DE4342820A1 - Two-part electrical connector with short-circuit spring - Google Patents

Abstract

The connector has cooperating plug and socket halves, with a short-circuit spring (18) located between the two socket sleeves for the contact pins in the insulating housing (6) of the socket half, for providing a short circuit between the reception sleeves (14b). The spring can be displaced form the short-circuit position via a control cam element upon assembly of the connector halves, with automatic return into the short-circuit position upon removal of the control cam element.The short-circuit spring contacts the reception sleeves via openings (4b) in the housing, with a gold plate contact surface.

Description

The present invention relates to two part electrical connector with a short lockable, according to the preamble of claim ches 1, as well as a shorting spring for a sol Chen connector, according to the preamble of claim 8. The invention is more specific, however not exclusively with such a connector Use as protection against accidental ignition that of an electric detonator for inflation Airbag of a motor vehicle.

In an automotive air bag inflation system are arranged in the front part of the motor vehicle Impact sensors with the detonators of airbags connected to the front seats of the vehicle. Such Detonator can by a two-part electrical connectors are connected to the ignition voltage, the parts of this connector being separated can be to remove the airbag and / or the detonator of the same z. B. for exchange test to enable purposes. Im disconnected or even in a partially disconnected state of the two-part There is a risk that the detonator, which is necessarily very sensitive, unbeab is operated, so that the airbag unbe is deliberately inflated. This can e.g. B. as  Result of leakage currents or other stray currents or unintentionally supplied currents occur, through which the ignition current supply lines of the Detonator z. B. by electromagnetic induction be excited.

To avoid the risk described above GB-A 2 245 775 discloses a two-part electr trical connector with a receiving part and a Pin carrier part for connection to this, the Receiving part an insulating housing, the first and second spaced-apart, parallel through hollow spaces defined, each of which has a pin holder concludes, and one between the cavities Has short-circuit spring, which is a normal first Po sition in which their contact surfaces at the connectors attack and there is an electrical short circuit between manufacture, as well as a relocated second Has position in which the contact surfaces are not on are gripped by the connectors, and being the pin Carrier part an insulating member, from the pins to Ver binding with the receptacle connections when connecting the both connector parts stand out as well as a tax surface element has to grip the short closing spring for moving them from their first in their second position when the connector parts are at least partially connected to each other, wherein the short-circuit spring when pulling away the control surfaces elements from the short-circuit spring from their second Springs back into its first position.

In this known two-part connector the shorting spring, which is characterized by stamping and molding is formed from a single piece of sheet metal material a pair of wings standing away, the free ones Ends of the wings in the first position of the short  Attack the closing spring on the connections. Both Contact surfaces of the wings are more necessary wise around shear surfaces that are very narrow and for selective plating with a corrosion resistant Digen, electrically very conductive material, such as. B. Gold, are unsuitable.

To overcome this disadvantage, one draws two-part electrical connector according to the Erfin by contacting each other Connector protrudes through an opening in the housing, to make electrical contact with a respective con tact area on the one in the first position To produce shorting spring, the insulating Control element between the elevations and the Contact surfaces is slidable; and through relatively displaceable and in each other Accessible facilities on the Kurz closing spring and on the control surface element for loading distance of the contact surfaces from the control surfaces element during its engagement with the short circuit feather.

Due to the present invention, the short closing spring on relatively wide contact surfaces have the z. B. are plated with gold, since the plat due to a point contact with the Elevations at the connections not by an on handle damaged with the control surface element can.

According to another aspect, the present creates Invention a short-circuit spring, as in the saying 8 is defined.  

Preferred developments of the invention result from the subclaims.

The invention and developments of the invention will in the following based on the graphic representations of an embodiment explained in more detail. In the Drawings show:

Fig. 1 is a longitudinal sectional view of a female electrical connector part of a two-part electrical connector according to an exemplary embodiment of the invention;

Fig. 2 is a fragmentary, seen from below plan view of an insulating housing of the receiving connector part, connections and further details of which are shown schematically in dashed lines;

Fig. 3 is a front view of the female connector with a shorting spring thereof removed;

Figure 4 is a plan view seen from above of an electrical connection of the receiving connec derteil in an uncrimped state and before the attachment of a protective Metallab cover on this.

Figure 5 is a seen from the bottom plan view of the short circuiting spring.

