US3150574A

US3150574A - Method and apparatus for cutting spirally wound tubes in accurate register

Info

Publication number: US3150574A
Application number: US128565A
Authority: US
Inventors: Francis G Glasby
Original assignee: Robinson and Sons Ltd
Current assignee: Robinson and Sons Ltd
Priority date: 1961-08-01
Filing date: 1961-08-01
Publication date: 1964-09-29
Anticipated expiration: 1981-09-29
Also published as: GB985793A

Description

Sept. 29, 1964 F. G. GLASBY METHOD AND APPARATUS FOR CUTTING SPIRALLY WOUND TUBES IN ACCURATE REGISTER 3 Sheets-Sheet 1 Filed Aug. 1, 1961 NFQQ m/QR

Sept. 29, 1964 F. G. GLASBY 3,150,574

METHOD AND APPARATUS FOR CUTTING SPIRALLY WOUND TUBES IN ACCURATE REGISTER Filed Aug. 1, 1961 3 Sheets-Sheet 2 VELOGITYV+E I, I

I P 9 X I r '%45'/ I40 I I mourn! v l3 6 l5 RELATIVE SPEED APPARATUS -ABSOLUTE CUTTER SPEED YABQOLU CUQER SPEED -GUTTING OPERATION REGISTERING OPERATION INVENTOR.

, Franc/'5 G. G/asoy BY MS attorneys P 29, 1964 F. G. GLASBY 3, 50,

METHOD AND APPARATUS FOR CUTTING SPIRALLY WOUND TUBES IN ACCURATE REGISTER Flled Aug. 1, 1961 3 Sheets-Sheet 3 United States Patent O METHUTB AND AFPARATUS FOR CUTTENG SPHRALLY WOUND TUBES lN ACUURATE REGHSTER Francis G. Glasby, Chesterfield, England, assignor to Robinson 8.: Sons Ltd, Chesterfield, England, a British company Filed Aug. 1, 1961, er. No. 128,565 19 Claims. (Cl. 93-fitl) This invention relates to a method and apparatus for producing spirally wound cylindrical tubes, useful, for example, in making containers, said tubes having a spirally wound pattern strip thereon, and more particularly to cutting tubes in accurate register with the patterns on the strip. The invention is most useful with a unitary pattern strip, as distinguished from a barbers pole pattern.

By way of background it may be explained that cylindrical containers can be made by winding strip material on a mandrel to form a tube and then cutting the tube to the desired length. Sometimes the tube is cut as it is formed by a single cutter into the length desired for one container. Again a length suitable for several containers may be cut oil the tube as it is formed and later cut up into container lengths; or in a third approach a number of container lengths may be cut oil by a so-called gang cutter simultaneously.

T he tube as it is made often contains so-called unitary patterns along its length. Unitary patterns are significant groupings of lines, letters or symbols such as might be used to decorate a container to which can be assigned a beginning and an end as contrasted with a barbers pole pattern having no identifiable beginning or end.

in the case of unitary patterns it is, of course, desirable that when a tube section is cut off, the out be coordinated with the pattern so that it will not mar the pattern. Hitherto it has been difiicult to achieve satisfactory coordination and it has been necessary to provide for trim space in the pattern strip, so that if the cut is not made in exact coordination with the pattern, the pattern itself will not be spoiled.

One object of the invention is to provide for a more accurate coordination between the pattern and the end of a container or tube than has hitherto been possible.

Another object of the invention is to eliminate the necessity for trim in the pattern strip and yet to obtain containers which are in accurate register with the pattern strip.

In accordance with the invention these and other objects are achieved by a method which comprises spirally winding a tube having a pattern at a predetermined axial speed, moving cutting means axially of the tube from a position remote, in an axial direction, from the position where it is desired to cut the tube, at a speed relative to the tube such that said cutting means approach a position where it is desired to cut the tube and then substantially eliminating relative movement between the cutting means and the tube when observation shows the pattern is in register with the cutting means and cutting oil a tube.

In the drawings FIGURE 1 is a plan view of a single saw cutoir winding machine embodying the present invention, showing the machine at the moment when the pattern has just been observed and the cutting cycle is about to commence.

FIGURE 2 is a detailed view in elevation of the saw and associated parts at the same moment.

