WO1993004967A1

WO1993004967A1 - Timed splicing method and apparatus

Info

Publication number: WO1993004967A1
Application number: PCT/US1992/007623
Authority: WO
Original assignee: Butler Automatic, Inc.
Priority date: 1991-09-04
Filing date: 1992-09-04
Publication date: 1993-03-18

Abstract

A method of splicing a first web drawn from a running roll (26) and feeding at a selected line speed to the leading edge margin of a second web on a ready roll (28), which margin is releasably attached to the periphery of that roll and carries an adhesive (T). According to the method, the angular velocity of one of the rolls is controlled to obtain a speed match between the first web and the ready roll periphery and the instantaneous angular position of the edge margin is determined. Then, the first web is pressed against the ready roll periphery to form a nip at a time when the edge margin is at a selected phase angle ahead of the nip. Upon obtaining the speed match, the ready roll is accelerated to advance the edge margin through the nip to effect the splice between the two webs, after which the first web is severed behind the splice.

Description

DESCRIPTION "TIMED SPLICING METHOD AND APPARATUS" TECHNICAL FIELD 5 Accordingly, the present invention aims to provide a splicer which can make good splices between a ready web and a running web over a wide range of web speeds between a speed somewhat greater than line speed and zero speed.

Another object of the invention is to provide a splicer 10 such as this which can make a splice in a minimum amount of time so that a minimum amount of web storage is required to meet the web needs of a downstream web consuming machine.

Another object of the invention is to provide a splicer which can achieve a good speed match between the two webs 15 being spliced prior to the splice.

Still another object of the invention is to provide a speed match splicer which can splice an unwinding web to the leading end of a web at a ready roll periphery at a speed substantially less than the line speed of a downstream high

20 speed web consuming machine.

Yet another object of the invention is to provide a splicer which, while achieving a speed match between webs, can also be replenishing web in an associated web accumulator. 25 A further object of the invention is to provide a speed match splicer for splicing at less than line speed which can accelerate a running web and a ready web after a speed match independently of the location of the leading end of the ready web. 30 The present invention also aims to provide a splicer which maximizes the time that the running and ready webs being spliced are in contact prior to the actual paste.

_* Still another object of the invention is to provide a splicer which can splice webs so that the spliced tail has

_* 35 any selected length.

Yet another object of the invention is to provide a method of splicing webs together in a very precise manner so that the time of contact of the two webs prior to the paste is maximized resulting in precise speed match at the time of the paste.

Still another object of the invention is to provide a method of splicing a running web to a ready web which produces one or more of the above advantages.

The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others and the apparatus embodying the features of construction, combination of elements, and arrangement of parts which are adapted to effect such steps, all as exemplified in the following detailed description, and the scope of the invention will be indicated in the claims. Briefly, the splicer of this invention is a turret splicer similar to the one disclosed in my copending application Serial No. 695,705, filed May 3, 1991, the contents of which is hereby incorporated by reference herein. It should be understood, however, that aspects of the invention also have application to other known types of speed match and zero speed splicers. The present splicer supports web rolls on roll chucks at opposite first and second ends of the splicer turret. The turret can be rotated to position the chucks at each end of the turret at a roll loading position close to the floor, the chucks at the opposite end of the turret then being in a roll running position elevated above the floor. When a web roll is in its elevated running position, web from that roll is conducted past a splicer head and through a web accumulator to a downstream web-consuming machine such as a printing press. While web is being withdrawn from that roll at a selected speed which may be line speed on a speed greater or less than line speed, the leading edge of the web on a ready roll may be prepared by squaring off that edge and "tacking" it to the underlying web convolution on that roll. Also, a strip of double-faced adhesive tape or contact adhesive spots may be applied to the leading edge margin of that web. Prior to the expiration of the running roll, the ready roll, prepared as aforesaid, is engaged by the chucks at the second end of the turret.

When the running roll reaches a selected minimum diameter, a splice cycle is initiated which results in the leading end of the web on the ready roll being pasted to the trailing end of the web from the running roll so that the web consuming machine now draws its web requirements from the ready roll. This process is repeated when the roll at the second end of the turret, now the running roll, has unwound to a selected diameter. The turret is again rotated to position the first end of the turret at its loading position, the empty roll core is removed from the chucks at that end and a new roll is prepared and loaded onto the first end of the splicer to await depletion of the web from the running roll at the second end of the turret, at which point another splicing operation takes place. This process is repeated so that web can proceed uninterruptedly to the web consuming machine.

If the speed of the running web is reduced in order to effect the splice between the two webs at a speed less than line speed, the web stored in the accumulator can be drawn down to supply the needs of the web consuming-machine so that a substantially constant line speed can be maintained. The accumulator is also sensitive to changes in the tension of the web and, therefore, it is normally used to provide control signals for braking the running web roll so as to minimize tension upsets, as is well known in the art. In accordance with this invention, during the splice sequence described above, if the splice is to occur at a speed other than zero speed, prior to making the actual paste of the webs, the ready roll is accelerated so that its surface speed reaches a selected fixed speed which may be line speed or a selected splicing speed greater or less than line speed. In this connection, the splicer includes means for measuring the diameter of the ready roll, as well as means for monitoring the angular velocity and phase of that roll so that the surface speed of the ready roll can be determined precisely prior to the splice. Further, if splicing is to occur at a speed less than line speed, the running roll is braked so as to slow the running web so that it reaches the splicing speed at about the same time the ready roll surface.

By the same token, if splicing is to occur at a speed greater than line speed, the running web is accelerated to match the surface of the ready roll. In all cases, however, the speed of the running web is controlled or fine-tuned to match the surface speed of the ready roll, instead of vice versa as has been done heretofore. This allows a very fast and accurate speed match to be attained.

The splicer also includes a sensor for monitoring the splicing tape or other marking on the ready roll surface. The outputs from that sensor and the encoder means monitoring the rotation of the ready roll are applied to the splicer controller which tracks the location of the splicing tape on that roll. Using those inputs, the controller controls pressing means such as a brush or nip roller so as to press the running web against the surface of the rotating ready roll to form a nip when the adherent leading edge margin of the web on the ready roll is at a selected phase angle relative to the nip, e.g. 40° to 350° and most preferably immediately after the splicing tape on the ready roll has been rotated past the splicing location opposite the running web. Thus, most preferably, prior to the paste, the two contacting webs will have almost a complete revolution of the ready roll within which to achieve a good speed match. Also, provision may be made for actuating the pressing means in anticipation of speed match to account for the inertia of the pressing means, again, to optimize the splice and minimize the length of the splice cycle.

