US 3451188 A
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Description (OCR text may contain errors)
June 1969 PTLUGINBUHL ETAL 3,451,188 APPARATUS FOR AUTOMATICALLY CONTROLLING THE FEED 0F A MATERIAL STRIP TO A PROCESSING MACHINE' Filed Aug. 5, 1966 A Sheet June24, 1969 P. LUGINBUHL E APPARATUS FOR AUTOMATICALLY CONTROLLING THE FEED OF A MATERIAL STRIP TO A PROCESSING MACHINE Filed Aug. 5. 1966 Z of 2 Sheet NW mm u w O 0.9 I: & m
United States Patent US. Cl. 53-73 4 Claims ABSTRACT OF THE DISCLOSURE and when the first switch is closed and drives the motor of the packaging machine, the other two switches are open.
The present invention relates toan apparatus for the automatic control of the feed of a material stripto a processing machine.
Chocolate bars are normally enveloped air-tightinan aluminium foil and are subsequently provided with an additional paper envelope. The entire packaging process is carried out fully automatically by a packaging machine. There may arise the case where, e.g., owing to a failure of the machine or owing to the exhaustion of the aluminium-foil reserve, chocolate bars issue from the machine which has been provided with a paper envelope only. Since the absence of the aluminium foil cannot be directly detected from the outside, there exists the danger that such bars will be put on sale, which is undesirable for hygienical and aesthetic reasons. The fat contained in the chocolate penetrates the paper envelope after a certain time, so that the envelope will show grease spots.
The invention has for object the creation of an apparatus, which prevents the occurrence of the aforedescribed defects.
According to the present invention an apparatus for automatically controlling the feed of a material strip to a processing machine, more especially the feed of an enveloping-material strip to a packaging machine, comprises means influenced by objects fed to said apparatus controlling the advance of the material strip and means which effect the stopping of the machine when the controlling means detect an abnormality in the advance of the material strip.
The invention will be described further, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematical side elevation of one form of apparatus according to the invention;
FIG. 2 is a section taken along the line II-II. in FIG. 1;
FIGS. 3 to 5 show different operational positions of three switches provided on the apparatus;
FIG. 6 shows, schematically, a side elevation of a second form of apparatus according to the invention, and
I provided on the apparatus.
FIG. 7 illustrates a detail of the apparatus according to FIG. 6, with a diagram of the three electrical switches It The apparatus shown in FIG. 1 includes a conveyor belt 1 having an aperture 2, into which engages a sensor 3 which is linked to a pivotable pawl 4. The conveyor belt 1 carries bar-shaped objects 5, e.g., chocolate bars, which are guided over the aperture 2 to a first processing position, here not shown, where they are enveloped in a manner per se known in an aluminium foil 6. This foil 6 is drawn off a storage roll 7, and is guided over a first 7 guide roller 8 and a second guide roller 9 to a table 10.
The roller 9 is supported by hearing pins 26 which engage inserts 27, one at each end of the roller. The insert 27 hastwo parallel discs 27a, 27b, between which engages the upper end of a lever 19. A continuously rotating feed roller 12, whose contact surface is flush with the surface of the table 10 is arranged in a slot 11 in the table. Directly above the fed roller 12 an applicator roller 14 is arranged on a pivotably mounted lever 13. The advance of the aluminium foil is effected by applying the roller 14 against the roller 12, whereby the foil 6 located between the two rollers is moved in the direction of rotation of the roller 12.
The lever 13 is linked by a bar 15 with an arm 16a of a three-armed lever 16, which is pivotable about an axle 17. A roller 18 is mounted at the end of the arm 16a,
and bears against the lever 19. A stationary rod 20 passes through a slot 19b in the lever 19, and the lever is held in the position drawn in full lines by a spring 21. The arm 16b of the lever 16 carries a roller 22 hearing against a cam plate 23, which in turn is mounted on a rotatable shaft 25. The shaft 25 further carries a cam disc 24, which acts on an electrical switch C. The arm 16c of lever 16 cooperates on one hand with the pawl 4 and on the other hand actuates an electrical switch B. A further electrical i switch A is actuated by the lever 19. As FIG. 3 shows,
the three switches A, B, C are arranged in parallel in the circuit of a drive motor of the packaging machine, which motor also drives the shaft 25 and the roller 12. The switch A is open in its rest position, whilst the switches B and C are closed in the rest position, as illustrated in FIG. 3, which corresponds to the position of the individual parts as shown in FIG. 1.
