JPS61297074A - Polishing of metal curved article and apparatus thereof - Google Patents

Abstract

PURPOSE:To press-attach the nonwoven polishing cloth installed onto the surface of a bag uniformly onto the whole curved surface of a polished workpiece through nonteaching, by pouring liquid into the bag installed in expandable ways between back-up jigs and the polished workpiece. CONSTITUTION:A turbine blade 1 is arranged between a pair of back-up jigs 9, and a bag 10 interposed between the back-up jigs 9 and the turbine blade 1 is expanded by pouring liquid into the bag 10, and the nonwoven polishing cloth 12 on the surface of the bag 10 is pressed and closely attached uniformly onto the whole curved surface of the turbine blade 1. In this state, direct current is allowed to flow, dripping electrolytic liquid 3 onto a grinding point, and a blade installation board 7 is swung by an eccentric cam 8. Thus, the composite grinding consisting of slidable polishing and electrolytic polishing can be applied onto the turbine blade 1.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a polishing method and a polishing apparatus that are applied to surface finish polishing of two-dimensional and three-dimensional metal curved bodies.

<Prior art> Turbine blades with three-dimensional curved surfaces, such as rods for oil cylinders with two-dimensional curved surfaces and rotating shafts of various machine tools, are processed by cutting the surface using several fffl 1t IIJ controls. Needs to be sanded down. - As an example, in the case of the turbine blade 1 shown in FIG. 7, the unevenness (pick tweed) on the surface after cutting is about 50 to 100 μm, so it is necessary to finish it to 3 to 6 μm by final polishing.

(1) Conventionally, as shown in Fig. 8, the final polishing method involves a skilled worker manually pressing the turbine blade 1 in the direction of the arrow 03 against an endless belt sander 02 wound around a rotating roll 01 to remove the splinters. are doing.

(2) Another method is to use a fixed grinder 04 as shown in FIG.
On the other hand, there is also a method in which the blade root 2 is held by the blade 05 attached to the tip of the arm 06 and pressed against the turbine blade 1'tl''.

(3) Furthermore, recently, a composite polishing method has been proposed that utilizes the synergistic effect of electrolytic polishing and abrasive polishing, which is a promising high-efficiency and high-precision polishing method. is used as an anode, and the tool electrode 4 opposite to this is used as a negative electrode, a nonwoven fabric beam with abrasive particles attached to the tool electrode 4, and this nonwoven fabric 5 is brought into contact with the workpiece 3 and rotated, and an electrolytic solution mixed with the abrasive particles is applied. There is a method of polishing the workpiece 3 while flowing it from the pump 6. In addition, 1-1 in the figure is the leading edge,
1-2 is the trailing edge, 1-3 is the wing back, 1-4
2a is the wing abdomen, and 2a is the Christmas tree (fitting part).

<Problems to be Solved by the Invention> In the above-mentioned prior art, (1) in the case of manual finishing by skilled workers, the first problem is that the work cannot be progressed due to a shortage of skilled workers, the working environment is poor, the fatigue of the workers increases, The disadvantage is that the quality of the finish varies. In addition, (2) in the case of final polishing by a robot, the polishing situation is not good due to the long teaching time to the robot, wear of the grinder, and poor precision of the robot; Since the grinding is performed using a grinder, it is necessary to narrow the width of the grinder, resulting in a decrease in efficiency, and a small-diameter grinder is required to grind the blade abdomen 1-4. Furthermore, (3) combined polishing of electrolytic polishing and abrasive polishing has the disadvantage that since the tool pole is made of a metal block of a predetermined shape, polishing can only be applied to one-dimensional and two-dimensional surfaces.

In view of the above-mentioned drawbacks, the present invention provides a method and a polishing apparatus for polishing a curved metal surface, which does not require manual work by skilled workers, does not require the teaching time required by conventional robot operations, and does not involve complex polishing using electrodes of a predetermined shape. The purpose is to provide.

