JPH09105762A - Cross coil type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cross coil type display device capable of performing more detailed failure diagnosis. SOLUTION: In the cross coil type display device having a cross coil (42b, 43b,...) formed out of a coil pair wound mutually crossing, current supplying means (21c, 25,..., 28) for supplying a current to the cross coil, and instructing means (42a, 43a,...) rotated according to the magnetic field generated by the cross coils by the current from the current supplying means to give an instruction according to a display quantity, this device has a mode switching means (21a) for switching the operation mode of the device to display mode and diagnostic mode, voltage signal gaining means (25e, 25j,...) for gaining a voltage signal from the end part of the cross soil, and an abnormality judging means (21b) for judging the abnormality of at least either one of the current supplying means and the cross coil on the basis of the voltage signal gained by the voltage signal gaining means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross-coil type display device mounted on a vehicle such as an automobile and driving a pointer by a magnetic field generated by the cross-coil to display information such as traveling speed and engine speed. In particular, the present invention relates to a device having an abnormality determining means for determining an abnormality of a driver or a cross coil for driving the display device.

[0002]

2. Description of the Related Art Conventionally, as a cross-coil type display device provided with an abnormality judging means for judging an abnormality of a driver or a cross coil for driving a display device, for example, an actual fair 6-
There is a device described in Japanese Patent No. 48348 (hereinafter referred to as a conventional device).

This conventional device will be described below with reference to the block diagram of FIG. In the figure, 100 is a cross coil type display device. This cross coil type display device 1
00 is an input unit 101, a control unit 102, and a display unit 10.
3 are schematically constituted.

The input section 101 is constructed as a mechanism for inputting various signals, and has an address decoder 101a to which input terminals A _{0 to} A ₄ are connected and a clock input terminal 101.
b and an AND gate 101c. A start signal for meter diagnosis is input from the input terminals A _{0 to} A ₄ , and the address decoder 101a outputs the start signal as a selection signal b to the AND gate 101c. Also,
The clock signal CK is input to the AND gate 101c via the clock input terminal 101b. The AND gate 101c operates when the clock signal CK is input while the selection signal b is being output.
Is output.

The control unit 102 is constructed as a mechanism for generating a control signal for the display unit 103, and has a CPU 10
2a, an EEPROM 102b, and drivers 102c to 102e. The CPU 102a shifts to the abnormality determination mode when the activation signal a is input from the AND gate 101c of the input unit 101. When the CPU 102a shifts to the abnormality determination mode, the CPU 102a generates a drive signal (hereinafter, referred to as an adjustment signal) for performing the instruction adjustment based on the instruction adjustment data held in the EEPROM 102b, and the driver 10 outputs the adjustment signal.
2c to 102e. Then, the driver 102
c to 102e generate drive signals corresponding to the adjustment signals based on the adjustment signals.

The display unit 103 is a mechanism for displaying various information by a pointer, and is a so-called cross-coil type meter (cross-coil meter) for rotating and driving the pointer by a magnetic field from the cross-coil to an indicated angle according to the display amount. It is configured. This cross coil meter includes a plurality of cross coil meters 103a to 1a provided for each display type such as the traveling speed of the vehicle, the engine speed, and the remaining fuel.
03c. Then, by supplying drive signals from the drivers 102c to 102e corresponding to these cross coil meters 103a to 103c, these cross coil meters 103a to 10e are supplied.
A cross coil (not shown) of 3c generates a magnetic field and rotationally drives the pointer up to an indicated angle according to the display amount.

In the conventional cross-coil type display device having such a configuration, the start signal b for meter diagnosis from the address decoder 101a (input terminals A _{0 to} A ₄ ) and the clock signal CK from the clock input terminal 101b are provided. When both are output, the start signal a is output.
Is output to shift to the abnormality determination mode. Then, the CPU 102a outputs E in this abnormality determination mode.
A drive signal corresponding to the instruction adjustment data held in the EPROM 102b is sent to the drivers 102c to 102e.

The drivers 102c to 102e are CPUs.
Based on the drive signal from 102a, the corresponding cross coil meters 103a to 103c are driven in a predetermined sweep time from the minimum designated angle to the maximum designated angle. And
By observing the operating state of the pointer,
The normal operation of the drivers 102c to 102e and the cross coil meters 103a to 103c is diagnosed.

[0009]

In the conventional device described above, the device is diagnosed by driving the pointer in its entire movement range. Therefore, when the device is abnormal, It was not possible to make a more detailed diagnosis as to whether the cause of the abnormality was in the cross coil or in the driver. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cross-coil type display device capable of performing more detailed diagnosis.

