Patent UA-72061-C2 (UA)
Title: Method and device for washing of supports of printed circuit boards prior to vacuum deposition
Inventor: BULGAKOV OLEG ANATOLIIOVYCH
IPC: B08B3/02
Filed: 2004-07-28
Abstract: The invention discloses a method for washing of supports of printed circuit boards prior to vacuum deposition and the device, which consists of corresponding units and connections between them. The method consists in that the supports are placed into the cassettes fastened on the suspension brackets, the washing is carried out in several modules of the bath for washing, the suspensions brackets with cassettes containing supports are reloaded from one module for washing into another manually, the suspensions brackets with cassettes are treated in the washing module by counterflow of cleaning fluid, for that the suspensions brackets are immerged into an inclined, open from above pipe connected with the source of cleaning fluid and with an inclination in opposite side from it, the beams of parallel jets of cleaning fluid are supplied into the module for intensive flow washing, said beams are formed with the help of corresponding elements of separating collectors arranged in staggered rows, said elements of separating collectors, if required, are turned for an angle up to minus 45 degrees with respect to their horizontal axis thus creating the area for jet washing, the suspension brackets with cassettes containing the supports perform reciprocal motion in the vertical plane in the area of jet washing, the part of jets of cleaning fluid, which are not involved in the washing of supports, are caught and localized with the help of the area of jet washing of pipes, said area being open on height and width, the pipes are connected with the source of cleaning fluid and with an inclination toward its side, in the module for intensive jet washing the supports with cassettes containing supports is turned for 180 degrees and other side of supports of printed circuit boards is treated in the area of jet washing, after the module for intensive jet washing of the suspension bracket with cassettes are treated in the vibrating module, for that the suspension brackets with cassettes containing supports, with the help of a crank shaft with gap-forming devices are periodically immersed into the cleaning fluid with different linear and angular jump accelerations with different signs and values, the resistance of cleaning fluid is measured in the vibrating module, the measured value is compared with set value, the washing of supports is completed when the measured value of resistance of cleaning fluid in the vibrating module is lower than the set value, besides in the vibrating module with the help of heaters the temperature of cleaning fluid is maintained within the range from 50 DEGREE C to 120 DEGREE C with an error not higher than 5 DEGREE C, and the elements of separating collectors, which form the beams of parallel jets of cleaning fluid in the module of intensive may be turned in the horizontal plane, if required, for an angle up to 45 degrees. The invention allows reducing time consumption for washing of suspension brackets of printed circuit boards, improving the quality of their washing and reducing the percent of rejection of output products and consumption of cleaning fluid.