US2864284A - Apparatus for interrupting the formation of transverse rents in paper webs - Google Patents

Description

,1958 H. PROFFEN 2,864,284

APPARATUS FOR INTERRUPTING THE FORMATION OF TRANSVERSE RENTS IN PAPER WEBS Filed March 25. 1954 2 Sheets-Sheet l fig. I

Dec. 16, 1958 H. PROFFEN 2,864,284

' APPARATUS FOR INTERRUPTING THE FORMATION OF TRANSVERSE RENTS IN PAPER WEBS Filed March 25. 1954 2 Sheets-Sheet 2 Fig.4

St tes APPARATUS FOR iNrnnnUPTING THE FORMA- TIoN or TRANSVERSE RENTS IN'PAPER WEBS It has been known to those familiar with the art of paper-making that the frequent occurrence of transverse tears or rents in the web of paper resultsin considerable losses. None of the means heretofore proposed for the purpose of interrupting the formation of tears or rents such as are particularly apt to develop in the web of paper as it leaves the suction drum or roller have thus far proved to be adapted successfully and reliably to interrupt the further development of the said rents once they have started to form. To an even lesser extenthas it thus far been possible, after stopping the further development of a rent, to restore the web of paper to its full width without resorting to the use of an auxiliary coucher of known construction. i

The heretofore known. arrangements intended to prevent the web of paper from being torn during. the process of-manufacture, even though they may be designedfor fully automatic response to the development ofthe said rents and/ or for the subsequent restoration of the paper web to its full width, have been cumbersome in use and uneconomical in operation. Besides that,.the. detecting devices provided in said known arrangements. for the purpose of causing the intercepting devices to respond to the inception of a rent or tear have-not been completely .re-

liable in practice as regards proper response to the inception of rents or tears. This isaccounted for by the relatively long period of delay elapsing between the response by the said'detecting devices and the action of the,said intercepting devices. Despite the use of expensive detecting devices, this drawback of the said known: arrangements results in conditions under which the-web of paper will be completely torn through during the manufacturing process, whereby frequent stoppages are caused as a result.

. of which it becomes necessary to go-through the tedious andrtime-consurning steps of re-starting the web of paper.

It is one-of the objects of the.present invention to eliminate the above-mentioned serious shortcomings of said known arrangements intended to intercept the development of transverse rents in webs of paper during their manufacture, in particular, and to re-start a full-width web. According to the invention,.any incipient rents in the paper web are detected by means of per-se known radiation-sensitive cells arranged to respond to the start-- ing of any transverse rent in such a manner as to actuate either side of the paper Web center line with radiationemitting means which are also arranged on either side of the said center line. In this arrangement the fact is taken into account thatunder certain circumstances the intercepting device which may, for example, take the'form of a jet nozzle of known design, becomes operative at a atent of suitably timed switching .operaions.

2,8642% Patented Dee. to, 1955 ice point spaced a certain distance from the end of the incipi ent crack or rent. However, the invention, while aiming at complete elimination of conditions under which the web ofpaper is completely torn through, also contemplates the use of means of the simplest possible design, thusproviding for maximum economy. The above-mentioned reciprocal association between the intercepting device located at a point spaced laterally from the web center line with an origin of radiation adapted. to become operative on the other side of the web center line, i. e., for example, the point of intersection between a pencil of light and the web of paper, ensures reliable interception of any incipient rent even in cases in which such rent develops at ahigh rate of speed in a transverse direction relative to the web of paper. The time lead with which the rent-limiting perforation is made in the web of paper, for example by a jet emerging from a nozzle, will then in all cases be sufficient to prevent any incipient rent from extending throughout the width of the paper web.

in another embodiment of the invention, in which the hereinbefore mentioned method according to the invention may under certain circumstances even be dispensed with, the heretofore known means may be simplified considerably by the use, also according to the invention, of an endless belt carrying the above-mentioned pair of intercepting devices and adapted to be driven from a single point by a suitable drive motor.' In this embodiment the structural simplification resides not only in the use .of a single drive motor but also in the attendant reduction in the amount of control equipment required, especially in the case of fully automatic operation.

