US2131767A - Apparatus for treating metal - Google Patents

Description

Oct. 4, 193.18.

D. C. TURNBULL APPARATUS FOR TREATING METAL Filed July '1, 1936 4 Sheets-Sheet l iOct` 4, 1938.. i n, c. TURNBULL 2,131,767

v APPARATUS V FOR TREATING' METAL 4Filed July 1, 195e 4 sheets-sheet 2 ATTORNEY I Oct. 4, 1938. D. c. TURNBULL .APPARATUSJv Fon' TREATING METAL Filed July 1-, 195e 4 sheets-sheet s lNvENToR ,Band Zim/z Zul/ZZ.

Oct. 4, 193& D. c. TURNBULL.

' APPARATUS Fon TREATING METAL,

Filed July l, 1936 4 Sheets-Sheet 4 INVENTOR ,Dawd 6. Zur/wall.

ATTORNEY Patented mirri-:b STATES.

PATENT 'orifice APWPARATUS FOR TREATING METAL David c. Tdrnhuu, nnshawm', rnd., assignnr'm American Foundry Equipment Company, Mlahawaka, ind., `a corporation of Delaware Application .hay` 1, 193s, semi- Nasazsz 12 This inventionrelates-to apparatus'for treating metal and more particularly to apparatusl for cleaning, polishing, hardening or otherwise treating the surfaces of castings, Vforgings-.and

shaped that they can be tumbled about, they can generally be effectively treated in a tumbling mill. However, where the articles are large, irll regularly shaped, brittle or fragile they cannot be so cleaned and treated and other methods and apparatus must be employed. l

An object of this invention is `to provide an. imroved v apparatusior uniformly treating or cleaning the surfaces 'of irregularly shaped, or large, brittle'or fragile articles by continuous operation.

Other objects of this invention will become apparent from the disclosure. l Accordingtothe present invention, the articles to be treated are 'deposited on a conveyor and advanced through the stream of treating matel rial in such a way that all portions, or predetermined selected portions, Voffeach article are exposed for treatment by the stream. Each article is advanced along a predetermined path through the stream and is turned about an'axisextending transversely tothe direction of advance movement of the article. Preferably the treatingmaf terial is projected against the articles from two opposite directions in fan-like streams so that the treating materialwill strike all selected surface portions of the articles including the surfaces of cavities and projections.

40 The apparatus for carrying out the invention preferably includes a conveyor having a plurality of spaced and generally parallel 'supporting elements adapted to support the articles to be treated and-fito advance them along a predetermined lineal path and at the same time turn them about to expose all surfaces or selected surfaces of the article to the abrasive stream. 'I'he supporting elements may comprise belts actuated at diiferent relative speeds, thereby to eifect aturning move- 5'0 ment of the articles during forward movement as they are being'treated.- Preferablyltheabrasive throwing wheels or projectors are arranged v so that one or more of them projects a stream of treating material from above and one or more projects the treating material'from below,\there by treating both upper and lower surfacesof the articles substantially simultaneously. y

-The Ypresent invention provides apparatusA whereby relatively large. heavy or irregularly shaped articles such as castings, forgings and `s l yother machineand structural parts of `various yshapes can be quickly `and easily cleanedpor" treated. The apparatus permits the cleaning operation to be carried out continuously and substantialiy automatically. If desired, aut0matic 10" apparatus may be provided forsupplying -.the articles vto the treating apparatus aini'conveyins` them therefrom.,

"me apparatus is simple and rugged VandJis'easyv n toconstruct and operate. There is la. "il

-of the apparatus exposed to the wearing action` of the treating material and theparts thusy exposed can be quickly and easily repaired or replaced.. The principal bearing portions of the apparatusall -areeifectively sealed against entry 1.20 of' yabrasive particles and thus are life'` and of injury.

Various other features and advantages rof the j invention will be apparent from the followingparticular description andv from an inspection of the 25 l accompanying drawings.

