Control system for vehicle

Patent metadata

Field	Value
Publication number	US-9951829-B2
Application number	US-201515128215-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Mar 28, 2014
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A selectable one-way clutch includes an engagement mechanism. The engagement mechanism is configured to be switched between an engaged state and a disengaged state. The engaged state is a state in which relative rotation between a first and a second members in one of a positive rotational direction and a reverse rotational direction is restricted. The disengaged state is a state in which the relative rotation between the first member and the second member in both of the positive and the reverse rotational direction is permitted. The electronic control unit is configured to apply torque to the one of the first member or the second member by using a motor such that relative rotation in the other one of the positive or the reverse rotational direction is generated between the first member and the second member when the engagement mechanism is switched from the engaged state to the disengaged state.

First claim

The invention claimed is:

1. A control system for a vehicle, the control system comprising:
a selectable one-way clutch including an engagement mechanism, the engagement mechanism including a first member and a second member, the second member being configured to rotate relative to the first member, the engagement mechanism being configured to be switched between an engaged state and a disengaged state, the engaged state being a state in which relative rotation between the first member and the second member in one of a positive rotational direction and a reverse rotational direction is restricted, and the disengaged state being a state in which (i) the relative rotation between the first member and the second member in the one of a positive rotational direction and a reverse rotational direction and (ii) relative rotation between the first member and the second member in the other one of the positive rotational direction and the reverse rotational direction are permitted;
a motor configured to rotate one of the first member and the second member; and
an electronic control unit configured to apply torque to the one of the first member and the second member by using the motor such that the relative rotation in the other one of the positive rotational direction and the reverse rotational direction is generated between the first member and the second member when the engagement mechanism is switched from the engaged state to the disengaged state, the electronic control unit being configured to maintain a difference in rotational speed between the first member and the second member at a target value in a state that the relative rotation in the other one of the positive rotational direction and the reverse rotational direction is generated,
an internal combustion engine, the other one of the first member and the second member being configured such that torque of the internal combustion engine acts on the other one of the first member and the second member, and the target value being a value at which an absolute value of the rotational speed of the relative rotation in the other one of the positive rotational direction and the reverse rotational direction is maintained to be larger than “0” even when the torque of the internal combustion engine fluctuates in a process of switching the engagement mechanism from the engaged state to the disengaged state.

2. The control system according to claim 1 , wherein
the electronic control unit is configured to switch the engagement mechanism from the engaged state to the disengaged state in a state that the relative rotation in the other one of the positive rotational direction and the reverse rotational direction is generated.

3. The control system according to claim 1 , wherein
the electronic control unit is configured to continue maintaining the difference in rotational speed at the target value until the engagement mechanism is switched from the engaged state to the disengaged state.

4. The control system according to claim 1 , wherein
the electronic control unit is configured to switch the engagement mechanism to the disengaged state when a rotational speed of the relative rotation in the other one of the positive rotational direction and the reverse rotational direction reaches a predetermined reference rotational speed.

5. The control system according to claim 1 , wherein
the engagement mechanism includes an engagement piece, an actuator, and a sensor,
the engagement piece is supported by one of the first member and the second member,
the other one of the first member and the second member has a recessed section, the recessed section is configured to fit a tip of the engagement piece and the recessed section is engaged with the engagement piece,
the actuator is configured to operate the engagement piece to an engaged position and a disengaged position, the engaged position is a position at which the tip of the engagement piece is moved toward the other one of the first member and the second member by the actuator and the tip of the engagement piece is engaged with the recessed section, the disengaged position is a position at which the tip of the engagement piece is separated from the recessed section by the actuator,
the sensor is configured to detect an operation amount of the actuator, and
the electronic control unit is configured to determine that the engagement mechanism is switched to the disengaged state based on the operation amount of the actuator that is detected by the sensor.

6. The control system according to claim 1 , further comprising:
an output member; and
a power transmission mechanism including a fixed section and a first differential mechanism, wherein
the fixed section is coupled to the other one of the first member and the second member, the fixed section is configured not to rotate and move,
the first differential mechanism includes a first rotary element, a second rotary element, and a third rotary element, each of which performs a differential action with respect to each other, the internal combustion engine is coupled to the first rotary element, the motor and the other one of the first member and the second member are coupled to the second rotary element, and the first differential mechanism is configured such that torque is output from the third rotary element to the output member, and
the first differential mechanism is configured such that a speed of the internal combustion engine is reduced by reducing a rotational speed of the second rotary element that is in the same direction as a rotational direction of the internal combustion engine or by increasing a rotational speed of the second rotary element that is in an opposite direction from the rotational direction of the internal combustion engine.

7. The control system according to claim 6 , wherein
the rotational speed of the relative rotation in the other one of the positive rotational direction and the reverse rotational direction corresponds to a rotational speed of the motor that rotates the second rotary element in the opposite direction, and
the rotational speed of the relative rotation in the other one of the positive rotational direction and the reverse rotational direction corresponds to a rotational speed that is at least equal to a minimum rotational speed at which the internal combustion engine rotates independently.

8. The control system according to claim 1 , further comprising:
an output member; and
a power transmission mechanism including a fixed section, a first differential mechanism, and a second differential mechanism, wherein
the fixed section is coupled to the other one of the first member and the second member, the fixed section is configured not to rotate and move,
the first differential mechanism includes a first rotary element, a second rotary element, and a third rotary element, each of which performs a differential action with respect to each other, the internal combustion engine is coupled to the first rotary element, the motor is coupled to the second rotary element, and the first differential mechanism is configured such that torque is output from the third rotary element to the output member,
the second differential mechanism includes a fourth rotary element, a fifth rotary element, and a sixth rotary element, each of which performs a differential action with respect to each other, the first rotary element is coupled to the fourth rotary element, the second rotary element is coupled to the fifth rotary element, the one of the first member and the second member is coupled to the sixth rotary element, the fifth rotary element is configured to rotate in an opposite direction from a rotational direction of the fourth rotary element when the rotation of the sixth rotary element stops, and

Assignees

• Toyota Motor Co Ltd

Inventors

• Shibata Hiroyuki
• Shioiri Hiroyuki
• Komada Hideaki
• KUROSAKI Yuki

Classifications

• B60W20/30

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