Refuse collection vehicle with disconnectable loading unit

Abstract: Refuse collection vehicle with a chassis (1) and a rear axle provided with rear wheels, a body (3) supported by the chassis for the accommodation of refuse, and a loading unit (4) at the rear side of the body. The body and the loading unit are provided with interacting connecting means (5,6) for connecting the loading unit to and disconnecting it from the body. The loading unit is also provided with several supporting legs (8,9,10), each forming a support point (8a,9a,10a) for supporting the disconnected loading unit on the ground, which supporting legs are movable between a bottom supporting position, in which the support points are situated in their lowest position, and a higher up driving position, in which the supporting legs are situated at a level above the ground which permits driving with the loading unit connected to the body. At least one of the supporting legs is preferably designed in such a way that when the loading unit is connected to the body and when said supporting leg is in the supporting position the support point formed by said supporting leg is situated substantially as far forward as possible until it is between the rear wheels of the vehicle.

Description: The present invention relates to a refuse collection vehicle with a disconnectable loading unit according to the preamble of claim 1. Such a refuse collection vehicle is known from, for example, DE 40 05 968. This known vehicle has an interchangeable container, a loading unit being connected at the rear side of the interchangeable container. At the underside, the loading unit is provided with four vertical supporting legs which can be slid in and out telescopically, by means of which legs the detached loading unit can rest upon the ground. In the case of the known vehicle the loading unit projects backwards fully behind the chassis of the vehicle, because the supporting legs have to be able to move vertically downwards and therefore have to be situated behind the chassis. This position of the loading unit is a disadvantage for the weight distribution of the vehicle and has an adverse influence on the driving characteristics of the vehicle. The object of the present invention is to provide a loading unit with supporting legs which can be situated as close as possible to the rear axle of the vehicle, so that the centre of gravity of the loading unit is also situated close to the rear axle of the vehicle, with the result that the weight distribution is more advantageous and the vehicle is more manoeuvrable. A further object of the present invention is to provide a loading unit with stable supporting legs which are reliably locked in their supporting position. Another object of the present invention is to provide for the supporting legs to be movable by means of a single common drive between the driving position and the supporting position. The present invention provides a refuse collection vehicle according to the preamble of claim 1, which is characterized in that a front supporting leg is swivellably fixed on the loading unit and can swivel between the supporting position and the driving position, and in that said front supporting leg is designed such that when the loading unit is connected and said front supporting leg is in the supporting position the support point formed by said front supporting leg is situated below the chassis and substantially between the rear wheels of the vehicle. The invention makes it possible for the front support point, or several front support points situated relatively close together, to be situated considerably further forward than is the case with the loading unit of the known vehicle. This shift forward of the front support point makes it possible to place the centre of gravity of the loading unit, and thus in practice the entire loading unit, closer to the rear axle of the vehicle than is the case in the known vehicle. Further advantageous embodiments of the refuse collection vehicle according to the invention are described in the subclaims and the description which follows with reference to the drawing, in which: Fig. 1 shows diagrammatically a side view of a refuse collection vehicle according to the invention with interchangeable container and a connected loading unit; Fig. 2 shows the vehicle of Fig. 1 when the loading unit has just been disconnected; Fig. 3 shows diagrammatically in side view the rear part of the vehicle in Fig. 1 with the supporting legs in the supporting position; Fig. 4 shows a view corresponding to Fig. 3 while the supporting legs are being taken to the driving position; and Fig. 5 shows a view corresponding to Fig. 4 at a later stage of taking the supporting legs of the loading unit into the driving position. Figure 1 shows in side view a refuse collection vehicle of the rear loader type. Said vehicle comprises a chassis 1 with a rear axle 2 provided with rear wheels. The chassis is equipped in the known manner for accommodating and carrying an interchangeable container 3 for refuse, which container is supported by the chassis 1. The vehicle also has a loading unit 4 at the rear side of the interchangeable container 3, the interchangeable container 3 and the loading unit 4 being provided with interacting connecting means, hooks 5 on the loading unit 4 and pins 6 on the interchangeable container 3, for connecting the loading unit 4 to and disconnecting it from the interchangeable container 3. In a particular embodiment the interchangeable container 3 is provided with