Abstract:
A gearbox, particularly for an automotive vehicle with a telescopic load-carrying arm, is adapted to transmit directly or indirectly the drive movement of an internal combustion motor (M) with at least one front or rear axle provided with driven wheels. This gearbox includes a casing ( 13 ) containing an angled transmission ( 15 ) arranged to transmit the movement of the output shaft ( 17 ) of the motor, to a drive shaft ( 9  or  10 ) of the front or rear axle, or both. The gearbox further comprises a power takeoff through shaft ( 16 ) arranged to drive a pump that generates hydraulic or hydrostatic energy.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based on the disclosure of French application 00.12861 filed in France on Oct. 9, 2000, the entirety of which application is hereby expressly incorporated by reference. 
     FIELD OF THE INVENTION 
     The invention relates to gearboxes, particularly for automotive vehicles with telescopic load-bearing arms. 
     The invention also relates to an automotive vehicle with a telescopic load-bearing arm provided with a gearbox according to the invention. 
     BACKGROUND OF THE INVENTION 
     Automotive vehicles with telescopic load-bearing arms are known, produced and sold by the MANITOU BF Company in France, in which a diesel motor is oriented transversely to the longitudinal axis of the machine. 
     The diesel motor drives an angled transmission, of which an output drives a gearbox oriented longitudinally and disposed substantially in a central position and of which another output continuously drives a hydraulic pump upon startup of the motor. 
     These machines are generally satisfactory, but have a large number of mechanical members (resilient coupling, cardan transmission, angled transmission, torque converter, gearbox), of which certain ones are mounted in individual casings before being assembled together. 
     This technique results in a substantial size of the assembly produced and a costly fabrication of the mechanical transmission means of these machines. 
     SUMMARY OF THE INVENTION 
     The invention has for its object to overcome the drawbacks of the prior art, by providing a new gearbox, adapted particularly for new automotive vehicles with a telescopic load-carrying arm, of simple and economical construction and of reduced size. 
     The invention has for its object a gearbox, particularly for an automotive vehicle with a telescopic load-carrying arm, adapted to transmit directly or indirectly the drive movement of a transversely oriented internal combustion engine, to at least one front or rear axle having drive wheels, by means of at least one longitudinally oriented shaft, characterized in that the casing of the gearbox contains an angled transmission, whose transversely oriented input is adapted to be driven by a clutch means, and whose longitudinally oriented output defines a first shaft line of the gearbox. 
     According to other advantageous characteristics of the invention: 
     the gearbox comprises moreover a through power takeoff shaft arranged to drive a pump generating hydraulic or hydrostatic energy 
     the angled transmission comprises a double conical pinion: a forward drive pinion and a rear drive pinion, with at least one associated clutch, 
     the gearbox is driven by a torque converter connected to the output of the internal combustion motor by constituting the first drive member from the gearbox, whilst the angled transmission is the second driving member secured to the turbine of the converter. 
     the casing of the gearbox contains at least three parallel shaft lines: a first shaft line corresponding to the angled transmission, a second intermediate shaft for transmission between the first shaft line and a third shaft line, this third shaft line corresponding to the shaft (or shafts) for driving the front or rear axle (or front or rear drive axles), 
     the first shaft line corresponding to the angled transmission comprises a double conical pinion engaging with a conical pinion adapted to be driven by the output shaft of the motor, and a double clutch for selectively driving a toothed forward drive wheel or a toothed rearward drive wheel, and these two toothed front and rear drive wheels engaging continuously with toothed wheels of the second intermediate transmission shaft, 
     the second shaft line comprises several toothed wheels for transmission of movement imparted by the first shaft line to the corresponding toothed wheels of the third shaft line with which they are continuously in engagement, 
     the corresponding toothed wheels of the third shaft line are mounted freely in rotation on the third shaft, and are adapted to drive this third shaft under the action of clutch or toothed means, 
     the third shaft line moreover comprises a toothed wheel mounted securely on the third shaft and engaging with a toothed wheel disengageable from the second shaft line, so as to provide a number of forward drive speeds that is greater than the number of rearward drive speeds, 
     the third shaft line comprises two shaft output adapted to drive simultaneously a front drive axle and a rear drive axle of an automotive vehicle, particularly a vehicle with a telescopic load-carrying arm. 
