US2639075A - Apparatus for applying caps to containers - Google Patents

Description

J. w. KERLIN 2,639,075

APPARATUS FOR APPLYING CAPS TO CONTAINERS Flled July 2, 1952 INVENTOR John/WKerLin ATTORNEYS May 19, 1953 Patented May 19, 1 953 APPARATUS FOR APPLYING CAPS TO CONTAINERS John W. Kerlin, Teaneck, N. J assignor to Gen eral Foods Corporation, New York, N. Y., a. corporation of Delaware Application July 2, 1952, Serial No. 296,887

9 Claims.

This invention relates to improved apparatus for applying caps to containers such as cans, bottles and the like, and more particularly to apparatus for applying caps of the type that is secured or locked in container-closing position by downward pressure against the top of the cap.

Caps of the type mentioned above are well known in the art. For example, one such cap in widespread use has the general shape of an inverted cup, the bottom of which forms the top of the cap. The side or rim of the cup, which is usually slitted, then forms a depending skirt or flange surrounding the upper end of the neck of the container. The disc-like top of the cap is arranged so that when pressed down in the middle, it becomes somewhat concave and expands the flange so that the cap is loose on the container neck. On the other hand, downward pressure at or near the periphery of the top of the cap causes it to become somewhat convex, thus contracting thefiange or skirt tightly around the neck of the container. The invention is illustrated hereinafter with reference to caps of this type, but it will be understood that it is not restricted thereto.

In commercial operations in which caps of the above or similar type are used, the containers are usually conveyed in succession through filling mechanism and then past a feeding device where a cap is placed loosely on the neck of each container by feeding mechanism of various known types. Then the line of filled containers with the caps loosely in place thereon moves on to a cap closing station, where the successive containers are each brought into registry with a cap closing device the operation of which is synchronized with the conveying mechanism so that the desired downward pressure is applied to the top of each cap to close the same on the neck of the container. While such known arrangements are effective, the mechanisms required often are undesirably complicated and expensive in construction and operation.

One of the objects of the present invention is to provide a new and improved cap closing device or apparatus of the type mentioned above, which is extremely simple and inexpensive in construction and operation and yet completely effective and reliable in service.

Another object is to eliminate all registering and/or synchronizing mechanisms by making it unnecessary to stop the movement of the container at any fixed position relative to the closing station, or to synchronize the movement of the container with the operation of closing mechanism at the closing station.

A further object is to provide an improved cap closing device wherein the movement of the closing device is caused by, and the power required for the application of vertical closing pressure to the cap is derived from, the horizontal movement of the container itself.

Briefly described, apparatus embodying the invention comprises a pendulum-like cap-applying device depending from and swinging in a pendulum-like are about a horizontal or substantially horizontal pivot. Any suitable means such as a weight or a spring normally maintains said device at one end of its are which may be considered a starting position, and also returns said device to this point after a cap has been applied to a container. The cap-applying device swings above and in approximately the same plane with a line of caps placed loosely on the necks of a series of filled containers, said containers oving on a conveyor arranged so as to insure that the caps move in the right. line and at the right height to engage the applying device at its normal starting position. The path of travel of a cap as moved by the conveyor'thus constitutes a chord which intercepts the arc of swing of the capapplying device, the latter moving radially'in- Ward toward its pivot as it swings through the central portion of its arc and being provided with suitable yielding means to apply yielding closing pressure to the cap on the container. Continued movement of the container swings the device toward the opposite end of its arc until the cap disengages itself therefrom, the device then being free to return or to be returned to its starting position for engagement by the cap on the next container in the line.

One embodiment of the invention as described above has been illustrated in detail in the accompanying drawings, but it is to be understood that such drawings are for purposes of illustration only and are not to be taken as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings,

Fig. 1 is a perspective view of apparatus embodying the invention;

Fig. 2 is a detail view showing the central capapplying position of the apparatus;

Fig. 3 illustrates one suitable type of cap;

Fig. 4 is an enlarged-section illustrating the operation of the cap-applying device in'connection with a cap of the type shown in Fig. 3; and

Fig. 5 is a bottom plan view of said cap-applying device.

