Abstract:
A next processing pin is applied as a follow-on pin to a stone, wherein the stone is held by a preceding pin and fixed to the stone by way of a first adhesive bonding location. The preceding pin is separated from the stone. The follow-on pin is fixed to the stone by way of a second adhesive bonding location spaced from the first adhesive bonding location. The follow-on pin frontally receives a fluid adhesive at a spacing from the stone and the spacing between the adhesive-coated front end and the stone is reduced until the adhesive front end contacts the stone. The adhesive is hardened at the contact location as the second adhesive bonding location and heat is transferred by way of the preceding pin to the first adhesive bonding location A force component is exerted on the preceding pin to release the pin from the stone and to hold the stone with the next pin.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the U.S. National Stage filing of International Application No. PCT/EP2008/068243, filed Dec. 23, 2008, which claims priority to German Patent Application No. 10 2007 062 638.1, filed Dec. 23, 2007 and German Patent Application No. 10 2008 035 730.8, filed on Jul. 31, 2008, the disclosures of which are hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    Embodiments of the invention relate to an improvement in a production method for cutting and/or polishing gemstones. The original production method has been handed down over many centuries and has been tried and tested and proven worthwhile. 
       BACKGROUND 
       [0003]    Exemplary embodiments relate to applying a next follow-on pin as a handling or processing pin to the stone to be cut, which is previously held by a preceding pin which serves for example as a measuring pin in preceding measurements on the stone to adapt the geometry of the rough stone to be cut, in particular a rough jewel, in the best possible fashion to a shape to be obtained for a cut jewel, or vice-versa. 
         [0004]    The jewel, in its desired geometrically predetermined shape, should be utilised in the best possible fashion, with a reduction in the loss of rough volume (in particular it should be of a volume-optimised configuration). 
         [0005]    The procedure which has been tried and tested and handed down for centuries for cutting rough uncut jewels operates with a pencil-like holding pin and a normal wooden block which serves as an apertured board for insertion of the wooden pin, to the tip of which the rough uncut stone is fixed with a drop of resin, wherein insertion of the pin into the apertured board defines an angle of inclination which is required for the cutting operation and which is to be maintained as uniformly as possible in the cutting operation and later upon polishing. DE-U 85 04 419 (Landgraf) depicts this operation, for example on page 1, middle paragraph. It is only then that the cut and the fire of the resulting cut jewel can be achieved or improved. 
         [0006]    After cutting of the first half of the stone the wooden pin is released by the influence of temperature, in which case the resin softens and a pin-change procedure takes place in which the stone is held with another wooden pin which is to be freshly secured at a different location using the same procedure, also shown in Landgraf, page 18, FIG. 8 and page 19, last paragraph with the ideas of ‘changing cementing’ according to page 9, middle paragraph. For that purpose the stone is turned and on the wooden pin fixed thereto again fitted into the hole in the apertured board to be able to cut and polish the opposite side of the stone. 
         [0007]    That side also requires the highest possible degree of consistency of maintaining the angle for the facets to be cut, the apertured board making it possible to adjust the cut angles in a raster grid of half a degree. 
         [0008]    In the operation of changing pins in the foregoing sense, there is a change in the processing zenith, from the ‘northern hemisphere’ to the ‘southern hemisphere’ of the rough jewel to be cut. In that pin-changing operation the experienced operator is reliant on his own judgment, fingertip feel and his optical assessment to position the follow-on pin in the ‘pin-changing step’ at a location acceptable to him for the stone thermally released from the first pin, just as he is equally reliant in the ‘pin-fitting step’, that is to say applying the first wooden pin, on his own perception and experience. In that respect the relationship of the two pins to be applied does not involve a defined reproducible accuracy, or only that accuracy which the experienced cutter can bring to the first pin application step and the second pin application step. 
       SUMMARY OF THE INVENTION 
       [0009]    The object of the invention is to simplify and automate the operation of changing pins from a first pin to a follow-on pin and in that respect to achieve the accuracy required for automated processing when measuring and/or cutting and/or polishing to be able to retain co-ordinate systems for orientation and geometrical placement of the either rough, semi-cut or finished stone and transfer such systems in the pin-changing operation (in a computing or controlling process computer). 
         [0010]    To attain that object the invention provides methods and apparatus&#39; as described herein. Pins for measuring and processing the stones are provided. 
         [0011]    In that respect the pin-changing operation involves on the one hand changing from a measuring pin to a first follow-on pin as a processing or handling pin. The pin-changing operation in the sense of this object however also involves the change from a first handling or processing pin to a second handling or processing pin, to be able to process the other hemisphere (the profile opposite to the rondist plane of the stone which in that respect is still rough), in particular to be able to cut and/or polish it. 
         [0012]    The method of applying the next processing pin, referred to for brevity as the ‘follow-on pin’, begins with mounting or ‘fixing’ that pin to the either rough stone or to the stone which is at least half finished cut and polished. The application operation is effected by way of a second adhesive bonding location spaced from the first adhesive bonding location at which the old pin is still fixed as the preceding pin. 
         [0013]    Preferably the second adhesive bonding location is arranged on a surface portion of the stone which is defined in alignment with the axis of the first preceding pin but that geometrical relationship is not imperative. Placement of the new pin at an angle greater than or smaller than zero in relation to the pin which is still held makes it possible to predetermine the position of the stone to be processed relative to the new pin (first processing pin). When changing from the first to the second processing pin the preference is for axial alignment. 
