AUTOMATIC-ASSEMBLY BRIDGE, RAMP AND THE LIKE

Abstract: The automatic-assembly bridge, ramp and the like comprises a base segment (1) which has, on one face, two sets of wheels (2) provided with positioning means for disengaging from the ground when the bridge, ramp and the like is installed, as well as an articulation (7) for releasably coupling to a tractor (8). A second segment (20) is articulated at one end of the base segment (1) and is constituted by a first track (20a) and a second track (20b) which can be arranged mutually side by side and can be rotated independently from one another so as to be arranged in a transport position, wherein the tracks (20a, 20b) of the second segment (20) are superimposed on the base segment (1), and in an installation position, wherein the tracks (20a, 20b) are arranged substantially along the extension of the base segment (1). One of the tracks acts as ballast during the rotation of the other track.

Description: The present invention relates to an automatic-assembly bridge, ramp and the like. As known, bridges, ramps or the like which can be installed in a relatively short time in case of natural disasters or military conflicts are already commercially available. Such bridges currently pose considerable problems regarding their transport and installation, since it is necessary to use tracked vehicles to transport them to the installation site and external lifting means are generally required to put the bridge or ramp in place. Known bridges or ramps are generally provided by means of elements which mutually extend from one another and generally do not have sufficiently wide useful spans. Another disadvantage which can be ascribed to the solutions of the known art is constituted by the fact that the bridges, ramps and the like currently in use require assembly times which are excessively long and are furthermore significantly constrained by the operative limitations of the installation site. An automatic-assembly bridge structure is disclosed by the prior document US-A-3 105 251. Such a bridge shows a base segment and rear and front ramps articulated to both ends thereof, to be first unfolded and then transported to the launching site, long operating times and auxiliary personnel still being necessary. The aim of the invention is indeed to eliminate the above described disadvantages by providing an automatic-assembly bridge, ramp and the like which can be easily transported on roads with a simple tractor for semi-trailers, thus making its transport to the installation site very easy and rapid. Within the scope of the above described aim, a particular object of the invention is to provide a bridge, ramp and the like which does not require external operating means for its assembly since it is automatically assembled, in that the elements which allow its unfolding are directly incorporated, allowing to install it in extremely short times, in the order of about ten minutes, without being substantially affected by the conditions of the installation site. Another object of the present invention is to provide a bridge, ramp and the like which can reach considerable useful lengths without creating dangerous conditions during the installation stage. Not the least object of the present invention is to provide an automatic-assembly bridge, ramp and the like which by virtue of its peculiar constructive characteristics is capable of giving the greatest assurances of reliability and safety in use. The above described aim, as well as the objects mentioned and others which will become apparent hereinafter, are achieved by an automatic-assembly bridge, ramp and the like, with the features recited in claim 1. Further characteristics and advantages will become apparent from the description of a preferred but not exclusive embodiment of an automatic-assembly bridge, ramp and the like, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a schematic lateral elevation view of the bridge, ramp and the like, applied to a transport tractor; figure 2 is a top plan view of the bridge with the elements folded onto the base segment; figure 3 is a schematic top plan view of the bridge after one of the tracks has been positioned; figure 4 is a schematic elevation view of the bridge with the step of rotation of the first track indicated in broken lines; figure 5 is a view of a successive step of rotation of a track with an intermediate stage indicated in broken lines; figure 6 is an elevation view of the installed bridge, with the second track shown before being positioned and indicated in broken lines; figure 7 is a plan view of the bridge with both tracks positioned; figures 8, 9 and 10 are schematic views of possible different kinds of installation of the bridge, ramp or the like according to the invention. With reference to the above described figures, the automatic-assembly bridge, ramp and the like according to the invention comprises a base segment, generally indicated by the reference numeral 1, which is advantageously but not necessarily defined by two sections which are divided longitudinally so that they can be easily transported; during installation , the two sections are rigidly coupled to one another so as to form said base segment. Said base segment 1 may naturally also be provided monolithically. The base segment acts in practice as a mobile frame for road transport. For this purpose, two sets of four tires 2 each are provided at one end of the base segment, preferably the rear end. Said tires 2 are mounted on rockers 3 so that each wheel is independent from the others so as to ensure correct distribution of the weight on the wheel even on uneven ground. The two sets of wheels 2 are provided with an easily adjustable hydropneumatic suspension 4. The vertical positioning of the wheels is adjusted by means of hydraulic pistons 5 which act on the rocker-holder arm 6 so that the set of wheels can be raised or lowered as required and in particular so that it can be retracted at