Eyeglass lens processing equipment

Abstract

To provide a spectacle lens processing device which can determine defects in a processing tool with good efficiency, and further, can satisfactorily determine defects in the processing tool.SOLUTION: A spectacle lens processing device, which processes a spectacle lens by a processing tool by relatively changing a positional relationship between the spectacle lens and the processing tool, comprises: first acquisition means which acquires a prediction value of a processing load predicted to be applied to the processing tool when processing the spectacle lens by the processing tool before processing the spectacle lens by the processing tool; second acquisition means which acquires an actually measured value of an actual processing load applied to the processing tool when actually processing the spectacle lens by the processing tool; comparison information acquisition means which acquires comparison information that enables comparison between the acquired processing load prediction value and actually measured value; and output means which outputs the comparison information.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to an eyeglass lens processing device for processing eyeglass lenses. [Background technology]

[0002] In the eyeglass lens processing device, various processes such as rough processing, finishing processing, and chamfering are performed on the eyeglass lens using processing tools, thereby processing the eyeglass lens into a desired shape.

[0003] However, as the number of eyeglass lenses processed by eyeglass lens processing devices increases, problems such as breakage and deterioration occur in processing tools. For this reason, techniques for inspecting whether or not there is a problem with the processing tools have been proposed. For example, Patent Document 1 discloses an inspection unit that inspects whether or not there is an unprocessed portion of the eyeglass lens by contacting a probe with the front or rear surface of the eyeglass lens, and if there is an unprocessed portion of the eyeglass lens, it is determined that there is a problem with the processing tool. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-198359 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional devices require an inspection process to check for defects in the processing tools in addition to the eyeglass lens processing process, which means that the inspection takes time and reduces the efficiency of eyeglass lens processing.

[0006] Furthermore, conventional devices determine that the processing tool is broken if there is an unprocessed portion on the eyeglass lens, and are unable to accurately determine whether the processing tool has deteriorated (deteriorated cutting ability).

[0007] In view of the above-described conventional technology, one of the technical objects of the present disclosure is to provide an eyeglass lens processing device that can efficiently determine defects in processing tools. In view of the above-described conventional technology, one of the technical objects of the present disclosure is to provide an eyeglass lens processing device that can effectively determine defects in processing tools. [Means for solving the problem]

[0008] The eyeglass lens processing device according to the present disclosure is an eyeglass lens processing device that processes an eyeglass lens with a processing tool by relatively changing the positional relationship between the eyeglass lens and the processing tool, a lens thickness acquisition means for acquiring the lens thickness of the eyeglass lens along a processing path set in accordance with the lens shape; Before processing the eyeglass lens with the processing tool, a predicted value of a processing load that is predicted to be applied to the processing tool when the eyeglass lens is processed with the processing tool is obtained. A first acquisition means acquires the predicted value at each processing point of the processing trajectory corresponding to the target lens shape based on a reference processing load for a reference lens thickness and a relationship between the reference lens thickness and the lens thickness at each processing point of the processing trajectory. First obtaining means, and the eyeglass lens by the processing tool Each machining point of the machining trajectory The actual load applied to the tool when actually processing At each processing point The apparatus is characterized by comprising a second acquisition means for acquiring an actual measurement value of the processing load, a comparison information acquisition means for acquiring comparison information that enables the predicted value and the actual measurement value to be compared, and an output means for outputting the comparison information. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to efficiently determine a malfunction of a processing tool while suppressing a decrease in processing efficiency. Also, it is possible to effectively determine a malfunction of a processing tool. [Brief explanation of the drawings]

[0010] [Figure 1] 2 is a diagram illustrating the configuration of a processing mechanism unit in the eyeglass lens processing device according to the embodiment. FIG. [Figure 2] FIG. 2 is a schematic configuration diagram of a lens shape measuring unit. [Figure 3] FIG. 2 is a control block diagram of the eyeglass lens processing device. [Figure 4] 10 is an example of a display screen when setting processing conditions. [Figure 5] FIG. 10 is a diagram showing an example of a machining path in rough machining. [Figure 6] 10 is an example of a predicted value of a machining load for a change over time in a machining trajectory. [Figure 7] 10 is a diagram showing the predicted value of the machining load superimposed with the actual measured value of the machining load that changes over time in the machining trajectory. FIG. [Figure 8] 10 is an example of a graph showing changes over time in the actual measured value and predicted value of the machining load when deterioration occurs in the roughing tool. [Figure 9] 10 is an example of a graph showing predicted values ​​and actual measured values ​​of a machining load in a machining trajectory of a finish machining process over time. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present embodiment will be described below with reference to the drawings, in which: Figures 1 to 9 are diagrams illustrating the eyeglass lens processing device according to the present embodiment and its operation.

[0012] [overview] An eyeglass lens processing device (for example, eyeglass lens processing device 1) processes eyeglass lenses with processing tools (for example, processing tool 163, roughing tool 423, chamfering tool 415) by relatively changing the positional relationship between the eyeglass lens and the processing tool. For example, this eyeglass lens processing device includes a lens holding shaft (for example, lens chuck shaft 102) that holds the eyeglass lens, and a moving means (for example, moving unit 300) that changes the relative positional relationship between the processing tool and the eyeglass lens held by the lens holding shaft.

[0013] For example, the eyeglass lens processing device includes data acquisition means (for example, a control unit 50, a data acquisition unit 10). For example, the data acquisition means includes first acquisition means (for example, the control unit 50). For example, the first acquisition means acquires, before processing the eyeglass lens with the processing tool, a predicted value of the processing load that is predicted to be applied to the processing tool when the eyeglass lens is processed with the processing tool.

[0014] The processing load may include not only the processing load directly applied to the processing tool, but also the load indirectly generated on the rotation shaft of the processing tool (for example, the second processing tool drive shaft 412, the first processing tool drive shaft 410, the processing tool rotation shaft 161), or the load generated on the motor that rotates the rotation shaft of the processing tool. For example, the processing load applied to the processing tool is obtained based on the load current of the motor that rotates the processing tool.

[0015] For example, the first acquisition means obtains a predicted value based on the thickness of the eyeglass lens on a processing path used when processing the periphery of the eyeglass lens with a processing tool. In this case, for example, the eyeglass lens processing device may be equipped with a lens thickness acquisition means (e.g., the control unit 50, the lens shape measurement unit 200) that acquires the thickness of the eyeglass lens on the processing path. For example, the lens thickness acquisition means may acquire the lens thickness of the eyeglass lens on the processing path based on the front surface shape and the back surface shape of the eyeglass lens corresponding to the lens shape.

[0016] For example, the first acquisition means may acquire a predicted value of the processing load based on the lens thickness on the processing trajectory and the reference processing load for the reference lens thickness. The reference processing load for the reference lens thickness may be stored in a storage means (e.g., memory 20) and retrieved from the storage means by the data acquisition means.

