Spring arm sleeve

Abstract

A spring arm sleeve, with which a joining element of a joining device is positionable and which comprises the following features: a tubular section which is formed by a circumferential or all-round wall, the circumferential wall comprises in the circumferential direction a plurality of U-shaped apertures regularly spaced apart from one another, which form a plurality of one-sidedly fastened spring arms which are inclined radially inwards into the tubular section and extend from a fixed end in a first longitudinal direction.

Claims

1. A spring arm sleeve with which a joining element of a joining device is positionable and which comprises the following features: a. an entry end, an exit end and a tubular section which is formed by a circumferential wall, wherein the tubular section defines a first longitudinal direction, b. the circumferential wall comprises in a circumferential direction a plurality of U-shaped apertures regularly spaced from one another, c. wherein the plurality of apertures forms a plurality of one-sidedly fastened spring arms which are inclined radially inwards into the tubular section, in which d. in the first longitudinal direction of the tubular section, d1. at a first length at least three spring arms are arranged in the circumferential direction evenly spaced from one another and d2. at at least one second length different from the first length at least three spring arms are arranged in the circumferential direction evenly spaced from one another, wherein e. the first and the second length are measured between the entry end of the spring arm sleeve and a center of the respective spring arms and f. each spring arm extends toward the exit end starting from a respective fixed end in the first longitudinal direction; wherein the at least three spring arms of the second length are arranged at circumferential positions which are located between the at least three spring arms of the first length, and the first length and the second length as well as a length of the spring arms are selected in such a manner that the spring arms of the first length and the spring arms of the second length overlap each other in the longitudinal direction of the tubular section.

2. The spring arm sleeve according to claim 1, in which the tubular section comprises a round or polygonal cross-section.

3. The spring arm sleeve according to claim 1, in which the tubular section comprises a cross-section of a regular at least hexagonal even polygon, in which the spring arms of the first and the second length are arranged at every other side.

4. The spring arm sleeve according to claim 1, which is comprised of at least two axial sleeve sections which are arranged axially adjacent to each other.

5. The spring arm sleeve according to claim 1, which comprises at one of the entry and the exit end or at the entry and the exit end regularly arranged clearances adjacent to strip shaped end portions.

6. The spring arm sleeve according to claim 5, which is comprised of at least two sleeve sections, wherein axial ends of the at least two sleeve sections have the regularly arranged clearances and the adjacent strip shaped end portions arranged in a nested manner.

7. The spring arm sleeve according to claim 1, in which the circumferential wall is formed closed.

8. The spring arm sleeve according to claim 1, in which the circumferential wall is formed discontinuously.

9. A joining device with a mouthpiece, wherein a spring arm sleeve according to claim 1 is arranged inside the mouthpiece.

10. The joining device according to claim 9, in which the mouthpiece comprises a joining channel which, adjacent to an end in a joining direction, comprises a radially inwardly projecting retaining collar on which the spring arm sleeve is supported in the axial direction.

11. A manufacturing method for a spring arm sleeve according to claim 1, comprising the following steps: a. providing a planar element with a plurality of U-shaped apertures regularly spaced from one another, which form a plurality of one-sidedly fastened spring arms which extend starting from a fixed end in a first longitudinal direction, b. deforming the planar element into a tubular section which defines a passage channel; and c. deforming the spring arms radially inwards into the passage channel so that they are arranged in an inclined manner.

12. The manufacturing method according to claim 11, in which the planar element is a spring sheet which is laser cut or etched or punched.

13. The manufacturing method according to claim 12, in which the tubular section is deformed in such a manner that it comprises a hexagonal or octagonal uniform cross-section.

14. The manufacturing method according to claim 11, in which the planar element is a plastic element which is laser cut or etched or punched.

