Wiper apparatus

Abstract

To enable estimation of an operation of a wiper even when an amount of light around a vehicle becomes low.SOLUTION: A wiper apparatus 1 includes a control device 3 that controls a wiper blade WB, and a sensor unit 2 that is disposed within a wiping range R1 of the wiper blade WB on a windshield glass W. The control device 3 includes a wiper operation estimation unit 313 that detects a wiping operation of the wiper blade from a detected light amount of the sensor unit 2, and a usage period determination unit 312 that determines whether estimation of an operation of the wiper blade WB is to be performed by using an actual period of decrease in the detected light amount of the sensor unit 2 or a past period.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wiper device having a function of detecting the operation of a wiper. [Background technology]

[0002] Vehicles are equipped with a wiper device for wiping raindrops off the surface of the windshield glass. Some wiper devices have a function to automatically adjust the operating cycle of the wipers (wiper blades) in response to changes in rainfall conditions (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4281254 Summary of the Invention [Problem to be solved by the invention]

[0004] Automatic adjustment of the duty cycle requires proper detection or estimation of wiper operation. One method is to use an illuminance sensor attached to the windshield glass to detect the decrease in light intensity caused by the wiper passing by and estimate the operation of the wiper. In this method, during the daytime when there is a lot of light around the vehicle, the decrease in light intensity caused by the wipers passing by can be properly detected, and therefore the operation of the wipers can be properly estimated. However, at night when the amount of light is low, it may not be possible to properly detect the decrease in the amount of light caused by the wipers passing by, which may cause problems in estimating the operation of the wipers. Therefore, it is required to be able to appropriately estimate the operation of the wipers even when the amount of light around the vehicle is low. In addition to such requirements, another objective of the present invention is to achieve actions and effects derived from the various configurations disclosed in the "Forms for Implementing the Invention" described below, which actions and effects cannot be obtained with conventional technologies. [Means for solving the problem]

[0005] The present invention provides a control device for controlling the wipers; a sensor disposed within a wiping range of the windshield glass by the wiper; A wiper device having The control device an operation estimation unit that estimates the operation of the wiper from the amount of light detected by the sensor; The wiper device has a determination unit that determines whether to use the actual cycle of the decrease in the amount of light detected by the sensor or a past cycle to estimate the operation of the wiper. [Effects of the Invention]

[0006] According to the present invention, it is possible to estimate the operation of the wipers even when the amount of light around the vehicle is low. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a schematic diagram illustrating a general configuration of a wiper device. [Figure 2] 1 is a schematic diagram illustrating an example of the arrangement of a sensor unit on a windshield glass of a vehicle. [Figure 3] 5A and 5B are diagrams illustrating the relationship between a drive signal input to a wiper drive motor and an output signal from an illuminance sensor unit. [Figure 4] 5A and 5B are diagrams illustrating the relationship between an output signal of an illuminance sensor unit and an output signal of a raindrop sensor unit. [Figure 5] FIG. 10 is a diagram illustrating an operation period table. [Figure 6] 10 is a flowchart illustrating a rainfall determination process. [Figure 7]10 is a flowchart illustrating a data update process of the operation period table. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described by taking as an example a case where it is applied to a wiper device 1 for a vehicle. FIG. 1 is a schematic diagram illustrating the general configuration of a wiper device 1. As shown in FIG. FIG. 2 is a schematic diagram illustrating an example of the arrangement of the sensor unit 2 on the windshield glass W of the vehicle V. As shown in FIG.

[0009] As shown in FIG. 1, the wiper device 1 includes a sensor unit 2 and a control device 3. As shown in FIG. 2, the sensor unit 2 is disposed on the windshield glass W within a wiping range R1 of the wiper blade WB. As an example, the sensor unit 2 is a rain light sensor that combines the functions of an illuminance sensor for detecting illuminance (brightness) and a raindrop sensor for detecting raindrops. Note that the sensor unit 2 may be replaced with an illuminance sensor and a raindrop sensor that are independent of each other.

[0010] As shown in FIG. 1, the sensor unit 2 includes an illuminance sensor section 21 for realizing the function of an illuminance sensor, and a raindrop sensor section 22 for realizing the function of a raindrop sensor. The sensor unit 2 is attached to the inner surface (the surface facing the passenger compartment) of the windshield glass W. In this state, the illuminance sensor unit 21 and the raindrop sensor unit 22 are arranged with their respective detection units in contact with the inner surface of the windshield glass W.

[0011] The illuminance sensor unit 21 is an optical sensor that detects the brightness around the vehicle V, preferably above the vehicle V. As an example, the illuminance sensor unit 21 has a light receiving element (not shown) that receives light that has passed through the windshield glass W. The illuminance sensor unit 21 outputs a voltage value corresponding to the amount of light (detected light amount) received by the light receiving element (not shown). As an example, the voltage value output by the illuminance sensor unit 21 is higher when the illuminance is high (bright) than when the illuminance is low (dark).

[0012] The raindrop sensor unit 22 is a rain sensor that detects the presence or absence of rainfall and the degree of rainfall (amount of rainfall, rainfall volume). As an example, the raindrop sensor unit 22 includes a light-emitting element (not shown) that emits light toward the windshield glass W, and a light-receiving element (not shown) that receives light reflected by the windshield glass W. The raindrop sensor unit 22 outputs a voltage value corresponding to the amount of light (detected light amount) received by a light-receiving element (not shown). As an example, the amount of light received by the light-receiving element decreases as the number of raindrops adhering to the surface of the windshield glass W increases. The amount of raindrops adhering to the surface of the windshield glass W increases as the amount of rainfall increases. Therefore, the voltage value output by the raindrop sensor unit 22 decreases as the amount of rainfall increases.

[0013] The configuration of the light sensor unit and the raindrop sensor unit is exemplified in JP 2018-103725 A, as an example.

[0014] The sensor unit 2 is connected to an input / output port 33 of the control device 3 via an in-vehicle network. The output voltage (output signal) of the sensor unit 2 (illuminance sensor section 21, raindrop sensor section 22) is input to the control device 3 via the input / output port 33. Examples of in-vehicle networks include a CAN network (Controller Area Network) and a LIN network (Local Interconnect Network).

[0015] The control device 3 includes a processing unit 31, a storage unit 32, and an input / output port 33. The processing unit 31, the storage unit 32, and the input / output port 33 are connected to one another via a bus 30. The processing unit 31 is an arithmetic processing device such as an MPU (Micro Processing Unit). The storage unit 32 is an information recording medium such as an SSD (Solid State Drive), an HDD (Hard Disk Drive), or a memory.

[0016] The storage unit 32 stores a program for performing a wiping operation by the wiper blade WB, a program for executing a detection process for the wiper blade WB, and the like. In this embodiment, the processing unit 31 executes various processes based on programs stored in the storage unit 32. The storage unit 32 also stores data generated during the processing by the processing unit 31 and data to be referenced. In this embodiment, the storage unit 32 stores an operation period table 321. In the operation cycle table 321, the operation cycle (Pe) of the wiper blade WB when the wiper blade WB performs a wiping operation and the interval (In) at which the wiper blade WB passes through the area of ​​the sensor unit 2 are stored in association with the operation mode (to be described later) of the wiper device 1. The data stored in this operation cycle table 321 is an example of data referenced during processing, and corresponds to the "past cycle" in the present invention.

