New unknown item

[Larrythepilot]

Our museum has an item that we don't even know what to call it to talk about it. We have tried to get it ID'd before, but no luck. It may have already been on this forum in the past, but I don't know that. I took fresh pictures of it earlier today, but we also have pictures on file from June of 2020. This "thing" is fairly sophisticated. As I took the pictures today, I made observations and notes. Here's what I have.

From the way writing appears on the item, it appears that the proper orientation is with the large black knurled knob down. In that position, it measures about 15 inches from the end of one arm to the end of the other arm. The height is 9 inches, and the width 7 inches. There is a non-linear scale on the upper side of the knurled black knob, from 0 to 1000. The spacing is much farther apart as you approach the 1000 end. On the end of one of the arms is a tapered mounting socket, indicating that maybe it was taken down when not in use.

There are numbers stamped into the aluminum castings. They include 76, 17 170, and 17 158. Wherever there is a number stamped, it is accompanied by symbol shaped kind of like a diamond laying on its side. I photographed the numbers; you can see them quite clearly.

There is a ball on a post that slides in a channel. Looks like that if you turn the knurled knob at the bottom, the ball would slide, causing part of the mechanism to tilt. It's as if the device is some sort of aiming system, and maybe the 0 to1000 scale is range in yards or meters. Down inside the mechanism, on each side of the shaft that supports the ball, there is a copper pad on each side. One side has scale which would indicate how far the ball moved, and the other side has an arrow, and what looks like Japanese writing - ???

My final comment is that the whole thing looks like it was once taken apart (for evaluation - ??), and then hastily reassembled. Some screws are missing, and others don't appear to be seated all the way. The cotter pins are missing from the the castellated nuts.

I'll post the pictures now. Since I have the item here at home, if any of you have a question, or want a picture from a different angle, I can do that easily and promptly. I hope one of you can figure it out. This thing

has been a mystery to too long.

 

[special ed]

I don't know what it is, but it sure is a nice one.

 

[Snautzer01]

Looks a bit like: your thought Shinpachi

 

[Antarctica]

To me, the "100 X" & other numbers would indicate either a navigation or gun-sight / bomb-sight item.

 

[Larrythepilot]

Thank you, Antartica. I agree. I have long thought that it has to do with range an inclination. Most of the items that we have here at the Freeman Army Airfield Museum are aircraft/aviation related. That's because we were the Foreign Aircraft Evaluation Center right after WWII. But this one is maybe an interloper. It looks like it was used on a ship, or on some ground-based gun. Most museums acquire an item when somebody brings it in an offers it as a donation. The donor knows what it is, and maybe detailed history of where it came from. Not us. Our items were buried and forgotten about after WWII. 50 years or more later, we're digging them up. There in no ID or origin. It's not that we are so dense; it's that on many items, we have no place to start from. Thanks for your interest.

 

[Shinpachi]

This says "飛行方向 (Flight direction)"

 

[Larrythepilot]

Aha! We have been wanting to know what that said. Thank you, Shinpachi. ..... Since it says flight direction, that means it really is aircraft-related; not ground- or water-based as I suggested yesterday. There is hope to identify this thing yet.

 

[Shinpachi]

This can be read "100x粁/時 (100x kilometers/hour)"

Other clue will be this trade mark "五階菱+工 (5 diamonds + decorated ko)". Ko for kogyo (industry).

 

[RichardSuhkoi]

So a bomb sight?
The Planes of Fame museum have several aircraft with bomb sights on them.

 

[Larrythepilot]

I have been away from this identification project for a while, working on other things, like my complicated (for me) income taxes.

Thank you, Shinpachi, for translating the Japanese writing and symbols on this item. ..... And thank you Richard Suhkoi for suggesting that the Planes of Fame museum might have an aircraft with such a device installed. I was at PoF for half a day once, about 20 years ago. I don't remember much, except they had a Bf-108 that was at one time here at Freeman Army Airfield. It was in storage (not on public display), and I had to twist their arm pretty hard to get to look at it. I was also interested in their P-26 "Peashooter", to get some detailed information about the tailwheel assembly for a friend who was building a replica. They were gracious and let me go inside the ropes and crawl around on the floor to take close-up pictures. I think I'll call PoF this week and ask if I send photos, would they look at their aircraft to see if one has our unknown device.