GB2199001A

GB2199001A - Forward viewing device for vehicles

Info

Publication number: GB2199001A
Application number: GB08626279A
Authority: GB
Inventors: Clarke Antony Alexande Stanley
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-11-04
Filing date: 1986-11-04
Publication date: 1988-06-29
Anticipated expiration: 2006-11-04
Also published as: GB2199001B; GB8626279D0

Abstract

A viewing device for use on a vehicle comprises a housing 25 with an oblique, transparent front panel 27. Light from ahead of the vehicle passes through the transparent panel 27 to a convex first mirror 29, which reflects it onto a planar second mirror 32. The second mirror is adjustable in elevation at 34 and in azimuth at 30 to direct the light to the driver of the vehicle, who sees an image of the road ahead as from the position of the viewing device, assisting the driver to see past a vehicle in front of his own. <IMAGE>

Description

Forward viewing device for vehicles The invention relates to a device comprising two mirrors In which a user of a vehicle may view the road ahead from a viewpoint other than his own.

There have been numerous proposals of such devices, principally for the purpose of giving a driver who wishes to overtake another vehicle a view past that other vehicle of the road ahead. Such a device would be especially useful if mounted on, for example, the left-hand side of a British right-hand drive car that is to be driven in those countries where vehicles are driven on the right of the road. None of the previous proposals has achieved practical success, however, and it is an object of the present invention to provide a viewing device with which some of the drawbacks of previously proposed devices can be overcome.

The invention provides a viewing device for use on a vehicle comprising a housing, a first mirror mounted in the housing and a second mirror, the first mirror being so arranged in use to reflect light from a region in front of the device onto the second mirror and the second mirror being so arranged to reflect that light towards a user of the vehicle that the user can see an image of the said region in the second mirror, and a transparent plate so located as substantially to prevent air from flowing through the housing and impinging on the first mirror.

If flows of air, and especially the flows of air relative to the device caused by the forward motion of a vehicle to which the device is attached, are prevented from impinging on the first mirror (which must necessarily face forwards) , the first mirror is protected from becoming obscured by raindrops, dust, insects, and other airborne matter's covering its face.

The light path from the second mirror to the user may be at a high angle to the common plane of the light paths to and from the first mirror. The device may then be mounted roughly level with the driver's head both vertically and fore-and-aft, for example, outside one of the front doors of the vehicle, with the second mirror above or below the first mirror or above or below the light path forward of the first mirror, which assists in keeping down the width of the device.

Preferably, the second mirror is below and in front of the first mirror.

The transparent plate may be in front of the first mirror, where it provides direct protection for the first mirror against airborne matter of any sort, and is then advantageously at a low angle to the direction of the light path through it. The transparent plate may then form a front wall of the housing, but advantageously the housing extends forward of the transparent plate.

The device is preferably so arranged that when it is moving rapidly forwards there forms within the housing, between the open front of the housing and the transparent plate, a volume of air that is substantially at rest relative to the device. That volume of air can then prevent the surrounding air and any matter borne by it from entering the device without itself providing any solid surface on which such matter could be deposited to obscure the view through the device.

The second mirror may be mounted in the housing.

Instead, the second mirror, at least in an operating configuration of the device, may extend away from the housing, and is then advantageously so moveably mounted that it can be brought into an inoperative position against or inside the housing.

The invention also provides a viewing device for use on a vehicle comprising a first mirror arranged in use to reflect light from a region in front of the device onto a second mirror that is arranged in use to reflect that light to a user of the vehicle, wherein the normal at the centre of the first mirror is at approximately 270 to a notional axis such that a light ray travelling along it meets the centre of the first mirror and is reflected to the centre of the second mirror, and wherein the normal at the centre of the second mirror is at an angle of approximately 370 to a first plane containing the said axis and the centre of the second mirror, and at an angle of approximately 360 to a second plane containing the said.axis and perpendicular to the first plane.

The second mirror may be adjustably mounted so that when the device is in use on a vehicle the orientation of the second mirror can be varied without moving the device as a whole to enable the driver to view the image of the road ahead in the device from his usual driving position.

The first mirror may be convex, and advantageously has a radius of curvature of 2000 mm in the first plane and of 1500 mm perpendicular to that plane, and the second mirror may be flat. Each mirror may be approx irnately 125 rnrn wide.