FIGURE 3 is a diagrammatic view of the hydraulic circuitry controlling the movements of the cutter carriage both when moving at a difierent speed from that of the 3,l5b,574 Fasten-ted? Sept. 29, 1964 beingwound tube and when moving at thesame axial speed after a registering operation has been carried out.

FIGURE 4 is a diagram of a self-holding circuit associated with the movement of the cutter carriage.

FIGURE 5 is a view on an enlarged scale suggesting the difference in absolute and relative speed of the cutter carriage and the tube.

FIGURE 6 is a diagram showing the absolute and relative speeds of the tube and the cutter and their relation to the electric eye during both the cutting and registering operations.

FIGURE 7 is a schematic plan view of a winding machine showing one way in which tubing may be formed on a mandrel.

FIGURE 8 is a partial view of a winding machine showing an alternate way in which relative movement between tube and cutting means can be obtained.

FIGURE 9 is a view in vertical section of a diiferential for use in the embodinent of FIGURE 8.

Referring to FIGURES 1 and 7, a tube is wound on a mandrel 9a. The tube may comprise one or more base layers 95 which may be found on the mandrel by conventional means. Thus, as shown in FIGURE 7, the strips 911 are unwound from supply sources (not shown), wrapped on the mandrel and the tube thus formed advanced on the mandrel by means of a belt which may in turn be driven by any convenient means, for example, by shaft ltll and the apparatus shown in FIGURE 8 (see also Robinson Patent 2,699,099).

Gn top of the base layers 9b is wound a pattern bearing outer strip 18. This will preferably contain a unitary pattern and at regular intervals a control mark 17. This mark, when wound on to the tube will preferably though not necessarily form a complete circle around the periphery of the tube as at Ma and 14!) (see FIGS. 1 and 5). It may be oi any suitable nature, Le. a special ink, a fluorescent patch, a magnetic marking or even a physical irregularity such as a hole or slight bump, depending on the observing means it is desired to employ. Preferably, however, the mark is such that it can be distinguished from other areas of the strip by a photoelectric cell.

As shown in FIGURE 1, the strip 18 hearing the mark 17 is fed toward the tube 9. A photoelectric cell 19 and an associated light source 243 are located adjacent the tube and when the mark 17 passes near them a signal is sent from cell 19 to an amplifier 21 causing normally

open switches

22 and 23 to close. The purpose of these switches is described below.

Located adjacent the mandrel 9a and the tube being formed thereon is a rotary saw 1. This saw is driven by a motor 2. (The electrical connections for the motor are not shown for the purposes of simplicity.) The motor 2 is attached to a bracket 3 which is slid along a keyed shaft 4 under the influence of an hydraulic cylinder 5 containing a piston (not shown) having a rod 7. The hydraulic cylinder 5 is mounted on the bed plate 6 of the machine. The rod '7 of the piston is attached to the motor bracket 3 by means of an intermediate puslur frame 3 in such a manner that any extension of the plunger of the hydraulic cylinder 5 will cause movement of the cutting saw 1 in a direction axial of the mandrel To cut tube 9 it is necessary for the cutting saw 1 to move transversely from the position shown in FI URES l and 2 into engagement with the tube 9. For this purpose a lever 10 is attached to the keyed shaft 4 so that operation of a solenoid ill in the direction of the arrow 12 in FIGURE 2 will cause rotation of the keyed shaft 4 in such a manner as to rock motor bracket 3 bringing the saw thereon into engagement with the tube 9.

It has been noted that axial movement of the saw Q in assembly is achieved by means of cylinder 5. Details of a preferred system are shown in FIGURE 3. As shown in that figure, the hydraulic cylinder is provided with ports 34 and 39. These ports are connected via tubes 34a and 39a to an hydraulic valve 26. The valve 26 has an inlet port 29 which is connected to an hydraulic pump 27 via a line 27a and to another hydraulic pump 28 via a line 28a and a second valve 37. Exhaust ports 35 connect the valve 26 to a reservoir 192. via a line 1%. Motors 27b and 28b drive pumps 27 and 23, respectively.

The valve 26 is operated by a solenoid 24 which in turn is energized by the closing of switch The operation of valve 37 is effected by a solenoid 31 which is energized by closing of a switch 33. The latter, normally open, is closed upon a signal being received by photoelectric cell 15.

The operation of the system just described will now be explained.

