DE102005004806B3 - Coupling device for connecting light emitter or light receptor with fiber optic cable has light-conducting coupling elements formed by in a channel interposed pieces of optical fiber wherein first retainer is provided at coupling device - Google Patents

Abstract

Coupling device (100) has first and second interface whereby multitude of light-conducting coupling element (102) interconnects them. The light-conducting coupling elements are formed by in a channel (104) interposed pieces of optical fiber. A first retainer is provided at coupling device for light emitter and/or light receptor to connect the pieces of optical fiber with the light emitter and/or light receptor. Independent claims are also included for the following: (A) Measuring transformer unit; and (B) Procedure for manufacturing coupling device.

Description

The The present invention relates to a coupling device for connecting at least one light transmitter and / or light receiver with at least one optical fiber. Furthermore, the present invention relates Invention on a transducer unit for receiving and / or transmitting Light radiation from and / or to an optical waveguide, wherein the Transducer unit a coupling device and at least one Transmitter and / or light receiver includes. The present invention finally relates to a manufacturing method for producing such a coupling device and for manufacturing a transducer unit.

to fulfillment the requirements of the framework directive of European car manufacturers for pedestrian protection can both active and passive protective measures are used. It must for the Bumper, that Front end and especially the bonnet constructive solutions found be the one for a pedestrian impact necessary Deformation path and the corresponding compliance of the vehicle structure to accomplish. A common case The examined protection concept relies on setting up the bonnet before the pedestrian hits the vehicle, so the necessary energy absorption capacity in this area provide. Such an active protection system needed in addition the actuator, which does the putting up of the hood, too a suitable sensor for detecting and classifying the collision object.

In In this context, fiber optic sensor systems for the control were the actuator developed on a fiber optic fiber optic based integrated into the bumper and its light-guiding properties are influenced by a deformation become. Such sensor strips consist of a number of plastic optical fiber loops, in which light is conducted from the transmitter to the receiver. At a bend of the optical waveguide, a part of the light output is coupled out. At rest, the transmitted Light output constant; at a z. B. caused by an impact Bend changes these. The loss rate depends thus directly from the direction of the bending of the fiber and the amount of loss rate is proportional to the strength the bend.

Around to be able to detect a bending of the optical waveguide band has such a fiber optic contact sensor comprises a transducer unit, the light radiation couples into the light wave band and the emergent one Detected light radiation and supplies a further evaluation.

Known is, for. For example to use the dashboard lighting in motor vehicles the light too over transport geometrically complex structures. These for lighting However, in the visible range imaginary molded parts are only for applications suitable in which the transmitted Light output is not relevant to function.

Farther are so-called mini or micro-pigtails, for example, to bridge the Area between harness connector and diodes known. Designate Pigtails optical fiber pieces, which at one end with a connection for a light emitter and / or light receiver are provided and the other end with an optical contact connected is.

There however for the application in a fiber optic sensor system the light intensity with both defined characteristics are coupled as well as read out must, the coupling between the light emitters or light receivers and the Fiber optic cables are of particular importance. As continue to be both for the fiber optic band as well as for the light transmitters and receivers resorted to prefabricated parts should be, there is a need coupling possibilities to create an adaptation between each geometric Allow grids.

From the European patent application EP 0 566 900 A1 is a coupling device for connecting optical fibers with optical fibers, which are integrated in a printed circuit substrate, known, are provided in the molded in a base body optical waveguide, wherein the main body of the coupling device can be inserted into a receptacle of the circuit substrate.

From the publication DE 30 26 631 C2 is a transition piece for transferring a circular wire arrangement of a multi-core optical fiber cable into a linear wire arrangement known in which a molding with spatially curved channels ensures that the wires are implemented in their grid during insertion into the molding and through the channels.

The publication DE 25 22 740 B2 discloses an apparatus for connecting an incoming fiber optic cable to a continuity cable. In this case, the optical fibers to be connected of the incoming and continuing cables are inserted into the connector and either coupled directly to each other end face or optically mitein an intermediate lens assembly connected.

