Patent Publication Number: US-2023146927-A1

Title: An assembly for sealing a juncture of a cable in a wall

Description:
FIELD 
     The invention relates to an assembly for sealing a juncture of a cable in a wall. 
     The wall may be comprised in a casing of an (electronic) appliance. 
     The appliance includes, among other devices, a fingerprint sensor type device, a fingerprint scanner type device, a Hardware Security Module (or HSM) type device, a terminal, a mobile (tele)phone type device, a Personal Digital Assistant (or PDA), a laptop, a Personal Computer (or PC) type device, a tablet, a desktop computer, a media-player, a game console, a netbook, a handset, a user terminal and/or a set-up box type device. 
     BACKGROUND 
     It is known to connect a cable of a Universal Serial Bus (or USB) type, to a fingerprint scanner, as an appliance. The cable allows supplying power to and communicating with a circuitry comprised in the appliance. 
     However, such a cable connection does not prevent, at a juncture of the cable in an appliance casing wall, a dust and water ingress into the appliance casing. 
     There is a need of a solution that allows protecting notably, at a juncture of a cable in a casing wall, from any penetration of any foreign matter into the casing. 
     SUMMARY 
     Provided is a solution for satisfying the just herein above specified need by providing an assembly for sealing a juncture of a cable in a wall. 
     According to the invention, the wall includes at least one aperture. The aperture is used for coupling a connector comprised within the cable. A cable end is provided with at least one flange. The flange surrounds at least in part the cable end. The assembly includes at least one strain relief element. The strain relief element is configured, once in a position to cooperate with the wall and the flange, to press, directly or indirectly, the flange against the wall when the connector is coupled while the strain relief element remains attached to the wall, so that the flange surrounds, directly or indirectly, the aperture and prevents, directly or indirectly, any foreign matter from passing the juncture of the cable at the aperture. 
     In a further aspect, the invention also provides an assembly for sealing a juncture of a cable in a wall, wherein, the wall including at least one aperture, the aperture being used for coupling a connector comprised within the cable, a cable end being provided with at least one flange, the flange surrounding at least in part the cable end, the assembly including at least one strain relief element, the strain relief element comprising:
     a main wall comprising a slot on an edge in the form of a cut-out, the slot being configured to receive a portion of the cable smaller than the portion provided with the flange,   at least one pillar protruding from the main wall, wherein each of the at least one pillar is configured to push the flange against the wall when the connector is coupled while the strain relief element remains attached to the wall,   
 so that the flange surrounds, directly or indirectly, the aperture and seals, directly or indirectly, the juncture of the cable at the aperture. This entails preventing, directly or indirectly, any foreign matter such as dust and/or water from passing the juncture of the cable at the aperture.
     The principle of the invention consists in providing, on one hand, a flange(s) on a cable end and, on another hand, a strain relief element(s). The strain relief element is designed, once positioned to cooperate with a wall and the flange, to urge, directly or indirectly, the flange against the wall, while the strain relief element is fixedly retained by the wall and the connector is coupled through a wall aperture. The wall aperture is thus hermetically shrouded, by or thanks to the flange that is urged by the strain relief element, at one side of the wall. No foreign matter is thus able to cross the wall, i.e. from one side to the other side of the wall, at the juncture of the cable at the wall aperture. 
     In the present description, the adverb “directly” means without using any external additional element while the adverb “indirectly” means using one or several external additional elements, such as e.g., one or several gaskets. 
     The invention solution allows preventing from any passage of any foreign matter, such as dust and/or water, at the wall aperture. 
     The invention solution therefore renders a juncture of a cable in a wall dustproof and waterproof. 
     Moreover, the invention solution is robust in time while retaining the sealing capacity of the assembly thanks to the used strain relief element(s). 
     The invention solution is technically simple and efficient against a passage of any foreign matter through a wall aperture used for connecting the cable. 
     According to a first embodiment, the assembly further includes at least one external elastic element. The at least one elastic element is placed, prior to coupling the connector, around the cable at the front of the flange, so that the strain relief element presses the flange and the at least one elastic element together against the wall when the connector is coupled while the strain relief element remains attached to the wall. 
     According to a second embodiment, the flange is at least in part constituted by at least one elastic material, so that the strain relief element presses the flange and the flange elastic part together against the wall when the connector is coupled while the strain relief element remains attached to the wall. 
     Preferably, the strain relief element further includes at least one pillar. Each of the at least one pillar allows pushing, directly or indirectly, the flange, to the wall. 
     Preferably, the strain relief element further includes at least one protruding extension. Each of the at least one protruding extension allows, on one hand, coupling the strain relief element to the wall and, on another hand, retaining the strain relief element coupled to the wall. 
     According to a first embodiment, the at least one protruding extension forms, each, a sliding guide that allows guiding the strain relief element during an insertion of the strain relief element into a corresponding gutter comprised within the wall. 
     According to a second embodiment, the at least one protruding extension allows, each, attaching the strain relief element to the wall during a coupling of the strain relief element with a corresponding recess comprised within the wall. 
     Advantageously, the strain relief element includes at least one rib. The at least one rib allows avoiding a shrinking of the strain relief element and/or a warpage of the strain relief element after having been molded. The at least one rib is configured to add robustness to the strain relief element in use, that is, making the strain relief element more robust for use. 
     In a preferred embodiment, the cable includes the connector, as a first connector. The wall is included within a casing. The casing includes a second connector. The second connector faces, within the casing, the aperture. The first connector and the second connector are connected to each other. 
