US2561641A

US2561641A - Aligning means for belt conveyers

Info

Publication number: US2561641A
Application number: US746375A
Authority: US
Inventors: Thomson James
Original assignee: Mavor and Coulson Ltd
Current assignee: Mavor and Coulson Ltd
Priority date: 1945-04-16
Filing date: 1947-05-06
Publication date: 1951-07-24
Anticipated expiration: 1968-07-24

Description

July 24, 1951 gmm 2,561,641

ALIGNING MEANS FOR BELT GONVEYERS Filed May 6, 1947 2 Sheets-$heet l IIIIII II V, ////l/1lI,/ \I

FIG 31.

[NV-[W703 t/g/ms' 77/0/750/1 WWW July 24, 1951 J. THOMSON 2,561,641

ALIGNING MEANS FOR BELT CONVEYERS Filed May 6, 1947 2 Sheets-Sheet 2 Patented July 24, 1951 FFICE ALIGNING MEANS FOR BELT CONVEYERS I James Thomson, Glasgow, Scotland, assignor to Mavor & Coulson, Limited, Glasgow, Scotland l Application May 6, 1947, Serial No. 746,375

' In Great Britain April 16, 1945 6 Claims. (Cl. 198-202) r This invention refers to conveyors of the endless belt type, in which at least one run of the belt is carried by a series of idler rollers incorporated in training, or self-aligningunits supported by swivel mountings.

The invention is especially, although not ex- .c'lusively, applicable .to conveyors of the type stated in which the conveying run of the belt is troughed transversely by the use .of inclined idler rollers on which the belt is .carried. A usual arrangement is for-the idler rollers to be grouped in sets of three rollers, each set comprising a horizontal centralroller and an inclined outer roller at each side end-to-end with the central roller. There may of course be other numbers of rollers in a set to give the desired. trough effect. The main objector this invention is to provide an improved construction of belt-correcting means, the purpose of which is to return the belt to centralised running in the event that it should deviate to one or otherside and which acts, in case of need, in -two belt-correction stages, namely-a first stage action in which a minor corrective is. applied to thebelt when riding slightly out of centre; a second stage action in :WhiCh a major corrective, almost positive in its effect, is applied to the belt side.

Another object is to effect. a first-stage beltcorrecting action by adding a light but definite frictional drag to the belt at one side, by means .ofla normally inactive contact roller and, if necessary, to effect a second-stage. belt-correcting actionby applying a grip to the belt side by means of the contact roller, in which event the belt tugs the unit to swivel on its mounting.

The desired belt-centering function of the contact rollers canbe got by placing them to act on the belt in aplane that is perpendicular to the belt and contains the idler-roller axis or axes. same relationship to the belt inboth directions of running. g M

Training idler units as above described are located at intervals in thelength of the conveyor, the other. idlerdsetsbeing as usual of fixed construction and requiring no adjustment for reversal of the conveyor.

An example of training units accordingto the invention, as applied to a conveyor of thetype A contact device so placed exercises the statedywill now be described with reference to the.

accompanying drawings,;in which:

Fig. 1 isvan elevation of an upper belt-troughing unit and aulower returmrun unit,v and Fig. 2 is a side'elevationofthe units. Fig.3 is ,aplan of IVIV of Fig. 3, being drawn to a larger scale. Fig. 5 is a plan of a lower component of the base of either unit, on which base the idler brackets are mounted; and Fig. 6 is a section on the line VI-VI of Fig. 5 but showing upper and lower components of the base.

With reference firstly to the upper belt-troughing unit, this includes three belt-troughing idler rollers I, 8 and 9, which are journalled on brackets II) secured to an upper base plate II which is swivehmounted on a lower base plate I2 secured to the conveyor frame structure I3 (Fig. 1.) Each idler roller is borne by ball-bearings, one set of such bearings being shown at IDA in Fig. 4. The swivel-mounting is such that the rollers I to 9 and the base plate I I are free to swivel as a unit to a small extent about a vertical axis at the centre line of the conveyor. The swivel-mounting comprises a ball bearing I4 interposed between the two components II and I2 of the base. At each end of the upper base plate II a bracket I5 extends upwards past the outer end of the adjacent side roller I or 9 andcarries the contact device.

