Drive System for a Cleaning Head Disposed in a Tank

Abstract

When, according to the invention, constructing a drive system for rotating the cleaning head in a tank and allowing the system to comprise a hysteresis coupling having two magnetic parts which are present inside the liquid space ( 4 ) and outside this, respectively, a completely liquid-tight separation between the housing ( 2 ) and the gear ( 14 ) may be ensured. The magnetic part ( 8, 18 ) of the hysteresis coupling may be formed by electromagnets, and with a displaceable ( 13 ) position of the one part relative to the other part ( 11, 19 ) the coupling may be adjusted with respect to the transferred torque and/or speed.

1 . A drive system for rotating a cleaning head in a tank, said drive system comprising a housing ( 2 ) having a propeller ( 7 ) mounted in a liquid channel ( 4 ) to which cleaning liquid is supplied under pressure, as well as a gear which is driven by the propeller ( 7 ), and which is mounted separated from the cleaning liquid in the housing ( 2 ), said gear transferring the rotation produced by the propeller ( 7 ) to a reduced rotation of the cleaning head in the tank ( 1 ), wherein the rotation produced by the propeller ( 7 ) is transferred to the gear via a magnetic coupling having coupling parts, the one coupling part of which being disposed inside the housing in the liquid channel and the other coupling part of which being disposed outside the housing, and wherein the rotation from the propeller ( 7 ) is transferred to the gear via a hysteresis coupling comprising a rotating magnetic inductor ( 18 ) driven by the propeller ( 7 ) or a hysteresis part ( 19 ) in the housing ( 2 ) which drives a rotating part mounted outside the housing ( 2 ), either of a ferromagnetic hysteresis material ( 19 ) or a magnetic part ( 18 ) which is connected with the input shaft ( 12 ) of the gear characterized in that the coupling parts are configured as two concentrically mounted cylinders ( 16 , 19 ) with magnets ( 18 ) mounted on the cylinder ( 16 ) around the shaft ( 6 ) extending from the propeller ( 7 ) and hysteresis cylinder ( 19 ) placed on the outside of the cylinder ( 16 ) and connected to the gear thereby achieving a more compact and efficient coupling and drive system. 
   
   
       2 . A drive system according to  claim 1 , characterized in that the coupling part ( 19 ) outside the housing ( 2 ) may be displaced ( 13 ) for variably changing the distance to cooperating coupling part ( 8 ,  9  and  11 ) and thereby for variably transferring the torque and/or speed in the hysteresis coupling. 
   
   
       3 . A drive system according to  claim 1 , characterized in that the magnetic inductor is provided with a plurality of permanent magnets ( 18 ) for generating the necessary magnetic field strength and polarity. 
   
   
       4 . A drive system according to  claim 1 , characterized in that the magnetic inductor ( 16 ,  18 ) is provided with electromagnetic magnets for variable adjustment of the magnetic field strength instead of moving the hysteresis cylinder. 
   
   
       5 . A drive system according to  claim 1 , characterized in that the rotation of the gear is transferred to a drive shaft ( 15 ) for the cleaning head via a further hysteresis coupling. 
   
   
       6 . A drive system according to  claim 2 , characterized in that the magnetic inductor is provided with a plurality of permanent magnets ( 18 ) for generating the necessary magnetic field strength and polarity. 
   
   
       7 . A drive system according to  claim 2 , characterized in that the magnetic inductor ( 16 ,  18 ) is provided with electromagnetic magnets for variable adjustment of the magnetic field strength instead of moving the hysteresis cylinder. 
   
   
       8 . A drive system according to  claim 3 , characterized in that the magnetic inductor ( 16 ,  18 ) is provided with electromagnetic magnets for variable adjustment of the magnetic field strength instead of moving the hysteresis cylinder.