FR2602880A1 - SYSTEM AND METHOD FOR MANUFACTURING MODEL GLASSES OF GLASSES - Google Patents

Abstract

THE PRESENT INVENTION RELATES TO A SYSTEM 10 FOR PRODUCING A MODEL OF GLASS TO BE FORMED AND THEN PLACED IN AN OPENING OF A GLASS FRAME, INCLUDING MEANS FOR PRODUCING A SET OF COORDINATE DATA CHARACTERIZING THE DIMENSION AND SHAPE OF AN OPENING OF GLASSES FRAMES; AT LEAST ONE BLANK 98 FROM WHICH A MODEL IS CUT; MEANS 14 FOR CUTTING THE Rough; MEANS 16 FOR COUPLING THE MEANS OF GENERATING DATA COORDINATES 12 WITH THE CUTTING MEANS 14; MEANS 126 ASSOCIATED WITH CUTTING MEANS 14 FOR RECEIVING THE SET OF COORDINATED DATA; AND MEANS 126, 146, 150 FOR CONTROLLING THE CUTTING MEANS 14 FOR CUTTING THE RIGGING AS A FUNCTION OF THE CHARACTERISTIC DATA TO PRODUCE A MODEL HAVING THE DIMENSION AND SHAPE OF THE OPENING OF THE GLASS FRAME.

Description

1601lsO

  SYSTEM AND METHOD FOR MANUFACTURING MODEL GLASSES OF GLASSES

  The present invention relates generally to models of spectacle lenses and more specifically relates to a system and method particularly suitable for forming a model for spectacle lenses to be manufactured and then placed in the opening of a spectacle frame in which data characterizing the size and shape of the opening of the associated lens are supplied to a model generator by a

  frame tracking coupled to the model generator.

  Heretofore, the fitting of an optical lens into a spectacle frame opening has generally relied on the manufacturer of the particular lens frame to provide a nominal size model for the opening. Such a model substantially reproduces the shape of the opening of the glass in an associated glass frame and this model is typically used as a guide for controlling a cutting device which cuts on

  its periphery a blank of optical glass according to the shape of the opening of the frame. Models supplied by a manufacturer are usually identified and often kept in an inventory maintained by the user of these models.

  In recent years, the proliferation of spectacle frame styles and the increase in the number of spectacle frame manufacturers has made it impractical for those working with an inventory of models to order and keep a model for each of the different styles. spectacle frame 25 due in particular to the increased space requirements

  necessary to store the increasing number of different models.

  In addition, the process of choosing a given model from the inventory has become very difficult, inconvenient and time consuming, particularly in a large laboratory where a given model 30 may be in use and not available for purchase. selection.

  In smaller laboratories, it may not be economical or reasonable to maintain an inventory of models.

  In many cases, a model is made either directly or indirectly from a frame and from a trace of the opening of the lens in the frame. One such method of making a model uses a model blank which includes a grid scale consisting of distances measured to the left, right, top and bottom from an origin printed on the blank. The origin of the grid coincides with the mechanical center of a blank and therefore the mechanical center of a model made from a blank. When using such a blank, the mechanical center of the glass aperture and the mechanical center of the blank must be properly aligned because a very small error, as small as a few 15 tenths of a millimeter can cause improper mounting of the glass. In addition, the horizontal axis of the lens opening in the frame and the horizontal axis of the model must be kept parallel to each other to ensure that the optical system of a lens made from a corresponding model is conveniently placed in front of the eye when the glass is in

  the opening of the spectacle frame.

  Once the opening of the spectacle frame is properly aligned horizontally and centered, the shape of the opening of the glass is transferred to the grid on the blank by tracing the opening of the glass with a tracer pencil or other device. appropriate marking and the blank of the model is cut according to the marked contour to produce the model. Any roughness in the edge of the model is usually smoothed with a file

or with a wheel wheel.

  There is no guarantee that a model manufactured using the above process will have the same size and shape as the rewind opening of the frame unless compensation is made for the thickness of the line of the tracing pencil and the depth of the groove. of the mount, 35 among other things. In addition, there may be variations from one lens frame of the same style to another, in which case a pattern produced for one frame lens opening may not be suitable for another frame lens opening from the same style

glasses frame.

  The above process of tracing an aperture of 5 frame glasses and producing the associated model requires great skill, takes time, often up to five minutes, to trace and form a model, and submits an optical lens. made from an incorrectly centered model and dimensioned for improper mounting in the opening of the frame and causes an optical error. In addition, the above method is not suitable for economical manufacturing of large quantities of identical models.

or different.

  It is therefore a general object of the present invention to provide a system for producing models from a blank according to which the manufactured model reproduces the

  dimension and shape of a glass opening in a spectacle frame and, another object is to provide that the data characterizing the dimensions and shape of the glass opening be transmitted directly to a model generator from 20 d '' a frame tracking device.