In the example, the contact device comprises a .small outside roller I6 which is in transverse alignment with the rollers I, 8 and 9, and whose axis is slightly inclined to the axis of the adjacent roller 1 or 9, and which extends inwards from the bracket I5 towards the outer end of the inclined roller. The contact roller I6 comprises a first part ISA, which is of the same size as each roller 1 and 9 and the inner end of which nearly touches the outer end of the adjacent side roller, and an enlarged flange-like second part I6B located at the outer end of the first part and of larger diameter. The inner face of this second part has a number of rounded projections IT on it. Each contact roller I6 is borne by a hollow journal I welded to the bracket I5, the arrangement being such that the diametral size of the relatively sliding surfaces of the roller I6 and journal IE0 is as large as practicable in proportion to the diametral size of the roller portion I6A, so that said surfaces impose on the roller a frictional drag which renders the roller noticeably resistant to rotation in comparison with the inclined idler rollers I and 9 on their antifrictional ballbearings.

In use of the unit, if the belt I8 runs to one side it rides on to the slightly upwardly inclined part [6A of the contact roller. Ordinarily, the

frictional resistance to rotation offered by the roller I6 should. be sufilcient to induce the unit thel -upper unit. Fig. 14. is asection on. the line to swivel on the lower base plate I2 into a beltcage-ring 24. tional 'function of preventing dirt from passing, into the ball bearing 14. When lubricant is forced into the bearing, some of it squeeezs outwardsbetween the ring 23 and the base components-Lil i} The extent to which the upper belt-troughing unit can swivel is limited by pins'lawhich extend into slots, one of which is shown in Fig. 5, being denoted by 20. The upper plate ll is maintained central in relation to the lower platel2--byythe body of a central pin 2| screwed into the upper plate ll. Lubricant is supplied by condliifiS'QZ' to the race of the ball bearing [4. A lubricantretaining ring 23 is interposed between the plia-t'esg 29 and 3B is similar to that of the plates H and I 2 of the upper units and the means provided for lubrication and sealing are also similar.

In the event that the return run [8A of the 5 conveyor should become displaced towards one side, it at first contacts the top surface of the contactor roller 26 at, that side, the frictional drag of the contactedQriollers tending to swivel the

rollers

25 and 26 and the plate 29 as a unit 1 "on the stationary base plate 30 and thus to impart a centralising action to the return run IBA. If the belt continues to become displaced further sidewise, it; eventually engages the enlarged flangelike outer part of the roller 26, said part 15 acting as a limit stop to the sidewise motion of I l and I2, said ring closely surrounding the usual The ring 23 performs the-addithe belt and ensuring that the requisite swivelling motion of the

unit

25, 26, 29 takes place.

It will be manifest that the surfaces of the rollers 26 contacted by the belt lie at points in atransverse plane Q -Q which containsthe axis ,of the v.roller 25 and .which is perpendicular to thelower run [8A of the belt. Thus, the belt central-i'sing action takes place irrespectively'of and I2, thus forming a seal and also carrying 2 away from the proximity of the ring 23 anydirt which might have reached there.