least partially within the base segment so as to disengage from the ground when the bridge or ramp is installed. On each set, the two rear wheels are equipped with pneumatic brakes, according to international norms, complete with all auxiliary elements. Compressed air is drawn from the tractor, and an auxiliary compressed air tank is furthermore accommodated in the base segment. Said base segment defines, at the other end but on the same face, an articulation 7 for its articulated coupling to the tractor 8. A tilt-down flap or skid 9 is pivoted at the front end of the base segment and has the function of facilitating the access of vehicles to the bridge by eliminating the difference in level on the access side which occurs due to the different inclinations which the bridge may assume. Said tilt-down flap is actuated by a front hydraulic piston 10 which is hinged or pivoted to the base segment at one end and, at the other end, to a gusset 11 rigidly associated with the tilt-down flap or skid 9. Hydraulic jacks 12 are provided at the front end of the base segment and have the function of lifting and supporting the base segment in its front part during the operations for uncoupling it from the tractor and for coupling it thereto. Rear stabilizers 13 are furthermore arranged proximate to the set of wheels 2 and can be extracted and lowered hydraulically from the base segment so as to ensure the necessary stability during the opening and closure of the segments, as will become apparent hereinafter, and to make sure the base segment rests properly on the ground when the bridge is in operating position. In a middle region, the base segment furthermore defines a seat for the accommodation of a hydraulic control unit 14 which supervises the operation of the bridge's hydraulic systems. The pipes directed toward the secondary hydraulic services are connected directly to the control unit, while the pipes for the primary services, i.e. those required to open and close the segment, are made of steel as regards the section provided inside the base segment and are then connected by means of very high-pressure flexible tubes to the successive segments where the opening and closure cylinders are provided. The base segment is pivoted at its rear end by means of large-size hinges 15 to a second segment, generally indicated by the reference numeral 20, which is defined by two tracks 20a and 20b which are arranged side by side along their longitudinal extension. Brackets 21 are provided at the rear end of the base segment, and tension elements 22 are articulated thereto; in turn, said elements are connected to sliding heads 23 of hydraulic cylinders for lifting the second segment which are indicated by 24 and are accommodated inside said second segment. The two tracks 20a and 20b can be folded over independently from one another by means of the hydraulic actuation of the lifting cylinder 24, which rotates each track of the second segment with respect to the base segment by means of the tension element provided between the head of the hydraulic cylinder 24 and the bracket 21. In this movement, the hydraulic cylinder exerts a traction force, during a first rotation step, until the second segment arranges itself substantially vertically with respect to the base segment; once said second segment has become vertical, said cylinder acts as braking element until positioning is completed. This kind of coupling allows a mutual rotation of approximately 200° about the hinge 15 which is provided by means of a single hydraulic cylinder for each track, as does not occur in the solutions of the known art. An end segment 30 is pivoted to the other end of the second segment and is also constituted by a first track 30a and by a second track 30b which are pivoted to the second segment by means of a second hinge 29. Each track of the third segment has a semi-circular element 31 rigidly associated therewith concentrically to the hinge 29; said semi-circular element has an accommodation for a metallic cable 32 which is connected to hydraulic cylinders 35 for rotating the third segment which are accommodated in the second segment. The two tracks of the third segment 30 are turned over by virtue of the hydraulic movement performed by means of the hydraulic piston 35. An important characteristic of the invention is constituted by the fact that one of the two tracks acts as ballast for the other track, i.e. during the step of installation of the bridge one track remains initially folded on the base segment while the other track is lifted, rotating it, by overturning the second arm with respect to the base segment and the third segment with respect to the second segment until they are arranged in the required position, as illustrated schematically in figures 7 to 10. Once one track has been completely unfolded and positioned, the other track can be unfolded. As is thus apparent, an automatic-assembly bridge is provided which includes all the means required for its unfolding and folding without having to resort to external lifting devices. Another characteristic aspect is furthermore constituted by the fact that the mutual rotation between the segments is obtained by means of hydraulic cylinders of appropriate size which act between one segment and the other. The fact that a part of the segments themselves is used as ballast during the unfolding of the other part of the segments is furthermore very important. This characteristic allows to always have maximum safety conditions during the bridge installation step. The invention thus conceived is susceptible to numerous modifications and variations, all of which are within the scope of the inventive concept as defined by the appended claims. All the details may furthermore be replaced with other technically equivalent elements. In practice, the materials employed, so long as compatible with the specific use, as well as the dimensions and contingent shapes, may be any according to the requirements.

