US3462914A

US3462914A - Box closing machine

Info

Publication number: US3462914A
Application number: US670925A
Authority: US
Inventors: Oskar Dorfmann
Original assignee: Federal Carton Corp
Current assignee: Federal Carton Corp
Priority date: 1967-09-27
Filing date: 1967-09-27
Publication date: 1969-08-26
Anticipated expiration: 1986-08-26

Description

6, 1969 o. DORFMANN 3,462,914

BOX CLOS ING MACHINE Filed 'Sept. 27", 1967 s Sheets-Sheet 1 FIG. 1

I03 I05 I ull INVENTOR OSKAR DORFMANN 4 I 9. BY mg v 1 g ATTORNEYS FiG. 9

1969 o. DORFMANN 3,462,914

BOX CLOSING MACHINE Filed Sept; 27. 19s? 5 Sheets-Sheet 2 To 0 /O \J a a Q 70 FIG. 2

6, 1969 o. DORFMANN 3,462,914

BOX CLOSING MACHINE Filed Sept. 27. 1967 5 Sheets-Sheet 5 Aug. 26, 1969 o. DORFMANN 3,462,914

BOX CLOSING MACHINE Filed Sept. 27. 1967 5 Sheets-Sheet 4 FIG. 4 2? 5112 MIHW M mmmmmmu H mum,

W/lfl/ ////M 6, 1969 o. DORFMANN 3,462,914

BOX CLOS ING MACHINE Filed Sept 27, 1967 5 Sheets-Sheet 5 FIG. 6

lllllllIlllmIIlIIlm-FT' i INVENTOR OSKAR DORFMANN ATTORN EYS United States Patent 3,462,914 BOX CLOSING MACHINE Oskar Dorfmann, North Bergen, N.J., assignor to Federal Carton Corporation, North Bergen, N.J., a corporation of New York Filed Sept. 27, 1967, Ser. No. 670,925 Int. Cl. B65b 7/24, 7/26 U.S. Cl. 53-201 11 Claims ABSTRACT OF THE DISCLOSURE Disclosed herein is a machine for closing an already erected and filled folding box, the box being of the type which has base, front, side, and rear walls together with a cover having side flaps and a front flap which cooperate respectively with the side and front walls of the box and particularly with slots in those walls to lock the cover in closed position. The boxes as delivered to the closing machine are, as stated, erected and filled, and the front flap of the cover is bent at an angle to the cover, the cover likewise being bent forwardly at a slight angle to the rear walls, but the side flaps remain in the plane of the main body of the cover. The machine of the disclosure operates to sequentially bend the cover front flap and side flaps into position at right angles to the main portion of the cover, to exert pressure on the side walls to open the slit provided therein for reception of the side cover flaps, to gradually lower the cover flap while maintaining the angular position of the walls, to then press against the side walls of the container and simultaneously and to a lesser extent, against the cover flaps to thus open the slits and permit the cover flap to enter them, and to finally press instantaneously against a tab on the box front wall to cause it to enter into a slit in the front cover flap. The machine is so constructed that by a simple and rapid replacement of a unit of mechanism, boxes of different capacity may be closed.

The invention herein is thus seen to be related to the folding box or carton art and particularly to machines for closing a folding box which has been previously erected and filled, ordinarily by automatic machinery, al though this is not essential. The particular box with which the machine of this invention is especially adapted to cooperate is a box of the type disclosed in my co-pending application, Ser. No. 646,083, filed June 14, 1967, now Patent No. 3,396,898, assigned to the assignee of this application.

Although not limited thereto, the box with which the machine is particularly adapted to cooperate is frequently used for the packaging of doughnuts. The box is made in a number of sizes and it is essential that the machine be readily adapted to close boxes of any of the sizes, since the exact number of packages of the difierent sizes (such for example, as six doughnut, eight doughnut and twelve-doughnut packages) cannot be determined in advance and the machine must therefore be capable of readily being converted for operation with the different sizes.

Heretofore, the general practice has been to erect the boxes by machine but to fill those boxes by hand and likewise to close them by hand. Whether the boxes are erected and filled by hand or by machine, the problem of closing is essentially the same and therefore the machine of this invention is hereinafter described in connection with the closing of a filled box and specifically a box filled with doughnuts.