Referring first to Fig. 1,.a series of containers l0, here shown as gallon cans for syrup or like liquids, are arranged in succession and moved in a line by any suitable type of conveyor indicated generally at H and moving between suitable side rails l2. It will be understood that this conveyor may be one provided especially at the cap closing station, or it may be simply a portion of the usual conveyor which carries the containers through and away from the filling station (not shown). The conveyor ll may opcrate either continuously or intermittently as may be desired for the filling or other operations, without regard to the cap closing operation hereinafter described. When there is suflicient friction between the individual containers and the conveyor, the containers may simply rest on the conveyor without positive feeding action, but in the case of lighter containers such as bottles [3 (Fig. 2) it may be desirable to provide suitable feeding pockets [4 or like positive feeding means.

At any suitable point in their movement toward the cap closing station, the containers pass a cap feeding station at which a cap is placed loosely on the neck of each container. It will be understood that this operation may be accomplished manually if desired or by any known type of feeding means. It is indicated diagrammatically in dotted lines at the right-hand side of Fig. 1.

Figs. 3 and 4 illustrate in detail the type of cap preferably employed. The neck 1-5 of the container is provided with an enlarged bead I6 at its upper end which serves to strengthen the neck and also as a means for securing the cap in place. The cap itself comprises a disc-like flexible top I! provided with a depending peripheral flange or skirt I8 which is slitted as indicated in Figs. 1 and '2' and is. provided with inwardly turned projections [9 adapted to engage under the bead [-6 when the skirt I8 is contracted. As shown in Fig. 3, the top ll of the cap can be depressed into concave formation by centrally applied downward pressure, thus causing radial expansion of the skirt I 8 so that the cap rests loosely and removably on the neck of the container. This is the condition of the caps as they arrive at the closing station. By pressing downwardly on the periphery of the top of the cap, however, the disc I! shifts to a convex formation as illustrated in Fig. 4, thereby causing radial contraction of the skirt l8 around the bead IS, the projections l9 engaging under the bead and locking the cap in place.

The present invention resides primarily in an apparatus whereby the above described cap closing operation is performed automatically'on the series of containers in or l3 as they are moved along by the conveyor 1 I. As stated above, the cap-applying device is pivoted to swing about a substantially horizontal axis above the line of containers on the conveyor. This'may be accomplished by any suitable supporting framework, depending upon the type of equipment in question and the availability of other parts of the mechanism to serve as supports. For convenience, Fig. I simply shows a U-shaped frame comprising uprights 20 "mounted on the side rails l2 and connected at the top by a bridge piece 2|. A pivot rod or shaft 22 extends between the uprights 20 and provides a pivotal mounting for the hub '23 of a depending swinging arm 24 which carries the cap-applying device. Preferably the hub 23 is capable of some lateral displacement on the rod 22 so as to '4 accommodate slight deviations from exact alignment of the series of caps moving along with the conveyor H. Thus in the form shown, the hub 23 floats on the rod 22 between spaced collars 25.

The cap-applying device per se is mounted on the depending arm 24 to swing in pendulum fashion about the rod 22, and comprises a cap engaging head or chuck 26 that is slidable upwardly on the arm 24 against the compression of a coil spring 21, the lower end of which bears against the top of the head and the upper end of which is seated in a spring seat 28 secured to the arm 24. Normally the head 26 is maintained in the starting position shown in full lines in Fig. 1 and located at the end of the arc of swing in a direction toward the oncoming containers. This starting position can be defined by any suitable means limiting the swinging movement of the arm 24 in said direction. By way of example, Fig. 1 illustrates an arm 29 depending from the bridge piece 2| and provided with a suitable rubber bumper 30 or the like against which the head 26 is normally maintained by means such as a tension spring 3| interposed between the arm 24 and the arm 29.