Description

4. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

(1) The embodiments of the present disclosure are described in more detail with reference to the accompanying drawings. Showing:

(2) FIG. 1 an exemplary schematic illustration of an element feed of a joining device, in which an embodiment of the spring arm sleeve is arranged in the joining channel or in the mouthpiece,

(3) FIG. 2 a sectional view through a joining channel with a spring arm sleeve arranged therein according to an embodiment,

(4) FIG. 3 a perspective view of a spring arm sleeve,

(5) FIG. 4 a radial sectional view of the spring arm sleeve of FIG. 3,

(6) FIG. 5 an axial sectional view of the spring arm sleeve of FIG. 3,

(7) FIG. 6 a perspective view of another embodiment of a spring arm sleeve,

(8) FIG. 7 an axial sectional view of the spring arm sleeve of FIG. 6,

(9) FIG. 8 a perspective illustration of two spring arm sleeves, which are combinable with each other as one common spring arm sleeve,

(10) FIG. 9 the spring arm sleeves of FIG. 8 in a combined arrangement, in which they may also be receivable in a joining channel of a joining device,

(11) FIG. 10 a perspective view of a further embodiment of a spring arm sleeve,

(12) FIG. 11 a radial sectional view of the spring arm sleeve of FIG. 10,

(13) FIG. 12 an illustration regarding the movement of a joining element through a spring arm sleeve,

(14) FIG. 13 a partial sectional view of an embodiment of a spring arm sleeve,

(15) FIG. 14 an enlarged view of a spring arm in an initial position,

(16) FIG. 15 an enlarged view of a spring arm in a radially outwardly deflected position; and,

(17) FIG. 16 a flow chart of an embodiment of a manufacturing method of the spring arm sleeve.

5. DETAILED DESCRIPTION

(18) The spring arm sleeve 1 may be arranged in a mouthpiece or joining channel 5 of a joining device F. FIG. 1 shows a partial view of the joining devices F, showing an element feed 7 adjacent to an entry into the joining channel 5. The sleeve-like constructed spring arm sleeve 1 (see below) is retained within the joining channel 5 such as by a radial frictional connection with the radial inner wall of the joining channel 5.

(19) According to another arrangement of the spring arm sleeve 1 in the joining channel or mouthpiece 5, the spring arm sleeve 1 is supported at a radial collar 9. The radial collar 9 can also be seen in the sectional view of FIG. 2. The radial collar 9 is arranged adjacent to the exit of the joining channel 5. Since the radial collar 9 projects into the joining channel 5 radially inwards, circumferentially continuous or all-round, it may reduce the passage openings through the joining channel 5.

(20) At this radial collar 9 an exit end 3 of the spring arm sleeve 1 is supported so that the latter cannot be pressed out of the joining channel 5 by a punch or a joining element FE during a joining process.

(21) While the spring arm sleeve 1 with the exit end 3, when viewed in the joining direction R.sub.F, is supported at the radial collar 9, it may also be preferred to fasten the spring arm sleeve 1 with an entry end 2 to the setting head SK. This fastening may be made by a frictional connection or a latching connection or a similar construction.

(22) According to a further embodiment (not shown) of the spring arm sleeve 1, the latter is directly connected to the setting head SK of the joining device F without the joining channel 5. Accordingly, the spring arm sleeve 1 replaces the joining channel 5 and ensures a reduced interference contour of the joining devices F.

(23) FIGS. 3 and 10 show perspective views of different embodiments of the spring arm sleeve 1. The spring arm sleeve 1 is formed by a circumferential or all-round wall 10 which is shaped into a tubular section 12. The tubular section 12 defines a passage channel 14, through which the joining element FE moves according to FIG. 2. The circumferential or all-round wall 10 is formed closed according to a first alternative. According to a second alternative, the circumferential or all-round wall is formed discontinuously.

(24) According to further embodiments, the tubular section 12 comprises different cross-sectional shapes. According to a design (not shown), the tubular section 12 has a round outer contour. Further, the tubular section 12 may be provided with a polygonal outer contour (see FIGS. 4 and 11). As can be seen from the further description, the outer contour has an even polygonal shape, i.e. an even number of side faces or surfaces can be seen in the cross-section of the spring arm sleeve 1. It is also possible to provide a polygonal shape with an odd number of side faces or surfaces. In FIG. 4, the polygonal cross-section has eight side faces 16 or polygonal faces, while in FIG. 11 six polygonal faces 16 can be seen.