Although 'the' novel features whichv are believed to be characteristic of thisinvention will be particuiarly pointed out inv the claims appended hereto', the invention itself. as to its objects and 30 Y advantages; and the manner in which it may beL carried out. may be'better understood lby refer-,

l ring to the following description taken in conj nection with vthel accompanying'drawings forming a part thereof', in which: l

Fig. 1 is aside elevational view of onei'o'rm oi! apparatus suitable for carryingout the inv vention, certain parts being shown in section ltov expose the interior construction this-view'being taken along line i-i-I of Fig. 5;.

Fig. 2 is 'an enlarged transverseA tional view taken along line 2-2 oi Fig.' 1;

Fig. 3 is a top plan view of the complete ap-` Daratus; Fig. 4 is a cross sectional view taken along line '45 Hon-"iai: v

Fig. 5` is an endjelevational view of the appa-i f ratus viewed from the discharge endthereof; and Fig. ii is Aa somewhat diagrammatic sectional view of a throwing wheel used to'project the 50 abrasive stream. y In'the following description and in the claims,

. various ,details will be identified by Specific namesy for; convenience, but they are ,intendedto be as generic in their'application as the will per- Q55 mit. Like reference characters denote like parts in the several figures of the drawings.

In the drawings accompanying and forming part of this specification, certain specific disclosures of the invention are made for purposes of explanation, but it will be understood that the details may be modified in v'arious respects without departure from the broad aspect of the invention.

Referring to the drawings, the apparatus includes a housing structure I having a treating chamber 2. The housing I is provided with an inlet or charging opening 3 and an outlet or discharge opening 4. Adjacent the charging opening 3 is a charging vestibule 5closed by one or more iiexible curtains 6. Adjacent the discharge opening 4 is also. a discharge vestibule 1, closed by one or more exible curtains 8. Extending between the charging opening 3 and discharge opening 4 is a conveyor 9 (described more in detail hereinafter), adapted to support articles to be treated and convey them through the treating chamber 2.

Suitably mounted on the top wall of the housing I and adapted to project a stream of abrasive a against articles d on the conveyor 9 is an abrasiveprojector IIl, which preferably is ofthe centrifugal throwing wheel type. Although the abrasive projector may take other suitable forms, preferably it comprises a plurality of spaced throwing blades 'I2 extending from adjacent the periphery of the wheel inwardly andterminating short of the center of the wheel to. define a generally central opening I4. The blades may be supported upon a frame such as one or more side plates II. The hub portion I3 of the wheel is connected to a rotatable shaft 25 mounted in Y suitable bearings I5. Disposed in the circular space I4 between the inner ends of the blades I2 is an impeller I6 having a plurality of radially extending vanes I 1 which preferably rotates with the i throwing blades I2. An independently mounted normallystationary control member I8 may be interposed between the impeller I6 and wardly along the blades I2 by centrifugal force' and is projected from the blades I2 adjacent the periphery of the wheel by combined centrifugal and rotational force. y

'I'he treatingmaterial is projected from the wheel in the form of a fan-like stream which diverges from its point of emergence and irnpinges the-articles in the form of an elongated impingement pattern. The direction of flight of the stream a relative to the wheel can be regulated and determined by a proper adjustment of the clock dialposition of the opening I9.

The wheel is preferably arrangedso that the articles carried by the conveyor 9 pass through the stream a in a direction extending substantially along the longer axis of the impingement pattern and are struck by treating particles from angles varying throughout sixty degrees or more. The range of angularity may vary considerably but generally will be selected so that .it ap- Droaches 90. i

A suitable opening 24 may be provided in the top wall of the housing 2 to permit the passage 0f the abrasive a into' the treating chamber. Preferably a portion of the wheel I0 projects through this opening and into the treating chamber. A suitable protective housing 26 may be disposed over the wheel to enclose the major portion thereof.

