US3056581A

US3056581A - Blade attachment

Info

Publication number: US3056581A
Application number: US846426A
Authority: US
Inventors: William S Castle; John B Minnich
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1959-10-14
Filing date: 1959-10-14
Publication date: 1962-10-02
Anticipated expiration: 1979-10-02

Description

1962 w. s. CASTLE ETAL 3,056,581

BLADE ATTACHMENT Filed Oct. 14. 1959 2 Sheets-Sheet l INVENTORJ ATTORNEY 1962 w. s. CASTLE ETAL 3,056,581

BLADE ATTACHMENT Filed Oct. 14, 1959 2 Sheets-Sheet 2 /flfl :2; if ya 1 1/ 17 7/ OHO QWLJL 6/ 52 INVENTORS ATTORNEY ilit hoe

3,056,581 BLADE ATTACHMENT William S. Castle, Speedway, and John B. Minnich, Indianapolis, Ind, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Oct. 14, 1959, Ser. No. 846,426 4 Claims. (Cl. 253-77) This invention relates to a rotor assembly.

More particularly, it is an object of this invention to provide a low cost fabricated rotor assembly that is easy to assemble and disassemble.

Other objects, features and advantages will become apparent upon reference to the succeeding detailed description and to the drawings illustrating the preferred embodiments of the invention, wherein,

FIGURE 1 is a front elevational view with parts broken away and in section of one embodiment of the invention,

Figure 2 is an enlarged cross-sectional view taken on a plane indicated by and viewed in the direction of the arrows 2-2 of FIGURE 1,

FIGURE 3 is a cross-sectional view taken on a plane indicated by and viewed in the direction of arrows 3-3 of FIGURE 2,

FIGURE 4 is an enlarged exploded perspective view of a detail,

FIGURE 5 is a front elevational View with parts broken away and in section of another embodiment of the invention,

FIGURE 6 is an enlarged cross-sectional view taken on a plane indicated by and viewed in the direction of arrows 66 of FIGURE 5, and

FIGURE 7 is a cross-sectional view taken on a plane indicated and viewed in the direction of arrows 77 of FIGURE 6.

Referring to the drawings and more particularly to FIGURE 1, there is shown therein an arcuate portion 10 of an axial flow type rotor assembly 12 incorporating one embodiment of this invention, the assembly including a number of blades 14 adapted to be secured to a wheel 16 and spaced equally circumferentially therearound by a number of spacers 18, the blades, spacers and wheels being secured to each other and to a number of reinforcing and attaching members 20.

Referring more particularly to the details, each of the blades 14 is preferably stamped from sheet metal in the shape of an air foil as shown and having a radial slot 22 provided centrally therein at the reduced radially inner end 24 for receiving the wheel or disk 16 therein. The blades 14 are joined to the wheel 16 by a number of right angle reinforcing bracket members having axially extending leg portions 26 secured to the blades by the insertion of rivets 28 or the like through

suitable holes

30 and 32 provided in each, and circumferentially extending leg portions 34 adapted to be secured to the wheel.

Each of the leg portions 34 is stamped to provide a stepped or tongue portion 36 to permit a circumferential interfit between oppositely positioned adjacent leg portions upon assembly thereof so that both a circumferential and radial stop is provided preventing relative movement between the blades and wheel. A minimum clearance is maintained between the interfitted portions to permit growth upon thermal expansion of the parts. The interfitted portions together therefore constitute a substantially U-shaped reinforcing member between adjacent blades.

Adapted to overlie the adjacent leg portions 34 of the bracket members and completely span the circumferential space between radially inner portions of the blades are the spacer means 18 equally spacing the blades around the periphery of the wheel and also constituting a baflle preventing the flow of gas in an axial direction between blades except as to be described. Each of the spacer means 18 comprises two radially extending

sheet metal plates

38 and 40 each of a width equal to the desired circumferential distance between blades.

Plates

38 and 40 are axially spaced from each other as shown in FIGURE 2 and flanged at their radially outer portions 42 and 44 for cooperation with a top sheet metal plate portion 46 constituting a blade platform over which the gases passing between the blades are directed. Leg

portions

38 and 40 are adapted to overlie adjacent leg portions 34 of the reinforcing bracket members 20 to join them together and to the wheel in a manner to be de scribed to provide a rigid connection therebetween. The spacer leg 38 also provides a streamlined unbroken frontal area against which the gases impinge, thus reducing friction losses, etc. The angle at which the platform is directed with the axis is that providing the most efficient angle of flow of the gas passing between blades.

