Two tricky problem encountered in the repair process of starting the motor shaft, one bearing outer ring and the fork bearing hole with the gap of process, and second is to measure the cross pin and the bearing outer ring axial clearance.

Drive motor shaft bearing bore prong is the overall structure, with a screw to prevent rotation. Hole and bearing with the transition should fit its structure K7 / h6, gap 0.017-0.032mm. In the actual repair found prong bearing holes due to wear, the pore size becomes large and round loss, motor testing but will not wear the bearing outer ring hole.

Since the installation from the outside to the inside of the bearing load, often start loading proper gap, but the gap is too large when mounted in place. Therefore, you can use when servicing electrical plating method, the bearing hole wear parts for local electricity brush treatment to the bearing hole to return to the state before abrasion test drive, the required size. Cylindrical should be no greater than 0.02 as well, with the gap between the guaranteed 0.017-0.032mm. But it notes that when plating, not the bath ring touches the outside of the bearing hole, otherwise it can not load bearing.

Cross pin to the gap should be less than required to 0.05mm, but the gap with the ends of the bearing sleeve thickness, both ends of the nylon pad thickness, the thickness of the ring, snap ring groove width, length and ends of the cross pin prong bearing bore length related. Depending on the size chain calculation and the error superposition principle, to measure the relevant dimensions eleven and then calculated, would have a significant error. Thus, piece by piece measurement is not desirable.

Only the ends of the bearing ring and bearing into the bearing bore Zhoucun sofa, measuring the total length and the bottom ends of the cross pin bearing length, then calculate the optional nylon pad. However, to measure the length of the bottom bearing except special measuring tools, the common measure the depth and length of the micrometer is difficult to measure the exact value.