The Task underlying the present invention consists therein, a coupling device for connecting at least one Light emitter and / or light receiver specify with at least one optical waveguide, the op coupling properties has and with high flexibility the lowest possible assembly costs needed.

These The object is solved by the subject matter of the independent patent claims. advantageous Further developments of the present invention are the subject of the dependent claims.

The The present invention is based on the idea that optimal optical Coupling between the light transmitter / receiver and the optical fiber can be achieved if the coupling device has a first interface, which can be connected to the at least one light transmitter and / or light receiver is, and a second interface, which with a variety of terminals of the Optical waveguide is connectable, and has a plurality of photoconductive coupling elements, the first and the second interface connects with each other. With such an arrangement may also in Use of prefabricated components on particularly simple Way an adaptation of different grid dimensions of the optical axes to the Both interfaces are made.

If the coupling device has a photoconductive coupling element, that in a guide channel the coupling device is held, the optical coupling between the light transmitter / receiver and the optical waveguide are further improved. Leading the Coupling element allows exact positioning on both interfaces, d. H. both to the light transmitter / receiver as well as the optical fiber and an optimal adaptation of different grid dimensions to the both interfaces.

forms one the guide channel so that the coupling element assumes a curved shape, so can advantageously an adaptation to any different Geometries can be achieved at the two interfaces.

used one as a coupling element, an optical waveguide piece, preferably made of plastic or Quartz glass, so this solution offers the advantage that in a very cost effective way a particularly good optical quality the coupling can be achieved. In particular, the use of so-called plastic This is made possible by optical fibers (POF), ie plastic fiber optic cables Introduce of the optical fiber piece in the guide channel, without running the risk that the coupling element breaks.

According to one advantageous development of the present invention, the Coupling device a base body, in which the at least a guide channel is formed, and a separate housing, which at least a coupling element to the outside essentially completes on. In this way, in manufacturing technology particularly easy realizable manner a substantially closed arrangement be achieved. The enclosure can do this for the necessary Light-tightness to prevent interference. Especially, if the main body produced in an injection molding process where the restriction exists that undercuts can not be demoulded, offers the divisions in the main body and a separate enclosure the possibility, also form completely closed guide channels.

Around a secure stop for the light emitter and / or the light receiver on the coupling device to ensure, a first receptacle may be provided in which the light emitter and / or -receiver taken and in a defined position opposite one first interface of the coupling element is held. For the connection with the optical waveguide with the second interface of the coupling element may be provided a second shot. Alternatively, the coupling device also so executed be that they by pressing on corresponding input and output surfaces the optical waveguide produces the optical coupling.

The inventive principles are used particularly advantageously in a transducer unit, in which the required light emitter and / or light receiver included so that this transducer unit is considered a completely assembled module for the Optoelectronic interface between an optical waveguide and the vehicle electronics can be used. additional Signal processing electronics may optionally have some intelligence provide the transducer unit, for example, the coupling to facilitate data bus systems.

The inventive method for producing such a coupling device essentially comprises the steps of producing a base body, in which at least one guide channel for receiving at least one optical coupling element is formed, and arranging this optical coupling element in the guide channel. This procedure can be a well-defined positioning of the two Interfaces of the optical coupling element can be ensured in a particularly simple manner.

Especially by arranging the optical coupling element in such a way that it's a curved one Form adopts the adaptation to a variety of grid geometries be achieved.

Especially simply the assembly of the coupling element, if it is designed this coupling element is an optical waveguide piece, that in the guide channel inserted substantially in the direction of the longitudinal axis of the optical waveguide piece becomes.

Around the necessary Protection to the outside, especially against stray light, to achieve, can continue to surrounding housing to be assembled. This can be done in a particularly efficient way Sliding a substantially sleeve-shaped housing structure substantially in the direction of the longitudinal axis take place of the coupling element.

In order to the coupling element is fixed immovably in the guide channel and in particular its position relative to the light transmitting / receiving units no longer changeable is, it may preferably be fixed by a welding point.

A particularly good optical coupling between the at least one light transmitter and / or light receiver with the coupling element can be achieved when the light emitter and / or light receiver For example, a diode by pushing into one of the coupling device provided receptacle is mounted. It allows insertion into a Direction substantially transverse to the longitudinal axis of the coupling element a particularly secure hold.