It has been found that a device with those angles and dimensions gives a satisfactory image size when fitted to an ordinary motor car on the side further from the driver without requiring an unreasonably large device.

The invention further provides a mounting for attaching a device to the exterior of a vehicle in a position visible to a user of the vehicle, comprising a clamp arranged to engage an edge portion of a door of a vehicle that surrounds a window in the door, an arm attached to the clamp and arranged to lie generally parallel to the window extending from the clamp towards a central portion of the window, and means for attaching a device to the arm at a point remote from the clamp.

The device may then be mounted outside the window of one of the front doors of the vehicle without the need to drill holes in the car bodywork and without obstructing the opening and closing of the door or of the window.

The clamp may comprise a first jaw fixed to an end portion of- the arm, a second jaw mounted on the arm for sliding movement along the arm, and means for controlling the separation between the jaws. The means for controlling the separation between the jaws advantageously comprises screw-threaded means.

The length of the arm between the clamps and the attaching means may be adjustable which, together with the free choice that is available of the point at which to attach the clamp, allows the user to locate the device anywhere over a substantial area of the window.

The invention also provides a device with a mounting according to the invention. The attaching means may then comprise a ball on one of the device andthe arm, an externally screw-threaded projection on the other of the device and the arm, and an internally screw-threaded collar captive on the ball and arranged to screw onto the projection. The attaching means then also serves as a ball joint, allowing the orientation of the device to be adjusted, with a considerable economy of components and thus of manufacturing costs and complexity.

The invention also provides a vehicle fitted with a viewing device according to the invention.

Two forms of viewing device constructed in accordance with the invention will now be described by way of example only with reference to the accompanying drawings, in which: Fig. 1 is a sectional side elevation view of the device first form of; Fig. 2 is a front elevation view of the device, shown in Fig. 1; and Fig. 3 is a sectional top plan view of the second form of device.

Referring to Figs. 1 and 2 of the accompanying drawings, one form of viewing device comprises a housing indicated generally by the reference numeral 1 and having an upper portion 2 and a lower portion 3.

The housing is preferably moulded in a single piece from opaque plastics material.

The upper portion 2 of the housing 1 is generally rectangular as seen from the front and tapers from front to rear. The bottom wall 4 of the upper portion is substantially horizontal, as seen in Figs. 1 and 2, while the top wall 5 slopes down from front to back relative to the bottom wall. The right side wall 6 extends substantially parallel to the longitudinal direction, as seen in Fig. 2, while the left side wall 7 extends obliquely to that direction. As will become apparent, the planes of the walls 4 and 6 do not necessarily correspond to the horizontal and forward directions of a vehicle to which the device is attached.

The front end of the upper portion 2 is open, and the top wall 5 overhangs the bottom wall 4 slightly. The rear end of the upper portion 2 is closed by a rear wall 8 inside which is a first mirror 9 facing forwards and downwards. A flat plate of transparent material 10 extends the entire width of the upper portion 2 and slopes from the edge where the top wall 5 meets the rear wall 8 to meet the bottom wall 4 near its front edge. The transparent plate 10 is preferably a snap fit into a seating (not shown in detail) so that it can easily be removed for cleaning or to give access to the first mirror 9 if necessary.

The lower portion 3 of the housing 1 extends downwards from a rear portion of the upper portion 2, and that part of the bottom wall 4 of the upper portion that would lie between the upper and lower portions of the housing is omitted. As shown in Fig. 1, the bottom wall 4 is present only over about the front third of the length of the device. In the lower portion 3 is a second mirror 11 that faces upwards, rearwards, and to the right and is mounted on a ball-and-socket mounting 12 so that its orientation can be adjusted. The right side of the lower portion 3 is open, and an arm 13 attached to the mirror 11 projects from the housing.

The mirror 11 may be adjusted by moving the arm 13.

Instead of the ball-and-socket mounting 12 and/or the arm 13, other means may be provided for supporting and adjusting the second mirror 11. The second mirror 11 is so positioned that light entering the housing 1 through the open front end of the upper portion and falling on the first mirror 9 is reflected onto the second mirror.

On the right side wall 6 of the upper portion 2 is an externally-threaded projection 14 onto which is screwed a collar 15. The projection 14 and the collar 15 form the socket of a ball-and-socket joint the ball 16 of which can be clamped against rotation by tightening the collar onto the projection. The ball 16 is attached to an end portion of a first member 17 of a telescopic arm indicated generally by the reference numeral 18. A second member 19 of the telescopic arm 18 is slidably mounted on the first member 17 and can be locked against sliding by conventional means (not shown).

