Moisture-sensing window cleaning control system

Claim 2

A automatic control system for operating an electrically actuated device in response to the presence of water moisture, said control system comprising, in combination: a moisture sensor having a plurality of spaced-apart, exposed conductive sensor elements, said elements being arranged as in a plurality of adjacent pairs; a voltage source; current detection means, having an input and an output, for indicating, by a signal at said output, when the current flow at said input exceeds a prescribed threshold; first connection means for connecting said voltage source to a first element of each of said plurality of adjacent pairs; second connection means for connecting said input of said current detector means to a second element of each of said plurality of adjacent pairs; means for incrementing said first and second connection means in synchronism, such that said voltage source is connected to said first element when said current detection means is connected to said second element of the same pair; and means for adapting said output signal of said current detection means to control the operation of said electrically actuated device.

Claim 3

The control system defined in claim 1, wherein said means for incrementing acts to alternately increment said first and second connection means.

Claim 4

The control system defined in claim 2, wherein said means for incrementing includes clock generator means for producing a square-wave signal and is adapted to increment said first connection means in response to the leading edge of a square-wave signal and to increment said second connection means in response to the trailing edge of a square-wave signal.

Claim 5

The control system defined in claim 2 wherein said adjacent pairs of elements are arranged successively on a substrate, and said connection means are incremented to connect said voltage source and said current detection means to successive pairs of said elements.

Claim 6

The control system defined in claim 1 further comprising a resistor connected between at least one element of each adjacent pair and ground.

Claim 7

The automatic control system defined in claim 1 wherein said means for adapting comprises integration means for accumulating said output signal of said current detection means to provide a control signal for said electronic actuated device.

Claim 8

The automatic control system defined in claim 1 wherein said first and second connection means each include a multiplexer connected to said plurality of sensor elements.

Claim 9

The automatic control system defined in claim 1 wherein said current detection means comprises a plurality of inputs connected to said plurality of sensor elements and summing means for determining the total number of adjacent sensor element pairs for which the current flow exceeds said prescribed threshold.

Claim 10

Apparatus for wiping a window in response to the presence of water moisture thereon, said apparatus comprising, in combination: electrically actuated window wiper means having a wiper blade arranged to move in strokes to and fro across said window between two end positions to wipe moisture from a prescribed area on said window between said two end positions, said wiper means including open ignition park switch means for maintaining the operation of said wiper means, once actuated, until said wiper blade reaches a park position; a moisture sensor, having a first electrical output, for sensing the presence of moisture on said window; wiper position sensor means, having a second bounce-free electrical output, for determining the position of said wiper blade between said two end positions; and control means, having first and second inputs connected to said first and second electrical outputs, respectively, and a third electrical output connected to said wiper means, for actuating said wiper means when said moisture sensor indicates the presence of excessive moisture, said control means including means responsive to said position sensor means for maintaining the operation of said wiper means until said wiper blade is next positioned in said park position, thereby to cause said wiper blade to complete each stroke initiated.

Claim 11

Apparatus for wiping a window in response to the presence of water moisture thereon, said apparatus comprising, in combination: electrically actuated window wiper means having a wiper blade arranged to move in strokes to and fro across said window between two end positions to wipe moisture from a prescribed area on said window between said two end positions, said wiper means including open ignition park switch means for maintaining the operation of said wiper means, once actuated, until said wiper blade reaches a park position; a moisture sensor, having a first electrical output, for sensing the presence of moisture on said window; wiper position sensor means, having a second bounce-free electrical output, for determining the position of said wiper blade between said two end positions; and control means, having first and second inputs connected to said first and second electrical outputs, respectively, and a third electrical output connected to said wiper means, for actuating said wiper means when said moisture sensor indicates the presence of excessive moisture, said control means including means responsive to said position sensor means for maintaining the operation of said wiper means until said wiper blade is next positioned in said park position, thereby to cause said wiper blade to complete each stroke initiated.

Claim 12

The apparatus defined in claim 9 wherein said wiper position sensor means comprises at least one Hall-effect device and at least one magnet.

Claim 13

The apparatus defined in claim 10 wherein said wiper means comprises mechanical linkage means for mechanically actuating said wiper blade and wherein said magnet is arranged on said mechanical linkage.

Claim 14

The apparatus defined in claim 9 wherein said position sensor means produces a signal indicative of the position of said wiper blade along substantially its entire stroke.

Claim 15

The apparatus defined in claim 12, wherein said position sensor means comprises at least one analog Hall-effect device for producing an analog signal representing the position of said wiper blade along its stroke.

Claim 16

The apparatus defined n claim 9, wherein said position sensor means produces a signal indicative of presence of said wiper blade at one particular position along its stroke.

