JP4368693B2 - Lens grinding method and apparatus - Google Patents

Description

  The present invention relates to a lens grinding method and a lens grinding apparatus for processing a spectacle lens, in particular, a spectacle lens framed in a sports spectacle frame or the like.

  Until now, there has been no lens grinding apparatus that automatically realizes beveling of the peripheral edge of a spectacle lens such as a sports spectacle frame having a very large degree of curvature such as a +8 curve.

  In order to realize the grinding process of the spectacle lens to be framed in the spectacle frame having a large frame curve, an apparatus for inclining the bevel grindstone is already known (see Patent Documents 1 to 5).

  Further, in order to avoid interference between the inner curve of the spectacle lens and the direction of the groove of the grindstone, a lens grinding apparatus that performs beveling of the spectacle lens with a normal bevel grindstone being tapered is already known (Patent Documents 6 to 6). 10).

Furthermore, an apparatus that uses a small-diameter cutter and realizes roughing and finishing at the same time is also known (see Patent Publication 11).
Japanese Patent No. 2875378 JP 52-122992 A JP-A-48-66296 JP-A 49-30053 Japanese Utility Model Publication No. 53-71297 Japanese Utility Model Publication No. 53-99095 Japanese Utility Model Publication No. 55-103141 JP 2001-221740 A JP 2002-187053 A US Pat. No. 4,807,398 Japanese Patent Laid-Open No. 9-309051

  However, in a lens grinding apparatus in which the grindstone axis of the bevel grindstone is inclined with respect to the lens rotation axis that holds the spectacle lens, for example, a bevel around the edge of the spectacle lens such as a sports spectacle frame having a very large degree of curvature such as a +8 curve. It is impossible to realize machining, and even a lens grinding apparatus provided with a tapered beveling grindstone cannot similarly realize beveling. Furthermore, in order to grind all the processes with a single cutter, there is a possibility that a problem in durability will occur.

  Therefore, even if the bevel processing is performed on the periphery of the spectacle lens such as a sports spectacle frame having a very large degree of curvature such as a +8 curve, the bevel grinding can be efficiently performed and the spectacle lens after processing into the target lens shape. It is desirable that a normal bevel grindstone (for example, about 110 to 120 mm) and a small-diameter bevel grindstone (for example, about 24 mm) can be used properly according to the curve value of the bevel curve of the spectacle frame in which the frame is to be framed.

  Accordingly, the present invention provides a lens grinding method and a lens capable of efficiently performing beveling on the periphery of a spectacle lens formed in a lens shape according to the curve value of the bevel curve of the spectacle frame having a very large degree of curvature. An object is to provide a grinding apparatus.

In order to achieve this object, a lens grinding method according to the first aspect of the present invention includes a carriage that moves up and down around a rear carriage pivot, a pair of lens rotation shafts held at the front end of the carriage , and V A grinding wheel for grinding a peripheral edge of an unfinished spectacle lens that has a groove bevel grindstone and is held between the pair of lens rotation shafts, and a small-diameter bevel grindstone that is advanced and retracted relative to the spectacle lens. When the peripheral edge of the spectacle lens is processed using a lens grinding apparatus provided, an inter-axis distance adjusting means for adjusting an inter-axis distance between the lens rotation shaft and the grinding wheel is processed by the arithmetic control circuit. Actuation control is performed based on the data, and the peripheral edge of the raw spectacle lens is ground while adjusting the distance between the axes by rotating the front end of the carriage about the pivot axis. When the curve value of the bevel curve of the bevel formed on the peripheral edge of the spectacle lens processed into the target lens shape after grinding into a target lens shape with a grindstone is smaller than 4, the target lens shape with the V-groove bevel grindstone When the bevel curve value is 4 or more, the bevel curve value is 4 or more, and the V-groove bevel grindstone is switched to the small-diameter bevel grindstone. The small-diameter bevel grindstone is used to In the lens grinding method for performing beveling on the peripheral edge , Ln is ρn + R in the calculation of the moving radius ρn at the rotation angle nΔθ of the target lens shape data (ρn, nΔθ), and the interaxial distance Ln The virtual processing point of the spectacle lens is defined as Fi, and the actual contact position between the grinding wheel at the rotation angle nΔθ and the processing lens as the raw spectacle lens is represented by ρj. , Ln ′ is the actual distance between the lens rotation axis and the grinding wheel at the actual contact position ρj, and the difference between the calculated distance Ln and the actual distance Ln ′ is an error. When the difference angle between the virtual machining point Fi at the radius ρn of the rotation angle nΔθ and the contact machining point that is the actual contact position of the spectacle lens with the grinding wheel is dθn, ΔL Is obtained from the lens shape data (ρn, nΔθ) [n = 0, 1, 2, 3... J] and the radius R of the grinding wheel. The processing information (Ln, ρn, nΔθ) is determined from Ln and the target lens shape data (ρn, nΔθ), and the target lens shape data (ρn, nΔθ) is determined when the processing information (Ln, ρn, nΔθ) is determined. And the deviation angle dθn is obtained based on the radius R of the grinding wheel, and the obtained deviation angle dθn and the While obtaining new machining information (Ln, dθn, ρn, nΔθ) from the machining information (Ln, ρn, nΔθ), the actual inter-axis distance at the contact position ρj is obtained with Ln ′ as Ln + ΔL, and then V The small-diameter bevel grindstone is controlled by switching the groove bevel grindstone to the small-diameter bevel grindstone based on the deviation angle dθn instead of the bevel curve value and controlling the inter-axis distance adjusting means. A beveling process is performed on the peripheral edge of the eyeglass-shaped eyeglass lens .

In order to achieve the above-mentioned object, a lens grinding apparatus according to a second aspect of the present invention includes a carriage that moves up and down around a carriage rotation shaft at a rear portion, and a pair of lens rotation shafts that are held at the front end portion of the carriage. A grinding wheel having a radius R for grinding the periphery of an unprocessed spectacle lens held between the pair of lens rotating shafts, a V-groove beveling wheel provided on the grinding wheel, and the lens rotating shaft A small-diameter bevel grindstone that is driven forward and backward with respect to the held spectacle lens to bevel the peripheral portion of the spectacle lens, and the front end portion of the carriage is moved up and down around the turning axis to rotate the lens rotation shaft and the spectacles. Corresponding to the lens shape data (θn, ρn) of the spectacle lens and the inter-axis distance adjusting means for adjusting the inter-axis distance between the grinding wheel and the lens rotation axis by moving the lens up and down. With obtaining the processing data of the spectacle lens, the Rukoto rotates the front end portion of the operation control to the carriage the center distance adjusting means based on the processing data about said pivot axis, and the lens rotating shaft said An arithmetic control circuit for grinding the peripheral edge of the unprocessed spectacle lens into a lens shape with the grinding wheel while adjusting the distance between the axes with the grinding wheel,
When the curve value of the bevel curve of the bevel formed at the periphery of the spectacle lens processed into the target lens shape is smaller than 4 , the arithmetic control circuit uses the V-groove bevel grindstone to generate the peripheral edge of the target lens lens. When the bevel curve value is 4 or more, the bevel curve value is 4 or more, and the V-groove bevel grindstone is switched to the small-diameter bevel grindstone and the small-diameter bevel grindstone is used to bevel the peripheral portion of the lens-shaped spectacle lens. Is a lens grinding apparatus for performing beveling , wherein an interaxial distance in calculation of a moving radius ρn at a rotation angle nΔθ of the target lens shape data (ρn, nΔθ) is Ln as ρn + R, and the interaxial distance Ln. The virtual processing point of the spectacle lens in FIG. 5 is defined as Fi, and the actual contact position between the grinding wheel at the rotation angle nΔθ and the processing target lens as the raw spectacle lens is ρ. Ln ′ is the actual distance between the lens rotation axis and the grinding wheel at the actual contact position ρj, and the difference between the calculated distance Ln and the actual distance Ln ′ is When the error ΔL is set and the deviation angle between the virtual processing point Fi at the radius ρn of the rotation angle nΔθ and the contact processing point that is the actual contact position of the spectacle lens with the grinding wheel is dθn, the calculation control is performed. The circuit calculates the inter-axis distance Ln from the target lens shape data (ρn, nΔθ) [n = 0, 1, 2, 3... J] and the radius R of the grinding wheel, and determines the inter-axis distance. Machining information (Ln, ρn, nΔθ) is determined from the distance Ln and the target lens shape data (ρn, nΔθ), and the target lens shape data (ρn, nΔθ) is determined when determining the processing information (Ln, ρn, nΔθ). ) And the radius R of the grinding wheel, the deviation angle dθn is obtained, and the obtained deviation angle dθn and After obtaining new machining information (Ln, dθn, ρn, nΔθ) from the machining information (Ln, ρn, nΔθ), the actual inter-axis distance at the contact position ρj is obtained with Ln ′ as Ln + ΔL. Switching from the V-groove bevel grindstone to the small-diameter bevel grindstone is performed based on the deviation angle dθn instead of the magnitude of the bevel curve value, and the small-diameter bevel is controlled by controlling the inter-axis distance adjusting means. A beveling process is performed on the peripheral edge of the lens-shaped spectacle lens with a grindstone .

  According to this method and apparatus, the curve value of the bevel curve formed after the peripheral processing of the spectacle lens is obtained, and beveling using a tapered small-diameter bevel grindstone is performed based on the curve value. Even in the case of beveling of the periphery of a spectacle lens such as a sports spectacle frame having a very large curvature, grinding can be efficiently realized.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
<First Embodiment>
Referring to FIG. 1, a spectacle lens grinding apparatus according to the present invention is shown.

In FIG. 1, reference numeral 1 denotes a frame shape measuring device (lens shape) that reads lens shape information (θi, ρi) as lens shape data from a lens frame shape of an eyeglass frame F, its template, or a lens model (demo lens). (Data measuring device) 2 is a lens grinding device (2) for grinding eyeglass lenses (including rimless lenses) ML from a fabric lens or the like based on the lens shape data of the eyeglass frame inputted by transmission from the frame shape measuring device. Tamashiri machine). In addition, since a well-known thing can be used for the frame shape measuring apparatus 1, description of the detailed structure, a data measurement method, etc. is abbreviate | omitted.
<Lens grinding device 2>
As shown in FIG. 1, an upper surface (inclined surface) 3a that is inclined toward the front side of the apparatus body 3 is provided on the upper portion of the lens grinding apparatus 2, and at the front side (lower side) of the upper surface 3a. An opening processing chamber 4 is formed. The processing chamber 4 is opened and closed by a cover 5 attached to the apparatus body 3 so as to be slidable obliquely up and down.

