Interference fit locking mechanism
The twist-lock mechanism with a rotatable locking sleeve and interference fit addresses the issue of space constraints and complexity in existing plug connectors, enabling easy operation and safety release.
Patent Information
- Application Number
- GB2024007916
- Authority / Receiving Office
- GB · GB
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-06-04
- Publication Date
- 2025-12-10
AI Technical Summary
Existing plug connectors require translatory movement for unlocking, which is not feasible in restricted spaces, and existing locking mechanisms are complex and costly.
A twist-lock mechanism with a rotatable locking sleeve and interference fit between inner and outer sleeves, allowing for rotational unlocking and reduced space requirements, along with a breakaway mechanism for safety release.
Enables easy connection and disconnection in confined spaces with reduced complexity and cost, while providing a safety feature for exceeding threshold forces.
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Abstract
Description
Prior art In general, the invention relates to a plug connector comprising two with one another releasably connectable plug elements, one of which is designed to receive the other, namely one component generally designed as a socket to receive the other component designed as a plug insertable or inserted into the socket to achieve a connection between the two correspondingly designed, connectable and releasable plug members. A user-activatable locking mechanism allows the plug to be connected to the socket and vice-versa. Plug connectors or connectors of this kind are well-known in the prior art for connecting two mating ends of cables with one another to achieve an electric current to flow in the connected position. They should easily disconnect the mating ends from one another for maintenance assembly purposes or during regular use. Hence, the plug and the socket are usually connected to cables or to the mating ends of cables, which are located or received within the plug connectors; in other words, the connecting elements of the plug connector are attached to the mating end of the cables to be connected to one another for operation and for an electric current to flow. Disadvantages associated with prior art The locking mechanism or connecting mechanism is typically designed as a push-pull mechanism requiring the pulling of an outer member relative to an inner member to unlock the connection means inside the inner member, e.g., a ball-lock mechanism. This locking mechanism, therefore requires a certain amount of space for moving the outer member relative to the inner member. This space is not always present, especially in restricted areas. Technical problem Starting from the prior art described above and the disadvantages associated therewith, it is, consequently, the technical problem of the present invention to at least partially avoid the disadvantages discussed and provide for an act electric plug connector which can be especially easily released and connected within restricted or confined spaces. Invention This technical problem is already solved by the features of the independent claims. Further features are disclosed in the dependent claims to better put the invention into practice. In the most abstract and most straightforward solution, the invention is solved by providing a locking sleeve on the outside of the outer sleeve that is rotatable around the outer sleeve along a longitudinal axis and by further designing the outer sleeve to change the mating surfaces on the inserting section and the receiving section from clearance or transition fit, allowing the inner sleeve to move relatively to the outer sleeve, to an interference fit, hindering or not allowing relative movement of the inner sleeve with respect to the outer sleeve. Hence, according to the invention, locking and unlocking of the connector is achieved by rotating the locking sleeve around the outer sleeve around its longitudinal axis. The invention can also be called a “twist-lock mechanism” in contrast to the push-pull mechanism known from the prior art. Therefore, the translatory movement in the prior art is replaced with a rotational movement of the locking sleeve around the outer sleeve, reducing the space required. Since the geometry is simpler compared to e.g. ball-bearing push-pull devices, latch based, bayonet or screw-on solutions according to the prior art, generally requiring less parts than these prior art solutions, the invention is also cost-efficient and easy to mass-produce and assemble. The fittings or tolerances used generally depend on the diameter of the plug connector. For a 50 mm diameter of the plug connector the clearance fit may be between +0.025 mm and +0.089 mm and the inference fit between -0.001 mm and -0.042 mm. To further influence the fitting, coatings can be provided on the mating surfaces, namely on the male inserting section and the female receiving section. Especially preferred, and durable coatings having a low coefficient of friction and good hardness are, e.g. Tin, nickel, nickel-phosphorus, silver, hard gold, palladium, palladium-nickel. Preferably hard gold or palladium. The coating can also serve to compensate tolerances, that may occur during manufacturing by turning, forging, etc. Preferably, the plug connector, according to the invention, is made of plastic, preferably produced as injection