Patent Publication Number: US-6983763-B2

Title: Telescoping boom with moving flexible 180° bend

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application is a national stage of PCT/EP02/02161 filed Feb. 28, 2002 and based upon DE 101 12 086.9 filed Mar. 12, 2001 under the International Convention. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a distributor device for thick matter, especially for concrete. The distributor device comprises a concrete distributing boom carrying a conveying conduit, which has at least two boom arms that can be swiveled about horizontal articulation axes relative to one another or relative to a boom support, of which at least one of the boom arms is telescopically extendable and includes a static telescope part and a telescope part extendable relative to the static part, wherein the conveying conduit is assembled from multiple linked conduit sections, of which a first conduit section is preferably rigidly linked with the stationary member, while a second conduit section is rigidly linked with the extendible telescoping member, and wherein an intermediate piece adaptable to the extension of the telescoping part connects the first and second conduit sections. 
   2. Description of the Related Art 
   Distribution devices of this type are employed mainly for conveyance of concrete, for example for production of concrete decks in high-rises. The conveyance conduit extends along the boom arms and includes articulation connections in the area of the articulation axes and axially parallel thereto. In the area of the telescopic boom arm there is additionally a need for a length adapter for the conveyor conduit. 
   In a distribution device of the above described type it is known (U.S. Pat. No. 4,130,134) to provide a distribution boom for a mobile concrete pump with a telescopic base arm. The length adaptation of the conveyor conduit occurs therein by a scissors system comprised of three articulated conduit segments connected to each other. The conduit segments project sideways far beyond the telescopic boom arms during the telescoping process and represent thereby an impediment to boom movement. Beyond this, strict limitations or boundaries exist for the telescope hub of the thereby described telescope design on the basis of the scissors-like design of the conveyor conduit segment. 
   SUMMARY OF THE INVENTION 
   Beginning therewith, it is the task of the present invention to develop a distribution device for thick matter pumps, which can make possible with simple means a length adaptation of the conveyor conduit on a telescopic boom arm even in the case of a large telescope extension or stroke. 
   For solving this task, the combination of characteristics set forth in Patent claim  1  are proposed. Advantageous embodiments and further developments of the invention can be seen from the dependent claims. 
   The inventive solution is based upon the idea, that the intermediate segment adaptable to the telescope movement of the telescope part is in the form of a flexible hose connected with its ends to a first and a second conduit segment, which includes a 180° bend with constant curvature parallel to the direction of the telescope stroke. A hose of this type can be easily adapted to various telescope strokes or extensions by change of its length. 
   A preferred embodiment of the invention envisions that the flexible hose is partially supportable in a support wall or cradle rigidly connected with a fixed part, wherein the 180° bend projects beyond the support wall and wanders with its wall-side end along the support wall during telescoping. The support wall is preferably provided spaced apart from the fixed part. According to a further advantageous embodiment of the invention the fixed part besides this includes, spaced apart from the support wall, a convex support link or slider for supporting the 180° bend in the retracted condition of the telescope part. For further improvement of the hose guidance during telescoping the telescope part carries in the area of its interfacing with the fixed part an abutment link or slider extending over or about the outlet side end of the hose. 
   In accordance with a further advantageous embodiment of the invention it is envisioned that the first conduit segment includes a parallel part extending out from the bend linkage of the fixed part essentially parallel to the longitudinal extension thereof and a thereto connectable slanted part extending diagonally to the fixed telescope part until in the vicinity of the support wall, to the later of which the hose is connected with its parallel to the support wall oriented inlet. Further, there is proposed in accordance with the invention, that the second conduit segment includes a pipe running from the bend linkage of the telescope part out in essentially parallel to the telescope axis, to which the hose is connected with its outlet side facing in the inlet direction, and preferably via a 180° pipe curvature. 
   It is particularly advantageous when the base arm linked to the boom block rotatable about a vertical axis of the distribution boom is telescopic. 
   A particularly advantageous embodiment of the invention is comprised therein, that the distribution boom is provided upon a vehicle chassis of a mobile concrete pump, wherein the conveyance conduit is connected to the pressure outlet of a conveyor pump provided on the vehicle. 
   According to a further preferred embodiment of the invention it is envisioned that the distribution boom is linked with its telescopic base arm to a boom block rotatable 360° about a vehicle chassis fixed vertical axis and mounted on the vehicle chassis in the vicinity of the driver cabin, and that the separation between the rotation axes and the slanted part of the first guide segment corresponds to at least the distance between the rotation axes and the forward edge of the driver cabin. Thereby the possibility of a collision of the conveyor conduit with the driver cabin during telescoping of the base arm with horizontal pivoted-out distribution boom over the driver cabin is avoided. 
   The fixed part of the telescopic base arm is preferably longer than the subsequent boom arms of the distribution boom. With the inventive means it is possible that the telescopic base arm carries out a large telescopic extension. It has been found particularly advantageous when the telescopic base arm in the extended condition of the telescopic part is 1.6 to 3.5 times as long as the subsequent boom arms. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the following the invention will be described in greater detail on the basis of the figures. There is shown 
       FIG. 1  a side view of a mobile concrete pump with three axle vehicle chassis and distribution boom with telescopic base arm in folded in-transport configuration and unfolded and telescoped working configuration; 
       FIG. 2  a side view of a mobile concrete pump with four axle vehicle chassis and a representation according to  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The mobile concrete pump shown in the figures includes a vehicle chassis  10  with a driver cabin  12 , a thick matter pump  14  in the form of, for example, a two cylinder piston pump, as well as a distribution device  16 , which includes a distribution boom  18  as carrier for a concrete conveyor line  20 . Fluid concrete is conveyed along the concrete conveyance conduit, which is continuously introduced into a supply container  22  during concretizing and conveyed to a concretizing location located distant from the position of the vehicle  10 . 
