Method and apparatus for producing a decorative effect on stainless steel and other surface

Dec. 8,..1970 l. l. duncan 3,545,996

METHOD AND APPARATUS FOR PRODUCING-A DECORATIVE EFFECT .ON.STAINLESS STEEL AND OTHER SURFACE

Original. Filed Dec. 20, .1963 7 Sheets-Sheet 1

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LEON L. DUNCAN

INVENTOR ^Dec*⁸’¹⁸⁷£ L. L. DUNCAN 3,545,996

METHOD AND APPARATUS FOR PRODUCING A DECORATIVE EFFECT „ . . , . ON STAINLESS STEEL AND OTHER SURFACE

Original Filed Dec. 20, 1963 ₇ Sheets-Sheet 2

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Dec. 8, 1970 ll. duncan 3,545,996

METHOD AND APPARATUS FOR PRODUCING A DECORATIVE EFFECT ON STAINLESS STEEL AND OTHER SURFACE

Original Filed Dec. 20, 1963 7 Sheets-Slioot 3

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Dec. 8, 1970 l. l. duncan 3,545,996

METHOD AND APPARATUS FOR PRODUCING A DECORATIVE EFFECT ON STAINLESS STEEL AND OTHER SURFACE

Original Filed Dec. 20, 1963 7 Sheets-Sheet 4

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INVENTOR

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Dec. 8, 1970 l.l. duncan 3,545,996

METHOD AND APPARATUS FOR PRODUCING A DECORATIVE EFFECT ON

Original Filed Dec. 20,

STAINLESS STEEL AND OTHER SURFACE γ Sheets-Sheet' 5

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3,545,996

EFFECT

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ON Original Filed Dec. 20,

Dec. 8, 1970 l. l. duncan

METHOD AND APPARATUS FOR PRODUCING A DECORATIVE STAINLESS STEEL AND OTHER SURFACE 1963 ₇

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INVENTOR

LEON L. DUNCAN

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3,545,996

EFFECT

Sheets-Sheet Ί

Dec. 8, 1970

METHOD AND

Original Filed Dec.

L. L. DUNCAN

APPARATUS FOR PRODUCING A DECORATIVE ON STAINLESS STEEL AND OTHER SURFACE

20, 1963 ₇

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INVENTOR

LEON L. DUNCAN

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United States Patent Office

3,545,996

Patented Dec. 8, 1970

3,545,996

METHOD AND APPARATUS FOR PRODUCING A DECORATIVE EFFECT ON STAINLESS STEEL AND OTHER SURFACE

Leon L. Duncan, Washington, Mo., assignor to Zero Manufacturing Company, Washington, Mo., a company of Missouri

Continuation of application Ser. No. 332,230, Dec. 20, 1963. This application Feb. 25, 1969, Ser. No. 804,364 Int. Cl. B44d 1/94; B44c 1/06; B74c 1/04

U.S. CI. 117—8 7 Claims

ABSTRACT OF THE DISCLOSURE

A method of peening a metallic surface with microscopic glass beads in a partial vacuum wherein the beads are removed from the surface undergoing peening by introducing an air stream on one side of the surface and exhausting it on the other side together with the spent beads and debris. Placing a plurality of units to carry out the foregoing method on a crankshaft and rotating same on the metallic surface which is moving relative to the crankshaft. Spacing a stencil above the metallic surface, peening the surface through the stencil while at the same time removing spent peening material and debris by means of an air stream flowing between the metallic surface and the stencil. Plating the surface either before or after peening same with microscopic glass beads whereby part of the plating may be removed. Introducing embedding materials with the peening materials so that the embedding materials are peened into the surface being treated.

This application is a continuation of my application Ser. No. 332,230 filed Dec. 20, 1963, and now abandoned.

This invention relates to a process for producing a decorative finish on stainless steel and other surfaces by the peening of such surfaces with microscopic spherical bodies through a stencil pattern and effectively removing such bodies and other waste debris from the working area without contaminating the atmosphere.

The invention also relates to the inclusion of embedding material along with the peening material which is embedded into the surface to be finished at the same time the aforesaid finish is produced.

The invention additionally relates to apparatus utilized in such methods.

