US3126468A

US3126468A - Radiant heating panel

Info

Publication number: US3126468A
Authority: US
Publication date: 1964-03-24
Anticipated expiration: 1981-03-24

Description

March 24, 1964 D. A. AITKEN ETAL.

RADIANT HEATING PANEL 3 Sheets-Sheet 1 Filed Oct. 11, 1962 INVENTORSE Dav/d4. Airken David A. Ali/ken, Jn Ca/w'n M. Aifken BY 4 v i ATTORNEYS March 24, 1964 D. A. AITKEN ETAL 3,126,463

RADIANT HEATING PANEL Filed Oct. 11, 1962 3 Sheets-Shet 2 Call/ink Airken ATTORNEYS;

United States Patent ()fice A 3,126,468 Patented Mar. 24, 1964 3,126,468 RADIANT HEATING PANEL David A. Aitken, Euclid, David A. Aitken, Jr., South Euclid, and Calvin M. Aitken, Mayfield Heights, Ohio,

assignors to Aitken Products, Inc., Cleveland, Ohio, a

corporation of Ohio Filed Oct. 11, 1962, Ser. No. 229,803 13 Claims. (Cl. 219-34) This invention relates to radiant heating panels and more particularly to electrically energized radiant heating panels adapted for heavy industrial uses under adverse conditions.

In industrial facilities which require the use of coal or which are involved in the handling of ore or other aggregate material, the problem of thawing large carloads of this material during the winter months is very acute. The use of fuel burners to thaw the contents of railroad cars is a past practice which is both undesirable from the standpoint of expense and dangerous in that it gives rise to detrimental effects on the cars and other equipment.

The most recent development in this field provides a plurality of infra-red heating panels arranged in three banks, one on either side of a railroad track and one located between the rails such as to be situated beneath a railroad car, the contents of which is to be thawed. The entire cluster of panels and the section of track are usually housed in a shed or the like so that some heat retention is provided in the immediate area occupied by the car.

While the use of electric infra-red or radiant heating panels is inexpensive in theory and highly efiicient as to rate of heat transfer, a serious problem has arisen with respect to maintenance of the heating panels located beneath the railroad car. When the contents of the car begin the thaw, the moisture frozen therein drains into the heating panels along with fines and other foreign matter which collect around the heater elements and cause burnouts. Even quantities of material not sufficient to smother the heating elements will discolor and encrust the reflecting surfaces greatly reducing reflectivity and resulting in radiant heat loss.

In addition, the individual heating elements operating at sheath temperatures of 1550 to 1650 degrees Fahrenheit under normal exterior operating temperatures of to degrees Fahrenheit present problems of unequal component expansion and contraction which creates buckling and distortion of the heating panels.

The present invention deals with improvements in the type of radiant heating panel disclosed and claimed in our Patent No. 3,036,191 issued May 22, 1962.

It is a primary object of this invention to provide shielding means for the terminal box of a heating panel whereby the terminals and wiring connections contained in said box are protected against harmful heat radiation, the operating temperature of the heating elements imposed on the terminals and wiring connections being thereby materially reduced.

Another object of this invention is to more adequately protect the terminal box from penetration of falling water by providing a drip-shield above the cover gasket of said box.

It is a further object to provide a novel reflector structure designed to permit easy assembly and removal without disturbing the heating elements and their terminals.

Still another object of this invention is to mount the reflector elements in such manner that thermal expansion and contraction of the parts will be permitted thus avoiding harmful distortion thereof.

These and other objects of this invention will become apparent with reference to the following specification and drawings which disclose a preferred embodiment of the invention.

In the drawings:

FIGURE 1 is a perspective view of the assembled radiant heating panel;

FIGURE 2 is an exploded view in perspective showing various parts in non-assembled condition;

FIGURE 3 is an end elevational view of the device with the end plate partially broken away;

FIGURE 4 is a fragmentary sectional view taken along line 4-4 of FIGURE 3;

FIGURE 5 is a cross-sectional view taken along line 55 of FIGURE 1;

FIGURE 6 is a detailed sectional view taken along line 66 of FIGURE 3;

FIGURE 7 is a detailed sectional view similar to FIG- URE 6 relating to a modification; and

FIGURE 8 is a detailed cross-sectional view taken along line 88 of FIGURE 6.