As will be seen from the above, it is an object of the invention to provide a box closing machine which is simple, readily operated, and which is quickly adapted to close boxes of varying sizes to thus minimize the time 3,462,914 Patented Aug. 26, 1969 required to change from packaging in one size box to packaging in another.

It is another object of the invention to provide a machine for closing folding boxes which assures that the boxes will remain in their closed position and will be transportable without fear that the boxes will become open and their contents lost or damaged.

Other objects and features of the invention will appear when the following description is considered in connection with the appended drawings in which:

FIGURE 1 is an exploded perspective view of the box closing machine of the instant invention;

FIGURE 2 is a side-elevational view of the machine of FIGURE 1 showing certain linkages which were disconnected in FIGURE 1 in their connected, operating positions;

FIGURE 3 is a top-plan view of the machine of the instant invention;

FIGURE 4 is a front-elevational view of the machine of the instant invention;

FIGURE 5 is a fragmentary vertical cross-sectional view showing particularly the operation of the front flap folding means. This view is taken on the plane of the line 5-5 of FIGURE 4;

FIGURE 6 is a fragmentary horizontal cross-sectional view on the plane of the line 66 of FIGURE 4, showing the construction of a mechanism for positioning the side walls of the container and for preliminarily opening the slits in those side walls;

FIGURE 7 is a fragmentary horizontal cross-sectional view taken on the plane of the line 7-7 of FIGURE 2 and showing particularly the means for holding open the slits in the side walls of the box or container and causing the cover side flaps to be inserted therein;

FIGURE 8 is a fragmentary vertical cross-sectional view taken on the plane of the line 88 of FIGURE 7, and showing further detail of the side wall slit opening and side flap inserting means, and

FIGURE 9 is a fragmentary cross-sectional view showing the operation of a mechanism for pressing a tab on the front wall of a box into position to be inserted through a slit in the front cover flap.

Referring now to the drawings and particularly to FIG- URES 1 through 3 thereof, it will be seen that the machine comprises a table 1 0 suitably supported by any suitable means such as spaced legs 11, the top of the table being slotted as at 12. Beneath the table 10 is a conveyor comprising spaced chains 13, the conveyor being supported and driven in any suitable manner (not shown).

Fixed to corresponding longitudinally spaced links of the two chains 13 are the upright pusher members 14 (see particularly FIG. 2), which members have offsets 15 near their upper ends which cooperate with other portions of the mechanism. As will hereinafter appear, the pressure members 14 are provided with nylon pads 16 which likewise cooperate with other portions of the mechanism to exert folding action on the box cover.

Fixed to the table top 10 are the flat angle members 17 as well as the toggle type clamps 18 which, as will appear, serve to position and retain the folding head upon the table 10 in a predetermined position.

Also fixed to the table 10 is a fence member 20 which serves to stop a box conveyed against it by an auxiliary conveyor (not shown) in position to be moved forwardly (to the left, as seen in FIGURE 1) by the pusher members 14. Likewise fixed to the table top 10 is an upright member 21, which supports a shaft 22 which, as will be described hereinafter, serves to transmit oscillating motion to various of the operating members of the folding head.

The folding mechanism or head comprises front bridge member 23, a rear bridge member 24, base plates 25, and side frame members 26.

Mounted on the front bridge member 23 are

bearings

27 and 28, which support a shaft 29 for oscillation. Fixed to shaft 29 is an arm 30 having a hole 31 (FIG. 2) therein. Mounted on shaft 22 are arms, 33, 34 and 35.

As will be seen particularly when FIGURES 1 and 2 are compared, the folding head is placed upon the table 10, located by the angles 17 and clamped in position by the clamps 18. The arm 34 is connected by means of an adjustable link 36 (FIG. 2) to a suitably reciprocated member 39 which is driven at a rate coordinated with the movement of the chains 13 by means not shown. When the head has been placed in position, the

arms

30 and 33 are joined by means of a link 37, which link is permanently pivoted in the forked end of the arm 33, and is held in the forked end of the arm 30 by means of a removable pin 38.