[0017] For example, the first acquisition means may acquire the predicted value of the processing load as a value of change over time in the processing trajectory used when processing the periphery of the eyeglass lens. For example, the first acquisition means may acquire the predicted value of the processing load based on the lens material of the eyeglass lens. Since the processing load varies depending on the lens material, the predicted value of the processing load according to the lens material can be obtained with greater accuracy. In this case, for example, the eyeglass lens processing device may be equipped with a material acquisition means (e.g., data acquisition unit 10) that acquires the lens material. For example, the standard processing load for a standard lens thickness may be stored in a storage means for each lens material and acquired based on setting information for the lens material. For example, typical lens materials include plastic, polycarbonate, and acrylic.

[0018] For example, the first obtaining means may obtain a predicted value of the processing load based on the processing amount of the eyeglass lens by the processing tool. In this case, for example, the eyeglass lens processing device may include means (for example, data obtaining unit 10) for obtaining the processing amount of the eyeglass lens processed by the processing tool with respect to the processing trajectory used when processing the periphery of the eyeglass lens.

[0019] For example, the data acquisition means includes second acquisition means (e.g., control unit 50). For example, the second acquisition means acquires an actual measurement value of the actual processing load imposed on the processing tool when the processing tool actually processes the eyeglass lens. For example, the second acquisition means obtains the actual measurement value of the processing load from the load current of a motor (e.g., motor 421, motor 160) that rotates the processing tool. For example, the second acquisition means may acquire the actual measurement value of the processing load as a value of change over time in the processing trajectory used when processing the periphery of the eyeglass lens with the processing tool.

[0020] For example, the eyeglass lens processing apparatus includes a comparison information acquisition means (e.g., a control unit 50). For example, the comparison information acquisition means acquires comparison information that enables a comparison between a predicted value of the processing load acquired by a first acquisition means and an actual value of the processing load acquired by a second acquisition means. For example, the eyeglass lens processing apparatus includes an output means (e.g., a control unit 50) that outputs the comparison information acquired by the comparison information acquisition means. For example, the output means may output the comparison information to a display means (e.g., a display 60), thereby displaying the comparison information on the display means. By checking the comparison information displayed on the display means, the operator can accurately determine whether or not there is a defect in the processing tool (which may also include the degree of the defect in the processing tool). Furthermore, the comparison information acquisition means does not require an operation such as contacting a contact point with the front or rear surface of the eyeglass lens to determine whether or not there is a defect in the processing tool, thereby enabling efficient determination of a defect in the processing tool without reducing processing efficiency.

[0021] Furthermore, for example, the comparison information acquisition means may determine whether or not there is a malfunction in the processing tool based on a comparison process between a predicted value and an actual value of the processing load. For example, the comparison information includes whether or not there is a malfunction in the processing tool. This allows for efficient and accurate determination of whether or not there is a malfunction in the processing tool. For example, the malfunction in the processing tool may be at least one of breakage of the processing tool and deterioration (decrease in cutting ability) of the processing tool due to damage or wear of the processing tool.

[0022] For example, the comparison information acquisition means may determine whether or not there is a malfunction in the processing tool based on a comparison process between a change in the predicted value of the processing load over time and a change in the actual value over time. This makes it possible to accurately determine whether or not there is a malfunction in the processing tool when the processing tool breaks during processing.

[0023] For example, the comparison information acquisition means may perform at least one of a first determination that the malfunction of the processing tool is breakage when the actual measurement value is lower than the predicted value by a predetermined first difference amount, and a second determination that the malfunction of the processing tool is deterioration when the actual measurement value is higher than the predicted value by a predetermined second difference amount. This allows the type of malfunction of the processing tool (e.g., breakage of the processing tool and deterioration of the processing tool) to be accurately determined.

[0024] For example, the first acquisition means may acquire an average value of predicted values ​​of the processing load during the period from the start to the end of processing of the eyeglass lens, and the second acquisition means may acquire an average value of actual measured values ​​of the processing load during the period from the start to the end of processing of the eyeglass lens. In this case, the comparison information acquisition means may determine whether or not there is a malfunction in the processing tool based on a comparison process between the average value of the predicted values ​​and the average value of the actual measured values. This allows for better determination of whether or not there is a malfunction in the processing tool.

[0025] Furthermore, for example, the comparison information acquisition means may determine a malfunction of the processing tool based on a comparison process between the trend of change (increase and decrease) in the predicted value of the processing load over time and the trend of change (increase and decrease) in the actual measured value of the processing load over time. For example, if the predicted value of the processing load shows a trend of increase and decrease over time but the actual measured value does not show the same trend (for example, if the actual measured value shows no substantial change until the end of processing), it is determined that the processing tool has a malfunction such as breakage.

[0026] For example, the present eyeglass lens processing device may be equipped with a processing load information acquisition means (e.g., data acquisition unit 10) that acquires processing load information resulting from individual differences in eyeglass lens processing devices as a factor in fluctuations in the processing load when processing eyeglass lenses with a processing tool, and the predicted and measured processing load values ​​may be set to the same processing load standard based on the processing load information. This makes it possible to eliminate the influence on the processing load resulting from individual differences in eyeglass lens processing devices, and to better determine defects in the processing tool.

[0027] [Example] One exemplary embodiment of the present disclosure will be described with reference to the drawings, in which: Fig. 1 is a diagram illustrating the configuration of a processing mechanism unit in an eyeglass lens processing apparatus 1 according to the embodiment.

[0028] For example, the eyeglass lens processing apparatus 1 includes a lens holding unit 100, which is an example of a lens holding means having a lens holding shaft for holding an eyeglass lens (hereinafter referred to as lens LE), which is a lens to be processed. For example, the eyeglass lens processing apparatus 1 includes a lens shape measuring unit 200 configured to acquire the shape of the lens LE (refractive surface shape of the lens LE, outer shape of the lens LE) (see FIG. 2). In this embodiment, the lens shape measuring unit 200 is provided on a base 2 of the eyeglass lens processing apparatus 1.

[0029] For example, the eyeglass lens processing apparatus 1 includes a first processing tool unit 150. The first processing tool unit 150 is configured to rotate a processing tool that processes the periphery of the lens LE. For example, the eyeglass lens processing apparatus 1 includes a second processing tool unit 400. The second processing tool unit 400 is configured to rotate a rough processing tool (e.g., rough processing tool 423) that roughly processes the periphery of the lens LE. For example, the eyeglass lens processing apparatus 1 includes a moving unit 300, which is an example of a changing means for changing (adjusting) the positional relationship between the lens LE held by the lens holding shaft and various components such as the processing tool. The moving unit 300 is used to change (adjust) the relative positional relationship between the lens LE and the processing tool held by the first processing tool unit 150. The moving unit 300 is also used to change (adjust) the relative positional relationship between the lens LE and the processing tool held by the second processing tool unit 400. The moving unit 300 is also used to change (adjust) the relative positional relationship between the lens LE and the measuring piece of the lens shape measuring unit 200.

[0030] <Lens holding unit> For example, the lens holding unit 100 includes a lens chuck shaft 102, which is an example of a lens holding shaft for holding (clamping) 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 by the left arm 101L of the carriage 101, and the lens chuck shaft 102R is rotatably held by the right arm 101R of the carriage 101. The lens chuck shaft 102 (i.e., the lens LE) is rotated by a motor 120, which is an example of lens rotation means. In addition, a motor 110 is disposed on the right arm 101R for moving the right chuck shaft 102R toward the left chuck shaft 102L. When the right chuck shaft 102R is moved toward the left chuck shaft 102L, the lens LE is held by the two lens chuck shafts 102L and 102R.

