JP3992388B2 - Lens centering machine and lens centering device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  In the present invention, the outer peripheral portion of the lens to be processed is ground to a predetermined dimension in accordance with the optical center axis (optical axis) of the lens to be processed.Lens centering machine and lensThe present invention relates to a centering device.
[0002]
[Prior art]
The prior art will be described with reference to FIGS.
FIG. 6 shows a lens centering method and a centering method described in a lens centering machine according to Japanese Patent No. 2637435. The upper shaft bell holder 62 and the lower shaft bell holder 63 are relatively disposed on the same axis, and the processing lens 61 can be centered by sandwiching the processing lens 61 between the tips of the vertical shaft bell holders 62 and 63. It has become. The vertical shaft bell holders 62 and 63 are synchronously rotated in the same direction (directions of arrows E and F) around the central axis by a drive source (not shown). Are respectively drilled. The same air supply device is connected to each of the circulation holes 64 and 65 via an air supply pipe (not shown), and a fluid path 60 for improving the centering effect of the lens 61 to be processed is configured. 6A shows a state in which the lens 61 to be processed is tilted by an inclination amount θ ° with respect to the central axis and is not centered when being sandwiched between the vertical axis bell holders 62 and 63. FIG. ) Shows a state where the lens 61 to be processed is centered.
[0003]
When centering, the lens 61 to be processed is sandwiched between the vertical axis bell holders 62 and 63 at a low pressure, and the vertical axis bell holders 62 and 63 are synchronously rotated in the same direction, so that fluid (gas) is supplied from the fluid path 60. It ejects in the direction of the lens 61 to be processed. At this time, the fluid flows out from the contact points A to D between the lens surface of the lens 61 to be processed and the vertical axis bell holders 62 and 63, and the lens 61 to be processed is sandwiched between the vertical axis bell holders 62 and 63 through the fluid. The Here, as shown in FIG. 6A, when the lens 61 to be processed is sandwiched with an inclination amount θ °, a large clearance α is formed between the upper shaft bell holder 62 and the lens surface of the lens 61 to be processed. Since a large amount of fluid flows out from the clearance α, the lens 61 to be processed floats and slides easily due to the difference between the upper and lower pressures, coupled with the action of the upper shaft pressure direction G from above the upper shaft bell holder 62. The lens 61 to be processed slides toward the axial center, and the centering of the lens 61 to be processed is completed as shown in FIG. At this time, the fluid flows out from the contacts A to D evenly.
[0004]
After the centering of the lens 61 to be processed is completed, the clamping force of the lens 61 to be processed by the vertical axis bell holders 62, 63 is increased, and the lens 61 to be processed is directly clamped by the tips of the vertical axis bell holders 62, 63. Stop fluid supply. Then, the outer peripheral surface of the lens 61 to be processed is ground to perform the centering process.
[0005]
FIG. 7 shows a lens centering method and apparatus in a lens centering machine disclosed in Japanese Patent Application Laid-Open No. 10-34506. Vertical shaft bell holders 73 and 75 arranged coaxially and rotatably are arranged. A vacuum suction device (not shown) is attached to the lower shaft bell holder 75 and a flow hole 75a is provided in the center thereof to constitute a suction mechanism for the lens 72 to be processed. Further, the center of the center measuring instrument 74 (dial gauge) (on the extension line connecting the center of the lower lens bell holder 75, that is, the center of the lens 72 to be processed centered on the lower shaft bell holder 75 and the center of the grindstone shaft 71) The terminal of the lead measuring instrument 74 can come into contact with the lens surface of the lens 72 to be processed that is sucked and held on the lower shaft bell holder 75.
[0006]
When centering, a dial gauge terminal that is a core measuring device 74 is applied to the lens surface of the lens 72 to be processed that is attracted to the tip of the lower shaft bell holder 75 by the suction mechanism from below the lower shaft bell holder 75. Then, the eccentric amount and the maximum eccentric position of the lens 72 to be processed obtained by rotating the lower shaft bell holder 75 once are obtained, and the grinding wheel shaft 71 is stopped by ½ of the eccentric amount so that the eccentricity is eliminated. The lens 72 to be processed is moved so that the outer peripheral surface of the lens is aligned with the outer periphery of the lens 72 to be processed. Then, when the core of the lens 72 to be processed comes out (that is, the amount of eccentricity disappears by re-measurement), the lens 72 is clamped with a strong force by the vertical axis bell holders 73 and 75, and the core is fixed. Secure. Thereafter, the grindstone shaft 1 is rotated to grind the outer periphery of the lens 72 to be processed, and a centering process is performed.
[0007]
In general, the core accuracy of a bell clamp system for a lens having two radii of curvature with an optical element is expressed by the ratio of the radius of curvature of the lens and the outer diameter of the vertical axis bell holder that holds the lens at the contact point that holds the lens. It is well known in many documents and others that it depends on the coefficient and the coefficient of friction due to the material of the lens and the vertical axis bell holder.
