34results about How to "Low roundness" patented technology

A rotating portion of a motor includes a magnet, a yoke, and a hub. An upper portion of the yoke is fixed to the hub. The yoke includes a first inner circumferential surface radially opposite to an outer circumferential surface of the magnet with a first gap intervening therebetween, and a second inner circumferential surface radially opposite to the outer circumferential surface of the magnet with a second gap intervening therebetween below the first inner circumferential surface. The second inner circumferential surface is parallel or substantially parallel to the outer circumferential surface of the magnet, and is located radially outward of the first inner circumferential surface. An adhesive is provided in at least a portion of the first gap. No adhesive is provided in at least a lower axial end portion of the second gap.

The invention discloses a casting system and casting method of a cylinder barrel. The casting system comprise a casting mold cavity and a pouring system, wherein the casting cavity comprises a cylinder barrel cavity body, a through hole is axially formed in the cylinder barrel cavity body, the cylinder barrel cavity body is composed of a cylinder barrel head part and a middle body part, the diameter of the cylinder barrel head part is larger than that of the middle body part, a radial protruding block is arranged on the cylinder barrel head part, and a supporting fixing hole and an oil passagehole are formed in the protruding block; the pouring system comprises a sprue, a transverse runner and an inner sprue, the sprue vertically communicates with the transverse runner, the two ends of the transverse runner communicate with the inner sprue through risers, and the inner sprue communicates with a convex block of the casting cavity; and the supporting fixing hole is filled with a first sand core, and an axial through hole of the cylinder barrel cavity body is filled with a second sand core. The casting system has the advantages that parts with the wall thickness of a casting are notprone to shrinkage and loosening defect generating, particularly, the casting defect is not easy to occur among the supporting fixing hole, the oil passage hole and the inner surface of the cylinder barrel, and a chill structure cannot be easily generated in parts with the thin wall thickness.

The invention discloses a method for planning a hole-making process trajectory of a laminated material, which comprises the following steps: 1) dividing the processing process of the laminated material into processing stages such as entry, stabilization, interface, and exit along the axial direction; 2) measuring and sorting out the hole-making accuracy 3) Analyze the variation law of the hole making precision at each stage, and establish the fitting relationship between the hole diameter deviation, roundness and the characteristic parameters of the spiral trajectory; 4) The average value of the axial cutting force is the smallest, and the peak value of the circumferential cutting force is the smallest As the goal, the optimal value of the characteristic parameters of the spiral trajectory is obtained. The invention provides a way to solve the problem of "inverted cone" in the through-hole processing of laminated materials. By analyzing the variation law of the hole-making precision in the key stage of the single-hole processing process, the core goal is to meet the precision level requirements of the export stage, and the spiral movement is carried out. Trajectory planning, and finally realize the optimization of process parameters, which can not only improve the overall hole-making accuracy of the single-hole machining process, but also help reduce the overall cutting force level to prolong the tool life.