Breakaway accessory mounting assembly for vehicles and windshield mounted button therefor

A breakaway mounting assembly supports a rearview mirror or other accessory on an improved windshield mounted button. The mounting assembly includes a base having a mount for the accessory or mirror, and a plurality of resilient flanges which engage, hold, and center the assembly on the button but flex to release the assembly if impacted from virtually any direction. Preferably, the resilient flanges are formed in one piece with a retainer mounted on the base by a plurality of mounting flanges also formed in one piece with the retainer and engaging a shoulder on the base. An open release space is defined between a pair of the flanges, while the base has an unobstructed open area aligned with the release space through which the button may be released when the mirror or accessory is impacted directly from the mirror reflecting surface. An inclined wall surface on the base cams the assembly off the button when the mirror or accessory is impacted from the side. The button is tapered toward a curved top end and the windshield attachment surface and has a recess at its bottom end adapted to receive one of the resilient flanges.

BACKGROUND OF THE INVENTION 
This invention relates to support assemblies for mounting accessories such 
as rearview mirrors in vehicles, and more particularly, to a vehicular 
accessory mounting assembly and a windshield mounted button therefor 
adapted for attachment to the inside surface of a vehicle windshield. The 
assembly separates from the button on the windshield if impacted such as 
by an occupant of the vehicle in an accident, or by the expansion of a 
supplemental restraint system or airbag in the vehicle, or by other 
objects. 
Rearview mirrors and other vehicle interior accessories used by the driver 
or other vehicle occupants are commonly secured directly to the inside 
surface of the windshield in the forward vision area of the driver. During 
accidents or sudden stops, if the driver or front seat occupants are 
thrown forwardly, serious injury could result from striking the rearview 
mirror or other accessory or its support system. Thus, many different 
supports have been used in the past to allow the rearview mirror or 
accessory to release and separate from its mounting upon impact. 
More recently, supplemental restraint systems, commonly known as airbags, 
have been incorporated into the instrument panel area or steering wheel 
hub of many vehicles. Such systems include bags which are rapidly inflated 
with pressurized air or gas in a fraction of a second to provide a cushion 
preventing serious injury to the front seat occupants. However, the use of 
airbags has created problems with windshield mounted interior rearview 
mirrors and other accessories. For example, during inflation, an airbag 
can strike the rearview mirror when mounted adjacent the interior 
windshield surface and either tear the bag and destroy its effectiveness 
or actually break the rearview mirror from its mount due to the force of 
the inflation, thereby leaving sharp objects protruding from the broken 
assembly which themselves can injure passengers. 
Alternately, once inflated, a pair of airbags in the front of the vehicle 
can engage one another in the center of the vehicle causing a front seat 
occupant to be funneled toward the boundary therebetween and directly into 
the rearview mirror. Further, inflated airbags can sometimes trap the 
mirror and prevent the mirror from properly releasing to prevent injuries. 
Some prior known accessory/rearview mirror mounts have inadequately 
functioned with inflatable restraint systems and/or may pose potential 
hazards within the vehicle passenger compartment. 
In addition to the above problems, prior known breakaway, windshield 
mounted rearview mirror or other accessory mounting systems have typically 
been designed to accommodate only the governmental regulations and 
customer requirements of a single country or region. For example, United 
States Federal Motor Vehicle Safety Standard 111, European Economic 
Community (EEC) Regulation 72-245/EEC, Japanese Safety Standard Article 44 
and airbag interaction requirements from major United States vehicle 
manufacturers all present differing requirements. Conventional breakaway 
mounting systems have typically failed to accommodate all such regulations 
and requirements thereby requiring different systems and increased costs 
for the mounting of rearview mirrors or other accessories in vehicles 
intended for use in different countries. 
Similarly, different support systems for interior rearview mirrors or 
accessories have been widely used on different vehicles such as a rigid 
arm terminating in a single ball adjustment system or a double ball 
adjustment system. Currently, most single ball adjustment systems, but 
only some of the two ball systems, are designed for breakaway upon impact. 
No previous rearview mirror or accessory mounting system has been 
commercially available to meet all the regulations and requirements of all 
countries and manufacturers with both one or two ball adjustment systems. 
A further problem encountered with conventional mounting systems is the 
lack of stable support causing vibration problems and consequent poor 
vision quality in the rearview mirror when mounted with such systems. 
Moreover, prior known systems have been subject to only partial 
installation by the assembly line worker or other installer. For example, 
in some systems, the mounting attachment can be slid into a partially 
attached position but inadvertently not finally locked in place leaving 
the supported mirror loose and susceptible to severe vibration or even 
allowing the accessory or mirror to drop off the windshield mount early in 
the life of the vehicle. Also, some prior known systems have relied on an 
audible click to indicate to the installer proper mounting onto the 
windshield mount. Such audible clicks may be difficult to hear on an 
vehicle assembly line, may be confused with other noises, or may be 
inaudible to the hearing impaired such as the deaf. 
