How old is this Wakizashi

[partyjam3]

 I was wondering how old this Wakizashi is and if possible who the smith is? Google translate hasn’t helped me with the certificate. 

[Tsuku]

The certificate is a torokusho and it just says: wakizashi, length 44.2 cm, sori 1.1cm, 1 mekugi-ana.

 

The inscription column (銘文 meibun) says 判読不明 handoku fumei, meaning illegible.

[Shugyosha]

Finger in the air, I'd say the sugata is similar to Kanbun shinto (circa 1660) but it looks like the lines have lost some of their crispness so that might be off. I think shinto seems a reasonable guess though, rather than earlier or later.