JP5180542B2 - Wiper device - Google Patents

Description

  The present invention relates to a wiper device, and more particularly to a wiper device that wipes raindrops and the like by reciprocating a wiper.

  2. Description of the Related Art Conventionally, a vehicle such as an automobile is provided with a wiper device for wiping raindrops attached to a windshield due to rain or the like.

By the way, in the wiper device, since the wiper is reciprocated through a transmission device such as a crank, a high load may be generated immediately before the wiper reaches the reverse position. Therefore, Patent Document 1 discloses a technique for controlling a torque delivered from a driving device such as a motor according to a crank position by a control device.
JP 2005-502545 A

  By the way, in the wiper device, the coefficient of friction between the wiper and the windshield changes greatly when the windshield is wet and dry, and the force required to reciprocate the wiper also changes greatly. Even if the wiper is reciprocated within a predetermined operating range, the wiper blade may be deformed due to a change in the friction coefficient, and the wiper reversal position may be inside the original position, resulting in a narrow operating range. is there.

  However, the technique disclosed in Patent Document 1 has a problem that the frictional state of the wiping surface wiped by the reciprocating motion of the wiper is not particularly taken into consideration.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a wiper device that can suppress the operation of the wiper in consideration of the friction state of the wiping surface.

In order to achieve the above object, the invention described in claim 1 is a motor that reciprocates a wiper, a detection unit that detects a position of the wiper within an operation range in which the wiper reciprocates, and an operation of the wiper. For each position within the range, when the wiper is reciprocated, storage means that stores in advance predicted voltage information indicating a predicted voltage that is predicted to be supplied to the motor, and when the wiper is reciprocated, A control means for controlling the voltage supplied to the motor; and a difference between the voltage supplied to the motor by the control of the control means and the predicted voltage indicated by the predicted voltage information corresponding to the position detected by the detecting means. based on, and an estimation means for estimating a friction state with respect to the wiper wiping surface is wiped by the reciprocating movement of the wiper, wherein the storage unit, the operation of the wiper For each position in the enclosure, a plurality of the predicted voltage information and the threshold value of the difference in which the friction state of the wiping surface is different are stored in advance, and the estimation means is indicated by the voltage supplied to the motor and each predicted voltage information The frictional state of the wiping surface with respect to the wiper is estimated based on the result of comparing the difference between the predicted voltage and the predicted voltage with the threshold value .

  According to the first aspect of the present invention, the wiper is reciprocated by the motor, and the position of the wiper within the operation range in which the wiper reciprocates is detected by the detecting means.

  Further, predicted voltage information indicating a predicted voltage predicted to be supplied to the motor when the wiper is reciprocated at each position within the operation range of the wiper is stored in advance by the storage unit, and is controlled. The means controls the voltage supplied to the motor when the wiper reciprocates.

  In the present invention, the wiper reciprocates based on the difference between the voltage supplied to the motor by the control of the control unit and the predicted voltage indicated by the predicted voltage information corresponding to the position detected by the detection unit. The frictional state of the wiping surface wiped by the operation with respect to the wiper is estimated.

Therefore, according to the first aspect of the present invention, based on the difference between the voltage that is actually supplied to the motor and the predicted voltage that is predicted to be supplied to the motor stored in advance for each position within the operating range of the wiper. Thus, the friction state of the wiping surface wiped by the reciprocating motion of the wiper with respect to the wiper can be estimated. Therefore, the operation of the wiper can be suppressed in consideration of the friction state of the wiping surface. Further, the storage means stores in advance a plurality of predicted voltage information and a threshold value of the difference in which the friction state of the wiping surface differs for each position within the operation range of the wiper, and the estimation means includes the motor The friction state of the wiping surface with respect to the wiper is estimated based on the result of comparing the difference between the voltage supplied to the predicted voltage and the predicted voltage indicated by each predicted voltage information with the threshold value. Therefore, it can be easily estimated which friction state the wiping surface is in a plurality of different friction states.

  According to the present invention, as in the invention described in claim 2, the predicted voltage information indicates the predicted voltage when the wiper reciprocates when the friction state of the wiping surface is a predetermined state. The estimating means estimates that the friction state of the wiping surface is different from the predetermined state when the difference is equal to or greater than a predetermined amount.

  Therefore, according to the second aspect of the invention, it can be easily estimated whether or not the friction state of the wiping surface is a predetermined state.

