US3016009A - Adjustable equal spacing device - Google Patents

Description

Jan. 9, 1962 F. s. TOBEY 3,016,009

ADJUSTABLE EQUAL SPACING DEVICE Filed April 19, 1960 4 Sheets-Sheet 1 INVENTOR FREDERIC S. TOBEY ai/fd/fi ATTORNEY Jan. 9, 1962 Filed April 19, 1960 F. S- TOBEY ADJUSTABLE EQUAL SPACING DEVICE I 4 Sheets-Sheet 2 ATTORNEY Jan. 9, 1962 F. s. TOBEY ADJUSTABLE EQUAL SPACING DEVICE 4 SheetsSheet 4 Filed April 19, 1960 INVENTOR 'FREDERIC s. TOBEY Bv I fo m

AT TORNEY United States Patent 3,016,009 ADJUSTABLE EQUAL SPACING DEVICE Frederic S. Tobey, Walpole, Mass, assignor to H.

Brady Co., Milwaukee, Wis., a corporation of Wisconsin Filed Apr. 19, 1960, Ser. No. 23,232 9 Claims. (c1.101 22s The present invention relates to rotary equipment for making periodic impressions upon a continuous web of material, such as die-cutting devices, rotary presses used for printing on such material, or combinations of both die-cutting and printing devices. In particular, the present invention relates to a means of providing uniform spacing between die cuts and/ or printed impressions made upon a continuous web when the printing plate or cutting die itself is the sole means of forwardly moving the web, and which invention further provides a means of accurately varying the spacing between die cut portions and/ or printed portions, in order that the die cuts or printed impressions may, at the will of the operator, be caused to overlap, to be spaced a maximum distance apart, or to be spaced at any point between these two extremes.

In devices, such as rotary presses, in which a cutting die, or a printing plate, or a cutting die combined with a printing plate, constitutes the sole means of pulling or forwardly moving a continuous web of material to be printed or to be die cut or both, such as in a machine for die-cutting labels from an adhesive backed paper or web temporarily adhering to a releasable backing member, the leading edge of the plate or die makes contact with the web, squeezing it against a cylindrical platen and causing it to move forward until the trailing edge of the plate or die is reached. At this point the plate or die will leave the web, and the web will stop moving and will remain at rest until the leading edge of the plate or die (which is continually revolving) again makes contact with it. This action will ordinarily provide some spacing be tween the printed impressions or die cuts. For a number of reasons, however, the spacing will often not be uniform, as desired. Since the web has forward motion, its own inertia will cause it to continue to move, more or less, for a period after the plate or die has left it. More important, and especially in the case of a cutting die, the web will continue to follow the plate or die for a short space of time after the trailing edge has left the platen, and this period of time will vary between one impression and another, with the result that spacing between the impressions will be varied accordingly.

On many occasions it is of great importance that the spacing between the die cut portion to be uniform, as for example when labels are cut and/or printed from a continuous web and are to be applied automatically to an object on a production line basis, either immediately after being printed, and as they emerge from the press, or at some time later, in a separate dispensing machine.

Among the various objects of the present invention is the provision of an improved die-cutting device which makes possible the achievement of uniform spacing between die-cut objects to within a few thousandths of an inch, and at the same time provides a means of infinitely varying, at the will of the operator, this spacing within its maximum limits.

Other objects and advantages will become more readily apparent from the following description and the accompanying illustrative drawings, in which:

FIG. 1 is a fragmentary perspective view of operating components assembled in accordance with one embodiment of the present invention, and illustrated in cooperative relationship in their various functions to provide a combined die-cutting means and means for forward advancement of a continuous web of material comprising an adhesive backed laminate in temporary adherence with a releasable backing strip;

FIGS. 2 and 3 are fragmentary vertical sectional views of the components in operating relationship with a continuous web of material, and illustrating the position of such components during various stages of their operation;

FIG. 4 is a fragmentary sectional View taken along lines 4-4 of FIG. 2;

FIG. 5 is a fragmentary detailed view, partially in section, of an adjustment element of the present invention taken along line 55 of FIG. 2;

FIG. 6 is a perspective view illustrating a continuous web of laminated, adhesive backed material in releasable mounting relationship with a Web-like liner or backing member, in which equal spacing between die-cut portions has been accomplished by the die-cutting arrangement;

FIG. 7 i a perspective view of a continuous web of material similar to that of FIG. 6 wherein an adjustment has been made of the apparatus to provide a series of diecut labels, or the like, wherein the leading and trailing edge of the die are caused to define labels in adjacent relationship with no spacing therebetween;

FIG. 8 is a vertical sectional view, similar to the views of FIGS. 2 and 3, and illustrative of another embodiment of the present invention.

