GB1591926A

GB1591926A - Rear view mirror assembly

Info

Publication number: GB1591926A
Application number: GB4935877A
Authority: GB
Original assignee: Britax Geco SA
Current assignee: SMR Automotive Systems France SA
Priority date: 1976-11-26
Filing date: 1977-11-28
Publication date: 1981-07-01
Also published as: DE2752818A1; FR2372054B1; DE2752818C2; JPS5924016B2; FR2372054A1; JPS53102544A; ES464466A1

Description

(54) REAR VIEW MIRROR ASSEMBLY (71) We, BRITIX (GECO) S.A., a French Company of 3 bis, Rue Leon Jost, 750117 Paris, France, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following statement: - The present invention relates to an exterior rearview mirror unit the casing of which can be oriented directly from inside the vehicle on which it is mounted.

The invention relates more particularly to an exterior safety rearview mirror unit the casing of which is adapted to be folded back along the body of the vehicle in the event of a shock.

Numerous rearview mirror units, having casings adapted to be folded back, are known in which adjustment is effected not by orienting the casing but by orienting the mirror itself by means of cables, levers, more or less complex linkages or else electrically.

Most of these rearview mirror units generally have complicated devices for controlling the orientation, and these are consequently fragile and expensive.

The object of at least the preferred embodiments of the invention is therefore to provide an exterior rearview mirror having a foldable casing, in which the adjustment device is simple and strong, and consequently reliable and economical, the control means for the rearview mirror unit being designed to pass into the window triangle, just above the door of the vehicle.

The invention provides a rear-view mirror unit having a casing adapted to be folded back in the event of a shock and adapted to be orientated from inside a vehicle, characterized in that the unit comprises first and a second U-shaped yokes, the branches of said yokes being articulated to each other for relative rotation about a first or folding axis, and the second yoke being adapted for articulation relative the vehicle to rotate about a second axis substantially perpendicular to said first or folding axis, means for transmitting the rotating movement of the first yoke, relative to the vehicle and about the first or folding axis, to the casing, the latter means enabling the casing to be released from the first yoke, in the event of a shock, so that the casing can pivot on the first or folding axis with respect to the first yoke, and means for independently controlling the rotations of the two yokes about their respective axes of articulation.

Embodiments of the invention will now be described with reference to the accompanying drawings, in which: Fig 1 is a perspective view of a mechanism for adjusting a rearview mirror casing, Fig 2 is a vertical section on the axis X-X1 of Fig 1, Fig 3 is a vertical section on the axis Y-Y1 of Fig 1, Fig 4 is a vertical section of part of another embodiment of the invention.

Fig. 5 is a vertical section on line A-A of Fig 4.

Fig 6 is a vertical section of part of another embodiment, Fig 7 is a horizontal section on the axis of a rod used in the device of Fig 6, Fig 8 is a view on line VIII-VIII of part of the structure of Fig 6.

As illustrated in Fig 1, a rear-view mirror unit according to one embodiment of the invention comprises a casing 1 containing the mirror holder and the mirror 2, the said casing being articulated on one side, by means of two parallel lateral fastening arms 3 and 4, about a substantially vertical folding axis Z-Z, embodied by two screws or bolts 5 and 6 situated in line with one another. Between the fastening arms 3 and 4 is disposed a first U-shaped yoke 7 of which the two branches 8 and 9 are articulated respectively about the two screws 5 and 6 and whose body 10 has an elongate opening 11 which extends longitudinally in a direction parallel to the axis Z-Zl. The casing 1, the yoke 7, and the screws 5 and 6 are supported by a second likewise Ushaped yoke 12, whose two parallel branches 13 and 14 straddle the fastening arms 3 and 4 of the casing and are also articulated about the two screws 5 and 6 constituting the axis Z-Z,. The body 15 of the yoke 12 is held against a support plate 16 fastened on the body 17 with the interposition between them of a protective sheet 18 of fibre, rubber, or plastics material. A substantially horizontal tubular control means 19 (Figure 2) passes through the plate 16, the sheet 18, and the body 17 of the vehicle and penetrates into the interior of the vehicle; the end of the said control means 19 which is situated outside the vehicle has a coaxial centring shoulder 20, while its other end, situated on the inside, is threaded and receives a nut 21 intended to be locked, the shoulder 20 and the nut 21 axially fastening the control means 19 in relation to the plate 16 and to the vehicle body 17, while enabling it to turn about its substantially horizontal axis X-X1, this rotation being controlled manually from inside the vehicle by means of a knurled button 22 screwed and locked on the threaded end of the control means 19.

