JPH04111767A - Lens polishing device - Google Patents

Abstract

PURPOSE:To smoothly perform polishing work of good accuracy by swivelably supporting a point end side holding part to a base end side holding part through an elastic member. CONSTITUTION:In the case that both a holder D and a workpiece lens 2 are difficult to mechanically agree by providing an error between the center of curvature of a polishing spherical surface 24 of a spherical surface polishing tool E and the center of curvature of a polished surface 2c of the workpiece lens 2 sucked to the holder D in a natural condition, a point end side holding part 3 for holding the workpiece lens 2 is swiveled relating to a base end side holding part 7, supported to a fixed supporting shaft 5, by utilizing elastic deformation of an elastic member 17 interposed between both the holding parts 3, 7. In this way, the center of curvature of the polished surface 2c is made possible to agree with the center of curvature of the polishing spherical surface 24 without pressing in the workpiece lens 2 into an annular fitting part 12 while compression-deforming the elastic member 17. Consequently, even in the case of a thin peripheral end part of the workpiece lens 2, a situation, such that the annular fitting part 12 is brought into contact with the polishing surface 24 of the spherical surface polishing tool E, can be avoided.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a lens polishing device.

(Prior Art) As shown in No. 3M, a conventional lens polishing device includes a spherical processing tool A that rotates around an axis passing through the center of curvature of a polished spherical surface a, and a spherical processing tool A that is arranged on an axis passing through the center of curvature. When the holder B has a fixed support shaft, the holder B is rotatably supported by the fixed support shaft and is fitted onto the outer peripheral end C of the lens C to be polished to restrain and support the lens C to be polished. A lens holding part e equipped with an annular fitting part d, and a lens to be polished C.
The holder B has a suction hole f for suctioning the lens, and is configured to polish the lens by swinging the holder B around the center of curvature as the center of swing.

The spherical processing tool A used is one in which the polished spherical surface a has the same radius of curvature as the polished surface g of the lens C to be polished. As shown in FIG. 4, there is an error between the center of curvature OA of the polished spherical surface a and the center of curvature Oc of the polished surface g of the lens C to be polished, which is naturally attracted to the holder B. If it is difficult to match mechanically, the portion of the outer peripheral end C of the lens C to be polished that is brought into pressure contact with the polishing spherical surface a compresses and deforms the elastic member elastically and presses the annular fitting portion. By being pushed into d, the two are brought into alignment.

(Problem to be Solved by the Invention) However, in the above conventional example, when the outer peripheral end of the lens to be polished is thin, when the outer peripheral end is pushed in while compressing and deforming the elastic member, the annular fitting part is processed into a spherical shape. Since it is easy to contact the polished spherical surface of the tool, there is a problem in that the spherical processing tool is easily destroyed by the annular fitting portion.

Furthermore, in the conventional example described above, since the holder is formed in the cross-sectional shape shown in FIG. 3, there is a risk of polishing the front and back sides of the lens to be polished by mistake, which not only damages the lens to be polished and increases material costs. , a part of the lens to be polished will be intensively polished, and a strong force will act on the spherical processing tool, potentially damaging it.

The first invention of the present application is such that even if the outer peripheral edge of the lens to be polished is thin, the center of swing of the polishing surface of the lens to be polished is always aligned with the center of curvature of the machining curved surface of the spherical machining tool without damaging the spherical machining tool. It is an object of the present invention to provide a lens polishing device that can perform polishing processing in a consistent manner.

A second aspect of the present invention aims to provide a lens polishing device that can prevent a holder from accidentally suctioning the front and back sides of a lens to be polished.

(Means for Solving the Problem) In order to achieve the above object, the first invention includes a spherical processing tool that rotates around an axis passing through the center of curvature of a polished spherical surface, and a tool disposed on the axis passing through the center of curvature. The holder includes a fixed support shaft, and an annular fitting portion that is rotatably supported by the fixed support shaft and that fits around the outer peripheral end of the lens to be polished to restrain and support the lens to be polished. A lens polishing device that has a lens holding part and a suction means for suctioning a lens to be polished, and performs lens polishing by relatively rocking a spherical processing tool and a holder about the center of curvature as a rocking center, The lens holding section is composed of a distal side holding section provided with an annular fitting part and a proximal side holding section that is restrained and supported so that its axis always coincides with a fixed support shaft, and the distal side holding section is configured to be connected to the distal side holding section. It is characterized in that the proximal end holding portion is swingably supported via an elastic member. In addition, if the elastic member is not in constant elastic contact with the distal side holding part and the proximal side holding part and the two tend to shift from each other in the radial direction, one of the opposing parts of the distal side holding part and the proximal holding part A step portion around which a ring-shaped elastic member is wound is formed on one side, and a fitting groove into which the elastic member is fitted is formed on the other side to prevent relative movement in the radial direction between the distal side holding portion and the proximal side holding portion. It is preferable to constrain the .

