GB305267A - Improvements in or relating to coin-freed vending machines - Google Patents

Abstract

305,267. Fiala, A. K. Nov. 4, 1927. Magnetic apparatus.-A coinfreed vending machine is provided with a magnetic recording and reproducing device, such as a Poulsen telegraphone, which is in operative connection with the coin insertion or other mechanism of the machine so as to cause a loud speaker to deliver an audible announcement whenever the machine is brought into use. The announcements may be repeated or changed as desired. The text spoken into a microphone 2, Fig. 1, is impressed on a rotating steel disc 1, when the arm 12 of a switch 13 is on a contact 14, by a small electromagnet 11 carried by a lever arm 36 which is moved radially over the disc. Current is supplied from batteries 3, 4 in series, through a low-frequency transformer 5, 6. The negative pole 9 of the battery 4, one end 7, 8 of each of the primary and secondary coils of the transformer, and one end of the magnet coil 11 are all earthed. The circuit of the batteries is provided with a cam switch 10 which is closed only when the disc 1 is rotating. The magnet 11 is carried by a leaf spring 35 detachably secured to the lever 36, and the recording and reproducing point of its core 33 is protected by solder 43 from wear. In order to eliminate disturbing subsidiary noise, a thin layer 44 of magnetically inactive material, such as paper, celluloid and the materials sold under the registered Trade Marks " Cellon," " Cellophane." is interposed between the disc 1 and the point of the magnet 11. The text is obliterated, when an alteration is desired, by moving the switch arm 12 to a contact 17 and traversing the magnet 11 over the disc 1. For reproduction, the switch arm 12 is moved to a contact 19, and the switch 26, 27 of a threevalve amplifier is closed. The magnet 11 now acts as a pick-up and the amplified acoustic currents are reproduced on a loud speaker 24<1>.