Almost all automotive vehicles have a single or a pair of windshield wiper assemblies. These assemblies traditionally include rubber wiper blades mounted upon claw rackets. These claw rackets are pivotably attache to wiper arms mounted upon rotating shafts. The shafts are either directly driven by electric motors or driven by a single electric motor which actuates a series or parallel-coupled four bar linkage mechanism. It is further known to provide a wiper system, in combination with a wash device, to clean head lamps for automotive vehicles.

It is also common to employ a window wiper assembly for cleaning rear windows of automotive vehicles. Typically, these types of rear window wiper assemblies include a wiper blade mounted upon a bracket which is coupled to a wiper arm. The wiper arm is attache to a wiper shaft rotatably driven in a cyclical oscillating manner by a helical gear. A reversible, fractional horsepower, direct current electric motor serves to actuate the helical gear through an armature shaft-mounted worm gear enmeshed therewith. This type of rear window wiper arrangement is usually mounted upon a pivoting liftgate of a mini van, station wagon, sport-utility vehicle or the like. One such example is disclosed in U. S. Patent No.

5,519,258 entitled"System and Method for Controlling Vehicle Lift Gate Window Wiper"which issued to Stroven et al. on May 21,1996. Another conventional assembly inclues mounting the window wiper assembly through the rear window with an electromagnetic device mounted in the tailgate.

Some conventional vehicles also provide a rear window release lock or latch, actuated by a solenoid, which can be unlocked to allow for upward pivotal movement of a rear window in relation to the otherwise stationary

liftgate. In combination therewith, a separate liftgate lock is often mounted upon the liftgate door for fastening the liftgate to the body thereby preventing inadvertent pivotal opening. This liftgate lock is traditionally operated by manual key or handle rotation, or through a separate electric motor or solenoid. Separate motors or solenoids are commonly required to actuate these various locks and the wiper. The traditional need for such a multiplicity of electromagnetic devices has increased the automotive vehicle weight and cost while further proving difficult to package within the often small spaces provided. This added weight is especially detrimental when the window wiper mechanism, rear window lock and liftgate lock, as well as their distinct respective electromagnetic devices, are all incorporated within the pivoting liftgate. Not only is the piece cost increased due to this multiplicity of electromagnetic devices, but the assembly cost, part number proliferation and handling costs, electric wiring costs, objectional motor noise, and failure modes are increased.

Furthermore, U. S. Patent No. 3,688,332 entitled"Mechanism for Opening and Closing a Cover for a Concealed Windshield Wiper System" which issued to Bellware on September 5,1972, discloses a windshield wiper driven by an electric motor and an interruptable driving connection controlled by a separate electromagnet. This device further empioyed levers and pivot pins to open and close a cover.

More recently, WO 96/33891 entitled"Multi-Functional Apparats Employing an Intermittent Motion Mechanism,"WO 96/33893 entitled "Multi-Functional Apparats Employing an Electromagnetic Device,"and WO 96/33892 entitled"Control System for an Automotive Vehicle Multi- Functional Apparatus,"all of which were published on October 31,1996, disclose a significantly improved system wherein a single electromagnetic device can selectively operate intermittent motion mechanisms coupled to a window wiper, a door lock, a window release lock and the like.

Notwithstanding, these devices and the conventional design of placing the window wiper assembly through the rear windows require further refinement and improvement. For example, conventional designs mounted through a

liftgate door have reduced flexibility, restricted wiper patterns, and higher cost. Additionally, conventional window washer assemblies mounted through the rear window lack the ability to be used with multi-functional apparatuses.

SUMMARY OF THE INVENTION In accordance with the present invention, the preferred embodiment of a window wiper output release apparats, output release employs an electromagnetic device which selectively rotates a rotatable member which can removably engage a receiving member which moves with a rear window. In another aspect of the present invention, the electromagnetic device can accomplis several other functions including releasing a door latch or lock and releasing a window latch.

