Abstract: A toothbrush includes a brush head linkage (100), a connecting mechanism (200) and a toothbrush handle (300); the connecting mechanism (200) includes a first connector (210), a second connector (220) and an elastic structural element (230) connected to the second connector (220); the first connector (100) is rotatably connected to the second connector (220), and the axis of rotation extends in a front-rear direction; and the elastic structural element (230) includes at least one return torsion spring (231), the return torsion spring (231) includes a helix spring (2311) in the form of a cylinder with an opening of the cylinder oriented in a direction parallel to an extension direction of an oscillating reference line, the helix spring is in stop fit with the second connector (220) in a direction perpendicular to the oscillating reference line, and the return torsion spring further includes a first torsion bar (2311) and a second torsion bar (2312) respectively connected to a front end and a rear end of the hel

Abstract: A head module capable of reciprocal rotation for an electric cleaning apparatus comprises cleaning elements, a housing and a driven rod disposed in a hollow inner cavity of the housing, wherein the rod is provided with a hollow cavity body for accommodating a drive shaft; at least one gap is provided in a region surrounding the hollow cavity body; at least one inner side notch is distributed on a side wall of the inner cavity, for accommodating a protrusion; the rod further comprises a partially cylindrical or conical cavity body region. When the drive shaft is not yet inserted into the rod, there is a gap between the notch and the protrusion in a direction perpendicular to the rotation axis (L1) of the drive shaft. The length of the gap is greater than or equal to the amount of single-side interference between the rod and the drive shaft.