     Preferably, the strain relief element is outside the casing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Additional features and advantages of the invention will be apparent from a detailed description of two preferred invention embodiments, given as indicative and non-limitative examples, in conjunction with the following drawings: 
         FIG.  1    is a perspective view of an interior of an appliance casing with a wall aperture used for coupling a connector at a cable end provided with a releasable elastic element and an integrated flange to be pressed by a detachable strain relief element, as external elements, according to a first embodiment of the strain relief element; 
         FIG.  2    is a perspective view of an exterior of the appliance casing with the wall aperture by using the external elements of  FIG.  1   ; 
         FIG.  3    is a front view of the wall aperture sealed by using the external elements of  FIG.  1    when the external elements cooperate with each other to seal a juncture of the cable end in the wall by using the strain relief element; 
         FIG.  4    is a side view along the section A-A line of  FIG.  3   ; 
         FIG.  5    is a top view along the section B-B line of  FIG.  3   ; 
         FIG.  6    is a perspective view of an exterior of an appliance casing with a wall aperture used for coupling a connector at a cable end provided with a releasable elastic element and an integrated flange to be pressed by a detachable strain relief element, as external elements, according to a second invention embodiment of the strain relief element; 
         FIG.  7    is another perspective view of the elements of  FIG.  6   ; 
         FIG.  8    is a front view of the wall aperture sealed by using the external elements of  FIG.  7    when the external elements cooperate with each other to seal a juncture of the cable end in the wall by using the strain relief element; and 
         FIG.  9    is a side view along the section A-A line of  FIG.  8   . 
     
    
    
     DETAILED DESCRIPTION 
     Herein under is considered a case in which the invention assembly is used for sealing a juncture of a cable of a USB type in a wall. 
     However, the invention assembly may be used for sealing a juncture of any type of cable in a wall. 
     The cable may include, among others, a mechanical type cable, a non-electrical type cable, an electrical type cable, a power supply type cable and a communication type cable. The aforementioned cable type set is not exhaustive. 
     Naturally, the herein below described embodiments are only for exemplifying purposes and are not considered to reduce the scope of the invention. 
     The same references that are present in different figures refer to one and the same elements. 
       FIG.  1    presents schematically a wall  10  with an aperture  104  and an exploded view of an assembly  200  for sealing a juncture of a cable  20  in the wall  10  in a rear and top view. 
     The wall  10  may be included within a housing or casing (represented in part). 
     The casing may include several walls including the wall  10 , as a first wall. 
     For a sake of simplicity, only the first wall  10  of the casing has been represented. 
     The casing may include a Printed Circuit Board (or PCB) (not represented) that comprises one or several (electrical and/or electronic) circuits. 
     The wall  10  may be made of e.g., a hard plastic type material. Alternatively, the wall  10  is made of metal, wood, a combination or mixture thereof or (an)other material(s). 
     The wall  10  includes one or several apertures  104  (only one being represented). 
     The aperture  104  constitutes a through hole, as a passage. 
     The aperture  104  is used for coupling a connector  26 . The connector  26  is provided at a cable end  24 . 
     The connector  26  includes one or several terminations of conductors comprised within the cable  20 . 
     The PCB may be connected, through another connector, to the connector  26 , that is connected, at the other end of the cable  20 , to an external device, such as a PC, so as to exchange data with each other and/or to supply in power the PCB or the external device. 
     The connector  26  includes e.g., a USB 3.0 B type plug. 
     The aperture  104  may have a substantially rectangular form. Alternatively, the aperture  104  may have a form that is substantially circular, oval, square, hexagonal or any other form. The aperture  104  form conforms to the form of the cross-section of the cable end  24  that has to cross the wall  10  at the aperture  104 . 
     The wall  10  divides a space in two sub-spaces, namely, at a first side of the wall  10 , an interior  100   a  of the casing and, at a second side of the wall  10 , an exterior  100   b  of the casing. 
     The aperture  104  allows accessing from the casing exterior  100   b  into the casing interior  100   a  and/or conversely, i.e. from the casing interior  100   a  into the casing exterior  100   b . 
     The aperture  104  may allow, when at least partially open, dust, gas, a liquid(s) and/or any foreign material, to flow from the casing exterior  100   b  to the casing interior  100   a  and/or conversely, i.e. from the casing interior  100   a  to the casing exterior  100   b . 
     The wall  10  has, at the aperture  104 , a rear face  110  that is opposite to a front face that faces the connector  26  to be engaged or inserted into the aperture  104 . 
     The wall  10  may have a recess  106 . The recess  106  is preferably completely molded with the wall  10 , so as to form one and the same element with the wall  10 . 
     The cable  20  includes a main body  27  that is preferably relatively flexible. 
     The main body  27  is made of e.g., a plastic type material. The main body  27  may be substantially cylindrical or any other form, such as a substantially parallelepiped shape. 
     The main body  27  has, when cylindrical, a radius of the external circle of e.g., about a few mm and may be comprised in a range from about 2 mm to about 8 mm. 
     The main body  27  may be overlaid, at the cable end  24 , with an additional layer  25 , so as to rigidify and reinforce the cable end  24  for its manipulation by a user to connect or disconnect the connector  26 . 
     The additional layer  25  may be made of e.g., a plastic type material. The additional layer  25  is preferably overmolded about the main body  27 . The additional layer  25  may be substantially cylindrical or have any other form, such as a substantially parallelepiped shape. 
     The additional layer  25  is used for avoiding a tight curvature of the cable  20  that may damage a possible internal wire(s) and therefore a connection. 
     The additional layer  25  has, when cylindrical, a diameter of the external circle of e.g., about a few mm with respect to the main body  27  and may be comprised in a range from about 1 mm to about 11 mm. 
     The additional layer  25  and/or the main body  27  may be overlaid, at the cable end  24 , with a transition layer  23 , so as to make a transition or a bridge between the main body  27  and/or the additional layer  25  and a gripping layer  21 . 
     The transition layer  23  may be made of e.g., a plastic type material. The transition layer  23  is preferably overmolded about the main body  27  and/or the additional layer  25 . The transition layer  23  may have a form that is substantially e.g., a truncated pyramid, any other form, such as a substantially parallelepiped shape, or a truncated cylindrical cone. The smallest base of the truncated pyramid (or the like) of the transition layer  23  is preferably prolonged by the main body  27  and/or the additional layer  25  while the largest base of the truncated pyramid (or the like) of the transition layer  23  is preferably prolonged by the gripping layer  21 . The cross-section of the transition layer is e.g., rectangular. 
