Step Difference Formation Data Setting Device, Eyeglass Lens Processing Device, and Step Difference Formation Data Setting Program

Abstract

To enable an operator to find that there is a portion which cannot be processed in forming a step portion of a spectacle lens, so that the operator can deal with properly.SOLUTION: A step formation data setting device 55, which sets data for forming a step portion on a rear face of a spectacle lens subjected to finish-processing, comprises: a data obtaining unit 60 that obtains data on a target step contour shape concerning the step portion; and a control unit 50 which comprises calculating means that determines whether or not a step formation processing tool can complete processing to the step contour shape, on the basis of the step contour shape and a diameter of a second processing tool unit 400 for forming the step portion, and output means that outputs a determined result by the calculating means.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a step formation data setting device for setting data for forming a step portion on the rear surface of a spectacle lens after finishing, a spectacle lens processing device including the same, and a step formation data setting program.

Background Art

[0002] Among spectacle frames, there are mainly high-curve frames with a tight frame curve (a strong degree of curvature) used for sunglasses. When fitting a prescription lens (for example, a minus-power lens with thickness at the edge) into this high-curve frame, a processing (also called step processing) for forming a step portion is enabled on the peripheral surface on the rear surface side of the lens after finishing (for example, flat processing, etc.) so as to remove the corner portion of the peripheral edge portion of the lens that interferes with the frame. A spectacle lens processing device is known (see, for example, Patent Documents 1 and 2).

[0003] In addition, among spectacle frames for sunglasses, there are lens exchange types in which the user can exchange lenses of different colors. A groove for fitting a part of the edge of the provided lens is partially formed in the rim of this lens exchange type spectacle frame. Also in this lens exchange type spectacle frame, since there is a demand for fitting a prescription lens with a thick edge, a spectacle lens processing shape acquisition device has been proposed that enables easy acquisition of the shape of a partial step portion (partial step) for fitting a spectacle lens into a partial rim (see, for example, Patent Document 3).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, when processing a stepped portion on a spectacle lens, due to restrictions on the size of the step-forming processing tool, it may not be possible to process according to the target stepped contour shape data. If the spectacle lens processing apparatus finishes processing without being able to process according to the target stepped contour shape, the operator will only notice that the processing of the spectacle lens is incomplete after fitting the spectacle lens into the rim, and no necessary countermeasures such as additional processing of the spectacle lens will be taken.

[0006] In view of the problems of the above conventional apparatus, the present disclosure aims to provide a step formation data setting apparatus, a spectacle lens processing apparatus, and a step formation data setting program that enable an operator to know that there are unprocessable parts in the formation of the stepped portion of the spectacle lens and to take appropriate countermeasures.

Means for Solving the Problems

[0007] A step formation data setting apparatus according to a first aspect of the present disclosure is a step formation data setting apparatus for setting data for forming a stepped portion on the rear surface of a spectacle lens after finish machining, comprising data acquisition means for acquiring data of a target stepped contour shape regarding the stepped portion, the stepped contour shape, the diameter of a step formation processing tool for forming the stepped portion, Based on the inclination angle of the rotating shaft to which the step-forming machining tool for holding the spectacle lens is attached with respect to the lens holding axis, with respect to the step contour shape, rotated by the rotating shaft of the inclination angle calculation means for determining whether it is possible to complete machining with the step formation processing tool, Calculation means for obtaining an elliptical locus described by the outer shape of the step-forming machining tool when viewed from the axial direction of the lens holding axis based on the inclination angle, and obtaining the locus of the machining point when the elliptical locus contacts the step contour shape for each radial angle of the spectacle lens, thereby determining whether machining can be completed by the step-forming machining tool and output means for outputting a determination result by the calculation means. Characterized by 。

[0008] A spectacle lens processing apparatus according to a second aspect of the present disclosure includes the above step formation data setting apparatus.

[0009] The step formation data setting program according to the third aspect of the present disclosure is a step formation data setting program executed by a step formation data setting device that sets data for forming a step portion by a step formation processing tool for forming a step portion on the rear surface of a spectacle lens after finishing processing. The program includes a data acquisition step of acquiring data of a target step contour shape regarding the step portion, and the step contour shape and 、 the diameter of the step formation processing tool and Based on the inclination angle of the rotating shaft to which the step-forming machining tool for holding the spectacle lens is attached with respect to the lens holding axis, with respect to the step contour shape, rotated by the rotating shaft of the inclination angle determining whether the step formation processing tool can complete the processing A calculation step for obtaining an elliptical locus described by the outer shape of the step-forming machining tool when viewed from the axial direction of the lens holding axis based on the inclination angle, and obtaining the locus of the machining point when the elliptical locus contacts the step contour shape for each radial angle of the spectacle lens, thereby determining whether machining can be completed by the step-forming machining tool an arithmetic step, and an output step of outputting the determination result by the arithmetic step, and causing a control unit of the step formation data setting device to execute them.

Advantages of the Invention

[0010] According to the present disclosure, an operator can know that there is an unprocessable portion regarding the formation of the step portion of the spectacle lens and can take appropriate measures.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Embodiments for Carrying Out the Invention

[0012] Embodiments of the spectacle lens processing apparatus, step formation data setting apparatus, and step formation data setting program according to the present disclosure will be described based on FIGS. 1 to 13.

[0013] [Overview] For example, a spectacle lens processing apparatus according to the present disclosure (for example, the spectacle lens processing apparatus 1) includes a lens holding shaft (for example, the lens chuck shaft 102). The lens holding shaft holds a spectacle lens. For example, the spectacle lens processing apparatus includes a step forming tool (for example, the step forming tool 437). The step forming tool forms a step portion on the rear surface of the spectacle lens after finishing. For example, the step forming tool is attached to a rotating shaft (for example, the rotating shaft 431). For example, the rotating shaft of the step forming tool is relatively inclined at an angle set with respect to the lens holding shaft. For example, the spectacle lens processing apparatus includes a peripheral edge processing tool (for example, the processing tool 168) for processing the peripheral edge of the spectacle lens. For example, the peripheral edge processing tool includes at least one of a rough processing tool (for example, the rough processing tool 166) and a finishing tool (for example, the normal finishing tool 164) for finishing the peripheral edge of the roughly processed lens. For example, the spectacle lens processing apparatus may include a first peripheral edge processing tool (for example, the normal finishing tool 164) having a large diameter as the peripheral edge processing tool and a second peripheral edge processing tool (for example, the end mill 435) having a smaller diameter than the first peripheral edge processing tool.

