Abstract:
The present concept is a combination mobile boom truck and tower crane which includes a boom portion which includes a boom mounted to a truck portion, the boom portion is moveable between a collapsed position and a boom truck position by extending a boom ram, thereby making the combination crane usable as a boom truck. The combination crane additionally includes a tower portion mounted to the truck portion which is moveable between a collapsed position and a tower crane position. In the collapsed position, the boom portion and tower portion are mounted to the truck portion for transport to and from a jobsite.

Description:
[0001]    This application claims priority from previously filed U.S. provisional patent application No. 61/733,944 filed Dec. 6, 2012 by Charles Pembleton under the title COMBINATION MOBILE BOOM TRUCK &amp; TOWER CRANE. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present concept relates to cranes in general and more particularly relates to mobile boom trucks and tower cranes and more particularly relates to a combination mobile boom truck and tower crane. 
       BACKGROUND OF THE INVENTION 
       [0003]    Known mobile cranes are generally of the type having a mobile platform for example the chassis of a carrier vehicle and are either a dedicated boom truck which includes a pivoting boom and/or jib having telescoping sections which are mounted onto a mobile carrier such as a flatbed truck. 
         [0004]    There are also known mobile tower cranes which are described more particularly in patents filed by Donald E. Wellman in U.S. Pat. Nos. 3,934,729, 3,938,670 and 3,939,988 all under the title Tower Crane by Donald E. Wellman. These tower cranes are mounted onto a chassis of a carrier vehicle and are erected for use as a traditional tower crane. 
         [0005]    Lifting requirements particularly in urban environments in some instances requires the use of a boom truck for lifting and in other instances requires the use of a tower crane for accomplishing the lifting due to the close proximity of buildings and the ability to position the crane in only certain locations. 
         [0006]    There is a need for a combination mobile boom truck and a tower crane which can easily operate as both a traditional boom truck and/or if necessary can be easily erected into the configuration of a tower crane and operated as a tower crane. 
         [0007]    The advantages of the herein described combination mobile boom truck and tower crane will become known to the reader as it is described below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The present concept will now be described by way of example only with reference to the following drawings in which: 
           [0009]      FIG. 1  is a schematic side elevational view of the combination mobile boom truck and tower crane shown in a collapsed position. 
           [0010]      FIG. 2  is a schematic side elevational view of the combination mobile boom truck and tower crane shown in the boom truck operating position. 
           [0011]      FIG. 3  is a schematic side elevational view of the combination mobile boom truck and tower crane shown in a partially erected position. 
           [0012]      FIG. 4  is a schematic side elevational view of the combination mobile boom truck and tower crane in the erected tower crane position. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0013]    The present invention a combination mobile boom truck and tower crane is shown generally as mobile crane  100  which includes the following major components namely a truck portion  194  including a truck  102 , boom portion  190  including boom  104 , and a tower portion  192  including a tower  106 . Truck portion  194  may be any type of mobile platform for use with mobile cranes including but limited to the truck configuration shown in the figures. It may include a tractor section  183  for motorizing the truck portion  194  thereby providing motive power for transporting the combination crane  100  to and from job sites. 
         [0014]    Mobile crane  100  is shown in a collapsed position  101  in  FIG. 1  which is the position in which the combination mobile boom truck and tower crane would be moved from one location to the other down roadways. 
         [0015]    The combination mobile boom truck and tower crane which is depicted as combination crane  100  in both  FIGS. 1 &amp; 2  can be used as a traditional boom truck and is shown in a boom truck position  103  in  FIG. 2  for example. 
         [0016]    The major components in order to operate the combination mobile boom truck and tower crane as a boom truck are the boom portion  190  which includes boom  104  main section  111 , which can be extended with telescoping section  110  and telescoping section  112 . A winch  122  controls the cable  114  which moves across pulleys  116  and terminates at a hook  118  and includes a ballast  120 . 
         [0017]    Boom  104  further includes lower end  181  a boom ram  124  which is used to move boom portion  190  into the boom truck position  103  and also select the angle of the boom  104  relative to horizontal. The tower  106  is mounted horizontally in the collapsed position  101  for transporting between job sites. The cab  126  is mounted on an upper side  231  of tower  106  in the collapsed position and is also supported by support frame  130  when the combination crane  100  is in the collapsed position  101  and boom truck position  103 . 
         [0018]    The operator of boom truck  105  as shown in  FIG. 2  for example would enter cab  126  in order to control boom  104  and operate boom truck  105  in the boom truck position  103 . 
         [0019]    Cab  126  is supported by a cab base  128  which is further supported by support frame  130 . 
         [0020]    Tower  106  which is shown in a horizontal position laying down flat upon platform  134  of truck frame  132  ready for deployment. 