Referring in detail to the drawings, and more particularly to FIGURES 1, 2 and 3, it will be seen that the structural frame of the heater 1 consists of a pair of longitudinal center channel members 2, a pair of longitudinal intermediate channel members 3, and a pair of longitudinal side channel members 4, all running parallel to the longest dimension of the heater, and all welded at one end to a combined baflle plate and drip shield 5. The opposite ends of channel members 2 and 3 are likewise welded to an end piece 6, while the opposite ends of the side channel members 4 are slidably secured to end plate 7 by bolts 8 and suitable lock nuts (not shown). To allow for thermal expansion and contraction, end plate 7 is provided with slots 9 formed in longitudinally extending flanges 10 thereof. Bolts 8 pass through bolt hole openings 11 in side channel members 4 and are slidable in said slots 9. A pair of oppositely sloping

angle bars

12 and 13 are welded to the inner vertical wall of combined baffle plate and drip shield 5 and a second set of similarly arranged angle bars are welded to the inner wall of end plate 7.

The top of the frame is open to expose a plurality of coplanar horizontally arranged U-shaped rods 14 or the like which comprise the electric heating elements of the device, said rods 14 being supported by a plurality of laterally arranged elements 15, the latter in turn being mounted at their ends in vertically disposed slots 16 in side channel members 4 and being loosely fastened therein. The upper edges of supporting elements 15 are provided with a plurality of notches 17 to accommodate the U-shaped rods 14, said slots 16 and notches 17 allowing for thermal expansion and contraction of the parts. The free ends of rods 14- extend through appropriate openings 18 in the combined baffle plate and drip shield 5. As shown in FIGURES 2 and 5, a spacer strip or plate 19 is provided with similar openings 20 permitting the free ends of rods 14 to pass through like openings in the inner wall of terminal box 21, said rods 14 terminating in conventional wire connections housed in the terminal box 21 and being secured therein by means of appropriate threaded bushings 21a, washers and nuts. To reduce strain on the terminal connections, each rod 14 is provided with a stop member 22 which engages the inner wall of baflie plate 5. If desired, greater support for the terminal box 21 may be provided by employing a plurality of bolts 23, spacer washers 24 and nuts 25. A lead to an appropriate electrical power source is shown at 25a in FIGURE 2. Terminal box 21 is equipped with a removable closure plate or cover 26 provided with a rectan gular gasket 27 secured between the closure plate 26 and vertically disposed flange portions 28 of terminal box 21 by means of cap screws 29 which terminate in and do not pass through bearing plates 30, the inner walls of said bearing plates 39 engaging and being fixed to vertically disposed outer wall portions 31 of the terminal box 21.

Again referring to FIGURE 5, it will be noted that combined baflle plate and drip shield consists of an integral generally Z-shaped member having a vertically extending end wall first portion 33 and a horizontal roof or second portion 34, the roof portion 34 terminating in a downwardly sloping lip portion 35. Foot portion 32 extends laterally inwardly from the lower edge of end wall first portion 33.

Referring particularly to FIGURES 1, 2, 3, 6 and 8, it will be seen that the reflector is divided into a pair of like plates 36 provided with integral longitudinal inner flanges 37 and integral longitudinal outer flanges 38. Each plate 36-is provided with a series of slots 39 to accommodate bolts 40. Loosely secured to each of said plates 36 and co-extensive therewith is an inverted U- shaped hold-down element 41. Said hold-down elements 41 are designed to be positioned over and slidably supported by intermediate longitudinal channels 3. Note, as shown at 42 in FIGURE 8 that there is appreciable space between the outer and inner vertically disposed wall portions of channels 3 and hold-down elements 41 respectively. Through bolts 43, with appropriate lock nuts 44, are inserted through hold-down elements 41 to maintain loose engagement of hold-down elements 41 with the intermediate longitudinal channels 3. Numeral 45, see FIGURE 2, designates a pair of hold-down angle members each of said members consisting of a vertical leg 46 and a horizontal downwardly sloping leg 47, vertical legs 46 being provided with a series of bolt-receiving openings 48; the purpose and function of hold-down angle members 45 being later described.

