FR2566732A1 - DEVICE FOR TOWING A TOOL OR A MACHINE SUCH AS A SHOVEL BY A SMALL LIGHT TRACTOR - Google Patents

Abstract

A DEVICE FOR CONNECTING A TOOL 3 TO A TRACTOR 2 FOR TOWING PURPOSES IS MADE IN THE FORM OF A MOBILE CHASSIS ON WHEELS, HAVING A PLATFORM 8 WHICH CAN BE INCLINED TO ALLOW THE TRACTOR TO RUN ON THE PLATFORM AND THEREFORE CONSTITUTE A BALLAST FOR TOOL 3 WHILE IT IS WORKING. THE MOBILE CHASSIS 1 IS EQUIPPED WITH A DRAWBAR 10 FOR PULLING BY THE TRACTOR WHEN NECESSARY, A DEVICE 5 FOR MOUNTING THE TOOL 3 ON THE CHASSIS, AS WELL AS A DEVICE OF COUPLING 13 FOR THE TRANSMISSION OF DRIVING FORCE FROM THE PTO OF TRACTOR 2 WHEN IT IS PLACED ON THE PLATFORM 8.

Description

This invention relates to a pulling or towing device for

  connect a tool or machine such as an excavator to a tractor for towing purposes and which is also adaptable so that

  the implement can be mO from the tractor when necessary.

  With many conventional devices of this type, the implement is mounted on the rear of the tractor, being supported by means of a three-point hitch or the like, and being mO from the hydraulic system of the tractor. With such a device, the tractor must be heavy enough, not only to provide the necessary ballast for the tool when it is working, but also to compensate for the weight of the tool when it is mounted on the tractor, so as to avoid tilting

  tool-vehicle combination hazards during transport.

  In recent years many small, light tractors have been

  put into service for different uses on agricultural farms

  schools and by municipal or other services, but it has not

  It has so far not been possible to use these small tractors to carry and operate machines such as shovels, backhoes and trenching machines, because they are not heavy enough to perform the tasks.

functions mentioned above.

  One of the aims of the invention is to provide a device making it possible to pull a tool or a machine like those indicated above and to operate it by a small tractor.

lightweight.

  The invention starts from a pulling device in the form of a mobile chassis on wheels and forming a platform. According to

  the invention, such a device is characterized in that the platform

  form is capable of assuming a position enabling a tractor to be placed on the platform at a workplace, to constitute a ballast for the working tool, and in that the mobile chassis has a means carried by it for establishing a towing link with the tractor when necessary, mounting means arranged to allow mounting of a working tool on the movable frame, as well as coupling means for the transmission of the driving force, which is arranged for be coupled to a mechanism

  tractor PTO when it is carried by the platform

  form. In this way, the invention allows the use of a Light tractor which would not normally be able to carry or balance the weight of a tool - to operate and to tow a tool, as required, changing his position and

  its mode of operation in relation to the mobile chassis.

  Preferably, the mobile chassis is equipped with wheels near one end and has a ramp or similar device at its other end to facilitate movement of the tractor on

The platform.

  According to an alternative embodiment, the wheels are mounted on the chassis so that they can be moved along the latter between different positions of use. For this purpose, the wheels should be mounted on a transverse axle slidably mounted on frame rails. It is preferable to provide a locking mechanism allowing movement and

  locking the wheels in any of these positions.

  The coupling means for the transmission of the driving force preferably constitutes a sleeve intended to receive an additional element which is integral in rotation with a PTO shaft of the tractor; the sleeve should be conical and designed to receive a drive element having a complementary conical shape provided on the PTO shaft and establishing a friction connection with the sleeve. This

  provision allows automatic establishment of a coupling

  dragging between the sleeve and the PTO shaft, with a

  minimal intervention or no intervention by an operator.

  Other characteristics and advantages of the invention

  will emerge more clearly from the following description of a

  nonlimiting exemplary embodiment, as well as the accompanying drawings, in which: - Figure 1 is a schematic side elevation view of the device according to the invention when used in towing a working tool by a tractor; FIG. 2 is a view similar to FIG. 1,

  but showing the mobile chassis forming the device according to the

  vention at an intermediate stage between two uses; - Figure 3 is a view similar to Figures 1 and 2, but showing the device during work with the tool; - Figures 4 to 6 are views similar to Figures 1 to 3 of an alternative embodiment of the movable frame according to the invention, in different modes of use; and

  - Figures 7 to 9 are different views of a mechanism

  locking mechanism forming part of the chassis of FIGS. 4 to 6.

