JPS5819756B2 - Electrodeposition processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrodeposition processing method for forming a thick and uniform electrodeposition layer on a workpiece such as a base material or an electroforming mold.

In narrow recesses and corners of the workpiece, the potential gradient is low and electrical shadowing occurs, making it difficult to form an electrodeposited layer. It is not possible to form a uniformly thick electrodeposited layer over the entire workpiece simply by applying electricity.

For this reason, in the present invention, the facing gap is first narrowed sufficiently, and then the electrode or the workpiece is subjected to vibration or reciprocating motion so that the electrodeposition liquid can well enter the narrow gap.

In this way, as the machining of a narrow recess or a corner of the workpiece progresses, the electrode or the workpiece is separated, the gap is widened, and the electrodeposited layer is laminated over the entire surface. do.

The present invention will be described below with reference to the drawings. Reference numeral 1 denotes a workpiece such as an electroforming mold, in which a processed surface 1a on which an electrodeposited layer is formed is V-shaped, and a bottom surface 1b forms a narrow recess 1b.

Reference numeral 2 is an electrode, and a thin electrode is used that can fit into the plate, rod, or linear narrow recess 1b depending on the processing shape, and the unnecessary parts on the side surfaces are insulated with coating 2aL with an insulating coating material. .

3 is a control device that supports the electrode 2 and gives vertical vibration or reciprocating motion; 4 is a servo control device for opposing the gap between the electrode 2 and the workpiece 1; the gap is initially narrowed under control by the NC control device 5; Perform control to gradually expand.

Reference numeral 6 designates a processing power supply that supplies DC pulses or DC current or the like between the electrode 2 and the workpiece 1, and 7 designates a nozzle that supplies an electrodeposition liquid, both of which are controlled by an NC control device.

In electrodeposition processing, the electrode 2 is first opposed to the narrow recess 1b of the workpiece 1.

The opposing gap is maintained at a minute gap by a servo device 4 under NC control, electrodeposition liquid is supplied to the opposing gap from a nozzle 7, and processing current is applied from a power source 6.

An electrodeposited layer is formed on the cathode-side workpiece 1, and a large amount of new electrodeposited liquid can be supplied to the gap, which is kept small during processing, by the vertical vibration or reciprocating movement of the electrode 2, and by the electrode movement. Since the pumping action works to remove and clean generated gas decomposition products, etc., electricity can be stably passed at a high current density even in narrow gaps, and high-speed electrodeposition can be performed.

The electrodeposition gap during processing is maintained at a constant minute gap by the servo device 4 in response to a signal given by the NC control device 5, and the high-speed electrodeposition processing described above is carried out.

By proceeding with stable electrodeposition processing in this minute gap, electrodeposition is efficiently carried out in the electrically shaded portions of the narrow recesses 1b, and the four portions 1b can be easily filled with the deposited metal in a short time.

In response to this metal deposition, the servo device 4 uses, for example, the gap voltage as a signal to retract the electrode 2 and control the minute gap to remain constant at all times. A signal is output to the servo device 4 to widen the gap at a certain time.

Therefore, in response to this command, the servo device 4 controls the electrode 2 to move back further to widen the electrodeposition gap more than before, thereby widening the area of the applied electric field.

At this time, the aforementioned narrow concave portion 1b is filled with the deposited metal and the electrically shaded portion is eliminated or reduced, so that the electrodeposition process is performed over a wide portion of the electrodeposition surface 1a.

When the electrodeposition process further progresses and the ■-shaped attachment surface of the workpiece 1 becomes flat, the servo device 4 is controlled in accordance with the command from the NC control device 5 to further widen the electrodeposition gap, and the electrode 2 moves back greatly to widen the gap and widen the area of the applied electric field, apply an electric field to the entire electrodeposition surface 1a of the workpiece, perform electrodeposition, and form a predetermined thick electrodeposited layer for finishing.

Note that the signal for widening the electrodeposition gap from the NC control device 5 may be controlled stepwise or continuously each time a predetermined electrodeposition step is completed, and the signal for widening the electrodeposition gap may be controlled in either direction. For example, by controlling the reference voltage with which the detection signal from the gap is compared and increasing it, the gap can be widened to a predetermined value.

In addition, the NC control device that generates and controls control signals can use a microcomputer, and can perform corresponding control while detecting the state of the processing gap, controlling the current density, electrodeposition liquid flow rate, flow rate control, liquid temperature, PH control, metal ion control, vibration, reciprocating motion, and the like can be controlled in a rainy manner.

It is also effective to mix gas into the electrodeposition solution, and it is also possible to control this, as well as control the pulse width, pause, frequency, peak value, etc. during pulsed energization. Conditions can always be controlled to the best condition.

As explained above, in the present invention, electrodeposition is performed by applying vibration or reciprocating motion to the electrode or the workpiece with the facing gap narrowed first, so that electrical deposits can be applied to narrow recesses or corners of the workpiece. Metal can be easily deposited and filled in areas where shadows are likely to occur, and when the shadow areas are filled and flattened as the electrodeposition process progresses, or as they become flat, the electrodeposition gap is expanded and acts. By expanding the electric field area and controlling the electrodeposition to affect the entire machined surface to form a uniform electrodeposition layer over the entire surface, it is possible to easily form a thick metal layer with no uniformity over the entire surface, making it easy to form the desired electroformed layer. It has the effect of being able to process in a short time.

[Brief explanation of the drawing]

The drawings are detailed illustrations of the invention. 1... Workpiece, 1a... Machining surface, 1
b... Narrow recess, 2... Electrode, 3...
...Vibration or reciprocating motion device, 4...
・Servo device, 5...NC control device, 6...
...Power supply, 7...Liquid supply nozzle.

Claims (1)

[Claims] 1. While vibrating or reciprocating the opposed electrodes or the workpiece, first narrow the facing gap, supply an electrodeposition liquid, and conduct the electrodeposition by applying electricity to narrow the workpiece. An electrodeposition processing method characterized by widening the facing gap as the processing of a concave portion or a corner portion progresses.