Method for assembling lighting unit of motor vehicle and machine for implementing such method

Abstract

A method of assembling an automotive lighting unit (100) comprising one or more inner members (104) made of an opaque polymeric material, these inner members (104) being fixed against an inner surface of a rear housing (101) at respective contact areas or sections (105); the assembling method comprises the following steps: obtaining the rear shell (101); obtaining at least one internal lighting member (104) having at least one portion made of an opaque polymer material; placing said at least one internal lighting member (104) inside the rear housing (101), wherein said portion made of opaque polymeric material rests on the rear housing (101) in at least one contact section (105); and forming at least one laser welded joint (106) at the contact area (105) in order to rigidly secure the at least one internal lighting member (104) to the rear housing (101).

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to European patent applications No. 23199313.0, No. 23199334.6 and No. 23199296.7, all filed on September 25, 2023, the entire disclosures of which are incorporated herein by reference. Technical Field

[0003] The invention relates to a method for assembling a vehicle lighting unit and a machine for implementing the method.

[0004] More specifically, the invention relates to a method and a machine for welding a component made of opaque plastic material to the inside of a rear housing of a headlight or taillight of a car or similar motor vehicle. The following disclosure will make explicit reference to the use without thereby losing generality. Background Art

[0005] As is well known, the headlights or taillights of automobiles and similar motor vehicles are generally lighting devices that are specifically configured to be located at the front, rear or side of the vehicle and perform the functions of illuminating the area around the vehicle and / or signaling the vehicle's position, sudden deceleration of the vehicle and / or vehicle turning according to given photometric type approval standards.

[0006] Most taillights for automobiles and similar motor vehicles typically include: a rear shell of substantially rigid and opaque structure, which is substantially basin-shaped and constructed to be stably recessed into a compartment specially formed in the rear portion of the vehicle body; a front half shell of substantially rigid and transparent structure, which is separate and different from the rear shell, the front half shell being substantially complementary in shape to the mouth of the rear shell and generally arranged in a manner facing the exterior of the vehicle body to close the mouth of the rear shell; and a series of electric lighting assemblies, which are located inside the rear shell, each electric lighting assembly being immediately below a corresponding transparent or translucent sector of the front half shell so as to selectively backlight the overlying transparent or translucent sector of the front half shell.

[0007] Typically, each transparent or translucent sector of the front half shell is also uniquely associated with a specific light signal, so that the various lighting components present inside the hollow housing formed / defined by the front half shell and the rear shell are constructed to emit a light beam upon command, which light beam, once it emerges from the lighting unit through the corresponding transparent or translucent sector of the half shell, meets the photometric type approval criteria (light color and light distribution) determined for the light signal.

[0008] Currently, both the rear shell and the front half shell have an integral structure and are made by injection molding of polymer materials.

[0009] In more detail, the rear housing is entirely made of an opaque polymer material, whereas the front housing half is entirely or almost entirely made of a transparent and / or translucent polymer material.

[0010] Furthermore, in the latest headlights and taillights, the front half-shell is irremovably joined to the rear housing via a laser weld extending along the entire peripheral edge of the mouth of the rear housing.

[0011] The lighting assembly located inside the rear shell body typically uses a series of LEDs (the acronym for Light Emitting Diodes) as light sources, and typically also includes one or more reflector bodies and / or one or more light guide bodies, wherein the reflector body reflects the light generated by the LED toward the transparent or translucent sector of the facing front half shell, and the light guide body collects the light generated by the LED and guides it to the transparent or translucent sector of the facing front half shell through total internal reflection.

[0012] Additionally, these lighting assemblies typically also include filters, corrective optics, shielding masks and / or other active and / or passive optics capable of adapting the light beams emitted by the various LEDs to the photometric and aesthetic requirements associated with automotive use.

[0013] Finally, these lighting assemblies are also provided with a frame, brackets and / or other support elements that rest on the inner surface of the rear housing and are constructed to support one or more printed circuit boards that house LEDs, wires, one / more reflector bodies, one / more light guide bodies and / or other active and / or passive optical devices that help form each lighting assembly.

[0014] Currently, most of the components of the lighting assembly that contribute to forming a taillight (such as the reflector body, shielding mask, frame, bracket and / or other supporting elements) are made of opaque polymer materials and are fixed to the rear shell with the aid of a series of self-threading metal screws, most of which are inserted into the rear shell in a through-going manner from the outside of the lighting unit to the inside so that the head of the screw is arranged to rest against the outer surface of the shell.

[0015] Furthermore, some internal components of the automotive lighting unit may also be retained inside the rear housing by a series of shoulders, centering pins and / or snap-locking tabs obtained inside the rear housing. However, these centering and / or snap-locking systems are only used during assembly of the lighting unit, as they are generally not able to withstand the mechanical vibrations to which the automotive lighting unit is generally subjected during use.

[0016] Therefore, currently, self-tapping screws are the only means capable of securely fixing the main or large components of the automotive lighting unit in place inside the rear housing throughout the service life of the automotive lighting unit.

[0017] Therefore, today's assembly lines for automotive lighting units are currently provided with a series of automatic or semi-automatic screwdrivers that enable the operator working on the assembly line to place and screw the self-tapping screws into the rear housing as quickly as possible.

[0018] Unfortunately, although self-tapping screws are necessary to obtain the taillight, they make the assembly of the taillight relatively laborious and also significantly affect the overall weight and cost of the lighting unit. Since they are made of metal, self-tapping screws are some of the most expensive components of the lighting unit.

[0019] In addition, self-tapping screws occasionally jam in automatic screwdrivers, rendering the tool unusable, with all the problems that this entails. In fact, recovering an automatic or semi-automatic screwdriver may take several minutes, during which the assembly line must come to a standstill. Summary of the invention

[0020] The object of the invention is to eliminate or in any case minimize the use of self-tapping screws, thereby simplifying and speeding up the assembly of automotive lighting units.

[0021] In accordance with these objects, according to the present invention, there is provided a method for assembling a vehicle lighting unit as defined in claim 1 and preferably, but not necessarily, in any of the dependent claims.

[0022] Furthermore, according to the present invention, there is provided an assembly machine for automotive lighting units as defined in claim 10 and preferably, but not necessarily, in any of the dependent claims.

[0023] Finally, according to the present invention, there is provided a vehicle lighting unit as defined in claim 22 and preferably, but not necessarily, in any of the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention will now be described with reference to the accompanying drawings, which show non-limiting examples of implementation of the invention, in which:

[0025] Figure 1 is a schematic front view of an assembly machine for automotive lighting units obtained in accordance with the teachings of the present invention, with parts in section and parts removed for clarity;

[0026] Figure 2 is a perspective view of an automotive lighting unit obtained in accordance with the teachings of the present invention, with parts in section and parts removed for clarity;

[0027] Figure 3 yes Figure 2 a partially exploded perspective view of an automotive lighting unit shown with portions removed for clarity;

[0028] Figure 4 yes Figure 1 a perspective view of a portion of the machine shown with parts removed for clarity;

[0029] Figure 5 , Figure 6 and Figure 7 Schematically shows the Figure 1 Some steps of assembling the automotive lighting device of the machine shown;

[0030] Figure 8 yes Figure 1 a schematic side view of a first variant of an assembly machine for automotive lighting units shown, with parts in section and parts removed for clarity;

[0031] Fig. 9 yes Figure 1 Schematic front view of a second variant of an assembly machine for automotive lighting units is shown, with parts in section and parts removed for the sake of clarity. DETAILED DESCRIPTION

[0032] Reference Figure 1 and Figures 4 to 7 , reference numeral 1 denotes an entire automotive lighting unit assembly machine, which is suitable for performing laser welding of plastic parts.

[0033] In more detail, the machine 1 is specifically configured to laser weld at least a portion of components made of a polymer material directly on the rear shell of the automotive lighting unit 100, which components together form the automotive lighting unit 100 and are located inside the automotive lighting unit 100, or more precisely inside its rear shell.

[0034] The term “automobile lighting unit” refers to a lighting device that is constructed to be securely fixed to the front or rear of a body of a motor vehicle (not shown), and has the function of emitting light signals suitable for signaling / indicating the position of the vehicle and / or a sudden deceleration of the vehicle and / or a turn of the vehicle during driving and / or illuminating the area surrounding the vehicle.

[0035] In other words, the automotive lighting unit 100 is adapted to be fixed to the front or rear of a body of an automobile, van, truck, motorcycle or other similar motor vehicle to perform the function of a headlight or a taillight.

