US3819284A

US3819284A - Writing instrument

Info

Publication number: US3819284A
Application number: US00331043A
Authority: US
Inventors: E Kreuzer
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-02-21
Filing date: 1973-02-09
Publication date: 1974-06-25
Anticipated expiration: 1991-06-25
Also published as: ZA73900B; DE2208111C3; FR2173016A1; ES188895U; FR2173016B1; NL7300450A; IT978294B; DE2208111A1; NL156349B; GB1401123A; AU446608B2; ATA17773A; AU5228673A; DE2208111B2; JPS4926A; CH547179A; BR7301151D0; AT344042B; CA965915A; ES188895Y

Abstract

An ink writing instrument has a fibre-tipped writing point in communication with a wick-like ink reservoir housed in the instrument body, which also encloses another ink reservoir holding a reserve supply of ink, for emptying into the first ink reservoir when the latter is exhausted, emptying of the reserve ink reservoir being achieved by pushing inwardly a slidably mounted plunger which protrudes from the body, the position of the plunger outside the body indicating whether or not the reserve ink reservoir has been emptied.

Description

"United States Patent [191' Kreuzer 1 June 25, 1974 1 1 WRITING INSTRUMENT [76] Inventor: Erwin Kreuzer, Am Schlossbach 40,

5300 Bonn-Rottgen, Germany [22] Filed: Feb. 9, 1973 [21] Appl. No.: 331,043

[30] Foreign Application Priority Data Feb. 21, 1972 Germany 2208111 [52] US. Cl 401/151, 401/198, 401/199 [51] Int. CL; B43k 5/10, B43k 8/00 [58] Field of Search 401/151, 198, 199, 223,

[56] References Cited UNITED STATES PATENTS Silver Bross Bross Wiener 401/133 X 3,399,020 8/1968 Margolis et a1. 401/198 X FOREIGN PATENTS OR APPLICATIONS 1,231,132 12/1966 Germany 401/135 Primary Examiner-Charles Lawrence Attorney, Agent, or Firm-Lilling & Siege] [5 7] ABSTRACT 9 Claims, 3 Drawing Figures WRITING INSTRUMENT This invention relates to ink writing instruments, particularly, but not exclusively, those having writing tips enclosing capillary cavities or channels communicating with an ink reservoir such as wick housed in the body of the instrument. I

The writing tip of a writing instrument, frequently referred to briefly as a fibre-tipped pen, may consist of a porous nylon body. The wick-like ink reservoir tov which the writing tip is connected may consist of felt or the like. I

Fibre-tipped pens are frequently throw-away instruments which are discarded when the ink reservoir has been exhausted. A substantial disadvantage of all throw-away writing instruments, be they fibre-tipped or ballpoint pens is that one cannot easily perceive when they have already or are about to run out of writing fluid. Very frequently, such emptying occurs just when the writing instrument is needed and no replacement is available. I

A number of proposals are already known for provid-' ing ink writing instruments with a separate ink reservoir or container holding a reserve of ink in readiness to allow continued use of the instrument for some time after the ink contained in the main reservoir has been consumed. Emptying the reserve container for continued writing has necessitated an initial step of opening the body of the writing instrument before the user can gain access to the reserve container and bring its con-- tents into use. This is not only troublesome, but the cost of manufacturing the body of the writing instrument is substantially increased. This is because the body must be composed of two precisely worked parts matched exactly to one another dimensionally so as to be releasably engageable, the two parts may be interconnected for example by screwing them together. Such costly measures are therefore not very suitable for application in throw-away writing instruments, which should be particularly cheap. Known writing instruments with a reserve ink container also have the inherent disadvantage that one can only establish whether the supply of ink in the reserve container has already been taken into use by opening the body.

According to the present invention, there is provided a writing instrument comprising a body having a writing tip at one end and containing an ink reservoir communicating with the writing tip for supplying ink thereto, a second reservoir inside the body containing a reserve supply of ink for use when the first reservoir is exhausted, and an operating plunger element which is movably mounted in the body and is operable from the exterior thereof to cause the second reservoir to discharge its contents into the first reservoir. Further according to the present invention, there is provided a writing instrument having a body containing an ink reservoir wick communicating with capilliary passages of element, whether or not the second reservoir has been V 2 discharged, and therefore whether the instrument is almost spent.

The externally operable plunger of a fibre-tipped pen embodying the invention is preferably operated simply by pushing but could, instead, be advanced inwardly by a rotary action. The element can additionally be provided with an visible indication, for example a mark, which shows the initial position of the operating element and thereby makes it readily discernible to the user whether or not the reserve of ink has been taken into use.

