US1050419A - Centrifugal compressor. - Google Patents

Description

0I BANNER.

TRIFUGAL COMPRESSOR. lIPPLILATION FILED IIAR. 21, 191m Patented Jan. I4, 1913.

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w/msssfs iTan sTaTTs raTieNT @FFME OTTO BANNER, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RAND GOM- PNY, OF NEW YORK, N. Y., A CORPORATION 0F NEW JERSEY.

CENTRIEUGAL COMPRESSOR.

Lasarte.

Specification of Letters Patent.

Patented Jan. 1.4L, 1913.

Application led March 21, 1912. Serial No. $85,226.l

To all whom t may concern.'

Be it known that l, Orro BANNER, subject of the German Emperor, residing at Easton, in the State of Pennsylvania, have invented certain new and useful Improyements in Centrifugal Compressors, of which the following is a specification. p

This invention relates to multi-stage centriifugal turbo compressors for air and similar fluids, and more particularly to the design of the blades, and the radial distance ot the inner ends of the blades in the impellers of such machines.

The machines at present used are made up of a series of impellers, the blades of which are all set at approximately the same angle on the impeller disks. A. constant ratio between the radial distance of the inner ends of the blades ot the mpellers and their radii is likewise generally. maintained. ln the construction of these machines great didiculty is experienced in the impellers in the high pressure stages, particularly in machines of small capacity. In order to provide for the decrease involume of the air from impeller to impeller or from stage to stage, it is necessary to decrease the blade width and hence the area of the peripheral orifice of the impeller. Another Way of decreasing this area, and at the same time the force impelling the air outward, is to decrease the diameter of the impellers. In practice both of these methods are resorted to, but in the higher stages of a compressor of low capacity it becomes almost impossible to construct the impellers with a small enough peripheral orifice to get the proper decrease in the volume of the air and hence the eiciency. s

The object of my invention is to so design the blades of the impellers that it is possible to maintain the impeller orifice of a Width which can be constructed without diculty and yet at the same t-ime to attain a high degree of eciency in the impeller.

With this object in view, l increase the angle or" the impeller blades and at the same time decrease the ratio of the radial distance of the inner ends of the blades to the radius of the impeller, from stage to stage or inthe last stage or stages. The advantage obtained thereby is an increase in the ease and consequently a decrease in the cost of Figure-.l is a side elevation partly in section of the complete compressor. Fig. 2 is a diagrammatic showing of the position of l the blades in the impeller in the first stage. Fig. 3 is a section on larger scale through the iinpeller shown in Fig. 2. Fig. lis a diagrammatic showing of the position of the blades .in the impeller in the last stage, and Fig. 5 is a section on a larger scale through the impeller shown in Fig. 4.

"The compressor comprises a horizontally divided casing made up of a lower casing or base 1, and anupper casing 2. In bearings 3, 4, on the base is journaled the shaft 5, on which are mounted a plurality of inipellers of the same diameter which consist of disks G, 7, 8. 9, blades 10, 11, 12, 13, and covers 14, 15, 16, 17. The impellers ...re con nected by air passages 18, 19, 20, which are provided with the usual guide varies, and the air enters the compressor by the inlet chamber 21, which is supplied by any convenient opening, in this case through the base 1, and is taken out through exhaust chamber 22 and exhaust pipe 23.

The usual water jacket 2-1 is provided.

ln the first impeller the blades 10 have a comparatively small angle of inclination, and the air leaves the impeller with comparative ease. In the last stage, the blades 13 have a large exit angle and approach much more nearly to a tangential position at their outer ends, thus retardin the air to a considerable extent and causin it to pass `through the impeller with considerable less velocity than in the first wheel. The angles of the blades of the intermediate impellers in the present compressor may be either graduations between the `first and last, or in one or more impellers may be the same as the nearer end impeller.

Another feature of the present device is that in the impellers the inner ends of blades 11 are nearer the shaft center than the inner ends of blades 10 and likewise the inner ends of blades 12 and 13 are successively nearer the shaft center. This feature contributes to the eciency of the machine Y:lor the impellers in a multi-stage turbo compressor to he built with a higher degree olf" eti'ioiency and with greater ease of construction than has heretofore been known.

lt is to be understood that the present showing only discloses one embodiment oit my intention.

lily invention contemplates using the principles herein disclosed and claimed, in compressors ot a less or greater number ot impellers Whether in groups olf the same design and dimensions and changing from group to group, or changing -irons. impeller to impeller, orl changing :trom group to single impeller, or in any Way consonant with the principles herein set torth. F urthermore, although my invention is particularly adapted to compressors ci small capacity and high pressure, yet it is equally applicable in any compressor where it is desirable to lieep the impellers ci substantially the saine dimensions Without loss or eciency.

lt is to be understood that a slight variation in the angle ot the blades Twill have no appreciable eitect and that therermnst be a material diderence in the eirit angle in the last impeller or impellers to accomplish the desired resnlta u mWhat l claim is: l

l, compressor, a plurality oit inipellers, the tlnirl to compressed i impellers ries ein che last, and :lor said neonazis pellers, the blades in the tiret inipeller hayn ing smaller enit angles than the blades ol the last impeller..

'2. in a compressor, a plurality olf inipellers, the tluid to be compressed passing through said impellers in series from the lirst to the last, and blades t'or said impellers, the blades in one ot said impellers having smaller enit angles than the blades ot the impeller succeeding it,

3. ln a compressor, a plurality ol irnpellers, the fluid to loe compressed passing through said impellers in series trom the lirst to the last, and blades lior said im pellers, the blades in successive iinpellers harincfsuocessively greater enit angles.

el. ln a compressor, a plurality ot' impellers ot' substantially the same diameter, the fluid to be compressed passins through said impcllers in series from the rst to the last, and blades for said impellers, the blades ot the tiret impeller having smaller enit angles than the blades of the last impeller.

5. ln a compressor, a plurality oit iinpellers, the tluid to be compressed passing through said impellers in series iti-om the lirst to the last, and blades tor said impellers, the blades ot the rst impeller haying smaller crit angles than the blades ci the last im. ellers and the ratio ot the radial distance o" the inner ends of the blades oi the iirst impeller to the radius et said impeller being greater than the corresponding ratio in the last impeller.

8., ln a compressor, a plurality oit inipellers, the fluid to be compressed passing in series therethrough, and blades tor said impellers, the ratio oi the radial distance ot the inner ends ot the blades irom the shalt center, to the radius o'll the impellei 'being less in the drst impeller than in the 'Witnesses z Lewis @l @non Lannesrnoit.

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