US2102870A - Evaporator - Google Patents

Description

Dec 21, 1937.

E. WITZEL EVAPORATOR Filed May 16, 1935 2 'Sheets$heet l In uemor Wit) 193 MK attorney.

IE. WlT ZEL Dec. 21, 1937.

\ EVAiORATOR Filed May 16, 1935 2 Sheets-Sheet 2 11121621102 Wiv- 53 @519 TTOI I" [1 31.

Patented Dec. 21, 1937 UNITED STATES EVAPORATOR Ernst Witael, Racine,

Radiator Company,

Application May 16,

6 Claims.

The object of the present invention is to economically distribute the refrigerant to the various coils in the evaporator.

In devices of the class, it is customary to dis- 5 charge the liquid refrigerant by means of an expansion valve, into a common header having individual tube outlets which lead to the various individual coils of the evaporator. Frequently the header is made long enough to receive a; direct connection from the inlet end of each individual coil.

It has previously been diflicult to distribute the refrigerant equally to each coil, partially because some of the refrigerant flashes into vapor immediatelyit enters the header.

A- mixture of vapor and liquid or liquid only, conceivably would be dimcult to distribute to large spaced apart outlets, for various reasons. Applicant provides means whereby the refrigerant is discharged from the expansion .valve into a small distributing chamber having suitably positioned, closely spaced, relatively small outlets. There will, therefore, be little or no expansion of the refrigerant while passing through. this chamber. I also provide means whereby there will be suitable turbulence in the, chamber to further cause equal quantities of the liquid, and gas, if any, to pass into the various outlets.

One of the objects of this invention is to provide secondary distributing heads, whereby the refrigerant first distributed is conducted to individual secondary heads, where it is again divided in the same manner as in the first head. Thus when there is a large number of evaporator coils, particularly if their inlets are at varying distances from the primary distributing head,

' expansion is largely avoided until the refrigerant in liquid form enters the inlet end of the coils.

To these and other useful ends, my invention resides in features of construction and combination of parts or their equivalents, as hereinafter set forth and claimed and shown in the accompanying drawings in which;

Figure l is a front sectional view of one form ure 3.

Figure 2 is a front view of a modification showing a primary distributing head and secondary heads in section and a fraction of a conventional evaporator.

Figure 3 is a sectional view of the header shown in Figure 1, taken on line 3 of Figure 1.

Figure 4 is a front elevation of an evaporator equipped with one form of my invention.

Figure 5 is a sectional view of my secondary of my distributing head taken on line of Fig-- Wis., assignor to Youn Racine, Wis.

1935, Serial No.

header as shown in Figure 4, taken on line 5 of Figure 4.

As thus' illustrated in Figures 1- and 3, the header housing is designated by numeral Numeral H designates afraction of an expansion 5 valve or a restricted connection from the receiving tank. This member is usually screw threaded into the header, as indicated, and a slightly projecting nozzle I2, is frequently supplied as indicated, the header having a chamber l3 and a bottom seat l4 which is preferably formed in the shape of an inverted cone. In this design, which is suitable for a four coil evaporator, four orifices l5 are drilled through the seat 14 and closely positioned, preferably in a small circle around the apex of the cone. One orifice is provided for each coil in the evaporator.

Orifices I5 are as closely spaced as it is possible to drill, however they diverge outwardly.

making it possible to intersect the openings provided for the outlet tubes 22, 23, 24, and 25,-each of which leads to the inlet of one of the four evaporator coils.

I provide a cap 26, for the outlet opening formed by chamber l3 on the inner end of which a cone shaped projection 21 is, preferably, provided. The apex of projection 21 extends in front of the nozzle l2, thus to break up the entering refrigerant, cause the necessary turbulence and reduce the area of chamber l3.

Clearly the header shown in Figures 1 and 3, may be designed to accommodate any reasonable number of evaporator coils; however I illustrate, in Figure 2, a modification wherein each orifice in the conical seat, may serve two evaporator coils by providing secondary headers as follows: The primary header 30 is, preferably, similar to that shown in Figures 1 and 3, wherein the conical seat is provided with orifices 3| which are large enough to serve two or more evaporator coils as indicated. Outlet tubes 32, 33, and 34 each leads to a secondary header 35 and each secondary header is provided with two orifices 36 and 31, which intersect openings provided for tube outlets 38 and 39, each of which is adapted to be connected to the inlet of an evaporator coil. Orifices 36 and 31 are preferably about the size of orifices IS in header ll] of Figures 1 and 3 and orifices 3! are somewhat larger.

Thus it will be seen that a larger number of coils may be served by the header in the design shown in Figure 2, than would be possible in the design shown in Figure 1, in addition to other tion with Figures 4 and 5.

" have a concave shape or be made fiat.