[0036] Optionally, the automotive lighting unit 100 may also be used to display illuminated logos and / or graphic or alphanumeric symbols.

[0037] Obviously, the automobile lighting unit 100 may also be arranged on the side of an automobile or other similar motor vehicle.

[0038] Preferably, the vehicle lighting unit 100 is also configured to be stably recessed into a vehicle body (not shown) and to face the outside of the vehicle body.

[0039] Reference Figure 2 and Figure 3 In particular, the automotive lighting unit 100 comprises: a rear shell 101, which has a substantially rigid and advantageously also substantially opaque structure to visible light, the rear shell 101 is concave in shape and is suitable for being firmly fixed to a vehicle body (not shown), preferably fixed to a seat specially obtained in the vehicle body; and a front half shell 102, which has a substantially rigid and also at least partially transparent structure to visible light, the front half shell 102 is separate and different from the rear shell 101, the front half shell 102 is roughly lens-shaped in shape and is firmly fixed to the rear shell 101 to close the mouth of the rear shell 101 so as to form an internally hollow rigid shell together with the rear shell 101.

[0040] Preferably, the front half shell 102 is also shaped / configured to face the outside of the vehicle body and / or substantially completely close the mouth of the rear shell 101 , thereby forming a closed internally hollow rigid shell together with the rear shell 101 .

[0041] In more detail, the rear housing 101 is preferably substantially shaped in the form of an advantageously oblong tub and / or has a nominal thickness preferably in the range between 1 mm (millimetres) and 4 mm (millimetres).

[0042] In addition, the rear housing 101 preferably has a unitary structure and is at least partially made of a polymer material. In other words, the rear housing 101 is partially made of a polymer material that is opaque to visible light, advantageously made via injection molding.

[0043] Similarly, the front half shell 102 is preferably of unitary construction and is at least partially made of a polymer material. In other words, the front half shell 102 is at least partially made of a transparent polymer material, advantageously made via injection molding.

[0044] Reference Figure 2 and Figure 3 In addition, the automotive lighting unit 100 further comprises a series of internal lighting components, which together form one or more lighting assemblies 103 , wherein each lighting assembly is located inside the rear housing 101 and is suitable for backlighting the front half housing 102 .

[0045] In the example shown, in particular the automotive lighting unit 100 or more precisely the rear housing 101 is preferably configured to be recessed into the rear part of a body of an automobile or other similar motor vehicle.

[0046] In other words, the automotive lighting unit 100 is preferably a tail light of an automobile or the like.

[0047] Obviously, in different embodiments, the vehicle lighting unit 100 may also be configured to be simply cantilevered and fixed on the front, side or rear of the vehicle body (not shown).

[0048] Preferably, the rear housing 101 is also provided on the outer surface with a series of bushings and / or other fixing attachments that allow the rear housing 101 to be rigidly attached to a vehicle body (not shown).

[0049] In the example shown, in particular, the rear housing 101 is preferably made substantially entirely of an opaque polymer material.

[0050] In more detail, in the example shown, the rear housing 101 is preferably made of acrylonitrile butadiene styrene (ABS) or other polymer material, advantageously filled with carbon black or other opaque pigment.

[0051] Obviously, in different embodiments, the rear shell 101 can also be shaped and / or constructed to be at least partially recessed into a seat obtained specifically in the front or side of the vehicle body (not shown), or simply cantilevered fixed to the front, side or rear of the vehicle body.

[0052] Reference Figure 2 and Figure 3 On the other hand, the front half shell 102 is provided with one or more transparent or translucent sectors (i.e. sectors that allow visible light to pass through, which sectors may also optionally have different colors from each other), and is preferably rigidly fixed to the rear housing 101 in a substantially fluid-tight manner. Obviously, the front half shell 102 may also include one or more opaque sectors adjacent to the one or more transparent or translucent sectors.

[0053] In addition, the front half shell 102 preferably has a shape substantially complementary to the mouth of the rear shell 101, and is preferably firmly fixed to the rear shell 101 along the peripheral edge of the mouth.

[0054] Preferably, the front half shell 102 is also directly welded to the rear shell body 101 .

[0055] In more detail, the front half shell 102 is preferably directly welded to the rear shell 101 substantially seamlessly along the entire peripheral edge of the mouth of the rear shell 101 .

[0056] In the example shown, in particular, the front half shell 102 is preferably made of transparent polycarbonate (PC), transparent polymethyl methacrylate (PMMA) or other transparent or translucent polymer materials.

[0057] Preferably, the front half shell 102 is also welded to the rear shell 101 in a known manner via laser welding, vibration welding or hot plate welding.

[0058] Reference Figure 2 and Figure 3 , one or more lighting components 103 are located inside the rear shell 101, preferably, each lighting component 103 is aligned with the corresponding transparent or translucent sector of the front half shell 102, and each lighting component 103 is suitable for emitting light so as to backlight the transparent or translucent sector of the facing half shell 102, preferably individually and independently of other lighting components 103.

[0059] In more detail, the one or more lighting assemblies 103 are preferably electrically powered lighting assemblies adapted to emit light on command and which are also advantageously housed entirely within the rear housing 101 .

[0060] Preferably, the / each lighting assembly 103 is also configured to emit, on command, a light beam which, upon exiting the automotive lighting unit 100 through the front half-shell 102, meets photometric type approval standards (light colour and distribution) determined for a given light signal.

[0061] Obviously, one or some lighting assemblies 103 may also emit light beams which do not meet or have to meet the photometric type approval criteria.

[0062] For more details, refer to Figure 2 , Figure 3 and Figures 5 to 8 The automotive lighting unit 100 further includes a series of internal lighting components that are separate and distinct from the rear housing 101 and the front half housing 102 , and that together form one or more lighting assemblies 103 .

[0063] Furthermore, some of these interior lighting components are substantially rigid and are at least partially made of a polymer material that is opaque to visible light.

[0064] In addition, one or more of these internal lighting components made of opaque polymer material (represented by reference numeral 104 hereinafter) are arranged so that the portion made of opaque polymer material rests on the inner surface of the rear shell 101 at a specific mutual contact area or section 105, and is rigidly and irremovably fixed directly to the same rear shell 101 by means of at least one laser welded joint 106 formed at (one or more) said mutual contact areas 105.

[0065] Obviously, the internal lighting member(s) 104 may also be made completely of a polymer material that is opaque to visible light.

[0066] Preferably, the contact area(s) 105 between the rear housing 101 and the interior lighting member 104 are also substantially planar.

[0067] On the other hand, the laser welded joint 106 is preferably substantially point-shaped. Obviously, the laser welded joint 106 can also have a line shape.

[0068] In other words, each internal lighting component 104 is arranged so that the portion made of the opaque polymer material rests on the inner surface of the rear shell 101 at at least one contact area or section 105, and is rigidly and irremovably fixed to the rear shell 101 via at least one laser welded joint 106 formed at the contact area or section 105.

[0069] Therefore, at the mutual contact area 105, the rear housing 101 and the internal member 104 are both made of a polymer material that is opaque to visible light.

[0070] As will be apparent, a laser weld joint 106 is formed in the contact region 105 across a portion of the rear housing 101 and an adjacent portion of the interior lighting member 104, both portions being made of an opaque polymer material.

[0071] Preferably, the rear housing 101 and the internal lighting member(s) 104 at the contact area 105 are made of an opaque polymer material having laser beam absorption coefficients μ (Beer-Lambert law) different from each other.

[0072] More specifically, at the contact area 105 , the difference between the laser beam absorption coefficients μ of the respective opaque polymer materials of the rear housing 101 and the interior lighting member 104 is preferably greater than 35% of the laser beam absorption coefficient μ having a larger value.

[0073] In the example shown, in particular, the inner component(s) 104 are preferably of unitary construction and are preferably made entirely of a polymer material that is opaque to visible light, advantageously via injection molding.

[0074] In addition, one or more internal lighting components 104 preferably include, for example, one or more reflector bodies and / or shielding masks and / or correction lenses and / or diffuser filters and / or colored lens filters and / or reflectors and / or fixed frames and / or brackets or other auxiliary support structures, which are at least partially made of a polymer material that is opaque to visible light and are arranged so that the portion made of the opaque polymer material rests on the inner surface of the rear shell 101.

[0075] Reference Figure 2 and Figure 8 Preferably, the rear housing 101 and the / each internal lighting component 104 are also shaped / configured to achieve shape coupling in the mutual contact area 105 .

