EP1593461A1 - Spring tensioner for tensioning a helical compression spring - Google Patents

Abstract

One of the clamping disks (8) is inserted between two windings of the spring (2) close to one end of the spindle (14), which is guided through an opening (22) in the disk (8) and fitted with the pressure element (5) and the clamping nut (6). The second disc (7) is attached to the spindle (14) and the spindle (14) axially moved until its hemispherical end (35) engages with a matching recess (47) in the center of the disk (7). The spring (2) can be tightened by rotating the tensioning nut (6).

Description

The invention relates to an inner tensioner for tensioning a helical compression spring according to the features in the preamble of claim 1.

From the prior art are especially for the automotive sector Internal tensioners for helical compression springs known with which these helical compression springs dismantled from appropriate shots of the chassis and can also be used again.

DE 37 20 018 discloses a generic inner clamp for Helical compression springs, which from a centric within a too exciting helical compression spring positionable and by means of a Clamping drive in its effective length changeable clamping element as well of two axially supported against the clamping element clamping plates to rest on each one spring coil of the helical compression spring. Both clamping plates have a central bore, wherein the drive-side 2. Spannteller in the assembled state at a shoulder of the clamping element supported. The clamping element comprises a threaded spindle in one Threaded tube, wherein at one end of the clamping element a drive and on opposite end radially outwardly projecting fingers are provided. The to be mounted on the clamping element at the occupied with radial fingers end 1. Spannteller points outgoing from the central bore, radially to outwardly facing recesses, with the central bore a form a common, approximately star-shaped opening, so that with radial fingers occupied end of the clamping element through the opening formed thereby can be passed. Angled offset to the outwardly projecting Recesses of the 1st clamping plate are in the surface of the 1st clamping plate Wells introduced in which the radial fingers in the assembled state of Internal clamps are held positively.

In practical use shows that the assembly of this spring tensioning device is complicated and in particular the threading of the with the radial fingers provided end of the clamping element with respect to a series assembly hard to handle.

Although the radial fingers and the depressions allow a certain Relativverschwenkung the threaded pipe to the 1st clamping plate. By the in the Principle three-point support of the radial fingers in the wells of the 1st Spanntellers can however come to a standstill when panning. As a result, a safe tightening a helical compression spring is not fundamental guaranteed.

The invention is - starting from the prior art - the task underlying, an inner tensioner for tensioning a helical compression spring create, even with Relativverschwenkungen between the tensioning drive and the loaded by the helical compression spring 1. Spannteller a ensuring perfect clamping of the helical compression spring.

This object is achieved with the in the characterizing part of claim 1 solved characteristics.

The fact that now on a thickened first end of the tensioning drive spherical segment-shaped surfaces and at a transverse slotted 1. Spannteller adapted to these surfaces spherical segment-shaped Inner surfaces are provided in a dome, is an almost full-surface Attachment of thickened 1st end achieved in the calotte, in all Pivoting positions of the clamping drive relative to the 1st clamping plate. The 1st end effectively forms a pendulum head of the tensioning drive.

The invention is both noticeable in an internal tensioner noticeable, in which the tensioning drive from a central threaded spindle, a along the threaded spindle displaceable threaded sleeve and a one Length of the threaded spindle and the threaded sleeve cross Protective sleeve is made, with the protective sleeve with the 2nd clamping plate and the free end of the threaded sleeve can be coupled to the 1st clamping plate, as well in an internal tensioner with a threaded spindle, a pressure piece and a Clamping nut, wherein the thickened 1st end of the threaded spindle with the 1. Clamping plate and the pressure piece with the 2nd clamping plate can be coupled.

