US3460445A

US3460445A - Tubemaking apparatus

Info

Publication number: US3460445A
Application number: US525156A
Authority: US
Inventors: Karl Ried
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-02-04
Filing date: 1966-02-04
Publication date: 1969-08-12
Anticipated expiration: 1986-08-12
Also published as: DE1249664B; CH455478A; GB1114144A

Description

5 Sheets-Sheet l Filed Feb. 4, 1966 r l j E m? INVENTOR.

Mar @feat Aug. l2, 1969 K. Rlr-:D 3,460,445

TUBEMAK ING APPARATUS INVENTOR. 14a, d ,@/u

Aug. l2, 1969 K. RIED l 3,460,445

TUBEMAKING APPARATUS Filed Feb. 4, 1966 5 Sheets-Sheet 3 INVENTOR um, @leg 'SY/wwf. MW

ATTORNEY nited 3,460,445 TUBEMAKING APPARATUS Karl Ried, Sanatorumstrasse, Unterageri, Switzerland Filed Feb. 4, 1966, Ser. No. 525,156 Claims priority, application Switzerland, Feb. 4, 1965, 1,536/ 65 Int. Cl. Ble 1/02; B65d 3/04 U.S. Cl. 93-80 15 `Claims ABSTRACT F THE DISCLOSURE The present invention relates to a tubemaking apparatus. More specifically, the invention relates to an apparatus for making tubes by helically convoluting strips of tape-material. Such apparatus, by virtue of its novel operation and simple construction, will increase the rate of tube production while decreasing the downtime resulting 4in conventional apparatus of this type from Separation of the strip convolutions and from other causes which will become apparent hereafter.

It is known to construct tubes by helically convoluting one or more strips of tape-material, and by thereafter suitably securing the convolutions together. Such tubes find wide use in a variety of applications, for instance as a core on which rolls of various paper products are wound, such as wrapping paper and paper towelling.

In constructing tubes in this manner it is known to convolute the strip of tape-material, which is treated with an adhesive, about a mandrel and subsequently to pass the thus formed tube to a pressing means which serves to press the convolutions of tape-material against one another, so as to cause them to adhere. However, known tubemaking apparatus of this type suffers from various drawbacks. For example, the convolutions of tape-material have a tendency to separate, frequently by slipping in axial direction of the mandrel, prior to and sometimes even after reaching the pressing means. This usually requires that production be interrupted and the convoluting process of the tape-material about the mandrel be restarted. It will be understood that, once such slippage of the convolutions occurs, it w-ill frequently propagate itself back to the winding station at which the convolutions are applied onto the mandrel. Naturally, if the tapematerial shifts at the point at which it first engages the mand-rel, then the next-following convolution cannot properly be joined to the previous one and a proper tube cannot be produced.

An additional diiiiculty with known tubemaking machines of this type is the fact that it is difficult to produce tubes having relatively thick walls, particularly in view of the fact that in such cases it is necessary to use several strips of tape-material, each one of which must be relatively thick, so that proper positioning and maintaining of the convolutions becomes even more ditlicult because of the resistance of the material.

Taking into account these various problems, it is a general object of the present invention to overcome the above-mentioned drawbacks of the prior art.

A more specific object of the present invention is to provide a tubemaking apparatus in which relative diste t placement of the convolutions of the tape-material on the mandrel is prevented.

Yet a further object of the invention is to provide an apparatus of the type outlined above which will permit the use of tape-material of relatively great thickness without increased danger of relative dislocation of the convolutions formed by such tape-material.

In accordance -with one feature of the invention, and in pursuance of these objects and others which will become apparent hereafter, I provide in a tubemaking apparatus a combination of:

(a) An elongated mandrel for supporting a tube from the inside thereof;

(b) Tube-forming means for forming on said mandrel an axially moving tube consisting of helically convoluted adhesive-coated tape-material; and

(c) A plurality of pressing means spaced in axial direction of said mandrel and engaging axially spaced portions of said tube for compressing successive increments of the moving tube.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. l is a top-plan view of an embodiment of the present invention;

FIG. 2 is a View similar to FIG. 1, showing a lsomewhat diiferent embodiment;

FIG. 3 is a schematic showing of a hydraulic drive means for use with the present invention;

FIG. 4 is a top plan view of the drive means shown in FIG. 3; and

FIG. 5 is an axial end view illustrating another embodiment of the invention.

Discussing now the drawing in detail, and firstly FIG. l thereof, it will be seen that there is shown a mandrel 1 about which there moves a rotating tube 5 which advarices axially in direction of the arrow 5'. Convoluting of the tape-material about the mandrel l is not shown since in itself this is Well known in the art. This takes place in the tube forming means which is indicated in the drawing in FIG. l with a corresponding legend. Tube forming means capable of being utilized for this purpose is disclosed, for instance, in U.S. Patents 1,693,850 and 1,714,541.

