US2847972A - Stamp pads - Google Patents

Description

I 1953 s. N. RosEnLTHAL 2,847,972

STAMP PADS Filed March 19, 1956 |8 I? MUSLIN SHEE T I f" I6 FELT 4 INK LEvEL l5 GLASS wooL .1 l

FELT

l2 A 4 I25 \IS (IZALFELT INVENTOR. SIDNEY N. ROSENTHAL BY Q fiat ATTQRNEYS United tates Patent STAMP PADS Sidney N, Rosenthal, Richmond Hill, N. Y. Application March 19, 1956, Serial No. 572,518 1 Qlaim. (Cl. 113-265) This application relates to stamping pads and particu' larly to a stamping pad especially designed for highly volatile opaque ink of the clogging type, characterized by rapidity of evaporation of the carrier fluid of the ink with a consequent residue of ink particles which would normally tend to clog the stamping pad.

A stamp pad normally is a somewhat resilient pad saturated with ink and adapted to moisten by contact a rubber stamp or felt nib of a marking pen for inking the stamp or the nib.

A specific object of the present invention is to provide a stamping pad especially designed for ink of the character above described which is designed to reduce ink losses as well as hardening of the pad surface.

Further objects of the present invention will best be understood on reference to the appended drawing and the related specification.

In this drawing:

Fig. 1 is an elevation section view of one embodiment of the invention.

Fig. 2 is a top view of the pad with the cover removed.

Fig. 3 illustrates a front view of the closed container.

Referring to the drawings, it will be observed that Fig. 1 shows a stamp pad comprising a container having an open top normally closed by a friction fit cover 11 and containing a filler. The filler comprises two ink saturating felt pads 12 and 14. Placed between these pads is a layer of non-absorbent, non-saturating, resilient fibrous material 15, such as glass wool, of which one commercial form known by the trademark Dynel has been found especially suitable. The ink in the pad fills the container to a level somewhere between the upper and lower surfaces of the glass wool layer as indicated by the dotted line 16. The glass wool holds the ink upon its surfaces, but does not provide for capillary action.

The lower felt pad 12 is preferably made of doubly ply construction to contain plies 12A and 12B and each felt layer is formed with an air hole 17 normally closed by a felt plug 13 to enhance ink and air circulation through the felt pad. The double ply construction provides a space within the lower felt pad for a puddle of ink to gather.

The upper felt pad 14 is considerably harder and is thus of lower absorbent nature than the lower felt pad 12.

Covering the upper felt pad 14 is a muslin sheet or layer 22 conventional in stamp pad construction.

When a stamp is pressed down on the muslin sheet 22, and thus on the upper pad 14, such pad is moved down into the ink which is at the level 16 which is below the normal position of the upper felt pad 14. The glass wool .16 serves as a spring support for the upper pad 14, rather than as a sponge, and normally maintains the upper pad 14 out of contact with the ink at level 16, and thus minimizes the saturation of the pad 14 and the consequent loss by evaporation of the fluid of such ink.

In other words, the glass wool 16 functions as if it were a coil spring to maintain pad 14 out of contact with the ink, but to permit pad 14 to be moved down by stamping pressure to become saturated with the ink for wetting the pen nib or the stamp applied to the muslin 22 The glass wool layer 16 also functions to prevent splashing of the ink between the pads and to break up the flow of ink in the up and down movement of the pad 14 and thus to prevent splashing.

Because the lower felt pad 12 is more absorbent than the upper felt pad 14, ink tends to flow down from the space filled by the glass wool, rather than up. Thus, when pressure is applied to the upper pad 14, the ink adhering to the surfaces of the glass fibers is squeezed upward into the upper pad 14 and downwardly into the lower pad 12. Therefore, the upper pad does not become over-saturated and consequently, does not evaporate what would otherwise be excess ink in the upper pad.

This invention may be further developed within the scope of the following claim. Accordingly, it is desired that the foregoing description be read as illustrating one operative embodiment of my invention, rather than in a strictly limiting sense.

Now having described the stamp pad hereof, reference should be had to the following claim.

I claim:

A stamp pad for use with highly volatile inks comprising a container having an open top and two ink saturant felt pads at the bottom and top thereof; and a pad of glass wool between said felt pads; said glass wool pad being in contact with the felt pads and filling the space between them and supporting the upper felt pad; said container being adapted to contain ink at a level beneath the normal position of the top felt pad; the top felt pad being compressible into the container against the glass wool pad to reach the ink level and being maintained in its normal position above the ink level by the glass wool pad.

References Cited in the file of this patent UNITED STATES PATENTS 204,726 Hammond June 11, 1878 340,761 Chamberlain Apr. 27, 1886 1,538,241 Colville May 19, 1925 2,152,682 Dwofsky Apr. 4, 1939 2,375,178 Ruben May 1, 1945

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