FIGURES 1-3 show the system at a moment when the cutting cycle is about to begin. Assume that the spirally wound tube 9 must be cut exactly at the locations 140 and 14b. As noted above, these positions are marked by some distinguishing feature such as that shown as 17 on the strip, capable of energizing the photoelectric cell when illuminated by a light beam from source 16.

When the control feature 1'7 on strip 18 activates cell 19, it closes switches and 23 as described above. Closing of switch 22 activates solenoid 2.4, axially displacing the spool 25' of valve 2 to allow fluid supplied by pumps 27 and 23 to pass from inlet port 29 to port 30 and thence to port 34- of hydraulic cylinder S. Thus the piston in cylinder 5 is displaced moving rod '7 and saw 1 axially of the tube.

As will appear from FIGURE 3, the supply of hydraulic fiuid consists of a main component, that from pump 27 and an auxiliary component from pump Pump 27 is adjusted so that its delivery is such as to move the rod 7 and saw 1 at the same axial speed as tube 9. The delivery of pump 28 on the other hand, is conveniently much less, say on the order of about 10% of that delivered by pump 27 so that during this phase with the additional fluid the saw moves faster than tube 9 by about this same proportion.

Now the photocell 19 is positioned with respect to tube 9 in such a way that axial movement of saw 1 does not occur until the marl; llda, where it is desired to cut, has already passed the saw 1. On the other hand, since the axial speed of the saw is slightly greater than the speed of the tube, the saw gains on the mark 14a.

It will be observed that the photocell 15 with its light source 16 and amplifier 32 are fixed to the frame 8 and hence move with the saw. It will further be recalled that the cell 15 was only sensitized with the closing of switch 23, is. after mark 14a had passed it. Now when the saw approaches mark Ma, a signal is given from cell 15 to amplifier 32, causing switch 33 to close. This in turn activates solenoid 3-1 which closes valve 3'7 cutting off the auxiliary fluid to cylinder 5. Thus the speed of the saw is reduced to that of the tube and relative motion ceases.

As the saw 1 moves along with the tube 9, a spring loaded trip lever 41, attached to frame 3, engages a roller 42 associated with a hinged lever 4-3 to raise a sliding rod 44 and contact bar attached thereto to bridge contacts A which form a part of a self-holding circuit shown in FIGURE 4. As will be evident from FIGURE 4, closing of contacts A energizes a solenoid B which in turn energizes solenoid ill and establishes a holding circuit for that coil. Solenoid 3.1, as noted above, swings lever 10, rocking saw 1 into cutting engagement with the tube.

After the tube has been severed, trip lever 41 engages a roller 46 associated with a hinged lever to raise sliding rod 43 and a contact her When bar 4-9 is raised it open normally closed contacts C, breaking the 4 holding circuit for solenoid 11. Spring 51 then causes the saw 1 to be returned to the position shown in FIG- URE 2.

Finally, in the last phase of the saw movement a member 52 attached to frame 8 engages a double switch 53 which resets contacts Z2, Z3 and etails of the resetting mechanism are not shown and are entirely conventional.

Resetting of switch 22 to open position deenergizcs solenoid 2d and resetting switch 33 decnergizes solenoid 31.

eenergization of

solenoids

24 and 31 allows the spools of

valves

26 and 37 to return to the position shown in FIGURE 3 and directs fluid into the port 39 of cylinder 5, moving the saw 1 back to its starting position.

Opening of switch 23 renders photocell 15 insensitive to further impulses.

To give an indication of the relative magnitude of the various distances involved in the above operation, assume the tube velocity is V and that when the saw begins to move the desired cutting position is a distance Y ahead of the saw. This is illustrated graphically in FIGURES 5 and 6. Assume further that the saw initially moves with a velocity V+E; then the saw will become level with the cutting point at some point P a distance Z ahead of the For a typical example where E is 10% of V and Y is /2", the calculated value of Z will be 5 /2". Conveniently, the relative velocities of the operative components may be represented in block form as in FIGURE 6, where the tube and cutter travel from right to left.

As will be seen from FIGURE 6, the absolute speed of the cutter is initially greater than the absolute speed of the tube so that the cutter will gain on the tube until the registering apparatus determines that such gain should cease by reason of a suitable positional relationship, represented as A in FIGURE 6, between the cutting means and the desired cutting position having been established. From this moment in time, a cutting operation is performed with the cutter and tube traveling at the same speed.

