GB2237252A

GB2237252A - An external rear view mirror for a vehicle

Info

Publication number: GB2237252A
Application number: GB9019763A
Authority: GB
Inventors: Elio Lupo
Original assignee: Gilardini SpA
Current assignee: Marelli Europe SpA
Priority date: 1989-09-22
Filing date: 1990-09-10
Publication date: 1991-05-01
Anticipated expiration: 2010-09-10
Also published as: GB9019763D0; IT8953361V0; ES1015194Y; GB2237252B; FR2652318A1; FR2652318B1; ES1015194U; DE4030010A1; IT217190Z2

Abstract

A rear view mirror for a motor vehicle, provided with an outer body housing a reflecting sheet and carrying a support casing (10) for a transmission device (13) driven by an electric motor (15) and adapted to cause turning motion of the outer body about a fixed shaft (26), and including positioning means (66, 72) adapted to define a predetermined stable angular position of the outer body with respect to the motor vehicle body, which acts in a substantially radial direction with respect to the said axis of rotation (26) and includes a cylindrical body (66) guided in a frame (67) fixed to this casing (10) and thrust by a spring (65) against the lateral surface of an annular body (35) fixed for rotation with the said shaft (26), on which there is formed a seat (72) adapted partially to house the cylindrical body (66) to define this stable angular position. <IMAGE>

Description

1 AN EXTERNAL REAR VIEW MIRROR FOR A VEHICLE The present invention relates

to an external rear view mirror for a motor vehicle., in which there is provided 5 electric drive for displacement between a normal use 1 position and a position folded alongside the motor vehicle body.

Known motor vehicle external rear view mirrors of the said type comprise an outer body housing a reflecting sheet, and means for fixing this outer body to a motor vehicle body adapted to permit a rotation of the body with respect to the vehicle body about a substantially vertical axis in such a way as to allow the outer mirror body to be folded back, at least rearwardly, and in which this rotation is driven by an electric motor actuable from the interior of the motor vehicle. Mechanisms designed to allow this displacement of the outer body of the mirror must, as well as allowing the electrical control movement, also allow a displacement of the body itself solely by mechanical action, for reasons of safety in the event of knocks etc. Moreover it is desirable that the normal use position assumed by the outer body of the mirror, substantially perpendicular to the side of the vehicle, is always the same even after repeated displacement movements of the outer body of the mirror itself. Known devices which achieve the said function do not however sufficiently satisfy this requirement in that either to guarantee the possibility of the mechanical safety function they are rather complex and therefore expensive, or else, if of more simplified form, do not guarantee over a period of time sufficient repeatability of the normal use position assumed by the outer body of the mirror.

The object of the present invention is to provide a rear view mirror for a motor vehicle, of the type-in which displacement of the outer body with respect to the motor vehicle body is electrically driven, which resolves the said disadvantages connected with electrical rear view mirrors of known type, that is to say which will be of relatively simple and therefore economic construction whilst guaranteeing to be fully operational even as far as the mechanical action alone is concerned, and in which the mirror assumes its operating position with a high defence of constancy and repeatability.

The said object is achieved by the present invention in that it relates to an external rear view mirror for a motor vehicle, of the type comprising an outer body, a reflecting sheet housed in the said outer body, means for fixing a said outer body to a motor vehicle body, the said the said outer body fixing means permitting a rotation of with respect to the said motor vehicle body about a substantially vertical axis, reversible motor means housed 1 p in the said outer body, transmission means angularly coupling the said motor means and the said fixing means to produce the said rotation about the said axis and supply and control means for the said motor means, characterised by the fact that the said fixing means include positioning means adapted to define at least one predetermined stable angular position of the said outer body with respect to the said motor vehicle body, the said positioning means acting in a substantially radial direction with respect to the said axis of rotation.

For a better understanding of the present invention a preferred embodiment is hereinafter described purely by way of non-limitative example and with reference to the attached drawings, in which:

Figure 1 is a longitudinal section of an external rear view mirror for a motor vehicle formed according to the principles of the present invention:

Figure 2 is a front view of various details of Figure 1:

Figure 3 is a partially sectioned view taken on the line III-III of several details of Figure 2:

Figure 4 is an exploded front perspective view showing various details of Figure 2: and Figure 5 is an exploded view from above of the details shown in broken outline in Figure 4.

