SU1294587A1 - Method of jet hydroabrasive working of workpieces - Google Patents

Abstract

The invention relates to the field of sandblasting metals, and in particular to methods of hydroabrasive processing of flat surfaces, i have; n; their holes, mainly printed circuit boards. The aim of the invention is to increase the processing efficiency of flat, perforated pieces by providing a force action with an oscillating plate on the reflection from the surface of the jet of the working agent. For this purpose, the working agent jets 5 are directed to the workpiece 1 using jet nozzles 2. Between the nozzles 2 and the treated surface 3 parallel to the latter set plate 6, which reported oscillatory motion with a frequency of 1-2 Hz in the direction normal to the treated surface. The amplitude of the oscillations A of the plate 6 is set from the conditions A, 0.25d 1 h, sH, D, eP «B.O, 25a / b, where h mih are, respectively. the largest and smallest distances between the plate and the part, m; d is the diameter of the outlet nozzles, m; H is the distance between the nozzles and the part, m; L is the distance between the axes of adjacent nozzles, m. 1 nl. cl

Description

The invention relates to an inkjet for the damming of flat surfaces of parts with holes, mainly printed circuit boards.

The purpose of the invention is to increase the efficiency of machining the flat surfaces of parts with holes.

This goal is achieved by the fact that the surface being treated is simultaneously affected by jets of a hydroabrasive suspension and an oscillating plate, which forcefully compresses the flow of the working agent reflected from the part.

The drawing shows the implementation of the proposed method of jet waterjet processing of the part.

The method consists in that the detal 1 is moved relative to the jet nozzles 2, and is directed onto the surface 3 with holes A of the jet 5 of the hydroabrasive suspension, which is used for processing. Between the nozzles 2 and the surface 3 to be machined, a plate 6 is installed parallel to it, which by known means sets in oscillatory motion with a constant frequency and amplitude in the direction of the axes of the holes 4.

In the process of oscillating movement, the plate 6 periodically acts on the flow of the working agent reflected from the surface 3 of the part 1, making it compress and force-pressing through the openings 4 of the surface to be treated. This provides an abrasive treatment of the holes 4 and the surface 3 of the part 1.

The processing efficiency is determined by the amplitude of the plate oscillation equal to A h | -h, which is set based on the following conditions: at maximum removal

h plate 6 from processed

the surface of the part 1 should be provided with a free filling of the gap between the treated surface 3 and the plate 6 of the hydroabrasive suspension, which is equal in volume to the total flow of the suspension through the nozzles 2, and

with the minimum approaching h plasmin

Tina - a full forceful repulsion of the reflected flow of the suspension from the gap should be ensured.

10, The oscillation frequency of the plate is set in the range of 1-2 based on the requirements for quality processing.

Example. Hydro-abrasive processing of samples of parts (printed circuit boards) in the form of plates with dimensions of 40,200 mm, 2 mm thick, with openings with a diameter of 1 mm, which are located in the nodes of a square grid with 10 mm pitch, was carried out. The material of the plates - foil dielectric brand SF-2. The jet treatment was carried out using four nozzles with a hole diameter of 4 mm, which were installed at a distance L 50 mm to the surface of 3 parts,

C, the flow rate of the hydro-abrasive slurry was set at 20 0.39-10. The amplitude And h - oscillations of the plate 6 was set

15

min

equal to 10 mm at the maximum distance of the plate from the part h

Mane

Rav25

thirty

- 40 n 10 .mm, and,, respectively, equal to the size of the grains of the grains of the abrasive material, namely b „„ „D 0.05 mm. The processing time was monitored until a given treatment quality was achieved, i.e. no burrs and fibers of glass fiber on the surface 3 and in the holes 4 parts, depending on the oscillation frequency of the plate, which was 1.9-9 minutes. A mi-, 35 minimum processing time, equal to 1.9 min when the specified quality was achieved, was obtained in the range of plate oscillation frequencies of 1-2 Hz. With an increase in the frequency of more than 2 Hz, the performance does not change; however, I increases the energy consumption when implementing the proposed method.

The proposed method achieves an increase in the efficiency of the blasting process for flat parts with holes due to a force effect on the reflected flow of a hydroabrasive suspension oscillating with a plate.

Claims (1)

Invention Formula The method of jet waterjet processing of parts, in which a part by means of nozzles is supplied with a hydroabrasive suspension, characterized in that, in order to increase the efficiency of part processing 129458 with holes, take a plate with holes, place it between the nozzles and the workpiece parallel to the last one and inform the plate of oscillatory motion along the axes of the holes to be machined.  1-2 Hz and A h, 0,25 d .. h P; D,., ". - - “-. where is the frequency of oscillating movement of platinum Op V.Danko 430/15 Compiled by O. Zhukov Tehred L. Serdyukova Circulation 716 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5 Corr Podpi Manufacturing one-polygraphic enterprise, Uzhgorod, st. Project, 4 A d N } "(" AKC amplitude of the oscillatory motion of the plate, m / diameter of the nozzle outlet, m; the distance between the nozzles and the part, m; - size of abrasive grain, m, - the smallest distance between the plate and the part, .m1 - the largest distance between the plate to the part , m; L is the distance between the axes of the neighboring | nozzles Proofreader M. Demchik Subscription