Some time lag may be involved in the circuitry and therefore provision is preferably made for the photocell 15 and source 16 to be adjustable from their nominal position relative to saw 1. Similarly, should it be desired to use a control mark which does not correspond exactly with the desired position of the cut, the photocell 15 can be adjusted to compensate for this.

The advantage of aligning the cutter with the reference point on the tube will readily be appreciated.

It is well known that errors of repetitive performance in combined circuitry such as is employed in this instance for initiating movement of the cutting means, where electrical relays, solenoid operated hydraulic valves and the like are employed, may be regarded as time errors, and the resulting space error, when applying such circuitry in determining the position of a moving element relative to a reference point, will be proportional to the time error and to the speed of the moving element. Obviously, if the reference point from which such determination of position is made, moves at a speed slightly greater or slightly less than the moving element, whereby the relative speed of the reference point and the moving element is small, the space error in determining the position of the moving element will be small. This advantage is a gain over a situation where the reference point is fixed. Obviously this method can be used where it is desired to coordinate two independently operating elements having no physical connection.

The invention has so far been described with reference to a system in which movement of the cutting device is commenced after the desired cutting point has moved past the cutting device and therefore in which the absolute speed of the cutting device is increased over the absolute speed of the tube to overtake the tube. It will be obvious to those skilled in the art that the movement of the cutting device can be commenced before the position of cut reaches the cutter with the cutter moving at a slower speed initially than the tube. Similarly, instead of increasing or decreasing the absolute speed of the cutter, the absolute speed of the tube may be varied to achieve the same effect. A suitable device for this purpose is shown in FKGURES 8 and 9.

For the construction now to be described it is proposed to achieve relative movement between the cutter and the tube by changing the speed of the tube during the registering operation which precedes the cutting operation. it is possible for this relative movement to be applied in two ways, either by placing the cutter behind the desired cutting location at the beginning of the registering operation and reducingthe speed of the tube during this registering period, or by placing the outer ahead of the desired cutting location at the beginning of the registering operation and increasing the speed of the tube during this registering period.

For the present embodiment it is proposed to describe the latter construction and reference should be made to FIGURES 7, 8 and 9.

In FIGURE 8 we show a cross-section of a conventional spiral tube winding head modified according to this embodiment wherein rotation from a main driving motor 142 is transmitted by shaft 143 to a pair of bevel gears 1G4 and 1435, and thence by shaft 199 to a differential gear assembly 107. This differential gear assembly 1167 consists of a casing 1% with support bearings for three shafts 169, 13th and H1, and the internal arrangement of this differential gear assembly is of well known principle in which rotation of main input shaft 109 can be transmitted through

bevel gears

112, 113, 114 and 115 to output shaft 110. Bevel gears 113 and 114 are mounted rotatably in a spider 116, said spider being rotatable about and independently of shaft 169 by engagement of worm Wheel 1117 with a Worm 11S mounted on shaft 111. Rotation can be imparted to the spider 1116 and its associated

bevels

113 and 114 by means of a motor 119 coupled to shaft 111 so that a component of rotation, additional to that provided by shaft 1%? can be imparted to bevel gear H5 and associated output shaft 119 when aforesaid motor 119 is rotated.

Output shaft 119 transmits rotary motion to winding belt pulleys 1%1 and 161a through the

intermediate bevel gears

122 and 123, shaft 124,

bevel gear pair

125 and 126,

bevel gear pair

127 and 128, and belt

pulley shafts

129 and 133. It will be obvious that if the spiral tube is being wound by belt Iltltl through rotation of winding belt pulleys 1'91 and Mia by reason of rotation of main driving motor 14-2 and the intermediate shafts and gearing already described, then the speed of winding the tube will be increased at required times by application of rotation of motor 119 in an appropriate directional sense. Thus we have a means for providing relative movement between the cutting means and the tube during the regisering period.

it is believed that the functioning of the system shown in FIGURES 8 and 9 will be obvious. Normally, before a cutting sequence starts the tube 9 is driven by power furnished by the motor 142 alone. As the tube advances along the mandrel and an additional length of pattern strip 153 is drawn to the tube, the control mark 17 triggers cell 19, closing switch 23 (see FIG. 1). This in turn energizes differential motor 11% which feeds a speed increment through the diiferential (FIGURE 9) to the output shaft iii? and thence to pulleys ltll, 161a and belt 109. Hence the tube moves at an increased rate.

