US3124120A

US3124120A - Warm floor space heater

Info

Publication number: US3124120A
Authority: US
Publication date: 1964-03-10
Anticipated expiration: 1981-03-10

Description

March 10, 1964 w, BEST WARM FLOOR SPACE HEATER S Sheets-Sheet 1 Filed Nov. 24, 1959 M E; Q m .IIH MM IHIIIMH W iw WW JNVENTOR.

' BY (W 8% March 10, 1964 w. H. BEST WARM FLOOR SPACE HEATER 3 Sheets-Sheet 2 Filed NOV. 24, 1959 W/Wie H. Best INVENTOR.

BY an Wavy 15m United States Patent f 3,124,120 WARM FLOOR PAE HEATER Willie H. Best, Coiumhia, S.C., assignor, by mesne assignments, to Southern Industries, Inc., Richmond, Va., a corporation of Virginia Fiied Nov. 24, 1959, Ser. No. 855,226 1 Claim. (iii. 126-410) The present invention generally relates to a heating device and more particularly to a space heater incorporating novel structural features and arrangements for increasing the over-all efiiciency of the device and to discharge hot air towards the floor of the space or room being heated for more even distribution of the heated air.

The primary object of the present invention is to provide a space heater incorporating in its construction a substantially L-shaped heat exchanger including a primary heat exchanger and a secondary heat exchanger together with a blower for forcing air peripherally over substantially the complete external surface of the heat exchanger thereby more effectively cooling the exhaust products and heating the cool air while also maintaining an enclosing cabinet in cool condition so that the top of the cabinet or casing for the space heater may be employed for other purposes such as a table top since the temperature thereof is only slightly above the ambient temperature.

Another object of the present invention is to provide a space heater in which the air being heated is discharged from one end and a portion of one side of the casing or cabinet with such air also moving downwardly when being discharged whereby the heated air will effectively warm the floor area of the room or space being heated and will not rapidly move towards the ceiling as would Occur if the heated air were discharged while moving vertically upwardly.

Yet another object of the present invention is to provide a space heater of the character described in which the secondary heat exchanger is provided with a battle whereby the exhaust products will travel down one side of the baffle, around the end thereof and back on the other side of the baffle for discharge through a chimney or the like thereby increasing the effective area of the heat exchanger and also providing better heat exchange between the heated exhaust products and the secondary heat exchanger by the surface friction between the moving air and the inner surface of the heat exchanger.

Still another important object of the present invention is to provide a space heater in accordance with the preceding objects in which the space heater is provided with a novel burner arrangement in which the combustion supporting air is discharged into a jacket or plenum chamber encircling the burner with the air then passing under a bafile before entering the burner whereby the pressure forced draft for supporting combustion will be evenly distributed completely around the burner.

Another very important feature of the present invention is to provide a space heater which is quite compact in construction, arranged so that the components efliciently employ the space within the cabinet, efficient in operation, easy to install, safe in operation and generally inexpensive to manufacture.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and arrangement as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of the space heater of the present invention illustrating the cabinet or casing and the discharge area therein for discharge of heated an;

3,124,120 Patented Mar. 10, I964 FIGURE 2 is an end elevational view of the structure of FIGURE 1 illustrating the discharge end of the space heater;

FIGURE 3 is an end elevational view of the construction of FIGURE 1 illustrating the air intake for the air circulating fan;

FIGURE 4 is a longitudinal, vertical sectional view taken substantially upon a plane passing along section line 44 of FIGURE 2 and illustrating further structural details of the interior of the space heater;

FIGURE 5 is a transverse, plan sectional view taken substantially upon a plane passing along section line '55 of FIGURE 4 illustrating the construction of the secondary heat exchanger and the relationship thereof to the primary heat exchanger;

FIGURE 6 is a vertical sectional view taken substantially upon a plane passing along section line 66 of FIGURE 4 illustrating further structural details of the heat exchanger and other features of the space heater; and

FIGURE 7 is a perspective view, with portions broken away, of the heat exchanger illustrating the construction of the primary and secondary heat exchangers and the battle 'in the secondary heat exchanger.

