US3151417A

US3151417A - Throwing wheel vane

Info

Publication number: US3151417A
Application number: US222273A
Authority: US
Inventors: Edward L Hartman; Ralph W Moore
Original assignee: Pangborn Corp
Current assignee: Kennecott Corp; Pangborn Corp
Priority date: 1962-09-10
Filing date: 1962-09-10
Publication date: 1964-10-06
Anticipated expiration: 1981-10-06

Description

Oct. 6, 1964 E. HARTMAN ETAL 3,151,417

THROWING WHEEL VANE 6 Sheets-Sheet 1 Filed Sept. 10, 1962 INVENTORS Edward L.

flarimn fay/z 11010078 ATTOR Oct. 6, 1964 E. HARTMAN ETAL 3,151,417

THROWING WHEEL VANE Filed Sept. 10, 1962 6 Sheets-Sheet 2 INVENTORS EdwwrdLHwrZ mm RaQJh 74?][00 7"6 ATTORNEYS 1964 E. HARTMAN ETAL 3,

THROWING WHEEL VANE 6 Sheets-Sheet 3 Filed Sept. 10, 1962 w x Q w Aw g. 1---- INVENTORS lf'dwwrd/Lflarimrz 1964 E. L. HARTMAN ETAL 3,151,417

THROWING WHEEL VANE 6 Sheets-Sheet 4 Filed Sept. 10, 1962 Z'dwccrcZLHw/"tmwm h more Oct. 6, 1964 E. 1.. HARTMAN ETAL 7 THROWING WHEEL VANE INVENTORS m ,K I 2/ F/ w Filed Sept. 10, 1962 Fdwwrdlffartmn fiavk Wffoo V6 M ATTORNEYS Oct. 6, 1964 E. L. HARTMAN ETAL 7 THROWING WHEEL VANE Fi led Sept. 10, 1962 6 Sheets-Sheet 6 INVENTORS W'jfoore M fidwardLHarZmma United States Patent 3,151,417 THRGWING WHEEL VANE Edward L. Hartman and Ralph W. Moore, Hagerstown, Md, assignors to Pangborn Corporation, Hagerstown, Md, a corporation of Maryland Filed Sept. 10, 1962, Ser. No. 222,273 8 Claims. (Cl. 51-9) The present invention relates to throwing wheels used to project streams of particles against work pieces to subject the work pieces to cleaning, abrading or peening action or the like. A typical wheel of this kind is shown in US. Patent 2,869,289 granted January 20, 1959.

Among the objects of the present invention is the provision of improved vanes for the above wheels.

The above objects and further objects of this invention will be more completely understood from the following description of several of its exemplifications, and the accompanying drawings wherein:

FIG. 1 is a vertical section of a throwing wheel assembly having vanes exemplifying the present invention;

FIG. 2 is a front view of the wheel itself showing some of its throwing vanes in place, and some removed;

FIGS. 3 and 4 are detail sectional views taken of the above wheel along lines 3-3 and 4-4 respectively;

FIG. 5 is a view of one of the vanes in the above wheel, taken from its outer end; a

FIG. 6 is a view of the vane of FIGS. 1-6 taken from its inner end;

FIG. 7 is a front view of the vane of FIGS. 1-6;

FIG. 8 is a view of the vane of FIGS. 1-7, looking from below;

FIGS. 9 through 15 are views corresponding to FIGS. 2 through 8, of a modified vane construction representative of the present invention; and

FIGS. 16 through 25 illustrate various types of locking pins as well as the vane construction and runner heads used therewith.

In use, vanes for the above type of throwing wheels gradually wear away, particularly when they are used to project particles that are very hard, such as steel. The movement of the particles along the length of the vane as they are propelled causes them to abrade and erode these vane surfaces. In some very heavy usages as when sand or alumina contaminate the particles, the vanes might have to be replaced after only about twenty hours of operation or less.

"Abrasion also takes'place with rapid wear at'the ends of the vane. At the exit end, for example, some projected particles generally ricochet back from the work pieces or surrounding members and strike the vane ends causing them to erode faster than other vane portions. In the interest of economy each vane is made of one piece cast into its final shape as closely as possible. If grinding is needed to dress the shape to the final specification, the ground surfaces seem to erode away much more rapidly than the remaining surfaces, and also seem to cause premature breakage. The grinding of the very hard material from which the vane is cast, develops fine cracks which may explain these eifects.

