| 摘要 |
PROBLEM TO BE SOLVED: To simply provide the breathing function of air without special processing tools, by forming a vent groove vertically pierceing a cylindrical screw connected to the upper opening of a case. SOLUTION: When this device is used for a transmission in which a lubricant oil is charged, a cylindrical body 2 is fixed to an opening 1a provided at the upper part of the transmission case 1 by welding or the like and the female screw 5 of a cap 4 is fitted to the male screw 3 provided on the outer periphery of the cylindrical body 2. In this time, a vent groove 7 vertically piercing the screw thread is provided at the male screw 3 of the cylindrical body 2 to enable air to flow to and from the outside through the vent groove 7. In this way, a breathing function can be obtained by a simple processing and a preventing effect against penetration of rainwater can be obtained. |