[0008]
Therefore, in the bell clamp system, there is a lens that cannot secure the core accuracy by merely mechanically bell-clamping, and many attempts have been made such as means as shown in the above example.
[0009]
[Problems to be solved by the invention]
However, the upper shaft bell holder 62 and the lower shaft bell holder 63 are used in a lens whose core accuracy cannot be ensured even if the above-described improvement means is attempted, or in a lens whose optical element has been reduced in diameter due to recent progress in computerization. 75, the inner diameter of the flow holes 64, 65, 75a provided in the center is extremely small. In some cases, the flow holes 64, 65, 75a cannot be provided, and there is no hole. These methods of centering are not possible, or the method using the center measuring device 74 cannot secure the vacuum suction force and the contact of the gauge of the center measuring device 74 is extremely difficult. It could not be employed mechanically, so the efficiency of the centering process was poor. For this reason, there has been a problem that it is necessary to employ a cider centering method that requires cleaning in a post-process and performs spun optical centering with poor cleaning efficiency.
[0010]
  Therefore, the present invention has been made in view of the above problems of the prior art, and it is possible to ensure high core accuracy while utilizing the bell clamp method.Lens centering machine and lensAn object is to provide a centering device.
[0013]
[Means for Solving the Problems]
  To achieve the object, claim 1 of the present invention.This lens centering machine performs centering of the lens after centering the lens by sandwiching the lens as the workpiece between the two bell holders whose center axes coincide and face each other. And a vibration applying means for applying mechanical vibration in a direction intersecting the central axis of both or one of the bell holders with the lens sandwiched therebetween,The vibration applying means includes an oscillating device that oscillates mechanical vibration, vibration coupling means that transmits the vibration to both or one of the bell holders, a pressure adjusting spring that adjusts the force of the vibration, and the vibration to the bell holder. A parallel spring applied from a fixed direction to a piezoelectric sensor that is attached to the parallel spring to detect the attenuation of the resonance point of the parallel spring, and is connected to a vibration measuring instrument that outputs the lower limit of the attenuation curve. AndWhile the bell holder is rotated, the bell holder is vibrated to center the lens sandwiched between the bell holders.
[0014]
  Of the present inventionClaim 2The lens centering machineIn claim 1 of the present invention,Clamping force adjustment that changes the clamping force of the lens clamped between bell holdersMeansThe lens holder is centered by rotating the bell holder while applying the vibration by the vibration applying means, and then the lens clamping force by the bell holder is increased, and then the lens is centered. Features.
[0016]
  Furthermore, the present inventionClaim 3This lens centering device is a lens that is arranged in a lens centering machine that performs centering of a lens after centering a lens that is a workpiece between two opposing bell holders having the same center axis. A centering device, a vibration terminal contacting at least one of the bell holders, an oscillation device for applying mechanical vibration to the bell holder via the vibration terminals, and a pressure adjusting spring for adjusting the amount of vibration A holding means for the vibration terminal that applies the vibration so as to intersect the central axis of the bell holder, a piezoelectric sensor that is attached to the holding means and detects attenuation of a resonance point transmitted to the holding means, And a vibration measuring device that outputs a lower limit point of the attenuation curve.
[0017]
  First, the configuration of the present inventionExampleThe centripetal action will be described with reference to FIG. 3 (a) and 3 (b) show two states of the lens to be processed sandwiched between the vertical axis bell holders, and FIG. 3 (c) shows a state in which the lens to be processed is centered.
[0018]
The processed lens 1 is held between the upper shaft bell holder 2 and the lower shaft bell holder 3, and the processed lens 1 is lightly pressed by the upper shaft bell holder 2 in the upper shaft pressing direction g. Here, in a lens having a poor Z coefficient or friction coefficient, for example, as shown in FIGS. 3A and 3B, the optical axis of the lens 1 to be processed is inclined by θ ° with respect to the central axis of the vertical axis bell holders 2 and 3. If it is sandwiched, a clearance α occurs between the tip portion a of the upper shaft bell holder 2 or the tip portion b of the lower shaft bell holder 3 and the lens surface of the lens 1 to be processed. 3 (a) and 3 (b), reference numerals c and d denote an upper shaft bell holder 2 and a lower shaft that contact the lens surface of the lens 1 to be processed when the lens 1 to be processed is inclined by θ °. The tip part of the bell holder 3 is pointed out.
[0019]
At this time, when mechanical vibration is applied to both or one of the upper and lower shaft bell holders 2 and 3 holding the lens 1 in the illustrated vibration direction h, the lens 1 moves in the direction of movement of the lens due to the wedge action. Slightly moves to i (ie, in the direction of vibration). Simultaneously applying this mechanical vibration, simultaneously rotating the upper shaft bell holder 2 in the upper shaft rotation direction e and the lower shaft bell holder 3 in the lower shaft rotation direction f, and applying centrifugal force to the lens 1 to be moved up and down If the state where the shaft bell holders 2 and 3 and the processed lens 1 are easily rubbed is maintained, the action of the upper shaft pressing direction g is also added, and the processed lens 1 gradually moves in the centripetal direction. go. This is the basic centripetal action principle of the present invention.
