JPS6238429Y2 - - Google Patents

Description

[Detailed explanation of the idea]

This invention uses a retriggerable timer for the timer that outputs a wiper drive signal for a certain period of time when the wiper operation switch is operated, and the wiper operation time can be increased by operating the wiper operation switch again while the timer is outputting. This invention relates to a vehicle wiper device that can be extended beyond a set time. The inventors of the present invention proposed that this type of wiper device for wiping the fender mirror be equipped with a timer circuit that outputs an output for a certain period of time from when the wiper operating switch is operated, and that the wiper blade is moved to a predetermined wiping limit position by the output of this timer circuit. We are proposing a device that drives the motor in reverse every time the wiper blade reaches the specified stop position, and when the output from the timer circuit disappears, the output is held and the motor continues to drive until the wiper blade returns to its predetermined stop position. (For example, Japanese Patent Application No. 55-141967 (Japanese Unexamined Patent Publication No. 57-66054). According to such a wiper device, once the wiper operation switch is operated, the wiping operation of the wiper is automatically performed for a certain period of time. , there is no need to keep pressing the switch to drive the wiper, and it is easy to operate.By the way, the output time of the above-mentioned timer circuit is set so that the water droplets can be sufficiently wiped away. For example, if the rain becomes heavier and water drops continue to adhere after operating the wiper operating switch, after the timer circuit has lost output and the wiper blades have stopped operating, operate the wiper operating switch again to restart the wiper blades. However, in order to operate the switch again after waiting for the wiper to stop operating, one has to constantly pay attention to the movement of the wiper blade, which poses the problem of cumbersome operation. This invention was developed with a focus on these problems, and in order to improve wiper operability, it is possible to retrigger a timer circuit that outputs a wiper operation signal for a certain period of time when the wiper operation switch is operated. If the wiper operation switch is operated again while the timer circuit is outputting,
It is an object of the present invention to solve the above-mentioned problems by re-triggering the above-mentioned timer circuit to continue outputting for a certain period of time after the switch is operated again. Hereinafter, the present invention will be explained based on the drawings. 1 and 2 are circuit diagrams showing an embodiment of the present invention, and terminals a, b, c, and d shown in FIG. 1 are respectively terminals a, b, c, and d of the motor drive control circuit shown in FIG. It is designed to be connected to each of b, c, and d. First, to explain the configuration of Fig. 1, 1 is an operating switch, 2 is a timer circuit using a retrigger timer IC3, and the set time is determined by an external resistor.
It is arbitrarily determined by the time constant of R ₀ and capacitor C ₀ . The operating switch 1 is connected between the base of the transistor T ₂₀ and ground, and when the operating switch 1 is off, the transistor T ₂₀ is turned on and prohibits the retrigger timer IC ₃ from operating. When turned on, transistor T ₂₀ is turned off and retrigger timer IC ₃ is activated.
The retrigger timer IC ₃ produces an H level output for a set time determined by the resistor R ₀ and the capacitor C ₀ . The output of timer circuit 2 is a retrigger timer IC ₃ .
An inverter 4 is provided to invert the output of the inverter 4, and the output of the inverter 4 is connected to a self-holding circuit 1 having an invert OR gate 11 and a NAND gate 12.
0 is set. Further, as a position detection means for detecting when the wiper blade reaches the wiping limit position, a rotary contact 7 that reciprocates within a predetermined wiping angle range is used.
and contacts 8 and 9 provided at the limit position of the wiping range.
A wiper blade position detector 5 having a position sensor 5 is provided. The output of the inverter 4 is given as a set input SET to one side of the invert OR gate 11 of the self-holding circuit 10, and the NAND gate 12 to which the output X of the invert OR 11 is input to one side
The contact 8 of the position detector 5 is connected to the other input of the position detector 5, and the L level output when the rotary contact 7 contacts the contact 8 causes a reset to the self-holding circuit.
RESET is applied, and the output of the NAND gate 12 is feedback-connected to the other input Xa of the invert-OR gate 11. Here, the invert OR gate 11 in the self-holding circuit 10
The respective truth tables of the NAND gate 12 and NAND gate 12 are as shown in Tables 1 and 2 below.

