The Addimult Ziffrex adding machine

This is the Addimult Ziffrex. It’s quite a large, bulky adding machine, but it’s fairly simple. Functionally it is very simillar to the Addi 7, or the Triumphator Klein-Addiermaschine, but internally the mechanism is more similar to the Resulta. Both of those are much smaller machines than this one. So this one was made by Addimult. It was made in around 1957. It has a serial number at the bottom, 10275, but that doesn’t mean that there were 10000 of these made. I think only about 2000 probably. And it says “Made in Western Germany”. The factory were this was made was in Bad Harzburg, which is close to the border with East Germany.

01:14 - And I thiink it was only made in around 1956 till 1958, not much longer than that. The way it works is fairly simple. It has these levers, and if you pull on them the number you’ve set becomes visible in this input display register at the bottom. It has seven digits for the seven levers. And as you set the levers the number also immediately gets added to the main register, which is an eight digit register right here. Once you’ve added a number you can press this big button on the front, and that releases the levers and so then you can add another number. As you can see the main register carries as you would expect.

02:28 - These levers, they lock in position but if you’ve moved it too far you can move it backwards but then you have to push it down. You have to push the button down and then you can move it back a few steps. To clear the main register you have this clearing knob on the side. You have to turn that one full rotation until it clicks. You can also subtract, and that’s what this lever is for. This changes the mode of operation from addition to subtraction. And unfortunately you now no longer can read the the main register. Internally then the mechanism moves about so that now when you pull the levers the numbers you’ve entered get subtracted from the main register but you can’t really see it. You can only see it when you put it back onto addition and then you see the result here. The way it works is that normally the main register is driven through intermediate wheels, wheels in between the toothed segments of these input levers.

04:22 - And yeah, when you switch to subtraction, the register moves up against the input lever toothed segments and the intermediate wheels move out of the way so then they’re driven directly and they move in the opposite direction as before. And yes, that’s pretty much all there is to say about the Addimult Ziffrex. Only thing really I know is that Addimult used to make slide adders, and this kind of machine seems to be not really in their normal style as it were. And it’s not really known who designed this. I haven’t been able to find any patents for it, and it is actually quite possible that it was made in a factory of some third party and that Addimult had the exclusive rights to sell it under their brand name. So that was the Addimult Ziffrex. Thank you for watching! .