Self-pumping hydrodynamic mechanical seal

2:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein modeled lines of the groove walls on both sides of the backward curved grooves (39) are spiral lines.

3:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 2, wherein the spiral lines, which are the modeled lines of the groove walls on both sides of the backward curved grooves (39), have same spiral angles.

4:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 2, wherein the spiral lines, which are the modeled lines of the groove walls on both sides of the backward curved grooves (39), have different spiral angles, wherein the spiral angle of the working face (34) is smaller than the spiral angle of the non-working face (35).

5:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 2, wherein the spiral lines, which are the modeled lines of the groove walls on both sides of the backward curved grooves (39), are tangent with circular holes of the inlets (31).

6:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein the duct (30) is provided on the rotating ring (3), a cross section of a joint portion of the duct (30) and an external round face of the rotating ring (3) is a wedge-shaped opening (38), a rotation direction of the rotating ring (3) is same with a width decreasing direction of the wedge-shaped opening (38).

7:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein the duct (30) is provided on the stationary ring (11).

8:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 7, wherein a loop groove (46) opposite to the inlets (31) of the backward curved grooves (39) is provided on a seal face of the stationary ring (11), the loop groove (46) connects with the seal chamber (1) through the duct (30) on the stationary ring (11).

9:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein the inlets (31) of the backward curved grooves (39) connects with a loop groove (36) on the seal face of the rotating ring (3), the loop groove (36) connects with the seal chamber (1) through the duct (30).

10:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 9, wherein the duct (30) is provided on the stationary ring (11), an outlet of the duct (30) is provided on a seal face of the stationary ring (11) and is opposite to the loop groove (36).

11:

• (canceled)

12:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein each of the backward curved grooves (39) comprises a slope groove (32) and a flat groove (33), wherein the slope groove (32) is provided at a large radius portion of the end face of the rotating ring, the flat slope groove (33) is provided at a small radius portion of the end face.

13:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein the duct provided on the rotating ring (3), and the duct (30) is parallel to the axis of the rotating ring (3).

14:

• The self-pumping hydrodynamic mechanical seal, as recited in claim 1, wherein the duct (30) is an axial-radial-combined duct.