A rope grab device for a portable power driven system adapted for advancing a rope includes an essentially circular rope grab, wherein the rope grab is adapted to, during operation, engage the rope along at least a section of a circumference of the rope grab. The rope grab device also includes a securing device comprising a leaver portion, a first roller arranged at one end of the leaver portion for guiding an unloaded end of the rope and an anchoring point arranged at the opposite end of the leaver portion adapted for receiving an anchoring force from a load connectable to the portable power driven system. The leaver portion is attached with a hinged connection arranged between the one end and the opposite end to the rope grab device and is adapted to, by means of the first roller, exert a pressure to the rope for forcing the roped towards the rope grab at a portion of the section where the rope, during operation, is engaging the rope grab upon applying the anchoring force on the anchoring point.

A method for an operation of a forestry winch, which has a rope drum driven by a drive motor and on which a rope is wound up, and has a rope ejector roller for the rope driven by an additional drive motor, whereby the rope is guided from the rope drum to the rope ejector roller and is deflected on the rope ejector roller. The drive motor of the rope drum and the additional drive motor of the rope ejector roller are operated so that when the rope is unspooled from the rope drum, and when the rope is wound up onto the rope drum, a minimum rope pre-tension, in particular a constant minimum rope pre-tension, is generated in the segment of the rope between the rope drum and the rope ejector roller.

The present disclosure relates to a portable device for hoisting/lowering/storing a rope from a tall structure, such as a wind turbine. The device is formed of an assembly of a rope storage container and a rope driver reversibly connected thereto. The rope storage container defines a rope storage volume bound between a bottom surface and an outer side wall. The rope driver is reversibly connectable to the container and comprises a rope passage having a dimension matching a diameter of the rope. The passage is formed between a pair of adjacent rollers or between a drive coil and a clamp. The rope is driven (hoisted and stored or provided and lowered) by an electric motor arranged to drive at least one of the rollers or the drive coil.

A winch drum is disclosed. In a first aspect, a first set of teeth are positioned around an outer perimeter of a drum. The first set of teeth taper from a first crown to a first base. A second set of teeth are positioned around the outer perimeter of the drum. The second set of teeth taper from a second crown to a second base. The second set of teeth are offset from the first set of teeth such that a gap between the first bases and the second bases forms a sinusoidal channel for a line to follow the first set of teeth and the second set of teeth becomes a guide for the line so that the line can engage the sinusoidal channel. The line follows the sinusoidal channel and each change of direction along the sinusoidal path causes the line to engage by friction with the first bases and the second bases. In a second aspect, the drum includes a trough that follows a sinusoidal path and wherein the trough is narrower at its bottom than at its top.

The present invention relates to a user interface for a portable power driven system, specifically in relation to an integrated user interface for controlling such an arrangement, and being applicable for example in relation to an ascender/descender arrangement. The invention also relates to a corresponding method and computer program product for operating such a portable power driven system.

Winch with a grip pulley for moving along a lifting strand, in particular a rope or cable, including a frame; a drive pulley with a single groove mounted on said frame; a guide means capable of guiding the lifting strand under tension from the upper region of said frame towards the lower region thereof, the guide means comprising on the lower region side of said frame a guide pulley close to the drive pulley and transferring the taut lifting strand onto the drive pulley; a clamping pulley, close to said guide pulley, exerting pressure on the lifting strand towards said drive pulley and acting on the wrapped end of the lifting strand on said pulley on the free strand side.

The present invention relates to a safety arrangement for a portable power driven system, such as an ascender/descender arrangement, specifically in relation to safety means for minimizing risks with items rotating during the operation of the power driven system.

An ejector for a forestry winch that includes a rotating ejector roller, over which a synthetic rope is guided and deflected, wherein the ejector roller is driven by a drive motor, and at least one rotating pressure roller, by means of which the synthetic roe is pressed against the ejector roller, wherein the driven ejector roller and the at least one rotating pressure roller are coupled in rotation.

An ejector for a forestry winch, the ejector may include a rotating ejector roller by means of which a synthetic rope is guided and deflected, wherein the ejector has at least one rotating pressure roller driven by a drive motor and by means of which the synthetic rope is pressed against the ejector roller.

A tree section lowering assembly is provided. The tree section lowering assembly includes a support member having a first side, an opposing second side, a first end, and an opposing second end. A plurality of rung members extend from the first side of the support member. Each of the plurality of rung members has an outer surface configured to facilitate a frictional, sliding engagement with an interlaced rigging line. A reinforcement member extends from the second side of the support member and is configured to structurally support the support member. An upper line guide extends from a rung member at the located first end of the support member and a lower line guide extends from a different rung member located at the second end of the support member.