Wipe device

Abstract

To provide a wipe device which can prevent an abnormal behavior of a wiper blade in switching a wipe range.SOLUTION: A wipe device which uses a predetermined power source to reciprocatingly move a wiper blade to wipe rain water on a surface to be wiped, includes a drive circuit which drives the power source, and a control part which controls the drive circuit. The control part controls a wipe range to be switched when the wiper blade is in an upper reverse position.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a wiping device. [Background technology]

[0002] Patent Document 1 discloses a vehicle wiper control device that selectively and intensively wipes away dirt and the like. This vehicle wiper control device includes a DC motor device for causing a wiper blade member to slide back and forth along the surface of a car window glass member, a motor rotation control means for controlling the rotation of the DC motor device, a power supply line arranged in a bridge circuit for supplying power to the DC motor device, a current detection means for detecting a current flowing through the power supply line while the wiper blade member slides, and a current displacement detection means for detecting whether the displacement amount per unit time of the detection value by the current detection means exceeds a predetermined threshold value, and the motor rotation control means switches the rotation direction of the DC motor device so that the wiper blade member repeatedly slides over the portion detected by the current displacement detection means.

[0003] According to this vehicle wiper control device, the rotation direction of the DC motor device is switched between forward and reverse so that the wiper blade member repeatedly slides over the detection portion of the current displacement detection means, making it possible to selectively and intensively wipe away only the dirt and other particles adhering to the car window glass member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-082104 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned background art, the wiping range of the wiper blade when the wiper blade member (wiper blade) repeatedly slides over the detection portion of the current displacement detection means is different from the normal wiping range. That is, the wiping range when selectively and intensively wiping off the dirty portions is narrower than the normal wiping range. In this way, abnormal behavior of the wiper blade may occur when the wiping range is switched.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide a wiping device that is capable of suppressing abnormal behavior of the wiper blade when switching the wiping range. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the present invention adopts, as a first solution relating to a wiping device, a wiping device that wipes rainwater from a surface to be wiped by reciprocating a wiper blade using a predetermined power source, the wiping device including a drive circuit that drives the power source and a control unit that controls the drive circuit, and the control unit switches the wiping range at a timing when the target speed is zero both before and after the switch.

[0008] In the present invention, as a second solution related to the wiping device, a means is adopted in which, in the above-mentioned first solution, the wiping range is a normal wiping range in normal mode and a narrow wiping range in heavy rain mode that is narrower than the normal wiping range.

[0009] In the present invention, as a third solution related to the wiping device, the second solution described above is adopted in which the control unit performs the switching from the normal mode to the heavy rain mode when the wiper blade is in the upper reversal position.

[0010] The present invention employs, as a fourth solving means related to the wiping device, any one of the first to third solving means, in which the power source is a brushless motor. Effect of the Invention

[0011] According to the present invention, it is possible to provide a wiping device capable of suppressing abnormal behavior of the wiper blade member when switching the wiping range. [Brief description of the drawings]

[0012] [Figure 1] 1 is a block diagram showing a functional configuration of a wiping device according to a first embodiment of the present invention. [Diagram 2] 4 is a first flowchart showing the operation of the wiping device according to the first embodiment of the present invention. [Diagram 3] 5 is a waveform diagram showing the operation of the wiping device according to the first embodiment of the present invention. FIG. [Figure 4] 5A to 5C are reference views relating to the operation of the wiping device according to the first embodiment of the present invention. [Diagram 5] FIG. 6 is a block diagram showing a functional configuration of a wiping device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] [First embodiment] First, a first embodiment of the present invention will be described with reference to Figures 1 to 4. A wiping device A according to the first embodiment is mounted on various types of mobile vehicles such as gasoline-powered automobiles, hybrid automobiles, and electric automobiles, and is a device for wiping rainwater adhering to the surface (wiped surface W) of a member to be wiped such as a windshield or rear windshield.

[0014] 1, the wiping device A according to the first embodiment includes a pair of wiper blades 1d, 1p, a pair of wiper arms 2d, 2p, a link mechanism 3, a motor 4 (power source), an angle detection circuit 5, a control unit 6, and a drive circuit 7. In addition, the control unit 6 includes a ROM (Read Only Memory) 61, a RAM (Random Access Memory) 62, and a CPU (Central Processing Unit) 63 as shown in the figure.

[0015] This wiping device A employs a single motor drive system in which a pair of wiper blades 1d, 1p are driven by a single motor 4 (power source) by mechanically connecting a pair of wiper arms 2d, 2p with a link mechanism 3. In other words, this wiping device A is provided with one power source, and the pair of wiper blades 1d, 1p are simultaneously reciprocated by the single power source. In addition, this wiping device A employs a parallel wiping system in which the pair of wiper blades 1d, 1p move in the same direction as shown in FIG. 1.

[0016] Here, in the symbols in Fig. 1, "d" indicates members and parts related to the driver's seat side of the vehicle. Also, "p" indicates members and parts related to the passenger's seat side of the vehicle. In Fig. 1, symbol Rd indicates the wiping range of wiper blade 1d on the driver's seat side when the operation mode of wiping device A is set to the normal mode (driver's seat normal wiping range). Also, symbol Rp indicates the wiping range of wiper blade 1p on the passenger's seat side when the operation mode is set to the normal mode (passenger's seat normal wiping range).