Based the embodiments shown in the accompanying drawings the invention will be explained in more detail below. Similar or corresponding Details are provided in the figures with the same reference numerals. Show it:

1 a side view of a transducer unit according to an advantageous embodiment;

2 a rotated by 90 ° side view of the transducer unit 1 ;

3 a perspective view of a basic body of the coupling device according to the invention;

4 a side view of the body 3 ;

5 a top view of the main body of the 3 ;

6 a side view of the body 3 ;

7 another side view of the main body 3 ;

8th another side view of the main body 3 ;

9 a bottom view of the main body of the 3 ;

10 a perspective view of a Umgehäuses;

11 a plan view of the housing of the 10 ;

12 a side view of the enclosure 10 ;

13 another side view of the enclosure 10 ;

14 a bottom view of the housing of the 10 ;

15 another side view of the enclosure 10 ;

16 another side view of the enclosure 10 ;

17 a cross section through an optical fiber acting as a photoconductive coupling element;

18 a side view of the optical fiber;

19 a perspective view of a cover for the first recording;

20 a side view of the cover 19 ;

21 another side view of the cover 19 ;

22 another side view of the cover 19 ;

23 another side view of the cover 19 ;

24 another side view of the Abde off 19 ;

25 another side view of the cover 19 ;

26 a side view of a first form of a diode;

27 a rotated by 90 ° view of the diode 26 ;

28 a second type of diode for installation in the coupling device according to the invention;

29 a rotated by 90 ° view of the diode 28 ,

1 shows an advantageous embodiment of a transducer unit 144 with a coupling device 100 for connecting light emitting / receiving diodes with at least one optical waveguide, not shown here. In the in 1 As shown, the coupling surface is shown on the optical waveguide. According to the invention are in the coupling device 100 photoconductive coupling elements 102 arranged, which can be connected to corresponding coupling surfaces on an optical waveguide and irradiate light output as well as can receive light radiation. In the embodiment shown, the coupling elements become 102 formed by short pieces of optical waveguide, which are preferably made of so-called plastic optical fibers, so plastic optical waveguides. As is clear from the following figures, the use of plastic optical fibers has 102 the advantage of higher stability and elasticity. Of course, it is also possible to use optical fibers made of quartz glass or of any other materials. The coupling elements 102 are according to the invention in guide channels 104 held and connected at the other end with diodes whose terminals 106 in the 1 are recognizable.

The coupling device 100 has a basic body 108 on, in which trenches for the guide channels 104 are created, and a separate from the body surrounding housing 110 that the pieces of optical fiber 102 with the exception of the provided for contact with the optical waveguide band end faces outwards. The enclosure 110 serves to secure the optical waveguide pieces 102 and for their attachment to the body 108 , as for the production of curved guide channels 104 for manufacturing reasons, the half-side opening is required.

In the embodiment shown, the coupling device 100 also mounting brackets, so-called board locks 112 on, which allow an efficient connection to a circuit board.

The pieces of optical fiber 102 can also work with the main body 108 and the enclosure 110 be welded.

2 shows the coupling device 100 in a opposite to the presentation 1 rotated by 90 ° view. As can be seen from this illustration, the surrounding housing 110 a substantially sleeve-shaped shape and is over the body 108 in one direction 114 pushed before the pieces of optical fiber 102 to be assembled. The diodes are after their assembly by a cover 116 in the direction 118 can be postponed, protected from external influences. The front side 120 designates the areas intended for coupling to the optical waveguide strip.

