Abstract:
A modular rearview mirror assembly for vehicles incorporates a housing into the mirror assembly case for supporting an electronic control module to reduce the vibration, to ease the installation of the components in the mirror assembly, and to improve access to the various components in the mirror assembly for maintenance or repair. The rearview mirror assembly includes a reflective element, at least one electrical component mounted to the reflective element, and a case housing the reflective element and the electrical component. An electronic control module is supported by the case which communicates with the electrical component. Preferably, the electronic control module is supported by a housing that is either molded with the case or welded to the inner surface of the case to support the electronic control module independently from the electrical component.

Description:
This application is a continuation-in-part of application Ser. No. 08/316,047 entitled MODULAR VARIABLE REFLECTANCE MIRROR ASSEMBLY and filed on Sep. 30, 1994, now U.S. Pat. No. 5,659,423. 
    
    
     TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     This invention relates to an improved modular exterior rearview mirror assembly incorporating an electronic control module. More particularly, the present invention relates to the mounting of the electronic control module within the exterior rearview mirror assembly housing. 
     Conventional exterior rearview assemblies include a mirror housing, a reflective element supported in the housing by a mirror actuator for engaging the reflective element for adjusting the reflective element&#39;s orientation. Typically, the mirror actuator is controlled either manually by a lever inside the vehicle or electrically by a switch inside the vehicle. In recent developments, mirror assemblies may include mirror actuators responsive to memory devices that store multiple positions for the mirror assembly&#39;s reflective element, such as disclosed in U.S. Pat. No. 5,196,965 to Lang et al. entitled REARVIEW UNIT FOR MOTOR-VEHICLES, which is incorporated by reference herein. Furthermore, mirror assemblies may include: Electro-optic reflective elements, which adjust the reflectance level of the reflective element; remote-actuated exterior vehicle security lights and signal lights, such as disclosed in commonly assigned U.S. Pat. Nos. 5,371,659 and 5,497,305 for REMOTE ACTUATED EXTERIOR VEHICLE SECURITY LIGHT; Global Positioning System antennas or receivers, as disclosed in patent application Ser. No. 08/569,851 filed Dec. 8, 1995, by Roger L. Veldman and Desmond J. Farrell for a VEHICLE GLOBAL POSITIONING SYSTEM NAVIGATION AID; heaters, to remove ice from the reflective element, such as disclosed in U.S. patent application Ser. No. 07/971,676, filed Nov. 4, 1992, by Niall R. Lynam et al. for AN ELECTROCHROMIC MIRROR FOR VEHICLES, now U.S. Pat. No. 5,446,576; and blind spot detection systems, such as disclosed in U.S. patent application Ser. No. 60/013,941 filed Mar. 22, 1996, by Kenneth (NMI) Schofield for PROXIMITY DETECTION OF OBJECTS IN AND AROUND A VEHICLE, the disclosures of which are hereby incorporated herein by reference. Various other devices housed in an exterior mirror assembly include heading sensors, intrusion detectors, variable reflectance control systems for electrochromic mirror operation, transmitting and/or receiving antennas, such as antennas for global positioning systems (GPS) and intelligent vehicle highway systems (IVHS), garage door opener transmitters and antennas, cellular telephone transmitters and antennas, and the like are candidates for positioning within a mirror assembly. For example, an electronically trainable garage door opener may be included, such as is described in U.S. Pat. No. 5,479,155 issued to Zeinstra et al. 
     The increase in electronic functions being performed through the vehicle rearview assembly increasingly involves communication with other portions of the vehicle. For example, global positioning system (GPS) functions and intelligent vehicle highway system (IVHS) functions may interact with other modules controlling vehicle navigation and the like. A headlamp control of the type disclosed in commonly assigned U.S. patent application Ser. No. 08/768,193 for AUTOMATED REARVIEW MIRROR SYSTEM WITH AUTOMATIC HEADLIGHT ACTIVATION, now U.S. Pat. No. 5,715,093, which was a continuation of U.S. patent application Ser. No. 08/277,674 filed Jul. 19, 1994, by Kenneth L. Schierbeek and Niall R. Lynam, for an AUTOMATIC REARVIEW MIRROR SYSTEM WITH AUTOMATIC HEADLIGHT ACTIVATION, now abandoned the disclosure of which is hereby incorporated herein by reference, utilizes common light sensors for activating the vehicle&#39;s headlights and establishing a partial reflectance level for an electro-optic mirror element. Such features may require interaction between the mirror assembly and a headlamp module. 
