ASSEMBLY SYSTEM COMPRISING A TOOL FOR CLAMPING A PART TO A SUPPORT IN AN ASSEMBLY

Abstract

An assembly system comprising a set having in a recess (2) at least one part (4) to be clamped onto a support (6) by a screw (8) engaged in a forward axial direction (AV), and comprising a tool (12) for positioning the screw (8) including a rear face for positioning (16) on a reference surface (18) of the assembly, and a forward-facing through channel (20) for axially guiding the screw (8) and a clamping sleeve for this screw (24), this channel (20) terminating after positioning with a front face (22) disposed near the part to be clamped (4). Figure 1

Description

Title of the invention: ASSEMBLY SYSTEM COMPRISING A TOOL FOR CLAMPING A PART TO A SUPPORT IN AN ASSEMBLY

[0001] The present invention relates to an assembly system comprising an assembly, a part to be clamped on a support in a hollow of this assembly with a screw engaged in an axial direction, and a tool for setting up the screw, as well as a method for assembling such an assembly with this tool.

[0002] A type of tooling known, presented in particular by document FR-A1-2951130, allowing the clamping of a sub-assembly on an external surface of an assembly, which is difficult to access, with fixing screws engaged in holes in this sub-assembly, then screwed into holes in the surface, includes a guide plate fixed to the rear of this sub-assembly.

[0003] The guide plate has, in alignment with each fixing screw inserted into its bore in the sub-assembly, a housing receiving a drive sleeve for rotating the screw.

[0004] After positioning a front face of the sub-assembly on the surface of the assembly, the sockets housed in the holes of the guide plate fixed at the rear are already in position to receive a screwdriver which drives them by tightening the screws.

[0005] This avoids the delicate positioning of the screws and then the sockets on a sub-assembly located in a hard-to-reach place, particularly in the engine compartment of a motor vehicle which generally has little free space to maneuver.

[0006] However, this tooling is intended to be fixed to the rear of a sub-assembly, with the screws already installed which are aligned and held in position in the holes of this sub-assembly.

[0007] In some cases, it is necessary to fix a thin part, which may be quite thin, to a support with a threaded hole, using at least one screw, in a space that is difficult for an operator to access. Because the thinness of the part makes it impossible to guide and hold the screw before tightening, the operator must hold it in position while simultaneously guiding the clamping sleeve to reach the screw, which in some cases is difficult or impossible due to lack of space.

[0008] In particular, within the recess of an assembly, such as a motor vehicle gearbox, a flat lug of an electrical wire can be fixed to a support having a threaded hole to ensure an electrical connection, by means of a screw engaged in a hole in this lug.

[0009] In this case, problems arise, particularly in a hollow making it difficult for the operator to manually prepare the screw in position in alignment with the holes, hold it inserted in the hole in the thin part, with the clamping sleeve positioned on the screw head, and then rotate it to engage the first turns of its thread.

[0010] It should be noted that the thinness of the part to be fixed to the support does not allow the screw engaged in the drilling of this part to be held in position and aligned while waiting to be tightened.

[0011] The present invention is specifically intended to avoid these problems of the prior art.

[0012] To this end, it proposes an assembly system comprising a set having in a hollow at least one part to be clamped on a support with a screw engaged in a forward axial direction, and comprising a tool for setting up the screw, this system being remarkable in that the tool has a rear face for positioning on a reference surface of the assembly, and a conduit turned towards the front for axial guidance of the screw and a clamping sleeve for this screw, this conduit ending after positioning with a front face arranged near the part to be clamped.

[0013] One advantage of this assembly system is that the conduit, positioned precisely on the assembly thanks to its rear positioning face, allows, in a hollow which may be difficult to access, the screw with its socket to be placed as close as possible to the part to be tightened on the support while ensuring axial alignment with the holes.

[0014] Then, from a rear entry of the tool conduit, the screw can easily be tightened, remaining aligned, and presenting its front end positioned as close as possible to the drilling of the part thanks to the front face of its conduit coming close.

[0015] The assembly system according to the invention may further comprise one or more of the following features, which may be combined with each other.

[0016] Advantageously, the positioning face of the tooling constitutes a plane arranged along a transverse direction.

[0017] In this case, advantageously the tooling comprises a rear part forming a band, presenting the positioning face which is turned towards the front direction.

[0018] Advantageously, the tooling comprises several conduits, each receiving a screw for clamping a part onto a particular support.

[0019] In this case, the conduits may have axes arranged in the same plane.

[0020] In particular, the conduits may have front faces arranged in transverse planes that are different.

[0021] In particular, the assembly can constitute a motor vehicle gearbox.

[0022] In this case, each part to be clamped can constitute a lug fixed to the end of a wire electrical, which is assembled on a support constituting a connector.

[0023] The invention also relates to a method of assembling a set of a system comprising any one of the preceding characteristics, remarkable in that it includes a step of placing the tooling on the set by its positioning face, a step of inserting a screw into each channel, then a step of tightening each screw by a clamping sleeve which is guided in the screw channel.

[0024] The invention will be better understood and other features and advantages will become more apparent upon reading the following description given by way of example, with reference to the accompanying drawings in which:

[0025] [Fig-1] is a side view of a tooling of an assembly system according to the invention, shown partially in axial section;

[0026] [Fig.2] is a rear view of this tool positioned on an assembly forming a motor vehicle gearbox; and

[0027] [Fig.3] is a side view of this tool arranged in the gearbox.

