What exactly were knee mortars?

Question

I came across a list of weapons used by the Japanese during World War II. One of the weapons that they used was the "knee mortar". I have been unable to find pictures of this weapon. As the title indicates, did the mortar have something to do the with the human knee?

Answer 1

There were actually Japanese mortars that fired off the knee. It was basically a big spring with a padded butt(kind of like the back of a rifle) and it you bounced it off your knee to shoot it into the air. No propellant. It was basically just a grenade that bounced. You can find them at military surplus stores sometimes. I cant find any pictures of it or anything..

The answers you have gotten so far refer to a mortar which was carried strapped to the leg and thus called "leg mortar", however, it was inappropriately translated into "knee mortar"
He that one is, pictures and all:
http://www.inert-ord.net/jap02h/knee/index.html

Answer 2

They answered that on the Military Channel once. They were small mortars that the Americans "assumed" were supposed to be placed against the knee to make them work, resulting in a lot of broken American knees!

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Watch reruns of "Mail Call" with R. Lee Ermey.

Answer 3

Not exactly designed to be fired from the Knee....it will bust you up. A small version of a mortar designed to be compact light for one soldier to use.

Answer 4

type 89 grenade discharger 50 mm

the name came from a mistranslation of the japanese word