         [0014]    The expression ‘fluid adhesive’ for the glueing or adhesive bonding location is intended to denote all possible materials which have glueing or adhesive properties, have a viscoplastic state and can set. Examples of temperatures at which the viscoplastic state occurs is the room temperature in which the equipment operates. Setting should occur to an extent which fixes the stone to the respective follow-on pin with sufficient adhesive force to be able to process and handle it in the sense of cutting and polishing it. Examples of such adhesives are resins as are usual at the present time. 
         [0015]    The fact that the various pins must perform different tasks means that they are geometrically different in configuration, thus in regard to the handling and/or processing pin and the measuring pin. Their transposition or interchange is referred to as the pin-changing step, in which case a preceding pin is changed for a next pin and in an intermediate condition the stone bears both pins, or arranged on the stone are two pins which are arranged with a respective adhesive bonding location and which would both be capable of bearing same but the pin is held and moved only on one of the pins, with a free-standing second pin. 
         [0016]    With a preceding pin as the measuring pin the next pin as the follow-on pin is the first handling or processing pin. If the other hemisphere of the stone is to be processed a first handling and processing pin is replaced by a second handling or processing pin, which can both be of the same geometrical configuration but which are arranged in opposite relationship (on the same axis) and therefore in surface-spaced relationship, temporarily both and for the processing operation only the pin which is arranged later and which remains in glued or bonded relationship on the stone, in contrast the previously arranged handling and processing pin is separated from that stone. 
         [0017]    The stone is firstly held to the preceding pin. The pin is also held to that preceding pin during the initiation of the change procedure (pin-changing operation). The follow-on pin, in the above-indicated sense, is arranged at a spacing from the location at which the preceding pin is glued to the stone, or vice-versa. For that purpose the follow-on pin receives at its front end a viscoplastic adhesive, in particular a resin or a kind of resin which can set. The follow-on pin is moved towards the application location on the stone with that adhesive—at a spatial distance different from contact-to-contact—until the above-mentioned axial front end of that follow-on pin and the stone touch. 
         [0018]    The movement towards each other can also take place in the reverse relationship so that in relative terms reference should be made to a reduction in the spatial distance of the stone and the coated front end of the follow-on pin. When both pins are placed on the stone the fresh contact location is hardened as the second adhesive bonding location. For example by thermal influence or by the influence of light from a ultraviolet (“UV”) source which is positioned with its beam on the adhesive bonding location. 
         [0019]    Positioning of the follow-on pin has the result that there is a change in the way in which the combination of both pins and the stone is held. 
         [0020]    The stone with two pins is now held by another holding device, for example a clampable jaw device or a chuck, so that the old pin projects freely. The positioning of that old pin as the preceding pin under a heat-supplying source provides by thermal conduction for a feed of thermal energy to the first adhesive bonding location. The heat is preferably introduced by a hot air blower and a nozzle concentrating the hot air to act on the preceding pin and to be introduced by way of that pin into the first adhesive bonding location by thermal conduction. 
         [0021]    In that respect a further spacing is provided as a distance, meaning that the thermal energy predetermined by hot air does not directly influence the first adhesive bonding location, but with the interposition of the first pin and at least a portion of its geometrical length. Because the pin is in the form of a metal pin or comprises such a material which is metal-like and can conduct heat, the first adhesive bonding location is locally targetedly weakened and then softens. 
         [0022]    The adhesive bonding location which is weakened in that way and preferably also softened can now be separated off or released. 
         [0023]    Release is effected by applying a force component, for example a transverse force, acting outside the axial direction of the two pins, preferably perpendicularly thereto. That force component acts on the preceding pin as the pin to be separated off. With the release force, the weakened adhesive bonding location is physically released and the pin is separated from the stone, in particular in the form of simply dropping down in the case of a force acting vertically from above. Other directions for the release force are inclinedly from above or rearwardly along the axis in the form as a pulling force. 
         [0024]    The follow-on pin which was previously joined to the stone at the second adhesive bonding location still holds the stone and after that follow-on pin is gripped in a handling arm, preferably in a jaw device, the stone has not experienced any relative movement with respect to the one pin or the other, until the release or separation operation. 
         [0025]    Highly accurate transfer of the co-ordinate system applied in the stone can be effected in that way. The two placements of the adhesive bonding locations are exactly such that at no time can there be an inaccuracy in respect of such positioning and the precise geometrical axis through the two pins. That accuracy is provided in particular for all pin-changing operations. 
         [0026]    With the choice, which is in itself free of the first adhesive bonding location (for the measuring pin) and a presetting, controlled by the program system, for the second adhesive bonding location (first processing pin) as well as the third adhesive bonding location which is oriented in aligned relationship with the second adhesive bonding location on the axis of the pin (second processing pin), measurement is optimised and the sequence of processing the hemispheres is established. In that respect there is a certain dependency or influencing which cannot be directly predicted. 
         [0027]    The influencing effect firstly arises due to the appropriate presettings to be selected for the measuring pin and for the first processing pin. The measuring pin has a very thin application or mounting shaft with which it is to be fixed to the rough stone by a first adhesive bonding location. For that purpose, having regard to two criteria, a position is sought which is appropriate for the fixing in order then to have the greatest possible optical free space for optical measurement. For that purpose a location on the stone would have to be selected, which is of no interest in terms of measurement (as a blind spot results here) and which has a certain surface area in order to lie in a favorable position relative to the thin application pin and to be easily compensated by programming. As in the step of applying that measuring pin the stone is firstly considered in rough form without knowing what precise position a form of design will later have within the rough stone, the choice of an initially human worker cannot be directed to the entire production process or review it, but is firstly primarily concentrated on the initial task of good measurement and appropriately holding the pin for measurement purposes as well as ease of calculation (compensating for the blind spot by programming technology). 