Extending between the upright portions of the front and

rear bridge members

23 and 24, are the guide rails 40, one on either side of the folding head, which rails guide the boxes to and through the folding head as the conveyor chain moves. The front ends of the rails 40 flare outwardly, as indicated at 41, to assure proper positioning of the boxes as they are taken from the feed conveyor already mentioned. It should be noted that the guide rails 40 have a greater vertical extent at the rear of the folding head than at the front. Fixed to the upright portions of the front bridge 22, above the guide rails 40, are guide rails 42 (see FIG. 3), which guide rails cooperate with the box side walls to properly position them. Mounted at the forward end of each guide rail 40 is a resilient element 43, the rearward end of which is adjustable by means of a screw 44 so that these two elements bear against the upper portion of the side walls of the a box, guiding it into an exact position so that the cover side flaps may be folded at right angles to the cover, and serving also to break the side wall inwardly momentarily, as will be described shortly.

Mounted on the shaft 29 for rotation therewith is a folding member 45 for the cover side and front flaps. This folding member 45 has a fork shape and at the end of each prong of the fork is a rearwardly projecting member 46, each of which makes contact with one of the front corners of the box cover as the box is fed between the legs of the bridge member 22, thus forcing the front cover flap against the members 48 (FIG. 4) which are beveled on their forward surfaces and the flap of the box cover is forced to bend forwardly due to this striking of the flared folding members 48. At the same time, the side cover flaps are also forced to bend forwardly due to striking the flared forward ends of the folding members 47, the

members

47 and 48 being affixed to the bridge uprights and lower surface of the bridge horizontal, respectively.

Referring now particularly to FIGURE 5, it will be seen that the horizontal member 50 of the bridge 23 has a bore 51 therein, through which a plunger 52 extends, the plunger also extending through an opening in the angle 53 fixed to the upper surface of the bridge horizontal 50. A spring 54 extends between collar 55 on plunger 52 and the lower surface of the angle 53. At its upper end the plunger 52 carries a collar 56 adapted to be engaged by a fork 57 affixed to the arm 45. As will be seen, when the arm 45 is in its lower position, that is, when the box cover and side flaps are being folded as described above, the plunger is lifted by the fork 57.

Pivotally mounted centrally of the lower surface of the bridge horizontal 50 is a V-shaped member 58 which is urged to an upper position by means of a tension spring 60. When the member 45 is in its lowermost position, the member 58 is in its uppermost position, permitting the front cover flap to be placed at substantially right angles to the cover, while the cover is substantially still erect and in position against the folding elements 47. As the box is further advanced to the position shown in FIG- URE 5, the folding arm 45 returns to its uppermost position and in so doing, permits release of the plunger 52 which under urge of the superior spring 54 moves downwardly, forcing the folding member 58 against the front flap of the cover and causing it to slide down along the surface of the pad 16 on the upper surface of the folding member 14, and into substantial alignment with the offset 15 of that pad. It will be understood of course that the conveyor is moving in timed relationship to the movement of the arm 45 so that space is available for the flap to move along the nylon pad without at any time being forced by that pad.

Supported on the front and rear bridges is a cover closing member 61 having a central web 62 and side webs 63, the member being cut out as indicated at 64 (FIG. 3). Mounted on, or integral with the sides of member 61 is an inclined folding member 65 which is in effect merely a continuation of the lower inclined surface 66 of the side portion 63 of the guide member 61.

As seeen clearly in FIGURE 3, the side portions 63 of the member 61 are provided at their forward ends with extensions 67, the lower surfaces of which extensions, together with the lower surface of portion 68 of the central member of the guide member 61, extend substantially horizontally and serve to depress the cover of the box somewhat further than is shown in FIGURE 5 and to a position in which it is forced beneath the offset 15 of the two pusher members 14, holding it in this position by virtue of the horizontal extent of the undersurface of the central portion 62 of guide member 61, until further action has been performed, as will be described hereinafter.

Fixed to each of the base rails 25 of the folding head is a bracket 70 (FIGS. 1, 7, and 8). Each bracket has inwardly extending lugs 71 thereon, through which a pin 72 extends, the pin serving to pivotally mount a member 73, which member has integral therewith two

extensions

74 and 75 extending at an angle to the member 73 at different elevations. Member 73 is urged in a counterclockwise direction as seen in FIGURE 7, by means of a compression spring 76, which extends between the bracket 72 and the forward end of the member 73. Threaded into an aperture in the bracket 70 is a screw 77, the rear end of which serves to limit the counterclockwise movement of the member 73.

Also threaded into the bracket 70 is a second screw 78 which extends beneath member 73 and bears against the guide rail 40, thus serving as an adjustment to slightly bow the guide rail and assure that the box is held centrally at the time when the

members

74 and 75 are operating thereon.

