Installing the ball screw on the X axis

1) Fitting the bearing cap in the rear of the bearing housing on site

① Fit 50ATC angular contact bearing into B26270042A 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 B26270053 bearing cap before fitting it on-site.

※ Target size of the bearing cap “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) Fitting the bearing cap in the front of the bearing housing on site

① Fit 50ATC angular contact bearing into B26270032 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 of B26270053 bearing cap before fitting it on-site.

※ Target size of the bearing cap “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

“A” “B” Bearing

Cap

Bearing Housing

“A” “B” ^{Spacer Bearing}

Cap

3) Installing the ball screw

Install the ball screw into the bearing housing before inserting B14220073 spacer. Then, tighten the lock nut.

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

4) Installing the bearing housing assembly

Use the crane to lift up the ball screw and bearing housing assembly with care of the center of gravity. Push it in through the X-axis ball screw place of the table with care.

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

5) Fixing the bearing housing.

Tighten B26270032 bearing housing bolts and insert the positioning pins.

▪ 8-BB16×60, 4-TPB-16×56

Lock-Nut Bearing

Housing Spacer

Screw Area Spacer

Fixing Bolt

Position Pin Bearing Housing

6) Runout on the ball screw

① Present 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.

7) Tightening the lock nut in the rear of the bearing housing

Insert B14220073 spacer at the end of the ball screw (where B26270042A 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.

8) Pre-tension on the ball screw

① Turn the ball screw nut back to the original and tighten the fixing bolts.

▪ 6-BB 12×30

② Install the screw jack under the ball screw nut and correct the parallelism for the ball screw (either ends, center, horizontal and vertical position)

▪ Install the indicator on the right-angle block and present the needle at the end of the ball screw. And set it to 0. Use the screw jack to adjust the vertical and horizontal parallelism to below 0.02mm respectively.

③ Present the needle at the end of the ball screw and set it to 0. Use the chisel and hammer 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 collar and fit it on site.

▪ The collars for adjusting the pre-tension are located on either sides so you can remove them easily by simply loosening the lock nut.

※ Pre-tension on the X-axis ball screw: 0.28mm

Spacer Lock

9) Runout on the ball screw (installed in the bracket).

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 0.01 mm, tighten up the set-screw for locking the lock-nut.

10) Tightening the ball screw nut

Install the screw jack under the ball screw nut as instructed above and correct the

parallelism for the ball screw (either ends, center, horizontal and vertical position). Then, tighten up the bolts on the ball screw nut.

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

※ If the measuring tools are not available, turn on the machine and move the X axis to

"X0". Then, apply force as even as possible to each bolt diagonally until you tighten them up finally.

Collar

Lock Bracket Nut

Right-angle Block

Screw Jack

Indicator

11) 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 Aligning between servo motor and ball screw

Install the indicator on the rectangle block in the X-axis bed guide way side, align the servo motor shaft with the ball screw and tighten up the bolts.

▪ Target Concentricity: below 0.01 mm both horizontally and vertically

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

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

▪ Runout Tolerance: below 0.01mm

12) Finishing

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

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

Coupling

Coupling

Clamping Bolt Vertical Horizontal