Fig. 6 is an end view of the shorting spring in Rich direction of the arrow 6 in Fig. 5;

Fig. 7 is a longitudinal sectional view of the shorting spring along lines 7-7 of Fig. 6;

Fig. 8 is a top plan view seen in the short-circuiting spring, with portions broken away;

Fig. 9 is a front view of a pin-base, plug-like electrical connector part of the two-part connector;

Figure 10 is a view taken along line 10-10 of Figure 9; and

Fig. 11 is a longitudinal sectional view showing the male and female connector partially in a partially connected NEN state.

A two-part electrical connector for arrangement in the ignition line of an electrical detonator (not shown), which can be actuated to inflate an airbag in an airbag system of a motor vehicle, comprises a female connector part or receiving connector part and a plug-type connector part or connector part 2 or 4 that can be connected to each other. As will be explained below, the connector parts 2 and 4 in their fully constantly connected state serve to arm the primer, ie to connect it to the ignition voltage, while the connector parts in their non-connected or only partially connected state serve to short-circuit that part of the ignition cable which extends away from the detonator. This short-circuiting option is necessary because when the connector parts 2 and 4 have been separated, for. B. if the detonator is to be exchanged or tested, the detonator, which is necessarily very sensitive to the voltages applied to it, could inadvertently be ignited in the absence of the short-circuiting device, for. B. by electromagnetic induction in the device extending from the detonator Zündlei device.

The female connector part 2 will now be described in detail with special reference to FIGS . 1 to 8. The connector part 2 comprises an Isolierge housing 6 with an upper and a lower row of continuous connection receiving cavities 8 a to 8 f, each opening into a front connector side 10 and a rear connection receiving side of the housing 6 . In the cavities 8 a to 8 f each electrical receiving connections 14 a to 14 f are added. A front cavity 16 in the housing 6 , which opens into the connector side 10 , receives a short-circuiting spring 18 to short-circuit the connections 14 b and 14 c in the manner described below. An additional retaining strip 20 is provided to ensure that the connections 14 a to 14 f cannot move back out of their respective cavities under the influence of vibration.

The four cavities 8 a to 8 b of the upper row of cavities are constantly spaced apart in the longitudinal direction of the row, while the two cavities 8 e and 8 f of the lower row are arranged on opposite sides of the spring receiving cavity 16 . The cavity has a front portion 22 of rectangular cross-section with an upper wall 24 , a bottom wall 26 and opposite side walls 28 , as best seen in FIG. 3. As can be seen in FIG. 3, a guide channel 30 provided over the upper wall 24 communicates a rectangular cross section with the cavity 16 via a channel 31 of smaller cross-section, both channels 30 and 31 opening into the connector side 10 . The channels 30 and 31 extend between the cavities 8 b and 8 c to the rear through the housing 6 , essentially to the rear end wall 32 of the cavity 16 . A near the bottom wall 26 provided bar 34 protrudes from the end wall 32 to the front and has a front contact surface 36 for limiting the insertion of the short-circuiting spring 18 into its cavity 16 , as will be described below. From each side wall 28 protrudes within the part 22 of the cavity 16 a rib 37 with a rectangular cross-section and a beveled front end 39 away, which defines a short-circuit spring guide groove 38 in cooperation with the bottom wall 26 . The bottom wall 26 is formed with a rectangular through opening 40 , which is spaced rearward from the plug connection side 10 and is arranged at a distance between the guide grooves 38 . The through opening 40 has a front locking end 42 . The obe re wall 24 of the cavity 16 is formed rearward of the through opening 40 with through slots 46 and 48 which communicate with the terminal receiving cavities 8 b and 8 c and extend in the longitudinal direction of the housing 6 . The two through slots 46 and 48 can be seen in FIG. 2. A continuous front, beveled insertion edge 49 , which is formed in the connector side 10 , surrounds the cavity 16 and the guide channels 30 and 31st Each of the terminal receiving cavities 8 a to 8 f has a rear seal receiving part 50 , a central wire sleeve receiving part 52 and a front book sen area receiving part 54 .