Referring to Figures 1 and 2, the reference numeral 1 generally indicates an external rear view mirror for a motor vehicle. The mirror 1 includes an outer hollow rectangular body 2, in which are housed a reflecting sheet 3 facing a rear aperture 4 of the body 2 and fixed to associated support and orientation means 5 which include a support plate 6 fixed to the outer casing by projections 7 of the body 2, on which is fixed a device 8 for adjustment of the position of the reflecting sheet 3, for example, of the type described in the industrial utility model entitled: "external rear view mirror for vehicles" filed 22 May 1987 by the same applicant, or of any other conventional type. To the support plate 6 there is further connected, by means of screws not illustrated, a fixing bracket 9 for a casing 10 made in two half shells of plastics material, which houses a device 13 adapted to cause a rotation of the casing 10 with respect to a support arm 14, partially illustrated, and adapted to be fixed to a motor vehicle body 19 of the motor vehicle, indicated in broken outline.

The device 13 includes a reversible electric motor 15 having a horizontal axis, a shaft 16 of which carries a pinion 17 which transmits drive to a speed reduction gear 18. This reduction gear 18 includes a drive spindle 19 which carries a pair of toothed wheels 20, 21. The wheel 20, of large diameter, meshes with the pinion 17: the 1 wheel 21, of small diameter, meshes with a wheel 22 fixed angularly to a shaft 23 parallel to the shafts 16 and 19 and having a portion 24 formed with a worm screw which engages, by means of a safety coupling 25, a shaft 26 having a vertical axis, fixed to the arm 14 bymeans of a prismatic coupling 27 between corresponding portions of the shaft 26 and the arm 14 towards the lower end of the shaft 26 itselft the terminal portion of which is threaded and on which is screwed an axial locking nut 60.

The casing 10 is provided with a pair of respectively upper and lower apertures 28, 29 for passage of the shaft 26. The casing 10 is further supported in an axial sense with respect to the arm 14 by a thrust bearing 31 in the form of a ball bearing mounted with radial clearance on the shaft 26.

The coupling 25 is constituted by a pair of rings 34, 35 mounted on the shaft 26. The ring 34 is provided with external helical gear teeth which mesh with the worm screw 24, and is freely rotatable on the shaft 26. The ring 35 is coupled for rotation with the shaft 26, but is slidable with respect to it in an axial sense. by means of an internal annular surface with two opposite flat portions 36 which engage respective longitudinal flat portions 37 of the shaft 26. The rings 34 and 35 are angularly coupled together by means of frontal projections 38 of the ring 35 of semi-cylindrical form (Figure 4) with radial axes, equally spaced by 900, which engage respective cavities 39 of corresponding form in the ring 34. In an annular groove 58 of the shaft 26 is mounted a resilient ring or circlip 40 which functions as an upper axial stop fo'r the ring 35: the rings 34, 35, normally in engagement with one another, are maintained in axial contact against this ring 40 by a coil spring 43 wound around the shaft 26 and compressed between the ring 34 and a washer 44 lying within the casing 10 around the lower aperture 29.

On a lateral portion 61 of the casing 10 there is fixed, by means of screws 62, a body 63 which has a cavity 64 for housing a coil spring 65 the other end of which rests on a small cylinder 66 which is partially disposed within a guide body 67, conveniently made of anti-friction plastics material, which is locked by the body 63 itself within an aperture 70 of the lateral portion 61 of the casing 10. This small cylinder 66 rests therefore on the lateral surface of the ring 35, which has a seat 72 at a predetermined angular position defined by two projections 73 of curved profile, with an interposed surface portion 75 which has a radius greater than the radius of the lateral surface of the ring 35 itself '(Figure 3).

On the upper portion of the shaft 26 there is fixed, by means of a grub screw 80, an annular body 81 which carries 1 beneath it a pair of sliding blade electrical contacts 82 and 83, which cooperate with the tracks of a corresponding printed circuit 85 which is fixed on the casing 10 around the upper aperture 28, and which is connected with cables 87 to a control circuit substantially of known type for electrical supply to the motor 15.

