US3459485A - Fountain-pen closing device by means of a cap - Google Patents

Description

Aug. 5, 1969 G. F. RIGONDAUD 3,459,485

FOUNTAIN-PEN CLOSING DEVICE BY MEANS OF A CAP Filed Jan. 19, 1967 United States Patent M Int. Cl. p431; 9/00 U.S. Cl. 401-246 3 Claims ABSTRACT OF THE DISCLOSURE A writing instrument in which a resilient cap can be removably secured on a body to cover a tapered front section of the body at which the writing nib is located. At the rear part of the tapered section is a cylindrical groove which is adjoined by cylindrical surfaces forming radial shoulders at the ends of the groove. The cylindrical surface furthest from the tip has a greater diameter than that of the other cylindrical surface, and the cap has a plurality of internal part-spherical projections defining a cylindrical interior opening which is smaller than the diameter of the smaller cylindrical surface whereby when the body is inserted into the cap, the latter is resiliently deformed, and when the projections reach the groove they are urged thereinto by the elastic action of the cap, the degree of penetration of the body into the cap being limited by the contact of the lower edge of the cap with the shoulder at the larger cylindrical surface.

The present invention relates to a closing device for fountain-pen by means of a cap.

A number of closing devices for fountain-pens by means of a cap are known, the oldest of which is no doubt the one resorting to a cap adapted to be screwed on the fountain-pen body, to achieve the desired closing thereof.

To avoid the cumbersome rotational action along several turns of the cap, for closing and opening the same, devices were proposed, whereby the closing and opening are obtained by a simple longitudinal relative translation movement betewen the cap and the fountain-pen. In spite of the numerous devices of such type, none have given complete satisfaction up to the present.

Some of these devices achieve the connection between the cap and the fountain-pen by simple friction: the closure position of the cap is not satisfactorily assured, and neither is the tightness.

Other known systems utilize, sometimes with friction, a snap connection adapted to ensure the closure position. In all these known devices, however, the user, after having pushed the cap over the body of the fountain-pen to the closing operation, meets a resistance at the end of the movement, so that, frequently, be interrupts the same too ea'srly, believing that he has effectively closed the fountainpen, although this is in fact not the case: not only will the cap then tend to separate from the body of the fountain-pen, but the tightness of the inner cap compartment is not achieved, and the ink will eventually evaporate.

Most of the known devices are, moreover, of a rather complex construction.

It is an object of the invention to provied a cap closure device for a fountain-pen which avoids the disadvantages of the previously known devices.

The invention has more particularly for its object to provide a device whereby a user will find it practically impossible not to reach the effective closure position, thus establishing for the cap memberat any timeits required tightness.

It is another object of the invention to provide a de- 3,459,485 Patented Aug. 5, 1969 vice which will readily and easily operate, both for opening and for closing the cap member.

It is also an object of the invention to provide a device of a simple constitution and, consequently, of a low cost price.

It is a further object of the invention to provide a device which in no manner interferes the aesthetic appearance of the fountain-pen, while on the contrary, it improves the same.

The invention will be best understood from the following description and appended drawing, wherein:

FIGURE 1 is a view with parts broken away of a portion of the fountain-pen fitted with the closing device according to the invention.

FIGURE 2 is a longitudinal cross-sectional view of a portion of the cap member according to the invention, adjacent the orifice thereof.

FIGURE 3 is a view of a fountain-pen body at its portion adapted to cooperate with the cap member.

FIGURE 4 is a cross-sectional view of the fountainpen cap taken along line 44 of FIGURE 2.

FIGURE 5 is a longitudinal cross-sectional view of part of the cap member cooperating with the fountain-pen body, in a position slightly preceding the closure.

FIGURE 6 is a view similar to that of FIGURE 5, but in a position directly preceding the closure.

FIGURE 7 is a view similar to that in FIGURES 5 and 6, corresponding to the closed position.

The section 10 of the fountain-pen (FIGURE 1) comprises at the rear end thereof a cylindrical outer surface 11 (FIGURE 3) leading at its back end portion into a groove 12 of a rectangular profile. The groove is formed with a cylindrical bottom 13, a front shoulder 14 and a back shoulder 15. The front shoulder forms part of section 10. Advantageously, the back shoulder 15 constitutes the front section of the tubular body 16 of the fountainpen, connected to section 10 by a threaded engagement.

Metal cap 20 (FIGURE 2) is substantially cylindrical in portion 21 adjacent its orifice 22. Close to said orifice, there are provided along a transversal section perpendicular to the longitudinal axis of the cap member, three inner, uniformly distributed projections 23 23 23 (FIG- URE 4. These projections may be obtained by driving balls into the outer portion of the cap member, thus assuming the shape of portions of a sphere. The apexes 24 24 24 of said spherical portions are located along a circle the diameter of which is very slightly smaller than that of the outer cylindrical surface 11 of the section.

