External rear view mirror for motor vehicles

A rear view mirror which can be extended and retracted laterally in a vertical plane, with respect to the body of a commercial vehicle, by means of an arm structure comprising an expandable polygonal linkage which interconnects a mirror body with a rotatable part of an articulated support fixed to the vehicle; the linkage having pivots formed by bolts which can be tightened to lock the mirror in an adjusted setting.

The present invention relates to external rearview mirrors for motor 
caravans, commercial vehicles and the like, particularly those in which 
that part of the vehicle body behind the driver's cab is wider than the 
cab. 
More particularly, the invention is concerned with rear-view mirrors of the 
type comprising a mirror body by which a reflective element is adjustably 
supported, an articulated support having a fixed part adapted to be fixed 
to a side of a vehicle body, and a rotatable part, and an arm structure 
which interconnects the rotatable part of the support and a side of the 
mirror body to support the latter in a projecting manner with respect to 
the vehicle body; the rotatable part of the support being pivoted, with 
respect to the fixed part, about an axis which, in the mounted position of 
the mirror on the vehicle, is substantially vertical so as to enable an 
angular movement of the mirror body and the arm structure between a 
laterally extended position projecting laterally outwardly with respect to 
the vehicle body and a retracted position against the body. 
The object of the present invention is to provide a rear-view mirror of the 
aforesaid type in which: 
(1) the arm structure is of sufficient length to support the reflecting 
element in a projecting manner from the side of the driver's cab in such a 
way that the reflecting element projects beyond the widest part of the 
vehicle body behind the cab; 
(2) the arm structure enables the adjustment of both the height and the 
lateral distance of the reflecting element with respect to the driver's 
cab; 
(3) the arm structure enables the mirror body and the reflecting element to 
be drawn near to the cab, not only by means of the said angular movement 
around the vertical pivot axis of the articulated support, but also by 
means of a movement of the mirror body and the reflecting element in a 
substantially vertical plane, transversely with respect to the vehicle, 
which causes it to be retracted within the profile of the body behind the 
cab, thus, enabling the vehicle to have access to narrow passages. 
According to the present invention there is provided a rear-view mirror of 
the aforesaid type in which the arm structure comprises a linkage having 
pivot axes which, in the mounted position on the vehicle, are 
substantially horizontal, said linkage forming a polygon which is 
expandable at least between an extended position, in which the mirror body 
is at a maximum distance from the support and a retracted position in 
which, in the mounted position on the vehicle, the mirror body is raised 
and drawn near the vehicle body, the linkage being provided with 
releasable locking means for selectively preventing and permitting the 
expansion of said linkage. 
Thus, the mirror body with its reflecting element may be raised and lowered 
at will by means of the expandable linkage which can be locked in the 
desired position.

