Patent Grant
7309256
The present invention generally relates to a flat flexible cable, and more particularly, to a flat flexible cable including an overmold with integrally-formed sealing members.
Flexible flat cables are used to an increasing degree in automobile manufacture as a replacement for ordinary cable harnesses consisting of round conductors. Various advantages are gained during use of the flexible flat cable harnesses in contrast to round cable harnesses. By using rectangular conductors, greater amounts of current can be transferred in comparison with round conductors. Therefore, rectangular conductors may be smaller, without comprising performance. The result is a reduction in weight and space allocation for flexible flat cables.
Moreover, individual cable seals consisting of ribbed cables are commonly utilized as an acceptable method for sealing individual cables in wet areas of the automotive electrical distribution system (EDS). Typically, each cable is isolated and sealed to the round wire insulation by a seal crimp at the electrical interface terminal and then collectively received into an electrical connector. Sealing each individual cable is conventionally done through an automated process.
However, despite the advantages of flexible flat cables, they do not lend themselves to being sealed individually using the automated process referenced above. Currently, in order to individually seal flexible flat cables, each cable must be sealed using an adhesive or a sealant during a secondary process. Such methods may be cumbersome and may add material and labor cost to the manufacturing process.
The inventors of the invention have recognized these and other problems associated with the flexible flat wire cables. To this end, the inventors have invented a flat flexible cable assembly comprising a flat flexible cable including a substantially rectangular conductor; an overmold encapsulating a portion of the substantially rectangular conductor; and a sealing member integrally-formed with and extending from the overmold, wherein the sealing member encapsulates the substantially rectangular conductor to form a seal.
A method of manufacturing a flat flexible cable assembly comprising a flat flexible cable including a substantially rectangular conductor, the method comprising the steps of:
wherein the sealing member encapsulates the substantially rectangular conductor to form a seal.
In an exemplary embodiment, a flat flexible cable assembly may be used to connect electrical components (not shown) in “wet” areas of an automotive electrical distribution system (not shown). These “wet” areas are known in the industry, and may include, for example, parts of the engine where fluids are present.
Referring now to
The conductors 12 may be made from any conductive material, such as, for example, aluminum, copper, or the like. The insulating sheath 14 is known in the art, and may be manufactured from any number of materials. For example, the sheath 14 may be made of polymeric materials, such as polyvinylchloride (PVC), and the like. Factors to take into consideration when deciding upon the material properties of the insulating sheath 14 include, amongst others, the maximum operating voltage of the rectangular conductors 12 and the temperature of the environment where the flat cable assembly 10 may be located.
A terminal 18 that provides an electrical connection point is formed by stamping and forming in a progressive die. Attachment of the terminal is accomplished by stripping the insulating sheath 14 at one end of each conductor 12 and crimping, or welding the appropriate portion of the terminal to conductor 12. As illustrated in the embodiment, the flat flexible cable assembly 10 includes two conductors 12 and two terminals 18. However, it can be appreciated that the invention is not limited to the number of conductors 12 and terminals 18, and that the invention can be practiced with any desired number of conductors 12 and terminals 18.
Referring to
According to an aspect of the invention, the cable assembly 10 includes an overmold 26 that encapsulates a portion of the cable assembly 10 and includes one or more sealing members 28 integrally-formed with the overmold 26 that encapsulates each conductor 12 at the point it attaches to terminal 18 to form a seal for each individual conductor 12. Specifically, the overmold 26 and the one or more integrally-formed sealing members 28 are formed by using an overmold process. During the overmold process, the cable assembly 10 is placed within a mold tool (not shown) and the overmold material is introduced into the mold tool such that the overmold material covers a portion of the conductors 12 at the point it attaches to terminal 18 and also to cover a portion of the insulating sheath 14 proximate the stripped, bare conductors 12. Once the overmold material has been cured, the overmold 26 is positively secured to the insulating sheath 14 while having integrally-formed individual sealing members 28 encapsulating each conductor 12 that has been stripped of the insulating sheath 14. The sealing member 28 may be formed in a well-known manner by including a configuration (not shown) in the mold tool, which may be impressed into the tool, that allows each terminal 18 of the plurality of conductors 12 to be individually sealed by the sealing member 28 during the overmold process.
It can be appreciated that the overmold material used in forming the overmold 26 may be any flexible plastic molding material, such as a thermoplastic elastomer (TPE) material, and the like. Further, it can be appreciated that overmold 26 may also contain insulation properties, similar to electronically insulating sheath 14. As shown in
As described above, the overmold process serves a dual purpose: 1) to form the overmold 26 that is positively secured to the insulating sheath 14 of the flat flexible cable assembly 10, and 2) to form the individual sealing member(s) 28 that extend from the overmold 26 and encapsulate each conductor 12 to form an individual seal around each conductor 12.
As illustrated, the one or more sealing members 28 may comprise one or more ribs 30 that extend circumferentially from a central, tubular member 32. The tubular member 32 encompasses the conductors 12 and extends over a portion of terminals 18. In the illustrated embodiment, the ends of terminals 18 remain exposed. While three ribs 30 are shown, it can be appreciated that the invention can be practiced with any desired number of ribs 30 that are capable of providing an adequate seal for each conductor 12.
Referring now to
It can be appreciated that the invention can be practiced with the sealing member 28 having any desired shape or size, so long as sealing member 28 engages and seals the individual cavities 36 of the sealed connector 34 and provides an adequate seal. For example, the ribs 30 may be omitted and the sealing member 28 may have a diameter 40 approximately equal to, or may be slightly larger than the diameter 42 of each individual cavity 36 of the sealed connector 34.
The embodiments disclosed herein have been discussed for the purpose of familiarizing the reader with novel aspects of the invention. Although preferred embodiments of the invention have been shown and described, many changes, modifications and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of the invention as described in the following claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 4753005 | Hasircoglu | Jun 1988 | A |
| 4772231 | Hayes | Sep 1988 | A |
| 4776803 | Pretchel et al. | Oct 1988 | A |
| 4824394 | Roath et al. | Apr 1989 | A |
| 6132236 | Kozel et al. | Oct 2000 | A |
| 6612863 | Terai | Sep 2003 | B2 |
| 6875048 | Lee | Apr 2005 | B2 |
| Number | Date | Country | |
|---|---|---|---|
| 20070161289 A1 | Jul 2007 | US |