Claim 17

The apparatus defined in claim 9 wherein said park switch means includes keep-alive means for maintaining said operation during ignition shutdown until said wiper blade reaches said park position.

Claim 18

Apparatus for wiping a window in response to the presence of water moisture thereon, said apparatus comprising, in combination: electrically actuated window wiper means having a wiper blade arranged to move in strokes to and fro across said window to wipe moisture from a prescribed area, said wiper means including park switch means for maintaining the operation of said wiper means, once actuated, until said wiper blade reaches a park position; a moisture sensor arranged on said window within said prescribed area in the path of said wiper blade for sensing the presence of moisture on said window, said moisture sensor having a first electrical output; wiper position sensor means, having a second electrical output, for determining when said wiper blade is positioned over said moisture sensor; and control means, having first and second inputs connected to said first and second electrical outputs, respectively, and a third electrical output connected to said wiper means, for producing a wiper actuating signal at said third output when said moisture sensor indicates the presence of excessive moisture, said control means including means responsive to said position sensor means for inhibiting said wiper actuating signal when said wiper blade is positioned over said moisture sensor, thereby to prevent reactuation of said wiper means due to the presence of moisture carried by the wiper blade over said moisture sensor.

Claim 19

Apparatus for wiping a window in response to the presence of water moisture thereon, said apparatus comprising, in combination: electrically actuated window wiper means having a wiper blade arranged to move in strokes to and fro across said window to wipe moisture from a prescribed area, said wiper means including park switch means for maintaining the operation of said wiper means, once actuated, until said wiper blade reaches a park position; a moisture sensor arranged on said window within said prescribed area in the path of said wiper blade for sensing the presence of moisture on said window, said moisture sensor having a first electrical output; wiper position sensor means, having a second electrical output, for determining when said wiper blade is positioned over said moisture sensor; and control means, having first and second inputs connected to said first and second electrical outputs, respectively, and a third electrical output connected to said wiper means, for producing a wiper actuating signal at said third output when said moisture sensor indicates the presence of excessive moisture, said control means including means responsive to said position sensor means for inhibiting said wiper actuating signal when said wiper blade is positioned over said moisture sensor, thereby to prevent reactuation of said wiper means due to the presence of moisture carried by the wiper blade over said moisture sensor.

Claim 20

The apparatus defined in claim 16 wherein said position sensor means comprises at least two Hall-effect devices and magnets, one of said Hall-effect devices and said magnets being arranged to move in synchronism with said wiper blade and another of said Hall-effect devices and said magnets being stationary with respect to said wiper blade.

Claim 21

The apparatus defined in claim 17 wherein said wiper means includes mechanical linkage means for mechanically actuating said wiper blade and wherein one of said magnets is arranged on said mechanical linkage.

Claim 22

Window wiper apparatus comprising, in combination: electrically actuated window wiper means having a wiper blade arranged to move in strokes to and fro across said window to wipe moisture from a prescribed area on said window, said wiper means including open ignition park switch means for maintaining the operation of said wiper means, once actuated, until said blade reaches a park position; wiper position sensor means, having a first bounce-free electrical output, for determining when said wiper blade has moved away from said park position; and control means, having an input connected to said first electrical output and a second electrical output connected to said window wiper means, for producing a signal at said second output to control the operation of said wiper means, said control means including means responsive to said position sensor means for interrupting the operation of said wiper means if said wiper blade remains in said park position for a prescribed time after initiating operation of said wiper means, thereby to prevent damage to said wiper means when said wiper blade is frozen in position for any reason.

Claim 23

Window wiper apparatus comprising, in combination: electrically actuated window wiper means having a wiper blade arranged to move in strokes to and fro across said window to wipe moisture from a prescribed area on said window, said wiper means including open ignition park switch means for maintaining the operation of said wiper means, once actuated, until said blade reaches a park position; wiper position sensor means, having a first bounce-free electrical output, for determining when said wiper blade has moved away from said park position; and control means, having an input connected to said first electrical output and a second electrical output connected to said window wiper means, for producing a signal at said second output to control the operation of said wiper means, said control means including means responsive to said position sensor means for interrupting the operation of said wiper means if said wiper blade remains in said park position for a prescribed time after initiating operation of said wiper means, thereby to prevent damage to said wiper means when said wiper blade is frozen in position for any reason.

Claim 24

The apparatus defined in claim 19 wherein said control means further comprises means for producing an audible alarm when said wiper means operation is interrupted.

