JPH1142599A - Side pressure cutter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance durability of a side pressure transmitting member and a pressure seal member constituting inside a pressure vessel, so that an optical element material or the like of high weight accuracy and high quality can be always obtained. SOLUTION: In the halfway of a booster line 11 of this side pressure cutter device, a pressure gage 15 which is an element converting pressure behavior into voltage and an analog monitor 16 receiving a detection signal from the pressure gage 15 to be able to set an arbitrary sampling time are provided and, pressure behavior in a pressure vessel 10 is displayed in the analog monitor 16 as a time series change of voltage and by checking pressure behavior at the time of rising pressure or during holding a set pressure, estimation of damage in a side pressure transmitting cylinder 3 or estimation of wearing in a pressure seal member 5 is estimated by a change of waveform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for cutting a workpiece by lateral pressure, and is applied to a field where a high-quality cut surface is required and cutting of the workpiece suitable for mass production is required. The present invention relates to a side pressure cutting device used in a step of cutting a workpiece, for example, a rod-shaped long glass, which is used when a glass optical element such as a glass optical element is formed by pressing.

[0002]

2. Description of the Related Art Conventionally, mass-production techniques for aspherical glass lenses by a molding method suitable for mass production of aspherical glass lenses have been established and are up to the present day. Most of the optical element materials used in molding such glass lenses have a polished, ball or polished cylindrical shape.

[0003] As a method of processing the cylindrical optical element material, a rod material is cut and polished, wrapped, and polished to obtain an optical element material having mirror-finished ends. In recent years, a new processing method utilizing material destruction due to lateral pressure has been proposed.

[0004] This new machining method does not generate chips or noise during machining, requires little machining time and little machining energy, and the side pressure during machining is not related to the size of the workpiece. Constant value, and the cut surface becomes smoother, especially for glass and ceramics.
It has many advantages not found in conventional processing methods.

[0005] The structure of a device using the conventional lateral pressure cutting method is as follows.
As shown in FIG. 5, a first metal member 6 and a second metal member 7 are provided to prevent direct contact between the workpiece 1 and the pressure seal member 5 and to prevent the pressure seal member 5 from being damaged. A so-called stopper ring system using the same is used (see Japanese Patent Application Laid-Open No. Hei 7-132500).

In the stopper ring system, a plurality of pressure sealing members 5 are applied while deforming a pair of pressure sealing members 5 by applying a tensile force in an axial direction on a rod-shaped workpiece 1 and a pressing force in a radial direction on the workpiece 1. This is a method of cutting, and each pressure seal member 5 has a structure in which it is fitted in a state of being surrounded by a step portion of each metal member 6, 7 so as not to directly contact the workpiece 1.

As shown in FIG. 5, the side pressure cutting device includes a pressure vessel 10 connected to a pressure increasing line 11, a pair of metal members 6 and 7 provided in the pressure vessel 10, and A pair of pressure seal members 5 provided at both ends of the side pressure transmitting cylinder 3 having a length, a hydraulic pump 14 for supplying a working oil 18 into a pressure chamber 9 between the pair of pressure seal members 5 from the pressure increasing holes, Pressure generator 12 incorporating pump 14 and intensifier 13
And a holding member 8 in contact with one side of the second metal member 7.

A bar-shaped workpiece 1 is provided with a streak 2 in advance, and a portion of the streak 2 of the workpiece 1 is inserted up to a position facing a boosting line 11 in a side pressure transmission cylinder 3 of a pressure vessel 10. Is done. When the hydraulic oil 18 is introduced from the pressure generating device 12 into the pressure vessel 10 through the pressure raising line 11, a compressive stress is generated on the outer peripheral surface of the workpiece 1 through the side pressure transmission cylinder 3, and A tensile stress is generated in the portion. The tensile stress generated inside the workpiece 1 increases in proportion to the pressing force,
When the tensile stress exceeds the tensile strength of the workpiece 1, the workpiece 1 is broken and cut at that point. At this time, the striations 2 located in the side pressure transmission cylinder 3 are cut almost at the same time, though there is a time difference. Work 1
The pressure medium 4 is filled between the and the side pressure transmission cylinder 3 so that the side pressure 17 is evenly applied to the entire outer periphery of the workpiece 1.