[0010]

In order to solve the above problems, a cross coil type display device made according to the present invention is
As shown in the basic configuration diagram of FIG. 1, cross coils (42b, 43b, composed of coil pairs wound to cross each other,
...) and the cross coil (42b, 43b, ...)
Current supply means (21c, 25A, 25
B, ..., And the current supply means (21c, 25A, 2)
5B, ...) by the current from the cross coil (42
(b, 43b, ...) Indicated means (42a, 42a, 43b, ...) Rotated and driven in accordance with the magnetic field generated to give an instruction according to the display amount.
43a, ...,) in the cross coil type display device, a mode switching means (21a) for switching the operation mode of the device between the display mode and the diagnostic mode, and the cross coil (42b) operating in the diagnostic mode. , 43b, ...
Based on the voltage signal acquisition means (25e, 25j, ...) For acquiring the voltage signal from the end of () and the voltage signal acquired by the voltage signal acquisition means (25e, 25j, ...). The current supply means (21c, 25A, 25B, ...)
And an abnormality determining means (21b) for determining an abnormality of at least one of the cross coils (42b, 43b, ...). (Claim 1)

The voltage signal acquisition means (25e, 2e,
5j, ..., The cross coils (42b, 43b,
···) forming coils (42b1, 42b2, ···)
Of the current supply means (21c, 25)
A, 25B, ... Are the cross coils (42b, 4).
3b, ..., The coils (42b1, 42b2,
...) connected to one end of the connection terminal, a first state in which a positive voltage is applied to the connection terminal, a second state in which the connection terminal is grounded, and a third state in which the connection terminal is opened State switching means (25A, ...) And the coils (42b1, 4b)
Second state switching means (25B, ...) Connected to the other end of 2b2 ,.
And the first and second state switching means (25A, 25
., And a control means (21c) for sending a control signal for controlling the operation thereof, and the abnormality determination means (21b) is a current supply means (21c, 25A, 25).
B, ...,) The state switching means (25A, 2
5B, ...,) connected to the voltage signal acquisition means (25
e), 25j, ...) Based on the voltage signal from the voltage signal acquisition means (25e, 25j ,. It is characterized that it is determined that there is an abnormality in the state switching means (25A, 25B, ...). (Claim 2)

The voltage signal acquisition means (25e, 2
5j, ..., The cross coils (42b, 43b,
···) forming coils (42b1, 42b2, ···)
Connected to the other end to obtain the voltage signal at the other end, and the current supply means (21c, 25A, 25B, ...) Form the cross coil (42b, 43b, ...). A first state in which a positive voltage is applied to the connection end, a second state in which the connection end is grounded, and a third state in which the connection end is opened are connected to one end of the coils (42b1, 42b2, ...). First state switching means (25A, ...) For switching to the state of
Second state switching means (25B, ...) Connected to the other end of the coils (42b1, 42b2, ...) For switching the first to third states, and the first and second states. 2) state switching means (25A, 25B, ...) And a control means (21c) for sending a control signal for controlling the operation thereof, and the abnormality determination means (21b) includes the coil ( 42
b1, 42b2, ...) One state switching means (25A, 25B, ...) Connected to one end of the positive voltage is applied to the one end and the other state is connected to the other end. When the other end is opened by the switching means (25A, 25B, ...), the voltage signal acquisition means (25
, 25j, ...) does not reach a predetermined voltage value defined by the positive voltage, it is determined that the coil (42b1, 42b2, ...) Has an abnormality. Is characterized by. (Claim 3)

Further, the voltage signal acquisition means (25e, 2e,
5j, ..., The cross coils (42b, 43b,
···) forming coils (42b1, 42b2, ···)
Of the current supply means (21c, 25).
A, 25B, ... Are the cross coils (42b, 4).
3b, ..., The coils (42b1, 42b2,
...) connected to one end of the connection terminal, a first state in which a positive voltage is applied to the connection terminal, a second state in which the connection terminal is grounded, and a third state in which the connection terminal is opened State switching means (25A, ...) And the coils (42b1, 4b)
Second state switching means (25B, ...) Connected to the other end of 2b2 ,.
And the first and second state switching means (25A, 25
B), ...,), and a control means (21c) for sending a control signal for controlling the operation thereof, and the abnormality determination means (21b) has the state switching means (25A, 25B, ...
..) when determining an abnormality, voltage signal acquisition means (25e, 25j, ...) Connected to the state switching means (25A, 25B, ...) To be determined by the current supply means.
.) Based on the voltage signal from the state switching means (25A, 2A,
5B, ...) is judged, and when it is judged that the cross coil (42b, 43b, ...) Is abnormal, the state switching means (25A, 25B, .. To the other end of the coil (42b1, 42b2, ...) With a positive potential applied to the other end of the coil (42b1, 42b2, ...) And a voltage signal acquisition means (25e, 25j ,.
・) Based on the voltage signal from
3b, ...) Is configured to determine an abnormality. (Claim 4)

Further, a display means (41) for displaying character information in the display mode is provided, and when the apparatus is in the diagnostic mode, the abnormality determination means (21) is displayed on the display means (41).
It is characterized in that the diagnosis result according to b) is displayed. (Claim 5)

In the structure of claim 1, the voltage signal acquisition means (25e, 25j, ...) Is a cross coil (42).
b, 43b, ...
c, 25A, 25B, ...) and cross coil (42b,
43b, ...,) The voltage signal is acquired from the contact point, and the abnormality determination means (21b) is used as the voltage signal acquisition means (25e, 25j,
..) based on the voltage signal acquired by the current supply means (21c, 25A, 25B, ...) And the cross coils (42b, 43b, .. .

That is, since the abnormality of the current supply means and the cross coil is determined based on the voltage state of the contact portion of the current supply means and the cross coil, more detailed determination can be performed.

