US1792081A - Web-tensioning device - Google Patents

Description

Feb. 10, 1931. M. F U CH 1,792,081

WEB TENSIONING DEVICE Filed Feb. 23, 1929 2 Sheets-Sheet 1 INVENTOR MART/W FEYBl/scl-l,

M. FEYBUSCH WEB TENSIONING DEVICE Feb. 10, 1931.

Filed Feb. 23, 1929 2 Sheets-Sheet 2 INVENTOR MART/7V Ffi'VBt/SCH, 3V2 z E Patented Feb. 10, 1931 UNITED STATES PATENT OFFICE MARTINFEYIBUSCH, OF BROOKLYN, NEW YORK, ASSIGNORTO JERSEY MACSHINE CORPORATION, OF HOBOKEN, NEW JERSEY, A CORPORATION OF NEW JERSEY WEB-TENSIONIN' G DEVICE Application filed l'ebruary23, 1929. Serial No. 341,947.

Thepresent invention relates to devices for in connection with paper box manufacturing apparatus of the type wherein a narrow strip of covering material, such as paper, is adhesively coated and supplied to a box wrapping or stripping machine where it is wrapped around the side walls of a box body or ox cover. Ap aratus of this type consists essentially of any suitable gumming machine through which the paper to be gummed is drawn by feeding rollers or a feeding drum, the gumming machine and feeding mechanism operating continuously and delivering the paper to an intermittent feeding mechanism which operates to deliver the adhesively coated paper to the box wrapping machine in proper timed relationship to the wrapping machines cycle of operations. In its passage from the continuous to. the intermittent feeding mechanism the paper is held by a web tensioning roller in a depending loop. As

'heretofore constructed the roller rested with I by a stop. When this occurred the tension on the paper was relieved and the feeding action of the continuous feed was interrupted by various well known devices.

Due to the fact that the continuous feeding mechanism is in motion up to the time the tension is released, the inertia of the moving parts thereof prevents an immediate stoppage of said mechanism and consequently a sli ht excess of paper is always fed after the tension of the web tensioner on the paper is released thus leaving a slight gap between the paper web and the tensioning roller. Therefore when the intermittent feed again becomes operative the paper is pulled with a snapping action against the roller and frequent breakages of the paper strip occur especially when operatmg on narrow strips. This tendency of the paper to break is moreover increased when, as in paper box wrapping apparatus, the paper is coated with a wet adhesive, the moisture of the adhesive penerating the fibres of the paper and materially reducing its tensile strength. Of course such breakages necessitate the rethreading of the machine and therefore a consequent loss of time,-waste of paper and reduction of output.

The principal object of the present invention is to provide anew and improved construction for a web tensioning member by means of which the strains upon the paper due to the sudden jerking thereof, are absorbed and breakage. of the paper is prevented.

Another object of the invention is to provlde means whereby the tension of the device can be readily altered so as to accommodate various widths of webs and give satisfactory results with all sizes.

A further object is to allow for the regulation of the length and'tension of the initially fed section of the paper strip.

The above and other objects will appear more fully from the following more detailed description and by reference to the accompanying drawings wherein Fig. 1 is a side elevation of a portionof a box manufacturmg apparatus to which has been applied an improved tensioning device constructed in accordance with the principles of the invent on; Fig. 2 is an enlarged sectional detail view of a spring clamp; Fig. 3 is an enlarged slde elevation of the web tensioning device shown in several of its operating positions;

Fig. 4 is an enlarged plan view of the device be used in conjunction with paper box machines of the type generally known as box strlppmg or box wrapping machines.

