FR2815909A1 - SUSPENSION LEG HAVING AN ADJUSTABLE SPRING CUP - Google Patents

Abstract

The invention relates to a suspension strut comprising an adjustable spring cup (9), constituted by an oscillation damper and by a vehicle spring which is produced in the form of a helical compression spring (3) and clamped between two spring cups. The adjustable spring cup (9) acts as a support piece (11) which is connected to a housing (5) of the vibration damper. The invention is characterized in that the support piece (11) is arranged on the housing (5) at the outlet of the piston rod (7). In addition, the adjustable spring cup (9) is pressed pivotally against the support piece (11) by the helical compression spring (3), while to maintain the adjusted position of the spring cup (9 ) a fixing device (13) is provided.

Description

The invention relates to a suspension leg comprising a cup of

  adjustable spring, constituted by an oscillation damper and by a vehicle spring which is produced in the form of a helical compression spring and clamped between two spring cups, the adjustable spring cup acting as a support piece which is connected

  to a housing of the vibration damper.

  Such suspension struts which include a helical compression spring acting as a vehicle spring and having an oscillation damper are often exposed to practically uncontrollable transverse forces which cause disadvantageous friction between the piston rod and the housing. In this case, these are transverse forces which are exerted by the helical compression spring on the vibration damper via the spring cup connected to the housing. These helical compression springs cannot be made as regularly as they exert the weakest transverse force possible on the suspension strut, once the spring cup is fixed, that is to say that the irregularities which arise during of the manufacture of helical compression springs lead to the geometrical center line differing from the line of action of the elastic force in helical compression springs. This also applies to helical compression springs whose final turns are contiguous and tapered. Consequently, in mass production of suspension struts, the friction of the individual suspension struts differs from each other due to the different transverse forces exerted by the spring.

  compression compression on the housing of the vibration damper.

  To reduce the transverse force exerted by the helical compression spring on the suspension leg, it is known to arrange the spring cup connected to the housing in an inclined and / or eccentric manner with respect to the axis of the damper, this why we classify helical compression springs into various groups by an expensive sorting, and

  a special spring cup is then associated with each group.

  DE 26 56 707 Ai and US-PS 4 366 969 are known for adjusting a desired level height of a motor vehicle.

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  to arrange, in the case of suspension legs, the spring cup in an adjustable manner by an axial translation on the housing. In addition, document DE 198 49 991 A1 shows a suspension strut whose support of the helical compression spring is adjustable, a spring cup that can be pivoted or else the two spring cups being arranged with pivoting ability. Due to the pivoting of the spring cup in action connection with the housing due to the elastic force of the helical compression spring, the middle of the spring cup shifts and the distance of the line of action of the spring from the axis of the housing changes, which is why a transverse force is again exerted by the helical compression spring on the housing and thus a bending torque is exerted on the oscillation damper, so that it always exists an influence

  uncontrollable friction between the piston rod and the housing.

  The objective underlying the present invention is to provide a suspension leg with an adjustable support of a helical compression spring, in which the transverse force exerted by the helical compression spring on the shock absorber is allowed. oscillations by adjusting the spring cup, and

this at low costs.

  This object is achieved by the present invention. Advantageous developments and embodiments of the cup suspension strut

  adjustable spring are the subject of the following description.

  The required minimization of the transverse force exerted by the helical compression spring on the oscillation damper is possible when the bearing part cooperating with the spring cup is arranged on the housing at the outlet of the piston rod. and that the adjustable spring cup is pressed against the support piece by the tight helical compression spring, while to maintain the adjusted position of the spring cup, a fixing device is provided. Thanks to this, it is possible to adjust the transverse force, exerted by the helical compression spring mounted on the shock absorber.

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  oscillations, at the lowest possible value in a jamb of

  suspension on the test bench, and fix this setting.

  A simplification is obtained for the adjustment of the spring cup when the support piece comprises a surface in the form of a spherical cap on which the adjustable spring cup is arranged, by a support surface of corresponding shape. Thus, both a very good support of the suspension leg on the housing of the oscillation damper and a possibility of very fine adjustment of the suspension are achieved.

spring cup.

  Advantageously, the spring cup comprises an approximately tubular body which is provided at its lower end with a support for the helical compression spring, while at the upper end is provided a cap-shaped bearing surface spherical for the support piece. The support for the helical compression spring can therefore be inclined and / or moved eccentrically relative to the axis of the oscillation damper. The favorable position found for the spring cup is maintained by the fixing device, and this fixing device is formed for example by at least three locking screws arranged in regular distribution on the periphery of the housing in the tubular body. To maintain the adjustment found for the spring cup without obstacle on the part of the helical compression spring, or to be able to also carry out a fine adjustment, the locking screws are arranged in an extension, provided below the support, of the body.

approximately tubular.

