EP3298660B1 - Plugging device comprising a plug pin and a contact sleeve - Google Patents

Description

The invention relates to a plug-in device, comprising a plug pin and a contact sleeve for receiving the plug pin.

Contact sleeves are used for example in sockets or sockets of electrical plug devices for power flow according to DIN VDE 0623, EN 60309 2 ("CEE plug-in devices") or according to IEC 62196 ("E-car charging connectors"). They typically have a substantially circular cylindrical cavity for receiving a correspondingly shaped plug pin. For a good and permanent electrical contact should be the highest possible contact force between the inside of the contact sleeve and the pin exist. On the other hand, this force must not be too large, so that a comfortable insertion and separation of the plug-in device by a user remains possible.

Against this background, it was an object of the present invention to provide a plug-in device with both good contact properties and good handling.

This task is done by a plug-in device according to claim 1 solved. Advantageous embodiments are contained in the subclaims.

• Bohren und/oder Fräsen eines sich entlang einer Steckachse erstreckenden und zum distalen Ende hin verjüngenden Hohlraumes in einem Rohmaterial;
• optionales Bohren und/oder Fräsen mindestens einer Vertiefung in der dem Hohlraum zugewandten Innenseite mindestens eines Kontaktfingers;
• Einbringen von in Richtung der Steckachse verlaufenden Schlitzen zur Freistellung von Kontaktfingern um den Hohlraum herum.

There is also disclosed an unclaimed method of making a contact sleeve. The contact sleeve in this case has a cavity extending in the direction of a plug-in shaft for receiving an associated plug pin in an electrical plug-in device, and contains at least two contact fingers, which are arranged parallel to each other around the cavity, wherein the contact fingers under extension of the plug pin Move cavity elastically apart. The method comprises the steps (which may be carried out in the indicated or another suitable order or simultaneously):

• Drilling and / or milling a cavity extending along a plug-in axis and tapering towards the distal end in a raw material;
• optionally drilling and / or milling at least one depression in the inner side of at least one contact finger facing the cavity;
• Introducing slots extending in the direction of the plug-in axis to release contact fingers around the cavity.

With the method, contact sleeves can be produced, which are described in more detail below.

• Mindestens zwei Stege, Zungen oder Finger, welche im Folgenden als "Kontaktfinger" bezeichnet werden und welche parallel zueinander um den Hohlraum herum angeordnet sind und den Hohlraum dadurch begrenzen bzw. definieren, wobei sich die Kontaktfinger beim Einstecken des Steckerstiftes unter Erweiterung des Hohlraumes elastisch auseinander bewegen können. Vorzugsweise sind alle Kontaktfinger gleichartig ausgebildet, sie können jedoch auch verschieden sein.
• Mindestens eine Vertiefung, die in der dem Hohlraum zugewandten Innenseite mindestens eines Kontaktfingers ausgebildet ist. Vorzugsweise befindet sich eine derartige Vertiefung in jedem der vorhandenen Kontaktfinger. Weiterhin sind vorteilhafterweise mehrere Vertiefungen an verschiedenen Kontaktfingern so angeordnet, dass sie ineinander übergehen und somit eine sich über zwei oder mehr Kontaktfinger hinweg erstreckende Gesamtvertiefung ergeben.

According to the invention, the plug-in device comprises a plug pin and a contact sleeve with a cavity for receiving the associated plug pin. The cavity should thereby extend in the direction of a predetermined axis, which is referred to below as "plug-in axis", since the plug pin moves during insertion along this axis. Furthermore, the "associated" connector pin should be a predetermined connector pin to which the dimensions of the cavity are matched. Typically, the pin is circular cylindrical with a given Cylinder diameter between 1 mm and 15 mm. The contact sleeve contains the following components:

• At least two webs, tongues or fingers, which are referred to below as "contact fingers" and which are arranged parallel to each other around the cavity and thereby define or define the cavity, wherein the contact fingers when inserting the connector pin under extension of the cavity apart elastically can move. Preferably, all contact fingers are the same design, but they can also be different.
• At least one recess, which is formed in the cavity facing the inside of at least one contact finger. Preferably, such a depression is located in each of the existing contact fingers. Furthermore, advantageously, a plurality of depressions are arranged on different contact fingers such that they merge into one another and thus result in a total recess extending over two or more contact fingers.