Mounted on the extension frame 20.0f a

box wrapping machine the main part of which is not shown, is a paper reel support 21 on which is wound a reel of paper 22. Disposed above the paper reel 22 and secured to the frame 20 is a glue pot 23 in which are rotatably mounted the glue rolls 24, the lower roll dipping into the glue and transferring it to the upper roll which applies the adhesive to the paper. The web of paper 25, as it is unwound from the reel 22. passes over the guide 26 and thence under the idler roll 27 being held by the latter in contact with the up er or glue applying roll 24.

djacent to the glue pot 23 and secured to the frame 20 is a feed wheel support or bracket 28, having rotatably mounted on the upper part thereof a continuously rotating paper feeding wheel or drum 29. is journaled in the bracket 28 and has secured to one end thereof a pulley 31. On the other end of the shaft 30 is secured a pulley 32, which is continuously driven from the box wrapping machine by the belt A belt 34 is trained about the pulley 31 and a pulley 35 secured to the shaft 36, which is journaled in the upper part of the feed wheel support 28 and to which shaft is also secured the paper feeding drum 29.

A pair of web supporting, transversely extending, guide bars 37 and 38 are secured at spaced intervals above the frame 20. Located between the said guide bars is the web tensioning mechanism which, as shown, may be constructed as follows: Loosely mounted in a pair of bearing bosses 39 (see Fig. 4) of the main frame 20 is a shaft 40 to which is rigidly secured an arm or lever 41. The free lower end of the arm 41 has pivotally secured thereto, as by a pin 42, a secondary arm 43. The latter is preferably constructed as a two armed lever having one end forked as at 44, and extending rearwardly, while the other end 45 extends forwardly and downwardly below the lever 41 and has secured to it one end of a tension spring 46. Mounted in the forked end 44 of the secondary arm 43 is a pin 47 on which is rotatably mounted a roll 48, which as shown in Figs. 1 and 3 rests in the depending loop of the paper web 25, that extends from the feed drum 29 to the intermittent feeding mechanism presently to be described.

The free end of the arm 41 is provided with the two lugs 49 and 50. in which are mounted adjusting screws 51 and 52. respectii ely. lock nuts 53 and 54 being provided for holding said screws in adjusted position. The screws 51 and 52 are so mounted as to engage the end 45 of the secondary arm 43 at certain points in its oscillatory motion thereby delimiting the movement of said arm.

The tension spring 46 which as pointed out above has one end connected to the projection "15 of the secondary arm 43, has its other end secured to an adjustable clamp 55 mounted for slidable. longitudinal adjustment on the A shaft arm 41. In order to prevent the clamp 55 from being disengaged from the arm 41 during adjustment the latter is provided with lateral ribs 56 which extend longitudinally along the sides of said arm, and said clamp is formed with a yoked end which engages over said ribs as shown best in Fig. 2. One of the legs of the yoked portion of the clamp 55 has screwed therein a thumb screw 57 which is adapted to securely hold the clamp in any given position.

To the upper pivoted end of the arm 41 is secured a depending lug 58, in which is mounted an adjustable stop screw 59 provided with a lock nut 60. The projecting end of the screw 59 is adapted to engage the frame 20 thereby limiting the downward movement of the arm 41.

The shaft 40 as shown in Fig. 4, preferably has one end extended and to such end is rigidly secured a lever 61 having fixed thereto a bar 62 on which is slidably mounted a weight 63, provided with a thumb screw 64 adapted to secure the Weight 63 in adjusted position longitudinally of said bar.

Supported on the main frame of the box wrapping machine is a reciprocating slide 65 of the usual intermittent feeding mechanism. The slide 65 is actuated from the wrapping machine by a rod 66 which reaches from the stripping machine and has one end pivotally connected to a pin 67 adapted to be adjustably clamped in the slot 68 of the lever 69. The lever 69 is pivotally mounted on a pin 70 secured in a bracket 71 mounted on the main frame 20. To the upper end of the lever 69 is attached a connecting rod 72 which transmits the motion of the lever 69 to a double armed lever 73 rigidly secured to a pin 74. The pin 74 is pivotally mounted in an upwardly extending lug 75 integrally associated with the slide 65. In the lower arm of the lever 73 is a curved slot 76, into which projects a pin 77, secured to the lug 75; said pin co-operates with said slot to limit the clockwise motion of the lever 73. On the pin 74 is also rigidly secured an arm 78 on which is mounted a paper engaging dog 79.