[0017] The driver's seat normal wiping range Rd is a range from the lower reversal position PLd to the upper reversal position PUd as the movement trajectory of the driver's seat side wiper blade 1d. The lower reversal position PLd is a position where the driver's seat side wiper blade 1d switches from a downward motion to an upward motion on the wiped surface W. The upper reversal position PUd is a position where the driver's seat side wiper blade 1d switches from an upward motion to a downward motion on the wiped surface W.

[0018] The passenger side normal wiping range Rp is a range from the lower reversal position PLp to the upper reversal position PUp as the movement trajectory of the passenger side wiper blade 1p. The lower reversal position PLp is a position where the passenger side wiper blade 1p switches from a downward motion to an upward motion on the wiped surface W. The upper reversal position PUp is a position where the passenger side wiper blade 1p switches from an upward motion to a downward motion on the wiped surface W.

[0019] Although details will be described later, this wiping device A has a heavy rain mode as an operation mode different from the normal mode. This heavy rain mode is an operation mode in which the wiping range is narrower than the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp in the normal mode. In other words, the heavy rain mode is an operation mode in which the wiping range is narrower than the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp in the normal mode, and the reciprocating speed is faster than in the normal mode.

[0020] For example, the wiping range in the heavy rain mode has an upper inverted position that is the same as the upper inverted positions PUd, PUp of the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp, but has a lower inverted position that is higher (lower inverted positions QLd, QLp) than the lower inverted positions PLd, PLp of the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp. The wiping range in the heavy rain mode is, for example, the forward visibility "A zone" set by regulations.

[0021] Here, "A Zone" refers to the area equivalent to "A Area" in the wipe-out area regulations of Japan and the European Economic Community (EEC) and "C Area" in the wipe-out area regulations of the US Federal Motor Vehicle Safety Standards (FMVSS).

[0022] As shown in the figure, the pair of wiper blades 1d, 1p are rod-shaped members arranged on the surface to be wiped W. The pair of wiper blades 1d, 1p abut against the surface to be wiped W, and wipe away rainwater present on the surface to be wiped W by performing a reciprocating motion (oscillating motion) on the surface to be wiped W. The pair of wiper blades 1d, 1p is mechanically connected to a motor 4 via a pair of wiper arms 2d, 2p.

[0023] That is, the wiper blade 1d on the driver's side is connected to the motor 4 via a wiper arm 2d provided on the driver's side. The wiper blade 1p on the passenger's side is connected to the motor 4 via a wiper arm 2p and a link mechanism 3 provided on the passenger's side.

[0024] As shown in the figure, the pair of wiper arms 2d, 2p are rod-shaped members, one end of which is connected to the intermediate position of the pair of wiper blades 1d, 1p, and the other end of which is connected to the pair of wiper shafts Td, Tp. That is, the wiper arm 2d on the driver's seat side has one end connected to the intermediate position of the wiper blade 1d on the driver's seat side, and the other end connected to the wiper shaft Td on the driver's seat side.

[0025] On the other hand, one end of the passenger side wiper arm 2p is connected to the middle position of the passenger side wiper blade 1p, and the other end is connected to the passenger side wiper shaft Tp. Note that such a pair of wiper arms 2d, 2p are members included in the components of the pair of wiper blades 1d, 1p.

[0026] The pair of wiper arms 2d, 2p function as power transmission components that mechanically transmit the rotational force of the motor 4 to the pair of wiper blades 1d, 1p. The pair of wiper arms 2d, 2p also function as biasing members that press the pair of wiper blades 1d, 1p against the surface W to be wiped with a predetermined pressing force.

[0027] The link mechanism 3 is a mechanical component that is mechanically connected to the other ends of the pair of wiper arms 2d, 2p and is also connected to the output shaft of a motor 4. The link mechanism 3 has a support shaft fixed to the vehicle and is rotatable around the support shaft. The output shaft of the motor 4 is connected to the link mechanism 3, and by manipulating the rotation angle of the link mechanism 3, the pair of wiper blades 1d, 1p are swung on the surface W to be wiped. The motor 4 is a predetermined power source in the first embodiment.

[0028] The angle detection circuit 5 outputs an angle signal proportional to the rotation angle of the motor 4 to the CPU 63. This angle signal is a signal indicating the operating angle of the pair of wiper blades 1d, 1p mechanically connected by the link mechanism 3. In detail, such an angle signal is composed of a relative position signal indicating the relative position of the pair of wiper blades 1d, 1p and an absolute position signal indicating the absolute position of the pair of wiper blades 1d, 1p.

[0029] The relative position signal is a pulse signal (motor pulse) generated with the rotation of the motor 4, and is a pulse signal (pulse train) with a number of pulses proportional to the rotation angle of the motor 4. In contrast, the absolute position signal is a single pulse signal generated when the pair of wiper blades 1d, 1p reach a control reference position. The control reference position is, for example, the bottom reversal positions PLd, PLp.

[0030] The control unit 6 has two control modes, a normal mode and a heavy rain mode, and generates a drive command corresponding to the operation mode by performing a control process corresponding to the operation mode. The control unit 6 outputs the drive command to the drive circuit 7 to control the movement of the pair of wiper blades 1d, 1p.