The contact sleeve described ensures a comfortable insertion while mechanically secure receiving a pin and a reliable electrical contact, since the pin is received under the elastic contact pressure of the contact fingers in the cavity of the contact sleeve. The at least one depression on an inner side of the contact fingers supports these properties in that there is no contact between the plug pin and the contact sleeve in the region of the depression.

The freestanding contact fingers preferably produce the desired contact pressure solely on account of their elastic properties. Optionally, however, the compressive force exerted by the contact fingers on a connector pin can also be achieved, reduced, or assisted by other means. For example, a higher contact pressure can be generated by the contact fingers are surrounded on the outside by an elastic spring ring. The advantages of the invention are already achieved by providing a single recess in a single contact finger. An optimization of the advantages, however, usually occurs when seen in the direction of the thru axle two or more wells are arranged one behind the other, wherein between the wells contact surfaces for contacting a plugged into the cavity plug pin lie. If, in the following, "the depression" will be discussed, it should always be understood that the corresponding properties should be given for at least one of several depressions, preferably for all existing depressions.

According to the invention, the recess with the contact surface on the inside of the contact finger forms an edge angle of less than 100 ° (measured in the material of the contact finger), preferably of less than about 91 °. The "contact surface" is intended to be that surface on the inside of the contact finger, which comes into contact with the plug pin when a plug pin is inserted. The explained feature means that the recess is at least locally sharp-edged. Of course, the edge angle of the recess may also be significantly sharper than the mentioned degrees, with angles of less than 90 °, as a rule, are difficult to produce.

The edges, which forms the depression with the contact surface, can all be of the same kind (that is, for example, all sharp-edged) or differently formed. In particular, the edges passed first when inserting a plug pin may be "soft" and the edges subsequently passed through may be sharp-edged; In this way, the removal of the connector pin runs as low friction. Furthermore, it is preferred if the described (sharp) edge of the recess runs at least in sections transversely to the plug-in axis.

The depression must, so that it can develop its desired effect, of course, lie in a region of the cavity, which receives the plug pin in the assembled state of the plug-in device ("plug-in area"). It is particularly preferred if the depression in the distal Half of the cavity is located, by definition, the "distal" end of the cavity is located at the end of the cavity at which the opening for insertion of a connector pin lies. The depression can lie in particular in the last approximately last 30% of the axial extent of the cavity. In other words, the recess is preferably in the entrance region of the cavity, which ensures that as far as possible the entire length of the plug pin must pass through the depression.

As already explained, the inside of the contact fingers is divided into "contact surface", which contacts a plug pin in the assembled state of the plug-in device, and surface in the region of the depressions, where no contact between the material of the contact fingers and a plug pin takes place. According to a preferred embodiment of the invention, these areas of the recess (s) occupy between about 20% and about 80%, preferably between about 30% and about 70% of the total area of the inside (ie the rest is formed by contact area) ,

In general, the shape of the recess can be arbitrary. Preferably, at least two recesses are provided on different contact fingers, which together form a circumferential groove around the plug-in axis.

Preferably, it is provided that at least one contact finger, seen in a section perpendicular to the plug-in axis, contacts the associated plug pin at (at least) two points, which are separated by a gap between plug pin and contact finger.

By definition, a "gap" should be present if the distance between the plug pin and the contact finger is so great that no electrical current flow takes place (in the case of (network) voltages of usually less than 1000 V occurring in practice). Typically, the gap width is greater than about 0.01 mm. Furthermore, the condition usually refers to an associated pin with a circular cylindrical shape.

The touch of a pin can be done at exactly two points (in a plane perpendicular to the plug axis cutting plane) or along exactly two axially extending lines (composed of the above points). With similar training of all contact fingers, the total number of contact points or contact lines is then equal to twice the number of contact fingers. If there are more than two contact points per contact finger, the total number increases accordingly.

In the contact sleeve, in turn, the contact fingers may be freestanding or optionally coupled with additives such as an outer circumferential elastic spring ring.

The described contacting at two points can be achieved in various ways. For example, three-dimensional structures with depressions and elevations can be applied to the inner surface of the contact finger (eg by milling or embossing). For example, the contact points could be on raised ribs formed on the inner surface of the contact finger. In particular, the contact surface on the inside of at least one contact finger can be truncated cone-shaped or circular-cylindrical, wherein the radius R _F at at least one axial position (preferably at all axial positions in the distal region of the plug-in axis) is smaller than the (nominal) radius R _S the associated connector pin. Typically, the contact surface radius is about 5% to about 20% smaller than the radius of the connector pin (ie, (R _S -R _F ) / R _S = 0.05 to 0.2). For geometrical reasons, in the mentioned differences in size of the radii of the contact fingers can touch the connector pin only at two points (or lines).

