US1998664A

US1998664A - Finned evaporator

Info

Publication number: US1998664A
Application number: US679647A
Authority: US
Inventors: Fred R Erbach
Original assignee: GEN REFRIGERATION CORP
Current assignee: GEN REFRIGERATION CORP; GENERAL REFRIGERATION Corp
Priority date: 1933-07-10
Filing date: 1933-07-10
Publication date: 1935-04-23
Anticipated expiration: 1952-04-23

Description

April '23, 1935. F. R. ERBACH 1,998;664

FINNED EVAPORATOR Filed July 10, 1933 Patented Apr. 23, 1935 UNITED STATES q 1,998,664 I y F1NND\ EVAPoRA'ron Fred R. Erbach, Beloit, Wis., assgnor to General Refrigeration Corporation, Beloit,

poration of Delaware Wis., a cor- Application July 10, 1933, Serial No. 679,647

Claims.

The invention relatesto heat exchanging apparatus and more particularly to finned evaporators for refrigerating systems.

For increasing the heat absorbing surface of evaporators in order to realize the greatest possible heat transfer and maximum efficiency of the refrigerating system it has been .customary to provide the tubing with exterior ns which may be described as washer-like discs having lll openings therein for threading on the tubing and which are suitably secured in spaced relation with each other. Proper construction ofthe finned evaporators requires that the ns be held together rinly to provide a rigid unit preventing one n from becoming displaced with respect vto an adjacent 1in and also that the fins have a secure union with the tubing for the greatest possible heat transfer.

An object of the invention is to provide a finned evaporator in which the discs assembled on the tubing are held in spaced relation by'means integral with the disc to eliminate the use of independent spacer plates vmailing a compact unit of rugged construction. means have contact with the tubing and when spot-welded or galvanized to the tube serve to provide a secure bond, holding the discs to the tubing in proper spaced relation.

A more specic object of the invention resides in the provision of discs having integral spacing prongs punched from the material of the center opening therein and which are cf a length in excess of half the diameter-of the opening so as to space the discs a distance greater than the outside radius of the tube.-

A further object is to provide a disc for the purpose described having spaced prongs punched from the material of the center opening therein and which are substantially equal to the diameter of the opening.

A further 'object is to provide a disc having at least three spacing prongs integral therewith to make a three-point contact with an adjacent fin when assembled on the tube while spacing the fins a distance greater than the outside radius of the tube. This contact between a fin and the spacing prongs of an adjacent iin increases the rigidity of the assembly and permits endwise pressure to be applied, holding the fins in tight relationship preliminary to the bonding of the prongs to the tube.

With these and other objects in view, the invention may consist of certain novel features of construction and operation, as will be more fully described and particularly pointed out in the specification, drawing and claims appended hereto.

In the drawing which illustrates an embodiment of the device and wherein like reference characters are used to designate like parts- The integral spacing Figure 1 is an elevational View showing a section of finned tubing embodying the features of v'the invention;

disc of Figure 2 located on a section of tubing;

`Figure 4 is a plan View of a portion of a disc showing a modied arrangement of the spacing prongs; t

Figure 5 is a vertical sectional view of the disc of Figure 4 with the spacing prongs bent at right angles to thedisc;

Figure 6 is a plan View of a portion of the disc showing still another modied arrangement of the spacing prongs; and v Figure '7 is an elevational view showing the disc if Figure 6 located on the section of tubing.

The section of finned tubing shown in Figure 1 comprises a length of tubing I0, of heat conducting material such as copper, brass or steel, having a plurality of Ifins or discs I2 also of heat conducting material mounted thereon in spaced relation. The discs are provided with a center opening of a diameter substantially equal to the outside diameter of the tubing and a plurality of spacing prongs so that the discs may be assembled on the tubing and maintained in spaced relation by the prongs engaging with the face of the next adjacent disc. As more clearly illustrated in Figures-2 and 3 a preferred method of forming the prongs from the material of the center opening consists in punching openings I4 in the material of the disc of the shape disclosed and which are symmetrically positioned with respect to a horizontal and vertical line passing throughthe center I5 of the disc. The material retained can be described as extending diametrically of the center opening and is severed in accordance with the invention to provide the prong I6 and the bifurcated prong I8. The prongs are bent outwardly from the material of the disc at right angles thereto, as shown in Figure 3, to provide a multi-point support for retaining the discon the tubing with the face of the disc at substantially right angles to the periphery of the v tubing. Further contact between the disc and the tubing is provided by the flange 20 bent from the material of the disc and limited as to depth by the extent of the recesses 22 located on the respective sides of the base of each of the spacing prongs I6 and I8.

