CA1076963A - Tractor vehicle in particular for agricultural use - Google Patents
Tractor vehicle in particular for agricultural useInfo
- Publication number
- CA1076963A CA1076963A CA270,816A CA270816A CA1076963A CA 1076963 A CA1076963 A CA 1076963A CA 270816 A CA270816 A CA 270816A CA 1076963 A CA1076963 A CA 1076963A
- Authority
- CA
- Canada
- Prior art keywords
- vehicle
- chassis
- cab
- wheels
- driving
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D33/00—Superstructures for load-carrying vehicles
- B62D33/06—Drivers' cabs
- B62D33/063—Drivers' cabs movable from one position into at least one other position, e.g. tiltable, pivotable about a vertical axis, displaceable from one side of the vehicle to the other
- B62D33/0636—Drivers' cabs movable from one position into at least one other position, e.g. tiltable, pivotable about a vertical axis, displaceable from one side of the vehicle to the other displaceable along a linear path
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D11/00—Steering non-deflectable wheels; Steering endless tracks or the like
- B62D11/02—Steering non-deflectable wheels; Steering endless tracks or the like by differentially driving ground-engaging elements on opposite vehicle sides
- B62D11/06—Steering non-deflectable wheels; Steering endless tracks or the like by differentially driving ground-engaging elements on opposite vehicle sides by means of a single main power source
- B62D11/10—Steering non-deflectable wheels; Steering endless tracks or the like by differentially driving ground-engaging elements on opposite vehicle sides by means of a single main power source using gearings with differential power outputs on opposite sides, e.g. twin-differential or epicyclic gears
- B62D11/14—Steering non-deflectable wheels; Steering endless tracks or the like by differentially driving ground-engaging elements on opposite vehicle sides by means of a single main power source using gearings with differential power outputs on opposite sides, e.g. twin-differential or epicyclic gears differential power outputs being effected by additional power supply to one side, e.g. power originating from secondary power source
- B62D11/18—Steering non-deflectable wheels; Steering endless tracks or the like by differentially driving ground-engaging elements on opposite vehicle sides by means of a single main power source using gearings with differential power outputs on opposite sides, e.g. twin-differential or epicyclic gears differential power outputs being effected by additional power supply to one side, e.g. power originating from secondary power source the additional power supply being supplied hydraulically
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D33/00—Superstructures for load-carrying vehicles
- B62D33/06—Drivers' cabs
- B62D33/063—Drivers' cabs movable from one position into at least one other position, e.g. tiltable, pivotable about a vertical axis, displaceable from one side of the vehicle to the other
- B62D33/0633—Drivers' cabs movable from one position into at least one other position, e.g. tiltable, pivotable about a vertical axis, displaceable from one side of the vehicle to the other pivotable about a vertical axis
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D49/00—Tractors
- B62D49/06—Tractors adapted for multi-purpose use
- B62D49/0621—Tractors adapted for multi-purpose use comprising traction increasing arrangements, e.g. all-wheel traction devices, multiple-axle traction arrangements, auxiliary traction increasing devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D49/00—Tractors
- B62D49/06—Tractors adapted for multi-purpose use
- B62D49/0621—Tractors adapted for multi-purpose use comprising traction increasing arrangements, e.g. all-wheel traction devices, multiple-axle traction arrangements, auxiliary traction increasing devices
- B62D49/0635—Tractors adapted for multi-purpose use comprising traction increasing arrangements, e.g. all-wheel traction devices, multiple-axle traction arrangements, auxiliary traction increasing devices using additional ground engaging means, e.g. endless tracks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D49/00—Tractors
- B62D49/06—Tractors adapted for multi-purpose use
- B62D49/0685—Reversible tractors adapted for shuttle work
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D53/00—Tractor-trailer combinations; Road trains
- B62D53/02—Tractor-trailer combinations; Road trains comprising a uniaxle tractor unit and a uniaxle trailer unit
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D61/00—Motor vehicles or trailers, characterised by the arrangement or number of wheels, not otherwise provided for, e.g. four wheels in diamond pattern
- B62D61/10—Motor vehicles or trailers, characterised by the arrangement or number of wheels, not otherwise provided for, e.g. four wheels in diamond pattern with more than four wheels
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Arrangement And Driving Of Transmission Devices (AREA)
- Motor Power Transmission Devices (AREA)
- Vehicle Body Suspensions (AREA)
- Non-Deflectable Wheels, Steering Of Trailers, Or Other Steering (AREA)
- Lifting Devices For Agricultural Implements (AREA)
- Agricultural Machines (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE :
A tractor vehicle, in particular for agricultural use, comprising a chassis having a longitudinal axis, at least a front set of driving wheel and a rear set of driving wheels supporting the chassis, a cab, means mounting the cab on the chassis and allowing the cab to travel from one end of the ve-hicle to an opposite end of the vehicle in a direction parallel to said longitudinal axis, an engine and power take-off means carried by the chassis, the power take-off means being for connection to tool menas, first means for controlling the dri-ving and steering of the vehicle and second means for control-ling the tool means to the take-off means, the first and se-cond means being located inside the cab, two independent drive means, one of the drive means being drivingly connected to a pair of said wheels located on one lateral side of said longi-tudinal axis and the other of the drive means being drivingly connected to a pair of said wheels located on an opposite lateral side of said longitudinal axis, transmission means dri-vingly connecting the engine to the two drive means, variator-inverter means included in the two drive means, whereby the engine is capable of driving selectively either of the drive means, both of the drive means at the same time in a symmetri-cal manner and in an unsymmetrical manner. Means are included in the two drive means for reversing the drive means so that the vehicle can be made to travel in two opposite directions, substantially identical raising devices respectively mounted on the chassis at longitudinally opposed ends of the vehicle, a driving station located in the cab and mounted to pivot through at least 180° about a vertical axis relative to the chassis whereby, irrespective of the direction of travel of the vehicle, the operator of the vehicle can face and be close to the stretch of ground to be treated.
A tractor vehicle, in particular for agricultural use, comprising a chassis having a longitudinal axis, at least a front set of driving wheel and a rear set of driving wheels supporting the chassis, a cab, means mounting the cab on the chassis and allowing the cab to travel from one end of the ve-hicle to an opposite end of the vehicle in a direction parallel to said longitudinal axis, an engine and power take-off means carried by the chassis, the power take-off means being for connection to tool menas, first means for controlling the dri-ving and steering of the vehicle and second means for control-ling the tool means to the take-off means, the first and se-cond means being located inside the cab, two independent drive means, one of the drive means being drivingly connected to a pair of said wheels located on one lateral side of said longi-tudinal axis and the other of the drive means being drivingly connected to a pair of said wheels located on an opposite lateral side of said longitudinal axis, transmission means dri-vingly connecting the engine to the two drive means, variator-inverter means included in the two drive means, whereby the engine is capable of driving selectively either of the drive means, both of the drive means at the same time in a symmetri-cal manner and in an unsymmetrical manner. Means are included in the two drive means for reversing the drive means so that the vehicle can be made to travel in two opposite directions, substantially identical raising devices respectively mounted on the chassis at longitudinally opposed ends of the vehicle, a driving station located in the cab and mounted to pivot through at least 180° about a vertical axis relative to the chassis whereby, irrespective of the direction of travel of the vehicle, the operator of the vehicle can face and be close to the stretch of ground to be treated.
Description
.
The invention relates to~a tractor vehicle in particular for agricultural use, although this machine may be employed for other pur~oses, such as public works.
These vehicles, which are well known in the rural world, usually comprise a chassis supported by two sets of driving and steering wheels, the chassis being surmounted by a driving cab in which the operator is placed. The chassis most often has, at the rear, a power take-off which is capable of being coupled to earth working tools, a "three point" coupling, and a hydraulic raising device. These various devices are sometimes located in the front of the machine when the latter does not have a towing function but a pushing function. This type of machine, which is well known to cultivators, has many drawbacks as concerns its design, its handling and its driving on the ground.
As concerns the developed power:
The conventional tractor has only two driving wheels which are really adapted and capable of developing the power that the engine is capable of furnishing.
Sometimes a front driving axle is added to improve the efficiency of the tractor. Generally, it might be said that tractors of more than lOO HP utilize very inefficiently the power of their engine. For high powers, tractors have a poor adherence to the ground. To overcome this it is necessary to render them considerably heavier (inflation of the wheels with water - provision of many weighting masses, etc.). The dimensions of the pneumatic tires are also increased (45 to 50 cm). The pneumatic equipment of these tractors is no longer sufficiently polyvalent and the more ; 30 they are widened the less they can be employed, principally t~
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. .
for crops arranged in rows (beetroots, potatoes, treatmant of cereals, etc.). They must he replaced by narrow equip-ments, most of the time coupled at the spacing of the crops.
The use of wide pneumatic tires presses down an excessively large area of earth which is sometimes difficult to recover.
The wear of these tires is greater and costs more than that of smaller tires.
The front driving axles are often imperfectly adapted.
For certain work the equilibrium of the weight between the front driving axle and the rear driving axle is unsatis-factory in many cases. The front driving axles reduce the turning circles. The tractor becomes much less easy to handle and does not allow any skid-turning at the field ends.
The differential locking is only valid for straight-i ahead travel. It is not always possible with front driving axles. It is difficult to achieve a transmission which is proportional to the travel with a driving axle which is located under a trailer vehicle (too many universal joints, which are difficult to use when turning, etc.).
