US2561107A - Electrical control apparatus - Google Patents

Description

July 17, 1951 R- J. GAUBERT ELECTRICAL CONTROL APPARATUS Filed Oct. 4, 1949 FJZE E INVENTOR Pane J Gauberl ATTORNEYS Patented July 17, 1951 UNITED STATES PATENT FF ICE ELECTRICAL CONTROL APPARATUS Rene J. -Gauber t, Oakland, Caliil, assignor to fSimplexfPa'ckaging Machinery, Inc., Oakland,

Calif a corporation of California Application October 4, 1949, Serial'No. 119,516

Claims.

This invention relates generally to electrical control apparatus for use in conjunction witha movable web of material like cellophane, Pliofilm, or polyethylene.

As is well known to those familiar with bag making and wrapping machinery, materials like cellophane, Pliofilm, or polyethylene are supplied in roll form to provide a long continuous web. In many instances the materials are printed for the purpose of identification, advertising, etc, and. in such cases it is necessary to employ some type of control to compensate for errors in printing, errors in feeding of the machine, stretching of materials, etc., so that the printed matter remains in the desired position relative to the material after the material has been out. When the rolls of material are printed, it is customary to also print a so-called registration mark at spaced intervals along one margin. The spacing between these marks corresponds to the lengths into which the material will be eventually cut. The machines which employ such material are provided with electrical control means of the electric eye or photoelectric type, and the arrangement is such that the registration markings intercept the light beam of the electric eye to start or stop certain operations. By way of example reference can be made to my Patent No. 2,347,902 which illustrates an automatic bag making machine using a continuous web of-material like cellophane, Pliofilm, or polyethylene. Photoelectric means is utilized in conjunction with registration markings on one margin of the web to control intermittent feeding of the web. When a marking intercepts the light beam the feed means is disabled until certain bag making operations are completed, after which the feed means is made active to again move the web, and the circuit controlled by the electric eye is rearmed or reconditioned for subsequent tripping. By the use of such control means it is possible to correlate the length of the bags with the printing upon the web, whereby the printing is properly located on each bag.

While the electric eye has been used with good results in the type of machine described above, it has been found that the servicing required is excessive, and that any repairs or readjustments of the apparatus generally require the services of an electrical technician. In addition in many instances the operation of such apparatus is not entirely satisfactory, due possibly to erratic characteristics of the photoelectric tubes. A further disadvantage is that the initial cost is excessive, due to the electronic amplifying equipment required.

In "general it is an object of the invention to provide electrical means which can be employed to take 'the place of the electric eye type of equipment described above, and which'will make possible reliable operation with freedom from operating difficulties.

An additional object of the invention is to provide control apparatus of the above character which will be relatively low in'initial cost and simple to install and operate.

Additional objects of the invention will appear fromthe following description in which the preferred embodiment of the invention has been set forth in detail in conjunctionwith the accompanying drawings.

Referring tot-hedrawings- Figure '1 is aside elevational view, partlyin section, illustrating a portion of the ,machine shown in my Patent-No. 2,347,902-but with my new-control apparatus applied thereto.

Figure 2 is -an enlarged view illustrating the control apparatus includedinFigure-l.

Figure 313 a planviewof the apparatus illustrated inFigure 2.

'Figure 4 is a circuit diagram'illustratingone type of'circuitwhich can be utilized in conjunction with'my apparatus.

--Figure 5 illustrates a modified type of circuit.

Figure- 6' is-an enla-rged'detailin section, serving to illustrate theoperation of my apparatus.

'In Figures 1 'to 3 of the drawing, 'myapparatus has been illustrated in conjunction with parts of a bag making machine like that illus trated inmy-Patent 2,347,902. Thus bracket 10 represents a part extending rearwardly from the main frame of the machineisee-bracket 38,*Fig. 3a of Patent 2,347,902), and serves to mount a horizontally extending roller or guide rod I I, over which the web [2 passes. The roll from which the web-extends-is'located below-the parts illustrated, and from this roll the Web first passes over the guide roller l3, beneath the vertically movable take-up roller or rod 14, and from thence over the roller II. From the roller the web can extend over the rollers l6 and I7, and'from thence to-the' working-table of the machine. The rol1er l6- can be carriedby the angularly adjustable arms l8.

