WO2021007850A1

WO2021007850A1 - Adapter unit for an electrical component and assembly method

Info

Publication number: WO2021007850A1
Application number: PCT/CN2019/096525
Authority: WO
Inventors: Dhanesh M K; Thomas Klenner; Pai Rajendra
Original assignee: Te Connectivity India Private Limited; Te Connectivity Germany Gmbh; Tyco Electronics (Shanghai) Co., Ltd.
Priority date: 2019-07-18
Filing date: 2019-07-18
Publication date: 2021-01-21

Abstract

An adapter unit for an electrical component and a corresponding method of assembling the adapter unit for the electrical component. The adapter unit (100) comprises at least one first connector element (102), at least one second connector element (104), wherein the first connector element (102) differs in size and/or position from the size and/or position of the second connector element(104), and at least one electrically conductive interconnection element (106) electrically interconnecting the first connector element (102) with the second connector element(104), wherein the interconnection element(106) comprises a lead frame assembly (108), wherein the lead frame assembly (108) comprises at least one interconnection contact (110) having at least two redundant contact portions (110', 110" ) arranged at different positions, and wherein the second connector element (104) comprises a separately formed contact assembly which is attached to only one of the redundant contact portions (110', 110" )for defining the position of the second connector element (104).

Description

Adapter unit for an electrical component and assembly method

The present invention relates to an adapter unit for an electrical component and to a corresponding method of assembling an adapter unit for an electrical component.

For electrically connecting electrical and electronic component such as relays and thermostats to signal and power lines, an adapter unit, which often is also referred to as a platform module is usually necessary to connect the electrical component to a standardized connector interface.

For instance, in the field of household appliances, but also in the field of heating or for automotive applications, the so-called RAST connectors are widely used. During the last decades, RAST has become the industry standard in home appliance wiring-harnesses. In codifying their RAST standards, European manufacturers created two basic categories. The first, PAST 2.5, refers to multiple-wire connectors with a 2.5-millimeter pitch, or spacing. This category is used primarily for Iow-power control circuits. The second, PAST 5, defines the parameters for connectors with a 5-millimeter pitch. In practice, this type is used primarily for higher-amp power circuits. At its most basic, a PAST connection is comprised of a header receptacle mounted on e.g. a motor housing or a controller PCB, and a block connector terminating anywhere from one to a couple of dozen wires. Although the wire termination portion of each connector model varies depending on the manufacturer, the plug side, or connector face for all PAST connectors is standardized. The platform module translates the standardized PAST interface into a set of terminals that contact the terminals arranged at the electrical/electronic component.

Conventionally, electrical components with the same functionality, but manufactured by different suppliers, often have a different arrangement of their electrical terminals, also called foot print. Consequently, conventional platform modules have to be fabricated with a variety of different foot prints in order to accommodate for electrical components from different suppliers. Thereby, however, the costs are enhanced and a fast change of supplier is often impossible. Furthermore, different tolerances of the position of the electrical terminals may also limit the interchangeability of the electrical components to be used with a conventional platform module.

There is still a need for an improved adapter unit and assembly method that can be used with a large variety of electrical components having different foot prints and/or terminal position tolerances for the same functionality, thereby overcoming, or at least substantially reducing the above mentioned problems and drawbacks.

This object is solved by the subject matter of the independent claims. Advantageous embodiments of the present invention are the subject matter of the dependent claims.

The present invention is based on the idea of providing a lead frame with redundant interconnection contacts that can be selectively connected to lead-out contact elements, so that the chosen position of the lead-out contact elements defines the foot print of the adapter unit. It could for instance be shown that with such a design around 60 %of all thermostats available on the market can be contacted with one common platform module. Hence, the fabrication costs for household appliances using such thermostats can be reduced significantly. It is of course clear that such an adapter unit can also be advantageously used with any other electrical/electronic devices that have varying foot prints of their terminals.

In particular, the present invention provides an adapter unit comprising at least one first connector element, at least one second connector element, wherein the first connector element differs in size and/or position from the size and/or position of the second connector element, and at least one electrically conductive interconnection element electrically interconnecting the first connector element with the second connector element, wherein the interconnection element comprises a lead frame assembly. The lead frame assembly comprises at least one interconnection contact having at least two redundant contact portions arranged at different positions, wherein the second connector element comprises a separately formed contact assembly which is attached to only one of the redundant contact portions for defining the position of the second connector element.

