Pump device and outboard motor

Abstract

The disclosure provides a pump device and an outboard motor equipped with the same. The pump device to be applied to an outboard motor includes a housing that has an insertion hole into which a drive shaft driven by an engine is to be inserted; and a resin cover member that is fixed to the housing to cover an outer wall surface of the housing in a region having the insertion hole. The cover member has a small-diameter insertion hole having an inner diameter smaller than the insertion hole to allow the drive shaft to be rotatably inserted thereto.

What is claimed is: 
     
         1 . A pump device to be applied to an outboard motor, comprising:
 a housing that has an insertion hole into which a drive shaft driven by an engine is to be inserted, and   a resin cover member that is fixed to the housing to cover an outer wall surface of the housing in a region having the insertion hole,   wherein the cover member has a small-diameter insertion hole having an inner diameter smaller than the insertion hole to allow the drive shaft to be rotatably inserted thereto.   
     
     
         2 . The pump device according to  claim 1 ,
 wherein the housing comprises a convex cylindrical portion that protrudes in an axial direction of the drive shaft to define a part of the insertion hole and the outer wall surface, and   the cover member is formed to cover a region comprising the convex cylindrical portion.   
     
     
         3 . The pump device according to  claim 2 ,
 wherein the convex cylindrical portion is a cylindrical portion that protrudes cylindrically around an axis of the drive shaft, and   the cover member comprises an annular flange portion in close contact with an outer wall surface around a root of the cylindrical portion; an outer peripheral wall portion that covers an outer peripheral surface of the cylindrical portion; and a bottom wall portion that covers an end surface of the cylindrical portion and defines the small-diameter insertion hole.   
     
     
         4 . The pump device according to  claim 2 ,
 wherein the convex cylindrical portion is a cylindrical portion that protrudes cylindrically around an axis of the drive shaft, and   the cover member comprises an annular flange portion in close contact with an outer wall surface around a root of the cylindrical portion; an outer peripheral wall portion that covers an outer peripheral surface of the cylindrical portion; a bottom wall portion that covers an end surface of the cylindrical portion; and an inner cylindrical portion that extends from the bottom wall portion inward in the axial direction to be closely fitted to the insertion hole and defines the small-diameter insertion hole.   
     
     
         5 . The pump device according to  claim 4 ,
 wherein the inner cylindrical portion comprises a spiral protruding portion formed spirally around the axis to define the small-diameter insertion hole.   
     
     
         6 . The pump device according to  claim 2 ,
 wherein the convex cylindrical portion is a cylindrical portion that protrudes cylindrically around an axis of the drive shaft, and   the cover member comprises an annular flange portion in close contact with an outer wall surface around a root of the cylindrical portion; an outer peripheral wall portion that covers an outer peripheral surface of the cylindrical portion; a bottom wall portion that covers an end surface of the cylindrical portion; and a tip cylindrical portion that extends from the bottom wall portion outward in the axial direction to define the small-diameter insertion hole.   
     
     
         7 . The pump device according to  claim 6 ,
 wherein the tip cylindrical portion comprises a spiral protruding portion formed spirally around the axis to define the small-diameter insertion hole.   
     
     
         8 . The pump device according to  claim 2 ,
 wherein the convex cylindrical portion is a cylindrical portion that protrudes cylindrically around an axis of the drive shaft, and   the cover member comprises an annular flange portion in close contact with an outer wall surface around a root of the cylindrical portion; an outer peripheral wall portion that covers an outer peripheral surface of the cylindrical portion; a bottom wall portion that covers an end surface of the cylindrical portion; and a long cylindrical portion that extends from the bottom wall portion inward in the axial direction to be closely fitted to the insertion hole and extends outward in the axial direction to define the small-diameter insertion hole.   
     
     
         9 . The pump device according to  claim 8 ,
 wherein the long cylindrical portion comprises a spiral protruding portion formed spirally around the axis to define the small-diameter insertion hole.   
     
     
         10 . The pump device according to  claim 3 ,
 wherein the cover member comprises, in the bottom wall portion, an annular protrusion portion that annularly abuts on the end surface of the cylindrical portion.   
     
     
         11 . The pump device according to  claim 3 ,
 wherein the cover member comprises, in the outer peripheral wall portion, a plurality of linear protruding portions that extend in the axial direction to come into close contact with the outer peripheral surface of the cylindrical portion and arranged around the axis.   
     
     
         12 . The pump device according to  claim 11 ,
 wherein the plurality of linear protruding portions are formed to have a height dimension with which the cover member is press-fitted to the cylindrical portion of the housing.   
     
     
         13 . The pump device according to  claim 1 , comprising:
 a pump element housed in the housing,   wherein the pump element comprises an inner rotor connected to a crankshaft of the engine and driven to rotate, and an outer rotor interlocked with the inner rotor.   
     
     
         14 . The pump device according to  claim 13 ,
 wherein the housing comprises an annular seal member disposed inside the cylindrical portion to be in close contact with an outer peripheral surface of the drive shaft inserted from the insertion hole and connected to the crankshaft.   
     
     
         15 . The pump device according to  claim 13 ,
 wherein the housing comprises a second annular seal member arranged to come into close contact with an outer peripheral surface of the crankshaft in a region between the pump element and the annular seal member in the axial direction.   
     
     
         16 . The pump device according to  claim 14 ,
 wherein the housing comprises a second annular seal member arranged to come into close contact with an outer peripheral surface of the crankshaft in a region between the pump element and the annular seal member in the axial direction.   
     
     
         17 . The pump device according to  claim 1 ,
 wherein the housing comprises an annular close contact region in which a flange portion of an oil pan is in annular close contact such that an outer wall surface outside a region covered by the cover member is arranged inside the oil pan comprised in the outboard motor.   
     
     
         18 . An outboard motor, comprising:
 an engine that comprises an engine body, a crankshaft that extends vertically in the engine body, an oil pan fixed to the engine body and storing oil, and a pump device fixed to the engine body and circulating the oil;   a body that holds the engine;   a drive shaft that is connected to the crankshaft and that rotates around an axis extending vertically, and   a propeller rotated by the drive shaft,   wherein the pump device is the pump device according to  claim 1 .