A particularly advantageous embodiment of the inventive concept consists according to the features of claim 2 is that the first end of the tensioning drive to the second end formed hemispherical and a flat face on the circumference of straight edges and circular section-shaped Transition edge is limited. From the straight edges on the one hand and the circular section-shaped transition edges on the other hand spherical segment-shaped surfaces extend in the direction of the longitudinal axis of the tension drive. These surfaces are according to the invention designed that the radius of the surfaces between the straight edges and the longitudinal axis is greater than the radius of the surfaces between the Transition edges and the longitudinal axis is dimensioned. On the other hand corresponds to the Radius of the inner surfaces of the dome equal to the radius of the surfaces between the straight edges and the longitudinal axis.

It is also advantageous according to claim 3, that in the circumferential direction of the 1. Final measured length of the larger radius surfaces approximately Six times the length of the smaller radius surfaces.

A twist-proof embedding of the 1st end in the calotte of the 1st clamping plate is achieved according to the features of claim 4 characterized in that the Inner surfaces of the dome with straight edges and circular section-shaped Transition edges in the dome adjacent to the outside of the 1st clamping plate lead.

According to the features of claim 5 are on a shaft-like longitudinal section of the tension drive adjacent the 1st end two by one Peripheral bead provided separate constrictions. The Diameter of these constrictions is smaller than the width of the transverse slot in the 1st clamping plate. The diameter of the circumferential bead is larger measured as the width of the transverse slot, but smaller than the diameter the circular portion-shaped inner end of the transverse slot. In this way can the 1st Spannteller easily between two spring coils of Helical compression spring are introduced transversely. Then then the Spannantrieb be displaced in the longitudinal direction of the helical compression spring until that the 1st end engages in the calotte of the 1st clamping plate. After that can with Help the tension drive the helical compression spring between the 1st and the 2nd Clamping plate to be clamped.

To allow a fitter, at both ends of the tension drive To be able to apply tools for twisting or countering, see the features of claim 6, that at the 1st end and / or the 2nd end of the Spannantriebs axial projections are provided with key surfaces.

An expedient design of the tensioning drive is characterized according to claim 7 characterized in that the thickened 1st end, the constrictions and the Peripheral bead are provided directly on the threaded spindle. The threaded section the threaded spindle is provided with a longitudinal groove for receiving a Sliding spring as part of a longitudinally displaceable with a clamping nut Pressure piece of the tensioning drive provided. To reduce the frictional forces between the Is clamping nut and the pressure piece to a minimum, is this in a sleeve-like extension of the clamping nut an axial thrust bearing arranged on which the pressure piece comes to rest.

The pressure piece is advantageous according to claim 8 with a spherical segment-shaped Pressure surface for engagement in a correspondingly concave configured Dome on the periphery of a central opening in the 2nd clamping plate Provided. In this way, relative pivoting movements between the loaded by the helical compression spring 2nd clamping plate and the Pressure piece to be taken into account. The calotte is located on the 2. end facing outside of the 2nd clamping plate.

To space problems when tensioning a helical compression spring in the field of Slotted 1. Spandeller effectively counteract, see the Features of claim 9 in an advantageous embodiment of the invention before that the 1st clamping plate on the side facing away from the calotte with a footprint for a spring coil is provided whose slope in Circumferential direction of the 1st clamping plate of the pitch of the helical compression spring is aligned. Furthermore, it is important in this context that the vorsprunglos in the outer periphery of the 1st clamping plate passing Contact patch to the inner end of the transverse slot through a in the Spring-winding annular bead is limited. That is, the spring coil not on the outer circumference of the 1st clamping plate of a provided there Edge is embraced, but only on the inner circumference properly on Ring bead is centered.

The second clamping plate is facing away from the calotte according to claim 10 Inside provided with a footprint for a spring coil whose Incline in the circumferential direction of the second clamping plate of the pitch of the helical compression spring is aligned, the vorläufungslos in the outer periphery of the 2. Spandeller passing footprint to the center axis of the second clamping plate is limited by a holding in a spring coil annular bead. Also here on the 2nd clamping plate the helical compression spring is through the Ring bead a perfect centering.

It is particularly advantageous if according to claim 11, the central axis of the Ring bulge to the common center axis of the second clamping plate and the central opening facing away from the peripheral recess Direction is offset. This is also in constricted spatial Conditions facilitates the handling of the inner tensioner.

