March 24, 1964 A. E.

LEININGER 3,125,777
WINDSHIELD WIPER MECHANISM
lled Dec. 22, 1961 I5 Sheets-Sheet 1
 3,125,777
United States Patent "Ice Patented Mar. 2.4, 1964
1 2
11 and 12, respectively. The reciprocal link 14 is at
3,125,777 ' tached directly to the rocker link 15 which is rigidly
WINDSHEELD WIPER MECSM mounted on the shaft of the driving means 2. The rocker
Alfred E. Leininger, Ypsilanti, Mich, assignor to Ford link 15 has two rocker arms 16 and 17. The arms 16
Motor Company, Dearborn, Mich, a corporation of and '17 are different in length, and the intersection of
Delaware
Filed Dec. 22, 1961, Ser. No. 161,479 their longitudinal axis makes an acute angle.
7 Claims. (Cl. 1525tl.14) The reciprocal link 13 is pivotally attached at the pivot
point 18 to a ?rst idler link or variable acceleration link
This invention relates to window cleaning devices and, 19. The ?rst variable acceleration link 19 is pivotally
in particular, relates to a novel and improved cleaning 10 attached at the pivot point 20 to a second idler link or
device for the windshield of an automotive vehicle. variable acceleration link 21. The second variable ac
The windshield wiper, which is the subject of this in celeration link 21 is pivotally attached at pivot point 22
vention, utilizes two pivoted wiper means, each having a to the body of the automobile. The ?rst variable accelera
wiper blade. The wiper blades are in an overlapping rela tion link 19 is pivotally attached at pivot point 23 to the
tionship when the wiper means are at the center of the 15 rocker arm 16.
windshield adjacent to the automobile body. The two The rocker arm 17, reciprocal link 14 and the arm 12
wiper means are connected to a linkage means comprising comprise a linkage or more particularly a four-bar link
two linkages. One of the linkages is a simple four-bar age 6 which drives the wiper means 4. The rocker arm
linkage which drives one of the wiper means at a ?rst ac 16, ?rst variable acceleration link \19, the second variable
celeration. The other linkage is an idler linkage or a 20 acceleration link 21, the reciprocal lint 13 and the arm
variable acceleration linkage which drives the associated 11 comprise a variable acceleration linkage or idler
wiper means at a second acceleration which is different linkage 5. This linkage will drive the attached wiper
than the ?rst acceleration. Both linkages are connected means 3 at an acceleration different from the acceleration
to a motor having a reciprocating action. The motor caused by the four-bar linkage 6 connected to the wiper
actuates the linkages so that the overlapping wiper blades 25 means 11.
Iwill freely traverse the windshield. FIGURE 1 shows the windshield wiper and its asso
\It is the general object of this invention to provide an ciated linkages at the zero position of the wiper traverse.
improved window wiper. The wiper traverse is de?ned as the total angle of travel
Another object of the invention is the provision of a experienced by the wiper blade in moving from the center
window wiper that will clean a large area of an automobile 30 of the Windshield adjacent- the automobile body to the
windshield. outer extremity of the windshield. For the purpose of
Another object of the invention is the provision of this description, a smaller traverse than is usual is con
a window wiper that will clean a continuous area across sidered. It should be noted that the windshield wiper
the greater part of an automobile windshield. blades are in an overlapping relationship when in the zero
Other objects and advantages will become apparent position of the wiper traverse.