The'parts just described are all incorporated in :the machine as illustrated in my Patent 2,347,902. However in that instance a photoelectric tubeor electric eye is utilized in conjunction with theweb, and is customarily located-between the guide rollers-H and I4. The'photoelectric eye cooperates with indicia 0r markings [9, which are applied by a printing process, and which pro- 3 vide relatively opaque spots for intercepting the light beam of the photoelectric eye.

The indicia |9 are applied to the web of material by a suitable printing process, making use of fast drying inks which are sold commercially for this purpose. Very frequently two colors, such as red and yellow, or red and green, are applied one over the other, to increase the degree of opacity. The inks employed are relatively tenacious in resisting scratching or scraping, and make use of a resinous binder, together with a finely divided pigment and a fast drying solvent. The thickness of such printed markings may be of the order of 0.0002 inch whereas the thickness of the web of material itself may be of the order of 0.001 inch. Thus in the example just given, the total thickness of the material plus the markings is of the order of 0.0012 inch.

The present invention can be predicated upon my discovery that the difference in thickness between the web of material, and the material plus the thickness of the printed marking, can be used for the direct mechanical operation of electrical contacts. Thus I have found that when the margin of the web is caused to pass between anvils having opposed parallel faces, and with the spacing between the anvils slightly greater than the thickness of the material, but less than the thickness of the material plus that of the markings, the markings can be drawn between the anvils but with considerable mechanical resistance or drag. The amount of this resistance can be controlled by adjusting the spacing between the anvils, and it can be made ample for mechanical operation of the electrical contacts, without causing tearing or other mutilation of the material.

Referring again to Figures 1 to 3 of the drawing, I have shown a pair of anvils 2| and 22 which are disposed on opposite sides of the web I2, and

along the margin in line with the path of movement of the indicia or markings I9. I have found it satisfactory to use the anvils of a thickness gauging micrometer 23, which has the usual knurled barrel 24 for adjusting the distance between the anvils 2| and 22. It is desirable that the micrometer be provided with a locking nut 26, so that the movable anvil 2| can be locked in any desired adjusted position.

The body 21 of the micrometer is shown secured by clamp 28 to one end of a lever 29. This lever is fulcrumed by pivot pins 3| to a supporting bracket 32. The bracket is in turn attached to some convenient part of the machine frame, such as the cross-bracing rod 33.

The bracket 32 also carries a plate 34, upon which the electrical switch 36 is mounted. This switch can be of the type having an actuating member 31 which extends to the exterior of the switch casing, and which when moved a small amount causes snap action of the interior electrical contact between open and closed positions. The actuator member 31 is spring pressed toward the exterior of the switch casing and is shown in contact with the lever 29, so that when the lever is rocked, the contacts are operated. A suitable compression spring 38, the tension of which can be adjusted, is interposed between bar 34 and the free end of the lever 29, so that the lever is urged in a clockwise direction as viewed in Figure For the position illustrated in Figure 3 it is assumed that the web is moved upwardly. Adjustable limiting abutments 39 and 4| are also mounted upon the bar 34, and serve to limit the rocking movement of the lever 29.

As viewed in Figure 3 the micrometer 23 is normally in its lowermost position, and for that position the contacts of the switch 36 may be either open or closed. Assuming however that the contacts are normally open, when the lever 29 is swung in a counterclockwise direction, or in other words, when the micrometer 23 is moved upwardly a limited amount against the thrust of spring 38, the switch 36 is operated to close the contacts.

