Windshield wiper motor link depressed park mechanism

Claim 2

A windshield wiper drive mechanism having a shaft rotatable by a reversible motor, a wiper motor output arm on the shaft, a drivepin fixed to the output arm, a driving link adapted to be coupled to a wiper arm linkage, and an eccentric interposed between the output arm and the driving link, the eccentric being rotatable about the drivepin and the driving link being rotatably coupled to the eccentric for rotation about an axis displaced from the axis of rotation of the eccentric about the drivepin, the effective output arm radius in normal wipe pattern of a wiper arm being the distance from the shaft axis to the drivepin and in depressed park position being this distance increased by the distance between the drivepin and the axis of the driving link on the eccentric, wherein the improvement comprises: a double latch device carried by the eccentric having a pair of spring-loaded latch elements both of which lock the output arm to the eccentric in the depressed park or maximum radius condition of the output arm, the spring-loaded latch elements comprising latch pins located on diametrically opposite sides of the drivepin, the first one of the latch elements to unlock upon initiation of a run cycle being located on the outboard side of the drivepin relative to the motor shaft, the second latch element prior to initiation of the run cycle being located between the drivepin and shaft, the output arm having a ramp engageable with the first one of the latch elements upon initiation of the run cycle to drive the latter against the spring-loading to unlocked position, upon initiation of the run cycle from depressed park position of the wiper arm the first one of the latch elements unlocking while the second remains locked until the end of the first half of the run cycle is reached to restore the effective output arm radius to normal wipe pattern radius, the second latch element then unlocking the eccentric from the arm and locking the eccentric to the drivelink, with the eccentric locked to the drivelink relative rotation of the eccentric about the drivepin occurs and a normal wiper pattern sweep of the wiper arm is obtained.

Claim 3

A windshield wiper arm drive mechanism according to claim 1, in which: the second latch element is spring-loaded toward the driving link and is held in engagement with the output arm by its engagement with the underside of the driving link until the latter is rotated to a position in which the second latch element is aligned with an aperture in the driving link, the aperture having a ramp contiguous thereto effective to cam the second latch element out of the aperture upon reversal of the direction of rotation of the output arm.

Claim 4

A windshield wiper drive mechanism having a shaft rotatable by a reversible motor, a crank arm fixedly secured to the shaft, a drivepin on the crank arm, an eccentric rotatably journalled on the drivepin, the axis of rotation of the eccentric about the drivepin being in fixed, spaced and parallel relation to the axis of the shaft, and a driving link rotatably coupled at one end to the eccentric and at its other end to a wiper arm linkage, wherein the improvement comprises: a latch means including latch elements shiftable in directions paralleling the drivepin axis to fixedly connect the eccentric to the crank arm or to fixedly connect the eccentric to the driving link depending on the direction of rotation of the crank arm, the latch elements comprising a pair of biased latch pins slidable in the eccentric and located on diametrically opposite sides of the drivepin about which the eccentric is rotatable, at least one of the pins having abutting engAgement with an abutment on the crank arm in one position of the eccentric and the other having abutting engagement with an abutment on the driving link in a second position of the eccentric, the distance between the axis of rotation of the crank arm and the axis of rotation of the driving link on the eccentric and therefor the effective length of the crank arm being controlled by the latched relationship of the eccentric to the driving link or to the crank arm, respectively.

Claim 5

A windshield wiper drive mechanism having a shaft rotatable by a reversible motor, a crank arm fixedly secured to the shaft, a drivepin on the crank arm, an eccentric rotatably journalled on the drivepin, the axis of rotation of the eccentric about the drivepin being in fixed, spaced and parallel relation to the axis of the shaft, and a driving link rotatably coupled at one end to the eccentric and at its other end to a wiper arm linkage, wherein the improvement comprises: a latch means including latch elements shiftable in directions paralleling the drivepin axis to fixedly connect the eccentric to the crank arm or to fixedly connect the eccentric to the driving link depending on the direction of rotation of the crank arm, the latch elements comprising a pair of biased latch pins slidable in the eccentric and located on diametrically opposite sides of the drivepin about which the eccentric is rotatable, at least one of the pins having abutting engAgement with an abutment on the crank arm in one position of the eccentric and the other having abutting engagement with an abutment on the driving link in a second position of the eccentric, the distance between the axis of rotation of the crank arm and the axis of rotation of the driving link on the eccentric and therefor the effective length of the crank arm being controlled by the latched relationship of the eccentric to the driving link or to the crank arm, respectively.