<Means for Solving the Problems> The present invention, which achieves the above-mentioned objects, has the following features: (1) A material that can be freely expanded and contracted by adjusting the injection of fluid pressure, and can be polished on the surface facing the material to be polished. A bag to which cloth is glued is interposed between the material to be polished and the backup filter to adjust the contact pressure between the material to be polished and the polishing cloth, and to create relative motion at the interface between the material to be polished and the polishing cloth. (2) An expandable and contractible structure is formed between the outer surface of the bag, which can expand and contract freely by adjusting the injection of fluid pressure, and the abrasive cloth bonded to the surface facing the material to be polished. and a flexible conductive layer is formed, a negative electrode of a DC power source is connected to the conductive layer, a positive electrode is connected to the material to be polished, and an electrolytic solution is supplied to the material to be polished. do.

<Operation> By injecting fluid into the expandable bag, the felt-like nonwoven fabric on the bag surface uniformly presses the curved surface of the material to be polished over the entire surface via the backup jig. By changing the internal pressure of the lug, the pressing force can be changed depending on the surface curvature and surface roughness of the material to be polished.

Furthermore, by moving the material to be polished relative to the bag, the nonwoven fabric surface can be moved while keeping in constant contact with the surface of the material to be polished, so that uniform and highly precise polishing can be achieved over the entire surface. In particular, in the case of dry polishing, the abrasive power can be maintained by periodically reducing the fluid pressure to shrink the bag, inserting abrasive grains into the gap between the nonwoven fabric and the workpiece, and polishing after applying fluid pressure. Become.

In the case of electrolytic composite polishing, conduction is established between the bag and the nonwoven fabric, which can be expanded/contracted or bent, or between the conductive layer and the material to be polished through the abrasive mixed electrolyte, so that the electrolytic polishing effect can be obtained. can.

Note that since the conductive layer is adhesively formed with conductive rubber, conductive plastic thin film, or metal foil, it behaves in accordance with the pressed shape of the bag.

<Example> The present invention will now be described in detail with reference to FIGS. 1 to 6. In FIG. 1, the blade mount 7 can be moved up and down by, for example, an eccentric cam 8, and is swung downward by -L as the eccentric cam 8 rotates. In FIG. 1, guides for vertical movement are omitted. This blade mounting base 7
The Christmas tree 2a of the turbine blade 1 is fitted into the blade, and the blade is set upright.

On the other hand, on both sides of the fixed turbine blade 10, a pair of opposing backup jigs 9 are arranged so that the interval between them can be adjusted. 10 stretchable bags
is mediated. The bag 10 has a mouthpiece through which fluid can enter and exit, and is communicated with a fluid source (not shown) via a compressor, pump, and pressure regulating valve (not shown). As shown in FIG. 3, the surface of the bag 10 is bonded with a conductive layer tOa made of stretchable conductive rubber, conductive plastic, copper foil with excellent bending elongation, etc., and the surface of the conductive layer 10a is Furthermore, a nonwoven fabric 12 to which abrasive grains are attached is attached.

Further, a DC power supply DC is electrically connected so that the blade root 2 becomes a positive electrode and the conductor layer 10a becomes a negative electrode. Then, an electrolytic solution 13 mixed with abrasive grains is dripped from above the interface of the nonwoven fabric 12 on the pair of expanded bags 10 to permeate. The electrolytic solution 13 and the abrasive grains are collected from the lower part, homogenized in the tank 11 by a stirring propeller, and circulated through the pump P.

During polishing, the contracted bag 10 shown in FIG. Composite polishing consisting of sliding polishing and electrolytic polishing is performed by swinging the blade constriction joint 7 at.

The blade mounting stand 7, the bag 10, the backup jig 9, etc. are sufficiently long in the front and back directions at right angles to the drawing in FIG. 1, and productivity can be improved by simultaneously grinding a plurality of blades.

Next, an example of two-dimensional polishing is shown in FIGS. 4 and 5. A nonwoven fabric 12 is brought into contact with the outer peripheral surface of a cylindrical body 14 installed on a lathe 15 via a backup jig 9 and a bag 10. In this manner, by rotating the lathe 15, a relative movement is given to the cylindrical body 14 and the nonwoven fabric 12, and a two-dimensional surface can be polished in the same manner as in the above-described embodiment. In this case as well, 130 drops of electrolyte solution are dropped, and the negative electrode of the electrode is placed on the cylindrical body 14.
A positive electrode is connected to the conductor layer 10a.