Contacts 23, when closed, also energize solenoid 24 in the manner described above. However, in this embodiment the auxiliary hydraulic system comprising pump 2%. its associated motor, solenoid 31 and valve 3% and related tubing are omitted so that the saw 1 and its assembly are moved only by pump 27. The position of photocell 19 is arranged so that the saw 1 will begin its movement while it is ahead (Le. to the right in FIGURE 1) of the point where it is desired to cut. The delivery of pump 27 is such that the rate of movement of saw 1 is substantially equal to the rate of movement of the tube 9 before the speed component of the differential motor 119 is ap plied. When the speed increment from motor 119 is introduced, the tube thus catches up at a relatively slow rate with the cutter.

When the point at which it is desired to cut the tube reaches the photocell 15, switch 33 is closed, energizing solenoid 132 and thus opening contacts 133 in the circuit for differential motor 119. The speed of the tube is thus decreased to that of the saw and cutting can be commenced.

Resetting of contacts 22, 21% and 33 is carried out as described above.

Although the systems described both involve hydraulic drives for the cutting device and mechanical drives for the tube, it is obvious that mechanically driven cutters can he used with a mechanically driven tube or with an bydraulically driven tube. Similarly, an hydraulically driven tube can be used with hydraulically or mechanically driven cutters. Various other combinations of conventional drives will readily occur to those skilled in the art.

Although the embodiments so far described have used only one cutting saw, it is obvious that a gang of saws may be employed. Where a single saw is used, it may cut off a length of tube suitable for a single container at each cut, or a length of tube from which several containers can be made.

What is claimed is:

l. A method of producing cylindrical containers and the like bearing unitary patterns in close registry with the cut ends from continuously formed tube stock hearing unitary patterns on a surface in which there are the steps of spirally winding the tube stock at a substantially constant rate and simultaneously applying a web bearing unitary patterns and control features, said control features bearing constant positional relationship to cutting locations between patterns or groups of patterns, said patterns and control features appearing on the surface of the continuously moving tube so produced, then whilst Winding continues moving detector means at a speed different from that of the tube from a position remote from one of said control features in the same direction as the movement of the tube so that the speed of the detector means relative to the tube is less than the absolute speed of the tube wherein the detector means approaches the control feature followed by the steps of observing the control feature, said observing step automatically initiating cutting of the tube to sever it into lengths at said aforesaid cutting locations, whereby said lengths have patterns disposed in correct axial relationship with the cut ends.

2. A method of cutting precise lengths from continuously forming spirally wound tube bearing unitary patterns on its exterior, comprising the steps of winding the tube, spirally winding unitary pattern strips thereon, simultaneously moving the tube axially at a substantially constant speed, moving cutter means from a position remote from the cutting position at a substantially constant speed different from that of the tube so that the cutter approaches the desired cutting position at a speed relative to the tube speed which is less than the axial speed thereof, observing a cutting position bearing a fixed relation to the pattern on the axially moving tube, imparting to the cutter that speed which matches the speed of the tube when the cutter reaches the desired distance from the end of the pattern on the tube, and thereafter cutting the pattern and tube while maintaining the matching speed of cutter and tube. a

3. The methodof claim 2 havin thesteps of locating the observing means ahead of the cutter and moving the observing means in fixed relation to the cutter so that the two elements traverse together at the same speed as the tube during the cutting operation.

4. A method of producing cylindrical containers and the like bearing unitary patterns in close registry with the cut ends from continuously formed tube stock bearing unitary patterns on a surface in which there are the steps of spirally winding the tube stock at a substantially constant rate and simultaneously applying a web bearing unitary patterns and control features said control features bearing constant positional relationship to patterns or groups of patterns said patterns and control features appearing on the surface of the continuously moving tube so produced, then whilst winding continues moving detector means having cutting means attached thereto at a speed different from that or" the tube, from a position remote from the desired cutting position in the same direction as the movement of the tube so that the speed of the detector means relative to the tube is less than the absolute speed of the tube, said relative movement of the detector means causing said detector means to approach a control feature on the moving tube, followed by the steps of eliminating relative motion between the detector means and the tube when said control feature is detected by said detector means thereafter while said cutting means and tube are moving with the same speed and direction automatically severing the tube into lengths whereby said lengths have patterns disposed in correct axial relationship with the cut ends.