molding. However, more sturdy embodiments can also be made of metal or partially of metal, combining metal and plastic components as required. One especially interesting aspect of the invention is that a breakaway-mechanism can be integrated into the connector, meaning that when a predefined threshold force is exceeded the typically connected components can disconnect, thereby with providing a safety release feature when certain threshold-forces are exceeded which may vary according to the respective application. On a particularly preferred embodiment, the receiving section defines an outer circumferential periphery with elastically deformable members the members forming two groups of interchanging latches members, a release group, and a locking group. The release group extends less radially outwards with respect to a central axis of rotation than the locking group. Furthermore, a locking sleeve or ring encloses the outer periphery of the receiving section, is relatively rotatable about a longitudinal axis, and comprises a circumferential locking surface on an inner locking side. This circumferential locking surface comprises two sets of interchanging surfaces, a longer set and a shorter set, the longer set of locking surfaces extending further radially towards the longitudinal axis than the shorter locking set of locking surfaces. In the following detailed figure description, reference is made to the accompanying drawings that form part of this description of the invention and are shown to illustrate specific embodiments by which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "front," "rear," "front," "rear," etc., is used in reference to the orientations of the figure(s) described. Since components of embodiments may be positioned in several different orientations, the directional terminology is for illustrative purposes and is not limiting in any way. It is understood that other embodiments may be used, and structural or logical changes may be made without departing from the scope of protection of the present invention. The following detailed description is not to be construed in a limiting sense. In the context of this description, the terms "connected", "connected" as well as "integrated" are used to describe both a direct and an indirect connection, a direct or indirect connection as well as a direct or indirect integration. Unless otherwise indicated, the indefinite and definite articles refer not only to a single component but are to be understood as "at least one". The terminology includes the previously mentioned words, variations thereof, and similar meanings. It should also be understood that the terms "about," "substantially," and similar terms in connection with the dimensions and a property of a component of the invention do not describe the described dimension and property as a strict limit or parameter and do not exclude minor variations thereof which are functionally similar. At a minimum, description parts with numerical parameters also include variations of these parameters according to mathematical and manufacturing principles in the prior art, e.g., rounding, deviations and other systematic errors, manufacturing tolerances, etc. In the figures, identical or similar elements are given identical reference numbers where appropriate. Reference mark lines connect the reference mark to the part in question. An arrow, on the other hand, that does not touch a part refers to an entire unit to which it is directed. Incidentally, the representations in the figures are not necessarily to scale. Certain areas may be shown exaggeratedly large to illustrate details. Furthermore, the drawings may be strikingly simplified and do not include every detail that may be present in the practical embodiment. All features of the respective embodiment are disclosed independently of other features of the respective embodiment example. Likewise, the features mentioned above and the features described in further detail can each be used individually by the invention, or in any combination of several features. The embodiments shown and described are not to be understood as a conclusive list but rather have an exemplary character for the description of the invention. The Figures show: Figure 1 and isometric front view of the disconnected plug connector according to the invention with the male and female parts of the locking mechanism disconnected from one another; Figure 2 a front view of the connected locking mechanism in the unlocked position; and Figure 3 the front view according to figure 2 in the locked position; figures 2 and 3 both not including the inner member with the inserting section for reasons of better visualization. Figure 1 shows an isometric view of the disconnected plug connector 2, generally consisting of a male socket member 4 and a female receiving member 6. Both, the socket member 4 and the receiving member 6, are designed as sleeves with central openings to locate one or more cables (not shown) therein, the ends of the cables ending in the socket member 4 and the receiving member 6 to be electrically connected to one another when the plug connector is locked or connected. Hence, in this embodiment, the socket member 4 constitutes the inner sleeve comprising an inserting section 4.1 with a smaller outer diameter than an abutment flange 4.2 located at the distal end of the inserting section 4.1. The inserting section 4.1 forms a cylindrical outer mating surface to be