Bearing and seal assembly for turbines

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Drawing sheet — no readable text.

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Drawing sheet — no readable text.

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paid My to 1st 2,469,734

UNITED STATES PATENT OFFICE

BEARNG AND SEAL ASSEMBLY FOR

TURBONES

Walter A. Ledwith, Hartford, Conn, assignor to

United Aircraft. Corporation, East Hartford,

Conn, a corporation of Delaware

Application August 23, 1944, Serial No. 550,888

This invention relates to a bearing and seal with rows of blades 44 on the rotor. Bosses 8 are all on ring 36 so that the supporting pins all assembly for an elastic fluid turbine. engage the same ring. An inlet scroll 46 directs Turbines generally have labyrinth Seals be tween the bearings for the turbine rotor and the the driving fluid through the row of nozzles On power section of the turbine. The seal elements guides thecasing 5 the face ring 34, and an exhaust duct 48 driving fluid from the last row of blades have been separate from the bearing and have been separately mounted on the rotor and in the on the rotor.

housing. A feature of this invention is a com The front bearing and seal are assembled as a pact bearing and seal assembly permitting mount unit. As shown in Fig. 2 the bearing 22, which ing of these elements as a unit in the turbine O may be continuous, engages with a sleeve 50 which structure. . fits over the turbine shaft. Interengaging Splines Another feature is the inclusion in the bearing 52 on the outer end of the sleeve and the shaft and Seal assembly of a thrust bearing which re prevent relative rotation. Sleeve 50 forms a bear sists the axial thrust exerted on the rotor during ing surface for the turbine shaft and has a pro turbine operation. 5 jecting rib 54, one surface of which engages with Another feature is the alignment of the main the end of the bearing 22 and the other surface of bearing and the thrust bearing in a unitary as which engages with a number of bearing shoes Sembly. 56. These shoes are supported by projections on The assembly may include a sleeve fitting on a ring 58 which has a spherical surface 60 en the rotor shaft and providing a bearing surface 20 gaging with a bearing block 62 surrounding the and another sleeve on the shaft having a number sleeve 50. Ring 58 and block 62 may be continu of sealing elements thereon. A feature of this ous. Block 62 and bearing 22 may have inter invention is the use of interengaging face splines engaging face splines 63 to prevent relative ro for holding these sleeves against relative rota tation.

tion and to permit easy assembly of the parts. The bearing 22 and the bearing block 62 are Other objects and advantages will be apparent carried by a supporting sleeve 64 which has a pro from the Specification and claims, and from the jecting rib 66 engaging the block 62 and a shoul accompanying drawings which illustrate an em der 68 which may engage a cooperating shoulder bodiment of the invention. 70 on bearing 22. Sleeve 64 is split longitu Fig. 1 is a sectional view through the turbine. 30 dinally to permit assembly over the bearings and Fig. 2 is a fragmentary sectional view on a bearing block.

larger scale of the front bearing and Seal as The sleeve 64 has integral therewith the outer Sembly. element 72 of the labyrinth seal which is located The turbine includes a casing 0 and rotor 2 between the bearing and the power Section of the both supported in a housing 4. The casing is 35 turbine. This outer element is in the form of a supported by radially extending pins 6 carried by sleeve which is spaced from an inner sleeve 74 the housing and engaging bores in bosses 8 on mounted on the turbine shaft. The sleeve 74 is the casing. These pins are all in Substantially the held against a shoulder 76 on the shaft and is same plane and constitute the Sole Support for caused to rotate with the shaft by interengaging the casing so that the casing is free to expand 40 face splines 78 on the end of sleeve 74 and the lengthwise. In the plane of the pins the Casing bearing sleeve 50. Sleeves 74 and 50 are held in is smaller than the housing and clearance is pro position on the shaft by a ring 80 threaded in the vided at the inner ends of pins 6 to permit the end of the shaft and clamping a collar 82 against casing to expand radially. the end of sleeve 50.

