US 2939505 A
Description (OCR text may contain errors)
June 7, 1960 c. H. BUCHER ErAL FEEDING AND CRIMPING METHOD AND APPARATUS Filed April 23, 1956 6 Sheets-Sheet l las INVENTORS.
June 7 1960 c. H. BucHl-:R ET AL 2,939,505
FEDDING AND CRIMPING METHOD AND APPARATUS Filed April 23, 1956 6 Sheets-Sheet 2 INVENTORS, Cnr( H. Bucher, Dame\ J. Cmmeq and .nr E. Folkenrotk June 7,1960 c. H. BucHER x-:TAL 2,939,505
FEEDING AND CRIMPING METHOD AND APPARATUS Filed April 23. 1956 6 Sheets-Sheet 3 57 INVENTORS,
Carl H, Bucho; Dan\e\ d. CromIeq BY and QOH Fdktnroih 6M/a, Www/W June 7, 1960 c. H. BUCHER ETAL 2,939,505
FDEDING AND CRIMPING METHOD AND APPARATUS 6 Sheets-Sheet 4 Filed April 25, 1956 l d m mh 0I t mam .hle mmmm/ m f H m dl mmm H CaE D l m. u V. B
June 7, 1960 c. H. BucHER ETAL 2,939,505
FEDDING AND CRIMPING METHOD AND APPARATUS Filed April 25, 1956 6 Sheets-Sheet 5 INVENTORS, CoH H. ucher, Damd K). Cmwleq June 7, 1960 c. H. BucHER ETAI. A D 2,939,505
' FEEDING AND CRIMPING METHOD AND APPARATUS Filed April 2s, 195e 6 Sheets-Sheet 6 V50 INVENTORS CGH H. Bucher Daniel Cmwew amdQml Folkenroth h/ film', f
United States Patent O FEEDING AND CRIMPIN G METHOD AND APPARATUS Carl H. Bucher, Harrisburg, Daniel il. Crowley, Steelton, and Earl E. Folkenroth, Lenker Manor, Pa., assiguors to AMP Incorporated, Harrisburg, Pa.
Filed Apr. 23, 1956, Ser. No. 579,937
3 Claims. (Cl. 153-1) This invention relates to methods and apparatus for feeding and for crimping, particularly `methods and apparatus for Ifeeding and crimping `electrical terminals onto wires and the like.
An object of the invention is to `feed elongated 'loose piece articles to a crimping .die set or the -like and to .crimp the articles onto the end of a wire or the like.
A further object is to provide a method and apparatus for feeding elongated loose piece articles to a crimping die set and to position the articles at the proper location in the die set for the crimping operation.
A further .object is to provide a single apparatus embodying both crimping means and means operable in timed relation with operation of the crimping Imeans for placing an -electrical terminal or the like in the crimping means.
A further object is to provide a .method and apparatus lfor simultaneously feeding two elongated loose piece articles from a single source of such articles.
Other .objects ,and attainments of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in .conjunction with the drawings in which 4there is shown and described an illustrative .embodiment of the invention; it is to be understood, however, that this embodiment is ,not intended to be exhaustive nor limiting of the invention but is given for purposes of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of yapplying it in practical use `so ,that they may modify v,it in various forms, each as may be best suited .to the conditions of a particular use.
In ,the drawings:
Figure 1 is a frontal view of a preferred embodiment of the invention;
Figure 2 is a view taken along the lines ure l;
Figure 3 is a view Ytaken along the lines ,Illlll of Figure 1;
Figures 4, 5, 6 Aand 7 are :fragmentary views of the terminal ejector components ofthe apparatus and ,showing the various stages in the feeding and positioning of a terminal;
Figure 8 is a perspective :fragmentary view with parts broken away of the crimping die ,set Aof the preferred embodiment of the apparatus;
yFigure 9 is a frontal View, vwith :parts :broken away, of the die set of Figure 8;
Figure '9A is a plan view of a punch which forms part of the die yset of Figure 9;
Figure 10 is a perspective view fof 4a plug-type .termination produced by the operation of the embodiment of Figures '-l-9;
Figure 11 is a perspective view of `a vibratory-.type feeding .device andan associated .feed track by `means tof which terminais are fed to .the ejector of Figures 47:;
n n of Fign 2,939,505 Patented June 7, 1960 Figure 12 is a sectional View of a portion of the structure shown in Figure 1l;
'Figure i3 is a sectional view taken along the lines XIII-XIII of Figure 14 of the feed track showing the movements of terminals therethrough; and
Figure 14 is a top plan view, with parts broken away, of the -feed track of Figure 13.
