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HARDWARE SET

Components needed (kit K1-BASIC): The hardware needed to complete this project can be bought as a PROJECT SET by clicking HERE…

OPERATION

QUICK FACTS

• Introduces essential concepts of circuit & switching theory
• Its modular design allows it to be integrated within any power-requiring project
• Uses a single 1.5v, AA battery but it can be expanded to be used with any size or number

HOW IT WORKS

The idea behind the Control Bar is to take advantage of a rotary action to connect a different voltage polarity to the motor it controls, when set to different positions. It consists of a rotor where the cables feeding the load are attached through screws (these being electrically conductive). The rotor is fixed to a pole inside the casing around which it is free to rotate. An inner ring provided with two aluminium sheet “C- shaped” strip is also fixed to the casing by means of two screws, one wiring its contacting strip to the positive terminal of the battery and the other to the negative. Each strip ends in two flaps that act as sprung-stops for the rotor screws, contacting when the rotor is given a CW motion. When this happens, the circuit is closed and the motor is fed with the battery voltage and power required to perform its duty! If the motion of the rotor is, however, in the opposite direction (CCW), the circuit is closed with the inverted voltage polarity, forcing the motor to then rotate in the opposite direction: full control! A cover or cap (04-CTLBAR) for the casing helps to protect the flapped terminals and prevent any of the parts from falling out of position.

The battery container is split into two parts: a holder and an axial spring. This makes it easier to 3D Print and assemble.  Both parts are also provided with aluminium strips that work as electric terminals. The axial spring fits into the holder by means of a “dovetail” sliding fit. Its function is to guarantee the battery contact with the terminals at all times. Also note that the casing attaches to the holder through a dovetail fit at the bottom in case you need casing and battery together.

Most of the effort to assemble this project comes in the fitting of the aluminium strips (refer always to the drawings for assembly). These are made out of kit component K1-AS and by carefully cutting with scissors the strips to size (see sheet 3 of the drawing for the dimensions for each strip). Once obtained, the strips need to be inserted into the slots at the inner ring, the holder and the axial spring using long nose pliers , then folding the strips as needed to obtain the desired shape.  Notice that the battery holder has a 3mm hole at the terminal end where a screw can be inserted. This is to create a small protrusion in the aluminium strip to improve contact with the battery.  Also, the axial spring has a hole for a screw to be inserted and used as a jack in case it becomes difficult to remove from the holder. DO EXERCISE EXTREME CAUTION WHEN CUTTING K1-AS. THIS MAY RESULT IN SHARP EDGES.

All that is left, is the action of wiring everything up. For this, you’ll need to use K1-WR, K1-WB (wires) and K1-TS (electrical terminal). If you don’t have a “Crimping Tool”, you can hammer-down the terminal’s plastic barrel to trap the cable edge within. If your dovetails don’t seem to fit due to material shrinkage (especially when using ABS) file down lightly any of the surfaces until you reach the right conditions for assembly.

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