The creation of new filling systems has always been, especially in the golden age of the development of the fountain pen, one of the major factors of technical innovation, and for this reason also the birth of new companies; In this field the most famous examples are the Conklin, born for the invention of the Crescent filler and the Sheaffer, which entered the market with the creation of the lever filler, but many other less known companies (such as the Onoto, the Dunn, the Moore or the Chilton) have had a similar origin.
The history of the fountain pen is in fact inextricably linked to that of the various systems that over the years have been designed to fill the ink. In particular, in the early 1900s all manufacturers competed to introduce new filling systems, often unnecessarily complicated and not very functional, which were then used to promote the superiority of their pens.
Below are the main loading systems used by the various manufacturers throughout the long history of the fountain pen from its origins to the present day. The various systems have been grouped by affinity of operation, and the various groups are presented in an approximate chronological order of introduction.
- 1 Direct filling
- 2 Direct compression of the sac
- 3 Lever fillers
- 4 Sac mechanical compression fillers
- 5 Pneumatic fillers
- 6 Breather tube fillers
- 7 Vacuum fillers
- 8 Others
- 9 External references
- 10 Notes
- 11 Thanks
This first grouping includes all those filling systems that require the pen to be loaded by directly inserting the ink into the barrel. These are the most primitive loading systems, used at the beginning of the fountain pen history. In most cases they have been replaced since the beginning of the 1900s by systems that allow automatic filling.
In the systems illustrated in this section, the body of the pen also acts as a tank, and there is no mechanism to automate the loading of the ink, which is usually entered by an eyedropper; the variants proposed relate only to the different methods used to give access to the tank.
The eyedropper filler, also called drop filler is the first filling system used in fountain pens and in reality it cannot be considered even a real filling system, since in essence there is no "system".
In this case, in fact, the pen is filled by removing the nib assembly from the barrel, which is used directly as a tank. The refill operation is carried out, once the access to the tank has been obtained, with the introduction of ink to be carried out usually with a dropper, which in the original versions was supplied by the manufacturer together with the pen. Once the refill was completed, the nib assembly had to be reassembled on the barrel in order to use the pen.
Because of its simple construction, this "system" was adopted by all manufacturers from the 19th century to the dawn of the development of the fountain pen, and remained in use until the beginning of the 20th century. The system is simple, especially in terms of technical requirements for construction, and also has the advantage of allowing a large capacity of ink, greater than any other, as determined only by the size of the pen body.
However, it has many drawbacks, the first of which is undoubtedly the inconvenience of filling operations, since to refill a pen you have to disassemble the section with the nib, usually wet with ink, and store it in a separate place where it does not stain and does not risk falling. The refill operations are very uncomfortable, it is necessary to have a dropper or similar tool, and in general the operation of the transfer of ink, having to keep always well vertical the body of the pen that acts as a reservoir, is delicate and at risk of stains and spills of ink.
A second drawback arises from the fact that with wear, especially in lower quality models, having the ink in direct contact with the body of the pen can cause leaks at the junction between the barrel and nib group once it loses the seal. Moreover, having to unscrew and screw the latter, the risk of staining the hands, especially in the presence of a body that has been full of ink until then, is always quite high. The body of the pen then had to be made only of inert material that was able to resist contact with the corrosive agents present in the inks, which at the time of its introduction was only the hard rubber.
A last drawback, often very annoying, is that since in this case the ink contained directly in the body of the pen, when it is emptied, there is a considerable sensitivity to changes in pressure and temperature of the air contained within the pen barrel, which is the greater the greater the volume available. The biggest problems were then in the case of air travel, where variations in altimetric pressure invariably caused a leakage of ink.
But with these pens to cause a leak is often sufficient only the heat of the hand that holds the pen. This is transmitted to the air contained inside the barrel, causing an expansion that alters the balance of pressure between inside and outside. This makes it relatively easy to obtain a loss of ink. Although today it is back in fashion in some models, for its retro taste, it remains, however, provided that it can really be considered as such, a primitive filling system.
This "system" is found exclusively on Japanese pens, and can be considered a variant of the plunger filler of the Onoto, from which it was probably inspired. On a mechanical level, in fact, the mechanism is essentially identical, but in this case it is not used to fill the pen, but only to block the flow of ink to the nib when the pen is closed. It is not known an inventor of this mechanism, that it is found on around all Japanese pens produced until the years '30 from companies like the Pilot and the Sailor.
The pen is filled by unscrewing the nib group and inserting the ink directly into the body of the pen, as for the ordinary eyedropper filler. However, to avoid possible losses, which would be disastrous for the traditional clothing of the Japanese (the kimono), the pens equipped with this system are equipped with a piston mounted on a shaft operated through the bottom of the pen. When the bottom is screwed on, the piston, which serves exclusively as a blocking valve, comes into contact with the nib group, blocking the access of the ink to the same, so as to prevent any possible leakage.