Referring now to Figures 1, 2 and 3, the reference numerals 2, 2 denote a pair of C-shaped frame members `disposed in side by side relationship and connected together by means of a cross member 3. The frame members are supported on supports 4, d' and are secured thereto by means of bolts 6, 6. The lower portions of the frame members provide flanges 8, 8' which support a single base plate 10 which is preferably secured to the flanges as by bolting. The base plate 10 in turn supports a crimping die assembly generally indicated by the reference numeral 11 which is described in detail below. A main shaft 12 is journalled within the C-shaped frame members in the upper portions thereof and has secured thereto at one end a main shaft flywheel 14 which is connected by means of a belt 16 to a pulley 13 on the end of the shaft 19 of an electric motor 2t). An eccentric 22 is keyed or otherwise secured to main shaft 12 at a location between yframe member 2, 2 and accommodates the bearing portion 24 of a connecting rod 26 which in the disclosed embodiment is shown as being of adjustable length. The connecting rod is connected by means of a ball and socket joint 28 to a slide member 30 which recip-rocates in guideways 32 on frame members 2, 2. A cam holder 34 is secured to the lower end of slide 30 yby means of a fastener 31 and in turn has secured thereto a U-shaped cam 3 6 vhaving cam surfaces 38, 38 which are adapted to close a crimping die set mounted within assembly 11 as described below.
From what has `b een said thus far it will be apparent that as the shaft rotates, the connecting rod, slide, and cam are reciprocated towards and away from base plate 10. The apparatus disclosed is adapted for intermittent rather than continuous operation and it is therefore necessary to provide a clutch mechanism 13 on the power shaft so that the operator can engage the clutch at the l.appropriate time to cause the shaft -12 to rotate through a single revolution thereby to effect a single crimp. This clutch mechanism and the actuating means therefor are not disclosed in detail inasmuch as such devices are commonly known to the art. The clutch mechanism is actuated by a bell crank lever 15a connected to a link 15 which is connected to a solenoid 17 which in ,turn is energized by a foot `switch (notshown). With this arrangement, energization of the ,solenoid engages the Vclutch to rotate the shaft through a single revolution.
Referring now to Figures 8, v9 and 9A, crimping die assembly 11 comprises a single guide block 40 of substantially channel shaped cross section which faces the front of the machine as viewed in Figure l. Centrally mounted Within this guide block vis a stationary camming block 42 which is lsecured to the guide vblock by means of suitable fasteners 44. Openings 43, 4.3 are provided on the back surface of the guide block on each side of the stationary camming block 42. Within the guide block and on each side of the stationary cannning block 42 there is provided crimping die set. Since both the right hand and the left hand die set are alike, a description of one will suflice for both. Accordingly only the right hand die set as viewed in Figure 1 will be described here. In the drawing, primed reference numerals are employed to differentiate between the right hand die set Vand the left vhand die set.
Stationary ,camming block .42 provides sloping l.Cammina lsurfaces l4.6, which lface yrightwardly as viewed iin lFigures 8 and 9. A movable camming block 48 is positioned in guide block 40 near the end thereof and is adapted for slidable movement towards and away Ifrom xed camming block 42. This movable camming block provides camming surfaces 50 which face camming surfaces 46. A bifurcated extension S2 on the end of movable camming block 48 accommodates a pin 54 having a cam follower 56 mounted thereon which is adapted to be contacted by camming surface 38 as shown best in Figure 1. Pin 54 additionally has secured thereto one end of a coiled spring 55 which is secured at its opposite end to a bracket 57 which in turn is fastened to base plate 10. This spring is adapted to retain movable camming block 4S in the position of Figure l although the camming block can be moved inwardly against the force of this spring.
