Electrical device with soldered joint

Abstract

An electrical device with a soldered joint is disclosed. In an embodiment, an electrical device includes at least one soldered joint having a first wire soldered at one end to the device, wherein the first wire bears with a bearing surface on the device, and wherein the first wire has at least one bend in a region of the bearing surface of the first wire on the device.

Claims

1. An electrical device comprising: at least one soldered joint comprising a first wire soldered at one end to the device, wherein the first wire bears with a bearing surface on the device, wherein the first wire has at least one bend in a region of the bearing surface of the first wire on the device, and wherein the bearing surface of the first wire has a rounded end in plan view.

2. The device according to claim 1, wherein the first wire has a further bend in a region of a flattened portion which is directed towards a contact surface.

3. The device according to claim 1, wherein the first wire has a flattened portion in the region of the bearing surface.

4. The device according to claim 1, wherein the device has at least one contact surface for the soldered joint which is coated with an electrically conductive metal.

5. The device according to claim 4, wherein the bearing surface of the first wire is shorter than the contact surface.

6. The device according to claim 1, wherein the first wire extends after the bend with a gap relative to a contact surface when viewed from the bearing surface.

7. The device according to claim 6, wherein the soldered joint comprises a solder, a greater part of which is arranged in a region in which the first wire extends with the gap relative to the contact surface.

8. The device according to claim 1, wherein the bend is arranged in the first wire at an end of a flattened portion where it develops into a region of a round cross-sectional shape.

9. The device according to claim 8, further comprising a first wire insulation of a synthetic polymer material, which begins only in the region of round cross-sectional shape.

10. The device according to claim 1, wherein the device comprises an NTC ceramic.

11. The device according to claim 1, further comprising a polymer covering, which envelops the device, the soldered joint and the first wire to as far as behind a last bend.

12. The device according to claim 1, further comprising a second contact surface, to which a second wire identical in form to the first wire is soldered.

13. An electrical device comprising: at least one soldered joint comprising a wire soldered at one end to the device, wherein the wire bears with a bearing surface on the device, wherein the wire has at least one bend in a region of the bearing surface of the wire on the device, wherein the wire has a flattened portion in the region of the bearing surface, and wherein the bend is arranged in the wire at an end of the flattened portion where it develops into a region of a round cross-sectional shape.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Preferred exemplary embodiments of the present invention are described below with reference to the figures.

(2) FIG. 1 shows a perspective view of an NTC ceramic with two wires at opposing contact points; and

(3) FIG. 2 shows a device together with wire in sectional view and plan view.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

(4) FIG. 1 is a perspective representation of a preferred embodiment of an electrical device B. Two opposing contact surfaces E on a main body of an NTC ceramic C are coated with silver. A wire with its flattened portion F or with its flattened bearing surface rests against each of these contact surfaces E. A first bend K1 is present in the wires in the region of the flattened portion F. The length of the flattened wire portions, which constitute the bearing surface, bearing on the contact surfaces, i.e., the length of the respective wire end D up to the first bend, is selected to be smaller than the contact surface of the device. In this respect, the wire end D lies close to one edge of the contact surface E, such that the wire has a further portion M to O which extends above the contact surface E. After this first bend K1 the wires, which are still flattened in this portion, extend at an angle of about 60 to the contact surface E away from the ceramic body C. At the end of the flattened portion F the wires develop into a region R with a round cross-sectional shape. In addition, the wires have a second bend K2 at the end of their flattened portion F. The second bend is angled in the opposite direction to the first, such that the wires continue at a smaller, more acute angle of about 10 to the contact surface. The gap A between this region of round cross-section R and the contact surface E may fill up with solder during the soldering process and leads to increased stability of the soldered joint. As the wires continue, they are provided with insulation J consisting of a polymer material.

(5) FIG. 2 shows a schematic cross-section of the electrical device B with a wire, and a plan view onto the wire. The contact surface E shown of an NTC ceramic C is coated with silver. A wire rests with its flattened portion F on this contact surface E. On its flattened side, the wire has a rounded end E. In the region of the flattened portion F a first bend K1 is present in the wire, forming the angle . The length of the flattened wire portions L bearing on the contact surfaces, i.e., from the end of the wire up to its first bend K1, is selected to be smaller than the contact surface E of the device. After this first bend K1 the flattened wire extends at an angle of about 60 to the contact surface E away from the ceramic body C. After the wire has moved away from the ceramic over the course of portion M, it has a further bend K2. In the following portions N-P the wire extends at the angle to the contact surface E, wherein <. At the end of the portion N the wire develops into the region O of round cross-sectional shape R. The volume in the region of the gap A between the portions N and O and the contact surface E may fill up with solder during the soldering process and leads to increased stability of the soldered joint. Over the course of the portion P, the wire is provided with a polymer insulation J.

(6) The invention relating to the electrical device with soldered joint is not limited to the exemplary embodiments explained or the figures shown.