A control unit has as agitation mode in which a command is executed for a first switching valve so that the oil supply/discharge direction is switched so as to supply oil to a first oil supply/discharge port located at a low position and discharge oil from a second oil supply/discharge port located at a high position, whereby oil in an oil bath is agitated via a circulation pump from a low position to a high position is the oil bath; and a filter mode in which, after the agitation mode is executed, a command is executed for the first switching valve so that the oil supply/discharge direction is switched so as to discharge oil from the first oil supply/discharge port located at a low position and supply oil to the second oil supply/discharge port located in a high position, whereby impurities in the oil sent to a filter mechanism are filtered.

A joint shaft structure includes: a base member; an output shaft member supported on one side of the base member so as to be rotatable; and a strain wave gear reducer rotating the shaft member relative to the base member by transmitting rotation of a motor to the shaft member while reducing the speed of the rotation. The reducer includes: a wave generator fixed to a shaft rotated by a driving force from the motor; a flexspline having, at one end, an elastic part which includes a plurality of external teeth and inside which the generator is fitted; and a ring gear disposed on a radially outer side of the flexspline and fixed to the shaft member, and having internal teeth meshing with the external teeth. The flexspline is fixed to the base member at the other end disposed farther on the base member side than the elastic part.

A ring seal and a robot. The ring seal includes an outer circumferential wall and an annular portion. The outer circumferential wall extends in an axial direction of the ring seal. The annular portion extends from a side of the outer circumferential wall toward an interior of the outer circumferential wall in a radial direction of the ring seal. As viewed in a cross section taken along the radial direction, the annular portion and the outer circumferential wall form an L shape.

A tendon and rigid element assembly that includes a tendon subassembly, including a tendon having a longitudinal end having a mating portion. Also, a rigid element has a mating portion. Further, a first one of the mating portions includes a set of projections and a second one of the mating portions defines a set of indentations that are sized and shaped to accept and retain the projections and wherein the set of projections are secured in the set of indentations, thereby securing the tendon to the rigid element.

A robot is provided which has: a housing including a plurality of joints; a reduction gear placed in the joint, the reduction gear including a lubrication chamber where a gear mechanism for slowing down and transmitting an output of a motor and lubricant is sealed; and an air chamber placed inside the housing, the air chamber communicating with the lubrication chamber.

An average value of differences between command current values acquired at a plurality of timings when the motor is controlled at a rotation speed within a preset fixed range in a preset period and an average value of the command current values in the period is acquired, and the average value of the differences is accumulated in an order of the acquisition. When a difference between an accumulated value of the average values of the differences up to an N1th time and an accumulated value of the average values of the differences up to an Nth time becomes greater than or equal to a preset value, and then become less than the preset value, and then again becomes greater than or equal to the preset value, a notification of an abnormality sign in the robot arm is transmitted.

A robot includes a first member, a second member that is provided so as to be movable around the first member, and a gear device that transmits driving force from one of the first member and the second member to the other. The gear device includes an internal gear, a flexible external gear that has an external tooth portion, which partially meshes with the internal gear, and a body portion, which is linked to the external tooth portion in a direction of a rotation axis, and a wave generator that comes into contact with the external gear and moves a position where the internal gear and the external gear are meshed with each other in a circumferential direction. An exterior surface of the body portion has an oil-repellent portion of which oil repellency is higher than oil repellency of an exterior surface of the external tooth portion.

A robot arm includes a first member, a second member, an actuator, and a speed reducer. The second member is pivotable relative to the first member about a pivot axis. The actuator is configured to pivotally move the second member relative to the first member about the pivot axis. The speed reducer is configured to couple the actuator to the second member to reduce a rotational speed of the second member relative to an output rotational speed of the actuator. The speed reducer includes a grease chamber in which grease is to be provided. The second member including an air chamber in which air is provided, the air chamber being connected to the grease chamber.

A lubricant bath structure includes a casing for storing a liquid lubricant, where: the casing is provided with a supply hole, a discharge hole, a part attachment hole, and a liquid level check hole that penetrate from inside to outside of the casing; the supply hole enables injecting the lubricant into the casing; the discharge hole enables discharging the lubricant in the casing; the part attachment hole is opened/closed by detaching/attaching a mechanism part that is to be detachably attached to an outside surface of the casing; and the liquid level check hole can be arranged at a position coincident with or lower than a lower edge of the part attachment hole, but higher than the discharge hole, and, during the discharge of the lubricant, it is possible to confirm that a liquid level of the lubricant has reached below the lower edge of the part attachment hole.

A finger includes a pair of overhanging portions that project out laterally from a main body portion. Outer peripheral surfaces of the overhanging portions are made up from five surfaces including upper surfaces, side surfaces, lower surfaces, first end surfaces, and second end surfaces. Crowning is applied to the intersections between these surfaces.