US2258816A

US2258816A - Cyclical knife adjustment

Info

Publication number: US2258816A
Application number: US318294A
Authority: US
Inventors: Albert F Shields
Original assignee: S&S Corrugated Paper Machinery Co Inc
Current assignee: S&S Corrugated Paper Machinery Co Inc
Priority date: 1940-02-10
Filing date: 1940-02-10
Publication date: 1941-10-14
Anticipated expiration: 1958-10-14

Description

Oct. 14, 1941. A. F. SHIELDS CYCLICAL KNIFE ADJUSTMENT Filed Feb. 10, 1940 4 Sheets-Sheet l S R Y o E a mu m W 0 NM w Oct. 14, 1941. A. F. SHIELDS CYCLICAL KNIFE ADJUSTMENT 4 Sheets-Sheet 2 Filed Feb. 10, 1940 F| (3.3- INVENTOR.

wharf 5K Shields ATTORNEYS Get. 14, 1941. SHIELDS 2,258,816

CYCLICAL KNIFE ADJUSTMENT Filed Feb. 10, 1940 4 Sheets-Sheet 4 INVENTOR. mam ,8? shields ATTORNEYS Patented Qct. 14, 1941 CYCLICAL KNIFE ADJUSTMENT Albert F. Shields, Jamaica, N. Y., assignor .to S. & S. Corrugated Paper Machinery Co., Inc., Brooklyn, N.Y., a corporation 01' New York Application February 10, 1940, Serial No. 318,294

19 Claims. (01. 164-68) This invention relates to cutting knives and more particularly to synchronously operated knives adapted to cooperate with a continuous web moving at a constant speed and arranged to cut sheets of predetermined length without interfering with the continuous movement of the web and irrespective of the average circumferential speed of the knife.

For this latter purpose, this invention also relates to the means for varying the circumferential speed of rotating knives during a cycle thereof so that while the average circumferential speed may be different from the linear speed of a continuous web with which the knife coopcrates, the circumferential speed during the period when the cutting operation takes place will be the same as the linear speed of the web.

Ordinarily where sheets of only one particular length are to be cut from a continuously moving web, the circumference and speed of rotation of the knife drum may be so arranged that the circumferential speed of the knife blade will always be equal to the linear seped of the continuous web. The knife blade meets the web once during each revolution, effecting the cutting operation as it passes along with the -web .at the speed of the web, and then meeting the web once more at a distance from the original cut equal to the length of sheet desired. Problems of adjustment arise when sheets of different length must, at different times, be out by the same .machine;

Theproblems of adjustment of circumferential speed of the knife during a single revolution thereof so that the knife will be moving at the speed of the paper during the actual cutting operation and so that the average speed of rotation of the knife drum may be such as to give the predetermined sheet length which will not 4 'van'ed once during a particular revolution of the knife drum. This'has been accomplished, for instance, by the crank and bifurcated arrangement-shown in Patent No. 2,070,386, or by the quadric chain arrangement shown in application other means such as that shown in application Ser. No. 320,571, filed Feb. 24, 1940.

Although a universal joint is commonly known and understood, nowhere in the prior art 0. in

the industry has there been any demonstration .or teaching of the use thereof in connection with rotating knives, the speed of rotation of which may be varied with respect to the continuously moving web in order to obtain cut-oif sheets of different lengths (the speed of the knife drum being varied so thatit will be exactly that of the continuously moving web during the cutting operation).

The novelty of the present invention resides therefore in the use of a universal joint forming part of the power path to the cutting knives for the purpose of cyclically adjusting the speed of the cutting knives so that whatev'erthe average speed thereof, they will be traveling at the same speed as the continuously moving web with which they cooperate at the time that the actual cutting process is taking place, the predetermined average speed of the knives for selected sheet lengths being nevertheless maintained by a change of speed of the rotation of the cutting knives in an opposite sense (either a slowingdown or speeding-up) during the revolution thereof.

Objects of this invention, therefore, are to provide in connection with cutting knife mechanisms which are to operate cyclically upon continuously moving webs for the purpose of cut 0 matic adjustment by providing a universal joint in the power path to the cutting knives.

Still another object of this invention is to pro vide a means for varying the angle formed between the shaft. connected by the universal joint for the purpose of changing the cyclical varia tion in the speed of rotation of the cutting knives in order to enable the cutting of different sheet lengths.

