Create Bone Constraints Other Than Angle

[DaiBach]

I am a Debut 8 user and have created a bone rig using control bones to have eyes blinking winking etc. The problem I have is I am using the "Translate Bone" tool to operate the controlling bone which moves the top and bottom eyelids at the same time. It is very fiddly to stop at the closed point. Moving the bone too far causes the masking to open the eye again with the bottom lid above the top lid. When a rig's movement is controlled by manipulating bones the angle constraint setting provide limits. Is there any way of providing limits for bones that are translated and not rotated?