Another problem is the inability of many prior known systems to allow 
breakaway or release when impacted from virtually any direction. As can be 
appreciated, impact during a collision or sudden stop or deployment of an 
airbag can occur from either the front or rear of the supported mirror, 
from either side, or at various angles in between. Mounting systems which 
fail to release from all directions thereby continue the potential hazards 
and problems noted above and are inadequate to meet the necessary 
worldwide vehicle regulations and customer requirements. 
The present mounting assembly provides an economical, easily manufactured, 
highly reliable system which overcomes these and related rearview mirror 
or other accessory mounting problems in vehicles. 
SUMMARY OF THE INVENTION 
Accordingly, the present invention provides a breakaway accessory mounting 
assembly for vehicles which meets worldwide governmental regulations and 
vehicle manufacturer requirements and, as such, is a universal mount, 
accommodates both one ball and two ball adjustment mounting systems, 
provides release upon impact against the supported mirror or accessory or 
support system from virtually all directions, reduces occupant injuries if 
impacted, avoids damage or hindrance to the operation of supplemental 
restraint systems or airbags in vehicles, provides tactile feedback of 
proper installation on the windshield mounting button, provides stable 
support reducing vibration in the supported mirror or accessory, and 
prevents partial engagement problems causing poor quality visibility in or 
loss of the supported mirror, all while providing a more easily 
manufactured and economical assembly. 
In one form, the invention is a windshield supported, mounting assembly for 
vehicle accessories such as rearview mirrors adapted for breakaway release 
when the rearview mirror or accessory is impacted in a collision by a 
vehicle occupant and/or by a deploying airbag, the assembly comprising a 
base having a body for connecting the assembly to a windshield mounted 
button, a button support on the body, and an accessory/support mount 
providing a connection for the base to at least one of an accessory such 
as a rearview mirror and a support for an accessory such as a rearview 
mirror. The base has a plurality of resilient retaining flanges formed 
from resilient material and located at positions spaced from one another 
around the button support for engaging the windshield mounted button to 
generally center the button therebetween and releasably hold the button 
therebetween and against the button support yet resiliently flex to 
release the button when the rearview mirror or accessory is impacted. A 
pair of the resilient flanges define an open release space therebetween 
allowing release of the button therebetween when the pair of resilient 
flanges are flexed by an impact force which acts on the assembly to urge 
the assembly in a direction such that the button is moved through the open 
release space. The base includes an unobstructed open area aligned with 
the release space between the resilient flanges, the assembly providing an 
open, unobstructed passageway between the open release space and the 
unobstructed open area allowing release of the button from the assembly 
through the open area when the button is caused to move between the pair 
of resilient flanges. 
In a preferred form of the invention, the retaining flanges are spaced in a 
triangular configuration around the button support, and include a pair of 
resilient retaining flanges spaced from one another and the button support 
on opposite sides of the button support and having button engaging 
surfaces extending at an acute angle to one another and adapted to engage 
generally opposed portions of the button. A third, resilient end flange is 
spaced from the pair of retaining flanges and the button support surface 
and is adapted to engage a recess in an end surface of the button in 
opposition to the generally opposed button portions engaged by the 
retaining flanges. 
In other preferred aspects of the invention, the body of the base includes 
a retainer receiving portion which receives and mounts a retainer for 
connecting the assembly to the button. A one-piece retainer is formed from 
resilient material and includes the retainer receiving portion and the 
plurality of resilient retaining flanges. The retainer receiving portion 
may include a retainer recess in the body and an upstanding wall extending 
partially therearound and ending at the open area. The wall preferably 
includes an inclined surface which is adapted to engage the edge of the 
windshield button to help release the assembly from the button when the 
mirror or accessory is impacted from the side. The wall also has a 
shoulder while the retainer preferably also includes a plurality of 
upstanding, resilient mounting flanges, each mounting flange having a 
terminal end. The terminal ends of those mounting flanges engage the 
shoulder on the wall to secure the retainer in the retainer recess. In 
addition, the retainer mounting portion preferably includes an aperture 
receiving the button support with an interference fit to help secure the 
retainer on the retainer receiving portion and to properly orient the 
retainer when assembled to the base. 
Further, the body may include second and third button supports spaced from 
the first mentioned button support and positioned adjacent the end flange 
for providing a three point support on the mounting surface of the button 
when the assembly is mounted on the button. 
Preferably, the pair of resilient flanges and end flange exert forces on 
the button generally parallel to the plane of the windshield surface when 
the assembly is mounted on the vehicle, the windshield surface being 
generally parallel to the button support surfaces on the base member. The 
forces exerted by the flanges act to both center the button within the 
flanges for stable support and hold the entire assembly to the button 
until an impact force causing release is experienced. 