Referring now particularly to FIGURE 7, it will be seen that the member 75 is provided with a curved camming surface 80 which bears against the side wall of the box, causing that wall to be bowed inwardly to thus open the slit formed in the inner side wall portion of the box, the opening being shown in exaggerated form at 106 in FIG. 7. The curved forward portion of the member 74 extends into a horizontal slot in the upper guide rail 42 and is curved to cooperate with the box cover side flaps to force these side flaps inwardly so that they enter into the now open slit, being compelled to lie inwardly of the lower front portion of the box side wall 'below the area of a slot. As these actions are taking place, the conveyor is of course moving the box rearwardly and the inclined lower surfaces of the members 65 cause the box cover to be gradually lowered as the cover rides along the inclines indicated at 82 in FIGURE 2.

To the rear of the brackets 70, the lower surface of the members 65 of the closing member 61 against extends horizontally for a slight distance, as indicated at 83 in FIGURE 2. Beyond that point the side guide members 63 again incline downwardly toward the rear and are thus effective to push the covers of the boxes downwardly, with the side flaps of the cover penetrating further into the slits, the front flaps of the covers continuing to cooperate with the nylon pads to assure that the front flaps will lie within the front wall of the box.

Shortly after the box has passed the initial point of the further inclined surface of the guide members 63, shaft 22 is caused to oscillate, carrying with it the arm 84. This arm 84 is, when the folding head is installed on the table 10, rotated about shaft 22, so that the aperture 87 therein (see FIG. 1) is placed in alignment with the aperture 88 in the arm 35, after which the pin 90 is inserted through the aligned openings. Thus the arm 84 is caused to oscillate simultaneously with the oscillation of the arm 45. Arm 84 carries at its own end a pin 91 which is adjustable, being threaded in an opening in the end of the arm. This pin 91 serves to strike a tab 109 formed in the front wall 101 of the box and cause it to enter a slit 110 in the front cover flap (FIGS. 1 and 9).

As the pusher members 14 move the box to the rear of the folding head, the cover continues to ride down the inclined portion of the side rails 63 of member 61, finally encountering the more steeply inclined portions 63a fixed to or integral with rails 61 and causing the cover to be fully closed, and the box in discharged.

Although the foregoing description is believed to make obvious the mode of operation of the machine, the operation to close the box will be summarized briefly at this time.

Boxes are placed on a conveyor running at right angles to the conveyor heretofore described, and not shown in FIGURE 1, and are moved along that conveyor, which as seen in FIGURE 1, has guiding rods 99 associated therewith, these rods being in position to cause the front cover flap 108 to be bent slightly along the score line joining it to the cover, and to likewise cause the cover 103 to be bent slightly forwardly along a score line joining it to the rear wall 102 of the box, the box being filled with doughtnuts, as indicated at 98.

The box is then in position on the table to be engaged by the lower rearwardly facing portions of the pusher arms 14, which move the box beneath the forward bridge 23 with the cover substantially erect and the front cover flap 108 extending at a slight angle thereto.

As the conveyor carries the box beneath the bridge, the folding arm 45 lowers and the rearwardy extending projections 46 thereof engage the upper, forward corners of the box cover 103 (FIG. 9), forcing the front flap 108 to assume a position at right angles to the cover 103 and the side flap 107 (FIG. 1) to likewise take a position at right angles to the cover. Shortly thereafter, the arm 45 is raised, resulting in the folding member 58 pushing the front flap into a position where it rests against the lower portions of the pads 16 on the pusher members 14, after which, as the conveyor moves toward the rear, the box cover is lowered into a position where the forward edge of the front flap is lowered into the offset portion of the pusher pads 'by virtue of the cover riding along slightly inclined portions of the upper guide member 61 and specifically along the lower surfaces of the central member 62 and of the inwardly extending portions 67 of side rails 63.

As the box moves further to the rear, the side flaps are held in position by means of the upper guide rails 42 and as the box moves into the vicinity of the brackets 70-, the curved surfaces 80 of the pivoted members 73 engage the upper edges of the corresponding side wall portions 104, causing those portions and the portions of side walls 105 above the slits 106 to bend inwardly, thus opening the slits. When the slits are thus fully open, curved portions 81 of the extensions 74 forces the cover side flaps 107 inwardly so that as the cover engages an inclined portion of the guide member 61, as previously described, the ends of the side flaps enter the slits 106.

