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Publication numberUS3388843 A
Publication typeGrant
Publication dateJun 18, 1968
Filing dateJun 22, 1966
Priority dateJun 16, 1961
Also published asDE1421775A1
Publication numberUS 3388843 A, US 3388843A, US-A-3388843, US3388843 A, US3388843A
InventorsUmbel Forrest K
Original AssigneePittsburgh Plate Glass Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Glasscutting control apparatus
US 3388843 A
Images(8)
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Description  (OCR text may contain errors)

June 18, 1968 l F. K. uMBl-:L 3,388,843

GLASSCUTTING CONTROL APPARATUS Original Filed June 16, 1961 8 Sheets-Sheet 1 M44, M2? Kw4.,

June 18, 1968 F. K. UMBEL.

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June 18, 1968 F. K. UMBEL 3,388,843

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GLASSCUTTING CONTROL APPARATUS INV EN TOR.

June 18, 1968 F. K. UMBEL GLASSCUTTING CONTROL APPARATUS original Filed June 1e, 1961 8 Sheets-Sheet 5 .QQN\ ---is ILVIII! far/lays.

June 18, 1968 F. K. Umain.

GLASSCUTTING CONTROL APPARATUS 8 Sheets-Sheet 6 Original Filed June 16, 1961 June 18, 1968 F. K. UMBEL.

GLASSCUTTING CONTROL APPARATUS 8 Sheets-Sheet 7 Original Filed June 16, 1961 June 18, 1968 F. K. uMBl-:L 3,388,843

GLASSCUTTING CONTROL APPARATUS Original Filed June 16, 1961 8 Sheets-Sheet 8 V44, ma, #ffm United States Patent O 3,388,843 GLASSCU'ITING CONTROL APPARATUS Forrest K. Umbel, Verona, Pa., assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa., a corporation of Pennsylvania Original application June 16, 1961, Ser. No. 125,329, now Patent No. 3,274,390, dated Sept. 20, 1966. Divided and this application .lune 22, 1966, Ser. No. 559,525

11 Claims. (Cl. 22S-96) This yapplication is a division of application Ser. No. 125,329, tiled .Tune 16, 1961, now Patent No. 3,274,390, entitled Glass Cutting Control Apparatus.

This invention relates to control apparatus for directing the cutting of glass sheet or continuous glass ribbon into a number of smaller pieces.

In the manufacture of glass, the cutting process by which smaller useful sizes are produced from large sheets or continuous ribbon on a glass production line, entails cutting the glass transversely at different locations in a longitudinal, or Z direction to produce Z lengths of glass followed by slitting the Z lengths in the opposite transverse, or S, direction into rectangular pieces. The rst transverse Z cuts and the subsequent transverse S cuts are selected in view of desired Z by S sizes and the locations of defects in the glass, to partition the glass into usable rectangular pieces excluding the major defect containing glass areas.

In carrying out this partitioning process, it has been customary heretofore to manually direct the S cutting operation by which Z lengths of glass are slit into the final rectangular pieces. One object of this invention is to direct such a partitioning process such that the cutting of Z lengths into S widths is carried out completely automatically and in pace with the continuous glass production.

Another object of the invention is to set up the S cutter apparatus responsive to a record of S cut locations made on the Z lengths of glass.

Another object is to provide apparatus for detecting S marks on rapidly moving glass sheets and capable of distinguishing such marks from other opaque marks on the glass so as to insure that the S cuts are made only at the proper S locations.

Another object is to provide a control circuit operated by a plurality of photosensitive elements which circuit responds to simultaneous changes of state of selected ones of such elements.

One of the objects of the invention is to provide improved means for accurately synchronizing a series of record derived signals with the movement of the record.

Further objects will appear from the following description taken in connection with the accompanying drawings in which:

FIGURE 1 is a schematic view depicting `a glass production line and the ilow of glass along a conveyor and laterally on side line conveyors to the S cutter apparatus;

FIG. 2 is a diagrammatic perspective view of vthe S cutter apparatus;

FIG. 3 is a partial elevational View of the S marker apparatus;

FIG. 4 is a sectional View taken along the lines of 4-4 of FIG. 3;

FIG. 5 is a block diagram illustrating the components of the S mark detector control circuit;

FIG. 6 is a schematic wiring diagram of the S mark detector control circuit;

FIG. 7 is a diagram of the clock operating the S mark detector stepping switch;

FIG. 8 is a schematic wiring diagram of the S mark detector;

3,388,843 Patented June 18, 1968 Fice FIG. 9 is a partial elevational view with parts in section showing details of the S cutter apparatus;

FIG. 10 is a side view of FIG. 9 with parts in section;

FIG. l1 is a schematic wiring diagram of the S cutter control circuit; and

FIG. 12 is a chart illustrating different states of the clock stages.

While the invention has been shown and will be described in some detail with reference to one particular embodiment thereof, there is no intention that it be limited to such detail. On the contrary, it is intended here to cover all modifications, alternatives and equivalents falling within the spirit and scope of the invention as defined by the appended claims.

GENERAL ORGANIZATION Upon more specific reference to the drawings it will be seen that the invention is applied to apparatus ernployed in the manufacture of glass which may be in the form of sheets 128 wide and 180" in length, or in the form of a continuous ribbon of this same width. In general, the industrial apparatus illustrated provides means for partitioning the glass into usable, saleable sizes, excluding the major defect containing portions. To this end, as illustrated particularly in FIGURE l, which comprises an overall schematic representation of a glass production line and associated glass partitioning apparatus, the glass is conveyed from a source such as plate glass grinding and polishing apparatus (from right t-o left in FIGURE l) by means of a roller conveyor past inspection stations to a glasscutting apparatus for making successive transverse cuts lacross the glass sheet or ribbon width, herein called Z cuts. The glass conveyor is then speeded up to move or advance the Z lengths forwardly along the conveyor spacing such from the continuous ribbon glass or sheet of glass in the Z cutting apparatus. Such Z lengths of glass are then shunted onto side lines and into S cutter apparatus at a cutting berth in each side line wherein a set of second cuts, herein called S cuts, are made to slit or slice the Z lengths into smaller usable widths.