; As concerns the items of equipment:
There is no front power take-off which is really adapted for the purpose, whence the necessity to provide lay shafts leading from the rear power take-off with the use of uni-versal joints, speed reducing shafts, etc. Which arrange-ment is hardly elegant from the mechanical point of view.
There is no front lifting. This is mainly due to the fact that the tractors no longer have a chassis on which fixing means for mu~tiple uses may be provided. There is no bearing platform on which there may be adapted different i,, ~ _ ~ _ . . .
-` ~076963 containers (fertilizers, seeds, treating products) or other adaptations (cranes, buckets).
As concerns the driving of the tractor:
The gear-boxes are not all equipped with synchronized speeds. In any case it is very difficult to change speed when towing a heavy load on wet ground.
There is no possibility of reversing the travel.
Tractors are equipped in such manner that they can only be employed in one direction of travel, and it is up to the user to make the best of the situation. To do this, he must most of the time drive his tractor while looking at the tool located behind him.
There is no continuous speed variator from 0 to 27 km per hour. Most of the time no speed really corresponds to the envisaged work or to the equipment towed, coupled and used.
The speed, raising and steering controls are often very badly positioned and do not take into account that these machines are employed essentially for working the earth ~the levers located between often soiled feet reduce the freedom of movement of the driver, etc.).
Poor visibility in front owing to the front driving axle and the engine, and at the rear owing to the fact that the driver must turn round for this purpose. Visibility is bad in many other applications since the cab is inserted between the two rear wheels of the machine.
Comfort is very often poor, since the tractor follows rather badly the contour of the ground. Without a forward driving axle the comfort is still worse.
An object of the invention is to overcome these various _ ~ _ 1C~7f~9~;3 drawbacks, the li~t of which is not exhau~tive, and concerns a mobile machine of the tractor type equipped with wheel~
pro~ided with pneumatic tire~ of small width which may con-sequentl~ be employed in any type oi culti~ation, this feature resulting irom the iact that the chassi~ is supported by six driving and steering wheels on which there are distributed the load and the forces required for moving the machine, these wheels being driven in such manner that it is possible, in the extreme case, to lock the three wheels located on one ~ide of the cha~sis and drive the other three to achieve a complete ~ -~kid-turning of the vehicle.
~ astly, the vehicle is provided both in iront and at the rear with coupling and raising means and force take-offs allowing its utilization in either direction, since it is ca-pable of moving in two opposite directions owing to the rever-~ibility of the wheel driving means. ~he driving, the ¢ontrol and the actuation Or the tools connected to the vehicle are, moreo~er, rendered possible by the fact that the cab or com-partment is mo~able in translation and that the driving station is pivotably mounted 90 that the operator is always iacing the stretch of ground to be treated, irrespective of the direction of the vehicle.
According to the present invention there is provided a tractor vehicle, in particular ior agricultural use, com-prising a chassis having a longitudinal axis, at lea~t a iront set of dri~ing wheel and a rear set oi driving wheels supporting the cha~sis, a cab, means mounting the cab on the chassis and allowing the cab to travel from one end of the vehicle to an oppo~ite end of the vehicle in a direction parallel to said longitudinal axis, an engine and power take-off means carried by the chassis, the power take-off means being for connection to tool mean~, first means for controlling the driving and steering o~ the vehicle and second means for controlling the .... .
- 107~;9~i3 tool means to the take-o~f mean~, the first and ~econd mean-~being located in~ide the cab, two independent drive means, one of the drive mean~ being drivingly connected to a pair of said wheels located on one lateral side of said longitudi-nal axis and the other of the drive means being drivingly con-nected to a pair of said wheels located on an oppo~ite lateral side of said longitudinal axi~, tran~mission mean~ drivingly connecting the engine to the two drive means, variator-inrerter means included in the two dri~e mean~, whereby the engine is 1 capable of driving selectively either of the drive mean~, both of the drive means at the same time in a symmetrical manner and in an unsymmetrical manner, means included in the two drive means for rever~ing the drive means ~o that the vehlcle can be made to travel in two opposite directions, ~ubstantially identical rai~ing devices respectively mounted on the chaseis at longitudinally oppo~ed ends of the vehicle, a driving sta-tion located in the cab and mounted to pivot through at least 180 about a vertical axis relative to the chassis whereby, irrespective of the direction of travel of the vehicle, the operator of the vehicle can face and be close to the stretch of ground to be treated.
According to a pre~erred embodiment, each of the two independent drives comprise~ a variable delivery hydraulic pump operating in a clo~ed circuit, the two pump~ being connected to two outputs of a coupling unit which has a third output intended for a power take-off, and an input for coupl~ng to the crank~haft of the engine.
~ urther features and advantages will be apparent from the en~uing description and the accompanying drawing~ which refer to embodiments to which the invention is not intended to be limited.
In the drawings:
~37~9~3 Fig. 1 is a side elevational view of the tractor vehicle;
Fig. 2 is a top plan view of the vehicle ~hown in Fig. 1, the cab and the front and rear raising device~ having been removed;
Fig. 3 is a diagr~mmatic and partial elevational view of an agricultural tractor according to a 3econd embodi-ment of the invention;
Fig. 4 is a diagrammatic and partial top plan view of the vehicle shown in Fig. 3;
Fig, 5 is a sectional view, to an enlarged scale, of a hydraulic power take-off provided on this vehicle;
- Fig. 6 is a diagram of the hydraulic circuit driving the power take-offs, and .
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107fà~
Fig. 7 is a diagram of the electro-hydraulic control circuit for the raising devices of the vehicle.
The invention concerns a vehicle, such as an agri-cultural machine, comprising in the known manner, a chassis 1 supported by at least two sets of wheels, the chassis being provided with a driving cab 2 and at least one raising device 3 to which the ground-working tools are coupled. This tool may concern a harrow, a plough or any other like tool.
According to the invention, the vehicle comprises three sets of wheels 4a, 4b, 4c so that the load of the vehicle is distributed among six wheels, whereby it is possible to employ narrow rims for receiving pneumatic tires whose tread is such that the vehicle can pass freely between rows of plants which have even been spaced relatively I close together. These narrow pneumatic tires are, moreover, much cheaper than those employed on conventional tractors.
Furthermore, they require no interchanging when passing from one crop to another, so that the operator has no need to have a stock of tires of different widths and tread patterns.
The fact of employing six wheels not only enables the weight of the vehicle to be evenly distributed, it enables the energy which must be developed for driving the vehicle to be distributed in a symmetrical manner.
For this purpose, as can be seen in Fig. 2, the wheels 4a, 4b, 4c located on one side of the chassis are supplied with power by a drive independent of the drive driving the other wheels 4a, 4b, 4c on the other side of the chassis.
~769G~
The power is uniformly distributed among the six wheels of equal size and is transmitted to these wheels by two pumps 5 and 6 which have a variable delivery or flow and are reversible. These pumps are of the barrel type and include in the conventional manner a booster pump and a protecting and exchanging unit. They are employed as a hydraulic inverter-variator and operate in a closed circuit with their respective wheels.
Thus each pump drives a set of three wheels located on each longitudinal side of the chassis, and each wheel is provided with a double-displacement hydraulic motor 7.
The pumps 5 and 6 are connected to a coupling box 8 through the centre of which box a power take-off shaft 9 extends, this shaft projecting at one end at the rear output of the engine, the other end being connected to the front power take-off unit 10 through an elastically yieldable lug-type coupling 11. The power take-off proper 12 is rendered operative by a clutch 13 contained in the power take-off box, and this clutch cooperates with a speed reducer 14 and an electro-hydra~lic distributor valve 15. This mech-anical construction is of cour,se also provided at the other end of the vehicle.
The power is furnished to the two pumps 5 and 6 by a Diesel engine 16 which also supplies the energy for the two power take-offs 12, which latter may be rendered operative alternately or simultaneously.
The pumps are controlled electrically from the driving station and are fully independent of each other. By varying the delivery or flow of one pump with respect to the other, the vehicle can be skid-turned. This utilization .. - ~ -~L~J7f~963 enables the turning circle of the machine to be reduced when the nature of the ground allows this. In the extreme case, it is possible to completely neutralize one pump so that the three wheels located on one side of the vehicle are locked, and then proportionally supply fluid to the other pump so as to achieve a complete skid-turn, on the spot, of the machine on the locked set of wheels.
The vehicle is made to travel by inclining the swash-plates of the two pumps 5 and 6 at the same angle so as to obtain identical deliveries from the pumps. The travelling speed of the vehicle is therefore proportional to the delivery of the pumps, and the variation of the delivery of one pump with respect to the other enables the machine to be turned to the right or the left. On the other hand, an identical variation of the deliveries of the two pumps enables the machine to be moved forwardly or rearwardly, or stopped. This arrangement provides a differential locking with no mechanical connection at the different travelling speeds of each set of wheels. Furthermore, when stationary, a hydrostatic braking of each wheel is achieved.
The vehicle drive controls are foot-operated from the driving cab. Under the right foot, there is a forward drive control of the vehicle whereas under the left foot 2S there is a reverse drive control. These pedals actuate the control device of the delivery of the two pumps 5 and 6, and these controls are identical for the two pumps.
The vehicle is steered by means of a steering-wheel which actuates the control of the deliveries of the two pumps;
in thi~ case, the two pumps are controlled differently.
