A knockdown, portable lift is relatively compact and lightweight for transport and use where there is no existing means for lifting a load between a lower surface and an upper surface or where the existing means cannot be used. Components of the lift are stored in a base portion of the lift and are assembled on site for forming a lift frame extending between the upper and lower surfaces. A platform and drive assembly are supported on the lift frame and are driven together up and down tracks on each side of the lift frame using a rotary drive, such as a hand crank or electric motor, to power the drive assembly. The drive assembly is operable by a person on or off the platform from either the upper or lower surface or traversing stairs over which the platform is moving. The drive assembly incorporates a unique overspeed braking system and a unique clutch arrangement.

A knockdown, portable lift is relatively compact and lightweight for transport and use where there is no existing means for lifting a load between a lower surface and an upper surface or where the existing means cannot be used. Components of the lift are stored in a base portion of the lift and are assembled on site for forming a lift frame extending between the upper and lower surfaces. A platform and drive assembly are supported on the lift frame and are driven together up and down tracks on each side of the lift frame using a rotary drive, such as a hand crank or electric motor, to power the drive assembly. The drive assembly is operable by a person on or off the platform from either the upper or lower surface or traversing stairs over which the platform is moving. The drive assembly incorporates a unique overspeed braking system and a unique clutch arrangement.

A fall protection device including a first housing part, a second housing part, a rotation unit, a safety belt, a spiral spring for coiling the safety belt around the rotation unit and a brake unit for limiting rotation of the rotation unit is disclosed. The first and the second housing parts respectively include a first containing room and a second containing room. The first and the second housing parts conjugate with each other and constitute a housing. The brake unit is positioned in the first containing rooms, while part of the safety belt and the spiral spring are positioned in the second containing rooms. By separately positioning the brake unit and the safety belt in the first and the second rooms, the dust coiled together with the safety belt into the housing will not adhere to the brake unit and its effect on the brake unit's function is prevented.

A fall protection device including a first housing part, a second housing part, a rotation unit, a safety belt, a spiral spring for coiling the safety belt around the rotation unit and a brake unit for limiting rotation of the rotation unit is disclosed. The first and the second housing parts respectively include a first containing room and a second containing room. The first and the second housing parts conjugate with each other and constitute a housing. The brake unit is positioned in the first containing rooms, while part of the safety belt and the spiral spring are positioned in the second containing rooms. By separately positioning the brake unit and the safety belt in the first and the second rooms, the dust coiled together with the safety belt into the housing will not adhere to the brake unit and its effect on the brake unit's function is prevented.

The present invention provides a system and method for providing drive shaft braking for an irrigation machine. According to an exemplary preferred embodiment, the present invention includes a system for providing drive shaft braking during the operation of an irrigation machine where the irrigation machine includes a drive system having a drive motor and a drive shaft. According to a preferred embodiment, the system in accordance with the present invention preferably includes a cam attached to the drive shaft, an extension arm having a first securing point, a securing arm having a second securing point and a spring attached between the first securing point and the second securing point. According to a further preferred embodiment, the system of the present invention preferably further includes a follower mechanism secured to the extension arm, which applies continual frictional pressure to the drive shaft in response to the force applied by the spring to the follower through the extension arm. According to a further preferred embodiment, an exemplary system according to the present invention functions to hold the drive shaft in place when rotational force is not actively applied to the drive shaft by the drive motor.

A fall protection device including a first housing part, a second housing part, a rotation unit, a safety belt, a spiral spring for coiling the safety belt around the rotation unit and a brake unit for limiting rotation of the rotation unit is disclosed. The first and the second housing parts respectively include a first containing room and a second containing room. The first and the second housing parts conjugate with each other and constitute a housing. The brake unit is positioned in the first containing rooms, while part of the safety belt and the spiral spring are positioned in the second containing rooms. By separately positioning the brake unit and the safety belt in the first and the second rooms, the dust coiled together with the safety belt into the housing will not adhere to the brake unit and its effect on the brake unit's function is prevented.

An actuator comprises a housing, a motor, a drive mechanism and a clutch coupled to the drive mechanism. The motor is mounted displaceably relative to the housing. A displacement of the motor relative to the housing is operative to actuate the clutch.

An actuator comprises a housing, a motor, a drive mechanism and a clutch coupled to the drive mechanism. The motor is mounted displaceably relative to the housing. A displacement of the motor relative to the housing is operative to actuate the clutch.

Apparatus to provide motor backdrive resistance are described. An example apparatus described herein includes a brake to engage an output shaft of a motor. The example apparatus also includes a brake release arm operably coupled to the brake. A reaction arm is fixed relative to the brake release arm and operatively coupled to the motor. The reaction arm causes the brake to disengage the output shaft of the motor in response to a reaction torque of the motor.

Apparatus to provide motor backdrive resistance are described. An example apparatus described herein includes a brake to engage an output shaft of a motor. The example apparatus also includes a brake release arm operably coupled to the brake. A reaction arm is fixed relative to the brake release arm and operatively coupled to the motor. The reaction arm causes the brake to disengage the output shaft of the motor in response to a reaction torque of the motor.