APPARATUS FOR LOADING AND UNLOADING A VEHICLE PLATFORM

Abstract: Apparatus for loading and unloading an exchangeable platform (3), container or the like onto and off a tipping frame (2) of a vehicle (1), the rearward end of said tipping frame (2) being connected through a shaft to the vehicle frame (1) and said tipping frame being tiltable in relation to the vehicle frame by at least one cylinder/piston combination (4). The tip­ ping frame (2) comprises an endless chain (8) arranged to run around a motor driven chain wheel (6) at one end of the tip­ ping frame (2) and a chain wheel (7) of otherwise embodied wheel at the other end of the tipping frame, whereby a sep­ arate auxiliary tail (9) is connected with one end thereof to the endless chain (2) and with the other end thereof to a hook-­ shaped engaging member (10) designed to become engaged to the platform (3), container or the like. The engaging member (10) comprises a section having a ridge (20) which during unloading of the exchangeable platform (3), container or the like will become inserted between the link elements of the endless chain (8), such that during unloading the move­ ment of said endless chain is transferred through said inser­ ted ridge (20) of said section of the engaging member (10) onto said engaging member (10) and through said engaging tmember (10) onto the exchangeable platform (3), container or the like.

Description: The invention relates to an apparatus for loading and unloading an exchangeable platform, container or the like onto and off a tipping frame of a vehicle, the rearward end of said tipping frame being connected through a shaft to the vehicle frame and said tipping frame being tiltable in relation to the vehicle frame by at least one cylinder/piston combination, said tipping frame comprising an endless chain arranged to run around a motor driven chain wheel at one end of the tipping frame and a chain wheel of otherwise embodied wheel at the other end of the tipping frame, whereby a separate auxiliary tail is connected with one end thereof to the endless chain and with the other end thereof to a hook-shaped engaging member designed to become engaged to the platform, container or the like. The invention relates furthermore to an engaging member for application in such an apparatus as well as a tipping frame destined to be used in such an apparatus. An apparatus of this type is known from the Dutch patent NL-C-167,635. In this known apparatus the endless chain comprises an outwards protruding ridge which is connected to the endless chain at such a location that this ridge during the unloading of a platform, container or the like can cooperate with the hook-shaped engaging member to push the platform, container or the like off the tipping frame through said engaging member. A condition in this construction is that the length of the auxiliary tail is equal to the distance between the location where the auxiliary tail is connected to the endless chain and the location where the pawl is connected to the endless chain. A disadvantage of this apparatus is caused by the stretching, to which the auxiliary tail appears to be subjected during operation. Because of this stretching the auxiliary tail will gradually grow larger resulting into a situation in which the cooperation between said pawl and the hook-shaped engaging member becomes disturbed such that it becomes necessary to replace the auxiliary tail. During replacement of the auxiliary tail, irrespective of the reason why the tail is replaced, one has to pay attention to the location where the auxiliary tail is connected to the endless chain because the distance between this connecting location and the pawl, connected to the endless chain, has to be equal to the length of the auxiliary tail. This requires therefore a certain degree of accuracy and attention of the personnel carrying out the replacement and therefore is a source of errors and to be considered as a disadvantage. Furthermore it is impossible to connect the auxiliary tail to the endless chain at an arbitrary location. To start with the endless chain will have to be brought into a suitable position and this hampers the assemblage. In such an apparatus furthermore the pawl is in generally not embodied as a separate part, connected by means of separate mounting means to the chain, but will form an integral part of one of the link elements of the endless chain. The use of such special parts in a chain of which the other parts are standard components, is also considered a disadvantage. An object of the invention is now to eliminate these disadvantages at least partly. Said object is in agreement with the invention fulfilled in that the engaging member comprises a section having a ridge which during unloading of the exchangeable platform, container or the like will become inserted between the link elements of the endless chain, such that during unloading the movement of said endless