It is such fully automatic operation that is provided for, according to the invention, in an embodiment adapted to perform the above-mentioned functions according to the invention, this being achieved by using a pair of interlocked relay-controlled switch contact sets, one of these switch contact sets being operatively associated with each of the two radiation-sensitive.cells, the said sets of switch contacts being used, in combination with time delay relays for the energization of the single drive motor andin combination with limit switches associated with the movable jet nozzles, to initiate the various functions without-any manipulation on the part of theoperating personnel, the required sequence of operations being obtained by means The jet nozzles used in this embodiment as intercepting devices are con trolled'in a per se known manner by solenoid valves. In.

a specific embodiment of the invention the discharge openings of the said nozzles are inclinedin relation to the web ply lines may be adjustably supported above the said web by suitable toggle joint means, whereby an arrangement is obtained that offers advantages over prior art arrangements in that the paper web is vertically spaced below the jet'nozzles in a more favorable manner and that the nozzle heads may be given an additional rotation during their transverse travel relative ot the web of paper, whereby a further improvement in the cutting. edge is secured.

The invention is further described with reference to the appended drawings, certain additional features of the machine and particularly shows the arrangement and the ting fully automatic operation of a device according to the invention, said arrangement comprising a manually operated four-tier change-over switch adapted to permit the starting of a web of paper at the time'when operation of the machine commences, this starting operation being performed with the aid of those means which serve to produce the above-mentioned intercepting action and the subsequent re-starting of a paper Web.

As will be seen in Figures 1 and 2, the suction roller 1 is supported by its shaft 2 which in turn is carried in suitable bearings provided on the frame members 3 and 4 i of the paper-making machine. The said frame members also serve as supports for the two light sources 5 and 6 which are arranged to project a strongly concentrated beam or pencil of light on the respective photo- electric cells 7 and 8 associated therewith, the said pencils of light having their axes arranged at an angle in relation to the axis of the suction roller. The photo-electric cells are mounted on the housings 9 and 10, respectively, through the medium of brackets 11 and 12, the said housings being supported by the frame members 4 and 3, respectively. While housing 9 contains an amplifier for the current produced by photo-electric cell 7, housing accommodates an amplifier associated with photo-electric cell 8 and. the drive motor for an endless belt adapted to change the respective position of the jet nozzles 13 and 14 along their associated guide means 15 and 16 (see Fig. 3).

As will be seen in Figure 3, motion may be imparted to the jet nozzles 13 and 14 by means of a motor-driven pulley 17 arranged to drive the endless belt 18. Whenever such motion is imparted to the nozzles, they are displaced along the rod- like guide members 15 and 16, re spectively, which are arranged above suction roller 1. The drive pulley 17 is suitably supported for rotation on the housing 10. The idler pulley 19 over which the endless belt 18 is trained near the other end of the suction roller 1, is supported for rotation on housing 9. The toggle joints 20 and 21 which are also supported by the housings 9 and 10 near either end of roller I carry the water supply lines 22 and 23 for the jet nozzles 22 and 23, respectively.

The machine wire 25 serves to convey the paper web 24 to the suction roller 1. At the point 26 the paper web disengages itself from the suction roller and is transferred thereafter to an endless belt band 28 trained over i a drum or pulley 27 (see Fig. 2 and Fig. 3). The pencil of light emitted by source 5 strikes the web of paper 24 at a point of intersection 29, while the pencil of light emitted by source 6 crosses the plane of the paper web at 30 (Fig. 1). It will be appreciated that as long as no rent occurs along the line 26 at which the paper web is disengaged from the suction roller 1, the beams of light emerging from the sources 5 and 6 will be stopped by the paper web 24 and will thus be prevented from reaching the photo- electric cells 7 and 8. However, it is obvious that this control arrangement of which the radiationsensitive cells 7 and 8 are the primary components will immediately come into action as soon as a transverse rent starts to develop in the web of paper, that is tosay, as soon as the starting point of such rent travelspast the plane which contains the said pencils of light.

