US 3153804 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Oct. 27, 1964 D. .1. SILVER RESERVOIR MARKING INSTRUMENTS 2 Sheets-Sheet 1 Filed March 8. 1963 4 1V ilnnliutvulu llillla II M 4. r Ila/Ill!!! Oct. 27, 1964 D. J. SILVER RESERVOIR MARKING INSTRUMENTS 2 Sheets-Sheet 2 Filed March 8, 1963 mmi smm
United States Patent 3,153,304 RESERVOIR MARKING INSTRUMENTS Derrick John Silver, Letchworth, England, assignor to Mentmore Manufacturing Co. Limited, Stevenage, England, a company of Great Britain Filed Mar. 8, 1963, Ser. No. 263,992 Claims priority, application Great Britain, Mar. 1962, 9,216/ 62 14 Claims. (Cl. 15569) This invention relates to reservoir marking instruments of the type (hereinafter referred to as the type specified) comprising a barrel or reservoir adapted to contain a supply of a marking liquid, such as ink, a writing tip or marking element (which may be composed of felt or similar material) mounted slidably in one end of the barrel and a valve disposed within the barrel adjacent to the writing tip so that it normally shuts off the reservoir from the writing tip but can be actuated by applying pressure to this tip to permit marking liquid to flow to the tip from the reservoir.
Instruments of this type have generally had valves which are relatively complicated and expensive, both to manufacture and assemble, and require the provision of a barrel of somewhat larger external diameter than a standard size of fountain pen. The valve also has generally included a spring which is in contact with the marking liquid and when the latter, as is desirable in the case of marking instruments intended for use by children, comprises an aqueous vehicle and non-toxic colouring agents, the spring is liable to rapid deterioration with a consequent early failure of the instrument.
The present invention provides improved instruments of the type specified embodying valve arrangements of simple and cheap construction which enable the production of instruments with suitably small external diameters for convenient use by children.
Accordingly this invention consists in a reservoir writing instrument of the type specified in which the valve comprises a resilient and elastic non-metallic body having a part thereof held against displacement inwardly of the reservoir and another part thereof normally bearing against a valve seat but separable therefrom by a temporary deformation of the body produced by movement of the writing tip inwardly of the reservoir.
Some examples of marking instruments in accordance with the invention will now be described with reference to the accompanying drawings, wherein:
FIG. 1 is an elevational view of a pencil-like instrument with its point-protecting cap in place thereon;
FIG. 2 is a sectional elevation of the instrument with the cap removed and part of the barrel broken away, drawn to a larger scale;
FIG. 3 is a section taken on the line I[[Il1 of FIG. 2;
FIG. 4 is a section taken on the line IVIV of FIG. 2;
FIG. 5 is a section taken on the line VV of FIG. 2;
FIG. 6 is a fragmentary view corresponding to the lower end of FIG. 2 but showing the valve body deformed to the valve-open position;
FIG. 7 is a fragmentary sectional view similar to that of FIG. 2 but showing an alternative construction of writing tip;
FIG. 8 is a section taken on the line VIII-VIII of FIG. 7;
FIG. 9 is a section taken on the line D(]X of FIG. 7 of a detail of the writing tip;
FIG. 10 is an elevation of another detail of the writing tip shown in FIG. 7;
FIG. 11 is a longitudinal section of yet another form of writing tip;
FIG. 12 is a section taken on the line XIIXII of FIG. 11;
Patented Get. 27, 1954- FIG. 13 is a fragmentary sectional elevation showing an alternative construction of marking instrument, and
FIG. 14 is a section taken on the line XIVXIV of FIG. 13.
Referring first to FIGS. 1 to 6, it will be seen that the marking instrument comprises a tubular pencil-like holder portion or barrel 1 of substantially cylindrical shape having a detachable push-on cap 2 (FIG. 1) for protecting the marking tip.
The barrel (see FIG. 2) is adapted to be closed at one end by a plug 3, after it has been filled with a coloured marking liquid 4, and is formed internally with an annular shoulder 5 near the other end at the junction between the reservoir space and a cylindrical axially extending passage 6 of smaller diameter than this space.
This passage 6 serves to accommodate a length of felt rod 7, of square cross-section, which is a sliding fit at its edges in the passage and is longer than the latter. The upper end 7a of the rod is contained in a plane normal to the axis of the rod and the lower end 7b is contained in a plane inclined with respect to the first plane, for example, :to make a dihedral angle therewith of about 45.
