| 摘要 |
PROBLEM TO BE SOLVED: To provide an air hoist in which malfunction of an overload protection device is prevented.SOLUTION: An air hoist equipped with an air motor 8 which uses air from an air supply source as power includes an overload protection device 10 having: a sensitive valve 20 to which first air supplied from the air motor 8 and second air discharged from the air motor 8 are input, and which senses that a pressure difference between said first air and second air exceeds a predetermined value; an air input control valve 15 for inputting first air into the sensitive valve 20 subsequently to second air; and an air supply stop valve 21 which stops supply of first air to the air motor 8 when the sensitive valve 20 senses that a pressure difference between said first air and second air exceeds the predetermined value.SELECTED DRAWING: Figure 4 |