In another aspect, the invention includes a mount or button for attachment 
to a surface of a windshield to support a mounting assembly and an 
accessory such as a rearview mirror. The button includes an attachment 
surface for attachment to a windshield surface, a mounting surface for 
engaging an accessory mounting assembly, and a peripheral edge extending 
between the attachment and mounting surfaces. The peripheral edge defines 
a top end, bottom end and opposing sides. The sides converge toward one 
another in the direction of said top end and taper inwardly toward one 
another from the mounting surface to the attachment surface. The 
peripheral edge at the top end is curved and inclined inwardly from the 
mounting surface to the attaching surface, while the bottom end includes a 
bottom recess spaced toward said attachment surface from the mounting 
surface and has an inner surface and a recess shoulder extending between 
the inner surface and the bottom end. 
The present breakaway accessory mounting assembly and windshield mounted 
button provide numerous advantages over prior known assemblies and 
buttons. First, the mounting assembly is designed to meet current 
governmental regulations and vehicle manufacturer requirements on a 
worldwide basis and can be used with both single ball and double ball 
adjustment systems such that the assembly is a universal system. The 
assembly provides for breakaway release of the supported mirror or 
accessory and any support system due to impact from virtually any 
direction by a vehicle occupant, a deployed airbag within the vehicle 
passenger compartment, or other objects which may strike the mirror. The 
assembly provides a stable support reducing vibration and providing a 
proper platform for mirror adjustment during use while simultaneously 
eliminating partial engagement problems previously experienced upon 
installation of prior known systems which can cause both significant 
vibration and consequent poor quality vision in the supported mirror. The 
assembly may be easily installed without the requirement of tools, 
provides positive tactile feedback indicating complete attachment, and yet 
is easy to remove for repair or replacement of the windshield. In 
addition, the assembly has a reduced number of parts, is economical, and 
is more easily assembled without the requirement of separate fasteners or 
processes than are prior known systems. Further, the windshield mounted 
button is adapted for support of the accessory mounting assembly of the 
present invention, yet accepts many prior known mounting assemblies 
currently in use such that existing accessory supports and mirrors may 
still be used with the button of this invention. 
These and other objects, advantages, purposes and features of the invention 
will become more apparent from a study of the following description taken 
in conjunction with the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to the drawings in greater detail, FIGS. 1, 2 and 13-20 
illustrate a first embodiment 10 of the breakaway accessory mounting 
assembly of the present invention. Breakaway accessory mounting assembly 
10 is shown secured to an improved, double-tapered, wedge-type, windshield 
mounted button 12 adapted to be secured to the inside surface of a vehicle 
windshield which is typically formed from laminated safety glass, as shown 
in FIGS. 15-20. The breakaway accessory mounting assembly 10 includes a 
base member 14 receiving a one-piece, resilient retainer 16 mounted 
thereon, the retainer adapted to engage and retain the entire assembly to 
button 12 when the button is secured to a windshield. As explained below, 
base 14 includes an outwardly extending ball member 82 adapted to 
adjustably receive either an interior rearview mirror assembly 26 directly 
or an adjustable support assembly, such as the two-ball support assembly 
18 shown in FIG. 1. Adjustable support assembly 18 is of conventional 
design and includes a tube 20 having ball cup members 22 received in the 
ends of the tube and urged outwardly toward the ends by an intermediate 
coil spring 24, all as more fully described in U.S. Pat. No. 5,377,949, 
assigned to the same assignee as the present invention, the disclosure of 
which is hereby incorporated by reference herein. The second ball member 
25 received in the outer end of the tube of support assembly 18 projects 
from interior rearview mirror assembly 26 and forms no part of the present 
invention. Mirror assembly 26 has a rearwardly facing reflecting surface 
27. As described below in connection with FIG. 21, a second embodiment 150 
of the breakaway accessory mounting assembly may incorporate a rearview 
mirror or accessory support arm 152 extending from the base member 14' and 
supporting a single ball-type adjustment member 154 for attachment 
directly to an interior rearview mirror assembly (not shown). Both 
embodiments of the breakaway accessory mounting assemblies 10, 150 
incorporate substantially the same base and retainer and are adapted to 
releasably attach to the same improved windshield mounted button 12. As 
referenced in the following description, rearview mirror assembly 26 and 
support arm 18 or adjustment member 154 extend rearwardly into the 
passenger compartment of the vehicle from the windshield area. Mounting 
assembly 10, 150 is typically positioned centrally on the windshield above 
the vehicle instrument panel. The direction to the left and toward the 
windshield in FIG. 1 is, therefore, the forward direction, while that to 
the right and toward the passenger compartment is the rearward direction. 
As will be understood, breakaway accessory mounting assembly 10, 150 could 
be mounted on other windows or other vehicle panels to support other 
accessories, such as compasses, interior lights, cellular telephones or 
microphones, radar detectors, or other vehicle accessories, all of which 
may require release upon impact during an accident, airbag deployment, or 
the like. 
