Railway platform door device

1. A platform door device comprising a guide body installed on a platform, a door, a driving mechanism for moving the door forwardly and backwardly to close and open a gate on the platform, and a guiding mechanism for guiding the door being moved forwardly or backwardly, wherein:

the driving mechanism includes a motor, a rotation body adapted to be rotated by the motor, and a driven body adapted to be driven according to the rotation of the rotation body so as to move the door; and

the door moves forwardly or backwardly with at least a part of the door being located inside the guide body, and includes a panel-shaped main body, and a base segment, the base segment being detachably joined to the main body and to which the driven body is attached;

the guiding mechanism includes a linear rail extending in a direction of the movement of the door, and a guide block adapted to be slidingly moved with respect to the linear rail;

the main body includes a frame assembly that is formed in a frame shape by assembling a plurality of frame members together;

the base segment is joined to the frame assembly so that at least a part of the guide block is located within a thickness range of the frame assembly and includes a mounting portion and an extension portion, the mounting portion having a lower section, the extension portion extending downward from the lower section of the mounting portion and having a thickness less than a thickness of the frame assembly;

the lower section of the mounting portion having a portion that is located within the thickness range of the frame assembly and is mounted with one of the linear rail and the guide block; and

the driven body being located within the thickness range of the frame assembly at a position lower than one of the linear rail and the guide block and being joined to a lower end portion of the extension portion.

2. The platform door device according to claim 1 , wherein the driving mechanism includes a pair of pulleys separately arranged on respective ones of opposite sides of the rotation body, and wherein:

the rotation body has teeth;

the driven body consists of a belt member which is wound over the pair of pulleys and meshed with the teeth of the rotation body at a position between the pulleys; and

the lower end portion of the extension portion is provided with a first belt joining portion joined to one end of the belt member, and a second belt joining portion joined to the other end of the belt member while allowing the belt member to be tightened with a given tension.

3. The platform door device according to claim 2 , wherein a remaining one of the linear rail and the guide block is fixed to the guide body.

4. The platform door device according to claim 3 , wherein the extension portion is located on a side opposite to a track with respect to the linear rail and the guide block, and formed with a cutout for exposing at least a part of the linear rail and the guide block.

5. The platform door device according to claim 4 , which comprises a cover, for covering the cutout, that is detachably attached to the base segment.

6. The platform door device according to claim 1 , wherein a remaining one of the linear rail and the guide block is fixed to the guide body.

7. The platform door device according to claim 6 , wherein the extension portion is located on a side opposite to a track with respect to the linear rail and the guide block, and formed with a cutout for exposing at least a part of the linear rail and the guide block.

8. The platform door device according to claim 7 , which comprises a cover, for covering the cutout, that is detachably attached to the base segment.