[0020]
Incidentally, mechanical vibration and wedge action will be described with reference to FIG. The figure shows a carpenter tool. A main blade k and a back blade l sandwiched between a cannula base j and a stop pin m provided thereon are inserted. Now, when an impact is applied to the cannula table j with the hammer n in the direction of the hammer external force acting direction o, the main blade k moves in the direction of the main blade movement direction p due to the wedge action. On the other hand, when an impact is applied from the opposite side of the hammer operating force o direction, the main blade k moves in the direction opposite to the main blade movement direction p. This is a technique that is known and used as a very general method not only for carpenter tools, but also for agricultural implements such as fences and axes.
[0023]
  Of the present inventionClaim 1In the lens centering machine, centrifugal force is applied to the lens holding the two bell holders while being synchronously rotated, and mechanical vibration is applied to the bell holder by the vibration applying means to cause a wedge action. The lens is centered by moving the lens in the centering direction and then centering the lens.
  In addition, the mechanical vibration oscillated by the oscillation device is adjusted in the vibration force by a pressure adjusting spring, the direction of the vibration is made constant by a parallel spring, and is transmitted to a bell holder by a vibration coupling means. Then, the state of the damping point of the resonance point of the parallel spring is output as a change in current with a piezoelectric sensor attached to the parallel spring and appears on the vibration measuring instrument, and the centripetal action ends at the lower limit of the damping curve that appears on the vibration measuring instrument. Check the point.
[0024]
  Of the present inventionClaim 2In the lens centering machine, centrifugal force is applied to the lens holding the two bell holders while being synchronously rotated, and mechanical vibration is applied to the bell holder by the vibration applying means to cause a wedge action. The lens is centered by moving the lens in the centering direction. Thereafter, the pinching force of the lens by the bell holder when the centering process is performed by the pinching force adjusting means is increased. The clamping force adjusting means also adjusts the clamping force of the lens when centering.
[0026]
  Of the present inventionClaim 3In this lens centering device, a vibration terminal is brought into contact with at least one of the bell holders that sandwich the lens, and mechanical vibration generated by the oscillation device is applied to the bell holder. The mechanical vibration is adjusted in force by a pressurizing adjustment spring, and is applied in a direction crossing the central axis of the bell holder with the direction of mechanical vibration being fixed by the holding means of the vibration terminal. The piezoelectric sensor attached to the holding means detects the state of attenuation of the resonance point of the holding means, and the vibration measuring device shows the state of attenuation detected by the piezoelectric sensor, and the lens at the lower limit of the attenuation curve appearing on the vibration measuring device. Completion of centering is detected.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
[Embodiment 1]
Embodiment 1 of the present invention is shown in FIG. 1 and FIG. FIG. 1 is a cross-sectional view showing a lens centering machine and a lens centering device, and FIG. 2 is a cross-sectional view showing in detail the periphery of an upper and lower bell holder and an upper and lower shaft.
[0028]
In FIG. 1, the lower shaft 4 of the lens centering machine is rotatably attached to a base 20 of the centering machine, and the lower shaft bell holder 3 is attached to the tip of the lower shaft bell holder 3 with respect to the rotation axis of the lower shaft 4. Are attached so that their axes (center axes) coincide with each other, and the rotation axis of both members is arranged on the same axis so that the rotation of the lower shaft 4 prevents the lower shaft bell holder 3 from rotating eccentrically.
[0029]
On the other hand, the upper shaft 5 of the centering machine is fitted and held in a column 21 erected on the base 20 so as to be movable up and down, and an upper shaft bell holder 2 is attached to the rotation axis of the upper shaft 5 at its tip. It is attached so that the axis (center axis) of the upper shaft bell holder 2 coincides, and the upper shaft 5 and the upper shaft bell holder 2 are coaxially arranged so as not to rotate eccentrically. Yes. The upper shaft bell holder 2 and the lower shaft bell holder 3 are arranged to face each other with their center axes aligned.
[0030]
The upper shaft 5, the lower shaft 4, and the vertical shaft bell holders 2 and 3 are configured as shown in FIG. On the upper shaft 5 side, an upper shaft shaft portion 5a is disposed at the center, and the upper shaft bell holder 2 is screwed to the lower end of the upper shaft shaft portion 5a. The periphery of the upper shaft shaft portion 5a is covered with an upper shaft outer tube 5b that is held by the column 21 so as to be movable up and down. The upper shaft shaft portion 5a is rotated about the rotation axis line in the upper shaft outer tube 5b via a bearing 25. It is held so that it can rotate freely. The bearing 25 is supported between the upper shaft shaft portion 5a and the upper shaft outer cylinder 5b by a stopper cover 26 fixed to the upper shaft outer cylinder 5b with a screw. The upper shaft portion 5a is screwed to come into contact with the stop cover 26 from the outside of the stop cover 26.