     The vehicular exterior mirror assembly has become sophisticated resulting in a more complicated assembly having a plurality of electrical components and electronic controls. Frequently, the electrical components and electronic controls are separately installed and, quite often, commonly mounted to the reflective element. This is especially common where an electrical function associated with the reflective element is performed. For example, in U.S. patent application Ser. No. 08/316,047, filed Sep. 30, 1994, by Kenneth L. Schierbeek et al., entitled MODULAR VARIABLE REFLECTANCE MIRROR ASSEMBLY, now U.S. Pat. No. 5,659,423 the disclosure of which is hereby incorporated herein by reference, two generally rearwardly directed light sensors are mounted, along with a mirror reflectance level control circuit to the back of the reflective element. Hence, the overall weight of the mirror assembly is significantly increased but without a corresponding increase in the stiffness to its supporting structure. This may result in a mirror actuator assembly and reflective element with a lower natural frequency, which subjects the mirror actuator assembly to increased vibration. This increased vibration can induce unwanted distortion in the reflected image in the reflective element and may shorten the service life of the various components subjected to the vibration. 
     Furthermore, as the number of components and controls increase the amount of available space within the housing to accomrnodate all these components and controls is becoming increasingly limited. Moreover, since a large number of the components are installed on the back of the mirror actuator assembly, servicing of the mirror actuator assembly is more difficult. Typically each component requires removal in order to access the components within the mirror actuator assembly housing. 
     Accordingly, there is a need for an exterior mirror assembly that is not as susceptible to vibrations. There is also a need for an exterior mirror assembly that provides more space for the many electrical components and electronic controls that are desirable in today&#39;s sophisticated exterior mirror assembly. Moreover, there is a need for a mirror assembly that is easier to assemble and service. 
     SUMMARY OF THE INVENTION 
     The present invention provides an improved modular exterior rearview mirror assembly for vehicles incorporating various electronic controls, including, by way of example, instruments, antennas, sensors, and other accessories, into an electronic control module and mounting the electronic control module remotely from the mirror actuator assembly within the rearview mirror assembly to provide more space in the mirror assembly housing, resulting in a rear view assembly with significantly reduced vibration and improved accessibility to the various components in the mirror assembly. 
     In one aspect, the invention provides a modular exterior rearview mirror assembly for vehicles for mounting on a vehicle, including a case, a reflective element assembly housed in the case and supported by a reflective support means, and an electronic control module mounted in the case independently of the reflective element assembly and the reflective support means. In one aspect of this invention, the reflective element assembly includes an electrical component electrically interconnected with the electronic control module. The electrical component may comprise an electro-optic element, a light sensor module, a heater pad, an ultrasonic transducer, or a mirror actuator assembly. Furthermore, the electronic control module may be supported in a housing. In one aspect, the housing may comprise a molded insert which inserts into the mirror assembly case, a compartment supported on the inner surface of the mirror case, or an enclosure formed by insert molding, potting, or other encapsulating methods. In another aspect, the housing may comprise a compartment supported on the mounting bracket or an enclosure provided on the mounting bracket. 
     According to another aspect of the invention, a mounting bracket, a case, a reflective element assembly, and an electronic control module are all provided as set forth above. The electronic control module may include an antenna, which may include one of a GPS antenna, a cellular phone antenna, and a garage door opener antenna, and the like. 
     According to another aspect of the invention, a vehicular exterior rearview mirror assembly includes a reflective mirror element, an electrical component mounted to the reflective element, a body housing the reflective element, and an electronic control module spaced from the reflective mirror and the electrical component and remotely supported by an inner surface of the body. The electronic control module may be supported in a housing supported by the inner surface of the body. Furthermore, the housing may include a sealing member to seal the housing against the inner surface of the body. In other aspects, the electronic control may include an antenna. The electrical component may comprise an electro-optic cell, a light sensor, or a mirror actuator assembly. 
     According to yet another aspect, the invention includes a case, a reflective element housed in the case, and an electronic control module mounted to the case, wherein the electronic control module includes an antenna. The housing may comprise a modular insert mounted in a wall of the case. Furthermore, the modular insert is adapted to insert into and be supported by an aperture provided in the case and includes an exterior surface which is flush with an exterior surface of the case. 
