Steering mechanism for transport equipment

A steering mechanism intended for use in transport equipment, such as a truck, or a trailer, includes a steering knuckle on both sides of a body of the transport equipment. A king pin is fastened by articulation to the steering knuckles and a wheel of the transport equipment is fastened to each king pins. the steering knuckles being fastened by articulation to the body. The king pins are pivotable with respect to the steering knuckle to which they are fastened. The steering knuckles are pivotable so that when either of the steering knuckles pivots about the respective articulation arranged in the body, the king pin in the pivoting knuckle simultaneously remains un-pivoted with respect to the steering knuckle to which it is fastened. The other steering knuckle simultaneously remains un-pivoted and the king pin therein thus pivots with respect to the steering knuckle to which it is fastened.

RELATED APPLICATION DATA

This application is a §371 National Stage Application of PCT International Application No. PCT/FI2014/050049 filed Jan. 22, 2014.

FIELD OF THE INVENTION

The invention relates to a steering mechanism for transport equipment, which steering mechanism can be used, for example, in a truck or in a trailer of a truck.

BACKGROUND OF THE INVENTION

In transport equipment, such as for example trucks or their trailers, various steering mechanisms are used for enabling their steering.

One steering solution for transport equipment is presented in publication FI20105178.

The publication presents a transport equipment body provided with a plurality of wheels, of which at least one is a drive wheel, and a transport equipment centre articulation which divides the body of the transport equipment into a front body part and a rear body part such that the transport equipment further comprises a trailer connectable to the body of the transport equipment by a fastening articulation. Furthermore, a trailer comprises a trailer body, a trailer transport box, and a plurality of wheels, of which at least two wheels are arranged to be steerable wheels.

Another steering mechanism for transport equipment is presented in publication EP0700821. The publication presents a solution, in which the steering of the transport equipment (tractor) is implemented so that the front body of the transport equipment is provided with a steerable axle, pivotable hub pieces comprising a steering knuckle are arranged at the end of the axle, and the wheels of the transport equipment are fitted in the hub pieces.

The solutions of prior art involve the problem that a considerable amount of space is required for turning the wheels of the transport equipment, particularly if the wheels are large, and little space is thus available for the body structures between the wheels. On the other hand, it is not desirable to make the body structures larger/wider, because if the body structures, such as the chassis/chassis structures of the transport equipment, are made e.g. wider, the transport equipment no longer fits for use in limited spaces (such as, for example, mines).

Therefore, the transport equipment should be designed such that it can conveniently move and turn in relatively narrow and even limited spaces.

For examples in mines and underground as well as surface excavation, there is a clear need and demand for novel steering mechanisms for transport equipment which can be used to reduce the space required for turning without having to significantly modify the body structures in order to increase the turning radii of the wheels.

BRIEF SUMMARY OF THE INVENTION

It is an aim of the present invention to provide a novel steering mechanism in order to avoid the problems and drawbacks present in the state of the art.

The steering mechanism according to the invention is characterized in that the steering knuckles in the steering mechanism are fastened by articulation to the body of the transport equipment, and that hub pieces fastened by articulation to the steering knuckles are pivotable with respect to the steering knuckle to which they are fastened, and that the hub pieces are pivotable by means of actuators connected to them, and further that the steering knuckles are pivotable by actuators arranged in them to a desired angle so that for steering the transport equipment when either of the steering knuckles pivots about the respective articulation provided in the body, the hub piece in the pivoting steering knuckle simultaneously remains unpivoted with respect to the steering knuckle to which it is fastened by articulation, wherein simultaneously the other steering knuckle remains unpivoted in its articulation provided in the body, and the hub piece therein thus pivots with respect to the steering knuckle to which it is fastened by articulation.

An improved solution for a steering mechanism for transport equipment is now provided. Some preferred embodiments of the invention are disclosed in the dependent claims.

The present invention provides several advantages, which become more apparent in the detailed description.

