This video is made when the workers are operating press brake.They are using this machine to bend big sheet metal.You also can see several steps of operation.It is a good lesson for new persons.If you want to study how to run press brake,please kindly see it.
Each press brake operator is familiar with the operation and maintaining of this machine.But we think most people do not have more knowledge for the motion trace.The understanding for motion trace will help you to repair this machine by yourself when sudden thing happen.In some degree,it will benefit your operation when you know the reason of running.You would be easy to find problem if this machine has any damage. The power is from piston on the top of press brake when two cylinders move up and down,the pressure will generate.then,the pressure will press blade into mould to work.
Under free falling body,it does not need to add any force when the blade moves down.This force is changed by the weight of top parts.During this process,the cylinders will add oil and this will speed the movement.There are a brake when blade would touch metal.The style of brake is torsion bar and very advanced in the technical level.
2, Stationary State
There are dead point on the frame of press brake.Its aim is to stop the blade to continue to move down.The system closed the hydraulic cylinder in case the blade damages the dead point.As to dead point,you can search in the google for more professional explanation.
3, Reducing pressure
The hydraulic cylinders would need a short time to reduce the pressure.This process is very stable because digital panel can decide this.It is not allowed to be too quick or too slow.Actually,this is a strong point of hydraulic system.
4, Back pressure
When backpressure begins,the blade will move up to top dead point.In most situation,the speed is very quick due to hydraulic cylinder.There are a direction valve to control this step and fix it on the correct point.
When the blade moves,the bending process has started.The force will forward the blade into mould and then go back due to back pressure.Of course, you can stop the blade to move if you close the cylinders.We would like remind operators not to place too thick metal in the bottom die,other wise,it will break the press brake machine.
The bending would be over when the blade is near to the bottom of mould.There should have a gap between the blade and bottom die in case the touch will damage the machine.
Taking a summary by one word for press brake,the blade moves up and down under the control of hydraulic cylinder.When the blades touch the bottom die,the metal would be bent.