US3461759A

US3461759A - Sheet inspecting and segregating apparatus

Info

Publication number: US3461759A
Application number: US647403A
Authority: US
Inventors: Harold F E Dixon; Angelo Vaccaro
Original assignee: Columbia Controls Research Corp
Current assignee: International Business Machines Corp; Columbia Controls Research Corp
Priority date: 1967-06-20
Filing date: 1967-06-20
Publication date: 1969-08-19
Anticipated expiration: 1986-08-19
Also published as: GB1185788A; DE1773661A1; FR1572689A; SE364241B

Description

' sanmmsrmc'rmo Am: saenomma APPARATUS 2 Sheets-Sheet 1` med June zo.v

` INVENTOKS Harp ab FE Dz; xon 1413@ o Vacca/7o United seres Patent o1 ace 3,461,759 Patented Aug. 19, 1969 U.S. Cl. 8.3-80 8 Claims ABSTRACT OF THE DISCLOSURE An apparatus, that inspects a continuously moving web for defects, cuts the web into sheets and then segregates the sheets having defects from the defect-free sheets in whichthe length of the sheets may be adjusted without changing the position of the inspection station or the cutting station while still maintaining correspondence between a defect sensed in the web and the sheet in which it finally appears.

In U.S. Patent No. 3,292,469, assigned to the assignee of the present application, there is disclosed an apparatus that photoelectrically inspects a moving web for defects and if it senses a defect produces an electric signal. After inspection, the web is moved to a cutting station where it is cut into a sheet with the cutting station being more than one sheet length away from the inspection station. Thereafter, each sheet is guided to either one storage compartment for sheets having defects or another storage compartment for defect-free sheets.

The signal from the inspecting station is produced when a `defect is sensed and in order to correlate the portion of the web having a defect with the sheet into which it is subsequently cut, there is a storing means which has a plurality of places with each place being responsive to a defect signal from the inspection station for the duration that the web which constitutes a sheet is beneath the sensing means. In order to relate a place with a sheet, the cutting station provides a cutting signal to the storing means which advances each place one step for each sheet length passing underneath the sensing means. While such a device has been found completely satisfactory, it will be understood that if it is desired to change the length of the sheet being cut, that the relationship between the conditioning of the storage means for receiving a defect signal must be maintained with respect to the cut sheet otherwise the existence of a defect will be stored in a wrong place and the sheet carrying the defect will not be segregated, While a sheet that does not have the defect but in which the storage means indicates a defect exists, will be segregated into a compartment for the sheets having defects.

It is accordingly an object of the present invention to provide an apparatus of the above type in which the length of the sheets may be easily varied but yet in which the correspondence between the storing means for sensed defects is maintained with the cut sheets.

Another object of the present invention is to be able to adjust the apparatus so that such correspondence may be easily, positively and effectively maintained and moreover to be able to perform the adjustment under actual operation conditions without stopping the apparatus.

In carrying out the present invention, the storing means for the retaining of the information of the existence of a defect consists of a plural stage shift register having an entrance stage which receives the information that a defect exists in the web at the time it passes the inspection station and a terminal stage that is employed to actuate the sheet segregating means. The number of stages in the shift register at least equals the number of sheets that can be cut from the web between the inspection station and the cutting station plus any stages necessary to cause actuation of the segregating means. For sequentially advancing the shift register and conditioning the entrance stage to be acceptable to defect existing information, there is provided a signal that is produced by the cutting means, with a cutting signal being produced for each sheet cut. The cutting signal to the shift register must accordingly be in correspondence with the portion of the web at the inspection station that will be the beginning of a sheet when the web is cut so that while the length of the web that will constitute this sheet passes the inspection station, the entrance stage will be in condition to receive defect existing information. When the portion of the web which will constitute the beginning of the next sheet is at the inspection station, the shift register must have received a cutting signal to be advanced so that defect existing information on the next length will be introduced into the storage means to correspond to the sheet into which the next length will be subsequently cut.