[0031] <First processing tool unit> The first processing tool unit 150 includes a motor 160 for rotating a processing tool rotation shaft 161. The processing tool rotation shaft 161 is rotatably held by a rotation shaft holding unit 162 in a positional relationship parallel to the lens chuck shaft 102. The rotation shaft holding unit 162 is attached to the base 2. A plurality of processing tools 163 for processing the periphery of the lens LE are attached to the processing tool rotation shaft 161. For example, the processing tools 163 include at least one of a finishing tool 163a for high-curve lenses, a mirror-finishing tool 163b, a finishing tool 163c for low-curve lenses, and a roughing tool 163d for glass. The mirror-finishing tool 163b and the finishing tool 163c each include at least one of a V-groove for beveling and a flat finishing surface for flat processing. For example, a grinding wheel is used as the processing tool 163, but a cutter may also be used.

[0032] <Second processing tool unit> For example, the second processing tool unit 400 is disposed behind the carriage 101. The second processing tool unit 400 includes a roughing tool 423 for roughly processing the peripheral edge of the lens LE. For example, a cutter is used as the roughing tool 423, but an end mill may also be used. Furthermore, for example, the second processing tool unit 400 includes a chamfering tool 415 for chamfering the corners of the edge of the lens LE. For example, a grinding wheel is used as the chamfering tool 415.

[0033] The chamfering tool 415 is connected to a first processing tool drive shaft 410. The first processing tool drive shaft 410 is rotatably held inside the second rotation shaft A2. The first processing tool drive shaft 410 is also connected to a drive shaft 400a of a motor 421 via a connecting member (not shown). When the motor 421 is rotated, the chamfering tool 413 is rotated.

[0034] The roughing tool 423 is attached to a second processing tool drive shaft 412. The second processing tool drive shaft 412 is rotatably held by a holder 411. The second processing tool drive shaft 412 is connected to a drive shaft 400a of a motor 421 via a connecting member (not shown). In this embodiment, the second processing tool drive shaft 412 is disposed at a position different from the drive shaft 400a of the motor 421. That is, the rotation of the drive shaft 400a of the motor 421 is transmitted to the second processing tool drive shaft 412 via a one-way clutch (not shown), a bearing (for example), etc. As a result, the rotation of the motor 421 is transmitted to the second processing tool drive shaft 412.

[0035] The second processing tool unit 400 includes a rotation mechanism for changing the position of the processing tool. For example, a first rotation axis A1 is disposed inside the base portion 402 and fixed to the support block 401. The base portion 402 is connected to the first rotation axis A1 via a bearing (not shown) and is held rotatably about the first rotation axis A1 relative to the support block 401. The first rotation axis A1 is rotated by driving a motor (not shown). The base portion 402 is rotated about the first rotation axis A1 by the rotation of the first rotation axis A1.

[0036] The second rotation axis A2 is rotatably connected inside the base portion 402. The second rotation axis A2 is a rotation axis different from the first rotation axis A1. The second rotation axis A2 is rotated by driving a power source (e.g., a motor) not shown. The rotation of the second rotation axis A2 causes the holding portion 411 connected to the second rotation axis A2 to rotate about the second rotation axis A2. As a result, the second processing tool drive shaft 412 held by the holding portion 411 is rotated about the second rotation axis A2, and the rough processing tool 423 is moved to a predetermined processing position.

[0037] The configuration of the second processing tool unit 400 can be that described in Japanese Patent Application Laid-Open No. 2017-177234, so please refer to this publication for details.

[0038] <Mobile Unit> The moving unit 300 includes a first moving unit 310 that relatively changes the positional relationship between the lens chuck shaft 102 and the processing tool rotation shafts (such as the processing tool rotation shaft 161 and the second processing tool drive shaft 412) in the inter-axial distance direction (hereinafter referred to as the Y direction). The moving unit 300 also includes a second moving unit 330 that relatively changes the positional relationship between the lens LE and the processing tools (such as the processing tool 163 and the rough processing tool 423) in the axis L1 direction of the lens chuck shaft 102 (hereinafter referred to as the X direction).

[0039] The first moving unit 310 is also used to change the positional relationship in the Y direction between the tracing stylus 260 and the tracing stylus 263 (see FIG. 2) held by the lens shape measuring unit 200 and the lens LE held by the lens chuck shaft 102. The second moving unit 330 is also used to change the positional relationship in the X direction between the tracing stylus 260 (see FIG. 2) held by the lens shape measuring unit 200 and the lens LE held by the lens chuck shaft 102. In this embodiment, the Y direction is a direction perpendicular to the X direction.

[0040] The first moving unit 310 includes a motor 315. The rotation of the motor 315 moves the moving support base 301 in the X direction. As a result, 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 first moving unit 310 may be configured to move each processing tool, such as the roughing tool 423, and each measuring element, such as the measuring element 290, in the X direction.

[0041] The second moving unit 330 includes a motor 335 for moving the carriage 101 (lens chuck shaft 102) in the Y direction. A shaft 333 extending in the Y direction is attached to the moving support base 301. A motor 335 is fixed to the moving support base 301. 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.

[0042] 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 each processing tool such as the rough processing tool 423 and the measuring probe such as the measuring probe 290 in the Y direction.

[0043] <Lens shape measurement unit> 2 is a schematic configuration diagram of the lens shape measuring unit 200. The lens shape measuring unit 200 includes a tracing stylus 260 for measuring the refractive surface shape of the lens LE. In this embodiment, the tracing stylus 260 includes a tracing stylus 261 that comes into contact with the front surface of the lens LE and a tracing stylus 262 that comes into contact with the rear surface of the lens LE. The tracing stylus 262 has a cylindrical side surface. The side surface of the tracing stylus 262 is used as a tracing stylus 263 that comes into contact with the outer periphery of the lens LE to measure the external shape of the lens LE. The lens shape measuring unit 200 also includes a sensor (detector) 271 that detects the movement positions of the tracing stylus 261 and 262 in the X direction, and a sensor (detector) 273 that detects the movement position of the tracing stylus 263 in a direction away from the lens chuck shaft 102.

[0044] The tracing styluses 261 and 262 are held by an arm 265 that is movable in the X direction. In this embodiment, the arm 265 has a U-shape. Also, in this embodiment, the arm 265 is attached to a support 267, and the support 267 is held by a block 269 so as to be movable in the X-axis direction. The support 267 is biased by springs (biasing members) (not shown) toward the front and rear of the lens LE, with the state in FIG. 2 being its neutral position. The movement positions of the tracing styluses 261 and 262 in the X direction are detected by a sensor 271 via the arm 265 and the support 267. A well-known configuration is used for the sensor 271.

[0045] When measuring the refractive surface shape of the lens LE, the lens LE is rotated by rotating the lens chuck shaft 102, and the movement of the lens chuck shaft 102 in the Y direction is controlled based on the target lens shape, whereby the positions of the front and rear surfaces of the lens LE in the X direction corresponding to the target lens shape are detected by the sensor 271. Note that in the device of the embodiment, the refractive shapes of the front and rear surfaces of the lens LE are measured by also utilizing the movement control of the lens chuck shaft 102 in the X direction.

