US2720432A - Pivot centre for articulated locomotives - Google Patents

Description

Oct. 11, 1955 J. HADFIELD 2,720,432

PIVOT" CENTER FOR ARTICULATED LOCOMOTIVES Filed Oct. 2, 1950 4 Sheets-Sheet 1 Oct. 11, 1955 J. HADFIELD 2,720,432

PIVOT CENTER FOR ARTICULATED LOCOMOTIVES Filed Oct. 2, 1950 4 Sheets-Sheet 3 Oct. 11, 1955 HADFIELD 2,720,432

PIVOT CENTER FOR ARTICULATED LOCOMOTIVES Filed Oct. 2, 1950 4 Sheets-Sheet 4 f'fms, ll

lnven for W W ByJZ-MW S 215%.

A rneys United Sttes Patent dice 2,720,432 Patented Oct. 11, 1955 PIVOT CENTRE FOR ARTICULATED LOCOMOTIVES James Hadfield, Romiley, Chester, England Application October 2, 1950, Serial No. 187,891

14 Claims. (Cl. 308-437) This invention, an application which is a continuationin-part .of my copending U. S. application Ser. No. 783,991 filed November 4, 1947, now abandoned, relates to articulated locomotives and like vehicles, that is to say vehicles in which articulated or pivoted joints are used, and is concerned with the pivotal centre pieces or .pivot centres of such vehicles.

1 In articulated locomotives and like vehicles experience has shown that two major difiiculties arise in practice with the pivot centres; firstly, difliculties are experienced in taking up the slack caused by Wear of the pivotal centre pieces; and secondly, in providing the necessary means to permit tilting or angular movements in vertical planes to take place between the male and female members of the pivot centres.

In seeking to obviate the first of these difficulties it has previously been proposed to provide for the pivot centres renewable wearing blocks of the kind adjusted by wedges acting at right angles to the axes of the pivots. In practice it is found that in articulated locomotives and like vehicles such devices as are at present employed are diflicult to operate, in as much as they are usually of necessity located in positions which are diflicult of access, and moreover they require the assistance of external forces of considerable magnitude usually in the form of additional locomotive power with which to slide the male and female parts of the pivot centres relative to each other into the appropriate positions such as will enable the wedges to be adjusted in order to take up the slack.

In seeking to obviate the second difficulty it has previously been proposed to make provision for the tilting or angular movements in vertical planes between the male and female parts of the pivot centres by providing clearances between the mating parts when such parts are cylindrical in form or alternatively to make such partshemispherical in form. In the case of the cylindrical form of pivot the provision of the requisite clearance to permit the necessary tilting or vertical angular movements between the male and female parts of the pivot centres leads to considerable vibration and hammering action when the articulated locomotive or like vehicle is at Work, and consequential wear and damage is caused both to the pivot centres themselves and to other detail parts of the locomotives or like vehicles.

Moreover, in order tominimise the amount of clearance required to permit the tilting or vertical angular movements to take place it has previously been found necessary to severely limit the depth of the vertical mating faces of the male and female parts of the pivot centre.

In the case of the hemispherical form of pivot centre it frequently happens that there is not sufiicient space to accommodate the increased depth necessitated by this form of construction, and moreover the parts are ex pensive to manufacture and repair.

One object of the present invention is the provision of means for obviating the difiiculty in taking up the slack caused by wear of the pivotal centre pieces.

Another object is to provide improved and simple means to permit tilting or angular movements in vertical planes to take place between the male and female members, which means will be free from the objection as to vibrating and hammering, and will not involve undue expense or the occupation of undue space.

In order that the invention may be more readily understood, reference is hereby made to the accompanying drawings wherein:

Figure 1 is a vertical section showing one example of an articulation system constructed according to the invention;

Figure 2 is a vertical section on the line A-A of Figure 1;

Figure 3 is a sectional plan on the line B-B of Figure 1;

Figure 4 is a plan view of Figure 2;

Figures 5 and 6 are diagrams in elevation and plan of a modification; and

Figures 7 and 8 are sectional and elevational diagrams of a further modification;

Figure 9 is a view of an optional detail; and

Figure 10 is an enlarged view of the pivot centre.

Figure 11 is a similar view to Figure 10 illustrating a slight modification.

Referring to the drawings the type of vehicle to which the articulation system is applied is an articulated locomotive of the well known type in which three units are articulated together end to end, the centre unit being a boiler unit which comprises the boiler and the cab, and each end unit being an engine unit which includes cylinders and driving wheels. of the framework of the boiler unit, designated by the reference F1 overhanging part of the framework of oneof the engine units, designated by the reference F2, and the pivot centre which is the subject of the present invention serves to connect the said framework part F1 to the framework part F2 so as to permit of pivoting about a vertical axis, the pivotal connection also being such that the framework part F2 supports a downward thrust of the framework part F1, or, in other words, such that the engine unit supports a due proportion of the weight of the boiler unit. It will be understood that the pivot centres connecting the boiler unit to both engine units.

are similar, and that the pivot centres transmit the tractive and bulfer forces between the engine unit and the boiler unit.