when reference is made to the following detailed de Referring to FIGURE 2, when the windshield wiper is
scription and the accompanying drawings, wherein: turned on by the operator of the automotive vehicle, the
FIGURE 1 is a front view of the automobile wind rocker arm 17 will drive the reciprocal link 14, arm 12
shield and wiper means wherein a portion of the auto and the wiper means 4- at an acceleration which initially
mobile body has been removed so that the linkage ar 40 exceeds the acceleration that the variable acceleration
rangement of the windshield wiper is visible; linkage 11, '13, 16, 19 and 21 transmits to the wiper means
FIGURE 2 is a view similar to FIGURE 1 showing the 4. FliGURE 2 shows the position of the windshield wiper
windshield wiper after approximately one-third of the means and the associated linkages after approximately
\wiper traverse has elapsed; one~third of the wiper traverse has been completed. .It
FIGURE 3 is a View similar to FIGURE 1 showing 45 should be noted that during the ?rst one-third of the
the windshield wiper after approximately two~thirds of traverse, the four-bar linkage 12, 14 and 117 causes a
the wiper traverse has elapsed; greater acceleration than the variable acceleration link
FIGURE 4 is a view similar to FIGURE 1 showing age 11, 13, 16, 19 and 21; this results in the wiper means
the windshield wiper approaching the completion of the 4 initially experiencing a greater total displacement than
wiper traverse; and, the wiper means 3.
FIGURE 5 is a front view of an alternative linkage for FIGURE 3 shows the windshield wiper means and the
driving the wiper means of the windshield wiper. associated linkages after approximately two-thirds of the
A windshield wiper 1 has the wiper means 3 and 4 wiper traverse has been completed. At this point, the
which are operated by a linkage means comprising link wiper means 4, which is attached to the four-bar linkage
ages 5 and 6. This linkage means is connected to a 55 12, 14 and 17, has begun to decelerate relative to the
centrally located driving means .2. The driving means 2 wiper means 3 driven by the variable acceleration link
may include an electric or vacuum-operated reciprocating ages 11, 13, 16, 19 and 21. The wiper means 3 lags
motor. The wiper means 3 and 4- comprise wiper blades slightly behind the wiper means 4.
7 pivotally attached in the usual way to wiper arms 8. 7 FIGURE 4 shows a windshield Wiper and its associated
It should be noted that the wiper blades are in an over 60 linkage approaching the completion of the wiper traverse.
lapping relationship. The wiper arms 8 are rigidly It should be noted that the wiper blades reach the ex
mounted on the shafts 9 and 1G. The shafts 9 and 10 tremity of the traverse at approximately the same instant.
are free to rotate but ?xed against axial movement. Under ordinary circumstances the extremity of the traverse
The United States Patents 2,994,900 and 2,997,727 de would approach the extremity of the windshield.
scribe in detail the construction of two alternative wiper 65 After the completion of the wiper traverse the wiper
means. The particular wiper means described in these means 3 and 4 will return from the outer extremities of
patents could be utilized satisfactorily in the preferred the windshield to the central portion of the windshield
embodiment. adjacent the automobile body. The mode of operation
The linkage means, comprising the linkages 5 and 6, during the return of the Wiper means 3 and 4 is essen
has the arms 11 and 12 rigidly attached to the shafts 9 70 tially the reverse of the above-described Wiper traverse.
and 10, respectively. The reciprocal links 13 and l14 are The wiper means 3, driven by the variable acceleration
pivotally attached in a conventional manner to the arms linkage 11, 13, 16, 19 and 21, will initially experience a
 3,125,777
Q (it
high acceleration relative to the wiper means 4, driven arrive at the extremity of the Windshield at approximately
by the four-bar linkage 12, 14 and 17. During the ?nal the same instant as the Wiper means 4, driven by the re
portion of the return traverse, the wiper means 3 will ciprocal link 14. It should be noted that this embodi
decelerate relative to the deceleration of the wiper means ment accomplishes essentially the same result as the em
4. The wiper means 3, attached to the variable accelera bodiment shown, in FIGURE 1 with fewer links.
tion linkage, and the wiper means 4, attached to the four It should be obvious from the foregoing detailed de
bar linkage, will arrive at their center position at approxi scription that the different acceleration of the two link
mately the same instant. ages enables the wiper means to utilize overlapping wiper
In moving to the extremity of a wiper traverse and re blades. The provision of overlapping Wiper blades en
turning, the pivot point 18' moves alon" an approximately ables the windshield Wiper to clean a larger area of the
elliptical path 18", 18", 18"" (FIGURE 1), While the windshield and to clean a large continuous area across
pivotal connection 25 moves along a circular path 25", the windshield. The foregoing results are accomplished
25', 25. It should be noted that when the rocker link without sacri?cing the advantages incident to a Wind
15 is at a zero position (FIGURE 1) the pivot point 18' shield wiper having its wiper blades at rest in the center
is in the vicinity of the apex of the elliptical path. When position of the windshield adjacent to the automobile
the pivot point 18' is in the vicinity of the apex, each de body.
