To provide a fault detection method for detecting short-circuit faults in an injector apparatus at engine start-up.
This injector apparatus includes one or a plurality of piezoelectric fuel injectors 12a, 12b which are connected in a drive circuit 20. In one aspect, potential VB at a bias point PB in the drive circuit is determined and compared with a predicted voltage VPB. A short circuit fault signal is generated if the potential at the bias point is not within a predetermined tolerance voltage VTOL of the predicted voltage. In another aspect of the invention, a first charge pulse is applied to the injectors to charge the injectors. A discharge current path 38 is formed during a delay period Δt following the first charge pulse by closing a discharge switch Q2. A faulty injector may discharge through the discharge current path during the delay period Δt. A second charge pulse is applied to the injectors following the delay period. A current flow IS is sensed during the second charge pulse, and a short-circuit warning signal is generated if the current flow during the second charge pulse exceeds a predetermined threshold current.
| JP2002246667A | 2002-08-30 | |||
| JP2001349241A | 2001-12-21 | |||
| JP2002252990A | 2002-09-06 | |||
| JPH0573157A | 1993-03-26 |
| WO2005028836A1 | 2005-03-31 | |||
| WO2005106227A1 | 2005-11-10 |
小林 泰
千葉 昭男
富田 博行
西山 文俊
Next Patent: CAGE FOR ROLLING BEARING AND ROLLING BEARING USING THE SAME