In order to achieve the above object, the second invention includes a spherical processing tool that rotates around an axis passing through the center of curvature of a polished spherical surface, and a lens to be polished that is arranged on the axis passing through the center of curvature and rotatably holds the lens. The holter has an annular fitting part that fits around the outer peripheral end of the lens to be polished to restrain and support the lens to be polished, and an open end in the annular fitting part to vacuum the lens to be polished. the spherical processing tool and the holder are relatively oscillated about the center of curvature as a center of oscillation, and the radius of curvature on the polished surface side is smaller than the radius of curvature on the non-polished surface side. In a lens polishing device that polishes a lens to be polished, when the lens to be polished is attracted to a holder with the non-polished surface side placed on the spherical processing tool side, the lens to be polished comes into contact with the polished surface of the lens to be polished. The lens holding part of the holder is provided with a position regulating part that forms a gap between the outer peripheral end of the lens and the annular fitting part.

(For 1) According to the first invention, there is an error between the center of curvature of the polished spherical surface and the center of curvature of the polished surface of the lens to be polished, which is naturally attracted to the holder, and the two are mechanically matched. If this is difficult, the distal end holding section that holds the lens to be polished can be swung against the proximal end holding section supported by the fixed support shaft using elastic deformation of an elastic member interposed between the two. By doing so, the center of curvature of the polished surface can be made to coincide with the center of curvature of the polished spherical surface, without the lens to be polished being forced into the annular fitting part while compressing and deforming the elastic member as in the conventional example. Therefore, even if the outer circumferential end of the lens to be polished is thin, it is possible to avoid a situation in which the annular fitting portion comes into contact with the polished spherical surface of the spherical processing tool.

According to the second invention, when polishing a convex lens to be polished in which the radius of curvature on the polishing surface side is smaller than the radius of curvature on the non-polishing surface side, the polishing surface is accidentally pushed toward the holder and the lens to be polished is sucked. In this case, the position regulating part comes into contact with the polishing surface and forms a gap between the outer peripheral end of the lens to be polished and the annular fitting part, indicating that the front and back sides of the lens to be polished are incorrectly attracted. Therefore, it is possible to avoid a situation where the holder accidentally attracts the polished surface of the lens to be polished.

(Example) An embodiment of the present invention will be described based on FIGS. 1 and 2.

The holder D of the lens polishing apparatus in this embodiment will be explained. In the lens holding part 1, a distal end holding part 3 for suctioning and holding the lens 2 to be polished is attached to the lower end of a fixed support shaft 5 having an intake/exhaust hole 4 in the axial center through a ball bearing 6 around the axis. The proximal end holding portion 7 is rotatably disposed on the proximal end side holding portion 7. The inner ring portion of the ball bearing 6 is fixed to the outer peripheral portion of the fixed support shaft 5 by a nut 8. The outer ring portion of the ball bearing 6 is fixed to the inner peripheral portion of the proximal holding portion 7 by a bearing holder 9.

The distal end holding portion 3 includes a cylindrical portion 10 that is loosely inserted into the intake/exhaust hole 4 . This cylindrical portion 1O has a communication hole (adsorption means) 11 in the vertical direction communicating with the intake/exhaust hole 4, and its lower end is opened at the center of the lower end of the tip-side holding portion 3. The holder D of this embodiment has a lens holding part 1 consisting of this communicating hole 11, a distal end holding part 3, and a proximal holding part 7.
and a fixed support shaft 5 that rotatably supports this lens holding portion 1.

The lens to be polished 2
An annular fitting portion 12 is provided which abuts against the outer peripheral end portion 2a of the lens 2 to restrain and support the lens 2 to be polished. In this embodiment, the receiving part 13 formed on the inner circumferential side of the annular fitting part 12 is configured to inelastically abut against the outer circumferential end 2a of the lens to be polished 2 on the non-polished surface 2b side. There is. Said annular fitting part 1
The vertical dimension of the portion where the inner circumferential surface of lens 2 contacts the outer circumferential end 2a of the lens to be polished 2 is smaller than the thickness dimension of the outer circumferential end 2a. Note that the lens to be polished 2 in this embodiment has a polished surface 2c.
has a convex shape with a radius of curvature larger than the radius of curvature of the non-polished surface 2b.
When the polishing surface 2c is mistakenly attracted to the distal end holding portion 3, a position regulating portion 14 contacts the polishing surface 2C to form a gap between the lens to be polished 2 and the annular fitting portion 12. are arranged radially in a raised manner.