Figure 6 serves to illustrate the relationship of the anvils 2| and 22 to the web l2. It will be noted that the opposed faces of the anvils are in accurate parallelism, and they appear to be substantially in contact with the surfaces of the web. It is preferable to bevel or round the edges of the anvils as indicated at 42, to minimize scratching or tearing of the material. It is also preferable that the anvils, or at least the faces 01 the same, be of relatively hard material, and that they be provided with a relatively smooth finish, as by machine lapping. Hard materials such as sapphire or tungsten can be employed.

To explain the manner in which my apparatus operates, it will .be presumed that the web of material is cellophane such as is employed for the manufacture of cellophane bags, or for the wrapping of boxes or other packages. The side margin of the web of material is placed between the anvils 2| and 22, in line with the path of movement of the markings IS. The spacing between the anvils is adjusted so that the anvil faces are substantially in contact with the opposite surfaces of the material. Preferably the spacing is slightly greater than the actual gauge thickness of the material. As previously mentioned by way of example, where the cellophane is 0.001 inch in thickness, the setting can be 0.00101. The material will now move freely between the anvils with a minimum of resistance. When a marking I9 commences to enter between the faces of the anvils, there is an immediate and substantial resistance to such movement, and this resistance causes the micrometer to be moved upwardly (Figure 3) to operate the contacts of the switch 36. The marking will however be moved between the faces of the anvils, without causing any permanent distortion or tearing of the material.

Irrespective of the theories which may be advanced to explain the effects obtained, the markings pass smoothly between the anvils upon application of a substantial increase pull, and the resistance to such movement is ample for operation of the electrical switch. I attribute this in part to the fact that cellophane, Pliofilm, and polyethylene? films possess peculiar characteristics which make them applicable to the present invention. Such materials are nonfibrous and they carry a high polish or glaze, whereby the coeflicient of friction normally offered when in contact with a polished metal surface, is relatively low. Such materials are likewise more or less stretchable or compressible, Whether because of the characteristics just mentioned, or characteristics of which I am not aware, the fact is that such materials appear to be particularly amenable to the present invention, and make possible reliable operation of electrical contacts by the use of my mechanism.

As is understood by those skilled in the art, various types of electrical circuits can be controlled by the electrical contacts. Figure 4 for example illustrates the contacts of the switch being employed to control a relay, which in turn controls certain automatic functions of the bag making or othermachine. Thus in this instance the contact 36a controls an energizing circuit l -i for the relay 45. Contacts 41 of this relay control a circuit 48, which can include a source of current, and a device such as an electrical solenoid. l he solenoid in turn can secure operation of a solenoid or some other part of the associated machine. The relay is shown provided with holding contacts 4'9, which are connected in series with the holding circuit 50-. This circuit can include the rearming or reset switch 5|, which is normally closed, and which is opened to break the holding circuit andthus permit the relay: to return to its original position. The switch 5| can likewise be operated by some part of the machine in order to recondition the circuit after a series of automatic operations. The relay 46 should preferably be of the slow-closing, quick-opening type, in order to provide a short time delay and thereby prevent false operation due to momentary false operation of the contacts 36a.

Another type of circuit is illustrated in Figure 5. In this instance an amplifier 52 has its input coupled to a circuit 53, which includes the contacts 36a. Circuit 53 also includes the battery or source of direct current 54, condenser 55, the leak resistance 56, and the inductive choke 51. The output of amplifier 52 is connected to the actuating winding of the relay 46. The function of the condenser 55 is to prevent false operation due to momentary closure of the contacts 353a, other than a closure properly caused by a marking upon the material. When the contacts 360, are closed only instantaneously, the voltage across condenser 55 does not have an opportunity to build up to such a value as to cause operation of the amplifier 52. However when the contacts 36 are closed for a substantial period of time, as by passing a marking between the two anvils of the micrometer, there is opportunity for sufficient voltage to develop across condenser 55 to impress a potential upon the input of amplifier 52, whereby this amplifier is operated to energize the relay 46.

