US2847976A - Spacer pattern for capillary reservoir elements - Google Patents

Description

Aug. `19, 1958 R. L sPAuLDlNG 2,847,976

' sPAcER PATTERN RoR CAPILLARY RESERVOIR ELEMENTS Filed Oct. 28, 1955 2 Sheets-Sheet 1 FG. l'.

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l Ill l ll Ill A wup/v By All@ 1.9, 1958 R. l. sPAuLDlNG 2,847,976

l sPAcER PATTERN FoR CAPILLARY RESERVOIR ELEMENTS Filed oct, 28, 1955 2 Sheets-Sheet 2 RA wvo/v0 .SPA ULD/Nei f/VVE/VTOR SPACER PA'ITERN FOR CAPILLARY RESERVOIR ELEMENTS Raymond L. Spaulding, Janesville, Wis., assigner to The Parker Pen Company, Janesville, Wis., a corporation of Wisconsin Application October 2 8, 1955, Serial No. 543,355

2 Claims. (Cl. 1Z0- 50) This invention relates in general to capillary reservoir or ller-and-reservoir elements for writing instruments and in particular to such elements having thin walls spaced apart by spacers projecting from said Walls.

Cylindrical capillary iiller-and-reservoir elements of this type are known wherein perforated thin Walls are spaced apart radially by spacers of either generally cylindrical or dome-like shapes.

These prior art elements have the disadvantage that, if the spacers are'relatively small and spaced relatively far apart, the thin walls bend or sag at various places thereby preventing the walls from being uniformly spaced apart a distance equal to the height of the spacers. The bent portions of the wall may partially or totally block or cover the perforations in an adjoining wall and may also block a portion of the space between a pair of adjoining walls. The sagging or bending of the Walls thus impedes the flow of ink through the spaces, both axially (longitudinally) andradially (laterally) of the reservoir element.

These prior art elements also have the disadvantage that, if the circular or dome-like spacers lare either increased in size or placed close together, to provide sul`n`cient radial support throughout the element for uniformly spacing the Walls by preventing sagging or bending, the ink storage capacity of the reservoir element is prohibitively decreased and the flow of ink axially (longitudinally) and radially (laterally) is prohibitively impeded.

It has been discovered in connection with this invention that the provision of generally rectangular elongated spacers patterned properly on the Walls overcomes the above disadvantages. If the spacers are disposed with their elongate dimension parallel to the axis of the cylindrical element they present the least impedance to axial (longitudinal) ink ow but they then have the disadvantage of being extremely diicult to radially (laterally) align to provide proper radial support for obtaining nonsagging walls and uniform wall spacing. If the spacers are disposed with their long dimension perpendicular to the longitudinal axis of the element they can be conveniently radially aligned to provide proper support for obtaining non-sagging Walls and uniform wall spacing but they then have the disadvantage of presenting the maximum possible impedance to the axial flow of ink.

All of the above disadvantages are overcome by this invention by providing a plurality of generally rectangular elongated spacers with their elongated dimension lying on the walls acutely angularly of the longitudinal direction of the element in a pattern which provides lateral support for obtaining non-sagging walls and uniform wall spacingand provides ink paths for the effective llow of ink longitudinally and laterally through the element.

lt is therefore an object of this invention to provide a capillary reservoir element having perforated thin walls spaced apart laterally by spacers arranged on the Walls in a pattern which provides, Without substantially decreasing the ink storage capacity of the element, sufficient nited States Patent 2,847,976 Patented Aug. 19, 1958 and proper support for uniformly spacing the walls apart laterally through the spaces between walls.

Another object of this invention is to provide a capillary reservoir element having thin walls spaced apart laterally by spacers arranged on the Walls in a pattern such that the spacers may easily be aligned laterally for uniformly spacing the walls and such that effective ink paths are provided for the unimpeded flow of ink through the spaces between walls.

It is a further object of this invention to provide a cylindrical capillary reservoir element having thin walls radially spaced apart by spacers arranged on the walls in a pattern which provides, Without substantially decreasing the ink storage capacity of the element, both proper radial support for obtaining non-sagging walls uniformly spaced and for obtaining effective ink paths for f unimpeded ow of the ink through said spaces axially and radially of the element.

