JP2002283225A - Machining device and machining method of concave spherical surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly accurately machine a concave spherical surface by preventing dislocation of a spherical tool when machining a workpiece to form the concave spherical surface by the spherical tool. SOLUTION: This machining device forms the concave spherical surface by transferring the spherical tool 2 on the workpiece 1 by allowing the spherical tool 2 vibrating by an ultrasonic wave to abut to the workpiece 1. A movement restricting means 4 is provided for restricting the advancing direction of the spherical tool 2 at machining time by abutting to the spherical tool 2 to machine the concave spherical surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus and a processing method for creating a concave spherical surface.

[0002]

2. Description of the Related Art JP-A-11-333702 discloses that
A conventional apparatus for processing a concave spherical surface on a workpiece such as a lens is described. 14 and 15 show this processing apparatus.

As shown in FIG. 14, the tool shaft 140 on the side to be machined is directed upward, and the workpiece shaft 1 on the side to be machined.
41 is arranged below. The tool shaft 140 is vertically movable along a guide 121 attached to the upper part of the gantry (not shown), and the movement is fixed at a fixed position. Tool shaft 140
Includes an ultrasonic oscillator 101 whose output is controlled by a controller 120, a shaft 102 integrally provided at a lower end of the ultrasonic oscillator 101, and a horn 103 fixed to a lower end of the shaft 102. At the lower end of the horn 103, a spherical tool 104 made of a steel ball is arranged.

The workpiece shaft 141 has a mounting table 106 to which a lens 105 as a workpiece is fixed by bonding, and a cylinder 107 for supporting the mounting table 106. The cylinder 107 presses the mounting table 106 upward in a state where the tool 104 and the lens 105 are in contact with each other, and the tool shaft 140
The load is applied in the direction.

[0005] A micrometer 108 is in contact with the upper surface of the mounting table 106, and measures the amount of displacement of the mounting table 106 in the vertical direction as the spherical surface of the lens 105 is created. Further, a machining liquid 109 in which diamond powder is dispersed in water as abrasive grains 111 is applied to the tool 104 and the lens 1.
Dispenser 110 which is supplied dropwise to the contact portion with the dispenser 05
Is provided.

As shown in FIG. 15, at the lower end of the horn 103, a concave spherical holding portion 103a obtained by inverting the shape of the spherical tool 104 with the same curvature is formed so as to be coaxial with the axis of the horn 103. The tool 104 is arranged in the holding portion 103a, so that the tool 104 is held so as to roll freely. The horn 103 is formed in a tapered shape that tapers toward the lower end, so that the ultrasonic waves generated by the ultrasonic oscillator 101 can be amplified and transmitted to the tool 104. Further, the holding portion 103 of the horn 103
Since “a” has a shape obtained by inverting the tool 104 with the same curvature, the center of curvature of the spherical tool 104 and the axis of the horn 103 coincide with each other, and accurate machining can be performed.

[0007]

FIGS. 14 to 18 show the above-mentioned problems of the processing apparatus. FIG. 16 shows a state in which the processing position is shifted, and FIG. 17 shows a state in which the direction of processing is inclined. FIG. 18A shows a concave spherical surface 1 formed on the lens 105.
FIG. 18B shows a state in which the concave surface 05a is shifted, and FIG. 18B shows a state in which the concave spherical surface 105a created in the lens 105 is deformed into an elliptical shape.

[0008] As shown in FIG. 14, in a tool shaft portion 140, an ultrasonic oscillator 101 attached to a guide 121 is provided.
And the horn 103 holding the spherical tool 104 are separated via the shaft 102. Therefore, the tool shaft 1
40 is bent, and the horn 103 is several tens μm in the lateral direction with respect to the ultrasonic oscillator 101 attached to the guide 121.
It is possible to shift to some extent. The horn 103
When the spherical surface creation processing of the lens 105 is performed in a state where
As shown in FIG. 16, there is a problem that the created concave spherical surface 105a is formed with a displacement of about several tens μm from a desired position.
In FIG. 16, a chain line is a target position, and processing is actually performed with a shift as shown by a solid line.

[0009] When the same horn 103 is used to repeat the spherical surface forming processing a plurality of times, the concave spherical holding portion 103 is formed.
a wears out. Thereby, as shown in FIG.
A difference in curvature occurs between the concave spherical holding portion 103a and the spherical tool 104, and the lateral movement restriction of the tool 104 is weakened. In this state, when the spherical surface creation processing is performed on the lens 105, the processing proceeds while being inclined with respect to the axis of the tool shaft 140 and the work shaft 141. That is, as shown in FIG. 17, the processing by the spherical tool 104 proceeds in the direction of arrow N from the dashed line position to the solid line position.

As a result, as shown in FIG.
The created concave spherical surface 105a is formed so as to be displaced from a desired position, or as shown in FIG.
There is a problem in that the cross-sectional shape becomes elliptical. In FIG. 18, a chain line is a target processing position, and an actual processing position is shifted as shown by a solid line.

As described above, when the tool 104 held by the horn 103 is apt to move in the lateral direction due to the bending of the tool shaft 140 or the wear of the holding portion 103a of the horn 103, the lens 105 is moved. The tool 104 vibrates largely in the lateral direction during the spherical surface creation of
Abut on the edge of the concave surface 105a,
There is a problem that chipping or the like may occur.

In addition to this, as described above, the lens 10
In the case where the position of the concave spherical surface 105a created in FIG. 5 is shifted from the target position, the outer periphery of the lens 105 is post-processed so that the position of the concave spherical surface 105a becomes the target position in the finished product of the lens 105. It is necessary to grind. In the case of performing such outer peripheral grinding, there is a problem that a large amount of lens material is discarded as a grinding allowance, and the number of steps increases various costs such as labor, labor, and time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and prevents the position at which a concave spherical surface is formed from shifting when forming a concave spherical surface. Provided are an apparatus and a method for processing a spherical surface of a concave spherical surface, which can prevent the cross-sectional shape of the spherical surface from being formed in a shape other than the circular shape, and can further prevent the occurrence of burrs, chips, and the like at the edges of the concave spherical surface. The purpose is to:

[0014]

In order to achieve the above object, a machining apparatus according to the first aspect of the present invention is directed to a machining apparatus in which a spherical tool which vibrates ultrasonically is brought into contact with a workpiece to form a concave spherical surface on which the spherical tool is transferred. In a machining apparatus for forming a concave spherical surface on a workpiece, there is provided a movement restricting means for contacting the spherical tool and restricting a traveling direction of the spherical tool during machining.