As the box continues its motion toward the rear of the table 10, the arm 84 moves in a clockwise direction and instantaneously strikes the tab of the front wall, causing it to move to the rear and engages a slit in the front cover flap, the cover simultaneously of course engaging the inclined rear portion of the side rails 63 to cause lowering of the cover with the flap 109 entered through the slit 110, the cover thereafter being fully lowered and the filled and closed box being discharged. It will be understood of course that normally a discharge conveyor would be utilized to take the filled boxes from the rear of the closing machine to a station at which they would, either by hand or automatically, be packed into cartons or otherwise prepared for shipment.

As was previously indicated, the machine of this invention is adapted to close boxes of varying sizes, as for example, doughnut boxes capable of containing six, eight, or twelve doughnuts. To accomplish this, it is only necessary that the folding head be removed and replaced with one of the desired size, the mechanisms of the various heads being identical save for the spacing of the various elements to accommodate boxes of the corresponding sizes. In each case the operating mechanisms are readily disconnected and connected by use of the removable links and thus no appreciable downtime is involved in shifting from one size box to another.

While a preferred embodiment of the invention has been described, it will be understood that variations of many of the elements are possible and I wish therefore not to be limited by the foregoing description but on the contrary only by the claims granted to me.

What is claimed is:

1. In a machine for closing erected and filled boxes, in combination; a table; means for conveying boxes along said table; a drive mechanism mounted on said table; a folding head comprising spaced transversely extending front and rear bridge members and longitudinally extending guide rails jointing said bridge members for guiding boxes through said head under drive of said conveying means, an oscillatory member for folding box cover side and front flanges into position at right angles to each other and to the box cover, means for engaging the side walls of a box to prepare openings to receive the cover side flaps and means for closing the cover as the box moves through said folding head; means for clamping said folding head to said table top and means for detachably interconnecting said drive means and said oscillatory member to thereby drive said members in timed relationship to said conveyor means.

2. A machine as claimed in claim 1 wherein said folding head additionally comprises base members joining said bridge members, and longitudinally extending frame members joining said bridge members, and wherein locating members are mounted on said table for engagement with said base members to position said head to be clamped in position to render said drive mechanism and oscillatory members readily interconnected and in alignment with said conveyor means.

3. A machine as claimed in claim 1 wherein said oscillatory member comprises a shaft mounted on one of said bridge members and extending transversely of said table, an arm fixed to said shaft for movement therewith, projections on said arm for engaging a box cover as the box passes beneath said bridge and wherein folding members are fixed to the bridge and uprights and horizontal portions adjacent the juncture thereof to cooperate with said oscillatory arm projections to fold the box cover side and front flaps.

4. A machine as claimed in claim 1 wherein said drive mechanism additionally comprises a support mounted on said table top, a shaft journaled in said support, said shaft extending transversely of said table top and above the folding head, an arm detachably fixed to said shaft for oscillation therewith and means on said arm for momentarily engaging a tab on the front wall of a box as it passes through said folding head to cause the tab to enter a slit in the front cover flap as the cover is closed.

5. A machine as claimed in claim 1 wherein said conveyor means comprises box pusher members extending upwardly from said table top and having offset portions at substantially the height of the box front wall and wherein a cover front flap positioning member is pivotally mounted on the undersurface of said front bridge member, said cover flap positioning member being actuated by said oscillatory member to retain said front flap at substantially right angles to the cover as said cover is partially lowered, whereby the edge of the flap slides along said pusher members and lies adjacent said offsets.

6. A machine as claimed in'claim 1 wherein camming members are provided at each side of said folding head intermediate said bridges, said camming member being resiliently urged inwardly, said camming members having camming surfaces adapted to engage the upper portions of the side walls of boxes to press them inwardly and open slits formed therein, said camming members having additional camming surfaces adapted to press against the cover side flaps and cause the ends thereof to pass through the opened slits and between the upper and lower portions of the box side walls.

7. A machine as claimed in claim 1 wherein said front and rear bridged members have mounted thereon a cover closing member having cover engaging means including horizontal portions and portions inclined downwardly in the direction of box movement from said front to said rear bridge whereby the box cover is caused to move toward closed position as the cover front flap is positioned to enter behind the front wall and said openings are prepared to receive the leading edges of the cover side flaps.