FIG. 1 shows a motor vehicle, for example, a delivery van or motor caravan, 
having a driver's cab A and a body B of larger width than the cab A. The 
body B may comprise, for example, a box structure in the case of a 
delivery van, or an accommodation unit in the case of a motor caravan. 
On one side of the bodywork of the cab A an external rear view mirror 
assembly, generally indicated S, is mounted. The mirror assembly S has a 
shell-like body 10, open on a rearwardly-facing side, made, for example, 
of plastics material or light alloy. the body 10 forms a mount for a 
reflective element 12 comprising a plane or slightly convex mirror. 
As shown in FIG. 3, the reflective element 12 is fixed, for example, by 
means of adhesive, to a backing plate 14 which has in its centre a boss 16 
formed internally with a spherical socket 18. A part-spherical ball or 
knee 20 is engaged in the socket 18 forming a ball-and-socket swivel 
joint. The knee 20 forms part of a support structure 22 situated in the 
cavity of body 10 and formed in one piece with the latter or inserted into 
and fixed to the body 10. 
As shown in FIGS. 2 and 4, the rear view mirror assembly S is provided with 
an articulated support, generally indicated 24, which has a fixed part 26 
and a rotatable part 28. The fixed part 26 has a mounting flange 30 with 
through holes 31 for fixing screws (not shown) by which the flange 30 can 
be fixed to the bodywork of the vehicle cab A. A bush 32 is formed 
integrally with the flange 30. The bush 32 provides a sealing for pivot 
pin 34 of the rotatable part 28. The hinge axis defined by the pivot pin 
34 is disposed substantially vertically in the mounted position of the 
mirror S on the vehicle cab. The pivot pin 34 has a head 36 provided with 
radial teeth which are maintained in engagement with corresponding radial 
teeth on the bush 32 by a spring 38, in known manner, so as to maintain 
the mirror assembly in an engaged position in which the assembly projects 
laterally outwardly from the side of the vehicle, while permitting the 
mirror assembly to fold inwards against the body of the cab A in the event 
of a collision, as required by safety regulations. By selective engagement 
of the teeth of the head 36 and the bush 32 the angle of the reflective 
element 12 can be adjusted in a substantially horizontal plane. 
The rotatable part 28 of the articulated support 24 has, in addition to the 
bolt 34 and the head 36, a bracket 40 provided with lower and upper 
articulation lugs 42, 44 (with reference to the mounted position of the 
assembly). 
A similar bracket 46 is fixed to one side of the body 10 of the mirror. The 
bracket 46 which has a base flange 48 for connection to the body 10 and a 
pair of spaced apart lower and upper articulation lugs 50, 52. The pairs 
of articulation lugs 42, 44 and 50, 52 define respective pivot axes which, 
in the installed position of the mirror assembly S on a vehicle, are 
substantially horizontal. 
the lower articulation lugs 42, 50 and the upper articulation lugs 44, 52 
are interconnected pair by pair by an arm structure formed by a linkage 
generally indicated 54. The linkage 54 has a first link 56 of considerable 
length, one end of which is articulated to the lower lug 42 by means of a 
bolt 58 and the other end of which is articulated to the lower lug 50 by 
means of a bolt 60. The linkage 54 has a second link 62, slightly shorter 
than the first link 56, one end of which is articulated to the upper lug 
44 by means of a bolt 64 and the other end of which is articulated by 
means of a bolt 66, to a short third link 68 which in turn is articulated 
to the upper lug 52 by means of a further bolt 70. 
The length of the third link 68 between its two pivot axes defined by the 
bolts 70 and 66, is of the same order of magnitude as the distance between 
the axis of the bolts 60 and 70. 
All the said bolts 58, 60, 64, 66 and 70 act as pivot pins and are provided 
with locking nuts (not referenced) and between the ends of the links and 
the corresponding lugs friction washers (not referenced) are interposed in 
a known manner. 
With the mirror assembly S in its extended position for use, as shown in 
FIGS. 2 and 4 and indicated by solid lines in FIGS. 1, the first link 56 
is substantially horizontal, whilst the second link 62 and the short third 
link 68 form between them a slightly obtuse angle with its vertex pointing 
downwards (FIG. 2). The linkage 54 may be maintained stably in this 
extended position by tightening at least one of its said articulation 
joints formed by the aforesaid bolts, which with their associated locking 
nuts form releasable locking means. 
Adjustment of the height of the reflective element 12 and therefore of the 
body 10 is effected by slackening the said locking means and then grasping 
the body 10 with the hand and moving it upwards or downwards, as shown in 
FIGS. 1 and 2. Upon such adjustment the body 10 performs a rotation about 
the pivot pin 60. At the same time, the second and third links 62 and 68 
rotate, the angle between these links increasing when the body 10 is 
rotated upwardly in the direction of the arrow F. The two links 56 and 62 
also rotate slightly upwards around their fixed pivot pins 58 and 64. The 
body 10 of the mirror may be fixed at any desired height by the tightening 
of at least one of the bolts forming the pivot pins. 
In order to retract the mirror body 10 completely within the dimensions of 
the projecting part of the vehicle body B, as shown in broken lines by 10a 
in FIG. 1, it is sufficient to continue the said upward rotation of the 
body in the direction of arrow F until the body 10 reaches the position 
shown in FIG. 5, in which the flange 48 is substantially horizontal and 
the linkage 54 is folded. It will be seen that the rotation of the two 
first and second links 56 and 62 about their pivot pins 58 and 64 is 
rather small (less than 10.degree.), and the overall length of the linkage 
54, in a transverse direction with respect to the pivot axes, has been 
little modified. 
Since the articulation of the linkage 54 entails only a slight modification 
of its overall length the entire assembly of the articulated support 24, 
the linkage 54 and the bracket 46 can be enclosed in a tubular dust-proof 
bellows, generally indicated 72, of rubber or flexible plastics material. 
The limited dimensional variation of the linkage 54 between the extended 
configuration shown in FIG. 2 and the retracted configuration shown in 
FIG. 5 enables the expansion and contraction of the bellows 72 to be kept 
within permissible limits. 
The flange 30 of the fixed part 26 of the articulated support 24 has a 
peripheral groove (not referenced), in which there is engaged resiliently 
an internal peripheral lip 74 formed at the corresponding end of the 
bellows 72. The other end of the bellows 72 has a similar internal 
peripheral lip 76 which is engaged resiliently in a similar external 
peripheral groove (not referenced) in the flange 48, thereby sealing the 
interior of the bellows 72. 
When it is desired to tighten or slacken one of the bolts forming the pivot 
pins of the linkage 54 one of the ends of bellows 72 is removed from the 
respective flange 30 or 48 and the bellows 72 contracted until the bolt in 
question is visible. Given the elasticity of the bellows 72, this 
operation does not present any difficulty and may be carried out rapidly.