It is also concerned with combinations of such an improved rail bogie with related pieces of equipments to form a locomotive unit for driving the so-formed train and/or a cabin unit.

Brief description of the prior art Rail bogies of the above mentioned type are already known in the art.

Such bogies usually comprise two axles, a rigid chassis and a pair of oppositely oriented fifth-wheels that are mounted on top of the chassis and adapted to be hooked to king pins provided at the front and/or rear of semi-trailers or to form at grain for riding on rails.

By way of examples, reference can be made to the following U. S. patents: 4,416,571 4,547,107 4,669,391 4,685,399 4,773,335 4,766,818 4,938,151 5,107,772 Amongst the above patents, U. S. patent Nos. 4,416,571 and 4,685,399 disclose twin axle rail bogies in which the fifth-wheels are mounted directly onto the chassis and not adjustable in height. U. S. patent No. 4,547,107 discloses a twin axle rail bogie in which each of the fifth-wheels can individually be lifted up by means of a power jack. U. S. patent No. 5,107,772 filed in the name of the present inventor discloses

a twin axle rail bogie in which the two fifth-wheels are mounted onto a"floating" platform that is mounted on top of the chassis. Lifting means preferably of the pneumatic type, are provided to vertically move the platform and fifth-wheels in unison with respect to the chassis between low and high positions. Guiding means and locking means are also provided to guide the platform while it moves up, and to look it to the chassis when it has reached its high position.

SUMMARY OF THE INVENTION A fist object of the present invention is to provide an improved twin axle rail bogie which is of the same type as above, but whose structure is simpler than and yet as efficient as those of the known rail bogies.

This first object of the invention is achieved with a rail bogie adapted to be hooked with semi-trailers or similar road vehicles to form a train for riding on rails, which rail bogie comprises: -a chassis mounted on a pair of wheel assemblies via a suspension system, said chassis having a longitudinal axis; -a first and second oppositely oriented fifth wheels mounted on top of the chassis, each of the fifth wheels being centered on the longitudinal axis and positioned in such a manner as to be inserted under a semi-trailer or a similar road vehicle and be connected thereto by means of a king pin; and -means for moving the first and second fifth wheels up and down in unison; This rail bogie is characterized in that: -the first fifth wheel is pivotably mounted about a first horizontal axis at one end of a lifting frame that is pivotably mounted about a second horizontal axis onto a supporting structure rigidly fixed to the chassis, the first and second horizontal axes being transverse to the longitudinal axis of the bogie; -the second fifth wheel is pivotably mounted about a third horizontal axis on top of a tilting body that is pivotably mounted about a fourth horizontal axis onto the supporting structure, the third and fourth horizontal axes being transverse to the longitudinal axis of the bogie, and

-the means for moving the first and second fifth wheels includes: --a power jack extending longitudinally and centrally with respect to the chassis, the power jack having first and second opposite ends; and --first and second linking means operatively mounted between the first end of the power jack and the lifting frame and between the second end of the power jack and the tilting body, respectively, the first and second linking means being devised in such a manner that actuation of the power jack causes the first and second opposite ends of the power jack to move away from each other and the lifting frame and tilting body connected thereto by said first and second lifting means to simultaneously pivot about the second and fourth horizontal axes, respectively, and thus to lift up or down the first and second fifth wheels.

Another object of the invention is to provided an improved rail bogie as defined hereinabove, which incorporates one or two electric motors for driving one or both of its wheel assemblies. Such motors can be supplied with electric energy by means of a retractable arm sized to reach the trolley were usually provided above the electric railways. Alternatively the motors can be supplied through a power generator mounted into a semi-trailer hooked to the rail bogie. Such a"combination"forms a locomotive unit that can be used to drive a train formed of semi-trailers and rail bogies according to the invention.

A further object of the invention is to provide combinations including an improved rail bogie as defined hereinabove, with one or more related pieces of equipment. Such pieces of equipment may include the semi-trailer with a power generator mentioned hereinabove. They may also include a cabin unit hookable to a rail bogie according to the invention in order to accommodate the driver (s) of the train.

BRIEF DESCRIPTION OF THE DRAWINGS The objects of the invention will be better understood upon reading the following non-restrictive description of several preferred embodiments thereof made with reference to the accompanying drawings, in which:

