US-12627191-B2 - Joined assembly and production method thereof

US12627191B2US 12627191 B2US12627191 B2US 12627191B2US-12627191-B2

Abstract

A joined assembly comprises a wire bundle and a metallic member joined to the wire bundle. The wire bundle includes a bundle of a plurality of conductive wires which are isolated from each other using inter-wire insulating layers and adhered to each other, the inter-wire insulating layers being made from insulating resin. The wire bundle includes a head portion and a head extension. The head portion is arranged on a first side of the wire bundle in a lengthwise direction (Da) thereof. The head extension extends from the head portion to a second side of the wire bundle away from the first side in the lengthwise direction. The metallic member includes a metallic member connecting portion arranged in contact with the head extension. The conductive wires are kept adhered to each other through the inter-wire insulating layers in the head extension and fusion-joined in the head portion to a portion of the metallic member connecting portion. The head portion of the wire bundle has the inter-wire insulating layers removed therefrom.

Inventors

Kazuki KODA
Hideaki Shirai
Tsuguya SHIMOSAKAMOTO

Assignees

DENSO CORPORATION

Dates

Publication Date: 20260512
Application Date: 20240105
Priority Date: 20210709

Claims (6)

1 . A production method for a joined assembly including a wire bundle and a metallic member, comprising: using a bundle of a plurality of conductive wires as the wire bundle, the conductive wires being isolated from each other through inter-wire insulating layers made from insulating resin; holding a head portion of the wire bundle in contact with a metallic member connecting portion of the metallic member, the head portion being arranged on a first side of the wire bundle in a lengthwise direction of the wire bundle, the head extension extending from the head portion to a second side of the wire bundle away from the first side in the lengthwise direction, the conductive wires being kept adhered to each other through the inter-wire insulating layer within the head extension, and making an end-to-end joint which is created by fusion-joining the conductive wires within the head portion of the wire bundle to a portion of the metallic member connecting portion after the head extension is retained to the metallic member connecting portion, wherein the end-to-end joint is created by emitting an energy beam to fuse and weld the head portion of the wire bundle to the portion of the metallic member connecting portion and also to remove the inter-wire insulating layers from the head portion.
2 . The production method as set forth in claim 1 , wherein the metallic member is made from one of copper and copper alloy, the conductive wires are made from one of copper and copper alloy, the end-to-end joint is produced by using a laser beam whose wavelength is 400 nm to 600 nm in a form of the energy beam.
3 . The production method as set forth in claim 1 , wherein the inter-wire insulating layers have an average thickness of 3 to 30 μm.
4 . The production method as set forth in claim 1 , wherein emission of the energy beam is performed multiple times.
5 . The production method as set forth in claim 1 , wherein the end-to-end joint is created by steps of emitting the energy beam whose energy density is set to a first level to remove the inter-wire insulating layers from the head portion and then emitting the energy beam whose energy density is changed to a second level which is higher than the first level to fusion-join the head portion of the wire bundle to the portion of the metallic member connecting portion.
6 . The production method as set forth claim 1 , wherein the wire bundle has the conductive wires twisted in a form of a twisted-wire conductor, and holding the head portion of the wire bundle in contact with the metallic member connecting portion of the metallic member is achieved by retaining the head extension in contact with the metallic member connecting portion with the conductive wires being kept twisted within the head extension.

Description

CROSS REFERENCE TO RELATED DOCUMENT The present application is a continuation of Application No. PCT/JP2022/024165, filed Jun. 16, 2022, which claims the benefit of priority of Japanese Patent Application No. 2021-114458 filed on Jul. 9, 2021. The entire disclosures of each of the above applications are incorporated herein by reference. TECHNICAL FIELD This disclosure relates generally to a joined assembly of a bundle of wires and a metallic member and production method thereof. BACKGROUND OF ART Patent literature 1 teaches a joining method to join a wire bundle including conductive wires covered with insulating resin layers to a metallic terminal. Specifically, the joining method includes a first step of pressing the metallic terminal and a joint of the wire bundle to the metallic terminal to firmly adhere the metallic terminal and the joint of the conductive wires to each other and a second step of supplying an electrical current to the metallic terminal with the metallic terminal and the joint of the wire bundle being kept pressed together. This generates thermal energy to plastically deform the conductive wires at the joint and discharge melted insulating resin from the joint. PRIOR ART DOCUMENT Patent Literature PATENT LITERATURE 1: Japanese Patent First Publication No. 2020-27726 SUMMARY OF THE INVENTION A joined assembly which includes a wire bundle (equivalent to the wire bundle taught in Patent literature 1) and a metallic member (equivalent to the metallic terminal taught in Patent literature 1) may be produced in a way other than that discussed above. For instance, there may be proposed a joint assembly in which a joint between the wire bundle and the metallic member contains fused materials of the wire bundle and the metallic member. In a production process of such a type of a joined assembly including a wire bundle of a plurality of conductive wires electrically isolated from each other through inter-wire insulating layers, a portion of the wire bundle which is required to be fusion-joined is, in some cases, first loosened to remove the inter-wire insulating layer partially therefrom. We have studied and found that the loosening of the bundle of the conductive wires will be a factor resulting in reduction in productivity of the joined assembly. This disclosure was made in view of the above problem. It is an object to provide a joined assembly designed to avoid a reduction in productivity in a production process thereof and to provide a production method of such a joined assembly. According to one aspect of this disclosure in order to achieve the above object, there is provided a joined assembly which comprises: (a) a wire bundle; and (b) a metallic member joined to the wire bundle. The wire bundle includes a bundle of a plurality of conductive wires which are isolated from each other using inter-wire insulating layers and adhered to each other. The inter-wire insulating layers are made from insulating resin. The wire bundle includes a head portion and a head extension. The head portion is arranged on a first side of the wire bundle in a lengthwise direction thereof. The head extension extends from the head portion to a second side of the wire bundle away from the first side in the lengthwise direction. The metallic member includes a metallic member connecting portion arranged in contact with the head extension. The conductive wires are kept adhered to each other through the inter-wire insulating layers in the head extension and fusion-joined in the head portion to a portion of the metallic member connecting portion. The head portion of the wire bundle has the inter-wire insulating layers removed therefrom. The above structure facilitates removal of the inter-wire insulating layers using thermal energy generated by fusion-joining the head portion of the wire bundle to the metallic member connecting portion and also enables each of the conductive wires arranged within the head portion to be fusion-joined to the metallic member connecting portion without need for loosening the bundle of the conductive wires in a production process of the joined assembly. This avoids the reduction in productivity of the joined assembly. According to another aspect of this disclosure, there is provided a production method for a joined assembly including a wire bundle and a metallic member, which comprises: (a) using a bundle of a plurality of conductive wires as the wire bundle, the conductive wires being isolated from each other through inter-wire insulating layers made from insulating resin; (b) holding a head portion of the wire bundle in contact with a metallic member connecting portion of the metallic member, the head portion being arranged on a first side of the wire bundle in a lengthwise direction of the wire bundle, the head extension extending from the head portion to a second side of the wire bundle away from the first side in the lengthwise direction, the conductive wires being kept adhered to each other