Referring now specifically to the drawings, the numeral It generally designates the space heater of the present invention which includes a generally rectangular cabinet or casing generally designated by the numeral 12 which includes a top 14, a front wall 16,

end walls

18 and 20 and a rear wall 22. The bottom of the cabinet 12 is closed by a bottom wall 24- which may rest directly on the floor surface or be provided with any suitable type of supporting mechanism. The various components of the cabinet 12 may be detached from each other and the front wall 16 is provided with an enlarged opening 26 adjacentone end thereof that is closed with a wire mesh or foraminous member 28 that is provided with a peripheral frame 30. The end wall 20 is provided with a similar enlarged opening having a wire mesh closure 32 mounted on a peripheral frame member 34. The openings in the front and end walls extend substantially throughout the vertical height thereof and provide enlarged discharge openings for heated air whereby the disr charge openings arranged in perpendicular relation to each other will discharge the air in perpendicular lateral directions for distributing the air more evenly around the space being heated. Also, the air is discharged from the discharge openings in a downward direction thereby causing the air to be discharged towards the floor surface for warming the floor surface and otherwise distributing the heat more evenly throughout the room area being heated with a minimum amount of stratification of the air within the room.

Disposed within the cabinet 12 is a substantially L- shaped heat exchanger generally designated by the numeral 35 and including a vertically disposed primary heat exchanger assembly 33 and a horizontally disposed secondary heat exchanger 4d. The vertical primary heat exchanger 38 is disposed within the cabinet 12 adjacent the discharge end of the cabinet while the horizontal secondary heat exchanger 40' extends toward the end wall 18. The interior of the primary heat exchanger 38 is hollow and unobstructed with the interior of the secondary heat exchanger at; having a vertical baflie 42 therein having one end edge spaced from the corresponding end wall 44 of the secondary heat exchanger 40. The other end of the bafiie 42 is connected to an extension plate 46 which forms an extension of one wall of the primary heat exchanger 38 and the bafiie 42 as well as the extension 46 extends to the top 48 of the heat exchanger whereby the hot combustion products passing upwardly in the primary heat exchanger must necessarily pass alongside of one surface of the baffle 42 towards the end wall 44 and then around the baflle 42 and back up the other sides thereof for discharge through a discharge opening 50 in the side wall of the heat exchanger which is adjacent to the extension plate 46 and disposed in the horizontal secondary heat exchanger 40.

Connected with the secondary heat exchanger 40 is an exhaust pipe or flue pipe 52 which extends through the rear wall 22 and is connected to the heat exchanger with the opening 54) being aligned with the interior of the flue pipe 52 for discharge of hot combustion products. The wall 54 of the primary heat exchanger 38 which is disposed remotely from the secondary heat exchanger 40 is provided with an enlarged opening 56 adjacent the bottom thereof which is normally closed by a closure door 58 which permits access to a burner generally designated by the numeral 60 which is set in the bottom of the heat exchanger 36. Thus, the inspection door 58 permits access to the interior of the heat exchanger for cleaning purposes and also for access to the burner. By removing the wire mesh screen 32 and the frame 34 by removing the bolts or other fastening devices holding the frame 34 in position, the access door 58 may be readily opened by virtue of the hinge supporting mechanism 62 and a knob 64 for locking and unlocking the inspection door 58.

Disposed above the bottom of the primary heat exchanger 38, there is provided an inwardly extending flange 66 vertically spaced from the bottom wall 63 of the primary heat exchanger 38 and the flange 66 is provided with an enlarged opening 70 for receiving a cylindrical burner assembly 72 having a peripheral flange 74 resting on the flange 66. The cylindrical burner assembly 72 is provided with a plurality of openings 76 for supplying combustion supporting air. Disposed between the burner assembly '72 and the interior of the primary heat exchanger 38 is a baffle 78 integral with the flange 66 and having the lower edge terminating above the bottom 63. The bafiie 78 is concentric with the burner assembly 72 but spaced therefrom. The bottom of the burner assembly 72 is provided with a fuel supply conduit 80 that extends from a suitable fuel valve or carburetor 82 which may be connected to the fuel pump or tank in any suitable manner for supplying fuel to the burner assembly 72. For supplying air, there is provided a blower 84 connected to a discharge pipe 86 therefor which extends to and connects with the primary heat exchanger 33 and actually is connected to the opening 88 formed therein whereby air discharged by the draft air blower 84 will be discharged into the area between the bafile 78 and the lower wall 68 and between the baffle 78 and the peripheral wall of the primary heat exchanger 38 so that the pressure of forced air draft will be substantially equalized throughout the periphery of the burner thereby increasing the effectiveness of the burner.