[0046] Furthermore, the support column 267 is attached to the block 269 so as to be tiltable rearward (in a direction away from the lens chuck shafts 102L and 102R) around an axis S1 extending parallel to the X direction. The support column 267 is constantly biased forward by a spring (biasing member) not shown. The forward tilt of the support column 267 is limited in the state shown in FIG. 2 by a limiting member not shown. When measuring the outer shape of the lens LE, the tracing stylus 263 comes into contact with the outer periphery of the lens LE, and the lens LE is rotated, thereby moving the tracing stylus 263 in a direction away from the lens chuck shaft 102 in accordance with the outer shape of the lens LE. That is, the support column 267 is tilted around the axis S1 in accordance with the outer shape of the lens LE. The tilt of the support column 267 is detected by a sensor 273. That is, the sensor 273 detects the movement position of the tracing stylus 263 in a direction away from the lens chuck shaft 102. As a result, the outer shape of the lens LE centered on the lens chuck shaft 102 is measured.

[0047] <Control system configuration> 3 is a control block diagram of the eyeglass lens processing apparatus 1. The eyeglass lens processing apparatus 1 includes a control unit 50. The electrical components (motors, sensors, etc.) of each unit shown in FIGS. 1 and 2 are connected to the control unit 50. The control unit 50 controls the motors of each unit to process the periphery of the lens LE.

[0048] The eyeglass lens processing apparatus 1 includes a data acquisition unit 10. The data acquisition unit 10 may also function as an input unit. For example, the data acquisition unit 10 includes a display 60. For example, the data acquisition unit 10 includes an input unit 13. For example, the display 60, which is an example of a display means, may have a touch panel function and be configured to include the input unit 13. For example, the control unit 50 constitutes part of the data acquisition unit 10 and acquires various data. For example, the control unit 50 also functions as an output means for outputting various information. A memory 20 is connected to the control unit 50, and various data acquired by the data acquisition unit 10 is stored in the memory 20. The memory 20 also stores various programs for controlling the operation of the eyeglass lens processing apparatus 1. For example, the memory 20 stores a program for obtaining a predicted value (described later) of a processing load when processing the lens LE with a processing tool. For example, the memory 20 stores a program related to peripheral processing of the lens LE.

[0049] The data acquisition unit 10 may be connected to a lens shape measuring device 30. For example, the lens shape measuring device 30 obtains the lens shape of the lens LE (the target outer shape for processing the peripheral edge of the lens LE) by measuring the rim of an eyeglass frame. The lens shape stored in the memory 20 may be used. The data acquisition unit 10 obtains lens shape data from the lens shape measuring device 30 or the memory 20. Note that the "lens shape" is a two-dimensional shape defined by a radius vector length and a radius vector angle.

[0050] <Operation> The operation of the eyeglass lens processing apparatus 1 having the above configuration will be described. First, the data acquisition unit 10 acquires the lens shape data TD (radial length r, radial angle θ) of the lens LE. For example, the contour shape of the rim of the eyeglass frame measured by the lens shape measuring device 30 is input to the data acquisition unit 10. The lens shape data TD may be acquired by the data acquisition unit 10 by calling up data stored in the memory 20.

[0051] Once the lens shape data TD has been acquired, the operator sets (inputs) the processing conditions for processing the periphery of the lens LE using the display 60. FIG. 4 shows an example of the screen of the display 60 when setting the processing conditions. In FIG. 4, a right-eye lens shape TGR and a left-eye lens shape TGL are displayed on a screen 610 of the display 60. For processing the periphery of the lens LE, layout data for locating the optical center position of the lens LE relative to the lens shapes is input. For example, the layout data includes the distance FPD between the left and right lens centers (the distance between the geometric center TCR of the right-eye lens TGR and the geometric center TCL of the left-eye lens TGL), the interpupillary distance PD (the distance between the optical center OCR for the right eye and the optical center OCL for the left eye), and the height distance of the optical centers relative to the geometric centers of the left and right lens shapes. These values ​​can be input using a numeric keypad that appears when the display field on the screen is touched.

[0052] Furthermore, as a processing condition, the material of the lens LE can be set in the input field 621a. For example, plastic, polycarbonate, acrylic, etc. can be selected as the material of the lens LE. Information on the material of the lens LE set in the input field 621a is acquired by the data acquisition unit 10. Other processing conditions include the frame type (metal, cell, rimless, etc.), the lens periphery processing mode (auto beveling, forced beveling, flat processing, etc.), whether or not to perform mirror finishing, whether or not to perform chamfering, and the lens chucking mode (frame center mode, optical center mode) can be set in the input fields 621b, 621c, 621d, 621e, and 621f. Note that if chamfering is set to "yes" in the input field 621d, the chamfer width can also be set (for example, large, medium, or small can be selected, or the chamfer width can be set numerically).

[0053] After setting the processing conditions, the operator holds the lens LE on the lens chuck shaft 102 and starts the operation of the eyeglass lens processing apparatus 1. Prior to peripheral processing of the lens LE, the control unit 50 executes an eyeglass lens shape measurement program, and the lens shape measuring unit 200 measures the shape of the lens LE. For example, first, the outer shape of the lens LE is measured. The control unit 50 drives the first moving unit 310, and moves the lens LE to a position within the measurement range of the tracing stylus 263. Thereafter, the second moving unit 330 is driven, and the lens LE is moved in the Y direction (toward the tracing stylus 263) so that the outer periphery of the lens LE comes into contact with the tracing stylus 263. The sensor 273 detects that the lens LE has come into contact with the tracing stylus 263. Then, the lens LE is rotated once while in contact with the tracing stylus 263, and the outer shape of the lens LE is measured. In this embodiment, by utilizing the movement control of the lens chuck shaft 102 in the Y direction, the outer shape data of the lens LE is obtained based on the movement position of the lens chuck shaft 102 in the Y direction and the detection result of the sensor 273. The outer shape data of the lens LE is stored in the memory 20.

[0054] Next, the lens shape measuring unit 200 measures the front and rear surface shapes of the lens LE. The measurement of the front and rear surface shapes of the lens LE is performed, for example, based on two measurement trajectories (first measurement trajectory, second measurement trajectory) corresponding to target lens shape data. For example, the first measurement trajectory may be the trajectory of the target lens shape, or may be a trajectory obtained by varying a certain distance in the radial direction (inward or outward) relative to the target lens shape. For example, the second measurement trajectory is a trajectory that is a certain distance (for example, 0.8 mm) outward from the first measurement trajectory.