【table】

[Table] Next, the configuration of the motor drive control circuit shown in FIG. 2 will be explained. The transistor T ₁ is a transistor that turns on when the output of the self-holding circuit 10 shown in FIG. ₁ is at L level. While the wiper blade is on, the wiper blade drive motor 6 is driven in the reverse direction every time the wiper blade reaches a predetermined wiping limit position. Transistors T ₂ and T ₃ are connected to terminal b,
This is a transistor that is turned on and off by a signal from the position detector 5 with respect to c. When the transistor _T2 is on, the motor 6 is rotated in the forward direction, and when the transistor _T3 is switched on, the motor 6 is rotated in the reverse direction. A switching circuit having transistors T ₄ to _{T 11} is provided as a circuit for rotating the motor 6 in the forward and reverse directions based on the on/off operations of the transistors T _{2 and T 3 .} Next, referring to the time chart in Figure 3,
The operation of the embodiment of the present invention shown in FIG. 2 will be explained. First, in the non-operating state where the operating switch 1 is turned off, the output of the timer circuit 2 is at the L level, so the output of the inverter 4 is at the H level, and the rotating contact in the position detector 5 is at the contact 9. NAND gate 12 of the self-holding circuit 10 from the position detector 5 to be in a predetermined stop position of contact.
The output to is at H level, therefore the input of invert or gate 11 becomes (H, H) and produces an L level output, and the input of NAND gate 12 becomes (L, H) and becomes H level. output (see Tables 1 and 2 above). The H level output from the self-holding circuit 10 is applied between terminals a and b of _the motor drive control circuit shown in FIG. 2, turning off the transistor T1, and turning off the transistor _T1 turns off the transistor T ₂ is also off. On the other hand, the rotating contactor 7 and the contact point 9 in the position detector 5
Transistor T ₃ in the motor drive control circuit of FIG. 2 connected via terminal d by contact with
The base of T3 is also pulled to L level, and transistor _T3 is also turned off. Next, when the operating switch is turned on at time _t1 shown in FIG. 3, the retrigger timer IC ₃ of the timer circuit 2 is activated by turning off the transistor _T20 , and the retrigger timer IC ₃ goes to the H level. It begins to produce output. Such a timer circuit 2
The H-level output from the inverter 4 is inverted to L-level, and the self-holding circuit 10 is set. That is, due to the L level output of the inverter 4, the input of the invert OR gate 11 becomes (H, L).
As a result, an H level output is generated as shown in Table 1 above. Therefore, the input of the NAND gate 12 is (H,
H) and produces an L level output as shown in Table 2 above. At this time, the input of the invert OR gate 11 changes to (L, L), but the output remains at the H level. When the timer circuit 2 generates an H level output, the L level output of the self-holding circuit 10 is applied between terminals a and b of the circuit shown in FIG _{. 2} is turned on. When transistor T ₂ is turned on, transistor T ₄ is also turned on, and then transistors T ₆ and T ₅ are also turned on, and +Vc → T ₆ → Motor 6 →
T ₅ -> A circuit that becomes ground is formed, current flows to the motor 6, and the motor 6 starts rotating in the forward direction. When the motor 6 starts rotating, the rotating contact 7 of the position detector 5 separates from the contact 9, and the transistor T ₃
The ground to the base of T3 is removed and transistor _T3 is turned on. However, transistors T ₇ , T ₈ , T ₉
and T ₁₀ are each in the off state. When the rotary contact 7 of the position detector 5 further rotates due to the rotation of the motor 6 and comes to a position where it contacts the contact 8, a reset signal is sent to the self-holding circuit 10.
RESET changes from H level to L level, the output of NAND gate 12 changes from L level to H level, and transistor _T1 shown in FIG.
By turning off the transistor T2 and grounding the base of the transistor _T2 via the terminal c, the transistor _T2 is also turned off, and the transistors _T4 , _T5 , _T6 and _T11 , which were previously on, are turned off. Become. At this time, the transistor _T3 is already on, so when the transistors _T4 to _T6 and _T11 are turned off, the transistor _T8 is turned on, turning on the transistors _T9 and _T10 , and when the transistor T9 is turned on, the transistor _T8 is turned on. resistance
The base bias of R ₅ and R ₆ turns on transistor T ₇ , thus forming a circuit where +Vc → T ₁₀ → motor 6 → T ₉ → ground, and a current flows in motor 6 in the opposite direction. Then, the motor 6 starts rotating in reverse. This reverse rotation also brings the position detector 5 into rotational contact again.
When the rotating contact 7 comes into contact with the contact 9,
The output of the self-holding circuit 10 changes to the L level and switches to forward rotation in the same manner as described above, and thereafter, while the timer circuit 2 is producing the H level output, the motor 6
The control of forward and reverse rotation is repeated. still,
Timer circuit 2 turns on operating switch 1 at time _t1 .
From when the switch is turned off at time t ₁ ', an H level output is generated for a set time τ. Next, as shown in the time chart in Figure 3,
Time t 2 before the set time τ of timer circuit ₂ elapses
Assuming that the operating switch 1 is operated again, the switching on of the operating switch 1 turns off the transistor T ₂₀ , which restarts the retrigger timer IC ₃ of the timer circuit 2, turning off the operating switch and turning off the transistor T ₂₀ again. The retrigger timer IC ₃ starts to output an H level output for a certain period of time τ from the time t ₂ ' when it is turned on. As a result, even if the set time τ of the timer circuit 2 has elapsed from the time t ₁ ' when the operating switch 1 was operated for the first time, the timer circuit continues to output the H level, and the wiper operation does not stop. The set time τ of timer circuit 2 from time t ₂ '
If the operating switch 1 is turned on again at time _{t 3} before _the elapse of The timer circuit 2 begins to generate an H level output for the time τ, and the timer output stops after the set time τ has elapsed from time t ₃ '. As described above, if the output of the timer circuit 2 returns to the L level after the set time τ has elapsed from time t ₃ ', the output of the inverter 4 becomes the H level, and at this time, as shown in the figure, the position detector 5 If the timing is when the rotating contact 7 comes to a predetermined stop position where it is in contact with the contact 9, the output of the invert OR gate becomes L level when the output of the inverter 4 rises from L level to H level, and the output of the NAND gate becomes L level. Since the output remains at the H level, each of the transistors T ₁ and T ₂ in FIG. The transistor _T3 , which was in use, is turned off, and the motor 6 does not switch to forward rotation, but instead stops the wiper blade at a predetermined stop position. On the other hand, even if the output of the timer circuit 2 stops and goes to the L level when the rotary contact 7 of the position detector is in another position where it does not contact the contact 9, the motor 6 rotates in the forward direction due to the transistor _T2 being turned on. Alternatively, the reverse rotation of the motor ₆ based on the turning on of the transistor T3 continues, and when the rotating contact 7 of the position detector 5 comes into contact with the contact 9 and the transistor _T3 turns off, the motor 6 is driven. will stop. In this way, according to the above embodiment, after operating the activation switch for the first time, if it is predicted that the water droplets will not be removed sufficiently by the wiper operation within the set time, the wiper operation will be activated at that time. By turning on the switch, it becomes possible to further extend the wiper operating time beyond the set time, and the wiper operating time can be extended as desired depending on the degree of wiping off water droplets. FIG. 4 is a circuit diagram showing another embodiment of the present invention, and the circuit shown in FIG. 2 can be used as is for the motor drive control circuit. This embodiment is characterized in that the drive of the wiper, which is operated for a time set by a timer, can be stopped midway by operating a reset switch. That is, the basic configurations of the timer circuit 2, which is retriggered by the operation of the operating switch 1, the position detector 5 that detects and outputs the wiping limit position of the wiper blade, and the self-holding circuit 10 are the same, but the self-holding circuit The NAND gate 12 provided in 10 is a 3-input NAND gate, and this NAND gate 1
A reset switch 30 is provided as one of the inputs of 2,
A reset is forcibly applied by inputting an L level by turning on the reset switch 30. Reset switch 3 like this
The truth table of the NAND gate 12 with an operation input of 0 is as shown in Table 3 below.

