US2669334A - Flexible switch for roller conveyers - Google Patents

Description

Feb. 16, 1954 R. H. METZGAR FLEXIBLE SWITCH FOR ROLLER CONVEYERS 2 Sheets-Sheff(l l Filed Sept. 8, 1949 Feb. 16, 1954 R. H. METzGAR FLEXIBLE SWITCH FOR ROLLER CONVEYERS Filed Sept. 8, 1949 2 Sheets-Sheet 2 la Il,

Patented Feb. 16, 1954 FLEXIBLE SWITCHA FOR ROLLER'. CONVEYERS RobertEMetzgar, Grand Rapids, Mich.,.assignor to Metzgar Company, Incl,

Grand Rapids,

Michga corporation of Michigan Application September 8, 1949,` Serial No. 114,500

8` Claims. l.

In roller conveyors, conveyor switches are frequently desirable iny order to be able-to connect one conveyor line with either of two or moreother conveyor lines at will.` Thus someof the articles moving along the first conveyor may bepassed away in one directionV while others proceed in a different direction.

One of ythemost satisfactorytypes of conveyor switches has involved a iiexible principle, the shifting of the switch beingaccomplished in part by. a` relative movement of each roller in the switch mechanism with respect to the preceding roller. Thus for straightway delivery the rollers wouldalbe parallelwliile for delivery to one side ofthe samerollers would be arranged in a curve andi would be properlydisposed with their axes arranged radially about the' center of the curve.

The. present invention provides such a switch with-a moresimple structure than has heretofore for flexible. switchesl having the high dependabilityof the present switch.

Additionalobjects` and` advantages of the invention will be apparent from the following description and` from the drawings, in which:

Figure 1. is a view looking down on a switch chosen for illustration of' this invention.

Fig.. 2"is a side elevation ofthe switch .seen in Fig. 1..

Fig; 3 is a bottom view of the switch shown in Fig. 1, rollers being omitted forsimplicity.

Fig. 4. is a perspective view of the flexible blade which aligns the rollers.

Fig. 5 is a transverse vertical sectionalview taken approximately on the line 5-5` or Fig. 2.

Fig. 6"'is` a similar view takenapproximately on the"1ine6'-6fof Fig; 2.

Although the law requires afull and exact description of at least one form of the invention, such as that which follows, it is, of course, the

further "improvenientsg and the appended claims are intended to accomplish thisfpurpose by particularly pointin'gout the parts, improvements or combinations'in which the inventive concepts are found.

The invention'hasxbeen illustrated as embodied in -a switch for connecting conveyor A atwillwith conveyor'B or conveyor C. Ordinarily the conveyor would slope downwardly from left to right sothatarticles delivered at higher points on con:- veyor A would roll down conveyor A and roll onto conveyor B-*orconveyor C, depending on the positionoffthe switch; The switch is `operated merely by operating a lever H. The lever H shifts the various shifts-ble roll units l2 between the position shown in full lines in Fig. l and a position in which the end roller unit is approximately parallel with fixed roller i3.

The switch unit includes a base formed mainly OfhOriZUntalbeams It? and Il and bed plate I8. As seen best inFig. 5, the beams i6 and il are formed of inwardly facing channel members. In the illustrated switch the beam l is straight, while the beam il is curved. However, in athreeway switch, designed to connect to a third conveyor'by making a righthand curve, the beam I5 would be curved to the right as the beam il is curved to the left.

The plate lil` may be secured between the beams l5 and Il" in any desired manner. That at present preferred is to Weld spacer blocks 2! to the inner faces of the beams as shown and to weld the plate lto the inner faces of blocks 2|. This leaves openings 22 through which any debris from the traveling articles may drop in order to keep the bed I8 clear.

Although the beams I il and I7 may be supported in any suitable manner, it is preferred that they are welded to connector beams 23 which are provided with connector brackets 24 for coupling to similar brackets on the conveyors A, i3 and C. Likewise, connector beams 26 are provided for coupling with the opposite sides of conveyors B and C.

Fixedrollers |3,. 27 and 28 are carried by the various connector beams as illustrated, any conventional bearings being provided. The rollers 21 may conveniently be called receiving rollers and the rollers I 3` and 28 delivery rollers.