While the apparatus may be altered to change the length of web between the cutting station and the inspection station to be an exact multiple of a unit length of a sheet, in the present invention the distance therebetween is maintained constant thus obviating a change in the machinery. For providing the cutting signal at the proper time, a switch is mounted to be adjustably related to the cutting means so that a cutting signal will be produced at an instant that is variable to the instant when the web is being cut to produce a sheet. In order to align the portion of the web that will be the beginning of each sheet at the inspection station with the actual cutting of the web, there is provided a means for substantially simultaneously producing an identifiable or sensible mark on the web in alignment with the inspection station when the cutting signal is produced. When the web has moved sufficiently so that the sensible mark has approached and passed the cutting station, an operator can observe the relative positions of the mark and the beginning of a sheet and accordingly adjust the cutting signal means with respect to the knife so that the mark is moved to correspond with the knife. In this way, the correspondence between the beginning of the sheet at the inspection station and the cutting of the web will be achieved without any alteration in the structure of the apparatus and while the apparatus is running.

Other features and advantages will hereinafter appear.

In the drawing:

FIGURE l is a diagrammatic representation of the inspecting and segregating apparatus for sheet material of the present invention.

FIG. 2 is a perspective view partly in section of the switch adjusting means.

FIG. 3 is a block and schematic diagram of the electrical circuit of the present invention.

FIG. 4 is a representation of a length of the web having sensible marks thereon.

Referring to the drawing, the apparatus is generally indicated by the reference numeral 10 and is substantially identical to the apparatus disclosed in the above-mentioned patent. There is accordingly a moving web 11 of sheet material that passes over a roller 12 with illumination from a light source 13 being directed thereagainst. The light is reflected from the top surface of the web at an inspection station 14 to a photoelectric means 15 which produces a defect signal if there is a change in light reflected such as caused by a defect. The continuous web from the inspection station 14 is made to traverse a path that includes

rollers

16, 17 and 18 to a cutting means, generally indicated by the reference numeral 19.

The cutting means includes a knife 20 that is mounted on a shaft 21 that is rotated by an adjustable speed drive 22. Each rotation of the shaft 21 will cause the knife to produce one cut in the web at a cutting station 19 to thereby form the web into separated sheets 23. Each sheet 23 is directed into a segregating means `24 having a defect-free sheet compartment 25 and a defect-containing sheet compartment 26. For directing the sheets into one or the other of the compartments, a pivotally operated finger 27 is provided that functions in a manner disclosed in the above-noted patent. Further contained on the shaft 21 to be driven thereby is an angularly adjustable switch 28 that provides a cutting signal and a segregating switch 29 which produces a signal for the segregating means 24.

`In addition to the above structure, there is mounted adjacent the inspection station 14, a solenoid 30 having an arm 31 that carries a means for producing a sensible mark, such as an ink pad 32, if an ink mark is desired. Normally the ink pad 32 is maintained away from the web in any convenient manner but upon energization of the solenoid it will be forced against the web to provide an ink mark that is located in alignment with the inspection station 14.

`Referring to FIG. 2, the angularly adjustable switch 28 that produces the cutting signal includes a container 33 into which projects a continuation 21a of the shaft 21. From the other side of the container there projects a rod 34 to which is fastened a knob 35 with the latter being positioned on the exterior of the container for manual manipulation. While the switch 28 may take the form of a snap action switch arcuately positionable about a cam, or a photocell and relatively positionable light source, in the embodiment shown herein, the other end of the rod in the container supports a proximity switch 36 while the end of the shaft 21a has an eccentric 37 secured thereon that carries a proximity switch actuator 38. The actuator 38 and the proximity switch may be of any well known construction as for example the proximity switch being sensitive to the presence of a paramagnetic material within a small deflection angle and the actuator 38 may be a metal pin.

In operation, as the shaft 21a rotates, the actuator 38 also rotates therewith and will cause actuation, i.e. closing, of the switch 36 when the pin is at a definite angular position with respect to the switch. By controlling the angular position of the switch by the knob 35, its actuation with respect to the shaft 21 and the cutting by the knife 20 may accordingly be adjusted and set.

Leads from the proximity switch 38 may be conveniently brought to terminals 36a mounted on the container which -may be connected to appropriate amplifiers or relays. In addition, for facilitating adjustment of the knob 35, it may be provided with indicia 39 that cooperate with an indicator 40 and to prevent complete rotation of the knob 39 it may further carry a pin 41 that is abuttable against the indicator 40. Moreover, if desired, the indicator 40 may also by means of a screw 42 serve as a clamp to clamp the knob and hence the switch in its selected position.