[Table] That is, under the H level input when the reset switch 30 is in the OFF state, the self-holding circuit 10 operates in the same manner as shown in FIG.
When the reset switch 30 is turned on, the self-holding circuit 10 is reset, and in this reset state, even if the timer circuit 2 is generating an H level output, the rotating contact 7 of the position detector 5 is not connected to the contact point. 9, the drive of the motor is stopped. Next, the operation of the embodiment shown in FIG. 4 will be explained with reference to the time chart shown in FIG. Each of FIGS. 5a and 5b shows the operation when the reset switch 30 is in the OFF state. In FIG. After τ, the output of the timer circuit 2 returns to the L level and the wiper operation is stopped, and in FIG. By re-operating, the set time τ from the last time actuating switch 1 was operated
Later, the output of the timer circuit 2 returns to the L level and the wiper operation is stopped. FIG. 5c shows a state in which the reset switch 30 is operated after operating the operating switch 1 twice, and as a result of operating the reset switch 30, the input to the NAND gate 12 of the self-holding circuit 10 becomes L level, thereby causing the timer circuit The same state is created when the output of 2 stops and goes to L level,
When the rotating contact 7 of the position detector 5 comes into contact with the contact 9 due to the rotation of the motor 6, the motor 6
drive will be stopped. In Fig. 5d, the wiper is operated by continuing to press and turn on the operating switch 1, and then the operating switch 1 is turned off to start the timer circuit 2 and set the timer circuit 2. time τ
The figure shows the operation in a state where the reset switch 30 is turned on to stop the wiper operation while the wiper is being output. In this case as well, when the reset switch 30 is turned on, the self-holding circuit 10 is reset, and when the rotary contact 7 of the position detector 5 reaches the stop position where it contacts the contact 9, the drive of the motor 6 is stopped. Become so. As explained above, according to the present invention,
A retriggerable timer circuit is provided as a timer circuit that outputs an output for a certain period of time from the time the wiper operation switch is operated to control the drive motor of the wiper blade, and the wiper operation switch is activated again while this timer circuit is outputting. When the switch is operated, the timer circuit is re-triggered so that the output is output for a certain period of time from when the switch is operated to continue the wiper operation. Therefore, if the rain becomes strong while the wiper is operating due to the timer output, water droplets may not adhere to the water droplets. If it is predicted that the wiper will not be wiped, the wiper operation time can be extended by operating the wiper operation switch again if necessary, until a certain period of time has elapsed since the switch operation. Since there is no need to wait for the wiper to stop before operating the wiper operation switch, it is easier to operate the wiper, and the wiper operation time can be extended as necessary depending on the degree of adhesion of water droplets. is obtained. Also, if the reset switch is operated while the wiper is being operated by the timer output,
Since wiper operation can be forcibly stopped regardless of the timer output,
The effect of preventing the wiper from operating is also obtained.

