US2562600A - Ventilating fan for picture projecting apparatus - Google Patents

Description

y 1951 c. J. CADWELL ET AL 2,562,600

VENTILATING FANS FOR PICTURE PROJECTING APPARATUS Filed D80. 17, 1948 I N VEN TORS 6207291212 ll Cadwell fianlz'ljffl'da'morz Patented July 31, 1951 UNITED STATES PATENT OFFICE VENTILATING FAN FOR PICTURE PROJECTING APPARATUS Application December 17, 1948, Serial No. 65,897

3 Claims. 1 I

The invention relates to a fan for picture projecting apparatus and it is an object of the invention to provide a device of this kind whereby the heat generated by the lamp within the lamp housing in the shell of the machine is quickly dispersed to maintain the machine cool throughout the period it is in operation.

It is also an object of the invention to provide a means for dispersing the heat generated within the apparatus whereby it is possible to safely use a lamp or bulb of high wattage.

Furthermore, it is an object of the invention to provide a fan for position exteriorly of the shell of the projecting machine to draw out from the shell and disperse exteriorly thereof the air heated within the shell or more particularly the lamp housing within the shell.

The invention consists in the details of construction and in the combination and arrangement of the several parts of our improved fan for picture projecting apparatus, whereby certain advantages are attained, as will be hereinafter more fully set forth.

In order that our invention may be better understood, we will now proceed to describe the same with reference to the accompanying drawings, wherein:

Figure 1 is a fragmentary view in section with parts in elevation illustrating a fan embodying the invention in applied position; and

Figure 2 is a fragmentary view in top plan of Figure 1 with a portion broken away.

As illustrated in the accompanying drawings S denotes the shell or outside casing of a picture projecting machine of a general type as used in connection with still or moving pictures. Positioned in the shell or casing S is a lamp H of a conventional type in which is placed the usual light B. The top wall I of the shell or casing s is provided with the louvered vents 2 directly along the lamp housing for the escape of the heated air within the shell or casing S.

The vents l themselves, however, do not allow for the escape of air in sufiicient volume to maintain cooling of the walls 2 of the shell or casing S or to permit the use of a bulb of high wattage. These disadvantages are overcome by drawing out the heated air within the housing in a manner whereby the walls of the shell or housing S are maintained cool and a bulb or lamp of high wattage may be used with safety especially with respect to the film or slides being used.

A relatively short sleeve 3 is positioned on the top wall I of the shell or casing S and surrounding the vents 2. In the present embodiment 2 of the invention the collar 3 is detachably held as at 4 to the top wall 1 so that the same may be applied or removed as desired.

Extending inwardly from the outer or upper end portion of the sleeve 3 are the diametrically opposed arms 5. These arms 5 are substantially in alinement and are secured, as at 6, by screw or the like, to bracket 1 carried by the field ring a of the motor M. These arms 5 not only support the motor M in desired position but provide means to hold the field ring or against rotation.

The shaft 8 of the motor M is upwardly disposed and has fixed to its upper extremity the axial center of the top head 9 of the fan F. This fan F comprises a cylindrical wall [0 depending from the peripheral portion of the head 9 and open at its bottom or lower end. The wall member I0 is substantially housing the motor M.

The cylindrical wall [0 has struck therefrom and extending from substantially one end to the other the blades I l providing air slots [2 between each pair of blades ll. These blades H are equidistantly spaced and are arranged entirely around the wall In. The blades II are also on such pitch to provide means for creating such suction within the shell or housing S to withdraw therefrom and disperse out into the atmosphere the heated air with the shell or casing S and in such volume to assure the maintenance of the shell or casing S substantially free of heat.

At predetermined spaced points therearound the upper or outer end portion of the collar 3, are the outwardly disposed ears l4 to which are secured the upstanding posts l5 which extend upwardly into a dome D and have close contact within the lower free marginal portion of the side wall 16 of the dome D. The wall It; may be secured to the posts Is in any desired manner, as by screws H.

The side wall l6 and the top wall [8 of the dome D is imperforate and the lower or open end of the dome is of a diameter to extend a distance materially outwardly from the collar 3 whereby a discharge opening is provided surrounding the collar 3 and through which is discharged the air after being drawn out from within the shell or casing S.

We claim:

1. In combination, a picture projecting machine including a casing having an exhaust opening through a wall thereof, a sleeve mounted on said wall exteriorly of the casing and surrounding the discharge opening, a downwardly facing hood carried by the sleeve and positioned thereabove, said hood having its lower face open and of a diameter greater than the diameter of the sleeve, a shaft disposed axially of the sleeve and supported thereby, said shaft being of a length to extend a distance within the hood, means for rotating the shaft, a head carried by the outer end portion of the shaft, and a wall extending from the peripheral portion of the head toward the sleeve, said wall having blades struck therefrom and providing openings between adjacent blades.

2. In combination, a picture projecting machine including a casing having an exhaust opening through a wall thereof, a sleeve mounted on said wall exteriorly of the casing and surrounding the discharge opening, a downwardly facing hood carried by the sleeve and positioned thereabove,

said hood having its lower face open and of a diameter greater than the diameter of the sleeve, a shaft disposed axially of the sleeve and supported thereby, said shaft being of a length to extend a distance within the hood, means for rotating the shaft, a head carried by the outer end portion of the shaft, and a wall extending from the peripheral portion of the head toward the sleeve, said wall having blades struck therefrom and providing openings between adjacent blades, said wall being of substantially the same diameter as the sleeve and terminating closely adjacent thereto.

3. In combination, a picture projecting machine including a casing having an exhaust opening through a wall thereof, a sleeve mounted on said wall exteriorly of the casing and surrounding the discharge opening, a hood carried by and concentric with the sleeve, and said hood having a circular open side spaced from and directed toward said wall, said circular open side being of a diameter greater than the diameter of the sleeve, a motor unit having a field ring and an armature therein, means supporting the motor unit in the center of the outer end of the sleeve with the turning axis of the armature concentric with the sleeve, a shaft supporting the armature and having an end extending outwardly into the hood, and a suction fan carried upon the outer end of the shaft within the hood, said suction fan comprising a cylindrical body having a head and a wall extending from the head toward the sleeve, said wall having blades struck therefrom providing openings between the blades, and said motor being encircled by the wall and partially disposed within the fan body.

CLARENCE J. CADWELL.

FRANK M. ADAMSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,409,199 Roth Mar. 14, 1922 1,598,444 Howell Aug. 31, 1926 1,937,379 Berg Nov. 28, 1933 2,027,679 Debrie Jan. 14, 1936 2,027,680 Debrie Jan. 14, 1936 2,126,230 Troxell Aug. 9, 1938 2,153,576 Kurth et al Apr..11, 1939 2,165,681 Stechbart July 11, 1939 2,186,618 Philips Jan. 9, 1940 2,269,794 Stechbart Jan. 18, 1942 2,288,345 DeVry June 30, 1942

Images