JP3088865B2 - Ophthalmic lens material holding device and cutting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmic lens material holding apparatus and a cutting apparatus to which the apparatus is applied. More specifically, in a process of manufacturing an ophthalmic lens such as a contact lens and an intraocular lens, holding for fixing the lens material to a cutting device for cutting an ophthalmic lens material (hereinafter, simply referred to as a lens material). The present invention relates to a device and a cutting device.

[0002]

2. Description of the Related Art Conventionally, a draw bar type chuck and a vacuum type chuck have been known as chucks for fixing a lens material to a cutting device.

As shown in FIG. 6, a draw bar type chuck 51 comprises a collet chuck 52 and a bottomed cylindrical holder 53 for holding the collet chuck 52 so as to wrap it. A hollow main shaft 54 for transmitting a rotational force from A1 to the holder 53
Are connected. A bar-shaped draw bar 55 for transmitting reciprocating power from the reciprocating drive unit R to the collet chuck 52 is connected to the base of the collet chuck 52.

A draw bar 55 is inserted so that a slight clearance is formed in the hollow portion of the main shaft 54, and is inserted through a hole 53a at the bottom of the holder 53. A collet chuck 52 holds a lens material. A plurality of claws 52a are formed. The back surface of the claw 52a is tapered, that is, the outer diameter is gradually reduced from the claw 52a of the collet chuck 52 to the base, and the collet chuck 52 is pulled by the reciprocating drive unit R via the draw bar 55, so that the claw is formed. 52a is pressed against the opening edge of the holder 53, so that the plurality of claws 5
2a closes each other, and the lens material L inside is gripped.
Conversely, when the collet chuck 52 is pushed out of the holder 53, the claw 52a returns to its original open state, and the lens material L inside comes off.

Next, the vacuum type chuck 61 will be described with reference to FIG. The vacuum type chuck 61 has a cylindrical shape in which a gas passage 62 is formed along a central axis. The chuck 61 is provided with the chuck 6 from the rotation drive unit A2.
One end of a main shaft 63 for transmitting a rotational force to the shaft 1 is connected to the shaft 1. A gas passage 64 communicating with the gas passage 62 of the chuck 61 is formed in the main shaft 63 along the central axis. On the other end side of the main shaft 63, an air suction device V communicating with the gas passage 64 is provided.

Accordingly, the lens material L is disposed at the end of the chuck 61 to close the gas passage 62, and the air suction device V
Is operated, the inside of the gas passage 62 becomes negative pressure, and the lens material L is fixed by being sucked into the end of the chuck 61.

[0007]

In the case of the draw bar type chuck, as shown in FIG. 8, the nail of the chuck holds the ophthalmic lens material L firmly from the outer periphery.
Depending on the type of lens material, the material may be distorted, and the curved surface R may be deformed when the lens material is released, making it very difficult to cut into a desired shape.

Further, in the case of a vacuum type chuck, an extremely large suction device is required in consideration of the cutting resistance when cutting, and the finished surface of the suction surface of the held lens material must be made extremely smooth. As a result, there is a problem that the manufacturing cost or the equipment cost becomes extremely high.

[0009] Further, in the case of holding the lens material by suction, there is a problem that it is difficult to align the center with the main axis (center) of the holding body.

Furthermore, in recent years, in order to reduce the manufacturing cost, it has been considered to reduce the cutting time by rotating the lens material held by the holding body at a high speed (about 15,000 rpm). In such a case, since the lens material L must be held with a stronger force, the above-mentioned problem has come to be taken up greatly.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem. A suction holding means for sucking and holding a substantially central portion of a lens material is provided inside a chuck for holding the lens material from the outer periphery. In addition, the deformation of the lens material due to the gripping force of the chuck is extremely small, and the centering can be easily performed.
It is another object of the present invention to provide an ophthalmic lens material holding device and a cutting device that require less manufacturing and equipment costs.