In the copending application, Ser. No. 850,360, now Patent No. 3,246,550, of William F. Galey, Joseph A. Gulotta, and Forrest K. Umbel, entitled: Length and Area Partitioning Methods and Apparatus, means is disclosed for automatically deciding the Z and S cuts required to evolve the maximum overall yield of usable glass considering the locations of defects in the sheets or ribbon of glass on a glass production line, such as shown in FIG- URE 1, in view of a programmed series of sizes. In carrying out this partitioning process, a secondary record is made of the locations lof defects appearing in the glass. Z and S cut decisions are made in the computer based on defect location information derived from the secondary record. The Z cutter is operated upon command of the computer responsive to such decisions. Still referring to FIGURE l, with the illustrative apparatus, also upon command of the computer, marks are placed on the Z lengths of glass as the latter move along the line, indicating the S locations of the S cut decisions. Thus, each glass sheet Z length has on its surface a record of the cuts required to completethe partitioning process, in the form of S marks, and such information is carried along with the glass sheet as it moves downstream from the Z cutter toward the S cutter on that one of the side lines to which the glass Z length is selectively shunted.

For details of suitable means for making a secondary record of glass defects, reference may -be made to application Ser. No. 850,460, now Patent No. 3,191,857, 0f William F. Galey and George W. Misson. As described in detail therein, in order to provide the requisite information as to defects appearing in the glass, which information is stored 'in the secondary record and used in deciding the partitioning of the glass, the glass may be first manually inspected for the presence of defects, or, alternatively, `the glass maybe optically inspected at inspection stations upstream of the Z cutter. With manual inspection, -those defects of such severity as to atect the quality of the glass are dimensionally located by marks placed on the glass. Such defect marks are detected by photosensitive vdevices mounted over the glass line and dimensional information as to such defect marks is transferred from the detectors tol defect storage apparatus for making a secondary record of defect location. While the present invention is not limited to the particular defect detection, defect storage, or Z and S cut computing apparatus hereinbefore described, this invention has particular utility in an automatic glass partitioning apparatus including such components. Turning, therefore, to details of certain portions of the apparatus previously generally described, the S marker construction and operation has particular significance and cooperation with the present invention as will appear from the following.

S MARKER Following each computing cycle during which the computer considers the demand program of Z by S sizes and chooses the sizes that give the preferred lit, the Z cutter is operated upon command by the computer to make the successive Z cuts. In order to makey the longitudinal S cuts on which the calculations depended for choosing the Z 'by S sizes and the Z lengths, without interferring with the ow along the conveyor, the severed Z lengths of glass are marked for the S cuts before being shunted onto side lines for cutting by suitable slit or S cutting apparatus. Referring to FIGURES 3 and 4, a preferred means is there shown for placing the S marks on the Z lengths of glass. As hereinbefore mentioned, reference may be made to application Ser. No. 850,460, of William F. Galey and George W. Misson, now Patent No. 3,191,857, entitled: Glass Partitioning Process and Apparatus, for details of a suitable S marker apparatus.

As indicated Idiagrammatically in FIGURE 1, the S marker apparatus is carried on a fixed bridge over the conveyor and is connected by cable to the computer for.

transfer of the command signals. In this partitioning process the glass is cut in yboth the Z and S directions to dimensions which are integral multiples of 2". Where the glass on the line is 128 in Width, in the present illustrative case, the bridge 10 carries sixty-three individually operable markers 12 for placing marks on the glass vdefining locations for S cuts at each 2 spacing across the glass. It will be understood that provision may be made for marginal trim cuts of different widths; however, for present description purposes it will be considered that with sixty-three markers all requisite S marks may be made, and an R and a sixty-fourth marker are provided, one at each end of the S marker row, for making reference marks designating the edges of the sheet. While the spacing of the markers may be varied as desired, it is advantageous to have the spacing between markers as small as the mechanical considerations permit so that the marks appearing on the glass may be located in a narrow band to gain time in the S mark detection and control of the S cutting apparatus. In the present case, the markers, including the R and sixty-fourth reference markers, are mounted on 11/2 centers so that the spacing be-tween S marks on the Z length of glass is in multiples of 11/2". It will be readily understood, furthermore, that while the present apparatus is constructed to operate with 2" `as the basic dimensional unit for measuring Z by S sizes, another dimensional unit may be used as desired with suitable mechanical and electrical circuit modilications.

Referring to FIG. 4, each S marker includes a crayon l t vassess-i holder pivotally mounted on the bridge 10 by means of a shaft 14, so that the holder may be moved from a normally raised position (shown in dashed lines in FIG. 4)

'wherein the tip of the crayon is above the glass, to a marking position (in solid lines in FIG. 4) wherein the tip of the crayon is in glass contact, the movement of the glass producing a mark thereon. The holder for the crayon is normally positioned to maintain the crayon above the glass by a solenoid operated latch 16. In the present case the holder is yieldingly biased towa-rd the marking position by a spring 18. The position of each holder may be adjusted to move the crayon toward the the glass marking position by a cam 20 once the solenoid 22 has operated the latch 16 to release the holder. Individual earns 20 are provided for each holder and are rotated through successive positions of a cycle by a hydraulicmeans 24 connected to a shaft 26 carrying the cams. The solenoid 22 provided for the latch of each holder, is connected individually to the computer so that the command to make an S mark in a particular S location is transmitted from the computer through the con-y nection to the solenoid associated with the marker at that S location.

