US3106909A - Ballpoint refill units - Google Patents

Description

Oct. 15, 1963 i R; R. REBO BALLPOINT REFILL UNITS Filed May 2, 1962 fiiq iki l2 INVENTOR.

RELNA R. REBO' FIG.9 BY

ATTORNEY United States Patent arenas? EALLPOHNT REFELL UNITS Reina R. Reba, (Irestwood, Mo, assignor to Ritepoint Pen and Pencil Company, St. Louis, Mo., a corporation of Mimonri Fiied May 2, 1962, Ser. No. $1,813 Unions. (Cl. Mo 42.4)

This invention relates in general to disposable ink cartridges for ballpoint pens and pencils and, more particularly, to an improved type of a vented plug for a ballpoint refill unit. 1

The ink solutions presently used in refill units for calpoint pens and ballpoint pencils have a very low viscosity and, therefore, extreme care must be taken in the design of the refill unit to prevent any of the liquid ink from unauthorizedly leaking out of the refill. This ink is usually a non-water soluble material and when accidentally spilled on clothing or furniture will cause a permanent stain that cannot be removed by any known bleach or cleaning agent.

It is, of course, necessary that each of these refill units be vented to the atmosphere in order that the ink within the refill tube will flow authorizedly out of a tubular channel formed within the writing point. In order to accomplish a continued authorized flow and yet prevent a spillage of the ink, the refill units presently existing have been formed with an open-ended long narrow stem which contains the writing ink. This ink usually has a sufliciently high surface tension so that it is maintained within the tubular container by capillary action. However, the amount of ink in the refill container is limited because the diameter of the container must be kept within a certain size range so that this capillary action will not be eliminated.

There have been some attempts to design large refill units of the so-called giant refill type, which contains a larger supply of ink and is provided with a vented cap at the open end. This cap must be designed within a high tolerance and a proper size air-venting aperture so'that the liquid ink within the refill unit will flow through the writing point. If the venting aperture is too small, the liquid ink will not flow, and if the venting aperture is too large there is a danger of the ink leakage. For this reason, these refill caps have not been particularly effective.

There have been other attempts to prevent leakage in large diameter ballpoint refills such as the use of the close-running ball. in this case, the ball will fall to the lower end of the tube when the ink tube is turned upside down so that its open end is pointed downwardly and thus acts as a closure valve to prevent the unauthorized escape of the liquid ink. Other attempts to prevent the unauthorized escape of the liquid ink resides in the use of convoluted ink tubes which have a greater length than the length of the normal pen or pencil barrel in which the tube is to be inserted. A number of attempts have also resided in the employment of plugs with internal baffling and with refillments having mechanical spring-type valve arrangements inside the tube for the control of leakage. However, all of these attempts have proved to be either commercially unfeasible or ineffective.

It is, therefore, the primary object of the present invention to provide a ballpoint refill unit which can be constructed with a large diametral size and does not require the use of an end cap.

It is another object of the present invention to provide a ballpoint refill unit of the type stated which is designed to contain a large quantity of ink solution.

It is a further object of the present invention to provide a ballpoint refill unit of the type stated which is properly vented so that the ink solution will adequately llow "ice (1-: through the writing point and yet will not leak through the open end of the refill unit.

It is an additional object of the present invention to provide a ballpoint refill unit of the type stated which has a long life and is economical to manufacture.

It is also an object of the present invention to provide a ballpoint refill unit of the type stated which can be manufactured in various sizes and shapes to fit almost all ballpoint pens and pencils.

With the above and other objects in view, my invention resides in the novel features of form, construction, arrangement, and combination of parts presently described and pointed out in the claims.

In the accompanying drawings (one sheet) FIG. 1 is a side elevational view of a ballpoint refill unit constructed in accordance with and embodying the present invention;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1;

FIGS. 3, 4, 5, and 6 are sectional views taken along lines 3-3, 4-4, 55, and 66, respectively, of FIG. 2;

FIG. 7 is a perspective view of a vented plug forming part of the present invention;

FIG. 8 is a perspective view of a vented plug forming part of the present invention, taken at a different angle; and

FIG. 9 is a sectional view taken along line 9-9 of FIG. 8.

Referring now in more detail and by reference characters to the drawing, which illustrates a preferred embodiment of the present invention, A designates a ballpoint refill unit comprising a tubular cartridge 1 having a diametrally reduced forward portion 2, reference being made to FIG. 2, and which is adapted for accommodating a conventional ballpoint insert 3. The diametrally reduced portion 2 is formed of a relatively short length which is just sufilcient to extend through the restricted space at the tapered writing point of a conventional ballpoint pen or pencil (not shown). The tubular cartridge 1 is internally sized to form a substantially cylindrical reservoir or chamber 4 for containing a solution of writing ink which is preferably though not necessarily provided at its rearward end 5 with a closure plug 6 having a shallow axial vent-slot 7, as shown in FIG. 1, if desired.

Disposed within the reservoir 4 near the open rearward end 5, is a flow-control plug 8 comprising a main cylindrical body 9 having end walls 1t 11. The length of the cylindrical body 9 is substantially small, relative to the overall length of the tubular cartridge l and is sized to fit snugly within the chamber 4, substantially as shown in PEG. 2. integrally formed with and extending rearwardly of the cylindrical body 9 is a coaxial hollow tube 12 which is centrally bored, and communicates with, an axial duct 13 formed centrally of the cylindrical body 9. The co axial tube 12 extends rearwardly from and is formed on the exact diametral center of the end wall 11. Extending forwardly of the cylindrical body 9 is a hollow tube 14 which is parallel to and eccentric with respect to the tube 12 overlapping the latter within the cylindrical body 9 in the formation of an offset opening 15 between the tubes 12, 14. By reference to FIG. 2, it can be seen that the tube 14 has a greatre length than the length of the tube 12. Furthermore, the tube 14 is positioned on the cylindrical body 9 in such manner that one portion of the peripheral wall of the tube 14 is axially tangent with a portion of the peripheral wall of the cylindrical body 9 so that the tube 14 lies flush, along such axial line of tangency, against a portion of the inner peripheral surface of the chamber 4.

