LINEAR UNIT

Abstract

The disclosure relates to a linear unit for a flap arrangement with a flap, and a closed position, wherein the linear unit has two drive connections which are coupled to each other via a gearing and are adjustable relative to each other along a geometrical linear axis, wherein the linear unit has a helical spring arrangement, wherein the helical spring arrangement has a first spring element which is configured as a helical spring and a second spring element which is configured as a helical spring, with which helical springs the two drive connections can be pretensioned against each other, wherein the second spring element is oriented coaxially with respect to the first spring element with regard to a geometrical spring axis. It is proposed that the spring wire at one end of the second spring element forms a supporting portion via which the first spring element secures the second spring element axially.

Claims

1. A linear unit for a flap arrangement with a flap which is adjustable between an open position and a closed position, wherein the linear unit has two drive connections which are coupled to each other via a gearing and are adjustable relative to each other along a geometrical linear axis, wherein the linear unit has a helical spring arrangement, wherein the helical spring arrangement has a first spring element which is configured as a helical spring and is made from spring wire and a second spring element which is configured as a helical spring and is made from spring wire, with which helical springs the two drive connections can be pretensioned against each other, wherein the second spring element is oriented coaxially with respect to the first spring element with regard to a geometrical spring axis, wherein the spring wire at one end of the second spring element forms a supporting portion via which the first spring element secures the second spring element axially with regard to the spring axis.

2. The linear unit according to claim 1, wherein the second spring element is arranged within the first spring element.

3. The linear unit according to claim 1, wherein the helical spring arrangement pushes the two drive connections apart, and/or wherein the two spring elements are each configured as helical compression springs.

4. The linear unit according to claim 1, wherein the gearing has a spindle/spindle-nut gearing.

5. The linear unit according to claim 1, wherein the linear unit has a motorized drive for producing drive movements along the linear axis, and wherein, when the linear unit is fitted, the flap arrangement is adjustable in a motorized manner by the linear unit.

6. The linear unit according to claim 1, wherein the drive train between the drive connections and the gearing is not configured to be self-locking.

7. The linear unit according to claim 1, wherein the first spring element is otherwise in engagement in a force-fitting manner with the linear unit over the entire adjustment range of the linear unit, and wherein the second spring element is otherwise in engagement in a force-fitting manner with the linear unit only over a partial adjustment range.

8. The linear unit according to claim 1, one of the preceding claims, wherein, in the fitted state, the second spring element acts with its spring pretensioning on the flap only over a partial adjustment range of the flap.

9. The linear unit according to claim 1, wherein, in the fitted state, the second spring element is shorter than the first spring element.

10. The linear unit according to claim 1, wherein the linear unit has a receiving surface for receiving the spring arrangement, and wherein the supporting portion is secured by axial clamping between the first spring element and the receiving surface.

11. The linear unit according to claim 1, wherein the supporting portion has at least one portion of a supporting winding which is secured by axial clamping between the first spring element and the receiving surface.

12. The linear unit according to claim 1, wherein the winding pitch of the supporting portion is lower than the winding pitch of the second spring element.

13. The linear unit according to claim 1, wherein the supporting portion extends with regard to the spring axis over an angular range of at least 60.

14. The linear unit according to claim 1, wherein the central winding diameter of the supporting winding of the second spring element is greater than the outer winding diameter of the second spring element otherwise, wherein the inner winding diameter of the supporting winding of the second spring element is greater than the outer winding diameter of the second spring element otherwise.

15. The linear unit according to claim 1, wherein, for the axial securing, the first spring element acts on the supporting portion over an angular range of at least 60 with regard to the spring axis.

16. A flap arrangement with a flap which is adjustable between an open position and a closed position, and with a linear unit according to claim 1 which is coupled to the flap in terms of drive.

17. The linear unit according to claim 4, wherein the spindle/spindle-nut gearing is arranged within the first spring element.

18. The linear unit according to claim 8, wherein, in the fitted state, the second spring element acts with its spring pretensioning on the flap only over a partial adjustment range of the flap, which partial adjustment range is limited by the closed position of the flap.

19. The linear unit according to claim 11, wherein the supporting winding has a helical or spiral or circular-section profile.

