In September 2007, I presented a silenciously mysterious pictorial cancellation on a 1997 mail from Sweden (and reproduced here). Thank to a exhibited collection and my very thin knowledge of Swedish language, I can now talk a little more about it.
Kjell Ardvidsson published on line his collection about ten years of inkjet cancelling in Sweden on the inevitable philatelic exhibiting website Exponet.
And there, one of the picture talked to my memory. The illustration visibly served at the mail sorting facility in Karlstad, Värmland County, in Western Sweden.
Ardvidsson described it as the "Värmland symbol". However, my sole ressource is the Wikipedia in English's article about the region that develops the heraldic history. A wolve is mentioned that was replaced by the actual eagle.
I will continue to wait and look for what this symbol represents.
Kjell Ardvidsson has got his own website : http://kjell.smult.com/ , with, among other things, a specialised part about postage meter.