US2310384A - Apparatus for treating metal articles - Google Patents

Description

Feb. 9, 1943.A R, F; ARNLDY 2,310,384

AT PARATUS FOR TREATING METAL ARTICLES Filed Aug. 2, 1940 3 Sheets-Sheet 1 ROMA F. ARNOLDY BY l ATTORNEY F6119, 1943. y Rl F ARNO'LDY A 2,310,384

APPARATUS FOR TREATING METAL ARTICLES Filed Aug. 2, 1940 s sheets-sheet 2 lo /0 5 66 l I4' Z 65 62 O .fo ff s A A i f 1 5 50 /5 /5 "67 g 7a y ROMAN F. ARNOLDY BY LE1-LWNM-,

ATTORNEY Feb. 9, 1943.

R. F. ARNoLDY APPARATUS FOR TREATING METAL ARTICLES vFiled Aug. 2, 1940 MW M I5 Sheets-Sheet 3 INVENTOR ROMAN E ARNOLDY ATTORNEY insufficient.

Patented Feb. 9, 1943 amarsi APPARATUS ron rename. METAL ARTICLES Roman F. Arnoldy, Houston, Tex., assignor to The Linde Air Products Company, a corporation of Ohio Application August 2, 1940, Serial No. 349,456 I Claims.

This invention relates to the treatment of elongated metal articles, and to the hardening of surface portions thereof by the applic-ation of high temperaturev heat, preferably followed by the application of a suitable cooling medium; and more particularly to apparatus for flame hardening cylindrical surfaces of elongated metal articles,

instances in whichy other sources ofhigh temperature heat are utilized.

such as the interior or exterior surfaces of tubes,

To provide a greater resistance to wear and abrasion, it is often desirable to produce on a metal article a surface portion or case having a greater hardness than the remainder of the article, since the unhardened portion remains tough and ductile whereas if the entire article were hardened the resultant ductility would be An extremely e'ective method of producing such a surface' portion or case has been found to be name hardening, in which 'high Vtemperature heating flames, such as those produced by the combustion of a mixture `of oxygen and acetylene, or other suitable gases, are applied to a surface in order to heat the metal to a desired depthl and to a temperature at or above the critical range, after which the heated metal is cooled rapidly to produce a hardened structure. In some instances, the entire surface portion is heated and then cooled, while in other instances successive portions are heated and cooled in a progressive manner. 'I'he principles of this invention have their greatest applicability to the latter or progressive method.

Furthermore, a variety of cooling 'methods have been employed. Air hardening steel, for instance, will harden upon natural cooling, andthe surface portion to be hardened need only be heated;

It is not only desirable but also necessary in most applications of surface or flame hardening to produce a uniform hardness, both laterally or circumferentially and also-longitudinally of a surface or portion thereof. A shaft or rod for moving the piston of a reciprocating compressor, for instance, must have a. uniform hardness longitudina11y,.or unequal wear will occur which will cause the shaft not only to rock in its bearings, but also cause leakage past the packing; and the rod also must have a uniform circumferential hardness, or unequal wear will cause packing leaks at various circumferential points; Similarly, a tubular linerfor the cylinder of a pump or compressor,` for instance, must be provided, must be provided with an inner surface having a uniform hardness both circumferentially and longitudinally, or unequal wear from the piston travelling thereover will result in grooves or depressions at which the rings ordi-A narily employed will be unable to prevent leakage.

A cylindrical surface of a metal article may be hardened by applying high temperature heat to successive circumferential zones thereof, and effecting a relative rotational movement as well as a relative longitudinal movement between the surface to be hardened and the source of heat. Apparatus for flame hardening a cylindrical surface of a metal article in this manner may include a carriage movable upwardly and downwardly along a vertical framework. In name hardening an exterior cylindrical surface of a metal article such as a shaft, the article is mounted for rotation in a vertical position, and

while the usual rail steel normally requires only the application of an air quench to produce sufilcient cooling for hardening. However, the great majority of metals require the application of a water or similar quench to effect the sudden or rapid cooling necessary to produce the desired hardness, andthis invention will be explained with reference to such cooling, although it will be understood that other methods of cooling may be employed Where the nature of the metal or other considerations indicate that such other methods are desirable.