The apparatus operates as follows:
When the shaft 25 rotates, the lever 16 is pivoted in a clockwise direction, as soon as the roller 22 passes from the range of the cam plate zone having the larger radius R into the zone with the smaller radius r. This pivotal movement however can take place only if an object 5 actuates the sensor 3, so that the pawl 4 releases the arm 16c. The pivoting of the lever 16 initiates the following operations:
(a) The roller 14 is pressed against the roller 12 and the foil 6 located between the rollers is advanced;
(b) Owing to the tractive force of the foil 6 the roller 9 is rotated. Since the roller 18 has ceased to support the lever 19 and the latter therefore simply bears, under the traction of spring 21, with its edge 19a on the insert 27, it is pivoted into the position drawn in chain dotted lines when the roller 9 with its insert 27 rotates, in which position it rests on two stops 28, 29. Owing to the rotation'of the insert 27, the edge 19a of lever 19 rolls along the insert 27;
(c) The switches B and A are actuated, B is opened, A is closed. The rotation of the cam disc 24 further opens the switch C. FIG. 4 shows the position of the three switches when the foil is advanced. The current is supplied to the driving motor through the switch A. The resetting of the lever 19 into its initial position is effected by the cam plate 23 on further rotation of the shaft 25, by means of lever 16 and roller 18. This also causes lever 19 to release the switch A, which returns into its OFF position. Simultaneously the arm 16c releases the switch B, which returns into its ON position.
In the case where no object 5 moves along the conveyor belt 1 and over the aperture 2, the pawl 4 prevents a pivotal movement of the lever 16. Switch B then remains effective and the machine continues to run. However, the foil 6 is not advanced.
In the case where, e.g., no foil remains, and thus no advance can take place, the roller 9 is not rotated. The lever 19 thus remains in its position drawn in full lines, even though it ceases to be supported by the roller 18, since it rests with its edge 19a on the stationary insert 27 under the traction of spring 21. The switch A is thus not activated, while the switches B and C are switched off. In this case, as shown in FIG. 5, all three switches are open and the machine is stopped.
The embodiment according to FIGS. 6 and 7 difiers from the embodiment described in the foregoing only in that the switch A is actuated not by a lever 19 but by a generator 30 driven by the guide roller 9. As FIG. 6 shows, the rotor of an electrical generator is linked with the guide roller 9; the latter supplies driving current to a relay 31 linked with an amplifier, which relay closes the switch A when energized by the generator 30. As FIG. 7 shows, the two other switches B and C are connected in parallel to the switch A.
The mode of functioning is exactly the same as in the first form of embodiment.
1. An apparatus for automatically controlling the feed of a material strip to a processing machine, more especially the feed of an enveloping-material strip to a packaging machine, comprising an advancing mechanism for the material strip, a three-armed lever influenced by objects fed to said machine which periodically executes a pivotal movement, drive means for said lever, an arm of the lever controlling said advancing mechanism, a first switch means having a pivotable actuating lever releasable simultaneously with said advance, said actuating lever being pivoted by an advance movement of the strip, a second switch means actuated by said three-armed lever during its pivotal movement and a'third switch means actuated periodically by the drive means of said lever, the whole being arranged in such a manner that the first switch means controlled by the actuating lever admits current to the drive motor of the processing machine during a period in which the two other switch means have interrupted the supply of current. v
2. An apparatus according to claim 1 comprising a conveyor track and a blocking device controlled by the objects which prevents the pivotal movement of the threearmed lever in the absence of an object at a certain region of a conveyor track.
3. An apparatus according to claim 1 in which a guide roller driven by the material strip during its advance movement operates the actuating lever of the first switch means.
4. An apparatus for automatically controlling the feed of a material strip to a processing machine, more especially the feed of an enveloping-material strip to a packaging machine, comprising an advancing mechanism for the material strip, a three-armed lever controlling said advancing mechanism, a first switch means, a second arm of the lever actuating said first switch means to interrupt the supply of current to a drive motor of the processing machine, a second switch means, drive means for said lever periodically actuating said second switch means to also interrupt the supply of current to said motor, a roller driven by the advance movement of the material strip, a current generator connected to said roller, and third switch means actuated by said generator to ensure the fiow of current to the motor when said two other switch means are open.
References Cited UNITED STATES PATENTS 2,668,404 2/1954 Barefoot 5355 THERON E. CONDON, Primary Examiner. R. L. SPRUILL, Assistant Examiner.