The body 15 of the yoke 12 has a hole 23 serving to mount and center the said yoke on the coaxial shoulder 20, whose end face carries an eccentric stud 24 which is engaged in a substantially vertical hole 25 in a lever 26 articulated about a pin 27 fixed in the support plate 16, this pin 27 passing through a hole 28 in the form of an arc of a circle centred on the axis X-X, in the body 15 of the yoke 12 and being provided at its free end with a boss intended to hold the lever 26 applied against the body 15 of the yoke 12.

The lever 26 has the function of stepping down the force necessary for oscillating the yoke 12 about the axis X-X,, and its opposite end to that where the hole 25 is provided, in relation to its pivot pin 27, is engaged in an aperture 29 provided in the yoke 12. A rod 30 threaded at both ends is received and axially held in the tubular control means 19, through which it completely passes coaxially, the said road also passing through the knurled button 22 and extending to the interior of the vehicle where it receives a second knurled button 31 screwed on its end; on the other side of the rod 30 passes through a hole 32 in the shape of an arc of a circle which is provided in the lever 26 and centred on the pivot pin 27 of the said lever; the said rod extends between the two branches 8 and 9 of the yoke 7 and is held axially in the tubular control means 19, for example by means of circlips (not shown).

An operating nut or block 33 is screwed on that portion of the rod 30 which is situtated between the branches of the yoke 7, the said block having a lateral projection 34 whose free end is engaged in the hole 11 in the body of the yoke 7.

In the two contacting faces of the upper fastening leg 3 of the casing and of the upper branch 8 of the yoke 7 there are provided (Figure 3) sockets which are disposed opposite one another and in which balls 35 are accommodated, these balls defining a preferential orientation of the casing 1 in relation to the yoke 7, which in the normal position is disposed substantially vertically and parallel to the body 17 of the vehicle, the preferential orientation selected being that of the normal operating position of the rearview mirror unit, that is to say with the mirror directed rearwards and substantially perpendicular to the axis of displacement of the vehicle.

In order to maintain the engagement of the balls 35 in the cavities provided facing one another in the faces of the arm 3 and branch 8, these faces are held elastically in contact by means of Belleville washers 36 (Figures 2 and 3) compressed between the lower branch 9 of the yoke 7 and the lower fastening arm 4 of the casing, these washers pushing the yoke 7 back against the upper fastening leg 3 of the casing. The system thus achieved with the aid of the balls 35 and elastic washers 36 constitutes a snap engagement device which effects the rotational coupling, about the axis Z-Z1, of the casing 1 to the yoke 7, the snap engagement making it possible for them to be uncoupled in the event of a shock against the casing.

In normal use the rearview mirror unit according to the above embodiment of the invention functions in the following manner. If the user wishes to orientate the mirror of the rearview mirror unit in a substantially horizontal plane, all that he has to do is to turn the knurled button 31, the rotation of which brings about a displacement of the block 33 along the rod 30, the projection 34 of the said block, which is engaged in the hole 11 in the yoke 7, pivoting the latter about the substantially vertical axis Z-Z1. Because of the coupling by snap engagement the yoke 7 carries with it the casing 1 of the rearview mirror unit, which thus pivots about the said axis Z-Z,.

When the user turns the knurled button 22 and the associated tubular control means 19, the lever 26 pivots about its axis 27 under the action of the eccentric stud 24 engaged in the vertical hole 25, the rotation of the lever entailing the rotation with a stepdown action of the yoke 12, which pivots from front to rear about the axis X-X, and similarly pivots the casing of the rearview mirror unit.