S CUTTER APPARATUS Now referring to FIGS. 2, 9 and 10, a suitable means for cutting the Z lengths of glass into usable widths, referred to herein as the S cutter, is mounted between continuous sections of each conveyor side line to receive individual glass Z lengths. For details of a suitable S cutter apparatus, as above mentioned, reference can be made to Patent No. 3,146,926 of Charles O. Huiman, George W. Misson and William F. Galey, entitled: Glass Cutting Apparatus. In the present case, such cutting apparatus includes a table 30 in the form of a plurality of spaced conveyor belts 32A-32P aligned longitudinally with the side line and separating the incoming side line conveyor section 34 from a following conveyor section 36. The glass Z length is delivered by the incoming side line conveyor section 34 onto the table 30 where the glass sheet is clamped for the usual scoring and snapping glasscutting operations. A carriage 37 movable transversely of the table and glass Z length carried thereon from a home position shown in FIG. 2 to an away position at the opposite side of the table carries sixty-tive individual scoring devices 38-R to 38-64 mounted on 2" centers the full length of the carriage. Each scoring device 38 is thus mounted at the location to score the glass sheet for an S cut and 2" from the adjacent S cut scorer. In the operation of the S cutter, selected scorer devices 38 are lowered into glass contact and a full set of score lines is made during travel of the carriage between its home yand away positions; subsequently, the glass sheet is snapped at each score line to make the S cuts.

Turning now to details of the scoring devices, referring also to FIGS. 9 and 10, each scoring device 38 includes a scoring wheel 42 pivotally mounted by a lever 44 which s normally held by a latch 46 above the glass. Actuation of the associated solenoid R-SOLV to `64-SOL raises the latch 46 allowing a spring 48 to pivot the lever 44 and lower the scoring wheel 42 into glass contact. The solcnoids R-SOL to (S4-SOL are selectively actuated by control means hereinafter described in detail.

Below the table 30 (FIG. 2) and located so as to be under the carriage with the latter in the away position is a row of snapping devices 50-R to 50-64. Each snapping device 50 has a snapping head or caster 52 which may be rai-sed into glass contact. To this end each snapping device also has a hydraulic cylinder 54 operated by a solenoid valve R-SV to 64-SV, the hydraulic cylinder being connected to raise the head of the snapping device against the bottom surface of a glass sheet on the table after the sheet has been scored by selected scoring devices during travel' of the carriage to the away position to run each cut along the score lines in the glass. For

cooperation with the snapping devices 50, the carriage 30 carries resilient fulcrum elements 58 which are positioned between each of the scoring devices 50.

Accordingly, a program of S scorer solenoids R-SOL to 63-SOL is actuated with the carriage at its home position on one side of the side line, thereby setting up the scoring devices while the Z length of glass is run into the cutting berth. The glass Z length is scored for all S cuts by driving the carriage, by means of a hydraulic motor, across the glass with all scoring devices of the S cut program or series in glass contact to produce all the score lines. T he carriage is driven to its away position wherein the scorers are located past the edge of the glass sheet as shown in FIG. 10, and with the carriage in said position the snapping devices are successively operated to snap the glass sheet at each score line starting with the first snapping device Sil-R adjacent the left side of FIG. 2 and the following conveyor section 36, and continuing with each successive snapping device until all score lines have been snapped. As each snapping device is hydraulically operated, the caster or head 52 which is between adjacent fulcrum elements 58 lifts the edge of the glass upward into contact with such fulcrum elements. When a score line is present the snapping head under the glass is aligned with the score line and the upward pressure by the head in cooperation with the fulcrurn devices breaks the glass, starting the cut which runs across the sheet following the score line. After the scoring and snapping operations have been completed for an entire glass sheet in the S cutter, the individual widths of glass are run out of the cutting berth onto the following conveyor section 36 and removed from the table by operating the table belts 32A-32P. The carriage 37 is subsequently returned to its home position to await the delivery o-f a succeeding Z length of glass.

Reference is also made to FIG. 1l, a schematic diagram of the S cutter control circuit. The scorer solenoids R-SOL to S4-SOL are shown at the right side of the diagram connected between 115 volt AC buses 70 in series with relay contacts R-CR to 64-CR. The buses 70 are energized fro-m a 115 volt AC source through switches, not shown, which are closed by a glass Z length moving into the S cutter and are opened following the cutting operation. The scorer solenoids are energized when S relays R-CR to odi-CR are actuated either manually to insert a program of S cuts, by means of push button switches R-PB to 6ft-PB, or in accordance with a series of S marks on the glass Z length moving into the S cutter. In the latter case, according to this invention, by means described hereinafter in detail, a stepping switch is driven in synchronism with the movement of the glass Z length into the S cutter. S mark signals are transferred through the wiper 72 of the stepping switch to the appropriately numbered S relay R-CR to 64-CR to set up the scorer devices.