. In addition, heating has been accomplished by means other than high. temperature heating' flames, such as by electric arcs, and while this invention is to be explained with reference to lheating flames, it will be understood that the principles of this invention may be applied to a heating and quenching device, which directs a plurality of heating flames inwardly against a circumferential zone of the surface of the shaft and a plurality of quenching jets beneath the heating flames, is mounted on the carriage, which is moved upwardly. In name hardening an interior cylindrical surface` of a pump liner or the like, the article to be treated is mounted for. rotation on the carriage and moved downwardly past a stationary heating and quenching device. While such apparatus is eminently satisfactory for llame hardening relatively short shafts, cylinders, rolls, tubes, pump liners, and the like, the length of article which can be treated is limited by the height of the framework and also by the relation between length and diameter, which -in many instances is sutilciently great so that the article lacks suflicient stiffness to be supported between centers or from beneath. Furthermore, with previous quenching devices, it is difficult to direct the quenching jets against the heated surface as close to the heating flames as is often desirable.

Among the objects of this invention are to provide novel apparatus for treating a cylindrical surface of a relatively long metal article, such as a shaft, tube, or the like, and particularly an article of such length that it cannot be supported between centers or from beneath; to provide such apparatus in which relative rotational and longitudinal movements between the article and a treating device are effected; to provide apparatus by which such an article is simultaneously rotated and moved downwardly with respect to a heating and quenching device, and the article is accurately guided during such movement; to provide a novel quenching device by which quenching jets may be directed against the heated surface portions at points more closely adjacent the heating iiames, but without interfering with the operation of the heating flames; and to provide such apparatus which is economical to manufacture and relatively easy to operate.

Other objects and novel features of this invention will become apparent from the following description and accompanying drawings, in which:

Fig. 1 is a front elevation of apparatus constructed in accordance with this invention, by which a relatively long shaft is being treated;

Fig. 2 is a horizontal sectional view taken along line 2-2 of Fig. 1, looking downwardly on a heating and quenching device which forms a part of the apparatus of Fig. 1;

Fig. 3 is a partial horizontal sectional view taken along line 3-3 of Fig. 1, looking downwardly on a special guiding and rotating device which forms a part of the apparatus of Fig. 1;

Fig. 4 is an enlarged vertical sectional view, taken along line 4-4 of Fig. 3, through the special guiding and rotating device;

Fig. 5 is an enlarged vertical sectional viewl taken along line 5-5 of Fig. 2, through the heating and quenching device;

Fig. 6 is a bottom view of a drive collar which forms a part of the special rotating and guiding device; and

Fig. 'l is a top view of an assembly which also forms a part of the special rotating and guiding device and which includes a raceway for the drive collar of Fig. 6 and a guiding bushing for the shaft being treated.

In accordance with this invention, a cylindrical surface of an elongated metal article is treated by suspending the article from the upper end vso that the axis of the cylindrical surface is disposed substantially vertically and so that the article is relatively freely rotatable, rotating the article about the axis of the cylindrical surface, effecting a relative movement in a vertical direction between the rotating article and a treating device adapted to treat a limited vertical portion or a circumferential zone of the cylindrical surface, and restraining the lateral movement of the article at points a relatively short distance apartone point preferably being located. above the treating device and the other point preferably being located below the treating device. When all or a portion of the cylindrical surface is to be hardened, the treating device is preferably a stationary heating and quenching device'adapted to heat and cool adjoining circumferential zones of the surface, and the suspended article is lowered through or past the treating device.

Apparatus constructed in accordance with this invention may comprise, as in Fig. l, a vertical framework F carrying near its upper end a heating and quenching device D and a special rotating and guiding device R above the heating and quenching device D. A shaft S, the peripheral surface of which is to be flame hardened, is suspended from above by a cable C, which is lowered or raised by a variable speed reversible motor M, the shaft being rotated by a drive collar L which is ldriven from a motor M. Each of motors M and M is preferably mounted atop the framework F, although either motor, and particularly motor M, may be mounted in other positions. Also, any other suitable power source may be substituted for either of motors M or M.

Cable C passes over a pulley P, which is preferably suspended from the ceiling of the room in which the apparatus is installed, although pulley P may be supported by a suitable column, either extending from or separate from, framework F. Of course, shaft S may be suspended and lowered at a controllable rate in any other equivalent suitable manner, many of which will suggest themselves to those skilled in the art.