[0031]
As shown in FIG. 1, the upper end of the upper shaft portion 5a is connected to a shaft rotation motor 23 that rotates the upper shaft portion 5a and the upper shaft bell holder 2 together. A rack portion 28 is formed on the outer surface of the upper shaft outer cylinder 5b. The rack portion 28 meshes with a pressure pinion 22 constituting a moving mechanism as a clamping force adjusting means for moving the upper shaft 5 up and down. That is, the upper shaft shaft portion 5 a to which the upper shaft bell holder 2 is attached is moved up and down in the upper shaft pressing direction 15 together with the upper shaft outer cylinder 5 b by the rotation of the pressure pinion 22, and the pressure pinion 22 and the rack portion 28 are moved. The shaft rotation motor 23 can rotate in the upper shaft rotation direction 16 with respect to the upper shaft outer cylinder 5b even in a state in which the shafts are engaged with each other.
[0032]
On the other hand, on the lower shaft 4 side, similarly to the upper shaft 5 side, the lower shaft shaft portion 4a is disposed at the center, and the lower shaft bell holder 3 is screwed to the upper end of the lower shaft shaft portion 4a. The periphery of the lower shaft shaft portion 4a is covered with a lower shaft outer tube 4b fixed to the base 20 by a fixing means such as a bolt. The lower shaft shaft portion 4a is connected to the lower shaft outer tube 4b via a bearing 25. It is held so as to be rotatable around the rotation axis. The bearing 25 is supported between the lower shaft shaft portion 4a and the lower shaft outer cylinder 4b by a stopper cover 26 fixed to the lower shaft outer cylinder 4b with a screw. In order to prevent the locking of the stopper cover 26, a retaining ring 27 is provided. The lower shaft shaft portion 4a is screwed to be in contact with the stop cover 26 from the outside of the stop cover 26. As shown in FIG. 1, the lower end of the lower shaft portion 4a is connected to a shaft rotation motor 23 that rotates the lower shaft portion 4a and the lower shaft bell holder 3 together. That is, the lower shaft portion 4 a to which the lower shaft bell holder 3 is attached is rotatable in the lower shaft rotation direction 17 with respect to the lower shaft outer cylinder 4 b fixed to the base 20.
[0033]
On the tip side where the upper shaft bell holder 2 and the lower shaft bell holder 3 face each other, a conical recess is formed in the cylindrical end surface so that the center of the lens 1 to be processed can be centered. The tip of the ring is pointed. If the length of the cylindrical portion (thin diameter portion) on the tip side of the bell holders 2 and 3 on the vertical axis is set to be twice or more (for example, about 3 times) the diameter, mechanical vibration described later When is applied, resonance easily occurs within the elastic limit. The lens 1 to be processed is sandwiched between the vertical shaft bell holders 2 and 3 by the lowering of the upper shaft 5 by the rotation of the pressure pinion 22, and the same direction (vertical shaft rotation directions 16 and 17 by the shaft rotation motors 23 and 23. ) And the vertical axis bell holders 2 and 3 that rotate in synchronization with each other.
[0034]
The outer peripheral surface of the vertical shaft bell holders 2 and 3 constitutes a part of an excitation mechanism as a vibration applying means for applying mechanical vibration in a direction intersecting (orthogonal) with the central axis of the vertical shaft bell holders 2 and 3. The vibrating terminal 6 is free to contact. The vibration applying means, which is an excitation mechanism, includes a piezoelectric element 8 serving as an oscillating device that oscillates mechanical vibration, vibration connecting means including the vibration terminal 6 and the vibration connecting rod 7, and an additive for adjusting the mechanical vibration force. It comprises a pressure adjusting spring 9 and a parallel spring 10 that applies the vibration to the vertical shaft bell holders 2 and 3 from a certain direction.
[0035]
The axis of the vibration terminal 6 is perpendicular to the central axis of the vertical shaft bell holders 2 and 3, and the vibration terminal 6 is based on a fixed plate 12 erected on the upper surface of the vibration device main body 13 and is a pressure adjusting spring. 9, supported by the parallel spring 10 via the piezoelectric element 8 and the vibration connecting rod 7. Further, the tip of the vibration terminal 6 is formed in a U shape and is bifurcated up and down so that the upper and lower end surfaces of the bifurcated shape are in contact with the outer peripheral surfaces of the vertical shaft bell holders 2 and 3, respectively. It has become.
[0036]
The parallel spring 10 is configured such that two leaf springs are arranged in parallel to the vibration device main body 13 via a parallel spring substrate 11. A piezoelectric sensor 18 is attached to the parallel spring 10, and the piezoelectric sensor 18 detects and outputs vibrations oscillated by the piezoelectric element 8, and is sent to a vibration measuring device 19, and a control device (not shown) based on the result. ) Controls the lens centering machine.
[0037]
The vibration device main body 13 is an output screw 24 (shown as an output screw in the figure) of a vibration body driving device rotatably supported by a seat 30 fixed to the base 20. The output shaft is configured to rotate by a stepping motor (not shown) as a), and the vibration terminal 6 abuts on the vertical shaft bell holders 2 and 3 and moves in a direction 14 (vibrator attaching / detaching direction). It is free. The parallel spring substrate 11, the fixed plate 12, and the vibration device main body 13 constitute a part of the vibration mechanism.
