One shot switch using flip flop

[Obmar]

Hi everyone,
I am trying to control pneumatic cylinder valves using a push button switch. The cylider has limit switches on both ends of stroke. On pressing the push button, the cylinder has to extend and on signal from end limit change over to reversed solenoid so as to return to original position (where first limit switch gets pressed). As the strting and end conditions are same, pressing push button often results in multiple strokes. I am thinking of using an electronic latch using 4027 JK Flip Flop. But reading through the data sheet, I cannot figure out how (and why) the clock to be used. Can I use this JK Flip Flop without clock input?

By the way, I have tried RS latch with two NOR gates, but cannot avoid 1,1 input status that is not allowed.

Thanks.

 

[Papabravo]

Your only chance to use a JK flip-flop without a clock is if they have asyncronous preset and clear. In that case tie J, K and clock high.

 

[Iawia]

in school they teach us the usefulness of the jk flip flop. however, the clock was never introduced. what is it for? to make sure inputs Q and Q' are triggered simultaneously?

 

[crutschow]

in school they teach us the usefulness of the jk flip flop. however, the clock was never introduced. what is it for? to make sure inputs Q and Q' are triggered simultaneously?

In typical operation the J and K inputs are changed between clock pulses and then the FF changes output state (both Q and Q' change at the same time) with the clock. This allows the logic states to properly propagate in a logic system, avoiding a "race" condition.

 

[crutschow]

Your problem may be better resolved by either using a debounce circuit (google) or a 555 connected as a one-shot to give only one pulse per button push.

 

[colin55]

You have not explained the problem nearly clearly enough.
Why does the push button result in multiple strokes?

What voltage is on the switch?
Does the switch take the circuit HIGH or LOW?

 

[Mikebits]

You have not explained the problem nearly clearly enough.
Why does the push button result in multiple strokes?

Most likely switch bounce. BTW, this thread was started about 4 years ago...

 

[carbonzit]

Most likely switch bounce. BTW, this thread was started about 4 years ago...

You mean those poor little pneumatic cylinders are still running multiple strokes?

 

[crutschow]

Dang. Suckered again.

 

[Ian Rogers]

Not really Carl.... Iawia has asked a specific question about the JK flipflop and the clock operation (albeit in a four year old thread)..