Claims for Patent: RE31081

Summary for Patent: RE31081

Title:	Railroad switch heater
Abstract:	An apparatus for heating railroad rails such as those forming a railroad switch to prevent obstruction of the switch by ice and snow includes an elongate, bendable, high temperature heating cable disposed lengthwise against and along a side of the rail web. The cable comprises an electrical resistance heating wire encased in a high temperature resistant electrically insulating material confined inside a thermally conductive deformable metal sheath. An elongate, pliable heat insulating mat is disposed lengthwise against and along a length of the cable and portions of the rail web laterally adjacent thereto to prevent heat losses by convection or radiation from the cable length. An elongate substantially rigid casing member is fitted lengthwise over the mat and bears against the web side to confine the mat in place, and is held tightly in place against the rail web. Current is supplied at high .[.wattage.]. .Iadd.watt density .Iaddend.through the resistance wire of the cable, generating heat which flows into the rail and through it and switch plates to a movable switch rail efficiently by conduction.
Inventor(s):	Keep, Jr.; Henry (Madison, CT)
Assignee:
Application Number:	06/240,582
Patent Claims:	1. Apparatus for heating a railroad rail comprising: an elongate, bendable, high temperature heating cable disposed lengthwise against and along a side of the rail web, said cable comprising an electrical resistance heating wire encased in high temperature resistant electrically insulating material confined inside a thermally conductive deformable metal sheath, an elongate, .[.pliable,.]. heat insulating mat disposed lengthwise against and along a length of said cable and portions of said web laterally adjacent thereto to prevent heat losses by convection or radiation from said cable length, said mat comprising an elongate mass of high temperature resistant ceramic fiber insulation confined .[.in a flexible sleeve.]. .Iadd.by means .Iaddend.that prevents fiber of said mass from creeping between said cable and the rail, an elongate, substantially rigid casing member fitted lengthwise over said mat and bearing against said web side to confine said mat in place, means holding said casing member .Iadd.and thereby said mat and said cable .Iaddend.tightly in place against the rail web; and means for supplying current at high .[.wattage to.]. .Iadd.watt density through .Iaddend.said wire; whereby the rail along said cable length is heated efficiently by conduction, yet burn-out of said cable is prevented, during heating of said cable by said current. 2. The apparatus of claim 1, said .Iadd.insulation confining means comprising a flexible .Iaddend.sleeve .[.being.]. formed of a high temperature resistant wire mesh. 3. The apparatus of claim 1, said cable being supported in proper position by hooks .[.engaged on the inner side of.]. .Iadd.fastened to and extending inward from .Iaddend.said casing member at intervals therealong. 4. The apparatus of claim 1, said cable comprising as said wire a single, central strand of chromium-nickel electrical resistance alloy, as said insulating material a plurality of layers of ceramic or silica fibers braided onto said strand, and as said sheath a heat and oxidation resistant metal armor braided onto and about the outermost of said layers. 5. The apparatus of claim 4, .Iadd.wherein .Iaddend.said strand, said layers and said armor are constructed and assembled to linearly expand at substantially the same rate. 6. The apparatus of claim 4, said armor being braided of copper-nickel alloy wires. 7. The apparatus of claim 1, said casing member being of sheet metal and of substantially U-shaped cross-section that encloses said mat and the side walls of which bear along their edges against said web side. 8. The apparatus of claim 7, said holding means comprising a spring clip having a first section embracing the base flange of the rail and a second section bearing resiliently against a front wall of said casing member to hold the casing member against said rail web. 9. Apparatus according to claim 1, for heating a railroad rail supported laterally along a reach of said web side by a series of rail braces spaced therealong, said cable .Iadd.being .Iaddend.disposed against said web side along each region thereof between adjacent braces, each said length of said cable having a said insulating mat disposed against and along it as aforesaid with a said casing member fitted over the mat and held against the rail as aforesaid, said cable in the vicinity of each said brace being bent upwardly and over the brace from ends of the casing members adjacent to the brace. 10. Apparatus for heating a railroad rail switch that includes two fixed rails and two switch rails movable laterally to and away from the fixed rails on underlying switch plates and interconnected by switch tie rods, said apparatus comprising: an elongate, bendable, high temperature heating cable having a first portion disposed along the outer side of one fixed rail, second portions connected in series with said first portion, extending from the outer side of said one fixed rail toward and back from the other fixed rail under said rails in the region of each of said tie rods, and a third portion connected in series with said first and second portions disposed along the outer side of the other of said fixed rails, each said cable portion comprising an electrical resistance heating wire encased in high temperature resistant electrically insulating material confined inside a thermally conductive deformable metal sheath; an elongate, .[.pliable.]. heat insulating mat disposed lengthwise against and along a length of each of said first and third portions of said cable disposed along the outer side of a fixed rail and disposed against portions of the rail web laterally adjacent said first and third cable portions to prevent heat losses by convection or radiation from the cable length, each said mat comprising an elongate mass of high temperature resistant ceramic fiber insulation confined .[.in a flexible sleeve of high temperature resistant wire mesh.]. .Iadd.by means .Iaddend.that prevents fiber of said mass from creeping between the cable and said rail web; an elongate, substantially rigid, sheet metal casing member fitted lengthwise over and enclosing each said mat, and bearing along the edges of its side walls against said wall rail web to confine the mat in place; means holding each said .[.channel.]. .Iadd.casing .Iaddend.member .Iadd.and thereby said mat and said cable .Iaddend.tightly in place against the related rail web; and means for supplying current at high .