Usually, it is sufficient to provide two second interconnection contact portions of which only one is contacted by the second connector element forming a lead-out contact element. However, if necessary, also a larger number of redundant interconnection contact portions can be provided in order to meet with a larger range of different foot prints. In this case, more than one interconnection contact portion remains unused during operation of the electrical component. Furthermore, it has to be noted that such a redundancy may be provided at both sides of the adapter unit. In other words, also the first interconnection contact may additionally or alternatively be provided with redundant contact portions that can selectively be connected to separately formed contact assemblies.

According to an advantageous aspect of the present invention, the first connector element may comprise a header housing interface and a plurality of first tabs connected to the header housing interface. In particular, the header housing interface may be compatible with the above mentioned PAST standard, allowing a broad field of applications for the adapter unit according to the present invention.

According to an advantageous aspect of the present invention, the adapter unit may comprise a cover element which provides at least one opening for accessing the at least on second connector element from outside the adapter, wherein the position of the opening defines the position of the second connector element. Advantageously, such a cover element easily codes the required foot print of the second connector elements, which is presented to a particular electrical and/or electronic component. This facilitates the assembly process and reduces manufacturing costs.

The second connector elements can be mounted on the interconnection contacts in a particularly efficient manner, if the contact assembly comprises a double fork contact arranged in an electrically insulating contact assembly housing. The mounting of the second connector elements may thus be performed by an automated pick-and-place process.

According to an advantageous aspect of the present invention, the second interconnection contact comprises an elongated electrically conductive rail element, wherein the position of the contact assembly is variable along the rail element, and/or the second interconnection contact comprises at least two elongated electrically conductive rail elements and the position of the contact assembly is determined by the position of the contact assembly on one of the rail elements. A particularly high degree of freedom can be provided, if the position of the contact assembly is variable along the rail element, because in this manner, a continuous (i.e. stepless) change of position is possible for the second connector elements, so that even small position variations due to fabrication tolerances of the electrical and/or electronic component can be compensated.

In order to safely secure the second connector element at the adapter unit, the rail element may have locking means for fixing the contact assembly in a chosen position along the rail element.

A particularly efficient manufacturing of the electrically conductive parts and their required electrical insulation can be achieved, if the lead frame assembly comprises at least one metal lead frame overmolded by an electrically insulating material, wherein the electrically insulating material is further structured to form an adapter casing.

In particular, the adapter casing may comprise an electrically insulating frame element for at least partly encompassing the at least one second connector element.

A still further degree of geometric freedom can be achieved by providing an adapter unit wherein the interconnection contact comprise two essentially parallel rail elements, and wherein the at least one second connector element further comprises an intermediate contact element which is arranged between the rail elements and the contact assembly.

In order to change the position of the respective second connector element, the intermediate contact element may be slidable along the rail elements.

The present invention further relates to a method of assembling an adapter unit for an electrical component, the adapter unit comprising at least one first connector element and at least one second connector element, wherein the first connector element differs in size and/or position from the size and/or position of the second connector element, the method comprising the following steps:

providing at least one electrically conductive interconnection element for electrically interconnecting the first connector element with the second connector element, wherein the interconnection element comprises a lead frame assembly,

wherein the lead frame assembly comprises at least one interconnection contact having at least two redundant contact portions arranged at different positions, and wherein the second connector element comprises a separately formed contact assembly which is attached to only one of the redundant contact portions for defining the position of the second connector element.

Advantageously, the lead frame assembly is fabricated by overmolding at least one metal lead frame with an electrically insulating material, wherein the electrically insulating material is further structured to form an adapter casing.

Furthermore, a cover element may be attached to the adapter casing, the cover element being provided with at least one opening for accessing the at least one second connector element from outside the adapter, wherein the position of the opening defines the position of the second connector element. This facilitates the assembly process and reduces manufacturing costs.

In order to allow for the mounting of the second connector elements to be performed by an automated pick-and-place process, the contact assembly may comprise a double fork contact arranged in an electrically insulating contact assembly housing, wherein the interconnection contact comprises elongated electrically conductive rail elements, and wherein the position of the contact assembly is variable along the rail element.

According to an advantageous aspect of the inventive method, the at least one interconnection contact may comprise two essentially parallel rail elements, wherein the method further comprises the step of assembling an intermediate contact element between the rail elements and the contact assembly. In this manner, a continuous (i.e. stepless) change of position is possible for the second connector elements, so that even small position variations due to fabrication tolerances of the electrical and/or electronic component can be compensated.