As shaft S is lowered, successive circumferential surface portions thereof are heated and cooled by the heating flames and quenching jets directed thereagainst by heating and quenching device D, and as the treatment progresses the shaftl enters, and is lowered into, a well W provided for the purpose. The depth of well W is preferably such that the greatest length of shaft expected to be treated can be accommodated. The cooling medium flowing downwardly from the heating and quenching device and along shaft S is collected in a tank T, although a portion of the cooling medium will fall into well W. If desired, the framework F may be higher, or may be supported on a suitable elevating platform, in which case it will be unnecessary to provide a well.

The' framework F comprises four upright stanchions or columns I, disposed, as in Fig. 2, at the four corners of a rectangle. A plate II connects the upper end of each pair of columns l0 at the right and left, respectively. A channel or beam I2, disposed centrally of the framework, is supported by plates Ii, and motor M and rotating and guiding device R are mounted on channel I2. Motor M, as illustrated, is mounted on a bracket I3 secured vto the framework at the upper end of the right rear column I0, as in Fig. 1. Heating and quenching device D is mounted on a platform suspended from a pair of oppositely disposed plates I4, as in Figs. 1 and 2. Each of plates I4 is provided with a pair of collars I5 which surround columns yI0 and extend a sui.

cient distance upwardly and downwardly from plates I4 to prevent any opportunity for misalignment. Collars I5 rest on adjustable collars I6, by means of which the heating and quenching device may be placed in any desired vertical position. although the normally desired position of the heating and quenching device will be such that collars I5 abut the upper ends of columns I0, as in Fig. 1.

Cable C is wound on, and the Xed end thereof attached to, a drum 20 which is driven by variable speed motor M, which may be a relatively slow speed motor or may be provided with an integral speed reducer. To prevent rotation of cable C vertical alignment with upper guide bushing 4i. i

as shaft S rotates, the cable is provided with a swivel joint 2i near the opposite, or normally free, end. To permit the shaft S to be rotated by device R when the upper end of the shaft has reached the heating and quenching device, a short section or dummy shaft 22 is interposed between the upper end of shaft S and cable C. The upper end of shaft S may be drilled and tapped, as shown, so that dummy shaft 22 may be attached thereto.

Drive collar L, of rotating and guiding device R, is driven from motor M through a belt 24 which passes-around the drive collar and a pulley 25. Pulley 25 is mounted on the low-speed shaft of a speed reducer 26, which is mounted on a vertical bracket 21 secured to one side of channel I2 and the high speed shaft of which is coupled ed, and a compression spring 34,7bearing against the outer end of each plunger, presses the rollers into engagement with shaft S. The opposite end of each spring 34 bears against a plug 35 which threadedly engages the outer ends of holes 3l, and each plunger is provided with a slot 36 which cooperates with the lower end of a set screw 31 to prevent the plunger from turning within the hole. Also, the outer end of each slot 36 acts as a stop or shoulder which engages set screw 31 to limit the distance vinwardly which each plunger and roller can move when the apparatus is idle.

Block 30 is also provided on its lower side with an annular bearing groove 38 which ts over an l annular bearing ring 39, secured to a base plate 40, whicliin turn is bolted to or otherwise secured to channel I2. Since shaft S is moved downwardly, although relatively slowly, during the time that drive collar L is rotating, the vertical force exerted downwardly on the drive collar keeps block 30 pushed down on ring 39. Also, since shaft S is freely suspended, very little force is required to turn the same, and there is little tendency for drive collar L4 to be twisted out of a horizontal plane due to the pull of belt 24. It will be understood, of course, that other types of bearings, such as ball or roller bearing assemblies, ma'y be used in lieu of the bearing provided by groove 38 and ring 39.

'I'o insure maintenance of shaft S in accurate alignment, an upper guide bushing 4I is secured in a central aperture in base plate 40, in exact vertical alignment with drive collar L. The web 0f channel I2 is provided with a hole 42 through which shaft S passes. Bushing 4I is machined accurately to fit shaft S, and it is necessary to replace the bushing whenever a shaft having a different diameter is to be treated. The construction of drive collar L is such that it will accommodate a substantial variation in the diameter of shafts to be treated.

