JPS64479B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method for arranging a cathode for internal anodization on the centerline of a slitted aluminum hollow extrusion.

In this specification, aluminum includes aluminum and aluminum alloys.

2. Description of the Related Art Generally, in industrial robots, vehicles, and other industrial machines, rodless air cylinders are increasingly being used in order to minimize the installation space for air cylinders with long strokes. The cylinder tube of a rodless air cylinder is made of a semi-hollow extruded aluminum material having a slit along its entire length, and the inner surface of the hollow part of the extruded material through which the piston reciprocates. It is necessary to form a hard, i.e., thick, anodic oxide film that has wear resistance. However, since the opening of the hollow extruded material with slits used for cylinders is very narrow at 2 to 3 mm, a sufficiently thick anodic oxide film cannot be formed by normal anodizing treatment. Placing the cathode for internal anodization on the centerline was performed. However, it is very difficult to accurately position the internal cathode, and if the internal cathode is misaligned during the electrolytic treatment, the distance between the inner surface of the slitted hollow extruded material and the cathode will not be equal, and this will cause problems during extrusion. The thickness of the anodic oxide film formed on the inner surface of the mold material becomes uneven, resulting in poor quality.In even worse cases, the internal cathode and the extruded mold material come into contact and sparks occur, resulting in local damage to the extruded mold material. There was a problem that melting occurred and defective products were formed. In particular, the extruded material used in rodless cylinders is very long, e.g. 4 to 5 m, so due to the size constraints of the electrolytic cell (the tank is shallow), the extruded material must be installed horizontally on the electrolytic frame. The internal cathode may bend due to its own weight, or become misaligned due to the movement of the electrolyte, and furthermore, because the inner diameter of the extruded material is small, the cathode and the inside of the extruded material are very likely to come into contact with each other, causing the above-mentioned problems. The problem was that it became even more serious.

OBJECT OF THE INVENTION The object of the present invention is to solve the above-mentioned problems, and to enable the internal cathode to be placed precisely on the center line of the hollow part of the slitted aluminum hollow extrusion.
Therefore, it is possible to form an anodic oxide film of uniform thickness on the inner surface of the extruded material, improving the quality of the extruded material, and also to generate sparks due to contact between the extruded material and the internal cathode during electrolysis. There is no such thing, and there are no defective products.
It is an object of the present invention to provide a method for locating an internal anodizing cathode on the centerline of a slitted aluminum hollow extrusion.

Structure of the Invention In order to achieve the above object, the present invention includes a cathode for internal anodizing, at least a part of which is constituted by a spring, inside an extruded aluminum hollow member having a slit over the entire length at the upper end. Insert one end of the cathode into the center of the insulating cathode hanging member on the outside of one end of the extruded piece, and attach an insulating cathode hanger having a locking part at the upper end at a required point in the middle of the length of the extruded piece. By inserting the holding member through the slit and suspending the middle part of the length of the cathode from the lower end of the cathode holding member, the cathode is placed on the center line of the center of the extruded material, and the other end of the cathode is placed on the spring. By pulling the cathode in the length direction against the elastic force, the cathode retaining member is brought into contact with one end of the extruded material, and in this state, the other end of the cathode is placed outside of the extruded material. The gist of the present invention is a method for arranging a cathode for inner surface anodization on the center line of a slitted aluminum hollow extrusion, which is fixed by means of a method.

Example Next, embodiments of the invention will be described.

1 and 2, which disclose a method according to a first embodiment of the invention, the method according to the invention first comprises an aluminum hollow tube fixed to an electrolytic frame (not shown) and having a slit 4 along its entire length at its upper end. Inserting an inner surface anodizing cathode 3, at least a part of which is constituted by a spring 3a, into the extruded material 1;
Next, one end of the cathode 3 is hooked to the center of the insulating cathode hooking member 2 on the outside of one end of the extruded material 1 . Then, an insulating cathode suspension member 5 having a locking portion 6 at the upper end is inserted through the slit 4 into a required point in the middle of the length of the extruded material 1, and the intermediate part of the length of the cathode 3 is connected to the cathode suspension member. By suspending the lower end of the cathode 3 from the lower end of the spring 3a, the cathode 3 is placed on the center line of the hollow part 11 of the extruded material 1, and the other end of the cathode 3 is suspended from the spring 3a. By pulling the cathode 3 in the length direction against the force, the cathode latching member 2 is brought into contact with one end of the extruded material 1, and in this state, the other end of the cathode 3 is pushed outward by the extruded material 1. It is fixed by the arranged fixing means 13.

The hollow part 11 of the extruded material has a circular cross section,
The extruded material 1 has a rectangular outer shape in cross section, and the hollow portion 11 is eccentrically formed near the upper end.

The upper internal cathode 3 is made of aluminum, stainless steel, titanium, or the like. The internal cathode 3 is composed of a short spring 3a and a long rod-shaped or tubular cathode 3b.

The cathode hanging member 2 is made of a material having chemical resistance, heat resistance, and insulation properties, such as styrene resin, polyethylene resin, polyvinyl chloride resin, or the like. The cathode hanging member 2 has a trapezoidal plate shape, and has both side edges 2a,
2a has a tapered shape, passes through the center of the end face of the hollow portion 11 of the extruded member 1 having a circular cross section, and has a diameter larger than that of the end face.