The operation of the rear view mirror of the present invention as described is as follows.

Starting from a normal functioning configuration of the mirror 1, that is to say with the body 2 substantially at 900 with respect to the side 90 of the motor vehicle, as is illustrated in Figure 1, when the user desires to bring the body 2 into the completely folded position, he actuates a control key of the control circuit which gives rise to electrical supply to the motor 15 the rotation of which is transmitted by the pairs of toothed wheels 17-20 and 21-22 to the worm screw 24. This crew is in mesh with the ring 34 which, in normal conditions, is fixed in that it is coupled to the shaft 26 by the frontal coupling with the ring 35. Therefore, rotation of the screw 24 produces a rotary motion of the entire gear reduction device 18, the casing 10 and consequently the body 2 of the mirror 1 about the shaft 26 until the tracks of the printed circuit 85, which rotate with the casing 10, are carried to a position, with respect to the contact blades 82 and 83, such that there is a disconnection of the feed to the motor 15, and then the body 2 of the mirror 1 stops in the position completely folded back towards the side of the vehicle. Upon commencement of the movement of the casing 10 the small cylinder 66 is displaced beyond the projection 73 and therefore slides on the lateral surface of the ring 35 which has a smaller radius than that of the seat 72 so as to reduce the resilient thrust of the spring 65 and therefore the force of actuation of the motor 15.

When the user desires to return the mirror 1 into the normal operating configuration, that is to say with the body 2 substantially at 900 with respect to the side 90 of the motor vehicle, he actuates another control key on the control circuit, which gives rise to electrical supply in the opposite sense to the motor 15 by means of the printed circuit 85 which was in fact stopped in a new contact position with the blades 82 and 83: by this the screw 24 causes a rotary movement of the entire gear reduction device 18, the casing 10, and consequently the body 2 of the mirror 1 about the shaft 26 in the opposite sense from the preceding rotation until the tracks of the printed circuit 85 are carried into a position, with respect to the contact blades 82 and 83, such that the motor 15 is again disconnected from the supply, and therefore the body 2 of the mirror 1 stops in the position perpendicular to the side of the body. Correspondingly, at the end of the movement of the casing 10, the small cylinder 66 is 1 - 9 1 displaced beyond the projection 73, into the seat 72 which gives a very precise and constant angular reference position for the body 2 with respect to the arm 14 under the action of the spring 65.

1.

On the other hand, if the body 2 is manually or accidentally folded back, for example in the case of an impact, there is a turning movement of the whole of the body 2 and consequently of the casing 10, the entire gear reduction device 18, the screw 24 and the ring 34 about the shaft 26, which causes an angular disengagement between the ring 34 and the ring 35 thanks to the particular form of the teeth 38 and the corresponding seats 39, with downward displacement of the ring 34 against the action of the spring 43. Correspondingly the small cylinder 66 is displaced from the seat 72 and slides on the lateral surface of the ring 34 as already described.

The return of the mirror 1 into the normal use position can take place with opposite mechanical action from that now described, or with electrical actuation as previously described in detail, until the small cylinder 66 has reengaged in the positioning seat 72.

From a study of the characteristics of the mirror 1 formed according to the present invention the advantages which it allows are evident. In fact, with a relatively simple and therefore economical structure it is possible to have electrical movement and also safety mechanical movement, by means of the utilisation of the same ring 34 as a functional element for the two types of movement, both with respect to the small cylinder 66 and with respect to the ring 34: moreover, the achievement of a precise and constant predetermined angular reference position for the body 2 with respect to the arm 14, by means of an element urged radially towards the shaft 26 defining the axis of rotation, constituted by the small cylinder 66 which is housed in the seat 72 formed on the ring 35, offers characteristics of effectiveness and simplicity, thanks also to the spring 65 which allows compensation of any play. The use of the small cylinder 66 as the cooperating element for angular positioning of the mirror, which during movement of the mirror 1 can thus rotate on the lateral surface of the ring 35, thereby reducing the actuating force of the motor 15, is also advantageous.