   The distribution device  16  includes a boom block  26  rotatable about a vehicle chassis-fixed vertical axis  24  by means of a hydraulic rotation drive, and a distribution boom  18  pivotable thereupon, which is adjustable to variable extension and height differences between the vehicle  10  and the concretizing location. The distribution boom  18  is comprised in the illustrated exemplary embodiments of four boom arms connected articulated with each other  30  through  36 , which are pivotable about articulation axes  38  through  44  extending parallel to each other and perpendicular to the rotation axis  24  of the boom block  26 . The base arm  30  linked to the boom block  26  in the area of the articulation axis  38  is, besides this, a telescoping arm comprised of a fixed part  46  and a extendable telescope part  48  aligned therewith. The articulation axes  38  through  44  and the telescope axes  68  are so coordinated relative to each other, that the distribution boom  28  in the case of retracted telescope part  48  and with multiple folding of the boom arms  30  through  36  is collapsible into a space-saving transport configuration upon the vehicle chassis  10 . The distribution boom  18  can be unfolded to extend between the vehicle location and the concretizing location by activation of drive aggregates  50  through  56  in the form of hydraulic cylinders, which are associated with the articulation axes  38  through  44 , as well as a not shown drive aggregate for the telescope part  48 . 
   One special feature of the distribution device  16  shown in  FIGS. 1 and 2  is comprised therein, that the conveyor line  20  in the area of the telescopic boom arm  30  was an assembly of three conveyor segments connected with each other, of which a first conveyor segment  58  is rigidly connected with the fixed part  46  and a second conveyor segment  60  is rigidly connected with the telescope part  48 , while the intermediate segment  62  is adaptable to the telescope movement of the telescope part  48 . The intermediate segment  62  is in the form of a flexible relatively stiff hose, which with its inlet end  64  is connected to the output of the first conveyor segment  62  and with its output end  66  is connected to the input of the second conveyor segment  60 . The hose  62  includes a 180° bend  70  of constant curvature which wanders or moves along during the telescope movement parallel to the telescope axis  68 . In order to maintain a constant 180° curvature during telescoping, the hose  62  is partially supportable by a support wall  74  rigidly connected with the fixed part  46  via strut  72 . The 180° bend wanders with its wall end along the support wall during telescoping and projects with the rest beyond the support wall. On one side of the extendable telescope part  48  there is additionally a fixture  46  extending over or about the output bend  66  of the hose  62 . The hose  62  is there connected with its output end  66  via a 180° pipe curvature  78  to the input of the second conveyor segment  60 . For stabilizing the hose  62  in the end position of the extendable telescope part  48  the fixed part  46  carries spaced apart from the support wall  74  a convex support linkage  80  for supporting the 180° bend  70 . 
   A further particular feature is comprised therein, that the first conveyor segment  58  includes a longitudinal part running from the articulation axis  38  of the fixed part  46  outward and essentially parallel thereto and a thereto connected diagonal part  84 , extending diagonally to the fixed telescopic part  48  until in the vicinity of the support wall  74 , to which the hose  62  with its parallel to the support wall  74  oriented inlet end  64  is connected. By this means it is achieved that a free space  86  remains below the base arm  30 , which makes it possible to rotate the distribution boom with horizontal oriented base arm  30  over the driver cabin  12  without danger of collision. For this purpose the distance between the rotation axes  24  of the boom block  26  and the slanted part  84  corresponds at least to the distance between the rotation axes  24  and the forward edge  88  of the driver cabin  12 . In the embodiments shown in  FIGS. 1 and 2  the fixed part  46  of the telescopic base arm  30  is longer than the subsequent boom arms  32  through  36 . In the extended condition the telescopic base arm upon utilization of the full telescope stroke or length is in the case of  FIG. 1  approximately 1.7 times as long as the subsequent boom arms. In the case of  FIG. 2  the extended base arm is even 2.5 times as long as the subsequent boom arms. 
   The described mobile concrete pumps are particularly suited for movement under ceilings in high rises, wherein the telescopic base arm  30  essentially contributes thereto that the distribution device  16  is adaptable from the location of the vehicle  10  out to a predetermined floor. By the use of a hose  60  with 180° bend  70  a concrete pump builder is provided with a construction principle that is adaptable to any telescope stroke. He need essentially merely select an appropriate hose length. 
   In summary the following can be concluded: The invention concerns a distributor device for thick matter, especially for concrete. The distributor device  16  comprises a concrete distributing boom  18  carrying a conveying conduit  20 , which has at least two boom arms  30  to  36  that can be swiveled about horizontal articulation axes  38  to  44  relative to one another or relative to a boom support  26 . At least one of the boom arms, preferably the base arm  30 , is telescopically movable. In order to be adaptable to the telescoping movements, the conveying conduit is assembled from three interlinked conduit sections in the area of the telescoping boom arm. A first conduit section  58  is rigidly linked with the stationary member  46 , while a second conduit section  60  is rigidly linked with the extensible telescoping member  48 . The device further comprises an intermediate section  62  which is connected with its ends  64 ,  66  to the first and the second conduit section  58 ,  60  and which is configured as a flexible pipe. Said pipe has a 180° arch  70  with constant curvature that travels when the boom arm telescopes.