Objects and advantages other than those mentioned hereinbefore will be apparent from the following description when read in conjunction with the accompanying drawings, in which:

Fig. l is a plan view of a sheet having spacers arranged thereon in accordance with one embodiment of the inventlon;

Fig. 2 is an enlarged view of a portion of the sheet shown in Fig. 1;

Fig. 3 is a sectional view taken along line 3-3 of Fig. 2;

Fig. 4 is an isometric view illustrating how a capillary reservoir element may be formed from a sheet such as is shown in Fig. l;

Fig. 5 is an isometric view of a capillary reservoir element embodying the invention;

Fig. 6 is a sectional view taken along line 6-6 of Fig. 5

Fig. 7 is a sectional view taken along line 7-7 of Fig. 5; and

Fig. 8 is a view, partly in section, embodying the invention.

Referring to the drawings, there is shown in Figs. l-4 inclusive, a sheet 20 of perforated thin walledmaterial such as plastic or metal foil having secured thereto a plurality of generally rectangular elongated relatively rigid spacers 21 all projecting an equal distance (height) from the sheet, the sheet being capable of being spirally rolled upon itself to form a generally lcylindrical reservoir element 22, as shown by Figs. 5-7 inclusive, having uniformly radially (laterally) spaced convolutions or walls 23 defning capillary ink storage spaces 24 therebetween which extend axially (longitudinally) of the element. The sheet has perforations 25 therethrough.

The axial or longitudinal direction of the reservoir element is shown horizontally in Figs. 5 and 8, vertically in Figs. l and 2, and angularly in Fig. 4. The radial or lateral direction is shown vertically in Fig. 8 and radially in Figs. 5, 6 and 7. The terms axially and longitudinally are used herein interchangeably and are synonymous. The same is true with reference to the terms radially and laterally.

The spacers 21 may be of any suitable material such as plastic or metal and are preferably imperforate, the perforations preferably being through the sheet proper, thereby eliminating the possibility of forming burrs thereof a fountain pen on thus 'better insuring that all the spacers will be of their intended height to thereby space the Walls 23 the intended distance. The elimination of burrs on the spacers also eliminates ink and air traps being formed where the rough burred endsk thereof would engage an adjacent wall.

To the end that the reservoir element 22 has laterally uniformly spaced non-sagging walls and has effective ink paths both laterally and longitudinally'I ofthe element, the spacers 21 are rigid relative to the thin walls 23 and are arranged on the walls in a pattern particularly advantageous to these ends. The spacersare disposed in spaced apart relationl leaving gaps therebetween so that the ink may'flow in the interwa'll spaces in all directions. The spacers are spaced axially and'convolutely, and the inter-wall spaces are connected radially'by perforations 25 in the walls.V The'ink' can thus Yeffectively flow axially (longitudinally),l convolutely (circumferentially) and radially (laterally).

The spacers 21 lie on the walls acutelyjangularly of the longitudinal direction ofthe reservoir element 22 formed by the walls 23. Acutely angularly'as used herein means at a finite acute angle less thanninety degrees. The spacers are arranged to align intersectingly, as best can be seen in Figs; 5 and 7. Intersect, intersecting and intersectingly` as used herein do not mean'actually tech- `nicallyinter'secting as twolines meeting at a common point but mean intersecting inthe'broader'sense as more commonly understood, as an underground cable intersects a highway and as a Vbridge intersectsa river, where two lines intersect although they may be in different and parallel planes.

The spacers preferably lie at the acute angle of-fortytive degrees to the'longitudinal axis of the velement and the spacers preferably intersect perpendicularly, although satisfactory results can be achieved Awith acute angles other than forty-live degrees and with intersections other than perpendicular.

Fig. 6 electively'illustr'ates the radial (lateral) alignment of the spacers and further illustrates how the lengths of the spacers on adjacent walls progressively increasefrom the innermost'wall to 'the outermost wall.

Fig. 7 clearly illustrates the intersecting alignment radially (laterally) and' shows the spaces intersecting perpendicularly.

Fig. l shows one manner of disposingthe spacers on a sheet to be spirally rolled upon itself to form a generally cylindrical capillary ller-and-reservoir element having radially spaced walls. The spacers 21 are attached or secured to the sheet `in lany suitable manner and may be formed integrally therewith. The spacers are preferably all disposed on one side of the sheetthe inside of the sheet when spirally rolled as Vshown in Fig. 4, to form the convolute, generally cylindrical reservoir element shown in Fig. 5. The horizontal direction in Fig. l is referred to herein as the convolute or circumferential direction and the vertical direction as the axial or longitudinal direction.

