US2481874A - Ball-point writing instrument - Google Patents

Description

Sept. 13, w49. R. w. RANDOLPH BALL-POINT WRITING INSTRUMENT r v I 2.1151551515 l Win/frgil!! Filed Oct. 5, 1945 fad/4, ff

Patented Sept. 13, 1949 BALL-POINT WRITING INSTRUMENT Robert W. Randolph, Milton, Wis., assigner to The Parker Pen Company, Janesville, Wis., a corporation of Wisconsin Application October 5, 1945, Serial No. 620,442

9 Claims.

. This invention relates to writing instruments and more particularly ball-point writing instruments of the kind wherein the writing point is propellable out of and retractable into the holder.

The immediate object is to provide a pushbutton operated propel-repel writing instrument-more especially of the ball-point varietywhich is highly dependable in operation and yet capable of being produced at low cost.

A more specic object is to provide in a ballpoint writing instrument a simple, inexpensive and reliable mechanism whereby successive manipulations of a single pushbutton or the like will effectuate both propulsion and retraction of the writing point.

A more comprehensive object is to provide a simple mechanism whereby two different kinds of operations can be brought about, consecutively and alternately, through repeated identical manipulations of a single pushbutton or the like.

A further object is to provide a pushbutton operated ball-point writing instrument of the retractable point variety wherein the ball point and ink reservoir are incorporated in a self-contained unit which can easily be withdrawn from the holder and replaced.

A preferred embodiment of the invention, as applied to a ball-point writing instrument, is illustrated in the accompanying drawing, wherein:

Fig. l is a longitudinal sectional view showing the writing point of the instrument in retracted position;

Fig. 2 is a View similar to Fig. l showing the writing point in its projected position;

Fig. 3 is a fragmentary view showing how the driving member of the propel-repel mechanism releases the latch to enable retraction of the writing point; -and Fig. 4 is a fragmentary sectional view showing the parts in the positions they assume when the driving member is fully depressed.

The instrument shown comprises an elongate, hollow holder I including a tapered metal tip member 2 attached to the front end of a tubular barrel consisting of two parts, 3 and 4, joined end-to-end Aat 5 through the medium of a threaded sleeve 6.

Disposed within the forward portion of the holder is a ball-and-cartridge unit 1 comprising an ink-reservoir portion 8 to the front of which is attached a forwardly extending feed tube 9 of small diameter terminating in a ball point IIl and having an ink passageway I I for conducting ink from the reservoir to the back of the ball point. Contained within the reservoir portion 8 Sis-a flexible sac I2 which constitutes the ink (Cl. 1Z0-42.03)

holder per se. Sac I2 may be made of thin rubber or the like and is filled with a viscous pastelike ink which flows by gravity through passageway II to the back of ball point Il) by whichA the ink is, in turn, conveyed to the writing surface. The exterior of sac I2 is always subjected to atmospheric pressure so that as the ink supply is used up the pressure within the sac remains atmospheric instead of going below that pressure as would otherwise be the case. When sac I2 is lled to normal capacity lit is expanded to occupy nearly all the space vin reservoir 8. It is shown in a condition of partial exhaustion.

Ball-and-cartridge unit 1 is reciprocable lengthwise, as a whole, within the holder, between the position in which it is shown in Fig. 1 and that in which it is shown in Fig. 2. In Fig. 1 the ball point is shown retracted into the bore I3, in which tube 9 is a sliding fit. Fig. 2, on the other hand, shows the ball-and-cartridge unit propelled forwardly to the writing position wherein ball point Il) is disposed beyond the iront end of tip member 2. Reservoir 8 includes an elongate thin metal tube I4 the diameter of which is reduced at its back end to grippingly engage the adjoining end of a plunger assembly which'comprises a driven member I5 and a driving member I6.

Driven member I 5 is a cylindrical rod or shaft slidable lengthwise in the bore of sleeve B. It is slotted at I5a at its front end and expanded to grippingly engage tube I 4; reduced in diameter to form an annular shoulder I1; and slotted lengthwise at I8 to form a gripping telescopic engagement with the bore I9 of driving member I6.

Integral with sleeve 5 are two or more backwardly extendingspring arms 20 and 2l having at their free ends, respectively, two latch. members 22, 23 which are biased inwardly bythe spring arms and are .thus capable of engaging shoulder I1, as shown in Fig. 2, to prevent retraction of driven member I5.

