Patent Description:
In the sector of motor-vehicle assembly, particularly delicate is the operation of installation of a door on the body of a motor vehicle, in particular correct positioning of the door with respect to the body during the entire cycle of production of the motor vehicle itself.

During the process of assembly of a motor vehicle it may happen that the body and the doors of one and the same motor vehicle undergo treatments in physically distinct positions, so that there will exist a point of the cycle of assembly of the motor vehicle in which the assembly line forks into two sections: one section designed for processing the bodies and one section designed for processing the doors. Since it is not possible to carry out the operations of geometrical referencing of the doors after execution of the processing operations themselves, it is necessary to fix the doors to the body in the design position prior to the aforesaid processing operations, and then separate the doors from the body and rejoin them together in a subsequent step.

This creates considerable problems in so far as separation of the door from the body would lead to the loss of any geometrical reference in the case where the door were taken down in the simplest way possible, i.e., by mechanical separation of the entire hinge from the body itself.

To overcome the above technical constraint, known to the art are two solutions that are used selectively according to the type of hinge and type of door considered, and consist in the following:.

The main drawback of the first solution is represented precisely by the prearrangement of the dowels in so far as they add complexity to the working cycle and - for vehicles with frames made of composite material - impose the adoption of suction hoods on line for aspiration of the swarf of composite material generated at the moment of drilling of the seats for the dowels.

The drawback of the second solution is mainly represented by the limited operating range thereof; in particular, it is a solution scarcely practicable, or practicable with only modest results, on particular types of hinges, for example hinges for frameless doors or else hinges for doors with opening that is at least in part vertical (e.g., gullwing doors, folding doors, scissor doors) in so far as the operation of pulling out the pin requires that the assembly tolerances between the hinge elements and the pin itself should not be excessively stringent; otherwise, it would be unfeasible to slide out the pin on account of the small spaces between the hinge, the body, and the door due to the requirements imposed by the style of the car.

The object of the present invention is to overcome the technical problems mentioned previously. In particular, the object of the present invention is to provide an installation kit for a door hinge of a motor vehicle that will enable total removal of the hinge during the steps of separate processing of the body and the door and that will enable subsequent re-assembly of the door and of the hinge, without incurring in any of the aforementioned drawbacks and without requiring further line infrastructures.

The object of the present invention is achieved by an installation kit and an installation method having the features forming the subject of the ensuing claims, which form an integral part of the technical disclosure provided herein in relation to the invention.

The invention will now be described with reference to the annexed drawings, which are provided purely by way of non-limiting example and in which:.

The reference number <NUM> in <FIG> designates as a whole a hinge forming part of a kit <NUM> (<FIG>) for installation of a door on a body of a motor vehicle. The kit <NUM> comprises the hinge <NUM> and a positioning element <NUM>, which is illustrated in detail in <FIG>. Each of the two components will now be described in detail.

With reference to <FIG>, and <FIG>, the first hinge element <NUM> is configured to be fixed to a door D of a motor vehicle VL and is articulated to the second hinge element <NUM> about a hinge axis γ1, while the second hinge element <NUM> is configured to be fixed to a body BW of the motor vehicle VL and is configured to engage the positioning element <NUM> so as to establish the position of the hinge <NUM> and of the door D relative to the body BW.

In greater detail, the first hinge element <NUM> comprises a first fixing plate <NUM> configured for mechanical connection to the door D, for example by means of screws, and a stem <NUM> integral with the plate <NUM>. The stem <NUM> has a fork-shaped end <NUM>, which constitutes the interface with the second hinge element <NUM>.

The second hinge element <NUM> in turn comprises a second fixing plate <NUM> configured to be fixed on the body BW by means of screws: in the example considered here three screws at the vertices of a right triangle. Projecting from the flat plate <NUM> is an ensemble having a substantially fork-shaped structure and comprising a first shoulder <NUM> and a second shoulder <NUM>, between which the elements of the fork-shaped end <NUM> settle upon connection of the first hinge element to the second hinge element.

A hinge-pin <NUM> traverses the sequence of the ends <NUM>, <NUM>, and <NUM> defining the articulation between the two hinge elements. With reference once again to <FIG>, the hinge <NUM> comprises, in particular on the second hinge element <NUM>, a coupling element <NUM> configured to fit on the positioning element <NUM>. According to the invention, the coupling element <NUM> is provided as a fork-shaped plate, preferably comprising a first lateral tab <NUM> and a second lateral tab <NUM> separated from one another by a coupling groove <NUM>.