By the steering mechanism according to the invention, in spite of the large turning angle of the wheels, space for the body is amply provided between the wheels; in other words, even if the turning angles of the wheels may be large, the wheels still do not require a lot of space. For this reason, there is no need to make the body structures larger (in other words, to modify the body structure in order to make the turning angle of the wheels larger) for increasing the turning angles of the wheels.

DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION WITH REFERENCE TO THE DRAWINGS

FIG. 1ashows the steering mechanism according to the invention in a perspective view, and in a corresponding manner,FIG. 1bshows the steering mechanism according to the invention in a top view, the steering mechanism being arranged in the body of the transport equipment.FIGS. 1aand 1billustrate a situation in which the transport equipment is driven straight ahead, but it is obvious that the steering mechanism also works in a situation of reversing, that is, when the travel direction of the transport equipment is initially opposite to that shown by an arrow inFIG. 1a.

As seen inFIG. 1a, the steering mechanism according to the invention, particularly intended for use in transport equipment, such as a truck or a trailer of a truck, comprises at least one steering knuckle4,5on each side of the body3of the transport equipment, a hub piece6,7being fastened by articulation to the steering knuckles, and further, wheels8,9of the transport equipment being fastened to the hub pieces in the steering knuckles, as shown inFIG. 1b. According toFIG. 1a, the steering knuckles4,5are fastened to the body3of the transport equipment by means of articulations14and15, and the hub pieces6,7fastened by articulation to the steering knuckles are pivotable to a desired angle with respect to the steering knuckle to which they are fastened; that is, as shown in the figure, the hub piece6is pivotable with respect to the steering knuckle4, and the hub piece7is pivotable with respect to the steering knuckle5, respectively. The rotation of the hub pieces is provided by means of actuators10,11, such as hydraulic actuators, connected to them, and in a corresponding manner, the steering knuckles are also pivotable to a desired angle by means of actuators12,13provided in them.

When one of the steering knuckles4,5in the steering mechanism according to the invention, for example the steering knuckle4, pivots a given angle, the hub piece6in the steering knuckle5on the opposite side of the body simultaneously pivots the same angle or a different angle with respect to the steering knuckle to which it is fastened by articulation.

According toFIGS. 1aand 1b, the hub pieces6,7are connected to each other by a set of levers16,17and18for controlling the mutual pivoting of the hub pieces when either of the steering knuckles is pivoted. The hub pieces6,7comprise a lever arm or they are provided with a lever arm (or a lever-arm-like shoulder)2, to which one or more actuators10,11(as well as the set of levers16to18) can be connected to enable the pivoting of the hub piece.

The set of levers16to18comprises at least three lever arms, one17of the lever arms being fastened by an articulation21to the body3, equally spaced from the steering knuckles on the different sides of the body, that is, between the steering knuckles on the different sides. However, the articulation21does not necessarily have to be equally spaced from the steering knuckles, but in contrast to the figures it may be closer to one of the two steering knuckles.

As shown inFIGS. 1aand 1b, the steering knuckles4,5are fastened to the body3by substantially vertical articulations14,15, and also the hub pieces6,7are fastened to the steering knuckles4,5by substantially vertical articulations19,20. However, it is feasible that the articulations of the steering knuckles and the hub pieces are not vertical, in other words that they deviate from the vertical direction.

The actuators12,13driving the steering knuckles4,5can be fastened to each steering knuckle4,5concentrically by that articulation19,20of the hub piece6,7in the steering knuckle, by which the hub piece6,7is fastened to the respective steering knuckle4,5. The actuators10to13are all fastened at one end to the body3; in other words, they are supported by the body3.

Also, the actuators10,11for driving the hub pieces6,7can be fastened to the respective steering knuckle4,5concentrically to that articulation14,5in the steering knuckle, by which the steering knuckle4,5is fastened to the body.