It is important to note that if the splicer is splicing at a speed less than line speed, as soon as the speed of both webs is matched as aforesaid, both webs are accelerated up to line speed. It is not necessary to wait until the paste of the two webs actually takes place at some time during the next full revolution of the ready roll. In other words, after a speed match is indicated, the webs may be accelerated independently of the location of the adherent leading edge margin of the ready web and whether or not the paste has occurred. This minimizes the length of time that the running web remains at the slower splicing speed and thus minimizes the amount of web storage required for splicing at any given speed.

Immediately following actuation of the pressing means, the controller, in response to signals from the encoder means, actuates a knife to sever the running web just behind the splice thereby separating the webs from the depleted running roll core so that web is now drawn from the ready roll. Provision is made for adjusting the time of knife actuation after the paste so that the length of the splice tail may be adjusted, although a minimum tail is usually preferred.

After splicing at a speed less than line speed, acceleration of the ready roll continues until the web reaches line speed or a speed greater or less than line speed. A speed greater than line speed may be desired in order to refill the accumulator with web following a splice cycle; a speed less than line speed may be chosen in order to decrease the amount of web in the accumulator following a splice cycle, e.g. to prepare for an emergency stop situation which necessitates stoppage of the web consuming machine, i.e. zero line speed.

In a splicer, the web accumulator provides a supplementary source of web to supply the needs of the web consuming machine during splicing as described above. This assumes that at the beginning of the splice cycle there is plenty of web storage in the accumulator. In some cases, this may not be the case due to web depletion during a prior splice cycle. To compensate for this, at the beginning of the splice cycle, the ready roll may be accelerated to a fixed speed slightly faster than line speed and the running web also accelerated to that speed and fine-tuned speedwise to achieve a speed match. This means that during the splice cycle, the accumulator is being filled with, rather than being emptied of, web.

The present splicer can also be used to splice at zero speed. In this case, after the ready roll is loaded onto the splicer, it is rotated to position the splicing tape almost a full revolution ahead of the splicing location, e.g. 350°, the outputs of the tape sensor and ready roll encoder being used by the controller to so position that roll. The ready roll is braked at that location until the running roll is about to expire, at which point the splice sequence is commenced.

When splicing at zero speed, there is no substantial acceleration of the ready roll; the running roll is braked to a stop. As soon as that occurs, i.e. a "speed match", the splicer controller actuates the pressing means to press together the two webs as was done in the speed match mode of operation described above. Immediately thereafter and before the actual paste of the webs has even occurred, the splicer controller initiates acceleration of the ready roll and running web. The two webs become pasted together as soon as the splicing tape is rotated into the nip between the running web and the ready roll.

In the meantime, when the ready roll began rotating, the ready roll encoder began issuing signals to the controller. The controller uses these signals and the known location of the splicing tape at the outset to track the location of the tape. As soon as that tape next passes through the nip between the running web and the ready roll, the controller actuates the knife to sever the running web from the depleted running roll core. Since the web is moving when the knife is fired, the splicer can achieve a clean cut of even heavy webs because it is easier to cut a moving web than a stationary one.

Web continues to be drawn from the ready roll at an increasing rate until a speed equal to the line speed or a speed greater or less than line speed is reached depending upon whether web is to be added to or taken from the accumulator. When operating in the zero speed splicing mode, then, the splicer still minimizes the time that the running web remains at zero speed thus minimizing the time, and the amount of web storage, required to make each splice.

This splicer is thus advantaged in that it can splice webs at zero speed, at line speed or at a selected speed greater or less than line speed. The splicer achieves a speed match quickly and reliably and thus minimizes the amount of time and the amount of web storage required to make a splice at a given splicing speed. The splicer also has other features which will be described in more detail later that combine to optimize the splicing procedure.

BACKGROUND ART

The providing of an uninterrupted supply to web is important in many industries, particularly in the printing industry. Today's high speed printing presses print on web, i.e. paper, cloth, etc., drawn from a roll rotatably supported by a roll stand located upstream of the press. In order to avoid having to shut down the press each time a web roll expires, a splicing mechanism is invariably incorporated into the roll stand to enable the trailing end of the expiring web to be spliced to the leading end of the web on a new roll.

Modern day presses can turn at very high speeds and thus they consume web at a high rate, e.g. in excess of 2000 feet per minute (fpm) . Consequently, in order for the printing operation to proceed with maximum efficiency, it is essential that the splicing of one web to another occur in a minimum amount of time and with a minimum wastage of web.-

Actual splicing of one web to another can be accomplished at line speed, i.e. the speed of the press or other web consuming machine, or at some lesser speed including zero speed. In the former case, prior to making a splice, the ready or fresh roll, which is usually supported on a rotatable turret, is accelerated so that its surface speed substantially matches the speed of the running web. In the usual zero speed splicer, the new or ready roll remains stationary and the running web is decelerated to zero speed or to some relatively slow speed greater than zero in anticipation of the splice. Just before the running roll expires, the splice is made between the trailing end of the running web and the leading end of the web on the ready roll. Then, the ready roll is accelerated up to line speed. During this splicing sequence when the running web roll is slowed or stopped, the web consuming machine draws web from a web store such as a festoon or accumulator located between the splicer and the web consuming machine. That web accumulator is refilled with web following each splicing operation.

In both types of splicer, prior to each splicing operation, the leading edge of the web on the ready roll must be prepared for the splice. In the case of a speed match splicer which splices with the webs being at a speed other than zero, such preparation involves squaring off the leading edge of the web on the ready roll and temporarily tacking that edge to the underlying web convolution on the roll by means of short adhesive strips spaced along the leading edge of the web and oriented perpendicular thereto. The tacking of the leading edge to the remainder of the roll can also be accomplished with appropriate releasing adhesive spots applied to the undersurface of the leading edge margin of the web.

The splice preparation procedure invariably also involves the application of a double faced adhesive strip to the leading edge margin of the web on the ready roll. The adhesive strip may be a single straight strip which extends across the full width of the ready web or it may be a strip , which follows a zigzag or sinuous course across the web. In any event, that adhesive strip presents a sticky or tacky ■, 5 surface to the running web. In lieu of that strip, adhesive spots may be applied to the web margin. In the typical speed match splicer, the actual splice is effected by momentarily pressing the running web against the surface of the ready roll at the adhesive strip thereon after that roll has been

10 accelerated up to speed as noted above. The two webs become adhered together or spliced as soon as the adhesive strip or the adhesive spots are rotated into engagement with the running web. Immediately thereafter, a knife is actuated to sever the running web just behind the splice thereby

15 separating the running web from its expiring roll core, leaving the ready roll to supply the continuing needs of the web consuming machine.