It will be apparent, with reference to the drawings, and especially to the embodiment of FIGS. 1-5, that only the essential operating components of the present invefi:

tion are illustrated. The components are readily adaptable for use with conventional die-cutting and printing devices and much of the mechanism relating to such devices has been eliminated from these figures for simplicity of description. The present device is useful when used in connection with a web of plain paper or other material having no adhesive, or an unlaminated web having a water or other solvent soluble adhesive. However, the device is particularly applicable for use with a laminated material comprising a continuous web-like strip of material, generally denoted by the reference numeral 10, comprising an upper laminate 11 to be die cut and/or printed and which may have, on its underside a layer of pressuresensitive adhesive protected by a releasable liner 12, such as paper coated with a conventional release composition. A rotary cutting die 13, having a recessed surface 14 (see FIGS. 2 and 3) and relatively sharp marginal cutting edges comprising a leading edge 15 and trailing edge 16 rising from the surface 14, is provided as a means of die-cutting desired configured portions, such as labels 17 (see FIGS. 6 and 7) from the Web-like material 10. The present invention contemplates the provision of means for adjusting and maintaining uniform the spaced apart areas 18 separating each of the labels 17 (see FIG. 6). It is conventional, in many cases, to provide a resilient printing pad of rubber or the like (not shown) in combination with the die 13 and in seating engagement with the recessed surface area 14 defined by the marginal cutting edges, to permit simultaneous printing upon the label as it is being cut from the web. The printing pad will have the desired printing identification in the usual raised fashion, andmeans (not shown) are provided for the pad to be inked as it is rotated along with the die 13. The particular pad and inking means does not form a part of the present invention.

It will also be apparent that a rotating printing device may also, at times, be used alone (not shown), without the die 13, and will, because of frictional forces, act to advance the web 10 as spaced indicia are impressed thereon. The equal spacing device of the present invention has equal application to such embodiment.

The cutting die 13 is attached directly to a rotating or revolving shaft 20 (see FIGS. l-3). Prime mover means for rotating the shaft 20 are not shown herein, but may comprise the usual reducing gear train connected to an electric motor as a prime mover. Conventional clutch means are not shown, but may be utilized for connecting and disconnecting the shaft 20 as desired when it is desired to have a continuously operating motor.

The'cutting die 13 is arranged to work against a rotatable platen 21, which platen provides a support means for the web as it passes thereover. It will be appreciated that the web 10 is caused to be pulled in the direction of the arrow indicated in FIG. 2 by the action of the cutting edges of 'the die 13 working against the platen 21. As shown in FIG. 3, the trailing marginal edge 16 is just about to leave the Web 10, but has not yet done so.

The shaft 20 terminates in a radial disk cam 22 having an operating cam profile comprising surfaces 23, 24, 25 and 26, of which surface 26 is of circular circumference. These surfaces are engageable with a cam roller 27 for operation of a web-clamping means, which will hereinafter be described. The shaft 20, the die 13 and the cam 22 are preferably locked together to move as a unit, but the cam 22'is arranged to be rotatably adjustable relative to the shaft 20 by conventional fastening means not specifically illustrated.

As indicated in FIGS. 1, 2 and 3, the cam follower or roller 27 is arranged to ride upon the cam surface of the cam '22 and is supported at one end of a cam link 28. The link 28 is pivotally supported at its opposite end by means of a pivot pin 29 attached to and extending laterally from an upright arm 30 of a generally U-shaped, pivotally mounted, rocker bracket, indicated generally by the reference numeral 31. The supporting rocker bracket 31' is suspended from a supporting quill shaft 32 by means of the spaced, upstanding ears 30 and 33. The quill shaft 32 is journalled for rotational support about stationary pins 34 extending laterally towards one another (not shown) and supported by means of the spaced housing walls 35 and 36 (see FIG. 4).