gree of rotation of the rocker link 15 will cause a large It should be understood that the invention is not to be
vertical displacement and a. relatively small horizontal limited to the exact construction shown and described.
displacement of the pivot point 18. The vertical dis Various changes and modi?cations of the linkages and
placement of the pivot point 18' tends to cause the re the nature of the acceleration imparted by these linkages
ciprocal link 13 to experience a rotational displacement. may be made without departing from the spirit and scope
The ?rst and second variable acceleration links 19 and of the invention, as de?ned by the appended claims.
21, therefore, initially transmit a slight horizontal dis I claim:
placement and a relatively large angular displacement 1. In an automobile windshield wiper, the combination
through the pivot point 18 to the reciprocal link 13 per of at least two wiper means having overlapping blade por
degree of rocker link rotation. As the pivotal point 18' is tions, said wiper means attached to be moved over the
moved away from the apex of the elliptical path, the windshield to clean areas thereof, at least two shafts having
variable acceleration links 19 and 21 will transmit a said wiper means attached thereto, a linkage means con
greater horizontal displacement and a smaller angular nected to said shafts, a motor having a driving shaft con
displacement to the reciprocal link 13 per degree of rocker 30 nected to said linkage means for driving said linkage
link rotation. means, said linkage means including a four-bar linkage to
In comparison to the variable acceleration links 19 and drive one of said wiper means and a variable acceleration
21, the pivotal connection 25, which moves in a circular linkage to drive said other wiper means, said four-bar
path, transmits to the reciprocal link 14 a more constant linkage having a rocker link which is directly connected
horizontal and angular displacement per degree of rota to said driving shaft, a ?rst reciprocal link connected to
tion of the rocker link 15. During the ?rst portion of said rocker link and a driven arm connected to one of said
the wiper traverse the pivotal connection 25 transmits a shafts and said reciprocal link, said variable acceleration
greater horizontal displacement to the reciprocal link 14 linkage having a second rocker link connected directly to
than the pivotal connection 18' transmits to the recipro said driving shaft of said motor, a ?rst variable accelera
cal link 13, while during later portions of the wiper trav tion link connected to said second rocker link, a second
erse the converse is true. reciprocal link connected to said variable acceleration link
The horizontal displacement transmitted to the recipro and a second driven arm connected to said second recip
cal links 13 and 14 per degree of rocker link rotation will, rocal link and another of said shafts.
in part, determine the acceleration transmitted to the 2. In an automobile windshield wiper, the combination
arms 11 and 12. The proportioning of the links 11 to 19 45 of at least two wiper means having overlapping blade por
and the angular relationship of these links will determine tions, said wiper means attached to be moved over the
the exact nature of the acceleration transmitted from the windshield to clean areas thereof, at least two shafts hav
driving means 2 to the arms 11 and 12. ing said wiper means attached thereto, a linkage means
From the foregoing discussion, it is apparent that if connected to said shafts, a motor having a driving shaft
the pivotal connection 18 is at the apex of the elliptical connected to said linkage means for driving said linkage
path When the rocker link 15 (FIGURE 1) is in a zero means, said motor having a reciprocating movement, said
position, the arm 11 will virtually experience a dwell linkage means comprising a four-bar linkage to drive one
period before beginning to rotate. This is caused by the of said wiper means and a variable acceleration linkage
reciprocal link initially experiencing very little, if any, to drive said other wiper means, said four-bar linkage
horizontal displacement. having a ?rst rocker link which is directly connected to
It is within the scope of the invention to provide a said driving shaft, a ?rst reciprocal link connected to said
linkage such as the variable acceleration linkage, shown ?rst rocker link and a driven arm connected to one of said
in FIGURE 1, or more particularly to provide a variable shafts and said reciprocal link, said variable acceleration
acceleration linkage which will virtually experience an linkage having a second rocker link connected directly to
initial dwell period and then be driven at a higher ac 60 said driving shaft of said motor, a ?rst variable accelera
celeration than the four-bar linkage. tion link connected to said second rocker link, a second
FIGURE 5 shows such an alternative linkage for driv reciprocal link connected to said variable acceleration link
ing the wiper means 3. The rocker arm 16 in this em and a second driven arm connected to said second recipro
bodiment is pivotally attached to a slider link 30. The cal link and another of said shafts.