     The length of the largest side of the smallest base of the truncated pyramid (or the like) of the transition layer  23  may be e.g., about 9 mm and is preferably at least as wide as the diameter of the additional layer  25 , when present, or the diameter of the main body  27 , if the additional layer  25  is not present. 
     The length of the largest side of the largest base of the truncated pyramid (or the like) of the transition layer  23  may be e.g., about 12 mm and is preferably as wide as the lateral side of the gripping layer  21 . 
     The length of the smallest side of the smallest base of the truncated pyramid (or the like) of the transition layer  23  may be e.g., about 7 mm and is preferably at least as wide as the diameter of the additional layer  25 , when present, or the diameter of the main body  27 , if the additional layer  25  is not present. 
     The length of the smallest side of the largest base of the truncated pyramid (or the like) of the transition layer  23  may be e.g., about 11 mm and is preferably at least as wide as the diameter of the additional layer  25 , when present, or the diameter of the main body  27 , if the additional layer  25  is not present. 
     The gripping layer  21  is provided at the front of the cable end  24  for its grip between fingers of the user who manipulates at the gripping layer  21  the cable end  24  to be plugged into or unplugged from the wall  10 . The gripping layer  21  constitutes at least in part a gripping area that is suitable for a user manipulation. 
     The gripping layer  21  may be made of e.g., a plastic type material that is preferably harder than the main body  27  material, when also made of a plastic type material. The gripping layer  21  is preferably molded with the main body  27 , the additional layer  25  and/or the transition layer  23 , so as to form one and the same element with the concerned cable portions or elements. The gripping layer  21  may have a substantially parallelepiped form. Alternatively or additionally, the gripping layer  21  is substantially cylindrical or has any other form. 
     The gripping layer  21  includes preferably one or several flat surfaces that may be, two by two, parallel with each other. Such a flat surface(s) allow(s) facilitating the grip of the cable end  24  by the user to plug the cable end  24  into the wall  10  or unplug the cable end  24  from the wall  10 . 
     The length of the gripping layer  21  may be e.g., about 1.5 cm and may be comprised in a range from about 10 mm to about 60 mm. 
     The length of the cable end  24  may be e.g., about 4 mm and may be comprised in a range from about 1 mm to about 5 mm. 
     According to an essential feature, the cable  20  is provided, at the cable end  24 , with one or several flanges  22  (only one being represented). 
     The (or each) flange  22  is preferably integrally molded with the cable end  24 , so as to form one and the same element with the cable  20 . 
     The thickness of the flange  22  may be e.g., about a few mm and may be comprised in a range from about 1 mm to about 5 mm. 
     Alternatively, i.e. instead of being a flange incorporated in the cable  20 , as an internal flange, the (or each) flange  22 , as an external flange, consists of one or several external additional elements that are fixed using, e.g., a glue(s) or welding any other fixing means, around the cable end  24 . 
     The cross-section of the flange  22  may be substantially rectangular while being preferably rounded at the external corners. 
     The (or each) flange  22  is preferably made of e.g., a hard plastic type material and/or the like, at least at the back of the flange  22 , so as to be pushed from the back of the flange  22  in a direction  50  towards the rear face of the wall  10 , as the push direction  50 . 
     The (or each) flange  22  forms or constitutes preferably one or several shoulders. Such a shoulder(s) (formed by the flange  22 ) is (are) substantially perpendicular to an axis that is defined by the cable  20  at the cable end  24 . Such a shoulder(s) allow(s) applying a force that is substantially parallel to the cable  20  at the cable end  24  and that points in the push direction  50 . 
     The (or each) flange  22  may have an external form that is substantially e.g., rectangular that may be rounded on its external corners, or any other form. 
     The length of the largest side of the external rectangular of the flange  22  may be e.g., about 1.7 cm and may be comprised in a range from about 1 cm to about 4 cm. 
     The length of the smallest side of the external rectangular of the flange  22  may be e.g., about 1.5 cm and may be comprised in a range from about 1 cm to about 4 cm. 
     The (or each) flange  22  surrounds in part, such as e.g., in a discontinued manner, or totally the cable end  24 , so that, when the (or each) flange  22  is pushed, the (or each) flange  22  seals, directly or indirectly, a juncture of the cable  20  at the aperture  104 . 
     In a preferred embodiment, the flange  22  surrounds completely the cable end  24 . 
     Such a flange  22  surrounding is preferably present at the front of the gripping layer  21 , so as to facilitate an insertion of the cable end  24  into the aperture  104  while using the flange  22  as one or several stops for notably a user finger(s) or a detachable strain relief element(s)  30  to push the cable end  24  in the push direction  50 . 
     The (or each) flange  22  is used so that the detachable (or attached) strain relief element(s)  30  is(are) in capacity to press, directly or indirectly, the flange  22  against the wall  10  from the exterior  100   b . 
     The (or each) flange  22 , once in cooperation with the wall  10  and the strain relief element  30 , is able to surround, directly or indirectly, the aperture  104  and prevents, directly or indirectly, any foreign matter, like e.g., dust and/or water, from passing the juncture of the cable  20  at the aperture  104 , as described infra. 
     The assembly  200  may include one or several gaskets  28 , as an external releasable (or attached) elastic element(s). 
     Alternately or additionally, instead of using a gasket  28 , the rear face of the wall  10  is provided, around the aperture  24 , with an elastic element that is either integrated in the wall  10  or fixed to the wall  10  while protruding from the rear face of the wall  10 . 
     The (or each) gasket  28  may be made of e.g., rubber, and/or any other elastic material. 
     The (or each) gasket  28  is elastically deformable. 
     The (or each) gasket  28  has, in the middle, a through hole, so as to form a ring. 
     The (or each) gasket  28  has preferably substantially the form of the flange  22 . The flange  22  thus enters in physical contact with the periphery of the gasket  28  preferably all around the periphery of the flange  22 . 
     The cross-section of the gasket  28  may be substantially circular, oval, rectangular, square or have any other form. 
     The thickness of the gasket  28  may be e.g., about 1 mm and may be comprised in a range from about 0.8 mm to about 4 mm. 