In the present invention, since the movement restricting means restricts the traveling direction of the spherical tool during machining, machining proceeds without the spherical tool being displaced with respect to the workpiece. For this reason, a concave spherical surface on which the spherical tool is accurately transferred can be created on the workpiece.

According to a second aspect of the present invention, there is provided the apparatus for processing a concave spherical surface according to the first aspect, wherein the movement restricting means has an abutting surface which abuts at least three sides with respect to the side of the spherical tool. It is a movement restricting member.

Since the movement restricting member abuts from three sides to the side of the spherical tool, the traveling direction of the spherical tool during machining can be reliably limited, and the spherical tool can be moved relative to the workpiece. A concave spherical surface on which the spherical tool is accurately transferred can be created on the workpiece without displacement.

According to a third aspect of the present invention, in the apparatus for processing a concave spherical surface according to the first aspect, the movement restricting means has a restriction hole for restricting the traveling direction of the spherical tool when the spherical tool is inserted. It is a movement restricting jig attached to a work holding member that holds a workpiece.

According to the present invention, since the regulating hole of the movement restricting jig restricts the traveling direction of the spherical tool, the spherical tool is not displaced with respect to the workpiece, and a highly accurate concave spherical surface is formed on the workpiece. Can be created. In addition, by attaching the movement limiting jig to the work holding member that holds the workpiece, the relative positioning between the spherical tool and the workpiece is performed via the movement limiting jig. Therefore, the positioning of the spherical tool with respect to the workpiece can be easily performed.

According to a fourth aspect of the present invention, there is provided the apparatus for processing a concave spherical surface according to the third aspect, wherein a supply hole for supplying a processing liquid to a processing portion of the workpiece is formed in the movement restricting jig. It is characterized by the following.

According to the present invention, since the processing liquid is supplied to the processing part from the supply hole of the movement limiting jig, the supply of the processing liquid can be reliably performed, and the processing proceeds smoothly.

According to a fifth aspect of the present invention, there is provided the apparatus for machining a concave spherical surface according to any one of the first to fourth aspects, wherein a horn for transmitting ultrasonic vibration is in contact with the spherical tool. The contact surface is flat.

By making the contact surface of the horn flat as described above, the horn can contact the spherical tool at an arbitrary position, and the horn can be easily machined.

According to a sixth aspect of the present invention, there is provided a machining method of a concave spherical surface, wherein a spherical tool which ultrasonically vibrates is brought into contact with a workpiece to create a concave spherical surface on which the spherical tool is transferred. It is characterized in that a concave spherical surface is created on a workpiece while restricting the traveling direction of a spherical tool during machining.

In the present invention, since the workpiece is machined while restricting the traveling direction of the spherical tool, the machining proceeds without any positional shift of the spherical tool with respect to the workpiece, and the spherical tool can be accurately adjusted. The transferred concave spherical surface can be created on the workpiece.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments shown in the drawings. In each embodiment, the same members are denoted by the same reference numerals and correspond to each other.

(Embodiment 1) FIGS. 1 to 5 show Embodiment 1 of the present invention. FIG. 1 is a front view of a processing apparatus, FIG. 2 is a side view thereof, FIG. FIG. 4 is a plan view thereof, and FIG. 5 is a sectional view showing a state of a spherical surface forming process.

As shown in FIGS. 1 and 2, in this processing apparatus, the work shaft 30 is disposed below and the tool shaft 31 is disposed above and opposed to each other.

The work shaft 30 has a lens holder 10 for holding and fixing the lens 1 as a workpiece, and a pressure cylinder 11 for supporting the lens holder 10. The lens holding base 10 functions as a work holding member. The pressurizing cylinder 11 acts as a pressurizing unit that presses the lens holder 10 upward in a state where the lens 1 and the spherical tool 2 are in contact with each other and applies a load in the direction of the tool shaft 31.

A measurement shaft portion 12a of the micrometer 12 is in contact with the upper surface of the lens holding base 10, so that the amount of displacement of the lens holding base 10 in the vertical direction can be measured as the spherical surface of the lens 1 is formed. It has become. The micrometer 12 functions as a measuring unit for measuring the amount of displacement of the lens holder 10.

The tool shaft 31 can be moved up and down along a guide 20 which is attached to the top of a stand (not shown) so as to face up and down, and this movement is fixed at a fixed position. ing. The tool shaft portion 31 includes an ultrasonic oscillator 2 whose output is controlled by the controller 21.
2 and a shaft 23 provided integrally with the lower end of the ultrasonic oscillator 22.

The horn 3 is fixed to the lower end of the shaft 23. The horn 3 is formed in a tapered shape that tapers toward the lower end, so that the ultrasonic waves generated by the ultrasonic oscillator 22 can be amplified and transmitted to the spherical tool 2. At the lower end of the horn 3, there is formed a concave spherical holding portion 3a obtained by inverting the spherical tool 2 with the same curvature,
By disposing the spherical tool 2 in the holding portion 3a,
It is held so that it can roll freely.

As shown in FIG. 2, on the tool shaft 31 side, a working fluid 6 in which diamond powder as abrasive grains is dispersed in water is applied to the contact portion between the lens 1 and the spherical tool 2. The dispenser 7 which supplies by dripping is provided. The dispenser 7 functions as a working fluid supply unit that supplies the working fluid 6.

In this embodiment, three guides 5 are attached to a base (not shown) horizontally and radially with respect to the central axes of the work shaft 30 and the tool shaft 31. Each of the guides 5 is provided so that the movement restricting rod 4 can move forward and backward and stop at a fixed position. By being provided on each guide 5, the movement restricting bar 4 is arranged in a radial direction with respect to the central axis of the work shaft 30 and the tool shaft 31.