[0017] The processing unit 31 has, as functional blocks, a wiper control unit 311, a usage cycle determination unit 312 (determination unit), a wiper operation estimation unit 313, a rainfall amount estimation unit 314, and a data update unit 315.

[0018] The wiper control unit 311 controls the wiping operation of the wiper blade WB. The wiper control unit 311 outputs a drive signal to the wiper drive motor 23 at a timing determined according to the operation mode of the wiper device 1 (wiper blade WB).

[0019] When a drive signal is input, the wiper drive motor 23 is driven to cause the wiper blade WB to wipe the windshield glass W. Here, the wiping operation of the wiper blade WB is a reciprocating movement in which the wiper blade WB is moved from the retracted position shown by the solid line in FIG. 2 to the extended position shown by the imaginary line, and then returned to the retracted position. During this wiping operation, the wiper blade WB crosses the area of ​​the windshield glass W where the sensor unit 2 is provided twice (see FIG. 2).

[0020] As an example, in this embodiment, the wiper device 1 has the following operating modes available: "Continuous operation 1," "Continuous operation 2," "Continuous operation 3," "Intermittent operation 1," "Intermittent operation 2," and "Intermittent operation 3" (see FIG. 5). "Continuous operation" is an operating mode in which, after one wiping stroke, the next wiping stroke is performed without waiting. In "Continuous operation 1," "Continuous operation 2," and "Continuous operation 3," the wiping speed (v1, v2, v3) of the wiper blade WB decreases in this order (v1>v2>v3). "Intermittent operation" is an operation mode in which, after one wiping operation has been performed, the next wiping operation is performed after a predetermined waiting time has elapsed. "Intermittent operation 1", "Intermittent operation 2", and "Intermittent operation 3" have the longest waiting times Wt1, Wt2, and Wt3 in this order (Wt1 <Wt2<Wt3)。 For convenience of explanation, an example has been given in which there are three types of continuous operation and three types of intermittent operation, but the types of continuous operation and intermittent operation can be changed as appropriate.

[0021] The utilization cycle determination unit 312 (determination unit) determines the cycle to be used when estimating the operation of the wiper blade WB. Specifically, the utilization cycle determination unit 312 determines whether to use (a) the actual cycle of the decrease in the amount of light detected by the illuminance sensor unit 21 or (b) a past cycle when the wiper operation estimation unit 313 (described later) estimates the operation of the wiper blade WB.

[0022] The wiper operation estimation unit 313 estimates the operation of the wiper blade WB using the cycle (actual cycle or past cycle) determined by the utilization cycle determination unit 312.

[0023] As described above, during one reciprocating wiping motion of the wiper blade WB, the wiper blade WB crosses the area of ​​the windshield glass W where the sensor unit 2 is provided twice. Therefore, when the wiper blade WB crosses, the amount of light detected by the illuminance sensor unit 21 temporarily decreases twice.

[0024] 3 is a diagram illustrating the relationship between the drive signal Sg input to the wiper drive motor 23 and the output voltage (output signal) of the illuminance sensor unit 21. In Fig. 3, (a) is the drive signal Sg, and (b) and (c) show the waveform of the output voltage of the illuminance sensor unit 21 when the wiper blade WB performs a wiping operation based on the drive signal Sg. Note that Fig. 3(b) shows the waveform of the output voltage when the surroundings of the vehicle are bright, for example, during the day, and Fig. 3(c) shows the waveform of the output voltage when the surroundings of the vehicle are dark, for example, during the night.

[0025] As described above, the wiper control unit 311 outputs the drive signal Sg at a timing determined according to the operation mode of the wiper device 1. The wiper drive motor 23 performs the reciprocating movement of the wiper blade WB at the timing when the drive signal Sg is input.

[0026] 2 from the retracted position indicated by the solid line toward the extended position indicated by the imaginary line (see arrow a in the figure). During this process, the output voltage of the illuminance sensor unit 21 drops when the wiper blade WB crosses the illuminance sensor unit 21 (see peak Pka in the figure). After reaching the extended position, the wiper blade WB moves toward the retracted position (see arrow b in the figure). During this process, the output voltage of the illuminance sensor unit 21 drops when the wiper blade WB crosses the illuminance sensor unit 21 (see peak Pkb in the figure).

[0027] Thus, during one reciprocating wiping operation of the wiper blade WB, there are two timings when the output voltage of the illuminance sensor unit 21 drops. Here, the drop in the output voltage of the illuminance sensor unit 21 occurs because the wiper blade WB blocks the reception of light by a light receiving element (not shown) of the illuminance sensor unit 21. Therefore, when the output voltage of the illuminance sensor unit 21 drops, the wiper blade WB is located at the position of the sensor unit 2 (illuminance sensor unit 21).

[0028] Therefore, the wiper operation estimation unit 313 can estimate that the wiper blade WB is at the position of the illuminance sensor unit 21, that is, the position of the wiper blade WB, based on the drop in the output voltage of the illuminance sensor unit 21. Furthermore, when the output voltage of the illuminance sensor unit 21 drops twice in a short period of time, it can be inferred that the wiper blade is moving back and forth. When the output voltage of the illuminance sensor unit 21 drops twice in a short period of time periodically, it can be inferred that the wiper blade WB is performing a wiping operation.

[0029] When the wiping action of the wiper blade WB is repeated at predetermined intervals, an output waveform such as that shown in (b) of Figure 3 is obtained. Specifically, a pair of peaks Pka and Pkb separated by a predetermined interval (In) appear repeatedly at a predetermined cycle (Pe). Here, the period (Pe) is a period determined according to the operation mode. When the operation mode is the "continuous operation" mode, this period (Pe) is a substantially constant period determined according to the wiping speed of the wiper blade WB. When the operation mode is the "intermittent operation" mode, this period (Pe) is a substantially constant period determined according to the wiping speed of the wiper blade WB and the standby time for intermittent operation. Note that in the intermittent operation mode, the longer the standby time, the larger the period Pe becomes.

[0030] The peaks Pka and Pkb are identified, for example, by detecting the timing at which the output voltage value of the illuminance sensor unit 21 becomes less than the threshold value Th21.

[0031] The wiping speed of the wiper blade WB varies depending on the degree of deterioration of the rubber wiper blade WB, the amount of raindrops on the surface of the windshield glass W, and whether or not the surface of the windshield glass W has been treated. Therefore, when estimating the position of the wiper blade WB from the timing of driving the wiper drive motor 23 (the timing of input of the drive signal Sg), the time difference Δt (see (a) and (b) in Figure 3) from the input of the drive signal Sg to the time when the wiper blade WB crosses the illuminance sensor unit 21 varies depending on the degree of deterioration of the wiper blade WB, etc.