[0038]
In addition, the lens centering device provided in the lens centering machine has a vibration terminal 6 in contact with the vertical axis bell holders 2 and 3 and mechanical vibrations on the vertical axis bell holders 2 and 3 via the vibration terminals 6. A piezoelectric element 8 as an oscillating device to be applied, a pressurizing adjustment spring 9 for adjusting the amount of vibration, and holding of the vibration terminal 6 for applying the vibration so as to intersect the central axis of the vertical axis bell holders 2 and 3 A parallel spring 10 as a means; a piezoelectric sensor 18 that is attached to the parallel spring 10 and detects attenuation of a resonance point transmitted to the parallel spring 10; and a vibration measuring device 19 that outputs a lower limit point of the attenuation curve. It comprises.
[0039]
Next, a lens centering method using the lens centering machine having the above configuration will be described.
First, the lens 1 to be processed drives the pressure pinion 22 to move the upper shaft 5 in the direction of the lower shaft 4, and the upper and lower shaft bell holders 2 and 3 are interposed between the upper shaft 5 and the lower shaft 4. Held. At this time, the upper shaft bell holder 2 and the upper shaft 5 are adjusted to a load (light load state) suitable for the lens 1 to be processed, which is experimentally determined in advance. A load is applied. Now, it can be said that the clamped processed lens 1 is not necessarily centered, like the processed lens 1, the upper shaft bell holder 2, and the lower shaft bell holder 3 shown in FIGS. 3 (a) and 3 (b). It is often in a relationship.
[0040]
Therefore, the two upper and lower shaft rotation motors 23 connected to the upper shaft shaft portion 5a and the lower shaft shaft portion 4a are synchronously rotated in the same direction (vertical shaft rotation directions 16 and 17), and the upper and lower shaft bell holders 2 and 3 are covered. While rotating the processing lens 1, the vibration device main body 13 is moved in the vibration member attaching / detaching direction 14 by the output screw 24 of the vibration member driving device, and the bifurcated tip of the vibration terminal 6 is respectively connected to the upper shaft bell holder 2 and the lower shaft bell. It is applied to each outer peripheral surface of the holder 3. The vibration terminal 6 is applied with a predetermined pressure determined experimentally so that the axis of the vibration terminal 6 and the axis (center axis) of the upper and lower shaft bell holders 2 and 3 are orthogonal to each other. The vibration is applied by 8. Then, the vibration moves to the upper shaft bell holder 2 and the lower shaft bell holder 3 to start vibration, and the lens 1 to be processed causes a wedge action between the upper and lower shaft bell holders 2 and 3, and FIG. It moves in the lens movement direction i shown in FIG.
[0041]
When the upper and lower shaft portions 5a and 4a of the upper and lower shafts 5 and 4 are rotated while continuing the vibration, the lens 1 to be processed is reduced in friction due to the rotating centrifugal action and the pressing action in the upper shaft pressing direction 15 of the upper shaft 5 is. Coupled with the centripetal action continues. In the meantime, if a current is passed through the piezoelectric sensor 18, the resonance point of the parallel spring 10 is attenuated in the process of shifting from the tilted θ ° state of FIGS. 3A and 3B to the centered state. The state of going is output as a change in current. The attenuation curve in this state appears in the vibration measuring device 19. The lower limit of the attenuation point is the end point of the centering action. After this lower limit is detected by the vibration measuring instrument 19, it is sent to a control device (not shown), and the control device instructs the end of the centering operation.
[0042]
Next, the control device drives the pressurization pinion 22 to lower the upper shaft 5 in the upper shaft pressurization direction 15 to increase (make strong) the pressure applied to the lens 1 to be processed. Centering is performed with a grindstone shaft (not shown) (see FIG. 7). In this example, the pressing force of the lens 1 to be processed between the vertical axis bell holders 2 and 3 is increased after the centering operation is finished by the control device. However, the present invention is not limited to this. When the end point is detected and the signal is sent to the control device, the pressing pinion 22 may instruct the end of the centering operation after holding the lens 1 to be processed at a high pressure.
[0043]
Here, in the configuration shown in FIG. 1, the piezoelectric element 8 is used as an oscillation device that oscillates mechanical vibration. However, the oscillation device serving as a mechanical vibration source is not limited to the piezoelectric element 8, but an ultrasonic vibrator, In general, anything that can generate mechanical vibration, such as vibration by an electromagnet, an eccentric mechanism by a motor, can be used.
[0044]
According to the present embodiment, an inefficient centering method in which a lens having a Z coefficient of 0.15 or less is performed by a clogging (cider) system in a centering process of a small-diameter lens, which is not possible with the conventional bell clamp system alone. There is no need to use the spear efficiently, and the effect of reducing the cleaning process can be obtained.
[0045]
[Embodiment 2]
A second embodiment of the present invention is shown in FIG. FIG. 5 is a sectional view showing a lens centering machine and a lens centering apparatus.
