Fountain Pen - Filling Mechanisms

Filling Mechanisms

The reservoirs of the earliest fountain pens were mostly filled by eyedropper. This was a cumbersome and potentially messy process, which led to the commercial development of alternative methods that quickly dominated the industry. However, newer, more convenient filling mechanisms have never entirely displaced "eyedropper-filling" pens in the marketplace, and they remain widely manufactured today. For some the simplicity of the mechanism, coupled with the large volume of ink it can encapsulate, compensates for the inconvenience of ink transfer.

After the eyedropper-filler era came the first generation of mass-produced self-fillers, almost all using a rubber sac to hold the ink. The sac was compressed and then released by various mechanisms to fill the pen.

The Conklin crescent filler, introduced c. 1901, was one of the first mass-produced self-filling pen designs. The crescent filling system employs an arch-shaped crescent attached to a rigid metal pressure bar, with the crescent portion protruding from the pen through a slot and the pressure bar inside the barrel. A second component, a C-shaped hard rubber ring, is located between the crescent and the barrel. Ordinarily, the ring blocks the crescent from pushing down. To fill the pen, one simply turns the ring around the barrel until the crescent matches up to the hole in the ring, allowing one to push down the crescent and squeeze the internal sac. Several other filling mechanisms were introduced to compete, such as the coin-filler (where a 'coin' or 'medallion' was supplied along with the pen) match-filler using a matchstick and a 'blow-filler' which unsurprisingly required the pen owner to blow into the barrel to depress the internal sac. In 1907 Walter A. Sheaffer patented the Lever filler, using a hinged lever set into the pen barrel which pressed down onto a bar which in turn compressed the rubber sac inside, creating a vacuum to force ink into the pen. Introduced in 1912, this innovation was rapidly imitated by the other major pen makers. Parker introduced the button filler, which had a button hidden beneath a blind cap on the end of the barrel; when pressed, it acted on a pressure bar inside to depress the ink sac.

Following the crescent filler came a series of systems of increasing complexity, reaching their apogee in the Sheaffer Snorkel, introduced in 1952. With the advent of the modern plastic ink cartridge in the early 1950s, though, most of these systems were phased out in favour of convenience (but reduced capacity).

Screw-mechanism piston-fillers were made as early as the 1820s, but the mechanism's modern popularity begins with the original Pelikan of 1929, based upon a Croatian patent. The basic idea is simple: turn a knob at the end of the pen, and a screw mechanism draws a piston up the barrel, sucking in ink. Thus they were easier to fill. This is also why this filling mechanism is very popular in today's fountain pens. Some of the earlier models had to dedicate as much as half of the pen length to the mechanism. The advent of telescoping pistons has improved this.

The Touchdown Filler was introduced by Sheaffer in 1949. It was advertised as an “Exclusive Pneumatic Down-stroke Filler.” To fill it, a knob at the end of the barrel is unscrewed and the attached plunger is drawn out to its full length. The nib is immersed in ink, the plunger is pushed in, compressing and then releasing the ink sac by means of air pressure. The nib is kept in the ink for approximately 10 seconds to allow the reservoir to fill. This mechanism is very closely modeled after a similar pneumatic filler introduced by Chilton over a decade earlier.

The Sheaffer "Snorkel" system filled the ink sac through a retractable tube above and behind the pen point. This eliminated the need to dunk the point in ink, and the subsequent need to wipe it.

A capillary filling system was introduced by Parker in the Parker 61 in 1956. There were no moving parts: the ink reservoir within the barrel was open at the upper end, but contained a tightly rolled length of slotted, flexible plastic. To fill, the barrel was unscrewed, the exposed open end of the reservoir was placed in ink and the interstices of the plastic sheet and slots initiated capillary action, drawing up and retaining the ink. The outside of the reservoir was coated with Teflon, a repellent compound that released excess ink as it was withdrawn. Ink was transferred through a further capillary tube to the nib. No method of flushing the device was offered, and because of problems from clogging with dried and hardened ink production was eventually stopped.

Around the year 2000 Pelikan introduced a filling system involving a valve in the blind end of the pen, which mates with a specially designed ink bottle. Thus docked, ink is then squeezed into the pen barrel (which, lacking any mechanism other than the valve itself, has nearly the capacity of an eyedropper-fill pen of the same size). This system had been implemented only in their "Level" line, which was discontinued in 2006.

Most pens use either a piston filler or a cartridge; many pens can use a converter, a device which has the same fitting as the pen's cartridge and has a filling mechanism and a reservoir attached to it. This enables a pen to either fill from cartridges, or from a bottle of ink. The most common type of converters are Piston-style, but many other varieties may be found in vintage Sheaffers.