[0076] In more detail, the rear housing 101 and the inner member 104 are preferably shaped / configured to achieve a male-female coupling in the mutual contact area(s) 105 .

[0077] More specifically, the / each internal component 104 is preferably provided with one or more protruding fixing pins 107, apparently made of an opaque polymer material, wherein each fixing pin 107 extends parallel to a predetermined insertion direction d0 and is suitable for arranging its distal end portion to abut against the inner surface of the rear shell 101 at the contact area 105.

[0078] Furthermore, the laser weld joint 106 is preferably located at the distal end of the fixing pin 107 .

[0079] Furthermore, the / each fixing pin 107 is preferably also suitable for engaging a corresponding receiving seat 108 , which is preferably substantially cup-shaped and obtained directly on the rear housing 101 or more precisely on the bottom of the rear housing 101 .

[0080] Preferably, the mutual contact area 105 is also located inside the receiving seat 108 .

[0081] In more detail, the distal end of the fixing pin 107 is preferably adapted to rest stably on the bottom of the receiving seat 108 , so that the contact area or section 105 is preferably located on the bottom of said receiving seat 108 .

[0082] In even more detail, the receiving seat 108 preferably has a shape that is substantially complementary to the shape of the distal end of the fixing pin 107 .

[0083] Obviously, in different embodiments, the fixing pin can be cantilevered from the bottom of the rear housing 101 and the receiving seat can be located on the internal lighting component(s) 104 .

[0084] In this alternative embodiment, it is evident that the protruding securing pin is provided with a central blind hole, the bottom of which is at a short distance from the contact area 105 .

[0085] In other words, in this alternative embodiment, the securing pin is hollow inside.

[0086] Optionally, the automotive lighting unit 100 may also include one or more cameras and / or one or more photosensitive sensors and / or one or more radar devices and / or one or more LiDAR (acronym for Light Detection and Ranging) instruments and / or other auxiliary electronic devices, which are also housed inside a rigid housing formed / defined by the rear shell 101 and the front half shell 102.

[0087] Even the one or more auxiliary electronic devices preferably include or may include one or more internal lighting components 104, which are at least partially made of opaque polymer material, arranged so that the part / portion made of opaque polymer material rests on the inner surface of the rear shell 101 in at least one contact area or section 105, and is fixed to the rear shell 101 in a rigid and irremovable manner by means of at least one laser welded joint 106 formed at the contact area or section 105.

[0088] Reference Figure 1 and Figures 4 to 8 , the assembly machine 1 of the automotive lighting unit is suitable for forming one or more laser welded joints 106, which are suitable for fixing (one or more) internal components 104 directly to the rear shell 101, or more precisely directly to the inner surface of the rear shell 101, in a rigid and non-removable manner at (one or more) contact areas or sections 105.

[0089] The welding machine 1 firstly comprises: a workpiece-carrying fixture 2, which is constructed to temporarily accommodate and advantageously also retain a rear shell 101 having one or more internal components 104 inside; and a laser device 3, which is suitable for generating at least one laser beam r according to a command and directing it toward / at the rear shell 101 placed in the workpiece-carrying fixture 2 at this time.

[0090] In more detail, the workpiece carrying fixture 2 is configured to temporarily house and advantageously also retain a rear housing 101 having one or more internal lighting components 104 resting on an inner surface of the rear housing 101 at respective contact areas or sections 105 .

[0091] In other words, the workpiece carrying fixture 2 is suitable for accommodating a rear shell 101, which is provided with at least one sector made of opaque polymer material and at least one internal component 104, which is in turn located inside the rear shell 101 and is provided with at least one portion made of opaque polymer material, which at least one portion rests on the sector made of opaque polymer material of the rear shell 101 in at least one contact area or section 105.

[0092] The laser device 3 is in turn adapted to generate at least one laser beam r and direct it towards the workpiece carrying fixture 2 in a direction intersecting at least one contact area 105 between the rear housing 101 and the internal lighting member 104 so as to form at least one laser weld joint 106 at said contact area 105 .

[0093] Preferably, said at least one laser beam r also has a wavelength λ advantageously higher than 400 nm (nanometers) and more conveniently higher than 900 nm (nanometers).

[0094] In addition, the workpiece carrying fixture 2 and the laser device 3 as a whole are constructed so that (one or more) laser beams r pass through the thickness of the rear shell 101 accommodated / fixed in the workpiece carrying fixture 2 and reach (one or more) contact areas 105 between the rear shell 101 and (one or more) internal components 104.

[0095] In other words, the workpiece carrier fixture 2 and the laser device 3 as a whole are constructed so that the (one or more) laser beams r pass through the workpiece carrier fixture 2 and reach / impact the outer surface 101e of the rear shell 101 accommodated in the workpiece carrier fixture 2 before reaching the (one or more) contact areas 105 between the rear shell 101 and the (one or more) internal lighting components 104.

[0096] Obviously, the outer surface 101 e is a portion of the surface of the rear housing 101 that remains outside the automotive lighting unit 100 when the front half shell 102 is welded or otherwise fixed to the mouth of the rear housing 101 .

[0097] In more detail, the workpiece carrying fixture 2 is provided with a seat adapted to accommodate the rear housing 101 having one or more internal lighting components 104 therein.

[0098] In addition, the workpiece carrying fixture 2 is also provided with one or more internal laser paths (preferably in the air), wherein each internal laser path is constructed to allow (one or more) laser beams r to pass through the workpiece carrying fixture 2 with essentially no energy loss or minimal energy loss until reaching the seat accommodating the rear shell 101 and the rear shell 101 located therein.

[0099] In other words, the / each internal laser path of the workpiece carrier fixture 2 is constructed to allow (one or more) laser beams r of the laser device 3 to pass through the workpiece carrier fixture 2 substantially without energy loss until reaching the outer surface 101e of the rear shell 101 fixed in the workpiece carrier fixture 2.

[0100] In more detail, the / each internal laser path extends through the workpiece carrier fixture 2 to a receiving seat intended to accommodate the rear shell 101, is substantially aligned with the contact area 105 between the rear shell 101 and the internal component 104, and is constructed to allow (one or more) laser beams r of the laser device 3 to pass through the workpiece carrier fixture 2 to the receiving seat substantially without energy loss.

[0101] The laser device 3 is in turn coupled to the workpiece carrying fixture 2 such that the laser beam(s) r travels through the internal laser path(s) of the workpiece carrying fixture 2 to the receiving seat of the rear housing 101 .

[0102] Therefore, the laser beam(s) r of the laser device 3 reaches the rear housing 101 , or more precisely, the bottom of the rear housing 101 , without engaging / passing through the mouth of the rear housing 101 .

[0103] Preferably, the machine 1 further comprises a locking assembly 4 adapted to fix and / or press one or more internal lighting members 104 present inside the rear housing 101 fixed in the workpiece carrying fixture 2 onto the inner surface of the rear housing 101 .

[0104] In more detail, the locking assembly 4 is capable of moving away from and toward the workpiece carrier fixture 2, and vice versa, so as to be selectively coupled with the workpiece carrier fixture 2 to fix and / or press one or more internal lighting components 104 present inside the rear shell 101 onto the inner surface of the rear shell 101 accommodated in the workpiece carrier fixture 2.

[0105] In other words, the locking assembly 4 is constructed to freely enter the rear shell 101 temporarily accommodated in the workpiece carrying fixture 2 through the mouth of the rear shell 101, and there fix and / or press at least a portion of (one or more) internal lighting components 104 present inside the rear shell 101 against the inner surface of the rear shell 101 at the relevant contact / support area or section 105.

[0106] Reference Figure 1 and Figures 4 to 8In particular, the workpiece-carrying fixture 2 comprises: a workpiece-carrying template 5 having a basically non-deformable structure, the workpiece-carrying template 5 is preferably made of a metal material and is provided with a compartment 5a, which is shaped / constructed to accommodate a rear shell 101 and has a concave surface accessible from the outside; and preferably, the workpiece-carrying fixture 2 also includes one or more locking components or devices (not visible in the figure) that are advantageously electrically or pneumatically operated, which are suitable for selectively locking / fixing the rear shell 101 in the receiving compartment 5a of the workpiece-carrying template 5.

[0107] In more detail, the receiving compartment 5a of the workpiece carrying template 5 is constructed to accommodate a rear shell 101 having one or more internal lighting components 104 internally, and is provided with an access opening at the top, through which the rear shell 101 is inserted into and removed from the compartment 5a.

