GB2054496A

GB2054496A - Remotely controlled rear-view mirrors

Info

Publication number: GB2054496A
Application number: GB8025080A
Authority: GB
Original assignee: Kienzle Uhrenfabriken GmbH
Current assignee: Kienzle Uhrenfabriken GmbH
Priority date: 1979-08-04
Filing date: 1980-07-31
Publication date: 1981-02-18
Also published as: GB2054496B; DE2931787A1; FR2462303A1; DE2931787C2

Abstract

An adjusting mechanism for a motor vehicle external rear view mirror comprising two electric motors 20 one of which can adjust the mirror support 13 about a first axis and the other of which can adjust the mirror support about a second axis, said mirror support being pivotally mounted on two connecting members 15, 18 in a mirror casing, and a reduction gear 24 and friction clutch 30, 31 being provided between each motor and an associated connecting member, said clutch permitting manual adjustment of the mirror support, each motor and its associated reduction gear being located in a casing, the last gearwheel 25 in the reduction gear being shaped to form a closure for the opening in the casing through which the drive to the connecting member passes from the motor, and a rotary actuating arm 17 frictionally mounted on said last gear wheel to convey the drive to said connecting member. <IMAGE>

Description

SPECIFICATION Adjusting mechanism for motor vehicle external rear view mirror The invention relates to an adjusting mechanism for a motor vehicle external rear view mirror.

German Patent Specification DOS 2644578 discloses an adjusting mechanism for such a mirror provided with two electric motors one of which can adjust the mirror for example about a vertical axis and the other of which can provide adjustment for example in a horizontal axis and the other of which can provide adjustment for example in a horizontal axis. A mirror support is mounted in pivoted manner on two connecting members in a mirror casing and a reduction gear and a friction clutch are provided between each motor and the associated connecting member, the friction clutch permitting manual adjustments of the mirror support. The two parallel electric motors each drive a plurality of successively connected spur gear elements each consisting of a large spur gear and a pinion connected thereto.The clutch is formed by a tapered portion on an output shaft on to which a tapered bore of a crank arm presses resiliently. A connecting rod is pivoted to the particular crank arm and is connected via a ball and socket joint to the mirror support.

This known adjusting mechanism has a number of disadvantages. The reduction gear used must have a reduction ratio of approximately 1:5000. Spur gears with such a large reduction ratio have the disadvantage that they have a considerable tolerance. In order that this tolerance on the mirror does not lead to vibrations, the gear output shafts are provided with a friction disc which presses resiliently against a friction surface fixed to the casing. Generally, however, such a measure is inadequate. As the friction force and consequently the holding power between the friction surface and the friction disc is dependent on weather and pollution conditions the frictional force must be made disproportionately large, so that powerful and therefore expensive drive motors must be used.

In addition, the spur gears used take up rather a large amount of space, so that a correspondingly large mirro casing must be provided to be able to house the adjusting mechanism.

An object of the present invention is to provide an adjusting mechanism of this type in which the aforementioned disadvantages are overcome.

According to the present invention an adjusting mechanism for a motor vehicle rear view mirror comprises two electric motors one of which can adjust the mirror support about a first axis and the other of which can adjust the mirror support about a second axis, said mirror support being pivotally mounted on two connecting members in a mirror casing, and a reduction gear and friction clutch being provided between each motor and an associated connecting member, said clutch permitting manual adjustment of the mirror support, each motor and its associated reduction gear being located in a casing, the last gear wheel in the reduction gear being shaped to form a closure for the opening in the casing through which the drive to the connecting member passes from the motor, and a rotary actuating arm frictionally mounted on said last gear wheel to convey the drive to said connecting member.

The invention also includes a motor vehicle external rearview mirror incorporating an adjusting mechanism as set forth above.

The invention can be performed in various ways but one embodiment will now be described by way of example and with reference to the accompanying drawings in which: Figure lisa cross sectional plan view through the mirror casing of a mirror according to the present invention; Figure 2 is a side view rotated through 90" in relation to Figure 1 of the adjusting mechanism, part of which is shown in section; Figure 3 is an enlarged view of part of Figure 2 rotated through 90" in relation thereto; Figure 4 is a detail view of part of Figure 3 shown partly in section and partly in cross-section; Figure 5 is a plan view of Figure 4; Figure 6 is a detailed view of another part of Figure 3; and, Figure 7 shows three view of the mirror support ball joints.