The window wiper output release apparats, release output of the present invention is advantageous over conventional systems since the pèsent invention embodies the ability to place the window wiper in the park position which prohibits the wiper from moving on the glass when the rear window is lifted. In addition, the removable feature of the present invention acts in conjunction with the multi-functional apparats to allow for other functions to be performed without the necessity for separate rear wiper motors, liftgate lock motors and rear window lock solenoids. In addition, the window wiper is placed in the park position when the rear window is open, thereby prohibiting the wiper from moving out of its synchronous position. Accordingly, the present invention reduces piece costs, assembly costs, handling costs, and wire costs. In addition, the present invention reduces weight and packaging space requirements while increasing the electrical and mechanicai reliability of effected systems as well as flexibility. Finally, the additional avantages and features of the present invention become apparent from the following description and dependant claims, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a rear elevational view showing the preferred embodiment of a window wiper output release apparats of the present invention; Figure 2 is a side elevational view, partially in section, showing the preferred embodiment of a window wiper output release apparats of the present invention; Figure 3 is a rear elevational view with portions broken away therefrom showing a multi-functional apparats employed with a preferred embodiment of a window wiper output release; Figure 4 is a front perspective view showing of an intermittent motion mechanism employed with preferred embodiment of a window wiper output release, dispose in a disengaged position; Figure 5 is a rear perspective view of a gear/cam with clutch in an engaged position; Figure 5a is an exploded view of a gear/cam with clutch in a partially engaged position.

Figure 6 is a perspective view showing the preferred embodiment gear drive preferred embodiment of a window wiper output release; Figure 7 is a rear elevational view showing the gear drive preferred embodiment of a window wiper output release; Figure 8 is a cross-sectional view, showing the preferred embodiment of a window wiper output release; Figure 9 is a fragmentary view, showing the receiver employed in the preferred embodiment of a window wiper output release of the preferred embodiment of the receiver; Figure 10 is a cross-sectional view, showing the preferred embodiment of a window wiper output release; Figure 11 is a fragmentary and exploded perspective view showing the self-locking feature of the preferred embodiment of a window wiper output release in a disengaged position;

Figure 12 shows a top elevational view showing a mounting plate and the self-locking feature of the preferred embodiment of a window wiper output release; Figure 13 is an exploded perspective view showing the self-locking feature of the preferred embodiment of a window wiper output release; Figure 14 shows a cross-sectional view, showing the self-locking feature of the preferred embodiment of a window wiper output release; Figure 15 is a fragmente side elevational view showing the receiver of the preferred embodiment of a window wiper output release; and Figure 16 is a cross-sectional view, showing the preferred embodiment of a window wiper output release in a partially engaged position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An automotive vehicle, such as a mini-van, sport utility vehicle, or the like, has a rear liftgate door 12 which when pivoted to an open position, a cargo space, or passenger compartment is accessible from behind the vehicle. Such an arrangement is shown in FIGS. 1 and 2. Liftgate 12 has a rear window or backlite 10 which is pivotal between a closed position, substantially flush with the outer surface of liftgate 10, to an open position, about a generally horizontal pivot access.

A multi-functional apparats 16 is mounted upon an inner surface of liftgate 12. The majority of apparats 16 is hidden by an interior trim panel (not show). Apparats 16 inclues a central drive and power transmission unit 43 (Figure 3).

The construction of central drive and power transmission unit 43 is best illustrated in Figure 3. An electric motor 51 is of a conventional 12 volt fractional horsepower, dc electromagnetic variety having a metallic motor housing 53 within which are stationary permanent magnets 55, a rotatable armature 57 with wire windings. Metallic housing 93 also contains a rotatable armature. Shaft 59 is joined to armature 57, a commutator 61 electrically connecte to the wire windings and rotatable with armature shaft

59, a brush card assembly 63 and various electronic components, bushings and retainers. It will be appreciated that other electric motor constructions can readily be substituted for that shown. A worm gear segment 65 is provided upon a portion of armature shaft 59 extending beyond motor housing 53.

A gear housing 71 is also provided for receiving worm gear segment 65 and the immediately adjacent portions of armature shaft 59. A main helical worm gear 73 is also housed and rotatably journaled within gear housing 71. Gear housing 71 is preferably made from cast aluminum. A plurality of knurled steel journaling pins 75 are press fit or otherwise attache within machine openings of gear housing 71. The placement of these openings in relation to each other is important. Pins 75 can alternately be molded as part of plastic gears and cams.

