Injection control device

1. An injection control device configured to open and close a fuel injection valve by driving the fuel injection valve with a current to control fuel injection to an internal combustion engine, the injection control device comprising:

a booster circuit configured to boost a battery voltage;

a boosting control unit configured to perform boosting control on the booster circuit;

a charge control setting unit configured to set a charge prohibition time of the booster circuit for the boosting control unit; and

a maximum time specification unit configured to specify a maximum valve-closing detection time based on a valve-closing detection time,

wherein

the charge control setting unit is configured to set the maximum valve-closing detection time as the charge prohibition time for the boosting control unit.

2. The injection control device according to claim 1 , further comprising:

a learning time acquisition unit configured to

learn a valve-closing detection time when a minute injection for learning is performed in a period in which the maximum valve-closing detection time is set and

acquire a valve-closing detection learning time; and

a maximum value storage unit configured to store a maximum value of the valve-closing detection learning time as a learned maximum time.

3. The injection control device according to claim 2 , wherein:

the charge control setting unit is configured to

calculate a time obtained by adding a margin time to the learned maximum time as a learned valve-closing detection time, and

set the learned valve-closing detection time as the charge prohibition time to the boosting control unit in a next trip and a subsequent step.

4. The injection control device according to claim 2 , further comprising:

a maximum value update unit configured to update the learned maximum time,

wherein

the charge control setting unit is configured to

calculate, as an updated-learned valve-closing detection time, a time obtained by adding a margin time to the learned maximum time after update, and

set a calculated updated-learned valve-closing detection time as the charge prohibition time for the boosting control unit.

5. The injection control device according to claim 1 , wherein

the charge control setting unit is configured to set the charge prohibition time to a time equal to or less than an upper limit value for the boosting control unit.

6. An injection control device configured to open and close a fuel injection valve by driving the fuel injection valve with a current to control fuel injection to an internal combustion engine, the injection control device comprising:

a booster circuit configured to boost a battery voltage;

one or more processors; and

a memory coupled to the one or more processors and storing program instructions that when executed by the one or more processors cause the one or more processors to at least:

perform boosting control on the booster circuit;

set a charge prohibition time of the booster circuit; and

specify a maximum valve-closing detection time based on a valve-closing detection time; and

set the maximum valve-closing detection time as the charge prohibition time for the boosting control unit.