The shorting spring 18 will now be described with special reference to FIGS . 1 and 5 to 8. The short-circuit spring 18 formed by stamping and molding from a single piece of Fe dermetallmaterials sits a base plate 56 which is connected by a front bending region 58 to a rearwardly extending upper plate 60 which is bent upwards through the bending region 58 via the plate 56 is spaced. From the rear end of the plate 56 protrudes at a right angle to this an overvoltage relief plate 62 upwards, which is spaced apart from the bottom plate 56 by a contact surface 64 . A pair of spaced retention elevations 56 are formed in each side edge region 68 of the plate 56 and protrude convexly from there. Between the edge areas 68 of the plate 56 , a retaining tongue 70 is extended out of the plate 56 and projects below it to the rear and ends in a locking end surface 72 . The upper plate 60 has a front portion 61 which extends over the entire width of the Biegungsbe area 58 and the plate 56 . Backward from its front portion 61 , the top plate 60 is bifurcated to create a pair of coplanar spring contact arms 74 and 76 that extend rearward over the relief plate 62 . Each con tact arm 74 and 76 has a rectilinear front section 78 which extends from section 61 to the rear and how section 61 runs at an angle of approximately 20 ° in the direction of plate 56 away. A central section 80 extends from the section 78 to the rear and is angled with respect to the sen at an angle of approximately 25 ° in the direction away from the plate 58 . A contact section 82 extends rearward from section 80 and is angled with respect to it by an angle of approximately 18 ° in the direction away from plate 58 . The contact section 82 extends substantially parallel to the base plate 56 . A rear end portion 84 protrudes from the contact portion 82 and is angled downward in relation to this at an angle of approximately 30 °. The contact portion 82 of each spring arm 74 and 76 has a transversely centrally arranged surface 86 on its top, the contact surface 86 selectively with corrosion-resistant material such as. B. gold, is plated with high electrical conductivity. Each lateral edge region of each spring arm 74 and 76 is formed with an upwardly curved, protruding elevation 88 which extends over the connection point between the spring arm sections 82 and 84 at the rear end of the respective contact surface 86 , which thus extends between the elevations 88 located. The contact surfaces 86 are best seen in FIG. 8.

The connections 14 b and 14 c, which are identical to one another, will now be described with special reference to FIGS. 1 and 4, in which the connections 14 b are shown in detail. As shown in Fig. 4, in which the connection 14 b is shown in an uncrimped state, each connection 14 b and 14 c has a pin receiving area 90 with pin engagement contact springs 92 , a central area 94 , an open wire sleeve 96 and an open one Insulation sleeve 98 with a pair of longitudinally offset, highest standing extensions 100 . The central region 94 is formed with a centrally located contact elevation 102 which projects convexly beneath the base 104 of the central region 194 . As shown in Fig. 1, a protective metal cover 106 is attached to the receiving area 90 around by means of brackets 108 to the cover 106 of the same to the central area 94 around between upstanding ears 110 and the receiving portion 90 are clamped. The cover 106 has a locking tongue 111 projecting to the rear.

Before being inserted into a cavity 8 b or 8 c, as is the case, the wire sleeve 96 of each connection is crimped onto the stripped metal core of a respective insulated signal line, which extends away from the detonator of the airbag, the insulating sleeve 98 is crimped around a bung seal 112 which encloses the insulation of the signal line. As shown in Fig. 2, the signal line 14 b is crimped onto a signal line L1 and the terminal 14 c is crimped onto a signal line L2.

The connections 14 a and 14 d to 14 f may be identical to the connections 14 b and 14 c, but are not provided with contact bumps 102 . These connections are curved to other lines, not shown, for. B. on lines that are to be electrically connected to a diagnostic connector that is assigned to the air bag system of the motor vehicle.