  Further, on the upper surface 3 a of the apparatus main body 3, an operation panel 6 positioned on the side of the processing chamber 4, an operation panel 7 positioned on the rear side 1 from the upper opening of the processing chamber 4, and a lower side of the operation panel 7 A liquid crystal display 8 is provided which is positioned further rearward and displays an operation state by the operation panels 6 and 7.

  Further, in the apparatus main body 3, as shown in FIGS. 3 and 4, a grinding part 10 having a processing chamber 4 is provided. The processing chamber 4 is formed in a peripheral wall 11 fixed to the grinding portion 10.

  The peripheral wall 11 has left and right side walls 11a and 11b, a rear wall 11c, a front wall 11d, and a bottom wall 11e as shown in FIGS. Moreover, arcuate guide slits 11a1 and 11b1 are formed on the side walls 11a and 11b (see FIG. 3A). Further, as shown in FIG. 3A, the bottom wall 11e includes an arcuate bottom wall (inclined bottom wall) 11e1 extending in an arc shape downward from the rear wall 11c and a front lower end of the arcuate bottom wall 11e1. To the front wall 11d. The lower bottom wall 11e2 is provided with a drain pipe 11f extending close to the arc-shaped bottom wall 11e1 and extending to a lower waste liquid tank (not shown).

(Cover 5)
The cover 5 is composed of a single glass or resin panel that is colorless and transparent or colored and transparent (for example, colored and transparent such as gray), and slides forward and backward of the apparatus body 3.

(Operation panel 6)
As shown in FIG. 2A, the operation panel 6 includes a “clamp” switch 6a for clamping the spectacle lens ML with a pair of lens shafts 23 and 24, which will be described later, and the right and left eyes of the spectacle lens ML. “Left” switch 6b and “Right” switch 6c for specifying the processing for display and switching the display, “Whetstone movement” switches 6d and 6e for moving the grindstone in the left-right direction, and finishing of the spectacle lens ML are incomplete. "Refinish / Trial" switch 6f for refinishing or trial sliding when sufficient or trial 3 is slid, "lens rotation" switch 6g for lens rotation mode, and "stop" for stop mode And a switch 6h. Although not shown in the operation panel 6 in FIG. 2A, the beveling is switched from the beveling with a normal V-groove beveling grindstone (grinding grindstone) 35 to the beveling with a small-diameter beveling grindstone 200. A selection switch can be provided.

  This is to reduce the burden on the operator's operation by arranging a switch group necessary for actual lens processing at a position close to the processing chamber 4.

(Operation panel 7)
As shown in FIG. 2B, the operation panel 7 includes a “screen” switch 7a for switching the display state of the liquid crystal display 8, and a “memory” switch for storing settings relating to processing displayed on the liquid crystal display 8. 7b, a “data request” switch 7c for capturing lens shape information (θi, ρi), and a seesaw type “− +” switch 7d (“−” switch and “+” switch used for numerical correction) And a “別 々” switch 7e for moving the cursor-type pointer is arranged on the side of the liquid crystal display 8. In addition, function keys F1 to F6 are arranged below the liquid crystal display 8.

  The function keys F1 to F6 are used for setting for processing of the eyeglass lens ML, and for responding to and selecting messages displayed on the liquid crystal display 8 in the processing process.

  The function keys F1 to F6 are set for processing (layout screen). The function key F1 is used for inputting the lens type, the function key F2 is used for inputting the processing course, the function key F3 is used for inputting the lens material, and the function key F4 is used. The frame type input, function key F5 is used for chamfering type input, and function key F6 is used for mirror finishing input.

  Lens types input with the function key F1 include “single focal point”, “ophthalmic prescription”, “progressive”, “bifocal”, “cataract”, “plum”, “8 curve”, and the like. In the spectacles industry, “cataract” generally means a positive lens having a large refractive power, and “bottle” means a negative lens having a large refractive power.

  Processing courses input with the function key F2 include “auto”, “trial”, “monitor”, “frame change”, and the like. The function key F2 can be provided with a beveling selection course for switching from beveling to a normal beveling grindstone (beveling grindstone 35 of the grinding wheel 35) to beveling with a small-diameter beveling stone 200.

  The material of the lens to be processed that is input with the function key F3 includes “plastic”, “high index”, “glass”, “polycarbonate”, “acrylic”, and the like.

  The types of eyeglass frames F that can be input with the function key F4 are “metal”, “cell”, “optil”, “flat”, “groove (thin)”, “groove (medium)”, “groove”. (Thick) ”etc. Each “grooving” indicates a bevel groove which is a kind of beveling.

  Types of chamfering processing input with the function key F5 include “None”, “Small”, “Medium”, “Large”, “Special” and the like.

  Examples of the mirror finishing input with the function key F6 include “none”, “present”, “mirror chamfering”, and the like.

  The mode, type, or order of the function keys F1 to F6 described above is not particularly limited. In addition, as the selection of each tab TB1 to TB4 to be described later, the number of keys is not limited, such as providing function keys for selecting “layout”, “processing”, “processed”, “menu”, etc. Absent.

(Liquid crystal display 8)
The liquid crystal display 8 is switched by a “layout” tab TB1, a “processing” tab TB2, a “processed” tab TB3, and a “menu” tab TB4, and below the function display section H1 corresponding to the function keys F1 to F6. ~ H6. Note that the colors of the tabs TB1 to TB4 are independent, and the background background except for the areas E1 to E4, which will be described later, is the same background color as the tabs TB1 to TB4 simultaneously with the selection switching of the tabs TB1 to TB4. Switch.

  For example, the “display” tab TB1 and the entire display screen (background) with the tab TB1 are blue, the “processing” tab TB2 and the entire display screen (background) with the tab TB2 are green, The tab TB3 and the entire display screen (background) with the tab TB3 are displayed in red, and the menu screen TB4 and the entire display screen (background) with the tab TB4 are displayed in yellow.

  In this way, the tabs TB1 to TB4 color-coded for each work and the surrounding background are displayed in the same color, so that the worker can easily recognize or confirm which work is currently being performed. .

  The function display sections H1 to H6 are appropriately displayed as necessary, and when they are in the non-display state, display different symbols, numerical values, or states from those corresponding to the functions of the function keys F1 to F6. Can do.

  Further, when the function keys F1 to F6 are operated, for example, when the function key F1 is operated, the display of the mode or the like may be switched every time the function key F1 is clicked. For example, a list of each mode corresponding to the function key F1 can be displayed (pop-up display) to improve the selection operation. The list displayed in the pop-up display is represented by characters, graphics, icons, or the like.

  When the “Layout” tab TB1, the “Processing” tab TB2, and the “Processed” tab TB3 are selected, they are divided into an icon display area E1, a message display area E2, a numerical value display area E3, and a status display area E4. Is displayed. When the “menu” tab TB4 is selected, it is displayed as one menu display area as a whole. When the “Layout” tab TB1 is selected, the “Processing” tab TB2 and the “Processed” tab TB3 may not be displayed and may be displayed when the layout setting is completed.

  The layout setting using the liquid crystal display 8 as described above is the same as that in Japanese Patent Application No. 2000-287040 or Japanese Patent Application No. 2000-290864, and thus detailed description thereof is omitted.

<Grinding part 10>
As shown in FIGS. 3 and 4, the grinding unit 10 includes a tray 12 fixed to the apparatus main body 3, a base 13 disposed on the tray 12, a base drive motor 14 fixed to the tray 12, and a tray. 12 is provided with a screw shaft 15 that interlocks with an output shaft (not shown) of a base drive motor 14 that is rotatably supported at a tip by a support portion 12a (see FIG. 5) raised from 12. The grinding unit 10 includes a rotation driving system 16 for the spectacle lens ML, a grinding means 17 for the spectacle lens ML, and an edge thickness measuring system (edge thickness measuring means) 18 for the spectacle lens ML.

(Base 13)
The base 13 is formed in a substantially V shape from a rear side support portion 13a extending left and right along the rear edge portion of the tray 12 and a side side support portion 13b extending frontward from the left end portion of the rear side support portion 13a. . V block-shaped shaft support portions 13c and 13d are fixed on both right and left ends of the rear support portion 13a, and a V block-shaped shaft support portion 13e is fixed on the front end portion of the side support portion 13b. ing.

  In the apparatus main body 3, a pair of parallel guide bars 19 and 20 extending in the left-right direction and arranged in parallel in the front-rear direction are disposed. The left and right ends of the parallel guide bars 19 and 20 are attached to the left and right portions in the apparatus main body 3. In addition, the side guide portions 13b of the base 13 are pivotally supported by the parallel guide bars 19 and 20 so as to be movable back and forth in the left and right directions along the axial direction.

  Further, both end portions of the carriage turning shaft 21 extending in the left-right direction are disposed in the V-groove portions on the shaft support portions 13c and 13d. A carriage 22 is attached to the carriage turning shaft 21. The carriage 22 is provided in a continuous manner between the left and right shaft mounting arm portions 22a and 22b that are spaced apart from each other and extend in the front-rear direction and the rear end portions of the arm portions 22a and 22b that extend in the left-right direction. It is formed in a bifurcated shape from a portion 22c and a support protrusion 22d protruding rearward from the left and right center of the connecting portion 22c. The arm portions 22a and 22b and the connecting portion 22c are U-shaped. A peripheral wall 11 that forms the processing chamber 4 is disposed between the arm portions 22a and 22b.

  The carriage turning shaft 21 passes through the support protrusion 22d and is held by the support protrusion 22d, and is rotatable with respect to the shaft support portions 13c and 13d. Thereby, the front end side of the carriage 22 can be turned up and down around the carriage turning shaft 21. The carriage turning shaft 21 may be fixed to the shaft support portions 13c and 13d, and the support protrusion 22d may be held so as to be rotatable with respect to the carriage turning shaft 21 and not movable in the axial direction.

  The carriage 22 includes a pair of lens shafts (lens rotation shafts) 23 and 24 that extend from side to side and sandwich a spectacle lens (circular unprocessed spectacle lens, that is, circular processed lens material) ML on the same axis. . The lens shaft 23 penetrates the distal end portion of the arm portion 22a toward the left and right, and is held at the distal end portion of the arm portion 22a so as to be rotatable about the axis and immovable in the axial direction. The lens shaft 24 penetrates the distal end portion of the arm portion 22b toward the left and right, and is held at the distal end portion of the arm portion 22b so as to be rotatable about the axis and adjustable in the axial direction. Since this structure employs a well-known structure, a detailed description thereof will be omitted.

