FR2709711A1 - System for attaching a forklift to at least four attachment elements, cradle for attachment and corresponding forklift. - Google Patents

Abstract

The invention relates to a system for attaching a forklift (12) to the rear of a carrier vehicle (11), said carrier vehicle (11) comprising a first and a second sheath (14) in which each fork (15) of said lift truck (12) is capable of coming into engagement, said carrier vehicle (10) further comprising at least a third and a fourth locking and centering sheaths (16), and said lift truck (12) comprising at least two bolts (17) capable of engaging respectively in said third and fourth sheaths (16), so that said lift truck (12) is attached to said carrier vehicle (10) by at least four fastening elements (15, 17). Thus, the carriage (12) is fixed in a simple and secure manner, and the hooking and unhooking maneuvers are simplified. The invention also relates to the attachment cradles (11) and the lift trucks (12) of such a system.

Description

System for attaching a forklift to at least four elements

  hanger, corresponding cradle and forklift.

  The field of the invention is that of forklifts, and more specifically the transport of such carts at the rear of carrier vehicles, such as trucks. It is indeed useful, even necessary, in many applications to have a forklift to load and unload a truck. However, it is not always possible to permanently have a forklift in all places of loading and unloading (in

  especially when these are not known in advance ...).

  We therefore thought of associating a forklift with the truck. This trolley is conventionally used for handling operations, and is fixed to the rear of the

  truck when moving it.

  In known manner, the truck is in this case equipped with two longitudinal sleeves in which are housed the forks of the forklift. By actuating these forks in the direction of descent, it is then possible to lift the carriage, so that it no longer touches the ground. Such a technique is notably disclosed in British patent documents No. 529,605 and American

n 3,799,379.

  This known solution has many drawbacks, in particular with regard to the reliability and security of the attachment and the maintenance of the carriage to the truck. These are only ensured by the hydraulic mechanism of the forklift. A leak in this mechanism may result in a progressive lowering of the carriage, until it touches the ground. A larger breakdown can also cause the truck to fall directly. In any case, this may have

  serious consequences, especially when the truck is moving.

  More generally, the movements and jolts due to the movement of the truck, sometimes over several hundred kilometers, cause progressive movements of the truck, which can on the one hand disturb the driving of the truck, and

  on the other hand, again, cause the carriage to fall.

  To overcome this drawback, additional fixing devices are generally provided (chains, slings, etc.). However, these devices are found

very insufficient.

  We have also imagined equipping the truck with a removable support surface on which the forklift comes to rest. According to this technique, described in particular in French patent document No. 76 01424, the carriage is first of all mounted above the level of the removable support, in the same way as above. Then, the removable support is deployed under the carriage. Finally, the forklift is lowered so that it rests on the support. To ensure

  blocking, the carriage is pressed down, by lifting the forks.

  This technique offers greater security than the techniques previously described. However, it has many drawbacks. First, it requires an operator to stand under the truck and / or under the cart to maneuver the support surface. This operation is awkward (space is limited and not very accessible), difficult (especially when the system begins to age, it is clogged by the thousands of kilometers traveled by the truck and it is more or less deformed by the weight of the carriage), and dangerous (the operator having to maneuver under the carriage while the latter is only held by his forks). Furthermore, it remains insufficient to maintain the carriage, especially if it has faults in its hydraulic system. Indeed, if the hydraulic pressure decreases, the carriage is only carried by the support

  removable. This carriage will then move, and possibly fall.

  In addition, the positioning of the carriage on the support surface is never very precise. Indeed, the lateral position of the forks relative to the carriage is variable, and there is nothing to control the centering. This can introduce overhangs, which damage the carriage and / or support, and which can disturb

driving the truck.

  Another drawback of this system is that it occupies an important place under the truck, when it is in the folded position. Conventionally, the support surface must measure at least one meter to sufficiently support the cart. It therefore occupies a large volume under the truck, of the order of one meter long by one meter wide and a height of 50 centimeters. Some trucks cannot receive such equipment. Others require complex and costly adaptations. Finally, the assembly and disassembly operations of the carriage at the rear of the truck are not easy, especially when the user is alone. Indeed, it must first engage the forks of the carriage in the sleeves provided for this purpose, then lift the carriage by actuating the forks. Then, it must descend from the carriage (operation made difficult since the carriage is raised by several tens of centimeters compared to its usual height), then maneuver

  manually the support surface (with the disadvantages already mentioned).

  Finally, it must again go back on the carriage to control its removal on the support.

  The object of the invention is in particular to alleviate these various drawbacks

state of the art.

  More specifically, a first objective of the invention is to provide a system for hooking a forklift to the rear of a carrier vehicle which is safe and reliable, even when the hydraulic mechanism of the forklift

has failures.

  In particular, an object of the invention is to provide such a system which sufficiently maintains the carriage in the transport position without using hydraulic energy. In other words, the invention aims to remove

  any risk of loss of the truck during the movement of the carrier vehicle.

  Another objective of the invention is to provide such a system, which ensures precise and systematic positioning of the forklift, so as in particular to avoid any risk of overhang, of lateral protrusion of the carriage relative to

to the vehicle, ...

  The invention also aims to provide such a system greatly limiting the size under the carrier vehicle, thus facilitating its installation

  and allowing its use with a large number of types of vehicles.

  An essential objective of the invention is also to provide such a system offering great job security. In particular, the invention aims

  avoid the operator having to access under the vehicle and / or under the truck.

  Another object of the invention is also to provide such a system which is particularly simple, quick and safe to handle. In particular, an objective of the invention is to provide, in a preferred embodiment, such a system not requiring the operator to move the carriage during operations

hanging and stalling.

  These objectives, as well as others which will appear subsequently, are achieved according to the invention using a system for attaching a forklift to the rear of a carrier vehicle, said carrier vehicle comprising first and second sleeves in which each fork of said forklift is capable of coming to engage, said carrier vehicle comprising at least a third and a fourth locking and centering sleeves, and said forklift comprising at least two latches capable of come to engage respectively in said third and fourth sleeves, so that said forklift is hooked to said

  carrier vehicle by at least four hooking elements.

  In other words, the forklift is secured to the vehicle by at least four male elements (the two forks and the two locks) which are

  engaged in fixed complementary female elements of the vehicle.

  This is a completely new approach for those skilled in the art. The carriage is not held by a movable external element, such as a surface of

  support. On the contrary, it includes internally all the mobile attachment elements.

  ge, which facilitates and secures this attachment.

  In addition, this new solution ensures perfect lateral centering of the trolley. Indeed, the engagement of the locks is only possible in the position

  precise expected during system design.

  In addition, the latches once engaged ensure lateral immobilization

and perfect vertical.

  Preferably, said third and fourth sleeves form

  an angle with said first and second sleeves between 3 and 30.

  Thus, when the locks are engaged, the carriage is securely attached to the vehicle. It cannot come off accidentally, even in the event of a hydraulic problem. We understand that the angle between the sheaths of

  forks and locks prevents longitudinal movement of the carriage.

  Advantageously, said forklift further comprises at least one first substantially vertical guide and locking element, and said carrier vehicle comprises at least one second complementary guiding and locking element, said first guiding and locking element engaging in said second guide and locking element when said forklift, the forks of which are engaged in said first and second

  sleeves, is actuated upwards.

  These pairs of guide and locking elements, generally two in number, allow the operator to easily position the latches opposite the third and fourth sleeves. In addition, they cooperate in the safety of attachment, by further strengthening the lateral and longitudinal immobilization of the carriage. Advantageously, said first and second guide elements

  comprise respectively a male cone and a complementary female cone.

  According to a first preferred embodiment of the invention, said latches are moved hydraulically, using the available hydraulic energy

on said forklift.

  This solution is particularly advantageous, because it avoids any manual manipulation and allows the operator to carry out all the operations of

  hooking or unhooking without leaving the carriage seat.

  According to a second embodiment of the invention, said locks are

  moved manually. They are for example actuated from the rear of the carriage.

  It is therefore not necessary to bend under the vehicle or under the trolley.

  Advantageously, the system comprises at least one position sensor

  delivering at least end of travel information for said locks.

  Thus, the operator knows precisely that the operation is finished.

  The invention also relates to the attachment cradles of a system as described above, intended to be fixed to a carrier vehicle. Preferably, such a cradle comprises fixing means

  unlockable, so that it can be detached from said carrier vehicle.

  The invention also relates to forklifts of such a system, comprising at least two latches capable of coming to engage respectively

  in said third and fourth sleeves.

  Other characteristics and advantages of the invention will appear on

  reading of the following description of a preferred embodiment of

  the invention, given by way of illustration and not limitation, and of the appended drawings, in which: - Figure 1 represents a truck equipped with an attachment cradle according to the invention on the one hand, and a forklift equipped with attachment means of the invention on the other hand, in side view; - Figure 2 shows the truck and the forklift of Figure 1, when the carriage is hooked to the truck, still in side view; Figure 3 shows the attachment cradle of Figure 1, in perspective; - Figure 4 shows the hooking means of the forklift of Figure 1, in perspective; - Figures SA to 5C illustrate the successive stages of attachment

  of a carriage as shown in Figure 2.

  As illustrated in Figures 1 and 2, a truck 10 is equipped according to the invention with a cradle 11 intended to allow the attachment of the forklift

  12, for its transport (Figure 2).

  This cradle 11 is fixed to the chassis or to the plate 13 of the truck 10, in a fixed or removable manner. In the latter case, the cradle is advantageously of the type described in French patent No. 90 14865 in the name of the same applicant as the present application. The cradle 11 comprises two sleeves 14 (only one being shown) provided for receiving the forks 15 of the carriage 12. I also comprises, according to an essential characteristic of the invention, two complementary sleeves

  16 provided to each receive a lock 17 fitted to the carriage 12.

  When the carriage 12 is in the transport position, as illustrated in FIG. 2, the latches 17 are engaged in the sleeves 16. Thus, the carriage 12 is hooked to the truck 10 by four separate points (the two forks 15 and the

two locks 17).

  In order to prevent the carriage 12 accidentally detaching from the cradle 11, the sleeves 16 are slightly inclined downward, looking from the rear towards the front of the truck 10. Thus, the sleeves 14 and 16 are not parallel but form an angle for example between 3 and 30. The carriage 12 cannot therefore be separated from the cradle 11 without the latches 17 being removed.

  Note in Figure 1 that the size of the cradle 11 is very limited.

  In practice, its length L is of the order of 50 cm, which allows it to be installed on most chassis or truck platforms. It does not include any

  sliding element capable of increasing this size.

  Figure 3 shows the cradle 11 in perspective. B is in this preferred embodiment of the invention a removable cradle, capable of being

  attached to a truck by means of two quick coupling members 311 and 312.

  These two members 311 and 312 are fixed on plates placed projecting from a

transverse beam 32.

  The cradle comprises two longitudinal sleeves 331 and 332, of which

  the rear end is fixed to the transverse beam 32. These longitudi-

  nals 331 and 332 are horizontal, so that they are parallel to the plane of the

  truck bed. They are intended to receive the forks of the carriage.

  According to the invention, the cradle further comprises two other sleeves 341 and 342 intended to receive the latches. They are substantially inclined, so that the distance between the sleeves 331 and 332 on the one hand and the sleeves 341 and 342 on the other hand increases substantially from the rear of the cradle (corresponding to the

  vertical plane passing through beam 32) towards the front of the cradle.

  This cradle can for example be constructed as follows. Two vertical columns 351 and 352 are fixed under the transverse beam 32 by one of their ends. The other two ends are fixed to a lower transverse beam 36. The sleeves 341 and 342 are fixed to one of their ends

  simultaneously with the lower beam 36 and the columns 351 and 352 respectively-

  is lying. The other ends of the sleeves 341 and 342 are connected by a second beam 37, itself connected to the sleeves 331 and 332 by two elements

transverse 37! and 372.

  Finally, the cradle comprises two vertical elements 391 and 392 fixed under the beam 22 and carrying two female guide and locking cones 3101 and

  3102 whose role is explained below.

  Figure 4 shows a part of the front of the carriage 12 in perspective. The forks, in the high position, are not shown in order to facilitate the

  description of the new elements of the invention.

  This new elements include first of all locks 411 and 412 which

  can move in sheaths 42 provided for this purpose, fixed under the carriage.

  These locks are intended to engage in the sleeves 341 and 342 (Figure 3).

  Position sensors 431 and 432 allow in particular to detect the

  good positioning of the locks when hanging.

  Finally, substantially vertical male cones 441 and 442 are fixed to the supports 451 and 452 of the front wheels. They are intended to engage in cones

females 3101 and 3102 (Figure 3).

  Figures SA to 5C illustrate the principle of attachment of the carriage 12 to the

truck 10 according to the invention.

  Beforehand, and conventionally, the driver of the carriage 12 engages the forks 15 in the sleeves 14 (arrow 18, FIG. 1). Then, still in a conventional manner, it begins to lift the carriage 12 by commanding a

lowering movement of the forks.

  FIG. 5A presents a first new characteristic of the invention.

  The lifting operation is not carried out without checking the lateral position of the forks relative to the carriage. On the contrary, the operator precisely controls this position, so that the male cones 51 of the carriage engage in the female cones 52 of the cradle. This ensures the exact positioning of the carriage relative to the truck. Locking is not possible as long as the cones

  males 51 are not engaged in the female cones 52.

  This particular positioning is determined during the design so as in particular to balance the masses of the carriage and to avoid overhangs and

overshoot of template.

  FIG. 5B illustrates the situation when this engagement male cone / female cone is carried out. It can be seen that in this situation, these male / female cone assemblies 51, 52 perform two other essential functions, in addition to lateral guidance, namely additional locking, allowing even better immobilization of the carriage, and precise vertical positioning putting the

  locks 53 facing the sleeves 54.

  It then suffices, as illustrated in FIG. 5C, to engage the latches 53 of the carriage in the sleeves 54 of the cradle. In this situation, the carriage is immobilized by the combination of the forks 15 engaged in the sleeves 14, latches 53 engaged in the sleeves 54 and male cones 51 engaged in the

female cones 52.

  Advantageously, the engagement and disengagement of the latches 53 is done hydraulically, by exploiting the hydraulic energy available on the carriage. Thus, the operator can carry out all of the hooking and unhooking operations from his seat, without having to carry out any mechanical operation manually. Position sensors 55 (only one being shown) make it possible to

  detecting respectively the complete engagement and disengagement of the locks.

  They control the supply of an indicator light which indicates to the operator that the locking or unlocking is complete. This further increases security

  of the system, the locks not being liable to be only partially engaged.

  In a simplified embodiment, the movement of the latches can also be manual. In this case, the maneuver is a little more complex, but remains safe. Indeed, the operator does not need to slip under the truck or the cart, the locks being easily accessible. This maneuver is done for example at the rear of the carriage. Then just push or pull the

locks 53.

  The dropout is of course symmetrical to the hanging.

he

Claims (10)

  1. System for attaching a forklift (12) to the rear of a carrier vehicle (11), said carrier vehicle (11) comprising first and second sleeves (14; 331, 332) in which each fork (15; 411, 412) of said forklift (12) is capable of coming to engage, characterized in that said carrier vehicle (10) comprises at least a third and a fourth sleeve (16; 341, 342; 54) locking and centering, and in that said forklift (12) comprises at least two latches (17; 411, 412; 53) capable of coming to engage respectively in said third and fourth sleeves (16; 3419 342; 54 ), so that said forklift (12)   either attached to said carrier vehicle (10) by at least four hooking elements ge (15, 17).   2. attachment system according to claim 1, characterized in that said third and fourth sleeves (16; 341, 342; 54) form an angle with said   first and second sleeves (14; 331 332) between 3 and 30.   3. attachment system according to any one of claims 1 and 2,   characterized in that said forklift (12) comprises at least one first element (441, 442; 51) for substantially vertical guiding and locking and in that said carrier vehicle (10) comprises at least one second element (3101, 3102 ; 52) of complementary guidance and locking, said first element (441, 442; 51) of guidance and locking engaging in said second element (3101, 3102; 52) of guidance and locking when said forklift (12 ), whose forks (15) are engaged in said first and second sleeves (14; 331 332), is actuated upwards.   4. attachment system according to claim 3, characterized in that said first and second guide elements respectively comprise a male cone   (441 442; 51) and a female cone (3101, 3102; 52) complementary.   5. attachment system according to any one of claims 1 to 4,   characterized in that said latches (17; 411, 412; 53) are moved hydraulically-   ment, using the hydraulic energy available on said forklift (12).   6. attachment system according to any one of claims 1 to 4,   characterized in that said latches (17; 411, 412; 53) are moved manually- is lying.   7. attachment system according to any one of claims 1 to 6,   characterized in that it comprises at least one position sensor (431, 432; 55) delivering at least end of travel information of said latches (17; 411, 412; 53). 8. Hanging cradle (11; Figure 3) of a system according to any one   claims 1 to 7, intended to be fixed to said carrier vehicle (10).   9. Hanging cradle (11; FIG. 3) according to claim 8, characterized in that it comprises unlockable fixing means (311, 312), so   that it can be separated from said carrier vehicle (10).   10. Forklift (12; Figure 4) of a system according to any one of   Claims 1 to 7, characterized in that it comprises at least two latches (17;   411, 412; 53) likely to come to engage respectively in said third   and fourth sleeves (16; 341, 342; 54).