The present disclosure relates to circular connectors for electrical contacts and methods for manufacturing, assembling, and using the same.
Various features of the embodiments described herein, together with advantages thereof, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows:
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate various embodiments of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
In various embodiments, a circular connector can include a first shell that houses at least one electrical contact, a second shell that houses at least one corresponding electrical contact, and a coupling nut that is configured to secure the first shell and the second shell together to physically connect and electrically couple the electrical contacts housed within the shells. When the first shell and the second shell are assembled together, rotation of the first shell relative to the second shell can be limited and/or prevented. For example, the first shell and the second shell can include alignment features, which prevent rotation of the first shell relative to the second shell. It may be desirable to prevent rotation of the first shell relative to the second shell to maintain the alignment of the electrical contacts and to avoid damage thereto.
In various instances, as the coupling nut rotates in a coupling direction relative to the second shell, the coupling nut can be configured to threadably engage a threaded portion on the first shell to draw the first shell toward the second shell. Moreover, rotation of the coupling nut relative to the second shell can be resisted by an anti-decoupling mechanism located intermediate the coupling nut and the second shell. Circular connectors can be used to connect a variety of different types of electrical contacts and can be used in various environments. When circular connectors are used in high vibration environments, for example, it may be desirable to incorporate an anti-vibration or anti-decoupling mechanism. For example, circular connectors for high-vibration environments may employ a spring-loaded detent and/or ratchet mechanism to prevent and/or limit undesirable rotation, and possible decoupling, of the connector components. Exemplary anti-decoupling mechanisms are described in U.S. Pat. No. 9,531,120 to Bates, III, et al., titled CIRCULAR CONNECTORS, which issued Dec. 27, 2016. U.S. Pat. No. 9,531,120 is incorporated by reference herein in its entirety.
In various instances, it can be desirable to use an anti-decoupling mechanism having improved durability and rotational resistance while being cost effective to manufacture and assemble. Assembling a reduced number of components can be an effective cost reduction strategy. Furthermore, reducing the number of components in an assembly, particularly the number of moving and/or impacted components, can improve the durability of the circular connector. While providing a durable and cost effective solution, the circular connectors described herein can also meet the requirements of MIL-DTL-38999M w/AMENDMENT 1, dated Jan. 26, 2017, including the coupling and decoupling torque requirements thereof. More specifically, the maximum engagement and disengage torque for a circular connector can be between 8 and 40 lbf-in and the minimum disengagement torque can be between 2 and 7 lbf-in depending on the size of the shells. For example, for a shell size number 9, the maximum engagement and disengagement torque can be between 8 lbf-in and the minimum disengagement torque can be 2 lbf-in.
A circular connector 100 and various components thereof are depicted in
The first shell 110 and the second shell 120 can each include a housing and electrical contacts can be housed therein. For example, the first shell 110 can include a first housing and at least one pin connection housed therein, and the second shell 120 can include a second housing and at least one socket connection housed therein, for example. When fully assembled, the circular connector 100 can physically connect and electrically couple the pin connection(s) housed within the first shell 110 to the socket connection(s) housed within the second shell 120. Additionally or alternatively, in certain instances, the first shell 110 can include at least one socket connection and the second shell 120 can include at least one pin connection. Exemplary electrical contacts 101, e.g. pins and sockets, are depicted in shells 110′ and 120′ of a circular connector 100′ in
As described in greater detail herein, the coupling nut 140 can be secured to one of the first shell 110 or the second shell 120, and can threadably engage the other of the first shell 110 or the second shell 120. Referring to
The circular connector 100 includes an anti-decoupling mechanism 150. The anti-decoupling mechanism 150 includes features on the second shell 120 and features on the coupling nut 140, which interact to increase friction between the components and resist relative rotation. For example, the anti-decoupling mechanism 150 includes a plurality of detent assemblies 152 housed at least partially in the second shell 120 and a grooved or toothed surface 154 in the coupling nut 140. The detent assemblies 152 are biased into frictional engagement with the grooved surface 154 to resist rotation between the second shell 120 and the coupling nut 140. Because rotation between the coupling nut 140 and the second shell 120 is restrained and/or controlled by the anti-decoupling mechanism 150, the circular connector 100 can resist the decoupling of the first shell 110 and the second shell 120 even when subjected to extreme conditions, such as high-vibration environments. More specifically, when the first shell 110 and the second shell 120 are connected, as described in greater detail herein, the shells 110, 120 may not be permitted to rotate independently, but rather, can rotate together. In such instances, restrained rotation of the coupling nut 140 relative to the second shell 120 corresponds to restrained rotation of the coupling nut 140 relative to the first shell 110 and, as a result, decoupling rotation of the coupling nut 140 relative to the first shell 110 is restrained via the engagement between the coupling nut 140 and the second shell 120. The anti-decoupling mechanism 150 is further described herein.