[0009]

The above-described disking method in which the pressure is increased and reduced is applied to maintain the airtightness by repeatedly expanding and contracting the rod-shaped workpiece 1 in the radial or axial direction. The side pressure transmitting cylinder 3 and the pressure seal member 5 are deteriorated.

[0010] A pressure seal member 5 which has been repeatedly pressurized and depressurized
When observing the damage occurrence state, as shown in the explanatory view of FIG. 6, the pressure seal member 5 is sandwiched by the axial clearance between the inner wall of the hole of the main body of the pressure vessel 10 and each of the metal members 6 and 7. The generated wear flaws 20 and the wear flaws 21 generated by the clearance between the first metal member 6 and the second metal member 7 and the inner circumferential direction between the side pressure transmission cylinder 3 remain, and the side pressure transmission cylinder 3, groove-shaped scratches generated in the inner circumferential direction at the same interval as the cutting interval of the optical element material that is a cut workpiece, and the cutting edge when the element material is discharged from the pressure vessel 10, A lot of scratches that are thought to have been scraped remain.

The degree of deterioration of the side pressure transmission cylinder 3 and the pressure seal member 5 cannot be confirmed in a state in which the side pressure transmission cylinder 3 and the pressure seal member 5 are incorporated in the pressure vessel 10. Has to be disassembled or removed, and has to be confirmed visually by the operator.

Further, even if a crack is generated on the inner wall of the side pressure transmission cylinder 3 or the wear of the pressure seal member 5 is progressing during the continuous cutting, the side pressure cutting device repeats the cutting under the same cutting conditions. Poor cutting of the object 1 or deterioration of the quality of the processed optical element material occur, which has been a problem in mass production.

Further, when the side pressure transmitting cylinder 3 or the pressure seal member 5 is damaged during mass production, it is not clear which member was damaged due to the deterioration of the member.
10 had to be disassembled, and a procedure of replacing both parts with new ones was required, which was a great hindrance to improving mass productivity.

The present invention solves the problems of the conventional cutting technique. In the disking method, the durability of a side pressure transmission cylinder and a pressure sealing member constituting the inside of a pressure vessel is increased, and the weight is reduced with respect to continuous cutting. An object of the present invention is to provide a side pressure cutting device that can always obtain a high-precision, high-quality optical element material or the like.

[0015]

In order to achieve the above object, a lateral pressure cutting device according to the present invention comprises means for measuring a dynamic pressure behavior in a pressure vessel, and further finely adjusts the pressure behavior. Means.

As described above, in the disking method, it is possible to display a change in pressure in the pressure vessel as a time-series change in voltage, and reproduce a cutting process most suitable for cutting a rod-shaped workpiece according to the number of times of pressure increase. This makes it possible to always obtain a high-precision, high-quality material even when processing the optical element material.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A side pressure cutting device according to claim 1 of the present invention includes a side pressure transmitting cylinder that covers the outer peripheral surface of a workpiece made of a brittle material having a rod shape and having a streak formed on the outer peripheral surface; A pressure seal member disposed around the workpiece at both ends of the side pressure transmission cylinder, a metal member for holding the pressure seal member, and pressurizing the pressure seal member via the metal member Pressurizing means for deforming,
The side pressure transmission cylinder, the pressure seal member, the metal member, and a pressure container that houses a pressurizing means, and the pressure seal member is pressurized and deformed by the pressurizing means. A side pressure cutting device for applying a side pressure to a mark to cut the workpiece by stress, further comprising means for measuring a pressure behavior in the pressure vessel.

According to a second aspect of the present invention, there is provided the lateral pressure cutting device according to the first aspect, wherein the means for measuring the pressure behavior is capable of converting a pressure change in the pressure vessel into a voltage. Is characterized in that it is possible to display a time-series change of

According to these configurations, the pressure behavior in the pressure vessel can be displayed as a time-series change in voltage, and by examining the pressure behavior at the time of increasing the pressure or maintaining the set pressure,
It is possible to predict the damage prediction of the side pressure transmission cylinder or the wear prediction of the pressure seal member based on the pressure increasing behavior.