[0012]

An ophthalmic lens material holding apparatus according to the present invention comprises a chuck for gripping the outer periphery of the ophthalmic lens material and a suction holding means for sucking a substantially central portion of the ophthalmic lens material. Do Ri, front Symbol suction holding means, said chucking
A gas passage is provided inside the gasket, and the gas passage is connected to a gas supply source.
A device for holding an ophthalmic lens material, comprising : (a) the chuck has elasticity and is slightly opened;
Collet chisel with a plurality of nails at the tip
And an opening diameter regulating portion for regulating the opening diameter of the claw.
An outer cylindrical portion having a substantially cylindrical shape having an end,
Pull the collet chuck from the tip to the inside
Consists of a biasing to have a spring member, (b) the suction holding means, said collet chuck
It has a gas passage inside and has a gas passage at the tip.
A suction tube having a pore communicating with a passage, and a gas supply source.
Advanced in the direction to close the gas passage by air supply, and
Backward in the direction to open the gas passage due to the negative pressure from the gas supply
A retracting valve, and the collet tube within the outer cylinder portion.
Slidably fitted between the jack and the valve
Consists of a ring, (c) opening and closing of the chuck, the suction-holding means
It is configured to be performed by moving the provided valve.
Is characterized in Rukoto that form.

[0013]

[0014]

Further, the apparatus for cutting ophthalmic lens material according to the present invention comprises a holding body for holding the ophthalmic lens material, and a cutting body for cutting the held ophthalmic lens material with a cutting tool. A cutting device, wherein the holding device is mounted on the holding body.

[0016]

According to the ophthalmic lens material holding device and the cutting device of the present invention, the ophthalmic lens material is held by both the gripping force of the chuck and the suction force of the suction holding means. Deformation of the lens material due to force can be minimized, and centering can be easily performed with a simple device. In addition, cutting can be performed at high speed, reducing cutting time,
Manufacturing costs can also be reduced. Further, the cha
The opening and closing of the hook is performed by the cover provided in the suction holding means.
This is done by moving the lube back and forth,
Therefore, the gripping operation by the chuck and the suction holding means
Control of the suction operation by one supply source.
Wear. For this reason, the device can be made compact.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an ophthalmic lens material holding device and a cutting device according to the present invention.

FIG. 1 is a cutaway perspective view showing an embodiment of the holding device of the present invention, FIG. 2 is a cross-sectional view showing the holding state of the holding device of FIG. 1, and FIG. 3 is an open state of the holding device of FIG. Sectional view,
FIG. 4 is a cutaway perspective view showing a reference example of the holding device of the present invention, and FIG. 5 is an explanatory diagram of a cutting device to which the holding device of the present invention is applied.

First, a cutting device to which the holding device of the present invention is applied will be described with reference to FIG. The cutting device is a base 4
1. It comprises a cutting body 42 and a holding body 43, and the cutting body 42 and the holding body 43 are installed on the base 41,
The lens material L is held on the holding body 43 side, and the cutting body 4 is held.
The lens material L is cut using a cutting tool 44 attached to the second side. In the present embodiment, as indicated by the arrow, the movement of the holding body 43 is
5, the cutting body 42 is configured to make a forward and backward movement in a direction approaching or moving away from the lens material L, and also to be able to perform a turning movement. The holding device 46 of the present invention is installed at the tip of the holding main body 43 so that the center is aligned with the main shaft 45. Also, in FIG.
Although the three sides are configured to rotate with respect to the main shaft 45, a rotating cutting tool such as a mill may be used on the cutting body 42 side.

Next, the holding device of the present invention will be described with reference to FIG. The chuck 1 that grips the lens material L from the outer periphery includes an outer cylinder part 3, a collet chuck 2 provided inside the outer cylinder part 3, and a spring member 11 for urging the collet chuck 2 in a closing direction. The suction holding means 4 for adsorbing the substantially central portion of the lens material L includes a pore 5 formed on the adsorption surface of the lens material L and a gas passage 6 communicating with a gas supply source 22.
And a suction pipe 7 having the pores 5 and the gas passage 6
And a valve 9 for opening and closing the gas passage 6 and an air chamber 10 for moving the valve 9 forward and backward by a change in pressure. A ring 8 is interposed between the collet chuck 2 and the valve 9, and the collet is moved by the advance of the valve 9. The chuck 2 is configured to open.