Theswitching roller units l2 are constructed as seenbestin Fig. 5. Thus each roller unit (two aligned rollers) is supported by a carriage or low U.shaped frame which may include a bottom channel piece 3l and the end channel pieces 33, each end channeI piece being welded to the bottom piece 3i. This carriage slides on plate i3. Extending between end pieces 322 is bolt 33. The bolt passes through the end pieces 32 and :also through spacer or Spanner tubes 3d, between which is positioned a flexible band 3S. Washers may `be provided between the tubes 3i and the band 36, and likewise between the tubes Si and the end pieces 32. The dimensions are such that the band 3651s tightly squeezed so that it is held rigidly perpendicular to the axis of the assembly. As seen best in Fig. l, the band 36* extends through all of the shiftable switch rollers. As a mattei' of fact, it also extends to the end roll unit 3l which,

though resembling the shiftable roll units 2, is bolted to the bed plate I8 as by bolts 38 seen in dotted lines in Fig. 2.

The roller unit 38 at switch series is provided with pins or bolts 39 extending through the bed plate I8 but loose enough to ride freely in slot 4I. A shift plate 42 is secured to the pins 39 below the bed plate I8 and is operated by shift lever II. Thus as end roller 38 is shifted between the two illustrated positions, its angularity is correspondingly changed as the pins 39 follow slot 4I. As this roll unit 38 shifts it shifts its end of the flexible band 36 accordingly and the band 36 in turn shifts the various intermediate roller units I2 so that these rollers assume a smooth curve, if the switch is to a deflected position. At the same time each roller is maintained in proper relative position with respect to the adjacent rollers.

' The shift lever II may be pivoted to bed plate I8 by a bolt 44, preferably located where the center lines of conveyors B and C meet. Shift plate 42 may be similarly secured to shift lever II by a bolt 48, or it may be welded to it, since slot 4I is concentric with bolt 44.

The shift lever II may be operated manually by handle 41 or by a powered device which may be remotely controlled. For example, the powered device could be a fluid cylinder or an electromagnetic device.

As the rollers reach either extreme position, the lower flange 49 of the end piece 32 passes under the upper flange of the main beams I6 and I'I, thus securely locking the roller units against excessive movement and ensuring that the proper curvature is assumed by the conveyor as a whole.

The beams I6 and I1 are preferably welded to the various end brackets 23 and 26, although the load is preferably transmitted mainly through the respective anges. Thus the upper ange I of beam I8 may rest on the lower flanges 52 of brackets 23. In practice a thin spacer is positioned between these flanges so that the flanges 49 of the roller units I2 can pass under the anges 5I quite easily.

It is often desirable to provide side guides along the outside of curves along the roller conveyors so that if the conveyed articles approach the curve at high speed they will be forced by the side guides to follow the curve. Without such side guides such speed might be enough to cause the articles to slide off the conveyor at the curve. In the case of a switch such as the present switch, the side guide for the curve cannot be in position all of the time because it would obstruct movement of the articles in the straight direction when desired. According to the present invention a side guide automatically shiftable with the switch is provided when desired.

The most practical Way of accomplishing this is to provide independent side guide segments on the successive roller units I2. A few such segments have been shown in Figs. 1 and 2 and a cross-section of one of them is shown in Fig. 5. Here it is seen that each of the side guide segments or units may comprise a horizontal bar 56 curved outwardly at its ends so that articles will not catch on the ends. These bars may be carried by legs or rods 51 welded to the bars 53 and butt-welded to the upper flange 58 of end piece 32. One such segment may thus be carried by each end piece 32 along the side of the switch which is the outside of the switch in the curved position. In case the switch is designed to curve both to right and left, one of the side guide units the shiftable end of thel may be secured to each end piece 32 of the shiftable roller units.

Probably anyone skilled in the art would have no trouble selecting suitable materials. For such aid as it might give, the following data found satisfactory commercially are noted.

The flexible band 33 has been formed of 1/8" wide band steel 1 to 11/4" wide, sometimes 11/2".

The bed plate I8 has been formed of 10 gauge hot rolled sheet steel for narrower conveyors (lll/2), but heavier stock to at least 1/4 plate is contemplated for wider conveyors.

2" channel steel stock has been used for the beams I6 and I'I, brackets 23, etc., end pieces 26 and bases 3|. Steel tube stock of O. D. and .032 Wall thickness has been found satisfactory for spacer tubes 34 with Fe tie bolts 33.

