Mower equipped with a cutting bar
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to a mower equipped with a cutting bar and having cutting elements extending above a housing, each of the cutting elements being guided and driven in rotation around an axis directed upward by a guiding and driving bearing which includes a casing centered in a corresponding bore made in the upper part of the housing, a guiding bearing mounted in said casing and a shaft guided in said casing with the help of the guiding bearing, said shaft being equipped at its upper end with a fastening part for fastening a corresponding cutting element and at its lower end with a second gear extending inside the housing and meshing with at least one first gear also housed inside said housing, said second gear having an outside diameter which is less than the diameter of the corresponding bore made in the upper part of the housing, each of said guiding and driving bearings being fastened to the upper part of the housing by bolts the shanks of which extend out of the upper part of the housing and nuts screwed on said shanks, said housing being formed by said upper part and a corresponding lower part assembled in a removable way by assembly members. 
     Discussion of the Background 
     A mower is known wherein the bolts fastening the guiding and driving bearings to the upper part of the housing, have their heads extending inside said housing and their shanks extending upward while passing through corresponding holes provided in said upper part. Since the bolt is not held in rotation, in order to change a guiding and driving bearing, it is necessary to remove the lower part of the housing to lock the rotation of the bolts, to be able to loosen and then tighten the nuts screwed on the shank of the corresponding bolts. It is understood that this operation can be performed only in a workshop, especially since in general the housing contains a lubricant in which the gears driving the cutting elements in rotation are bathed. This operation will therefore immobilize the machine for a relatively long time at a time precisely when the user has a pressing need for it. 
     It can then be conceived to fasten the bolts rigidly to the upper part of the housing by welding, for example. This solution, however, is not good for several reasons. A first reason is that the sheet metal constituting the upper part of the housing can be deformed during welding, so that after welding, the shanks of the bolts are not parallel to one another, which will pose problems in having them pass through the passage holes made in the casing of the corresponding guiding and driving bearing. A second reason is that, considering the length of the upper parts of the housing, their manipulation for welding of the bolts is not easy. A third reason is that the shanks of the bolts which extend outside the upper part of the housing can be seriously damaged at the building site or at the dealer&#39;s location during storage or handling of the upper part before mounting. In this case, it will be impossible to screw the corresponding nuts on the damaged shanks. 
     SUMMARY OF THE INVENTION 
     The object of this invention is to propose a solution that does not have the drawbacks of the prior devices. 
     For this purpose, the mower according to the invention is characterized by the fact that each bolt fastening the guiding and driving bearings to the upper part of the housing is fastened to a holding element which holds said bolt approximately in the appropriate or desired position and which prevents rotation of said bolt during tightening or loosening of the corresponding nut, said bolt and its holding element constituting a removable assembly. 
     Thanks to this characteristic, the bolts being used to fasten the guiding and driving bearings to the upper part of the housing will be mounted only at the moment of mounting the cutting bar. Consequently, these bolts cannot be damaged during storage or handling of the upper parts of the housing. It is then possible to loosen and tighten the nuts screwed on these bolts without it being necessary to remove the lower part of the housing because the holding element prevents rotation of the corresponding bolt. In addition, the holding element holds the corresponding bolt approximately in its appropriate position so that the bolt is not in danger of falling into the housing when the corresponding guiding and driving bearing has been removed. Consequently, it is possible for the user to himself change a defective guiding and driving bearing without the machine having to be taken to a workshop so that in case of breakdown of a guiding and driving bearing, the machine will be able to be repaired very quickly. Considering the fact that the bolt and its holding element constitute a removable assembly, it will be possible to change this assembly if the bolt were to become defective. 
     According to an additional characteristic of the invention, the holding element holds the corresponding bolt approximately in the desired position after mounting of the lower part of the housing on the upper part of said housing. This characteristic particularly allows for the advantage of not increasing the thickness of the housing, although the holding element extends inside the housing. 