     The invention also has for its object an automotive vehicle with a telescopic load-carrying arm, of the type comprising two front and rear axles provided with wheels, and an internal combustion engine driving a gearbox. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood from the description which follows, given by way of non-limiting example, with reference to the accompanying drawings, in which: 
     FIG. 1 shows schematically in a view from above the kinematic arrangement of one embodiment of automotive vehicle according to the invention. 
     FIG. 2 shows schematically a side view of a gearbox according to the invention. 
     FIG. 3 shows schematically a kinematic chain of a first embodiment of gearbox according to the invention. 
     FIG. 4 shows schematically a kinematic chain of a second embodiment of gearbox according to the invention. 
     FIG. 5 represents schematically a kinematic chain of a third embodiment of gearbox according to the invention. 
     FIG. 6 shows schematically a perspective view of an assembly comprising a gearbox according to the invention shown with the casing partially broken away. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1, an embodiment of a vehicle according to the invention comprises a kinematic arrangement with a front axle  1  and a rear axle  2 . Front axle  1  is a self-blocking differential axle with limited sliding, driving two front driven and steering wheels  3  and  4 . The control of the front axle is a hydrostatic control with a central double-acting jack  5 . 
     The rear axle  2  is a self-blocking differential axle with limited sliding to drive and orient two driven and steerable rear wheels  6  and  7 . 
     The control of the rear axle is also a hydrostatic control with a central double-acting jack  8 . 
     The drive of the front axle  1  is ensured by means of a cardan shaft  9 , whilst the drive of the rear axle  2  is ensured by means of a cardan shaft  10 . The cardan shafts  9  and  10  are connected to two corresponding power outputs of a gearbox  12  designed such that the cardan shafts  9  and  10  will be driven simultaneously at the same speed when the vehicle moves and such that the cardan shafts  9  and  10  will be simultaneously stopped when the vehicle is stopped. 
     The gearbox  12  comprises a casing  13  surrounding a torque converter  14  or equivalent clutch with a hollow shaft, adapted to drive an angled transmission  15  with a double conical pinion. 
     The converter  14  with a hollow shaft and the angled transmission  15  are traversed by a central shaft  16  for power takeoff, secured to the output shaft  17  of the motor M, or to the inertial flywheel of the internal combustion engine M so as continuously to drive the power takeoff shaft  16  upon starting up the motor M. The power takeoff shaft  16  is preferably adapted to drive a pump generating hydraulic or hydrostatic energy, not shown and external to the casing  13  of the gearbox  12 . 
     Preferably, the converter  14  with a hollow shaft or equivalent clutch is connected to the output drive of the internal combustion motor M and constitutes the first member driving the gearbox  12 , whilst the angled transmission  15  is the second driving member secured to the turbine of the converter  14  with a hollow shaft and integrated into the casing  13  of the gearbox  12 . 
     The angled transmission  15  with double conical pinion comprises a forward drive pinion  15   a  with an associated clutch  18   a  and a reverse drive pinion  15   b  with an associated clutch  18   b.    
     The casing  13  of the gearbox  12  contains three parallel shaft lines A 1 , A 2 , A 3 . 
     The first shaft line A 1  corresponding to the angled transmission  15  comprises for forward drive: the pinion  15   a , the associated clutch  18   a  and the toothed forward drive wheel  19   a ; and for reverse drive: the pinion  15   b , the associated clutch  18   b  and the reverse drive toothed wheel  19   b.    
     The toothed wheels for forward drive  19   a  or reverse drive  19   b  continuously engage with the toothed wheels  20   a ,  20   b  of the second intermediate shaft A 2  of the transmission, which also comprises toothed wheels  21 ,  22 ,  23  fixed in rotation with the toothed wheels  20   a ,  20   b.    
     Each toothed wheel  20   a  or  21  or  22  or  23  continuously engages with the toothed wheel  30  or  31  or  32  or  33  of the third shaft line A 3  for driving the cardan shafts  9  and  10  of front and rear axles  1  and  2 . 
     The toothed wheels  30  to  33  are mounted freely in rotation on the third shaft line with the possibility of engagement or equivalent synchronous drive with the crowns  34 ,  35  mounted securely in rotation with the third shaft line, preferably mounted on grooves on the third shaft  37  with the possibility of lateral movement under the action of mechanical controls of a type known per se and not illustrated. 