The female connector part 4 , which is a pin socket connector, will now be described with specific reference to FIGS. 9 and 10. The connector part 4 has an insulating housing 114 with a front connector side 116 and a rear side 118 . An upper and a lower row of parallel electrical pins 120 a to 120 f extend through the housing 114 . Each pin has a connector area 122 that protrudes from the connector side 116 and a lead termination area 123 that protrudes from the rear 118 . One of the line terminal regions 123 is shown in FIG. 10. The four pins 120 a to 120 d of the upper row are evenly spaced apart, with the same distance as the cavities 8 a to 8 d of the housing 6 Ge, and the two pins 120 e and 120 f of the lower row are the same Spacing as the cavities 8 e and 8 f of the housing 6 stands apart from each other. A short-circuit spring control surface strip 124 protrudes from the connector side 116 below half of the pins 120 b and 120 c and is surmounted by a central guide rib 126 with a T-shaped cross section. The control surface bar 124 extends parallel to the rows of pins and is located between the pins 120 b and 120 c. The guide rib 126 protrudes b midway between the pins 120 and 120 c to the top. From the control surface bar 124 extends in the middle of its width in the manner shown in FIG. 10, a downwardly tapering front control surface projection 128 with a frustoconical cross-section, which has a beveled front control surface 132 . The control surface bar 124 has a front nose 122 with a front control surface 130 that is substantially coplanar with the control surface 132 . On the underside of the nose 129 there are two protruding ribs 134 on both sides of the projection 128 , which extend backwards from the front control surface 130 of the nose 129 . Control surfaces 136 which run obliquely downwards at the rear on the underside of the control surface strip 124 are arranged on both sides of the control surface projection 128 . Each control surface 136 extends rearward from the shoulder 138 , which is substantially aligned with the tip of a respective pin 120 b or 120 c, to a planar bottom surface 137 , to a planar bottom surface 137 of the control surface strip 124 . The guide rib 126 he extends from the front of the control surface bar 124 to the rear to the housing 114 and be sits a chamfered or chamfered front end 140th The control surface bar 124 has a flat upper surface 141 .

The pins 120 b, and c 120 are crimped in the in FIGS. 10 and 11 as shown, on signal lines L3 and L4, respectively, which extend from a Zündstromquelle for the airbag squib. Alternatively, the pins 120 b and 120 c can be soldered to corresponding signal conductors on a circuit board (not shown). The pins 120 a and 120 b to 120 f can be crimped onto other lines (not shown) or soldered to other conductors on a circuit board which z. B. stretch away from a diagnostic connector.

The assembly of the shorting spring 18 and the connections 14 a to 14 e on the housing 6 will now be described with particular reference to FIGS. 1 and 3. The short-circuiting spring 18 is inserted with the rear end section 84 forward and uppermost in its cavity 16 , so that the edge regions 68 of the base plate 56 are guided through the beveled surfaces 39 of the ribs 37 in the grooves 38 between the ribs 37 and the bottom wall 26 of the cavity part 22 are recorded, the elevations 66 engaging in a resilient manner on the ribs 37 . The short-circuiting spring 18 is so far advanced into place until their retaining tongue 70 in the through hole 40 in the bottom wall 26 so that the contact surface 72 of the tongue 70 opposite the INTERLOCKS development end 42 of the through hole 40th The forward movement of the short-circuiting spring 18 is limited by the engagement of the overvoltage relief plate 62 on the contact surface 36 of the strip 34 . The resilient engagement of the elevations 66 on the ribs 37 serves to press the bottom plate 56 of the short-circuiting spring 18 down against the bottom wall 26 of the cavity region 22 . When the shorting spring reaches its fully inserted position in the cavity 16 , the sections 82 and 84 of the spring arms 74 and 76 of the shorting spring 18 , after they have never been depressed by the top wall 24 of the cavity 16, return spring movement through the slots 46 or 48 , whereby they enter the cavities 14 b or 14 c, as shown in Fig. 1 in dashed lines.

To populate the housing 6 with the connections, each cavity is inserted with the socket area of the connection first into its cavity until the locking tongue 111 of the cover 106 engages in a locking manner on a shoulder in the cavity part 54 . When the connections 14 b and 14 c are introduced into the cavities 8 b and 8 c, the elevations 102 of the connections enter the slots 46 and 48 and thereby drive the spring arms 74 and 76 into the position shown in solid lines in FIG. 1 nach un th. In this position, each elevation 102 engages the contact surface 86 of the respective arm 74 or 76 , whereby the lines L1 and L2 are short-circuited via the connections and the short-circuiting spring 18 , so that the airbag detonator connected to these lines not inadvertently e.g. B. is ignited by unwanted voltages in the lines L1 and L2 induced te. When the connectors are in place in their cavity, the set retaining strip 20 is mounted on the housing 6 to thereby ensure that the connectors cannot move back out of their respective cavities by vibration, e.g. B. in cases where the connector part 2 is used in a motor vehicle.