         [0021]    Truck  102  further includes stabilizing outriggers  136  having outrigger pads  138  as well as stabilizing feet  208  located at strategic positions around truck  102 . 
       In Use—Boom Truck 
       [0022]    Combination crane  100  as operated as a boom truck  105  shown in the boom truck position  103  in  FIG. 2  requires little setup. The operator simply climbs into cab  126  to control boom ram  124  and is able to raise and lower the main section  111  of boom  104  and also pivot boom  104  around the base  128  of cab  126  thereby being able to position the hook  118  into the desired location. The operator can also deploy outriggers  136  and stabilization feet  208  as required. 
         [0023]    The operator can extend boom  104  by raising out telescoping sections  110  and  112  as required and can lift and lower a load by either winching in the cable  114  with winch  122  and/or by raising and lowering boom  104  with boom ram  124 . 
         [0024]    The reader will note that a minimal amount of set-up time is required in order to put into operation combination crane  100  as a boom truck  105  and to be able to put it into boom truck position  103 . 
       Tower Crane 
       [0025]    In order to operate the combination mobile boom truck and tower crane as a tower crane  203  the tower portion  192  must be erected from the collapsed position  101  shown in  FIG. 1  to the tower crane position  200  shown in  FIG. 4 . In order to accomplish this a combination of hydraulic cylinder  206  and a tower ram  250  which is hidden from view in the drawings is used to slideably move tower  106  into the partially erected position  202  as shown in  FIG. 3 . Tower  106  partially rests on support frame  130  as the tower  106  is being raised from the horizontal position to the vertical position. 
         [0026]    Cab is approximately always positioned at the lower end  181  of boom  104 . Cab  126  pivots from resting on top of upper side  231  of tower  106  such that cab base  128  comes to rest on the top portion  280  of the upper portion  214  of tower  106  when tower  106  is in the vertical position  270 . Cab  126  is moved into position using cab cylinder  230  and cab cylinder  232 . Hydraulic cylinder  206  is supported by a back stay  242  as well as a cross member  240  which is connected to platform  134 . 
         [0027]    Hydraulic cylinder  206  as well as tower ram  250  and support frame  130  all work together in order to move and support tower  106  from the horizontal position  272  as shown in  FIG. 1  to the tower crane position  200  shown in  FIG. 4  in which the tower is standing vertically upright. 
         [0028]    Tower  106  includes a lower portion  210  terminating at a tower base  212  and a telescoping upper portion  214  terminating at top portion  280 . 
         [0029]    The drawings depict a two section tower  106  when in fact tower  106  may have two, three or more sections depending upon the vertical elevation that is required. 
         [0030]    The reader will note that cab  126  is now located on the top of portion  280  of tower  106 . This enables the operator to have an excellent view downwardly when operating combination crane  100  as a tower crane  203 . 
       In Use—Tower Crane 
       [0031]    When operating combination crane  100  as a tower crane  203  the reader will note that the tower is easily and quickly erected from a horizontal position  272  shown in  FIG. 1  to a vertical position  270  shown in  FIG. 4 . One or more tower portions can be telescopically raised and as depicted in the diagrams in this case a lower portion  210  and an upper portion  214  are used in order to raise tower  106 . On the top of the upper portion  214  namely top portion  280  cab  126  is mounted upon cab base  128 . 
         [0032]    The operator from cab  126  on top of tower  106  can operate the boom by raising and lowering the boom using ram  124  and/or can pivotly rotate the boom  104  about cab base  128 . Additionally the operator can extend boom  104  using telescoping sections  110  and  112  and can pay out cable  114  using winch  122  therefore positioning hook  118  in the desired location. 
         [0033]    The reader will note that the advantage of combination crane  100  is that first of all the operator is sitting on the top of the tower  106  when the crane is in the tower crane position  200 . This provides the operator with an excellent view downwardly such that he can accurately position the hook  118  onto the load that is being lifted. 
         [0034]    The major advantages of the present concept namely combination crane  100  is that it can be easily moved into position at a job site and can be operated either as a boom truck wherein almost no setup time is required other than the deployment of the boom and perhaps outriggers  136 . In the event it is not possible to carry out the lift using a simple boom truck  105  in the boom truck position  103  due to being “boom bound” meaning it is not possible to reach the desired location with the load using a simple boom then it is possible to erect the tower  106  from the horizontal position  272  into the tower crane position  200  and operate the combination crane  100  as a tower crane  203  shown in  FIG. 4  thereby being able to place the combination crane in a position much closer to a building for example thereby avoiding being boom bound. 
         [0035]    It should be apparent to persons skilled in the arts that various modifications and adaptation of this structure described above are possible without departure from the spirit of the invention the scope of which defined in the appended claim.