EP4668497A1

EP4668497A1 - Tube terminal with pin in core

Info

Publication number: EP4668497A1
Application number: EP24183722.8A
Authority: EP
Inventors: Pawel Kozak; Emilia MUSIAL; Jaroslaw Koziol; Michal KACZMARCZYK
Original assignee: Aptiv Technologies AG
Current assignee: Aptiv Technologies AG
Priority date: 2024-06-21
Filing date: 2024-06-21
Publication date: 2025-12-24

Abstract

An electrical contact terminal comprises a connecting means, configured and dedicated to being connected to an electrical component; a crimping means, configured and dedicated to being crimped around an electrical conductor, the crimping means comprises a hollow cylinder and at least one pin, wherein the pin is arranged in the hollow cylinder and the pin extends axially over at least half of the length of the hollow cylinder.

Description

1. Field of the invention

This invention relates to an electrical contact terminal, to establish a crimped connection between the terminal and an electrical conductor, and a terminal assembly comprising a terminal and a cable.

2. Background

In many applications, as e.g., the automotive industry, electrical contact terminals are important in ensuring efficient current flow and mechanical stability for instance in electrical power transfer. Traditional electrical terminals often face challenges related to mechanical and electrical reliability, and a subpar electrical conductivity in the contact area between an electrical conductor and the terminal.
CN 219874095 U discloses a wiring terminal which comprises a coating part used for being connected with a cable, the coating part is provided with a cavity for the cable to extend into, one end of the coating part is open, the other end of the coating part is provided with a connector used for being connected with an electric appliance part, and a tensioning piece is arranged in the coating part corresponding to one end.
It is disadvantageously here, that the tensioning piece comprises a sharp tip and the tensioning piece is considerably shorter than the axial dimension of the cavity. This results in a decreased electrical contact area and less mechanical stability when the tensioning piece is subjected into a conductor. Thus, there is a demand for a mechanically and electrically enhanced terminal.
In view of the foregoing, there is a need for an improved terminal. It is thus an object of the present invention to overcome some or all the deficiencies of the prior art.

