Abstract: A projector 1 has a first casing 1A (including a first part 2 and a second part 3) and a second casing 1B (including a third part 4). The second casing 1B is moved between an enlarging position where the second casing 1B is protruded from the first casing 1A and a reducing position where the second casing 1B is retracted into the first casing 1A. As the second casing 1B moves to the enlarging position, the distance between the exhaust ports 45 and the exhaust fan 9 increases, so that the wind noise is restricted. As the second casing 1B moves to the reducing position, the exhaust ports 45 are concealed in the first casing 1A, so that the entry of the dust or the like into the projector 1 is prevented.

Abstract: A projector 1 has a first casing 1A (including a first part 2 and a second part 3) and a second casing 1B (including a third part 4). The second casing 1B is moved between an enlarging position where the second casing 1B is protruded from the first casing 1A and a reducing position where the second casing 1B is retracted into the first casing 1A. As the second casing 1B moves to the enlarging position, the distance between the exhaust ports 45 and the exhaust fan 9 increases, so that the wind noise is restricted. As the second casing 1B moves to the reducing position, the exhaust ports 45 are concealed in the first casing 1A, so that the entry of the dust or the like into the projector 1 is prevented.

Abstract: A rotating apparatus for rotating an object utilizes a worm gear in which worm wheel torque supplied from a rotation table can be transferred to a worm gear. In this way the invention avoids a conventional disengaging mechanism that disengages the rotating apparatus when torque is supplied from the rotation table. Further, spring members and stoppers physically define a first and second rotation ranges and a split cam shuts off a drive motor within the first rotation range. Still further, an anti-backlash member is provided on the worm gearing. To prevent pinched fingers and dust accumulation, a skirt is preferably provided on the bottom, front edge of the object being rotated which closes a gap between the object and a support surface when the object is placed on the rotating apparatus.