It will be noted that the "left-right or "up-down" adjustments of the mirror are effected independently without interfering with one another because of the elongated dimension of the hole 11 which enables the yoke 7 to pivot about the axis X-X, without thereby entailing the rotation of the block 33; nevertheless, simple clearances would be sufficient because the rotation of the yoke 7 is of the order of some twenty degrees, which would entail only very slight axial displacement of the block 33 if it were driven rotationally.

Furthermore, the articulation of the casing 1 on the vehicle body and the adjustment mechanism according to the invention enable the said casing to fold back along the vehicle in the event of a shock. In fact, if the casing is subjected to a lateral shock which urges it to rotate about the axis Z-Z1, owing to the fact that the yoke 7 is held by the projection 34 on the block 33 the balls 35 will pass out of their sockets, pushing back the said yoke 7 downwards and thereby compressing the elastic washers 36, and since the fastening arm 3 of the casing is made free to rotate it will be able to be folded back along the vehicle body.

After the shock, the mirror is easily returned to its preferential orientation by re-engaging the balls 35 in their sockets, thus ensuring correct positioning.

Because of this snap engagement system the casing can be folded back completely without damaging or even displacing the yoke 7 or the adjustment block 33, and this can be done with full safety, since adjustment to the normal position is effected automatically.

Furthermore, the step-down actions provided by the nut-screw system and the lever 26 make it possible to adjust the orientation of the casing without effort, despite a certain clamping provided in the articulations, in such a manner as to prevent excessively free rotation of the casing and to prevent it from spontaneously getting out of adjustment under the action of vibrations originating from the vehicle; similarly, the folding-back force due to the wind acting on the casing is fairly high when the vehicle is moving rapidly, and the use of a screwnut system makes it possible to obtain a high step-down ratio by providing a fine screwthread on the screw 30 and in the block 33.

The articulations of the casing and also the mechanisms for adjusting the orientation of the latter are obviously protected by a bellows or sleeve of rubber or plastics material which proects them from weather and external dust.

The stepping-down of the "up-down" movement can be obtained otherwise than by means of a lever, for example by means of meshing gears or else by means of an epicyclic reduction gear unit accommodated in the large knurled button 22.

Figs. 4 and 5 show part of another embodiment with alternative means for adjusting the elevation of the casing 1, and hence the mirror 2, by rotating a knob 38. A second yoke 37, corresponding with yoke 12 of Fig. 1, rotates about axis X-X1 when knob 38 is turned. Knob 38 is splined on a tubular member 39 through which a stem or rod 40 passes for the azimuthal adjustment, or control of the orientation of the casing 1 and mirror 2 in a substanatially horizontal plane. However, the means for effecting such azimuthal adjustment is not shown in detail as it corresponds with the respective means for such adjustment in the embodiments of Figs. 1-3.

Tubular member 39 is freely rotatable within a tubular extension 37a of yoke 37, the extension being rotatable in a fixed bearing 41. The end of member 39, remote from knob 38, is provided with an eccentric 42 formed by a disc located in a circular slot 43 in a lever 44. At one end of lever 44 a slot 45 receives a pin 46 which is attached to bearing 41. A slot 47, at the other end of lever 44, receives a pin 48 which is attached to yoke 37. This enables relative sliding movement between the respective pins and slots 45, 46 and 47, 48.

Rotation of knob 38 in one direction or the other causes corresponding rotation of eccentric 42 and of lever 44 about the fixed pin 46. As pin 48 is received in slot 47, yoke 37 thereby rotates about the axis X-X1. As the angle of rotation of lever 44 is much less than the corresponding angle of rotation of eccentric 42, precise adjustment of the position of lever 44 is possible by rotation of knob 38. Such a reduction drive is also advantageous with regard to areodynamic effects or pressures on the casing or rear member (which may be large and/or assymmetrical) attached to the frame 1 of the mirror head. Such effects create an additional torque which must be overcome, or resisted, with regard to the elevational position, ol axis of adjustment, of frame 1 and hence mirror 2. Moreover, the reduction drives reduces, or avoids the possibility of breakage of the driving components which may be small and made out of materials with a low breaking strength.

