GB2176860A - Positioning toggle mechanism for railway sleepers - Google Patents

Abstract

A toggle mechanism has a two link system upper 1, with a pivot 7 at the upper end and lower link 2, an actuator 4 moving substantially perpendicularly to the upper link. The actuator is pivoted and constrained at its outer end in the vehicle chassis and at its inner end at the pivot point of upper and lower links, so that actuator extension causes the links to move in an arc about their common pivot, tending to increase the angle between them. A spring 3 assists this motion whilst keeping the lower rear edge of the lower link in contact with a roller 9 until both links are mutually abutted to prevent further hingeing, whereupon the mechanism moves only in an arc about the upper pivot of the upper link. Thus as the actuator is extended, the lower nose section of the lower link is caused to move firstly in a near vertical manner, approximately in line with the upper link, and after abutment of the links, to move in an arc about the upper link pivot substantially perpendicular to the line of the upper link. <IMAGE>

Description

SPECIFICATION Positioning toggle mechanism for sleeper or similar adjustment This invention relates to a toggle mechanism especially for moving railway sleepers and the like.

Toggle action mechanisms are well known and are often used to exert extremely high forces during the last stages of their movement. It is also known that in specific forms such a mechanism can be pivoted at one end so that the actuating means may generate forces in two directions, one substantially perpendicular to the actuators line of action, and one substantially in line with this action, but arcuately in respect of the pivot point.

According to the present invention there is provided a multiplicity of such toggle systems arranged in two pairs upon each of two lifting and mounting carriages, all carried within a main chassis of a wheeled vehicle, such a vehicle having power for self movement, for actuating various mechanisms, including the toggles and - its associated clamps (which resist the forces generated, to reposition the sleepers,) and for enabling additional tools to be used.

Such a vehicle and the mode of operation, and possible clamping forms are described in Patent entitled "Sleeper adjusting apparatus" under Application No. 8413638.

A specific embodiment of the invention will be described by way of example with reference to the accompanying drawings: Figure 1 shows in perspective the toggle mechanism, construction and the guide system.

Figure 2 shows a schematic side view of the toggle system mounted on its vehicle in the raised (transport) position.

Figure 3 shows a similar side view with the toggle system lowered into the working position. N.B. The left hand group are shown at the completion of their movements and the right hand group before commencing work.

Figure 4 shows a schematic plan view of the toggle and actuator systems as at Fig. 3 in relation to the sleepers and the rails.

Referring to the drawing Fig. 1 the toggle mechanism consists of a two armed upper link 1 (having an upper pivot 7, a lower knuckle pivot 8, an abutment 5 and spring anchor 6 formed integrally). A lower link 2 (having an extension 2a, a flat abutment face 2b and shaped nose section 2c formed integrally), an actuator 4, a closing spring 3, a guide roller 9 and a pair of guide rails 10. The lower link 2 mounted in a pivotable manner between the two arms of upper link 1 and the yoke 4a of the actuator on knuckle pivot 8.It can be seen that as the actuator 4 (in a preferred version, an hydraulic ram) extends, the spring 3 will cause the back edge of lower link 2 to remain in contact with the guide roller 9, thus imparting a near vertical (perpendicular to the rail) motion to the nose 2c of the lower link 2, thus permitting very high forces to be generated enabling the nose 2c to penetrate the possibly heavily compacted track ballast.

Further movement of the actuator 4 will cause (under the continued influence of the spring 3 and the constraint of the guide roller 9) the lower link 2 to partially rotate about the knuckle pivot 8 until the abutment face 2b of the lower link 2 comes into mutual contact with the abutment 5 of the upper link 1. At this stage the upper and lower links can no longer pivot in the direction as hitherto, and effectively become one link now moving in an arcuate motion about the upper link pivot 7.

From this it can be seen that such movement causes the nose 2c of the lower link 2 to be travelling in a near horizontal manner in order to push or pull (depending on direction of motion of the vehicle) the sleeper into its new position.

Referring to Fig. 2 the wheeled chassis 11 has a pair of slideably mounted carriages 12 having provision for the upper link pivots 7, the guide rollers 9 and guide rails 10 to be formed and carried within it, whilst having the ability to be raised and lowered upon its slides 13 by the actuator (in a preferred form, an hydraulic ram) 14. Such a raising and lowering ability permits the elements on the carriage 12 to be raised above the railway loading gauge line 15 for transport, and be lowered into a working position when the clamps (not shown) which are also slideably mounted (but spring 16 loaded upwards over a small distance) upon the carriage, to come into contact with and clamp the rail in order to commence working.Additionally the raising of the carriage 12 also allows a turntable (not shown) to be lowered to rail level and upon this the whole vehicle can be jacked up and rotated, for example, for changing tracks or loading on to another vehicle.

As on the vehicles are mounted eight toggle systems arranged in pairs it follows that by controlling the manner and sequence in which the actuators are energised several functions can be carried out. For example, if all four toggle systems on one side of the vehicle are operated then the sleeper will be moved si deways perpendicularly to the rail. If diago nally, opposite pairs of toggles are operated the sleeper can be twisted relative to the rail and so on. (Both examples are described as viewed in plan).

Referring to Fig. 3 the carriage 12 is shown lowered to the working position with the toggles on the right hand side of the illustration, retracted and about to commence work.

Movement of the actuator 4 progressively from 20 to 19 causes the nose 2c of lower link 2 to take up positions from above to enter the ballast as indicated by 1 8a and b until at 1 8c (pivot point 8 at 19) full penetrated is achieved and near horizontal motion may commence. On the left hand side of Fig.

3 the toggles are shown starting at this position of maximum vertical penetration and beginning sideways sleeper moving stroke "x" until actuator 4 stroke is exhausted at position 21.

It can also be seen from Fig. 3 that the nose 2c of the lower link is held well clear of the sleeper top surface 23 until the actuator 4 is extended. Various safety devices may be incorporated to prevent downward motion of the nose 2c if it should be positioned above an immovable obstruction such as sleeper 24 or other rigid construction.

Referring to Fig. 4 the drawing indicates how a sleeper can be moved in a manner or become parallel to an adjacent sleeper which itself is, or has been, adjusted to a datum.

The same figure also shows the disposition of the toggle mechanism 25 in relationship to the rails 26 and the vehicle centre line 27.

Claims (5)

1. A toggle mechanism for moving components relative to a fixed member which may form an anchor for the mechanism. The mechanism comprises a pair of upper links pivotally mounted at the upper ends within which at their lower ends is pivotally connected a lower link, spring based towards the upper link in a direction to put both links in line. This combination of links is further pivoted in the yoke of an extensable actuator whilst the lower link is caused to contact a roller, which when the actuator is extended will in turn cause the lower link to move in a direction substantially perpendicularly to the actuator movement. Further movement of the actuator will cause arcuate movement of the lower link substantially in line with the actuator extension.

2. A toggle mechanism largely as in Claim 1 wherein such a toggle can cause the lower link to move first substantially vertically, followed by substantially horizontal further movement.

3. A toggle mechanism largely as in Claim 1 wherein the device is protected from overload by, for example, sensors or probes (not described) which will detect the presence of an immovable object under the descending lower link nose.

4. A toggle mechanism largely as in Claim 1 where by adjustment of the link lengths and pivot and actuator positions, maximum "pene tration' and subsequent "moving" forces can be, generated.

5. A toggle mechanism with one end pivoted and the other guided to achieve the aims of Claim 4 in use to penetrate track ballast and move sleepers sideways without loosening their rail clips.