Splice preparation for a zero speed splicer is somewhat different in that the leading edge of the web from the ready

20 roll, squared off and faced with an adhesive strip or coated with adhesive spots, is tacked to a splice preparation bar or roll of the splicer instead of to the ready roll. Prior to decelerating the running web before the splice, the web preparation bar or roll, with the prepared leading edge of

25 the ready web attached to it, is moved into a splicing position facing the running web. After the running web has been decelerated to zero speed, the preparation bar or roll is moved momentarily against the running web so that the two webs are pressed together making the splice. Immediately

30 thereafter, the running web is severed just behind the splice and the ready roll is accelerated until the web drawn therefrom is at line speed and the web store is replenished.

While the above-described prior splicers have operated

T satisfactorily at reasonably high press speeds, i.e. up to

35 2000 fpm, as those speeds become even higher, certain problems manifest themselves. In the line speed splicer, for example, the acceleration of the ready web roll up to the full speed of the running web produces substantial windage at the surface of the roll. This tends to lift up the leading edge of the web from the roll, despite the fact that that edge is tacked to the roll as noted above. Resultantly, when the running web is pressed against that leading edge to effect a splice, the splice between the two webs may be wrinkled or otherwise defective. Such inferior and defective splices can cause downstream tension upsets and web breakage. On the other hand, a zero speed splicer serving a high speed press requires a large capacity web accumulator to supply the web needed by the press while splicing takes place. Accordingly, the splicer takes up a large amount of floor space. Also, the accumulator incorporates a large dancer assembly and large rollers which have high inertias so that the accumulator cannot respond quickly enough to compensate for some tension upsets as it is supposed to do.

To address the above problems, a third type of splicer has been developed which is really a hybrid in that it has characteristics of a speed match splicer and also of a zero speed splicer. This splicer which is described in my application Serial No. 695,705, filed May 3, 1991, is basically a turret splicer of the speed match type so that the leading edge of the ready web is prepared against the ready roll. However, the splice is made after the running web has been decelerated to a selected splicing speed and the ready roll has been accelerated so that its surface speed matches that of the running web. Thus, by splicing at a speed between zero and line speed, that splicer can, for example, avoid the windage problem noted above and can also incorporate a smaller accumulator because less web is used up during the splicing sequence. That hybrid splicing apparatus appears to be an attractive option as press speeds approaching 3000 fpm. It has other advantages as well which are detailed in that application. The present invention is particularly applicable to splicing apparatus of that hybrid type.

One big problem with speed match splicers is that for a good splice to take place between the running web and the ready web, the relative speed of the two webs should be zero at the time they are joined by the pressure sensitive adhesive applied to the leading end of the ready web during the web preparation procedure. Invariably, however, there are variations in the speeds of the two webs due to eccentricities in the web rolls, irregularities in the webs, small variations in the mechanisms and electronics controlling the speeds of the two webs, etc.

The prior splicers try to compensate for this speed mismatch by controlling the angular velocity of the ready roll. However, in the splicers servicing today's high speed presses, the fresh web rolls are quite large and heavy, e.g. 4 feet or more in diameter, 5000 or more pounds, and, therefore, have large angular moments of inertia. Accordingly, it is quite difficult if not impossible to achieve an exact speed match by controlling the rotation of the ready roll. Even small speed variations can result in a splice having gaps or wrinkles which can cause tension upsets, jams and other problems in the press downstream from the splicer, resulting in economic loss due to web wastage and press downtime. One way to improve the speed match between the ready web and the running web is to bring the two webs into contact with one another before the actual paste is made. In other words, the two webs may be brought together at a time when the adhesive strip or the line of adhesive spots on the leading edge of the ready web is angularly displaced from the splicing location, i.e. the nip of the two webs. During this initial web contact period, the speeds of the two webs will tend to equalize. Clearly, the longer the two webs are in intimate contact, the more likely it is that the speed difference between the webs will be zero at the instant of the paste. Thus, in a splicer in which the leading edge of the ready web is prepared on the ready roll itself, it would be desirable if the two webs could be brought together just after the adhesive strip on the leading edge of the ready web has rotated past the splicing location. This would allow the two webs to remain in contact for the time it takes the ready roll to rotate almost a full revolution to bring the adhesive strip on the ready roll opposite the running web at the splicing location a second time. However, this optimum condition is difficult to achieve precisely if the speed match is sought by controlling the rotation of the large heavy ready roll whose weight varies depending on the diameter of the roll.

Also, a splicer which splices the two webs when the running web is traveling at a selected speed less than line speed still requires a relatively large amount of web storage. This is because of the random location of the splice tape at the instant contact is made between the two webs and the need to wait until the tape has been rotated into contact with the running web before being able to accelerate the ready roll up to press speed. In fact, the webs should be brought together as soon as possible after the running web has reached the selected splicing speed in order to minimize the amount of web storage given up by the web accumulator while the expiring web is at the splicing speed because, at that speed, the rate of web depletion is at a maximum. As noted above, in many applications, it is desirable to minimize the required size of the web store because that minimizes the overall footprint of the splicer. Further, in any splicer, whether it splices at line speed or at some slower speed, the solenoids, air cylinders, valves, motors and other devices which carry out the various functions required for splicing are controlled by timed signals from the splicer controller. Those parts also have their own built-in inertias. Thus, when the splicing tape or other marking on the surface of the ready roll is used to initiate contact between a ready web and a running web at the time of splice, a finite amount of time will pass between the detection of the tape or marking and the movements of the ♦ brush, roller or other means that actually bring the two webs into contact. For example, in a typical splicer, prior to . 5 the actual splice, the ready roll may be turning at 4 revolutions per second, each revolution taking 0.250 ms. If it takes 0.150 ms after detection of the usual splice marking to bring the two webs into intimate contact, this leaves only 0.100 ms to achieve a speed match between the two webs, i.e.

10 zero relative speed. It would be desirable, therefore, to be able to control the splicer so that the running and ready webs are assuredly in contact for the longest possible time prior to the splice, i.e. for almost the full 0.250 ms in the above example.

15 Also, it should be understood that some of the signals which are used to initiate or control the operation of the splicer at the time of splicing may depend upon variables such as line speed, roll diameter which affect the timing of those signals. For example, if a splice marking on the ready

20 roll is detected and used to initiate a splice of the ready web to a running web, the frequency of the detected signal at speed match will vary depending upon the line speed. On the other hand, if the ready roll is rotating at a selected angular velocity, the frequency of the detected signal will

25 vary depending upon the diameter of the roll.

