US3309503A - Electric sauna bath heater - Google Patents

Description

March 14, 1967 new ET AL ELECTRIC SAUNA BATH HEATER Filed Jan. 16, 1964 HHHLHN mm \m nvvzzmorz Gweoau A4. Dow la W514 7. SWENJO/V MI I, Me- 5 0% Arrwewsxs United States Patent 3,309,503 ELECTRIC SAUNA BATH HEATER Gordon M. Dow, North, and Lowell T. Swenson, Thief River Falls, Minn., assignors to Dow-Key Company, Inc, Thief River Falls, Minn., a corporation of Minnesota Filed Jan. 16, 1964, Ser. No. 338,086

12 Claims. (Cl. 219-378) This invention relates generally to baths and is more particularly directed to apparatus for providing a saunatype bath which originated in Finland.

An object of the present invention is to provide an improved apparatus which forms a part of a complete installation which may be installed, for example, within.

the average home and which may 'be constructed so that it may be acquired and installed within the range of prices attractive to the average homeowner who is interested in obtaining the benefits of a sauna bath located in his own home.

Another object of this invention is to provide equipment for utilization in a sauna bath which is relatively inexpensive to purchase and operate.

A further object of this invention is to provide improved apparatus for use in individual enclosures, or cubicles, for providing sauna-type baths.

A still further object of this invention is to provide an improved heater apparatus for use in a sauna-type bath.

A further object of this invention is to provide a safe heater apparatus for a sauna-type bath.

It is a still further object of this invention to provide a heater for use in a sauna-type bath enclosure which provides a more accurate control over the atmosphere which must be created to enjoy the benefits of a sauna-type bath.

These and other objects of our invention will become apparent from a consideration of the appended specification, claims and drawings, in which:

FIG. 1 is a side elevational view, partly broken away, of a heater which may be utilized in a sauna-type bath installation.

FIG. 2 is a top plan view of the heater shown in FIG. 1.

FIG. 3 is a side sectional view taken along section line 33 in FIG. 1.

FIG. 4 is an electrical schematic drawing illustrating one embodiment of control circuitry which may be utilized in connection with the apparatus shown in FIGS. 1, 2 and 3. g

FIG. 5 is a perspective sketch of a complete saunatype bath apparatus.

' Referring now to the drawings, and particularly to FIG. 5, there is shown a complete sauna bath installation in which an enclosure, indicated generally by thereference numeral 50, is provided with an access door 52 and a platform, shown as a series of steps, 51 upon which the user of the sauna bath installation may be seated during the time the bath is in progress. A heater, indicated generally by the reference numeral 10, and having acontrol box assembly 40 adapted for connection to a suitable source of electrical energy throughconductors 14, is in position below a source ofliquid 12, having avalve 13 which is adapted to regulate the flow of liquid down onto the top of the heater apparatus 10. In many uses of our apparatus the fluid used to create the desired atmosphere may easily be applied manually to the top of heater from a suitable source or container (not shown).Control box 40 is also connected to a wall-mounted temperature responsive means 11 for purposes to be explained below.

As will become apparent from a consideration of the operation of the apparatus shown in FIGS. 1, 2, 3 and 4, explained in detail below, the general operation of the complete sauna bath shown in FIG. 5 is as follows: the subject, or user, enters enclosure 50' and energizes the heater apparatus 10, through suitable means (not shown) and the temperature in the enclosure rises to a point determined by the setting of the temperature responsive apparatus 11 and heated air, during this time, is circulated through heater apparatus 10 by the use of a blower 15', which takes air from the lower portion of the room and passes it through heater apparatus 10 and vents it back into the room through the plurality of slots 21 shown at the sides of heating apparatus 10. From time to time, and as desired by the subject, suitable amounts of a liquid, for example water, are added to the top of heating apparatus 10 and the liquid is immediately vaporized and re-expelled and added to the atmosphere inenclosure 50. The temperature of the air therein is held at a predetermined level and, as will be explained below, the vapor is generated at a substantially constant predetermined temperature so that the subject may effect a balance and maintain the desired atmosphere, as determined by any particular subject, within the enclosure for as long as is desired.

