FR3063393A1 - DEVICE FOR MOUNTING ELECTRIC TERMINALS. - Google Patents

Abstract

The invention relates to a grounding device comprising a metal stud (20) having a first threaded rod (21) and a collar (22) extending radially at the base of this rod (21), the stud (20) being intended to be fixed against a metal wall (4) so that the collar (22) is pressed against a first face (4B) of the wall (4), the first rod (21) being intended for cooperate with a first nut (5) to allow the attachment of at least one lug (40) threaded on this first rod (21), the stud having a second threaded rod (23) aligned coaxially with the first rod (21) and extending to the opposite of the latter from the collar (22), this second rod (23) being engaged through an orifice (6) formed in the wall (4), then screwed into a second nut (7). ) welded on the periphery of the orifice (6) against the second face (4A) of the wall (4), the collar (22) having a polygonal outer section intended to ensure the screwing of the second rod (23) on the second nut (7).

Description

Holder (s): PEUGEOT CITROEN AUTOMOBILES SA Société anonyme.

Extension request (s)

Agent (s): PEUGEOT CITROEN AUTOMOBILES SA Public limited company.

DEVICE FOR EARTHING ELECTRIC TERMINALS.

FR 3,063,393 - A1 (5f) The invention relates to a grounding device comprising a metal stud (20) provided with a first threaded rod (21) and a collar (22) extending radially to the base of this rod (21), the stud (20) being intended to be fixed against a metal wall (4) so that the collar (22) is pressed against a first face (4B) of the wall (4), the first rod (21) being intended to cooperate with a first nut (5) to allow the fixing of at least one terminal (40) threaded on this first rod (21), the stud comprising a second threaded rod (23) aligned coaxially with the first rod (21) and extending opposite the latter from the collar (22), this second rod (23) being engaged through an orifice (6) formed in the wall (4) , then screwed into a second nut (7) welded on the periphery of the orifice (6) against the second face (4A) of the wall (4), the collar (22) having a s polygonal external ection intended to ensure the screwing of the second rod (23) on the second nut (7).

DEVICE FOR EARTHING ELECTRIC TERMINALS.

Field of the invention

The invention relates to the field of grounding electrical lugs for harnesses and / or electrical cables connected to electrical devices.

Invention background

In a motor vehicle, electrical devices such as starters, alternators or computers must be grounded to the body via an electrical conductor consisting of a harness or an electrical cable connected by its first end to said electrical device and on the second end of which is crimped a ground connection lug made of a relatively soft metallic material and having good electrical conductivity.

As the hardness of these ground connection lugs is not high enough to withstand the tightening torques applied at the points of attachment of these electrical devices to the chassis (significant risk of the terminal creeping), it is therefore necessary to provide specific ground connections conventionally constituted by a stud or a metallic nut welded on the internal face of one of the sheets of the front part of the body delimiting the engine compartment.

These earth connections are intended to cooperate with a screw (respectively, a nut when the earth connection is a stud) in order to allow fixing between the nut and the screw head (respectively, between the collar and the nut) at least one lug threaded beforehand on the rod of the screw (respectively, on the rod of the stud) and thus ensuring the earthing of the corresponding device or devices.

In order to limit the number of these earth connections, it is common to fix several lugs coming from different electrical devices on the same earth point.

To facilitate the attachment of several terminals, it is known in particular from French patent applications FR 2 693 842 and FR

990 066, to provide a distribution cup allowing the reception of a plurality of lugs crimped at the ends of harnesses and / or electric cables, the latter being stacked and oriented differently in order to allow a saving of space, while guaranteeing the anti-rotation of each of the harnesses and / or cables.

Such a cup comprises a circular base surmounted by a plurality of peripheral slots angularly spaced and delimiting between them passage windows each intended to be crossed radially by the crimping end of a terminal.

The base is provided with an indexing hole whose profile is complementary to that of the external section of the nut constituting the ground connection (or, when the latter is formed by a stud, of the internal section of a collar extending radially at the base of this stud), so that it can fit together by shape correspondence.

The mounting of such a cup is carried out by previously fitting its base on the nut (respectively, on the collar when the ground connection is a stud), then by stacking the lugs on this base so that their end pieces project radially each from a different window, and finally by screwing a screw passing through the lugs on this nut (respectively, a nut on the threaded rod of the stud passing through the lugs) to allow fixing between the screw head and this base (respectively, between the nut and this base) of at least one said electrical terminal threaded beforehand on the rod of the screw (respectively, on the rod of the stud).

