摩擦式转速表的英文

• air frictionn tachometer
• air-braking tachomerer
• friction tachomerer

• 摩擦:    rub; chafe
• 式:    type; style
• 转速表:    tachograph; tach; tachometer ...
• 空气摩擦式转速表:    air friction tachometer
• 摩擦式转速计:    air braking tachometer; friction tachometer