         [0028]    After the measuring pin has performed its task, the rough stone has been measured and a processing pin is to be glued at a spaced location from the first adhesive bonding location, it is established how the first cutting operation proceeds. 
         [0029]    In that respect the processing pin is not necessarily arranged in axial alignment with the measuring pin, but primarily as is required by the following processing operation, and as the handling system allows in positioning of the processing pin. At the same time in that respect it is established whether the processing operation controlled by the program system (firstly primarily cutting of the tip end or the flat end of the design shape) is effected. In that respect the controlling program system can switch over and compensate. 
         [0030]    In that respect the feed of the first processing pin by a handling system is adjustable only in a certain angle, at any event less than three-dimensionally 180°, so that there is only a limited directional presetting, for tool reasons. Within that hemisphere, the application of the first processing pin is to be such that the first processing operation is on the flat side of the shaped jewel (the table side) or is effected from the point side of the shaped jewel (from the pavilion side). The position of the shaped jewel in the rough stone is only established after measurement and prior to that measurement operation the measuring pin was arranged so that those two associations are not always optimised with each other and are often dependent on the user feel. 
         [0031]    That unpredictability (randomness) can be compensated by switching over the program system for the cutting process, insofar as that program system establishes, whether cutting begins from the table side or from the pavilion side, and precisely from that side which is possible by virtue of the spatial factors involved and on the basis of the adjustment angle of the handling member which feeds the first processing pin. If application of the first processing pin is not possible at the location that the program system provides for the first processing operation from the table side, the program system switches over in the indicated fashion and moves placement of the first processing pin according to the position of the adhesive bonding location and the direction of the first processing pin into the other hemisphere relative to the rough stone in order firstly to be able to begin cutting from the pavilion side. 
         [0032]    The reasons why the first position which is actually reached cannot be reached by machine are machine limitations, collision with the measuring pin or the adhesive bonding location of the measuring pin. The program system then implements the change and compensates for the initially perhaps inappropriately selected placement of the measuring pin by way of the first adhesive bonding location. 
         [0033]    The first adhesive bonding location should therefore as flat as possible because it must be worked out in accordance with optical detection by the program technology as a blind spot which is to be replaced by a surface contour that is as simple as possible. The follow-on pin, that is to say the first processing pin, should in contrast be arranged perpendicularly to the (optimised) rondist plane. That application in accordance with position and direction is already a consequence of the calculation and the position of the shaped stone in the rough stone. In this case there are two directions which are displaced through 180° and which predetermine whether the table side or the pavilion side experiences the first processing operation. 
         [0034]    When applying the second processing pin to the third adhesive bonding location, in which case the rough stone is already half cut (from the pavilion or table side), the adhesive bonding location is oriented in precise axial alignment with the direction of the first processing pin which is still stuck to the stone, also calculated by the program system. 
         [0035]    Preferably release and subsequent separation of the ‘preceding pin’ is exerted by a free-standing edge or a leg. For that purpose either the edge can be moved against the (preceding) pin to be separated, or vice-versa, which movement is preferred. The edge is also preferably arranged close to the heat source so that there is no need for long distances for the movement of the holding device as the handling arm; particularly preferably the edge is arranged above the outlet for the hot air. 
         [0036]    In that case the stone is moved as a combination of stone and two pins arranged thereon until the time at which one of the two pins is released and separated off at the edge or the leg. A relative movement of the stone with respect to both pins does not take place after application of the new pin, until release or separation of the old pin. That period ensures accuracy of transfer or retention of the co-ordinate system for the stone. 
         [0037]    It will be appreciated that the effect of heat does not act straightaway but the first adhesive bonding location can be quickly weakened by virtue of a sufficient input of energy. For example the more strongly a blower of a hot air device acts on a pin to be separated off, and the better its thermal conduction in the longitudinal direction, the corresponding more quickly can the adhesive bonding location be weakened and also in particular also softened. 
         [0038]    The precise punctiform input of thermal energy into the adhesive bonding location without surrounding losses to the stone can ensure that the stone is not thermally loaded and in particular is not overloaded, which could reduce its quality and in particular could also entirely burn it. 
         [0039]    Although the application of heat to the pin involves a certain time delay caused by thermal conduction, it is possible to prevent the stone suffering from thermal shock so that thereafter it can no longer be cut. In a cutting operation after such a thermal shock it would split or break. 
         [0040]    Preferred materials for the pins for measuring or processing or handling are all kinds of metals and metal alloys, particularly preferably brass. 
         [0041]    Other ways of applying thermal energy are the application of current through a portion of the pin, the introduction of magnetic fields with eddy currents in the pin and transmission of the thermal energy produced thereby, like also finally contact with a thermally hot article. 
         [0042]    Optimisation trials have shown that, with a blower of a hot air device, a time of not more than 40 seconds, preferably less than 20 seconds, is required for the measuring pin to introduce sufficient thermal energy into a pin to release the adhesive bonding location. The temperature is between about 80° C. and 100° C. whereby the stone (jewel) is not thermally excessively loaded, but at the same time the forces still required in shearing off the pin do not become excessively great. 
         [0043]    The thermal energy introduced is propagated by thermal conduction in the pin to the adhesive bonding location which in that way can be thermally weakened in spot-accurate relationship. It will be appreciated that in that case the thermal energy is passed practically exclusively in the longitudinal direction of the pin (which is to be separated off). It can be mentioned in that respect that the first pin to be separated off is firstly the measuring pin, that is to say that which served to measure off the stone and which served for associated accurate holding thereof. 
         [0044]    When the stone then experiences the first processing stage, the measuring pin is no longer required. The remaining adhesive residue at the first adhesive bonding location which remains after the measuring pin has been separated off is removed in the cutting operation. 