According to the present invention, throwing wheel vanes of improved wear-resistance have a channel-shaped body and an integral mounting flange formed along one or both side edges of the body for engagement in a mounting slot of a wheel, or a recess, the vane being free of ground surfaces and the vane being free of casting gates.

The vane preferably is of abrasion-resistant heat treated steel containing:

(The balance iron.)

These alloys respond particularly well to heat treatment when their thickness is restricted to a maximum of /8 inch. Thick vanes, throughout complete life tests, lost weight approximately 20% faster than thin vanes and develop deeper wear face pockets which destroy efiiciency. Thick vanes weigh approximately 50% more than thin vanes which increases initial cost and imposes heavier operating stresses on support head and attachments.

The heat treatment for the thin vanes consists in heating the vanes for about one hour at about a temperature of 1750 F. followed by air quenching of the vanes.

The gate has a cross-sectional area of at least about /2 square inch. This size gate will be suitable for the casting of vanes having a body with a wall thickness of as little as about of an inch even where the body is about 2 inches wide or wider. In other words, the /2 square inch gating cross-section will permit satisfactory flow of the molten metal during the casting through a sand mold having A inch spacing and 2 or more inches deep. In fact, a vane body wall thickness 7 6 of an inch is best used in the form of a tapered wall with the inner end of the channel tapering down to /1 inch in thickness. Also where the vane is only mounted by a flange at one side edge instead of both sides as in a double wheel arrangement, the body may taper down to the opposite side edge, again to a wall thickness of A inch. Highly effective casting of such a vane is obtained with a /2 square inch gate even when the vane body has an extra heavy lip at its discharge end, and the width of the vane body is as much as 5 inches or more. The vanes have thicknesses of i to inch with a floor width of /2 to 6 inches.

Where a single mounting flange is used at one'edge of the vane, it is preferably made in dovetail form. If desired the vane can have mounting flanges on each of its side edges so that it can be mounted between parallel side plates in a double dovetail-fashion. In this construction the mounting flanges on the vanes can have any kind of a shape so long as they fit in place in whatever mounting structure the side plates provide.

Turning now to, the drawings, FIG, 1 shows a throwing wheel assembly which includes a housing 20 in which is rotatably journaled a spindle 22 that carries a radially extending wheel mounting 24. To this flange is secured as by bolts 26, a runnerhead 28 which in'turn carries a set of vanes 30. A particle supply means which can be similar to that shown inthe above-identified patent, delivers blastan't particles to the center of the wheel between the'vanes in a space left open. The feed is controlled so that the particles-are supplied to the 'vanes at one limited portion of the vane-rotation path, and the housing is open, as indicated at 36, to permit the particles to dis charge from the vanes toward the work in the direction controlled by the particular location of the vane supply. The particular details" of the spindle mounting, housing construction, feed assembly, etc., can havedifferent constructions. Amore complete'description of these details as illustrated. in' FIG. 1, are included in copending application Serial No. 190,725, filed April 27, 1962.

As more clearly shown in FIG. 2, the runner head 28.

has-aplu ralityof. radially directed dovetail slots or grooves 38in eachoi which an individual vane, is mounted. The bolts 26 securing the runnerhead to the spindle flange 24, are shown as mounted in the floors 32 of the grooves 38.

Near the outer end of each groove the floor has a first recess 34-which is fairly shallow, and a second recess 40 which is deeper. A darn 42 just beyond the second recess is at floor level, and is cut by a channel 44 into two portions. The side walls 46 of-the groove are shown'as of dovetail shape except that near the outer end these walls, are relieved-as illustratedat 48.

The vanes are held in the grooves by gibs 49- (see FIG. 1) that have a springy tail 50 secured as by brazing to a wedge block 51 of triangular cross section. The outer end; ofdovetail flange on the vane has a wedge face 52' that engages a corresponding wedge face of the gib and jams. the outer end of the gib against the dam 42, under the influence of the centrifugal force developed by the rotation of the wheel. Mounting of the vanes is eifected by sliding a vane into its groove, and then slipping the gib in under it. The vane is arrangedto move into its groove about 1 inch further than illustrated wedged position, sothat the block on theouter end of the gibcan be inserted after the vane. After the gib is in place. they vane is pulled out into wedged position, and the springy tail of the gib squeezed between the floor of thev groove and thebottom of the vanes mounting flange keepsthe vane wedged. Removal of a vane is accom-, plished. in the reverse manner. The vane is driven inwardly asby hammering, to provide theabove clearance for the gib- A straight tool like a screw driver blade can.

then be slipped through the slot 44 to force the wedge block up overthe dam 42. Both the vane and the gib are then withdrawn.

