JP2001170856A - Curved surface finishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curved surface finishing device for efficiently and accurately polishing a work having a complex curved surface such as a turbine blade. SOLUTION: This device comprises a tilting roller 4 having a tilting shaft for rotating the roller attitude in a vertical direction in relation to a running direction of a polishing belt 1 and contacting with the polishing belt 1, between spans of the work contacting with a free-belt type belt polisher for pressing the work 5 against the polishing belt 1 wound around a drive wheel 2 and a driven wheel 3 for polishing. The device tilts according to tilting of the work surface as the polishing belt is pressed against the work thereby pressing the polishing belt against along the curved surface of the work to polish it with adapting naturally to the curved surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curved surface finishing apparatus for grinding and polishing a free curved surface, and more particularly to a curved surface finishing apparatus for performing surface finishing of a member having a saddle shape using a polishing belt.

[0002]

2. Description of the Related Art Heretofore, for finishing a member having a complicated three-dimensional curved surface such as a turbine blade, a method of performing finish polishing by a belt polishing machine has been often used. When using a contact wheel type belt polishing machine that grinds while pressing a contact wheel around which a polishing belt is wound on a workpiece, pressing the contact wheel while polishing at the pitch according to the finished shape and polishing can achieve an arbitrary shape. Can be well formed. However, this method stops and polishes during pitch feeding, so that wheel marks are easily generated, and it has been difficult to finish the work surface smoothly. In particular, for a member such as a turbine blade in which the shape accuracy of the convex surface is important, it is necessary for a skilled worker to reduce the feed pitch of the work, process it for a long time, and then perform more precise finishing.

On the other hand, when a free belt type belt polisher that polishes by pressing an intermediate position of a polishing belt that is tensioned between rollers against a work is used, the processing efficiency is relatively low, and it takes time to finish. Is relatively good. However, when finishing a work having a complicated three-dimensional shape as shown in FIG. 8, if the polishing surface of the work is inclined with respect to the pressing direction of the polishing belt, the polishing belt may deviate from the processing surface. Stable finishing cannot be performed due to stepping due to one-sided contact. Therefore, the work must be performed while adjusting the support posture of the work so that the polishing surface of the work and the polishing belt are substantially parallel. For this reason, there is a problem that a workpiece gripping device becomes complicated particularly when handling a workpiece having a complicated three-dimensional curved surface such as a turbine blade having a convex surface having a warp in a longitudinal direction and having a saddle shape.

A belt polishing machine which eliminates the disadvantage that a wheel mark is generated when polishing with a single contact wheel wound with a polishing belt is disclosed in Japanese Patent Laid-Open Publication No. Sho 51-151.
No. 109598 discloses this. The belt polisher disclosed in this publication uses two contact wheels. When processing a flat surface, the surface of the work is processed close to the contact line of the contact wheel, and when processing a convex surface, two pieces are used. Switching to the free belt method sandwiched between the contact wheels, adjusting the distance between the two contact wheels according to the convex shape of the work, and changing the curvature at the position of contact with the work using the flexibility of the polishing belt to optimize processing I do. According to the disclosed belt polisher, it is possible to efficiently perform highly accurate polishing of a workpiece having a complicated convex curved shape without generating a wheel mark.

However, even when such a belt polishing machine is used to process a wide workpiece having a warped convex surface while shifting the workpiece in the width direction of the polishing belt,
In order to prevent the polishing belt from shifting during processing, the work must be polished while adjusting the posture of the work so that the polishing surface of the work is always parallel to the surface of the polishing belt. The structure becomes complicated, and the operation also requires skill. In addition, when polished with a belt polisher, the polished surface is dense and the finish is good, but when the grinding depth is large, it takes time and efficiency is poor.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a curved surface finishing apparatus for efficiently and accurately polishing a work having a complicated curved surface.