[0108] Preferably, the receiving compartment 5 a of the workpiece-carrying template 5 also has a shape that is substantially complementary to the shape of the rear housing 101 .

[0109] In addition, the workpiece-carrying template 5 is provided with one or more (advantageously in the air) internal through-channels 7, each of which extends through the body of the workpiece-carrying template 5 to the receiving compartment 5a, and is shaped / constructed to allow one or more laser beams r emitted by the laser device 3 to freely pass through the workpiece-carrying template 5 and reach the rear shell 101 engaged with the receiving compartment 5a.

[0110] In more detail, the / each internal through passage 7 is configured to allow one or more laser beams r emitted by the laser device 3 to pass through the workpiece-carrying template 5 substantially without energy loss and reach the outer surface 101 e of the rear housing 101 .

[0111] Furthermore, the / each through channel 7 of the workpiece-carrying template 5 terminates inside the receiving compartment 5a so as to be locally substantially aligned with a corresponding contact area or section 105 between the rear housing 101 engaging the receiving compartment 5a and an internal component 104 present inside the rear housing 101 .

[0112] The laser device 3 is suitable for guiding (one or more) laser beams r through (one or more) internal through channels 7 of the workpiece-carrying template 5 toward the receiving compartment 5a of the workpiece-carrying template 5, so that the / each laser beam r passes through the thickness of the rear shell 101 engaged with the receiving compartment 5a to reach the corresponding contact area 105.

[0113] For more details, refer to Figure 4 , Figure 7 and Figure 8The / each internal through passage 7 of the workpiece-carrying template 5 preferably terminates at the bottom of the receiving compartment 5a of the workpiece-carrying template 5 so as to be locally aligned with the overlying contact / support area 105 between the rear housing 101 and the internal lighting component 104.

[0114] In the example shown, in particular, the / each through channel 7 of the workpiece-carrying template 5 is preferably essentially composed of a through hole, an opening or a straight duct, which passes through the bottom of the receiving compartment 5a of the workpiece-carrying template 5 and is locally aligned with a corresponding contact / support area or section 105 present inside the rear shell 101 temporarily accommodated in the receiving compartment 5a of the workpiece-carrying template 5.

[0115] The / each internal through-channel 7 or more precisely the / each through-hole, opening or rectilinear duct of the workpiece-carrying template 5 is therefore situated in the workpiece-carrying template 5 on the side opposite to the mouth of the receiving compartment 5a.

[0116] Special reference Figure 4 , Figure 7 and Figure 8 The laser device 3 preferably comprises: at least one electric laser source 10 capable of emitting a high-power laser beam on command, the laser beam advantageously having a predetermined and substantially constant intensity and / or emission spectrum; and one or more optical fibers 11, each of which terminates in an internal laser path of the workpiece-carrying fixture 2 and is optically coupled to the laser source 10 so as to guide the laser beam to the internal laser path.

[0117] In other words, each optical fiber 11 terminates in a corresponding inner through-going passage 7 of the workpiece-carrying template 5 and is optically coupled to the laser source 10 in order to guide the laser beam emitted by the laser source 10 to the inner through-going passage 7 .

[0118] Preferably, moreover, the distal end of the / each optical fiber 11 is adapted to direct / guide its laser beam inside the workpiece carrying fixture 2 towards a corresponding contact area or section 105 between the rear housing 101 and the inner member 104 .

[0119] In other words, the distal end of the optical fiber 11 is suitable for directing its laser beam through the associated through-channel 7 of the workpiece-carrying template 5 towards the receiving compartment 5 a of the workpiece-carrying template 5 .

[0120] Preferably, the laser source 10 is also adapted to emit a laser beam having a nominal power higher than 10 Watts and / or a wavelength λ0 preferably higher than 400 nm (nanometers) and more conveniently higher than 900 nm (nanometers).

[0121] In addition, for the / each optical fiber 11, the laser device 3 preferably also includes a beam adjustment device 12, which is located downstream of the optical fiber 11 so as to be passed through by the laser beam r coming out of the optical fiber 11, and the beam adjustment device 12 is constructed to collimate and advantageously also focus the laser beam r guided toward the corresponding contact area or section 105 between the rear shell 101 and the internal component 104.

[0122] In other words, the / each beam adjustment device 12 is locally aligned with the corresponding through channel 7 of the workpiece carrying fixture 2, and is suitable for guiding the laser beam r emerging from the optical fiber 11 and entering the through channel 7 of the facing workpiece carrying fixture 2 toward the contact area 105 locally aligned with the through channel 7.

[0123] In more detail, the / each beam conditioning device 12 preferably comprises one or more lenses, advantageously of meniscus and / or plano-convex type, arranged one after the other to be passed through by the laser beam r emerging from the optical fiber 11 .

[0124] Reference Figure 8 Preferably, the laser device 3 is also configured to focus / concentrate the laser beam r directed toward the / each contact area 105 at a predetermined point in space (hereinafter referred to as the focus P), the focus P being located outside the internal laser path of the workpiece carrier fixture 2, inside the workpiece carrier fixture 2 and at the rear (downstream) of the contact area 105 between the rear housing 101 and the internal member 104. Preferably, the distance f between the focus P and the contact area 105 is less than 3 mm (millimeters), and advantageously also greater than 0.2 mm (millimeters).

[0125] In other words, the focus point P is located on the opposite side of the contact area 105 with respect to the origin of the laser r (or more precisely, with respect to the laser device 3 ) and is spaced apart from said contact area 105 .

[0126] Obviously, the laser weld joint 106 will always be formed at the contact area 105 .

[0127] In more detail, the laser device 3 is preferably provided with an optical focusing system, which is constructed to shape the laser beam r directed toward the / each contact area 105 essentially into the form of a cone, and the distance f between the focus P or more precisely the apex of the cone and the contact area 105 is preferably between 0.2 mm (millimeter) and 2 mm (millimeter), and more advantageously between 0.5 mm (millimeter) and 1.5 mm (millimeter).

[0128] Obviously, the laser beam r is formed into a cone shape before reaching the outer surface 101 e of the rear housing 101 accommodated in the workpiece carrying jig 2 .

[0129] However, in a less complex embodiment, the focus point P may be located at the contact area 105 .

[0130] Reference Figure 8 In the example shown, in particular, the / each beam adjustment device 12 is preferably constructed to focus the laser beam r passing through the device at a focal point P, which is located inside the receiving compartment 5a of the workpiece-carrying template 5 and is spaced apart from the contact area 105 to the rear of the contact area 105 towards which the laser beam r is directed.

[0131] Furthermore, the / each beam adjusting device 12 is preferably also configured such that the laser beam r forms a cone having an opening angle advantageously in the range between 10° and 90° before reaching the outer surface 101 e of the rear housing 101 .

[0132] Reference Figure 1 and Figures 4 to 8 In the example shown, in particular, the workpiece-carrying fixture 2 is preferably provided with a plurality of internal through-going channels 7 .

[0133] The laser device 3 is preferably provided with a bundle of optical fibers 11 which terminate at the individual through-channels 7 of the workpiece-carrying fixture 2 or more precisely the workpiece-carrying template 5 and are optically coupled to a laser source 10 in order to split and guide the high-power laser beam to the individual through-channels 7 of the workpiece-carrying template 5.

[0134] In more detail, the bundle of optical fibers 11 is preferably optically coupled to the laser source 10 so as to split the high power laser beam into substantially equal parts between the individual optical fibers 11 of the bundle.

[0135] Obviously, in different embodiments, a bundle of optical fibers 11 can be coupled to the laser source 10 so as to distribute the laser beam emitted by the laser source 10 in a differential manner among the individual optical fibers 11 of the bundle of optical fibers. For example, a higher laser power can be directed toward an optical fiber 11 whose distal end is very far from the corresponding contact area or section 105 between the rear housing 101 and the inner member 104.

[0136] On the other hand, the distal end of each optical fiber 11 is preferably firmly coupled to a corresponding beam adjustment device 12, which is aligned with or placed at the relevant through-channel 7 of the workpiece-carrying fixture 2, and is constructed to guide the laser beam r coming out of the optical fiber 11 toward a contact area or section 105 located downstream of the internal through-channel 7.

[0137] In addition, the / each beam adjustment device 12 is preferably firmly anchored to the workpiece-carrying fixture 2, or more precisely to the workpiece-carrying template 5, and is advantageously also constructed to at least partially engage with the relevant through channel 7 of the workpiece-carrying fixture 2, or more precisely with the relevant through hole, opening or straight channel present in the body of the workpiece-carrying template 5.

