PROBLEM TO BE SOLVED: To provide a power working machine that prevents a temperature around an engine from being increased.SOLUTION: The as a power working machine comprises a body 8 having a pump 7 as a fluid pressure feeding device and an engine 6 for driving the same, and a hose. The self-propelled power sprayer 100 also has a throttle part 16 for narrowing the channel for an exhaust gas of the engine 6 toward the downstream side, a terminal part 17 for sending the exhaust gas which has passed through the throttle part 16 to the outside of the body 8, and an inlet port 18 for introducing the air in the vicinity of the engine 6 into the terminal part 17. An exhaust duct 12 is provided for sending the exhaust gas to the outside of the body 8. Owing to the throttle part 16, flow of the exhaust gas is increased at the throttle part 16 outlet so as to lower the pressure of the throttle part 16 outlet by the Venturi effect. The reduced pressure introduces air in the periphery of the engine 6 from the inlet port 18 to the terminal part 17 so as to prevent a temperature around the engine 6 from being increased.COPYRIGHT: (C)2012,JPO&INPIT【課題】エンジン周辺の高温化を抑制することが可能な動力作業機を提供する。【解決手段】流体圧送装置であるポンプ7及びこれを駆動するエンジン6を有する本体8と、ホースと、を備えた動力作業機である自走式動力噴霧機100に、下流へ向かうに従いエンジン6の排ガスの流路を狭くする絞り部16と、絞り部16を通過した排ガスを本体8の外側へ送り出す終端部17と、エンジン6の周辺の空気を終端部17内に導入するための吸気口18と、を有し、排ガスを本体8の外側に送り出す排気ダクト12を設ける。絞り部16により、絞り部16出口での排ガスの流れを高速化し、ベンチュリー効果で絞り部16出口の圧力を低下させ、この圧力低下により、エンジン6周辺の空気を吸気口18から終端部17内に導入し、エンジン6周辺の高温化を抑制する。【選択図】図2