- As will be seen best in Figs. l8 (not shown in Fig. 3) should be displaced side- 'wise from its central setting, the contact rollers 2 and 3, if the belt will act on the belt at points along a transverse "plane which is indicated by the line P-P in Fig. 2 and of which the right-hand portion is represented by the section-line IV-IV in Fig. 3, said ,:plane beingperpendicular to the belt and the ;'H,XBS of the idler rollers I, 8 and 9 being con- .tained in said plane. It is by virtue of this arrangement that the-contact rollers exercise their .centralising function irrespectively of the direc- .;tion in which the belt is travelling forthetime being. v

1 Modifications may be madewithout departing from the scope of the invention. For instance, instead of having contact rollers slightly inclined .to the inclined troughing rollers I and 9, each ,contact roller may be coaxial with the adjacent .troughing roller and may have its inner portion [6A made with a slight outwardly divergent taper. 1 "In the foregoing description with reference to the drawings, the invention has been described ,only as applied to the upper unit which comprises -.the troughing idler rollers 'l, 8 and 9 that support the conveying run of the belt I8.- The in- ;vention is also applicable to units having rollers which support a flat conveyor, typical units of thi kind'being used in the conveyor herein described by way of example as applied to the lower return run of the belt I8. A lower unit is shown in Figs. 1 and 2.

Referring to Figs.,1 and 2, the lower run of :the conveyor is denoted by IBA. As shown, the .lower unit comprises a single horizontal idler roller 25 which supports the lower run I8A, maintaining the belt in flat form. The roller 25 is associated at opposite ends with contactor rollers .26 each of which has the same construction as, and is mounted on large-surface bearings similarly to, each of the contactor rollers is of the .upper units. The contact rollers 26 are arranged coaxial to the belt-supporting roller 25, the axle .21 of which is journalledin brackets 23 on the upper plate29 of a base including also a lower plate 3ll secured to the stationary side structure "3Lof the conveyor.

The construction and arrangement of the upper and lower ba e 19 68 the direction in whichthe belt .is .travelling for the time being. 1 ,It will be manifest that the invention provides a self-aligning endless-belt idler unit comprising one or more anti-friction rollers 25 or I, 8, and 9 and supported by an anti-friction swivel mounting. 29, 3B or ll, 12, with beltcorrecting end ,rollerassemblies each-comprising a bearing IBC, acontact roller i6 journalled on said bearing in sliding frictional engagement therewith, the contact' rollerjfi being arranged beyond an end of ,the unit so that in normal central running of the ,endless beltthe contact roller is stationary, being clear-of the belt 18, a roller surface IBA on the contactrollerwhichsurface is contacted by the underside. of. the belt 18 only if the belt rides sidewise,.and .whichinclines upwards relative to the unders-ideof the belt so as to be all the better .engaged thereby,.and an outer enlargement IBB on the contact rollen-havingrounded projections I! to'engage the upperside of thebelt if thebelt rides excessively sidewise, 1 0vv that the belt is gripped between said surface and projections and in effect imparts a succession of corrective tugs tothe unitafThat is to say, whenever the belt is fully displaced sidewise, its side is gripped between the surface. ISA of the now rotating contact roller 16 and that projection I! which; for the time being, is passing through the topmost position in which aprojection I1 is shown in Fig.5. In the continued. rotation of the contact roller i6,..the active" projection Has it follows its circular path must press deeper into the nearly straight belt side. Thus, because of the action of the .projection H, the belt will tug the entire unit .to swivel about its axis (pin 2|).

,Iclaim:

1. In a self-aligning endless-belt idler unit which in use is supportedby a swivel mounting, "a belt-correcting end roller assembly comprising a bearing supported on said unit, a contact roller journalled onsa'id bearing in frictionalen ag'ement the'rewithQsaid contact roller being arrangedbeyond an end of said unit so that in normal central running of the endless belt'the contact roller rests stationary beyond the belt, a roller surface on said contact roller which surface is contacted by the underside of the belt only ifthe belt rides sidewise, and an outer enlargement on said contact roller, having projectbelt is gripped between said surface and projecting means.