According to a third aspect of the present invention, when the control unit reciprocates the wiper, the predicted voltage information for each position within the operation range stored in the storage unit is provided. Are corrected in accordance with the difference between the predicted position and the position detected by the detecting means, and the corrected predicted voltage is corrected. Is supplied to the motor.

According to an eighth aspect of the present invention, there is provided a motor for reciprocating the wiper, a detecting means for detecting the position of the wiper within the operating range in which the wiper reciprocates, and each position within the operating range of the wiper. Each time the wiper is reciprocated, a storage means that stores in advance predicted voltage information indicating a predicted voltage that is expected to be supplied to the motor, and a storage means that stores the wiper when the wiper is reciprocated. The predicted voltage information for each position within the operated range is read in the order of the predicted position of the wiper, and the predicted voltage indicated by the read predicted voltage information is detected by the predicted position and the detection means. corrected according to the difference between the position, is supplied to the motor control means corrected predicted voltage is controlled to be supplied to the motor, the control of the control means Estimating means for estimating the friction state of the wiping surface to be wiped by the reciprocating motion of the wiper based on the difference between the pressure and the predicted voltage indicated by the predicted voltage information corresponding to the position detected by the detecting means And the storage means stores in advance a plurality of predicted voltage information and a threshold value of the difference in which the friction state of the wiping surface is different for each position within the operation range of the wiper, and the estimation means The friction state of the wiping surface with respect to the wiper is estimated based on the result of comparing the difference between the voltage supplied to the motor and the predicted voltage indicated by each predicted voltage information with the threshold value .

Therefore, according to the third and eighth aspects of the invention, the wiper with respect to the change in the friction state is obtained by estimating the friction state and switching the operation state of the motor regardless of the position of the wiper in the operation range. Responsiveness is improved.

According to a third aspect of the present invention, as in the fourth aspect of the present invention, the apparatus further comprises supply means for supplying a voltage corresponding to the duty ratio of the input pulse width modulation signal to the motor, and the predicted voltage information. Indicates the predicted voltage by the duty ratio of the pulse width modulation signal, and the control means performs the reciprocating operation of the wiper, and the predicted voltage for each position within the operation range stored in the storage means. The information is read in the order of the predicted position of the wiper, the duty ratio indicated by the read predicted voltage information is corrected according to the difference between the predicted position and the position detected by the detection means, and the corrected duty The voltage supplied to the motor is controlled by outputting the ratio pulse width modulation signal to the supply means.

Therefore, according to the invention of claim 4 , even when the voltage supplied to the motor is controlled by the duty ratio of the pulse width modulation signal, the friction state can be estimated from the duty ratio. The responsiveness of the wiper to the change of the friction state is improved.

  Further, the responsiveness is improved as compared with the method in which the duty ratio is determined only by the difference between the command angle and the detected angle from the angle sensor.

According to a fourth aspect of the present invention, as in the fifth aspect of the present invention, the control unit multiplies the difference by a predetermined coefficient with respect to the duty ratio indicated by the read predicted voltage information. The correction is performed by adding a value obtained by multiplying the integrated value obtained by integrating the difference and a predetermined coefficient.

Therefore, according to the fifth aspect of the present invention, the wiper can be controlled to the target operating state even when a disturbance occurs and the friction state of the wiping surface changes.

Further, in the invention according to claim 4 or claim 5, as in the invention according to claim 6 , the control unit detects the power supply voltage and indicates the predicted voltage information according to the detected change in the power supply voltage. Correct the duty ratio.

Therefore, according to the sixth aspect of the present invention, the wiper can be controlled to the target operating state even when the power supply voltage changes.

According to a fourth to sixth aspect of the invention, as in the seventh aspect of the invention, the estimating means is stored in the storage means and the duty ratio of the pulse width modulation signal output by the control means. Further, the friction state is estimated based on the difference from the duty ratio indicated by the predicted voltage information corresponding to the position detected by the detecting means.

Therefore, according to the seventh aspect of the invention, the friction state of the wiping surface can be estimated from the duty ratio of the pulse width modulation signal.

Further, according to the present invention, as in the ninth aspect of the invention, the control means increases the voltage supplied to the motor as the magnitude of friction with respect to the wiper of the wiping surface estimated by the estimation means increases. Control to raise.

Therefore, according to the ninth aspect of the present invention, it is possible to suppress the change in the operation speed of the wiper according to the change in the friction state of the wiping surface.