Downstream of the tube forming means there is arranged a first pressing means comprising a pair of

rollers

3, 4 which are respectively disposed on opposite sides of the tube 5, and are shown here to be located in a common transverse plane. Guided around these rollers 3, `4 is an endless belt 2 having two stringers, one of which passes by the tube 5 laterally thereof and substantially transversely of the axial extension of the tube ll whereas the other Stringer is convoluted about the tube. The

rollers

3, 4 rotate in direction of the respective associated arrows and consequently the belt Z travels in the direction indicated by the arrows provided thereon.

In the particular embodiment shown in FIG. 1 a second pressing means identical with the rst one is arranged spaced from the irst pressing means in axial direction ofl the tube 5. The rollers of this second pressing means are designated with

reference numerals

3a, 4a and the belt is designated with reference numeral 2a.

As the already formed tube 5 leaves the tube-forming means and moves axially in direction of the arrow 5', the convolutions of tape-material do not yet properly adhere to one another. As, now, each successive increment of the tube passes the iirst pressing means, the tube convolutions are compressed one against the other by the action of the travelling belt 2 which engages the tube 5 on the exterior thereof.

If the tape-material used for producing the tube is coated with a pressure sensitive adhesive, this tirst cornpression would cause bonding of the convolutions to one another. However, although the use of such pressure-sensitive adhesive is possible, it is not common for the production of tubes of this type, for various reasons, one of these being the greater economy of other types of adhesives, particularly the type which requires a certain period of time for setting. It will be clear, on the other hand, that if an adhesive is used which requires some time to set and form a reliable bond, that then the belt 2 of the first pressing means can do nothing more than press the convolutions against one another so as to establish a -good contact, since the adhesive is not yet set when the respective increment of the tube 5 passes beyond the belt 2 in direction of the arrow 5. Thus, there is still a danger that the convolutions might become dislocated with respect to one another, thus resulting in a defective tube.

This tendency is counteracted by the positioning of the second pressing means whose lbelt 2a engages the tube with one of its stringers downstream of the point at which the first pressing means engages it. In accordance with one feature of the present invention the spacing between the second and iirst pressing means will `be so selected that the time interval required for any given increment of the tube to travel from the iirst pressing means to the second pressing means corresponds to the period which the adhesive requires for setting, so that the adhesive will be completely or substantially set by the time the respective increment of the tube reaches the second pressing means. It should be understood that the belt 2a of the second pressing means is provided not only for imparting a iinal compression to the convolutions of the tube 5, but also to counteract any forces which might try to separate the convolutions of the tube downstream of the lirst pressing means, for instance by axial slippage or by unwinding, and which could thus result in production of a damaged tube. In fact, the provision of the second pressing means, by reinforcing the compression of the tube convolutions While maintaining the convolutions against displacement, permits the production of a tube of much -greater resistance to bending or breaking. Furthermore, with this arrangement it is possible to use a larger number of individual strips of tape-material then has been done herebefore, and such strips can be of thinner material than is customary, since the two pressing means assure that the convolutions formed by all of these strips will be tightly pressed together into a tube having a very good resistance to breaking and bending.

The danger of convolution slippage is additionally counteracted by the fact that the endless belts: 2 and 2a are so arranged as to exert pull in opposite directions. This may be achieved by rotating the pairs of

rollers

3, 4 and 3a, 4a in opposite directions. If, however, it is desired to rotate the pairs of rollers in identical directions, then oppositely directed pull can be achieved by having one of the

belts

2, 2a extend crosswise of the other.

In the embodiment shown in FIG. 2, which is otherwise largely similar to that of FIG. 1, the rollers 3 of the first pressing means and 3a of the second pressing means are arranged closer together, as seen with respect to the axial extension of the mandrel 1, than the

rollers

4, 4a of the respective pressing means. This results in a trapezoidal arrangement of the rollers. Also, it will be seen that the not convoluted Stringer of the first pressing means, that is of the belt 2, passes laterally of the tube 5 on one side thereof, whereas the not convoluted stringer of the belt 2a of the second pressing means passes by the tube on a diametrically opposite side thereof. Of course, other arrangements of the rollers and belts are possible, and

of these only one possibility will be mentioned here, namely a star-shaped arrangement of the iirst and second pressing means in which the same are arranged substantially in a common vertical plane. This permits a machine incorporating the present invention to be constructed of shorter axial length than would otherwise be possi-ble. Such an arrangement is shown in FIG. 5 which is believed to require no further explanations, being self-explanatory inasmuch as the various illustrated components are the same as in FIGS. 1 and 2.