As shown in FIGS. 3 and 4, the three movement restricting rods 4 have abutting surfaces 4a at their tip surfaces, and the abutting surfaces 4a are on the side of the spherical tool 2 that has abutted against the lens 1. 3 towards
Contact. By this abutment, the movement restricting bar 4 sandwiches the spherical tool 2 from the side, thereby determining the horizontal position of the spherical tool 2. Therefore, the movement restricting rod 4 constitutes a movement restricting member (movement restricting means) for restricting the movement of the spherical tool 2 in the horizontal direction.

When the spherical tool 2 is sandwiched between the three movement restricting rods 4, the distance between the spherical tool 2 and the movement restricting rod 4 is 2 mm.
A gap of about μm is provided, and the spherical tool 2 is held so as to roll freely. When the movement limiting rod 4 positions the spherical tool 2,
The tool shaft portion 31 is slightly deformed, and the holding portion 3 of the horn 3 is
The position of a is adjusted to the position of the spherical tool 2.

In the case of performing the spherical surface creation processing by the above configuration, the working fluid 6 is supplied to the contact portion through the dispenser 7 in a state where the lens 1 and the spherical tool 2 are in contact with each other.
Further, the spherical tool 2 is sandwiched between the movement restriction bars 4 from the side.
Thereby, the spherical tool 2 is positioned within a radius of 3 μm from the center position of the upper surface of the lens 1.

Next, the lens 1 is moved by the pressure cylinder 11.
Is pressed against the spherical tool 2, the ultrasonic oscillator 22 is operated by the controller 21, and the ultrasonic vibration is transmitted to the spherical tool 2 via the shaft 23 and the horn 3. By this ultrasonic vibration, the spherical tool 2 microscopically and instantaneously repeatedly contacts and separates from the lens 1 and the horn 3, and the abrasive grains contained in the interposed machining fluid 6 grind the lens 1.

At the time of this grinding, the horn 3
And the movement limiting rod 4 so as to be able to roll freely, and because the work liquid 6 having low viscosity interposed between the lens 1 and the lens 1 is free to roll, it is rolled by ultrasonic vibration. By these behaviors, a concave spherical surface 1a on which the shape of the spherical tool 2 is transferred is created on the lens 1 as shown in FIG.

As the concave spherical surface 1a of the lens 1 is created, the lens holder 10 to which a predetermined load is applied by the pressing cylinder 11 is displaced upward. The displacement amount is read by the micrometer 12, and when the desired grinding amount is reached, the ultrasonic vibration from the ultrasonic oscillator 22 and the application of the load by the pressing cylinder 11 are stopped, and the processing is terminated.

Thereafter, the movement restricting rod 4 is retracted to a position away from the spherical tool 2, and the tool shaft 31 is retracted upward.
The processed lens 1 is removed from the lens holding base 10.
The concave spherical surface 1a is formed at a position within a radius of 3 μm from the center of the upper surface of the lens 1, and the sphericity of the concave spherical surface is formed to be 2 μm or less.

The spherical tool 2 also wears due to the action of the abrasive grains of the working liquid 6 and the ultrasonic vibration, but the rolling causes the wear of each part to be uniform. Therefore, although the radius of curvature of the spherical tool 2 changes, the sphericity does not deteriorate.

In such an embodiment, the movement limiting rod 4
The horizontal position of the spherical tool 2 is determined by
The positioning of the concave spherical surface 1a created in the lens 1 in the horizontal direction can be performed with high accuracy. Along with this, for the purpose of adjusting the position of the concave spherical surface 1a to a desired position,
There is no need to perform outer peripheral grinding of the lens 1 in a post-process, and various costs such as labor and labor can be reduced.

Further, since the horizontal position of the spherical tool 2 is determined by the movement restricting rod 4, the sphericity of the concave spherical surface 1a formed on the lens 1 can be kept good. Also,
There is an effect that it is difficult for chips such as burrs and chips to drop off on the outer peripheral portion of the concave spherical surface 1a of the lens 1.

(Embodiment 2) FIGS. 6 and 7 show Embodiment 2; FIG. 6 is a front view of a processing apparatus, and FIG. 7 is a plan view of a processing portion.

In this embodiment, as the movement restricting member (movement restricting means), instead of the three movement restricting rods 4,
A movement restriction plate 50 and a second movement restriction plate 51 are used. These first movement limiting plate 50 and second movement limiting plate 51
Is disposed on the side of the spherical tool 2 held by the horn 3 and in contact with the lens 1, as shown in FIG.

As shown in FIG. 6, the guide 52 and the guide 5
Reference numerals 3 are mounted horizontally on a stand (not shown), radially with respect to the central axes of the work shaft 30 and the tool shaft 31, and on the same line. The first movement limiting plate 50 and the second movement limiting plate 51 are each provided with a guide 52.
And the guide 53 can be moved forward and backward freely, and these movements are fixed at fixed positions.

As shown in FIG. 6, the first movement restricting plate 50
Has at its end a first contact surface 50a and a second contact surface 50b which are formed in two V-shaped flat surfaces. The second movement restriction plate 51 has a contact surface 51a, which is a single plane, at an end. The first contact surface 50a of the first movement restriction plate 50, the second
The horizontal position of the spherical tool 2 is determined by sandwiching the spherical tool 2 from the side by the contact surface 50b and the contact surface 51a of the second movement restriction plate 51.

In a state where the spherical tool 2 is sandwiched between the first movement limiting plate 50 and the second movement limiting plate 51, 2 μm is provided between the spherical tool 2 and the first movement limiting plate 50 and the second movement limiting plate 51.
A gap of about m is provided, and the spherical tool 2 is held so as to roll freely.