Other objects and uses of the present invent1on will in part be apparent and in part be pointed out in the following, description and drawings in which:

Figure 1.15 a schematic view in perspective showing the general organization of my inven- Ser. No. 2,208,350, issued July 16, 1940, or by tlon with particular emphasis on the provision the remainder of of a universal joint in the power path to the rotating cutting knives for the purpose ofimpinging upon the average rotation thereof, a cyclical variation in such rotation.

Figure 2 illustrates a slightly modified form of the apparatus of Figure 1 showing an arrangement of the cutting knives which utilizes each of the variations induced by the universal joint as hereinafter explained.

Figure 3 is an end view of Figure 2 showing the universal joint adjusted for a position which induces cyclical variations in the speed of rotation of the cutting knives.

Figure 4 illustrates in top plan view partly in cross-section a modified form of the constructions of either Figure 1 or 2 wherein the universal joint angle may be varied in a different plane for accomplishing the same purpose.

Figure 5 is an end view of Figure 4.

Figure 6 illustrates in diagrammatic perspective a slight modification of the form shown in Figure 4 wherein the angle of the universal joint may be varied in two planes.

Figure 7 is a diagram illustrating the varla-,

tions in position of the members of Figure 6.

Referring now to Figure 1, it should be noted that the position of the universal joint here shown is such that no cyclical variation in the speed of rotation of the cutting knives will ensue while when the universal joint is moved so that the shafts which it connects are no longer coaxial, to for instance a position similar to that shown in Figure 3, cyclical variation in the speed of rotation of the cutting knives will be effected.

In Figure 1 I have shown a cutting machine wherein the continuously moving web is fed by the feed rollers I I and [2 in the direction indicated by the arrows between the cutting knives l3 and I4 which are respectively mounted on the drums l5 and IS. The speed of movement of the continuous web I0 is constant, the feed rollers H and I2 being caused to rotate at the constant speed by power transmitted thereto from the power shaft l1, sprocket I8, chain l9 and sprocket 20.

The knife drums, however, are not connected directly to the power shaft although they are driven from the shaft. Where, for'instance, a continuous web is moving at a speed of 120" per minute and it is desired to obtain 30" sheets therefrom, it will be necessary for the drums of the knife shaft to rotate four times per minute. Where a variation is desired and 60" lengths are required, then the knife drums must be caused to rotate twice per minute while for 120" lengths the knife drums must rotate once per minute.

Owing to the fact that corrugated sheet material is fairly heavy, it is necessary to have a shearing action in cutting the sheet material so that the sheet material is out not at a single moment but over a relatively short period. During this short period, whatever the average speed of rotation the knife drums require in order to obtainsheets of desired length, it is necessary that the knives themselves move at the exact speed of the paper, any speeding up of the knife drums necessary to accomplish this purpose being compensated for by a corresponding slowing down of the knife drums at a time when the knives are not in engagement with the sheet.

In order to provide for variations in the speed of rotation of the knife drums and in order to obtain sheets of varying length, a Reeves drive It is interposed in the power path between the power shaft I1 and the knives. The Reeves drive comprises as will be noted, cones I9 and 20 and belt 2| interconnecting the two. Movement of the belt back and forth upon the cones will result in variations in speed imparted to the shaft 22 of the Reeves drive in a manner which is now well known in the art.

Shaft 22 of the Reeves drive is keyed to and drives gear 23 which meshes with gear 24 which in turn is keyed to shaft 25 and drives the same. Shaft 25 carries at the opposite end thereof bevel gear 26 which meshes with bevel gear 21 thus causing shaft 28 to rotate which through the universal joint 29 causes the shaft 30 and its associated gear 3! to rotate.

Rotation of gear 3| causes the rotation of gear 32 which in turn causes shaft 33 to rotate thereby rotating knife drum is which carries the knife I4. Rotation of shaft 33 likewise through gears 34 and 35 causes rotation of shaft 38 which in turn rotates the knife drum (5 carrying the knife 13.

Variation in average speed of rotation of the knife drums is accomplished therefore by movement of the belt 2! of the Reeves drive upon the cones thereof in order to obtain variations in the speed of the shaft 25 in a manner well known in the art.

