WINDSHIELD WIPER CONTROL APPARATUS

• US 3,649,898 A
• Filed: 08/19/1969
• Issued: 03/14/1972
• Est. Priority Date: 09/21/1968
• Status: Expired due to Term

• Current Assignee: Goro Inoue
• Original Assignee: Goro Inoue
• Inventors: Inoue, Goro
• Primary Examiner(s): Dobeck, Benjamin
• Application Number:
  US04/851,311
• Time in Patent Office: 938 Days
• Field of Search: 318/483,443 15/250.02,250.12
• US Class Current: 318/483
• CPC Class Codes: B60S 1/0818 including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like
• CPC Class Codes: B60S 1/0822 characterized by the arrangement or type of detection means
• CPC Class Codes: B60S 1/0851 Resistive rain sensor
• CPC Class Codes: Y10S 15/15 Moisture responsive

Abstract

An apparatus for automatically controlling the starting and stopping of a windshield wiper, the shifting of the wiper operation from a low speed operation to a high speed operation or vice versa, and the stopping of the wiper in a fixed resting position, which comprises a water drop detector having at least two electrodes mounted on the outer surface of the windshield with a small space interval therebetween, a control circuit for controlling the starting time or stopping time of the wiper operation in response to a signal obtained synchronously with the energization of said water drop detector caused by a drop of water attached thereto or a reciprocatory movement of the wiper blade, and a relay and an amplifier for actuating said relay.

Claims

1. An apparatus for controlling a windshield wiper and its drive motor connected in a power source circuit, comprising a water drop detector having at least two electrodes adapted to be mounted on the outer surface of a windshield with a small space interval therebetween, an amplifier electrically connected to said water drop detector which operates said amplifier upon energization of said water drop detector, said amplifier being provided with a retaining mechanism including time-limiting means for establishing a predetermined time period, and a switch device operated by said amplifier to close said power source circuit of said wiper-driving motor upon said energization of the water drop detector and also to actuate said retaining mechanism so that when said water drop detector has been returned to the deenergized state the amplifier is enabled by said time-limiting means to continue its operation of retaining said power circuit closed by said switch device for only said predetermined time period as established by said time-limiting means, wherein said water drop detector comprises a rotary disc and two conductor plates arranged on said rotary disc in electrically insulated relation to each other with a slight space interval therebetween, said rotary disc being mounted on the drive shaft of another motor which is started and stopped by said switch device concurrently with said wiper driving motor.

2. An apparatus for controlling a windshield wiper and its drive motor connected in a power source circuit, comprising a water drop detector having at least two electrodes adapted to be mounted on the outer surface of a windshield with a small space interval therebetween, an amplifier electrically connected to said water drop detector which operates said amplifier upon energization of said water drop detector, said amplifier being provided with a retaining mechanism including time-limiting means for establishing a predetermined time period, and a switch device operated by said amplifier to close said power source circuit of said wiper-driving motor upon said energization of the water drop detector and also to actuate said retaining mechanism so that when said water drop detector has been returned to the deenergized state the amplifier is enabled by said time-limiting means to continue its operation of retaining said power circuit closed by said switch device for only said predetermined time period as established by said time-limiting means, wherein said water drop detector has three or more electrodes mounted on the outer surface of a windshield at two different space intervals between each other so as to define a narrow space or spaces and a slightly wider space or spaces, and said amplifier includes a first amplifier for actuating the switch device upon energization of those electrodes of said water drop detector which define the narrow space and a second amplifier for actuating the switch device upon energization of those electrodes of said water drop detector which define the wider space, said switch device being actuated by said first amplifier serving to open and close the power source circuit of the wiper-driving motor and also to actuate said retaining mechanism when said electrodes defining the narrow space have been returned to the deenergized state so as force said first amplifier to continue its operation, said switch device being actuated by said second amplifier serving to shift said wiper-driving motor from a low speed circuit to a high speed circuit or vice versa.

3. An apparatus for automatically controlling a windshield wiper, comprising a water drop detector adapted to be energized upon detecting a drop of water, a switch adapted to be opened and closed in synchronized relation to a reciprocatory movement of a wiper blade which is connected to a wiper arm and driven frOm a wiper-arm-driving motor through a link mechanism, a differentiation circuit electrically connected to said switch for producing a trigger pulse upon receipt of a signal from said switch, a monostable multivibrator operating in response to said trigger pulse, and an amplifier and a switch device electrically connected to said water drop detector to be actuated thereby upon energization of the latter, the input voltage of said water drop detector being dropped to zero only immediately after said wiper blade has been set in its fixed position of rest by the output of said monostable multivibrator, and said wiper-arm-driving motor being driven through said amplifier and said switch device upon energization of said water drop detector and maintained in operation through said switch and said relay until said water drop detector is deenergized and immediately before said wiper blade reaches its fixed position of rest.