Figur 1

die Einzelteile eines Innenspanners zum Spannen einer Schraubendruckfeder, teilweise in schematischer Perspektive, teilweise in schematischer Ansicht;

Figur 2

in schematischer Seitenansicht einen Längenabschnitt des Innenspanners der Figur 1 in montiertem Zustand;

Figur 3

einen Längsschnitt durch die Darstellung der Figur 2 entlang der Linie III-III in Richtung der Pfeile IIIa gesehen;

Figur 4

eine Ansicht auf die Innenseite eines 2. Spanntellers des Innenspanners der Figur 1;

Figur 5

eine Seitenansicht des 2. Spanntellers gemäß dem Pfeil V der Figur 4;

Figur 6

einen Querschnitt durch den 2. Spannteller der Figur 4 entlang der Linie VI-VI in Richtung der Pfeile VIa gesehen;

Figur 7

in der Ansicht einen weiteren Längenabschnitt des Innenspanners der Figur 1 vor der Kopplung mit einem 1. Spannteller;

Figur 8

eine Draufsicht auf die Darstellung der Figur 7 in Richtung des Pfeils VIII gesehen;

Figur 9

eine Ansicht auf die Innenseite des 1. Spanntellers des Innenspanners der Figur 1;

Figur 10

in der Perspektive den 1. Spannteller von der Außenseite her betrachtet und

Figur 11

eine Seitenansicht des 1. Spanntellers der Figur 9 in Richtung des Pfeils XI gesehen.

The invention is explained in more detail with reference to exemplary embodiments illustrated in the drawings. Show it:

FIG. 1

the items of an internal tensioner for tensioning a helical compression spring, partially in schematic perspective, partially in schematic view;

FIG. 2

in a schematic side view of a longitudinal section of the inner tensioner of Figure 1 in the assembled state;

FIG. 3

a longitudinal section through the representation of Figure 2 along the line III-III seen in the direction of the arrows IIIa;

FIG. 4

a view of the inside of a second clamping plate of the inner tensioner of Figure 1;

FIG. 5

a side view of the second clamping plate according to the arrow V of Figure 4;

FIG. 6

a cross section through the 2nd Spandeller of Figure 4 along the line VI-VI seen in the direction of the arrows VIa;

FIG. 7

in the view of a further longitudinal section of the inner tensioner of Figure 1 prior to coupling with a first clamping plate;

FIG. 8

a plan view of the representation of Figure 7 seen in the direction of arrow VIII;

FIG. 9

a view of the inside of the first clamping plate of the inner tensioner of Figure 1;

FIG. 10

in the perspective of the 1st Spannteller seen from the outside and

FIG. 11

a side view of the first clamping plate of Figure 9 seen in the direction of arrow XI.

With 1 in Figure 1 is generally an internal tensioner for tensioning a helical compression spring 2 designates, as for example for disassembly and Assembly of a helical compression spring 2 is used, the component the chassis of a motor vehicle forms.

The inner tensioner 1 is composed of a tensioning drive 3 with threaded spindle 4, pressure piece 5 and clamping nut 6 and two with the tensioning drive. 3 coupled clamping plates 7, 8 together.

The recognizable from Figures 1 to 3, 7 and 8 threaded spindle 4 has over most of its length a threaded portion 9 with a rectangular thread 10 (Figure 3). Front side of the threaded portion 9 is a axial projection 11 with key surfaces 12 for applying a tool.

The threaded portion 9 is parallel to the longitudinal axis 13 of the Threaded spindle 4 penetrated by a longitudinal groove 14. The longitudinal groove 14 is used the engagement of a sliding spring 15, which is located in the pressure piece 5 (FIGS 1 to 3). The pressure piece 5 can slide over the threaded portion 9. It lies with a ring gear 16 on a thrust bearing 17, which is inserted into the clamping nut 6 is (Figure 3). In the figure 1, the thrust bearing 17 is not shown. The Clamping nut 6 can via key surfaces 18 by means of a suitable Tool are displaced along the threaded portion 9.

