Referring to
A ruler-guider 20 plugs in the band saw machine 10 over the bench 12 and parallel with the moving direction of the band saw 11. There is a mesh portion 21 along the long axis on one side of the ruler-guider. The ruler-guider can be a gear row or a worm. There is a holder 22 on the extending end of the ruler-guider to reduce the vibration of the band saw.
An active wheel 30 pivots in the band saw machine and gears with the mesh portion 21 of the ruler-guider. Depending on the ruler-guider, the active wheel can be a gear or a worm gear.
An axis 40 plugs on the band saw machine 10. One end of the axis extends out of the band saw machine and another end combines with the active wheel 30.
A knob 50 with scales 51 around the surface mounts on the extending end of the axis 40.
According to aforesaid structures, the active wheel 30 can rotate and move the ruler-guider 20 up or down when the knob 50 is rotated by the operator. Meanwhile, the scales around the surface of the knob will change when the knob is rotated. The operator can read the scale on the knob easily and clearly when the scales match up the pointer that sets on the band saw machine. By the way, the scale will not be sheltered anymore and the operator can check the scale directly and easily without bend down his body. The structures of present invention really improve those disadvantages of prior art and increase the operation efficiency.