ASSEMBLY SYSTEM COMPRISING A TOOL FOR CLAMPING A PART TO A SUPPORT WITHIN 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 TOOLING FOR A SCREW FOR TIGHTENING A PART ON 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 positioning the screw, as well as a method of assembling such an assembly with this tool.

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

[0003] The guide plate comprises, in alignment with each fixing screw inserted into its drilling of the subassembly, a housing receiving a sleeve for driving the screw in rotation.

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

[0005] This avoids the need for difficult positioning of screws and then sockets on a subassembly located in a location that is difficult to access, particularly in the engine compartment of a motor vehicle which generally has little free space for maneuvering.

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

[0007] In certain cases it is necessary to fix with at least one screw, in a space that is difficult for an operator to access, a part that may have a small thickness on a support comprising a threaded hole. The small thickness of the part does not allow the screw to be guided and held before tightening, the operator must then hold it in position at the same time as guiding the clamping sleeve to reach this screw, which in certain cases is difficult or impossible due to lack of space.

[0008] In particular, it is possible, in the hollow of an assembly, a gearbox of a motor vehicle for example, to fix a flat terminal of an electric wire on a support comprising a threaded hole to ensure an electrical connection, by a screw engaged in a hole in this terminal.

[0009] In this case, problems arise, particularly in a hollow making manual operation by the operator difficult, to successively 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, then rotate it in order to engage the first turns of its thread.

[0010] It will be noted that the small thickness of the part to be fixed on the support does not allow the screw engaged in the drilling of this part to be held in position and its alignment while waiting for it to be tightened.

[0011] The present invention aims in particular to avoid these problems of the prior art.

[0012] To this end, it proposes an assembly system comprising an assembly 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 positioning the screw, this system being remarkable in that the tool comprises a rear face for positioning on a reference surface of the assembly, and a conduit facing forward for axial guidance of the screw and a clamping sleeve for this screw, this conduit ending after positioning by a front face arranged near the part to be clamped.

[0013] An 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, to position the screw with its socket 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, it is easy to tighten the screw which remains aligned, and has its front end arranged as close as possible to the drilling of the part thanks to the front face of its conduit coming nearby.

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

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

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

[0018] Advantageously, the tooling comprises several conduits each receiving a screw for tightening a part on 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 which are different.

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

[0022] In this case, each part to be tightened can constitute a terminal 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 for assembling an assembly of a system comprising any one of the preceding characteristics, remarkable in that it comprises a step of placing the tooling on the assembly by its positioning face, a step of inserting a screw into each conduit, then a step of tightening each screw by a tightening sleeve which is guided in the conduit of the screw.

[0024] The invention will be better understood and other characteristics and advantages will appear more clearly on reading the description below given by way of example, with reference to the appended drawings in which:

[0025] [Fig-1] is a side view of a tool of an assembly system according to the invention, presented 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 hollow 2 formed in the casing of a gearbox, having six metal conductors each forming an independent support 6 receiving a terminal 4 forming a part fixed to the end of an electric wire to ensure a connection. Each terminal 4 has a hole receiving in an axial direction before AV a screw 8 which is tightened in a threaded hole of the support 6.

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

[0030] It will be noted that since the lugs 4 have a reduced thickness, their drillings cannot achieve axial alignment of a screw 8 engaged therein. The hollow of the casing 2 leaves little room to engage the fingers of an operator in order to maintain each screw 8 in axial position.

[0031] Positioning and holding the screws 8 without specific tools, and engaging a rear clamping end piece 24, constitutes a delicate operation, taking time, and involves a risk of damaging the thread of the support 6 in the case where screwing begins when the alignment of the screw is not good.

[0032] Positioning the screws 8 manually, without guidance, can also cause the screw to fall into the hollow of the gearbox casing 2 in the event of a false maneuver, which then causes time to be lost in retrieving it.

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

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

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

[0036] The front face 16 of the tool 12 comprises six parallel conduits passing 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 adjusted on the rear face of the corresponding terminal 4.

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

[0038] In an operation of preparing the screws 8, these screws can be engaged beforehand in the conduits 20 before positioning the tool 12 on the gearbox casing, or after this positioning.

[0039] For each screw 8, a precise alignment is obtained with respect to the holes in the terminal 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 bear on the terminal.

[0040] In a following operation a clamping sleeve 24, arranged at the end of a screwdriver, is engaged behind each screw 8 with a sufficient fit in the conduit 20 to obtain guidance of the sleeve leading it directly onto the rear shape of the screw head 10 in order to ensure its drive. The screwdriver is then activated to carry out tightening to the torque.

[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 removing the tool 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 to 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 makes it possible to position and tighten the screws 8 without having to intervene by opening the flywheel 32.

[0045] A simple and rapid assembly of the screws 8 is obtained without modifying the assembly comprising the gearbox casing, the terminals 4 and the supports 6, with the use of the tooling 12 produced in an appropriate manner, comprising a number of conduits 20, a positioning of their axes and their front transverse faces 22 which are adapted, which avoids losing them or damaging the threads.

Claims

Claims

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

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

3. Assembly system according to claim 2, characterized in that the tool (12) comprises a rear part (14) forming a strip, 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 tool (12) comprises several conduits (20) each receiving a screw (8) for tightening a part (4) on 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 transverse planes which are different.

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 part to be tightened (4) constitutes a terminal fixed to the end of an electric wire, which is assembled on a support (6) constituting a connector.

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

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