As is best seen in FIGS. 3-5, the improved windshield mounted button 12 is 
a preferably generally planar, elongated body formed from sintered 
stainless steel although other metals, plastics and forming processes 
could also be used. Button 12 is preferably adhered to the surface of a 
glass windshield W (FIGS. 15-20) by a layer of conventionally known metal 
to glass adhesive, such as polyvinylbuteral available from Monsanto 
Company of St. Louis, Mo., silicone available from Dow Corning Corporation 
of Midland, Mich., or modified epoxy tape available from 3M Company of St. 
Paul, Minn. The button includes a generally planar, forward facing 
attachment surface 30 adapted to be adhered to the inside surface of the 
windshield, a generally planar, rearward facing mounting surface 32 for 
engaging the breakaway accessory mounting assembly 10 on the side of the 
button opposite attachment surface 30, a curved top end 34 and a generally 
planar bottom end 36. Bottom end 36 extends generally perpendicular to 
surfaces 30, 32. Extending between the attachment and mounting surfaces 
30, 32 is a peripheral edge including inwardly converging or angled side 
edges 38, 40 which taper inwardly from the larger mounting surface 32 
toward the smaller attachment surface 30, and a curved edge 42 which 
extends from one side edge 38 to the other side edge 40 and along the 
curved top end 34. Edge 42 is angled inwardly for its full extent in the 
same manner as side edges 38, 40 as shown in FIG. 4. In addition, side 
edges 38, 40 converge toward one another as they extend toward top end 34 
thereby providing the button 12 with an overall double tapered shape. The 
corner between surface 32 and edge surfaces 38, 40, 42 is radiused and 
rounded as shown at 35 (FIGS. 4, 5 and 17) to meet the requirements for 
interior vehicle parts which could be exposed and struck in an accident 
such as in the EEC. Rounded corner 35 also cooperates with inclined 
surface 65 on wall 62 to allow release of the assembly when mirror 26 is 
impacted from the side as is more fully explained below. In addition, 
bottom end 36 includes a notch or recess 44 having a bottom or floor 46 
which is generally planar and parallel to end surface 36, and an inwardly 
angled surface or shoulder 48 extending between end surface 36 and floor 
46 parallel to mounting surface 32. Recess 44 is spaced from mounting 
surface 32 toward attachment surface 30 and opens to attachment surface 
30. As explained below, shoulder 48 provides an inclined contact surface 
for a resilient retaining flange on bracket 16 when assembly 10 is mounted 
on button 12. Button 12 also includes a corner or edge 37 between mounting 
surface 32 and bottom end 36 which is radiused or rounded like corner 35 
above to meet EEC vehicle regulations and to aid in the flexing of end 
flange 94 into recess 44 as explained below. Corner 37 enables button 12 
to be used with other prior known mounting assemblies in addition to 
assemblies 10, 150 described herein. As shown in phantom in FIG. 3, button 
12 may also include ribs or ridges 45 which enable the button to be used 
with mounting assemblies such as those in U.S. Pat. Nos. 4,936,533 and 
5,100,095. Optionally, attachment surface 30 of button 12 may be secured 
by sintering or brazing to a stainless steel or zinc plate having an area 
larger than that of attachment surface 30 to provide an enlarged area for 
increased adherence to the windshield surface via adhesives such as those 
mentioned above. 
With reference to FIGS. 2, 6-8, 13 and 14, base member 14 is preferably die 
cast from zinc or another suitable metal or, alternately, can be molded 
from resinous plastic material. Suitable resinous plastic materials 
include VERTON.TM., a long fiber, glass-filled nylon available from LNP 
Engineering Plastics Inc. of Exton, Pa., GRIVORY GV.TM., a short glass 
fiber-filled nylon available from EMS American Grilon Inc., Sumter, S.C., 
TERLURAN.TM., an acrylonitrile butadiene styrene (ABS) polymer available 
from BASF Corporation of Parsippany, New Jersey, or other high modulus, 
low creep, engineering plastics, such as polybutylene terephthalate (PBT) 
or polyethylene terephthalate (PET). Base 14 includes a body 50 including 
a generally planar, rectangularly-shaped, retainer receiving portion or 
area 52 having a top end 54, opposing side edges 56, 58, a bottom end 60, 
and an upstanding wall 62. Wall 62 includes a terminal surface 63, side 
portions 62a, 62b and bottom end portion 62c which extend continuously 
along and around side edges 56, 58 and bottom end 60 of the bracket 
receiving area 52 to define a recess or receptacle in which retainer 16 is 
received and secured. The inside surfaces of side portions 62a, 62b of 
wall 62 include inwardly extending lips 64 defining an undercut shoulder 
for securing retainer 16, as well as outwardly inclined surfaces 65 (FIGS. 