[0032] Therefore, when the position of the wiper blade WB is estimated from the timing of input of the drive signal Sg, there is a possibility that the deviation between the estimated position and the actual position will be large. In this embodiment, the position of the wiper blade WB is estimated by detecting a drop in the output voltage when the wiper blade WB crosses the illuminance sensor unit 21. Therefore, the estimated position of the wiper blade WB is closer to the actual position.

[0033] FIG. 4 is a diagram illustrating the relationship between the output signal (output voltage) of the illuminance sensor unit 21 and the output signal (output voltage) of the raindrop sensor unit 22. As shown in FIG. 4, (b) shows the waveform of the output voltage of the raindrop sensor unit 22 when the wiper blade WB is performing a wiping operation. (a) shows the waveform of the output voltage of the illuminance sensor unit 21 when the wiper blade WB is performing a wiping operation, which is when the surroundings of the vehicle are bright, for example, during the daytime. (c) shows the waveform of the output voltage of the illuminance sensor unit 21 when the wiper blade WB is performing a wiping operation, which is when the surroundings of the vehicle are dark, for example, during the night. FIG. 4 illustrates a case where the operation mode of the wiper device 1 is the "continuous operation mode."

[0034] Returning to the explanation of the processing unit 31, the rainfall amount estimation unit 314 determines whether or not rain is falling based on the voltage value Vr (output signal) output by the raindrop sensor unit 22, and if it is determined that rain is falling, estimates the amount of rainfall based on the output voltage (output signal).

[0035] As described above, the amount of light detected by the raindrop sensor unit 22 decreases as the number of raindrops adhering to the surface of the windshield glass W increases. The voltage value output by the raindrop sensor unit 22 decreases as the amount of rainfall increases.

[0036] As an example, the rainfall amount estimation unit 314 identifies a voltage value that is less than the threshold value Th22 among the output voltage values ​​of the raindrop sensor unit 22 as a peak Pk (raindrop detection signal) caused by raindrops. For example, when it is raining and the wiping action of the wiper blade WB is repeated at predetermined intervals, an output waveform such as that shown in FIG. 4(b) is obtained. The rainfall amount estimation unit 314 integrates the output voltage value of Pk caused by raindrops in the output waveform shown in (b) of Figure 4 for a predetermined time, and determines the rainfall state by comparing the integrated value Vsam with a threshold value Th_rain for determining the rainfall amount. Here, the threshold value Th_rain is prepared for each level of rainfall, such as light rain, rain, and heavy rain. The rainfall amount estimation unit 314 compares the integrated value Vsam with each threshold value Th_rain to determine whether or not rain is falling. If it is determined that rain is falling, the rainfall amount is estimated from the integrated value Vsam.

[0037] As described above, in one reciprocating wiping motion of the wiper blade WB, the wiper blade WB crosses the area of ​​the windshield glass W where the sensor unit 2 is provided twice. Therefore, when the wiper blade WB passes over the raindrop sensor unit 22, the amount of light received by the light-receiving element of the raindrop sensor unit 22 (detected light amount) temporarily decreases. Here, the waveform of the output voltage of the raindrop sensor unit 22 includes a voltage drop caused by raindrops and a voltage drop caused by the passage of the wiper blade WB.

[0038] The rainfall amount estimation unit 314 extracts peaks Pk that are less than the threshold value Th22 from the waveform of the output voltage of the raindrop sensor unit 22, and calculates the integrated value Vsam by excluding the voltage peaks occurring when the wiper blade WB passes by from among the extracted voltage peaks.The rainfall amount estimation unit 314 then determines whether or not rain is falling by comparing the integrated value Vsam with a threshold value Th_rain for determining whether or not rain is falling. As an example, the rainfall amount estimation unit 314 determines the rainfall state ("no rainfall" or "rainfall"), and if it determines that it is "rainfall", it identifies the amount of rainfall as either "light rain", "rain", or "heavy rain".

[0039] Here, the sensor unit 2 includes both an illuminance sensor unit 21 and a raindrop sensor unit 22. Therefore, the drop in output voltage due to the passage of the wiper blade WB occurs at approximately the same time in the illuminance sensor unit 21 and the raindrop sensor unit 22. Therefore, it is possible to identify which part of the waveform of the output voltage of the raindrop sensor unit 22 corresponds to the passage of the wiper by comparing it with the waveform of the output voltage of the illuminance sensor unit 21. Furthermore, a temporary drop in output voltage caused by a phenomenon (splash) in which water splashed up by an oncoming vehicle or the like temporarily acts on the area of ​​the sensor unit 2 can be distinguished from the output voltage caused by raindrops.

[0040] As shown in FIG. 3(b), the drop in the output voltage Vl of the illuminance sensor unit 21 caused by the passage of the wiper blade WB can be detected without any problem in the daytime when the surroundings of the vehicle V are bright. However, at night when it is dark around the vehicle V, when the vehicle V is traveling in a tunnel, or when the vehicle V is traveling under an overpass, the amount of light detected by the illuminance sensor unit 21 decreases. In such a case, the difference between the amount of light detected by the illuminance sensor unit 21 when the wiper blade WB is not passing through the sensor unit 2 and the amount of light detected by the illuminance sensor unit 21 when the wiper blade WB is passing through the sensor unit 2 is small. Therefore, the peaks Pka and Pkb in the waveform of the output voltage of the illuminance sensor unit 21 are smaller than those in the daytime (see (c) of FIG. 3). Therefore, it is difficult to identify which part of the waveform of the output voltage of the raindrop sensor unit 22 corresponds to the drop in output voltage (peaks Pka and Pkb) caused by the passage of the wiper blade WB.

[0041] In this embodiment, when the brightness (detected illuminance) around the vehicle is such that it is difficult to identify the peaks Pka and Pkb of the decrease in output voltage caused by the passage of the wiper blade WB, i.e., when the brightness around the vehicle is low, the following is done. (a) The period (Pe) and interval (In) stored in the memory unit 32 (operation period table 321) are treated as the period (Pe) and interval (In) at which peaks Pka and Pkb appear in the waveform of the output voltage of the illuminance sensor unit 21. (b) It is assumed that the peaks PKa' and Pkb' (see alternative waveform in (c) of Figure 4) caused by the passage of the wiper blade WB are present at the position identified by the period (Pe) and interval (In) stored in the operating period table 321. This allows the rainfall amount estimation unit 314 to exclude the peak at the timing of the wiper blade WB passing from the waveform of the output voltage of the raindrop sensor unit 22, determine whether or not it is raining, and if it is raining, estimate the amount of rainfall. In particular, since the period (Pe) and interval (In) are stored for each operation mode, the appropriate period (Pe) and interval (In) according to the operation mode can be obtained from the operation period table 321 to estimate the operation of the wiper.

[0042] FIG. 5 is a diagram illustrating an operation period table. In the operation cycle table 321 of the memory unit 32, the operation cycle (Pe) of the wiper blade WB and the interval (In) when the wiper blade WB crosses the area of ​​the sensor unit 2 twice are stored in association with the operation mode of the wiper device 1.