The second member 19 of the telescopic arm 18 carries a clamp indicated generally by the reference numeral 20, one jaw 21 of which is formed from an end portion of the second member. The other jaw 22 of the clamp 20 is slidably mounted on the second member 19 of the telescopic arm 18, and the separation between the two jaws is controlled by a screw 23 that can be rotated by means of a suitable tool (not shown). The first jaw 21 of the clamp 20 is shaped to engage the outside edge face of a door of a typical motor car, while the second jaw 22 engages the face surrounding a window opening on the outside of the glas. It will be appreciated that the clamp 20 shown in the drawings will not fit all motor cars, and a different clamp or other means of attaching the device may be used instead of the clamp 20 shown.

The device'is installed on a vehicle by positioning it outside the window of a front door of the vehicle, with the telescopic arm 19 and the right side wall 6 generally parallel to the window, and clamping the clamp 20 to the- portion of a door above or in front of the window. By a suitable selection of the point on the door at which the clamp 20 is atttached and the length of the telescopic arm 18, the device may be positioned at a desired position over a large part of the area of the window. The device is then aligned with the open front end of the upper portion 2 of the housing facing in a desired direction, and the ball-joint 14 to 16 is locked by tightening the collar 15.The driver of the vehicle then adjusts the second mirror 11, by moving the arm 13, so that when he is in his usual driving position he sees in the second mirror an image of the first mirror 9 and of the view through the open front end of the upper portion 2 of the housing 1.

In use, with the front end of the device facing fowards as the vehicle moves, the transparent plate 10 prevents air from flowing through the housing 1. As a result, a cushion of slightly compressed air forms in front of the transparent plate 10 inside and immediately in front of the housing. As a result, the airflow past the vehicle is deflected round the device, together with any airborne dust, spray, rain, insects or the like. Very little airborne matter enters the device, which continues to be usable even in heavy rain, and such as does enter the device is caught by the transparent plate 10, which is easily removed and cleaned, and does not reach the mirrors.

As an example of suitable dimensions for a device as shown in Figs. 1 and 2 intended to be mounted on the left side of a right-hand drive saloon car to afford a view forwards, the first mirror 9 may be 125 mm wide and 65 mm high, with an axis normal to the centre of its reflecting surface at an angle of 22.50 to the plane of the bottom wall 4 and substantially parallel to the plane of the right side wall 6. A meridian on the reflecting surface in a vertical plane containing that axis may have a radius of curvature of 2000 mm and a line on the reflecting surface in a plane containing that axis and perpendicular to that vertical plane may have a radius of curvature of 1500 mm.

The second mirror 11 may be flat and about the same size as the first mirror. A normal to the reflecting surfade of the second mirror may be angled at 360 to the plane of the bottom wall 4 and at 370 to the plane of the right side wall 6 although, as described above, the second mirror is to some extent adjustable. The second mirror may be rectangular or it may be tapered towards one end to make more efficient use of space.

The centres of. the two mirrors may be about 110 mm apart, on a line angled at 450 to the plane of the bottom wall 4. The bottom wall 4 and the top wall 5 of the upper portion 2 of the housing 1 may form an angle of about 40 between them, and the side walls 6 and 7 may form an angle of about So between them.

The device shown in Figs. 1 and 2 is not symmetrical, and the device may be a mirror image of that shown, for use on the right side of left-hand drive cars. Instead, or in addition, the device may be turned upside-down with respect to the position described above and mounted on the other side of the vehicle.

Although it is preferred to have the transparent plate 10 in front of the first mirror 9, it may instead be placed elsewhere in the device, for example, separating the upper portion 2 of the housing 1 from the lower portion 3 of the housing substantially in the plane of the bottom wall 4, provided that it still serves to prevent the flow of air through the housing.

With the transparent plate 10 in the position shown in Fig. 1, the top wall 5 and the parts of the side walls 6 and 7 above the plate may be omitted, giving a device that is more streamlined, both in appearance and in effect, but in which the transparent plate is more exposed to the weather and in which extraneous light can more easily enter the device.

The transparent panel 10 may then be formed in a single piece with the adjacent side walls 6 and 7.

Parts of the lower portion 3 of the housing 1 may be omitted, although the device may then not be as suitable for use in a position inverted with respect to that shown in Figs. 1 and 2, because there might then be insufficient protection from the weather.