According to a further modification of the contact sleeves described above, the inside of at least one contact finger is coated at least on the contact surfaces, for example with a layer of nickel and / or silver. The core material of the contact fingers or the contact sleeve is typically made of a highly electrically conductive and inexpensive material such as brass. Said coating provides on the contact surfaces for improved mechanical and / or electrical properties. In practice, however, it has been found that a coating is removed after prolonged use. In the above-described contact between the contact finger and pin at two points in this regard, an advantageous Vorratsbildung of coating material is achieved: namely, if coating material is removed in the contact points, move the contact points along the gap between them towards each other and remain constantly with not abgener Coating in contact.

It is preferably provided that the cavity tapers towards the distal end, wherein the contact fingers and a contact body carrying the contact fingers of the contact sleeve are made of a raw material without bends.

The taper of the cavity can in particular be such that the cavity is substantially conical (or truncated cone-shaped) with a cone radius increasing from the plug opening to the bottom of the cavity.

In the contact sleeve, in turn, the contact fingers may be free-standing or optionally coupled with additives (e.g., spring washer).

By a material-removing production of a grown material, without bending the material, a contact sleeve can be obtained with improved properties.

According to another embodiment of all the contact sleeves described above, at least one of the contact fingers along its axial extent a variable thickness (measured perpendicular to the plug axis). Typically, all contact fingers have the same thickness variations. By changing the thickness, the stability and the elastic behavior of the contact fingers when inserting a pin can be adjusted as needed. The thickness of the contact fingers can be done by changing the radius or the clear width of the cavity, ie by a suitable shape of the inside of the contact fingers. Additionally or alternatively, radius changes may also be present on the outside of the contact fingers. It is particularly preferred if the contact fingers are made thicker at their proximal end (that is, in the vicinity of the carrier body) than at the opposite distal end.

• Bohren und/oder Fräsen eines sich entlang einer Steckachse erstreckenden und zum distalen Ende hin verjüngenden Hohlraumes in einem (vorzugsweise im Wesentlichen stangenförmigen) Rohmaterial;
• Einbringen von in Richtung der Steckachse verlaufenden Schlitzen zur Freistellung von Kontaktfingern um den Hohlraum herum.

An unclaimed example further relates to a method for producing a contact sleeve having a hollow extending in the direction of a plug-in axis for receiving an associated plug pin in an electrical plug-in device, in particular for producing a contact sleeve according to one of the embodiments described above. The method comprises the following steps:

• Drilling and / or milling a hollow space extending along a plug-in axis and tapering towards the distal end in a (preferably substantially rod-shaped) raw material;
• Introducing slots extending in the direction of the plug-in axis to release contact fingers around the cavity.

Typically, the first step of the method begins with the production of a (circular cylindrical) bore, wherein the radius of this bore is slightly smaller than the radius of the connector pin associated with the contact sleeve (see above). Furthermore, the depth of the bore may optionally be greater than the length required to receive a pin. In a next sub-step can then be widened by milling the radius of the bore at its proximal end, that results in the desired tapered shape of the cavity, in particular a cone shape. By the method, a contact sleeve can be made with in the grown material inwardly inclined contact fingers.

Figur 1

eine perspektivische Ansicht einer Kontakthülse gemäß einer ersten Ausführungsform;

Figur 2

einen Längsschnitt durch die Kontakthülse von Figur 1;

Figur 3

eine Ansicht auf die Vorderseite der Kontakthülse von Figur 1;

Figur 4

eine perspektivische Ansicht einer Kontakthülse gemäß einer zweiten Ausführungsform, die an ihrer Innenseite Vertiefungen trägt;

Figur 5

einen Längsschnitt durch die Kontakthülse von Figur 4;

Figur 6

eine Ansicht auf die Vorderseite der Kontakthülse von Figur 4;

Figur 7

eine Ansicht auf die Rückseite der Kontakthülse von Figur 4;

Figur 8

eine Detailansicht einer Vertiefung der Kontakthülse von Figur 4;

Figur 9

einen Querschnitt entlang der Linie IX-IX von Figur 2 durch den Kontaktbereich zwischen einem Kontaktfinger und einem Steckerstift.

