| WO/2007/056989 | CANOPY FRAME COMPRISING A LOCKING MECHANISM |
| JP3902275 | VEHICULAR OPEN/CLOSE ROOF |
| WO/2000/012334 | TARPAULIN STRUCTURE |
DAVIDE, Amato (Piazza Risorgimento 16, Pordenone, I-33170, IT)
| CLAIMS 1 Actuation system for a canvas for covering (20) an open top-body (12), comprising centerings (16) slidable with their own feet (17) on the top of the lateral side panels (14) of the top-body to support and open out/pack the covering canvas, and means for moving the centerings above the side panel so as to open out/pack the covering canvas, characterised in that the movement means comprise a set of rigid elements, operatively coupled with one another and with a set of centerings, configured so as to form a flat kinematic chain adapted to pull the centerings, wherein the rigid elements are connected so that, by actuating at least one of them, the motion is transmitted to all the centerings of the group and/or to the remaining rigid elements making the centerings of the set come closer together or spread apart. 2. Actuation system according to claim 1, comprising means for actuating the at least one rigid element. 3. Actuation system according to claim 2. wherein the means for actuating comprise a linear actuator which is connected between the at least one rigid element and a centering or another rigid element. 4. Actuation system according to claim 3, wherein the linear actuator comprises a hydraulic or pneumatic piston fed by an oil or compressed air circuit. 5. Actuation system according to claim 2, wherein the means for actuating comprise an electric motor, which is mounted on a centering or a rigid element and is adapted to actuate the at least one rigid element. 6. Actuation system according to any one of the previous claims, wherein two centerings of the set are connected to each other by at least two rigid elements, where each rigid element is hinged with a respective centering and the at least two rigid elements are hinged to one another at a point positioned between the two centerings or connected therein through a connection member. 7. Actuation system according to claim 6, comprising for each of said at least ' two rigid elements, a rigid arm, that is hinged between each of said rigid elements and a movable hinging point guided on one of said at least two centerings, 8. Actuation system according to claim 7, wherein the hinging point of the two rigid elements on the respective centering is guided in a movable manner on said centering. 9. Actuation system according to claim 6 or 7, wherein each of the two rigid elements has a toothing, engaged with the toothing of the other rigid element, so that the motion of the first rigid' element is transmitted to the other rigid element through meshing. 10. Actuation system according to claim 9, wherein the toothing is present at one end of the rigid elements, the same end being hinged to the centering. 11. Actuation system according to any one of the previous claims 1 to 5, wherein two centerings of the set are connected to one another by at least four rigid elements configured in a pantograph-like manner which have a common hinging point on one centering of said two and at least one common hinging point or a connection member positioned between the two centerings. 12. Actuation system according to any one of the previous claims 6 to 11, wherein the covering canvas is fixed at the common hinging point of two rigid elements, so that the covering canvas is folded or laid out at said point when the centerings come closer together or are spread apart, respectively. 13. Actuation system according to any one of the previous claims 6 to 11, wherein the covering canvas is fixed to the connection member between two rigid elements, so that the covering canvas is folded or laid out at said point when the centerings come closer together or are spread apart, respectively. 14. Actuation system according to any one of the previous claims, comprising sliding anchoring means provided at the feet of the centerings for anchoring the centerings in a slidable manner to the side panel of the body. 15. Actuation system according to any one of the previous claims, comprising means for turning over the centerings as a whole when they are maximally close together and packed at one end of the body, said means' for turning over being configured to lift the feet of the centerings from the side panel by making them rotate about an axis parallel to the side panel itself. |
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TECHNICAL FIELD OF THE INVENTION
The invention concerns an actuation system for covering canvas of top-bodies, in particular bodies of heavy vehicles given as an example hereby.
In trucks, see for example EP 1 884 386, a canvas is used to cover a trailer top body. The canvas (see also fig. 1 of EP 1 738 946) is supported by centerings or arches sliding on the side panel of the body which are hauled by a ring of rope, one for each side of the body, actuated by an electric motor. A description of such a rope system can also be wholly seen, for example, in EP 1 738 946. Each foot of the centerings has a skid mounted on it for better sUding on the side panel. The rope ends are fixed to such a skid, which hauls the first centering and which is actuated by a driving pulley fitted on the shaft of an electric motor.