The numeral 1 designates the metallic male member of the pivot centre, supported on the framework part F2, and 23 designates the metallic female member which embraces said male member and is constructed in two parts, one of which constitutes an adjustable wearing block 3, a gap 2a being left to permit the necessary movement to effect the required adjustment for wear. Said female member is carried by the framework part F1.

The adjustable block 3 is mounted in a casing memher 4 of said framework part F1 and its edge face 311 is inclined as shown. In a side extension 4a of the casing member 4 an adjustable wedge 5 is housed, this wedge 5 having an inclined face 5a corresponding to and in co-operative engagement with the inclined face 312 of the adjustable block 3. Wedge actuating rods 6 pass upwardly and loosely through holes in the wedge 5 and nuts or heads 6a are provided upon which the wedge 5 is supported, a flanged saddle-bracket 7 engaging the undersides of the heads 6a. These rods 6 pass through guided bearings 4b in bosses 4c in the diaphragm or platform 4d of the structural framework F1 and their upper extremities extend into guides 7a in plugs 7b The drawings show part.

2 mounted in the top wall of the framework. At positions intermediate their ends the rods 6 are screw threaded as indicated at 612 and nut-like devices 8 located between the bottoms of the plugs 7b and the bosses 4c upstanding from the diaphragm or platform 4d of the framework P1.

In the arrangement shown in Figures 1 to 4 the peripheries of these nut-like devices are shaped in the form of worm wheels and are meshed with actuating screws 9 keyed on to spindle 9a supported in bearings 10 in the structural framework F1 and in a bearing 11 in the wall of wing 42 extending from the framework. The outer extremity of the spindle 9a is provided with an operating wheel or handle 12 conveniently located for operation. -In operation rotation of this actuating screw 9 effects rotation of the nut-like devices 8, which coacting with the screw threads 6b cause axial movement of the wedge actuating rods 6 so that the wedge S can be caused to cooperate with the adjustable bearing block 3 and thus any desired adjustment to compensate for wear between the male and female members of the pivot centre can be effected at will.

It is to be understood that other forms of gearing for effecting synchronous actuation of the wedge actuating rods 6 can be adopted. For example in Figures 5 and 6 there is indicated a method where gear wheels 13 meshing with the toothed nut-like devices 8 are employed and operated by a hand wheel 14 and in Figures 7 and 8 an arrangement is indicated where the actuating screws 9 are replaced by bevel pinions 15 keyed on to spindle 9a, and meshing with bevel wheels 16 on the wedge actuating rods 6. It will be understood that in both these cases the rods 6 must have facility for axial movement and a power ratio factor which will render the manual operation effective to overcome the resistance to be met.

. It will be seen that, by the above mechanisms the adjustments can easily be made and maintained from positions which are freely accessible, and that a high mechanical advantage is provided sufficient to magnify a reasonable manual effort on the part of the operator into a force of sufficient magnitude to overcome the frictional resistance to sliding movement between the horizontal faces of the male and female parts of the pivot centre which arise from the vertical loads permanently carried on these faces irrespective of whether or not the articulated locomotive is at work.

The means to obtain this high mechanical advantage is such as to enable the required adjustments to be made with a minimum amount of effort on the part of the operator and without the assistance of the large external forces previously required when adjusting the pivot centres of articulated locomotives and said means ensures the maintenance of the wearing blocks securely in their adjusted position.

A supplement or alternative to these manually operable mechanisms is illustrated in Figure 9.

In this case compression springs 17 are interposed between the heads of the plugs 7b and the bosses 4c. If the springs are sufficiently strong to draw up the wedge automatically as wear Occurs no further provision for compensating for wear would be necessary but by providing the plugs 71) with screw threads engaging screw threads on the rods 6 positive adjustments can be effected from time to time if desired, by manually screwing said plugs '7 b so that they engage the bosses 40. Thus means are provided by which the wear is taken up automatically, and if for any reason the springs should fail the Wear can be taken up positively by manual operation.

