US3038652A - Intermediate compressor case - Google Patents

Description

June 12, 1962 A. E. SHEPARD 3,038,652

INTERMEDIATE COMPRESSOR CASE Filed Oct. 2l, 1959 2 Sheets-Sheet 1 FEGJ INVENTOR Amos a- SHEPARD BY ATTORNEY June 12, w62 A. E. SHEPARD INTERMEDIATE COMPRESSOR CASE 2 Sheets-Sheet 2 Filed oct. 21, 1959 FIG-2 F' l C5 3 F' I G L m @v /MN TH R NS O Wv E T m A AMO S United States Patent 3,038,652 INTERMEDIATE COMPRESSOR CASE Amos E. Shepard, Glastonbury, Conn., assigner to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Filed Oct. 21, 1959, Ser. No. 847,803 4 Claims. (Cl. 230-120) This invention relates to a compressor bearing support and particularly to the supporting structure by which the compressor rotor or rotors are held concentric to the surrounding casing.

One feature of the invention is an arrangement for supporting the thrust bearings within the compressor casing so as to reduce the stresses in the supporting structure. In this Way the bearings will be held in position and relative axial movement between the casing and rotor will be minimized.

Another feature of the invention is an arrangement of the supporting vanes within the intermediate casing in such a way as to re-enforce the bearing carrying structure.

One particular feature of the invention is an arrangement of this character adapted for use between the lowpressure compressor and the high-pressure compressor of a split engine. One engine of this type is described in the Savin Patent No. 2,747,367.

'Other features and advantages will appear from the following detailed description.

FIG. l is a longitudinal sectional view through the intermediate casing or housing.

FIG. 2 is a fragmentary sectional View along the line 2-2 of FIG. l.

FIG. 3 is a View in elevation of one of the supporting vanes.

FIG. 4 is a fragmentary sectional view along the line 4 4 of FIG. l.

The invention is shown in the intermediate housing for a split engine of the type described in the aboveidentified Savin patent. In this type of power plant a low-pressure compressor is positioned at the left of the intermediate housing shown in FIG. 1 and this 10W- pressure compressor has a rotor including a shaft 2 which is supported within the housing 4 on thrust bearings 6. The rotor has a row of blades 7 on its periphery -in axially spaced relation to a row of stator vanes 8 carried by the surrounding casing 9, a portion only of which is shown. This casing forms the outer wall of the gas path 10. The inner wall of the gas path is defined by a sleeve 12 supported by the housing as will be described.

To the right of the housing 4 is the high-pressure compressor which has a casing 13 attached to the sleeve 14. The high-pressure rotor 16 -is supported in concentric relation to the shaft 2 of the low-pressure-rotor by the intershaft bearing 18.

The intermediate housing 4 Iincludes a substantially conical member or cone 20, the inner edge of which has an integral cylinder 22 within which the bearings 6 are positioned. The outer periphery of the cone 20 engages with an inner shroud ring 24. Also forming part of the housing -is another disk 26 spaced axially downstream from the cone 20 and attached as by bolts 28 to an inwardly extending ange 30 on the inner shroud 24. The cone 20 and disk 26 are held in spaced relation to each other adjacent their inner edges by a sleeve 32 having flanges at opposite ends by which the sleeve is attached as by bolts 34 to the cone 20 and by bolts 36 to the disk 26. Thus the cone 20, the disk 26 and sleeve 32 form, in conjunction with the inner shroud 24, a substantially rigid structure which serves "l ce 3,38,652 Patented June 12, 1962 to hold the bearings 6 in predetermined axial position with respect to the inner shroud.

The inner shroud ring 24 is connected to and held in xed relation to an outer shroud ring 38 by a plurality of stator vanes 40 extending across the gas path and rigidly secured in each of the shroud rings. Eachshroud ring is provided With circumferentially spaced openings which receive the ends of the vanes. As shown in FIGS. 2 and 4, the inner shroud ring 24 has circumferentially spaced openings 42 in which the inner shroud elements 44 integral with the vanes 40 are received and the outer shroud ring 38 has the openings 46 which receive the outer shroud elements 48 integral with the vanes. The vanes are kwelded securely within the respective shrouds to form in effect an integral unit.

Each vane has a tongue 50 extending inwardly from the inner shroud element 44 and this tongue extends at the same angle to the axis of the shaft as does any element of the cone 20. The latter `has peripheral notches 52 to receive the tongues 50 and the tongues are thick enough so that when positioned in the notches, the opposite surfaces of the tongues extend axially beyond the opposite surfaces of the cone. The cone and tongues and inner shroud are then welded together into an integral unit.

