GB1571530A - Self-propelled trolley for moving and guiding a torch for the automatic resurfacing of rails by in situ electric arcwelding - Google Patents

Description

(54) SELF-PROPELLED TROLLEY FOR MOVING AND GUIDING A TORCH FOR THE AUTOMATIC RESURFACING OF RAILS BY IN SITU ELEC TRIC ARC WELDING (71) We, LA SOUDURE ELECTRI QUE AUTOGENE, PROCEDES ARCOS, S.A., a Belgian Company, of Rue des Deux Gares 58-62, Bruxelles 7, Belgium, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to apparatus for automatic resurfacing, by electric arc welding, and particularly but not exclusively to a mobile apparatus which can be ued in a railwav yard. making it possible to resurface railwav rails "in situ" without any previous removal operations.

The majority of previously proposed mobile units for resurfacing or automatically welding horizontal joints comprise a chassis and propulsion and guiding means, of which the chassis is - either mounted on three or four wheels - or supported by external elements (e.g. rails or gantries) which are supported beyond the weld joint, and perhaps even bevond the pieces to be welded.

For example. patents such as British Patents Nos. 348331 and 1232288, German Auslegeschrift 1 146 6()3 and U.S. Patents Nos. 1 560 699 and 3 308 266 disclose welding units mounted on four wheel trol levs: and U.S. Patent No. 3 072 779 and British Patent No. 1 420 379 disclose support and guide elements, rails or other supports which are external of the joint, even external of the pieces; in contrast, U.S.

Patents Nos. 2 357 376 and 2 189 399 combine external supports and trolleys mounted on wheels.

In particular. when the work involved is resurfacing rails, the apparatus indicated above is generally of such a weight and bulk that it has to be supported on two rails, which makes it difficult to use in situ particularly on bends - even if the strength of a rail should prove adequate to withstand the weight of an automatic welding head, as is usually the case.

According to the invention, there is provided a self-propelled trolley carrying an arc welding torch and a drive unit for supplying welding wire to the torch, the trolley having wheels or rollers (herein called rollers) which are designed to support it on a metal rail which is to be re-surfaced by the use of the welding torch, the rollers being arranged in two groups spaced longitudinally with respect to the trolley of which one group is constituted by a pair of driven rollers each of which has a bevel chamfer and of which the other group includes either a single cylindrical roller or a pair of axially-spaced rollers having flanges to engage the outer side surfaces of the rail and which are slidably mounted on their axle so as to accommodate curves in the rail as the trolley moves along it in use.

In the case where the second group is a single roller, it may have a pair of flanges for engaging the sides of the rail.

A trolly according to a preferred version of the invention makes it possible to reduce in size (for example to 600 x 290 x 520 mm) and to lighten (e.g. by about 30 kg) the mobile welding assembly, so that it can be carried merely on the rail which is to be resurfaced, which means it can be used in situ and even in underground locations.

In this equipment, the heaviest elements comprising a welding current supply, and a control and operating panel having controls for welding current, rate of wire feed and trolley movement are fixed and dissociated from the lighter elements: whereas a motorreducer for supplying welding wire and an arc welding torch are grouped together on a self-propelled chassis; these latter elements being connected to the power source and the fixed remote control station by flexible cables which allow the trolley at least 10 metres free movement.

The equipment particularly disclosed and illustrated herein is characterised by a construction for guiding and supporting the self-propelled trolley on a single rail (which may have a recessed cross-section); this equipment comprises a rigid chassis carrying the mobile elements and resting on the rail through three or four rollers. The chassis and rollers have the following particular features.

The axial length of the chassis - constituting a chord when the rail is curved - is sufficiently small ( < 60 cm) to allow the trolley to run along a curved rail due either to the lateral slidability of a rear support roller or to the use of a cylindrical support roller, so preventing any derailing at normal rates of travel of the trolley (of the order of 1 m/min maximum).

The driven level-chamfered rollers can be symmetrical and can be mounted on the carrier axle facing outwardly or inwardly so that thev can be used in an internally rail-bearing or externally rail-bearing arrangement; also the level chamfering leaves adequate penetration clearance to compensate for normal wear and tear on the rail.

The attached drawings illustrate in greater detail trollevs based on two versions external rail-bearing and internal railbearing - of the apparatus according to the invention.

Figures 1, 1(a), l(b), l(c) relate to the external guidance version which is suitable for use on a rail with a recessed crosssection; fgitre I is a diagrammatic elevation of a mobile trolley resting on the single rail through two pairs of rollers.