Referring now to FIGS. 1, 2, and 3 of the drawing, heating apparatus 10 is comprised of anouter housing 20 which is open at its top and is provided with a plurality of louvered slots 21 near the upper outside periphery to allow for the escape of heated air as will be explained below.Outer housing 20 is also provided with a plurality oflegs 22 which are provided and adapted to support heating apparatus 10. A second, orinner housing 30 is suitably mounted withinouter housing 20.Inner housing 30 may be comprised of suitable material which exhibits low thermal conductivity.Inner housing 30 is formed with an upwardly extending opening at its top and with at least one inlet opening 55 and at least one outlet opening 54 at the bottom end. First and second chambers are defined on the interior ofinner housing 30 by the suitable positioning and fastening of a heating means indicated generally by thereference numeral 25. Heating means 25 is comprised of a substantially flat "central portion which extends in proximity to and engages the sides ofinner enclosure member 30 so as to define the upper and lower chambers noted above. A plurality of generallyconical protuberances 26 extend upwardly from the top surface of the central portion of heater means 25 and lie within the upper chamber andenclosure 30. A like plurality of generally conically shaped protuberances depend downwardly fro-m the lower surface of the center portion ofheater member 25 to fill the lower chamber andinner enclosure member 30. A resistance heating element is shown positioned in anappropriate channel 27 formed in the center of the center portion ofheater member 25. This resistance heating element may be formed integrally withheater member 25 by a suitable process, for example casting. It has further been noted that a suitable material forheater member 25 is a high temperature alloy of aluminum which is selected to withstand the normal operating temperatures of the heater unit. 'It may further be noted thatinner housing 30 may be comprised of a pluraltiy of layers ofmaterial 31 and 32 to provide a housing 'which has a low thermal conductivity coefiicient. For example, layer 31 may be comprised of a suitable dielectric material which has low heat transfer characteristics such as powdered alumina, asbestos or the like. A condition responsive means 16 may be utilized to sense the temperature on the top surface of the center portion ofheating member 25 and is shown, by way of example, as a snap-acting thermostat which may be utilized to directly control the flow of current to heatingelement 17 as shown in FIG. 4. Aperforated cover member 24 having a plurality ofperforations 41 is shown in position on the top of the top chamber in inner housing memberfih and the spaces between the upwardly dependingprotrusions 26 within the upper chamber may be filled with a suitable material having high heat transfer characteristics, for example, marble chips or aluminum balls or shavings; It should be noted thatinner housing 30 is divided into two chambers by suitable mounting means (not shown) forheater member 25 which will provide a fluid type seal between the upperand lower chambers. A control box .40 is attached toouter housing 20 and contains suitable devices and apparatus for providing the interconnections between the conductors of the various components com-prising our invention. Upon becoming familiar with the principles of our invention, and with a consideration of the schematic diagram of FIG. 4, the illustrated apparatus and may others will become apparent to those skilled in the art for controlling the operation of our apparatus. In FIG. 4 there is shown a condition responsive means 11, also indicated by the reference numeral T connected tocontrol box 41 through a pair of conductors; a pair of terminals14 adapted for connection to a suitable source. of electrical energy; a pair of conductors 66 connected to blower means 15; a pair of conductors connected to resistance heating element17; and a pair of conductors connected to condition responsive means '16, also indicated by the referencenumeral T A blower 15 includes aninlet 56 and an outlet 57 which is shown attached toinlet 55 oninner housing member 30 and the flow of air is driven byblower 15 as indicated generally by the arrows, throughblower 15, into the lower chamber on inner housing 39, around the staggered downwardly dependingprotrusions 28 onheater member 25, out of outlet opening 54 and around the bottom and up the sides of the inside ofhousing member 20 and thence through louvered openings 21 into the interior of the enclosure in which the heating apparatus is utilized. It may be desirable under some circumstances, to maintain a predetermined relationship between the area ofinlet openings 55 andoutlet openings 54 to provide for efficient transfer of heat energy to the air as it passes through the lower chamber oninner housing 30. A smaller area on the outlet openings provides for a form of time delay which serves to increase the temperature of the air leaving the outlet opening.