chain is transferred through said inserted ridge of said section of the engaging member onto said engaging member and through said engaging member onto the exchangeable platform, container or the like. In this embodiment it is not necessary anymore to fix or integrate a pawl to the endless chain and when the auxiliary tail is replaced it is not necessary to pay attention to the location of the pawl. Within the scope of the invention the engaging member may comprise a fixed section with a protruding ridge preferably comprising a self-seeking nature, which ridge already during the loading operation will become inserted between the link elements of the endless chain. With such an embodiment a number of the above indicated disadvantages are eliminated, however, the stretching in the chain may lead to a situation in which already during the loading procedure the auxiliary tail will become slackened after the ridge is inserted between the link elements of the endless chain. If during the loading procedure the front end of the container, platform or the like becomes detached for a short time from the endless chain, a situation which is normal during the practical operation of the apparatus, then the weight of the container, platform or the like has to be carried suddenly by the auxiliary tail which is pulled taut with a jerk. This applies a heavy momentaneous load both on the auxiliary tail as on the endless chain and on the connection between both chains, which is considered a disadvantage. Also the wear of the ridge and of the link elements in between which the ridge becomes inserted will increase in case the length of the auxiliary tail is gradualy changing during operation because of said stretching phenomenon. Therefore it is within the scope of the invention preferred that said section of the engaging member is pivotably connected to the engaging member such, that the ridge is able to move between a position in which the ridge is inserted between the link elements of the endless chain and a position in which the link elements are free to pass said ridge. Further preferred embodiments and other details of the invention will be explained in the following with reference to the accompanying drawings. Figures 1-6 show a number of different stages during the loading of a container onto the tipping frame of a vehicle. Figures 7-10 show the position of a hook-shaped engaging member, the coupling means and the endless chain in a number of stages during the loading of the container. Figure 11 shows a perspective view of the engaging member and the connecting means in the embodiment of the Figures 7-10. Figures 12 and 13 show a number of stages during the removal of a container from the vehicle onto a trailer. Figures 14-17 show the position of the hook-shaped engaging member, the coupling means and the endless chain in a number of stages during the loading of a container using a second embodiment of the engaging member. Figure 18 shows a perspective view of the engaging member in the second embodiment. Figures 19 and 20 illustrate the functioning of the movable pawl in the engaging means during the loading of a container. Figure 21 shows a further developed variant of the second embodiment of the engaging member. As shown in the Figures 1-6 a tipping frame 2 is arranged onto the chassis 1 of vehicle. This tipping frame is near the rear edge of the vehicle chassis 1 rotatably connected to said chassis through a not illustrated shaft and can be brought into a tilted position by means of one or more cylinder/piston combinations 4. The tipping frame 2 comprises an endless chain 8 running around a chain wheel 6 at the front of the tipping frame and a chain wheel or otherwise embodied wheel 7 at the rear of the tipping frame. The chain wheel 6 at the front of the tipping frame 2 is driven by an hydraulic motor 5. It is remarked that instead thereof also the rear wheel 7 can be embodied as the driven wheel in which case the hydraulic motor has to be positioned near the rear of the tipping frame. At the point 12 a auxiliary tail 9 is connected to the endless chain. The other end of said auxiliary tail comprises a hook-shaped engaging member 10 which will be discussed in more detail. The engaging member 10 is destined to couple with one or more coupling elements 14, which for that purpose are mounted to the lower side of a platform, container or the like, and are indicated in the Figure with reference number 3. Before the specific embodiment of a number of parts of this whole apparatus, especially the embodiment of the hook-shaped engaging member, will be discussed in more detail, first of all the functioning of this apparatus during the loading procedure will be described. In Figure 1 the tipping frame 2 is tilted to an inclined position and the endless chain 8 is moved by means of the drive motor 5 to such a position that the engaging member 10 at the end of the auxiliary tail 9 reaches