Abstract:
An agricultural machine for grouping windrows together or for windrowing products lying on the ground includes a main frame supporting a central gathering and windrowing device and two side gathering and windrowing devices connected to support arms that extend laterally during work. Each of the side support arms is articulated relative to the main frame on a substantially vertical axis about which it is foldable at an angle of approximately 90° for transport and each of the side gathering and windrowing devices is articulated on its support arm around a substantially horizontal axis about which it is foldable upwards at an angle of approximately 90° to obtain a reduced machine width for transport.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   The present application is a continuation of PCT application Serial No. PCT/FR04/050520, filed on Oct. 21, 2004, which claims priority to FR 03/12665, filed on Oct. 29, 2003, the contents of each of which are incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an agricultural machine for grouping windrows together or for windrowing products such as grass, hay or straw that are lying on the ground. This machine comprises in particular a main frame supporting a central gathering and windrowing device that is connected to said main frame and two side gathering and windrowing devices that are connected to support arms that extend laterally relative to the main frame, which side devices and central device are substantially in line and extend substantially perpendicular to the direction of travel of the machine during work. 
   2. Discussion of the Background 
   On a machine of this kind, the side gathering and windrowing devices may be folded upward for transport, by means of their support arms, about substantially horizontal axes. This arrangement makes it possible to reduce the width of the machine in order to further displacements on tracks and roads. However, in this position, the height of the machine is considerably increased. This hampers rearward visibility and impairs the stability of the machine due to the distance of its center of gravity from the ground. It then risks overturning when passing over major unevennesses or in a bend. 
   SUMMARY OF THE INVENTION 
   The object of the present invention is to overcome the aforementioned drawbacks. It must notably propose a machine that is as described in the introduction and that can be transposed simply into a transport position in which it retains good stability. 
   Accordingly, an important feature of the invention lies in the fact that each side support arm of a side gathering and windrowing device is articulated relative to the main frame on a substantially vertical axis about which it can be folded at an angle of approximately 90° into a transport position in which said side gathering and windrowing devices are situated either side of the central gathering and windrowing device and that each side gathering and windrowing device is articulated on its support arm by means of a substantially horizontal axis directed substantially perpendicular to the direction of travel in the working position, about which axis it can be folded upward at an angle of approximately 90° for transport. 
   This arrangement makes it possible to fold the side gathering and windrowing devices into a position in which they are directed in the direction of travel and in which their width is reduced. In this position, the machine is compact. Its narrow width makes it possible to move it on roads and its center of gravity that remains relatively low gives it good stability. 
   According to another feature of the invention, the frame comprises mechanisms for immobilizing the side gathering and windrowing devices in the transport position. Each of these immobilization mechanisms consists advantageously of an arm that is rigidly fastened to the frame and on which is articulated a hook actuated by a system of levers. This system forms an articulation of the knuckle-joint type that is controlled by means of a hydraulic cylinder. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the invention will emerge from the following description that refers to the appended drawings which represent, as a nonlimiting example, an embodiment of the machine according to the invention. 
     In these drawings: 
       FIG. 1  represents a top view, with partial sections, of a machine according to the invention in the working position, 
       FIG. 2  represents a side view, on a larger scale, of a side gathering and windrowing device in the working position, 
       FIG. 3  represents a view similar to that of  FIG. 2  with the side gathering and windrowing device raised, 
       FIG. 4  represents a top view of the machine according to the invention in the transport position, 
       FIG. 5  represents a side view of the machine according to the invention in the transport or setting down position, 
       FIG. 6  represents a detail view of an immobilization mechanism in the released position, 
       FIG. 7  represents a detail view of the immobilization mechanism in the locked position. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   As represented in  FIG. 1 , the machine according to the invention comprises a main frame  1 . The latter consists of a central beam  2  which has at its front end a coupling head  3  for coupling it to a tractor making it possible to drive and move the machine in the direction of travel A. The beam  2  has at its rear end a cross bar  4  to which are connected two displacement wheels  5  and  6  which rest on the ground. Said cross bar  4  supports a central gathering and windrowing device  7  and two side gathering and windrowing devices  8  and  9 . The latter are substantially in line and extend substantially perpendicular to the direction of travel A during work. 
   In the example shown, the gathering and windrowing devices  7 ,  8  and  9  comprise conveyor belts  10 ,  11  and  12  for windrowing. The latter are guided on rollers  13  that are supported by support frames  14  provided with wheels  15  and  16 . These rollers  13  may be driven in rotation by means of hydraulic motors  17  in order to move the conveyor belts  10 ,  11  and  12  to the right or to the left. 
   The gathering and windrowing devices  7 ,  8  and  9  also comprise pick-ups  18 ,  19  and  20  to gather the products lying on the ground. The latter are situated in front of the conveyor belts  10 ,  11 ,  12  and are attached to the support frames  14 . Each pick-up  18 ,  19 ,  20  has rake tines  21  that are driven in rotation about a horizontal axis  22  in order to gather the forage lying on the ground and place it on the corresponding conveyor belt  10 ,  11  or  12 . This drive may be provided by means of a hydraulic motor not shown. 
