Vehicle headlamp wiper assembly

Claim 2

A vehicle headlamp wiper assembly comprising a housing, a drive shaft rotatably supported by said housing, a wiper blade affixed to said drive shaft for rotation therewith, first and second cylinders associated with said housing, first and second pistons reciprocably mounted in said first and second cylinders respectively, power transmission means drivingly connecting said first and second pistons to said drive shaft for imparting rotation thereto upon reciprocation of said pistons, and valve means associated with said cylinders and operatively connected to said drive shaft for alternatively communicating said first and second cylinders with a vacuum source in response to movement of said wiper blade to said predetermined angular positions, said valve means including first and second valves associated with said first and second cylinders, respectively, one of said valves being opened to communicate the associated cylinder with said vacuum source when the other of said valves is closed to substantially seal its associated cylinder from said vacuum source, said valve means including an actuator rod reciprocally mounted in said housing between said first and second valves and movable between a first position wherein said first valve is opened and a second position wherein said second valve is opened, an oscillatable actuation shaft carried by said housing and disposed generally normal to said actuator rod, first lost motion connecting means including a first lost motion connection between said drive shaft and actuation shaft, and second lost motion connection means including a second lost motion connection between said actuation shaft and said actuator rod.

Claim 3

The combination of claim 1 including Snap-action means operatively associated with said housing and said oscillatable shaft for snap-shifting said shaft to its limit positions of oscillation in response to said shaft being rotated past a predetermined central position of oscillation toward said limit positions.

Claim 4

A vehicle headlamp wiper assembly comprising a housing, a drive shaft rotatably supported by said housing, a wiper blade affixed to said drive shaft for rotation therewith, first and second cylinders associated with said housing, first and second pistons reciprocably mounted in said first and second cylinders respectively, power transmission means drivingly connecting said first and second pistons to said drive shaft for imparting rotation thereto upon reciprocation of said pistons, and valve means associated with said cylinders and operatively connected to said drive shaft for alternatively communicating said first and second cylinders with a vacuum source in response to movement of said wiper blade to said predetermined angular positions, said valve means including first and second valves associated with said first and second cylinders respectively, one of said valves being opened to communicate the associated cylinder with said vacuum source when the other of said valves is closed to substantially seal its associated cylinder from said vacuum source, said valve means including means coupling said first and second valves to said drive shaft, said coupling means including lost motion means for allowing rotation of said drive shaft and wiper blade through an angle between said predetermined positions without affecting operation of said first and second valves, said coupling means further including snap-action means associated with said lost motion means for effecting rapid simultaneous operation of said first and second valves upon movement of said wiper blade to said predetermined angular positions, said valve means including an actuator rod reciprocably mounted between said first and second valves and movable between a first position wherein said first valve is opened and a second position wherein said second valve is opened, said coupling means including a rotatable actuation shaft carried by said housing and generally perpendicular to said actuator rod, said lost motion means including a first lost motion connection between said drive shaft and actuation shaft, and a second lost motion connection between said actuation shaft and said actuator rod.

Claim 5

A vehicle headlamp wiper assembly comprising a housing, a drive shaft rotatably supported by said housing, a wiper blade affixed to said drive shaft for rotation therewith, first and second cylinders associated with said housing, first and second pistons reciprocably mounted in said first and second cylinders respectively, power transmission means drivingly connecting said first and second pistons to said drive shaft for imparting rotation thereto upon reciprocation of said pistons, and valve means associated with said cylinders and operatively connected to said drive shaft for alternatively communicating said first and second cylinders with a vacuum source in response to movement of said wiper blade to said predetermined angular positions, said valve means including first and second valves associated with said first and second cylinders respectively, one of said valves being opened to communicate the associated cylinder with said vacuum source when the other of said valves is closed to substantially seal its associated cylinder from said vacuum source, said valve means including means coupling said first and second valves to said drive shaft, said coupling means including lost motion means for allowing rotation of said drive shaft and wiper blade through an angle between said predetermined positions without affecting operation of said first and second valves, said coupling means further including snap-action means associated with said lost motion means for effecting rapid simultaneous operation of said first and second valves upon movement of said wiper blade to said predetermined angular positions, said valve means including an actuator rod reciprocably mounted between said first and second valves and movable between a first position wherein said first valve is opened and a second position wherein said second valve is opened, said coupling means including a rotatable actuation shaft carried by said housing and generally perpendicular to said actuator rod, said lost motion means including a first lost motion connection between said drive shaft and actuation shaft, and a second lost motion connection between said actuation shaft and said actuator rod.

Claim 6

The structure set forth in claim 3 wherein said snap-action means is associated with said actuation shaft intermediate said first and second lost motion connections.

Claim 7

The structure set forth in claim 1 wherein said power transmission means includes an elongated, flexible member with a first end attached to said first piston and a second end attached to said second piston, and a rotary drive member affixed to said drive shaft, said elongated flexible member being in driving engagement with said rotary drive member to effect rotation of said drive shaft.

Claim 8

The structure set forth in claim 5 wherein said cylinders are in spaced parallel relation to each other, said elongated flexible member being wrapped around said rotary drive member intermediate said first and second ends.

Claim 9

The structure set forth in claim 6 wherein said rotary drive member includes a plurality of sprocket teeth in operative engagement with openings in said elongated flexible member.