The base of the rocker bracket 31 includes a web support or guide member 40, and it will be noted from the views of FIGS. 2 and 3 that the web 10 normally rests thereon. Guide member 40 is preferably provided with down-turned, opposed edges to permit ease in threading and to prevent damage to the web material as it is advanced thereover. The rocker bracket 31 further includes a rotatable shaft 41 journalled at its ends in the ears or upright members 30 and 33. The shaft 41 also supports a laterally extending web clamping member 42 having an upwardly bent outer end and which is movable with the shaft 41 and arranged to engage the upper surface 'of' the web 10, as hereinafter will be described. The shaft 41 further supports an upwardly extending arm 43 and a spring'support member 44, both of which are fastened to the shaft to move with it as a unit. A coil spring'45 is fastened at one end to the spring support 44 and at the other end to the upright 30 of the rocker bracket 31. Spring 45 provides a means of normally urging the shaft 41 and its associated elements 42, 43 and 44 in a counterclockwise direction, as viewed in FIGS. 2 and 3. The arm 43 acts as a stop member and is arranged for rotative "adjustment by means of engagement with an adjusting screw 46, which screw is threadingly supported by means of a laterally extending support member .47 which, in turn, is fastened to the wall 36 as shownin FIG. 4. A 'locknut 48 is provided for maintainingthe screw 46 in the desired adjusting position. The function of the various components just described will be laterdiscussed.

Journalled upon the shaft 41 is a concentric, rotatable sleeve 'member 50, having secured thereto a second web clamping member 51 extending oppositely of the clamping member 42. The sleeve 50 further includes a laterally extending spring support arm 52 arranged to support a spring 53 at one end thereof. The opposite end of the spring 53 is supported by the upright 33 of the rocker bracket 31. The sleeve 50 and the clamping member 51 and the'spring support arm 52 are adapted for joint rotative movement with one another. It is to be further noted that it is preferred to provide a relatively light spring 53 as compared to the relatively heavy spring 45. The arm 52 is preferably provided with an angularly extending portion 54 for purposes of manually releasing the clamping member 5 1 from the web when it is so desired.

Returning again to the link member 2 8, which supports the cam roller 27, it will be noted that this link is further supported intermediate its ends by means of a pivot pin 60 and a supporting link 61. The opposite end of the supporting link 61 is eccentrically supported by means of a pivot member 62 extending from the head of a rotatably adjustable bolt 63, and which pin is disposed eccentrically of the axis of the bolt 63. The bolt 63 is preferably seated in an aperture of the wall 36 and is retained in place by means of conventional nut 64 (see FIG. 5). A set screw 65 is utilized to hold the bolt 63 in adjusted position, such adjustment being made for purposes hereinafter discussed. It is to be noted, for present purposes, however, that the adjustable link 61 and its supporting elements may be positioned below the link 28 and operate with equal effectiveness.

To complete the unit, a hinged cover 66 may be provided as shown in FIGS. 2 and 3, and if so desired, the cover may be made of a transparent plastic material for purposes of observing the correct operation of the various components when so desired.

The present embodiment provides a constant frictional drag on the Web 10 to prevent the web from wandering or creeping which may occur due to a variety of reasons. The drag is accomplished by means of the clamping member 51, exerting constant and uniform pressure on the web 10, Which is supported by the base 40 of the bracket 31. Thus, when the die 13 acts to pull the web forward (at a time when the web is not clamped by the member '42), the die Works against the friction of the surfaces of the members 40 and 51. The tension of the spring 53 is such that stabilization of the movement of the web is achieved without affecting its uniform movement when the die 13 is pulling it forward.

The present embodiment also provides an intermittent clamping action on the web by means of the member 42,

which member presses the web downward against the base 40 of the bracket 41. The clamping member 42 is pressed against the web by means of the spring 45 with the arm 43 encountering the adjusting screw 46. The purpose of the screw is to adjust the gap between the clamping surface provided by the members 40 and '42, and to open and close the clamping surfaces by providing a stop for the arm '43 in its rearward travel; This adjustment is necessary to provide an opening which will be sufficient to accommodate the range of web thicknesses which are being used.