The reference numerals 58 denote a pair of mating die blocks having opposed surfaces 60 providing hemicylindrical grooves 62 therein, these grooves being so shaped as to `form a terminal receiving cavity when the die blocks are closed and surround and grip a terminal. It will be obvious that the shape of grooves 62 will vary in any specific embodiment of the invention depending upon the precise type of terminal which is being applied to wire ends. The frontal surfaces of the die blocks 58 are hyperboidal in order to constitute a guiding surface for a wire and these surfaces fair evenly towards the grooves 62 `at their inner ends and merge with aprons 72 at their extremities. It will be noted that the left hand die block provides an apron adapted to cover a portion of the stationary camming block 42 while the right` hand die block 58 provides an apron adapted to extend over the bifurcated extension 52 of the right hand camming block.
Each of the die blocks 58 provides a plurality of passages 66 which radiate from the grooves 62 and which accommodate punches 68 having indenting portions 81, 83. Passages 66 are enlarged at their ends for the accommodation of springs 70 which are positioned in slots 69 in the punches. When the parts are in their normal -position of Figure `9, the ends of the punches project beyond the rear surfaces 74 of the die blocks but can be urged to a position iiush with these rear surfaces and into 'the grooves 62 with concomitant compression of springs 70. It should also be noted at this point that these rear surfaces '74 of the die blocks are preferably complementary to the camming surfaces 46, 50 of the camming blocks. The die blocks thus nest between the two camming blocks 42, 4S and normally are spaced therefrom by virtue of the action of springs 70 and punches 68.
The die blocks 58 are loosely connected to their respective stationary and movable camming blocks by means of keys 78 and keyways 80. The Ikeys are integral with the die block aprons 72 and extend into oversized keyways 80 of the camming blocks so that the parts are retained in assembled relationship and limited movement of the die blocks is permitted relative to the camming blocks. A front cover 79 is secured to block 40 to retain the parts within the guide block and provides a pair of openings 79a, 79a to permit insertion of a wire end.
In the operation of the crimping die assembly, as cam 36 descends, cam surface 38 urges movable camming block 48 inwardly toward fixed camming block 42. Such movement of the movable camming block will first move the die blocks against each other; that is, will move surfaces 60 of the die blocks i-nto mating relationship. When the die blocks are thus positioned, further inward movement of movable camming block 48 drives the punches relatively through their passages against the force of springs 70 and into the cavitydeiined by the grooves 62 where they indent a terminal upon itself thereby to crimp it onto a wire. It will be apparent from the drawing that after closure of die blocks 58, the two die blocks are moved as a unit towards stationary camming block 42 andrit is this motion which drives the punches relatively 4 to the die blocks into indenting relationship with the terminal. The foregoing description relates only to the right hand crimping die set. The left hand crimping die set is similarly actuated by descent of cam 36 and the effect of camming surface 38'.
An advantageous lfeature of the die block and punch structure shown in the drawings is that the several punches of each die block move at the same speed and move the same distance during the descent `of cam 36. This result is achieved by virtue of the `fact that the angles of intersection between the path of travel of punches 68 and the camming surfaces 46, 50 are equal. This is shown in Figure 9 on the two upper punches of the left hand one of the die blocks. It will be noted that the each of these punches intersects the camming surface at an angle a. Since all of the punches intersect their respective camming surfaces at this same angle all of the eight punches are driven the same distance into a terminal during a crimping operation. Y
The apparatus of Figure 1 is adapted to produce crimped connections of the type shown in Figure '10 to comprise a generally cylindrical plug portion 86 which is separated by a circumferential collar 90 from a crimping portion 88. Preferably the wire is provided with a tubular sleeve on the end thereof (not specifically shown) onto which the terminal is crimped by means of the indentations 82, 84. It is realized, of course, that the invention is applicable to other types of tubular connectors and that alternative types of crimps can be made by changes in the construction of the punches 68.
A pair of side by side terminal feeding and positioning mechanisms are provided to -feed and position a terminal to each of the crimping die sets Within the die assembly. Since these feeding and positioning mechanisms are substantially alike a description of one will suiiice for both, Accordingly only the right hand feeding and positioning means is specifically described in following paragraphs.