For example, in the event a rent should start at the left-hand edge of the paper web as seen in Figure 1 as the web leaves the suction roller 1,-the incipient rent starting to extend towards the central portion of the web, the beam of light projected by source 5 willno longer be stopped by the web but will immediately strike the photo-electric cell 7. The photo-electric current produced by this cell will be amplified by the amplifier provided in the housing 9, the amplified current then opappreciable delay; in the present example, the jet nozzle 13 will be rendered operative, said nozzle discharging a fine fluid jet which, in accordance with known practice, will cause the web of paper to be slotted in a longitudinal direction. According to the invention it is of particular importance that upon the web of paper 24 beginning to be torn from the left towards the right as seen in Figure. 1, i. e. upon the photo-electriccell 7 being rendered operative, that jet nozzle (nozzle 13 in the present example) should be coming into action which is located in the opposite half of the paper web 24 to that half of the web in which the point of intersection 29 between the light beam under consideration and the plane of the paper web is located. On the other hand, had the tear ing of the paper web 24 started from its right-hand edge as seen in Figure 1, the beam of light emitted by the source 6 would no longer have been stopped at the point of intersection 30 but would have struck the photo-electric cell 8. In the latter case, the photo-electric current produced by cell 8 and amplified by the amplifier provided in housing 10 would have caused the jet nozzle 14 to come into operation; again in this case the jet nozzle in question, i. e. nozzle 14, would be located on the opposite side from the paper web center line in relation to the location of the point of intersection 30. Because of this hereinbefore mentioned reciprocal correlation between the interception devices, i. e. the jet nozzles, arranged on either side of the web center line and the said points of intersection 29, 30 which are also located on either side of the said center line, any incipient rents starting from the edges of.the paper web 24 will cause the detecting devices to respond in a suitable manner, as the slotting of the. paper web in its direction of travel by the fluid jets issuing from the nozzles 13 or 14 has long been performed already whenever a rent has reached the slot produced by the fiuid jet, the result being that the paper web is in all cases prevented from being torn completely. Similar conditions apply in cases in which rents start from a point located in the central portion of the paper web, this type of rent, by the way, occurring less frequently. For example, assuming that a rent starts to the left of the point of intersection 29 and that said rent develops towards the center line of the web, the said rent will be detected by the beam of light traversing the point 29 and striking the photo-electric cell 7, whereby the rent 18 limited by the longitudinal cut produced by the jet or fluid discharged by nozzle 13.

The arrangement illustrated in Figures 1 to 3 will not only intercept any incipient transverse rents developing in the paper web 24, but it also renders it possible, as mentioned earlier in this description, fully automatically to cut out such rents. For this purpose that jet nozzle which was used to produce a longitudinal cut in order to intercept a rent in the web of paper is moved by means of. the drive pulley 17 and the endless belt 18 (Fig. 3) along its guide rod towards that side from which the rent had started before it was intercepted; during this action the longitudinal travel of the web of paper is not interrupted. Assuming, in similarity to my first example, that the rent has developed from the left-hand edge of the paper web as seen in Figures 1 and 3 towards the center of Web 24, pulley 17 is rotated in an anticlockwise direction to move the endless belt 18 in such a manner as to displace the nozzle 13 on its guide rod 16 towards the left-hand edge of the web 24, whereby the fluid jet continuously cuts the paper web in such a manner that as to re-start a sound web whose width increases continuously until its original width has been fully restored, the latter being the case when the jet nozzle 13 has during this action reached the left-hand edgc of the web of paper. Since the discharge head of the nozzle 13 is set at an angle in relation to the plane of the web 24, and since the folding action of the toggle joint 20 during the displacement of the said nozzle along its guide rod 16 towards the left-hand edge of the web 24 rotates the said nozzle, a smooth cut along the line of separation will be produced.

"As will be seen from the wiring diagram of Figure 4, each of the two housings 9 and 10 accommodates an 'amplifier arrangement, the amplifier in housing 9 comprising an electronic tube 31 and the amplifier in housing 10 comprising an electronic tube or valve 32. Heating up of the tubes or valves 31 and 32 will produce plate currents enabling the magnet coils 33 and-34 to attract their respective armatures 35 and 36. This will close the circuits containing the glow lamps 37 and 38, respectively, the lighting-up of these lamps indicating that the installation is ready for operation. Thereupon the tumbler switches 39 and 40 are closed, whereuponithe installation is ready to operate to intercept incipient rents in the web of paper and fully automatically to cut out the rent portion of the web.

