JPS618269A - Curved-face polishing machine - Google Patents

Abstract

PURPOSE:To obtain desired curved-face in short time, in polishing of curved-face such as an optical lens, by rotating a tool shaft fixed with a tool having spherical tip forcefully thereby providing the angle detecting function and rolling motion onto a work. CONSTITUTION:A work 5 having predetermined shape is set then rotated through a motor 7 while detecting the angular position to be removed upto such angle as corrected while considering the curvature of tool 11 at the tip through inclination angle detector 9. Upon determination of angle, the tool shaft 12 is pressed with constant pressure to perform polishing for predetermined time while rotating the tool 11 and the work 5 forcefully. In order to remove the shape smoothly, the work 5 is rolled with predetermined swing angle around the approximate axis 8 of curved-face by means of a pulse motor 16. Upon completion of removing work at predetermined angular position, it will proceed continuously to removing work at different angular position.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to modification processing (secondary processing) of rotationally symmetrical free-form surfaces, such as optical lenses and molds that require particularly accurate shapes and mirror-finished surfaces. The polishing machine used (two types).

[Prior art]

Traditionally, machining of high-precision free-form surfaces such as optical lenses has mostly been done manually, and a rod-shaped tool is pressed down with manual pressure to determine the removal position and removal method. There was a drawback that it was unstable and a highly accurate curved surface could not be obtained.Also, there is a method disclosed in Japanese Patent Application Laid-Open No. 58-22650, but with this method, the rotation speed of the tool is unstable. In addition, large machined surfaces (2) Fine protrusions remain between the trajectory of the path of the abrasive tool, resulting in insufficient mirror finish. [Objective of the Invention] The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to obtain an accurate and smooth removed shape of the entire workpiece. To provide a curved surface polishing machine that can be used (there are two types).

[Structure of the invention]

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

Fig. 1 is a schematic diagram showing the configuration of a curved surface polishing machine that is an embodiment of the present invention, in which 1 and 2 are rails for pressurizing the tool against the workpiece (2), and 6 is a rotating shaft for tilting the tool. The inclination angle is 5
The range is from 20° to 90°, preferably from 20° to 45°. 5 is a workpiece, and the workpiece holder C1 of 6 is attached and supported by a bearing 18 (2). A polishing liquid holding complement 10 containing liquid 4 can be attached. 7 is a motor for rotating the workpiece.
The rotation speed ranges from 0 r, p, m to 20 or, p, m, but preferably around 100 r, p, m. 8 is the approximate spherical center position of the curved surface shape of the workpiece, and the installation position of the workpiece 5 (the radius of curvature can be changed from 2). 9 is the workpiece inclination angle detection device, which is a photoelectric sensor (from 2, the rotation of the workpiece can be changed). An example of the inclination angle detection device used in this polishing machine is shown in FIG. To accurately calculate the point of contact with Therefore, it can be replaced. 12 is a tool rotation shaft supported by a bearing 17. 14 is a tool drive motor whose rotation speed is set in the range of 10 r, p, m to 200 r, p, m. However, 50 r, p, m, to 100
It is desirable to rotate by r, p, m. 15 is a workpiece support body, and 16 is a drive device such as a pulse motor capable of angular positioning that gives a swinging motion to the workpiece.

〔Example〕

Next, we will explain how to process a convex-shaped workpiece using this polishing machine (two methods will be explained below).

A workpiece 5 whose shape is known in advance is set in this polishing machine, and the workpiece inclination angle detection device 9 detects the angular position to be removed up to an angle corrected in consideration of the radius of curvature of the tip tool 11. The workpiece is rotated by the workpiece rotation drive motor No. 7. Once the angle is determined, the tool shaft is pressed with constant pressure, and both the tool and workpiece are polished for a predetermined time while rotating forcibly.

At this time, in order to obtain a smooth removed shape (2. The workpiece is rotated at a constant swing angle by the action of the pulse motor 16 around the approximate central axis 8 of the curved surface shape. The swing angle is ± The range is from 2 to 20, but preferably from ±5 to ±10.Once the removal process is completed at a determined angular position, it is possible to proceed to the removal process at another angular position.

In the above description, a rotational oscillation is applied to the workpiece side, but similar results can be obtained even if a oscillation movement is applied to the tool shaft 12 side. Alternatively, the polishing liquid holding complement 10 may be removed and the polishing liquid may be circulated through a bonder from another tank and flowed out during processing.

FIG. 2 shows another embodiment for polishing a concave-shaped workpiece.

〔Effect of the invention〕

As explained above, the tool shaft to which the tool with the spherical tip is attached is forcibly rotated to provide the workpiece (two-angle detection function and swing motion). Since it is possible to obtain a smooth shape after removal at a stable removal speed, it is possible to provide a curved surface polishing machine that can obtain a predetermined curved surface shape in a short period of time.

[Brief explanation of the drawing]

FIG. 1 is a front view showing correction polishing of a curved surface of a convex workpiece using a polishing machine according to the present invention;
FIG. 6 shows an example of a photoelectric angle detection device using this c1. FIG. 2 is a front view of a polishing machine for processing a concave workpiece. DESCRIPTION OF SYMBOLS 1...Slide rail [vertical direction], 2...-slide rail (horizontal direction), 6...Rotary axis for tool inclination, 4...polishing liquid, 5...workpiece, 6
. . . Workpiece holder, 7. Workpiece rotation drive motor, 8. Approximation center of the curved surface shape of the workpiece, 9. Workpiece inclination angle detection device, 10. Polishing liquid holding complement. , 11... tip tool,
12... Tool rotation axis, 13... Tool mounting screw,
14... Tool rotation drive motor, 15... Workpiece support, 16... Pulse motor-117... Bearing (workpiece side), 18... Bearing (tool side) 20... Increase Speed gear, 21...Photoelectric film/
Receiver, 22... Power source, 23... Detection slit frame, 24... Display board Figure 1, Section 2, Figure 3

Claims (2)

[Claims] (1) A polishing machine that performs pressure removal processing by rotating a spherical polishing tool has a mechanism that tilts the tool rotation axis with respect to the workpiece, and the workpiece can be moved to any position around the predetermined rotation axis. 1. A curved surface polishing machine, comprising angle detection means for positioning the workpiece, and means for rotating and swinging the workpiece around a rotation axis of the workpiece. (2) The curved surface polishing machine according to claim 1, further comprising a complement capable of submerging the workpiece in a polishing liquid.