The accompanying drawings are incorporated into the specification and form a part of the specification to illustrate several embodiments of the present invention. These drawings, together with the description serve to explain the principles of the invention. The drawings are merely for the purpose of illustrating the preferred and alternative examples of how the invention can be made and used, and are not to be construed as limiting the invention to only the illustrated and described embodiments. Furthermore, several aspects of the embodiments may form-individually or in different combinations-solutions according to the present invention. The following described embodiments thus can be considered either alone or in an arbitrary combination thereof. Further features and advantages will become apparent from the following more particular description of the various embodiments of the invention, as illustrated in the accompanying drawings, in which like references refer to like elements, and wherein:

FIG. 1 is an exploded perspective view of an adapter unit according to a first embodiment of the present invention;

FIG. 2 is a perspective view of the adapter unit of Fig. 1;

FIG. 3 is another perspective view of the adapter unit of Fig. 1;

FIG. 4 is a perspective view of a cover element according to a first aspect of the present invention;

FIG. 5 is a perspective view of a cover element according to a second aspect of the present invention;

FIG. 6 shows a perspective view of a header housing;

FIG. 7 shows a detail of Fig. 3 with the header housing of Fig. 6;

FIG. 8 is a schematic perspective view of a lead frame used as interconnection element in the adapter unit according to a first embodiment of the present invention;

FIG. 9 shows the lead frame of Fig. 8 after being overmolded;

FIG. 10 schematically illustrates the mounting of the second connector elements on the lead frame of Fig. 8;

FIG. 11 is a detail of Fig. 10;

FIG. 12 is a perspective view of a double fork contact;

FIG. 13 is a side view of the double fork contact of Fig. 12;

FIG. 14 shows a detail of Fig. 13;

FIG. 15 is a first perspective view of a second connector element;

FIG. 16 is a second perspective view of the second connector element shown in Fig. 15;

FIG. 17 is a plan view of the cover element according to the first aspect of the present invention shown in Fig. 4;

FIG. 18 is a plan view of the cover element according to the second aspect of the present invention shown in Fig. 5;

FIG. 19 is a plan view of a cover element according to a further aspect of the present invention;

FIG. 20 is a plan view of a cover element according to a further aspect of the present invention;

FIG. 21 is an exploded perspective view of an adapter unit according to a second embodiment of the present invention;

FIG. 22 is a perspective view of the intermediate contact element shown in Fig. 21;

FIG. 23 is a schematic perspective view of a lead frame used as interconnection element in the adapter unit according to a second embodiment of the present invention;

FIG. 24 schematically illustrates a first step of the mounting of the second connector elements on the lead frame of Fig. 23;

FIG. 25 schematically illustrates a second step of the mounting of the second connector elements on the lead frame of Fig. 23.

The present invention will now be further explained referring to the Figures, and firstly referring to Figure 1. Fig. 1 schematically illustrates a first advantageous embodiment of an adapter unit 100 in a perspective exploded view. The adapter unit 100 comprises a plurality of contact tabs 102 forming first connector elements according to the present invention. The contact tabs are connected to the second connector elements 104 via an interconnection element 106.

The interconnection elements 106 are part of a lead frame assembly 108. As shown in Fig. 1, the lead frame assembly 108 comprises interconnection contacts 110 for being contacted by the second connector elements 104. According to the present invention, each first connector element 102 is connected with two redundant interconnection contacts 110’, 110”. By connecting the second connector element 104 to one of the redundant interconnection contacts 110’ or 110” and by leaving the remaining contact unconnected, the position of the second connector elements 104 and consequently the footprint of the contact configuration is chosen.

As shown in Fig. 1, the interconnection contact 110”’ may also be formed as an elongated rail element, along which the position of the second connector element 104 is variable. This design allows additionally for compensating small variations of the position of the electronic component’s terminals due to fabrication tolerances.

According to an advantageous aspect of the present invention, the adapter unit 100 comprises a cover element 112 having openings 114 for inserting the second connector elements 104 therethrough. The position of the openings 114 thus determines the position of the connector elements and thereby the footprint offered to the electrical component (not shown in the Figures) . In other words, the cover element 112 functions as a coding means or a mask.

