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 divisional application of application Ser. No. 09/477,539, filed Jan. 4, 2000, now U.S. Pat. No. 6,217,181, by Niall R. Lynam, Desmond J. O&#39;Farrell, and Roger L. Veldman, entitled MODULAR REAR VIEW MIRROR ASSEMBLY INCLUDING AN ELECTRONIC CONTROL MODULE, which is a divisional application of application Ser. No. 08/702,228, filed on Aug. 23, 1996, by Niall R. Lynam, Desmond J. O&#39;Farrell, and Roger L. Veldman, entitled MODULAR REAR VIEW MIRROR ASSEMBLY INCLUDING AN ELECTRONIC CONTROL MODULE, now U.S. Pat. No. 6,019,475, which 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 and 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 REAR VIEW 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, now U.S. Pat. No. 5,786,772, 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. 08/277,674 filed Jul. 19, 1994, by Kenneth L. Schierbeek and Niall R. Lynam, for an AUTOMATIC REARVIEW MIRROR SYSTEM WITH AUTOMATIC HEADLIGHT ACTIVATION, now U.S. Pat. No. 5,715,093, 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 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 accommodate 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 rearview mirror 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 described in U.S. Pat. No. 5,535,056 to Caskey et al. which is herein incorporated by reference. Alternatively, reflective element  14  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, now U.S. Pat. No. 5,635,281, by Kenneth L. Schierbeek et al., 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  14   a  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  14   a  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  27   b  for storing the positions for a memory mirror actuator assembly or an electronic device  27   a , 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  27   c , 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, now U.S. Pat. No. 5,798,575, which is incorporated by reference herein. As shown in  FIG. 9 , the network  27   c  may include all the previously described electronic devices. But it should be understood that  FIG. 9  is for illustrative purposes only and that network  27   c  may include only one of the electronic devices. Furthermore, these devices may be individually supported on the module  122 . Electronic control module  22  may similarly support an antenna  27   d  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  27   d  is coupled through a lead  39   b  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 an GPS system  29   e , 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  29   a  and threaded boss  29   b  shown in  FIGS. 3 and 4 . Compartment  24  is generally rectangular in shape having a base wall  25  with an upper edge  24   a , a lower edge  24   b , and opposed side edges  24   c  and  24   d . Extending between side edges  24   c  and  24   d  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  12   a  of case  12 . As best seen in  FIG. 5 , compartment  24  includes a flange  36  with a hook shaped edge  36   a  for engaging hook catch  29   a  of case  12  and a pair of screw flanges  37  with fastener holes  37   a  extending therethrough for receiving fasteners  38 , which extend through screw flanges  37  and into threaded bosses  29   b . 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  39   a  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  39   a  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  39   b  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  42   a , 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  39   b  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  25   a  and  25   b , one for the electrical leads  39   a  and  39   b  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  25   a  and  25   b  each may include a grommet  43  to seal the electronic control module compartment and to protect the leads  39   a ,  39   b , and  41  from damage that may result from rubbing against the edge of openings  25   a  and  25   b . Grommets  43  are conventional and typically comprise a generally elastomeric material, such as EPDM, rubber, or silicone. Alternatively, holes  25   a  and  25   b  may support connectors through which leads  39   a ,  39   b , 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 ′. Insert  44  includes an outer wall  46  and an inner wall  48 , which define an enclosure  49  therebetween, and is supported on shoulders  45   a  provided on the inner surface  12   a ′ of case  12 ′ 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 ′ and, therefore, becomes a part of the mirror assembly case  12 ′. Inner wall  48  supports electronic control module  22  in enclosure  49  on a pair of shoulders  51   a  and  51   b , 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  39   a  for coupling the electronic control module  22  to the power supply, leads  39   b  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 ′. Similarly to the first embodiment, inner wall  48  includes apertures  48   a  and  48   b  to accommodate leads  39   a  and  39   b  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 ″ includes a back can member, shell, or outer wall  54 . In this embodiment, the mirror assembly  10 ″ includes a case  12 ″ housing and supporting mirror actuator assembly  20  on actuator support member  11 ″, which in turn supports a reflective element assembly  13 ″. Reflective element assembly  13 ″ 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  14   b  and further supported on backing plate  16  by a lip  16   a , which extends outwardly from the perimeter of backing plate  16  and surrounds and holds reflective element  14 . Actuator support member  11 ″ 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 ″. Case  12 ″ includes a base  59  for mounting the mirror assembly  10 ″ to a vehicle mounting bracket  60 . Back can member  54  includes a pair of tabs  54   a  and  54   b  which snap onto receiving structures on the side walls  57  and  58  of the case  12 ″. 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 ″ to establish the color or texture of the mirror assembly case  12 ″  50  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 ″ independently of the reflective element  14  and the mirror actuator assembly  20 . Preferably, actuator support member  11 ″ 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 ″ to provide an encapsulation of the electronic control module  22  in the actuator support member  11 ″. 
   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  54   a  of the back can  54  between shoulders  54   b  and  54   c . 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 ″. 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 ′. In the third embodiment, the electronic control module is simply inserted in to the back can of the mirror assembly case  12 ″. 
   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.