JPH10138110A - Grinding tool for chamfering optical stock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the double grinding, and to improve the efficiency of the chamfering by forming a material capable of being rough-turned into a disk- shaped member, providing a grinding wheel of the sectional shape so as to be female shape relative to the sectional shape of a part to be chamfered in an optical stock, and simultaneously machining the chamfered part of the optical stock. SOLUTION: The sectional shape of a grinding surface 14 of a grinding wheel 10 for chamfering a lens is female to the sectional shape of a part to be chamfered of a lens stock L, and an outer circumferential part of the lens stock L is ground so as to be the sectional shape reverse to that of the grinding surface 14 by turning and abutting the grinding surface 14. The outer circumferential part of the lens stock L is simultaneously chamfered. Because the grinding surface 14 is formed of the grinding material for rough turn, the service life of the grinding surface 14 is long, and the double grinding is also possible, and the chamfering is efficient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding tool for chamfering an optical material, which is used for "chamfering" an optical material made of an optical material such as an optical glass into a predetermined sectional shape in the vicinity of an outer peripheral portion thereof. Things.

[0002]

2. Description of the Related Art Conventionally, in the processing of an optical material, for example, when a lens is manufactured, a material is formed on an optical material made of an optical material including an optical glass such as a crown-based glass and a flint-based glass, and the lens surface is processed. Processing is performed in the order of lens outer diameter processing. The material removing process is a process of roughly forming an optical material for one lens to obtain an optical material to be processed. The lens surface processing is performed in the order of rough processing, smoothing, and polishing (polishing).

[0003] Of these, the first roughing is a process of improving the surface roughness by bringing the dimensions of the optical material from which the material has been removed close to the final value of the lens, and is called a "roughing machine". And the like. Subsequent smoothing processing is a step of making the surface roughness generated by the rough processing finer and adjusting the thickness dimension of the lens within the required accuracy, and is performed by "sanding" or "diamond smoothing". The final polishing is a step of finishing the lens surface into an optical mirror surface and adjusting its size and shape to within final accuracy, and is performed using a water-slurry abrasive or the like.

[0004] The lens outer diameter processing is called "centering",
After the above polishing process is completed, the optical material polished into a lens shape is mounted on a cylindrical grinding machine called `` centering machine '',
Performing `` centering '' to match the center axis of the cylindrical grinding process with the optical axis of the lens in the centering machine, removing unnecessary parts of the outer diameter part of the centered lens with a grindstone etc. This is a process for obtaining a lens having a diameter. Therefore, in the first stage of lens processing, material processing is performed to a large diameter in consideration of a margin for centering in a designed diameter value.

Conventionally, in this centering step, in addition to shaving the outer diameter of the lens into an appropriate shape, “chamfering” and “frontal chamfering” for forming the cross-sectional shape near the lens outer peripheral portion into a predetermined shape are also included. Had been done.

[0006]

However, the above-described conventional chamfering is performed during the centering process, and since these chamfering processes involve a large amount of machining of the surface to be machined, the centering is performed first. After a coarse grinding tool is attached to the machine to perform rough processing, a fine grinding tool is attached to perform high-precision fine processing. Usually, in order to perform such two-stage processing, two types of grinding tools are used for each processing.

[0007] As a grinding tool for chamfering, an "electroplated grindstone" has conventionally been used. Electroplated whetstone is a metal blank material that is cut, turned, etc., and processed into a substantially disc-shaped member with high precision, and then the abrasive grains made of fine diamond powder are applied to the outer periphery of the substantially disc-shaped member. On the side, etc.
This is a grinding tool formed by electrodepositing a uniform thin layer.

However, the electrodeposited grinding wheel has a short product life, and when high-load grinding (hereinafter, referred to as "heavy grinding") is performed, abrasion or the like occurs in a short period of time and must be replaced. Therefore, there is a problem that the efficiency of the chamfering cannot be increased, which hinders a reduction in manufacturing cost.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a grinding tool for chamfering an optical material having a long product life and capable of heavy grinding. It is in.