The cover element 112 is advantageously attached to an adapter casing 118 forming electrically insulating frames 116 around each interconnection contact 110. For fixing the cover at the adapter casing 118, one or more locking means 120 are provided at the cover element 112. For instance, the locking means 120 comprises an engagement opening for interacting with a snap-fit projection 122 arranged at the adapter casing 118. Thus, for accommodating for a different footprint of a thermostat, only a different cover element 112 having a different layout of the openings 114 has to be used; all other components can be retained, albeit interconnected differently.

As will become more apparent from the following drawings of Fig. 11 to 16, the second connector elements 104 are exemplarily formed as contact assemblies having a double fork contact 124 arranged in an electrically insulating contact assembly housing 126.

For electrically contacting the contact tabs 102, the adapter unit 100 further comprises a header housing interface 128. The header housing interface 128 can be contacted by a corresponding PAST 2.5 connector. However, it is clear for a person skilled in the art that any other suitable electrical connector design may also be used with the adapter unit 100 according to the present invention.

Furthermore, the lead frame assembly 108 comprises machining windows 130 through which the lead frame webs 132 which still connect the leads 106 can be removed, e. by laser cutting.

Finally, additional grounding terminals 134 may be provided.

Figures 2 and 3 show the adapter unit 100 in the assembled state.

As shown in Figures 4 and 5, different layouts of the openings (or cut outs) 114 in the cover element 112 define different footprints that interact with different terminal configurations at the electrical/electronic component to be contacted.

Fig. 6 illustrates the header housing interface 128 which is formed as an injection molding part that can be snap-fitted onto the lead frame assembly 108. To fix the header housing interface 128, snap-fit hooks 136 are provided which engage with a mounting recess provided at the lead frame assembly 108. Fig. 7 shows the mounted header housing interface 128 as a detail of Fig. 3. As mentioned above, the header housing interface 128 shown here exemplarily complies with a PAST 2.5 standard, but may of course also have a different configuration.

An advantageous aspect of the PAST configuration can be seen in the fact that the connectors are coded and polarized and are provided with locking means to be locked with a mating counterpart in the connected state. These features ensure that for instance that only one out of five three-position connectors which may be part of an internal wiring harness fits into the PAST header receptacle having the same coding.

With reference to Fig. 8 to 10 the functionality and manufacturing of the lead frame assembly 108 will be explained in more detail.

Fig. 8 shows the actual lead frame 140 comprising contact tabs 102 connected by interconnection elements 106 to interconnection contacts 110. In order to ease the fabrication, the various metallic leads are interconnected by webs 132 which will be removed after final assembly as required. In addition to the actual contact tabs 102 and the interconnecting elements 106 connecting them to the interconnection contacts 110, the lead frame 140 may also comprise a grounded screening element 142. The lead frame is for instance fabricated by stamping and bending from a metal sheet.

After the stamping and bending process, the lead frame 140 shown in Fig. 8 is overmolded with an electrically insulating plastic material. Thereby, the lead frame assembly 108 is formed as shown in Fig. 9. This overmolding process forms the adapter casing 118 and the mounting recess 138 for attaching the header housing interface. In order to separate the different interconnection contacts 110 which are to be electrically insulated from each other, electrically insulating frames 116 are formed around each group of contacts 110.

Fig. 10 illustrates the attachment off the second connector elements 104 to the interconnection contacts 110. In the shown embodiment, each of the interconnection contacts 110”’ omprises two electrically conductive rails. Each pair of rails is connected to one common interconnection lead 106. Consequently, the pair of rails provides redundancy and from an electrical point of view it does not have any effect at what position the contact assembly 104 is attached to a particular interconnection contact. Therefore, the geometrical layout of the contact assemblies 104 can be adapted to a footprint of e.g. a particular type of thermostat by selecting the appropriate position of the contact assemblies 104 on the rails 110. As can further be seen from Fig. 10, not only can the particular rail element 110’ or 110” be chosen, but also on each rail a desired position can be selected according to the required footprint. This change of positon is indicated by

arrows

144 and 146.

Fig. 11 shows an enlarged detail of Fig. 10. Referring to this Figure together with Figures 12 to 16, the mounting of the contact assemblies 104 will be explained in detail.

According to an advantageous embodiment of the present invention, each contact assembly 104 comprises a double fork contact 124 which is encased in a contact assembly housing 126. Each fork contact comprises two resilient contact arms 154. One of the fork contacts 148 is to be mated with the rails 110, while the other side is mateable with the terminals of the thermostat. In order to restrict the position of the contact assembly 104 on the rail elements 110’, 110”, the contact assembly housing 126 may be provided with coding ribs 150. The coding ribs 150 engage with coding slots 152 provided at the rail elements 110’, 110”.

