US3274390A

US3274390A - Glass cutting control apparatus

Info

Publication number: US3274390A
Application number: US125329A
Authority: US
Inventors: Forrest K Umbel
Original assignee: Pittsburgh Plate Glass Co
Current assignee: PPG Industries Inc
Priority date: 1961-06-16
Filing date: 1961-06-16
Publication date: 1966-09-20
Anticipated expiration: 1983-09-20
Also published as: BE619014A

Description

Sept. 20, 1966 F. K. UMBEL GLASS CUTTING CONTROL APPARATUS 8 Sheets-Sheet 1 Filed June 16, 1961 INVENTOR. Mfr MMU,

MMM/M Jill/www.

Sept. 20, 1966 F, K` UMBEL 3,274,390

GLASS CUTTING CONTROL APPARATUS Filed June 16, 1961 8 Sheets-Sheet 2 "5 ZY/fra? Aww/P4705 NVENTOR. /K Mid,

r EA j I E Sept. 20, 1966 F. K. UMBEL 3,274,390

GLASS CUTTING CONTROL APFARATUS Filed June 16, 1961 8 Sheets-Sheet 5 IN VEN TOR.

Sept. 20, 1966 F. K. UMBEL 3,274,390

GLASS CUTTING CONTROL APPARATUS Filed June 16, 1961 8 Sheets-Sheet 4 wm/ Y 5mm 5 f/T//P d MMM /fa/w qw.

Sept 20, 1966 F. K. UMBEL GLASS CUTTING CONTROL APPARATUS 8 Sheets-Sheet 5 Filed June 16, 1961 Sept. 20, 1966 F. K. UMBEI.

GLASS CUTTING CONTROL APPARATUS 8 Sheets-Sheet 6 Filed June 16, 1961 Sept. 20, 1966 F. K. UMBEI.

GLASS CUTTING CONTROL APPARATUS 8 Sheets-Sheet 7 Filed June 16, 1961 mHHmm/ f M f w fh M Sept. 20, 1966 F. K. UMBEL GLASS CUTTING CONTROL APPARATUS 8 Sheets-Sheet 8 Filed June 16, 1961 INVENTOR.

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United States Patent O 3,274,390 GLASS CUTTING CONTRGL APPARATUS Forrest K. Umbel, Verona, Pa., assigner to Pittsburgh Plate Glass Company, Allegheny County, Pa., a corporation of Pennsylvania Filed ,lune I6, 1961, Ser. No. 125,329 7 Claims. (Cl. Z50-219) This invention relates to control apparatus for directing the cutting of glass sheet or continuous glass ribbon into a number of smaller pieces.

yIn 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 8, 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 excludingy 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 nal 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 ypace with the continuous glass production.

An-other 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 ow of glass along a conveyor and laterally on side line conveyors to the S cutter apparatus;

`FIGURE 2 is a diagrammatic perspective view of the S cutter apparatus;

FIGURE 3 is a partial elevational view of the S marker apparatus;

FIGURE 4 is a sectional view taken along the lines of 4 4 of FIG. 3;

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

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

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

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

FIGURE 9 is a `partial elevational View with parts in section showing details of the S cutter apparatus;

FIGURE 10 is a side View of fFIG. 9 with parts in section;

FIGURE l1 is a schematic Wiring diagram of the S cutter control circuit; and

Patented Sept. 20, 1966 FIGURE 12 is a chart illustrating different states of the clock stages.

While the Iinvention 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 dened by the appended claims.

