Abstract:
A detachable front-loader comprising a loader assembly consisting of two arms ( 1 ) joined by one or more transverse members ( 2,3 ) as shown in FIG.  1.  Each arm ( 1 ) is provided with a supporting device comprising a pivotable support foot ( 9 ) and a telescopic strut ( 10 ). Each support device is movable between a non-operational position wherein the support foot ( 9 ) rests against a respective arm ( 1 ), and an operational position. The foot ( 9 ) is retained in the operational position by locking the telescopic strut ( 10 ) in an extended state. Opposing ends ( 15,16 ) of the strut are provided with screw threads ( 15   a   ,16   a ) which are connected to threaded members ( 13,14 ) pivotally located on the foot ( 9 ) and the arm ( 1 ).

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a detachable front-loader with a loader assembly consisting of two arms joined by one or more transverse members, the arms being assigned a supporting device having a supporting foot attached to the terminal region at the tool-end of the arm, and the device being pivotable between a non-operational position and an operational position, whereby the device is retained on the assembly when in the non-operational position and in the operational position the position relative to the arms is determined by means of a supporting strut acting between the arms and supporting foot. 
     A known device for supporting a detachable front-loader consists of a supporting foot which is retained against the loader arm by means of a locking bolt when the foot is pivoted up into a non-operation position. In order to detach the front loader, the supporting foot is pivoted downwards after removal of the locking bolt and locked in one of several operational positions. The operational positions are predetermined by holes in the supporting foot, in which the above-mentioned locking bolt can be inserted. The actual detaching procedure is effected with the aid of the hydraulic system of the vehicle by tipping the loading tool, eg a shovel, of the front loader which has been positioned beforehand on the ground. 
     The disadvantage of this arrangement is that, if the hydraulic system fails, the front-loader cannot be dismounted from the vehicle. In addition, because the holes are spaced at a relatively large distance apart from one another, it is not possible to adjust the supporting feet on uneven terrain and the supporting struts in particular cannot be adjusted under load. Consequently, the supporting feet cannot be braced firmly on the ground immediately before the front loader is dismounted. This means that every time the front loader is dismounted from the vehicle, the situation is critical in that any lateral movements or rocking of the front-loader might cause damage to the vehicle. 
     SUMMARY OF THE INVENTION 
     The objective of the invention is to provide a detachable front loader which can be mounted and dismounted in a straightforward manner, by manipulation of the supporting device and without risk of damaging the vehicle. 
     Accordingly there is provided a detachable front-loader with a loader assembly, consisting of two arms joined by one or more transverse members, each of the arms being provided with a supporting device having a supporting foot attached to the terminal region at the tool-end of the respective arm, the foot being pivotable between a non-operational position and an operational position, wherein each foot is retained on a respective arm in the non-operational position and in the operational position, the position of each foot relative to the respective arm is determined by a respective supporting strut acting between the arm and the supporting foot, characterised in that the struts remain pivotally joined between the linking arm and the supporting foot and the effective length of the supporting struts can be adjusted under load. 
     The objective is achieved owing to the fact that the effective length of the supporting strut under load can be continuously adjusted, and the supporting struts remain pivotally joined to the linking arm and the supporting foot at the end face. This means that once they have been pivoted into the operational position, the two supporting feet can be supported on the ground with the same force by individually adjusting the supporting struts. When the front-loader is then uncoupled from the vehicle, which can be done either with the aid of the hydraulic system of the vehicle or by manually adjusting the length of the supporting struts, the front-loader will not be susceptible to uncontrolled movements which might cause damage to the vehicle. 
     For practical purposes, one embodiment of the invention has the following features: 
     a supporting strut consisting of two tubes telescopically inserted one inside the other, each provided with threading at its free end, one being a right-hand-thread and the other a left-hand-thread, 
     the threads co-operate with matching threads of threaded bolts which are coupled with the linking arm and the supporting foot, and 
     the tubes can be made to rest in a predetermined position so that they do not move relative to one another by means of a locking bolts, which is inserted through transverse bores of the tubes when they are flush with one another. 
     In the case of one particularly practical embodiment of the invention, which produces very little in the way of compressive forces in the supporting strut and allows the length of the supporting strut to be manually adjusted, when the front-loader is parked, one end of the supporting strut is placed more or less at the centre of the supporting foot whilst the other end is attached to the loader arm in such a way that, if viewed from the side, it is more or less aligned with the centre of gravity of the loader arm. 
     Other advantageous features of the invention are set out in the dependent claims. A hydraulic cylinder can be provided as a supporting strut, which will enable the front-loader to be mounted and dismantled from the driver&#39;s cab. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a parked front-loader and a vehicle specifically designed for mounting the front-loader; 
     FIG. 2 is a detail of the front-loader of FIG. 1, and 
     FIG. 3 is a detail of the loader arm with a supporting strut pivoted into the non-operational position. 
    
    
     DETAILED DESCRIPTION 
     The front loader has two lateral linking arms  1  spaced apart from one another, which are joined to one another by means of two tubular members  2 ,  3  to form a loader arm. At the proximal region of the loader arm at the vehicle end, the linking arms  1  are attached by means of an articulated joint  4  to a frame  5 , which can be mounted in matching holders  6  on a carrier vehicle  7 . 
     At the distal region of the loader remote from the vehicle  7 , a shovel  8  is attached, which is retained parallel with the ground by means of a parallelogram rod-linkage, not illustrated, regardless of the position of the loader arm. The shovel  8  can be pivoted by means of an adjusting cylinder. 