Shown in FIG. 3 is the electrical circuitry for the apparatus including connections between the heretofore mentioned structures. Within the dotted line 43 are the components electrically connected in a manner disclosed in the above-noted patent. Thus there are photocells 44, amplifiers 45 and amplifier and pulse shaping circuit 46, a flip-Hop 47 and a shift register 48 having an entrance stage 48a and a terminal stage 48h. Moreover, there is provided an AND gate 49 connected to the terminal stage 48b and to the segregating switch 29 for operating a solenoid 50 that in turn pivots the segregating finger 27. The shaft 21 in addition to operating the switch 28 also operates a cam 51 which serves to control the operation of the switch 29.

The switch 28 in addition to providing a cutting signal to the ip-iiop circuit 47 and shift register through a monostable vibrator circuit 47a, is connected to control the energization of the solenoid 30I when the cutting signal is produced. The connection `between the switch 28 and the solenoid 30` includes a manually operable switch 52 for preventing the solenoid 30 from being energized each time the switch 28 closes for reasons which will 'be hereafter apparent.

The apparatus 10 functions as disclosed in the abovenoted patent so that each time the shaft 21 revolves, a sheet 23 is cut from the web and a cutting signal is passed to the flip-flop 47 and shift register 48. The latter signal causes the shift register to sequentially advance its stages and prepare the entrance stage 48a to receive information from the liiip-fiop 47 as to whether or not there has been a defect in the portion of the web that has passed the inspection station during the duration between cutting signals. After sufficient advances of a number that is equivalent to at least the number of sheets in the web between the inspection station and the cutting station, the terminal stage 48h will have information of whether or not the sheet just cut has a defect. lf it has a defect then the AND gate 49 will pass this signal and the signal from the segregating switch 29 to cause energization of the solenoid 50 and operation of the finger 27 to deflect the defect bearing sheet into the defect containing sheet compartment 26. Without information in the terminal stage of a defect, the finger 27 will not be actuated and hence the sheet will pass into the defect-free sheet compartment 25,

When it is desired to change the length of the sheets `being cut from the web, the first step is to adjust the adjustable speed drive 22 so that the shaft 21 revolves at a speed in which one revolution thereof produces the exact time for a length of the web to pass lby the cutting station that is equal to the desired length of the sheet. The knife 20 will then cut each sheet to the desired length. The varying of the speed of rotation of the knife accordingly enables the length of the sheet to be adjusted without changing the speed of the web. With the rotation of the shaft 21 set to cut the desired length of a sheet, an operator then closes switch 52 which causes the solenoid 30 to be actuated each time the switch 28 is closed. This will produce on the web, as shown diagrammatically in FIG. 4, an X mark 53 that is pictorially shown as being out of alignment with the place where the sheet will be cut. Subsequent movement of the web will continually produce the marks 53 on the web 11 and when the first mark 53a is at the cutting station 19', an operator can determine the closeness of the ends of the cut sheet with respect to the mark 53a.

If the mark 53a does not correspond with the cut in the web, the operator then adjusts the knob 35 to move the switch 36 angularly with respect to the shaft 22. As the mark 53a is closer to the cutting station than a subsequent mark 53b, the knob 35 is pivoted counterclockwise to cause the switch to ibe actuated angularly nearer to the position of the knife 20. After movement of the knob 35, it will be appreciated that the marks will be continually produced on the paper as indicated by the circles 54, that they will be the same distance apart as the X marks 53 but that the distance on the web between the mark produced before turning of the knob 35 and the mark produced after turning of the knob, i.e. between the last X and the first O, will be of a different length. In this manner an operator 'by adjusting the knob 35 will gradually cause the marks produced lby the solenoid 30 to register with the cut of the knife on the web at the cutting station. Hence the inspection station will be in register with the portion of the web which will be the beginning of a sheet.