  Other embodiments for the fixing device are produced by forming several moldings distributed over the periphery and bearing on the external surface of the housing. These moldings are arranged for example at the extension of the tubular body, or else the moldings, abutment surfaces or other bearing parts acting on the external surface of the housing are arranged on a fixing ring connected to the tubular body. We can also preform this ring

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  fixing separately from the suspension leg and then connect it

  firmly to the extension of the tubular body.

  Other adjustment possibilities are made when the support piece is in action connection with an adjustment ring fixed in rotation with the housing. Thus, for example in the case of axially high and strongly inclined spring cups, a better correction of the line of action of the helical compression spring can be carried out. This is also advantageous when an adjustment by tilting of the spring cup means that the structural space available for the suspension strut would no longer suffice. To this end, the adjustment ring has a cylindrical outer surface which is arranged so as to extend eccentrically with respect to the cylindrical housing, and / or the support piece is in action connection with the adjustment ring by a hole that extends eccentrically to the exterior surface. Once the adjustment has been made, a rotational connection is established which ensures that the adjustment found can no longer be modified. To turn the support piece with respect to the adjustment ring, an adjustment tool is provided which is supported for example on the adjustment ring and which acts on the support piece which is provided with a

toothed crown.

  In the following, the invention will be explained in more detail with reference to exemplary embodiments illustrated in the drawings. The figures show: Figure 1, a detail of a suspension leg at the level of the adjustable spring cup and in action connection with the housing; FIG. 2, an embodiment of the adjustable spring cup, the fixing device being arranged below the support for the helical compression spring; Figure 3, another possibility of eccentric adjustment for the spring cup; Figure 4, another embodiment for an eccentric adjustment of the spring cup; Figure 5, a fixing device which is formed by moldings of the extension of the tubular body; and

2815909

  Figure 6, a fixing device produced by deformation of the fixing ring. The detail of the suspension leg illustrated in FIG. 1 shows an oscillation damper 1 which comprises at the exit of a piston rod 7 a support piece 11 which rests on the housing 5 of the damper of oscillations 1 and which has a surface in the form of a spherical cap 15. A helical compression spring 3 acting as a vehicle spring is clamped between an upper spring cup not shown and an adjustable spring cup 9. The spring cup adjustable 9 is constituted by a body 10 extending axially and approximately of tubular shape which projects into the lower turns of the helical compression spring 3 and which carries on the one hand the support 21 adapted to the lower end of the compression spring helical 3 and which further comprises a recessed end provided with a bearing surface 17, the bearing surface 17 being adapted to the surface in the form of a spherical cap that 15 of the support piece 1 1. In addition, there is provided in the body 19 extending axially of the adjustable spring cup 9 a fixing device 13 which acts on the housing 5 and which is constituted by at least three locking screw 23

  arranged in regular distribution on the periphery.

  To minimize the friction which appears between the piston rod 7 and the housing 5 during the movement of movement inwards and outwards during the serial production of the suspension struts, the pivoting device is pivoted on the test bench. , the spring cup 9 on the support piece 11, so that the transverse force exerted by the helical compression spring 3 on the housing 5 reaches the smallest possible value. This found setting is held captive by the fixing device 13 formed by the locking screws 23, so that during operation there can be no change in the transverse force exerted by the helical compression spring. The locking screws 23 can also be used for fine adjustment of the spring cup 9 and they are in any case blocked against loosening once the adjustment has been made, which can be

  do by known measures in mechanical engineering.

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  The embodiment according to FIG. 2 differs from that according to FIG. 1 by a simple accessibility to the locking screws 23. These are arranged in an extension 25, provided below the support 21, of the tubular body 19 and can be adjusted and locked without obstacle on the part of the helical compression spring 3. FIG. 3 shows a possibility of additional adjustment for the spring cup by an adjustment ring 27 which is arranged eccentrically on the housing 5 and which has an external surface

  29 which cooperates with a corresponding bore in the support piece 11.

  The bore of the support piece 11 can also be provided in the form of an eccentric bore 31, whereby a greater adjustment possibility is achieved. A possibility of adjustment by which the line of action of the helical compression spring can be radially modified is particularly advantageous when during the adjustment of the spring cup on the support piece 11 the radial structural space available for the suspension strut is not enough because

  a too strong tilting of the spring cup.