2, 6, 8, 13, 14 and 17) which engage radiused corners 35 on button 12 when 
mirror 26 or a supported accessory is impacted from the side causing 
assembly 10, and thus the supported mirror to be cammed off and released 
from button 12. In addition, opposed rectangular openings 66a, 66b provide 
clearance room for flexing of portions of retainer 16 to release from 
button 12, while a tool receiving opening 68 is formed in bottom end wall 
62c for receipt of a small screwdriver or other tool to allow removal of 
the assembly from button 12 when desired. Also formed within the recess or 
receptacle of the retainer receiving portion 52 are a series of button 
supports 70, 72a, and 72b. Button support 70 is a free-standing, 
triangularly-shaped post having sides 71a, 71b, 71c (FIG. 6) and a 
generally planar top surface 74 which is spaced slightly below the 
terminal edge of wall 62 (FIGS. 15-17 and 20). Button supports 72a, 72b 
include generally planar top surfaces 76a, 76b which are generally 
co-planar with surface 74 of button support 70. Button supports 72a, 72b 
are integrally formed with the interior surface of wall 62 adjacent the 
corners between side wall portion 62a, 62b and bottom wall portion 60, 
respectively. Button supports 70, 72a, and 72b are positioned in a 
triangular configuration with support 70 being generally equidistant from 
wall portion 62a, 62b and spaced toward top edge 54 from bottom wall 
portion 62c. Button supports 72a, 72b are adjacent but spaced from end 
flange 94 of retainer 16 when the retainer is mounted on base 14. An 
inclined surface 78 is formed between retainer receiving surface 52 and 
bottom wall portion 62c (FIGS. 2, 6 and 13) to provide a support for one 
of the retaining flanges of retainer 16 as explained more fully below. 
In addition, body 50 of base member 14 includes a downwardly extending 
contoured section 80 projecting below retainer receiving surface 52 from 
which ball member 82 extends at an acute angle to the plane of surface 52 
on neck portion 84. As shown in FIGS. 2, 6, 8, 13 and 14, wall portions 
62a, 62b end adjacent top edge 54 of retainer receiving surface 52 to 
define an unobstructed open area 55 (FIGS. 6, 14) which is aligned with 
the apex 73 defined by inwardly converging sides 71a, 71b of triangular 
button support 70. Like surface 74 of button support 70, surfaces 76a, 76b 
of button support 72a, 72b are spaced slightly below the terminal edge of 
wall 62. 
As is best seen in FIGS. 2, 9-12, and 13-17, button receiving retainer 16 
is a one-piece member preferably stamped from resilient, spring steel and 
having a thickness preferably within the range of between about 0.030 and 
0.040 inches, and preferably about 0.035 inches. Retainer 16 includes a 
generally planar mounting area 90 from which extend a plurality of 
outwardly extending, cantilever-type, button retaining and end flanges 
92a, 92b, and 94, and a plurality of retainer mounting flanges 96a, 96b 
and 98a, 98b. A securing aperture 100 is configured in a triangular shape 
defined by an upturned lip 102 to correspond to the shape and size of 
button support 70 on base 14 to provide an interference fit when placed 
thereover. Mounting flanges 96a, 96b and 98a, 98b are outwardly flared and 
terminate in generally co-planar end surfaces 104a, 104b and 106a, 106b 
which face outwardly and upwardly and are adapted to nest under the 
retaining shoulder defined by lip 64 on the interior surface of upstanding 
wall 62 on base 14 when the retainer is received in the retainer receiving 
recess of the base against surface 52. Mounting portion 90 includes an 
elongated, indented rib 91 to provide additional strength resisting 
flexing of the mounting portion from which mounting flanges 96a, 96b 
extend. 
As is best seen in FIGS. 9-12, top edge 108 of retainer 16 defines one edge 
of mounting flanges 96a, 96b while bottom edge 110 defines one side of 
mounting flanges 98a, 98b. End flange 94 extends upwardly from an 
intermediate flange 112 which projects outwardly at an inclined angle from 
the bottom edge 110 of retainer 16. End flange 94 is bent to include a 
rectilinear rib or ridge 114 facing aperture 100 and defined by an 
inwardly bent, V-shaped portion 116 at its outer terminal end. Retaining 
flanges 92a, 92b each extend outwardly at an angle to the longitudinal 
axis A of retainer 16 (FIG. 9) and are separated from mounting flanges 
96a, 96b and 98a, 98b by slots 118 and V-shaped recesses 120, 
respectively. Each retaining flange 92a, 92b is outwardly curved having a 
convex outer surface and a concave inner surface and terminating in planar 
end surfaces 122a, 122b with sharp rectilinear edges 124a, 124b extending 
between the concave inner surface and the generally planar end surface of 
each flange. Preferably, ends 122a, 122b and edges 124a, 124b extend at an 
angle of between about 25.degree. and 30.degree. to longitudinal axis A, 
most preferably about 27.degree., such that those ends and edges extend at 
an angle to one another of between about 50.degree. and 60.degree., most 
preferably about 54.degree.. As will be understood from FIGS. 2, 9, and 
12-14, retaining flanges 92a, 92b and end flange 94 are spaced from one 
another and positioned in a generally triangular configuration, each being 
generally equidistant from aperture 100 and, thus, triangular button 
support 70 when retainer 16 is mounted in base 14. Retaining flanges 92a, 
92b are spaced from one another to define an open release space 125 (FIGS. 