Figs. 1 and 2 are side elevational views of a rail bogie according to a first embodiment of the invention, having its opposite fifth-wheels in low and high positions, respectively; Fig. 3 is a top plan view of the rail bogies shown in Figs. 1 and 2; Fig. 4 is a view similar to Fig. 2, showing the mechanism used to lift up and hold the fifth-wheels in high position; Fig. 5 is a view similar to Fig. 4, showing the fifth-wheels in low position ; Fig. 6 is a top plan view of the fifth-wheels and mechanism used to lift them up; Fig. 7 is a top plan view of the supporting structure provided on top of the frame of the rail bogie for the fifth-wheels lifting mechanism; Fig. 8 is a side elevational view of the supporting structure shown in Fig. 7; Figs. 9 and 10 are side elevational views of the fifth-wheels and mechanism used to lift them up, when the fifth-wheels are in low and high positions, respectively; Fig. 11 is a side elevational view of a rail bogie according to a second embodiment of the invention, this rail bogie incorporating an electric motor for driving one of its axles, and a retractable arm sized to reach a trolley were in order to supply electric energy to the motor; Figs. 12 and 13 are side elevational views of a locomotive unit comprising a pair of motorized bogies on which is mounted a semi-trailer incorporating a power generator to supply electric energy to the bogies; Figs. 14 and 15 are top and side elevational views of a casing unit for connection to a rail bogie according to the invention; and Figs. 16 and 17 are top and side elevational views of another locomotive unit comprising a semi-trailer that incorporates a power generator and is permanently connected to a motorized bogie.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION The basic structure of the rail bogie 1 according to the first preferred embodiment of the invention illustrated in the drawings is shown in Figs. 1 to 10. This bogie 1 is of the twin-axle type and comprises a chassis 3 mounted on a pair of wheel assemblies 5,7 via a suspension system knownper se (an example of such a suspension system is disclosed in international laid-open patent application WO 96/12636 in the name of the present inventor). A braking system known per se may also be provided. A pair of oppositely oriented fifth-wheels 9,11 are mounted on top of the chassis 3. Each fifth-wheel is positioned in such a manner as to be insertable under the bottom front and/or rear portion of a semi-trailer or any similar road vehicle, and then be connected to the same by means of a king pin downwardly projecting from said bottom front and/or bottom rear portions. Once again, this kind of assembly that permits to form a train for riding on rails, is known per se and needs not be further described.

The fifth-wheels 9,11 are mounted onto the chassis 3 in such a manner as to be movable up and down in unison by mans of a single power jack 13 of a conventional structure, which extend longitudinally and centrally onto the chassis 3.

This power jack 13 is preferably pneumatic but it could be hydraulic or electric.

More specifically, as is better shown in Figs. 4,5,9 and 10, the left hand side fight-wheel 9 is pivotably mounted at one end of a lifting frame 15 comprising two parallel arms pivotably connected to a supporting structure 17 by a pair of brackets 19 (see Figs. 7 and 8). The supporting structure 17 is rigidly fixed in the upper portion of the chassis 3 and both the fifth-wheel 9 and the lifting frame 15 are pivotable about horizontal axes A and B called"first and second horizontal axes"in the appended claims, that are transverse to the longitudinal axis of the bogie. As can be seen in the illustrated embodiment, the lifting frame 15 projects from the supporting structure 17 in the left hand side direction.

The lifting frame 15 is connected to the free end of the piston 21 of the power jack 13 by means of first linking means consisting of a pair of rigid links 23.

These links 23 have"upper"ends connected to the bottoms of the arms of the lifting frame 15 close to the end of the same so as to be pivotable about an horizontal transverse axis C called"fifth horizonal axis"in the appended claims. The links 23 also have

"lower"ends pivotably connected about an horizontal transverse axis D (called"sixth horizontal axis"int the appended claims) to a transverse member 25 slidably mounted onto a pair of first supporting rails 29 forming apart of the supporting structure 17. The transverse member 25 is itself pivotably connected about an horizontal transverse axis E to the free end of the piston 21 of the power jack.

As is better shown when comparing in Figs. 9 and 10, actuation of the power jack 13 causes the piston 21 to expand in the left hand side direction and the links 23 to pivot in such a manner as to lift up the frame 15, thereby causing lifting of the fifth-wheel 9. As is also shown in the drawings, a pair of wedge-shaped support members 27 are mounted under the arms of the lifting frame 15 in order to prevent this frame from moving down up too close to the rails 29 and thus from the damaging the links 23 and their pivots.

At the opposite end of the bogie 1, the fifth hand side fifth-wheel 11 is pivotably mounted on top of a tilting body 31 about an horizontal transverse axis F called"third horizontal axis"in the appended claims. The tilting body 31 comprises an upper member comprising two parallel arms 33 on which the fifth-wheel is mounted, and a lower member comprising two parallel arms 35. These arms 33, 35 extend in intersecting planes and are pivotably connected at one end to both each other in pair and the supporting structure 17 about a common transverse axis G (called"fourth horizontal axis"in the appended claims) by means of brackets 37 (see Figs. 3 and 7). The other ends of the upper and lower arms 33,35 of the body 31 are connected to each other by means of a shock-absorbing springs 41. As can be seen, the other end of each lower arm 35 comprises an upwardly extending projection 42 integral thereto. As can also be seen, the tilting body 31 projects from the supporting structure 17 in the same direction as the lifting frame 15, that is in the left hand side direction.

The tilting body 31 is connected to the rear end of the cylinder 43 of the power jack 13 by means of second linking means consisting of another pair of rigid links 45. These links 45 have"upper"ends connected to the upwardly extending projections 42 of the lower arms 35 of the tilting body 31, so as to be pivotable about an horizontal transverse axis H called"seventh horizontal axis"in the appended claims. The links 45 also have"lower"ends pivotably connected about an horizontal transverse axis I (called "eighth horizontal axis"in the appended claims) to another transverse member 47

slidably mounted onto a pair of second support rails 49 forming part of the supporting structure 17 (see Fig. 8).

