JPH0469147A - Relatively equal speed polishing method - Google Patents

Abstract

PURPOSE:To uniformly polish each part of a face to be polished so as not to generate polishing unevenness by supporting a workpiece and polishing member so as not to be spun and swinging at least one of them in a specified pattern. CONSTITUTION:At least one polishing member 23 is pushed to at least one face 27a of a workpiece 27 to be polished at fixed force to fix the workpiece 27 and polishing member 23 so as not to be spun. In the next step, either the workpiece 27 or polishing member 23 is swung through a swing bar 25 so as to draw an arbitrary locus above a plane including a face 27a to be polished to polish the face 27a of the workpiece 27 to be polished.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polishing method particularly suitable for high-precision surface polishing and high-precision polishing of large workpieces.

[Conventional technology]

As a polishing machine for optical lenses, etc., a polishing machine typified by an Oscar type lens polishing machine is generally employed. FIG. 8 shows the basic configuration of such a polishing machine. As shown in this figure, the workpiece 2 is placed on the upper surface of the forced rotating plate l, which is a workpiece holding plate, and a vertical A polishing plate 4 is rotatably supported at the lower end of the swing rod 3.

During polishing, the polishing plate 4 is pressed against the workpiece by the swing rod, and in this state, the forced rotary plate starts rotating 10 times. At the same time, the swing rod swings left and right. As a result, the polishing plate 4 rotatably supported at the lower end of the rocking rod is given rotational motion by the rotation of the forced rotary plate 1.
It rotates on its own axis and swings over the surface of the workpiece, polishing the surface of the workpiece.

On the other hand, as a polishing machine of a type different from the above, a polishing machine called a Hoffman type or Lapmaster type is known. This type of polishing machine has the 9th [g (A), (B
), a planetary gear reduction mechanism is incorporated on the forced rotation polishing plate 11, and each planetary gear making up this reduction mechanism functions as a workpiece holding plate 13.
Here, a plurality of workpieces 14 are supported while being pressed against the polishing vi11 side. In the polishing machine having this configuration, when the polishing plate 11 rotates, the workpiece holding plate 13 rotates and revolves, and the workpiece 14 supported on the workpiece holding plate 13 is polished.

[Problem to be solved by the invention]

In any of these conventional polishing machines, the polishing plate polishes the workpiece while rotating on its axis. For this reason, when comparing the rotation center side and the outer peripheral side of the polishing plate, the polishing momentum on the outer peripheral side, where the peripheral speed is high, is much larger than the polishing momentum on the center side, where the peripheral speed is low. As a result, the amount of polishing differs between the part of the workpiece that is in contact with the center of rotation and the part of the workpiece that is in contact with the outer circumference, and there is a risk that highly accurate polishing operation cannot be expected. be.

Especially when the shape of the workpiece is rectangular or triangular,
The polishing momentum at corner portions located far from the center becomes large, making it difficult to polish the entire workpiece uniformly and accurately.

Furthermore, even when the machine rotational speed is increased to speed up the machining cycle, the difference in polishing momentum similarly increases, resulting in a significant drop in polishing accuracy. Furthermore, even when the workpiece becomes larger, the difference in polishing momentum increases due to this difference in peripheral speed.
In polishing machines such as the Lapmaster type, polishing accuracy cannot be improved unless the workpiece is polished using a polishing plate considerably larger than the workpiece.

Here, it is possible to increase the polishing accuracy by reducing the peripheral speed difference by reducing the machine rotation speed to an extremely low speed.
If this is done, the machining time will be long and it is not practical.

In view of the drawbacks of conventional polishing machines, an object of the present invention is to provide a polishing method in which the polishing momentum can be made substantially equal in each part, and thereby the polishing operation can be performed with high precision. The aim is to realize this.

[Means to solve the problem]

In order to solve the above problems, in the present invention, the workpiece and the polishing machine are moved relative to each other so that the polishing plate draws a substantially equal relative trajectory with respect to any part of the workpiece, thereby This makes it possible to perform polishing operations with high precision.

That is, in the polishing method of the present invention, at least one polishing member is pressed against at least one polished surface of the workpiece with a constant force, and each of the workpiece and the polishing member is prevented from rotating. and while maintaining this state, at least
It is characterized in that one side is oscillated so as to draw an arbitrary trajectory on the surface including the surface to be polished.

