GB2116644A - Guide roller mounting - Google Patents

Abstract

A roller assembly including an axle 88 having projecting terminal portions provided with flats 90, 92 at the sides thereof adapted to pass through relatively narrow slots 96, 98 into circular mounting holes 100 where the axle can be turned crosswise to the slots by a laterally extending locking tab 102 on one of the terminal portions, the tab being manually bendable against a suitable part of the mounting structure to hold the axle normally securely in the mounting holes and being bendable away from such part to permit turning of the axle to align the terminal portions with and retraction thereof through said slots for servicing or replacement of the roller 50. The roller is a guide roller of a chain conveyor. <IMAGE>

Description

SPECIFICATION Guide roller mounting This invention relates two a guide roller mounting which, while it has general utility, is more especially adapted to be used for the guide rollers of work carriers in power and free conveyor systems of the type conventionally mounted overhead or under the floor in factories and other industrial environments where they are exposed to a great deal of dirt and grit that frequently penetrates to the wheel bearings and causes rapid wear and deterioration thereof. The location ofthese conveyor systems makes them difficult to service; however, if a proper service schedule is not maintained, the rollers that support and guide the work carriers throughoutthe system may frequently become so dirty and worn that they are immobilized.This, of course, greatly increases the resistance of the work carriers to movement by the power chain and correspondingly increases the load on the motorthatdrivesthe chain.

The carrier guide rollers are particularly subjectto wear and deterioration of the type noted above since the rollersturn on vertical axes and, although the bearings on which these rollers turn are sealed, the upwardlyfacing disposition ofthe bearings and the bearing races make them particularly vulnerable to penetration by dirt and grit As a result, these particular bearings require more frequent servicing.

The problem here is that there may be, and there usually are, thousands ofworkcarriers in a single conveyor system, and each work carrier is equipped with at least two guide rollers. Thus, considerable time is required to maintain the guide rollers properly in good operative condition. It is necessaryto shut down the conveyor system in order to service or replace the guide rollers, and conveyor downtime means loss offactory production which of course is extremely expensive. The way in which the guide rollers are normally mounted in the work carriers is, to a very considerable degree, reponsible for the time required to service or replace the rollers since the rollers are difficult to remove and replace.

The present invention provides a way of mounting the guide rollers in the work carrier bodies that holds the rollers securely in normal operation but which permits the rollers to be easily and quickly removed from the carrier bodies four inspection and greasing and, if necessary, replacement.

According to the invention there is provided a roller mounting for devices of the type having a body member provided with an open-ended recess in which said roller is mounted, said mounting comprising an axle for rotatably supporting and removable from said roller, said axle having a middle journal portion on which said roller is adapted to be rotatably mounted and terminal portions of similar elongate configuration in transverse section adapted to project in opposite directions beyond the sides of said roller, and means defining open-ended slots at opposite sides of said recess, said slots adapted to snugly but slidably receive the terminal portions of said shaft only when the major axes thereof are aligned therewith to permit movement of said terminal portions into and out of said slots, said slots having enlarged aligned portions remote from the open ends thereof in which the terminal portions of said axle can be turned crosswise of the slots to preventwithdraw- althereofwherebyto hold the same in said enlarged portions and to retain said roller in said recess, and a locking tab fixed to said axle forturning the same extending through and projecting from said recess, the projecting portion of said tab forming a handle for turning said axle and for slidably actuating said terminal portions into or out of said slots, said handle being deformable initiallyto interlock with said body to hold said axle in said crosswise position and subsequently to disengage said bodymemberto permit turning of said axle, retraction of said terminal portionsthrough said slots, and removal of said roller from said recess and said axle for servicing or replacement.

In the preferred exemplary embodiment the roller is a guide roller mounted on a vertical axle and having upwardly and downwardly extending terminal portions. Flats are formed on the projecting terminal portions of the axle at opposite sides thereof, and the axle is adapted for placement in mounting holes provided in the body by positioning the axle so that the flats align with open-ended slots extending radially from the mounting holes. These slots fit the terminal portions ofthe axle relatively snugly but with sufficient ciearance so that when properly aligned with the slots the axle portions pass readily therethrough and into the holes. Afterthe axle terminal portions have entered the holes, the axle is turned so that the flats are crosswise of the slots preferably by means of a tab which is mounted on and rotatably fixed to one ofthe terminal portions.In their crosswise position, the terminal portions of the axle are retained securely in the holes and the tab is positioned so that it can be bent to lie flat against a suitable seating surface provided on the body of the carrier.

