Breather structure of actuator

1. An electric actuator, comprising:

a motor and a speed reduction mechanism in a housing;

a recessed groove positioned on an outer surface of the housing;

a breathing hole which is positioned on one side of a bottom surface of the recessed groove and passes through the housing in a first direction;

a filter fixed to the housing and covering the breathing hole from an inside of the housing;

a lid body is fixed to the housing, the lid body partially covering a region of the recessed groove and an entirety of the breathing hole from an outside of the housing when viewed from the first direction;

a breather opening portion positioned at a portion of the recessed groove exposed from the lid body; and

a protrusion portion which protrudes from the bottom surface of the recessed groove to a side of the lid body, the lid body covering an upper end of the protrusion portion when viewed from the first direction; wherein

a portion of the protrusion portion is positioned between the breather opening portion and the breathing hole in a second direction that is perpendicular to the first direction;

the protrusion portion is defined by an arcuate wall portion extending along a circumference of the breathing hole, and including a through portion passing though the wall portion in the second direction; and

a total height of the wall portion in the first direction is equal to a total depth of the recessed groove in the first direction.

2. The actuator according to claim 1 ,

wherein the wall portion surrounds equal to or more than half of the circumference of the breathing hole.

3. The actuator according to claim 1 ,

wherein the lid body is a connection bracket of the actuator.

4. The actuator according to claim 1 , wherein

the housing includes a housing main body that holds the speed reduction mechanism and a speed reduction mechanism cover, and

the lid body is the speed reduction mechanism cover of the actuator.