With the universal joint in the position shown in Figure 1, no other variation in the speed of rotation of the knife drums l5 and 16 occurs. But when the shaft 28 is moved to a position similar to that shown for instance in Figure 3 where it is no longer coaxial with shaft 30 but rather it is at an angle thereto, cyclic variations in the speed of rotation of shaft 30 and consequently in the speed of rotation of drums I5 and I6 and their associated knives will occur.

In order to provide an adjustment which will readily move the shaft 28 to a position at an angle to and non-coaxial with the shaft 3|] bearing gear 3| and therefore in order to provide a means for cyclically varying the speed of rotation of the drums l5 and I6, I have added the series of adjustments shown particularly in Figure 1. Thus the shaft 28 is rotatably mounted in the sleeve 31 which is part of a casting 38 hereinafter more particularly described. The shaft 28 also carries either keyed thereto or as a part thereof the bevel gear 21 and also carries the

tangs

39 and 40 for rotatably supporting the rod4l of .the universal joint.

When bevel gear 26 therefore rotates bevel gear 21 and causes a rotation of the shaft 28 it likewise by means of the

tangs

39 and 40 causes a rotation of the rod 4| of the universal joint 29. This rod 4| is integral with rod 42 of the universal joint 29 and is at right angles thereto.

Rod 42 of the universal joint is rotatably supported in the tangs 43 projecting from the face of the gear 3| which may be regarded as an extension of the shaft 30. The casting 38 pivots about the shaft 25 on its sleeve 45. The casting 38 also carries a segment of a worm gear wheel. Control shaft 41 carries at one end thereof the spiral gear 48 which meshes with the teeth of the gear segment 46. Rotation of the control shaft 41 by, for instance, the handle 49 will cause a corresponding rotation of the spiral gear 48. The control shaft is mounted in such manner that it cannot shift longitudinally along its axis. Therefore rotation of the spiral gear 48 will result in a corresponding movement in one direction or the other of the segment. Since the segment 48 is integral with or securely attached mains enmeshed whatever the angular position of the shaft 28 with respect to the shaft 38 so that whatever the angle at which the universal joint is placed, the power transmitted to shaft 28 is always constant and unvarying.

I have found that when the shaft 28 is at an angle to the shaft 38 as for' instance in the manner shown in Figure 3, then although the shaft 28 rotates at a constant speed, the rotation of shaft 38 will vary cyclically. Thus when the shaft 28 is at an angle such as that shown in Figure 3 with respect to the shaft 38 and when the rods 42 and 4| of the universal joint are in the postlon shown with respect to each other, and with respect to the angle formed between the shafts, then the shaft38 will be rotating at a speed which is less than that of the speed of rotation of the shaft 28. When the shaft 28 has rotated through 90 so that the rods 4| and 42 of the universal joint also have removed to a position 90 from that shown in Figure 3, then the speed of the rotation of shaft 38 will be correspondingly greater than the speed of rotation of shaft 28.

Inthis case it will be noticed therefore that there are two maximum speeds and two minimum speeds of rotation ofshaft 38 in a single cycle, while the average speed of rotation of shaft 38 is the same as that of shaft 28. The variations from maxima to minima in the speed of shaft 38 .will vary in accordance with the angle which shaft 28 is caused to assume with respect to shaft 38. Since there are two maximum speed positions and two minimum speed positions in a single rotation of shaft 38' then the variation from the lowest speed to the highest speed takes place within an arc of 180. By a proper adjustment of the control shaft 41 and proper corresponding adjustment of the belt 2| of the Reeves drive l8, the cutting operation may be caused to take place at any desired point over any desired interval of said 180 at the moment when the circumferential speed of rotation'of the knife shaft is the same as that of the linear movement of the continuous web. Preferably, however, the ,cutting operation should take place at either a maximum point or a minimum point and the knives are so arranged that they will register with the paper only atmaximum or minimum points.

Since a complete cyclical variation in the speed of rotation of the shaft 38 can take place once in each 180, that is, the shaft may reach its maximum speed and drop to its minimum speed within 180 and since it will reach two such maximum within a full rotation of 360 then such elements may be utilized and the knife shafts may be caused to rotate twice for every single revolution of the shaft. 38 so that there will be only one maximum and one minimum cyclic speed within any single revolution of the knife shafts. 7

In order to accomplish this, gears 3| and 32 are in two to one ratio so that the shaft 33 rotates at twice the speed of shaft 38.

