Overhead conveyor

Abstract

An overhead conveyor includes a monorail, a driving trolley having a drive wheel rolling along the monorail and a motor driving the drive wheel, a driven trolley disposed to be spaced apart from the driving trolley on the monorail and having a driven wheel rolling along the monorail, a hanger operatively suspended from the monorail, a first friction plate disposed on the hanger, a plurality of first jigs extending towards the first friction plate along the monorail, and a friction drive unit having a friction drive wheel disposed on the first jig so as to convey the first friction plate in a running direction and a drive motor driving the friction drive wheel.

What is claimed is: 
     
         1 . An overhead conveyor comprising:
 a monorail ( 100 ) disposed on an upper side of a working space;   a driving trolley ( 210 ) having a drive wheel ( 211 ) rolling along the monorail ( 100 ), and a motor ( 212 ) driving the drive wheel ( 211 );   a driven trolley ( 220 ) disposed to be spaced apart from the driving trolley ( 210 ) on the monorail ( 100 ) and having a driven wheel ( 221 ) rolling along the monorail ( 100 );   a hanger ( 400 ) operatively suspended from the monorail ( 100 ) through a first frame ( 214 ) of the driving trolley ( 210 ) and a second frame ( 224 ) of the driven trolley ( 220 ) so as to carry an object thereon;   a first friction plate ( 500 ) disposed on one side of a flat upper end of the hanger ( 400 );   a plurality of first jigs ( 121 ) extending from the upper side of the working space towards the first friction plate ( 500 ) along the monorail ( 100 ); and   a friction drive unit ( 600 ) having a friction drive wheel ( 610 ) disposed on a lower end of the first jig so as to convey the first friction plate ( 500 ) in a running direction and a drive motor ( 620 ) driving the friction drive wheel ( 610 ),   wherein the hanger ( 400 ) is able to be run along the monorail ( 100 ) through driving of the driving trolley ( 210 ) and/or friction drive unit ( 600 ).   
     
     
         2 . The overhead conveyor according to  claim 1 , wherein the overhead conveyor includes:
 a second friction plate ( 500 ′) disposed on the other side of the flat upper end of the hanger in such a manner as to be arranged parallel with the first friction plate ( 500 ) relative to the monorail ( 100 );   a plurality of second jigs ( 122 ) extending from the upper side of the working space towards the second friction plate ( 500 ′) along the monorail ( 100 ); and   a support wheel ( 710 ) disposed on a lower end of the second jig so as to convey the second friction plate ( 500 ′) in a running direction.   
     
     
         3 . The overhead conveyor according to  claim 1 , wherein the driving trolley ( 210 ) includes a toggle clamp ( 213 ). 
     
     
         4 . The overhead conveyor according to  claim 1 , wherein the friction drive unit ( 600 ) includes a displacement means displacing the friction drive wheel ( 610 ). 
     
     
         5 . The overhead conveyor according to  claim 2 , wherein the support wheel ( 710 ) includes a displacement means displacing the support wheel. 
     
     
         6 . The overhead conveyor according to  claim 2 , wherein the friction plate ( 500 ,  500 ′) has a plane part ( 511 ) and downwardly-inclined surfaces ( 512 ) on opposite ends of the plane part. 
     
     
         7 . The overhead conveyor according to  claim 6 , wherein the plane part of the friction plate ( 500 ,  500 ′) extends longer than a distance between two adjacent friction drive wheels ( 610 ) or support wheels ( 710 ).