When it is desired to remove the roller, it is simply necessary to bend the locking tab away from the seating surface of the body so that the tab can be readily grasped manually and turned to rotate the axie to a position where the flats again align with the slots. This permits the axle terminal portions to pass again through the slots and removal ofthe roller from the body. Thereafter, the roller can be easily and quickly lubricated or otherwise service or, if necessary, a new roller can be easily and quickly substi tutedforitandthe rollerand axle sub-assembly again remounted on the body in the manner hereinabove described.

The invention will be further described, by way of example, with reference to the accompanying drawings, wherein: Fig. 1 is an exploded perspective view showing a typical work carrier having front and rear guide rollers and particularly illustrating the manner in which the latter can be easily and quickly assembled with or disassembled from the body ofthe carrier according to the present invention; Fig. 2 is a plan view of one ofthe guide rollers shown in Fig. 1; Fig. 3 is an enlarged, vertical sectional view taken on the line 3-3 of Fig.2; Fig, 4 is an exploded, perspective view of the guide roller sub-assembly; Fig. 5 is a fragmentary, perspective view showing the manner in which the guide roller sub-assembly is positioned for assembly with the body of the work carrier;; Fig. 6 is a fragmentary, perspective view showing the guide roller sub-assembly in its initial assembled position on the body; Fig. 7 is a fragmentary, horizontal sectional view taken on the line 7-7 of Fig. 6; Fig. 8 is a fragmentary, perspective view similar to Fig. 6 but showing the guide roller sub-assembly in an intermediate assembled position; Fig. 9 is a fragmentary, horizontal sectional view taken on the line 9-9 of Fig. 8; Fig. is a fragmentary, perspective view showing the guide rollersub-assemblyin its final assembled position on the body; and Fig. 11 is a fragmentary, horizontal sectional view taken on the line 11-11 of 10.

The particularwork carrier shown by way of example in Fig. 1 comprises a body 20 which is formed from a pair of superimposed metal plates held securelytogether by bolts 22 and nuts 24. Work carriers ofthe type here shown are adapted to travel on the load track (not shown) comprising a pair of laterally spaced, inwardly facing parallel channels. To this end, the carrier body 20 is provided at the forward end thereof with a pairofload supporting wheels 26 mounted on an axle 28 that extends transversely through and projects laterally of the body adjacent the top and forward end thereof. A pair of rear wheels 30 is similarly mounted on the body 20 adjacent the rearward end ofthe latter and in horizontal alignment with the frontwheels 26.Only one rearwheel 30 is here shown but it will be readily appreciated that a pairofrearwheelsdisposed at opposite sides ofthe carrier body 20 are provided. In practice, the front and rear pairs of wheels 26 and 30 travel on the inwardly extending lowerflanges of the load track channels with the carrier body 20 disposed between the flanges.

Mounting brackets 32 bolted or otherwise secured to the lower portion ofthe carrier body 20 carry hangers to which workpieces orworkcarrying platforms (not shown) can be attached. In this connection, while only one mounting bracket 32 is shown inthedrawing, itwill be readily appreciated that a mounting bracket is provided at each side of the carrier body 20 andthatthe hanger conventionally is attached to both brackets and suspended below and atthe middle ofthe body to balance the load on the supporting wheels 26 and 30.

A drive dog 34 is attached by a pivot 36 between two laterally spaced upstanding brackets 38 and 40 at the frontofthe carrier body 20, and a hold-back dog 42 is fastened by a pivot 44 to laterally spaced upstanding lugs 46 and 48 on and at the rear ofthe body. In use, a pusher member depending from a drive chain (not shown) above and parallel to the load track extends downwardly between the drive and hold-back dogs 34 and 42, according to conventional practice. The chain pusher normally engages the drive dog 34to advance the work carrier to the left, as viewed in Fig. 1 ofthe drawing.However, on occasion, as when the work carrier is traversing a decline in the conveyor system, the carrier may tend to run aheadofthechain pusherand on these occasions the hold-back dog 42 engages the chain pusherto prevent the carrierfrom overriding the pusher.

Front and rearguide rollers 50 and 52 are mounted for rotation about vertical axes in open-ended horizontal recesses 53 and 54 provided in the front and rear, respectively, of the carrier body 20 below the load carrying wheels 26 and 30. Both rollers extend laterally beyond the sides of the body so as to engage the confronting free edges of the lower channel flanges on which the load carrying wheels 26 and 30 travel to hold the work carrier centered between the channels and to guide the carrier around horizontal bends of curves in the load track.

