Abstract: A method and an arrangement for dampening vibration in a mast structure of a mast truck where the critical characteristics of the mast structure and/or of the vibration are measured, computed, measured and computed or at least some of the characteristics are fed to the computing system in advance, the lowest natural frequency (?n) of the mast structure and/or the phase of the vibration is computed from the collected data or determined directly from the mast structure, the order for movement is obtained from driver or master system, the critical characteristics are fed to the computing system, the movement guidance to the speed controller is generated from above mentioned characteristics of the vibration, the order for movement is divided at least two parts (impulses I), and the actuator is controlled with speed controller for moving the truck or load in the truck according to the order for movement.

Abstract: The invention relates to the mast-hydraulic cylinder construction (4, 5) of a two or multiple-stage forklift mast. The substantially vertical beams (4, 5) and cylinder liners (6) of the solid mast structure form an integrated structure (4, 5), in which the cylinder liners (6) consist of ducts integrated within the beams (4, 5), with the mass centre of the cross-section of the integrated structures being at the centre of the cylinder liner (6) or in its immediate vicinity so that the integrated structure (4, 5) can be manufactured by heat extrusion or cold drawing, and in that the integrated structure (4, 5) comprises a first protrusion (14), whose surface is a bearing surface (17) for a roller bearing (16), and a second protrusion (15) for providing a mass centre at the centre of the cylinder liner (6), and a support surface (18, 19) substantially transverse to the direction of movement of the forklift. The invention also relates to a method for producing an integrated structure (4, 5).

Abstract: The invention relates to an assembly formed by the hoisting cradle (4) and the fork cradle (2) of a forklift truck (1), in which the fork cradle (2) consists of two vertical beams (11, 12) and two horizontal beams (9, 10), the beams (9, 10, 11, 12) forming a substantially rectangular construction, to which hoisting means (3) are attached, the hoisting cradle (4) consisting of two substantially vertical beams (7, 8), one substantially transverse beam (5) and at least one substantially transverse hydraulic cylinder (6), the lower surface (14) of the upper horizontal beam (9) of the fork cradle (2) matching the curved outer surface (13) of the hydraulic cylinder (6), with bearings provided between the surfaces (13, 14). The invention also relates to a corresponding method for transverse shifting of a, fork cradle.

Abstract: A two- or multi-stage mast-hydraulic cylinder construction (4, 5) for a truck mast, and method for manufacturing the intergrated structer (4, 5), are discloused.

Abstract: The invention relates to a two- or multi-stage mast-hydraulic cylinder construction (4, 5) for a truck mast. The fixed mast assembly has its substantially vertical beams (4, 5) and its cylinder liners (29) provide an integrated structure (4, 5), wherein the cylinder liners (29) are constituted by channels integrated inside the beams (4, 5), said integrated structures having their centre of mass at the centre of the cylinder liner (29) or in the immediate vicinity thereof, that the integrated structure (4, 5) is capable of being manufactured by hot extrusion or cold drawing, and that the integrated structure (4, 5) is provided with one flange (13), one side of which comprises a bearing surface (16) and the opposite side comprises a support surface (17), said surfaces (16, 17) lying in a plane transverse to the operating direction of a truck, and with at least one second flange (19) for locating the centre of mass at the centre of the cylinder liner (29) or in the immediate vicinity thereof.