Disposed below the conveyor 9, and preferably in substantially the same vertical plane, is a second abrasive projector 30 which may be similar in all respects to the wheel III Aand may be rotatably carried on a shaft 3| extending through an opening 32 in the' housing walland journalled in bearings 33. 'The wheel 30 may be driven from a motor 34 in a manner similar to the projector I0. The projector 30may be disposed directly below the projector Il or it may be offset longitudinally as shown in Fig. 1 in the illustrative drawings.

A hopper 35 containing treating material is disposed in a suitable position preferably above the projectors I0 and 30. The hopper is connected to a main conduit 3 leading into branch conduits 31 and 38, which supply treating material to the feed pipes 20 leading to the projectors Ill and 30, respectively. The conduits 31 and 38 and dfeed pipes 29 may be suitably supported by brackets 2| and 39 connected to the adjacent structure.

'Ihe treating material used will depend upon the work to be performed. vIt is understood that the terms treating metal or fabrasive" is intended to refer to any suitable granular material ranging from relatively large to relatively small particles and from smooth non-cutting particles such as hard=steel shot, to highly abrasive particles such as cracked steel grits or sharp quartz sand. Where a relatively smooth surface is desired the particles may be line and relatively smooth and non-abrasive, andwhere a roughened or stippled surface is desired, particles having abrading characteristics are selected.

The bottom wall of the housing is inclined to provide al hopper 45, whichA may be disposed if desired in a pit 46 below the surface of the door. The hopper leads to and communicates with an open trough 41 provided with a screw conveyor 48, adapted to conduct spent abrasive toward the center-of the trough 41. Communicating with the trough 41 and leading to an elevator 50 is a second trough 49 having a screw conveyor 5I. The elevator 50 may include an endless belt 52 trained over drums 54 and 55 and carrying a plurality of buckets 53. The conveyor 48 is driven from a motorand reducer set connected as by the belt drive 62 to a pulley 63 attached to the conveyor 48. 'I'he conveyor 5I may be driven in a similar way from the motor and reducer set 60' through a belt drive 65, and

a pulley 61. The conveyors cooperate to carry the spent abrasive from the hoper 45 to the elevator 50. The elevator 50 is driven by a motor 10 driving a speed reducer 1I which in turn drives a suitable belt drive 12 which rotates the upper drum 55. The abrasive is elevated from the bottom of the elevator 50 to the top thereof and discharged into the hopper 35 from whence it can flow by gravity to the projectors I0 and 30.

The conveyor 9 may include a pair of spaced and generally parallel endless flexible belts 89, each of which is trained around drums 8| disposed outside the front and rear end walls of downwardly and inwardly and an upstandingguide iiange 99 at its outer edge and a depend- `ing stiiening flange 9| atits inner edge. The supports 99 are suitably spacedand constitute with the belts 99 means .for supporting and advancing articles d to be treated through the treating chamber.A

1 5 The lower night of each belt 99' may be trained over one or more rollers 95' rotatably mountedvr by shafts 99 suitably journalled in the housing I. It will be seen that the upper flight of each continuous belt 99- enters the housing through the 29 charging opening 9, movesthrougii the treating chamber Zand leaves Vthe housing through the discharge Iopening 4. Suitable lower openings (not shown) are provided in the end walls of the housing i f or 4permitting thepassage of the lower ilight. A iiexible curtain or brush 91 may be provided adjacent the last supporting'roll '.95

and similar brushes 99 may be disposed adjacent the belt opening in the housing for removing spent abrasive from each belt 99 before it 99 passes from thetreating chamber 2.

Preferably, eachlbelt 99 is driven by a motor |99, driving a speed reducer |9|, which is .con-

nected as by a chain drive |92, to a sprocket |93 carried on the drum shaft 92at one end of the apparatus. Energization of the motor |99'eilects rotation of the corresponding drum 9| and causes the belt 99 to-travel along its path. The be1ts99 may be driven from a single sourcel of power but it is desirable that the speed of each 40 belt 99 be individually controllable.` i v Preferably, the belts laredriven at different' forward speeds so ,that the articles carried therel 'on are caused to rollorrotate.. If desired, one

of the belts may be driven in a reverse direction but in this event, the other b elt should have a forward speed in excess of the rearward speed of the iirst belt.