Housing 4 has a head 20 which forms a part 45 of the housing and supports a bearing 22 for the Sleeve 4 has a number of spaced outwardly extending sealing elements 84 cooperating With front end of the turbirce shaft 24 forming an in ribs 85 on the inner surface of the sleeve 72 to pre tegral part of the rotor. At the other end of the Went ieakage of power fuid from the power Sec housing a spider 26 supports a bearing 28 for tion of the turbine. Sleeve 74 also may have an the turbine shaft. The spider has a number of 50 integral oil slinger ring or flange 86 located ad legs 30 engaging radially positioned pins 32 car jacent to bearing block 62 to prevent the flow of ried by the housing. oil along the surface of sleeve 74 and into the Casing O is built up of several rings 34, 36, 38 seal. It may be noted that sleeve 4 is spaced and 40, each of which has a single row of nozzle forming guides 42. These rows of guides alternate from the turbine shaft except at its outer end,

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thereby to limit the transfer of heat directly from bearing, said support having means cooperating the rotor to said sleeve. with the sealing elements on said second sleeve. A flexible seal 88 extends from an outwardly. 5. A bearing and seal assembly for a turbine projecting rib 90 on the outer seal element 72 to having a rotor and a surrounding housing, said the inner periphery of the first stage nozzle ring assembly including a sleeve adapted to be mount 34 to prevent leakage of power fluid. The ele ed on the rotor shaft and having a projecting ment 72 may also have a laterally projecting flange, another sleeve forming an extension of flange 92 fitting in and guided by a sleeve 9 said first sleeve and having a number of seal forming an integral part of the head 20 of hous ing elements thereon, a bearing engaging said ing 4. In assembly, the bearing 22 together with .0 first sleeve, a thrust bearing engaging said bearing blocks 56, ring 58 and block 62 are flange, and a support for said bearing and said mounted on sleeve 50, and sleeve T4 is placed in thrust bearing, said support having means co alignment with sleeve 50. The outer supporting operating with the sealing elements on said sec sleeve 64, which, as above stated, is split longi ond sleeve, said support being adapted to be tudinally, is then placed over the remaining parts positioned axially within said housing. of the assembly and the entire assembly may s 6. A bearing and seal. assembly for a turbine then be mounted as a unit in a cylindrical recess having a rotor and a surrounding housing, said in the head 20 or on the turbine shaft. The as assembly including a sleeve adapted to be mount sembly may be locked in position in head 20 by ed on the rotor shaft and having a projecting bolts 96 which extend through a part of the head 20 flange, another sleeve forming an extension of and into the supporting sleeve 64. said first sleeve and having a number of seal It is to be understood that the invention is not ing elements thereon, a bearing engaging said limited to the specific embodiment herein illus first sleeve, a thrust bearing engaging said flange, trated and described, but may be used in other and a Support for said bearing and said thrust ways without departure from its spirit as defined 25 bearing, said support having means cooperating by the following claims. - with the sealing elements on said second sleeve, I claim: - Said Support being adapted to be positioned 1. A bearing assembly for supporting a turbine axially within said housing, and means for se rotor in a housing including a sleeve adapted to curing Said Support within said housing. be mounted on the rotor shaft, said sleeve have 30 7. A bearing and seal assembly including a ro ing a substantially cylindrical bearing surface. tating shaft, a sleeve mounted on the shaft, and a projecting flange, a main bearing Sur means on said shaft for limiting the axial move rounding the bearing surface on said sleeve, a ment of the sleeve in one direction, said sleeve stationary bearing Support for said bearing having a number of axially spaced outwardly adapted to be mounted in the turbine housing, 35. extending radial sealing elements thereon, a sec and a thrust bearing ring carried by said sta ond sleeve adapted to be mounted on said shaft tionary support and carrying shoes engaging one in endwise engagement with the first sleeve, said side of said flange, all of Said parts being con Second sleeve having a bearing surface, a con tinuous annular elements except for the station tinuous annular bearing around the bearing sur ary bearing Support and the Shoes, t face on said second sleeve, a stationary support 2. A bearing and seal assembly including a for said bearing, said support having an integral sleeve adapted to be positioned on a rotating substantially cylindrical extension with axially shaft, said sleeve having a number of sealing ele spaced inwardly extending radial sealing elements ments thereon, another sleeve adapted to be cooperating with the sealing elements on said mounted on said shaft and having a bearing Sur first sleeve, said support being split for assembly face, a bearing around said second sleeve, and Over the sealing elements on the sleeve, and a support for said bearing, said support having means for clamping said second sleeve axially an integral extension with sealing elements co against said first sleeve , and said first sleeve operating with the sealing elements on said first against Said means on Said Shaft. sleeve, in combination with a thrust bearing Sup 50 8. A bearing and seal, assembly including a ported against axial movement by Said Support rotating shaft, a sleeve mounted on the shaft, said another sleeve having means thereon engag means on said shaft for limiting the axial move ing axially with said thrust bearing. ment of the sleeve in one direction, said sleeve 3. A bearing and seal assembly including a having a number of axially spaced outwardly ex sleeve adapted to be positioned on a rotating 55 tending radial sealing elements thereon, a second shaft, said sleeve having a number of sealing ele sleeve adapted to be mounted on said shaft in ments thereon, another sleeve adapted to be endwise engagement with the first sleeve, said mounted on said shaft and having a bearing sur Second sleeve having a bearing surface, a con face, a bearing around said second sleeve, and a tinuous annular bearing around the bearing sur support for said bearing, said support having an face on said Second sleeve, a stationary support integral extension with sealing elements Coop for said bearing, said support having an inte erating with the sealing elements on Said first gral substantially cylindrical extension with ax sleeve, in combination with a thrust bearing Sup ially spaced inwardly extending radial sealing ported against axial movement by said support, 05 elements cooperating with the sealing elements said second sleeve having a projecting flange with on said first sleeve, in combination with means which the thrust bearing engages. for clamping both of said sleeves on the shaft 4. A bearing and seal assembly for a turbine and for holding said first sleeve against said having a rotor and a surrounding housing, said means on said shaft.

