BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an assembled, perspective view of a cable assembly in accordance with the first embodiment of the present invention;
FIG. 2 is an exploded, perspective view of the cable assembly of FIG. 1;
FIG. 3 is a partially assembled view of the cable assembly in accordance with the first embodiment of the present invention;
FIG. 4 is another partially assembled view of the cable assembly in accordance with the first embodiment of the present invention;
FIG. 5 is a partially assembled view of a cable assembly in accordance with the second embodiment of the present invention;
FIG. 6 is an assembled view of the cable assembly of FIG. 5;
FIG. 7 is a partially assembled view of a cable assembly in accordance with the third embodiment of the present invention; and
FIG. 8 is an assembled view of the cable assembly of FIG. 7.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiment of the present invention.
Referring to FIGS. 1-2, a cable assembly 100 in accordance with the first embodiment of the present invention comprises a pair of terminals 1, a cable 3 electrically connecting with the terminals 1 and a strain relief device 20 molded at an end of the cable 3.
Referring to FIGS. 3-4 in conjunction with FIGS. 1-2, the cable 3 comprises a center wire 31, a metal braiding 32 enclosing the center wire 31 and a jacket 35 shrouding the metal braiding 32. The strain relief device 20 comprises a first plastic layer 4 pre-molded over an end of the cable 3 with the forward end of the cable 3 exposed beyond the first plastic layer 4 and a second plastic layer 2 over-molded on the first plastic layer 4. The forward end of the jacket 35 is decorticated and the inner metal braiding 32 is exposed outside. The exposed metal braiding 32 is collected together to form into a narrow strip with a heated-shrinking insulative tube 33 enclosed the front part of the exposed metal braid 32 thereon with forward ends of the metal braiding keeping exposed status, with the rear part of the exposed metal braiding 32 just exposed outside. The front part of the exposed metal braiding 32 together with the heated-shrinking insulative tube 33 servers as a second wire 34. The second wire 34 is used for transmitting negative electricity, while the center wire 31 is used for transmitting positive electricity. The first plastic layer 4 is partially pre-molded over part of the center wire 31, part of the second wire 34, the rear part of the exposed metal braiding 32 and the jacket 35 nearby the rear part of the metal braiding 32. The first plastic layer 4 is a kind of high-density plastic material, such as a high-density polyvinyl chloride (PVC 35P). The second plastic layer 2 is over-molded on the outside of the first plastic layer 4 and the jacket 35 of the cable 3 nearby. The second plastic layer 2 is other kind of low-density plastic material, and a low-density polyvinyl chloride (PVC 60) may be a good choice. A slotted-shape fixing portion 21 is formed on the outside of the second plastic layer 2, thus, the cable 3 can be connected to an electrical device (not shown) reliably.
When manufacturing the cable assembly, firstly, the jacket 35 of the cable 3 is partially stripped from the inner metal braiding 32, with the metal braiding 32 exposed outside. Secondly, the exposed metal braiding 32 is peeled off the center wire 31 and collected together to form into a strip with the heated-shrinking insulative tube 33 partially enclosed thereon. Thirdly, the heated-shrinking insulative tube 33 is heated to combine the metal braiding 32 with the heated-shrinking insulative tube 33 together to serve as the second wire 34. Fourthly, the first plastic layer 4 is pre-molded over the center wire 31, the second wire 34, the exposed metal braiding 32 and the jacket 35 adjacent to the exposed metal braiding 32. Fifthly, the second plastic layer 2 is over-molded on the first plastic layer 4 and the jacket 35 adjacent to the first plastic layer 4. The center wire 31 and the second wire 34 can electrically connect with the terminals 1 via soldering or crimping.
The cable assembly of the second embodiment of the present invention is same as the first embodiment of the present invention cable assembly 100 except for a position where a first plastic layer 4′ is pre-molded over, and other same structures or manufacturing process are omitted hereinafter. Referring to FIGS. 5-6, the exposed metal braiding 32 consists of a first section 32′ of the metal braiding 32 being peeled off the center wire 31 and a second section 32″ of the metal braiding 32 just staying on the outside of the center wire 31. The first section 32′ of the metal braiding 32 is collected together to form into a strip with a heated-shrinking insulative tube 33 enclosed thereon. The heated-shrinking insulative tube 33 is heated and the first section 32′ of the metal braiding 32 and the heated-shrinking insulative tube 33 are combined together to serve as the second wire 34. Then, the first plastic layer 4 is pre-molded over the center wire 31, the second wire 34, the second section 32″ of the metal braiding 32 and the jacket 35 adjacent to the second section 32″ of the metal braiding 32. As the second section 32″ of the metal braiding 32 is stayed on the outside of the center wire 31, and the first plastic layer 4′ directly attaches to the outer periphery of the second section 32″ of the metal braiding 32. Thus, the second section 32″ of the metal braiding 32, the jacket 35 adjacent to the second section 32″ of the metal braiding 32 and the first plastic layer 4′ may be combined together better.
The cable assembly of the third embodiment of the present invention is also same as the first embodiment of the present invention cable assembly 100, except for a position where a first plastic layer 4″ is pre-molded over, and other same structure or manufacturing process is omitted hereinafter. Referring to FIGS. 7-8, the exposed metal braiding 32 consists of a first section 32′ of the metal braiding 32 being peeled off the center wire 31 and a second section 32″ of the metal braiding 32 just staying on the outside of the center wire 31. The first section 32′ of the metal braiding 32 is collected together to formed into a strip with the heated-shrinking insulative tube 33 enclosed thereon. The heated-shrinking insulative tube 33 is heated and the first section 32′ of the metal braiding 32 and the heated-shrinking insulative tube 33 are combined together to serve as the second wire 34. Then, the first plastic layer 4″ is pre-molded over outer periphery the second section 32″ of the metal braiding 32 and the jacket 35 adjacent to the second section 32″ of the metal braiding 32. The manufacturing process may be easier as the first plastic layer 4″ is just pre-molded over the second section 32″ of the metal braiding 32 and jacket 35.
When using the cable assembly 100, the terminals 1 are connected to an electrical device (not shown), however, it should be known that the center wire 31 and the second wire 34 may be directly electrically connecting with the electrical device without the terminals 1. The cable 3 is positioned on the electrical device via the engagement between the fixing portion 21 formed on the second layer of plastic 2 and corresponding fixing portion (not shown) formed on the electrical device. When a customer moves the electrical device, the cable 3 may swing along substantially cone-shaped trace, as the metal braiding 32 and the jacket 35 of the end of the cable 3 are combined together by the first plastic layer 4, and there is no relative movement between the metal braiding 32 and the jacket 35 of the end of the cable 3, thus, a torsion originally acted on a connection portion between the cable 3 and the electrical device when there is no such strain relief device 20 is shifted to an end 22 of the second plastic layer 2, and the torsion is reduced or eliminated.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrated only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Patent Application
20070251724