As has been before indicated it is necessary to provide for tilting movements between the male and female members of the pivot centre. The method employed according to the present invention is shown particularly in Figure 10. The male member 1 is given the form of a truncated cone and the female member, consisting of the two parts 2 and 3 before described, is similarly coned. The dotted lines illustrate the action when the tilt is in one direction but it will be understood that similar conditions obtain in whatever direction relative to the axis tilting takes place. It will be seen that normally the tapered surfaces of said two members mate to provide for slipping pivotal movement of said members relative to each other about a vertical axis, and that tilting movement of said members relative to each other in vertical planes is permitted accompanied by partial withdrawal of said members relative to each other. When withdrawal occurs, the faces of said male and female bearing members which are normally in full contact with each other separate, and upon tilting of one of the bearing members relative to the other contact between the bearing faces is reestablished only at opposite ends of the male bearing member and on opposite sides respectively of the axis of the bearing members.

Instead of the cone of the male and female members having a straight line generatrix as in Figure 10 it may have a convexly curved generatrix as in Figure 11.

The diameter of the male member at the face which first enters the female member will, of course, in all cases be smaller than the diameter at its other face.

The foregoing construction has the advantages that freedom of movement between the male and female parts of the pivot centres is secured Without clearances and with consequent reduction in wear; an increase in the depth of bearing surface is practicable when compared with the usual cylindrical construction which also tends to reduce wear. The possibility of oil leaking away through clearance spaces without adequately lubricating the bearingsurfaces is completely eliminated.

A further advantage of the form of construction now proposed is that it permits the use of mating surfaces having greater depth of contact than was previously practicable with the cylindrical form of pivot.

It may be pointed out that the advantages of operating the wedge in a vertical direction, instead of, as heretofore, in a horizontal direction are, first, that it enables the manual adjusting element to be conveniently arranged at an accessible position. In addition it permits the provision of maximum bearing surfaces at all stages of adjustment to withstand the applied loading and said bearing surfaces are symmetrically disposed relative to the axis of the pivot members and support the adjusting blocks over the whole width thereof at all stages of adjustment.

It is to be understood that all the arrangements hereinbefore described are equally applicable to pivot centres of articulated locomotives and like vehicles irrespective of whether the male member is located above the female member or vice versa.

What I claim is:

1. Pivot centre for articulated locomotives comprising a rigid circular bearing support, a circular male bearing member having a circular bearing face mounted on said support, a fixed female bearing element having a substantially semi-circular inner face contacting with the face of the male bearing member, a laterally movable female bearing element having a substantially semi-circular inner face contacting with the male bearing member in opposed relation to and separated by a gap from the fixed female bearing element, the two elements constituting the female-bearing, the outer face on the movable bearing element being inclined to the vertical longitudinal axis of said male bearing member, a vertically adjustable wedge in co-operative contact with said inclined face, vertically disposed headed wedge adjusting rods passing loosely through holes in said wedge, the heads of said rods being in contact with the wedge, guides at the ends of the rods remote from the heads and means for causing the rods to move vertically with the wedge to effect lateral adjustment of the movable female element of the female bearing.

2. Pivot centre for articulated locomotives comprising a rigid circular bearing support, a circular male bearing member mounted on said support, a fixed female bearamass ing element having a substantially semi-circular inner face contacting with the male bearing member,'a later ally movable female bearing element having a'substantially semi-circular inner face contacting with the male bearing member in opposed relation to and separated by a gap from the fixed female bearing element,tl1e two elements constituting the female bearing, the outer face on the movable bearing element being inclined to the vertical longitudinal axis of said male bearing member, a vertically adjustable wedge in co-operative contact with said inclined face, vertically disposed headed wedge adjusting rods passing loosely through holes in said wedge, the heads of said rods being in contact with the wedge, guides at the ends of the rods remote from said heads, screw threads on said rods intermediate their ends, nut devices engaging said screw threads and means for simultaneously actuating said nut devices to effect vertical movement of said adjusting wedge to effect lateral adjustmerit of the movable female bearing element.

3. Pivot centre for articulated locomotives according to claim 2 wherein the nut devices are provided with peripheral teeth and are all simultaneously actuated by a common actuating device.

4. Pivot centre for articulated locomotives according to claim 2 wherein the nut devices are provided with peripheral teeth and are all simultaneously actuated by a screw threaded rod.

5. Pivot centre for articulated locomotives according to claim 1 wherein the male bearing member is in the form of a truncated cone and the female bearing is of corresponding contour.

6. Pivot centre according to claim 1 wherein the contacting faces of said male bearing member and female bearing are curved, the diameter of the male member at the face which first enters the female bearing being smaller than the diameter at its other face.

7. Pivot centre for articulated locomotives according to claim 1 wherein the wedge adjusting rods are actuated by springs.

8. Pivot centre for articulated locomotives, comprising a vertically disposed circular male bearing member, a. female bearing element having an arcuate inner face contacting with said male bearing member, a laterally adjustable female bearing element having an arcuate inner face contacting with said male bearing member in opposed relation to said first-named female bearing element and an outer face inclined to the vertical longitudinal axis of said male bearing member, the two female bearing elements constituting the female bearing, a vertically adjustable wedge in co-operative relation with said outer face on the adjustable female bearing element, vertically disposed headed wedge-adjusting pull rods passing through holes in said wedge with their heads engaging said wedge, and means for applying tension to said pull rods and thereby causing them to move vertically and thereby to pull said wedge vertically to effect lateral adjustment of the adjustable female bearing element.