The present arrangement permits the web in its forward advancement, to tend to pull the clamping surfaces together after they have gripped it. In like manner, when the clamping device operates to pull the web 10 in a reverse direction, the clamping members tend to tighten against the web as it resists movement. The surface between the member 51 and the base 40 of the bracket 31 provides a constant pressure means, exerting the uniform pressure in the web 10 at all times in preventing it from wandering or creeping during a period when it is not'being clamped by the clamping member 42. The web contacting surfaces of the clamping members '40 and 51 rock back and forth with the bracket 31 of the equal spacing device, and therefore the device is never caused to work against the friction of these surfaces.

In the operation of the above-described equal spacing mechanism, after the web 10 has been threaded between the upper clamping members 42 and 51 and the base 40 of the bracket 31, manually fed between the shaft 29 and platen 21, the device may be started into rotative operation withthe die 13 rotating in the direction of the arrow of FIGS. 2 and 3. The leading edge 15 of the die will begin to cut through the upper laminate 11, and continue with the side cutting margins of the die 13, and in so doing, will tend to pull the web in a forward direction until the trailing edge 16 of the die '13 is just about to leave the web as shown in FIG. 3. In this position, it will be observed that the cam follower 27 has become free to move forwardly. Until this time, the cam follower 27 has been urged against the cam 22 by means of the action of the spring 45 as reflected in the rocker bracket 31 when the arm 43 engages the stop screw 46. Now that the cam follower 27 has become free to move forwardly, just before the trailing edge 16 of the die 13 leaves the web 10, the forward movement will cause the rocker bracket 31 to move forward and thereby permit the arm '43 to leave the adjustment screw 46 and cause the spring 45 to clamp the clamping member 42 against the web 10. The rocker bracket 31 will continue its forward movement along with the web 10 until the trailing edge 16 of the die 13 leaves the web and the web ceases to move.

As the shaft 20 continues to revolve, the cam surface 25 will next come into contact with the cam follower 27 to cause the mechanism comprising the components of the rocker bracket 31, to be forced rearwardly and thereby to pull the Web 10 rearwardly along with it by engagement of the clamping member 42 with the web surface. When the leading edge of the die 13 next comes into contact with the web '10, it will do so at a point on the web spaced a specific distance from the cut previously made by the trailing edge 16.

Regardless of variations in the point at which the trailing edge of the die 13 releases the web 10, the present device will take such variations into account and compensate for them, to thereby provide equal spacing results. Such uniform spacing can be achieved that the leading edge of the die 13 can be made to pick up the web 16 each time precisely where the trailing edge 16 left ofi, so that there will be neither any space between the labels 17, nor an overlapping of these labels. This is an important advantage, as it reduces waste material between labels and also simplifies removal of waste along the two sides when it is later desired to do so.

It will be apparent that the eccentric adjustment for the link 28, comprising the elements 6065, will permit variations to be made in the spacing between the labels 17. As stated previously, the eccentric arrangement can be placed on the opposite side of the link to provide desired adjustments. However, when positioned upwardly of the link 28, as shown in FIGS. 1, 2, 3 and 4, it provides a convenient, accessible means for engaging the head of the bolt 63 with a wrench, and to even permit the necessary adjustments to be made while the machine is in operation. It is therefore not necessary to stop the machine between adjustments.

The embodiment of FIG. 8 will next be described, it being understood that like parts of each embodiment are designated by like reference characters.

As shown in 'FIG. 8, the web 10 has been advanced in the direction indicated by the arrow, by the action of the cutting die 13 working against the platen 21. The trailing edge 16 of the die 13 is nearly ready to leave the web 11 but has not yet done so. The present embodiment utilizes no rolling cam follower, but provides a fol lower link 70 having a free end portion 71 adapted to act as a cam follower. The link is supported intermediate its ends by means of a link member 72 pivotally mounted on a pin 73 laterally extending inwardly from and secured to the wall 36. The links 70 and 72 are pivotally joined with one another by means of another pin 74. In this case, adjustments are made entirely by means of rotating the cam 22 relative to the shaft 20 upon release of the set screw 75 which is fiictionally engageable with the shaft 20.

The follower link 70 is biased towards the cam 22 by means of a tension spring 75a, engageable at one end with an aperture in the upright 76 of the rocker bracket, indicated generally by the reference numeral 77, and at its opposite end with the top of a lever arm 78. The follower link 70 is pivotally attached to the lever arm 78 by means of the pivot pin 79, and the lever arm 78, in turn, is pivotally mounted relative to the upright 76 by means of a pivot support pin 80. A laterally extending portion of the lever arm 78 includes a clamping nib 81, arranged to clampingly engage the web 10 at one side thereof. The web 10 normally rests upon the supporting base 82 of the rocker bracket 77.

