Patent ID: 7918199
Filing Date: 2011-04-05
Classification: F01L,F02F

Abstract:
1. A V-type engine comprising: first and second banks each of which includes a cylinder bore therein, and which are arranged in a V-shape so as to define a valley portion therebetween; a crankcase with which the first and second banks are continuously formed; a crankshaft supported by the crankcase; a cooling fin which protrudes on an outer wall of each of the banks; intake and exhaust valves which are arranged in a V-shape in a head portion of each of the banks; and a valve-operating device which drives the intake and exhaust valves to be opened and closed, the valve-operating device including: a camshaft being disposed above the crankshaft and driven by the crankshaft, first intake and exhaust cam followers and second intake and exhaust cam followers being moved up and down by intake and exhaust cams of the camshaft, respectively, first intake and exhaust push rods and second intake and exhaust push rods, the first intake and exhaust push rods having lower ends which are operatively connected respectively to the first intake and exhaust cam followers, and being disposed on the valley portion side of the first bank, the second intake and exhaust push rods having lower ends which are operatively connected respectively to the second intake and exhaust cam followers, and being disposed on the valley portion side of the second bank, and first intake and exhaust rocker arms and second intake and exhaust rocker arms, the first intake and exhaust rocker arms operatively connecting upper ends of the first intake and exhaust push rods respectively to the intake and exhaust valves of the first bank, the second intake and exhaust rocker arms operatively connecting upper ends of the second intake and exhaust push rods respectively to the intake and exhaust valves of the second bank, wherein the intake and exhaust rocker arms in each bank are arranged in a substantially inverted-V-shape in a plan view, so that end portions of the intake and exhaust rocker arms on the side of the corresponding intake and exhaust push rods are positioned adjacent to each other, thereby intake and exhaust push rods are positioned adjacent to each other, each of the cam followers is comprised of a boss portion swingably supported on a single cam follower shaft supported by the crankcase at a position directly above and in parallel with the camshaft, and a slipper portion being in sliding contact with a corresponding one of the intake and exhaust cams, the boss portions of the first and second intake cam followers abut against each other side by side on the cam follower shaft, while their slipper portions have end portions at one end along an axial direction of the camshaft protrude respectively in opposite directions to each other in such a manner that the slipper portions face each other across the intake cam located therebetween, the boss portions of the first and second exhaust cam followers abut against each other side by side on the cam follower shaft, while their slipper portions have end portions at one end along the axial direction of the camshaft protrude respectively in opposite directions to each other in such a manner that the slipper portions face each other across the exhaust cam located therebetween, the first and second intake cam followers and the first and second exhaust cam followers are arranged adjacent to one another on an intermediate portion of the cam follower shaft, which is supported, at opposite end portions thereof, by the crankcase, and corresponding to the cam followers, the intake and exhaust cams are arranged adjacent to each other.