Variable valve timing control device for internal combustion engine
First Claim
1. A variable valve timing control device for an internal combustion engine, comprising:
- a variable valve timing device which changes a valve timing of an exhaust valve of said internal combustion engine; and
a valve timing control means which controls said variable valve timing device, wherein said variable valve timing control means executes an exhaust valve advanced-closing control to control an exhaust valve closing timing to an advance side of an intake top dead center.
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Accused Products
Abstract
Either of intake and exhaust valves of an internal combustion engine is provided with a variable valve timing device. In a low-speed, low-load range, exhaust valve advanced-closing control is performed to close the exhaust valve at an earlier timing than the top dead center on the intake stroke, thereby trapping residual combustion gases in the cylinder. Furthermore, the cylinder temperature is raised by setting the intake valve opening timing at around the top dead center on the intake stroke or at a later timing thereof to thereby compress by the piston the residual gases in the cylinder during a period from closing the exhaust valve till the top dead center on the intake stroke. Thus it becomes possible to take in the air-fuel mixture into the cylinder at a higher cylinder temperature than the gas temperature of internal EGR caused by conventional valve overlap.
82 Citations
20 Claims
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1. A variable valve timing control device for an internal combustion engine, comprising:
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a variable valve timing device which changes a valve timing of an exhaust valve of said internal combustion engine; and
a valve timing control means which controls said variable valve timing device, wherein said variable valve timing control means executes an exhaust valve advanced-closing control to control an exhaust valve closing timing to an advance side of an intake top dead center. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
said variable valve timing device is provided on either of intake and exhaust sides of said internal combustion engine, said valve timing control means controls an intake valve opening timing during the exhaust valve advanced-closing control to around the intake top dead center or to a retard side of the intake top dead center. -
11. A variable valve timing control device according to claim 10, wherein said valve timing control means controls an intake valve closing timing during the exhaust valve advanced-closing control to an advance side of bottom dead center.
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12. A variable valve timing control device according to claim 1, wherein
said valve timing control means executes the exhaust valve closing timing to around the intake top dead center during idling operation, said valve timing control means executes the exhaust valve advanced-closing control during low-load operation, and said valve timing control means executes the exhaust valve closing timing to around the intake top dead center or to a retard side thereof during medium-load and high-load operation. -
13. A variable valve timing control device according to claim 1, wherein
said variable valve timing device is provided on either of intake and exhaust sides of said internal combustion engine, said valve timing control means controls an intake valve opening timing to around the intake top dead center or to a retard side thereof during part-load operation, and said valve timing control means controls the intake valve opening timing to an advance side of the intake top dead center during full-load operation. -
14. A variable valve timing control device according to claim 13, wherein
said valve timing control means controls an intake valve closing timing to an advance side of bottom dead center with a decrease in load during the part-load operation, and said valve timing control means controls the intake valve closing timing to a retard side of the bottom dead center during full-load operation.
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15. A variable valve timing control device for an internal combustion engine, comprising:
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a variable valve timing device which changes a valve timing of an exhaust valve of said internal combustion engine; and
a valve timing control means which controls said variable valve timing device, wherein said valve timing control means switches, in accordance with engine load, between an exhaust valve advanced-closing control which controls an exhaust valve closing timing to an advance side of an intake top dead center and an exhaust valve retarded-closing control which controls the exhaust valve closing timing to a retard side of the intake top dead center. - View Dependent Claims (16, 17, 18, 19, 20)
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Specification