When an S relay R-CR to tid-CR is energized by one of the push buttons R-PB to dfi-PB or through the stepping switch, holding contacts 74-R to '74-64 are closed to seal in the relay coil. The scorer solenoid R-SOL to 64I-SOL thereby remains energized after the wiper 72 passes the same numbered contact. After the Z length is in the S cutter, means (not shown) may be provided to align and clamp the glass sheet, following which the carriage 37 with the actuated scorer devices is driven across the table 3@ to score the glass sheet. When the carriage reaches its away position, it is stopped and a snapping device stepping switch at the lower part of FIG. 1l is actuated to operate the snapping devices StB-R to Sti-64 in sequence. Thus the switch 75 is closed by suitable mechanism after the carriage 37 reaches the away position to energize the circuit of the snapping device stepping switch, and the wiper of the latter is driven to its successive positions to run the cuts previously scored. Suitable circuit switches and protective devices will be included to obtain the desired specific order of operations and at the desired speeds, as will readily be understood.

S MARK DETECTOR CONTROL CIRCUIT In accordance with the present invention the S cutter apparatus is set up automatically by the S marks on a Z length of glass, which serve as a record of the S cut decisions. To this end, an S mark detector is mounted above each side line conveyor 34 ahead of the S cutter and adjacent a marginal edge of the conveyor over the series of S marks on a Z length moving into the cutting berth.

As shown in the block diagram of FIG. 5, signals from the S mark detector are conveyed through a signal storage network and an S mark detector stepping switch to the S relays of the cutter apparatus. In keeping with this invention, the clock drives the stepping switch in synchronism with a Z length of glass passing the S mark detector. The first mark on the glass, a reference mark applied by the R marker of the S marker apparatus and representing the edge of the glass accounting for trim cuts, starts the clock operating when carried under the S mark detector by a glass Z length travelling toward the S cutter. It will be recalled that the S marker records the S cut decisions in the form of marks made on the glass at multiples of 11/2 spacings which represent, however, S cuts at multiples of the 2" dimensional unit. This control circuit is effective to expand the S record on the glass, scaled at multiples of 11/2, to the requisite 2" cutting scale. In the present case this is achieved by stepping the wiper 72 of the stepping switch to successive positions with each 11/2 of glass movement, so that after the first 11/2 of glass movement following the reference mark, the wiper is shifted to its reference R position; after the next 11/2 of glass movement the wiper is .shifted to its S-1 position, and so on, always lagging one step behind the glass movement. The S-l, S-2, S-3, etc., contacts of the stepping switch are connected to operate the l-CR, Z-CR, 3CR, etc., relays of the S cutter, respectively, to operate the same numbered scorer solenoids l-SOL, 2-SOL, 3-SOL, etc. It will be readily understood, therefore, that an S mark on the glass will produce a signal via the S mark detector which is stored in the signal storage network to avoid missing or misplacing S mark signals between contact positions of the wiper 72, and this signal is read out of the signal storage network and transferred through the stepping switch to the S relay having the same number as the S mark measured from the reference mark on the glass, thereby to operate the scorer solenoid having the same S number to score the glass sheet at that S location when the carriage 37 of the S cutter is operated. A series of scorer solenoids 1-SOL to 63SOL is thus set up to carry out the S cut decisions recorded as S marks on the Z length of glass.

As shown in FIGURE 1, it is preferred to operate the S marker to place marks on each Z length adjacent both its leading and trailing edges so that an S mark detector adjacent the same marginal edge relative to glass movement, above either right or left side line conveyors will be passed by a series of S marks.

In general, the S mark detector, which is shown in detail in FIG. 8, comprises a circuit which responds to an S mark passing photosensitive elements, herein shown as three aligned phototubes 80, 82, 84. Such phototubes are illuminated by a light source 86 mounted below the side line conveyor 34 such that any S marks intercept the light beams reducing the illumination of the phototubes. The phototube circuit responds with an output signal which actuates a suitable S mark signalling relay 88 closing its contacts 90, which are located in the signal storage network.

(l) S mark detector In carrying out the invention, the S mark detector is responsive to S marks on the glass and is capable of distinguishing such marks from spots or other opaque marks. Stating the function of the S mark detector in another way, where the S marks on the glass constitute bits of data and may be at 11/2 spaced data points within the band of S marks, the S mark detector is capable of producing signals denoting either the presence or absence of bits of data at each data point. For this purpose the S mark detector includes a plurality, herein shown as three phototubes 80, 82, 84, which are mounted over the glass side line conveyor 34 at a point ahead of the cutting berth and S cutter, as shown in FIGURE 1, and are closely spaced in alignment transversely of the direction of glass movement. The phototubes are located adjacent one margin of the conveyor above the S marks on a glass sheet thereon so that a line on the glass representing an S mark intercepts the light from below the glass illuminating all three phototubes producing, under such conditions, a reduction in illumination of all threephototubes. To discriminate between an S mark line and an opaque or dark spot on the glass, an S mark will be represented by dark signals simultaneously at any two of the three phototubes in the circuit, and will produce an output signal, while a dark signal at only one phototube produces no output signal.

Also referring to FIG. l, the first mark R on a glass sheet moving along a side line conveyor is a reference mark and represents the marginal cut to be made; other marks define the S cut locations in terms of the 2" diinensional unit; that is, S-17 represents 34" and S-35 represents 70 from the reference mark. Such S marks are shown for purposes of illustration, crowded into a band of marks on the glass wherein the marks appear at multiples of 11/2 spacings, and thus such marks are not at the actual locations of the S cuts to be made. With this arrangement to gain time in the S direction, all S cut information may be read from the glass sheet to set up the S cutter apparatus before the sheet is completely into the cutting berth. It will be understood that the S marks herein shown as lines may -be any opaque line or mark applied on the glass by means such as a washable crayon.