In addition, in the method of the present invention, the first and second polishing members are respectively applied to the first and second polished surfaces of the workpiece located at opposing positions, with the workpiece sandwiched between them. While pressing with force, the workpiece and the first and second
Each of the polishing members is fixed so as not to rotate, and in this state, the workpiece side, the first and second polishing member sides, or both sides are connected to the first polished surface. It is characterized in that it is made to swing so as to draw an arbitrary locus on a surface including the second surface to be polished and on a surface including the second surface to be polished.

[Effect]

In the method of the present invention, no rotational motion occurs on either side of the workpiece or the polishing member during polishing.

For this reason, the relative trajectories between each part of the polished surface of the workpiece and the polishing member are substantially equal. As a result,
The polishing momentum in each part of the surface to be polished is also equal, and each part is polished uniformly. In other words, highly accurate polishing is performed.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

1 to 5 illustrate examples of polishing machines that perform polishing operations according to the method of the present invention. First, as shown in FIGS. 1 to 3, the polishing machine 21 of this example includes a surface plate 22 fixed at a fixed position, and a polishing plate 23 fixed on the upper surface of the surface plate 22.
and a work holding plate 24 suspended in a position directly above the polishing plate facing the polishing plate. A swinging rod 25 is vertically supported on the upper side of this work holding plate 24 by a machine frame (not shown), and is pivoted about this by a pivot 25a formed at the lower end of this swinging rod 25. Possibly, the work holding plate 24 mentioned above is suspended. A workpiece 27 is fixedly supported on the lower surface of this workpiece holding plate 24 .

Here, a groove 24a passing through the center of swing is formed on the upper surface of the workpiece holding plate 24, and a detent member 26 fixed to the swing rod 25 is placed in the groove on both sides of the center of swing. The engaging claws 26r and 26f are fitted.

The above-mentioned swing rod 25 can be raised and lowered by a lifting mechanism (not shown). Such a lifting mechanism can be easily constructed by a person skilled in the art by using a drive mechanism such as an air cylinder, and similar mechanisms are used in polishing machines in the field, so please refer to the detailed explanation below. Explanation will be omitted.

The workpiece 27 to be polished is pressed against the polishing plate 23 with a constant force by the lifting mechanism.

In addition, as shown in FIG.
It is designed to move along a trajectory that draws a rectangular shape as a whole while drawing a circle at a constant pitch.

FIG. 4 shows an example of a drive mechanism suitable for driving the rocking rod along the heel trajectory. This drive mechanism 31 is a two-wheel slide mechanism, and a ball screw 32 extending in the X direction is provided on one opposite side of the four sides assembled in a rectangle.
and a guide rod 33 are supported, and similarly a ball screw 34 extending in the X direction is provided on the opposite side on the other side.
and a guide rod 35 are supported. An X-direction moving rod 37 extending in the X direction is supported between the ball screw 32 and the rod 33, and an X-direction moving rod 38 extending in the X direction is supported between the ball screw 34 and the rod 35. There is.

The X-direction moving rod 37 and the X-direction moving rod 38 extend slidably through the slider 39, respectively. This slider 39 includes the aforementioned swing rod 25.
The upper end side of is supported.

On the other hand, each ball screw 32, 34 is connected to a motor 41, respectively.
, 42.

In the drive mechanism 31 configured in this manner, the slider 39 can be moved to any position on a plane by controlling the drive of each motor 41, 42 by a sequencer or a microcomputer. In other words, move the slider 3 along an arbitrary trajectory on the plane.
9 can be moved, and thus the swinging rod 25 supported thereon can be moved along the trajectory shown in FIG.

In the polishing machine 21 of this example configured as described above, first, as shown in FIGS. Press with force. In this state, the swing rod 25 is swung along the trajectory shown in FIG. 3 by a drive mechanism as shown in FIG. 4. During this rocking movement, the rocking rod 2
The workpiece holding plate 24 supported on the lower end side of the frame 5 is prevented from rotating by the rotation stopper member 26.
It draws the same trajectory together with the swinging rod 25 without rotating. On the other hand, since the polishing plate 23 side is fixed to the surface plate 22 side, even if the workpiece holding plate 24 and the workpiece 27 move, they do not rotate or otherwise move. As a result, at each point on the polished surface 27a of the workpiece 27, the locus of relative movement with respect to the polishing plate 23 becomes the same, and the pattern shown in FIG. 5 is drawn. Therefore, the polishing momentum at each point on the surface to be polished 27a is equal, and therefore,
Uniform and precise polishing is performed.