At the other end, the pressure piece 5 has a spherical segment-shaped Convex pressure surface 19 for engaging in a correspondingly concave configured Dome 20 in the outer side 21 of the second clamping plate 8 circumferentially one central aperture 22 (Figures 1 to 6).

On the side facing away from the dome 20 inside 23 of the second clamping plate 8 with a vorsprungslos in the outer periphery 24 of the second clamping plate 8 passing Footprint 25 provided. The slope of the footprint 25 corresponds approximately to the pitch of the helical compression spring 2. To the central axis 26 of the second clamping plate 8 towards the footprint 25 by a torus 27 limited. The annular bead 27 goes over a concave throat 28 in the Footprint 25 via.

The footprint 25 is interrupted by a peripheral recess 29. This circumferentially on the angle α extending recess 29th serves the passage of the spring wire of the helical compression spring 2 of the Inside 23 on the outside 21 of the second clamping plate 8. The recess 29 circumferentially bounding surfaces 30 extend in radial planes, which intersect the central axis 31 of the annular bead 27. These Central axis 31 is to the common center axis 26 of the second clamping plate 8 and the central opening 22 by a dimension X in the recess 29th offset direction away.

The threaded portion 9 of the threaded spindle 4 is according to the particular Figures 7 and 8 in a shaft-like longitudinal section 32 via. This one points a constriction 33, which is followed by a circumferential bead 34. Between the bulge 34 and a thickened 1st end 35 of the Threaded spindle 4 is another constriction 36. The diameter D of the constrictions 33, 36 is sized equal.

The first end 35 is formed hemispherical to the threaded portion 9. His level end face 37 is on the circumference of straight edges 38 and circular section-shaped Transition edges 39 limited. From the straight edges 38 from spherical section-shaped surfaces 40 extend in the direction of Longitudinal axis 13 of the threaded spindle 4. Narrow spherical segment-shaped Surfaces 41 extend from the circular section-shaped transition edges 39 in the direction of the longitudinal axis 13. The radius R of the surfaces 40th between the straight edges 38 and the longitudinal axis 13 is greater than that Radius R1 of the surfaces 41 between the transition edges 39 and the Longitudinal axis 13 dimensioned. The circumferentially of the first end 35 measured length of the surfaces 40 corresponds to the larger radius R. about six times the length of the surfaces 41 with the smaller one Radius R1.

Front side of the first end 35 is an axial projection 42 with key surfaces 43rd provided for attaching a tool.

With the thickened 1st end 35 of the threaded spindle 4 is the 1st clamping plate. 7 coupled, which is more apparent from Figures 1 and 9 to 11. The 1. Clamping plate 7 has a transverse slot 44, the inner end 45 of a circular section is trained. Circumference of the inner end 45 is adjacent the outer side 46 a cap 47 is formed, which with with the Configuration of the surfaces 40, 41 of the 1st end 35 aligned spherical segment-shaped wider inner surfaces 48 and the other hand narrower inner surfaces 49 is equipped. The radius of all inner surfaces 48, 49 of the cap 47 corresponds to the radius R of the surfaces 40 between the straight edges 38 and the longitudinal axis 13 at the first end 35. The wide Inner surfaces 48 open over straight edges 59 and the other hand narrower inner surfaces 49 via circular section-shaped transition edges 60th in the outer side 46 of the 1st clamping plate. 7

Furthermore, Figures 1, 9 and 11 show that the first clamping plate 7 is open the calotte 47 facing away from inside 50 with a vorsprungslos in the Outer circumference 51 transition footprint 52 for a spring coil 53rd the helical compression spring 2 is provided whose pitch in the circumferential direction of the 1st clamping plate 7 of the slope of the helical compression spring 2 is aligned. The footprint 52 is to the central axis 54 of the clamping plate 7 out through limited to a spring coil 53 annular bead 55. The the Annular bead 55 interrupting recess 56 on the circumference of the clamping plate. 7 serves the passage of the spring wire of the helical compression spring 2 of the Outside 56 on the inside 50. It extends over an angle β of about 90 ° between the surfaces 57. The surfaces 57 extend in Radial planes that intersect the central axis 54 of the first clamping plate 7.