The side tabs <NUM>, <NUM> comprise, respectively, a first guide surface <NUM> and a second guide surface <NUM>, which both face the inside of the coupling groove <NUM> and are set on either sides of a third guide surface <NUM>, which delimits, with the aforesaid first guide surface <NUM> and second guide surface <NUM>, the coupling groove <NUM>.

With reference to <FIG>, the structure of the positioning element <NUM> will now be described. The positioning element <NUM> is basically configured as a substantially T-shaped piece or insert comprising a head portion <NUM> and a tongue <NUM> integral with the head portion <NUM> itself.

Provided within the tongue <NUM> is a through eyelet <NUM>, which has a shape elongated in a direction orthogonal to the head portion <NUM> and is comprised between a fourth guide surface <NUM> and a fifth guide surface <NUM>, which are opposite to one another and are configured to co-operate with the guide surfaces <NUM>, <NUM>, and a sixth guide surface <NUM>, which is configured to co-operate with the guide surface <NUM>.

With reference to <FIG>, there now follows a description of operation of the installation kit <NUM>, which comprises the hinge <NUM> and the positioning element <NUM>. A sequence of implementation of the kit itself will also be described.

The positioning element <NUM> is configured to be fixed to the body BW of the motor vehicle in a final position, which is reached by means of a two-stage operation. A first stage of this operation envisages pre-installation of the positioning element <NUM> on the body, without carrying out tightening thereof on the body. In greater detail, the element <NUM> is applied on the body BW in a position corresponding to the one theoretically resulting from the chain of tolerances imposed for installation of the door D according to design.

This means, with reference to <FIG>, that the positioning element <NUM> is fixed in a non-calibrated way on the body BW by means, for example, of screws <NUM>, <NUM>, which pass though the eyelet <NUM> and engage holes on the body BW, and engagement seats S42 coaxial to the holes on the body itself, where fixing is carried out without applying to the screws <NUM>, <NUM> a torque that would bring about tightening of the positioning element <NUM> on the body itself (i.e., the screws <NUM>, <NUM> are not tightened to the final torque value).

In the embodiment of <FIG>, the seats are represented as threaded bushings applied mechanically within the body BW (e.g., by welding or brazing), but in the case of bodies made of composite material reinforced with carbon fibres, the seats S42 are obtained by embedding threaded bushings within the composite material of the body itself.

Using a geometrical-reference tool operating with respect to the geometry of the body B, the door D is then positioned, complete with the elements <NUM> and <NUM> of the hinge (which are previously assembled and joined to the door D in a separate preparation area).

Once the door D has been positioned, it is possible to proceed to tightening the screws that engage the seats on the fixing plate <NUM> of the hinge element <NUM>, thus fixing the relative position between the door D and the body BW (geometrically conforming position).

At this point, also the positioning element <NUM> is brought into the geometrically preset position via definitive tightening of the screws <NUM>, <NUM> to the final torque value. This results in definitive and proper positioning of the positioning element <NUM> with respect to the body BW. In particular, the position of the guide surfaces <NUM>, <NUM> and <NUM>, which provide a geometrical reference of position along respective coordinates that are tangential to the planes of the surfaces <NUM>, <NUM>, <NUM> of the positioning element <NUM> is determined.

Reaching of the pre-set position of the positioning element <NUM> is achieved, in particular, at the moment of mating of the latter with the fork-shaped plate <NUM> on the flat plate <NUM> of the hinge element <NUM>: the fork-shaped plate <NUM> embraces the positioning element <NUM> laterally, receiving it within the groove <NUM>, and the guide surfaces <NUM>, <NUM> abut against the respective guide surfaces <NUM>, <NUM>, <NUM> (the surface <NUM> functions as a stop surface for mating) in such a way that the element <NUM> is referenced in position consistently with the fork-shaped plate and has the same precision as the hinge.

In general, setting up the kit <NUM> envisages that the co-operating pairs of guide surfaces (<NUM>, <NUM>; <NUM>, <NUM>; <NUM>, <NUM>) of the positioning element <NUM> and of the coupling element <NUM> abut against one another, making sure that the surfaces <NUM> and <NUM> abut in any case upon one another in so far as, in the specific embodiment of the kit <NUM> presented in the figures, they are the only ones that bear upon one another in a longitudinal direction.

It is in particular preferable to ensure simultaneous contact at three surfaces (i.e., all of the three pairs <NUM>, <NUM>; <NUM>, <NUM>; <NUM>, <NUM> involved), thus doubling the constraint on the longitudinal position (the triple contact is obtained by thrust exerted by the line operator on the hinge at the moment of positioning of the door).

