Windshield wiper system

• US 6,281,649 B1
• Filed: 06/30/1999
• Issued: 08/28/2001
• Est. Priority Date: 01/03/1997
• Status: Expired due to Fees

• Current Assignee: McCord Winn Textron Incorporated
• Original Assignee: McCord Winn Textron Incorporated
• Inventors: Ziegler, William E., Prendergast, William H., Ouellette, Thomas J.
• Primary Examiner(s): Nappi, Robert E.
• Assistant Examiner(s): Duda, Rina I.
• Application Number:
  US09/341,043
• Time in Patent Office: 790 Days
• Field of Search: 318/443, 318/444, 318/466, 318/480, 318/483, 318/DIG. 2, 15/250.001, 15/250.12, 15/250.13
• US Class Current: 318/443
• CPC Class Codes: B60S 1/0416 including other vehicle fittings
• CPC Class Codes: B60S 1/08 electrically driven conjoint control of windscreen wiper motor and liquid supply of windscreen washer B60S1/482; conjoint control of windscreen wiper motor and means for cleaning parts o parts other than windscreens or front windows B60S1/56, B60S1/58, B60S1/606
• CPC Class Codes: B60S 1/0807 using electronic control means, e.g. tubes, semiconductors B60S1/0818, B60S1/0896 take precedence
• CPC Class Codes: B60S 1/0814 using several drive motors; motor synchronisation circuits
• 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 1/0859 Other types of detection of rain, e.g. by measuring friction or rain drop impact
• CPC Class Codes: B60S 1/0866 including a temperature sensor heating devices for windshield B60H
• CPC Class Codes: B60S 1/0896 including control systems responsive to a vehicle driving condition, e.g. speed
• CPC Class Codes: B60S 1/166 characterised by the combination of a motor-reduction unit and a mechanism for converting rotary into oscillatory movement
• CPC Class Codes: B60S 1/486 including control systems responsive to a vehicle driving condition, e.g. speed
• CPC Class Codes: B60S 1/50 Arrangement of reservoir
• CPC Class Codes: H02P 29/40 Regulating or controlling the amount of current drawn or delivered by the motor for controlling the mechanical load
• CPC Class Codes: Y10S 318/02 Windshield wiper controls

Abstract

A dual motor windshield wiper system and windshield washer system integrated together into a single assembly. The system includes two motors (22, 22′), a control circuit (12), a fluid reservoir (120), a pump (112), and at least one mounting member (108, 108′) that supports said motors. The reservoir can be located between the two motors and can be supported in place by the motors. The motors can be thermally coupled to the reservoir so that fluid within the reservoir acts as a heat sink for the motors. The positions of the wipers can be controlled to follow targeted positions that are determined in accordance with acceleration, velocity, and deceleration values that are calculated using a wiper speed setting selected by the vehicle driver.

Claims

1. In a windshield wiper system for a vehicle, the wiper system having a first electric motor, a second electric motor, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said first motor and said first drive shaft are spaced from said second motor and second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, and wherein said fluid reservoir is supported at a first end by said first motor and is supported at said second end by said second motor, with said reservoir being constrained in said intervening space between said motors.

2. A windshield wiper system as defined in claim 1, wherein said fluid reservoir includes first and second spaced recesses and wherein said first and second motors have housings that extend into said first and second recesses, respectively.

4. A windshield wiper system as defined in claim 1, wherein said first and second motors are coupled to their associated drive shafts by respective first and second gear boxes, wherein said one or more mounting members comprise a first mounting member secured to said first gear box and a second mounting member secured to said second gear box.

5. A windshield wiper system as defined in claim 4, wherein said fluid reservoir extends between and is supported by said first and second motors.

