A rear view mirror assembly

The present invention relates to a rear view mirror assembly of a vehicle, and more particularly to a base member for installing the rear view mirror assembly on a windshield of a vehicle as specified in the preamble of Claim 1 and as disclosed for example in EP-A-0 085 004.

An adjustable device disposed between a base member and a support arm of a rear view mirror is disclosed in Japanese Utility Model Laid-open No. Showa 58-24595. In this Japanese Utility Model Laid-open No. Showa 58-24595, the rear view mirror includes a support arm, a spring and a base member. The base member is cemented on an interior of a windshield, and includes a bar and a mounting portion. The spring includes a hooked end and a rear edge, and the hooked end being mounted on the bar of the base member. The rear edge of the spring is disposed on the mounting portion, and the support arm is fixed on the spring by a bolt.

Further, the base member includes a slanted surface on a bottom surface thereof and the support arm includes an incline on an end thereof. As shown in Fig. 12 of Japanese Utility Model Laid-open No. Showa 58-24595, when a force "Pc" is applied to the rear view mirror, the support arm is moved downwardly and breaks away, because the incline of the support arm and the slanted surface of the base member prevent the support arm from resisting the force "Pc".

Furthermore, this reav view mirror assembly includes a spherical ball portion disposed on an opposite end of the support arm, the ball portion being received within a socket portion of the rear view mirror.

Therefore, this rear view mirror can be adjusted to its angle through the spherical ball portion and the socket portion of the rear view mirror. However, the range of the adjustment of this rear view mirror is rather small, because this rear view mirror includes only one adjustment device. In addition, it is not easy for a worker to install the components of the rear view mirror because the worker must install the nut of the spring into the hole of the support arm and then fix the support arm on the spring with a bolt. Such installment procedures are cumbersome and complex.

A suitable material for a base member for mounting a rear view mirror assembly is disclosed in Japanese Utility Model Application Laid-open No. Showa 57-29443. In this publication, the suitable material is sintering stainless steel which has a similar coefficient of thermal expansion to a coefficient of thermal expansion of a windshield. That is, the base member which is made of sintering stainless steel expands at a similar rate of expansion as the windshield heated by the sun. In the publication Laid-open No. Showa 57-29443, the coefficient of thermal expansion of the windshield is 9x10-⁹ mm/mm/°C, and the coefficient of thermal expansion of the base member which is made of the sintering stainless steel is from 9x10-6 mm/mm/°C through 12x 10-⁶ mm/mm/°C.

Generally, sintering stainless steel has many pores therein, and the base member which is made of the sintering stainless steel is cemented to the windshield through an adhesive. Therefore, pores exist between the adhesive and a contact surface of the base member, and air exists in each of the pores. When the sun heats the windshield and the base member, the air expands in the pore and tends to separate the base member from the windshield in spite of the adhesive.

Accordingly, air passages are formed between the adhesive and the contact surface of the base member, and the adhesion of between the windshield and the base member is weakened by the air passages.

The present invention has been developed in view of the foregoing background and to overcome the foregoing drawbacks. It is accordingly an object of this invention to provide a base member of a rear view mirror assembly which is securely cemented to a windshield of a vehicle.

It is another object of the present invention to provide a base member of a rear view mirror assembly which expands at a similar rate of a thermal expansion as the windshield expands with heat of the sun.

In order to accomplish the above-described objects, a rear view mirror assembly according to the present invention includes all features of independent claim 1, namely a first base member and a first unit of the rear view mirror assembly. The first base member is cemented to a windshield of a vehicle through an adhesive, and the first base member is made of rolled stainless steel.

The first base member has a contact surface which is smooth and does not have any pores therein, and the first base member has a similar coefficient of thermal expansion to a coefficient of thermal expansion of the windshield.

Therefore, air does not exist between the adhesive and the contact surface of the first base member. Air passages are not formed between the windshield and the first base member of the rear view mirror assembly, even if the windshield expands with the heat of sun, because the contact surface of the first base member does not have any pores therein.