In the event an incipient rent causes light to fall on the photo-electric cell 7, the plate current in the amplifier 9 or rather in tube 31 is interrupted, this causing the armature 35 to drop back into the position indicated in Figure 4. This switching action establishes a closed circuit for the energization of the solenoid 41, said circuit extending from fuse 42 via tumbler switch 39, armature 35, series resistance 43 and contacts 44, 45 of switch contact set 46 of relay 47 to fuse 48. This willcause the position of the switch contact set 49 of. relay 41 tobe changed, whereby contact is made between contacts. 50 and 51, contacts 52 and 53, and contacts 54 and '55, while contact is broken between contacts 54 and 56 and contacts 52 and 57. The separation of the contacts '52 and 55 will open the coil circuit of relay 47, the result being that the latter is locked.

The action of separating the contacts 54 and 56 will interrupt the line leading to contact 58 of limit switch 59. Finally the making of contact between contactsSZ and 53 establishes a circuit between fuse 48 and solenoid valve 60, causing the jet nozzle 13 associated'with this valve to come into operation.

By way of contacts 54,55 the fuse 48 is connected via contacts 61 and 62 of switch contact set 46 to the-time delay relay 63, whereupon the latter relay will pull up, closing contacts 64 and 65 after a period of delay the length of which can be pre-determined or adjusted. The closing of contacts 54) and 51 establishes a circuit ex- .tendingfrom fuse 42 via contacts 66, 67 of limit switch 68 to contacts 69 and 70 of the motor relay 71.

Upon the closing of contacts 64 and 65 after the delay period has elapsed the fuse 48 is connected via contacts 64 and 65 to the motor relay 71, whereupon the latter will switch over.

This switching action will cause the motor relay 71 to close its pairs of contacts 70, 72 and 73, 74. This will start the rotor of the single-phase A. C. motor 75 in an anticlockwise direction of rotation, as now a circuit has been established from fuse 76 via terminal 77 of the stator winding 78, contacts 79, 88 of motor relay 81, the rotor winding 82-83, and contacts 73, 74 of motor relay 71 to the fuse 84. The A. C. motor 75 now drives the pulley 17 which in turn drives the endless belt 18, causing the jet nozzles 13 and 14 to travel towards the center of the paper web. Upon the starting of jet nozzle 13 the return travel is prepared by a closing action of limit switch 59 whereby contacts 58 and 85 are closed.

The switching-over of motor relay 71 causing the contacts 69, 86 to close has also closed the holding circuit of the relay 41. Now if the photo-electric cell 7 is prevented from receiving any light while the rent is being cut out, this causing the armature 35 to be again attracted by the electromagnet 33, the armature thus assuming its position of readiness in case another rent should start from the same edge of the web of paper, the relay 41 cannot drop but will have to await completion of the entire cycle of operation, as the solenoid coil 41 is now connected in a closed holding circuit extending from fuse 48 via contacts 45, 44. of. switch contactis'et :46, solenoidcoil 41, series resistance 43,-contaets 69. and 86 of motor relay 71, contacts 67, 66 of limit switch 68 and contacts 51, 50 of switch contact set 49. to fuse:42.

As soon as the nozzles13 and 14 reach their extreme positions, jet nozzle 14 will open the limit switch 68,:thus opening theihereinbefore described holding circuit by opening the contacts 66, 67. This will cause the switch contact set 49 to drop into its home position. The opening of contacts 52 and 53 causes the solenoid valve 60 to be closed, this rendering the jet nozzle 13 inoperative.

The opening of contacts 54, 55 also opens the coil circuit of the time delay relay 63. As a result, this relay drops and thus opens contacts 64, 65. This will deenergize the coil of motor relay 71, causing'this relayto drop and thus to open themotor circuit for left-hand rotation by separating contacts 73, 74.