Forming the spacing prongs from the material of the center opening in the disc provides integral prongs since the metal cornes from the disc itself and which when severed according to the invention results in integral spacing prongs having a length greater than the radius of the center opening. As the prongs are integral and lspacing plates with their additional cost are eliminated, securing greater economy in` manufacture, while improving the rigidity and compactness of the assembled unit. Also the length of the spacing prongs separates the discs far enough apart for efficient operation while additionally providing a plurality or prongs for more effectively balancing the disc on the tubing and for absorbing endwise pressure` to hold the parts in tight relationship preliminary to the bonding of the prongs to the tubing.

In Figures 4 and 5 the punching of the center opening of the disc 30 is modiiled to provide plurality of prongs, certain of which have a ength substantially equal to the ldiameter of he opening. This is effected by punching open- /ings 32 of substantially semi-circular shape symmetrically disposed with respect to vertical and horizontal lines passing through lthe center $4 of the disc. In blanking the openings 32 material -is retained to form the tabs, The center strip extending diametrically of the openings is severed along the diameter to form the spacing prongs 38 which are trimmed at their ends 38 to provide a prong of the desired length. Prior to locating the disc 30 on a tube the prongs and tabs are bent at right angles to the disc, as shown in Figure 5, providing a multi-point support for the disc by which the same may be held in proper angular relation with the tube ,and which additionally spaces the disc from an adjacent disc a distancel in excess of the radius of the tube but less than the diameter thereof.

In the modified structure of Figure 6 the opening formed in the disc 40 is indicated by the dotted lines 42, all of the material ofthe opening being used in forming thev spacing prongs and securing nanges for the disc. The material within the circle 42 is severed along line 44 to form the spacing prongs 46 and the flanges 4I. When these members are bent at right angles to the disc, as shown in Figure 7, they form the center opening therein and provide in effect a supporting sleeve, the spacing prongs 48 contacting the face of the next adjacent disc to space the same a distance substantially equal to the diameter of the opening while the flanges 48 additionally engage the tubing merely for supporting purposes.

The disc of Figure 2 in which the metal o! the center opening is blanked to form three spaced prongs exceeding in'length the radius of the opening has been found highly eiiicient in use due to the three-point contact which the circumferentially spaced prongs have with the iace of the next adjacent disc. Also the prongs serve to hold the ns rmly on the tube in proper angular position and in true alignment with those of the unit. For various installations, principally those which depend on natural draft for circulating the air, it is desirable that the fins be spaced apart a distance which will not interfere with or hinder in any manner the free flow of air between the fins. Accordingly, the iins of the invention have spacing prongs of a length greater than the radius of the opening as shown in Figure 2 and which may approximate or even equal the diameter of the opening as in the modifications of Figures 4 and 6. It is entirely possible that spacing prongs equal to the radius of the opening will be satisfactory inra number of installations and the invention is therefore to be considered as fulfilling this requirement, as the prongs can be `trimmed to this length and this applies to the disc of Figure 2, wherein the prongs can be shortened without destroying the structural features of the invention.

It is to be understod that I do not wish to be limited by the exact embodiment of the device shown, which is merely by way of illustration and not limitation, as various and other forms of the device will of course be apparent to those skilled in the art without departing frm the spirit of the invention or the scope of the claims.

I claim: l

' 1. A disc for the'purposes described having a center opening therein and prongs integral with the disc and extending from the disc at diametrically opposite points around the opening, said prongs having a length in excess of the radius of 'thebpening and a bifurcated end on one of said prongs.

2. In a heat exchanger, the c '.mbination with a tubular member, of discs carried by said member, each disc having a circular opening therein through which the member extends, and prongs integral with the disc and struck from the metal of said opening for spacing the discs from each other, said prongs having a length greater than the radius of said opening and being spaced around the periphery of said tubular member, certain of said prongs being Joined to the metal of the disc by common means.

y 3. In a heat exchanger, the combination with a tubular member, of discs carried by said member, each disc having a circular opening therein through which the member extends, and prongs integral with the disc and struck from the metal of said opening for spacing the discs from eachv other, said prongs having a length greater than the radius of the opening, one of said prongs having a bifurcated end and said other prongs being located diametrically opposite the space between the ends of said bifurcated prong. 4. In a heat exchanger, the combination wit a tubular member, of discs carried by said member, each disc having a circular opening therein through which the member extends, and prongs integral with the disc and struck from the metal of said opening for spacing the discs from each other, said prongs having a length greater than the radius of said opening, one of said prongs having a bifurcated end forming a plurality of members spaced around the periphery of said tubular member, and said other prongs having a width at its end substantially equal to the space between the ends of said bifurcated prong and being located diametrically opposite said space.

5. In a heat exchanger, the combination with a tubular member, of discs carried by said member, each disc having a circular opening therein through which the member extends, and prongs integral with the disc and struck from the metal of said opening for spacing the discs from each other, said prongs having a length greater than the radius of said opening, one of said vprongs having a bifurcated end providing a plurality' of members spaced around `the periphery of said tubular member, and a flange struck from the metal of said opening and engaging said tubular FRED R. ERBACH.