inserted into the receiving member 6. The receiving member 6 comprises an outer sleeve defining a receiving section with an outer circumferential periphery to at least partially receive the inserting section 4.1 of the socket member 4. The socket member 4, constituting the inner sleeve, comprises a distal end oriented away from the connection surface between the socket member 4 and the receiving member 6, defining a closed periphery or closed ring and a number of elastic arms extending proximally in a direction away from the closed ring. These elastic arms define the mating surface to mate with the inserting section 4.1 of the socket member 4. Located on the outside of the receiving member 6 is a rotatable locking ring 8 circumferentially enclosing the outer side of the receiving member 6. The elastic members provided on the receiving member 6 form 2 groups of respectively interchanging elastic members / arms, a release group 6.1 and the locking group 6.2 (for clarity, only one of each group is indicated with a reference number). As shown in figures 2 and 3, the elastic members or arms of the release group 6.2 are less wide or extend less radially outwards with respect to the central axis of rotation A than the locking group 6.2. The locking ring 8 encloses the outer periphery of the receiving section in the installed state and is relatively rotatable about the longitudinal central axis A. The locking ring 8 defines a circumferential locking surface on an inner locking side. This circumferential locking surface, again, comprises 2 sets of interchanging surfaces or defines two sets of interchanging surfaces, a longer set 8.1 and does shorter set 8.1, meaning that the longer set 8.1 extends further radially in the direction of the central axis A than the shorter set 8.2. By designing the fitting system between the receiving member 6 and the locking ring 8 accordingly, turning the locking ring 8 with respect to the then stationary receiving member 6 in figure 2 allows for the locking group 6.2 of elastic members to deflect radially outward with respect to the central axis A, therewith allowing relative movement of the socket member with respect to the receiving member and therefore connection and disconnection of the plug connector. When turning the locking ring 8 clockwise from the position shown in figure 2 to the position shown in figure 3, the longer set of locking surfaces 8.1 on the locking ring rests outside of the locking group of the receiving member so that the locking group 6.1 of the elastic arms are pressed radially inwards towards the central axis A, therewith locking the socket member 4 (not shown) inside the receiving member 6 by a friction fit and therewith locking the plug connector in the connected state for transmitting current from the cables located inside the plug connector. Reference Numbers A Central Axis of rotation 2 Plug connector 4 Socket member 4.1 Inserting section 4.2 Abutment flange 6 Receiving member 6.1 Release group 6.2 Locking group 8 Locking ring 8.1 Longer Group 8.2 Shorter Group
Claims
1. Plug connector for connecting two mating ends of a cable to one another for a current to flow in a connected state and to discontinue the current or fluid to flow in an unconnected state in which two complementary designed mating parts of the plug connector are disconnected from one another,the plug connector comprisingan inner sleeve comprising an inserting section,an outer sleeve comprising a receiving section defining an outer circumferential periphery to at least partially receive the inserting section of the inner sleeve,the receiving section defining a mating surface to mate with the inserting section of the inner sleeve,wherein a locking sleeve is provided relatively rotatable on the outer sleeveand wherein the inner sleeve and the outer sleeve are designed in such a manner that rotation of the locking sleeve with respect to the outer sleeve changes the mating surfaces from a clearance or transition fit, allowing the inner sleeve to be moved relatively to the outer sleeve, to an interference fit, not allowing relative movement of the inner sleeve with respect to the outer sleeve.
2. Plug connector according to claim 1, whereinthe receiving section defines an outer circumferential periphery with elastic members,the elastic members forming two groups of interchanging members,a release group and a locking group,wherein the release group extends less radially outwards with respect to a central axis of rotation than the locking group,wherein a locking sleeve or ring encloses the outer periphery of the receiving section and is relatively rotatable about a longitudinal axis and comprises a circumferential locking surface on an inner locking side,the circumferential locking surface comprising two sets of interchanging surfaces,a longer set and a shorter set, the longer set of locking surfaces extending further radially towards the longitudinal axis () than the shorter locking set of locking surfaces.
3. Plug connector according to claim 2, whereinthe elastic members being designed as cantilevered arms.
4. Plug connector according to claim 2, wherein the elastic members are integrally formed on the inner sleeve.
Citation Information
Patent Citations
Test connector and test connector assembly
CN204216358U
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EP2776752B1
Locking connector
US20150155654A1
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US2636068A