Instead of, or in addition to, the arm 18's being telescopic the stud 14 may be movable, for example, slidable along a guide, relative to the housing 1.

Referring now to Fig. 3 of the drawings, the second form of device comprises a housing indicated generally by the reference numeral 25 that is generally in the shape of a triangular prism, with triangular top and bottom walls 26 that are horizontal, as seen in Fig. 3, and three sides that are vertical as seen in Fig. 3. The housing 25 is preferably moulded in one piece from opaque plastics material. One of the three sides, the right-hand side as shown in Fig. 3, extends substantially fore-and-aft and is open. A second side, facing forwards and to the left, is formed almost entirely by a transparent panel 27 fixed in the housing 25. The third side 28 has on its inside a first mirror 29.

At the front corner of the housing 25, where the first and second sides meet, is a vertical column 30 on which is pivotably mounted a door indicated generally by the reference numeral 31 that has within it a second mirror 32. The second mirror 32 is mounted, by means of brackets 33, on a rod 34 that extends the length of the door 31 and is supported by brackets 35 formed on the inside of the door and by a distal end wall 36 of the door. The rod 34 projects through the wall 36, and is retained and protected by a cap 37 that is secured in place by conventional means (not shown). The mirror 32 is pivotable with the rod 34 about the axis of the rod; its orientation may be adjusted by turning the cap 37 and it may be retained at a desired angle by friction between the bracket 35 and the rod 34 and/or by clamping means (not shown).

The door 31 is so dimensioned that it can be swung to a closed position in which it fills the open side of the housing 25, and may be provided with means for locking it in that closed position. It can be clamped at a desired angle when open by clamping means (not shown) incorporated in the column 30. The clamping means may comprise a screw, with a large slotted head that can be turned by a coin,occupying one end of the column 30. The screw is so arranged that, when it is tightened, it compresses axially an annular rubber block surrounding the axis of the screw; the block is thereby forced to expand radially outwards and to provide an adjustable frictional engagement between parts of the column 30 that rotate with the door 31 and parts that are fixed relative to the housing 25.

At the rear corner of the housing 25, between the first side and the third side 28, is a column 38 at the bottom of which is provided means (not shown) for mounting the device. The mounting means is preferably arranged to be clamped to the side edge of the bonnet of a motor car or the adjacent edge of a front wing, or to be fastened to an existing wing-mirror mounting on the wing, so as to avoid the need to drill holes in the wing. The mounting means preferably includes a ball-and socket joint similar to the joint 14 to 16 described above.

The device is installed on a vehicle by mounting it on the front wing by means of the mounting means.

The device is then aligned with the transparent panel facing in a desired direction and the ball-joint is locked. The driver of the vehicle then adjusts the second mirror 32, by adjusting the position of the door 31 and the tilt of the second mirror about the rod 34, so that when in his usual driving position he sees in the second mirror an image of the first mirror 29 and of the view through the transparent panel 27.

In use, with the first side of the housing 25 extending substantially fore-and-aft and the front corner forwards as the vehicle moves, very little air enters the housing and as a result very little dust, spray, rain, and the like is deposited on the first mirror 29. The second mirror 32 is also protected, being in a region of dead air inside the door 31, and the transparent panel 27 is to some extent swept clean by the flow of air across it resulting from its oblique angle to the direction of motion.

As an example of suitable dimensions for a device as shown in Fig. 3 intended to be mounted on the lefthand side of a right-hand drive saloon car to afford a view forwards, the first mirror 29 may be 145 mm wide and 85 mm high, with an axis normal to the centre of -its reflecting surface parallel to the planes of the top and bottom walls 26 and at an angle of 200 to the plane of the first side of the housing 25, and its reflecting surface may have the same curvatures as the first mirror 9 of the first form of device. The second mirror 32 may be flat, and may be 160 mm wide and 90 mm high. The axis of pivoting of the door 31 may be 195 mm in front of the plane of the first mirror 29, and 20 mm to the right of the above-mentioned axis of that mirror; the axis of pivoting may be 10 mm behind the plane of the second mirror 32, and 100 mm from the corresponding axis of that mirror. The centres of the two mirrors may be substantially in the same horizontal plane.

