Heat exchange unit

L. P. SE1FNER ET AL

HEAT EXCHANGE UNIT

May 31, 1949.

Filed Nov. 19, 1945

2,471,784

Sheets-Sheet 1

<img file="US2471784A_D0001.tif" />

L. P. SEIFNER ET AL.

HEAT EXCHANGE UNIT

May 31, 1949.

Filed Nov. 19, 1945

2,471,784

Z Sheets-Sheet 2

<img file="US2471784A_D0002.tif" />

ATTORNEYS

Patented May 31,1949

2,471,784

UNITED STATES PATENT OFFICE

2,471,784

HEAT EXCHANGE UNIT

Louis P. Seifner and Ralph C. Moreau, Seattle, WasM said Moreau assignor to said Seifner

ApplicaiionNovember 19,1945, Serial No. 629,534 (CI. 236—37) its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of a specific embodiment when read in connection 5 with the accompanying drawings, in which:

Kg. 1 is a view in elevation of a heat exchange unit according to our invention, with portions cut away for convenience of illustration;

Fig. 2 is a vertical sectional view through the 10 heater taken on line 2—2 of Fig. 1;

Fig. 3 is a perspective view of the heat exchange housing with portions cut away and shown in section for convenience of illustration; and

Fig. 4 is a diagrammatic view showing the electrical circuit employed in our heat exchange unit.

A heat exchange unit, to be reasonably satisfactory, must have at least two totally distinct characteristics: it must be capable of inexpen20 sive construction and simple installation in a wall of a room; and it must also provide adequate air heating and circulation controllable by conventional means.

Accordingly, a preferred embodiment of our 25 invention, referring to Figures 1 and 2 of the drawings, is constituted by a metallic structure in which is mounted air circulating means, air heating means and air-stream dividing means.

An elongated air conduit 10, formed of sheet 30 metal, extends between an upper fan housing 12 and a lower heater housing 14. The front wall of housing 12 has an opening 16, through which air is drawn by the fan 18, operated by motor 20 that is mounted on cross-bar 24. A deflector 35 22 above the motor and fan tends to turn incoming air downward in the housing 12 and to direct it through the communicating opening 26 in the casing 10. This downwardly induced current of air passes through casing 10 into the 40 multi-chambered housing 14 from the top downward.

The housing 14 comprises a back wall 30, a bottom 31, inner end walls 32 and 33 rising above the bottom and extending forwardly from the 45 back wall. Spaced outwardly from each of the inner end walls 32 and 33, is an outer end wall 34, 35, that also extends forwardly from the back wall 30 and upwardly from the bottom 31. Between the inner end walls is an L-shaped wall, 00 formed of a leg portion 37 and a foot portion 38, preferably integral with each other and joining by the intermediate curved portion 39. The leg portion of the L-shaped wall is spaced apart from the back wall 30, and the foot portion is spaced 05 upward slightly from the bottom 31. This arrangement forms a shielding passage 40, running down behind the L-shaped wall and forward under the L-shaped wall, and air descending into the housing 14 will pass therethrough, and for00 wardly outward through an opening 41 between

Claim.

· Χΐ1ί

Our invention relates to a heat exchange unit and, more particularly, to a device for heating air, which can be installed and concealed in the wall of a room.

It is an important object of our invention to provide a heat exchange unit having upper and lower openings to draw the air from the upper portion of a room, heat it, and discharge it at a lower level in the same room.

A further object of our invention is the provision of a heat exchange unit that may be installed in a wall with a minimum of insulation and without injury to composite wall coverings by reason of vagrant heat rays escaping thereto.

A further object of this invention is to provide a simply and cheaply constructed casing for receiving current inducing and heat exchange means, which casing, is compact enough for concealment in a wall of a room between the studdings of that wall.

The foregoing objects, and others ancillary thereto, we prefer to accomplish as follows:

Walls are employed to form an elongated casing of a size and shape to be positioned in a wall of a room, and said casing has an upper adit opening and a lower discharge opening. The elongated casing is coupled to a heater casing that comprises an L-shaped wall having end walls. Between the end walls, in the crotch of said L-shaped wall, is mounted heat exchange means preferably of an electric resistance type. Secondary end-wall means form an end chamber juxtaposed along each of the first mentioned end walls, and other walls form a long, narrow shielding passage on that side of said L-shaped wall away from the heat exchange means.

In the casing is employed means for Inducing a current of air downward through the casing and into the heat exchange housing, and its various end chambers, shielding passages, and heat exchange chamber, and thence outward into the room.