     According to yet another aspect of the invention, a cellular phone system is provided which includes an exterior mirror assembly having a reflective element, a case for the reflective element, and a cellular phone system receiver and electrical leads coupled to an antenna positioned within the case. The case may include a housing to support the antenna. Furthermore, the housing may be removable. In one aspect of this invention, the case includes an opening and the housing is supported in the opening. Preferably, the housing includes an exterior surface which is flush with an exterior surface of the case. 
     Accordingly, the present invention provides a simplified exterior rearview mirror assembly by incorporating a housing member for supporting an electronic control module, preferably carrying some or all the electrical controls for electrical components supported in the mirror assembly, in a position remote from the reflective element assembly within the mirror assembly case, and in a manner that does not add weight to the reflective element assembly, and thus does not contribute directly to the vibration thereof when operated on a highway. The electronic control module housing member may be adapted to releasably support the electronic control module therein. By supporting the electronic control module remote from the reflective element assembly, the frequency response of the reflective element assembly to vibration associated with road travel is reduced. The electronic control module housing can also be molded in different configurations for each specific type of mirror assembly case so as to mount the electronic control module housing on a different inner surface of the mirror case. 
     This invention makes commercially possible the molding of a one-piece mirror housing which incorporates a support structure for the electronic control module housing in the resinous mirror case to allow quick insertion of an electronic control module. Such one-piece housings are preferably made from polyolefin resins such as polypropylene or polypropylene/polyethylene copolymers having lower heat deflection temperatures, higher material shrinkage rates, and lower cost. 
     The present invention also provides a cellular phone system incorporated into a modular exterior rearview mirror assembly. By locating the cellular phone system antenna in the mirror assembly the antenna is protected from the elements, such as rain, ice, snow, and spray from the road. Moreover, by supporting the antenna on an inner surface of the case, remote from the reflective element assembly, the antenna will be subjected to less vibration, which is commonly exhibited by the reflective element assembly, and will not increase the weight of the reflective element assembly, which may induce further undesirable vibration. Furthermore, the exterior mirror assembly is a convenient location for connecting the antenna to the cellular phone receiver, which is typically located in the vehicle compartment. 
     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. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top plan view of a vehicle incorporating an exterior modular rearview mirror assembly of the present invention; 
     FIG. 2 is a rear elevational view of the exterior modular rearview mirror assembly of FIG. 1; 
     FIG. 3 is a sectional view taken along line III--III of FIG. 2, illustrating the electronic control module housing supported in the mirror assembly; 
     FIG. 4 is the same view as FIG. 3, illustrating the support structures provided on the mirror assembly case for supporting an electronic control module housing, with the electronic control module removed for clarity; 
     FIG. 5. is a plan view of the electronic control module looking along line V--V of FIG. 3; 
     FIG. 6 is the same view as FIG. 3 illustrating a second embodiment of the electronic control module housing supported in an opening formed in the mirror assembly case; 
     FIG. 7 is an exploded view of a mirror assembly with a back can member, illustrating a third embodiment with the electronic control module supported on a mounting bracket; 
     FIG. 8 is sectional view taken along line XIII--XIII of FIG. 7 illustrating a fourth embodiment with the electronic control module housing supported on an inner surface of the back can; and 
     FIG. 9 is a schematic view of the various electrical components and electronic components housed in the mirror assembly of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now specifically to the drawings and the illustrative embodiments depicted therein, the numeral 10 generally designates a modular exterior rearview mirror assembly of the present invention mounted to a vehicle 8 (FIGS. 1-5). Exterior rearview mirror assembly 10 includes an actuator support member 11 and a molded plastic mirror case 12. Actuator support member 11 may comprise a conventional mounting bracket, which extends through the casing and mounts onto a vehicle panel or may comprise a mounting bracket that is supported by the case of the mirror assembly. Details of the actuator support member 11 and means for attaching the exterior mirror assembly to the vehicle are not provided as they are conventional. Reference, however, is made to FIG. 7 for an example of an actuator support member and vehicle mounting bracket, which is formed on the case and attaches the exterior mirror assembly to a vehicle. 
