US2631536A - Decorating stamp - Google Patents

Description

March 17, 1953 R. J. RILEY 2,631,536

' DECORATING STAMP Filed Dec. 13, 1948 INVENTOR. o RAY d. RILEY Patented Mar. 17, 1953 UNITED STATES TENT OFFICE DECORATING STAMP Pennsylvania Application December 13, 1948, Serial No. 64,973

(Cl. lOl- 376) 2 Claims.

operated machine of this character is disclosed in my co-pending application, Serial No. 8,914, filed February 17, 1948, to which attention is invited. In this machine the ware is carried .upon a rotatable chuck, and the stamp which is curved or segmental, receives a film of ink, engages and rotates the ware frictionally and 'imprints the design upon the ware surface.

Usually the ware includes a handle, and the decorative indicia is applied, starting at a point jclosely adjacent the handle, extending around the ware, and terminating uniformly at a point closely adjacent the opposite side of the handle.

Thus a continuous band of decoration is applied around the ware except for that portion which is occupied by the handle.

In order to produce clear sharp impressions it is evident that there must be no relative motion or skidding between the stamp and the ware surface. For this purposethe printing face of the stamp is backed by a resilient foundation which makes the stamp deformable to the contour of the ware. The stamp presses against -the ware with considerable pressure so that it conforms to the contour of the ware and rmly embraces it in frictional engagement. If the ware pieces were regular or cylindrical in profile, the application of uniform sharp decorations would be comparatively simple, but most of the ware so decorated is irregular in profile. Tea vcups for example, usually have a small base and are outwardly toward the lip. In most cases the decorative indicia is applied to this flared portion.

The principal object of the invention has been to provide a stamp so constructed `that the dis- V tortion of its printing face is controlled in a manner to provide a substantially uniform pressure against an irregular ware profile to produce a clear, sharp decorative band around the ware. This` has'been achieved by building up a series of laminations of graduated resiliency so arl ranged that the softer or more resilient sections -occupy the area where the greatest defiection takesrplace, suchv as in the flared portionof ware pieces. By virtue of its softness, that portion of the stamp backing which is subjected to the greatest deformation, develops substantially no greater pressure than the portion which is subjected to the least deformation.

A further object has been to provide a resilient stamp backing in which lateral expansion or bulging is controlled to prevent loss of force sidewise, thereby to direct the full compressive force to the ware surface and also to protect the laminations from deterioration due to contact with cleaning fluid, which is employedat intervals to clean the stamp surface. Lateral deflection is regulated by a strip or lamination of pliable Vmaterial having limited elasticity, residing intermediate of the deformable layers to tie them together laterally. A protective lamination is located immediately beneath theV stamp strip to absorb cleaning fluid and protect from deterioration the deformable layers.

In the drawings:

Figure 1 is a generally fragmentary view illustrating the improved printing shoe mounted upon a rotating drum in operation upon a ware piece carried byV a rotatable chuck.

Figure 2 is a face view of the printing stamp taken along line 2 2, Figure 1.

Figure 3 is a sectional view taken along line 3 3, Figure 1, illustrating on an enlarged scale, the laminated construction of the shoe.

Figure 4 is a sectional view taken on line 4 4 illustrating the distortion of the laminated stamp foundation, conforming to the irregular profile of the ware.

Figure 5 is a fragmentary view illustrating the distortion of the shoe at the large diameter of the ware, as viewed along line 5 5, Figure 4.

Generally described with reference to Figure 1, the stamp unit indicated generally at lo, is secured by means of screws II to a printing wheel or drum I2. The ware piece I3, in the present instance, constitutes a tea cup having a small base and flaring outwardly toward the lip. The cup includes a handle I4 and the printing shoe I0 corresponds to the developed length of the circumference of the cup. In operation, the printing machine is arranged to position theV handle I4 toward the drum I2 so that the leading edge I5 of the curved or arcuate stamp contacts the cup Vclosely adjacent the handle. The cup is mounted upon a rotary chuck (not shown) and'is frictionally engaged and rotated in unison with the stamp as the stamp passes through its 'orbit in contact with thecup.` A'Ihetrailing edge IS of the stamp ends the decoration closely adjacent the opposite side of the handle I4 at completion of the operation. As illustrated in Figure 4, the laminated foundation of the stamp, indicated at I7, permits the printing surface to deflect and closely embrace the curved profile of the ware piece.

