US2020996A

US2020996A - Cutting mechanism

Info

Publication number: US2020996A
Application number: US676411A
Authority: US
Inventors: Curtis S Crafts
Original assignee: GOSS PRINTING PRESS CO Ltd
Current assignee: GOSS PRINTING PRESS Co; GOSS PRINTING PRESS CO Ltd
Priority date: 1933-06-19
Filing date: 1933-06-19
Publication date: 1935-11-12
Anticipated expiration: 1952-11-12

Description

Nov. 12, 1935. c. s. CRAFTS I CUTTING MECHANISM 5 Sheets-Sheet 1 Filed June 19, 1955 INVENTOR 6'. 5. 07a is.

' ATTORNEY 7 Nov. 12, 1935.

C. S. CRAFTS CUTTING MECHANISM Filed June 19, 1933 5 Sheets-Sheet 2 INVENTOR lll H TTORNEY Nov. 12, 1935.

C. S. CRAFTS CUTTING MECHANISM Filed June 19, 1955 5 Shee't's-Sheet 5 INVENTOR 6'. ,5. Cra

Nov. 12, 1935. c. s. CRAFTS CUTTING MECHANISM 'Filed June 19, 1935 5 Sheets-Sheet 4 INVENTOR 6T Cri'iwfl ATTORNEY Nov. 12, 1935. c', s, CRAFT 2,020,996

CUTTING MECHANISM Filed 'June 19, 1933 5 Sheets-Sheet 5 INVENTOR d 63 %is.

Trolh i Patented Nov. 12, 1935 PATENT OFFICE CUTTING MECHANTSM Curtis S. Crafts, Oak Park, Ill., assignor to Goss Printing Press Company, Chicago, 111., a corporation of Illinois Application June 19, 1933', Serial No, 676,411

18 Claims.

The present invention relates to folding mechanisms and more particularly to a novel and improved shear cutter and folding mechanism for use with printing presses.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instru' mentalities and combinations pointed out in the appendedclaims.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Figure 1 is a vertical section taken on the line il of Figures 2, 3, 4 and 5, with certain parts omitted, and shows an illustrative embodiment of the present invention. In this figure, certain n portions have been broken away, and those portions of the shear-cutter blades lying to the rear of the section plane have been omitted for the sake of clearness;

Figure 2 of the drawings is a fragmentary sec tio-nal view looking to the left of the line 2-2 of v Figure 1 and shows the left-hand cylinder, with certain parts shown in section;

Figure 3 is a similar view, looking to the right of the line 2-2 of Figure 1, and shows the righthand cylinder;

Figure 4 of the drawings is a fragmentary top plan view of the left-hand cylinder of Figure 1, with certain parts shown in section;

Figure 5 of the drawings is a similar view of the right-hand cylinder of Figure 1;

Figures 6 and 7 are diagrammatic side elevations of the right-hand cylinder and web, atthe beginning and at the end of the cutting operation respectively; 7

Figure 3 is a diagrammatic end view of the cutting cylinder and cooperating folding cylinder; and,

Figure 9 is a fragmentary, diagrammatic,- sectional view of the shear-cutter blades, web and sheet during cutting, showing several successive positions of the blades, web and sheet.

The present invention provides a novel and improved shear cutter and cooperating folding mechanism, in which the folding cylinder and cutter blades cooperate in a novel manner to prevent buckling of the adjacent ends of the sheet and web at the line of cut. The invention also provides an improved shear cutter mechanism and method of cutting particularly adapted for cutting paper web into sheets at relatively high 5 speeds. A further object is the provision of a shear cutter in which the adjacent ends of paper at the cut-are gradually moved away from each other and from both the shear cutter blades immediately after the cutting operation thereby 1' preventing interference of the blades and the cut edges of the sheet and web. The invention also provides an improved construction of shear cutter in which the blades may be set in position-easily and with a high degree of precision. 5 Still another object is the provision of a shear cutter-mechanism in which the blades clear each other at any point along the blades immediately after completion of the out at that point.

