Patent Application
20060068646
This application claims priority from German Patent Application No. 10 2004 046 808.7-34, which was filed on Sep. 27, 2004, and is incorporated herein by reference in its entirety.
The invention relates to connection parts and to the production of connection parts in the field of electrical or electronic devices and assemblies using plastics.
Here, it is often necessary to provide connection elements which can be subjected to high loads and are suitable for external electrical connection. Such elements designed for high currents are also referred to in the context of the present invention as load connections. Said load connections generally have a connection lug having a hole. A connecting screw can engage through the hole and be screwed to a corresponding screw element arranged beneath the lug, for example a screw nut. An external connection, for example by means of a screw-connected contact element, can thus be realized.
In order to compensate for tolerances between the connection element and the external contact element to be mounted, the corresponding connecting element (screw nut) needs to be capable of moving. It can therefore not be injection molded into the plastic base body, generally provided, of the connection part.
Against this background it is conceivable for the load connection to be inserted into the plastic body by means of a fixing section or fixing region (part of the load connection) such that the connection lug overlaps the screw nut once said screw nut has been placed beneath the lug. The plug or clamping connection thus formed does not, however, ensure reliable fixing of the load connection in all operating situations.
The fixing region of the load connection could also be injection molded into the plastic body and the connection lug bent back onto the screw nut once said screw nut has been inserted. This has the advantage of a reliable fixing of the load connection to the plastic body, but requires an additional bending operation over an undefined bending edge. This may require readjustment of the connection lug. The bending brings about high loads on the plastic at the bending edge and may produce cracks in the connection lug which may lead to breakage owing to the operating conditions (for example temperature change, vibrations).
Against this background, the object of the invention is to provide a connection part which has a securely and permanently fixed load connection but with a movable screw nut along with cost-effective production. In addition, a method for producing such a connection part will be specified.
This object can be achieved by a connection part comprising a plastic body, at least one electrical connection element, a fixing region which is injection molded into the plastic body, a connection lug which has a cutout for a screw connecting element, a corresponding connecting element, a receiving area beneath the connection lug into which the corresponding connecting element can be introduced from outside and which receives said corresponding connecting element, and at least one latching element which holds the corresponding connecting element in the receiving area such that it cannot fall out once it has been inserted.
The corresponding connecting element can be a square nut. Two latching elements can be in the form of latching hooks gripping the corresponding connecting element laterally.
The object can also be achieved by a method for producing a connection part, comprising the steps of injection molding a fixing region of a connection element having a connection lug into a plastic body, introducing a connecting element which corresponds to an external screw connecting element from the outside into a receiving area, delimited by the plastic body, beneath the connection lug, and providing on the plastic body at least one latching element which holds the corresponding connecting element in the receiving area such that it cannot fall out once it has been inserted.
One significant aspect of the invention thus consists in injection molding the fixing region of a ready-bent load connection into the plastic body such that the connection lug partially delimits the receiving area of the screw nut and covers that of the connecting element. As a further important aspect of the invention, this makes it possible for the corresponding connecting element to be introduced into the receiving area from the outside and to be held there by at least one latching element such that it cannot fall out.
A permanent, mechanically robust connection between the load connection and the plastic body is thus realized and subsequent processing (for example bending or aligning processes) of the load connection is not required. Material loads on the load connection and the plastic body and the risk of resultant cracks forming in the load connection are thus prevented.
The corresponding connecting element is preferably a screw nut, in particular a square nut. Further preferably, two latching elements may be provided in the form of latching hooks gripping the corresponding connecting element laterally.
The invention will be explained by way of example in more detail beneath with reference to a drawing, in which:
FIGS. 1 to 4 show method steps in the production of a connection part according to the invention.
In order to illustrate the production,
Two lateral latching hooks 10, 11 spring open laterally during the insertion and spring back behind their outer end face 8a when the square nut 8 has been completely inserted (
The screw connecting elements in this case come into screw-like engagement with the internal thread of the square nuts 8, 9 which are held in the receiving areas 2, 3 by the latching elements (latching hooks) 10, 11 and 14, 15, respectively, such that they cannot fall out but such that they can move to such an extent that they make possible, owing to their ability to move, adaptation to the longitudinal axis of the screw to be matched and, as a result, compensation of tolerances between the connection element and the external contact element to be mounted. The square nut thus forms in each case a corresponding connecting element for said metal screw.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102004046808.7-34 | Sep 2004 | DE | national |