Claim 6

A windshield wiper drive mechanism having a shaft rotatable by a reversible motor, a crank arm fixedly secured to the shaft, a drivepin on the crank arm, an eccentric rotatably journalled on the drivepin, the axis of rotation of the eccentric about the drivepin being in fixed, spaced and parallel relation to the axis of the shaft, and a driving link rotatably coupled at one end to the eccentric and at its other end to a wiper arm linkage, wherein the improvement comprises: a latch means including latch elements shiftable in directions paralleling the drivepin axis to fixedly connect the eccentric to the crank arm or to fixedly connect the eccentric to the driving link depending on the direction of rotation of the crank arm, the distance between the axis of rotation of the crank arm and the axis of rotation of the driving link on the eccentric and therefor the effective length of the crank arm being controlled by the latched relationship of the eccentric to the driving link or to the crank arm, respectively, the latch elements comprising a pair of latch pins slidably journalled in the eccentric on opposite sides of the axis of rotation of the latter about the drivepin, a first spring means biasing one of the latch pins toward the drivelink and a second spring means biasing the other latch pin toward the crank arms, a first abutment on the driving link positioned to abut the one latch pin and having a ramp leading thereto, the first abutment being effective to engage the one latch pin to lock the eccentric to the driving link upon rotation of the crank arm in normal windshield wiper oscillation drive direction and the ramp leading thereto being effective to cam the latch pin out of locking position upon reverse rotation of the crank arm, and a second abutment on the crank arm positioned to abut the other latch pin and having a ramp leading thereto, the second abutment being effective to engage the other latch pin to lock the eccentric to the crank arm upon reverse rotation of the latter which locking action occurs at a position of the wiper arm corresponding to the start of a wipe cycle, further rotation in reverse direction causing the eccentric to bodily shift the driving link away from the crank arm axis of rotation to drive the wiper arm below its normal wipe cycle start position into a depressed park position.

Claim 7

A windshield wiper drive mechanism having a shaft rotatable by a reversible motor, a crank arm fixedly secured to the shaft, a drivepin on the crank arm, an eccentric rotatably journalled on the drivepin, the axis of rotation of the eccentric about the drivepin being in fixed, spaced and parallel relation to the axis of the shaft, and a driving link rotatably coupled at one end to the eccentric and at its other end to a wiper arm linkage, wherein the improvement comprises: a latch means including latch elements shiftable in directions paralleling the drivepin axis to fixedly connect the eccentric to the crank arm or to fixedly connect the eccentric to the driving link depending on the direction of rotation of the crank arm, the distance between the axis of rotation of the crank arm and the axis of rotation of the driving link on the eccentric and therefor the effective length of the crank arm being controlled by the latched relationship of the eccentric to the driving link or to the crank arm, respectively, the latch elements comprising a pair of latch pins slidably journalled in the eccentric on opposite sides of the axis of rotation of the latter about the drivepin, a first spring means biasing one of the latch pins toward the drivelink and a second spring means biasing the other latch pin toward the crank arms, a first abutment on the driving link positioned to abut the one latch pin and having a ramp leading thereto, the first abutment being effective to engage the one latch pin to lock the eccentric to the driving link upon rotation of the crank arm in normal windshield wiper oscillation drive direction and the ramp leading thereto being effective to cam the latch pin out of locking position upon reverse rotation of the crank arm, and a second abutment on the crank arm positioned to abut the other latch pin and having a ramp leading thereto, the second abutment being effective to engage the other latch pin to lock the eccentric to the crank arm upon reverse rotation of the latter which locking action occurs at a position of the wiper arm corresponding to the start of a wipe cycle, further rotation in reverse direction causing the eccentric to bodily shift the driving link away from the crank arm axis of rotation to drive the wiper arm below its normal wipe cycle start position into a depressed park position.