The return movement. of the switch contact set'49 into its home position contacts 54, 56 have again been :closed. This establishes a return circuit extending from fuse48 via contacts 61, 62 of. switch contact set 46, cont-acts 54, 56 of switch contact set 49, contacts 58, 85 of limit switch 59, contacts 87, 88 0f the four-tier change-over switch 89, the coil'of time delay relay 90 and 'contact s 9'l, 92 of. change-over switch 89 to fuse 42. As a result, the time delay relay 9t) pulls up and, aft-erit'he preselected period of delay has .elapsed, closes the coil energizing circuit of motor relay 81, this circuit extending. from fuse .48 via contacts 93, 94 of time delay relay=90, the-coil of motor relay 81 and the series resistance 95 to fuse '42. Once this circuit has been established, motor relay 81 will pull up its armature, thus opening contacts 79, 80

- and simultaneously connecting the motor forclockwise .rotation by closing contacts 80, 96.

Now a closed-circuit extends from fuse 76 via terminal 77 of stator wind in}; 78, contacts 97, 73 of motor relay 71, rotor winding -82-a-83,:.aridcontacts '80, '96 of relay 81 to fuse-84.

85. This will also cause both the time delay relay-9 and the motor relay 81 to drop again.

The above-described functions of energizing the sole noid valve 60 will simultaneously put into operation the rent counter 98 for one edge of the paper web (for example on the side faced by the operators), the visual indicator panel 99 on the said side and the warning bell 100, the items just mentioned remaining in operation as long as the solenoid valve 60 operates. In a similar manner the rent counter 181, .the visual indicator panel 102 and again the warning bell 160 will be operated when any rent occurs on the other edge of the paper web (i. e. on the drive'side of the machine).

In order to make it possible, as has already been mentioned, tostart a web of paper when the machine is put into operation, the multi-tier change-over switch 89 is placed into its second operative position, whereby the circuits of the counters 98 and 101, of the visual indicator panels 99 and 102 and of the warning "bell are interrupted by opening the contacts 92, 91. In addition'the contacts'87, 88 of the return circuit are opened, while the contacts 103, 104 of the motor circuit for counterclockwise rotation are closed as described earlier, the onlyexception being that the time delay relay is bypassed. This will cause the jet nozzles 13 and 14 to be moved into their relative extreme positions without their associated solenoid valves (e. g. 60) being actuated. Upon f'the change-over switch 89 being brought into its third posi tion, the contacts 103, 104 are again opened to cause the two nozzles 13 and 14 to remain stationary. With the change-over switch 89 in its fourth position, contacts 103,. 105 are closed so as to close the return circuit for the motor, while bypassing the time delay relay, whereby tioned above.

the jet nozzles are caused again to move towards their starting position. With the change-over switch in its fifth. position, the last-mentioned circuit is again opened, the contacts 103, 106 being closed, causing the jet nozzle 13 to discharge fluid while standing still. By bringing the switch 89 into its sixth position, the motor circuit for the return travel is again closed. Now the nozzle 13 will continue to travel while discharging fluid. With the said change-over in its seventh position, either jet nozzles 13 and 14 will remain stationary, the nozzle 14 being turned on, while the nozzle 13 is turned off. With the change-over switch in its eighth position, the nozzle 14, while discharging fluid, will travel towards the left until it reaches its extreme position, thus cutting the web of paper over its entire. width. Moving the change-over switch beyond its eighth position will cause it again to assume its starting position, i. e. the first position men- Since the jet nozzles 13 and 14 are now in their respective extreme positions, the return circuit is closed via the time delay relay 90, thus causin the nozzles 1.3 and 14 to return to their starting positions without discharging any fiuid.

The individual component parts of the switching and control arrangement for the above-mentioned sequence of operations may be comprised into suitable units permitting the use of a sectionalized or compartmentized arrangement. For example, the counters, the change-over switch and the signalling equipment may be housed in one cover of a common casing, while the amplifiers and the sets of relays as well as the drive motor may be accommodated in the other cover of the casing.

