Multichamber ultrasonic sensor for determining a liquid level

Abstract

An ultrasound sensor for determining a fluid level with an elongated housing ( 1 ) which comprises a lid ( 2 ) and a floor ( 3 ), with a measuring chamber ( 4 ), arranged in the housing ( 1 ), in which a fluid has the same level as outside the measuring chamber ( 4 ), and with an ultrasound transmission receiver ( 5 ) on the floor ( 3 ) within or outside the housing ( 1 ) in the area of the measuring chamber ( 4 ), the transmitted sound signals of which are reflected on the surface of the fluid and received by the ultrasound transmission receiver ( 5 ), in order to determine the fluid level from the signal run time, wherein in the housing ( 1 ), alongside the measuring chamber ( 4 ), at least one further chamber ( 6, 7 ) is arranged at least partially in front of the measuring chamber ( 4 ) or at least partially around the measuring chamber ( 4 ), wherein the outermost chamber forms the inlet chamber ( 7 ), and that the chambers ( 4, 6, 7 ) are connected to each other.

1 . An ultrasound sensor for determining a fluid level, with
 an elongated housing ( 1 ) which comprises a lid ( 2 ) and a floor ( 3 )   a measuring chamber ( 4 ), arranged in the housing ( 1 ), in which a fluid comprises the same level as outside the measuring chamber ( 4 )   an ultrasound transmission receiver ( 5 ) on the floor ( 3 ) inside or outside the housing ( 1 ) in the area of the measuring chamber ( 4 ), the transmitted sound signals of which reflect on the surface of the fluid and are received by the ultrasound transmission receiver ( 5 ), in order to determine the fluid level from the signal run time, characterized in that in the housing ( 1 ) alongside the measuring chamber ( 4 ) at least one further chamber ( 6 ,  7 ) is arranged at least partially in front of the measuring chamber ( 4 ) or at least partially around the measuring chamber ( 4 ), wherein the outer chamber forms the inlet chamber ( 7 ), and that the chambers ( 4 ,  6 ,  7 ) are connected to each other.   
   
   
       2 . An ultrasound sensor according to  claim 1 , characterized in that the inlet chamber ( 7 ) and the measuring chamber ( 4 ) comprise an opening ( 8 ) on the side, respectively at a height close to the floor ( 3 ) of the housing ( 1 ), to enable the fluid to flow in and out. 
   
   
       3 - 20 . (canceled) 
   
   
       21 . An ultrasound sensor according to  claim 1 , characterized in that at least one housing ventilation opening ( 10 ) is arranged in the lid ( 2 ) or on an outer side of the inlet chamber ( 7 ) at a height close to the lid ( 2 ). 
   
   
       22 . An ultrasound sensor according to  claim 1 , characterized in that the lid ( 2 ) is closed at least in the area of the measuring chamber ( 4 ). 
   
   
       23 . An ultrasound sensor according to  claim 1 , characterized in that the measuring chamber ( 4 ) comprises on one outer side at a height close to the lid ( 2 ) above the maximum measurable fluid level at least one ventilation opening ( 11 ). 
   
   
       24 . An ultrasound sensor according to  claim 1 , characterized in that a calibration reflector ( 12 ) is arranged in the measuring chamber ( 4 ) below the minimum possible fluid level, and the fluid level can be determined from the run time ratio of the signal reflected on the surface of the fluid and on the calibration reflector ( 12 ). 
   
   
       25 . An ultrasound sensor according to  claim 1 , characterized in that the profile of at least one chamber ( 4 ,  6 ,  7 ) is essentially round or square. 
   
   
       26 . An ultrasound sensor according to  claim 1 , characterized in that the outer sides of the chambers ( 6 ) which are arranged between the inlet chamber ( 7 ) and the measuring chamber ( 4 ) are designed as walls which extend from the floor ( 3 ) at the most up to a height just below the minimum measurable fluid level. 
   
   
       27 . An ultrasound sensor according to  claim 26 , characterized in that the height and length of the outer side of the chamber ( 6 ) which is closest to the measuring chamber ( 4 ) are dimensioned in such a manner that the retention capacity of said chamber ( 6 ) is greater than the retention capacity of the measuring chamber ( 4 ) itself. 
   
