Apparatus for driving electrical loads provided at a car

• US 5,710,465 A
• Filed: 08/15/1996
• Issued: 01/20/1998
• Est. Priority Date: 08/31/1995
• Status: Expired due to Fees

• Current Assignee: Hitachi Car Engineering Company Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Original Assignee: Hitachi Car Engineering Company Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Inventors: Saito, Hiroyuki, Koni, Mitsuru
• Primary Examiner(s): Elms, Richard T.
• Application Number:
  US08/698,107
• Time in Patent Office: 523 Days
• Field of Search: 307/9.1-10.7, 307/31-35, 318/139, 180/65.1, 180/65.2, 180/53.1, 180/53.5, 180/53.6, 364/423.098, 364/424.026, 364/424.045, 364/424.059, 219/202-208, 315/77-80, 315/82, 315/83, 361/154, 322/62-64
• US Class Current: 307/10.1
• CPC Class Codes: B60R 16/0315 using multiplexing techniques multiplexing for transmission of signals G08C15/00; multiplexing for electrical communication in general H04J
• CPC Class Codes: H02H 9/001 limiting speed of change of electric quantities, e.g. soft switching on or off progressive control of electronic switches for eliminating interferences H03K17/16

Abstract

An apparatus for driving electrical loads of a vehicle comprising load switches. Each of the load switches directs a start or a stop of each of the electrical loads. A memory stores a power feeding increase rate for a corresponding one of the electrical loads at a state transition of each of the load switches from an OFF to an ON state. A pair of transistors feeds power to the corresponding one of the electrical loads from a battery on receiving a load driving signal. A central process unit sends the load driving signal to the pair of transistors so that power is fed to the corresponding one of the electrical loads with a power feeding increase rate at the state transition of one of the load switch from an OFF state to an ON state. Thus, because the power fed to the electrical load gradually increases upon starting of the electrical load, AC power does not rapidly increase the power generation, and this prevents engine speed from rapidly increasing.

Claims

1. Apparatus for driving electrical loads of a vehicle, comprising:

a plurality of direction devices, each of said direction devices being provided at each of a plurality of electrical loads arranged at said vehicle, for directing an ON/OFF state of a corresponding one of said electrical loads;

storage apparatus for storing a preset power feeding increase rate for each of said electrical loads when a corresponding direction devices indicates a state transition from an OFF state to an ON state;

a plurality of drive devices, each of said driving devices being provided at each of said electrical loads, for feeding power to a corresponding one of said electrical loads and for changing an amount of power fed to said corresponding electrical load from a power source; and

a control apparatus for checking a switching state of said direction devices provided for each of said electrical loads, and, when said control apparatus has judged that at least one of said direction devices has indicated said state transition, for sending a control signal to a corresponding one of said drive devices such that power is fed to a corresponding one of said electrical loads from said power source in accordance with the preset power feeding increase rate stored in said storage apparatus.

2. Apparatus according to claim 1, wherein said storage apparatus stores a minimum power feeding ratio preset and used for each of said electrical loads, which is kept even during an OFF state of a corresponding one of said direction devices, and said control apparatus sends a control signal to a corresponding one of said drive device such that power is fed to one of said electrical loads from said power source, of which stopping is directed by a corresponding one of said direction devices, with a minimum power feeding ratio preset and stored in said storage apparatus, according to said electrical load.

3. Apparatus according to claim 1, further comprising an engine state detector for detecting an operational state of an engine of said vehicle, wherein said storage apparatus stores a power feeding increase rate preset and used for each of said electrical loads, according to each of predetermined operational states of said engine, and said control apparatus checks a switching state of each of said direction devices, and, if said control apparatus judges that at least one of said direction devices has indicated said state transition, sends a control signal to a corresponding one of said drive devices such that power is fed to a corresponding one of said electrical loads from said power source, with a power feeding increase rate preset and stored in said storage apparatus, according to said corresponding electrical load and said operational state of said engine detected by said engine state detector.

4. Apparatus according to claim 3, wherein said engine state detector includes an engine starting state detector for detecting whether said engine is at a stating state, said storage apparatus stores data indicating whether power is to be fed to each of said electrical loads, depending on functional importance of a corresponding one of said electrical loads, when a corresponding one of said direction devices directs driving of a corresponding one of said electrical loads, at said starting state of said engine, and said control apparatus determines whether power is to be fed to one of said electrical loads, of which driving is directed by a corresponding one of said direction devices at said starting state of said engine, by referring to said data stored in said storage apparatus, and sends a control signal to a corresponding one of said drive devices such that power feeding to said electrical load is stopped if said control apparatus determines not to feed power to said electrical load, and power feeding to said electrical load is continued if said control apparatus determines to feed power to said electrical load.

5. Apparatus according to claim 3, wherein said engine state detector includes an accelerator operating amount detector for detecting an operation amount of an accelerator pedal operated by an operator, said storage apparatus stores a power feeding decrease rate preset and used for each of said electrical loads if an acceleration required by an operator exceeds a predetermined value, and said control apparatus estimates said acceleration required by an operator based on said operation amount of said accelerator pedal detected by said accelerator operating amount detector, and sends a control signal to a corresponding one of said drive devices such that power is fed to one of said plurality of electrical loads, of which driving is directed by a corresponding one of said direction devices, with a power feeding decrease rate preset and stored in said storage apparatus, according to said electrical load.

6. Apparatus according to claim 1, further comprising a fuel amount detector for detecting a residual fuel amount left in a fuel tank of said vehicle, wherein said storage apparatus stores a power feeding decrease rate preset and used for each of said electrical loads when said residual fuel amount is less than a predetermined value, and said control apparatus sends a control signal to a corresponding one of said drive devices such that power is fed to one of said electrical loads, of which driving is directed by a corresponding one of said direction devices, with a power feeding decrease rate preset and stored in said storage apparatus, according to said electrical load, if said residual fuel amount detected by said fuel amount detector is less than said predetermined value.