It is preferable that the walls of the casing and housing and its parts be formed of relatively thin sheet metal, which may be joined in any conventional manner. A baffle plate is disposed in the path of a current of air moving through the casing into the heat exchange chamber, and preferably this baffle plate is slit in a direction running between the end walls of the heat exchange chamber. The end chambers and the shielding passage communicate with a stream of air leaving the heat exchange chamber, which accumulates during its passage through said chambers any vagrant heat that might otherwise escape into the surrounding wall elements.

The novel features that we consider characteristic of our invention are set forth with particularity in the appended claim. The invention itself, however, both as to its organization and

9,471,784 the front edge of the foot portion 38 and a. front flange 42 on the bottom 3 J, as can be seen in Fig. 3. Between walls 32 and 34, running from front to rear in casing 14, is an end chamber 44. A similar chamber 45 lies between end walls 33 and 5 35, and air descending through the casing 10 enters these chambers through upper openings 46 and 47, and travels downwardly therethrough, as indicated in Fig. 1, and thence in under the foot portion 38 of the L-shaped wall, through the 10 openings 46 and 47 in the end walls 32 and 33, to intermingle with air passing down behind and under the L-shaped wall and thence outward.

As can be seen in the drawings, finned strip heaters A and B of the electrical type are mount- 15 ed within the chamber M, defined by the Lshaped wall and the inner end walls, with their ends extending into chambers 44 and 45. Switches F and G are mounted in chambers 44 and 45, respectively, with their operating elements ₂₀accessible outwardly. A cover plate 80, having a grilled portion 51 is placed over the front of housing 14, and it is through this grilled opening that the air leaving the various chambers of housing 14 passes into the room. ₂₅

In Fig. 4, we have shown schematically a wiring diagram suitable for electric operation and control circuits for our heater. The numerals 6® and 61 designate the incoming leads of a 220 volt supply line, by which current is supplied to the ₃q elements A and B, through the two-pole switch F, via a thermostatic switch C that is responsive to room temperatures and calls for heat according to its setting in a conventional manner. A secondary circuit comprises the tap 63 from line 35 and a tap 64 from line 61, and is controllable by the switch G, also of the conventional two-pole type. In this circuit is the motor 20, which is between the poles of switch G. In one of the leads to the motor 2® from switch G is a stack a® switch D that is responsive to heat within the housing 14 and the casing i®. When the switch C calls for heat, and switches F and G are closed, the elements A and B will become hot and the fan 18 will induce a down draft of air through the 4g casing and housing and over the elements as well as through the chambers 40, 44 and 45. Such condition will continue until the thermostatic switch C responds to the rising temperature in the room to which it is responsive and the same 50 will open, breaking the circuit to the heaters A and B. However, the switch D will remain closed as long as there is heat within the casing 90 or housing 84, to which it is set to respond. This will insure a continuation of the air current after 55 termination of the current supply, for as long as is necessary to take away the vagrant rays that nevertheless emanate from the heaters and tend to escape into the chambers 4®, 44 and 45. After this heat is dissipated, the stack switch will nor- a® mally open and the fan circuit will remain off until sufficient heat causes a further closing of the stack switch D.

By reason of the spaced apart positioning of the L-shaped wall comprising portions 37 and 38, 55 with respect to the back wall 30 and bottom 39, a very effective shielding passage of air during operation of the heat exchange unit is placed so as to protect the back wall and bottom and any portion of the building structure adjacent thereto. Operation discloses that no other insulation is required, and that with this simple mechanism effective and safe heating to a high degree of great quantities of air is possible. By means of this construction, extremely economical air heating may be obtained, even with electric current at relatively high cost. The unit itself is simple to construct, to install and to operate.

In the path of the downwardly induced current of air passing from the casing ί 0 to the housing 94, is a baffle plate 70, flanged at 79, in spaced apart relation to the wall 37, and slit to form elongated passage 72 running in a direction between end walls 32 and 33. That portion of the. metal which is turned down to form slit opening 72 and comprising flanges 73 and 74, also functions as baffling plates beneath the baffle. These flanges also function as a nozzle to direct air passing through slit 72 toward heaters A and B.

While we have shown and described particular embodiments of our invention, it will occur to those skilled in the art that various changes and modifications may be made without departing from the invention, and we therefore aim in the appended claim to cover all such changes and modifications as fall within the true spirit and scope of our invention.