3 shows in a perspective view of the main body 108 according to an advantageous embodiment. According to the invention, the main body connects 108 a recording 122 in which the diodes, not shown here, are held, with an intended for coupling to an optical waveguide end face 120 via guide channels 104 , in which the in the 1 and 2 represented optical fiber pieces 102 can be introduced. According to an advantageous embodiment of the basic body 108 manufactured as an injection molded part. Since undercuts in an injection molded part are not demoldable, according to the invention on the body 108 only a substantially U-shaped channel for forming a first part of the guide channels 104 formed. The complete guide channel forms as out 1 can be seen, through the interaction with the surrounding housing 110 ,

How out 3 recognizable, have the guide channels 104 a curved shape, so that the inserted optical fiber pieces 102 assume a curved shape and mediate in this way between the different grids of the diodes and the input / output surfaces of the optical waveguide band.

locking lugs 124 act with corresponding detent openings on the surrounding housing 110 together so that the enclosure 110 on the body 108 is pre-fixed. holders 126 are molded on the sides to mount the board locks 112 to enable.

Different side views of the main body 108 are in the 4 to 9 shown. In this case, the embodiment shown is designed for connecting a total of four diodes, each with a transmitting and receiving element. Corresponding eight guide channels 104 trained by the recording 122 for the diodes in a curved shape to the face 120 , which is coupled to the fiber optic band lead.

To the guide channels 104 completely close and at the same time the pieces of optical fiber 102 to protect against interference from the outside, according to the invention on the body 108 a surrounding housing 110 pushed that into the 10 to 16 shown in detail. The inner contour of the surrounding housing 110 is the outer contour of the main body 108 in the area of the guide channels 104 essentially adjusted. This indicates the surrounding housing 110 a substantially sleeve-shaped structure, here with a rectangular cross section, on. latching openings 128 are intended to with the locking lugs 124 at the base body 108 for fixing the housing 110 co. openings 130 allow the connection with the mating connector of the fiber optic band (not shown here).

A schematic representation of an optical fiber piece 102 is in the 17 and 18 shown. In the embodiment shown, it is a plastic optical fiber, a so-called plastic optical fiber (POF) with a core 132 ("Core"), a coat 134 ("Cladding") and an outer coating ("coating") not shown here. The length L of the optical waveguide pieces 102 can be determined by gän giger method for cutting optical fibers with the required accuracy. For example, in the example shown, L may assume values in the range of 15 to 30 mm. Of course, other lengths are also possible depending on the particular requirements.

19 shows a perspective view of an embodiment of a lid 116 to close the recording 122 after the diodes are mounted. Springy bends 136 fix the diodes in their mounted position.

The 20 to 25 show some detail views of the lid 116 out 19 ,

In the 26 to 29 are the diodes 138 shown in the coupling device according to the invention 100 to be assembled. In the embodiment shown, each diode 138 a transmitting and a receiving element 140 . 142 on. According to their position in the recording 122 become the diodes with longer or shorter connections 106 according to the 26 and 27 or 28 and 29 Mistake.

If the diodes 138 at the coupling device 100 are mounted, so it is a transducer unit 144 formed, which is used as a compact unit for generating and reading the signals by an optical waveguide sensor belt, for example in the field of pedestrian protection. The transducer unit 144 thus connects the optical waveguide sensor belt with the required light emitters (eg LEDs) and light receivers (photodiodes). The transducer unit 144 is designed for mounting on a printed circuit board (not shown here).

The following is intended with reference to the 1 to 29 the installation of a complete transformer unit 144 be summarized.

First, separate main body 108 and a surrounding housing 110 produced. On the body are curved guide channels 104 formed, the inclusion of optical fiber pieces 102 serve. Since closed, curved channels can not be demoulded by injection molding technology, these are each only U-shaped and open at the top. The open side is housed respectively by the order 110 closed, which by sliding in the direction 114 is mounted. The main body 108 and the enclosure 110 together form a variety of curved channels 104 into which the previously cut to length pieces of optical fiber 102 be introduced.

The optical fiber parts 102 be by pushing into the curved guide channel 104 forced from their original straight shape into a curved shape and are characterized by their rigidity in the guide channels 104 prefixed. Subsequently, the optical waveguide pieces 102 depending on the requirements of each application in a further way, for. B. by a weld or another cover, finally fixed. For this purpose, the enclosure is 110 preferably made of a transparent plastic for the welding laser. Conceivable are other compounds, eg. B. by material bond, positive connection or adhesion (gluing).

The board locks can then be used for mounting on a printed circuit board 112 be attached.

