US3425607A

US3425607A - Strip feeding and severing machines

Info

Publication number: US3425607A
Application number: US558024A
Authority: US
Inventors: Albert A Sargent
Original assignee: Moore Business Forms Inc
Current assignee: Moore Business Forms Inc
Priority date: 1966-06-16
Filing date: 1966-06-16
Publication date: 1969-02-04
Anticipated expiration: 1986-02-04
Also published as: GB1181443A

Description

Feb. 4, 1969 A. A. SARGENT STRIP FEEDING AND SEVERING MACHINES Sheet Filed June 16, 1966 INVENTOR fllemifl. Sager? ATTORNEYS Feb. 4, 1969 A. A. SARGENT' 3,425,6 0?

STRIP FEEDING AND SEVERING MACHINES Filed June 16, 1966 Sheet 3 015 N I N VEN TOR. 42 be 7 3 A. fiazferzi Feb. 4, 1969 A. A. SARGENT STRIP FEEDING AND SEVERING MACHINES Sheet Filed Ju e 1a, 1966 INVENTOR 'aryerz i M AMewi/Z BY fihzau,

Feb. 4, 1969 Sheet Filed June 16, 1966 INVENTOR.

QNY

Alf TOR/VEVS' Feb. 4, 1969 A. A. SARGENT 3,425,607

STRIP FEEDING AND SEVERING MACHINES Filed June 16, 1966 snee t- J of s I N V EN TOR. A fllfiewi ,4 biyenf BY 93; Chi i aha,

ATTORNEYS United States Patent STRIP FEEDING AND SEVERING MACHINES Albert A. Sargent, Grand Island, N.Y., assignor to Moore Business Forms, Inc., Niagara Falls, N.Y., a corporation of Delaware Filed June 16, 1966, Ser. No. 558,024

U.S. Cl. 225-400 18 Claims Int. Cl. B65h 35/10 ABSTRACT OF THE DISCLOSURE A bursting apparatus is provided with a stack of three rolls comprising top and bottom rolls driven at different speeds and a third intermediate roll assembly disposed between the two driven rolls. The top and bottom rolls include a series of axially spaced rigidly connected discs which are mounted on the respective rolls such that the separated sleeves of the bottom roll are positioned in nonregistered alignment with those of the top roll. The paper Web is fed between the bottom roll and intermediate roll, reversed by means of a deflector member, the successive lead ends fed back between the upper roll and the intermediate roll, and the web snapped against a breaker blade due to the faster rotation of the upper roll with respect to the lower roll.

This invention relates to apparatus for separating continuous webs of business forms or the like into individual units or multi-layer sets by means of differential speed feeding members which are operated to apply an intermittent tension in such a web to sever the web, usually along prepared transverse weakened severance lines.

A variety of such devices, frequently called bursters, has been produced prior to this present invention, among which are those disclosed in the following U.S. Letters Patent: Hageman 2,513,093 granted June 27, 1950; Hageman and Mabon 2,778,424 granted Jan. 22, 1957; and Sargent 3,135,446 granted June 2, 1964; each of which contributed novel and ingenious improvements in this general line of business and printing office machines, but all of which still embodied separate sets or pairs of feed and pull rolls and involved positioning the feeding and delivery points at opposite ends of the installation. This latter condition, in which the separated forms leave the machine from the opposite side from the entering web, is sometimes a disadvantageous factor in crowded ofiices when floor space is at a premium. It also requires the attendant to walk from one side to the other when servicing the machine.

The present invention therefore has for its principal object the provision of a novel and improved burster device of the class described, which is of compact construction, convenient and easy to operate and maintain, and which embodies other advantageous features in connection with both the severing of the web and the feeding of the web into the operative mechanism.

The invention in its preferred embodiments contemplates the provision of a compact and readily portable web or strip burster which, instead of the usual spaced apart pairs of feed and pull rolls, employs a stack or stand of three rolls comprising top and bottom rolls which are driven at different speeds and which are each in the form of a series of axially spaced rigidly connected discs or sleeves but with the separated sleeves of one of the driven rolls positioned out of register with those of the other, and a third intermediate roll assembly disposed between the two driven rolls, but comprising a series of discs or sleeves each preferably mounted for free rotation upon the shaft or axle of the assembly. The number of loose sleeves on the intermediate roll assembly is equal to the sum of the number of the fixed sleeves on the top and bottom driven rolls, and the spaced apart sleeves of the latter rolls are located to be in rolling contact respectively with alternate ones of the intermediate loose sleeves.