[0010]

In order to solve the above-mentioned problems, a grinding tool for chamfering an optical material according to the present invention is formed in a substantially disc-shaped member by a grinding material capable of roughly grinding an optical material made of an optical material. The optical material has an abrasive surface having a cross-sectional shape that is in a female relationship to the cross-sectional shape of the portion to be chamfered in the optical material, and the substantially disk-shaped member is mounted on a roughing machine, and the rotating optical material rotates. The optical material is chamfered by being brought into contact with the optical material.

In the above-mentioned grinding tool for chamfering an optical material,
Preferably, while passing through the grinding surface from the back of the grinding surface on the central axis side of the substantially disk-shaped member, the direction of the penetration is set to substantially match the rotation direction of the substantially disk-shaped member. There is provided a plurality of through holes, and a grinding fluid supply means for supplying a grinding fluid to the contact point between the grinding surface and the optical material through the through holes.

In the above-mentioned grinding tool for chamfering an optical material, preferably, the grinding fluid supply means is provided in a conduit for guiding the grinding fluid along a center axis of the substantially disk-shaped member, and in the conduit. And an ejection hole for ejecting the grinding fluid toward an opening of the through-hole on the central axis side of the substantially disk-shaped member.

In the above-mentioned grinding tool for chamfering an optical material, preferably, on the grinding surface, the substantially disk-shaped member extends from the center axis side to the outer edge side and the direction of the extension extends. Are provided with a plurality of groove-shaped recesses set so as to substantially match the rotation direction of the substantially disk-shaped member, and the grinding fluid is supplied.

In the above-mentioned grinding tool for chamfering an optical material, preferably, a substantially annular concave portion for interconnecting the plurality of groove-shaped concave portions is provided on the polishing surface, and the grinding fluid is supplied. .

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the configuration of a lens chamfering grinder as an embodiment of the optical material chamfering grinder according to the present invention, and the positional relationship between the lens material and the lens chamfering grinder at the time of chamfering a lens and the processing method. FIG. The center line A of the lens chamfering grinding tool 10 (described later) shown in FIG.
2 (described later) indicates a side surface, and an upper portion above the center line A2 indicates a cross section. FIG. 2 is a front view showing the configuration of the lens chamfering grinding tool shown in FIG. 1 as viewed from the direction A.

As shown in FIGS. 1 and 2, the grinding tool 10 for chamfering a lens includes an inclined wall portion 11, a disk portion 12, a shaft portion 13, a grinding surface 14, and an inner liquid supply pipe 15. It is configured. The shaft portion 13 is made of metal such as steel, and is formed in a substantially columnar shape. The disk part 12 is made of metal such as steel,
It is formed in a substantially disk shape and is connected so as to be coaxial with the center line A2 of the shaft portion 13. The inclined wall portion 11 is made of a metal such as steel, and is a substantially cylindrical portion. The outer wall surface of the inclined wall portion 11 is a substantially conical surface having a tapered cross section.
The inclined wall portion 11 is connected to the disk portion 12 so as to be coaxial with the center line A2.

The base of the inner wall of the inclined wall 11 is
Is connected to a conical inclined surface 12a having a downward slope toward the center of the disk portion 12, and the inclined surface 12b is connected to a central flat portion 12b of the disk portion 12. The inner wall of the inclined wall portion 11 and the slope 12a and the flat portion 12b of the disk portion 12 form a substantially columnar concave portion 12c at the center of the disk portion 12.

The grinding surface 14 is made of a rough grinding material such as a “metal diamond grinding wheel” formed by sintering metal and diamond, and a first grinding surface 14 a covering the top surface of the inclined wall portion 11. And a second abrasive surface 14b that covers the inclined outer wall surface of the inclined wall portion 11, and a third abrasive surface 14c that covers a flat portion near the outer edge of the disk portion 12, and these abrasive surfaces are It is formed integrally.

