Patent Application
20100203774
For industrial applications electrical components are commonly mounted on rails inside equipment racks. The mounting rails often have an industry-standard configuration, such as, for example, the DIN rail. DIN rails have a top-hat cross section that includes a middle section between two edge flanges. One standard DIN rail has a 35 mm width. In use, electrical components are clamped to the edge flanges and span the middle section. To facilitate mounting to various rail configurations, electrical components are often designed to be mounted to a rail adapter that is appropriately dimensioned for a specific rail. The rail adapter includes a back plate having mounting features for the electrical component and a rail connection mechanism that is configured to connect the rail adapter, and the electrical component it carries, to the rail.
In one embodiment, a rail adapter is provided for connecting an electrical component to a mounting rail having two spaced elongate mounting flanges on either side of an elongate middle portion. The rail adapter includes a back plate and a wire spring clip. In one example embodiment, the back plate also includes a fixed rail mounting feature configured to engage a first of the two mounting flanges to connect the first mounting flange to the back plate. The back plate may also include one or more spring clip mounting features, and a spring stop.
The wire spring clip is moveably retained in the one or more spring clip mounting features. The wire spring clip is configured to be moved relative to the back plate between an engagement position in which the wire spring clip captures a second of the two mounting flanges between the wire spring clip and the back plate and a release position in which the wire spring clip is released from the second mounting flange. The wire spring clip is made of a length of wire shaped to form a connection portion and a spring portion. The connection portion is configured to capture the second mounting flange against the back plate when the wire spring clip is in the engagement position. The spring portion is configured to co-act with the one or more spring stop features to urge the wire spring clip towards the engagement position.
In one particular embodiment, the connection portion includes two ears spaced apart from one another. Each ear is configured to overlay the second mounting flange and capture the second mounting flange against the back plate when the wire spring clip is in the engagement position. In this embodiment the spring portion includes a flat spring formed by a portion of the length of wire spanning between the two ears. The flat spring contacts the spring stop at a longitudinal side between the ears when the wire spring clip is in the release position such that the flat spring flexes against the spring stop away from a relaxed position and urges the wire spring clip back toward the engagement position.
In one embodiment, a method is provided that connects an electrical component to a mounting rail having two spaced elongate mounting flanges on either side of an elongate middle portion. The method includes connecting the electrical component to a back plate and fixing a first of the two mounting flanges to a fixed rail mounting feature on the back plate. A force is applied to a wire spring clip that is moveably retained on the back plate. The wire spring clip includes a length of wire shaped to form a connection portion and a flat spring. The connection portion is configured to capture the second mounting flange against the back plate when the wire spring clip is in an engagement position. The flat spring is configured to flex against one or more spring stop features and to provide a biasing force that urges the wire spring clip towards the engagement position.
The force is sufficient to overcome the urging of the spring portion toward the engagement position and to move the wire spring clip to a release position such that the connection portion is not positioned to overlay the second of the two mounting flanges. The second mounting flange is placed against the back plate; and the force on the wire spring clip is released so that the biasing force of the flat spring moves the wire spring clip to the engagement position so that the connection portion captures the second mounting flange against the back plate.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate various example systems, methods, and other example embodiments of various aspects of the invention. It will be appreciated that the illustrated element boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. One of ordinary skill in the art will appreciate that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of another element may be implemented as an external component and vice versa. Furthermore, elements may not be drawn to scale.
