US3749881A

US3749881A - Electric heater assembly

Info

Publication number: US3749881A
Application number: US00203998A
Authority: US
Inventors: Y Tanaka
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-12-02
Filing date: 1971-12-02
Publication date: 1973-07-31
Anticipated expiration: 1990-07-31

Abstract

A flexible radiant heater assembly for radiantly heating a structure having a curved surface comprises a plurality of longitudinally flexible ribbon heaters juxtaposed in spaced parallel relationship. An upright piece extending upwardly at right angles to the plane of the ribbon heater is provided at each end of each heater. The heaters are electrically connected together in series by conductor wires joining the upright preces of adjacent heaters. A plurality of heat-proofing and insulating holder members extend transversely of said heaters at spaced points in the longitudinal direction thereof with each of the holder members being secured to a major face of each of the heaters. The major surface of each heater has an adiabatic fabric mounted thereon and the holder members hold the heater and fabric together by compression. The outermost ones of the holder members are secured to the upright pieces at the ends of the heaters. Legs secured at the opposite ends of each of the holder members depend vertically therefrom and extend beyond the other major surface of each of the heaters so as to hold the heaters in spaced relationship from the surface to be heated.

Description

United States Patent 11 1 I Tanaka 1 1 ELECTRTC HEATER ASSEMBLY [76] inventor: Yukio Tanaka, 16-19 Shimouma 4-chome, Setagaya-ku, Tokyo,

Japan Y [22] Filed: Dec. 2, 1971 [21] Appl. No.: 203,998

219/531, 219/535', 21'9/549, 338/210, 338/319 51 1m.c1....' 1105b 3/02 58 Field ofSearch ..219/339, 342, 350-358,

Hess I: 2191550 1 July 31, 1973 Primary ExaminerAnthony Bartis Attorney-Nelson Littell et al.

[5 7 1 ABSTRACT A flexible radiant heater assembly for radiantly heating a structure having a curved surface comprises a plurality of longitudinally flexible ribbon heaters juxtaposed in spaced parallel relationship. An upright piece extending upwardly at right angles to theplane of the rib H bon heater is provided'at each end of each heater. The

heaters are electrically connected together in series by conductor wires joining the upright preces of adjacent I heaters. A plurality of heat-proofing and insulating holder members extend transversely of said heaters at spaced points in the longitudinal direction thereof with each of the holder members being secured to'a major face of each of the heaters. The major surface of each heater has an adiabatic fabric mounted thereon and the holder members hold the heater and fabric together by compression. The outermost ones of the holder members are secured to the upright pieces at the ends of the heaters. Legs secured at the opposite ends of each of the holder members depend vertically therefrom and extend beyond the other major surface of each of the heaters so as to hold the heaters in spaced relationship from the surface to be heated.

2 Claims, 5 Drawing Figures 1 ELECTRIC HEATER ASSEMBLY BACKGROUND OF THE INVENTION This invention relates to a radiant electric heater assembly suitably employed for radiantly heating a structure having a curved surface such as a ship hull, tubular body or the like. l

Large structures having curved surfaces employed in a various industrial fields are required to be heated. For example, in the ship building industry, welded joints on ship hulls are required to be heattreated. According FIG. 2 is a cross-sectional view taken substantially along the line'2 2 of FIG. 1 and showing one heater and its associated parts of the assembly;

FIG. 3 is a cross-sectional view taken substantially along the line 3 3 of FIG. 1 and showing another portion of the heater and its associated parts of FIG. 2;

FIG. 4 is a view of an arrangement of a plurality of heater assemblies each corresponding to that as shown to one of the conventional methodsfor heat-treating";

SUMMARY OF THE INVENTION I Therefore, one object of the present invention is to provide a radiantelectric heater assembly and apparatus which facilitates preparation for heating operation for a structure having a curved surface.

Another object of the present invention is to provide a heater assembly and apparatus of the above. type which can be vers'atilely appliedtostructures having varying sizes and curvatures to be heated.

in FIG. I which arrangement is for heating a structure having a large curved surface; and A FIG. 5 is a view showing mechanical-and electrical connections between adjacent heaterassemblies in said g arrangement of FIG. 4. I

