What is Pelikan's 'thermic-regulator' and how does it work?

[HartGummi]

From a descripton of Pelikan P1:

Quote

In September 1958 Pelikan introduced the first of a new generation of fountain pens that had been completely redeveloped in construction and design. The shape was slimmer than previous fountain pens. The piston mechanism had remained unchanged technically. But the key was the new ink feed. Developed by Theodor Kovacs and called the 'Pelikan thermic-regulator', it had a significantly larger volume for storing remaining ink. Atmospheric pressure and temperature variations were no longer a problem. In addition, this new development now also allowed the installation of a hooded nib.

From https://www.pelikan-collectibles.com/en/Pelikan/Models/Revised-Piston-Fillers/P1-Other/index.html

 

Can anyone explain how this feed resisted pressure and temperature variations?

[stoen]

Hello, 

I’ll try to give a short answer without becoming overly tehnical. I haven’t serviced any of those pens so I can only go through the Kovacs draft.

 

Atmospheric conditions (height, temperature, humidity, air travel, condensation dynamics...) are known to cause variations in air pressure which can impair pen performance and cause other inconvenience.

 

These cross-sections in the Kovacs draft look like design of an elaborate system of interconnected channels, vents, chambers and membranes engineered to equalize the air pressure inside the barrel with the outside air pressure in a way it wouldn’t affect the optimum ink flow. This also appears to have included narrowing or widening of the ink channel until the pressures equalize (element 23 in Fig.1. and Fig.4.). Looks like the elements 22 and 35 were termically sensitive and controlled the air intake. Looks like the labyrinth of interconnected ink flow compensation chambers allowed for larger “reservre” ink storage. If you want to go into details, please take your time to analyze the draft yourself. Please pardon my not going into more details: translating intricate machine engineering drafts into words goes somewhat beyond the scope of this forum.

 

It also looks like the hooded nib could be installed because the section was designed so that the air pressure changes couldn’t cause the ink overflow/underflow in the parts below (left of) the cross-section IV-IV in Fig. 1., where the nib gets plugged in.

 

Hope this can help. I’m sure that someone with hands-on servicing experience with these particular pens could help more.

[Bo Bo Olson]

I didn't know this about my later Silvexa. I just knew it was a semi-nail, not that it had brand new guts in it. Whoops just looked.....Mine is a cartridge pen, not a piston pen....but it's got a nib I won't use either way.

 

When I could have gotten post '65 to '82 P or M type Pelikans cheap, no one could answer if the nibs were semi-flex or regular flex; in none had any....so I stayed away from them...thankfully.