[0055] For example, the lens front surface is measured first. The control unit 50 controls the driving of the moving unit 300, and moves the lens LE (lens chuck shaft 102) in the Y direction so that the position of the tracing stylus 261 in the Y direction is the position of the first measurement locus. Next, the lens LE is moved in the X direction so that the lens front surface comes into contact with the tracing stylus 261. The contact of the lens front surface with the tracing stylus 261 is detected based on the output signal of the sensor 271. The position of the lens front surface in the X direction at this time is obtained based on the control data (driving data of the motor 315) for moving the lens chuck shaft 102 in the X direction and the detection data of the sensor 271. Thereafter, the lens LE is rotated and the driving of the moving unit 300 is controlled, and the lens LE is moved in the Y direction so that the position of the tracing stylus 261 in the Y direction is the position of the measurement locus. Furthermore, the lens LE is moved in the X direction based on the measurement result of the lens front surface shape so that the position of the tracing stylus 261 in the X direction is within a predetermined range. Then, by rotating the lens LE once, the shape of the lens front surface in the X direction on the first measurement trajectory is acquired based on the detection result of the sensor 271 and the control data in the X direction of the lens chuck shaft 102. Note that the control operation during this measurement can employ the technology described in Japanese Patent Laid-Open No. 2014-4678, so please refer to that publication for details.

[0056] Next, the front surface of the lens is measured based on the second measurement trajectory under similar control. The shape of the front surface of the lens is obtained based on the two measurement trajectories, and thus the curve information of the front surface of the lens and the tilt angle near the target shape are obtained.

[0057] Next, the lens rear surface is similarly measured based on the first and second measurement trajectories. The shape of the lens rear surface is obtained based on the two measurement trajectories, thereby obtaining curve information of the lens rear surface and the tilt angle near the target lens shape. The refractive surface shape data of the lens front and rear surfaces is stored in memory 20.

[0058] <Acquisition of predicted machining load values> Once the shape data of the lens LE is obtained, prior to rough processing of the lens LE, the control unit 50 acquires a predicted value of the processing load that is expected to be imposed on the rough processing tool 423 when the rough processing tool 423 rough processes the lens LE. For example, the predicted value of the processing load of the rough processing tool 423 is acquired based on the target lens shape data, the lens material acquired by the settings on the screen 610, the lens shape data acquired by measurement by the lens shape measuring unit 200, etc. A method of acquiring the predicted value of the processing load will be described below.

[0059] Here, the memory 20 stores, for each material of the lens LE, a reference processing load PLS for a reference lens thickness Ts (for example, 2 mm) when the lens LE is rough-processed by the rough-processing tool 423. For example, the reference processing load PLS is obtained as follows.

[0060] For example, the lens LE is made of a common CR39 plastic and has a constant reference lens thickness Ts (e.g., 2 mm) (hereinafter, referred to as the reference lens LES). The reference lens LES is held by the lens chuck shaft 102 and is roughly machined by the roughing tool 423. For example, the machining path during roughing is set to a circular lens shape (e.g., 40 mm in diameter). During roughing, the control unit 50 controls the rotation of the lens LE and the drive of the moving unit 300 based on the machining path. During this roughing, the control unit 50 controls the movement speed of the contact point between the reference lens LES and the roughing tool 423 on the machining path so that it is constant. The machining load during this roughing is obtained, for example, from the load current of the motor 421 that rotates the roughing tool 423. For example, the machining load is obtained from the start to the end of machining, and the average value of the machining load during this period is stored in the memory 20 as the reference machining load PLS. The processing load is related to the rotation speed of the motor 421 that rotates the roughing tool 423 (for example, the higher the rotation speed, the higher the processing load). For this reason, the reference rotation speed of the motor 421 may also be stored in the memory 20. If the rotation speed of the motor 421 during actual processing differs from the reference rotation speed, the processing load may be corrected based on the relationship of the actual rotation speed to the reference rotation speed.

[0061] Other lens materials are also processed under similar conditions, and the standard processing load PLS for that lens material is obtained and stored in memory 20. Note that instead of storing the standard processing load PLS for each lens material, it is also possible to obtain a coefficient when the lens material is polycarbonate and a coefficient when the lens material is acrylic for the standard processing load PLS when the lens material is plastic, and store these in memory 20.

[0062] Next, acquisition of a predicted value of the processing load during rough processing of the lens LE will be described with reference to Figures 5 and 6. It is assumed that plastic is selected as the lens material (the lens material is acquired by the control unit 50).

[0063] FIG. 5 is a diagram showing an example of a machining path in rough machining. Note that FIG. 5 illustrates the movement of the rough machining tool 423 relative to the lens LE. In FIG. 5, the rough machining tool 423 is assumed to move along paths M1, M2, M3, and M4 in this order. The rough machining path LM3 is determined so as to leave a predetermined finishing allowance (e.g., 0.8 mm) relative to the target lens shape data TD (i.e., the finish machining path LF1). The machining path LM1 of the path M1 is a path that runs from the periphery of the lens LE to the rough machining path LM3. The machining path LM2 of the path M2 is a path that runs 180 degrees opposite to the machining path LM1 and runs from the periphery of the lens LE to the rough machining path LM3. For example, in rough machining, after the rough machining tool 423 moves along the machining path LM1 of the path M1, the rough machining tool 423 temporarily moves back along the path M1 and away from the lens LE. Next, after the lens LE is rotated 180 degrees, the roughing tool 423 is moved along the machining path LM2 of the path M2. After that, the lens LE is rotated once, and the roughing tool 423 is moved along the roughing path LM3 to proceed along paths M3 and M4. As a result, the lens portions outside the paths M1, M2, M3, and M4 are cut off.

[0064] The control unit 50 obtains predicted values ​​of the processing loads for the processing paths LM1, LM2, and LM3 based on the lens thickness for each processing path. The lens thickness for each processing path is obtained based on the measurement results of the lens shape measurement unit 200. That is, the lens thickness for the processing path LM3 is obtained by subtracting the measurement results of the front and rear surfaces of the lens for the measurement path (first or second measurement path) corresponding to the lens shape. The lens thickness for the processing paths LM1 and LM2 is obtained based on the lens thickness for the processing path LM3, the curve information for the front and rear surfaces of the lens, and the distance from the processing path LM3 to the periphery of the lens. The curve information for the front and rear surfaces of the lens are obtained based on the measurement results of the two measurement paths (first and second measurement paths). The distance from the processing path LM3 to the periphery of the lens is obtained based on the measurement results of the outer shape of the lens LE.

[0065] The control unit 50 calculates a predicted value PLf of the machining load for the machining path based on the lens thickness at each machining path. That is, the control unit 50 calculates the relationship between the lens thickness at each machining point on the machining path and the reference lens thickness Ts stored in the memory 20. In this case, the machining path may be the path of the center of the roughing tool 423 based on the diameter of the roughing tool 423. The control unit 50 calculates the predicted value PLf of the machining load for the machining path by multiplying the calculated relationship of the lens thickness ratio by the reference machining load PLS. For example, the machining points on the machining path are located every 0.1 mm on the machining paths LM1 and LM2, and 1,000 points are located every 0.36 degrees of radius vector angle on the machining path LM3. The predicted value PLf of the machining load may also be calculated by calculating the machining volume (volume) between each machining point and then calculating the relationship between the calculated machining volume and the reference machining load PLS for the machining volume at the reference lens thickness Ts. The control unit 50 obtains the predicted value PLf on the processing path as a value of change over time, assuming that the movement speed of the contact point between the processing point on the processing path of the lens LE and the roughing tool 423 is the same as that controlled during actual roughing. For example, the movement speed of the contact point between the processing point and the roughing tool 423 is controlled to be constant.