         [0045]    When the pin passes into the second processing operation the other hemisphere is processed, to which the preceding handling and processing pin is fixed. That fixing is then to be released and the fresh application of a further handling or processing pin is effected in the way as described hereinbefore and claimed in the claims, by thermal weakening of the adhesive bonding location of the first handling and processing pin, the mechanical release force component, preferably in the form of a transverse force, and release and subsequent separation of the first handling and processing pin that is now no longer required, wherein the second handling and processing pin has been previously attached at the oppositely disposed location of the surface of the stone, as was described hereinbefore with a more general position for the first handling or processing pin which was adhesively bonded in the region of the opposite hemisphere in alignment with the normal to the table plane. 
         [0046]    In regard to the minimum length of the spacing at which the heat is introduced into the pin intended to be released, measurements and trials have shown that that location should occupy at least half the length of the pin to be separated. As the pins themselves can be of a very different length, to protect a valuable jewel it can be said that the spacing should be at least 2 cm and thermal conduction can occur over that 2 cm, for thermally softening the adhesive bonding location. 
         [0047]    By virtue of the different working operations to be effected with the pins the front ends of the pins are of different configurations. The measuring pin has a front which is of the smallest possible area, with little area or cross-section, in order to cover as little as possible of the stone which is firstly to be measured. 
         [0048]    If handling and in particular processing is required a larger area at the front end may be appropriate to be able to apply higher forces for cutting and/or polishing so that the handling or processing pin should be of an area of greater than 4 mm 2  at its front end. 
         [0049]    The measuring pin should preferably be smaller than 3 mm 2  at its front and the areas of the front ends of the two different pins should preferably differ by greater than a factor of 2. 
         [0050]    The different functions to be implemented by the at least two pins used for holding the stone define their geometry, in which respect they are not completely different but not more than half. The measuring pin for measuring off the stone serves to hold the stone to measuring it off in a measuring station in such a way as to establish a co-ordinate system that that stone bears for further processing and is and remains associated therewith from the computer. The handling pin, in particular also for processing in the sense of cutting or polishing, takes over the measured stone for the above-mentioned further handling thereof, in particular processing. For that purpose the handling or processing pin is of a particular configuration at a front end. 
         [0051]    A further handling or processing pin provided for processing the opposite hemisphere of the stone can look just the same. 
         [0052]    The measuring pin and the processing pin have an identical rear portion so that both pins can be serviced, gripped and set down by the same handling systems. That purpose is served by the intermediate portion having for both pins a gripping zone which can be gripped with a handling system, in particular a gripper arm having front jaws which are displaceable in parallel relationship, and can be clamped between the jaws. The pins are different above the gripping zone while the pins can be the same beneath the gripping zone. 
         [0053]    A circumferentially symmetrical gripping zone is provided as the gripping zone. It extends over the entire circumference of an intermediate portion which is assumed to be round so that the pin can assume any circumferential position in a store from which a handling arm would seek to remove it. A circumferential groove-shaped notch is particularly preferred. That allows the jaws of the handling arm to have projections with which they can engage into the notch in any rotational position of the pin. 
         [0054]    An identification mark is also provided in respect of both pins, being identical, which allows the rotational position of the pin to be reproducibly detected or to be recognised with measuring systems. In particular that marking is a radially extending leg, also referred to as a radial leg. In that way a system which knows the co-ordinate system of the stone can set itself to the lying or standing pin orientation which is precisely involved in the process at that time, for example by co-ordinate transformation, based on the marking. 
         [0055]    The marking is oriented from the gripping zone towards the front side (or front end), which configuration is preferred, so that the measuring pin and the processing pin are also of the same configuration in that respect. 
         [0056]    The respective holding portion which is the portion at the front end is of a different configuration. The respective shaft portion is preferably of the same configuration, which is arranged on the opposite side of the gripping zone. 
         [0057]    The holding portion in the processing pin is at least portion-wise conical, the conicity extending towards the front end. The conicity serves to reduce the diameter of the gripping portion (gripping zone) towards the front end which is applied to the stone by way of the adhesive. 
         [0058]    The application area in the case of the processing pin is at least 4 mm 2 , preferably larger. The adhesive is applied to that surface in order then to be adhesively fixed to the stone and hardened. 
         [0059]    For a particularly large application area, the holding portion can also be in the form of a double cone. Firstly the diameter is reduced from the gripping zone along the first cone, then the holding portion increases in thickness again towards the front side so that the double cone over the length of the holding portion affords a constriction or narrowing, with a large adhesive surface area. 
         [0060]    So that the handling devices can well grip the two pins the intermediate portion as the gripping zone is particularly pronounced. It is of a diameter larger than all other portions. That means that transversely relative to the axial direction the extent of the shaft portion and the holding portion is smaller than the transverse dimension of the intermediate portion. In the case of a round pin that interpretation can be applied to the diameter. 
         [0061]    In the case of the measuring pin the holding end is also at least portion-wise of a conical configuration towards the front end in order to narrow from the gripping zone which is larger in the transverse dimension, towards the front end. The conical configuration is however substantially more markedly pronounced than in the case of the processing pin and in particular there is no renewed increase in diameter towards the front end but rather the front side (which is equivalent to the front end) is provided with an area no larger than 3 mm 2  as the application surface for the stone. That concerns the holding end in the front portion in front of, or above the gripping zone. 
         [0062]    A set comprising at least one pair of measuring pin and processing pin is used for overall processing and measurement of a stone. In that respect the configuration of the measuring pin and the processing pin can be as described hereinbefore and claimed. In general however a plurality of stones is arranged on a plurality of measuring pins in order to be ‘stored’ or deposited with their shaft portions in a register until they are engaged by the handling arm at the respective gripping zone and fed to a process for optical measurement (for brevity: measurement) or to the pin-changing operation after a measurement procedure. 