Coming now to FIGS. 3 and 4, it will be seen that there is shown therein a drive means suitable for driving the pressing means shown in FIGS. 1 and 2. It is preferred that all

rollers

3, 4 and 3a, 4a of the rst and second pressing means have a common drive. To this end each of the

rollers

3, 4 and 3a, 4a is provided with a huid-driven motor 10. It is to be noted that the roller 4a is not visible in FIG. 3.

In the arrangement shown in FIG. 3, which is by Way of example only, there is provided a gear pump 6 which is connected by a pressure conduit 7 with a feed conduit S communicating with the respective hydraulic motors 10 `of the

rollers

3, 4 and 3a, 4a. A return-flow conduit 9 in the form of a collecting conduit connectors the uid motors 10 and communicates with the gear pump 6, so that iluid fed to the motors 10 through the feed conduit 8 is passed into the return-flow conduit 9 and from there reaches the gear pump 6 for recirculation. A bypass conduit 15 connects the pressure conduit 7 with the return-ilow conduit 9 downstream of the gear pump 6, but upstream of the feed conduit 8. A pressure relief valve 5 is provided in the bypass conduit 15 and is so selected that it will open only upon Huid pressure in the pressure conduit 7 exceeding a predetermined maximum. Down stream of the point at which the bypass conduit 15 communicates with the pressure conduit 7, but upstream of the feed conduit 8, there is arranged a shutoff valve 11 which permits selective opening and closing of the pressure conduit 7 and thereby enable selective establishing of communication between the pressure conduit 7 and the feed conduit 8. This shut-oli valve is here shown as consisting of a rotary gate 13 which engages with its opposite ends arcuate wall portions 14 so that, as the gate is rotated in a sense in which both opposite ends engage the wall portions 14, ow of tiuid through the valve 11 is completely stopped, whereas, when the gate is rotated n a sense in which its end portions move away from the wall portions 14, flow of uid through the valve 11 becomes possible, with maximum ow taking place when the gate 13 extends parallel to the direction of ilow. It should be understood that shut-olf valves of different construction are suitable zfor this purpose and that the one shown and described herein is mentioned by Way of example only.

The operation of the drive will be clear from what has been said before, and from a consideration of the drawing. The gear pump 6, which is designed to pump a somewhat greater volume yof fluid than is required for driving the motors 10, feeds the lluid through the pressure conduit 7 in the direction of the arrow. It the valve 11 is closed, pressure builds up in the pressure conduit 7 to a predetermined level. When this level is exceeded, the relief valve 12 opens and permits escape of iluid through the bypass conduit 15 and into the return-ow conduit 9. In the return-flow conduit 9, the fluid is prevented -from owing in direction towards the motors 10 by the check valves 15 which are installed in the conduit 9, so that the fluid must necessarily return to the gear pump 6. When the gate 13 of shut-olf valve 11 is slowly opened to an increasing extent, the fluid can pass from the pressure conduit 7 into the feed conduit 8 and from there into the fluid motors 10 which thus simultaneously and gradually are accelerated under full load conditions.

It should be pointed out that various modifications are possible and will offer themselves readily to those skilled in the art. Such modifications are intended to be encompassed in the protection sought. It will also be obvious that the invention is suitable for use with strips of tape-material of various types, for instance paper, light cardboard, plastics, metal foil and similar materials.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of a tubemaking apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in tubemaking apparatus, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

I claim:

1. In a tubemaking apparatus, the combination of an elongated mandrel for supporting a tube from the inside thereof; tube-forming means for forming on said mandrel a tube moving axially at a predetermined speed and consisting of helically convoluted tape material coated with an adhesive which is applied in non-set state and requires a setting period for establishing a bond; and pressing means spaced in axial direction of said mandrel and engaging axially spaced portions of said tube for compressing successive increments thereof, said pressing means including a first and a second endless driven belt each having a Stringer forming a convolution about said tube, said adhesive on any increment of said tube being in non-set state when such increment passes said first belt and said second belt being spaced from said first belt downstream thereof by a distance whose traversal by such increment at said predetermined speed requires a time interval corresponding to said setting period.

2. In a tubemaking apparatus, the combination of an elongated mandrel for supporting a tube from the inside thereof; tube-forming means for forming on said mandrel a tube moving axially at a predetermined speed and consisting of helically convoluted tape material coated with an adhesive which is applied in non-set state and requires a setting period for establishing a bond; and pressing means spaced in axial directions of said mandrel and engaging axially spaced portions of said tube for compressing successive increments thereof, said pressing means including a first and a second endless driven belt each having a Stringer forming a convolution about said tube, the Stringer of one of said belts being disposed ou one side of said tube and convoluted about the latter from said one side, and the stringer of the other of said belts being disposed on a diametrally opposite side of said tube and convoluted about the latter from said opposite side.