approximately to the ground at the height of the coupling element 14 of the container 3. Thereafter the vehicle is moved backwards over a short distance such that the engaging member 10 will become coupled to the connecting element 14. Thereafter the direction of movement of the hydraulic motor 5 is reversed and the container 3 will be pulled upwards, hanging onto the auxiliary chain 9, as is illustrated in Figure 2. The auxiliary chain 9 is embodied such that this chain is also guided by a roll or rolls 7 at the rear of the tipping frame 2. As a result thereof the front end of the container 3 will be pulled onto the tipping frame as is illustrated in Figure 3. For a suitable support of the bottom of the container preferably supporting rolls or guiding rolls 17 are present cooperating with parts of the bottom of the container. During the further movement of the endless chain 8 the container will be pulled further and further onto the tipping frame. Thereby the situation which is schematically indicated in Figure 4, may occur whereby the container only rests against the tipping frame near the rear edge thereof and has a position which is more inclined than the inclination of the tipping frame. Continued pulling movement will, because of displacement of the center of gravity, result into a lowering of the front edge of the container and the container will return back onto the tipping frame. The situation as illustrated in Figure 4 can be avoided by a further tilting movement of the tipping frame which, however, is not always possible. In Figure 5 the platform 3 is completely pulled onto the tipping frame and the coupling element 14 or another specifically destined element is moved underneath the locking hook 19 so that the platform is locked onto the tipping frame. Finally the tipping frame is moved backwards to the horizontal position by means of the cylinder/piston combinaton(s) 4 reaching thereby the ultimate situation schematically illustrated in Figure 6. Thereafter the container 3 can be transported by means of the vehicle. A first embodiment of the engaging member is illustrated in Figures 7 until 10 in which also the cooperation between this engaging member and the coupling element of the container is illustrated whereas Figure 11 shows a perspective view of the engaging member in the first embodiment thereof. In Figure 11 an embodiment of the coupling means 14 is illustrated attached near the lower front side of the platform 3. The coupling means 14 comprises in this embodiment two horizontally, preferably round rods 15, which are running parallel to the lower front edge of the platform 3 at some distance thereof and are connected to the platform 3 near said front edge. Between the opposed ends of the rods a space is left open in which a self-directing wedge-shaped section 13 of the hook-shaped engaging means may fall in. By means of this wedge the hook is manoeuvred into the correct position even in case the vehicle is not correctly aligned during the backwards movement thereof. Preferably the opposed ends of the rodsel5 are somewhat bevelled to improve the self-positioning function of the engaging member 10 in relation to the coupling means 14. The engaging member 10 itself consists in principle of two hook-shaped sections which through transversal sections are connected to each other and are maintained at a distance of each other. The already mentioned wedge-shaped element 13 forms part of or is connected to one of these transversal sections. This construction can in general be considered as a U-shaped construction and the intention thereof is that both hook-shaped side sections or side parts during operation become positioned at both sides of the endless chain, in other words, that the endless chain during operation becomes positioned within the internal space in the U-shaped hook 10. The engaging member 10 furthermore comprises circular guiding sections 16 cooperating with for instance the chain wheel 7 during the passage of this wheel. These guiding sections 16 can also cooperate with eventual further guiding elements positioned alongside the endless chain 8. In the embodiment of the Figures 7 until 11 the engaging member furthermore comprises a section 11 carrying at the end thereof the ridge 20. This ridge 20 is embodied such that it will fit in the intermediate space between the link elements of the endless chain 8 as will be described in the following. The section 11 is fixedly connected to the hook-shaped side sections or is integrally formed with these sections. Figure 7 illustrates the situation in which the engaging member 10 is positioned directly in front of the coupling element 14 of the container (the situation which is comparable with Figure 1). By moving the vehicle backwards the engaging member 10 will become coupled to the coupling means 14 and if thereafter the auxiliary chain 9 is pulled upwards then the engaging member 10 will take the position as