In the design of the evaporator shown in Figure 4 the coils are positioned horizontally. Thus some of the coil inlets may be a considerable distance from the primary header. Applicant endeavors first to equally distribute the refrigerant into the outlet tubes 4 I, 42, and 43, each of which leads to a secondary header 44, the primary header 40 being similar to header 30 of Figure 2, except in the position of the outlets.

Secondary header 44, is provided with a chamber 45, which also answers as a receptacle for tubes 4|, 42, and 43. A cone shaped seat 46, is provided. Two orifices 48 and 49 are drilled into the seat as in the other headers, intersecting the outlet connections for tubes 50 and 5|.

.Tube 50, leads directly into one of the evapo rator coils and tube 5| is adapted to lead into the adjacent coil. Thus each coil of a pair of coils is served by an orifice in the secondary header and each secondary header is served by a suitable orifice in the primary header 4!) in a manner which will insure equal distribution to the various coils of the evaporator, regardless of their position or distance from the primary header.

Obviously applicant's primary header may be adapted to serve any reasonable number of coils and when used to distribute refrigerant to the coils through secondary headers the distribution therefrom will be equally uniform.

The cone 21 may, obviously, be dispensed with or differently shaped, and further the expansion valve may be placed in the position now occupied by the cap 26. The cone shaped seat may For the present purpose it will not be necessary to enumerate all of the minor modifications contemplated by applicant because each header may be variously designed and used separately or combined on any sort of evaporator. For example, two or more primary headers may be adapted to serve certain coils of an'evaporator or a single header may be made to serve two or more individual evaporators.

Clearly the size of the orifices in either header will depend upon the diameter and length of the evaporator coils. The diameter of the tubes leading from either header, particularly from the primary to the secondary header, may be quite small thus to largely avoid expansion of the refrigerant in its passage from the expansion valve to the coils. The pressure in the high side of the system will also be a material factor in determining these sizes. Applicant's device may be used under certain conditions whereby what is termed an expansion valve may be supplied with a non-restrictive outlet to the header whereby the orifices would in fact, be the expansion nozzles. In the design shown in Figure 2, orifices 36 and 31 could be made to act almost exclusively as expansion outlets provided orifices 3| were made relatively large. p I

Having thus shown and described my invention I claim 1. Ida device of the class described, comprising an evaporator having a number of coils, a refrigerant distributing head having a chamber having a seat in its bottom in the shape of an inverted cone, small outlet orifices closely spacedaround the apex of said seat, each having 2. In a device of the class described, comprising an evaporator having a number of coils, a refrigerant distributing head having a chamber and an inverted cone shaped seat in its bottom,

outlet orifices closely spaced around the apex -of said seat, each having an outlet connection to the inlet end of one of said coils, an inlet to said chamber adapted to receive the refrigerant, whereby the refrigerant is metered into, said coils and permitted to expand thereafter.

' 3. In a device of the class described, comprising an evaporator having a number of coils, a refrigerant distributing head having a relatively small chamber, closely spaced small outlet orifices in the bottom of said chamber, each having an outlet connection to the inlet end of one of said coils, an inlet in said chamber adapted to receive the refrigerant, a removable closure for said chamber having a projection which extends into the direct path of the refrigerant after leaving said inlet, whereby the refrigerant is caused to be agitated before reaching said orifices. I

4. An evaporator distributing head comprising, a relatively small chamber having closely spaced orifices in the bottom thereof, each having a connection to an outlet tube, a refrigerant inlet to said chamber and a removable projection which lies in the direct path of the incoming refrigerant to thereby cause turbulence and an equal distribution of refrigerant into said orifices.

5. An evaporator of the class described, comprising a number of coils, a primary header having a chamber with an inverted cone shaped bottom which is provided with a number of spaced apart outlet orifices positioned around the apex thereof, each orifice having a connection to a secondary header chamber, each said secondary header chamber having an inverted cone shaped bottom which is provided with a number of spaced apart orifices positioned adjacent the apex thereof, each of said last named orifices having a connection to one of said coils, a refrigerant inlet in said primary chamber whereby the refrigerant is equally metered into said secondary chambers and then equally metered from said secondary chambers to one of said coils.

6. In a device of the class described,'compris ing an evaporator having a number of individual coils, the combination ofa primary header having a chamber and an inlet for the reception of a refrigerant, a plurality of closely spaced outlet orifices concentrically positioned in the bottom of said chamber, a number of secondary headers each having a chamber being operatively connected to one of said primary header outlets, a number of closely spaced concentrically positioned outlet orifices in the bottom of said secondary header chambers, each of said secondary outlet orifices having a connection to the inlet of one of said coils, whereby the refrigerant is equally distributed into said secondary header chambers and then equally distributed to said individual coils.

ERNST WITZEL.

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