Abstract: A simulation method and a simulation system for a construction crane are disclosed. The simulation system includes an input device, a processing device, and a display device. The input device is used for inputting an instruction. Furthermore, the processing device includes a computation unit, a collision detection unit, a storage unit, and a graphic unit. The computation unit is used for computing the position and the direction of each part of the construction crane and the suspension parts. The collision detection model is used for detecting whether each part of the construction crane and the suspension parts will be in collision. Besides, the data obtained from the simulation method performed in the simulation system is saved in the storage unit. The graphic unit displays the 3D dynamics images of the construction crane and the suspension parts on the display device, corresponding to the data obtained from the computation unit.

Abstract: A logging system including a yarder, a skyline, a towline, a carriage riding on the skyline, and a grapple depending from the carriage for grabbing logs and carrying them back to a landing. The carriage and grapple are moved along the skyline for positioning the grapple above a log(s). A remote control device for controlling the slackening and tightening of the skyline and towline, as well as the turning and opening and closing of the grapple. The towline is attached to the grapple, so that when the operator signals the tightening of the towline, the grapple closes around the log.

Abstract: A self-driven transporting unit with a magnetic detector which is propelled along a cable by a drive wheel having spokes arranged in two rows forming a V-shape. The cable is magnetized and mounted in a fixed manner. The spoke arrangement enables the drive wheel to engage with the cable. A programmable electronic control system permits pre-selection of the distance to be covered by the transporting unit and the drop height to which the load is lowered away from the self-driven transporting unit.

Abstract: A novel log-hauling carriage which features a band brake assembly for controlling rotation of a drum in the carriage. The carriage includes a rotatably mounted drum containing three sections on which are wound the main and slackpulling lines, and a drop line which is utilized in raising and dropping the logs. The band brake assembly includes a unique crank and lever system for actuating the brake band, whereby the brake band tightly grips the brake drum surface of the brake assembly, thus to prevent drum rotation, with the slackpulling line loose. The brake assembly is controllably released with tensing of the slackpulling line, differing degrees of tensing producing differing degrees of release of the brake assembly.

Abstract: A remote controlled slack pulling log skidding carriage is provided for feeding a slack drag line toward a log to be skidded. A drive sheave rotatably mounted in the carriage is operated by a hydraulic motor. The fluid to operate the hydraulic motor is stored in one or more accumulators, and a radio controlled valve starts and stops the flow of fluid to the motor. A mechanically operated hydraulic pump also is provided to recharge the accumulators during a skidding operation.

Abstract: A running gear is guided by a carrying rope and movable along the same. A crane housing is connected to said running gear. A pullback rope is secured to the crane housing and operable to pull said crane housing along said carrying rope. A lifting rope pulley formed with a peripheral groove is mounted on a shaft which is mounted in said crane housing. A lifting rope trained around said lifting rope pulley in said groove is adapted to be paid out from said lifting rope pulley by a rotation of the latter in a predetermined sense. A storage drum is mounted on said shaft and non-rotatably connected to said lifting rope pulley. A payout rope is wound on said storage drum and operable to be unwound from said storage drum so as to rotate the same in said predetermined sense. At least one pressure roller is associated with said lifting rope in said groove. Pressure-applying means are provided for forcing said pressure roller against said lifting rope in said groove.