Thus there are, in operation, one set of freely turning sleeves or roll sections on the intermediate roll assembly being rotated in operative relation to and at the speed of the in-feed roll, and the other set of freely turning sleeves on the same shaft rotatable in operative relation to and at the speed of the out-feed roll. Therefore, when the out-feed roll is speeded up, there can be attained the same effective separation of a web as in the case of the separate sets of rolls of the earlier devices.

The paper web is fed into the machine between the in-- feed roll and the intermediate roll assembly, then reversed by means of a novel deflector member, the successive lead ends caught and fed back into the bite of the faster outfeed roll and the intermediate roll assembly, and the web snapped against a breaker blade. Thus a form unit of appropriate predetermined length is severed from the web and delivered from the machine.

An important feature of novelty resulting from this arrangement is the ability to regulate the length of the severed forms or sets, by three separate adjustments or combinations thereof: adjusting the position of the reversing web deflector; adjusting the position of the breaker blade or knife; and the control of the relative speeds of rotation of the in-feed and out-feed rolls.

Other objects and features of novelty, including several advantageous provisions in respect to the guiding mechanism by which the web is initially threaded into the device, will be apparent from the following specification when read in connection with the accompanying drawings in which one embodiment of the invention is illustrated by way of example.

In the drawings:

FIGURE 1 is a somewhat diagrammatic view in longitudinal vertical section through a machine embodying the principles of the invention, the parts being in idle or loading position, and certain portions of the machine omitted for the sake of clearness of illustration;

FIGURE 2 is a top plan view on an enlarged scale of the principal portions of the machine;

FIGURE 3 is a fragmentary vertical sectional view with the parts in idle position;

FIGURE 4 is a similar view with the portions of the mechanism in running position;

FIGURE 5 is a fragmentary view in horizontal section of the machine adjacent one end portion of the main web feeding cylinder, and as taken on line 5-5 of FIG- URE 4;

FIGURE 6 is a view in vertical transverse section taken on line 6-6 of FIGURE 4;

FIGURE 7 is a fragmentary vertical transverse sectional view taken on line 77 of FIGURE 4;

FIGURE 8 is a fragmentary vertical sectional view taken on line 88 of FIGURE 1 and showing the drive connection between the reversing vane and the endless chain regulating device; and

FIGURE 9 is a view in perspective of this same connectron.

The machine which is featured in the present drawings as an exemplary embodiment of the invention, is designated generally by the reference numeral 10, and comprises suitable supporting framing which includes the

side frames

11 and 12, the side frame designated 11 being the remote one as viewed in FIGURES 1-5 inclusive. The side frame members may be rigidly connected in spaced relationship by any number of cross connections or tie rods such as those suggested at 13 in FIGURE 1, as well as certain transverse shafts employed in support ing and driving certain operative members of the machine and which will be described in due course. A bottom panel for the device is shown at 14 in FIGURE 1.

The strip burster machine may conveniently be roughly divided into three operative areas or zones, an in-feed zone or subdivision indicated at A; a burster zone shown at B; and a delivery area generally located at C.

The actual burster mechanism B, being of major importance as regards both novelty and utility, will be described first.

Referring more particularly to FIGURES 3, 4 and 6 of the drawings, it will be seen that the three operating rolls employed in severing a web are designated 21, 22 and 23.

The lowermost roll 23 is the slow-speed web-feeding and restraining roll and comprises a unitary tubular roll body having a narrower diameter as at 24 and provided with spaced annular ridges 25 providing fixed rigidly connected discs or sleeves of larger diameter between which and the cooperating intermediate roll assembly the web is seized during operation.

The lower roll body 23 is provided with a drive pulley and is freely mounted for rotation upon the supporting shaft 31 which finds bearings at 32 in the respective

main side frames

11 and 12.