The body of the vane is more clearly shown at 54 in FIGS. 5, 6 and 7, and has a channel-shaped face 56. Av bulbous enlargement 58 is provided on the back of the body at the outer end of the channel. Also this. end of the body is made to extend beyond the runnerhead 28. as well as beyond the outer end ofthe dovetai1ibase43. The. inner end of the channel can be beveled on its back SUI: face, as shown at 60.

FIG. 8 shows the bottom of the dovetail base and shows a group of three positioning lands or

webs

71, 72 and 73; Between them the base bottom is relieved and in the illustrated embodiment has two recesses 81 and 82-. In recess 81 there is a broken-away surface 70 where the casting gate is broken olf. There is no other gate used in this vane and neither the broken-away gate surface 70 nor any other partof the vane has any portion ground. The broken gatesurface can be in-a more recessed well 84. in the recess 81.

Land

72 or 73 helpin theremoval of a vane by pushing the gib out before it. For this purpose the outer end of the gib tail is bent so as to be in the path of these lands, which are usually spaced a little from the groove floor. The tail also urges the vane flange upwardly against the sides, 46 of the groove to help hold the vane accurately positioned in the runnerhead. After the wheel is used particles of abrasive and the like find their way into all available spaces and lock the vanes in place so securely that hammering is needed to remove them.

No grinding or finishing operation of any other kind need be used, and the resulting vanes show an exceedingly long life particularly where of the above composition, with very little premature erosion even though the vane bodies have a wall thickness of A of an inch or even of an inch.-

Othe-r abrasion-resistant steels such as other chromiummolybdenum steels with high chromium content (above 5%) can also be used to make good vanes in the above manner. Moreover I to 5% tungsten can take the place of an equal amount of the chromium in the above prefer-red steel,

Vanes cast from extremely abrasion-resistant steel such as that referred to directly above, require a generally larger gate cross-section than other steels such as those that can be cast against chills for hardening. However, regardless of the type of steel that is used for casting the vane, locating the gate on the recessed surface of the mounting flange enables the above important advantage in eliminating grinding.

The features of the present invention are also obtained when the gate is made in more than one portion, as by gating some metal through surface 81 and the remaining metal through surface 82, making the latter surface more extensive for this purpose.

Where the vanesare mounted between two side plates, mounting flanges or bases can be positioned at each side edge of the vane body and the gating provided on recessed portions of one or both of these side flanges. In general, side flanges when used on both sides of the vane,

can be made somewhat thinner. and less massive than the.

base 43. Alsothey need. not be dovetail but canbe of any shape and in fact can be simple extensions of the vane body.

FIGS. 11 through 18 illustrate further vane construction in accordance with the present invention. Here, the vanes 130 are held in a wheel 128 by plain dovetail'interarrangement andlocking pins 139. Adjacent one side of each groove 138 is a cylindrical pin socket 140 defining a cylindrical passageway which extends through a dovetail mounting base or flange 142 provided on eachvane. A notch 144 is formed in this base or flange so that a pin 139 can be passed through the notch and seated in the socket. This pin holdsthe vane in place in the groove and keeps it from being thrown out by the very high centrifugal forces generated by the. wheel rotation. round notch used with a pin that is round in cross-sectign is admirably suited for use in wheels operating at extremely high speed. For use at lower speeds both the notch and the pin can be angular, as for example square in cross-section. To help hold the vanes in place, as for example while waiting for the insertion of the pins, 2. simplev archedv leaf spring 150 is positioned in arecess 182 p rovided atthe bottom of the dovetail, and engages the door 154 of the groove.

Other vane lockingmeans may be used such as the torsion spring loaded pair of cone points with a double dovetail arrangement shown in Patent No. 2,819,562.

The vanes 130 can otherwise be quite similar to the vanes 30, with a body portion 155 and'a mounting flange 142. In addition to the bulbous enlargement 158, the channel 156, andthe bevel 160, the vane 130 also has a smalli bevel 162 at the inner end of the channel along the edge remote from the mounting flange, to make that cormet more difficult to break oli in handling and. the like. There are four lands, 171, 172, 173 and 174, at the bottom of dovetail flange 142, and between them three recesseslSI, 182 and 183. The broken off casting gate is shown in recess 182, although it can be. in either of theothers or in' more than one. Fewer lands and recesses, can also be used, although it is desirable to have at least two so located that the mounting spring can be fitted between and; have its ends engaged by them.

