Title of Invention

CLAMPING MECHANISM WITH A SHAFT

Abstract

Clamping mechanism with a shaft (1), one end thereof being provided with a first abutment (2) and a second abutment (5) arranged at a distance being actively con- nected with an actuating member (6) allowing tilting movement around the axis of the shaft (1). On one of the surfaces (8, 24) facing each other of the second abutment (5) or the actuating member (6) roller tracks (19) for rollers (10) extending in the way of screw surfaces are provided which are freely rotatable lodged in the abutment (5) or the actuating member (6). The components to be tensioned or clamped, respectively, are arranged between the two abutments (2, 5). The tilting angle of the actuating member (6) is limited by at least two stops (14). The second abutment (5) and the" actuating member (6) are retained in at least one o{ the two positions limited by the stops (14), preferably in the clamping position, by at least one catch (15,22) acting in radial direction. (Fig. 1)

Full Text

The present invention relates to a clamping mechanism with a shaft, one end thereof being provided with a first abutment and with a second abutment being lodged at a distance thereof on the shaft, with an actuating member allowing tilting move¬ment around the axis of the shaft being actively connected therewith, there being pro¬vided roller tracks for the roller members, in particular cylindrical rollers, extending in the way of screw surfaces on one of the surfaces facing each other of the second abutment or the actuating member, being freely rotatable lodged in the abutment or the actuating member, and the components to be clamped or tensioned, respectively, being arranged between the two abutments and the actuating member being freely tiltable from a tensioning and clamping position into a released position and vice versa. A clamping device of this type is, for instance, known from EP 0 600 700 B1. The roller track provided therein has three zones, i.e. a first zone on which the roller rests in the undamped position, a second zone representing a culminating point within the roller track which has to be overtravelled by the roller upon actuation of the actuating lever, and a third zone serving as rest position in the clamped position. The seat-engaging surface of said rest position being lower as the culmination point, so that upon passing from the undamped position into the clamped position the highest possible tension force drops again upon reaching the culmination point, when the roller moves into its rest position, so that part of the tension force is being lost. EP 0 493 181 B1 likewise shows and discloses a clamping mechanism of this type. In this case, ball pairs are provided as rollers which are located in bores of the actuating member, tiltably arranged between two abutments. Here too, the rollers run on roller tracks formed in the way of screw surfaces when tilting the actuating mem¬ber. In the damped position, these rollers lie in indentations provided in the roller track so that in this case exactly that disadvantageous effect as described here¬inabove occurs. On the basis of the prior art, the present invention aims at avoiding the disad¬vantages of such known clamping devices so that, when the actuating member is tilted into Its clamping position, also the maximum or ciamping rorce is being reached. To-solve this problem, the invention provides that the second abutment and the actu¬ating member are being retained in at least one of the two positions, preferably in die damping position, by at least one catch acting in radial direction. Accordingly the invention provides a clamping mechanism with a shaft (1), one end thereof being provided with a first abutment (2) and with a second abutment (5) being lodged at a distance thereof on the shaft (1), with an actuating member (6) allowing tilting movement around the axis of the shaft (1) being actively connected therewith, there being provided roller tracks (19) for the rollers members (10), in particular cylindrical rollers, extending in the way of screw surfaces on one of the surfaces (8, 24) facing each other of the second abutment (5) or the actuating member (6), being freely rotatable lodged in the abutment (5) or the actuating member (6), and the components to be clamped or tensioned, respectively, being arranged between the two abutments (2, 5) and the actuating member (6) being freely tillable from a tensioning and clamping position into a released position and vice versa, characterized in that the second abutment (5) and the actuating member (6) are held in at least one of the two positions, preferably in the clamped position, by