3. Summary

The above objects are at least partially achieved by the subject matter of independent claim 1. Preferred embodiments are the subject of the dependent claims, and the skilled person will find clues to other suitable aspects of the present invention in the overall disclosure of the present application.
An aspect of the invention relates to an electrical contact terminal, the terminal comprising a connecting means, configured and dedicated to being connected to an electrical component; a crimping means, configured and dedicated to being crimped around an electrical conductor. The crimping means comprises a hollow cylinder and at least one pin, wherein the pin is arranged in the hollow cylinder and the pin extends axially over at least half of the length of the hollow cylinder.
Such an electrical contact terminal can be used in wiring systems to ensure a secure and reliable connection between e.g., the wiring harness and electrical components, such as sensors or control modules or other components that require power transfer with a low contact resistance. The connecting means allows for a quick and stable attachment to the component, while the crimping means, with its hollow cylinder and axially extending pin, provides an improved mechanical and electrical connection to the conductor. This design enhances the terminal's durability and ensures consistent electrical performance, reducing the likelihood of connection failures due to e.g., vibrations or thermal cycling. In particular, this type of connection allows for a reduced electrical contact resistance, as not just the hollow cylinder is subjected to the electrical conductor, but also the pin, thus increasing the area of the connecting means that is in contact with an electrical conductor.
Further improvement can be achieved when at least one pin is arranged coaxially in the hollow cylinder.
Such a coaxially arranged pin within the hollow cylinder ensures a uniform distribution of mechanical stress and electrical contact, e.g., along the length of the terminal. Furthermore, this configuration could be particularly advantageous in environments, where maintaining a reliable connection is important. Such a pin might function as a guiding structure and therefore the coaxial arrangement of the pin helps in minimizing potential misalignment during the crimping process, thus leading to a more stable and efficient connection between the electrical conductor and the terminal.
Further improvement is yielded when the connecting means comprises a lug.
Such a lug can be designed for easy attachment to a variety of electrical components, like battery terminals or electrical grounding points. The inclusion of a lug provides a simple and secure method for fastening the terminal which ensures a stable and durable connection. This design can be beneficial in applications requiring frequent maintenance or replacement of components, as it allows for quick disconnection and reconnection without specialized tools.
This embodiment can be further improved when the connecting means comprises at least one through hole.
Such a through hole allows for secure attachment using bolts, screws, or other fasteners, providing a reliable connection point for various electrical components. For instance, the through hole can facilitate a robust connection to e.g., battery terminals or electrical grounding points, ensuring decreased electrical resistance and thereby increased conductivity.
Further improvement is achieved when the pin has a tip which forms a half sphere.
Such a hemispherical tip can enhance the terminal's ability to create a strong electrical contact with the conductor. When the crimping means is engaged, the half-spherical tip of the pin can pierce the conductor more effectively, ensuring a secure and consistent electrical connection. This design is advantageous in applications where reliable electrical performance is important. The half-spherical tip also helps distribute the mechanical stress more evenly, reducing the risk of damage to the conductor and improving the overall durability and lifespan of the terminal.
Even further improvement is achieved when the pin has a tip which is not pointed.
Such a not pointed tip minimizes the risk of damage to the conductor during the crimping process, as it avoids puncturing or excessively deforming the conductor's strands. The non-pointed tip ensures a more gentle but firm contact, which is beneficial for maintaining the integrity of the conductor over time. This can be useful in applications where the conductor may be subject to flexing, bending or other movement. The non-pointed tip also helps in achieving a more uniform electrical contact, reducing the likelihood of current hotspots, thus improving electrical performance.
Further improvement is achieved when the pin has a radius, and the radius is a fraction of the outer radius of the hollow cylinder, wherein the fraction is in the range of 0,05 to 0,4, more preferably in the range of 0,1 to 0,3, most preferably in the range of 0,15 to 0,25.
For instance, if the outer radius of the hollow cylinder is 4 mm, the pin's radius would be between 0,2 mm and 1,6 mm, based on the exemplary range of 0,05 to 0,4. This proportional design can ensure improved mechanical stability and electrical conductivity. Such a range for the pin's radius fraction is chosen for instance to balance strength and flexibility, allowing the hollow cylinder to be effectively crimped around the conductor and around the pin without excessive deformation or insufficient contact. By improving the pin's radius in this way, the terminal can achieve improved performance in terms of durability, electrical conductivity, and ease of installation.
Even further improvement is achieved when the hollow cylinder has a constant inner diameter in the region of the axial extension of the pin.
Such an uniform inner diameter can ensure that an electrical conductor can be securely and evenly positioned within the cylinder, providing consistent mechanical support and electrical contact. The constant inner diameter can simplify the manufacturing process and enhance the durability of the terminal by reducing the risk of mechanical stress concentrations that might lead to failure.
Further improvement is achieved when the crimping means comprises teeth, configured and dedicated to improving the electrical connection between the cylinder and/or the pin and a cable in a crimped condition.
Such type of teeth can be positioned to "bite" into the conductor when crimped, improving the mechanical grip and electrical contact. This design ensures a more secure and stable connection, reducing the risk of the cable slipping out or losing contact over time. The teeth can also help to penetrate any oxidation layer on the conductor, enabling a cleaner and conductively improved interface. This can result in lower contact resistance with an enhanced capacity to carry current, and improved overall performance of the electrical system. The teeth configuration can also help maintaining the integrity of the connection under conditions of vibration or thermal cycling, thus extending the lifespan and reliability of the terminal.
This embodiment can be further improved when the teeth are arranged on the pin and/or the inner side of the hollow cylinder.
Such an arrangement of teeth can enhance the mechanical and electrical connection between the terminal and the conductor by providing multiple points of contact. When the crimping means is engaged, the teeth can grip the conductor firmly from the inside of the hollow cylinder and the outside of the pin, thus enabling a secure and stable connection. The teeth on the pin and/or inner cylinder can help to penetrate the conductor's surface, e.g., breaking through any oxidation layer and ensuring a clean and conductive interface. This can result in lower electrical resistance and better current flow. Additionally, the multiple points of contact provided by the teeth help distribute mechanical stress more evenly.
Further improvement is achieved when the pin extends over a fraction of the length of the hollow cylinder, wherein the fraction is in the range of 0,5 to 1, preferably in the range 0,75 to 1, most preferably in the range 0,8 to 1.
Such a terminal features a pin that extends over an important portion of the hollow cylinder's length, for instance between 50% and 100%. For example, if the hollow cylinder is 10 mm long, the pin would extend between 5 mm and 10 mm. This extensive axial extension can ensure a large contact area between the pin and the conductor, improving the mechanical stability and electrical performance of the connection. This configuration could be beneficial in high-current applications where a larger contact area can reduce resistance and as well improves heat dissipation. By extending the pin over most of the cylinder's length, the terminal can ensure a more secure crimp, reducing the risk of accidental disconnection.
Another way of improvement is achieved when the pin instead extends over more than the length of the hollow cylinder.
Such a terminal provides an additional length of the pin for contact with the electrical conductor, enhancing the mechanical stability and electrical connectivity of the terminal. The extended pin can facilitate alignment and insertion of the conductor during the assembly process, ensuring a more consistent and reliable connection. By extending the pin beyond the cylinder, the terminal can improve the durability and performance of the electrical connection, thus reducing the likelihood of connection failures and ensuring long-term reliability in demanding conditions.
A preferred embodiment is a terminal assembly, comprising an electrical contact terminal in accordance with the invention and a cable, comprising an electrical conductor in form of multiple wire strands.
The multiple wire strands of the conductor of such a terminal assembly can provide flexibility and durability, making the assembly suitable for use in dynamic environments where the cable may be subject to bending, flexing or other movement. The terminal assembly can effectively minimize electrical resistance and enhance the mechanical grip on the wire strands of the conductor, reducing the risk of disconnection or signal loss due to vibration, thermal cycling, and/or mechanical stress.
This embodiment can be further improved when the wire strands are arranged inside the hollow cylinder, and wherein the hollow cylinder is crimped around the wire strands.
Crimping the hollow cylinder around the wire strands can ensure that the strands are tightly held together around the pin inside the hollow cylinder, preventing them from fanning out while decreasing the electrical resistance at the contact point. This can result in improved conductivity and a more stable electrical and mechanical connection. Additionally, the crimped connection can provide improved resistance to mechanical stresses, such as vibration and thermal cycling.

