Description

BOGIE LOCK

Technical Field This patent disclosure relates generally to a locking device of industrial machines, in particular for road paving machines, and to a method for locking a bogie, in particular for locking a wheel of the bogie in a raised position.

Background

Industrial machines, such as road pavers, are generally used in road construction. Restrictions on load limits are not imposed when operating the machine in road construction areas. However, limits are imposed for public roads and must be adhered to when driving the machines on such roads. The maximal allowed load per axle may differ between countries, e.g. in Germany the maximum load per axle is below 12 tons, as of the year 2008. Modern road pavers may exceed this weight: weights of about 20 tons and more are not uncommon.

There are two major types of road pavers available, the first type may include a large wheel at the rear and at least one wheel at the front; the second type may include a crawler belt at the rear and wheels in the front. The crawler belt driven pavers have the advantage of being more stable on loose ground, but may be difficult to maneuver and relatively slow compared to a fully- wheeled pavers. Front wheels of pavers are generally transversely mounted and may also serve to steer the vehicle. The real wheels are typically larger than the front wheels and take the greater amount of a load during operation of the machine.

In order to relief the rear axle for the road paver, the front wheel of the bogie, in forward direction, may be provided with a mechanism to enable it to be lifted up in order to reduce the forces acting on the rear axle of the vehicle. This distribution of forces may be sufficient to allow the road paver to be driven on roads. Solutions based on the principle are known, for instance, from German application DE29920556U1 and, earlier still, from paver finisher BB670 by Bitelli S. p. A., Italy. In both cases the road pavers are provided with actuating mechanisms that act to reduce forces acting on the rear axle of the vehicle.

It is the objective of the current disclosure to provide a bogie lock which may be effectively used also in existing road pavers or similar vehicles, which may be efficiently actuated and which may provide a secure fastening for a wheel of a bogie in a raised position.

Brief Summary of the Invention

In a first aspect, the present disclosure describes a front bogie lock for an industrial machine, in particular a road paver or a similar vehicle, comprising a lock block having a first coupling portion connectable to an abutment surface and a second coupling portion connectable to a supporting element, wherein the abutment surface is moveable relative to the supporting element and the first and second coupling portions of the lock block have a shape adapted to restrict relative movement between the supporting element and the abutment surface. Restriction of the relative movement between the supporting element and the abutment surface may lock apart the supporting element and the abutment surface.

In a second aspect, the disclosure describes a bogie for a vehicle comprising the bogie lock of the first aspect.

In a third aspect, the disclosure describes a method of locking a bogie comprising the steps of rotating the bogie to raise a wheel of the bogie and inserting a bogie lock between a bogie frame and a supporting element to restrict relative movement between the bogie frame and the supporting element.

Brief Description of the Drawings

The foregoing and other features and advantages of the present disclosure will be more fully understood from the following description of various embodiments, when read together with the accompanying drawings, in which:

Fig. 1 is a partial side view of a bogie comprising an embodiment of a bogie lock in a latched position and a bogie in a locked position;

Fig. 2 is a side view of a second embodiment of the bogie lock;

Fig. 3 is an isometric view of the second embodiment of the bogie lock in an unlatched position;

Fig. 4 is an isometric view of a second embodiment of the bogie lock in a latched position;

Fig. 5 is a side view of a vehicle comprising a bogie prior to rotation to a locking position; Fig. 6 is a side view of a vehicle comprising a bogie rotated to a position for locking a bogie;

Fig. 7 is a side view of a vehicle comprising a bogie in locked position.

Detailed Description This disclosure generally relates to a bogie lock for road paving vehicles and to a method of locking a bogie in a position in which a wheel of the bogie may be locked in a raised position.

Fig. 1 illustrates an embodiment of a bogie lock 10 for a bogie 20 according to the present disclosure. Bogie 20 may be mounted to a support frame 27 of a vehicle. The bogie 20 may comprise, a bogie frame 21, a first wheel 25, shown in a dashed line, and a second wheel 29. Both the first wheel 25 and the second wheel 29 may be removably mounted to the bogie frame 21 and both the

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fϊrst wheel 25 and the second wheel 29 may be rotatable relative to the bogie frame 21.