(25) As can be seen in the perspective views, e.g. of FIGS. 3 and 10, the spring arm sleeve 1 may be constructed in a floor-like or level-like manner in the joining direction R.sub.F or viewed in longitudinal direction. In this context, a level denotes a first length L.sub.1 measured from the entry end 2 of the spring arm sleeve 1. At this first length L.sub.1 or on this first level and optionally at further following lengths L.sub.2, L.sub.3, L.sub.4 or levels, several spring arms 20 are arranged evenly distributed around the circumference of the tubular section 12. The spring arms 20 are fastened one-sidedly and arranged in an inclined manner into the passage channel 14. As it is apparent from the Figures, all spring arms 20 are arranged in an inclined manner in the joining direction R.sub.F.

(26) The spring arms 20 may be surrounded on three sides by a continuous U-shaped aperture 22 through the circumferential or all-round wall 10. Correspondingly, each spring arm 20 is connected with the wall 10 at only one side 24.

(27) An arrangement of the spring arms 20 is described with reference to the first length L.sub.1 or the first level of the spring arm sleeve 1. As can be seen from FIG. 4, the tubular section 12 may comprise the polygonal cross-section with eight polygon faces 16. At the first length L.sub.1, which may be measured at the center of the spring arm 20, a U-shaped aperture 22 and thus a spring arm 20 is arranged in the circumferential direction only on every second polygon face 16. Correspondingly, the spring arms 20 are arranged on the radially inner side of the tubular section 12 evenly distributed in the circumferential direction.

(28) On the next length L.sub.2 following in the joining direction R.sub.F or on the second level, the same number of spring arms 20 may be arranged on the radial inner side of the tubular section 12 as on the first level L.sub.1. However, the spring arms 20 of the second level or length L.sub.2 are arranged exactly at the polygon faces 16 at which no spring arms 20 are arranged in the first level L.sub.1.

(29) In addition, it may be preferred that, viewed in the joining direction R.sub.F, the spring arms 20 of the second level L.sub.2 with their connection 24 to the wall 10 already begin before an end of the spring arms 20 of the first length L.sub.1 or level is reached. In this way, a nested arrangement of the spring arms 20 of adjacent lengths L.sub.1, L.sub.2 etc. or adjacent levels results.

(30) Since the spring arms 20 of the individual levels are arranged inclined into the passage channel 14, a joining element FE moving through the passage channel 14 is retained almost continuously by the spring arms 20. This may ensure that the orientation of the joining element FE is maintained during its movement in the joining direction R.sub.F through the passage channel 14.

(31) In this context it may also be preferred to adjust the axial position and inclination of the spring arm 20 in order to achieve an optimum guidance of the joining element FE.

(32) According to a further embodiment, one spring arm 20 is provided on each polygon face 16 of the same level. Accordingly, the same arrangement of the spring arms 20 would follow on the next level in the joining direction R.sub.F. With this arrangement, there is no nested arrangement of the spring arms 20 (not shown).

(33) Furthermore, it may be preferred to leave clear at least one polygon face 16 between two adjacent spring arms 20 on adjacent levels, respectively, despite the same arrangement of the spring arms 20.

(34) In summary, it may therefore be advantageous to have at the first length L.sub.1 or on the first level and then at least the second length L.sub.2 or on the second level, at least three spring arms 20, respectively, arranged evenly spaced from each other in the circumferential direction. These at least three spring arms 20 in the first level and in the subsequent second level are arranged at equal or same circumferential positions in comparison to each other. In contrast to this, in the other design the spring arms 20 of the second level are arranged at circumferential positions at which, in the first level, precisely no spring arms 20 have been provided.

(35) FIG. 5 shows that the spring arms 20 are arranged inclined at an angle α radially inwards in the passage channel 14. The angle α may be in a range of 5°≤α≤20°, or 5°≤α≤15° or 5°≤α≤10°. Depending on a length of the spring arm 20 and its spring properties due to the selected material of the spring arm sleeve 1, the angle α is adjustable to guide and/or position and/or brake the joining element FE.

(36) According to the embodiment of the joining device F shown in FIG. 2, the spring arm sleeve 1 in the joining channel 5 is comprised of an axially continuous tubular section 12. This may be adapted to the length of the joining channel 5 or to the length of a braking and/or positioning distance.