When the marks and the cutting station are aligned, the switch 28 is operated at the same time as when the beginning of a sheet is located at the inspection station 14. The operator then opens the switch 52 to prevent further marks from being made on the web. The switch 28 as described in the above-noted patent, serves to actuate the shift register 48 to cause it to advance sequentially and to render its entrance stage 48a receptive to a signal from the photocells 44. As there is correspondence between the actual cutting of the sheet and the appearance of the beginning of a sheet under a photoelectric means 15, defects appearing at that portion of the web between two cutting signals from the switch 28 will accordingly 'be stored in the entrance lflip-fiop and subsequently sequentially advanced to cause operation of the AND gate 49.

While the embodiment of the invention herein described has been shown as being applied to a specific apparatus, it will be understood that the invention is usable with other and different `sheet inspecting and segregating apparatus. Moreover, it is contemplated that sensible marks other than ink spots, such as notches, slits, electric discharge, etc., may be employed if desired.

It will accordingly be appreciated that there has been disclosed a sheet inspecting and segregating apparatus which inspects a continuous web, subsequently cuts the web into sheets and segregates the defect-free sheets from the defect-containing sheets. The apparatus has fixed inspection and cutting stations which are located an extent of the web away from each other greater than the length of a sheet. By the present invention, the apparatus is capable of being adjusted for different length sheets without moving the stations while still maintaining correspondence between the beginning of a sheet at both stations. This is achieved by the use of an adjustable switch means that is capable of varying the duration between the time the sheet is cut and the time the cutting signal is produced. To enable the attaining of the proper adjustment, marks are -made on the web and when the cutting and the marks coincide, the apparatus is properly adjusted.

Variations and modifications may be made 'within the scope of the claims and portions of the improvements may be used without others.

We claim:

1. In combination with a sheet inspecting and segregating apparatus for forming sheets from a continuous web having means for moving the web, inspecting means extending transversely of the web at an inspection station for sensing defects and providing a defect sensed signal, cutting means for cutting the web into sheets at a cutting station, said cutting station being located a determined length of the web from the inspection station with the length being greater than the length of one sheet, storing means for receiving the defect sensed signal and individually storing and sequentially advancing the signal as the defect moves in the web from hte inspection station to the cutting station, said storing means being advanced and rendered receptive to a defect signal by a cutting signal producing means each time a sheet is cut, the improvement comprising operable means for marking the web at the inspection station when the cutting signal is produced and means for adjusting the relationship of the appearance of the cutting signal with respect to the cutting of the web into a sheet to provide correspondence between the mark on the web and the -beginning of a sheet to enable the cutting signal to the storing means to correspond with the beginning of each sheet appearing at the inspection station.

2. The invention as defined in claim 1 in which the cutting means includes a movable knife, means for moving the knife to a cutting position and to a non-cutting position for the duration required for a sheet-length of the web to pass the cutting station and the adjusting means is interconnected with the knife moving means.

3. The invention as defined in claim 2 in which the knife moving means includes a shaft with the knife [being at its cutting position for a predetermined position of the shaft, the cutting signal producing means includes a switch and a switch actuator and means for adjustably mounting the switch with respect to the actuator to enable said switch to be actuated at an adjustable angular position of the shaft.

4. The invention as defined in claim 3 in which the switch actuator includes a paramagnetic element secured on the shaft for rotation therewith and the switch is a paramagnetically actuated proximity switch mounted to be within the movement of the element.

5. The invention as defined in claim 4 in which the switch is mounted for pivotal movement, means for pivoting the switch including a knob and means for clamping the pivoting means in its adjusted position.

6. The invention as defined in claim 3 in which the knife moving means includes an adjustable speed drive to enable adjusting the duration of the non-cutting movement of the knife.

7. The invention as defined in claim 1 in which the operable means is interconnected with the cutting signal producing means for actuation thereby and manually operable means for preventing actuation of the operable means.

8. The invention as defined in claim 7 in which the operable means includes a solenoid having a movable armature, ink means carried by the armature and means mounting the solenoid to have the armature when energized position the ink means on the Web in alignment with the inspection station.

References Cited UNITED STATES PATENTS 2,623,587 12/1952 Hervey 83--80 X 2,950,640 8/ 1960 Camp 83-80 X 3,264,916 8/1966 Owen 83-80 3,292,469 12/ 1966 Vaccaro 83--80 3,403,782 10/ 1968 Schafer 83-80 X WILLIAM S. LAWSON, Primary Examiner U.S. Cl. X.R.