US3630629A - Mechanical writing instrument - Google Patents

Abstract

A mechanical writing instrument in which a carrier supporting an ink cartridge or the like is received by and threadably engages a driver tube rotatably positioned on a sleeve by a snapring. Interengageable means provide a connection between the carrier and the sleeve which permits relative axial movement therebetween while preventing rotary movement in response to rotation of the driver tube relative to the sleeve alternately to extend and retract the cartridge with reference to the sleeve. The assembly may be completed by a decorative two-part casing and a nose through which the point of the writing instrument may protrude.

Description

llnited States Patent 72] Inventor Gino Carmen DiSpirito Hasbrouch Heights, NJ. [21] Appl. No. 885,421 [22] Filed Dec. 16, 1969 [45] Patented Dec. 28, 1971 [73] Assignee Kreisler Manufacturing Corporation North Bergen, NJ.

[54]MECHANICAL WRITING INSTRUMENT 18 Claims, 1 1 Drawing Figs.

[52] U.S.Cl 401/116 [51 Int. Cl B431: 24/06 [50] Field ofSearc 40l/68,78, l 16 [56] References Cited UNITED STATES PATENTS 3,272,184 9/1966 Crowley 401/116 3,436,160 4/1969 Lanoie ABSTRACT: A mechanical writing instrument in which a carrier supporting an ink cartridge or the like is received by and threadably engages a driver tube rotatably positioned on a sleeve by a snapring. lnterengageable means provide a connection between the carrier and the sleeve which permits relative axial movement therebetween while preventing rotary movement in response to rotation of the driver tube relative to the sleeve alternately to extend and retract the cartridge with reference to the sleeve. The assembly may be completed by a decorative two-part casing and a nose through which the point of the writing instrument may protrude.

PATENTED names 191;

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67/70 .ZZ'Sk/r/TO I'TTORNEYS PATENTED DEC28 I97:

SHEET 2 OF 2 0 5 W N? R WW 0 m5 Km [MM MECHANICAL WRITING INSTRUMENT BACKGROUND OF THE INVENTION There are known in the prior art writing instruments of the type in which an ink cartridge is adapted to be shifted between a retracted position at which its point is housed by the nose of the assembly and a writing position at which the point protrudes beyond the end of the nose. The less expensive mechanisms are arranged so that the cartridge can be snapped axially into writing position against the action of a spring and then retracted in response to a second operation of the actuating element such as push button or the like. Instruments of this type have relatively short life and in many instances are not as appealing to customers as are instruments of the type wherein the writing point is exposed and retracted in response to relative rotary movement between two parts of the assembly.

In writing instruments of the type wherein the point is extended and retracted in response to relative rotary motion between parts of the assembly, it is desirable that the rotary motion required to move the point between the two positions be relatively small. Further, it is necessary that the point he firmly held in the writing position so that it will not back off or entirely retract in response to pressure on the point. Many attempts have been made in the prior art to provide a writing instrument of this type. The most successful attempts have involved structures employing a multiplicity of parts. Owing to the large number of parts making up the mechanisms they are complex and are consequently expensive to manufacture. In addition they are inherently subject to mechanical failures and are not readily repairable.

I have invented a mechanical writing instrument which overcomes the defects of writing instruments of the type in which the point is extended or retracted in response to a rotary movement. My mechanism employs a surprisingly small number of parts. It is simple both in construction and in operation. It is relatively inexpensive to manufacture. It is rugged and has a long life.

SUMMARY OF THE INVENTION One object of my invention is to provide a mechanical writing instrument which overcomes the defects of instruments of the prior art of the type in which the point is extended and retracted in response to a rotary movement.

Another object of my invention is to provide a mechanical writing instrument of the rotatable type which employs a minimum number of parts.

A further object of my invention is to provide a mechanical writing instrument which is simple in construction and in operation.

Still another object of my invention is to provide an mechanical writing instrument which is rugged and which has a long life.

Yet another object of my invention is to provide a mechanical writing instrument which is inexpensive to manufacture.

Other and further objects of my invention will appear from the following description.