Further, the first base member of the rear view mirror assembly can expand at a similar rate of expansion as the windshield, when the sun heats the windshield and the first base member, because the first base member has almost the same coefficient of thermal expansion as the coefficient of thermal expansion of the windshield.

Accordingly, the first base member can be securely cemented to the windshield through the adhesive.

The above objects, features and advantages of the present invention will become more apparent from the description of the invention which follows, taken in conjunction with the accompanying drawings, wherein like reference numerals denote like elements, and wherein: <ul id="ul0001" list-style="none"><li>Fig. 1 is a perspective view showing a rear view mirror assembly according to the present invention;</li><li>Fig. 2 is an enlarged cross-sectional view of the rear view mirror assembly of a first embodiment, taken along the line II-II in Fig. 1;</li><li>Fig. 3 is an enlarged perspective view showing components of the rear view mirror assembly shown in Fig. 1 in a disassembled condition;</li><li>Fig. 4 is a cross-sectional view of the second base member of the rear view mirror assembly of Fig. 3 taken along the line IV-IV of the Fig. 3;</li><li>Fig. 5 is a cross-sectional view of the first base member of the rear view mirror assembly of Fig. 3, taken along the line V-V of Fig. 3;</li><li>Fig. 6 is a cross-sectional view of the second base member mounted to the first base member of the rear view mirror assembly, taken along the line V-V of Fig. 3;</li><li>Fig. 7 is a cross-sectional view of the rear view mirror assembly of Fig. 2, which shows the support arm rotated about a central rotational point 17 of the support arm in the clockwise direction of Fig. 2 when a force "F₁", is applied to the support arm in the horizontal direction of Fig. 2;</li><li>Fig. 8 is a cross-sectional view of the rear view mirror assembly of Fig. 2 which shows the support arm rotated about the central point 17 in the clockwise direction in an amount greater than the condition illustrated in Fig. 7;</li><li>Fig. 9 is a cross-sectional view of the rear view mirror assembly of Fig. 2, which shows the force "F₁" applied to the support arm along the line connecting the central point 17 of the support arm to a central point for the rotation of the rear view mirror;</li><li>Fig. 10 is a cross-sectional view of the rear view mirror assembly of Fig. 2, which shows the support arm rotated about a contact point 27 between a mounting member and a base member in the clockwise direction;</li><li>Fig. 11 is an enlarged perspective view of the rear view mirror assembly of a second embodiment, illustrating the components in a disassembled condition;</li><li>Fig. 12 is an enlarged perspective view of the rear view mirror assembly of a third embodiment, illustrating the components in a disassebmbled condition; and</li><li>Fig. 13 is an enlarged cross-sectional view of the rear view mirror assembly of a fourth embodiment, taken along the line II-II in Fig. 1.</li></ul>

The present invention will be described in detail with reference to the accompanying drawings which illustrate different embodiments according to the present invention.

Referring to Figure 1, a rear view mirror assembly is disposed at an upper central portion of a windshield 1 of a vehicle. A rear view mirror 25 is rotatably mounted on an inner surface of the windshield 1 through a support arm 15, a mounting member 14 and a first base member 3.

As shown in Figure 2 and Figure 3, the first base member 3 is cemented by an adhesive 2 to the windshield 1. The first base member 3 is made of rolled stainless steel. The first base member 3 has a smooth contact surface which does not have any pores therein, and a similar coefficient of thermal expansion as a coefficient of thermal expansion for the windshield 1.

Therefore, air does not exist between the adhesive 2 and the contact surface of the first base member 2. Air passages are not formed between the windshield 1 and the first base member 3 of the rear view mirror assembly, even if the sun heats the windshield 1 and the first base member 3, because the contact surface of the first base member 3 does not have any pores therein. Further, when sunshine heats the windshield 1 and the first base member 3, the first base member 3 of the rear view mirror assembly expands at a similar rate of expansion as the windshield 1, because the first base member 3 has almost the same coefficient of thermal expansion as a coefficient of thermal expansion of the windshield 1.

