JPH0131556Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a turn signal for a vehicle and a hazard control device having a turn signal lamp disconnection detection function.

[Prior Art] For example, in a car, a left turn instruction and a right turn instruction (turn At the same time, the emergency state is displayed (hazard operation) by flashing the turn signal lamps at the same time in response to turning on the hazard switch. In this case, when a turn signal lamp is disconnected, this is detected, and when a right turn or left turn is instructed, for example, the blinking cycle of the turn signal lamp and the blinking cycle of the turn signal indicator lamp provided on the instrument panel are adjusted. The system is configured to notify that the turn signal lamp has been disconnected by making the turn signal lamp turn on quickly (or turning on continuously).

Conventionally, a means for detecting disconnection of a turn signal lamp has been to detect a decrease in load current due to disconnection of a turn signal lamp. Specifically, a current detection resistor is interposed in series in the common conduction path of the turn signal lamps for left and right turns, and the voltage drop across the current detection resistor when the turn signal lamp is energized (i.e., the voltage drop in the current detection resistor is (equivalent to the load current) becomes less than a predetermined value, this is determined to be a disconnection occurrence. However, in such a conventional configuration, when a hazard operation is being performed in which the turn signal lamp disconnection alarm is not required, in other words, both the left turn and right turn turn signal lamps are energized at the same time and the load current does not reach the turn signal operation. Even when the load current flows twice as much as normal, the load current flows through the current detection resistor, which causes the problem that the amount of heat generated by the current detection resistor becomes extremely large. There was a risk that parts would melt.

[Purpose of the invention] The present invention has been made in view of the above circumstances, and its purpose is to use a current detection resistor installed to allow the load current of the turn signal lamp to flow, that is, to detect disconnection of the turn signal lamp. It is an object of the present invention to provide a turn signal and a hazard control device for a vehicle, which are effective in suppressing unnecessary heat generation in a current detection resistor provided to cause a voltage drop in accordance with the load current.

