US2129808A - Blower - Google Patents

Description

-"Sept.-.-;]/3, 193s. o. D. H. BENTL EY 2,129,808

BLOWER Filed Nov. 9, 1937 4 2 Sheets-Sheet l Sept. 13, 1938. o. D. H. BENTLEY BLOWER 2 Sheets-Sheet 2 Filed NOV. 9, 1937 v 1170877367 OLIVER D. H. BENTLEY by @6012 a Patented Sept. 13, 1938 UNITED STATES PATENT OFFICE .Oliver D. H. Bentley, Norfolk, Mass. Application November 9, 1937, Serial No. 173,637

4 Claims.

This invention relates to blowers and relates more particularly to a combined propeller and centrifugal blower. V

For some classes of work such for example, as providing air for forced draft for naval vessels, air pressureslof the order of 16" of water are required. In order to provide such pressures in the past, it has been the practice to rotate the blower blades at such high speeds that they were not only very noisy in operation but the strains to which they were subjected were great.

According to this invention, a propeller type fan rotating in one direction at a reduced speed, feeds air axially into'the inlet of the wheel, rotating in the opposite direction at a reduced speed, of a centrifugal fan. This results in energy conversion at high efliciency and provides the desired air pressure at greatly reduced speed.

In one embodiment of the invention, a propeller type fan is mounted in the inlet of a centrifugal fan. Oppositely revolving rotors of a steam turbine drive the propeller blades and the fan wheel through concentric shafts. The high relative speeds of the turbine rotors result in an eflicient prime mover, while providing the reduced speed desired for the fan rotors. The propeller blades act to super-charge the centrifugal fan, the air from which is discharged through a preferred involute casing.

An object of the invention is to provide relatively high air pressures by means of relatively low speed blowers.

Another object of the invention is to supercharge a centrifugal fan with a propeller fan.

Another object of the invention is to supercharge a centrifugal fan with a propeller rotating in a direction opposite to that of the fan wheel.

Another object of the invention is to rotate a propeller fan located in the inlet of a centrifugal fan from one rotor of a prime mover while rotating' the fan wheel of the centrifugal fan from another rotor of the prime mover, revolving in a direction opposite to that of the first mentioned rotor.

Other objects of the invention will be apparent from the following description taken together with the drawings.

The invention will now be described with reference to the drawings, of which:

Fig. l is a side elevation of one embodiment of this invention; v

Fig. 2 is a sectional view along the lines 2--2 of Fig. 3;

Fig. 3 is an enlarged cross section of Fig. 1, and

Fig. 4 is an enlarged section along the lines 4-4 of Fig. 3.

The propeller blades In on the hub II are mounted in the inlet passage 92 upon the solid shaft l3. blades I5 is mounted upon the hollow shaft IS. The solid shaft l3 revolves within the hollow shaft H5. The hollow shaft I6 is attached to the rotor i8 of the steam turbine indicated generally by Hi, and the solid shaft i3 is attached to the m rotor of the turbine. The wheel M and rotor l8 rotate around the ball bearings ll which are supported by the vertical extension 30 of the casing 28 of the turbine l9. The details of the turbine rotors and their cooperating mechanism 15 are similar to those disclosed in my Patent No. 1,434,672, issued Nov. 7, 1922, and will not be described in detail here.

In the embodiment of the invention illustrated by the drawings, the upper end of the shaft I3 is supported by the thrust bearing 2| which is enclosed in and supported by the stream-lined hub 22. The hub 22 is supported from the wall 23 by means of the arms 24.

Thecasing 25 of the centrifugal fan is supg ported from the wall 23 as by the bolts 26 in the horizontal extension 21. The casing 28 of the turbine 69 is supported from the lower portion of the casing 25 by means of the bolts 29.

To prevent the passage of steam from the 30 turbine it between the inner shaft l3 and the outer shaft IS, the shaft l3 has attached to it just above the uppermost bearing H, the member 30 which forms a basin containing the mercury 3|. Attached .to the upper portion of the 5 high turbine efilciency. The rotor l8 revolves the 4;,

shaft l6 and centrifugal fan wheel in one direction while the rotor 20 revolves the shaft l3 and the propeller blades ill in the opposite direction. The propeller blades ill deliver a high velocity, whirling air stream, axially into the inlet of the centrifugal fan wheel M. The blades I5 of the wheel l4 revolving in opposite direction to that of the whirling air stream delivered by the propeller blades l0, impact it at high relative velocity providing high energy conversion and a The centrifugal fan wheel M with relatively high air pressure. The air under high pressure is delivered at the outlet ll of the involute casing 25 to be used as desired.

The inlet passage I2 need not, of course, be an opening in a wall as in the embodiment illustrated. The passage may be provided by a casing as is usual in the art. Likewise the centrifugal fan blades may'be curved instead of radial as shown, and other departures may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

1. A blower assembly comprising in combination, a centrifugal fan wheel, means forming an axial air inlet passage into the eye of said wheel, propeller blades'in said passage, a steam turbine having rotors adapted to turn in opposite directions, means connecting one of said rotors with said propeller blades, and means connecting the other of said rotors with said wheel.

2. A blower assembly comprising in combination, a centrifugal fan wheel, a fan casing for collecting and discharging the air from said.

wheel, means forming an axial ,air inlet passage into the eye of said wheel, propeller blades in said passage, a pair of concentric shafts, means for supporting said wheel on one of said shafts, means for supporting said blades upon the other of said shafts, a steam turbine having rotors adapted to turn in opposite directions, means for attaching one of said rotors to one of said shafts, and means for attaching the other of said rotors to the other of said shafts.

,amasoa 3. A blower assembly comprising in combination, a centrifugal fan wheel, a fan casing for collecting and discharging the air from said wheel, means forming an axial air inlet passage into the eye of said wheel, propeller blades in said passage, a pair of concentric shafts, means for supporting said wheel on one of said shafts, means for supporting said blades upon the other of said shafts, a steam turbine having rotors adapted to turn in opposite directions, means for attaching one of said rotors to one of said shafts, meansfor attaching the other of said rotors to the other of said shafts, a turbine casing enclosing said rotors, and means for supporting said turbine casing from said fan casing.

4. A blower assembly comprising in combination, a centrifugal fan wheel, a fan casing for collecting and discharging .the air from said wheel, means forming an axial air inlet e intothe eye of said wheel, propeller blades in said passage, a pair of concentric shafts, means for supporting said wheel on the outer of said shafts, means for supporting said blades upon the inner of said shafts, a steam turbine having rotors adapted to turn in opposite directions, means for attaching one of said rotors to one of said shafts, means for attaching the other of said rotors to the other of said shafts, and means forming a mercury seal between said wheel and the inner of said shafts.

/ OLIVER D. H. BENTLEY.

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