In the structure of claim 2, the voltage signal acquisition means (25e, 25j, ...) Is connected to both ends of the cross coil coils (42b1, 42b2 ,. Get the voltage signal of. Further, current supply means (21c, 25A, 25B, ...) Is connected to both ends of the coils (42b1, 42b2, ...) And the state of the connection ends is the first state (positive voltage application). State), second state (grounded state), third state (open state) first
And second state switching means (25A, 25B, ...) And
Control means (21) for sending a control signal for controlling the operation
c), the current is supplied to the coils (42b1, 42b2, ...) By appropriately switching the state of each connection end.

The abnormality determining means (21b) is connected to the state switching means (25A, 25B, ...) To be determined, and the voltage signal acquiring means (25e, 25j, ...) Is connected.
When this voltage signal is different from the voltage level in the normal operation, it is determined that the state switching means (25A, 25B, ...) As the determination target has an abnormality based on the voltage signal from.

That is, since the output voltage of the means for applying the voltage to the coil (state switching means) is acquired, it is possible to determine the abnormality of the voltage applying means.

In the structure of claim 3, the voltage signal acquiring means (25e, 25j, ...) Is connected to at least the other end of the cross coil coils (42b1, 42b2 ,. Get the voltage signal of the edge. Further, current supply means (21c, 25A, 25B, ...) Is connected to both ends of the coils (42b1, 42b2, ...) And the state of the connection ends is the first state (positive voltage application). Condition), second
State (grounding state) and third state (opening state) of the first and second state switching means (25A, 25B, ...)
And a control means (21c) for sending a control signal for controlling the operation of the coils (42b1, 42b2, ...) By appropriately switching the state of each connection end.
To supply current.

The abnormality determining means (21b) is provided with a voltage signal acquiring means (25e) when a positive voltage is applied to one end of the coils (42b1, 42b2, ...) And the other end is opened. , 25j, ...,), and when the voltage signal does not reach a predetermined voltage level, the coil (42b1, 42b2, ...) Has an abnormality such as a disconnection. judge.

That is, since the voltage at the other end of the coil is obtained when the predetermined voltage is applied to the one end of the coil, an abnormality such as disconnection of the coil can be determined.

In the structure of claim 4, the voltage signal acquiring means (25e, 25j, ...) Is connected to both ends of the cross coil coils (42b1, 42b2 ,. Get the voltage signal of. Further, current supply means (21c, 25A, 25B, ...) Is connected to both ends of the coils (42b1, 42b2, ...) And the state of the connection ends is the first state (positive voltage application). State), second state (grounded state), third state (open state) first
And second state switching means (25A, 25B, ...) And
Control means (21) for sending a control signal for controlling the operation
c), the current is supplied to the coils (42b1, 42b2, ...) By appropriately switching the state of each connection end.

Then, the abnormality judging means (21b) is a state switching means (25A, 25A) to be judged by the current supplying means.
B ....) connected to the voltage signal acquisition means (25e,
..) is determined based on the voltage signal from the coil 25j, ..., And a coil (42b1) in which a positive potential is applied and the other end is opened, is determined. , 42b2, ...) Connected to the other end of the cross coil (42b, 43b, ...) Based on the voltage signal from the voltage signal acquisition means (25e, 25j ,. To judge.

That is, when the abnormality of the voltage applying means is determined, the output voltage of the means for applying the voltage to the coil (state switching means) is acquired, and when the abnormality of the cross coil such as disconnection is determined, one end of the coil is acquired. Since the voltage at the other end is obtained when the predetermined voltage is applied to, it is possible to detect both an abnormality in the voltage applying means and an abnormality in the cross coil.

In the structure of claim 5, the display means (41) displays character information in the display mode,
In the display diagnostic mode, the abnormality determining means (21b)
Display the diagnostic result by.

That is, since the display means is used for both the normal display and the display of the diagnostic result, the device structure can be simplified.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing the configuration of a specific example according to the present invention. In FIG. 1, 1 is an input unit for inputting various information and the like, 2 is a control unit for controlling the apparatus, 3 is a nonvolatile memory in which information referred to by the control unit 2 is stored (hereinafter,
NVM3) 4 is a display unit for displaying various information about the vehicle.

The input section 1 is provided as a mechanism for inputting various information and the like as described above, and is roughly composed of a power source-related terminal group, various sensor-related terminal groups, and operation switches. The above-mentioned power supply-related terminal group includes a power supply terminal (BATT +) 11 to which a power supply voltage from a battery (not shown) is supplied, and a ground potential GND.
Terminals 12 and are provided. And this power supply terminal 1
The power supply voltage supplied via 1 is adjusted to a predetermined voltage via the regulator 11a, and the control unit 2 (CPU described later)
21).

As a terminal group related to various sensors,
A travel pulse from an ignition terminal 13 to which an ignition signal from an ignition switch (not shown) that controls the start / stop of the engine is input, and a travel sensor (not shown) that outputs a travel pulse every time the vehicle travels a unit distance. An SP terminal 14 to which a signal is input, and a TA terminal 15 to which a pulse signal (engine rotation signal) proportional to the engine speed from an ignition coil (not shown) configured as one component of the engine ignition system is input , A FUEL terminal 16 to which a fuel detection signal from a fuel sensor (not shown) provided in a fuel tank for detecting the remaining amount of fuel such as gasoline is input, and cooling water circulating in a radiator (not shown) for cooling the engine TEM to which the water temperature signal from the water temperature sensor (not shown) that detects the temperature of the
P terminal 17 is provided.