(37) According to the embodiments shown in FIGS. 6-9, the spring arm sleeve 1 in FIG. 9 is comprised of a plurality of spring arm sleeves 1, here two spring arm sleeves 1. This construction method provides the flexibility that different lengths of joining channels 5 can be equipped with a basic spring arm sleeve 20 by multiple combinations.

(38) The basic spring arm sleeve 20 shown in FIGS. 6 and 7 comprises a nested arrangement of the spring arms 20 as has been described above. In addition, the basic spring arm sleeve 1 can comprise a polygonal cross-section with 6 or 8 or more polygon faces. This said nested arrangement of the spring arms 20 forms the basis for a stepped contour 30 of the wall 10 at the entry and/or exit end of the basic spring arm sleeve 1. The stepped contour 30 is comprised of alternating clearances 32 and strip-like end portions 34. By means of the step contour 30, several spring arm sleeves 1 can be inserted into each other and arranged in the joining channel 5. This can be seen in FIG. 1, for example, where three spring arm sleeves 1 are arranged in the joining channel 5. For this purpose, the strip-like end portions 34 of the one spring arm sleeve 1 engage in the clearances 32 of the other adjacent spring arm sleeve 1. The several spring arm sleeves 1 thus support each other in the joining channel 5.

(39) If the joining element FE moves in the joining direction R.sub.F into the entry end of the spring arm sleeve 1, as shown schematically in FIG. 12, it meets the spring arm 20. The spring arms 20 narrow the passage channel 14 with their resilient arrangement and inclination into the passage channel 14 of the tubular section 12. Accordingly, the joining element FE is first stopped and positioned in the passage channel 14 by the spring arm 20 in a clamping or frictional or non-positive manner. The uniform distribution of the spring arms 20 in the circumferential direction of the passage channel 14 ensures that the joining element FE may be arranged with its side arranged opposite to the joining direction R.sub.F, for example the head upper side of a punch rivet, parallel or at least approximately parallel to a punch underside of the punch of the joining device F. This supports a suitable positioning of the joining element FE for the joining process. While the joining element FE is moved in the joining direction R.sub.F by the spring arm sleeve 1, the spring arms 20 yield resiliently radially outwards. This is illustrated in FIGS. 14 and 15. After passing the joining element FE, the spring arms 20 spring back radially inwards to brake or decelerate and/or position the next joining element FE.

(40) With reference to the flow chart in FIG. 16, further alternatives of the manufacturing method for the spring arm sleeve 1 are described. In a first step S 1, a planar element is first provided from which the tubular section 12 is later to be formed. This planar element may be made of metal, for example spring steel. According to a further embodiment, the planar element is made of plastic. Depending on the joining process to be supported by the spring arm sleeve 1, different material alternatives for manufacturing the spring arm sleeve 1 may thus be used.

(41) In step S2, corresponding to the chosen material alternative, several U-shaped apertures 22 regularly spaced apart from one another are provided in the planar element to form the spring arms 20 from these. According to process step S2A, it may be preferred to manufacture the apertures 22 by laser cutting. According to another embodiment, in step S2B the apertures 22 are etched. A further embodiment is that the apertures 22 in the planar element are manufactured by punching (step S2C).

(42) After the planar element has been provided with the apertures 22, in a subsequent step S3 the planar element is deformed into the tubular section 12 with passage channel 14. According to an embodiment of this method step, the deforming is carried out under the supply of heat (see step S3A). It may also be preferred to bring the planar element into the appropriate shape by bending (step S3B). Of course, this bending in step S3B can also be supported by the supply of heat.

(43) Based on the different embodiments of the spring arm sleeve 1 described above, it is understood that the tubular section 12 can comprise different cross-sectional contours after the deformation step. Thus, according to the different embodiments, it is intended to provide the deformed planar element, i.e. the tubular section 12, with a round or hexagonal or octagonal uniform cross-section.

(44) In a final step S4, the spring arms 20 are deformed radially inwards into the passage channel 14. This deformation may include the step of bending in the case of a metal planar element. In the same way, it is possible to bring the spring arms 20 into the appropriate configuration by using heat, especially if the planar element is made of plastic.