[0066] Fig. 6 shows an example of a predicted value PLf of the machining load for changes over time in the machining trajectory. In Fig. 6, the horizontal axis indicates elapsed time (sec), and the vertical axis indicates the magnitude of the machining load. For example, in this embodiment, the machining load of the roughing tool 423 is obtained from the load current of the motor 421 that rotates the roughing tool 423, so the machining load is expressed in units of a percentage (%) of the rated output (W) of the motor 421.

[0067] Note that Figure 6 shows an example of a lens with a minus refractive power, where the lens thickness is thicker at the periphery than at the center. The predicted value PLf fluctuates according to changes in the lens thickness (machining amount per unit time) along the machining paths LM1, LM2, and LM3. The predicted value PLf at the boundary between paths M3 and M4 drops to near zero machining load because the lens LE is machined until it reaches the machining path M3 during rough machining along path M1 (machining path LM1). The machining load after the completion of machining along the machining paths LM1 and LM2 also actually drops to near zero, but this reduction in machining load is omitted in the illustration to show the machining load of the machining operation of the rough machining tool 423 for each machining path (the same applies to Figures 7 and 8 described below).

[0068] <Rough processing> After acquiring the predicted value of the machining load, the control unit 50 rotates the holder 411 of the second machining tool drive shaft 412 around the second rotation axis A2 to position the roughing tool 423 at the machining position. Next, the control unit 50 controls the drive of the first moving unit 310 to position the lens LE held by the lens chuck shaft 102 in the X direction for roughing. Then, the control unit 50 roughly machines the lens LE by rotating the lens chuck shaft 102 and driving the second moving unit 330 to change the position in the Y direction based on the machining trajectories LM1, LM2, and LM3. As shown in FIG. 5 , the roughing tool 423 moves along the machining trajectory LM1 of the path M1, the machining trajectory LM2 of the path M2, and the machining trajectory LM3 of the paths M3 and M4. During this roughing, the control unit 50 controls each drive unit so that the moving speed of the contact point between the lens LE and the roughing tool 423 along the machining trajectory is constant.

[0069] <Determining the failure when the roughing tool breaks> The operation of determining whether a malfunction of the roughing tool 423 occurs during roughing will be described. During roughing, the control unit 50, in parallel with controlling the drive of each drive unit, acquires the actual measured value PLm of the machining load imposed on the roughing tool 423 when the roughing tool 423 actually rough-machines the lens LE. For example, the control unit 50 obtains the actual measured value PLm of the machining load from the load current of the motor 421 that rotates the roughing tool 423. At this time, similar to the predicted value PLf, the control unit 50 acquires the actual measured value PLm as a value of change over time in the machining trajectory. Note that the actual measured value PLm of the machining load used for determination may be a value obtained by acquiring an average value at regular time intervals (time intervals longer than the minute time) shifted by a minute time and plotting this value over time. This eliminates the influence of temporary, minute fluctuations in the load current of the motor 421, enabling proper determination of a malfunction of the machining tool.

[0070] The control unit 50 determines whether a malfunction has occurred in the roughing tool 423 based on a comparison between the predicted machining load PLf and the actual measured machining load PLm. Figure 7 shows the predicted machining load PLf of Figure 6 superimposed with the actual measured machining load PLm, which shows changes over time along the machining trajectory. For example, the control unit 50 determines that a malfunction such as breakage has occurred in the roughing tool 423 when the actual measured machining load PLm drops below the predicted value PLf by more than a predetermined difference ΔJPa based on a comparison between the predicted value PLf and the actual measured machining load PLm. Note that when a thin portion of the lens is being machined, or when the load current of the motor 421 of the machining tool 423 temporarily changes, the actual measured machining load PLm may temporarily drop below the difference ΔJPa. Therefore, the control unit 50 may determine whether a malfunction has occurred in the roughing tool 423 based on whether the drop in the actual measured machining load PLm by more than the difference ΔJPa continues over time. 7, the actual measurement value PLm drops below the predicted value PLf by more than the difference ΔJPa at time ta1, and this state continues until time ta2 when machining ends. Therefore, the drop in the actual measurement value PLm below the predicted value PLf is not temporary and continues until machining ends, so it can be determined that the roughing tool 423 has broken.

[0071] In the case of a lens LE with a positive refractive power, the lens thickness is thin near the end of processing, resulting in a small amount of processing. Therefore, if the roughing tool 423 breaks near the end of processing (in reality, the amount of processing is small, making the possibility of the roughing tool 423 breaking low), the difference between the predicted value PLf and the actual measured value PLm will be small, and a determination based on the difference ΔJPa may result in an erroneous determination. Even in this case, the possibility of an erroneous determination can be reduced by comparing the predicted value PLf with the actual measured value PLm. For example, in the area where the amount of processing is small, attention is paid to whether the predicted value PLf tends to increase or decrease over time until the end of processing. If the actual measured value PLm also shows the same trend as the predicted value PLf on average by the end of processing, it can be determined that the roughing tool 423 has not broken. On the other hand, if the predicted value PLf is on a downward trend but the actual measured value PLm does not show the same trend (there is essentially no change in the actual measured value PLm until the end of processing), it can be determined that the roughing tool 423 has broken.

[0072] In the case of a lens LE with a positive refractive power as described above, the inspection process of the inspection unit described in JP 2014-198359 A may be added only when the amount of machining is small and the predicted value PLf is determined to be below a predetermined threshold. That is, after rough machining is completed, the control unit 50 drives the lens shape measuring unit 200 and controls the stylus 260 to contact a refractive surface on at least one of the front and rear surfaces of the lens LE, the refractive surface being in the outer region of the rough machining path LM3. Then, based on the output signal of the sensor 271, when the stylus 260 is detected to have contacted the refractive surface of the lens LE, it is determined that there is an unmachined portion on the lens LE and that the rough machining tool 423 has been broken. This allows the presence or absence of a malfunction of the rough machining tool 423 to be confirmed.

[0073] When the control unit 50 determines that the roughing tool 423 has broken, it stops the processing operation of the eyeglass lens processing apparatus 1 and prevents the eyeglass lens processing apparatus 1 from proceeding to the next process of finish processing. The control unit 50 also displays the determination result of the breakage of the roughing tool 423 on the display 60 to notify the operator. The operator replaces the broken roughing tool 423 with a new roughing tool 423 and starts the roughing operation of the eyeglass lens processing apparatus 1 again. This allows for good processing to be performed without causing any inconvenience to the next process of finish processing.

[0074] In this way, without setting up a special inspection process after rough machining, defects in the processing tool are determined based on a comparison between predicted values ​​and actual measured values ​​obtained during rough machining, so that defects in the processing tool can be accurately determined while suppressing a decrease in processing efficiency.

