PURPOSE: To make a device perform such an efficient infeed speed as commensurate to the cutting length varied every moment in a cutting work as well as to check heavy-duty cutting that may entails damage to a tool, before it happens.

CONSTITUTION: In case of a well-known horizontal band saw machine 1, pressure oil is fed to a chamber at the piston side of a lifting cylinder 7, making a piston rod 39 operate for its extension. Another pressure oil inside a chamber at the piston side of a lifting cylinder 37 is discharged therefrom, making a cutting head 5 go down with its own weight. Therefore, a proper control valve is set up in the discharge passage connected to the chamber at the piston side of the cylinder 37 and with this control valve, proper adjustment is carried out so that infeed of a saw blade 29 to a cutting work W can be properly controlled.