In, accordance with the illustrative embodi- 2 ment of the invention, the shear cutter comprises a pair of cylinders geared together and provided with cooperating shear cutter blades adapted to cut a web of paper transversely thereof, the cut beginning at one edge of the web and progressing transversely of the web until a sheet is completely severed from the web. As embodied, the leading shear cutter blade projects slightly beyond the pitch circle of its cylinder driving gear, while the following blade is set on the pitch circle of its cylinder driving. gear, so that the cutting edge of the leading blade has a slightly faster peripheralspeed than either the web or the cutting edge of the following blade. The face of the following blade is set to extend rearwardly inwardly from the cylinder radius, while the leading blade is set on an extension of the following blade face at the instant-of cutting at that point. The cylinders, as usual in shear cutters, are rotatably mounted withtheir axes at a slight angle to the horizontal, and the cutter blades are set with their cutting edges lying substantially on a helix generated about their respective cylinder axes, so that the development of the cutting edges on the web to be cut is at right angles to the path of the web. In order to compensate for the slightly faster travel of the cutting edge of the leading blade, the helices are of slightly greater pitch than usual, with thefleading end of each blade atthe upper end of each cylinder set slightly in advance of its true helical position.

The cooperating folding cylinder is provided with sheet taking devices, such as grippers, to take the lead end of the sheet as it is out from the web, and is also provided with the usual folding blades to fold the sheet. Between each sheet taking device or gripper and its immediately following folding blade or knife, the cylinder surface is formed on a spiral of, slightly increasing radius so that the sheet is accelerated slightly immediately after cutting to move its trailing end' away. from the following shear cutter blade by the spiraled surface of the folding cylinder, the acceleration of the sheet being more than sufficient to compensate for the excess in speed of the cut- .ting edges of both blades over web speed, while the leading end of the web (immediately adjacent to the trailing end of the sheet and formed by V the cutting operation) moves relatively away from the cutting edge of the leading blade by reason of the excess speed of the leading blade.

The present embodiment of the invention also includes novel means for accurately positioning v the shear cutter blades to insure that all points on the blade lie at the samedistance from the cylinder axis, and also provide novel means for testing the accurate positioning of the cutting edges so as to facilitate the proper setting of the blades. 7

it will be understood that theforegoing general description and the following detailed description as well, are exemplary and explanatory of the invention but are not restrictive thereof.

Referring now in detail to the illustrative embodiment of the invention as shown in the accom panying drawings, cutting cylinders I U and H are mounted above the folding cylinder 12 and are adapted to sever the web into'successive sheets which are folded and/or collected prior to being delivered. The cutting cylinders l0 and II are preferably of substantially the same size and rotate on axes parallel to each other and inclined slightly transversely of the web,-as is usual with shear cutters.

Each of these cylindersis provided with a pair of shear-cutter blades having substantially helical cutting edges, each blade being adapted to cooperate with its mate on the other cylinder. Each helical blade starts at the high end of its cylinder and continues around and to the other end of the cylinder, so that as the cylinders are rotated withthe web betweenthem, the web is out along the cutter blades H are secured. Cylinder I0 is adapted to rotate in a counter clockwise direction, and the'following side 'ofeach ledge' I6 is so positioned that the following side of blade I! is radial with respect to the cylinder axis. The

following side of each ledge 16 'is .a plane, skew' with respect to the axis of thecylinder, and set at such an angle that the intersectionof the fol 1 lowing edge of blade ll with a cylinder forms the helix required for the cutting edge of the correspondingblade l1. i r 1 Blades I! are preferably formed straight and hat, and are provided with slots-18. through which bolts l9 may be passed to securely fasten the blade to ledge l6. milled down to provide lugs 20 by which the ends of the blade are securely anchored to the body I 5 erence tothe axis of the cylinder.

The ends of blades all are by clamps 2| near the ends of the cylinder;

' Means areprovided for warping the cutting edges ofblades llout of a straight line position after they have been secured to the ledges l6, so

as to bend the cutting edge into the desired helix, and for this purpose there are provided a series ofuniformly spaced screws 22 threaded into, and extending radially of the cylinder body l5'and adapted to push against the rear edge of blade H. 5

At the ends of the blade the cutting edge normally lies on the desired helix, and the intermediate portions of the blade are warped into the helix edge which may be laid on them to extend from 20.

one end of the cylinder to the other. By moving the straight edge circumferentially of the cylinder,the position of all points along the edge of '2 the blade maybe'accurately tested, and the blade may be brought to a true helical shape by moving 25- screws 22 in or out as necessary, after loosening screws [9. i 7 Q V a V The pitch of the helical cutting edges of the blades I1 is such that, takinginto considerationthe inclination of the cylinder axis, the develop-'30 merit of the helix on the surface of the paper web to be cut is substantially at right angles to the feed of the web. In practiceyhowever, and for reasons later explained it is found preferable .to form the ledge surfaces so that the leading ends 35 of the helical blades are very slightly in advance of the true helix, the development of which would be exactly at right angles to the movement of the web.