At its upper end the rod 7 is fitted tightly into an appropriately shaped recess 8a formed in the lower end of a valve element 8 of resilient and elastic material, for example, rubber, which is received loosely within the lower part of the reservoir space of the barrel 1 (as viewed in FIG. 2). The valve element is of circular cross-section and is formed with an axially extending cavity 812 which opens into the central portion of the base of the recess 3a, the cavity preferably tapering somewhat (as shown) towards its closed upper end which is spaced a short distance from the upper end of the valve element. This upper end is of hemispherical shape and its central portion fits into a partspherical recess 9a formed centrally of the lower face of an abutment member 9 which extends diametrically across the reservoir space and is a tight fit therein, preferably being cemented in place. The abutment member 9 is relatively narrow (see FIG. 3) so that it leaves unobstructed passages 10 (FIG. 3) at each side thereof for the flow of marking liquid. It will be understood that the abutment member is secured in place after the valve element 8 has been introduced and before the reservoir space is filled with marking liquid.
The lower end of the valve element, externally of the recess 8a. therein, is a fiat annulus contained in a plane normal to the axis of the element and bears with some pressure upon the inner marginal area of the shoulder 5 within the barrel 1, the abutment member 9 being suitably disposed to ensure this.
It will be appreciated that, in the normal position of the parts (with the instrument held point downwards), the marking liquid 4 filled into the reservoir space will be unable to gain access to the felt rod 7 because the valve element 8 seals the lower end of the space by reason of its engagement with the shoulder 5 within the barrel.
When the marking instrument is to be used for the application of marle'ng liquid to a writing surface, such as that indicated at 11 in FIG. 6, by means of the inclined writing point constituted by the lower end 712 of the felt rod 7, the user presses this point on to the writing surface 11 in such a way as to urge the rod 7 axially upwards into the barrel 1 of the instrument, as shown in FIG. 6. The pressure thereby exerted upon the value element 8 causes the later to be pressed against the rigid abutment member 9 and therefore to be compressed axially with the lifting of its lower end face Sc clear of the shoulder 5 Within the barrel 1. Marking liquid then flows past this shoulder into the clearances between the fiat faces of the rod 7 and the surface of the passage 6 in which it is accomrnodated and contacts those faces of the rod. The liquid is absorbed by the felt of the rod and any excess '2 is tends to collect in the clearances. Upon release of the pressure exerted on the point of the rod, the valve element 8 resumes its normal shape and disposition so that its lower end face 80 again seals the reservoir space from the felt rod 7.
The user may then apply the liquid absorbed in the felt rod 7 to the writing surface (the barrel 1 being disposed in the normal writing position relative to the surface 11 during this operation) and may replenish the ink in the felt rod from time to time, by repeating the pressing action referred to above.
It should be noted that the axial compression of the valve element, with the consequent movement of part of the rod 7 into the reservoir space, causes some displacement of marking liquid from the reservoir space into the clearances about the rod 7 and that the return of the element 8 to its normal shape not only tends to cause any sur lus liquid in these clearances to be drawn back into the reservoir space but also causes the necessary liquidreplacing air to pass into the reservoir space.
An additional advantage is that the axial compression of the element 8 causes this to expand radially and thus restrict the flow of liquid to the portion of the reservoir space adjacent to the shoulder 5. Excessive pressure upon the point of the rod 7 may even cause sufficient radial expansion of the element 8 to shut off the further flow of liquid past the element. Hence, flooding of the passage 6 with marking liquid is largely prevented.
FIGS. 7 to 10 illustrate a different construction of marking tip, the other parts being the same as those already described in relation to FIGS. 1 to 6 and being indicated by the same reference numerals as before without further description here. 4
In this case, the writing tip comprises a cylindrical tube 12 somewhat longer than the passage 6, in which it is accommodated with some radial clearance, and containing, as a tight fit, a length of felt rod 13 (see also FIGS. 9 and 10). The tube 12 is formed from a relatively soft plastics composition. Near its inner end the tube is formed with opposed relatively large apertures 12a through which the felt rod bulges, at 13a into contact with the surface of the passage 6. As shown, the rod 13 is formed with a diametral slit 13b extending from its inner or upper end at least to the level of the lower edges of the apertures 12a before it is inserted in the tube so that axial compression of the rod will cause the latter to bulge outwards through the apertures, the rod 13 initially being somewhat longer than the tube 12. The ends of the rod are level with the respective ends of the tube, the upper end being contained in a plane normal to the axis of the tube and the lower end being contained in a plane making a dihedral angle of about 45 with the first plane. At its upper 'end the tube 12 is fitted tightly into the recess 8a in the lower end of the valve element 8.