Thus, the reduction drive does not enable reversal of an adjusted position and it is a simple and cheap mechanism which enables a reduction in the mechanical clearance between the driving members.

Figs. 6-8 show part of another embodiment with alternative means for adjusting the elevation of casing 1 and hence mirror 2. A second yoke 50, corresponding with yoke 12 of Fig. 1, is rotatable about a barrel 51 which is fixed to the body 52 of a car by means of a nut 53, which tightens body 52 against a shoulder 54 of barrel 51.

Yoke 50 has an inwardly directed edge 55 which is slidable in a circular groove 56 defined by a flanged end of barrel 51 and the edges of a hole in the car body 52 which receives the barrel 51. A resilient seal, washer, or jointing member 57 is interposed between the body 52 and the yoke 50 has shown.

The barrel 51 has an axial and circular bore in which a stem 58 is freely rotatable for azimuthal adjustment or orientation of the mirror in a substantially horizontal plane. The barrel 51 includes a cylindrical extension 59 on which a knob 60 is freely rotatable, the knob being secured by a clip 61. Knob 60 has a thread 62 which cooperates with a toothed rack 63. As shown in Fig. 8, rack 63 is formed with an elongate body or tongue which is parallel with the longitudinal axis of stem 58 and which is slidably located in a passageway 64 in barrel 51. The elongate body of rack 63 has two projections 65, laterally disposed on each side thereof, which form two cams of which the operating or active faces 66 are substantially aligned and provided with appropriate surfaces. Faces 66 co-operate with projecting rims 67 on yoke 50.

Rotation, in one direction or the other, of knob 60, causes corresponding translational movement of the toothed rack 63, which causes rotation of yoke 50 about the axis of rod 58 due to one or the other of cams 65. Practically no clearance exists because cams 65 are substantially and continuously in contact with the co-operating rims 67 and because only a small angular displacement is involved (of for example +5 to 10 ). Such a drive is also irreversible and provides the important advantage of a reduction ratio between the movement of knob 60 and the movement of yoke 50.

WHAT WE CLAIM IS: - 1. A rear-view mirror unit having a casing adapted to be folded back in the event of a shock and adapted to be orientated from inside a vehicle, characterized in that the unit comprises first and second U-shaped yokes, the branches of said yokes being articulated to each other for relative rotation about a first or folding axis and the second yoke being adapted for articulation relative to the vehicle to rotate about a second axis substantially perpendicular to said folding axis, means for transmitting the rotating movement of the first yoke, relative to the vehicle and about the first or folding axis, to the casing, the latter means enabling the casting to be released from the first yoke, in the event of a shock, so that the casing can pivot on the first or folding axis with respect to the first yoke, and means for independently controlling the rotations of the two yokes about their respective axes of articulation.

2. A mirror unit according to claim 1, characterized in that the means for controlling the rotation of the second yoke comprises a tubular element mounted coaxially to the axis of articulation of the second yoke, and means for rotationally coupling the tubular element to the second yoke.

3. A mirror unit according to claim 2, characterized in that the means for rotationally coupling the tubular element to the second yoke comprises a step-down lever.

4. A mirror unit according to claim 2, characterized in that the means for rotationally coupling the tubular element to the second yoke comprises a train of stepdown gears.

5. A mirror unit according to claim 3, characterized in that said step down lever is hinged on a fixed axis parallel with the axis of said tubular element and is driven rotatably by way of an eccentric integral with said tubular element, one end of said lever being provided with an elongate slot in which a pin integral with said second yoke can slide.

