Main buck unit for vehicle body assembling system and control method of the same

Abstract

A vehicle body assembling system forms a pre-buck section and a main buck section set along a transfer path of a floor assembly. A main buck unit is set at opposite sides of the transfer path in the main buck section, controls an upper portion of a side assembly in a state that a lower portion of each side assembly is pre-assembled to the floor assembly the pre-buck section, and assembles the upper portion of the side assembly and vehicle body parts using a second welding robot.

What is claimed is: 
     
         1 . A vehicle body assembling system, comprising:
 a pre-buck unit including a pre-buck section and a main buck unit including a main buck section that are set along a transfer path of a floor assembly,   wherein the main buck unit is formed in the main buck section, and while a side assembly is provided in each of opposite sides of a transfer path in the main buck section and a lower portion of each side assembly is pre-assembled to the floor assembly by the pre-buck unit, the vehicle body assembling system controls an upper portion of each side assembly and assembles the upper portion of each side assembly and vehicle body parts using a second welding robot.   
     
     
         2 . The vehicle body assembling system of  claim 1 , wherein, while the lower portion of each side assembly is welded to the floor assembly by the pre-buck unit, the main buck unit controls a width direction of the side assembly and welds the upper portion of the side assembly and the vehicle body parts using the second welding robot. 
     
     
         3 . The vehicle body assembling system of  claim 1 , wherein the main buck unit comprises a loading portion that controls the vehicle body parts that include a cowl, a roof rail, and a package tray and placing of the vehicle body parts in a regular position in the upper portion of the side assembly. 
     
     
         4 . The vehicle body assembling system of  claim 1 , wherein the main buck unit comprises a plurality of side jigs that control the upper portion of the side assembly that is different depending on a type of a vehicle, and a 4-sided rotation index that fixes the side jig. 
     
     
         5 . The vehicle body assembling system of  claim 4 , wherein the main buck unit detachably couples the side jig with respect to the rotation index by using a handling robot. 
     
     
         6 . A main buck unit in a vehicle body assembling system that sets a pre-buck section and a main buck section along a transfer path of a floor assembly and forms a pre-buck unit in the pre-buck section, wherein the main buck unit is formed in the main buck section, the main buck unit comprising:
 a plurality of side jigs detachably mounted to a handling robot in the main buck section and controlling an upper portion of a side assembly that is different depending on a type of a vehicle;   a rotation index coupled with the side jig in the main buck section, that is rotatable by a predetermined angle, and that is provided to be reciprocatively movable along a vehicle width direction at opposite sides of the transfer path; and   at least one second welding robot provided in the main buck section and welding the upper portion of the side assembly and vehicle body parts.   
     
     
         7 . The main buck unit for the vehicle body assembling system of  claim 6 , wherein the main buck unit comprises a loading portion provided to be movable along the transfer path in an upper side of the transfer path and being elevatable in the main buck section. 
     
     
         8 . The main buck unit of  claim 7 , wherein the loading portion controls the vehicle body parts that include a cowl, a roof rail, and a package tray, and places the vehicle body parts in regular positions in the upper portion of the side assembly. 
     
     
         9 . The main buck unit of  claim 6 , wherein a storage portion is provided in the main buck section to store the plurality of side jigs. 
     
     
         10 . The main buck unit of  claim 6 , wherein each of the side jigs comprises:
 a jig frame mounted to an arm front end of the handling robot in the main-buck section;   a plurality of third clampers provided in the jig frame, clamping the upper portion of the side assembly, and controlling a vehicle width direction of the side assembly; and   a plurality of second coupling pins provided in the jig frame and coupled with the rotation index.   
     
     
         11 . The main buck unit of  claim 10 , wherein the second coupling pin forms a round-shaped second ball coupling groove along a circumferential direction thereof. 
     
     
         12 . The main buck unit of  claim 6 , wherein the rotation index comprises:
 second movement members provided to be reciprocatively movable along a vehicle width direction by a driver in main buck frames at opposite sides of the transfer path;   a pair of index frames provided at a distance from each other on the second movement member;   a rotator including four sides where the side jigs that are different depending on a type of the vehicle are detachably coupled and rotatably provided in the index frame by the driver;   a plurality of jig coupling portions provided in the respective sides of the rotator and pin-coupled with the side jigs; and   a plurality of fourth clampers provided in the respective sides of the rotator and fixing the side jigs to the rotator.   
     
     
         13 . The main buck unit of  claim 12 , wherein the jig coupling portion is provided with a triangular structure in each side of the rotator. 
     
     
         14 . The main buck unit of  claim 12 , wherein the jig coupling portion comprises:
 a second pin housing to which a second coupling pin provided in the side jig is fitted; and   a second ball clamp provided in the second pin housing and clamping the second coupling pin using a plurality of balls.   
     
     
         15 . The main buck unit of  claim 14 , wherein the second ball clamp comprises a pair of second race members where the balls are rollably provided, and are provided to be movable to a center from an outer side of a circumferential direction of the second coupling pin by the driver. 
     
     
         16 . The main buck unit of  claim 15 , wherein the second coupling pin forms a round-shaped second ball coupling groove along a circumferential direction thereof. 
     
     
         17 . The main buck unit of  claim 16 , wherein the balls are coupled to the second ball coupling grooves by the second race members. 
     
     
         18 . The main buck unit of  claim 12 , wherein, in the index frame, a second location sensor that senses a location of the side assembly and controls a driver of the second movement member according to a sense signal is provided. 
     
     
         19 . The main buck unit of  claim 12 , wherein a vehicle type tag is provided in the side jig and a tag reader is provided in each side of the rotator. 
     
     
         20 . A method for controlling a main buck unit in a vehicle body assembling system, comprising:
 receiving, by a tag reader, vehicle type information of side jigs coupled to four sides of a rotation index;   determining, by a controller, whether a side jig that corresponds to a type of a next vehicle to be produced in addition to the side jig of the type of a vehicle that is currently produced is coupled to the rotation index;   when it is determined that a side jig of a type of the next vehicle to be produced is not coupled to the rotation index, separating the side jig mounted to an upper side of the rotation index and unloading the separated side jig in a storage portion in assembling of a side assembly of the type of the vehicle that is currently produced; and   selecting, by the controller, a side jig of a type of the next vehicle to be produced from the storage portion, and coupling the selected side jig to the upper side of the rotation index when the rotation index is moved backward after finishing assembly of the side jig of the type of the vehicle that is currently produced.   
     
     
         21 . The method for controlling the main buck unit of  claim 20 , wherein, when it is determined that the side jig of the type of the next vehicle to be produced is coupled to the rotation index, the side assembly of the type of the vehicle that is currently produced and a side assembly of the type of the next to be produced vehicle are assembled by rotating the rotation index and moving the rotation index back and forth. 
     
     
         22 . The method for controlling the main buck unit of  claim 20 , wherein the tag reader provided in each side of the rotation index receives vehicle type information stored in a vehicle type tag provided in the side jig.