PREFERRED EMBODIMENT OF THE INVENTION The present invention will be now described referring to theaccompanying drawing and more particularly, to FIG. 1 thereof. In FIG. 1, one preferred embodiment of the heater assembly of the invention is generally shown by reference numeral 1 and the heater assembly generally comprises a plurality of longitudinally flexible ribbon heaters 2 which are juxtaposed in such aspaced relationship that the axes of these heaters extend parallel to each other. Each 'of these heaters2 comprises a conventional electric heating strip which is essentially flexural or flexible in the longitudinal direction and therefore, the strip is required to have a relatively small thickness such as 1 mm, for example. The heater or strip 2 has at the opposite ends integral upright pieces 2a fonned by upwardly bending the strip'2 atthe oppo 5 site ends at rightfangles to oneof the major surfaces of the strip 2. The adjacent ribbon heaters 2 are electri According to the present invention, there has been provided an electric heater assembly for. radiantly heating a structure having a curved surface comprising a plurality of longitudinally flexible ribbon heaters juxtaposed in parallel and spaced relationship; means for electrically connecting said heaters; an electric power supply for supplying electric power to said heaters; heat-proofing and insulating holder members extending transversely of said heaters at spaced points in the longitudinal direction of each of the heaters on one major surface of each of the heaters, each of said holder members beingsecured to one major surface of each of the heaters; legs secured to said holder members depending vertically therefrom and extending beyond the other major surface of each of the heaters for'holding the heaters in spaced relationship from the surface of the structureto be heated. l

The above and other objects and attendant advanrages of the present, invention will be more readily apparent to those skilled in the art from areading of the followingdetailed description of the invention in conjunction with the'accompanying drawing inwhich one preferredembodiment of the invention is shown for illustration purpose only, but not for limiting the scope of the same in anyway.

BRIEF DESCRIPTIONOF THE DRAWING FIG. 1 is a perspective view of one preferred embodiment of radiant electric heater assembly constructed in Y accordance with the present invention with portions thereof broken away; I

cally connected at alternate one end upright piece'2a" of each heater by means of a conductor wire 3. The other end upright pieces 2a of the outermost ribbon heaters 2 are provided with conductor wires 4 which are adapted to connect these outermost ribbon heaters to the corresponding ribbon heaters of adjacent heater holder members 6 which are preferably formed of the heat-resisting and thermally andelectrically insulating material sold under the trade name Hemmit Rod extend transversely of the juxtaposed ribbon heaters 2 at spaced points in the longitudinal direction of each of the heaters and pressed against the fabrics 5 under pressure sufficient to compress thefabrics 5 down. The

holder members 6 are secured to the he'aters2 by wires 7 in the manner whichpwill be described hereinbelow.

That is, each of the wires 7 associated with'the outer most holder members 6 extends along the inner side of the associated holder member and then through transverse through holes 6a in the holder member to project out of the outer side of the holder member andthe ex-' I along the underside of the associated heater 2 and then through vertical holes 6b in the associated holder member to project out of the upper side of the holder member and the exposed opposite ends of the wire 7 are may be employed inassociation with the outermost holder members 6 in the same manner as mentioned in connection with the wires associated with the rest of the holder members referred to hereinabove. It will be understood thatsince the holder members 6 are disposed at longitudinally spaced points of each heater 2 and hold the same together, the heaters are assembled in such a manner that they are allowed to flex in the longitudinal direction. The opposite ends of each of the holder members 6 are shown as extending beyond the outer edges of the outermost heaters 2.

In order to keep the ribbon heaters 2 spaced in a predetermined relationship from a curved surface of a structure to be heated, depending legs 8 are connected to the opposite ends of each of the holder members 6 in a conventional manner and the legs depend verti' cally and downwardly from the upper surface of the respectively associated holder members and extend beyond the undersurfaces of the heaters-2. The legs 8 may be formed of a metal such as aluminum or any other suitable heat-resisting and insulating material.

' Turning now to FIG. 4, there'is shown an arrangement comprising a plurality of ribbon heater assemblies juxtaposed and electrically connected each corresponding to that shown in FIG. 1 and the arrangement is suitable employed for-heating a structure having'a relatively large size. However, it will be easily appreciated that if the structure is of a relatively small size, only one heater assembly is sufficient to heat such a structure. In FIG. 4, the structure to the heated is shown by reference numberal 9 and the heater assemblies l are disposed along the-curved outer periphery of the structure with the axes of the ribbon heaters 2 in adjacent assemblies in alignment with each other and held in position by any suitable conventional means. As described hereinabove, with each heater assembly, since the holder members 6 are spaced in the longitudinal direction of the respectively associated ribbon heaters 2, the heaters and accordingly, the entire heater assembly is allowed to flex in the longitudinal direction of its heaters 2. Therefore, the heater assemblies can easily follow the curved contour surface of the structure. As shown in FIG. 5, adjacent heater assemblies are conveniently connected to each other by means of connection means 10. The connection ,means lis shown as comprising an arm 11 extending between the legs 8 of the outermost holder members 6 in the adjacent heater assemblies and screws 12 which secure the arm to the adjacent legs 8. For the purpose, as shown in FIG. 1, the legs 8 associated with the outer- 4 associated with the outermost holder members 6 of the outermost heater assembles l in the arrangement as shown in FIG. 4 are connected to a power supply (not shown) To supply electric power to the heaters. Alternatively, the heater assemblies can be in parallel connected to the power supply. Otherwise, the heater as semblies may be conveniently connected to a three phase power supply in a conventional manner. If an arrangement comprises 'a great number of heat assemblies, the assemblies may be grouped into aplurality of groups and the assemblies in each group may be inseries connected to each other and the groups may be in parallelconnected to each other". When electric power is allowed to flow through the heater assemblies in such a multi-arrangement, the heater assemblies can radiantly heat a curved surface of a structure to perform a desired treatment on the structure.