While we have shown and described our heater in a particular embodiment, it is anticipated that other forms of apparatus, such as will be set forth below by way of illustrative examples, will occur to those skilled in the art and it is contemplated that these and other modifications properly fall within the scope of our invention.

In one operative embodiment of our invention, apparatus similar to the inner housing was utilized. Suitable legs or support means were attached directly to a housing having a single insulated wall. The upper and lower chambers as illustrated in the drawing were present and the general overall operating characteristics were substantially thesame as noted above in connection with the illustrated embodiment.

A further modification may be obtained by removing the horizontally oriented lower portion ofinner housing 30 and attaching the outlet of the blower directly to the bottom ofhousing 20. In apparatusconstructed according to this modification, the relationship between the inlet and outlet openings, as noted above, should be retained. The dimensions oflower protrusions 28 may also be modified to place the lower ends thereof in closer proximity to the bottom ofhousing 20.

In FIG. 4 the schematic drawing shows a pair ofterminals 14 connected across a suitable source of alternating current and electricalresistance heating element 17 connected in series with conditionrsponsive means 16 and the energization ofresistance 17 is controlled thereby. In alike manner blower 15 and condition responsive means 11 are connected in series across terminals made in the structure as disclosed, provided such modi-' 14 and the operation ofblower 15 is controlled in accordance with the operation of the condition responsive means. Both of the condition responsive means 11 and 16 may be suitable thermostats which may be adjustable at the will of an operator.

In operation, it has been determined that a suitable temperature for the enclosure of the sauna bath is not less than F. and up to F. or more dependent on the user and this is controlled, upon energization of the heating apparatus, bycondition responsive means 11 which serve to energize anddeenergi ze blower 15 in a manner which will maintain the enclosure at the predetermined desired temperature. It has also been noted that one suitable operating temperature forheatingmeans 25 is a relatively constant 600 F. Heating means 25 not only serves as a source of heat energy for the air which is passed through heating apparatus 10 by means ofblower 15, but also. provides a source of heat energy for vaporizing the liquids adde'd through thetop of the apparatus tothe upper chamber of innerhousing ,30. 1 \It is understood that 'suitable modifications maybe fications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described ourv invention, what we claim' to be new and desire to protect by Letters Patent is:

1. A heater, for sauna bath enclosures comprising in combination: a horizontally disposed, substantially planar heating element having a plurality of upwardlyand downwardly extending protrusions formed integrally therewith; heating means disposed interiorly of said heating element; a housing therefor, said housing being adapted to surround and enclose said heating element whereby said housing is divided into upper and lower chambers, each containing corresponding upwardlyand downwardly extending pluralities of said protrusions, the lower chamber having inlet and outlet openings for the transmission of air therethrough and the upper chamber having an upwardly directed opening for receiving liquids to be vaporized and also containing a plurality of said protrusions on the heating element; and means for supplying air under pressure connected to saidinlet opening,

2. The apparatus of claim 1 in which the upper chamber is filled with particles. of material exhibiting good heat transfer characteristics.

3. The apparatus ofclaim 2 in which the upwardly directed opening in the upper chamber is covered with a perforated screen.

' 4. The apparatus of claim 1 in which said air supplying means comprises a blower mounted on said housing to direct air into the inlet opening.

