Abstract: A powder conveying pump, in particular for a powder coating device. The pump comprises a working chamber with a variable working chamber volume, a powder inlet opening into the working chamber to suck powder into the working chamber, a powder outlet opening out of the working chamber to expel the powder present in the working chamber and a moveable piston that forms one boundary surface of the working chamber and sucks the powder into the working chamber through the powder inlet during an upward movement. The piston is driven directly by pneumatic means.

Abstract: A powder transfer pump to convey a powder, in particular in a powder coating station. The powder transfer pump comprises a transfer chamber with a transfer chamber wall, an inlet opening into the transfer chamber to supply the powder to the transfer chamber, an outlet opening out of the transfer chamber to convey the powder from the transfer chamber, a negative pressure connection opening into the transfer chamber to generate negative pressure in the transfer chamber in order to suck the powder into the transfer chamber, and a positive pressure connection opening into the transfer chamber to discharge the powder that is present in the transfer chamber through the outlet. The transfer chamber wall is essentially gas-tight.

Abstract: An operating system for a power feed pump and a power feed pump having a transfer chamber with an inlet and an outlet. The outlet of the transfer chamber is closed, the inlet of the transfer chamber is opened, and a negative pressure is generated in the transfer chamber to suck a powder in through the inlet to the transfer chamber. The inlet of the transfer chamber is closed, the outlet of the transfer chamber is opened, and the powder in the transfer chamber is delivered through the outlet. The negative pressure in the transfer chamber is built up at least partially before the inlet of the transfer chamber is opened.