WO2008155478A1

WO2008155478A1 - Linear displacement module provided by numerous linearly displaceable end stops, motor vehicle assembly line tool provided with such a module and use of this tool

Info

Publication number: WO2008155478A1
Application number: PCT/FR2007/051485
Authority: WO
Inventors: Philippe Rocton
Original assignee: Renault S.A.S
Priority date: 2007-06-21
Filing date: 2007-06-21
Publication date: 2008-12-24

Abstract

The invention relates to a linear displacement module (40) comprising a chassis (41), a carriage (43) mounted on the chassis so that it can be linearly displaced with respect to the chassis and a carriage displacement actuator (44), the carriage being able to move between an initial rest position in which it butts against one end of the chassis and a plurality of stopped positions of use, characterized in that it comprises an end stops support mounted on the chassis and linearly displaceable relative thereto, said support bearing a number of end stops (46) each corresponding to one position of use of the carriage, the support being mounted in such a way that the carriage can interact with one end stop at a time through linear displacement of the end stops support. The invention also relates to a corresponding motor vehicle assembly line tool and to the use thereof.

Description

LINEAR DISPLACEMENT MODULE WITH MULTIPLE

LINEARLY DISPLACEABLE ARROW TOPS, TOOL OF A

ASSEMBLY LINE FOR A MOTOR VEHICLE WITH A

SUCH MODULE AND USE OF THIS TOOL. The invention relates to a linear displacement module provided with multiple linearly movable stops, a tool of a motor vehicle assembly line provided with such a module and the use of this tool, in particular for the implementation of geometric conformation of a sheet metal part on a motor vehicle assembly line.

A motor vehicle assembly line requires the use of movable supports for the movement of tools, in particular for moving the positioning tools of the sheet metal parts to be assembled, also known as geometric configuration tools.

These mobile supports must be able to ensure a great diversity of positioning in a fixed reference (X, Y, Z) with respect to the assembly station, in order to allow their use for the assembly of vehicles of different ranges or models, thus ensuring a flexibility in the assembly.

Such a diversity of positions can currently be obtained by means of supports that can be moved linearly along the three axes of the fixed reference frame by means of numerical controls. An infinity of stop positions can then be obtained for each of the displacement axes. Such supports are however very expensive, especially since it is generally not necessary to have an infinity of stop positions, only fifteen to twenty stop positions for each axis can be sufficient to obtain a acceptable flexibility of the mobile support. Another less expensive solution is to use movable electrically controlled or pneumatic, working between two stops. However, such supports provide a very small number of stop positions for each axis (two stop positions per axis), which does not allow sufficient flexibility of the assembly line.

There is therefore currently no mobile support to obtain a number of stop positions along an axis sufficient to to ensure a certain flexibility of the assembly line (for example between 4 and 8), in a simple way and for a reasonable cost.

The invention aims to overcome these drawbacks by proposing a linear displacement module making it possible to ensure a large number of positions in a simple manner, and at a lower cost, while ensuring the level of precision of the stop positions given by a solution of stop on stop, compatible with the requirements for assembly lines.

For this purpose, a first object of the invention relates to a linear displacement module comprising a frame, a carriage mounted on the frame so as to be linearly movable relative to the frame and a cylinder for moving the carriage, the carriage being movable. between an initial position of rest in which it is in abutment against one end of the frame, and a plurality of stop positions of use, characterized in that it comprises a support stops mounted on the frame movable linearly relative to it, said support carrying a plurality of stops each corresponding to a position of use of the carriage, the support being mounted so that the carriage can engage with a stop at a time by linear displacement of the abutment support.

The module according to the invention has the following advantages:

- Possibility of ensuring a number of stopping positions of the carriage greater than 4: it is sufficient to adapt the dimensions of the abutment support; - reduced size of the support stops;

- simplicity of realization and development;

- ease of use and maintenance.

Advantageously, each stop is removable and / or movable.

The stop positions of the carriage of the linear module according to the invention can thus easily be adapted to each new range or new model of a motor vehicle, and this for a very low cost.

In a particular embodiment, each stop is formed by the end face of a bar fixed on the support parallel to the direction of movement of the carriage.

Each stop position of the carriage thus corresponds to a stop of a specific length. Advantageously, the module is equipped with a means for driving the abutment support.

According to one embodiment, this drive means can be actuated by a control device. According to different variants, the drive means may be an electric motor, a pneumatic cylinder or more simply and cheaply a cable.

According to one embodiment, the module may also be equipped with means for detecting the position of the abutment support. The invention also relates to a tool of a motor vehicle assembly line comprising a mobile support provided with at least one linear displacement module according to the invention.

According to one embodiment, it is possible to produce a tool whose movable support comprises three linear displacement modules according to the invention for a displacement along each of the three axes of a given reference frame.

Of course, it is also possible to combine a linear displacement module according to the invention with a rotation device.

The invention also relates to the use of a tool according to the invention for the geometric conformation of a sheet metal part on a motor vehicle assembly line.

The linear displacement module according to the invention makes it possible to achieve the necessary positioning accuracy for a tool of this type. The invention is now described with reference to the accompanying non-limiting drawings, in which: FIG. 1 is a perspective representation of a tool equipped with three linear displacement modules according to the invention; - Figure 2 is a perspective representation of the interior of the tool shown in Figure 1; FIG. 3 is an enlarged view of the interior of one of the modules of FIG. 2.

FIG. 1 represents a tool 10 of a motor vehicle assembly line comprising a mobile support provided with three linear displacement modules 20, 30, 40 according to the invention, intended to respectively to the movement of the tool along the X, Y, Z axes of a fixed reference.

