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The Signature Junior Adding and Multiplying Machine

The Signature Junior Adding Machine

The Signature Junior Adding and Multiplying Machine
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The Signature Junior Adding and Multiplying Machine

The Signature Junior is a toy adding machine sold by Montgomery Ward in the late 1960s. The machine mostly is made of thin metal plate, similar to the Add-em or Peter Pan, though its upper casing is made of orange plastic. It was invented by Shigeaki Kuramochi and made in Japan by Soken. Montgomery Ward used the Signature Junior brand for the top of the range toys, which also included a sewing machine, a typewriter, and a record player.

This adding machine looks like a minature cash register. It has a 5-digit register at the top, which can be reset by turning the crank on the right hand side anti-clockwise. The curved keyboard has four full columns of keys, numbered top to bottom from 0 to 9, with a totals button to the right. After entering a number on the keyboard including leading zeroes, you press the totals button to activate the electric motor which adds the number to the register. The electric motor is powered by two size D torch batteries. On the right is a fold-out memo table, which has a hole for storing the pencil that came with the machine.

The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine

My machine comes with its original box.

The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine

It came with a single page instruction sheet, plus a small slip of paper with extra instructions for doing multiplications. There should also be a sticker on the memo-table with a brief version of the instructions, but this is not present on mine.

The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine

The mechanism is relatively simple, and reminiscent of what is used in the first Burroughs adding machines. Pressing the Total button causes two things to happen. The axle holding the gears that drive the number wheels is lifted away from the number wheels, disconnecting them, and the electric motor is triggered. The motor drives a wheel that pushes a set of spring-loaded arms back and forth along the underside of the keyboard. Any depressed key will block an arm from moving further. Just as the arms start their return journey, the gears are reconnected, so that the number wheels are moved an amount proportional to the distance that the arms travelled on their return, namely the number entered on the keyboard. The carry mechanism consists of a set of switches. The moving arms normally rest against those switches when they return, but when a number wheel passes 9 it triggers the next switch, rotating it away from the arm, and this allows the arm to move back a little bit further than normal, which adds an extra 1 to its digit. The carry switches are reset the next time the Totals button is pressed.

The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine
The Signature Junior Adding Machine

The instruction sheet says:

INSTRUCTIONS

HOW TO OPERATE B/O ADDING & MULTIPLYING MACHINE


PREPARATIONS:

  1. Insert two "D" Batteries in line in the battery case at the bottom of Machine (Direction of batteries is indicated in the battery case)
  2. Before operating this machine, be sure that the figure on the Scoreboard indicates "0" on each column. If not, rotate Side Handle counter-clockwise until "0" is shown on all columns. Also, make sure that the handle is straight down position.

ADDINGS:

  1. To register a basic figure on the Scoreboard, push down any numeral buttons, one each from 4 columns on Keyboard (0001 to 9999). Then depress "TOTAL" button. Figure or the number you desired will be reg- istered on the Scoreboard.
  2. Now, push down another figure which you wish to add to the original figures or the number already scored on the board. Then, push down "TOTAL" button again. The total figure of two numbers will be registered on the Scoreboard.

MULTIPLYINGS:

  1. After setting machine for operation (Paragraph 2 of Preparations), register any numbers you wish on the Scoreboard. (Paragraph 1 of Addings). Then, keep on pushing "TOTAL" button repeatedly. When you push "TOTAL" button once, you Will get the "Double" of the original figure on the Scoreboard. And against the second push on "TOTAL" button you will get "Three Times" of the original figure and so forth. (Example: If the original figure is 2222, 4444 will be scored against first push on "TOTAL" button, and 6666 against second push, 8888 against third push, 11110 against fourth push etc.)

RESETTING OF MACHINE:

To clear the figure on Scoreboard or to reset the machine for next operation:
  1. Rotate the side handle counter-clockwise till you get "00000" on the Scoreboard and set the handle at vertically down position.
  2. Push down "0" button on each column on the Keyboard to clean off figures on the Keyboard. "TOTAL" button will be locked automatically then.

CAUTIONS:

  1. When number of 5th column on Scoreboard exceeds 9, or the answer exceeds 99,999, "0" will appear on the 5th column. (Example: When you add 2,850 to 98,256, indication on the Scoreboard will be 01106)
  2. When you register or add a number less than 1,000, do not forget to push down "0" on column representing Thousands, if desired number or the number to be added is less than 100, push down "0" s represesenting Thousands and Hundreds. If desired number is less than 10, push down "0" on the column representing Tens too.
  3. When you push down more than one button on any given columns on the "Keyboard", lesser pushed number of that column will be scored.
  4. If the machine stops during operation after numeral buttons were pushed down, take out batteries. Then push down "0" on each column of Keyboard. After cleaning off the figure on Keyboard, insert batteries again. Motor will run for a few seconds and stop. The machine is ready for next operation then.
HANDLE must ALWAYS be at straight down position, before starting operation!

PRINTED IN JAPAN

It is not clear why the instruction sheet calls it the B/O Adding and Multiplying Machine. It has been sold under the name Brainy-Mate, but it is possible that it was given other names too, especially if it was also exported to countries other than the United States.

GUIDE TO MULTIPLYING OPERATION

285×34
  235
×  34
 1140
 855 
 9690
 First, push down 0285 on Numeral Button Panel and press "TOTAL" Button four times consecutively. (1140 will appear on the SCOREBOARD). Leaving this figure on the SCOREBOARD, push down 2350 and press "TOTAL" Button three times. The correct answer 9690 will appear on the SCOREBOARD then.

Following the pattern shown above, you can carry out any multiplying indicated as follows.

Any single number   (1-9) × (1 to 9999)
Any two column number   (10-99) × (1 to 999)

Exercise:

  76×24= (0076×4) + (0760×2) =   1824
487×36= (0487×3) + (4870×3) = 17532
999×99= (0999×9) + (9990×9) = 98901

Note: Always multiply larger number by smaller number.

Printed in Japan


Video

Here is a video where I demonstrate the Signature Junior Adding Machine.



Advertisements and articles

The only advertisements that I have found for this machine are from the 1966 to 1968 Montgomery Ward Christmas catalogues. The price was just under $10.

1966 Montgomery Ward Christmas Book
1967 Montgomery Ward Christmas Book
1968 Montgomery Ward Christmas Book

Patents

PatentFiling datePublish dateNameDescription
US 3,300,13006-12-196524-01-1967Shigeaki KuramochiToy Adding Machine


Links

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