  Further, a guide portion 13f is formed integrally with the base 13, and a screw shaft (feed screw) 15 is screwed to the guide portion 13f. Then, by operating the base drive motor 14 and rotationally driving the screw shaft 15 with the base drive motor 14, the guide portion 13f is moved forward and backward in the axial direction of the screw shaft 15, and the base 13 is integrated with the guide portion 13f. It is supposed to move. At this time, the base 13 is guided by the pair of parallel guide bars 19 and 20 and displaced along the axial direction.

[Carriage 22]
The above-described guide slits 11 a 1 and 11 b 1 of the peripheral wall 11 are formed in an arc shape around the carriage turning shaft 21. End portions of the lens shafts 23 and 24 held by the carriage 22 are inserted into the guide slits 11a1 and 11b1. As a result, the opposite end portions of the lens shafts 23, 24 protrude into the processing chamber 4 surrounded by the peripheral wall 11.

  Further, as shown in FIG. 3A, an arcuate and hat-shaped guide plate P1 is attached to the inner wall surface of the side wall portion 11a, and the inner wall surface of the side wall portion 11b is circular as shown in FIG. An arc-shaped and hat-shaped guide plate P2 is attached. The guide plates P1, P2 are formed with guide slits 11a2 ', 11b2' extending in an arc shape corresponding to the guide slits 11a1, 11b1.

  A cover plate 11a2 for closing the guide slits 11a1 and 11a2 'is disposed between the side wall portion 11a and the guide plate P1 so as to be movable back and forth and up and down, and between the side wall portion 11b and the guide plate P2. The cover plate 11b2 that closes the guide slits 11b1 and 11b2 'is arranged to be movable back and forth and up and down. Further, the lens shafts 23 and 24 penetrate the cover plates 11a2 and 11b2 slidably. Accordingly, the cover plates 11a2 and 11b2 are attached to the lens shafts 23 and 24 so as to be relatively movable in the axial direction.

  Moreover, the guide plate P1 is provided with arcuate guide rails Ga and Gb that are positioned above and below the guide slits 11a1 and 11a2 ′ and along the upper and lower edges of the guide slits 11a1 and 11a2 ′, and the guide plate P2 has the guide slit 11b1. , 11b2 ′ are provided with arcuate guide rails Gc, Gd along the upper and lower edges of the guide slits 11b1, 11b2 ′, and the cover plate 11a2 is guided up and down by the guide rails Ga, Gb in an arcuate shape. It can be moved up and down. The cover plate 11b2 is guided up and down by the guide rails Gc and Gd and can move up and down in an arc shape.

  The lens shaft 23 of the carriage 22 slidably penetrates the arc-shaped cover plate 11a2, and the assembly of the lens shaft 23, the side wall portion 11a1, the guide plate P1, and the cover plate 11a2 is improved, and the lens shaft 24 of the carriage 22 is improved. Slidably penetrates the arc-shaped cover plate 11b2 to improve the assemblability of the lens shaft 24, the side wall portion 11b1, the guide plate P2, and the cover plate 11b2.

  Further, the cover plate 11a2 and the lens shaft 23 are sealed with a seal member Sa, and the cover plate 11a2 is held on the lens shaft 23 with seal members Sa and Sa. Further, the space between the cover plate 11b2 and the lens shaft 24 is sealed through a seal member Sb, and the cover plate 11b2 is held on the lens shaft 24 through the seal members Sb and Sb so as to be relatively movable in the axial direction. ing. As a result, when the lens shafts 23 and 24 are pivoted up and down along the guide slits 11 a 1, 11 a 2 ′ and 11 b 1, 11 b 2 ′, the cover plates 11 a 2, 11 b 2 can also move up and down integrally with the lens shafts 23, 24. .

  The seal member Sa is held by the cover plate 11a2, or the peripheral portion is disposed between the cover plate 11a2 and the side wall portion 11a and between the cover plate 11a2 and the guide plate P1, so that the lens shaft 23 is disposed. May move in the axial direction of the lens shaft 23 when the lens moves in the axial direction. Similarly, the seal member Sb is held by the cover plate 11b2, or the peripheral portion is disposed between the cover plate 11b2 and the side wall portion 11b and between the cover plate 11b2 and the guide plate P2, so that the lens When the shaft 24 moves in the axial direction, it may be prevented from moving in the axial direction of the lens shaft 24.

  The side wall 11a1 and the guide plate P1 are close to each other so as to be in close contact with the arc-shaped cover plate 11a2, and the side wall 11b1 and the guide plate P2 are close to each other so that the arc-shaped cover plate 11b2 is in close contact with each other.

  Further, the guide plates P1 and P2 in the processing chamber 4 extend to the vicinity of the rear side wall 11c and the lower bottom wall 11e2, so that the upper and lower ends are cut around the side of the feeler 41 and the upper vicinity of the grinding wheel 35. By opening the upper and lower ends of the guide plates P1 and P2 into the processing chamber 4 so that the grinding fluid flows along the inner surfaces of the side wall portions 11a1 and 11b1, the side wall portions 11a1 and the guide plate P1 are provided. And the grinding liquid does not accumulate between the side wall 11b1 and the guide plate P2.

  When the carriage 22 is rotated up and down around the carriage turning shaft 21 and the lens shafts 23 and 24 are moved up and down along the guide slits 11a1 and 11b1, the cover plates 11a2 and 11b2 are also moved up and down integrally with the lens shafts 23 and 24. The guide slits 11a1 and 11b1 are always closed by the cover plates 11a2 and 11b2 so that the grinding fluid in the peripheral wall 11 does not leak to the outside of the peripheral wall 11. The eyeglass lens ML approaches and separates from the grinding wheel 35 as the lens shafts 23 and 24 move up and down.

  When the eyeglass lens ML is attached to the lens shafts 23 and 24 such as a fabric lens and when the spectacle lens ML is detached after the grinding process is finished, the carriage 22 is moved up and down so that the lens shafts 23 and 24 are positioned at an intermediate position of the guide groove 11a. It is positioned at the rotational center of the direction. The carriage 22 is tilted by being controlled to rotate up and down according to the amount of grinding of the spectacle lens ML at the time of edge thickness measurement and grinding (the rotation drive system 16 of the lens shafts 23 and 24).

  The rotation drive system 16 of the lens shafts 23 and 24 includes a lens shaft driving motor 25 fixed to the carriage 22 by fixing means (not shown), and an output of the lens shaft driving motor 25 that is rotatably held by the carriage 22. A power transmission shaft (drive shaft) 25a that is linked to the shaft, a drive gear 26 provided at the tip of the power transmission shaft 25a, and a driven gear 26a that meshes with the drive gear 26 and is attached to one lens shaft 23. . In FIG. 8, a worm gear is used for the drive gear 26 and a worm wheel is used for the driven gear 26a. A bevel gear (bevel gear) can be used for the drive gear 26 and the driven gear 26a.

  Furthermore, the rotational drive system 16 includes a pulley 27 fixed to the outer end of one lens shaft 23 (the end opposite to the lens shaft 24), a power transmission mechanism 28 provided on the carriage 22, A pulley 29 is rotatably provided at the outer end of the other lens shaft 24 (the end opposite to the lens shaft 23). The pulley 29 is provided so as to be relatively movable in the axial direction with respect to the lens shaft 24, and is arranged on the carriage 22 so that the position in the axial direction does not change when the lens shaft 24 is moved and adjusted in the axial direction. The movement is restricted by a provided movement restriction member (not shown).

  The power transmission mechanism 28 includes transmission pulleys 28a and 28b and transmission shafts (power transmission shafts) 28c in which the transmission pulleys 28a and 28b are fixed to both ends. The transmission shaft 28c is disposed in parallel with the lens shafts 23 and 24, and is rotatably held on the carriage 22 by a bearing (not shown). Further, the power transmission mechanism 28 includes a drive side belt 28d spanned between the pulley 27 and the transmission pulley 28a, and a driven side belt 28e spanned between the pulley 29 and the transmission pulley 28b. Yes.

When the lens shaft driving motor 25 is operated to rotate the power transmission shaft 25a, the rotation of the power transmission shaft 25a is transmitted to the lens shaft 23 through the driving gear 26 and the driven gear 26a, and the lens shaft 23 and the pulley 27 are rotated. Are rotated together. On the other hand, the rotation of the pulley 27 is transmitted to the pulley 29 via the drive side belt 28d, the transmission pulley 28a, the transmission shaft 28c, the transmission pulley 28b, and the driven side belt 28e, and the pulley 29 and the lens shaft 24 are integrally rotated. The At this time, the lens shaft 24 and the lens shaft 23 are rotated integrally with each other.
(Grinding means 17)
The grinding means 17 includes a grinding wheel drive motor 30 fixed to the tray 12, a transmission shaft 32 to which the drive of the grinding wheel drive motor 30 is transmitted via the belt 31, and a grinding wheel shaft portion 33 to which the rotation of the transmission shaft 32 is transmitted. And a grinding wheel 35 fixed to the grinding wheel shaft portion 33. The grinding wheel 35 includes a rough grinding wheel, a beveling wheel, a finishing grindstone, etc., whose reference numerals are omitted. The rough grinding wheel, the bevel wheel, and the finishing wheel are arranged in parallel in the axial direction. The bevel grindstone provided on the grinding grindstone 35 is a normal bevel grindstone and has a diameter of about 100 to 120 mm, for example.

  The grinding means 17 includes a rotating arm drive motor 36 fixed to the apparatus main body 3, a worm gear 36a fixed to the output shaft, a cylindrical shaft worm 37 rotatably held on the peripheral wall 11, A hollow rotating arm 38 that is integrally fixed to the worm 37, and in FIG. 5 (a), one end of the rotating arm 38 is rotatably held at the free end of the rotating arm 38 and to the right from the free end. A rotating shaft 39 projecting toward the rotating shaft 39 and a grooving grindstone 40 fixed to the rotating shaft 39 are provided.

  The grinding means 17 is attached to the peripheral wall 11 and an output shaft (not shown) is inserted into the cylindrical worm shaft 39a. The grinding means 17 is disposed in the rotating arm 38 and rotates the output shaft of the drive motor 39a. Is transmitted to the rotating shaft 39.