To arm the airbag detonator, the connector part 4 is connected to the connector part 2 , as will be described in the following with special reference to FIGS. 3 and 9 to 11. To connect the connector parts 2 and 4 , the connector part 4 is moved in the direction of arrow A in FIG. 11 toward the connector part, so that the control surface strip 124 enters the cavity area 122 and the pins 120 a to 120 f each in the cavities 8 a and 8 f of the Ge enter and connect with the respective socket areas 90 of the connections. The control surface bar 120 is guided into the cavity 22 , namely by inserting the guide rib 140 of the connector part 2 into the guide channel 30 of the housing 6 with the aid of the beveled surfaces 49 and 140 , where when the control surface bar 124 is raised above the bottom wall 20 of the cavity area 82 due to the interlocking T-shaped cross sections of the guide rib 140 and the guide channel 30 is fixed. At the beginning, the control surface 132 of the jump 128 of the control surface bar 124 presses down the section 61 of the upper plate 60 of the short-circuiting spring 18 , after which the planar bottom surface 137 of the control surface bar 124 moves the sections 78 of the spring arms 74 and 76 along, the projection 128 is received between arms 74 and 76 . The control surface 130 of the nose 129 then engages the sections 80 of the spring arms 74 and 76 and thereby presses them down so that the contact sections 82 of the spring arms are moved away from the contact elevations 102 of the connections, after which the nose 129 then moves between the Arranges elevations 102 and the sections 82 , each rib 134 of the control surface bar 124 executes a sliding movement along a respective elevation 88 of the spring arms 74 and 76 , whereby the contact surfaces 86 of the spring arms are spaced from the underside of the control surface bar 124 . The contact surfaces 86 are thus not damaged by contact with the underside of the control surface bar 124 be. The connector part 4 is moved in the direction of arrow A until the connector side 116 of the connector part 4 abuts the connector side 10 of the connector part 2 . Towards the end of this connection process, the control surfaces 136 of the control surface strip 124 engage the central sections 80 of the spring arms 74 and 76 , whereby the spring arms are driven down to an extent that is limited by the contact surface 64 of the overvoltage relief plate 62 , thereby avoiding over-stretching or over-stretching of the arms 74 and 76 .

It is understood that the contact surfaces 86 of the con tact sections 82 are not moved away from the elevations 102 until the pins 120 b and 120 c have been moved sufficiently far into the receiving areas 90 of the connections 14 b and 14 c, respectively, by one to make good electrical contact with them. Likewise, when the connector parts 2 and 4 are disconnected to disarm the airbag detonator, there is no damage to the contact surfaces 86 by pulling back the control surface strip 124 , and the elevations 102 engage the respective contact surfaces 86 in good time before the pins 120 b and 120 are separated c from the socket areas 90 on.

Claims (10)

