There are provided: a travel circuit HC1 that is formed through a closed circuit connection of a variable displacement hydraulic pump 2 driven by an engine 1 and a variable displacement hydraulic motor 3; a work circuit HC2 that includes a work hydraulic pump 4 that is driven by the engine 1 and a work hydraulic actuator 114, 115 that operates by pressure oil from the work hydraulic pump 4; a relief valve 14 that relieves high pressure oil of the travel circuit HC1; a rotation speed control unit 10, 18 that controls the engine rotation speed in correspondence to an operation amount of an accelerator pedal 9; a state detection unit 21, 22 that detects a vehicle state of high load travel and high load work; and a speed limitation unit 10 that reduces an upper limit of engine rotation speed when the vehicle state of high load travel and high load work is detected by the state detection unit 21, 22.

An actuator includes a power source (10), a cam member (15) driven by power from the power source (10), a following member (19) moving in connection with a motion of the cam member (15), an accommodation chamber (20a) accommodating an actuating medium, and a punch cylinder (14) outputting the power transmitted to the actuating medium by the following member (19).

An electro-hydraulic device with an electronic control and regulation system of a hydraulic actuator (21) for deforming fastening elements, comprising: a covering and protecting casing (3); at least a supply chamber (4), contained in the casing (3), for receiving an incompressible fluid and comprising at least an opening (41) for hydraulic communication thereof with at least a respective receiving chamber, comprised in the hydraulic actuator (21); at least a presser element (5), contained in the casing (3), operated by kinematic means (6) for inducing a pressure change to which the incompressible fluid is subjected; the kinematic means (6) being electro-mechanical and being destined to produce a determined change in the mechanical force to which the presser element (5) is subjected, according to predetermined parameters, such that a specific variation of the pressure to which the incompressible fluid results, such as to obtain a regulation of the functioning of the hydraulic actuator (21).

The device comprises a first rocker plate (1) connected to the gear lever (2), a second rocker plate (5) connected mechanically to selector means (9) in the gear unit (8), and two sets (14,17) of three hydraulic transducers each of which comprises a mobile plunger (15) arranged to generate, by virtue of its movement, a corresponding movement of a hydraulic fluid; the plungers of the transducers of each set are disposed at the vertices of a triangle and rest on a corresponding rocker plate, three pipes (18) being provided, each of which hydraulically connects one transducer of a set to the corresponding transducer of the other set in such a manner that, in any instant, a variation in the attitude of the first rocker plate determines a corresponding variation in the attitude of the second.

Selon l'invention, ce dispositif comporte un moteur électrique (M) actionnant un maître-vérin hydraulique (MV) qui, à son tour actionne une pluralité de vérins hydrauliques esclaves (VEI à VEq), liés auxdits organes mobiles.

@ Device for the transmission of mechanical work to a receiver apparatus (19) comprising a hose (2) wound helicoidally around a cylindrical support (3), to which there is also fixed the central turn of the hose (2) filled with a core (10) having a cross section greater than that of the central turn itself. Over the hose (2) in its outermost part there is arranged a flexible continuous element (7, 8, 9) connected at its two ends to two flanges (4, 5) coaxial to the support (3). The hose (2) is filled with a liquid. The rotation of the support (3) in a determined direction relative to the two flanges (4, 5) causes the compression of the turns (30,31) in one of the two tracts into which the hose (2) is subdivided with a direct expelling of the liquid into the receiver apparatus (19) for transforming the thrust of the liquid into a further movement.

A fluid power transmission system comprises a fluid power transmitting unit (12) having a mechanical power input provided by movement of a piston (15) relative to a body portion (14) of the transmitting unit (12) and a fluid power receiving unit (13) having a mechanical power output provided by movement of a piston (15) relative to a body portion (14) of the receiving unit (13). The piston (15) divides a space within the body portion (14) of each unit (12, 13) into first (16) and second (17) chambers. The first chambers (16) of the units (12, 13) are interconnected by a liquid and the second chambers (17) of the units (12, 13) are interconnected by a gas.

Means are disclosed which compensate for changes in the volume of the liquid interconnection due to temperature changes so that a mechanical output from the receiving unit (13) is not affected by such volume changes.