This invention generally relates to electrical component connectors and contacts. More particularly, the present invention relates to an inventive three point contact design that may be used to connect varied electrical components to circuit boards such that the components may be assembled or installed on the circuit board and removed from the board without the need for time consuming soldering and desoldering of the component leads. The inventive contacts use flexible integral spring elements and appropriate contact element shaping to ensure a solid electrical connection between the printed circuit board and the electrical component leads. With the use of the inventive spring contacts, components may be easily installed on a board and tested, and, if necessary, may later be removed or replaced without the need for time consuming soldering and desoldering of the component. The inventive contacts are designed to ensure sound electrical connection with component leads of different cross sections, shapes and sizes.
As the size of electrical components used in electronic circuitry continues to decrease in size, the density of circuitry placed on printed circuit boards increases. With these two trends, a decrease in overall size and an increase in circuitry density, the value of space or real estate on circuit boards has similarly significantly increased. In addition to the importance and value of space on the board, equally important is need to ensure sound electrical connections between the component leads, which are decreasing in size and structure, and the circuit board.
Another trend in the design and manufacture of circuit boards that kept pace with the complexity and number of circuits and components included on boards, is the need to test, and potentially replace, the fabricated circuits and installed components as they are fabricated or installed on the board and tested. The need to disassemble or replace components on circuit boards has become an important issue. For example, it is inefficient and costly to install a component on a board, to only find out, after the board assembly is complete, that the component is not functionally performing. The time and effort to disassemble, remove and replace the component is expensive and fraught with the potential for creating or causing additional problems in the circuit.
One aspect of this problem is exemplified with electrical components that are installed on a board by soldering of the component leads to the board contacts. The time and effort to install a component, solder the leads to the contacts, test the component and, if the component is not functionally operable, desolder the leads and replace the component is very inefficient and expensive. As noted, in each of the desoldering, disassembly, reassembly and resoldering steps, there is the potential for creating additional problems in the board fabrication.
The current designs for installing electrical components to a board are similar to integrated circuit sockets, where the electrical component leads are bent 90 degrees so that the lead may be inserted into the socket and soldered in place. Again, the soldering of the leads to ensure a sound electrical connection does not allow for quick or easy disassembly and removal of the component.
Accordingly, there remains a need for a device or contact that allows an electrical component to be easily installed onto a circuit board without the need for solder connections, that ensures sound electrical connections and paths between the component leads and the circuit board, that allows the component to be tested through the board electrical connections, and also allows the component to, if necessary, be easily removed from the board and replaced with the need for desoldering the component leads.
Such a device and contact would greatly increase the efficient assembly and fabrication of circuit boards necessary for mass production of electrical component packages used in various electronic devices.
In view of the shortcomings of the prior art, it is an object of the present invention to provide an electrical contact that allows an electrical component to be easily and quickly installed on a circuit board and has sound electrical connections between the component and the board without the need for soldering of the component leads to the board contacts. It is a further object of the present invention that the electrical contact allows an electrical component to be easily and quickly removed from a circuit board without the need for desoldering of the component leads or without damaging the board contacts.
To achieve this and other objects, and in view of its purposes, the present invention provides an electrical spring contact for use with varied electrical components, the spring contact comprising a body section, where the body section is attachable at one end to a circuit board; two arms attached to opposite sides of the body section, the two arms defining a separation between the arms; the two arms each having an elbow section extending each arm towards the opposite arm; and a center section attached to the body section between the two arms whereby an electrical component lead can be held by and between, and be in electrical contact with the center section and the two arms.
It is a further object of the present invention to provide an electrical spring contact for use with varied electrical components, the spring contact comprising a body section having a first and second end and two opposing sides, the body section being attachable at the first end to a circuit board; two arms attached to the opposing sides of the body section and extending away from the second end of the body section, the two arms defining a separation between the arms, the arms each having an elbow section such that the separation between the two arms is reduced downstream of the elbow sections; and a center section attached to the body section between the two arms whereby an electrical component lead can be held by and between, and be in electrical contact with the center section and the two arms.
It is a further object of the present invention to provide an electrical spring contact for use with varied electrical components, where the electrical spring contact can hold an electrical component lead having a diameter approximately in the range of 0.010 inches to 0.025 inches.