[0075] <Determining defects when rough cutting tools are deteriorated> FIG. 8 is an example graph showing the time-dependent changes in the actual measured value PLm and the predicted value PLf when the roughing tool 423 is deteriorated (worn or chipped, etc.). When the roughing tool 423 is deteriorated, the actual measured value PLm of the machining load tends to be higher than the predicted value PLf. Therefore, when the actual measured value PLm becomes higher than the predicted value PLf by a predetermined difference ΔJPb or more, it is determined that the degree of deterioration of the roughing tool 423 has increased. The result of this determination is notified to the operator by being displayed on the display 60. Note that the determination of deterioration does not necessarily have to be based on time. For example, the average predicted value PLf of the machining load from the start to the end of machining may be compared with the average actual measured value PLm. Alternatively, the level of deterioration may be determined based on the difference between the average predicted value PLf and the average actual measured value PLm. The result of the determination of deterioration of the roughing tool 423 is displayed on the display 60 and notified to the operator. If the roughing tool 423 is judged to have a deterioration defect, the roughing is complete, and after the processing steps including the finishing are completed and the operation of the eyeglass lens processing device 1 is finished, the operator can replace the roughing tool 423 with a new roughing tool 423 and prepare for processing the next lens LE.

[0076] <Finishing and Determining Defects in Finishing Tools> Once the roughing is complete, the process moves to the finishing process. For example, if the lens LE is a low-curve lens and beveling is set, the control unit 50 uses a predetermined calculation method to determine a finishing path LF1 (see FIG. 5) including the X-direction position of the bevel apex position corresponding to the lens shape, based on the measurement results of the lens shape measuring unit 200. Thereafter, the control unit 50 controls the driving of the moving unit 300 based on the finishing path LF1, and causes the finishing tool 163c to finish the periphery of the roughly finished lens LE. During this finishing process, a malfunction of the finishing tool 163c may also be determined based on a comparison process between a predicted value and an actual measurement value of the processing load during the finishing process.

[0077] The acquisition of predicted and measured machining loads during finish machining will now be described. In finish machining, the periphery of the lens LE after rough machining is machined by a predetermined finishing allowance up to the finish machining trajectory LF1 (see FIG. 5), but the lens thickness varies depending on the radius vector angle. Therefore, the machining load on the finish machining trajectory LF1 also varies depending on the radius vector angle. For this reason, similar to the acquisition of predicted values ​​for the rough machining tool 423, the memory 20 stores a reference machining load PLFS for a reference lens thickness Ts (e.g., 2 mm) for each material of the lens LE when the lens LE is finish-machined using the finishing tool 163c. The reference machining load PLFS can be acquired in the same manner as for the rough machining tool 423. The machining load during finish machining can be obtained, for example, from the load current of the motor 160 that rotates the finishing tool 163c.

[0078] FIG. 9 is an example of a graph showing the predicted value PLFf and the actual measured value PLFm of the machining load on the finishing machining path over time. The predicted value PLFf is obtained based on the lens thickness on the finishing machining path LF1. The lens thickness on the finishing machining path LF1 is obtained based on the measurement results of the lens shape measurement unit 200. That is, the lens thickness at each machining point (e.g., 1,000 points) for each radius vector angle on the finishing machining path LF1 is obtained by the difference between the measurement results of the front surface of the lens and the measurement results of the rear surface of the lens on the measurement path (first measurement path) corresponding to the lens shape. The control unit 50 then determines the relationship between the ratio of the lens thickness at each machining point on the machining path to the reference lens thickness Ts stored in the memory 20. The control unit 50 determines the predicted value PLFf of the machining load by multiplying the determined lens thickness ratio relationship by the reference machining load PLFS for finishing. The predicted value PLFf may be obtained by calculating the machining amount (volume) between each machining point and based on the relationship between the calculated machining amount and the reference machining load PLFS for the machining amount at the reference lens thickness Ts. As in the case of rough machining, the control unit 50 calculates the predicted value PLFf on the machining path as a value of change over time, assuming that the movement speed of the contact point between the machining point on the machining path and the finishing tool 163c is the same as that in the control during actual finish machining.

[0079] The actual measured value PLFm of the machining load during actual finish machining is obtained from the load current of the motor 160 that rotates the finishing tool 163c. In Fig. 9, the actual measured value PLFm of the machining load that changes over time on the machining trajectory is shown superimposed on the predicted value PLFf of the machining load during finish machining.

[0080] The determination of a malfunction of the finishing tool 163c is made based on a comparison between the predicted value PLFf and the actual value PLFm of the machining load, similar to the determination of the roughing tool 423. For example, if the actual value PLFm is generally higher than the predicted value PLFf by more than a predetermined difference ΔJPFa, the control unit 50 determines that the finishing tool 163c has a malfunction due to deterioration and displays the determination result on the display 60. Note that, similar to the case of the roughing tool 423, the determination of a malfunction due to deterioration may be made by comparing the average predicted value PLFf of the machining load from the start to the end of the finish processing with the average actual value PLFm. Alternatively, the level of deterioration may be determined based on the difference between the average predicted value PLFf and the average actual value PLFm. For example, if the finishing tool 163c is a grindstone and it is determined that the finishing grindstone has a malfunction due to deterioration, the operator performs a dressing process to remove clogging from the grindstone after the processing operation of the eyeglass lens processing apparatus 1 is completed. This recovers the reduced cutting ability of the finishing tool 163c.

[0081] If the finishing tool 163c is a cutter (the finish cutter is attached to a rotating shaft provided separately from the grindstone tool) and it is determined that the finishing tool 163c has broken, the processing operation of the eyeglass lens processing device 1 is stopped, just as in the case of a broken roughing tool. Then, the operator replaces the roughing tool with a new one and resumes the finishing tool.

[0082] <Chamfering and determining defects in chamfering tools> If chamfering is set in the setting of processing conditions, after finishing, the corners of the periphery of the finished lens LE are chamfered by the chamfering tool 415. For example, in the case of chamfering the corners on the front surface of the lens, the control unit 50 controls the drive of the moving unit 300 based on the measurement results of the lens front surface by the lens shape measuring unit 200, the setting of the chamfer width, the chamfering trajectory determined based on the target lens shape, etc., so that the corners on the front surface of the lens LE are chamfered by the lens front surface processing unit of the chamfering tool 415. In the case of chamfering the corners on the rear surface of the lens, the control unit 50 similarly controls the drive of the moving unit 300 based on the measurement results of the lens rear surface by the lens shape measuring unit 200, the setting of the chamfer width, the chamfering trajectory determined based on the target lens shape, etc., so that the corners on the rear surface of the lens LE are chamfered by the lens rear surface processing unit of the chamfering tool 415.

[0083] During this chamfering process, a malfunction (deterioration) of the chamfering tool 415 may be determined based on a comparison between the predicted and measured values ​​of the processing load. For example, the memory 20 stores a reference processing load PLCS for each material of the lens LE when the chamfering tool 415 (the lens front surface processing unit and the lens rear surface processing unit) chamfers a reference chamfer width (e.g., 0.2 mm). The predicted processing load PLCf (not shown) during processing by the chamfering tool 415 is calculated by calling from the memory 20 the reference processing load PLCS based on the lens material set in the processing conditions and calculating the chamfer amount for each radius vector angle. The chamfer amount for each radius vector angle is calculated based on the chamfer width set in the processing conditions and the trajectory of the corner of the lens LE after finishing. To achieve a constant chamfer width, the moving speed of the contact point of the chamfering tool 415 relative to the processing point on the lens LE is kept constant.