[0014] For example, the spectacle lens processing apparatus includes a moving means (for example, the moving unit 300). The moving means is configured to adjust the relative positions of the spectacle lens held by the lens holding shaft and the processing tool (for example, the processing tool 168, the step forming tool 437, etc.). For example, the spectacle lens processing apparatus includes a processing control means (for example, the control unit 50). The processing control means controls the moving means.

[0015] For example, a step forming data setting device (for example, the step forming data setting device 55) is provided in the spectacle lens processing apparatus. For example, the step forming data setting device includes a data acquisition means (for example, the data acquisition unit 60). For example, the data acquisition means acquires data on the target step contour shape regarding the step portion to be formed on the rear surface of the spectacle lens. For example, the data acquisition means acquires the outer shape data of the spectacle lens (for example, the spherical data TD).

[0016] For example, the step formation data setting device includes arithmetic means (for example, control unit 50). The arithmetic means determines whether it is possible to complete machining according to the step profile shape data with a step formation tool for the step profile shape based on the step profile shape acquired by the data acquisition means and the diameter of the step formation tool.

[0017] For example, the arithmetic means determines whether it is possible to complete machining with the step formation tool for the step profile shape based on the diameter of the step formation tool and the inclination angle (for example, inclination angle α) of the rotation axis to which the step formation tool is attached with respect to the lens holding axis. For example, the arithmetic means may determine whether it is possible to complete machining with the step formation tool by obtaining the elliptical locus described by the outer shape of the step formation tool when viewed from the axial direction of the lens holding axis, and obtaining the locus of the machining point when the elliptical locus contacts the step profile shape for each radial angle of the spectacle lens. By the arithmetic means obtaining the machining locus considering the inclination of the step formation tool, it is possible to accurately determine whether machining is possible. For example, when the arithmetic means determines that machining is impossible, it may obtain the region where machining is impossible for the step profile shape based on the elliptical locus.

[0018] Note that the inclination angle of the rotation axis may be fixed or may be arbitrarily changeable (for example, the value of the angle LSA of the display 62 is changeable). For example, when the inclination angle of the rotation axis is changed, the region machinable by the step formation tool also changes.

[0019] For example, when the arithmetic means determines that machining is impossible, for the region where machining is impossible, it obtains the locus described by the outer shape of the step formation tool when the step formation tool is positioned at a position where machining is possible with respect to the differential profile shape, and obtains the intersection of the obtained locus and the radial angle lines changed for each radial angle of the spectacle lens, thereby obtaining the machining locus planned by the step formation tool. For example, the arithmetic means obtains the elliptical locus described by the outer shape of the step formation tool when viewed from the axial direction of the lens holding axis as the locus described by the outer shape of the step formation tool. By obtaining this machining locus, the region that requires additional machining of the step portion can be made as small as possible, and the operator can efficiently perform the additional machining.

[0020] For example, the step formation data setting device includes output means (for example, control unit 50). For example, the output means outputs the determination result by the calculation means. Thereby, it is possible to notify the operator that there is a non-processable portion in the step portion of the spectacle lens, and the operator can take appropriate measures (necessary measures such as additional processing).

[0021] For example, the output means is display control means (for example, control unit 50) that controls the display of a display (for example, display 62). For example, the display control means outputs the determination result by the calculation means by displaying the non-processable area obtained by the calculation means on the display in an identifiable manner. For example, the display control means displays a first figure (for example, step contour shape figure GTSD) indicating the target step contour shape on the screen of the display, and a second figure (for example, processing locus GPP) indicating the processing area planned by the step formation processing tool with respect to the step contour shape is superimposed on the first figure to control the display of the display.

[0022] Thereby, the operator can easily visually confirm the extent of the non-processable area, and it becomes easier to perform additional processing on the unprocessed step portion that is the non-processable area. Regarding the non-processable area (unprocessed area), in order to make additional processing easier, the actual distance (for example, the distance in the left-right direction, the distance in the up-down direction) may be displayed on the display.

[0023] In addition, for example, when there is a concave portion smaller than the diameter of the first peripheral processing tool in the outer shape data, the processing control means obtains a processing locus for outer shape processing that avoids processing interference that would result in processing smaller than the outer shape based on the outer shape data and the diameter of the first peripheral processing tool, controls the moving means based on the obtained processing locus, performs a first processing of processing the spectacle lens with the first peripheral processing tool, controls the moving means based on the outer shape data for the unprocessed portion by the first processing, and performs a second processing of processing the unprocessed portion with the second peripheral processing tool. By this processing, a spectacle lens after finish processing before processing by the step formation processing tool is obtained.

[0024] Note that in the present disclosure, it is not limited to the devices described in this embodiment. For example, a control program (software) that performs the functions of the above embodiment is supplied to a system or device via a network or various storage media. Then, a control unit (e.g., a CPU, etc.) of the system or device reads and executes the program.

[0025] For example, the step formation data setting program causes the control unit of the step formation data setting device to execute a data acquisition step of acquiring data on the target step contour shape regarding the step portion, an arithmetic step of determining whether the step formation tool can complete machining the step contour shape based on the acquired step contour shape and the diameter of the step formation tool, and an output step of outputting the determination result by the arithmetic step.

[0026] 〔Example〕 One of the typical examples of the present disclosure will be described with reference to the drawings. FIG. 1 is a diagram for explaining the configuration of a machining mechanism unit included in a spectacle lens machining apparatus 1 according to the example.