The head or chuck 26 is provided with a downwardly opening cap-receiving recess which, in the starting position of the chuck described above, is so arranged that a cap on one of the moving containers enters the recess and engages and swings the chuck away from its starting position against the tension of the spring 3|. The exact shape of this recess will depend on the shape of the cap to be closed and on the location of the point or points at which the closing pressure is to be applied. Figs. 2 and 4 show a chuck or head designed particularly for a cap of the type shown in Fig. 3. It comprises a central recess 32, the arm 24 passing through the bottom of the recess and being provided with a head 33 within the recess which limits the outward movement thereon of the chuck 26. Toward the lower end of the chuck, the recess 32 is enlarged to provide a shoulder 34, and again enlarged to provide a second shoulder 35, as best seen in Fig. 4. outwardly of the shoulder 35, the internal diameter of the recess is suflicient to surround rather closely the cap on the container, the shoulder 35 thus bearing on the peripheral margin of the top of the cap to apply the desired downward closing pressure, andthe distance between the shoulder 35 and the shoulder 34 providing a space into which the convex portion of the closed cap projects freely as shown in Fig. 4.

Preferably the shape of the recess as above described is modified somewhat on the side away from the oncoming containers so as to facilitate the entry of a cap .into the recess and to insure proper closing engagement of the chuck with the cap. As best shown in Figs. 4 and 5, the shoulder 35 is routed out through approximately of its circumference on the side away from the oncoming containers, the ends of this shoulder merging into-an inclined conical surface 36 extending from the shoulder 34 to the end of the chuck. Thus as a loose cap approaches the chuck in its starting position, the forward portion of the expanded skirt l8 comes into engagement with the conical surface 36 and the moving container thus pushes the chuck away from its starting position. As this takes place, relative rotation between the chuck and the cap also occursat the same time that the two are being forced together. Disen gagement is therefore impossible, the chuck eventually being seated squarely on the cap at the center of its arc of swing as shown in Fig. 4, and the spring 21 being compressed by radially inward movement of the chuck to apply yielding pressure to the periphery of the cap throughout about 270 of its circumference.

In some cases it may also be desirable to provide suitable means to insure that the caps on the containers are in proper position as they reach the starting position of the chuck. It may also be desirable to provide means for guiding the swinging movement of the chuck itself. Both of these objectives can be accomplished by means such as a guide bar or rail 31 extending longitudinally above the line of containers on the conveyor, the chuck being slotted at 38 to swing back and forward relative to the bar 31. The end of the bar toward the oncoming containers is preferably bent upwardly as shown at 39 so that the loose caps move underneath the rail and are pressed downwardly to the proper position shown in Fig. 3 before they engage the chuck 26. It will be understood, of course, that the rail 31 can be mounted in any suitable manner. For convenience, Fig. 1. shows a supporting bracket 40 connecting one end of the rail 31 to the arm 29, and a supporting bracket 4| connecting the other end of the rail to the bridge piece 2!. may extend forwardly in the direction of movement of the containers to the full extent of the arc of "swing of the chuck for guiding the latter. The slots 38 are preferably somewhat wider than the rail 3'! in order to permit some lateral displacement of the chuck as mentioned above. During the return movement of the chuck to starting position, it can be held against the rail on either side by means such as a side spring 42 extending from the arm 24 to one of the side uprights 20, thus insuring return of the chuck to the same starting position and providing sufficient friction to prevent rebound from the bumper 30.

The operation of the invention will be clear from the foregoing description. It will be seen that the only operating mechanism required for the cap-applying device is the return spring 3| and the compression spring 21 or their equivalents. Otherwise the device swings like a pendulum about the pivot 22. The swinging of the pendulum away from its starting position is effected by virtue of the movement of the container itself and the engagement of the cap With the chuck, the power required for this movement and for the vertical compression of the spring 21 being supplied by the conveyor. After the cap has been snapped to closed position, the container continues to move onwardly until the closed cap disengages itself from the chuck which thereupon is returned to starting position by the spring 3 i. It is only necessary that the spacing between the successive containers on the conveyor, and/or the rate of movement of the conveyor, be regulated so that the chuck swings back to starting position before the next container reaches the starting position. Thus it is not necessary to stop the movement of the conveyor, although of course the invention can be used with an intermittently moving conveyor where desired for other reasons. No registering or synchronizing mechanism is necessary, and it makes no diiference whether the conveyor is full or empty, or whether the containers are placed thereon at regular intervals or at random. For all of these reasons, the device is extremely simple and inex- The rail 6* pensive inconstruction and operation, but yet completely eflective andreliable in service.

