JPS5914111Y2 - Electrolytic buffing compound polishing device - Google Patents

Description

[Detailed description of the invention] This invention combines the electrolytic elution action of electrolysis with the abrasion action of an abrasive material, thereby making it possible to polish the inner surface of a cylindrical object to be polished to a high-quality surface at low cost. This invention relates to an electrolytic puff composite polishing device.

Conventional electrolytic polishing is simple, but it requires an expensive strong acidic electrolyte and also cannot handle a large current density.
Processability is low, and cleaning before and after electrolytic polishing and several stages of mechanical pre-finishing polishing are required, making it difficult to reduce costs.

In particular, the smoothness of the surface against unevenness depends on the chemical removal of the passive film by a strong acid electrolyte, and although there is a preferential selection effect on convexities, the removal effect on so-called "undulations" and "scratches" is extremely low. , therefore it is difficult to obtain a high quality surface.

Therefore, as a method to solve this problem, an electrolytic puff composite polishing method can be considered, which combines the elution action of electrolysis with the abrasion action of a puff.

In this method, cross-shaped electrode surfaces and abrasive material are arranged alternately on a disc-shaped tool electrode, and a neutral salt aqueous solution is spouted from the center of the tool electrode, and the tool electrode is rotated, thereby making compound polishing possible. It is related.

According to this, when the object to be polished is a flat plate, a flat plate tool electrode is used, and when the object is the inner surface of a large diameter cylinder (diameter 1000 mm or more), a tool electrode with a spherical surface that is approximately the same as the inner diameter is used. Effective polishing is performed in each case.

However, in the case of a cylindrical object with a small diameter, if a rotating tool electrode is used, the area to be polished will be extremely small, resulting in line contact, which will reduce the polishing efficiency, and especially in the case of a mirror finish. The disadvantage is that it tends to result in a uniform finish.

Therefore, the present invention aims to eliminate these drawbacks and provide an electrolytic puff composite polishing device that can effectively and uniformly mirror-finish the inner surface of a small-diameter cylindrical object.

An embodiment of the present invention will be described below with reference to the drawings.

1 is a cylindrical object to be polished, which is connected to an anode.

Reference numeral 2 denotes a support shaft inserted into the object to be polished 1 coaxially with the object to be polished 1, and is rotated in the direction of arrow A by a drive device (not shown).

Reference numeral 3 denotes a guide column fixed to the support shaft 2 by screws 4, and 5 is a slide column inserted into the guide column 3 so as to be freely pulled out. It is biased toward the inner surface of the body 1.

Reference numeral 6 denotes a tool electrode holder having a U-shaped cross section, which is fixed with a screw 7 to the tip of the slide column 5, and is connected to the cathode.

A tool electrode 8 is fixed to the open surface of the holder 6 with screws 9, and an electrode surface 8a of the tool electrode 8 is formed in an arc shape along the inner surface of the object 1 to be polished.

10 is about 4 in the axial direction of the object to be polished 1 on the electrode surface 8a.
The insulating tapes are pasted at appropriate intervals α along the five intersecting directions.

Therefore, the insulating tape 10 and the working electrodes A that act on electrolysis are alternately formed into three stripes.

On the surface of the tape 10, a large number of protrusions 11 each having a large-diameter spherical or fishhook tip are protruded.

Reference numeral 12 denotes two electrolyte jetting slits formed in the tool electrode 8 and the insulating tape 10 along the axial direction of the object to be polished 1, and are formed over almost the entire width of the tool electrode 8.

Reference numeral 13 denotes an abrasive material that covers in an L-shape from the electrode surface 8a to the front side surface of the holder 6 in the rotational direction A, and is made of a non-woven fabric having water permeability, insulation properties, and elasticity. It engages with the protrusion 11 of the tape 10 to prevent it from coming off the tape 10.

14 holds one end of the abrasive material 13 via a holding plate 15 with a holder 6.
16 is a connecting fitting that is screwed into a threaded hole formed in the holder 6, and 17 is an electrolyte supply hose connected to the connecting fitting 16.

The outer peripheral surface of the holder 6 is coated with an insulating agent 18 for preventing leakage of electrolytic current.

