Piston engine drivable using a steam power process

Abstract

A piston engine ( 1 ) that can be driven using a steam power process and is used in particular for utilizing the waste heat from an internal combustion engine comprises a cylinder bore ( 5 ), a cylinder piston ( 6 ) which is arranged in the cylinder bore ( 5 ) and delimits an operating space ( 8 ) in the cylinder bore ( 5 ), a rod ( 21 ) which is connected to the cylinder piston ( 6 ), and a bearing point ( 37 ) on which the rod ( 21 ) and the cylinder piston ( 6 ) connected to the rod ( 21 ) are mounted. A peripheral gap ( 28 ) is predefined between the cylinder piston ( 6 ) and the cylinder bore ( 5 ), thus preventing frictional wear between the cylinder piston ( 6 ) and the cylinder bore ( 5 ), which is particularly advantageous when a water-based working fluid is conducted through the operating space ( 8 ) since steam has no lubricity.

1 . A piston engine ( 1 ) that can be driven using a steam power process, with at least one cylinder bore ( 5 ), a cylinder piston ( 6 ) arranged in the cylinder bore ( 5 ), which bounds a working chamber ( 8 ) in the cylinder bore ( 5 ), a rod ( 21 ) at least indirectly connected to the cylinder piston ( 6 ) and at least one bearing point ( 37 ), on which the rod ( 21 ) and the cylinder piston ( 6 ) connected to the rod ( 21 ) are supported, wherein a circumferential gap ( 28 ) is defined between the cylinder piston ( 6 ) and the cylinder bore ( 5 ) and wherein the rod ( 21 ) connects the cylinder piston ( 6 ) to a crank loop ( 18 ). 
     
     
         2 . The piston engine as claimed in  claim 1 , characterized in that an external diameter ( 26 ) of an exterior ( 25 ) of the cylinder piston ( 6 ) is defined to be smaller than an internal diameter ( 27 ) of the cylinder bore ( 5 ). 
     
     
         3 . The piston engine as claimed in  claim 1 , characterized in that at least one sealing element ( 31 ,  32 ) is arranged on an exterior ( 25 ) of the cylinder piston ( 6 ). 
     
     
         4 . The piston engine as claimed in  claim 3 , characterized in that at least one circumferential recess ( 29 ,  30 ) is formed on the exterior ( 25 ) of the cylinder piston ( 6 ), that the sealing element ( 31 ,  32 ) is formed as an annular sealing element ( 31 ,  32 ) and that the annular sealing element ( 31 ,  32 ) is inserted in the circumferential recess ( 29 ,  30 ). 
     
     
         5 . The piston engine as claimed in  claim 1 , characterized in that the rod ( 21 ) is at least essentially rigidly connected to the cylinder piston ( 6 ), that the bearing point ( 37 ) is in the form of a bearing bore ( 36 ) in which the rod ( 21 ) is guided, and that the cylinder piston ( 6 ) is at least approximately centrally orientated on a longitudinal axis ( 7 ) of the cylinder bore ( 5 ) by the guidance of the rod ( 21 ) in the bearing bore ( 36 ). 
     
     
         6 . The piston engine as claimed in  claim 5 , characterized in that the bearing bore ( 36 ) is arranged in a housing part ( 35 ), which is arranged between the cylinder bore ( 5 ) and a crankshaft chamber ( 15 ). 
     
     
         7 . The piston engine as claimed in  claim 1 , characterized in that a crankshaft chamber ( 15 ) is provided, that the rod ( 21 ) is led out of the cylinder bore ( 5 ) via the bearing point ( 37 ) into the crankshaft chamber ( 15 ), that a crankshaft ( 16 ) is arranged in the crankshaft chamber ( 15 ) and that the rod ( 21 ) works in conjunction with the crankshaft ( 16 ) by means of the crank loop ( 18 ). 
     
     
         8 . The piston engine as claimed in  claim 1 , characterized in that at least one further cylinder bore ( 5 ′), a further cylinder piston ( 6 ′) arranged in the further cylinder bore ( 5 ′) and which bounds a further working chamber ( 8 ′) in the further cylinder bore ( 5 ′), a further rod ( 21 ′), which is at least indirectly connected to the further cylinder piston ( 6 ′), and at least one further bearing point ( 37 ′) are provided, wherein the further rod ( 21 ′) is supported on the further bearing point ( 37 ′) and wherein a circumferential gap ( 28 ′) is defined between the further cylinder piston ( 6 ′) and the further cylinder bore ( 5 ′) 
     
     
         9 . The piston engine as claimed in  claim 8 , characterized in that the further rod ( 21 ′) is at least substantially rigidly connected to the further cylinder piston ( 6 ′), that the further bearing point ( 37 ′) is formed by a further bearing bore ( 36 ′), in which the further rod ( 21 ′) is guided, and that the further cylinder piston ( 6 ′) is at least approximately centrally orientated on a longitudinal axis ( 7 ) of the further cylinder bore ( 5 ′) by the guidance of the further rod ( 21 ′) in the further bearing bore ( 36 ′). 
     
     
         10 . The piston engine as claimed in  claim 8 , characterized in that an external diameter ( 26 ′) of an exterior ( 25 ′) of the further cylinder piston ( 6 ′) is defined to be smaller than an internal diameter ( 27 ′) of the further cylinder bore ( 5 ′). 
     
     
         11 . The piston engine as claimed in  claim 8 , characterized in that an at least one sealing element ( 31 ′,  32 ′) is arranged on an exterior ( 25 ′) of the further cylinder piston ( 6 ′). 
     
     
         12 . The piston engine as claimed in  claim 11 , characterized in that an external diameter ( 26 ′) of an exterior ( 25 ′) of the further cylinder piston ( 6 ′) is defined to be smaller than an internal diameter ( 27 ′) of the further cylinder bore ( 5 ′).