Once in place, cooperation by interlocking shapes between the cup and the ground connection prevents any relative rotation between these two elements, the lugs also being locked in rotation relative to the cup thanks to the presence of the slots.

The ever increasing increase in the number of electrical devices in the engine compartment of vehicles however leads to an increasingly drastic reduction in the space available, which makes it increasingly difficult or impossible to introduce the welding heads. necessary for the installation of ground connections on the internal faces of the sheets delimiting this compartment.

Subject and summary of the invention

The present invention therefore aims to facilitate the earthing of the electrical terminals present in the engine compartment of a motor vehicle.

To this end, it proposes a device for grounding electrical terminals comprising a metal grounding stud provided with a first threaded rod and a collar extending radially at the base of said first rod, said stud being intended to be fixed against a metal wall so that said collar is pressed against a first face of said wall, said first threaded rod being intended to cooperate with a first nut to allow fixing between said collar and this nut at least an electric terminal threaded beforehand on this first rod;

characterized in that said stud further comprises a second threaded rod aligned coaxially with said first rod and extending opposite to the latter from said collar, said second rod being intended to be engaged through an orifice provided in said wall, then screwed into the thread of a second nut welded on the periphery of said orifice against the second face of said wall, said collar further having a polygonal outer section intended to cooperate with a screwdriver of complementary shape to ensure screwing said second threaded rod onto said second nut.

Due to the particular conformation of this stud, its installation does not require any welding to be carried out on the face of the wall oriented on the side where the lug (s) are (the second nut ensuring the fixing of this stud being welded on the opposite side).

Such a stud can thus be installed on a sheet metal partially delimiting a congested compartment housing one or more lugs to be grounded (such as the engine block of a motor vehicle) where the lack of space does not allow the introduction of a welding head.

According to preferred characteristics of the device according to the invention, taken alone or in combination:

- Said collar has an octagonal external section;

- The thread of said second rod of said stud is of the self-tapping type;

- Said second rod has a length greater than the thickness of said second nut so as to be able to serve, after the positioning of said stud, as a fixing point for another member of the vehicle;

- Said device further comprises a distribution cup comprising a base surmounted by a plurality of peripheral slots delimiting between them passage windows each intended to be crossed radially by a part of a said terminal, said base being provided with a hole indexing whose profile is complementary to that of the polygonal outer section of said collar, so as to be able to fit there by shape correspondence;

- Said distribution cup came in one piece by molding from a thermoplastic material;

- Said distribution cup comprises means for axially retaining the at least said terminal;

- Said axial retaining means consist of elastically deformable tongues extending at the top of said peripheral slots and each projecting tangentially on either side of a said slot, the spacing between the free ends facing the tongues of two adjacent peripheral slots being less than the width of said part of a said terminal;

- Said dispensing cup includes anti-retraction means capable of cooperating by snap-fastening during its fitting with complementary means provided on said collar of the grounding stud to prevent its accidental dislocation; and or

- Said anti-shrinkage means comprises two elastic tabs of smaller thickness than said base and projecting radially, diametrically opposite, inside said indexing hole from the face of said base turned towards said wall, said tabs being intended to snap into an annular clearance formed on said collar of the stud.

Brief description of the drawings

The description of the invention will now be continued with the detailed description of an exemplary embodiment, given below by way of illustration but not limitation, with reference to the appended drawings, in which:

- Figure 1 is a partial perspective view of the side portion of the front block of the body of a motor vehicle on which is installed a device for grounding electrical terminals according to the invention;

- Figure 2 shows a perspective view of the double stud of the earthing device of Figure 1;

- Figure 3 is a perspective view of the distribution cup of the earthing device of Figure 1; and

- Figure 4 shows a sectional view of the earthing device in its configuration of Figure 1.

Detailed description of an embodiment

FIG. 1 represents a partial perspective view of the front unit of the body of a motor vehicle delimiting its engine compartment and comprising in particular an apron cross member 2 as well as a lateral passage of the front wheel 3 obtained by stamping a sheet metal steel 4.

As illustrated in this figure, this sheet 4 accommodates a grounding device 10 designed to receive a plurality of metallic electrical lugs 40 each comprising a circular support plate 41 in which an equally circular insertion opening 42 is formed, as well as a crimping end piece 43 fixed to one end of a bundle or of an electric cable 44 connected to an electrical appliance not shown of this vehicle.