In a preferred constructional form of the invention, the second reservoir is a wick or felt or the like which is arranged to be longitudinally slidable in response to operating the plunger into contact with element at a distance behind the first reservoir. If, after the first reservoir connected to the writing tip has been exhausted through writing, the operating element is pushed forward, that is towards the writing tip, then the second or spare reservoir is brought into contact with the first or main reservoir, so that the latter can absorb the ink from the spare reservoir and can continue supplying ink to the writing tip. In order to accelerate the transfer of the ink from the spare reservoir to the main reservoir, the main reservoir advantageously has a greater capillarity than the spare reservoir, which can be achieved, for example, by the fibre density being lower in the spare reservoir than in the main reservoir.

In order to prevent unintentional, premature emptying of the spare reservoir, the operating plunger element, may be locked in its initial, ready position such that it can be actuated only when a predetermined force is exerted thereon. For example, the plunger element may be prevented from moving inadvertently by a part of the body of the writing instrument conforming closely to, or mating with, the said element, there being provided in this part of the body a predetermined breaking point at which the part breaks away on forcing the operating element inwardly.

The invention will now be described by way of example with reference to the embodiments illustrated in the drawing, in which:

FIG. 1 shows a fibre-tipped pen according to the in vention'in which the ink reservoir designed to hold the reserve of ink is in the form of a wick slidable or displaceable by means of the operating element;

FIG. 2 shows a constructional form with a reservoir wick for the reserve of ink which is fixed immovably in the body of the pen;

FIG. 3 shows a constructional form in which the reserve of ink is in a liquid-charged pad.

Each pen illustrated in the drawings is fibre-tipped pen having a conical or tapered end containing a bore in which is fixed, in a manner known per se, a capillary writing tip 2. The inner or rear end of the tip 2 is embedded in a reservoir wick 3 composed of felt or some other fibrous material with a capacity for ink storage. The reservoir wick 3 is' supported at its front end nearest the tip 2 against a shoulder 1' of the body. In the embodiment shown in FIG. 1, the opposite, rear end of the reservoir wick 3 bears against an annular shoulder 4' on the inside of a plastics ring 4 forced into the body l. The internal bore of the ring 4 is stepped to form the annular shoulder 4' and its end remote from the reservoir wick 3 encloses the front end of a reservoir wick 5 designed to hold a reserve of ink. The rear part of the wick 5 is guided for sliding movement in an internal bore of an insert element 6 which is forced into the open rear end of the body 1. Moreover, in the insert element 6 there is a push pin 7, the rear end of which projects from the insert element 6 by an amount corresponding at least to the distance between the rear end of the reservoir wick 3 and the front end of the reservoir wick 5. The push pin 7 has a collar 8 extending into a groove 9 in the insert element 6. The push pin 7 consists of a comparatively easily deformable and preferably springy material which makes it possible to push it with accompanying deformation of the collar 8 into the internal bore of the insert element 6 until the collar 8 catches in the groove 9. Owing to the mating engagement of the collar 8 in the groove 9, the push pin 7 is secured against any unintentional, premature inward movement. However, the deformable nature of the pin 7 makes it possible for a sufficiently large force applied to the end of the pin 7 to overcome the resistance to inward movement thereof created by the collar 8 and groove 9. Instead of the mating locking of the push pin 7 which is shown here, its peripheral surface may be ccmented to the internal bore of the insert element 6, provided it is possible for the bond to be ruptured.

If the reservoir wick 3 has been exhausted through writing, the reservoir wick containing the reserve ink can be pushed forward by forcing the push pin 7 inwardly until the front end of the wick 5 comes into contact with the rear end of the reservoir wick 3, which thereafter absorbs the reserve ink from the reservoir wick 5 in consequence of capillary action and passes it on to the writing tip 2. The forced-in pushed pin 7 indicates that the supply of ink is now running out and complete exhaustion of the writing instrument must soon be expected.

The different shading of the two reservoir wicks is in tended to indicate that the fibre density of the reservoir wick 3, the size of the capillary passages between the fibres and, consequently, its capillary action are greater than the fibre density of the reservoir wick 5 and its capillary action.