Referring to Fig. 1, the first wheel 25 is shown in a raised position relative to support frame 27 such that the first wheel 25 does not contact level ground 30. With the first wheel 25 in the relative raised position, the bogie 20 may be locked in that position, hereinafter termed as the locked position. The second wheel 29 may maintain contact with the ground 30 in the locked position. The first wheel 25 may be lowered, relative to the support frame 27, to the ground 30 after the bogie 20 has been unlocked, such that on substantially level ground 30 both the first wheel 25 and the second wheel 29 may be in contact with the ground 30.

The bogie frame 21 may be substantially rectangular-shaped with a longitudinal axis. Bogie frame 21 may comprise a pivot 28. The pivot 28 may be located substantially in the centre of bogie frame 21, preferably on the longitudinal axis, and may connect bogie frame 21 to the support frame 27 in a pivotal arrangement and may permit the bogie 20 to rotate about pivot 28 relative to the support frame 27. Rotation of bogie 20 may be possible when bogie 20 is unlocked and such a rotation may not be possible when the bogie 20 is locked. The bogie frame 21 may further comprise an opening 24. The opening 24 may be positioned adjacent to or at an end of bogie frame 21, preferably along the longitudinal axis of the bogie frame 21. The opening 24 may be substantially elongated.

A supporting element 23 may have an end mounted to the support frame 27. As supporting element 23 may be connected to support frame 27, rotation of the bogie 20 about pivot 28 may be relative to the supporting element 23. Bogie 20 may rotate about pivot 28 within predetermined limits. The supporting element 23 may restrict further rotation of the bogie 20 through abutment between a surface of the supporting element 23 and a surface of the bogie frame 21, which may be formed an any suitable portion of the bogie frame

21 corresponding to the position of the supporting element 23 on the support frame 27.

To lock a bogie, a bogie lock 10 may be inserted between the surface of the supporting element 23 and the surface of the bogie frame 21 thereby restricting any relative movement between the supporting element 23 and the bogie frame 21.

Preferably, supporting frame 23 lies within opening 24. The opening 24 may be bound by abutment surface 22. Abutment surface 22 may comprise two opposite linear edges 33 and two opposite rounded edges 34. The rounded edges 34 may, preferably, lie transverse to the longitudinal axis of the bogie frame 21.

Supporting element 23 may be positioned on support frame 27 such that with the bogie frame 21 pivotally connected to the support frame 27, the free end of the supporting element 23 may extend through opening 24. Preferably, when both first wheel 25 and second wheel 29 may be contacting substantially level ground 30, supporting element 23 lies substantially in the centre of opening 24 along the longitudinal axis of the bogie frame 21.

Further rotation of the bogie 20 may be restricted by the abutment between abutment surface 22 of the opening 24 and the supporting element 23. Preferably, the abutment surface 22 may be an edge of opening 24. Bogie 20 may rotate about pivot 28 until the supporting element 23 abuts a linear edge 33, of abutment surface 22, on either side of the opening 24. Accordingly, to restrict relative movement between the supporting element 23 and the bogie frame 21, the bogie lock 10 is inserted between an edge of opening 24 and supporting element 23.

The supporting element 23 may be cylindrical. Preferably, the supporting element 23 may be a bogie frame stop, which may be normally used to limit vertical rotation of the bogie, relative to the ground, within predetermined angles.

Fig. 2 illustrates an embodiment of the bogie lock 10. Bogie lock 10 may comprise a lock block 11. The lock block 11 may be formed in any suitable shape to engage between the surface of the bogie frame 21, formed on any suitable portion thereof, and the surface supporting element 23. Preferably, the lock block 11 may be shaped to engage between an edge of opening 24 and supporting element 23.

Lock block 11 may comprise a first coupling portion 12 and a second coupling portion 13.