[0031] The normal mode is a control mode for the pair of wiper blades 1d, 1p for normal rainfall. When the normal mode is instructed by a switch signal input from a higher-level control device, the control unit 6 generates a drive command according to the normal mode and outputs it to the drive circuit 7. The switch signal is a higher-level control command that instructs the wiping device A to turn on / off the wiper switch provided on the vehicle, specify the heavy rain mode, turn on / off the mist switch, intermittent operation (Lo, Hi, INT), etc.

[0032] On the other hand, the heavy rain mode is a control mode for the pair of wiper blades 1d, 1p for a sudden heavy rain. When the heavy rain mode is instructed by the switch signal, the control unit 6 generates a drive command according to the heavy rain mode and outputs it to the drive circuit 7.

[0033] In controlling the pair of wiper blades 1d, 1p, the control unit 6 refers to a switch signal input from a higher-level control device and an angle signal input from the angle detection circuit 5. That is, the control unit 6 feedback-controls the pair of wiper blades 1d, 1p based on the switch signal and the angle signal.

[0034] In the control unit 6, the ROM 61 is a non-volatile memory. The ROM 61 stores a control program executed by the CPU 63 to feedback control the pair of wiper blades 1d, 1p. The ROM 61 also stores a normal mode operation map and a heavy rain mode operation map required for the CPU 63 to execute the control program.

[0035] The normal mode operation map is a control map used when the CPU 63 executes control processing (normal control processing) related to the normal mode in the control program. That is, the normal mode operation map is a group of control data indicating the time-series target speeds of the pair of wiper blades 1d, 1p in the normal mode.

[0036] On the other hand, the heavy rain mode operation map is a control map used when the CPU 63 executes control processing related to the heavy rain mode (heavy rain control processing) in the control program. That is, the heavy rain mode operation map is a group of control data indicating the time-series target speeds of the pair of wiper blades 1d, 1p in the heavy rain mode.

[0037] The RAM 62 is a volatile memory. This RAM 62 temporarily stores various data generated when the CPU 63 executes the control program. This RAM 62 temporarily stores, for example, a flag (control flag F) indicating whether the control mode being executed is the normal mode or the heavy rain mode, a counter value (wiping count value N) indicating the number of wiping operations in the control mode being executed, and the like.

[0038] The CPU 63 generates a drive command by executing a control program pre-stored in the ROM 61, and outputs this drive command to the drive circuit 7. When executing the control program, the CPU 63 refers to a switch signal input from a higher-level control device, an angle signal input from the angle detection circuit 5, and also to a normal mode operation map and a heavy rain mode operation map pre-stored in the ROM 61.

[0039] That is, the CPU 63 generates a drive command by referring to the switch signal, the angle signal, and the normal mode operation map and the heavy rain mode operation map based on the control program. This drive command is a control command to instruct the drive circuit 7 to drive the pair of wiper blades 1d, 1p according to the control mode (normal mode or heavy rain mode), and is also a control command to make the moving speed of the pair of wiper blades 1d, 1p obtained from the angle signal equal to the target speed indicated by the normal mode operation map or the heavy rain mode operation map.

[0040] The drive circuit 7 generates a drive signal based on a drive command input from the CPU 63 (controller 6) and outputs the drive signal to the motor 4. The drive circuit 7 is, for example, an inverter circuit including a plurality of switching transistors. In this case, the drive command is a PWM (Pulse Width Modulation) signal whose duty ratio is variably set according to the deviation between the target speed and the moving speed of the pair of wiper blades 1d, 1p.

[0041] Next, a characteristic operation of the wiping device A according to the first embodiment will be described with reference to the flowchart shown in Fig. 2. Note that this flowchart shows the procedure of control processing in the CPU 63 (control unit 6).

[0042] First, the CPU 63 recognizes the operation mode instructed by the upper control device by referring to a switch signal input from the upper control device (step S1). Then, the CPU 63 performs each process of the following steps S2 to S10 based on the recognition in step S1.

[0043] That is, the CPU 63 judges whether or not the heavy rain mode has been instructed by the upper control device (step S2). If the judgment in step S2 is "No", that is, if the normal mode has been instructed by the upper control device, the CPU 63 judges whether or not the wipe in the normal mode is the first wipe (initial wipe) by referring to the wipe count value N (step S3).

[0044] If the determination in step S3 is "No," that is, if the wiping in the normal mode is not the initial wiping, the CPU 63 ends the process. On the other hand, if the determination in step S3 is "Yes," that is, if the wiping in the normal mode is the initial wiping, the CPU 63 determines whether the operating angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, PUp by referring to the angle signal (step S4).

[0045] If the determination in step S4 is "No," that is, if the operation angles of the pair of wiper blades 1d, 1p have not reached the upper reversal positions PUd, PUp, the CPU 63 ends the process. On the other hand, if the determination in step S4 is "Yes," that is, if the operation angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, PUp, the CPU 63 switches the control map used for generating the drive command to the normal mode operation map (step S5).

[0046] For example, when the wiping device A is operating in the heavy rain mode, the control map is switched from the heavy rain mode operation map to the normal mode operation map in step S5. Then, by switching the control map from the heavy rain mode operation map to the normal mode operation map, the CPU 63 sets the control mode to the normal mode (step S6).

