Structural beam

Abstract

A fabricated structural beam ( 1 ), including a longitudinally extending top plate having a pair of longitudinally extending opposite edge regions ( 4 ), and a longitudinally extending cylindrical bottom tube ( 6 ) spaced from and extending parallel with the top plate ( 3 ) equidistant from the edge regions ( 4 ) of the top plate ( 3 ). A web plate ( 13 ) of generally V shape in transverse cross section provides a pair of web portions ( 12 ) and a bend portion 14 between the web portions ( 12 ). The bend portion ( 14 ) extends about the bottom tube ( 6 ) so that the bottom tube ( 6 ) nests along the web plate ( 13 ), and the web plate ( 13 ) is connected to the bottom tube ( 6 ) along opposite side regions ( 11 ) thereof. The web portions ( 12 ) extend one from each side of the bottom tube ( 6 ) to the top plate ( 3 ). Each web portion ( 12 ) has a longitudinally extending connection region connected along the top plate ( 3 ) adjacent a respective edge region ( 4 ) of the top plate ( 3 ). The beam ( 1 ) tapers in lateral extent from the top plate ( 3 ) to the bottom tube ( 6 ). A torsion beam crane ( 100 ) incorporating the structural beam ( 1 ) as a bridge beam is also disclosed.

1 . A fabricated structural beam, comprising: 
 a longitudinally extending first member;    a longitudinally extending second member spaced from the first member; and,    at least one web member interconnecting the first and second members, wherein the beam has a narrower lateral extent at the second member than at the first member.    
     
     
         2 . A beam as claimed in    claim 1   , wherein the beam has a lateral extent which narrows from the first member to the second member.  
     
     
         3 . A beam as claimed in    claim 1   , wherein the beam tapers in lateral extent from the first member to the second member.  
     
     
         4 . A beam as claimed in    claim 1   , wherein the first member is a plate member.  
     
     
         5 . A beam as claimed in    claim 1   , wherein the second member is a tube member.  
     
     
         6 . A beam as claimed in    claim 1   , wherein the first member is a plate member and the second member is a tube member, and the tube member extends parallel, and in spaced relation, to a plane of the plate member.  
     
     
         7 . A beam as claimed in    claim 6   , wherein the tube member is laterally narrower than the plate member thereby providing the beam with the narrower lateral extent.  
     
     
         8 . A beam as claimed in    claim 6   , wherein the plate member and tube member each have a central longitudinal axis, and the axes lie in a common plane extending transverse of the plate member.  
     
     
         9 . A beam as claimed in    claim 5   , wherein the tube member has a cylindrical cross sectional shape.  
     
     
         10 . A beam as claimed in    claim 1   , wherein a pair of web members are provided, extending along and between the first and second members in spaced apart relation to one another.  
     
     
         11 . A beam as claimed in    claim 10   , wherein the first member has a pair of longitudinally extending opposite edge regions, and each web member has a longitudinally extending connection region connected along the first member adjacent a respective edge region thereof.  
     
     
         12 . A beam as claimed in    claim 11   , wherein the web members are connected to the first member laterally inwardly of the edge regions so that the edge regions project laterally outwardly of the web members.  
     
     
         13 . A beam as claimed in    claim 10   , wherein the second member has a pair of longitudinally extending opposite side regions, and each web member has a longitudinally extending connection region connected along the second member at respective side regions thereof.  
     
     
         14 . A beam as claimed in    claim 10   , wherein the first member has a pair of longitudinally extending opposite edge portions, the second member has a pair of longitudinally extending opposite side regions, and the web members are formed from a unitary web plate shaped to extend outwardly about the second member with spaced apart portions of the web plate extending from the second member to the first member, the web plate having longitudinally extending edge regions connected along the first member adjacent the respective edge regions thereof, and longitudinally extending transitional regions between the web plate portions connected along the second member at the side regions thereof.  
     
     
         15 . A beam as claimed in    claim 10   , wherein the web members are connected to the first and second members by welding.  
     
     
         16 . A beam as claimed in    claim 1   , wherein the beam is of generally triangular shape in transverse cross section, the first member providing one side of that shape, the second member providing an apex of that shape, and the web member providing the remaining sides of that shape.  
     
     
         17 . A fabricated structural beam, comprising: 
 a longitudinally extending top plate having a pair of longitudinally extending opposite edge regions;    a longitudinally extending cylindrical bottom tube, the bottom tube being spaced from and extending parallel with the top plate equidistant from the edge regions of the top plate; and,    a web plate of generally V shape in transverse cross section, the web plate providing a pair of web portions and a bend portion between the web portions, the bend portion extending about the bottom tube so that the bottom tube nests along the web plate, the web plate being connected to the bottom tube along opposite side regions thereof, and the web portions extending one from each side of the bottom tube to the top plate, each web portion having a longitudinally extending connection region connected along the top plate adjacent a respective edge region of the top plate, wherein the beam tapers in lateral extent from the top plate to the bottom tube.    
     
     
         18 . A torsion beam crane, comprising: 
 a bridge beam for spanning a load working area, the bridge beam having a longitudinally extending top plate with a pair of longitudinally extending opposite edge regions, a longitudinally extending bottom tube spaced from and extending parallel with the top plate, and at least one side web interconnecting the top plate and bottom tube, wherein the beam has a narrower lateral extent at the bottom tube than at the top plate;    a trolley mounted on the beam for movement therealong, the trolley being located adjacent the top plate and cantilevered from one side of the beam; and,    a hoist carried by the trolley so as to be positioned to the one side of the beam, the hoist including a hook unit which can be raised and lowered relative to the trolley during operation of the hoist, the narrower lateral extent of the beam adjacent the bottom tube member providing a clearance space to the one side of the beam to enable raising of the hook unit into a position adjacent the one side of the beam during use of the crane.    
     
     
         19 . A torsion beam crane as claimed in    claim 18   , wherein the trolley has wheels engaging the longitudinally extending edge regions of the top plate so as to mount the trolley for movement along the top plate.  
     
     
         20 . A torsion beam crane as claimed in    claim 19   , wherein the longitudinally extending edge regions project laterally outwardly of the web member and provides opposed running surfaces for the wheels of the trolley.  
     
     
         21 . A torsion beam crane as claimed in    claim 18   , and including a bogie connected at each end of the bridge beam for mounting the crane on rails for travel along the rails over the load working area.  
     
     
         22 . In a torsion crane, comprising: 
 a bridge beam for spanning a load working area, the bridge beam having a longitudinally extending top plate;    a trolley mounted on the top plate for movement therealong, and being cantilevered from one side of the beam; and    a hoist carried by the trolley so as to be positioned to the one side of the beam, the hoist including a hook unit which can be raised and lowered relative to the trolley during operation of the hoist;    the improvement comprising: 
 the bridge beam having a longitudinally extending bottom tube spaced from and extending parallel with the top plate, and at leat one side web interconnecting the top plate and bottom tube, wherein the beam has a narrower lateral extent at the bottom tube than at the top plate to provide a clearance space to the one side of the beam to enable raising of the hook unit into the clearance space to the one side of the beam.