so-called ISO corner pieces at the corner points, which corner pieces are provided with recesses and are generally known for containers for transporting goods. In that embodiment provision is made for the loading unit 4 to be provided with hooks or the like which act directly upon the ISO corner pieces of the interchangeable container. The loading unit 4 is provided with a container lift 7, by means of which refuse containers can be lifted off the ground and emptied into the loading unit 4. The loading unit 4 is also provided with means (not shown) for forcing the refuse deposited in the loading unit 4 into the interchangeable container 3 through an opening in the rear wall of the interchangeable container 3. The loading unit 4 is provided with a movable front supporting leg 8 and two movable rear supporting legs 9, 10, each of which forms a support point 8a, 9a, 10a respectively for supporting the disconnected loading unit 4 on the ground. In Figure 1 the supporting legs 8, 9, 10 are situated in their driving position at a height above the ground which is sufficient to allow the vehicle to be driven. In Figure 2 the loading unit 4 is disconnected from the interchangeable container 3 and the loading unit 4 is resting with the supporting legs 8, 9 and 10, which are in their supporting position, on the ground. For disconnection of the loading unit 4, the procedure here is as follows. The supporting legs 8, 9 and 10 are first moved from the driving position shown in Figure 1 to the supporting position shown in Figure 2 in a manner to be explained in further detail below. The support points 8a, 9a, 10a of the supporting legs 8, 9 and 10 are then situated several centimetres above the ground. The chassis 1 is subsequently lowered at the rear side by means of the air suspension system of the vehicle, so that the supporting legs 8, 9 and 10 go onto the ground. Now lowering the chassis 1 still further causes the pins 6, or the ISO corner pieces, to drop out from under the hooks 5, and the loading unit 4 and the interchangeable container 3 are no longer connected. By driving the vehicle forward, the situation in Figure 2 is reached. In Figure 2 the container lift 7 is in the position for emptying a refuse container into the loading unit 4. Another way of disconnecting the loading unit 4 is to tilt the interchangeable container 3 together with the loading unit 4 connected thereto by means of the tilting system of the interchangeable container 3, after the supporting legs 8, 9 and 10 have been taken into the supporting position, so that the supporting legs 8, 9 and 10 go onto the ground. Driving the vehicle forward then causes the interchangeable container 3 to move further backwards relative to the vehicle and to be lowered relative to the loading unit 4 standing on the ground. This causes the pins 6 to drop out again from under the hooks 5, and the loading unit 4 is disconnected from the interchangeable container 3. For a detailed description of the design of the supporting legs 8, 9 and 10 of the loading unit 4, referal is now made to Figures 3, 4 and 5. In Figure 3 the supporting legs 8, 9, 10 are situated in the supporting position, after the loading unit 4 has been connected and has been raised from the ground by means of the air suspension system of the vehicle. The loading unit 4 is in the same position as when it is ready for disconnection from the interchangeable container 3. The front supporting leg 8 is fixed to the underside of the loading unit 4 so that it swivels about a front swivel shaft 12 extending at right angles to the longitudinal axis of the vehicle, near the side of the loading unit 4 adjoining the interchangeable container 3. The front supporting leg 8, viewed in its supporting position, has a first part 13 which from the front swivel shaft 12 is directed obliquely downwards and backwards, and a second part 14 which is immovably fixed thereto and is directed forwards between the rear wheels. The front supporting leg 8 can be swivelled about the front swivel shaft 12 between the driving position shown in Figure 1, in which the first part 13 of the front supporting leg is substantially parallel to the bottom of the loading unit 4, and the supporting position shown in Figures 2 and 3. The design of the front supporting leg 8 is such that in the supporting position, and when the loading unit 4 is connected to the container 3, the support point 8a formed by said supporting leg 8 is situated below the rear part of the chassis 1 of the vehicle and substantially midway between the rear wheels, near the rear axle 2 of the vehicle. For the sake of clarity of the illustration, part of the rear wheels is omitted in Figures 3 and 4. The two rear supporting legs 9, 10 are situated at a distance from each other, virtually the width of the vehicle, on a common line at right angles to the longitudinal axis of the vehicle, so that only one is visible in the figures. The two rear supporting legs 9, 10 are rigidly connected to each other by means of a crossbar construction 16 and thus form one piece which can be moved as a unit, with two rear support points 9a, 10a for the loading unit 4 situated at a distance from each other. The rear supporting legs 9, 10 are fixed to the underside of the loading unit 4 in such a way that they can be swivelled about a common rear swivel shaft 15 which is situated at a distance behind the front swivel shaft 12 and extends at right angles to the longitudinal axis of the vehicle. The rear supporting legs 9, 10 can be swivelled between the