[0138] Reference Figure 1 and Figures 6 to 8 The locking assembly 4 is preferably located in front of the workpiece carrier fixture 2, or more precisely in front of a seat present on the workpiece carrier fixture 2 and accommodating the rear housing 101, and can be moved substantially linearly away from and towards said workpiece carrier fixture 2, and vice versa.

[0139] In more detail, the locking assembly 4 is preferably located in front of the mouth of the receiving compartment 5a of the workpiece-carrying template 5 and is able to move substantially linearly away from and towards said compartment 5a.

[0140] In addition, the locking assembly 4 preferably includes a locking template 13 having a substantially non-deformable structure, which is advantageously made of a metal material and is provided with one or more formed protrusions 13a, wherein each formed protrusion 13a is formed to freely enter the rear shell 101 temporarily accommodated in the workpiece carrying fixture 2 through the mouth of the rear shell 101, and to firmly fix and / or press the corresponding internal component 104 against the inner surface of the rear shell 101 at the relevant contact area or section 105.

[0141] In more detail, the locking template 13 is preferably provided with one or more shaped protrusions 13a which extend cantilevered parallel to the direction d in which the locking assembly 4 moves away from and towards the workpiece carrying fixture 2, and vice versa.

[0142] Preferably, the distal end of each shaped projection 13a of the locking template 13 has a shape that is substantially complementary to the portion of the internal lighting member 104 against which the shaped projection 13a is designed to rest.

[0143] In more detail, the (one or more) formed protrusions 13a of the locking template 13 are preferably shaped / constructed to be arranged on the (one or more) corresponding internal lighting components 104 present inside the rear shell 101, each of which is abutted against the rear of the corresponding fixing pin 107 of the internal lighting component 104.

[0144] Optionally, the locking assembly 4 may also preferably comprise a pneumatically operated pressing member mounted on the locking template 13 and adapted to apply a pushing force / pressure to the internal lighting member 104 on which the shaped protrusion(s) 13a rest.

[0145] Reference Figure 1 and Figures 4 to 8 In the example shown, in particular, the workpiece carrying fixture 2 and the locking assembly 4 are preferably arranged spaced apart from each other, vertically aligned with each other, and preferably capable of being moved away from and towards each other in a substantially linear manner.

[0146] In more detail, the workpiece carrier template 5 is preferably oriented with the mouth of the receiving compartment 5a turned upward so that the internal component(s) 104 are held in place by gravity inside the rear housing 101 temporarily housed therein.

[0147] The locking assembly 4 or more precisely the locking template 13 is again preferably arranged at a distance above the workpiece carrier fixture 2 or more precisely above the workpiece carrier template 5 so that the shaped projection(s) 13a are turned downwards, ie towards the workpiece carrier template 5 .

[0148] Preferably, the locking assembly 4 or more precisely the locking template 13 is still stationary in space, while the workpiece-carrying fixture 2 or more precisely the workpiece-carrying template 5 and advantageously at least a portion of the laser device 3 are able to move vertically away from the locking assembly 4 or more precisely away from the locking template 13 and towards the locking assembly 4 or more precisely towards the locking template 13.

[0149] Obviously, in different embodiments, the locking assembly 4 or more precisely the locking template 13 can be moved linearly away from and towards the workpiece-carrying fixture 2, while the workpiece-carrying fixture 2 remains stationary in space.

[0150] Reference Figure 1 , in particular, the machine 1 for automotive lighting unit assembly is preferably provided with a rigid support frame 20 configured to rest stably on the ground and optionally also to be rigidly anchored to the ground.

[0151] The workpiece carrying fixture 2 and the locking assembly 4 are preferably located on the support frame 20, one above the other, in vertical alignment with each other.

[0152] In more detail, the locking assembly 4 is preferably fixed on top of the supporting frame 20 so that the locking template 13 or more precisely the shaped protrusion(s) 13a of the locking template 13 are turned downwards.

[0153] On the other hand, the workpiece carrying fixture 2 is preferably fixed to the support frame 20 spaced apart below the locking assembly 4 so that the mouth of the receiving compartment 5a of its workpiece carrying template 5 is turned upward and it can be moved vertically away from and toward the locking assembly 4.

[0154] The laser device 3 is in turn preferably located on a support frame 20 below the workpiece carrier 2 or, more precisely, below the workpiece carrier template 5 .

[0155] Furthermore, the assembly machine 1 for automotive lighting units preferably also comprises: advantageously pneumatically or hydraulically operated movement means 21 suitable for vertically moving the workpiece-carrying fixture 2 away from and towards the locking assembly 4 ; and electronic control means 22 suitable for commanding the movement means 21 .

[0156] In more detail, the mobile device 21 is suitable for moving in a raised position (see Figure 1 , Figure 6 , Figure 7 and Figure 8 ) and lowered position (see Figure 1 and Figure 5 ) between the workpiece-carrying fixture 2, in the raised position, the workpiece-carrying template 5 is at a predetermined minimum distance from the locking template 13 of the locking assembly 4, and in the lowered position, the workpiece-carrying template 5 is at a predetermined maximum distance from the locking template 13 of the locking assembly 4.

[0157] In the raised position, the (one or more) formed protrusions 13a of the locking template 13 enter the interior of the rear shell 101 housed in the workpiece carrying fixture 2 so as to reach at least a portion of the (one or more) internal components 104 present inside the rear shell 101 at (one or more) associated contact areas or sections 105 and press them against the inner surface of the rear shell 101.

[0158] In the lowered position, the (one or more) formed protrusions 13a of the locking template 13 are oppositely away from the workpiece-carrying template 5 so as not to hinder or rather facilitate the removal and insertion of the rear shell 101 from the compartment 5a of the workpiece-carrying template 5.

[0159] In more detail, in the example shown, the support frame 20 preferably has a portal structure and is therefore provided with at least one pair of vertical columns and an upper crossbeam extending substantially horizontally and bridge-like between the upper ends of the vertical columns.

[0160] The locking assembly 4 is preferably rigidly fixed to the upper crossbeam of the support frame 20. On the other hand, the workpiece carrying fixture 2 is preferably fixed above a movable platform, which is arranged to be spaced below the upper crossbeam and is advantageously coupled to the vertical uprights of the support frame 20 in a vertically slidable manner.

[0161] On the other hand, the moving device 21 preferably comprises a pair of double-acting hydraulic cylinders or the like, each of which is arranged in a vertical position beside a corresponding vertical column of the support frame 20 and is suitable for raising and lowering the movable platform accommodating the workpiece carrying fixture 2 on command.

[0162] Obviously, in different embodiments, the movement system of the machine 1 may move the locking assembly 4 vertically away from and towards the workpiece-carrying fixture 2 , or may move both the workpiece-carrying fixture 2 and the locking assembly 4 vertically.

[0163] The assembly of the automotive lighting unit 100 first comprises a step of obtaining the rear housing 101, preferably via injection molding; and a step of producing at least one interior lighting component 104, preferably via injection molding, which has at least one portion / part made of an opaque polymer material. Preferably, the rear housing 101 also has a structure that is substantially opaque to visible light, i.e., it is advantageously made of an opaque polymer material.

[0164] After the rear shell 101 and (one or more) interior lighting components 104 have been obtained, the assembly of the automotive lighting unit 100 includes the following steps: placing the at least one interior lighting component 104 inside the rear shell 101 so that the part / portion made of the opaque polymer material rests on the inner surface of the rear shell 101 in at least one contact area or section 105; and then forming at least one laser welded joint 106 at the contact area or section 105 so as to fix the at least one interior lighting component 104 to the rear shell 101 in a rigid and essentially non-removable manner.

[0165] In addition, the step of forming the at least one laser welding joint 106 requires guiding at least one laser beam r toward the outer surface 101e of the rear shell 101, so that the laser beam r passes through the local thickness of the rear shell 101 to reach the contact area 105 between the rear shell 101 and the internal lighting component 104, or more precisely, to the part / portion of the internal lighting component 104 made of opaque polymer material.

[0166] Preferably, at the contact area 105 , a laser beam absorption coefficient μ of the opaque polymer material forming the rear housing 101 is smaller than a laser beam absorption coefficient μ of the opaque polymer material forming the internal lighting member 104 .