[0043] As described above, in the present embodiment, three continuous operations and three intermittent operations are prepared as the operation modes of the wiper device 1. Here, the period (Pe) in the case of continuous operations 1 to 3 corresponds to the time required for the wiper blade to return from the storage position through the deployment position to the storage position (the time required for one round trip). In the present embodiment, in the order of continuous operation 1, continuous operation 2, and continuous operation 3, the time required for one round trip of the wiper blade becomes longer (Z < Y < X). "Continuous operation 1", "continuous operation 2", and "continuous operation 3" are in this order, and the wiping speeds (v1, v2, v3) by the wiper blade WB become slower (v1 > v2 > v3). Therefore, the interval (In) between the peak Pka and the peak Pkb becomes wider in the order of "continuous operation 1", "continuous operation 2", and "continuous operation 3" (a1 < a2 < a3).

[0044] In intermittent operations 1 to 3, since the time for the wiper blade WB to stop at the storage position becomes longer (Wt1 < Wt2 < Wt3), the period (Pe) during which the wiping operation by the wiper blade WB is performed becomes longer in the order of "intermittent operation 1", "intermittent operation 2", and "intermittent operation 3" (X + Wt1 < X + Wt2 < X + Wt3).

[0045] Here, the time required for one round trip of the wiper blade WB varies, for example, depending on the production lot of the wiper blade, the degree of deterioration of the wiper blade, the amount of raindrops adhering to the surface of the windshield glass W, and the presence or absence of surface treatment of the windshield glass W. Therefore, the actual values of the operation period (Pe) and the interval (In) in the wiping operation of the wiper blade WB may be different from the initial values or the registered values, and the differences from the initial values or the registered values also change due to time-dependent factors and environmental factors.

[0046] Therefore, in the control device 3, the data update unit 315 provided in the processing unit 31 is configured to update the values of the period (Pe) and the interval (In) registered in the operation period table 321 as necessary.

[0047] The data update unit 315 determines whether or not the operation cycle table 321 should be updated during rainfall while the wiper blade WB is performing a wiping operation. Specifically, the data update unit 315 allows updating when the brightness (illuminance) around the vehicle V is such that the peaks (Pk1, Pk2) of the drop in output voltage caused by the passage of the wiper blade WB can be identified from the waveform of the output voltage of the illuminance sensor unit 21.

[0048] In this embodiment, when the output voltage Vl of the illuminance sensor unit 21 is greater than the threshold value Th_ref (Vl>Th_ref), the data update unit 315 is permitted to perform update. Here, as an example, the threshold value Th_ref is determined with reference to the average brightness during the daytime, because it is easier to accurately identify the decrease in output voltage of the illuminance sensor unit 21 caused by the passage of the wiper blade WB during the daytime.

[0049] When the data updating section 315 is permitted to update, the data updating section 315 determines whether or not the operation period table 321 needs to be updated. Specifically, the data update unit 315 calculates the actual values ​​of the operation cycle (Pe) and interval (In) in the wiping operation of the wiper blade WB at that time from the waveform of the output voltage of the illuminance sensor unit 21. The data update unit 315 compares the calculated operation cycle (Pe) and interval (In) with the operation cycle (Pe) and interval (In) stored in the operation cycle table 321 to determine whether the operation cycle table 321 needs to be updated. Specifically, the data update unit 315 calculates the difference between the calculated cycle (Pe) and interval (In) and the operation cycle (Pe) and interval (In) stored in the operation cycle table 321, respectively. If the calculated difference is greater than the threshold value Th_Dif, the data update unit 315 updates the data update unit 315 by replacing the operating period (Pe) and interval (In) stored in the operating period table 321 with the calculated period (Pe) and interval (In).

[0050] Here, the data update unit 315 updates the data for each operation mode. For example, when a wiping operation is being performed by the wiper blade WB in the "continuous operation 3" mode during the daytime when it is raining, the period (Pe) and interval (In) are calculated based on the waveform of the output voltage of the illuminance sensor unit 21 while the wiping operation is being performed. Then, if the difference between the calculated period (Pe) and interval (In) associated with "Continuous Operation 3" in the operation period table 321 is greater than the threshold value Th_Dif, the data update unit 315 updates the calculated period (Pe) and interval (In). As a result, the cycle (Pe) and interval (In) associated with "continuous operation 3" in the operation cycle table 321 are updated with the newly calculated cycle (Pe) and interval (In). Therefore, the period (Pe) and interval (In) stored in the operation period table 321 reflect the actual operation of the wiper.

[0051] Here, the case where the calculated operating cycle (Pe) and interval (In) are compared with the operating cycle (Pe) and interval (In) stored in the operating cycle table 321 is exemplified. (a) Only one of the calculated operating cycle (Pe) and interval (In) may be compared. Also, (b) when the calculated operating cycle (Pe) and interval (In) are compared with the operating cycle (Pe) and interval (In) stored in the operating cycle table 321, if the difference between either one is greater than the threshold value Th_Dif, both the operating cycle (Pe) and interval (In) or the one exceeding the threshold value Th_Dif may be updated. Furthermore, the threshold value Th_Dif may be set to an independent value for each of the operation cycle (Pe) and the interval (In).

[0052] The control device 3 may include a communication unit 24 (see FIG. 1) that can communicate with the outside via a network, etc. As an example, the operation period table 321 may be stored in an external device, and the operation period (Pe) and interval (In) may be read from the operation period table 321 by referring to the external device as needed.

[0053] The processing executed by the processing unit 31 of the wiper device 1 will be described below. The processing unit 31 of the wiper device 1 has a function of determining whether it is raining based on the amount of light detected by the raindrop sensor unit 22 and updating the data in the operation cycle table 321 . FIG. 6 is a flowchart illustrating the rainfall determination process executed by the processing unit 31.

[0054] When the system of the vehicle V is started, an output voltage determined according to the amount of light detected by the illuminance sensor unit 21 and an output voltage determined according to the amount of light detected by the raindrop sensor unit 22 are continuously input from the sensor unit 2 to the control device 3. Here, the start of the system of vehicle V means, for example, when the power switch is turned on in the case of a vehicle that runs on the driving force of a motor or a vehicle that runs on the driving force of a motor and an engine, or when the engine is started or when power is supplied to the start motor for starting the vehicle in the case of a vehicle that runs on the driving force of an engine.

[0055] First, the utilization cycle determination unit 312 determines data to be used for rainfall determination (rainfall determination data) (step S101). As an example, the utilization cycle determination unit 312 compares the output voltage Vl of the illuminance sensor unit 21 with a threshold value Th1 (first threshold value) for determining switching, and determines the rainfall determination data.

[0056] Here, the threshold value Th1 for determining switching is a threshold value for determining whether to use (a) the period (Pe) and interval (In) determined from the output voltage Vl of the illuminance sensor unit 21, or (b) the period (Pe) and interval (In) stored in the operation period table 321, when determining rainfall in the rainfall amount estimation unit 314. Here, (a) corresponds to the actual period of decrease in the amount of light detected by the sensor, and (b) corresponds to the past period of decrease in the amount of light detected by the sensor.