[0046]
On the base 20 of the centering machine, the vertical shaft bell holders 32 and 33 attached to the vertical shafts 35 and 34 disposed coaxially and oppositely are formed on the rack portion 46 formed on the outer periphery of the upper shaft 35. A clamping mechanism is provided so that the lens 31 to be processed can be clamped by the pressure pinion 40 meshed with each other. In the present embodiment, the shape of the vertical axis bell holders 32 and 33 of the first embodiment is changed so that the large-diameter workpiece lens 31 can be centered. The vertical shaft bell holders 32 and 33 of the shape used can be used.
[0047]
The upper shaft 35 and the lower shaft 34 are rotatably supported with respect to an upper shaft column 49 and a lower shaft column 50 that are integrally formed with the base 20, respectively. As in the first embodiment, the upper shaft 35 includes an upper shaft portion 35a and an upper shaft outer cylinder 35b. The lens 31 can be sandwiched between the lower ends of the upper shaft portion 35a by a bell clamp method. An upper shaft bell holder 32 is screwed. The upper shaft portion 35a is held in the upper shaft outer cylinder 35b via a bearing 51 so as to be rotatable about the rotation axis, and an upper shaft gear 37 is attached to the upper end of the upper shaft portion 35a. The bearing 51 is supported between the upper shaft portion 35a and the upper shaft outer tube 35b by a stop cover 52 screwed into the upper shaft outer tube 35b. It is screwed to the shaft portion 35a.
[0048]
The upper shaft outer cylinder 35 b is slidably held by the upper shaft column 49 and is movable along the rotation axis of the upper shaft 35. On the outer surface of the upper shaft outer cylinder 35b, the rack portion 46 is formed which meshes with the pressure pinion 40 constituting a moving mechanism as a clamping force adjusting means for moving the upper shaft 35 up and down. That is, the upper shaft portion 35a to which the upper shaft bell holder 32 is attached can be moved up and down together with the upper shaft outer cylinder 35b by the driving operation of the pressure pinion 40.
[0049]
On the other hand, the lower shaft 34 is held by the lower shaft column 50 so as to be rotatable about the rotation axis, and a lower shaft bell holder 33 capable of sandwiching the lens 31 to be processed by a bell clamp method is screwed to the upper end thereof. A lower shaft gear 36 is attached to the lower end of the lower shaft 34 so that the lower shaft 34 does not slide in the axial direction of the rotation axis. The members constituting the lower shaft 34 are the same as those in FIG.
[0050]
An upper shaft drive gear 44 and a lower shaft drive gear 42 are meshed with the upper shaft gear 37 of the upper shaft 35 and the lower shaft gear 36 of the lower shaft 34, respectively. The vertical drive gears 44 and 42 are interlocked by the transmission shaft 43 and are synchronously rotated in the same direction. A shaft drive motor 41 is connected to the lower end of the transmission shaft 43 via an overtaking clutch 47 so that the transmission shaft 43 and the vertical drive gears 44 and 42 can rotate in the transmission shaft rotation direction 45. Thus, the upper shaft bell holder 32 and the lower shaft bell holder 33 rotate in synchronization with the upper shaft rotation direction 39 and the lower shaft rotation direction 38.
[0051]
In addition, a high speed motor 48 arranged to face the shaft drive motor 41 is connected to the upper end of the transmission shaft 43 so that the transmission shaft 43 and the vertical shaft drive gears 44 and 42 can rotate in the transmission shaft rotation direction 45. It has become. The high-speed motor 48 is driven to idle when the transmission shaft 43 is rotated by the shaft drive motor 41. However, when the high-speed motor 48 is activated, the overtaking mechanism of the overtaking clutch 47 causes the shaft driving motor 41 to rotate. The transmission shaft 43 is rotated at a high speed, and the vertical shafts 35 and 34 and the vertical shaft bell holders 32 and 33 are rotated in the vertical shaft rotation directions 39 and 38 via the vertical shaft driving gears 44 and 42 and the vertical shaft gears 37 and 36. The lens 31 to be processed sandwiched between the vertical axis bell holders 32 and 33 is rotated at a high speed. The shaft drive motor 41 is set to rotate to the same degree as the shaft rotation motor 23 of the first embodiment.
[0052]
On the sides of the outer peripheral surfaces of the vertical shaft bell holders 32 and 33 that sandwich the lens 31 to be processed, a vibration terminal 6 that constitutes an excitation mechanism as vibration applying means that is configured in the same manner as in the first embodiment, and a vibration coupling rod. 7, the piezoelectric element 8, the pressure adjusting spring 9, the parallel spring 10, the parallel spring substrate 11, the fixing plate 12, and the vibration device main body 13 are arranged in the same manner as in the first embodiment, and the vibration terminal 6 is bifurcated. The formed tip is brought into contact with the outer peripheral surfaces of the vertical axis bell holders 32 and 33, respectively, and mechanical vibration generated by the piezoelectric element 8 can be applied in a direction perpendicular to the central axis of the vertical axis bell holders 32 and 33. Yes.