According to a tenth aspect of the present invention, as in the tenth aspect of the present invention, the motor causes the wiper to reciprocate by reciprocatingly rotating a rotating shaft, and the control means is the wiping surface estimated by the estimating means. As the magnitude of friction with respect to the wiper increases, the angle range over which the rotary shaft reciprocates is controlled.

Therefore, according to the tenth aspect of the present invention, it is possible to suppress the change in the operation range of the wiper according to the change in the friction state of the wiping surface.

Further, according to the present invention, as in the invention described in claim 11 , the predicted voltage is a voltage required according to the number of revolutions of the motor, a voltage required according to the inertia of the wiper that reciprocates, and It was calculated | required by adding the voltage required according to the friction state with respect to the said wiper of the said wiping surface.

Therefore, according to the eleventh aspect, it is possible to accurately predict the predicted voltage supplied to the motor when the wiper is reciprocated.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Hereinafter, a case will be described in which the present invention is applied to a wiper device that is mounted on a vehicle and reciprocally moves two wipers individually by two motors.

  FIG. 1 shows a schematic configuration of a wiper device 10 according to the present embodiment.

  As shown in the figure, the wiper device 10 is not shown by rotating and driving two wipers 16A and 16B, two pivots 22A and 22B rotatably held, and a rotating shaft not shown. Two motors 12A and 12B that respectively rotate the pivots 22A and 22B via gears and the like are provided.

  The wipers 16A and 16B include a wiper blade 17 and a wiper arm 18 and the like. One end of the wiper arm 18 is fixed to the pivots 22A and 22B, respectively, and the wipers 16A and 16B rotate around the one end of the wiper arm 18 as the pivots 22A and 22B rotate.

  The wiper device 10 according to the present embodiment is configured to reciprocate the wipers 16A and 16B by rotating and rotating the pivots 22A and 22B so that the rotation shafts of the motors 12A and 12B reciprocate. The windshield 50 is wiped by the reciprocation of the wipers 16A and 16B.

  On the other hand, the wiper device 10 supplies voltages to the motors 12A and 12B to drive the motors 12A and 12B, and controls the voltages supplied from the drive devices 24A and 24B to the motors 12A and 12B. An ECU (Electronic Control Unit) 26 and angle sensors 28A and 28B for detecting the positions of the wipers 16A and 16B within the reciprocating operation range are provided.

  The angle sensors 28A and 28B have an operation range in which the wipers 16A and 16B reciprocate as positions of the wipers 16A and 16B, a lower inversion position that is one end within the operation range, and a lower inversion position that is the other inversion upper position. The angle θ of the wiper arm 18 is detected as a reference (θ = 0 °), and angle information indicating the detected angle θ is output to the ECU 26.

  The driving devices 24A and 24B are supplied with a pulse width modulation signal as a control signal for controlling the driving of the motors 12A and 12B from the ECU 26, and supply a voltage corresponding to the duty ratio of the pulse width modulation signal. Then, the motors 12A and 12B are driven.

  The ECU 26 includes an arithmetic processing unit 40, a RAM 42, a ROM 44, a nonvolatile memory 46, and the like.

  The ROM 44 stores in advance a drive control program for controlling the drive of the wipers 16A and 16B by controlling the rotational drive of the motors 12A and 12B.

  The nonvolatile memory 46 stores a duty of a pulse width modulation signal indicating a predicted voltage that is predicted to be supplied to the motors 12A and 12B when the wipers 16A and 16B are reciprocated for each angle θ of the wipers 16A and 16B. The ratio is stored in advance for each friction state of the windshield 50 when the windshield 50 is wet (Wet state) and when the windshield 50 is dry (Dry state).

  The ECU 26 individually controls the operations of the wipers 16A and 16B, controls the pulse width modulation signal output to the driving device 24A based on the angle θ detected by the angle sensor 28A, and is detected by the angle sensor 28B. The pulse width modulation signal output to the driving device 24B is controlled based on the angle θ.

  When the ECU 26 reciprocates the wipers 16A and 16B, the ECU 26 sets the duty ratio for each angle θ for each friction state of the windshield 50 stored in the nonvolatile memory 46 to the predicted angle θ of the wipers 16A and 16B. The read duty ratio is sequentially read out, the read duty ratio is corrected according to the difference between the predicted angle θ and the angle θ detected by the angle sensors 28A and 28B, and the pulse width modulation signal having the corrected duty ratio is output to the driving devices 24A and 24B. To control the voltage supplied to the motors 12A and 12B.