General organization Upon more specific reference to the drawings it will be seen that the invention is applied to apparatus employed in the rmanufacture 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 1, 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 to left in FIGURE 1) by means of a roller conveyor past inspection stations to a glass cutting apparatus for making successive transverse cuts across the Iglass 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 cuts7 are made to sli-t or slice the Z lengths iinto smaller usable widths In the copending application, Serial No. 850,360, tiled Nov. 2, 1959, 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 FIGURE l, in view of a programmed series of sizes. In carrying out this partitioning process, a secondary record is made of the locations of defects appearing in the glass. Z and S cut decisions are made in the computer based on defect location information Vderived from the secondary record The Z cutter is operated upon command of the computer responsive to such decisions. Still referring to FIGURE 1, 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 lengths has on its surface a record of the cuts required to complete the partitioning process, in the for-m 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 Serial No. 850,460, now Patent No. 3,191,857, of 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 rst manually inspected for the presence of defects, or, alternatively, the glass may be optically inspected at inspection stations upstream of the Z cutter. With manual inspection, those defects of ,such severity as to affect the quality of the glass are dimensionaily located by marks placed -on lthe glass. Such defect marks Iare detected by photosensitive devices mounted over the glass line and dimensional information as to such defect marks is transferred from the detectors to defect storage apparatus for making a secondary record of defect location. While the present invention is not limited to the particular defect detect-ion, 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 cert-ain 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' Follow-ing 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 Iis operated upon command by the computer to make the successive Z cuts. In order to make the longitudinal S cuts on which the calculations depended for choosing the Z by S sizes and the Z lengths, Without interfering with the flow 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 Serial 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 diagrammatically in FIGURE 1, the S marker apparatus is carried on a fixed bridge 10 over the conveyor Iand is connected by cable to the computer for transfer of the command signals. In this partitioning process the glass is cut in both the Z and S directions to dimensions which are integral multiples of 2". Where the glass on the line is 128l in width, in the present illustr-ative case, the bridge 10 carries siXty-th-ree individually operable markers 12 for placing marks on the glass dening 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 ma-de, 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 desire-d, 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 S markers, including the R and sixty-fourth reference markers, are mounted on 11/2" centers so that the spacing between S marks on a 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 12 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 modifications.

Referring to FIG. 4, each S marker includes a crayon 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 toward the marking position by a spring 1S. The position of each holder may lbe adjusted to move the crayon toward the glass marking position by a cam 2t) once the solenoid l22 has operated the latch 16 to release the holder. Individual cams 2li are provided for each holder and are rotated through successive positions of a cycle by a hydraulic means 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 connection .to the solenoid associated with the marker at that S loc-ation.

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. Huffman, George W. Misson, and William F Galley, 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 ont'o the table 30 where the glass sheet is clamped for the usual scoring and snapping glass cutting operations. A carriage 37 movable transversely of the table and glass Z length carried 4thereon from a home position shown in FIG. 2 to an .away position at the opposite side of the table carries siXtyJiive individual scoring devices SS-R to 38-64 mounted on 2 Icenters the full 'length of the carriage. IEach .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 Iand a full set of score lines is made during travel of the carriage between its home and 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 sc-oring Wheel 42 pivotally mounted by a lever `44 which is normally held by a latch 46 above the glass. Actuation of the associated solenoid RSOL to 64SOL raises the latch 46 allowing a spring 48 to pivot the lever 44 and lower the scoring wheel 42 into glass contact. The solenoids RSOL to 64SOL are selectively actuated by control means hereinafter described 'in detail.

Below t-he 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 Sil-R to Sti-64. Each snapping device 5t) has a snapping head or caster 52 which m-ay be raised into glass contact. To this end each snapping device also has a hydraulic cylinder 54 operated by a solenoid valve RSV to 648V, the hydraulic -cylinder being connected to r-aise 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 carri-age 3l) carrie-s resilient fulcrum elements 58 which are positioned between each of the scoring devices 50.

Accordingly, a program of S scorer solenoids RSOL to 63SO'L 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 lall S cuts by driving the carriage, by `means of ia hydraulic motor, across the glass with all scoring devices of the S cut program or series in glass contact to p-roduce all the score line-s. The carriage is dr-iven to its away position wherein the sco-rers lare located past the edge of the glass sheet as shown in FIG. 10, and with the carriage in said position the snapping devices 50 are successively -operated to snap the glass sheet at each score line starting wit-h the rst snapping device 54)R adjacent the left side of FIG. 2 tand the following conveyor section 36, and continuing with each successive snapping device until all score lines have been snapped. As each snapping device is hydraulica'lly 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. Where 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 fulcrum devices breaks the glass, starting the cut which runs across the sheet following the `sco-re line. After the scoring Iand sn-apping 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 of a succeeding Z length of glass.