Still referring to lFIG. 8, the three phototubes 80, 82, 84 used in this preferred circuit are of the photo-resistive type, having a significantly lower resistance when illuminated; that is, when connected to a sourcey of DC operating potential conventionally shown as B+, and normally illuminated through a glass sheet by the light 86 below the conveyor. The resistance of such a phototube increases, representing a dark signal, responsive to a reduction in illumination of the phototube. The three phototubes 80, 82, 84 are each connected in a first circuit position in series with a resistor 92A to 92C, providing a first set of parallel resistors, and to ground, with each resistor having a similar resistance value to that of the initial (illuminated) resistance of the phototube. The same potential appears at the junction points between the phototubes 80', 82, S4 and the resistors 92A to 92C with the phototubes uniformly illuminated and such junction points are connected through condensers 94A to 94C to a second circuit portion including second and third sets of parallel resistors 96A to 96C, 98A to 98C, respectively, connected in series between a source of DC potential B+ which may be the same potential source energizing both circuits,y

and ground. For illustrative purposes, a satisfactory circuit is provided using resistors with a resistance value of 100K ohms for the first and second sets of parallel resistors, and resistors with a resistance of 200K ohms for the third set, where the initial (illuminated) resistance of the phototubes is 100K ohms.

The parallel resistors 98A to 98C of the third set are also arranged in series with a resistance 102 illustratively of about 2 megohms and a source of DC potential shown as B+ to operate a suitable signalling device, herein shown as a relay 88 in the signal storage network. This relay 88 is operated by a negative pulse reflecting a drop in potential in anyone of three conductors at points 104A to 194C responsive to a dark signal at any two phototubes.

To this end, the phototube circuit of FIG. 8 operates in the following manner. In the normal condition of the circuit, with all portions energized, when light from the source S6 is falling on all three phototubes, current flows from B+ through each phototube S0, 82, Sfrand the first set of resistors 92A to 92C causing the same potential to appear at the junction points there between and the left hand terminals of all three condensers 94A to MC. Likewise, current flows from B+ through the second and third series connected sets of parallel resistors 96A to 96C and 98A to 98C, with the same potential appearing at the junction points therebetween. With the same potential source used for both such circuit portions, and the resistance values noted hereinbefore, in the initial illuminated condition of the phototubes 8G, 82, 84, the junction points in the second circuit portion are maintained at a slightly higher potential than the phototube junction points, since a proportionally greater voltage drop occurs across the third set of parallel resistors 98A to 98C with such current flow due to the higher value of such resistances, thereby charging the condensers to the potential difference prevailing between the respective junction points, which potential difference is less than the supply voltage B+. When the first reference mark R intercepts the light illuminating the phototubes '80, 82, 84, the effective resistance of two and usually all three phototubes increasesy from the initial value to a markedly higher value, illustratively 1 megohm. With an increase in resistance of any phototube, a proportionally greater voltage drop occurs across the phototube effective resistance as compared with the voltage drop across the resistance 92A to 92C in series with the phototube, causing a drop in potential at the junction point therebetween and effectively clamping the left-hand terminal of the affected condensers 94A to 94C substantially to ground potenti-al, so that the potential at the second circuit junction points 99A to 99C is reduced to the charge then existing on the affected condensers. The affected condensers will then draw current from the second B+ potential source to charge the condensers toward the potential B+ and hence will return the voltages at the second circuit portion junction points 99A to 99C connected to the affected condensers to the voltage previously thereon, producing in effect a negative pulse at the junction points.

In order to produce an output signal responsive to darkening of at least two phototubes, the circuit is arranged including diodes 106A to 106C and diodes 108A to 108C to block the transfer of any signal through to the output terminal 113 unless at least two of the condensers 94A to 94C are affected by change in illumination on the associated phototubes. Thus if only one phototube 80 is darkened due to the passing of an opague spot rather than a line, the left-hand terminal of the affected condensers 94A will drop to substantially ground potential thus tending to drop via the diode 168A the potential at the point 104A. But with the other phototube 82 still illuminated, and the associated condensers 94B being maintained at the prevailing higher voltage, the point 104A will be maintained at that higher voltage via the conducting cross connection diode 106C. In a like manner with a reduction in illumination of any one but not two of the phototubes, the points 104A to 104C will be held at the high potential prevailing at the second circuit junction points 99A to 99C.

In the event, however, that -two of the phototubes 8G and 82 are darkened due to the passing of a line, then the left-hand terminals of both affected condensers 94A and 94B will be clamped to substantially ground potential, and via the conducting diodes 108A and 106C, the lower potential at the second circuit junction points 99A and 99B due to the charge on these condensers will be conveyed to drop the potential at the point 104A.

Such a drop in potential at any one of the points 104:1 to

104C has the effect of rendering the associated diode 110A to 110C conductive to by-pass current from the source B+ and the resistor 102 and away from the -high impedance output relay 8S thus, in effect, producing a negative pulse which is transferred from the output terminal 113 to the relay 88. Bypassing current from the relay 88 will have the effect of deenergizing the relay 88, causing it to close its contacts 90 producing an S mark signal. It will be noted that a higher impedance output device herein shown as a relay 88 is employed to insure that the potential at the point 113 is higher than the substantially ground potential pulse transferred through from the junction points 109A to 109C when two of the phototubes are darkened due to passing of a line thereby rendering the diodes 110A to 110C conductive to cause by-pass current to flow.

In this manner the S mark detec-tor phototube circuit responds to an S mark in the form of a crayon line on the glass which produces a change in excitation of at least two of the three phototubes 80, 82, 84 in the circuit, but is not responsive to an opaque mark or spot producing a change in excitation of only one phototube.