  The groove grindstone 40 includes chamfering grindstones 40a and 40b for chamfering the peripheral edge of the spectacle lens ML as shown in FIGS. 3A and 4, and a rotating shaft 39 adjacent to the chamfering grindstone 40a. Has a grooving cutter 40c attached to the. In addition, an arcuate cover 38a that extends to the right in FIG. The arc-shaped cover 38a covers the lower portions of the chamfering grindstones 40a and 40b and the grooving cutter 40c.

  7 to 8, another embodiment of the grinding means 17 is shown. In this embodiment, the grinding means 17 includes a tapered and small-diameter bevel grindstone 200 and a rotating arm 500 that supports the small-diameter bevel grindstone 200 and tilts the small-diameter bevel grindstone 200 with respect to the spectacle lens. Have As shown in FIG. 7, the rotating arm is attached to the side wall 11a so as to be able to swing and rotate. The grinding means 17 also has a rotation drive means 503 for rotating the small-diameter beveling stone 200, and a swing drive means 504 for swinging the rotating arm.

  More specifically, the rotating arm 500 is disposed in the processing chamber 4 of the lens processing apparatus, and has a space 505 formed by hollowing out one side as shown in FIG. 506 is fixed to one end of the cylindrical body 507. The cylindrical body 507 is rotatably supported by the side wall 11a and the wall 510 in the apparatus body 3 via bearings 508 and 509, respectively.

  The rotation drive unit 503 includes, for example, a motor 511 fixed to the wall 510 and a transmission unit for transmitting the drive of the motor to the small-diameter bevel grindstone 200. This transmission means has, for example, a drive pulley 513 fixed to the drive shaft 512 of the motor 511 and a driven pulley 515 connected to the drive pulley via a belt 514.

  The motor drive shaft 512 extends into the space 505 of the rotating arm 500 through the cylindrical body 507 and is rotatably supported by the cylindrical body 507 via a bearing 516. The drive pulley 513 is disposed in the space 505 of the rotating arm 500 and is fixed to the drive shaft 512.

  The driven pulley 515 is fixed to a support shaft (rotary shaft) 518 that is rotatably supported by the other end of the rotating arm 500, that is, the swing end 517. The support shaft 518 is rotatably attached to the rotating arm 500 by a bearing 519. In addition to the small-diameter bevel grindstone 200 described above, a grindstone 520 such as a chamfering grindstone 520a, 520b or a grooved grindstone 520c for grinding a spectacle lens is attached to the support shaft 518.

  The small-diameter bevel grindstone 200 has a tapered surface 200a and a V-groove 200b formed on the tapered surface 200a and extending annularly in the circumferential direction. Further, the diameter of the small-diameter bevel grindstone 200 is preferably the same as or smaller than the diameter of the chamfering grindstone 520a, 520b or the grooving grindstone 520c, for example, the same as 24 mm (diameter of the chamfering grindstone 520a, 520b). The size is about or smaller. The size of the grooving grindstone 520c is 17.6 mm.

  Moreover, in order to reduce processing interference, the smaller the diameter of the bevel wheel 200 is better, but there are problems such as processing pressure and processing time. Therefore, the above-described size wheel is desirable.

  For example, if the curve value of the bevel curve is 3 curves, beveling is performed using a normal bevel grindstone. If the curve is 4 curves or more (for example, +8 curve), the small diameter set on the support shaft (chamfering grindstone shaft) 518 is used to bevel.

  A small-diameter cylindrical bevel grindstone and a tapered bevel grindstone may be arranged in parallel, and the bevel grindstone may be properly used according to the curve value of the bevel curve. For example, in the case of the 7-8 curve having the largest degree of curvature, the small-diameter tapered bevel grindstone is used, and in the case of the 4-6 curve having a small degree of curvature, the small-diameter cylindrical bevel grindstone is used. Also good.

  Further, the belt 514 and the driven pulley 515 are disposed in the space 505 of the rotating arm. The space 505 of the rotating arm 500 is closed by a cover 527. A part of the grindstone 520 is covered by a substantially semicircular cover 528 (see FIG. 8).

  Here, when the motor 511 is rotated, the drive pulley 513 is rotated, the driven pulley 515 is rotated via the belt 514, and the support shaft 518 is rotated. As a result, the grindstones 200 and 520 are rotated.

  As shown in FIG. 7, the swing driving means 504 includes a motor (driving means) 531 fixed to the wall 510 and a transmission means for transmitting the driving of the motor to the rotating arm. This transmission means includes a gear 533 fixed to the drive shaft 532 of the motor 531 and a gear 534 engaged with the gear. The gear 534 is fixed to the cylindrical body 507. Accordingly, when the motor 531 is rotated, the cylindrical body 507 is rotated via the gears 533 and 534, and then the rotating arm 500 fixed to the cylindrical body is swung. Thereby, the grindstones 200 and 520 can be brought into contact with or separated from the spectacle lens 203.

<Center distance adjusting means 43>
As shown in FIG. 1, the distance between the lens shafts 23 and 24 and the grindstone shaft portion 33 is adjusted by an inter-axis distance adjusting means (inter-axis distance adjusting mechanism) 43.

  The inter-axis distance adjusting means 43 has a rotating shaft 34 whose axis is located on the same axis as the grindstone shaft 33. The rotary shaft 34 is rotatably supported on the V groove of the support protrusion 13e shown in FIG.

  The inter-axis distance adjusting means 43 includes a base board 56 held by the rotary shaft 34, a pair of parallel guide rails 57, 57 attached to the base board 56 and extending obliquely upward from the upper surface, A screw shaft (feed screw) 58 provided on the base board 56 so as to be parallel and rotatable, a pulse motor 59 provided on the lower surface of the base board 56 to rotate the screw shaft 58, and the screw shaft 58 are screwed. A receiving base 60 (not shown for convenience of illustration of other portions in FIG. 2) is provided on the guide rails 57, 57 so as to be movable up and down.

  Furthermore, the inter-axis distance adjusting means 43 holds the upper end of the guide rails 57 and 57, the lens shaft holder 61 disposed above the pedestal 60 and held on the guide rails 57 and 57 so as to be movable up and down. A reinforcing member 62 that rotatably holds the upper end portion of the screw shaft 58 is provided. The lens shaft holder 61 is always urged downward and pressed against the cradle 60 by the weight of the carriage 22 and the spring force of the spring 54 of the pressure adjusting mechanism 45. In addition, a sensor S that detects that the lens shaft holder 61 has come into contact with the pedestal 60 is attached.

  When the pedestal 60 is raised or lowered along the guide rails 57 and 57 by the screw shaft 58 by rotating the pulse motor 59 forward or backward to rotate the screw shaft 58 forward or backward, the lens shaft holder 61 is raised or lowered together with the cradle 60. As a result, the carriage 22 rotates about the carriage turning shaft 21.

<Edge thickness measuring system 18>
An edge thickness measuring system (lens edge thickness measuring device, edge thickness measuring means) 18 as a lens shape measuring device is disposed at the upper rear edge of the processing chamber 4 as shown in FIGS. A measuring element 41, a measuring axis 42a provided in parallel with the lens axes 23 and 24 and having one end integrated with the measuring element 41, and an outer side of the side wall 11b are disposed close to the upper part of the rear edge side and disposed outside the processing chamber 4. The measurement unit (measurement element movement amount detection unit) 42 is provided. The measuring shaft 42a penetrates the side wall 11b and protrudes into and out of the processing chamber 4.
(Measuring element 41)
As shown in FIGS. 3A and 4, the measuring element 41 has a feeler holding member 100 and a pair of feelers 101 and 102. The feeler holding member 100 includes a continuous portion 100a extending in the left-right direction and parallel opposing pieces 100b and 10c projecting in the same direction at both left and right ends of the continuous portion 100a. Further, the feelers 101 and 102 are formed in a columnar shape and are attached to face the tip portions of the facing pieces 100b and 100c.

  Further, the feeler holding member 100 is attached to a measuring shaft 42a extending through the side wall 11b and extending left and right as shown in FIG. The measuring shaft 42a is held by a measuring unit 42 disposed outside the side wall 11b so as to be movable left and right. And this measurement part 42 detects the movement amount to the left and right of the feeler holding member 100 via the measurement axis 42a.

(Control circuit)
The above-described operation panels 6 and 7 (that is, the switches of the operation panels 6 and 7) are connected to an arithmetic control circuit (arithmetic control means, arithmetic means) 80 having a CPU as shown in FIG. The arithmetic control circuit 80 is connected to a ROM 81 as a storage unit, a data memory 82 as a storage unit, and a RAM 83, and a correction value memory 84.

  Furthermore, the liquid crystal display 8 is connected to the arithmetic control circuit 80 via a display driver 85, and a pulse motor driver (pulse motor drive circuit) 86 is connected. The pulse motor driver 86 is controlled by an arithmetic control circuit 80 to control various drive motors of the grinding unit 10, that is, the base drive motor 14, the lens shaft drive motor 25, the rotating arm drive motor 36, the moving element displacement. The motor 48 and the pulse motor 59 are controlled to operate (drive control). A pulse motor is used for the base drive motor 14, the lens shaft drive motor 25, the rotating arm drive motor 36, the mover displacement motor 48, and the like.

  Furthermore, the grindstone drive motor 30 or 511 is connected to the arithmetic control circuit 80 via a motor driver (motor drive circuit) 86a, and the grindstone drive motor 39a is connected via a motor drive (motor drive circuit) 86b. . The motor drive circuit 86b has a current detection circuit (current detection means, current detection means) 86b1 for detecting the current flowing through the grindstone drive motor 39a. The detected current from the current detection circuit 86b1 is input to the arithmetic control circuit 80.

Further, the frame shape measuring apparatus 1 of FIG. 1 is connected to the arithmetic control circuit 80 via the communication port 88, and the frame shape data, lens shape data, etc. from the frame shape measuring apparatus (lens shape measuring apparatus) 1 are connected. The target lens shape data is input as radius vector information .

  In addition, a movement amount detection signal from the measurement unit 42 is input to the arithmetic control circuit 80.

  The arithmetic control circuit 80 includes a lens shaft driving motor 25, a pulse motor 59, and the like that are operation-controlled based on the driving pulse of the base driving motor 14 and the target lens shape data (θi, ρi) from the frame shape measuring apparatus 1. From the driving pulse and the movement amount detection signal from the measuring unit 42, the coordinate position and rear of the front refractive surface (the left surface of the spectacle lens in FIG. 4) of the spectacle lens ML in the target lens shape data (θi, ρi). The coordinate position of the side refracting surface (the right side surface of the spectacle lens in FIG. 4) is obtained, and the coordinate position of the front refracting surface of the spectacle lens ML and the rear side refraction in the obtained lens shape data (θi, ρi). The edge thickness Wi is obtained by calculation from the coordinate position of the surface.