3. In a windshield wiper system for a vehicle, the wiper system having a first electric motor, a second electric motor, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said first motor and said first drive shaft are spaced from said second motor and second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, and wherein said fluid reservoir is supported at a first end by said first motor and is supported at said second end by said second motor, with said reservoir being constrained in said intervening space between said motors;

wherein said fluid reservoir includes first and second spaced recesses and wherein said first and second motors have housings that extend into said first and second recesses, respectively; and

wherein said fluid reservoir comprises a molded housing and wherein said first and second recesses are defined by respective first and second sets of fingers that extend from said molded housing.

6. In a windshield wiper system for a vehicle, the wiper system having a first electric motor, a second electric motor, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said fist motor and said first drive shaft are spaced from said second motor and second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, and wherein said fluid reservoir includes first and second unitary portions that comprise housings for said first and second motors, respectively.

7. A windshield wiper system as defined in claim 6, wherein said first and second unitary portions define respective first and second recesses in an outre surface of said fluid reservoir.

8. In a windshield wiper system for a vehicle, the wiper system having a fist electric motor, a second electric motor, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said first motor and said first drive shaft are spaced from said second motor and second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, and wherein said fluid reservoir includes first and second unitary portions that comprise housings for said first and second motors, respectively; and

wherein said first and second motors each include a metal housing thermally coupled to the interior of said fluid reservoir, whereby fluid within said reservoir acts as a heat sink to thereby remove heat from said motors.

9. In a windshield wiper system for a vehicle, the wiper system having a first electric motor, a second electric motor, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said first motor and said first drive shaft are spaced from said second motor and second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, with said fluid reservoir being attached to said one or more mounting members and wherein said fluid reservoir is located in said intervening space with said motors being supported thereof.

10. In a windshield wiper system for a vehicle, the wiper system having a first electric motor, a second electric motor, a control circuit, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said first motor and said first drive shaft are spaced from said second motor and second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, wherein said fluid reservoir includes at least one thermally conductive member that is thermally coupled to the interior of said fluid reservoir, and wherein said control circuit includes one or more power devices thermally coupled to said thermally conductive member, whereby fluid within said reservoir acts as a heat sink to thereby remove heat from said one or more power devices via said thermally conductive member.

11. A windshield wiper system as defined in claim 10, wherein said fluid reservoir comprises a molded housing having a metal plate thermally coupled to the interior of said reservoir and to said one or more power devices.

12. In a windshield wiper system for a vehicle, the wiper system having a first electric motor, a second electric motor, a fluid reservoir, and a pump;

said first electric motor being operable to rotate a first drive shaft that is adapted to support a first wiper blade and said second electric motor being operable to rotate a second drive shaft that is adapted to support a second wiper blade, wherein said fist motor and said first drive shaft are spaced from said second motor an second drive shaft by an intervening space; and

said pump being coupled to said reservoir to pump windshield wiper fluid from said reservoir;

characterized in that said motors, fluid reservoir, and pump are connected together as a single assembly, wherein said assembly includes one or more mounting members that support said motors, fluid reservoir, and pump, and wherein said fluid reservoir includes a metal contact within a lower portion of the interior of said reservoir, said contact being electrically grounded whereby windshield washer fluid within said reservoir is electrically grounded to thereby reduce electromagnetic interference radiated by said motors.

13. In a windshield wiper system having a first motor, a second motor, and a control circuit having first and second outputs connected to said first and second motors, respectively, said first and second motors each including a brushless dc motor having an output shaft for providing rotation to an associated wiper blade and said first and second motors further including an encoder that provides pulses indicative of angular displacements of the encoder'"'"'s associated motor, wherein said control circuit is operable to use said pulses for commutation of said brushless dc motors, characterized in that:

said control circuit being further operable to use said pulses to determine the position of at least one of the wiper blades, with said control circuit being operable to count at least certain ones of said pulses and to determine the position of the wiper blade based upon said count.

14. A windshield wiper system as defined in claim 13, wherein said encoder utilizes Hall effect sensors to generate said pulses.

15. A windshield wiper system as defined in claim 13, wherein said first and second motors each include a drive module that provides commutation of said motors using said pulses.

