Mobile work machine having support booms

#This application is the National Stage of PCT/EP2009/062168 filed on Sep. 21, 2008, which claims priority under 35U. S. C. §119 of German Application No. 10 2008 055 625.4 filed on Nov. 3, 2008, the disclosure of which is incorporated by reference. The international application under PCT article 21 (2) was not published in English.

#The invention relates to a mobile work machine having a chassis and having two front and two rear support booms, whereby the support booms are mounted, with a bearing-side end, on a swivel joint or slider joint fixed in place on the chassis, carry a telescoping support leg that can be supported on the subsurface at their free end, and can be moved out from a travel position, close to the chassis, into a support position, away from the chassis, by being pivoted, changing the basic angle between support boom and chassis, and/or by being telescoped, changing the length of its support boom between the bearing-side end and the free end.

#Mobile work machines of this type are mobile concrete pumps, for example, which have a concrete distributor that serves as a carrier for a feed line, which distributor is articulated, with its first mast arm, onto a rotating head that can be rotated about a vertical axis of the chassis, by means of controlling a rotary drive, and the mast arms of which distributor can be pivoted about horizontal bending axes, relative to the rotating head and relative to an adjacent mast arm, in each instance, by means of controlling related bending drives. Mobile cranes or mobile extension ladders are other possible applications.

#In the following, the invention will be explained in greater detail using an exemplary embodiment shown schematically in the drawing. This shows:

#FIG. 1a a side view of a mobile concrete pump with support booms in the travel position;

#FIG. 1b a top view of the mobile concrete pump according to FIG. 1, with support booms in various support positions;

#The mobile concrete pump shown in FIGS. 1a and b essentially consists of a multi-axle chassis 10 having two front axles 11 and three rear axles 12, having a driver's cab 13, a concrete distributor mast 15 mounted on a rotary mechanism 14, close to the front axle, to rotate about a vertical axle, having a pump arrangement 16 mounted on the chassis 10 at a distance from the rotary mechanism 14, as well as having a support construction 18 for the chassis 10. The support construction 18 has a support frame 19 fixed in place on the chassis, and comprises two front support booms 20 and two rear support booms 22, which are retracted and oriented parallel to the longitudinal vehicle axis 24 in the transport position, and project beyond the chassis 10 in the support position, at a slant toward the front or toward the rear, respectively.

#The front support booms 20 can be pivoted about their vertical pivot axles 32, and the rear support booms 22 can be pivoted about their vertical pivot axles 34, between a travel position and a support position, under the effect of an extension cylinder 36, in each instance. Furthermore, all the support booms 20, 22 have a telescoping support leg 26, 28 at their free end, with which they can be supported on a subsurface 30, raising the chassis 10.

#The front support booms 20 are configured as telescope booms. They comprise, in each instance, an extension box 38 that can be pivoted relative to the chassis about the vertical pivot axle 32, and a telescope part 40 that consists of three telescope segments 40′, 40″, 40′″. A hydrocylinder that can telescope multiple times, and is not shown in the drawing, extends through the extension box 38 and the telescope part 40. As can be seen in FIG. 1b, the support booms can optionally be supported on the subsurface with their support legs, depending on the space requirements at the construction site, with the formation of different extension configurations, in an inner support position, a support position close to the chassis, or an outer support position, away from the chassis. A particular feature of the present invention consists in that all the intermediate positions between the inner and the outer support position are also possible. The latter is made possible in that a measurement arrangement is provided, with which the position of the support leg 26 in a chassis-fixed coordinate system can be automatically determined.