Therefore, first, each part constituting the chuck 1 will be described. The collet chuck 2 has a substantially cylindrical shape, and four elastic claws 2a for gripping the lens material L are radially formed at the distal end thereof. The inner edge of the claw 2a has a cylindrical gripping surface 2c when closed to hold the lens material L from the outer periphery. The back surface of the claw 2a is conical, that is, from the vicinity of the tip of the claw 2a to the root. Tapered surface 2b whose outer diameter gradually decreases
And is regulated by the inner edge of the opening diameter regulating portion 3a at the tip of the outer cylindrical portion 3. That is, when the collet chuck 2 retreats with respect to the outer cylindrical portion 3, the inner edge of the opening diameter regulating portion 3a pushes the tapered surface 2b of the claw 2a to close the four claws 2a in the radial direction. When these four claws 2a are pushed out from the opening diameter regulating portion 3a, they return to the opening direction by the elastic force of the collet chuck 2 itself.

In the body of the collet chuck 2, an inner hole 2 for inserting and holding a suction holding means 4 to be described later is provided.
The collet chuck 2 has a long hole 2d that penetrates the projection 7a of the suction tube 7 inserted into the inner hole 2f. Since the projection 7a is fixed to the outer cylindrical portion 3, the size of the long hole 2d is formed so that the collet chuck 2 can be moved back and forth with respect to the outer cylindrical portion 3 by a distance M required for opening and closing operation. Have been. Further, an annular groove 2e is provided in the rear inside of the collet chuck 2, and a spring member 11 described later is inserted therein. In the illustrated example, the collet chuck 2 having four claws 2a has been described. However, it is needless to say that the collet chuck 2 having two, three or more claws 2a has the same effect as the present embodiment. No.

The outer cylindrical portion 3 has an opening diameter regulating portion 3a at the tip and a hollow portion 3b inside, and has an opening diameter regulating portion 3a.
The collet chuck 2 is inserted into the cavity 3b from above. The base 3 c on the base side of the outer cylinder 3 has a large outer diameter and is bolted to the holding main body 43 of the cutting device via the main body connecting member 19. An air chamber 10 is formed in the hollow portion 3b of the base 3c by the upper surface of the main body connection member 19. Further, it has a recess 3d into which a projection 7a of the suction tube 7 described later is fitted. However, when the holding body 43 rotates, a screw hole for balancing may be formed in the outer peripheral portion of the outer cylindrical portion 3 and a set screw may be screwed into the hole.

The spring member 11 is provided between an outer periphery of a suction pipe 7 described later and an annular groove 2e of the collet chuck 2. Since the suction tube 7 is fixed to the outer cylindrical portion 3 by the protrusion 7a, the spring member 11 urges the collet chuck 2 in the direction of arrow A by pressing the annular protrusion 7b of the suction tube 7. As a result, the collet chuck 2 normally
The closed state is maintained so that the lens material L gripped by a sudden power failure or the like does not drop.

Next, each part constituting the suction holding means 4 will be described. The suction pipe 7 is a tubular body having a fine hole 5 at the tip and a gas passage 6 inside, and is inserted into the collet chuck 2. Projection 7 provided on outer periphery of suction tube 7
a protrudes radially from a long hole 2d formed in the collet chuck 2 and fits into a concave portion 3d inside the outer cylindrical portion 3;
It is fixed to the outer cylinder 3 by a screw 18.

The pore 5 at the tip of the suction tube 7 may be formed by reducing the diameter of the opening at the opening of the suction tube 7, but in this embodiment, a porous member is fitted to the tip of the suction tube 7. The lens material holding member 5a is attached to form a pore 5 in the hole. Alternatively, a suction pipe whose tip is integrally closed by the same member (a kind of bottomed tubular body) may be used to protrude from the closed portion. This lens material holding member 5a
Plays a role of adsorbing the lens material L, and holds the lens material L at a fixed position in the outer cylindrical portion 3 together with the collet chuck, thereby making it possible to manufacture an ophthalmic lens of a desired fixed standard.

