Abstract: A control device for a vending machine for setting prices and storing prices in a memory with a price-setting mode, a price verification mode and a product-vending mode. In the product-vending mode, actuation of a selection switch provides a momentary pulse through the vending circuit to enable a price to be loaded into a register for subsequent comparison with accumulated credit. That pulse is so short that a product is not vended; but it is sufficiently large to keep leakage from simulating it. Switches select the locations in memory where prices are stored, and further switches are provided to set the prices in those locations. The control device automatically responds to actuation of any of these switches to shift from the product-vending to the price-setting mode. Coin tube inventory switches are provided which have a dual function, namely, effecting emptying of the coin tubes and also placing the control device in the price verification mode.

Abstract: In the production of shaped silicon-carbide bodies, especially tubes which onsist predominantly of silicon carbide throughout their thickness for use in nuclear-reactor technology, a carbon-containing preform (body of the desired shape) is contacted with elemental silicon powder at a temperature of 1400.degree. C. to 1500.degree. C. and the silicon-contacted carbon-containing body is thereafter treated at a temperature of 1800.degree. C. to 2000.degree. C. to transform at least the major part of the carbon into silicon carbide.

Abstract: A portion of the feed gas is supplied in a pulsating fashion to a fluidized ed reactor containing the articles to be coated mixed with fluidizing particles. The pulse frequency is between 1 and 10 Hz. A continuous flow of a portion of the total gas supply at a rate insufficient to produce turbulence in the bed is provided to facilitate control of the pulsing frequency and reduce the energy necessary for the pulsating gas stream. The gases fed to the reactor are a coating gas and a carrier gas, the flow containing the coating gas including a portion of the carrier gas. Either the pulsed flow or the continuous flow may consist entirely of carrier gas. The fluidizing particles are preferably of the same material as the articles to be coated and are typically of a grain size between 2 and 3 mm.

Abstract: A circuit responds to a level-sensing device, adjacent a coin-holding tube, to cause an electric motor to rotate a coin-receiving drum until sufficient coins issue from that coin-receiving drum to fill that coin-holding tube. Ordinarily, coins will issue from that coin-receiving drum in such rapid succession that the motor need not be energized very long. However if, because some coins within that coin-receiving drum interact to form a "bridge" which retards or prevents the issuance of other coins from that coin-receiving drum, or if for any other reason coins do not issue from that coin-receiving drum, the circuit will keep that motor energized for a finite length of time, will de-energize that motor, and will energize that motor for a second finite length of time.