Machine For Rolling Up Flexible Articles

Abstract

A machine for rolling up soft flexible articles comprises a non-circular rotating spindle, a first roller means below the spindle, and second roller means mounted to be brought toward and then over the spindle to bend over the spindle the end of a flexible article gripped between the spindle and first roller means.

Description

SUMMARY OF THE INVENTION

This invention relates to a machine automatically rolling up an article made of a flexible material, for example a sanitary napkin.

It is well known that sanitary napkins now in use comprise layers of adsorbent materials such as cotton or cellulose pulp.

These products are in the form of a strip about 20 cm long and it is desirable, in view of their intended use, to be able to package them in a container having a minimum volume.

This invention relates to a machine for rolling such sanitary napkins up while confining them within a small volume without impairing their initial qualities of flexibility and adsorptive power, which they again possess immediately after being unwound.

It is, however, obvious that while the machine will be hereinafter described with reference to its use for rolling up sanitary napkins, it may also be used to roll up any material having analogous characteristics.

It is an object of the present invention to provide as a new article of manufacture a machine for winding up on itself an article analogous to a sanitary napkin, which machine is characterized by the fact that it comprises in combination a spindle having a non-circular section and adapted to be driven in rotation and a first pair of rollers mounted side by side and having their axes parallel to the axis of said spindle. The first pair of rollers is positioned substantially below the level of the spindle and may be kept in a position spaced from that spindle or resiliently biased toward said spindle. A table is positioned near the first pair of rollers at substantially the same level as that of the upper part of the rollers of the first pair when maintained in their position spaced from the spindle. A stop is mounted on the other side of the first pair of rollers so as to be located opposite the space between the spindle and the first pair of rollers. A second pair of rollers have their axes parallel to each other and to those of the spindle and are mounted on an arm which cooperates with means for moving the second pair of rollers between a position spaced from the spindle and a position substantially above the spindle in which the second pair of rollers may freely approach or depart from said spindle.

The machine according to the invention advantageously comprises ejector means for releasing the wound-up napkin from the spindle and inserting it into its container.

In a particular embodiment of the invention the second pair of rollers is mounted at one end of an arm, the other end of which is pivotally attached to another lever which pivots about a fixed point and is actuated by a cam which longitudinally displaces said arm. A roller situated on said arm between the pivot point and the second pair of rollers cooperates with an inclined ramp so that during the displacement of the arm the second pair of rollers rises into a position above the spindle.

In one embodiment of the invention the lever to which the end of the arm which supports the second pair of rollers is attached is actuated by a cam, the movement of which displaces the second pair of rollers at an opportune moment.

In a particular embodiment of the invention the first pair of rollers is mounted upon a supporting rod so as to be vertically slidable toward and away from the spindle, a first draw-spring being provided to constantly bias the first pair of rollers toward the spindle.

A lever having two arms and pivotally mounted to swing about a fixed point has the end of one arm resting on a member fixed to the supporting rod for the first pair of rollers. This lever is actuated by a second draw-spring the strength of which is sufficient to overcome that of the first spring which tends to bring the first pair of rollers toward the spindle. The other arm of this two armed lever is provided with a roller bearing against a cam which, in one position permits the second draw-spring to operate (thus maintaining the second pair of rollers spaced from the spindle), and in another position permits the first draw-spring to operate, which resiliently repels the first pair of rollers in the direction of the spindle.

The operation of the machine which has just been described is as follows:

In a first step, the first pair of rollers is kept in a position spaced from the spindle so that the upper part of the rollers of the first pair is substantially in alignment with the table which is to receive the napkin which is to be wound-up.

The end of a napkin is then introduced into the space between the spindle and the first pair of rollers, the end of the napkin being brought up against the stop and the napkin being then supported by the table.

In the next step, the retaining means for the first pair of rollers is released so that these rollers are then urged upward to elastically grip the part of the napkin near its end between the spindle and the first pair of rollers.

In the course of this movement the end of the napkin is bent upward as a result of the gripping.

During the next step, the second pair of rollers is displaced, first in the direction of the spindle and then upwardly, so that the rollers reach a position above the spindle resting on the end of the napkin. In the course of this movement the second pair of rollers lowers the end of the napkin above the spindle and holds it in this position by the weight of the rollers and the members which support them or in response to any biasing means provided.

The spindle is then rotated in the direction which winds up the napkin from the end which is already engaged. The napkin is then automatically rolled up about the spindle while being compressed by the first pair of rollers which is biased by the first draw-spring. The force exerted by this spring may be adjusted to determine the degree of compression imparted to the napkin.

When the winding up has been completed ejector means slides the napkin axially off the spindle and introduces it into the container in which it will be retained in the rolled-up state while compressed as has just been described.