  The arithmetic control circuit 80 performs time-sharing processing when there is data reading from the frame shape measuring apparatus 1 or data stored in the storage areas m1 to m8 of the data memory 82 after the start of processing control. Controls data reading and layout settings.

  That is, if the period between times t1 and t2 is T1, the period between times t2 and t3 is T2, the period between times t3 and t4 is T3,..., And the period between times tn-1 and tn is Tn. Control is performed between periods T1, T3,... Tn, and data reading and layout setting are controlled during periods T2, T4,. Therefore, during the grinding of the lens to be processed, the next plurality of target lens shape data can be read and stored, the data can be read and the layout can be set (adjusted), and the data processing efficiency can be greatly improved. Be able to.

  The ROM 81 described above stores various programs for controlling the operation of the lens grinding apparatus 2, and the data memory 82 is provided with a plurality of data storage areas. Further, the RAM 83 is provided with a machining data storage area 83a for storing machining data currently being machined, a new data storage area 83b for storing new data, and a data storage area 83c for storing frame data, processed data, and the like. ing.

  As the data memory 82, a readable / writable FEEPROM (flash EEPROM) can be used, or a RAM using a backup power source that prevents the contents from being erased even when the main power is turned off can be used.

  Further, the arithmetic control circuit 80 controls the operation of bringing the grindstones 200 and 520 closer to or away from the spectacle lens.

  Further, the arithmetic control circuit 80 includes a lens processing data memory, a correction table memory (correction data memory), a reference rotation speed memory for the lens rotation axis, a shape information memory, a shaft distance memory, and a deviation angle memory. It is connected.

Next, the function of the arithmetic control circuit 80 described above will be described together with the operation.
(1) Calculation of lens periphery processing data (lens shape data) (i). Eyeglass lens shape measurement After turning on the power, the switch is operated and the lens frame shape of the eyeglass frame (eyeglass frame) F (lens shape of the eyeglass lens framed in the lens frame) or the rimless frame ball plate (or Glasses lens shape measurement mode such as the shape of the template (glass lens shape) is set. On the other hand, the spectacle frame F or the target lens shape is set at a predetermined position, and the measurement start switch is pressed to start measurement.

  Thus, the arithmetic control unit 80 controls the operation of the drive controller and generates a drive pulse from the pulse generator, thereby operating the pulse motor with this pulse to rotate the rotating arm. Thereby, the feeler is moved along the inner periphery of the lens frame RF or LF of the spectacle frame F (spectacle frame).

At this time, the movement amount of the above-described feelers 101 and 102 is detected by the encoder and inputted to the frame data memory (glasses lens shape data memory) as the radial length ρn, and the same pulse as that supplied from the pulse generator to the pulse motor rotates. The rotation angle of the arm, that is, the radial angle nΔθ is input to the frame data memory. In addition, the moving radius ρn and the moving radius nΔθ are stored in the frame memory as eyeglass shape data (ρn, nΔθ) [where n = 0, 1, 2, 3... It is supposed to be done. In this embodiment, i is set to 1,000, and the rotation angle Δθ is set to 0.36 ° which is 1/1000 (360 ° / 1,000) of one rotation.
(ii). Calculation of the deviation angle dθn The calculation control circuit 80 is obtained by processing the lens shape data (ρn, nΔθ), which is the spectacle lens shape data in the polar coordinate format for lens peripheral processing measured by the spectacle lens (spectacle lens) shape measuring unit 461 . From the radius of curvature R of the grinding wheel, a deviation angle dθn between the virtual machining point at the moving radius ρn of the rotation angle nΔθ and the actual contact processing point of the lens to be processed (glass lens) at the rotation angle nΔθ to the grinding wheel is predetermined. Obtain according to the flow.

Step 1:
The shape of the eyeglass lens, that is, the moving radius, of the lens frame F of the frame or a template imitated from the lens frame F by the frame shape measuring unit (frame shape measuring device) 46 as a frame shape measuring means The target lens shape data (ρn, nΔθ) (n = 1, 2, 3,... N) is obtained, and this information is stored in the frame data memory 83.

Step 2:
Based on the target lens shape data (ρn, nΔθ) from the frame data memory 83, the target lens shape data (ρ0, 0Δθ) is obtained.
Step 3:
The distance between the axes O2 of the lens rotation axes 16 and 17 and the rotation axis O1 of the grinding wheel 6 when machining the radius is used as the maximum radius vector information (ρ0, 0Δθ) as L0 (see FIG. 7).

  Here, L0 is obtained as L0 = ρ0 + R from the known grinding wheel radius R and the radial length ρ0. Further, the machining information (L0, ρ0, 0Δθ) is input to the memory 108 and stored.

  Step 4: Next, when the lens LE is rotated by the unit rotation angle Δθ, the inter-axis distance L1 at the processing point F0 at which the moving radius of the maximum moving radius length ρ0 contacts the grinding wheel 6 is obtained. Where L1 is

として求められる。

As required.

  Step 5: With the maximum radius ρ0 positioned at the machining point F0, based on the radius information (ρn, nΔθ) in the frame data memory 102, the radius information from the maximum radius to a predetermined I-th radius ( In order to obtain the virtual machining points F1, F2,..., Fi,..., of ρ1, 1Δθ), (ρ2, 2Δθ),... (ρi, iΔθ),. R, R2,... Ri,.

  Step 6: The radius R of the actual grinding wheel 6 is compared with the radius Ri (i = 1, 2, 3,... I) obtained in Step 5 above. If R ≦ Ri, even if lens grinding is performed based on the maximum radius (ρ0, 0Δθ) 1 at the machining point F0, virtual machining points Fi (i = 1, 2, 3,..., I,. Since there is no contact between I) and the grinding wheel 6, it is determined that the deviation angle dθi does not occur and “grinding wheel interference” does not occur, and the processing information (L1, ρ1, 1Δθ) at this time is determined in step 10. The data is input to the memory 108 and stored, and then the process proceeds to step 11. If R> Ri, the process proceeds to step 7.

  Step 7: When it is determined in step 6 that R> Ri, a deviation angle dθi due to “grinding wheel interference” occurs at the virtual machining point Fi. In this case, an inter-axis distance L1 (Fi) for machining a virtual (interference) machining point Fi with a grindstone having a radius R,

から求める（図１０参照）。

(See FIG. 10).

  Step 8: Predetermined in the same manner as in Step 5 with reference to the machining point Fi to be machined at the inter-axis distance L1 (Fi) obtained in Step 7. The respective virtual machining points are obtained for the radial radius up to the I-th, and the respective virtual grinding wheels Ri (Fi) are obtained.

  Step 9: Similar to Step 6, the grindstone radius R in the case of the inter-axis distance L1 (Fi) is compared with the virtual grindstone radius Ri (Fi) in Step 8. If R≤Ri (Fi), the process proceeds to step 10. If R> Ri (Fi), the process returns to step 7 in order to obtain the interaxial distance at the new interference point “ζ”.

  Step 10: When R ≦ Ri (Fi) in Step 9, machining information (L1 (Fi), ρ1, 1Δθ) is input to the memory 108 and stored.

  Step 11: Check whether or not “grinding stone interference” occurs in the radial information of (ρ1, 1Δθ) by the above-described Steps 3 to 10, and if it is determined to occur, machining information that does not generate it (L1, ρ1, 1Δθ) or (L1 (Fi), ρ1, 1Δθ) is obtained. Subsequently, steps 3 to 10 are executed for the next moving radius (ρ2, 2Δθ), and these steps are also executed for the remaining total moving radius.

  Step 12: nΔθ = 360 °, that is, whether or not the deviation angle dθn (n = 0, 1, 2, 3,... I,. It is determined whether or not machining information (Ln, ρn, nΔθ) that does not generate this is obtained. The machining information (Ln, ρn, nΔθ) obtained in this way is stored in the memory 108.

  Further, when calculating the machining information (Ln, ρn, nΔθ) in this way, the arithmetic control circuit 80 obtains the deviation angle dθn, and stores the obtained deviation angle dθn in the deviation angle memory in the machining information (Ln, dθn, ρn). , NΔθ).

Calculated deviation angle dθn
Based on this, the beveling with a normal V-groove beveling wheel is switched to the beveling with a small-diameter beveling wheel. For this switching, a bevel wheel switching switch (beveling selection switch) or the like may be provided on the operation panel 6 or the liquid crystal display 8, or the bevel wheel may be automatically switched.
(2). Actual distance between axes Ln '
(I). Axis Distance In a normal ρL (radial radius ρ−interaxial distance L) conversion method, as shown in FIGS. 10 and 11, the grinding wheel 6 and the lens LE to be processed at the radius ρn with respect to the angle θi = nΔθ The inter-axis distance Ln is calculated by calculation. When there is a deviation angle dθn, the contact position between the grinding wheel 6 and the lens LE to be processed is shifted from the angle θi = nΔθ by the deviation angle dθn, and the moving radius of the contact position is calculated. Becomes ρj. In this case, the calculated inter-axis distance Ln at the angle nΔθ has an error of ΔL with respect to the actual inter-axis distance Li ′. Assuming that the moving radius at the contact angle τn at this time is ρn, when there is a deviation angle dθn at the angle nΔθ, the actual inter-axis distance Ln ′ at which the processing lens LE should be processed by the grinding wheel 6 is
Ln ′ = Ln + ΔL
As required.

  Based on the actual inter-axis distance Ln ′ thus determined, a small-diameter bevel grinding wheel 200 installed on the rotating arm 500 is used in place of a normal V-groove beveling grinding wheel during beveling.

The arithmetic control circuit 80 described above drives and controls the rotating arm 500 so that the small-diameter bevel grinding wheel 200 is disposed at the position of the actual inter-axis distance Ln ′ (= Ln + ΔL) where the lens LE to be processed is to be processed.
(Function)
Next, the operation of the spectacle lens grinding apparatus having the above-described configuration will be described.
<Reading lens shape data, which is lens shape data>
When the main power supply is turned on from the start standby state, the arithmetic control circuit 80 determines whether or not data is read from the frame shape measuring apparatus 1.