Another aspect of the present invention is an electrical component assembly, having at least one electrical component, the electrical component having at least one electrical lead, and the connector assembly comprising a housing into which the electrical component fits and is held; and at least one electrical spring contact held within the housing, said electrical spring contact comprising, a body section, the body section being attachable at one end to a circuit board; two arms attached to opposite sides of the body section, the two arms defining a separation therebetween, the arms each having an elbow section extending each arm towards the opposite arm; and a center section attached to the body section between the two arms whereby the at least one electrical component lead can be held by and between, and be in electrical contact with the center section and the two arms.
It is a further object of the present invention to provide an electrical contact assembly, having at least one electrical component, the electrical component having at least one electrical lead, the contact assembly comprising a first housing into which the electrical component fits and is held; a second housing; at least one electrical spring contact seated within the second housing, the electrical spring contact comprising, a body section, the body section being attachable at one end to a circuit board; two arms attached to opposite sides of the body section, the two arms defining a separation therebetween, the arms each having an elbow section extending each arm towards the opposite arm; and a center section attached to the body section between the two arms whereby the at least one electrical component lead can be held by and between, and be in electrical contact with the center section and the two arms.
These and other aspects of the present invention are set forth below with reference to the drawings and the detailed description of certain preferred embodiments. It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are not intended to be or should be considered restrictive of the invention.
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawing are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawings are the following Figures:
The present invention is directed to an electrical contact used to ensure sound electrical connections between an electrical component and a circuit board to which the electrical component is to be assembled. The present invention also is directed to an electrical contact assembly that is to be mounted to a circuit board, where the noted contact is used to make the electrical connection between the electrical component and the circuit board. Example electrical components that the electrical contact may be used with, and which are disclosed in detail herein, include, without limitation, laser pump and laser diodes packages.
The inventive electrical contact has three primary structural elements. The contact elements include a body section, two flexible arms and a center section. The shape and structure of the contact elements is designed such that each contact holds and forms a strong electrical connection with one lead of an electrical component to be assembled on the circuit board. As designed, the arms and center section of the electrical contact provide three separate current paths between the component lead and the circuit board.
A preferred embodiment of the inventive electrical contact 10, as shown in the
The arms 14 each have an elbow section 18 such that downstream of the elbow sections 18, the arms 14 extend towards each other as shown in
The structural shape of the center section 16, as shown in
As shown in
An additional feature of the present inventive electrical contact is the lead cavity 25 (formed by the arms 14 and the center section 16 and having an approximate triangular shape (see
An objective of all electrical contacts is to establish and maintain a sound electrical connection between the contact and the lead to which it is attached. The force exerted by the contact on the lead is one aspect of the electrical connection. It has been discovered for the preferred embodiment shown in
The selection of the forces applied to the component lead 31 by the contact 10, or more particularly, applied by the arms 14 and center section 16, may be made through design and selection of the flexibility or elastic characteristics for the center section 16 and the arms 14. In a preferred embodiment of the inventive three point contact, the elbow sections 18 may be fabricated to have a particular spring constant or force per distance elastic characteristic. That is, for a higher spring constant, a larger force will be imparted to the component lead 31 by the arm 14. Similar to making the arms 14 with particular flexible force characteristics, the center section 16 similarly could be made in whole or in part to have a design spring constant.
Spring constants approximately in the range of 20 to 150 grams per thousandths of an inch (grams/mil) have shown good force characteristics and provided sound electrical connections. While too low a spring constant may result in an insufficient force being applied by the contact arms 14 or the center section 16 to the component lead 31, the force characteristics should not be chosen to be excessive. If a very high spring rate is chosen such that very large forces are required to move the arms 14 to allow the component lead 31 into the lead cavity 25, the potential exists that the component lead may deform or material may be scraped away from the lead. For the typical electronics application, the component leads have a very small diameter, being approximately in the range of 0.010 to 0.025 inches. Moreover, the component leads, in certain applications are manufactured with a gold covering or plating. Accordingly, if the force characteristics of the contact are designed to be too high, the very small component leads may be deformed or damaged, which could adversely affect functional performance of the component and circuit.
One preferred embodiment of the inventive spring contact that has shown good force characteristics and strong electrical connections uses a higher spring constant for the center section 16 than for the arms 14. However, other equally effective embodiments use similar spring constant characteristics for both the center section 16 and the arms 14.
In addition to altering the spring constant or spring coefficient of the center section 16 or the arms 14 to select the appropriate force characteristics of the spring contact 10, the direction of the force imparted by the arms 14 to component lead 31 as shown in
In the preferred embodiment shown in
While different materials may be used from which to fabricate the spring constant, in one preferred embodiment, the contact 10 may be manufactured of a phosphor bronze material.