At the present time, stainless steel and other metallic surfaces are frequently used for counters, walls, and other structural surfaces which present substantial surface areas. It is often desirable to ornament or imprint these areas in order to improve their appearance, for identification purposes, and so as to reduce reflection, glare and the like. Ideally, such finishing should not change the strength and corrosion characteristics of the metal, and also should not constitute such an expense whereby the sales prices of the metallic sheets involved have to be raised materially in view of the cost of the finishing process. However, with the present general practices, surfaces are frequently finished by abrasive means which remove a portion of the metal and at the same time increase the selling price of the metal appreciably. For example, stainless steel surfaces with decorative effects produced by present methods frequently have a selling price more than one-half again as great as similar articles without the decorative effects. In contrast, if the stainless steel is treated in accordance with the method of this invention, pleasing finishing effects may be produced on stainless steel without significantly increasing the price to the user. At the same time, little or no material is removed from the surface of the stainless steel, and, in fact, such surface is somewhat strengthened by the peening effect imparted to the surface which is subjected to the finishing operation. Moreover, if embedding material is used concurrently with the peening material, a plating effect is produced wherein the embedded is hammered into the finished areas.

Accordingly, it is an object of this invention to provide a method which produces a decorative finish of stainless steel and other surfaces which is inexpensive, effective, and which does not remove metal from the surface so treated.

It is a further object of this invention to produce such decorative effect by the placing of a stencil over the surface to be decorated and directing a fluid stream at such surfaces with treating material introduced therein which impinges upon the exposed portions of the surface through the stencil; the same to be carried out in a closed housing under a partial vacuum whereby expended treating material and debris are drawn from the area which has been treated without contaminating the atmosphere.

It is still a further object of this invention to carry out such a process by means of an endless stencil which, together with the surface to be treated, moves under the fluid stream containing a treating material.

It is a yet further object of this inevntion to entrain in the aforesaid fluid stream an embedding material which impinges upon the surface together with the treating material and is bonded thereto.

Another object of the invention is to place a plurality of housings together with a plurality of stencil means successively over a surface to be decorated whereby various types of embedding materials and intensities of peening are imparted to the surface involved.

An additional object is to provide an apparatus adapted to produce a line or single pattern of peened finish on a surface, whereby the former is produced by moving said surface relative to said apparatus and the latter is produced when the surface involved and apparatus are maintained stationary relative to each other.

A further object is the provision of apparatus of the type described wherein the fluid flow or the treating material flow, or both, are permitted only when the apparatus is in contact with the surface to be treated and are cut off when such apparatus is raised from said surface.

Other objects, adaptabilities, and capabilities will appear as the description progresses, reference being had to the accompanying drawings, in which:

FIG. 1 is a schematic drawing illustrating the method and apparatus of the invention;

FIG. 2 is a side elevation in partial section showing apparatus in accordance with the invention in operation with compressed air and treating material passageways connected to channels in a hollow housing;

FIG. 3 is a plan view of the apparatus shown in FIG. 2;

FIG. 4 is a detail of the stencil means utilized in the apparatus shown in FIGS. 2 and 3;

FIG. 5 is a detailed perspective of the sealing or bearing means into which the stencil means shown in FIG. 4 fits;

FIG. 6 is a side elevation, in partial section, illustrating a modified arrangement of apparatus similar to that shown in FIG. 2;

FIG. 7 is a side elevation of the combination of a plurality of devices as shown in FIG. 6, together with an endless stencil means adapted to roll between such devices and the surface to be finished;

FIG. 8 is a plan view of the combination shown in FIG. 7 with the upper portion of the stencil means and other portions of the apparatus broken away;

FIG. 9 is a side elevation in partial section illustrating

3,545,996 a further modified arrangement of apparatus similar to that shown in FIG. 2;

FIG. 10 is a front elevation in partial section illustrating the modified arrangement shown in FIG. 9;

FIG. 11 shows a stencil roller which encircles apparatus such as shown in FIGS. 9 and 10;

FIG. 12 is a plan view and

FIG. 13 is a front elevation showing apparatus of the type disclosed in FIG. 2 being utilized to produce a curved line on a surface moving thereunder;

FIG. 14 is a schematic drawing showing a plurality of treating means in accordance with the invention used to treat successively a single surface;

FIG. 15 shows a method to secure a member such as shown in FIGS. 7 and 8 in a fixed position over metal which travels beneath such member;

