movement, as it takes place. The time-keeping movement is of a high-grade type, and the clock is of a standard size to suit the opening in the dashboard. The onl.v addition needed consists of the two wires for supplying the current, while the clock may bo hand-wound like any other during a prolonged absence of the battery.