     The (or each) gasket  28  is able to penetrate and/or be penetrated by, through its hole, the cable end  24 . 
     The (or each) gasket  28  (when present) is preferably used for being placed around the cable  20  and preferably at the front of the flange  22 , prior to coupling the connector  26 . 
     Additionally or alternately, i.e. instead of using the gasket(s)  28  and/or an elastic element integrated in or fixed to the rear face of the wall  10 , as an external elastic element(s), the flange  22  is overmolded (or overlaid), at the front of the flange  22 , by an elastic or elastomeric material, as an internal elastic element. 
     The flange  22  is at least in part constituted by at least one elastic or elastomeric material, at least at the front of the flange  22 . 
     The internal elastic or elastomeric layer of the flange  22  is elastically deformable at least at a sealing area with the wall  10 . The internal elastic layer of the flange  22 , as an elastic element internal to the flange  22 , or the gasket  28 , as an elastic element external to the flange  22 , is used for sealing a juncture of the cable end  24  in the wall  10  at the aperture  104 . 
     The wall recess  106  is preferably arranged, so as to accommodate the flange(s)  22 , the strain relief element(s)  30  and possibly the gasket(s)  28 , as external elements. 
     The strain relief element  30  is preferably made of e.g., a hard plastic type material or the like. 
     The strain relief element  30  includes a main wall  32 . 
     The main wall  32  has a rear face  33  that is opposite to a front face  31 . 
     The strain relief element  30  includes two side walls  33   a  and  33   b  that extend to the main wall  32 . The side walls  33   a  and  33   b  have, each, substantially e.g., a form of a perpendicular triangle that is truncated e.g., at the bottom of the main wall  32  and the truncated side is parallel to the opposite side e.g., at the top of the main wall  32  while its largest side constitutes the lateral limit of the main wall  32 . 
     Optionally, the strain relief element  30  includes a plate  37 . The plate  37  is situated at the bottom of the main wall  32 . The plate  37  forms a foot for the strain relief element  30  when seen laterally. 
     The plate  37  may have e.g., a rectangular form, when seen from the top or the bottom of the strain relief element  30 . 
     The external corners of the plate  37  may be rounded. 
     The smallest side of the plate  37  may be e.g., about 1 cm and may be comprised in a range from about 0.5 mm to about 50 mm. 
     The largest side of the plate  37  may be e.g., about 2.3 cm and may be comprised in a range from about 1.5 cm to about 4.5 cm. 
     The thickness of the plate  37  may be e.g., about a few mm and may be comprised in a range from about 0.3 mm to about 4 mm. 
     Optionally, the strain relief element  30  has e.g., at the plate  37 , one or several through holes  38   a  and  38   b . Each hole  38   a  or  38   b  is used for passing a fastening element (not represented), such as a screw. The fastening element(s) allow(s) fastening the strain relief element  30  to the wall  10  or another wall that may be comprised in the casing. 
     The main wall  32  comprises preferably a slot  36 . 
     The slot being arranged on an edge of the main wall  32  in the form of a cut-out. 
     The slot being configured to receive a portion of the cable smaller than the portion provided with the flange. 
     The slot  36  is defined by a through hole that is laterally bordered by two pillars  31   a  and  31   b  which are connected by a beam  31   c . 
     The slot  36  allows a passage of the gripping area  21  through the strain relief element  30 . 
     The main wall  32  of the strain relief element  30  is inclined backwards, i.e. in the opposite direction of the push direction  50 , to align the shape of the rear face of the main wall  32  with the shape of the rear face of the wall  10 . Thus, the strain relief element  30  may be perfectly integrated in the rear face of the wall  10 . 
     The slot  36  has a form that conforms to the form of the cross-section of a part of the cable  20 , like e.g., the gripping area  21 . 
     The side walls  33   a  and  33   b  are e.g., symmetric with respect to a row that crosses the middle of the slot  36  termed middle row hereafter. 
     Optionally, the strain relief element  30  includes one or several ribs (not represented). When there are an even number of ribs, the ribs are preferably symmetric with respect to the middle row. The rib(s) is(are) placed under the slot  36  and provided preferably on the rear face  33  of the main wall  32 . The rib(s) allow(s) avoiding a shrinking of the strain relief element  30  and/or a warpage of the strain relief element  30  (just) after having been molded. The rib(s) allow(s) making the strain relief element  30  more robust for use and retaining the strain relief element  30  with the time and allow(s) avoiding affecting the external form or design of the strain relief element  30 . 
     The strain relief element  30  includes preferably one or several pillars  34   a  and  34   b . 
     The pillar(s)  34   a  and  34   b  protrude(s) from the rear face  33  of the main wall  32 . The pillar(s)  34   a  and  34   b  border(s) preferably the slot  36 . The pillar(s)  34   a  and  34   b  may, each, lean against its respective side wall  33   a  and  33   b . The pillar(s)  34   a  and  34   b  has(have), each, preferably its(their) front side that has a form that conforms to the form of the lateral sides of the flange  22 . 
     The pillar(s)  34   a  and  34   b  allow(s) sliding, prior to or after having possibly installed the (or each) gasket  28  around the front of the flange  22 , the flange  22  along the front of the pillar(s)  34   a  and  34   b . 
     The front face of the pillar(s)  34   a  and  34   b  is preferably parallel to the rear face of the lateral sides of the flange  22 , so as to apply a continuous contact with the rear face of the lateral sides of the flange  22 . 
     Each of the pillars  34   a  and  34   b  allows thus pushing or pressing, directly or indirectly, the flange  22  to the rear face of the wall  10 . 
     Each of the pillars  34   a  and  34   b  is designed to push and maintain a push or pressure, directly or indirectly, of the flange  22  towards the rear face of the wall  10 . 
     The thickness of each of the pillars  34   a  and  34   b  of the slot  36  may be e.g., about 2 mm and may be comprised in a range from about 1 mm to about 5 mm. 
