JP2879871B2 - Vehicle operation recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular operation recording device provided with vehicle traveling data storage means, external input / output means, and analysis means.

[0002]

2. Description of the Related Art With respect to such an apparatus, the present applicant has filed Japanese Utility Model Application No.
No. 144418 and Japanese Utility Model Application No. Hei 3-15332.

[0003] In these devices, at the end of operation, an external input / output means is connected to the vehicle travel data storage means, the operation data recorded in the storage means is transmitted, and the analysis means transmits the vehicle travel data from the external input / output means. It reads and analyzes it.

[0004] The vehicle running data storage means stores running data such as vehicle speed and engine speed. However, in performing vehicle operation management such as driver time management and vehicle management, a so-called vehicle stop state ( Key-off) is also an important factor.

[0005]

However, energizing the vehicle running data storage means provided with a central processing unit (CPU) at the time of key-off requires a problem such as battery consumption.
Generally, data processing at the time of key-off is not performed. Therefore, there is a problem in performing vehicle operation management.

On the other hand, as a method of measuring only the stop time, there is a method of using a real-time clock to measure the current consumption during key-off while minimizing the current consumption.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an operation recording apparatus for a vehicle which can measure the key-off time while suppressing the power consumption of the vehicle traveling data storage means.

[0008]

According to the present invention, there is provided a vehicle operation recording apparatus comprising a vehicle traveling data storage means, an external input / output means, and an analysis means, wherein the storage means comprises a central processing unit. Operating mode switching means for switching the operation of the central processing unit between the normal mode and the low power consumption mode; and calculating means for calculating a key-off time from the number of times of switching of the operating mode switching means.

[0009] The operation mode switching means and the arithmetic means include:
It is preferably provided in the processing program of the central processing unit.

[0010]

In the vehicle operation recording apparatus configured as described above, the power consumption mode is adopted at the time of key-off to suppress power consumption. Moreover, the key-off time is accurately calculated from the number of times of mode switching without providing a real-time clock.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a vehicle operation recording device includes a vehicle running data storage means, ie, an on-board unit generally designated by reference numeral 1 and an external input / output means selectively connected to the on-board unit 1, ie, a known electronic notebook. 10 and analysis means provided in an office (not shown), that is, a personal computer.

The on-vehicle device 1 is composed of, for example, an 8-bit microcomputer, and has a central processing unit (CPU).
2, ROM (ROM) 3 and RAM (RAM) 4 are provided. An ignition key switch 10, a speed sensor 11, and an engine rotation sensor 12 are connected to the central processing unit 2 via an interface 5, and a communication interface 6 is connected to the central processing unit 2, the ROM 3, and the ram 4.
The electronic notebook 20 is selectively connected via the.

The vehicle-mounted device 1 is provided with a power supply circuit 7 and a battery 13 is connected thereto. Referring also to FIG.
The power supply circuit 7 includes a constant power supply circuit 8 and a key-linked power supply circuit 9.
Are provided. A battery 13 is connected to the constant power supply circuit 8 and is connected to the central processing unit 2 and the ram 4. On the other hand, a key switch 10 is connected to the key-linked power supply circuit 9, and is connected to the central processing unit 2, ROM 3, RAM 4, and communication interface 6. The vehicle-mounted device 1 has a low power consumption mode called a sleep mode. This is a function that, even if the operation of the central processing unit 2 is stopped, retains an internal register and does not stop peripheral functions such as a counter, but returns to a normal operation by interruption or reset.

Next, the mode of control will be described.

In FIG. 3, when the key switch 10 is turned on, the central processing unit 2 clears the setting conditions of input / output ports and the like and the work area of the ram 4 (step S1), and reads the key-off count value from the ram 4. (Step S
2) Convert the count value into time (step S)
3) and store it in the data area of RAM 4 (step S
4) Perform normal measurement processing (step S5). FIG.
, When the key switch 10 is turned off, the central processing unit 2 stores the measurement data in the ram 4 (step S1).
0), the key-off time count value is cleared (step S11), the next interrupt time t (FIG. 6) is set (step S12), and the central processing unit 2 shifts to the sleep mode, that is, the low power consumption mode. 6, the central processing unit 2 is periodically returned to the normal operation (wake-up) WU by the preset fixed time (T) interrupt setting, so that the stop time is counted (step S1).
3) End the control. In FIG. 6, a characteristic C is a free-run counter of the central processing unit 2, ES is a small value of power consumption in the low power consumption mode, EB is a large value in the normal mode,
EM is a medium value at the time of wake-up WU.

In FIG. 5, when there is a time interruption, the central processing unit 2 determines whether or not the key switch 10 is ON (step S20). If NO, the key-off time is counted (step S21), the next interrupt time is set (step S22), the central processing unit 2 is shifted to the low power consumption mode (step S23), and the control is ended. If step S20 is YES, that is, if the key switch 10 is ON, the process proceeds to a time interruption process at the time of key ON, that is, the flow of FIG. 2 (step S24).
End control.

[0018]

Since the present invention is configured as described above, the key-off time can be measured with reduced power consumption without providing a real-time clock or the like in the vehicle-mounted device.

Further, the size of the apparatus can be reduced and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a control block diagram showing one embodiment of the present invention.

FIG. 2 illustrates a power supply circuit.

FIG. 3 is a control flowchart at the time of key-on.

FIG. 4 is a control flowchart at the time of key-off.

FIG. 5 is a control flowchart at the time of interruption.

FIG. 6 is a control timing chart.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Onboard equipment 2 ... Central processing unit 3 ... Rom 4 ... Ram 5 ... Interface 6 ... Communication interface 7 ... Power supply circuit 8 ... Constant power supply circuit 9 ...・ Key-linked power supply circuit 10 ・ ・ ・ Key switch 11 ・ ・ ・ Speed sensor 12 ・ ・ ・ Engine rotation sensor 13 ・ ・ ・ Battery 20 ・ ・ ・ Electronic organizer

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁶ , DB name) G07C 1/00-15/00 G06F 1/00 G06F 15/02 G08G 1/00

Claims (1)

(57) [Claims] 1. A vehicular operation recording device comprising a vehicle running data storage means, an external input / output means, and an analysis means, wherein the storage means comprises a central processing unit, and the operation of the central processing unit is performed in a normal mode. An operation mode switching device for switching between an operation mode switching mode and a low power consumption mode, and a calculation device for calculating a key-off time from the number of times of switching of the operation mode switching device, are provided.