The uncrirnped terminals are delivered by a tube 98 into an ejector block generally indicated at 92 which provides in its upper portion a chamber 94. The ejector block, as shown best in Figure 3, is positioned directly behind the crimping die set in alignment with opening 43 and is secured to a support plate 93 which is secured to and extends rearwardly from plate 10. A pair of aligned passages 100, 102 extend through block 92 and communicate with chamber 94. These passages permit reciprocation of a ram or plunger 104 therethrough so that a terminal can be pushed through passage 102 to a position between the crimping dies for the crimping operation. The chamber 94 is of a length L slightly in excess of the length of the terminal being fed and of a height H slightly less than the length of the terminal being fed. The depth of the chamber (as measured normally of the plane of the paper in Figure 4), is slightly in excess of the thickness or diameter of the terminal but not lso much in excess as to permit undue wobbling of the terminal or cooking thereof as it falls and is positioned as will be explained below. A confined passageway for the terminals in the form of a exible tube 98 enters the chamber along the side thereof opposed to the side through which plunger 104 reciprocates. This flexible tube is secured at its end to a mounting block 96, which provides an aperture for receiving the end of the tube 98. This mounting block is, in turn, adjustably secured to ejector block 92.
The tube 98 is charged with a succession of terminals by any suitable means such as by the vibratory feeding device described below. The terminals are aligned with their open ends entering chamber 94 so that they are delivered by gravity feed into the chamber as shown by terminal T in Figure 4.. A previously positioned 'terminal T' Will be positioned in the chamber against one of the edges 99 thereof. As the plunger 104 moves lthrough the chamber, terminal T is moved from the position of Figure 4 to the position of Figure 5 and simultaneously ,terminal T is toppled so that it rests .upon plunger 104 at the end of the forward motion of the plunger. Thereafter terminal T is moved .up to the desired position between the die blocks by further forward motion fof the plunger.V .On withdrawal'of the plunger terminal T drops into the position ,against vedge v99 formerly occupied by T while the next succeeding one of the terminals drops against .the forward (tapered) end of terminal T.
In order to prevent a possible cockingvor jamming of terminals within chamber V92 Iprefer to provide a biasing means in the form of a small weight indicated by reference numeral 106 in the form of a rod extending through the chamber and having a weighted washer 108 on the end thereof. This rod extends through an elongated slot 110 so that a slight Vertical movement thereof is permitted. As will .be .apparent from .the drawing then, the rod can be displaced upwardly by terminal T during the forward stroke .ofthe ram while on the backward stroke of the ram the weight of this rod will be effective to push the terminal .downwardly against the oor of the chamber.
It can thus be seen from Figures 4-7 that in the operation of the feeding means of the invention, the terminals are delivered in an axial succession downwardly into the chamber and the leading one of the terminals is toppled by reciprocationof the plunger as it travels through the chamber to move or position a previously toppled terminal up to the crimping dies. After the toppling action takes place, the toppled terminal assumes a position which the previously toppled terminal had occupied in that it reposes beneath the succession of terminals with the leading one of the succession having its end resting upon the toppled terminal.
VIt was pointed out above that chamber 94 is of a length L .slightly in excess of the length -of the terminals, of a height H slightly less than the length of the terminals and a `depth slightly in excess of the diameter of the terminals. The importance of the relative size of chamber 94 and the dimensions of the terminals will be apparent from a consideration of the foregoing explanation of the operation. The depth of chamber 94 must be sufficient to accommodate the diameter of the terminals .but must not be so great as to permit jamming. Also the depth of the chamber must be such that the entering terminal (terminal T Figure 4) will rest upon the previously toppled the length L of the `chamber must beV greater than the length of the terminal but it must not be excessively greater since terminal T must be positioned beneath terminal T during the portion of the stroke shown in Figures 5 and .6.
Referring now .to Figure 3 which shows the plunger actuating mechanism, plungers 104, 104 are each secured to a yoke 103 which in turn is secured to the end of a piston rod 105 .of a piston in a cylinder 107. Pistoncylinder 107 is of the double acting type and is supplied with compressed air or other fluid by means of a hose 109 and a three-Way solenoid valve 111 which is energized by a pair of microswitches, one of which, 112 is located on a bracket 114 secured to the cylinder itself. This microswitch provides a contact portion 116 which is adapted to be .contacted by yoke 103 on the return stroke of the piston rod, (i.e. as the piston rod travels backwardly from the position of Figure 7). Upon such actuation of microswitch 112 air is admitted through valve 111 tothe rear end of vcylinder 107 to drive the piston and piston rod forwardly thereby to feed and position a terminal in each of the crimping die sets. A second microswitch 118 is secured to frame member 2 and Ais adapted to be closed -by a cam on lshaft '12. Upon closure of this switch, airis admitted through valve 111 to the front end of cylinder 107 to4 return piston rod 105 to the position of Figure 3.