[0084] The actual measured value PLCm (not shown) of the processing load during actual chamfering is obtained by detecting the load current of the motor 421 that rotates the chamfering tool 415. Then, for example, the presence or absence (degree) of a malfunction of the chamfering tool 415 is determined based on a comparison between the average of the actual measured values ​​PLCm and the average of the predicted values ​​PLCf from the start to the end of processing of the corners of the lens LE (the corners of the front and rear surfaces of the lens) by the chamfering tool 415. The determination result is displayed on the display 60 and notified to the operator.

[0085] <Example of transformation> In the above embodiment, the eyeglass lens processing apparatus 1 (control unit 50) determines whether a processing tool is defective. However, information enabling a comparison between predicted and actual processing load values ​​may be output, allowing the operator to determine whether a processing tool is defective. For example, as information enabling a comparison between predicted and actual processing load values, time-series graphs of predicted values ​​PLf and actual values ​​PLm shown in FIGS. 7 and 8 may be displayed on the display 60 in a superimposed or parallel fashion. The operator can determine whether the roughing tool 423 is broken or deteriorated by comparing the graph of predicted values ​​PLf and the graph of actual values ​​PLm. Furthermore, for example, when determining whether a finishing tool 163c is defective, time-series graphs of predicted values ​​PLFf and actual values ​​PFLm shown in FIG. 9 may be displayed on the display 60 in a superimposed or parallel fashion. Furthermore, the information that allows a comparison between predicted and actual values ​​of the processing load is not limited to the time-series graph displays shown in Figures 7 to 9, but may also be, for example, a display of the average values ​​of predicted and actual values ​​as numerical values. In this way, there are various forms of information that allow a comparison between predicted and actual values.

[0086] Furthermore, although the above-described determination of a malfunction of the processing tools has been described using the roughing tool 423, the finishing tool 163c, and the chamfering tool 415 as examples, the present invention is not limited to this. For example, when a groove digging tool (a tool for forming a groove on the periphery of the lens LE after flat finishing) is used as the processing tool, a malfunction of this groove digging tool may also be determined based on a predicted value of the processing load acquired before processing and an actual measured value of the processing load acquired during actual processing. Furthermore, a malfunction of other processing tools (the finishing tool 163a, the mirror-finishing tool 163b) attached to the processing tool rotation shaft 161 may also be determined using a method similar to that for the finishing tool 163c.

[0087] In the above embodiment, the movement speed of the processing tool (for example, the roughing tool 423) is constant when obtaining the predicted value and the actual measured value of the processing load, but this is not necessarily limited to this. As long as the predicted value and the actual measured value of the processing load can be compared based on the same standard, the movement speed of the processing tool may be different depending on the processing point of the processing trajectory (such as the target shape).

[0088] Furthermore, since there is a correlation between the processing load and the movement speed of the processing tool, the control unit 50 may control the movement speed of the processing tool based on the processing load, and use the predicted value and actual value of the movement speed of the processing tool as comparison information. For example, the control unit 50 controls the movement speed of the processing tool so that the processing load is constant. Even in this case, since the processing load and the movement speed are merely differences in physical quantities to be compared, it is possible to efficiently and accurately determine malfunctions of the processing tool, as in the above embodiment.

[0089] Furthermore, in obtaining predicted and measured values ​​of the processing load when processing the lens LE with each processing tool, in addition to differences in the material and processing amount of the lens LE, as other factors that cause fluctuations in the processing load, processing load information due to individual differences between eyeglass lens processing devices may be acquired, and standards (zero reference for the processing load) for the predicted and measured values ​​of the processing load may be aligned based on the acquired processing load information. For example, factors of individual differences that cause fluctuations in the processing load mainly include the rotational resistance of the rotation shaft of the processing tool and the rotational resistance due to the attachment of the processing tool to the rotation shaft.

[0090] For example, in the case of the roughing tool 423, the resistances include the rotational resistance of the holder 411, which rotatably holds the second processing tool drive shaft 412 of the roughing tool 423, and the rotational resistance of a transmission mechanism (such as a one-way clutch, not shown) for transmitting the rotation of the motor 421 to the second processing tool drive shaft 412. For example, a roughing tool 423 in a state without any malfunctions (new condition) is attached to the second processing tool drive shaft 412, and the motor 421 is rotated under the same conditions as during roughing when the roughing tool 423 is not processing the lens LE. The load current at this time is used as processing load information resulting from individual differences in the eyeglass lens processing apparatus. The obtained load current is offset to align with the zero reference of the processing load. By performing such a calibration operation, the influence of individual differences in the processing load of the eyeglass lens processing apparatus can be eliminated, and predicted and actual values ​​of the processing load when the reference is aligned can be obtained. This allows for better determination of processing tool malfunctions.

[0091] Although typical embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments shown here, and various modifications are possible within the scope of the same technical concept of the present disclosure. [Explanation of symbols]

[0092] 1 Eyeglass lens processing equipment 10 Data Acquisition Unit 50 control section 60 displays 102 Lens chuck axis 163 Processing tools 200 Lens Shape Measurement Unit 300 Mobile Units 415 Chamfering tool 423 Roughing tools

Claims

1. An eyeglass lens processing device that processes an eyeglass lens with a processing tool by relatively changing a positional relationship between the eyeglass lens and the processing tool, a lens thickness acquisition means for acquiring the lens thickness of the eyeglass lens along a processing path set in accordance with the lens shape; a first acquisition means for acquiring a predicted value of a processing load that is predicted to be applied to the processing tool when the processing tool processes the eyeglass lens before the eyeglass lens is processed by the processing tool, the first acquisition means acquiring the predicted value at each processing point of the processing trajectory corresponding to the lens shape based on a reference processing load for a reference lens thickness and a relationship between the lens thickness at each processing point of the processing trajectory and the reference lens thickness; a second acquisition means for acquiring an actual measurement value of a processing load applied to the processing tool at each processing point of the processing locus of the eyeglass lens when the processing tool actually processes the processing point; a comparison information acquisition means for acquiring comparison information that enables the predicted value and the actual measurement value to be compared; and an output means for outputting the comparison information.

2. 2. The eyeglass lens processing apparatus according to claim 1, The comparison information acquisition means determines whether or not there is a malfunction in the processing tool based on a comparison process between the trend of increase and decrease in the predicted value over time at each processing point and the trend of increase and decrease in the actual measured value at each processing point, and the comparison information includes determination information on whether or not there is a malfunction in the processing tool.

3. 2. The eyeglass lens processing apparatus according to claim 1, The comparison information acquisition means is characterized in that it makes at least one of the following judgments: a first judgment in which it is judged that the defect in the processing tool is breakage when the actual measurement value is lower than a predetermined first difference amount from the predicted value; and a second judgment in which it is judged that the defect in the processing tool is deterioration when the actual measurement value is higher than a predetermined second difference amount from the predicted value.

4. In the eyeglass lens processing apparatus according to claims 1 to 3, a material acquisition means for acquiring the material of the eyeglass lens; The eyeglass lens processing device, wherein the first obtaining means obtains the predicted value based on the obtained lens material.

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