2, 11, 13, 14, 16, 20 and 21) which allows release of the windshield 
mounted button therebetween when those flanges are flexed by an impact 
force which acts on the breakaway accessory mounting assembly 10 to urge 
the assembly in a direction such that the button passes through that open 
release space as will be more fully explained below. 
The assembly of retainer 16 with base 14 is now best understood from FIGS. 
2, 13 and 15-17. Retainer 16 is generally positioned parallel to retainer 
receiving surface 52 of body 50 of base 14 with the mounting and retaining 
flanges extending outwardly away from surface 52. Aperture 100 is aligned 
with triangular button support 70 and retainer 16 and base 14 are moved 
together such that aperture 100 telescopes over button support 70. 
Movement of the two parts together is continued until the outer surfaces 
of mounting flanges 96a, 96b, 98a, 98b engage the inwardly angled surfaces 
of wall portions 62a, 62b. Continued movement with pressure forces 
retainer 16 into the recess defined by wall 62 with mounting flanges 96a, 
96b and 98a, 98b being flexed inwardly. As the terminal end surfaces 104a, 
104b and 106a, 106b pass the edge of lip 64, the resiliency of the 
retainer material urges the mounting flanges outwardly such that the 
terminal ends engage the undersurface of the retaining shoulder defined by 
lip 64. At the same time, the interference fit between the rounded, 
upwardly extending lip 102 of aperture 100 and the side surfaces of button 
support 70 tightly engage one another. Hence, retainer 16 is permanently 
mounted within the recess defined by wall 62 and against button receiving 
surface 52 by the combined action of the mounting flanges 96a, 96b and 
98a, 98b and lip 64 as well as the interference fit between the edge 102 
of aperture 100 and the sides of button support 70. No other fasteners or 
attachment processes are necessary. 
As shown in FIGS. 13 and 15-17, when retainer 16 and base 14 are assembled 
in this manner, the terminal ends 122a, 122b and 116 of retaining flanges 
92a, 92b and end flange 94 project outwardly beyond the terminal surface 
of wall 62. At the same time, button support surfaces 74, 76a, 76b are 
positioned slightly below the terminal surface of wall 62 and intermediate 
retainer receiving surface 52 and the terminal ends of the retaining and 
end flanges. In addition, intermediate flange 112 from which end flange 94 
extends engages and rests on inclined surface 78 to provide support for 
that end flange and to allow flexing at the bend between flange 94 and 
intermediate flange 112. In addition, a clearance space is provided 
between end flange 94 and the interior surface of bottom wall 62c (FIG. 
15), while openings 66a, 66b provide clearance space for the outward 
flexing of retaining flanges 92a, 92b to allow release of the button 12 
from assembly 10. In the event base 14 is provided with a wider retainer 
receiving surface 52 such that larger spaces are provided between 
retaining flanges 92a, 92b and walls 62a, 62b, openings 66a, 66b may be 
eliminated so that walls 62a, 62b are continuous and uninterrupted. 
Further, bottom edge 110 of retainer 16 engages the upper side surfaces of 
button supports 72a, 72b to help position retainer 16 in base 14 and 
prevent its shifting. The triangular configuration of button support 70 
and aperture 100 are provided to insure proper orientation of bracket 16 
on base 14 and to prevent their assembly in any orientation other than 
that as described above. In addition, the orientation of triangular button 
support 70 with apex 73 pointing toward release space 125 between 
retaining flanges 92a, 92b positions the widest portion of the button 
support surface 74 as close as possible to end flange 94 and support 
surfaces 76a, 76b. In addition, when assembled in this manner, space 125, 
which is aligned with apex 73 of button support 70 and end flange 94, is 
also aligned with the unobstructed open area 55 in base 14 between the 
upper ends of wall portion 62a, 62b adjacent upper edge 54. As will be 
understood from FIGS. 13, 14, space 125 of bracket 16 and open area 55 of 
base 14 define an unobstructed, open passageway which allows button 12 to 
pass therethrough when a sufficient impact force is received on assembly 
10, 150 along axis A through ball member 82 and body 50 (FIG. 9) such that 
flanges 92a, 92b are flexed toward openings 66a, 66b and button surface 32 
slides along button support surfaces 74, 76a and 76b. 
As noted above, if base 14 is molded or otherwise formed in one piece, it 
may include retaining flanges 92a, 92b and end flange 94 molded to be 
resilient and in one piece with base 14 so as to extend and project 
outwardly from retainer area 52 without the need for a separately formed 
and attached retainer 16. The positions and spacing of such flanges with 
respect to walls 60, 62, button supports 70, 76 and openings 66a, 66b and 
56 and the other feature of base 14 would be substantially similar to that 
when retainer 16 is mounted on base 14 as described above. 
