Vehicle braking control
First Claim
1. A method of operating an engine having at least one cylinder and an intake manifold for directing air to the cylinder, comprising:
- discontinuing combustion in the cylinder for at least one cycle by temporarily halting delivery of fuel to the cylinder;
during a first condition after combustion is discontinued, operating the cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve closed while opening, closing, and opening the other of said intake valve and said exhaust valve;
during a second condition after combustion is discontinued, wherein said second condition includes a request to increase the vacuum level within the intake manifold, varying an operation of at least one of the intake valve and the exhaust valve to increase air flow through the cylinder, and subsequently varying an operation of at least one of the intake valve and the exhaust valve to reduce air flow through the cylinder when the request is satisfied; and
resuming combustion in the cylinder by re-initiating delivery of fuel to the cylinder, wherein the amount of fuel delivered to the cylinder during a number of cycles after resuming combustion is based on an amount of oxygen provided to the exhaust during said discontinued combustion operation.
2 Assignments
0 Petitions
Accused Products
Abstract
A method of operating an engine for a vehicle having at least a first cylinder, the method comprising of operating the first cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve of the first cylinder closed while opening, closing, and opening the other of the intake valve and the exhaust valve during a cycle of the first cylinder and during a first vacuum level of an intake manifold upstream of the first cylinder; and operating the first cylinder to provide at least one of compression braking and expansion braking by operating both the intake valve and the exhaust valve of the first cylinder during a cycle of the first cylinder to allow at least some air to flow through the first cylinder during a second vacuum level of the intake manifold.
-
Citations
20 Claims
-
1. A method of operating an engine having at least one cylinder and an intake manifold for directing air to the cylinder, comprising:
-
discontinuing combustion in the cylinder for at least one cycle by temporarily halting delivery of fuel to the cylinder; during a first condition after combustion is discontinued, operating the cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve closed while opening, closing, and opening the other of said intake valve and said exhaust valve; during a second condition after combustion is discontinued, wherein said second condition includes a request to increase the vacuum level within the intake manifold, varying an operation of at least one of the intake valve and the exhaust valve to increase air flow through the cylinder, and subsequently varying an operation of at least one of the intake valve and the exhaust valve to reduce air flow through the cylinder when the request is satisfied; and resuming combustion in the cylinder by re-initiating delivery of fuel to the cylinder, wherein the amount of fuel delivered to the cylinder during a number of cycles after resuming combustion is based on an amount of oxygen provided to the exhaust during said discontinued combustion operation. - View Dependent Claims (2)
-
-
3. A method of operating an engine for a vehicle having at least a first cylinder, the method comprising:
-
operating the first cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve of the first cylinder closed while opening, closing, and opening the other of the intake valve and the exhaust valve during a cycle of the first cylinder and during a first vacuum level of an intake manifold upstream of the first cylinder; and operating the first cylinder to provide at least one of compression braking and expansion braking by operating both the intake valve and the exhaust valve of the first cylinder during a cycle of the first cylinder to allow at least some air to flow through the first cylinder during a second vacuum level of the intake manifold. - View Dependent Claims (4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A method of operating an engine having a plurality of cylinders, comprising:
-
during an increased vacuum level request, increasing a vacuum level of an intake manifold by increasing a number of cylinders providing at least one of compression braking and expansion braking by operating at least one intake valve and at least one exhaust valve to allow at least some air to flow through the first cylinder in response to reduced vacuum; and during a decreased vacuum level request, decreasing the vacuum level and decreasing air flow through the engine by increasing a number of cylinders providing at least one of compression braking and expansion braking by holding closed one of an intake valve and an exhaust valve while opening, closing, and opening the other of the intake valve and the exhaust valve in response to increased vacuum. - View Dependent Claims (16, 17, 18, 19, 20)
-
Specification