20. The linear unit according to claim 12, wherein the winding pitch of the supporting element is smaller than 10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The disclosure is explained in more detail below with reference to a drawing which illustrates merely one exemplary embodiment. In the drawing

[0034] FIG. 1 shows an exemplary embodiment of a flap arrangement according to the proposal with a linear unit according to the proposal, and the linear unit in an enlarged, three-dimensional illustration,

[0035] FIG. 2 shows an exemplary embodiment of a linear unit according to the proposal in a) an extended state and in b) a retracted state,

[0036] FIG. 3 shows an exemplary embodiment of the helical spring arrangement of a linear unit according to the proposal, and

[0037] FIG. 4 shows an exemplary embodiment of the helical spring arrangement from FIG. 3 in an exploded illustration.

DETAILED DESCRIPTION

[0038] FIG. 1 shows a flap arrangement 1 according to the proposal which is adjustable between an open position and a closed position. With regard to the definition of the terms flap and flap arrangement, reference is made to the introductory part of the description.

[0039] The flap arrangement 1 which is shown has a linear unit 2 according to the proposal which is coupled in terms of drive to the flap 3. Here, the flap arrangement 1 has two linear units 2 according to the proposal. In the exemplary embodiment, said linear units serve for adjusting the flap 3 from a closed position into an, in particular completely opened, open position and/or from an, in particular completely opened, open position into a closed position.

[0040] The linear unit 2 according to the proposal has two drive connections 4, 5. The latter serve in particular for introducing a force into the flap 3 for opening and/or for closing same. The drive connections 4, 5 are coupled to each other via a gearing 6 and are adjustable relative to each other along a geometrical linear axis A. The gearing 6 here is designed as a spindle/spindle-nut gearing. It serves here for converting drive movements along the linear axis A.

[0041] Furthermore, the linear unit 2 has, according to the proposal, a helical spring arrangement 7. The helical spring arrangement 7 has a first spring element 8 which is configured as a helical spring and is made from spring wire, and a second spring element 9 which is configured as a helical spring and is made from spring wire. The two drive connections 4, 5 can be pretensioned against each other by means of the helical spring arrangement 7, as can be gathered from the illustration according to FIG. 2. In some embodiments, as shown in FIG. 2, in the fitted state the second spring element 9 is shorter than the first spring element 8.

[0042] With regard to a geometrical spring axis B, the second spring element 9 is oriented coaxially with respect to the first spring element 8 and can be arranged within the first spring element 8. The spring axis B is formed coaxially with respect to the linear axis A here. In order to permit simple installation and to fix the second spring element 9 securely in the linear unit 2, the spring wire at one end 10 of the second spring element 9 forms a supporting portion 11 via which the first spring element 8 secures the second spring element 9 axially with regard to the spring axis B. By this means, during the installation of the linear unit 2, the second spring element 9 can simply be inserted into the first spring element 8 and can be permanently secured axially by the further installation of the linear unit 2. As a result, there is no longer the risk of the second spring element 9 loosening, for example, from a clip connection or the like. Undesirable noises during the opening and/or the closing of the flap 3 due to a second spring element 9 sliding around, because it has been loosened, can be permanently avoided.

[0043] Here, the helical spring arrangement 7 pushes the two drive connections 4, 5 apart. The two spring elements 8, 9 can each be designed here as helical compression springs. Here, in the fitted state of the flap arrangement 1, the first spring element 8 pushes the drive connections 4, 5 apart over the entire adjustment range of the flap 3 while, in the fitted state of the flap arrangement 1, the second spring element 9 pushes the drive connections 4, 5 apart only over a partial adjustment range of the flap 3.

[0044] In an advantageous manner, the coil of the spiral of the first spring element 8 and the coil of the spiral of the second spring element 9 can be oriented in the same direction, as is shown in the figures. Alternatively, however, they can also be oriented in opposite directions.

[0045] In the exemplary embodiment, the gearing 6 is designed as a spindle/spindle-nut gearing. It has a spindle 12 and a nut 13. The spindle/spindle-nut gearing is arranged here within the first spring element 8. It serves for converting drive movements along the linear axis A. Here, the spindle 12 is separated from the spring arrangement by a tube.

[0046] According to the configuration of the linear unit 2 that is shown in FIGS. 1 and 2, said linear unit has a motorized drive 14 for producing drive movements along the linear axis A. Here, the drive 14 is arranged at that end of the linear unit 2 which lies opposite the second spring element 9. In order to produce the drive movement, the rotational movement of the motorized drive 14 can be converted into a linear movement by the gearing 6. In this manner, when the linear unit 2 is fitted, the flap arrangement 1 can be adjusted in a motorized manner by means of the linear unit 2. It can be possible to move the flap 3 in a motorized manner with the linear unit 2 or the linear units 2 from a closed position, in particular a preliminary latching closed position, into an, in particular completely opened, open position and/or from an, in particular completely opened, open position into a closed position, in particular into a preliminary latching closed position.

