JP2003025207A - Curved surface creating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cerate a small spherical surface on a work in high precision and machine an axial symmetrical aspherical shape. SOLUTION: This device is furnished with a work holder 2 to be rotationally driven by holding the work 1, a disk-like formed grinding wheel 9 to grind the work 1 in a state where its outer peripheral surface makes contact with a surface of the work 1, a first moving mechanism 3 to move the work holder 2 in parallel with its axis of rotation 2a, a second moving mechanism 11 to move the grinding wheel 9 at a right angle with the axis of rotation 9a, a revolving base 12 on which the grind wheel and the second moving mechanism are mounted, a revolution mechanism 13 to revolve the revolving base 12 around the neighborhood of a contact position of the work 1 and the grinding wheel 9 as its center and a control means 14 to control the first moving mechanism 3, the second moving mechanism 11 and the revolution mechanism 13 so s to constantly make the outer peripheral surface of the grinding wheel 9 contact with a working surface shape of the work to be targeted.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a curved surface generating apparatus for generating a small convex spherical surface or a rotationally symmetric aspherical surface on a work such as an optical element. 2. Description of the Related Art FIGS. 4 and 5 show a conventional curved surface generating apparatus disclosed in Japanese Patent Publication No. 7-35009 for grinding a lens spherical surface. [0003] As shown in FIG. 4, a rotating shaft 5 is provided on a side of the lens holder 52 opposite to a holding portion of the lens 51.
A control motor 55 for moving the lens holder 52 in parallel with 2a is provided. On the other hand, the grindstone 53 for grinding the lens 51 is provided with another control motor 56 for moving the grindstone 53 in a direction perpendicular to the rotation axis 53a. The grindstone 53 and the control motor 56 are mounted on a substantially fan-shaped base 57, and the base 57 is controlled by the control motor 58 so that the rotation center 57 a near the contact position between the lens 51 and the tip of the grindstone 53 is centered. It is freely rotatable. [0004] The control motors 55, 56, 58 are connected to a control device 59, and the control of the control device 59 allows the relative angle and the moving direction of the grindstone 53 to the lens 51 to be freely set. I have. [0005] In order to form a convex spherical surface on the lens 51 by the apparatus having the above structure, as shown in FIG. 5, a grindstone 53 is positioned so as to intersect with the rotation axis 52a of the lens holder 52 as shown. Then, the grindstone 53 is rotated while rotating the lens 51 together with the lens holder 52. As a result, a convex spherical surface 51a is created on the lens 51. In the above-described apparatus, as the radius of curvature of the spherical surface 51a to be created becomes smaller, the outer diameter of the grindstone 53 must be reduced. For example, when creating a convex spherical surface having an outer diameter of 1 mm and a radius of curvature of 1 mm, a grindstone having an outer diameter of about 0.7 mm is required. However, when processing is performed with a grindstone having a small outer diameter in this way, the grindstone is bent during the processing, and thus there is a problem that a desired spherical shape cannot be obtained. Further, since the conventional apparatus does not have a control function for processing into an aspherical shape, there is an inconvenience that a lens cannot be processed into an aspherical shape. The present invention has been made in consideration of the above-mentioned problems of the prior art, and is capable of forming a minute convex spherical surface on a work such as an optical element with high accuracy, and has an axisymmetric aspheric surface. It is an object of the present invention to provide a curved surface creation device capable of processing a shape. In order to achieve the above object, a curved surface generating apparatus according to the first aspect of the present invention is formed into a disk shape with a work holder that holds a work and is driven to rotate. A grindstone that is driven to rotate while the outer peripheral surface thereof is in