Control apparatus for windshield wiper system
First Claim
1. In a window wiper system having a wiper for wiping a window and a control system for driving said wiper intermittently through wipe cycles with dwell periods at the ends of said wipe cycles, the improvement comprising a pump motor adapted when energized to apply fluid to said window, washer control means to energize said pump motor when actuated, said control system including means to drive said wiper through a plurality of wipe cycles without a dwell period between wipe cycles in response to actuation of said washer control means, said control system including a capacitance and a resistor connected to said capacitance during said dwell period to change the charge on said capacitance during said dwell period and first circuit means responsive to the potential on one side of said capacitance to initiate a wipe cycle at the end of each dwell period and to initiate dwell periods at the end of wipe cycles, and second circuit means responsive to actuation of said washer control means to change the charge on said capacitance so that said first circuit means will not initiate a dwell period at the end of at least the first wipe cycle following actuation of said washer control.
0 Assignments
0 Petitions
Accused Products
Abstract
Control apparatus for an electric windshield wiper motor to permit a plurality of desirable windshield wiper system features to be realized including continuous and intermittent wiping operation with variable dwell, and coordinated manual or automatic wash and wipe operation. Some of the circuits implementing the control apparatus include a Zener diode and require only a single capacitor.
41 Citations
16 Claims
- 1. In a window wiper system having a wiper for wiping a window and a control system for driving said wiper intermittently through wipe cycles with dwell periods at the ends of said wipe cycles, the improvement comprising a pump motor adapted when energized to apply fluid to said window, washer control means to energize said pump motor when actuated, said control system including means to drive said wiper through a plurality of wipe cycles without a dwell period between wipe cycles in response to actuation of said washer control means, said control system including a capacitance and a resistor connected to said capacitance during said dwell period to change the charge on said capacitance during said dwell period and first circuit means responsive to the potential on one side of said capacitance to initiate a wipe cycle at the end of each dwell period and to initiate dwell periods at the end of wipe cycles, and second circuit means responsive to actuation of said washer control means to change the charge on said capacitance so that said first circuit means will not initiate a dwell period at the end of at least the first wipe cycle following actuation of said washer control.
-
8. In a windshield wiper system having a wiper for wiping a window of an automotive vehicle, having an ignition the improvement of a control system energized whenever the ignition of said automotive vehicle is turned on driving said wiper intermittently through wipe cycles with dwell periods at the ends of said wipe cycles, a pump motor adapted when energized to apply fluid to said window, washer control means to energize said pump motor when actuated, said control system including means to drive said wiper through at least one wipe cycle in response to the actuation of said washer control means, and means to vary the length of said dwell period at the end of each wipe cycle depending upon the amount of moisture on said windshield during said wipe cycle.
-
9. Apparatus for controlling the operation of a window wiper system having a wiper, a wiper motor and a single pole, double throw switch associated therewith, the switching state of said switch being determined by the position of the wiper comprising:
-
a capacitor, the first terminal of which is adapted to be operably connected to the pole terminal of the switch; a switching transistor connected in circuit with said wiper motor so that the on or off switching state of said transistor controlled by its base current is adapted to control the operating state of the wiper motor; a first diode and a first resistor connected in a parallel circuit between the second terminal of said capacitor and the base of said switching transistor; and a second resistor, and circuit means operable to connect said second resistor between a source of power and the side of said parallel circuit connected to the base of said switching transistor. - View Dependent Claims (10, 12, 13)
-
-
11. Apparatus according to claim 11, further comprising a third resistor, the first terminal of which is connected to the second terminal of said Zener diode.
- 14. In a window wiper system having a wiper for wiping a window and a control system for driving said wiper intermittently through wipe cycles with dwell periods at the ends of said wipe cycles, the length of said dwell period depending upon the degree of dryness of said windshield being longer for dry windshields and shorter for wet windshields, the improvement wherein the window wiper system includes means to energize said wiper motor with a reduced voltage at the end of each wipe cycle, and means to control the length of said dwell period by the distance that the wiper blades move at the end of a wipe cycle after said motor is energized with reduced voltage.
-
16. In a window wiper system for an automotive vehicle having an ignition switch, said wiper system having a wiper for wiping a window and a control system operable to operate said wiper in an intermittent mode, driving said wiper through wipe cycles with dwell periods at the ends of said wipe cycles, the length of the dwell period provided at the end of each wipe cycle depending upon the degree of dryness of the windshield, there being a longer dwell period for relatively dry windshields and a shorter dwell period for wet windshields, the improvement wherein said control system includes means to automatically operate said wiper in said intermittent mode whenever the ignition switch of said automotive vehicle is turned on.
Specification