The first coupling portion 12 may be formed on a side of the lock block 11 and may have a shape adapted to couple to the abutment surface 22 of opening 24. Preferably, the first coupling portion has a convex arcuate shape to couple to an edge of the opening 24. The first coupling portion may couple to both a linear edge 33 and a rounded edge 34 of the opening 24 to lock the bogie 20. The second coupling portion 13 may be formed on the side of the lock block 11 opposite to the first coupling portion 12. The second coupling portion 13 may have a shape adapted to couple to the surface of the supporting element 23. In one embodiment, the second coupling portion 13 may have a concave arcuate shape to couple to a surface of the supporting element 23, formed as a cylinder, such that the second coupling portion 13 may couple and pivot about the supporting element 23. At one end of the lock block 11, the first coupling portion 12 and the second coupling portion 13 may meet to form a protrusion 16. At the opposite end, the lock block 11 may comprise an edge 26. Edge 26 may be linearly formed. The lock block 11 may further comprise an interior side 35 and an exterior side 36, both bound by the first coupling portion 12, second coupling portion 13 and edge 26. The interior side 35 faces the support frame 27 and the exterior side 36 faces a wheel upon engagement of the bogie lock 10 between the

surface of the bogie frame 21, formed on any suitable portion thereof, and the surface of the bogie frame 21.

The bogie lock 10 may further comprise a flange 14. The flange 14 may be connected to a segment of the first coupling portion 12. Flange 14 may comprise a flange end portion 17, an outer surface 18 and a flange edge 19. Flange 14 may further comprise a contact surface 37 which may be adjacent first coupling portion 12 and may face the same direction as exterior side 36.

Protrusion 16 of the lock block 11 may extend beyond flange end portion 17 such that the flange 14 extends from edge 26 for lock block 11, partway along first coupling portion 12, to the base of protrusion 16. Hence, a lead gap 38 may be present between the flange end portion 17 and the tip of protrusion 16.

Flange 14 may be connected along a segment of the first coupling portion 12 such that interior side 35 of the lock block 11 and a surface of flange 14 are substantially flush. Flange edge 19 may be level with edge 26 of lock block 11. The remaining segment of the first coupling portion 12 is available to couple to the edges 33, 34 of the opening 24. In an another embodiment, flange 14 may be mounted on to interior side 35 adjacent to first coupling portion 12. In this embodiment, whole of first coupling portion 12 may be available to couple to the edges 33, 34.

The bogie lock 10 may further comprise a handle 15 mounted to the exterior side 36 of lock block 11. Handle 15 may be formed in any suitable shape. Preferably, handle 15 may be 'L' shaped with one end mounted to the exterior side 36 and the free end laterally displaced from exterior side 36 and provide suitable means for easily inserting and rotating bogie lock 10.

Fig. 3 illustrates a bogie lock 10 in an unlatched position. In this position, bogie frame 21 may be rotated to raise first wheel 25 and further rotation may be restricted by the abutment between linear edge 33 of the

abutment surface 22 and supporting element 23. A bogie lock 10 may be inserted into opening 24 and coupled with the supporting element 23.

The second coupling portion 13 may be formed with a concave arcuate shape and may be coupled to supporting element 23 formed as a cylinder. The first coupling portion 12 may not be coupled to the abutment surface 22.

Fig. 4 illustrates a bogie lock 10 pivoted about pivot 28 into the latched position. In this position, relative movement between the bogie frame 21 and supporting element 23 is restricted by the bogie lock 10. The first coupling portion 12 may be coupled to the abutment surface 22. Preferably, the first coupling portion may be formed with a convex arcuate shape to couple to a linear edge 22 and a rounded edge 34 of the abutment surface 22. The first coupling portion 12 couples to the linear edge 33 opposite to the linear edge 33 that abuts support element 23. Protrusion 16 may slot into the lead gap 38 between curved surface of support element 23 and abutment surface 22 of opening 24. In the latched position of the bogie lock 10, flange 14 is position along bogie frame 21. Bogie lock 10 may not be withdrawn or may not fall off the bogie frame 21 when in the latched position as the contact surface 37 may abut the bogie frame 21 and thereby may restrict movement of the bogie lock 10 toward first wheel 25. With the bogie 20 in the locked position and first wheel 25 not in contact with ground 30, the bogie frame 21 presses against the bogie lock 10 such that factional forces may act between the first coupling portion 12 and abutment surface 22. The skilled person would realize that the bogie lock 12 may also be retained in the bogie frame 21 through the action of the frictional forces and that a flange 14 may not be required.

In one embodiment, the bogie lock 10 may further comprise a rib extending from interior side 35 for abutting support frame 27 thereby preventing movement of the bogie lock 10 toward support frame 27. The rib may optionally

extend from the support frame 27 and abut the interior side 35 upon insertion of bogie lock 10 into opening 24.