[0057] If the output voltage Vl of the illuminance sensor unit 21 is greater than the threshold value Th1 for switching determination (Vl>Th1), the utilization period determination unit 312 determines (a) the period (Pe) identified from the output voltage Vl of the illuminance sensor unit 21 as the data to be used for determining rainfall. On the other hand, if the output voltage Vl of the illuminance sensor unit 21 is equal to or lower than the threshold value Th1 for switching determination (Vl≦Th1), the utilization cycle determination unit 312 (b) determines the periods (Pe) and (In) stored in the operation cycle table 321 as the data to be used for determining rainfall.

[0058] As described above, the output voltage Vl of the illuminance sensor unit 21 decreases when the wiper blade WB crosses the area of ​​the sensor unit 2 (illuminance sensor unit 21). The degree of decrease in the output voltage increases as the brightness of the surroundings of the vehicle V increases, and decreases as the brightness of the surroundings of the vehicle V decreases. That is, the peak Pk (Pka, Pkb) of the decrease in the output voltage Vl becomes larger as the brightness around the vehicle V becomes brighter, and becomes smaller as the brightness around the vehicle V becomes darker.

[0059] For example, when the vehicle V is traveling at night, in a tunnel, or under an overpass, the degree of voltage drop (peaks Pka, Pkb) caused by the passage of the wiper blade WB becomes smaller (see (c) of FIG. 3). As a result, the peak Pk appearing in the waveform of the output voltage Vl becomes smaller, making it difficult to detect the presence of the peak Pk, and as a result, it becomes difficult to identify the passage of the wiper blade WB from the output voltage Vl of the illuminance sensor unit 21.

[0060] Here, in the waveform of the output voltage Vl of the illuminance sensor unit 21 when the surroundings of the vehicle are bright, the peak Pk of the voltage drop caused by the passage of the wiper blade WB has a sufficient magnitude. Therefore, in this embodiment, the occurrence frequency (period (Pe) and interval (In)) of the peak Pk of the voltage drop caused by the passage of the wiper blade WB is calculated from the waveform of the output voltage Vl of the illuminance sensor unit 21 when the surroundings of the vehicle are bright, and is stored in advance in the operation period table 321.

[0061] Therefore, when the output voltage Vl of the illuminance sensor unit 21 is equal to or lower than the threshold value Th1 for switching determination and the surroundings of the vehicle V are dark, the period (Pe) and interval (In) acquired when the surroundings of the vehicle V are bright, i.e., the period (Pe) and interval (In) stored in the operating period table 321, are determined to be the data to be used for determining rainfall.

[0062] Here, the threshold value Th1 is used to determine whether or not a drop (peak Pk) in the output voltage Vl of the illuminance sensor section 21 can be identified when the wiper blade WB crosses the area of ​​the sensor unit 2. For example, threshold value Th1 may be determined based on the output voltage value of the illuminance sensor unit at a brightness intermediate between average daytime brightness and average nighttime brightness. Here, it is preferable to use output voltage Vl of illuminance sensor unit 21 whenever possible for estimating wiper operation. Therefore, waveforms of output voltage Vl may be acquired in advance under different illuminances, and differences in the intensities of voltage drop peaks Pk in the output voltage waveform may be confirmed. The illuminance (voltage value) that realizes the height of the smallest peak Pk that can be confirmed to exist may then be determined as threshold value Th1.

[0063] When the rainfall determination data is determined (step S101), the rainfall amount estimation unit 314 executes a rainfall determination process (step S102). In the rainfall determination process, the integrated value Vsam of the voltage value Vr input from the raindrop sensor unit 22 is compared with each threshold value Th_rain for rainfall determination to determine whether or not it is raining. As an example, when the integrated value Vsam of the voltage value Vr input from the raindrop sensor unit 22 is smaller than each threshold value Th_rain for rainfall determination (Vsam < Th_rain), it is determined that "it is in a rainfall state". When the integrated value Vsam of the voltage value Vr input from the raindrop sensor unit 22 is greater than or equal to each threshold value Th_rain for rainfall determination (Vsam ≧ Th_rain), it is determined that "it is not in a rainfall state".

[0064] Furthermore, in the rainfall determination process, when it is determined that "it is in a rainfall state", the estimated rainfall amount is executed from the integrated value Vsam of the voltage value Vr input from the raindrop sensor unit 22. Since the estimation of the rainfall amount has been described above, the description is omitted here.

[0065] When it is determined that it is in a rainfall state (step S103, Yes), the wiper control unit 311 determines the operation mode of the wiper device 1 based on the estimated rainfall amount (step S104).

[0066] The wiper control unit 311 starts the wiping operation by the wiper blade WB in the determined operation mode (step S105), and then returns to step S101. At this time, the wiper control unit 311 outputs the drive signal Sg to the wiper drive motor 23 at the timing determined according to the determined operation mode (see FIG. 3). Thereby, one reciprocating wiping operation of the wiper blade WB is repeatedly executed at the speed and timing determined according to the operation mode.

[0067] If the result of the rainfall determination process indicates that it is not raining (step S103, No), the wiper operation estimation unit 313 checks whether a wiping operation by the wiper blade WB is currently being performed (step S106). If a wiping operation by the wiper blade WB is currently being performed (step S106, Yes), the wiping operation is terminated (step S107) and the process returns to step S101. If a wiping operation by the wiper blade WB is not currently being performed (step S106, No), the process returns directly to step S101.

[0068] As a result, while it is determined that it is raining, the processes from step S101 to step S105 are repeatedly executed, and the wiping operation by the wiper blade WB is repeatedly executed.

[0069] While the processes from step S101 to step S105 are repeated, the wiping action by the wiper blade WB continues while the operation mode of the wiper device 1 is changed as needed depending on the amount of rain. If it is determined that it is not raining while the wiping operation is continuing (No in step S103), the process proceeds to step S106, and the wiping operation by the wiper blade WB is stopped (step S107).

[0070] FIG. 7 is a flowchart illustrating the update process of the operation period table 231. When wiping by the wiper blade WB is performed, the data update unit 315 performs an update determination process to check whether or not the information stored in the operation cycle table 321 can be updated. As an example, this update determination process is performed in parallel with the rainfall determination process described above.

[0071] When wiping by the wiper blade WB starts (step S201), the data update unit 315 checks whether the output voltage Vl of the illuminance sensor unit 21 is used to determine the rainfall state in the rainfall amount estimation unit 314 (step S202). If the output voltage Vl of the illuminance sensor unit 21 is not being used (No in step S202), the process returns to step S201. In this case, the rainfall estimation unit 314 uses the period (Pe) and interval (In) stored in the operation period table 321 to determine rainfall, and the brightness around the vehicle V is not sufficient to detect the operation of the wiper blade WB from the output voltage Vl of the illuminance sensor unit 21.

[0072] If the output voltage Vl of the illuminance sensor unit 21 is used (step S202, Yes), the data update unit 315 calculates the period (Pe) and interval (In) of the wiping operation of the wiper blade WB from the output voltage Vl of the illuminance sensor unit 21 for a predetermined period (step S203). Next, the data update unit 315 identifies the wiper operation mode (step S204).

