US2241721A - Article handling mechanism for wrapping machines - Google Patents

Description

W. HOPPE May 13, 1941.

ARTICLE HANDLING MECHANISM FOR WRAPPING MACHINES Filed May 1, 1939 3 Sheets-Sheet 1 I INVENTOR /V/z L ./,4 4/ #01 1 5 v I A TORN YS 5 Sheets-Sheet 2 INVENTOR W/L L IA M flo L" A ORN S W. HOPPE ARTICLE HANDLING MECHANISM FOR WRAPPING MACHINES Filed May 1 May 13, 1941.

W. HOPPE May 13, 1941.

ARTICLE HANDLING MECHANISM FOR WRAPPING MACHINES Filed May 1, 1 939 5 Shee'ts-Sheet 3 IIIIIIIIIIIII \\\\\\\\\\\\i lllmulllllillll INVENTORH W/u/AM //0PP I ORN Y5 Patented May 13, 1941 UNITED STATES Rd? ARTECLE HANDLING MECHANISM F63 WRAPPING MACHINES William Hoppc, Springfield, 'Masa', assignor to 'National Bread Wrapping Machine 00., SpringfieleL-Mass a corporation of Massachusetts Application May 1, 1939, Serial Nol 271,684

2 Claims.

This invention relates to improvements in mechanism for handling articles in wrapping machines, and has particular reference to article handling mechanism adapted to supply the articles to the machine and to convey the articles up to the point where they are associated with their wrappers.

In Wrapping machines of the types shown for example in the Smith and I-Ioppe Patent 1,953,195, April 3, 1934, and in the I-Ioppe Patent 2,043,375, June 9, 1936, the article is pushed against a wrapper sheet directly upon a vertically movable carrier or elevator. The wrapper is drawn circumferentially around the article by the movement of the latter onto, with, and off from the carrier. It has been customary in machines of this type to feed the articles to the machine by a cross-feed conveyor which delivered the articles to a position in front of the carrier from the side of the machine, the articles being carried into position in single file from which they were pushed laterally one at a time by a pusher associated with the carrier. For many purposes, particularly to permit the machine to be attended by only one operative, it is desirable to have the incoming articles arranged in a line directly under the wrapped articles delivered by the machine instead of having'the two lines at right angles to each other as in the patented machines referred to. Up to the present' time it has not been possible to accomplish this object, since the pusher which carries the articles onto the carrier would interfere with the incoming articles. Certain prior machines have fed the articles onto a carrier directly from the infeed conveyor without the intervention of a pusher, but this method is not applicable to the patented machines since it is impossible with this direct feed to reach the high speed of which the machines were capable when operated with the cross-feed conveyor for which they were designed.

The manner in which this problem has been solved by the present invention can best be understood in connection with the accompanying drawings, in which:

Fig. 1 is a fragmentary median section through a wrapping machine of the type illustrated in detail in the patents referred to, and in which the present invention has been incorporated; and Figs. 2 to 9 inclusive are diagrammatic views illustrating successive stages of the passage of an article to and through the machine.

As is fully described in the patents mentioned, the wrapping machine comprises a frame l upon which is mounted a carrier I I having vertical reciprocation from a lower loading station shown in Fig. 5 to an upper delivery station shown in Fi 8 in which the carrier is level with the floor 12 of a Wrapping channel. In the patented structures the lower position of the carrier was opposite the end of the infeed conveyor, from which the articles were carried successively onto the carrier by a reciprocating pusher I3. In the present case the lowerposition of the carrier brings its floor on a level with the floor of a second carrier or elevator Hi when the latter is at its uppermost level of reciprocation. This carrier I4 is mounted on suitable guides l5, and is connected by links [6 with arms ll pivoted to the frame at I 8 and rocked periodically by any suitable cam or linkage mechanism so that it moves from this uppermost position to a lower position shown in Fig. l in that timed relation with the other parts which will be described In its lowermost position the second carrier is level with the end of a table l9 along which the articles are pushed successively by flights 26 on a continuously moving endless conveyor 2|.

Bearing in mind the fact that the various elevators, pushers, and the like may be operated in any desired way, as for example by the mechanism shown in the patents mentioned, the operation of the improved mechanism will best be understood by considering the different positions of the elements as the article passes through the machine. In Fig. 1 the carrier [4 has reached its lowermost level, where it is substantially in line with the table l9 along which an article a is beingpushed by one of the flights 20. As shown by a comparison of Figs. 1 and 2, it is generally preferable to have the carrier de- 'scend to a level slightly below that of the table, so that it may startto rise before the article is completely seated upon it. By this means the rather excessive slowness at the start of the movement of most cam or linkage mechanisms does not interfere with the rapidity of movement with which the carrier moves fromoperativealignment with the table I 9 to its uppermost position.

Before the loaf has completely passed onto the carrier M the latter has acquired a considerable upward speed,'and as shown in Fig. 3 has become elevated a sufficient amount to allow the flight to pass underneath it. For this purpose the carrie'r'plate is preferably beveled as at 22 to avoid interference. The main carrier l I is meanwhile descending as shown in Fig. i, and by the means described in either of the cited patents the wrapper w is being positioned in, a substanhorizontal movement, carrying the article across the face of the carrier at such a rate that the article has picked up speed and may be transferred to the main carrier H at a high rate of speed when the two carriers come into alignment.

