Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS1749740 A
Publication typeGrant
Publication dateMar 4, 1930
Filing dateJun 10, 1926
Priority dateJun 10, 1926
Publication numberUS 1749740 A, US 1749740A, US-A-1749740, US1749740 A, US1749740A
InventorsFrederickson Otto A
Original AssigneeWiremold Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Insulated conductor
US 1749740 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)


This invention relates to a tubular braid adapted for use as a protecting jacket for electrical conductors.

There is an urgent demand "for insulated electrical conductors that can be supplied a very low cost. Such conductors are exten sively used in Wiring buildings for electric bell circuits and for other purposes Where a current of only a few volts is employed.

A rubber jacket applied to conductor Wires will insulate the Wires suficiently for use in circuits having a low voltage, but the rubber covering of an electrical conductor is easily damaged unless protected by an enclosing Wrapper, and in order to protect the rubber j achet of conductors it is customary to apply over the jacket a braided cotton cover.

Insulated conductors of the type above mentioned having a rubber j aclret protected by cotton braid are extensively used for many purposes Where a low voltage is eraployed and such conductors are used to some extent in electric light circuits.

The present invention relates to insulated. conductors of the type above mentioned, and more particularly to a braided. jacket which is Well adapted for use on such" conductors to protect the insulating rubber. Que or the primary features of the present invention resides in a braided jacket that is constructed entirely of twisted strands of paper. Such paper jacket can be manufactured at a very low cost and is also extremely tough and durable in use. I

Another feature of the invention resides in a braided jacket that is formed entirely oi twisted paper strands that are disposed in spaced relation to each other so that they produce an open braid having interstices between the strands of the braid. This open braid is in many cases desirable because of the rapidity with which it may be constructed and also oi the saving in material obtained by spacing the twisted strands apart.

The various features of the invention will be best understood from the following description when read in connection with the accompanying drawings; wherein,

Fig. 1 is a perspective View of an insulated lto. lllitl'lfl.

conductor covered with braid constructed in accordance With the present invention;

Fig. 2 is a transverse sectional vievv of Fig. l;

S is perspective View similar to Fig. l, but shows a modified type of braid.

Fig. is transverse sectional view of Fig, 3.

Although the braid forming the subjectmatter of the present invention is particular ly Well adapted for use as a protecting cover ing for the rubber jacket of a metallic elec= trical conductor it may be used for various purposes Where a tough, durable and inen pensive tubular braid is desired.

The n" allic conductor 10 is shown in the dravvingsasprovidedwith an insulating et ll formed of rubber or otherfsuitable new terial the jacket 11 is protected by covering of braid constructed in accordance With the present invention. The b aided covering shown in Figs. 1 and 2 is formed of series of strands 12 of twisted paper that extend spirally about the conductor in one direction and these strands are interbraided with the series of strands 13 of twisted paper that extend spirally about the conductor in the opposite direction.

The s -unds 1% are preferably positioned in spaced relation to each other, and the same is true the strands 18, so that-an open braid is formed having interstices between the adjacent strands. This construction is desirable in many cases because of its econo my of production due to the saving of material and rapidity With which the strands can he braided many cases it is desirable to treat the paper strands "l2 and 13 with a moisture proofing material so that the strands will not rot or deteriorate upon exposure to moisture, and a Wan-like substance such as paraffine havin lubricating qualities is preferably employed the moisture proofing ma terial, because the appl cation of paratiine to the paper strands materially increases the speed which they may be braided, since the parafine irn a smooth surface to the pager which enables it to be delivered smoothly to the braiding point by the braiding machine at high speed.

if desired the interstices or apertures formed in the open braid may be filled .up b applyin any suitable coating material suc as ara ne or stearin pitch to the finished braid, so that it will lie in the interstices as indicated by 14.

The braid shown in Figs. 3 and 4 differs from that disclosed in Figs. 1 and 2 in that in the modified construction the twisted strands of paper 15 that extend in one direction are larger in diameter than the twisted strands of paper 16 that extend in the opposite direction; the strands 15 however are shown as disposed in spaced relation to each, as are also the strands 16, so that openings or interstices are formed between the stran s 15 and 16 of the braid, as in Fig. 1.

From the foregoing it will be seen that an open braid constructed entirely of paper in accordance with the present invention will, form a tough, durable protecting jacket for an insulated conductor, and that the braid can be produced rapidly and at low cost.

What is claimed is An article of manufacture comprising, in combination, an electrical conductor, a surrounding sheath of insulating material, a protecting jacket formed about said sheath and comprising an open tubular braid of light weight formed of a series of parafiin treated, twisted strands of paper that extend spirally about said sheath 1n one direction in spaced relation to each other and in terbraided with a series of parafiin treated, twisted strands of paper that extend spirally about the sheath in the opposite direction in s aced relation to each other to form a tough, durable, open braid produced entirely of paper and having relatively large interstices between the strands, and a fillin compound de osited in the interstices to orm a wall of insulation compoundi'surrounding said sheath and which is protected from mechanical injury by the 0 en braid.

In testimony whereof, I ave signed my name to this s ecification.


iamhiimfl-asm 11,-... namaamm i

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2454625 *Apr 9, 1947Nov 23, 1948Bondon Lewis AInsulated electrical conductor and method of fabricating the same
U.S. Classification174/121.00R
International ClassificationH01B7/18
Cooperative ClassificationH01B7/1865
European ClassificationH01B7/18M