In the constructions illustrated in the drawings, the wheel is intended for rotation in conuterc lockwise direction, as seen in FIG. 2. This is represented by the arrows very little abrasion by the blastant particles. However,

the pins can beprovided adjacent the front surface of the vanes as by arranging for the pins not to project up above the face of the runner head. With such a pin arrangement a single pin socket at each dovetail groove can be used regardless of which way the wheel is rotated.

It is generally desirable to have the pins arranged so that they can be extracted as by a gripping tool. Thus, a narrowed neck can be cut around the projecting head of the pin. Where the pin head does not project, its outer face can be recessed to provide a gripping anchorage, as by drilling and threading a socket in this face.

The vanes 3'9 which do not use locking pins need only one type of runner head for rotation in either direction. The vanes (30 or 130) themselves need not be made reversible, but if they are so fashioned, they can be made somewhat thicker than the 7 inch figure mentioned above, in order to keep the outer edges of the vanes from Wearing away too soon.

As seen in FZGS. 18 and 19 a round locking pin 139 for locking the vane to the runner head or throwing wheel has a somewhat flexible metal spring S secured thereto. The anchor end of the spring S is supported within a horizontally extending channel C drilled through the lower portion of pin 139. The remaining portion of the spring S extends axially of the pin shaft and has an outwardly extending bend therein. The axially extending portion of spring S rides in axially extending groove S in the pin shaft. When inserted in a pin socket 148 against the vane in the runner head, the walls of the socket urges the outwardly bent portion of the spring S inwardly against the pin shaft to provide a force fit whereby the vane is locked in position. With this arrangement, an additional pin locking force, in addition to the normal centrifugal force developed during operation, is provided.

A further locking pin arrangement is shown in FIGS. 20-22. Here, the pin 26% is not of a true round shape. The pin 2% is so machined that one side thereof presents a fiat surface 202 along which the axially extending portion of the spring extends. The spring S has its anchor end extending through a horizontally extending channel C in the lower portion of the pin shaft as with the embodiment of FIGS. 18 and 19. In addition, however, the channel C terminates, in one form, in an elongated detent or cut-out portion 204 extending transversely of the pin axis, and the extreme anchor end of the spring S is bent over at a right angle to lie within said slot, thus locking the spring S firmly to the pin 280. Instead of the transverse cut-out portion 204, the shaft can be machined along this area to provide an inwardly extending arcuate shaped detent or face.

A somewhat different vane and pin socket arrangement in the runner head is used with the locking pins of E68. 20-22. As seen in FIGS. 25-27, the vane 206 has a different shaped cut-out 208 for accommodating the FIGS. 20-22 pins. The cut-out 208 of the vane cooperates with the pin socket 211 of the runner head 212 (see FIGS. 23 and 24) when the vane is supported in the head to provide a pin seating socket for the pin 200 when assembled for operation. As seen beter in FIG. 23, the socket 210 of the runner head 212 has a straight side lying opposite the cut-out 208 which is relieved by an outwardly extending detent 215 to accommodate the axially extending portion of the spring S.

The advantages of the present invention, that is the relatively long vane life and simplicity of manufacture, are also obtained with vanes having special configurations such as that shown in US. Patent No. 2,983,082.

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A cast vane for a throwing wheel that projects a' at least one side edge of the body for engagement in at least one mounting slot of the wheel, the flange having a recessed face and the recessed face having a broken-off casting gate that is confined within the recess, the vane being free of ground surfaces and the vane body being free of casting gates.

2. The combination of claim 1 in which the vane is an abrasion-resistant chromium molybdenum steel having a high chromium content, and the gate has a cross-sectional area of at least about one-half square inch.

3. The combination of claim 2 in which the steel has the following composition: 2.5-3.5 carbon, 12-26% chromium, 0-6% molybdenum, 0-4% vanadium and the balance being iron.