  Another object of the invention is to provide such a system consisting of individual system components which can be interconnected to be used very close to each other at a first location or alternatively on a circuit between a frame-drawing apparatus and a generator or device for producing

  models located far from each other in different locations.

  Another object of the present invention is to provide such a system for producing a large quantity of models of

  different forms in a relatively short time.

  These general objects are achieved according to the invention, and as described in more detail below, by a system for manufacturing a model of lens comprising an apparatus for tracing spectacle frame glasses to characterize the dimension and the shape d a glass opening in an associated spectacle frame 35 and means for transmitting data to a model generator which may be located near or far from the plotting apparatus, this generator cutting out a model

  corresponding from a blank supplied to the generator.

  Other objects and advantages of the present invention will appear on reading the following description of a mode of

  preferred realization in relation to the drawings. The present invention relates to a system and associated method for producing a model of a lens to be produced and then placed in the opening of a spectacle frame in which data characterizing the size and shape of the associated opening glass is supplied to a model generator by a frame-drawing device coupled to the model generator, in which the generator cuts a corresponding model

  from a blank supplied to the generator.

  The frame tracking apparatus includes a stylus mount for following the lens edge groove along the inner periphery of a lens opening and multiple data points along the path of the stylus path are detected and coded . A controller in the plotter calculates the coordinates of each of the detected data points and uses the block measurement system to provide dimension data in the form of lengths along axes A 'and B, the effective diameter and the length of each ray and its angle associated with predetermined spacing positions along the periphery of the opening of the glass. The dimension data is transmitted to a model generator directly or through a central database computer coupled to

the frame tracking device.

  The model generator comprises a knife which moves in a rectilinear path and with respect to the rotational movement of a blank fixed to a related work station.

  with control signals produced by a control device. The controller includes an instruction set which receives the dimension data and calculates the relative displacement between the knife and the rotation of the blank to provide a model having the desired size and shape.

  The system also includes chain assembled blanks intended to be supplied to the model generator, each blank being arranged to be interconnected and folded in like faces with the next to form a compactly folded stack. Each blank also includes marks 5 to identify the side of the nose or nasal of a model cutout.

from the draft.

  In the drawings: Figure 1 is a schematic perspective view showing a system embodying the present invention for manufacturing a model of a glass opening in a spectacle frame in which the main components of the system are

arranged in a single location.

  FIG. 2 schematically represents several dimensional parameters associated with the block measurement system; Figure 3 is a schematic top view of the tracing apparatus used with the system of Figure 1, the cover being removed and showing the arrangement of the encoder arms and their respective connection to the stylus assembly; FIG. 4 is a top view of several blanks in a chain particularly suitable for automatic feeding of the model generation apparatus; Figure 5 is a side view of several blanks in a compactly folded chain; Figure 6 is a schematic front view of the model generation apparatus used with the system of Figure 1 with the cover removed; and FIG. 7 is a diagram in the form of functional blocks of the system implementing the present invention in which several frame tracking devices are coupled to a model generation device arranged remotely, via a computer. central data base arranged for communication with the frame-tracing apparatus by

a data link system.

  Referring to the figures and more particularly to Figure 1, a system embodying the present invention for forming a model of a glass opening in a spectacle frame is shown and generally designated by the reference 10. The system 10 comprises a frame tracking device 12 and a model generation device 14 coupled to the frame tracking device by a multi-wire electrical conductor 16, this conductor carrying the electrical signals between the frame tracking device and the model generation apparatus in a direction illustrated figuratively by the arrow 18. The tracing apparatus 12 comprises a housing 20 comprising a support part 22 and a cover 24. The housing 20 10 also comprises a substantially flat surface 26 along which a stylus mount 28 is moved in a plane substantially parallel to the plane of the surface 26. In the embodiment shown, the tracking apparatus e 12 is shown as it is used to trace a glass opening in a spectacle frame. However, it should be noted that an optical lens or a model can be traced to provide the characteristic data intended to be used by the generation apparatus of

models 14.

  The cover 24 includes a keypad 30 for entering data, instructions or other information in the form of digitally coded electrical signals coupled to electronic components on an electronic circuit board 32, these components comprising control, calculation , and other circuits of the tracing device. The circuit board 32 is coupled to various sub-assemblies constituting the plotting apparatus and to the keyboard 30 via an electrical conductor to

multiple links 34.

  A control device or microprocessor 36 is disposed on the circuit board 32 and includes a memory for containing a set of instructions constituting a control program. The program causes the control device, in response to the various electrical signals introduced and detected, to control, according to the set of instructions, the operation of

the tracing device 12.

  An option selection switch 38 is disposed on the circuit board 32 and is electrically coupled to the controller 36. The switch 38 is an eight bit two-row parallel aligned pin (DIP) switch and is operated according to one desired from multiple positions. Each different position produces a different digital signal coded in binary to select a display on an alphanumeric display device 50 or a print on a printer 49, of a corresponding one of several predetermined combinations of output information associated with the characterization. the size and shape of a traced glass opening, a traced glass, or a traced pattern. The characterization of the

  dimension and shape of a frame lens opening, lens, or model is shown dimensionally using the block measurement system.