As is better shown when comparing Figs. 9 and 10, actuation of the power jack 13 causes the cylinder 43 of the power jack 13 to move to the right hand side direction and the links 45 to pivot in such a manner as to tilt up the tilting body about the axis G, hereby causing lifting of the fifth-wheel 11.

Thus, as it can now be better understood, both fifth-wheels 9 and 11 are lifted up by actuation of the power jack 13 that is exclusively connected to the sliding transverse members 25 and 47.

The fact that only one power jack 13 is used to lift up both fifth-wheels does not mean that these fifth-wheels necessarily move up simultaneously. Indeed, if only one of the fifth-wheels is loaded, actuation of the power jack will result in a lifting of the other fifth-wheel first, followed, when the first lifting is compelled, with a lifting of the loaded fifth-wheel.

Fig. 11 of the drawings shows a rail bogie 101 according to a second embodiment of the invention. This rail bogie 101 is identical to the rail bogie 1 that has just been described, in terms of wheel axles, suspension, opposite fifth-wheels and mechanism to lift them up. As a matter of fact, the bogie 101 distinguishes from the boatie 1 only in that: -it incorporates an electric motor 103 transverse mounted within its chassis for driving one of its axles via a transmission gear box 105; and -it also incorporates a telescopically retractable arm 107 which is sized to reach in expended position, a trolley wire 109 like those usually provided above the electric railways so as to supply electric power to the motor 103.

In practice, the bogie 101 may comprise one motor 103 as shown in Fig.

11, or tow motors 103,103' (one for each axle) as is shown in the right hand side of Fig.

12. The retractable arm 107 is optional only. Indeed, when there is no trolley wire, such arm 107 is of no use and thus not required. In such a case, use can be made of a semi- trailer 111 that is hitchable onto a pair of bogies 101 and comprises a power generator to supply the requested electric energy to the motors 103,103' (see Figs. 12 and 13).

The resulting assembly forms a locomotive unit that can be used to drive a train formed of a number of semi-trailers hitched to each other through a

corresponding number of bogies 1.

The locomotive unit shown in Fig. 12 incorporates two bogies 101, one of which comprises two motors 103,103'. Its power generator is devised to provide a power of 1900 HP. The unit shown in Fig. 13 incorporates two bogies 101 each comprising only one motor 103. Its power generator is thus devised to produce a power of 1200 HP only.

In both cases, the trailer 111 of each unit comprises a radiator 113, a diesel reservoir 115, an electric control panel 117, an electric generator 119, a diesel motor 121 to operate the generator 119, an air reservoir 123 and a compressor 125 to operate the piston 13 of the bogies 1,101 and the braking means of such bogies, a hydraulic pump 127 and, when required, a dead weigh 129. All thee components are standard and the way they cooperate is well known to those skilled in the art. As a matter of fact, they are present in all the existing diesel-powered electric locomotives.

To complete the train, a cabin unit 131 can also be provided, as is shown in Figs. 14 and 15. Such a cabin unit has a rear portion 133 hitchable to a bogie 1 (not shown) and comprises two sets of wheels on tis front portion, including one rigidly mounted set of wheels 135 for use on rails and another upwardly retractable set of wheels 137 for use on road to facilitate displacement and installation of the cabin unit 131. As any conventional cabin unit, the cabin unit 131 may comprise the following components in a plurality of separate chambers closed with doors: a power generator 139, a set of batteries 141, a battery charger 143, an electric panel 145, an air exchanger 147, a microwave oven 149, a refrigerator 151 and a toilet bowl 153.

Instead of using a locomotive unit consisting of a semi-trailer 111 hitchable onto bogies 101, use can be made of a locomotive unit consisting of semi- trailer 161 incorporating a powered bogie as part of its structure, as is shown in Figs. 16 and 17. More particularly, the semi-trailer 161 comprises two set of wheels 171,173 for use on rails and a retractable set of wheels 175 for use on road. The wheels 171 and 173 are driven by a power generating equipment contained in the trailer, which, like the one previous disclosed comprise a radiator 177, an electric panel 179, an electric generator 181, a diesel motor 183, a hydraulic pump 185, an air reservoir 189 and a compressor 191. A fifth-wheel 193 is provided at the rear of the unit 161 for connection to another semi-trailer.

Of course, numerous modifications could be made to the preferred embodiments disclosed hereinabove without departing from the scope of the invention as defined in the appended claims.

Thus, by way of example, in the illustrated embodiments, the lifting frame 15 and tilting body 31 both project from the supporting structure 17 in the same direction. Also, the lifting frame 15 and tilting body 31 are each disclosed as being made of parallel arms that are connected to the power jack 13 by means of rigid links slidably mounted on supporting rails 29,49. Eventhough this is definitively the best mode of realisation contemplated by the inventor, it would also be possible, if such is needed, to devise the lifting frame 15 and tilting body 31 in such a manner that they project from the supporting structure in opposite direction. Similarly, use could be made of a lifting frame 15 and a tiltingly body 31 of a structure different from the illustrated one. For example, each one could be made of one single piece in the form of a plate. The linking means (23,25) could also be devised differently.