[0007]

In order to solve the above-mentioned problems, a curved surface finishing apparatus according to the present invention comprises a driving wheel, a driven wheel, and a tension wheel, and is provided at a position sandwiched between wheels of a polishing belt wound around these wheels. A free-belt type belt polishing machine for pressing and polishing a work, comprising a tilting roller having a roller which rotates freely in contact with a polishing belt during a span in contact with the work. This tilting roller has a tilting axis for rotating the roller in a direction perpendicular to the running direction of the polishing belt, and is constantly pressed against the polishing belt, so that the polishing belt is pressed against the work and corresponds to the work surface. Lean as you lean. For this reason, the polishing belt is pressed along the curved surface of the work while slightly deviating from the orbit extended by the wheels at both ends of the work area,
Polish naturally following a curved surface.

[0008] The tilting roller may be one in which two free rotating rollers are installed in parallel. The tilting roller using the parallel rotating roller has two tilting axes that are substantially perpendicular to each other, and is tilted in two directions perpendicular to and parallel to the running direction of the polishing belt, so as to be substantially perpendicular to the inclined surface of the polishing belt. It can be abutted. By automatically setting the contact surface to be perpendicular to the inclination of the polishing belt, an appropriate contact pressure can be generated by automatically following the inclination even if the curved surface of the work changes.

[0009] The curved surface finishing apparatus of the present invention can further include a grinding apparatus using an elastic grinding wheel on the upstream side to polish a work surface having a three-dimensional curved surface. For a workpiece having a large polishing allowance, it is preferable to perform rough polishing in advance using a highly efficient grinding wheel and then perform precise polishing using a belt polishing machine. Since the shape of the grinding wheel changes in accordance with the shape of the workpiece, the elastic grinding wheel has a high machining efficiency although the processing surface is slightly rough. A method of roughly adjusting the shape of a work with a grinding wheel and finishing a thin layer on the surface with a polishing belt enables efficient and precise polishing.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments with reference to the drawings.

[0011]

FIG. 1 is a perspective view showing an essential part of a curved surface finishing apparatus according to one embodiment of the present invention, FIG. 2 is a sectional view showing an example of a tilting roller used in the present embodiment, and FIG. FIG. 4 is a perspective view showing an example of a work supporting device to be used, FIG. 4 is a plan view illustrating the operation of the present invention, and FIG. 5 is a cross-sectional view illustrating the operation of the present invention.

In the curved surface finishing apparatus of the present embodiment, as partially shown in FIG. The work 5 is placed in a free belt region between the and the driven wheel 3, and the work surface is polished by pressing the abrasive grain surface of the rotating polishing belt 1. The pressing force of the polishing belt 1 can be adjusted by the tension applied to the belt by the tension wheel.

A feature of the present invention resides in that a tilting roller 4 is provided between a work 5 and a driving wheel 2 or a driven wheel 3. FIG. 2 shows one of the tilt rollers 4 used in this embodiment.
It is sectional drawing which shows an example. The tilting roller 4 is used for the polishing belt 1.
And a roller box 13 that freely tilts with respect to a support member 12 that presses the roller 11. Roller box 13
Is rotatably attached to a pivot member 14 via a pivot shaft 15, and the pivot member 14 is pivotably attached to the support member 12 via a second pivot shaft 16. The two rotating shafts 15 and 16 are configured to be substantially orthogonal to each other, and when the surface of the polishing belt 1 is inclined, the attitude of the roller box 13 changes according to the inclination.

The work 5 for surface polishing is, for example, shown in FIG.
Is fixed to the work supporting device 6 as shown in FIG. The work supporting device 6 is a device that fixes the work 5 by sandwiching the work 5 in a direction perpendicular to the polishing direction and rotating the work 5 by the handle 21 or remote control to shift the position. The work supporting device 6 is movable on the rails 22 and can change the polished portion of the work 5 in a direction transverse to the polishing belt 1.

The polishing belt being polished has the shortest belt length between the driving wheel and the driven wheel as the tension of the tension wheel is adjusted, and is stabilized in a state where the tension is the smallest. Therefore, when the work surface is inclined with respect to the polishing belt, the polishing belt indicated by a dotted line in FIG. 4 tends to move in a direction in which the work surface is lowered as indicated by a chain line.
Furthermore, since the polishing belt is driven by being stretched horizontally in a direction connecting the tangents of the driving wheel and the driven wheel installed in parallel with each other, when the surface of the work disposed between the wheels is inclined, the surface is high. In some cases, a stronger polishing force acts on the polished surface, as shown by a dotted line in FIG. Therefore, when the surface of a work is polished by a conventional belt polisher, the work has to be performed while adjusting the posture of the work so that the polished surface is parallel to the polishing belt. Therefore, the work supporting device also needs to have a structure that allows the posture of the work to be freely changed in accordance with the profile in the transverse direction of the polishing belt. And had problems with handling.