In general my invention contemplates the provision of a mechanical writing instrument in which a driver tube rotatably positioned on a sleeve by a snap ring located in a groove on the sleeve threadably receives an ink cartridge carrier connected to the sleeve for rotary movement therewith and for axial movement relative thereto. In response to relative movement between the driver tube and the sleeve in one direction the point of the ink cartridge is exposed and in response to an opposite relative rotary movement of the driver tube and sleeve the point is retracted. My assembly may be provided with a decorative casing held in position on the sleeve by a nos and a cap frictionally received by the operating mechanism assembly.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings which form part of the instant specification and which are to be read in conjunction herewith and in which like reference numerals are used to indicate like parts in the various views:

FIG. I is a perspective view of my mechanical writing instrument with the cap showing in phantom.

FIG. 2 is an exploded perspective view illustrating the parts of the operating mechanism of my improved mechanical writing instrument.

FIG. 3 is a longitudinal sectional view of my mechanical writing instrument illustrating the relative positions of the parts with the point extended.

FIG. 4 is a sectional view of my mechanical writing instrument taken along the line 4-4 of FIG. 3 and drawn on an enlarged scale.

FIG. 5 is a sectional view of my mechanical writing instrument taken along the line 5-5 of FIG. 3 and drawn on an enlarged scale.

FIG. 6 is a sectional view of my mechanical writing instrument taken along the line 6-6 of FIG. 3-and drawn on an enlarged scale.

FIG. 7 is an exploded perspective view of the operating mechanism of a modified form of mechanical writing instrument.

FIG. 8 is a sectional view of the form of my writing instrument illustrated in FIG. 7 showing the mode of operation of a part of the mechanism.

FIG. 9 is a perspective view of yet another form of driver tube which I might employ in my mechanical writing instrument.

FIG. 10 is a fragmentary perspective view illustrating a further embodiment of my means for retaining cap on my mechanical writing instrument.

FIG. 11 is a sectional view with parts removed illustrating the cap retaining means shown in FIG. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings my mechanical writing instrument indicated generally by thereference character 10 includes acarrier 12 having an elongated body provided with anaxial bore 14. One end of thecarrier 12 is provided withexternal threads 16 adapted to be engaged byinternal threads 18 of afitting 20 which supports anink cartridge 22 or the like having apoint 24. Preferably I provide fitting 20 with aserrated head 24a to facilitate placing of thecartridge 22 in thecarrier 12 as required.

I form the central portion of thecarrier 12 with an externalhelical groove 26 having a low pitch so that only a relatively small rotary movement will produce the desired movement of the ink cartridge in a manner to be described. I form the end of thecarrier 12 remote from thethreads 16 with a plurality of axially extendingsplines 28 for a reason which will be apparent from the description given hereinafter.

Myinstrument 10 as a second element of the operating mechanism thereof includes anelongated sleeve 30 formed with abore 32 through which thecartridge 22 extends. On end of mysleeve 30 is provided with a multiplicity of internal axially extendinggrooves 34 adapted to receive thesplines 28 to provide a connection between the carrier and thesleeve 30 which permits relative axial movement therebetween while preventing relative rotary motion. An externalannular groove 36 along the length ofsleeve 30 is adapted to receive aresilient snap ring 38 provided with awall slit 40. While I have shown theslit 40 as running obliquely it might as well run axially of the ring if desired. Preferably I taper the and 42a ofsleeve 30 to facilitate assembly of the snap ring on the sleeve for a reason which will be described hereinbelow.

The three parts of the operating mechanism of my writing instrument thus far described, thecarrier 12, thesleeve 30 and thering 38. may be formed of any suitable material such for example as a suitable synthetic resin. Preferably the material is one which has good dimensional ability. I have found that Delrin" which is the registered trademark of E. I. DuPont De Nemours & Co. for an acetal thermoplastic resin having high strength and stiffness, toughness and resilience over a wide temperature range as well as good dimensional stability and excellent bearing characteristics, is eminently suited for use as a material from which I may make theparts 12, 30, and 38.