  FIG. 1 represents a pulling or towing device according to the invention in the form of a movable chassis, generally designated by the reference 1, which is coupled at the front to a tow tractor 2 and at the end behind which is mounted a working tool 3, shown here in the form

  of a classic shovel. The shovel has lower attachment arms

  laughers 4 fixed to support arms 5 of the chassis; the drawing shows only one of the arms 4 and one of the arms 5. The shovel also has an articulated upper bar 6 which is fixed to upper points of the support arms 5. The chassis has a platform 8 with wheels 9 rolling on the ground at one end and at the other end a drawbar 10 which allows the movable chassis to be connected in any conventional manner to the rear of the tractor 2. The drawbar is retractable, when it is not used, at a position where it is located under the platform 8. A ramp 11 whose purpose will be described later is provided

  - possibly retractable - at the front of the platform.

  The device according to the invention is represented in FIG. 1 in a towing mode making it possible to tow the working tool by means of the tractor to the desired place of use. After arriving at this place, the mode of use of the device changes to allow the tractor to act as ballast and to constitute a source of motive force for the tool. For this purpose, the drawbar 10 is detached from the rear of the towing vehicle and is retracted under the platform 8, as shown in FIG. 2. The platform can then take a position where it is supported by ramp 11 at a low angle with the

  ground, which allows the tractor to roll by the ramp on the platform

  form 8. The start of this operation is shown in Figure 2.

  Articulated lower bars of the tractor, one of which, designated by 12, is visible in the drawings, are brought from a rest position where they are inclined upwards and which is visible in FIG. 1 at a position of lowered use shown on

Figures 2 and 3.

  FIG. 3 shows the tractor after it has been placed on the platform 8 and immobilized by the attachment of the bars 12 to suitable attachment points on the support and fixing arms 5. The device has a coupling means for the transmission of the driving force, designated as a whole by 13, which comprises a sleeve 14 arranged to receive a friction cone 15 carried by the conventional PTO shaft 16 exiting the gearbox of the tractor. The sleeve 14 has a conical shape complementary to the interior and the ramp 11 will normally be equipped with guide rails or flanges to guide the wheels of the tractor in order to force the tractor to advance on the platform so that the cone 15 enters the sleeve 14 for the establishment of the required friction coupling. Normally, the sleeve 14 will also be connected to a hydraulic pump for supplying the various cylinders of

  the hydraulic power tool, according to a conventional arrangement.

  Once the cone 15 is fully engaged in the sleeve 14, the attachment of the lower bars 12 of the tractor to the support arms 5, as described in the foregoing, will keep the cone and the sleeve in drive connection. The cone or sleeve will

  normally endowed with a certain flexibility with a view to compensating

  sation of a possible Slight misalignment that may exist between them. Before the start of work with the tool, crutches 17 of the shovel, shown in the retracted position in FIGS. 1 and 2, are extended to the floor, as can be seen in FIG. 3, to relieve the wheels 9 at least a large part of the weight of the whole, as well as forces

  produced by the operation of the Tool.

  During this operation, as is apparent from what

  above and from the drawings, the weight of the tractor placed on the platform

  form 8 constitutes the necessary Ballast with respect to the forces produced by the operation of the tool; moreover, the tractor is also used as a source of motive power for the tool by the socket

  cone 15 in the sleeve 14.

  When the work is finished in one place, it is

  easy to release the tractor by detaching the bars 12 and the coupling

  step 13 for the motive force comes apart automatically when the tractor descends by the ramp onto the ground. The drawbar 10 can then be re-attached to the tractor, as shown in the

  Figure 1, for towing the tool to another place of use

  station. The variant embodiment shown in FIGS. 4 to 6 roughly corresponds to the embodiment described in the foregoing and uses as far as possible the same references as in FIGS. 1 to 3. The main difference with the previous embodiment is that the wheels 9 of the mobile chassis are now mounted displaceable along the chassis and lockable at different positions. In this example, the tool 3 occupies a fixed position relative to the chassis, but this is not compulsory. Figure 4 shows the towing mode where the bar 10 is connected to the tractor 2 as in Figure 1. In this use, the wheels 9 of the chassis are arranged at the far end of the chassis

  of the tow tractor, practically under Tool 3.

  This variant provides the additional possibility

  to tow the tractor / mobile chassis combination as a complete unit by means of a separate tractor vehicle 2A, the tractor 2 being placed for this purpose on the chassis platform, as can be seen in Figure 5. It it is thus possible to transport the assembly by road over long distances between different workplaces, not only avoiding wear and tear on the tractor but also using a tractor vehicle which can travel at a relatively high speed while reducing the

  minimum transport time and traffic congestion.

  For this mode of use, the wheels 9 are brought to an intermediate location between the end of the chassis carrying the tool and the end where the drawbar is located, so as to obtain

  a towing position with optimal balancing.

  In the working mode, visible in Figure 6, the stands 17 (not shown in Figures 4 and 5 for clarity) are extended to stabilize the tool and the wheels 9 are moved to the towing end of the chassis , in

  view of obtaining a balanced layout with a

  optimal increase in workloads applied by the tool.