     The toothed engagement of a crown  34  or  35  with one of the toothed wheels  30  to  33  thus permits selecting the forward speed or rearward speed. 
     With reference to FIGS. 2 to  4 , identical or functionally equivalent elements to FIG. 1 are indicated by the same reference numerals. 
     In FIG. 2, the casing  13  comprises flange  13   a  for mounting on the casing C of the flywheel V of the motor M (not shown). The converter  14  with a hollow shaft comprises a turbine  14   a  with a hollow shaft for driving the angled transmission  15 , a reactor  14   b , and an impeller  14   c  secured to the flywheel V of the motor M (not shown). The power takeoff shaft  16  is driven by the output shaft  17  of the motor M and passes between the pinions  15   a ,  15   b  to leave the casing  13  and to drive a hydraulic pump (not shown). 
     The three shaft lines described with reference to FIGS. 1 to  6  are schematically shown by the geometrical axes A 1 , A 2 , A 3 . 
     The reduced size of the casing  13  and of the gearbox  12  according to the invention corresponds to the mounting of the three shaft lines A 1 , A 2 , A 3  on sealed bearings of known type and does not require a more detailed description. 
     The reduction of size in the transverse direction permits obtaining a reduced distance d between the flange  13   a  and the axis A 3  of the shaft  37 , preferably comprised between 200 and 500 mm and permits mounting substantially in alignment the cardan shafts  9  and  10  and the third shaft  37 , thereby avoiding the addition of any intermediate transmission and any supplemental gearing. 
     The shaft  37  is thus preferably located, after mounting, substantially in the median longitudinal plane of the machine for which the gearbox  12  is provided. 
     FIG. 3 shows schematically a first embodiment of gearbox according to the invention adapted for an automotive vehicle of the type described with reference to FIG. 1, comprising reference numerals identical to the reference numerals of FIGS. 1 and 2. 
     In this embodiment, the casing  13  of gearbox comprises a bell  13   b  surrounding the torque converter  14  or equivalent clutch, and a sealed chamber  13   c  receiving a hydraulic liquid for lubricating the gearing and the clutches of the gearbox  12 . 
     Bell  13   b  of casing  13  of gearbox  12  is mounted on the casing C of the motor flywheel V by its flange  13   a.    
     The selection of the speed ratio results from the coaction or the reciprocal activity of the different clutch or mechanically toothed members, as indicated in the speed table in which the numeral  1  indicates the clutching activity  18   a  or  18   b , or the drive of a crown  34  or  35  and the drive axles  1  and  2  by one of the toothed wheels  30  to  33  of the shaft  34 , whilst the numeral  0  indicates the dead point of the clutch  18   a  or  18   b  or the absence of activity of a toothed wheel  30  to  33  in the free wheel condition on shaft  37 . 
     FIG. 4 shows schematically a second embodiment of gearbox according to the invention, comprising reference numerals identical to those of FIG.  2 . 
     This second embodiment differs from the first embodiment by the mechanical arrangement of the third shaft line A 3 , which comprises double clutches, permitting speed change under torque, the “power shift” transmission so called by specialists, with electrical or hydraulic control of known type and not shown in detail. 
     In the first and second embodiments described with reference to FIGS. 3 and 4, it is possible to select four forward speeds and four reverse speeds, to turn the shaft  37  in the corresponding regime and in the corresponding direction and to transmit its movement by cardan shafts  9  and  10  in the middle of the drive axles  1  and  2 . 
     The selection of the speed ratio results from the coaction or reciprocal inactivity of the different mechanical clutch members, as indicated in the speed table, in which the numeral  1  indicates the clutching activity  18   a  or  18   b  or the drive by one of the clutch wheels  40  to  43  with a plate  44  or  45  of the shaft  37  and of the drive axles  1  and  2 , whilst the numeral  0  indicates the dead point of the clutch  18   a  or  18   b , or the absence of clutching of a toothed wheel  40  to  43  in the free wheel condition on shaft  37 . 
     With reference to FIG. 5, identical or functionally equivalent elements to those of FIG. 4 are shown by the same reference numerals. 