The fourth and last element of the operating mechanism of my writing instrument is thedriver tube 42 which may be formed from metal and provided with an internalhelical bead 44 having the same pitch as thegroove 26 and extending over a small portion of the length oftube 42 intermediate its ends. I formtube 42 adjacent its top with aninternal shoulder 46 which limits movement of the carrier in one direction in a manner to described. Further as will be described hereinbelow in the course of assembling the operating mechanism of my instrument I provide the end oftube 42 remote fromshoulder 46 with an inwardly extendingflange 48.

The four parts thus far described complete the operating assembly of my instrument and are all the parts which are necessary to produce movement of thecartridge 22 between extended and retracted positions in response to relative rotary movement betweendriver tube 42 and thesleeve 30. For decorative purposes the instrument is completed by ashell 50 adapted to be slipped oversleeve 30 and into engagement withring 38 with a relatively high frictional force. Anose 52 is provided withthreads 54 which permit it to be threaded into the lower threaded end ofsleeve 30 to force theshell 50 into position onring 38. Acap 56 which may be provided with apocket clip 58 frictionally fits on thedriver tube 42 so that it can be relatively readily removed to permit replacing ofcartridge 22 and then replaced. Adecorative spacer ring 60 may be disposed betweenshell 50 andcap 56.

If desired I may form the driver tube with an inwardly directedprojection 62 in the region of thebead 44 to increase the frictional force between thecarrier 12 and thetube 42 to prevent too easy relative rotation therebetween. Further, if desiredtube 42 may have a plurality of outwardly directedprojections 64 to provide a relatively high-frictional force betweencap 56 and the driver tube to ensure that the tube turns with the cap when the latter is rotated.

In assembling my writing instrument, I first secure thecartridge 22 to thecarrier 12 by passing thecartridge 22 throughbore 14 and threading the fitting onto thethreads 16. Next, thesleeve 30 is assembled with thecarrier 12 by inserting thesplines 28 into thegrooves 34. When that has been donedriver tube 42 is telescoped over the assembly ofcarrier 12 andsleeve 30 by moving the end of the tube upon whichflange 48 is to be formed over thehead 24 of fitting 20 and threadingbead 44 withgroove 26 until the end oftube 42 remote fromshoulder 46 isadjacent groove 36. The end of the sleeve is upset to formflange 48 ingroove 36. It will be appreciated that thegroove 36 is sufficiently wide to permit the formation offlange 48 in a relatively expeditious manner. Next, thesplit ring 38 is slid up along thesleeve 30 until it rides intogroove 36 to holdflange 48 against the upper edge of the groove. The operating mechanism of my instrument is now complete. To finish the assembly thecasing 50 is slid onto thesleeve 30 and up over thesplit ring 38. When this operation has continued to a point at which the lower end ofsleeve 30 is accessible to the threaded portion ofnose 52 the nose is threaded in place. Now cap 56 is placed on the assembly.

Referring now to FIGS. 7 and 8 I have shown a modified form of my writing instrument in which like parts to those illustrated in the form shown in FIGS. 1 to 6 are indicated by the same reference numbers. Thecarrier 12 and thecartridge 22 are the same as in the form of my writing instrument illustrated in FIG. 1 to 6. Thesleeve 30 is slightly modified in that it is provided with anannular groove 66 between its endadjacent carrier 12 and thesnap ring groove 36.Groove 66 is adapted to receive a clutchingspring 68 which is formed of any suitable material such for example as stainless steel and which may be coated with a material such as Teflon" which is the registered trademark of E. I. DuPOnt De Nemours & Co. for tetraflouroethylene synthetic resin, or coated with polyethylene, resin resin or the like. Preferably I form the clutch 68 with a generally triangular configuration so that when it is assembled ingroove 66 the inner surfaces of its legs engage the base ofgroove 66. The dimensions of the clutching spring are such that before assembly the apices hereof protrude slightly beyond the edges of thegroove 66.

