one of guide sliders 134 and side wall 118 of the guide rail so that sliding of the guide slider can be controlled wedge member 180 engages a flat recessed portion 182 of guide slider 134 in this embodiment braking shoe 144 is omitted guide slider 134 provides the necessary braking action instead of slide roller 132 fig1 shows another embodiment of the present invention which is another modification of the embodiment shown in fig7 to 9 a single handle 150 is used commonly for both purposes of door operation and brake release handle 150 is connected not only through a linkage 154 to the lock device but also through linkage 141 and a conversion plate 190 to brake mechanism 140 in operation whenever the door is opened the braking force is released whenever the door is closed also braking is released fig1 and 14 show another embodiment of the present invention a handle 250 for operating a door is attached to a base plate 252 in such a manner that it can rotate about a pair of shafts 256 a hole 201c is formed in outer panel 201b of door 201 base plate 252 is fixed at the periphery of hole 201c by means of bolts 254 an operation portion 258 and an actuating portion 259 of handle.