According to one embodiment of the invention the ejector means for the wound-up napkin consists of a flange encircling the spindle located at the base thereof during the winding up step. This flange is then displaced axially along the spindle to push the wound-up napkin off and introduce it into its container.

Advantageously the container, for example, a box, may be positioned by means such that a receiving cone into which the wound-up napkin enters is encountered during the displacement of the flange.

In order that the invention may be better understood a preferred embodiment thereof, taken purely by way of illustration and example, will now be described, with reference to the accompanying drawings, in which:

FIGS. 1, 2, 3 and 4 each show a schematic sectional view of an embodiment of a machine according to the invention during four successive steps in its operation; and

FIG. 5 is a schematic view from the top showing the operation of the ejector means.

It will be seen that the spindle 1, which in the instant case is a rod having a square cross-section, but which might have another non-circular section, such as a rectangular or triangular section so long as it is capable of frictionally entraining the napkin. This spindle 1 is mounted on bearings at one end only, with the other end left free, and is fixed to a shaft which may be rotated in the direction of the arrow F.

The drawing also shows the first pair of rollers 2 which are mounted as idlers on a support 3 which is attached to a rod 4 which slides vertically in the bearings 5 and 6, which are schematically shown. Means not shown on the drawings prevents rotation of the rod 4 with respect to the bearings so as to keep the axes of the rollers 2 parallel to the axis of the spindle 1.

A first spring 7 inside the bearings 6 constantly biases the rod 4 to urge it upwardly.

A stop 8 fixed to a regulating screw 9 makes it possible to vary at will the force exerted by the spring 7 on the rod 4. A lever having two arms 10 and 11 pivotally is mounted at 12 on the framework of the machine. The end of the arm 11 is fork-shaped and engages the two pins 13 fixed to the rod 4.

A second spring 14 is hooked at a fixed point 15 on the framework of the machine and acts on the arm 11 of the lever to draw it downwardly.

The strength of the spring 14 is such that when the lever 11 is free, the spring 7 is compressed and the rollers 2 are brought into their lower position, with the support 3 engaging the bearing 5.

The other arm of the lever 10 carries a roller 16 at its end. This roller cooperates with a cam 17. When the roller 16 engages the portion 17a of the cam the action of the spring 14 maintains the rollers 2 in the position shown in FIG. 1.

On the contrary, when the roller 16 engages the portion 17b of the cam 17, the arms 10 and 11 swing and the spring 14 no longer holds the rollers 2 down. The rod 4 is then urged upwardly by the spring 7 (See FIGS. 2, 3 and 4).

The drawing also shows rollers 18 of the second pair which are mounted at one end of a forked arm 19, the other end of which is pivotally attached at 20 to one end of a T-shaped lever, which pivots about a fixed point 21 on the machine. In the middle of the arm 19 is a roller 22 which rides on an inclined ramp 23 on the framework of the machine.

The arm 24a of the T-shaped lever is constantly drawn downward by a draw-spring 25, one end of which is connected at 26 to the framework of the machine.

The arm 24b, diametrically opposite the pivot point 20, carries a roller 27, which engages a cam 28.

In the position shown in FIG. 1, in which the roller 27 rests on the part 28a of the cam 28, the spring 25 acts on the arm 24 24a to draw the arm 19 toward the left, together with the pair of rollers 18 which are carried thereby. In this position the rollers 18 are substantially in alignment with the spindle 1 as shown in FIG. 1.

On the contrary, when the roller 27 engages the surface 28b of the cam 28 the arm 19 is biased to the right, as is shown in FIGS. 3 and 4. In the course of the movement of the arm 19 to the right, the roller 22 rests on the ramp 23 which lifts the rollers 18 at the same time that they approach the spindle 1. When the movement to the right has been completed, the rollers 18 are positioned thereabove.

In the illustrated embodiments, the arm 19 is mounted to swing freely about the pin 20, so that the assembly consisting of the rollers 18, the roller 22, and the arm 19 rests by its own weight either on the napkin, through the rollers 18, or on the ramp 23, through the roller 22.

The drawing also schematically shows table 29, the height of which may be regulated by the screw 30 which passes through oblong orifices 31 in a plate fixed to the table 29, so as to be positioned substantially at the level of the upper part of the rollers 2, when these rollers are in their lower position as shown in FIG. 1.

The drawings also schematically show the stop 32 which is located opposite the space between the spindle 1 and the upper part of the rollers 2. The position of this stop determines the length of the napkin which is engaged during introduction of the napkin between the spindle 1 and the rollers 2.