Finally, it is clear that the mirror 1 described hereinabove can have modifications and variations introduced thereto both to the configuration and arrangement of the various parts, without by this departing from the protective ambit of the present invention.

Claims

1. An external rear view mirror (1) for a vehicle, of the type comprising an outer body (2), a reflecting sheet (3) housed in the said outer body (2), means (14,26) for fixing the said outer body (2) to a motor vehicle body (90), the said fixing means (14,26) permitting a rotation of the said outer body (2) with respect to the said motor vehicle body (90) about a substantially vertical axis 10 (26), reversible motor means (15) housed in the'said outer body (2), transmission means (13) angularly coupling the said motor means (15) to the said fixing means (14,26) to produce the said rotation about the said axis (26) and supply and control means (81,85) for the said motor means 15 (15), characterised by the fact that the said fixing means (14,26) includes positioning means (66,72) adapted to define at least one predetermined stable angular position of the said outer body (2) with respect to the said motor vehicle body (90), the said positioning means (66,72) 20 acting in a substantially radial direction with respect to the said axis of rotation (26).

2. A rear view mirror according the Claim 1, characterised by the fact that the said positioning means 25 (66,72) include resilient actuation means (65) interposed between the said outer body (2) and the said axis of rotation (26).

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3. A rear view mirror according to Claim 2, characterised by the fact that the said positioning means (66,72), include a first body (66) guided in a frame (67) fixed with respect to the said outer body (2), and thrust by a spring (65) against the lateral surface of a second body (35) angularly fixed to the said axis of rotation (26), the said second body (35) having at least one seat (72) adapted to house the said first body (66) at least partially, to define the said stable angular position of the said outer body (2) with respect to the said motor vehicle body (90).

4. A rea3 view mirror according to Claim 3, characterised by the fact that the said transmission means (13), under the action of the said motor means (15), effect an angular displacement of the said first body (66) with respect to the said second body (35).

5. A rear view mirror according to Claim 4, characterised by the fact that the said first body (66) has a rolling surface for rolling on the said second body (35).

6. A rear view mirror according to Claim 4 or Claim 5, characterised by the fact that the said second body (35) has a lateral surface with the smaller radius than that of the said seat (72) for housing the said first body (66).

1 i z c

7. A rear view mirror according to any of claims from 4 to 6, characterised by the fact that the said seat (72) for housing the said first body (66) is separated from the lateral surface of the said second body (35) by means of 5 two projections (73).

8. A rear view mirror according to any of Claims from 3 to 7, characterised by the fact that the said fixing means (14,26) includes a support arm 14 adapted to be fixed to the said motor vehicle body (90) and a shaft (26) angularly fixed to the said arm (14) and having as its axis the said axis of rotation of the said outer body (2), the said transmission means (13) including speed reduction means (18) and a safety coupling (25) adapted to disconnect the said speed reduction means (18) from the said shaft (26) when the couple transmitted by the said safety coupling (25) exceeds a predetermined value, the said safety coupling (25) including a first ring (35) mounted freely rotatably on the said shaft (26) and provided with external gear teeth which engage the said reduction gear means (18), and a second ring (35) comprising the said second body: the said rings (34,35) being maintained in axial contact with one another by resilient means (43), and being coupled together for rotation by frontal engagement means (38,39).

9. A rear view mirror according to Claim 8, characterised 4 14 - by the fact that the said engagement means (38,39) include a plurality of angularly spaced semi-cylindrical projections (39) having radial axes carried by one of the said rings (35) and adapted to engage respective cavities (39) of corresponding shape formed on the other (34) of the said rings (34,35).

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10. A rear view mirror according to any preceding claim, characterised by the fact that the said supply and control means for the said motor means (15) include a'printed circuit (85) and contact blades (82,83) respectively fixed to the said outer body (2) and to the said axis of rotation (26).

11. An external rear view mirror for a vehicle, substantially as described with reference to the attached drawings.

1:

Published 1991 atMe Patent Ofrice. State House, 66/71 High Holborn. London WCIR47P. Further copies may be obtained from Saks Branch, Unit 6. Nine Mile Point Cwmiclinfach. Cross Keys. Newport, NPI 7HZ. Printed by Multiplex techniques lid. St Mary Cray, Kent.