[0027] For example, the spectacle lens machining apparatus 1 includes a lens holding unit 100 which is an example of lens holding means. For example, the spectacle lens machining apparatus 1 includes a lens shape measuring unit 200. For example, the spectacle lens machining apparatus 1 includes a first tool unit 150. The first tool unit 150 is configured to rotate a tool for machining the periphery of the lens LE. For example, the spectacle lens machining apparatus 1 includes a second tool unit 400. The second tool unit 400 is configured to rotate a tool for forming a step portion on the rear surface of the lens LE after finishing machining. For example, the spectacle lens machining apparatus 1 includes a moving unit 300 which is an example of moving means. The moving unit 300 is configured to change (adjust) the relative positional relationship between the lens LE and the tool held by the first tool unit 150. Also, the moving unit 300 is configured to change (adjust) the relative positional relationship between the lens LE and the tool held by the second tool unit 400.

[0028] The lens holding unit 100 includes a lens chuck shaft 102 for holding and rotating the lens LE, and a carriage 101. The lens chuck shaft 102 includes a pair of lens chuck shafts 102L and 102R. The lens chuck shaft 102L is rotatably held on the left arm 101L of the carriage 101, and the lens chuck shaft 102R is rotatably held on the right arm 101R of the carriage 101. The lens chuck shaft 102 is rotated by a motor 120.

[0029] The first tool unit 150 includes a motor 160 for rotating a tool rotation shaft 161. The tool rotation shaft 161 is rotatably held on a main body base 170 in a positional relationship parallel to the lens chuck shaft 102. A plurality of tools 168 for machining the periphery of the lens LE are attached to the tool rotation shaft 161.

[0030] For example, the tools 168 include a front bevel tool 162, a rear bevel tool 163, a normal finishing tool 164, a mirror finishing tool 165, and a roughing tool 166. In the embodiment, grindstones are used as the tools 162 to 166, but cutters may also be used. The roughing tool 166 is used for rough machining the periphery of the lens LE. The normal finishing tool 164 has a V-groove and a flat finishing surface for forming a normal small bevel on a lens LE with a low curve. The flat finishing surface of the normal finishing tool 164 is used during flat finishing. The mirror finishing tool 165 is used for further mirror-finishing the lens periphery finished by the normal finishing tool 164. The rear bevel tool 163 is used for forming a rear bevel (the bevel slope on the rear side of the lens LE) on the periphery of a lens LE with a high curve. The front bevel tool 162 is used for forming a front bevel on the periphery of a lens LE with a high curve.

[0031] In the embodiment, the axial direction of the lens chuck shaft 102 is defined as the X direction, the direction in which the axial distance between the lens chuck shaft 102 and the tool rotation shaft 16l varies is defined as the Y direction, and the direction orthogonal to the XY direction is defined as the Z direction.

[0032] In FIG. 1, a second tool unit 400 is disposed behind the carriage 101. FIG. 2 is a schematic configuration diagram of the second tool unit 400. A fixed plate 401 serving as a base of the second tool unit 400 is fixed to a support base block 172 erected on the base 170 of FIG. 1. A moving support base 404 is slidably attached to the fixed plate 401 along a rail 402 extending in the Z-axis direction. The moving support base 404 is moved in the Z-axis direction by a motor 405 rotating a ball screw 406. A rotating support base 410 is rotatably held by the moving support base 404. The rotating support base 410 is rotated about its axis by a motor 416 via a rotation transmission mechanism.

[0033] A rotating part 430 is attached to the tip of the rotating support base 410. A rotating shaft 431 orthogonal to the axial direction of the rotating support base 410 is rotatably held by the rotating part 430. The rotating shaft 431 is rotated by a motor 440 attached to the moving support base 404 via a rotation transmission mechanism disposed inside the rotating part 430 and the rotating support base 410. An end mill 435, which is an example of a hole machining tool, is coaxially attached to one end of the rotating shaft 431. Note that the end mill 435 also serves as a small-diameter finishing tool for partially cutting the periphery of the lens LE after rough machining. Further, a groove digging tool 433 is coaxially attached to the rotating shaft 431.

[0034] A step forming tool 437 for forming a step portion (step) on the rear surface side of the lens LE after finishing is coaxially attached to the other end of the rotating shaft 431. For example, the step forming tool 437 is a grindstone. The step forming tool 437 is not limited to a grindstone and may be a cutter or the like. Note that since the configuration of the second tool unit 400 can basically use the one described in Japanese Patent Application Laid-Open No. 2003-145328, details thereof are omitted.

[0035] FIG. 3 is a diagram showing an example of a step-forming cutting tool 437. The step-forming cutting tool 437 includes a first cutting surface 437a for forming a wall surface (first work surface) STa on the rear surface side of the lens LE, and a second cutting surface 437b for forming a skirt surface (second work surface) STb extending to the rear surface side of the lens LE. The second cutting surface 437b has a conical shape with a diameter decreasing toward the tip side. Also, the first cutting surface 437a has a conical shape with a diameter decreasing toward the rear end. For example, the angle SA formed by the first cutting surface 437a and the second cutting surface 437b is less than 90 degrees and is 86 degrees. Note that the cutting surface of the step-forming cutting tool 437 may be cylindrical. For example, the diameter of the step-forming cutting tool 437 is about 15 mm. Of course, the diameter of the step-forming cutting tool 437 is not limited to this, and is appropriately set according to machining performance, durability, and machining accuracy during machining of the lens LE.

[0036] The moving unit 300 is configured to adjust the relative positions of the lens LE held by the lens chuck shaft 102 and the cutting tool (cutting tool 168, step-forming cutting tool 437, etc.). In the embodiment, the moving unit 300 includes a first moving unit 310 and a second moving unit 330.

[0037] The first moving unit 310 is used to vary the axial distance between the lens chuck shaft 102, the cutting tool rotation shaft 161, and the rotation shaft 431. The second moving unit 330 is used to move the lens LE in the axial direction of the lens chuck shaft 102. Also, the moving unit 300 includes, as a third moving unit, the motors 405 and 440 of the second cutting tool unit 400.