Referring primarily to
The second shell 120 includes a first end 122, a second end 124, and an attachment portion 125 positioned at and/or near the second end 124. The second shell 120 also includes an outer surface 123, an inner surface 121, and a central bore 132 defined by the inner surface 121 and extending along the central axis A1. The attachment portion 125 is configured to attach the second shell 120 to another structure and/or electrical device, for example. The attachment portion 125 is a threaded portion of the outer surface 123. In certain instances, the attachment portion 125 can include other fastening or attachment features, such as a bracket, screw holes, and/or apertures, for example.
In various instances, the first shell 110 and the second shell 120 can include alignment features configured to align the shells 110, 120 and the electrical contacts housed therein. Such alignment features can prevent relative rotation between the shells 110, 120. For example, the first shell 110 includes alignment features, or keyways, 118 (
Additionally or alternatively, the first shell 110 can include at least one rib and the second shell 120 can include at least one notch, for example. The reader will appreciate that various styles and/or arrangements of alignment features can be utilized to prevent rotation between the first shell 110 and the second shell 120 and that suitable variations are applicable to the circular connectors described herein.
In certain instances, a biasing sleeve can be positioned around the second shell 120. The ends of the biasing sleeve can be connected by a clip, such that the biasing sleeve is securely positioned around the second shell 120. For example, the biasing sleeve can be positioned around the second shell 120 intermediate the alignment features 128 and an annular flange 126 of the second shell 120 that houses the detent assemblies 152. When the first shell 110 and the second shell 120 are assembled, the biasing sleeve can be positioned therebetween and can frictionally engage the first shell 110 and the second shell 120 to further prevent and/or limit relative movement between the first shell 110 and the second shell 120. A biasing sleeve can be comprised of metal, such as a beryllium copper alloy, for example. In other instances, a biasing sleeve can be comprised of additional and/or different metallic materials and/or non-metallic materials. Exemplary biasing sleeves are described in U.S. Pat. No. 9,531,120, which is incorporated by reference herein in its entirety.
Referring primarily to
The second shell 120 can also include at least one locking feature for securing the second shell 120 relative to the coupling nut 140. Such a locking feature can be configured to engage the coupling nut 140 to secure the second shell 120 relative to the coupling nut 140 while permitting rotation of the second shell 120 relative to the coupling nut 140. For example, a locking ring or retainer 160 intermediate the second shell 120 and the coupling nut 140 can be configured to hold the coupling nut 140 axially around the second shell 120 while permitting relative rotation therebetween.
Referring primarily to
When the coupling nut 140 and the second shell 120 are assembled, as in
Additionally or alternatively, the second shell 120 and the coupling nut 140 can be snap-fit together. A snap-fit connection can ensure that the coupling nut 140 is secured around the second shell 120 while rotation of the coupling nut 140 relative to the second shell 120 is permitted. For example, an annular or semi-annular feature of the coupling nut 140 can snap around a sloped locking rib on the second shell 120 to rotatably couple the coupling nut 140 to the second shell. Exemplary snap-fit arrangements are described in U.S. Pat. No. 9,531,120, which is incorporated by reference herein in its entirety.
The anti-decoupling mechanism 150 includes the detent assemblies 152 and the grooved surface 154. The geometric relationship between the detent assemblies 152 and the grooved surface 154 controls the rotational resistance provided by the anti-decoupling mechanism 150 and, thus, dictates the torques required to couple and decouple the circular connector 100. Referring primarily to
The second shell 120 includes a plurality of apertures or bores 129 defined radially into the outer surface 123 on a portion of the annular flange 126. The bores 129 are positioned intermediate the annular recess 127 and the first end 122. Each bore 129 houses a detent assembly 152 that includes a coil spring 151 and a ball bearing 153. Referring primarily to
The coil spring 151 is a cylindrical compression spring formed from a round metal wire, such as a stainless steel wire having a diameter of 0.0140 inches ±0.0004 inches, for example. The coil spring 151 is configured to exert an outward biasing force on the ball bearing 153 when the coil spring 151 is compressed. Referring primarily to
The four bores 129 are equidistantly-spaced around the perimeter of the annular flange 126. In other words, the bores 129 are rotationally offset by ninety degrees about the second shell 120. Moreover, the detent assemblies 152 are four-fold rotationally symmetric about the central axis A1 of the circular connector 100 and bilaterally symmetric about the mutually orthogonal axes A2 and A3.
The bores 129 can be machined into the second shell 120. For example, a drill or other cutting tool can cut the bores 129 into the second shell 120 from the outer surface 123. Because the bores 129 extend radially inward from the outer surface 123, manufacturing the second shell 120 and machining the bores 129 therein can be easier and, thus, more cost effective, than machining an outwardly extending bores from the inner surface 141 of the coupling nut 140, for example.