That is, the arithmetic control circuit 80 determines whether or not the “data request” switch 7 c on the operation panel 6 has been pressed. If the “data request” switch 7 c is pressed and there is a data request, the lens shape information (θ2, ρi) data is read from the frame shape measuring apparatus 1 into the data reading area 83 b of the RAM 83. The read data is stored (recorded) in one of the storage areas m1 to m8 of the data memory 82, and a layout screen is displayed on the liquid crystal display 8.
(Calculation of processing data)
Next, the arithmetic control circuit 80 controls the operation of the measuring unit 42 to bring the feeler 101 into contact (contact) with the front refractive surface of the spectacle lens (lens to be processed) ML, and the target lens shape data (θi, ρi). ) Based on the target lens shape data (θi, ρi) by controlling the operation of the lens shaft driving motor 25 and the pulse motor 59 based on the lens shape data (θi, ρi). Let At this time, the feeler 101 is moved left and right according to the curvature of the front refracting surface, and the amount of movement to the left and right is measured by the measurement unit 42 via the measurement shaft 42a. The measurement signal from the measurement unit 42 is input to the calculation control circuit 80. The calculation control circuit 80 determines the front refractive surface of the spectacle lens ML in the target lens shape data (θi, ρi) based on the measurement signal from the measurement unit 42. Find the coordinate position.

  Similarly, the arithmetic control circuit 80 controls the measurement unit 42 to bring the feeler 102 into contact (contact) with the front refractive surface of the spectacle lens (lens to be processed) ML, and the lens shape data (θi, ρi). By controlling the operation of the lens shaft driving motor 25 and the pulse motor 59 based on this, the feeler 102 and the rear refractive surface of the spectacle lens ML are relatively contacted and moved based on the target lens shape data (θi, ρi). Let

  At this time, the feeler 101 is moved left and right according to the curvature of the rear refracting surface, and the amount of movement to the left and right is measured by the measurement unit 42 via the measurement shaft 42a. The measurement signal from the measurement unit 42 is input to the calculation control circuit 80. The calculation control circuit 80 is based on the measurement signal from the measurement unit 42 and the rear refractive surface of the spectacle lens ML in the target lens shape data (θi, ρi). Find the coordinate position of.

  A specific method disclosed in Japanese Patent Application No. 2001-30279 can be adopted as a specific method for determining the coordinate position of the front refracting surface and the coordinate position of the rear refracting surface, and detailed description thereof will be omitted.

  Then, the edge thickness Wi is obtained by calculation from the coordinate position of the front refractive surface and the coordinate position of the rear refractive surface of the eyeglass lens ML in the obtained lens shape data (θi, ρi). Further, the arithmetic control circuit 80 can be provided with an appropriate bevel curve setting device described in, for example, Japanese Patent Application Laid-Open No. 11-42543, and at least any arbitrary selected from the target lens shape data (θi, ρi). The bevel apex positions to be divided at different edge division ratios determined in advance from combinations of the edge thickness data Wi at two locations, the selected target lens shape data (θi, ρi), and the selected edge thickness data Wi. The bevel curve of the spectacle lens can be obtained.

  Normally, the bevel curve can be set in a range of less than 4 and can be framed in a spectacle frame with a good appearance. However, in the case of a spectacle frame having a small, horizontally long crab shape, the curve is 6 or more (for example, 8), and the beveling process cannot be performed well with the normal V-groove bevel grindstone of the grinding grindstone 35.

  Therefore, when the bevel curve of the spectacle lens is determined to be 4 or more, the arithmetic control circuit 80 is configured to switch from the bevel processing by the normal V groove bevel grindstone of the grinding wheel 35 to the bevel processing by the small diameter bevel grindstone 200. Depending on the size, the bevel wheel can be selectively switched by a switch or the bevel wheel can be automatically switched.

Thereafter, the arithmetic control circuit 80 determines the lens shape data (θi, ρi) from the data such as the inter-pupil distance PD and the frame geometric center distance FPD based on the prescription of the spectacle lens, the amount of uplift, and the like. ) Corresponding to the spectacle lens ML is obtained and stored in the processing data storage area 83a.

(Grinding)
Thereafter, the arithmetic control circuit 80 controls the operation of the grinding wheel driving motor 30 or 511 by the motor driver 86a, and rotationally controls the grinding wheel 35 or 200, 520 in the clockwise direction in FIG. As described above, the grinding wheel 35 includes a rough grinding wheel (flat grinding wheel), a beveling wheel, a finishing wheel, and the like.

  On the other hand, the arithmetic control circuit 80 drives and controls the lens axis driving motor 25 via the pulse motor driver 86 based on the processing data (θi ′, ρi ′) stored in the processing data storage area 83a, and the lens rotation axis. 23 and 24 and the spectacle lens ML are controlled to rotate counterclockwise in FIG.

  At this time, the arithmetic control circuit 80 first controls the operation of the pulse motor driver 86 at a position of i = 0 based on the machining data (θi ′, ρi ′) stored in the machining data storage area 83a, thereby controlling the pulse motor. 59 is driven and controlled, the screw shaft 58 is reversed, and the cradle 60 is lowered by a predetermined amount. As the cradle 60 is lowered, the lens shaft holder 61 is lowered integrally with the cradle 60 under the weight of the carriage 22 and the adjustment of the processing pressure adjusting mechanism.

  With this lowering, after the unprocessed circular spectacle lens ML contacts the grinding surface 35a of the grinding wheel 35, only the cradle 60 is lowered. When the cradle 60 moves downward from the lens shaft holder 61 due to this lowering, this separation is detected by the sensor S, and a detection signal from the sensor S is input to the arithmetic control circuit 80. After receiving the detection signal from the sensor S, the arithmetic control circuit 80 further drives and controls the pulse motor 59 to slightly lower the cradle 60 by a predetermined amount.

  As a result, the grinding wheel 35 grinds the spectacle lens ML by a predetermined amount when the processing data (θi ′, ρi ′) is i = 0. When the lens shaft holder 61 is lowered and comes into contact with the pedestal 60 along with this grinding, the sensor S detects this and outputs a detection signal, and this detection signal is input to the arithmetic control circuit 80.

  Upon receiving this detection signal, the arithmetic control circuit 80 causes the spectacle lens ML to be ground by a grinding wheel as if i = 0 in the machining data (θi ′, ρi ′). Then, the arithmetic control circuit 80 performs such control as i = n (360 °), and the spectacle lens ML is controlled so that the moving radius ρi ′ is obtained for each angle θi ′ of the processing data (θi ′, ρi ′). The peripheral edge is ground by a rough grinding wheel with the reference numeral of the grinding wheel omitted.

  In such grinding, the arithmetic control circuit 80 discharges the grinding fluid from the grinding fluid supply device.

<Beveling>
When the spectacle lens ML is ground in order to enclose the spectacle lens ML in the lens frame of the spectacle frame, the arithmetic control circuit 80 is a bevel grindstone in which the reference numeral of the grindstone is omitted in substantially the same manner as the above grinding. A beveling process is performed on the peripheral edge of the spectacle lens ML that has been roughly ground into a shape of (θi ′, ρi ′). The machining data (θi ′, ρi ′) indicates the machining radius ρi ′ at the rotation angle θi ′ (i = 0, 1, 2,... N) of the lens shafts 23, 24. Further, the arithmetic control circuit 80 automatically switches from the beveling with the normal V-groove beveling grindstone of the grinding wheel 35 to the beveling with the small-diameter beveling stone 200 based on the obtained deviation angle dθn.

  Alternatively, the arithmetic control circuit 80 receives a signal from a bevel grinding wheel changeover switch (beveling selection switch) or the like, and switches from beveling with a normal V-groove beveling grindstone of the grinding wheel 35 to beveling with a small-diameter beveling stone 200.

  Further, when the bevel curve of the spectacle lens is determined to be 4 or more, the arithmetic control circuit 80 changes the bevel curve of the bevel curve so as to switch from the bevel processing by the normal V groove bevel grindstone of the grinding wheel 35 to the bevel processing by the small diameter bevel grindstone 200. Depending on the size, the bevel grindstone can be selectively switched by a switch or the bevel grindstone can be automatically switched.

<Groove processing>
When the eyeglass lens ML is ground to be held by the wire of the rimless frame, the peripheral surface of the eyeglass lens ML that has been ground into a target lens shape based on the processing data (θi ′, ρi ′) is next. The grooving process is performed as described above.

  That is, the arithmetic control circuit 80 controls the rotation arm drive motor 36 via the pulse motor driver 86, thereby rotating the rotation arm drive motor 36 via the worm gear 36 a and the worm 37. And the rotation arm 38 is rotated upward (to the lens shafts 23 and 24 side), and the lens shaft driving motor 25 and the pulse motor 59 are controlled to operate the lens shafts 23 and 24 and the spectacle lens ML. Lower.

  Here, the data of the initial position in the vertical direction of the rotating shaft 39 held by the rotating arm 38 and the distance between the lens shafts 23 and 24 and the rotating shaft 39 at the initial position from the initial positions of the lens shafts 23 and 24 are shown. The data is known and is attached to the rotation shaft 39 and the data of the processing radius ρ0 ′ at the rotation angle θ0 ′ of the lens shafts 23 and 24 at the initial position (i = 0) of the processing data (θi ′, ρi ′). The data of the radius or diameter of the obtained grooving cutter 40c is known.

  Therefore, the arithmetic control circuit 80 controls the operation of the rotation arm drive motor 36 based on these known data, thereby rotating the rotation arm 38 upward to raise the rotation shaft 39, while the pulse motor 59, the lens shaft holder 61 is lowered based on the above-mentioned known data, the lens shafts 23 and 24 and the spectacle lens ML are lowered, and the initial position (i = i) of the processing data (θi ′, ρi ′). 0), the groove cutter (groove grindstone) 40c is brought into contact with the peripheral surface of the spectacle lens ML at the processing initial position of the processing data (θ0 ′, ρ0 ′). The arithmetic control circuit 80 detects that the grooving cutter (grooving grindstone) 40c is in contact with the peripheral surface of the spectacle lens ML based on the detection signal from the sensor S, and operates the motors 36 and 59. Stop.

  Next, the operation control circuit 80 controls the operation of the pulse motor 59 to slightly separate the spectacle lens ML from the grooving cutter 40c, and then rotationally drives the grindstone drive motor 39a via the motor driver 86b, so that the groove The digging cutter 40c is rotated. The rotation of the grindstone drive motor 39a is transmitted to the rotation shaft 39 via a rotation transmission mechanism (not shown), and the rotation shaft 39, the chamfering grindstones 40a and 40b, and the grooving cutter 40c are rotated together.