at least one catch (15, 22) acting in the radial direction with respect to the axis of the shaft (1). One embodiment of the present invention will now be described in more detail, by way of example, with reference to the accompanying drawings, in which: Rg. 1 is a front view of the clamping mechanism; Rg. 2 is a front view of the actuating member; Rg. 3 is a side view - viewed in the direction of arrow A in Rg. 2; Rg, 4 Is a side view - viewed In the direction of arrow B In Rg. 2; Rg. 5 is a front view of the second abutment, and Rg. 6 Is a side view of the second abutment, viewed in the direction of arrow C in Rg.5; Rg, 7 and 8 are front views of the actuating member in Rg. 1, but showing the position of the cam in the two conditions of the actuating member; Rg. 9 is a front view of the second abutment and the actuating member viewed in the direction of arrow D in Rg. 1; Rg. 10 is a detail. Rg. 11 is a detail of Rg. 7 as a variant of the embodiment. The damping mechanism illustrated in Rg. 1 comprises a shaft 1. An abutment 2 is attached to one end of the shaft 1, for instance by means of a nut 3 screwed onto the end thread of the shaft 1 and secured thereon. At a distance of said abutment 2, a second abutment 5 is provided through which the shaft 1 passes with a slight play, so that the shaft 1 is rotatable relative to the abutment 5. An actuating member 6 with an actuating lever 7 co-operates with the abutment 5, the actuating member 6 being connected to the shaft 1 and secured against rotation in the embodiment shown. Said actuating member 6 has, on the surface 8 facing the adjacent second abutment 5, two indentations 9 symmetrically arranged relative to the shaft 1, in which freely rotatable cylindrical roller members 10 are lodged, in this case formed as cylin¬drical rollers, the arrangement being designed in a way that the rollers 10 slightly pro- trude from the surface 3. The axes of the two rollers 10 are in alignment and intersect the axis of shaft 1. A toothed wheel 12 is stationary lodged on a laterally protruding section 11 of the actuating member 6, which is part of a hydraulic damping or braking device 13. The actuating member 6 is also provided on its side with two hump-like stops 14. In the peripheral area of the actuating member 6, and in the present case between the two stops 14, a leaf spring 15 is attached with one of its ends 16. Said leaf spring 15 has a wedge¬like deformation 17 extending parallel to the axis of the shaft 1 and orientated against the axis. The disk-like abutment 5 has a bore hole 18 through which passes the shaft 1 thereby having a play. Roller tracks 19 extending in the way of screw surfaces are formed on either side of the bore hole 18. An end toothing 20 is provided on a part of the periphery corresponding with respect to its extension to the tilting angle of the actuating member 6. Furthermore, in the present case claws 21 are provided on the second abutment 5 laterally projecting thereof. On the surface provided with the roller tracks 19 there is also provided a cam 22 projecting from the surface 24 whose outer defining surface 23 extending in circumferential direction is spirally formed and the curve length of the cam 22 is approximately 40* The dimensions of the cam 22 and of the leaf spring 15 and their respective position relative to each other, respectively, being so that the leaf spring 15 or part of It, respectively, protrudes into the enveloping sphere of the spirally extending defining surface 23 of the cam 22. Upon proper assembly of the clamping mechanism, the surface 8 of the actuating member 6 Is positioned opposite the surface 24 of the second abutment 5, the claws 21 thereby lying between the stops 14 of the actuating member 6. The rollers 10 rest on the roller tracks 19. Fig. 7 shows the relative position of the spring 15 and the cam 22 relative to each other when the clamping mechanism is in an undamped condition, i.e., when It is released. In this case, the spring 15 is somewhat distanced from the cam 22 when the catch is released. However, it is also possible to design this arrangement in such a way that even with the catch in the released condition the spring 15 applies against the cam 22, for instance by pre-stressing it, as schematically illustrated in Pig. 11. Through relative rotation of the spring 15 and the cam 22 the spring 15 is radially turned and thus being bent. The spring 15 can thereby apply against the cam 22 along its entire length or apply only against a small part of the length of the cam 22. Depending on the constructive design, the factors of force are thereby mutually influ¬enced upon tilting, In order to activate the