Alternatively, instead of resorting to contact between the surfaces <NUM>/<NUM>, it is possible to resort to the contact between the surfaces <NUM>/<NUM> and <NUM>/<NUM> (where the surfaces <NUM>, <NUM> are located at the free ends of the side wings <NUM>, <NUM>, while the surfaces <NUM>, <NUM> are located at opposite ends of the head portion <NUM>, on the side of the tongue <NUM>).

To sum up, according to the invention a method for installation of the door D on the motor-vehicle body BW using the installation kit <NUM> is thus defined, the method comprising:.

At the end of this installation process, the door D is geometrically referenced with respect to the body BW, the hinge element <NUM> is geometrically referenced with respect to the hinge element <NUM> via the centring pin (it is possible to provide the hinge <NUM> with strict tolerances, it not being necessary to disassemble the latter), the positioning element <NUM> is geometrically referenced to the hinge element <NUM> via the mating surfaces <NUM>/<NUM><NUM>/<NUM> and <NUM>/<NUM>, and in turn also the positioning element <NUM> is geometrically referenced with respect to the body BW.

This makes it possible to check for proper operation (opening/closing) of the door D before the body BW and the door D are sent on to the subsequent processing steps, which envisage a separate treatment for the body BW and for the door D.

At this point, and unlike all the known solutions described at the outset, the hinge <NUM> can be simply detached from the body, keeping, however, the positioning element <NUM> fixed to the body BW in the pre-set position established at the moment of tightening of the screws <NUM>, <NUM>.

In this way, once the operations of treatment on the body BW and on the door D are completed, the door can be joined to the body simply by repeating the operation of coupling between the hinge <NUM> (hinge element <NUM>) and the positioning element <NUM>, i.e., once again engaging the fork-shaped plate <NUM> with the positioning element <NUM>, given that the final position of the hinge <NUM> will be the same as the one defined at the moment of geometrical referencing and fixing of the element <NUM>.

Thanks to the installation kit <NUM>, all the problems described at the outset are thus solved since it is no longer necessary to provide dowel pins for complete separation of the hinge <NUM> from the body BW, which in this case may be obtained without drawbacks of any sort given that the subsequent repositioning does not require any operation of tolerance repositioning thereof, nor is it required to carry out additional processing operations on the body BW, with associated complication of the line structures.

It is not even required to envisage pulling out the pin <NUM> thanks to the fact that the new coupling of the hinge <NUM> on the body BW may be obtained in an easy and fast way simply by engaging the positioning element <NUM> (which remains fixed on the body BW once it has been applied thereto), with the benefit inherent in the possibility of providing the hinge <NUM> with very strict tolerances between the hinge elements <NUM> and <NUM> and the pin <NUM>, and consequently with a high level of precision. In effect, once the position of the element <NUM> has been fixed at the moment of preliminary installation of the hinge <NUM>, the coupling element <NUM> engages the positioning element <NUM> so as to position the hinge <NUM> as a whole with respect to the body BW of the motor vehicle at the moment of fixing (this time definitive fixing) of the second hinge element <NUM> on the body BW of the motor vehicle VL.

Claim 1:
An installation kit (<NUM>) of a door (D) of a motor vehicle (VL), comprising:
- a hinge (<NUM>) including a first hinge element (<NUM>) and a second hinge element (<NUM>), the first hinge element (<NUM>) being articulated to the second hinge element (<NUM>) about a hinge axis (γ1); and
- a positioning element (<NUM>) configured to be fixed to a body (BW) of the motor vehicle (VL);
wherein:
- the first hinge element (<NUM>) is configured to be fixed to the door (D) of the motor vehicle (VL); and
- the second hinge element (<NUM>) is configured to be fixed to the body (BW) of the motor vehicle and comprises a coupling element (<NUM>) configured to engage said positioning element (<NUM>) so as to position the hinge (<NUM>) with respect to the body (BW) of the motor vehicle upon fixing the second hinge element (<NUM>) on the body (BW) of the motor vehicle (VL), and
wherein said positioning element (<NUM>) is a piece that can be fixed to the body of the motor vehicle, preferably by means of screws (<NUM>, <NUM>), the installation kit being characterized in that the coupling element of said second hinge element (<NUM>) is provided as a fork-shaped plate (<NUM>) configured to engage said positioning element (<NUM>).