Patent ID: 9644524
Date: 2017-05-09
CPC Classifications: F01P

Claim:
1. A cooling water passage structure comprising: an internal combustion engine; a water pump; and a communication member having a cooling water communication passage for supplying cooling water from the water pump to a cooling water passage in the internal combustion engine, wherein the cooling water communication passage is formed by a water pump housing containing the water pump, a first cooling water passage, and a second cooling water passage; cooling water from the water pump housing passes through the first cooling water passage and the second cooling water passage to reach the cooling water passage in the internal combustion engine; the second cooling water passage is a cylindrical passage extending in a direction orthogonal to an operating axis of the water pump, the second cooling water passage being displaced from an operating plane of the water pump; the first cooling water passage has a triangular part with a substantially triangular shape that widens from a vertex on the upstream side and an upper communication part; the upper communication part is configured to allow an upper portion of the triangular part to communicate with the second cooling water passage; and the upper communication part extends to the second cooling water passage and has substantially a same width as a width of the upper surface of the triangular part.