While only one embodiment of the invention has been described in detail above and illustrated in the drawings, it will be understood that the invention is not restricted to this embodiment but is capable of other mechanical forms, and also that various changes may be made in the form,

details of construction, and arrangement of the parts, all without departing from the spirit of the invention. Reference should therefore be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. Apparatus for applying container caps of the type closed by downward pressure applied to the top of the cap comprising conveyor means for moving a line of containers with caps placed loosely thereon, a chuck having a downwardly opening cap-receiving recess shaped to apply downward pressure to the top of a cap therein, means pivotally mounting said chuck to swing in a pendulum-like arc in substantially the same plane with the path of movement of said caps, said mounting means including resilient means yieldingly resisting radially inward movement of said chuck with respect to its pivot, means limiting the swinging of said chuck in the direction opposite to the direction of movement of said containers at a eap-receiving position, and means biasing said chuck toward said position, whereby the loose cap on a moving container engages the chuck at said position, moves it through the low point of its are with resulting closing of the cap by yieldingly applied pressure, and then disengages itself from the chuck for return of the latter to said cap-receiving position.

2. Apparatus as defined in claim 1, including a pivot member on which said chuck is mounted both for swinging and for displacement in an axial direction, and means on said member limiting the extent of such displacement, whereby the chuck can move laterally with respect to the line of moving caps on engagement by a cap that is out of line.

3. Apparatus as defined in claim 1, including a guide bar extending over and maintaining the loose caps in proper position on the moving containers to engage said chuck, said chuck being slotted for movement with a cap relative to said guide bar.

4. Apparatus as defined in claim 1, including a pivot member and a depending arm rotatably mounted on said member, said chuck being slidably mounted on the lower end of said arm, and resilient means interposed between said arm and chuck and yieldingly resisting radially inward movement of said chuck on said arm.

5. Apparatus for applying container caps of the type having a depending skirt surrounding the mouth of the container and contractible by downward pressure on a portion of the top of the cap, said apparatus comprising a pivot member having 2. depending arm rotatably mounted thereon, a head slidably mounted on and resiliently urged toward the lower end of said arm, said head having a cap-receiving recess shaped to apply downward pressure to the aforesaid portion of the top of a cap therein, means urging said arm to swing in one di ection and normally maintaining said head in a limited cap-receiving position, and a conveyor disposed to support and move a container in the opposite direction in a path such that a cap placed loosely on the container engages in said recess at said position, the continued movement of container by said conveyor causing.

said arm to swing through an arc with said head applying yielding pressure to the aforesaid portion of said cap.

6. Apparatus as defined in claim 5, the aforesaid portion of the cap comprising the-peripheral portion of its top, said recess being approximately cylindrical to a depth approximately that of said skirt and then decreasing in internal diameter to provide a shoulder engageable with said peripheral portion.

7. Apparatus as defined in claim 5, said shoulder and cylindrical portion of the recess being cut away on one side to provide an enlarged substantialiy conical surface for engagement by the leading portion of a cap on a container arriving at said cap-receiving position.

8. Apparatus as defined in claim 5, including a stationary bar extending longitudinally above said conveyor in position todepress the loose caps on the mouths of said containers as they approach said position, the walls of the recess in said head being notched to receive said bar.

9. Apparatus for applying container caps of the type having a depending skirt surrounding the mouth oiv the container and contractible by downwardpressure applied peripherally to the top of the cap, said apparatus comprising a horizontal pivot member having a depending arm rotatably mounted thereon, a head having a downwardly opening cap-receiving recess, said arm extending slidably through the bottom of said recess and having a head-retaining enlargement on its lower end, resilient means interposed between said head and said arm, a conveyor located to move a series of containers so that caps placed loosely thereon move in a substantially horizontal path intercepting a portion of the arc of swing of said head, means for limiting the swing of said head in one direction at the point of interception of its are by the oncoming caps on said containers, and means normally maintainin said head in said limiting position, said recess having an internal shoulder for applying yielding pressure to the periphery of acap as said head swings through the central portion of said intercepted arc.

JOHN W. KERLIN.

No references cited.

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