If desired, suitable charging vand discharging `apparatus may be provided adjacent the charg- 5 ing and discharging ends, of the apparatus, re-

spectively. The articlesto be treated may be transported'to the conveyor and removed therefrom automatically if desired. However, the

specific structure of such automatic conveyors forms no part of the present invention and any suitable automatic conveyor may be employed. Forfthe purposes of illustration, there is shown a loading chute |95 supported by bracket |99,

which chute is inclined toward and extends to so the loading end of the upper flight of the belts 99. A discharge chute |91 may extend from the l discharge end of the upper flight and may be suitably supported by bracket |99.

The present apparatus issuitable for treating various shapes and sizes of articles and is admirably adapted for treating articles having a substantially circular or cylindrical body portion as, for example, wheels, brake drums, receptacles and various other articles., For` the purpose of illustratiom'there isfshown a plurality ofbrake drums,d each `olf which has a cylindrical rim portion w and a projecting hubh.

` The operation of the apparatus is as follows:

The abrasive projectors I9 and 39 are driven by the motors 32 audit, respectively, and are sup- Chamber. l

need be shut down only for repairs.

plied with abrasive from the hopper .99 in the 4manner above described and project abrasive streams a and b respectively, into the treating The'articles d to be treated are successively placed upon the loading chute |95 and slide by gravity or are otherwise urged on to the 'belts 99, each of which supports an edge portion of the rim w. The motors |994 are energized and drive 'the belts 99, thereby advancing the drums d through the 'charging 4vestibule and into 10 the treating chamber.

The articles d advance forwardly ,within-the chamber and enter the abrasive stream a which impinges against the top surface of the rinrw and the leading surface of thev hub h. Prefer- 15 ably the belts 99 are driven at different speeds,

thus effecting rotation of each article d about its vertical axis. This rotation brings successive portions of the horizontal top surfaces and the vertical surfaces into the stream a, where they $0- aresuitably treated. Aseach article d advances through the stream, it is struck by abrasive 'approaching from angles which vary as the articles' advance. Thus, the surfaces of the cavities and projections are effectively subjected to the effect 25 ofthe stream.

As the article d is advanced further, it leaves the stream a and enters 'the stream b, which .treats the lower surfaces of each article d in a manner equivalent to the treatment of the upper surfaces by the stream a. Each article then passes out through the discharge vestibule 1 ,and

isdeposited on the discharge' chute |91 by `which it can be -transportedaway from the treating apparatus. as,

It will be noted from an inspection of the drawings that articles having a diameterA considerably greater-than the width of the abrasive streams aand b may be effectively cleaned by the apparatus disclosed due to the fact that the '40 articles dfare rotated about an axis lying ina vertical plane passing substantially midway'between the supporting elements and approximately medially of the streams a and b. Thus,

the articles d are continuously 4in the streams i5 and the several portions are carried through each `stream preferably'a number of times during the course of a single trip through the apparatus. The speed of the articles d through the treating chamber is controlled so that the articles` are ex- 50 posed to the abrasive for the 'desired time and. the relative speeds of the belts 99 are adjusted so' that' thearticles rotate the desired numberr of times in passing through the treating chamber.