[0047] That is, when the process of step S6 is completed, the CPU 63 performs a process of generating a drive command based on the normal mode operation map. Therefore, the pair of wiper blades 1d, 1p normally wipes away rainwater by reciprocating in the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp that extend from the lower reversal positions PLd, PLp to the upper reversal positions PUd, PUp.

[0048] If the determination in step S2 is "Yes", that is, if the heavy rain mode is instructed by a higher-level control device, the CPU 63 determines whether the wipe in the heavy rain mode is the first wipe (initial wipe) by referring to the wipe count value N (step S7).

[0049] If the determination in step S7 is "No," that is, if the wiping in the heavy rain mode is not the initial wiping, the CPU 63 ends the process. On the other hand, if the determination in step S7 is "Yes," that is, if the wiping in the heavy rain mode is the initial wiping, the CPU 63 determines whether the operating angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, Pup by referring to the angle signal (step S8).

[0050] If the determination in step S8 is "No," that is, if the operation angles of the pair of wiper blades 1d, 1p have not reached the upper reversal positions PUd, PUp, the CPU 63 ends the process. On the other hand, if the determination in step S8 is "Yes," that is, if the operation angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, PUp, the CPU 63 switches the control map used for generating the drive command to the heavy rain mode operation map (step S9).

[0051] For example, when the wiping device A is operating in the normal mode, the control map is switched from the normal mode operation map to the heavy rain mode operation map in step S9. Then, by switching the control map from the normal mode operation map to the heavy rain mode operation map, the CPU 63 sets the control mode to the heavy rain mode (step S10).

[0052] That is, when the process of step S10 is completed, the CPU 63 performs a process of generating a drive command based on the operation map for the heavy rain mode. Therefore, the pair of wiper blades 1d, 1p reciprocate faster than in the normal mode in a narrow wiping range where the upper reversal positions PUd, PUp are the same as the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp, but the lower reversal positions are set to lower reversal positions QLd, QLp higher than the lower reversal positions PLd, PLp of the driver's seat normal wiping range Rd, Rp, thereby wiping rainwater faster.

[0053] Fig. 3 is a waveform diagram showing the operation of such wiping device A. In Fig. 3, (a) shows the target speed and operation angle when switching from Hi operation in normal mode to heavy rain mode. Also, in Fig. 3, (b) shows the target speed and operation angle when switching from heavy rain mode to Hi operation in normal mode.

[0054] 3(a) and 3(b), in the wiping device A according to the first embodiment, the timing for switching from the normal mode Hi operation to the heavy rain mode is set to the timing when the operation angles of the pair of wiper blades 1d, 1p reach the upper reversal positions PUd, PUp. Also, in this wiping device A, the timing for switching from the heavy rain mode to the normal mode Hi operation is set to the timing when the operation angles of the pair of wiper blades 1d, 1p reach the upper reversal positions PUd, PUp.

[0055] Fig. 4 is a reference diagram relating to the operation of the wiping device A according to the first embodiment. In Fig. 4, (a) shows the target speed and operation angle when switching from Hi operation in normal mode to heavy rain mode. Also, in Fig. 4, (b) shows the target speed and operation angle when switching from heavy rain mode to Hi operation in normal mode.

[0056] 4(a) and 4(b), in this reference example, the timing for switching from the normal mode Hi operation to the heavy rain mode is not set to the timing when the operation angles of the pair of wiper blades 1d, 1p reach the upper reversal positions PUd, PUp. Also, in this reference example, the timing for switching from the heavy rain mode to the normal mode Hi operation is not set to the timing when the operation angles of the pair of wiper blades 1d, 1p reach the upper reversal positions PUd, PUp.

[0057] In this embodiment, the wiping range in the heavy rain mode is set such that the upper inversion positions PUd, PUp are the same as the upper inversion positions PUd, PUp in the Hi operation in the normal mode, and the lower inversion positions QLd, QLp are set to positions higher than the lower inversion positions PLd, PLp in the Hi operation in the normal mode. In other words, the upper inversion positions are the same in the heavy rain mode and the normal mode, but the lower inversion positions are different.

[0058] In such a relationship between the heavy rain mode and the normal mode, the upper reversal positions PUd, PUp of the pair of wiper blades 1d, 1p are the timing when the target speeds of the pair of wiper blades 1d, 1p before and after switching are both zero. That is, the wiping device A according to the first embodiment switches the wiping range at the timing when the target speeds of the pair of wiper blades 1d, 1p before and after switching are both zero.

[0059] Such a wiping device A is a device that wipes rainwater off a wiped surface W by reciprocating a pair of wiper blades 1d, 1p using a motor 4 (power source), and is equipped with a drive circuit 7 that drives the motor 4 (power source) and a control unit 6 that controls the drive circuit 7, and the control unit 6 switches the wiping range at a timing when the target speeds before and after the switch are both zero.

[0060] According to this first embodiment, the control map (operation mode) is switched, i.e., the wiping range is switched, at a timing when the target speed is zero both before and after the switch, so it is possible to provide a wiping device A that can suppress abnormal behavior of a pair of wiper blades 1d, 1p when the control map (operation mode) is switched, i.e., when the wiping range is switched.