Similarly, in a splicer in which the running web is decelerated to a selected splicing speed prior to the splice, the time it takes for the running web to reach the selected splicing speed will depend upon line speed as well as the

30 amount of web remaining on the running roll. Therefore, it is difficult to optimize the timing of the deceleration signal so that the running web will be reaching the selected splicing speed at the same time as the ready roll surface such that the time of contact between the two webs is 35 maximized in order to achieve speed trim and speed match prior to the actual paste. Resultantly, an excess amount of web storage is used up during the splicing procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevational view with parts broken away showing a turret splicer embodying my invention with the splicer turret shown in its normal running position.

FIG. 2 is a similar view of the splicer showing the turret in its splicing position.

FIG. 3 is a sectional view on a much larger scale taken along line 3-3 of FIG. 2.

FIG. 4 is a fragmentary elevational view with parts broken away of the splicer head in the FIG. 1 splicer when making a splice.

FIG. 5 is a block diagram of the controller in the FIG. 1 splicer showing its various input and output signals.

FIG. 6 is a block diagram of a functional circuit in the splicer controller. DISCLOSURE OF THE INVENTION

Refer now to FIG. 1 of the drawings which shows the splicer generally at 10. The splicer includes an upstanding support 12 which supports a turret 14 which is pivotally connected to the upper end of the support by a journaled axle 16. The turret may be rotated by a motor 18 between a normal running position shown in FIG. 1 wherein the turret is more or less vertical and a splicing position shown in FIG. 2 wherein the turret is generally horizontal. A pair of carriages 22 are mounted to the opposite ends of turret 14. Each carriage carries a pair of chucks 24 for supporting the opposite ends of a roll of web. Thus, the upper chucks 24 in FIG. 1 support a web roll 26, denominated the running roll, whereas the lower chucks 24 in that figure are shown as supporting a roll 28, denominated the ready roll. Actually, a full roll 28 should not be present at the lower turret position in FIG. 1; it is shown to enable an orderly description. The chucks at that position would normally carry a depleted roll core from a previous splicing cycle of the splicer.

The angular velocity of the web rolls at both roll s locations may be controlled by brakes 32 coupled to the associated roll chucks. Since the splicer achieves speed 5 match by controlling the speed of the running roll as will be described, pneumatic brakes with fast response pneumatic servo valves in close proximity to the brakes may be used. These have a much faster response than the DC drives and variable frequency drives used in prior splicers which speed

10 match by controlledly driving the ready roll.

Web W drawn from the running roll 26 is conducted past a splicing head 36 and under a idler roller 38 to a more or less conventional web accumulator 42 which stores a supply of web and contributes to web tension control as is well

15 known in the art. Web from accumulator 42 is conducted to a press or other web consuming machine (not shown) which usually consumes web at a selected fixed rate. The speed of the web W drawn from the roll 26 may be monitored by suitable means such as a tachometer 44 operatively coupled to idler

20 roller 38 as shown in FIG. 2.

As will be described in more detail later, in some cases it may be desirable to accelerate the running web W downstream from head 36. Accordingly, a motorized drive roller 45 may be provided opposite roller 38, with web W

25 passing through the nip of the two rollers. Actually, rollers 38 and 45 would normally be arranged relative to the web path to provide a greater web wrap around the rollers to minimize slippage. Accelerating the running web by a downstream accelerator roll is preferable to doing that using

30 D.C. drives coupled to the running roll chucks in the manner of some prior splicers.

While web is being drawn from roll 26, the ready roll 28 (shown already loaded) is prepared by squaring off the

_* leading edge 28a of the web on that roll and tacking that

35 edge to the underlying roll convolution using conventional tape strips or adhesive spots (not shown) . Also, a strip of double faced tape T is applied to that leading edge margin as part of the preparation procedure. Each turret carriage 22 carries a detector 46 which detects the passage by the sensor of the tape T or some other peripheral marking on the web roll supported by that carriage. The outputs of the detectors as well as of tachometer 44 are applied to a controller 47 which controls all aspects of the splicer and, in the illustrated apparatus, is mounted to accumulator 42.

At some point when the roll 26 nears depletion, turret

14 is rotated by motor 32 to its splicing position shown in FIG. 2. This positions the lower chucks 24 on the splicer turret close to the floor. This is the position at which roll 28 is actually engaged by those chucks and at this position, roll 28 is disposed between a pair of accelerators 52. Each accelerator, described in detail in the above-identified application, includes a conical driver 52a which is rotated by a motor 52b. The accelerators, or at least their drivers 52a, can be moved into and out of engagement with the opposite ends of roll 28. Thus roll 28 can be rotated by engaging and rotating the drivers.

In accordance with the invention, means are provided for monitoring the rotation of a ready roll at both positions on the turret, i.e. the angular velocity and phase of that roll. This may be done by shaft encoders coupled to the chucks 24. More preferably, however, this is accomplished by means of an encoder 54 which monitors the rotation of one or each of the accelerator drivers 52a. This is because it takes about five revolutions of the driver 52a to rotate the ready roll 28 through one revolution. Therefore, encoder 54 has five times the resolution of a similar encoder mounted directly to the roll chucks 24.

Referring to FIGS. 1 to 3, splicer head 36 normally reposes in a retracted position shown in FIG. 1 wherein it is spaced away from turret 14. When turret 14 is in its splicing position as shown in FIG. 2, the splicing head 36 may be moved on rails 54 to an advanced position shown in FIG. 2 wherein it is located close by the periphery of ready roll 28. Idler rollers 56 are mounted to opposite ends of turret 14. Additional idler rollers 58 are mounted between the side plates 36a of the splicer head at the forward corners thereof to guide web W so that a vertical stretch of that web between rollers 58 is closely spaced from the periphery of roll 28 when the splicer head 36 is in its advanced position shown in FIG. 2. Any suitable means may be provided to move splicer head

36 between its retracted and advanced positions. For example, as best seen in FIG. 4, the rails 54 may be formed as racks and the splicer head may be fitted with rotary pinions 62 which engage the racks and are moved therealong by suitable means such as gear motors 62a.

Since the ready roll 28 may have various diameters, the splicer head 36 may have to travel various distances along rails 58 from its retracted or home position shown in FIG. 1 to reach its advanced position depicted in FIG. 2. To determine the advanced position of the splicer head for a particular roll 28, an optical detector 66 is mounted to the splicer head beyond the ends of roll 28. The detector comprises a light source and a light sensor positioned on the splicer head beyond the opposite ends of roll 28 and arranged to sight along that roll. The splicer head is moved from its retracted position shown in FIG. 1 to its advanced position shown in FIG. 2 until the periphery of the roll 28 intercepts the light beam of the detector 66 causing the detector to emit an output signal to controller 47 which thereupon stops the splicer head drive motors 62a. The distance actually moved by the splicer head 36 is detected by an encoder 68 coupled to one of the pinions 62 as shown in FIG. 4.

