External gear machine

Abstract

The invention relates to an external gear machine ( 1 ) in particular an external gear pump or an external gear motor, having at least two gears ( 3, 4 ) that mesh with each other in external engagement, wherein the gears ( 3, 4 ) are surrounded by a housing ( 10 ), wherein one gear ( 4 ) has at least one bearing journal ( 7, 8 ) and the other gear ( 3 ) has a driving or driven journal ( 5 ), which are in each case mounted in a bearing bushing ( 38 ) so as to respectively be rotatable about a rotation axis ( 13, 14 ), wherein a bearing sleeve pp with an anti-twist element is arranged in the bearing bushing ( 38 ). In order to improve the external gear machine, in particular with regard to the materials that can be used for producing the bearing bushings and/or the service life, the anti-twist element of the bearing sleeve is arranged in a through-hole of the bearing bushing and is combined with a filter device and/or throttle device via which a working medium of the external gear machine ( 1 ) reaches the bearing sleeve.

1 . An external gear machine ( 1 ), having at least first and second gears ( 3 , 4 ) that mesh with each other in external engagement, wherein the gears ( 3 , 4 ) are enclosed by a housing ( 10 ), wherein the second gear ( 4 ) comprises at least one bearing journal ( 7 , 8 ) and the first gear ( 3 ) comprises a driving or driven journal ( 5 ), wherein the bearing journal and the driven journal are supported in respective bearing bushes ( 38 ; 58 , 59 ) so that the bearing journal and the driven journal are rotatable about respective axes of rotation ( 13 , 14 ), wherein bearing sleeves ( 40 ; 61 , 62 ) having respective torsional locks ( 44 ; 65 , 66 ) are arranged in respective ones of the bearing bushes ( 38 ; 58 , 59 ), characterized in that the torsional lock ( 44 ; 65 , 66 ) of each of the bearing sleeves ( 40 ; 61 , 62 ) is arranged in a through-hole ( 39 ; 70 ) in the associated bearing bush ( 38 ; 58 , 59 ) and is combined with a filter device and/or restriction device ( 45 ; 86 ) through which a working medium of the external gear machine ( 1 ) reaches the bearing sleeve ( 40 ; 61 , 62 ). 
     
     
         2 . The external gear machine as claimed in  claim 1 , characterized in that the filter device and/or restriction device ( 45 ; 86 ) combined with the torsional lock ( 44 ; 65 , 66 ) comprises a gap filter for the working medium. 
     
     
         3 . The external gear machine as claimed in  claim 1 , characterized in that the filter device and/or restriction device ( 45 ) combined with the torsional lock ( 44 ) comprises a body ( 46 ) having at least one flattening ( 50 ), which is arranged in the through-hole ( 39 ) in the bearing bush ( 38 ). 
     
     
         4 . The external gear machine as claimed in  claim 3 , characterized in that the body ( 46 ) comprises a torsional lock point ( 47 ) at an end facing the bearing sleeve ( 40 ), and a spacer ( 48 ) with a filter head ( 49 ) at an end remote from the bearing sleeve ( 40 ). 
     
     
         5 . The external gear machine as claimed in  claim 1 , characterized in that two radially adjacent bearing bushes ( 58 , 59 ) are connected to one another to form a double-gland bearing ( 60 ), wherein the filter device and/or restriction device ( 86 ) combined with the torsional lock comprises a connecting member ( 65 ), which connects two torsional locking elements ( 66 , 67 ) to one another and serves for fastening the filter device and/or restriction device ( 86 ) combined with the torsional lock to the double-gland bearing ( 60 ). 
     
     
         6 . The external gear machine as claimed in  claim 5 , characterized in that the double-gland bearing ( 60 ) comprises a locating slot ( 70 ), which extends between two working medium supply channels ( 71 , 72 ) through the bearing bushes ( 58 , 59 ) to the respective bearing sleeve ( 61 , 62 ) and serves to receive the connecting member with the torsional locking elements ( 66 , 67 ). 
     
     
         7 . The external gear machine as claimed in  claim 5 , characterized in that an edge area ( 85 ) is bent off from the connecting member ( 65 ) which, at least in the area of the supply channels ( 71 , 72 ), exercises a gap filter function for the working medium. 
     
     
         8 . The external gear machine as claimed in  claim 7 , characterized in that the edge area ( 85 ) bent off from the connecting member ( 65 ) between the supply channels ( 71 , 72 ) represents a limit stop ( 100 ) for the filter device and/or restriction device ( 86 ) combined with the torsional lock. 
     
     
         9 . The external gear machine as claimed in  claim 6 , characterized in that at least one cooling duct ( 54 ; 73 , 74 ), which extends from supply channels ( 71 , 72 ) in the bearing bush ( 38 ; 58 , 59 ) to at least one restriction passage ( 41 , 42 ; 75 , 76 , 77 ) in the bearing sleeve ( 40 ; 61 , 62 ), is provided between the bearing sleeve ( 40 ; 61 , 62 ) and the bearing bush ( 38 ; 58 , 59 ). 
     
     
         10 . (canceled) 
     
     
         11 . The external gear machine as claimed in  claim 1 , characterized in that at least one cooling duct ( 54 ; 73 , 74 ), which extends from the through-hole ( 39 ; 70 ) in the bearing bush ( 38 ; 58 , 59 ) to at least one restriction passage ( 41 , 42 ; 75 , 76 , 77 ) in the bearing sleeve ( 40 ; 61 , 62 ), is provided between the bearing sleeve ( 40 ; 61 , 62 ) and the bearing bush ( 38 ; 58 , 59 ).