The first base member 3 includes a plurality of first flanges 304, 305 and a second flange 307. Each of the plurality of first flanges 304, 305 is disposed on a side portion of the first base member 3.

As shown in Figure 5, the first flange 305 has a plate which extends horizontally, and parallels a main plate 311 of the first base member 3. As shown in Figure 3, the first flange 305 extends downwardly from the side portion of the main plate 311 of the first base member 3, and is bent toward an inside of the first base member 3.

The second flange 307 is disposed on a front portion of the first base member 3, and includes a second stopper 336 and a pawl 306. The second stopper 336 is on a vertical portion of the second flange 307 which extends downwardly from the main plate 311 of the first base member 3. The pawl 306 is disposed on a horizontal portion of the second flange 307 which extends from a lower part of the vertical portion of the second flange 307. The pawl 306 is biased upwardly toward the main plate 311.

A first unit for installing the rear view mirror assembly on the windshield 1 includes a second base member 5, a spring 9, the mounting member 14, the support arm 15, a second ball member 18 and a bolt 19.

The second base member 5 is mounted on the plurality of first flanges 304, 305 and the second flange 307 of the first base member 3. The second base member 5 includes a plurality of upper projections and a plurality of lower projections which are disposed on both sides of the second base member 5. Each projection of the lower projections and the upper projections has an inner surface. As shown in Figure 4 and Figure 6, a gash 510 is defined between the inner surfaces of the lower projections and the inner surfaces of the upper projections on each side of the second base member 5. The plates of the first flanges 304, 305 of the first base member 3 are inserted into the gash 510 on each side of the second base member 5. A rearmost projection (i.e., furthest from the pawl 306) on each side of the second base member 5 includes a third stopper 512 and an inclined inner surface 511, so that a rear portion of the plate of the first flange 305 of the first base member 3 is bent along the inclined inner surface 511 of the rearmost projections of the second base member 5. Accordingly, the plates of the first flanges 304, 305 of the first base member 3 securely engage with the inner surfaces of the projections of the second base member 5.

The second stopper 336 of the second flange 307 of the first base member 3 and the third stopper 512 of the rearmost projection of the second base member 5 prevent the second base member from being inserted more than a predetermined distance on a plurality of the first flanges 304, 305 and the second flange 307 of the first base member 3.

The second base member 5 includes an engagement recess 509 which is defined on a bottom surface thereof, and the pawl 306 of the second flange 307 of the first base member 3 engages with the engagement recess 509 of the second base member 5. Therefore, the pawl 306 of the first base member 3 prevents the second base member 5 from moving between the plurality of the first flanges 304, 305 and the second flange 307 of the first base member 3.

The second base member 5 includes a mounting portion 271 which is disposed in the vicinity of an outer peripheral edge thereof, and is on a substantially flat horizontal surface. A hook 6 extends from an inner portion of the mounting portion 271. The hook 6 has an inner peripheral edge and an upper surface, the inner peripheral edge defining an opening 4 within the second base member 5. The upper surface of the hook 6 has a plurality of second projections 8 and a plurality of second recesses 7 thereon.

A spring 9 is disposed within the opening 4 of the second base member 5. The spring 9 includes a cap 10, a plurality of first projections 11 and a plurality of first recesses 12. The cap 10 is fixed at a central portion of the spring 9, and includes a cavity 102 with an inner end 101 therein. The cavity 102 of the cap 10 includes a screw hole therein.

The plurality of first projections 11 of the spring 9 extend outwardly in its radial direction, and engage with the plurality of second recesses 7 of the second base member 5. Therefore, the spring 9 engages securely with the second base member 5, so that the spring 9 cannot rotate in the opening 4 of the second base member 5. Further, the spring 9 can support a predetermined amount of a downward vertical force so that the spring 9 can break away from the hook 6, when more than the predetermined amount of the downward vertical force is applied to the spring 9.