By proper calculation, calibration, testing and adjustment, the exact relationship between the angle at which the universal joint is placed and the position at which the belt 2| of the Reeves drive is placed may be obtained and since any movement of the belt 2| of the Reeves drive must necessarily require a corresponding movement of the shaft 28 to a different angle with respect to the shaft 38 then the'two motions may be inter-related and the very control shaft 41 which controls the angle which shaft 28 reaches with respect to shaft 38 may also be used to control the position of the belt 2| in the Reeves drive.

Thus bevel gear 58' on the control shaft 41 may mesh with bevel gear 58 at one end of shaft 5|, the opposite end of shaft 5| carrying the worm gear 52 which in turn meshes with the gear 53 carried by,the shaft 54. Rotation therefore of the handle 48 of the shaft 41 results as has been noted in rotation of shaft 41 causing an adjustment 'of the universal joint such rotation also resulting in a corresponding rotation of shaft 5| resulting also in a rotation of shaft 54.

Rotation of shaft 54 results in rotation of the cam 55 which bears upon the rotatable wheel 56 which is pivoted at 51 to the lever 58. Movement of the cam 55 will cause a change in the position of the wheel 58 with respect thereto and consequently will cause a movement of the lever 58- about its fulcrum 59.

Such movement of the lever 58 about its fulcrum 59 will, through the pin 88 and the link 5| carrying the members 62 which engage the belt, cause a corresponding movement of the belt 2| upon the cones of the Reeves drive.

Spring 53 will tend to cause a movement of the lever in the opposite direction from that induced by the eccentric 55 and therefore will cause the wheel 56 to bear against the eccentric 55, the motion of 'the eccentric 55 counteracting the force exerted by the spring 63.

Consequently, a single adjustment or rotation of the handle 49 will result in a variation in speed of rotation of the knife shaft in order to produce I be clear; the method here described is but one of and 3 instead of being of the same circumference and diameter as drum I5 is twice the circumference thereof.

By placing knife blades l4 and M" along the drum l6 and removed from each other, it

becomes possible without doubling the speed of) shaft 30' with respect to the shaft 28 to .utilize instance the cutting operation is to take place at the interval of maximum speed). Thus at one maximum interval knife M will be in engagement with knife l3, while at the second maximum interval during the same cycle knife l4" will be in engagement with knife I3".

Drum l5 may in one embodiment have the same diameter as drum l8 and a pair of knives 180 removed from each other in the same way to engage with the two knives of drum Hi. However it is possible and I prefer that the drum I5 have but the single knife l3 to engage once during each revolution of drum l5 with one of the knives of drum I5 and to engage once during each revolution of |6f alternatively with both of the knives of the latter drum.

For this purpose drum |5 (of Figure 2) should rotate so that the knife I3 is adjacent the sheet twice during every revolution of drum l6 and accordingly drum I5 should revolve at twice the speed of drum I6.

Consequently gears 34' and 35' are in exact 2 to 1 ratio in order to double the speed of drum I5 with respect to drum l6. Cyclic variations in speed may of course be accomplished in exactly the same manner and by the same apparatus as previously described in connection with Figure 1.

Various modifications and alternations of the form in which the universal joint is used are, of course, possible, the underlying essential element being at alltimes the interposition of the universal joint so that the angle between the power transmitting shaft and the driven shaft of the knife drum is variable for the purpose of varying cyclic speed.

Thus in the form shown in Figures 4 and 5, I havc shown a modification in which the Reeves drive connections and other connections of the apparatus may be the same as that for Figures 1 to 3 inclusive but wherein a compound universal joint arrangement is used so that the variation of the angle may be accomplished without power transmitting and operating shafts then the other universal joint is in exactly the same relationship. Thus in the position shown in Figure 4, the universal joint 82 is at a position be tween power transmitting shaft 28' and the operated shaft 8| at that moment of cyclic operation when the operated shaft 8| has reached its maximum cyclic speed.

Thus the two

universal joints

82 and 89 do not cancel the effect of each other but rather tend to multiply their effect producing a desired maximum speed with less angularity for each of the two universal joints than would be required in the case of a single universal joint direct connection between the power transmitting shaft and the knife carrying shaft.

