Patent US3604997A successfully refreshed from Google Patents.
US3604997A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for the driving motor of windshield wipers
Assignee: Individual
•
Filing: 1969-04-15
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Granted: 1971-09-14
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Expires: 1989-04-15
Abstract
Abstract An intermittent windshield wiper system having a first switch actuated by a voltage drop responsive to the motor load, timing means comprising an unstable multivibrator actuated by the first switch means and controlling second switch means in series with the motor and a power source.
Inventors
- 👤 Karl Kirchner
- 👤 Ernst Kirchner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:28
CPC Classifications
B; B60; B60S; B60S1/00; B60S1/02; B60S1/04; B60S1/06; B60S1/08; B60S1/46; B60S1/48; B60S1/481; B60S1/482
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
119 words
A system for wiping the windshield of an automobile, comprising: a wiper, a main electric circuit including a direct current source and a motor operatively connected to said wiper for driving said wiper, a resistance for producing a voltage drop when the current consumption of said motor increased due to increased frictional resistance of the windshield to movement of said wiper, first switch means connected to said resistance and actuated by said voltage drop, second switch means in series with said motor, timing or time-delay means actuated by said first switch means for controlling said second switch means, said timing or time-delay means including an unstable multivibrator having a switch relay associated therewith and actuating said second switch means.
Claim 2
Independent Claim
119 words
A system for wiping the windshield of an automobile, comprising: a wiper, a main electric circuit including a direct current source and a motor operatively connected to said wiper for driving said wiper, a resistance for producing a voltage drop when the current consumption of said motor increased due to increased frictional resistance of the windshield to movement of said wiper, first switch means connected to said resistance and actuated by said voltage drop, second switch means in series with said motor, timing or time-delay means actuated by said first switch means for controlling said second switch means, said timing or time-delay means including an unstable multivibrator having a switch relay associated therewith and actuating said second switch means.
Claim 3
Dependent Claim
12 words
A system as defined in claim 1 wherein said resistance is adjustable.
Claim 4
Dependent Claim
47 words
A system as defined in claim 2, said main circuit comprising a main switch connected in series with said second switch means and park switch means connecting the arm of said adjustable resistance to said motor for varying the speed of said motor by said adjustable resistance.
Claim 5
Dependent Claim
24 words
A system according to claim 1 wherein said timing or time delay means further comprises a low-frequency generator coupled to said first switch means.
Claim 6
Dependent Claim
58 words
A system as defined in claim 1 wherein said first switch means is in the form of a transistor having a base connected to said resistance, an emitter connected to one pole of said source in said main circuit, and a collector connected to the opposite pole of said source and coupled to said timing or time-delay means.
Claim 7
Dependent Claim
54 words
A system according to claim 5 wherein said timing or time-delay means comprises a reaction coil, a condenser connected between said reaction coil and said base, a primary coil series connected to said collector, a secondary coil coupled to a rectifier, and timing condenser-resistor circuit means connected between said rectifier and said unstable multivibrator.
Claim 8
Dependent Claim
33 words
A system as defined in claim 1, said main circuit further comprising a throwover switch bridging said second switch means and said resistance for selecting continuous and intermittent operation of said motor, respectively.
Claim 9
Dependent Claim
31 words
A system according to claim 1 wherein said timing or time-delay means further comprises a bimetalic switch connected to and influenced by said first switch means to control said unstable multivibrator.
Claim 10
Dependent Claim
36 words
A system according to claim 6 wherein at least one condenser and at least one adjustable resistance are associated with said unstable multivibrator for adjusting the impulse time according to the voltage drop in said resistance.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |