Abstract:
A spray coating system has a wash enclosure with an enclosed wash space. A plurality of liquid tanks disperse liquids within the wash space via emitters. A spray enclosure has at least one spray port coupled to an enclosed spray space. A part hanger dimensioned to carry parts, is rotatable about a vertical axis while in the wash space and the spray space. A conveyor may be included, for example, for transporting the part hanger between the wash space and the spray space.
Abstract:
Exemplary monitoring methods and monitoring devices are disclosed, e.g., for an electrostatic coating plant which coats components with a coating agent that is electrically charged by means of a high voltage device. An exemplary monitoring method comprises determining a first operating variable of a high voltage device, comparing the first operating variable to a limit value, and initiating a safety measure if the comparison between the first operating variable and the limit value indicates a disturbance in the electrostatic coating plant. The limit value may be flexibly adjusted depending on the operation mode.
Abstract:
An object of the present invention is to provide an improved electrostatic painting device wherein spray coating may be carried out by keeping a spray distance of the electrostatic painting machine within an optimum distance range which provides a good coating efficiency and to prevent the coating worker from extending unconsciously the spray distance out of the optimum distance range. The electrostatic painting device according to the present invention comprises an electrostatic spray gun 2 provided with a high voltage generation part 201 for supplying a high voltage to atomized painting material, detection means 107 for detecting load current I which varies depending on a change of the spray distance L between the electrostatic spray gun 2 and an article 4 to be coated, processing means 107 having a threshold of the load current value corresponding to the maximum distance within the optimum distance range of the spray distance and adapted to output an alarming signal when the detected load current falls below said threshold and an alarming means 108 adapted to receive said alarming signal and provide an alarming indication.
Abstract:
A system and method for detecting and controlling ungrounded parts during the electrostatic coating process in order to improve production flow, provide an overall cost saving by efficient use of the coating material and prevention of accidental fires and false shutdown during production. The system of the present invention comprises a detection system for detecting any ungrounded parts prior to entering a coating environment, such as a painting booth. The detection system in accordance with one embodiment, comprises an array of detectors, specifically, an ultraviolet sensor, a radio-frequency wave sensor, an acoustic sensor and a light sensor, which upon sensing specific characteristics generate representative signal waveforms. These waveforms are than compared with stored waveforms relating to profiles of sparking or corona discharge characteristics. Correlation circuits may correlate data obtained by two or more sensors in order to ensure that the spark or corona discharge is caused by an ungrounded part. In accordance with an alternative embodiment, the detection system comprises a measuring device, such as a sensitive electric field meter, for measuring the electrical potential field between each part to be coated and ground.
Abstract:
Electrostatic spray coating system which accurately determines the actual value of a high voltage present on at least one high voltage electrode as coating material is electrostatically charge. A control or input voltage is measured on the input of a voltage transformer and multiplier circuit and is multiplied by the voltage multiplication factor of the voltage transformer and multiplier circuit, thereby calculating the theoretical or no load value of the voltage on the high voltage electrode. This theoretical value deviates from the actual value of the electrode voltage by the amount of the internal voltage drop across the voltage transformer and multiplier circuit when a current flows in it. The internal voltage drop is determined as a function of the electrode current and is subtracted from the theoretical value in order to generate a signal voltage corresponding to the actual value of the electrode high voltage. The signal voltage is subtracted from a desired value voltage in order to generate a regulating differential voltage for a controller which, in response thereto, regulates the electrode voltage and available power.
Abstract:
In an electrostatic paint spraying installation or the like, a high-tension voltage generator comprises a voltage rectifier-multiplier in a mobile subsystem and a grounding connection in a fixed subsystem. A conductive wire connects an input terminal of the voltage rectifier-multiplier to the grounding connection. When the high-tension voltage generator operates, a high-frequency alternating current residual signal injected into this conductive wire is sensed and measured. The measured value is compared against a reference value that may be variable. The high-tension voltage generator is disabled if the difference between the measured value and the reference value reaches or crosses a predetermined threshold.
Abstract:
An electrostatically aided coating dispensing system in which the high distributed capacitance of a high voltage cable for connecting the high voltage supply to dispensing device is entirely eliminated.
Abstract:
An automatic current overload protection circuit for electrostatic precipitator power supplies of the type utilizing a ferroresonant transformer. A low voltage tertiary winding in association with the transformer provides an output voltage to a sensing circuit for inhibiting current flow into the primary of the transformer when the tertiary voltage falls below a predetermined threshold. Another output voltage developed in association with the high voltage secondary winding of the transformer is also utilized to independently inhibit current flow into the primary of the transformer when the secondary voltage falls below a predetermined threshold. A time delay may be provided to permit operation of the overload protection circuit only in the event of a sustained overload current condition.