In this tip side holding part 3, a nand 15 screwed into a male screw part formed on the outer peripheral surface of a large diameter part located on the proximal end side of the cylinder part 10 is attached to a lower end part of the inner periphery of the hair ring presser 9. By being supported by the formed step portion 16, it is swingably supported by the proximal end holding portion 7. Further, a ring-shaped elastic member 17 is disposed between the distal end side holding portion 3 and the bearing holder 9, and the elastic member 17 is configured to be compressed into a rhombus shape during the swinging. The arrangement state of the elastic member 17 will be explained in detail based on FIG. It is wrapped around the side part. The cross-sectional shape of this elastic member [7] is a shape, and the lower end portion is in elastic contact with the fitting groove 19 having a V-shaped cross section and formed in an annular shape on the upper surface of the annular fitting portion 12. It is embedded in Thereby, it is possible to prevent the distal side holding part 3 from being eccentric in the radial direction from the rotation axis of the proximal side holding part 7 during rocking.

The communication hole 11 of the distal end holding portion 3 is connected to the three-way switching valve 20 through the intake/exhaust hole 4, as shown in FIG. This three-way switching valve 20 is connected to a vacuum pump 21 and a compressed air source 22, respectively.

A pressure sensor 23 is disposed in the communication path between the three-way switching valve 20 and the vacuum pump 21 to check for erroneous suction of the lens 2 to be polished depending on the pressure in the communication path.

On the other hand, the spherical surface processing tool E for polishing the polished surface 2C of the lens to be polished 2 includes a polished spherical surface 24 having the same radius of curvature as the polished surface 2C, and the center of curvature of the polished spherical surface 24 is 0. It is configured to be rotatable by a driving means (not shown) around an axis passing through the . On the other hand, the curvature center of the holder D is ○.

It is configured so that it can be swung by a drive means (not shown) about the swiveling center.

In the above configuration, the lens to be polished 2 is
b towards the distal end side holding part 3 of the holder D and the annular fitting part 1.
2, and the three-way switching valve 2 is inserted into the three-way switching valve 2 with the outer peripheral end 2a of the lens to be polished 2 in contact with the inner peripheral surface of the annular fitting part 12.
0 to the vacuum pump 21 side and operate the vacuum pump 21, the non-polished surface 2b is moved to the tip side holding portion 3.
The lens to be polished 2 can be held by being attracted to the lens. In this suction state, the polished surface 2c of the lens to be polished 2 is brought into pressure contact with the polished spherical surface 24 of the spherical processing tool E, and the spherical processing tool E
is rotated around its axis to cause the lens to be polished 2 to rotate together with the distal end holding part 5 and the proximal holding part 7, and the holder D is rocked about the center of curvature OE of the polished spherical surface 24. make it move.

At this time, if the center of curvature of the polished surface 2c of the lens to be polished 2 is shifted from the center of oscillation, a gap will be unevenly formed between the polished surface 2c and the polished spherical surface 24. In this case, the portion of the lens to be polished 2 that is in pressure contact with the polishing spherical surface 24 pushes the tip-side holding portion 3, and the corresponding portion of the elastic member 17 is compressed and deformed, thereby moving the tip-side holding portion 3 to the polishing surface. 2
C is swung in a direction in which the polishing spherical surface 24 is brought into close contact with the entire surface. Thereby, the center of curvature of the polishing surface 2C can be made to coincide with the center of curvature OE of the polishing spherical surface 24, so that the polishing surface 2
c can be polished with high precision. After the polishing work is completed, the three-way switching valve 20 is switched to the compressed air source 22 side, and the compressed air #22 is activated to release the vacuum state in the communication hole 11 of the tip side holding part 3, thereby removing the lens 2 to be polished. can be removed from holder D.