A side pressure cutting device according to a third aspect of the present invention is a side pressure transmitting cylinder that covers the outer peripheral surface of a workpiece made of a brittle material that is rod-shaped and has a streak formed on the outer peripheral surface, and both of the side pressure transmitting cylinders A pressure seal member disposed around the workpiece at the end, a metal member for holding the pressure seal member, and pressurizing means for pressurizing and deforming the pressure seal member via the metal member And a pressure vessel containing the side pressure transmission cylinder, the pressure seal member, the metal member, and a pressurizing means, and the workpiece is pressurized and deformed by the pressurizing means. A lateral pressure cutting device that stress-cuts the workpiece by applying a lateral pressure to the streak of the pressure vessel, comprising a means for measuring a pressure behavior in the pressure vessel, and a means for finely adjusting the pressure behavior. Feature To.

According to a fourth aspect of the present invention, in the lateral pressure cutting device according to the third aspect, history management for each number of times of stress cutting is performed while measuring the pressure behavior in the pressure vessel,
It is characterized in that it is possible to reproduce a cutting process most suitable for cutting a bar-shaped workpiece according to the number of times of the stress cutting.

According to these configurations, the history management for each number of times of stress cutting is performed while measuring the pressure behavior in the pressure vessel, so that the cutting process most suitable for cutting the bar-shaped workpiece is reproduced as necessary. Therefore, even when processing the optical element material, it is possible to always obtain a high-quality material with high weight accuracy and improve the overall yield.

An embodiment of the lateral pressure cutting device of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram of a side pressure cutting device for explaining a first embodiment of the present invention, FIG. 2 (a) is a cross-sectional view of a pressure vessel portion of FIG. 1, and FIG. 2 (b) is FIG. FIG. 7 is an enlarged cross-sectional view of a metal member portion of FIG. 7A. Members corresponding to members described with reference to FIGS. 5 and 6 are denoted by the same reference numerals, and detailed description is omitted.

This side pressure cutting device is used for cutting the bar-shaped workpiece 1. With this side pressure cutting device,
Prior to cutting the workpiece 1, an indenter (not shown) previously positioned on the cutting position on the outer peripheral surface of the workpiece 1 is used to cut the outer periphery of the cutting position of the workpiece 1 prior to the cutting. Streaks 2 must be provided on the surface to easily induce cutting. The streak 2 is a plurality of notches provided in advance on the outer peripheral surface of the workpiece 1 to designate a cut surface, and the streak 2 is formed on the outer peripheral surface of the workpiece 1 at an angle perpendicular to the length direction. And is provided locally for each set distance.

The work 1 is fitted into the side pressure transmission tube 3 via the pressure medium 4, and the interval between the work 1 and the side pressure transmission tube 3 is set to several tens μm. Pressure seal members 5 are respectively disposed at both ends of the side pressure transmission cylinder 3, and are fitted into the first metal member 6 and the second metal member 7, respectively. In order to increase the airtightness at the time of increasing the pressure, the holding member 8 is moved toward the first metal member 6 by a predetermined distance by the pressing force of the hydraulic pump 14, so that each of the pressure seal members 5 is deformed under pressure.

The pressure sealing member 5 is arranged to seal the pressure that is to be released in the axial direction and the pressure that is to be released in the radial direction of the rod-shaped workpiece 1. In such a state, the outer peripheral surface of the side pressure transmission cylinder 3 and the inner peripheral part of the pressure vessel 10 in a section sandwiched by the pair of pressure seal members 5 fitted via the first metal member 6 and the second metal member 7. Is sealed to form a pressure chamber 9. Then, by flowing the working oil 18 from the pressure (oil pressure) generating device 12 into the pressure chamber 9 of the pressure vessel 10 via the pressure raising line 11, a uniform lateral pressure 17 can be applied to the outer peripheral surface of the workpiece 1.

Pressure generator 12 for applying lateral pressure 17
As shown in FIG. 1, the hydraulic pump 14 includes a hydraulic pump 14 and a pressure intensifier 13. The hydraulic pump 14 generates a force for holding the holding member 8 in the pressure vessel 10. Further, it has a function as a prime mover of the pressure intensifier 13.