The rocker bracket 77 is generally U-shaped and is pivotally suspended by spaced uprights (one being omitted herein) from a quill shaft 32 rotatably supported concentrically of inwardly extending stationary pins 34, as in the previously described embodiment. The rocker bracket 77 is free to swing on the shaft 34, but is stopped from movement beyond a predetermined clockwise direction by means of a laterally extending stop pin 83.

It will thus be apparent that the follower link 70, which is biased against the cam .22 by means of the spring a, the end-supporting lever arm 78, and the inter-action of the stop pin 83, as shown in FIG. 8, with the nib 81 being in clamping contact with the web 10. Just before the trailing edge of the edge 16 of the die 13 leaves the web 10, the follower link 70 will be free to move in response to the spring 75a. The follower link 70 will be free to move in response to the spring 75a, and will therefore clamp the web 10 through the nib 81, and will then continue to move forward with the web until the trailing edge 16 of the die 13 leaves the web at some time prior to the point where the end portion 71 would come into contact with the cam surface 24. As the link 70 moves forwardly, the nib 81 of the lever 78 is caused to clamp tightly against the web 10 and against the base 82 of the rocker bracket 77. The rocker bracket 77 will now be caused to move forwardly with the web 10 until the trailing edge 16 of the die 13 frees itself from the web 10 and the web 10 ceases to move. It will be observed that the shaft 20, the die 13 and the cam 22 are locked for movement together after initial rotative adjustment of the cam 22 is made with respect to the shaft 20.

As the shaft 20 continues to rotate, the cam surface 25 of cam 22 will next come into contact with the follower link 79 and the web-gripping mechanism will thereby be forced rearwardly and cause the web 10 to be pulled with it. When the leading edge of the die 13 next comes into contact with the web 10, it will do so at a point on the web 10 spaced a specific distance from the cut made by the trailing edge 16 of the die 13. The space between the labels 17 die cut by the present embodiment may be adjusted by simply rotating the cam 22 in one direction or the other with respect to the shaft 20, and locking it in the new position by means of the set screw 75. This space may be varied at will, from a no-space, an overlapping condition, or to a medium, but uniform, amount of space that would be approximated, but which would not necessarily be uniform if there were no spacing device present.

It will be apparent that the embodiment of FIG. 8 provides a device including the basic concepts of the present invention, but that the earlier described embodiment of FIGS. 1-5 provides a more conveniently operated device where frequent adjustments in spacing are to be made. It will be apparent that if frequent adjustments are to be made, it is relatively inconvenient to make such adjustments by rotating the cam 22 with respect to the shaft 20 and locking it in a new position each time. Therefore, the prefenable arrangement, as found in the first described embodiment, provides an eccentric support for the intermediately disposed supporting link for the cam fol-lower. That is, horizontal mot-ion of this pivot point will not change the position of the cam follower, but vertical motion has the same effect as rotating the cam 22 relative to the shaft 20. In the first described embodiment the pivot support was further disposed upwardly of the cam follower to provide further ease in making the adjustments. The adjustments can be made while the device is in operation, and brought quickly to the desired spacing.

In the foregoing description, it will be apparent that the present invention has provided a simple and easily operated device for insuring equal spacing between portions die cut and/or printed on a continuous web, and further provides facilities for making immediate changes in the said spacing.

I claim:

1. In a device including rotationally supported means for making periodic impressions upon a continuous web of material and wherein said means is furtherarranged to advance said web in a forward direction concurrently as each impression is made thereon; the combination therewith of equal spacing means comprising web support means, a web clamping member spaced rearwardly of said rotationally supported means relative to the direction of advancement of said Web and being biased towards clamping engagement with said web when the web is supported by said web support means, and adjustable reciprocating motion translating means arranged for operative engagement with said rotationally supported means and with said web clamping member, said motion translating means being arranged to resist the normal bias of said web clamping member to prevent engagement thereof with said web during its forward advancement, and alternatively, being further arranged to permit said clamping engagement adjustably relative to the release position of said rotationally supported means and said web.