8. A machine as claimed in claim 1 wherein said guide rails have forwardly flared terminal portions adjacent to and ahead of said front bridge in the direction of movement of said conveyor means and wherein resilient box side wall engaging means are mounted on said guide rails immediately forward of said front bridge, said guide rail portions serving to center boxes beneath said bridge and said resilient means serving to bend the side walls inwardly about their junctures with the front and rear walls to aid in preparing said slits.

9. A machine a claimed in claim 6 wherein means are mounted adjacent said caming means engaging said longitudinally extending guide rails for bowing said side rails to assure proper centering of boxes at the time when said camming means are operating to enter the side flaps through said openings.

10. In a machine for closing erected and filled boxes of the type described, in combination a table having a longitudinally extending slot therein, a conveyor means mounted beneath said table and having box pusher arms extending upwardly therefrom through said slit, a folding head detachably mounted on said table top, said folding head comprising front and rear bridge members extending transversely of said table and conveyor means, guide rails mounted on the uprights of said front and rear bridge members, means mounted on said front bridge member to guide a box beneath said bridge and between said guide rails under drive of said pusher arms, an oscillatable arm having means for engaging the cover of a box adjacent the front corners thereof as the box is driven beneath said front bridge, means mounted on said bridge at the juncture of the bridge uprights and horizontal to cooperate with said oscillatable member to bend the front and side cover flaps at substantially right angles to each other and the cover as a box is moved beneath said front bridge, cover lowering means comprising partially horizontal and partially inclined surfaces protruding between said front and rear bridges, both engaging said cover means as a box passes beneath said bridge to move said cover toward closed position, means pivotally mounted beneath said bridge between said flap folding members to engage said cover front flap centrally thereof to maintain said flap in said right angle position during initial lowering thereof, camming means mounted between said bridges and adjacent said guide rails, said camming means being resiliently urged against box side walls to open slits therein and against box cover side flaps to guide said flaps into the opened slits as the cover is lowered by inclined portions of said cover lowering means, and a second oscillatable arm mounted on said table adjacent said rear bridge and extending between said guide rails for movement to engage a tab on the front wall of a box as said cover is additionally lowered by said lowering means to cause the box tab to enter a slit in the box cover front flap.

11. In a machine for closing erected and filled boxes of the type described, in combination a table having a longitudinally extending slot therein, a conveyor means mounted beneath said table and having box pusher arms extending upwardly therefrom through said slit, a folding head detachebly mounted on said table top, said folding head comprising front and rear bridge members extending transversely of said table and conveyor means, guide rails mounted on the uprights of said front and rear bridge members, means mounted on said front bridge member to guide a box beneath said bridge and between said guide rails under drive of said pusher arms, an oscillatable arm having means for engaging the cover of a box adjacent the front corners thereof as the box is driven beneath said front bridge, means mounted on said bridge at the juncture of the bridge uprights and horizontal to cooperate with said oscillatable member to bend the front and side cover fiaps at substantially right angles to each other and the cover as a box is moved beneath said front bridge, cover lowering means comprising partially horizontal and partially inclined surfaces protruding between said front and rear bridges for engaging said cover means as a box passes beneath said bridge to move said cover toward closed position, means pivotally mounted beneath said bridge between said flap folding members to engage said cover front flap centrally thereof to maintain said flap in said right angle position during initial lowering thereof, camming means mounted between said bridges and adjacent said guide rails, said camming means being resiliently urged against box side walls to open slits therein and against box cover side flaps to guide said flaps into the opened slits as the cover is lowered by inclined portions of said cover lowering means, a second oscillatable arm mounted on said table adjacent said rear bridge and extending between said guide rails for movement to engage a tab on the front wall of a box as said cover is additionally lowered by said lowering means to cause the box tab to enter a slit in the box cover front flap, drive means to oscillate said first and second oscillatable means, said drive means comprising a shaft mounting each said oscillatable means, an arm fixed to each said shaft, a link detachably engaging said arms, means for actuating said drive means in timed relationship with said conveyor means and means for locking said tab engaging means to said shaft in operating position and releasing it therefrom, said release together with detachment of said link from said first oscillatable means providing for removal and replacement of said folding head.

References Cited UNITED STATES PATENTS 2,441,410 5/1948 Guyer et a1 53376 X 2,660,012 11/1953 Boyce et al 53 -376 TRAVIS S. MCGEHEE, Primary Examiner US. Cl. X.R.