Dipper door and dipper door trip assembly
A mining machine includes a boom, a handle coupled to the boom, a dipper coupled to the handle, and a dipper door pivotally coupled to the dipper. The mining shovel also includes a dipper door trip assembly including a trip motor coupled to the boom, a trip drum coupled to the handle, a linkage assembly coupled to the dipper door, a first actuation element extending directly from the trip motor to the trip drum, and a second actuation element extending directly from the trip drum to the linkage assembly.
1. A dipper door trip assembly comprising:
a latch bar having an opening sized to receive a latch lever bar, and an insert disposed at least partially within the opening, the insert having a bearing surface sized and shaped to engage a surface of the latch lever bar, wherein the insert includes a pin and a roller that rotates about the pin, wherein the bearing surface is on the roller.
2. The dipper door trip assembly of claim 1 , further comprising the latch lever bar, wherein the latch lever bar includes a recessed portion in contact with the roller.
3. The dipper door trip assembly of claim 1 , wherein the opening is disposed at a first end of the latch bar, and wherein the latch bar includes a separate latch bar insert disposed at an opposite end of the latch bar.
4. The dipper door trip assembly of claim 1 , wherein the bearing surface is curved.
5. The dipper door trip assembly of claim 4 , further comprising the latch lever bar, wherein the latch lever bar includes a curved surface in contact with the curved bearing surface.
6. The dipper door trip assembly of claim 1 , further comprising a lever arm coupled to the latch bar, and a trip drum coupled to the lever arm.
7. The dipper door trip assembly of claim 6 , wherein the opening extends entirely through an upper portion of the latch bar.
8. The dipper door trip assembly of claim 1 , wherein the latch bar includes a recessed flange having an aperture configured to receive a pin.
9. A mining machine comprising:
a dipper; and
the dipper door trip assembly of claim 1 , wherein the latch bar is disposed at least partially within the dipper.
10. The dipper door trip assembly of claim 1 , further comprising the latch lever bar, and a spherical bearing or bushing disposed on the latch lever bar.
11. A dipper door trip assembly comprising:
a latch bar having an opening sized to receive a latch lever bar, and an insert disposed at least partially within the opening, the insert having a curved bearing surface sized and shaped to engage a surface of the latch lever bar, wherein the opening is disposed at a first end of the latch bar, and wherein a separate latch bar insert is fixed to the latch bar at an opposite end of the latch bar.
12. The dipper door trip assembly of claim 11 , further comprising the latch lever bar, and a spherical bearing or bushing disposed on the latch lever bar.
13. The dipper door trip assembly of claim 11 , further comprising the latch lever bar, wherein the latch lever bar includes a curved surface in contact with the curved bearing surface.
14. The dipper door trip assembly of claim 11 , further comprising a lever arm coupled to the latch bar, and a trip drum coupled to the lever arm.
15. A dipper door trip assembly comprising:
a latch lever bar;
a spherical bearing or bushing disposed on the latch lever bar;
a latch bar having an opening sized to receive the latch lever bar; and
an insert disposed at least partially within the opening, the insert having a bearing surface sized and shaped to engage a surface of the latch lever bar.
16. The dipper door trip assembly of claim 15 , wherein the latch lever bar includes a recessed portion in contact with the bearing surface.
17. The dipper door trip assembly of claim 15 , wherein the bearing surface is curved.
18. The dipper door trip assembly of claim 15 , further comprising a lever arm coupled to the latch bar, and a trip drum coupled to the lever arm.
19. A mining machine comprising:
a dipper; and
the dipper door trip assembly of claim 15 , wherein the latch bar is disposed at least partially within the dipper.
20. A dipper door trip assembly comprising:
a latch bar having an opening sized to receive a latch lever bar;
an insert disposed at least partially within the opening, the insert having a bearing surface sized and shaped to engage a surface of the latch lever bar, wherein the opening is disposed at a first end of the latch bar;
a separate latch bar insert is fixed to the latch bar at an opposite end of the latch bar;
a lever arm coupled to the latch bar; and
a trip drum coupled to the lever arm.