driving position shown in Figure 1, in which the rear supporting legs 9, 10 from the swivel shaft 15 onwards point downwards virtually horizontally, and the supporting position shown in Figure 3, in which the rear supporting legs 9, 10 from the rear swivel shaft 15 onwards are directed backwards and downwards at a slight angle. The centre of gravity Z of the loading unit 4 is also indicated in Figure 3, and it can be seen that, viewed at right angles to the longitudinal axis of the vehicle, the front support point 8a is situated at a distance in front of the centre of gravity Z of the loading unit 4, and the rear supporting points 9a and 10a are situated at a distance behind the centre of gravity Z of the loading unit 4. It can further be seen in Figure 3 (and also in Figure 2) that the front support point 8a formed by the front supporting leg 8 situated in the supporting position, viewed at right angles to the longitudinal axis of the vehicle, is situated in front of the front swivel shaft 12. In this case the loading unit 4 is provided with a stop 17 which interacts with the front supporting leg 8 when said supporting leg 8 is situated in the supporting position, which stop 17 prevents a swivelling movement of the front supporting leg 8 which would naturally accompany the downward movement of the loading unit 4. This means that the stop 17 prevents the loading unit 4 from dropping down, without an additional locking of the front supporting leg 8 being necessary. It can also be seen in Figure 3 that the rear support points 9a, 10a formed by the rear supporting legs 9, 10 situated in the supporting position, viewed at right angles to the longitudinal axis of the vehicle, are situated behind the rear swivel shaft 15. Owing to the fact that the loading unit 4 is provided at a suitable point with a stop 18 belonging to the rear supporting legs 9, 10, which stop interacts with the rear supporting legs 9, 10 when said supporting legs 9, 10 are situated in the supporting position, it is ensured that the stop 18 prevents a swivelling movement of the rear supporting legs 9, 10 which would naturally accompany the downward movement of the loading unit 4 resting on the supporting legs 8, 9, 10. Here again, in principle, separate locking of the rear supporting legs 9, 10 in the supporting position is therefore unnecessary. The two support points 9a, 10a at the rear side of the loading unit 4 produce great stability of the loading unit 4 standing on the ground when the vehicle is reversed against the loading unit 4, in order to connect the loading unit 4 to the interchangeable container 3. As is generally known, an interchangeable container system comprises a transverse roller 20 in the centre at the rear side of the chassis 1 of the vehicle. When the support point 8a is taken to the position described above, the transverse roller 20 is in the way, and the front supporting leg 8 is therefore designed in a special way. This design of the front supporting leg 8 is such that the first part 13 consists of two bars situated at a distance from each other, each being fixed to the loading unit 4 by means of a corresponding hinge fastening which swivels about swivel shaft 12. The ends of said bars are interconnected by a crossbar 21. The second part 14 of the front supporting leg 8 is fixed in the centre of the crossbar 21. For the swivelling of the supporting legs 8, 9 and 10, one common swivel drive is provided in the form of a double-acting hydraulic cylinder 25, which produces a swivelling movement of the supporting legs 8, 9, 10 by way of a transmission mechanism yet to be explained. The cylinder 25 is fixed by its one end to the loading unit 4 near the first swivel shaft 12, in such a way that it can be swivelled about a shaft 26 situated parallel to the front swivel shaft 12. The piston rod end of the cylinder 25 is connected to one end of an auxiliary rod 28 in such a way that it can be swivelled about shaft 27 running parallel to shaft 12, which auxiliary rod 28 is connected to the front supporting leg 8 by its other end, in such a way that it can swivel about shaft 29 running parallel to shaft 27. The cylinder 25 is situated above the crossbar 21, while the shaft 29 is situated at the opposite side of the crossbar 21. A connecting rod 30 is also provided, being connected by its one end to the auxiliary rod 28 in such a way that it can be swivelled about shaft 31, parallel to shaft 29, between the shafts 27 and 29 of said auxiliary rod 28. The other end of the connecting rod 30 is connected to the crossbar construction 16 in such a way that it can be swivelled about shaft 32, parallel to shaft 31, between the two rear supporting legs 9, 10. The assembly of cylinder 25, auxiliary rod 28 and connecting rod 30 ensures that the front supporting leg 8 and the rear supporting legs 9, 10 swivel together from the driving position to the supporting position, and back again to the driving position. In particular, it is ensured that when the piston rod of the cylinder 25 is retracted, in order to swivel the supporting legs 8, 9, 10 from the supporting position to the driving position, the auxiliary rod 28 first swivels about shaft 29 relative to the first supporting leg 8 until the auxiliary rod 28 comes to rest against the crossbar 21, during which swivelling of the auxiliary rod 28 the connecting rod 30 produces swivelling in the direction of the driving position of the rear supporting legs 9, 10, until they are virtually vertical, while the front supporting leg 8 remains in the supporting