   Said drive of the conveyor belts  10 ,  11  and  12  and of the pick-ups  18 ,  19 ,  20  may also be provided by mechanical means connected to a power take-off shaft of the tractor. 
   The central gathering and windrowing device  7  is connected to the main frame  1  by means of a lifting mechanism  23 . The latter consists of hydraulic cylinders  24  and levers  25 . The latter are articulated on said device  7  and on the main frame  1  and are arranged in the shape of parallelograms. The hydraulic cylinders  24  are connected to the frame  1  and act on the levers  25  so as to move the central gathering and windrowing device  7  up and down. 
   Each side gathering and windrowing device  8 ,  9  is connected to a support arm  26 ,  27  which extends laterally relative to the main frame  1 . As emerges in particular from  FIGS. 1 and 5 , each side support arm  26 ,  27  is articulated relative to the frame  1  on a substantially vertical axis  28 ,  29 . It can be folded about this axis  28 ,  29  at an angle of approximately 90° forward for transport, by means of a hydraulic cylinder  30 ,  31  that is situated between the frame  1  and the corresponding support arm  26 ,  27 . 
   Each side gathering and windrowing device  8 ,  9  is articulated on its support arm  26 ,  27  by means of an axis  32 ,  33  that is substantially horizontal and substantially perpendicular to the direction of travel A in the working position. Each axis  32 ,  33  is situated above the corresponding support arm  26 ,  27 . Each one is guided into lugs  34  that are attached to the top face of said support arm  26 ,  27 . Finally, each side gathering and windrowing device  8 ,  9  comprises, on its rear side, bent lugs  35  that are articulated on these axes  32  and  33 . 
   Each side gathering and windrowing device  8 ,  9  can be moved about its axis of articulation  32 ,  33  with the support arm  26 ,  27  by means of a hydraulic cylinder  36  that is situated beneath said device  8 ,  9 . Said hydraulic cylinder  36  is connected to the corresponding frame  14  and support arm  26 ,  27  (see  FIGS. 2 and 3 ). 
   The substantially vertical axis of articulation  28 ,  29  of each support arm  26 ,  27  is situated behind the corresponding side gathering and windrowing device  8 ,  9  and in the vicinity of its end closest to the central gathering and windrowing device  7 . Each of said axes of articulation  28 ,  29  is housed in the top and bottom walls of a side beam  37 ,  38  of the main frame  1  (see  FIGS. 1 and 5 ). The hydraulic cylinders  30 ,  31  provided to fold the support arms  26 ,  27  about the axes of articulation  28 ,  29  are advantageously housed in said side beams  37 ,  38 . They are articulated at one of their ends on one of the walls of this beam  37 ,  38  and at their other end on the corresponding support arm  26 ,  27 . Each side beam  37 ,  38  comprises a pivot axis  39 ,  40  that is substantially horizontal and directed in the direction of travel A. This axis allows each side gathering and windrowing device  8 ,  9  and the corresponding support arm  26 ,  27  to move heightwise for example to follow the ground unevennesses. A hydraulic cylinder  41 ,  42  may be associated with each side beam  37 ,  38  in order to be able to lift the corresponding gathering and windrowing device  8 ,  9  if there is a larger obstacle to pass. 
   At the rear of the conveyor belts  10 ,  11  and  12  are arranged deflectors  43 ,  44  and  45  for the guidance of the products. These deflectors  43 ,  44  and  45  are articulated on the frames  14  and can be moved from a position substantially perpendicular to the conveyor belts  10 ,  11  and  12  in work into a position substantially parallel to said conveyor belts in transport. 
   The main frame  1  comprises mechanisms  46  and  47  for the immobilization of the side gathering and windrowing devices  8  and  9  in the transport position. As is shown in  FIG. 4 , these mechanisms  46  and  47  extend either side of the central beam  2  and connect the side gathering and windrowing devices  8  and  9  to this central beam  2  in transport and for setting down. Each of these mechanisms  46  and  47  consists of an arm  48  that is rigidly fastened to the central beam  2  of the frame  1  and on which a hook  49  is articulated by means of an axis  50  (see  FIGS. 6 and 7 ). This hook  49  hooks onto a shackle  51  provided on the corresponding side gathering and windrowing device  8 ,  9  in order to immobilize the latter. For this purpose, the hook  49  may be moved about the axis  50  by a system of levers  52 ,  53  controlled by means of a hydraulic cylinder  54 . The system of levers  52 ,  53  forms an articulation of the knuckle-joint type which is self-locked in the position of immobilization of the side gathering and windrowing devices  8  and  9 . It comprises a first lever  52  that is bent and a second straight lever  53  that are articulated with one another by means of an axis  55 . Said straight lever  53  is also articulated on the hook  49  by means of an axis  56 . The bent lever  52  is articulated on the corresponding arm  48  by means of an axis  57  and on the rod of the hydraulic cylinder  54  by means of an axis  58 . The body of said hydraulic cylinder  54  is, for its part, articulated on the corresponding arm  48  by means of an axis  59 . 
