| 摘要 |
The invention relates to a unit which can be lowered into a tank containing solids-laden liquid, is composed of a support frame (2) and a circulation device (1) attached thereto, and which can be moved up and down by means of a lifting apparatus on a guide tube (6) of rectangular cross-section arranged in the tank, rollers (8, 9) attached to the support frame and rolling down the external surfaces of the guide tube serving to facilitate the motion of the unit which is locked in the operating position and remains in contact with the guide tube. In order, on the one hand to enable easy upwards and downwards motion of the unit, but on the other hand to have a large rest surface between support frame and guide tube in the operating position of the unit, according to the invention it is proposed that the point of contact (3) for the lifting apparatus is offset from the centre of gravity (7) of the unit in the direction of the circulation device, that, seen from the direction of the circulation device and in relation to the guide tube, rollers are only arranged on the front and rear side, that the rollers can only be brought to lie against the outer surfaces of the guide tube after pivoting of the unit carried by the lifting apparatus, and that the support frame possesses rest surfaces (10, 11) which are pressed against the external surfaces of the guide tube in the operating position of the unit by the moment generated from the weight of the locked unit. <IMAGE> |