     The length of each of the pillars  34   a  and  34   b  of the slot  36  may be e.g., about 1.3 cm and may be comprised in a range from about 1 cm to about 4 cm. 
     The strain relief element  30  includes preferably one, two or more protruding extensions  32   a  and  32   b . The protruding extension(s)  32   a  and/or  32   b  allow(s), each, on one hand, coupling the strain relief element  30  to the wall  10 , and more exactly the rear face of the wall  10 , and, on another hand, retaining the strain relief element  30  coupled to the wall  10 , as further explained infra. 
     The lateral inclination of the main wall  32  with respect to the lateral protruding portion of the protruding extension  32   a  or  32   b  may be e.g., about 9 degrees and may be comprised in a range from about 1 degree to about 20 degrees. 
     According to a first embodiment of the strain relief element  30  represented on  FIGS.  1 - 5   , the protruding extensions  32   a  and/or  32   b  form(s), each, a sliding guide that allows guiding the strain relief element  30  during an insertion of the strain relief element  30  into a corresponding gutter  102   a  and  102   b  respectively (not visible on  FIG.  1   ) comprised within the wall  10 . 
     A protruding portion of the protruding extensions  32   a  and  32   b  borders laterally the strain relief element  30 . 
     The protruding extensions  32   a  and  32   b  may be, each, perpendicular to the plate  37 , when seen from a lateral side of the strain relief element  30 . 
     The protruding extensions  32   a  and  32   b  are e.g., symmetric with respect to the middle row. 
     The protruding extensions  32   a  and  32   b  have, each, when seen from the rear, substantially e.g., a form of a perpendicular triangle that is slightly truncated at the opposite side of the right angle. 
     The length of the smallest side that is adjacent to the right angle of the protruding extension(s)  32   a  and/or  32   b  may be e.g., about 3 mm and may be comprised in a range from about 1 mm to about 15 mm. 
     The length of the largest side that is adjacent to the right angle of the protruding extension(s)  32   a  and/or  32   b  may be e.g., about 4.3 cm and may be comprised in a range from about 1 mm to about 15 mm. 
     The largest side of the corresponding perpendicular triangle constitutes the outer edge of the concerned protruding extension  32   a  or  32   b  and also constitutes, in part, the outer edge of the strain relief element  30 , e.g., at the lateral side of the strain relief element  30 . 
     The truncated side constitutes the outer edge of the concerned protruding extension  32   a  or  32   b  and also constitutes, in part, the outer edge of the strain relief element  30 , e.g., at the top of the strain relief element  30 . 
     The protruding extensions  32   a  and  32   b  are connected, from their front, to the plate  37  and, from their rear, to their respective side walls  33   a  and  33   b . Each protruding extension  32   a  or  32   b  protrudes, on one hand, from its respective side wall  33   a  or  33   b  and, on another hand, laterally from the plate  37 . 
     The protruding extensions  32   a  and  32   b  protrude, each, from its respective side wall  33   a  and  33   b  respectively toward the outside of the strain relief element  30 . 
     The thickness of the protruding extension(s)  32   a  and/or  32   b  may be e.g., about 1 mm and may be comprised in a range from about0.8 mm to about 3 mm. 
     The protruding portion of each of the protruding extensions  32   a  and  32   b  is designed to conform substantially to the form of the corresponding gutter  102   a  or  102   b  comprised within the wall  10 , according to a first embodiment. 
       FIG.  2    shows schematically, in a front and bottom view, the wall  10  and the assembly  200  for sealing a juncture of the cable  20  in the wall  10  by using the strain relief element  30  according to the first embodiment. 
     Each of the gutters  102   a  and  102   b  constitutes a cut-out area on the inside of a corresponding lateral side of the recess  106 . 
     The thickness of the gutters  102   a  and/or  102   b  may be e.g., about 2 mm and may be comprised in a range from about 1 mm to about 3.5 mm. 
     Each of the gutters  102   a  and  102   b  allows accommodating a corresponding protruding extension  32   a  or  32   b , and more exactly the protruding portion of the protruding extension  32   a  or  32   b . 
     The cable  20  is to be connected to the wall aperture  104  by using the external elements of the assembly  200  to assemble all together. 
     According to a first embodiment, the assembly  200  includes the external elements, namely the flange  22 , the strain relief element  30  and the gasket  28 . 
     The form and the size of the slot  36  are configured to accommodate the gripping layer  21  of the cable  20 . 
     The length of each of the pillars  31   a  and  31   b  that borders the slot  36  is e.g., about 1.6 cm and may be comprised in a range from about 1.5 cm to about 5 cm. 
     The length of the beam  31   c  of that borders slot  36  may be e.g., about 1.4 cm and may be comprised in a range from about 1 cm to about 5 cm. 
     The thickness of the pillars  31   a  and  31   b  and the beam  31   c  that border the slot  36  may be e.g., about 2 mm and may be comprised in a range from about 1 mm to about 4 mm. 
     According to the first embodiment of the strain relief element  30 , the protruding extension(s)  32   a  and/or  32   b  form, each, a sliding guide and allows guiding the strain relief element  30  during an insertion of the strain relief element  30  into a corresponding gutter  102   a  and/or  102   b  respectively comprised within the wall  10 . 
     According to the first embodiment of the strain relief element  30 , the protruding extension(s)  32   a  and  32   b  form, each, a rail that allows coupling the strain relief element  30  to the wall  10 , and more exactly to the front face  112  of the wall  10 . 
     Prior to connecting the cable  20  to the wall  10 , the user firstly installs, e.g., with one hand, the gasket  28  around the cable end  24  that is held with e.g., another hand. 
     The gasket  28 , when used, and the strain relief element  30  are preferably, each, e.g., outside the casing that includes the wall  10 . 
     After the user has installed the gasket  28  around the cable end  24 , the user inserts the connector  26  into the aperture  104  by holding with fingers the gripping area  21  and pushing the cable  20  toward the wall  10 . Such a connector insertion is e.g., used for connecting the connector  26  to another connector  46  (visible on  FIG.  4   ). 