As shown in FIG. 2, a plurality of through holes 11a are provided in the inclined wall portion 11 and the second abrasive surface 14b. These through holes 11a penetrate the inclined wall portion 11 and the second abrasive surface 14b from the side (back portion) that is the center side of the disk portion 12, and communicate with the outside. As shown in FIG. 2, the direction of penetration of each through-hole 11a substantially matches the tangential direction of the arc forming the cross section of the inclined wall portion 11.

As shown in FIG. 2, a plurality of segments 14d are provided on the first abrasive surface 14a. These segments 14 d are groove-shaped concave portions having a substantially “U” -shaped cross section, and extend from the center of the disk portion 12 toward the outer edge. As shown in FIG. 2, the direction in which each segment 14 d extends substantially matches the direction in which the disk portion 12 spirals from the center to the outer edge.

As shown in FIG. 2, a plurality of segments 14e are provided on the third abrasive surface 14c.
These segments 14 e are groove-shaped recesses having a substantially “U” -shaped cross section, and extend from the center of the disk portion 12 toward the outer edge. As shown in FIG. 2, the direction in which each segment 14 e extends substantially matches the direction in which the disk portion 12 spirals from the center to the outer edge.

As shown in FIG. 2, on the third abrasive surface 14c, of the two ends of the plurality of segments 14e, a substantially "U" -shape is formed so that the center-side end of the disk portion 12 communicates with each other. A substantially annular concave portion 14f having a cross section or the like is provided.

The inner liquid supply pipe 15 is a pipe disposed along the center line A2 of the grinding tool 10 for chamfering the lens.
The leading end is shifted from the central flat portion 12 b of the disc portion 12 to the concave portion 1.
2c. The end of the protruding portion of the inner liquid supply pipe 15 is closed, and a plurality of nozzles 15 a
Is provided. The nozzle 15a is a minute opening, and the opening is narrowed toward the tip of the opening.

Next, a method of chamfering a lens material using the above-described lens chamfering grinding tool 10 will be described with reference to FIGS.
This will be described with reference to FIG. Unlike the conventional chamfering, the chamfering of the lens using the lens chamfering grinding tool 10 of the present embodiment is performed by a spherical machining machine called “roughing machine”.

In this roughing machine, the center line A2 of the grinding tool 10 for lens chamfering is mounted so as to be coaxial with a rotary drive shaft (not shown) of the roughing machine. After installation
The lens chamfering grinding tool 10 is rotated, for example, in the direction shown in FIG. The rotary drive shaft of the roughing machine can be moved in the front-rear direction (vertical direction in FIG. 1) and the left-right direction while rotating by a grinding shaft drive mechanism (not shown).

On the other hand, the lens material L before the chamfering is held by the lens holder 20. Lens holder 2
0 has a chuck 21, and the chuck 21 has a concave portion 21 a for holding a lens, a concave portion 21 b for engagement, and a locking mechanism 2.
1c is provided. A slot or the like is provided in the locking mechanism 21c. With such a configuration, the locking mechanism 21c of the chuck 21 is moved by a draw bar (not shown).
The outer edge of the lens material L is engaged with the engaging recess 21b by pulling or sandwiching the lens material L, so that the center line of the lens material L can be held coaxial with the center line A1 of the chuck 21. .

The roughing machine is provided with a chuck shaft (not shown) so that the chuck 21 can be mounted so as to share the center line A1. The chuck shaft is movable in the left-right direction in FIG. 1 by a chuck shaft drive mechanism (not shown). The center lines A1 and A2 are set so as to be parallel to each other.

The lens material L to be chamfered includes a first lens surface S1 having a convex spherical shape and a second lens surface S2 having a concave spherical shape.
An outer peripheral surface S3 having a substantially cylindrical side surface; a first chamfered surface S4 having a substantially annular planar shape; and a second chamfered surface S5 having a substantially conical side surface.
And a third annular chamfered surface S6. These outer peripheral surfaces S3 and the chamfered surfaces S4 to S6
And the like are parts that are attached or fitted to a fixture or the like when the completed lens is attached to an imaging device such as a camera.