In the case of performing the spherical surface creation processing by the above configuration, the working fluid 6 is supplied to the contact portion through the dispenser 7 in a state where the lens 1 and the spherical tool 2 are in contact with each other.
Further, the spherical tool 2 is moved from the side to the first movement restricting plate 50 and the second
It is sandwiched between the movement restriction plate 51. Thereby, the spherical tool 2 is positioned within a radius of 3 μm from the center position of the upper surface of the lens 1.

Next, the lens 1 is moved by the pressure cylinder 11.
Is pressed against the spherical tool 2, the ultrasonic oscillator 22 is operated by the controller 21, and the ultrasonic vibration is transmitted to the spherical tool 2 via the shaft 23 and the horn 3. By this ultrasonic vibration, the spherical tool 2 microscopically and instantaneously repeatedly contacts and separates from the lens 1 and the horn 3, and the abrasive grains contained in the interposed machining fluid 6 grind the lens 1. The spherical tool 2 includes a horn 3 and a first movement limiting plate 5.
0, since it is rotatably held by the second movement restricting plate 51 and can be rolled freely by the low-viscosity working fluid 6 interposed between the lens 1 and the lens, it rolls by ultrasonic vibration. By these behaviors, a concave spherical surface 1a on which the shape of the spherical tool 2 is transferred is created on the lens 1.

As the concave spherical surface 1a of the lens 1 is created, the lens holder 10 to which a predetermined load is applied by the pressing cylinder 11 is displaced upward. The displacement amount is read by the micrometer 12, and when the desired grinding amount is reached, the ultrasonic vibration from the ultrasonic oscillator 22 and the application of the load by the pressing cylinder 11 are stopped, and the processing is terminated.

Thereafter, the first movement limiting plate 50 and the second movement limiting plate 51 are retracted to a position away from the spherical tool 2, the tool shaft 31 is retracted upward, and the processed lens 1 is moved to the lens holding base 10. Remove from The concave spherical surface 1a of the lens 1 is created at a position within a radius of 3 μm from the center of the upper surface of the lens 1, and the sphericity of the concave spherical surface 1a is formed to be 2 μm or less.

The spherical tool 2 also wears due to the action of the abrasive grains of the working liquid 6 and the ultrasonic vibration, but the rolling causes the wear of each part to be uniform. Therefore, although the radius of curvature of the spherical tool 2 changes, the sphericity does not deteriorate.

In such an embodiment, in the movement restricting means for restricting the movement of the spherical tool 2, the object whose position is to be controlled is three movement restriction rods and two movement restriction plates 5
It is reduced to 0.51. Therefore, there is an effect that the positioning of the spherical tool in the horizontal direction can be performed more easily. Other effects are the same as those of the first embodiment.

(Embodiment 3) FIGS. 8 and 9 show Embodiment 3 of the present invention. FIG.
FIG. 9 is a perspective view of the movement restriction jig 60. In this embodiment, a movement restricting jig 60 shown in FIG. 9 is used as the movement restricting means.

As shown in FIG. 8, the lens holding base 10 of the work shaft 30 as the work holding member holds and fixes the lens 1 at the center of the upper surface. Also, the lens holder 10
Has a concentric step 10a and a flange 10b lower than the step 10a on the outside thereof.
The movement restricting jig 60 is held and fixed by a and the flange portion 10b.

The movement limiting jig 60 has a substantially cylindrical shape, and has a large-diameter hole 60a formed at a lower portion and a small-diameter hole 60b formed at an upper portion. The diameter of the large-diameter hole 60a of the movement limiting jig 60 is only about 3 μm larger than the diameter of the step portion 10a of the lens holding base 10, and by fitting them, the movement limiting jig 60 allows the lens holding base 10 to move. Fixed on top. At this time, the lens 1 held and fixed on the lens holding base 10 fits inside the large-diameter hole 60 a of the movement limiting jig 60.

The spherical tool 2 is inserted into the small diameter hole 60b of the movement limiting jig 60, and the spherical tool 2 comes into contact with the lens 1 by this insertion. In this case, the diameter of the small diameter hole 60b is
The diameter of the spherical tool 2 is only about 3 μm larger than the diameter of the spherical tool 2, and the horizontal movement of the spherical tool 2 is restricted by inserting the spherical tool 2 into the small-diameter hole 60b. Movement restriction jig 6
The spherical tool 2 inserted into the small-diameter hole 60b can roll freely in the small-diameter hole 60b, but is restricted from moving in the horizontal direction by the small-diameter hole 60b. For this reason, the small-diameter hole 6
Reference numeral 0b denotes a restriction hole for restricting the moving direction of the spherical tool 2.

In addition to the above, the movement restricting jig 60 is provided with a working liquid supply hole 60c. This supply hole 60
c is formed so as to penetrate into the large-diameter hole 60a from the bottom surface on the small-diameter hole 60b side, whereby the distal end portion of the dispenser 7 can enter the inside of the movement restriction jig 60. . The dispenser 7 can move forward and backward along guide means (not shown).
Through the inside of the 0 supply hole 60c, the front end portion can approach the processing portion which is the contact portion between the lens 1 and the spherical tool 2.

The horn 3 of the tool shaft 31 arranged above
As in the first embodiment, a concave spherical holding portion 3a obtained by inverting the spherical tool 2 with the same curvature is formed at the lower end of the holding member 3a. The spherical tool 2 is rotatably held by being arranged in the holding portion 3a.

In the case of performing the spherical surface creation processing by the above configuration, the movement limiting jig 60 is fixed to the lens holding base 10 for holding and fixing the lens 1. Next, the spherical tool 2 is inserted into the small-diameter hole 60 b of the movement limiting jig 60 and is brought into contact with the lens 1. Thereby, the spherical tool 2 is positioned within a radius of 3 μm from the center position of the upper surface of the lens 1.

Next, the dispenser 7 is moved to approach the contact portion between the lens 1 and the spherical tool 2 through the supply hole 60c of the movement restricting jig 60, and this contact portion (working portion)
Is supplied with the machining liquid 6.