         [0063]    The set is therefore not to be restrictively interpreted so that not more than one measuring pin and processing pin are used, but at least one in each category is put to use in the overall procedure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0064]    The invention is described in greater detail hereinafter by means of a number of embodiments by way of example with reference to diagrammatic drawings: 
           [0065]      FIG. 1  shows a form of an uncut stone with a geometrical form  1   a  arranged therein of a cut jewel, the outside dimensions of which lie entirely within the outside dimension of the stone in the rough form  1 . A trillion form is shown in the example. 
           [0066]      FIG. 2   a  shows a second form of an uncut rough stone  2  embedded with a second cut stone which acts in right-angled relationship and which has an emerald form  2   a.    
           [0067]      FIG. 2   b  shows a further form of an uncut rough stone  2  with embedded ground design form (intended) which acts in rectangular relationship and which is thus afforded by the program system. 
           [0068]      FIG. 3   a  shows a first handling or processing pin  20 . 
           [0069]      FIG. 3   b  shows a first measuring pin  10 . 
           [0070]      FIGS. 3   c  and  3   d  show a second handling or processing pin  30 . 
           [0071]      FIG. 4   a  shows the first measuring pin  10  with an uncut stone  3  arranged thereon by way of an adhesive bonding location  11 . 
           [0072]      FIG. 4   b  shows the same measuring pin with another uncut stone  4 , connected by way of the adhesive bonding location  11   a  to a front end of the measuring pin. The pins in  FIG. 4  are turned through 90° (this can be seen from the identification mark  15 ). 
           [0073]      FIG. 5  shows handling of an uncut stone  5  on a measuring pin  10  with a coating device  8 . 
           [0074]      FIG. 6   a  shows a row of a plurality of measuring pins  10  which each bears a different shape of a rough stone (for example in the sense of an uncut jewel) and in that case are releasably fitted with their lower pin ends (shaft) at spacings on a common carrier bar T in order to be able to be removed therefrom. The stones  3 ,  4  and  5  are shown from the preceding Figures. 
           [0075]      FIG. 6   b  is a further view of still further uncut stones which were already coated with a thin application layer and in that case respectively held by a measuring pin  10 . The adhesive bonding locations at the underside of the respective uncut rough stone are particularly apparent, in conjunction with the respectively reduced-thickness front end of the respective measuring pin. 
           [0076]      FIG. 7  shows the handling or processing pin  30  from  FIG. 3   c , which is removably held by a storage plate  40  in an opening, wherein a gripping device  50  with two jaws which can be moved apart engages a peripherally shaped holding zone  33   a  to remove the handling or processing pin  30  from the holding device  40  or—not shown—to fit therein one or more of those holding pins  30  to temporarily store them, wherein the handling or processing pin still bears no stone at its front end  34   f.    
           [0077]      FIG. 8  shows the same handling or processing pin  30  of  FIG. 7 , fitted into a clamping or jaw device  76  of a handling arm  70 , wherein an application device  60  applies a liquid adhesive  31  by way of a nozzle device  61 ,  61   a  to the enlarged front ‘tip’ of the handling or processing pin  30 . 
           [0078]      FIG. 9   a  show the approach movement of the handling or processing pin  30  to the handling arm  70  (towards the right in the drawing) and with a front-applied adhesive  31  in the direction of a stone  3  which is held by a measuring pin and which is held and positioned gripped in another handling device  78  in a chuck  79  thereat on a rear shaft. A hardening device  80  operating with light can be seen with its optical fibers  81 ,  82  at that location at which the handling and processing pin  30  (as the follow-on pin) is to be applied with its front adhesive  31  to the stone  30 . The movement of the handling arm  70  occurs theretowards. 
           [0079]      FIGS. 9   b  and  9   c  show different directions for applying the follow-on pin. 
           [0080]      FIG. 10  show the handling arm  70  with gripped therein one of two pins  30 ,  10  which hold between them by way of a respective adhesive bonding location  11 ,  31  the stone  3  which is unprocessed but which is coated with an opaque surface. Both adhesive bonding locations  11 ,  31  are still active and non-released. 
           [0081]      FIG. 11  shows the same arrangement in  FIG. 10  with the handling device  70  which has moved the two pins and the stone  3  under a hot air device  90  which is directed towards the shaft  12  of the measuring pin  10 ; shown above that placement is a knock-off edge  94  which is placed immovably beside the conical portion of the hot air device  90 . 
           [0082]      FIG. 12   a  shows the handling arm  70  as after release and separation of the measuring pin  10  and hardening of the adhesive bonding location  31 , it places the uncut stone  3  on a cutting disk  100  moved at a high speed of rotation. The handling and processing pin  30  is gripped in the handling arm  70  or the chuck  76  thereof. 
           [0083]      FIG. 12   b  shows the progress in processing, in which the same arrangement as illustrated in  FIG. 12   a  is involved, and the handling and processing pin  30  holds the stone  3  to be cut, in the cutting operation, and in that case the surface of the stone is produced by removal of the coating and the formation of facets on the cutting disk  100 . 
           [0084]      FIG. 12   c  shows a polishing operation after the cutting operation in  FIGS. 12   a  and  12   b.    
           [0085]      FIG. 13  shows an overview of the program system PS which controls the installation. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0086]    Referring to  FIGS. 1 and 2 , shown therein are various rough stones  1 ,  2  which also occur in the other examples as rough stones  3 ,  4  and  5 . They each appear there in different forms, wherein  FIG. 6   a  shows different forms of uncut stones, in particular rough gems, and  FIG. 6   b  is a side view. 