Reference is also made to FIG. 11, a schematic diagram of the S cutter cont-rol circuit. The scorer solenoids RSOL to 64SOL are shown at the right side of the diagram connected between 115 volt A.C. buses 70 in series with relay contacts RCR to 64CR. The buses 70 are energized from a 115 volt A.C. source through switches, not shown, which are closed by a glass Z length moving into the S lcutter and are opened following the cutting operation. The scorer solenoids are energized when S relays RCR to `64CR are actuated either -manual-ly to insert a program of S outs, by means of push button switches RPB to 64PB, 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 t-hrough the wiper 72 of the stepping switch to the appropriately numbered S relay RCR to 64CR to set up the scorer devices.

When an S relay RCR to 64CR is energized by one of the push buttons RPB to 64PB or through the stepping switch, holding contacts 74-R to 74-64 are closed to seal in the relay coil. The scorer solenoid RSOL to 64SOL thereby remains energized after the wiper 72 passes the same numbered contact. Alfter 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 score-r devices is -driven across the table to score the glass sheet. When the carriage 4reaches its away position, it is stopped and a snapping device stepping -switch at the lower part of FIG. l1 is actuated to operate the snapping devices Sil-R to 50-64 in sequence. Thus the switch 75 is closed by suitable Imechanism .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. lTo 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, signal-s from the S mark detector Iare conveyed through a signal storage network and .an S mark detector stepping switch to the S relays of the cutter apparatus. lln keeping with this invention, the clock drives the stepping switch in synchronism with a Z length of glass passing the S mark detector. The rst 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. yIt will be recalled that the S marker reco-rds 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 l-/z", to the requisite 2" cutting sca-le. 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 lS-l position, and 4so on, always lagging one step behind the `glass movement. The S-1, S-2, S-3, etc., contacts of the stepping switch are connected to operate the l-C'R, Z-CR, S-CR, etc., relays o-f the S cutter, respectively, to operate the same numbered scorer solenoids lSOL, ZSOL, SSOL, 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 store-d in the signal storage network to avoid missing or misplacing S mark signal-s between .contact positions of the wiper 72, and this signal is read out of the signal storage 4network 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 gl-ass sheet at that S location when the carriage 37 of the S cutter is operated. A series of scorer solenoids 1SOL to 63SOL Vis thus set up to carry out the S cut decisions recorded as S marks Ion 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 Ian S mark detector adjacent the same marginal edge relative to glass movement, above either 4right 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.

1. Mrz/'k Detectan- 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 11/2l 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 'phototu-bes.

vand are closely spaced in alignment transversely of the v 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 interceptsthe light from below the glass illuminating allthreephototubes producing, under such conditions,.a reductionin illumination of all three To discriminate between an S mark line andan opaque ordark spot'on the` glass, an S mark will be represented by dark signalssimultaneously at any two of the three phototubes in thecircuit, and will produce an output signal, vwhile a dark signal at only one phototube produces no output signal.

Also referring to FIGURE'l, the first mark R on a glass sheetmoving along. a side line conveyor is a reference-mark and representsthe marginal cut to be made; other marks define the S cut locations in terms of the 2 vdimensional unit; that is, S-17 represents 34 and S-35 represents 70 from the referencemark. Such S marks are shown for purposes of illustration, crowded into a band ofrnarks on the glass wherein the marks appear at multiples of 11/2 spacings, and thus such marks are notat the actual locations of the'S cuts to be made. With this arrangement to gain time in the S direction, all S t cut4 information'may be read from the glass sheet to set up the Srcutter apparatus before the sheet is completely into the cuttingfberth. It will be understood that the S marks herein shown as lines may be any opaque line or ating potential conventionally shown as B+, and normally illuminated through a glass sheet by the light 86 below the conveyor. Theresistance of such a phototube increases, representing .a dark signal, responsive to a reduction in illumination of the phototube. The three phototubes80,ff82,84 are each connected in a first circuit position in? series with` a resistor 92A to` 92C, providing a firstset 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 photo- .tubesv80, 82,-84-and theresistors92A to 92C with the phototubes uniformly illuminated and such junction points are connected throughcondensers 94A to 94C to a second circuit portionincluding second and third sets of parallel resistorsV 96A to 96C, 98A to 98C, respectively, connected in series between a'source ofD.C. potential B+ which may be. the same; potential source energizing both circuits, and ground. vFor 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 resistorsr 98A to 98C of the third set `are also arranged in series with a resistance 102 illustratively of about 2 megohms anda source of D.C. potential shown as B+ to operate a suitable signalling device, herein shown as a relayv88 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 104C 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 86 is falling on all three phototubes, current flows from B+ through each