     In FIG. 5, a third embodiment of gearbox according to the invention permits changing speeds under torque, the “power shift” transmission so called by specialists, by modifying the mechanical arrangements of the three shaft lines A 1 , A 2 , A 3 . These arrangements comprise for example intermediate support bearings  108  and  109  for the first shaft line A 1  comprising the double conical pinion  15   a  or  15   b , a double hydraulic forward drive clutch with three plates  100 - 101 - 102 , and associated toothed wheels  103  and  104  secured respectively to the plates  101  and  102 , and a hydraulic clutch with two plates  105 - 106  for reverse drive with an associated toothed wheel  107  secured to the plate  106 . The toothed wheels  103 ,  104  and  107  of the first shaft line A 1  engage continuously with the corresponding toothed wheels  24 ,  26  and  29  of the second shaft line A 2 . 
     A wheel  25  or  28  or  29  of the second shaft line A 2  can transmit the movement of the second shaft line A 2  to the third shaft  37 , as a function of the force of the various clutches of the gearbox, and in particular the clutch  27 - 28  of the second shaft line A 2 . 
     The toothed wheels  25 ,  28  and  29  engage with toothed wheels  50 ,  52  and  54  of the third shaft  37 : the first and third toothed wheels  50  and  54  are mounted disengageably and engageably under the action of clutch means  50 - 51  and  53 - 54  respectively. The second toothed wheel  52  is mounted fixedly on the shaft  37 , because the toothed wheel  28  of the second shaft line A 2  is disengageable. 
     These arrangements permit obtaining six forward speeds and three reverse speeds, as will be seen from the speed table indicating the condition of driving ( 1 ) or not ( 0 ) of one of the toothed wheels  103 ,  104  or  107  or of a member  51 ,  52  or  53  of the third shaft  37  as a function of the force of the various forward drive clutches  100 - 101 ,  100 - 102 , or of reverse drive  105 - 106  and selection clutches  50 - 51 ,  27 - 28 ,  53 - 54  of the two shaft lines A 2  and A 3 . 
     With reference to FIG. 6, an arrangement with three parallel shaft lines A 1 , A 2 , A 3  of a gearbox according to the invention provides the advantage of having shaft outputs to drive the front and rear axles substantially in the desired plane (in general the longitudinal median plane of the corresponding machine), and moreover permits substantially reducing the longitudinal size of the mechanical assembly comprising the motor M and the gearbox  12 . 
     Similarly, the passage provided through the hollow shaft of the converter  14  to transmit the movement of drive shaft  17  permits reducing the transverse size of the mounting of the hydraulic pumps P driven by the power takeoff shaft  16 , such that the assembly shown comprising the motor M, the gearbox  12  and these hydraulic pumps P has a limited transverse size. 
     Moreover, the use of angled transmission  15  with a double conical pinion  15   a ,  15   b  supplying alternatively forward movement and reverse movement, permits having a relay shaft to reverse the direction of rotation for reverse drive. 
     The invention described with reference to particular embodiments is in no way thereby limited, but on the contrary covers any modification of form and all variation of embodiment within the scope and spirit of the invention. 
     Thus, the invention also covers any modified embodiment not shown, of a gearbox comprising at least three parallel shaft lines and arranged substantially longitudinally, having a reduced size, and of simple and economic construction. To this end, there can be used an angled transmission with a single conical pinion instead of an angled transmission with a double conical pinion described with reference to FIGS. 1 to  6 , so as to reduce the longitudinal size of the gearbox by a length corresponding to the reverse drive pinion  15   b , to the associated clutch  18   b  and to the toothed reverse drive wheel  19   b . This modification to reduce the size requires providing a fourth shaft, namely a reversing shaft for reverse movement, parallel to the three shaft lines A 1 , A 2 , A 3  described with reference to FIGS. 1 to  6 . 
     This reversing shaft for reverse drive coacts disengageably with the shafts A 1  and A 2 ; when this reversing shaft is disengaged, the gear box according to the invention operates in forward drive; when this reversing shaft is engaged, the movement of shaft A 1  drives the reversing shaft which in turn drives the shaft A 2  and the gearbox operates in reverse drive. 
     The increase of the dimension of the gearbox in the transverse direction by virtue of the addition of this reversing shaft is compensated by the decrease of the longitudinal size of the gearbox, such that the volume of the casing of this modification is comparable to the volume of the casing  13  described with reference to FIGS. 5 and 6.