[0167] More specifically, the difference between the laser beam absorption coefficient μ of the opaque polymer material forming the rear housing 101 and the laser beam absorption coefficient μ of the opaque polymer material forming the interior lighting member 104 is preferably greater than 35% of the laser beam absorption coefficient μ of the opaque polymer material forming the interior lighting member 104 .

[0168] In other words, the laser beam absorption coefficient μ of a piece first traversed by the laser beam r is preferably lower, advantageously at least 35% lower, than the laser beam absorption coefficient μ of a piece second traversed by the same laser beam r.

[0169] In more detail, the step of forming the at least one laser welding joint 106 requires directing one or more laser beams r toward the contact area 105 through the entire thickness of the rear shell 101, so that the (one or more) laser beams r (only) reach the vicinity of the contact area 105 and temporarily heat the polymer material near the contact area 105 to a melting temperature.

[0170] The / each laser weld joint 106 is thus made across the rear housing 101 and the interior lighting component 104 .

[0171] In more detail, the step of forming the at least one laser welding joint 106 requires directing one or more laser beams r toward the outer surface 101e of the rear shell 101 within a predetermined time interval that is advantageously less than 30s (seconds), so that the (one or more) laser beams r can pass through the entire thickness of the rear shell 101 and reach the contact area or section 105.

[0172] Once the contact area or section 105 has been reached, the laser beam(s) r heats (only) the polymer material located in the vicinity of the contact area or section 105 in order to temporarily bring it to a melting / softening temperature.

[0173] Subsequent rehardening of the opaque polymer material joins the two pieces in a rigid and non-removable manner, thereby forming the laser weld joint 106 .

[0174] In the example shown, in particular, the step of forming the at least one laser weld joint 106 requires directing (one or more) laser beams r toward the outer surface 101e of the rear shell 101 so that the (one or more) laser beams r can penetrate into the opaque polymer material of the rear shell 101 and reach (one or more) internal components 104 at the relevant contact area 105.

[0175] The substantially conical shape of the incident laser beam r allows a relatively low energy density to be maintained on the outer surface 101e of the rear shell 101 and in the initial portion of the path of the laser beam r inside the rear shell 101 until the contact area 105, advantageously so that the laser beam does not melt or otherwise damage the opaque polymer material it has passed through.

[0176] Once reaching the corresponding internal component 104, each laser beam r locally heats the opaque polymer material of the internal lighting component 104 to a melting / softening temperature. At substantially the same time, the generated heat is also transferred to the opaque polymer material forming the rear housing 101 by conduction, causing the second polymer material to locally reach a melting temperature.

[0177] Reference Figure 6 , Figure 7 and Figure 8 Preferably, the step of forming the at least one laser welded joint 106 further provides that, when the (one or more) laser beams r heat the polymer material located near the contact area 105, the (one or more) internal components 104 to be welded are pressed against the inner surface of the rear shell 101 at the / each contact area 105.

[0178] Finally, the assembly of the automotive lighting unit 100 preferably further includes the step of welding the front half shell 102 to the mouth of the rear housing 101 after forming each laser welding joint 106. In other words, the assembly of the automotive lighting unit 100 preferably ends with the welding of the front half shell 102 to the mouth of the rear housing 101.

[0179] Obviously, the arrangement of the internal lighting component 104 inside the rear housing 101 and / or the welding of the internal lighting component 104 to the rear housing 101 may be performed according to a predetermined time sequence.

[0180] The operation of the assembly machine 1 for automotive lighting units can be easily inferred from the above description.

[0181] Reference Figure 5 After obtaining the rear shell 101 and (one or more) internal components 104, the assembly of the automotive lighting unit 100 preferably includes the following steps: placing the rear shell 101 into the receiving seat of the workpiece-carrying fixture 2, or more precisely placing it into the receiving compartment 5a of the workpiece-carrying template 5; and advantageously also includes the following steps: locking / fixing the rear shell 101 in the workpiece-carrying fixture 2, or more precisely locking / fixing it into the compartment 5a of the workpiece-carrying template 5.

[0182] After the rear shell 101 has been placed and advantageously also locked into the workpiece-carrying fixture 2, the assembly of the automotive lighting unit 100 preferably includes the following steps: placing (one or more) internal lighting components 104 inside the rear shell 101 fixed in the workpiece-carrying fixture 2, each internal lighting component 104 resting on the inner surface of the rear shell 101 in at least one corresponding contact section 105.

[0183] Reference Figure 7 and Figure 8After placing (one or more) interior lighting components 104 on the inner surface of the rear shell 101, the assembly of the automotive lighting unit 100 includes the following steps: starting the laser device 3 to guide one or more laser beams r toward (one or more) contact areas or sections 105 between the rear shell 101 and the one or more interior lighting components 104 present inside the rear shell 101, toward the outer surface 101e of the rear shell 101 fixed in the workpiece carrying fixture 2, so that (one or more) laser beams r pass through (one or more) internal laser paths of the workpiece carrying fixture 2.

[0184] In more detail, the assembly of the automotive lighting unit 100 requires guiding the laser beam r toward the outer surface 101e of the rear shell 101 via (one or more) internal through channels 7 of the workpiece-carrying template 5, so that the laser beam r can reach the outer surface 101e of the rear shell 101 with essentially no energy loss.

[0185] In addition, before starting the laser device 3, the assembly of the automotive lighting unit 100 preferably also includes the step of starting the locking assembly 4 to fix and / or press the (one or more) internal lighting components 104 to be welded onto the inner surface of the rear shell 101 contained in the workpiece carrying fixture 2.

[0186] In more detail, the assembly of the automotive lighting unit 100 preferably requires introducing the locking assembly 4, or more precisely the locking template 13, into the rear shell 101 housed in the workpiece carrying fixture 2, so that the (one or more) formed protrusions 13a of the locking assembly 4, or more precisely the locking template 13, can reach the (one or more) internal lighting components 104 and fix and / or press them on the inner surface of the same rear shell 101 at (one or more) contact areas or sections 105.

[0187] Reference Figure 1 , Figure 5 , Figure 6 and Figure 7 In the example shown, in particular, the assembly of the automotive lighting unit 100 preferably requires moving the workpiece-carrying template 5 of the workpiece-carrying fixture 2 in direction d so as to arrange the (one or more) forming protrusions 13a of the locking template 13 in abutment against the (one or more) internal components 104 to be welded above the (one or more) contact areas or sections 105, thereby fixing and / or locally pressing the internal components 104 to be welded onto the inner surface of the rear shell 101.

[0188] When the locking template 13 presses one or more internal components 104 to be welded onto the inner surface of the rear shell 101, the assembly of the automotive lighting unit 100 also requires temporarily starting the laser device 3, or more precisely, temporarily starting the laser source 10, so as to generate one or more laser beams r that continuously pass through the (one or more) internal laser paths of the workpiece carrying fixture 2 and the thickness of the rear shell 101 until reaching the (one or more) internal components 104.

[0189] After forming the various laser weld joints 106 , assembly of the automotive lighting unit 100 preferably requires removing the rear housing 101 and the interior lighting component(s) 104 rigidly integrated therewith from the workpiece carrying fixture 2 .

[0190] The advantages resulting from the use of the above-described assembly method and assembly machine 1 for automotive lighting units are considerable.

[0191] Fixing the interior lighting component 104 to the rear housing 101 by means of a laser welded joint 106 can eliminate all or in any case most of the self-tapping metal screws conventionally used to fix the interior lighting component to the rear housing of an automotive lighting unit, thereby significantly reducing the resulting weight and production costs.

[0192] In addition, laser welding performed with the aid of a laser beam r, wherein the laser beam r is essentially conical so as to be focused / concentrated in a focal point P located at the contact area 105 to which the laser beam r is directed, or alternatively spaced apart from the contact area 105 at the rear of the relevant contact area 105, resolves all operational limitations associated with the contact area 105 whose sides / boundaries are pieces or parts of pieces made of a polymer material that is opaque to visible light.

[0193] Furthermore, direct fixing of (one or more) internal components 104 by means of a laser welded joint 106 makes it possible to eliminate or at least greatly reduce the number of shoulders, centering pins and / or snap-on locking tabs typically present inside the rear housing of an automotive lighting unit, thereby significantly simplifying the structure of the mold used to produce the rear housing 101.

[0194] In fact, the creation of these centering and / or snap-locking systems leads to extremely complex shapes of the molds used to produce the rear housings of automotive lighting units assembled in a conventional manner.

[0195] Last but not least, the above-described machine 1 for assembling automotive lighting units makes it possible to simplify the assembly line of automotive lighting units, with all the advantages that this entails.