phototube

80, 82, 84 and the first set of resistors 92A to 92C causing the same potential to appear at the junction points therebetween and the left hand terminals of all three condensers 94A to 94C. Likewise, current ows 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 thejunction 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 Si), 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 increases from the initial value to a markedly higher value, illustratively l 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 potential, 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 pointsf99A 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 thecondensers 94A to 94C are affected by change in illumination on the associated phototubes. Thus if only one phototube is darkened due to the passing of an opaque 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 198A the potential at the point 104A. But with the `other phototube 82 still illuminated, and the associated condensers 94B `being maintainedat the prevailing higher voltage, the point 104A will be maintained at that higher vol-tage via the conducting cross connection diode 106C. Ina 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 points99A to In the event, however, that two of the phototubes80 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 junctionpoints 99A land 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 104A to 104C has the effect of rendering the associated diode 110A to 110C conductive to bypass current from the source B+ and the resistor 102 and away from the high impedance output relay 88 thus, in effect, producing a negative pulse which is transferred from the output terminal 113 to the relay 88. Bypassing current from the the glass movement.

9 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 bypass current to flow.

In this manner the S mark detector 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. 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 D.C. operating potential conventionally shown as B+, which are connected into the v 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 0f glass moving past the detection, are alternately conveyed, and from which the 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 a switch 120 having three sets of contacts 1Z0-1, 1241-2, 12h-3 and operated by a solenoid 12tlSOL. The 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, 8 4, etc., are connected to the solenoid 120SOL. With this arrangement, with the stepping switch SS wiper arm on its odd numbered contacts, the solenoid is deenergizcd 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 120SOL 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, 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 terminal of the clock in circuit with the clock output relay 126, and a third set of contacts to energize a reset generator 128 for resetting the clock stages to their reference state. The clock, in the present case, produces an output pulse for each 1%." of movement of glass past the S mark detector, which pulse is used to step the stepping switch wiper arm 72 from position to position synchronized with Thus the iirst 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 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 potent-ial 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 SO^L is energized shifting the switch arm 120C to its read out position. With the signal relay 1.30 energized and holding the reference mark signal, a pluse is transferred from the potential source B+ through the erase contacts 132-17 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 pluse over conductor R to energize the reference relay of the S cutter relays.

With the solenoid 12080L so energized, an incoming S mark detector signal representing an S mark at the rst 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 120SOL at position S-1 of the stepping switch SS.

The erase relays 132 and 140 are energized to drop out the signal holding relays and 136, respectively, opening erase relay contacts 132-1, 1140-1. 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 166. With switch arm 120A in its raised posi-tion, an erase signal is conveyed in a similar manner to the erase coil 1i32 to release the signal holding coil 130 after read out.

3. CIOck.-With t'he 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 1SO L to 63SO=L 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 of the S cutter.

With particular reference to FIGS. 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 liip-iiop devices. The clock has ten of such bistable means to 1re-'8 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, tires the output relay 12'6 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 10 as by a drive connection to the conveyor motor. The tachometer generator output is connected through suitable means for squaring and amplifyl I ing the genera-tor 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 circuitfor selectively setting each clock stage to an initial 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 per second which is equal to the total distance of ten S marks spaced 11/2 apart-540 input pulses are, therefore, received by the clock for 11/2l 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 11/2 of glass movement, the clock will be reset to the reference state representing, in binary, the number 484 (102\4-540=484). To this end each clock flip-flop stage has two reset terminals O and 1 to which the reset signal may be-seleotively conveyed by a selector switch 175 to 194. With the selector switch in position O, the flip-flop is set by the reset generator pulse to its alternate state; with the selector switch in its l position, the flip-flop is reset to its reference state. Referring to the chart of FIG. 12, the second horizontal line gives the initial states of all nip-flop 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 rst 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 fine adjustment of the synchronizing frequency in the order of one part in 500.