It is, of course, obvious that when the power transmitting shaft 28 is at a position furthest moving shafts out of a single horizontal plane and wherein each joint is subjected to only half the angle of Figure 1 while producing the same overall angle. All of the apparatus (not shown) of Figure 4 up to and including the power shaft 25 is exactly the same as that hereinbefore de- 7 scribed.

Shaft 30 of the knife drum terminates in a universal joint 80 which connects the shaft 30' with the shaft 8|. Shaft 8| also terminates in a universal joint 82 which connects the shaft 8| with the power transmitting shaft 28'. Power transmitting shaft 28' rotates within the sleeve 83 which is a part of the sliding frame member 84. The opposite end of power transmitting shaft 28 carries the bevel gear 85. Bevel gear 28 1'0- tated by the power shaft 25 meshes with the bevel gear 85 and thus causes a rotation of the shaft 28' which through

universal joints

88 and 82 and shaft 8| results in the rotation of knife drum shaft 38 and therefore of the knife drums.

It will be seen that sliding of the frame member 84 back or forth in the direction indicated by the arrows will result in 'a change of the angles which the

universal joints

88 and 82 assume between their respectiveishafts.

The important angle of course is that between shafts 8| and 30'. But as shown, the

universal joints

80 and 82 are so arranged that they are continuously in similar relationship to their respective shafts, that is, when one universal joint is in position to result in a maximum speed increase during any particular cycle between the removed from coaxial relationship with the shaft 30' there is a greater distance between then than when the shaft 28' has reached a position substantially coaxial with shaft 30'. The universal joint 88 is therefore not connected directly to shaft 8| but is rather connected to a sleeve 86 which is slidably connected to shaft 8| by means of a feather key registering with the slot 81 of the shaft 8| in such manner that the sleeve 86 rotates with the shaft 8| but is free to move longitudinally thereof and thus in effect to lengthen and shorten said shaft and thus further compensate for any change in distance between shafts 28 and occasioned by movement of the slide 84 and the shaft 28' in the directions indicated by the arrows.

It should be noted that in the present modification the end of the power shaft 25 shown in the drawing of Figure 5 rotates in the

bearings

88 and 89 of the frame 90. The frame 90 carries the slide member 84 by means of suitable trackways or grooves 9| in the frame 98 which register with members of the slide 84 so that the frame 98 provides a key way or track way within which the slide member 84 may travel in a direction longitudinal to the shaft 25. By reason of these guides, the slide member 84 is fixed with respect to the frame 90 and.does not rotate with the shaft 25, the shaft 25 rotating also in bearings 92 and 93 of the slide member 84.

The bevel gear 28' is not mounted directly on the shaft 25 but rather is mounted on a sleeve 94 which is carried between the

pillars

95, 98 of the slide member 84 and which may rotate with respect thereto. The sleeve 94 carrying the bevel gear 26' is connected by feather key 91 to the shaft 25 so that although it may slide longitudinally with respect to the shaft 25, it necessarily must rotate therewith. In this Way, the bevel gear 28' rotates under the influence of the shaft 25 in the same manner as if it had been directly connected thereto but it is free to be moved 10ngitudinally of the shaft 25. The sleeve 94 serves accurately to fix the bevel gear 26 in a continuously fixed relationship to the

end pillars

95 and 88 of the slide member 84 and hence in a continuously fixed relationship to the bevel gear which is likewise supported by the slide member 84 so that the two

gears

26 and 86 are always in mesh.

The slide member 84 may be moved with respect to the frame for the purpose of changing the angles of the

universal joints

88 and 82 by means of the control shaft 98. Control shaft 98 is fixed to rotate in bearings 99 and I00 of the frame member 98 but in such a manner that the control shaft 98 is fixed within the frame memher so that it cannot move longitudinally with respect thereto. Control shaft 98 carries threads IOI which register and are in engagement with similar threads I02of a perforation of an extension I03 of the slide member. Rotation of the control shaft 98 results obviously in rotation of the threads and by reason of the engagement therewith by the threads I02 of the slide member necessarily results in movement of the slide member with respect to the control shaft. Rotation of the control shaft 98 therefore results in movement back and forth of the slide member 84 in a direction in accordance with the rotation of the control shaft.