     According to a further characteristic, each holding element is equipped with several bolts. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views and wherein: 
     FIG. 1 represents a top view of a mower according to the present invention; 
     FIG. 2 represents a top view on a larger scale of the cutting bar of the mower of FIG. 1 without the cutting elements which have been shown only in dot-and-dash lines; 
     FIG. 3 represents on a larger scale a view in section taken along line III--III (FIG. 1) of the cutting bar; 
     FIG. 4 represents a view in section along line IV--IV defined in FIG. 2; and 
     FIG. 5 represents a view in perspective of a holding element equipped with two bolts. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A mower 1 is shown in FIG. 1 which comprises a cutting bar 2 extending in a known manner under a protective device 3. In this FIG., the device making it possible to connect said cutting bar 2 to a tractor vehicle has not been shown. These devices are actually within the scope of a person skilled in the art. 
     Cutting bar 2 comprises, as a nonlimiting example, six cutting elements 4, 5 each rotating around an axis 450 (see FIGS. 2 and 3) directed upward, for example in the directions 6, 7. Each cutting element 4, 5 is equipped with two blades 8 and extends above a housing 9 in which it is guided in rotation and which contains driving elements 10 (see FIGS. 2 and 3) intended to drive said cutting elements 4, 5 in rotation. 
     In FIGS. 2 and 3, it can be seen that housing 9 is formed by an upper part 11 and a lower part 12 which are connected to one another by assembly members 13. After assembly, both parts 11, 12 define an approximately parallelepiped space 14 which contains the driving elements 10. These driving elements 10, in the example shown, consist of a series of cylindrical gears 15 and intermediate cylindrical gears 16 meshing with one another and rotating in lubricant also housing 9. Each gear 15 is connected at lower end 17 of a shaft 18 by splines 19 and by a nut 20. At its upper end 21, shaft 18 is connected to a fastening part 22. This fastening part 22 makes it possible to fasten the corresponding cutting element 4, 5 to shaft 18 by bolts 23. 
     Shaft 18 is guided in rotation in a guiding bearing 24 which, in the example shown, consists of a two-row, angular-contact ball bearing. This guiding bearing 24 is itself mounted in a casing 25 and is connected at this location in translation by a shoulder 26 and a circlip 27. Casing 25 is centered in a corresponding bore 28 made in the upper part 11 of housing 9 and is fastened to said upper part 11 by assembly elements 29. The diameter of bore 28 is greater than the outside diameter of corresponding gear 15, but is smaller than the outside diameter of flange 250 of casing 25. 
     The unit, which includes a casing 25, guiding bearing 24, circlip 27 being used to connect this guiding bearing 24 to casing 25, shaft 18, fastening part 22, gear 15 and nut 20 forms a guiding and driving bearing 30. Guiding and driving bearing 30 can be mounted or removed from housing 9 through the top since the outside diameter of gear 15 is smaller than the diameter of corresponding bore 28. 
     As can be seen in FIGS. 2 to 5, assembly elements 29 that are used to fasten a casing 25 to upper part 11 of housing 9 comprise, in particular, bolts 31 and nuts 32. In the example shown, each casing 25 is fastened by four bolt 31-nut 32 assemblies. Each bolt 31 has a head 33 which extends inside the parallelepiped space 14 and a shank 34 which extends out of upper part 11 of housing 9 by passing through a corresponding hole 35 provided for this purpose in upper part 11. To hold bolts 31 in their appropriate position, they are fastened in the example shown, by welding) to holding elements 36. In this example, each holding element 36 is equipped with two bolts 31 so that for each casing 25, there are two holding elements 36. Each holding element 36 consists of a bracket wherein one wing 37 thereof extends approximately horizontally and supports bolts 31 and the other wing 38 extends approximately vertically between upper part 11 and lower part 12 of housing 9. In FIGS. 3 and 4, it can be seen that the height of holding element 36, i.e., in the example shown, the length of vertical wing 38, is approximately equal to the inside thickness of housing 9. As stated, each holding element 36 is equipped with two bolts 31 and the fastening of each guiding and driving bearing 30 therefore requires two holding element 36-bolt 31 assemblies. In FIG. 2, it can be seen that these holding elements 36 extend approximately parallel to the longitudinal axis of housing 9, to make possible the meshing between corresponding gear 15 and neighboring intermediate gears 16. In addition, it is seen in FIGS. 2 and 5 that horizontal wing 37 of a holding element 36 comprises a circular recess 39 centered on the axis of rotation 450 of corresponding gear 15 and with a radius slightly larger than the radius of said gear 15. 
