Cable actuated mirror tilt control

Abstract: Tilt control means for an exterior "break-away" mirror assembly (10) of a motor vehicle comprises at least two lines (18) extending from the mirror back (13) of the mirror assembly over rigid curved guide line surfaces (20, 21, 22, 25, 26, 27) which guide the lines between the mirror back (13) and the control lever (24, 64), the lines being secured at the control lever ends in a manner to provide maximum line movement in response to control lever movement within an available space at the inner end of the control lever.

Description: This invention relates to tilt control means for an exterior "break-away" mirror assembly of a motor vehicle, having a mounting frame of shape to be secured to an exterior portion of the motor vehicle body, a mirror casing, a mirror back carrying a mirror and coupled to the casing by a tilt joint for tilting about at least an horizontal axis, and hinge means so operatively coupling the mirror casing to the mounting frame as to provide means for the mirror casing "break-away" about at least one generally vertical axis; the tilt control means being of the type which comprises a control lever having a convex part-spherical protuberance intermediate its ends engaging in a concave part-spherical socket for universal pivotal movement, a plurality of retention anchors on the mirror back and a corresponding number of flexible lines each extending from a respective retention anchor to an end of said control lever, and rigid curved line guide surfaces which guide said lines between the mounting frame and the mirror back to extend through a zone adjacent said "break-away" axis. Tilt control means of this type is disclosed in DE-A-2 715 335. According to the invention, in tilt control means of the type described above, the retention anchors on the mirror back are spaced radially from said tilt joint, a corresponding number of additional rigid curved line guide surfaces are located radially outwardly from and uniformly spaced around said control lever, and each flexible line extends from a respective retention anchor, around a respective additional curved line guide surface to a said control lever end, the paths of said lines between said additional curved line guide surfaces and said control lever end being substantially in a common plane containing said control lever end. Two embodiments of the invention are described hereunder in some detail with reference to and as illustrated in the accompanying drawings, in which: Figure 1 is a diagrammatic representation of an arrangement wherein the lines extending from the mirror back to the control lever are secured to the inner end of the control lever, passing over rigid curved line guide surfaces; Figure 2 is a fragmentary illustrative section showing the arrangement of Figure 1 when applied to a spigot type "break-away" mirror; Figure 3a is fragmentary section which illustrates an arrangement similar to Figure 1 in principle but applied to a "break-away" mirror of the two "break-away" axes type illustrating how the invention is applied to extend unsheathed lines through the two zones adjacent each of the "break-away" axes; Figure 3b shows how the lines are deflected by rigid curved guideline surfaces upon forward "break-away"; Figure 3c illustrates how the lines are deflected by curved guideline surfaces upon rearward "break-away"; Figure 4a is a partly sectioned end view of Figure 3a showing the way in which lines attached to the inner end of the control lever extend around rigid curved guideline surfaces positioned around the lever inner end, the lines being attached to the lever inner end; and Figure 4b shows a further development wherein the lever inner end itself carries a rigid curved guideline surface and the lines extend around that surface and are anchored to a fixed structure (which can be the control lever retention means). In the first embodiment, illustrated in Figures 1 to 4b, there is provided tilt control means for an exterior "break-away" mirror assembly 10 of a motor vehicle which has a mounting frame 11 of shape to be secured to an exterior portion of the vehicle body, a mirror casing 12, a mirror back 13 within the casing 12, which carries a mirror 14, and the mirror back 13 being coupled to the casing 12 by means of a ball type tilt joint 15 for tilting the mirror and mirror back with respect to the casing about two axes. In Figure 2, there is illustrated an arrangement comprising an inner hollow spigot 16 which is upstanding from the mounting frame 11, and is surrounded by an outer hollow spigot 17 which forms portion of the casing 12, the outer spigot being rotatable about the inner spigot to provide the required axis A-A for "break-away" of the casing with respect to the mounting frame in either forward or rearward direction. This arrangement is described in detail in our patent application EP-A-0 460 893 (91304998.7) with a date of publication of 11.12.91. In this arrangement, three flexible unsheathed lines 18a, 18b and 18c (of long chain polyethylene) extend from retention anchors 19 on a mirror back spaced radially from the tilt joint 15, over rigid curved guideline surfaces 20, 21 and 22, to an operating locality where they are connected to the inner end 23 of a control lever 24, but pass over further rigid curved guideline surfaces 25, 26 and 27 which are spaced radially outwardly from the inner end 23 of lever 24. There needs to be a spring tensioner for the lines 18, and this is effected in the embodiment of Figure 2 by the guide 22 being on the end of a plunger 29 which is movable in the mounting frame 11, and is spring loaded outwardly by a small compression spring 30. As illustrated the guide surfaces are all stationary surfaces of circular section pins but obviously some or all can involve rotatable pulleys or sleeves. In the arrangement of Figures 3 and 4, the spring tensioner comprises a small pivoted arm 33 which is tensioned by means of a torsion spring 34 (Figure 3a), and carries on it a pin 35, the surface of which constitutes the curved line guide surface for the lines 18. The same arrangement of the guides 25, 26 and 27 is used as in Figure 2. There is also provided a guide plate 38 having an aperture, an edge of which guides the lines before they pass over the guides 25, 26 and 27. Between the mirror back 13 and the mirror case 12 there is located a reaction member 39 which contains guide ferrules 40 for guiding the lines 18 towards the anchors 19 on the mirror back 13. As illustrated in Figures 3b and 3c, "break-away" takes place around the two axes A1-A1 (Figure 3b) and A2-A2 (Figure 3c), and in order to reduce change of tension in the lines 18, the guides 41 and 42 are in respective "break-away" zones close to the axes A1-A1 and A2-A2. The guide 41 is carried on the mirror casing 12 and guide 42 is carried on the mounting frame 11. As best seen in Figure 3a, the lever arm is supported from the mounting frame 11 by means of a frame 45 which contains a part-spherical socket 46, the socket 46 accommodating a part-spherical protuberance 47 intermediate the ends of the control lever 24, but in most applications the frame 45 will be of shape to suit the available space within which the lever inner end 23 must move. Although the arrangement of Figures 3a, 3b, 3c and 4a is usually adequate for providing the required movement of the mirror back 13, in some instances advantage is achieved by having a further guide surface 48 (Figure 4b) on the inner end of the lever arm 24. The ends of lines 18 are anchored at the anchor points 50a, 50b and 50c which are fast with the control lever retention means, which as illustrated, are fixed to the mounting frame 11, although it may be at other localities. With the arrangement of Figure 4b, the movement of the inner end 23 of lever 24 is doubled by the "pulley effect" of the guide surface 48.