contact with the surface of the work, grinds the work, a first moving mechanism that moves the work holder in parallel with its rotation axis, and A second moving mechanism for moving at right angles to the axis, a turning base to which the grindstone and the second moving mechanism are attached, and turning for turning the turning base around a contact position between the workpiece and the grindstone. A mechanism and control means for controlling the first moving mechanism, the second moving mechanism, and the rotating mechanism so that the outer peripheral surface of the grindstone always abuts perpendicularly to a target work surface shape. That you have Features. According to the present invention, the outer peripheral surface of the grinding wheel having a disk shape is brought into contact with the workpiece to perform the processing, whereby the bending of the grinding wheel can be reduced even in the processing of the workpiece having the minute convex spherical surface. This enables highly accurate spherical surface generation processing. Further, the control means controls the first and second moving mechanisms and the rotating mechanism so that the outer peripheral surface of the grindstone always abuts on the target processing surface shape of the work vertically. , It is possible to create a target aspherical shape. Embodiments of the present invention will be specifically described below with reference to the drawings. In each embodiment, the same members are denoted by the same reference numerals and correspond to each other. (Embodiment 1) FIGS. 1 and 2 show Embodiment 1 of the present invention. FIG. 1 is a plan view of a curved surface generating apparatus, and FIG. 2 is an enlarged plan view of a machined portion of the apparatus in FIG. It is. 1 and 2, a work holder 2 detachably holds a work 1 such as an optical element having an outer diameter of about 0.1 mm to 10 mm. Work holder 2 is the first
Is supported by the tip of a rotating spindle 4 fixed on a moving table 3a of the moving mechanism, and is rotatable. The first moving mechanism 3 is a mechanism for moving and positioning the work 1 in a direction parallel to the rotation axis 2a of the work holder 2, and includes the above-described movement table 3a which moves along the rotation axis 2a, and an apparatus. Moving table 3a fixed to main body
And a feed screw 3c for transmitting the rotation of the drive motor 3d to the moving table 3a. A pulley 5 is attached to the other end of the rotary spindle 4 on the side opposite to the work holder 2, and a pulley 7 rotates a motor 6 mounted on the moving table 3a.
The power is transmitted to the rotary spindle 4 via the belt 8 and the pulley 5. A grindstone 9 for forming a curved surface on the work 1 is formed in a disk shape, and is attached to the tip of a grindstone spindle 10 with a grindstone surface on the outer periphery. Whetstone 9
Grinds the work 1 in a state where the outer peripheral grindstone surface is in contact with the surface of the work 1. The grinding wheel spindle 10 is rotated at a high speed (from 10,000 rpm) by a driving means (not shown).
70,000 rpm) and is installed on the moving table 11 a of the second moving mechanism 11. The second moving mechanism 11 is a mechanism for moving and positioning the grindstone 9 in a direction perpendicular to the rotating shaft 9a, and includes a moving table 11a that moves in a direction perpendicular to the rotating shaft 9a. , A guide 11b for guiding the movement of the moving table 11a, a driving motor 11d, and a feed screw 11c for transmitting the rotation of the driving motor 11d to the moving table 11a. In this case, the guide 11b is attached to the turning base 12. The turning base 12 has a drive motor 13 as a rotating mechanism fixed to the apparatus main body at a lower portion, and the work 1 and the grindstone 9 are driven by the drive motor 13.
Is rotatable around a contact position of the rotation center 12a as a rotation center 12a (see FIG. 2). The second moving mechanism 11 is a guide 11
Since it is fixed to the turning base 12 via b, it can rotate in accordance with the turning of the turning base 12. The above-described drive motors 3d, 11d, 13
Are connected to the control device 14, and the position and speed of each of the moving tables 3a, 11a and the turning base 12 can be set by the control of the control device 14.