Helical gear 73 has an external set of helically oriente teeth 77 projecting entirely therearound for meshing with worm gear segment 65.

A drum 79 is mounted upon a face of helical gear 73 for rotating therewith.

Drum 79 has a partially circuiar peripheral surface 81 interrupted by a clearance indentation 83. Drum 79 and helical gear 73 are coaxially aligned for rotation about their respective journaling pin 75. A drive pin 85 projects from a face of helical gear 73 substantially parallel to the adjacent journaling pin 75. Drive pin 85 has a cylindrical driving interface surface 87 thereabout. Of course, a rotatable sleeve may alternately surround drive pin 85. Other alternate driving interface means may be employed such as an integrally molded finger, screw, rivet, spring, rib, plural projections or other similar formations protruding from a face of peripheral portion of helical gear 73. Helical gear 73 is preferably injection molded from a polymeric material such as acetyl. An electrically conductive feedback disk is retained to an inside face of helical gear 73 through ultrasonically rolied welding or insert molding. The feedback disk is comprise of a set of copper alloy or brass alloy stamped contacts which are provided with differing conductive and nonconductive patterns depending on the specific positional ranges as will be discussed in greater detail hereinafter.

A power transmission assembly of central drive and power transmission unit 43 employs three intermittent rotary motion mechanisms or cams 103,105 and 107. Each cam has a single, linear, external open channel 109 defined by driven interfacing surfaces or walls therein. Driving interface surface 87 of drive pin 85 is selectively engageable against the walls defining channels 109 of each cam. Each cam is rotatable about its respective journaling pin 75. Furthermore, partially circular external surfaces 111 of each cam register with the partially circular peripheral surface 81 of drum 79. A relatively tight tolerance on these registering surfaces of about 1-2 thousandths of an inch is preferably used. Thus, unless each cam is aligned with indentation 83 of drum 79, partially circular peripheral surface 81 of drum 79 will act to prevent rotation of each cam. However, when indentation 83 of drum 79 aligns with an individual cam, concurrently with drive pin 85 engaging within a channel 109 of the same cam, continued rotation of helical gear 73 will cause the selectively coupled cam to rotate therewith. Moreover, the selectively coupled cam will have increased rotational acceleration as drive pin 85 moves closer to journaling pin 75 within channel 109. This rotational acceleration, then deceleration, achieves a desirable inertial ramping up and ramping down effect such that potentially harmful inertial stresses and cyclical fatigue within the device coupled thereto are avoided. The diameter of drive pin 85 should match channel 109 width within half a thousandth of an inch.

Cam 103 additionally has a spur gear 117 stacked coaxially thereupon for simultaneous movement therewith. Spur gear 117 has a peripheral set of teeth 119 extending entirely therearound for enmeshing with a mating external set of teeth 121 extending entirely around a driven pinion gear 123.

Pinion gear 123 rotates the output shaft. The window wiper shaft 125 extends from a rear face of pinion gear 123 for moving in concert therewith.

Wiper shaft 125 is attache to pinion gear 123 through rivets, insert molding, knurled press fitting, et cetera. Wiper shaft is preferably made from cold rolled steel. The system is designed to oscillate wiper shaft 125

at forty-five cycles per minute (round trip) but other cycle frequencies can be achieved.

In an alternate embodiment, referring to Figures 4-5a, cams 103,105 and 107 and the and the associated parts are replace by a first intermittent motion mechanism 132 which inclues a cam follower disk 126, a cam disk 127, a driving sleeve 128, a helically wound compression spring 129 and a spring retainer 130, all of which generally surround wiper shaft 125. An annular bushing segment 141 of gear 131 coaxially surrounds a proximal end of wiper shaft 125 and rotatably supports wiper shaft 125 concentrically with gear 131 and a bifurcated end 143 of driving sleeve 140. A pair of lock or snap rings 145 are longitudinally positioned on either side of bushing segment 141 for maintaining the positional relationship of wiper shaft 125 relative to gear 131 and the adjacent gear housing cover.

