Installing the ball screw on the Y axis

housing

① Fit 50ATC angular contact bearing into B26290042A bearing housing, and measure the depth between end point of the bearing and top section of the bearing housing. (“A”)

② Calculate the target size of B26270053A bearing cap before fitting it on-site.

※ “B” = “A” + 0.05mm

③ Insert the completed bearing cap into the bearing housing (where 50TAC bearing is installed).

※ Put force as even as possible to each of the fixing bolts.

▪ 8-BB12×35

2) Installing the bearing cap in the upper bearing housing

① Fit 50ATC angular contact bearing into

B26290032 bearing housing, and measure the depth between end point of the bearing and top section of the bearing housing. (“B”)

② Calculate the target size ("A") of B26290083 bearing cap before fitting it on-site.

※ “A” = “B” + 0.05mm

③ Insert the completed bearing cap into the bearing housing (where 50TAC bearing is installed).

※ Put force as even as possible to each of the fixing bolts.

▪ 8-BB12×35

3) Installing the ball screw into the upper bearing housing

Install the ball screw and insert B13210113 collar (with P50 O-ring inserted) into the bearing housing. Then, tighten the lock-nut.

※ To the end, you must solve the run-out problem

“A”“B”

screw to the full length at this moment.

4) Installing the ball screw and bearing housing assembly

① Insert G50 O-ring into B26210114A spacer with grease applied, and install the spacer at the end of the ball screw.

② Fit the adjusting collars (x6) into the bolt holes in the bearing housing based on the marking number for each bolt.

③ Use the crane to lift up the ball screw and bearing housing assembly while keeping it balanced.

④ Push in the assembly through the Y-axis ball screw place in the spindle head.

⑤ When installing the ball screw in the opposite bearing housing, take caution lest that either end of the ball screw get scratched.

⑥ Right before it is inserted to the full, insert the positioning pins (4-TPB-13×70) and tighten the bearing housing bolts (6-BB16×60).

Spacer

Screw Area

Screw Area

Fixing Bolt Adjusting

Collar

Bearing Housing Spacer

O-Ring (G50)

5) Runout on the ball screw

① Install the indicator at the end of the ball screw.

② Turn the ball screw manually while reading the indicator, and impact and fix the lock-nut using the chisel at the highest point of the runout.

(intermediate value between highest and lowest)

③ If the runout value of the ball screw goes below 0.002 mm, tighten up the set-screw for locking the lock-nut.

6) Tightening the lock nut on the lower ball screw Insert B14220073 spacer at the end of the ball screw (where B26290042A bearing housing will be

installed), and tighten the lock nut.

※ To the end, you must do the pre-tension work and solve the run-out problem with the ball screw so you just tighten the screw to the full length at this moment.

7) Pre-tension on the ball screw

Present the needle at the end of the ball screw and set it to 0. Use the dedicated tools to loosen the lock nut with minimum damage, and check the gradation changes of the indicator gauge. If the measurement does not fall into the tension target, remove the spacer from the bearing housing and fit it on site.

※ Pre-tension on the Y-axis ball screw: 0.10mm

Bearing Housing

Lock-Nut Spacer

Bearing Housing

Lock-Nut Spacer

8) Runout on the lower ball screw

① Present the indicator on the block at the end of the ball screw.

② Turn the ball screw manually while reading the indicator, and impact and fix the lock-nut using the chisel at the highest point of the runout.

(intermediate value between highest and lowest)

③ If the runout value of the ball screw goes below 0.001 mm, tighten up the set-screw for locking the lock-nut.

9) Installing the servo motor

① Insert the coupling into the servo motor shaft or gear box shaft, and install the servo motor into the bearing housing.

▪ Tighten the bolts slightly because you have yet to perform the alignment between servo motor and ball screw.

② Install the indicator on the rectangle block in the column guide way side, align the servo motor shaft with the ball screw and tighten up the bolts.

▪ Based on the horizontal and vertical positions of the ball screw, move the servo motor to adjust the concentricity of the servo motor shaft to below 0.01mm.

③ Position the coupling in the middle between ball screw and motor shaft.

▪ If the servo motor aligns properly with the ball screw, it will be inserted into the ball screw smoothly.

④ While rotating the ball screw, tighten the clamping bolts and correct the runout on the coupling.

▪ Runout Tolerance : below 0.01mm

Coupling Coupling

⑤ When installation is done, connect the lubrication pipe, servo motor cable (power and feedback cables) connector and various covers back to the original.

10) Tightening the ball screw nut

① Turn on the machine and move the Y axis to

“Y0”.

② Put force as even as possible to each bolt until you tighten them up finally.

▪ Alternatively, you can tighten up two diagonal bolts first and loosen them slightly. Then, tighten them up finally.

※ If you had removed and re-installed the Y-axis ball screw, you must reset the reference point for the Y axis.

Ball Screw Nut Bolt

4.6 Resetting the reference point for the Y axis (Y-axis stroke: 2000mm)