A garden tool power system comprises a motor, a reducer and a transmission shaft. The motor transmits the power to the transmission shaft through the reducer to drive wheels on the transmission shaft. The reducer comprises a pinion connected to an output end of the motor and a gear engaged with the pinion. The transmission shaft includes left and right shafts connected with each other through a connecting shaft. The gear mounted on the connecting shaft has at least two guiding rods transversely located thereon and two centrifugal blocks located between the guiding rods. Each guiding rod has a spring surrounded therearound and each spring located between two centrifugal blocks has two opposite ends respectively abutted against the corresponding portions of the centrifugal blocks. A fixing sleeve provided on the periphery of the centrifugal blocks is mounted on the transmission shaft and has buckle structures matching with the centrifugal blocks.

A pump group for a cooling system of an engine of a vehicle, of the dual type is provided. The pump group includes an impeller mounted on a shaft commandable in rotation by an electric drive and a mechanical drive. The mechanical drive includes a rotating member commandable in rotation by mechanical movement devices in the vehicle, a rotary drum operatively connected to the shaft, a centrifugal clutch device including a central body integrally attached to the rotating member and a plurality of engagement elements movably fixed on the central body suitable to translate in a radial direction with respect to the axis (X-X) to engage the rotary drum.

A pump group for a cooling system of an engine of a vehicle, of the dual type is provided. The pump group includes an impeller mounted on a shaft commandable in rotation by an electric drive and a mechanical drive. The mechanical drive includes a rotating member commandable in rotation by mechanical movement devices in the vehicle, a rotary drum operatively connected to the shaft, a centrifugal clutch device including a central body integrally attached to the rotating member and a plurality of engagement elements movably fixed on the central body suitable to translate in a radial direction with respect to the axis (X-X) to engage the rotary drum.

An overrunning clutch unit may include inner and outer rings that can be rotated relative to each other. Clamping members may transmit a torque between the two rings in one peripheral direction, the clamping members being arranged between the rings. A first bearing device may be configured to support the two rings, wherein the first bearing device is arranged between the rings at a first axial side of the clamping members. A second bearing device may be configured to support the two rings, wherein the second bearing device is arranged at a second, opposing, axial side of the clamping members so that a tilting of the inner ring relative to the outer ring is prevented.

An overrunning clutch unit may include inner and outer rings that can be rotated relative to each other. Clamping members may transmit a torque between the two rings in one peripheral direction, the clamping members being arranged between the rings. A first bearing device may be configured to support the two rings, wherein the first bearing device is arranged between the rings at a first axial side of the clamping members. A second bearing device may be configured to support the two rings, wherein the second bearing device is arranged at a second, opposing, axial side of the clamping members so that a tilting of the inner ring relative to the outer ring is prevented.

A clutch device includes first frictional elements and second frictional elements connectable to the first frictional elements. The clutch device has a hub connected to a first part of the second frictional elements, a movable contact plate connected to a second part of the second frictional elements, a disengaging plate for actuating the contact plate, and a pressure disk. A first bolt extends through the pressure disk and includes a first end attached to the disengaging plate, and a second end attached to the contact plate. A compression spring is positioned between the first end and the pressure disk. A leaf spring is joined to the contact plate and to the hub. A first centrifugal unit is arranged to move the pressure disk in the axial direction against the compression spring to clamp the first and second frictional elements when a first speed of rotation is reached.

An agricultural header includes: a header frame; at least one cutting unit carried by the header frame and including a cutting element and a driveshaft coupled to the cutting element; and a gearbox configured to drive the cutting element. The gearbox includes a gearbox output rotatably coupled to the driveshaft; and a clutch including an intermediate shaft and at least one clutch shoe rotatably coupled to the intermediate shaft and displaceable between a non-engaging position where the at least one clutch shoe does not engage the gearbox output and an engaging position where the at least one clutch shoe engages the gearbox output. The clutch is configured such that the at least one clutch shoe displaces to the engaging position when a rotational speed of the intermediate shaft reaches a threshold value.

An agricultural header includes: a header frame; at least one cutting unit carried by the header frame and including a cutting element and a driveshaft coupled to the cutting element; and a gearbox configured to drive the cutting element. The gearbox includes a gearbox output rotatably coupled to the driveshaft; and a clutch including an intermediate shaft and at least one clutch shoe rotatably coupled to the intermediate shaft and displaceable between a non-engaging position where the at least one clutch shoe does not engage the gearbox output and an engaging position where the at least one clutch shoe engages the gearbox output. The clutch is configured such that the at least one clutch shoe displaces to the engaging position when a rotational speed of the intermediate shaft reaches a threshold value.

A clutch structure includes a clutch input shaft, a clutch output shaft, a weight member, a one-way clutch, and a bearing. The weight member frictionally contacts a cylindrical portion of the clutch output shaft to transmit a rotational power from the clutch input shaft to the clutch output shaft and separates from the cylindrical portion to disconnect the transmission of the rotational power. When the weight member separates from the cylindrical portion and a rotational frequency of the clutch input shaft falls below a rotational frequency of the clutch output shaft, the one-way clutch links an input shaft portion of the clutch input shaft and an output shaft portion of the clutch output shaft. The one-way clutch and the bearing are located between the input shaft portion and the output shaft portion.

A clutch structure includes a clutch input shaft, a clutch output shaft, a weight member, a one-way clutch, and a bearing. The weight member frictionally contacts a cylindrical portion of the clutch output shaft to transmit a rotational power from the clutch input shaft to the clutch output shaft and separates from the cylindrical portion to disconnect the transmission of the rotational power. When the weight member separates from the cylindrical portion and a rotational frequency of the clutch input shaft falls below a rotational frequency of the clutch output shaft, the one-way clutch links an input shaft portion of the clutch input shaft and an output shaft portion of the clutch output shaft. The one-way clutch and the bearing are located between the input shaft portion and the output shaft portion.