In order to prevent the holder members from displacing due to vibrative force which will develop when electric power is supplied to the heater assembly or assemblies, the adjacent holder members can be additionally maintained in a desired or predetermined spaced relationship by means of metal wires or the like.

While there has been described what is at present,

considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is aimed, therefore, in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the'invention. What is claimed is:

l. A heater assembly for radiantly heating a structure having a curved surface, which comprises a plurality of longitudinal-1y flexible ribbon heaters juxtaposed inparallel and spaced relationship; means for electrically connecting said ribbon heaters comprising an'upright piece extending upwardly at rightangles 'to the plane of the heater and a conductor wire connecting said upright pieces at the corresponding one end of'adjacent heaters; an electric power supply for supplying electric power to said heaters; a plurality of heat-proofing and insulating holder members extending transversely of said heaters at spaced points in the longitudinal direction of each of the heaters, each of said holder members being secured to one major surface of each of the heaters; said major surface of each of the ribbon heatmost holder members 6 are preferably provided with v threaded holes for receiving the screws 12. The conductor wires 4 of adjacent heater assemblies 1 are electrically connected to each other in any conventional suitable manner as shown at 13. The conductor wires ers having an adiabatic fabric mounted thereon and' said holder members holding the heaters and theirfabrics together so as to compress the fabrics down; the

outermost ones of said holder members being secured to said upright pieces of the heaters; and legs secured to said holder members at the opposite ends of each of the holder members depending vertically therefrom and extending beyond the'other major surface of each of the heaters so as to hold the heatersin spaced relaj tionship from the surface of said structure.

2. An apparatus for radiantly heating a structure member having a curved surface which comprises a plurality of heater assemblies juxtaposed, and each 1 heater assembly comprises a plurality of longitudinally extending beyond theiother'major surface of each of the heaters so as to hold the heaters in spaced relationship from the surface of said structure; means for mechanically connecting the legs associated with the outermost holder members of adjacent heater assemblies and said ribbon heaters of each assembly being electrically connected to an electric power supply for supplying electric power to the heaters. l

Claims

1. A heater assembly for radiantly heating a structure having a curved surface, which comprises a plurality of longitudinally flexible ribbon heaters juxtaposed in parallel and spaced relationship; means for electrically connecting said ribbon heaters comprising an upright piece extending upwardly at right angles to the plane of the heater and a conductor wire connecting said upright pieces at the corresponding one end of adjacent heaters; an electric power supply for supplying electric power to said heaters; a plurality of heat-proofing and insulating holder members extending transversely of said heaters at spaced points in the longitudinal direction of each of the heaters, each of said holder members being secured to one major surface of each of the heaters; said major surface of each of the ribbon heaters having an adiabatic fabric mounted thereon and said holder members holding the heaters and their fabrics together so as to compress the fabrics down; the outermost ones of said holder members being secured to said upright pieces of the heaters; and legs secured to said holder members at the opposite ends of each of the holder members depending vertically therefrom and extending beyond the other major surface of each of the heaters so as to hold the heaters in spaced relationship from the surface of said structure.

2. An apparatus for radiantly heating a structure member having a curved surface which comprises a plurality of heater assemblies juxtaposed, and each heater assembly comprises a plurality of longitudinally flexible ribbon heaters juxtaposed in parallel and spaced relationship; means for electrically connecting said heaters comprising an upright piece formed by upwardly bending each of the heaters at the opposite ends of the associated heater at right angles to the plane of the heater and a conductor wire connecting said upright pieces at the corresponding one end of adjacent heaters; a plurality of heat-proofing and insulating holder members extending transversely of said heaters at spaced points in the longitudinal direction of each of the heaters, each of said holder members being secured to one major surface of each of the heaters and the outermost ones of said holder members being secured to said uprIght pieces of the heaters; and legs secured to said holder members at the opposite ends of each of the holder members depending vertically therefrom and extending beyond the other major surface of each of the heaters so as to hold the heaters in spaced relationship from the surface of said structure; means for mechanically connecting the legs associated with the outermost holder members of adjacent heater assemblies and said ribbon heaters of each assembly being electrically connected to an electric power supply for supplying electric power to the heaters.