Device for providing clean combustion air for the internal combustion engine of a working tool

Abstract

In a device for providing clean combustion air for an internal combustion engine of a working tool, provision is made for a cyclone filter into which ambient air contaminated with impurities can be sucked. A partial air flow contaminated with impurities can be extracted by suction from the cyclone filter, a partial air flow substantially freed from impurities is branched off from the cyclone filter and supplied to the internal combustion engine as combustion air. A fan which provides a flow of cooling air against the internal combustion engine, is at least partially accommodated in a housing. Provision is made in the housing for at least one suction bore, which leads into the housing and provision is made in the area of the suction bore for a flow element for creating a low pressure. The partial air flow contaminated with impurities is connected to the suction bore.

1 . A device for providing clean combustion air for the internal combustion engine of a working tool, in particular of a handheld working tool, such as a chainsaw, an angle grinder, a working tool for the yard and landscape maintenance and the like, wherein
 provision is made for a cyclone filter, into which ambient air, which is contaminated with impurities, can be sucked,   wherein a partial air flow, which is contaminated with impurities, can be extracted by suction from the cyclone filter,   wherein a partial air flow, which is substantially freed from impurities, is furthermore branched off from the cyclone filter and can be supplied to the internal combustion engine as combustion air,   and wherein provision is made for a fan, by means of which cooling air can flow against the internal combustion engine and   wherein the fan is at least partially accommodated in a housing, characterized in that   provision is made in the housing for at least one suction bore, which leads into the housing and that   provision is made in the area of the suction bore for a flow element for creating a low pressure, wherein   the partial air flow, which is contaminated with impurities, is connected to the suction bore.   
     
     
         2 . The device according to  claim 1 , characterized in that the housing encompasses a flow chamber, in which the fan is arranged so as to rotate about an axis, wherein the suction bore leads into the flow chamber, in particular wherein the fan creates an air flow in the mouth area of the suction bore. 
     
     
         3 . The device according to  claim 1 , characterized in that the air flow serves to flow against the internal combustion engine and in particular the cylinder of the internal combustion engine. 
     
     
         4 . The device according to  claim 1 , characterized in that the fan is equipped on one side with fan blades, which serve to create the air flow in the mouth area of the suction bore. 
     
     
         5 . The device according to  claim 1 , characterized in that the flow element is embodied as constriction contour in a housing part of the housing, in particular into which the suction bore leads and/or the constriction contour is embodied so as to be located opposite the mouth of the suction bore in the housing. 
     
     
         6 . The device according to  claim 5 , characterized in that the flow element, which is embodied as constriction contour, encompasses a profile of an upper wing side of an airfoil wing, wherein the suction bore leads into the flow chamber, preferably downstream from the highest profile point in the upper wing side. 
     
     
         7 . The device according to  claim 1 , characterized in that the flow element is embodied as airfoil wing profile, which is arranged close to the mouth of the suction bore in the housing, in particular in the flow chamber. 
     
     
         8 . The device according to  claim 7 , characterized in that the airfoil wing profile is arranged so that the air flow can flow completely around it at least from a bottom wing side and from an upper wing side, in particular wherein the airfoil wing profile is arranged in the air flow, with the upper wing side facing in the direction of the suction bore. 
     
     
         9 . A method for providing clean combustion air for an internal combustion engine of a working tool, in particular of a handheld working tool, such as a chainsaw, an angle grinder, a working tool for the yard and landscape maintenance and the like, wherein
 provision is made for a cyclone filter, into which ambient air, which is contaminated with impurities, is sucked,   wherein a partial air flow, which is contaminated with impurities, is extracted by suction from the cyclone filter,   wherein a partial air flow, which is substantially freed from impurities, is furthermore branched off from the cyclone filter and is supplied to the internal combustion engine as combustion air,   and wherein provision is made for a fan, by means of which cooling air flows against the internal combustion engine and   wherein the fan is at least partially accommodated in a housing, characterized in that   at least one suction bore is introduced into the housing and   wherein a low pressure is created in the area of the suction bore in connection with at least one flow element, wherein   the partial air flow, which is contaminated with impurities, is extracted by suction by means of the low pressure through the suction bore.   
     
     
         10 . The method according to  claim 9  for providing clean combustion air for an internal combustion engine of a working tool comprising a device for providing clean combustion air for the internal combustion engine of a working tool, in particular of a handheld working tool, such as a chainsaw, an angle grinder, a working tool for the yard and landscape maintenance and the like, wherein
 provision is made for a cyclone filter, into which ambient air, which is contaminated with impurities, can be sucked, 
 wherein a partial air flow, which is contaminated with impurities, can be extracted by suction from the cyclone filter, 
 wherein a partial air flow, which is substantially freed from impurities, is furthermore branched off from the cyclone filter and can be supplied to the internal combustion engine as combustion air, 
 and wherein provision is made for a fan, by means of which cooling air can flow against the internal combustion engine and 
 wherein the fan is at least partially accommodated in a housing, characterized in that 
 provision is made in the housing for at least one suction bore, which leads into the housing and that 
 provision is made in the area of the suction bore for a flow element for creating a low pressure, wherein 
 the partial air flow, which is contaminated with impurities, is connected to the suction bore. 
 
     
     
         11 . A working tool comprising a device according to  claim 1 , in particular for operating a method for providing clean combustion air for an internal combustion engine of the working tool, in particular of a handheld working tool, such as a chainsaw, an angle grinder, a working tool for the yard and landscape maintenance and the like, wherein
 provision is made for a cyclone filter, into which ambient air, which is contaminated with impurities, is sucked,   wherein a partial air flow, which is contaminated with impurities, is extracted by suction from the cyclone filter,   wherein a partial air flow, which is substantially freed from impurities, is furthermore branched off from the cyclone filter and is supplied to the internal combustion engine as combustion air,   and wherein provision is made for a fan, by means of which cooling air flows against the internal combustion engine and   wherein the fan is at least partially accommodated in a housing, characterized in that   at least one suction bore is introduced into the housing and   wherein a low pressure is created in the area of the suction bore in connection with at least one flow element, wherein   the partial air flow, which is contaminated with impurities, is extracted by suction by means of the low pressure through the suction bore.