  FIG. 2 is a diagram illustrating the representation of several dimensional parameters associated with the block measurement system. The center of a block is defined as the center of the smallest rectangle which is circumscribed to a form of glass 40 using horizontal lines 42, 42 and vertical lines 44, 44. The dimension of the model or dimension A is defined as the distance between the two vertical sides 44, 44 of the block. Dimension B is defined as the distance between the horizontal lines 42, 42. The center of the block corresponds to the mechanical center of the block and therefore to the glass or the model in cases where off-center is not required. Once the dimensions of the block and the mechanical center have been determined, the longest diameter or effective diameter (ED) passing through the center of the block can be determined. The effective diameter (ED) is used to select a minimum glass blank size to ensure that a desired shape can be cut from this blank, i.e. a glass will not be ground thicker than necessary no more

  thin at its edges for a specific frame chosen.

  Returning to FIG. 1, and considering the options which can be chosen by actuation of the switch 38, each option brings ray lengths at several predetermined separate locations along the traced path and other dimensional data such as only the dimensions A and B and the ED value to be displayed or printed. For example, a selected option causes the instruction set to display ray lengths at 90 degree intervals and another selected option causes the instruction set to display 5 ray lengths at 45 degree intervals along the chosen route. Combinations which differ from predetermined combinations can be implemented by modifying the instruction set. Only a predetermined number of radius values of the total number of radius values calculated by the set of instructions is displayed according to a given chosen option. The set of instructions in the preferred embodiment actually characterizes a given trace by calculating 400

  radius values and their respective associated angles.

  The alphanumeric display device 50 is mounted on the cover 24 and is electrically coupled and controlled by

  the electronic circuit disposed on the circuit board 32.

  The display 50 acts as an operator support by displaying messages and instructions for implementing the tracing procedure and also displays the status of the tracing apparatus 20 during the tracing sequence. The display 50 further displays, as mentioned above, the value of the dimension data associated with characterizing the size and shape of a traced glass opening, traced glass or a traced model. Display mode is activated to sequentially display the dimension data after a trace has been completed by pressing the display function key

(DISPLAY) 52 on the keyboard 30.

  The printer 49 is connected to the plotting apparatus 12 via a multi-wire conductor 47 and is electrically controlled by electronic circuits arranged on the circuit board 32. The printer 49 is actuated by acting on the print function key (PRINT) 51 on the

keyboard 30.

  A glass support bridge designated by the reference 54 35 is used to support the spectacle frame, shown in dotted lines in FIG. 1 and designated by the reference 56, so that the opening of the tracing glass is maintained on the surface on which the stylus mount 28 moves. The bridge 54 is arranged for a limited pivoting movement about an axis 58 to allow adjustment of the plane of a glass opening in a frame 56 supported by the bridge 54 so that 'he be

  substantially parallel to surface 26.

  A spectacle frame support mechanism 60 is mounted on a platform 62 disposed in the vicinity of the bridge 54 and is adapted to move in the direction of an arrow 64. The spectacle frame support mechanism 60 comprises a

  self-locking frame mounting 66 which slides coaxially along the surface of a rod 68 comprising the support mechanism 60. The frame is placed on the bridge 54 and oriented above the surface 26 so that this frame is placed against a front edge surface 70 of the deck 54 and 72 of the platform 62.

  The edge surfaces 70 and 72 are substantially in alignment so that, when a frame is placed in contact with the edge surfaces, the axis A of the spectacle frame is suitably oriented relative to the axis A of a lens or of a model 20 associated with the opening of the lens in the frame. After proper positioning of the frame, the element 66 is made to slide in contact with the spectacle frame using the pressure of the thumb and locks in contact with the frame to maintain it

  against the front edge surface 70 without distorting the frame.

  Referring again to Figure 1 and further to Figure 3, the stylus mount 28 is shown as rotatably coupled about a longitudinal axis 74 before two encoder arms 76 and 78, respectively. The encoder arm 76 has a variable length and includes an axially elongated rod whose free end 80 is supported by a rotary coding mechanism 82. The arm 76 is arranged to move back and forth in a direction indicated by the arrow 84 while the length of the arm changes when the stylus mount 28 is moved along the surface to be traversed 26. The encoder arm 78 is substantially identical to the encoder arm 76 35 and has a variable length and comprises an axially elongated rod whose l free end 86 is supported by a

- rotary coding mechanism 88.