4. Brief description of the figures

In the following, preferred embodiments of the disclosure are disclosed by reference to the accompanying figures.

Fig. 1:: illustrates a terminal assembly according to the invention in a perspective view.
Fig. 2:: shows the terminal assembly of Fig. 1 after assembly in a perspective view.
Fig. 3:: shows the terminal in a transparent perspective view.
Fig. 4:: illustrates the terminal assembly in a cross-sectional view.

5. Detailed description of the figures

The subsequent sections provide a detailed description of the invention, referencing the accompanying illustrations for clarity. The descriptions represent examples only and are not intended to limit the invention's scope. Identical reference numerals across the figures and text denote the same components. The illustrations may not reflect actual size or scale; their dimensions, proportions, and depictions of elements might be enhanced for better understanding and visual convenience.
Figure 1 illustrates a terminal assembly according to the invention in a perspective view. The electrical contact terminal 100 is aligned with the cable 200. The cable 200 comprises an electrical conductor 202 and the electrical conductor 202 comprises multiple wire strands 204. The cable 200 is coaxially aligned with the terminal 100. The terminal 100 comprises a connecting means 110 and a crimping means 120. The connecting means 110 comprises a lug 112. The crimping means 120 comprise a hollow cylinder 122 and coaxially arranged inside the hollow cylinder 122 is a coaxially arranged pin 124 with a tip 126.
Such a coaxial alignment can ensure that the strands are evenly distributed within the cylinder. The crimping means 120 can fasten the wire strands 204 inside the hollow cylinder 122 around the pin 124, ensuring a stable and low-resistance electrical connection. The connecting means 110 with its lug 112 allows for easy attachment to various electrical components. The coaxially arranged pin 124 within the hollow cylinder 122 can enhance the mechanical stability and electrical contact of the assembly. The pin's tip 126 ensures effective engagement with the wire strands, providing a reliable and durable connection.
Figure 2 shows the terminal assembly according to the invention after assembly in a perspective view: The cable 200 is connected with the electrical contact terminal 100 and is aligned inside the hollow cylinder 122 of the crimping means 120. The lug 112 of the connecting means 110 comprises a through hole 114.
The cable 200 with its multiple wire strands 204 can be securely crimped within the hollow cylinder 122. This can ensure a robust mechanical and electrical connection between the cable 200 and the terminal 100. The through hole 114 in the lug 112 of the connecting means 110 can facilitate attachment to external electrical components using bolts or screws, providing a reliable fastening point. The crimping means 120 can ensure that the wire strands 204 are tightly secured inside the hollow cylinder 122 around a pin, reducing electrical resistance and enhancing the durability of the connection. The through hole 114 in the lug 112 allows for versatile integration into various electrical systems.
Figure 3 shows the terminal in a transparent perspective view. One can see the electrical contact terminal 100 with the connecting means 110 and the crimping means 120. The connecting means 110 comprises the lug 112 and the through hole 114 in the lug. In the transparent view one can clearly see the crimping means 120 comprising the hollow cylinder 122 and the coaxially aligned pin 124 inside it. The pin 124 has a half-spherical tip 126 and extends over nearly 80% of the length of the hollow cylinder 122.
The not-pointed half-spherical tip 126 of the pin 124 can provide improved electrical contact with the conductor strands when crimped. Extending the pin 124 over nearly 80% of the length of the hollow cylinder 122 ensures a large contact area, enhancing both mechanical stability and electrical conductivity. The pin thus extends over a fraction of the length of the hollow cylinder, wherein the fraction is in the range of 0,5 to 1, preferably in the range 0,75 to 1, most preferably in the range 0,8 to 1. The lug 112 with its through hole 114 allows for easy attachment to other electrical components. The extended pin 124 with the half-spherical tip 126 can improve electrical contact quality and reduce resistance, while the through hole 114 in the lug facilitates mounting and integration into electrical systems.
Figure 4 illustrates the terminal assembly according to the invention in a cross-sectional view. The crimping means 120 having the hollow cylinder 122 and the coaxially aligned pin 124 inside it, is clearly visible. One can take from the cross-sectional view, how the pin 124 has a half-spherical tip 126 and extends over nearly 80% of the length of the hollow cylinder 122. The cable 200 is coaxially aligned with the hollow cylinder 122 and the pin 124 with the tip 126 penetrates the electrical conductor 202 with the wire strands 204.
The coaxially arranged half-spherical tip 126 of the pin 124 can ensure a secure and effective connection by penetrating the conductor's wire strands 204, thus enhancing mechanical and electrical stability. The coaxial alignment of the cable 200 with the hollow cylinder 122 ensures that the conductor 202 is properly positioned inside the hollow cylinder 122 for optimal crimping. Such an alignment and the penetration of the pin 124 into the wire strands 204 can create a strong and reliable electrical connection, reducing resistance and improving conductivity. The through hole 114 in the lug 112 can facilitate secure attachment to other components.