FIG. 16 shows a modified arrangement wherein the stencil means is spaced from the surface to be treated;

FIG. 17 is a plan view partially broken away of the stencil means shown in FIG. 16;

FIG. 18 is a front elevation view in section showing the-recovery means of the treating material utilizing the apparatus shown in FIGS. 16 and 17;

FIG. 19 is a side elevational view of the apparatus shown in FIG. 18;

FIG. 20 is a schematic view of a further means of providing a stencil in combination with the apparatus and method of the invention;

FIG. 21 is a side elevation illustrating a still further modification in accordance with the invention;

FIG. 22 is a plan view wherein a plurality of devices such as shown in FIG. 6 rotate on a crank shaft;

FIG. 23 is a side elevational view of the apparatus shown in FIG. 22;

FIG. 24 shows a combination of means such as shown in FIGS. 7 and 8 carried on a portable device;

FIG. 25 is a section in magnification of a plated surface subjected to the process of the invention;

FIG. 26 is similar to FIG. 25 showing the same section following removal of metal by acid;

FIG. 27 is a cross section in side elevation of a modification of apparatus utilized in the invention; and

FIG. 28 is a front elevation in cross section of the apparatus shown in FIG. 27.

Referring now to FIG. 1, a sheet of material 30, such as stainless steel, is introduced onto an endless support means such as belt 31 and is carried thereon in the direction of arrow 32 first under a polisher 34 and subsequently under a pair of surface treating means 35 and 36.

From FIG. 2, it is to be seen that surface treating means or unit 35 comprises a conduit 38 which leads a fluid under pressure, usually air, into the hollow housing 37, wherein treating material from passageway 40 is entrained into the fluid stream from conduit 38. At the bottom of the housing 37 there is received a graphite sealing means comprising a shoe 41 which carries stencil means insert 42. The insert 42 has a funnel-shaped perforation 44. The insert 52 together with the shoe 41 contact the working surface 45 of sheet 30 to form within housing 37 a hermetically sealed chamber 46. In the vicinity of the working surface 45 through the perforation 44, a passageway 47 is provided which leads to a vacuum source such as vacuum pump 50 or other suitable means for withdrawing the spent fluid and treating material. An opening 51 may be provided in the housing 37 to produce a cross current of air and turbulence in the vicinity of the perforation 44. From FIG. 2 it will be appreciated that a stream of fluid with entrained treating material strikes only that portion of the working surface 45 exposed through perforation 44 in the stencil means insert 42 and that, thereafter, the spent treating material and excess fluid is drawn through passageway 47 aided by turbulence due to air entering opening 51. Referring again to FIG. 1, it will also be appreciated that when unit 35 is held stationary with the sheet 30 moving beneath it, a peened line is imprinted on the surface of the sheet 30.

The surface treating means or unit 36 contains a plurality of treating elements 60 of the type shown in FIG. 6. Such elements include a housing 61 into which is conducted a fluid stream through a conduit 62. Treating material is introduced through passageway 64 into such stream which is directed toward working surface 65 through a funnel-shaped nozzle 66. Sealing means comprising a graphite shoe 67 is slidably received in the lower portion of the housing 60 and, as shown in the apparatus of FIG. 2, there is a stencil insert 70 which is carried by this shoe 67. An opening 71 to the atmosphere admits air to cause a certain amount of turbulence within the housing 60 and spent air, treating material and other debris are carried away through passageway 72 which connects with the vacuum pump 50 or other appropriate withdrawing means. In the lower part of the housing 60, a circular projection 74 has threaded to it a ring portion 75 to provide an annular groove 76. The shoe 67 is received in such annular groove 76 and held in place there by a bushing 77 which supports flange 80 of shoe 67. A closed helical compression spring 81 urges the shoe 67 away from the housing 60. The circular extension 74 of the housing 60 has a pair of openings 82 and 84 each of which receives actuation means comprising flexible wires 85 and 86. The wire 85 is carried by a channel 87, secured to the housing 60, to a lever 88 which controls a valve 90 in the conduit 62. Similarly, the wire 86 is carried by a channel 91 to control a valve 92 in the passageway 64. It will be appreciated that when the shoe 67 moves upwardly relative to the housing 60 the valves 90 and 92 are opened, whereas when the shoe 67 moves downwardly with respect to the housing 60 such valves 90 and 92 are closed. Accordingly, the element 60 may be turned on and off depending upon whether it is placed in operating condition or not. While FIG. 6 shows a sealing insert 70, such insert may be dispensed with when endless stencil means such as shown in FIGS. 7 and 8 are employed with such elements. FIG. 6 shows the shoe 67 extended for the purposes of clarity. However, it will be appreciated that the weight of unit 60 would normally be sufficient to compress spring 81.