Described in greater detail, the printing shoe comprises a rigid base member 20 of arcuate or curved shape as viewed from the side, conforming to the radius f the printing drum I2. Base member 20 preferably is formed of metal such as aluminum and includes tapped holes to receive the mounting screws Il which extend through the rim 2l of the printing drum as shown in Figure l. Upon base member 2li is adhesively secured strips of deformable material such as foam rubber (Figures 3 and 4). These strips are located side by side, preferably cemented together, strip 22 being formed of material which is softer than the strip 23 to permit a substantial degree of compression to compensate for the large diameter or rim portion of the Ware. The adjacent strip 23 constitutes a section of greater firmness so as to provide approximately the same pressure as strip 22 although it is compressed a lesser degree due to the decreased diameter of the ware in the area of this strip. It has been found in practice that foam rubber or synthetic rubber, developing a force of approximately sixty pounds per inch under compression, and a strip 23 developing approximately twice this force, constitutes a satisfactory combination under the service conditions illustrated. It will be noted however that the characteristics of the materials may be Varied according to the ware contour and particular kind of printing operation involved.

The next layer of the foundation constitutes a strip 24 of rubber or other pliable material having rubber-like characteristics. This strip is ad'- hesively secured to the strips 22 and 23 and is readily deformable as shown in Figure s, but offers. controlled resistance to stretching laterally. Strip 24 therefore regulates lateral expansion, prevents undue loss of force and serves to hold the foundation in shape under deformation. In other words, due to displacement the relatively soft materials making up the stamp foundation would bulge outwardly under compression withY a resulting loss of compression, but by inserting the strip 24 this. tendency is controlled, thereby permitting more accurate regulation of the pressure developed in compressing the stamp against the ware.

The next lamination 25 is in the form of a full width strip approximately the same thickness as strips 22 and 23 and having approximately the same compressive force as strip 22. This strip provides an equalizer to distribute more uniformly the differential pressures developed by the strips 22 and 23. Since strip 23 develops approximately twice the pressure of strip 22, and since the Ware prole curves gradually to a smaller diameter, lamination 25 absorbs and compensates for the pressure differential to cause substantially uniform stamp pressure.

Upon strip 25 is placed a strip or lamination 26 formed of a material which is resistant to cleaning uids. Such iiuids are applied at intervals to the stamp face to remove gummy deposits which tend to reduce clarity and detract from the quality of the work. Strip `26 preferably is of a spongy material toabsorb these fluids and this prevents them from reaching and damaging the other non-resistant laminations. An appropriate adhesive such as cement is used to secure strip 26 to strip 25.

Upon the surface of strip 25 is applied the de# corating stamp strip 21 which is made preferably from rubber or syntheticv rubber and carries upon its outer facel theA embossed decorating indicia at 2t. The stamp strip 2'! is bonded to strip 26 by' Va suitable adhesive or cement in the same man' ner as the other laminations of the shoe. Printing strip 21 is thin and flexible so as to conform readily to the ware contour. It provides a relatively high coefiicient of friction with the ware surface so as to rotate the Ware without slippage or skidding, which would cause smudging of the decoration.

A side plate 30, secured to the base member 2li by screws 3| is located along one or both sides of the stamp unit, as illustrated in Figures 3 and 4. The side member aids in stabilizing thefoundation and maintains i-t in alignment longitudinally and increases the firmness of strip 2.3 by preventing lateral bulging of the strip under compression. An angular bracket 3 2 (Figures 1 and 2), is applied to the trailing end of the stamp foundation, being secured to base 28 by screws 33. This bracket ai-ds in locating and maintaining the stamp foundation upon the base member 29. lt is omitted from the leading end of the stamp member because it is desirabley to provide a resilient surface to avoidbreakage of the handle.