The spacers 21 are arranged 'in a plurality of parallel convolute rows. Each spacer in each convolute row is disposed one complete convolution from a transversely disposed spacer so that when spirally rolled up, the spacers radially align intersecting'ly.r Each of the convolute rows contains groups of spacers. Each of these groups extends convolutely one complete convolution and contains therein an equal number of spacers Yspaced apart evenly convolutely. Thus when the sheet is spirally rolled into the cylindrical form of reservoir element each spacer in each group is in radial alignment with a corresponding spacer `in each adjacent group.

The spacers within each group are parallel to each other but perpendicular to the spacers within each adjacent group and thus, when the `sheet is rolled up, each spacer 21 on any one convolution or wall 23 is not only in radial alignment with but also intersects perpendicularly a corresponding spacer on each adjacent convolution or wall 23.

The convolute rows of spacers are spaced apart evenly axiallyand the perforations 25 are conveniently arranged in parallel convolute rows intermediate the convolute rows of spacers.

The spacers in adjacent convolute rows are` staggered or unaligned so as not to impede ow of ink axially (longitudinally) of the reservoir element. This is accomplished by arranging the spacers so that the spacers in alternate convolute rows form parallel rows axially of the element. This staggered or scattered pattern of the spacers allows the ink to flow eiectively axially of the reservoir element through the ink -storage spaces.

Within each group in every row, the spacers are paralleland evenly spaced convolutely a sufficient distance to prevent ink from forming a meniscus bridging two convolutely spaced spacers to thus impede or block ink ilow axially of the element. The convolute distance between groups, i. e. from the last spacer in each group to the first spacer in the next group isalso of a sufficient distance to prevent such menisci and the attendant blocking of or impedance to axial ink flow.

The spacers in each convolute row increase in length from the innermost convolution or wall 23 to the outermost convolution or wall 23, as the convolutions themselves increase in convolute or circumferential length. The spacers on the inner convolutions need not be'as long as they must be on the outer convolutions to give the walls the rigidity and support necessary for uniform or even wall spacing. This'arrangement results in a reservoir element of more storage'capacity than would be the case if the same sized spacers were used throughout the element as were used on the outermost wall, and also results in a saving of the material from which the sapcers are made. As shown in Fig. l, the spacer lengths increase, group by group, i. e. the spacers within each group are all of the same length but of a different length than' the spacers within any other group. The spacers, however, can be arranged to continuously increase in length throughout each convolute row and need not increase group by group, or they can be arranged so that two or more adjacent groups contained spacers of equal lengths but of different lengths than the spacers in groups convolutely disposed from said two or more groups.

One of the important advantages of having the spacers increase in length from the innermost convolution to the outermost convolution is that this facilitates the substantial radial alignment of the spacers during the winding operation. Winding tolerances can thus be less strict than would be the case if the spacers were all of the same length. Thus, even though the center points of the spacers are not perfectly aligned radially because of lack of perfection inthe practical manufacturing winding techniques, the spacers will intersect at points other than their centers and still provide the necessary radial support for giving the desired rigidity and wall to wall spacing. The deviations from perfection in the winding technique are thus compensated for by providing spacers of varying lengths, increasing in length from the inner convolution to the outer convolution.

The spacers may all be of the same height to thereby space all of the walls the same distance apart, or the height of the spacers may be varied group by group or continuously, in a manner similar to that described above for the length of the spacers, to accomplish a progressively varying wall spacing throughout the reservoir element. It may, for example, be desirable to space the inner walls more closely than the outer walls. The spacers are shown in Figs. 3, 6 and 7 as all being of equal height, but spacers of varying height are within the scope of this invention.

The height of the spacers of course must be such to provide the reservoir element with the wall spacing which obtains the necessary and desired capillarity. The fillerand-reservoir element is designed so that when used in a writing instrument it will have sufficient capillarity to fill itself by capillary action and to maintainink therein under all normal circumstances but insuflicient to prevent withdrawal of ink during writing. The width of the spacers should be as small as possible so that the spacers do not unnecessarily decrease the ink storage capacity of the reservoir element. The length of the spacers is selected to give the necessary rigidity to the walls to aid in maintaining uniform wall spacing but not to interfere with the rolling operation in forming the reservoir. Dimensions will depend to some extent upon the thickness of the walls and upon the materials used for walls and spacers. Dimensions which have proved satisfactory but are not to be construed as limiting the invention are as follows:

For a sheet of plastic material about .001 thick, spacers of plastic may be about .017 wide, in the range of about .008l high, and may have lengths of about .050" for the spacers in the group on the innermost wall, the lengths increasing as above explained to about .125 for the spacers in the group on the outermost wall.