Referring now to FIGS. 7 and 8, it will be seen that the stencil comprises a belt 100 which has a plurality of predetermined perforations 101. The belt 100 is carried around three sets of rollers 102,104, and 105. Such rollers are supported or held in position by a pair of inverted T members 106 which are held together by a plurality of similar axles 107 received through bores extending through the longitudinal center lines of the rollers 102, 104 and 105. Bores 110 and 111 in rollers 104 and 105, respectively, are larger in internal diameter than the overall diameter of the axles 107 received therein. Such circumstance facilitates the insertion of the belt 100 on such rollers, permits the use of the unit on somewhat uneven surfaces, and allows the automatic closing of the various elements 60 when the unit is raised relative to the surface which is being treated. The T members 106 also carry: vacuum manifolds 112 which connect with the vacuum pump 50α, fluid manifolds 114 which connect with a fluid pressure source such as compressor 115, and a material feed manifold 116 which connects with a treating material supply source such as hopper 117. The vacuum manifolds 112 connect with the passageways 72 of units 60. In like manner, the manifolds 114 and 116 connect with the conduit 62 and the passageway 64 of each unit 60. Ears 120 of each unit 60 are carried by a plurality of rods 121 which in turn are supported by the T members 106. In operation, it will be appreciated that the belt 100 moves continuously relative to the workpiece 30 and the units 60 through the perforations 101 in belt 100 produce a pattern as determined by the position of the perforations 101 on the sheet 30.

FIGS. 9 and 10 show a distinctive unit 130 wherein

3,545, a housing 131 has a plurality of fluid supply conduits 132 entering through the upper part thereof. Material is entrained through passageway 134 which leads into the conduit 132 just above spreading means 135. A fluid stream through conduit 132 with treating material from passageway 134 is spread into a fan shape by the spreading means ⁸135 following which it impinges upon the working surface 136. Subsequently, the spent treating material is scavenged through the passageway 137 which leads to a subatmospheric source such as vacuum pump 50 and a scavenging effect is assisted by turbulence introduced into the housing 131 by an opening 140 to the atmosphere. The housing 131 is received by a shoe 141 which in turn carries an insert 142 with a groove 144 opening to surface 136. The insert 142 thus has a continuous groove portion 144 which permits the fluid stream with treating material to impinge on the surface 136 following which it is carried away through the passageway 137 which, as is to be noted from FIGS. 9 and 10, is in the immediate vicinity. A pair of straps 145 which are connected to the side of ₂₀the housing 131 carry rollers 146 in front of and behind the housing 131.

The unit 130 may be incorporated in a system such as shown in FIGS. 7 and 8 in place of units 60 or in a further system as shown in FIG. 11, wherein a cylin- 95 drically shaped endless member 150 with predetermined perforations such as, for example, 101 shown on belt 100 is carried by rollers 151, attached to a hub member 152. A bearing 154 engages the hub 152 and is rotatable about the latter. Extending outwardly from the circular bearing 39 member 154 are a plurality of spokes 155 which are composed of resilient wire. These spokes each connect with a resilient rim 156 which in turn aids in supporting the endless member 150 and confining it on the rollers 151. The hub member 152 also has secured to it lines 160, 161, 33 and 162 which lead to a treating material supply, to a compressed fluid source, and to a subatmospheric source, respectively, from passageway 134, conduit 132, and passageway 137, respectively. When surface 136 is moved relative to the unit 130 within the endless member 150, 40 the latter member 150, together with the rims 156, spokes 155, and bearing members 154, rotates around the shoe 141 and insert 142 whereby the pattern of the endless member 150 is imprinted on the surface 136 by the peening effect produced by the fluid stream together with the treating material impinging upon the surface 136 beneath unit 130.