[0047] The first spring element 8 can secure the supporting portion 11 of the second spring element 9 in direct contact here.

[0048] In the present case, in order to produce the drive movement along the linear axis A, the motorized drive 14 is coupled, optionally via a reduction gearing 15, to the spindle/spindle-nut gearing, in particular to the spindle 12 of the spindle/spindle-nut gearing.

[0049] The drive train 16 between the drive connections 4, 5 and the gearing 6 can be not configured to be self-locking. It should be noted here that, in order to form a drive train 16 between the two drive connections 4, 5, the linear unit 2 does not necessarily have to have a motorized drive 14. The force in the drive train 16 for opening the flap 3 can also be provided, for example, solely by the pretensioning of the helical spring arrangement 7.

[0050] As can be gathered from the illustration according to FIG. 2, the linear unit 2 can be retracted and extended along the linear axis A. While said linear unit is shown in FIG. 2a in an extended state, it is shown in a retracted state in FIG. 2b. As is furthermore shown in FIG. 2a, here, the first spring element 8 is otherwise in engagement in a force-fitting manner with the linear unit 2 over the entire adjustment range of the linear unit 2.

[0051] By contrast, the second spring element 9 is otherwise in engagement in a force-fitting manner with the linear unit 2 only over a partial adjustment range, in particular over a partial adjustment range which is located at one end of the overall adjustment range.

[0052] In a configuration, in the fitted state, the second spring element 9 acts with its spring pretensioning on the flap 3, in particular in the opening direction thereof, only over a partial adjustment range of the flap 3, as illustrated in FIG. 2b. Here, said partial adjustment range is limited by the closed position of the flap 3. By this means, the helical spring arrangement 7 can provide a particularly large force in the opening direction of the flap 3 in the region in which the lever ratios for the opening of the flap arrangement 1 are particularly unfavourable. Such a spring element 9 is a pop-up spring, as has been explained further above.

[0053] In a further partial adjustment range of the flap 3, the second spring element 9 does not act with spring pretensioning of the flap 3, as emerges from the illustration according to FIG. 2. In said further partial adjustment range, the second spring element 9 is substantially relaxed. Here, said further partial adjustment range of the flap 3 extends over a smaller flap opening angular portion than the partial adjustment range in which the second spring element 9 acts with its spring pretensioning on the flap 3.

[0054] As a result of the fact that the second spring element 9 acts only in a partial adjustment range in the linear unit 2, said second spring element is not secured by its pretensioning over the entire adjustment range. Axial securing of said spring element is therefore required so that it can be held over the entire adjustment range. Otherwise, the second spring element 9 could move during the adjustment in the linear unit 2 and produce undesirable noises. In order specifically to avoid this, the clamping according to the proposal is a particularly good structural solution in particular for such a pop-up spring design of the second spring element 9.

[0055] The linear unit 2 furthermore has a receiving surface 17 for receiving the spring arrangement 7. Between said receiving surface and the first spring element 8, the supporting portion 11 is secured by axial clamping, as can be gathered from FIGS. 1 and 2. The second spring element 9 can thereby be secured in a particularly simple manner. Here, the receiving surface 17 is provided by a drive connection 4.

[0056] The second spring element 9 can have one or more dead windings, in particular in a region on or shortly before the supporting portion 11. This permits centring of the first spring element 8, in particular this permits centring of that end of the first spring element 8 which secures the supporting portion 11. In addition, in particular in order to reduce noise, the first spring element 8 and/or the second spring element 9 can be at least partially flocked. By this means, noises which could arise due to windings of the first spring element 8 and of the second spring element 9 butting against each other or rubbing against each other during the adjustment of the linear unit 2 can be avoided or reduced.

[0057] In an open position of the flap 3, that end of the second spring element 9 which faces away from the supporting portion 11 can be free, as illustrated in FIG. 2a. The linear unit 2 can have an, in particular L-shaped, supporting element 19, onto which that end of the second spring element 9 which faces away from the supporting portion 11 runs and against which the second spring element 9 is braced when the flap 3 is moved into a closed position. As shown in FIG. 1, in the fitted state of the linear unit 2, the first spring element 8 can be supported with its end facing away from the supporting portion 11 on the supporting element 19. The first spring element 8 and the second spring element 9 can be supported on different surfaces of the supporting element 19, said surfaces here being arranged offset in the direction of the linear axis A.