The mounting member 14 is disposed on the mounting portion 271 of the second base member 5. The mounting member 14 includes an upper peripheral edge 272 and a first socket portion 13. The upper peripheral edge 272 is in contact with the mounting portion 271 of the second base member 5, and the first socket portion 13 of the mounting member 14 is formed in a lower surface of the mounting member 14. The first socket portion 13 is formed in a semi-spherical concave shape, and has a first aperture 141 at the central portion of the mounting member 14.

The support arm 15 is pivotally mounted on the first socket portion 13 of the mounting member 14. The support arm 15 has an opposite end 24. The end 16 of the support arm 15 includes an outer surface and an inner surface. The outer surface of the support arm 15 has a first ball portion 161 thereon formed in a semi-spherical convex shape. The first ball portion 161 is mounted on the first socket portion 13 of the mounting member 14. The inner surface of the support arm 15 includes a second socket portion 162 which is formed in a semi-spherical concave shape. The inner surface of the support arm 15 defines a recess within the end 16 of the support arm 15, and a second aperture 21 is opened between the second socket portion 162 of the inner surface of the support arm 15 and the first ball portion 161 on the outer surface of the support arm 15. The second aperture 21 has an inner peripheral edge. A diameter of the second aperture 21 is greater than the diameter of the first aperture 141 of the mounting member 4.

A curved or second ball member 18 having an upper semi-spherical convex surface is slidably mounted on the second socket portion 162 of the supporting arm 15. The second ball member 18 has a third aperture 181 and a plurality of protrusion 22 on its convex surface. Preferably, at least three protrusions 22 are disposed on the upper semi-spherical convex surface. The protrusions 22 are normally located within the inner peripheral edge of the second aperture 21.

A bolt 19 is provided for securing the various components together. The bolt 19 includes a head portion on an end thereof adjacent the second ball member 18. The opposite end of the bolt 19 is inserted into the cavity 102 in the cap 10 of the spring 9. An intermediate shank portion of the bolt 19 extends through the third aperture 181 of the second ball member 18, the second aperture 21 of the support arm 15, and the first aperture 141 of the mounting member 14. A diameter of the second aperture 21 is greater than the diameter of the first aperture 141 and the third aperture 181, so that the support arm 15 is supported for universal movement. That is, the support member 15 can rotate about the vertical axis of the bolt 19 (Fig. 2), the protrusions 22 rotating within the second aperture 21. The support member 15 can also rotate about a central point 17 (Fig. 2) of the support arm 15 to an extent defined by the inner peripheral edge of the second aperture 21. Rotation about the central point 17 requires the inner surface of the support arm 15 to ride over the protrusions 22.

It should be apparent to one skilled in the art that the bolt 19 may be a screw or a rod.

The opposite end of the bolt 19 is prevented from being inserted into the cavity 102 of the cap 10 more than predetermined length by the inner end 101 of the cap 10, so that a bolt length defined between the cap 10andthe head portion of the bolt 19 is constant. The bolt length between the cap 10 and the head portion of the bolt 19 is greater than a sum of the thicknesses of the mounting member 14 around the first aperture 141, the supporting arm 15 around the second aperture 21, and the second ball member 18 around the third aperture 181.Therefore, the support arm 15can move along the longitudinal axis of the bolt 19, as well as rotating about a central portion 17 of the support arm 15.

ltwill be apparentto one skilled in the artthatthe bolt 19 may be integral with the second ball member 18.

The recess of the support arm 15 opens downward in a lower portion of the support arm 15, and a cover 23 is disposed within the recess. Therefore, the cover 23 covers the recess and improves the aesthetic appearance of the rear view mirror assembly.

The opposite end of the support arm 15 includes a ball portion 24, and the ball portion 24 formed in a spherical ball shape. The ball portion 24 is rotatably received in a spherical socket portion 241 which is defined within the rear view mirror 25.