The instrument shown in FIGS. 7 to 10 functions in the same manner as that described with reference to FIGS. 1 to 6, the marking liquid admitted to the annular clearance between the tube 12 and the wall of the passage 6 contacting those portions 13a of the felt rod 13 which bulge through the apertures 12a in the tube 12 and being absorbed by the felt.
FIGS. 11 and 12 illustrate another form of writing tip which may be used in place of the felt rod 7 of FIG. 2. Although it is possible to impart a sufiicient degree of stiffness to such a felt rod, without impairing its absorbency unduly, by suitably treating the felt, it is also possible to achieve the desired result by employing an untreated felt rod 14 (FIGS. 11 and 12) formed with an axial bore 14a in which is inserted, as a tight sliding fit, a length of wire =15. The wire, which may be of stainless steel or of some other rigid and non-corrodible material, is substantially shorter than the felt rod 14 and has rounded ends, the wire initially being fitted so that its one end is flush with the inclined writing face of the rod. As the latter wears away during use of the marking instrument the wire moves up the bore 14a so that the rod remains stiff to the required degree.
In FIGS. 13 and 14 there is illustrated another marking instrument embodying a somewhat different valve element and abutment member.
The barrel 1 has a reservoir space for the marking liquid 4 and a passage 6 of smaller diameter than this space, as in the construction of FIGS. 1 to 6, the junction between them affording the annular shoulder 5. The valve element 16 is a body of an elastic non-metallic material, such as rubber, formed of cylindrical shape with a square-section recess 16a in its one end and an axial cavity 16b of circular cross-section extending from its other end. In the recess 16a is tightly engaged the upper end of a belt writing tip. generally indicated by the numeral 17 and corresponding in every respect with the writing tip 7 shown in FIGS. 2 to 6.
The annular lower face 16c of the valve element 16 is pressed lightly against the shoulder 5 forming the valve seat by means of an abutment member 18 in the form of. an angularly bent strip of ispringyhon-corrodible metal which engages the internal wall of the barrel 1 by its transverse edges. The limbs of the member 18 are initially spread apart somewhat more than is indicated in FIG. 13 so that the member is placed under stress as it is forced down the space in the barrel to bear upon the valve member, the corners of the limbs biting into the material of the barrel so that the member 18 will be locked in its adjusted position and cannot be displaced upwardly by normal pressures exerted upon the valve member in the use of the instrument. As can be seen from FIG. 14 the member 13 has a maximum width less than the internal diameter of the barrel so that marking liquid can flow past the member quite freely.
As in the case of the instrument described with reference to FIGS. 1 to 6, the delivery of marking liquid 4 from the reservoir space in the barrel to the clearances around the writing tip 17 within the passage 6 is effected by pressing the tip inwardly of the barrel to cause axial compression of the valve member 16 with the consequent lifting of the lower face 16c of the latter clear of the valve seat 5. As before, the deformation of the valve member 16 produced by this axial compression causes some radial expansion of the member which tends to restrict the flow of the marking liquid past the valve member and thus prevents excessive delivery of liquid to the writing tip. 7
It will be appreciated that the member 16 need not be formed with the cavity 161) but may be solid at its upper end.
1. A reservoir marking instrument comprising a barrel having a reservoir space adapted to contain a marking liquid, a closure for said space at one end of said barrel, a passage formed at the other end of said barrel to open at one end into said space and at'the other end to the atmosphere, said passage being aligned with and of smaller cross-sectional area than said space, a valve seat formed within said barrel adjacent to the junction between said passage and said space to surround said one end of said passage, an abutment secured in said reservoir space, a rod-like marking tip slidably mounted in said passage with its one end projecting through said one end of said passage and its other and operative endnormally projecting through said other end of said passage, and an elastic non-metallic body disposed within said space in engagement with said one end of said tip and interposed be-" produced in marking operations, said body being compressible to a greater degree by the exertion upon said operative end of an inward pressure in excess of said normally produced pressures to cause temporary deformation of said body sufficient to separate said part thereof fiom said valve seat to allow flow of marking liquid into said passage.