_ ~ _ ~07~i9~3 Thus, when the vehicle is stationary, if the steering wheel is turned to the right through an angle ~ , the control device will maintain the delivery of the right pump null and produce a delivery of +dl of the left pump.
This will skid-turn the machine on itself (the set of right wheels being locked). If in addition it is desired that the machine travel forward, the right pedal will be depressed and the control device will then produce a delivery of +d2 of the two pumps.
This therefore gives, for the right pump: Dr = + d2 and for the left pump: Dl = dl + d2, the machine will therefore travel forward in turning to the right since the value Dl ~> Dr.
The steering wheels may be actuated in the following lS manner: thus it is possible to:
- actuate the front driving wheels, - actuate the rear driving wheels, - actuate the front and rear driving wheels simultaneously.
This choice is made by means of separate control circui~s for the front steering and rear steering.
The steering wheel actuates the control device of the delivery of the hydraulic pumps, but also the two orbitrols (step-by-step rotary distributor valves) for steering, one of which is mounted on the front set of wheels and the other on the rear axle. These orbitrols are actuated by electric motor-speed reducer units controlled by steering control circuits fixed to the steering wheel.
If the steering wheel is turned in a given direction, there will be achieved both a control of the deliveries of the pumps 5 and 6 and a control of the electric motor-speed reducer units (not shown) actuating the orbitrols so as to /d -- ~2 --~ . .. ....
. ' ~7~i9~i3 achieve a change in direction.
As the vehicle is capable of travelling in two opposite directions, it is obviously desirable that it be capable of operating indifferently for towing or pushing, irrespective of its direction of travel. For this purpose, the vehicle is provided with a raising device 3 in the front and at the rear, these two devices being identical.
The raising device comprises two lower arms 17 which are connected to two upper arms or links 18, pivoted at 19 to the chassis 1 of the vehicle, through the ~gency of two stays 20, so that this assembly forms, with the cross-members of the chassis, a deformable parallelogram structure which is subjected to the action of two jacks 21 whose pistons 22 are connected by lugs 23 to the upper raising arms or links 18.
The two lower raising arms 17 are connected, in the region of their pivotal mounting 24, to a flexion bar which is combined with a force sensor 25 whereas the upper arms 18 are combined with a position sensor 26 controlling the height of the raising device.
These two raising devices have an independent control and the required hydraulic power is provided by a pump 27 driven by the Diesel engine 16.
This pump supplies fluid either to the two outer jacks 21 of the front raising device or to those of the rear raising device by way of hydraulic electro-distributing valves.
The control of the position determined by the sensor 26 associated with the raising arms is ensured electrically from the driving station through an electric positioning r;$~ .
~076~f~3 control unit. This control unit is actuated, on one hand, by the position sensor 26 mounted between the raising arms or links, and, on the other hand, by signals coming from the value that the operator feeds into or sets on the posi-tion control sector in the cab. In this way, the operator feeds the required value into the position control sector and the electro-distributor valve (not shown) supplies fluid to the raising jacks 21. When the latter reach the chosen position, the value of the signal produced by the position sensor 26 becomes such that the control unit produces the closure of the electro-distributor valve.
The force control device is also actuated electrically from the driving station through an electric control unit.
This control unit is actuated, on one hand, by the signal of the force sensor 25 located on the flexion bar 24 interconnecting the two lower arms 17 and, on the other hand, by the signals coming from the value that the operator feeds into or sets on the force control sector in the cab.
Operation of the force control device.
A value E is fed into the force control sector in the cab. There corresponds to this value E a signal e which is fed to the control unit.
If the buckling in the flexion bar becomes great, so that the force sensor 25 connected thereto indicates a value el ~ e, this force control unit then produces the opening of the electro-distributor valve and thus raises the lower arms 17 so that the towing force is relieved.
When the value of el ~ e, this unit then produces the closure of the electro-distributor valve.
,_ ~ _ , .. .
~07tj9t;3 As the chosen pcsition has been exceeded, the position control device takes over the regulation of the raising and returns the arms to the initial positions.
As the vehicle is capable of travelling in two oppo-S site directions (reversibility of the pumps 5 and 6), a feature of the vehicle is to have a cab 2 which is movable in translation along upper longitudinal members 11 of the chassis 1. The base of this cab i5 mounted on a carriage 29 provided with rollers 30 which roll along section members 11 constituting the upper longitudinal members of the chassis.
This cab, movable in translation in opposite direc-tions, may be held stationary in any position by locking means, such as pins, studs, spring~biased locks, screws or other means.
Preferably, this cab is held stationary in the region of the two end faces of the vehicle so as to leave free a surface S which constitutes a platform for receiving various appliances such as sprayers, distributors, tanks, buckets, etc.
Further, in order to allow the operator to face always in the direction of the stretch of ground to be treated, the driving station 31 in this cab is mounted to be rotatable on a pivotal hub so that the whole of the station, including the control means, can pivot through at least 180.
~he connections between the various drivins means of the machine (Diesel engine, power take-off, pump coupling box) are achieved by elastic couplings allowing a disassembly of a single element of the transmission system in any region.
The machine according to the invention is so designed PO71~9~;3 as to be utilizable on any ground, including the road, since the front set of wheels can be declutched, and its utilization is greatly facilitated by the two independent drives for the sets of wheels located on each side of the chassis, since it is possible, by varying the deliveries of the pumps, to cause the vehicle to travel in one direction or the other or to obtain the locking of one series of wheels to obtain its skid-turning on the spot.
As concerns the steering, the wheels of the front and rear sets of wheels 4a, 4c are driving and steering wheels and the wheels 4b of the intermediate set of wheels are merely driving wheels.
The machine according to the invention has the following advantages:
- the machine can travel in both directions at any speed between O and 27 km per hour owing to the hydrostatic transmission;
- the items of equipment are identical in the front and at the rear so that it is possible to couple the tools - both to the front and to the rear of the machine;
- the stPering is effected on two axles, namely the front axle and rear axle, the centre axle remaining fixed, with the result that there is an improved turning circle.
The latter can be still further improved by skid-turning the machine by means of the hydraulic pumps;
- there is a differential locking on all the wheeLs in all conditions of use in a straight-ahead travel and when turning;
- the cab, located completely above the wheels, im-proves the front visibility. The cab may be advanced or shifted back, depending on the work to be carried out, .~
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~76963 and the driver can choose the most suitable position;
- the driving station inside the cab can turn through 0 - 180 and assume any intermediate position;
- the machine is much more easy to handle than con-ventional tractors, since the transmissions are hydraulicand not mechanical.
The vehicle shown in Figs. 3 and 4 comprises a chassis 1 supported by two sets of driving wheels 102 and 103 and on which there is ~ixed a driving cab 104 enclosing the vehicle driving means and the means controlling the tools which may be coupled to two power take-offs 105 and 106 disposed respectively in the front and at the rear of the chassis.
The chassis lOl comprises, in the longitudinal direc-tion, two sections lOla and lOlb which are interconnected to pivot with respect to each other about a vertical axis X-X which is offset toward the front of the vehicle ~ith respect to the middle of the latter, that is to say, with respect to the transverse plane midway between the front and rear faces of the chassis.
The f-ont section lOla of the -hassis has a generally parallel-sided shape and is extended rearwardly by a portion 107a having a trapezoidal horizontal section, whereas the rear section lOlb also has a generally parallel-sided shape and is extended forwardly by an upper portion and a 25 lower portion 107b having a trapezoidal horizontal section.
These portion~ 107b terminate in forks 108 between which there are engaged brackets 109 which are integral with the portion 107a. These forks and brackets are pivotally interconnected by shaft portions 110. Two jacks 111 are 30 mounted on the front face of the parallel-sided portion . ~ . . .
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~07~963 of the section lOlb between the levels of the portions 107b so as to be disposed in the same horizontal plane and pivotable about vertical axes Y-Y located on said face.
The ends of their rods 112 are mounted in two forks 113, respectively fixed to each of the two sides of the chassis portion 107a, to pivot about vertical axes Z-Z. It is essential to note that the general pivot axis X-X of the chassis is disposed in a transverse plane of the vehicle located practically at the rear of the front set of wheels 102. The chassis 101 is completed by an upper platform 114 which covers the entire area of the rear section lOlb and extends forwardly beyond this part in overhanging relation to above the middle of the front set of wheels 102, this overhanging part carrying the cab 104 in the position for normal travel o~ the vehicle.
Such a pivoted arrangement of the chassis permits reducing to the maximum extent the gap between the latter and the wheels, so that it is possible to locate therein devices which are larger than in a rigid chassis. Indeed, a rigid cilassis must provide a sufficient clearance between , the wheels and the chassis to permit a suitable steering angle of the steering wheels. The gain as concerns the turning circle is between 20 and 30%. The offsetting of the pivotal connection in the direction of the-front set of wheels above all permits a solution of the problem of the steerability of the machine in rows of plants. Indeed, the inclination of the front section of the chassis through a small angle, for example 10 on each side of the median axis, has practically no effect on the performance of the tools which may be coupled to the rear of the vehicle.
-- ~ _ ~0~7ti9~3 The pivotal connection of the chassis is distinctly simpler, from the structural point of view, than the complex pivotal connection of steering wheels. It very definitely simplifies the supply of fluid to the driving wheels, each of which, as mentioned hereinafter, are driven by a hydraulic motor 115, since these wheels become fixed in position on the chassis.