     Case 12 houses a reflective element assembly 13. Reflective element assembly 13 includes a reflective mirror element 14 comprising a chrome coated glass member having a glass thickness of approximately 2.2 mm and a backing plate 16 which supports the reflective mirror element 14. Reflective assembly 13 may include a bezel plate or bezel assembly and may include one or more electrical components, such as a heater pad, an electro-optic element, an ultrasonic transducer, a light sensor module for adjusting the level of an electrochromic mirror element, a sensor for automatic headlights, blind spot detection systems, keyless entry systems, and the like. Backing plate 16 is supported by a mirror actuator assembly 20, which is turn is supported on actuator support member 11. 
     Case 12 also houses an electronic control module 22, which may be supported in a housing 24. Case 12 is generally cup-shaped and, preferably, injection molded from non-electrically conductive, nylon material. More preferably, mirror case 12 is injected molded from resinous ABS plastic, such as that sold under the trademark TERLURAN KR2889®, by BASF Company of Wyandotte, Mich. Alternately, other resinous, melt processible plastics or moldable materials such as glass filled nylon and polypropylene could be used to form case 12. A suitable nylon is 13% glass modified nylon 6:6 sold as ZYTEL 71G13L® by I.E. DuPont de Nemours &amp; Company of Wilmington, Del., or PA123G13BK-47 by Bay Resins Inc. of Millington, Md. A suitable polypropylene is TENITE P6M4Z-007® by Eastman Chemical Products, Inc., Kingsport, Tenn. 
     Reflective element 14 may comprise a conventional non-electro-optic mirror element including metallic reflector coated glass substrate such as with a thin chromium reflector coating or may include a non-metallic reflector, such as a dichroic such as is described in U.S. Pat. No. 5,207,492 to Roberts et al. or may be a reflector comprising a silicon reflective layer such as is discribed in U.S. Pat. No. 5,535,056 to Caskey et al. which is herein incorporated by reference. Alternatively, reflective element may comprise a variable reflective electro-optic element such as an electrochromic mirror element and may comprise one of several types of electrochromic elements--the electrochemichromic type, such as that disclosed in U.S. Pat. No. 5,140,455 issued to Varaprasad et al. and commonly assigned with the present application, the disclosure of which is hereby incorporated herein by reference or may be of the solid state type such as that disclosed in the U.S. Pat. No. 4,712,879 issued to Niall R. Lynam et al., U.S. patent application Ser. No. 08/023,675, filed Feb. 22, 1993 by Varaprasad et al., U.S. patent application Ser. No. 08/193,557, filed Feb. 8, 1994 by Varaprasad et al., and U.S. application Ser. No. 08/238,521, filed Mar. 5, 1994 by Varaprasad et al., now U.S. Pat. No. 5,668,663 all commonly assigned with the present application to Donnelly Corporation, the disclosures of which are herein incorporated by reference. Such electrochromic elements comprise an electrically responsive electrochromic medium that modulates reflectivity from a reflective element. Such electrochromic mirror elements are continuously variable and exhibit multiple partial reflectant states as the voltage applied thereto is varied. Alternatively, reflective element 14 may comprise other electro-optic mirror elements, such as a liquid crystal mirror and the like. 
     An electrochromic mirror element 14 is preferably driven by signals produced by a variable reflectance system of the type disclosed in U.S. patent application Ser. No. 08/316,047, for MODULAR VARIABLE REFLECTANCE MIRROR ASSEMBLY filed Sep. 30, 1994, by Kenneth L. Schierbeek et al., now U.S. Pat. No. 5,635,281 which is herein incorporated by reference. 
     Actuator assembly 20, which secures reflective mirror element 14 and backing plate 16 to actuator support member 11, is a two-axis positioning device that adjusts the position of the reflective mirror element 14 and the backing plate 16 about vertical and horizontal axes, as is know in the art. In the illustrative embodiment, actuator 20 may be Model No. H16-49-8001 (right hand mirror), Model No. H16-49-8051 (left hand mirror) marketed by Matsuyama of Kawagoe, Japan, or Model No. 540 marketed by Industrie Koot BV (IKU) of Montfoort, Netherlands. 