assembly including a sleeve adapted to be 9. A bearing and seal assembly including a ro mounted on the rotor shaft and having a pro tating shaft, a sleeve mounted on the shaft, jecting flange, another sleeve forming an exten means on said shaft for limiting the axial move sion of said first sleeve and having a number of ment of the sleeve in One direction, said sleeve sealing elements thereon, a bearing engaging said having a number of axially spaced outwardly ex first sleeve, a thrust bearing engaging said flange, tending radial sealing elements thereon, a sec and a support for said bearing and said thrust Ond sleeve adapted to be mounted on said shaft

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tinuous annular bearing around the bearing sur in endwise engagement with the first sleeve, said face on said second sleeve, a stationary support second sleeve having a bearing surface, a con for said bearing, said support having an integral tinuous annular bearing around the bearing sur Substantially cylindrical extension with axially face on said second sleeve, a stationary support Spaced inwardly extending radial sealing ele for said bearing, said support having an integral ments cooperating with the sealing elements on substantially cylindrical extension with axially said first sleeve, said sleeve having interengaging spaced inwardly extending radial sealing ele face splines to prevent relative rotation, and one ments cooperating with the sealing elements of said sleeves being splined to the shaft, said on said first sleeve, said support being split 3. Support being split for assembly over the sealing for assembly over the sealing elements on the io elements on the sleeve, and means for clamping sleeve, and means for clamping said second Said second sleeve axially against said first sleeve sleeve axially against said first sleeve and said and said first sleeve against said means on said first sleeve against said means on said shaft, shaft.

said first sleeve being spaced from the shaft ex WALTER A. LEDWITH. cept at the end adjacent to said second sleeve, and said limiting means on said shaft being located REFERENCES CTED adjacent to the end of the first sleeve adjacent to The following references are of record in the said Second sleeve. file of this patent:

10. A bearing and seal assembly including a rotating shaft, a sleeve mounted on the shaft, UNITED STATES PATENTS means on said shaft for limiting the axial move ment of the sleeve in one direction, said sleeve N. 1,158,424

Name

Date

having a number of axially spaced outwardly 1762,117 Dahlstrand --------- June 3, 1930 extending radial sealing elements thereon, a Sec 23 1,918,988 Searles et al. -------- July 18, 1933 ond sleeve adapted to be mounted on said shaft 1,971,547 . White-------------- Aug. 28, 1934 in endwise engagement with the first sleeve, said 2,040,218 Soderberg ---------- May 12, 1936 Second sleeve having a bearing surface, a con v