This results in a considerable reduction in the cost of the vehicle and a most appreciable mechanical simplification.
In addition to the hydraulic motors 115 which are iO integral with the front wheels 102 and drive the latter, and the front power take-off 105, the front section 101a of the chassis carries two batteries 116 and a cooling device 117.
Likewise, apart from the hydraulic motors 115 integral with and driving the rear wheels 103 and the rear power take-off 106, the rear section lOlb of the chassis carries a drive unit constituted by an internal combustion engine 118 whose crankshaft is coupled to the input of a coupling box 119 which has three outputs respectively connected to ~0 a variable delive~y and xeversible hydraulic pump 120 ~or dri~ing the power take-offs and to two units having a single driving shaft each unit being constituted by a variable delivery and reversible hydraulic pump 121a or 121b for driving the hydraulic motors 115, a booster pu~p 122, a hydraulic pump 123a or 123b for driving the raising devices described hereinafter and, on one side, a pump 124a driving the hydraulic motor of the fan of the cooling device and, on the other side, a pump 124b actuating the jacks 111.
As shown in more detail in Fig~ 5, each of the hydraulic power take-offs 105 or 106 comprises a case 125 within which ., ) .~
_ ~g _ . _ .. . . . .
~-7~9~
there is disposed a speed-reducing train of gears 126 the input of which is integral with the shaft of a hydraulic motor 127, whereas the output is constituted by a hollow sleeve 128 which receives, in two coaxial stepped bores of different diameters, the central splined part of a power take-off shaft 129, the latter being fitted in corresponding splines of the associated bore, and one of the splined ends 129a of this shaft, the other splined end 129b of the latter projecting from the sleeve 128 for connection to a tool to be driven. One of the ends 129a and 129b of the shaft has a small number of splines, for example six, whereas the other has a larger number of splines, for example twenty-one, so that, depending on which end is disposed inside the sleeve, the tool can be driven at two different speeds.
Thus, for example, if the speed of rotation of the motor t 127 is 3000 rpm, the utilizable end of the power take-off shaft can drive the tool at 540 rpm or 1000 rpm.
As shown in Fig. 6, the two outputs of the reversible pump 120 are connected by pipes 130a and 130b respectively to two inputs of the motors 127 for driving the power take-offs, whereas the other two inputs of these motors are interconnected by a third pipe 130c, the assembly thereby constituting a closed pipe circuit. Two electro-hydraulically actuated hydraulic distributor valves 131a and 131b are interposed, one, between the pipes 130a and 130c and, the other, between the pipes 130b and 130c so as to permit supplying fluid to one or the other of the motors 127 or to both at the same time.
The circuit further comprises two pipes 132a and 132b branch connected to the pipes 130b and 130c between the distributor valve 131b and the motor 127 and connected to ~0769t;3 the inputs of an auxiliary hydraulic motor 133 which is adapted to drive one of the tools 133a with which the vehicle is provided, these pipes 132a and 132b having check valves 134 which allow the passage of the fluid only in the direc-tion of the motor. Stop valves 135 are inserted in thepipes 130b and 130c between the motor 127 and the branch connections of the pipes 132a and 132b.
The pump 120 is supplied with oil, as are moreover the pumps 121a and 121b, from an oil tank 13~ which is fixed outside on one of the sides of the section 101b of the chassis in front of the rear wheel 103. A fuel tank 137 for supplying fuel to the engine 118 is disposed symmetric-ally on the other side of this section.
This circuit drives the front and rear power take-offs 105 and 106 either individually or simultaneously in one direction or the other and at a variable speed which may reach either of the aforementioned two values, the two power take-offs necessarily rotating at the same speed when they are employed simultaneously owing to the use of a - 20 hydraulic control circuit in series.
Such a power take-off driving circuit has the great interest of taking advantage of the presence of a central hydraulic drive for the vehicle constituted by the engine 118, the box 119, the pumps 121a and 121b and-the motors 115 so as to provide a hydraulic power transmission with no difficulty. Such an arrangement uses the same oil tank, the same cooling device and the same filtering means as those already existing in the vehicle drive device.
In addition to the simplicity of construction of this power take-off drive circuit, there is an excellent utili-zation of these power take-offs owing to the extreme : ~
107~9~;3 flexibility of use of its component parts and in particular the variable delivery pump.
The vehicle further comprises at each of its two longi-tudinal ends a hydraulic raising device 138 or 139, two of these devices being provided at each end, one on the left side and the other on the right side. As shown in Figs. 3 and 4, each of these four devices is disposed in a vertical plane parallel to the longitudinal median plane of the vehicle and is constituted by a lower arm 140, an upper arm 141, a stay 142, and a jack 143. The two arms 140 and 141 are mounted at one of their ends on the front face of the section lOla of the chassis to pivot about horizontal transverse axes and respectively in the lower region and upper region of this front face.
The stay 142 is pivoted, on one hand, to the other end of the arm 140 and, on the other hand, to the lower arm 141 in the vicinity of the other end of the lower arm 141, this end being adapted for the fixing of a tool.
The jack 143 is pivoted in the lower region of the
The invention relates to~a tractor vehicle in particular for agricultural use, although this machine may be employed for other pur~oses, such as public works.
These vehicles, which are well known in the rural world, usually comprise a chassis supported by two sets of driving and steering wheels, the chassis being surmounted by a driving cab in which the operator is placed. The chassis most often has, at the rear, a power take-off which is capable of being coupled to earth working tools, a "three point" coupling, and a hydraulic raising device. These various devices are sometimes located in the front of the machine when the latter does not have a towing function but a pushing function. This type of machine, which is well known to cultivators, has many drawbacks as concerns its design, its handling and its driving on the ground.
As concerns the developed power:
The conventional tractor has only two driving wheels which are really adapted and capable of developing the power that the engine is capable of furnishing.
Sometimes a front driving axle is added to improve the efficiency of the tractor. Generally, it might be said that tractors of more than lOO HP utilize very inefficiently the power of their engine. For high powers, tractors have a poor adherence to the ground. To overcome this it is necessary to render them considerably heavier (inflation of the wheels with water - provision of many weighting masses, etc.). The dimensions of the pneumatic tires are also increased (45 to 50 cm). The pneumatic equipment of these tractors is no longer sufficiently polyvalent and the more ; 30 they are widened the less they can be employed, principally t~
;' .
. .
for crops arranged in rows (beetroots, potatoes, treatmant of cereals, etc.). They must he replaced by narrow equip-ments, most of the time coupled at the spacing of the crops.
The use of wide pneumatic tires presses down an excessively large area of earth which is sometimes difficult to recover.
The wear of these tires is greater and costs more than that of smaller tires.
The front driving axles are often imperfectly adapted.
For certain work the equilibrium of the weight between the front driving axle and the rear driving axle is unsatis-factory in many cases. The front driving axles reduce the turning circles. The tractor becomes much less easy to handle and does not allow any skid-turning at the field ends.
The differential locking is only valid for straight-i ahead travel. It is not always possible with front driving axles. It is difficult to achieve a transmission which is proportional to the travel with a driving axle which is located under a trailer vehicle (too many universal joints, which are difficult to use when turning, etc.).
; As concerns the items of equipment:
There is no front power take-off which is really adapted for the purpose, whence the necessity to provide lay shafts leading from the rear power take-off with the use of uni-versal joints, speed reducing shafts, etc. Which arrange-ment is hardly elegant from the mechanical point of view.
There is no front lifting. This is mainly due to the fact that the tractors no longer have a chassis on which fixing means for mu~tiple uses may be provided. There is no bearing platform on which there may be adapted different i,, ~ _ ~ _ . . .
-` ~076963 containers (fertilizers, seeds, treating products) or other adaptations (cranes, buckets).
As concerns the driving of the tractor:
The gear-boxes are not all equipped with synchronized speeds. In any case it is very difficult to change speed when towing a heavy load on wet ground.
There is no possibility of reversing the travel.
Tractors are equipped in such manner that they can only be employed in one direction of travel, and it is up to the user to make the best of the situation. To do this, he must most of the time drive his tractor while looking at the tool located behind him.
There is no continuous speed variator from 0 to 27 km per hour. Most of the time no speed really corresponds to the envisaged work or to the equipment towed, coupled and used.
The speed, raising and steering controls are often very badly positioned and do not take into account that these machines are employed essentially for working the earth ~the levers located between often soiled feet reduce the freedom of movement of the driver, etc.).
Poor visibility in front owing to the front driving axle and the engine, and at the rear owing to the fact that the driver must turn round for this purpose. Visibility is bad in many other applications since the cab is inserted between the two rear wheels of the machine.
Comfort is very often poor, since the tractor follows rather badly the contour of the ground. Without a forward driving axle the comfort is still worse.
An object of the invention is to overcome these various _ ~ _ 1C~7f~9~;3 drawbacks, the li~t of which is not exhau~tive, and concerns a mobile machine of the tractor type equipped with wheel~
pro~ided with pneumatic tire~ of small width which may con-sequentl~ be employed in any type oi culti~ation, this feature resulting irom the iact that the chassi~ is supported by six driving and steering wheels on which there are distributed the load and the forces required for moving the machine, these wheels being driven in such manner that it is possible, in the extreme case, to lock the three wheels located on one ~ide of the cha~sis and drive the other three to achieve a complete ~ -~kid-turning of the vehicle.
