How does a Vacuum Cleaner Cord work?

That’s actually a very good question as the cord isn’t just wound up on a reel as it also needs to be connected to the motor somehow. If it was just wound up around a reel with one end connected to the motor then any turning of the reel would twist the cord between the reel and the motor till it pulled out of it’s terminals. If you wrap the cord around the reel in opposing directions then it would just unwind from both ends simultaneously and you would have a tangle of cord inside the machine whenever you pulled the cord out.

One way around this is to not connect the leads to anything inside the vacuum cleaner but to concentric conductive circles on the reel itself, then brush or button contacts that are connected to the inner workings of the vacuum cleaner can ride on these conductors and pick up the power much as an electric train picks up power from the overhead wires or third rail. Of course having ring conductors and contacts does not always make for a reliable power connection and runs the risk of sparking so this is a less then ideal solution.

Another solution would be have the takeup reel matched with a moving bracket. The midpoint of the cord is anchored on the reel and then wound up such that both ends play out when unreeled, by winding the slack that is to remain within the appliance closer to the reel’s center of rotation while the end being played out to the outside world on a larger diameter section, the amount of slack that must remain in the appliance housing is minimized and it’s wrapped back and forth across the moving bracket which moves apart to house that slack that must remain in the housing. This allows the cable to be firmly and reliably connected to terminals in the vacuum cleaner but at a greater cost.

You can demonstrate how the moving bracket works by using pulley blocks and showing how moving the pulley blocks apart slightly takes up a fair bit of rope wrapped around the pulleys or by wrapping a string around two pencils and showing how more string is taken up by moving the pencils apart.

You can demonstrate how the concentric storage works by sticking a pencil into a styrofoam cup, then holding the midpoint of a string onto the pencil, wrap one end around the cup while the other end around the pencil, both in the same direction and showing how when you unreel string from the cup, only a little unreels from the pencil.

4 COMMENTS

Storm T August 8, 2011 At 10:52 pm

When you press the button, the cord jumps back because when you press the button, it is like a lever letting the cord go so it will jump back.
James K August 8, 2011 At 10:52 pm

It supplies electricity to the vacuum…Just like any other electrical cord does for lights and other appliances…Odd question
john h August 8, 2011 At 10:52 pm

The same way a retracting tape measure works window blinds etc… When you pull the cord it tightens a spring. the spring locks untill you release the button and it winds up.
John W August 8, 2011 At 10:52 pm

That’s actually a very good question as the cord isn’t just wound up on a reel as it also needs to be connected to the motor somehow. If it was just wound up around a reel with one end connected to the motor then any turning of the reel would twist the cord between the reel and the motor till it pulled out of it’s terminals. If you wrap the cord around the reel in opposing directions then it would just unwind from both ends simultaneously and you would have a tangle of cord inside the machine whenever you pulled the cord out.

One way around this is to not connect the leads to anything inside the vacuum cleaner but to concentric conductive circles on the reel itself, then brush or button contacts that are connected to the inner workings of the vacuum cleaner can ride on these conductors and pick up the power much as an electric train picks up power from the overhead wires or third rail. Of course having ring conductors and contacts does not always make for a reliable power connection and runs the risk of sparking so this is a less then ideal solution.

Another solution would be have the takeup reel matched with a moving bracket. The midpoint of the cord is anchored on the reel and then wound up such that both ends play out when unreeled, by winding the slack that is to remain within the appliance closer to the reel’s center of rotation while the end being played out to the outside world on a larger diameter section, the amount of slack that must remain in the appliance housing is minimized and it’s wrapped back and forth across the moving bracket which moves apart to house that slack that must remain in the housing. This allows the cable to be firmly and reliably connected to terminals in the vacuum cleaner but at a greater cost.

You can demonstrate how the moving bracket works by using pulley blocks and showing how moving the pulley blocks apart slightly takes up a fair bit of rope wrapped around the pulleys or by wrapping a string around two pencils and showing how more string is taken up by moving the pencils apart.

You can demonstrate how the concentric storage works by sticking a pencil into a styrofoam cup, then holding the midpoint of a string onto the pencil, wrap one end around the cup while the other end around the pencil, both in the same direction and showing how when you unreel string from the cup, only a little unreels from the pencil.

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