Thedriver tube 70 of this form of my device is similar todriver tube 42 but has respective outwardly directedribs 72 extending axially of the reduced end portion thereof. These ribs cooperate with aferrule 74 assembled within thecap 56 to insure a firm engagement between the cap and thedriver tube 70. It will be appreciated that where I use the ferrule 74 I need not provide theprojections 64 described hereinabove.

In assembling the form of my writing instrument illustrated in FIG. 7 the clutchingspring 68 is assembled ingroove 66 andsplines 28 are engaged in thegrooves 34. This assembly then is slid into thedriver tube 70 upon whichflange 48 has not yet been formed. In order to facilitate entry of thespring 68 into the bore of tube 70 I provide a special tool (not shown) having a tapered inner bore which is adapted to be slipped oversleeve 30 to a position at which it distortsspring 68 to permit it to entertube 70. When the clutching spring has moved into the tube the assembly ofcarrier 12 andsleeve 30 is pushed sufficiently far into thetube 70 to permit formation of the retainingflange 48 in thegroove 36. Before formation of theflange 48 the tool is of course removed. Next. a split ring having straight wall cut 82 is slid oversleeve 30 and into thegroove 36. The apices of thespring 68 engage the inner surface oftube 70 to provide the required torque for relative rotation betweentube 70 andsleeve 30 for proper operation of the instrument.Ferrule 74 may be assembled incap 56 by any suitable means and thenhousing 50 andcap 56 together with thetip 52 may be applied to complete the assembly.

Referring to FIGS. 10 and II in a further form ofmy means for releasably holdingcap 56 in position on the tube 70 I provide a reduceddiameter end portion 88 oftube 70 with spacedslots 90 extending in the direction of the length of the tube. For example I may provide threeslots 90 equally spaced aroundportion 88 by Abushing 92 formed from a suitable material such as nylon has elongatedinternal ribs 94 spaced correspondingly toslots 90 and adapted to engage in the slots when thebushing 92 is slipped ontoportion 88. Elongatedexternal ribs 96 at locations corresponding toribs 94 are adapted frictionally to retain thecap 56 when it is slipped over the end oftube 70. It will be appreciated that the pairs ofribs 94 and 96 may flex inwardly when this operation takes place.

In operation of the form of my mechanical writing instrument illustrated in FIGS. 1 to 6 in response to counterclockwise rotation ofcap 56 anddriver tube 42 relative tocasing 50 andsleeve 30 as viewed from the top of theinstrument l0 carrier 12 andcartridge 22 move to the right as viewed in FIG. 3 until the end ofcarrier 12adjacent threads 16 engagesshoulder 46. This is the limit of the retracted movement of the carrier and cartridge illustrated in broken lines in FIG. 3. Upon reverse relative movement of thecap 56 andtube 42 relative tocasing 50 andsleeve 30carrier 12 andcartridge 22 move to the left to the limit permitted bysplines 28 andgrooves 34 which is the limit of the extended position of the cartridge. The operation of the form of my invention illustrated in FIGS. 7 and 8 is substantially the same.

It will be seen that I have accomplished the objects of my invention. I have provided a mechanical writing instrument which overcomes the defects of mechanical writing instruments of the type which are operated in response to rotary movement. My instrument includes a minumum of parts for the operating mechanism thereof. It is rugged in construction and has a long life. It is simple in construction and operation. It is inexpensive to manufacture.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. It is further obvious that various changes may be made in details without departing from the spirit of my invention. It is, therefore, to be understood that my invention is not to be limited to the specific details shown and described.

Having thus described my invention, what I claim is:

1. An operating mechanism for a writing instrument including combination, carrier, an elongated writing element having a point supported on said carrier for movement therewith, a sleeve, means coupling said sleeve to said carrier for rotary movement therewith and for axial movement relative thereto, a driver tube, positively interengaging elements on said driver tube and on said sleeve for connecting said driver tube to said sleeve for rotary movement relative thereto while restraining said driver tube against axial movement relative to said sleeve, said writing element extending through said sleeve, and interengageable means on said driver tube and on said carrier for moving said carrier axially in response to rotary movement of said driver tube on said sleeve to move said writing element between an extended position and a retracted position.