~ astly, the vehicle is provided both in iront and at the rear with coupling and raising means and force take-offs allowing its utilization in either direction, since it is ca-pable of moving in two opposite directions owing to the rever-~ibility of the wheel driving means. ~he driving, the ¢ontrol and the actuation Or the tools connected to the vehicle are, moreo~er, rendered possible by the fact that the cab or com-partment is mo~able in translation and that the driving station is pivotably mounted 90 that the operator is always iacing the stretch of ground to be treated, irrespective of the direction of the vehicle.
According to the present invention there is provided a tractor vehicle, in particular ior agricultural use, com-prising a chassis having a longitudinal axis, at lea~t a iront set of dri~ing wheel and a rear set oi driving wheels supporting the cha~sis, a cab, means mounting the cab on the chassis and allowing the cab to travel from one end of the vehicle to an oppo~ite end of the vehicle in a direction parallel to said longitudinal axis, an engine and power take-off means carried by the chassis, the power take-off means being for connection to tool mean~, first means for controlling the driving and steering o~ the vehicle and second means for controlling the .... .
- 107~;9~i3 tool means to the take-o~f mean~, the first and ~econd mean-~being located in~ide the cab, two independent drive means, one of the drive mean~ being drivingly connected to a pair of said wheels located on one lateral side of said longitudi-nal axis and the other of the drive means being drivingly con-nected to a pair of said wheels located on an oppo~ite lateral side of said longitudinal axi~, tran~mission mean~ drivingly connecting the engine to the two drive means, variator-inrerter means included in the two dri~e mean~, whereby the engine is 1 capable of driving selectively either of the drive mean~, both of the drive means at the same time in a symmetrical manner and in an unsymmetrical manner, means included in the two drive means for rever~ing the drive means ~o that the vehlcle can be made to travel in two opposite directions, ~ubstantially identical rai~ing devices respectively mounted on the chaseis at longitudinally oppo~ed ends of the vehicle, a driving sta-tion located in the cab and mounted to pivot through at least 180 about a vertical axis relative to the chassis whereby, irrespective of the direction of travel of the vehicle, the operator of the vehicle can face and be close to the stretch of ground to be treated.
According to a pre~erred embodiment, each of the two independent drives comprise~ a variable delivery hydraulic pump operating in a clo~ed circuit, the two pump~ being connected to two outputs of a coupling unit which has a third output intended for a power take-off, and an input for coupl~ng to the crank~haft of the engine.
~ urther features and advantages will be apparent from the en~uing description and the accompanying drawing~ which refer to embodiments to which the invention is not intended to be limited.
In the drawings:
~37~9~3 Fig. 1 is a side elevational view of the tractor vehicle;
Fig. 2 is a top plan view of the vehicle ~hown in Fig. 1, the cab and the front and rear raising device~ having been removed;
Fig. 3 is a diagr~mmatic and partial elevational view of an agricultural tractor according to a 3econd embodi-ment of the invention;
Fig. 4 is a diagrammatic and partial top plan view of the vehicle shown in Fig. 3;
Fig, 5 is a sectional view, to an enlarged scale, of a hydraulic power take-off provided on this vehicle;
- Fig. 6 is a diagram of the hydraulic circuit driving the power take-offs, and .
. .. , ~ . .
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107fà~
Fig. 7 is a diagram of the electro-hydraulic control circuit for the raising devices of the vehicle.
The invention concerns a vehicle, such as an agri-cultural machine, comprising in the known manner, a chassis 1 supported by at least two sets of wheels, the chassis being provided with a driving cab 2 and at least one raising device 3 to which the ground-working tools are coupled. This tool may concern a harrow, a plough or any other like tool.
According to the invention, the vehicle comprises three sets of wheels 4a, 4b, 4c so that the load of the vehicle is distributed among six wheels, whereby it is possible to employ narrow rims for receiving pneumatic tires whose tread is such that the vehicle can pass freely between rows of plants which have even been spaced relatively I close together. These narrow pneumatic tires are, moreover, much cheaper than those employed on conventional tractors.
Furthermore, they require no interchanging when passing from one crop to another, so that the operator has no need to have a stock of tires of different widths and tread patterns.
The fact of employing six wheels not only enables the weight of the vehicle to be evenly distributed, it enables the energy which must be developed for driving the vehicle to be distributed in a symmetrical manner.
For this purpose, as can be seen in Fig. 2, the wheels 4a, 4b, 4c located on one side of the chassis are supplied with power by a drive independent of the drive driving the other wheels 4a, 4b, 4c on the other side of the chassis.
~769G~
The power is uniformly distributed among the six wheels of equal size and is transmitted to these wheels by two pumps 5 and 6 which have a variable delivery or flow and are reversible. These pumps are of the barrel type and include in the conventional manner a booster pump and a protecting and exchanging unit. They are employed as a hydraulic inverter-variator and operate in a closed circuit with their respective wheels.
Thus each pump drives a set of three wheels located on each longitudinal side of the chassis, and each wheel is provided with a double-displacement hydraulic motor 7.
The pumps 5 and 6 are connected to a coupling box 8 through the centre of which box a power take-off shaft 9 extends, this shaft projecting at one end at the rear output of the engine, the other end being connected to the front power take-off unit 10 through an elastically yieldable lug-type coupling 11. The power take-off proper 12 is rendered operative by a clutch 13 contained in the power take-off box, and this clutch cooperates with a speed reducer 14 and an electro-hydra~lic distributor valve 15. This mech-anical construction is of cour,se also provided at the other end of the vehicle.
The power is furnished to the two pumps 5 and 6 by a Diesel engine 16 which also supplies the energy for the two power take-offs 12, which latter may be rendered operative alternately or simultaneously.
The pumps are controlled electrically from the driving station and are fully independent of each other. By varying the delivery or flow of one pump with respect to the other, the vehicle can be skid-turned. This utilization .. - ~ -~L~J7f~963 enables the turning circle of the machine to be reduced when the nature of the ground allows this. In the extreme case, it is possible to completely neutralize one pump so that the three wheels located on one side of the vehicle are locked, and then proportionally supply fluid to the other pump so as to achieve a complete skid-turn, on the spot, of the machine on the locked set of wheels.
The vehicle is made to travel by inclining the swash-plates of the two pumps 5 and 6 at the same angle so as to obtain identical deliveries from the pumps. The travelling speed of the vehicle is therefore proportional to the delivery of the pumps, and the variation of the delivery of one pump with respect to the other enables the machine to be turned to the right or the left. On the other hand, an identical variation of the deliveries of the two pumps enables the machine to be moved forwardly or rearwardly, or stopped. This arrangement provides a differential locking with no mechanical connection at the different travelling speeds of each set of wheels. Furthermore, when stationary, a hydrostatic braking of each wheel is achieved.
The vehicle drive controls are foot-operated from the driving cab. Under the right foot, there is a forward drive control of the vehicle whereas under the left foot 2S there is a reverse drive control. These pedals actuate the control device of the delivery of the two pumps 5 and 6, and these controls are identical for the two pumps.
The vehicle is steered by means of a steering-wheel which actuates the control of the deliveries of the two pumps;
in thi~ case, the two pumps are controlled differently.
_ ~ _ ~07~i9~3 Thus, when the vehicle is stationary, if the steering wheel is turned to the right through an angle ~ , the control device will maintain the delivery of the right pump null and produce a delivery of +dl of the left pump.
This will skid-turn the machine on itself (the set of right wheels being locked). If in addition it is desired that the machine travel forward, the right pedal will be depressed and the control device will then produce a delivery of +d2 of the two pumps.
This therefore gives, for the right pump: Dr = + d2 and for the left pump: Dl = dl + d2, the machine will therefore travel forward in turning to the right since the value Dl ~> Dr.
The steering wheels may be actuated in the following lS manner: thus it is possible to:
- actuate the front driving wheels, - actuate the rear driving wheels, - actuate the front and rear driving wheels simultaneously.
This choice is made by means of separate control circui~s for the front steering and rear steering.
The steering wheel actuates the control device of the delivery of the hydraulic pumps, but also the two orbitrols (step-by-step rotary distributor valves) for steering, one of which is mounted on the front set of wheels and the other on the rear axle. These orbitrols are actuated by electric motor-speed reducer units controlled by steering control circuits fixed to the steering wheel.
If the steering wheel is turned in a given direction, there will be achieved both a control of the deliveries of the pumps 5 and 6 and a control of the electric motor-speed reducer units (not shown) actuating the orbitrols so as to /d -- ~2 --~ . .. ....
. ' ~7~i9~i3 achieve a change in direction.
As the vehicle is capable of travelling in two opposite directions, it is obviously desirable that it be capable of operating indifferently for towing or pushing, irrespective of its direction of travel. For this purpose, the vehicle is provided with a raising device 3 in the front and at the rear, these two devices being identical.
The raising device comprises two lower arms 17 which are connected to two upper arms or links 18, pivoted at 19 to the chassis 1 of the vehicle, through the ~gency of two stays 20, so that this assembly forms, with the cross-members of the chassis, a deformable parallelogram structure which is subjected to the action of two jacks 21 whose pistons 22 are connected by lugs 23 to the upper raising arms or links 18.
The two lower raising arms 17 are connected, in the region of their pivotal mounting 24, to a flexion bar which is combined with a force sensor 25 whereas the upper arms 18 are combined with a position sensor 26 controlling the height of the raising device.
These two raising devices have an independent control and the required hydraulic power is provided by a pump 27 driven by the Diesel engine 16.