Claims: Automatic-assembly bridge, ramp and the like, comprising a base segment (1) which has, on one face, at least one set of wheels (2) and means(7) for releasably coupling to a tractor (8), a second segment (20) being articulated to one end of said base segment (1), said second segment (20) being constituted by a first track (20a) and a second track (20b) which can be arranged mutually side by side and rotated independently from one another so as to be arranged in a transport position, wherein said tracks of said second segment (20) are superimposed on said base segment (1), and in an installation position, wherein said tracks (20a, 20b) are arranged substantially along the extension of said base segment (1), one of said tracks being adapted to act as ballast during the rotation of the other track, characterized in that it further comprises a third segment (30) articulated to said second segment (20) at the opposite end with respect to the articulation of said second segment to said first segment (1), said third segment being constituted by a first track (30a) and by a second track (30b) which can be arranged mutually side by side and can be rotated independently from one another, said at least one set of wheels (2) being provided with positioning means (5) for disengaging from the ground when the bridge, ramp and the like is installed. Bridge, ramp and the like, according to claim 1, characterized in that said at least one set of wheels (2) is mounted on a system of rockers (3) for distributing weight, said at least one set of wheels being controlled by a hydropneumatic accumulator (4). Bridge, ramp and the like, according to claims 1 and 2, characterized in that said positioning means for said at least one set of wheels (2) are constituted by hydraulic pistons (5) which act on the rocker-holder arm (6) for the at least partial retraction of said at least one set of wheels into the body of said base segment (1). Bridge, ramp and the like, according to one or more of the preceding claims, characterized in that said means for releasably coupling to a tractor are constituted by an articulation (7). Bridge, ramp and the like, according to one or more of the preceding claims, characterized in that it comprises a tilt-down flap (9) hinged to said base segment (1) on the opposite side with respect to said second segment (20), said tilt-down flap being actuated by an auxiliary hydraulic piston (10) connected between said base segment and gussets (11) fixed to said tilt-down flap (9). Bridge, ramp and the like, according to claim 4 and one or more of the preceding claims, characterized in that it comprises hydraulic jacks (12) arranged proximate to said articulation (7) and adapted to support said base segment (1) during the coupling of the base segment to said tractor (8) and during the uncoupling therefrom. Bridge, ramp and the like, according to one or more of the preceding claims, characterized in that it comprises rear stabilizers (13) which can be extracted from said base segment (1) to position said base segment. Bridge, ramp and the like, according to one or more of the preceding claims, characterized in that it comprises a hydraulic control unit (14) supported by said base segment (1). Bridge, ramp and the like, according to one or more of the preceding claims, characterized in that said second segment (20) is pivoted to said base segment (1) by means of a hinge (15) arranged at the rear end of said base segment. Bridge, ramp and the like, according to one or more of the preceding claims, characterized in that it comprises brackets (21) which protrude from said base segment (1) at its rear end, tension elements (22) being pivoted thereto and being hinged, at the other end, to sliding heads (23) of hydraulic lifting cylinders (24) accommodated in said second segment (20), the sliding of said sliding heads (23) being adapted to generate the mutual rotation between said second segment (20) and said base segment (1). Bridge, ramp and the like, according to claim 1, characterized in that said third segment (30) has a semi-circular element (31) arranged concentrically to the rear hinge (29) for pivoting to said second segment (20), said semi-circular element (31) defining the accommodation of a cable (32) connected to hydraulic cylinders (35) for lifting the third segment (30) which are supported by said second segment (20). Bridge, ramp and the like, according to claim 1, characterized in that the unfolding of said segments (20, 30) is performed by initially unfolding completely one track (20a, 30a) of said second (20) and third segments (30) and by subsequently unfolding the second track (20b, 30b) once the first track has been positioned.

Inventors: REITER, RUDOLF
Applicants: REITER & CRIPPA INDUSTRIALE S.P.A.
Application year: 1989
Main classification: E01D15
IPC codes: E01D15