Splicer head 36 carries, in addition to rollers 58, means in the form of a brush bar 72 for pressing the running web W against the periphery of the ready roll 28 when the splicer head is in its advanced position shown in FIG. 2. The opposite ends of the brush bar 72 are swingably.supported to the splicer head side plates 36a by a pair of links 73. The brush bar is movable between a retracted position shown in FIGS. 1 and 2 and an advanced or paste position shown in FIG. 4. The brush bar is moved between its two positions by actuators 74 whose armatures are connected to links 73.

Head 36 also supports a knife 76 which can be moved by actuators 77 mounted to the head side plates 36a between a retracted position shown in FIGS. 1 to 3 and an advanced or cutting position shown in FIG. 4 for cutting the running web W. Actuators 77 are also controlled by signals from controller 47.

FIG. 5 shows the various signals to and control signals from controller 47. The controller also has various other inputs and outputs necessary for the proper operation of any turret splicer but which do not bear on this invention.

Referring to FIGS. 2, 4 and 5, when splicer 10 is operated to splice the leading edge of the web on ready roll 28 to running web W at line speed or higher, as soon as the running web roll 26 unwinds to a selected minimum diameter, a signal is applied to controller 47 indicating this fact. That signal may be generated by any means well known in the art. In response to that signal, the controller issues signals to accelerators 52 causing them to engage and rotate roll 28 which is now in the position shown in FIG. 2. The tape sensor 46 monitoring roll 28 is located at a fixed angle around roll 24 with respect to the splicing location P in FIG. 2. In the illustrated splicer, the relevant sensor 46 is located about 70° ahead of location P. Front panel control 47a on controller 47 allows the operator to select where the tape T will be, i.e. phase angle, when the running web W is first pressed against the ready web roll 28 during splicing. The tape should be positioned at least 40°, and more preferably 330° to 350° ahead of location P, so that the two webs will remain in contact for a relatively long time before the webs are actually pasted together. This helps to optimize the speed match as noted above.

Roll 28 is accelerated, in accordance with a selected acceleration ramp programmed into the controller, to a fixed speed. As noted above, this speed may be the nominal line speed of the web consuming machine or a speed somewhat greater than line speed. If the latter means that during the interval of speed match, the accumulator is being filled up with web rather than being emptied of web. During this acceleration time or beforehand, the controller also controls the splicer head drive motor 62a to move the splicer head toward the rotating ready roll 28 until the detector 66 on the splicer head senses the periphery of that roll. Since the roll is not an exact cylinder, its cylindrical surface may have high and low points. Therefore, the splicer head 36 is preferably advanced along rails 58 in small increments, e.g. 1/8 inch, with roll 28 executing a full revolution between increments so that the detector 66 will detect the high point on the roll. This assures that when the splicer head 36 is in its advanced position for any given roll 28 diameter, the web W will make its closest approach to the highest point on the roll. Obviously, if the splicer head were any closer, an unwanted paste could result.

Controller 47 subtracts from the fixed distance between the head home position and the roll 28 axis the distance moved by the splicer head 36 to its advanced position, which is reflected by the signal from the head encoder 68, to determine the diameter of roll 28. The controller also "knows" the angular velocity of roll 28 from the output of the tachometer 54. From these two parameters, the controller can determine the actual surface speed of roll 28 and adjust it through accelerators 52 so that it is exactly at the desired line speed. The controller also knows the exact speed of the running web from the output of tachometer 44 (FIG. 2) . Therefore, it can control the brake 32 associated with the running roll and drive roler 45 if splicing speed exceeds line speed to match the speed of the running web to that of the ready roll surface. As noted above, speed match by running web speed control can be achieved quite quickly and precisely due to the relatively low inertia of the running roll. When the signals from tachometer 44 and encoder 54 indicate a nominal speed match, i.e. same frequency, controller 47 issues a control signal to actuator 74 causing the brush bar 72 to press the running web W against the periphery of the ready roll. The brush on the bar allows some slippage between the two webs to minimize tension upset upon web contact.

As noted above, the two webs are preferably pressed together just after the splicing tape T has passed the splicing location P. Therefore, the two webs will remain in contact for almost a full revolution of the roll 28 thereby optimizing the web speed match and assuring that the webs will be pasted properly when the tape T next passes through the nip at splicing location P.

After a selected member of signals from encoder 54 following the paste, controller 47 issues a control signal to the knife actuators 77 causing the knife 76 to sever the running web W just behind the splice thereby separating that web from its depleted roll core. From this point on, the web consuming machine draws its web requirement from the ready roll 28. Controller 47 now returns the splicer head 36 to its retracted position shown in FIG. 1 and retracts and denergizes the accelerators 52. At some later time, the controller actuates the turret motor 18 to raise the roll 28 from the floor to the same position occupied by roll 26 in FIG. 1. The core of the expired roll 26 can now be removed from the lower set of chucks 24 and a new ready web roll prepared for the next splice cycle.

A suitable circuit for controlling the location of tape

T relative to the location P at the initiation of web contact and the firing of knife 76 is shown in FIG. 6. It should be understood, however, that there are other ways for accomplishing the same objectives that can be envisioned by those skilled in the art after reading this disclosure.

When the controller 47 starts the accelerators 52 at the beginning of the splice cycle, it also applies a signal to a flip flop 92. The resulting output signal from the flip flop is applied to a gate 94 which also receives a signal from the splicing tape sensor 46. When the detector senses the presence of tape T, gate 94 sets a flip flop 96. The resulting output of the flip flop is applied to a gate 98. The other input of that gate are signals from encoder 54 which are then gated to a counter 102. Counter 102 counts down from a number contained in register 104, which number can be set by a control on the controller front panel 47a. The signal from gate 94 loads the register number into the counter. When the count in counter 102 reaches zero that is detected by a zero detector 105 which thereupon sets a flip flop 106. The signal from that flip flop is applied to actuators 74 thereby moving the brush bar 72 to its advanced postition shown in FIG. 4. The signal from flip flop 106 also resets flip flops 92 and 96. However, the signal from the flip flop 106 is maintained until after the running web is severed as will be described presently. Thus by controlling the number in register 104 by means of the front panel control, the angular position or phase angle of the tape T at the time the two webs are first pressed together at location P may be adjusted. As noted above, most preferably, the two webs are brought together just after the tape passes through the nip at splicing location P. The signal from flip flop 106 also sets a flip flop 108.

