Lifting Cradle

Abstract

A lifting cradle for use with a modular building system of the type in which pre-fabricated modules constructed off-site are inserted into openings in a support frame constructed on-site to produce a building according to a user's requirements. The lifting cradle has a central loading platform and two safety cages arranged on opposite sides of the platform for operatives to view and/or control installation of the module in the opening. The lifting cradle is temporarily attached to the building during installation of the module and a counterbalance mechanism is provided to maintain stability of the lifting cradle during installation. The lifting cradle may also be employed when removing modules from the building.

1 . A lifting cradle having a working platform to receive a module to be inserted in or removed from an opening in a building, and means for temporarily attaching the cradle to the building.  
   
   
       2 . A lifting cradle according to  claim 1  wherein the temporary attachment means comprises one or more electromagnets for releasably securing the cradle to a frame of the building.  
   
   
       3 . A lifting cradle according to  claim 1  wherein the temporary attachment means comprises temporary clamps, locating bolts or inserts or fixtures for releasably securing the cradle to a frame of the building.  
   
   
       4 . A lifting cradle according to  claim 1  wherein means is provided for reducing out of balance loads as the module is inserted in or removed from the opening.  
   
   
       5 . A lifting cradle according to  claim 4  wherein the out of balance reduction means comprises a counter balance weight movable in response to the direction of movement of the module to maintain the cradle in a stable condition.  
   
   
       6 . A lifting cradle according to  claim 5  wherein the out of balance reduction means is electronically controlled in response to movement of the module.  
   
   
       7 . A lifting cradle according to  claim 5  wherein the counter balance mechanism is provided on the platform.  
   
   
       8 . A lifting cradle according to  claim 4  wherein the out of balance means is provided or jib or lifting arm of a crane used to lift the cradle.  
   
   
       9 . A lifting cradle according to  claim 1  wherein at least one safety cage is provided for an operative to monitor and/or control insertion/removal of the module.  
   
   
       10 . A lifting cradle according to  claim 9  wherein the safety cage extends substantially the whole length of the platform.  
   
   
       11 . A lifting cradle according to  claim 9  wherein the safety cage allows an operative to access the platform.  
   
   
       12 . A lifting cradle according to  claim 1  wherein means is provided for aligning the platform with the opening in the building.  
   
   
       13 . A lifting cradle according to  claim 1  wherein means is provided to insert a module into an opening and/or to remove a module from an opening.  
   
   
       14 . A lifting cradle according to  claim 1  wherein means is provided to level a module installed in an opening.  
   
   
       15 . A lifting cradle according to  claim 1  wherein means is provided for monitoring operation of the cradle.  
   
   
       16 . A lifting cradle according to  claim 1  wherein means is provided for electronically controlling operation of the cradle.  
   
   
       17 . A method of installing a module in an opening of a support frame during construction of a modular building, the method including the steps of: 
 providing a lifting cradle having a working platform,    positioning a module to be installed on the working platform,    lifting the cradle to position the working platform adjacent to an opening in a support frame of the building,    temporarily attaching the lifting cradle to the support frame,    transferring the module from the working platform through the opening into the support frame,    releasing the lifting cradle from the support frame, and    lowering the lifting cradle.    
   
   
       18 . A method according to  claim 17  wherein counterbalance means is provided to maintain stability of the lifting cradle during installation of the module.  
   
   
       19 . A method according to  claim 17  wherein leveling means is provided for leveling the module in the support frame.  
   
   
       20 . A method according to  claim 17  wherein aligning means is provided for aligning the working platform with the opening in the support frame.