The cathode hanging member 5 is made of the same insulating material as the cathode hanging member 2, and includes a locking portion 6 at the upper end that is locked to the upper wall of the extruded member 1, and a ring-shaped portion 7 at the lower end through which the cathode 3 is inserted. and a connecting portion 8 that connects the two.

The fixing means 13 is composed of a U-shaped member 14 and a bolt 15 with a handle 16 screwed through the upper horizontal wall 14a of the U-shaped member 14, and the right end of the internal cathode 3 is attached to the tip of the bolt 15. Therefore, by being held down by the lower horizontal wall 14b of the U-shaped member 14, the internal cathode 3 is pulled and fixed horizontally.

An auxiliary positioning member 18 made of an insulator is disposed at the right end of the slitted hollow extruded member 1 and is slidably fitted over the internal cathode 3. This has a trapezoidal plate shape, and its tapered side edges 18a, 18a are directed inward, and the extruded material 1
It is brought into contact with the inner peripheral edge of the right end surface at two points.
Note that the internal cathode 3 is inserted through a cylindrical portion 19 provided horizontally in the center of the auxiliary positioning member 18 . After the internal cathode 3 is fixed by the fixing means 13, the auxiliary positioning member 18 is slid and brought into contact with the right end of the extruded material 1, thereby making the positioning of the internal cathode 3 even more reliable. It is something that can be done.

3 and 4 show a second embodiment of the invention. Here, the difference from the first embodiment is that the outer shape of the hollow extruded material 1 with slits is circular in cross section, the hollow part 11 also has a smaller circular cross section, and the hollow part 11 is closer to the upper end. The internal cathode 3 is formed eccentrically at the center, the entire internal cathode 3 is constituted by the spring 3a, and the annular portion 7 at the lower end of the cathode suspension member 5 is short in order to support the middle portion of the spring 3a. This is due to its cylindrical shape.

A short fixing plate 17 is connected to the right end of the spring-like internal cathode 3, and a short fixing plate 17 is connected to the tip of the bolt 15 of the fixing means 13 and the lower horizontal wall 14b of the U-shaped member 14.
The fixing plate 17 is held down by.

The other points of this embodiment are the same as those of the first embodiment, and the same parts are given the same reference numerals in the drawings.

Note that the shapes of the slitted hollow extruded material 1, the cathode hanging member 2, and the cathode hanging member 5 are not limited to those shown in the drawings, and may have other shapes.

Effects of the Invention As described above, in the method of the present invention, at least a portion of the spring 3a is provided inside the aluminum hollow extruded member 1 having the slit 4 over the entire length at the upper end.
Insert a cathode 3 for internal anodic oxidation constituted by and hook one end of the cathode 3 to the center of the insulating cathode retaining member 2 on the outside of one end of the extruded material 1;
An insulating cathode suspension member 5 having a locking portion 6 at the upper end is inserted through the slit 4 into a required point in the middle of the length of the extruded material 1, and the intermediate portion of the length of the cathode 3 is inserted into the cathode suspension member 5. By suspending the cathode 3 from the lower end of the extruded material 1, the cathode 3 is placed on the center line of the hollow part 11 of the extruded member 1, and the other end of the cathode 3 is pulled in the length direction of the cathode 3 against the elastic force of the spring 3a. By tensioning, the cathode retaining member 2 is brought into contact with one end of the extruded material 1, and in this state, the other end of the cathode 3 is fixed by the fixing means 13 disposed outside the extruded material 1. The oxidizing cathode 3 can be placed precisely on the center line of the hollow part 11 of the slitted aluminum hollow extrusion 1, and therefore an anodic oxide film of uniform thickness can be formed on the inner surface of the extrusion 1. ,
The quality of the extruded material 1 can be improved, and sparks are not generated due to contact between the extruded material 1 and the internal cathode 3 during electrolysis, resulting in no defective products.

[Brief explanation of the drawing]

The drawings show two embodiments of this invention.
1 is a partially cutaway side view of the first embodiment, FIG. 2 is a front view thereof, FIG. 3 is a partially cutaway side view of the second embodiment, and FIG. 4 is a front view thereof. DESCRIPTION OF SYMBOLS 1... Aluminum hollow extrusion material with slit, 2... Cathode hanging member, 3... Internal cathode, 3a
... Spring, 4 ... Slit, 5 ... Cathode suspension member, 6 ... Locking part, 11 ... Hollow part, 13 ... Fixing means, 18 ... Auxiliary positioning member.

[Claims]

1 Add 10 to 60 g of sodium molybdate Na ₂ MoO ₄ 2H ₂ O to water as an anodized coloring film forming agent.
, ammonium molybdate (NH ₄ ) ₂ MoO ₄ is 5 to 80 g/, diammonium phosphate (NH ₄ ) ₂ HPO ₄ is 10 to 60 g/, and sodium fluoride NaF is 5 to 30 g/; or A method for anodizing and coloring titanium and titanium alloys, characterized by adding an inorganic compound higher than that and applying a direct current of 5 to 90 V at a temperature below 50°C.