As shown in Figure 1 adjusting mechanism 12 is located in a mirror casing 11 and carries a diagrammatically represented mirror support 13. Mirror support 13 is carried centrally at 14 by a ball and socket joint (not shown) in Figure 1 and indicated diagrammatically in Figure 2. A further ball and socket joint 15 connects the mirror support 13 to a first connecting rod 16 which can be reciprocated by an actuating arm 17, so that the mirror support performs a swivelling movement about a first vertical axis at point 14. A further connecting rod 19 is pivoted to the mirror support by means of a ball and socket joint 18 and its reciprocation leads to a swivelling of mirror support 13 in a second horizontal axis about the point 14.

The swivelling movements are caused by two electric motors located in a common casing 19, one of the electric motors 20 is shown in the sectioned part of Figure 2. Casing 19 is formed from two cup-shaped casing parts 21 and 22, in which the electric motors 20 with the associated gearing are located. The two casing parts 21 and 22 are identical to one another, but displaced by 1800.

At one end each of the casing parts 21 and 22 is closed by a cover 23 which acts as a mounting support for the motor 20. A pinion located on the motor shaft drives a reduction gear train 24, whose final gear wheel 25 is constructed as a closure for the open end of the casing. A rotary actuating arm 17, or 17' is mounted on this last gearwheel 25 with a friction contact. This gear wheel 25 thus closes the opening in the casing through which the drive from the motor 20 passes out of the casing.

The details of gear train 24 are most clearly shown in Figure 3. Two plates 1, 1' are used for the mounting of the gear. A pinion 2 located on the motor shaft drives a first gear wheel, whose pinion meshes with a second gear wheel 26. The pinion of the second gear wheel 26 engages with a third gear wheel 27, whose pinion engages with a fourth gear wheel 28, whose pinion drives a fifth gear wheel 29.

Pinion 3 of the fifth gear wheel engages with internal teeth on the final gearwheel 25. In orderto obtain a compact construction gearwheel 26 is mounted on the shaft of gear wheel 28 and gear wheel 27 is mounted on the shaft of gear wheel 29. The first gear wheel and gear wheels 28 and 29 are mounted between plates 1, 1'.

The final gear wheel 25 is constructed in cupshaped mannerwith an peripheral flange 30. Flange 30 engages behind the edge 31 of casing part 21 or 22. A gasket 4 is provided between flange 30 and edge 31 of casing part 21 or 22. A gasket 4 is provided between flange 30 and edge 31 and is secured to edge 31. To ensure the action of gasket 4 between flange 30 and plate 1' a corrugated leaf spring 5 is provided which presses the cup-shaped gear wheel 25 against the edge 31, so that there is friction contact between the casing edge 31 or gasket 4 and flange 30. This friction contact prevents the clearance in gear train 24 being transferred to the actuating lever 17, or 17'.

As is best seen in Figure 2 gear train 24 in casing part 22 or 21 is supported by means of lugs 32, which are positioned in the rear plate 1 and engage in recesses (not shown) in each casing part 21,22.

As is most clearly shown in Figure 6 each actuating arm 17,17' has a slotted ring 6 which overlaps the final gear wheel 25. This slotted ring 6 is pressed against the final gear wheel 25 by a slotted annular spring 7, so that the rotary actuating arm 17 and 17' is frictionally mounted on the gear wheel 25.

For axial securing purposes the final gear wheel 25 is provided with a peripheral V-shaped notch 33 in which a peripheral V-shaped projection of ring 6 engages.

To ensure a stable mounting of mirror support 13 actuating arm 17 is provided with a long bore 34 in which a long bearing bolt 35 which is at right angles to connecting rod 16 is located. This bearing bolt 35 has a fixing hole into which is pressed a clamping bolt 10, and the same construction is used for actuating arm 17' and connecting rod 19.

The rotation range of each actuating arm 17, 17' is limited by abutments fixed to the casing, for exam ple abutment 36 against which the abutments 37, 37' of actuating arm 17 engage, as shown in Figure 1.

The ball and socket joints 15, 18, and ball and socket joint at point 14 comprise resilient tabs 38 on the mirror support and ball inner inner surfaces 39 between the tabs. When making these spherical surfaces two axially positioned punches are used.

The resilient tabs 38 are shaped by a punch which is removed in the direction of the mirror support surface. The four contact surfaces 39 in the bottom of the spherical surface are formed by a second punch which is removed in the other direction. This ensures that the spherical surfaces have close tolerances.