     Once the connector  26  is inserted in the aperture  104 , the gasket  28  is blocked, at the recess  106 , between the front face  112  of the wall  10  and the flange  22 . 
     The user inserts and slides, in a sliding direction  70 , the protruding extension(s)  32   a  and/or  32   b  in the corresponding gutter(s)  102   a  and/or  102   b  (which appears slightly) of the wall  10  until the pillars  31   a  and  31   b  bordering the slot  36  are stopped by the upper border of the recess  106 . Optionally, the user slides, in the sliding direction  70 , the protruding extension(s)  32   a  and/or  32   b  in the corresponding gutter(s)  102   a  and/or  102   b  of the wall  10  until the plate  37  reaches, simultaneously to the stopping of the pillars  31   a  and  31   b , the upper border of another recess  108  comprised possibly in another wall comprised preferably in the casing. 
     Each of the protruding extensions  32   a  and  32   b  allows, on one hand, coupling the strain relief element  30  to the wall  10  and, on another hand, retaining the strain relief element  30  coupled to the wall  10 . 
     Once the strain relief element  30  is coupled to the wall  30 , the user may furthermore insert each of one or two (or more) screws (not represented) through the hole  38   a  or  38   b  of the strain relief element  30  and a corresponding non-through hole  108   a  or  108   b  of another wall (or the wall  10 ). Then, the user turns the screw(s) in the concerned hole(s)  38   a  and/or  38   b  and the concerned non-through hole(s)  108   a  and/or  108   b , so as to fasten the strain relief element  30  to the wall  10  or another wall that is preferably included in the casing. 
     To unplug or unconnect the cable  20  from the wall  10  or the casing, the user may firstly remove the retaining screw(s) or any other fastening element(s) from the concerned non-through hole(s)  108   a  and/or  108   b  and hole(s)  38   a  and/or  38   b . 
     The user slides, in a direction opposite to the sliding direction  70 , the protruding extension(s)  32   a  and/or  32   b  in the corresponding gutter(s)  102   a  and/or  102   b  of the wall  10  by pushing with e.g., a finger, on the beam  31   c  of the slot  36  until the strain relief element  30  is released from the wall  10 . 
     The strain relief element  30  is thus decoupled and detached from the wall  10 . 
     Then, the user takes the cable end  24  away from the aperture  104  by holding with fingers the gripping area  21  and pulling the cable  20  from the wall  10 . 
     The user may remove the gasket  28  from the cable end  24 , so as to disassemble the assembly  200 . 
       FIG.  3    shows schematically from a rear view the connector  26  inserted in the wall  10  with two cross-section lines, a cross-section line A-A and a cross-section line B-B. 
     The cross-section line A-A vertically crosses the cable  20  along its diameter and the slot  30  at the middle row. 
     The cross-section line B-B is perpendicular to the first cross-section line A-A. The cross-section line B-B horizontally crosses the cable  20  along its diameter. 
     The strain relief element  30  is configured, once in a position to cooperate with wall  10  and the flange  22 , to press, directly or indirectly, the flange  22  against the wall  10  when the connector  26  is coupled while the strain relief element  30  remains attached to the wall  10 . 
     Thus, the flange  22  surrounds, directly or indirectly, the aperture  104  and prevents, directly or indirectly, any foreign matter from passing the juncture of the cable  20  at the aperture  104 . 
     The strain relief element  30  presses the lateral sides of the flange  22  through the pillars  34   a  and  34   b  (hidden on  FIG.  3   ) which extend respectively the pillars  31   a  and  31   b  which border the slot  36 . 
     The aperture  104  is closed with the cable end  24  provided with the flange  22  that seals, through either the gasket  28 , as an external elastic element in a first embodiment that is further described infra, or an elastic portion of the flange  22 , as an internal elastic element, thanks to the strain relief element  30 . 
     Once positioned to cooperate with the wall  10  and the flange  22 , the rear face  31  of the strain relief element  30  may be completely integrated in the wall  10 , i.e. no part of the strain relief element  30  protrudes from the wall  10 . 
     The strain relief element  30  is coupled to the wall  10  that may be comprised within a casing. 
       FIG.  4    shows schematically, along the cross-section line A-A, the cable end  24  inserted in the wall  10 , the gasket  28  pressed by the flange  22  and the strain relief element  30  that presses the flange  22 . 
     The casing includes e.g., the connector  46 , as a first connector. The first connector  46  is fixed within the casing. The first connector  46  faces, within the casing, the aperture  104  of the wall  10  (represented with a first hatched area). 
     The cable  20  includes a corresponding connector  26 , as a second connector. 
     The first connector  46  and the second connector  26  are connected to each other. The first connector  46  is e.g., a female connector while the second connector  26  is e.g., a male connector or the reverse, namely the first connector  46  is e.g., a male connector while the second connector  26  is e.g., a female connector. 
     The strain relief element  30  presses the flange  22  and an elastic element, namely the gasket  28 , as an external elastic element, or an elastic part of the flange  22 , as an internal elastic element (not represented), together against the wall  10  when the connector  26  is coupled to another connector  46  while the strain relief element  30  remains attached to the wall  10 . 
     According to the alternative embodiment, the strain relief element  30  presses the flange  22  and the flange elastic part, so that the strain relief element  30  presses the flange  22  and the flange elastic part together against the wall  10  when the connector  26  is coupled to another connector  46  while the strain relief element  30  remains attached to the wall  10 . 
     The pillar  34   a  (represented with a non-hatched area) and the pillar  34   b  (not visible on  FIG.  4   ) of the strain relief element  30  (represented with a second hatched area) exert, each, a pressure force, in a pressure direction  80 , on the flange  22  toward the wall  10 . 
     The flange  22  exerts, in turn, the same pressure force, in the pressure direction  80 , on the gasket  28  (represented with a blackened area) toward the wall  10 . 
     The gasket  28  which is blocked or stopped, on one side, by the rear face  112  of the wall  10  and pushed, on another side, through the front face of the flange  22 , by the pillars  34   a  and  34   b  of the strain relief element  30 , deforms elastically. 
