Abstract:
The invention relates to a control system of a coating apparatus for a coating medium, such as powder or wet lacquer, comprising at least one coating device, in which a quantity measuring means for determining the amount of coating medium supplied to the coating device, a quantity control means for setting the quantity of the coating medium to be discharged by the coating device, and a digital control device for controlling the operation of the coating device are associated to the or any coating device, wherein the control device, the quantity measuring means and the quantity control means are connected to one another by a bus structure.
Abstract:
A device and method of measuring and controlling the flow rate of a fluid determine analog process variables which are dependent on a volumetric flow of the fluid, and the values thus obtained are converted into digital values, the latter being corrected by an offset value which is dependent on a change of the operating parameters of analog components of the measuring system occurring in the course of operation of the system. To obtain the offset value, an analog process variable is determined during interruptions in operation, when the volumetric flow is zero, and converted into a digital value. This digital value is memorized and used as the offset value when operations are resumed. The digital corrected measured values are supplied to a digital signal processor and the flow rate control is carried out digitally. Preferably, at least one parameter memory is provided for the digital control.
Abstract:
The invention refers to a method of detecting workpieces in an electrostatic coating system, comprising at least one electrostatic coating device, which applies a high voltage to a high voltage electrode, in which the high voltage electrode generates a spray current including electrostatic charges for charging particles of a coating medium to be sprayed, an electrically conductive workpiece to be coated is moved past the coating device, the spray current of the high voltage electrode is determined and it is detected in accordance with the magnitude of the spray current whether the workpiece is in front of the coating device.
Abstract:
The invention refers to a method of controlling a coating device, which discharges a coating medium such as a powder or wet lacquer to a workpiece, in which in accordance with the shape of the workpiece the shape of the cloud of the coating medium discharged is automatically adjusted by changing at least one of the velocity, and the quantity, and the mass flow of the coating medium discharged or shaping air. The invention further refers to a coating installation capable of operating by this method.
Abstract:
The instant invention relates to an apparatus for measuring a powder mass flow in a powder/gas mixture during the conveyance thereof through a feed pipe, the apparatus comprising a velocity measuring device for the powder/gas mixture, a mass measuring device for the powder mass per volume unit, and a calculating device to calculate the powder mass flow based on the velocity measured, the powder mass per volume unit measured, and the dimensions of the feed pipe. The mass measuring device comprises a microwave resonator and means for sensing the resonant frequency and/or the microwave amplitude of the microwave resonator. The microwave resonator is embodied by a coil which is applied on the outside of the feed pipe. The invention likewise proposes a method of measuring the powder mass flow in a feed pipe wherein measuring of the powder mass per volume unit involves establishing a reference resonance of a known powder mass flow, adjusting two measuring frequencies at either side of the reference resonance, measuring the resonator voltage at the adjusted measuring frequencies and forming the difference thereof for a powder mass flow to be measured, and determining the displacement of the resonant frequency based on the voltage differential.
Abstract:
The method according to the invention is suitable for determining a powder quantity in a container and for determining a change in powder quantity, i.e. the powder quantity that is supplied from the container(s). The powder is fluidized in the container, the pressure of the fluidized powder in the container is measured to determine the pressure of the fluidized powder or the change of the pressure between two measurements, wherein the powder quantity in the container, or which was supplied from the container between two measurements is calculated from the pressure or the change in pressure. By the method according to the invention it is possible by a simple pressure measurement to determine the powder quantity which is supplied per time unit from the container and which is sprayed by the coating apparatus, and therefore to determine the supplied powder mass flow.
Abstract:
The present invention provides a method of operating a powder coating system, comprising at least one coating device, a coating compartment and a suction system in the coating compartment. In the method, a workpiece is passed through a coating compartment. The coating powder is discharged by the coating device to the workpiece and excess coating powder is sucked off from the coating compartment, wherein the powder mass flow of the coating powder discharged by the or each coating device is detected and the suction system is controlled in accordance with the powder mass flow. For this purpose the invention provides a powder coating system comprising a measuring means for detecting the powder mass flow of the coating powder discharged by the or any coating device, and an actuator means for setting the suction system in accordance with the powder mass flow.
Abstract:
The invention provides a method for determining the composition of fluidizable solid matter particles, such as powder particles, in which the solid matter particles are fed through a measuring resonator device comprising a high frequency resonator under defined feeding conditions, and a change of the resonant frequency and/or the amplitude of the high frequency resonator is detected in the measuring resonator means, said change being caused by the fed solid matter particles.
Abstract:
The invention relates to a method for producing a profile by extruding powdered metal and/or powdered metal alloys. According to said method, a powder feedstock is heated to an extrusion temperature below the melting temperature of the powder and is expelled under pressure through an opening in a die to form the section. At least one metal or a metal alloy of the powder is a reactive metal that spontaneously forms a natural oxide layer on a free surface and/or the powder contains fibre-type particles that are distributed homogeneously in the powder feedstock and that absorb microwave radiation. The powder feedstock is heated to an extrusion temperature by microwave irradiation. The method permits rapid, uniform heating in all regions of the powder feedstock.
Abstract:
A powder coating assembly comprising a compartment (1) in which workpieces (3) are coated with powder and which includes a discharge belt (15) for conveying excess powder to a recovery unit (5) or a filter unit (4) is characterized in that both a recovery unit (5) and a filter unit (4) are provided, each connected by a separate conduit (16; 18) to an exhaust opening (17; 19) of the compartment (1), and in that a shutoff member (42) is provided in the separate conduits (16; 18) for selectively blocking conveyance of powder to the filter unit (4) or the recovery unit (5).