Means are provided for forming a cylindrical 4() surface on the exte'riorof the cylinder to reduce disturbing air currents, and for this purpose there are provided two substantially semi cylindrical shells 25, extending circumferentially fromone blade IT to the other; and from near one end of 45 the cylinder to'near the other end. These shells may be supportedin any desired manner, but as embodied are supported'on the body portion l5 and are secured thereto by screws 26 cooperating with the dovetailed nuts 21, which are slidable in grooves 28.-

Cylinder l I is of the same general construction as cylinder [0 and is shown atthe left of Figure 1, andin Figures 2 and 4. This cylinder is adapted to rotate oppositely to cylinder l0, and is likewise provided with a pair of shear, cutter blades V 30 ofthe same general construction as those on cylinder [0, and adapted to make cutting contact with blades l7, point-by-point as the'cylinders are rotated in timed relation with each other by gear s'3l. "Shear-cutter blades 30 are mounted on ledges 32 formed integrally with the central portion 33 of cylinder H, and are secured thereto by means of nuts. 34 which clamp the blade against shoulder 38. on bolt 35 threaded into 05 ledge 32. By turning bolt 35 the blade may be raised or lowered on itsledge and may be locked in position by lock nut 39'. The blade support ing surfaces of ledges 32 are also fiat and each extends in a. single plane from near one end, of 7o. I

the cylinder to the other, and are skewwith ref- 'Aswith cylinder [0, a plurality of screws. 3I 2 are positioned against the back edge of the shear! cutter blades and arethreaded into the cylinder 7 As embodied, 15

body, serving to warp 'the cutting edge blade into a true helix with its cutting edge concentric with the cylinder axis, while theends 38 of the blade are held'fast to the cylinder by means of clamps 3'9 which engage the reduced blade ends.

"Gauging means are provided for a facilitating the setting of the blade edge into a true helical .path, and comprise a pair of discs 40 of equal diameter formed integrally with the cylinder near its ends and upon which maybe supported a straight edge for truing the blades as previously described.

Blades30, like blades i! are set with their leading end at the upper end of the cylinder slightly in advance of the true helix, the development of which would lie at rightangles to the web .path, and the advance is the same for the blades on both cylinders, thereby insuring proper cutting contact of the blades throughout their entire length.

As previously described the following faces of blades H on cylinder ll! are preferably radial of cylinder 1'0, and eachpoint of the leading faces of blades 30 on cylinder II is preferably positioned so that each portion of the blade, while cutting, lies on a geometrical projection of the following face of the active blade l1 and radially of cylinder H), as shown in Figure 8.

Means are also provided for forming a substantiallycylindrical surface between the shear-cutterblades 30, and for this purpose substantially semi cylindrical shells 4| are supported on the cylinder body and are secured thereto by means -of bolts 42. When it is desired to vary the setting of the blades 36 or to replace them, these shells may be easily removed affording easy access to the blade mounting and adjusting screws.

.Means are provided for driving cylinders l0 and H at the same angular speed, with shells 25 and '41 at a peripheral speed substantially the same as that of the paper web to be cut into sheets. For this purpose, the discs 23 and 49 at the ends of the-cylinders ill and H support the driving gears 31. At each end, the gears mesh with those of the other cylinder to maintain uniform the angular speeds of the two cylinders as well as to eliminate backlash and maintain the blades in contact while cutting. Suitable means, not shown, may be provided for driving gears 3| at the proper speed with reference to the web. Gears 3| are angularly movable on discs 40 to permit accurate positioning of blades 39 with reference to the blades I! on cylinder 10.

Means are provided for driving the leading blades IT on cylinder l0 slightly faster than the speed of the running web, and for this purpose (see Fig. 8) the cutting edge of the shear-cutter blades I1 on this cylinder projects slightly beyond the pitch circle of its driving gear. Means are also provided for driving the following blades 30 on cylinder ll very slightly faster than the speedof the paper web,and this is accomplished 'by setting the cutting edge of the following blades v30 on the pitch circle of the gears 3| driving cylinder ll.