FIG. 2ashows the operation of the steering mechanism according to the invention for steering the transport equipment, when the transport equipment is turned to the right (the initial travel direction of the transport equipment as well as the rotation direction of the wheels being indicated with an arrow). As shown in the figure, when one of the steering knuckles, i.e. the steering knuckle4on the right hand side of the figure, is pivoted by the actuator13about the articulation14,15arranged in the body3, the hub piece6therein, i.e. in the pivoting steering knuckle, remains non-pivoted with respect to the steering knuckle4to which it is fastened by articulation, wherein the other steering knuckle5simultaneously remains non-pivoted in its articulation14arranged in the body3, and the hub piece7therein thus pivots with respect to the steering knuckle5to which it is fastened by articulation. Depending on the dimensions of the steering mechanism, the wheels can also be oriented parallel to each other, but there may also be a slight angular difference between them; in other words, they are thus not turned quite in the same direction, as can be seen in the figure.

FIG. 2bshows the steering mechanism in a perspective view of the situation ofFIG. 2a, that is, when turning to the right.

As shown in the figure, the steering knuckle4on the right hand side is turned outwards from the body3; in other words, it is turned counter-clockwise, by means of the actuator13. The steering knuckle5on the other side of the body3is not pivoted; that is, it is placed against the body3. However, the hub piece7in the steering knuckle is pivoted by the actuator11.

In the steering mechanism, each steering knuckle4or5, i.e. the one on each side, consists of at least two elongate pieces (4′,4″,5′,5″) connected to each other by a connecting part22. The connecting part can be, for example, welded between the elongate pieces. However, within the scope of the inventive idea it is also possible to contemplate a solution where only one elongate piece, in which the hub piece is fitted, is provided on each side. Members for providing the suspension of the steering knuckle, for example springs, can be fitted between the elongate pieces, but these are not marked in the figures.

FIG. 3ashows the operation of the steering mechanism according to the invention for steering the transport equipment, when the transport equipment is turned to the left (the initial travel direction of the transport equipment as well as the rotation direction of the wheels being indicated with arrows). As shown in the figure, when one of the steering knuckles, i.e. the steering knuckle5on the left hand side in the figure, is pivoted by the actuator12about the articulation14arranged in the body3, the hub piece7therein, i.e. in the pivoting steering knuckle, remains non-pivoted with respect to the steering knuckle5to which it is fastened by articulation, wherein the other steering knuckle4simultaneously remains non-pivoted in its articulation15arranged in the body3, and the hub piece6therein thus pivots with respect to the steering knuckle4to which it is fastened by articulation.

FIG. 3bshows the steering mechanism in a perspective view of the situation ofFIG. 3a, that is, when turning to the left. As shown in the figure, the steering knuckle5on the left hand side is turned outwards from the body3; in other words, it is turned clockwise, by the actuator12. The steering knuckle4on the other side of the body3is not pivoted; that is, it is placed against the body3. However, the hub piece6in the steering knuckle is pivoted by the actuator10.

It will be obvious for a person skilled in the art that with technological developments, the basic idea of the invention can be implemented in many different ways. Thus, the invention and its embodiments are not limited to the above-described examples but they may vary within the scope of the claims. Consequently, various features can be omitted, modified, or replaced with equivalents, and features presented in this application can be combined, to provide various combinations.

The steering mechanism according to the invention can be dimensioned such that when one of the steering knuckles pivots a given angle, the hub piece in the steering knuckle on the other side of the body simultaneously pivots an equal or different angle with respect to the steering knuckle to which it is fastened by articulation.

The steering mechanism according to the invention is advantageously fitted in a mining truck (such as, for example, an articulated mining dumper) or a trailer for the same. The steering mechanism can be fitted in a mining truck (dumper) or in the rear part of a trailer for the same, but it is also feasible that the steering mechanism is fitted in the front part (front body).

Within the scope of the inventive idea it is feasible to implement the steering mechanism so that the actuators are used for controlling both the steering knuckles to pivot simultaneously and that the hub pieces are thus pivoted at the same time.

By dimensioning of the set of levers, i.e. by the length of the lever arms and by selecting their fastening points to the hub piece (the lever arm of the hub piece) and to the body of the transport equipment (the articulation of the middlemost lever arm on the body), it is possible to provide a path for the transport equipment that follows or corresponds to the turning radius of the wheels.