[0073] The data update unit 315 refers to the operation period table 321 and acquires the period (Pe) and interval (In) associated with the identified operation mode (step S205). The data update unit 315 compares the acquired period (Pe) and interval (In) with the period (Pe) and interval (In) calculated in step S203, respectively, and determines whether the data update unit 315 needs to be updated (step S206).

[0074] As an example, the data update unit 315 calculates the difference between the calculated period (Pe) and interval (In) and the operation period (Pe) and interval (In) stored in the operation period table 321, respectively. If the calculated difference is greater than the threshold value Th_Dif (Yes at step S207), the data update unit 315 updates the data update unit 315 (step S208). On the other hand, if the calculated difference is smaller than the threshold value Th_Dif (step S207, No), the process of step S208 is skipped.

[0075] Next, the data update unit 315 checks whether the wiping operation of the wiper blade WB is continuing (step S209). If the wiping operation of the wiper blade WB is continuing (Yes in step S209), the process returns to step S202. As a result, while the wiper blade WB is performing the wiping operation using the output voltage Vl of the illuminance sensor unit 21, the processes from step S202 to step S209 are repeated, and the data update unit 315 is updated as necessary.

[0076] On the other hand, if the wiping operation of the wiper blade WB is not continuing (step S209, No), the process returns to step S201. As a result, the determination of whether or not the data update unit 315 is capable of updating and whether or not it is necessary is suspended until a new wiping operation by the wiper blade WB is started.

[0077] The actual values ​​of the wiping cycle (Pe) and interval (In) of the wiper blade WB may differ from the initial or registered values, and the difference from the initial or registered values ​​may change over time or due to environmental factors. Therefore, when there is a large difference between the actual values ​​of the period (Pe) and interval (In) of the wiping action of the wiper blade WB and the period (Pe) and interval (In) values ​​registered in the operation period table 321, the data update unit 315 replaces the period (Pe) and interval (In) values ​​registered in the operation period table 321 with the period (Pe) and interval (In) values ​​obtained in the most recent wiping action of the wiper blade. This allows the cycle (Pe) and interval (In) registered in the operation cycle table 321 to approach the actual values ​​of the cycle (Pe) and interval (In) of the wiping operation of the wiper blade WB. Therefore, when the amount of light received by the sensor unit 2 is low and the period of the wiping operation of the wiper blade WB is estimated using the period stored in the operation period table 321, the accuracy of estimating the period can be improved.

[0078] In the embodiment described above, the case where the utilization cycle determination unit 312 determines the rainfall determination data by comparing the output voltage Vl of the illuminance sensor unit 21 with the threshold value Th1 (first threshold value) for switching determination has been exemplified. The usage cycle determination unit 312 may determine the rainfall determination data based on the distinction between "daytime" and "nighttime." In this case, if it is "daytime," the usage cycle determination unit 312 (a) determines the cycle (Pe) and interval (In) specified from the output voltage Vl of the illuminance sensor unit 21 as the rainfall determination data. If it is "nighttime," the usage cycle determination unit 312 (b) determines the cycle (Pe) and interval (In) stored in the operation cycle table 321 as the rainfall determination data.

[0079] Here, as an example, the distinction between "daytime" and "nighttime" is made based on the current time. The current time can be obtained from a clock (not shown) provided in the processing unit 31, or from an external time server connected via the communication unit 24 (see FIG. 1). The acquired time is then classified as "nighttime" between 7 PM and 7 AM, and "daytime" between 7 PM and 7 PM. The time periods used to distinguish between "nighttime" and "daytime" are changed as appropriate depending on the current date, the latitude and longitude of the vehicle's current location, etc.

[0080] Furthermore, the combination of the current time and the amount of light detected by the sensor unit 2 may be used to distinguish between "daytime" and "nighttime." Furthermore, the period used to estimate the operation of the wiper blade WB can be determined by taking into consideration not only the brightness around the vehicle V, but also the time of day, the amount of decrease in the detected light intensity when the wiper blade WB passes over the sensor unit 2 (S / N ratio of the output voltage), etc.

[0081] Furthermore, when it can be determined from the navigation function of the vehicle or the latitude and longitude of the vehicle's current location that the vehicle is traveling in a mountainous area covered with trees, the period (Pe) and interval (In) stored in (b) the operation period table 321 may be determined as the data for determining rainfall. In this way, in a situation where it is difficult to identify a decrease in the output voltage Vl of the illuminance sensor unit 21, the operation of the wiper blade WB can be appropriately estimated by determining the period (Pe) and interval (In) stored in (b) the operation period table 321 as data for determining rainfall.

[0082] As described above, the wiper device 1 according to the embodiment has the following configuration. (1) The wiper device 1 is A control device 3 that controls the wiping operation of the wiper blade WB (wiper); and a sensor unit 2 (sensor) disposed within a wiping range R1 of the wiper blade WB on the windshield glass W. The control device 3 is a wiper operation estimation unit 313 (operation estimation unit) that estimates the wiping operation of the wiper blade WB from the amount of light detected by the sensor unit 2; The device has a utilization cycle determination unit 312 (determination unit) that determines whether to use the actual cycle of the decrease in the amount of light detected by the sensor unit 2 or a past cycle to estimate the operation of the wiper blade WB.

[0083] With this configuration, when the amount of light around the vehicle V decreases and it becomes difficult to estimate the wiping action of the wiper blade WB from the actual period of decrease in the amount of light detected by the sensor unit 2, the wiping action of the wiper blade WB is estimated from the past period of decrease in the amount of light detected by the sensor unit 2. This allows the operation of the wiper blade WB to be appropriately estimated even when the amount of light around the vehicle V is low.

[0084] (2) In (1) above, The utilization cycle determination unit 312 (determination unit) While the amount of light detected by the sensor unit 2 is equal to or greater than the threshold Th1 (first threshold) for determining switching, the actual cycle of the decrease in the amount of light detected by the sensor unit 2 is determined as the cycle used to estimate the operation of the wiper blade WB. The utilization cycle determination unit 312 (determination unit) While the amount of light detected by the sensor unit 2 is below a threshold Th1 (first threshold) for determining switching, the past cycle of the decrease in the amount of light detected by the sensor unit 2 is determined as the cycle to be used for estimating the operation of the wiper blade WB. The past period of decrease in the detected light amount of the sensor unit 2 is the actual period of decrease in the detected light amount due to the passage of the wiper blade WB when the detected light amount of the sensor unit 2 was greater than or equal to the threshold value Th1 (first threshold value) for switching determination.

[0085] When the amount of light around the vehicle V decreases, it becomes difficult to detect the decrease in the amount of light caused by the passage of the wiper blade WB from the amount of light detected by the sensor unit 2. By setting the threshold value Th1 based on the minimum light intensity at which a decrease in the amount of light due to the passage of the wiper blade WB can be detected, it is possible to quickly determine whether the current amount of light (light intensity) around the vehicle V is bright enough to detect a decrease in the amount of light due to the passage of the wiper blade WB.