The intermediate roll assembly 22, instead of being of unitary rigid construction as in the case of the lower driven roll 23, is made up of a series of independently rotatable wheels, discs, or sleeves designated 35, these sleeves preferably being separated as by means of washers 36 and held in proper rotatable position upon the shaft 37 by means of the end discs 38 Which are pinned as at 39 to the shaft 37. The shaft 37 is immovably fixed in the

side frame members

11 and 12 as at 40. It may be stated here that the end discs 38 which are rigidly fixed to the fixed shaft 37 also serve the purpose of sup- 2- porting a breaker blade or knife which will be described presently.

It will be noted from an inspection of FIGURES 2 and 6 that there are about twice as many free discs in the intermediate shaft assembly as the-re are rigid wheels or discs which form a part of the lower slow speed driven shaft 23, and the discs 25 of the lower shaft cooperate with alternate free discs 35 on the intermediate assembly in feeding the webs.

The third member of the stand of burster rolls is the top roll 21 and this roll is of very similar construction to the bottom roll 23 but is adapted to be driven at a higher speed regulated in accordance with the necessities of the particular job being done. The spaced ridges or annular disc or sleeve portions of the roll 21 are indicated at and they are arranged to cooperate with the alternate free sleeves 35 of the intermediate set 22 which are not associated with the sleeves 25 of the lower roll 23.

The upper roll 21 is provided with a drive pulley 46 which is aligned with the pulley 30 of the lowermost roll 23. The roll 21 also carries a smaller pulley 48 which serves to transmit driving force to the delivery mechanism C as will be described later. The roll 21 is carried by the transverse shaft 50 which has its ends supported in the

side frames

11 and 12.

With the operative rotary elements of the burster described, it will be well to explain the entire drive of the device. Suitably carried on a sub-frame 52 supported on the bottom panel 14 is an electric motor 53, the shaft 54 of which carries a pulley about which is applied the drive belt 55. The belt 55 is trained around the pulley 30 of the lower driven roll 23 and from there it passes around an idler pulley 56 carried upon a stub shaft 57 which may be adjustable within the framework for regulating the tension in the belt 55. The belt then passes around the pulley 46 of the uppermost driven roll 21 and then returns by way of the

guide pulleys

58 and 59.

It will be readily recognized that the disparity of diameters of the bottom roll pulley 30 and the top roll pulley 46 will cause the upper roll 21 to rotate at a faster rate than the lower roll 23. Of course, the speed ratio may be altered by a suitable selection of

pulleys

30 and 46.

By this time, it will be realized that the paper Web or strip being received between the cooperating ridges or axially separated surfaces 25 of the bottom feed roll 23 and the appropriate discs or sleeves 35 of the intermediate roll assembly 22, can be fed in the direction from right to left as viewed in FIGURES l-S inclusive, and then the web given a return bend and fed back in the opposite direction between the ridges forming the discs or sleeves 45 of the rapidly rotating top roll 21 and the appropriate loose discs or sleeves 35 of the intermediate roll assembly. This of course will tend to rapidly reduce the extent of any loop or bight formed in the web between the points of seizure of the two sets of rolls and when this occurs, the bight of the web is snapped suddenly against the breaker blade shown at 60 and the form section of predetermined length severed from the leading end of the web.

The support for the breaker blade 60 and the means for controlling the reversal of the bight of the web will now be described. The blade 60, as clearly shown in FIG-

URES

3 and 4 of the drawings is of angular configuration and is preferably tapered transversely as suggested at 61 from a point intermediate the width of the machine, the shank portion of the blade being secured as by means of the bolt or screw 63 to the rigidly fixed end discs or sleeves 38 carried by the intermediate shaft 37. The securing of the blade about the fixed discs 38 and its projection from said discs may be varied to afford one means for predetermining the length of the sheets to be severed from the web.

The reversing vane for returning the web toward the burster roll stand is of approximately semi-cylindrical configuration and is indicated at 64 in the drawings. For the purpose of supporting this vane in horizontally adjustable position, a sub-frame 65 is carried between the main

side frame members

11 and 12, said sub-frame forming, together with the vane 64, a basket-like structure including side plates 66, tied together by means of the cross rods 67, and the upper and lower gratings comprising upper and lower series of longitudinally extending transversely spaced guide rods or

tines

68 and 69. As shown at 70 the upper and lower edges of the vane 64 are chamfered and slotted at transversely spaced points to embrace the upper and lower rods or

tines

68 and 69 so that the vane assembly is guided in its adjusting movements by these rods.