In the assembly of this embodiment of the invention, the axial leg portions 32 of the reinforcing members 20 are initially riveted to the blades 14 on both sides thereof as shown in FIG. 3. The slotted end 24 of each of the blades is then dropped into position over the wheel 16 with the rivet holes 48 provided in the circumferential leg portions 34 of the brackets being aligned with the holes 50 provided in the wheel, and the oppositely positioned stepped portions 36 of adjacent brackets interfitting as shown in FIGURES 1 and 4 to provide a circumferential and radial stop therebetween. The spacers 18, which have been preassembled by riveting the platform 46 to the leg portions 38 and 40' at 52 and 54, are then positioned in place between the blades and over the bracket legs 34 and wheel 16, with the rivet holes 58 provided in the spacer legs aligned with holes 48 and 50 in the brackets and wheel, and the whole assembly is riveted together. The assembly is thus rigidly connected together with the spacers completely spanning the gap between blades to force the gas passing therebetween to flow over and at the angle of the platform.

FIGURES 5-7 illustrate a different embodiment of the invention wherein the fabricated assembly includes a plurality of circumferentially spaced sheet metal air foils or blades 60 adapted to cooperate with a rotor consisting of two annular axially spaced flat

sheet metal plates

62 and 64. Each of the air foils 60 is formed with a reduced inner radial tang portion 66 recessed or cut back at 68 to form a further reduced section 70 of an axial width to fit tightly between the two

plates

62 and 64, the point of cut back of the tang as shown in FIGURE 6 therefore providing shoulders or steps 72 constituting a stop to radially locate the blade with respect to the wheel.

As in the FIGS. 1-4 construction, each of the blades is secured to the rotor plates by four right angle bracket members 74, two cooperating with each other on each side of the blade to together form a substantially U-shaped member, the brackets having axial leg portions 76' riveted to the blades as shown at 78 and 80 in FIGURE 6 and circumferentially extending leg portions 84 adapted to be secured to the plates.

The spacer means 86 comprise two axially spaced radially extending

leg portions

88 and 90 flanged at their

ends

92 and 94 and riveted at 96 and 98 to a top plate to that of FIG. 1, i.e., the axial leg portions 76 of

bracket members

102 and 104 are riveted to the reduced portion 70 of the airfoil tank at 78 and 80, the tang is then dropped into position between the plates until the shoulders 72 rest on the upper edges of the plates and the rivet holes 106 provided in the circumferential legs 84 align with holes 107 drilled in the plates, the spacers are then positioned against the inside of the brackets with the rivet holes 110 therein aligned with holes 106 and 108, and the entire assembly is then rigidly locked together by riveting of the same as shown.

From the foregoing, it will be seen therefore that this invention provides an easily assembled and disassembled fabricated rotor assembly constructed of sheet metal to provide an economical assembly.

While the invention has been illustrated in its preferred embodiments in FIGS. l-7, it will be clear to those skilled in the art to which this invention pertains that many modifications may be made without departing from the scope of the invention.

We claim:

1. A rotor blade assembly comprising a disk, a plurality of blades adapted to straddle and be secured to said disk at the periphery thereof, spacer means for circumferentially spacing said blades and spanning the gap therebetween, and securing means for securing said blades, spacer means and said disk rigidly together, said means comprising a plurality of substantially right angle reinforcing members each having leg portions secured to one of said blades and other leg portions secured to said disk, said other portions of adjacent members being interfitted with each other to provide circumferential and radial stops for the movement of said blades relative to said disk.

2. A rotor blade assembly comprising a thin disk, a plurality of blades adapted to be secured to said disk at the periphery thereof, spacer means for circumferentially spacing said blades and spanning the gap therebetween, and securing means for securing said blades, spacer means and said disk rigidly together, said means comprising a plurality of substantially right angle reinforcing members each having first leg portions secured to one of said blades and other leg portions secured to said disk, said blades each having a slot therein at one end for straddling the periphery of said disk therein, adjacent leg portions of said members having a stepped construction permitting a circumferential interfit therebetween to circumferentially and radially locate said blades with respect to said disk.

3. A lightweight fabricated rotor assembly comprising a thin sheet metal disk, a plurality of slotted airfoil type blades adapted to straddle the outer periphery of said disk and extend laterally therefrom, spacer means circumferentially spacing said blades, a plurality of bracket members securing each of said blades to said disk, and means to connect said spacer means to mutually adjacent bracket members and said disk to rigidly connect mutually adjacent blades to each other and said disk, adjacent portions of said brackets having radially and circumferentially interlocking parts to align said blades relative to each other and said disk.

4. A lightweight fabricated rotor assembly comprising a thin sheet metal disk, a plurality of slotted airfoil type blades adapted to straddle the outer periphery of said disk and extend laterally therefrom, spacer means between said blades for circumferentially spacing said blades, a plurality of substantially right angle bracket members securing each of said blades to said disk, and means to connect said spacer means to mutually adjacent bracket members and said disk to rigidly connect mutually adjacent blades to each other and said disk, adjacent portions of said brackets having radially and circumferentially interlocking parts to align said blades relative to each other and said disk.

References Cited in the file of this patent UNITED STATES PATENTS 926,442 Smoot June 29, 1909 2,867,407 Stalker June 2, 1959 FOREIGN PATENTS 163,871 Australia July 5, 1955 718,139 Great Britain Nov. I0, 1954