Cylinder liner providing coolant shunt flow
A coolant-shunt-providing cylinder liner of the flanged type is provided with a shunt circuit within the liner for coolant flow through the liner. The shunt circuit includes an array of three annular cooling channels separated from each other by two annular ribs. The width (axial extent) of each channel is substantially less than half the axial extent of the liner's cylinder block engaging portion that is associated with the upper end of the liner. The width (axial extent) of the array of three channels is substantially greater than half the axial extent of the cylinder block engaging portion. Cutouts in the ribs are provided for distributing incoming coolant to the three cooling channels from a main coolant chamber of a cylinder block in which the liner is receivable.
1. A coolant-shunt-providing cylinder liner of the flanged type receivable and securable in a cylinder bore of a cylinder block of an internal combustion engine, said liner having a radial flange at the top end of said cylinder liner and positionable adjacent the combustion chamber of the engine, said liner having a cylinder block engagement portion immediately below said radial flange, said radial flange including a circumferentially extending stop shoulder at the junction between the radial flange and said cylinder block engagement portion, the lower end of said cylinder block engagement portion terminating at an annular diameter-reduction shoulder formed in the liner wall, the cylinder liner being capable of being supported and held within the cylinder block throughout the axial extent of said radial flange and said cylinder block engagement portion taken together, an array of three annular cooling channels each formed in the wall of said liner and each extending circumferentially around said liner and each extending in axial length within, and across substantially less than half of, the axial length of the upper cylinder block engaging portion of the liner, said array of cooling channels extending in axial length within, and across a substantial majority of, the axial length of the cylinder block engaging portion, said three cooling channels being partly defined by two ribs, said ribs extending circumferentially around said liner and being integral with the body of the liner, the peaks of said ribs being flat in profile and adapted for area contact with the cylinder block, said channels forming passages for coolant shunt flow in both circumferential directions, said flow being parallel in nature in both circumferential directions, two diametrically opposed shunt inlet regions associated with said liner and at each of which coolant is admitted from a coolant chamber to said array of cooling channels, two diametrically opposed shunt outlet regions associated with said liner and at each of which there is a collection passage arrangement whereby coolant is collected and emptied from said array of cooling channels, each of said shunt outlet regions being spaced around the liner circumference an angular distance of 90 degrees from both said shunt inlet regions, circumferentially aligned cutouts in said two ribs at each of said shunt inlet regions, and a cutout in at least one of said two ribs at each of said shunt outlet regions.
2. A cylinder liner as in claim 1 , said collection passage arrangements including circumferentially aligned cutouts in both said ribs at each of said shunt outlet regions.
3. A cylinder liner as in claim 1 , said array of cooling channels extending in axial length across at least 70% of the axial length of said cylinder block engaging portion.
4. A cylinder liner as in claim 3 , the height of said ribs in the radial direction exceeding their width in the axial direction by at least 25%.