Internal combustion engine for a motor vehicle
AssigneeDaimlerChrysler AG
InventorsHarald Pfeffinger, Heiko Sass
Life of this patent
Estimating the term…
Abstract
In an internal combustion engine for a motor vehicle, having a cylinder head and an engine block, each with a coolant inlet port and a coolant outlet port which is common to the cylinder head the engine block, a main coolant pump having an intake side connected to the coolant outlet port and a pressure side connected to a first control valve via which coolant reaches the inlet port of the cylinder head and the inlet port of the engine block depending on the temperature of the coolant, and to a method for operating such an internal combustion engine, wherein the main coolant pump is selectively actuated to pump the coolant through at least one of the cylinder head and the engine block or is shut down depending on the engine operating state.
Claims13
An internal combustion engine (6) for a motor vehicle, comprising
- a cylinder head (7) with a coolant inlet port (4) and a coolant return flow port (10),
- an engine block (8) with a coolant inlet port (5) and a coolant return flow port (10) common to the cylinder head (7) and the engine block (8),
- a main coolant pump (1) having an intake side which is connected to the coolant return flow port (10) and a pressure side which is connected to
- a first flow control unit (3) for controlling admission of coolant to the inlet port (4) of the cylinder head (7) and the inlet port (5) of the engine block (8),
- the main coolant pump (1) being switchable on and off depending on the cooling requirement for the cylinder head (7) and the engine block (8),
- a second flow control unit (17) disposed in a coolant return line of the internal combustion engine (6) for returning the coolant, depending on the temperature, to the intake of the main coolant pump (1) selectively either in a large circuit (20) which includes an air/fluid cooler (21) or in a small circuit (18) which bypasses the air/fluid cooler (21),
- a heating circuit line (12) which is branched off from a coolant return flow line of the internal combustion engine (6) for conducting part of the coolant back to the main coolant pump (1) bypassing the second flow control unit (17),
- and an additional electric coolant pump (16) arranged in the heating circuit line (12).
A method for operating an internal combustion engine for a motor vehicle, comprising:
- a cylinder head (7) with a coolant inlet port (4) and a coolant return flow port (10),
- a engine block (8) with a coolant inlet port (5) and a coolant return flow port (10) common to the cylinder head (7) and the engine block (8),
- a main coolant pump (1) having an intake side which is connected to the coolant return flow port (10) and a pressure side which is connected to
- a first flow control unit (3) for controlling admission of coolant to the inlet port (4) of the cylinder head (7) and the inlet port (5) of the engine block (8),
- the main coolant pump (1) being switchable on and off depending on the cooling requirement for the cylinder head (7) and the engine block (8), said method comprising the steps of:
- switching the main coolant pump (1) off if the internal combustion engine does not require any cooling,
- switching the main coolant pump (1) on so that coolant is circulated through at least one of the cylinder head (7) and the engine block (8) if cooling is necessary and,
- increasing the coolant flow by the operation of an additional electric coolant pump (16) disposed in the heating circuit (12).
Dependencies are inferred from the claim text.