  The rotary coding mechanisms 82 and 88 are mounted spaced apart from each other and at a predetermined distance and form one side of a triangle. The data representing and corresponding to the distance C is used by the set of instructions in the control device 36 in relation to the data representative of the changes in length of the encoder arms 76 and 78 as detected by the coding mechanisms 82 and 88. The lengths of the coding arms 76 10 and 78 are represented by the distances A and B, respectively, and each form a side of the triangle defined by the sides A, B and C. The rotary coding mechanisms 82 and 88 are electrically coupled to an electronic circuit disposed on the circuit board 32, this circuit detecting the electrical signals produced by the coding mechanisms while the lengths of the coding arms 76, 78 change as the stylus mount 28 is moved along the way to go. Since the change in lengths A and B from an initial calibration position 20 is known at each of the positions detected along the course path and the length C is predetermined and known, the coordinates associated with each data point detected can be determined using well known trigonometric rules. Referring again to Figure 1, a work function key (JOB) 90 located on the keyboard 30 is used to assign an identification number to a set of dimensional data for a given plot to then allow access to this data and retrieve it from a memory 30 in the tracing device or in a computer with a database

as will be described below.

  The plotting apparatus 12 includes circuits for converting the dimension data of a plotting into digital code words for transmission to the model generation apparatus 14 or to a database computer as will be described in connection with Figure 7 using well known data transmission techniques. In one embodiment, the tracing apparatus 12 includes circuits located on the circuit board 32 to convert the digitally encoded words into a well known RS-232 data format and to provide the necessary transmission supervision signals and reception control. Data transmission is ensured by the operation of a transmission key (TRANSMIT) 92 which causes the associated circuit to send the appropriate supervision signals and the data to the model generation apparatus 14 on the conductor 10 16 connecting the plotting device and the model generation device. The model making apparatus 14 includes a blank supply and routing area generally designated by the reference 92 through which a blank passes in the direction shown by the arrow 94 along a certain path in the generator. The blanks can be supplied one by one, but are preferably supplied along a chain 96 which is shown in FIGS. 4 and 5. FIG. 4 represents several blanks 98 placed end to end such that they can be supplied along the 'supply and routing stage 12 of the model generator. FIG. 5 represents several blanks 98 placed face to face to form a compactly folded assembly. Each blank 98 comprises a relatively thin body of rectangular shape having an upper surface 100 and a lower surface 102, the blanks being arranged to be connected by edge-to-edge hinges. The lower surface 102 of each blank 98 comprises teeth 104 constituting a rack along each edge 106, 108 of the blank. The model generator 14 includes a hinged cover 110 in the blank supply and routing region 92 and the cover opens in a direction indicated by an arrow 112 by pivoting about an axis 114 when fasteners 116 are actuated to release the cover. A button 118 protrudes from an outer front wall 120 of the blank supply and delivery stage and is coupled to drive gears with teeth in engagement with the teeth 104 along the edges 106 , 108 of a draft. The rotation of the button causes the drive teeth to rotate to facilitate the loading of a blank 98 into a chain 96 of blanks inside the generator. The model generator 14 also includes a keyboard 122 for selecting various functions of the model generator and for sending information to the generator. A display 124 is used as assistance to an operator and 10 displays messages and instructions as well as other information and data. A microprocessor or control device 126 is contained on a circuit board 128 at the same time as other electrical components constituting the electronic circuit necessary to control the operation of the generator of models 14. The control device 126 comprises a memory

  to contain a set of instructions and works in conjunction with the set of instructions to control cutting and other operations performed by the model generator.

  A hinged access panel 130 opens in the direction of arrow 132 around a pivot axis 134 to allow access to components in the workstation region located in the area below of the panel. A model 136 cut at the work station is discharged from one side 138 of the generator in the direction of arrow 140 and cutting waste 142 which appears as a result of cutting the model from a blank is provided from the

  generator in the direction of arrow 144.

  Figure 6 shows a schematic front view of the model producing apparatus 14 used with the system 30 embodying the present invention, the cover being removed. The generator 14 includes a drive mechanism generally designated by the reference 146 for moving these blanks along a path 148 to a machining station generally designated by the reference 150. The drive mechanism 146 comprises an assembly pinions 152 and 154 arranged opposite each other on the two sides of the path 148 and spaced apart from each other so that the teeth of the drive pinions 152, 154 have a constant pitch for teeth appearing on. the lower surface of the blanks 98 provided along the path 148. A stepper motor 156 includes a drive pulley 158- coupled to the drive sprockets 152, 154 by a drive belt 160 to rotate the sprockets

synchronously.

  A detector 162 is located along an edge of the path 148 and cooperates with a light-emitting diode (LED) 164 mounted in the cover 110. The LED 164 is aligned opposite the detector 162 when the cover is in its closed position. so that a blank 98 moving along the path 148 passes through an energy beam established between the detector 162 and the LED 164. The detector 162 and the LED 164 are located at a predetermined distance from the machining station 150 for allow precise location of a blank along the path 148 by the pinions 152, 154 while the stepper motor 156 operates according to the control signals from the control device 126. When the energy beam between the detector 162 and LED 164 is interrupted by the presence of an edge of a blank 98 which advances along the path 148, the interruption of the beam is detected by the control device 126 and a counter positioned in the control device to bring the moteu r step by step 156 to rotate the drive pinions 152, 154 for a specific number of 25 steps to advance the blank by a predetermined distance on

along the way.

