Elastic Terminal Ferrule, Terminal Assembly, and Charging Seat

An elastic terminal ferrule includes an annular body, a limit structure formed on the annular body, and a mating limit structure formed on the annular body for mating with the limit structure. When the annular body is in a natural state without radial expansion, the limit structure and the mating limit structure are spaced apart from each other in a circumferential direction. When the outer diameter of the annular body is expanded to a predetermined value, the limit structure and the mating limit structure abut against each other in the circumferential direction to prevent further radial expansion of the elastic terminal ferrule.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of the filing date under 35 U.S.C. § 119(a)-(d) of Chinese Patent Application No. 202221257944.3, filed on May 24, 2022.

FIELD OF THE INVENTION

The present invention relates to an elastic terminal ferrule, a terminal assembly comprising the elastic terminal ferrule, and a charging seat comprising the terminal assembly.

BACKGROUND

In the prior art, a charging seat typically includes a housing and a charging terminal installed in the housing. The charging terminal has a cylindrical part suitable for mating with a mating terminal on a charging gun. In order to improve the electrical contact reliability, multiple axial extension slots are usually formed on the cylindrical part of the charging terminal to divide the cylindrical part into multiple elastic arms distributed in the circumferential direction. Multiple elastic arms can make electrical contact with the mating terminal inserted into the cylindrical part.

When the insertion posture of the mating terminal is incorrect, however, such as tilting, it can cause excessive deformation and yielding of the cylindrical part of the charging terminal in the radial direction. If yielding occurs, it will cause the charging terminal to fail and prevent reliable electrical contact with the mating terminal.

SUMMARY

An elastic terminal ferrule includes an annular body, a limit structure formed on the annular body, and a mating limit structure formed on the annular body for mating with the limit structure. When the annular body is in a natural state without radial expansion, the limit structure and the mating limit structure are spaced apart from each other in a circumferential direction. When the outer diameter of the annular body is expanded to a predetermined value, the limit structure and the mating limit structure abut against each other in the circumferential direction to prevent further radial expansion of the elastic terminal ferrule.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

As shown inFIGS.1and2, in the illustrated embodiment, the terminal assembly includes a terminal10and an elastic terminal ferrule20. Terminal10is located at one end of a cylindrical part11suitable for mating with a mating terminal. A plurality of axial extension slots11aare formed on the cylindrical part11. The elastic terminal ferrule20is installed on the outside of the cylindrical part11of the terminal10to prevent excessive expansion of the cylindrical part11in the radial direction. This can prevent yielding deformation of the cylindrical part11of terminal10and increase the service life of the terminal10.

As shown inFIGS.2and3, in the illustrated embodiment, the elastic terminal ferrule20includes an annular body2. The annular body2has two ends211and221. The two ends211and221are free in the circumferential direction of the annular body2. The elastic terminal ferrule20also includes a limit structure1a,2aand a mating limit structure1b,2b. The limit structure1aand2ais formed on the annular body2and near the end211,221of the annular body2. The mating limit structure1band2bis formed on the annular body2for coordination with the limit structure1aand2a.

As shown inFIG.3, when the annular body2is in a free state that has not been radially expanded, the limit structure1a,2aand the mating limit structure1b,2bare spaced in the circumferential direction. That is, there is a certain spacing in the circumferential direction between the limit structure21a,22a, and the mating limit structure1b,2b, allowing the limit structure1a,2aand the mating limit structure1b,2bto move relative to each other within a certain range.

When the outer diameter of the annular body2is expanded to a predetermined value, shown inFIG.5, the limit structure1a,2aand the mating limit structure1band2bare against each other in the circumferential direction to prevent further radial expansion of the elastic terminal ferrule20.

As shown inFIGS.2and3, the elastic terminal ferrule20includes a first ring21and a second ring22. The first ring21has a first root212and a first end211that can move in the circumferential direction relative to the first root212. The second ring22is axially adjacent to the first ring21and connected to the first root212of the first ring21. A notch21aand22ais formed on one of the two adjacent edges of the first ring21and the second ring22, and a protrusion21band22bis formed on the other of the two adjacent edges of the first ring21and the second ring22and axially protrudes into the notch21aand22a.