[0053]
The vibration terminal 6 is provided with a cutout portion 54 through which the transmission shaft 43 can pass so as not to interfere (abut) with the transmission shaft 43. However, the present invention is not limited to this, and the vibration terminal 6 may pass through the side of the transmission shaft 43 as long as the vibration terminal 6 and the transmission shaft 43 do not interfere with each other.
[0054]
Next, a lens centering method using the lens centering machine having the above configuration will be described.
Similar to the first embodiment, the lens 31 to be processed is sandwiched between the vertical shaft bell holders 32 and 33. Then, the shaft drive motor 41 is driven and the vertical shaft drive gears 44 and 42 are synchronously rotated by the transmission shaft 43, and through the vertical shaft gears 37 and 36 and the vertical shafts 35 and 34, as in the first embodiment. The vertical shaft bell holders 32 and 33 and the lens to be processed are rotated, and mechanical vibration is applied in a direction perpendicular to the central axes of the vertical shaft bell holders 32 and 33 by the vibration terminal 6. As a result, the lens 31 to be processed sandwiched between the vertical shaft bell holders 32 and 33 is centered by the wedge action caused by centrifugal force and vibration.
[0055]
Further, when the lens 31 to be processed sandwiched between the vertical axis bell holders 32 and 33 is difficult to move in the centripetal direction, for example, when centering the lens 31 having a large diameter, the high-speed motor 48 is driven. The lens 31 to be processed is rotated at a high speed to generate a large centrifugal force on the lens 31 to be processed. For this reason, the lens 31 to be processed that is eccentric (or inclined) with respect to the rotation axis of the bell holders 32 and 33 is moved by the centrifugal force of the lens 31 to be easily slid. Furthermore, since the vibration is imparted to the lens 31 by the vibration imparting means via the vertical shaft bell holders 32 and 33, the centering operation of the lens 31 is extremely accelerated.
[0056]
According to the present embodiment, in addition to the effects of the first embodiment, not only the centering operation of the lens 31 to be processed having a reduced diameter, but also the centering operation of the large-diameter processing lens 31 can be performed at high speed. Thus, an effect that the lens can be centered can be obtained.
[0057]
In the first and second embodiments, the case where the upper shaft bell holders 2 and 32 and the lower shaft bell holders 3 and 33 are arranged in the vertical direction has been described. Two bell holders to be sandwiched may be arranged in the horizontal direction. In this case, instead of placing the processed lenses 1 and 31 on the lower shaft bell holders 3 and 33, for example, the lens outer peripheral surface of the processed lenses 1 and 31 is sandwiched and positioned between the two bell holders. Thereafter, at least one of the bell holders may be moved and clamped.
[0058]
In this case, if a hole communicating with the space at the center of the bell holder is formed at the center of the horizontal shaft corresponding to the movable upper shaft 35a in the second embodiment, the space between the two bell holders The lens to be processed can be held while being attracted.
[0059]
Moreover, in each embodiment, although the vibration terminal 6 contact | abutted to two bell holders, you may make it contact | abut only to one side.
[0060]
Furthermore, although it was made to contact | abut so that the axis line of the vibration terminal 6 may orthogonally cross with respect to the center axis | shaft of a bell holder, it is not restricted to this, For example, about 0-60 degrees from an orthogonal axis line, the center axis | shaft of a bell holder Alternatively, the vibration terminal 6 may be configured to abut against the direction in which the axis of the vibration terminal 6 is inclined.
[0061]
The technical idea of the following configuration is derived from the specific embodiment described above.
(Appendix)
(1) In a lens centering method in which a lens as a workpiece is sandwiched between two bell holders whose center axes coincide and face each other and the lens is centered, and then the lens is centered.
While rotating the two bell holders with the lens held between them, the vibration applying means abuts on both or one of the bell holders, and mechanical vibration is applied in the direction intersecting the central axis of the bell holder by the vibration applying means. The lens centering method is characterized in that the lens centered between the bell holders is centered.
[0062]
(2) In a lens centering method in which the lens is centered by sandwiching the lens as a workpiece between two bell holders whose center axes coincide and face each other,
While rotating the two bell holders with the lens held between them, the vibration applying means abuts on both or one of the bell holders, and mechanical vibration is applied in the direction intersecting the central axis of the bell holder by the vibration applying means. And after centering the lens held between the bell holders, the holding force adjusting means increases the holding force of the lens by the bell holder, and then the lens is centered. Lens centering method.
[0063]
(3) The lens centering method according to appendix (1) or (2), wherein the bell holder can be switched to low speed rotation or high speed rotation.
[0064]
(4) In a lens centering machine that performs centering of a lens after centering the lens by sandwiching a lens as a workpiece between two bell holders whose center axes coincide and face each other,
A vibration applying means for applying mechanical vibration to both or one of the bell holders in a direction intersecting with the central axis in a state where the lens is sandwiched is provided in contact with and separated from the bell holder,
A lens centering machine characterized in that, while rotating the bell holder, the bell holder is vibrated to center the lens sandwiched between the bell holders.