  In addition to detecting the edge of a blank, the presence of the energy beam passing through the opening 166 in the body of the blank is detected by the controller 126 30 to determine the orientation of the nasal side d a blank at the machining station 150. Determining the orientation of the nasal side of a blank at the machining station is necessary to transform the data characterizing the size and shape of a model to be cut from the blank so that the data corresponding to the nasal side is correlated with the nasal side of a model cut from the blank. As shown in FIG. 4, each blank 98 contains an opening 166 located on one side of the blank and the location of the opening corresponds to the nasal side of the blank as indicated by the letter N. The letter N is engraved on the blank and allows an identification of the nasal side of a model. Since the number of blanks between the machining station 150 and the detector 162 is known, the control device 126 responds to the presence of the energy beam passing through the opening 166 in the body of a blank at a instant predeter 10 min after the edge of the blank has been detected to determine the orientation of a blank at the machining station. Since the blanks are provided in an alternate nasal side arrangement, the instruction set in the controller 126 anticipates the detection of the presence of the energy beam for each other blank passing through the detector. If the sequence is not followed, the instruction set causes a message to be displayed to alert an operator of the fact that the sequence does not

not suitable.

  The machining station 150 comprises a fixing mechanism 167 and a blank separation mechanism, generally designated by the reference 168, for separating a blank 98 from a blank which is connected to it immediately adjacent by forcing the blanks to move apart at the hinged connection point between the blanks. The blank separation mechanism 168 comprises a separation plate 170 pivotally mounted at one end 172 on a hinge 174 comprising a hinge part 176 mounted on the surface 178 of a frame 180 on the side of the machining station 150 closest to the unloading side 138 of the model generator. The opposite end 182 of the plate 170 is connected to a push bar 184 which is itself connected to a stepping motor 186 by a threaded shaft 188 fixed to the tack bar 184 and by means of a nut 190 held and internally rotated in the stepper motor 186. The nut 190 is rotated by the stepper motor 186 to move the plate to the stepper motor 186 and thereby spreading therefrom in a direction indicated by an arrow 192. The plate 170 further includes a cup 194 attached to the bottom surface 196 of the plate so that the cup is aligned with a central mounting rod 198 associated with the fixing mechanism 166. When the stepping motor 186 is actuated in a direction suitable for separating adjacent blanks, the counter-bowl 194 engages with a central drill hole in a blank at the level of the station. machining 150 and pushes the blank onto the central mounting rod 198, f thus orcing the rod 198 into a cavity 200 of a spindle body 202 10 constituting the fixing mechanism 167. Other drill holes in the blank are aligned with locating lugs 204 and enter into engagement with the lugs while that the blank is separated from the chain of blanks. Furthermore, the blank is pushed from an input feed level to a lower machining level so that a blank fixed to the spindle body 202 can be rotated without interfering with d 'other

  chain blanks at the input feed.

  After cutting a model from a blank at the machining station 150, the stepping motor 186 is actuated to raise the plate 170 to release a model cut from a blank and to keep underway the spindle body 202. The mounting centering lug 198 is pushed upwards outside the cavity 200 by a spring 206 which forces the model to disengage from the locating lugs 204. The next draft advancing towards the 25 machining station 150 comes into contact with a model resting on the spindle body 202 and pushes the model to discharge it from the generator. The stepper motor 186 is mounted on a motor support 208 which is pivotally connected to one end 210 on the surface 212 of the frame 180 to allow the stepper motor to

  rotate and maintain alignment with the threaded shaft 188 and the push bar 184 as the distance between the stepper motor and the first end 182 of the partition plate 170 increases and decreases as the end 182 is moved in 35 a direction indicated by an arrow 192.

  The fixing mechanism 167 comprising the body of

  spindle 202 is mounted to rotate at the machining station 150 in bearings 214 and 216 and comprises a drive pulley 222 axially connected to the spindle body. A stepper motor 218 includes a drive pulley 220 coupled to the drive pulley 222 by a drive belt 224 to rotate the spindle body 202 about its longitudinal axis 226.

  The stepper motor 218 is coupled to the controller 126 and is turned on and off based on signals from the controller to rotate the spindle body 202 and thus a blank attached to the spindle body. The stepping motor 218 rotates the spindle body 202 around its longitudinal axis 226 with a resolution of 8000 steps by 360 degrees,

  that is to say, per revolution of the spindle.