[0038] The first moving unit 310 includes a motor 315. By the rotation of the motor 315, the moving support base 301 is moved in the X direction. Thereby, the carriage 101 and the lens chuck shaft 102 (lens LE) mounted on the moving support base 301 are moved in the X direction. Note that the configuration of the first moving unit 310 may be such that the cutting tool rotation shaft 161 and the rotation shaft 431 are moved in the X direction.

[0039] The second moving unit 330 includes a motor 335 for moving the carriage 101 (lens chuck shaft 102) in the Y direction. The carriage 101 is held by a moving support base 301 so as to be movable in the Y direction along shafts 333 and 334. The rotation of the motor 335 is transmitted to a ball screw 337 extending in the Y direction, and the rotation of the ball screw 337 moves the carriage 101 (lens chuck shaft 102 and lens LE) in the Y direction. In the embodiment, the second moving unit 330 is configured to move the lens chuck shaft 102 in the Y direction, but it may also be configured to move the tool spindle 161 and the rotating shaft 431 in the Y direction. That is, the second moving unit 330 may have a configuration that relatively changes the distance between the axes of the lens chuck shaft 102, the tool spindle 161, and the rotating shaft 431.

[0040] In FIG. 1, a lens shape measuring unit 200 is disposed above the carriage 101. The lens shape measuring unit 200 is used to measure the shape of the front surface (front refractive surface) of the lens LE and the shape of the rear surface (rear refractive surface) of the lens. The lens shape measuring unit 200 includes, for example, a measuring unit 200F for measuring the front surface shape of the lens and a measuring unit 200R for measuring the rear surface shape of the lens.

[0041] FIG. 4 is a schematic configuration diagram of the measuring unit 200F. The measuring unit 200F has a measuring element 206F that contacts the front surface of the lens. The measuring element 206F is attached to the tip of an arm 204F. The arm 204F is held by a mounting support base 201F so as to be movable in the X direction. The arm 204F is connected to a motor 216F via a rack 211F, a pinion 212F, a gear 214F, etc. When the motor 216F is driven, the arm 204F is moved in the X direction, and the measuring element 206F is pressed against the front surface of the lens LE. The pinion 212F is attached to the rotating shaft of a detector 213F (for example, an encoder). The position of the measuring element 206F moved in the X direction is detected by the detector 213F.

[0042] The configuration of the measuring unit 200R for measuring the shape of the rear surface of the lens is symmetric with that of the measuring unit 200F, so its description will be omitted. The measuring unit 200R includes a measuring element 206R that contacts the rear surface of the lens, a motor 216R that moves the measuring element 206R in the X direction, and a detector 213R that detects the moving position of the measuring element 206R in the X direction.

[0043] When measuring the lens shape, the measuring element 206F contacts the front surface of the lens, and the measuring element 206R contacts the rear surface of the lens. In this state, the lens LE is rotated by the lens holding unit 100, and the lens chuck shafts 102L and 102R are moved in the Y direction by the moving unit 300 based on the blank data, so that the lens shapes of the front surface and the rear surface of the lens corresponding to the blank are measured simultaneously. That is, the position of the edge of the front surface of the lens corresponding to the blank is measured by the measuring unit 200F, and the position of the edge of the rear surface of the lens corresponding to the blank is measured by the measuring unit 200R.

[0044] FIG. 5 is a control system block diagram related to the step formation data setting device 55 and the spectacle lens processing device 1. The spectacle lens processing device 1 includes a step formation data setting device 55. The step formation data setting device 55 includes a data acquisition unit 60. The data acquisition unit 60 may also function as a data input unit. For example, the data acquisition unit 60 includes a display 62. For example, the data acquisition unit 60 includes a data input unit 63. For example, the display 62 may have a touch panel function and may be configured to include the data input unit 63. The data acquisition unit 60 is connected to the contour reading device 30. The contour reading device 30 can be, for example, a device having a function of reading the outer shape (blank) of a demo lens (equipped lens) removed from a spectacle frame and a function of reading the shape of a stepped portion marked on the demo lens. Since the details of the contour reading device 30 can be, for example, the technology described in Japanese Patent Application Laid-Open No. 2012-185490, this is incorporated herein by reference.

[0045] The step formation data setting device 55 includes a control unit 50. The control unit 50 is connected to a data acquisition unit 60 and has a function of controlling the display of the display 62. The control unit 50 has a function of an arithmetic means for performing various calculations related to the formation of the step portion. Further, the control unit 50 has a function of an output means for outputting the calculation result. For example, the control unit 50 outputs the calculation result by controlling the display of the display 62. The data acquisition unit 60 includes a memory 70 which is an example of a storage means. Various data acquired by the data acquisition unit 10 are stored in the memory 70. Further, various programs for the control unit 50 to control the operation of the step formation data setting device 55 are stored in the memory 70.

[0046] Also, in the present embodiment, the control unit 50 also serves as the control unit of the spectacle lens processing device 1 and is configured to control the overall operation of the spectacle lens processing device 1. Electrical system components (such as motors) of each unit shown in FIGS. 1, 2, and 4 are connected to the control unit 50. The control unit 50 is configured to perform various calculations for lens processing.

[0047] Note that the step formation data setting device 55 may be separated from the spectacle lens processing device 1. In this case, for example, the step formation data setting device 55 and the control unit of the spectacle lens processing device 1 are configured to be capable of data communication.

[0048] <Operation> The operations of the step formation data setting device 55 and the spectacle lens processing device 1 having the above configuration will be described. Hereinafter, a case where a step portion is formed on the periphery of the lens LE in order to fit a prescription lens into the rim of a lens replacement type spectacle frame will be described.

[0049] <Obtaining blank mold data and step contour shape> First, an example of obtaining the blank mold (outer shape of the lens LE) of the target spectacle lens and a partial step contour shape by, for example, the contour reading device 30 will be described.

[0050] FIG. 6 is a diagram showing a typical example of an eyeglass frame SF that requires the formation of a partial step portion. FIG. 6(a) shows a front view of the eyeglass frame SF. FIG. 6(b) shows a partial cross-sectional view when the eyeglass frame SF is cut at position C. A concave groove (depression groove) G indicated by a dotted line is formed in the rim of the eyeglass frame SF. The concave groove G has a constant width FW. The depth of the concave groove G is the distance FD from the edge GC of the rim of the eyeglass frame SF. A demo lens SL is fitted into the concave groove G of the eyeglass frame SF. The demo lens SL has a constant thickness.