[0028] Figures 1 and 2 show a recess 2 formed in the casing of a gearbox, comprising six metallic conductors, each forming an independent support 6, which receives a lug 4 forming a fixed part at the end of an electrical wire to ensure a connection. Each lug 4 has a hole receiving, along an axial direction AV, a screw 8 which is tightened into a threaded hole in the support 6.

[0029] The supports 6, having axes aligned in the same plane, are all offset from each other along the axial direction.

[0030] It should be noted that the lugs 4 have a reduced thickness, and their holes cannot achieve axial alignment of a screw 8 engaged in them. The hollow of the housing 2 leaves little room for an operator's fingers to engage in order to hold each screw 8 in axial position.

[0031] Positioning and holding the screws 8 without specific tools, and engaging a rear clamping bit 24, is a delicate and time-consuming operation, and carries a risk of damaging the thread of the support 6 if screwing begins when the screw alignment is not correct.

[0032] Manually positioning the screws 8 without guidance can also lead to the screw falling into the hollow of the gearbox casing 2 in the event of incorrect operation, which then wastes time to retrieve it.

[0033] In addition, this screw positioning operation 8 must be repeated six times to fix each lug 4 onto its support 6.

[0034] A positioning tool 12 formed from a block in a plastic material, includes a rear part 14 forming an elongated band along the transverse direction, having rounded ends.

[0035] The rear part 14 has a transverse front face 16 comprising a contour which bears against a machined face 18 formed in a recess in the gearbox housing. In a first operation, the tool 12 is placed on the housing, which, thanks to the support on the machined face 18, provides precise positioning of this tool.

[0036] The front face 16 of the tooling 12 has six parallel conduits through 20, opening out on both sides, of circular section, each aligned on the axis of a screw 8, each transverse front face 22 of conduit 20 being fitted on the rear face of the corresponding lug 4.

[0037] Each conduit 20 receives in a fitted manner a screw 8 with its head 10, engaged in it, as well as a clamping sleeve 24 having a front form which fits into the housing of this screw head, and a rear form which receives the front end of a screwdriver to transmit the torque of the screwdriver to the screw.

[0038] In a screw preparation operation 8, these screws can be engaged beforehand in the conduits 20 before the positioning of the tooling 12 on the gearbox housing, or after this positioning.

[0039] For each screw 8, a precise alignment is obtained with respect to the holes in the lug 4 and the support 6 corresponding to this screw, as well as a positioning just in front of these elements thanks to the transverse front face 22 of its conduit 20 which comes to rest on the lug.

[0040] In a subsequent operation, a clamping sleeve 24, disposed at the end of a screwdriver, is engaged behind each screw 8 with sufficient fit in the channel 20 to provide guidance for the sleeve, driving it directly onto the rear shape of the screw head 10 to ensure its engagement. The screwdriver is then activated to perform torque tightening.

[0041] Alternatively, a multi-spindle screwdriver can be used, driving several sockets 24 to ensure the tightening of several screws 8 or all the screws at the same time.

[0042] After the removal of the tooling 12, a closing plate for the rear entrance of the hollow 2, not shown, is screwed onto the outer face 28 of this hollow with screws engaged in holes 26 surrounding this entrance.

[0043] Fig. 3 shows a flywheel fixed on an input shaft of the gearbox 30, arranged in a plane parallel to the plane of the conduits 20, which has an opening 32 giving lateral access to the lugs 4 and the supports 6. The supports 6 arranged near the axis of the input shaft are at the edge of the opening 32 with difficult manual access through this opening.

[0044] In this case, the tool 12 introduced on the side of the gearbox allows the screws 8 to be positioned and tightened without having to intervene by opening the flywheel 32.

[0045] A simple and quick assembly of the screws 8 is obtained without modifying the assembly comprising the gearbox housing, the lugs 4 and the supports 6, with the use of the appropriately made tooling 12, comprising a number of conduits 20, a positioning of their axes and their transverse front faces 22 which are adapted, which avoids losing them or damaging the threads.

Claims

Demands

1. Assembly system comprising an assembly having in a hollow (2) at least one part (4) to be clamped on a support (6) with a screw (8) engaged in a forward axial direction (AV), and comprising a tool (12) for setting up the screw (8), characterized in that the tool (12) has a rear face for positioning (16) on a reference surface (18) of the assembly, and a forward-facing through channel (20) for axially guiding the screw (8) and a clamping sleeve for this screw (24), this channel (20) ending after positioning with a front face (22) disposed near the part to be clamped (4).

2. Assembly system according to claim 1, characterized in that the positioning face (16) of the tooling (12) constitutes a plane arranged along a transverse direction.

3. Assembly system according to claim 2, characterized in that the tooling (12) comprises a rear part (14) forming a band, having the positioning face (16) which is turned towards the front direction.

4. Assembly system according to any one of the preceding claims, characterized in that the tooling (12) comprises several conduits (20) each receiving a screw (8) for clamping a part (4) onto a particular support (6).

5. Assembly system according to claim 4, characterized in that the conduits (20) have axes arranged in the same plane.

6. Assembly system according to claim 4 or 5, characterized in that the conduits (20) have front faces (22) arranged in different transverse planes.

7. Assembly system according to any one of the preceding claims, characterized in that the assembly constitutes a motor vehicle gearbox.

8. Assembly system according to claim 7, characterized in that each clamping part (4) constitutes a lug fixed to the end of an electrical wire, which is assembled on a support (6) constituting a connector.

9. Method of assembling a system assembly according to any one of the preceding claims, characterized in that it comprises a step of placing the tooling (12) on the assembly by its positioning face (16), a step of inserting a screw (8) in each conduit (20), then a tightening step of each screw (8) by a clamping sleeve (24) which is guided in the screw conduit (20).

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