     FIG. 7  shows that the arrangement of the axes of articulation  55 ,  56  and  57  of the levers  52  and  53  is such that, when the immobilization device is in the locked position, the axis of articulation  55  between the two levers  52  and  53  is situated beneath a plane P passing through the other two axes of articulation  56  and  57  of said levers  52  and  53 . In this position, the hook  49  is held in the locked position by the levers  52  and  53 , independently of the action of the hydraulic cylinder  54 . In the unlocked position ( FIG. 6 ), the axis of articulation  55  between the two levers  52  and  53  is situated above the plane P. This position is obtained by pulling on the bent lever  52  by means of the hydraulic cylinder  54  in order to make it pivot on its axis of articulation  57 . The axis of articulation  55  and the second lever  53  then move upward and drive the hook  49  that they cause to rotate about its axis of articulation  50  so that its end disengages downward. The return to the locked position is achieved by exerting a pressure on the first lever  52  with the hydraulic cylinder  54  so that the levers  52  and  53  move in a manner converse to that described hereinabove. 
   The hydraulic cylinders  24 ,  30 ,  31 ,  36 ,  41 ,  42  and  54  of the machine are advantageously connected to the hydraulic system of the tractor by means of pipes and may be controlled from the latter. 
   During work, the machine is coupled to a tractor which drives it and moves it in the direction of travel A. The central gathering and windrowing device  7  is lowered by means of the lifting mechanism  23  so that its wheels  15  and  16  move over the ground. The support arms  26  and  27  and the side gathering and windrowing devices  8  and  9  extend either side of the central beam  2 . The wheels  15  and  16  of said devices  8  and  9  also move over the ground. The three gathering and windrowing devices  7 ,  8  and  9  are then substantially in line and extend substantially perpendicular to the direction of travel A. Their pick-ups  18 ,  19  and  20  are driven so that the rake tines  21  gather the forage lying on the ground and deposit it on the conveyor belts  10 ,  11  and  12 . The latter are driven so that they move this forage laterally, transmitting it from one to the other without it returning to the ground and depositing it on one of the sides of the machine in the form of a large volume windrow. The direction of displacement of the conveyor belts  10 ,  11  and  12  may be chosen according to the side on which the forage is to be deposited. 
   It is also possible to raise the central gathering and windrowing device  7  by means of the lifting mechanism  23  and to work only with the side devices  8  and  9 . Their conveyor belts  11  and  12  may then be driven in the reverse direction so that they move the forage toward the middle of the machine to form a central windrow. 
   For transport, the central gathering and windrowing device  7  is raised with the lifting mechanism  23  in order to move it away from the ground. Then the side gathering and windrowing devices  8  and  9  are pivoted by means of hydraulic cylinders  36  about their axes of articulation  32  and  33  to a substantially vertical position. They are then situated substantially above the support arms  26  and  27 . The latter are then folded forward, by means of the hydraulic cylinders  30  and  31 , to a position in which they are directed in the direction of travel A. The side gathering and windrowing devices  8  and  9  are then substantially parallel to the central beam  2  of the frame  1  and are situated on either side of the central gathering and windrowing device  7 . The width of the machine is thus considerably reduced and its ground clearance is sufficient for displacements on tracks and roads ( FIGS. 4 and 5 ). 
   In this transport position, the side gathering and windrowing devices  8  and  9  are locked relative to the frame  1  by means of the immobilization mechanisms  46  and  47 . Before these side devices  8  and  9  reach the transport position, the hooks  49  are held down in the unlocked position by the levers  52  and  53  and the hydraulic cylinders  54  that are in the closed position (see  FIG. 6 ). When said side devices  8  and  9  reach the vicinity of the arms  48 , the hydraulic cylinders  54  are actuated so that they extend. As a result, they push the levers  52  and  53  downward so that the latter move the hooks  49  upward so that they hook onto the yokes  51  provided on the side devices  8  and  9  (see  FIG. 7 ). Thanks to the arrangement of the levers  52  and  53  in this position, the latter hold the hooks  49  in the locked position even if the hydraulic pressure were to diminish in the cylinders  54  due to a leak for example. 
   For the return to the working position, the hydraulic cylinders  54  are operated so that they disengage the hooks  49  downward. Then, the support arms  26  and  27  may be pivoted outward and rearward by the hydraulic cylinders  30  and  31  and the gathering and windrowing devices  8  and  9  may be lowered to the ground by means of the hydraulic cylinders  36 . The actions of these various hydraulic cylinders  24 ,  30 ,  31 ,  36  and  54  may be initiated automatically with the aid of control valves controlled from detectors of the positions of the support arms  26  and  27  and of the gathering and windrowing devices  7 ,  8  and  9 . 
   It is evident that the invention is not limited to the embodiments described and shown in the appended drawings. Modifications remain still possible, particularly as concerns the constitution of the various elements or by substitution of technical equivalents, without, for all that, departing from the field of protection.