While illustrated and described with reference to a tea cup, the present structure may be utilized for many other ware shapes since the laminated foundation provides a wide latitudeA of yieldability. Ware varying from cylindrical to curved and angular profiles substantially different from the profile illustrated, may be decorated successfully. It will be. noted that theV foundation is wider at the bottom than at the stamping face. This permits very substantial distortion which is necessary to accommodate flared profiles of the type illustrated. It has been found that the resiliency of the stamp foundation. permits it to be applied also to Ware pieces having somewhat eccentric contours since the resiliency of the unit permits it to compensate for Variations in concentricity without blurring or smudging.

It will be apparent that the compressibility of the graduated layers may be. variedfto suit various other classes of Work by utilizing the proper materials and by properly combining them to out other classes of Work by utilizing theA proper produce the desired result. It has beenY discov ered however that remarkably clear and sharp designs, devoid of smudges or blurs, are obtained by using the arrangement disclosed.

In operation, as disclosed in the previously noted co-pending application, the drum I2 is pro-` vided with `two stamping units diametrically QP' posed `to each other. The apparatus includes inking mechanism which applies to the printingV face 2i', a nlm of ink which in the next half revolution of the drum is Vapplied to the ware. Thus, while one of the' stamps is performingfthe printing operation the other is beink inked. Aspreviously noted the ware is carried upon a rotatable chuck (not shown) which is urged under. predetermined spring pressure toward theA printing stamp so that the degree of pressure engagement of the stamp against the ware may be controlled. As utilized in conjunction withV this machine the operation is semi-automatic, the cups being placed upon thefchuck manually and removed manually after printing. It willbe apparent also that the improved structure may be applied to hand operated mechanisms as well as to other automatic power operated machines.

Having described my invention, I claim:

1. A compressible printing stamp adapted to be tracked in pressure engagement upon the outer surface of a rotatably mounted cylindrical ware piece having a flared profile to apply decorations thereon, said printing stamp comprising; -an elongated arcuate mounting member formed of rigid material, a pair of relatively thick elongated base strips secured together side by side and mounted upon the mounting member, said base strips being formed of resilient sponge material, each strip having a different degree of resiliency, the softer of said strips being adapted to be compressed to a greater extent than the rmer strip when the printing stamp is tracked in pressure engagement upon the ware piece whereby said strips provide substantially uniform pressure under non-uniform compression to compensate for the flared prole of the ware piece, a control strip coextensive with and secured upon the outer surface of the base strips, the control strip being formed of flexible material having resistance to stretching laterally, a cushion strip secured upon the outer surface of the control strip, the cushion strip being formed of resilient sponge material and having substantially the same thickness as said base strips, a decorating strip formed of relatively thin flexible material, and means for mounting said decorating strip upon said cushion strip, said control strip being adapted to control lateral bulging of said base and cushion strips when the decorating strip is tracked in pressure engagement upon the surface of the ware piece.

2. A compressible printing stamp adapted to be tracked in pressure engagement upon the outer surface of a rotatably mounted ware piece to apply decorations thereon, said printing stamp comprising: an elongated arcuate mounting member formed of rigid material, a pair of relatively thick elongated base strips secured together side by side and mounted upon the mounting member, said base strips being formed of resilient sponge rubber, each strip having a different degree of resiliency, the softer of said strips being adapted to be compressed to a greater extent than the firmer strip when the printing stamp is tracked in pressure engagement upon the ware piece whereby said strips provide substantially uniform pressure under non-uniform compression to compensate for the flared profile of the Ware piece, a control strip coextensive with and secured upon the outer surface of the base strips, the control strip being formed of exible rubber having resistance to stretching laterally, a cushion strip secured upon the outer surface of the control strip, the cushion strip being formed of sponge rubber having substantially the same degree of softness as the softery f said base strips and having substantially the me thickness as the base strips, said control fstiipbeing adapted to control lateral bulging ofsaid base and cushion strips under compressionan absorbent strip formed of resilient sponge material mounted upon the outer surface of said cushion' strip, and a decorating strip formed of flexible rubber mounted upon the outer surface of the absorbent strip, the decorating strip being narrower in Width than the combined base strips, the sides of the control, cushion, and absorbent strips being tapered inwardly toward the 4edges of the decorating strip to provide increased compressibility.

RAY J. RILEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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