When the bolt 19 engages the spring 9, a second unit of the rear view mirror assembly is formed and includes the bolt 19, the spring 9, the mounting member 14, the support arm 15 and the second ball member 18. When the second unit is attached to the second base member 5 by engaging the spring 9 on the hook 6, a first unit of the rear view mirror assembly is formed. The first unit can be attached to the first base member 3 as described above. When more than the predetermined amount of the downward vertical force is applied to the spring 9, the second unit of the rear view mirror assembly can break away from the second base member 5.

A washer 20 is disposed between the cap 10 and the mounting member 14. Preferably, the washer 20 is made of synthetic resin. The washer 20 includes a hole therein which is slightly smaller than a diameter of the bolt 19. Therefore, the washer 20 prevents the bolt 19 from moving easily in the hole of the washer 20, once the bolt 19 is inserted into the hole of the washer 20. Further, the washer 20 and the bolt 19 can unite the mounting member 14, the support arm 15 and the second ball member 18, such that these components cannot change their relative position during assembly of the rear view mirror. During assembly, these components (i.e., mounting member 14, support artm 15 and second ball member 18, all of which are united by the bolt 19 and the washer 20) are attached to the spring 9 by threading the bolt 19 into the cop 10 to form the second unit. The assembly of the second unit with the second base member 5 forms the first unit.

As shown in Figure 2, the plurality of protrusions 22 of the second ball member 18 are normally disposed in the second aperture 21 of the support arm 15, so that the plurality of protrusions 22 normally prevent the rotation of the support arm 15 about the central point 17. Therefore, it is convenient for a worker assemble the components into the second unit and to install the second unit of the rear view mirror assembly on the second base member 5, because these components cannot change their positions due to the interlocked relation between the protrusions 22 and the second aperture 21 of the support arm 15. That is, the insertion of the protrusion 22 within the second aperture 21 temporarily maintains the components in position during assembly. As noted above, once assembled, the inner surface of the support arm 15 can ride over the protrusions 22 to permit rotation about the central point 17.

The second unit is attached to the second base member 5 to form the first unit. The first unit is easily installed on a vehicle by sliding the second base member 5 between the flanges 304, 305 of the first base member 3. The second base member 5 is locked in the correct position on the first base member 3 by the second and third stoppers 336, 512, as well as engagement of the pawl 306 in the recess 509.

Consequently, assembly and installation of the rear view mirror in accordance with the present invention are simplified. Assembly and installation are thus less cumbersome and time consuming than known rear view mirror assemblies.

Description will be hereunder given of operation of the above-described embodiment.

As shown in Figure 7, the inner surface of the support arm 15 can ridyson the protrusion 22 of the second ball member 18, when a force "F₁" is applied to a central point 26 of the ball end 24 of the support arm 15. As a result of the force "F₁", the support arm 15 rotates about a central point 17 of the support arm 15. The intermediate shank portion of the bolt 19 limits the movement of the support arm 15 to rotate within a space defined by the second aperture 21. That is, the inner peripheral edge of the second aperture 21 contacts the intermediate shank portion of the bolt 19 and thus limits the rotation of the support arm 15 about the central point 17.

When the force "F₁" is continuously applied to the support arm 15 in the horizontal direction in Fig. 7, a first moment M₁ in the clockwise direction about a point 28 is calculated by a first formula (1) as follows:<maths id="math0001" num=""><img file="EP0169734B1_D0001.tif" /></maths>

In this first formula (1), 1₁ is a vertical length between the point 28 and the central point 26 of the ball end 24 forthe rear view mirror 25. The point 28 is defined between the first ball portion 161 of the support arm 15 and an edge of the first socket portion 13 of the mounting member 14.

A second moment "M₂" in the clockwise direction about point 28 in Fig. 7 is calculated by the second formula (2) as follows:<maths id="math0002" num=""><img file="EP0169734B1_D0002.tif" /></maths>

In the second formula (2), 1₂ is the horizontal length between point 28 and the bolt 19, and "F2" is a downward vertical force on the bolt 19. The resiliency of the spring 9 resists the force "F2".