In addition, the control device 14 controls the drive motors 3d, 11d, and 13 so that the outer peripheral surface of the grindstone 9 always abuts on the target workpiece surface shape perpendicularly. In the processing by the curved surface generating apparatus having the above-described configuration, first, the work 1 is held by the work holder 2, and the drive motor 3 d of the first moving mechanism 3 is driven by the control device 14 to move the work 1 to the grindstone 9. To a predetermined position on the side. Next, the work 1 and the grindstone 9 are rotated, and the drive motor 11d of the second moving mechanism 11 is driven to bring the grindstone 9 into contact with the work 1. In the processing by this device, the distance R (see FIG. 2) between the tip of the grindstone 9 and the rotation center 12a of the turning base 12 is the radius of curvature of the spherical surface to be created, and this distance R is equal to the desired radius of curvature. The grindstone 9 is moved to contact the work 1. Next, in a state where the drive motor 3d and the drive motor 11d are stopped, the turning base 12 is rotated at a predetermined speed by a predetermined angle by the drive motor 13 to perform a spherical surface forming process. According to such an embodiment, by performing processing using the disc-shaped grindstone 9, the bending of the grindstone can be reduced even for the work 1 having a small radius of curvature. For this reason, highly accurate spherical surface generation processing becomes possible. In addition, the tip of the grindstone 9 and the rotation center 1 of the turning base 12
Since the distance to 2a is the radius of curvature of the spherical surface created,
By changing the distance, a spherical surface with a wide radius of curvature can be created with one grindstone. (Embodiment 2) FIG. 3 is an enlarged view of a machined portion of a curved surface creating apparatus according to Embodiment 2. In this embodiment, an aspherical shape is created on the work 1. In the present embodiment, the shape of the work holder 2 in the first embodiment is changed, and the outer diameter of a contact portion of the work holder 2 with the work 1 is smaller than the outer diameter of the work 1. ing. In this embodiment, first, in order to machine the work 1 into a predetermined aspherical shape, the control device 14 controls how the grindstone 9 and the work 1 are driven by the respective drive motors 3d, 11d and 13. Calculate what to do and get the data. Next, the work 1 is held by the work holder 2, the work 1 and the grindstone 9 are rotated, and based on the obtained data, each drive motor is controlled by the controller 14 so that the work 1 is processed into a predetermined aspherical shape. 3d, 11d, 13
Activate At this time, the outer peripheral surface of the grindstone 9 is controlled so as to always contact perpendicularly with the target processing surface shape of the work 1. After forming the aspherical surface on the workpiece 1, the drive motor 13 is turned to rotate the rotating shaft 2a of the work holder 2 and the rotating shaft 9a of the grindstone 9 in parallel (shown by a two-dot chain line in FIG. 3). The pivoted base 12 is pivoted to the position shown in FIG. Next, the driving motor 1 of the second moving mechanism 11
1d is driven to bring the grindstone 9 into contact with the work 1 and the drive motor 3d of the first moving mechanism 3 is driven to move the work 1 in parallel with the rotation axis 2a of the work holder 2 so as to move the work 1 outside the work 1. Perform diameter machining. According to such an embodiment, the work 1
An aspherical shape can be created at the same time, and the outer diameter processing can be performed by the same device. According to the first aspect of the present invention, it is possible to form minute convex spheres having various radii of curvature with high accuracy by using a single grindstone, and to form an axisymmetric aspherical shape. Outer diameter processing of the work becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a curved surface creation device according to a first embodiment. FIG. 2 is an enlarged plan view of a processed portion of the curved surface generating device according to the first embodiment. FIG. 3 is an enlarged plan view of a processed portion of the curved surface generating device according to the second embodiment. FIG. 4 is a plan view of a conventional device. FIG. 5 is a cross-sectional view of a conventional device when a convex surface is created. [Description of Signs] 1 work 2 work holder 3 first moving mechanism 3a moving table 3b guide 3c feed screw 3d drive motor 9 grindstone 10 grindstone spindle 11 second moving mechanism 11a moving table 11b guide 11c feed screw 12 turning base 13 Drive motor 14 controller

Claims (1)

Claims: 1. A work holder which holds a work and is driven to rotate, and which is formed into a disk shape, and which is driven to rotate while its outer peripheral surface is in contact with the surface of the work. A grinding wheel that grinds the workpiece, a first moving mechanism that moves the work holder in parallel with the rotation axis thereof, a second movement mechanism that moves the grinding stone at right angles to the rotation axis thereof, the grinding wheel and the second A turning base to which a moving mechanism is attached, a turning mechanism for turning the turning base around a contact position between the work and the grindstone, and an outer peripheral surface of the grindstone with respect to a target work surface shape. A curved surface generating apparatus, comprising: a control means for controlling the first moving mechanism, the second moving mechanism, and the rotating mechanism so as to always contact vertically.