An annular projection 7 is provided at the rear base of the projection 7a.
b is provided, abuts against the spring member 11, and urges the collet chuck 2 in the direction of arrow A via the spring member 11. The root of the suction tube 7 is inserted into a ring 8 described later.

The valve 9 has a frusto-conical tip portion 9a, is inserted into the main body connecting member 19 so as to be able to advance and retreat, and closes a connecting hole 8b inside the ring 8, which will be described later.
It is urged by a spring member 12 in the direction of arrow B.

The ring 8 is provided inside the outer cylinder 3 so as to be slidable with respect to the outer cylinder 3. In addition, one end contacts an air chamber 10 provided inside the base 3c side, and the air chamber 10
In order to ensure airtightness, the outer peripheral diameter is substantially equal to the inner diameter of the outer cylindrical portion 3. In the illustrated example, the O-ring 13 is further fitted on the outer periphery of the ring 8 to further improve the airtightness. Further, the amount of movement in the front-rear direction is regulated by the stopper 17, and the tip 8a pushes the end of the collet chuck 2 to push out the collet chuck 2 so that the collet chuck 2 can be opened.

The interior of the ring 8 is configured to communicate with the air chamber 10 near the base of the suction pipe 7 and near the tip 9a of the valve 9, and the tip 9a of the valve is indicated by an arrow B.
The connection hole 8b has a tapered portion corresponding to the inclination of the tip 9a of the valve so that the gas passage 6 in the suction tube 7 is completely closed by being pressed in the direction.

The ring 8 is connected to the suction holding means 4 described above.
In this regard, the advance output of the valve 9 is used as a force for causing the chuck 1 to advance.
Is different from the other embodiments of FIG.

The air chamber 10 is connected to the main body connecting member 19.
An external gas supply source 22 is provided by a gas hole 21 formed in
When the air chamber 10 is evacuated to vacuum, the valve 9
Retreats in the direction opposite to the arrow B against the urging force of the spring member 12, opens the connection hole 8b, evacuates the gas passage 6, and adsorbs the central portion of the lens material L on the surface of the lens material holding member 5a. Can be held. At this time, the collet chuck 2 is in a closed state by the urging force of the spring member 11. Further, when air is supplied from the gas supply source 22, the valve 9 advances in the direction of arrow B, closes the connection hole 8b, and sets the lens material L
Becomes removable. At this time, collet chuck 2
Is pushed out in the direction of arrow B by the valve 9 via the ring 8 and is in an open state.

Next, the operation of the holding device configured as described above will be described. FIG. 2 is a sectional view showing a state where the lens material L is held, and FIG. 3 is a sectional view showing a state where the lens material L is removed or attached.

First, the claws 2a of the collet chuck 2 are closed, and the lens material L is gripped by the gripping surface 2c. Next, as shown in FIG. 2, the lens material L is adsorbed by operating the suction holding means. That is, when the gas in the air chamber 10 is drawn from the gas holes 21 by the gas supply source 22 provided on the holding body 43 side, the air chamber 10 is in a pressure state lower than the atmospheric pressure. When this pressure becomes greater than the urging force of the spring member 12 in the direction of arrow B, the valve 9 retreats in the direction of arrow C, opens the connection hole 8b, and stops in a state where the forces are balanced. Therefore, air is drawn from the gas passage 6 to the gas supply source 22 as shown by the arrow D through the opened connection hole 8b, and the inside of the gas passage 6 becomes a negative pressure, so that the surface of the lens material holding member 5a having the pores 5 is removed. The lens material L is held by suction.

