A rack transporting device for transporting at least one rack holding a plurality of containers, the device comprising:
- a first main transporting path through which the rack is transported in a short-side direction of the rack;
- a second main transporting path which extends parallel to the first main transporting path and through which the rack is transported in the short-side direction of the rack;
- a first auxiliary transporting path which extends in a direction orthogonal to the first main transporting path and the second main transporting path and connects between an end of the first main transporting path and an end of the second main transporting path, and through which the rack is transported in a longitudinal direction of the rack;
- a main transporting drive mechanism which simultaneously drives and transports the rack on the first main transporting path and the rack on the second main transporting path in a forward direction along which the racks are transported from the first main transporting path to the second main transporting path through the first auxiliary transporting path, the main transporting drive mechanism also simultaneously driving and transporting the rack on the first main transporting path and the rack on the second main transporting path in a reverse direction that is opposite to the forward direction;
- a first auxiliary transporting drive mechanism which drives and transports the rack on the first auxiliary transporting path, the first auxiliary transporting drive mechanism having a first claw member to be engaged with a receiving hole formed in a side surface of the rack along the longitudinal direction of the rack, the first auxiliary transporting drive mechanism feeding the first claw member engaged with the receiving hole, thereby driving and transporting the rack on the first auxiliary transporting path;
- a first end edge region arrival detector which detects that the rack arrives at a first end edge region, the first end edge region being an end edge of the first main transporting path for transport in the forward direction;
- a first receiving region arrival detector which detects that the rack arrives at a first receiving region on the second main transporting path, the first receiving region receiving the rack transported through the first auxiliary transporting path;
- and
- a first retraction detector which detects that the rack is retracted from the first receiving region, wherein:
- the first auxiliary transporting drive mechanism drives and transports the rack from the first end edge region toward the first receiving region;
- when the first receiving region arrival detector detects arrival of the rack at the first receiving region, the main transporting drive mechanism drives and transports the rack in the forward direction;
- when the first retraction detector detects retraction of the rack from the first receiving region, the first auxiliary transporting drive mechanism moves the first claw member to a retraction position which does not interfere with the rack on the first main transporting path and the rack on the second main transporting path;
- after the first claw member is moved to the retraction position, the main transporting drive mechanism drives and transports the rack in the reverse direction;
- when the first receiving region arrival detector detects that the rack is returned and arrives at the first receiving region, the first auxiliary transporting drive mechanism moves the first claw member to a start edge position at which the first claw member is engageable with a rack transported to the end edge region;
- after the first claw member is moved to the start edge position, the main transporting drive mechanism drives and transports the rack in the forward direction, thereby engaging the receiving hole of the rack with the first claw member;
- and
- when the first end edge region arrival detector detects arrival of the rack at the first end edge region, the main transporting drive mechanism is stopped, and the first auxiliary transporting drive mechanism drives and transports the rack from the first end edge region toward the first receiving region.