The device shown in Fig. 3 is not symmetrical, and the device may be a mirror image of that shown, for use on the right-hand side of a car. Instead, or in addition, the device may be so constructed that the mounting means can be attached at the top of the column 38 and the device mounted upside-down with respect to the position described above and mounted on the other side of the vehicle.

Claims

What we claim is:

1. A viewing device for use on a vehicle comprising a housing, a first mirror mounted in the housing and a second mirror, the first mirror being so arranged in use to reflect light from a region in front of the device onto the second mirror and the second mirror being so arranged to reflect that light towards a user of the vehicle that the user can see an image of the said region in the second mirror, and a transparent plate so located as substantially to prevent air from flowing through the housing and impinging on the first mirror.

2. A device as claimed in claim 1, wherein the light path from the second mirror to the user is at a high angle to the common plane of the light paths to and from the first mirror.

3. A device as claimed in claim 1 or claim 2, wherein the transparent plate is in front of the first mirror.

4. A device as claimed in claim 3, wherein the transparent plate is at an angle of less than 600 to the light path through it to the first mirror.

5. A device as claimed in claim 4, wherein the transparent plate is at an angle of less than 450 to the light path through it to the first mirror.

6. A device as claimed in any one of claims 3 to 5, wherein the. housing extends forward of the transparent plate.

7. A device as claimed in any one of claims 1, 2, and 6 wherein, when the device is moving rapidly forwards, there forms within the housing between the front of the housing and the transparent plate a volume of air that is substantially at rest relative to the device.

8. A device as claimed in any one of claims 1 to 7, wherein the second mirror is mounted in the housing.

9. A device as claimed in any one of claims 1 to 7, wherein the second mirror, at least in an operating configuration of the device, extends away from the housing.

10. A device as claimed in claim 9, wherein the second mirror is so movably mounted that it can be brought into an inoperative position against or inside the hbusing.

11. A viewing deviceofor use on a vehicle comprising a first mirror arranged in use to reflect light from a region in front of the device onto a second mirror that is arranged in use to reflect that light to a user of the vehicle, wherein the normal at the centre of the first mirror is at approximately 270 to a notional axis such that a light ray travelling along it meets the centre of the first mirror and is reflected to the centre of the second mirror, and wherein the normal at the centre of the second mirror is at an angle of approximately 370 to a first plane containing the said axis and the centre of the second mirror, and at an angle of approximately 360 to a second plane containing the said axis and perpendicular to the first plane.

12. A device as claimed in claim 11, wherein the second mirror is adjustably mounted so that its orientation may be varied according to the position of the user.

13. A device as claimed in claim 11 or claim 12, wherein the first mirror is convex.

14. A device as claimed in claim 13, wherein the reflective surface of the first mirror has a radius of curvature of 2000 mm in the first plane and of 1500 mm perpendicular to that plane.

15. A device as claimed in any one of claims 11 to 14, wherein the second mirror is a plane mirror.

16. A device as claimed both in any one of claims 1 to 10 and in any one of claims 11 to 15.

17. A mounting for attaching a device to the exterior of a vehicle in a position visible to a user of the vehicle, comprising a clamp arranged to engage an edge portion of a door of a vehicle that surrounds a window in the dpor, an arm attached to the clamp and arranged to lie generally parallel to the window extending from the clamp towards a central portion of the window, and means for attaching a device to the arm at a point remote from the clamp.

18. A mounting as claimed claim 17, wherein the clamp comprises a first jaw fixed to an end portion of the arm, a second jaw mounted on the arm for sliding movement along the arm, and means for controlling the separation between the jaws.

19. A mounting as claimed in claim 18, wherein the means for controlling the separation between the jaws comprises screw-threaded means.

20. A mounting as claimed in any one of claims 17 to 19, wherein the length of the arm between the clamp and the attaching means is adjustable.

21. A device provided with a mounting as claimed in any one of claims 17 to 20.

22. A device as claimed in claim 21, wherein the attaching means comprises a ball on one of the device and the arm, an externally screw-threaded projection on the other of the device and the arm, and an internally screw-threaded collar captive on the ball and arranged to screw onto the projection.

23. A device as claimed both in any one of claims 1 to 16 and in claim 21 or claim 22.

24. A viewing device for use on a vehicle, substantially as hereinbefore described with reference to, and as shown in, Figs. 1 and 2, or Fig. 3, of the accompanying drawings.

25. A vehicle fitted with a viewing device as claimed in any one of claims 1 to 16 or 21 to 24.