[0086] Here, when the amount of light detected by the sensor unit 2 is equal to or greater than the threshold value Th1, that is, when the current amount of light (brightness) around the vehicle V is bright enough to detect a decrease in the amount of light due to the passage of the wiper blade WB, at least the period (Pe) of the decrease in the amount of light is stored. In this way, when the current amount of light (brightness) around the vehicle V is not bright enough to detect a decrease in light amount due to the passage of the wiper blade WB, the operation of the wiper blade can be estimated using the period (Pe) of the decrease in light amount when the brightness was such that a decrease in light amount due to the passage of the wiper blade WB could be detected. This allows the operation of the wiper blades WB to be appropriately estimated even when the amount of light (brightness) around the vehicle V is low.

[0087] (3) In (1) above, The utilization cycle determination unit 312 (determination unit) If it is currently daytime, the actual cycle of the decrease in the amount of light detected by the sensor unit 2 is determined as the cycle to be used for estimating the operation of the wiper blade WB. The utilization cycle determination unit 312 (determination unit) If it is currently nighttime, the past cycle of the decrease in the amount of light detected by the sensor unit 2 is determined as the cycle to be used for estimating the operation of the wiper blade WB. The past period of decrease in the detected light amount by the sensor unit 2 is the actual period of decrease in the detected light amount due to the passage of the wiper blade WB during the daytime.

[0088] With this configuration, the operation of the wiper blade WB can be appropriately estimated by simply distinguishing between "daytime" and "nighttime" and switching between the actual cycle of the decrease in the amount of light detected by the sensor unit 2 and past cycles. As a result, the process of comparing the detected light amount of the sensor unit 2 with the threshold value Th1 is not essential for determining the cycle used to estimate the operation of the wiper blade WB, so that a reduction in the processing load on the processing unit 31 can be expected.

[0089] (4) In (3) above, The usage cycle determination unit 312 (determination unit) distinguishes between nighttime and daytime based on at least one of the time, the amount of light detected by the sensor unit 2, and the decrease in the amount of light detected when the wiper blade WB passes over the sensor unit 2.

[0090] Such a configuration allows for flexibility in distinguishing between "daytime" and "nighttime," and is expected to improve the reliability of estimating the operation of the wiper blade WB.

[0091] (5) In any one of (1) to (4) above, As the operation mode of the wiper device 1 (wiper blade WB), a plurality of operation modes are prepared which differ in the operation cycle (the cycle of one reciprocating wiping operation) of the wiper blade WB. The controller 320 has a table (operation cycle table 321) that stores past cycles of the decrease in the amount of light caused by the passage of the wiper blade WB in association with the operation mode of the wiper device 1. The wiper operation estimation unit 313 obtains from the operation period table 321 the past period of the reduction in light intensity due to the passage of the wiper blade WB, which is linked to the operation mode of the wiper device 1, and estimates the operation of the wiper blade WB from the obtained past period.

[0092] The period of the wiping action of the wiper blade WB differs depending on the operation mode of the wiper device 1. By dividing the period of the decrease in light intensity due to the passage of the wiper blade WB when the amount of light around the vehicle V is equal to or greater than the threshold value Th1 and registering it in the operation period table 321, it is possible to obtain an appropriate period determined according to the operation mode. This allows the operation of the wiper blades to be appropriately estimated, taking into account differences in cycles depending on the operation mode, even when the amount of light (brightness) around the vehicle V is low.

[0093] (6) In (5) above, The operation cycle table 321 includes a data update unit 315 that updates past cycles of the decrease in the amount of light due to the passage of the wiper blade WB stored in the operation cycle table 321. The data update unit 315 If the difference between the actual period of the decrease in light intensity due to the passage of the wiper blade WB and the past period stored in the operation period table 321 is greater than the threshold value Th_Dif (second threshold value), the period stored in the operation period table 321 is replaced and updated with the period of the decrease in light intensity due to the passage of the wiper blade WB while the amount of light around the vehicle V is equal to or greater than the threshold value Th1.

[0094] The wiping speed of the wiper blade WB varies depending on the degree of deterioration of the rubber wiper blade WB, the amount of raindrops on the surface of the windshield glass W, and whether the surface of the windshield glass W has been treated. Therefore, the actual value of the wiping period (Pe) of the wiper blade WB may differ from the initial value or the registered value, and the difference from the initial value or the registered value may change over time or due to environmental factors.

[0095] Therefore, when there is a large difference between the actual value of the period (Pe) of the wiping action of the wiper blade WB and the value of the period (Pe) registered in the operation period table 321, the data update unit 315 replaces the value of the period (Pe) registered in the operation period table 321 with the period obtained in the most recent wiping action of the wiper blade WB. This allows the period (Pe) registered in the operation period table 321 to approach the actual value of the period (Pe) of the wiping operation of the wiper blade WB. Therefore, when the amount of light received by the sensor unit 2 is low and the period stored in the operation period table 321 is used to estimate the operation of the wiper blade WB, the estimation accuracy can be improved.

[0096] (7) In any one of the above (1) to (6), a rainfall amount estimation unit 314 that estimates the amount of rainfall based on the amount of light detected by the sensor unit 2; and a wiper control unit 311 that controls the wiping action of the wiper blade WB based on the estimated amount of rainfall. The rainfall amount estimation unit 314 Based on the operation of the wiper blade WB estimated by the wiper operation estimation unit 313, the amount of rainfall is estimated from the amount of light detected by the sensor unit 2, excluding the influence of the passage of the wiper blade WB.

[0097] As a result, the amount of rainfall is estimated by excluding the amount of light detected at the timing of the wiper blade WB passing from the waveform of the amount of light detected by the sensor unit 2, thereby improving the accuracy of estimating the amount of rainfall.

[0098] (8) In (7) above, The sensor unit 2 is a rain light sensor that combines the functions of an illuminance sensor and a raindrop sensor. The wiper operation estimation unit 313 estimates the operation of the wiper blade WB from the amount of light detected by the illuminance sensor unit 21 (illuminance sensor). The rainfall amount estimation unit 314 estimates the presence or absence of rainfall and the amount of rainfall from the amount of light detected by the raindrop sensor unit 22. In the sensor unit 2, an illuminance sensor section 21 and a raindrop sensor section 22 are arranged adjacent to each other.

[0099] With this configuration, the decrease in the amount of detected light due to the passage of the wiper blade WB occurs at approximately the same time in the illuminance sensor unit 21 and the raindrop sensor unit 22. Therefore, it is possible to identify which part of the detection waveform of the raindrop sensor unit 22 corresponds to the passage of the wiper blade WB by comparing it with the detection waveform of the illuminance sensor unit 21. This makes it possible to estimate the presence or absence of rain and the amount of rainfall while excluding the influence of the passage of the wiper blade WB, thereby improving the accuracy of estimating the amount of rainfall.

[0100] (I) In any one of the above (1) to (8), The illuminance sensor unit 21 and the raindrop sensor unit 22 output a voltage value determined according to the amount of detected light. The voltage values ​​output by the illuminance sensor unit 21 and the raindrop sensor unit 22 increase as the amount of detected light increases. The threshold value Th1 (first threshold value) is set based on a voltage value corresponding to the minimum brightness of the amount of light (brightness) around the vehicle V at which a decrease in the amount of light due to the passage of the wiper blade WB can be detected.