The heat exchanger 36 is isolated by virtue of a vertical partition wall 89 that extends upwardly from the bottom wall 24 and between the front and rear walls and in spaced relation to the vertical wall of the primary heat exchanger 38 having the opening 88 therein. Connected to the upper end of the partition 89 is a horizontal partition 90 having an enlarged opening 92 therein.

Brackets

94 and 96 evenly maintain the heat exchanger in proper orientation. The primary heat exchanger is supported by a transverse support member 98 and angle iron brackets 1W.

Disposed within the compartment formed by the partition walls 89 and 9% there is provided a fan 99 having a discharge adapter 101 on the housing therefor connected to the opening 92 for discharging air into the interior of the cabinet and thus outwardly through the discharge screen. The fan or blower $9 is provided with an intake opening RG2 having louvers 164 thereon for admitting air into the intake of the fan which is driven by a suitable electric motor 106 with the fan being driven by a belt 198.

In operation, fuel enters the combustion chamber of the burner assembly 72 through the float type carburetor 32 with the carburetor being connected with a suitable fuel tank or other fuel supply by any suitable means (not shown). Air is supplied for combustion by the blower 84 and is taken in through the inlet louvers 164. This air is forced into what may be termed a plenum chamber between the peripheral wall of the primary combustion chamber and the baffle 78 and then passes around the bottom of the baflie 78 up into the chamber between the baflie 73 and the burner 72. This allows the pressures to equalize thus forming an even pressure distribution of the air around the burner. The air enters the burner assembly 72 through the combustion air openings 76 at a uniform velocity because the air pressure is fairly uniform.

Combustion takes place in the burner 72 and the hot combustion products rise through the primary heat exchanger 38 which is heated from convection from the hot gases and is also heated by flame radiation. In order for the hot gases to exhaust from opening 50 they must rise into the primary heat exchanger 33, make a right angle turn into the secondary heat exchanger 40 and pass along one side surface of the baflie plate 42, turn around the end edge of the baffle plate 42 and back towards the opening 5%} for discharge therethrough.

The air to be heated and which cools the heat exchanger enters through the louvers and enters the blower and then discharges the air at a higher static pres sure into the cabinet above the partition wall 90. Due to the position of the blower and the orientation of the opening 92, some of the air follows a path upwardly around and over the secondary heat exchanger thus cooling the side walls of the cabinet and also the top. Other portions of the air travel over and around the primary heat exchanger thereby causing the transfer of heat from the surface of the heat exchanger to the air. This air travels in a downward direction during the final stages of movement over the peripheral surfaces of the heat exchanger and all of the air then exits through the grill on the side and front half of the heater. By forcing this blanket of air over the heat exchanger, the top of the heater remains relatively cool. In fact, the top of the heater is only approximately 15 F. above ambient temperature. Thus, the top may be provided with a cover of Formica or any other similar laminated material for use of this surface for other utilitarian purposes.

By using a relatively large blower such as a blower 10 inches in diameter driven by an electric motor, a large volume of air can be furnished without the noise of a high speed blower. By using a larger blower, the noise level is much less for the volume of air furnished than is in the conventional type space heater using a high speed blower. Further, the efliciency is increased because of the extra heat exchanger surface and the distance the hot gases have to travel before they leave the heat exchanger. This causes a lower stack temperature, therefore, increasing the efficiency. A lower stack temperature is also accomplished by using forced convection for the entire heat transfer process instead of utilizing free convection as is done in most space heaters. Instead of the heated air rising and going directly to the ceiling, this air is forced out towards the bottom and sides of the unit thereby remaining on or adjacent the floor longer and heating the bottom of the room before the hot air rises to the ceiling. In this construction, all of the heated air is forced out of the bottom and sides of the heater instead of just a small portion of the air as in the case of conventional space heaters.