3. In a tube making apparatus as dened in claim Z, said pressing means further comprising a pair of guide rollers for each of said belts and about which the respective belt travels, one roller of each pair being located on one side of said tube and the other roller of each pair being located on an opposite side of said tube, the rollers located on said other side being farther spaced from one another in axial direction of said tube than the rollers located on said one side.

4. An apparatus as defined in claim 3, wherein said rollers are arranged in a substantially horizontal common plane.

5. A tubemaking apparatus as defined in claim 2, further comprising a pair of rollers associated with each of said belts supporting the same; and drive means counected with said rollers for driving the same and thereby said belts, said drive means including a fluid-operated motor for each of said rollers and a hydraulic system operatively connected with the respective motors for driving the same.

6. An apparatus as defined in claim 5, wherein said hydraulic system comprises a pump, conduit means containing a fiuid and including feed-conduit means connecting said pump with the respective motors for feeding said fiud thereto, return-flow conduit means connecting said motors with said pump for returning said fluid to the latter, by-pass conduit means connecting said return-fiow conduit means with said feed-conduit means upstream of said motors, and adjustable valve means arranged in said feed-conduit means upstream of said motors and downstream of said by-pass conduit means for selectively varying the flow of fiuid to said motors whereby, when said valve means is at least partially open, fluid will flow to said motors and drive the same whereas, when said valve means is closed, fluid will flow through said by-pass conduit means into said return-flow conduit means.

7. An apparatus as defined in claim 6; and further comprising pressure-responsive valve means located in said by-pass conduit means and arranged to open upon the pressure of fluid in said feed-conduit means exceeding a predetermined level.

8. An apparatus as defined in claim 7; and further comprising one-way valve means arranged in said return-How conduit means upstream of the location at which said bypass conduit means communicates with the same, for preventing fiow of fiuid from said by-pass conduit means to said motors.

9. In a tubemaking apparatus, the combination of an elongated mandrel for supporting a tube from the inside thereof; tube-forming means for forming on said mandrel an axially moving tube consisting of helically convoluted adhesive-coated tape material; and a plurality of pressing means spaced in axial direction of said mandrel and er1- gaging axially spaced portions of said tube compressing successive increments of the moving tube, said pressing means including two endless belts each having a Stringer forming a convolution about said moving tube, and a pair of driven guide rollers for each of said belts about which the respective belt travels, said guide rollers of each pair rotating in mutually opposite directions and the pairs of guide rollers being so arranged that said belts define with one another a trapezoidal outline and exert pull on said tube in mutually opposite directions, said pressing means being arranged to define a star shape with one another and being substantially located in a common vertical plane.

10. In a tubemaking apparatus, tube forming means for forming an axially moving unfinished tube which requires for finishing the application of pressure on its outer surface; and pressing means, including two pressing units spaced in axial direction of said moving unfinished tube and comprising respective endless driven belts each having a stringer convoluted about and engaging axially spaced portions of said tube for pressing against successive increments thereof, and means supporting said belts, said pressing units being arranged at circumferentially different angular positions relative to said tube so that the stringers of said endless belts of said pressing units are convoluted about said tube from different sides of said tube.

11. In a tubemaking apparatus as defined in claim 10, wherein said endless belts are driven in a sense in which said stringers convoluted about said tube each travel in the same direction as the other.

12. In a tubemaking apparatus as dened in claim 10, said means supporting said belts including two pair of guide rollers, each associated with one of said pressing units, about which said belts travel, and wherein at least one roller of each pair of guide rollers is driven.

13. In a tubemaking apparatus as defined in claim 10, wherein said tube forming means is operative for forming said tube from helically convoluted adhesive-coated tape material; and wherein the adhesive with which said tape material is coated is of the type which is applied in nonset state and which requires a setting period for establishing a bond.

14. In a tubemaking apparatus as defined in claim 13, wherein said tube moves axially at a predetermined speed; the adhesive on any increment of the tube being in nonset state when such increment passes the upstream one of said belts and the downstream one of said belts being spaced from the upstream one of said belts by a distance whose traverse by such increment at said predetermined speed requires a time interval corresponding to said setting period.

15. In a tubemaking apparatus, tube forming means for forming an axially moving unfinished tube which requires for finishing the application of pressure on its outer surface; and pressing means, including two pressing units spaced in axial direction of said moving unfinished tube and each comprising an endless driven belt each having a stringer convoluted about and engaging axially spaced portion of said tube for pressing against successive increments thereof, and each pressing unit further having a pair of rollers supporting the respective belt, said rollers of the respective pairs of rotating in mutually opposite directions and said pairs of rollers being arranged at circumferentially different angular positions relative to said tube and in such a manner that Said belts dene With one another a trapezoidal outline.

References Cited WILLIAM S. LAWSON, Primary Examiner