After that, the tool shaft 31 is moved, and the holding portion 3 a of the horn 3 is brought into contact with the spherical tool 2. Next, the pressing cylinder 11 presses the lens 1 against the spherical tool 2, and the controller 21 controls the ultrasonic oscillator 22.
Is operated, and the ultrasonic vibration is propagated to the spherical tool 2 through the shaft body 23 and the horn 3. By this ultrasonic vibration,
The spherical tool 2 microscopically and instantaneously repeatedly contacts and separates from the lens 1 and the horn 3, and the abrasive grains contained in the intervening working fluid 6 grind the lens 1. The spherical tool 2 is rotatably held by the horn 3 and the movement restricting jig 60, and can be rolled by the low-viscosity working fluid 6 interposed between the spherical tool 2 and the lens 1. Therefore, the spherical tool 2 rolls by ultrasonic vibration. . By these behaviors, a concave spherical surface 1a on which the shape of the spherical tool 2 is transferred is created on the lens 1.

As the concave spherical surface 1a of the lens 1 is created, the lens holder 10 to which a predetermined load is applied by the pressing cylinder 11 is displaced upward. The displacement amount is read by the micrometer 12, and when the desired grinding amount is reached, the ultrasonic vibration from the ultrasonic oscillator 22 and the application of the load by the pressing cylinder 11 are stopped, and the processing is terminated. Thereafter, the tool shaft 31 is retracted upward, and the movement limiting jig 6 is moved.
0 and remove the processed lens 1 into the lens holder 10
Remove from

The concave spherical surface 1a is formed at a position within a radius of 3 μm from the center of the upper surface of the lens 1, and the sphericity of the concave spherical surface is 2 μm.
It is formed below. Although the spherical tool 2 is also worn by the action of the abrasive grains of the working fluid 6 and the ultrasonic vibration, the rolling makes the wear amount of each part uniform. Therefore, although the radius of curvature of the spherical tool 2 changes, the sphericity does not deteriorate.

In this embodiment, since the movement limiting jig 60 fixed to the lens holder 10 is used as the movement limiting means of the spherical tool 2, the movement limiting rod 4 and the movement limiting plate 5 are used.
There is no need to control the position as in 0, 51, and the positioning of the spherical tool 2 in the horizontal direction can be performed more easily. Other effects are the same as those of the first embodiment.

(Fourth Embodiment) FIGS. 10 and 11 show a fourth embodiment. FIG. 10 is a front view of a processing apparatus.
5 is a cross-sectional view of the lens holding tray 70 to which the movement restriction jig 60 is attached. The lens holding plate 70 serves as a work holding member for holding the movement limiting jig 60, and is attached to the lens holding base 71 as shown in FIG.

As shown in FIG. 11, a concave holding portion 70a is formed at the center of the upper surface of the lens holding tray 70, and the lens 1 is fixed to this holding portion 70a by bonding. A step portion 70b is formed concentrically around the outer periphery of the concave holding portion 70a. The diameter of the step portion 70b is smaller than the diameter of the large diameter portion 60a of the movement limiting jig 60 by about 3 μm.
A substantially cylindrical body 70c coaxial with the holding part 70a and the step part 70b is formed below the lens holding plate 70, and the body 70c fits on the work holding base 71 as described later. The work holding plate 70 is attached to the work holding base 71 by the combination.

At the step 70b of the lens holding tray 70, a movement restricting jig 60 is disposed. Further, the spherical tool 2 is inserted into the small diameter hole (restriction hole) 60b of the movement restricting jig 60, and the lens 1 is moved.
Contact. This restricts the horizontal movement of the spherical tool 2 on the lens holding plate 70.

As shown in FIG. 11, the work shaft portion 30 located below has a work holding table 71 for holding and fixing the lens holding plate 70 and a pressure cylinder 11 for supporting the work holding table 71. On the upper surface of the work holding table 71, a holding hole 71 having a diameter to be fitted with the body 70 c of the lens holding tray 70.
is formed, and the lens holding tray 70 is held and fixed in the holding hole 71a. At this time, the flange portion 70 d on the outer peripheral side of the work holding plate 70 is supported on the upper surface of the work holding base 71.

The horn 3 of the tool shaft 31 is brought into contact with the lens 1 on the lens holding plate 70 and the spherical tool 2 held by the movement limiting jig 60 from above. The pressure cylinder 11 acts so as to press the work holding table 71 upward in a state where the lens 1 and the spherical tool 2 are in contact with each other, and apply a load in the direction of the tool shaft 31.

The micrometer 12 is in contact with the upper surface of the work holding base 71 in the same manner as in FIG. 2, and the amount of displacement of the work holding base 71 in the vertical direction can be measured as the spherical surface of the lens 1 is formed. It has become.

In the case of performing the spherical surface creation processing by the above configuration, the movement limiting jig 60 is fixed to the lens holding plate 70 for holding and fixing the lens 1, and further, the spherical tool 2 is moved to the small diameter hole (regulation) of the movement limiting jig 60. Hole 60b and brought into contact with the lens 1. As a result, the spherical tool 2 is positioned on the lens holding plate 70 within a radius of 3 μm from the center position of the upper surface of the lens 1. Next, the lens holding plate 70 to which the lens 1, the movement limiting jig 60, and the spherical tool 2 are attached is arranged on the work holding base 71.

Thereafter, the dispenser 7 is moved to approach the contact portion between the lens 1 and the spherical tool 2 through the supply hole 60c of the movement restricting jig 60, and the working fluid 6 is applied to the contact portion (working portion). Supply.

Next, the tool shaft 31 is moved, and the horn 3
Is brought into contact with the spherical tool 2. The lens 1 is pressed against the spherical tool 2 by the pressurizing cylinder 11, and the ultrasonic oscillator 22 is operated by the controller 21 to propagate the ultrasonic vibration to the spherical tool 2 via the shaft 23 and the horn 3. By this ultrasonic vibration, the spherical tool 2 microscopically and instantaneously repeatedly contacts and separates from the lens 1 and the horn 3, and the abrasive grains contained in the interposed machining fluid 6 grind the lens 1.