As described above, the lens material L is held by both the holding force of the collet chuck 2 and the suction force of the suction holding means 4. In addition, the setting of the suction force
This is performed by adjusting the vacuum pressure of the gas supply source 22, and the gripping force of the collet chuck 2 can be arbitrarily set by the shape of the chuck, the material, or the urging force of the spring member 11.

Next, when removing the lens material L,
As shown in FIG. 3, air E is sent from the gas supply source 22 into the air chamber 10 through the gas holes 21 to increase the pressure in the air chamber so that the pressure in the gas passage 6 becomes equal to the atmospheric pressure. Then, since the valve 9 is originally urged by the spring member 12 in the direction of arrow B so as to close the connection hole 8b, the connection hole 8b is maintained in the closed state, and the gas passage 6 is maintained at the atmospheric pressure. To do it. In this state,
The lens material L can be released from the suction holding means. However, when the pressure of the air chamber is further increased to push the valve 9 further in the F direction than the steady state of the spring member 12, the tip 9a of the valve 9 Pushes the ring 8 forward. Then, the ring 8 pushes the end of the collet chuck 2 with its tip 8a, and the collet chuck 2
It is pushed in the direction of arrow G against the urging force of the spring member 11. Thus, the claw 2a at the tip of the collet chuck 2 is
The lens material L is released from the regulation by the opening diameter regulating portion 3a at the tip of the outer cylindrical portion 3 and expands in the direction of the arrow H by its own elastic body force, thereby releasing the gripped lens material L. In this case, if the gas passage 6 is closed by the valve 9 while maintaining the negative pressure,
Although it is conceivable that the removal of the lens material L may be hindered, in reality, there is no strict sealing relationship between the lens material L and the suction tube 7 and a slight gap is generated. There is no hindrance to the removal. In addition,
A hole serving as the above-mentioned gap for setting the pressure of the gas passage 6 to the atmospheric pressure may be provided in the gas passage 6 or the like in advance. The ring 8 is connected to the stopper 17
The movement amount is regulated by this, so that the collet chuck 2 is not pushed out more than necessary.

When the lens material L is gripped by the chuck 1, the gas in the air chamber 10 may be drawn from the gas supply source 22. Then, the valve 9 retreats, and the collet chuck 2 and the ring 8 return to the state of FIG.
Grips the lens material L.

As described above, in the present embodiment shown in FIG. 1, the use of the ring 8 allows the single supply source 22 to control the gripping operation by the chuck 1 and the suction operation by the suction holding means 4. This is very preferable because the apparatus can be made compact. However, the present invention is not limited to such an embodiment.

Next, reference examples of the present invention will be described . This holding device is provided with suction holding means in a conventional draw bar type chuck shown in FIG. That is, the pore 31 is provided at the base of the claw 52 a, the gas passage 32 is provided inside the draw bar 55, and the communication hole 57 of the casing 56 is provided.
Through a gas supply source 58. The illustrated state shows a state where the lens material L is held,
When taking out the lens material L, drawer 55 is pointed at arrow K.
If it advances in the direction, the claw 52a expands and the vacuum pressure from the gas supply source 58 is cut, so that it can be easily taken out.

In the holding body 43, the gas passage 6
As means for supplying and sucking the gas to and 32, the same means as the means disclosed in JP-A-4-129607 is employed. That is, if the holding body 43 does not rotate, the passage connecting the gas passages 6 and 32 and the gas supply sources 22 and 58 can be formed in any manner. Includes gas supply sources 22 and 58 fixed outside the holding body 43,
The rotating gas passages 6 and 32 must be connected in an airtight manner, and care must be taken. Therefore, as shown in FIG. 4, for example, the gas hole 34 communicating with the gas passage 32 is once advanced in the radial direction, and the annular groove 35 is covered with the non-rotating casing 56 so as to cover the trajectory drawn while the inlet of the gas hole 34 rotates. The annular groove 35 is provided inside the gas supply source 5.
Connect with 8. In this way, the gas supplied from the gas supply source 58 fills the annular groove 35, passes through the gas hole 34, and is supplied to the gas passage 32. The same applies when vacuum is applied.