Conductors Vin cable 111a connect valve 111 to the microswitches. Details of the electrical system other than the location of the microswitches and the solenoid valve are omitted Vin the interest of Vsimplicity since such double acting cylinders having solenoid valve and microswitch controls are commonly known to the art.
Normally when .the parts are at rest with the press structure at top dead center position, the piston rod and plungers 104 are in their forward position of Figure 6. When the operator initiates the crimping operation by engaging clutch 13, the plungers remain in the position of Figure 6 during the closure of die blocks 53 as cam 36 descends. During the Vlatter portion of the downward stroke of cam 36 .and after die blocks 58 have closed on the terminal, switch 11S is tripped by cam 120 to cause the plungers to be withdrawn. When the piston rod reaches its rearward position of Figure 3, switch 112 is closed by yoke 103 to admit air to the opposite end of the cylinder to return the plunger to the position of Figure 6.
Referring now to Figures ll, l2, 13 and 14, the disclosed vembodiment provides also automatic feed means for feeding terminals to the tubes 98, 98. This feed means comprises a vibratory-type feeder 122 which is mounted over frame members 2, 2 by means of brackets 125 and a support plate 127.V This feeder comprises a vibrator 124 and a container 126 providing a helical terminal track i128 on its internal surface. Vibratory feeding devices of this type are `commonly known to the art, Vare-ccrmme-rcially available .and need not be described further. Y
A feed track 130 is mounted on container 126 at the end of helical feed track 128. The feed track comprises a pair of side by side rails 132 which yare secured in spaced relationship by pins 134, 133. The rails are spaced apart a distance slightly .greater than the diameter vof the terminals but slightly less than .the diameter of the* collars of the terminals so that as the terminals are fed onto the track `130 the pointed end of each terminal drops between the -rails with collar 90 of each terminall preventing the terminal from dropping between the rails. VIft should be noted that the terminals will assume the position shown in Figures l13 and 14 whetherV they enter feed track 130 open end first or tapered end first. When 'a terminal .enters track 130 open end first, the tapered end of the terminal will drop between the rails as soon `as it clears `pin 134, when a terminal enters track 130 tapered end first, the .tapered end will immediately drop between therails.
VRails 132 curve downwardly as indicated at 133 and a tripping means in the form of a pin 136V is provided which connects the rails at a point near this curve. This pin is so located that the tapered endof each terminal will b e'tripped as the terminals travel from left to right as viewed in Figure 13) under the influence of the vibrator. This txipping of the terminals causes them to fall open end first onto a plate 140 where they are guided into feed tubes 98, 98 as described below.
Extensions 130a of the rails extend outwardly beyond the curve and accommodate pin 133 which maintains the rails in their spaced relationship. Also, if the tapered end of a terminal should fail to drop between the rails as shown in Figure 13 by reason of its being imperfectly formed `or for any other reason, it would be conveyed to the end of extensions '130:1 and drop onto a plate 140 as described below.
Disposed beneath Itrack 130 is an inclined plate 140 having a pair of grooves 142, 142 which diverge from a point approximately A.beneath the end of track 130 which grooves lead to inlets 146, 146' which in turn enter tubes 98, 98. Thus as the terminals drop from track 130 they 7 ordinarily fall into one of the grooves 142,142' and-enter one of the tubes 98, 98'-, the rate of terminal feed froml the feeding device 122 being such that lan adequateA number of terminals are supplied to each of the tubes. In actuality it will frequently be found that an excess of terminals will be fed to track 130. In order to recover the excess, catch troughs 154 are provided on each-'side of track 130 and sides 152 are provided on plateV 140. Grooves 144 provided along the sides of plate '140`convey excess terminals which overflow to a chute 150 which lead to a container 148.