As shown in FIG. 1, the cross-sectional shape of the grinding surface 14 of the lens chamfering grinding tool 10 has a female type with respect to the cross-sectional shape of the portion of the lens material L to be chamfered. That is, the first grinding surface 14a is the first chamfered surface S
4 and the second grinding surface 14b is the second type.
The female type corresponding to the chamfered surface S5, the third abrasive surface 1
4c is a female type corresponding to the third chamfered surface S6.

Further, an outer liquid supply pipe 30 is disposed in the vicinity of the contact point between the lens material L and the polishing surface 14. From this outer liquid supply pipe 30, the grinding liquid w is jetted toward the contact position. The grinding fluid w is used for lubrication so that an excessive load is not generated when the grinding surface 14 and the lens material L come into contact with each other so that damage is not caused, and the frictional heat generated by the contact between the grinding surface 14 and the lens material L It is a liquid used for the purpose of cooling and the like and for removing shavings generated by grinding, and has an appropriate composition. As described later, the grinding liquid w is also supplied to the inner liquid supply pipe 15.

In the chamfering of the lens material L, first, a chuck shaft (not shown) is rotationally driven to rotate the lens material L in, for example, the direction shown in FIG. Similarly, by rotating and driving a rotary drive shaft (not shown) of the roughing machine, the lens chamfering grinding tool 10 is rotated, for example, in the direction shown in FIG. In this state, the center line A1
By driving the grinding shaft drive mechanism (not shown) while maintaining the parallel relationship between the lens and A2, the lens chamfering grinding tool 10 is moved in the front-rear direction (up and down direction in FIG. 1) to be close to each other. State as shown.

Next, from this state, by driving a chuck shaft driving mechanism (not shown), the lens material L is moved in the left-right direction of FIG. The grinding tool 10 for lens chamfering is approached while rotating.

As described above, in the lens chamfering grinding tool 10 of the present embodiment, the cross-sectional shape of the grinding surface 14 of the lens chamfering grinding tool 10 is smaller than that of the portion of the lens material L to be chamfered by the female mold. Therefore, the outer peripheral portion of the lens material L is ground so as to have the reverse cross-sectional shape of the grinding surface 14 by rotating and contacting the grinding surface 14. Thereby, the outer peripheral portion of the lens material L is chamfered at the same time. Further, since the grinding surface 14 is formed of a grinding material for roughing, the life of the grinding surface is long, heavy grinding is possible, and efficient chamfering is possible.

At this time, the lens material L
Injection of the grinding fluid w is performed toward the contact point between the grinding wheel 14 and the grinding surface 14. The jetted grinding fluid w directly reaches the grinding location and enters the segment 14e from the outer edge of the lens chamfering grinding tool 10. The grinding tool 10 for lens chamfering is used in a state where the disk surface of the disk portion 12 is vertical as shown in FIG. , The grinding fluid w in the segment 14 e flows down from the outer edge of the disk portion 12 toward the center with the rotation of the lens chamfering grinding tool 10. Moving. During this movement, the grinding fluid w is applied to the third grinding surface 14c and the third chamfered surface S6.
Is supplied to the point of contact.

An annular recess 1 is provided at the center of the segment 14e.
4f communicate with each other, the grinding fluid w
4f. Next, the grinding fluid w is applied to the annular recess 14f.
Flows down the slope of the second abrasive surface 14b to reach the grinding location. During this movement, the grinding fluid w is in contact with the second grinding surface 14b and the second grinding surface 14b.
It is supplied to the contact point with the chamfered surface S5.

Further, a segment 14d is provided on the first grinding surface 14a adjacent to the second grinding surface 14b, and the segment 14d is a groove-shaped recess, which is swirled from the outer edge of the disk portion 12 toward the center. As the grinding tool 10 for lens chamfering rotates, the grinding fluid w in the segment 14 d moves so as to flow down from the outer edge of the disk portion 12 toward the center. During this movement, the grinding fluid w
It is supplied to the contact point between the first grinding surface 14a and the first chamfered surface S4.