4. An apparatus for controlling a windshield wiper and its drive motor connected in a power source circuit, comprising a water drop detector having at least two electrodes adapted to be mounted on the outer surface of a windshield with a small space interval therebetween, an amplifier electrically connected to said water drop detector which operates said amplifier upon energization of said water drop detector, said amplifier being provided with a retaining mechanism including time-limiting means for establishing a predetermined time period, and a switch device operated by said amplifier to close said power source circuit of said wiper-driving motor upon said energization of the water drop detector and also to actuate said retaining mechanism so that when said water drop detector has been returned to the deenergized state the amplifier is enabled by said time-limiting means to continue its operation of retaining said power circuit closed by said switch device for only said predetermined time period as established by said time-limiting means, wherein said time-limiting means includes an resistance capacitance circuit and means to cause charging of said capacitance upon the said energization of said detector and discharging thereof up deenergization of said detector, said discharging being effective to keep said amplifier operative for said predetermined time period.

5. Apparatus as in claim 4 in combination with said drive motor and connected power source circuit.

6. Apparatus for automatically controlling a drive motor connected in a power source circuit for driving a window wiper for a windshield or the like in response to water shorting at least two spaced electrodes of a water drop detector, comprising:

an amplifier having means for connection to said detector for causing amplifier operation during the shorting of said electrodes, timing means operated by said amplifier for automatically keeping said amplifier operating for a predetermined time period after said electrodes become unshorted, and switch means operated by said amplifier for closing said power source circuit to said drive motor only while said amplifier is operating, wherein said amplifier includes at least one transistor having input bias and output circuits, said timing means including resistance and capacitance connected between said input and output circuits and having means for changing the charge on said condenser in one direction during operation of said amplifier for supplying bias to said transistor for said time period upon cessation of the shorting of said electrodes.

7. Apparatus for automatically controlling a drive motor connected in a power source circuit for driving a window wiper for a windshield or the like in response to water shorting at least two spaced electrodes of a water drop detector, comprising:

an amplifier having means for connection to said detector for causing amplifier operation during the shorting of said electrodes, timing means operated by said amplifier for automatically keeping said amplifier opeRating for a predetermined time period after said electrodes become unshorted, and switch means operated by said amplifier for closing said power source circuit to said drive motor only while said amplifier is operating, said apparatus being for use with a water drop detector which has at least a third electrode spaced from an adjacent one of said two electrodes a different interval than the interval between said two electrodes and for use with a said drive motor of the type having at least two speeds, wherein said apparatus further includes, a second amplifier having means for connection to said third and adjacent electrodes for operating said second amplifier when said third and adjacent electrodes are shorted, and means for switching said drive motor from one of said two speeds to the other only while said second amplifier is operated as aforesaid.

8. Apparatus for automatically controlling a drive motor connected in a power source circuit for driving a window wiper for a windshield or the like in response to water shorting at least two spaced electrodes of a water drop detector, comprising:

an amplifier having means for connection to said detector for causing amplifier operation during the shorting of said electrodes, timing means operated by said amplifier for automatically keeping said amplifier operating for a predetermined time period after said electrodes become unshorted, and switch means operated by said amplifier for closing said power source circuit to said drive motor only while said amplifier is operating, said apparatus further including a three position manual switch having an on position, automatic position, and off position, means for connecting said switch in its on position to said power source circuit and amplifier to operate said switch means and motor non-automatically regardless of the presence or absence of water shorting said electrodes, said switch in its automatic position being disconnected from said power source to permit the aforesaid automatic operation of said amplifier, and means connected to said switch and operative upon movement of said switch to said off position for turning off said amplifier and open said power source circuit immediately even if said time period has yet not expired.

9. Apparatus for automatically controlling a drive motor to effect reciprocation from and to a fixed position of rest of a window wiper blade for a windshield or the like in response to water shorting at least two spaced electrodes of a water drop detector, comprising:

means including a two position switch for producing a trigger pulse while said switch is in one of said positions only during each time said blade approaches said rest position, a monostable multivibrator having an output and stable and unstable states for respectively producing at said output off and on output signals and being responsive to said trigger pulse to change to said unstable state for a first predetermined period of time to produce said off output signal following which it automatically reverts to said stable state to produce said on output signal for a second time period which ends upon receipt of the next trigger pulse, actuable switch means having an input and being connected to said switch for operating said drive motor while said switch means is turned on and also while it is turned off if said switch is then in the other of said two positions, and means for connecting said electrodes respectively to said multivibrator output and said actuable switch means input for applying said multivibrator on and off output signals to said switch means to turn the same on and off only while said electrodes are shorted.

10. Apparatus as in claim 9 wherein said second time period has a duration of from about one-third to about two-thirds of the sum of the durations of said first and second time periods.