However, in the curved surface finishing apparatus of the present embodiment, since the tilting roller 4 that can tilt freely is interposed, if the surface of the work 5 is tilted, the polishing roller 1 tilts following the surface. Roller 11 is the polishing belt 1
Polishing belt 1 autonomously tilts in the same direction corresponding to the tilt of
4 and 5, the surface of the polishing belt 1 is pressed against the surface of the work 5 in a direction perpendicular to the surface of the work 5 as shown by a solid line in FIG. 4 and FIG. can do. Further, since the polishing belt 1 is pressed in parallel to the surface of the work 5, the polishing amount is not uneven and uniform polishing can be performed.

In this way, even if the surface of the work 5 is inclined, uniform processing can be performed. Therefore, the work 5 is simply moved in a direction transverse to the polishing belt 1 while being fixed to the work support device 6. Since the polishing can be naturally performed in accordance with a complicated shape simply by performing the operation, the structure of the work supporting device 6 may be a simple one that only linearly moves on the rail 22. Note that even if the tilting roller 4 is tilted, the polishing belt 1
It is preferable that the length of the roller is longer than the width of the polishing belt 1 in order to ensure stable operation by preventing the roller from coming off the roller.

[0018]

Embodiment 2 FIG. 6 is a side view for explaining the principle of a second embodiment of the curved surface finishing apparatus according to the present invention, and FIG. 7 is a sectional view showing an example of a tilting roller used in this embodiment. The second embodiment differs from the first embodiment in that the tilting roller has two rollers and two rotating shafts, whereas the tilting roller has only one roller and one rotating shaft. Therefore, in the present embodiment, elements having the same function are denoted by the same reference numerals, and the description is simplified. In the curved surface finishing apparatus of the first embodiment, the tilting roller changes its attitude three-dimensionally, regardless of the shape and orientation of the polishing surface of the work, and regardless of the position of the tilting roller and the tilt angle of the polishing belt. The amount of twist of the polishing belt is divided into two so that the polishing belt comes into contact with the work substantially perpendicularly. However, when the workpiece does not have an extreme shape, it is sufficient to incline in a plane perpendicular to the running direction of the polishing belt.

In this embodiment, the polishing belt 1 is stretched around a driving wheel 2, a driven wheel 3, a tension wheel 7, and a tilting roller 11. The work 5 is placed between the drive wheel 2 and the tilting roller 11, and grinds the running polishing belt 1 by pressing it against the surface of the work. The tension wheel 7 raises the running polishing belt 1 to the outside by the moment due to the balance 8 and adjusts the tension, thereby adjusting the polishing force on the work 5.
In the tilting roller 4 used in the present embodiment, one roller 11 is mounted in a roller box 13.
The roller box 13 is connected to the support member 12 via the rotation shaft 15.
Is mounted to be rotatable. Therefore, when the pressed polishing belt 1 is inclined, the roller 11 rotates in a plane about the rotation shaft 15 according to the inclination.

In the polishing operation, the work 5 is supported on a support device (not shown), and as the portion in contact with the polishing belt is polished, the workpiece 5 is gradually moved in a direction perpendicular to the polishing belt 1 to polish a new portion. Eventually, the polishing is completed by finishing the polishing of the entire polishing surface of the work 5. When the surface of the workpiece 5 is inclined while the workpiece supporting device advances vertically with respect to the polishing belt 1,
The polishing belt 1 is pressed against the surface of the work and is inclined according to the inclined surface. When the polishing belt 1 is tilted, the tilting roller 11 is pushed by the polishing belt 1 and autonomously tilts in the vertical plane, so that the polishing belt 1 maintains an appropriate tilt and maintains contact with the surface of the work 5. Polishing. The structure of the tilting roller 4 according to the present embodiment is simpler in structure than that used in the first embodiment, and is therefore more economical.