In the illustrated embodiment, stop 32 is formed on the member which forms the ramp 23 but it is obvious that in another embodiment the stop 32 could be provided in any suitable manner.

It is, however, clear that the table and the stop are preferred, but not indispensable components of the invention. For instance, it would be possible to place and hold the napkin during the course of rolling up without utilizing the table and the stop, but this would be more inconvenient.

The drawing also shows a switch 33 the control roller 34 of which cooperates with a cam 35.

When the roller 34 engages the vertical part 35a of the cam 35 the switch opens the circuit controlling the spindle 1, which is not then driven.

On the other hand, when the roller 34 engages the inclined part 35b of the cam, the contact 33 is closed and the spindle 1 is driven.

FIG. 5 is a top plan view of the machine which has just been described. The spindle 1 is fastened to the shaft 36, which is itself connected to a motor for driving it. The right end of the spindle 1 is unsupported.

FIG. 5 also shows the forked end of the arm 19 which supports the rollers 18, as well as the roller 22 which rests on the ramp 23 to raise the rollers 18. The table 29 is also shown.

This figure also schematically shows a flange 37 which encircles the spindle 1 and is supported by a sliding member 38 mounted in bearings 39.

The end of the member 38 is connected by a connecting rod 40 to the piston 41 of a pneumatic or hydraulic cylinder and biased by a spring 42.

It will be appreciated that, under these circumstances, when fluid under pressure is applied to the piston 41 the flange 37 is driven to the right.

FIG. 5 also shows in section a napkin 43 which is wound-up on the spindle.

The side 44 of the machine, which is located at the free end of the spindle 1, is provided with an opening 45 equipped with a funnel 46 which is slightly frusto-conical and admits the napkin 43 in the compressed state.

The figure also schematically shows a carton 47 for receiving the napkin 43.

The machine according to the invention also comprises other components of a conventional type which make it possible to carry out in the desired succession the various movements necessary to wind up the napkin.

These conventional means may, for example, consist of cams such as the cam 17 and 28 which have been described (and which in the present case turn in the direction indicated by the arrows). Analogous cams mounted on the same shaft may also be used to control different switches for completing electrical circuits necessary to carry out various operations.

No further information on the subject of these means is given, since they are conventional and may be replaced by any other equivalent means for carrying out the same steps.

The operation of the machine will now be described.

At the beginning, the various components are in the position shown in FIG. 1. At this moment the operator places a napkin 43 on the table pushing it so that its end comes up against the stop 32, with the napkin between the spindle 1 and the rollers 2. The operator then presses an electrical control button to initiate the automatic execution of the following cycles:

By rotation of the cam 17 the arm 11 pivots about the axis 12 to liberate the rod 4 which is urged by the spring 7 to grip the napkin between the spindle 1 and the rollers 2.

The various members are then positioned as shown in FIG. 2.

It will be noted that end of the napkin 43 tends to rise up because of the compression and also because of the fact that the napkin is gripped between the spindle and the two rollers on opposite sides of the spindle.

In the following step the rotation of the cam 28 causes the progressive displacement of the arm 19 toward the right thus urging the rollers 18 away, while lifting them through the roller 22, which travels on the ramp 23.

When the arm 19 has been moved all the way toward the right, the members are in the position shown in FIG. 3 and the two rollers 18 at above the spindle 1 rest on the end of the napkin 43 which is thus slightly compressed.

In the embodiment illustrated, no means has been provided for urging the rollers 18 down on the end of the napkin other than the weight of the assembly consisting of the arm 19, the roller 22 and the rollers 18, but this weight may of course be increased by supplying resilient biassing means, or by adding a supplemental weight acting on the lever 19.

At this moment a cam not shown in the drawings (but which may be, for example, attached to the shaft which drives the cam 17 and 28) begins to rotate the spindle 1 in the direction of the arrow, that is to say, in the direction which tends to wind up the napkin about the spindle.

The napkin then slides on the table 29 and rolls-up around the spindle while being compressed by the spring 7.

The degree of compression of the napkin may then be determined by acting on the adjusting means 8 which varies the force exerted by the spring 7.

When the winding up has been completed, the contact 33, the roller 34 of which rides on the part 35a of the cam, stops the spindle. The function of the contact 33 is to insure that the napkin, when in the wound-up state, has a minimum diameter, before permitting its passage to the following step.

In effect it has been found that, during certain operations of the machine, the napkin does not start its winding up promptly and does not consequently attain any substantial diameter around the spindle. The presence of the contact 33 thus makes it possible to insure that the winding up of the napkin on the spindle has been effectuated under satisfactory conditions.