2. In a self-aligning endless-belt idler unit which comprises a support and several antifriction rollers arranged thereon to form a conveyor belt into trough formation and which in use is supported by an anti-friction swivel mounting, said rollers including two outer rollers each set at an inclination, a belt-correcting end roller assembly at each end of said unit, each assembly comprising a bearing which is mounted on said support and the axis of which is in the same transverse plane as the axes of said outer rollers, a contact roller journalled on said bearing in sliding frictional engagement therewith, said contact roller being arranged beyond an adjacent one of said outer rollers so that in normal central running of the trough-formed belt the contact roller rests stationary beyond the belt, a roller surface on said contact roller which surface is contacted by the underside of the belt only if the belt rides sidewise and which inclines upwards relative to the active surface of said adjacent outer roller and an outer enlargement on said contact roller having rounded projections to engage the upperside of the belt if the belt rides excessively sidewise, so that the belt is gripped between said roller surface and projections.

3. In a self-aligning endless-belt idler unit which comprises a support and several rollers arranged thereon to form a conveyor belt into trough formation and which in use is supported by a swivel mounting, said rollers including two outer rollers each set at an inclination, a beltcorrecting end roller assembly at each end of said unit, each asembly comprising a bearing which is mounted on said support and the axis of which is in the same transverse plane as the axes of said outer rollers, a contact roller journailed on said bearing in frictional engagement therewith, said contact roller being arranged beyond an adjacent one of said outer rollers so that in normal central running of the troughformed belt the contact roller rests stationary beyond the belt, a roller surface on said contact roller which surface is contacted by the underside of the belt only if the belt rides sidewise, and an outer enlargement on said contact roller having projecting means to engage the upperside of the belt if the belt rides excessively sidewise, so that the belt is gripped between said roller surface and projecting means.

4. In a self-aligning endless-belt idler unit which comprises a support and an anti-friction idler roller thereon and which in use is supported by an anti-friction swivel mounting, a belt-correcting end roller assembly at each end of said unit, each assembly comprising a bearing which is mounted on said support and the axis of which is in the same transverse plane as the axis of said idler roller, a contact roller journalled on said bearing in sliding frictional engagement therewith, said contact roller being arranged beyond an end of said idler roller so that in normal central running of the endless belt the contact roller rests stationary beyond the belt, a roller surface on said contact roller which surface is contacted by the underside of the belt only if the belt rides sidewise and which inclines upwards relative to the active surface of said idler roller, and an outer enlargement on said contact roller having rounded projections to engage the upper side of the belt if the belt rides excessively sidewise, so that the belt is gripped between said roller surface and projections.

5. In a self-aligning endless-belt idler unit which comprises a support and an idler roller thereon and which in use is supported by a swivel mounting, a belt-correcting end roller assembly at each end of said unit, each assembly comprising a bearing which is mounted on said support and the axis of which is in the same transverse plane as the axis of said idler roller, a contact roller journalled on said bearing in frictional engagement therewith, said contact roller being arranged beyond an end of said idler roller so that in normal central running of the endless belt the contact roller rests stationary beyond the belt, a roller surface on said contact roller which surface is contacted by the underside of the belt only if the belt rides sidewise, and an outer enlargement on said contact roller having projecting means to engage the upperside of the belt if the belt rides excessively sidewise, so that the belt is gripped between said roller surface and projecting means.

6. In a self-aligning endless-belt idler unit, including an anti-friction roller and a support by which the roller is carried and which in use is supported by an anti-friction swivel mounting, a belt-correcting end roller assembly comprising a bearing mounted on said support and arranged beyond an end of said anti-friction roller, a contact roller journalled on said bearing in sliding frictional engagement therewith so that in. normal central running of the endless belt the: contact roller rests stationary beyond the belt, a roller surface on said contact roller which surface is contacted by the underside of the belt only if the belt rides sidewise and which inclines upwards relative to said underside, and an outer enlargement on said contact roller having rounded projections to engage the upperside of the belt if the belt rides excessively sidewise so that the belt is gripped between said roller surface and projections.

JAMES THOMSON.

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

UNITED STATES PATENTS Number Name Date 1,572,555 Nelson Feb. 9, 1926 1,705,558 Cuddihy Mar, 19, 1929 2,012,089 Sayers Aug. 20, 1935 2,109,923 Lemmon Mar. 1, 1933