  A cutting mechanism, designated by the reference 228 15 moves relative to the rotation of a blank fixed to the machining station 150 and in a direction substantially perpendicular to the path 148. The cutting mechanism 228 comprises a displacement means 230 mounted on a carriage 232 to move with the carriage back and forth relative to the machining station. The carriage 20 232 moves on guide bars 234 and 236 arranged opposite and substantially parallel to one another. The guide bars 234 and 236 are mounted on the frame 180 by mounting collars 238 and 240, respectively, at one end of the guide bars, and by other collars not shown at the opposite end of each of the bars. guide. The carriage 232 is driven along a rectilinear path back and forth relative to the machining station 150 by a stepping motor 242 comprising a threaded shaft 244 coupled to a ball assembly and

  nut 246 mounted on the carriage 232.

  The displacement means 230 comprises a body of means

  displacement 248, a displacement means spindle 250 extending lengthwise through the body 248 such that an axis 252 extending lengthwise through the center of the displacement means spindle is substantially perpendicular to the plane of the path 148 in which the blanks move.

  The spindle of the displacement means 250 is provided with a blade clamping plate 254 at one end close to the machining station 150 and a drive pulley 256 at its opposite end. A motor 258 includes a motor shaft 260 and a pulley attached thereto for rotation with the shaft and is coupled to the drive pulley 256 by a drive belt 262 to provide rotational drive of the movement means for rotating a blade of the movement means held by the

blade clamping plate 254.

  The model generator 14 cuts a model according to the data characterizing the dimension and the shape of a lens opening in a spectacle frame and this data is supplied from the frame tracking apparatus 12 as has been explained above. The set of instructions in the control device 126 transforms the 400 points characterizing the dimension 15 and the shape of the glass opening into 8000 points along the periphery defining the edge of the model. A linear interpolation algorithm in the instruction set is used to smooth the resolution differences between the 400 points provided by the frame-tracking apparatus and the 8000 points produced by the model generator. The cutting algorithm in the instruction set is similar to that used in a computer-controlled grinding machine to produce parts

  with smooth cutting edges.

  A model is cut from a blank at level 25 of the machining station after the START key 264 has been pressed, which causes the model generator to wait for data from the frame tracking device 12 when the model generator works in a local mode as it is

  chosen by the MODE 266 function key.

  FIG. 7 represents a functional block diagram of the

  system embodying the present invention in which a plurality of frame tracking apparatuses 12 are coupled to a remote model generation apparatus via a central database computer 268 arranged to communicate with the tracking apparatus mount through a data link.

  In some cases, the practitioner may have several locations at which the spectacle frames are selected and mounted for a spectacle client, for example locations constituted by a chain of optical centers among which each of the locations sends its respective orders to a central laboratory for processing, after which the work carried out is returned to the location from which the order originated. The speed of such an operation is considerably increased by using the system according to the present invention in which a glass opening in a desired spectacle frame 10 is traced at the location where the spectacle frame is suitable for a spectacle client. The data characterizing the size and shape of the opening of the glasses and an associated task number are transmitted to the database computer 268 at the central laboratory level by a conventional terminal using standard telephone lines. Once the plotting is completed by the mount plotter, the transmit function key (TRANSMIT) 92 is pressed to cause the mount plotter to activate the terminal 270 coupled to an output data access of the mount plotter by a data cable 272. Pressing the TRANSMIT 20 button 92 signals to the terminal that the characteristic data and their

  associated task identification number, which are in the form of digitally coded words, are ready for transmission by the terminal 270. The terminal 270 can be of the automatic numbering type which forms a telephone number associated with a compatible terminal, 25 by example a terminal 274 located in the central laboratory.

  The actuation of a terminal is well known to those skilled in the art and it is sufficient for the purpose of the present description that the terminal be actuable at any desired transmission rate as it is limited by the system of communication on which the terminal operates.

  The database computer 268 at the central laboratory level is coupled to the terminal 274 by a data cable 276 to receive the digitally encoded words representative of the characteristic data and the associated task identification number. The received digital information is stored in a memory in the database computer 268 along with other information received from the frame trackers at other locations. Such another location is for example represented by the terminal 278 coupled to the frame plotter 12 by the data cable 280. The terminal 278 transmits code words 5 numerically representative of the characteristic data and of an associated identification task number, via a data link, to terminal 282 located at the central laboratory. The terminal 282 is connected to the database computer 268 via a data cable 284 10 to transmit the digitally coded words to the memory of

computer 268.

  A printer 290 is coupled to the database computer 268 by a cable 292 and provides a means for listing or displaying all the job identification numbers having associated characteristic data stored in the memory, if

  such tasks are present. An operator can access all the tasks in the database computer memory by entering a desired task number in the model generator 14 via the keyboard 122 when the generator 20 is in the remote operating mode. .