Inside cap member 20, there is provided a lining or packing, which may be of plastic material, for instance polyethylene. This lining is in the form of a tube open at one end, which comprises a cylindrical body 31 extending towards the bottom of the cap member through a truncated-conical portion 32 connecting to a plane bottom 33. On the side facing said frusto-conical portion 32, body 31 has a thickened part 34, forming an outer cylindrical bearing v35 and beyond part 34, body 31 continuing as a thinned cylindrical portion or lip 36, the edge 37 of which limits the orifice of the lining. The inner surface 38 of the lining is cylindrical from edge 37 up to the truncated-conical portion 32. Body 30 is secured in the metal cap member 20, for instance by simply pushing it into the latter.

The device operates as follows:

When inserting the cap member 20 over section 10, and as soon as the projections 23 reach the cylindrical surface 11 thereof, which is merely a continuation of the tapered front portion 40: of the section, a certain resistancealthough slightwill be produced to the advancing motion.

Upon continuation of this insertion movement of the cap this slight resistance is overcome and the smooth friction action due to the nature of the material constituting the section and the surface thereof, no difficulty will arise to oppose the advancement of the cap. During the whole insertion, the cap member is under a uniform, reduced stress, the action of the cylindrical surface 11 on projections 23 deforming it very slightly, on account of its resiliency. Lip 36 facing the tapered portion 40 of the section has no contact with the latter.

When approaching the end of the advancing movement, the apexes 24 are clear of the cylindrical surface 11 on account of the groove 12, and the resilient reaction of the cap member exerted on an inclined surface part 25 of the projections 23 gives rise to a forward motion of the cap (the latter being unable to remain in an intermediate position), to cause the cap to assume the complete closing position, i.e. the position for which edge 26 of the cap abuts against shoulder 15. In this position, lip 36, thin and resilient, contacts with the tapered portion 40 of the section, whereby the lip is slightly expanded, thus assuring perfect tightness of the enclosed space inside the cap member. This junction enables a certain tolerance along the axial direction. In the closed position, the outer edge 27 of the shoulder 14 cooperates with edge 28 of the spherical projections 23, and thus ensures said closed position. Consequently, and in contradistinction to previously known devices, the closure is not preceded by the occurrence of a resistance to penetration, but on the contrary, in the immediate neighborhood of the closure position, this resistance to insertion disappears, leaving the stresses created in the cap member to develop resilient forces adapted to unavoidably bring the cap member in its closure position, for which the tightness of the chamber inside the cap member is assured.

To open the fountain-pen, it is necessary to exert a substantial effort to displace cap member from body 16, and enable the projection 23 to pass the edge 27, whereafter a smooth gliding motion is achieved without difficulty, the guiding being provided by the cooperation of the three projections 23 with the cylindrical surface 11. It is also to be noted that the closure device applies not only to the fountain-pens proper, but also to any kind of writing instruments.

What is claimed is:

l. A closing device for a writing instrument comprising a body, and a resilient cap which is removably securable on said body, said body including a tapered front section with a rear part having a first cylindrical surface,

a cylindrical groove and a second cylindrical surface arranged in that order in the direction of increasing size of the tapered front section, said cylindrical surfaces adjoining said groove to form shoulders which laterally bound said groove, said second cylindrical surface having a greater diameter than that of said first surface, said cap having a lower edge with an opening thereat for receiving said tapered front section and including a plurality of internal part-spherical projections defining a cylindrical interior opening which is smaller than the diameter of said first cylindrical surface whereby when the body is inserted into the cap, the latter is resiliently deformed, said projections being spaced from said edge of the cap such that with the body inserted into the cap said projections can engage in said groove while said lower edge of the cap contacts the shoulder formed by said second cylindrical surface which thereby forms an abutment for said cap, said projections having an axial length of such dimension that with said lower edge of the cap in contact with said corresponding shoulder the projection contacts the other shoulder, the spherical projections each having a radius such that when a portion thereof furthest remote from said edge of the cap reaches the shoulder formed by said first surface, the projections are urged into said groove under the elastic action of said cap.

2. A device as claimed in claim 1 wherein said cap comprises a metallic element and a resilient lining in said element which sealingly engages said body at the surface of the tapered section in the position in which the cap is secured on said body.

3. A device as claimed in claim 2 wherein said lining comprises a thin resilient lip facing said tapered section of said body to form a seal therewith upon contact of the lip and said body.

References Cited UNITED STATES PATENTS 3,171,196 3/1965 Helitas 401-244 X 1,583,579 5/1926 DeWitt 401-246 2,274,470 2/ 1942 Boyle et al 401-246 FOREIGN PATENTS 22,077 9/1910 Great Britain. 119,269 7/ 1947 Sweden.

LAWRENCE CHARLES, Primary Examiner

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