clamping mechanism, the actuating member 6 is tilted relative to the stationary second abutment 5 by means of the actuating lever 7, the rollers 10 running upwards on the screw-surface-like roller tracks 19. This brings the cam 22 within the sphere of the spring 15 and the wedge-like deformation 17 of the spring 15 within the enveloping sphere of said cam 22, thereby slightly lifting the spring 15, turning it radially outwards until the defining surface 23 of the cam 22 has entirely passed over the wedge-like deformation 17 of the spring 15 (Fig. 8), the spring 15 thereupon radially snapping back inwards, thus preventing back-turning of one part relative to the other by acting as a catch. The claws 21 then having reached their one limit position. In Figs. 7 and 8, said claws and their respective positions are illustrated in dashed lines. As a result of the above described tilting of the parts rela¬tive to each other, the axial distance of the actuating member 6 and the abutment 5 is increased by the rollers running upwards on the screw-face-like roller tracks. Upon said tilting of the parts relative to each other, the toothed wheel 12 is actuated by the end toothing 20. Said toothed wheel 12 co-operates with a hydraulic jamping or braking device 13, so that the actuating member 6 is constantly tillable by neans of the actuating lever 7 against an evenly acting force. In order to release the clamping mechanism, the actuating member 6 is tilted )ack into its original position by means of the actuating lever 7, the spring 15 thereby >eing lifted by the inclined shoulder 25 of the cam 22, thus releasing the catch. In the embodiment shown the spring 15 lies, when viewed from the axis of the shaft 1, outside of the cam 22. It is within the scope of the present invention to ar¬range the spring at the inside, so that, when viewed from the axis of the shaft 1, it is positioned at a smaller distance than the cam 22. In this case, the cam is to be formed according to its described function. While the rollers in the described embodi¬ment of the invention are lodged in the actuating member 6, it is also possible to ar- range them in the abutment 5 and to provide the roller tracks for said rollers in the actuating member 6. Instead of a leaf spring 15 extending in peripheral direction and being attached with its end 16 to the actuating member 6 , it is also possible to pro¬vide a spring acting in radial direction which may be formed by an insertion member (ball) as catch member. The screw-surface-like roller tracks may be somewhat spirally turned so that the contact points between the rollers and the roller track lie on a spiral upon tilting of the actuating member 6 and the abutment 5 relative to each other, the axis thereof being formed by the shaft 1. In this case, said turning of the roller track is formed in such a way that the rollers are arranged in the tensioning or clamping position at the end of their rolling path as near to the shaft 1 as possible and move to a position far¬ther away from said axis upon releasing the clamping mechanism. The extent of this turning is very small and not shown in the drawing. The dashed line 27 in Fig. 1 indicates a U-shaped component which can, for instance, be part of an adjustable steering column of a motor vehicle, as illustrated and described in the documents mentioned hereinabove. It is also possible to provide spring assemblies between the two abutments 2 and 5 and the cheeks of the indi¬cated U-shaped component. The shaft 1 is preferably formed as an extensible screw. In the embodiment described, the actuating member 6 is attached torsion-proof to the shaft 1. It is also possible to section-wise flatten the cross-section of the shaft 1 and to apply a spring 26 to said flattened section (Fig. 10), supporting the tilting movement of the actuating lever 7 at least on part of the tilting way thereof. This is schematically illustrated in Fig. 10. Essential for the invention is the catch acting in radial direction, fixing the posi¬tion of the tiltable parts relative to each other in their clamping position. The force re¬quired for surmounting the catch is applied only by the actuating lever 7, The retaining force exerted by the catch has no influence on the tension force of the clamping mechanism. Legend as to the reference numbers 1 Shaft 14 Stop 2 Abutment 15 Leaf spring 3 Nut 16 End 4 Thread 17 Wedge-like deformation 5 Abutment 18 Borehole 6 Actuating member 19 Roller track 7 Actuating lever 20 End toothing 8 Surface 21 Claw 9 Indentation 22 Gtem 10 Roller 23 Defining surface 11 Section 24 Surface 12 Toothed wheel 25 Inclined shoulder 13 Hydraulic damping or 26 Spring braking