Referring to FIGURE 7 a modified arrangement of reflector hold-down member is disclosed. Instead of utilizing a single elongated hold-down element 41 for loosely connecting reflector plate 36 to intermediate longitudinal channel 3, the structure may be modified to provide a plurality of inverted U-shaped clips 49. Suitable bolts and lock nuts 50 secure the U-shaped clips 49 to the reflector plate 36, and in this modified form of the invention slots 39 used in the preferred embodiment are not required. Clips 49 are maintained in loose engagement with intermediate channel members 3 by means of through bolts 51 and lock nuts 52 in a fashion similar to that already described with reference to the preferred embodiment, appreciable spacing being again provided between said clips 49 and said channel members 3 to allow for expansion and contraction.

In assembling the radiant heating panel of this invention, the

channel members

2, 3 and 4 are all welded at one end to combined baflle plate and drip shield 5 said channel members 2 and 3 being likewise welded at their other ends to end piece 6,

angle bars

12 and 13 having already been welded to said baffle plate 5. The heating elements 14 are then installed being supported by the laterally disposed elements 15 mounted in side channel members 4, said heating elements 14 passing through baflie plate 5 and spacer plate 19 and being suitably secured in terminal box 21, the latter being rigidly supported by baflle plate 5, but in spaced relation thereto by virtue of the interposition of spacer plate 19. Additional support for the terminal box may be provided by bolts 23. As described up to this point, the assembly of the six longitudinal channel members, the baffle plate and the terminal box, with heater elements and heater element supports installed, should be visualized as a solid, permanent entity. In general this assembly will remain as described for the life of the heater, except that a burned out heating element may be changed occasionally.

The remaining parts now to be assembled are characterized by the fact that they may be readily installed and removed and their manner of assembly and connection with the rigidly assembled frame work allows for differences in thermal expansion and contraction. The reflector plates 36 are mounted on the frame by sliding them under the heating elements 14 and their supports 15 and positioning the inner flanges 37 between the vertical legs of channel members 2 with the hold-down elements 41 loosely engaging channel members 3, the ends of the reflector plates 36 adjacent bafile plate 5 being received beneath and held down by

angle bars

12 and 13. Holddown angle members 45 are then inserted between and above the center mating line of the reflector plates 36,

and pinned in place by means of bolts 53 which pass through the vertical legs of channel members 2 and the vertical legs 46 of angle member 45, it being noted however that bolts 53 do not pass through inner flanges 37 of reflector plates 36. Next the end plate 7, having welded to its inner wall a like pair of oppositely sloping hold-down angle bars 12 and 13, is solidly bolted to end piece 6 and slidably bolted to side channel members 4 by means of slotted flanges 10, the ends of reflector plates 35 adjacent end plate 7 being slidably received beneath said hold-down angle bars 12 and 13.

With the assembly completed it can be seen that the reflector plates 36 are free to expand uniformly or nonuniformly in all directions and yet are confined by holddown angle members 45 at the center, hold-down angle bars 12 and 13 at the ends, and hold down elements 41, or hold-down clips 49 in the modified form of FIGURE 7, loosely engaging intermediate longitudinal channel members 3. Expansion and contraction of the various

longitudinal channel members

2, 3 and 4 is permitted by the slots 9 in the flange members 10 of end plate 7.

Of particular importance is the combined baflle plate and drip shield 5 provided with the spacer plate 19 be tween said plate 5 and terminal box 21. By use of bafile plate 5 and spacer plate 19, the terminal box 21 is shielded from harmful heat radiation prolonging the useful life of the terminals and wire connections resulting in great savings and rendering frequent replacement of said parts unnecessary.

It will be further noted that roof portion 34 and lip portion 35 of baflle plate 5 extend over the top wall and closure plate 26 of the terminal box 21 whereby said box and its contents are protected against falling debris and water damage.

It will also be appreciated that the reflector plates 36 are so mounted that they may be readily removed and replaced if damaged or discolored. Further, the sloping design of the reflector plates 36 when in assembled posi tion and their outer flanges 38 provide means whereby spillage from overhead may be properly drained away.

In the preferred design, all parts are made of aluminum with the exception of the heater element supporting members which are made of stainless steel.

It is to be understood that the embodiments shown and described herein are for the purpose of example only and are not intended to limit the scope of the appended claims.