In the chuck of the present invention, a metal material such as carbon steel or stainless steel is usually used as a material for the claws of the collet chuck. However, as long as the material has sufficient strength, toughness and durability to grip the lens material, the material is not particularly limited to a metal material.For example, an engineering plastic such as polycarbonate may be used as a material for the nail. Good.

[0042]

According to the holding device and the cutting device of the present invention, since the ophthalmic lens material is held by both the holding force of the chuck and the suction force of the suction holding means, only the holding force of the chuck is used. In this case, the distortion of the lens material can be made very small or completely eliminated. Also,
Centering work, which was difficult only with the suction force of the vacuum type chuck, can now be easily performed, and a high-performance suction force is not required, eliminating the need for a large suction device and greatly reducing equipment and manufacturing costs. can do. Also,
When cutting is performed at high speed, the chuck portion is urged in the direction in which the chuck portion expands by centrifugal force. However, since the lens material is adsorbed by the suction force, it can be stably held. Therefore, the cutting time can be reduced, and the manufacturing cost can be reduced. Further, the opening and closing of the chuck is performed by the suction
The operation is performed by moving the valve provided in the holding means.
The use of a ring allows
Holding operation, and control of the suction operation by the suction holding means,
It can be done from one source. For this reason,
Can be compact.

[Brief description of the drawings]

FIG. 1 is a cutaway perspective view showing one embodiment of a holding device of the present invention.

FIG. 2 is a sectional view showing a holding state of the holding device of the present invention.

FIG. 3 is a sectional view showing an open state of the holding device of the present invention.

FIG. 4 is a cutaway perspective view showing a reference example of the holding device of the present invention.

FIG. 5 is an explanatory view of one embodiment of the cutting device of the present invention.

FIG. 6 is a schematic sectional view showing an example of a conventional holding device.

FIG. 7 is a schematic sectional view showing an example of a conventional holding device.

FIG. 8 is a main part view showing a holding state of a conventional holding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chuck 2 Collet chuck 2a Claw 3 Outer cylinder part 3a Opening diameter regulating part 4 Suction holding means 5 Pores 6 Gas passage 7 Suction pipe 8 Ring 9 Valve 10 Air chamber 11 Spring member 22 Gas supply source 42 Cutting body 43 Holding body 46 Holding device L Lens material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-104502 (JP, A) JP-A-3-52008 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23B 31/00-31/20 B23Q 3/08

Claims (2)

(57) [Claims] 1. A chuck for gripping the outer circumference of the ocular lens material, Ri Do and a suction holding means for adsorbing the substantially central portion of the ocular lens material, front Symbol suction holding means, said chucking
A gas passage is provided inside the gasket, and the gas passage is connected to a gas supply source.
A device for holding an ophthalmic lens material, comprising : (a) the chuck has elasticity and is slightly opened;
Collet chisel with a plurality of nails at the tip
And an opening diameter regulating portion for regulating the opening diameter of the claw.
An outer cylindrical portion having a substantially cylindrical shape having an end,
Pull the collet chuck from the tip to the inside
Consists of a biasing to have a spring member, (b) the suction holding means, said collet chuck
It has a gas passage inside and has a gas passage at the tip.
A suction tube having a pore communicating with a passage, and a gas supply source.
Advanced in the direction to close the gas passage by air supply, and
Backward in the direction to open the gas passage due to the negative pressure from the gas supply
A retracting valve, and the collet tube within the outer cylinder portion.
Slidably fitted between the jack and the valve
Consists of a ring, (c) opening and closing of the chuck, the suction-holding means
It is configured to be performed by moving the provided valve.
An apparatus for holding an ophthalmic lens material, characterized in that it is formed . 2. A cutting device of the ophthalmic lens material comprising a cutting body for cutting the holding body, and retained ocular lens material of the cutting tool to hold the ocular lens material, No placement claim 1 Symbol An ophthalmic lens material cutting device, wherein an ophthalmic lens material holding device is mounted on the holding body.