     The gasket  28 , as an external elastic element, is thus compressed against the wall  10  and surrounds the aperture  104 . The gasket  28  seals the juncture of the cable  20  in the wall  10 . 
     In reaction to the pressure force exerted on the stopped gasket  28  by the flange  22 , the gasket  28  exerts a reaction force toward the flange  22 , in a direction opposite to the pressure direction  80 , as a reaction direction  90 . 
     The first connector  46  and the second connector  26  are connected to each other, so that a power supply of the internal circuits is possible and the internal circuits are able to communicate with an external device, such as a PC. 
     Once the first connector  46  and the second connector  26  are connected to each other, the corresponding appliance is able to operate. 
       FIG.  5    shows schematically, along the cross-section line B-B, the cable end  24  inserted in the wall  10 , the gasket  28  pressed by the flange  22  and the strain relief element  30  that presses the flange  22 . 
     According to the first embodiment of the strain relief element  30 , the protruding portion of each of the protruding extensions  32   a  and  32   b  of the strain relief element  30  is blocked within the corresponding gutter  102   a  and  102   b  included within the wall  10 . 
     Each of the gutter  102   a  and  102   b  has e.g., a U-shaped with a first lateral side that is proximate to the rear face  112  of the wall  10  and a second lateral side that is remote from the rear face  112  of the wall  10 . 
     Each of the gutter  102   a  and  102   b  is designed to accommodate the protruding portion of the protruding extension(s)  32   a  and  32   b  of the strain relief element  30 . 
     Each of the protruding extensions  32   a  and  32   b  of the strain relief element  30  that is stopped by the remote side (from the rear face  112  of the wall  10 ) of the corresponding gutter  102   a  or  102   b  allows opposing to the reaction force  90  exerted, via an elastic element, namely the gasket  28 , as an external elastic element, or an elastic part of the flange  22 , as an internal elastic element (not represented), from the wall  10  (and more exactly its front face  112 ), through the flange  22 , to the strain relief element  30 . 
     Each of the protruding extensions  32   a  and  32   b  of the strain relief element  30  allows retaining the strain relief element  30  coupled to the wall  10 . 
       FIG.  6    shows schematically, in a front and bottom view, a wall  101 , according to a second embodiment, and the assembly  200  for sealing a juncture of the cable  20  in the wall  101 , by using a strain relief element  50  according to a second embodiment. 
     The wall  101  includes a recess  150 . 
     The wall  101  comprises a plurality of coupling/decoupling recesses  152   a ,  152   b  (not visible on  FIG.  6   ),  152   c  and  152   d . 
     Each of the coupling/decoupling recesses  152   a ,  152   b ,  152   c  and  152   d  constitutes either a non-through hole or a through hole on the inside of the recess  150  of the wall  101  or another wall. 
     Each of the coupling/decoupling recesses  152   a ,  152   b ,  152   c  and  152   d  allows coupling and decoupling a corresponding protruding extension  52   a ,  52   b  or  52   c  (not visible on  FIG.  6   ) of the strain relief element  50 . 
     The thickness of the coupling/decoupling recesses  152   a ,  152   b ,  152   c  and  152   d  may be e.g., about 2 mm and may be comprised in a range from about 1 mm to about 5 mm. 
     Each of the coupling/decoupling recesses  152   a ,  152   b ,  152   c  and  152   d  allows accommodating at least in part the corresponding protruding extension  52   a ,  52   b  or  52   c  of the strain relief element  50 , and more exactly its protruding portion. 
     The strain relief element  50  according to the second embodiment is identical to the strain relief element  30  according to the first embodiment, except for the form (or design) of its protruding extension(s). Each of the protruding extension(s) of the first and second embodiments of the strain relief element allows coupling the strain relief element to the wall and retaining the strain relief element coupled to the wall. 
     According to the second embodiment of the strain relief element  50 , each of the three protruding extensions  52   a ,  52   b  and  52   c  (not visible on  FIG.  6   ) forms a lug. The lug is used for coupling the strain relief element  50  to the wall  101  and retaining the strain relief element  50  coupled to the wall  101 . 
     Two protruding extensions  52   a  and  52   b  prolong pillars  51   a  and  51   b  respectively that border the slot  36 . 
     Each of the protruding extensions  52   a ,  52   b  and  52   c  allows attaching the strain relief element  50  to the wall  101  during a coupling of the strain relief element  50  with a corresponding coupling/decoupling recess  152   a ,  152   b  and  152   c  respectively comprised within the wall  101  or another wall that is possibly comprised in the casing that comprises the wall  101 . 
       FIG.  7    shows schematically, in a bottom and lateral view, the wall  101 , and the assembly  200  for sealing a juncture of the cable  20  in the wall  101 , by using the strain relief element  50 . 
     Prior to connecting the cable  20  to the wall  101 , the user firstly installs, e.g., with one hand, the gasket  28  around the cable end  24  that is held with e.g., another hand. 
     The gasket  28 , when used, and the strain relief element  50  are preferably, each, e.g., outside the casing that includes the wall  101 . 
     After the user has installed the gasket  28  around the cable end  24 , the user inserts the cable end  24  into the aperture  104  by holding with fingers the gripping area  21  and pushing the cable  20  toward the wall  101 . Such a cable end insertion is e.g., used for connecting the connector  26  to another connector (not visible). 
     Once the cable end  24  is inserted in the aperture  104 , the gasket  28  is blocked, at the recess  150 , between the front face of the wall  101  and the flange  22 . 
     The user inserts, in a first insertion direction  60 , the two protruding extensions  52   a  and  52   b  in the corresponding coupling/decoupling recesses  152   a  and  152   b  (not visible on  FIG.  7   ) of the wall  101 , so as to retain the strain relief element  50  at its upper side. 
     Then, the user inserts, in a second insertion direction  62 , the third protruding extension  52   c  in a corresponding coupling/decoupling recess  152   c  of the wall  101  until the third protruding extension  52   c  is locked in a coupling/decoupling recess  152   d  comprised possibly in another wall comprised preferably in the casing. Thus, the strain relief element  50  is attached and coupled to the wall  10   
     Each of the protruding extensions  52   a ,  52   b  and  52   c  allows, on one hand, coupling the strain relief element  50  to the wall  101  and, on another hand, retaining the strain relief element  50  coupled to the wall  101 . 