Further, the spherical tool 2 is rotatably held by the horn 3 and the movement limiting jig 60 and can be rolled by the low viscosity working fluid 6 interposed between the spherical tool 2 and the lens 1. Rolls by vibration. By these behaviors, a concave spherical surface 1a on which the shape of the spherical tool 2 is transferred is created on the lens 1.

As the concave spherical surface 1a of the lens 1 is created, the work holding table 71 on which a predetermined load is applied by the pressing cylinder 11 is displaced upward. The displacement amount is read by the micrometer 12, and when the desired grinding amount is reached, the ultrasonic vibration from the ultrasonic oscillator 22 and the application of the load by the pressing cylinder 11 are stopped, and the processing is terminated.

The tool shaft 31 is retracted upward, and the lens holding tray 70 is removed. Further, the movement restriction jig 60 is removed from the lens holding plate 70. The lens 1 is polished in a later step while being fixed to the lens holding plate 70.

The concave spherical surface 1a is formed at a position within a radius of 3 μm from the center of the upper surface of the lens 1, and the sphericity of the concave spherical surface is 2 μm.
It is formed below.

In this embodiment, as the means for restricting the movement of the spherical tool 2, the movement restricting jig 60 and the spherical tool 2 are attached to the lens holding plate 70 as a lens holding member for fixing and holding the lens. The work can be performed outside the processing device, and the time during which the lens 1 as a workpiece stays in the processing device can be reduced.

Further, since the processing is performed in a state where the lens 1 is fixed and held on the lens holding plate 70, it is not necessary for an operator or a gripper of the processing apparatus to directly contact the lens 1.
The damage of the lens 1 can be prevented. In addition, even when the lens 1 is small, by handling the lens alone,
The loss of the lens can be prevented. Further, since the lens holding plate 70 for fixing the lens 1 holds the movement limiting jig 60, there is no need to control the position like a movement limiting rod or a movement limiting plate, and the spherical tool 2 can be positioned horizontally. It can be performed more easily. Other effects are similar to those of the third embodiment.

(Fifth Embodiment) FIG. 12 is a sectional view of a fifth embodiment.

As shown in FIG. 12, the lens 1, which is the workpiece, is fixed by being held by the lens holding base 10 of the work shaft 30 arranged below. The lower end surface of the horn 80 of the tool shaft portion 31 has a flat contact surface 80.
The contact surface 80a is in contact with the spherical tool 2.

As shown in FIG. 4, on the side of the spherical tool 2 in contact with the lens 1 and the horn 80, there is provided a movable shaft 3 which is movable in the radial direction with respect to the center axis of the work shaft 30 and the tool shaft.
The movement restriction rods 4 abut on each other, and determine the horizontal position of the spherical tool 2. When the spherical tool 2 is sandwiched between the three movement restricting rods 4, a gap of about 2 μm is provided between the spherical tool 2 and the movement restricting rod 4, and the spherical tool 2 is held so as to roll freely. The movement restricting rod 4 functions as a means for restricting the movement of the spherical tool 2 in the horizontal direction.

In this configuration, the lens 1 is pressed against the spherical tool 2 by the pressurizing cylinder 11, and the ultrasonic oscillator 22 is operated by the controller 21 so that the shaft 23
Then, the ultrasonic vibration is propagated to the spherical tool 2 via the horn 80. Due to the ultrasonic vibration, the spherical tool 2 microscopically and instantaneously repeatedly comes into contact with and separates from the lens 1 and the horn 3, and the abrasive grains contained in the intervening machining fluid 6 are removed from the lens 1.
Grinding.

The spherical tool 2 is rotatably held by the horn 80 and the movement restricting rod 4 and is rotatable by the low-viscosity machining fluid 6 interposed between the spherical tool 2 and the lens 1. Rolls by ultrasonic vibration. By these behaviors, a concave spherical surface 1a on which the shape of the spherical tool 2 is transferred is created on the lens 1.

In this embodiment, the contact surface 80a at the lower end of the horn 80 that contacts the spherical tool 2 is flat, so that the spherical tool 2 and the contact surface 80a are in point contact at the beginning of machining. Touch with. Then, simultaneously with the processing of the lens 1, the spherical surface generation processing of the contact surface 80 a of the horn 80 also proceeds, and a concave spherical surface is formed. In this case, the same horn 8
In the case of performing the machining a plurality of times using 0, the concave spherical surface created on the contact surface 80a of the horn 80 is
a that the horn 8 is not eccentric with respect to the desired position;
The condition is that the concave spherical surface created on the zero contact surface 80a is not too deep.

In such an embodiment, since the concave spherical shape obtained by inverting the spherical tool 2 is not formed on the contact surface 80a of the horn 80, the labor and labor required for manufacturing the horn 80 can be reduced. it can. Along with this, it is easy to prepare a large number of horns and increase the horn replacement frequency.

In the horn having the concave spherical holding portion, the horizontal position of the spherical tool held by the horn is determined by the movement restricting means. Therefore, the horizontal position differs between the tool shaft having the horn and the spherical tool. In this case, the tool shaft may be deformed. On the other hand, in this embodiment, the contact surface 80a of the horn 80 that contacts the spherical tool 2
Is flat, the horn 80 does not have a horizontal positioning function for the spherical tool 2, so that deformation of the tool shaft can be prevented. Further, since the spherical tool 2 can contact the contact surface 80a of the horn 80 at an arbitrary position, the tool shaft 31 having the horn 80 does not need to be positioned with high accuracy. Other effects are the same as those of the first embodiment.

(Embodiment 6) FIG. 13 is a front view of a processing apparatus according to Embodiment 6 of the present invention.

As shown in FIG. 13, the lens 1 to be processed is held and fixed by the lens holder 10 of the work shaft 30 arranged below. Lens holder 10
Is fixed to a stand not shown.

The horn 3 of the tool shaft 31 arranged above
As shown in FIG. 3, a concave spherical holding portion 3a obtained by inverting the spherical tool 2 with the same curvature is formed at the lower end of the holding member 3a. The spherical tool 2 is rollably held by being arranged in the holding portion 3a.