   
       28 . An ultrasound sensor according to  claim 1 , characterized in that the outer side of the chambers ( 6 ) which are arranged between the inlet chamber ( 7 ) and the measuring chamber ( 4 ) extend from the floor ( 3 ) up to the lid ( 2 ), that on the outer side of said chambers ( 6 ) close to the lid ( 2 ), at least one ventilation opening ( 11 ) is arranged, and that on the outer side, at least of the chamber ( 6 ) which is closest to the measuring chamber ( 4 ), between the floor ( 3 ) and the lid ( 2 ), at a height below the minimum measurable fluid level, at least one opening ( 8 ) is arranged to enable the fluid to flow in and out. 
   
   
       29 . An ultrasound sensor according to  claim 28 , characterized in that the height in which an interim opening ( 13 ) is arranged, and the length of the outer side of the chamber ( 6 ) which is closest to the measuring chamber is dimensioned, in such a manner that the retention capacity of said chamber ( 6 ) is greater than the retention capacity of the measuring chamber ( 4 ) itself. 
   
   
       30 . An ultrasound sensor according to  claim 1 , characterized in that the outer sides of the chambers ( 6 ) which are arranged between the inlet chamber ( 7 ) and the measuring chamber ( 4 ) are designed as walls which extend from the floor ( 3 ) at least up to a height above the maximum measurable fluid level, and that said outer sides of the chambers ( 6 ) comprise at a height close to the floor ( 3 ) of the housing ( 1 ) one opening ( 8 ) respectively to enable the fluid to flow in and out. 
   
   
       31 . An ultrasound sensor according to  claim 30 , characterized in that the openings ( 8 ) are arranged in such a manner that the openings ( 8 ) in succession in the direction of the measuring chamber ( 4 ) are positioned as far away from each other as possible. 
   
   
       32 . An ultrasound sensor according to  claim 1 , characterized in that the outer sides of the chambers ( 6 ) which are arranged between the inlet chamber ( 7 ) and the measuring chamber ( 4 ) extend from the floor ( 3 ) to the lid ( 2 ), and that said outer sides of the chambers ( 6 ) comprise at a height close to the floor ( 3 ) of the housing ( 1 ) one opening ( 8 ) respectively to enable the fluid to flow in and out, and one ventilation opening ( 11 ) close to the lid ( 2 ). 
   
   
       33 . An ultrasound sensor according to  claim 32 , characterized in that the openings ( 8 ) are arranged in such a manner that the openings ( 8 ) in succession in the direction of the measuring chamber ( 4 ) are positioned as far away from each other as possible. 
   
   
       34 . An ultrasound sensor according to  claim 1 , characterized in that at least one chamber ( 6 ,  7 ) is arranged around or in front of the measuring chamber ( 4 ), and that at least in one chamber ( 4 ,  6 ,  7 ) a separation device ( 9 ) is provided, which pre-specifies the flow direction of the fluid on its journey from one chamber ( 4 ,  6 ,  7 ) into the next chamber ( 4 ,  6 ,  7 ) through the respective opening ( 8 ). 
   
   
       35 . An ultrasound sensor according to  claim 34 , characterized in that the separation device ( 9 ) is realised by a separating web ( 9 ). 
   
   
       36 . An ultrasound sensor according to  claim 34 , characterized in that the separation device ( 9 ) is realised by means of the fact that respectively, the outer sides of two successive chambers ( 4 ,  6 ,  7 ) touch each other at least at one point. 
   
   
       37 . An ultrasound sensor according to  claim 1 , characterized in that each chamber ( 6 ,  7 ) comprises at least one interim web ( 14 ), wherein on the interim web ( 9 ), at a height close to the floor ( 3 ) of the housing ( 1 ), an interim opening ( 13 ) is arranged to enable the fluid to flow in and out. 
   
   
       38 . An ultrasound sensor according to  claim 34 , characterized in that each chamber ( 6 ,  7 ) comprises at least one interim web ( 14 ), and that the separation devices ( 9 ) and the interim webs ( 14 ) are higher than the maximum measurable fluid level.