[0065]
(5) In a lens centering machine that performs centering processing of a lens after centering the lens by sandwiching a lens as a workpiece between two bell holders whose center axes coincide and face each other,
With the lens being clamped, the bell holder is held between the bell holder and the vibration applying means that can come into contact with and separate from the bell holder that gives mechanical vibration to the one or both of the bell holders in a direction intersecting the central axis. Holding force adjusting means for changing the holding force of the lens,
The lens holder is centered by rotating the bell holder while applying the vibration by the vibration applying means, and then the pinching force of the lens by the bell holder is increased, and then the lens is centered. Lens centering machine.
[0066]
According to the lens centering method and apparatus of appendices (1) and (4), even if the lens to be centered has a small diameter, high-precision centering can be performed, and the centering of the lens is performed well. be able to.
[0067]
According to the lens centering method and apparatus of appendices (2) and (5), high-precision centering can be performed even when the lens to be centered has a small diameter, and the centering position of the lens at the end of centering Can be secured, and the centering of the lens can be performed satisfactorily.
[0068]
According to the lens centering method of Appendix (3), high-precision centering can be performed at high speed regardless of the diameter of the lens to be centered, and the centering of the lens can be performed satisfactorily. .
[0069]
【The invention's effect】
  As explained above, the present inventionAccording to claim 1,Even if the lens to be centered has a small diameter, high-precision centering can be performed, and the centering of the lens can be performed satisfactorily.
[0070]
  In addition, the present inventionAccording to claim 2,Even if the lens to be centered has a small diameter, high-precision centering can be performed, and the centering position of the lens can be secured at the end of centering, and the centering of the lens can be performed satisfactorily.
[0071]
  Furthermore, the present inventionAccording to claims 1 and 2,The end of centering of the lens can be reliably detected.
[0072]
  In addition, the present inventionAccording to claim 3,Even if the lens to be centered has a small diameter, high-precision centering can be performed, and a lens centering machine that can satisfactorily center the lens can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view showing the periphery of the vertical axis and the vertical axis bell holder of the lens centering machine according to the first embodiment of the present invention.
FIG. 3 is a view for explaining the centripetal action of the present invention.
FIG. 4 is a diagram for explaining the centripetal action of the present invention.
FIG. 5 is a cross-sectional view showing a second embodiment of the present invention.
6A and 6B are cross-sectional views showing a conventional centering method, in which FIG. 6A shows a state before centering, and FIG. 6B shows a state after centering.
7 shows a conventional centering device, FIG. 7 (a) is a front view, and FIG. 7 (b) is a plan view.
[Explanation of symbols]
1,31 Lens to be processed
2,32 Upper shaft bell holder
3,33 Lower shaft bell holder
4,34 Lower shaft
5,35 upper shaft
6 Vibration terminal
7 Vibration connecting rod
8 Piezoelectric elements
9 Pressure adjustment spring
10 Parallel spring
11 Parallel spring board
12 Fixed plate
13 Vibration device body
18 Piezoelectric sensor
19 Vibration measuring instrument
22, 40 Pressure pinion
23-axis rotary motor
28, 46 rack
36 Lower shaft gear
37 Upper shaft gear
41 axis drive motor
42 Lower shaft drive gear
43 Transmission shaft
44 Upper shaft drive gear
48 high-speed motor

Claims (3)

In a lens centering machine that performs centering of a lens after centering the lens by sandwiching a lens as a workpiece between two bell holders whose center axes coincide and face each other,
Comprising vibration imparting means for applying mechanical vibration in a direction intersecting the central axis of both or one of the bell holders with the lens held therebetween;
The vibration applying means includes an oscillating device that oscillates mechanical vibration, vibration coupling means that transmits the vibration to both or one of the bell holders, a pressure adjusting spring that adjusts the force of the vibration, and the vibration that the bell holder A parallel spring applied from a fixed direction to a piezoelectric sensor that is attached to the parallel spring and detects the attenuation of the resonance point of the parallel spring, and is connected to a vibration measuring instrument that outputs the lower limit of the attenuation curve. And
A lens centering machine characterized in that, while rotating the bell holder, the bell holder is vibrated to center the lens sandwiched between the bell holders. Holding force adjusting means for changing the holding force of the lens held between the bell holders,
The lens holder is centered by rotating the bell holder while applying the vibration by the vibration applying means, and then the pinching force of the lens by the bell holder is increased, and then the lens is centered. The lens centering machine according to claim 1. A lens centering device disposed in a lens centering machine that performs centering of a lens after performing centering of a lens that is a workpiece between two opposing bell holders whose center axes coincide with each other,
A vibration terminal that contacts at least one of the bell holder, an oscillation device that applies mechanical vibration to the bell holder via the vibration terminal, a pressurizing adjustment spring that adjusts the amount of vibration, and the vibration of the bell holder The vibration terminal holding means provided so as to cross the central axis of the vibration sensor, a piezoelectric sensor that is attached to the holding means and detects attenuation of a resonance point transmitted to the holding means, and outputs a lower limit point of the attenuation curve A lens centering device.

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