U.S. Patent No.3,033,128 issued May 8, 1962 to Adolph Czarnecki and assigned to the same assignee as the present application shows a work carrier of the same general type and construction as the one disclosed in this application, andthe disclosure of this patent is incorporated by reference herein for a more complete description and understanding of the work carrier and its association with the power and load tracks of an overhead, power-and-free conveyor system.

As suggested, the present invention is concerned particularly with the construction and mounting of the guide rollers 50 and 52. It is contemplated that both ofthese rollers be identical in construction and thatthey be similarly mounted and detachably fastened to the carrier body 20 so that a detailed description of one will suffice. Figure 1 is an exploded perspective view showing the front guide roller 50 and its mounting parts disassociated from the body 20, andthefollowing detailed description applies to that particular guide roller with the understanding that the rear guide roller 52 is similarly mounted.

Figs. 2 and 3 show a typical guide roller construction in which the outer roller body 55 is provided with a central opening 56 which is shaped adjacent the middlethereofto definetwo oppositely facing ball races 57 and 58. Mounted in the central opening 56 and spaced radially inwardly from the races 57 and 58 are superimposed inner annular race members 60 and 62 that are supported and retained in coaxial relation to the outer roller body 55 by an inner sleeve 64 and radial flanges 66 and 68 on the ends of the latter. Inner races 70 and 72 formed in the peripheries of the inner race members 60 and 62 are disposed generally in radial alignment with the outer races 57 and 58, respectively, and cooperate with the latter to support annular series of ball bearings 74and 76. In use, the outer roller body 55 rotates around the inner race members 60 and 62 traveling on and supported by the ball bearings 74 and 76.

As indicated previously, the work carrierfrequently and perhaps usually operates in a dirty environment in which both the load carrying wheels 28 and 30 and the guide rollers 50 and 52 become covered with dirt and grit. In many situations as, for example, where the conveyor system is in a foundry or the like, the dirt and grit is particularly heavy and abrasive. Invariably this dirt and grit penetrates the protective shields with which the load supporting wheels 26 and 30 and the guide rollers 50 and 52 conventionally are equipped so that it eventually packs between and around the ball bearings 74 and 76 causing excessive wear and sometimes "freezing" the bearing so that the rollers 50 no longerturn butsimply slide or skid aong the load track.In order to maintain the conveyor system in proper operating condition, it is necessary to keep all ofthe load carrying wheels and the roller bearings properly lubricated and to thoroughly clean or replaceanywheel or rollerin which the dirtandgrit has become so impacted so as to prevent free rotation thereof. In this connection, it will be readily apparentthattheguide rollers are particularly vulnerable to penetration by dirt and grit since they are mounted with one side thereof facing upwardly.

Although it is conventional practice to equip the guide rollers with inner and outer bearing retainers 78 and 80 as well as intermediate barriers82,84 and 86 of teflon, felt and teflon, respectively, the rollers still are subjectto failure in use in the mannerandforthe reason previously described.

The present invention is concerned particularly with a mounting for each of the guide rollers 50 and 52 which permits the rollerto be easily and quickly removed from the carrier body 20 for lubrication or other maintenance or, if necessary, for replacement.

The mounting of this invention holds the associated guide roller attached securely to the housing 20 during normal operation of the conveyor system and until removal for servicing or replacement is necessary; but, when the guide roller hasto be removed, it can be removed for servicing or replacement and reattached to the carrier body very quickly so as to minimize down-timeforthe conveyor.

Each guide roller is mounted on an axle 88 having flats 90 and 92 on opposite sides thereof. The axle 88 extends through a correspondingly shaped hole 94 in the inner race member 64. The terminal end portions of the axle 88 extend above and below the guide roller 50 as viewed in the drawings and the projecting terminal portions fit snugly but slidably in openended, vertical slots 96 and 98 that, in the case ofthe front guide roller 50, open through and extend rearwardlyfrom the forward edge ofthe carrier body 20 andtheyalso open into the recess 53 in which the rolleris normally mounted.Aswill beapparent,the projecting terminal portions ofthe axle 88 are inserted into the slots 96 and 98 with the flats 90 and 92 atthe sides of the slots so that the axle can move through the latter into circular holes 100 at the inner ends ofthe slots and at substantially the middle of the recess 53. When the axle terminal portions have been pushed into the holes 100, the axle 88 is turned 90" so that the flats 90 and 92 are disposed crosswise of the slots 96 and 98. In this position, the axle 88 can no longer enterthe slots 96 and 98 but is retained in the circular holes 100.