  Further, the ECU 26 determines whether the windshield 50 is based on the difference between the duty ratio of the output pulse width modulation signal and the duty ratio corresponding to the angle θ detected by the angle sensors 28A and 28B stored in the nonvolatile memory 46. The friction state with respect to the wipers 16A and 16B is estimated.

  2A shows an example of the duty ratio of the pulse width modulation signal for each angle θ of the wipers 16A and 16B when the windshield 50 stored in the nonvolatile memory 46 is wet (Wet state). FIG. 2B shows a pulse width modulation signal for each angle θ of the wipers 16A and 16B when the windshield 50 stored in the nonvolatile memory 46 is dry (Dry state). An example of the duty ratio is shown.

  Next, a procedure for obtaining the duty ratio for each angle θ will be described.

  Assuming that the wipers 16A and 16B are in an ideal operating state, the voltage required for the motors 12A and 12B to reciprocate the wipers 16A and 16B is the voltage required according to the rotational speed of the motors 12A and 12B. The voltage required according to the inertia (inertia) of the reciprocating motors 12A and 12B and the voltage required according to the friction state with respect to the windshield 50 wipers 16A and 16B can be divided.

The voltage V ₁ required according to the rotational speeds of the motors 12A and 12B is proportional to the rotational speed N if the torques of the motors 12A and 12B are constant. Here, when the inclination of the rotational speed N with respect to the voltage is K _V , the voltage V ₁ can be expressed as the following equation (1).

Further, the voltage V ₂ required in accordance with the inertia can be obtained by converting the inertia torque T ₂ to the current I ₂ , and the current and the voltage are in a proportional relationship if the rotation speed is constant. . The ratio of torque _{T 2} for current _{I 2} and _{K T,} the motor 12A, and 12B winding resistance and k, motor 12A, the angular acceleration of the 12B of the rotating shaft ^{α (= dN / dt = d} 2 θ / dt 2 ), and the motor 12A, not shown in the armature and the wiper blade 17 of 12B, when the sum of the inertia of such a wiper arm 18 and J, the voltage V ₂ can be expressed as the following equation (2).

Further, the voltage V ₃ required according to the friction can be obtained from the friction torque T ₃ as in the case of inertia. Here, the friction torque T _3, when the length r of the pressing pressure F and the wiper arm 18 of the wiper blade 17 against the windshield 50 as determined by the friction coefficient mu, the voltage V _3, the following equation (3) Can be shown as: Note that the friction coefficient μ varies depending on the speed (rotational speed N) from the static friction coefficient to the dynamic friction coefficient.

The voltage V can be obtained by obtaining the sum of the voltages V _{1 to} V ₃ obtained by the above equations (1) to (3).

FIG. 3A shows the voltages V _{1 to} V ₃ and the voltage V when the windshield 50 is in the wet state by the duty ratio of the pulse width modulation signal. FIG. The voltages V _{1 to} V ₃ and the voltage V when the glass 50 is in the Dry state are indicated by the duty ratio of the pulse width modulation signal.

  In the present embodiment, the voltage V for each angle θ when the windshield 50 is in the wet state and in the dry state is obtained as the duty ratio of the pulse width modulation signal and is shown in FIGS. Remember as shown.

  Next, the operation of the wiper device 10 according to the present embodiment will be described.

  When an operation changeover switch (not shown) is turned on, the wiper device 10 rotates the motors 12A and 12B to reciprocate the wipers 16A and 16B, respectively.

  FIG. 4 shows a flow of processing of the drive control program executed by the arithmetic processing unit 40 when the operation changeover switch is turned on. The process for controlling the pulse width modulation signal output to the drive device 24A based on the angle θ detected by the angle sensor 28A by the drive control program according to the present embodiment, and the angle θ detected by the angle sensor 28B. The processing for controlling the pulse width modulation signal to be output to the driving device 24B based on this is the same processing. Therefore, hereinafter, only the processing part for controlling the pulse width modulation signal output to the driving device 24A will be described, and the description of the processing part for controlling the pulse width modulation signal output to the driving device 24B will be omitted.

  In step 100 in the figure, initial setting of the operation mode is performed. In this embodiment, the operation mode is initially set to the Dry mode.

  In the next step 102, control processing of the motor 12A is performed.

  FIG. 5 is a block diagram schematically showing the processing content of the control processing of the motor 12A.

