ID a Japanese Tachometer as to Usage... Tank, Sub, etc.??

[MikeS0000]

Hello Folks -

My small collection of WW2 Japanese Gauges. I just added the tachometer on the left. It is compared to the Dive Bomber flap gauge on the right for scale.

I don't believe the tach is a standard truck or vehicle gauge, due to its construction. It weighs in at ~2.5 lbs. which is really hefty. There is an aluminum ring holding the glass face and steel case in the back. Each is made of 3/16" thick aluminum and steel. Real overkill for a truck or car.

There appears to be an Army Star preceding the serial number. I checked out some of the engine data used in the tanks and it seems to match what the scale markings are on the dial.

Interested in figuring out what it may have come out of and appreciate any thoughts.

Thanks and Best Regards!
- Mike

[Nick Komiya]

Typical example of data plate having left to right writing. The name of the company is its pre-1943 name and the inertia type tacho must have been a licensed production of a Stewart Warner design they started to make in 1937

[MikeS0000]

Thanks Nick! Does the outer measurement indicate pressure? Interesting in that it is probably one of the more minor designs that had the tables turned on the inventors.

[Nick Komiya]

Both rings are revs/min, the outer being for the engine and inner one for the pump