  At the same time, the arithmetic and control circuit 80 obtains machining data (θi ′, ρi′−a) obtained by subtracting the groove depth a from the machining radius ρi at the rotation angle θi ′ of the lens shafts 23 and 24 and the minute grinding machining amount Δa ( Based on Δa << a), the motors 25 and 59 are controlled to operate until a groove having a final machining radius (ρi′−a) is formed on the peripheral surface of the spectacle lens ML. That is, the arithmetic control circuit 80 controls the operation of the lens shaft driving motor 25 based on the rotation angle θi ′, controls the rotation of the lens shafts 23 and 24 for each rotation angle θi ′, and grinds for each rotation angle θi ′. The operation of the pulse motor 59 is controlled based on the processing amount Δa, and the lens shafts 23 and 24 and the spectacle lens ML are lowered at each rotation angle θi ′, and the peripheral surface of the spectacle lens ML is circumferentially driven by the groove cutter 40c. The extending groove is ground (cut) by Δa until the groove depth becomes a.

  By such rotation of the groove cutter 40c and the raising / lowering control of the spectacle lens ML, a groove extending in the circumferential direction and having a groove depth a is formed on the peripheral surface of the spectacle lens ML.

  By the way, as described above, the arithmetic control circuit 80 controls the operation of the pulse motor 59 at the rotation angle θi ′ of the lens shaft driving motor 25 so that the grinding depth of the groove formed on the peripheral surface of the spectacle lens ML is the groove. Until the depth a is reached, the grinding depth of the groove formed on the peripheral surface of the spectacle lens ML is gradually increased based on the grinding amount Δa.

  In grinding such grooving, the arithmetic control circuit 80 controls the operation of the pulse motor 59 to drive the spectacle lens ML up and down in small increments with respect to the grooving cutter 40c according to the rotation angle θi ′. For this reason, the contact state of the spectacle lens ML with the grooving cutter 40c changes in small increments, the grinding pressure of the grooving cutter 40c with respect to the spectacle lens ML varies in small increments, and the peripheral surface of the spectacle lens ML by the grooving cutter 40c changes. Cutting amount fluctuates.

  Thus, when the grinding pressure of the grooving cutter 40c with respect to the spectacle lens ML varies in small increments, this variation is transmitted to the drive motor 39a via the grooving cutter 40c, the rotary shaft 39 and a power transmission mechanism (not shown), and this variation occurs. The grinding pressure acts as a load on the drive motor 39a to change the rotation speed of the drive motor 39a. This fluctuation in the rotational speed changes the drive current flowing through the drive motor 39a. This energization control is performed by a motor driver 86b having a current detection circuit 86b1, and the current detection circuit 86b1 detects a drive current of the drive motor 39a by the motor driver 86b. The current detection circuit 86b1 inputs the detected current value to the arithmetic control circuit 80 as a current detection signal.

  Then, the arithmetic control circuit 80 applies a large load to the drive motor 39a, which is a small drive unit, due to the above-described fluctuation of the grinding pressure (temporarily increases the grinding removal amount), and the drive motor 25 of the lens shafts 23, 24. Is stopped to prevent the drive motor 39a from being overloaded. That is, the arithmetic control circuit 80 detects that the rotational speed of the drive motor 39a has decreased to a predetermined value or less (limit value) due to the grinding pressure from the change in the detected current value from the current detection circuit 86b1. When the current value exceeds a predetermined value, it is determined that the limit value immediately before the drive motor 39a stops (a value at which the motor does not stop) is reached, the operation of the drive motors 25 and 59 is stopped, and the lens shaft 23 is stopped. , 24 and the spectacle lens ML are temporarily stopped. Then, the arithmetic control circuit 80 monitors the value of the drive current of the drive motor 39a by the current detection value, and when the current detection value becomes a predetermined value or less, the drive current of the drive motor (drive unit) 39a is sufficiently large. It is determined that the motor has been lowered, and drive control of the motors 25, 59, etc. is performed in order to perform normal grooving again.

  In this way, the arithmetic control circuit 80 makes the current detection signal (detected current value) of the drive motor (drive unit) 39a work as if it were a finishing switch. Then, the arithmetic control circuit 80 determines that the state where the detected current value, which is the current detection signal, is a normal value and the current detection signal does not fluctuate is the finished state, while the detected current value varies. The state is treated as a finished incomplete quantity state, and a stepping action is performed in the same manner as in normal machining.

  In addition, the arithmetic control circuit 80 measures the time when the current detection value varies. Then, the arithmetic control circuit 80 is a value of an excessive current flowing through the drive motor 39a when the detected current value fluctuates and the current detected value applies a load to the drive motor 39a to stop it, or approximately this value. When they are in the same range, it is determined that the drive motor 39a has been stopped due to overload for a certain period of time and an abnormal situation has occurred, and the operation of the motors 25, 39a, 59 is stopped. As a result, it is possible to avoid the danger that overcurrent continues to flow through the drive motor 39a. By controlling the drive motors 25, 39a and 59 by such a method, even if the drive motor 39a is used as a drive unit with a small rotational torque, the load fluctuations on the drive motor 39a accompanying fluctuations in the grinding pressure on the grooving cutter 40c. It is possible to complete a system (mechanism) that can cope with the above, and it can be completed as a system (device) that is energy-saving, has no waste, and is highly safe.

  Note that when the current increases, the load is determined to be large, and the lens shaft rotation is temporarily stopped. However, at present, the above control is insufficient, so the lens shaft is not only stopped but also moved away from the grindstone. Control may be performed so as to escape in the direction, the current limit is eliminated, and then approach again. In addition, even when the lens shaft is separated from the grindstone by a certain amount, when the current is limited, it may be recognized as abnormal and the processing may be interrupted. This is not limited to grooving, but also in chamfering.

  Also, chamfering is performed on the edge (side portion of the peripheral surface) of the spectacle lens ML in which a groove for holding the beveled spectacle lens ML or the wire of the rimless frame as described above is formed on the peripheral surface. Also when performing, the grinding pressure of the chamfering grindstone 40a or 40b with respect to the spectacle lens ML varies in the same manner as in the case of grooving. Therefore, in this case as well, the drive motor 39a is controlled to have a small rotational torque by detecting the drive current of the drive motor 39a and controlling the drive motors 25, 39a, 59, etc. in the same manner as the above-described grooving. As a drive unit, a system (mechanism) that can cope with load fluctuations to the drive motor 39a accompanying fluctuations in grinding pressure to the grooving cutter 40c can be completed, energy saving, wasteless and highly safe system (Device) can be completed.

  Furthermore, the grinding wheel can be tilted so as to approach or move away from the spectacle lens, and therefore, a small-diameter bevel grindstone can be applied particularly for grinding spectacle lenses of any size. .

  As described above, according to the spectacle lens grinding apparatus of the present invention, the degree of curvature in which the entire apparatus is complicated and large-sized, and the beveling of a normal lens is also a small, horizontally long and crab-shaped lens shape. The beveling of large plastic lenses can also be realized.

  As described above, the lens grinding method according to the embodiment of the present invention is the lens shape data (θi, ρi) [lens shape data], lens shape data ( The curve value of the bevel curve of the spectacle lens ML is obtained from θi, ρi), and a V-groove bevel wheel [large diameter bevel wheel (not shown in detail) provided on the grinding wheel 35] and a small diameter according to the obtained curve value. The V-groove bevel grindstone (the bevel grindstone 200) is selectively used.

  According to this method, since the curve value of the bevel curve formed after the peripheral edge processing of the spectacle lens MML is obtained, and the bevel processing is performed using the tapered small-diameter bevel grindstone based on the curve value. For example, even with beveling of the peripheral edge of the spectacle lens ML such as a sports spectacle frame having a very large degree of curvature such as a +8 curve, the grinding process can be realized efficiently.

  In the lens grinding method according to the embodiment of the present invention, the small-diameter bevel grindstone (the bevel grindstone 200) is tapered.

  Furthermore, the lens grinding apparatus according to the embodiment of the present invention provides the lens shape data (θi, ρi) [lens shape data] and the lens shape data (θi, ρi) of the spectacle frame F into which the spectacle lens ML is framed. Calculating means (arithmetic control circuit 80) for inputting the curve value of the bevel curve of the spectacle lens ML, and a V-groove bevel grindstone for beveling the peripheral edge of the ground spectacle lens ML [a large diameter bevel provided on the grinding grindstone 35]. A grindstone (not shown in detail)] and a small-diameter V-groove bevel grindstone (the bevel grindstone 200). In addition, the calculation means (calculation control circuit 80) is configured to select a V-groove bevel grindstone [a large-diameter bevel grindstone (not shown in detail) provided on the grinding wheel 35] and a small-diameter V-groove bevel according to the input curve value. The grindstone (the bevel grindstone 200) is used properly and controlled.

  According to this apparatus, the curve value of the bevel curve formed after the peripheral processing of the spectacle lens MML is obtained, and the bevel processing using the tapered small-diameter bevel grindstone is performed based on the curve value. Even in the case of beveling of the peripheral edge of the spectacle lens ML such as a sports spectacle frame having a very large degree of curvature, the grinding process can be realized efficiently.

  Further, the small-diameter V-groove bevel grindstone (the bevel grindstone 200) of the lens grinding apparatus according to the embodiment of the present invention has a tapered shape.

  In the lens grinding method according to the embodiment of the present invention, the peripheral edge of the unprocessed spectacle lens ML is ground into the target lens shape by the grinding wheel 35 based on the target lens shape data (θi, ρi) of the spectacle frame F. After that, the curve value of the bevel curve at the periphery of the spectacle lens ML after the grinding process is obtained, and a large-diameter bevel grindstone provided on the grinding grindstone 35 is provided separately and formed in a taper shape based on the curve value. The beveling process is performed on the ML peripheral edge portion of the spectacle lens formed into the target lens shape by the small-diameter bevel grindstone (the bevel grindstone 200).

  According to this method, since the curve value of the bevel curve formed after the peripheral edge processing of the spectacle lens MML is obtained, and the bevel processing is performed using the tapered small-diameter bevel grindstone based on the curve value. For example, even with beveling of the peripheral edge of the spectacle lens ML such as a sports spectacle frame having a very large degree of curvature such as a +8 curve, the grinding process can be realized efficiently.