[0058] In order to form a supporting surface 18, the supporting portion 11 can be ground at the second spring element 9. This increases the contact surface between the receiving surface 17 and the supporting surface 18. Additionally or alternatively, that surface of the first spring element 8 which faces the receiving surface 17 can also be ground in order to form a supporting surface 8a. This also increases the abutment surface and achieves better contact between first spring element 8 and the supporting portion 11, and therefore a more stable securing thereof.

[0059] As can be gathered from the illustration according to FIG. 2, the supporting portion 11 has a supporting winding 20 which is secured by axial clamping between the first spring element 8 and the receiving surface 17. The supporting winding 20 can have a helical or spiral or circular-section profile. The supporting portion 11, in particular the supporting winding 20, can extend over an angular range of at least 60, such as at least 90, furthermore such as at least 180, furthermore such as at least 270, with regard to the spring axis B. The term supporting winding should therefore be broadly understood as meaning that the supporting winding 20 does not have to completely encircle the spring axis B. However, as indicated by dashed lines in FIG. 4, the supporting winding 20 can also extend with regard to the spring axis B over an angular portion of more than 360, in particular if said supporting winding is of spiral design.

[0060] Furthermore, the supporting portion 11, in particular if it has a circular-section profile, can have a transition portion 21 via which the winding diameter of the second spring element 9 is increased in order to form the supporting winding 20. It should furthermore be pointed out that the supporting winding 20 can have a plurality of portions, wherein the supporting winding portions can have a profile of differing shape. For example, one supporting winding portion can have a helical profile while a further supporting winding portion can have a spiral profile. Furthermore, the supporting winding portions can also have other combinations of profiles. The supporting winding portions together can form a combination of a helical and/or spiral and/or circular-section profile.

[0061] Here, the central winding diameter DA of the supporting winding 20 of the second spring element 9 is larger than the outer winding diameter D.sub.IIa of the second spring element 9 otherwise. In the exemplary embodiment and furthermore, the inner winding diameter D.sub.Ai of the supporting winding 20 of the second spring element 9 can be larger than the outer winding diameter D.sub.IIa of the second spring element 9 otherwise. In this case, the transition portion from the rest of the second spring element 9 is not included.

[0062] Furthermore, the central winding diameter DA of the supporting winding 20 substantially corresponds over a substantial portion to the central winding diameter Di of the first spring element 8. By this means, a particularly stable abutment can be formed for the first spring element 8 in order to secure the second spring element 9.

[0063] As shown in FIG. 4, in the untensioned state of the second spring element 9, the winding pitch SA of the supporting portion 11, in particular of the supporting winding 20, here is lower than the winding pitch S.sub.II of the second spring element 9 otherwise. In the untensioned state of the second spring element 9, the winding pitch of the supporting portion 11 here is smaller than 10, furthermore smaller than 5. In a configuration, the winding pitch of the supporting portion 11 can be substantially 0. Here, the winding pitch is defined as the pitch of the spiral of the second spring element 9 with respect to a plane orthogonal to the spring axis B.

[0064] In order to further improve the securing of the supporting portion 11, for the axial securing, the first spring element 8 acts on the supporting portion 11, in particular the supporting winding 20, over an angular range of at least 60, or at least 90, with regard to the spring axis B. In order to achieve a particularly stable securing of the second spring element 9 and also to particularly effectively counteract tilting tendencies of the second spring element 9, it is possible, as in the exemplary embodiment, in particular shown in FIGS. 2 and 3, for the axial securing, for the first spring element 8 to act on the supporting portion, in particular the supporting winding, over an angular range of at least 180, or furthermore at least 270, with regard to the spring axis B. In the event of securing over 270, a particularly stable supporting and securing of the second spring element 9 is achieved in all directions of inclination.

[0065] A centring element, in particular made from plastic, can be provided on the supporting portion 11, in particular on the supporting winding 20. Said centring element can centre the first spring element 8 and/or the second spring element 9, in particular at one of the ends thereof. Additionally or alternatively, a buffer element, can be made from plastic, can be provided on the supporting portion 11, in particular the supporting winding 20, said buffer element reducing the pressing of the supporting portion by the first spring element 8. Particularly, the centring element and the buffer element are formed integrally.

[0066] Finally, it should be pointed out that the linear unit 2 can have an, in particular telescopic, housing 22 for protecting said linear unit from environmental influences. The drive connections 4, 5 can form a cover of said housing 22, as a result of which particularly simple installation is ensured.