2. A reservoir marking instrument as claimed in claim 1, in which said elastic body is of such a cross-sectional area relative to the cross-section of the portion of the reservoir space in which it is disposed that said body when temporarily deformed will restrict flow of marking liquid past said body.
3. An instrument as claimed in claim 1, in which said marking tip is of felt.
4. An instrument as claimed in claim 1, in which said passage is of circular cross-section and said marking tip is of rectangular cross-section.
5. An instrument as claimed in claim 1, in which said marking tip is formed with an axial bore and a rigid element is engaged as a tight sliding fit in said bore.
6. An instrument as claimed in claim 1, in which said marking tip comprises a tube formed with apertures near the end thereof adjacent to said body and a felt rod fitted within said tube with parts thereof bulging through said apertures into the space between said tube and the wall of said passage.
7. In a reservoir marking instrument comprising a tubular pencil-shaped barrel closed at one end which provides a reservoir space for marking liquid and which is formed at the other end with a passage aic'ally aligned with and opening into said space but of smaller crosssectional area than the latter, the junction between said space and said passage defining an annular valve seat and a marking tip being inwardly slidable in said passage by pressure exerted upon its operative end, an elastic nonmetallic valve body fitted Within the reservoir space in engagement with said marking tip between the latter and a fixed abutment normally to bear upon said valve seat, thereby preventing flow of marking liquid to said tip, and to hold said tip against inward movement under the action of pressures normally employed in marking operations but to be deformable away from said seat by inward movement of said tip produced by a pressure in excess of said normally employed marking pressures so as to allow flow of marking liquid to said tip.
8. A reservoir marking instrument comprising a felt marking tip, a reservoir for marking liquid and a valve for permitting said liquid to flow to said tip whenever said valve is opened by inward movement of said tip, said valve comprising a valve seat and a co-operating body of elastic non-metallic material engaged with said tip and interposed between an abutment within said reservoir and said tip in a compressed condition such that inward movements of said tip for opening the valve will alone be produced by pressures in excess of those normally employed in marking operations.
9. A reservoir marking instrument comprising a barrel having a reservoir space adapted to contain a marking liquid, a closure for said space at one end of said barrel, a passage formed at the other end of said barrel in axial alignment with but of smaller cross-sectional area than said space, one end of said passage being open to the atmosphere and the other end being open to said space, an annular valve seat formed at the junction of said passage and said space, a fixed abutment extending across but not filling the cross-section of said reservoir space at a distance from said valve seat, a body of elastic nonmetallic material engaged under light compression between said abutment and said valve seat normally to bear upon the latter under the action of its own elasticity, and a felt marking tip slidably mounted in said passage with its one end attached to said elastic body and its other end normally projecting out of said passage, movement of said tip inwardly of said passage under the action of pressures normally employed in marking operations being resisted by said elastic body so that only the exertion upon said tip of a pressure exceeding said normally employed pressures can urge said tip inwardly of said passage to compress said body axially against said abutment and deform it away from said valve seat to allow flow of marking liquid to said tip.
10. An instrument as claimed in claim 9, in which said v elastic body is of such a cross-sectional area that the radial expansion thereof consequent upon its axial compression will bring its outer surface over at least part of its length into liquid flow-restricting relationship with the wall of said reservoir space.
11. An instrument as claimed in claim 9, in which said marking tip is tightly engaged in a recess formed in said elastic body.
12. An instrument as claimed in claim 9, in which said abutment is a rigid element firmly engaged at its ends with the wall of said reservoir space.
13. An instrument as claimed in claim 9, in which said abutment is a resilient element firmly engaged at its ends with the Wall of said reservoir space under the action of its own resilience.
14. An instrument of the character described comprising a tubular barrel closed at one end and fitted at the other end with an axially slidable felt marking tip, an abutment secured in said barrel but not obstructing the passage therethrough, a valve seat within the barrel adja cent to said tip and a co-operating elastic non-metallic valve body engaged between said seat and said abutment under a degree of precompression ensuring that inward axial movement of said tip capable of deforming said body elastically away from said seat will be produced only when a pressure is exerted on said tip in excess of the pressures normally employed in effecting marking operations with said tip.
References Cited in the file of this patent UNITED STATES PATENTS 2,762,337 Beckwith Sept. 11, 1963