[0051] FIG. 6(c) is a diagram showing a front view of the demo lens SL attached to the eyeglass frame SF. In order to prevent the demo lens SL from falling when it is fitted into the concave groove G of the rim of the eyeglass frame SF, hook portions SLa of convex portions are formed at both the left and right ends of the demo lens SL.

[0052] When obtaining the spherical shape and the partial step contour shape, with the demo lens SL attached to the eyeglass frame SF, the operator marks along the inner boundary of the rim on the lens surface of the demo lens SL with a pen or clay or the like. After the operator removes the demo lens SL from the eyeglass frame SF, the contour of the demo lens SL and the marked inner boundary are read by the contour reading device 30. Then, as shown in FIG. 7, spherical shape data TD (Tr, θ) that is the outer shape of the demo lens SL and step contour shape data TSD (Sr, θ) that is the contour shape for forming a step portion on the rear surface side of the lens LE are obtained by image processing. Tr is the radial length of the spherical shape TD with respect to the spherical center FC, Sr is the radial length of the step contour shape TSD with respect to the spherical center FC, and θ is the radial angle. In FIG. 7, the region surrounded by the spherical shape data TD and the step contour shape data TSD becomes the step processing portion.

[0053] The die data TD and the target step contour data TSD read by the contour reading device 30 are input to and acquired by the data acquisition unit 10. Note that the target step contour data TSD has a two-dimensional shape similar to the die data TD, and is the shape of the step portion located on the center side with respect to the die data TD (the locus of the vertex position LT of the wall surface STa and the skirt surface STb of the step portion in FIG. 9). When the data of the die TD and the step contour shape TSD are acquired, a layout setting screen for setting the layout data of the lens LE with respect to the die data TD (the positional relationship data of the optical center of the lens LE with respect to the die) is displayed on the display 62 (omitted in the drawing). For example, a die figure based on the die data TD is displayed on the layout data setting screen. The author sets the layout data by operating a predetermined touch key displayed on the layout data setting screen. For example, examples of the layout data include the interpupillary distance (PD value) of the wearer, the distance between the frame centers of the spectacle frame F (FPD value), and the height of the optical center with respect to the geometric center of the die.

[0054] In addition, various switches for setting the processing conditions of the spectacle lens LE are displayed on the layout data setting screen. As the processing conditions, for example, the material of the lens, the type of the frame, the processing mode (engraving processing, finishing processing mode), the presence or absence of chamfering processing, the presence or absence of step processing, etc. can be set. When processing a step portion on the lens LE, the operator sets the finishing processing mode and the step processing mode.

[0055] When the step processing mode is set, by the operator operating a predetermined touch key, an editing screen for step processing is displayed on the screen of the display 62. FIG. 8 is an example of the display of the editing screen 501 for step processing.

[0056] On the editing screen 501, for example, a spherical shape graphic GTD for the right eye based on the spherical shape data TD is displayed. Also, a target step contour shape graphic GTSD based on the data of the step contour shape TSD is synthesized and displayed on the spherical shape graphic GTD. Further, at the lower left of the editing screen 501, a processed cross-sectional view GSB of the step portion in the lens LE is displayed. The operator can set the width of the step portion (the width between the front surface of the lens and the wall surface STa on the rear surface side) LSW and the angle of the skirt of the step portion (the angle with respect to the direction of the lens chuck axis 102) LSA by operating the touch keys with reference to the processed cross-sectional view GSB. For example, the width LSW of the step portion is set by measuring the thickness of the demo lens SL. Alternatively, it is set based on this width FW when the width FW of the concave groove G of the spectacle frame SF is measured. Also, the angle LSA of the skirt surface STb with respect to the X direction is arbitrarily set by the operator. For example, the angle LSA can be set in the range of 5 degrees to 15 degrees. The initial value is set to 5 degrees.

[0057] Note that the height information LSD of the step portion is obtained by the control unit 50 by calculating the difference between the radial length Tr of the spherical shape data TD and the radial length Sr of the step contour shape data TSD for each radial angle θ.

[0058] Here, the partial rim of the spectacle frame SF of the lens replacement type is designed in various shapes. On the other hand, when forming a step portion to fit the prescription lens LE into the partial rim, there may be a case where it cannot be processed according to the step contour shape data TSD due to the constraint of the size of the step forming tool 437. Therefore, the control unit 50 determines whether it is possible to complete the processing according to the step contour shape data TSD based on the step contour shape data TSD and the diameter of the step forming tool 437. In this determination, since the rotation axis 431 of the step forming tool 437 during the processing of the step portion is set to be not parallel but inclined with respect to the X direction which is the axial direction of the lens chuck axis 102, it is necessary to consider the angle of inclination of the rotation axis 431.

[0059] FIG. 9 is a diagram for explaining the positional relationship between the X direction and the rotation axis 431 and the positional relationship between the lens LE and the step-forming tool 437 when forming a stepped portion on the lens LE after finish machining. During the machining of the stepped portion, the lens LE and the step-forming tool 437 are relatively moved so that the vertex CM between the first machining surface 437a and the second machining surface 437b of the step-forming tool 437 coincides with the vertex position LT between the wall surface STa and the skirt surface STb of the stepped portion. The inclination angle α of the rotation axis 431 of the step-forming tool 437 with respect to the X direction (axial direction of the lens chuck axis 102) at this time is determined by the angle LSA of the skirt surface STb set on the editing screen 501 and the angle (omitting the sign) of the second machining surface 437b with respect to the rotation axis 431. Then, based on the inclination angle α, as shown on the right side of FIG. 9, an elliptical locus EP drawn by the vertex CM (outer shape of the step-forming tool 437) when viewed from the X direction is obtained (elliptical locus with the center MO of the rotation axis 431 as the reference). The determination of whether machining can be completed without machining interference based on the elliptical locus EP is obtained based on the elliptical locus EP, unlike the circular locus drawn by the tool 168 attached to the tool rotation axis 161 in a parallel relationship with the lens chuck axis 102.