As a means for measuring the pressure behavior in the pressure vessel 10, a pressure gauge 15 which is an element for converting the pressure behavior into a voltage is provided in the middle of the boosting line 11, and as a means for displaying a time-series change of the voltage. In addition, an analog monitor 16 capable of receiving a detection signal from the pressure gauge 15 and setting an arbitrary sampling time is provided.

Hereinafter, specific conditions in the side pressure cutting device of the first embodiment will be described.

The workpiece 1 of this example has a Young's modulus of 8.2 × 10 ³ kgf /
This is a solid cylindrical optical glass rod of mm ^{2 with} an outer diameter of about 11 mm, which is used for lens molding. A streak 2 for designating a cut surface on the workpiece 1 is stamped by an indenter (not shown). In the workpiece 1 used in this example, a load of 1000 g or less was applied at equal intervals of 3 mm in the axial direction on the outer peripheral surface of the workpiece 1, and eight streaks 2 were provided. The length of the streak 2 is 400 μm
And all have the same shape.

As shown in FIG. 2, a workpiece 1 having a streak 2 is fitted into a hollow cylinder-shaped side pressure transmission cylinder 3 made of methacrylic resin. A known high-viscosity oil or fat was used as the pressure medium 4 sealed between the workpiece 1 and the side pressure transmission cylinder 3. The Young's modulus of the methacrylic resin that is the material of the side pressure transmission cylinder 3 is 3.1 kgf
a / mm ^2. The length of the side pressure transmission cylinder 3 is about 20 mm, and the pressure seal member 5 is a ring-shaped rubber having a wire diameter of 1.2 mm.
The first metal member 6 and the second metal member 7 are respectively fitted to predetermined positions.

When the holding member 8 receives the pressure of the hydraulic pump 14 and moves about 1 mm toward the first metal member 6 and presses against the second metal member 7, each pressure seal member 5 is compressed and deformed. Thus, the airtightness in the pressure chamber 9 is increased. Carbon tool steel was used as the material of the first metal member 6 and the second metal member 7. The clearance accuracy of the inner diameter between the workpiece 1 and the first metal member 6 or the second metal member 7 is finished so as to be substantially the same as the clearance accuracy of the side pressure transmission cylinder 3.

The lateral pressure cutting device having the above-described configuration is operated by applying the lateral pressure 17 to 8.5 k.
The operation was performed under cutting conditions of gf / mm ² , a boosting time of 5 sec., and a set holding time of 3 sec.
In the second time, 210 times in the second time, 162 times in the third time, the airtightness of the pressure chamber 9 cannot be maintained, or it becomes impossible to cut a specified number of optical element materials,
Moreover, even if it cut | disconnected, the quality of the cut surface fell sharply.

The situation when the airtightness could not be maintained as described above, and the broken state of the consumable member observed by disassembling the inside of the pressure vessel 10 at that time were as follows. That is, it is impossible to increase the pressure to the set pressure in the first time, and the pressure seal member 5 is greatly worn. One end face was missing, and the pressure gradually decreased for the third time while maintaining the set pressure, and cracks were generated in the length direction of the side pressure transmission cylinder 3.

Therefore, in the present embodiment, as described above, the pressure gauge 15 is attached to an arbitrary position inside the booster line 11, and the analog monitor 16 that records and reproduces a voltage change converted from the pressure gauge 15 is used. Sampling time 400
When the pressure behavior of 0 and the cycle of 2 ms is expressed as a waveform, the pressure rise behavior immediately before the time when the airtightness cannot be maintained or the time when the airtightness cannot be maintained in three consecutive examinations is compared with the ideal waveform for cutting. It was found that the waveform was greatly different, and that the waveform of the consumable member every three consecutive examinations in which the consumable member was damaged also changed differently for each type of damage.

In addition, since the state of deterioration of the consumable member can be checked based on the pressure waveform of the analog monitor 16 without disassembling the inside of the pressure vessel 10, it is easy to grasp the replacement time and identify breakage during mass production. The optical element material obtained by the cutting process was at a level having no problem in quality.