With reference to FIGS. 14-20, the installation and mounting of breakaway 
accessory mounting assembly 10 on windshield supported button 12 will now 
be understood. Assembly 10, with accessory support arm 18 mounted on ball 
member 82 and supporting a rearview mirror 26 or other accessory at the 
free end thereof, is oriented with ball member 82 extending upwardly 
toward the top of the windshield and body 50 of base 14 angled outwardly 
away from the inside surface of windshield W as shown in FIG. 18. 
Rectilinear edges 124a, 124b of retaining flanges 92a, 92b are hooked over 
and engaged with generally opposed portions of inwardly angled, curved 
peripheral edge 42 at the curved top end 34 of button 12 without any 
sliding action. In such position, terminal end 116 of end flange 94 may be 
slightly spaced from or touching radiused edge 37 of button 12 extending 
between surface 32 and end surface 36. The entire assembly is then rotated 
toward windshield W while retaining flanges 92a, 92b and specifically 
sharp, rectilinear edges 124a, 124b, remain in contact with peripheral 
edge portion 42 of button 12 such that the inclined surface of terminal 
end 116 is forced against edge 37 of button 12 causing flange 94 to flex 
outwardly at the bend between intermediate flange 112 and end flange 94. 
The clearance space between end flange 94 and the inner surface of end 
wall portion 62a allows such flexure while continued rotation forces ridge 
114 over rounded edge 37, along the end surface 36 and into recess 44 
where ridge 114 engages and rests against the inclined surface of shoulder 
48 of recess 44 (FIGS. 15 and 19). In such position, end flange 94 is 
flexed toward bottom wall portion 62c slightly to create a retaining force 
generally parallel to surfaces 30, 32 of button 12, button support 
surfaces 74, 76a, 76b, and the inside surface of windshield W which urges 
button 12 to the left in FIG. 15, against retaining flanges 92a, 92b, and 
toward release space 125 between flanges 92a, 92b. Simultaneously, 
retaining flanges 92a, 92b are slightly flexed outwardly by the engagement 
of edges 124a, 124b with surface 42 to create opposing retaining forces 
acting both inwardly toward button support 70 and toward end flange 94 and 
urging button 12 to the left in FIG. 15. Like the force from end flange 
94, the forces from retaining flanges 92a, 92b on button 12 act in a 
direction generally parallel to surfaces 30, 32 of button 12, button 
support surfaces 74, 76a, 76b, and the inside surface of windshield W. As 
a consequence, assembly 10 is generally centered over button support 70 on 
surface 74 with the lower corner areas of mounting surface 32 of button 12 
engaging the support surfaces 76a, 76b of button supports 72a, 72b to 
provide a stable, three-point support of the button on base 14. 
Simultaneously, the inwardly angled surfaces 42 and shoulder 48 cause 
retention of assembly 10 on button 12 and urge assembly 10 toward 
windshield W since the resiliency of flanges 92a, 92b and end flange 94 
thus simultaneously create forces acting generally perpendicular to those 
inclined surfaces which pull assembly 10 toward button 12. Accordingly, 
button 12 is generally centered between retaining flanges 92a, 92b and end 
flange 94 while being held therebetween and urged toward button 12 and 
windshield W in its mounted position. 
When ridge 114 of end flange 94 snaps into recess 44 and against shoulder 
48, the installer can feel the snapping action as mounting surface 32 
engages against button support surfaces 70, 76a, and 76b. This action 
provides a tactile feeling and feedback which confirms proper mounting of 
assembly 10 on button 12 to the installer. In addition, unless flanges 
92a, 92b are properly engaged with surface 42 and end flange 94 is 
properly engaged with ridge 114 in recess 44 and against shoulder 48, the 
entire assembly, including support arm 18 and mirror 26 or other 
accessory, will not be retained on the button and will fall away from 
button 12 when the installer's hand is released from the assembly. The 
engagement of edges 124a, 124b with surface 42 without the retaining 
action of end flange 94 in recess 44 will allow the entire assembly to 
rotate in one direction or the other around the curved surface of button 
12 causing the entire assembly to fall from the button unless ridge 114 is 
properly seated in recess 44. Accordingly, partial engagement, which can 
lead to severe vibration or dropping of the assembly from the button some 
time after installation is attempted, is prevented with the present 
invention. In addition, proper installation provides stable, three-point 
support of the base 50 against mounting surface 32 of button 12 while the 
retaining and end flanges tightly hold the assembly to the mounting 
button. This prevents vibration which would otherwise be transmitted 
through support arm to the rearview mirror causing reduced quality vision 
in the mirror while also providing stable support which allows grasping of 
the mirror or support arm for adjustment purposes without causing shifting 
of the assembly 10 on the button or otherwise disturbing its properly 
mounted position. 