In FIGS. 12 and 13 a pair of units 35 are carried side by side in a framework 170 transversely disposed above a moving sheet of material 171. The framework 170 is 59 movable transversely in bearings 172 and 174 on base member 175, which member also supports the belt 178 which carries the sheet having the working surface 171. Also carried by the base structure 175 is a cam member 176 which is rotated through a belt member 177 from 55 a motor 180 via pulleys 181 and shaft 182. A helical compression spring 184 urges the framework 170 into contact with the cam member 176. As the cam member 176 is rotated, the framework 170 slides transversely in reciprocating motion relative to the moving of the surface 171 θο to produce, by the action of units 35, curved lines or waves 185. It will be understood that by using various types of cams 176 an endless variety of waves 185 may be produced.

FIG. 14 shows a schematic representation wherein a 65 plurality of units 36 with different belt means 100 are connected in tandem to produce unusual effects. The units are designated in FIG. 14 as 36α, 366, and 36c. They are connected with pulley means 186 and 187 to insure an equal rotation. Very unusual effects may be produced 70 by this method in that the intensity of the peening may be varied or differing types of embedding substances may be added to the treating material to give areas of distinctive color qualities. In this connection, attention is invited to the patent to N. C. Parrish, No. 2,618,572 of 75

996

Nov. 18, 1962, wherein the plating of one metal, titanium, or other surfaces is taught by means of shot peening and impact plating. In the present invention, it has been found that a number of materials which are generically described herein as “embedding substances” will, when mixed together with the treating material, embed themselves on the treated surface and a firm bond is established in peening of such material by the treating material. The latter preferably constitutes microscopic spherical bodies composed of glass or like substances. Embedding substances found to have utility in the method of the invention comprise aluminum, copper, silver, gold, bronze, lead, titanium, nickel, tin, and zinc. It is, however, considered that a number of other substances having the same general characteristics will be found suitable for this process. The physical characteristics of embedding substances which are suitable in the present method are the capacity to be bonded with the surface treated by impinging thereon at a high velocity or by the peening effect of the microscopic glass spherical bodies or by both.

FIG. 15 shows a way whereby a unit such as unit 36 may be secured to the supporting structure of the endless member which carries the sheets 30. Accordingly, it will be noted that a pair of upwardly extending parallel links 190 are rotatably mounted on extensions 191 on the supporting structure 193. At their upper aspects, the links 190 engage the two outer axles 107, whereby the extensions 191 and the axles 107 form the apexes of a parallelogram. An extension spring 192 tends to rotate the links 190 in a counterclockwise direction as seen in FIG. 15, whereas the movement of the workpiece 30 tends to move said links in a clockwise direction. A stop member 193a on structure 193 limits the aforesaid counterclockwise movement. With such an arrangement, friction of the workpiece 30 on the belt 100 holds the unit 36 in a gripping engagement as long as the workpiece 30 is moving. However, if for any reason the workpiece 30' should be stopped, the links 190 will move in a counterclockwise direction and, as described previously, with the lifting of the units 60 the peening operation is automatically ceased. This type of connection is advantageous wherein it is desired to maintain a more or less constant peening rate. However, it will be appreciated, that the units 35 and 36 may be maintained stationary relative to the structure 193 by any of a number of contrivances which will occur to one skilled in the art.

FIG. 16 relates to modification wherein a spaced stencil means 194 is placed over a sheet or slab 195 of the material to be treated. A unit 196 similar to the units previously shown, particularly that shown in FIGS. 9 and 10, is placed over the stencil means 194. However, in the modification 196, an opening such as opening 140 is omitted, and a fluid stream through the conduit 132α is more nearly perpendicular to the stencil means 194. From FIG. 16, it will be appreciated that a certain amount of the treating material in the fluid stream from conduit 132α will impinge upon the stencil means 194 to be carried away through the exhaust passageway 137α. To carry away the treating material and waste debris from the space 197 between the workpiece 195 and the stencil means 194 there are provided (FIGS. 17, 18) a pair of parallel jets from further fluid conduits 200 and 201. These are spaced under but to either side of where fluid from conduit 132 impinges on sheet 195. The material is thus entrained and led or blown to a chute 202 wherein it falls to the bottom and is entrained by a further jet from conduit 204 into a flexible line 205 wherein it is carried to a withdrawing source such as vacuum pump 50 shown in FIG. 1. By using in succession different stencil means 194 or a single sheet 195, and where desired, by entraining embedding substances into the passageway 134α together with the treating material, novel and unique decorative effects are produced upon the surface of the sheet 195 of both ornamental and utility value.