The earthing device 10 consists of a metal earthing stud 20 and a distribution cup 30.

The grounding stud 20, illustrated alone in FIG. 2, conventionally comprises a first threaded cylindrical rod 21 and a collar 22 forming a shoulder extending radially at the base of this rod 21.

The first threaded rod 21 is intended to cooperate with a first nut 5 (see FIG. 4) to allow the fixing between the collar 22 and this nut 7 of one or more lugs 40 threaded beforehand on this rod 21, so as to ensure the earthing of the corresponding electrical appliance (s).

According to the invention, the grounding stud 20 further comprises a second threaded cylindrical rod 23 aligned coaxially with the first rod 21 and extending opposite the latter from the collar 22.

This second threaded rod 23 is intended to be engaged through an orifice 6 formed in the sheet 4 (see FIG. 4), then screwed into the tapping of a second nut 7 welded on the periphery of this orifice 6 against the face outer 4A of this sheet 4 (the one facing the outside of the engine compartment).

To ensure the screwing of this second threaded rod 23 on the nut 7, the collar 22 has a polygonal external section (in this case octagonal) intended to cooperate with an end piece of complementary shape mounted on a screwing tool of the electric screwdriver type. .

The threading of this second rod 23 is advantageously of the self-tapping type in order to be able to screw it onto the nut 7, even when its tapping is covered with a layer of paint (such a scenario can arise when this nut 7 is welded before the cataphoresis of the body).

The second rod 23 advantageously has a length greater than the thickness of the nut 7 into which it is screwed, so that it can be used, after the establishment of the grounding stud 20, as a fixing point for another vehicle body located outside the engine compartment (that is to say on the external side of the sheet 4) such as for example a support for the accelerometer sensor of the front suspension shock absorber (not shown).

The distribution cup 30, illustrated alone in FIG. 3, advantageously came in one piece by molding from a thermoplastic material.

It comprises a circular base 31 surmounted by a plurality of peripheral slots in an arc of a circle 35 regularly angularly spaced and delimiting between them passage windows each intended to be crossed radially by the crimping end piece 43 of a terminal 40.

The base 31 is provided with an indexing hole 32 whose profile, here octagonal, is complementary to that of the external section of the collar 22 of the grounding stud 20, so that it can be fitted by correspondence of form.

The cup 30 further comprises axial retaining means for the lugs 40, constituted by elastically deformable tongues 37 extending at the top of the peripheral slots 35 and each projecting tangentially on either side of a said slot 35.

The spacing between the free ends opposite the tongues of two adjacent peripheral slots 35 is less than the width of the crimping end piece 43 of a terminal 40, so that the latter are capable of retaining this end piece 43 axially after it has been force-fitted between these two tabs 37.

The base 31 of the cup 30 also includes anti-shrinkage means able to cooperate by snap-fastening when it is interlocked with complementary means provided on the collar 22 of the grounding stud 20, so as to prevent its accidental dislocation.

These anti-shrinkage means comprise two elastic tabs 33 of small thickness arranged opposite that of the base 31 and projecting radially, diametrically opposite, over a small distance inside the indexing hole 32 from the face of this base 31 coming opposite the sheet 4 and opposite the slots 35.

These two tabs 33 are intended to snap into an annular clearance 24 formed on the collar 22 of the stud 20 at its face coming into contact with the sheet 4 and opposite the first threaded rod 21.

We will now describe the steps for setting up the earthing device according to the invention.

Initially, the operator performs, from inside the engine compartment and using an electric screwdriver cooperating with the collar 22, the screwing of the second threaded rod 23 of the grounding stud 20 on the 'nut 7 welded against the external face 4A of the sheet 4 located opposite this engine compartment.

Due to its reduced dimensions, such a screwdriver can be easily inserted into the engine compartment, unlike a welding head whose size is significantly larger.

Once this operation has been completed, the collar 22 forming the shoulder is pressed into abutment against the internal face 4B of the sheet metal 4 giving onto this engine compartment, as illustrated in the figure.

4.

The operator then pre-positions the lug (s) 40 on the distribution cup 30 by forcing and against the elastic tongues 37 their crimping ends 43 in the passage windows 36.

Once introduced, this or these lugs 40 are prevented from leaving this cup 30 by the slots 35 radially retaining their plates 41 and by the tongues 37 axially retaining their end pieces 43.