         [0087]      FIGS. 1 and 2  show how a form of a geometrically defined cut stone is introduced into an existing rough stone of a random configuration. Those forms  1   a ,  2   a  are to be placed in the best possible fashion there so that as little volume as possible of the valuable stone is lost when the stone is held, measured, handled and processed on the various pins to be described. 
         [0088]      FIGS. 3   a  and  3   b  show two representatives of different pins. The pin  20  is a first handling or processing pin and the pin  10  is a first measuring pin. Another form of a handling or processing pin is the pin  30  as shown in  FIGS. 7 ,  8  and  3   c.    
         [0089]    The measuring pin  10  has a first shaft  12  and a thinner application or mounting shaft  14  with which it is fixed to the stone  3  by an adhesive bonding location, see, for example,  FIGS. 4   a  and  4   b . For that purpose the measuring pin narrows from a gripping zone as a gripping portion  13  to the application shaft  14 . Preferably there is a conical portion which goes from a larger diameter to the smallest possible diameter for applying holding forces at the front end  14   f . The cone portion  14   a  is integrally connected to a lug portion  15  which connects to the gripping portion  13 . 
         [0090]    Provided in the gripping portion  13  is a circumferential groove-shaped notch line  13   a  which corresponds in shape and cross-section to a corresponding notch line  23   a  of the handling pin  20 . Both pins have to be handled and the handling devices can receive the measuring pin and the processing pin  20 , move them and set them down again at a suitable location. For that purpose they grip the gripping zone with a suitably shaped projection. 
         [0091]    The gripping zone is of a larger diameter than the other portions of the pins  10 ,  20  and  30 . 
         [0092]    The first processing pin  20  has a front portion  24  which is substantially longer than the holding portion  14  in  FIG. 3   b  and which narrows in the course of its extent to a front surface portion  24   f  on which an adhesive  21  for producing an adhesive bonding location on the stone  3  is symbolically illustrated. That pin  20  also has a lug portion  25  in an integral transition from the described longer portion  24  to the gripping portion  23 , in which the circumferential notch  23   a  is provided, for example in the form of a V-shaped or U-shaped groove which extends in circumferentially symmetrical relationship. 
         [0093]    Provided at the opposite end is a shaft  22  which is of the same configuration as the shaft  12  of the measuring pin in  FIG. 3   b.    
         [0094]    Both pins are of substantially identical configuration in the lower region and in particular the measuring lugs  25 ,  15  are harmonised (of equal width at least in the circumferential direction) so that on the basis of those lugs it is possible to establish the relative position of the pin to infer therefrom the relative position of the stone  3  arranged thereon by means of the adhesive bonding location. They serve for marking or for associated recognisability of the position so that they are functionally referred to as the ‘marking portions’. 
         [0095]    The other alternative of a handling or processing pin, hereinafter for brevity referred to as the processing pin  30 , is shown in  FIGS. 3   c ,  3   d ,  7  and  8 . The lower portion  32  is again comparable. In this case also the holding zone  33   a  is in the form of a circumferential notch placed in the gripping portion  33 . The lower shaft portion  32  cannot be seen in  FIG. 7  as it is fitted into the receiving means of the holding plate  40 . 
         [0096]    The front portion  34 , corresponding to the longer portion  24  in  FIG. 3   a , here comprises a base and two substantially conical portions  34   a ,  34   b , oppositely directed, providing a narrowed zone  34   c  in the intermediate region of the portion  34 . In that way the front portion  34  can perform two tasks, it can narrow from the gripping portion  33  and at the same time it can have a front  34   f  having a large area to be fixed to the stone  3  with a clearly defined adhesive bonding location in good holding relationship and capable of carrying high forces. A radial leg  35  forms the marking portion arranged on the base  34   d  of the holding portion  34  and above the gripping portion as the gripping zone  33 . It has a respective annular plate  33   b ,  33   c  above and below the annular notch  33   a.    
         [0097]    The resulting narrowed zone  34   c  can be displaced further upwardly or downwardly. 
         [0098]    Each of the handling or processing pins  20  or  30  hold a stone  1  through  5  with the first holding portion, are themselves held with the shaft portion  32  and have an intermediate portion which is larger in the extent transversely relative to the axial direction  100  than the largest transverse dimension of the first two portions. The respective intermediate portion as a gripping zone is of a circumferentially symmetrical configuration. An identification mark is provided on the side, remote from the shaft portion  22 , of the intermediate portion, as a gripping zone. The holding portion for the stone has at least portion-wise towards the front (towards the stone) a conical configuration with at the front end a stone application surface which is at least 4 mm 2  in area. 
         [0099]    The measuring pin  10  is also provided with a first shaft portion  12  for gripping the measuring pin, an intermediate portion  13  and a first holding portion  14  with a front  14   a , wherein in the extent transverse relative to the axial direction the intermediate portion  13  is larger than a transverse dimension of the other portions  12 ,  14 . 
         [0100]    The circumferentially symmetrical gripping zone  18  and the identification mark  15  are also provided and are of the same configuration as in the case of the processing pin. Only the holding end  14 ,  14   a  which is at least portion-wise conical towards the front end has an application surface  14   f  at the front end for the stone, which is not more than 3 mm 2  in area. 
         [0101]    The relationship of the application surfaces of the processing pin to the measuring pin is greater than 2, preferably substantially greater. 
