Device and method for transporting articles

An article transport device comprising:

• a housing including an internal space,
• a driving unit disposed on an upper portion of the housing and traveling along a driving rail installed on a ceiling,
• a hoist unit disposed in the internal space and gripping a first transported article, and
• an anti-drop unit disposed in the housing and preventing the first transport article from falling,
• wherein the anti-drop unit includes a stroke configured to move toward the internal space and a contact portion installed at one end of the stroke and contacting the first transport article,
• wherein the contact portion is disposed at a bottom-most end of the article transport device and has a stair-shaped shape comprising more than two steps that descend in a direction toward a center of the internal space, and every step of the more than two steps of contact portion is configured to support the first transport article and prevent the first transport article from dropping out of the internal space,
• wherein the hoist unit grips the first transport article and lifts the first transport article into the internal space,
• wherein the stroke stops when the contact portion contacts the first transport article as the stroke moves toward the internal space.

An article transport device comprising:

• a housing including an internal space;
• a driving unit disposed on an upper portion of the housing and traveling along a driving rail installed on a ceiling;
• a hoist unit disposed in the internal space and gripping a first transport article;
• an anti-drop unit disposed in the housing and including a stroke configured to prevent the first transport article from falling, and moving towards the interior space, and a contact portion installed at one end of the stroke and in contact with the first transport article;
• a first stroke sensor installed at a portion where the anti-drop unit and the housing are connected and detects whether the stroke has moved to a minimum range of motion and transmits a signal;
• a second stroke sensor installed at a portion where the anti-drop unit and the housing are connected and detects whether the stroke has moved to a maximum range of motion and transmits a signal;
• and
• a control portion that detects signals from the first stroke sensor and the second stroke sensor and stops the stroke, and
• wherein the contact portion is disposed at a bottom-most end of the article transport device and has a stair-shaped shape comprising more than two steps that descend in a direction toward a center of the internal space, and every step of the more than two steps of contact portion is configured to support the first transport article and prevent the first transport article from dropping out of the internal space.