the use of an accumulator attached to a chamber of a cylinder allows for the reduction in pressure spikes in constant force hydraulic control systems . constant force hydraulic control systems often use a differential pressure valve that may have a reaction time of up to one second . by using the accumulator , pressure spikes which might have occurred in the past can be smoothed out and reduced , thus preventing damage to a workpiece or agricultural product . additionally , by using two cylinders of different sizes , in which one of the cylinders has a barrel end with the approximately the same area as the rod end of the larger cylinder , coordination of devices attached to the cylinders can be maintained without a mechanical link when the hydraulic control system is in a manual mode .