The ignition terminal 13, the SP terminal 14, and the TA terminal 15 are provided with corresponding interface (I / F) circuits 13a to 15a, respectively, and the ignition signal is transmitted via these I / F circuits 13a to 15a. The traveling pulse signal and the engine rotation signal are input to the control unit 2. In addition, the FUEL terminal 16 and the TEM
The fuel detection signal and the water temperature signal from the P terminal 17 are input to the control unit 2 via the voltage dividing circuit 18.

As the operation switch, the traveling distance information of the vehicle is displayed as the total traveling distance (ODD) and the section traveling distance (TR).
Display changeover switch 19 operated when changing to IP)
A and a failure diagnosis switch 19B operated when executing the failure diagnosis operation are provided.

The control unit 2 comprises a CPU 21, a ROM 22 and a RAM 23. The CPU 21 functions as a so-called central control device that executes a predetermined processing operation according to an operation program, and receives various signals and power supply voltage from the input unit 1 described above. This CPU
The driver 21 is provided with a plurality of drivers 24 to 28 provided corresponding to each display mechanism of the display unit 4 which will be described later. The ROM 22 is configured as a storage unit that stores an operation program of the CPU 21 and a predetermined value given in advance, and the content stored in the ROM 22 is C when the apparatus is operating.
Referenced by the PU 21. RAM23 is CPU21
Is configured as a readable / writable storage means for temporarily holding necessary information during the operation of.

The NVM 3 is constituted as a storage means for storing various table information and the like, and in a partial area thereof, swing angle information defining the relationship between the swing angle of the pointer and the control amount of the control signal sent by the CPU 21, Various information such as mileage information indicating the mileage of the vehicle is stored.

The display unit 4 mainly displays the total traveling distance (OD) of the vehicle.
D) or a liquid crystal display (L) that displays information about the mileage of the vehicle, such as the trip distance
CD) 41, a speedometer 42 that displays vehicle speed information, a tachometer 43 that displays the number of revolutions of the engine, and a fuel gauge 44 that displays the remaining amount of fuel.
And a water temperature gauge 45 for displaying the temperature of the cooling water of the radiator.

Among the display mechanisms of the display unit 4,
The speedometer 42, the tachometer 43, the fuel gauge 44, and the water temperature gauge 45 have pointers 4 which the display mechanism has.
It is configured as a cross-coil pointer-type display device that performs display by rotating 2a to 45a by the magnetic field from the cross coils 42b to 45b.

Further, each of these display mechanisms (LCD 41 to water temperature gauge 45) receives travel distance information, speed information, engine speed information in response to a drive signal input via the corresponding driver 24 to 28 of the control unit 2. Is displayed.

That is, the LCD 41 displays information on the traveling distance of the vehicle based on the drive signal from the corresponding driver 24, and the speedometer 42 and the tachometer 43 are PWM drive signals (COS +, COS- from the corresponding drivers 25 and 26). , SIN +, SIN−) based on the vehicle running speed and engine speed are displayed, and the fuel gauge 44 and the water temperature gauge 45 receive the PWM drive signals (SIN +, SIN +, SIN +,
Based on SIN-), information regarding the remaining amount of fuel and the temperature of cooling water is displayed.

Next, with reference to FIG. 3, the structure of the main part of this display device will be described. This figure is a block diagram for explaining the configuration of the peripheral mechanism centering on the above-mentioned driver. In particular, the driver 2 that supplies a drive signal to the speedometer 42.
It is the figure shown about 5. In addition, other drivers, that is, the drivers 26 to 28, the tachometer 43 and the fuel gauge 44 corresponding to the drivers 26 to 28, respectively.
Since the water temperature gauge 45 and the water temperature gauge 45 have the same configuration as the driver 25 and the speedometer 42, the driver 25 and the corresponding speedometer 42 will be described here and will be replaced with the description of other drivers and meters. To do.

As shown in the figure, the driver 25 has four
It has two terminals COS +, COS-, SIN + and SIN-. Then, these terminals COS +, COS
−, SIN +, and SIN− are connected to the cross coil 42b of the speedometer 42. More specifically, the terminal COS + is connected to one end side of the first coil 42b1 that constitutes the cross coil 42b, and the output terminal COS− is also connected.
Is connected to the other end of the first coil 42b1. Similarly, the terminal SIN + is connected to one end side of the second coil 42b2 forming the cross coil 42b, and the terminal SIN−.
Is connected to the other end side. Since the resistance values of the first coil 42b1 and the second coil 42b2 are about 100Ω, the coils 42b1 and 42b2 act as resistances when energized.

In the driver 25, driving units 25A (terminal COS +) to 25D (terminal SIN-) are connected to these terminals COS + to SIN-. These drive units 25A to 25D function as state switching means for switching the corresponding terminals COS + to SIN- (corresponding to the ends of the cross coil 42b) to the positive voltage applied state, the grounded state, and the open state. It has the same structure.

For example, the drive unit 25A outputs a voltage signal for a period corresponding to the control signal from the CPU 21 in the P-ch.
It is composed of an output control unit 25a and an N-ch output control unit 25b, a first FET 25c, and a second FET 25d. The above-mentioned first FET 25c and second FET 25
d is connected in series complementarily between the power supply V _DD and the ground, and the P-ch output control unit 25a is connected to the gate of the first FET 25c and the N-ch output control unit 25b is connected to the gate of the second FET 25d. Each is connected.

