US2855840A

US2855840A - Inductor

Info

Publication number: US2855840A
Application number: US454163A
Authority: US
Inventors: Lance L Simmons
Original assignee: American Radiator and Standard Sanitary Corp
Current assignee: American Radiator and Standard Sanitary Corp
Priority date: 1954-09-03
Filing date: 1954-09-03
Publication date: 1958-10-14
Anticipated expiration: 1975-10-14
Also published as: BE543730A; FR1143261A; CH326457A; GB787604A

Description

ca-44,1958 I SIMMONS 2,855,840

INDUCTOR Filed Sept. 3. 1954 3 Sheets-Sheet 1 Ema-@L v INVENTOR, inn/c5 L SIMMo/vs ,4 TTORNESJ 'L. L. SIMMONS INDUCTOR 3 Sheets -Sheet 2 Find Sept. 5. 1954 w a M Q IL 4 0 owl WA M x a a,

United States Patent INDUCTOR Lance L. Simmons, Detroit, Mich., assignor, by mesne assignments, to American Radiator & Standard Sanitary Corporation, New York, N. Y., a corporation of Delaware Application September 3, 1954, Serial No. 454,163

9 Claims. (Cl. 98-68) The present invention relates to an air conditioning unit, and more particularly to such a unit wherein primary air is used to induce a flow of room air through a heat exchanger, the resultant mixture being discharged into the space being conditioned.

It is a principal object of the present invention to provide an air conditioning unit wherein primary air is used under optimum conditions to assure a high rate of efliciency in inducing a flow of air through a heat exchanger.

It is another object of the present invention to provide an air conditioning unit which is flexible in use and readily adaptable to various installation and operation conditions. i

It is a further object of the present invention to provide an induction type air conditioning unit which is eflicient in operation and relatively simple in design.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

In the drawings:

Fig. 1 is a front elevation of a six tube pass serpentine coil air conditioning unit embodying the present invention.

Fig. 2 is a view similar to Fig. l with the front plate removed.

,Fig. 3 is a sectional elevation taken along line 3-3 in the direction of the arrows, Fig. 2.

Fig. 4 is a fragmentary sectional view taken along the line 4-4 in the direction of the arrows, Fig. 3.

Fig. 5 is a fragmentary view showing the arrangement with a four tube pass coil unit.

Fig. 6 is a fragmentary view of another embodiment showing a six tube pass coil unit utilizing a novel drain trough structure.

Fig. 7 is a view similar to Fig. 6 showing the particular drain trough structure used with a four tube pass coil unit.

Fig. 8 is a sectional elevation of one of the coil end covers used with the air conditioning unit of the present invention.

Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Referring to the drawings, the air conditioning unit of the present invention includes a housing 10 having a primary air inlet 12 which is adapted to be affixed to a conduit connected with a source of air under pressure. The primary air inlet 12 is at one end of a wind box 14, and a similar opening and collar is provided at 16 at the opposite end of the wind box. Either of these openings may be used as the primary air inlet, and the other opening is provided ice with a cap containing a wind box pressure tap. This permits the primary air line to be brought in from either side of the unit. The primary air supply is controlled by a non-resonant butterfly valve (not shown) located on the air inlet side of the unit. Thus, the primary air nozzle pressure may be adjusted to the desired value by moving the butterfly valve to the proper position.

The primary air is moved from the air inlet 12 into the wind box 14 and through a slotted internal distributor baflle 18 into the internal main air feed duct 20. It has been found that two slots in the distributor baflle 18 provided respectively at points one-quarter and three quarters the length of the wind box 14 produce good distribution of pressure so that the jet of air issuing from the longitudinally elongated primary air outlet opening 22 will have substantially uniform pressures throughout its length. As shown in Fig. 3 outlet opening 22 is located at the juncture between wind box wall section 19 and planar extension 17 of backwall 24. Although extension 17 and wall section 19 do not extend in the same plane they may be considered to broadly form one wall of box 14.