In the embodiment shown in FIG. 2, the rear end of the reservoir wick 3 is supported against an inwardlytumed rim 6 at the front or innermost end'of the insert element 6, in which the reservoir wick 5 for the reserve of ink is so arranged that it is fixed immovably by the rim 6' and is held thereby at a certain distance from the rear end of the reservoir wick 3. The push pin 7 is so held in the insert element 6 by cementing that it can be pushed inwardly from its position shown in the drawing into the interior of the body only by the application of a predetermined force. In this case, the reservoir wick 5 is compressed, so that it releases the supply of ink contained in it and this is absorbed by the exhausted reservoir wick 3 and passed on to the writing tip 2.

In the embodiment in FIG. 3, the rear end of the reservoir wick 3 is held in a plastic ring 4 forced into the body 1. The ring 4 has an end face remote from the reservoir wick 3 which is in the form of a conical depression which opens into a throughflow orifice 4". In the chamber formed between the ring 4 and the insert element 6 there is a pressurized liquid pad 10 containing a reserve supply ofink. A push pin 7 is held in the insert element 6, the pin 7 being displaceable longitudinally pushed sufficiently hard to overcome a predetermined retaining force. The lower or inner end of the push pin 7 has a sharp point 11. If, after the ink reservoir 3 has been exhausted, the push pin 7 is forced inwardly into the body of the pen, a weak point is produced by the penetration of the point 11 into the pad 10 and causes the pad to burst immediately owing to the internal excess pressure. The escaping ink then flows into the space 12 surrounding the pad 10 and out of this space through the orifice 4" of the ring 4 into the reservoir wick 3. In this embodiment, for the purpose of producing a sealing effect between the push pin 7 and the insert element 6, a special seal 13 is formed, which seal, for example, may consist of a sleeve of yielding plastic.

The present invention has been described in detail by reference to a fibre-tipped pen. It will be appreciated, however, that the invention is applicable to other ink writing instruments, namely those whose writing tips are ball-points or conventional nibs.

I claim:

1. A writing instrument comprising: a body, a first ink reservoir wick therein, a writing tip at one end of said body, said tip having a plurality of capillary passages in communication with said first reservoir wick to receive ink therefrom, a second reservoir inside said body containing a reserve supply of ink for use when said first wick is exhausted, and means operatively associated with said second reservoir for causing said second reservoir to discharge its contents into said first reservoir wick, said means being a plunger element mounted in said body in a first position for movement relative thereto into a second position, and said second position indicating that said second reservoir had discharged its content into said first reservoir wick.

2. A writing instrument according to claim 1, wherein said second reservoir is a wick which is longitudinally slidable within said body, said wick being movable into contact with said first reservoir wick in response to actuation of said plunger element, thereby enabling its ink contents to flow into said first reservoir by capillary action.

3. A writing instrument according to claim 1, wherein said second reservoir is a wick which is immovably secured within said body, said wick being spaced from an adjacent end of said first reservoir wick, and said second reservoir wick being compressible in response to actuation of said plunger element, whereby release and delivery of its ink contents to said first reservoir wick is attained.

4. A writing instrument according to claim 1, wherein said second reservoir contains ink under pressure and a sharp point is provided at the inner end of said plunger element for penetrating said second reservoir when said plunger element is actuated, whereby said second reservoir bursts and releases its ink contents to said first reservoir wick.

5. A writing instrument according to claim 1, wherein said plunger element is mounted for sliding movement in the end of said body remote from said writing tip.

6. A writing instrument according to claim 1, wherein said plunger element is secured against inadvertent actuating movement in an initial, ready position thereof to prevent premature emptying of said second reser- V0".

7. A writing instrument according to claim 6, wherein said plunger element and said body include a mating groove and rib formation to secure said plunger element against inadvertent actuating movement, said groove and rib being separable when a predetermined actuating force is applied to said plunger element.

- 3,819,284 I 6 8. A writing instrument according to claim 6, wherein 9. A writing instrument according to claim 2, wherein said plunger element is cemented in said body, the cethe fibre density of said first reservoir wick is greater merit bond being rupturable when a predetermined acthan the fibre density of said second reservoir wick. tuating force is applied to said plunger element.

Claims

6. A writing instrument according to claim 1, wherein said plunger element is secured against inadvertent actuating movement in an initial, ready position thereof to prevent premature emptying of said second reservoir.

8. A writing instrument according to claim 6, wherein said plunger element is cemented in said body, the cement bond being rupturable when a predetermined actuating force is applied to said plunger element.

9. A writing instrument according to claim 2, wherein the fibre density of said first reservoir wick is greater than the fibre density of said second reservoir wick.