Stator assembly and torque measuring device

1. A stator assembly comprising:

a stator holder;

a first stator which includes a first body making contact with an upper end of the stator holder and a plurality of first teeth extending from the first body so as to be disposed inside the stator holder;

a second stator which includes a second body making contact with a lower end of the stator holder and a plurality of second teeth extending from the second body so as to be alternately aligned with the first teeth inside the stator holder; and

a fusion-welded material that is fusion-welded to the stator holder and the first and second bodies,

wherein the stator holder has a cylindrical shape, and the first and second teeth make contact with an inner circumferential surface of the stator holder, and

wherein the stator holder is provided at the inner circumferential surface thereof with spaces, and each of the first and second teeth is separately inserted into each of the spaces.

2. The stator assembly of claim 1 , wherein the fusion-welded material is fused by heat or an ultrasonic wave.

3. The stator assembly of claim 1 , wherein the first and second bodies have widths narrower than widths of the upper and lower ends of the stator holder, respectively, and the fusion-welded material is disposed at a border area between the first body and the upper end of the stator holder, and at a border area between the second body and the lower end of the stator holder.

4. The stator assembly of claim 1 , wherein the first and second bodies have a coupling hole, and the fusion-welded material is disposed to the first and second bodies and the upper and lower ends of the stator holder through the coupling hole.

5. The stator assembly of claim 1 , wherein the stator holder is provided with a protrusion having a ring shape which protrudes from an outer peripheral surface of the upper and lower ends of the stator holder, the first and second bodies make contact with an inner circumferential surface of the protrusion, and the fusion-welded material is formed by fusing the protrusion.

6. The stator assembly of claim 5 , wherein the protrusion has a material identical to a material of the stator holder, and is integrally formed with the stator holder.

7. A stator assembly comprising:

a stator holder;

a first stator which includes a first body making contact with an upper end of the stator holder, a plurality of first teeth extending from the first body so as to be disposed inside the stator holder, and a first coupling rim extending from the first body so as to be coupled to a first outer portion of the stator holder; and

a second stator which includes a second body making contact with a lower end of the stator holder, a plurality of second teeth extending from the second body so as to be alternately aligned with the first teeth inside the stator holder, and a second coupling rim extending from the second body so as to be coupled to a second outer portion of the stator holder,

wherein the stator holder has a cylindrical shape, and the first and second teeth make contact with an inner circumferential surface of the stator holder, and

wherein the stator holder is provided at the inner circumferential surface thereof with spaces, and each of the first and second teeth is separately inserted into each of the spaces.

8. The stator assembly of claim 7 , wherein the first coupling rim makes contact with an outer circumferential surface of the stator holder, and the second coupling rim makes contact with the outer circumferential surface of the stator holder.

9. The stator assembly of claim 8 , wherein the first and second coupling rims are caulked so as to be coupled to the stator holder.

10. The stator assembly of claim 8 , wherein the upper end of the stator holder has a first protrusion rim protruding radially outward, the lower end of the stator holder has a second protrusion rim protruding radially outward, the first coupling rim is calked so as to be coupled to the first protrusion rim, and the second coupling rim is calked so as to be coupled to the second protrusion rim.

11. The stator assembly of claim 8 , wherein the upper end of the stator holder has a first protrusion rim protruding radially outward, the lower end of the stator holder has a second protrusion rim protruding radially outward, the first coupling rim is bent so as to be coupled to the first protrusion rim, and the second coupling rim is bent so as to be coupled to the second protrusion rim.

12. A torque measuring device comprising:

a case:

a magnet disposed in the case, the magnet being coupled to an input shaft rotated by external force so as to be rotated;

a stator assembly disposed in the case to surround the magnet, the stator assembly being coupled to an output shaft connected to the input shaft through a torsion bar so as to be rotated; and

a sensor which detects variation of a magnetic field generated between the magnet and the stator assembly, wherein the stator assembly includes:

a stator holder;

a first stator which includes a first body making contact with an upper end of the stator holder and a plurality of first teeth extending from the first body so as to be disposed inside the stator holder;

a second stator which includes a second body making contact with a lower end of the stator holder and a plurality of second teeth extending from the second body so as to be alternately aligned with the first teeth inside the stator holder; and

a fusion-welded material that is fusion-welded to the stator holder and the first and second bodies,

wherein the stator holder has a cylindrical shape, and the first and second teeth make contact with an inner circumferential surface of the stator holder, and

wherein the stator holder is provided at the inner circumferential surface thereof with spaces, and each of the first and second teeth is separately inserted into each of the spaces.

13. A torque measuring device comprising:

a case:

a magnet disposed in the case, the magnet being coupled to an input shaft rotated by external force so as to be rotated;

a stator assembly disposed in the case to surround the magnet, the stator assembly being coupled to an output shaft connected to the input shaft through a torsion bar so as to be rotated; and

a sensor which detects variation of a magnetic field generated between the magnet and the stator assembly, wherein the stator assembly includes:

a stator holder;

a first stator which includes a first body making contact with an upper end of the stator holder, a plurality of first teeth extending from the first body so as to be disposed inside the stator holder, and a first coupling rim extending from the first body so as to be coupled to a first outside of the stator holder; and

a second stator which includes a second body making contact with a lower end of the stator holder, a plurality of second teeth extending from the second body so as to be alternately aligned with the first teeth inside the stator holder, and a second coupling rim extending from the second body so as to be coupled to a second outside of the stator holder,

wherein the stator holder has a cylindrical shape, and the first and second teeth make contact with an inner circumferential surface of the stator holder, and

wherein the stator holder is provided at the inner circumferential surface thereof with spaces, and each of the first and second teeth is separately inserted into each of the spaces.