  When the ECU 26 reciprocates the wiper 16A, the lower inversion position within the operating range of the wiper 16A is θ = 0 °, and the lower inversion position is set to time = 0 [sec] for each reciprocation once. Accordingly, the predicted angle θ of the wiper 16A is generated as the command angle θ. Further, the ECU 26 receives angle information indicating the angle θ of the wiper 16A detected by the angle sensor 28A.

  The ECU 26 reads the duty ratio of the wet state corresponding to the command angle θ from the non-volatile memory 46 when the operation mode is the wet mode, and when the operation mode is the dry mode, the ECU 26 reads Dry according to the command angle θ from the non-volatile memory 46. Read the duty ratio of the state.

  Further, the ECU 26 subtracts the angle θ of the wiper 16A from the generated command angle θ to obtain a difference, corrects the read duty ratio according to the difference, and outputs a pulse width modulation signal having the corrected duty ratio to the driving device 24A. Output to. In the present embodiment, as shown in FIG. 5, the difference obtained by multiplying the read duty ratio by subtracting the angle θ of the wiper 16A from the command angle θ by a predetermined coefficient (Kp) and the difference. The correction is performed by adding a value obtained by multiplying the integral value obtained by integrating the wiper 16A during a single reciprocation of the wiper 16A by a predetermined coefficient (Ki).

  The drive device 24A supplies a voltage corresponding to the duty ratio of the input pulse width modulation signal to drive the motor 12A.

  As shown in FIG. 1, the ECU 26 may detect the power supply voltage of the power supply that supplies power to the driving devices 24 </ b> A and 24 </ b> B, and correct the read duty ratio according to the detected change in the power supply voltage. Thereby, even if the power supply voltage changes suddenly, the wipers 16A and 16B can be controlled to the target operating state.

  In the next step 104, it is determined whether or not the operation mode is the wet mode. If the determination is affirmative, the process proceeds to step 106. If the determination is negative, the process proceeds to step 108.

  In step 106, it is determined whether or not the value obtained by subtracting the duty ratio of the wet state corresponding to the command angle θ from the duty ratio of the output pulse width modulation signal is equal to or greater than a positive threshold value. Shifts to step 110, while if negative determination is made, shifts to step 112.

  On the other hand, in step 108, it is determined whether or not the value obtained by subtracting the duty ratio of the output pulse width modulation signal from the duty ratio in the Dry state corresponding to the command angle θ is equal to or less than a negative threshold value, which is an affirmative determination. If YES, the process proceeds to step 112. If NO is determined, the process proceeds to step 110.

  In step 110, the operation mode is set to the Dry mode.

  On the other hand, in step 112, the operation mode is set to the Wet mode.

  That is, the coefficient of friction μ between the windshield 50 and the wiper 16A is larger when the windshield 50 is dry (Dry state) than when it is wet (Wet state).

  For this reason, the duty ratio of the output pulse width modulation signal is larger in the Dry state than in the Wet state.

  Therefore, in the present embodiment, a threshold value is defined between the duty ratio in the wet state and the duty ratio in the dry state, and the duty ratio of the pulse width modulation signal is determined according to the command angle θ as shown in FIG. When the value obtained by subtracting the duty ratio in the wet state is equal to or greater than a positive threshold value, it is estimated that the windshield 50 is drying and the operation mode is shifted to the Dry mode, as shown in FIG. When the value obtained by subtracting the duty ratio of the pulse width modulation signal output from the duty ratio of the Dry state corresponding to the command angle θ is equal to or less than a negative threshold value, it is estimated that the windshield 50 is getting wet. The mode is shifted to the Wet mode.

  As a result, when the windshield 50 becomes dry and the friction of the windshield 50 on the wiper 16A increases, the voltage supplied to the motor 12A increases. It can suppress that an operating speed changes.

  In the next step 114, it is determined whether or not an operation changeover switch (not shown) that controls the operation of the wiper device 10 is turned off. If a negative determination is made, the process proceeds to step 102, whereas an affirmative determination is made. Terminates this drive control program.

  As described above, according to the present embodiment, the difference between the voltage actually supplied to the motor 12A and the predicted voltage predicted to be supplied to the motor stored in advance for each position within the operating range of the wiper 16A. Since the friction state of the windshield 50 can be estimated based on the above, the wiper operation can be suppressed in consideration of the friction state of the windshield 50.