In the above example, the side of the workpiece 27 is rocked, but instead of this, the side of the polishing plate may be rocked. In this case, it is necessary to fix the workpiece so that it does not rotate. Alternatively, both may be oscillated together. Further, the trajectory of the swinging rod may be any pattern (for example, the trajectory shown in FIGS. 6 and 7 can be cited).

Furthermore, in the above example, the surface to be polished of the workpiece 27 is one surface, and therefore there is only one polishing plate, but a large number of polishing surfaces may be simultaneously polished by a plurality of polishing plates. Of course.

On the other hand, the above example is an example in which the method of the present invention is applied to a polishing machine that polishes one surface of the workpiece 27. It is also possible to apply the method of the present invention to. In this case, the workpiece may be fixed at a fixed position, and the polishing plates pressed above and below the workpiece may be oscillated so as to draw a constant trajectory without rotating. Alternatively, the side of the polishing plate may be fixed at a fixed position so as not to rotate or oscillate, and the side of the workpiece may be oscillated along a fixed pattern of loci without rotating. Bye.

(Effects of the Invention) As explained above, in the method of the present invention, the workpiece and the polishing member are supported so as not to rotate, and at least one side is caused to swing in a predetermined pattern. Therefore, according to the method of the present invention, since the polishing plate follows a substantially equal relative trajectory with respect to any part of the workpiece, the rotational motion on the side of the workpiece or the polishing member is avoided. It is possible to avoid the situation where uneven polishing occurs due to differences in circumferential speed. Therefore, each part of the surface to be polished can be uniformly polished, and it is possible to perform a highly accurate polishing operation. Therefore, By adopting the method of the present invention, high-precision polishing can be performed at high speed, high-precision polishing of large workpieces can be easily performed, and highly accurate polishing can be performed regardless of the shape of the workpiece. be able to.

[Brief explanation of drawings]

FIG. 1 is a front view showing a schematic configuration of a polishing machine to which the method of the present invention is applied, FIG. 2 is a schematic side view of the polishing machine shown in FIG. 1, and FIG.
The figure is an explanatory diagram showing the locus of the swinging rod of the polishing machine in Figure 1, and Figure 4.
The figure is a schematic configuration diagram showing the drive mechanism of the rocking rod in the polishing machine of Figure 1, Figure 5 is a line diagram showing the relative locus of the workpiece and polishing plate in the polishing machine of Figure 1, Figures 6 and FIG. 7 is a diagram showing another example of the relative trajectory between the workpiece and the polishing plate, FIG. 8 is a schematic diagram showing the configuration of a conventional polishing machine, and FIG.
Figures (A) and (B) are a schematic side view and a schematic plan view showing the configuration of another conventional polishing machine. [Explanation of symbols] 21... Polishing machine 23... Polishing plate... Work holding plate... Rocking rod... Rotation stopping member... Workpiece a... Surface to be polished... Swing rod drive mechanism. Figure 4 Figure 7 Figure 8 Figure 5 Exploration Figure 6 Figure 9

Claims (2)

[Claims] (1) Pressing at least one polishing member against at least one surface to be polished of the workpiece with a constant force, fixing each of the workpiece and the polishing member so as not to rotate, the workpiece and At least one side of the polishing member is oscillated so as to draw an arbitrary trajectory on a surface including the surface to be polished, and the surface to be polished of the workpiece is polished at a relative constant velocity. Polishing method. (2) Pressing the first and second polishing members with a constant force against the first and second polished surfaces of the workpiece located at opposing positions, respectively, with the workpiece sandwiched therebetween, and The workpiece and each of the first and second polishing members are fixed so as not to rotate, and at least one side of the workpiece and the first and second polishing members is fixed to the workpiece and the first and second polishing members. polishing the first and second surfaces of the workpiece by swinging it so as to draw an arbitrary trajectory on a surface including the first surface to be polished and a surface including the second surface to be polished; This is a relative constant speed polishing method.