  To use the model generator 14 in the remote operating mode, the MODE function key 266 on the keyboard 122 is pressed. In the remote operating mode, the controller 126 in the model generator 14 requests information from the memory of the database computer 268 through the electrical signals transmitted between the computer to database and the model generator via a data cable 286 coupling an output port of the computer to a data input port associated with the model generator. After the required information has been transferred to the template generator 14 from the database computer 268, the START function key 264 on the keyboard 122 of the template generator is pressed to cause the template generator to cut out. a model 35 according to the characteristic data required via the task identification number and received from a remote location via the central computer to

database.

  Since the operation of the model generation apparatus 14 is substantially automatic, the model generation apparatus 5 can process data transmitted to the database computer from several remote locations. In some cases, there may be distant locations of frame tracer capable of being processed by a single model generator. Consequently, two or more model generators can be coupled to the database computer, each model generator being able, by entering a task identification number, to access the memory of the database computer containing data associated with the task and characterizing the shape of a glass opening which has been introduced from a frame-tracing apparatus at a remote location. A system and associated method for producing a model for a lens to be manufactured and then placed in an opening of a spectacle frame, in which data characterizing the size and shape of the associated opening

  are provided to a model generator by the frame-tracing apparatus coupled to the model generator, have been described above in relation to particular embodiments.

  A particular type of non-limiting blank capable of being used with the model generator 14 is described in the French patent application entitled "Draft usable in an apparatus for producing models of lenses" filed the same

  updated by the Applicant and claiming priority US 06/896615.

  By way of nonlimiting example, each blank may comprise a relatively thin rectangular body provided with main faces 100 and 100 generally generally parallel, with first and second lateral edges parallel to each other and opposite, and first and second end edges,

  parallel and opposite to each other and perpendicular to said side edges.

  A series of teeth 104 disposed along the first 106 and second 108 lateral edges is capable of entering into engagement with the conveying means for moving the blank in a direction parallel to these lateral edges, and means for locating the side. nasal 166 define an opening extending through the body between said upper and lower faces and substantially in the vicinity of a first corner of the body at a predetermined distance from the first and second end edges and from the first and second side edges for 10 allow a beam of energy produced by a light emitting source in the detection means 164 to pass through the opening to be detected by a photodetector 162 in the detection means when said opening and said energy beam are in sight opposite. First hinged means 15 are disposed adjacent to the first end edge and second hinged means are disposed adjacent to the second end edge. The hinged means are located near the first and second end edges and are adapted to a valve engagement with said hinged means located near the first and second end edges of a similar blank. The hinge means are located near the first end edge of a first blank cooperating with the hinge means disposed near the first end edge of a similar front blank located adjacent to the first end edge for allowing this blank and the similar front blank to rotate relative to each other about a pivot axis of the hinged means associated with the first end edge. The second hinge means are disposed near the second end edge of the first blank cooperating with the hinge means disposed adjacent to the second end edge of a similar rear blank disposed near the second end edge to allow to this blank and to the rear similar blank to rotate with respect to one another about an axis of pivoting of the hinged means associated with the second end edge. The pivot axis of the hinge means associated with the first end edge is coplanar with one of the upper and lower faces and the pivot axis of the hinge means associated with the second end edge is coplanar

  with the other of the upper and lower faces.

  A particular non-limiting type of model generator 14 is described in the French patent application entitled "Method and apparatus for producing a model for opening a lens in a spectacle frame" filed by the same Applicant on the same day and claiming priority us

06/896 615.

  This detailed description of embodiments should not be understood as limiting.

Claims (15)