     Each linking arm  1  is provided with a supporting assembly to support the front loader when it is detached from the carrier vehicle  7 . The assembly comprises a supporting foot  9  and a supporting strut  10 . The supporting foot  9  is attached to the inner side of the linking arm  1  underneath the lower tubular member  2  by means of an articulated joint  11  in such a way that in the non-operational position, which is illustrated in FIG. 3, it lies almost completely within the contour of the loader arm  1 . The supporting foot  9  has a unshaped cross-section, with side walls  9   a ,  9   b  Located in each side in walls  9   a ,  9   b , approximately midway between the articulated joint  11  and the end  9   c  which, in use, lies on the ground, is an ‘L’ shaped slot. The slot comprises a larger hole portion  9   e  running substantially parallel to the longitudinal direction of the foot  9 , and a shorter hole portion  9   d  running at right angles to the longitudinal direction of the foot  9 . Inserted in the slot  9  is a bolt  12  provided with a head  12   a  at both ends, on which a threaded bolt  13  with a left-hand thread is pivotably mounted. 
     A further threaded bolt  14  with a right-hand thread is pivotally mounted on the upper tubular member  3 . The strut  10  comprises two tubes  15 ,  16  provided telescopically one inside the other. The outer end of each tube  15 ,  16  has an internal thread l 5   a ,  16   a  which corresponds to the threads on the bolts  13 ,  14 . The strut  10 , in use, supports the foot  9  in the operational position shown in FIG.  1 . In this position, the two tubes  15 ,  16  are located in such a position relative to one another that a transverse bore  15   b ,  16   b  provided in each of the tubes  15 ,  16  can be brought into alignment by rotating one of the tubes relative to the other. With the bores  15   b ,  15   c  aligned the tubes  15 ,  16  can be secured by manually inserting a locking bolt  17 , and thus are prevented from rotating or sliding relative to one another. The diameter of the tubes  14 ,  15  is less than the width between the side walls  9   a ,  9   b  so that the supporting strut  10  is able to lie within the cross-section thereof when the supporting foot  9  is pivoted into the non-operational position. To ensure that the supporting foot  9  remains in this position and does not inadvertently fall out into the operational position, the side walls  9   a ,  9   b  are each provided with a hole  9   f , into which the locking bolt  17  can be inserted, such that it rests behind the outer tube  15 . In order to prevent undesirable movements and noises, a stop  18  made from a rubber elastic material is arranged between the base  9   g  of the supporting foot  9  and the supporting strut  10 , which pushes the supporting strut  10  against the locking bolt  17 . 
     The elongated hole portions  9   e  extending the longitudinal direction of the supporting foot  9  allow the length of the supporting strut  10  to be selected, in use, so that it is more or less aligned with the centre of gravity S of the loader arm when the front-loader is parked. This arrangement minimises the bending forces experienced, in use, by the supporting strut  10 . 
     A short extension-piece  9   h  of the supporting foot  9  beyond the articulated joint  11  is designed to act as a stop which limits the range of the downward pivoting movement of the supporting foot  9  by bearing against the tube member  2  This serves to prevent the supporting foot  9  from pivoting enough to cause the tubes  15 ,  16  to slide apart from one another. The extreme position of the supporting foot is illustrated in FIG. 2 by the dot-and-dash lines. 
     The procedure for dismantling a front-loader will be described below. 
     Initially, the front-loader is secured to the vehicle and both supporting feet  9  are pivoted into the non-operational position, as can be seen in FIG.  3 . The tubes  15 ,  16  are fully screwed down on to the relevant threads of the threaded bolts  13 ,  14  so that the supporting strut  10  assumes the position in which it is at its smallest possible, length, with the bolt  12  being located at the end of the elongated hole portions  9   e  closest the joint  11 . In this position, the supporting strut  10  is retained by means of the locking bolt  17  inserted into the holes  9   f  in the side walls of the supporting foot  9 . 
     Once the locking bolt  17  has been removed, the supporting foot  9  can be pivoted down into the operational position so that the outer tube  15  slides downwards on the innertube  16 , and the bolt  12  slides to the other end of the elongated hole portion  9   e . The pivoting movement of the foot  9  is stopped before the tubes  15 ,  16  can slide out from one another because the extension  9   h  on the tube  2  insert. 
     The loader shovel  8  is then set down with its front edge on the ground by lowering the loader arm onto the ground G. During this procedure, the end  9   c  of the supporting foot  9  contacts the ground and slides to the position illustrated in FIG.  2 . As soon as the transverse bores  15   b  and  16   b  are positioned at the same height, the two tubes are joined to one another by inserting the locking bolt  17 . The supporting foot  9  is able to pivot a little further because the bolt  12  runs in the holes  9   d  and is retained in this position. The tubes  15 ,  16  can then be manually rotated on the locking bolt  17  and the supporting feet  9  braced firmly against the ground, thereby accommodating any unevenness in the ground surface. If the loader shovel  8  is now tipped so that its entire surface lies on the ground, this action will cause the frame  5  of the front loader to lift out of the holders  6  at the vehicle end, as illustrated in FIG.  1 . After uncoupling the hydraulic lines connecting the vehicle to the front-loader, the vehicle can be taken out of the frame  5 . 
     If necessary, eg if the hydraulic system of the carrier vehicle  7  fails, the frame  5  can be separate from the holders  6  by manually rotating the tubes  15 ,  16  further in the direction in which the supporting strut  10  will be lengthened.