I have here described but one means for moving the slide member 84 any other suitable means for accomplishing this purpose may be used. The

control shaft 98 may be interconnected and integrated with the control of the Reeves drive in a manner substantially similar to that shown in Figure 1. By this means, a cyclic variation or a plurality of cyclic variations may be obtained in the speed of rotation of the knife drums for the purposes hereinbefore described. In this way, the use of two universal joints, each in the same relative position between their respective shaft and each arranged so that they will always make the same angle between their respective shafts and thereby have an additive effect which will thus create the desired variation in cyclic speed with a smaller adjustment.

It should be noted that owing to the fact that shafts 28' and 30'- are so fixed with relation to each other that when they are not coaxial they must necessarily be parallel to each other insures that the shaft 8| which constitutes a straight line intersecting these two parallel shafts must always in every adjustment form angles of equal degrees with respect to each shaft 28' and,30', thereby assuring that

universal joints

80 and 82 will always be at the same angle.

In Figure 6 I have illustrated a slight modification of the construction of Figure 4 wherein the same double universal joint connection is used but wherein a gear segment instead of the sliding frame member arrangement of Figure 4 is used in order to obtain the adjustment. However, the power transmitting and ultimate power receiving shaft of the knife drum are continually and must necessarily remain in parallel relation to each other for the reasons before described.

Power transmitting shaft of Figure 6 terminates in gear 0 which meshes with gear III which therefore rotates the power transmitting shaft I28. The rotation of gear III and power transmitting shaft I28 results in rotation of the shaft 8| through the universal joint 82, the rotation of shaft 8| through universal joint 80 results in rotation of shaft 30' for the purposes hereinbefore described.

These shafts and universal joints operate in exactly the same manner as hereinbefore described; but here the control mechanism of I I mitting shaft I28 with respect to the ultimate power receiving shaft 39 and thereby results in placing the

universal joint

82 and 80 at the angles between shafts I 28 and 8| and shafts 30' and 8| in order to obtain the cyclic variations in speed hereinbefore described.

It should be noted, of course, that shaft I28 rotates in sleeve I3I which is mounted on or connected to the casting I29. A rack I32 in arcuate form is an integral part of or secured to the casting I29. Control shaft I33 carries worm I34 at theend thereof which mesh with the teeth of the worm gear I 32. Rotation of the control shaft movement of the gear I32 and therefore ina corresponding rotation of the casting I29 and a corresponding displacement of the shaft I28 and therefore in a placement of the shaft 8| at an angle with respect to both shafts I 28 and shaft 30' so that the

universal joints

80 and 82 are at the respective angles.

The control shaft I33 may, if desired, be integrated with the Reeves drive control mechanism in a manner shown in connection with Figure 1.

In all of the embodiments herein described, the sole function and operation of the mechanism is to place the ultimate power transmitting shaft at an angle with respect to the knife drum shaft so that cyclic variations in speed may occur.

The apparatus may be so arranged or set that the knife will engage the web to be cut when maximum cyclic speed is reached or when minimum cyclic speed is reached if that is desired (depending on whether the circumferential speed of the ,knife drums is greater or less than the linear speed of movement of the web to be cut) or any stage between the maximum and minimum cyclic speed may be selected.

Of course, it should be noted that the cutting operation is not here instantaneous so that the very instant of, for instance, maximum cycle speed cannot be selected for the cutting operation, but rather an average interval for cutting may be selected at the maximum speed where the average speed of rotation of the knife drums is less than that of the linear movement of the web.

Thus, as shown in the diagrammatic view of Figure 7, which is a diagram of the possible movements of the construction shown in Figure 6, the solid lines indicate a position of maximum speed of the knife drum I6.

It should be noted that the position for maximum speed may be selected at any point in the cycle, that is, 'the knife and the adjustments thereof may be so arranged that whatever the position of the shafts with respect to each other, the maximum speed may occur when the knives are in a vertical plane or it may even be arranged to occur when the knives are in a horizontal plane or at any intermediate point. The cutting knives first meet the sheet and begin to enter the same at a point somewhat removed from the vertical plane and-the cut is completed when the knives have reached the vertical plane so that where it is desired to obtain maximum speed of the cutting knives at the time they are actually in engagement'with the sheet material, such maximum speed should be attained when the knives first begin toengage the sheet of paper. This is the reason, therefore, that the preferred position of the knives for maximum speed is approximately that shown in the solid lines of the diagram of Figure -7.

