General Catalog - NB - #251

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ACTUATOR ACTUATOR H-10 H-11 ACCURACY Table H-7 shows accuracy of BG type. Table H-7 Accuracy part number rail length mm high ìm positioning repeatability BG20 BG26 BG33 BG46 BG55 precision ìm high ìm positioning accuracy precision ìm high ìm running parallelism B precision ìm precision ìm backlash high ìm high N�Em �¦starting torque precision N�Em 100 150 200 150 200 250 300 150 200 300 400 500 600 340 440 540 640 740 840 940 1,040 1,140 1,240 980 1,080 1,180 1,280 1,380 ±3 ±3 ±3 �i�}5�j ±3 �i�}5�j ±3 ±1 ±1 ±1 �i�}3�j - ±1 �i�}3�j - ±1 - 50 50 30 35 40 70 35 40 50 80 100 80 100 20 20 15 20 25 - 20 25 30 - 35 40 - 25 25 25 35 35 40 50 50 10 10 10 15 - 15 20 - 25 30 - 5 5 5 5 5 2 2 2 - 2 - 2 - 0.01 0.015 0.07 0.10 0.12 0.012 0.04 0.15 - 0.15 0.17 - 0.17 0.20 - Above values are measured by using our selected motors. �¦ Above specifications are based on using NB standard grease. Other grease may cause deviations. The values in the parentheses are positioning repeatability when used with return pully unit. Positioning Repeatability After setting an arbitrary position, from one end, move the drive block to this position and measure the stop position. Repeat the positioning and measurement process 7 times with respect to the setting position at the midpoint and near both ends of travel. Take the maximum difference and divide it by 2, then indicate it with a positive and negative sign as the test result. Positioning Accuracy Positioning is performed in one direction and the resulting position is set as the datum point. Take the difference between the actual travel distance and the commanded travel distance from the datum point. Continuing in the same direction (without returning to the start point) repeat this process randomly several times until nearing to the stroke limit. Express the accuracy by the absolute maximum difference. Running Parallelism B After fixing the guide rail onto the surface plate, placing the dial test indicator on the center of the slide block and connecting the indicator probe onto the mounting surface, run the block over the entire travel distance. Take the maximum deviation in readings as the test result. Backlash Using the feed screw to move the slide block a little, take the dial test indicator reading and make it the datum point. While in this position, thrust the block by a certain force in the same direction without using the feed screw. Release the thrust and read the return, then take the difference from the datum point. Repeat the same process at the midpoint and near both ends of travel. Take the maximum difference as the test result. Positioning Repeatability 12 �i�imaximum value of n�j�|�iminimum value of n�j�j Positioning Accuracy���iÄn�jmax Backlash��Ä Figure H-7 Positioning Repeatability 1 2 3 n Figure H-8 Positioning Accuracy �{ �| = (actual distance) -(commanded distance) travel distance Ä1 Ä2 Ä3 Än Figure H-9 Running Parallelism Figure H-10 Backlash move by feed screw thrust displacement return Ä ���}