In the following, the invention will be explained in more detail by way of example with the aid of the figures. Showing:

FIG. 1

a perspective view of a contact sleeve according to a first embodiment;

FIG. 2

a longitudinal section through the contact sleeve of FIG. 1 ;

FIG. 3

a view of the front of the contact sleeve of FIG. 1 ;

FIG. 4

a perspective view of a contact sleeve according to a second embodiment, which carries on its inside recesses;

FIG. 5

a longitudinal section through the contact sleeve of FIG. 4 ;

FIG. 6

a view of the front of the contact sleeve of FIG. 4 ;

FIG. 7

a view on the back of the contact sleeve of FIG. 4 ;

FIG. 8

a detailed view of a recess of the contact sleeve of FIG. 4 ;

FIG. 9

a cross section along the line IX-IX of FIG. 2 through the contact area between a contact finger and a pin.

In the FIGS. 1 to 3 an embodiment of a contact sleeve 100 is shown. The contact sleeve 100 is used in a non-illustrated coupling or socket of an electrical plug-in device to make electrical contact with an associated (usually circular cylindrical) pin connector.

The contact sleeve I made of an electrically conductive material, such as a metal such as copper or brass, and has a along a plug axis A extending cavity HR, in which the plug pin can be inserted. The cavity HR is formed by two or more (in the example shown by four) contact fingers 101, which extend parallel to each other and are arranged on a circle around the insertion axis A.

How out FIG. 2 can be seen, the contact fingers 101 are formed so that they surround a plug-in area 105 in the form of a cone or truncated cone, in which comes to rest in the assembled state of the plug-in device of the plug pin. The cone is oriented in such a way that the cavity HR tapers towards the distal end of the contact sleeve (ie towards the insertion opening, in FIG FIG. 2 right). The angle of inclination of the cone is typically between about 0.5 ° and about 3 ° relative to the stub axle A.

The narrowest radius of the cavity HR in the region of the plug-in opening (which preferably has a funnel-shaped extension to the outside, which should facilitate the insertion of a plug pin) is preferably about 10% smaller than the nominal radius of the associated plug pin. When inserting the pin, therefore, the contact fingers 101 must move outward and expand the cavity HR accordingly. This movement takes place under an elastic counterforce, which in turn provides the necessary contact pressure between the contact sleeve and pin.

How out FIG. 2 can be seen further, the cavity HR extends beyond the plug-in area 105 even deeper into the contact sleeve. This lower-lying bottom portion 106 is no longer reached by the pin and only serves to give the contact fingers 101 the desired elastic properties. In this regard, it can be seen that the contact fingers 101 have a variable thickness along their axial extent. In the bottom area 106, they are thicker than in the plug-in area 105, wherein the wall thickness in the plug-in area 105 is uniform, since the outer contour runs conically in accordance with the inside of the contact fingers 101.

The contact fingers 101 are based on a carrier body 107, in which a connection 110 for inserting an electrical connection line (not shown) is located on the side opposite the contact fingers, wherein this line can be fixed by a transverse screw 111.

The production of the contact sleeve 100 is preferably made of a raw material without bending processes. In this case, a first, circular-cylindrical bore with a small radius (R _F , see FIG. FIG. 9 ), wherein this radius typically corresponds to the radius of the bottom region 106 or else may deviate from it by a mere 1/10 mm due to production. Starting from the free space thus created, a conical shape is then incorporated into the plug-in area 105 of the cavity HR by milling. Optionally, furthermore, a corresponding outer cone can be turned on. After completion of the milling of the cavity HR, slits 103 are created by radially extending cuts (along the plug-in area 105 and bottom area 106), which free the desired number of contact fingers 101.

Compared to a manufacturing process in which contact fingers are first released and then bent into a circular cylindrical bore in order to achieve a cone shape, the described method has the advantage of achieving a better elastic behavior by eliminating bends.

Another advantage of the described manufacturing method is described below with the aid of FIG. 9 explained in more detail. As can be seen in the radial section through a contact finger 101 (or 201) and a plug pin S, the contact finger 101 has (in the distal plug-in area 105, the cut runs at the narrowest distal point, ie along the line IX-IX of FIG FIG. 2 ) a cone-shaped (or more precisely truncated cone-shaped) inside with a radius R _F. According to FIG. 2 This is the smallest radius that occurs in the plug-in area 105. For manufacturing reasons, this radius R _{F is} smaller than the nominal radius R _{S of} the associated connector pin S (for example, R _F = 4.50 mm, R _S = 4.97 mm). Due to this difference, the contact finger 101 (seen in radial section) rests only at the ends of the contact surface at two points P1 and P2 on the plug pin surface, these points being separated by a gap SP of typically Δ = 0.12 mm width.