The forward lower corners of each of the side members 66 are provided with openings through which the shaft 31 of the lowermost roll member 23 extends and the basket sub-frame is thus pivoted on shaft 31 for manual displacement when the necessity arises as will be described.

As best illustrated in FIGURES 2, 3, 4, 8 and 9 the vane 64 is braced near either end by the pairs of parallel vertically disposed plates 72 and rigidly secured to the outermost of these plates 72 upon both sides of the vane member are the brackets 75, a narrower portion 76 of each of which extends through the slot 77 formed in each of the side plates 66. Depending from the end of each portion 76 is the pin 78 which passes through a link 79 in one of the endless chains 80.

Each of the adjusting chains 80 passes around one of the live sprockets 82 fixed upon the shaft 31 which rotatably supports the feed roll member 23. The opposite loop of the chain 80 passes around the grooved pulleylike guide 83 secured to the lower rear corner of the

basket frame

65 and 84. The element 83 can if desired be rotatably mounted and take the form of a pully or sprocket.

It will now be understood that by the application of a suitable crank to the roll supporting shaft 31 the chains 80 may be moved so as to shift the pins 78 depending from the vane assembly to adjust the assembly along the slot 77 to and from the burster roll stack, in order to regulate the size of the loop or bight and thus the length of form section or sheet to be severed from the web.

In order to obtain better access to the inside portion of the basket frame 65 the frame may be dropped by effecting a swinging movement about the axle 31 so that access may be obtained to the loop in front of the vane in case of jamming. The basket frame is shown in its operative position in the figures of drawing and it will be seen that it is capable of being held in such position by the interfitting of the cross bar 85 in the notches 86 formed in the upper edges of the side plates 66. A slot 87 is formed in the main

side frame members

11 and 12 to accommodate the movement of this look bar. On the other hand, when the bar is removed and the frame 65 swung about the axle 31 in a counterclockwise direction as viewed in FIGURES 1, 3 and 4, the hooks 88 projecting from the upper right-hand corners of the side members 66 will abut the axle 50 of the upper roll member 21 and thus limit the downward swinging movement of the basket.

The details of the in-feed portion A of the device will now be described with particular reference to FIGURES 3, 4 and 5 of the drawings. Fixed to a transversely disposed rock shaft 100 suitably supported in the

side frame members

11 and 12 is a smooth surfaced cylindrical drum 101 about which the incoming web indicated at W will pass into the bursting device.

Above the drum and mounted in suitable bearing supports in the side frames is a shaft 102 which has two sets of cranks extending therefrom, one set of cranks indicated at 104 carrying a roller 105 and the other set of cranks 106 supporting a roller 108, the purposes of which will be explained presently.

Also, for pressing the web W against the smooth surface of the drum 101 and preventing rippling or the exclusion of air pockets which would disturb the rapid feed of the web, there are provided the transversely extending set of brushes 110, these brushes being set in a holder 111 pivotally mounted upon the cross rod 112 carried at the end of the crank arm 114 which is centered upon the axle or shaft 100 as will be explained. A coil spring 115 stretched between the holder 111 and a portion of the crank 114 urges the brushes toward the surface of the drum in operative position. One or more arms 116 are rigid with the brush carrier 111 and are cam operated to throw the brushes out of contact with the drum.

Now the mechanism for actuating these various auxiliary members will be understood as the description proceeds with particular reference to FIGURE 5 of the drawings.

A hand crank 120 is fixed to the shaft 100 and there is pinned to the shaft 100 the sleeve 121 which, by means of the elongated bolts 122 is rigidly bound to the gear 125 just inside of the side frame 11, the slabbed-oif cam element 126, and the stepped cam element 127, which is disposed adjacent the end plate 128 of the drum 101. Thus all of these enumerated elements will rock as a unit whenever the hand crank 120 is thrown from the load position of FIGURE 3 to the running position of FIGURE 4.

Now it would be well to trace the operative connections from the gear 125 through the various camming devices. The gear 125 is practically of double width and approximately one-half of its meshes with the pinion 130, which pinion in turn meshes with the idler gear 131 carried upon the shaft 132. This idler gear 131 meshes with a gear 133 which is rigid with the throw-off cam 135 for the lower low-speed roll assembly 23.