The cutting of the web of paper may be performed by a fine jet of gas, especially of air, or by a mechanical device instead of the above-mentioned fine jet of water. Where a gaseous fluid is used in the cutting operation, the discharge nozzle will have to be of suitable design. The mechanical cutting device, if and when used, may comprise cutting knives the blades of which may be either stationary or rotating.

I claim:

1. In a paper making machine including means for feeding a paper Web the improvement that comprises a pair of cutting means normally positioned above said web and on either side of the longitudinal axis of the 'web, and control means operable when a break occurs in the web for moving the cutting means located on the opposite side of the longitudinal axis of the web from the break in the direction of the break transversely of the web.

2. In a paper making machine as defined in claim 1 the further improvement of said cutting means including an endless 'belt, two break intercepting devices mounted on said endless belt, and a motor for driving said endless belt.

3. In a paper making machine as defined in claim 2 wherein said intercepting devices comprise solenoid-valve controlled jet nozzles, the heads of said nozzles being arranged to discharge toward said web of paper and at an angle thereto.

4. In a paper making machine as defined in claim 3 wherein the lines serving to supply said jet nozzles are supported laterally of the said web of paper and that said nozzles are adjustably supported above the said web by toggle joint means.

5. In a paper making machine as defined in claim 3 wherein said control means includes radiation sensitive cells and in association therewith one relay-controlled set I of switch contacts, the said sets of switch contacts being 6. In a paper making machine as defined in claim 5 wherein the switching and actuating equipment controlling the said sequence of operations is integrated into sectionalized units.

7. In a paper making machine as defined in claim 5 wherein a four-tier change-over switch is connected in the full-automatic control circuit for the individual operations in such a manner that the drive means for the jet nozzles may also be used to start a web when the manufacturing operation is commenced, the individual phases of the starting-up process being associated with corresponding positions of the said change-over switch.

8. In a paper making machine as defined in claim 5 wherein one of the solenoid valves for the jet nozzles is o erated, a rentcounter is simultaneously energized.

9. In a paper making machine as defined in claim 5 wherein the solenoid-valve controlled nozzles serve to control the discharge of a fine jet of gas or air.

10. In a paper making machine as defined in claim 5 wherein the said intercepting devices are comprised of knives having stationary blades.

11. In a paper making machine as defined in claim 5 wherein the said intercepting devices are comprised of knives having rotating blades.

12. In a paper making machine including means for feeding a paper web the improvement that comprises a pair of cutting means associated with said web and normally positioned on either side of the longitudinal axis of said web, break detection means adapted to differentially sense breaks in the portions of said web on either side of the longitudinal axis of said web, means responsive to said break detection means sensing a break in one portion of said web to render said cutting means positioned on the opposite side of the longitudinal axis of said web operative, means responsive to a predetermined operation of said cutting means to move said cutting means transversely across said web in the direction of the remote edge of said web, and means responsive to arrival of said cutting means at the remote edge of said web to render said cutting means inoperative and to return said cutting means to its normal position.

13. In a paper making machine as defined in claim 12 the further improvement of said pair of cutting means being mounted on an endless belt arranged to travel in a plane substantially parallel to the plane of said web.

14. -In a paper making machine. including means for feeding a paper .web, the improvement comprising a pair of cutting means associated with said web, means normally supporting said cutting means at opposite sides of the longitudinal axis of the web, respective break-sensing means at said opposite sides of the web, means responsive to the operation of the break-sensing means at one side of the web formed and arranged to render the cutting means at the opposite side of the web operative, and means responsive to the operation of the last-named cutting means for a predetermined period of time to move said last-named cutting means transversely across said web in the direction of said one side of the web.

15. The structure of claim 14, and means responsive to the arrival of said last-named cutting means at the edge of said one side of the web to terminate operation of said last-named cutting means and to return said lastnamed cutting means to its normal position.

References Cited in the file of this patent UNITED STATES PATENTS 1,662,200 Merrill Mar. I3, 1928 1,725,108 Smith Aug. 20, 1929 1,838,603 Witham Dec. 29, 193] FOREIGN PATENTS 365,184 Great Britain Jan. 18, 1932 539,144 Germany Nov. 23, 1931 656,506 Germany Feb. 9, 1938

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