         [0102]    The side view in  FIGS. 4   a  and  4   b  shows the mounted stone with an adhesive bonding location  11 ,  11   a  on the measuring pins  10  which are here of the same configuration. The different stones can be clearly seen once again in the rough stone register in  FIGS. 6 and 6   a . Their coating for neutralisation of the surface is effected in accordance with  FIG. 5 . 
         [0103]    Here, an applicator device  8  is used to apply a powder to the surface of the rough stone  5 , which renders its surface uniform and is opaque and preferably represents a white coating. That makes it possible to effect simplified measurement and more accurate optical measurement. 
         [0104]    The coating is of a maximum thickness of 1/100 mm (in the sense of 10 μm) but is not critical and should not be excessively great to improve measurement. 
         [0105]    The rough stones coated in that way are shown arranged in the register in  FIGS. 6   a  and  6   b  on measuring pins  10 , they can each be gripped at their gripping zone  13  in the circumferential notch  13   a  by a handling device and can be transported in the system for processing and machining. 
         [0106]      FIG. 13  shows an overview of the program system PS which controls the installation. The measuring station M measures the stone. The movable gripping device  50  moves the stone with measuring pin or the stone with handling or processing pin  30  (or  20 ) from and/or to a respective location. The respective one or a plurality of stones can be put into intermediate storage in the rough stone register in the form for example of a carrier bar T. A clamping or jaw device  79  holds the stone in the adhesive-changing step near the nozzle device  61 ,  61   a  and the UV hardening device  80 . A handling arm  70  holds and moves the stone on the handling or processing pin to the cutting operation S and the polishing operation P. An input system E having a keyboard and a screen allows the user to intervene and the program system PS controls the installation. 
         [0107]    Measurement and gauging M of the stones is described in detail here. It is to be assumed that the stones have been measured in a suitable optical measuring device in such a way that a co-ordinate system can be laid with one of its axes through the axis of each measuring pin  10 , which accurately describes the stone. That co-ordinate system is to be retained for further processing and its relationship with the axis of the measuring pin  10  and the marking of the measuring pin  10  which was described with reference to  FIG. 3   b  as a radial leg (lug)  15 , also applies for any further processing operation with a processing pin  20  or  30  which has a measuring lug  25  or  35  of the same configuration. 
         [0108]    In that sense the situation involves porting the stone from one pin to another, or interchanging the pin, and in so doing measuring the stone and then processing it twice, on each of its hemispheres. That is controlled by the program system PS shown in  FIG. 13 . The kind and manner of control is described in detail here and it should be appreciated that one skilled in the art can implement it in accordance with this description with current programmable components and elements. 
         [0109]    This handling description is set forth with reference to  FIGS. 8 through 12 , in which respect it is assumed here that the handling and processing pin  30  is used, which has a larger front surface  34   f  which in particular is also geometrically roughened, for example by concentric rings. 
         [0110]    Placed on the front surface  34   f  is an adhesive  31  which is firstly applied in liquid form by way of an applicator device  60 . For that purpose the applicator device  60 , provided with an adhesive storage means  63 , is moved to the front surface  34   f , or a handling device  70  with concentric jaws  76 , at which the processing pin  30  is gripped, is moved to the stationary adhesive device  60 . A narrowing nozzle  61  having a front end  61   a  applies a drop of adhesive, in particular in the form of a hardenable resin, to the surface  34   f , which can be appreciated by reference to  FIG. 8 . 
         [0111]    The processing pin  30  provided thus with an adhesive spot  31  is further moved to the handling arm  70  as shown in  FIG. 9   a . In that case it is moved to a stone  3  which is already gripped in another handling arm  78  and which is still fixed to the measuring pin is  10  with an adhesive bonding location  11 . That measuring pin  10  is fitted in a further chuck  79  (chuck provided with clamping jaws) and waits in the working region of a UV hardening device  80 . 
         [0112]    The movement of the handling arms  70  in  FIG. 9   a  towards the right goes to the point at which the adhesive spot  31  with the still hardenable (viscoplastic) adhesive bears against the vertically oriented front surface of the stone  3 . In that case the spacing between those two objects is reduced, which is preferably effected by movement of the holding arm  70 . When the point of contact is reached the adhesive  31  adheres to the processing pin  30  and the front surface of the stone  3  at the fresh adhesive bonding location  31 ′. Briefly switching on a UV light beam for a few seconds for it to act on the adhesive bonding location  31 ′ provides for hardening thereof, for example by polymerisation. For that purpose there are provided two optical guides  81 ,  82  held by an upper arm and a lower arm  81   a ,  82   a  on a vertical carrier  83  to be able to cause the issuing free light beam to act from both sides of the adhesive bonding location  31 . To compensate for different sizes of stone the arms are displaceable together with a vertical carrier  83 . The light guides can thus be directed on to the adhesive bonding location  31 ′ at least with their ends from which the UV beam issues. 
         [0113]    That light action is not shown and can be replaced by other kinds of hardening devices, it only shows one example of fitting the new pin  30  as the handling or processing pin to the stone  3  which was previously held on the measuring pin  10 . 
         [0114]    In an intermediate condition, as shown in  FIG. 10 , both measuring pins  10 ,  30  are fixed to the stone  3  with a respective adhesive bonding location  11 ,  31 . The adhesive bonding locations are apparent as being upwardly curved portions in the drawing, while the markedly different diameters of the holding portions  14  and  34  of the two pins  10 ,  30  performing different functions are also apparent. The respective lug  15 ,  35  is also apparent, which does not have to be circumferentially precisely oriented relative to each other, which only has to be known to the control device in the relative circumferential differential position thereof in order to be able to transfer or carry over the co-ordinate system ported by the measuring pin  10 , to the handling and/or processing pin  30 . 