5. The apparatus of claim 1 in which the area of the outlet opening is less than the area of the inlet opening.

6. The apparatus of claim 1 in which the housing is comprised of material exhibiting low heat transfer characteristics.

7. The apparatus of claim 1 in which the housing is mounted within a second housing and the second housing includes a plurality of openings adapted to receive air from the outlet opening on the housing for said heating element and to vent the same to the atmosphere.

8. The apparatus of claim 1 in which the heating means includes electrical means and a thermostat is mounted on the surface of said heating means for maintaining the same at a predetermined temperature.

9. A heater for a sauna type enclosure comprising in combination: a heater comprised of a horizontally disposed substantially planar base member having a plurality of upwardly and downwardly extending protrusions dependent therefrom, said heater including electrical means therein for heating the same and temperature responsive switching means, on the upper surface thereof, said electrical heating means and temperature responsive switching means being connected in series intermediate a pair of terminals adapted for connection to av suitable source;

receive said heater whereby the downwardly depending protrusions are enclosed in a lower chamber and the upwardly extending protrusions are enclosed in an upper chamber, said lower chamber having inlet and outlet openings and said upper chamber having an upwardly directed opening; a blower, including current responsive motor means, connected to direct air under pressure into the inlet openings in said lower chamber; further temperature responsive means disposed outside of said enclosure and remotely therefrom; and circuit means interconnecting said motor means and said further temperature responsive means to said source of electrical energy.

10. The apparatus of claim 9 in which the protrusions on the heater are in opposed, staggered rows.

11. The apparatus of claim 10 in which the upper chamber is filled with particles of material exhibiting good heat transfer characteristics.

12. The apparatus of claim 9 in which the housing is surrounded by afurther housing having an upwardly di- 2 rected opening and an opening adapted to coact and register with the inlet opening in the lower chamber in said housing and including a plurality of openings in fluid transmitting relationship with the outlet opening in the lower chamber of said housing.

References (fired by the Examiner UNITED STATES PATENTS 1,686,860 10/1928 Hussey 219378 1,932,788 10/1933 Keating 4160 2,096,649 10/ 1937 Rassanen. 2,654,018 9/1953 Sandberg 219-378 2,846,692 8/1958 Baurnann 4160 FOREIGN PATENTS 63,474 4/ 1941 Norway. 74,066 10/ 1948 Norway. 107,901 7/ 1943 Sweden. 122,557 8/ 1948 Sweden. 235,386 7/ 1945 Switzerland.

ANTHONY BARTIS, Primary Examiner.

H. K, ARTIS, Assistant Examiner.

Claims (1)

1. A HEATER FOR SAUNA BATH ENCLOSURES COMPRISING A COMBINATION: A HORIZONTALLY DISPOSED, SUBSTANTIALLY PLANAR HEATING ELEMENT HAVING A PLURALITY OF UPWARDLY AND DOWNWARDLY EXTENDING PROTRUSIONS FORMED INTEGRALLY THEREWITH; HEATING MEANS DISPOSED INTERIORLY OF SAID HEATING ELEMENT; A HOUSING THEREFOR, SAID HOUSING BEING ADAPTED TO SURROUND AND ENCLOSE SAID HEATING ELEMENT WHEREBY SAID HOUSING IS DIVIDED INTO UPPER AND LOWER CHAMBERS, EACH CONTAINING CORRESPONDING UPWARDLY AND DOWNWARDLY EXTENDING PLURALITIES OF SAID PROTRUSIONS, THE LOWER CHAMBER HAVING INLET AND OUTLET OPENINGS FOR THE TRANSMISSION OF AIR THERETHROUGH AND THE UPPER CHAMBER HAVING AN UPWARDLY DIRECTED OPENING FOR RECEIVING LIQUIDS TO BE VAPORIZED AND ALSO CONTAINING A PLURALITY OF SAID PROTRUSIONS ON THE HEATING ELEMENT; AND MEANS FOR SUPPLYIG AIR UNDER PRESSURE CONNECTED TO SAID INLET OPENING.

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