It is to be noted that while the middle common roll assembly 22 occupies a fixed axial position, the upper fast roll assembly 21 is urged downwardly toward operative contact with the common roll member 22 by means of the coil spring 136 and the lower roll assembly 23 is urged upwardly into operative contact with the middle roll section 22 by means of the spring 137, these springs being arranged preferably on the outside of the side frames.

The cam 135 is formed with a depressed cam surface 140 the area 140a of which is somewhat deeper than the remaining portion of the cam surface. Thus, as seen in FIGURE 4, wherein is shown the running position of the parts, the lower roll assembly 23 is allowed to come into running contact with the middle roll assembly 22. However, upon rotation of the cam 135 to the other extremity of the surface 140, the lower roll assembly 23 is urged downwardly to a spaced position with regard to the middle roll 22, as shown in FIGURE 3. This movement is effected during the rocking of the hand crank 120 to and from the extreme position shown.

Now the idler gear 131 is also of double width and not only meshes with the pinion 130 already described but also with the toothed segment 14-5 formed on the arcuate shank of the brush carrying crank 114. These cranks 114, one on each side of the drum 101, are provided with circular openings surrounding the extra width portion of the gear 125 as clearly shown in FIGURE 5 of the drawings.

When the parts are in load position as shown in FIG- URE 3 of the drawings, the web W may be laid around the surface of the drum 101 and tucked beneath the temporary bearing roller and fed over and through the bite of the feed roll member 23 and the common roll 22.

During this time the brush carrying crank member 114 is in an upward position and the brushes are held in a position displaced away from the surface of the drum 101 by contact of the circular portion of the slabbedoff cam member 126 with the controlling arm 116 of the brush carrier 111.

Similarly, the stepped cam member 127 is in a downward idle position as shown in FIGURE 3 which permits the guide roller 108 to occupy a downward position as shown.

Now with the movement of the controlling parts including the handle to running position as shown in FIGURE 4, the cam moves to permit the lower roll member 23 to be brought into operative position with respect to the common roll member 22 to seize the lead end of the web, and at the same time the slabbed-off cam member 126 is rotated so that the flat side 126a thereof is adjacent the arm 116 and permits the arm to swing so as to let the brushes 1110 contact the web on the surface of the drum 101, the two-stepped cam 127 swings up so that the forward corner 127a strikes the corner portion of the flat shank end surface of the crank 106 and causes the roller 108 to rise so that the web is carried first around the roller or shaft 102 and then in the opposite direction around the roller 103 before it passes in the bite of the feed roll set.

At the same time the higher portion 1271; of the cam 127 contacts the shaft 105a of the preliminary holddown roller 105 and displaces it from the surface of the drum.

The construction and operation of the delivery section of the machine indicated at C will be readily understood. The delivery belts are trained around the roller 171 carried upon the shaft 172 upon which is fixed the gear 173 which meshes with the gear 174 on the shaft 175. This shaft also carries a pulley or sprocket 176 about which a drive chain or belt 177 is trained, this belt also being driven by the pulley or sprocket '48 carried by the upper roll member 21 which rotates upon the shaft 50. Thus it will be seen that the same drive from the motor 53 which operates the burster arrangement B drives the delivery belt 70 for discharging the severed sheets along the path indicated at S, onto the belts 170.

In summary, the general operation of the device may be described as follows:

To prepare the machine for threading the web into the 7 burster mechanism, the operator swings the hand crank 120 to the position shown in FIGURE 3 of the drawings. This has four principal eflects. First of all, through the

gearing

125, 130, 131 and 133, the throw-off cam 135 is rotated to a position where the raised portion of the active surface 140, working against the fixed intermediate shaft 37, displaces the feed roll 23 downwardly against the influence of the spring 137, thus opening up the bite between the lower and intermediate feed roll couple. At the same time, through the meshing of the idler gear 131 with the teeth 145 on the shank of the crank arm 114, the brush supporting crank arms are swung to the upward position shown in FIGURE 3, the arm 116 being swung upwardly by means of the slabbed-off cam member 126 so that the brush holder 111 with its brushes 110 are held in an upward out-ofthe-way position. Also, the two-step cam 127 is swung downwardly away from the tension guide rollers 102 and 108 leaving them in open position, and from the preliminary hold-down roller 105, which permits the latter to contact the web and press it lightly against the surface of the drum 101 during threading.