     Finally, in FIG. 4, it can again be seen that at the location where shank 34 of a bolt 31 extends out of upper part 11 of housing 9, shank 34 has an approximately semicircular groove 340 in which an O-ring 341 is mounted. At the same time, corresponding passage hole 251 provided in flange 250 of corresponding casing 25, includes, at the position where it extends out of the face of said flange 250 intended to come in contact with upper part 11 of housing 9, a beveled portion 252. Thus, during mounting of guiding and driving bearing 30 on upper part 11 of housing 9, O-ring 341 fills the space created between groove 340 and corresponding beveled portion 252 and thereby obtains a perfect seal preventing any leakage of lubricant contained in housing 9. 
     Mounting of cutting bar 2 which has just been described is performed in the following manner: the upper part 11 of housing 9 is placed upside down; the various intermediate gears 16 are mounted; the holding element 36-bolt 31 assemblies are put in place, i.e., shanks 34 of bolts 31 are introduced in corresponding holes 35 made in upper part 11; lower part 12 is placed on upper part 11 and these two parts are assembled with assembly members 13; and then the unit is turned over so that upper part 11 is now on top. In this position, bolts 31 will be held approximately in their desired position by corresponding holding elements 36, since said holding elements 36 have a height approximately equal to the inside thickness of housing 9. Then, previously preassembled guiding and driving bearings 30 are mounted and are fastened with nuts 32 that are screwed on shanks 34 of corresponding bolts 31. This is possible because during the tightening of a nut 32 on shank 34 of a bolt 31, the latter is prevented from rotation by corresponding holding element 36 and by the other bolt 31 with which this holding element 36 is also equipped. Finally, cutting elements 4, 5 are fastened to corresponding guiding and driving bearings 30 with bolts 23. 
     If during operation a guiding and driving bearing 30 becomes defective, the user will be able to himself change it very quickly without it being necessary to remove entirely cutting bar 2. The mower will therefore be able to be repaired in the field itself and at less cost. 
     To do this, it will actually suffice to remove cutting element 4, 5 corresponding to the defective guiding and driving bearing 30; remove the nuts 32; take out the defective guiding and driving bearing 30; mount a new guiding and driving bearing 30; screw the nuts 32 again on shanks 34 of corresponding bolts 31; and mount the corresponding cutting element 4, 5. 
     In FIG. 2, there can also be seen the shape of fastening part 22 of each guiding and driving bearing 30 making possible the fastening of corresponding cutting element 4, 5. This shape is such that nuts 32 being used for the fastening of a guiding and driving bearing 30 to upper part 11 of housing 9, are easily accessible from the top. This makes possible the use of motor-driven screwdrivers during mounting of the cutting bar 2 and, therefore, contributes to reducing the mounting costs. In the example shown, fastening part 22 comprises four flat surfaces 40 which impart to said fastening part 22 in a top view an approximately square general shape. This special shape makes possible simultaneous access to four nuts 32 so that it will be possible to use special screwdrivers with four tightening heads for a simultaneous tightening of four nuts 32. 
     Cutting bar 2 which has just been described above can be used in a standard mower, in a mower-windrower or in a mower conditioner. 
     Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.