[0101] With this configuration, simply by comparing the output voltage value of the illuminance sensor unit 21 with the threshold value Th1, it is possible to determine whether the brightness (amount of light) around the vehicle V at the current time is bright enough to detect a decrease in the amount of light due to the passage of the wiper blade WB. Therefore, when the current amount of light (brightness) around the vehicle V is not bright enough to detect a decrease in light amount due to the passage of the wiper blade WB, the operation of the wiper blade can be appropriately estimated by switching to the period (Pe) of decrease in light amount when the brightness was such that a decrease in light amount due to the passage of the wiper blade WB could be detected.

[0102] (II) In any one of (1) to (8) and (I) above, The wiper operation estimation unit 313 estimates the operation of the wiper blade WB and the period of the wiping operation of the wiper blade WB from the frequency of occurrence of the timing (peaks Pk1, Pk2) at which the voltage value output by the illuminance sensor unit 21 is less than the threshold value Th21.

[0103] With this configuration, the voltage value output by the illuminance sensor unit 21 can be compared with the threshold value Th21 to identify the peaks (Pk1, Pk2) of the output voltage at the timing when the wiper blade WB passes over the illuminance sensor unit 21. This makes it possible to accurately identify the peaks (Pk1, Pk2) caused by the timing of the passage of the wiper blade WB from the waveform of the output voltage of the raindrop sensor unit 22. This allows the amount of rainfall to be estimated without being affected by the passage of the wiper blade WB, improving the accuracy of estimating the amount of rainfall.

[0104] (III) In any one of (1) to (8), (I), and (II) above, The rainfall amount estimation unit 314 extracts the timing (peak) at which the voltage value output by the raindrop sensor unit 22 becomes less than the threshold value Th22 during a predetermined period while the wiper blade WB is performing a wiping operation, and estimates the presence or absence of rain by comparing the integrated value Vsam of the voltage value at the extracted timing with the threshold value Th_rain for determining rainfall, and if it is or is estimated to be raining, estimates the amount of rainfall.

[0105] With this configuration, the presence or absence of rain and the amount of rain can be estimated without being affected by the passage of the wiper blade WB, improving the accuracy of determining whether rain is falling and estimating the amount of rain.

[0106] (IV) In (5) or (6) above, The operation cycle table 321 is stored in the storage unit 32 included in the control device 3 or in a storage means included in an external device.

[0107] This configuration also makes it possible to appropriately estimate the operation of the wiper blades.

[0108] (V) In any one of (5), (6), or (IV) above, The operating period table 321 stores, for each operating mode of the wiper device 1 (wiper blade WB), the period (Pe) of the decrease in the output voltage Vl of the illuminance sensor unit 21 due to the passage of the wiper blade WB and the interval (In) between the peaks (Pk1, Pk2) of the timing of the decrease in the output voltage. The period of occurrence of the timing (peaks Pk1, Pk2) at which the voltage value (output voltage Vl) output by the illuminance sensor unit 21 becomes less than Th21 is the period of decrease in the output voltage (Pe), and the interval between peaks Pk1 and Pk2 included in the same wiping operation period is the interval (In) between peaks (Pk1, Pk2).

[0109] With this configuration, the operation of the wiper blade WB can be appropriately estimated taking into account the differences in cycles and intervals depending on the operation mode.

[0110] Although the embodiments and modifications of the present invention have been described above, the present invention is not limited to these and can be modified as appropriate within the scope of the technical concept of the invention. [Explanation of symbols]

[0111] 1. Wiper device 2 Sensor Unit 21 Illuminance sensor section 22 Raindrop sensor 23 Wiper drive motor 3. Control device 30 Bus 31 Processing section 311 Wiper control unit 312 Usage cycle determining unit (determining unit) 313 Wiper operation estimation unit (operation estimation unit) 314 Rainfall Estimation Section 315 Data Update Section 32 Storage section 321 Operation Period Table 33 input / output ports R1 Wiping area Th1 threshold (threshold for switching decision) Th21 threshold (threshold for illuminance sensor) Th22 threshold (threshold for raindrop sensor) Th_rain threshold (threshold for determining rainfall) Th_ref threshold (threshold for brightness determination) Th_Dif threshold (threshold for determining table update) V vehicle Vl Output voltage (illuminance sensor part 21) Vr Output voltage (raindrop sensor part 22) W windshield glass WB wiper blade

Claims

1. a control device for controlling the wipers; a sensor disposed within a wiping range of the windshield glass by the wiper; A wiper device having The control device an operation estimation unit that estimates the operation of the wiper; A wiper device comprising: a determination unit that determines whether to use an actual cycle of a decrease in the amount of light detected by the sensor or a past cycle to estimate the operation of the wiper.

2. In claim 1, The determination unit determining the actual cycle as a cycle to be used for estimating the operation of the wiper while the amount of light detected by the sensor is equal to or greater than a first threshold, and determining the past cycle as a cycle to be used for estimating the operation of the wiper while the amount of light detected by the sensor is less than the first threshold; The past period is an actual period of the decrease in the amount of light caused by the passage of the wiper when the amount of light detected by the sensor was equal to or greater than the first threshold.

3. In claim 1, The determination unit If it is currently daytime, the actual period is determined as the period to be used for estimating the operation of the wiper, and if it is currently nighttime, the past period is determined as the period to be used for estimating the operation of the wiper; The past period is an actual period of the decrease in the amount of light caused by the passage of the wiper during the daytime.

4. In claim 3, The determination unit distinguishes between nighttime and daytime based on at least one of time, the amount of light detected by the sensor, and a decrease in the amount of light detected when the wiper passes by the sensor.

5. In any one of claims 2 to 4, The wiper operation modes include a plurality of operation modes with different wiper operation cycles, a table that stores past periods of the decrease in the amount of light due to the passage of the wiper in association with the operation mode of the wiper; The operation estimation unit obtains from the table a past cycle of a decrease in light amount due to the passage of the wiper, which cycle is linked to the operation mode of the wiper, and estimates the operation of the wiper from the obtained cycle.

6. In claim 5, a data updating unit that updates the past cycles of the decrease in the amount of light due to the passage of the wiper stored in the table; The data update unit When a difference between an actual period of the reduction in the amount of light due to the passage of the wiper and a past period stored in the table is greater than a second threshold value, the period stored in the table is updated.

7. In claim 5, a rainfall amount estimation unit that estimates the amount of rainfall based on the amount of light detected by the sensor; a wiper control unit that controls the operation of the wiper based on the estimated rainfall amount, The rainfall estimation unit The wiper device estimates the amount of rainfall based on the wiper operation estimated by the operation estimation unit, while excluding an effect of the wiper passing from the amount of light detected by the sensor.

8. In claim 7, The sensor is a rain light sensor that integrates a function of an illuminance sensor and a function of a raindrop sensor, the operation estimation unit estimates the operation of the wiper from the amount of light detected by the illuminance sensor unit; The rainfall amount estimation unit estimates the amount of rainfall from the amount of light detected by the raindrop sensor unit.

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