Speed reducer and industrial machine

A speed reducer comprising:

• a case;
• a carrier at least partly located in the case;
• a main bearing located between the case and the carrier;
• and
• a sealing member including:
• a first ring having an annular shape and mounted to one of the case and the carrier;
• a second ring in contact with an annular region of the first ring;
• and
• an elastic ring compressed between the second ring and another of the case and the carrier,
• wherein the sealing member is at least partly located in a same region as the main bearing in a radial direction perpendicular to a rotation axis of the carrier rotating relative to the case,
• wherein the carrier is at least partly located in the case so as to have a gap between the carrier and the case on an outer side of the annular region in the radial direction, and
• wherein the gap includes a portion extending in the radial direction and a portion extending in an axial direction parallel to the rotation axis.

An industrial machine comprising:

• a drive device including a speed reducer,
• wherein the speed reducer includes:
• a case;
• a carrier at least partly located in the case;
• a first main bearing and a second main bearing located between the case and the carrier;
• an external gear located between the first main bearing and the second main bearing in an axial direction parallel to a rotation axis of the case and the carrier relative to each other;
• and
• a sealing member that provides sealing between the case and the carrier, wherein the sealing member includes:
• a first ring having an annular shape and mounted to one of the case and the carrier;
• a second ring in contact with an annular region of the first ring;
• and
• an elastic ring compressed between the second ring and another of the case and the carrier, and
• wherein the sealing member is at least partly located in a same region as the first main bearing and the second main bearing in a radial direction perpendicular to the rotation axis, and
• wherein the carrier is at least partly located in the case so as to have a gap between the carrier and the case on an outer side of the annular region in the radial direction, and wherein the gap includes a portion extending in the radial direction and a portion extending in the axial direction parallel to the rotation axis.