In addition to improved mechanical and electrical contact properties, contact at two points (or lines) per contact finger 101 has a further advantage when the contact surface of the contact fingers is coated (typically) with a metal such as nickel (Ni) and / or silver (Ag) the contact finger made of brass, which is provided with a layer of Ni and above Ag). If, due to friction at the contact points P1 and P2, a material abrasion occurs over time, the contact points migrate towards each other while the gap SP is consumed. This ensures that the contact between the contact finger and the plug pin is constantly made via "fresh" coating material, which is virtually stored in the area of the gap.

The FIGS. 4 to 8 show an embodiment of a contact sleeve 200 according to the invention. The contact sleeve 200 is formed substantially the same as the first contact sleeve 100 of the FIGS. 1 to 3 , wherein corresponding components are provided with reference numerals increased by 100 and need not be re-explained. The contact sleeve 200 has For example, again a cone-shaped cavity HR and is preferably made without bending.

A significant innovation in the second contact sleeve 200 are depressions 202, which are mounted in the distal start region of the cavity HR on the inside of the contact fingers 201. In the example shown, the recesses 202 are formed in particular in the form of four annular circumferential grooves, these grooves are recessed as sharp as possible in the inside of the contact fingers 201.

FIG. 8 shows in this regard in the enlarged view of a recess 202, that the edge of the contact surface KF on the inside of the contact finger 201 forms an edge angle α of typically about 90 °. For example, the depth t of the grooves may be between about 0.2 and about 1 mm (Note: By definition, the pad is to include any point that comes in contact with a pin).

In FIGS. 4 and 5 Furthermore, it can be seen that the contact sleeve 200 in the bottom region 206 has an outer constriction, so that the contact fingers 201 get a desired thickness and thus a desired spring behavior.

While the figures show freestanding contact fingers 101, 201, the contact fingers could optionally also be enclosed on the outside in the distal region (105, 205) by an elastic spring ring (not shown), which increases the radially inwardly directed pressure on an inserted plug pin.

Claims (9)

1. Plugging device comprising a plug pin (S) and a contact sleeve (200) with a cavity (HR) extending in the direction of a insertion axis (A) for receiving the corresponding plug pin (S), containing:

   - at least two contact fingers (201) which are arranged parallel to one another around the cavity (HR), the contact fingers moving elastically apart when the plug pin is inserted, widening the cavity;

   - at least one depression (202) in the inner side facing the cavity (HR) of at least one contact finger (201),

   characterized in that the depression (202) is located in a contact area (KF) at the inner side and forms therewith an edge angle (α) of less than about 100°, wherein the contact area (KF) is that surface at the inner side of the contact finger (201), which comes into contact with the plug pin when inserting the plug pin (S).
2. Plugging device according to claim 1,
   characterized in that the depression (202) forms an edge angle (α) of less than about 91° with the contact area (KF) at the inner side.
3. Plugging device according to at least one of the preceding claims,
   characterized in that the depression (202) is arranged in the distal half of the cavity (HR).
4. Plugging device according to at least one of the preceding claims,
   characterized in that between about 20 % and about 80 %, preferably between about 30 % and about 70 %, of the surface of the inner side of the contact finger (201) are taken up by the depression (202) respectively by the depressions (202).
5. Plugging device according to at least one of the preceding claims,
   characterized in that there are at least two depressions (202) at different contact fingers (201), which form together a circumferential groove around the insertion axis (A).
6. Plugging device according to at least one of the preceding claims,
   characterized in that at least one contact finger (101, 201) seen in a section perpendicular to the insertion axis (A) comes into contact with the corresponding plug pin (S) at two points (P1, P2), which are separated by a gap (SP) between plug pin (S) and contact finger (101, 201).
7. Plugging device according to at least one of the preceding claims,
   characterized in that the contact area (KF) at the inner side of at least one contact finger (101, 201) is circular cylindrical or frustoconical with a smallest radius (RF), which is smaller than the radius (RS) of the corresponding plug pin (S).
8. Plugging device according to at least one of the preceding claims,
   characterized in that the inner side of the contact fingers (101, 201) is coated at least on the contact areas (KF), preferably with nickel and/or silver.
9. Plugging device according to at least one of the preceding claims,
   characterized in that the cavity (HR) tapers towards the distal end, wherein the contact fingers (101, 201) and a carrier body (107, 207) of the contact sleeve carrying the contact fingers are made of a raw material without bends.

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