Abstract: A low cost differential voltage limiter circuit provides a feedback to regulate a voltage output of a voltage source. In one embodiment, the limiter circuit includes a transistor coupled to outputs of first and second voltage sources. If a differential voltage between the two sources exceeds a predetermined threshold, the output voltage of the higher source is reduced. In one embodiment, a PNP transistor is used to regulate the high voltage source.

Abstract: There is provided an inflatable cushion filling machine for forming inflated packaging cushions from a roll of tubular thermoplastic material. The machine includes a film supply section and a cushion forming section. The cushion forming section includes means for delivering the tubular material through the cushion forming section; means for applying tension to the web of tubular material while air is being introduced into the tubular material. Means are provided for introducing air into the area between the tension means to fill the cushion. When filled, a sealing band, displaced transversely across the inflated tubular thermoplastic material, seals the lower end to form the top of one cushion and the bottom of the next cushion. Prior to forming the cushion, the walls of the tubular material separate from each other by the residual air from the filling operation of the previous cushion. A perforation knife may be provided to separate each cushion from the next succeeding cushion.

Abstract: A clamping system for a fluid injection gun and cartridge such as the type in which fluid foam precursors are fed to the cartridge to be mixed and distributed to make custom foam packaging. The clamping system comprises a valve that defines respective opened and closed positions, a clamp seat adjacent the valve for receiving an injection cartridge therein, a clamp lid engagable against the seat and movable between respective open and closed positions, a finger on the valve for preventing the clamp lid from being opened while the valve is open to thereby prevent the clamp lid from being opened when fluid is flowing through the valve, and a shoulder on the clamp lid for preventing the valve from being opened when the clamp lid is opened to thereby prevent the flow of fluid when the lid is open.