(2) Signal Storage Network The details of a preferred circuit for the signal storage block of the FIG. 5 block diagram, appear in the schematic diagram of FIG. 6. Referring to this latter figure, therefore, for the following more detailed description of this storage network, the network is energized by sources of DC operating potential conventionally shown as B+ which are connected into the network by suitable switches (not shown) when a Z length of glass moves into the inspection zone of the S mark detector before reaching the S cutter.

In general, to carry out this invention, the signal storage network includes two circuit portions to which incoming S mark detector signals, representing S marks on the Z length of glass moving past the detection, are alternately conveyed, and from which t-he same S mark signals are alternately read out and `transferred through the S mark detector stepping switch to the S relays of the S cutter.

More in detail, S mark signals are transferred alternately to the circuit portions, and such circuit portions are alternately read out and erased, by switch 120 having three sets of contacts 120-1, 120-2, 120-3, and operated by a solenoid 120-SOL. T-he latter solenoid in turn is operated by a stepping switch SS, which may be a second level of the S mark detector switch, operating in synchronism with the glass movement. Only alternate, herein shown as the even numbered, contacts of such stepping switch are used and these contacts S-R, S-2, S-4, etc., are connected to the solenoid 120-SOL. With this arrangement, with the stepping switch SS wiper arm on its odd numbered contacts, the solenoid is deenergized moving the switch arm 120A `to 120C to the position shown in FIG. 6, and with the wiper arm on its even numbered contacts the solenoid 120-SOL is energized to move the switch arms 120A to 120C to their other positions.

In the operation of the signal storage network, an incoming signal representing the first reference mark R on the glass Z length caused by the S mark detector relay 88 closing its contacts 90-1, is transferred through the switch arm 120B and 122A to a holding relay 124. The latter relay closes one set of contacts 124-1 'to seal in the relay, a second set of contacts 124-2 to connect the output ter minal of the clock in circuit with t-he clock output relay 126, and a third set of contacts to energize a reset generator 12S for resetting the clock stages to their reference state. The clock, in the present case, produces an output pulse for each 11/2" of movement of glass past the S mark detector, which pulse is used lto step t-he stepping switch wiper arm 72 from position to position synchronized with the glass movement. Thus the first clock pulse received after the clock is reset to its reference state steps the wiper 72 to the contacts labelled R. Each clock output pulse automatically resets the clock by means of the reset generator 128, so that the clock output pulses remain in step with the glass movement. The subsequent clock pulse steps the wiper to the contacts labelled S-l, S-2 and so on.

Referring again to the incoming reference mark signal, such is also conveyed through the switch arm 122A to a signal relay 130 which shifts the switch arm 122A to its upper position thereby connecting the relay 130 to a potential source B+ through the erase contacts 132-1, and sealing in the relay 130. When the stepping switch SS is shifted to the R position in unison with the S mark detector stepping switch, the solenoid -SOL is energized shifting the switch arm 120C to its read out position. With the signal relay energized and holding the reference mark signal, a pulse is transferred from the potential source B-ithrough the erase contacts 132-1, the raised switch arm 122A to a read out relay 134. The latter closes its contacts 134-1 in the circuit to the wiper arm 72 of the stepper switch thereby sending a pulse over conductor R to energize the reference relay of the S cutter relays.

With the solenoid 120-SOL so energized, an incoming S mark detector signal representing an S mark at the first S position, is conveyed to the other signal relay 136 which holds the `signal until read out when the switch 120C returns to the position shown in FIG. 5 upon deenergization of the actuating solenoid 120-SOL at position S-l of the stepping switch SS.

The erase relays 132 and 140 are energized to drop out the signal holding relays 130 and 136, respectively, opening erase relay contacts 132-1, 140-1. Illustratively, with the network in the condition shown in FIG. 6, when the first clock pulse is emitted, which shifts the signal storage network to read out the R signal, the clock pulse momentarily energizes a second relay 142 which is effective to close one set of contacts 142-1 energizing the stepping switch rotor 144, and to close a second set of contacts 142-2 in a circuit including the erase coils 132, 140. Closing the latter contacts 142-2 momentarily energizes the erase coil 140, with the circuit in the condition shown, to release the associated signal holding coil 136. With switch arm 120A in its raised position, an erase signal is conveyed in a similar manner to the erase coil 132 to release the signal holding coil 130 after read out.

(3) Clock With the S marks on the glass lengths in multiples of 11/2" Spacings, each of a series of signals produced by the S mark detector is fed via an individual channel to the S cutter scorer solenoid 1-SOL to 63-SOL at the S location corresponding to the position of the signal along a time base determined by the speed of glass movement. This is achieved in the present case by the S mark detector stepping switch and the clock which generates synchronizing signals or pulses to move the stepping switch from position to position in synchronism with the glass movement. As hereinbefore described, each S mark of a series on a glass length is detected, producing a signal which is automatically transferred through the stepping switch to the proper relay ofthe S cutter.

With particular reference to FlGS. 6, 7 and l2, the clock function may be served by various known circuits. By way of example, the clock is here shown in FIG. 7 to comprise series connected bistable multivibrators, conventionally shown as flip-flop devices. The clock has ten of such bistable means to 16S forming ten stages with the output terminal of the tenth stage being connected to a monostable multivibrator, shown as a one-shot 172 which, upon receipt of a pulse from the tenth clock stage, fires the output relay 126 and transmits a pulse to the reset generator 128 connected to the reset terminals of each clock stage.

With all ten stages of the clock set to the same reference state, one output pulse is transmitted from the tenth stage after the receipt of 1024 input pulses. The clock thus includes ten stages representing successive places of the input pulse binary number as successive powers of 2.