In addition, FIG. 6 shows the workpiece 1 in the embodiment shown in FIG.
The relative motion between the polishing cloth and the polishing cloth is changed from vertical swinging to rotation. That is, one side of the bag-up jig 9 is formed as an outer cylinder 20 and the other side as an inner cylinder 21 in a concentric shape,
The blade mounting base is a rotating table 22, and an inner bag 23a and an outer bag 23 are installed according to the inner and outer cylinders.
b is also formed into a cylindrical shape. By attaching a plurality of blades 1 on the table 22, highly efficient polishing is possible. By separating the inner tube 21 from the turning table 22 like the outer tube, twisting of the bag 23a can be prevented. This method has the advantage of being able to uniformly polish down to the blade root compared to the swinging method. Electrolyte 13, electrode connection, back pressure system (
(not shown) is the same as the above case.

In the above example, electrolytic composite polishing is used, but dry abrasive polishing may also be used. In this case, the conductor layer of the bag, the electrode connection, etc. are not necessary, but the addition of abrasive grains is required. This addition of abrasive grains intermittently causes the bag to expand and contract, and when the bag contracts, the abrasive grains are dropped and inserted into the gap between the material to be polished and the nonwoven fabric.

<Effect of the invention> As described above, the present invention has the following effects.

(b) By injecting fluid into a stretchable bag between the backup jig and the material to be polished, the abrasive nonwoven fabric attached to the surface of the parag can be pressed and adhered to the curved surface of the material to be polished uniformly over the entire surface without teaching.

(b) By causing relative movement between the polishing nonwoven fabric and the material to be polished at the interface thereof, the surface of the material to be polished is polished.

(c) A conductive layer is provided between the bag surface and the surface of the abrasive nonwoven fabric, the material to be polished is used as an anode, the conductive layer is used as a negative electrode, a DC potential is applied between the two, and an electrolytic solution containing abrasive grains is permeated into the nonwoven fabric part. At the same time, by applying internal pressure to the bag and enveloping the non-woven fabric surface over the entire surface of the material to be polished, and moving them relative to each other, it is possible to polish the curved surface of the material to be polished with uniform sieving accuracy (low Ili roughness) and high speed polishing. becomes.

[Brief explanation of the drawing]

1 to 6 show embodiments of the present invention; FIG. 1 is a cross-sectional configuration diagram of an example; FIG. 2 is a cross-sectional configuration diagram when the bag is deflated;
Fig. 3 is a sectional view taken along the line A-A in Fig. 1, Fig. 4 is a cross-sectional configuration diagram of an example of polishing a cylindrical object, and Fig. 5 is a sectional view taken along the line B-B in Fig. 4.
6 is a cross-sectional view of another example, FIG. 7 is a perspective view of an example of a turbine blade, FIG. 8 is a diagram of the polishing state when manual polishing is performed, and FIG. 9 is a robot-based polishing state. 10 is a diagram showing the state of conventional composite polishing. In the figure, 1 is a turbine blade, 7 is a blade mounting base, 8 is an eccentric cam, 9 is a backup jig, 10 is a back, 10a is a conductor 1-1, 12 is a nonwoven fabric, 13 is an electrolyte, 14 is a cylindrical body, 20 21 is an outer cylinder, 22 is a turning table, 23a is an inner bag, and 23b is an outer bag.

Claims (2)

[Claims] (1) A bag that can expand and contract freely by adjusting the injection of fluid pressure and has an abrasive cloth glued on the surface facing the material to be polished is interposed between the material to be polished and the backup jig, and the bag is A method for polishing a curved metal surface, characterized in that the contact pressure between the material and the polishing cloth is adjusted to generate relative motion at the interface between the material to be polished and the polishing cloth. (2) A stretchable and flexible conductive layer is provided between the outer surface of the bag, which can expand and contract freely by adjusting the injection of fluid pressure, and the polishing cloth, which is bonded to the surface facing the material to be polished. An apparatus for polishing a curved metal surface, characterized in that a negative electrode of a DC power source is connected to the conductor layer, a positive electrode is connected to the material to be polished, and an electrolytic solution is supplied to the material to be polished.