As shown inFIG.5, when the mating terminal is inserted into the cylindrical part11of terminal10in an incorrect posture, for example, when inserted obliquely, the outer diameter of the elastic terminal ferrule20will be expanded to the predetermined value. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the protrusion21band22bis circumferential against the inner side of the notch21aand22ato prevent further radial expansion of the elastic terminal ferrule20and the cylindrical part11of the terminal10. In this way, it is possible to prevent the cylindrical part11of the terminal10from being excessively expanded radially.

As shown inFIG.3, a blocking surface1aand2ais formed on the inner side of notch21aand22a, which extends axially and radially. A mating blocking surface1band2bis formed on the protrusion21band22b, which extends axially and radially and is circumferential opposite to the blocking surface1aand2a. In the illustrated embodiment, the blocking surface1aand2ais served as the aforementioned limit structure, and the mating blocking surfaces1band2bis served as the aforementioned mating limit structure.

When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the blocking surface1aand2ais circumferential against the mating blocking surface1band2bto prevent further radial expansion of the elastic terminal ferrule20and the cylindrical part11of the terminal10.

As shown inFIGS.2and3, the second ring22has a second root222and a second end221that can move in the circumferential direction relative to the second root222. The second root222of the second ring22is connected to the first root212of the first ring21. The aforementioned notch21aand22aincludes a first notch21aformed on the periphery of the first ring21near the first end211. The aforementioned protrusion21band22bincludes a first protrusion22bformed on the periphery of the second ring22near the second root222. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the first protrusion22bis circumferential against the inner side of the first notch21ato prevent further radial expansion of the elastic terminal ferrule20.

As shown inFIG.3, a first blocking surface1ais formed on the inner side of the first notch21a, which extends axially and radially. A first mating blocking surface2bis formed on the first protrusion22b, which extend axially and radially and is circumferential opposite to the first blocking surface1a. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the first blocking surface1ais circumferential against the first mating blocking surface2bto prevent further radial expansion of the elastic terminal ferrule20.

As shown inFIG.3, the aforementioned notch21aand22aalso includes a second notch22aformed on the periphery of the second ring22near the second end221. The aforementioned protrusion21band22balso includes a second protrusion21bformed on the periphery of the first ring21near the first root212. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the second protrusion21bis circumferential against the inner side of the second notch22ato prevent further radial expansion of the elastic terminal ferrule20.

As shown inFIG.3, a second blocking surface2ais formed on the inner side of the second notch22a, and the second blocking surface2aextends axially and radially. A second mating blocking surface1bis formed on the second protrusion21b, and the second mating blocking surface1bextends axially and radially and is circumferential opposite to the second blocking surface2a. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the second blocking surface2ais circumferential against the second mating blocking surface1bto prevent further radial expansion of the elastic terminal ferrule20.

The elastic terminal ferrule20, as shown inFIG.3, also includes a connection portion23, which connects the first root212of the first ring21and the second root222of the second ring22.

The aforementioned elastic terminal ferrule20can be an integral stamping component formed by stamping a single sheet. This can reduce manufacturing costs.

As shown inFIG.2, a positioning slot 1 lb is formed on the outer surface of the end of the cylindrical part11of the terminal10, and the elastic terminal ferrule20is positioned in the positioning slot 1 lb to prevent axial movement of the elastic terminal ferrule20.

When the outer diameter of the cylindrical part11of terminal10is expanded to a maximum allowable value, the protrusions21band22bon the elastic terminal ferrule20are circumferential against the inner side of the notches21aand22aof the elastic terminal ferrule20to prevent further radial expansion of the elastic terminal ferrule20and the cylindrical part11of terminal10. In this way, it is possible to prevent the outer diameter of the cylindrical part11of terminal10from expanding beyond its maximum allowable value, thereby ensuring that the cylindrical part11of terminal10will not undergo yield deformation.

