Image forming apparatus and developing cartridge thereof

1. An image forming apparatus, comprising:

a main body;

a driving unit mounted to the main body, the driving unit comprising a driving shaft and a driving coupler connected to the driving shaft, the driving coupler having arranged thereon a plurality of driving tips; and

a consumable unit detachably received in the main body, the consumable unit comprising a rotating body configured to rotate with a driven shaft and a passive coupler connected to the driven shaft, the passive coupler having arranged thereon a plurality of passive tips, corresponding ones of the plurality of driving tips and the plurality of passive tips coming into engaging contact with each other when the consumable unit is operably received in the main body, and the corresponding ones of the plurality of driving tips and the plurality of passive tips maintaining the engaging contact with each other to drive the driven shaft by driving the driving shaft when respective rotational axes of the driving shaft and the driven shaft intersect each other at a non-zero angle.

2. The image forming apparatus according to claim 1 , wherein at least one of the driving coupler and the passive coupler comprises:

a primary coupler coupled to and rotatable with the at least one of the driving shaft and the driven shaft; and

a secondary coupler moveable along a direction of a rotational axis of the at least one of the driving shaft and the driven shaft toward and away from the primary coupler, the secondary coupler being in one or more point-contacts with the primary coupler with respect to a rotational direction of the at least one of the driving shaft and the driven shaft.

3. The image forming apparatus according to claim 2 , wherein the primary coupler comprises a plurality of circumferential projections protruding outwardly from an outer surface thereof, and

wherein the secondary coupler having an inner surface defining a space into which the primary coupler is received, a plurality of accommodating grooves being arranged accommodating on the inner surface, the plurality of circumferential projections of the primary coupler each being receivable into, so as to be in a point-contact with, a respective corresponding one of the plurality of accommodating grooves.

4. An image forming apparatus, comprising:

a main body;

a driving unit mounted to the main body, the driving unit comprising a driving shaft and a driving coupler connected to the driving shaft, the driving coupler having arranged thereon a plurality of driving tips protruding in a direction parallel to a rotation axis of the driving shaft; and

a consumable unit detachably received in the main body, the consumable unit comprising a rotating body configured to rotate with a driven shaft and a passive coupler connected to the driven shaft, the passive coupler having arranged thereon a plurality of passive tips,

wherein corresponding ones of the plurality of driving tips and the plurality of passive tips are in a point-contact with each other with respect to a rotational direction of at least one of the driving shaft and the driven shaft.

5. The image forming apparatus according to claim 4 , wherein the plurality of driving tips and the plurality of passive tips are engaged with each other when the consumable unit is operably received in the main body, and

wherein the corresponding ones of the plurality of driving tips and the plurality of passive tips maintain the engaging contact with each other when respective rotational axes of the driving shaft and the driven shaft intersect each other.

6. The image forming apparatus according to claim 4 , wherein at least one of the driving coupler and the passive coupler comprises:

a primary coupler coupled to and rotatable with the at least one of the driving shaft and the driven shaft; and

a secondary coupler moveable along a direction of a rotational axis of the at least one of the driving shaft and the driven shaft toward and away from the primary coupler, the secondary coupler being in one or more point-contacts with the primary coupler with respect to a rotational direction of the at least one of the driving shaft and the driven shaft.

7. The image forming apparatus according to claim 6 , wherein the primary coupler comprises a plurality of circumferential projections protruding outwardly from an outer surface thereof, and

wherein the secondary coupler having an inner surface defining a space into which the primary coupler is received, a plurality of accommodating grooves being arranged on the inner surface, the plurality of circumferential projections of the primary coupler each being receivable into, so as to be in a point-contact with, a respective corresponding one of the plurality of accommodating grooves.

8. A developing cartridge detachably receivable in a main body of an image forming apparatus which includes a driving shaft that rotationally drives a driving coupler having arranged thereon a plurality of driving tips, comprising:

a frame defining a volume into which developer is received;

an image carrying body rotatably arranged in the frame;

a developing roller rotatably arranged adjacent the image carrying body and configured to convey the developer received in the volume to the image carrying body; and

a passive coupler connected to at least one of respective rotating shafts of the image carrying body and the developing roller, the passive coupler having arranged thereon a plurality of passive tips, the plurality of passive tips arranged such that each of the plurality of passive tips comes into an engaging contact with a respective corresponding one of the plurality of driving tips of the driving coupler of the image forming apparatus when the developing cartridge is operably received in the main body of the image forming apparatus, and the corresponding ones of the plurality of driving tips and the plurality of passive tips maintaining the engaging contact with each other to drive the rotating shaft by driving the driving shaft when respective rotational axes of the driving shaft and the rotating shaft intersect each other at a non-zero angle.

9. The developing cartridge according to claim 8 , wherein at least one of the driving coupler and the passive coupler comprises:

a primary coupler coupled to and rotatable with the at least one of the driving shaft and the rotating shaft; and

a secondary coupler moveable along a direction of a rotational axis of the at least one of the driving shaft and the rotating shaft toward and away from the primary coupler, the secondary coupler being in one or more point-contacts with the primary coupler with respect to a rotational direction of the at least one of the driving shaft and the rotating shaft.

10. The developing cartridge according to claim 9 , wherein the primary coupler comprises a plurality of circumferential projections protruding outwardly from an outer surface thereof, and

wherein the secondary coupler having an inner surface defining a space into which the primary coupler is received, a plurality of accommodating grooves being arranged on the inner surface, the plurality of circumferential projections of the primary coupler each being receivable into, so as to be in a point-contact with, a respective corresponding one of the plurality of accommodating grooves.

11. A developing cartridge detachably receivable in a main body of an image forming apparatus which includes a driving shaft that rotationally drives a driving coupler having arranged thereon a plurality of driving tips protruding in a direction parallel to a rotation axis of the driving shaft, comprising:

a frame defining a volume into which developer is received;

an image carrying body rotatably arranged in the frame;

a developing roller rotatably arranged adjacent the image carrying body and configured to convey the developer received in the volume to the image carrying body; and

a passive coupler which is provided in at least one rotating shaft of the image carrying body and the developing roller and comprises a plurality of passive tips,

wherein corresponding ones of the plurality of driving tips and the plurality of passive tips are in a point-contact with each other with respect to a rotational direction of at least one of the driving shaft and the rotating shaft.

12. The developing cartridge according to claim 11 , wherein the plurality of driving tips and the plurality of passive tips are engaged with each other when the developing cartridge is operably received in the main body of the image forming apparatus, and

wherein the corresponding ones of the plurality of driving tips and the plurality of passive tips maintain the engaging contact with each other when respective rotational axes of the driving shaft and the rotating shaft intersect each other.

13. The developing cartridge according to claim 11 , wherein at least one of the driving coupler and the passive coupler comprises:

a primary coupler coupled to and rotatable with the at least one of the driving shaft and the rotating shaft; and

a secondary coupler moveable along a direction of a rotational axis of the at least one of the driving shaft and the rotating shaft toward and away from the primary coupler, the secondary coupler being in one or more point-contacts with the primary coupler with respect to a rotational direction of the at least one of the driving shaft and the rotating shaft.

14. The developing cartridge according to claim 13 , wherein the primary coupler comprises a plurality of circumferential projections protruding outwardly from an outer surface thereof, and

wherein the secondary coupler having an inner surface defining a space into which the primary coupler is received, a plurality of accommodating grooves being arranged on the inner surface, the plurality of circumferential projections of the primary coupler each being receivable into, so as to be in a point-contact with, a respective corresponding one of the plurality of accommodating grooves.