I claim as my invention:

1. In apparatus for reading information from a continuously moving record where -bits of data are stored at a series of points comprising a set on said record, the combination comprising, detection means for producing a signal denoting either the presence or absence of bits of data at each data point passing said detection means, pulse generating means operated in accord with said record movement for generating a synchronizing pulse as each data point passes said detection means, a multiplicity of output channels comprising `a set of output channels corresponding, respectively, to said record data points, and means operated by said synchronizing pulses for feeding successive signals from said detection means to the respective channels coresponding to the data points.

2. In apparatus for reading information from a continuously moving record where bits of data are stored at a series of points comprising a set on said record, the combination comprising, detection means for producing a signal denoting either the presence or absence of bits of data lat each data point passing said detection means, -pulse generating means operated in accord with said record movement for genera-ting a synchronizing pulse as each data point passes said detection means, a set of output channels corresponding,respectively, to said record data p-oints, means operated by said synchronizing pulses for feeding successive signals from said detection means to the respective channels corresponding to the data points, and means for adjusting the rate of emission of pulses Ifrom said pulse Agenerating `means to synchronize the latter with said record movement.

3. A system for detecting a moving line as distinguished from a moving spot, comprising three photosensitive elements mounted in alignment so that a passing line simultaneously intercepts light illuminating said elements from a light source behind said line, means responsive to a reduction in illumination of each of said elements producing a dark signal at a terminal electrically connected to the appertaining element, means connecting each one of said terminals and a different one of the other of said terminals for transferring a dark signal produced by a reduction in illumination of one photosensitive element to two of said three terminals, -and means for producing an output signal responsive to a dark signal at all three terminals representing a reduction in illumination of at least tw-o of said photosensitive elements due to a passing line.

4. In a photoelectric circuit including three photosensitive type phototubes, means for producing an output signal responsive to a simultaneous reduction in illumination of at least two of said phototubes, comprising: a set of three condensers connected to said phototubes, respectively, so `as to be maintained charged with uniform illumination of said phototubes; means for discharging each of said condensers responsive to a reduction in illumination of the connected phototube; a set of three terminals connected, respectively, to said condensers; means including isolating diodes cross connecting each `one of said terminals with ya different one of the latter so `as to drop the potential at two of said terminals responsive to the discharge of one condenser; and an output circuit for producing a signal responsive to a drop in potential `at all three terminals representating a reduction in illumination of at least two of sa-id phototubes.

5. In a photoelcctric circuit including three photosensitive type phototubes, means for producing an output signal responsive Vto a simultaneous reduction in illumination of at least two of said phototu-bes, comprising: a first circuit portion including a resistor and a source of D.C. operating potential in series with each phototube with the three resistors arranged in parallel so as to provide the same first potential at all three junction points between said phototu-bes and resistors responsive to uniform illumination of said phototubes, and a lowersecond potential at the junction point between any one of said phototubes and the series resistor responsive to reduced illumination of said one phototube; a set of three second circuit portion junction points connected to a source of D.C. operating potential; a condenser connected to each one of said rst circuit portion junction points and to one of said second circuit portion junction points; means for transferringadrop in potential from any one of said first circuit portion junction points to a different two of said second circuit portion junction points, and an output circuit for producing a signal responsive to a drop in potential iat all three of said second circuit portion junction points representing a reduction in illumination of at least two of said phototubes.