Now when the web W is threaded between the roller 105 and the drum 101 and into the bight of the feed roll couple, the operator swings the hand crank 120 in the opposite direction to the position shown in FIGURE 4 of the drawings. This of course reverses the movement of the gear train leading to the throw-off cam 135 and permits the spring 137 to restore the bottom roll 23 to operative contact with its cooperating discs on the intermediate roll assembly 22. Through a reversal of the previously described connections the brush carrying cranks 114 are swung downwardly to the position shown in FIG- URE 4, the arm 116 being dropped by the slabbed-oif surface 126a of the cam 126 and the brushes 110 brought into contact with the incoming web by means of the spring 115. Similarly, the two-step cam member 127 is brought to a substantially vertical position (FIGURE 4) the edge 127a of the cam contacting the butt of the crank 106 which supports the tension roller 108, thus bringing the rollers 102 and 108 into position to throw the web into a zigzag configuration. Also, the raised portion 1271) contacting the shaft 105a throws the temporary hold-down roller 105 out of contact with the web.

The machine, once started, continues to feed the Web between the feed and restraining couple 2322, throwing a bight into the web within the basket comprised by the vane 64 and the

rods

68 and 69, thus feeding the lead end of the web between the fast pull roll couple 2122. This, of course, snaps the bight against the blade 60 and, the various adjustments having been made accordingly, the blade severs the form or sheet unit at the transverse score lines or perforations, and then the separated sheets S are ejected onto the delivery conveyor C and thence to any suitable stacking station.

Thus there has been provided by the present invention a unique burster machine in which the threading of the web and the removal of the forms are both accomplished from the same side, and there is created a convenient and compact device which is of approximately the same size and weight as other associated office accessory equipment, and in harmony with such allied devices.

It is understood that various changes and modifications may be made in the embodiments illustrated and described herein without departing from the scope of the invention as defined by the following claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A device for successively severing sheet units from a web or strip of paper or the like passing therethrough comprising, in combination, a supporting frame; a common back-up roll member supported transversely of said frame and having two independent web-contacting portions thereon; a feed roll member also supported transversely of the frame parallel with said first named roll member and having web contacting portions disposable in web-seizing relationship with one of the web-contacting portions of said common back-up roll member; a pull roll member supported transversely of said frame parallel with said first and second named roll members and having web-contacting portions adapted to be disposed in web-seizing relation with the other of said web-contacting portions of said common back-up roll member; means for guiding the lead end of said web from between the feed roll member and the common back-up roll member to introduce it between the pull roll member and said common back-up roll member; and means for rotating said pull roll member at a faster rate than the feed roll member, whereby the successive lead end portions of the web are severed therefrom.

2. A device for successively severing sheet units from a web or strip of paper or the like passing therethrough comprising, in combination, a supporting frame; a common back-up roll member supported transversely of said frame and comprising an axially extending series of annular independently and freely rotatable web-contacting roll sections; a feed roll member of integral construction supported transversely of said frame and parallel with said ifirst named roll member and having an axially aligned series of spaced circular ridges thereon, and disposable in web-seizing relationship with said first named roll member, the ridges of said feed roll member adapted to register with certain of said rotatable roll sections of the first named roll member; a pull roll member of in tegral construction supported transversely of said frame and parallel to said first and second named roll members and having an axially aligned series of spaced circular ridges thereon, and adapted to be disposed in web-seizing relation with said first named roll member during operation of the device, the ridges of said pull roll member registering with certain other of the freely rotatable roll sections of the first named back-up roll member; means for guiding the successive lead ends of the Web fed from between the feed roll member and the common back-up roll member to form a bight in the web and introduce said ends between the pull roll member and the common back-up roll member; and means for driving said pull roll member at a faster rate than said feed roll member, whereby the successive lead end portions of the web are severed therefrom.

3. The device as set forth in claim 2 in which a burster blade is disposed between the out-feed side of the feed roll and the in-feed side of the pull roll, and within the area of formation of the bight in the web, whereby the action of the pull roll will bring the bight of the Web into tearing contact with said blade.