position on account of its own weight. This position of the supporting legs 8, 9, 10 is shown in Figure 4. On further retraction of the piston rod of the cylinder 25, both the first supporting leg 8 and the rear supporting legs 9, 10 swivel to their driving position, as can be seen from the illustration of Figure 5. In Figure 5 the front supporting leg 8 no longer lies against the corresponding stop 17 of the loading unit 4. On yet further retraction of the piston rod of the cylinder 25, the driving position of the supporting legs 8, 9, 10 shown in Figure 1 is reached. When the supporting legs 8, 9, 10 are being taken from their driving position to the supporting position, the piston rod of the cylinder 25 is extended and the movements described with reference to Figures 3, 4 and 5 occur in the reverse order. Hydraulic valve means (not shown), in particular non-return valves which are operated by a control pressure and are fitted at the connections of the two hydraulic lines on the cylinder 25, ensure that the cylinder 25, in any case in the extended position of the piston rod, is hydraulically secured against retracting so long as no hydraulic fluid is supplied to the cylinder 25 in order to move the supporting legs to their driving position. This means that the supporting legs 8, 9, 10 are locked in the supporting position not only by the arrangement of the corresponding stops described earlier, but also by the fact that the cylinder 25 is hydraulically secured. Further securing of the supporting legs 8, 9, 10 in their supporting position is obtained by the arrangement of the connecting rod 30. This will be explained with reference to Figure 4. If the cylinder 25 is not hydraulically secured or the corresponding valve means are not functioning, it is conceivable that the loading unit placed with the supporting legs on the ground will tilt backwards slightly and the supporting legs will go into the position shown in Figure 4. From that position, swivelling the rear supporting legs 9, 10 further towards the driving position would cause the connecting rod 30 to exert a moment on the front supporting leg 8, which moment would cause the front supporting leg to move even further in the direction of the supporting position. However, this movement of the front supporting leg 8 is impossible because said supporting leg 8 is already resting against the stop 17, so that the rear supporting legs 9, 10 can also swivel at most to the position shown in Figure 4 if the cylinder is not secured. In that position the centre of gravity Z still lies within the zone formed by the supporting points 8a, 9a, 10a and the loading unit remains standing stably on the ground. If the front supporting leg 8 were to be pressed from the position shown in Figure 3 in the direction of its driving position, the connecting rod 30 would cause the rear supporting legs 9, 10 to be pressed more firmly against their stop 18. In this way the loading unit remains standing stably on the ground even if there is a backward load. For placing the loading unit 4 in a horizontal position on a surface which is not flat, provision can be made for the rear supporting legs 8, 9 to be operated independently of each other, for example by providing one of the rear supporting legs with its own drive.

Claims: Refuse collection vehicle with a chassis (1) and a rear axle provided with rear wheels, a container (3) supported by the chassis for the accommodation of refuse, and a loading unit (4) at the rear side of the container, connecting means (5, 6) being provided for connecting and disconnecting the loading unit, and the loading unit (4) being provided with several supporting legs (8, 9, 10) including a front supporting leg (8), each forming a support point (8a, 9a, 10a) for supporting the disconnected loading unit (4) on the ground, which supporting legs are movable between a supporting position, in which the support points are situated in their lowest position, and a driving position, in which the supporting legs are situated at a level above the ground which permits driving with the loading unit connected to the container, characterized in that a front supporting leg (8) is swivellably fixed on the loading unit (4) and can swivel between the supporting position and the driving position, and in that said front supporting leg (8) is designed in such a way that when the loading unit (4) is connected and when said front supporting leg (8) is in the supporting position, the support point (8a) formed by said front supporting leg (8) is situated below the chassis (1) and substantially between the rear wheels (2) of the vehicle. Refuse collection vehicle according to claim 1, in which, when the loading unit (4) is connected to the container (3) and the supporting legs are in the supporting position, the supporting legs (8, 9, 10) of the loading unit (4) form one front support point (8a) which is situated substantially on the central longitudinal axis of the vehicle, and at least two rear support points (9a, 10a) situated at a distance from each other and on either side of the central longitudinal axis. Refuse collection vehicle according to claim 1 or 2, in which the loading unit has one front supporting leg (8) which forms the front support point (8a), which front supporting leg (8) is fixed to the underside of the loading unit (4) so that it swivels about a front swivel shaft (12) extending at right angles to the central longitudinal axis of the vehicle, which front supporting leg (8), viewed in its supporting position, has a first