5. A method of producing cylindrical containers and the like bearing unitary patterns in close registry with the ends of the containers from tube stock being continuously formed bearing unitary patterns on a surface, wherein two detector means are used to achieve cutting register, comprising spirally winding the tube stock at a substantially constant rate and simultaneously applying a web bearing unitary patterns and control features, said control features bearing constant positional relationshi) to the patterns or groups of patterns, said patterns and control features appearing on the surface of the continuously moving tube so produced, having said first detector means cooperate for each cutting cycle with a control feature to initiate the movement of cutting means having a second detector means attached thereto, said cutting means being moved at a speed different from that of the tube, from a position remote from the desired cutting position, in the same direction as the movement of the tube, at which time the relative speed of the cutting means to the tube is less than the absolute speed of the tube and the second detector means attached to the cutting means approaches a control feature on the moving tube at a relative speed less than the absolute speed of the tube, followed by the steps of eliminating relative motion of the cutting means and the tube when the second detector means and control features achieve axial positional coincidence, said elimination of relative motion being automatically initiated by cooperation of the second detector means with said control feature, at which time the cutting means and the tube are moving with the same speed and direction axially as the cutting means in desired axial relationship with the patterns on the tube, and thereafter automatically applying the cutting means to the tube to sever into lengths;

wh reby said lengths have patterns disposed in correct axial relationship with the cut ends.

6. A method of producing cylindrical containers and the like comprising spirally winding a tube with a pattern strip, moving said tube at a predetermined absolute axial speed, moving cutting means with observation means attached thereto at a speed different from that of the tube from a point remote from the position on the tube where it is desired to cut the tube in the same direction as the movement of the tube so that the speed of the cutting means relative to the tube is less ban the absolute speed of the tube such that the cutting means approach the position where it is desired to cut the tube and then substantially eliminating relative movement between the cut ting means with its attached observation means and the tube when observation shows the pattern is in register with the cutting means, and cutting off the tube.

7. The method claimed in claim 6 wherein the relative movement between the cutting means and the tube is substantially eliminated by adjusting the speed of the tube.

8. The method claimed in claim 6, wherein said cutting means and its attached observation means are moved at an absolute speed which initially is greater than the absolute speed of the tube, and the relative movement between the cutting means and the tube is substantially eliminated by adjusting the speed of the cutting means according to observation of the pattern in register with the cutting means.

9. The method claimed in claim 6, wherein the tube is moved at an absolute speed which is initially greater than the absolute speed of the cutting means and its attached observing means thereby moving the position on the tube at which it is desired to make the cut towards the cutting means.

10. The method claimed in claim 9 wherein relative movement between the cutting means with its attached observation means and tube is eliminated by reducing the speed of the tube.

11. The method claimed in claim 6 wherein a single length of tube is cut off.

12. The method claimed in claim 6 wherein a plurality of tube sections are cut simultaneously.

13. A method of producing a cylindrical tube which comprises helically winding a pattern strip on a mandrel, moving the tube formed with the pattern strip axially of the mandrel at a predetermined absolute speed, moving a cutter with observation means attached thereto axially of the mandrel at an absolute speed which is different from the absolute speed of the tube, which results in the cutter approaching a point on the tube at which it is desired to cut the tube at a relative speed which is less than the absolute speed of the tube, observing a mark on said tube and when said mark has reached a point indicative of a proper cutting relation between said cutter and said tube, adjusting the absolute speed of the cutter and its attached observation means to conform to that of the tube and then cutting a section off said tube.

14. A method of producing a cylindrical tube which comprises helically winding a pattern strip on a mandrel, moving the tube formed with the pattern strip axially of the mandrel at an absolute speed which is different from the absolute speed of a cutting means with attached observation means, and which results in the cutter approaching a point on the tube at which it is desired to cut the tube at a relative speed which is less than the absolute speed of the tube, observing a mark on said tube and when said mark has reached a point indicative of a proper cutting relation between said cutting means with its attached observation means and said tube, adjusting the absolute speed of the tube to conform to that of the cutting means, and its attached observation means and then cutting a section of said tube.