Directly behind the slide 65 a paper stop cam 80 is mounted on a bracket 81 which bracket also serves as a support for the pa or guide bar 38 hereinbefore referred to. The bracket 81 is supported by a bar 82. secured in the frame 20. It will be seen from the above described construction that the depending loop of the paper web 25, in which the roll 48 rests, will be placed under a tension produced by the effective weight of the roll 48, secondary arm 43 and arm 41 as determined by the setting of the counterbalancing weight 63.

The operation is as follows: Assuming that the paper strip or web 25 has been fed or threaded through the machine. that the slide 65 is in its rearward position shown in Fig. 1

with the paper engaging .dog out of contact with the web and with the web held in the position shown, by the stop cam 80; the operative then starts the driving means (not shown) of the box wrapping machine which through belts 33, and 34 and the parts 32, 30,

31, 35, 36 described above, sets the feed wheel 2-9 in continuous counterclockwise rotation.

When the paper is initially threaded through the machine the roll 48 is in its lowermost position, with the stop screw 59 in engagement with the frame 20, therefore no tension is placed on the paper by the roll and as a result the rotation of the feed drum 29 will not be effective to produce any feeding of the web because the latter will not be held with suflicient frictional engagement against said drum.

As the wrapping machine starts to function the rod 66 and slide will be drawn toward the left by suitable actuating mechanism in the wrapping machine. When this occurs the rod 72 will swing the lever 7 3 upon the pin 74 and the paper engaging dog 79 will be forced downwardly into contact with the paperstrip. As the slide 65 continues to move toward the left a pull will be exerted on the paper strip 25 tending to feed it into the wrapping machine. The initial pulling of the paper strip is relatively slow and even, and this movement of the strip will tend to decrease the length of the depending loop of the web 25, and to raise the roll 48.

The spring 46 will be so adjusted according to the width and strength of the paper being used that the secondary arm 43 will swing upon its pivot 42, as indicated by the lower dotted showing in Fig 3, when a pull or tension, less than that which would cause breakage, is plac'ed upon the paper. Therefore the initial pull exerted by the intermittent feeding mechanism tending to raise the roll 48 produces first a swinging of the secondary arm 43.

As the secondary arm of the tensioning device 'is so swung the weight-of the arm 43 with the attached parts and the spring 46 effects a tension in the strip 25 causing said strip to frictionally engage the feed wheel 29.

Immediately after the paper strip is fed into engagement with a box to be stripped, in the wrapping or stripping machine, the machine operates to start the box rotating. The extent of feed of the paper strip 25 by the intermittent feeding mechanism before the box in the machine starts to rotate is small, andas the strip is coated with a more or less slippery adhesive it is very desirable to have the initial tension in the paper strip small so as not to cause the paper strip to slip out of engagement with the box when said box starts to rotate. This small initial tension is accomplished by having the small spring 46. This arrangement allows the paper strip 25 to be wrapped around the corner of the box before the secondary arm 43 reaches the limit of its working stroke, thereby giving the paper strip suflicient contact with the box before theftension is increased.

Inasmuch as the greater number of boxes operated upon are oblong it will be readily understood that the tensile stresses and travelling velocities of the paper stripwill vary greatly. As the box continues to rotate the paper will be consumed more ra idly and the tensionin device will move t ward the dot and dash ine position (Fig. 3). Due to this, added tension will be set up in the strip and said strip will be more rapidly fed by the drum 29 owing to the increased pressure and thereby increased frictional force between the strip 25 and said drum. This feeding action of the drum will vary in direct proportion to the ten-sion in the web, consequently the feeding action will be greatest when the supply demanded is greatest.

In actual operation, the adjustments of the spring 46 and weight 63 are such that when the secondary arm 43 reaches a point about half way between its two limiting positions, as determined by thesetting of the adjusting screws 51, 52, the tensioning effect of the arm 41 begins to be felt. By adjusting the parts in this manner the resilient shock absorbing action of the spring 46 is available through i all parts of the stroke of the lever 41. In other words, if a sudden pull occurs in the strip 25 after the arm 41 has left its lowest position the resilient action of the spring 46 will absorb the jerk, and prevent the strip 25 from tearing which would otherwise occur if a dead weight were used to maintain the depending loop.