What is claimed is:

l. Radiant heating panel means for thawing ice or the like from superimposed objects, comprising an open-topped horizontal rectangular frame including a pair of longitudinal side walls and a vertical end wall having a vertical first portion;

a plurality of generally coplanar horizontally-arranged vertically upwardly exposed electrical heating elements supported in said frame;

means supplying electrical energy to said heating elements including a completely enclosed terminal box having a vertical side wall adjacent and spaced from the external surface of said end wall first portion, and conductor means in said terminal box;

spacer means intermediate said end wall and said terminal box side wall, said spacer means extending horizontally along said terminal box vertical side wall and being arranged substantially coplanar with said heating elements;

and means rigidly connecting said terminal box with said end wall, each of said heating elements including at least one terminal portion extending into said terminal box through aligned openings in said vertical first wall portion, said spacer means and said terminal box side wall for connection with said conductor means, the end wall of said frame including at its upper edge a horizontal second portion extending completely across said terminal box, and a downwardly inclined lip portion connected with the free edge of said second portion, whereby the end wall of said frame constitutes a baflle plate and drip shield for protecting said terminal box against radiant heat and falling particles and liquids.

2. A radiant heating panel comprising a horizontally-arranged rectangular frame including a generally vertical end wall, a pair of parallel longitudinal side channel members, a pair of longitudinal center channel members intermediate and parallel with said side channel members, a pair of longitudinal intermediate channel members each of which is arranged between, parallel with and spaced from one of said longitudinal center channel members and the adjacent longitudinal side channel member, each of said channel members being rigidly secured at one end to said end wall, a vertical end piece rigidly secured to the free ends of said pairs of center and intermediate channel members, an end plate adjacent the free ends of said side channel members and on the opposite side of said end piece from said end wall, and means slidably connecting said end plate with the free ends of said side channel members to permit movement of said end plate longitudinally of said frame;

a plurality of horizontal coplanar electrical heating elements mounted in said frame above said center and said intermediate channel members;

and longitudinally extending reflector means supported on said center and said intermediate channel members below said heating elements.

3. Apparatus as defined in claim 2 wherein said means slidably connecting said end plate with said side channel members comprises a pair of vertical flange portions on said end plate extending adjacent and parallel with the free end portions of said side channel members, one of said portions including longitudinally extending slots and the adjacent cooperating portion including bolt means extending through said slots for slidably connecting said flange portions with said side channel members.

4. Apparatus as defined in claim 3 wherein said reflector means includes a pair of longitudinally extending reflector plates on opposite sides of the longitudinal center line of said firame, each of said reflector plates being supported by one of said center channel members and the associated intermediate channel member.

5. Apparatus as defined in claim 4 wherein each of said reflector plates is slightly inclined about its longitudinal axis relative to the horizontal, the longitudinal edge of said reflector plate adjacent the center channel member being at a higher elevation than the other longitudinal edge.

6. Apparatus as defined in claim 5 wherein said reflector plates have at one end transverse edge portions that extend above said end piece and terminate adjacent said end plate, said reflector plates having at the other end transverse edge portions that terminate adjacent said end wall; and further including hold down means controlling the vertical movement of said reflector plates relative to said frame, said hold down means comprising hold downbar-s secured to the adjacent surfaces of said end wall and said end plate, said hold down bars being arranged for contiguous coextensive engagement with the upper surfaces of the transverse edge portions at each end of each of aid reflector plates.

7. Apparatus as defined in claim 6, wherein said hold down means further include auxiliary means loosely connecting said reflector plates with said intermediate channel members to permit free longitudinal movement and limited vertical and transverse movement of said reflector plates relative to said intermediate channel members.

8. Apparatus as defined in claim 7 wherein said auxiliary hold down means comprises longitudinally arranged inverted U-shaped channel elements connected with the lower surfaces of said reflector plates and receiving said intermediate channel members, and transverse pin means extending between the flanges of said U-shaped channel elements below and spaced from said intermediate channel members.

9. Apparatus as defined in claim 8 wherein the auxiliary hold down means associated with each of said reflector plates comprises a single continuous U-shaped channel element, and pin and slot means connecting said U-shaped channel element with said reflector plate to permit relative longitudinal movement therebetween.

10. Apparatus as defined in claim 8 wherein the auxiliary hold down means associated with each of said reflector plates comprises a plurality of aligned, longitudinally spaced U-shaped channel elements.