Another feature of the heater is the easy method of removing the burner. The burner is mounted on a separate plate or flange disposed in the heat exchanger with this flange having an opening which allows the burner 72 to extend downwardly into the chamber formed by the baflle 78 and is mounted by the lip of the burner resting on the flange which may be more securely anchored by sheet metal screws or the like. Thus, it is only necessary to disconnect the fuel inlet and remove the fastening devices and then lift the burner out through the door since the door will be large enough to allow this to be done with a minimum of effort.

Any suitable controls may be provided for the fuel supply mechanism, the air circulation mechanism as well as the ignition mechanism for the burner. A master thermostat control may be provided or the device may be manually operated whenever desired. Further, the size of the unit may vary depending upon the output requirements thereof and the unit may be decorated in any suitable manner compatible with the interior of a room or the like.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

A space heater comprising a generally parallelepiped casing, a substantially L-shaped heat exchanger assembly disposed in said casing, bracket means supporting the heat exchanger assembly in spaced relation to the casing, said heat exchanger assembly including a substantial vertically disposed primary heat exchanger and a substantially horizontally disposed secondary heat exchanger disposed at the top portion of the primary heat exchanger and being communicated therewith, a generally L-shaped partition wall disposed in said casing and including a vertical wall in spaced relation to the primary heat exchanger and a horizontal wall spaced below the bottom wall of the horizontal secondary heat exchanger thereby defining a compartment with a portion of the bottom and a portion of one wall of the casing defining the exterior walls of the compartment, a convection air circulating blower mounted in said compartment, the exterior wall of the casing which cooperates with the partition to form a compartment having a louvered opening therein for intake of circulating air, said vertical primary heat exchanger having a bottom wall spaced from the bottom wall of the casing and an inwardly extending flange spaced vertically from the bottom wall of the primary heat exchanger, a tubular member communicating the compartment formed by the partition wall and the space between the bottom wall of the heat exchanger and the inwardly extending flange therein, a blower means mounted in said compartment formed by the partition wall and communicated with the tubular member for introducing combustion supporting air into the space between the bottom Wall of the heat exchanger and the inwardly extending flange therein, said inwardly extending flange in the primary heat exchanger defining an enlarged opening, burner means positioned to direct flames and products of combustion toward said enlarged opening, said secondary heat exchanger including a flue pipe communicated with one side wall thereof adjacent its point of communication with the upper end portion of the primary heat exchanger, a longitudinal baffle wall centrally disposed in said secondary heat exchanger with one end edge of the baflie being spaced from the outer end wall of the secondary heat exchanger, a closure wall extending between the end of the bafile adjacent the primary heat exchanger and the side wall of the secondary heat exchanger having the discharge flue communicated therewith thereby forming a discharge for hot combustion products through one-half of the secondary heat exchanger along one side of the baflle, around the end of the baffle and back along the other side of the baffle and out through the discharge flue, the horizontal Wall of said partition wall having an enlarged opening for discharging convection air from the circulating blower completely around the periphery of the secondary and primary heat exchangers thereby cooling the interior surface of the casing and picking up heat from the exterior surface of the heat exchanger assembly, said casing having an enlarged screened opening extending throughout the length thereof and across one end wall thereof and a portion of the side wall in remote relation to the louvered air intake opening for discharge of heated air over a relatively large area for thoroughly mixing the heated air with the ambient air in a room or the like.

References Cited in the file of this patent UNITED STATES PATENTS 1,725,510 Fiske Aug. 20, 1929 2,043,429 Dobbins June 9, 1936 2,205,451 Woolery June 29, 1940 2,243,916 Mueller June 3, 1941 2,250,893 McCall July 29, 1941 2,306,443 Howard Dec. 29, 1942 2,453,029 Mills Nov. 2, 1948 2,550,854 Olds et al. May 1, 1951 2,592,396 Dahlstrom Apr. 8, 1952 2,923,287 Murphy Feb. 2, 1960