It has been found, in connection with the present invention, that the aperture formed by the intersection of the internal ends of tubes 12, 14, is sufficient to provide an air vent which is required for proper ink flow and yet will maintain capillary action within the tube chamber 4 to prevent any authorized or undesired reverse flow of the ink through the tube.

In use, the plug 8 is inserted within the tubular cartridge 1 from the open end thereof after the cartridge 1 has been filled with a sufficient quantity of heavy viscosity ink of the type commonly used in ballpoint pens. The plug 8 is disposed within the chamber 4 until the rearward end of the coaxial tube 12 is recessed slightly from the open end 5 of the tubular cartridge 1. If the cartridge is upended the ink will not flow past the tube 14. It has been found by quality-control tests that if these tubular cartridges 1 are suspended so that the rearward end 5 is pointed downwardly, no ink leakage will occur.

It should be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the ballpoint refill units may be made and substituted for those herein shown and described without departing from the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A ballpoint refill unit comprising a tubular member open at one end, writing means disposed within the other end of said tubular member, a cylindrical plug disposed completely within said tubular member so that its outer wall snugly engages the interior wall of the tubular member in sealingwise contact, said plug having a central axial bore extending for approximately half of its axial length, said plug also having a diametrally offset axial bore for the remainder of its axial length and communicating with said central axial bore, a first tubular member connected to one end of said plug and extending outwardly therefrom, said first tubular member communicating with said central axial bore, and a second tubular member connected to the other end of said plug and extending outwardly therefrom, said second tubular member communicating with said diametrally offset axial bore.

2. A ballpoint refill unit comprising a tubular member open at one end, writing means disposed within the other end of said tubular member, a cylindrical plug disposed completely within said tubular member so that its outer wall snugly engages the interior wall of the tubular member in sealingwise contact, said plug having a central axial bore extending for approximately half of its axial length, said plug also having a diametrally offset axial bore for the remainder of its axial length and communicating with said central axial bore, a first tubular member connected to one end of said plug and extending outwardly therefrom, said first tubular member communicating with said central axial bore, and a second tubular member connected to the other end of said plug and extending outwardly therefrom, said second tubular member communieating with said diametrally olfset axial bore, said second tubular member being connected to said plug in such manner that a portion of its peripheral surface is flush with 4 the peripheral surface of said plug and engages the interior wall of said tubular member.

3. A vented plug for use in a ballpoint refill unit, said plug comprising a solid cylindrical member having a central bore extending a portion of its length, said member having a diametrally offset bore which is offset from the central bore and extends the remainder of its length, said central bore communcating with said diametrally oifset bore, and a tubular member connected to one end of said cylindrical member and extending outwardly therefrom, said tubular member communicating with said central bore.

4. A vented plug for use in a ballpoint refill unit, said plug comprising a solid cylindrical member having a central bore extending a portion of its length, said member having a diametrally offset bore which is offset from the central bore and extends the remainder of its length, said central bore communicating with said diametrally offset bore, a first tubular member connected to one end of said cylindrical member and extending outwardly therefrom, said first tubular member communicating with said central bore, and a second tubular member connected to the other end of said solid cylindrical member and extending outwardly therefrom, said second tubular member communicating with said diametrally offset bore.

5. A vented plug for use in a ballpoint refill unit, said plug comprising a solid cylindrical member having a central bore extending a portion of its length, said member having a diametrally offset bore which is offset from the central bore and extends the remainder of its length, said central bore intersecting with said diametrally offset bore at a common internal chamber having a diametral size which is smaller than the combined diametral sizes of the central bore and diametrally offset bore, a first tubular member connected to one end of said cylindrical member and extending outwardly therefrom, said first tubular member communicating with said central bore, and a second tubular member connected to the other end of said solid cylindrical member and extending outwardly therefrom, said second tubular member communicating with said diametrally otfset bore, said second tubular member being connected to said solid cylindrical member in such manner that a portion of its peripheral surface lies flush with the peripheral surface of said'solid cylindrical member.

References Qited in the file of this patent UNITED STATES PATENTS 2,505,211 Schiessel Apr. 25, 1950 2,521,285 Dearman Sept. 5, 1950 FOREEGN PATENTS 943,341 France Oct. 4, 1948 803,094 Germany Feb. 26, 1951 1,030,853 France Mar. 18, 1953 1,133,813 France Nov. 26, 1956

Claims (1)

1. 3. A VENTED PLUG FOR USE IN A BALLPOINT REFILL UNIT, SAID PLUG COMPRISING A SOLID CYLINDRICAL MEMBER HAVING A CENTRAL BORE EXTENDING A PORTION OF ITS LENGTH, SAID MEMBER HAVING A DIAMETRICALLY OFFSET BORE WHICH IS OFFSET FROM THE CENTRAL BORE AND EXTENDS THE REMAINER OF ITS LENGTH, SAID CENTRAL BORE COMMUNICATING WITH SAID DIAMETRICALLY OFFSET

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