As shown in FIG. 4, the spherical tool 2 held by the horn 3 and in contact with the lens 1 is moved back and forth in the radial direction with respect to the center axis of the work shaft 30 and the tool shaft. Three freely movable movement restricting rods 4 come into contact with each other and determine the horizontal position of the spherical tool 2. When the spherical tool 2 is sandwiched between the three movement restricting rods 4, a gap of approximately 2 μm is provided between the spherical tool 2 and the movement restricting rod 4, and the spherical tool 2 is held so as to roll freely. The movement restriction bar 4 acts as a hand for restricting the movement of the spherical tool 2 in the horizontal direction, as in the first embodiment.

The tool shaft 31 is vertically movable along a guide 20 attached to the upper part of a gantry (not shown). The tool shaft portion 31 is screwed with a ball screw 91 connected to a drive shaft 90a of a motor 90 mounted on the upper part of the gantry. Therefore, when the motor 90 is driven, the entire tool shaft portion 31 moves in the vertical direction. In this embodiment, the upper part of the ultrasonic oscillator 22 of the tool shaft 31 is screwed with the ball screw 91.

The driving of the motor 90 is controlled by a motor controller 92. By controlling the motor 90 by the motor controller 92, the moving amount of the tool shaft 31, that is, the load applied downward can be set. Therefore, the motor 90 acts as a pressurizing unit that presses the horn 3 downward while the lens 1 and the spherical tool 2 are in contact with each other and applies a load in the direction of the work shaft 30. In addition, the motor 90 and the motor controller 92
Also functions as a measuring means for measuring the amount of displacement of the tool shaft 31.

[0097] The tool shaft 31 is
An ultrasonic oscillator 22 whose output is controlled by the ultrasonic oscillator 22 and a shaft 23 integrally provided at the lower end of the ultrasonic oscillator 22 are provided, and the horn 3 is fixed to the lower end of the shaft 23. The horn 103 is formed in a tapered shape that tapers toward the lower end, so that the ultrasonic waves generated by the ultrasonic oscillator 22 can be amplified and transmitted to the spherical tool 2.

Also in this embodiment, the first embodiment
Similarly, three guides 5 and three movement restricting caps 4 are arranged. Each of the three guides 5 is mounted horizontally on a stand (not shown) and radially with respect to the central axes of the work shaft 30 and the tool shaft. 3
Each of the movement restricting rods 4 is located on the side of the spherical tool 2, is capable of moving forward and backward along a guide 5, and is fixed at a fixed position. These movement restricting rods 4 can sandwich the spherical tool 2 from the side, and act as movement restricting means for restricting the spherical tool 2 from moving in the horizontal direction.

Although not shown, the dispenser 7
Is provided, and a working liquid 6 in which diamond powder is dispersed in water as abrasive grains is dropped and supplied to a contact portion between the lens 1 and the spherical tool 2.

When a concave spherical surface is to be formed by the above configuration, the working fluid 6 is supplied to the contact portion through the dispenser 7 while the lens 1 and the spherical tool 2 are in contact with each other. Further, the spherical tool 2 is sandwiched between the movement restriction bars 4 from the side. Thereby, the spherical tool 2 is positioned within a radius of 3 μm from the center position of the upper surface of the lens 1.

Next, the motor 90 is operated by the motor controller 92 to press the spherical tool 2 held by the horn 3 against the lens 1 and the ultrasonic oscillator 22 is operated by the controller 21 to move the shaft 23 and the horn 3 together. The ultrasonic vibration is propagated to the spherical tool 2 through the above.

Due to the ultrasonic vibration, the spherical tool 2 microscopically and instantaneously repeatedly comes into contact with and separates from the lens 1 and the horn 3, and the abrasive grains contained in the interposed machining fluid 6 grind the lens 1. To go. Further, the spherical tool 2 is rotatably held by the horn 3 and the movement restricting rod 4 and is rotatable by the low-viscosity working fluid 6 interposed between the lens 1 and the ultrasonic tool. Rolls by vibration. By these behaviors, a concave spherical surface 1a on which the shape of the spherical tool 2 is transferred is created on the lens 1.

As the concave spherical surface 1a of the lens 1 is created, the tool shaft 31 to which a predetermined load is applied by the motor 90 is displaced downward. Motor controller 92
Measures the amount of displacement, stops the ultrasonic vibration from the ultrasonic oscillator 22 and the application of the load by the pressurizing cylinder 11 when the desired grinding amount is reached, and ends the machining.

Thereafter, the movement restricting rod 4 is retracted to a position away from the spherical tool 2, and the tool shaft 31 is retracted upward.
The processed lens 1 is removed from the lens holding base 10.
The concave spherical surface 1a is formed at a position within a radius of 3 μm from the center of the upper surface of the lens 1, and the sphericity of the concave spherical surface is formed to be 2 μm or less.

The spherical tool 2 also wears due to the action of the abrasive grains of the working liquid 6 and the ultrasonic vibration, but the rolling causes the wear of each part to be uniform. Therefore, although the radius of curvature of the spherical tool 2 changes, the sphericity does not deteriorate.

In such an embodiment, when setting the vertical position of machining, not the method of displacing both the work shaft 30 and the tool shaft 31 but the method of displacing only the tool shaft 31. Therefore, there is an effect that the number of operation targets at the time of processing is reduced and the operation is facilitated. Other effects are the same as those of the first embodiment.

The present invention is not limited to the above embodiment, but can be variously modified. For example, in Embodiments 1 to 6 of the present invention, the workpiece uses the columnar lens 1, but may have another shape or another material in which a concave spherical surface is created.

In the first to sixth embodiments, the movement restricting means abuts on the side surface of the spherical tool 2 at three points or in a circumferential shape, but a structure capable of holding while restricting the movement in the horizontal direction. If so, another configuration may be used.

In the first to sixth embodiments, the concave spherical surface is created at the center of the upper surface of the cylindrical lens 1. However, by changing the position setting of the spherical tool 2 by the movement restricting means, an arbitrary position on the upper surface of the lens can be obtained. A concave spherical surface can be created.