-. The provision of the required number' of pro- 55 vjectors both above and below the conveyor so arranged as to treat both theupper and lower vsurfaces of articleson the conveyor -permits. the

articles to be fully treated in the course of a singleA trip through the apparatus. It is innemendthat 00 any `number of wheels Yorprojectors' placedV in staggered relationship or otherwise arranged may be used as conditions require. The articles to betreated may be supplied atzone end of the apparatus and removed at theother, and the apparatus operated continuously so the apparatus Preferably the belts 99 `are so arranged that the rim portions of the articles'only bear on the belts. thus permitting lthe articles yto roll relatively freely on the belts. -This 'insures a relatively smooth, even rotation ofthe articles on the conveyor. Also, the inclination of the belts 99 causes the articl to-assume a central posi- 75 tion relative to the conveyor and thus uniform treatment of the articles is insured.

In certain cases, one of the belts may be omitted and the remaining belt driven in the manner above described. In that case, the single belt imparts a rotary movement to each article and causes the article to roll along while supported by the support 90 at one side and the belt 80 at the other side. A

It will be noted that substantially no portion of the apparatus is directly in the path of the abrasive red by the vthrowing wheels, the articles 'd to be cleaned being juxtaposed as shown in Fig. 1 to receive the full force of the abrasive red by the wheels. The flexible curtains 5 and 8 bear upon the belts'80 and prevent the escape of spent abrasive and the. brushes 91 and 98 brush the abrasive off from the conveyor. Substantally all of the bearing portions of the apparatus are disposed outside of the housing and thus there is little opportunity for abrasive working into the bearings. In this connection, it will be noted that the supporting rolls 95 for the belts preferably are spaced sufliciently to permit the abrasive streams to pass therebetween. 'I'he supports 90 preferably are also spaced sufciently to be out of the path of the abrasive.

The apparatus may be suitably modied to handle various types of articles, and thus it is apparent that various modifications may be made in the apparatus without departing from the spirit of the invention. Preferably, the supports 90 and belts 80 are of suiiicient width to accommodate a considerable range of sizes of articles. 'I'he belts may be made of various materials having suitable strength and wearing qualities and of suillcient flexibility to assume the shape required to properly support and manipulate the articles supported thereon. The belts may be formed of rubber, fabric, connected metal bars, interconnected links or various other suitable materials.

The apparatus is adapted to convey articles -of various shapes and sizes and the articles may be positioned so that they are substantially supported by and extend above the supports or alternatively the article may be mounted on the supports in an inverted position from that shown in the drawings so that the articles are suspended downwardly between the supports. This inverted arrangement may be advantageous in certain cases where the article is so shaped that it might otherwise tip over.

While certain novel features of the invention have been disclosed and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes may be made by those skilled in the art'without departing from the spirit of the invention.

What is cl/aimed is:

1. Apparatus for abrasively treating metal articles including, a plurality of endless conveyr belts, means mounting said belts in spaced and generally parallel relation to support the articles to be treated therebetween, an abrasive throwing wheel operative to project a stream of abra.- sive and means for driving said belts at different relative speeds-thereby to turn said article about an axis transverse to it's forward movement simultaneously with its forward movement through said streams. ,a ,Y ,f

2. Apparatus for treating metal articles including, means for projectingl a. stream of abrasive particles, a pair of spaced article-supporting belts, article guiding means associated withsaid, spaced. belts, means for driving said beltsy at dif-1 ferential speeds so as to cause the articles supported thereon to rotate while advancing through the stream, and means for supporting the upper run of said belts transversely inclined toward one another. l f

3. Apparatus for blast cleaning metal articles including, a housing, an abrasive -throwing wheelv operative to project a controlled fan-shaped .stream of abrasive into said housing, and conveyor means extending through said housing and adapted to advance articles to be treated through said stream, said conveyor means including a pair of spaced and generally parallel supporting elements, endless belts having portions riding on said supporting elements, drums disposed outside of said housing and having driving engagement with said endless belts, and means for driving said drums to selectively advance said endless belts at desired differential speeds.