Figure l(a) is a plan view of the trolley of Figure 1; Figure l(b) is a diagrammatic sectional view taken on the line I-I of Figure 1 looking from the left; Figure l(c) is a diagrammatic sectional view taken on the line II-II of Figure 1 looking from the right: and Figures 2, 2a. 2h and 2c show another embodiment of the invention.

The large arrow at the top of Figure 1 represents the direction of travel of trolley on the rail.

In these drawings, the reference numeral 1 represents an arc welding head (torch) capable of electric arc resurfacing of a rail, 2 represents the propulsion unit of the trolley, 3 represents the remainder of the light mobile elements associated with the torch, for example a welding wire supply reel and motor drive therefore, and 4 represents a chassis carrying the mobile elements and resting on a rail 5 through rollers A (A1/A2) and B (B1/B2).

As will become clearly evident from these drawings, the chassis (4) rests on two pairs of aligned rollers, the spacings between which are chosen so that the rollers rest on the rail head.

The driven guidance and front support pair of rollers are denoted Al, A2 and the rear support pair of rollers are shown at B I, B2; the guidance rollers Al A2 have bearing surfaces which have cut-off corners, that is to say, are bevel-chamfered. The rollers B1, B2 are loosely mounted on their axle with sufficient sliding clearance along the axle to absorb the curvature in the rail, if any.

Figures 2, 2(a), 2(b), 2(c) show an embodiment of the invention in which the rollers Al A2 bear on an interior surface of the rail.

In these Figures, Figure 2 is a diagrammatic side elevation of a self-propelled trolley resting on a single rail, supported by a pair of rollers Al, A2, a cylindrical roller B and a roller with bevel chamfered corners and serving as a rear guide roller: C.

Figure 2(a) is a plan view of the trolley; Figure 2(b) is a diagrammatic crosssection on the line I-I; and Figure 2(c) is a diagrammatic crosssection taken on the line Il-ll.

The large arrow at the top of Figure 2 shows the direction of movement of the trolley on the rail.

In Figures 2 to 2d, the alphabetical references - (A 1, A2) and numerical reference (1, 2, 3, 4, 5) have the same significance as in the previous drawings; furthermore the rollers of the second group include B which is an intermediate cylindrical bearer roller and C which is a rear guide roller which is in a single piece, mounted to pivot about a pivot pin e which connects it to the chassis.

As will be apparent from the drawings, the chassis 4 rests on a pair of driven bevel-chamfered rollers Al, A2; the spacing between the rollers resulting in their resting in the groove in the rail; the roller B keeps the chassis horizontal so that it can roll along the rail; guidance at the rear is provided by the roller C which is bevelchamfered. The roller C is capable of pivoting about a pivot pin e and is mounted on its axle with sufficient sliding clearance to absorb any curvature in the rail.

It should be noted: - that the guidance rollers Al and A2 in both versions are identical and therefore interchangeable, their spacing apart on the axle being regulable; - that the roller C may consist of two juxtaposed rollers Al and A2; - and that the roller B may consist of two rollers B1 and B2 fixed on a cylindrical boss.

The welding torch 1 is not shown in detail as it is conventional. It is mounted on the trolley by a clamping means which in a preferred version of the invention permits of a vertical adjustment of 60 mm, a lateral adjustment of 60 mm and a 1800 adjustment of its angle of inclination to the horizontal.

A prototype trolley has been constructed with a torch of 450 A (at 100%), fed with 3.2 mm wire; its total weight is 38 kg and its maximum dimensions are 600 x 290 x 520 mm. Its propulsion unit enables it to travel at the rate of 1 m/min maximum and the connections to a fixed power source and remote control station allow it 10 m autonomy, that is, 10 metres movement before it is necessary to move the power source and remote control station.

WHAT WE CLAIM IS: 1. A self-propelled trolley carrying an arc welding torch and a drive unit for supplying welding wire to the torch, the trolley having wheels or rollers (herein called rollers) which are designed to support it on a metal rail which is to be re-surfaced by the use of the welding torch, the rollers being arranged in two groups spaced longitudinally with respect to the trolley of which one group is constituted by a pair of driven rollers each of which has a bevel chamfer and of which the other group includes either a single cylindrical roller or a pair of axially-spaced rollers having flanges to engage the outer side surfaces of the rail and which are slidably mounted on their axle so as to accommodate curves in the rail as the trolley moves along it in use.

2. A trolley according to claim 1 in which the roller or rollers of the other group has or have a pair of flanges for engaging the sides of the rail.

3. A trolley according to claim 1 or 2 in which the other group includes a further roller mounted at the rear end on a mounting which is pivotably connected to the remainder of the trolley for pivotal movement about a horizontal axis.