[.wattage to.]. .Iadd.watt density through .Iaddend.said wire of each said cable; whereby said fixed rails along said cable lengths and consequently said switch plates and said switch rails are heated efficiently by conduction and said tie rods are heated by radiation and convection, yet burn-out of said cables is prevented, during heating of said cables by said current. 11. The apparatus of claim 10, said holding means comprising for each said .[.channel.]. .Iadd.casing .Iaddend.member a spring clip having a first section embracing the base flange of the related track rail and a second section bearing resiliently against a base portion of the .[.channel.]. .Iadd.casing .Iaddend.member to hold the .[.channel.]. .Iadd.casing .Iaddend.member against the adjacent rail web. 12. The apparatus of claim 10, each of said cables comprising as its said wire a single, central strand of a chromium-nickel electrical resistance alloy, as its said insulating material a plurality of layers of ceramic or silica fibers braided onto said strand, and as its said sheath a heat and oxidation resistant metal armor braided onto and about the outermost of said layers. 13. The apparatus of claim 12, said armor being braided of copper-nickel wires. 14. The apparatus of claim 12, .Iadd.wherein .Iaddend.said strand, said layers and .Iadd.said .Iaddend.armor are constructed and assembled to linearly expand at nearly the same rate. 15. The apparatus of claim 10, further comprising a trough extending between said fixed rails in the region of each of said tie rods and supporting a second portion of said cable. 16. Apparatus for heating a railroad rail switch that includes two track rails and two switch rails movable laterally to and away from the track rails on underlying switch plates, each of the track rails being supported laterally at its outer side, along a reach thereof beside a switch rail, by a series of rail braces spaced apart therealong, said apparatus comprising: an elongate, bendable, high temperature heating cable disposed along the outer side of each track rail through said reach thereof, each said cable comprising an electrical resistance heating wire encased in high temperature resistant electrically insulating material confined inside a thermally conductive deformable metal sheath, each said cable having a length thereof disposed lengthwise against the web of the related track rail along each region of such rail between adjacent rail braces, and having in the vicinity of each rail brace, between lengths of the cable so disposed, a portion of the cable which is bent upwardly and over the brace; an elongate, .[.pliable.]. heat insulating mat disposed lengthwise against and along each said length of said cable and portions of the rail web laterally adjacent thereto to prevent heat losses by convection or radiation from the cable length, each said mat comprising an elongate mass of high temperature resistant ceramic fiber insulation confined .[.in a flexible sleeve of high temperature resistant wire mesh.]. .Iadd.by means .Iaddend.that prevents fiber of said mass from creeping between the cable and said rail web; an elongate, substantially rigid, sheet metal casing member of substantially U-shaped cross-section fitted lengthwise over and enclosing each said mat, and bearing along the edges of its side walls against said rail web to confine the mat in place; means holding each said .[.channel.]. .Iadd.casing .Iaddend.member tightly in place against the related rail web; and means for supplying current at high .[.wattage to.]. .Iadd.watt density through .Iaddend.said wire of each said cable; whereby said track rails along said cable lengths and consequently said switch plates and said switch rails are heated efficiently by conduction, yet burnout of said cables is prevented, during heating of said cables by said current. 17. The apparatus of claim 16, said holding means comprising for each said .[.channel.]. .Iadd.casing .Iaddend.member a spring clip having a first section embracing the base flange of the related track rail and a second section bearing resiliently against a base portion of the .[.channel.]. .Iadd.casing .Iaddend.member to hold the .[.channel.]. .Iadd.casing .Iaddend.member against the adjacent rail web. 18. The apparatus of claim 16, each said cable comprising as its said wire a single, central strand of a chromium-nickel electrical resistance alloy, as its said insulating material a plurality of layers of ceramic or silica fibers braided onto said strand, and as its said sheath a heat and oxidation resistant metal armor bat braided onto and about the outermost of said layers. 19. The apparatus of claim 18, said armor being braided of copper-nickel wires. 20. The apparatus of claim 18, said strand, said layers and bat having substantially the same linear coefficient of thermal expansion. 21. A method of preventing obstruction of a railroad rail switch by ice or snow, said switch including a fixed main track rail, a fixed side track rail sloped away from said main rail to form a side track, and main and side switch rails movable laterally to and away from said fixed rails inside the latter on switch plates underlying said rails, said method comprising at times of freezing weather conditions flowing electrical current at high .[.wattage.]. .Iadd.watt density .Iaddend.through an electrical resistance wire inside a thermally conductive electrically insulating cable fixed along and next to the outer side of each of said fixed rails at the location of said switch rails, said cable comprising said wire encased in layers of electrically insulating ceramic fibers confined in a heat-resistant metal sheath, obstructing heat flow by radiation and convection from said cable with an elongate, .[.pliable.]. heat insulating mat disposed lengthwise against and along said cable and portions of the web of said fixed rails laterally adjacent thereto, said mat comprising an elongate mass of high temperature resistant ceramic fiber insulation confined .[.in a flexible sleeve.]. .Iadd.by means .Iaddend.that prevents said mass from creeping between said cable and said rails whereby the heat generated in said cable by the current flow passes predominantly into said fixed rails by conduction, and maintaining said switch rails at above freezing temperature by conduction of heat to them through said switch plates.

Details for Patent RE31081

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Emergent Biosolutions Canada Inc.	BAT	botulism antitoxin heptavalent (a, b, c, d, e, f, g) - (equine)	Solution	125462	03/22/2013		2040-01-29