Further, an inner liquid supply pipe 15 is provided along the center line A2 of the lens chamfering grinding tool 10, and a nozzle 15a is provided at the tip thereof. When the grinding fluid w is sent, the grinding fluid w is ejected from the nozzle 15a toward the slope 12a of the concave portion 12c of the disk portion 12. The injected grinding fluid w rises on the slope 12a due to the centrifugal force accompanying the rotation of the disk part 12,
It moves in the direction of the opening on the central axis side (back side) of the disk portion 12 among the openings of the through hole 11a. The grinding fluid w then passes through the inside of the through hole 11a, reaches the other opening of the through hole 11a, and is supplied to a contact point between the second grinding surface 14b and the second chamfered surface S5.

As described above, in the lens chamfering grinding tool 10 of the present embodiment, the through holes 11a and the segments 14
Since the grinding fluid w is supplied to the grinding location by d, 14e, etc., the above-described lubrication action, cooling action,
Debris discharging action is performed promptly, and grinding is performed smoothly.

In the above embodiment, the lens chamfering grinding tool 10 corresponds to an optical material chamfering grinding tool.
The lens material L before centering corresponds to an optical material. Further, the inner liquid supply pipe 15 and the nozzle 15a correspond to a grinding liquid supply unit. The inner liquid supply pipe 15 corresponds to a pipe, and the nozzle 15a corresponds to an injection hole.
The segments 14d and 14e correspond to the groove-shaped concave portions.

The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and has substantially the same configuration as the technical idea described in the scope of the claims of the present invention. It is included in the technical scope of the invention.

For example, in the above-described embodiment, a spherical lens has been described as an example of the optical material. However, the present invention is not limited to this, and any optical material capable of chamfering the periphery can be used. May be an aspheric lens, other optical materials such as a mirror,
It may be a prism or the like.

Further, in the above-described embodiment, an example has been described in which a portion other than the abrasive surface of the grinding tool for chamfering an optical material is formed of a metal such as steel. However, the present invention is not limited to this. It may be formed of a material such as ceramics.

In the above-described embodiment, an example has been described in which the grinding surface of the grinding tool for chamfering an optical material is formed of a grinding material such as metal diamond which can be roughly slid.
The present invention is not limited to this, and may be any grinding surface that can roughen an optical material made of an optical material, and a grinding surface of another form, for example, a grinding stone made of a stone material It may be used, one using a grindstone made of ceramics, etc., as well as one having a layered abrasive,
It may be formed of a plate material or a solid abrasive material.

Further, in the above-described embodiment, as an example of the grinding surface of the grinding tool for chamfering an optical material, one having two flat grinding surfaces and an inclined grinding surface connecting the two flat grinding surfaces has been described. The invention is not limited to this, and any grinding surface may be used as long as the grinding surface has a female shape with respect to the sectional shape of the portion to be chamfered near the outer peripheral portion of the optical material.

In the above embodiment, the through hole penetrating in a direction substantially coincident with the tangential direction of the arc forming the cross section of the inclined wall portion 11 has been described as an example. Is not limited to this. In general, any type of through hole may be used as long as the direction of penetration is set so as to substantially match the rotational direction of the substantially disk-shaped member. A hole, for example, a through hole penetrating from the center side of the disk portion 12 to the outer edge portion in a direction substantially coinciding with the spiral direction may be used.

Further, in the above-described embodiment, as the groove-shaped concave portion, the segment 1 extending from the center side of the disk portion 12 to the outer edge portion in a direction substantially coinciding with the spiral direction.
4d, 14e, etc., have been described as examples, but the present invention is not limited to this. Generally, any groove-shaped recess set so that the direction of extension substantially matches the rotational direction of the substantially disk-shaped member. Any shape may be used, and a groove-shaped concave portion extending in another extending direction, for example, a groove-shaped concave portion extending in a direction substantially matching a tangential direction of an arc forming the disk portion 12 may be used. Good.