  To rotate the support piece 11 on the adjustment ring 27, a rotation device 33 is provided which is constituted by an adjustment tool which is supported in a hole for receiving the adjustment ring 27 and which engages by rotation with a toothing in a ring gear of the support piece 11. Once the adjustment has been made, the adjustment tool 37 is removed and a connection 43 is formed which is integral in rotation between the

  adjusting ring 27 and the support piece 11.

  FIG. 4 shows an alternative embodiment of the possibility of adjustment between the adjustment ring 27 and the support piece 11. The eccentric bore 31 in the support piece 11 is formed obliquely with respect to the axis and the adjustment ring is provided with a flange on which the support piece 11 rests. Once the adjustment has been made, the connection 43 is made integral in rotation which is formed for example by

a threaded pin.

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  FIG. 5 shows a fixing device 13 which is formed by moldings 39 distributed regularly over the periphery. These moldings 39 are provided in the lower extension 25 of the tubular body 19 and they are applied to the press after having adjusted the spring cup.

9.

  Another fixing device is illustrated in FIG. 6, the extension 25 of the tubular body 19 carrying another fixing ring 41 which can also be preformed separately with respect to the spring cup 9, in correspondence with the setting. of the spring cup 9 on the support piece 11, and which is fixed only afterwards on the

  extension 25 arranged below the support 21.

  The use of the adjustable spring cup described above is applicable not only for the adjustment on the test bench, but this adjustable spring cup also makes it possible to fix an adjustment for helical compression springs with approximately equal effect, while other coil spring groups also require other adjustments to the spring cup. These different adjustments can be made by means of the adjustable spring cup according to the invention without structural modification, so that the suspension struts are mounted at low cost.

also for this use.

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Claims (14)

claims   1. Suspension strut comprising an adjustable spring cup (9), constituted by an oscillation damper and by a vehicle spring which is produced in the form of a helical compression spring (3) and clamped between two spring cups , the adjustable spring cup acting as a support piece (11) which is connected to a housing (5) of the oscillation damper, characterized in that the support piece (11) is arranged on the housing (5) at the outlet of the piston rod (7), and in that the adjustable spring cup (9) is pressed with the option of pivoting against the support piece (11) by the helical compression spring (3), while to maintain the adjusted position of the spring cup (9) there is provided a device fixing (13).   2. Suspension strut according to claim 1, characterized in that the support piece (11) comprises a surface in the form of a spherical cap (15) on which the adjustable spring cup is arranged.   (9) by a bearing surface (17) of corresponding shape.   3. Suspension strut according to claims 1 and 2, characterized in   that the spring cup (9) comprises a body (19) extending axially and approximately in tubular shape which has at its lower end the support (21) for the helical compression spring (3), while the end upper is radially in   withdrawal and forms the support surface in the form of a spherical cap (17).   4. Suspension strut according to one or more of claims 1   to 3, characterized in that the fixing device (13) is formed by at least three locking screws (23) arranged in regular distribution on the   periphery of the housing (5) in the tubular body (19).   5. Suspension strut according to claim 4, characterized in that the locking screws (23) are arranged in an extension (25),   provided below the support (21), the tubular body (19). 9 2815909   6. Suspension strut according to claims 1 to 3, characterized in   that the fixing device (13) is formed by several moldings (39) distributed over the periphery and resting on the external surface of the housing (5).   7. Suspension leg according to claim 6, characterized in that the moldings (39) are arranged at the level of the extension (25) of the tubular body (19).   8. Suspension strut according to claim 6, characterized in that the moldings (39) or abutment surfaces acting on the outer surface of the housing are arranged on a fixing ring (41) connected to the tubular body (19).   9. Suspension strut according to one or more of claims 1   8, characterized in that the support piece (11) is in action connection with an adjustment ring (27) fixed in rotation with the housing (5).   10. Suspension strut according to claim 9, characterized in that the adjustment ring (27) has a cylindrical outer surface (29) which is arranged so as to extend eccentrically relative to to the cylindrical housing (5).   11. Suspension strut according to claim 9, characterized in that the support piece (11) is in action connection with the adjustment ring (27) by a bore (31) which extends eccentrically by compared to the exterior surface.   12. Suspension strut according to claims 9, 10 and 11,   characterized in that a rotational integral connection (43) is provided   between the support piece (11) and the adjustment ring (27). 2815909   13. Suspension strut according to claims 9 to 12, characterized   in that a rotation device (33) is arranged between the support piece (11) and the adjustment ring (27).   14. Suspension strut according to claim 13, characterized in that the rotation device (33) is formed by a ring gear (35) which is arranged in the support piece (11) and in which engages a adjustment tool (37) which can be inserted into a hole for receiving the adjustment ring (27) and provided with teeth corresponding.