It will be evident from the foregoing that my invention provides a relatively simple apparatus for application to Various machines which employ an extended web or strip of material like cellophane, Pliofilm, or polyethylene. The strip may move either continuously or intermittently, depending upon the automatic or semiautomatic cycling of the machine with which the invention is employed. While markings in the form of rectangular contoured areas can be used as illustrated in Figure 3, it is evident that other shapes of areas can be used, as for example a relatively narrow printed line, a triangle, or a circular area. It will be evident that the anvils need not be formed as a part of a micrometer. Thus they may be carried by a special mounting, with accurate means for adjusting the position of one anvil with respect to the other, and with adequate provision for maintaining the faces of the anvils in accurate parallelism.

I claim:

1. Electrical control apparatus for use with a movable web of material like cellophane, "Pliofilm or polyethylene, the web having ink markings printed thereon and spaced longitudinally of the web, a pair of spaced anvils disposed on opposite sides of the material in line with the path of movement of the markings, the faces of said anvils being parallel and substantially in contact with the adjacent side surfaces of the web, means for mounting said anvils and for holding the same in rigid relationship relative to each other, the spacing between said anvils ermitting relatively free movement of the web between the same but offering, substantial resistance to passage of the material plus the markings, means for supporting the mounting for limited movement of the same in a direction longitudinally of the web, and relatively movable electrical contacts operated by movements of said mounting.

2. Electrical control apparatus for use with a movable web of material like cellophane, Pli-ofilm or polyethylene, the web having ink markings printed thereon and spaced longitudinally of the web, a pair of spaced anvils disposed on opposite sides of the material in line with the path of movement of the markings, the faces of said anvils being in close parallel relationship and substantially in contact with the adjacent surfaces of the web, the spacing between said anvils permitting relatively free movement of the web between the same but offering substantial resistance to passage of said markings, means forming a mounting for said anvils and for holding the same in rigid relationship relative to each other, one of said anvils being adjustable on said mounting relative to the other anvil to adjust said spacing, means for supporting the mounting for limited movement of the same in a direction longitudinally of the web, and a pair of electrical contacts operated between open and closed positions by movements of said mounting.

3. Electrical control apparatus for use with a movable web of material like cellophane, Pliofilm or polyethylene, the web having markings printed thereon and spaced longitudinally of the web, a pair of relatively movable electrical contacts, and means for effecting closing and opening of said contacts responsive to the difference between the gauge thickness of the web and thickness of the material plus the thickness of the markings, said last means including a pair of opposed anvils disposed in relatively close apposition with the side surfaces of the web, means mounting said anvils for limited movement in a direction generally parallel to the direction of movement of the web between the anvils, said contacts being arranged to be opened and closed responsive to such movements, and means for yieldably urging the anvils in a direction opposite to the normal direction of movement of the web.

4. Electrical control apparatus for use with a movable web of material like cellophane, Pliofilm or polyethylene, the web having ink markings printed thereon and spaced longitudinally of the web, a pair of relatively movable electrical contacts, and means for effecting operation of said contacts, said last means comprising a pair of anvils having opposed parallel faces, said faces being disposed in close apposition with the side surfaces of the web, the normal spacing between said surfaces being less than the thickness of the web material plus the thickness of the ink markings, and mounting means supporting both said anvils for conjoint limited movement in a direction generally parallel to the direction of movement of the web between the anvils, said contacts being arranged to be opened and closed responsive to such movement.

5. Electrical control apparatus for use with a movable web of material like cellophane, Pliofilm or polyethylene, the web having ink markings printed thereon and spaced longitudinally of the web, a pair of spaced anvils disposed on opposite sides of the material in line with the path of movement of the markings, the faces of the anvils a i the mounting in a direction opposite to the normal direction of movement of the web.

RENE J. GAUBERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS m Number Name Date 1,792,979 Greenleaf et al Feb. 17, 1931 2,399,113 Guenther Apr. 23, 1946 2,419,518 Eichinger Apr. 22, 1947

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