[Summary of the invention] In order to achieve the above object, the present invention provides a first power line connected to the battery via an ignition switch, and a second power line directly connected to the battery. line, and when the hazard switch is off, the first power line is connected to the common energizing path of the left turn and right turn turn signal lamps, and when the hazard switch is on, the second power line is connected to the common energizing path. A changeover switch connected to the electric circuit is provided, and a current detection resistor for detecting disconnection of the turn signal lamp is interposed in series with the first power supply line. This prevents load current from flowing through the current detection resistor.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 1, 1 is a battery whose negative terminal side is grounded, and whose positive terminal side is connected to a first power line 2 via an ignition switch 3, and a second power line 4.
directly connected to. 5 and 5 are turn signal lamps for indicating a left turn (hereinafter abbreviated as a left turn lamp), 6 and 6 are turn signal lamps for indicating a right turn (hereinafter abbreviated as a right turn lamp), and these left turn lamp 5 and right turn lamp 6 has one end grounded, and the other end connected to the common energizing path 9 through the normally open relay switches 7a and 8a of the blinking relays 7 and 8, respectively. has been done. 10 is a power supply switching relay which is a changeover switch, and the relay switch 1
The normally closed side contacts (c-b) of the relay switch 10a are interposed between the first power supply line 2 and the common energizing path 9, and the normally open side contacts (c-a) of the relay switch 10a are interposed between the first power supply line 2 and the common energized path 9. It is interposed between the power supply line 4 of No. 2 and the common energization path 9. Reference numeral 11 denotes a current detection resistor, which is interposed in series with the first power supply line 2. 12 is a control circuit which is a detection means and includes a microcomputer, and its output terminal
The switching command signal S ₁ is continuously output from Q ₁ , and the drive command signal S ₂ is output from output terminals Q ₂ and Q ₃ respectively.
and _S3 are output intermittently. 1
3 is each command signal output from this control circuit 12
Each of the relays 7, 8, 10 based on S ₁ , S ₂ , S ₃
This is a drive circuit for operating the output terminal when the switching command signal _S1 from the control circuit 12 is input.
The output of P ₁ is inverted from the power supply voltage level (output voltage level of battery 1) to the ground level, and _the output terminals P _{2 and} It is configured to invert the output of P ₃ from the supply voltage level to the ground level. And the drive circuit 13
The excitation coil 10b of the power switching relay 10 is connected between the output terminal P ₁ of the drive circuit 13 and the second power supply line 4, and the excitation coil 10b of the power supply switching relay 10 is connected between the output terminals P ₂ and P ₃ of the drive circuit 13 and the common energization path 9. Excitation coils 7b and 8b of flashing relays 7 and 8 are connected between them, respectively. Therefore, when the switching command signal S ₁ is output from the control circuit 12, the output terminal P ₁ of the drive circuit 13 is inverted to the ground level, and accordingly, the excitation coil 10b of the power switching relay 10 is The second power supply line 4 is energized regardless of the on/off state of the ignition switch 3, and the power supply switching relay 10 is activated, that is, the normally open side contacts (c and a) of the relay switch 10a are turned on. It is something that will be done. In addition, when the switching command signal S ₁ is not output, the drive command signal is not output from the control circuit 12.
In each case where S ₂ and S ₃ are output, the output terminals P ₂ and P ₃ of the drive circuit 13 are inverted to the ground level, and the blinking relays 7 and 8 are inverted accordingly.
The excitation coils 7b and 8b are energized from the first power supply line 2 through the current detection resistor 11 only when the ignition switch 3 is in the ON state, and the blinking relays 7 and 8 are operated, that is, each The relay switches 7a and 8a are turned on, and the left turn lamp 5 and the right turn lamp 6 are turned on according to the relay switches 7a and 8a.
energized from the common energizing path 9. During such energization, the left turn lamp 5, right turn lamp 6, and excitation coils 7b, 8b are connected to the current detection resistor 11.
The voltage drop across the current detection resistor 11 is output as a voltage signal Sv indicating the load current. Then, this voltage signal Sv is sent to the A-D converter circuit 14.
The signal is inputted to the control circuit 12 via. On the other hand, 15 is a turn signal switch,
It is configured to selectively generate a left turn signal Sa and a right turn signal Sb in accordance with the on-operation state and provide them to the control circuit 12. Further, 16 is a hazard switch, which is configured to generate a hazard signal Sc and provide it to the control circuit 12 in accordance with its on-operation state. Therefore, the control circuit 12 receives the voltage signal from the A-D conversion circuit 14.
The switching command signal S 1 and drive command signals S ₂ , S ₃ are generated based on the left turn signal Sa, right turn signal Sb, hazard signal Sc input from the turn signal switch 15 and hazard switch 16, and a control program stored in _advance. It is configured to output as shown in FIGS. 2 and 3 below.

That is, FIGS. 2 and 3 only show portions of the control program for the control circuit 11 that are related to the gist of the present invention. In FIG. 2, in judgment step a, it is judged whether or not the hazard signal Sc has been input, in other words, whether or not there is a command for hazard operation.If "YES", that is, the hazard switch 16 has been turned on. If it is in the state, the process moves to power switching relay drive step b, and
In the case of "NO", the process moves to power switching relay drive stop step c. In step b of driving the power supply switching relay, the output of the switching command signal _S1 is started, and the force level of the output terminal _P1 of the drive circuit 13 is grounded in response to the output of the switching command signal _S1 . level, the excitation coil 10b of the power supply switching relay 10 is energized from the second power supply line 4, and the relay switch 10a is turned on.
changes from the ON state between contacts (c-b) to contacts (c-a)
It will switch to the on state for a while. After this power supply switching relay drive step b, the hazard execution step d is followed, and then the process proceeds to the next step (not shown). In the hazard execution step d, the drive command signals S ₂ and S ₃ are intermittently output at a predetermined period T, and are therefore output to both the excitation coils 7b and 8b of the flashing relays 7 and 8. From the second power line 4 to the contact point (c-
a) The relay switches 7a and 8a of the flashing relays 7 and 8 are intermittently turned on at a period T. As a result, the left turn lamp 5 and the right turn lamp 6 are intermittently energized from the second power supply line 4 regardless of the on/off state of the ignition switch 3, so that the left turn lamp 5 and the right turn lamp 6 are energized periodically. At T, a hazard operation is performed in which both lights flash.