Still referring to FIG. 7, the clock is driven in the present case by a continuous square wave input signal of a fixed frequency. A source of such an input signal may be a tachometer generator driven in synchronism with a side line conveyor i0 as by a drive connection to the conveyor motor. The tachometer generator output is connected through suitable means for squaring and amplifying the generator pulses, herein shown as an amplifier, to the first stage of the clock.

One of the features of the present invention is the provision of means to adjust the frequency of emission of synchronizing pulses produced by the clock with a high degree of accuracy, thereby accommodating very slight variations in speed of glass movement.

To adjust the frequency of the synchronizing pulses or signals supplied by the clock, means is included in the reset circuit for selectively setting each clock stage to an initial 0 or 1 state thereby to set the reference state of all stages of the clock to the binary representation of any decimal number from one to 1024.

In the present case, and by Way of illustrating this invention, it is desired to set the clock to produce one output pulse per inch and one-half of glass movement into the cutting berth. It will be readily appreciated that for a given glass conveyor line speed, over short periods of time the speed of glass movement is uniform, but over extended time periods the glass speed may vary slightly due to bearing wear or change in size of conveyor rollers or from other factors. Moreover, glass line speed may be adjusted to a completely different speed, much higher or lower, for production purposes. The clock is adjustable, in keeping with this invention, to synchronize the S mark stepping switch with the glass movement over a wide range of conveyor speeds.

For illustrative purposes, the frequency of input signals to the clock from the tachometer is 5400 per second; an illustrative glass speed is 15" per second which is equal to the total distance of ten S marks spaced ll/z" apart-540 input pulses are, therefore, received by the clock for 11/2," of glass movement,

The selective resetting means for each clock stage enables selecting either state of each clock stage as the reference state thereby providing means to reset the entire clock to an initial state representing the complement, in binary, of a desired number of input pulses per output pulses, complementary number being 1024. Where it is desired, therefore, to produce an output pulse for every 540 input pulses; that is, an output pulse for each 11/2f' of glass movement, the clock will be reset to the reference state representing, in binary, the number 484 (l024-540=484). To this end each clock flip-hop stage has two reset terminals 0 and 1 to which the reset signal may be selectively conveyed by a selector switch 176 to 194. With the selector switch in position 0, the flip-flop is set by the reset generator pulse to its alternate state; with the selector switch in its l position, the iiip-flop is reset to its reference state. Referring to the chart of FIG. l2, the second horizontal line gives the initial states of all ip-iiop stages for the complement of 540; the third and sixth to ninth stages are set to their alternate states thereby all stages represent, in binary, the number 484. With the clock reset to the state representing the number 484, the first input pulse shifts the clock to the state representing the number 485, and so on until the clock reaches the state representing 1024 when an output synchronizing and resetting pulse is emitted from the clock tenth stage.

It will be readily understood that the resetting means herein described enables the selection of a clock output frequency between the limits of one to 1024 input pulses per output pulse. Moreover, in the present illustrative case where approximately one output pulse is required per 540 input pulses, the resetting selection provides a line adjustment of the synchronizing frequency in the order of one part in 500.

l. claim:

f ting berth for reading cutting information recorded as a series of marks on a glass sheet as the latter moves into said cutting berth from said conveyor, and means responsive to said cutting information for selectively operating certain of said glasscutting scoring and snapping means in said cutting berth corresponding to the series of marks on the sheet `to cut the glass sheet received in the cutting berth at cutting points determined by the marks on the sheet.

, 2. In apparatus for partitioning glass including a glass conveyor for moving individual glass sheets to a cutting berth, said glass sheets having a series of marks according to a record scale with the presence or absence of a mark at a point on said record scale denoting whether a cut is to be made at a corresponding cutting point on a cutting scale, the combination comprising, glasscutting means in said cutting berth including selectively operable means for scoring and snapping a glass sheet according to said cutting scale, and means immediately ahead of said cutting berth for reading cutting information recorded at said record scale, for changing said information to said cutting scale and for setting up said glasscutting means to cut said sheets at said cutting scale responsive to marks on the sheet.

3. In apparatus for partitioning individual glass sheets including a glass conveyor for moving said glass sheets to a cutting berth, and means for recording on a record medium the locations of cutting points for each glass sheet in the form of marks at one or more of each of a set of data points, the combination comprising, a cutting berth having a set of incrementally spaced glasscutting scoring and snapping means corresponding to the set of data points, means for reading the record of a glass sheet upon said sheet reaching said cutting berth including detection means operative in cooperation with relatively moving recordrmedium for detecting the presence or absence of a moving mark at each of said data points and for producing an output signal representing each cutting location mark, and means operated by said detection means output signals for selectively setting up the corresponding ones of said glasscutting and snapping means to cut said sheet at cutting points determined by marks on said record medium.

4. In apparatus for partitioning glass including a glass conveyor for moving individual glass sheets to a cutting berth, each of said glass sheets having a series of Cutting marks at spaced data points, with the presence or absence of a mark at a data point denoting whether a cut is to be made at a corresponding cutting point on the sheet, the combination comprising, detection means immediately ahead of said cutting berth for producing a signal denoting the presence or absence of a cutting mark at each data point on a glass sheet moving past said detectlon means into said cutting berth, glasscutting apparatus 1n said cutting berth including selectively operable means for scoring and snapping a glass sheet at cutting points corresponding to all said data points, and means for conveymg data point signals to said glasscutting apparatus for scoring a glass sheet at cutting points determined by cutting marks on the sheet followed by snapping the sheet at such score lines.