FIG. 3 shows an optical element formed by subjecting the optical element material obtained by the lateral pressure cutting according to the present embodiment to post-processing such as heating, pressing and cooling.
FIG. 22 shows an explanatory view of a processing step 22. The optical element 22 of this example is
It is used as one of the lenses for a video movie, and although not shown in detail, one side is an aspherical surface and the opposite surface is a spherically bilateral convex shape. Further, the transfer surfaces of the first molding die 23 and the second molding die 24 used in the molding are each processed into a desired concave shape, and are respectively fitted to the upper and lower inner diameter portions of the body die 25. . The transfer accuracy of the optical element 22 obtained through the molding step was not different from that obtained when an optical element material having another shape was molded, and was a performance having no problem in optical characteristics.

In the first embodiment, the side pressure transmitting cylinder 3 may be any one of injection-molded and cut products, and can be used regardless of the material of the workpiece 1 to be cut. The same effect can be obtained by using a material having a Young's modulus on the order of methacrylic resin as the material of the transmission tube 3. Further, the value of the lateral pressure, the pressure increasing time, or the lateral pressure setting holding time is appropriately selected and set in accordance with the change of the processing target or the like, and the operation is performed.

The pressure gauge 15 and the analog monitor 16
As long as it has the function described above, other similar means can be adopted.

As described above, according to the lateral pressure cutting device of the first embodiment, the pressure behavior in the pressure vessel can be displayed as a time-series change of the voltage. Accordingly, it is possible to predict the damage prediction of the side pressure transmission cylinder or the wear prediction of the pressure seal member by the change in the waveform.

FIG. 4 is an overall configuration diagram of a side pressure cutting device for explaining a second embodiment of the present invention. Members corresponding to those described with reference to FIGS. A detailed description is omitted here. The configuration of the lateral pressure cutting device according to the second embodiment is basically the same as the configuration of the lateral pressure cutting device according to the first embodiment.
In that fine adjustment means 30 that enables fine adjustment of the side pressure 17 in the pressure intensifier 13 is provided.

Hereinafter, specific conditions in the side pressure cutting device according to the second embodiment will be described.

The work 1 used for the study had a Young's modulus of 8.2.
A solid cylindrical optical glass rod of × 10 ³ kgf / mm ² and an outer diameter of about 11 mm, which is exactly the same as that used in the first embodiment, and further provided on the outer peripheral surface of the workpiece 1. The striations 2 have the same shape.

In the same manner as described in the description of the first embodiment, continuous cutting of the workpiece was studied (three times) under cutting conditions considered to be currently optimal. These three
Investigating the quality of the optical element material that was cut every 25 times, including two consecutive studies in addition to the two studies,
When comparing the initial use of 1 to 25 times according to the number of times of boosting, the middle use of 101 to 125 times, and the final use of 151 to 175 times (up to the last number of cuts if there is no durability up to 175 times) It is clear from five consecutive examinations that the quality of the same material is obtained stably during the above-mentioned medium-term use, and that the quality is somewhat lower at the initial use and at the end of use than during the medium-term use. Became.

Using the analog monitor 16, the waveform at the time of cutting was recorded and reproduced, and the pressure fluctuation within the set pressure holding time was analyzed in detail. It was found that the pressure fluctuation at the time was different from the pressure fluctuation at the time of medium-term use. It was also found that the ideal pressure fluctuation of the cutting for the workpiece 1 was particularly similar to the fluctuation during the middle use.

By making the pressure distribution in the cutting step approximate to that in the middle-term use, that is, by finely adjusting the set pressure by using the fine adjustment means 30 that makes it possible to finely adjust the lateral pressure 17, the optical cut can be made. It is possible to suppress the deterioration of the quality of the element material, and the airtightness of the pressure chamber 9 is always continuous.
It could be kept up to about 300 times.

In the second embodiment, it is possible to perform the cutting by changing the boosting time or the side pressure setting holding time, and an electromagnetic valve is used as the fine adjustment means 30 for setting the side pressure 17. The adjustment can be made either manually or automatically.