From the foregoing description, it will be apparent that the invention operates as follows: The feed tubes 98, 98 are maintained filled each with a succession of terminals by the feeding device as described in immediately above paragraphs. When the machine is at rest the cam 36 is at its top dead center position or slightly past its top dead center position and plungers 104 are in their forward position as shown in Figures 3 and 6. The operator inserts each end of a wire into the space between the die blocks and into the open ends of the previously positioned terminals. Thereafter the operator trips the foot switch to engage clutch 1-3 and rotate shaft 12 through a single revolution. This causes cam 36 to descend and close the crimping die setsto produce a termination of the type shown in Figure 10 on each end of the wire. During the latter portion of the downward stroke of cam 36, and after die blocks 58, 58 have been closed to grip the terminals, microswitch 118 is tripped to cause withdrawal of plungers 104. A forward stroke ensues when microswitch 112 is tripped by yoke l103. Also during the final portion of the downward stroke of cam 36, punches 68 are driven into crimping relationship with the terminals to produce crimped connections of the type shown inY Figure 10. As cam 36 moves upwardly after the crimping operation, plungers 104, 104' complete their forward stroke to position an uncrimped terminal between the die blocks. v
Changes in construction will occur to those skilled in .the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective against the prior art.
1. Apparatus for feeding and Lfor crimping connectors comprising: at least one set of reciprocable die blocks providing meeting faces `to define a connector receiving cavity, punch means movable through said die blocks and radially into said cavity, means for closing said die blocks, means yfor driving said pulses into said cavity after closure of said die blocks thereby to crimp a connector positioned between said die blocks, intermittently operable feeding means for feeding a connector to a position between said die blocks, and means for actuating said feeding means in timed sequence with operation of said means for closing said die blocks, said feeding means comprising means for feeding an axial succession of connectors, a plunger reciprocable along a path intersecting the feed path of said connectors and movable towards said cavity whereby upon a first reciprocation of said plunger, the leading one of said succession of connectors is toppled and upon a second reciprocation of said plunger the next v succeeding one of said connectors is toppled as the previously toppled connector is pushed to a position between said dies.
2. Apparatus for feeding and crimping a connector having a collar extending circumferentially therearound comprising: at least one set of die blocks reciprocable relatively towards and away from each other, said die blocks providing meeting faces to delinea connector receiving cavity, at least one punch in said die blocks movable therethrough towards said connector receiving cavity, means for actuating said punches after closure of said die blocks, means for delivering a succession of terminals one at atime to said die lblocks comprising a feed path leading from a 4mass of terminals, vibratory4 means for urging an axial succession of terminals alongV said path, a track extendingV from the end of said feed path, said track comprising a pair of rails spaced from each-other a distance slightly greater than the normal thickness of said terminals but less than the thickness of said terminals at their collars whereby said articles are retained from falling between said rails, said track being downwardly curved and having tripping means adjacent said curve whereby terminals travelling along said track are tripped and fall from said rails withthe end adjacent said collar leading, an inclined plate positioned beneath said track providing a groove extending from a point beneath said track, at least one tube having an inlet on said plate, said groove extending to said inlet thereby to convey a succession of terminals to said tube, said tube at its opposite end entering a chamber, and toppling and ejecting means reciprocable through said chamber operable upon one stroke thereof to topple the leading one of a succession of terminals in said tube and to position a, previously toppled terminal between said die blocks.
3. Apparatus for simultaneously attaching a terminal onto eachend of a conductor comprising a guide block having acentral camming means providing oppositely directed central camming surfaces, a die set on each side of said camming means, each of said die sets comprising a pair of die blocks, one of said die blocks being disposed adjacent to, .and the other of said die blocks being disposed remote from, one of said camming surfaces, a pair of movable camming blocks positioned one on each side of said central camming means and each providing a camming surface engageable with the one of said die blocks which is remote from its central-camming surface, resilient means normally maintaining said die blocks of each set in spaced-apart relationship, actuating means for simultaneously driving said movable camming blocks towards said central camming means thereby to move said die blocks into mating' relationship, `and punch means movable radially through at least one die block of each set to indent a terminal positioned between said die blocks whereby upon positioning of an uncrimped terminal between the blocks of each set of die blocks and upon insertion of the ends of a conductor into said terminals and actuation of said actuating means, terminals are secured to both ends of said conductor.
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