If you accidentally place the polished surface 2C of the lens 2 to be polished on the holder D.
If the non-polished surface 2b is polished by adsorption to
b is brought into pressure contact with the polishing spherical surface 24, so that only the outer peripheral end of the non-polishing surface 2b is locally pressed against the polishing spherical surface 24 and polished. If this happens, the curved shape of the non-polished surface 2b will change and the polished lens 2 will be damaged, which not only increases the material cost, but also, if the outer peripheral end 2a is thin, the outer peripheral end 2a will be intensively polished. As a result, the corresponding portion of the annular fitting portion 12 of the distal end holding portion 3 comes into contact with the polishing spherical surface 24, and there is a risk that the spherical processing tool E may be damaged.

In response to this, as shown in FIG. 2, the regulating part 14 of the distal end holding part 3 of the holder D comes into contact with the polishing surface 2c, creating a gap between the lens to be polished 2 and the annular fitting part 12. By forming this, outside air can flow into the communication hole 11 of the lens holding part l, so the pressure inside the communication hole 11 communicating with the vacuum pump 21 can be measured by the pressure sensor 23 to prevent errors in polishing the lens 2. You can learn about adsorption. Then, the three-way switching valve 20 is switched to the compressed air source 22 side, and the compressed air source 22 is operated to return the inside of the communication hole 11 of the lens holding part 1 to atmospheric pressure, thereby canceling the adsorption operation on the lens to be polished 2. This makes it possible to prevent the lens 2 to be polished from being attracted to the wrong surface.

(Effects of the Invention) Since the first invention of the present application has the above configuration and operation, even if the outer peripheral edge of the lens to be polished is thin, the center of curvature of the polished surface of the lens to be polished can be changed to a spherical surface without damaging the spherical processing tool. The center of curvature of the tJD machining surface of the machining tool can be made to coincide with the center of curvature, and the polishing process can be performed smoothly and with good sensitivity.

Since the second invention of the present application has the above-described structure and operation, it is possible to prevent the lens to be polished from being adsorbed to the holder and polished with the wrong front and back sides, and to prevent loss of the lens to be polished and damage to the spherical processing tool. This can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a diagram showing its main parts and a schematic configuration of the suction drive means, FIG. 3 is a longitudinal sectional view of a conventional example, and FIG. 4 is its operation. It is an explanatory diagram. Lens holding part polished lens ah C t-- 14--... 19--1 -... 24--... D--...---... E--1-... Outer periphery end non-polished Polished surface Tip side holding part Fixed support shaft Proximal side holding part Adsorption means Annular fitting part...Position regulating part Elastic member Step part Fitting groove Polishing spherical surface holder Spherical processing tool

Claims (3)

[Claims] (1) A spherical processing tool that rotates around an axis passing through the center of curvature of a polished spherical surface, and a holder disposed on the axis passing through the center of curvature, the holder having a fixed support shaft and a fixed support shaft attached to the fixed support shaft. It has a lens holding part that is rotatably supported and has an annular fitting part that fits around the outer peripheral end of the lens to be polished to restrain and support the lens to be polished, and a suction means that attracts the lens to be polished. and a lens polishing device that performs lens polishing by relatively rocking a spherical processing tool and a holder about the center of curvature as a rocking center, wherein the lens holding portion is a distal end holding portion having an annular fitting portion. , and a proximal side holding part that is restrained and supported so that the axis always coincides with the fixed support shaft, and the distal side holding part is swingably supported by the proximal side holding part via an elastic member. A lens polishing device characterized by: (2) Forming a stepped part around which a ring-shaped elastic member is wound on one of the facing parts of the distal side holding part and the proximal holding part, and forming a fitting groove into which the elastic member is fitted on the other side. 2. The lens polishing device according to claim 1, wherein relative movement in the radial direction between the distal end holding portion and the proximal holding portion is restrained. (3) comprising a spherical processing tool that rotates around an axis passing through the center of curvature of the polished spherical surface, and a holder disposed on the axis passing through the center of curvature and rotatably holding the lens to be polished;
The holder includes an annular fitting part that fits over the outer peripheral end of the lens to be polished to restrain and support the lens to be polished, and a vacuum suction means that has an open end inside the annular fitting part and vacuum suctions the lens to be polished. and relatively swing the spherical processing tool and the holder about the center of curvature as the center of swing, to produce a convex polished lens in which the radius of curvature on the polished surface side is smaller than the radius of curvature on the non-polished surface side. In a lens polishing device for polishing, when a lens to be polished is attracted to a holder with the non-polished surface side disposed on the spherical processing tool side, the lens comes into contact with the polished surface of the lens to be polished, and the outer peripheral edge of the lens to be polished and the A lens polishing device characterized in that a position regulating part is provided in a lens holding part of a holder to form a gap between it and the annular fitting part.