The output of that flip flop log is applied to a gate 110 which also receives the detector 46 signal. Upon the occurence of that signal indicating that tape T has passed by detector 46 a second time, gate 110 sets a flip flop 112. The output of that flip flop enables a gate 114 which passes signals from encoder 54 to a counter 116. Counter 116 counts down from a number set into register 118 by a control on front panel 47a. That number is loaded into the counter 116 by a signal from gate 110. When counter 116 counts down to zero, that is detected by a zero detector 122 which thereupon issues a signal to the actuator 77 to fire knife 76 thereby severing the running web. The signal from detector is also applied to reset flip flops 106, 108 and 112. Thus, by adjusting the number set into register 118 using the front panel control, the length of the tail left behind tape T after splicing may be adjusted. As noted, it is usually made as short as possible.

Splicer 10 may be operated in more or less the same way to make a splice at a selected splicing speed less than line speed. For example, the line speed may be 3000 fpm with the splice being carried out at 1500 fpm. As before, the prepared ready roll 28, positioned as shown in FIG. 2, is accelerated up to the selected speed, e.g. 1500 fpm. In this case, controller 47 also applies control signals to the brake

32 associated with the running roll 26 to decelerate that roll according to a desired deceleration ramp so that the running web W reaches the selected splicing speed at more or less the same time as or later than the surface of the ready roll 28. As before, the speed of the running web W is matched to the ready roll surface speed rather than vice versa to achieve a precise speed match in a minimum length of time. While web W is drawn from roll 26 at the reduced speed, the web consuming machine draws its web requirements from the accumulator 42.

The splicer now functions in the same way described above to press the running web W against the ready roll just after the splicing tape T has passed through the splicing location P. As soon as contact has been made and before the actual paste, controller 74 de-actives the brake 32 retarding running roll 26 and controls drive roller 45 and accelerators 52 to accelerate both webs while they remain speed matched. When the splice tape T next passes through location P, the two webs will be pasted together, following which the running web W may be severed as described above.

Acceleration of the ready roll 28 continues until the web being drawn from that roll reaches line speed. Actually, as noted above, the web from roll 28 may be accelerated to a speed somewhat greater than line speed in order to replenish accumulator 42 with substantially the same amount of web that was drawn out during the aforesaid splice cycle. As noted above, this amount should be a minimum because speed match was achieved by adjusting to a predetermined speed of the ready roll rather than of the running web and because acceleration of the ready roll commenced at speed match prior to the actual pasting of the webs.

When splicer 10 is operated in the zero speed splice mode, the ready roll 28 is not accelerated to any great extent prior to the paste. Rather, upon operator command prior to the beginning of the splice cycle, controller 47 actuates the accelerators 52 to index roll 28 around until the relevant sensor 46 detects the splicing tape T. The controller then continues to index the roll according to the number set into counter 102 so that the splicing tape T is positioned at a selected angle relative to the splicing location P, e.g. just past it, and actuates the associated brake 32 to hold roll 28 at that position. Controller also controls the brake 32 operating on the running roll 26 to slow the running web W to a stop and moves the splicer head 36 to its advanced position. Following this, the controller causes the brush actuator 74 to move the brush to its advanced position thereby pressing web W against the ready roll. Again, as soon as a speed match was indicated, i.e. running web at zero speed, the controller 47 issued signals to accelerators 52 and the web drive roller 45 to accelerate both webs. As soon as the tape T next passes through the nip at splicing location P, the two webs are pasted together, following which the knife may be actuated to separate the running web from the depleted roll core 26. Some motion of the web W is desirable even in this zero speed mode of operation because a knife penetrating a moving web can produce complete cut of even a heavy web.

Acceleration of the web from roll 28 continues until that web reaches line speed or, for a short time, a speed greater or less than line speed in order to replenish or draw down web accumulator 42. Here again, the ability of splicer 10 to commence accelerating the running web W and the web on roll 28 even before those two webs are pasted together minimizes the time the running web remains at zero speed which is the time during which the web draw down in accumulator 42 is at a maximum. Resultantly, a smaller accumulator can be used with the splicer.

Preferably, the accumulator employs a fast response dancer incorporating carbon fiber rolls and a clutch instead of an air cylinder to move the dancer. This enables the system to respond quickly to compensate for any slight web speed mismatch when the two webs are pressed together.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in carrying out the above method and in the construction set forth without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Claims

1. A method of splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web wound upon a rotatably supported ready roll, said leading edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said method comprising the steps of: a. controlling the angular velocity of one of said rolls to obtain a speed match between the first web and the ready roll periphery; b. determining the instantaneous angular position of said leading edge margin; c. pressing the first web against the ready roll periphery to form a nip at a time when said leading edge margin is at a selected phase angle ahead of the nip; d. upon obtaining said speed match, angularly accelerating the ready roll to advance said leading edge margin through said nip thereby forming a splice between the two webs; e. severing the moving first web behind the splice; and f. continuing the acceleration of the ready roll until the second web now feeding into the accumulator reaches a selected speed.

2. The method defined in claim 1 wherein the speed match is obtained by maintaining the ready roll at a selected angular position and decelerating the first web to zero speed.

3. The method defined in claim 2 wherein said selected speed is said line speed. 4. The method defined in claim 2 wherein: a. said selected speed is made greater than line speed to increase the amount of web stored in the accumulator; and b. the speed of the second web is reduced to line speed when the amount of web in the accumulator reaches a selected amount.

5. The method defined in claim 2 wherein: a. the selected speed is made less than line speed to reduce the amount of web stored in the accumulator following the splice; and b. the speed of the second web is reduced to line speed when the amount of web in the accumulator reaches a selected amount.

6. The method defined in claim 1 wherein: a. the speed match is obtained by accelerating the ready roll until its peripheral surface speed equals a selected splicing speed; and b. adjusting the speed of the first web until it matches that of the ready roll periphery.

7. The method defined in claim 6 wherein the splicing speed is said line speed.

8. The method defined in claim 6 wherein: a. the splicing speed is less than said line speed; and b. the speed match is obtained by accelerating the ready roll until its peripheral surface speed equals said splicing speed and decelerating the first web by braking the ready roll until the first web speed matches that of the ready roll periphery. 9. The method defined in claim 6 wherein the splicing speed is greater than said line speed, and the speed match is obtained by accelerating the ready roll until its peripheral surface speed equals said splicing speed and accelerating said first web with an acceleration roll downstream from the nip until the first web speed matches that of the ready roll periphery. 10. The method defined in claim 1 wherein the speed match is obtained by: a. detecting the speed of the first web and producing web speed signals indicative thereof; b. detecting the phase and velocity of the ready roll and producing first signals indicative thereof; c. detecting the initial diameter of the ready roll and producing second signals indicative thereof; d. producing from said first and second signals a roll speed signal indicative of the ready roll peripheral surface speed; e. comparing said web speed and roll speed signals to derive an error signal; and f. controlling the speed of the first web according to said error signal.