11. Apparatus as defined in claim 8, wherein each of said reflector plates includes a longitudinal downwardly extending flange portion extending between said center channel members, and further wherein said hold down means includes a generally T-shaped hold down member having upper flange portions extending above and in contiguous coextensive engagement with the adjacent upper longitudinal surfaces of said reflector plates, said T- shaped hold down member having a vertical portion extending downwardly between and beyond the adjacent flange portions of said reflector plates, and pin means connecting the lower end of the vertical portion of said T-shaped hold down member that extends below said reflector flanges with said center channel members.

12. Apparatus as defined in claim 11 wherein said T- shaped member consists of a pair of angle arms having abutting legs.

13. Apparatus as defined in claim 8 wherein the end wall of said frame includes a vertical first portion; and further including means supplying electrical energy to said heating element comprising a terminal box having a vertical side wall adjacent and spaced from the external surface of said end wall first portion, and conductor means in said terminal box; spacer means intermediate said end wall and said terminal box side wall; and means rigidly connecting said terminal box with said end wall and said spacer means, each of said heating elements including at least one terminal portion extending into said terminal box through aligned openings in said vertical first wall portion, said spacer means and said terminal box side wall for connection with said conductor means, the end wall of said frame including a horizontal second portion connected with the upper edge of said first portion and extending substantially completely across said terminal box.

References Cited in the file of this patent UNITED STATES PATENTS 1,892,298 Bray Dec. 28, 1932 2,259,143 Shroyer Oct. 14, 1941 2,843,716 Del Francia July 15, 1958 2,877,332 Senior Mar. 10, 1959 FOREIGN PATENTS 321,065 Great Britain Oct. 31, 1929 119,936 Australia May 7, 1945

Claims

1. RADIANT HEATING PANEL MEANS FOR THAWING ICE OR THE LIKE FROM SUPERIMPOSED OBJECTS, COMPRISING AN OPEN-TOPPED HORIZONTAL RECTANGULAR FRAME INCLUDING A PAIR OF LONGITUDINAL SIDE WALLS AND A VERTICAL END WALL HAVING A VERTICAL FIRST PORTION; A PLURALITY OF GENERALLY COPLANAR HORIZONTALLY-ARRANGED VERTICALLY UPWARDLY EXPOSED ELECTRICAL HEATING ELEMENTS SUPPORTED IN SAID FRAME; MEANS SUPPLYING ELECTRICAL ENERGY TO SAID HEATING ELEMENTS INCLUDING A COMPLETELY ENCLOSED TERMINAL BOX HAVING A VERTICAL SIDE WALL ADJACENT AND SPACED FROM THE EXTERNAL SURFACE OF SAID END WALL FIRST PORTION, AND CONDUCTOR MEANS IN SAID TERMINAL BOX; SPACER MEANS INTERMEDIATE SAID END WALL AND SAID TERMINAL BOX SIDE WALL, SAID SPACER MEANS EXTENDING HORIZONTALLY ALONG SAID TERMINAL BOX VERTICAL SIDE WALL AND BEING ARRANGED SUBSTANTIALLY COPLANAR WITH SAID HEATING ELEMENTS; AND MEANS RIGIDLY CONNECTING SAID TERMINAL BOX WITH SAID END WALL, EACH OF SAID HEATING ELEMENTS INCLUDING AT LEAST ONE TERMINAL PORTION EXTENDING INTO SAID TERMINAL BOX THROUGH ALIGNED OPENINGS IN SAID VERTICAL FIRST WALL PORTION, SAID SPACER MEANS AND SAID TERMINAL BOX SIDE WALL FOR CONNECTION WITH SAID CONDUCTOR MEANS, THE END WALL OF SAID FRAME INCLUDING AT ITS UPPER EDGE A HORIZONTAL SECOND PORTION EXTENDING COMPLETELY ACROSS SAID TERMINAL BOX, AND A DOWNWARDLY INCLINED LIP PORTION CONNECTED WITH THE FREE EDGE OF SAID SECOND PORTION, WHEREBY THE END WALL OF SAID FRAME CONSTITUTES A BAFFLE PLATE AND DRIP SHIELD FOR PROTECTING SAID TERMINAL BOX AGAINST RADIANT HEAT AND FALLING PARTICLES AND LIQUIDS.