Fig. 8 illustrates a writing instrument such as a fountain pen embodying a reservoir element constructed in accordance with the invention. A barrel 26 and a shell 27 house the internal elements of the pen. The reservoir element 32 is disposed within a casing 28 open at both ends. All the elements of the pen except the barrel are firmly secured to the shell. The barrel is removable from the casing and shell structure and when removed exposes the rear end of the reservoir element so that the reservoir element may be lled by capillary action by dipping the exposed rear end of the pen in ink. A writing element 29 communicates with the reservoir through a collector member 31 and a feed element 30. The reservoir element 32 is of the type described herein above having laterally spaced walls forming longitudinally extending ink storage and transfer spaces between the walls. The spaces provide for ow of ink longitudinally therethrough from the rear of the reservoir element up to the collector member 31 at the front of the reservoir element. Perforations through the walls provide for the ow of ink laterally through the reservoir element from the outside wall thereof adjacent the inside of casing 2S to the feed element 30 disposed inside the innermost wall of the reservoir element. The spacers (not shown) are arranged on the walls acutely angularly of the longitudinal axis of the element and the spacers are in lateral alignment intersectingly. The walls thus are properly supported laterally to uniformly space the walls and to prevent sagging or bending. The spacers therefor function to provide elfective unimpeded paths for the flow of ink both longitudinally and laterally through the reservoir element to the collector member and to the feed element. The ink finds its way from the feed element and collector member to the writing element in a manner Well known in the art.

The invention is applicable to a cylindrical reservoir element comprising a plurality of radially spaced concentric tubes and is also applicable to a reservoir element coniprising a plurality of flat walls spaced laterally apart although such embodiments of the invention have not been shown. ln the case of the laterally spaced flat walls, there is no need for spacers of varying length, but the other features of the invention apply.

Features disclosed but not claimed herein are disclosed and claimed in copending application Serial No. 542,844, tiled October 26, 1955, of John Dyson, assigned to the same assignee as is this application.

Although only one embodiment of the invention has been shown and described, it will be apparent to those skilled in the art that other modifications and variations may be made therein without departing from the spirit of the invention and the scope of the appended claims.

I claim:

l. A capillary iller-and-reservoir element for a writing instrument comprising a perforated sheet of thin walled material spirally rolled upon itself, a plurality of elongated spacers lying on Ione side of said sheet spacing the convolutions thereof to dene between said convolutions a spiral ink storage space extending axially of said element, said spacers lying on said sheet at forty-tive degrees of the axial direction of said element, said spacers being arranged in parallel rows convolutely of said element, said convolute rows being spaced apart evenly axially of said element, said convolute rows having therein groups of spacers, each group extending convolutely one complete convolution of the sheet, each group having an equal number of spacers therein spaced apart evenly convolutely, the spacers within each group being parallel, the spacers in adjacent groups being perpendicular, in every convolute row each spacer in each group being disposed one complete convolution from a corresponding spacer in each adjacent group whereby each spacer in each group is in intersecting radial alignment with corresponding spacers in every other group, the spacers within each group being of equal lengths but being of different length than the spacers within any other group, the length of the spacers increasing group by group from the group on the innermost convolution to the group on the outermost convolution, said element having sufficient capillarity to ll itself by capillary action and to retain the ink therein but insuiicient to prevent withdrawal of ink in writing.

2, A capillary tiller-and-reservoir element for a Writing instrument comprising a perforated sheet of thin walled material spirally rolled upon itself, a plurality of elongated spacers lying on one side of said sheet disposed thereon throughout its length and breadth spacing the convolutions thereof throughout their length and breadth to define between said convolutions a spiral ink storage space extending axially of said element, said spacers lying on said sheet acutely angularly o'f the axial direction of said element and being arranged in intersecting radial alignment so that the spacers on adjacent convolutions intersect thereby providing radial lines of support from the innermost convolution to the outermost convolution and there by providing ink paths for the effective flow of ink axially and radially of said element, said element having sufficient capillarity to fill itself by capillary action and to retain the ink therein but insuiiicient to prevent withdrawal of the ink in writing.

References Cited in the tile of this patent UNITED STATES PATENTS

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