Abstract: The present invention provides an overload-preventing device for a winch, by which even an overload is caused to descend. The overload-preventing device includes an accommodation hole that is formed in a rotation drive member and is open in the contact plane with a pressing drive member and accommodates a movable piece pressing member and a movable piece. The movable piece is pressed to the side of the pressing drive member by the movable piece pressing member. An engagement groove having a depth in which approx. half of the movable piece can be driven is formed at a part of the contact plane of the pressing drive member. The unwinding side of the engagement groove is formed at the fitting plane while the winding-up side thereof is formed on the inclined surface.

Abstract: A lever hoist with an overload preventing device comprises a pressing member for rotatably pressing a pressed member via a reverse rotation preventing ring and a pair of friction members, and a rotation drive member capable of transmitting rotating force of a chain wheel to the pressing member and movable in an axial direction. The rotation drive member is urged toward the pressing member by a disk spring. Locking teeth are formed at surfaces facing each other, of the pressing member and the rotation drive member, respectively. Respective pressed surfaces during a hoisting-down operation, of the locking teeth are sharply inclined, while respective pressed surfaces during a hoisting-up operation are moderately inclined. A rotation limiting member is interposed between the rotation drive member and the disk spring. Even if the rotation drive member is rotated in an overload state, the rotating force of the rotation drive member cannot be transmitted to the disk spring and a nut.

Abstract: A lever hoist with an overload preventing device comprises a pressing member for rotatably pressing a pressed member via a reverse rotation preventing ring and a pair of friction members, and a rotation drive member capable of transmitting rotating force of a chain wheel to the pressing member and movable in an axial direction. The rotation drive member is urged toward the pressing member by a disk spring. Locking teeth are formed at surfaces facing each other, of the pressing member and the rotation drive member, respectively. Respective pressed surfaces during a hoisting-down operation, of the locking teeth are sharply inclined, while respective pressed surfaces during a hoisting-up operation are moderately inclined. A rotation limiting member is interposed between the rotation drive member and the disk spring. Even if the rotation drive member is rotated in an overload state, the rotating force of the rotation drive member cannot be transmitted to the disk spring and a nut.

Abstract: The present invention provides an overload-preventing device for a winch, by which even an overload is caused to descend. The overload-preventing device includes an accommodation hole that is formed in a rotation drive member and is open in the contact plane with a pressing drive member and accommodates a movable piece pressing member and a movable piece. The movable piece is pressed to the side of the pressing drive member by the movable piece pressing member. An engagement groove having a depth in which approx. half of the movable piece can be driven is formed at a part of the contact plane of the pressing drive member. The unwinding side of the engagement groove is formed at the fitting plane while the winding-up side thereof is formed on the inclined surface.

Abstract: The object is to provide a chain hoist with an overload prevent device, ensuring an easy and secure adjustment of load limit numerical values. It comprises a pressing drive member 8 for pressing and rotating a pressure receive member 7 by way of a backstop wheel 11 and friction members 9 and 10, and an axially displaceable, rotary drive member 14 adapted to transmit a rotational force of a hand chain wheel 15 to the pressing drive member. The rotary drive member is urged toward the pressing drive member by a belleville spring 24. The pressing drive member and the rotary drive member have lock teeth 80 and 140 that are formed on their respective confronting faces. The lock teeth 80 and 140 include steeply sloped wind-down press faces 80a and 140a, respectively, and gently sloped wind-up press faces 80b and 140b, respectively.

Abstract: A lever-type hoist comprising a pressure receiving member 6, a press drive member 7 adapted to press-drive the pressure receiving member 6 through friction members 8, 9 and a reverse rotation stop ring 10, and a coil spring 13 interposed between the pressure receiving member and press-drive member, the base engaging portion 13b of coil spring 13 being engaged by an engaging groove 6d of pressure receiving member and the tip engaging portion of coil spring 13 being engaged by an engaging surface 7k of press-drive member, with an inclined surface 7h formed in the wind-up side of the engaging surface 7k.