11. The method defined in claim 10 wherein said time of pressing is determined by: a. sensing a mark on the periphery of the ready roll and producing a sensing signal in response thereto; b. counting said first signals following said sensing signal; and c. carrying out said pressing step when said count reaches a selected number. 12. The method defined in claim 11 wherein the severing step is carried out after said count has reached a chosen number higher than said selected number.

13. The method defined in claim 1 wherein said selected phase angle is 40° to 355°. 14. The method defined in claim 13 wherein said selected phase angle is 330° to 355°.

15. A method of splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge of a second web wound up on a rotatably supported ready roll, said edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said method comprising the steps of a. accelerating the ready roll until its periphery attains a selected splicing speed less than said line speed; b. decelerating the first web until its speed approaches the peripheral surface speed of the ready roll; c. pressing the first web against the periphery of the ready roll to form a nip at a time when said leading edge margin is absent from the nip; d. as soon as the first web is speed matched to the ready roll periphery and independently of the angular position of said leading edge margin, simultaneously accelerating the first web at a point downstream from the nip and angularly accelerating the ready roll to maintain the speed match so that a splice is made between the two webs the next time said leading edge margin passes through said nip; e. severing the moving first web behind the splice, and f. continuing the acceleration of the ready roll until the second web attains a selected speed at or near said line speed. 16. The method defined in claim 15 wherein said selected speed is greater than line speed so that the amount of web in the accumulator increases during speed matching. 17. The method defined in claim 15 wherein the selected speed is less than said line speed so that the amount of web in the accumulator continues to decrease following the splice.

18. The method defined in claim 15 wherein the pressing step is performed when the leading edge margin of the second web is at a small phase angle beyond said nip so that the two webs are pressed together for almost a full revolution of the ready roll prior to said splice thereby optimizing said speed match at the time of the splice.

19. Apparatus for splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web wound upon a rotatably supported ready roll, said leading edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said apparatus comprising a. means for controlling the angular velocity of one of said rolls to obtain a speed match between the first web and the ready roll periphery; b. means for determining the instantaneous angular position of said leading edge margin; c. means for pressing the first web against the ready roll periphery to form a nip at a time when said leading edge margin is at a selected phase angle ahead of the nip; d. means for angularly accelerating the ready roll upon obtaining said speed match to advance said leading edge margin through said nip thereby forming a splice between the two webs; e. means for severing the moving first web behind the splice; and f. means for continuing the acceleration of the ready roll until the second web now feeding into the accumulator reaches a selected speed. 20. The apparatus defined in claim 19 wherein the means for angularly accelerating upon obtaining speed match comprise a. means for accelerating the ready roll until its peripheral surface speed equals a selected splicing speed; and b. means for adjsting the speed of the first web until it matches that of the ready roll periphery.

21. The apparatus defined in claim 20 wherein the means for angularly accelerating upon obtaining speed match comprise: a. means for detecting the speed of the first web and producing web speed signals indicative thereof; b. means for detecting the phase and velocity of the ready roll and producing first signals indicative thereof; c. means for detecting the initial diameter of the ready roll and producing second signals indicative thereof; d. means for producing from said first and second signals a roll speed signal indicative of the ready roll peripheral surface speed; e. means for comparing said web speed and roll speed signals to derive an error signal; and f. means for controlling the speed of the first web according to said error signal. 22. The apparatus defined in claim 19 wherein said pressing means comprise: a. means for sensing a mark on the periphery of the ready roll and producing a sensing signal in response thereto; b. means for counting said first signals following said sensing signal, and c. means for controlling the pressing means to press said webs together when said count reaches a selected number. 23. Apparatus for splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge of a second web wound up on a rotatably supported ready roll, said edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said apparatus comprising: a. means for accelerating the ready roll until its periphery attains a selected splicing speed less than said line speed; b. means for decelerating the first web until its speed approaches the peripheral surface speed of the ready roll; c. means for pressing the first web against the periphery of the ready roll to form a nip at a time when said leading edge margin is absent from the nip; d. means for simultaneously accelerating the first web at a point downstream from the nip and angularly accelerating the ready roll as soon as the first web is speed matched to the ready roll periphery to maintain the speed match so that a splice is made between the two webs the next time said leading edge margin passes through said nip; e. means for severing the moving first web behind the splice, and f. means for maintaining the acceleration of the ready roll until the second web attains a selected speed at or near said line speed.

AMENDED CLAIMS

[received by the International Bureau on.11 January 1993 (11.01.93); original claims 1,2,5,8,10,15 and 19-23 amended; new claims 24-29 added; remaining claims unchanged (9 pages)]

1. A method of splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web wound upon a rotatably supported ready roll, said leading edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said method comprising the steps of: a. measuring the line speed of said running roll; b. measuring the angular velocity of said ready roll; c. measuring the diameter of the ready roll to determine the velocity of the ready roll periphery; d. controlling the angular velocity of one of said rolls to obtain a speed match between the first web and the ready roll periphery; e. determining the instantaneous angular position of said leading edge margin; f. pressing the first web against the ready roll periphery to form a nip at a time when said leading edge margin is at a selected phase angle ahead of the nip; g. upon obtaining said speed match, angularly accelerating the ready roll to advance said leading edge margin through said nip thereby forming a splice between the two webs; h. severing the moving first web behind the splice; and i. continuing the acceleration of the ready roll until the second web now feeding into the accumulator reaches a selected speed.

2. The method defined in claim 1 wherein the speed match is obtained at line speeds between zero and three thousand feet per minute. 3. The method defined in claim 2 wherein said diameter of said ready roll is measured by use of an optical sensor which measures the high spots of the roll.

4. The method defined in claim 2 wherein: a. said selected speed is made greater than line speed to increase the amount of web stored in the accumulator; and b. the speed of the second web is reduced to line speed when the amount of web in the accumulator reaches a selected amount.

5. The method defined in claim 2 wherein: a. the selected speed is made less than line speed to reduce the amount of web stored in the accumulator following the splice; and b. the speed of the second web is increased to line speed when the amount of web in the accumulator reaches a selected amount.

7. The method defined in claim 6 wherein the splicing speed is said line speed.

8. The method defined in claim 6 wherein: a. the splicing speed is less than said line speed but not zero; and b. the speed match is obtained by accelerating the ready roll until its peripheral surface speed equals said splicing speed and decelerating the first web by braking the ready roll until the first web speed matches that of the ready roll periphery.