Not only is the rope system extremely expensive and complex, it is also difficult to mount and maintain. Moreover, the ropes are at the exposed sides of the top-body, vulnerable to weather and/or to unloading/loading means, for example, tipping bodies.
Especially in the field of trucks for transporting material, a problem is therefore that of moving the canvas with improved systems and eliminating the rope system-
The object of the invention is precisely that of proposing an alternative to conventional actuation systems. Such a object is obtained with an actuation system for a canvas for covering an open top body (the body with its side panels delimits a loading volume), comprising ,
- centerings slidable with their own feet on the top of the lateral side panels of the top-body to support and open out/pack the covering canvas, and
- means for moving the centerings above the side panel so as to open out/pack the covering canvas,
characterised in that the movement means comprise
- a set of, preferably elongated, rigid elements, operatively coupled with one another and with a set of centerings, configured so as to form a flat kinematic chain adapted to pujl the centerings, wherein the rigid elements are connected so that, by actuating at least one of them, the motion is transmitted to all the centerings of the group and/or to the remaining rigid elements making the centerings of the set come closer to each other or spread apart from one another.
By kinematic chain it is meant the union of many rigid elements (for example rods, arms, tubes, bars, beams, etc.) obtained with kinematic pairs (preferably hinges or joints),, so that, since the relative speed or the motion of a rigid element is fixed with respect to any other one, also the relative speeds or the motion of all the other rigid elements is unambiguously determined. By fiat kinematic chain it is meant a chain in which, having any one rigid element fixed, the points of the other rigid elements move on planes parallel to one another (in the embodiments described, in particular, on the same plane).
Preferably the actuation system comprises means for actuating the at least one rigid element. Such actuating means can be a manual actuation system, like a crank or a tie-rope, or an assisted one. In both cases the actuating means can be a permanent part of the actuation system or also added or connected when needed. A linear actuator connected between the at least one rigid element and a centering or another rigid element, for example, can be used as actuating means. Preferably in this case the linear actuator comprises a hydraulic or pneumatic piston fed by an oil or compressed air circuit This makes it possible to exploit the reservoir and the circuits already present on trucks.
Furthermore, the actuating means can comprise an electric motor, which is mounted on a centering or on a rigid element and is adapted to actuate the at least one rigid element.
It should be noticed that the position of the actuating means is not essential, since they can be on one or more, fixed or movable, centerings, or on the top-body and acting remotely. The actuation system according to the invention, may involve all the centerings of the top body or subsets thereof, for example to uncover only a part of the top-body at a time. The various groups of centerings actuated according to the invention may have a control which is independent from one another or coordinated, for example, to uncover the entire body by acting simultaneously. Suitable control means, for example an electronic processing unit or a PLC, are advantageous if used for managing the motion of the centerings and if used as controllers of the actuating means.
Preferred solutions for making the moving kinematic chain are the following: - two centerings of the set are connected to one another by at least two rigid elements, where each rigid element is hinged to a respective centering and the at least two rigid elements are hinged or connected to one another in a point located between the two centerings. This solution is valid for example, for moving only two centerings;
- for each of said at least two rigid elements there is a rigid arm hinged between each of said rigid elements and a movable hinging point guided on one of said at least two centerings. In this way the centerings are more stable and a mechanism which transmits the motion to the subsequent centering is obtained;
- as a variant of motion transmission mechanism, each of the two rigid elements may have a toothing, engaged with the toothing of the other rigid element, so that the motion of the first rigid element is transmitted to the other rigid element through the meshing. Preferably, in order to maximize the thrust generated by the resulting lever, the toolhing is at one end of the rigid elements, the same end being hinged to the centering;
-as a further variant of kinematic chain, two centerings of the set may be connected to one another by at least four rigid elements configured in a pantograph- like manner which have a common hinging point on every centering of said two and at least a common hinging point or a connection member located between the two centerings.
It should be noticed that the aforementioned solutions can also be used combined, for a greater stability of the system and/or of the centerings.
It should also be noticed that two rigid elements in the points or at the ends that are between two centerings may be coupled to one another for example, through a connection member or simply through a common hinging point.
In order to avoid that the canvas gets blocked or tangled up in the kinematic chain, the connection member may be exploited, for example a bracket or block, as a support and attachment for the canvas (i.e., the canvas can be fixed on the connection member), so that the canvas is folded or opened out at the connection member when the centerings come closer or move apartj respectively.