In the above embodiment, the second
Although the example in which the groove-shaped concave portion is not provided on the grinding surface 14b has been described, the present invention is not limited to this.
A groove-shaped recess may also be provided in b.

[0048]

As described above, according to the grinding tool for chamfering an optical material according to the present invention, the optical tool is formed of a grinding material capable of rough rubbing and has a female mold with respect to the cross-sectional shape of the chamfered portion of the optical material. Since it is configured to have a grinding surface having a cross-sectional shape that is related, the chamfered portion of the optical material is processed at the same time. In addition, since the grinding surface is formed of a grinding material for roughing, the life of the grinding surface is long, heavy grinding is possible, efficient chamfering is possible, and reduction in manufacturing cost is achieved. be able to. Also, if the grinding tool for chamfering optical material is provided with through holes and groove-shaped recesses to supply the grinding fluid to the grinding points, the grinding fluid can quickly perform the lubrication, cooling and debris discharging activities. Therefore, the grinding can be performed smoothly.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration of a lens chamfering grinding tool according to an embodiment of the present invention, a positional relationship between a lens material and a lens chamfering grinding tool during a lens chamfering process, and a processing method.

FIG. 2 is a front view showing the configuration of the lens chamfering grinding tool shown in FIG. 1 as viewed from a direction A.

[Explanation of symbols]

 Reference Signs List 10 Grinding tool for lens chamfering 11 Slant wall portion 11a Through hole 12 Disk portion 12a Slope 12b Flat portion 12c Concave portion 13 Shaft portion 14 Grinding surface 14a First grinding surface 14b Second grinding surface 14c Third grinding surface 14d, 14e Segment 14f Ring Concave part 15 Inner liquid supply pipe 15a Nozzle 20 Lens holder 21 Chuck 21a Lens holding concave part 21b Engaging concave part 21c Locking mechanism 30 Outer liquid supply pipe A1, A2 Rotation center line L Lens material before chamfering S1 First lens Surface S2 Second lens surface S3 Outer peripheral surface S4 First chamfered surface S5 Second chamfered surface S6 Third chamfered surface w Grinding fluid

Claims (5)

[Claims] An optical material made of an optical material is formed into a substantially disk-shaped member by a grinding material capable of rough rubbing, and has a female shape with respect to a sectional shape of a portion to be chamfered in the optical material. The chamfering of the optical material, wherein the chamfering of the optical material is performed by attaching the substantially disk-shaped member to a roughing machine and rotating and contacting the rotating optical material. Grinding tools. 2. The grinding tool for chamfering an optical material according to claim 1, wherein the grinding surface penetrates the grinding surface from the back of the grinding surface, which is on the center axis side of the substantially disk-shaped member, and the direction of the penetration is substantially the same. A plurality of through-holes set to substantially match the rotation direction of the disc-shaped member; and a grinding fluid supply means for supplying a grinding fluid to the contact point between the grinding surface and the optical material via the through-hole. A grinding tool for chamfering optical materials. 3. The grinding tool for chamfering an optical material according to claim 2, wherein the grinding fluid supply means is provided in the pipeline for guiding the grinding fluid along a central axis of the substantially disk-shaped member. A grinding tool for chamfering an optical material, characterized in that the grinding tool has a spray hole for spraying the grinding fluid toward an opening of the through-hole on the central axis side of the substantially disk-shaped member. 4. The grinding tool for chamfering an optical material according to any one of claims 1 to 3, wherein: on the grinding surface, from a center axis side of the substantially disk-shaped member to an outer edge side. And a plurality of groove-shaped recesses set so that the direction of the extension substantially matches the rotational direction of the substantially disk-shaped member are provided, and the grinding fluid is supplied. Grinding tool for chamfering optical materials. 5. The grinding tool for chamfering an optical material according to claim 5, wherein a substantially annular concave portion is provided on the polishing surface for interconnecting the plurality of groove-shaped concave portions, and the grinding fluid is supplied. A grinding tool for chamfering optical materials.