Thespeed-of the web and sheet, and the speeds of "the cutting edges of blades ll and 3|] in the preferred embodiment are such that, considering the angle of the cylinder axes relative to the line of web feed, the leading blade edge travels faster than the followingblade edge, the following blade edge travels faster than the paper web and .thecut sheet travels faster than the leading blade-edge, so that the leading edge of the web, the cutting edges of blades H and 30 and the trailing edge of the sheet move apart from each other immediately after cutting.

The shear cutting mechanism of the present invention .may be used with many types of folding mechanisms, such as that diagrammatically illustrated in Figure .8. As there shown the folding cylinder I2 comprises a cylindrical body 45, provided with folding blades 46 which areadapted tobe periodically actuated to fold off sheets from the cylinder surface. 41 are provided for gripping the leading ends of the sheets as they are fed to it from the cutting mechanism and the .axis of the folding cylinder is preferably positioned a full sheet length below the cutting cylinder axis, the grippers being timed to close upon and grip the leading end of the sheet immediately prior to the time any cutting of the web W starts. The cylinder surface is preferably formed on a spiral of slightly increasing diameter from each gripper 41 to the following folding blade 46, the diameter at the gripper being sufficient to produce a peripheral speed equal to that of the paper speed. The cylinder surface from the folding blade 46 to the following gripper 41 is preferably cylindrical and of suflicient diameter to produce a peripheral speed slightly in excess of web speed.

Figures 6 and 7 illustrate diagrammatically the angular relationship between the cylinder blades and web path. As shown in these figures, the web is fed vertically downward between the cutting cylinders. Figure 6 represents the righthand cylinder, at the beginning of the. cut, and cylinder l0 rotates about an axis which is displaced slightly from the horizontal. Line 50 indicates the developed projection of the blade on the web W, While line 5| indicates the line along which the web is to be out. The blades H and 30 are so set that the cut begins at the high end of the cylinder and progresses towards the low end of the cylinder to produce a horizontal out, transverse to the line of web feed.

Figure 7 is a similar view showing the parts at the end of thecutting operation, and as will be noted the blade II has gained very slightly on the web, and the portion of the blade first 'to cut the web has moved below thecut 5| and out of the way of the edge of the web immediately behind the cut.

Figure 9 of the-drawings illustrates several successive positions of the shear cutting blades, together with the web, all taken in the same vertical plane, and illustrates the manner in which the blades move away from each-other and from the cut edges of the web.

trailing end of the sheet are indicated by the short double line, while the leading end of the web is indicated by the short heavy line between the twocylinders. It will be noted from a close inspection of these successive lines that the cut edges of the web and sheet are gradually moved apart perpendicularly, due to the faster travel of the sheet and the lateral pushing :apart of Sheet taking means In this figure, the leading blade I! is shown at the right, while the these edges by the blades I1 and 3B. This lateral movement of the sheet end causes the sheet to clear blade 30, due to the inclination of the blade and the faster travel of the sheet, while the web end clears blade I! due to the faster travel of the blade. Inasmuch as the lateral movement of the sheet also causes the cut edges to be moved nearer the cylinder centers, the speed of the blades'is reduced relative to the paper speeds. Furthermore, after position d, the blades are moving away from the line of Web feed slowing the perpendicular travel of blades I land 30. In this way, the blades are constantly moved outof the way of the sheets through positions e, f, g and h and there'is no tendency for the sheets or web to buckle, as has heretoforebeen the case. Due to this avoidance of buckling of the sheets, the leading end of the web has no tendency to go to one side or the other after the blades have moved apart to the position it and the lead end of theweb is easily guided into the guides 48, which extend to a point closely adjacent to the folding cylinderlz. There is also avoided any tendency of the trailing edge of the sheet to be moved to the left by the cutting edge of the following blade 36, as has heretofore been the case, and there is no danger of the trailing end of the sheet being caught on the upper and pointed end of the lefthand guide 48.

The invention in its broader aspects is not limited to the specific mechanisms shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the in- Vention and without sacrificing its chief advantages.

What I claim is .1. A folding and cutting mechanism including in combination a pair of shear cutter cylinders, and a cylinder provided with sheet grippers to take a sheet as it is cut from a web by the shear cutters, a blade on each cutter cylinder, one of said blades travelling faster than web speed, and said gripper cylinder being provided with sheetengaging surfaces which are spiral in cross-section to accelerate the cut sheet immediately after cutting to move the sheet away from said. faster blade.

