Abstract: A module and process for removal of dissolved metal from a solution comprising converting said solution to an electroless plating solution and passing said electroless plating solution through a fixed bed of foam where the walls of the foam have been catalyzed with an electroless metal deposition catalyst.

Abstract: Disclosed is a method and apparatus for positioning a pair of opposed brush assemblies in a gap defined by end baffles between process chambers. The brushes have a plurality of offset bristle clusters secured to a header, and the header is preferably angled so that the brushes will have a wiping action as a workpiece such as the printed circuit board passes between the bristles. A pair of brushes are employed with the opposed ends in overlapping relationship providing a wiping-type gate, and which permits the entrained fluid to drip down the bristle hairs and into the chamber from which the workpiece such as a printed circuit board is being removed. Optionally the brush bristles can be angled upwardly to incite a gravity assist for the entrained fluid dripping down toward the header of the brush and into the process tank.

Abstract: Disclosed is a plating module and method in a cell which has linearly spaced vertical anodes, and intermediately positioned spargers which can be angularly adjusted with their nozzles impinging directly or at an acute angle on the printed circuit boards positioned at a mid-point in each cell. The printed circuit boards are suspended in clamped relationship to a cathode bar. The cathode bar, in turn, in each unit is coupled to a reciprocating power drive so that the same will move back and forth an optimum distance of at least the spacing between an anode and a sparger, or more particularly, half the spacing between two spargers. The method of the invention contemplates positioning boards to be plated, whether with copper or tin, interiorly of the unit in which the boards are reciprocated in agitation relationship with a plating solution into which an anodes are positioned. The boards are then permitted to reciprocate for a given period of time with a preselected current density.

Abstract: Disclosed is the continuous processing of flat workpieces such as printed circuit boards which are suspended by a hanger conveyorized for continuous horizontal transport. More specifically, the conveyorizing passes the workpieces through a plurality of chambers having slotted-end members, one such chamber spraying to remove the photoresist, and another such chamber spraying etching solution to remove the copper cladding. Each station has a slotted cover, and the conveyor suspends a plurality of workpiece holders, each of the holders being joined by chain links of an inert material which overlie the slot in the covers for the chambers. The photoresist chamber is provided with a continuous filter for cntinuously removing and filtering the sludge, thereby reducing the tendency of the removal solution to dilute and become ineffective. All of the chambers are modularized, and the system is compatible with continuous processing for the plating of the printed circuit boards.

Abstract: The present invention deals with the continuous metal exchange for workpieces such as a printed circuit board which can take place in a plating tank. The workpieces are conveyorized for continuous horizontal transport into and out of a plating tank. Opposite ends of the tank are provided with slots to receive and discharge the workpieces which are sealed, in the instance illustrated, by opposed rollers or an open slot of small area to prevent leakage in excess of the pump capacity. The workpieces are suspended at their upper portion by a non-conductive hanger, the lower portion of which is rendered conductive. When the workpiece enters the plating tank the conductive portion of the hanger suspending the workpiece from the conveyor, makes contact to energize bus bars thereby converting the workpiece to a cathode (or anode if metal is to be removed). A plating solution is inside of the tank and provided with anodes or cathodes energized for metal exchange.

Abstract: Disclosed is an apparatus which utilizes pipes of different lengths oriented vertically within the fluid of a reservoir which are constantly pressured with a gas source, normally air. Since the pipes are of different length, but the pressure is the same, a different back pressure will occur in the longer pipe as compared to the shorter pipe due to the differing head of fluid which must be displaced by the gas to slowly bubble out of the lower end of the pipes. This pressure differential is then read and the calculations applied, either from a table or constantly monitored through a computer, to measure the pressure differential and calculate the same in terms of specific gravity. Once the specific gravity is known, the back pressure on either the short pipe or the long pipe can be impairedly calibrated, or calculated by an equation having the specific gravity now known, and then determining from that the back pressure which will vary with the height of the fluid in the reservoir.