In a simple way, two rigid elements can be hinged to the connection member, preferably at their ends, so as to gain opening out stroke for the canvas. With known provisions it is preferable to make sure that the connection member does not rotate when it is pushed by a rigid element to transmit the motion to the next one.
If, on the other hand, two rigid elements have a common hinging point, the connection member may be mounted on this point, or even omitted. In this case the canvas shall thus be directly fixed to the hinging point, for example, with screws or hooks. In order to avoid the accidental lifting of the canvas, sliding anchoring means can be provided at the feet of the centerings, to anchor the centerings in a slidable manner to the side panel of the top body. For example, sliding skids may be used inside a guide fixed on to the top body, but -which cannot be separated from it A shape-coupling may be used, with a T-shaped guide for example, or a cable may be pulled at the sides of the top body and inserted in holes present in the feet of the centerings. Otherwise, small brackets or hooks may be mounted on the feet of the centerings, better if provided with wheels or bearings, to slidingly anchor them to the side panel, which usually has undercuts or grooves which can be exploited for this purpose. Otherwise, a beam or a guide may be mounted on the top body to which a skid of the centering, or its foot directly, are to be shdingly fixed.
The invention allows the centerings to be packed without fixedly connecting them with a cable ring, It can be thought to make the sliding anchoring means also as means for turning over the centerings as a whole when they are maximally close together and packed at one end of the body. The ttiming over means can be configured to lift the feet of the centerings from the side panel by making them rotate about an axis parallel to the side panel itself. For example, an end portion of the aforementioned T-shaped guide could be on one side hinged to the top body and to the other free to oscillate, so as to lift the feet of the centerings when all of them are only engaged in such a portion. All this has the advantage of being able to move the pack of centerings far away from the opening of the top body, and to maximize the useful area during loading/unloading operations. The invention and its advantages shall in any case become clearer by the following description of example embodiments and by the attached drawing, in which:
Fig. 1 shows a 3D view of an actuation system according to the invention with the centerings distant from one another;
Fig. 2 shows a partial 3D view of the actuation system of fig. 1 with the centerings packed up;
Fig. 3 shows a partial 3D view of the actuation system of fig. 1 with the centerings lifted and raised;
Fig. 4 shows a partial enlarged 3D view of the centerings in fig. 1 ;
Fig. 5 shows an enlarged detail of fig. 4;
Fig. 6 shows a partial enlarged 3D view of the centerings in fig. 2;
Fig. 7 shows an enlarged detail of fig. 6;
Fig. 8 shows an enlarged detail of fig. 4;
Fig. 9 shows an enlarged detail of fig. 4;
Figs. 10-12 show, in a side view, diagrams of variants of the actuation system. Fig- 1 shows an actuation system 20 in which centerings ox arches 26, which can slide on the side panel 28 of the top body 24, support a covering canvas (not shown). As an. example only four centerings are shown. The centerings 26, thanks to a displacement mechanism integrated with the centerings or with the side panel, are mechanically shifted without using a rope ring like in the prior art. The centerings 26 have a C shape with ends curved inwards with respect to the top body 24 to form a foot which can slide on the side panel 28. On the foot, a skid may be mounted (not shown), to help the sliding on the side panel 28.
The centerings 26 are connected by rigid rods 30. On each centering 26, except for the first of the series, indicated with 26F which remains fixed, the ends of two rods 30 are hinged in points 62 hinging about an axis X2 substantially parallel to the plane of the side panel 28. To each of said ends, a toothed wheel 60 is coupled. The points 62 are on a plane parallel to the side panel and the size of the wheels 60 is such as to always ensure a reciprocal meshing. The free end of said two rods 30 is hinged at points 52, 54 to a common block or bracket 50- to which a canvas can be fixed or that in any case supports the canvas. The hinging axis at the points 52, 54 is indicated with X4 and it is parallel to the axis X2,
On the first fixed centering 26F, only a rod 3 OF and a linear actuator is rotatably mounted at a point 40, about an axis X3 parallel to the axis X2. It is made up of a body 34 from which a mobile piston 36 comes out The piston 36 is hinged to the rod 3 OF at a point 38, whereas the body 34 is hinged to a spacer plate 32 projecting from the centering 26F. By controlling the stroke of the piston 36, the rod 3 OF can be moved along the centering 26F.