The present inventive three point spring contact may be used to connect many different electrical components, having at least one lead, to circuit boards. Simply by way of illustration, and not to be limiting, two particular embodiments of inventive electrical contact assemblies using the three point spring contact are disclosed below.
Laser Pump Contact Assembly Embodiment
One example of a component that may be interconnected to a circuit board by the spring contact of the present invention is an electrical laser pump . The laser pump has a plurality of cantilever component leads extending from either side of the laser pump in a butterfly like configuration. For this embodiment of the present inventive electrical contact assembly, the three point spring contacts are seated within a housing, and the laser pump component is similarly seated into a separate housing sized and shaped to accommodate the laser pump. FIGS. 8(a) and 8(b) respectively show perspective views of an embodiment of a laser pump assembly, in an exploded-unassembled condition, and an assembled configuration.
An embodiment of the housing 42 into which the spring contact is seated is shown in a perspective view in
Because in this laser pump embodiment, the component leads 31 and the top portion of the spring contact 10 are exposed, a housing cover 33 may be used to protect the leads 31 and the contacts 10. A preferred embodiment of a housing cover 33 which may be used with the disclosed laser pump package is shown in
To further ensure the laser pump leads 31 are protected and maintained in the preferred position in the contacts 10, the cover 33 may also have flexible clips 34 which engage with step catches 43 provided on the sides of the housing 42. FIGS. 5(a) and 6 show a side view and a cut away partial side view of the housing 42 and the catches 43.
As shown in more detail in FIGS. 8(a) and 8(b), the laser pump may be easily installed to a circuit board by pressing the laser pump into place in its housing 40, such that the component leads respectively engage the contacts 10 seated in the housing 42. Once in place, the cover 33 may be pressed into place over the housing 42 to protect the laser pump leads 31 and the contacts 10. If the laser pump needs to be removed or replaced, the cover 33 may be removed by squeezing the clips 34 towards each other to disengage each clip 34 from the catches 43. The laser pump 30 may then be lifted out of its housing 40 and the laser pump leads 31 are pulled away from the contacts 10.
Laser Diode Contact Assembly Embodiment
Another example of the present inventive electrical contact assembly using the inventive spring contact is for a laser diode. Similar to the above described laser pump assembly, the laser diode has multiple component leads 31 and, to ensure solid attachment to a circuit board, a housing sized and shaped to hold the laser diode.
As shown in
While the disclosed embodiment of a laser diode assembly shown in
In another preferred embodiment of the laser diode assembly, as shown in
As an alternative preferred embodiment for the laser diode housing 40 shown in
In yet another preferred embodiment, the electrical component may be completely covered and held in place by a cover section. Such a retaining cover 38 for a laser diode is shown in top and bottom perspective views in FIGS. 17(a) and 17(b). This preferred embodiment of a retaining cover extends the length of the laser diode and covers the component leads and spring contacts. As shown in
In one preferred embodiment, the cover 38 and housing 40 may have double sided adhesive (not shown) along the surfaces 39 where the cover 38 and housing 40 join. In another preferred embodiment, shown in
Similar to the above described laser pump assembly, the laser diode package shown in FIGS. 11, 13(a), 13(b), 16, 18 and 19 may be easily installed to a circuit board by pressing the laser diode into place in its housing 40. As pressed into place, the three laser diode electrical leads 31 respectively engage the contacts 10 also seated in housing 40. If at some time the laser diode needs to be removed or replaced, it may easily be lifted out of the housing 40 and the laser diode leads 31 accordingly pulled out of the contacts 10. As described, with a cover in place, the laser diode, component leads and spring contacts have added protection and are secured from unintentionally being dislodged due to shock or vibration.
Although the invention has been described with reference to exemplary embodiments, it is not limited thereto. For example, while disclosure of use of the inventive spring contact and contact assembly has been made for a laser pump package and laser diode package, the spring contact may also be used with other electrical components. Accordingly, it is intended to be and understood that the following claims should be construed to include other variants and embodiments of the invention which may be made by those skilled in the art as being within the true spirit and scope of the present invention.
This application is a continuation of U.S. application Ser. No. 09/747,608, filed Dec. 22, 2000, to be issued.
Number | Date | Country | |
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Parent | 09747608 | Dec 2000 | US |
Child | 10946198 | Sep 2004 | US |