This pump supplies fluid either to the two outer jacks 21 of the front raising device or to those of the rear raising device by way of hydraulic electro-distributing valves.
The control of the position determined by the sensor 26 associated with the raising arms is ensured electrically from the driving station through an electric positioning r;$~ .
~076~f~3 control unit. This control unit is actuated, on one hand, by the position sensor 26 mounted between the raising arms or links, and, on the other hand, by signals coming from the value that the operator feeds into or sets on the posi-tion control sector in the cab. In this way, the operator feeds the required value into the position control sector and the electro-distributor valve (not shown) supplies fluid to the raising jacks 21. When the latter reach the chosen position, the value of the signal produced by the position sensor 26 becomes such that the control unit produces the closure of the electro-distributor valve.
The force control device is also actuated electrically from the driving station through an electric control unit.
This control unit is actuated, on one hand, by the signal of the force sensor 25 located on the flexion bar 24 interconnecting the two lower arms 17 and, on the other hand, by the signals coming from the value that the operator feeds into or sets on the force control sector in the cab.
Operation of the force control device.
A value E is fed into the force control sector in the cab. There corresponds to this value E a signal e which is fed to the control unit.
If the buckling in the flexion bar becomes great, so that the force sensor 25 connected thereto indicates a value el ~ e, this force control unit then produces the opening of the electro-distributor valve and thus raises the lower arms 17 so that the towing force is relieved.
When the value of el ~ e, this unit then produces the closure of the electro-distributor valve.
,_ ~ _ , .. .
~07tj9t;3 As the chosen pcsition has been exceeded, the position control device takes over the regulation of the raising and returns the arms to the initial positions.
As the vehicle is capable of travelling in two oppo-S site directions (reversibility of the pumps 5 and 6), a feature of the vehicle is to have a cab 2 which is movable in translation along upper longitudinal members 11 of the chassis 1. The base of this cab i5 mounted on a carriage 29 provided with rollers 30 which roll along section members 11 constituting the upper longitudinal members of the chassis.
This cab, movable in translation in opposite direc-tions, may be held stationary in any position by locking means, such as pins, studs, spring~biased locks, screws or other means.
Preferably, this cab is held stationary in the region of the two end faces of the vehicle so as to leave free a surface S which constitutes a platform for receiving various appliances such as sprayers, distributors, tanks, buckets, etc.
Further, in order to allow the operator to face always in the direction of the stretch of ground to be treated, the driving station 31 in this cab is mounted to be rotatable on a pivotal hub so that the whole of the station, including the control means, can pivot through at least 180.
~he connections between the various drivins means of the machine (Diesel engine, power take-off, pump coupling box) are achieved by elastic couplings allowing a disassembly of a single element of the transmission system in any region.
The machine according to the invention is so designed PO71~9~;3 as to be utilizable on any ground, including the road, since the front set of wheels can be declutched, and its utilization is greatly facilitated by the two independent drives for the sets of wheels located on each side of the chassis, since it is possible, by varying the deliveries of the pumps, to cause the vehicle to travel in one direction or the other or to obtain the locking of one series of wheels to obtain its skid-turning on the spot.
As concerns the steering, the wheels of the front and rear sets of wheels 4a, 4c are driving and steering wheels and the wheels 4b of the intermediate set of wheels are merely driving wheels.
The machine according to the invention has the following advantages:
- the machine can travel in both directions at any speed between O and 27 km per hour owing to the hydrostatic transmission;
- the items of equipment are identical in the front and at the rear so that it is possible to couple the tools - both to the front and to the rear of the machine;
- the stPering is effected on two axles, namely the front axle and rear axle, the centre axle remaining fixed, with the result that there is an improved turning circle.
The latter can be still further improved by skid-turning the machine by means of the hydraulic pumps;
- there is a differential locking on all the wheeLs in all conditions of use in a straight-ahead travel and when turning;
- the cab, located completely above the wheels, im-proves the front visibility. The cab may be advanced or shifted back, depending on the work to be carried out, .~
.
~76963 and the driver can choose the most suitable position;
- the driving station inside the cab can turn through 0 - 180 and assume any intermediate position;
- the machine is much more easy to handle than con-ventional tractors, since the transmissions are hydraulicand not mechanical.
The vehicle shown in Figs. 3 and 4 comprises a chassis 1 supported by two sets of driving wheels 102 and 103 and on which there is ~ixed a driving cab 104 enclosing the vehicle driving means and the means controlling the tools which may be coupled to two power take-offs 105 and 106 disposed respectively in the front and at the rear of the chassis.
The chassis lOl comprises, in the longitudinal direc-tion, two sections lOla and lOlb which are interconnected to pivot with respect to each other about a vertical axis X-X which is offset toward the front of the vehicle ~ith respect to the middle of the latter, that is to say, with respect to the transverse plane midway between the front and rear faces of the chassis.
The f-ont section lOla of the -hassis has a generally parallel-sided shape and is extended rearwardly by a portion 107a having a trapezoidal horizontal section, whereas the rear section lOlb also has a generally parallel-sided shape and is extended forwardly by an upper portion and a 25 lower portion 107b having a trapezoidal horizontal section.
These portion~ 107b terminate in forks 108 between which there are engaged brackets 109 which are integral with the portion 107a. These forks and brackets are pivotally interconnected by shaft portions 110. Two jacks 111 are 30 mounted on the front face of the parallel-sided portion . ~ . . .
'' , . ':
~07~963 of the section lOlb between the levels of the portions 107b so as to be disposed in the same horizontal plane and pivotable about vertical axes Y-Y located on said face.
The ends of their rods 112 are mounted in two forks 113, respectively fixed to each of the two sides of the chassis portion 107a, to pivot about vertical axes Z-Z. It is essential to note that the general pivot axis X-X of the chassis is disposed in a transverse plane of the vehicle located practically at the rear of the front set of wheels 102. The chassis 101 is completed by an upper platform 114 which covers the entire area of the rear section lOlb and extends forwardly beyond this part in overhanging relation to above the middle of the front set of wheels 102, this overhanging part carrying the cab 104 in the position for normal travel o~ the vehicle.
Such a pivoted arrangement of the chassis permits reducing to the maximum extent the gap between the latter and the wheels, so that it is possible to locate therein devices which are larger than in a rigid chassis. Indeed, a rigid cilassis must provide a sufficient clearance between , the wheels and the chassis to permit a suitable steering angle of the steering wheels. The gain as concerns the turning circle is between 20 and 30%. The offsetting of the pivotal connection in the direction of the-front set of wheels above all permits a solution of the problem of the steerability of the machine in rows of plants. Indeed, the inclination of the front section of the chassis through a small angle, for example 10 on each side of the median axis, has practically no effect on the performance of the tools which may be coupled to the rear of the vehicle.
-- ~ _ ~0~7ti9~3 The pivotal connection of the chassis is distinctly simpler, from the structural point of view, than the complex pivotal connection of steering wheels. It very definitely simplifies the supply of fluid to the driving wheels, each of which, as mentioned hereinafter, are driven by a hydraulic motor 115, since these wheels become fixed in position on the chassis.
This results in a considerable reduction in the cost of the vehicle and a most appreciable mechanical simplification.
In addition to the hydraulic motors 115 which are iO integral with the front wheels 102 and drive the latter, and the front power take-off 105, the front section 101a of the chassis carries two batteries 116 and a cooling device 117.
Likewise, apart from the hydraulic motors 115 integral with and driving the rear wheels 103 and the rear power take-off 106, the rear section lOlb of the chassis carries a drive unit constituted by an internal combustion engine 118 whose crankshaft is coupled to the input of a coupling box 119 which has three outputs respectively connected to ~0 a variable delive~y and xeversible hydraulic pump 120 ~or dri~ing the power take-offs and to two units having a single driving shaft each unit being constituted by a variable delivery and reversible hydraulic pump 121a or 121b for driving the hydraulic motors 115, a booster pu~p 122, a hydraulic pump 123a or 123b for driving the raising devices described hereinafter and, on one side, a pump 124a driving the hydraulic motor of the fan of the cooling device and, on the other side, a pump 124b actuating the jacks 111.
As shown in more detail in Fig~ 5, each of the hydraulic power take-offs 105 or 106 comprises a case 125 within which ., ) .~
_ ~g _ . _ .. . . . .
~-7~9~
there is disposed a speed-reducing train of gears 126 the input of which is integral with the shaft of a hydraulic motor 127, whereas the output is constituted by a hollow sleeve 128 which receives, in two coaxial stepped bores of different diameters, the central splined part of a power take-off shaft 129, the latter being fitted in corresponding splines of the associated bore, and one of the splined ends 129a of this shaft, the other splined end 129b of the latter projecting from the sleeve 128 for connection to a tool to be driven. One of the ends 129a and 129b of the shaft has a small number of splines, for example six, whereas the other has a larger number of splines, for example twenty-one, so that, depending on which end is disposed inside the sleeve, the tool can be driven at two different speeds.
Thus, for example, if the speed of rotation of the motor t 127 is 3000 rpm, the utilizable end of the power take-off shaft can drive the tool at 540 rpm or 1000 rpm.