Consequently, the operator can calmly bring this cup 30 and the lugs 40 near the grounding stud 20, then successively thread the base 31 and the plates 41 along the first threaded rod 21 of this stud 20.

It must then force fit the indexing hole 32 of this base 31 on the collar 22 until the lugs 33 snap into the annular clearance 24, then operate the screwing of the nut 5 on this first threaded rod 21 of the stud 20 so as to rigidly press the lug (s) 40 between the collar 22 and this nut 5.

Once in place, the interlocking cooperation between the cup 30 and the collar 22 of the grounding stud 20 prevents any relative rotation between these two elements, the lug (s) 40 also being locked in rotation relative to the cup 40 thanks to the presence of slots 35.

According to variant embodiments not shown, the grounding device does not include a distribution cup such as 30, for example when a single terminal is intended to be fixed to the grounding stud 20.

According to other variant embodiments not shown, the external section of the collar of the grounding stud and the indexing hole of the base of the cup can have a different polygonal shape, for example triangular, square or even hexagonal.

According to yet other alternative embodiments not shown, the dispensing cup is different. The axial retaining means and / or anti-withdrawal may in particular be absent or shaped differently.

In general, it is recalled that the present invention is not limited to the embodiments described and shown, but that it encompasses any variant of execution within the reach of the skilled person.

Claims (10)

1. Device for grounding electrical terminals comprising a metal grounding stud (20) provided with a first threaded rod (21) and a collar (22) extending radially at the base of said first rod (21), said stud (20) being intended to be fixed against a metal wall (4) so that said collar (22) is pressed against a first face (4B) of said wall (4), said first threaded rod (21) being intended to cooperate with a first nut (5) to allow the fixing between said collar (22) and this nut (5) of at least one electric terminal (40) threaded beforehand on this first rod (21); characterized in that said stud (20) further comprises a second threaded rod (23) aligned coaxially with said first rod (21) and extending opposite to the latter from said collar (22), said second rod ( 23) being intended to be engaged through an orifice (6) formed in said wall (4), then screwed into the thread of a second nut (7) welded on the periphery of said orifice (6) against the second face (4A) of said wall (4), said collar (22) further having a polygonal outer section intended to cooperate with a screwdriver of complementary shape to ensure the screwing of said second threaded rod (23) on said second nut ( 7). 2. A grounding device according to claim 1, characterized in that said collar (22) has an octagonal external section. 3. Grounding device according to one of claims 1 or 2, characterized in that the threading of said second rod (23) of said stud (20) is of the self-tapping type. 4. Grounding device according to one of claims 1 to 3, characterized in that said second rod (23) has a length greater than the thickness of said second nut (7) so that it can be used, after the fitting of said stud (20), of attachment point for another member of the vehicle. 5. Earthing device according to one of claims 1 to 4, characterized in that it further comprises a distribution cup (30) comprising a base (31) surmounted by a plurality of peripheral slots (35) delimiting between them passage windows (36) each intended to be traversed radially by a part (43) of a said terminal (40), said base (31) being provided with an indexing hole (32) the profile is complementary to that of the polygonal external section of said collar (22), so that it can fit into it by shape correspondence. 6. A grounding device according to claim 5, characterized in that said distribution cup (30) came in one piece by molding from a thermoplastic material. 7. Earthing device according to one of claims 5 or 6, characterized in that said distribution cup (30) comprises axial retaining means (37) of the at least said terminal (40). 8. A grounding device according to claim 7, characterized in that said axial retaining means consist of elastically deformable tongues (37) extending at the top of said peripheral slots (35) and each projecting tangentially from one side and on the other side of a said slot (35), the spacing between the free ends opposite the tongues (37) of two adjacent peripheral slots (35) being less than the width of said part (43) of a said terminal (40). 9. Grounding device according to one of claims 5 to 8, characterized in that said distribution cup (30) comprises anti-shrinkage means (33) able to cooperate by snap-fastening when it is interlocked with means complementary (24) provided on said collar (22) of the grounding stud (20) to prevent its accidental dislocation. 10. Grounding device according to claim 9, characterized in that said anti-removal means comprises two elastic tabs (33) of smaller thickness than said base (31) and projecting radially, in diametrically opposite, to the inside said indexing hole (32) from the face of said base (31) turned towards said wall (4), said tabs (33) being intended to come 5 snap into an annular recess (24) formed on said collar (22) of the stud (20). 1/1 10 20