2. An operating mechanism as inclaim 1 including means on said driver tube for limiting the movement of said carrier to said retracted position.

3. An operating mechanism as inclaim 2 in which said limiting means is a shoulder on said driver tube engaged by said carrier in said retracted position.

4. An operating mechanism as inclaim 1 in which said interengageable means comprises a helical groove in one of the carrier and driver tube and a helical bead on the other of the carrier and driver tube.

5. An operating mechanism as inclaim 1 in which said coupling means comprise an axially extending spline on one of the carrier and sleeve and an axially extending groove in the other of the carrier and sleeve for receiving said spline.

5. An operating mechanism as inclaim 1 in which said coupling means comprise a plurality of spaced splines formed on one end of one of the carrier and sleeve, and a plurality of correspondingly spaced grooves in the associated end of the other of said carrier and sleeve.

7, An operating mechanism as inclaim 1 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed annular flange on an end of said driver tube located in said groove and a resilient snap ring disposed in said groove for positioning said flange in said groove.

8. An operating mechanism as inclaim 1 in which said coupling means comprises an axially extending spline on one of said carrier and sleeve and an axially extending groove in the other of said carrier and sleeve for receiving said spline and in which said interengageable means comprises a helical groove in one of the driver tube and carrier and a helical bead on the other of the driver tube and carrier for riding in said groove.

9. An operating mechanism as in claim 8 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed flange on one end of said driver tube, and a snap ring in said groove for holding said flange against an edge of said groove.

10. An operating mechanism as in claim 9 including first means for limiting the movement of said carrier to the retracted position of said element and second means for limiting the movement of said carrier to the extended position of said element.

11. An operating mechanism as inclaim 10 in which said first limiting means comprises a shoulder formed on said tube for engagement by said carrier and in which said second limiting means comprises said spline and axial groove.

12. A mechanical writing instrument including in combination, a carrier having a longitudinally extending bore, an elongated writing element having a point, means detachably mounting said element on said carrier for movement therewith, a spiral track formed in the outer surface of said carrier along a portion of the length thereof, a sleeve having a longitudinally extending bore, aid element extending through said sleeve bore, a spline formed at one end of one of the carrier and sleeve, an axially extending groove formed in an end of the other of he carrier and sleeve for receiving said spline to couple said carrier to said sleeve for rotary movement therewith and for axial movement relative thereto, a driver tube having an Internal helical bead, said tube adapted to receive said carrier with said bead located in said track, means forming an annular groove in the outer surface of aid sleeve, an inwardly directed flange on an end of said tube disposed in said groove, a resilient snap ring in said groove for positioning said flange against an edge of said groove, and an elongated casing adapted to he slid over said sleeve and into frictional engagement with said snap ring.

13. A writing instrument as inclaim 12 including a nose secured to said sleeve for holding said casing in position on said assembly.

14. A writing instrument as inclaim 12 including a cap frictionally supported by said tube for rotation therewith.

15. A writing instrument as inclaim 12 including means for increasing the frictional force between said driver tube and said carrier.

16. A writing instrument as inclaim 12 including means forming a second annular groove in the outer surface of said sleeve, said second groove being located between said first annular groove and the end of said sleeve adjacent said carrier and a spring clutch element disposed in said second annular groove for engaging the inner surface of said tube.

17. A writing instrument as inclaim 16 in which said spring clutch is generally triangularly shaped element of resilient material.

18. A writing instrument as inclaim 12 including means forming spaced slots in the wall of said driver tube adjacent the other end thereof, a bushing having internal ribs spaced correspondingly to said slots, said bushing adapted to be slipped over said other end to locate said ribs in said slots, external ribs on said bushing at locations corresponding to the locations of said internal ribs, and a cop frictionally received by said external ribs.