4. Apparatus for treating metal articles including, a housing, a plurality of spaced and generally parallel endless belts extending through said housing, a driving drum for each of said 'endless belts disposed outside of said housing,

means for driving said belts at diierential speeds, guide members extending through said housingand adapted to support and guide the upper flights `of said endless belts, spaced supporting and guiding rolls adapted to support the lower flights of said endless belts, an abrasive throwing wheel operative to project a fan-shaped streamof abrasive having anelongated impingement pattern, said wheel being arranged iso as to place said elongated pattern between said spaced belts, and sealinggmeans for the upper and lower'ights of said belts respectively for` preventing the escape of treating material from said housing.

5. Apparatus for blast cleaning and removing scale and other foreign undesirable materials from the surface of metallic objects including, an abrasive throwing wheel operative to project a fan-shaped stream of abrasive having an elongated impingement pattern, spaced conveyor elements positioned on opposite sides of said Wheel, means for advancing said conveyor elements at diierential speeds and in the general direction of the longitudinal axis of the impingement pattern, thereby to turn an object about an axis transverse to its forward movement simultaneously with its forward movement through said stream.

6. Apparatus for blast cleaning metal articles including, an abrasive throwing wheel operative to project a fan-shaped stream of abrasive having an elongated impingement pattern, a plurality of spaced guiding elements for the articles to be treated positioned outside of the path of the projected abrasive stream, means for advancing the articles to be treated along said guiding elements through said stream in the same general direction as the longitudinal axis of said impingement pattern, and means for imparting a higher velocity in aforward direction to an 'article along one of said guiding elements than along another of said guiding elements whereby to rotate each article about an axis transverse to its direction of forwaro movement. ,g

7. Apparatus for abrasively cleaning metal articles including, an abrasive throwing wheel operative to project a stream of abrasive, a plurality of spaced and generally parallel conveyor members adapted to support an article' to be treated, and means for driving said conveyors'at selected differential speeds to carry the article through said stream and simultaneously rotate the same in said stream.

8. Apparatus for blast cleaning metallic Aar ticles including, a plurality of spaced supporting elements, an abrasive throwing wheel operative to project a fan-shaped stream of abrasive have ing an elongated impingement pattern, said wheel being arranged so as to direct said abrasive stream between said spaced supporting elements, means for :guiding the article to be cleaned through the abrasive stream, and means for imparting a higher velocity in a -forward direction to the `article to be cleaned along one of said supporting elements than another of said supporting elements whereby to rotate said article in said stream.

9. Apparatus for blast cleaning metallic articles including, an abrasive throwing wheel operative to project a fan-shaped stream of abrasive at blasting velocities, a pair of spaced and generally parallel supporting elements, conveyor means extending along said supporting elements for carrying the articles to be treated, means forl driving said conveyor means at dierentlal speeds `to simultaneously rotate andv advance the armeans for driving said conveyor members at selected diierential speeds to convey the work piece through said streams and rotate the work piece in said streams whereby both upper and lower surfaces of the work piece supported on said conveyor members are subjected to abrasive treatment.

l1. In an abrading machine, a pair of endless conveyor belts, means mounting said belts in spaced and generally parallel relation with the supporting surfaces thereof positioned to support and conne a work piece to be treated therebetween, an abrasive throwing wheel operative to project a stream of abrasive at abrading velocities against the work piece supported on said belts, and means for driving one of said belts at a higher velocity in a forward direction than the other belt whereby to rotate the work piece under treatment in the yabrasive stream and advance the work piece through said stream.

12. Apparatus for blast cleaning and removing scale and other `foreign undesirable materials from the surface of metallic objects including, an abrasive throwing wheel operated to project a fan-shaped stream of abrasive having an elongated impingement pattern, spaced conveyor elements positioned on opposite sides of said wheel, means for advancing said conveyor elements at differential speeds and in the general direction of the longitudinal axis of the impingement pattern thereby to turn the object under treatment about an axis transverse to its forward movement, said conveyor elements having their respective supporting surfaces transversely inclined toward one another whereby the object supported thereon has a limited area of contact therewith.

' DAVID C. TURNBULL.

Images