As described above, according to the side pressure cutting device of the second embodiment, the history management for each number of times of stress cutting is performed while measuring the pressure behavior in the pressure vessel, and the cutting process most suitable for cutting the rod-shaped workpiece is performed. Can be reproduced, so that even if continuous cutting is performed on the optical element material, a high-quality one with high weight accuracy can always be obtained, and the overall yield can be improved.

[0050]

As described above, according to the lateral pressure cutting device of the present invention, unnecessary cutting time and energy are not required when cutting, and unnecessary time and energy are unnecessary, and one lateral pressure is applied. Only the specified multiple cutting is performed securely, and the pressure behavior in the pressure vessel is measured, and the measurement results are used to select and set appropriate various conditions, thereby transmitting the lateral pressure. It is possible to estimate the damage prediction of the cylinder or the wear prediction of the pressure seal member. Further, for example, it is possible to always obtain a high-quality, high-quality one with high weight accuracy by using it for continuous cutting of the optical element material. Therefore, effects such as improvement in overall yield can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a side pressure cutting device for explaining a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the apparatus of FIG.

FIG. 3 is an explanatory diagram of a process of manufacturing an optical element using an optical element material obtained by lateral pressure cutting in the embodiment.

FIG. 4 is an overall configuration diagram of a side pressure cutting device for explaining a second embodiment of the present invention.

FIG. 5 is an overall configuration diagram of a conventional side pressure cutting device.

FIG. 6 is an explanatory diagram of a state of occurrence of damage in a conventional lateral pressure cutting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Workpiece, 2 ... Streak, 3 ... Side pressure transmission cylinder, 4 ... Pressure medium, 5 ... Pressure seal member, 6 ... 1st metal member, 7 ... 2nd metal member, 8 ... Holding member, 9 ... Pressure chamber, 10… Pressure vessel, 11… Pressure line, 12… Pressure generator, 13… Intensifier, 14… Hydraulic pump, 15… Pressure gauge, 16… Analog monitor, 17… Side pressure, 18…
Hydraulic oil, 22… Optical element, 30… Fine adjustment means.

Claims (4)

[Claims] 1. A side pressure transmission cylinder that covers the outer peripheral surface of a workpiece made of a brittle material that is rod-shaped and has a streak formed on the outer peripheral surface, and is disposed around the workpiece at both ends of the side pressure transmission cylinder. Pressure seal member, a metal member for holding the pressure seal member, pressurizing means for pressurizing and deforming the pressure seal member via the metal member, the side pressure transmission cylinder and the pressure A pressure vessel configured to house a seal member, the metal member, and a pressurizing unit, wherein a side pressure is applied to the striation of the workpiece in a state where the pressure seal member is pressurized and deformed by the pressurizing unit. Thus, in the side pressure cutting device for stress cutting the workpiece,
A side pressure cutting device comprising means for measuring a pressure behavior in the pressure vessel. 2. The method according to claim 1, wherein the means for measuring the pressure behavior is capable of converting a pressure change in the pressure vessel into a voltage, and displaying a time-series change of the voltage. 2. The side pressure cutting device according to 1. 3. A side pressure transmitting cylinder for covering the outer peripheral surface of a workpiece made of a brittle material having a rod-like shape and having a streak formed on the outer peripheral surface, and disposed around the workpiece at both ends of the side pressure transmitting cylinder. Pressure seal member, a metal member for holding the pressure seal member, pressurizing means for pressurizing and deforming the pressure seal member via the metal member, the side pressure transmission cylinder and the pressure A pressure vessel configured to house a seal member, the metal member, and a pressurizing unit, wherein a side pressure is applied to the striation of the workpiece in a state where the pressure seal member is pressurized and deformed by the pressurizing unit. Thus, in the side pressure cutting device for stress cutting the workpiece,
A side pressure cutting device comprising: means for measuring a pressure behavior in the pressure vessel; and means for finely adjusting the pressure behavior. 4. It is possible to perform history management for each number of times of stress cutting while measuring the pressure behavior in the pressure vessel, and reproduce a cutting process most suitable for cutting the rod-shaped workpiece for each number of times of stress cutting. The side pressure cutting device according to claim 3, wherein the device is capable of being cut.