Experience indicates that slot 4I may not be a true arc, but in any event it will be cut to accommodate the movement which guide bolts 39 are found to follow in a particular design to provide a radial disposition of the associated roller unit 38.

With the present design of switch the two end roller units 31 and 38 are intended to be in parallel relation to the adjacent fixed rollers. Alternatively they could be made to assume the same angularity with respect to adjacent fixed rollers as is assumed between adjacent shiftable rollers. This could be accomplished by a special shaping of slot 4I and by permitting one or both ends of the roller unit 3l to slide a limited amount under the influence of flexible band 38.

Although wide rollers have been shown in the drawings, narrow rollers, more commonly called wheels, could be used instead. In that event the bearings for the wheels would be separated by a series of spacer or Spanner tubes, the flexible band 33 being clamped at the center within this series in much the same manner as is now illustrated. At present it is contemplated 4that in each roller unit I2 there would be a wheel at each end, a wheel adjacent the flexible band 36 and a wheel at an intermediate position 'on each side.

In the illustrated form of the invention the bearing units do not need to be spaced apart by the spanner tubes 34 because they are spaced apart by the roller cylinders or jackets with which the bearing wheels have a press fit.

The conveyor may be supported in any suitable manner. For example, cross braces 5B may be Welded to the brackets 23 and 26 to rest on the cross members of tripod supports.

Each conveyor section is preferably coupled to an adjacent conveyor section by means of upwardly extending pins El rigidly associated with one conveyor section and extending up into a socket or eye 62 of the adjacent conveyor section. This provides a firm coupling. In fact, it is even practical to placey two adjacent conveyor sections `at a slight angle/'with respect to one another by' using the coupling at only one side, this coupling nevertheless providing a rm relationship between the two conveyor sections.

Although the switch unit illustrated will connect with a conveyor extending away at 45 degrecs from the entrance conveyor, it is apparent that a fixed curved conveyor section could be connected to the switch to deliver to a conveyor extending away at any angle. It is particularly common to use a 45 degree curve to thus connect to a conveyor extending at degrees from the entrance conveyor. f Any suitable means may be provided for holdingthe switch in either position.v Forexample.,

operating lever Il may engage one or the other of latch lugs 66 (Fig. 3), being urged toward plate I8 by spring 67.

I claim:

with the relatively xed and controlled roller units, said band extending through the axes of the roller units at approximately a mid point in the length of each roller unit.

2. A ilexible conveyor including a relatively xed roller unit, a controlled roller unit, a plurailty of intermediate roller units between the two, and a flat Flexible band of stiiT resilient material connecting the intermediate roller units with each other and with the relatively xed and controlled roller units, said band extending through the axes of the roller units at approximately a mid point in the length of each roller unit, and each roller unit being secured to the band in perpendicular relation thereto.

3. A flexible conveyor including a relatively a controlled roller unit, a plurallty of intermediate roller units between the unit, each roller unit being secured to the band in perpendicular relation thereto, and a slab-like supporting surface on which said roller units, and through them the band, are slidably supported.

5. A flexible conveyor including a relatively xed roller unit, a controlled roller unit, a pluthe intermediate roller units, whereby the series of intermediate roller units is wrapped about the beam to form a conveyor corresponding to its curvature.

controlled roller unit, a pluroller units between the a flat flexible band of stiff resilient material connecting the intermediate roller units with each other and with the relatively fixed `and conroller unit being secured to the band in perpendicular relation thereto, and means for limiting the movement of the intermediate rollers in one direction to conform all of said shiftable rollers to a uniform curve whereby the curve is spread through the entire series of intermediate rollers.

'7. A flexible conveyor including a relatively xed roller unit, a controlled roller unit, a plurality of intermediate roller units between the two, a flat flexible band of stiff resilient mateunit, roller unit being secured to tlre band in perpendicular relation thereto, a slab-like supporting surface on which said roller units, and

roller unit approaches the beam.

8. A exible conveyor including a relatively and, through it, of as they are shifted.

ROBERT H. METZGAR.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Datei 1,206,305 Cowley Nov. 28, 1916 1,792,011 Haley et al Feb. 10, 1931 1,808,134 Gotthardt et al. June 2, 1931 1,819,972 Resch Aug. 18, 1931 2,105,922 Maltby Jan. 18, 1938 2,114,146 Klein et al Apr. 12, 1938 2,146,893 Gotthardt Feb. 14, 19139 2,384,959 Pearson Sept. 18, 1945

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