According to this, his real name was Tsukahara Jirō (塚原次郎), and he was born in Taisho 7 (1918), an army swordsmith. The sword on the site linked above was also made, or at least registered, in "Seki" (関).
Also, he took a 4th seat ranking (honorable mention) at the Military Sword Forging Technique Exhibition in 1944. 50 other smiths also ranked 4th. He is a known Seki smith from WW2.
Ohmura's site above also has an English information site with a lot of info on Japanese WW2 smiths and sword production. Well worth a look if you are into militaria.