For equilibrium, M₁ must equal M₂. Therefore, the downward vertical force "F2" along the bolt 19, which is applied to the spring 9, is calculated by a third formula (3) as follows:<maths id="math0003" num=""><img file="EP0169734B1_D0003.tif" /></maths>

In Figure 8, a force "F_a" is applied to the central point 26 and a downward vertical force "F₄" is applied to the spring 9. If the force "F₃" is larger than the force "F_l", and a force "F₄" is not larger than the predetermined downward vertical force, the support arm 15 is further rotated about the point 28. The first ball portion 161 of the support arm 15 separates partially from the first socket portion 13 of the mounting member 14, and the support arm 15 is supported by the spring 9. In this condition, the force "F₄" is balanced with a bias force "Fs" of the spring 9 so that the moments generated about the point 28 are equal. The force "F_Q" is calculated by a fourth formula (4) as follows:<maths id="math0004" num=""><img file="EP0169734B1_D0004.tif" /></maths>

Next, if the force "F₃" becomes larger, and the force "F4" becomes larger than the predetermined amount of the downward vertical force, the spring 9 can break away from the hook 6 of the second base member 5. Concurrently the first unit of the rear view mirror assembly can break away when the spring 9 separates from the hook 6.

As shown in Figure 9, when the force "F₁" is applied to the support arm 15 along the line which connects the central point 26 to the central point 17 of the support arm 15, the support arm 15 cannot be rotated about the central point 17.

However, the vertical and horizontal components F_1v, F_lh of the force F₁ cause a third moment M₃ in the clockwise direction about a point 27, the point 27 being defined between the mounting portion 271 of the second base member 5 and the upper edge 272 of the mounting member 14. The third moment M₃ in the clockwise direction about the point 27 is calculated by a fifth formula (5) as follows:<maths id="math0005" num=""><img file="EP0169734B1_D0005.tif" /></maths>

In this fifth formula (5), 1₃ is a vertical length between the point 27 and the central point 26 of the rotation of the rear view mirror 25, and I₅ is a horizontal length between the point 27 and the point 26.

Therefore, as shown in Figure 10, the support arm 15 and the mounting member 14 can be rotated about the point 27, so that the upper edge 272 of the mounting member 14 separates partially from the mounting portion 271 of the second base member 5. In this case, both of the support arm 15 and the mounting member 14 are supported by the spring 9. In Figure 10, a downward vertical force "F₆" along the bolt 19 generates a fourth moment M₄ in the clockwise direction about the point 27. The fourth moment M₄ is calculated by the following sixth formula (6):

<maths id="math0006" num=""><img file="EP0169734B1_D0006.tif" /></maths>

In this sixth formula (6), 1₄ is a horizontal length between the point 27 and the bolt 19.

If M₃ equals M₄, then the force F₆ along the bolt 19 is balanced with a bias force "F," of the spring 9 and calculated by a seventh formula (7) as follows:<maths id="math0007" num=""><img file="EP0169734B1_D0007.tif" /></maths>

Next, if the force "F₁" increases and the force "F₆" becomes larger than the predetermined amount of the downward vertical force, the spring 9 can break away from the hook 6 of the second bar member 5. Therefore, the first unit of the rear view mirror assembly can break away.

A second embodiment of a rear view mirror assembly is shown in Figure 11. The second embodiment is similar to the first embodiment disclosed in Figure 2. However, the second embodiment has several differences disclosed hereunder.

The first base member 3 is cemented to a windshield 1 by an adhesive 2. The first base member 3 is made of a rolled stainless steel so that a contact surface of the first base member 3 has a smooth surface without pores and a similar coefficient of thermal expansion as the coefficient of thermal expansion for the windshield 1. Thus, air does not exist between the contact surface and the windshield 1 so that air passages are not formed. Further, the first base member 3 and the windshield 1 will expand at the same approximate rate when heated by the sun.