On the other hand, in the power switching relay drive stop step c, which is entered when the determination step a is "NO" (that is, when the hazard switch 16 is in the off state), the output of the switching command signal _S1 is Therefore, this switching command signal
The output terminal of the drive circuit 13 responds to the stop of the output of _S1 .
The output level of _P1 is reversed to high level, and the excitation coil 10b of the power supply switching relay 10 is cut off, and the relay switch 10a becomes the contact point (c-
b) It will switch to the on state for a while. In the judgment step e, which is carried out subsequent to the power switching relay drive stop step c, it is judged whether or not the left turn signal Sa has been input, in other words, whether or not there is a command to operate the left turn turn signal. If the answer is ``YES'', that is, if the turn signal switch 15 is turned on to the left turn side, the process proceeds to the judgment step g via the left turn turn signal execution step f. In the left turn turn signal execution step f, the drive command signal <sub>S2</sub> is intermittently issued at a predetermined period T, and therefore the first power supply line 2 is output only to the excitation coil 7b of the blinking relay. From ignition switch 3, current detection resistor 1
1 and the contacts (c-b) of the power supply switching relay 10, the relay switch 7a of the blinking relay 7 is intermittently turned on at a period T. As a result, the left turn lamp 5 is intermittently energized from the first power supply line 2 under the condition that the ignition switch 3 is on, and the left turn lamp 5 flashes at a cycle T. A signal action is performed. Said judgment step g
Then, the level of the voltage signal Sv (that is, equivalent to the load current when the left turn turn signal is activated) is set to a predetermined value V <sub>0</sub>
If the answer is ``YES'', the process moves to the next step (not shown), and if the answer is ``NO'', the process moves to the next step (not shown).
In this case, interrupt routine XA, which will be described later, is executed.

If the determination step e is NO, that is, if the turn signal switch 15 is not turned on to the left turn side, the process moves to the left turn turn signal stop step h and a drive command is issued. Stop outputting signal _S2 . Therefore, in this case, the intermittent ON of the relay switch 7a of the flashing relay 7 is stopped, and the left turn turn signal operation is completed. In a judgment step i that is performed subsequent to the left turn turn signal stop step h, it is judged whether or not the right turn signal Sb has been input, in other words, whether there is a command to operate the right turn signal Sb, and it is determined whether or not the right turn signal operation is instructed. '', that is, when the turn signal switch 15 is turned on to the right turn side, the process proceeds to the judgment step g via the right turn turn signal execution step j. In the right turn turn signal execution step j, the drive command signal _S3 is intermittently output at a predetermined period T, and therefore the excitation coil 8 of the blinking relay 8
Electricity is intermittently supplied only to the first power supply line 2 through the contacts (c-b) of the ignition switch 3, the current detection resistor 11, and the power supply switching relay 10 for blinking. A relay switch 8a of the relay 8 is intermittently turned on at a period T.
As a result, the right turn ramp 6 is connected to the first power line 2.
From then on, the ignition switch 3 is intermittently energized on the condition that it is in the on state, and a right turn turn signal operation is executed in which the right turn lamp 5 flashes at a cycle T. Further, if the determination step i is determined to be "NO", that is, if the turn signal switch 15 is not turned on to the right turn side, the process proceeds to right turn turn signal stop step k. After stopping the output of the drive command signal _S3 , the process proceeds to the next step (not shown). Therefore, in this case, the intermittent ON of the relay switch 8a of the blinking relay 8 is stopped, and the right turn turn signal operation is completed.