The terminal COS + is connected to the first FE
It is drawn from the contact point of the drain of T25c and the source of the second FET 25d. Therefore, the first FET 25c
Is on and the second FET 25d is off, the terminal COS + is in a positive voltage application state, and conversely, the first FET 25c is off and the second FET 25d is on. , Terminal COS + is grounded. In addition, the first FET 25c and the second FET 25d
When both are turned off, the terminal COS + is opened.

The drive unit 25B includes a P-ch output control unit 25f and an N-ch output control unit 25g, and a first FE.
It is composed of T25h and the second FET 25i, and these respective parts are connected in the same manner as the above-mentioned drive part 25A.

Then, the above-mentioned drive units 25A to 25D
Of the port level detection circuit 25e (driving section 25A), 2
5j (driving unit 25B), 25k (driving unit 25C), 25
m (drive unit 25D) is connected. The port level detection circuits 25e, ..., 25m are composed of Schmitt trigger inverters and resistors, as shown in FIG.
The voltage level of each terminal COS + to SIN- is detected.
That is, when the voltage level of each of the terminals COS + to SIN− (for example, point A in the port level detection circuit 25e) is lower than the specified value, the port level detection circuit 25
.., 25m outputs "1" (H level) to the CPU 21 (same point B), and outputs "0" (L level) when the value is equal to or more than the specified value.

When a signal indicating that the failure diagnosis operation is to be executed is input from the failure diagnosis switch 19B, the CPU 21 shifts to a mode for executing the failure diagnosis operation, and drives 25A to 25D of the driver 25 and other parts. Driver 26
.., 25m of the driver 25 and the port level detection circuits of the other drivers 26 to 28 (not shown). The check signal output from (not shown) is input.

Next, the operation of the specific example having the above-mentioned structure will be described with reference to the flow charts of FIGS. In this specific example, first, in step S110 of the main flowchart shown in FIG. 4, it is determined whether or not a failure diagnosis signal has been input. That is, this step S110
Then, by operating the failure diagnosis switch 19B, the CPU 21
It is determined whether or not a failure diagnosis signal has been input to.

When the failure diagnosis signal is input (Y), the process proceeds to step S120 and the failure diagnosis process is executed. On the other hand, if the failure diagnosis signal is not input (N), the process proceeds to step S130 and the LCD 4
The display content of 1 is used as character information such as mileage, and then display information such as mileage, mileage, engine speed, remaining amount of gasoline, water temperature (cooling water) is acquired in step S140, and described above in step S150. Display unit 4 (LC
By driving D41 to water temperature gauge 45), mileage information (LCD 41), travel speed information (speed meter 42), engine speed information (tachometer 43), gasoline remaining amount information (fuel gauge 44), water temperature information ( The water temperature gauge 45) is displayed.

When the failure diagnosis process of step S120 and the display process of step S150 are completed, the process proceeds to the failure diagnosis signal input determination process of step S110 again.
The series of processes described above is executed again.

Next, the failure diagnosis processing in step S120 will be described in detail. This failure diagnosis process is specifically performed by the flowchart of FIG. That is, in this failure diagnosis process, first, step S21
At 0, the process of erasing the display on the LCD 41 is executed.

Next, in step S220, the diagnostic operation for the speedometer 42 is executed. That is,
In step S220, the CPU 21 sends a control signal for executing the diagnostic operation to the control units 25A to 25D (see FIG. 3) of the driver 25 by executing the check mode process described later, and also detects the port level. The port check signal from the circuits 25e, ..., 25m is received. Then, based on the correlation between the transmitted control signal and the received port check signal, the speedometer 4
Diagnosis for 2.

In the subsequent step S230, the diagnostic operation for the tachometer 43 is executed. That is, in this step S230, the CPU 21 causes the above-mentioned step S22.
The check mode process is executed for the driver 26 as in the case of 0. Then, in step S240, the diagnosis process for the fuel gauge 44 (driver 27) is executed, and in step S250, the diagnosis process for the water temperature gauge 45 (driver 28) is executed. The diagnostic process for the fuel gauge 44 and the water temperature gauge 45 is also performed by the check mode process. However, the terminals to be controlled of the fuel gauge 44 and the water temperature gauge 45 are S terminals.
Since there are two types, IN + and SIN-, the terminals SIN + and S
This is the check mode processing for IN-.

Then, in step S260, it is determined whether or not there is an error (abnormality) in the diagnostic operation of steps S220 to S250 described above. If there is an abnormality, the process proceeds to step S270, and an error code indicating the diagnosis content is displayed on the display unit 41. If there is no abnormality, the failure diagnosis process is terminated, Return to the main flow chart. The display of the error code in step S270 is, for example, as shown in FIG.
The display is as shown in.

That is, as shown in the figure, this display is composed of information A to d indicating the type of meter and information 1 to 5 indicating the contents, and the P-ch of the drive unit 25A corresponding to the speedometer 42. "A-1" is displayed when the output control unit 25a has a failure, and "A-1" is displayed when the cross coil 42 (coils 42b1 and 42b2) is broken.
-5 ”is displayed. Also, C of the fuel gauge 44
When the OS + side N-ch output control unit (not shown) fails, "C-3" is displayed.