part (13) which from the front swivel axis (12) onwards is directed obliquely downwards and backwards, and a second part (14) which is immovably fixed thereto and is directed forward between the rear wheels (2), so that the front supporting leg (8) can be swivelled from the supporting position to the driving position, in which the first part (13) of the front supporting leg (8) lies along the underside of the loading unit (4). Refuse collection vehicle according to claim 3, in which the loading unit has two rear supporting legs (9, 10) which are fixed to the underside of the loading unit (4) so that they swivel about a common rear swivel shaft (15) situated at a distance behind the front swivel shaft (12) and extending at right angles to the central longitudinal axis of the vehicle, which rear supporting legs (9, 10) can be swivelled between the supporting position, in which the rear supporting legs from the rear swivel shaft (15) onwards are directed substantially downwards, and a forward directed driving position, in which the rear supporting legs (9, 10) are situated below the loading unit (4). Refuse collection vehicle according to claim 3 and 4, in which, viewed at right angles to the central longitudinal axis of the vehicle, the front swivel shaft (12) is situated at a distance in front of the centre of gravity (Z) of the loading unit (4), and the rear swivel shaft (15) is situated at a distance behind the centre of gravity (Z) of the loading unit (4). Refuse collection vehicle according to claim 5, in which the front support point (8a) formed by the front supporting leg (8) situated in the supporting position, viewed at right angles to the central longitudinal axis of the vehicle, is situated in front of the front swivel shaft (12), the loading unit (4) being provided with a stop (17) which interacts with the front supporting leg (8) when said supporting leg (8) is situated in the supporting position, which stop (17) prevents a swivelling movement of the front supporting leg (8) which would naturally accompany the downward movement of the loading unit (4). Refuse collection vehicle according to claim 5 or 6, in which the support points (9a, 10a) formed by the rear supporting legs (9, 10) situated in the supporting position, viewed at right angles to the central longitudinal axis of the vehicle, are situated behind the rear swivel shaft (15), the loading unit (4) being provided with a stop (18) which interacts with the rear supporting legs (9, 10) when said supporting legs (9, 10) are situated in the supporting position, which stop (18) prevents a swivelling movement of the rear supporting legs (9, 10) which would naturally accompany the downward movement of the loading unit (4). Refuse collection vehicle according to claim 2, in which the rear supporting legs (9, 10) are immovably connected to each other by means of a crossbar construction (16). Refuse collection vehicle according to claims 3 and 4, in which for the swivelling of the supporting legs (8, 9, 10), one common swivel drive (25) is provided, which drive by way of a transmission mechanism (28, 30) produces a swivelling movement of all supporting legs (8, 9, 10). Refuse collection vehicle according to claim 9, in which the transmission mechanism comprises a connecting rod (30) which is connected by its one end to the front supporting leg (8) in such a way that it can be swivelled, and is connected by its other end to the rear supporting legs (9, 10) in such a way that the front supporting leg (8) and the rear supporting legs (9, 10) swivel together from the driving position to the supporting position, and back again to the driving position. Refuse collection vehicle according to claim 10, in which a swivelling auxiliary rod (28) is connected to the front supporting leg (8), which in turn is swivellably connected to the connecting rod (30) to the rear supporting legs (9, 10), the common drive (25) acting upon the auxiliary rod (28), in such a way that for swivelling the supporting legs (8, 9, 10) from the supporting position to the driving position the auxiliary rod (28) is first swivelled relative to the front supporting leg (8) until the auxiliary rod (28) goes against a corresponding stop, during which swivelling of the auxiliary rod (28) the connecting rod (30) produces swivelling of the rear supporting legs (9, 10) in the direction of the driving position, while the front supporting leg (8) remains in the supporting position, and the front supporting leg (8) and the rear supporting legs (9, 10) then swivel together to their driving position. Refuse collection vehicle according to one or more of claims 9 - 11, in which the swivel drive comprises a hydraulic cylinder fitted on the loading unit. Refuse collection vehicle according to claim 12, in which hydraulic valve means fitted on the loading unit are provided for operation of the cylinder, which valve means are designed to retain the cylinder hydraulically in its position corresponding to the supporting position of the supporting legs when the valve means are not in operation. Refuse collection vehicle according to one or more of the preceding claims, in which at least one of the supporting legs (8) is designed in such a way that in the supporting position of said supporting leg (8) the support point (8a) formed by said supporting leg (8) is situated in front of the loading unit (4).

Inventors: ELBRINK HEINRICH JOHANNES, ELBRINK, HEINRICH JOHANNES
Applicants: GEESINK BV, GEESINK B.V.
Application year: 1997
Main classification: B65F3
IPC codes: B65F3