A cylindrical pin is positioned through a transverse bore in wiper shaft 125.

The pin serves to longitudinally secure spring retainer 130 relative to wiper shaft 125.

Cam follower disk 126 has a pair of stepped annular structures 201 and 203 with a central common aperture pressfit or otherwise rotationally secured upon wiper shaft 125. A motion limiting primary tab 207 transversely depends from structure 203 and is defined by a pair of flat walls perpendiculariy extending in a longitudinal direction from structure 201. A supplemental locking tab 211 peripherally depends from structure 201. A wedge surface of tab 211 defines a lock moving ramp which allows rotation of the wiper shaft past a lock for subsequent engagement. An abutting wall is also provided on secondary tab 211 and is generally coplanar with wall 209 of primary tab 207. The abutting wall acts as the park position locking surface.

Three finger receptacles are recessed into a backside of cam follower disk 126. Three fingers are engageable within the finger receptacles. The fingers and receptacles are not equidistant from each other and they have different sizes, in order to allow engagement of the cam with cam foilower

126 in only one rotational position. A backface of the cam disk further has a longitudinal depression intersecting a central aperture.

Driving sleeve 128 has a hollow, circular-cylindrical shaped body 251 which receives compression spring 129, spring retainer 130 and bushing 141. An annular shoulder 253 is dispose on said body 251 longitudinally opposite from bifurcated end 143. A circular aperture longitudinally extends through shoulder 253 with clearance around wiper shaft 125. Compression spring 129 is operably compresse between an inside surface of shoulder 253 and spring retainer 130. Tongues are symmetrically dispose on either side of the aperture 255 and longitudinally depend from shoulder 253. The tongues engage with the groove of cam disk 123 so as to rotate cam 123 in concert with rotation of driving sleeve 128. Bifurcated end 143 of driving sleeve 125 fits within a pair of arcuate slots 271 of gear 73. Accordingly, when the electric motor is selectively energized, an armature 281 and worm gear segment will rotate gear 73 a predetermined angular or rotational amount and thereby concurrently rotating driving sleeve 128 and cam disk 127.

A locking sleeve 301 has a ring segment 305 and a lock housing segment 307. Ring segment 305 concentrically surrounds wiper shaft 81 and is longitudinally trapped for movement between cam disk 123 and driving sleeve 128. Lock housing segment 307 mates with a transversely offset cavity of cover 147 in a keyhole-like manner such that lock sleeve 301 is prevented from rotation but is allowed to longitudinally move in a linear manner. A shaft lock 303 is movably dispose in lock housing segment 307. A helically wound compression spring or resilient member 311 is compresse between a metallic push nut 313, having a set of inwardly projecting and angled fingers, and a facing surface of lock housing segment 307. Spring 311 serves to linearly and longitudinally bias lock 303 relative to locking sleeve 301 when lock 303 rides against supplemental tab 211. Lock 303 is further defined by a head 315 and a circular-cylindrical pedestal 317.

The operation of first intermittent motion mechanism 132 of the present embodiment can best be understood as follows. First intermittent motion mechanism 132 essentially acts as a clutch in selectively engaging and disengaging wiper shaft 125 from gear 131. The fingers of cam disk 127 are fully engaged within finger receptacles cam follower disk 201 when the electric motor has been energized to rotate gear 131 within a window wiping positional range and between the window wiping positional range and the initial park position. In this engaged clutch position, spring 129 biases driving sleeve 128, locking sleeve 301 and cam disk 127 away from gear 131 such that cam follower disk 126 and wiper shaft 125 will rotate and oscillate concurrent with rotation and oscillation of gear 131.

In the clutch disengaged position the flat wall 209 of the cam follower disk primary tab 207 abuts against a wiping range stop the cover such that cam follower disk 126 and wiper shaft 125 are prevented from further rotation. However, the electric motor selectively further continues the rotation of gear 131 along the rotational direction thereby causing coincidental rotation of driving sleeve 128 and cam disk 127. This continued rotational movement causes the inclining surface of each cam disk finger to longitudinally push cam disk 123, lock sleeve 301 and driving sleeve 128 toward gear 131. This also serves to compress spring 129.