  Further, the lens grinding apparatus according to the embodiment of the present invention is an unprocessed workpiece held between a pair of lens rotation shafts (lens shafts 23 and 24) based on the target lens shape information (θi, ρi) of the spectacle frame F. Edge thickness measurement for tracing a portion along the target lens shape information (θi, ρi) of the circular spectacle lens ML and measuring a peripheral thickness of the portion along the target lens shape information (θi, ρi) of the spectacle lens ML. Means (edge thickness measurement system 18), a grinding wheel 35 for grinding the spectacle lens ML into a target lens shape based on the target lens shape information (θi, ρi), and the spectacles ground into a target lens shape. The large-diameter bevel grindstone provided on the grinding wheel 35 for beveling the periphery of the lens ML and the large-diameter bevel grindstone are provided separately and formed in a tapered shape with a smaller diameter than the spectacle lens ML. Small diameter bevel abrasive A stone (bevel wheel 200), driving means (motor 531) for driving the small-diameter bevel wheel (bevel wheel 200) forward and backward relative to the spectacle lens ML, and the spectacle lens ML obtained from the edge thickness shape Calculation means (calculation control circuit 80) for obtaining the curve value of the bevel curve after the peripheral processing of the spectacle lens ML from the lens shape data. In addition, the calculation means (calculation control circuit 80) performs beveling on the periphery of the spectacle lens ML by the small-diameter bevel grindstone (the bevel grindstone 200) instead of the normal bevel grindstone based on the curve value. The drive means (motor 531) is controlled to operate.

  According to this configuration, the curve value of the bevel curve formed after the peripheral processing of the spectacle lens ML is obtained, and beveling using a tapered small-diameter bevel grindstone (the bevel grindstone 200) is performed based on the curve value. For example, even if the bevel processing is performed on the peripheral edge of a spectacle lens such as a sports spectacle frame having a very large degree of curvature such as a +8 curve, it is possible to efficiently achieve grinding.

  Furthermore, the lens grinding apparatus according to the embodiment of the present invention is driven forward / backward with respect to the spectacle lens ML held between the lens rotation shafts (lens shafts 23, 24) by the driving means (motor 531). It has an arm (rotating arm 500). In addition, the small-diameter bevel grindstone (the bevel grindstone 200), the chamfering grindstones 520a and 520b, and the grooving grindstone 520c are attached to the arm (rotating arm 500).

  According to this configuration, the small-diameter bevel grindstone (the bevel grindstone 200) is attached to the support shaft (rotary shaft) 518 to which the chamfering grindstones 520a and 520b and the grooving grindstone 520c are attached. The number of parts can be reduced.

It is explanatory drawing which shows the relationship between the spectacles lens grinding apparatus which concerns on this invention, and a frame shape measuring apparatus. 1 shows an eyeglass lens grinding apparatus according to the present invention, in which (A) is an enlarged explanatory view of a first operation panel, and (B) is a front view of a liquid crystal display. 1 shows a spectacle lens grinding apparatus according to the present invention, wherein (a) is a perspective view of a main processing part in a processing chamber, and (b) is a sectional view of a cover plate part of (a). FIG. 4 is a perspective view of a drive system including the configuration of FIG. 3. It is the perspective view which looked at the carriage holding the lens axis | shaft of FIG. 4, its base, etc. from back. FIG. 5 is a side view showing the machining pressure adjusting mechanism and the inter-axis distance adjusting mechanism of FIG. 4. It is the front view of the principal part which carried out the cross section which shows other embodiment of the grinding | polishing means in the spectacles lens grinding apparatus which concerns on this invention. It is a perspective view which shows the positional relationship of the grinding means in embodiment shown in FIG. It is a block diagram of the control means in the spectacle lens grinding apparatus which concerns on this invention. It is explanatory drawing which shows the relationship between a to-be-processed lens lens and a grindstone. FIG. 11 is an explanatory view showing a relationship between a lens to be processed and the grindstone showing the whole of FIG.

Explanation of symbols

F ... Eyeglass frames 23, 24 ... Lens axis (lens rotation axis)
ML ... Eyeglass lens 18 ... Edge thickness measuring system (edge thickness measuring means)
35 ... grinding wheel 200 ... bevel wheel 531 ... motor (driving means)
80. Arithmetic control circuit (calculation means)
500 ... Rotating arm (arm)
520a ... Chamfering grindstone 520b ... Chamfering grindstone 520c ... Groove grindstone

Claims (2)

A carriage that moves up and down around the carriage rotation axis at the rear, a pair of lens rotation shafts held at the front end of the carriage , and a non-rotated shaft that has a V groove bevel grindstone and is held between the pair of lens rotation shafts When processing the peripheral edge of the spectacle lens using a lens grinding apparatus comprising a grinding wheel for grinding the peripheral edge of the spectacle lens for processing and a small-diameter bevel grindstone that is advanced and retracted relative to the spectacle lens,
An operation control circuit controls an inter-axis distance adjusting means for adjusting an inter-axis distance between the lens rotation shaft and the grinding wheel based on the processing data of the spectacle lens, and the front end portion of the carriage is centered on the turning shaft. The peripheral edge of the unprocessed spectacle lens is ground into a target lens shape with the grinding wheel while adjusting the distance between the shafts ,
When the bevel curve value of the bevel formed on the peripheral edge of the spectacle lens processed into the target lens shape is smaller than 4 , the peripheral edge of the target spectacle lens is beveled with the V groove bevel grindstone. When the bevel curve value is 4 or more, a lens grinding method is performed by switching from the V-groove bevel grindstone to a small-diameter bevel grindstone and beveling the peripheral portion of the lens-shaped spectacle lens with the small-diameter bevel grindstone. In
The interaxial distance in the calculation of the moving radius ρn at the rotation angle nΔθ of the target lens shape data (ρn, nΔθ) is Ln as ρn + R, and the virtual processing point of the spectacle lens at the interaxial distance Ln is a virtual processing point. Let Fi be the actual contact position between the grinding wheel at the rotation angle nΔθ and the lens to be processed, which is the raw spectacle lens, and let ρj be the actual contact between the lens rotation axis and the grinding wheel at the actual contact position ρj. And Ln ′, the difference between the calculated inter-axis distance Ln and the actual inter-axis distance Ln ′ is an error ΔL, and the virtual machining point Fi and the virtual machining point Fi at the rotational radius ρn of the rotation angle nΔθ When the deviation angle from the contact processing point that is the actual contact position of the spectacle lens to the grinding wheel is dθn,
The arithmetic control circuit calculates the inter-axis distance Ln from the target lens shape data (ρn, nΔθ) [n = 0, 1, 2, 3,... J] and the radius R of the grinding wheel. Machining information (Ln, ρn, nΔθ) is determined from the inter-axis distance Ln and the target lens shape data (ρn, nΔθ), and the target lens shape data (Ln, ρn, nΔθ) is determined when determining the processing information (Ln, ρn, nΔθ). The deviation angle dθn is obtained based on ρn, nΔθ) and the radius R of the grinding wheel, and new machining information (Ln, dθn, ρn, rho) is obtained from the obtained deviation angle dθn and the machining information (Ln, ρn, nΔθ). On the other hand, after obtaining the actual inter-axis distance at the contact position ρj with Ln ′ being Ln + ΔL, switching from the V-groove bevel wheel to a small-diameter bevel wheel is replaced with the magnitude of the bevel curve value. Based on the deviation angle dθn, the inter-axis distance adjusting means is constructed. Lens grinding method characterized by performing beveling the peripheral edge of the eyeglass lens in the rim shape by the grindstone of the small diameter by controlling. Grinding the carriage that moves up and down around the rear carriage pivot, the pair of lens rotation shafts held at the front end of the carriage, and the peripheral edge of the raw spectacle lens held between the pair of lens rotation shafts A grindstone having a radius R to be processed, a V-groove bevel grindstone provided on the grinding grindstone, and a spectacle lens held between the lens rotation shafts are driven back and forth to bevel the peripheral edge of the spectacle lens. Adjust the distance between the grinding wheel and the lens rotation axis by moving the lens rotation shaft and the spectacle lens up and down by moving the small diameter bevel wheel and the front end of the carriage up and down around the pivot axis. An inter-axis distance adjusting means, and processing data of the spectacle lens corresponding to the lens shape data (θn, ρn) of the spectacle lens, and the inter-axis distance based on the processing data The Rukoto a release adjusting means actuating the control to rotate the front end portion of the carriage about said pivot axis, while adjusting the center distance between the grinding wheel and the lens rotating shaft, the raw glasses An arithmetic control circuit for grinding the periphery of the lens into a target shape with the grinding wheel,
When the curve value of the bevel curve of the bevel formed at the periphery of the spectacle lens processed into the target lens shape is smaller than 4 , the arithmetic control circuit uses the V-groove bevel grindstone to generate the peripheral edge of the target lens lens. When the bevel curve value is 4 or more, the bevel curve value is 4 or more, and the V-groove bevel grindstone is switched to the small-diameter bevel grindstone and the small-diameter bevel grindstone is used to bevel the peripheral portion of the lens-shaped spectacle lens. A lens grinding device for performing beveling ,
The interaxial distance in the calculation of the moving radius ρn at the rotation angle nΔθ of the target lens shape data (ρn, nΔθ) is Ln as ρn + R, and the virtual processing point of the spectacle lens at the interaxial distance Ln is a virtual processing point. Fi, and ρj is an actual contact position between the grinding wheel at the rotation angle nΔθ and the processed lens which is the raw spectacle lens,
The actual distance between the lens rotation axis and the grinding wheel at the actual contact position ρj is Ln ′, and the difference between the calculated distance Ln and the actual distance Ln ′ is an error ΔL. When the deviation angle between the virtual processing point Fi at the radius ρn of the rotation angle nΔθ and the contact processing point that is the actual contact position of the spectacle lens with the grinding wheel is dθn,
The arithmetic control circuit calculates the inter-axis distance Ln from the target lens shape data (ρn, nΔθ) [n = 0, 1, 2, 3,... J] and the radius R of the grinding wheel. Machining information (Ln, ρn, nΔθ) is determined from the inter-axis distance Ln and the target lens shape data (ρn, nΔθ), and the target lens shape data (Ln, ρn, nΔθ) is determined when determining the processing information (Ln, ρn, nΔθ). The deviation angle dθn is obtained based on ρn, nΔθ) and the radius R of the grinding wheel, and new machining information (Ln, dθn, ρn, ρn,) is obtained from the obtained deviation angle dθn and the machining information (Ln, ρn, nΔθ). On the other hand, after obtaining the actual inter-axis distance at the contact position ρj with Ln ′ being Ln + ΔL, switching from the V-groove bevel wheel to a small-diameter bevel wheel is replaced with the magnitude of the bevel curve value. Based on the deviation angle dθn, the inter-axis distance adjusting means is constructed. Lens grinding apparatus characterized by performing a beveling on the periphery of the spectacle lens in the rim shape by the grindstone of the small diameter by controlling.

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