In orderto permit the axle 88 to be turned easily after it has entered the holes 100 and to assure secure retention thereof after it has been turned crosswise of the slots 96 and 98, a locking tab 102 is provided on the lower projecting portion ofthe axle, as clearly shown in the drawings. The locking tab 102 has an opening l04ofthesamecross-sectional shape and only slightly larger in sizethan the axle 88 sothatthe tab and the axle are rotatably interlocked and turn together.

In practice, the locking tab 102 is placed on the projecting lower end portion of the axle 88 at the underside of the guide roller 50 and,when the axle is inserted into the slots 96 and 98 as previously described, the tab extends laterally from the side of the carrier body 20 between the roller and the lower side ofthe recess 53. Figures 6 and 7 show the position ofthe partsatthistime.Afterthe axle88 has been fully inserted to the position described above, the tab 102 is turned 90" in aforward direction to the position shown in Figs. 8 and 9.This of course, turns the axle 88 also 90 , as previously described, so that the axle is positioned crosswise ofthe slots 96 and 98 and is retained inthecircularholes 100. Itis contemplated that the locking tab 102 be made of a low tempered, readily deformable metal so that it can be bent easily downwardly and that the carrier body 20 be provided with a vertical face 106 below and at the outer end of the recess 53 against which the tab is bent, as shown in Figs. 10 and 11. The flat seating engagement between the downwardly bent portion ofthetab 102 and the carrier body surface 106 holds the axle 88 crosswise in the holes 100 and prevents the axle from moving outwardly in the slots 96 and 98 in the normal operation of the work carrier. On the other hand, the tab 102 can be readily bent upwardly again to the position shown in Figs. 8 and 9 to permit turning ofthe axle 88 into alignmentwith the slots 96 and 98 and removal of the roller 50 from the body 20 for replacement or servicing .

Claims (10)

1. A rollermounting fordevicesofthetype having a body member provided with an open-ended recess in which said roller is mounted, said mounting comprising an axle for rotatably supporting and removable from said roller, said axle having a middle journal portion on which said roller is adapted to be rotatably mounted and terminal portions of similar elongate configuration in transverse section adapted to project in opposite directions beyond the sides of said roller, and means defining open-ended slots at opposite sides of said recess, said slots adapted to snuglybutslidablyreceivetheterminal portions of said shaft only when the major axes thereof are aligned therewith to permit movement of said terminal portions into and out of said slots, said slots having enlarged aligned portions remote from the open ends thereof in which the terminal portions of said axle can be turned crosswise of the slots to prevent withdrawal thereof whereby to hold the same in said enlarged portions and to retain said roller in said recess, and a locking tab fixed to said axle for turning the same extending through and projecting from said recess, the projecting portion of said tab forming a handleforturning said axle and forslidably actuating said terminal portions into or out of said slots, said handle being deformable initially to interlock with said body to hold said axle in said crosswise position and subsequentlyto disengage said body member to permit turning of said axle, retraction of said terminal portions through said slots, and removal of said rollerfrom said recess and said axle for servicing or replacement.

2. A roller mounting according to claim 1,wherein said roller has inner and outer race members and said axle hasthesame elongate configuration in transverse section throughout its length.

3. A roller mounting according to claim 2, wherein the inner race of said roller has an axle receiving opening having the same cross-sectional configuration as said axle.

4. Arollermounting accordingtoclaim 20r3, wherein said locking tab has an axle receiving opening having the same cross-sectional configuration as said axle for rotatably interconnecting said axle and said tab.

5. Arollermounting according to any preceding claim,wherein said locking tab is readily manually bendable.

6. A roller mounting according to claim 5, wherein said tab is of a material that is readily manually bendable and that maintains the shape to which it is bent to facilitate interlocking engagement between the tab and said body member and disengagement of said body member by said tab.

7. A roller mounting according to any preceding claim,wherein said body member is part of a work carrier assembly of a type conventionally used in overhead power-and-free conveyor systems, said roller extends beyond the sides of said body member for rolling engagement with load track sections on which said carrier is adapted to travel, and said body is provided atthe open end of said one of said slots with a seating surface against which the projecting portion of said locking tab is adapted to be bent and with which the bent portion of said tab cooperates to hold said axle with the terminal portions thereof crosswise of said slots.

8. A roller mounting constructed and arranged to operate substantially as herein described with refer ence to and as illustrated in the accompanying drawings.

9. Aconveyor carriage embodying a guide roller mounting as claimed in any preceding claim.

10. Aconveyorsystem including carriages as claimed in claim 9.