     To unplug or unconnect the cable  20  from the wall  101  or the casing, the user firstly pushes, in the coupling/decoupling recess  152   d , with a pen, a screwdriver or the like, the third protruding extension  52   c , so as to unlock the third protruding extension  52   c  from the coupling/decoupling recess  152   d  and remove, in a direction opposite to the second insertion direction  62 , the third protruding extension  52   c  from the coupling/decoupling recess  152   c . 
     The user removes, in a direction opposite to the first insertion direction  60 , the protruding extensions  52   a  and  52   b  from the corresponding coupling/decoupling recesses  152   a  and  152   b  of the wall  101  by pulling with e.g., a finger, on the beam  31  c of the slot  36  until the strain relief element  50  is released from the wall  101 . 
     The strain relief element  50  is thus decoupled and detached from the wall  101 . 
     Then, the user takes the cable end  24  away from the aperture  104  by holding with fingers the gripping area  21  and pulling the cable  20  from the wall  101 . 
     The user may remove the gasket  28  from the cable end  24 , so as to disassemble the assembly  200 . 
       FIG.  8    shows schematically from a rear view the cable end  24  inserted in the wall  101  with a cross-section line A-A. 
     The cross-section line A-A vertically crosses the cable  20  along its diameter and the slot  36  at the middle row. 
     The strain relief element  50  is configured, once in a position to cooperate with wall  101  and the flange  22 , to press, directly or indirectly, the flange  22  against the wall  101  when the connector  26  is coupled while the strain relief element  50  remains attached to the wall  101 . 
     Thus, the flange  22  surrounds, directly or indirectly, the aperture  104  and prevents, directly or indirectly, any foreign matter, such as dust and/or water, from passing the juncture of the cable  20  at the aperture  104 . 
     The strain relief element  50  presses the lateral sides of the flange  22  through the pillars  34   a  and  34   b  (hidden on  FIG.  8   ) which extend respectively the pillars  51   a  and  51   b  which border the slot  36 . 
     The aperture  104  is almost closed with the cable end  24  provided with the flange  22  that seals, through either the gasket  28 , as an external elastic element in a first embodiment that is further described infra, or an elastic (or elastomeric) portion of the flange  22 , as an internal elastic element, thanks to the strain relief element  50 . 
     Once positioned to cooperate with the wall  101  and the flange  22 , the rear face  51  of the strain relief element  50  may be completely integrated in the wall  101 , i.e. no part of the strain relief element  50  protrudes from the wall  101 . 
     The strain relief element  50  is coupled to the wall  101  that may be comprised within a casing. 
     The recess  150  and the strain relief element  50  are preferably designed in a complementary way, so that, once the strain relief element  50  is in position of cooperation with the recess  150 , the form of the strain relief element  50  is substantially integrated within the form of the wall  101 . Thus, the external face  51  of the strain relief element  50  does not protrude from the external face of the wall  101 . 
       FIG.  9    shows schematically, along the cross-section line A-A, the cable end  24  inserted in the wall  101 , the gasket  28  pressed by the flange  22  and the strain relief element  50  that presses the flange  22 . 
     The two protruding extensions  52   b  and  52   a  (not visible on  FIG.  9   ) are lodged in their corresponding coupling/decoupling recesses  152   b  and  152   a  (not visible on  FIG.  9   ) of the wall  101 , so as to retain the strain relief element  50  at its upper side. 
     The third protruding extension  52   c  is engaged in the coupling/decoupling recess  152   c  of the wall  101  while emerging from the coupling/decoupling recess  152   d , so as to be accessible from the outside of the wall  101 . 
     The strain relief element  50  presses the flange  22  and an elastic element, namely the gasket  28 , as an external elastic element, or an elastic part of the flange  22 , as an internal elastic (or elastomeric) element (not represented), together against the wall  101  when the connector  26  is coupled while the strain relief element  50  remains attached to the wall  101 . 
     According to the alternative embodiment, the strain relief element  50  presses the flange  22  and the flange elastic part, so that the strain relief element  50  presses the flange  22  and the flange elastic part together against the wall  101  when the connector  26  is coupled while the strain relief element  50  remains attached to the wall  101 . 
     The pillar  34   a  (represented with a non-hatched area) and the pillar  34   b  (not visible on  FIG.  9   ) of the strain relief element  50  (represented with a second hatched area) exert, each, a pressure force, in a pressure direction  80 , on the flange  22  toward the wall  101 . 
     The flange  22  exerts, in turn, the same pressure force, in the pressure direction  80 , on the gasket  28  (represented with a third hatched area) toward the wall  101 . 
     The gasket  28  which is blocked or stopped, on one side, by the rear face of the wall  101  and pushed, on another side, through the front face of the flange  22 , by the pillars  34   a  and  34   b  of the strain relief element  50 , deforms elastically. 
     The gasket  28 , as an external elastic element, is thus compressed against the wall  101  and surrounds the aperture  104 . The gasket  28  seals the juncture of the cable  20  in the wall  101 . 
     In reaction to the pressure force exerted on the stopped gasket  28  by the flange  22 , the gasket  28  exerts a reaction force toward the flange  22 , in a direction opposite to the pressure direction  80 , as a reaction direction  90 . 
     The three protruding extensions  52   a ,  52   b  and  52   c  are coupled to the wall  101  and allow retaining the strain relief element  50  coupled to the wall  101  despite the presence of the reaction force. 
     The invention solution allows using notably a standard and cheap connector to a PCB. 
     The invention solution allows keeping the electronic architecture without modifying it, when present in the appliance. 
     The invention solution uses a strain relief element(s) that is(are) simple and cheap to manufacture. 
     The invention solution uses an assembly that allows sealing a juncture of a cable in a wall while avoiding any passage of foreign matter through a wall aperture.