[0061] In addition, according to the first embodiment, the wiping range of a pair of wiper blades 1d, 1p is set to a normal wiping range in normal mode and a wiping range in heavy rain mode that is narrower than the normal wiping range, so that abnormal behavior of the pair of wiper blades 1d, 1p can be suppressed when switching between the normal mode and the heavy rain mode.

[0062] Furthermore, according to the first embodiment, the control unit 6 switches between normal mode and heavy rain mode at the upper reversal positions PUd, PUp, where the target speeds are both zero before and after the switch, so that it is possible to effectively suppress abnormal behavior of the pair of wiper blades 1d, 1p when switching between normal mode and heavy rain mode.

[0063] Furthermore, according to the first embodiment, the motor 4 (power source) simultaneously reciprocates the pair of wiper blades 1d, 1p, so that in the wiping device A which is driven by a single motor, it is possible to suppress abnormal behavior of the pair of wiper blades 1d, 1p.

[0064] Second Embodiment A second embodiment of the present invention will be described with reference to Fig. 5. A wiping device B according to the second embodiment, like the wiping device A according to the first embodiment, is mounted on various vehicles and wipes rainwater off the surface (wiped surface W) of a windshield or a rear windshield. In Fig. 5, the same components as those in the first embodiment are denoted by the same reference numerals.

[0065] This wiping device B is equipped with a drive control device 10 as shown in Fig. 5. As shown in the figure, this drive control device 10 is equipped with a pair of motors 4d, 4p and a pair of wiper drive control units 10d, 10p. In other words, this wiping device B is a dual-motor drive type wiping device. In addition, this wiping device B employs an opposed wiping type in which a pair of wiper blades 1d, 1p move opposite each other as shown in Fig. 5.

[0066] The motor 4d on the driver's seat side includes a motor body 8d and a speed reduction mechanism 9d. The motor 4p on the passenger's seat side includes a motor body 8p and a speed reduction mechanism 9p. A pair of wiper drive controllers 10d and 10p drive and control the pair of motors 4d and 4p, which are power sources.

[0067] Of the pair of wiper drive control units 10d, 10p, the first wiper drive control unit 10d is a drive control unit corresponding to the motor 4d on the driver's seat side, and is equipped with an angle detection circuit 11d, a ROM (Read Only Memory) 12d, a RAM (Random Access Memory) 13d, a communication circuit 14d, a CPU (Central Processing Unit) 15d, and a drive circuit 16d.

[0068] Further, of the pair of wiper drive control units 10d, 10p, the second wiper drive control unit 10p is a drive control unit corresponding to the motor 4p on the passenger side, and is equipped with an angle detection circuit 11p, a ROM (Read Only Memory) 12p, a RAM (Random Access Memory) 13p, a communication circuit 14p, a CPU (Central Processing Unit) 15p, and a drive circuit 16p.

[0069] The motor 4d on the driver's seat side is driven and controlled by the wiper drive control unit 10d, so that the wiper blade 1d on the driver's seat side reciprocates (oscillates) around the wiper shaft Td as a fulcrum. The motor 4p on the passenger's seat side is driven and controlled by the wiper drive control unit 10p, so that the wiper blade 1p on the passenger's seat side reciprocates (oscillates) around the wiper shaft Tp as a fulcrum.

[0070] In the first wiper drive control unit 10d, the angle detection circuit 11d has a function similar to that of the angle detection circuit 5 in the first embodiment, and outputs an angle signal proportional to the rotation angle of the motor main body 8d to the CPU 15d. This angle signal is a signal indicating the operating angle of the wiper blade 1d on the driver's seat side, and is composed of the relative position signal and absolute position signal described in the first embodiment.

[0071] The ROM 12d is a non-volatile memory. The ROM 12d stores a control program for the CPU 15d to feedback control the wiper blade 1d on the driver's side. The ROM 12d also stores a normal mode operation map and a heavy rain mode operation map required for the CPU 15d to execute the control program. The normal mode operation map and the heavy rain mode operation map indicate the target speed of the wiper blade 1d on the driver's side.

[0072] The RAM 13d is a volatile memory. This RAM 13d temporarily stores various data generated when the CPU 15d executes the control program. For example, the RAM 13d temporarily stores a flag (control flag F) indicating whether the control mode being executed is the normal mode or the heavy rain mode, a counter value (wiping count value N) indicating the number of wiping operations in the control mode being executed, and the like.

[0073] The communication circuit 14d transmits and receives control information to and from the second wiper drive control unit 10p. The communication circuit 14d receives, as the control information, for example, the current position of the wiper blade 1p on the passenger side from the communication circuit 14p of the second wiper drive control unit 10p. The communication circuit 14d also transmits, as the control information, for example, the current position of the wiper blade 1d on the driver side to the communication circuit 14p of the second wiper drive control unit 10p.

[0074] The CPU 15d generates a drive command by executing a control program previously stored in the ROM 12d, and outputs the drive command to the drive circuit 16d. When executing the control program, the CPU 15d refers to the switch signal input from the upper control device, the angle signal input from the angle detection circuit 11d, the control information input from the communication circuit 14d, and the normal mode operation map and the heavy rain mode operation map previously stored in the ROM 12d.