As shown in Fig. 6, the two outputs of the reversible pump 120 are connected by pipes 130a and 130b respectively to two inputs of the motors 127 for driving the power take-offs, whereas the other two inputs of these motors are interconnected by a third pipe 130c, the assembly thereby constituting a closed pipe circuit. Two electro-hydraulically actuated hydraulic distributor valves 131a and 131b are interposed, one, between the pipes 130a and 130c and, the other, between the pipes 130b and 130c so as to permit supplying fluid to one or the other of the motors 127 or to both at the same time.
The circuit further comprises two pipes 132a and 132b branch connected to the pipes 130b and 130c between the distributor valve 131b and the motor 127 and connected to ~0769t;3 the inputs of an auxiliary hydraulic motor 133 which is adapted to drive one of the tools 133a with which the vehicle is provided, these pipes 132a and 132b having check valves 134 which allow the passage of the fluid only in the direc-tion of the motor. Stop valves 135 are inserted in thepipes 130b and 130c between the motor 127 and the branch connections of the pipes 132a and 132b.
The pump 120 is supplied with oil, as are moreover the pumps 121a and 121b, from an oil tank 13~ which is fixed outside on one of the sides of the section 101b of the chassis in front of the rear wheel 103. A fuel tank 137 for supplying fuel to the engine 118 is disposed symmetric-ally on the other side of this section.
This circuit drives the front and rear power take-offs 105 and 106 either individually or simultaneously in one direction or the other and at a variable speed which may reach either of the aforementioned two values, the two power take-offs necessarily rotating at the same speed when they are employed simultaneously owing to the use of a - 20 hydraulic control circuit in series.
Such a power take-off driving circuit has the great interest of taking advantage of the presence of a central hydraulic drive for the vehicle constituted by the engine 118, the box 119, the pumps 121a and 121b and-the motors 115 so as to provide a hydraulic power transmission with no difficulty. Such an arrangement uses the same oil tank, the same cooling device and the same filtering means as those already existing in the vehicle drive device.
In addition to the simplicity of construction of this power take-off drive circuit, there is an excellent utili-zation of these power take-offs owing to the extreme : ~
107~9~;3 flexibility of use of its component parts and in particular the variable delivery pump.
The vehicle further comprises at each of its two longi-tudinal ends a hydraulic raising device 138 or 139, two of these devices being provided at each end, one on the left side and the other on the right side. As shown in Figs. 3 and 4, each of these four devices is disposed in a vertical plane parallel to the longitudinal median plane of the vehicle and is constituted by a lower arm 140, an upper arm 141, a stay 142, and a jack 143. The two arms 140 and 141 are mounted at one of their ends on the front face of the section lOla of the chassis to pivot about horizontal transverse axes and respectively in the lower region and upper region of this front face.
The stay 142 is pivoted, on one hand, to the other end of the arm 140 and, on the other hand, to the lower arm 141 in the vicinity of the other end of the lower arm 141, this end being adapted for the fixing of a tool.
The jack 143 is pivoted in the lower region of the
2~ front face of the chassis and its upwardly extending rod is pivoted to the arm 140 in the vicinity of the end of the arm 140 which receives the stay 142.
As shown in Fig. 7, the device actuating such a raising device 138 or 139 comprises, on one hand, a displacement sensor 144 disposed above the upper arm 140 and actuated by the latter in accordance with its displacement, and on the other hand, a pressure sensor 145 inserted in a pipe 146 which connects either of the pumps 12la and 121b to the hydraulic motors 115 of the wheels. The sensor 144 is connected to one of the inputs of an amplifier 147 control-ling the position of the raising device, and the sensor 145 .. . ~ . . . . ..
~7~
is connected to one of the two inputs of another ~mplifier 148 controlling the force applied to the tool, the other input of the amplifier 147 being connected to a slide of a potentiometer 149 controlling the position and the second input of the amplifier 148 being connected to the slide of a second potentiometer 150 controlling the force, these two potentiometers being disposed in the cab so as to allow the driver to regulate them.
The two outputs of the amplifiers 147 and 148 are cannected to the electric control input of a hydraulic distributor valve lSl which is actuated electro-hydraulically and has an input connected to the corresponding raising pump 123a or 123b and two outputs, one of which outputs is connected to the fluid supply of the jack 143 and the other is connected to the oil tank 136.
! The pressure sensor 145 delivers a voltage which is proportional to the pressure of the fluid fed to the motors 115 driving the wheels and therefore proportional to the force of resistance applied to these wheels on the part of the tools carried by the vehicle which are either pushed along, if they are secured to the front raising devices ; 138, or towed if they are secured to the rear raising de-vices 139. The value of this force is then compared in the amplifier 148 with the value that the driver fed into or set on the force control potentiometer 150. If the value given by the sensor is higher than that set by the driver, the control produces the opening of the distributor valve 151 so as to raise the arms and consequently relieve the towing or pushing force.
When the value given by the sensor once again reaches ~1 , the control value, the control produces the closure of the distributor valve. As the position chosen for the raising device is thus reached, it is the position control device 149 and the displacement sensor 144 which permit a regulation of the raising by bringing the latter constantly to the previously-determined position. The operation is of course symmetrical in the case where the value given by the sensor 145 is lower than the value set by the driver.
Such a control of the raising devices has the great advantage ofbenefittingfrom the presence of a hydraulic drive for driving the driving wheels, in that the force applied to the tools is taken directly from the oil pressure prevailing in the oil supply circuit for the driving motors.
_ ~ _
As shown in Fig. 7, the device actuating such a raising device 138 or 139 comprises, on one hand, a displacement sensor 144 disposed above the upper arm 140 and actuated by the latter in accordance with its displacement, and on the other hand, a pressure sensor 145 inserted in a pipe 146 which connects either of the pumps 12la and 121b to the hydraulic motors 115 of the wheels. The sensor 144 is connected to one of the inputs of an amplifier 147 control-ling the position of the raising device, and the sensor 145 .. . ~ . . . . ..
~7~
is connected to one of the two inputs of another ~mplifier 148 controlling the force applied to the tool, the other input of the amplifier 147 being connected to a slide of a potentiometer 149 controlling the position and the second input of the amplifier 148 being connected to the slide of a second potentiometer 150 controlling the force, these two potentiometers being disposed in the cab so as to allow the driver to regulate them.
The two outputs of the amplifiers 147 and 148 are cannected to the electric control input of a hydraulic distributor valve lSl which is actuated electro-hydraulically and has an input connected to the corresponding raising pump 123a or 123b and two outputs, one of which outputs is connected to the fluid supply of the jack 143 and the other is connected to the oil tank 136.
! The pressure sensor 145 delivers a voltage which is proportional to the pressure of the fluid fed to the motors 115 driving the wheels and therefore proportional to the force of resistance applied to these wheels on the part of the tools carried by the vehicle which are either pushed along, if they are secured to the front raising devices ; 138, or towed if they are secured to the rear raising de-vices 139. The value of this force is then compared in the amplifier 148 with the value that the driver fed into or set on the force control potentiometer 150. If the value given by the sensor is higher than that set by the driver, the control produces the opening of the distributor valve 151 so as to raise the arms and consequently relieve the towing or pushing force.
When the value given by the sensor once again reaches ~1 , the control value, the control produces the closure of the distributor valve. As the position chosen for the raising device is thus reached, it is the position control device 149 and the displacement sensor 144 which permit a regulation of the raising by bringing the latter constantly to the previously-determined position. The operation is of course symmetrical in the case where the value given by the sensor 145 is lower than the value set by the driver.
Such a control of the raising devices has the great advantage ofbenefittingfrom the presence of a hydraulic drive for driving the driving wheels, in that the force applied to the tools is taken directly from the oil pressure prevailing in the oil supply circuit for the driving motors.
_ ~ _
Claims (17)
1. A tractor vehicle, in particular for agricultural use, comprising a chassis having a longitudinal axis, at least a front set of driving wheel and a rear set of driving wheels supporting the chassis, a cab, means mounting the cab on the chassis and allowing the cab to travel from one end of the ve-hicle to an opposite end of the vehicle in a direction parallel to said longitudinal axis, an engine and power take-off means carried by the chassis, the power take-off means being for connection to tool means, first means for controlling the dri-ving and steering of the vehicle and second means for control-ling the tool means to the take-off means, the first and se-cond means being located inside the cab, two independent drive means, one of the drive means being drivingly connected to a pair of said wheels located on one lateral side of said longi-tudinal axis and the other of the drive means being drivingly connected to a pair of said wheels located on an opposite la-teral side of said longitudinal axis, transmission means dri-vingly connecting the engine to the two drive means, variator-inverter means included in the two drive means, whereby the engine is capable of driving selectively either of the drive means, both of the drive means at the same time in a symmetrical manner and in an unsymmetrical manner, means included in the two drive means for reversing the drive means so that the ve-hicle can be made to travel in two opposite directions, subs-tantially identical raising devices respectively mounted on the chassis at longitudinally opposed ends of the vehicle, a driving station located in the cab and mounted to pivot through at least l80° about a vertical axis relative to the chassis whereby, irrespective of the direction of travel of the vehicle, the operator of the vehicle can face and be close to the stretch of ground to be treated.
2. A tractor vehicle as claimed in claim 1, wherein each of the two independent drives comprises a variable deli-very hydraulic pump operating in a closed circuit, the two pumps being connected to two outputs of a coupling box which has a third output for a power take-off and an input for cou-pling to the crankshaft of an engine.