As will be evident, vertical rollers 33 rotate as the shaft S moves downwardly, but force the shaft to rotate about its vertical axis along with the drive collar L. At the same time, guide bushing 4| keeps the shaft accurately centered at a point only a short distance above the heating and quenching device D, which, as in Fig. 5, includes a plurality of blowpipe heads provided with removable tips 46, a ring-shaped quenching block 41, anda lower guide bushing 48 in exact heating names will now through the The relatively short distance between the upper and lower guide bushings obviates the possibility of 'any misalignment and consequent distortion, while the quenching .liquid flowing downwardly over the lower guide bushing minimizes the possibility of its expanding and the shaft thereby running too loosely therein.

Each of the blowpipe headsis similar in construction and is adapted to be used in treating shafts of a varietyof diameters, being provided with two rows of outlets in .which tips 46 of removable plugs 49 may :be inserted. For a shaft having a diameter as illustrated, the upper row of outlets in each head is blocked off, but in treating a shaft having a greater diameter, an appropriate number of plugs are replaced by tips. Also, any other number of heads, instead of the four heads shown in Fig. 2, may be utilized.

It will be obvious that by using separate blowpipe heads and quenching blocks, the same blowpipe heads may be used for a wide variety of sizes of metal articles, with only an occasional change in tips necessary to provide equipment for hardening new or different sizes. heads andseveral sizes of tips can be carried in stock, ya new quenching block only being made after it has been determined that a new or differs ent size is` to be hardened, the cost of new equipment as well as the time necessary to put such equipment in operation is thereby reduced.

The ring-shaped quenching block 41 is hollow and provided with an upwardly extending section 50 on the inner side thereof which permits the vquenching liquid to be directed against the heated surface portions .closely adjacent tips 46v from which the heating flames are directed clamped between upper and lower annular plates I or rings 52 and 53, respectively, the forward end of each blowpipe headv resting on the quench block and the rear end of each head resting on a shim block 54. This assembly is secured 'by bolts 55' to a base plate 56, which is provided with a central aperture in which lower-.guide bushing 48 is secured. Spacing rings I51 are placed about bolts 55 beneath the lower ring 53 toA space the assembly from 4bushing 48, and also to permit-air for secondary combustion of the heating llames to pass between lower ring-r 53 and base plate 56 and thence upwardly around the shaft, this 4current of air being induced by the flow of heated` gases upwardly from the heating flames. In addition, some air for secondary combustion of the space between the blowpipe heads.

'Each of the blowpipe heads is supplied withacombustible mixture of gases by a tube 60, and quench block 41 is supplied with a f suitable quenching liquid by tubes 6I. Also, each of the blowpipe heads is cooled by a cooling medium circulated therethrough, the cooling medium vibeingl supplied by tubes 62 and discharged through tubes 63, the latter of which are bent downwardly as shown so that the discharged cooling medium will be collected in tank T of Fig. 1.

Since blowpipe Referring now to Fig. 2, the platform upon which the heating and quenching device D is mounted comprises a pair of supporting plates 65 which are spaced apart to clear bolts 55 of Fig. 5, and to permit various sizes of assemblies which in-clude the blowpipe heads and quench block to be mounted thereon. As shown, base plate 5G is bolted to supporting plates 65.

The heating and quenching device D also includes a .pair of -blow pipes B and a pair of cooling medium headers 66. Blowpipes B are mounted on brackets 61 attached to supporting plates 65, and deliver a combustible mixture of gases to headers 68 from which tubes 60 convey the combustible mixture to heads 45 of Fig. 5. Blowpipes Bare constructed in the conventional manner, being provided with valves 69 for regulating the flow, to a mixer installed Within the body of each blowpipe, of a combustible gas, such as acetylene, and a combustion-supporting gas, such as oxygen, these gases being supplied by hoses and 'l I respectively.

Cooling medium headers 66 are supplied with a suitable cooling liquid by hoses 12, andthe cooling liquid is distributed by the headers to the quench Iblock and the blowpipe heads through tubes 6I and 62, respectively. The cooling liquid used in most instances is water, and after the liquid cools the heated surface of shaft S, or the blowpipe heads, it falls to tank T of Fig. l, as described previously. From tank T, the water is led to a sewer or other suitable place of dis-` posal by a drain pipe 15. Since some cooling liquid falls into well W, a suitable drain should also be provided at its lower end.