The diameter D of the constrictions 33, 36 on the shaft-like longitudinal section 32 of the threaded spindle 4 is smaller than the width B of the transverse slot 44 sized in the 1st clamping plate 7. The diameter D1 of the Peripheral bead 34 is greater than the width B of the transverse slot 44, however smaller than the diameter D2 of the circular section-shaped inner end 45 the transverse slot 44 (Figures 7, 8 and 9).

1. Spannteller 7 und dem 2. Spannteller 8 axial gespannt, das heißt verkürzt werden. Die Schraubendruckfeder 2 ist hierbei durch die Ringwulste 27 und 55 exakt lagefixiert.

To tighten the helical compression spring 2, the second clamping plate 8 is first inserted transversely between two spring coils 53 in the vicinity of the second end 58 of the threaded spindle 4. Subsequently, the threaded spindle 4 is pushed in the longitudinal direction of the helical compression spring 2 through the central opening 22 of the second clamping plate 8 and then provided with the pressure piece 5 and the clamping nut 6. Subsequently, the first clamping plate 7 is also threaded transversely between two spring coils 53 of the helical compression spring 2, wherein the constriction 33 sums in the transverse slot 44. Thereafter, the threaded spindle 4 can be displaced in the longitudinal direction, wherein the peripheral bead 34 slides through the inner end 45 of the transverse slot 44 until the first end 35 sums in the cap 47 of the first clamping plate 7. Now, by turning the clamping nut 6, the helical compression spring 2 between the

1. Spannteller 7 and the second clamping plate 8 axially tensioned, that is shortened. The helical compression spring 2 is in this case exactly fixed in position by the annular beads 27 and 55.

REFERENCE NUMBERS

1 -

interior tensioner

2 -

Helical compression spring

3 -

tensioning drive

4 -

screw

5 -

Pressure piece

6 -

locknut

7 -

1st clamping plate

8th -

2. Spannteller

9 -

threaded portion

10 -

square thread

11 -

Lead at 9

12 -

Wrench flats at 11

13 -

Longitudinal axis v. 4

14 -

Longitudinal groove in 9

15 -

Sliding spring in 5

16 -

Ring wreath v. 5

17 -

Thrust bearing in 6

18 -

Wrench flats to 6

19 -

Printing area at 5

20 -

Dome in 8

21 -

Outside v. 8th

22 -

Front side v. 8th

23 -

central opening in 8

24 -

Outer circumference v. 8th

25 -

Footprint on 8

26 -

Central axis v. 8th

27 -

Ring bulge at 8

28 -

Throat between 27 and 25

29 -

Recess in 8

30 -

Areas v. 29

31 -

Central axis v. 27

32 -

shaft-like length v. 4

33 -

Constriction at 32

34 -

Circumferential bead at 32

35 -

thickened 1st end v. 4

36 -

Constriction at 32

37 -

Front side v. 35

38 -

straight edges on 37

39 -

Transitional edges on 37

40 -

spherical segment-shaped surfaces at 35

41 -

spherical segment-shaped surfaces at 35

42 -

Lead at 35

43 -

Key areas on 42

44 -

Transverse slot in 7

45 -

inner end v. 44

46 -

Outside v. 7

47 -

Dome in 7

48 -

wide interior surfaces v. 47

49 -

narrow inner surfaces v. 47

50 -

Inside v. 7

51 -

Outer circumference v. 7

52 -

Contact patch at 7

53 -

Spring winding v. 2

54 -

Central axis v. 7

55 -

Ring bulge at 7

56 -

Recess at 7

57 -

Areas v. 56

58 -

2nd end of v. 4

59 -

straight edges v. 48

60 -

Transitional edges v. 49

B -

Width v. 39

D -

Diameter v. 28, 31

D1 -

Diameter v. 29

D2 -

Diameter v. 40

R -

Radius v. 35, 43, 44

R1 -

Radius v. 36

α -

Angle between 30

β -

Angle between 57

x -

Displacement v. 31 to 26

Claims (9)