Claim 25

A automatic control system for operating an electrically actuated window wiper device in response to the presence of water moisture on a window, said window wiper device including a wiper blade and means for moving said wiper blade in strokes to and fro across the window to wipe the window clean in a prescribed area, and for operating a window washer device in response to the presence of impure moisture on the window, said control system comprising, in combination: a moisture sensor arranged on the window within the prescribed area and having a plurality of spaced-apart, exposed conductive sensor elements forming at least one adjacent pair of elements; a voltage source; current detection means, having at least one input and at least one output, for indicating, by a signal at said output, when the current flow at said input exceeds a first prescribed threshold and when it exceeds a second prescribed threshold which is higher than said first prescribed threshold; first means for connecting said voltage source to at least a first one of said sensor elements; second means for connecting said input of said current detection means to at least a second one of said sensor elements, said first and second ones of said sensor elements to which said voltage source and said current detection means are simultaneously connected belonging both to the same pair of adjacent elements; and control means, coupled to current detection means, for enabling said window wiper device to be switched on when the current received from at least one pair of adjacent sensor elements exceeds said first prescribed threshold, and for enabling said window washer device to be switched on when the current received from at least one pair of adjacent sensor elements exceeds said second prescribed threshold.

Claim 26

A automatic control system for operating an electrically actuated window wiper device in response to the presence of water moisture on a window, said window wiper device including a wiper blade and means for moving said wiper blade in strokes to and fro across the window to wipe the window clean in a prescribed area, and for operating a window washer device in response to the presence of impure moisture on the window, said control system comprising, in combination: a moisture sensor arranged on the window within the prescribed area and having a plurality of spaced-apart, exposed conductive sensor elements forming at least one adjacent pair of elements; a voltage source; current detection means, having at least one input and at least one output, for indicating, by a signal at said output, when the current flow at said input exceeds a first prescribed threshold and when it exceeds a second prescribed threshold which is higher than said first prescribed threshold; first means for connecting said voltage source to at least a first one of said sensor elements; second means for connecting said input of said current detection means to at least a second one of said sensor elements, said first and second ones of said sensor elements to which said voltage source and said current detection means are simultaneously connected belonging both to the same pair of adjacent elements; and control means, coupled to current detection means, for enabling said window wiper device to be switched on when the current received from at least one pair of adjacent sensor elements exceeds said first prescribed threshold, and for enabling said window washer device to be switched on when the current received from at least one pair of adjacent sensor elements exceeds said second prescribed threshold.

Claim 27

The apparatus defined in claim 21 wherein said moisture sensor includes a plurality of adjacent pairs of sensor elements and wherein said control means includes means for enabling said window wiper device to be switched on when the number of said pairs of sensor elements, for which the current flow through each respective pair exceeds said first prescribed threshold, exceeds a third prescribed threshold.

Claim 28

The apparatus defined in claim 22, wherein said control means includes: latch means having a set input, coupled to said output of said current detection means, a reset input and a first output indicative of the state of said latch means, said latch means being set when said current flow at said input of said current detection means exceeds said second prescribed threshold; counter means having a counter input, an enable input coupled to said first output of said latch means and an output indicative of the count in said counter means; and means for producing at least one pulse during each complete stroke of said wiper blade, said pulse being applied to said reset input of said latch means and said counter input of said counter means, wherein said window washer device is switched on when the count in said counter means is at least equal to a fourth prescribed threshold.

Claim 29

The apparatus defined in claim 23 further comprising means for resetting said counter means and separate means for activating said window wiper device when said window washer device is activated.

Claim 30

The apparatus defined in claim 22 wherein said control means includes: latch means coupled to said current detection means for indicating, when in one state, the presence of impurities on said window and indicating, when in another state, the absence of impurities on said window, said latch means having a first output indicative of the state of said latch means; up-down counter means having a count input, a counter control input coupled to said first output of said latch means and an output indicative of the count in said counter means; and means for producing at least one pulse during each complete stroke of said wiper blade, said pulse being applied to said count input of said counter means, wherein said counter means counts in one direction when impurities are present and in the opposite direction when impurities are not present on said window, and wherein said window washer device is switched on when the count in said counter means is at least equal to a fourth prescribed threshold.

Claim 31

The apparatus defined in claim 21 wherein said control means includes means for activating said window washer device on when the current flowing through at least one pair of said sensor elements continues to exceed said second prescribed threshold after said wiper blade passes over said moisture sensor.

Claim 32

The apparatus defined in claim 26, wherein said control means includes means for activating said window washer device when the current flowing through at least one pair of said sensor elements continues to exceed said second prescribed threshold after said wiper blade passes over said moisture sensor a number of times which exceeds a fourth prescribed threshold.

Claim 33

The apparatus defined in claim 21 further comprising sensitivity display means for displaying said second prescribed threshold.

Claim 34

The apparatus defined in claim 21 further comprising moisture display means for displaying the number of said adjacent moisture sensor pairs for which said current received exceeds said first prescribed threshold.