1. Two-part electrical connector ( 2 , 4 ) with egg nem part ( 2 ) and a pin carrier part ( 4 ) for connection to this, the part ( 2 ) an insulating housing ( 6 ), the first and second spaced, parallel through cavities ( 8 b, 8 c), each of which receives a pin receiving connection ( 14 b, 14 c), and between the cavities ( 8 b, 8 c) has a short-circuiting spring ( 18 ) which has a normal first position in which its contact surfaces ( 86 ) on the connections ( 14 b, 14 c) and establish an electrical short-circuit path therebetween, such as has a shifted second position, in which contact surfaces ( 86 ) are disengaged from the connections ( 14 b, 14 c), and wherein the pin carrier part ( 4 ) an insulating member ( 114 ), of the pins ( 120 ) for connec tion with the receiving connections ( 14 b, 14 c) when connecting the two connector parts ( 2 , 4 ), and a control surface element ent ( 124 ) has to engage the short-circuit spring ( 18 ) to move it from its first to its second position when the connector parts ( 2 , 4 ) are at least partially connected to one another, the short-circuit spring ( 18 ) when the control surfaces are pulled away springs back from the short-circuit spring ( 18 ) from its second position to its first position, characterized by
a contact elevation ( 102 ) which projects from each connection ( 14 b, 14 c) or from the short-circuiting spring ( 18 ) through an opening ( 46 , 48 ) in the housing ( 6 ) in order to make electrical contact with a respective contact surface ( 86 ) on the located in the first position union spring ( 18 ) or with the connections ( 18 b, 18 c), the insulating control surface element ( 124 ) between the elevations ( 102 ) and the contact surfaces ( 86 ) slidably is; and through
Devices ( 88 , 34 ) on the short-circuiting spring ( 18 ) and on the control surface element ( 124 ), which can be displaced relative to one another and can be brought into engagement, for spacing the contact surfaces ( 86 ) from the control surface element ( 124 ) during their engagement with the short-circuiting spring ( 18 ). 2. Connector according to claim 1, characterized in that the short-circuiting spring ( 18 ) has a projecting elevation ( 88 ) on each side of each contact surface ( 86 ) thereof and the control surface element ( 124 ) has a projecting rib ( 134 ) for sliding engagement with each of the above elevations ( 88 ). 3. Connector according to claim 1 or 2, characterized in that the in a cavity ( 16 ) in the housing ( 6 ) received short-circuit spring ( 18 ) on a bottom wall ( 26 ) of the cavity ( 16 ) attached base plate ( 56 ) and an upper plate ( 60 ) which is resiliently connected to the bottom plate ( 56 ) and which can be depressed by the control surface element ( 124 ), the contact surfaces ( 86 ) being provided on the upper surface of the upper plate ( 60 ) . 4. Connector according to claim 3, characterized in that the control surface element ( 124 ) has a first, a second and a third control surface ( 130 , 132 , 136 ) for successive engagement with the upper plate ( 60 ), in order to increase this downwards in the direction of an overvoltage discharge plate ( 62 ), which protrudes from the bottom plate ( 56 ) of the short-circuiting spring ( 18 ). 5. Connector according to claim 3 or 4, characterized in that the upper plate ( 60 ) is forked ausgebil det and defines a pair of spring arms ( 74 , 76 ), each of which has a flat portion ( 82 ) on which a respective contact surface ( 86 ) is provided. 6. Connector according to one of claims 1 to 5, characterized in that the control surface element ( 124 ) has a flat surface for engaging the contact elevations ( 102 ) and underneath a downwardly extending projection ( 128 ) for arrangement between the spring arms ( 74 , 76 ), wherein the slidably engaging means ( 134 ) of the control surface member ( 124 ) is located between the flat upper surface and the projection ( 128 ). 7. Connector according to one of claims 3 to 6, characterized in that lateral edge regions ( 68 ) of the base plate ( 56 ) are slidably arranged in respective grooves ( 38 ) in side walls ( 28 ) of the cavity ( 16 ), with retaining projections ( 66 ) on the bottom plate ( 56 ) in a resilient manner on the upper walls ( 37 ) of the grooves ( 38 ) to press the bottom plate ( 56 ) against the bottom wall ( 26 ) of the cavity ( 16 ). 8. Short-circuiting spring ( 18 ) for an electrical connector according to one of claims 1 to 7, characterized by a base plate ( 56 ), an upper plate ( 60 ) and a bend region ( 60 ) connecting the upper plate ( 60 ) to the base plate ( 56 ). 58 ), wherein the upper plate ( 60 ) extends over the bottom plate ( 56 ) and is angled in the direction away therefrom, the upper plate ( 60 ) having a first region ( 61 ) connected to the bending region ( 58 ) and a A pair of juxtaposed spring arms ( 74 , 76 ) extending from the first portion ( 61 ) of the top plate ( 60 ), the top plate ( 56 ) having a surge relief plate ( 62 ) which is attached to one of the bends supply area ( 58 ) remote end of the base plate ( 56 ), each spring arm ( 74 , 76 ) has a planar section ( 82 ) with a contact surface ( 86 ) on its top and the planar section immediately telbare over the overvoltage relief plate ( 62 ), and wherein each spring arm ( 74 , 76 ) on both sides of the contact surface ( 86 ) of each spring arm ( 74 , 76 ) has protruding elevations ( 88 ) which protrude beyond the contact surface. 9. Short-circuiting spring according to claim 8, characterized by retaining elevations ( 66 ) which are provided on the upper surface of the base plate ( 56 ) at lateral edge regions ( 68 ) of the same in the direction of the upper plate ( 60 ). 10. Short-circuiting spring according to claim 8 or 9, characterized in that the first section ( 61 ) of the upper wall ( 60 ) is angled at an angle of approximately 20 ° in the direction away from the base plate ( 56 ), each planar section ( 82 ) of each spring arm ( 74 , 76 ) with the first section ( 61 ) of the upper wall ( 60 ) through a first, with the first section ( 61 ) of the upper wall ( 60 ) coplanar intermediate section ( 78 ) and through one in one Angle of about 25 ° in the direction from the bottom plate ( 58 ) angled away, second intermediate section ( 80 ) is connected, wherein the planar contact surface support section ( 82 ) with respect to the second, between ordered section ( 80 ) at an angle is angled away from the base plate ( 56 ) by approximately 18 °.