16. A windshield wiper system as defined in claim 13, wherein said control circuit provides commutation of said motors using said pulses.

17. A windshield wiper system as defined in claim 13, wherein, for each of said motors, said control circuit is operable to track the position of the motor'"'"'s associated wiper blade by incrementing a counter for each pulse occurring as a result of rotation of the motor in one direction and decrementing the counter for each pulse occurring as a result of rotation of the motor in the other direction.

18. In a windshield wiper system having a first motor, a second motor, and a control circuit having first and second outputs connected to said first and second motors, respectively,

said first and second motors each including an output shaft for providing rotation to an associated wiper blade and an encoder that provides pulses indicative of angular displacements of the encoder'"'"'s associated motor,

characterized in that said control circuit being operable to measure the magnitude of current flowing through at least one of said motors and to determine a park position for the wiper blades using said measured current.

19. In a windshield wiper system having a first motor, a second motor, and a control circuit having first and second outputs connected to said fist and second motors, respectively,

said first and second motors each including an output shaft for providing rotation to an associated wiper blade, and said control circuit being operable to control the position of the wiper blades,

characterized in that said control circuit being operable to determined a target position for each of the wiper blades based upon desired acceleration, velocity, and deceleration values.

20. A windshield wiper system as defined in claim 19, wherein said control circuit is operable to determine torque values for each motor based upon said acceleration, velocity, and deceleration values.

21. A windshield wiper system as defined in claim 20, wherein aid control circuit is operable to determine said acceleration, velocity, and deceleration values in accordance with a user-selected wiper speed setting.

22. A windshield wiper system as define din claim 19, wherein said control circuit has an input for receiving a signal indicative of a user-selected wiper speed setting, and wherein said control circuit is operable to minimize said acceleration and deceleration values while permitting the wiper blades to complete a wiping cycle in the time allotted by the user-selected speed setting and while maintaining positional synchronism between the wiper blades.

23. In a windshield wiper system having a first motor, a second motor, and a control circuit having first and second outputs connected to said first and second motors, respectively,

said first and second motors each including an output shaft for providing rotation to an associated wiper blade, and said control circuit being operable measure the current used by said motors,

characterized in that said control circuit is operable to determine an environmental condition of the windshield in accordance with the measured current and is operable to change at least one of its outputs based upon said determined environmental condition.

24. A windshield wiper system as defined in claim 23, wherein said control circuit is operable to determine the environment condition using the measured current and at least one other measured parameters.

25. In a windshield wiper system having a first motor, a second motor, and a control circuit having first and second outputs connected to said first and second motors, respectively,

said first and second motors each including an output shaft for providing rotation to an associated wiper blade, and said control circuit being operable measure the current used by said motors,

characterized in that said control circuit is operable to determine an environmental condition of the windshield in accordance with the measure current and is operable to change at least one of its outputs based upon said determined environmental condition;

wherein said control circuit is operable to determine the environment condition using the measured current and at least one other measured parameter; and

wherein said other measured parameter is outside air temperature.

26. In a windshield washer system having a first motor, a second motor, a fluid reservoir, a pump, and a control circuit,

said first and second motors each including an output shaft for providing rotation to an associated wiper blade,

said control circuit being operable to control the spray of washer fluid onto the windshield,

characterized in that said control circuit being operable to control the spray of washer fluid onto the windshield in accordance with at least one measured parameter, wherein said control circuit is operable to track the position of the wiper blades and to spray washer fluid onto the windshield in synchronism with the wiper blades.

27. In a windshield wiper system having a first motor, a second motor, and a control circuit having first and second outputs connected to said first and second motors, respectively,

said first and second motors each including an output shaft for providing rotation to an associated wiper blade, wherein said motors are operable in an intermittent mode to reciprocate the wiper blades between an inboard and an outboard position,

characterized in that said control circuit is operable in an intermittent mode in which said control circuit operates to pause said motors when the wiper blades reach both said inboard and outboard positions.