US 12,390,900 B2
Work machine
Kentaro Hatakeyama, Ibaraki (JP)
Assigned to KOKI HOLDINGS CO., LTD., Tokyo (JP)
Appl. No. 17/794,881
Filed by KOKI HOLDINGS CO., LTD., Tokyo (JP)
PCT Filed Dec. 25, 2020, PCT No. PCT/JP2020/048840
§ 371(c)(1), (2) Date Jul. 22, 2022,
PCT Pub. No. WO2021/149459, PCT Pub. Date Jul. 29, 2021.
Claims priority of application No. 2020-010369 (JP), filed on Jan. 24, 2020.
Prior Publication US 2023/0055261 A1, Feb. 23, 2023
Int. Cl. B24B 41/04 (2006.01); B24B 23/02 (2006.01); B24B 47/12 (2006.01)
CPC B24B 41/04 (2013.01) [B24B 23/028 (2013.01); B24B 47/12 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A work machine comprising:
a gear housing;
a spindle protruding in a downward direction from the gear housing;
a bearing held by the gear housing and comprising an inner race and an outer race, the bearing rotatably supporting the spindle;
a tip tool attachment portion to which a tip tool is attachable, the tip tool attachment portion being provided at the spindle;
a sealing member positioned below the bearing; and
an annular element restricting the sealing member from moving in the downward direction,
wherein the gear housing comprises a bearing holding portion holding the bearing,
wherein the bearing holding portion comprises:
a cylindrical portion extending in an up-down direction, the cylindrical portion being in contact with an outer circumferential surface of the outer race to support the outer race; and
a first protruding portion positioned below the outer race, the first protruding portion protruding inward in a radial direction of the spindle from the cylindrical portion, the first protruding portion being in contact with a lower surface of the outer race from below to restrict the bearing from moving in the downward direction,
a second protruding portion positioned above the outer race, the second protruding portion protruding inward in the radial direction of the spindle from the cylindrical portion, the second protruding portion being in contact with an upper surface of the outer race from above to restrict the bearing from moving in an upward direction,
wherein the annular element is held either by the spindle or by the gear housing,
wherein the cylindrical portion, the first protruding portion and the second protruding portion are included in the gear housing and are formed as a single member, and
wherein the first protruding portion is positioned further outward in the radial direction than a lower end of an inner circumferential surface of the outer race, and
wherein the second protruding portion is positioned further outward in the radial direction than an upper end of the inner circumferential surface of the outer race.