illustrated in Figure 8. Both hook-shaped side sections engage each one of the rods 15 and the positioning wedge 13 is located between those rods. By pulling the auxiliary tail 9 further upwards by means of the endless chain 8 a situation will be reached in which the engaging member 10 will take a position onto the endless chain 8. Thereby the ridge 20 will become inserted into the intermediate space between two link elements of the endless chain as is illustrated in Figure 9. The shape of the ridge 20 has to be such that this ridge fits into the intermediate space which is left open by the shafts 22 respectively the opposed side plates 21 of the chain 8. The continuing movement of the endless chain 8 results finally in a positioning of the engaging member as illustrated in Figure 10 which position in relation to the chain 8 will be maintained during the further movement to the ultimate position illustrated in Figure 6. Figures 12 and 13 illustrate in which way by means of the apparatus according to the invention a platform, container or the like can be pushed off a vehicle for instance onto a trailer or onto the ground. Starting from the situation which is illustrated in Figure 6 the direction of movement of the motor 5 is reversed. Thereby the endless chain 8 will take the ridge 20 along to the right in the Figures and will move thereby the engaging element as well as the container, platform or the like in backwards direction (to the right in the Figures). The auxiliary tail 9 has no function during this operation. Only if the backwards movement is carried out with the purpose to push the container 3 from the vehicle onto the ground, whereby the tipping frame is brought into an inclined position, the situation as illustrated in Figure 4 may occur in which the tail 9 of course has a very clear function. If during the use of the engaging member 10 in the embodiment according to the Figures 7-11 the auxiliary tail is elongated as result of stretching, then it is not inconceivable that the ridge 20, irrespective of the self-seeking nature thereof, will not become inserted anymore into the intermediate space between the link elements of the chain 8, but will come to rest onto the link elements. The loading procedure is not hampered thereby. At the start of the unloading procedure the endless chain 8 will be set in motion so that the chain 8 is moving in relation to the engaging member 10 and already after a few millimetres the ridge 20 will become inserted into the intermediate space between the link elements of the chain 8 and said ridge will be taken along in the described way. However, this could be considered as a disadvantage. An embodiment not having this disadvantage is illustrated in Figures 14 until 18. Figures 14 until 17 illustrate this embodiment of the engaging member in the same stages as illustrated in Figures 7 until 10, whereas Figure 18 illustrates a perspective view of this second embodiment. In this second embodiment the engaging member comprises an elongated pawl 23 positioned between both hook-shaped side sections of the engaging member and connected through a transversal pivot shaft 24 to both side sections. The other end of the pawl 23 carries the ridge 20 which in the situation of Figure 14 extends in the same way as the ridge 20 illustrated in Figure 7. If during the loading procedure the ridge 20 becomes inserted directly into an intermediate space between the link elements of the chain 8, then there is, with reference to the functioning of the ridge 20 during the various stages of the loading procedure illustrated in Figures 14 until 17 no difference with the stages illustrated in Figures 7 until 10. If, however, the ridge comes to rest onto a part of the link elements and, notwithstanding the self-seeking character of the ridge, will not become inserted into an intermediate space, then because of the pivot shaft 24 the ridge 20 may carry out a rotational movement and may take the position as illustrated in Figure 19. The movable rotatable ridge 23 does not hamper the loading movement of the container in any way and cannot lead to any damage or wear both of the chain 8 as well as of the ridge 23 itself. At the start of the unloading procedure the chain 8 will be moved in relation to the engaging element 10, so that already after a mutual displacement of a few millimetres the pawl 23 will rotate around the shaft 24 whereby the ridge-shaped end 20 of this pawl will become inserted into the intermediate space between the link elements of the chain and will take the position as illustrated in Figure 20. A further anti-clockwise rotation of the pawl 23 is in this further embodiment of the engaging member prevented so that the engaging member in the same way as already is discussed with reference to Figures 7 until 11 is moved to the right as result of the cooperation between the chain 8 and the ridge 20, so that the container 3 is pushed off the vehicle.