9. The method defined in claim 6 wherein the splicing speed is greater than said line speed, and the speed match is obtained by accelerating the ready roll until it peripheral surface speed equals said splicing speed an accelerating said first web with an accelerating rol downstream from the nip until the first web speed matche that of the ready roll periphery.

10. The method defined in claim 1 wherein the spee match is obtained by: a. detecting the speed of the first web and producing web speed signals indicative thereof; b. detecting the phase angle and velocity of the ready roll and producing first signals indicative thereof; c. detecting the initial diameter of the ready roll and producing second signals indicative thereof; d. producing from said first and second signals a roll speed signal indicative of the ready roll peripheral surface speed; e. comparing said web speed and roll speed signals to derive an error signal; and f. controlling the speed of the first web according to said error signal.

11. The method defined in claim 10 wherein said time of pressing is determined by: a. sensing a mark on the periphery of the ready roll and producing a sensing signal in response thereto; b. counting said first signals following said sensing signal; and c. carrying out said pressing step when said count reaches a selected number.

12. The method defined in claim 11 wherein the severing step is carried out after said count has reached a chosen number higher than said selected number.

13. The method defined in claim 1 wherein said selected phase angle is 40° to 355°.

14. The method defined in claim 13 wherein said selected phase angle is 330° to 355°.

15. A method of splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web wound up on a rotatably supported ready roll, said edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said method comprising the steps of: a. accelerating the ready roll until its periphery attains a selected splicing speed less than said line speed; b. decelerating the first web until its speed approaches the peripheral surface speed of the ready roll, said peripheral surface speed determined by measuring the diameter of the ready roll and the angular velocity of the ready roll; c. pressing the first web against the periphery of the ready roll to form a nip at a time when said leading edge margin is absent from the nip; d. as soon as the first web is speed matches to the ready roll periphery and independently of the angular position of said leading edge margin, simultaneously accelerating the first web at a point downstream from the nip and angularly accelerating the ready roll to maintain the speed match so that a splice is made between the two webs the next time said leading edge margin passes through said nip; e. severing the moving first web behind the splice, and f. continuing the acceleration of the ready roll until the second web attains a selected speed at or near said line speed.

16. The method defined in claim 15 wherein said selected speed is greater than line speed so that the amount of web in the accumulator increases during speed-matching.

17. The method defined in claim 15 wherein the selected speed is less than said line speed so that the amount of web in the accumulator continues to decrease following the splice.

19. Apparatus for splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web wound upon a rotatably supported ready roll, said leading edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said apparatus comprising: a. means for controlling the angular velocity of one of said rolls to obtain a speed match between the first web and the ready roll periphery; b. means for determining the instantaneous angular position of said leading edge margin. c. means for pressing the first web against the ready roll periphery to form a nip at a time when said leading edge margin is at a selected phase angle ahead of the nip; d. means for angularly accelerating the ready roll upon obtaining said speed match to advance said leading edge margin through said nip thereby forming a splice between the two webs; e. means for severing the moving first web behind the splice; f. means for continuing the acceleration of the ready roll until the second web now feeding into the accumulator reaches a selected speed; g. means for determining the diameter of said ready roll; h. means for determining the angular velocity of the ready roll; and i. means for determining the line speed of said first web.

20. The apparatus defined in claim 19 wherein the means for angularly accelerating upon obtaining speed match comprise: a. means for accelerating the ready roll until its peripheral surface speed equals a selected splicing speed; and b. means for adjusting the speed of the first web until it matches that of the ready roll periphery.

21. The apparatus defined in claim 20 wherein the means for angularly accelerating upon obtaining speed match comprise: a. means for detecting the speed of the first web and producing web speed signals indicative thereof; b. means for detecting the phase angle and velocity of the ready roll and producing first signals indicative thereof; c. means for detecting the initial diameter of the ready roll and producing second signals indicative thereof; d. means for producing from said first and second signals a roll speed signal indicative of the ready roll peripheral surface speed; e. means for comparing said web speed and roll speed signals to derive an error signal; and f. means for controlling the speed of the first web according to said error signal.

22. The apparatus defined in claim 19 further comprising: a. means for sensing a mark on the periphery of the ready roll and producing web speed signals indicative thereof; b. means for counting plural first signals following said sensing signal, and c. means for controlling the pressing means to press said webs together when said count reaches a selected number.

23. Apparatus for splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web would up on a rotatably supported ready roll, said edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said apparatus comprising: a. means for accelerating the ready roll until its periphery attains a selected splicing speed less than said line speed but greater than zero; b. means for decelerating the first web until it speed approaches the peripheral surface speed of the ready roll; c. means for pressing the first web against the periphery of the ready roll to form a nip at a time when said leading edge margin is absent from the nip; d. means for simultaneously accelerating the first web at a point downstream from the nip and angularly accelerating the ready roll as soon as the first web is speed matched to the ready roll periphery to maintain the speed match so that a splice is made between the two webs that next time said leading edge margin passes trough said nip; e. means for severing the moving first web behind the splice; f. means for maintaining the acceleration of the ready roll until the second web attains a selected speed at or near said line speed; g. means for determining the diameter of said ready roll; h. means for determining the angular velocity of the ready roll; and i. means for determining the line speed of said first web.

24. A method of splicing a first web, drawn from a rotatably supported running roll and feeding into a web accumulator serving web to a web consuming machine running at a substantially constant line speed, to the leading edge margin of a second web wound upon a rotatably supported ready roll, said leading edge margin being releasably attached to the periphery of the ready roll and carrying an adhesive on the outer surface thereof, said method comprising the steps of: a. determining the angular velocity of said ready roll; b. determining the line speed of said running roll; c. determining the diameter of the ready roll; d. matching the speed of said ready roll and the speed of said prior to splicing; e. splicing said web of said ready roll to said running roll; and f. severing the moving first web behind the splice.

25. The method of Claim 24 wherein said angular velocity of said ready roll is determined through use of a shaft encoder on a ready roll accelerator driver.

26. The method of Claim 24 wherein said angular velocity of said ready roll is determined through use of a shaft encoder on a ready roll chuck.

27. The method of Claim 24 wherein said angular velocity of said ready roll is determined through use of a tachometer on a ready roll chuck.

28. The method of Claim 24 wherein said line speed of said running roll is determined through use of an idler roller having a means for measuring the angular velocity of said idler roller.

29. The method of Claim 24 wherein said diameter of said ready roll is determined through use of an optical sensor.