The back plate 15 includes two slider clip mounting flanges 17. The slider clip 20 is slideably retained in these mounting flanges 17 and is free to move along the back plate toward and away from the tabs 19. The slider clip 20 rides on two clip rails 24 that are configured to engage a second mounting flange of the mounting rail when the slider clip 20 is moved toward the tabs 19. The clip rails 24 release the second mounting flange when the slider clip 20 is moved away from the tabs 19. A compression spring 30 is coupled between the slider clip 20 and the back plate 15. The compression spring 30 provides a biasing force on the slider clip 20 relative to the back plate 15 that tends to urge the slider clip toward the tabs 19 and into engagement with the second mounting flange when a second mounting flange is present. As can be seen from
The wire form spring clip 70 is made of a length of wire 70 that is bent to form several features. In some embodiments it is possible to form the features without hard tooling by using, for example, a CNC wire bending machine. The wire form spring clip 70 includes at least one connection portion that is configured to capture the mounting flange against the back plate 55. In the illustrated embodiment, the connection portion is a pair of ears 76 that are formed into the length of wire 71. As can also be seen in
In the embodiment illustrated in
The wire form spring clip 70 shown in
In the illustrated embodiment, the back plate 55 is made from stamped metal having a thickness of approximately 0.050 inches. However, any suitable material may be used. The back plate 55 includes connection portion guides that constrain motion of the connection portions with respect to the back plate 55. In the illustrated embodiment, the connection portion guides are ear guide flanges 61 that are formed by bending cut out portions of the back plate 55 upward to a perpendicular orientation with the rest of the back plate. The ear guide flanges 61 include a central opening through which the ear 76 protrudes. The ear guide flanges 61 constrain motion of the ears 76 away from the back plate and thereby limit motion of the wire form spring clip 70 to motion parallel to the back plate.
In the illustrated embodiment, the spring stop 67 is formed by bending a cut out portion of the back plate 55 to form a finger that projects perpendicularly from the back plate and curls over at its distal end to surround the wire 71. The wire form spring clip 70 contacts the spring stop 67 when the wire form spring clip 70 is moved away from the mounting flange. Flexure of the flat spring 78 against the spring stop 67 allows the wire form spring clip 70 to release the mounting flange.
Other back plate features that interact with the wire form spring clip 70 include spring limiters 65 and an end guide flange 66. The spring limiters 65 limit motion of the wire form spring clip 70 away from the mounting flange. The spring limiters 66 thus may prevent over-flexing of the flat spring 78 that could damage or destroy the flat spring. The end guide flange 66 in conjunction with the rest of the back plate forms a channel through which the extension portion may travel parallel to the back plate while having limited motion away from the back plate.
The back plate 55 includes component mounting features in the form of mounting holes 63. The mounting holes 63 can be used to mount any number of electrical components, such as, for example, circuit breakers, terminal blocks, relays, timers, or contactors, to the rail adapter 50. Of course, other mounting features, such as snap fit features or adhesives may be used to connect the electrical component to the rail adapter. The back plate also includes a rail mounting tab 69a, 69b that are formed by bending cut out portions of the back plate upward to create a channel into which the first mounting flange may be inserted. The rail mounting tabs 69a hold the rail from moving laterally while the rail mounting tab 69b holds the rail against the back plate 55. As can be seen from
As can be seen from the above description a wire form rail adaptor includes wire form spring clip that incorporates both a connection portion and a spring portion formed from a length of wire. This wire form spring clip thus performs two functions, connection and biasing, with a single part.
The following includes definitions of selected terms employed herein. The definitions include various examples and/or forms of components that fall within the scope of a term and that may be used for implementation. The examples are not intended to be limiting. Both singular and plural forms of terms may be within the definitions.
References to “one embodiment”, “an embodiment”, “one example”, “an example”, and so on, indicate that the embodiment(s) or example(s) so described may include a particular feature, structure, characteristic, property, element, or limitation, but that not every embodiment or example necessarily includes that particular feature, structure, characteristic, property, element or limitation. Furthermore, repeated use of the phrase “in one embodiment” does not necessarily refer to the same embodiment, though it may.
While example systems, methods, and so on have been illustrated by describing examples, and while the examples have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the systems, methods, and so on described herein. Therefore, the invention is not limited to the specific details, the representative apparatus, and illustrative examples shown and described. Thus, this application is intended to embrace alterations, modifications, and variations that fall within the scope of the appended claims.
To the extent that the term “includes” or “including” is employed in the detailed description or the claims, it is intended to be inclusive in a manner similar to the term “comprising” as that term is interpreted when employed as a transitional word in a claim.