4. The combination of claim 2 in which the channelshaped vane body has a floor with a wall thickness of about -9 inch except at the ends of the channel, and the floor is about /2-6 inches wide 5. An abrasive throwing wheel assembly that projects a stream of particles fed to it comprising a rotatable wheel, a vane having a channel-shaped body, an integral mounting flange formed along at least one side edge of the body for engagement in at least one mounting slot of the wheel, the flange having a recessed face, a broken-off casting gate that is confined within the recess, the vane being free of ground surfaces and the vane body being free of casting gates, a notch in said flange, a socket in said mounting slot of the wheel lying adjacent and extending below said notch, a locking pin inserted in said socket to be flush against said notch, said pin comprising a round shaft, a horizontally extending channel through the lower portion of the shaft, a spring having its anchor end extending through said channel with the opposite end extending axially of said shaft, and an outwardly extending bend in said axially extending portion of said spring.

6. The assembly of claim 5 wherein the locking pin shaft has an axially extending groove and said opposite end of said spring rides in said groove.

7. The assembly of claim 5 wherein the locking pin on one side has a flat surface along which the axially extending portion of said spring extends, and said channel terminates in a detent in the pin shaft which extends transversely of the pin shaft for accommodating a bent over end of the anchor end of the spring in said channel.

8. An abrasive throwing wheel having spaced-apart channels extending radially of said wheel, a throwing vane supported in each channel, an arcuate shaped cut-out formed in one side of the vane, a socket formed in said throwing wheel immediately adjacent the cut-out portion of said vane, the side of said socket opposite the cut-out of the vane being straight with an outwardly extending relieved portion in said straight side, a locking pin of round shape except for one side which has a flat surface seated in said socket with the round portion thereof lying adjacent the arcuate cut-out portion of the vane and with the fiat surface thereof lying adjacent the straight side of the socket in said wheel, and with said relieved portion accommodating a wedging spring secured to said locking pm.

References tilted in the file of this patent UNITED STATES PATENTS 926,568 Huey June 29, 1909 937,402 Wood et a1. Oct. 19, 1909 2,204,633 Turnbull June 18, 1940 2,376,639 Unger May 22, 1945 2,582,702 Keefer Jan. 15, 1952 2,732,666 Powell Jan. 31, 1956 2,798,403 Launder July 9, 1957 2,798,827 Hanink July 9, 1957 2,869,289 Gossard June 20, 1959 2,906,651 Saives Sept. 29, 1959 2,983,082 Gossard May 9, 1961 3,015,248 Spurlin Jan. 2, 1962 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,151,417 October 6, 1964 Edward L. Hartman et al.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 69, after "or a" insert double wheel assembly (supported between two circular shaped plate-s) the flange having a recessed face and the recessed face having a broken-off casting gate this is confined within the column 2, lines 19 to 21 strike out "The heat treatment for the thin vanes consists in heating the vanes for about one hour at about a temperature of 1750 F. followed by air quenching of the vanes."; column 4, line 67, for "tot he? read to the line 71, for "pin" read pins column 5, line 57, for "beter read better Signed and sealed this 9th day of March 1965,

(SEAL) Attest:

ERNEST W. SWIDER EDWARD. J. BRENNER Attesting Officer Commissioner of Patents

Claims

8. AN ABRASIVE THROWING WHEEL HAVING SPACED-APART CHANNELS EXTENDING RADIALLY OF SAID WHEEL, A THROWING VANE SUPPORTED IN EACH CHANNEL, AN ARCUATE SHAPED CUT-OUT FORMED IN ONE SIDE OF THE VANE, A SOCKET FORMED IN SAID THROWING WHEEL IMMEDIATELY ADJACENT THE CUT-OUT PORTION OF SAID VANE, THE SIDE OF SAID SOCKET OPPOSITE THE CUT-OUT OF THE VANE BEING STRAIGHT WITH AN OUTWARDLY EXTENDING RELIEVED PORTION IN SAID STRAIGHT SIDE, A LOCKING PIN OF ROUND SHAPE EXCEPT FOR ONE SIDE WHICH HAS A FLAT SURFACE SEATED IN SAID SOCKET WITH THE ROUND PORTION THEREOF LYING ADJACENT THE ARCUATE CUT-OUT PORTION OF THE VANE AND WITH THE FLAT SURFACE THEREOF LYING ADJACENT THE STRAIGHT SIDE OF THE SOCKET IN SAID WHEEL, AND WITH SAID RELIEVED PORTION ACCOMMODATING A WEDGING SPRING SECURED TO SAID LOCKING PIN.