[0196] In fact, there is no need for automatic or semi-automatic screwdrivers anymore.

[0197] Finally, it is obvious that modifications and variations may be made to the method for assembling a vehicle lighting unit 100 and to the machine 1 for assembling a vehicle lighting unit, without departing from the scope of the present invention.

[0198] For example, in a first embodiment variant of the machine 1, the laser device 3 may include a series of independent laser sources, each of which emits a laser beam on command and is located in or aligned with a corresponding internal laser path of the workpiece-carrying fixture 2, or more precisely with an internal through channel 7 of the workpiece-carrying template 5, so as to guide its laser beam only into this internal laser path.

[0199] Obviously, in this embodiment, activation and deactivation of the individual laser sources may not occur simultaneously for all laser sources.

[0200] On the other hand, in a second embodiment variant of the machine 1, the laser device 3 may include a movable laser deflector instead of a beam of optical fiber 11, which is capable of deflecting the laser beam 106 generated by the laser source 10 as required on command and alternatively deflecting it towards the entrance of any internal laser path of the workpiece-carrying fixture 2 or more precisely towards the entrance of the internal through channel 7 of the workpiece-carrying template 5.

[0201] Thus, in this variant, the laser welded joints 106 may be formed one after the other, preferably in a given chronological order.

[0202] In a third embodiment variant of the machine 1, in addition, the laser device 3 can include a movable robotic arm instead of the bundle of optical fibers 11, which supports the laser source and is capable of aligning the laser source on command to any internal laser path of the workpiece-carrying fixture 2, or more precisely to any internal through channel 7 of the workpiece-carrying template 5, so as to continuously guide the laser beam r toward the respective contact areas 105 between the rear housing 101 and (one or more) internal lighting components 104.

[0203] Reference Fig. 9 In addition, in different embodiments, the laser device 3 is preferably configured to generate multiple separate and different laser beams r and direct them toward the workpiece carrying fixture 2 from different directions, so that at least a portion of these laser beams r cross / intersect inside the workpiece carrying fixture 2 at an intersection at a contact area 105 between the rear shell 101 and the internal lighting component 104, thereby forming at least one laser welding joint 106 at the contact area 105.

[0204] In other words, the assembly of the automotive lighting unit 100 preferably requires directing multiple laser beams r from different directions and within a predetermined time interval toward the same contact area 105 located inside the workpiece carrying fixture 2 so that the laser beams intersect at an intersection point substantially located at the contact area 105, thereby (only) melting the polymer material present in the vicinity of the contact area 105.

[0205] In more detail, at the intersection point, the energies delivered to the polymer material by the laser beams r are added to each other so as to heat (only) the opaque polymer material located near the contact area 105 to the melting / softening temperature of the polymer material.

[0206] Therefore, by having only an appropriate number of laser beams r intersecting at the contact area 105, the energy density can be kept at a relatively low value almost up to the contact area 105, which can be easily withstood by the opaque polymer material forming the rear half shell 101 without melting or suffering structural damage.

[0207] Obviously, the laser device 3 and the workpiece carrying fixture 2 are configured such that the laser beam r travels along the internal laser path or at least one internal laser path of the workpiece carrying fixture 2 to reach / impact the outer surface 101 e of the rear housing 101 .

[0208] The intersection point of the laser beam r is therefore located inside the workpiece carrier 2 outside the or an internal laser path of the workpiece carrier 2 .

[0209] Therefore, also in this case, the laser device 3 is constructed and coupled to the workpiece carrying jig 2 so that the laser beam r reaches the rear housing 101 fixed in the workpiece carrying jig 2 without passing through the mouth of the rear housing 101 .

[0210] In more detail, the laser device 3 is suitable for guiding at least two different laser beams r into the workpiece carrying fixture 2 from two different directions and through at least one internal laser path of the workpiece carrying fixture 2, so that the laser beams r reach the outer surface 101e of the rear shell 101 fixed in the workpiece carrying fixture 2, penetrate through the local thickness of the shell into the rear shell 101, and intersect / intersect at an intersection located inside the workpiece carrying fixture 2 at a contact area 105 between the rear shell 101 and the internal lighting component 104, thereby locally adding the power of the same laser beam r.

[0211] Obviously, the laser device 3 can also direct more than two laser beams r to the same intersection point.

[0212] Reference Fig. 9In the example shown, each internal laser path of the workpiece carrying fixture 2 is aligned with a respective contact area 105 and is preferably adapted to be traversed by a plurality of laser beams r directed towards the same contact area 105 from different directions.

[0213] Obviously, in different embodiments, several internal laser paths of the workpiece carrying fixture 2 may be aligned with the same contact area 105 , each of which may preferably be adapted to be traversed / passed by a single laser beam r directed towards the same contact area 105 .

[0214] In addition, the laser device 3 preferably comprises: at least one electrically powered laser source 10, which is capable of emitting a high-power laser beam on command, which laser beam advantageously has a predetermined, substantially constant intensity and / or emission spectrum; and a plurality of optical fibers 11, which terminate in the region of at least one internal laser path of the workpiece-carrying fixture 2 and are optically coupled to the laser source 10 in order to split the laser beam emitted by the laser source 10 and guide it to the at least one internal laser path.

[0215] Thus, the distal ends of the two or more optical fibers 11 are adapted to guide / direct their laser beams r into the workpiece carrying fixture 2 towards the same contact area or section 105 between the rear housing 101 and the internal lighting member 104 .

[0216] In addition, for each optical fiber 11, the laser device 3 preferably also includes a beam adjustment device 12, which is located downstream of the distal end of the optical fiber 11 so as to be passed through by the laser beam r coming out of the same optical fiber 11, and is constructed to collimate the laser beam r in a predetermined direction intersecting the intersection point and optionally also slightly focus, advantageously focusing it into the receiving seat portion of the workpiece carrying fixture 2, or more advantageously focusing it into the compartment 5a of the workpiece carrying template 5.

[0217] Therefore, two or more light beam adjusting devices 12 are aligned with the same contact area 105 between the rear housing 101 and the interior lighting member 104 .

[0218] In this variation, the step of forming the at least one laser weld joint 106 requires directing two or more separate and different laser beams r toward the contact area 105 from different directions and within a given time interval that is advantageously less than 30 s (seconds), so that the multiple laser beams r cross / intersect at an intersection at the contact area 105 between the rear shell 101 and the internal component 104, thereby locally adding their powers and heating (only) the opaque polymer material located near the contact area 105 to a melting / softening temperature.

[0219] Finally, in a more complex embodiment of the machine 1 not shown, even the locking assembly 4 or more precisely the locking template 13 can be provided with one or more internal laser paths enabling one or more laser beams to reach the internal lighting component 104 in an area or section 105 where the internal lighting component 104 rests on the rear housing 101.

[0220] Furthermore, in this more complex embodiment, the machine 1 is advantageously also provided with a second laser device, which is coupled to the locking assembly 4, or more precisely to the locking template 13, so as to guide its (one or more) laser beams through one or more internal laser paths of the locking assembly 4 to the interior of the rear housing 101.

Claims

1. A method for assembling an automobile lighting unit (100), the automobile lighting unit (100) comprising: A concave rear shell (101) having a substantially rigid and opaque structure and adapted to be fixed to a vehicle body; a front half shell (102) having a substantially rigid and transparent structure and arranged to close the mouth of the rear shell (101); at least one lighting assembly (103) located within the rear shell (101) and adapted to backlight a corresponding transparent or translucent sector of the front half shell (102); and one or more internal lighting components (104) fixed in abutment to the inner surface of the rear shell (101) at corresponding contact areas or sections (105); The assembly method is characterized in that it comprises the following steps: Obtaining the rear housing (101); obtaining at least one internal lighting member (104) having at least one portion made of an opaque polymer material; placing the at least one internal lighting member (104) inside the rear housing (101) such that the portion made of the opaque polymer material rests on the rear housing (101) in at least one contact section (105); At least one laser weld joint (106) is formed at the contact area (105) to rigidly secure the at least one interior lighting component (104) to the rear housing (101).

2. A method for assembling an automotive lighting unit according to claim 1, wherein the step of forming the at least one laser weld joint (106) requires directing one or more laser beams (r) through the thickness of the rear shell (101) towards the contact area (105) so as to reach and heat the polymer material located near the contact area (105) until the melting / softening temperature.