In any of the above embodiments, the same effect can be obtained even if the tilting roller 4 is placed between the driven wheel 3 and the work 5, and the work 5 is sandwiched between the two tilting rollers 4. By placing them on both sides, the engagement between the polishing belt 1 and the surface of the work can be ensured, and a higher quality polishing process can be performed.

For a workpiece having a large grinding allowance,
As a pre-process of free belt polishing using the tilting roller of the present invention, high-efficiency rough grinding along a curved surface of a workpiece using an elastic grindstone formed by laminating abrasive grains around a disk made of an elastic body such as a sponge. Is preferably performed. The elastic grindstone is formed by forming an elastic body in a ring shape and forming an abrasive layer on the outer periphery of which is cut in a lump. The elastic grindstone is pressed against a workpiece while being rotated as a grinding wheel to perform grinding. If the surface of the work has a curved surface, the elastic body is deformed, so that the grinding can be performed to some extent following the curved surface, though not as much as the polishing belt. Since the abrasive layer of the elastic grindstone is sufficiently hard, the grinding efficiency is remarkably higher than that of the polishing belt. However, since it does not have the same profiling property as the polishing belt, a precise finished shape cannot be obtained. Therefore, a two-stage grinding method that performs rough grinding following a curved surface with an elastic whetstone and then performs precision grinding on the obtained rough surface with a grinding belt using a tilting roller has improved work efficiency and high quality. It is effective for securing.

[0023]

As described above, according to the curved surface finishing apparatus of the present invention, even when a complicated work such as a turbine blade is to be processed, the grinding process is performed in accordance with the curved surface of the work. Polishing can be performed with high precision by a simple operation that does not require any skill, without generating marks or the like. Further, by using an elastic grindstone together, a remarkably high efficiency polishing finish can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a curved surface finishing device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating an example of a tilting roller used in the first embodiment.

FIG. 3 is a perspective view showing an example of a work supporting device used in the present embodiment.

FIG. 4 is a plan view illustrating the operation of the present invention.

FIG. 5 is a cross-sectional view illustrating the operation of the present invention.

FIG. 6 is a side view for explaining the principle of a second embodiment of the curved surface finishing device of the present invention.

FIG. 7 is a sectional view showing an example of a tilting roller used in a second embodiment.

FIG. 8 is a perspective view showing a main part of a conventional curved surface finishing device.

[Explanation of symbols]

 Reference Signs List 1 polishing belt 2 drive wheel 3 driven wheel 7 tension wheel 5 work 4 tilting roller 11 roller 12 support member 13 roller box 15, 16 rotation shaft 14 rotation member 6 work support device 21 handle 22 rail 8 balance

Continued on the front page (72) Inventor Masahiro Shimada 118 Futatsuka Noda City, Chiba Prefecture Kawasaki Heavy Industries Noda Factory Co., Ltd. (72) Inventor Takeo Iida 118 Futatsuka Noda City Chiba Prefecture Kawasaki Heavy Industries Noda Factory F Term 3C058 AA02 AA05 AA12 AA16 AB04 CA03 CB01 CB03

Claims (3)

[Claims] 1. A free-belt type belt polishing machine comprising a driving wheel, a driven wheel, and a tension wheel, which presses a workpiece to a position sandwiched between wheels of a polishing belt wound around these wheels to polish the workpiece. A tilting roller having a roller that freely rotates in contact with the polishing belt during the span of the polishing belt, wherein the tilting axis of the tilting roller is tilted in a direction perpendicular to the running direction of the polishing belt, whereby the tilting roller is rotated. Characterized in that the polishing belt presses the polishing belt according to the inclination of the polishing belt generated corresponding to the work. 2. A second free rotation roller having a rotation axis parallel to a rotation axis of the free rotation roller, and a second tilt shaft for tilting in a direction parallel to a running direction of the polishing belt. The curved surface finishing device according to claim 1, further comprising: 3. The surface finishing device according to claim 1, further comprising a grinding device further using an elastic grinding wheel on an upstream side to polish a work surface having a three-dimensional curved surface.
The described surface finishing device.