[Brief explanation of the drawing]

Figures 1 and 2 are circuit diagrams showing one embodiment of the present invention, Figure 3 is a time chart showing the operation of the embodiment of Figures 1 and 2, and Figure 4 is a circuit diagram of the present invention equipped with a reset switch. A fifth circuit diagram showing another embodiment of
This figure is a time chart showing the operation of the embodiment of FIG. 4. 1... Operating switch, 2... Timer circuit, 3...
...Retrigger timer IC, 4...Inverter, 5...
...Position detector, 6...Motor, 7...Rotating contact, 8, 9...Contact, 10...Self-holding circuit, 1
1...Invert or gate, 12...Nand gate, 30...Reset switch.

Claims (1)

[Scope of utility model registration request] A motor that drives the wiper blade, a drive control circuit that drives the motor in reverse every time the wiper blade is driven and reaches a predetermined wiping limit position, and an output that is output for a certain period of time from when the wiper operating switch is operated. a retriggerable timer circuit, which operates the drive control circuit by operating the wiper operation switch, and when the wiper operation switch is operated again during the operation, outputs an output for a certain period of time from the time of this operation to continue the operation of the drive control circuit; A wiper device for a vehicle, comprising: an output holding circuit that continues outputting to the drive control circuit until the wiper blade returns to a predetermined stop position when the output of the timer circuit disappears.