Claims (18)

1. An operating mechanism for a writing instrument including combination, carrier, an elongated writing element having a point supported on said carrier for movement therewith, a sleeve, means coupling said sleeve to said carrier for rotary movement therewith and for axial movement relative thereto, a driver tube, positively interengaging elements on said driver tube and on said sleeve for connecting said driver tube to said sleeve for rotary movement relative thereto while restraining said driver tube against axial movement relative to said sleeve, said writing element extending through said sleeve, and interengageable means on said driver tube and on said carrier for moving said carrier axially in response to rotary movement of said driver tube on said sleeve to move said writing element between an extended position and a retracted position.

2. An operating mechanism as in claim 1 including means on said driver tube for limiting the movement of said carrier to said retracted position.

3. An operating mechanism as in claim 2 in which said limiting means is a shoulder on said driver tube engaged by said carrier in said retracted position.

4. An operating mechanism as in claim 1 in which said interengageable means comprises a helical groove in one of the carrier and driver tube and a helical bead on the other of the carrier and driver tube.

5. An operating mechanism as in claim 1 in which said coupling means comprise an axially extending spline on one of the carrier and sleeve and an axially extending groove in the other of the carrier and sleeve for receiving said spline.

6. An operating mechanism as in claim 1 in which said coupling means comprise a plurality of spaced splines formed on one end of one of the carrier and sleeve, and a plurality of correspondingly spaced grooves in the associated end of the other of said carrier and sleeve.

7. An operating mechanism as in claim 1 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed annular flange on an end of said driver tube located in said groove and a resilient snap ring disposed in said groove for positioning said flange in said groove.

8. An operating mechanism as in claim 1 in which Said coupling means comprises an axially extending spline on one of said carrier and sleeve and an axially extending groove in the other of said carrier and sleeve for receiving said spline and in which said interengageable means comprises a helical groove in one of the driver tube and carrier and a helical bead on the other of the driver tube and carrier for riding in said groove.

9. An operating mechanism as in claim 8 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed flange on one end of said driver tube, and a snap ring in said groove for holding said flange against an edge of said groove.

10. An operating mechanism as in claim 9 including first means for limiting the movement of said carrier to the retracted position of said element and second means for limiting the movement of said carrier to the extended position of said element.

11. An operating mechanism as in claim 10 in which said first limiting means comprises a shoulder formed on said tube for engagement by said carrier and in which said second limiting means comprises said spline and axial groove.

12. A mechanical writing instrument including in combination, a carrier having a longitudinally extending bore, an elongated writing element having a point, means detachably mounting said element on said carrier for movement therewith, a spiral track formed in the outer surface of said carrier along a portion of the length thereof, a sleeve having a longitudinally extending bore, aid element extending through said sleeve bore, a spline formed at one end of one of the carrier and sleeve, an axially extending groove formed in an end of the other of the carrier and sleeve for receiving said spline to couple said carrier to said sleeve for rotary movement therewith and for axial movement relative thereto, a driver tube having an internal helical bead, said tube adapted to receive said carrier with said bead located in said track, means forming an annular groove in the outer surface of said sleeve, an inwardly directed flange on an end of said tube disposed in said groove, a resilient snap ring in said groove for positioning said flange against an edge of said groove, and an elongated casing adapted to be slid over said sleeve and into frictional engagement with said snap ring.

13. A writing instrument as in claim 12 including a nose secured to said sleeve for holding said casing in position on said assembly.

14. A writing instrument as in claim 12 including a cap frictionally supported by said tube for rotation therewith.

15. A writing instrument as in claim 12 including means for increasing the frictional force between said driver tube and said carrier.

16. A writing instrument as in claim 12 including means forming a second annular groove in the outer surface of said sleeve, said second groove being located between said first annular groove and the end of said sleeve adjacent said carrier and a spring clutch element disposed in said second annular groove for engaging the inner surface of said tube.

17. A writing instrument as in claim 16 in which said spring clutch is generally triangularly shaped element of resilient material.

18. A writing instrument as in claim 12 including means forming spaced slots in the wall of said driver tube adjacent the other end thereof, a bushing having internal ribs spaced correspondingly to said slots, said bushing adapted to be slipped over said other end to locate said ribs in said slots, external ribs on said bushing at locations corresponding to the locations of said internal ribs, and a cap frictionally received by said external ribs.

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