         [0115]    Upon a change from one processing pin to another, the axes are aligned. 
         [0116]    The axes  100  and  101  of the two holding portions  13 ,  34  are not in mutually superposed relationship in every case. For example, the axes are not in a mutually superposed relationship in the cases involving the change from the measuring pin to the first processing pin. 
         [0117]    Circumferential rotation of the measuring lugs  15 ,  35  relative to each other, as shown in  FIG. 10 , is also possible. They do not need to be axially aligned. The program system calculates that in the co-ordinate transfer procedure with the change in the pins. 
         [0118]    If the pins  30  are fitted at another angle the axes  100 ,  101  of the pins  10 ,  30  are at an angle of greater than or less than 0° relative to each other. That is achieved by a displacement of the handling arm  70  in the x-y plane and rotation of the stone  3  about the axis  101  with the clamping device  79 . In that way the location of application of the resin  31  as the adhesive bonding location  31 ′ and the angular position of the axes  100 ,  101  are established. They are in the free hemisphere, possibly limited in terms of three-dimensional angle to &lt;180° by tool influences or freedoms. 
         [0119]    The various orientations of the axes  100 ,  101  are shown in  FIG. 9   c , in which respect it is assumed that an axis  102  lies on the axis  101 , which axis  102  is the axis perpendicular to the intended table plane of the cut stone.  FIG. 9   b  shows the approach movement of the arm  70  which is pivotable in the x-y plane and which is movable without upward/downward inclinability along the path b. The arm  70  is also displaceable in the height direction z. To fit the pin  30  in the x-y plane the stone is so turned by the other clamping device  70  that the perpendicular  102  to the table plane of the stone comes to lie in the x-y plane. 
         [0120]    The program system suitably converts the co-ordinates or systems. An adjustable degree of freedom at the arm  70  can be eliminated therewith, which promotes accuracy and reduces the costs of that handling tool. 
         [0121]    The new pin  30  is now fitted. The clamping device  79  releases so that the measuring pin  10  comes free and there is now a freely projecting pin  10 , with its lower shaft  12 . 
         [0122]    The handling arm  70  with the second pin holds the combination as shown in  FIG. 10 . It moves that combination as shown in  FIG. 11  to a hot air device  90  which is illustrated there and which causes a hot air flow to act on the portion  12  of the measuring pin  10 , at an air connecting portion  91  having a front outlet  91   a . The action occurs directly at the outlet  91   a  and at the spacing ‘a’ from the adhesive bonding location  11 . The applied energy is passed into the adhesive bonding location in spot-accurate relationship due to thermal conduction so that the adhesive bonding location  11  is thermally weakened and in particular softened. After at the latest 10 seconds the adhesive bonding location  11  is so greatly weakened that a rearward-upward movement of the handling arm  70  and the jaw device  76  can initiate the operation of knocking off the measuring pin  10 . For that purpose the combination of two pins and a stone is moved rearwardly and upwardly in order to be loaded with a transverse force symbolically indicated by F q  at a knock-off edge  94  in the form of a leg or edge, on a leg of a corresponding longer configuration. 
         [0123]    Upon an upward movement of the arm  70 , a downwardly directed force component F q  on the shaft  12  of the measuring pin  10  causes that pin to be knocked off and thus provides for release of the already weakened adhesive bonding location  11 . In a further upward movement the pin  10  drops off entirely so that it is separated from the stone  3 , also due to the transverse force F q . Other directions of the releasing force component are a pulling force or inclined directions at angles of greater than 0° and less than 90° with respect to the axis. 
         [0124]    The resulting structure as shown in  FIG. 12   a  is a handling arm  70  with a jaw device  76  carrying the measured stone  3 . In this case the co-ordinate system has been transferred without a loss in accuracy and the control knows exactly in what rotary position and in what axial position the stone  3  is disposed with its geometrical extent, in a given position of the handling arm  70 . 
         [0125]    In  FIG. 12   a  the control system has moved that handling arm to a cutting disk  200  which is moved at the angular speed ω (omega). By corresponding movement of the stone  3 , a facet structure can be cut into the stone and in that case the remaining residue of the adhesive bonding location  11 , as shown in  FIG. 12 , can be removed. 
         [0126]      FIG. 12   c  shows polishing on a polishing disk  300 . The arm  70  on the chuck  76  holds and guides the stone  3  with the cut facet on the polishing disk. The relative rotary position and advance position can be measured by the marking  35 . 
         [0127]    The first processing operation is concluded by facetting and polishing of the first hemisphere of the stone  3 , as shown in  FIGS. 12   b  and  12   c.    
         [0128]    The second stage of processing the stone  3  as a follow-on from  FIG. 12   c  is not shown but is readily apparent from the context. 
         [0129]    In this case the processing pin  30  is replaced by another processing pin applied to the stone at the side which has already been processed. Application of the pin is effected as described hereinbefore for the pin  30 , wherein the follow-on pin can be of a different geometry at its front end, for example it can have a small recess, but not necessarily so. In that case the axes of the pins are congruent. 
         [0130]    When the stone  3  is also finished in its processing after processing of the other hemisphere on the opposite side in  FIG. 12   b  on the cutting disk  200  and the polishing disk  300 , separation of the last processing pin can also be effected. For that purpose a thermal influence is preferably also used, but not at a higher temperature, but cooling to below 0° C., preferably to −10° C., at which temperature the adhesive is released at the end of the stone that has already been cut so that the stone drops in the finished processed condition from the second processing pin. 
         [0131]    In the claims defining the exemplary embodiments appended hereto, reference numbers have been included. These reference numbers are not meant to limit the scope of the claims but merely to provide reference to the Figures showing the embodiments described herein.