15. A method of producing spirally wound cylindrical containers having a unitary pattern strip wound spirally thereon in which compensation for winding variables is obtained without the use of surplus strip material in the pattern strip, comprising the steps of spirally winding a tube with pattern strip, moving the tube axially at one axial speed, moving cutting means with attached observation means from a position of non-alignment with the point on the tube where it is desired to cut, axially at another speed which results in the cutter approaching a point on the tube where it is desired to cut the tube at a relative speed which is less than the absolute speed of the tube, observing the pattern strip until the cutting means and its attached observation means are in alignment with the desired cutting point on the tube, then reducing the relative axial speed of the tube and cutting means with its attached observation means to substantially zero and cutting off a length of tube containing material for one or more containers.

16. Apparatus for producing cylindrical containers and the like comprising; means for continuously spirally forming a tube with a pattern strip helically wound on its outer surface, means mounted thereon for moving the tube axially as it is formed, means for cutting the tube, means operatively connected to the tube forming means for moving the cutting means lengthwise of the tube in the same direction as the tube but at a diiferent initial speed from that of the tube so as to cause registry between the cutting means and the pattern, means carried on the cutting means for observing when pattern to cutting means registry occurs, and means responsive to an observation of such registry for thereafter maintaining said registry, said means for moving the cutting means comprising a hydraulic cylinder connected to the cutting means, a main pump and an auxiliary pump both operatively connected to said cylinder for delivering supplies of pressurized fluid to it at the same time, said main pump delivering fluid which causes the cutting means to move at the same speed and in the same direction as the tube, said auxiliary pump delivering fluid which causes the cutting means to move at a speed diiferent from that of the tube, said means for maintaining said registry comprising means for disconnecting said auxiliary pump from said cylinder accord ing to the observation of patterns to cutting means registry, whereby the tube and the cutting means move axially at the same speed during cutting.

17. The apparatus claimed in claim 16 wherein the observing means comprises a photoelectric cell.

18. The apparatus claimed in claim 16 and comprising second observing means located adjacent the pattern strip being wound on the mandrel and energizable by a control mark on said strip, the means for axially moving the cutting means being responsive to a signal from said second observing means.

19. Apparatus for producing cylindrical containers and the like comprising: means for continuously spirally forming a tube with a pattern strip helically wound on its outer surface, means mounted thereon for moving the tube axially as it is formed, means for cutting the tube, means operatively connected to the tube-forming means for moving the cutting means lengthwise of the tube in the same direction as the tube at a fixed speed, said means for moving the tube comprising main drive means for moving the tube at the same speed as the cutting means, and auxiliary drive means for providing additional movement to the tube so that its total speed is different from the Speed of the cutting means and so as to cause cutting registry between the patterns on the tube and the cutting means, means carried on the cutting means for observing when cutting registry occurs, and means responsive to said observing means for substantially eliminating relative movement between the cutting means and the tube according to an observation of cutting registry, said responsive means comprising means for disconnecting said auxiliary drive means from said tube when cutting registry is observed, whereby all axial speed dififerential between the tube and the cutting means is eliminated during the ciitting cycle.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

1. A METHOD OF PRODUCING CYLINDRICAL CONTAINERS AND THE LIKE BEARING UNITARY PATTERNS IN CLOSE REGISTRY WITH THE CUT ENDS FROM CONTINUOUSLY FORMED TUBE STOCK BEARING UNITARY PATTERNS ON A SURFACE IN WHICH THERE ARE THE STEPS OF SPIRALLY WINDING THE TUBE STOCK AT A SUBSTANTIALLY CONSTANT RATE AND SIMULTANEOUSLY APPLYING A WEB BEARING UNITARY PATTERNS AND CONTROL FEATURES, SAID CONTROL FEATURES BEARING CONSTANT POSITIONAL RELATIONSHIP TO CUTTING LOCATIONS BETWEEN PATTERNS OR GROUPS OF PATTERNS, SAID PATTERNS AND CONTROL FEATURES APPEARING ON THE SURFACE OF THE CONTINUOUSLY MOVING TUBE SO PRODUCED, THEN WHILST WINDING CONTINUES MOVING DETECTOR MEANS AT A SPEED DIFFERENT FROM THAT OF THE TUBE FROM A POSITION REMOTE FROM ONE OF SAID CONTROL FEATURES IN THE SAME DIRECTION AS THE MOVEMENT OF THE TUBE SO THAT THE SPEED OF THE DETECTOR