The first base member 3 has a pair of first flanges 304, 305, each having a plate. Each plate of the first base member 3 has a protrusion 334 which projects upwardly toward the main plate 311. In addition, the protrusion 334 of the first base member 3 is biased upwardly. Once assembled, the protrusion 334 of the first base member 3 is in contact with an inner surface 532 of an upper projection of a second base member 5, so that the protusion 334 of the first base member 3 biases the second base member 5 on a main plate 311 of the first base member 3.

Each of the pair of the first flanges 304, 305 includes a first stopper 335 which is disposed on a front end of each of a pair of the first flanges 304, 305 adjacent the second flange 307. The first stopper 335 of each of the first flanges 304, 305 is a spring, which prevents the second base member 5 from being inserted more than a predetermined distance on the first flanges 304, 305 and the second flange 307 of the first base member 3.

The protrusion 334 and the first stopper 335 of the first flange 305 of the first member 3 prevent the second base member 5 from vibrating in a space which is defined between the plates of the first flanges 304, 305 and the main plate 311 of the first base member 3 in the vertical and longitudinal directions of the vehicle. Like the first embodiment, the second embodiment facilitates installation of the rear view mirror assembly.

A third embodiment of rear view mirror assembly is shown in Figure 12. The third embodiment is similar to the first embodiment disclosed in Figure 3. However, the third embodiment has several differences disclosed hereunder.

The first base member 3 is cemented to a windshield 1 by an adhesive 2. The first base member 3 is made of rolled stainless steel so that a contact surface of the first base member 3 does not have any pores thereon. In addition, the first base member 3 has a similar coefficient of thermal expansion as the coefficient of thermal expansion for the windshield 1. Thus, air does not exist between the contact surface and the windshield 1 so that air passages are not formed. Further, the first base member 3 and the windshield 1 will expand atthe same approximate rate when heated by the sun.

The first base member 3 includes a wall 313, a first flange 314, a pair of holes 317 and a pair of clamping tabs 315. The wall 313 extends downwardly from a main plate 311 of the first base member 3 and is formed in a letter'U' shape. The first flange 314 of the first base member 3 extends horizontally from a lower edge of the wall 313, and parallels the main plate 311 of the first base member 3. Each of a pair of holes 317 of the first base member is opened in each of side portion of the wall 313, and each of the clamping tabs 315 extends horizontally from each of a pair of rear ends of the wall 313. The clamping tab 315 of the first base member 3 are spring biased toward an inside of the first base member 3. A space is defined between the main plate 311 and an upper edge of the clamping tab 315, and a rear end of the clamping tab 315 is bent back outwardly.

A second base member 5 includes an outer peripheral wall 520, a pair of pawls 521, and a step thereon. A front portion of the outer peripheral wall 520 of the second base member 5 is in contact with the wall 313 of the first base member 3, and a mounting portion 271 of the second base member 5 is mountd on the first flange 314 of the first base member 3. Each of the pair of pawls 521 of the second base member 5 engages with each of the pair of holes 317 of the first base member 3. The step of the second base member 5 is defined within a rear portion of the second base member 5, and the step of the second base member 5 includes a first horizontal plate 522 and a vertical surface 523. The first horizontal plate 522 of the second base member 5 is inserted into the space defined between the main plate 311 and the clamping tabs 315, and the vertical surface 523 of the second base member 5 is in contact with the clamping tabs 315 of the first base members 3. The third embodiment also facilitates installation of the rear view mirror assembly.

A fourth embodiment of a rear view mirror assembly is shown in Figure 13. The fourth embodiment is similar to the first embodiment disclosed in Figure 2. However, the fourth embodiment has several differences disclosed hereunder.

The first base member 3 is cemented to a windshield 1 by an adhesive 2. The first base member 3 is made of rolled stainless steel so that a contact surface of the first base member 3 does not have any pores thereon. In addition, the first base member 3 has a similar coefficient of thermal expansion as the coefficient of thermal expansion for the windshield 1. Thus, air does not exist between the contact surface and the windshield 1 so that air passages are not formed. Further, the first base member 3 and the windshield 1 will expand at the same approximate rate when heated by the sun.