Furthermore, a dimple 156 can be provided at each contact arm 154 of the fork contact 148 for forming a protrusion that engages with a mating locking recess 158 at the rail elements 110”’ for locking the contact assembly 104 at the rail element 110”’ . This locking feature guarantees a secure and long term stable electrical contact.

As already mentioned above, the cover element 112 defines with its insertion openings 114 the position of the contact assembly 104 during the manufacturing process. Figures 17 to 20 show four different examples of cover elements 112 that can be used with the lead frame assembly 108 shown in Fig. 9. As can be seen from these drawings, the outline of the cover elements 112 is identical and only the position of the insertion openings 114 is different, thereby defining the footprint of the adapter unit 100. Of course, these four configurations are only examples of how the footprint may be altered by using a different position of the insertion openings 114.

Fig. 21 schematically illustrates a second advantageous embodiment of an adapter unit 200 in a perspective exploded view. The adapter unit 200 comprises a plurality of contact tabs 202 forming first connector elements according to the present invention. The contact tabs 202 are connected to contact assemblies 204 forming the second connector elements via an interconnection element 206.

The interconnection elements 206 are part of a lead frame assembly 208. As shown in Fig. 21, the lead frame assembly 208 comprises interconnection contacts 210 for being contacted by the second connector elements 204. Also with the second embodiment, each first connector element 202 is connected with two redundant interconnection contacts 210. However, an intermediate contact element 221 is arranged between the interconnection contact 210 and the contact assembly 204.

The adapter unit 200 comprises a cover element 212 having openings 214 for inserting the second connector elements 204 therethrough. The positions of the openings 214 thus determine the position of the connector elements and thereby the footprint offered to the electrical component (not shown in the Figures) . In other words, the cover element 212 functions as a coding means or a mask.

The cover element 212 is advantageously attached to an adapter casing 218 forming electrically insulating frames 216 around each interconnection contact 210. For fixing the cover at the adapter casing 218, one or more locking means 220 are provided at the cover element 212. Although not shown in this Figure, the locking means 220 may interact with corresponding snap-fit projections arranged at the adapter casing 218. Thus, for accommodating for a different footprint of a thermostat, only a different cover element 212 having a different layout of the openings 214 has to be used; all other components can be retained, albeit interconnected differently.

According to the second embodiment, the second connector elements 204 are again formed as contact assemblies having a double fork contact 224 arranged in an electrically insulating contact assembly housing 226, identical to the contact assemblies shown for the first embodiment.

For electrically contacting the contact tabs 202, the adapter unit 200 further comprises a header housing interface 228 to be assembled in a mounting recess 238. The header housing interface 228 can be contacted by a corresponding PAST 2.5 connector. However, it is clear for a person skilled in the art that any other suitable electrical connector design may also be used with the adapter unit 200 according to the present invention.

Furthermore, the lead frame assembly 208 comprises machining windows 230 through which the lead frame webs 232 which still connect the leads 206 can be removed, e.g. by laser cutting. Finally, additional grounding terminals 234 may be provided.

As shown in Fig. 21, different layouts of the openings (or cut outs) 214 in the cover element 212 may define different footprints that interact with different terminal configurations at the electrical/electronic component to be contacted.

The adapter unit 200 according to the second aspect differs from the adapter unit 100 according to the first embodiment mainly in the geometry and arrangement of the second interconnection contacts 210 and the fact that additional intermediate contact elements 221 are provided to connect the contact assemblies 204 to the rail elements 210.

These differences become more apparent when additionally referring to Figures 22 to 25.

The lead frame 240 comprises redundant first rail elements 210 for each of the second interconnection contacts. The rail elements 210 extend essentially in parallel to each other and can be bridged by an intermediate contact element 221. Each intermediate contact element 221 has two fork contacts 248 which are interconnected by a second rail element 249. The intermediate contact elements 221 can be mounted along the first rail elements 210 at any desired position, thereby allowing a continuous (stepless) selection of the position of the contact assembly 204 in the direction indicated by

arrows

244 and 246. Furthermore, in order to compensate tolerances, the contact assembly 204 is additionally slidable along the second rail elements 249.