The steps of rotating the bogie 20 into the locking position are shown in Figs. 5 to 7. Referring to Fig. 5, both the first wheel 25 and the second wheel

29, of a vehicle 39 may contact the level ground 30 such as in a road construction area. A vehicle 39 may be kept even during operation as bogie 20 absorbs the effects of movement along an uneven ground 30 of a construction area. Hence, during movement along uneven ground, bogie 20 may rotate about the pivot 28 relative to support frame 27 thereby keeping the vehicle 39 even. With both wheels 25, 29 of the bogie in contact with ground 30, rear axle 32 carries a load which may be greater than official road limits. In order to reduce the load on the rear axle 32 to that the vehicle 39 may be driven on public roads, front wheels 25 of the bogie 20 may be locked in a raised position. Referring to Fig. 6, the vehicle 39 may be driven forwards onto an inclined ground 30 such that first wheel 25 may be raised with respect to the support frame 27 and bogie 20 may be rotated with respect to support frame 27. The vehicle 30 may also carry steel ramps or wheel chocks. The steel ramps or wheel chocks may be used to raise the first wheel 25, for instance in the event no inclined slopes are present in the road construction area or building site.

The supporting element 23 may abut abutment surface 22 of the opening 24 and may thereby restrict further rotation of the bogie 20. After the vehicle has been stopped in this position, a bogie lock 10 may be inserted into opening 24 and the second coupling portion 13 may be coupled to the supporting element 23.

Bogie lock 10 may then be rotated from the unlatched position into the latched position, and the first coupling portion 12 may thus be coupled to the abutment surface 22. The shape of the bogie lock may be such that when the

abutment surface 22, particularly linear edge 13, is in contact with supporting element 23, bogie lock 10 may fit into place.

Flange 14 may slide along bogie frame 21 and contact surface 37 may contact the bogie frame 21. Initial engagement of the flange 14 during coupling between the first coupling portion 12 and the abutment surface 22 may be assisted by lead gap 38.

In the latched position, lock block 11 may lock the supporting element 23 and the abutment surface 22 in place and may restrict relative movement between the supporting element 23 and the abutment surface 22, thereby locking the bogie.

Referring to Fig. 7 the vehicle 39 is now reversed from the incline. Bogie 20 is prevented from rotating back to a position parallel to the ground an even position by lock 10 and front wheel 25 is retained in the raised position. In such a locked position, the load on the rear axle 32 may be reduced and the load transmitted to ground 30 though wheel 31 may thus be lowered to below the prescribed limit. Hence vehicle 39 may be driven on public roads.

The material used for constituting parts of the bogie lock may be metals, like steel, iron or any other material having characteristics similar to such metals. In the drawings and in the above description, reference is made to a bogie lock 10 to be applied on the right hand side of a bogie 20. The person skilled in the art understands without any effort that the same description and drawings would apply to a bogie lock 10 for the left hand side of a bogie 20 and that, in a preferred embodiment, bogie locks 10 according to the disclosure should be used on both sides of the bogie 20.

Industrial Applicability

This disclosure describes a bogie lock 10 for locking a bogie 20 of a road paver. Locking a bogie 20 with a first wheel 25 in a raised position reduces the load carried by the rear axle 32 of the vehicle 39. Hence, a lower

load is transmitted to ground 30 through wheel 31. The vehicle 39 may be driven onto public roads with an axle limit below the official limits.

The industrial applicability of the bogie lock 10 for locking a bogie 20 as described herein will be readily appreciated from the foregoing discussion.

The present disclosure is applicable to a road paver, but not limited to other heavy-duty vehicles having the need to load balance the forces between front and rear axles to be able to be relocated on official streets. The bogie can be either a front bogie, as in the present description, a rear bogie or a bogie located in any other position.

Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein.

Where technical features mentioned in any claim are followed by reference signs, the references signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, neither the reference signs nor their absence have any limiting effect on the technical features as described above or on the scope of any claim elements.

One skilled in the art will realize the invention may be embodied in other specific forms without departing from the invention or essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting of the invention described herein. Scope of the invention is thus indicated by the appended claims, rather than the foregoing description, and all changes that come within the meaning and range of equivalence of the claims are therefore intended to be embraced therein.