3. The assembly method of an automotive lighting unit according to claim 2, wherein the step of forming the at least one laser weld joint (106) requires directing a laser beam (r) toward the contact area (105) within a predetermined time interval, concentrating the laser beam (r) in a focal point (P) located at the contact area (105) or behind the contact area (105) at a predetermined distance (d) from the contact area (105) so as to melt the polymer material present near the contact area (105).

4. The method for assembling an automotive lighting unit according to claim 2, wherein the step of forming the at least one laser weld joint (106) requires directing a plurality of laser beams (r) toward the contact area (105) from different directions and within a predetermined time interval so that the laser beams (r) intersect at an intersection point substantially located at the contact area (105), thereby melting the polymer material present near the contact area (105).

5. A method for assembling an automotive lighting unit according to claim 2, 3 or 4, wherein the step of forming the at least one laser weld joint (106) further comprises the step of pressing the at least one interior lighting component (104) against the inner surface of the rear housing (101) at the contact area (105) when one or more of the laser beams (r) heat the polymer material.

6. A method for assembling an automotive lighting unit according to claim 2, 3, 4 or 5, wherein the step of forming the at least one laser weld joint (106) also includes the step of fixing the at least one internal lighting component (104) inside the rear shell (101) when one or more of the laser beams (r) heat the polymer material.

7. An assembly method for an automotive lighting unit according to any one of the preceding claims, wherein before the step of forming the at least one laser welding joint (106), the method includes the step of placing the rear shell (101) onto a workpiece carrying fixture (2), the workpiece carrying fixture (2) being provided with a receiving seat (5a) suitable for accommodating the rear shell (101) and one or more internal laser paths (7), wherein each internal laser path (7) is constructed to allow one or more of the laser beams (r) to pass through the workpiece carrying fixture (2) substantially without energy loss until reaching the rear shell (101) accommodated in the workpiece carrying fixture (2).

8. The method for assembling an automobile lighting unit according to claim 7, characterized in that: The method also includes the step of locking / fixing the rear housing (101) in the receiving seat (5a) of the workpiece carrying fixture (2).

9. Method for assembling an automotive lighting unit according to any of the dependent claims, wherein at least a portion of the interior lighting components (104) together form the at least one lighting assembly (103).

10. An assembly machine (1) for an automobile lighting unit, comprising: a workpiece A carrier fixture (2), the workpiece carrier fixture (2) being provided with a receiving seat (5a) suitable for accommodating a rear housing (101) of the automotive lighting unit (100) to be assembled, the rear housing (101) internally having one or more internal components (104) resting on the inner surface of the rear housing (101) at one or more contact areas (105); and a laser device (3), the laser device (3) being suitable for generating at least one laser beam (r) and directing the at least one laser beam (r) towards the rear housing (101) accommodated in the workpiece carrier fixture (2); The assembly machine (1) for the automotive lighting unit is characterized in that the laser device (3) is suitable for guiding the at least one laser beam (r) toward the workpiece carrying fixture (2) in a direction intersecting with at least one contact area (105) between the rear shell (101) and the interior lighting component (104) so ​​as to form at least one laser welding joint (106) at the contact area (105); the workpiece carrying fixture (2) and the laser device (3) are constructed so that the at least one laser beam (r) passes through the thickness of the rear shell (101) accommodated in the workpiece carrying fixture (2) to reach the contact area (105).

11. An assembly machine for an automotive lighting unit according to claim 10, wherein the workpiece carrying fixture (2) is provided with at least one internal laser path (7), the at least one internal laser path (7) extending through the workpiece carrying fixture (2) until the receiving seat portion (5a), being substantially aligned with the contact area (105), and being constructed to allow the laser beam (r) to pass through the workpiece carrying fixture (2) to reach the receiving seat portion (5a); the laser device (3) is coupled to the workpiece carrying fixture (2) so that the at least one laser beam (r) travels along the at least one internal laser path (7) to reach the receiving seat portion (5a) of the workpiece carrying fixture (2).

12. An assembly machine for an automotive lighting unit according to claim 11, wherein the workpiece-carrying fixture (2) comprises a workpiece-carrying template (5) having a substantially non-deformable structure; the receiving seat (5a) and the at least one internal laser path (7) are arranged in the workpiece-carrying template (5).

13. The assembly machine for automobile lighting units according to claim 12, wherein the shape of the receiving seat (5a) in the workpiece-carrying template (5) is substantially complementary to the shape of the rear housing (101).

14. An assembly machine for an automotive lighting unit according to claim 12 or 13, wherein the workpiece-carrying fixture (2) further comprises a locking device, which is suitable for selectively locking / fixing the rear shell (101) in the receiving seat (5a) of the workpiece-carrying template (5).

15. Assembly machine for automotive lighting units according to claim 12, 13 or 14, wherein the internal laser path (7) comprises a through hole, an opening or a straight duct provided in the body of the workpiece-carrying template (5).

16. The vehicle lighting unit assembly machine according to any one of claims 10 to 15, characterized in that: The invention also comprises a locking assembly (4), which is capable of moving away from and toward the workpiece carrying fixture (2), or vice versa, and is suitable for fixing and / or pressing one or more internal lighting components (104) present in the rear shell (101) onto the inner surface of the rear shell (101) accommodated in the workpiece carrying fixture (2).

17. An assembly machine for an automotive lighting unit according to claim 16, wherein the receiving seat portion (5a) of the workpiece-carrying template (5) is provided with an inlet and outlet, and the rear shell (101) is inserted into and removed from the workpiece-carrying template (5) through the inlet and outlet; the locking assembly (4) is arranged in front of the mouth of the receiving seat portion (5a) of the workpiece-carrying template (5), and is capable of moving away from and toward the receiving seat portion (5a) in a substantially straight line, or vice versa.

18. An assembly machine for an automobile lighting unit according to claim 16 or 17, wherein the locking assembly (4) includes a locking template (13), and the locking template (13) is provided with one or more forming protrusions (13a), wherein each forming protrusion (13a) is formed to enter into the interior of the rear shell (101) through the mouth of the rear shell (101) accommodated in the workpiece carrying fixture (2) to fix and / or press the corresponding internal lighting component (104) against the inner surface of the rear shell (101).

19. An assembly machine for an automotive lighting unit according to any one of claims 11 to 18, wherein the laser device (3) is suitable for focusing / concentrating the laser beam (r) in a focal point (P), which is located outside the internal laser path (7), spaced apart from the contact area (105) at the rear of the contact area (105) within the workpiece carrying fixture (2) or at the contact area (105).

20. An assembly machine for an automotive lighting unit according to any one of claims 11 to 18, wherein the laser device (3) is suitable for directing a plurality of laser beams (r) from different directions toward the workpiece carrying fixture (2) so that the laser beams intersect at at least one intersection point, the at least one intersection point being located outside the internal laser path (7) at the contact area (105) inside the workpiece carrying fixture (2).

21. The assembly machine for automotive lighting units according to any one of claims 11 to 20, wherein the laser device (3) comprises: at least one electric laser source (10) capable of emitting a laser beam on command; and one or more optical fibers (11), each of which terminates at the at least one internal laser path (7) of the workpiece carrying fixture (2) and is optically coupled to the laser source (10) to direct the laser beam to the internal laser path (7).

22. An automotive lighting unit (100), comprising: A rear housing (101) having a concave shape and adapted to be fixed to a vehicle body; a front half-shell (102) arranged to close the mouth of the rear housing (101) and provided with at least one transparent or translucent sector; and at least one lighting assembly (103) located inside the rear housing (101) and adapted to backlight the front half-shell (102); The automotive lighting unit (100) is provided with at least one inner component (104) which is at least partially made of a polymer material and rests on the inner surface of the rear housing (101) in at least one contact area (105); The automotive lighting unit (100) is characterized in that the rear housing (101) and the at least one internal component (104) at the contact area (105) are both made of an opaque polymer material, and the rear housing (101) and the at least one internal component (104) are rigidly fixed to each other by means of a laser welded joint (106) formed at the contact area (105).

23. The automotive lighting unit according to claim 22, wherein the laser welded joint (106) is substantially point-shaped or has a line shape.

24. The automotive lighting unit according to claim 22 or 23, wherein the rear housing (101) and the at least one internal component (104) at the contact area (105) are made of opaque polymer materials having laser beam absorption coefficients (μ) different from each other.

25. The automotive lighting unit of claim 24, wherein the difference between the laser beam absorption coefficients (μ) of the two opaque polymer materials is greater than 35% of the laser beam absorption coefficient (μ) having the larger value.

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