Next, steps S220 to S2 described above.
The check mode processing performed in the diagnostic operation 50 will be described. This check mode processing is
This is performed according to the flowchart of FIG. The check mode process includes check modes 0 (S300) to 7 (S370), and the check mode 0 (S30)
Check modes 4 (S340) to 7 (0) to 3 (S330) are processes performed by the drive units (e.g., the drive units 25A and 25B in the driver 25) corresponding to the terminals COS + and COS- of the drivers 25 to 28.
(S370) corresponds to the terminals SIN + and SIN- of the drivers 25 to 28 (for example, the driver 25
(Corresponding to the drive units 25C and 25D in).

In this process, first, check mode 0 is executed in step S300. In the check mode 0, the P-ch output control unit (corresponding to the P-ch output control unit 25a in the driver 25) on the terminal COS + side is turned OFF, that is, the L level, and the N-ch output control unit (the same N-ch output control unit). (Corresponding to part 25b) is turned on, that is, H level, and the P-ch on the terminal COS- side
Set the output control unit (corresponding to the same P-ch output control unit 25f) to O
N, N-ch output control unit (the same N-ch output control unit 2
5g) is turned off. Thereby, the terminal COS
The power supply voltage V _DD is applied to − (corresponding to point C in FIG. 3) and the terminal COS + (corresponding to point A) is grounded.

In a succeeding step S301, it is determined whether or not there is an error in the check mode 0. That is, in this step S301, the terminal COS-connected port level detection circuit (the same port level detection circuit 25
(corresponding to e), whether the voltage level of the terminal COS- is approximately the power supply voltage V _DD ,
It is determined whether the + voltage level is approximately the ground potential. If these determination conditions are satisfied (none), the process proceeds to step S310, and if these determination conditions are not satisfied (present), an error code indicating the content of the abnormality is output to the control unit in step S302. After storing in the RAM 23 of 50, it transfers to step S310.

In step S310, check mode 1 is executed. In this check mode 1, the P-ch output control unit on the terminal COS + side is turned on and the N-ch output control unit is turned on.
FF, P-ch output control unit on the terminal COS- side and N
Both -ch output control units are turned off. This allows
The power supply voltage V _DD is applied to the terminal COS +, and the terminal COS- is opened.

In a succeeding step S311, it is determined whether or not there is an error in the check mode 1. That is, in this step S311, the terminals COS + and CO
Based on the output from the S-connected port level detection circuit, it is determined whether the voltage levels of these terminals COS + and COS- are approximately the power supply voltage V _DD . Then, when these determination states are satisfied (none), step S3
If the determination state is not satisfied (Yes) in step S20, the error code indicating the content of the abnormality is stored in the RAM 23 in step S312, and then step S320 is performed.
Move to

In step S320, check mode 2 is executed. In this check mode 2, the P-ch output control unit on the terminal COS + side is turned on and the N-ch output control unit is turned on.
FF, and the P-ch output control unit on the terminal COS- side is OF
The F, N-ch output control section is turned on. As a result, the power supply voltage V _DD is applied to the terminal COS- and the terminal C
OS + becomes the grounded state.

In the following step S321, it is determined whether or not there is an error in this check mode 2. That is, in this step S321, the terminals COS + and CO
Based on the output from the port level detection circuit connected to S-, the voltage level of the terminal COS + becomes approximately ground potential,
It is determined whether the voltage level of COS- is approximately the power supply voltage V _DD . Then, when these determination states are satisfied (none), the process proceeds to step S330, and when these determination states are not satisfied (present), an error code indicating the content of the abnormality is stored in the RAM 23 in step S322. After storing, the process proceeds to step S330.

In step S330, check mode 3 is executed. In this check mode 3, the P-ch output control unit and the N-ch output control unit on the terminal COS + side are turned off.
And the P-ch output control unit on the terminal COS + side is turned ON and N
The -ch output control unit is turned off. As a result, the terminal C
The OS + is opened and the power supply voltage V _DD is applied to the terminal COS-.

In the following step S331, it is determined whether or not there is an error in this check mode 3. That is, in this step S331, the terminals COS + and CO
Based on the output from the port level detection circuit connected to S-, it is determined whether the voltage level of these terminals COS + and COS- is approximately the power supply voltage V _DD . And
If these determination conditions are satisfied (none), step S
If the determination state is not satisfied (Yes), the process proceeds to step S332, the error code indicating the content of the abnormality is stored in the RAM 23, and then step S34 is performed.
Move to 0.

Then, in step S340, the check mode 4 is executed. The check mode 4 is a process for the drive units corresponding to the terminals SIN + and SIN- of the drivers 25 to 28, and corresponds to the process of step S300 in the process of the drive units corresponding to the terminals COS + and COS- described above. Processing. That is, in step S340, the P-ch output control unit on the terminal SIN + side is turned off, the N-ch output control unit is turned on, and the P-ch output control unit on the terminal SIN- side is turned on and the N-ch output control unit is turned on. Is turned off.

Then, in the following step S341,
Check mode 4 is executed by the same processing as step S301.
Determine whether there is an error in. This step S30
If the determination condition is satisfied in 1 (none), step S35.
If the determination state is not satisfied (Yes), the error code indicating the content of the abnormality is stored in the RAM 52 in step S342 and then the process proceeds to step S350.