As shown inFIG.4, in the illustrated embodiment, when the mating terminal is inserted into the cylindrical part11of terminal10in the correct posture, the outer diameter of the cylindrical part11is expanded to a first value less than the maximum allowable value, and the outer diameter of the elastic terminal ferrule20is expanded to a second value less than the predetermined value. At this point, the aforementioned blocking surfaces1a,2a, and the aforementioned mating blocking surfaces1b,2bhave not yet reached the position of contact with each other in the circumferential direction, that is, there is still a certain gap in the circumferential direction between the blocking surfaces1a,2a, and the mating blocking surfaces1b,2b.

When the elastic terminal ferrule20is in a natural state without radial expansion, as shown inFIG.1, the outer diameter of the elastic terminal ferrule20is equal to an initial value. When the elastic terminal ferrule20is installed on the cylindrical part11and the mating terminal is not inserted into the cylindrical part11, the outer diameter of the elastic terminal ferrule20is expanded to slightly greater than the initial value, in order to apply a predetermined radial tightening force on the cylindrical part11.

A guiding slope11c, shown inFIG.2, is formed on the end of the cylindrical part11of terminal1, which is used to guide the elastic terminal ferrule20to fit onto the cylindrical part11of terminal1. A plurality of axial extension slots11aon the cylindrical part11are evenly spaced in the circumferential direction and extend axially to the end face of the cylindrical part11, thereby separating the cylindrical part11of terminal1into multiple elastic cantilevers110.

As shown inFIG.1, the terminal10also includes a flat end part12located at its other end. A conductor core of a cable can be welded to the flat end part12of terminal10. However, the present invention is not limited to this, and the flat end part12of terminal10can also be riveted or otherwise attached to the conductor core of the cable.

FIG.6shows an illustrative assembly view of a terminal assembly according to another exemplary embodiment of the present invention.FIG.7shows an illustrative perspective view of the elastic terminal ferrule20of the terminal assembly shown inFIG.6. The difference between the terminal assembly shown inFIGS.6and7and those shown inFIGS.1to5is only in the structure of the elastic terminal ferrule20to prevent excessive radial expansion.

As shown inFIG.7, a first radial protrusion24aand a second radial protrusion24bare formed on two sides of the notch21a,22a, and the protrusions21band22bfacing each other in the circumferential direction, respectively. The first radial protrusion24aand the second radial protrusion24bcan be formed by stamping. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the first radial protrusion24acircumferentially abuts against the second radial protrusion24bto prevent further radial expansion of the elastic terminal ferrule20.

Due to the predetermined height of the first radial protrusion24aand the second radial protrusion24bradially protruding from the outer surface of the elastic terminal ferrule20, when subjected to excessive radial expansion tension, the first radial protrusion24aof the elastic terminal ferrule10will also reliably rest against the second radial protrusion24b, without crossing the second radial protrusion24bin the circumferential direction.

As shown inFIG.7, a blocking surface24a′ is formed on the first radial protrusion24a, and the blocking surface24a′ extends axially and radially. A mating blocking surface24b′ is formed on the second radial protrusion24b, which extends axially and radially and is opposite to the blocking surface24a′ in the circumferential direction. When the outer diameter of the elastic terminal ferrule20is expanded to the predetermined value, the blocking surface24a′ will be circumferential against the mating blocking surface24b′ to prevent further radial expansion of the elastic terminal ferrule20.

Except for the aforementioned differences, the other features of the elastic terminal ferrule20shown inFIGS.6and7are basically the same as those shown inFIGS.1to5. For the sake of simplicity, it will not be repeated here, and reference can be made to the elastic terminal ferrule20shown inFIGS.1to5.

In an exemplary embodiment of the present invention, a charging seat is also disclosed. The charging seat includes a housing and the aforementioned terminal assembly, which is installed in the housing. The terminal in the terminal assembly can be a charging terminal.

In the illustrated embodiments, the annular body2of the elastic terminal ferrule20has two rings21and22. However, the present invention is not limited to the illustrated embodiments, for example, the annular body2of the elastic terminal ferrule20may also have a single ring.