Driving member I6 is continuously urged backwardly by a coil spring 24 conned between an upper sleeve portion Ea and a flange Ilibon the driving member IB. -A bushing 29 screwed into the back end of the holder servesas a stop to limit the extent of backward movement of said driving member by engaging the flange IBb thereon.

With the writing point and plunger assembly retracted as per Fig. 1, the back end Ilia of driving member I6 projects out of the holder to form a manually operable pushbutton. When this pushbutton is depressed driving member I6 is.

of course, propelled forwardly against the opposition of spring 24, carrying with it driven member I5 and ball-and-cartridge unit l. This is due to the frictional coupling between driven member I5 and driving member I6 effected by the close tting telescopic interengagement of those two members.

When driven member I5 together with the balland-cartridge unit has been propelled forwardly to the extent shown in Fig. 2, latch members 22 and 23 are forced inwardly by their respective spring arms to positions behind shoulder I'I and, if pushbutton Ita is not then further depressed, said driven member and said ball-and-cartridge unit will remain locked in their forward positions, in which the instrument is ready for use. Assuming that the pushbutton is then` released, driving member I5 will retract under the pressure oi spring 24 notwithstanding the frictional adhesion between it and driven member I 5. This is due tothe fact that spring 24 is strong enough toovercome the restraining force of the irictional coupling.

' The maximum possible forward movement of driven member I5 is limited by a stopscrew 25, the ,3

inner end of which engages the back end of a longitudinal slot 25 in said member. If, then, with the instrument in the adjustment of Fig. 2, pushbutton Ilia is depressed as far as it will go, driven member I5 will be propelled forwardly to the limit permitted by stopscrew 25, and driving member i6 will continue moving forwardly until its front end contacts shoulder I1, whereupon member I6 can travel forwardly no farther. But during this additional forward movement of driving member I6 its front end engages the acutely angular surfaces 2l' and 28 of latch members 22' and 23, respectively, as shown in Fig. 3, and forcesy said latch members outwardly beyond the path of shoulder I1. pushbutton is released, the` entire plunger assembly together with the ball-and-cartridge unit will quickly move back to the retracted position of Fig. 1. During the latter movement latch members 22' and 23 cannot move into the path of shoulder I1 because the front end of driving member t6 remains in contact with said shoulder and there is no space therebetween to permit entry of the latch members.

By disconnecting the two parts of thev barrel at joint- 5, the ball-and-cartrldge unit can easily be Withdrawn froml the front portion of the holder, whereupon it can. be pulled oil the end of driven member I5, and replaced by another unit. Re-

placements are thus made whenever the ink supply needs replenishing; and a new ball point is incidentally provided at the same time', since that constitutes an integral part o1' the replacement unit.

Manifestly, the novel propelling and retracting fr? mechanism illustrated and described is capable of many uses outside the environment in which it is here shown.

li claim:

1. A mechanism comprising a driving member and a driven member, both movable along a given path,v said members being fricticnally connected together, the frictional coupling therebetween being of such strength as to cause said driven member to follow the movements of said driving member along said path except when said driven member is restrained as hereinafter prescribed, a latch operative to engage said driven member when the latter has been moved to a predetermined extent in one direction along said path If, thereupon, the

d by said driving member, said latch being effective when so engaged to prevent movement of said driven member in the opposite direction, means for limiting the extent of movement of said driven member along said path in said one direction, said driving member being forcibly movable in said opposite. direction nothwithstanding the latching o said driven member said driving member being operative upon movement in said one direction f to release said latch and further operative, conjointly with said driven member, following such release and a continuing movement of said members in said one direction to the fullest extent permitted by said limiting means, to hold said i latchy released, thereby enabling said driven member thereafter to follow said driving member in said opposite direction to the full extent of its travel in said opposite direction.

2. A mechanism comprising a driving member and a driven member movable together along a given path and frictionally connected together, the frictional coupling between said members being oi such strength as to cause said driven member to follow the movements of said driving member along said path except when said driven member is restrained as hereinafter prescribed, a spring continuously urging said driving member in one direction along said path and communicating its force to said driven member only .A through said driving member and said frictional coupling,v a latch operative to engage said driven member when said driven member is moved in one direction along said path to a predetermined position, said latch being eiective to restrain said driven member against movement in the opposite direction, said spring being strong enough to overcome said frictional coupling and thus to move said driving member to a limited extent in said opposite direction independently of said driven member while said driven member continues restrained by said latch, means for limiting the movement of said driven member in said one direction, said. driving. member being operative upon movement in said one direction to release isaid latch and thereby enable said driven member to follow said driving member to the full extent of the latters. subsequent movement in said opposite direction.