It has to be noted that no locking means are shown between the rail elements 210 and the intermediate contact element 221. However, of course, dimples and locking recesses as shown in Fig. 11 to 14 or a similar solution may also be provided. Moreover, some or all of the second rail elements 249 may also have coding slots as shown in Figures 8 to 11.

REFERENCE NUMERALS

Claims

Adapter unit for an electrical component, the adapter unit (100) comprising:

at least one first connector element (102) ,

at least one second connector element (104) , wherein the first connector element differs in size and/or position from the size and/or position of the second connector element,

at least one electrically conductive interconnection element (106) electrically interconnecting the first connector element with the second connector element, wherein the interconnection element comprises a lead frame assembly (108) ,

wherein the lead frame assembly (108) comprises at least one interconnection contact (110) having at least two redundant contact portions (110’ , 110” ) arranged at different positions, and wherein the second connector element (104) comprises a separately formed contact assembly which is attached to only one of the redundant contact portions for defining the position of the second connector element (104) .
Adapter unit according to claim 1, wherein the first connector element (102) comprises a header housing interface (128) and a plurality of first tabs arranged in the header housing interface.
Adapter unit according to claim 1 or 2, further comprising a cover element (112) which provides at least one opening (114) for accessing the at least one second connector element (104) from outside the adapter unit, wherein the position of the opening (114) defines the position of the second connector element (104) .
Adapter unit according to one of the preceding claims, wherein the second connector element (104) comprises a double fork contact (124) arranged in an electrically insulating contact assembly housing (126) .
Adapter unit according to claim 4, wherein the interconnection contact (110) comprises an elongated electrically conductive rail element (110” ’ ) , and wherein the position of the second connector element (104) is variable along the rail element, and/or wherein the interconnection contact (110) comprises at least two elongated electrically conductive rail elements (110’ , 110” ) and the position of the second connector element is determined by the position of the contact assembly on one of the rail elements.
Adapter unit according to claim 5, wherein the rail element (110” ’ ) has locking means (152, 158) for fixing the contact assembly (104) in a chosen position on the rail element.
Adapter unit according to one of the preceding claims, wherein the lead frame assembly (108) comprises at least one metal lead frame (140) overmolded by an electrically insulating material, and wherein the electrically insulating material is further structured to form an adapter casing (118) .
Adapter unit according to claim 7, wherein the adapter casing (118) comprises an electrically insulating frame element (116) for at least partly encompassing the at least one second connector element (104) .
Adapter unit according to one of the preceding claims, wherein the at least two redundant contact portions (110’ , 110” ) comprise two essentially parallel rail elements (210) , and wherein the at least one second connector element (104) further comprises an intermediate contact element (221) which is arranged between the rail elements and the contact assembly (204) .
Adapter unit according to claim 9, wherein the intermediate contact element (221) is slidable along the rail elements (210) .
Method of assembling an adapter unit for an electrical component, the adapter unit (100) comprising at least one first connector element (102) and at least one second connector element (104) , wherein the first connector element differs in size and/or position from the size and/or position of the second connector element, the method comprising the following steps:

providing at least one electrically conductive interconnection element (106) for electrically interconnecting the first connector element with the second connector element, wherein the interconnection element comprises a lead frame assembly (108) ,

wherein the lead frame assembly (108) comprises at least one interconnection contact having at least two redundant contact portions arranged at different positions (110’ , 110” ) , and wherein the second connector element comprises a separately formed contact assembly (104) which is attached to only one of the redundant contact portions for defining the position of the second connector element.
Method according to claim 11, wherein the lead frame assembly (108) is fabricated by overmolding at least one metal lead frame (140) with an electrically insulating material, and wherein the electrically insulating material is further structured to form an adapter casing (118) .
Method according to claim 12, wherein a cover element (112) is attached to the adapter casing (118) , the cover element (112) being provided with at least one opening (114) for accessing the at least one second connector element from outside the adapter unit, wherein the position of the opening (114) defines the position of the second connector element (104) .
Method according to one of the claims 11 to 13, wherein the contact assembly (104) comprises a double fork contact (124) arranged in an electrically insulating contact assembly housing (126) , wherein the at least two redundant interconnection contacts comprise elongated electrically conductive rail elements, and wherein the position of the contact assembly is variable along the rail element.
Method according to one of the claims 11 to 14, wherein the at least two redundant interconnection contact portions comprise two essentially parallel rail elements, and wherein the method further comprises the step of assembling an intermediate contact element (221) between the rail elements (210) and the contact assembly (204) .