5. In apparatus for partitioning individual glass sheets into strips of preselected widths, each width comprising a multiple of a fixed dimensional increment, including a glass conveyor for moving said glass sheets to a cutting berth, and means operative before each glass sheet reaches said cutting berth to record on a record medium the locations of cutting points for the respective sheets in the form of bits of data at a series of data points corresponding to said cutting points, the presence or absence of bits of data at a data point determining Whether or not a cut is t be made at the corresponding cutting point, the combination comprising, glasscutting means in said cutting berth selectively operable to cut a glass sheet transversely at any one or more of multiple cutting points spaced by said fixed dimensional increment so as to provide said preselected Widths, means for reading the record of a glass sheet upon said Sheet reaching said cutting berth including detection means for producing a signal denoting either the presence or absence of bits of data at each data point for said glass sheet, and means operated by said detection means signals for setting up said glasscutting means to cut said sheet at cutting points determined by data points on said record having bits of data.

6. A glass partitioning apparatus according to claim 5 in which the glass is the record medium, which includes means for applying a series of marks to the glass sheets designating the locations of cutting points for the respective sheets, and which include means for starting said detector responsive to the passing of the first of a Series of said marks.

7. In apparatus for partitioning individual glass sheets into strips of preselected widths, each width comprising a multiple of a fixed dimensional increment, including a glass conveyor for moving said glass sheets to a cutting berth, and means operative before each glass sheet reaches said cutting berth to record the locations of cutting points for the respective sheet in the form of bits of data at a series of data points on said glass sheet spaced at a smaller distance than said fixed increment and corresponding to said cutting points, the presence or absence of bits of data at a data point determining whether or not a cut is to be made at the corresponding cutting point, the combination comprising, glasscutting means in said cutting berth selectively operable to cut a glass sheet transversely at any one or more of multiple cutting points uniformly spaced by said fixed dimensional increment so as to provide said preselected Widths, means for scanning a glass sheet moving into said cutting berth including detection means for producing a signal denoting either the presence or absence of bits of data at each data point for said glass sheet, and means timed responsive to the movement of the glass sheet and operated by said detection means signals for setting up said glasscutting means to cut said sheet at cutting points determined by data points on said sheet.

8. In apparatus for partitioning glass including a glass conveyor for moving individual glass sheets to a cutting berth, and means upstream of the cutting berth for recording a series of cutting marks at spaced data points on a record medium with the presence or absence of a mark at a data point denoting whether a cutis to be made at a corresponding cutting point on the sheet, the combination comprising, detection means operative in cooperation with said record medium for producing a signal denoting the presence or absence of a cutting mark at each data point for a glass sheet moving into said cutting berth,

, glasscutting apparatus in said cutting berth including selectively operable means for scoring and snapping a glass sheet at cutting points corresponding to all said data points, and means for conveying data point signals to said glasscutting apparatus for scoring a glass sheet at cutting points determined by cutting marks on the record medium followed by snapping the sheet at such score lines.

9. In apparatus for partitioning glass including a glass conveyor for moving individual glass sheets to a cutting berth, and means upstream of said cutting berth for recording cutting information on each glass sheet in the form of marks representing the locations of cutting points, the combination comprising, glasscutting means in said cutting berth including a set of parallel, intermittently spaced, simultaneously operable cutting elements, and a light responsive detector means for detecting cutting marks on each sheet, for setting up selected ones of said cutting elements as a sheet moves into said cutting berth, and for simultaneously operating set-up elements after a sheet is received in said cutting berth to cut up the sheet according to a cutting pattern established by said marks.

itl. In apparatus for partitioning glass including a glass conveyor tor moving individual glass sheets to a cutting berth, and means upstream of said cutting berth for recording cutting information on each glass sheet in the form of marks, the locations of cutting points for the sheet, the combination comprising, glasscutting means in said cutting berth, and a light responsive detector for detecting cutting marks on each sheet, for translating into cutting instructions the relationship of said cutting marks independently of their actual position on the sheet, and for controlling the cutting pattern of said glasscutting means for each sheet received in the cutting berth according to said instructions.

11. An apparatus according to claim 10 in which said detector is light responsive, actuated responsive to a series of marks on each glass sheet, and effective to set up a corresponding series of cutting elements in said glasscutting means of said cutting berth.

References Cited UNITED STATES PATENTS 3,141,589 7/1964 Jochim 22S-96.5

I AMES M. MEISTER, Primary Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3141589 *May 31, 1960Jul 21, 1964Saint GobainMethod of and apparatus for cutting glass sheets
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3592370 *Nov 6, 1969Jul 13, 1971Pilkington Brothers LtdCutting of glass sheets
US6616025 *Aug 31, 2000Sep 9, 2003Corning IncorporatedAutomated flat glass separator
US7234620Sep 8, 2003Jun 26, 2007Corning IncorporatedAutomated flat glass separator
US7963200 *Nov 5, 2008Jun 21, 2011Schott AgMethod for cutting off glass panes from a continuously produced glass sheet
US7975581 *Jan 22, 2009Jul 12, 2011Schott AgApparatus for cutting off glass panes from a continuously produced glass sheet
US8785812May 27, 2005Jul 22, 2014Tel Solar AgTable for receiving a workpiece and method for processing a workpiece on such table
EP2216276A2 *May 27, 2005Aug 11, 2010Oerlikon Solar IP AG, TrübbachApparatus to work out and to position a material, and associated method
Classifications
U.S. Classification225/96, 225/103
International ClassificationC03B33/037, C03B33/00, B23D36/00, C03B33/027, C03B33/10
Cooperative ClassificationC03B33/0235, B23D36/0066, C03B33/027, C03B33/037, C03B33/10
European ClassificationC03B33/10, B23D36/00B13C2, C03B33/037, C03B33/023B, C03B33/027