In this configuration, the power is turned on, the support shaft 2 is rotated in the direction of arrow A, and the electrolyte is supplied into the holder 6 via the hose 17.

Then, the electrolytic solution in the holder 6 is sufficiently supplied into the abrasive material 13 through the slit 12, and a layer of electrolytic solution is formed between the tool electrode 8 and the object to be polished 1, so that the elution effect due to electrolysis and , and the abrasive action by the abrasive material 13 are performed in combination, and the inner surface of the object to be polished 1 is mirror-finished.

Next, a specific example will be described.

The object to be polished 1 has an inner diameter of 450 mmφ and a length of 1.5 m.
The material is SUS 304, the surface roughness of the base is 8-10.
μRmax.

The electrode surface 8a is 100 x 150 mm, the working electrode A that acts on electrolysis has an inclination angle θ = 45°, a width α = 10 mm,
The pitch is P-30mm.

The tool electrode 8 was pressed with a force of 30 kg f (pressing pressure of 0.2 kg
/cmQ against the inner surface of the object to be polished 1, 90 to 100
Rotate in the direction of arrow A at rpm.

When the object to be polished 1 is connected to the anode and the tool electrode 8 is connected to the cathode, a direct current of 8 cm is applied, and a 20% aqueous solution of sodium nitrate is supplied as an electrolyte at a rate of 5 to 101/min, 60 to 8
An electrolytic current of 0 A flows, allowing electrolytic puff composite polishing.

When this rotational polishing is carried out for 3 to 5 minutes, the inner surface of the object to be polished 1 becomes 0.2 to 0.1 μRmax or less, and when the electrode surface 8a is sequentially moved horizontally by the width (150 mm), the object to be polished can be polished in 40 to 60 minutes. The entire inner surface of body 1 has been finished.

Furthermore, when similar composite polishing is performed by mixing abrasive grains into the electrolyte at a rate of 10-15 g/l, the result is 0.1 μmRmax.
Finished with the mirror finish shown below.

As described above, according to the electrolytic puff composite polishing device of the present invention, electrolytic puff composite polishing is performed using the tool electrode and abrasive material provided on the spindle by rotating the spindle that is concentric with the object to be polished. Therefore, even the inner surface of a small-diameter cylindrical object can be effectively and uniformly mirror-finished.

Further, one end of the abrasive material is fixed to the front side surface of the tool electrode in the direction of rotation, and the abrasive material is fixed to the electrode surface by a large number of protrusions.

Therefore, the abrasive material does not peel off during polishing.

During maintenance, the abrasive material can be removed from the protrusion by simply grasping the other end of the abrasive material and lifting it up, allowing the abrasive material to be peeled off from the electrode surface. It is extremely easy to replace the abrasive, and the abrasive can be removed simply by removing one end of the abrasive from the tool electrode, making it easy to replace the abrasive.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Figure 1 is a longitudinal cross-sectional view (the cross-sectional line is along the line ■-■ in Figure 2), Figure 2 is a plan view of the tool electrode, and Figure 3 is the main part. FIG. 1...Object to be polished, 6...Holder, 8.
...Tool electrode, 8a... Electrode surface, 10.
...Insulating tape (insulator), 12 ... Slit, 13 ... Abrasive material, 14 ... Screw, I ... Working electrode.

Claims (1)

[Scope of utility model registration request] A spindle is provided that is inserted concentrically into the cylindrical object to be polished and is rotated in one direction by a drive device, and a polishing tool electrode is disposed on the spindle so as to be movable along the radial direction of the spindle. A spring is provided to bias the tool electrode toward the inner surface of the object to be polished, and the electrodes are placed at appropriate intervals on the electrode surface of the tool electrode along a direction diagonally intersecting the axial direction of the object to be polished. An insulator is attached, and an appropriate number of slits for spouting the electrolyte are formed in the tool electrode and the insulator along the axial direction of the object to be polished.
A large number of protrusions are provided on the surface of the insulator, and the protrusions are disposed on the insulator to cover the electrode surface, engage with each protrusion, and have one end fixed to the front side surface of the tool electrode in the direction of rotation. An electrolytic puff composite polishing device characterized by being provided with an abrasive material.