US3288115A - Ball-point pen mechanism - Google Patents

Description

1966 E. HECHTLE BALL-POINT PEN MECHANISM Filed July 16, 1965 INVENTOR EM/L HECHTLE BY A? Main; ATTORNEY United States Patent Ofifice 3,288,115 Patented Nov. 29, 1966 3,288,115 BALL-POINT PEN MECHANISM Emil Hechtle, Oradell, N..l'., assignor to Radiant Pen Corp., Kenilworth, NJ. Filed July 16, 1965, Ser. No. 472,449 3 Claims. (Cl. 120-4203) This invention relates to a ball-point pen mechanism and more particularly to a pen mechanism for protracting and retracting the ink cartridge therein.

A pen mechanism that has been almost universally adopted employs a push button plunger that rotates a rachet which alternately engages and is disengaged trom spaced apart teeth on the inner wall of the pen. Such a mechanism is illustrated in Patent Number 3,120,837 dated February 11, 1964.

It has been found that in assembling the various parts of the mechanism that the teeth on the rachet sometimes jam into the plunger and interfere with the rachet operation.

Accordingly, it is an object of the invention to provide a ratchet and plunger mechanism that will fit more smoothly, that can be assembled without jamming, and which operates with less wear than the present types.

Another object is to provide a ratchet which will disengage easily from the plunger despite the pressure of the retracting spring, and thus facilitate the protract-retract operation of the cartridge.

These and other objects are accomplished and new results achieved as will be apparent from the pen described in the following specification, particularly pointed out in the claims, and illustrated in the accompanying drawing in which:

FIG. 1 is a front elevation of the assembled pen;

FIG. 2 is a longitudinally sectioned view of the same, taken in the plane 22 of FIG. 1 and in the direction of the arrows;

FIG. 3 is an exploded partly sectioned view of the pen parts;

FIG. 4 is a top plan view of the ratchet; and

FIG. 5 is a diagrammatic developed view of the cap teeth and slots.

The pen illustrated comprises a cap 10, and a barrel 12, a cartridge 14, a retract spring 16, and a protractretract mechanism 18 for operating the cartridge. The pen cap and barrel may be threaded as at 20 and 22 respectively for securing the parts in position. A band 24 is sometimes used to secure better alignment between the cap and barrel. The cap is preferably provided with a clip 26 which in the pen illustrated is secured to the cap by a hollow rivet 28.

The protract-retract mechanism 18 comprises in part, a plunger 30, terminating in an exposed push button 32 at one end, projecting through the opening 34 of the cap, and in a hub 36, made hollow as at 38, to receive the stem 39 of ratchet 40.

The plunger 30 is preferably formed with eight laterally extending guides 42, which are adapted to slide in slots 44 and 44a formed on the inner wall 46 of cap 10. The slots are positioned between rails 48 and 48a terminating in tapered teeth 50 and 50a respectively. The guides 42 of plunger 30 are always positioned in the slots 44 and 44a providing a longitudinal non-rotative movement of the plunger in cap. In the form illustrated, slots 48 are less deep than slots 48a although, as shown in Patent 3,120,837, the slots may be of equal depth.

The ratchet 40 is provided with a hub 52 from which laterally extends tour guides 54 each provided with a main tapered tooth 56 on the upper face thereof to engage the tapered teeth 50 and 50a of the rails 48 and 48a on the inner surface of the cap.

The lower edge of the plunger 30 terminates in eight teeth 58, which also engage the tapered teeth 56 on the tour guides 54 of ratchet 40.

The invention is characterized by providing the upper edge of the hub 52 with an auxiliary set of eight circularly arranged tapered teeth 60, for engaging the eight teeth 58 formed on the bottom edge of the hub 36 of plunger '30.

Thus when ratchet 40 is inserted into the bore 38 of plunger 30, the tapered teeth 58 of the plunger and the tapered teeth 60 of the ratchet will engage each other and align the parts as is shown in FIG. 2 preventing the sharp edges of tapered teeth 56 from cutting into the plunger and jamming the mechanism, preventing rotation of the ratchet.