The coil springs 151 bias the ball bearings 153 radially outward into engagement with the grooved surface 154 on the inside of the coupling nut 140. Friction between the ball bearings 153 and the grooved surface 154 is configured to resist rotation of the coupling nut 140 relative to the shells 110, 120. The grooved surface 154 extends along an annular or ring-shaped track portion of the inner surface 141 within the coupling nut 140. The grooved surface 154 includes a plurality of axial grooves or teeth 155 defined around the radius of the coupling nut 140. The axial grooves 155 undulate inward and outward radially around the inner surface 141 of the coupling nut 140 and extend along axial paths or tracks through the coupling nut 140.
Referring primarily to
Each arced profile 158 defines an entry portion 158A and an exit portion 1586. The entry and exit portions 158A and 1586 correspond to a coupling rotation of the coupling nut 140. For example, when the coupling nut 140 is rotated in a coupling direction, e.g. clockwise (“CW”), the ball bearing 153 enters the axial groove 155 along the entry portion 158A and exits the axial groove 155 along the exit portion 158B. In other instances, the entry and exit portions 158A and 1586 can correspond to a decoupling rotation, e.g. counterclockwise (“CCW”) of the coupling nut 140. The entry portion 158A and the exit portion 158B of each axial groove 155 are bilaterally symmetric about the inflection point 161 of the arced profile 158.
Referring still to
It is unexpected that the torque requirements can be satisfied with the smoothly contoured profile of the grooved surface 154. More particularly, owing to the complementary smoothness of both the grooved surface 154 and the ball bearings 153, it is unexpected that the anti-decoupling mechanism 150 can generate sufficient friction to produce the appropriate resistance and torque. Nonetheless, satisfactory torque is generated by the anti-decoupling mechanism 150. For example, the spring force can be selected to maintain suitable frictional engagement between the grooved surface 154 and the ball bearings 153. The complementary smoothness advantageously enables an operator to manually rotate the coupling nut 140 in both the coupling and decoupling directions.
The radius of curvature RA of the arced profiles 158 is greater than the radius of curvature RB of the ball bearings 153. For example, the radius of curvature RA of the arced profiles 158 is 0.011 inches greater than the radius of curvature RB of the ball bearings 153. In other instances, the difference can be greater than 0.011 inches or less than 0.011 inches. In certain instances, the radius of curvature RA of the arced profiles 158 can be 20-30% greater than the radius of curvature RB of the ball bearings 153. In other instances, the difference the radius of curvature RA of the arced profiles 158 can be less than 20% or more than 30% greater than the radius of curvature RB of the ball bearings 153.
Referring still to
The geometry of the grooved surface 154 and the axial grooves 155 thereof is configured to minimize wear to the coupling nut 140 and the second shell 120. For example, the axial grooves 155 define a smooth contoured surface that sufficiently resists rotation while managing the shock or impact between the ball bearings 153 and the grooved surface 154 as the coupling nut 140 rotates. For example, the anti-decoupling mechanism 150 can be comprised of metal components including the ball bearings 153 and the grooved surface 154. A metal-on-metal relationship may be prone to increased wear, which would reduce the durability of a circular connector. However, the metal-to-metal connection between the ball bearings 153 and the grooved surface 154 is configured to provide a coupling and decoupling relationship in which the components smoothly and manually engage each other to minimize shocks thereto and, thus, stresses in the components. Moreover, a user can smoothly rotate the coupling nut 140 relative to the shells 110, 120 to couple and decouple the circular connector 100.
The grooved surface 154 on the inner surface of the coupling nut 140 is four-fold rotationally symmetric about the central axis A1 of the circular connector 100 and bilaterally symmetric about the axes A2 and A3. The axes A1, A2, and A3 are mutually orthogonal axes. Moreover, the axial grooves 155 are equidistantly spaced around the inside perimeter of the coupling nut 140. In certain instances, the grooved surface is n-fold rotationally symmetric where n is the number of axial grooves 155 depending on the size of the circle connector 100. Because there are four detent assemblies 152 in the second shell 120, the grooved surface can be n4-fold rotationally symmetric. For example, referring primarily to
To assemble the circular connector 100, each detent assembly 152 is positioned within a bore 129 in the second shell 120. Assembly grease is used to hold the detent assemblies 152 within the bores 129. For example, assembly grease can coat a portion of the bore 129, coil spring 151, and/or ball bearing 153 to hold the detent assemblies 152 in place. The assembly grease is sufficiently lubricous and viscous such that it holds the coil springs 151 and the ball bearings 153 within the bores 129 during the assembly process. Moreover, the assembly grease can serve to lubricate the anti-decoupling mechanism 150 and interfaces thereof. For example, a high performance synthetic grease such as TRIBOLUBE®-2N can be used.