The construction of-the tension device is such that the abrupt pulls in the paper strip will be absorbed by the secondary arm 43 and spring 46, the long even pulls being properly tensioned by the action of the arm 41 and weight 63. It will therefore be readily seen that the paper strip will at all times be placed under the proper amount of tension to secure the most effective feeding action of'the feed wheel 29 and that due to the exceedingly flexible action of the secondary arm 43, the snapping or tearing of the strip present when only a single tension arm is used will be eliminated.

In casewide strips of paper are fed and the tension desired in the strip is to be increased, this may be accomplished by moving the weight 63 toward the shaft 40 thereby reducing the counterbalancing effect of said weight. The amount of paper kept in the depending loop or bight of the web 25 may be regulated by adjusting the stop screw 59. The employment of the various adjust.-

ments indicated, with, a device constructed in accordance with the principles of the invention results in greatly extending the range of the machine which is of marked advantage especially where a great variety of paper widths is used.

Having thus fully described my invention What I claim as new and desire to secure by Letters Patent is as follows:

1. In a web tensioning device, means for applying to a web an initial state of tension and means operative subsequently for applying a secondary state of tension to said Web.

2. In a web tensioning device, means for applying to a web an initial light resilient tension and means operative subsequently for applying a secondary comparatively heavy resilient tension to said web.

3. In aweb tensioning device, wherein the web is fed in a depending loop or bight, means to engage said depending loop of said web and hold it under tension, said means including devices operating in succession for automatically applying varying tensions to the web as the depth of said depending loop varies.

4. In a web tensioning device, means to engage the depending loop of a web, for automatically applying tension thereto, said means including resilient devices for causing the effective tensioning force to be increased and diminished as the depth of said loop decreases and increases respectively.

5. In a web tensioning device, an arm pivotally supported at its one end, a second arm pivotally mounted in the free end of said 'lirst named arm, a roll rotatably mounted on said second arm and adapted to engage the depending loop of a web and means to limit the oscillatory movement of said second arm, relatively to said first named arm.

6. In a web tensioning device, an arm pivotally supported at its one end, a second arm pivotally mounted in the free end of said first named arm, a roll rotatably mounted in said second arm adapted to engage the depending loop of a web, means to limit the oscillatory movement of said second arm and resilient means for normally urging said second arm toward one of the limits of its oscillatory movement.

7. In a web tensioning device, an arm pivotally supported at its one end, a second arm pivotally mounted in the free end of said first named arm, a roll rotatably mounted on said second arm adapted to engage the depending loop of a web, adjustable means adapted to limit the oscillatory movement of said second arm, resilient means for urging said second arm toward one of the limits of its oscillatory movement, and adjustable means to alter the effective turning moment of said resilient means on said second arm.

8. In a Web tensioning device, in combination, an arm pivotally mounted at one end thereof, a second arm pivotally mounted on the free end of said arm, a roll rotatably mounted in said second arm adapted to engage the depending loop of a Web and adjustable means for regulating the effective tensioning force of said arms on said web.

9. In a web tensioning means, a lever having a roller mounted therein for engagement with a depending loop of a Web, said roller exerting on said loop and web a predetermined efiective pressure, adjustable means for varying said effective pressure, and. a resilient shock absorbing device interposed between said roller and lever for permitting said roller to yield whenever saidv Web is placed under tensions exceeding that produced by said effective pressure.

10. A web tensioning device as set forth in claim 9, in which means are provided for adjusting said shock absorbing device to permit it to yield under different tensions.

11. A web tensioning device as set forth in claim 9 in which adjustable stops are provided .for limiting the movement of said shock absorbing device relatively to said lever.

In testimony whereof I have hereunto set my hand.

MARTIN FEYBUSCH.

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