STAMP-VENDING MACHINES.

Stratford Evening Post, Volume IV, Issue 160, 18 June 1936, Page 8

STAMP-VENDING MACHINES.

! Annual Sales Worth £38,000 A, CLEVER APPLIANCE. The. extent to which Automatic ttainp-vendmg machines are.meeting the convenience of the public in New Zealand is demonstrated by the tact that last year £38,000 worth of penny stamps went out into circulation through the tiny slots of those devices, pulled out one by one by people who ha:l put in a penny'. It will be interesting to those who uisc the machine to learn something of its construction and method of •operatiou. They have pnibably discovered that the penny has to be pushed into the slot firmly, the reason being that sufficient pressure must be exerted to lift a light weight which, in its subsequent fall, provides (he power necessary to actuate the machine to the point of producing one stamp in return for the penny. There if a very simple, but cleverly designed, mechanism within the machine which prevents the stamp feed from working unless a bona fide ; penny has been inserted to start operations. Lead, discs, half crowns, and the circular tops of match boxes have been tried, the general result being that they are thrown out through the lowest slot on the face of the instrument.

But if a penny is inserted the mechanism works smoothly, revolving a small drum which carries tiny pins' fitting exactly into the perforations of the stamp. ,A slight pull by the intending purchaser enables the stamp which appears outside the slot to be detached from a continuous roll lying behind in the recess of the machine. Great accuracy is.needed in constructing the moving parts of the mechanism, the stamp drum t)eing machined to limits of l/OOOth*' of an inch. The preparation in the Government Printing Office of the stamp rolls, carrying 480 penny stamps involves the use of a specially designed machine.

Comparatively few complaints are received of the machines failing 'to function, a tribute to the excellence of the workmanship at the Department's workshops in Wellington where they are manufactured. Dampness has to be guarded against in machines! having very fine adjustments so as to avoid risk of failure or the gum on the stamps being affected, in some instances a lowpower electric light is kept burning inside the machine, but in the majority' of cases a small tin of powdered calcium chloride placed in the base ol the i machine is sufficient to extract tbe moisture from the air and enable the mechanism to function efficiently in all weathers.