Inner tensioner for tensioning a helical compression spring (2), in particular as a component of a chassis of a motor vehicle, which has a tensioning drive (3) with integrated threaded spindle (4) and two clamping plates (7, 8) which can be displaced relative to each other,
characterized in that the tensioning drive (3) has a thickened first end (30) with spherical-segment-shaped surfaces (35, 36) for engagement in a central dome (42) of a transversely slotted first tensioning plate (7), the dome (42 ) is equipped with ball-shaped inner surfaces (43, 44) adapted to the configuration of the surfaces (35, 36). Inner tensioner according to claim 1, characterized in that the first end (30) of the tensioning drive (3) is formed hemispherical and its flat end face (32) on the periphery of straight edges (33) and circular section-shaped transition edges (34) is limited, from which the spherical segment-shaped surfaces (35, 36) extend in the direction of the longitudinal axis (13) of the tensioning drive (3), the radius (R) of the surfaces (35) between the straight edges (33) and the longitudinal axis (13) being greater than Radius (R1) of the surfaces (36) between the transition edges (34) and the longitudinal axis (13) is dimensioned, and that the radius of the inner surfaces (43, 44) of the dome (42) to the radius (R) of the surfaces (35) between the straight edges (33) and the longitudinal axis (13). Inner tensioner according to claim 1 or 2, characterized in that the length of the larger radius surfaces (R) measured in the circumferential direction of the first end (30) is approximately six times the length of the smaller radius surfaces (36). R1) corresponds. Inner tensioner according to one of claims 1 to 3, characterized in that the inner surfaces (43, 44) of the dome (42) with straight edges (50) and circular transition edges (51) in the dome (42) adjacent end face (41) of 1.Spanntellers (7) open. Inner tensioner according to one of claims 1 to 4, characterized in that on a shaft-like longitudinal portion (27) of the tensioning drive (3) adjacent to the first end (30) two by a peripheral bead (29) from each other separate constrictions (28, 31) are provided whose diameter (D) is smaller than the width (B) of the transverse slot (39) in the first spider (7), the diameter (D1) of the circumferential bead (29) being greater than the width (B) of the transverse slot (39 ), but smaller than the diameter (D2) of the circular portion-shaped inner end (40) of the transverse slot (39). Inner tensioner according to one of claims 1 to 5, characterized in that projections (37, 11) with key surfaces (38, 12) are provided on the first end (30) and / or on the second end (52) of the tensioning drive (3) , Inner tensioner according to claim 5 or 6, characterized in that the thickened 1st end (30), the constrictions (28, 31) and the peripheral bead (29) directly to the threaded spindle (4) of the clamping drive (3) are provided and the threaded portion (9) of the threaded spindle (4) with a longitudinal groove (14) for receiving a sliding spring (15) as part of a with a clamping nut (6) along the threaded portion (9) displaceable pressure piece (5) is provided. Inner tensioner according to claim 7, characterized in that the pressure piece (5) with a spherical segment-shaped pressure surface (19) for engagement in a correspondingly configured dome (20) is peripherally provided on a central opening (21) in the 2.Spannteller (8). Inner tensioner according to one of claims 1 to 8, characterized in that the 1.Spannteller (7) on the dome (42) facing away from front side (45) with a contact surface (46) for a spring coil (24) is provided, the slope in Circumferential direction of the 1.Spanntellers (7) of the pitch of the helical compression spring (2) is aligned, wherein the footprint (46) to the axis (47) of the clamping plate (7) through a limited in a spring coil (24) annular section-shaped bead (48) limited is.

Images