  Figures 7 to 9 show a possible solution for sliding mounting of the wheels on the chassis. The wheels (not shown) are mounted in this case at the two ends of an axle 20 which carries two knives 21 each arranged around a beam 22 of the chassis so as to be able to slide along it. Each slide 21 is composed of two parts or elements 21A, 21B assembled by bolts 23 passing through ears 23A. The lower elements 21A are fixed to the axle, by screwing or welding for example, and have a general U shape with shorter outer branches 21C. These lower elements surround the two longitudinal members 22 of the chassis on the lower sides thereof, the external branches 21C being in contact with the external faces of the longitudinal members 22 and the longer internal branches being in contact with the internal faces of the longitudinal members. The upper elements 21B have a simple square shape and are each applied by a branch against the internal face of one of the beams 22, the other branch being in contact with the upper face of the beam. Axle 20 is thus supported

  on the side members so that they can be moved along them.

  To lock the axle in the required position of

  several predetermined positions corresponding to the modes of use

  sation described in the foregoing, The movable frame comprises a locking mechanism which has two opposite locking bars 25 each articulated on a lever 26 which is itself articulated on a fixed vertical support 27. A central control cam 28 is rotatably mounted on the support 27 and is connected to the levers 26 by connecting rods 29. A square control rod 30 is threaded into a hole of complementary shape to the cam 28 and is connected by a suitable linkage (not shown) to a handle suitably positioned for be operated by the driver. FIG. 7 shows the mechanism with the locking bars extracted or removed inside the internal faces of the side members 22, which allows the axle / wheel assembly to be moved along the chassis to the desired position. Holes are provided in the internal walls of the side members at the places suitable for the reception of the locking bars for the purpose of blocking the axle / wheel assembly in each of the positions mentioned. When the axle has been brought to one of these positions, the cam is turned to the position shown in FIG. 8, which causes the extension of the locking bars and their penetration into the appropriate holes, as shown, which blocks all

  axle / wheels in the relevant position on the chassis.

  Hoops can be provided at intervals on the platform 8, in a fixed or removable arrangement, and a transparent tarpaulin can be fixed on the hoops to allow the use of the device in rainy weather since the tractor

  would then be protected under the cover during such use.

  It is also possible to mount the tool on a trolley which is itself movable along the platform with the interposition of a rolling or sliding mechanism to facilitate movement. Alternatively, or in addition, the tool can be mounted on a turret or similar mechanism, so as to allow the tool to pivot relative to the platform, so that the tool could work at a point located next to the mobile chassis, which may be necessary for example when cleaning ditches. The invention is not limited to the embodiments described and those skilled in the art may make various modifications thereto,

  without going beyond its framework.

Claims (12)

  1. Pulling or towing device in the form of a mobile chassis on wheels and forming a platform, characterized in   that The platform (8) is capable of taking a per-   putting a tractor (2) on the platform at a work place, to constitute a ballast for the work tool, and in that the mobile chassis has a means (10) carried by it to establish a connection towing with the tractor (2) when necessary, a mounting means (5) arranged to allow the mounting of a working tool (3) on the movable frame, as well as a coupling means (13) , for the transmission of motive force, which is arranged to be coupled to a gripping mechanism   force (5) of the tractor (2) when it is carried by the platform shape (8).   2. Device according to claim 1, in which   the tool (3) is mounted at a fixed location on the movable chassis.   3. Device according to claim I or 2, wherein the tool (3) is mounted at the end of the chassis located opposite the means (10) for establishing the towing connection.   4. Device according to any one of the claims   previous, in which the chassis wheels (9) are mounted at a fixed position of the chassis.   5. Device according to claim 4, in which   the wheels (9) of the chassis are mounted near the tool (3).   6. Device according to any one of claims 1   3, in which the wheels (9) are mounted on the chassis so that they can be moved between different positions of use Along the chassis.   7. Device according to claim 6, wherein the wheels (9) are mounted on a transverse axle (20) slidably mounted on frame rails (22).   8. Device according to claim 6 or 7, wherein a locking mechanism is provided to allow movement   and locking the wheels (9) at any one of the different positions tions.   9. Device according to claim 8, wherein the locking mechanism comprises two locking bars   opposite (25) designed to cooperate with holes in the lanyards rons (22) of the chassis.   10. Device according to any one of the claims   previous, in which a retractable ramp (11) is provided on the chassis to facilitate the movement of the tractor (2) on the platform (8).   11. Device according to any one of the claims   above, in which the coupling means (13) for the transmission of the driving force has a sleeve (14) intended to receive a corresponding element (15) which is integral in   rotation with a tractor PTO shaft.   12. Device according to claim 11, in which the sleeve (14) has internally a conical shape for the reception of a drive element of corresponding conical shape.   secured to the PTO shaft.