[0075] That is, the CPU 15d generates a drive command by referring to the switch signal, the angle signal, the control information, and the normal mode operation map and the heavy rain mode operation map based on the control program. The drive command is a control command that instructs the drive circuit 16d to drive the wiper blade 1d on the driver's seat side according to the control mode (normal mode or heavy rain mode) and takes into account the drive control state of the wiper blade 1p on the passenger's seat side in the second wiper drive control unit 10p.

[0076] In other words, this drive command controls the driver's side wiper blade 1d so that the movement speed of the driver's side wiper blade 1d obtained from the angle signal becomes equal to the target speed indicated by the normal mode operation map or the heavy rain mode operation map, and is synchronized with the movement of the passenger side wiper blade 1p.

[0077] The drive circuit 16d generates a drive signal based on a drive command input from the CPU 15d and outputs the drive signal to the motor 4d. The drive circuit 16d is, for example, an inverter circuit equipped with a plurality of switching transistors. In this case, the drive command is a PWM (Pulse Width Modulation) signal whose duty ratio is variably set according to the deviation between the target speed and the moving speed of the wiper blade 1d on the driver's seat side.

[0078] On the other hand, in the second wiper drive control unit 10p, the angle detection circuit 11p has a function similar to that of the angle detection circuit 5 in the first embodiment, and outputs an angle signal proportional to the rotation angle of the motor main body 8p to the CPU 15p. This angle signal is a signal indicating the operating angle of the passenger side wiper blade 1p, and is composed of the relative position signal and absolute position signal described in the first embodiment.

[0079] The ROM 12p is a non-volatile memory. The ROM 12p stores a control program for the CPU 15p to feedback control the passenger side wiper blade 1p. The ROM 12p also stores a normal mode operation map and a heavy rain mode operation map required for the CPU 15p to execute the control program.

[0080] These normal mode operation map and heavy rain mode operation map indicate the target speed of the wiper blade 1p on the passenger side. The control program stored in the ROM 12p is substantially the same as the control program stored in the ROM 12d of the first wiper drive control unit 10d.

[0081] The RAM 13p is a volatile memory. This RAM 13p temporarily stores various data generated when the CPU 15p executes the control program. For example, this RAM 13p temporarily stores a flag (control flag F) indicating whether the control mode being executed is the normal mode or the heavy rain mode, a counter value (wiping count value N) indicating the number of wiping operations in the control mode being executed, and the like.

[0082] The communication circuit 14p transmits and receives control information to and from the first wiper drive control unit 10d. The communication circuit 14p receives, as the control information, for example, the current position of the wiper blade 1d on the driver's seat side from the communication circuit 14d of the first wiper drive control unit 10d. The communication circuit 14p also transmits, as the control information, for example, the current position of the wiper blade 1p on the passenger's seat side to the communication circuit 14d of the first wiper drive control unit 10d.

[0083] The CPU 15p generates a drive command by executing a control program previously stored in the ROM 12p, and outputs the drive command to the drive circuit 16p. When executing the control program, the CPU 15p refers to the switch signal input from the upper control device, the angle signal input from the angle detection circuit 11p, the control information input from the communication circuit 14p, and the normal mode operation map and the heavy rain mode operation map previously stored in the ROM 12p.

[0084] That is, the CPU 15p generates a drive command by referring to the switch signal, the angle signal, the control information, and the normal mode operation map and the heavy rain mode operation map based on the control program. The drive command is a control command that instructs the drive circuit 16p to drive the passenger side wiper blade 1p according to the control mode (normal mode or heavy rain mode) and takes into account the drive control state of the driver side wiper blade 1d in the first wiper drive control unit 10d.

[0085] In other words, this drive command controls the passenger side wiper blade 1p so that the movement speed of the passenger side wiper blade 1p obtained from the angle signal becomes equal to the target speed indicated by the normal mode operation map or the heavy rain mode operation map, and is synchronized with the movement of the driver's side wiper blade 1d.

[0086] The drive circuit 16p generates a drive signal based on a drive command input from the CPU 15p and outputs the drive signal to the motor 4p. The drive circuit 16p is, for example, an inverter circuit equipped with a plurality of switching transistors. In this case, the drive command is a PWM (Pulse Width Modulation) signal whose duty ratio is variably set according to the deviation between the target speed and the moving speed of the wiper blade 1p on the passenger side.

[0087] Next, a characteristic operation of the wiping device B according to the second embodiment will be described.

[0088] In this wiping device B, a first wiper drive control unit 10d controls the rotation of a motor 4d on the driver's seat side based on a control program, so that a wiper blade 1d on the driver's seat side performs a wiping operation on a surface to be wiped W. Also, in this wiping device B, a second wiper drive control unit 10p controls the rotation of a motor 4p on the passenger's seat side based on a control program, so that a wiper blade 1p on the passenger's seat side performs a wiping operation on a surface to be wiped W.

[0089] In addition, in the wiping device B, control information of the first wiper drive control unit 10d and control information of the second wiper drive control unit 10p are exchanged with each other through a pair of communication circuits 14d and 14p, so that the wiper blade 1d on the driver's seat side and the wiper blade 1p on the passenger's seat side perform wiping operations in synchronization with each other.