Claims: Apparatus for loading and unloading an exchangeable platform, container (3) or the like onto and off a tipping frame (2) of a vehicle, the rearward end of said tipping frame being connected through a shaft to the vehicle frame (1) and said tipping frame being tiltable in relation to the vehicle frame by at least one cylinder/piston combination (4), said tipping frame comprising an endless chain (8) arranged to run around a motor driven chain wheel (6) at one end of the tipping frame and a chain wheel or otherwise embodied wheel (7) at the other end of the tipping frame, whereby a separate auxiliary tail (9) is connected with one end thereof to the endless chain (8) and with the other end thereof to a hook-shaped engaging member (10) destined to become engaged to the platform, container (3) or the like, characterized in that the engaging member (10) comprises a section (11; 23) having a ridge (20) which during unloading of the exchangeable platform, container (3) or the like will become inserted between the link elements of the endless chain (8), such that during unloading the movement of said endless chain is transferred through said inserted ridge (20) of said section (11; 23) of the engaging member (10) onto said engaging member and through said engaging member onto the exchangeable platform, container (3) or the like. Apparatus according to claim 1, characterized in that said section (23) of the engaging member (10) is pivotably connected to the engaging member such, that the ridge (20) is able to move between a position in which the ridge is inserted between the link elements of the endless chain (8) and a position in which the link elements are free to pass said ridge (20). Apparatus according to claim 2, characterized in that the engaging member (10) is substantially U-shaped and said section thereof is in general embodied as an elongated pawl (23) which is positioned between the legs of the U-shaped engaging member and whereof one end is through a transversal shaft (24) pivotably connected to the engaging member (10), whereas the other end comprises said ridge (20). Apparatus according to claim 3, characterized in that in the position, in which the ridge (20) is inserted between the link elements of the endless chain (8) said elongated pawl (23) defined an angle with that part of the endless chain (8) between said pawl (23) and the rear end of the tipping frame which angle is smaller than 90°. Apparatus according to claim 3 or 4, characterized in that in the position in which the ridge (20) is inserted between the link elements of the endless chain (8) said elongated pawl (23) has at the side thereof directed to the front side of the tipping frame, a weight element (25). Apparatus accordig to one of the preceding claims, characterized in that said section (11; 23) of the engaging member (10) comprises a number of ridges of which the mutual distance corresponds with the distance between the link elements of the endless chain (8) or a multiple thereof. Apparatus according to one of the preceding claims, characterized in that the ridge respectively one of the ridges is inserted between the link elements of the endless chain (8) approximately beneath the point of contact between the engaging member (10) and the platform, container (3) or the like. Apparatus according to one of the preceding claims, characterized in that the sides of the ridge (20) or ridges are rounded off to give said extending parts a self-seeking nature. Engaging member for application in an apparatus as described in one of the preceding claims, destined for loading and unloading an exchangeable platform, container (3) or the like onto and off a tipping frame (2) of a vehicle, the rearward end of said tipping frame being connected through a shaft to the vehicle frame (1) and said tipping frame being tiltable in relation to the vehicle frame by at least one cylinder/piston combination (4), said tipping frame comprising an endless chain (8) arranged to run around a motor driven chain wheel (6) at one end of the tipping frame and a chain wheel of otherwise embodied wheel (7) at the other end of the tipping frame, whereby a separate auxiliary tail (9) is connected with one end thereof to the endless chain (8) and with the other end thereof to said hook-shaped engaging member (10) destined to become engaged to the platform, container (3) or the like, characterized in that the engaging member (10) comprises a section (11; 23) having a ridge (20) which during unloading of the exchangeable platform, container (3) or the like will become inserted between the link elements of the endless chain (8), such that during unloading the movement of said endless chain is transferred through said inserted ridge (20) of said section (11; 23) of the engaging member (10) onto said engaging member and through said engaging member onto the exchangeable platform, container (3) or the like. Tipping frame destined to be used in an apparatus according to one of the preceding claims, comprising an endless chain (8) running around a motor-driven chain wheel at one end of the tipping frame and a chain wheel (6) or otherwise embodied wheel at the other end of the tipping frame, whereby a separate auxiliary tail (9) is with one end thereof connected to said endless chain (8) and with another end thereof connected to a hook-shaped engaging member, characterized in that the engaging member (10) comprises a section (11; 23) having a ridge (20) which during unlodading of the exchangeable platform, container (3) or the like will become inserted between the link elements of the endless chain (8), such that during unloading the movement of said endless chain is transferred through said inserted ridge (20) of said section (11; 23) of the engaging member (10) onto said engaging member and through said engaging member onto the exchangeable platform, container (3) or the like.

Inventors: VAN DEN POL, AART ANTONIE
Applicants: DE ARK B.V.
Application year: 1986
Main classification: B60P1
IPC codes: B60P1