[0060] FIG. 10 is a diagram for explaining the determination of whether machining can be completed without machining interference based on the elliptical locus EP with respect to the step profile shape data TSD shown in FIG. 7. In the machining apparatus 1 of FIG. 1, the elliptical locus EP of the step-forming tool 437 contacts the step profile shape while the lens LE rotates, but in FIG. 10, relatively, it shows the state where the elliptical locus EP contacts around the step profile shape data TSD. Note that the step profile shape data TSD is set as a range that is not machined by the step-forming tool 437 within the range of the radial angle where the spherical mold data TD is not located on the outside.

[0061] In the radial profile shape data TSD, let the radial length at the radial angle θn be Srn, the radius of the step-forming cutting tool 437 (distance from the rotation center to the apex CM) be R, the axial distance between the center of the lens chuck shaft 102 and the center MO of the elliptical locus EP be Yn, and when the inclination angle of the rotation axis 431 is α, the axial distance Yn is expressed by the following formula. Here, n changes as n = 1, 2, 3, ···, N. For example, N is 1,000 points.

[0062]

Equation

[0063] From the machining point PMa to the machining point PMc on the step profile shape data TSD, for each unit change angle of the radial angle θn (for example, when the machining points are 1,000 points, the unit change angle of the radial angle θn is 0.36 degrees), the machining points change by a minute distance.

[0064] The control unit 50 determines whether it is possible to machine according to the step profile shape data TSD without machining interference by determining whether each machining point PMi is located inside the step profile shape data TSD.

[0065] From the machining point PMa to the machining point PMc, the step profile shape data TSD is in the range of a convex shape. Basically, in the range of the convex shape, the elliptical locus EP can machine without interfering with the step profile shape data.

[0066] However, in Fig. 10, between the machining point PMc at the radial angle θc and the machining point PMd at the radial angle θd, the step profile shape data TSD is in a concave shape. If an attempt is made to position each machining point PMi on the step profile shape data TSD during this interval, it will interfere with the step profile shape data TSD of other parts, rendering machining impossible. Therefore, the interval from the machining point PMc to the machining point PMd is determined as a non-machinable region (range).

[0067] When the control unit 50 determines that there is a non-machinable region in the step profile shape data TSD, it outputs this fact. For example, the control unit 50 controls the display 62 to display a message indicating non-machinability on the editing screen 501 shown in Fig. 8. For example, in the step profile shape data TSD of Fig. 7, to draw attention to the existence of a non-machinable region near the radial angle of 180 degrees, the control unit 50 causes the display 62 to display a caution mark NMa near the radial angle of 180 degrees on the step profile shape graphic GTSD on the editing screen 501. Also, since a non-machinable region also exists near the radial angle of 0 degrees, the control unit 50 causes the display 62 to display the caution mark NMa near the radial angle of 0 degrees as well. As a result, the operator can recognize that there is a non-machinable region in the step profile shape data TSD and that machining cannot be completed by the step forming tool 437.

[0068] Furthermore, when an operator touches the caution mark NMa, a magnified screen 520 of a graphic indicating a non-machinable area pops up and is displayed on the editing screen 501 as shown in FIG. 11 to enable identification of the non-machinable area. On the magnified screen 520 in FIG. 11(a), a graphic of a machining locus GPP that is actually scheduled to be machined by the step-forming tool 437 is displayed. The machining locus GPP is displayed superimposed on the step profile shape graphic GTSD. And an area GNA between the machining locus GPP and the step profile shape graphic GTSD is shown as a non-machinable area (unmachined area). The non-machinable area GNA is displayed so as to be distinguishable from an area GSD machinable by the step-forming tool 437. For example, the area GNA is displayed in a different color from the area GSD. With such display, the operator can visually identify the non-machinable area by the step-forming tool 437. Also, the actual distance in the vertical direction (y direction) in the non-machinable area GNA is displayed in the display column 521, and the actual maximum distance in the horizontal direction (x direction) is displayed in the display column 522. With the display of these distances, the operator can recognize the range of additional machining of the lens LE and can perform additional machining more easily.

[0069] The magnified screen 520 in FIG. 11(b) is a diagram showing another display example to enable identification of the non-machinable area. In the magnified screen 520 in FIG. 11(b), the non-machinable area is displayed as a curve graphic GNL. The area from the start point to the end point of the curve graphic GNL is shown as the non-machinable area. Also with such display, the operator can visually identify the non-machinable area by the step-forming tool 437.

[0070] Here, an arithmetic method for obtaining the machining locus GPP in the non-machinable area will be described. Between the machining point PMc and the machining point PMd in FIG. 10, machining is performed by the apex CM of the step-forming tool 437 on the elliptical locus EP. Therefore, the machining points for each unit angle between the machining point PMc and the machining point PMd cannot be obtained based on the formula of Equation 1 described above. Thus, the control unit 50 obtains the machining locus GPP in the non-machinable area as follows.

[0071] FIG. 12 is a diagram for explaining a method of calculating a planned machining locus GPP by the step-forming tool 437. In FIG. 12, for the sake of simplicity of explanation, it is assumed that in the xy coordinates with the center FC of the ball mold as the origin, the center MO of the elliptical locus EP is located in the x-axis direction (the 0-degree direction of the radial angle). For example, the machining locus GPP is obtained for each radial angle of a unit change angle (in the embodiment, 0.36 degrees) with the center FC as the center. Note that the xy directions in FIG. 12 are directions for convenience of explanation and are different from the XY directions shown in FIG. 1.

[0072] In FIG. 12, the radial angle line LLP of a certain radial angle θi (i = 1, 2, 3,..., N) is represented by the following equation (2).