A further advantage is that the plunger and ratchet teeth 58 and 60 respectively when engaged, will readily disengage to permit movement of the ratchet with respect to the cap and plunger without the need for an individual plunger spring to separate the parts as is shown in Patent No. 3,120,837 or for manual removal of the plunger from the -ratche-t.

The design of the teeth of the plunger, ratchet and cap, causes the ratchet to rotate slightly when released from the cap, and again when the ratchet teeth engage the cap. The ratchet teeth alternately move from the protracted position on teeth 5011 into the retracted position when the ratchet teeth engage cap teeth 50 and slide into slot 44a. From either position, the plunger when again pressed, will free the ratchet from the cap, allowing the ratchet to rotate slightly until the teeth lock, and then when deposited once more on the cap to rotate slightly again until caught in the protract position or the retract position, depending on the position of the ratchet guides with respect to the cap slots.

Thus the ratchet rotates slightly when depressed by the plunger, and again on the cap teeth when the plunger is withdrawn, causing a circular movement that permits the cartridge to be alternately protracted and retracted.

The spring 16 operating on cars '66 of the cartridge, forces the cartridge continuously against the ratchet in bore 62, the bevelled seat 64 being provided in the bottom of the ratchet for facility in inserting the end of the cartridge. The stem 39 of the ratchet helps to maintain alignment thereof throughout the protract-retract operation. The bevel of seat 64 is made possible by the extra hub diameter created .by teeth 60.

It will be seen that there is now provided a full uniform 360 contact between ratchet and the plunger teeth, except when the teeth engage on their tapered sides to initiate rotation. When the circular movement ceases, the 360 contact is resumed. The added contact between the auxiliary ratchet teeth and the plunger teeth also frees the plunger from the ratchet to permit movement of the ratchet on the cap teeth, without jamming with the plunger teeth.

I have thus described my invention, but I desire it understood that it is not confined to the particular form or use shown and described, the same being merely illustrative, and that the invention maybe carried out in other ways without departing from the spirit of my invention, and therefore I claim broadly the right to employ all equivalent instrumentalities coming within the scope of the appended claims, and by means of which objects of my invention are obtained and new results accomplished since the particular embodiment herein shown and described is only one of the many that can be employed to obtain these objects and accomplish these results.

What I claim is as follows:

1. A ball point pen having a cap, a barrel, a cartridge, a spring for urging the cartridge to -a retract position, and a protract-retract mechanism comprising a plunger terminating in a set of teeth, a ratchet upon which the cartridge 3 4 is seated having a set of main teeth, and a set of teeth on 3. The "ball point pen of claim 1 in which the main the inner surface of the cap for alternately engaging and ratchet teeth are one half the number of the auxiliary turning the main teeth of the ratchet to permit entry of ratchet teeth. the main ratchet teeth into the slots and for retaining the ratchetin retract position, said ratchet further provided 5 References Cit d b th E i w1th an nwardly posltloned set of auxlhary teeth for UNITED STATES PATENTS contact with the plunger teeth when the plunger engages the ratchet. 3,120,837 2/1964 Johnson 120-42.03 2. The ball point pen of claim 1, wherein the auxiliary 3,137,276 6/1964 Welsser set of ratchet teeth extends continuously and circularly 10 around the ratchet. LAWRENCE CHARLES, Primary Examiner.

Claims (1)

1. A BALL POINT PEN HAVING A CAP, A BARREL, A CARTRIDGE, A SPRING FOR URGING THE CARTRIDGE TO A RETRACT POSITION, AND A PROTRACT-RETRACT MECHANISM COMPRISING A PLUNGER TERMINATING IN A SET OF TEETH, A RATCHET UPON WHICH THE CARTRIDGE IS SEATED HAVING A SET OF MAIN TEETH, AND A SET OF TEETH ON THE INNER SURFACE OF THE CAP FOR ALTERNATELY ENGAGING AND TURNING THE MAIN TEETH OF THE RATCHET TO PERMIT ENTRY OF

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