6. A mirror unit according to claim 2, characterized in that said means for rotationally coupling said tubular element to said second yoke comprises a thread provided on said tubular element, a toothedrack cooperating with said thread and moveable in translation in a parallel direction to the axis of the tubular element, guiding means for guiding said toothed-rack and cam means integral with the toothedrack cooperating with appropriate abutment surfaces integral with said second yoke in order to rotate said yoke in one direction or the other according to the translating direction of said toothed-rack.

7. A mirror unit according to claim 6, characterized in that said cam means comprises two cams disposed on each side of said toothed-rack the active faces of said cams being aligned.

8. A mirror unit according to claim 7, characterized in that said active faces of the two cams are both continuously in contact with appropriate rims provided on the second yoke.

9. A mirror unit according to any one of the preceding claims, characterized in that the means for controlling the rotation of the first yoke comprises a screw-nut system in which the screw is provided for passage from the exterior to the interior of the vehicle and a nut carries a projection engaged in a substantially vertical hole provided in the yoke body connecting the two

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. car by means of a nut 53, which tightens body 52 against a shoulder 54 of barrel 51. Yoke 50 has an inwardly directed edge 55 which is slidable in a circular groove 56 defined by a flanged end of barrel 51 and the edges of a hole in the car body 52 which receives the barrel 51. A resilient seal, washer, or jointing member 57 is interposed between the body 52 and the yoke 50 has shown. The barrel 51 has an axial and circular bore in which a stem 58 is freely rotatable for azimuthal adjustment or orientation of the mirror in a substantially horizontal plane. The barrel 51 includes a cylindrical extension 59 on which a knob 60 is freely rotatable, the knob being secured by a clip 61. Knob 60 has a thread 62 which cooperates with a toothed rack 63. As shown in Fig. 8, rack 63 is formed with an elongate body or tongue which is parallel with the longitudinal axis of stem 58 and which is slidably located in a passageway 64 in barrel 51. The elongate body of rack 63 has two projections 65, laterally disposed on each side thereof, which form two cams of which the operating or active faces 66 are substantially aligned and provided with appropriate surfaces. Faces 66 co-operate with projecting rims 67 on yoke 50. Rotation, in one direction or the other, of knob 60, causes corresponding translational movement of the toothed rack 63, which causes rotation of yoke 50 about the axis of rod 58 due to one or the other of cams 65. Practically no clearance exists because cams 65 are substantially and continuously in contact with the co-operating rims 67 and because only a small angular displacement is involved (of for example +5 to 10 ). Such a drive is also irreversible and provides the important advantage of a reduction ratio between the movement of knob 60 and the movement of yoke 50. WHAT WE CLAIM IS: -

1. A rear-view mirror unit having a casing adapted to be folded back in the event of a shock and adapted to be orientated from inside a vehicle, characterized in that the unit comprises first and second U-shaped yokes, the branches of said yokes being articulated to each other for relative rotation about a first or folding axis and the second yoke being adapted for articulation relative to the vehicle to rotate about a second axis substantially perpendicular to said folding axis, means for transmitting the rotating movement of the first yoke, relative to the vehicle and about the first or folding axis, to the casing, the latter means enabling the casting to be released from the first yoke, in the event of a shock, so that the casing can pivot on the first or folding axis with respect to the first yoke, and means for independently controlling the rotations of the two yokes about their respective axes of articulation.

branches of the yoke.

10. A mirror unit according to any one of the preceding claims, characterized in that the means for transmitting the rotating movement of the first yoke about the folding axis to the casing comprises a ball snap engagement device.

11. A mirror unit according to claim 10, characterized in that the casing has two parallel lateral fastening arms arranged to straddle the opposite branches of the first yoke, the mutually facing faces of a fastening arm and of an adjacent branch of said yoke being provided with sockets disposed opposite one another in such a manner as to accommodate partially a ball, resilient means being provided to push the said faces towards one another.

12. A rear-view mirror unit substantially as herein described with reference to Figs 1-3 of the accompanying drawings.

13. A rearview mirror unit substantially as herein described with reference to Figs 4 and 5 of the accompanying drawing.

14. A rear-view mirror unit substantially as herein described with reference to Figs 6-8 of the accompanying drawings.