  In the present embodiment, since the friction state of the windshield 50 is estimated from the duty ratio of the pulse width modulation signal, the friction state is estimated regardless of the angle of the wiper 16A, and the operation mode is switched. Therefore, the response of the wiper 16A to the change in the friction state is improved.

  In the above-described embodiment, for example, the wipers 16A and 16B may be operated in a three-stage driving mode of high, low, and intermittent by using the operation changeover switch. In this case, the duty ratio of the pulse width modulation signal for each friction state of the windshield 50 may be stored in the nonvolatile memory 46 for each drive mode.

  Moreover, in the said embodiment, you may control so that the angle range in which the rotating shaft of motor 12A, 12B reciprocates rotates so that the magnitude | size of the friction with respect to wiper 16A, 16B of the windshield 50 is large. Thereby, it can suppress that the operating range of wiper 16A, 16B changes according to the change of the friction state of the windshield 50. FIG.

  In the present embodiment, the case where the present invention is applied to a wiper device that individually reciprocates two wipers by two motors has been described. However, the present invention is not limited to this. This type of wiper may be applied to a wiper device that is driven by a single motor using a link mechanism. Alternatively, two ECUs 26 may be provided, and each may individually apply a pulse width modulation signal to the driving devices 24A and 24B, thereby applying the wiper device that individually controls the wipers 16A and 16B.

  In the present embodiment, the case where the duty ratio of the pulse width modulation signal for each angle θ of the wipers 16A and 16B is stored in the nonvolatile memory 46 has been described. However, the present invention is not limited to this. Instead, for example, the duty ratio of the pulse width modulation signal may be stored in accordance with the total number of rotations of the motors 12A and 12B when reciprocating with the lower inversion position set to the number of rotations = 0.

  In addition, the structure (refer FIG. 1) of the wiper apparatus 10 demonstrated by the said embodiment is an example, and it cannot be overemphasized that it can change suitably in the range which does not deviate from the main point of this invention.

  The processing flow of the drive control program (see FIG. 4) described in the above embodiment is also an example, and it is needless to say that it can be appropriately changed without departing from the gist of the present invention.

  The wiper device 10 described in each of the above embodiments is mounted on a vehicle and wipes raindrops attached to the windshield 50 by reciprocating the wipers 16A and 16B. It is not limited to. That is, the object to be wiped is not limited to the windshield 50, and the object to be wiped is not limited to raindrops.

It is a block diagram which shows the structure of the wiper apparatus which concerns on embodiment. (A) is a schematic diagram illustrating an example of the duty ratio of the pulse width modulation signal for each angle θ in the wet state, and (B) is a schematic diagram illustrating an example of the duty ratio of the pulse width modulation signal in the dry state. It is. (A) is a graph showing the voltages V _{1 to} V ₃ and the voltage V in the wet state by the duty ratio of the pulse width modulation signal, and (B) is a voltage V _{1 to} V _{3 in the} dry state. And a graph showing the voltage V as a duty ratio of the pulse width modulation signal. It is a flowchart which shows the flow of a process of the drive control program which concerns on embodiment. It is the block diagram which showed typically the processing content of the control processing of the motor which concerns on embodiment. (A) is a graph showing an example of shifting from the Wet mode to the Dry mode, and (B) is a graph showing an example of shifting from the Dry mode to the Wet mode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Wiper apparatus, 12A, 12B ... Motor, 16A, 16B ... Wiper, 17 ... Wiper blade, 18 ... Wiper arm, 22A, 22B ... Motor, 24A, 24B ... Drive apparatus (supply means), 28A, 28B ... Angle sensor (Detection means), 40 ... arithmetic processing unit (control means), 46 ... non-volatile memory (storage means), 50 ... windshield (wiping surface)

Claims (11)