Should a cooling liquid other than water be used, such as oil, or a sodium hydroxide solution, drain pipe and the drain from well W may be connected with a-suitable recirculating pump and a cooling coil so that the liquid may be returned to hoses 12 for further use.

In treating an elongated cylindrical article such as shaft S, after guide bushings of the proper size are installed and the proportions of the combustible mixture adjusted so\ that the heating flames burn properly, shaft S may be placed in well W and then inserted up through the lower guide bushing. Dummy shaft 22, to which cable C has been secured and which is longer than the distance between drive collar L and lower guide bushing 48, may then be run down through the drive collar and upper guide bushing, and attached to the upper end of the shaft S. Motor M is then started in the correct direction of rotation to run shaft S upwardly until the lower end thereof is aboutto leave the lower guide bushing, in case hardening is to be started a short distance above the lower end of shaft S. Or, if hardening is to begin at the lower end of shaft S,*a second dummy shaft may be attached thereto, or the lower end of shaft S raised until just above tips 46. In the latter instance, it may prove desirable to reduce the rate of rotation of shaft S until the shaft enters the lower guide bushing, although the chamfered upper edge of guide bushing 48 will normally guide the shaft accurately into the bushing. Otherwise, the motor M is started to rotate the shaft S at the desired speed, such as between and 100 R. P. M., depending upon the diameter.

Next, the oxygen and acetylene are turned on, and the heating flames ignited by a pilot light or small lighting blowpipe provided for the purpose. At the same time, the ow of quenching and cooling medium is started, and motor M or starts to flow ahead/motor M may be accel-.

. erated to provide the normal rate oi.' traverse,

usually between 4 and 10 inches per minute. Aften a short distance has beenv traversed, the shaft `Wil1 be in the position of Fig. 1. y

In case the upper end of the surface to be hardened coincides with the end of the shaft, the relative rate of traverse is increased just before'the end of the shaft is reached to prevent overheating the surface at the end, which otherwise might occur due to the lesser amount of heat conducted from the -end of the shaft. As soon as the heating ames reach the top of the shaft, or the top of the surface portion to be hardened. they are turned off, but the quenching liquid is not turned off until the uppermost heated zone has been quenched. When the surface portion to be hardened terminates below the upper end of the shaft, it may be desirable to continue application of the quenching jets to a point above the last zone directly heated, in order to minimize the possibility of residual heat creeping back down the shaft to reheat hardened surface portions and thereby reduce, though not destroy, the hardness imparted to the last zone or zones hardened.

As soon as the upper end of shaft S is reached, the shaft will be in a position in which it can be replaced by a second shaft to be treated. To

accomplish this, it is necessary only to disconnect shaft S from dummyshaft 22, lift shaft S from the well W, insert the second shaft into well W, and then attach the second shaft to dummy shaft 22. The operation then proceeds as just described.

It will be understood that the apparatus, although described with respect to hardening outer surfaces of shafts and the like, may be modified for hardening the inner surfaces of tubes or the like, such as by utilizing a heating and quenching ldevice adapted to direct heating flames and quenching jets outwardly instead of inwardly. It will be further understood that the apparatus of this invention is not limited to hardening alone, but may be used in welding,`cutting, desurfacing, and the like-in fact, any procedure in which it is desired to heat successive portions of a cylindrical surface of an elongated metal article While the article is rotating. It will also be understood that other changes, in the apparatus may be made which will not depart from the spirit and scope of this invention, as defined in the appended claims.

What is claimed is:

l. Apparatus for treating a cylindrical surface of a metal article comprising means for suspend-Y ing said article from a point at or adjacent the upper end thereof so that the axis of said surface is disposed substantially vertically and so that said article is relatively freely rotatable ,about said axis; a device for treating a limited 'vertical portion of said surface; a guiding bushing disposed above and a guiding bushing disposed below and closely adjacent said device, for maintaining ,said article in substantially exact alignment during treatment; means for rotating said article about said axis` said rotating means comprising a rotatable drive collar provided with a plurality of rollers each mounted for rotation about a horizontal axis and engaging said article at spaced circumferential points above said treating device; and means for effecting a relative vertical movement between said article and said treating device so as to treat successive vertical portions of said surface.