[0090] The control of the driver's side wiper blade 1d by the first wiper drive control unit 10d and the control of the passenger side wiper blade 1p by the second wiper drive control unit 10p are similar, and the processing performed by the pair of wiper drive control units 10d, 10p when switching between the wiping range in heavy rain mode and the wiping range in normal mode is similar to the flowchart of Figure 2 in the first embodiment.

[0091] That is, the pair of CPUs 15d, 15p in the pair of wiper drive control units 10d, 10p recognizes the operation mode instructed by the upper control device by referring to a switch signal input from the upper control device (step S1). Then, the pair of CPUs 15d, 15p perform each process of the following steps S2 to S10 based on the recognition in step S1.

[0092] That is, the pair of CPUs 15d, 15p judges whether or not the heavy rain mode has been instructed from the upper control device (step S2). Then, if the judgment in step S2 is "No", that is, if the normal mode has been instructed from the upper control device, the pair of CPUs 15d, 15p judges whether or not the wipe in the normal mode is the first wipe (initial wipe) by referring to the wipe count value N (step S3).

[0093] If the determination in step S3 is "No," that is, if the wiping in the normal mode is not the initial wiping, the pair of CPUs 15d, 15p terminate the process. On the other hand, if the determination in step S3 is "Yes," that is, if the wiping in the normal mode is the initial wiping, the pair of CPUs 15d, 15p refer to the angle signal to determine whether the operating angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, Pup (step S4).

[0094] If the determination in step S4 is "No," that is, if the operation angles of the pair of wiper blades 1d, 1p have not reached the upper reversal positions PUd, PUp, the pair of CPUs 15d, 15p terminate the process. On the other hand, if the determination in step S4 is "Yes," that is, if the operation angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, PUp, the pair of CPUs 15d, 15p switch the control map used for generating the drive command to the normal mode operation map (step S5).

[0095] For example, when the wiping device B is operating in the heavy rain mode, the control map is switched from the heavy rain mode operation map to the normal mode operation map in step S5. Then, by switching the control map from the heavy rain mode operation map to the normal mode operation map, the pair of CPUs 15d, 15p sets the control mode to the normal mode (step S6).

[0096] That is, when the process of step S6 is completed, the pair of CPUs 15d, 15p perform a process of generating a drive command based on the normal mode operation map. Therefore, the pair of wiper blades 1d, 1p normally wipes away rainwater by reciprocating in the driver's seat normal wiping range Rd, Rp from the lower reversal position PLd, PLp to the upper reversal position PUd, PUp.

[0097] If the determination in step S2 is "Yes", that is, if the heavy rain mode is instructed by the upper control device, the pair of CPUs 15d, 15p refer to the wiping count value N to determine whether the wiping in the heavy rain mode is the first wiping (initial wiping) (step S7).

[0098] If the determination in step S7 is "No," that is, if the wiping in the heavy rain mode is not the initial wiping, the pair of CPUs 15d, 15p terminates the process. On the other hand, if the determination in step S7 is "Yes," that is, if the wiping in the heavy rain mode is the initial wiping, the pair of CPUs 15d, 15p refer to the angle signal to determine whether the operating angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, Pup (step S8).

[0099] If the determination in step S8 is "No," that is, if the operation angles of the pair of wiper blades 1d, 1p have not reached the upper reversal positions PUd, PUp, the pair of CPUs 15d, 15p terminate the process. On the other hand, if the determination in step S8 is "Yes," that is, if the operation angles of the pair of wiper blades 1d, 1p have reached the upper reversal positions PUd, PUp, the pair of CPUs 15d, 15p switch the control map used for generating the drive command to the heavy rain mode operation map (step S9).

[0100] For example, when the wiping device B is operating in the normal mode, the control map is switched from the normal mode operation map to the heavy rain mode operation map in step S9. Then, by switching the control map from the normal mode operation map to the heavy rain mode operation map, the pair of CPUs 15d, 16p sets the control mode to the heavy rain mode (step S10).

[0101] That is, when the process of step S10 is completed, the pair of CPUs 15d, 15p perform a process of generating a drive command based on the operation map for the heavy rain mode. Therefore, the pair of wiper blades 1d, 1p reciprocate faster than in the normal mode in a narrow wiping range in which the upper reversal positions PUd, PUp are the same as the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp, but the lower reversal positions are set to lower reversal positions QLd, QLp that are higher than the lower reversal positions PLd, PLp of the driver's seat normal wiping range Rd and the passenger seat normal wiping range Rp, thereby wiping rainwater faster.

[0102] Such a wiping device B is a device that wipes rainwater off a wiped surface W by reciprocating a pair of wiper blades 1d, 1p using a pair of motors 4d, 4p (power sources), and is equipped with a pair of drive circuits 16d, 16p that drive the pair of motors 4d, 4p (power sources), and a pair of wiper drive control units 10d, 10p (control units) that respectively control the pair of drive circuits 16d, 16p, and the pair of wiper drive control units 10d, 10p (control units) switch the wiping range at a timing when the target speeds before and after the switching are both zero.