Internal surfaces 21 of the wind box 14 and primary air passage 20 preferably are treated with material having thermal insulation and sound attenuation properties to minimize heat loss from the apparatus and to reduce noise of operation.

Referring to Fig. 4 it will be seen that bosses 26 are provided for controlling the width of opening 22 with accuracy. The effective area of opening 22 and the velocity of the primary air with respect to the area of heat exchanger 32 may be controlled by a plastic insert 28 having spaced longitudinally elongated openings 30. It will be understood that the term longitudinal as used herein refers to directions at right angles to the plane of Fig. 3 in the drawings (i. e. parallel to the longest dimension of the air conditioner unit).

It will be noted that the backwall 24 includes a flat wall portion 23 extending to a point 35 to cooperate with longitudinal wall portion 50 in forming a restricted throat passage 42. A heat exchanger 32 is angularly disposed in spaced relation to the backwall. The heat exchanger 32 shown in Fig. 1 has a six tube pass coil heat exchange element 34. Fins 36 are provided around the coil which is connected to a suitable source of coolant or heating fluid.

As previously stated, the room air is induced through the room air inlet 38 and heat exchanger 32 by the jet of primary air. The general theory of flow induction is well known. A stream of fluid issuing at high velocity into a relatively quiet fluid body will impart a portion of its energy of motion to the quiet fluid body and set it into motion in the direction of the original stream or jet. This exchange of energy takes place at the boundary surface of the stream or jet. It has been found by experiment that the total angle between the sides of a confined non-inductive jet is approximately 3 5 whereas the angle between the sides of an air inducing jet issuing into free air is between 6 and 7. Any conditions which vary this angle beyond the indicated limits will limit induction or entrainment.

The air conditioning unit of the present invention utilizes this phenomenon in its construction. The jet of pri mary air issuing from nozzle 22 hugs the smooth metal backwall 24 and the form of the jet is defined by the backwall which although preferably curved at 35 as shown, can be either vertical or sloped. The heat exchanger 32 is so positioned with respect to backwall 24 as to form the angle best suited to the expansion of the jet through induction of room air through the heat exchanger. The inner edges 25 of the heat exchanger coils 27 extend at an angle of about three degrees with respect to wall 24 when measured in directions from the nozzle opening. It is believed that edges 25 have a tendency to confine the jet from nozzle 22 so as to minimize eddy losses between the primary air and secondary air. Test results indicate that maximum amounts of induced air are obtained when edges 25 are in their illustrated positions with respect to back wall 24.

Positioned directly above the induction portion of the unit is the evase 40 of a Venturi formed by diverging

wall portions

47 and 48. This Venturi includes the restricted throat 42. The mixture of primary air and induced room air is passed into the throat 42 and then out the Venturi construction through the outlet 44. This increases the efiiciency of the air induction. It is known that a Venturi has minor effect in air induction when there is no resistance to the flow of the secondary or induced air, but a Venturi has definite advantages when there is resistance to secondary air flow as in the present case with the heat exchanger.

The backwall 24 works smoothly into the Venturi construction at 35 and permits less angularity of the heat exchanger 32.

The fore plate 46 is divided into two

wall portions

48 and 50. Entry and removal of the heat exchanger 32 with respect to the assembly is facilitated by this construction. When the heat exchanger is in the assembled position, the fore plate 46 is joined through

wall portions

48 and 50 by suitable means such as the bolts 52.

A modification of the fore plate construction is shown in Fig. 5. In this embodiment a four tube pass coil rather than a six tube pass coil heat exchanger is used. Fore plate wall portion 50 is elongated to compensate for the smaller height of the four tube pass coil heat exchanger.

A further modification is shown in Fig. 6 of the drawings. A six tube pass coil unit is shown. In this instance member 50b is curved over the end of heat exchanger 32b to provide a narrow drain trough 55b. An outlet pipe 54b is used to pass ofi collected moisture. The position of the air conditioner unit when used horizontally can be demonstrated by placing Fig. 1 of the drawing on its side. Moisture which is condensed on the coils 34 will rundown the sloping heat exchanger 32 into drain trough 55]) (Fig. 6) and through outlet pipe 54b. Thus, the unit may be horizontally disposed without the necessity of using a full width drain pan.