Reference list:

100:: electrical contact terminal

110:: connecting means
112:: lug
114:: through hole

120:: crimping means
122:: hollow cylinder
124:: pin
126:: tip

200:: cable
202:: electrical conductor
204:: wire strands

Claims

An electrical contact terminal (100), the terminal comprising:
A connecting means (110), configured and dedicated to being connected to an electrical component;

A crimping means (120), configured and dedicated to being crimped around an electrical conductor (202), the crimping means (120) comprising:
A hollow cylinder (122) and at least one pin (124), wherein the pin (124) is arranged in the hollow cylinder (122) and the pin (124) extends axially over at least half of the length of the hollow cylinder (122).
A terminal according to claim 1, wherein at least one pin (124) is arranged coaxially in the hollow cylinder (122).
A terminal according to claim 1 or 2, wherein the connecting means (110) comprises a lug (112).
A terminal according to any of the preceding claims, wherein the connecting means (110) comprises at least one through hole (114).
A terminal according to any of the preceding claims, wherein the pin (124) has a tip (126) which forms a half sphere.
A terminal according to any of the preceding claims, wherein the pin (124) has a tip (126) which is not pointed.
A terminal according to any of the preceding claims, wherein the pin (124) has a radius, and the radius is a fraction of the outer radius of the hollow cylinder (122), wherein the fraction is in the range of 0,05 to 0,4, more preferably in the range of 0,1 to 0,3, most preferably in the range of 0,15 to 0,25.
A terminal according to any of the preceding claims, wherein the hollow cylinder (122) has a constant inner diameter in the region of the axial extension of the pin (124).
A terminal according to any of the preceding claims, wherein the crimping means (120) comprises teeth, configured and dedicated to improving the electrical connection between the cylinder and/or the pin (124) and a cable (200) in a crimped condition.
A terminal according to claim 9, wherein the teeth are arranged on the pin (124) and/or the inner side of the hollow cylinder (122).
A terminal according to any of the preceding claims, wherein the pin (124) extends over a fraction of the length of the hollow cylinder (122), wherein the fraction is in the range of 0,5 to 1, preferably in the range 0,75 to 1, most preferably in the range 0,8 to 1.
A terminal according to claims 1 to 10, wherein the pin (124) extends over more than the length of the hollow cylinder (122).
A terminal assembly, comprising an electrical contact terminal (100) in accordance with any of the preceding claims and a cable (200), comprising an electrical conductor (202) in form of multiple wire strands (204).
The terminal assembly of claim 13, wherein the wire strands (204) are arranged inside the hollow cylinder (122), and wherein the hollow cylinder (122) is crimped around the wire strands (204).