In actual practice, however, and in order to distribute whatever errors may occur even though such errors may not be of extreme importance,

I33 results in a corresponding the cutting knives may be arranged to reach their maximum speed when they have already partially entered the web, and accordingly, the preferred position of maximum speed for the cutting knives may be that shown by the dotted lines of Fi ure 7.

Various other methods for utilizing universal joint connections in the manner herein described will now be obvious to those skilled in the art and various other means for supporting the movable shafts will also be clear. Accordingly, I do not intend to be limited by the specific disclosure herein, but only by the appended claims.

, I claim:

1. A means for cyclically varying the speed of rotation of a shaft while maintaining a constant average speed of rotation thereof; said means comprising a power transmitting shaft rotatable at unvarying cyclic speed, a universal joint connection between said power transmitting shaft and said first mentioned shaft, and means for varying the angle between said shafts.

2. A shaft rotatable at a constant average speed for each cycle of rotation, means for reducing the speed thereof during part of said cycle and increasing the speed thereof during the other portions of said {cycle while maintaining the constant average speed for each cycle, said means comprising a power transmitting shaft rotatable at unvarying cyclic speed, the end of said latter shaft being adjacent the end of said first mentioned shaft and disposable at an angle thereto, and a universal joint connection between said shafts.

3. A shaft rotatable at a constant average speed for each cycle of rotation, means for reducing the speed thereof during part of said cycle and increasing the speed thereof during other portions of said cycle while maintaining the constant average speed for each cycle, said means comprising a power transmitting shaft rotatable at unvarying cyclic speed, the end of said latter shaft being adjacent the end of said first mentioned shaft and disposable at an angle thereto, a universal joint connection between said shafts; and means for changing the degree of cyclic variation from average speed of said latter shaft.

4. A shaft rotatable at a constant average speed for each cycle of rotation, means for reducing the speed thereof during part of said cycle and increasing the speed thereof during other portions of said cycle while maintaining the constant average speed for each cycle, said means comprising a power transmitting shaft rotatable at unvarying cyclic speed, the end of said latter shaft being adjacent the end of said first mentioned shaft and disposable at an angle thereto, a universal joint connection between said shafts; means for changing the degree of cyclic variation from average speed of said latter shaft comprising means for changing the angle between said two shafts.

5. A method for creating cyclic variations in speed of rotation of a rotatable shaft operable from a power transmitting shaft, said method comprising the interposition of a universal joint between said shafts and placing said shafts at an angle of less than 180 and more than 90 to each other and means for selectively varying said angle.

6. An apparatus for successively severing sheets of predetermined length from a continuously moving web, said apparatus comprising a knife mounted on a rotatable shaft, a power source comprising a shaft and means connecting said power source and said rotatable shaft, means for selecting an average speed of rotation for said rotatable shaft, and means for cyclically varying the speed of rotation of said rotatable shaft, said means comprising a universal joint between said rotatable shaft and a portion of said means connecting the power shaft thereto and means for varying the angle between said rotatable shaft and said power shaft.

7. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft, and an auxiliary shaft, adjustable power transmission means connecting said power shaft and said secondary shaft for varying the average speed of rotation of said secondary shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft and means for placing said auxiliary shaft at an angle to said knife shaft.

8. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft and an auxiliary shaft, an adjustable power connection between said power shaft and said auxiliary shaft, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, and means for placing said auxiliary shaft at an angle to said knife shaft.

9. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft and an auxiliary shaft, adjustable power transmission means connecting said power shaft and said secondary shaft for varying the average speed of rotation of said secondary shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, means for placing said auxiliary shaft at an angle to said knife shaft, said auxiliary shaft being mounted in a sleeve perpendicular to said secondary shaft, said sleeve being rotatable about said secondary shaft, and means for rotating said sleeve carrying said auxiliary shaft.

10. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft and an auxiliaryshaft, adjustable power transmission means connecting said power shaft and said secondary shaft for varying the average speedof rotation of said secondary shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft comprising a bevel gear on each of said shafts, said shafts being perpendicular to each other and said bevel gears meshing with each other, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, means for placing said auxiliary shaft at an angle to said knife shaft, said auxiliary shaft being mounted in a sleeve perpendicular to said secondary shaft, said sleeve being rotatable about said secondary shaft, and means for rotating said sleeve carrying said auxiliary shaft.

shaft and said auxiliary shaft, comprising the mounting of said auxiliary shaft perpendicular to said secondary shaft and rotatable thereabout and a gear connection therebetween, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, and means for placing said auxiliary shaft atan angle to said knife shaft.