2. Apparatus for treating a cylindrical surface of a metal article comprising means for suspending said article from a point at or adjacent the upper end thereof so that the axis of said surface is disposed substantially vertically and so that said article is relatively freely rotatable about said axis; a device for treating a limited vertical portion of said surface; a guiding bushing disposed above said device and a guiding bushing disposed below said device, for maintaining said article in substantially exact alignment duringtreatment; a rotatable drive collar for rotating said article about said axis, said drive collar being mounted above said treating device and being provided with a plurality of rollers, each mounted for rotation about a horizontal axis and vertical movement between said article and said treating device so as to treat successive ver-tical portions of said surface.

3. Apparatus for hardening a cylindrical surface of an elongated metal article comprising an upright framework; a heating and quenching device mounted on said framework, said heating and quenching device being adapted to direct a plurality of high temperature heating flames against a circumferential zone of said surface and a plurality of quenching liquid jets against an adjoining circumferential Zone beneath the zone against which said heating flames are d1- rected; means for supporting said heating and quenching device near the upper end of said framework; a lower guide bushing for said article and mounted beneath and in vertical alignment with said heating and quenching device; an upper guide bushing for said article and mounted above said heating and quenching device in direct vertical alignment with said first guide bushing; a drive collar mounted for rotation about a vertical axis and disposed adjacent and in vertical alignment with said upper guide bushing, said drive collar being adapted to rotate said article about the axis of said cylindrical surface; means for rotating said drive collar; and means for suspending said article from the upper end thereof and for lowering said article so as to heat and quench successive circumferential zones of said article While rotating.

4. Apparatus for hardening a cylindrical sur- -face of an elongated metal article as dehned in claim 3, in which said drive collar includes an annular block having a plurality of circumferentially spaced plungers movable horizontally inwardly towards and outwardly from the axis of rotation of said collar, a roller mounted for rotation about a horizontal axis at the inner end of each of said plungers, and la spring normally urging ea'ch of said plungers inwardly.

5. Apparatus for hardening a cylindrical surface of an elongated metal article, as defined in claim 3, in which said suspending and lowering means includes a cable operatively connected at one end with an adjustable power source for effecting movementof said cable in the direction of its length, a pulley supported above said drive collar and over which said cable passes, a dummy article connected at its lower end with the article to be treated and at its upper end with the normally free end of said cable, and a swivel joint interposed in said cable above said dummy article, said swivel joint being adapted to permit rotation of said article by said drive collar while said article is being lowered by said cable.

6. In apparatus for hardening a surface of a metal article which includes a heating head provided with a row of outlets substantially parallel to one side thereof for directing high temperature heating flames against said surface, a quenching device comprising a block abutting against the side of said heating head adjacent said row of outlets with a section thereof extending past said heating head and toward said outlets, a plurality of outlets in said section for directing jets of quenching uid against said surface, and a cooling huid supply passage formed in said blockand connecting with said cooling uid outlets.

7. In apparatus for hardening a surface of a metal article as dened in claim 6, a quenching device in said cooling fluid outlets are inclined at an angle away from said heating outlets.

8. Apparatus for hardening a surface of a metal article comprising a blowpipe head provided with a row of holes in the face thereof and adapted to receive tips provided with outlets for directing high temperature heating dames against said surface; means for supplying said head with a combustible mixture of gases, said head being provided with means for conveying such combustible mixtures of gases to said holes and tips; a quenching device disposed closely adjacent said head and having a section extending beyond the face of said head and to a point closely adjacent the discharge ends of said tips, and outlets in said extending section, disposed substantially parallel to said row of tips, for discharging a cooling medium against 'said surface; means for supplying said quenching device with a. cooling fluid, said device being provided with a passage for conducting such cooling uid to said outlets; means for supporting said article l ROMAN E.' ARNoLDY.

CERTIFICATE OF CORRECTION.

Patent No. 2,510,581. February 9, 1915.

` ROMAN F. ARNOLDY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page l, second column, line 18, strike out "must be provided" page 5, second column, line 12, for "of" second occurrence, read or; page 24., second column, line 51;, for "heat" read' treat 3 page 5, second column, line 55, claim Y, after in insert --which; and that the said Letters Patent should'be read with this correction therein that the same me)r conform to the record of the case in the Patent Office.

signed and sealed this 16th day of March, A. D. 19M.

Y Henry Van Arsdale, (Seal) Acting Commissioner of' Patents.

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