4. A trolley according to claim 3 in which the further roller is freely mounted on a shaft which extends laterally of the trolley so that it is able to slide to a limited extent in the axial direction of the shaft.

5. A trolley according to claim 3 or 4 in which the said further roller has bevel chamfers for engaging the sides of the rail or the sides of a longitudinal groove in the rail.

6. A trolley according to any preceding claim including flexible cables for connecting it to a remote control station.

7. A trolley according to any one of claims 1-6 which includes a pair of frustoconical rollers at the front and a pair of flanged cylindrical supporting rollers at the rear.

8. A trolley according to any one of claims 1-6 which includes a pair of frustoconical rollers at the front, a cylindrical intermediate support roller and a bevel chamfered rear guide roller, the latter being designed to fit into a groove in the rail.

9. Equipment for the resurfacing of rails, by automatic arc welding, comprising: (a) a unit for the supply of welding current and a control and operating panel having controls for welding current, rate of wire feed and movement of the trolley, which unit can be fixed in position during use of the equipment; (b) a self-propelled trolley according to any preceding claim; and (c) connecting cables between the unit and the trolley.

10. A trolley substantially as hereinbefore described with reference to and as illustrated in Figures 1 and la to 1c of the accompanying drawings.

11. A trolley substantially as hereinbefore described with reference to and as illustrated in Figures 2 and 2a to 2c of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (11)

**WARNING** start of CLMS field may overlap end of DESC **. two rollers B1 and B2 fixed on a cylindrical boss. The welding torch 1 is not shown in detail as it is conventional. It is mounted on the trolley by a clamping means which in a preferred version of the invention permits of a vertical adjustment of 60 mm, a lateral adjustment of 60 mm and a 1800 adjustment of its angle of inclination to the horizontal. A prototype trolley has been constructed with a torch of 450 A (at 100%), fed with 3.2 mm wire; its total weight is 38 kg and its maximum dimensions are 600 x 290 x 520 mm. Its propulsion unit enables it to travel at the rate of 1 m/min maximum and the connections to a fixed power source and remote control station allow it 10 m autonomy, that is, 10 metres movement before it is necessary to move the power source and remote control station. WHAT WE CLAIM IS:

1. A self-propelled trolley carrying an arc welding torch and a drive unit for supplying welding wire to the torch, the trolley having wheels or rollers (herein called rollers) which are designed to support it on a metal rail which is to be re-surfaced by the use of the welding torch, the rollers being arranged in two groups spaced longitudinally with respect to the trolley of which one group is constituted by a pair of driven rollers each of which has a bevel chamfer and of which the other group includes either a single cylindrical roller or a pair of axially-spaced rollers having flanges to engage the outer side surfaces of the rail and which are slidably mounted on their axle so as to accommodate curves in the rail as the trolley moves along it in use.

2. A trolley according to claim 1 in which the roller or rollers of the other group has or have a pair of flanges for engaging the sides of the rail.

3. A trolley according to claim 1 or 2 in which the other group includes a further roller mounted at the rear end on a mounting which is pivotably connected to the remainder of the trolley for pivotal movement about a horizontal axis.

4. A trolley according to claim 3 in which the further roller is freely mounted on a shaft which extends laterally of the trolley so that it is able to slide to a limited extent in the axial direction of the shaft.

5. A trolley according to claim 3 or 4 in which the said further roller has bevel chamfers for engaging the sides of the rail or the sides of a longitudinal groove in the rail.

6. A trolley according to any preceding claim including flexible cables for connecting it to a remote control station.

7. A trolley according to any one of claims 1-6 which includes a pair of frustoconical rollers at the front and a pair of flanged cylindrical supporting rollers at the rear.

8. A trolley according to any one of claims 1-6 which includes a pair of frustoconical rollers at the front, a cylindrical intermediate support roller and a bevel chamfered rear guide roller, the latter being designed to fit into a groove in the rail.

9. Equipment for the resurfacing of rails, by automatic arc welding, comprising: (a) a unit for the supply of welding current and a control and operating panel having controls for welding current, rate of wire feed and movement of the trolley, which unit can be fixed in position during use of the equipment; (b) a self-propelled trolley according to any preceding claim; and (c) connecting cables between the unit and the trolley.

10. A trolley substantially as hereinbefore described with reference to and as illustrated in Figures 1 and la to 1c of the accompanying drawings.

11. A trolley substantially as hereinbefore described with reference to and as illustrated in Figures 2 and 2a to 2c of the accompanying drawings.