3. A mechanism comprising a driving member and a driven member telescopically connected t0- gether end-to-end and frictionally coupled through their mutual telescopic engagement, said members being movable along a given path, the frictional coupling therebetween being of such strength as to cause said driven member to follow the movements of said driving member along said path except when said driven member ls restrained as hereinafter prescribed, meansl for limiting the movement in one direction of said driven member, a latch operative to engage said driven member when the latter has been moved in said one direction to a predetermined extent, which is less than the maximum movement in said one direction permitted by said limi-ting means, said latch being effective, when so engaged, to restrain said driven member against movement in the opposite direction, said driving member being forcibly movable in the opposite direction notwithstanding the latching of said driven member, said driving member being operative when moved in said one direction to the full extent permittedby said limiting means to release said latch and hold the same released throughout a subsequent movement of said members in said opposite direction, which subsequent movement is of suflicient extent to carry said driven member beyondV the point where it can be engaged by `said latch.

4. A mechanism comprising a driving member and a driven member telescopically connected together end-to-end and frictionally coupled through their mutual telescopic engagement, said members being movable along a given path, the frictional coupling therebetween being of such strength as to cause said driven member to follow the movements of said driving member along said path except when said driven member is restrained as hereinafter prescribed, means for limiting the movement of said driven member in one direction along said path, a spring continuously urging said driving member in the opposite direction along said path, a latch operative to engage said driven member when the latter has been moved in said one direction to a predetermined extent which is less than the maximum movement in said one direction permitted by said limiting means, said latch being effective, when so engaged, to restrain said driven member against movement in the opposite direction,l said driving member being forcibly movable in the opposite direction by said spring notwithstanding the latching of said driven member, said latch having a surface disposed at an acute angle to said path, said driving member being operative when moved in said one direction to the full extent permitted by said limiting means to engage and act upon said surface as a cam and thereby force said latch into a position wherein it is ineffective to restrain said driven member, and further operative to hold said latch in said ineffective position during a subsequent movement of said members in said opposite direction1 which subsequent movement is of suicient extent to carry said driven member beyond the point where it can be engaged by said latch.

5. In a writing instrument, an elongate, hollow holder having a bore opening at its front end, a ball-and-cartridge unit mounted within and reciprocable lengthwise of said holder, said unit comprising an ink reservoir vand awriting ball connected to the front end thereof, said ball becomprising a driving member and a driven member, both movable along a given path lengthwise of said holder, said members being frictionally connected together, the frictional coupling therebetween being of such strength as to cause said driven member to follow the movements of said driving member along said path except when said driven member is restrained as hereinafter prescribed, a latch operative to engage said driven member when the latter has been moved to a predetermined extent in the forward direction along said path by said driving member, said latch being effective when so engaged to prevent movement of said driven member in the backward direction, means for limiting the forward movement of said driven member, said driving member being forcibly movable in the backward direction notwithstanding the latching of said driven member, said driving member being operative upon forward movement to release said latch and further operative, conjointly with said driven member, following such release and additional forward movement to the extent permitted by said limiting means, to hold said latch released, thereby enabling said driven member thereafter to follow said driving member to the full extent of its backward travel.

6. In a writing instrument, an elongate, hollow holder having a bore opening at its front end and having a chamber adapted to receive a ball-andcartridge unit which is reciprocable lengthwise therein, said unit comprising an ink reservoir and a writing ball connected to the front end thereof, said ball being retractable into said bore by a backward movement of said unit and propellable out of the front end of said bore into writing position by a forward movement of said unit, a plunger disposed in the bore of said holder andadapted for connection to the rear end of said unit for propelling and retracting the same, the back end of said plunger projecting out of said holder to form a manually operable pushbutton, said plunger comprising a driving member and a driven member telescopically connected together end-to-end and frictionally coupled through their mutual telescopic engagement, said driving member being situated to the rear of said driven member, said members being movable along a path lengthwise of said holder, the frictional coupling therebetween being of such strength as to cause said driven member to follow the movements of said driving member along said path except when said driven member is restrained as hereinafter prescribed, means for limiting the forward movement of said driven member along said path, a spring continuously urging said driving member backwardly along said path, a latch operative to engage said driven member when the latter has been moved forwardly to a predetermined extent which is less than the maximum forward movement permitted by said limiting means, said latch being effective, when so engaged, to restrain said driven member against backward movement, said driving memn ber being movable backwardly by said spring notwithstanding the latching of said driven member and notwithstanding the frictional adhesion between said members, said latch having a surface disposed at an acute angle to said path, said driving member being operative when moved forwardly to the full extent permitted by said limiting means to engage and act upon said surface as a cam and thereby force said latch into a posi- `tion wherein .it is ineffective to restrain said driven member, and further operative to hold said latch in said ineffective position during a subsequent backward movement of said members, which subsequent movement is of sufficient extent to carry said driven member beyond the point where it can be engaged by said latch.