In order to write it is necessary to unscrew the bottom and slightly withdraw the shaft attached to it, so as to retract the piston from its blocked position and re-enable the flow of ink towards the nib. Closing the bottom will stop the ink flow again, thus preventing leaks.
Direct compression of the sac
At the beginning of the 1900's, there was a great impulse in the search for a system that would allow the filling operation to be carried out automatically. During this period, a series of filling systems began to be produced, in which the ink was kept inside an elastic rubber sac. In this way it was possible to carry out the loading by compressing the empty sac, so as to exploit the subsequent expansion of the same to suck the ink from the bottle by immersing the nib assembly.
The idea of using a rubber sac as an ink tank helped to solve some of the problems encountered until then. In particular, since the ink was no longer in contact with the material of the pen barrel, it was also possible to use materials that were susceptible to corrosion. Moreover, if the rubber tank is well positioned and is not placed in contact with the walls of the drum, the layer of air that separates it from it acts as thermal insulation, and the elasticity of the bag compensates for the problem of increased pressure due to the heat transmitted by the hand that holds the pen.
However, there are also drawbacks: first of all, the size of the tank decreases, since the space inside the barrel of the pen must contain it, along with all that is necessary for the compression system. Moreover, the sacs tend to deteriorate, breaking or losing their elasticity, and must be replaced, thus introducing a whole series of maintenance problems. Finally, the complexity of the construction increases considerably, and with it the possibility of failure.
In this second section we have collected all the simplest and most primitive filling systems that provide some form of mechanical compression action performed directly on the rubber sac, or better, on the so-called pressure bar a metal bar that is placed (or glued) on the sac to allow you to apply the compression to it in a uniform manner.
Below are the main loading systems used by the various manufacturers throughout the long history of the fountain pen from its origins to the present day. Many of these systems were born as an attempt to circumvent the original patent of Sheaffer, or to find alternatives that could distinguish the pens that used them compared to the competitors.
The principle of these loading systems always remains that of compression, and subsequent expansion to suck the ink from the bottle, of a rubber sac; therefore, the general considerations on advantages and disadvantages made in the previous paragraph apply. The substantial difference is in the mechanism with which the compression is carried out, however also in this case it is generally made use of a rigid pressure bar, pressed by the mechanism of the lever, to distribute uniformly the pressure on the sac.
Sac mechanical compression fillers
This section brings together all the other loading systems based on the mechanical compression of a rubber sac, but carried out by means of a mechanical system that does not refer directly to the lever principle, and therefore used as a legally conclusive alternative to the system introduced by Sheaffer.
This section classifies loading systems based on the pneumatic compression of a flexible rubber sac. The latter is compressed by the atmospheric pressure generated by the filling system to release the air that will be replaced by the ink during the decompression phase, when the sac returns to its normal size due to its elasticity.
Breather tube fillers
These filling systems have in common the use of the presence of a breather tube which allows to perform the refill by repeating several times some mechanical action (different depending on the different filling systems) which allows to create a compression of the air inside the pen tank. The variety of ways in which this compression is carried out has been extremely wide, but in most cases provides some mechanism that acts on a flexible bulb.
The breather tube is inserted in the feeder and kept in a central position with respect to the body of the pen, which normally acts as a tank. During the compression phase, the air in the pen comes out of the blowhole, from which, due to the depression created, the ink that ends up in the tank is loaded; the presence of the blowhole means that the ink loaded is not expelled in the subsequent compression phases, until the entire tank is filled up to the level of the blowhole.
The presence of the breather tube in some realizations also has a second positive effect because it allows to immediately balance the pressure of the air inside the pen body with that of the external air, since in this case the breather provides a way of communication between inside and outside, thus avoiding the various problems of leakage of the ink in case of pressure changes.
This group brings together all those systems that require that the filling takes place through the creation of a depression inside the body of the pen so that the ink is sucked through it. In this case it is generally the body of the pen itself that acts as a reservoir, and can be made of transparent material so as to allow the visualization of the ink level.
As with other systems that use the pen body as a reservoir, this also has the advantage of having a greater volume to contain the ink, but the disadvantage is that the residual air contained in the reservoir is sensitive to changes in temperature, which makes it easier, due to the increase in volume in case of heating, the cases of leakage of ink, especially when the pen is almost discharged and the volume of air is greater.
All the other filling systems have been brought together in the latter group, which have in common the fact that they do not have a common factor that allows them to be classified in a homogeneous manner.
A big thanks to Fabio Moricci, the Pennaio, who kindly gave us the use of his sketches as a basis for the realization of the technical diagrams of the various loading systems.