A motor for reciprocating the wiper;
Detecting means for detecting the position of the wiper within an operating range in which the wiper reciprocates;
Storage means for preliminarily storing predicted voltage information indicating a predicted voltage that is predicted to be supplied to the motor when the wiper is reciprocated for each position within the operation range of the wiper;
Control means for controlling the voltage supplied to the motor when reciprocating the wiper;
Wiping wiped by the reciprocating operation of the wiper based on the difference between the voltage supplied to the motor by the control of the control means and the predicted voltage indicated by the predicted voltage information corresponding to the position detected by the detecting means. Estimating means for estimating a friction state of the surface with respect to the wiper;
Equipped with a,
The storage means stores, in advance, a plurality of predicted voltage information and a threshold value of the difference in which the friction state of the wiping surface is different for each position within the operation range of the wiper,
The said estimation means is a wiper apparatus which estimates the friction state with respect to the said wiper of the said wiping surface based on the result of having compared the difference between the voltage supplied to the said motor, and the predicted voltage shown by each prediction voltage information with the said threshold value . The predicted voltage information indicates the predicted voltage when the wiper is reciprocated when the friction state of the wiping surface is a predetermined state.
The wiper device according to claim 1, wherein the estimating means estimates that the friction state of the wiping surface is different from the predetermined state when the difference is greater than or equal to a predetermined amount. The control unit reads the predicted voltage information for each position within the operation range stored in the storage unit in the order of the predicted position of the wiper when the wiper reciprocates. the predicted voltage indicated by the information is corrected according to the difference between the position detected by the position and the detection means which is the predicted, controlled as corrected predicted voltage is supplied to the motor according to claim 1 or claim claim 2 Symbol mounting of the wiper device. A supply means for supplying a voltage corresponding to the duty ratio of the input pulse width modulation signal to the motor;
The predicted voltage information indicates the predicted voltage by a duty ratio of the pulse width modulation signal,
The control unit reads the predicted voltage information for each position within the operation range stored in the storage unit in the order of the predicted position of the wiper when the wiper reciprocates. The duty ratio indicated by the information is corrected according to the difference between the predicted position and the position detected by the detection means, and the pulse width modulation signal having the corrected duty ratio is output to the supply means. the wiper apparatus according to claim 1 or claim 2, wherein controlling the voltage supplied to the motor. The control means adds a value obtained by multiplying the difference by a predetermined coefficient to a duty ratio indicated by the read predicted voltage information, and a value obtained by multiplying the integral value obtained by integrating the difference by a predetermined coefficient. The wiper device according to claim 4, wherein the correction is performed by the following. It said control means detects a power supply voltage, the detected wiper device according to claim 4 or claim 5, wherein correcting the duty ratio indicated by the predicted voltage information in response to a change in power supply voltage. The estimation means includes a duty ratio of the pulse width modulation signal output by the control means and a duty ratio indicated by predicted voltage information stored in the storage means and corresponding to a position detected by the detection means. The wiper device according to any one of claims 4 to 6 , wherein the friction state is estimated based on a difference. A motor for reciprocating the wiper;
Detection means for detecting the position of the wiper within the operating range in which the wiper reciprocates; and for each position within the operating range of the wiper, the wiper is predicted to be supplied to the motor when the wiper is reciprocated. Storage means for storing predicted voltage information indicating the predicted voltage in advance;
When reciprocating the wiper, the predicted voltage information for each position within the operation range stored in the storage means is read in the order of the predicted position of the wiper, and the prediction indicated by the read predicted voltage information Control means for correcting the voltage according to the difference between the predicted position and the position detected by the detection means, and controlling the corrected predicted voltage to be supplied to the motor;
Wiping wiped by the reciprocating operation of the wiper based on the difference between the voltage supplied to the motor by the control of the control means and the predicted voltage indicated by the predicted voltage information corresponding to the position detected by the detecting means. Estimating means for estimating a friction state of the surface with respect to the wiper;
Equipped with a,
The storage means stores, in advance, a plurality of predicted voltage information and a threshold value of the difference in which the friction state of the wiping surface is different for each position within the operation range of the wiper,
The said estimation means is a wiper apparatus which estimates the friction state with respect to the said wiper of the said wiping surface based on the result of having compared the difference between the voltage supplied to the said motor, and the predicted voltage shown by each prediction voltage information with the said threshold value . Wherein, one of claims 1 to 8 for controlling so as to increase the voltage supplied as the motor the magnitude of the friction against the wiper of the wiping surface estimated by the estimating means The wiper device according to claim 1. The motor reciprocates the wiper by reciprocating a rotating shaft,
Said control means of claims 1 to 9 for controlling so as the rotating shaft is large magnitude of friction against the wiper of the wiping surface estimated by the estimating means to widen the angular range of reciprocal rotation The wiper device according to any one of the preceding claims. The predicted voltage is a voltage required according to the number of rotations of the motor, a voltage required according to the inertia of the wiper that reciprocates, and a voltage required according to the friction state of the wiping surface with respect to the wiper. The wiper device according to any one of claims 1 to 10 , wherein the wiper device is obtained by adding.

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