[0103] According to this second embodiment, the control map (operation mode) is switched, i.e., the wiping range is switched, at a timing when the target speed is zero both before and after the switch, so it is possible to provide a wiping device B that can suppress abnormal behavior of a pair of wiper blades 1d, 1p when the control map (operation mode) is switched, i.e., when the wiping range is switched.

[0104] In addition, according to the second embodiment, the wiping range of a pair of wiper blades 1d, 1p is set to a normal wiping range in normal mode and a wiping range in heavy rain mode that is narrower than the normal wiping range, so that abnormal behavior of the pair of wiper blades 1d, 1p can be suppressed when switching between the normal mode and the heavy rain mode.

[0105] In addition, according to the second embodiment, a pair of wiper drive control units 10d, 10p switch between normal mode and heavy rain mode at the upper reversal positions PUd, PUp, where the target speeds are both zero before and after the switch, so that abnormal behavior of the pair of wiper blades 1d, 1p when switching between normal mode and heavy rain mode can be effectively suppressed.

[0106] Furthermore, in the second embodiment, a pair of motors 4d, 4p (power sources) are provided, and of the pair of wiper blades 1d, 1p, the motor 4d on the driver's side reciprocates the wiper blade 1d on the driver's side, and the motor 4p on the passenger's side reciprocates the wiper blade 1p on the passenger's side.

[0107] That is, in the second embodiment, in a dual-motor drive wiping device B in which a pair of motors 4d, 4p (power sources) reciprocate the corresponding wiper blades, it is possible to suppress abnormal behavior of a pair of wiper blades 1d, 1p.

[0108] [Additional matters] In the second embodiment, while the driver's side wiper blade 1d wipes the driver's side narrow wiping range NRd in the heavy rain mode, the pair of wiper drive controllers 10d, 10p can stop (standby) the passenger side wiper blade 1p at the passenger side lower reversal position PLp so as not to interfere with the driver's side wiper blade 1d. In addition, in the second embodiment, the passenger side wiper blade 1p can also be stopped (standby) at the passenger side upper reversal position PUp, and the passenger side wiper blade 1p can also be made to wipe in the passenger side narrow wiping range.

[0109] In addition, in the first and second embodiments, the upper reversal positions PUd, PUP in the wiping ranges Rd, Rp in normal mode and the narrow wiping range in heavy rain mode are reversed at the same positions even when switching to each mode, but it is also possible to switch from the upper reversal positions PUd, PUP in normal mode to the upper reversal positions in heavy rain mode each time switching to each mode.

[0110] In this case, wiping can be performed in a narrow wiping range between each upper inversion position and each lower inversion position in the heavy rain mode. Also, as shown in Figure 3, control can be switched to wiping in a narrow wiping range at each upper inversion position.

[0111] Furthermore, the wiping devices A and B according to each of the above embodiments are devices that wipe rainwater off the wiped surface W by reciprocating a pair of wiper blades 1d and 1p using each of the motors 4, 4d, and 4p (power sources), and it is conceivable to use a brushless motor as each of the motors 4, 4d, and 4p (power sources).

[0112] As is well known, a brushless motor is a motor (power source) with excellent speed controllability. By adopting a brushless motor as the drive source for the pair of wiper blades 1d, 1p, when each motor 4, 4d, 4p (brushless wiper motor) rotates repeatedly in forward and reverse directions at high speed in heavy rain mode operation, wear powder from the brushes caused by sliding between the brushes and the commutator, as occurs in a brushed motor, is not generated, and it is possible to extend the life of each motor 4, 4d, 4p.

[0113] In addition, by using brushless wiper motors for each of the motors 4, 4d, and 4p, it is possible to smoothly repeat forward and reverse rotation, thereby enabling precise reversal at the upper reversal position and the lower reversal position set for the heavy rain mode. [Explanation of symbols]

[0114] A, B... wiping device, W... wiped surface, PUd, PUp... upper inverted position, PLd, PLp... lower inverted position, Rd, Rp... wiping range, Td, Tp... wiper shaft, 1d, 1p... wiper blade, 2d, 2p... wiper arm, 3... link mechanism, 4, 4d, 4p... motor (power source), 5... angle detection circuit, 6... control unit, 61... ROM, 62... RAM, 63... CPU, 7... drive circuit, 8d, 8p... motor body, 9d, 9p... reduction mechanism, 10... drive control device, 10d, 10p... wiper drive control unit, 11d, 11p... angle detection circuit, 12d, 12p... ROM, 13d, 13p... RAM, 14d, 14p... communication circuit, 15d, 15p... CPU, 16d, 16p... drive circuit

Claims

1. A wiping device that wipes rainwater off a surface to be wiped by reciprocating a wiper blade using a predetermined power source, A drive circuit that drives the power source; A control unit that controls the drive circuit, The wiping device according to claim 1, wherein the control unit switches the wiping range at a timing when both the target speeds before and after the switching are zero.

2. 2. The wiping device according to claim 1, wherein the wiping range comprises a normal wiping range in a normal mode and a narrow wiping range in a heavy rain mode which is narrower than the normal wiping range.

3. The wiping device according to claim 2 , wherein the control unit performs the switching from the normal mode to the heavy rain mode when the wiper blade is in an upper inverted position.

4. 3. The wiping device according to claim 1, wherein the power source is a brushless motor.

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