9. Pivot centre for articulated locomotives, comprising a vertically disposed circular male bearing member, a female bearing element having an arcuate inner face contacting with said male bearing member, a laterally adjustable female bearing element having an arcuate inner face contacting with said male bearing member in opposed relation to said first-named female bearing element and an outer face inclined to the vertical longitudinal axis of said male bearing member, the two female bearing elements constituting the female bearing, a vertically adjustable wedge in co-operative relation with said outer face of said adjustable female bearing element, vertically disposed wedge-adjusting pull rods connected to said Wedge, and helical springs coiled on said rods and effecting a biasing pull on said rods and said wedge in the direction to adjust said adjustable female bearing element laterally against said male bearing member for taking up wear.

10.Pivot centre for articulated locomotives, comprising a vertically disposed circular male bearing member, a female bearing element having an arcuate inner face contacting with said male bearing member, a laterally adjustable female bearing element having an arcuate inner face contacting with said male bearing member in opposed relation to said first-named female bearing elem erit and an outer face inclined to the vertical longitudinal axis of said male bearing member, the two female bearing elements constituting the female bearing, a vertically adjustable wedge in cooperative relation with said outer face of said adjustable female bearing element, vertically disposed wedge-adjusting pull rods connected to said wedge, a structure supporting said adjustable female element against movement axially of the pivot relatively to said male member, nuts screwed on said pull rods, and helical springs coiled on said pull rods and in compression between said nuts and said structure and thereby effecting a biasing pull on said rods and said wedge in the direction to adjust said adjustable female bearing element laterally against said male bearing member for taking up wear.

11. Pivot centre for articulated locomotives, comprising a vertically disposed circular male bearing member, a female bearing element having an arcuate inner face contacting with said male bearing member, a laterally adjustable female bearing element having an arcuate inner face contacting with said male bearing member in opposed relation to said first-named female bearing element and an outer face inclined to the vertical longitudinal axis of said male bearing member, the two female bearing elements constituting the female bearing, a vertically adjustable wedge in co-operative relation with said outer face of said adjustable female bearing element, vertically disposed wedge-adjusting pull rods connected to said wedge, a structure supporting said adjustable female element against movement axially of the pivot relatively to said male member, nuts screwed on said pull rods, and helical springs coiled on said pull rods and in compression between said nuts and said structure and thereby effecting a biasing pull on said rods and said wedge in the direction to adjust said adjustable female bearing element laterally against said male bearing member for taking up wear, said nuts, when screwed on said rods in the direction to compress said springs, making contact with said structure and thereby positively adjusting said wedge in the direction to adjust said adjustable female bearing element laterally against said male bearing member.

12. Pivot centre for articulated locomotives comprising a vertically disposed circular, tapered male bearing member, a female bearing element having a complementary tapered arcuate inner face contacting with said male bearing member, a laterally adjustable female bearing element having a complementary tapered arcuate inner face contacting with said male bearing member in opposed relation to said first-named female bearing element and an inclined outer face, the two female bearing elements constituting the female bearing member, wedge means cooperative with said inclined outer face of said adjustable female bearing element, and spring means urging said wedge means in a direction to move said adjustable female bearing element laterally against said male bearing member for taking up Wear, said male and female bearing members being partially withdrawable from and tiltable relative to each other in vertical planes accompanied by separation of the normally fully contacting faces of said bearing members and reestablishing contact between the faces of said relatively tilted male and female bearing members only at opposite ends of said male bearing member and on opposite sides respectively of the axis of said bearing members.

13. A pivot centre as defined in claim 12 wherein said complementary tapered surfaces of said male and female bearing members have a straight line generatrix.

, 14. A pivot centre as defined in clairfflZ wherein said complementary tapered surfaces of said male and female bea ing members have a curved generatrix.

References Cited in the file of this patent UNITED STATES PATENTS 274,058 Tibbles Mar. 13, 1883 392,732 Hutchinson Nov, 13, 1888 446,296 Schoen Feb. 10. 1 91 10 2,258,640

8 Davidson Oct. 10, 18 93 Ra hbun --1 V 0C1. 8, 9,18 Pitkin w'J uly 23 1925. Volk 2 Feb, 27, 1934 Marti Oct. 1, 1935 Kjolseth Feb.'9, 19,37 Walton Sept. 7, 1937 Campion Jan. 17, 1939 Jackson Jan. 28, 1941 Beckette Oct. 14, 1941

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