Equation

Equation

[0073] By solving the above simultaneous equations (2) and (3), the xy coordinates of the intersection point where the radial angle line LLP intersects the elliptical locus EP are obtained. Note that two intersection points are obtained, but the intersection point closer to the center FC is adopted as the calculation result. Then, by changing the radial angle θi for each unit change angle and obtaining the intersection points of each radial angle θi, the coordinates on the elliptical locus EP shown in FIG. 12 are obtained.

[0074] In addition, in Fig. 10, the elliptical locus EP may be in the case of the radial angle θc in contact with the machining point PMc in the step profile shape data TSD or in the case of the radial angle θd in contact with the machining point PMd in the step profile shape data TSD. Therefore, the coordinates on each elliptical locus EP are obtained. Then, in the overlapping part of the elliptical loci EP, the coordinates closer to the center FC are adopted. Thereby, the machining locus GPP is obtained in the area where machining is not possible (the area between the machining points PMc and PMd).

[0075] The machining locus GPP is obtained as described above and is displayed on the screen of the display 62, so that the difference from the non-machinable area GNA becomes visually clear, and when the operator performs additional machining, it becomes easier to grasp the additional machining area.

[0076] After the operator sets the necessary data regarding the formation of the step portion and confirms the non-machinable area using the editing screen 501, the lens LE is clamped by the lens chuck shafts 102R and 102L. When the operator presses a machining start switch (not shown), the step machining data set by the step formation data setting device 55 is output to the control unit 50, which is an example of the control unit of the spectacle lens machining apparatus 1. The control unit 50 starts operations related to machining the periphery of the lens LE.

[0077] First, the control unit 50 operates the lens shape measurement unit 200 to perform lens shape measurement. The control unit 50 acquires the position information in the X direction corresponding to the ball mold on the front refractive surface and the rear refractive surface of the lens LE. At this time, the control unit 50 acquires the curve information (tilt information) of the refractive surfaces (front refractive surface and rear refractive surface) of the lens LE from the data obtained by the lens shape measurement unit 200. For example, the curve information of the front refractive surface can be obtained mathematically by using at least four points among the front refractive surface data corresponding to the ball mold. Note that the curve information of the front refractive surface may be obtained by acquiring the position information at different distances from the lens chuck center for each radial angle in the vicinity of the position corresponding to the ball mold.

[0078] When the lens shape measurement is completed, the control unit 50 starts rough machining. Based on the spherical data TD and the layout data, the control unit 50 obtains machining control data for driving each member in order to rough-machine the lens periphery. The rough machining control data is obtained by determining the axial distance between the cutting tool rotation axis 161 and the lens chuck axis 102 (the rotation center of the lens LE) for each rotation angle of the lens LE, based on the diameter (radius) of the rough cutting tool 166 and the spherical data TD. Note that the rough machining control data is obtained as data that is larger by a fixed amount of rough machining allowance than the axial distance between the grinding wheel rotation axis 161 and the lens chuck axis 102 during finish machining.

[0079] When the rough machining control data is obtained, the control unit 50 drives the motor 315, moves the carriage 101 so that the lens LE comes to the position of the rough grinding wheel 166, and then controls the motor 150 based on the rough machining control data to perform rough machining on the periphery of the lens LE.

[0080] When the rough machining is completed, then flat machining (flat finish machining) is performed. Based on the spherical data TD and the layout data, the control unit 50 obtains flat machining control data for flat-machining the lens periphery. The flat machining control data is obtained by determining the axial distance between the cutting tool rotation axis 161 and the lens chuck axis 102 for each rotation angle of the lens LE, based on the diameter of the flat finish machining surface of the finish cutting tool 164 and the spherical data TD.

[0081] Here, as shown in FIG. 13, the spherical data TD has a hook portion SLa read from the contour of the demo lens SL, and thus there is a small recess SLb in its vicinity. If the diameter of the finishing tool 164 is larger than that of the recess SLb, the recess SLb cannot be machined according to the spherical data. Therefore, the control unit 50 obtains a corrected locus TDLb that can be machined by the finishing tool 164 based on the diameter of the finishing tool 164. Since the tool rotation axis 161 of the finishing tool 164 is in a parallel positional relationship with the lens chuck axis 102, the control unit 50 does not need to consider the inclination of the rotation axis 431 as in the case of the step-forming tool 437, and by obtaining the machining points assuming that the finishing tool 164 is a perfect circle, a corrected locus TDLb for finish machining that avoids machining interference where the machining is smaller than the spherical data TD can be obtained. In FIG. 13, the corrected locus TDLb is set at two locations, the left side portion and the right side portion. The unprocessed region by the finishing tool 164 is set as the region to be machined by the end mill 435 having a smaller diameter than the finishing tool 164.

[0082] Based on the spherical data TD and the corrected locus TDLb, the control unit 50 controls the drive of the moving unit 300 to finish-machine the peripheral edge of the lens LE with the finishing tool 164. Next, the control unit 50 controls the drive of the first moving unit 310 and also controls the drives of the motors 405 and 416 of the second tool unit 400 to machine the unprocessed region by the finishing tool 164 with the end mill 435. Thereby, the finish machining is completed.

[0083] When the finishing process of the lens LE is completed, the control unit 50 forms a stepped portion on the periphery of the lens LE after the finishing process by the step-forming tool 437. The control unit 50 obtains, for the step-forming control data in the Y direction (control data of the axial distance between the center of the lens chuck shaft 102 and the center MO of the step-forming tool 437), by obtaining the machining points for each radial angle as described above based on the step profile shape data TSD. At this time, the control unit 50 sets the inclination of the rotation axis 431 of the step-forming tool 437 based on the angle LSA set by the editing screen 501. Also, the control unit 50 obtains, for each radial angle, the X-direction position corresponding to the step profile shape data TSD for the step-forming control data in the X-axis direction based on the pre-refracting surface shape of the lens LE and the width LSW of the stepped portion set by the editing screen 501. The pre-refracting surface shape of the lens LE is obtained based on the measurement result by the lens shape measurement unit 200.