2. In a device including rotationally supported means for making periodic impressions upon a continuous web of material and wherein said means is further arranged to advance said web in a forward direction concurrently as each impression is made thereon; the combination therewith of equal spacing means comprising a pivotally supported rocker bracket spaced rearwardly from said rotationally supported means relative to the direction of advancement of said web and having a web supporting base, a web clamping member pivotally supported by said rocker bracket and biased towards clamping engagement with said web, when the web is supported by said base, and adjustable reciprocating motion translating means arranged for operative engagement with said rotationally supported means and with said rocker bracket, said motion translating means being arranged to resist the normal bias of said web clamping member to prevent engagement thereof with said web during its forward advancement, and alternatively, being further arranged to permit said clamping engagement adjustably relative to the release position of said rotationally supported means and said web.

3. In a device including rotationally supported means for making periodic impressions upon a continuous Web of material and wherein said means is further arranged to advance said web in a forward direction concurrently as each impression is made thereon; the combination therewith of equal spacing means comprising a pivotally supported rockerbracket spaced rearwardly from said rotationally supported means relative to the direction of advancement of said web and having a web supporting base, a web clamping member pivotally supported by said rocker bracket and biased towards clamping engagement'with said web, when the Web is supported by said base, and adjustable reciprocating motion translating means comprising a radial disk cam member arranged for rotative concurrent movement with said rotationally supported means and including a cam profile having a circular cam surface and a generally concave surface portion,'and a cam follower engageable with saidcam profile and operativ'ely associated with said web clamping member and arranged to resist the normal bias of said 'web clamping member when in engagement with said circular cam portion to prevent engagement of said clamping member with said web during its forward ad vancement, and alternatively, to permit said normally 8 biased clamping engagement when in engagement with said concave cam pontion.

4. The equal spacing means of claim 3, wherein the said radial disk cam member is disposed in coaxial relationship with the said rotationally supported means and rotatably adjustable relative thereto.

5. The equal spacing means of claim 3, wherein said cam follower is supponted intermediate its ends by means of an adjustable supporting element.

6. In a device including rotationally supported means for making periodic impressions upon a continuous web of material and wherein said means is further arranged to advance said web in a forward direction concurrently as each impression is made thereon; the combination therewith of equal spacing means comprising web support means spaced rearwardly from said rotationally supported means relative to the direction of advancement of said web, a first web clamping member biased towards clamping engagement with said web when the web is supported by said web support means, adjustable reciprocating motion translating means arranged for operative engagement with said rotationally supported means and with said web support means, said motion translating means being arranged to resist the normal bias of said first Web clamping member to prevent engagement thereof with said web during its forward advancement, and alternatively, being further arranged to permit said clamping engagement adjustably relative to the release position of said rotationally supported means and said 'web, and a second web clamping member arranged to exert a relatively light and continuous pressure against said web and including cyclic periods of disengagement of said first web clamping member from said web.

7. In a device including rotation-ally supported means for making periodic impressions upon a continuous web of material and wherein said means is further arranged to advance said web in a forward direction concurrently as each impression is made thereon; the combination therewith of equal spacing means comprising a pivotally supported rocker bracket spaced rearwardly of said rotationally supported means relative to the direction of advancement of said web and including a Web support base, a web clamping member pivotally supported by said rocker bracket and biased towards clamping engagement with said Web when the Web is supported by said web support means, adjustable reciprocating motion translating means comprising a radial disk cam member disposed in coaxial relationship with said rotationally supported means and including a cam profile having a circular cam surface and a generally concave surface portion, a cam follower including a link pivotally connected to said Web clamping member, a supporting lever disposed intermediate the ends of said link and arranged for pivotal connection therewith, and a stop element spaced from said rocker bracket to prevent its pivotal movement beyond a selected position rearwardly relative to said advancing web to permit the clamping engagement of said web clamping member and said web at a clamping position relative to the release position of said rotationally supported means and said Web.

8. The equal spacing device of claim 7 wherein the said supporting lever includes an adjustable disposed fulcrum support oppositely spaced from the pivotal connection with said link.

9. The equal spacing device of claim 6, wherein a second clamping member is pivotally supported by said rocker bracket and arranged to exert a relatively light and continuous pressure against said web and including periods of disengagement of the said first mentioned clamping member from said web.

References Cited in the file of this patent UNITED STATES PATENTS

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