From this moment a switch causes fluid to be supplied under pressure to the hydraulic cylinder 42, which displaces the flange 37 to the right (FIG. 5). The napkin 43, still in the compressed state, is then urged by the flange 37 into the funnel 46 and thus introduced into the carton 47, one end of which has already been placed around the funnel 46.

The next operation consists in returning the different components of the machine to the position shown in FIG. 1.

The return of the flange 37 from the position shown in FIG. 5 is produced by any suitable resilient return means, or by using a double acting hydraulic cylinder 42.

It will be seen that the machine which has just been described makes it possible to package sanitary napkins in a particularly simple and economical manner when these napkins must be rolled up under a pressure sufficient to reduce their volume to a maximum but insufficient to impair their essential properties when they are unrolled.

It will of course be appreciated that the embodiment which has just been described has been given purely by way of example and may be modified as to detail without thereby departing from the basic principles of the invention.

In particular, it is obvious that the rollers 2 could be rotated at the same time as the spindle 1 and that this might facilitate the winding up process.

Of course only one of these rollers might be driven.

This is also true of the rollers 18, although rotary action of these rollers has a less important effect upon the winding up process.

The movements of the various members may also be brought about in different ways. While, in the embodiment described, the spindle remains in a fixed position while the rollers move toward and away from the spindle, it is obvious that a machine could be devised in which the rollers are kept in a stationary position and the spindle moved toward and away from the rollers.

Moreover, it will be appreciated that the rollers 18 may be mounted on a support other than the arm 19 which has been described, the essential condition being that the rollers 18 be capable of raising the end of the napkin on the spindle so as to assure its being held during the winding up process.

Likewise it is clear that, without departing from the basic principles of the invention, the two rollers 18 might be replaced by an assembly comprising a different number of rollers, that is to say either by a single roller of larger diameter or by an assembly of more than two rollers. Likewise the winding up could be carried out by using a group of three rollers instead of a pair, as is the case of the device which has been described.

Finally, it is obvious that the movements of the different members may be produced by other known means than those which have been described and illustrated on the drawings.

Claims

What is claimed is:

1. Machine for winding up a soft, flexible article which comprises in combination a rotatably-mounted spindle of non-circular section, first roller means mounted at one side of said spindle to turn about an axis parallel to said spindle, pressure means for resiliently urging one of said spindle and first roller means toward the other, second roller means mounted at a second side of said spindle to turn about an axis parallel to said spindle and lying in a plane transverse to a plane containing the axis of said spindle and passing through said first roller means, and means for moving said second roller means first toward the center of said spindle and then around said spindle to the opposite side thereof from said first roller means, thereby bending about said spindle an article gripped between said first roller means and said spindle.

2. Machine as claimed in claim 1 in which said means for moving said second roller means comprises an arm mounted for longitudinal displacement and carrying at one end said second roller means, third roller means carried by said arm, and a stationary ramp on which said third roller means rides, and by which said arm is guided when moving said second roller means around said spindle.

3. Machine as claimed in claim 2 comprising a pivotally mounted lever to which the end of said arm remote from said second roller means is pivotally attached, and comprising a rotating cam which swings said lever and thereby moves said arm longitudinally.

4. Machine as claimed in claim 1 comprising first spring means biassing said first roller means toward said spindle, second spring means stronger than the first, lever means through which said second spring means is connected to bias said first roller means away from said spindle, and cam means for swinging said lever means in a direction which relieves the bias imposed by said second spring means on said first roller means.

5. Machine as claimed in claim 1 comprising a table adjacent the gap between said spindle and said first roller means for supporting an article gripped therebetween.

6. Machine as claimed in claim 5 comprising a stop adjacent the gap between said spindle and said first roller means on the opposite side thereof from said table.

7. Machine as claimed in claim 1 comprising an ejector means for removing an article which has been wound-up on said spindle.

8. Machine as claimed in claim 7 in which said ejector means comprises a flange encircling said spindle and means for reciprocating said flange longitudinally of said spindle.

9. Machine as claimed in claim 8 comprising a frusto-conical guide adjacent one end of said spindle and positioned to receive a wound-up article ejected from said spindle by said ejector means.

10. Machine as claimed in claim 1 in which said spindle is mounted for rotational movement only and said pressure means urges said first roller means toward said spindle, against the resistance of said article when gripped between said roller means and spindle, said machine comprising a control switch connected to control the rotation of said spindle and cam means responsive to the position of said first roller means connected to open and close said switch as said first roller means moves forward and away from said spindle, in dependence on the thickness of the coils of said article.

11. Machine as claimed in claim 1 in which at least said first roller means comprises a pair of rollers mounted on a common support to rotate about parallel axes.

12. Machine as claimed in claim 1 in which each of said roller means comprises a pair of rollers mounted on a common support to rotate about parallel axes.