[0084] Based on the control data in the Y direction and the X direction, the control unit 50 controls the driving of each motor of the moving unit 300 and the second tool unit 400, and rotates the lens LE while matching the apex CM of the step-forming tool 437 and the apex position LT of the lens LE for each radial angle as shown in FIG. 9, thereby forming a stepped portion on the lens LE. At this time, the control unit 50 completes the machining leaving an unmachinable area (area GNA in FIG. 11(a)) so that the machining point of the apex CM does not enter the center side from the step profile shape data TSD.

[0085] When the processing of the lens LE by the spectacle lens processing apparatus 1 is completed, the operator removes the lens LE from the lens chuck shaft 102. The operator uses an apparatus different from the spectacle lens processing apparatus 1 (for example, a hand grinder for engraving) to perform additional processing on the unprocessed region of the stepped portion. For example, when performing additional processing, the operator operates the display 62 of the spectacle lens processing apparatus 1 to display the enlarged screen 520 shown in FIG. 11(a). By referring to the non-processable region GNA displayed on the enlarged screen 520, the vertical distance displayed in the display column 521, the horizontal distance displayed in the display column 522, etc., it becomes easier for the operator to perform additional processing on the unprocessed region.

[0086] <Modification example> In the above description, an example of using the stepped portion forming tool 437 as the tool for forming the stepped portion (step) has been described, but the present invention is not limited to this. For example, as the tool for forming the stepped portion, the groove digging tool 433 may be used in combination. Even when the groove digging tool 433 is used as the tool for forming the stepped portion, since the processing is performed with the rotation axis 431 inclined with respect to the lens chuck shaft 102, the locus drawn by the apex of the groove digging tool 433 is an elliptical locus. Therefore, the determination as to whether the processing can be completed according to the stepped contour shape data TSD is performed based on the elliptical locus, similarly to the stepped portion forming tool 437.

[0087] In the embodiment, the inclination angle α of the rotation axis 431 of the stepped portion forming tool 437 with respect to the axial direction of the lens chuck shaft 102 is set by rotating the rotating portion 430 of the second tool unit 400, but the present invention is not limited to this. For example, the rotation axis 431 may be placed at the processing position by another turning mechanism, and the inclination angle α of the rotation axis 431 may be set indirectly by setting the turning angle.

[0088] In the above description, the case of performing flat finishing (flat processing) as the finishing process has been described as an example, but the present invention is not limited thereto. For example, as the finishing process, grooving processing using the V-groove of the finishing tool 164 may be performed. Further, as the finishing process, chamfering processing of the groove may be performed on the periphery after flat finishing using the groove digging tool 433.

[0089] As described above, typical embodiments of the present disclosure have been described. However, the present disclosure is not limited to the embodiments shown herein, and various modifications are possible within the scope of the same technical idea of the present disclosure.

Explanation of Reference Numerals

[0090] 1 Eyeglass lens processing apparatus 50 Control unit 55 Step formation data setting device 60 Data acquisition unit 62 Display 102 Lens chuck shaft 431 Rotating shaft 437 Step formation tool

Claims

1. A step formation data setting device for setting data for forming a step portion on the rear surface of a spectacle lens after finishing processing, data acquisition means for acquiring data on a target step contour shape regarding the step portion; calculation means for determining whether the step contour shape can be processed by the step formation tool rotated about the rotation axis at the inclination angle, based on the step contour shape, the diameter of the step formation tool for forming the step portion, and the inclination angle of the rotation axis to which the step formation tool is attached with respect to the lens holding axis of the spectacle lens. The elliptical locus drawn by the outer shape of the step formation tool when viewed from the axial direction of the lens holding axis is obtained based on the inclination angle, and the locus of the machining point when the elliptical locus contacts the step contour shape is obtained for each radial angle of the spectacle lens, thereby determining whether the step formation tool can complete the processing; output means for outputting the determination result by the calculation means; A step formation data setting device, characterized by comprising the above.

2. In the step formation data setting device according to Claim 1, the output means is display control means for controlling the display of a display, and the display control means outputs the determination result by the calculation means by displaying on the display an area where processing is impossible with respect to the step contour shape in an identifiable manner. A step formation data setting device characterized by this.

3. In the step formation data setting device according to Claim 2, the display control means displays a first figure showing the step contour shape on the screen of the display, and overlays and displays a second figure showing the processing area planned by the step formation tool with respect to the step contour shape on the first figure, thereby making it possible to identify an area where processing is impossible with respect to the step contour shape. A step formation data setting device characterized by this.

4. In the step formation data setting device according to any one of Claims 1 to 3, when the calculation means determines that processing is impossible, regarding the area where processing is impossible, it obtains the locus drawn by the outer shape of the step formation tool when the step formation tool is positioned at a position where processing is possible with respect to the step contour shape, and obtains the intersection points of the obtained locus and the radial angle lines changed for each radial angle of the spectacle lens, thereby obtaining the processing locus planned by the step formation tool. A step formation data setting device characterized by this.

5. An eyeglass lens processing apparatus for processing the periphery of an eyeglass lens, An eyeglass lens processing apparatus comprising the step formation data setting apparatus according to any one of claims 1 to 4.

6. A step formation data setting program executed by a step formation data setting apparatus for setting data for forming a step portion by a step formation processing tool for forming a step portion on the rear surface of an eyeglass lens after finishing processing, A data acquisition step of acquiring data of a target step contour shape regarding the step portion, Based on the step contour shape, the diameter of the step formation processing tool, and the inclination angle of the rotation axis to which the step formation processing tool is attached with respect to the lens holding axis for holding the eyeglass lens, an arithmetic step of determining whether it is possible to complete processing by the step formation processing tool rotated about the rotation axis of the inclination angle with respect to the step contour shape, wherein an elliptical locus drawn by the outer shape of the step formation processing tool when viewed from the axial direction of the lens holding axis is obtained based on the inclination angle, and a locus of a processing point when the elliptical locus contacts the step contour shape is obtained for each radial angle of the eyeglass lens, thereby determining whether it is possible to complete processing by the step formation processing tool, An output step of outputting the determination result by the arithmetic step, A step formation data setting program characterized by causing a control unit of the step formation data setting apparatus to execute the program.

Images