Abstract: Disclosed is a shielded plating cell which will permit continuous transfer of a printed circuit board by a single conveyor, whether chain-type, endless belt, or other unit is employed. The plating head and sparger assembly include a reverse flow chamber in which an anode is positioned thereby reversing the flow of the pressure fluid and creating a venturi effect in an area beneath a pair of shields which flexibly engage the printed circuit board and shield the upper portion as well as environment from the escape of spray. To assist in this shielding, an adjustable choke is provided so that the operator can manually balance the unit by shifting the choke to eliminate any pumping action which occurs in the delta formed at the ends of the printed circuit boards where the shields do not abruptly come together. Additionally, squeegee gates are provided at both ends of the cell to inhibit the migration of plating fluid outside the cell into related processing areas.

Abstract: Disclosed is a sparger in which there are a plurality of nozzles extending from a vertical sparger pipe, and alternating the vertical sparger pipes or sparger tubes have the nozzles at mid-stations between the adjacent sparger nozzles; with the entire sparger being directed to discharge the fluid to impinge upon the workpiece such as a printed circuit board at an acute angle preferably less than 90.degree.. The resulting pattern on the workpiece is a plurality of footprints, all overlapping a minimum amount on the target area. A further aspect of the invention is directed to having the spargers on one side of the workpiece direct fluid in a downstream direction, whereas the spargers on the opposite side of the workpiece direct the fluid in an upstream direction or contra to the movement of the workpiece such as a printed circuit board.

Abstract: Disclosed is the continuous processing of flat workpieces such as printed circuit boards which are suspended by a hanger conveyorized for continuous horizontal transport. More specifically, the conveyorizing passes the workpieces through a plurality of chambers having slotted-end members, one such chamber spraying to remove the photoresist, and another such chamber spraying etching solution to remove the copper cladding. Each station has a slotted cover, and the conveyor suspends a plurality of workpiece holders, each of the holders being joined by chain links of an inert material which overlie the slot in the covers for the chambers. The photoresist chamber is provided with a continuous filter for continuously removing and filtering the sludge, thereby reducing the tendency of the removal solution to dilute and become ineffective. All of the chambers are modularized, and the system is compatible with continuous processing for the plating of the printed circuit boards.

Abstract: A connector plated contact point having a curvilinear area terminating in a feather edge. Optionally the contact has a conductive underbody having a feather edge. Both feather edged metals have a raised central portion. The contact is formed on a contact plater having a pair of opposed belts for grasping and driving contact point through a pair of opposed jaws to be plated by contact on an anode roller, the same describing a helical trace on the roller.

Abstract: Disclosed is a method and apparatus for processing printed circuit boards which do not have a plating buss or plating bar by means of continuously passing the printed circuit boards through a plating cell in which a cathode brush is employed to contact the leads above the tabs while the brush is shielded both above and below in a chamber defined by a pair of shields. Desirably the chamber is pressurized with a gas, normally air, to preclude the migration of solutions such as electroplating solution from the plating cell onto the brush which would become plated itself and lose its effectiveness if contacted by the electrolyte. The plating cell utilizes a sparger and reverse flow chamber and an anode, the anode being positioned essentially in the reverse flow chamber to accomplish the plating. The anode is electrically energized and the cathode is independently energized to provide the current necessary for the plating.

Abstract: The present invention is directed to employing a rectilinear chamber for desmearing in which the two transitional ends are frustopyramidal in configuration. Each frustopyramidal diffusion chamber has a controlled exhaust valve which is piped to the vacuum pump. Gas can be introduced to the diffusion chamber at a point adjacent the exhaust valve and centrally therefrom. Ideally there are an odd number of electrode pairs spaced vertically which generate a primary field, and the further spaced apart pairs generating a secondary field therebetween. Because the chamber is rectilinear, it can be proportioned to accommodate vertically spaced MPWB's in the secondary chamber portions.

Abstract: A tab plater for purposes of stripping tin lead from contact tabs, and replating the same for further preservation and improved electrical contact with metal such as nickel and gold is shown having a plurality of processing stations. The printed circuit boards are passed through various stations where plating or stripping is undertaken and masked by means of the transport system comprising opposed resilient belts and means for sealingly engaging the printed circuit board at a line of demarcation. The printed circuit boards are passed over positioning stations to transfer from one location to another to insure precise positioning of the line of demarcation.