3,545,996

In FIG. 20, a schematic method of employing the unit 130 as shown in FIGS. 9 and 10 is set forth. Accordingly, it will be noted that the workpiece 210 has fed to it a sheet of stencil roll 211 which is rolled together with the workpiece 210 by its movement on endless member 212. The unit 130 is maintained in a stationary position relative to the movement of the workpiece 210. The stencil roll 211 has a pattern already cut into it and this pattern is peened by the unit 130 onto the surface of the workpiece 210 as the workpiece together with the sheet from roll 211 pass thereunder. If desired, the stencil from roll 211 may be adhesive on its underside and kept on work sheet 211 for shipping and tire like to protect the surface just polished by means of the polisher 34. A cutting means 214 is provided to cut the sheet from roll 211 at the end of the workpiece. The cutting mechanism 214 may be operated automatically or manually as desired.

FIG. 21 discloses unit 130 which carries a feed stencil roll 215 and a takeup stencil roll 216 on supports 217 and 218, respectively. A friction pulley belt 220 connects the axles of the roller 146 and of the takeup roll 216 whereby the takeup roller will continually take up the slack in the sheet being rolled beneath the unit 130 from the stencil roll 215. This arrangement is particularly advantageous wherein instead of using the same design over again as is the case of the apparatus shown in FIGS. 7, 8, and 11, a distinctive non-repeating pattern is desired.

FIGS. 22 and 23 disclose a pair of identical parallel crankshafts 220 disposed transversely to a moving work sheet 221. Six units 60 as shown in FIG. 6 are arranged with the ears 120 grasping the crank pins 222 between the crankshafts 220. In accordance with this arrangement, when the workpiece 221 is moved under the units 60, carried on the crankshafts 220, said crankshafts will be rotated by the frictional contact of the units 60 with the workpiece 221. As rotation occurs, the units 60 will in sequence be actuated to produce a pattern on workpiece 221.

It will be appreciated that for one reason or another, it may be desirable to maintain the workpiece stationary and to move the stencil unit relative to same. Accordingly, FIG. 24 discloses a portable apparatus wherein a unit 36 may be rolled over a workpiece 224. In such event the fluid source 225, the material feed 226 and a withdrawal means 227 may be carried on the portable structure 230 whereby the unit 36 may be conveniently rolled over the workpiece 224, treating same as heretofore described.

Interesting effects may be achieved by plating, either before or after the peening operation, the material to.be peened. For example, FIG. 25 shows a magnified section of copper plated on aluminum to a thickness of .002. It will be noted that the peening creates thickened rims 234 of copper and craters 232. The aluminum may be exposed in the pits of the craters to give a contrasting effect. This effect may be heightened by dissolving a portion of the copper in an acid bath to afford a surface such as shown in FIG. 26 wherein only copper may be found at the rim areas 234.

Where the plating is accomplished following the peening treatment, the surface tends to retain its dull satin-like appearance, particularly with thin gage plating, and the bond of the plating to the surface is substantially improved.

FIGS. 27 and 28 are directed to a distinctive type of peening unit 240, which has certain advantages in the process of the invention. In the unit 240, the peening material is already entrained in a fluid stream introduced through conduit 241 at a high velocity. The treating material is normally microscopic spherical bodies of glass. Through conduit 242, a further stream of fluid is introduced which has less velocity than that of the stream of conduit 241 and may have embedding material contained therein, preferably such material being in individual bodies so shaped as to have a mass-to-surface ratio less than that of the treating material. Extending from the sides of the unit are conduits 244 which connect within the unit to a slotted pipe 245. At the bottom of the unit 240 is a shoe 246 and a shoe insert 247. The front portion 250 of the unit 240 spirals around the pipe 245. In operation, the stream containing treating material introduced through conduit 241 meets the slower stream having embedding material introduced through conduit 242. Both materials impinge on surface 251 and the embedding material is thereby hammered into the surface. Spent material having little velocity will be either withdrawn through pipe 245 or enter a whirlpool-like movement around pipe 245 to be used a second time as a treating or embedding material.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom; the modifications will be obvious to those skilled in the art.