4. The device as set forth in claim 3 in which means are provided for adjusting the position of the guiding means in accordance with the length of the sheet unit to be severed.

5. The device as set forth in claim 3 in which means are provided for adjusting the position of the burster blade in accordance with the length of the sheet unit to be severed.

6. The device as set forth in claim 3 in which means are provided for predetermining the speed ratio of said feed and said pull roll members in accordance with the length of the sheet unit to be severed.

7. The device as set forth in claim 2 in which the three roll members are disposed in substantially vertical alignment and said guiding means for returning the lead ends of the web to the action of the pull roll comprises an arcuate vane mounted for horizontal sliding movement relatively to the substantially vertical plane of the roll axes.

8. The device as set forth in claim 2 in which the three roll members are disposed in substantially vertical alignment and said guiding means for returning the lead ends of the web to the action of the pull roll comprises upper and lower series of horizontal guide rods and a substantially semi-cylindrical vane mounted for horizontal sliding movement along said rods relatively to the substantially vertical plane of the roll axes.

9. The device as set forth in claim 8 in which said guiding means, including the guide rods and vane, forming a basket device for confining the bight of the web, is supported for unitary swinging movement about a horizontal axis for positioning it for better access to the interior, and limiting means are provided for retaining the basket device in either of its extreme positions.

10. The device as set forth in claim 8 in which a substantially horizontally disposed endless chain is carried on sprockets supported within said frame, a lug extends from said vane to operative contact with said chain, and means are provided for manually rotating one of said sprockets to adjust the position of said vane.

11. The device as set forth in claim 10 in which the lowermost roll member is carried by an axle, the manually rotatable sprocket is fixedly carried by said axle, and means are provided for manually rotating said axle to eflect the adjustment of the position of said vane.

12. The device as set forth in claim 11 in which said guiding means, including the guide rods and vane, forming a basket device for confining the bight of the web, is supported for unitary swinging movement about said axle for positioning the guiding means for better access to the interior.

13. The device as set forth in claim 3 in which certain transversely spaced portions of said first named back-up roll member are disposed in fixedly nonrotatable positions and means are provided for adjustably securing said burster blade to said fixed portions.

14. The device as set forth in claim 2 in which there are provided in-feed mechanism for guiding the web into the seizure of the feed roll member and the back-up roll member, and means for displacing said feed roll member from operative position with respect to said back-11p roll member during threading-up of the Web.

15. The device as set forth in claim 14 in which there are provided means for manually throwing said in-feed mechanism into and out of operative condition for threading-up, and means for automatically actuating the burster feed roll mechanism displacing means when the in-feed mechanism is thrown out of operation.

16. The device as set forth in claim 14 in which in-feed means are provided which comprise a smooth curved arcuate surface on the approach side of the burster, yielding flexible means movable to and from a position to gently press the incoming web against said arcuate surface, manual means for moving said pressing means to and from operative position, means connected with said manual means for throwing the feed rolls of the burster into and out of operation coincidentally with the moving of the pressing means into and out of operation, whereby the infeed means and the burster rolls may be substantially cleared for threading of the web prior to operation.

17. The device as set forth in claim 14 in which in-feed means are provided which comprises a smooth curved arcuate surface on the approach side of the burster, temporary holding means comprising a pressure roll yieldably bearing on said web against said arcuate surface to aid in threading the web, manually operable means for simultaneously throwing said pressure roll into operative position and the feed r011 couple of the burster out of operative position, and vice versa.

18. The device as set forth in claim 1.4 in which in-feed means are provided which comprises a smooth curved arcuate surface on the approach side of the burster, a pair of tension guiding rollers about which the web is adapted to be fed in passing to the burster means, means for moving said tension guiding rollers from web threading position wherein the web may pass freely by them with minimum contact, to a position diverting the path of the web from a substantially straight line to a zigzag configuration, means operated by said manual means for simultaneously throwing said burster rolls into operative position when the tension rolls are moved to their operative position.

References Cited UNITED STATES PATENTS 2,862,554 12/1958 Davidson et a1. 225- 3,161,335 12/1964 Pine et al. 225-100 JAMES M. MEISTER, Primary Examiner.