A bolt 38 engages with a cap 10 and extends downwardly from the spring 9. A mounting member 33 includes a third ball portion 32 at a lower surface thereof, and a fourth aperture 34 therein. The fourth aperture 34 is opened in the third ball portion 32, and the bolt 38 is inserted into the fourth aperture 34. A diameter of the fourth aperture 34 is slightly longer than a diameter of the bolt 38. The third ball portion 32 of the mounting member 33 is formed in a semi-spherical convex shape.

A support arm 15 includes an end 35 and an opposite end. The end 35 of the support arm 15 includes an outer surface and an inner surface thereof. A third socket portion 351 is formed on the outer surface of the support arm 15, and the third socket portion 351 is slidably mounted on the third ball portion 32 of the mounting member 33. The third socket portion 351 of the support arm 15 is formed in a semi-spherical socket concave shape, and a fifth aperture 37 is opened in the third socket portion 351 of the support arm 15. A diameter of the fifth aperture 37 of the support arm 15 is longer than the diameter of the fourth aperture 34 of the mounting member 33, and the bolt 38 is inserted into the fifth aperture 37 of the support arm 15. A fourth ball portion 352 is formed on the inner surface of the support arm 15, and the fourth ball portion 352 of the support arm 15 is formed in a semi-spherical convex shape. The fifth aperture 37 is opened in the fourth ball portion 352 of the support arm 15.

A fourth socket member 40 is mounted on the fourth ball portion 352 of the support arm 15, and the fourth socket member 40 includes an upper semi-spherical concave surface 401 and an inner peripheral edgethereof. The inner peripheral edge defines a sixth aperture 402 which is opened in the upper semi-spherical concave surface 401 thereof. A diameter of the sixth aperture 402 of the fourth socket member 40 is slightly longer than the diameter of the bolt 38, and the bolt 38 is inserted into the sixth aperture 402 of the fourth socket member 40.

The fourth socket member 40 includes a second protrusion 42 on the upper semi-spherical concave surface 401 thereof, and the second protrusion 42 is disposed around the sixth aperture 402 of the fourth socket member 40. The second protrusion 42 is formed in a trapezoid shape. The second protrusion 42 of the fourth socket member 40 is normally disposed into the fifth aperture 37 of the support arm 15, and the second protrusion 42 includes an inclined side and a semi-spherical concave surface thereof. An outer peripheral edge of the second protrusion 42 is rounded off. The inclined side of the second protrusion 42 is in contact with the inner peripheral edge of the support arm 15.

Therefore, the second protrusion 42 of the fourth socket member 40 temporarily prevents the support arm 15 from rotating about a central point 17 of the support arm 15. However, the fourth ball portion 352 of the support arm 15 can rise on the second protrusion 42 of the fourth socket member 40 by way of the inclined side and the round outer peripheral edge of the second protrusion 42, when a force "F₁" is applied on the support arm 15. A nut 41 is disposed under the fourth socket member 40 and the nut 41 engages with the bolt 38. Therefore, the nut 41 can support the fourth socket member 40, the support arm 15 and the mounting member 33 on the hook 6 of the second base member 5 through the bolt 38 and the spring 9.

A first unit of the rear view mirror assembly of the fourth embodiment includes the second base member 5, the spring 9, the fourth socket member 40, the support arm 15, the mounting member 33 and the bolt 38. The first unit of the fourth embodiment united by the bolt 38, so that it is easy for a worker to install the first unit of the fourth embodiment on the first base member 9. Accordingly it is not necessary for a worker to install components of the rear view mirror assembly on the windshield 1 piece by piece.

As described herein, the present invention overcomes the shortcomings of the known art by providing a first unit of the rear view mirror assembly enables a worker to install easily components of the rear view mirror assembly on a windshield or body member of a vehicle.