As will also be understood from FIGS. 13-17 and 20, when the mirror or 
other supported accessory is impacted by an occupant of the vehicle, an 
airbag during deployment or another object within the vehicle passenger 
compartment, assembly 10 will be released from button 12 without fracture 
or creation of sharp edges due to the flexure of retaining flanges 92a, 
92b and end flange 94 regardless of the direction from which the impact 
force acts on the overall assembly. Importantly, bracket 10 will be 
released from button 12 when a force acts through the rearwardly facing 
reflective surface 27 of mirror 26, support arm 18, ball member 82 in the 
direction of arrow B in FIG. 15 aligned with axis A and open area 55 of 
base 14, and release space 125 between the retaining flanges 92a, 92b and 
button support 70 and end flange 94. When an impact force engages the 
mirror or support arm in such direction, a force is created urging button 
12 against retaining flanges 92a, 92b such that the tapered shape of 
button 12 wedges the retaining flanges apart causing them to flex toward 
openings 66a, 66b or walls 62a, 62b and allowing the button to slide in a 
direction generally parallel to support surfaces 74, 76a and 76b and the 
windshield surface through release space 125 between the retaining 
flanges. If the impact force is of sufficient size, the button will be 
forced entirely through and between flanges 92a, 92b in a direction 
parallel to the plane of the support surfaces and on through the 
unobstructed open area in base 14 and the passageway defined by space 125 
and open area 55, between the ends of wall portions 62a, 62b and away from 
end flange 94 such that the entire assembly 10 will move downwardly off 
button 12 toward the instrument panel and/or floor of the vehicle out of 
harms way. 
Likewise, should assembly 10 be struck from under ball member 82 in the 
direction of arrow C in FIG. 15, end flange 94 will be flexed outwardly in 
the reverse of the installation procedure also allowing the assembly to 
fall from the button after ridge 114 moves out of recess 44. Further, 
impact from the sides of the mirror and support arm on assembly 10 and 
toward one of the inclined wall surfaces 65 will cause flexure of one or 
the other of retaining flanges 92a, 92b and/or end flange 94, allowing one 
of the rounded corners 35 to engage one of the inclined wall surfaces 65 
such that the base 14 and thus assembly 10 will be cammed away from button 
12 and windshield W, again allowing release of the assembly from the 
button 12. The same occurs if impact forces are directed at oblique angles 
to the side or end surfaces of the assembly since one or more of the 
retaining and/or end flanges will flex and segments of corners 35 and 
inclined wall surfaces 65 will engaged one another to allow release of the 
assembly in reaction to such forces. Accordingly, release of the assembly 
when impacted by forces acting in virtually any direction on the mirror or 
support arm when supported by assembly 10 on button 12 is provided for 
with the present invention. 
As shown in FIG. 21, a second embodiment 150 of the breakaway accessory 
mounting assembly of the present invention is shown where like numerals 
indicate like parts to those in embodiment 10. Assembly 150 incorporates 
retainer 16 adapted for engagement with windshield supported button 12 in 
the same manner as described above for embodiment 10. Retainer 16 is 
adapted to be mounted on a base 14', including a retainer receiving 
surface 52', and upstanding wall 62' defining a recess receiving retainer 
16 in the same manner as in embodiment 10, along with button supports 70', 
72a', 72b', inclined surface 78', a retaining shoulder defined by lip 64', 
inclined wall surfaces 65', flexure openings 66a' 66b', and the remaining 
features of body 50 of embodiment 10. In addition, however, base 14' 
includes a downwardly extending, rigid support arm 152 including a 
rearwardly extending projection defining a ball member 154 on neck 156. 
Ball member 154 is adapted to be received in a swivel socket formed in a 
rearview mirror assembly or other accessory to be mounted via assembly 150 
adjacent the inner surface of a windshield in like manner to that 
described above for embodiment 10. Ball member 154 provides a single 
swivel joint for adjusting the position of the mirror or other accessory 
as opposed to the double swivel joint provided by double ball support arm 
18 in embodiment 10. Alternately, ball member 154 in embodiment 50 could 
be a swivel socket at the end of arm 152 in the manner described in U.S. 
patent application Ser. No. 08/336,296, filed Nov. 8, 1994, assigned to 
the same assignee as the present invention, now U.S. Pat. No. 5,615,857, 
the disclosure of which is hereby incorporated by reference herein. 
Accordingly, the present invention is useful with both single ball 
adjustment systems and double ball adjustment systems. 
While several forms of the inventions have been shown and described, other 
forms will now be apparent to those skilled in the art. Therefore, it will 
be understood that the embodiments shown in the drawings and described 
above are merely for illustrative purposes, and are not intended to limit 
the scope of the invention which is defined by the claims which follow 
interpreted under the principles of the patent law including the Doctrine 
of Equivalents.