device 27 Dashed line We claim: 1. Clamping mechanism with a shaft (1), one end thereof being provided with a first abutment (2) and with a second abutment (5) being lodged at a distance thereof on the shaft (1), with an actuating member (6) allowing tilting movement around the axis of the shaft fl) being actively connected therewith, there being provided roller tracks (19) for the rollers members (10), in particular cylindrical rollers, extending in the way of screw surfaces on one of the surfaces (8, 24) facing each other of the second abutment (5) or the actuating member (6), being freely rotatable lodged in the abutment (5) or the actuating member (6), and the components to be clamped or tensioned, respectively, being arranged between the two abutments (2, 5) and the actuating member (6) being freely tiltable from a tensioning and clamping position into a released position and vice versa, characterized in that the second abutment (5) and the actuating member (6) are held in at least one of the two positions, preferably in the clamped position, by at least one catch (15, 22) acting in the radial direction with respect to the axis of the shaft (1). 2. Clamping mechanism as claimed in claim 1, wherein on one of the surfaces (8, 2-4) facing each other of the second abutment (5) or the actuating member (6) a cam (22) protruding axially towards the other surface is provided, the defining surface (23) thereof extending in circumferential direction extending spirally, and the other surface (8) being provided with a spring (15) orientated towards the spirally extending defining surface (23), the spring (15) or part of it, respectively, thereby protruding into the enveloping sphere of the spirally extending defining surface (23) of the cam (22). 3. Clamping mechanism as claimed in daim 2, wherein the defining surface (23) of the earn (22) turned away from the axis of the shaft (1) extends spirally. 4. Clamping mechanism as claimed in daim 2, wherein the curve length of the cam (22) is approximately 40°. 5. Clamping mechanism as claimed in claim 2, wherein the spring (15) is formed as a leaf spring, said leaf spring being provided with a wedge-like deformation (17) extending parallel to the axis of the shaft (1) and orientated against the cam (22). 6. Clamping mechanism as claimed in one of claims 1 to 5, wherein the periphery of the second abutment (5) or the actuating member (6), respectively, in fact at least over the curve length corresponding to the shifting way of the actuating member (6), is provided with an end toothing (20) engaging into a toothed wheel (12) stationary arranged on the actuating member (6) or the second abutment (5), respectively. 7.Clamping mechanism as claimed in claim 6, wherein the toothed wheel (12) is part of a hydraulic damping and braking device (13). 8. Clamping mechanism as claimed in claim 1 or 6, wherein the shifting way of the actuating member (6) is limited by stops (14). 9. Clamping mechanism as claimed in daim 8, wherein the stops (14) or parts thereof, respectively, limiting the tilting angle of the actuating member (6) are formed by claws (21), axially protruding towards the latter, provided on the second abutment (5). 10. Clamping mechanism as claimed in one of claims 1 to 9, wherein the shaft (1) connecting the abutments (2, 5) is provided, at least on part of the length thereof, with a cross-section with a flattened section on the circumference thereof, against which a preferably pre-stressed spring (26) applies (Fig. 10). 11. Clamping mechanism as claimed in claim 2, wherein the spring (15) applies against the cam (22) or the defining surface (23) thereof in each position of the actuating member (6). 12. Clamping mechanism as claimed in daim 1 or 2, wherein Hie spring (15) is also pre-stressed when the catch is being released. 13. Clamping mechanism as claimed in claim 2 or 3, wherein the defining surface (23) of the cam (22) is provided with a dent-like indentation or an inclined shoulder (25) in or against which the spring (15) applies in the rest position. 14. Clamping mechanism with a shaft substantially as herein described with reference to the accompanying drawings.

Documents:

678-mas-98 abstract-duplicate.pdf

678-mas-98 abstract.jpg

678-mas-98 abstract.pdf

678-mas-98 claims-duplicate.pdf

678-mas-98 claims.pdf

678-mas-98 correspondence-others.pdf

678-mas-98 correspondence-po.pdf

678-mas-98 description (complete)-duplicate.pdf

678-mas-98 description (complete).pdf

678-mas-98 drawings.pdf

678-mas-98 form-19.pdf

678-mas-98 form-2.pdf

678-mas-98 form-26.pdf

678-mas-98 form-4.pdf

678-mas-98 form-6.pdf

678-mas-98 others.pdf

678-mas-98 petition.pdf