Fig. 7 shows the construction of Fig. 6 modified for use with a four tube pass coil heat exchanger. As in Fig. 5, the fore plate section 50c is elongated to accommodate the shorter heat exchange unit.

A coil end cover 56 is shown in Fig. 8. It consists of a housing 58 and an attaching flange 60. One of these covers is placed over the return bends of the coils on each side of the air conditioning unit. These covers drain condensate into the main drip pan such as 62 (Fig. 3).

From the foregoing, it will be seen that I have provided a simple and efiicient induction type air conditioning unit, which is extremely versatile. The unit provides a unique, aerodynamically correct combination of a primary air nozzle, expansion chamber and Venturi conversion piece. The combination produces a high induction ratio of secondary air to primary air with minimum primary air nozzle pressure at low noise level.

Having thus described my invention, I claim:

1. An air conditioning unit comprising an elongated primary air wind box having a primary air inlet; said wind box also having a longitudinally elongated outlet opening in one of its longitudinal walls; a first substantially flat longitudinal wall portion initiating at the outlet opening and extending away from the wind box parallel with the major axis of the elongated opening; a second longitudinal wall portion located adjacent the downstream limit of the first longitudinal wall portion to cooperate therewith in forming a restricted passage for receiving primary air and secondary air; the space between the second longitudinal wall and wind box constituting a secondary air inlet; and a heat exchange member located in the secondary air inlet in substantial parallelism with the first wall portion.

2. The combination of claim 1 wherein the heat exchange member includes a series of finned coils, the edges of the fins closest to the first longitudinal wall portion defining a plane diverging slightly from said first longitudinal wall portion in a downstream direction.

3. The combination of claim 1 wherein the heat exchange member includes a series of finned coils, the edges of the fins closest to the first longitudinal wall defining a plane diverging from said first longitudinal wall portion in a downstream direction at an angle of about three degrees.

4. The combination of claim 1 and further including third and fourth longitudinal wall portions diverging from the downstream edges of respective ones of the first and second wall portions to define a Venturi for handling the primary air-secondary air mixture.

5. The combination of claim 1 and further including third and fourth longitudinal wall portions diverging from the downstream edges of respective ones of the first and second wall portions to define a Venturi; said heat exchange member including a series of finned coils, the edges of the fins closest to the first longitudinal wall portion extending substantially in line with said fourth wall portion.

6. The combination of claim 1 wherein the wind box is provided with a longitudinal partition extending between the primary air inlet and outlet opening, and longitudinal openings are provided in the partition for distributing the air evenly to all points along the outlet opening.

7. The combination of claim 6 wherein the partition includes a first wall section extending from a point adjacent the outlet opening and a second wall section extending angularly from the first wall section in a direction away from the outlet opening; and the partition openings are formed in the second wall section.

8. The combination of claim 1 wherein one wall of the wind box is at least partially defined by a planar extension of said first longitudinal wall portion, and one edge of said outlet opening is formed by said planar extension.

9. The combination o f'claim 1 wherein one exterior face of the wind'box is trough-shaped to receive condensate from the heat exchange member; the heat exchange member includes a series of fins having their upstream edges extending upwardly from the wind box toward a point overlying the trough-shaped face; and a drain trough is provided at the upstream end of the second longitudinal wall portion; whereby condensate is collected whether the unit is positioned with the upstream edges of the fins located in a generally horizontal plane or in a generally vertical plane.

References Cited in the file of this patent UNITED STATES PATENTS 1,995,667 Cano Mar. 26, 1935 FOREIGN PATENTS 379,430 Great Britain Sept. 1, 1932 884,634 France Aug. 23, 1943 704,447 Great Britain Feb. 24, 1954