In step S350, check mode 5
Execute This check mode 5 is the same as step S above.
In the process corresponding to 310, the P-ch output control unit on the terminal SIN + side is turned on, the N-ch output control unit is turned off, and both the P-ch output control unit and the N-ch output control unit on the terminal SIN- side are turned on. This is a process of turning off.

Then, in the following step S351,
Whether or not there is an error in check mode 5 is determined (similar to step S311). If the determination condition is satisfied (NO) in step S351, the process proceeds to step S360, and if the determination condition is not satisfied (YES), an error code indicating the content of the abnormality is RA in step S352.
After storing in M52, the process proceeds to step S360.

In step S360, check mode 6
Execute This check mode 6 is the same as step S above.
In the process corresponding to 320, the P-ch output control unit on the terminal SIN + side is turned on, the N-ch output control unit is turned off, and the P-ch output control unit on the terminal SIN- side is turned off, N-ch.
The output control unit is turned on.

Then, in the following step S361,
Whether or not there is an error in the check mode 6 is determined (similar to step S321 above). If the determination condition is satisfied in step S361 (none), the process proceeds to step S370, and if the determination condition is not satisfied (present), an error code indicating the content of the abnormality is RA in step S362.
After storing in M52, the process proceeds to step S370.

In step S370, check mode 7
Execute This check mode 7 is the same as step S above.
In the process corresponding to 330, the P-ch output control unit and the N-ch output control unit on the terminal SIN + side are turned off, and the terminal S
The IN + side P-ch output control unit is turned on and the N-ch output control unit is turned off.

Then, in the following step S371,
Whether or not there is an error in the check mode 7 is determined (same as step S331 above). If the determination condition is satisfied (NO) in step S371, the check mode process is ended (return) as it is, and if the determination condition is not satisfied (YES), the content of the abnormality is indicated in step S372. After storing the error code in the RAM 52, the check mode process ends (returns).

As is apparent from the above description, the flowchart of the specific example and the basic configuration of the present invention have the following correspondence. That is, the mode switching means (21a) is
4 corresponds to step S110 of the flowchart, and the abnormality determination means (21b) corresponds to step S120 of the flowchart of FIG. In addition, control means (21
c) is step S31 in the flowchart of FIG.
0, S320, ..., S370.

Next, with reference to FIG. 7, an example of failure diagnosis in this example will be described. As shown in the figure, check mode 0 (terminal COS + side P-ch output control unit = OF
F, N-ch output control unit = ON, terminal COS-side P-c
When the output control unit = ON and the N-ch output control unit = OFF) are executed, the voltage (port level) of the terminal COS + detected based on the port level detection circuit on the terminal COS + side and the terminal COS− side If both the voltage (port level) of the terminal COS− detected based on the output of the port level detection circuit of “1” (H level = approximately power supply voltage V _DD ), P on the terminal COS + side is detected. −Ch output control unit is determined to be out of order.

In this mode 0, this is originally
This is because the terminal COS + outputs the H level even though it is in the grounded state (L level). And as for this factor, the terminal C
Since an abnormality in the P-ch output control unit on the OS + side is possible, it is determined here that the P-ch output control unit on the terminal COS + side is out of order.

In addition, mode 1 (terminal COS + side P-ch
Output control unit = ON, N-ch output control unit = OFF, terminal COS-side P-ch output control unit = OFF, N-ch output control unit = OFF)
When the voltage of + is “1” (H level) and the voltage of the terminal COS− is “0” (L level = approximately ground voltage), the coil between the terminals COS + and COS− (for example, in the figure It is determined that the coil 42b1) in No. 3 is broken.

In this mode 1, this is the terminal C
Since OS- is open, this terminal COS-
This is because the power supply voltage V _DD applied to the terminal COS + should appear, but this terminal COS- is at the L level. Since the cause of this may be disconnection of the coil between the terminal COS + and the terminal COS-, it is determined here as disconnection of this coil.

In the check mode 1, the voltage at the terminal COS + and the voltage at the terminal COS- are both "0".
If it is (L level), P- on the terminal COS-side
It is determined that the ch output control unit has failed. This is the terminal COS
This is because the power supply voltage V _DD (H level) applied to + should appear, but it is at the ground voltage (L level).

Then, based on the same idea, in the check mode 2, when both the voltage of the voltage terminal COS- of the terminal COS + are "1" (H level), the N-ch output control on the terminal COS- side is performed. When it is determined that the section is defective, and both the voltages of the voltage terminal COS- of the terminal COS + are "0" (L level) in the check mode 3, the P-ch output control section on the terminal COS- side. Is determined to be defective. Also, in the check modes 4 to 7, the determination is made based on the same idea.

As described above, in the check mode process, the drive unit (eg, FIG. 3) as the state switching means for applying the voltage to the coil, that is, the terminals COS + to SIN-.
Output voltage from the driving units 25A to 25D in the port level detection circuit (the same port level detection circuit 25e,
.., 25 m) and is configured to determine an abnormality such as a drive unit failure or cross coil disconnection based on the output from the port level detection circuit, so more detailed determination is performed. You can

[0080]

As is apparent from the above description, the cross coil type display device of the present invention has the following effects.
That is, since the abnormality of the current supply means and the cross coil is determined based on the voltage state of the contact portion of the current supply means and the cross coil, more detailed determination can be performed.