slider link 30 is slidably and rotatably mounted on the 65 3. In a windshield wiper, the combination of at least
automobile body by the slot 31 and the pin 32 which is two pivoted wiper means attached to be moved over the
rigidly attached to the automobile body. The slider link windshield to clean areas thereof, a ?rst reciprocal link
30 is pivotally attached to the reciprocal link 13 at the means for driving one of said wiper means, said ?rst re
pivotal point 33. ciprocal link means connected to said wiper means, a sec
The slider link 30 enables the rocker arm 16 to drive 70 ond reciprocal link means for driving a second wiper
the reciprocal link 14 in an elliptical path similar to that means, said second reciprocal link means connected to said
described in regards to the embodiment shown in FIG second wiper means, a driving means for driving said ?rst
URI-E 1. Following the initially slow acceleration or and second reciprocal link means, said driving means con
dwell the reciprocal link 13 will be accelerated so that nected to said ?rst and second reciprocal link means, said
the wiper means 3, driven by the reciprocal link 13, will 75 driving means comprising, a motor having a reciprocating
 3,125,777
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action, a means for driving one end of said ?rst reciprocalwiper means so that the overlapping blade portions do not
link means in an elliptical path, said means attached to interfere.
said ?rst reciprocal link means and to said motor, and a 5. The structure de?ned by claim 2 wherein said motor
means for driving one end of said second reciprocal link is placed between said two shafts.
means in a circular path, said means attached to said sec 6. The structure de?ned by claim 2 wherein said ?rst
ond reciprocal link means and to said motor. variable acceleration link has one end slidably mounted
4. In a windshield Wiper, the combination of at least on a portion of the automobile body structure and the
two pivoted wiper means attached to be moved over the other end connected to said second rocker link and said
windshield to clean areas thereof, said wiper means hav reciprocal link is connected to said variable acceleration
ing overlapping blade portions, a ?rst reciprocal link 10 link between the ends of said variable acceleration link.
means for driving a ?rst wiper means, said ?rst reciprocal 7. The structure de?ned by claim 2 wherein a second
link means connected to said ?rst wiper means, a second variable acceleration link is connected to one end of said
reciprocal link means for driving a second wiper means, ?rst variable acceleration link and mounted on a portion
said second reciprocal link means connected to said sec of the automobile body structure, and said reciprocal link
ond wiper means, a driving means for driving said ?rst and is connected between the ends of said ?rst variable accel
second reciprocal link means, said driving means compris eration link.
ing, a motor having a reciprocating action, a ?rst means References Cited in the ?le of this patent
for driving one end of said ?rst reciprocal link means in UNITED STATES PATENTS
an elliptical path, said means attached to said ?rst recipro 2,059,354 Hueber et a1. __________ __ Nov. 3, 1936
cal link means and to said motor, a second means for 2,976,555 Bartoo ______________ __ Mar. 28, 1961
driving one end of said second reciprocal link means in
a circular path, said means attached to said second recip FOREIGN PATENTS
rocal link means and to said motor, whereby said ?rst and 853,835 Great Britain __________ __ Nov. 9, 1960
second reciprocal link means drive said ?rst and second 25 856,338 Great Britain _________ __ Dec. 14, 1960