3. A tractor vehicle as claimed in claim 1, wherein each raising device is a hydraulic raising device and control means located in the cab are connected to control the hydrau-lic actuation of the raising device, each of which raising devices comprises two upper arms pivoted to the chassis and two lower arms, the two upper arms being integral with each other, a flexion bar fixing together the two lower arms and two stays pivotally interconnecting the two pairs of arms, a position sensor combined with the upper arms and a deformation sensor combined with the flexion bar, a position control device and a force control device being located in the cab and an electric control unit being respectively connected to the posi-tion control device and force control device and to the position sensor and the force sensor the control unit being capable of reacting as a function of signals furnished by said sensors and as a function of values fed into the position control de-vice and force control device.
4. A tractor vehicle as claimed in claim 1, compri-sing rails mounted on the chassis and extending in a direction parallel to said longitudinal axis and rollers carried by the cab and rollingly engaged on the rails, means for holding the cab in any chosen position on said rails, the size of the cab being such that positionning the cab at an end of the chassis makes available a loading platform.
5. A tractor vehicle as claimed in claim 1, wherein connections between different means for driving the vehicle are constituted by flexible pipes which are easily disassembled.
6. A tractor vehicle as claimed in claim 1, wherein there are three sets of said wheels, said front and rear sets of wheels forming driving and pivotable steering wheels and the third set of wheels being mounted on the chassis to remain pa-rallel to said longitudinal axis in plan, each independent driving means driving all the wheels located on the correspon-ding side of the chassis.
7. A tractor vehicle as claimed in claim 2, wherein its travelling speed is proportional to the deliveries of the pumps.
8. A tractor vehicle as claimed in claim 2, wherein the wheels of the front set of wheels can be declutched on the road.
9. A tractor vehicle as claimed in claim 2, wherein the pumps are controlled electrically at the driving station by pedal means and a steering wheel and are reversible so as to cause the vehicle to travel in either direction, each wheel being connected to its respective pump through a double capa-city hydraulic motor.
10. A tractor vehicle as claimed in claim 2, wherein the third output of the coupling box is connected to a third hydraulic pump which drives at least one hydraulic motor ac-tuating the power take-off.
11. A tractor vehicle as claimed in claim 10, wherein a speed reducer is interposed between the hydraulic motor actuating the power take-off and the power take-off.
12. A tractor vehicle as claimed in claim 10, wherein the third hydraulic pump drives at least one hydraulic motor actuating a tool provided for the vehicle.
13. A tractor vehicle as claimed in claim 3, wherein each of the two independent drives comprises a variable deli-very hydraulic pump operating in a closed circuit, the two pumps being connected to two outputs of a coupling box which has a third output for a power take-off and an input for cou-pling to the crankshaft of an engine, the vehicle further com-prising, in the vicinity of each of the front and rear sets of wheels, a hydraulic raising device comprising two upper arms pivoted to the chassis and two lower arms, the upper arms being connected to the lower arms by stays, a position sensor com-bined with the upper arms, and a pressure sensor is inserted in a hydraulic supply circuit for hydraulic motors driving the driving wheels, said two sensors being connected to an electric control unit to which control unit position control means and force control means located in the cab are also connected.
14. A tractor vehicle as claimed in claim 13, wherein the control unit comprises a position amplifier and a force amplifier and the position control means and force control means each comprise a regulating potentiometer.
15. A tractor vehicle as claimed in claim 13, com-prising a hydraulic distributor valve actuated by the control unit, which distributor valve controls jacks actuating the raising device.
16. A tractor vehicle as claimed in claim 3, wherein the chassis comprises, in the direction of said longitudinal axis, two chassis sections, and pivot means interconnecting the two sections for pivoting about a vertical axis which is offset toward the front of the vehicle with respect to the middle of the length of the vehicle so that one chassis section is longer than the other chassis section, said means mounting the cab on the chassis being mounted on the longer chassis section and extending beyond the longer chassis section to overhang the shorter chassis section.
17. A tractor vehicle as claimed in claim 1, wherein the front section is rotatable by means of at least one hydrau-lic jack secured to the rear section.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7603589A FR2340850A1 (en) | 1976-02-10 | 1976-02-10 | TRACTOR VEHICLE, ESPECIALLY FOR AGRICULTURAL USE |
| FR7700516A FR2376782A2 (en) | 1976-02-10 | 1977-01-10 | TRACTOR VEHICLE, ESPECIALLY FOR AGRICULTURAL USE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1076963A true CA1076963A (en) | 1980-05-06 |
Family
ID=26219291
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA270,816A Expired CA1076963A (en) | 1976-02-10 | 1977-02-01 | Tractor vehicle in particular for agricultural use |
Country Status (8)
| Country | Link |
|---|---|
| JP (2) | JPS52118728A (en) |
| BE (1) | BE851294A (en) |
| CA (1) | CA1076963A (en) |
| DE (2) | DE7740374U1 (en) |
| FR (1) | FR2376782A2 (en) |
| GB (1) | GB1575131A (en) |
| IT (1) | IT1071785B (en) |
| NL (1) | NL7701282A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4632194A (en) * | 1983-11-08 | 1986-12-30 | Stuart A. Averill | Self-propelled saverdrill |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5522291U (en) * | 1978-08-02 | 1980-02-13 | ||
| DE3128284C2 (en) * | 1981-07-17 | 1983-12-29 | Xaver Fendt & Co, 8952 Marktoberdorf | Commercial vehicle, in particular tractors that can be used in agriculture, construction and / or forestry |
| NL8200663A (en) * | 1982-02-19 | 1983-09-16 | Lely Nv C Van Der | TRACTOR FOR AGRICULTURAL PURPOSES OR THE LIKE. |
| GB2119327B (en) * | 1982-04-19 | 1985-10-16 | Sands Agricult Mach | Self-propelled crop spraying vehicle |
| DE3319191A1 (en) * | 1983-05-27 | 1984-11-29 | Carl Kaelble, GmbH, 7150 Backnang | RAILWAY UNDERGROUND VEHICLE |
| JPS59230871A (en) * | 1983-06-13 | 1984-12-25 | Honda Motor Co Ltd | Stride-over type six-wheeled travel vehicle |
| DE3604519A1 (en) * | 1986-02-21 | 1987-08-20 | Iseki Agricult Mach | ADJUSTMENT DEVICE FOR TILLAGE EQUIPMENT |
| JPH01123975U (en) * | 1988-02-16 | 1989-08-23 | ||
| GB8907972D0 (en) * | 1989-04-08 | 1989-05-24 | Mckeefrey Liam S | Vehicles |
| GB2292929A (en) * | 1992-06-30 | 1996-03-13 | Caterpillar Inc | Material Handling Machine |
| FR2704197B1 (en) * | 1993-04-19 | 1995-06-02 | Viti Label | Self-propelled device for growing plants arranged in rows. |
| GB2361673A (en) * | 2000-04-25 | 2001-10-31 | Joseph Carroll | Agricultural machine or vehicle with rail mounted cabin |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE841850C (en) * | 1950-06-06 | 1952-06-19 | Theodor Klatte Fa | Cargo vehicle or truck with drive wheels driven by fluid motors |
| GB760923A (en) * | 1953-07-13 | 1956-11-07 | Fuller Lucas & Company Ltd | Improvements in or relating to agricultural and like tractors |
| DE1811163U (en) | 1960-01-28 | 1960-05-12 | Horst Virgenz | DETACHABLE TABLE LEG FASTENING. |
| FR1362478A (en) * | 1963-03-05 | 1964-06-05 | Loire Atel Forges | Hydraulic travel assistance for tractor and trailer crew |
| JPS4941903B1 (en) * | 1969-05-30 | 1974-11-12 | ||
| JPS524058B2 (en) * | 1972-02-24 | 1977-02-01 | ||
| JPS5123779B2 (en) * | 1973-05-21 | 1976-07-19 | ||
| JPS5321771B2 (en) * | 1974-04-19 | 1978-07-05 |
-
1977
- 1977-01-10 FR FR7700516A patent/FR2376782A2/en active Granted
- 1977-01-28 GB GB350277A patent/GB1575131A/en not_active Expired
- 1977-02-01 CA CA270,816A patent/CA1076963A/en not_active Expired
- 1977-02-04 IT IT8332277A patent/IT1071785B/en active
- 1977-02-08 NL NL7701282A patent/NL7701282A/en active Search and Examination
- 1977-02-09 DE DE19777740374 patent/DE7740374U1/en not_active Expired
- 1977-02-09 DE DE19772705400 patent/DE2705400C2/en not_active Expired
- 1977-02-10 BE BE174820A patent/BE851294A/en not_active IP Right Cessation
- 1977-02-10 JP JP1401977A patent/JPS52118728A/en active Pending
-
1983
- 1983-05-24 JP JP7812383U patent/JPS5922063U/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4632194A (en) * | 1983-11-08 | 1986-12-30 | Stuart A. Averill | Self-propelled saverdrill |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5922063U (en) | 1984-02-10 |
| DE2705400A1 (en) | 1977-08-18 |
| NL7701282A (en) | 1977-08-12 |
| FR2376782A2 (en) | 1978-08-04 |
| JPS52118728A (en) | 1977-10-05 |
| FR2376782B2 (en) | 1981-05-22 |
| BE851294A (en) | 1977-05-31 |
| DE7740374U1 (en) | 1981-07-09 |
| DE2705400C2 (en) | 1983-10-13 |
| IT1071785B (en) | 1985-04-10 |
| GB1575131A (en) | 1980-09-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |