FR3073810A1 - METHOD AND STATION FOR AUTOMATED LOADING OF ROOF TRAVERS ON A BOX FRAME OF A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a method of automatically depositing roof sleepers (4a-4c) on a body frame (1a-1c) at a loading station (3) comprising a single station (7) for laying the sleepers ( 4a-4c). The removal station (7) comprises a single store (8) for storing the sleepers (4a-4c) and a single manipulator (11) for gripping the sleepers (4a-4c), the implementation of which is placed under the control of control means (5). A first step is a step of collective gripping by the manipulator (11) of a set of crosspieces (4a-4c) stored in the storage magazine (8) and comprising a front cross member (4a), a crossbeam (4b) and a rear crossmember (4c). A second step is a step of successive deposition by the manipulator (11) of each of the crosspieces (4a-4c) previously entered, comprising operations of depositing at least two of the three crosspieces (4a-4c) on the reinforcement of body (1a-1c), including at least the rear crossmember (4c) and the front crossmember (4a), under control of the control means (5) according to the configuration of the body frame (1a-1c) to produce previously identified.

Description

METHOD AND STATION FOR AUTOMATICALLY LOADING ROAD CROSSINGS ON A BODY REINFORCEMENT OF A MOTOR VEHICLE.

The present invention relates to the field of motor vehicles and more particularly to the automation of shoeing operations on an assembly line of the components of a body frame of a motor vehicle. The invention relates more particularly to the automation of operations for removing roof sleepers on such a body frame.

Motor vehicles include a body frame covered with bodywork elements and arranged to form a rolling structure. The body frame provides a robust structure for the vehicle, on which various equipment is then installed, in particular to provide propulsion of the vehicle and / or to provide comfort to the passengers.

The body frame comprises various components which are assembled together in different successive work stations of an assembly line. Among its components, the body frame comprises a roof frame which is essentially composed of side members and cross members and which is configured to receive at least one panel providing a roof pavilion for the vehicle. The side members extend from front to rear and the cross members extend between the lateral sides of the body frame. The side members and the cross members are commonly arranged in arches, the side members then forming longitudinal roof arcs and the cross members then forming transverse roof arcs.

The roof may be formed by a solid panel installed fixedly on the body frame via the roof frame. The roof framework then typically comprises a set of three crosspieces including a front crosspiece, a central crosspiece and a rear crosspiece, as shown for example in document 2,921,038 (PEUGEOT CITROËN AUTOMOBILES SA).

The pavilion is also likely to include at least one panel which is provided with glazing and / or which is movably mounted on the roof framework between an open position and a closed position. In this case, the roof frame typically comprises a set of two front and rear crosspieces between which is installed a support frame for the panel, as shown, for example, from document 3,047,221 (PEUGEOT CITROËN AUTOMOBILES SA).

The longitudinal members and cross members of the roof frame are mounted on the body frame by being fixed to the top of uprights distributed longitudinally to the lateral sides of the body frame. A phase of removing the components of the roof frame on the uprights is then carried out on the assembly line of the body frame, prior to their attachment to each other and / or with reinforcing elements or dressing.

In this context, the assembly line of the body armature comprises several work stations arranged along a step-by-step routing line of body armatures to be produced successively. Essentially, the assembly line of the body frame successively comprises a station for loading the sides of the body and / or a rear panel, a station for loading the sleepers, then a station for shaping the body, in particular by providing a covering.

The sleeper loading station conventionally comprises crossover removal stations on the body frame. The various depositing stations include a manipulator and a storage warehouse for sleepers of a given type, that is to say sleepers of the front sleeper type, of the middle sleeper type or of the rear sleeper type. Such a segmentation of the various depositing stations facilitates the management of the order of depositing the crosspieces on the body frame. The deposition of the crosspieces on the body frame is controlled by a control means regulating the implementation of the manipulators according to a previously established deposit order.

Thus, the body frame is moved by the routing line successively to the depositing stations. A manipulator grabs a cross member at the storage warehouse assigned to it, then moves it to place it in its intended location on the box frame. The operation is repeated at each of the drop-off stations according to the order of deposit of the sleepers previously established.

In this context and on the basis of the observation which has just been made, the present invention is more specifically part of a search for a procedure for automating the operations of removing the sleepers on the body frame at the station. loading of sleepers.

Thus, the subject of the invention is an automated method of depositing on a body frame of a motor vehicle, sleepers that comprises a participating roof frame of the body frame. The invention also relates to a station for loading sleepers on the body frame that includes an assembly line for the components of the body frame.

An object of the invention is to limit the space occupied on the ground by the loading station for the sleepers on the body frame. It is finally sought to reduce the overall size on the ground of the assembly line comprising said loading station.

Another object of the invention is to arrange the loading station for the sleepers, so as to obtain sustained production rates for the body frames successively moved along the assembly line.

Another object of the invention is to simplify the organization of the sleeper loading station, in particular to limit its structural costs, its development costs inside a building housing the assembly line, and / or its implementation costs.

Another object of the invention is to allow a selective removal of the crosspieces on the body frames, taking into account a potential diversification of the architectures of the roof frames between the body frames successively moved along the assembly line .

Such a diversity of architectures of the roof frames in particular relates to roof frames comprising three crosspieces for the reception of a fixed roof panel, or roof frameworks comprising two crosspieces for the reception of a support frame of at least a glazed roof panel and / or at least one roof panel movable between an open and closed position.

It is in particular targeted by the invention a reduction in the production costs of the vehicle in the context of notoriously severe economic competition in the automotive field. Such cost reduction is particularly sought:

-) by increasing the production rates of body fittings,

-) by reducing the size of the loading station or in other words by optimizing the use of a surface which is sought as small as possible and which is reserved for the installation of the loading station inside a building housing the assembly line,

-) by simplifying the layout and / or organization of the loading station, as well as the methods of its installation along the line of routing of the body fittings, and / or

-) by optimizing the profitability of the loading station by making it versatile, in particular from a faculty of the loading station to selectively deposit sleepers on the body frames according to architectures of the roof frames which can be diversified.

The aims of the present invention are achieved individually or in combination by applying the following provisions.

The method of the invention is an automated method of depositing roof rails on a body frame at a participating loading station of an assembly line. The loading station is arranged along a step-by-step routing line of box frames to be produced successively.

The loading station comprises at least one station for depositing at least one cross member on the body frame. Said at least one depositing station comprises at least one storage store for at least one cross member and at least one manipulator for gripping said at least one cross member. The implementation of the manipulator is placed under the dependence of a control means causing in a first step an entry of said at least one cross member by the manipulator and in a second step a removal of said at least one cross member on the frame checkout.

According to the invention, said first step is a step of collective entry by a single manipulator of three sleepers of a set of sleepers stored in a single storage store in packets of said set of three sleepers. Each set of cross members includes a front cross member, a middle cross member and a rear cross member.

Said second step is a step of successive deposits by the manipulator of each of the previously entered sleepers. The second step includes operations for removing at least two of the three cross members on the body frame, including at least the rear cross member and the front cross member, under control of the control means depending on the configuration of the body frame. case to be produced previously identified.

If necessary, the notion of cross member as well as the rear, middle and front notions qualifying the sleepers, are relative concepts typically identified with regard to the longitudinal extension of the vehicle from front to rear.

The identification of the individual configuration of the body armatures successively displaced along the assembly line is for example conventionally carried out on the basis of an exchange of information between the control means and a means of individual identification of the body armatures. case to be produced successively. Such an identification can be carried out at the start of routing of the body frame by the assembly line and / or at the input of a work station which it comprises.

According to one embodiment, the second step more specifically comprises:

-) successive removal operations by the manipulator at least of the front cross member and the rear cross member on the body frame, and

-) an operation for depositing the middle cross member by the manipulator selectively as a function of the configuration of the body frame to be produced previously identified.

The operation of depositing the middle cross member is then:

-) or a removal operation of the middle cross member on the body frame, which is preferably carried out between the removal operations of the front cross member and the rear cross member,

-) Or an operation of depositing the middle cross member in a recovery tank, which is preferably carried out before, or even after, the operations of removing the rear cross member and the front cross member on the body frame.

According to one embodiment, the method comprises an operation of loading the magazine in packs of said sets of sleepers. The crosspieces of each of the packages are stored adjacent to the storage magazine in their main direction of extension, in a sequential order of storage of the middle crosspiece, the rear cross member and the front cross member. In addition, the first step is a step of collective entry of the sleepers by the manipulator according to said order of storage.

According to one embodiment, at the end of the first step and in the direction of collective entry of the crosspieces of a said set of crosspieces by the manipulator at the storage store, the crosspieces are carried by the manipulator according to an order of superposition . According to this order of superposition, the rear cross member is disposed at an upper plane of overhang of the central cross member and the front cross member, and the central cross member is arranged on a median plane of overhang of the front cross member which is arranged on a lower plane .

The invention also relates to a loading station for roof rails on a body frame suitable for implementing a method according to the invention. According to the invention, the loading station comprises a said deposit station which is unique and which comprises:

-) a single so-called storage store for sets of sleeper sets, each comprising three sleepers including a rear crossmember, a middle crossmember and a front crossmember, and

-) a single manipulator for collective entry of the sleepers of a said set of sleepers and of successive individual deposits of the sleepers at said single drop-off station.

According to one embodiment and for each of the packages of said sets of sleepers, the storage magazine comprises individual supports for the sleepers in respective predefined positions relative to each other. Said supports are each provided with at least positioning members of the sleepers which are assigned to them.

According to one embodiment, the manipulator is equipped with a collective gripping head of the sleepers of a said set of sleepers. The gripping head comprises individual gripping heads for the sleepers in respective predefined positions relative to each other, in correlation with the respective positions at least adjacent to the sleepers in the storage magazine.

According to one embodiment, the gripping head is provided with a member for joining the manipulator in a direction of assembly between them, in particular a direction in elevation. The gripping head is also provided with a support beam adjacent to the gripping heads, the beam being oriented perpendicular to said direction of assembly and perpendicular to a main direction of extension of the gripping heads oriented in the direction of main extension of the sleepers assigned to them. In other words, the direction of assembly between the gripping head and the manipulator, the orientation of the beam and the direction of extension of the gripping heads parallel to each other, are perpendicular to each other in an orthonormal reference frame.

The gripping head is preferably arranged in a stepped structure successively comprising the joining member, the beam carried by the joining member, and all of the gripping heads individually mounted on the beam parallel to each other. According to a variant, the gripping head is arranged in a stepped structure successively comprising the joining member, the beam carried by the joining member, and all of the gripping heads carried by the beam parallel to each other, l at least one of the gripping heads being carried by any at least of the other gripping heads. In other words, according to this variant, at least one of the gripping heads carries another gripping head interposed adjacent between the two other gripping heads, via at least one arm connecting them together.

According to one embodiment, said beam forms a support for a control-command member for the individual implementation of each of the gripping heads. The implementation of the control command is placed under the dependence of the control means. The beam is preferably hollowed out by housing means for transmitting energy, electrical, pneumatic and / or hydraulic, connecting the control-command member and members equipping the gripping heads, such as for example at least one clamping member and / or at least one detector for the presence of crosspieces on the gripping head.

Preferably, each of the gripping heads is equipped with:

-) at least one positioning member on the gripping head of the crosspiece which is assigned to it,

-) at least one clamping member of said crosspiece which is assigned to it,

-) at least one support member of said crosspiece which is assigned to it against the gripping head, and

-) At least one presence detector on the gripping head of said crosspiece which is assigned to it.

Examples of embodiments of a loading station and / or of its components in accordance with the present invention will be described in relation to the figures of the appended plates, in which:

-) Figure 1 is a schematic illustration of a sleeper loading station on a frame of a motor vehicle body according to an exemplary embodiment of the invention, which is arranged along a step-by-step routing line of a series of box frames to be produced.

-) FIG. 2 is a partial diagrammatic illustration in side view of an exemplary embodiment of a sleeper storage store configured to equip the loading station shown in FIG. 1,

-) Figure 3 and Figure 4 are schematic illustrations respectively in side view and in bottom view, of an embodiment of a gripping head of the sleepers configured to equip a single manipulator that includes the loading station shown in Figure 1,

-) Figure 5 and Figure 6 are partial perspective illustrations of an embodiment of a sleeper storage store configured to equip the loading station shown in Figure 1, respectively shown empty and shown loaded d 'a set of sleepers.

-) Figure 7 and Figure 8 are partial illustrations in perspective from respective points of view, of an exemplary embodiment of a gripping head of the sleepers configured to equip a single manipulator that includes the loading station shown on Figure 1,

-) FIG. 9 and FIG. 10 are partial illustrations in perspective of the gripping head shown in FIGS. 7 and 8, in a situation of gripping the sleepers previously picked up from the storage magazine shown in FIGS. 5 and 6.

-) Figures 11 to 16 are perspective views illustrating an example of implementation of a method according to the invention.

The figures and their detailed descriptions show the invention according to particular methods which are not restrictive as to the scope of the invention as defined by the claims. The figures and their detailed descriptions can be used to better define the invention, if necessary in relation to the general description which has just been made.

In Figure 1, an assembly line is organized to produce body frames 1a, 1b, 1c for motor vehicles. The assembly line comprises a routing line 2 step by step of the box frames 1a-1c to various work stations installed successively along the route line 2. The box frames 1a-1c are thus moved step by step along a direction S1 of advancement towards the workstations, for gradually assembling the components of the box frames 1a-1c at each advancement step.

Among said work stations, the assembly line comprises a loading station 3 of sleepers 4a, 4b, 4c on the body frames 1a-1c. The crosspieces 4a-4c are selectively assembled on the box frames 4a-4c via uprights and / or side rails previously mounted on the box frames 1a-1c, such as for example the uprights 22a or the side rails 22b which are visible in FIGS. 11, 13, 14 and 15. The crosspieces 4a-4b constitute a roof frame of the body frames 1a-1c which is designed to subsequently receive at least one panel forming a roof pavilion.

The assembly line comprises at least one control means 5 for regulating the various automata to be used to form the box frames 1a-1c according to their own arrangement. The control means 5 is equipped with a memory 6a for the individual identification of the lay body frames according to their architecture. Such an identification is notably carried out by exchanges of information between an identification member 6b of the body fittings 1a-1c and the control means 5.

In the context of the invention, the differentiation between the architectures of the body frames 1a-1c relates to the number and type of crosspieces 4a-4c to be respectively installed on the body frames 1a-1c, depending on the configuration of the frameworks of roof they understand respectively.

In particular according to a first architecture of body frames 1b to be produced, their roof framework comprises a set of three crosspieces 4a-4c for receiving a fixed roof roof panel, including a front crosspiece 4a, a middle crosspiece 4b and a crosspiece rear 4c. According to a second architecture of body frames 1c to be produced, their roof framework comprises a set of two crosspieces to receive a frame for installing a glazed and / or movable roof pavilion between an open and closed position. , including a front cross member 4a and a rear cross member 4c.

The loading station comprises a single depositing station 7 for the crosspieces 4a-4c on the body frames 1a-1c to be produced which are successively presented by the routing line 2 to the loading station 3. The depositing station 7 comprises a single magazine 8 for storing the sleepers 4a-4c, on which are successively installed in packs 10 sets of three sleepers respectively before 4a, median 4b and rear 4c. The crosspieces 4a-4c are loaded adjacent to the storage magazine 8 by an operator, who has respective storage bins 9a-9c of the front crosspieces 4a, median 4b and rear 4c.

The storage magazine 8 is thus loaded in successive packets 10 of said sets of front crosspieces 4a, median 4b and rear 4c by the operator, human or automatic. The storage magazine 8 then successively routes the sets of sleeper sets 4a-4c to a single manipulator 11 fitted to the depositing station 7.

The manipulator 11 collects collectively the crosspieces 4a-4c from a package to the storage magazine 8. To this end, the manipulator 11 is equipped with a gripping head 12 which is arranged to collectively grasp the three crosspieces 4a4c of the same set of front crosspieces 4a, median 4b and rear 4c. The manipulator then deposits on the body frame 1a present at the loading station 3 at least the front crosspieces 4a and rear 4c, or even also the middle crosspiece 4b according to the architecture of the body frame 1a to be produced.

More particularly, the removal of the crosspieces 4a-4c by the manipulator 11 is carried out selectively according to the architecture of the body frame 1b-1c to be produced, under control of the control means 5. In the case where the architecture of the the body frame 1c to be produced is of the type provided with a roof frame comprising only a front crossmember 4a and a rear crossmember 4c, the manipulator 11 deposits the middle crossmember 4b in a recovery tank 13. Deposit by the manipulator 11 of the middle cross member 4b in the recovery tank 13 is preferably carried out prior to the installation of the front cross member 4a and the rear cross member 4c on the body frame 1a.

More particularly in FIGS. 2, 5 and 6, the sleepers of the same set of sleepers 4a-4c are installed on individual supports 14a-14c which equip the storage magazine 8. The supports 14a-14c are each provided with positioning members 15 for the crosspieces 4a-4c which are assigned to them and which are for example arranged in cleats and / or in pilots for positioning the crosspieces 4a-4c resting on the supports 14a-14c .

The crosspieces 4a-4c of each of the packages 10 are installed at rest on the supports 14a-14c which are assigned to them, by being positioned on the supports 14a-14c via the positioning members 15 along their main direction D1 of extension and following their transverse direction D2 which is oriented perpendicular to their main extension direction D1.

The crosspieces 4a-4c of the same package 10 are installed on the storage magazine 8 on the supports 14a-14c which are assigned to them, according to a predefined storage order. Each packet 10 of sleepers of the same set of sleepers 4a-4b is conveyed by the storage magazine 8 to the manipulator 11 in accordance with this order of storage, which is defined successively by the middle sleeper 4b, the rear sleeper 4c and the front cross member 4a.

More particularly still in FIGS. 3 and 4, and in FIGS. 7 and 8, the gripping head 12 of the manipulator 11 collectively collects the crosspieces of a set of crosspieces 4a-4c presented to the storage magazine 8 according to their storage order . Consequently, the sleepers of the same set of sleepers 4a-4c are carried by the gripping head 12 according to their order of storage on the storage magazine 8.

In addition, the crosspieces of the same set of crosspieces 4a-4c are carried by the gripping head 12 according to a predefined superposition order. According to the direction S2 for gripping the crosspieces 4a-4c by the gripping head 12, said order of superposition is defined by individual planes P1, P2, P3 for supporting the crosspieces 4a-4c by the gripping head 12.

According to said order of superposition, the rear cross member 4c is disposed at an upper plane P1 of overhang of the middle cross member 4b and of the front cross member 4a. The median cross-member 4b is arranged at a median plane P2 of overhang of the front cross-member 4a which is itself disposed at a lower plane P3.

Said storage order and / or said superposition order are defined so that any cross member 4a-4c does not prevent the installation of the other cross members 4a-4c on the body frame 1 a-1 c by the manipulator 11, regardless of the architecture of the body frame 1a-1c to be produced.

The gripping head 12 comprises a junction member 16 to the manipulator 11 which carries a beam 17, itself carrying three gripping heads 18a, 18b, 18c which are adjacent in their main direction D3 of extension. Each of the gripping heads 18a-18c is assigned to gripping a single cross member of a set of cross members 4a-4c, extending mainly in a direction D3 perpendicular to the beam 17 and parallel to the main direction D1 d 'extension of sleepers 4a-4c.

The beam 17 also forms a support for a control-command member 19 whose implementation is placed under the dependence of the control means 5. The control-command member 19 regulates the individual implementation of each of the gripping heads 18a -18c, in particular during the entry and / or the removal of the crosspieces 4a-4c by the manipulator 11 on the body frame 1b or in the recovery tank 13 as regards the middle crosspiece 4b for an architecture d 'body frame 1c free of central cross 4b.

In FIGS. 3 and 4 as well as in FIGS. 7 and 8, each of the gripping heads 18a-18c is equipped with holding members 20a-20c for the crosspiece 4a-4c which is assigned to it. Such retaining members include in particular positioning members 20a arranged for example in cleats, support members 20b configured in support fingers and / or in cleats for example, and at least one clamping member 20c, for example configured as a clamp. The holding members 20a-20c are mounted on the gripping heads 18a-18c via branches 21 which equip beams 21 a, 21 b, 21 c for mounting the gripping heads 18a-18c on the beam 17, and / or which are directly mounted on the beam 17.

The implementation of the clamping member 20c is placed under the dependence of the control-command member 19. At least one presence sensor 20d, equipping for example the clamping member 20c, makes it possible to transmit to the control unit 19 information relating to the presence or absence of a cross 4a-4c on the gripping head 18a-18c which is assigned to it.

In FIGS. 11 to 16, the gripping head 12 is approached to the body frame 1a present at the loading station 3. According to the example illustrated, the body frame 1a is intended to receive the three crosspieces 4a- 4c in accordance with its prior identification by the control means 5.

According to the embodiment of the method of the invention illustrated, a first operation of removing the front cross member 4a on the body frame 1a is carried out by the manipulator 11 as illustrated in FIG. 11 and in more detail on the Figure 12. The manipulator 11 then deposits the middle cross member 4b on the body frame 1a during a second removal operation, as illustrated in Figure 13 and in more detail in Figure 14. Then during a third operation removal, the manipulator 11 ultimately deposits the rear crossmember 4c on the body frame 1a during a third removal operation, as illustrated in FIG. 15 and in more detail in FIG. 16. The direction S3 of removal of the sleepers 4a-4c on the body frame 1a by the manipulator 11, is oriented in the direction S2 for entering the sleepers 4a-4c by the manipulator 11 at the storage store 8.

It is understood that in the case where the body frame 1c is intended to receive only a front crossmember 4a and a rear crossmember 4c for the formation of a glazed and / or movable pavilion, the second removal operation is replaced by a depositing operation of the central cross member 4b in the recovery tank 13 prior to the removal of the front cross members 4a and rear 4c on the body frame 1c.

It will also be noted more particularly in the detailed views of Figures 12, 14 and 16, that the individual removal operations of the crosspieces 4a-4c on the body frame 1a are carried out avoiding discomfort likely to be induced by the presence initial of all of the crosspieces 4a-4c of the game on the gripping head 12. Such discomfort is notably avoided due to the order of storage and / or the order of superposition of the crosspieces 4a-4c initially provided during of their collective seizure by the gripping head 12 on the storage magazine 8.

Claims (10)

1Automated process for depositing roof rails (4a-4c) on a body frame (1a-1c) at a loading station (3) participating in an assembly line and arranged along a routing line (2) step by step of box frames (1a-1c) to be produced successively, the loading station (3) comprising at least one depositing station (7) of at least one crosspiece (4a-4c) on the 'box frame (1a-1c), said at least one depositing station (7) comprising at least one store (8) for storing at least one crosspiece (4a-4c) and at least one manipulator (11) of gripping said at least one crosspiece (4a-4c) whose implementation is placed under the dependence of a control means (5) causing in a first step an entry of said at least one crosspiece (4a-4c) by the manipulator (11) and in a second step, depositing said at least one cross member (4a-4c) on the body frame (1a-1c), characterized: -) in that said first step is a step of collective entry by a single manipulator (11) of three sleepers from a set of sleepers (4a-4c) stored in a single store (8) for storage in packages (10) said set of three sleepers (4a4c), each set of sleepers (4a-4c) comprising a front cross member (4a), a middle cross member (4b) and a rear cross member (4c), and -) in that said second step is a step of successive deposition by the manipulator (11) of each of the crosspieces (4a-4c) previously entered, comprising removal operations of at least two of the three crosspieces (4a-4c) on the body frame (1a-1c), including at least the rear crossmember (4c) and the front crossmember (4a), under control of the control means (5) depending on the configuration of the body armature ( 1a-1c) to be produced previously identified. 2, - Method according to claim 1, characterized in that the second step comprises: -) successive removal operations by the manipulator (11) at least of the front crossmember (4a) and the rear crossmember (4c) on the body frame (1a-1c), and -) a depositing operation of the central crosspiece (4b) by the manipulator (11) selectively as a function of the configuration of the body frame (1a-1c) to be produced previously identified, either on the body frame (1a, 1b) being carried out between the operations for removing the front crossmember (4a) and the rear crossmember (4c), or in a recovery tank (13) being carried out before the removal operations for the rear crossmember (4c) and the front crossmember ( 4a) on the body frame (1a, 1b). 3, - Method according to any one of claims 1 and 2, characterized: -) in that it comprises an operation of loading the magazine (8) in packs (10) of said sets of sleepers (4a-4c), the sleepers (4a-4c) of each of the packs (10) being adjacent rows on the storage magazine (8) in their direction (D1) of main extension according to a sequential order of storage of the central crosspiece (4b), the rear crosspiece (4c) and the front crosspiece (4a), and - ) in that the first step is a step of collective entry of the sleepers (4a4c) by the manipulator (11) according to said order of storage. 4, - Method according to any one of claims 1 to 3, characterized in that at the end of the first step and in the direction (S2) of collective entry of the sleepers of a said set of sleepers (4a- 4c) by the manipulator (11) at the storage store (8), the crosspieces (4a-4c) are carried by the manipulator (11) according to an order of superposition according to which the rear crosspiece (4c) is arranged on a plane ( P1) upper overhang of the median cross member (4b) and of the front cross member (4a), and according to which the median cross member (4b) is arranged at a median plane (P2) of overhang of the front cross member (4a) which is arranged at a lower plane (P3). 5, - Loading station for roof rails (4a-4c) on a body frame (1a-1c) suitable for implementing a method according to any one of claims 1 to 4, characterized in that '' it includes a so-called deposit station (7) which is unique and which includes: -) a single said store (8) for storing packets (10) of sets of crosspieces (4a4c) each comprising three crosspieces including a rear crosspiece (4c), a middle crosspiece (4b) and a front crosspiece (4a), and -) a single manipulator (11) for collective entry of the crosspieces of a said set of crosspieces (4a-4c) and of successive individual deposits of the crosspieces (4a-4c) at said single deposition station (7). 6, - Loading station according to claim 5, characterized in that for each of the packages (10) of said sets of sleepers (4a-4c), the storage magazine (8) comprises supports (14a-14c) individual sleepers (4a-4c) in respective predefined positions relative to each other, said supports (14a-14c) being each provided with at least positioning members (15) of the sleepers (4a-4c) assigned to them. 7, - Loading station according to any one of claims 5 and 6, characterized in that the manipulator (11) is equipped with a gripping head (12) collective of the sleepers of a said set of sleepers (4a- 4c), the gripping head (12) comprising individual gripping heads (18a-18c) of the crosspieces (4a-4c) in respective predefined positions relative to each other in correlation with the respective positions at least adjacent to the sleepers (4a4c) in the storage magazine (8). 8, - Loading station according to claim 7, characterized in that the gripping head (12) is provided with a junction member (16) to the manipulator (11) in an assembly direction between them and a support beam (17) adjacent to the gripping heads (18a-18c) which is oriented perpendicular to said assembly direction and perpendicular to a main direction (D2) of extension of the gripping heads (18a-18c) oriented along the main extension direction (D1) of the crosspieces (4a-4c) assigned to them. 9, - Loading station according to claim 8, characterized in that said beam (17) forms a support for a control-command member (19) for the individual implementation of each of the gripping heads (18a-18c ), the implementation of which is placed under the dependence of the control means (5). 10, - Loading station according to any one of Claims 7 to 9, characterized in that each of the gripping heads (18a-18c) is equipped with at least one positioning member (20a) on the gripping head ( 18a-18c) of the crosspiece (4a-4c) which is assigned to it, of at least one clamping member (20c) of said crosspiece (4a-4c) which is assigned to it, of at least one member of support (20b) of said crosspiece (4a-4c) which is assigned to it against the gripping head (18a-18c), and of at least one presence sensor (20d) on the gripping head (18a-18c) of said crosspiece (4a4c) which is assigned to it.