  1. -System (10) for producing a model of glass to be formed and then placed in an opening of a spectacle frame, characterized by: means (12) for producing a set of data 5 of coordinates characterizing the dimension and the shape of a spectacle opening in an associated spectacle frame; at least one blank (98) from which a model is cut; means (14) for cutting the blank; Means (16) for coupling the data coordinate generating means (12) to the cutting means (14); means (126) associated with the cutting means (14) for receiving the set of coordinate data; and means (126, 146, 150) for controlling the cutting means (14) for cutting the blank according to the characteristic data to produce a model having the size and shape of the spectacle opening associated with the frame glasses. 2. System for producing a model as claimed in claim 1, characterized in that the means for generating data coordinates (12) comprise: means (54, 60) for supporting an opening of spectacle frame glass in a plane substantially parallel to a reference plane (26), this reference plane comprising several data points comprising a data space; a tracing stylus (28) movable in the vicinity of the frame support means (54, 60) and parallel to the reference plane to follow the internal periphery of a glass opening in a spectacle frame located on the support means (54, 60), said stylet (28) being arranged to engage in complementary fashion with the glass mounting groove along the inner periphery of the glass opening of a spectacle frame; detecting means (76, 78, 82, 88) coupled to the plotting pen (20) for detecting the plotting pen at multiple data points in the data space along a path of the plotting pen ; and calculating means (32) acting in response to the detecting means (76, 78, 82, 88) for calculating the set of coordinates associated with said number of data points detected according to the course path for the data points adjacent which are spaced a predetermined distance from a   data point detected immediately before.   3. System for producing a model according to claim 2, characterized in that the calculation means (32) further comprises a first set of instructions for controlling the operation of the means for generating coordinates of data.   4. System for producing a model according to claim 3, characterized in that the set of instructions comprises: means for producing information representative of the block dimensions of a glass opening in a spectacle frame, in which said dimensions include the lengths of axes A and B, the dimension of the effective diameter and its associated angle, and the length of each radius and its associated angle for a predetermined number of data points detected along the path of the stylus; and   means (49) for printing the representative information of said dimension data.   5. System for producing a model according to claim 4, characterized in that the means for generating data coordinates (12) comprise display means (50) for displaying messages to an operator and requesting   information and to display the value of the dimension data.   6. System for producing a model according to claim 5, characterized in that the means for generating data coordinates (12) comprise: means (32) for encoding the dimension data in binary code words in digital format; and   transmission means (16, 92) for transmitting the digitally coded words to the cutting means (14).   7. System for producing a model according to claim 1, characterized in that the cutting means (14) comprise: a machining station (150); means (146, 152, 154) for routing the blank to the machining station; a knife (228) associated with the cutting means (14), the knife being adapted for rectilinear movement by going towards the machining station and away from it; and means (167) for fixing the blank at the level of the machining station for a rotational movement relative to the moving the knife.   8. System for producing a model according to claim 7, characterized in that the control means (126) comprise means for containing a second set of instructions for controlling the operation of the cutting means (14).   9. System for producing a model as claimed in claim 8, characterized in that the blank routing means (146, 192) comprises detection means for determining the orientation of the nasal side of the blank at the level of the machining station. 10. System for producing a model according to claim 9, characterized in that the blank is characterized by: a body of relatively thin rectangular shape provided with main faces high (100) and low (102) generally parallel, first and second side edges parallel to each other and opposite, and first and second end edges, parallel and opposite to each other and perpendicular to said side edges; a series of teeth (104) disposed along the first (106) and second (108) side edges to engage the conveying means for moving the blank in a direction parallel to these side edges; nasal side locating means (166) defining an opening extending through the body between said upper and lower faces and substantially in the vicinity of a first corner of the body at a predetermined distance from the first and second end edges and first and second side edges to allow a beam of energy produced by a light emitting source in the detection means (164) to pass through the opening to be detected by a photodetector (162) in the detection means when said opening and said energy beam are opposite; of the first means to. hinges disposed adjacent to the first end edge; second hinge means disposed adjacent to the second end edge, said hinge means being located near the first and second end edges and being adapted for valve engagement with said hinge means located near the first and second end edges of a similar blank, said hinge means being located near the first end edge of a first blank cooperating with the hinge means disposed near the first end edge of a similar front blank located adjacent to the first end edge to allow said blank and similar front blank to rotate relative to each other about a pivot axis of the hinge means associated with the first end edge , and said second hinged means being arranged near the second end edge of the first blank cooperating with the hinged means disposed adjacent to the second end edge of a a similar rear blank disposed near the second end edge to allow said blank and said rear similar blank to rotate relative to each other about a pivot axis of the hinged means associated with the second edge end, said pivot axis of the hinge means associated with the first end edge being coplanar with one of the upper and lower faces and said pivot axis of the hinge means associated with the second end edge being coplanar with the other of the upper and lower faces. 11. System for producing a model according to claim 10, characterized in that the blank comprises means for holding the blank and a model cut from the blank. 5 12. System for producing a model according to claim 6, characterized by a central database computer (Z68) for receiving said dimension data from several data coordinate generation means (12), said computer based on data comprising means for containing a third set of instructions, this third set of instructions comprising means for identifying each of the data coordinate generation means and correlating data received from the identified data coordinate generation means to find them again and then transmit them to the control means associated with the cutting means.   13. Method of manufacturing a model intended for a lens to be formed and then placed in an opening of a spectacle frame, the model being cut from a blank 20 in a computer-controlled apparatus, comprising a controlled knife, this process being characterized by the following steps: trace the opening of the lens in the spectacle frame and record a series of data points along the tracing path; calculating a set of coordinate data characterizing the dimension, the shape and the selected dimensional measurements of the opening of the glass, transmitting therein at least part of the set of coordinate data to the cutting apparatus; rotating the blank relative to the driven knife; and   controlling the relative movement between the rotating blank and the driven knife according to the coordinate data set to cut a model from the blank.   14. Method of manufacturing a model according to the   claim 13, further characterized by the step of transmitting the portion of the coordinate data set representative of the selected dimensional measurements to a printer.   15. A method of manufacturing a model according to claim 13, further characterized by the following steps: providing a first blank from a chain of blanks to the cutting apparatus in the region of the ordered knife; separating the first blank from the chain of blanks 10 to rotate it in the region of the driven knife; cut the first blank to form a model; and advancing the next blank through said chain of blanks to eject the template cut from the first blank.