| 摘要 |
An objective of the present invention is to further prevent atmosphere from being exposed to an external space from an inner part of a furnace body. A roller hearth kiln corresponding to a heat treatment apparatus according to the present invention includes a furnace body (11) forming a first space (11a) and a wall structure (30) formed therein with a second space (30a) communicating with the first space (11a) and having first and second wall parts (31, 32). A rotational body (60), which can carry a workpiece (96) in the first space (11a), sequentially passes through a first wall part (31), a second space (30a), and a second wall part (32) toward an external space from the first space (11a) so that one end of the rotational body (60) protrudes from the second wall part (32). A first bearing (40) is installed on the first wall part (31) having gaps (44a, 45a) to rotatably support the rotational body (60) while gas can flow in a direction in which the rotational body (60) passes through. A second bearing (50) is installed on the second wall part (32) to rotatably support the rotational body (60) and having higher a sealing property as compared with that of the first bearing (40). Gas having pressure higher than that of the atmosphere of the first space (11a) is supplied to the second space (30a) from a second space feeding port (33). |