Further, since the output voltage of the means for applying the voltage to the coil (state switching means) is acquired,
It is possible to determine an abnormality in the voltage applying means.

Since the voltage at the other end of the coil is obtained when a predetermined voltage is applied to the one end,
Abnormalities such as coil breakage can be determined.

Further, when it is determined that the voltage applying means is abnormal, the output voltage of the means (state switching means) that applies a voltage to the coil is acquired, and when it is determined that the cross coil is abnormal such as disconnection, one end of the coil is acquired. Since the voltage at the other end is obtained when the predetermined voltage is applied to, it is possible to detect both an abnormality in the voltage applying means and an abnormality in the cross coil.

Further, since the display means is used for both the normal display and the display of the diagnostic result, the device structure can be simplified.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a basic configuration of the present invention.

FIG. 2 is a diagram showing a configuration of a specific example according to the present invention.

FIG. 3 is a diagram showing a configuration of a main part of a specific example.

FIG. 4 is a flowchart illustrating the main operation of a specific example.

FIG. 5 is a flowchart illustrating a failure diagnosis process.

FIG. 6 is a flowchart illustrating check mode processing.

FIG. 7 is a diagram illustrating an example of failure diagnosis.

FIG. 8 is a diagram showing a display example of a diagnosis result.

FIG. 9 is a diagram illustrating a conventional device.

[Explanation of symbols]

 1 Input part 19B Failure diagnosis switch 2 Control part 21 CPU 22 ROM 23 RAM 24 Driver (for LCD) 25-28 Driver (for cross coil meter) 25A-25D Drive part 25a, 25f P-ch output control part 25b, 25g N -Ch output control unit 25e, 25j Port level detection circuit 4 Display unit 41 Liquid crystal display (LCD) 42 Speedometer 42a Pointer 42b Cross coil 43 Tachometer 43a Pointer 43b Cross coil 44 Fuel gauge 44a Pointer 44b Cross coil 45 Water temperature gauge 45a Pointer 45b Cross coil

Claims (5)

[Claims] 1. A cross coil composed of a pair of coils wound so as to cross each other, a current supply means for supplying a current to the cross coil, and a magnetic field generated by the cross coil by a current from the current supply means. Following the rotation drive,
In a cross-coil type display device having an instruction means for giving an instruction according to the display amount, a mode switching means for switching the operation mode of the device between a display mode and a diagnostic mode; A voltage signal acquisition unit that acquires a voltage signal from the end, and an abnormality determination unit that determines an abnormality of at least one of the current supply unit and the cross coil based on the voltage signal acquired by the voltage signal acquisition unit, A cross coil type display device characterized in that 2. The voltage signal acquisition means is connected to both one end and the other end of a coil forming the cross coil, and acquires the voltage signal at each connection end, and the current supply means is the cross coil. Is connected to one end of a coil that constitutes a coil, and a first state in which a positive voltage is applied to the connection end, a second state in which the connection end is grounded, and a third state in which the connection end is opened are switched to a first state. The state switching means is connected to the other end of the coil, and the first to third
The second state switching means and the control means for sending a control signal for controlling the operation to the first and second state switching means. When the voltage signal from the voltage signal acquisition means is different from the voltage level in the normal operation based on the voltage signal from the voltage signal acquisition means connected to the state switching means side that is the determination target of the means, it becomes the determination target. The cross coil type display device according to claim 1, wherein it is determined that the state switching means has an abnormality. 3. The voltage signal acquisition means is connected to the other end of the coil forming the cross coil to acquire the voltage signal of the other end, and the current supply means is one end of the coil forming the cross coil. First state switching means connected to a first state for applying a positive voltage to the connection end, a second state for grounding the connection end, and a third state for opening the connection end; Is connected to the other end of the coil, and the first to third
The second state switching means and the control means for sending a control signal for controlling the operation to the first and second state switching means. When the positive voltage is applied to the one end by one state switching means connected to one end of the other end and the other end is opened by the other state switching means connected to the other end, the voltage signal acquisition The cross-coil type display device according to claim 1, wherein when the voltage signal from the means does not reach a predetermined voltage value defined by the positive voltage, it is determined that the coil has an abnormality. 4. The voltage signal acquisition means is connected to both one end and the other end of a coil forming the cross coil, and acquires the voltage signal from each connection end, and the current supply means is the cross coil. Is connected to one end of a coil that constitutes a coil, and a first state in which a positive voltage is applied to the connection end, a second state in which the connection end is grounded, and a third state in which the connection end is opened are switched to a first state. The state switching means is connected to the other end of the coil, and the first to third
The second state switching means and the control means for sending a control signal for controlling the operation to the first and second state switching means. When the abnormality of the switching means is determined, the abnormality of the state switching means is determined based on the voltage signal from the voltage signal acquisition means connected to the side of the state switching means to be determined by the current supply means, and the abnormality of the cross coil is detected. When determining that the cross coil is based on the voltage signal from the voltage signal acquisition unit connected to the other end of the coil, the positive potential is applied to one end by the state switching unit and the other end is opened. The cross-coil type display device according to claim 1, wherein the cross-coil type display device is configured to determine an abnormality with respect to. 5. A display means for displaying character information in the display mode is provided, and when the device is in the diagnosis mode, the display means displays the diagnosis result by the abnormality determination means. Item 5. The cross coil type display device according to item 1, 2, 3 or 4.