12. An apparatus for successively severing sheets of selected length fromacontinuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a second shaft and an auxiliary shaft, adjustable power transmission means connecting said power shaft and said secondary shaft for varying the average speed of rotation of said secondary shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft, comprising the mounting of said auxiliary shaft perpendicular to said secondary shaft and rotatable thereabout and a gear connection therebetween, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, means for placing said auxiliary shaft at an angle to said knife shaft, said auxiliary shaft being mounted in a sleeve perpendicular to said secondary shaft, said sleeve being rotatable about said secondary shaft, and means for rotating said sleeve carrying said auxiliary shaft.

13. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft and an auxiliary shaft, adjustable power transmission means connecting said power shaft and said secondary shaft for varying the average speed of rotation of said secondary shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft, a. universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, means for placingsaid auxiliary shaft at an angle to said knife shaft, said auxiliary shaft being mounted in a sleeve perpendicular to said secondary shaft, said sleeve being rotatable about said secondary shaft, and means for rotating said sleeve carrying said auxiliary shaft, said means comprising a gear segment carried by said sleeve, a gear meshing therewith, and means for rotating said ear.

14. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft and an auxiliary shaft, an adjustable power connection between said power shaft and said auxiliary shaft, a universal joint connection between said auxiliary shaft and said knife shaft, said auxiliary shaft being normally coaxial with said knife shaft, and means for placing said auxiliary shaft at an angle to said knife shaft, said means comprising a slidable mounting for said auxiliary shaft.

15. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft, an auxiliary shaft, and an additional shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft, a universal joint connection between said auxiliary shaft and said additional shaft, and a universal joint connection between said additional shaft and said knife shaft, said auxiliary and additional shafts being normally coaxial with said knife shaft, means for shifting said auxiliary shaft to non-coaxial position while its axis remains parallel to the knife shaft axis and placingsaid additional shaft at an angle to both said shafts.

16. An apparatus for successively severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft, an auxiliary shaft, and an additional shaft, an adjustable power connection betweensaid secondary shaft and said auxiliary shaft," a universal joint connection between said auxiliary shaft and said additional shaft, and a universal joint connection between said additional shaft and said knife shaft, said auxiliary and .additional shafts being normally coaxial with said knife shaft, means for shifting said auxiliary shaft in an arcuate path to non-coaxial position while its axis remains parallel to the knife shaft axis and placing said additional shaft at an angle to both said shafts.

17. An apparatus for successively I severing sheets of selected length from a continuously moving web, said apparatus comprising a rotatable knife shaft, a power shaft, a secondary shaft, an auxiliary shaft, and an additional shaft, an adjustable power connection between said secondary shaft and said auxiliary shaft, a universal joint connection between said auxiliary shaft and said additional shaft, and a universal joint connection between said additional shaft and said knife shaft, said auxiliary and additional shafts being normally coaxial with said knife shaft, means for shifting said auxiliary shaft to non-coaxial position while its axis remains parallel to the knife shaft axis, said additional shaft being at an angle to said auxiliary shaft and said knife shaft when said auxiliary shaft is shifted, the two universal joints secured between their respective shafts having the same orientation with respect to each other.

18. An apparatus for successively severing sheets of predetermined length from a continuously moving web, said apparatus comprising a knife mounted on a rotatable shaft, a power source and means connecting said power source and said rotata le shaft, means for varying the average speed 0 rotation of said rotatable shaft, .means for cyclically varying the speed of rotasheets of predetermined length from a continuously moving web, said apparatus comprising a knife mounted ona rotatable shaft, a power source and said rotatable shaft, means for varying the average speed of rotation of said rotatable shaft, means for cyclically varying the speed of rotation of said rotatable shaft, said means comprising a universal joint between said rotatable shaft and a portion of said means connecting the power source thereto, said means for varying the average speed of rotation of the variable shaft and said means for cyclically varying the speed of rotation of said rotatable shaft being inter-related by an additional adjustable means for varying the two means simultaneous- 1y, said last-mentioned additional means comprising a pair of shafts connected together by worm gears by whichthey are locked in selected position.

ALBERT F. SHIELDS.