     Actuator assembly 20, which may also be a memory actuator of the type disclosed in U.S. Pat. No. 5,196,965 to Lang et al. entitled REARVIEW UNIT FOR MOTOR-VEHICLES, is powered by a vehicle battery voltage, ignition voltage or a 12-volt supply by a power line. Because the mirror assembly is to be used as an exterior mirror, a heater pad may be positioned against reflective mirror element 14 in order to remove ice and dew from mirror element 14. Such heater structure may be of the type disclosed in commonly assigned U.S. patent application Ser. No. 07/971,676, filed Nov. 4, 1992, by Niall R. Lynam et al. for an ELECTROCHROMIC MIRROR FOR VEHICLES, now U.S. Pat. No. 5,446,576 the disclosure which is hereby incorporated by reference. Also, an ultrasonic transducer, such as conventionally known, can be included to remove raindrops from the outer surface 14a of the reflective mirror element 14 such as disclosed in U.S. Pat. No. 5,012,593 issued to Shoji Okada et al. for DEVICE FOR REMOVING WATER DROPLETS. Alternatively, the outer surface 14a of the reflective element 14 can be wiped clean of water droplets and general debris by means of an exterior mirror wiper blade (not shown), which is commonly known in the exterior mirror assembly art. 
     Electronic control module 22 includes an integral carrier member 27, such as a conventional circuit board, for example a PCB, on which one or more electronic devices are installed. In some applications, it may be necessary to treat the electronic control module with a conformal coating, which provides a moisture barrier for the electronic devices and electrical circuitry mounted on the circuit board. Conventional methods of conformal coating include dipping of a circuit board into a conformal agent. In some instances, double dipping may be required. After a first application of the conformal agent is dried, the circuit board is dipped again to provide a second coating to provide further assurances that the circuit board is completely covered with the protective coating. 
     As best illustrated in FIG. 5, electronic control module 22 may include electronic devices including a memory device 27b for storing the positions for a memory mirror actuator assembly or an electronic device 27a, which is functionally interconnected electrically with one or more electrical components either in the mirror assembly case or in the vehicle compartment, such as the mirror actuator assembly 20, a heater pad, sensors for adjusting the reflectance level of an electrochromic mirror element and for automatic headlight activation, electro-optic mirror elements, blind spot detection systems, compass systems, intrusion detection systems, vehicle security lights and turn signal indicators, keyless entry systems, and trainable garage door opener systems. Similarly, the electronic module 22 may include an electrical distribution network 27c, such as disclosed in co-pending application, entitled VEHICLE MIRROR DIGITAL NETWORK AND DYNAMICALLY INTERACTIVE MIRROR SYSTEM, Ser. No. 08/679,681 filed on Jul. 11, 1996 (attorney Docket DONO1 P628), which is incorporated by reference herein. As shown in FIG. 9, the network 27c may include all the previously described electronic devices. But it should be understood that FIG. 9 is for illustrative purposes only and that network 27c may include only one of the electronic devices. Furthermore, these devices may be individually supported on the module 22. Electronic control module 22 may similarly support an antenna 27d for a cellular phone system, a Global Positioning System (GPS), a garage door opener, including an electronically trainable garage door opener disclosed in U.S. Pat. No. 5,479,155 issued to Zeinstra et al., or the like. In the case of the cellular phone system, antenna 27d is coupled through a lead 39b that extends through the mirror assembly case into the compartment of the vehicle to the cellular phone system receiver 29. Moreover, the electronic control module 22 may support a GPS system 29e, including a GPS receiver, which would communicate to the GPS satellites through the GPS antenna, also supported on the electronic control module 22. 
     As best seen in FIG. 3, electronic control module 22 may be supported by the electronic control module housing/cover. The housing comprises a compartment 24, which is preferably injection molded from non-electrically conductive, nylon material. More preferably, compartment 24 is injected molded from resinous ABS plastic, such as TERLURAN KR2889®. Alternately, compartment 24 may comprise other resinous, melt processible plastics or moldable materials such as glass filled nylon and polypropylene. A suitable nylon is 13% glass modified nylon 6:6 sold as ZYTEL 71G13L® or PA123G13BK-47. A suitable polypropylene is TENITE P6M4Z-007. In order to support compartment 24 in case 12, case 12 includes support structure, such as the hook catch 29a and threaded boss 29b shown in FIGS. 3 and 4. Compartment 24 is generally rectangular in shape having a base wall 25 with an upper edge 24a, a lower edge 24b, and opposed side edges 24c and 24d. Extending between side edges 24c and 24d on base wall 25 are shoulders 30 and 31 that provide flat mounting surfaces and bearing support for electronic control module 22. Shoulder 30 includes integrally formed projecting pins 32 for engaging corresponding openings 33 formed on one end portion of integral carrier member 27. The other end portion of carrier member 27 is anchored to shoulder 31 by a fastener 34, preferably a self tapping screw or other suitable releasable fasteners. In order to reduce vibration of compartment 24 and to prevent moisture and debris from entering compartment 24, a sealing surface 35 is provide around the perimeter of the compartment 24. Sealing surface 35 engages and seals against inner surface 12a of case 12. As best seen in FIG. 5, compartment 24 includes a flange 36 with a hook shaped edge 36a for engaging hook catch 29a of case 12 and a pair of screw flanges 37 with fastener holes 37a extending therethrough for receiving fasteners 38, which extend through screw flanges 37 and into threaded bosses 29b. It should be understood that other similar structures may be used for releasably anchoring the compartment 24 in the case 12, such as snap fit, screw type, or other releasable fasteners. 
