Abstract:
Transport system with several devices (1) for transporting powder, where each device (1) has a transfer chamber (3) into which a supply line (6) and a discharge line (8) for the powder open, and means to generate a negative pressure in the transfer chamber (3), where the means to generate a negative pressure in the device (1) has a piston (11) which is moveable in the transfer chamber.
Abstract:
In a piston metering pump for supplying the atomizer of a powder coating machine, the vacuum generated in the pump chamber during the suction movement of the piston is reduced in controlled fashion by introducing transport air in order to reduce the powder throughput.
Abstract:
Apparatus for pumping a powdery or granular material has a first cylinder and a second cylinder parallel to each other and each having a front end and a rear end, a connector box connecting the respective rear ends of the cylinders for placing them in communication, a material inlet at the front end of the first cylinder, a material outlet at the front end of the second cylinder, a first piston in the first cylinder and a first piston rod connected thereto and extending out of the first cylinder, a second piston in the second cylinder and a second piston rod connected thereto and extending out of the cylinder, and a reciprocating drive connected to the piston rods for reciprocating the pistons simultaneously in the same directions within the respective cylinders, the pistons each having openings therethrough and a first one-way valve on the first piston normally closing the opening therein and opening when the first piston is moving in the forward direction and a second one-way valve on the second piston normally closing the opening therein and opening when the second piston is moving in the rearward direction.
Abstract:
A powder conveying device for the conveying of coating powder to a powder applicator includes a working container that is designed and operable appropriately such that it can be pressurized. The working container further includes a powder inlet and a powder outlet, whereby the powder outlet is connected to a powder outlet valve. In addition, a powder conduit is provided that is connected, on the inlet side, to the powder outlet valve and includes, on the inlet side, an inlet for transport air. The powder conduit can be connected, on the outlet side, to a powder applicator. Moreover, a control is provided that is designed and operable appropriately such that it controls the amount of powder to be conveyed by repeatedly opening and closing the powder outlet valve.
Abstract:
The invention relates to a dense phase powder pump and a method for operating a dense phase powder pump in a powder-conveying mode. In order, in a simple manner, to prevent or at least reduce powder accumulations and clogging with powder, in particular on the powder inlet side of the powder conveying chamber of the dense phase powder pump, and thus in the region of the powder inlet valves, according to the invention, during a predefined or specified time period in at least one output phase and preferably at the end time of the output phase of a powder cycle, at least one of the following conditions exists: i) the powder inlet valve of the dense phase powder pump is open; ii) the powder outlet valve of the dense phase powder pump is closed; and/or iii) the application of an overpressure to the powder conveying chamber of the dense phase powder pump is interrupted.
Abstract:
A multi-port metering pump assembly may include a manifold coupled to a metering pump. The manifold may define a central passage in fluid communication with a plurality of intermediate passages defined in the manifold. The manifold may further include a plurality of outer passages of the manifold. Each intermediate passage may provide fluid communication between the central passage and a corresponding outer passage. A plurality of valves may be coupled to the manifold. Each valve of the plurality of valves may be located between an intermediate passage and a corresponding outer passage, and be configured to enable or prevent passage of fluid between a corresponding intermediate passage of the plurality of intermediate passages and a corresponding outer passage. The multi-port metering pump assembly may also include an electronic controller coupled to the plurality of valves, the electronic controller having an associated electronic interface and being programmable to selectively and independently open and close the valves of the plurality of valves.
Abstract:
A nozzle assembly for a material application device includes an expansion chamber for slowing down the velocity of powder fed to the nozzle from a dense phase pump. The nozzle assembly includes a nozzle insert that forms the expansion chamber and provides air assist function. The nozzle includes an integral deflector, and further includes a passageway for a charging electrode so that the electrical path is routed away from the powder path, while permitting the electrode tip to be centered in the powder spray pattern from the nozzle. The nozzle also includes air wash for the electrode. The nozzle outlet orifice has a cross-sectional area that is equal to or greater than the inlet cross-sectional area so that a slow moving dense phase powder cloud is produced by the nozzle.
Abstract:
A pump for particulate material includes a pump chamber wherein material flows into the pump chamber under negative pressure and flows out of the pump chamber under positive pressure. A plurality of pinch valves are provided to control flow of material into and out of the pump chamber. The pinch valves are operated independent of each other and of the pump cycle rate. A modular design of the pump is provided. A pump control feature is provided for air flow rate control during positive and negative pressure conditions.
Abstract:
A powder feed apparatus for a powder spraycoating equipment includes a dense phase powder pump fitted with at least two feed chambers, alternatingly discharging coating powder. Each feed chamber includes a powder intake valve to aspirate coating powder during a suction stage and one powder outlet valve to discharge coating powder during a discharge stage. Each feed chamber further includes control valves to operate the dense phase powder pump and a control unit controlling the dense phase powder pump by the control valves. A dependence mode of the total open time (ttotal) of the powder intake valves defines the dependence of the total open time (ttotal) on an adjustable nominal value (mp) adjusted by a powder adjusting element and relating to the rate of powder to be conveyed by the dense phase powder pump, and defining a response delay time (tdelay) and an apparatus constant (C).