Claims: Tilt control means for an exterior "break-away" mirror assembly of a motor vehicle, having a mounting frame (11) of shape to be secured to an exterior portion of the motor vehicle body, a mirror casing (12), a mirror back (13) carrying a mirror (14) and coupled to the casing (12) by a tilt joint (15) for tilting about at least an horizontal axis, and hinge means (16, 17; 41, 42) so operatively coupling the mirror casing (12) to the mounting frame (11) as to provide means for the mirror casing "break-away" about at least one generally vertical axis; the tilt control means comprising a control lever (24) having a convex part-spherical protuberance (47) intermediate its ends engaging in a concave part-spherical socket (46) for universal pivotal movement, a plurality of retention anchors (19) on the mirror back (13) and a corresponding number of flexible lines (18) each extending from a respective retention anchor to an end (23) of said control lever, and rigid curved line guide surfaces which guide said lines (18) between the mounting frame (11) and the mirror back (13) to extend through a zone adjacent said "break-away" axis, characterised in that the retention anchors (19) on the mirror back (13) are spaced radially from said tilt joint (15), a corresponding number of additional rigid curved line guide surfaces (25, 26, 27) are located radially outwardly from and uniformly spaced around said control lever (24), and each flexible line extends from a respective retention anchor, around a respective additional curved line guide surface (25, 26, 27) to a said control lever end (23), the paths of said lines (18) between said additional curved line guide surfaces (25, 26, 27) and said control lever end (23) being substantially in a common plane containing said control lever end (23). Tilt control means according to claim 1, wherein each control line (18) is secured to said control lever end (23). Tilt control means according to claim 1, wherein a still further rigid curved line guide surface (48) is formed on said control lever end (23), and an unsheathed portion of each control line (18a, 18b, 18c) extends around said still further guide line surface (48) and is secured to further control lever retention means (50a, 50b, 50c). Tilt control means according to claim 1, 2 or 3, wherein said hinge means (16, 17; 41, 42) comprises inter-engaging co-axial hollow spigots (16, 17) on the mirror casing (12) and mounting frame (11), and said flexible lines (18) extend through the hollow spigots (16, 17). Tilt control means according to claim 1, 2, or 3, wherein there are two said hinge means, one near a forward edge of said casing (12) and the other near a rear edge of said casing (12), said rigid curved line guide surfaces including a surface (42) carried by the mounting frame (11) near one of said hinge means and a surface (41) carried by the casing (12) near another of said hinge means. Tilt control means according to any preceding claim, wherein said concave part-spherical socket (46) is formed in said mounting frame (11). Tilt control means according to any preceding claim, further comprising spring loaded tensioning means engaging at least one of said lines (18) between its ends to thereby retain some tension in all said lines (18). Tilt control means according to any preceding claim, wherein said flexible lines (18) are unsheathed.

Inventors: GILBERT ROBERT WILLIAM, GILBERT, ROBERT WILLIAM
Applicants: BRITAX RAINSFORDS PTY LTD, BRITAX RAINSFORDS PTY. LIMITED
Application year: 1992
Main classification: B60R1
IPC codes: B60R1