2. A folding and cutting mechanism including in combination a pair of shear cutter cylinders and a cylinder provided with sheet taking means and folding blades to take a sheet cut from a web by said shear cutters, a blade on each cutter cylinder,

both of said blades travelling slightly faster than web speed and one slightly faster than said other blade, and said gripper cylinder being formed with a spiral surface to accelerate the sheet immediately-after cutting to move it away from the slower blade. j l

3. A shear cutter including in combination a pair of cylinders to rotate together, a shear cutter blade on each cylinder and means for driving the cylinders with the cutting edges of both blades travelling in excess of web speed and the cutting edge of the one blade in excess of the other.

4. A shear cutter including in combination a pair of cylinders to rotate together, a shear cutter blade on each cylinder and a gear coaxial with each of said cylinders for driving the cylinders at substantially web speed, the cutting edge of one blade lying on the pitch circle of one gear while the cutting edge of the other blade projects beyond the pitch circle of its driving gear.

5. A shear cutter including in combination a pair of cylinders of substantially the same size to rotate together, a shear cutter blade on each cylinder and a gear coaxial with each of said cylinders for driving the cylinders at substantially web speed, the cutting edge of the leading blade being set farther from its center .of rotation than the following blade edge is from its center.

6. A shear cutter including in combination a 1 pair of cylinders to rotate together, a shear cut-- ter blade on each cylinder and a gear coaxial with 7 each of said cylinders for driving the, cylinders at substantially web speed, the cutting edges of said blades being set on slightly different radii where- "by one cutting edge moves slightly faster than the other and both move in excess of web speed. r

movable towards'and from the axis and a pair of discs coaxial with the cylinder and at the ends of said cylinder for supporting ablade gauging member. r 1 a 9. A shear cutter cylinder including in combination a rotatable body having blade supporting means thereon, a blade mounted thereon and movable towards and from the axis and a pair of discs coaxial with the cylinder and positioned at either end of the blade, said discs having their peripheries alined with the edge of the blade in proper position. r r i V 10. A shear cutter cylinder including in combination a rotatable bodyhaving bladeisupporting means thereon, a blade mounted thereon and movable towards and from the axis and: a pair of 40 gauge supporting members, one at either end'of the blade for gauging the position of the blade.

l1. Ashear cutter cylinder including in combination a rotatable body having blade supporting means thereon, a helical blade mounted thereon, means for bending the blade toward and from'the cylinder axis and a pair of discs coaxial withsaid cylinder, one disc at either end of the blade, for supporting a blade gauging member.

12. A shear cutter cylinderincluding in combination a rotatable body having blade'supporting means thereon, a helical blade mounted thereon, means for bending the blade toward and from the cylinder axis and a pair of discs coaxial with said cylinder, one disc at either end of the blade, said 'rate, shearing said web progressively across said web at right angles thereto by means of shear cutter blades moving with the web and having the leading blade moving faster than the following blade and accelerating said sheet during cutting to remove it from the cutting means as the leading blade is moved away from the lead end of the web.

14. A shear cutter mechanism for folding machines including in combination a pair of 'ro- 0 tatable supports and substantially helical blades on said supports in shearing relation, each portion of the cutting face of one blade being non-radial with respect to its support, while the cutting face of the other blade lies 0n,an ex- 15. A shear cutter mechanism for folding machines including in combination a pair of rotatable supports and blades on said supports in shearing relation, each portion of the cutting face of one blade being non-radial with respect to its support, while each portion of the cutting face of the other blade lies on an extension of said first cutting face as they come into shearing relation.

16. A shear cutter mechanism for folding machines including in combination a pair of rotatable supports and substantially helical blades on said supports in shearing relation, each portion of the cutting face of one blade being nonradial with respect to its support, and each portion of the cutting face of the other blade being radial with respect to its support.

17. A shear cutter mechanism for folding machines including in combination a pair of rotatable supports and substantially helical blades on said supports in shearing relation, each portion of the cutting face of the following blade being rearwardly inclined with respect to the radius of its support, and the corresponding portion of the leading blade lying on the extension of said face while in shearing relation.

18. In a shear cutter, a support for a removable blade, a blade, and means for mounting the blade on said support including a member threaded into said support and bearing against one face of said blade, a second threaded member coaxial with said first member and clamping said blade to said first member.

CURTIS S. CRAFTS.