The actuation system 20 works in the following way. From the position in which the canvas is packed (figs. 2, 6 and 7) it moves to the opened out position (figs. 1, 4 5, 8 and 9) actuating the piston 36 in extension which pushes the rod 3 OF downwards, This causes the closest block 50 to be lowered, pushing downwards the other adjacent rod 30. The separation of the two rods 30F, 30 implies the movement of the centering 26 adjacent to the centering 26F. The rotation of the aforementioned rod 30 induces, through the wheels 60, the lowering of the rod 30 which follows in the series, and so on. Therefore, as the piston 36 gradually extends, the centerings 26 gradually move neatly further apart from the centering 26F pushed by the force transmitted by and to all the rods 30. in order to fold the canvas, it is sufficient to bring the piston 36 back and the centerings shall move in the opposite direction. Fig. 10 shows a variant of the system, where the type of kinematic chain made by the rods is changed. Three centerings 86 are shown (only as an example), connected by two rigid rods 88. On each centering 86 the ends of the rods 88 are hinged at hinging points Pi, P2. At an intermediate point P3 between the centerings 86 the two rods 88 are hinged to one another. Between the points Pi, P2 of a centering 86 there is a linear actuator made up of a body 84 and a movable piston 82. At least one of the points PI, P2 is guided in a mobile way on the centering 86, see the arrows, for example, through the coupling of a linear guide and a skid or slider.
This actuation system works as follows. In order to pass from the position of packed canvas to that in which the canvas is opened out, the piston 82 is withdrawn, making the points PI, P2 come closer together. Consequently, the rods 88 rotate and come closer to one another pivoting on the point P3, and also all the points PI, P2 on the centerings 86 come closer. By rotating, the rods 88 move the centerings 86 apart. In order to fold the canvas, it is sufficient to extend the piston 82, with inverse kinematics for the entire system.
Each of the rods 86 may be fixed, and the others move with respect to it; preferably the rod at the end of the series is kept fixed. -
Fig. 11 shows another variant of the system with two rods. At each of three (as an example) centerings 106, two rigid rods 108 are connected through a common hinging point P9. The end of the rods l08 are hinged at the ends of other identical rods at hinging points P8, PlO. Between the points PS, P10 there is a linear actuator made up of a body 104 and a mobile piston 102.
This actuation system works as follows. In order to pass from the position of packed canvas to that in which the canvas is opened out, the piston 102 is withdrawn, making the points P8, P10 come closer. Consequently, the rods 108 rotate and come closer to one another pivoting on the point P9, and this also for all the points P8 : P10 of each pair of rods 108. By rotating, the rods 108 push the centerings 106 in the point P9 and move them away from one another, In order to fold the canvas, it is sufficient to extend the piston 102, with inverse kinematics for the entire system.
Each of the rods 86 may be fixed, and the others move with respect to it; preferably the one at the end of the series is kept fixed. Moreover, the rods 108 may be replaced by shorter rods, which extend between the points P9-P8 and P9-P10.
Fig. 12 shows another variant of the system, with four rods per centering. At each of three (as an example) centerings 96 > two rigid rods 98 are hinged at one end, at hinging points P4. The free ends of the rods 98, are hinged to the ends of other identical rods or arms at hinging points P7, Two shorter rods 97 are hinged at one side to a rod 98 at a point P6 and at the other to the centering 96 in a movable point P5. On the first centering (on the left in fig, 12), which is fixed to the side panel, only a rod 98 is hinged, which can be actuated by a linear actuator made up of a body 94 and a mobile piston 92. The body 94 is hinged to the first centering and the piston is hinged to its only rod 98.
This actuation system works as follows. In order to pass from the position of packed canvas to that in which the canvas is opened out, the piston 92 is extended, making the coupled rod 98 rotate, pushing the adjacent one. The close point P7 lowers and pulls the rod 98 downwards to its right Simultaneously, the points P6 and P5 are lowered, and this motion is transmitted through the rods 97 to the rods 98 of the next centering, and so on. It can be seen that the rods 97 and the end lower portion of the rods 98 restrained to the centerings 96 form an articulated parallelogram, which at the points P4 3 P5 pushes the centering 96 and at the points P6 propagates the motion along the entire cascade of rods and centerings towards the right in fig. 12. In order to fold the canvas, it is sufficient to withdraw the piston 92, with reverse kinematics for the entire system.
Two points PS may also be made, one for each rod 97,
It should be noticed that all the points P1-P10 are hinging points about an axis substantially parallel to the plane of the side panel.