The diodes 138 be by pushing in direction 115 in the recording 122 secured. In this position, the diodes are at a precisely defined distance to the cut surfaces of the optical waveguide pieces 102 , To the diodes 138 In the next work step, a cover can be permanently fixed and protected against adverse effects from the outside 116 to be assembled. The finished transducer unit 144 can now be mounted on a circuit board and the connections 106 the diodes are connected, for example via a soldering process with corresponding leads. Of the cover 116 can be optimally fixed by means of a laser welding process.

Although in the previous figures, eight guide channels for connecting four transmitting and four receiving units were always shown with the input and output of a total of four sensitive optical waveguides, it is clear that the coupling device according to the invention 100 is applicable for any number of light emitting / receiving units.

Claims (16)

Coupling device for connecting at least one light emitter and / or light receiver ( 138 ) with at least one optical waveguide, wherein the coupling device ( 100 ) a first interface with the at least one light emitter and / or light receiver ( 138 ), and a second interface, which is connectable to a plurality of terminals of the optical waveguide, has, and wherein a plurality of photoconductive coupling elements ( 102 ) connects the first and the second interface with each other, characterized in that the photoconductive coupling elements pass through into a guide channel ( 104 ) inserted optical fiber pieces are formed and that at the coupling device ( 100 ) at least one first recording ( 122 ) for the light emitter and / or light receiver ( 138 ) for connecting the optical fiber pieces ( 102 ) with the light transmitter and / or light receiver ( 138 ) is provided. Coupling device according to claim 1, wherein the optical fiber pieces ( 102 ) are made of plastic or quartz glass. A coupling device according to claim 1 or 2, wherein the optical axes of the photoconductive coupling elements ( 102 ) at the first interface have a different distance from each other than the optical axes of the photoconductive coupling elements ( 102 ) at the second interface. Coupling device according to at least one of the preceding claims, wherein the guide channel ( 104 ) is formed so that the coupling element ( 102 ) assumes a curved shape. Coupling device according to at least one of the preceding claims, wherein the coupling device ( 100 ) a basic body ( 108 ), in which the guide channels ( 104 ) are formed, and a separate housing ( 110 ), which the coupling elements ( 102 ) at least partially closes to the outside, has. Coupling device according to at least one of the preceding claims, wherein on the coupling device ( 100 ) at least one second receptacle for the optical waveguide for connecting the coupling element ( 102 ) is provided with the optical waveguide. Transducer unit for receiving and / or transmitting light radiation from and / or to an optical waveguide, wherein the transducer unit ( 144 ) comprises the following components: at least one light transmitter and / or light receiver ( 138 ), one with the light emitter and / or light receiver ( 138 ) connected coupling device ( 100 ) according to at least one of claims 1 to 6. Method for producing a coupling device for connecting at least one light transmitter and / or light receiver with at least one optical fiber, the method being the following Steps: Producing a base body in which at least one guide channel designed to receive at least one optical coupling element is; Arranging the optical coupling element in the guide channel by inserting a piece of optical fiber into the guide channel in the direction of the longitudinal axis of the optical fiber piece. The method of claim 8, wherein the coupling element so in the guide channel is arranged to take a curved shape. Method according to one of claims 8 or 9, further comprising the following step: Mount a cover to order the coupling element to the outside at least partially complete. The method of claim 10, wherein said mounting of the enclosure the sliding of a sleeve-shaped housing in Direction of the longitudinal axis of the coupling element. The method of claim 10, wherein said mounting of the enclosure includes placing a lid. Method according to one of claims 8 to 12, wherein the coupling element in the guide channel through a spot weld is fixed. A method of manufacturing a transducer unit having a coupling device made according to any one of claims 8 to 13, further comprising the step of: mounting at least one light emitter and / or light receiver by insertion into a receptacle on the coupling device such that the min at least one light transmitter and / or light receiver is optically connected to an associated coupling element. The method of claim 14, wherein the at least a light emitter and / or light receiver in one direction across to the longitudinal axis of the light coupling element is inserted. The method of claim 14, wherein the at least a light emitter and / or light receiver in the direction of the longitudinal axis of the light coupling element is inserted.