6. In a photoelectric circuit including three photosensitive type phototubes, means for producing an output signal responsive to a simultaneous reduction in illumination of at least two of said phototubes, comprising: a first -circuit portion including three rsistors and a source of D C. operating potential with one of said three resistors in series with each phototube and with the three resistors arranged in parallel so as to provide the same first potential -at all three junction points between said phototubes and resistors responsive to uniform illumination of said phototubes, land a lower second potential at the junction point @between any one of said phototubes and the series resistor responsive to reduced illumination of said one phototube; a second circuit portion including a set of three parallel resistors with each resistor `of said set in series with a resistor of another set of three parallel resistors, a source of D.C. operatin-g potential in series with said sets -of resistors to provide a third potential at all three junction points between the resistors of said sets, `said third potential being higher than said first and second potentials, a condenser connected between each one of said first circuit portion junction points and one of said second circuit portion junction points so that reduced illumination of any one of said phototubes affects one condenser yand produces a dark signal represented lby a drop in potential at the second circuit por-tion junction point connected to the affected condenser; means including isolating diodes cross conecting each one of said second circuit portion junction points with la dierent one of the latter so as to drop the potential at two of the latter junction points responsive to a single dark signal land an output circuit for producing a signal responsive to Ia drop in potential at all three second circuit portion junction points representing a reduction in illumination of at least two of said phototubes.

7. In a photoelectric circuit including three photosensitive type phototubes, means for producing an output signal responsive to a simultaneous reduction in illumination of -at least two of said phototubes, comprising: a set of three condensers having terminals connected to said phototubes, respectively, each of said terminals being connected in a c-ircuit so as to be maintained at a fixed potential with uniform illumination of said phototubes and `at a lower potential representing a dark signal responsive lto a reduction in illumination of the connected phototube; means for charging each of said condensers from a potential source upon a reduction in illumination of `the connected phototube producing a dark signal at the `condenser terminal; a second set of three terminals connected, respectively, between said condensers and said potential source; means including isolating diodes cross connecting each one of said second set of terminals with a diierent one of the latter so as to drop the potential at two of said terminals responsive to a dark signal produced by a reduction in illumination of one phototube; and an output circuit for producing a signal responsive to a drop in potential at lall three terminals representing a reduction in illumination of at least two of said phototubes.

References Cited by the Examiner UNITED STATES PATENTS 2,632,855 3/1953 Bendz 250-209 2,840,371 6/1953 Frommer. 2,674,308 4/1954 Knobel 83-365 X 2,793,471 5/ 1957 Motoharu Kurata et al 225-96.5 2,803,751 8/1957 Hechler Z50-209 2,939,963 6/1960 Rideont. 2,948,991 8/ 1960 Walters et al. 225-96.5 3,044,216 7/ 1962 Billinger 22S-96.5 3,067,646 12/ 1962 Ressen. 3,107,834 10/1963 Huiiman et tal. 22S- 96.5

FOREIGN PATENTS 1,23 6,148 6/1960 France.

WILLIAM W. DYER, JR., Primary Examiner.

RAPHAEL M. LUPO, Examiner.

I. M. MEISTER, Assistant Examiner,

Claims

2. IN APPARATUS FOR READING INFORMATION FROM A CONTINUOUSLY MOVING RECORD WHERE BITS OF DATA ARE STORED AT A SERIES OF POINTS COMPRISING A SET ON SAID RECORD, THE COMBINATION COMPRISING, DETECTION MEANS FOR PRODUCING A SIGNAL DENOTING EITHER THE PRESENCE OR ABSENCE OF BITS OF DATA AT EACH DATA POINT PASSING SAID DETECTION MEANS, PULSE GENERATING MEANS OPERATED IN ACCORD WITH SAID RECORD MOVEMENT FOR GENERATING A SYNCHRONIZING PULSE AS EACH DATA POINT PASSES SAID DETECTION MEANS, A SET OF OUTPUT CHANNELS CORRESPONDING, RESPECTIVELY, TO SAID RECORD DATA POINTS, MEANS OPERATED BY SAID SYNCHRONIZING PULSES FOR FEEDING SUCCESSIVE SIGNALS FROM SAID DETECTION MEANS TO THE RESPECTIVE CHANNELS CORRESPONDING TO THE DATA POINTS, AND MEANS FOR ADJUSTING THE RATE OF EMISSION OF PULSES FROM SAID PULSE GENERAING MEANS TO SYNCHRONIZE THE LATTER WITH SAID RECORD MOVEMENT.