Bifurcated end 143 of driving sleeve 128 passes through gear 131 in this state. Thus, cam follower disk 126 and cam disk 127 are effectively separated. Gear 131 can further rotate to various other positional ranges as previously discussed while wiper shaft 125 remains in a park position.

The clutch disengaged movement further serves to lock or pin wiper shaft 125 in the park position by abutting head 314 of lock 303 against the abutting wall of secondary locking tab 211. Gear 131, driving sleeve 128 and cam disk 127 are further rotated to an initial park position after the clutch is disengaged. Lock 303 is released from tab 211 when the rotational direction of gear 131 is reverse back past through the park position so that cam disk 127 rengages with cam follower disk 201 for

concerte movement. This causes head 315 of lock 303 to longitudinally move free of tab 211.

Referring now to Figures 6 and 7, an end of shaft 125 opposite to helical gear 131 has a spline 38 with a plurality of protrusions 24 equally dispose around shaft 125 with alternating depressions 22. A terminal end of Spline 38 is tapered 26 to form a bridge 23 that is equal in diameter to shaft 125.

Referring to Figures 8-16, a receiver 42 is defined by a plurality of release lobe features 46 equally dispose in a circular manne to form an inner receptacle 50, a plurality of recesses 35 and alternating protrusions 32. Each release lobe 46 has a lead in 44 defining a lead in opening to receptacle 50. Release lobes 46 of receiver 42 penetrate through an aperture in rear window 10. Receiver 42 is contained within housing 59 which is mounted to a plate 57 by mounting bolts 53. Plate 57 is alternatively mounted to rear window 10 by mounting bolts 53 or adhesive.

Receiver 42 has a flange 54 encircling its circumference. Flange 54 has a plurality of serrations 33 which are equally spaced and can interlock with a mounting plate 57. Mounting plate 57 contains a plurality of serrations 59 defining an aperture 61. It should be understood that serrations 59 may be contained as part of an insert of mounting plate 57. Housing 59 also contains a plurality of springs 65 which contacts flange 54 at nylon bushing 64 or other friction material. Spring 64 is not fixed at its end opposite to nylon bushing 64. Furthermore, receiver 42 exits housing 59 to join wiper 75. Bushing 71 also forms a seal where receiver 42 exits housing 59.

Receiver 42 attaches to wiper 75 by bolt and spline 74.

The operation of the multi-functional apparats will now be discussed in further detail. The operation of the window wiper system release apparats is rotational movement of shaft 125 is transmitted through spline 38 when electromagnetic device is operating. Referring specifically to Figures 10 and 16, spline 38 engages with release lobes 46 when rear window 10 is pushed into a locking position. Lead in 44 accepts spline 38 as spline 38 engages lobes 42. On complete engagement, as referenced in

Figure 10, spline 38 nests within receptacle 50. During engagement, spring 65 is compresse and flange 54 is disengaged from plate 57. After engagement, rotational movement of shaft 125 is transmitted through spline 38 through receiver 42 to wiper 75. As referred in Figure 8, upon disengagement of spline 38 from receiver 42 when rear view window 10 is open, flange 54 is urged forward by spring 65. Flange 54 engages plate 57 thereby allowing for locking of serrate surface 33 to serrate surface 59.

While various embodiments of the present invention have been described, it will be appreciated that various modifications can be made. For example spline 38 can have offset lobes which are equal in number to the clutch of the drive shaft. Additionally, the serrate teeth can have a non- uniform spacing which would limit re-engagement to the proper orientation.

In addition, the clutch may be moved to a position exterior the tailgate. In addition, the serrate teeth of the locking device may be modifie to have interlocking teeth which prohibit rotation of the wiper when the rear window is open. In addition, various materials have been disclosed in an exemplary fashion, however, other materials may, of course, be employed. It is intended by the following claims to cover these and any other departures from the disclosed embodiments which fall within the true spirit of this invention.