Auto-buckled motor core laminated riveting force testing mechanism and method

Abstract

The invention relates to an auto-buckled motor core laminated riveting force testing mechanism and method. The problems that the conventional testing mechanism is unfavorable for balanced force measurement and large in test errors and the like are solved. With the adoption of the technical scheme, the testing mechanism comprises a wire thread insert and a tensile tool, wherein an axial wire threadinsert assembling hole is formed in an auto-buckled core; the wire thread insert is arranged in the wire thread insert assembling hole and is screwed with the wire thread insert assembling hole; anda bottom plate of the tensile tool is respectively buckled to two ends of the auto-buckled core and passes through a wire thread insert inner hole corresponding to the bottom plate by virtue of a screw so as to form screw joints in one-to-one correspondence with the wire thread insert. The testing mechanism has the technical effects that the wire thread insert is a whole, is fixed in a core screwhole and is tightly combined with the screw hole, and the overall rigidity of the core thread is excellent. During stretching, tension applied to the screw is transferred to the thread of the core screw hole by virtue of the wire thread insert, the stress of each punch is uniform, and the tensile testing precision is high.

Description

technical field [0001] The invention relates to a test mechanism and a test method for the stacking riveting force of a self-fastening iron core of a motor. Background technique [0002] The self-fastening iron core of the motor stator and the self-fastening iron core of the rotor are both formed by lamination of punched sheets. The punches of each layer are connected into one body through the self-fastening riveting points uniformly distributed along the circumference on the end faces of the adjacent punches. [0003] The riveting point is punched out by the die on the punching sheet, and the riveting point protrudes from one side of the punching sheet and forms a depression on the other side of the punching sheet. The male end of the rivet point of one punch is pressed into the concave end of the other punch rivet point, and the two punches are connected together by friction between the rivet points. [0004] The reliability of the riveting of the self-buckle riveting po...

AI Technical Summary

Problems solved by technology

[0010] 1) Since the punching sheet is very thin, when the iron core is subjected to radial force, the punching sheet at both ends is prone to instability and deformation, and the deformation produces local axial force, which affects the test accuracy

[0011] 2) When the clamping force or expansion force is not perpendicular to the axis of the iron core, there is an axial component of the force on the iron core, which becomes the riveting point to bear the additional load other than the test tensile force, which affects the test accuracy

[0012] 3) The tooling and the inner hole of the iron core or the outer circle must have a long hug or expansion length in order to be fixed reliably. The parts of the iron core that are hugged or expanded by the tooling at both ends cannot be stretched. The punches that are not tightly held or supported by the clamp in the middle are in a free state, and a considerable part of the punches cannot participate in the tensile test, and the error of the test results is relatively large

[0013] 4) Since the punching sheet is very thin, when the tooling and the iron core are fixed, it is difficult for the clamp to reliably and completely clamp the several punching sheets near the end, so that only part of the punching sheet is fixed by the tooling, and the part of the punching sheet is stretched. Uneven stress on each riveting point affects test accuracy

[0014] 5) It is not easy to control the tightness or expansion length between the tooling and the inner hole or outer circle of the iron core. The number of punching pieces of the iron core that can participate in the tensile test is unstable, and the test data cannot represent the actual situation of the iron core.

[0015] 6) The operating efficiency of the tensile test is low and requires high operating ability

[0018] 1) Due to the gap between the stacked punches, the gap between the screw thread and the screw thread is large, the rigidity of the punch is not good, and the force on the punch is uneven when locking and stretching, and the local riveting point Bear additional additional load, affecting test accuracy

[0019] 2) The axial assembly accuracy of the screw is not high

Since the screw length accuracy is not high, and the thickness of the punching sheet is only about 0.5mm, even if the length difference of each fixing screw is only 0.5mm, it will cause a single iron core punching piece to be partially integrated with other punching pieces, and some parts will not be connected. In the case of screw connection, when the iron core is stretched, the force on each riveting point is uneven, which affects the test accuracy

[0020] 3) The wall of the punching piece is thin and the material is soft. When tapping, there may be a local gap on a certain piece of punching piece, so that the combination of the screw and the screw hole is uneven in length, and the local riveting point bears additional additional load, which affects the test accuracy.

[0021] 4) The iron core is composed of superimposed punched sheets, and the screw holes are processed on it. The threads are discontinuous. When the screws are screwed in, the screw-in resistance is inconsistent. Tighten the screws with approximately the same torque, and the screw-in depth may vary greatly. In the case of subparagraph 2) above

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