RU1787613C - Medical electrode manufacturing method - Google Patents

Abstract

Usage: in the field of medical technology in the manufacture of electrodes for percutaneous electrical stimulation. SUBSTANCE: a spiral of 20 mm diameter X20H80 wire is wound onto a cylindrical mandrel with a diameter of 20 mm, elongated in increments of 4 mm. The winding pitch is equal to the diameter of the spiral. The winding width is determined by the dimensions of the electrode and is equal to 120 mm. The winding is done in two layers. Then the preform is removed from the mandrel, a folded spiral of the base material is introduced into its cavity, and the whole preform is pressed in a rectangular mold into a plate 120 mm long, 30 mm wide and 0.8-0.9 mm thick. 2 ill.

Description

The invention relates to medical equipment, namely electrodes for percutaneous electrical stimulation. A known method of manufacturing medical electrodes of elastic porous metal MR, which consists in cold pressing with a force of 10-20 mn / m of workpiece from randomly laid continuous spirals with a diameter of 2.5 mm from a wire of 0.15 mm uniformly distributed over the area of the mold punch, the dimensions of which correspond the size of the manufactured electrode.

This method of manufacturing electrodes does not allow to obtain high uniformity of the material with a small thickness of the electrode due to the chaotic stacking of wire spirals in the billet for pressing and requires special equipment (die, punches). In addition, electrodes made in this way require the soldering of current leads to them. All this does not allow to obtain a uniform floor with the help of such electrodes, creates a risk of mechanical damage to the skin and oxidation in the soldering zone, and requires the development of special equipment for each electrode size.

The aim of the invention is to develop a method of manufacturing an electrode with high uniformity of distribution of the wire with a small thickness, the safety of its use through the use of simpler equipment.

The goal is achieved by the fact that in the known method for manufacturing medical electrodes from MR material, an arrangement is proposed for arranging an extended spiral with uniform winding on a cylindrical mandrel with a step equal to the diameter of the spiral (i.e., coil to coil). The subsequent winding layer is rotated relative to the first layer by an angle of 30 °. A stranded preform for pressing extrudes a stranded wire from a wire of the base material that protrudes significantly

with

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With

the billet and the billet are extruded by an open method (i.e., without a die).

The orderly laying allows to obtain a high uniformity of distribution of the electrode material over its volume, the rotation of the subsequent layer relative to the previous one by an angle of 30 ° ensures effective cohesion of the spirals during pressing and, as a result, high bending strength of the finished electrode. The use of a cylindrical mandrel makes it possible to automate the process of forming a workpiece and to obtain a hollow one with equal edges. This allows you to get rid of the matrix during pressing (i.e., use open pressing) and to press into the cavity a long stranded wire of electrode material that protrudes significantly from the finished electrode. This wire can be used as a conductor.

In FIG. 1 shows a method of laying a spiral in a workpiece, where 1 is a spiral of wire, 2 is a cylindrical mandrel; in FIG. 2 - located conductive stranded wire inside the workpiece, where 3 - stranded conductive wire, 4 - billet for pressing.

A study of the electrodes obtained by the described method showed their high operational properties — good bending strength and a uniform electric field on the electrode surface.

Example. A coil of X20H80 wire with a diameter of 0.1 mm, elongated in increments of 1 mm, is wound onto a cylindrical mandrel with a diameter of 20 mm. Mass of wire 4 gr.

The winding pitch is equal to the diameter of the spiral. The winding width is determined by the dimensions of the electrode and is equal to 120 mm. The winding is done in two layers. Then the preform is removed from the mandrel, a stranded wire of the same material is inserted into its cavity, and the whole preform is pressed in a rectangular mold into a plate 120 mm long, 30 mm wide and 0.8-0.9 mm thick.

Compared with the prototype, the alleged invention allows to obtain a high uniformity of distribution of the electrode material over its volume, as well as good bending strength and a uniform electric field on the surface of the electrode.

Claims (2)

1. A method of manufacturing medical electrodes from a metal wire spiral, including the manufacture of a hollow workpiece from a wire spiral by winding a stretched spiral onto a mandrel with a step equal to the outer diameter of the spiral. Removing the mandrel and subsequent cold pressing of the hollow workpiece in a mold, characterized the fact that, in order to improve the quality of the product by obtaining its electrophysical properties, when winding the next layer of the spiral, it is oriented relative to the previous layer by rotation through an angle of 30 ° 2. The method according to claim 1, characterized in that before pressing into the cavity of the preform, a loop of a wire spiral is introduced, the length of which is chosen to be at least two lengths of the preform. Figure 1 Thebes. 2