     The electronic devices on electronic control module 22 are powered through externally extending power leads 39a that couple to a vehicle wiring bus, such as powered by an ignition switch or a 12-volt battery (not shown). As best shown in FIG. 3, power leads 39a extend from electronic control module 22 through compartment 24 and through an opening 40 provided in case 12. Electronic control module 22 further includes leads 39b and 41 for coupling the electronic controls to the various electrical components that are inside and outside the case 12. As shown, leads 41 extend through electronic control module compartment 24 to reflective element 14, mirror actuator assembly 20, and other electrical components 42a, such as a light sensor module for the variable reflectance control system, a heater pad, sensors for adjusting the reflectance level of an electrochromic mirror element and for automatic headlights, electro-optic mirror elements, blind spot detection systems, compass systems, intrusion detection systems, vehicle security lights and turn signal indicators, keyless entry systems, and trainable garage door opener systems. Leads 39b extend through opening 40 to couple to various electrical components that may be outside the exterior mirror assembly, such as a cellular phone receiver 29, automatic headlight systems, security systems, GPS systems, IVHS systems, light indicator systems, and the like. It should be understood, that a GPS system, a security system, and a light indicator system may also be housed in the mirror assembly case. 
     To provide interconnection with electronic control module 22, compartment base wall 25 includes at least one opening through which electrical leads extend to connect to the electronic control module 22. Preferably, base wall 25 includes a pair of openings 25a and 25b, one for the electrical leads 39a and 39b that extend through opening 40 in case 12 for external connections and the other for the electrical leads 41 that couple the module 22 to the various electrical components in the mirror assembly case. Holes 25a and 25b each may include a grommet 43 to seal the electronic control module compartment and to protect the leads 39a, 39b, and 41 from damage that may result from rubbing against the edge of openings 25a and 25b. Grommets 43 are conventional and typically comprise a generally elastomeric material, such as EPDM, rubber, or silicone. Alternatively, holes 25a and 25b may support connectors through which leads 39a, 39b, and 41 electrically couple to the electronic control module 22. 
     Referring to FIG. 6, a second preferred embodiment of an electronic control module housing comprises an integrally molded insert 44 that is adapted to be inserted into an opening 45 provided in mirror assembly case 12&#39;. Insert 44 includes an outer wall 46 and an inner wall 48, which define an enclosure 49 therebetween, and is supported on shoulders 45a provided on the inner surface 12a&#39; of case 12&#39; adjacent opening 45. Insert 44 is inserted into and supported in opening 45 such that outer wall 46 is aligned flush with the wall 50 of case 12&#39; and, therefore, becomes a part of the mirror assembly case 12&#39;. Inner wall 48 supports electronic control module 22 in enclosure 49 on a pair of shoulders 51a and 51b, which provide flat mounting surfaces and bearing support for module 22. Module 22 may be secured to inner wall 48 in the same manner as described in reference to the previous embodiment. Module 22 includes electrical leads 39a for coupling the electronic control module 22 to the power supply, leads 39b for coupling to various electrical components outside the mirror assembly, such as the cellular phone system receiver or the automatic headlight system or the like, and leads 41 for coupling to the various electrical components inside the mirror assembly case 12&#39;. Similarly to the first embodiment, inner wall 48 includes apertures 48a and 48b to accommodate leads 39a and 39b and 41, which extend through inner wall 48 to electronic control module 22. 
     In this preferred embodiment, a pre-assembled electronic control module and electronic control module housing is disclosed in the form of an insertable modular unit. The insertable modular unit reduces the number of installation steps by incorporating the electronic control module into the housing. Moreover, the modular unit is simple to remove for service or replacement. 