A distinction between the transfer of the article from the table E9 to the feeding carrier and the transfer from the latter to the main carrier should be noted. The invention is particularly applicable to bread wrapping machines in which the feeding-in conveyor ii is a prolongation of the delivery conveyor of the slicing machine, and in this case the spacing of the flights is fixed. Furthermore, the method of transfer of the loaf from the table 28 to the feeding carrier requires that the flight pass below the carrier immediately after it has positioned a loaf thereon. These two requirements necessitate that the flights travel at a steady rate and that they be of low height in order to avoid interference difliculties during the transfer. The steady rate requires a slower speed than would be eflicient in the transfer to the main carrier, for it is of prime importance to the efficiency of the wrapping machine that the time when the latter carrier is at rest at the bottom of its stroke be reduced to the minimum. The output of the machine is limited by the fastest motion required of any wrapping element during the entire cycle, and it is apparent that if one of these elements, such as the carrier H, be allowed to remain idle for a substantial period this delay must be made up by extra speed on the part of this or other elements during the remainder of the cycle of the machine. The pusher i3 is not subject to this limitation to a steady rate, and it is possible to concentrate its effective motion in a much smaller part of the cycle than where, as in the case of the transfer onto the feeding carrier, the pushing element is a steadily moving flight. For example, where in the case of a loaf nine inches wide it takes 180 of the machine cycle to complete the passage of the loaf onto the feeding carrier, this same loaf can easily be transferred by the pusher Hi to the main carrier in 110 of the machine cycle. The decrease in the amount of dwell that it is necessary to give the main carrier at the bottom of its stroke is obvious.

It was mentioned above that the requirements of the transfer by the flights 20 onto the feeding carrier M necessitated the use of flights having but slight height. the lowness 0f the flights is of no disadvantage, but similar conditions are not present in the transfer between the two carriers. As the loaf passes from the feeding carrier to the main carrier it contacts the wrapper w, which is held taut under a substantial resistance in order to insure the tightness of the Wrap around the loaf. In addition, the loaf clamps the wrapper between itself and a frictionally held backing plunger in order to grip the wrapper tightly enough to draw it out from its guiding and tensioning mechanism. Both of these resistances to the 01? ward motion of the loaf combine to require a pushing action on the loaf which is sufficiently centralized so that the loaf will not turn over or tilt. A low flight, as necessitated by the conditions of the transfer onto the feeding carrienis thus not suitable for the second transfer; and in a similar manner would prevent the economical use of flights to carry the loaf directly from the feeding conveyor onto the main carrier.

The completion of the transfer of the loaf When used in this transfer from the feeding carrier to the main carrier is shown in Fig. 5. It will there be seen that the pusher [3 need only move back a very small distance in order to clear the main carrier, and that it will cause no interference whatever with the descent of the feeding carrier, being wholly above the latter. The feeding carrier is thus in a condition to descend rapidly and to get into position for the reception of another loaf. In Fig. 6 it is shown in its descent, while the main carrier rises. When the latter carrier reaches the level of the floor of the wrapping channel the backing plunger 26 is struck by a swinging pusher 2'! which carries the loaf out of the carrier onto the wrapping channel as shown in Figs. '7 and 8. At this point the loaf is taken over by one of a series of pushers 28 on an endless conveyor more particularly described in the patent to Lyon 2,088,269, July 27, 1937. The particular wrapping operations, other than the initial bringing together of the article and wrapper discussed above, need not be described as they in themselves form no part of the present invention.

What I claim is:

1. Article handling mechanism for wrapping machines comprising a main carrier vertically reciprocable between an upper level in alignment with a wrapping channel and a lower transfer level, a feeding carrier vertically reciprocable between an upper level in alignment with the transfer level of the main carrier and a lower receiving level, said feeding carrier at its upper level being directly adjacent said main carrier, a transfer plunger horizontally reciprocable over the feeding carrier when the latter is at the transfer level to transfer an article from the feeding carrier directly to the main carrier and having a length of stroke substantially equal to the width of the widest article for which the machine is designed, conveying means having continuously moving spaced flights in a timed relation with the feeding carrier, the carrier being so timed with relation to the conveying means that the carrier is caused to descend below the level of the conveying means prior to the initiation of the transference of an article to the carrier, and the carrier is in motion upwardly during at least part of the transfer of an article thereupon;

2. In a wrapping machine, mechanism for raising an article from a delivery position at a lower level where the article has been delivered with all operations but wrapping performed, to an upper level in alignment with a wrapping channel, said mechanism comprising a main elevator vertically reciprocable between an intermediate level and the upper level, a feeding elevator reciprocable between the intermediate level and the lower level, the supporting surfaces of said elevators being side by side and co-planar when the elevators are at the intermediate level, means for moving said elevators vertically with a common period of dwell at the intermediate level, a transfer plunger at the intermediate level horizontally; reciprocable over the feeding elevator during the common period of dwell of both said elevators to transfer an article from the feeding elevator to the main elevator, and means in alignment with the feeding elevator when the latter is at the lower level to transferarticles successively to the feeding elevator.

WILLIAM HOPPE.

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