The outer shroud ring 38 has axially spaced projecting llanges 54 and 56 by which the outer shroud ring is connected to the low-pressure compressor casing 9 and to the sleeves 14, bolted in turn to the high-pressure compressor casing 13. The cone 20 is preferably positioned at such an angle that an element of the cone, if extended, would intersect or substantially intersect with flange 56. The flange, as shown, extends substantially at the same angle as the cone.

In order that the shroud rings 24 and 38 may be as thin as possible and still provide the necessary support, each of the vanes 40 carries, in addition to the tongue 50, projecting feet 58, 60 and 62 which project into and are received in notches in the flanges 54, 56 and 64, respectively. Thus, as shown in FIG. 4, the foot 5S fits within a notch 66 in the flange 54 and is suitably secured therein. The anges are preferably formed as rings and then welded to the respective shroud rings.

It will be understood that, in order to maintain the axial position of the rows of blades and vanes in the low and high pressure compressors, it is essential that there be a minimum of axial movement between the rotor and the surrounding casing. This relative axial movement is minimized by the intermediate housing above described. The intermediate housing also must be extremely rigid in order to eifectively support the accessory drive shown in FIG. l so that there will be no misalignment between the bevel gear 68 on the rotor 16 and the accessory, not shown, mounted externally of the casing. The bevel gear 68 `is in driving engagement with a cooperating gear 70 having an integral sleeve 72 supported by bearings 74 within a 'cylinder 76 positioned in and supported by the sleeve 32. 'Ihe sleeve 72 is connected by a driving ring 78 to the accessory drive shaft 80 lwhich extends through one of the vanes 40. The drive shaft extends into the accessory housing not shown and is journalled therein. Accordingly, it is essential for the accessory drive that the intermediate housing be rigid.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described but may be used in other ways without departure from its spirit as defined by the following claims.

I claim:

1. In an axial ow compressor, a casing, a rotor including a shaft within the casing, a housing connected to and extending inwardly from the casing to said shaft, a bearing supporting said shaft and carried by said housing, said housing including an outer shroud ring, an inner shroud ring, said shroud rings being disposed in spaced concentric relation and each having a series of circumferentially spaced openings therethrough, a row of stator vanes, each vane having inner and outer shroud elements received within and welded in said openings in the inner and outer shroud rings, respectively and a conical supporting member extending outwardly from said bearing and engaging said inner shroud ring, said outer shroud ring including projecting attachment flanges at opposite axial edges, the ends of said shroud elements having radially projecting feet, and said flanges having notches to receive said feet.

2. An axial ow compressor as dened in claim 1 in which said housing also includes a cylindrical member attached to and extending from said conical member and surrounding the shaft and a disc attached to said cylindrical member in spaced relation to the conical member, said disc extending outwardly from the cylindrical member, and means, including a ange carried by said inner shroud ring, means securing the outer edge of said disc with said inner shroud ring, said inner shroud ring flange including notches to receive the feet on said stator vanes.

3. In an axial flow compressor, a casing, a first row of stator vanes carried by said casing, a rotor within the casing supporting a row of blades adjacent to said first row of stator vanes, said rotor including a shaft, and a housing disposed within and attached to said casing, said housing having bearings supporting said shaft, said housing including another row of stator vanes axially spaced from said lirst row of stator vanes, an inner shroud ring, said inner and outer shroud rings being disposed `in spaced concentric relation and eaoh having a senes of circumferentially spaced openings therethrough, each of said other row of stator vanes having inner and outer shroud elements received within and welded in said openings in said inner and outer shroud rings, respectively, a conical support member attached to and extending inwardly from said inner shroud ring to said bearings, a disc axially spaced from said conical member, a sleeve connecting said conical member and disc adjacent their radial inner edges, and flange means, carried by opposite axial edges of said inner shroud ring, means securing said flange means to the radially outer edge of said disc, said other row of vanes including radially projecting feet at the upstream and downstream ends, and said ilange means having notches to receive said feet.

4. An axial tlow compressor as dened in 'claim 3, in which said outer shroud ring includes axially spaced attachment flanges at the opposite edges thereof, one of said axially spaced attachment anges including a portion extending substantially at the same angle as the conical support member and a portion extending radially outward from said angularly extending portion, and in which elements of the conical member, extended, would pass substantially through said attachment flange having the angularly extending portion.

References Cited in the iile of this patent UNITED STATES PATENTS 843,237 Shepherd Feb. 5, 1907 2,143,467 Allard Ian. 10, 1939 2,696,711 Marchant et al. Dec. 14, 1954 2,747,367 Savin May 29, 1956 2,851,246 Nichols Sept. 9, 1958 2,869,820 Marchant et al. Ian. 20, 1959 2,910,269 Haworth et al. Oct. 27, 1959 2,932,443 Gunberg et al. Apr. 12, 1960 2,937,000 Ledwith May 17, 1960 FOREIGN PATENTS 436,882 Italy June 16, 1948 491,575 Canada Mar. 24, 1953

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