     In another preferred embodiment, shown in FIG. 7, the mirror assembly 10&#34; includes a back can member, shell, or outer wall 54. In this embodiment, the mirror assembly 10&#34; includes a case 12&#34; housing and supporting mirror actuator assembly 20 on actuator support member 11&#34;, which in turn supports a reflective element assembly 13&#34;. Reflective element assembly 13&#34; includes reflective element 14 and backing plate 16 and may include a bezel plate or bezel assembly (not shown) and may include one or more electrical components, such as a heater pad, an electro-optic element, an ultrasonic transducer, a light sensor module for adjusting the level of an electrochromic mirror element, a sensor for automatic headlights, blind spot detection systems, keyless entry systems, and the like. Reflective element 14 may be mounted on backing plate 16 by an adhesive layer 14b and further supported on backing plate 16 by a lip 16a, which extends outwardly from the perimeter of backing plate 16 and surrounds and holds reflective element 14. Actuator support member 11&#34; includes a central support member 55 for actuator assembly 20 and a pair of arms 56 that extend from central support member 55 to side walls 57 and 58 of the case 12&#34;. Case 12&#34; includes a base 59 for mounting the mirror assembly 10&#34; to a vehicle mounting bracket 60. Back can member 54 includes a pair of tabs 54a and 54b which snap onto receiving structures on the side walls 57 and 58 of the case 12&#34;. Preferably, back can 54 is preferably nylon. More preferably, back can 54 is injection molded from resinous ABS plastic, such as TERLURAN KR2889®. Alternately, back can 54 may comprise other resinous, melt processible plastics or moldable materials such as glass filled nylon and polypropylene. A suitable nylon is 13% glass modified nylon 6:6 sold as ZYTEL 71G13L® or PA123G13BK-47. A suitable polypropylene is TENITE P6M4Z-007. Back can 54 snaps on to the mirror assembly case 12&#34; to establish the color or texture of the mirror assembly case 12&#34; so that it matches the vehicle on which it is to be mounted. 
     In this embodiment, electronic control module 22 is supported on actuator support member 11&#34; independently of the reflective element 14 and the mirror actuator assembly 20. Preferably, actuator support member 11&#34; includes a receptacle for supporting and providing an enclosure 62 for electronic control module 22. Furthermore, the electronic control module 22 may be injection molded with the actuator support member 11&#34; to provide an encapsulation of the electronic control module 22 in the actuator support member 11&#34;. 
     In yet another embodiment, electronic control module 22 is supported on back can 54. As best seen in FIG. 8, electronic control module 22 is supported on inner surface 54a of the back can 54 between shoulders 54b and 54c. Electrical interconnection with the electronic control module 22 is made through an opening 65 defined by the perimeter of the side walls 57 and 58 and top and bottom walls 66 and 67 of casing 12&#34;. As with the previously described embodiments, the installation process is greatly simplified. The service or replacement of the electronic control module 22 is even further improved. 
     Mounting the electronic control module 22 remotely from the reflective element assembly serves several functions. By removing the weight of the electronic devices from the reflective element assembly and redistributing their weight to the case, or in the case of the third embodiment onto a rigid actuator support member, the vibration in the mirror actuator assembly is significantly reduced. Vibration can cause undesirable distortion in the reflected image. Vibration may also shorten the operational life of the several components in the mirror assembly housing that are subjected to the vibration. In addition, by removing some or all the electronic controls from the reflective element assembly the inherent space limitations are improved, possibly creating sufficient space for other components that were previously omitted. Furthermore, the improved but still limited space may make the other components more accessible for service or replacement. The mirror assembly is also easier to assemble-the electronic control module housing, which supports a plurality of electronic controls, is simply inserted into case 12 or 12&#39;. In the third embodiment, the electronic control module is simply inserted in to the back can of the mirror assembly case 12&#34;. 
     While several forms of the invention have been shown and described, other forms will now be apparent to those skilled in the art. For instance, the electronic control module may be a potted module, thereby forming a protective housing around the electronic control module, which may attach to the mirror assembly case. Moreover, the electronic control module may be insert molded with the mirror assembly case or encapsulated in the wall of the case, in which the case provides the housing for the electronics module. Also, while illustrated herein for application to an exterior rearview mirror assembly, the concept of this invention can also be beneficially applied to an interior rearview mirror assembly, whether windshield-mounted or header-mounted. 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 claims which follow.