In the first to fifth embodiments, the pressing cylinder of the work shaft is used as the pressing means. However, other means may be used as long as a predetermined load can be applied during processing. .

In the sixth embodiment, the motor 90 is used as the means for pressing the tool shaft 31. However, other means such as a cylinder may be used as long as a predetermined load can be applied during machining. good.

In the first to fifth embodiments of the present invention, the micrometer 12 is used as the processing amount measuring means. However, other means may be used as long as the processing amount can be measured with high accuracy.

Further, a plurality of components shown in the first to sixth embodiments may be combined.

[0114]

According to the first aspect of the present invention, since the movement limiting means limits the traveling direction of the spherical tool during machining,
Machining proceeds without the spherical tool being displaced with respect to the workpiece. For this reason, a concave spherical surface on which the spherical tool is accurately transferred can be created on the workpiece with high precision. Further, since the movement restricting means determines the horizontal position of the spherical tool, it is not necessary to set the relative position in the horizontal direction between the work shaft and the tool shaft with high accuracy. Furthermore, since the concave spherical surface can be created at a desired position, there is no need to perform outer peripheral grinding of the workpiece in a post-process for adjusting the position of the concave spherical surface to the desired position, thereby reducing labor and labor. can do. Furthermore, since the movement restricting means restricts the movement of the spherical tool in a direction other than the desired direction during machining, the sphericity of the concave spherical surface created on the workpiece can be kept good. Drops such as burrs and chips are less likely to occur at the outer peripheral portion of the concave spherical surface of the workpiece.

According to the second aspect of the present invention, in addition to having the same effect as the first aspect of the present invention, the movement limiting member for limiting the traveling direction of the spherical tool during machining is provided by the three-way spherical tool. Since it abuts on the side, the traveling direction of the spherical tool can be reliably restricted.

According to the third aspect of the present invention, in addition to having the same effect as the first aspect of the present invention, since the regulating hole of the movement restricting jig restricts the traveling direction of the spherical tool, a highly accurate concave is provided. Since a spherical surface can be created on the workpiece and the movement limiting jig is attached to the work holding member that holds the workpiece, the positioning of the spherical tool with respect to the workpiece can be performed easily.

According to the fourth aspect of the present invention, in addition to having the same effect as the third aspect of the present invention, since the machining fluid can be supplied to the machining portion from the supply hole of the movement limiting jig, the machining fluid can be reliably supplied. And the processing proceeds smoothly.

According to the fifth aspect of the present invention, in addition to having the same effects as the first to fourth aspects of the present invention, the horn has a flat contact surface, so that the horn can be arbitrarily positioned. The horn can be in contact with the spherical tool, and the horn can be easily machined.

According to the sixth aspect of the present invention, since the workpiece is machined while restricting the traveling direction of the spherical tool, the machining proceeds without any positional displacement of the spherical tool with respect to the workpiece. A concave spherical surface can be created on a workpiece with high precision.

[Brief description of the drawings]

FIG. 1 is a front view of a processing apparatus according to a first embodiment.

FIG. 2 is a side view of the processing apparatus according to the first embodiment.

FIG. 3 is a cross-sectional view of a processed part according to the first embodiment.

FIG. 4 is a plan view of a processed part according to the first embodiment.

FIG. 5 is a cross-sectional view of Embodiment 1 at the time of processing.

FIG. 6 is a front view of a processing apparatus according to a second embodiment.

FIG. 7 is a plan view of a processed part according to the second embodiment.

FIG. 8 is a front view of a processing apparatus according to a third embodiment.

FIG. 9 is a perspective view of a movement restriction jig according to a third embodiment.

FIG. 10 is a front view of a processing apparatus according to a fourth embodiment.

FIG. 11 is a cross-sectional view illustrating a state where a movement restriction jig according to a fourth embodiment is attached.

FIG. 12 is a sectional view of a machined part according to the fifth embodiment.

FIG. 13 is a front view of a processing apparatus according to a sixth embodiment.

FIG. 14 is a front view of a conventional processing apparatus.

FIG. 15 is a sectional view of a processing portion of a conventional processing apparatus.

FIG. 16 is a cross-sectional view showing a state where a processing position is shifted by conventional processing.

FIG. 17 is a cross-sectional view showing a state in which a traveling direction is inclined by conventional processing.

FIGS. 18 (a) and (b) show conventional processing
It is a top view which shows the state which the concave spherical surface deformed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lens 1a Concave spherical surface 2 Spherical tool 3 Horn 4 Movement restriction rod 4a Contact surface 50 First movement restriction plate 51 Second movement restriction plate 50a, 50b, 51a Contact surface 60 Movement restriction jig 60b Control hole 60c Supply hole

Claims (6)

[Claims] 1. An apparatus for processing a concave spherical surface, in which a spherical tool that vibrates ultrasonically is brought into contact with a workpiece and a concave spherical surface onto which the spherical tool is transferred is created on the workpiece. An apparatus for machining a concave spherical surface, comprising a movement limiting means for limiting a traveling direction of a spherical tool therein. 2. The processing of a concave spherical surface according to claim 1, wherein said movement restricting means is a movement restricting member having a contact surface that comes into contact with at least three sides of a spherical tool. apparatus. 3. The movement restricting means is a movement restricting jig that has a restriction hole for restricting the traveling direction of the spherical tool when the spherical tool is inserted, and is attached to a work holding member that holds the workpiece. The concave spherical machining apparatus according to claim 1, wherein: 4. The concave spherical processing apparatus according to claim 3, wherein a supply hole for supplying a processing liquid to a processing portion of the workpiece is formed in the movement limiting jig. 5. The horn for transmitting ultrasonic vibrations is in contact with the spherical tool, and the contact surface of the horn is flat. Equipment for processing concave spheres. 6. A method of machining a concave spherical surface, in which a spherical tool that ultrasonically vibrates is brought into contact with a workpiece to create a concave spherical surface on which the spherical tool is transferred, the moving direction of the spherical tool during machining. Forming a concave spherical surface on a workpiece while restricting the surface roughness.