After the detent assemblies 152 are secured within the bores 129, the second shell 120 is positioned within the coupling nut 140. To hold the second shell 120 within the coupling nut 140, the locking ring 160 is disposed therebetween. In particular, the locking ring 160 is compressed within the annular recess 127 in the second shell 120 such that the perimeter of the locking ring 160 is reduced to less than the inside diameter of the coupling nut 140. For example, a funnel tool can be utilized to reduce the diameter of the locking ring 160 while the coupling nut 140 is positioned over the second shell 120.
Referring primarily to
Referring primarily to
In use, the coupling nut 140 can be rotated about the shells 110, 120. In particular, the alignment features 118 and 128 maintain alignment of the shells 110 and 120, while the coupling nut 140 rotates about the second shell 120 to threadably engage the first shell 110. In particular, the internal threads 146 on the coupling nut 140 are configured to threadingly engage the external threads 116 on the first shell 110. The coupling nut 140 can be rotated in a clockwise (“CW”) direction to couple the coupling nut 140 and the first shell 110. In other instances, the counterclockwise (“CCW”) direction can correspond to a coupling direction, and the clockwise direction can correspond to a decoupling direction. As the coupling nut 140 is rotated about the shells 110, 120, the grooved surface 154 is configured to ride along the detent assemblies 152. The detent assemblies 152 are subjected to a compressive force by the grooved surface 154 and the coil springs 151 thereof are compressed to accommodate the undulations of the grooved surface 154 as the coupling nut 140 is rotated. As the coupling nut 140 is rotated relative to the shells 110, 120, the anti-decoupling mechanism 150 is configured to generate feedback. For example, the anti-decoupling mechanism 150 can provide tactile and/or auditory feedback as the detent assemblies 152 click into engagement with the axial grooves 155.
The detent assemblies 152 act as detents which engage the grooved surface 154 to resist rotation of the coupling nut 140 relative to the shells 110, 120. For example, when the coupling nut 140 is rotated in a coupling direction, e.g. a clockwise direction, the ball bearings 153 move along the exit portions 1586 of the axial grooves 155, which compresses the coil springs 151 and generates increased friction and rotational resistance. From the exit portions 158B, the ball bearings 153 move along a face 159 and then down the entry portion 158A of an adjacent axial groove 155. The coil springs 151 bias the ball bearings 153 outward such that the ball bearings 153 spring into the axial grooves and rest at the apex or inflection point 161 thereof. A minimum torque is required to compress the coil springs 151 and move the ball bearing 153 along the exit portion 158B of each axial groove 155. The minimum torque can be obtainable by hand, e.g., by manually rotating the coupling nut 140 relative to the shells 110, 120. Similarly, when the coupling nut 140 is rotated in a decoupling direction, e.g. a counterclockwise direction, the ball bearings 153 move along the entry portions 158A of the axial grooves 155, which compresses the coil springs 151 and generates rotational resistance. From the entry portions 158A, the ball bearing 153 move along a face 159 and then down the exit portions 158B of the adjacent axial grooves 155. The coil springs 151 bias the ball bearings 153 outward such that the ball bearings 153 spring into the adjacent axial grooves and rest at the apex or inflection point 161 thereof. A minimum torque is required to compress the coil springs 151 and move the ball bearing 153 along the entry portion 158A of each axial groove 155. Because the axial grooves 155 define a uniform curvature from end to end such that the entry and exit portions 158A, 158B are bilaterally symmetric about the apex 161, rotation of the coupling nut 140 relative to the shells 110, 120 is restrained equally, or substantially equally, in the coupling and decoupling directions. More specifically, the coupling-to-decoupling torque ratio is 1:1 or substantially 1:1. In certain instances, the coupling torque can differ from the decoupling torque by less than 25%. For example, the coupling torque and decoupling torque can differ by 5% or 10%.
Numerous specific details are set forth herein to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. Well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. The reader will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and illustrative. Variations and changes thereto may be made without departing from the scope of the claims.
The terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”) and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more elements possesses those one or more elements, but is not limited to possessing only those one or more elements. Likewise, an element of a system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features.
Although various devices have been described herein in connection with certain embodiments, modifications and variations to those embodiments may be implemented. Particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined in whole or in part, with the features, structures or characteristics of one ore more other embodiments without limitation. Also, where materials are disclosed for certain components, in certain instances, other materials may be used. Furthermore, in certain instances , a single component may be replaced by multiple components, and/or multiple components may be replaced by a single component, to perform a given function or functions. The foregoing description and following claims are intended to cover all such suitable modification and variations.
While this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope of the disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles.
Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials do not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.