Electric toothbrush head and assembly method therefor

1 . An electric toothbrush head, comprising:

a housing, defined with a mounting chamber and an accommodating chamber, wherein the accommodating chamber is connected to the mounting chamber;

a brush head assembly, comprising a bracket and a bristle planting head, wherein the bracket is fixedly disposed inside the mounting chamber, the bracket is defined with a matching hole, the bristle planting head comprises a rotary connecting part, a limiting part and a linkage shaft, the rotary connecting part is rotatably matched with the matching hole, the limiting part is connected to the rotary connecting part, and the linkage shaft is disposed on the limiting part and eccentrically disposed relative to the rotary connecting part;

a driving assembly, comprising a push rod and an elastic piece, wherein the push rod is movably disposed inside the accommodating chamber, an end of the push rod is rotatably connected to the linkage shaft, another end of the push rod is configured to match with an external main shaft, and the elastic piece is disposed inside the mounting chamber and configured to drive the push rod to move facing away from the linkage shaft; and

wherein the bristle planting head comprises a bristle planting disc, and the bristle planting disc is connected to an end of the rotary connecting part facing away from the limiting part; the bracket comprises a matching part, the matching hole is defined in the matching part, the matching part is disposed between the bristle planting disc and the limiting part, and a cross-sectional area of the limiting part is larger than that of the matching hole.

2 . The electric toothbrush head as claimed in claim 1 , wherein the bracket comprises an abutting part, the abutting part is disposed on a side of the matching part facing toward the bristle planting disc and protrudes relative to a surface of the matching part, and a cross-sectional area of the abutting part is smaller than an area of an end surface of the matching part facing toward the bristle planting disc.

3 . The electric toothbrush head as claimed in claim 1 , wherein a distance between the matching part and the bristle planting disc gradually decreases along a radial direction of the matching hole.

4 . The electric toothbrush head as claimed in claim 1 , wherein a notch is defined on a side surface of the bracket, the notch is connected to the matching hole, a minimum distance of two ends of the notch is smaller than a diameter of the rotary connecting part, and the notch is configured to allow the rotary connecting part to pass through and move into the matching hole.

5 . The electric toothbrush head as claimed in claim 4 , wherein a width of the notch gradually increases along a direction facing away from the rotary connecting part.

6 . The electric toothbrush head as claimed in claim 1 , wherein the bracket comprises first fixing parts, the first fixing parts are disposed on a side of the bracket facing toward a bottom wall of the mounting chamber, the first fixing parts are provided with guiding surfaces and accommodating grooves, the accommodating grooves are defined between the guiding surfaces and the bristle planting head, the accommodating grooves are defined by recessing toward a side facing toward the rotary connecting part with positions of tail parts of the guiding surfaces as references, respectively; second fixing parts are disposed on a chamber wall of the mounting chamber at positions corresponding to the accommodating grooves, the second fixing parts are clamped and matched with the accommodating grooves, respectively, and each of the second fixing parts is partially located between two side walls of a corresponding one of the accommodating grooves along a circumferential direction of the rotary connecting part.

7 . The electric toothbrush head as claimed in claim 6 , wherein two convex structures are disposed on the chamber wall of the mounting chamber at positions corresponding to two sides of each of the first fixing parts, a limiting groove is defined between the two convex structures, each of the first fixing parts is at least partially disposed inside the limiting groove, and the limiting groove is configured to limit rotation of a corresponding one of the first fixing parts along the circumferential direction of the rotary connecting part.

8 . The electric toothbrush head as claimed in claim 1 , wherein a limiting step is disposed on the housing at an opening of the mounting chamber, and the limiting step is configured to abut against a lower end surface of the bracket.

9 . The electric toothbrush head as claimed in claim 1 , wherein a first positioning part is disposed on a chamber wall of the mounting chamber, the push rod is provided with a second positioning part, an end of the elastic piece is abutted against the first positioning part, another end of the elastic piece is connected to the second positioning part, and the elastic piece is disposed on an extension side of the push rod.

10 . The electric toothbrush head as claimed in claim 9 , wherein the elastic piece is a spring or an elastic plate.

11 . The electric toothbrush head as claimed in claim 1 , wherein the elastic piece is a first torsion spring, the first torsion spring comprises a first connecting end, a torsion spring body, and a second connecting end, the first connecting end is connected to an end of the torsion spring body, and the second connecting end is connected to another end of the torsion spring body, the bracket is defined with a first connecting hole, the first connecting end is matched with and connected to the first connecting hole, the torsion spring body is sleeved on a periphery of the limiting part, the limiting part is defined with a second connecting hole, and the second connecting end is matched with and connected to the second connecting hole.

12 . The electric toothbrush head as claimed in claim 1 , wherein the elastic piece is a second torsion spring, a first connecting column is disposed on the bracket, a positioning column is disposed on the limiting part, the second torsion spring comprises a third connecting end and a fourth connecting end, the third connecting end is sleeved on a periphery of the first connecting column, and the fourth connecting end is sleeved on a periphery of the positioning column.

13 . The electric toothbrush head as claimed in claim 12 , wherein the second torsion spring comprises a first torsion part and a second torsion part, an end of the first torsion part is connected to the third connecting end, another end of the first torsion part is connected to an end of the second torsion part, the first torsion part extends to a rotation axis of the rotary connecting part along a radial direction of the rotary connecting part, an accommodating hole is defined at a center of the limiting part, the second torsion part is at least partially disposed inside the accommodating hole, and another end of the second torsion part is connected to the fourth connecting end.

14 . The electric toothbrush head as claimed in claim 1 , wherein a second connecting column is disposed on a bottom of the mounting chamber, the elastic piece is a third torsion spring; the third torsion spring comprises a fixed abutting section, a first spiral section, and a first elastic driving rod sequentially connected in that order; the fixed abutting section is abutted against a chamber wall of the mounting chamber, the first spiral section is sleeved on a periphery of the second connecting column, the bristle planting head is provided with an abutting structure, and the first elastic driving rod is abutted against a side surface of the abutting structure.

15 . The electric toothbrush head as claimed in claim 1 , a third connecting column is disposed on a bottom of the mounting chamber, the third connecting column is concentrically disposed relative to the rotary connecting part; the third connecting column is defined with a first positioning groove; the elastic piece is a fourth torsion spring, the fourth torsion spring comprises a rotation stopping part, a second spiral section and a second elastic driving rod sequentially connected in that order; the rotation stopping part is matched with the first positioning groove, the second spiral section is sleeved on a periphery of the third connecting column, and the second elastic driving rod is connected to the limiting part to thereby drive the limiting part to rotate.

16 . The electric toothbrush head as claimed in claim 15 , wherein a fourth connecting column is disposed on the limiting part, the fourth connecting column is eccentrically disposed relative to the rotary connecting part, the fourth connecting column is defined with a second positioning groove, the second positioning groove extends along an axial direction of the rotary connecting part, the second positioning groove extends along a radial direction of the rotary connecting part, and the second elastic driving rod is movably disposed inside the second positioning groove.