Now, in the state where "NO" is determined in the judgment step g, that is, the state where the level of the voltage signal Sv from the current detection resistor 11 has become lower than the predetermined value _V0 , the left turn lamp 5 and the right turn lamp 6 This corresponds to a state in which a disconnection occurs in any of the above, and in this case, the interrupt routine XA is executed as described above. That is, FIG. 3 shows the interrupt routine.
XA is shown and will be discussed below.
In the first judgment step 1 of this interrupt routine The program returns to the original program through a cycle change step m, and if "NO" (that is, the right turn lamp 6 is disconnected), the program returns to the original program via a cycle change step n. In the cycle change step m, the output cycle T of the drive command signal _S2 in the left turn turn signal execution step f is changed to, for example, 1/2. The flashing cycle of the lamp 5 is changed to 1/2 of the normal period, and a notification that the left turn lamp 5 is disconnected is made. Furthermore, in the cycle change step n,
The output period T of the drive command signal _S3 in the right turn turn signal execution step j is changed to, for example, 1/2, and therefore, also in this case,
The flashing cycle of the right turn lamp 6 is changed to half of the normal period, and a notification that the right turn lamp 6 is disconnected is made.

According to the present embodiment described above, the common energizing path 9 is controlled by the switching relay 10 only when the turn signal is activated.
Since the current detection resistor 11 is interposed in series with the first power supply line 2 connected to the first power supply line 2, that is, the line through which the load current flows only during the turn signal operation, the current detection resistor 11 is connected to the first power supply line 2 during the hazard operation. As a result, there is no possibility that the amount of heat generated by the current detection resistor 11 increases as in the conventional case.

In the above embodiment, when a disconnection occurs, the flashing cycle T of the left turn lamp 5 or right turn lamp 6 is reduced to 1/
2, but it is of course not limited to this; for example, the left turn lamp 5 or the right turn lamp 6 may be turned on continuously.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with various modifications without departing from the gist thereof.

[Effects of the invention] As is clear from the above explanation, according to the invention, disconnection of the turn signal lamp can be detected based on the voltage drop across the current detection resistor provided so that the load current of the turn signal lamp flows. In the vehicle turn signal and hazard control device configured to detect the present invention, it is possible to achieve a practical effect of suppressing unnecessary heat generation in the current detection resistor during hazard operation.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is an electrical configuration diagram, and FIGS. 2 and 3 are flowcharts showing only part of a control program. In the figure, 1 is the battery, 2 is the first power line,
3 is the ignition switch, 4 is the second power line, 5 is the left turn turn signal lamp (vehicle load), 6 is the right turn turn signal lamp (vehicle load), 7 and 8 are the flashing relays (auxiliary 9 is a common current path, 10 is a power supply switching relay (switch), 11 is a current detection resistor, 12 is a control circuit (detection means), 13 is a drive circuit, 15 is a turn signal switch, 16 is a hazard Shows the switch.

Claims (1)

[Scope of utility model registration request] A turn signal for a vehicle, which selectively flashes one of the turn signal lamps for a left turn and a right turn according to the operating state of a turn signal switch, and also causes both of the turn signal lamps to flash in response to turning on a hazard switch. and a hazard control device, a second power line connected to the battery via an ignition switch;
A second power line is connected directly to the battery, and when the hazard switch is turned off, the first power line is connected to a common path of the left and right turn signal lamps, and the hazard switch is connected to the second power line. a changeover switch that connects the second power supply line to the common energization path when the switch is off, a current detection resistor interposed in series with the first power supply line, and a current detection resistor that detects the A turn signal and hazard control device for a vehicle, comprising a detection means for detecting disconnection of a turn signal lamp.