More specifically, it is a tool for geometric conformation of a sheet metal part on a motor vehicle assembly line. For this purpose it supports at least one clamping element 11 for holding the sheet metal part (not shown).

Each linear displacement module 20, 30, 40 comprises a frame 21, 31, 41 equipped with rails 22, 32, 42, a carriage 23, 33, 43 slidably mounted on the rails and a cylinder 24, 34, 44 for moving the carriage.

In the example, the carriages 23 and 33 slide by means of pads on two rails 22, 32 of the frames 21, 31 respectively. These carriages are in the form of plates. The slide carriage 43 along the Z axis has a generally parallelepiped shape supporting the clamping element 11. This carriage 43 slides relative to the frame 41 by means of four rails 42, located at each corner of the frame. Of course, one could provide a carriage sliding on two rails in this direction.

Each carriage 23, 33, 43 is movably mounted between an initial rest position in which it abuts against one end of the frame, and a plurality of positions of use stops.

According to the invention, each frame 21, 31, 41 comprises an abutment support 25, 35, 45 mounted on the frame movable linearly with respect thereto. This support 25, 35, 45 carries a plurality of abutments 26, 36, 46 each corresponding to a position of use of the carriage, the support being mounted so that the carriage can come into engagement with a stop at a time by linear displacement. support stops.

For this purpose, each carriage is equipped with an element 421 engaging a stop 46, as visible only for the module 40 in FIG.

For trolleys 21 and 31, this element is fixed on the underside of the carriage, and enters the chassis through a slot 12 (shown only in Figure 1). In the example shown, each abutment 26, 36, 46 is formed of a longitudinal bar of square section, one end of which is pressed against the support of abutments, and the other end of which is free, the face of the latter forming a stop to block the movement of the carriage. Each bar is fixed parallel to the direction of movement of the corresponding carriage. The stop support moves in turn in a direction perpendicular to the displacement of the carriage so as to be able to place each stop in front of a corresponding stop of the carriage.

Thus, at each stop position of a carriage, there is a stop 26, 36, 46 having a specific length.

The displacement of the stops is described in more detail with reference to FIG. 3. This displacement is identical for each of the modules.

Each stop 46 is mounted on a movable plate 45a of the support, this plate being slidably mounted in a part 45b integral with the frame of the linear module, in a direction perpendicular to the direction of travel of the carriage. The linear displacement of the movable plate 45a ensures the displacement of the stops, and the change of the stop position of the corresponding carriage.

Such an arrangement ensures identical positioning accuracy of each abutment with respect to the abutment support, provided that the length of the abutment has been measured with sufficient precision. The assembly can thus be carried out very quickly since it is not necessary to adjust the position of each stop.

The adjustment of the removable stop position, in the axis of the linear movement, can be achieved by wedging relative to the removable stops support.

Of course, other forms of abutments can be envisaged, provided that the stop can block the linear displacement of the carriage to maintain it in a specific stop position.

Each stop is removably attached to the abutment support, and more specifically to the movable plate thereof, which allows easy replacement of a stop in case of wear or when it is necessary to provide a new position. stopping a trolley.

In the example, each stop is fixed on the abutment support by means of a screw 47. For this purpose, the abutment has a generally L-shaped shape, the base of the L resting on the movable plate 45a and being screwed to the latter (see Figure 3), the free end forming the surface against which the carriage abuts. Each stop support is also equipped with a drive means.

It may be an electric motor, in particular an electric geared motor, or a pneumatic cylinder. In the example shown, the drive means is formed of a cable 28, 38, 48, one end of which is integral in translation with the abutment support and the other end is connected to a control lever 13. This last command the displacement of the cables by means of a rack-and-pinion transmission 14. The different positions of rotation of the abutment support can then be identified at the level of the control lever 13 in order to position the tool in a specific position. This solution has the advantage of being particularly simple and inexpensive to implement.

It is also possible to provide a means for detecting the position of the abutment support coupled to these means for controlling the driving of the abutment support.

Claims

A linear displacement module (20, 30, 40) having a frame (21, 31, 41), a carriage (23, 33, 43) mounted on the frame so as to be linearly movable relative to the frame and a carriage displacement cylinder (24, 34, 44), the carriage being movable between an initial position of rest in which it is in abutment against one end of the frame, and a plurality of stop positions of use, characterized in that it comprises a stop support mounted on the frame movable linearly relative thereto, said support carrying a plurality of stops (26, 36, 46) each corresponding to a position of use of the carriage, the support being mounted so that the carriage can engage with one stopper at a time by linear displacement of the abutment support.

2. linear displacement module according to claim 1, characterized in that each stop is removable and / or movable.

3. Linear displacement module according to one of claims 1 or 2, characterized in that each stop is formed by the end face of a bar fixed on the support parallel to the direction of movement of the carriage.

4. Linear displacement module according to one of claims 1 to 3, characterized in that it is equipped with a drive means of the abutment support.

5. linear displacement module according to claim 4, characterized in that the drive means is an electric motor.

6. linear displacement module according to claim 4, characterized in that the drive means is a pneumatic cylinder.

7. Linear displacement module according to claim 4, characterized in that the drive means is a cable.

8. Linear displacement module according to one of claims 1 to 7, characterized in that it is equipped with means for detecting the position of the abutment support.

9. Tool of a motor vehicle assembly line comprising a mobile support provided with at least one linear displacement module according to one of claims 1 to 8.

10. Use of a tool according to claim 9 for the geometric conformation of a sheet metal part on a motor vehicle assembly line.