7. In a ball-point writing instrument, an elongate, hollow holder having a bore opening at its front end, a ball-and-cartridge unit mounted within and reciprocable lengthwise of said holder, said unit comprising an ink reservoir and a ball point connected to the front end thereof, said ball being retractable into said bore by a. backward movement of said unit and propellable out of the front end of said bore into writing position by a forward movement of said unit, a plunger disposed in the bore of said holder at the rear of said unit and connected to said unit for propelling and retracting the same, the back end of said plunger projecting out of said holder to form a manually operable pushbutton, said plunger comprising a driving member and a driven' member movable together along `a path lengthwise of said l'wlder and frictionally connected together, the frictional coupling betweenV saidm'embers being of such strength as to cause said driven member to follow the movements of said driving member along said pathzexcept when said driven member is restrained as hereinafter prescribed, said driving .member being situated to the rear of said driven member in end-to-end relation thereto, a spring continuously urging said driving member 'backwardly along said path and communicating its force to said driven member only through said driving member and said frictional coupling, a latch operative to engage said driven member when said driven member is moved forwardly along said path to a predetermined position, said latch being eiective to restrain said driven member against backward m'ovement, said spring being strong enough to overcome the frictional adhesion between said members and thus to move said driving member backwardly to a limited extent `independently of said ydriven member while the latter continues restrained by said latch, means for limiting the forward movement of said driven member, said driving member being operative upon a full forward movement to release said latch and to hold the same released, thereby enabling said driven member to follow said driving member to the full extent of the latters subsequent backward movement.

8. A ball-point writing instrument comprising a casing having readily detachable front and rear sections which when joined together provide a continuous elongated casing, a writing unit mounted wholly within said forward casing section and including a ball-writing point and a coupling element, said unit being self-contained and mounted in said forward section for sliding movement forwardly to project the ball point from said forward casing section and rearwardly to retract it Within .said forward casing section, and a self-contained projecting and retracting unit mounted wholly within said rear section and including a coupling element adapted to operably connect with said first-named coupling element, and means for moving said writing unit forwardly to project said ball point, for holding said writing unit in its forward position, for releasing said writing unit from its forward and held position, and for returning it to its retracted position to retract said ball point within its casing section, said projecting and retracting unit being wholly self-contained with said rear casing section and being constructed and arranged to operably engage its said coupling element with the said coupling element of the writing unit upon connection of said casing sections and to expose said writing unit for removal thereof by disengagement of said coupling lelements after separation of said casing sections.

9. A ball-point writing instrument comprising a casing having readily detachable front and rear sections which when joined together provide a continuous elongated casing, an ink feed and writing unit mounted wholly within said forward easing section and including an ink reservoir, a ball-writing point, ink feed means connecting said ink Yreservoir with said ball point, and a coupling element, said unit being self-contained and mounted in said forward section for sliding movement forwardly to project the ball point from said forward casing section and rearwardly to retract it within said forward casing section, and a self-contained projecting and retracting u-nit mounted wholly within said rear section and including a coupling element adapted to operably connect with said first-named coupling element, means for moving said ink feed and writing unit forwardly to project said ball point, means for locking said ink feed and writing unit in its forward position, means for releasing said ink feed vand writing unit from its forward and locked position, and means for returning said ink feed and writing unit to its retracted position to retract said ball point within its casing section, said projecting and retracting unit being wholly self-contained with said rear casing section and being constructed and arranged to operably engage its said coupling element with the said coupling element of the ink feed and writing unit upon connection of said casing sections and to expose said writing unit for removal thereof by disengagement of said coupling elements after separation of said casing sections.

ROBERT W. RANDOLPH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 378,897 Myers Mar. 6, 1888 1,947,282 Theis Feb. 13, 1934 2,367,892 Schallis Jan. 23, 1945 2,398,548 Moore Apr. 16, 1946 FOREIGN PATENTS Number Country Date 210,230 Germany May 25, 1909 537,039 Great Britain June 6, 1941

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