The gear train 24 used has a good gear efficiency, so that small motors 20 can be used and which are correspondingly inexpensive. Only limited noise is produced by motor 20 and gear train 24. The front gear wheel 25 in conjunction with gasket 4 seals off the casing parts 21,22 in a liquid-tight manner, and function is also ensured at high temperatures, because the motors 20 only produce limited heat.

The adjusting mechanism 12 is constructed in a compact manner and takes up little space, so that the mirror casing 11 can have a flat construction. A uniform jerk-free, high friction moment is obtained due to ring 6 and spring 7. Due to the resilient arms 38 it is possible to easily remove the mirror support, which is for example necessary to replace a broken mirro glass. High vibration strength is ensured due to the stable three-point attachment of the mirror support to the ball joints 15,18 and piston 14.

Claims

1. An adjusting mechanism for a motor vehicle external rear view mirror comprising two electric motors one of which can adjust the mirror support about a first axis and the other of which can adjust the mirror support about a second axis, said mirror support being pivotally mounted on two connecting members in a mirror casing, and a reduction gear and friction clutch being provided between each motor and an associated connecting member, said clutch permitting manual adjustmentofthe mirror support, each motor and its associated reduction gear being located in a casing, the last gear wheel in the reduction gear being shaped to form a closure for the opening in the casing through which the drive to the connecting member passes from the motor, and a rotary actuating arm frictionally mounted on said last gear wheel to convey the drive to said connecting member.

2. A mechanism as claimed in claim 1 in which each motor casing is cup-shaped and forms part of a common casing, the open end of each cup being closed by the respective last gear wheel of each reduction gear.

3. A mechanism as claimed in claim 2 in which the open ends of the two cup-shaped casing parts are arranged on opposite sides of the common casing.

4. A mechanism as claimed in any one of claims 1,2 or 3 in which the two reduction gears employ spur gears.

5. A mechanism as claimed in any one of the preceding claims in which the last gear wheel is cup-shaped with a peripheral flange, which engages behind the edge of the opening in the casing and has an internal gear which is engaged by a pinion of a preceding gear wheel in the reduction gear.

6. A mechanism as claimed in claim 5 including means for resiliently engaging said flange on the last gear wheel towards the edge of the said opening.

7. A mechanism as claimed in claim 6 in which a gasket is provided between the flange and the edge of the opening and the resilient means comprise a corrugated leaf spring located between a mounting plate for the further gear wheels of the reduction gear and the back of the flange.

8. A mechanism as claimed in claim 6 or claim 7 in which the gasket is secured to the edge of the opening.

9. A mechanism as claimed in any one of claims 1-8 in which mountingsforthe reduction gear is provided with lugs which engage in recesses in the respective casings.

10. A mechanism as claimed in any one ofthe preceding claims in which the rotary actuating arm has a slotted ring which engages the last gear wheel.

11. A mechanism as claimed in claim 10 in which said slotted ring is surrounded by a slotted annular spring to resiliently press it against the final gear wheel.

12. A mechanism as claimed in claims 10 or 11 in which the last gear wheel has a peripheral V-shaped notch in which a peripheral V-shaped projection of the slotted ring engages.

13. A mechanism as claimed in any one of the preceding claims in which at least one of the connecting members has a bearing bolt which is at right angles thereto and which engages in a bore of the actuating arm and has a fixing hole in which engages a clamping bolt of the actuating arm.

14. A mechanism as claimed in any one of preceeding claims 1-13 in which five further gear wheels with pinions are provided, the second and fourth gear wheels and the third and fifth gear wheels being coaxial to one another.

15. A mechanism as claimed in claim 14 in which the second gear wheel is mounted on the shaft of the fourth gear wheel and the third gear wheel on the shaft of the fifth gear wheel and these shafts and the shaft of the first gear wheel are carried between two plates which act as mountings therefor.

16. A mechanism as claimed in any one of preceeding claims 1-15 in which the mirror support is fixed centrally to the mirror casing and to the connecting members by means of in each case one and ball and socket joint comprising a spherical surface formed by resilient tabs and ball inner surfaces located between the tabs.

17. A mechanism as claimed in any one of preceding claims 1-16 in which the rotary ranges of the actuating arms are limited by abutments fixed to the casing.

18. An adjusting mechanism for a motorvehicle external rear view mirror substantially as described herein with reference to and as shown in the accompanying drawings.

19. A motor vehicle adjustable external rear view mirror incorporating an adjusting mechanism as set forth in any one of preceding claims 1 - 18.

20. A motor vehicle adjustable external rear view mirror substantially as described herein with reference to and as shown in the accompanying drawings.