FOLDABLE CHAIR

Abstract

The invention relates to a portable chair (1) having two front chair legs (2, 3), two rear chair legs (4, 5), two front chair arms (6, 7), two rear chair arms (8, 9), and two connection elements which are connected via a connection rod. The front chair legs and the rear chair legs each have a free end (2a, 3a, 4a, 5a) which is oriented towards an underlying surface (10), and the front chair arms and rear chair arms each have a free end (8c, 9c) which is oriented towards a seat surface (11) that is defined or can be defined by free ends (6a, 7a) of the front chair arms and free ends of the rear chair arms (8, 9).

Claims

1. A portable chair comprising two front chair legs and two rear chair legs, as well as two front chair arms and two rear chair arms, wherein the front chair legs and the rear chair legs each have a free end which is oriented toward a substrate, and wherein the front chair arms and rear chair arms in each case have a free end (8c, 9c) which is oriented toward a seat surface, wherein the seat surface is able to be spanned or is spanned over free ends of the front chair arms and free ends of the rear chair arms, wherein the front chair legs and the front chair arms are fastened to and/or in a first, front connection element, and wherein the rear chair legs and the rear chair arms are fastened to and/or in a second, rear connection element, wherein the first, front connection element is connected via at least one first connection rod to the second, rear connection element.

2. The chair as claimed in claim 1, wherein the first, front connection element is connected via at least two connection rods to the second, rear connection element, wherein preferably a second connection rod is arranged parallel to and above the first connection rod.

3. The chair as claimed in claim 1, wherein the front chair legs and the rear chair legs as well as the front chair arms and the rear chair arms each are designed as a tubular portion and wherein the two front chair legs are connected together via a first resilient cord, wherein the two rear chair legs are connected together via a second resilient cord, wherein the two front chair arms are connected together via a third resilient cord and wherein the two rear chair arms are connected together via a fourth resilient cord.

4. The chair as claimed in claim 1, wherein the resilient cord, which in each case connects together the two front chair legs or the two front chair arms or the two rear chair legs or the two rear chair arms, is guided through the respective tubular portion of the respective two chair legs or chair arms connected together, and is guided through the respective front or rear connection element between the respective tubular portions connected together, and deflected there.

5. The chair as claimed in claim 3, wherein in each case two resilient cords are guided and deflected in the front connection element and in the rear connection element, wherein preferably the first resilient cord and the third resilient cord are guided in the front connection element and the second resilient cord and the fourth resilient cord are guided in the rear connection element.

6. The chair as claimed in claim 1, wherein the front chair legs are arranged at a first acute angle to one another and wherein the rear chair legs are arranged at a second acute angle to one another, wherein preferably the first acute angle between the front chair legs and preferably also the second acute angle between the rear chair legs is 50-80 degrees, in particular preferably 60-70 degrees, and wherein the front chair arms are preferably also arranged at a third acute angle to one another which, however, is larger than the first acute angle defined between the front chair legs, and preferably is 80-85 degrees, and wherein preferably the rear chair arms are arranged at a fourth acute angle to one another, wherein this fourth acute angle between the rear chair arms is preferably smaller than the third acute angle defined between the front chair arms, wherein this fourth acute angle between the rear chair arms is preferably 45-50 degrees.

7. The chair as claimed in claim 2, wherein the first front connection element and the second rear connection element each have two respective lower tubular sleeves for receiving two chair legs and two upper tubular sleeves for receiving two chair arms and wherein the first front connection element and the second rear connection element have two respective central tubular sleeves extending from a first side to a second side of the connection element and arranged on top of one another for receiving the first, lower connection rod and the second, upper connection rod.

8. The chair as claimed in claim 1, wherein the connection element is configured in one piece.

9. The chair as claimed in claim 7, wherein the first opening of the respective lower tubular sleeve which is downwardly oriented toward the substrate and which is suitable for receiving a chair leg is larger than the upwardly oriented second opening of the respective lower tubular sleeve and wherein the second opening of the respective upper tubular sleeve which is upwardly oriented toward the seat surface and which is suitable for receiving a chair arm is larger than the first, downwardly oriented opening of the respective upper tubular sleeve and wherein the second, upper opening of the respective lower tubular sleeve and the first, lower opening of the respective upper tubular sleeve are suitable for passing through it a resilient cord which in each case connects together two chair legs or two chair arms.

10. The chair as claimed in claim 7, wherein the upper tubular sleeves for the chair arms are connected together at their lower end by a first lower reinforcing rib and at their upper end by a second upper reinforcing, wherein the lower tubular sleeves for the chair legs are preferably integrally formed on at least one of these reinforcing ribs.

11. The chair as claimed in claim 1, wherein the rear chair arms are longer than the front chair arms, wherein the rear chair arms are preferably made up of at least two tubular portions which are able to be telescoped and/or inserted into one another and which are preferably connected together via an adapter element, wherein the adapter element is preferably received in a lower region by a first, lower tubular portion of the rear chair arm and is received in an upper region by an upper tubular portion of the rear chair arm, wherein the adapter element preferably has an axial through-opening which is suitable for receiving a resilient cord.

12. The chair as claimed in claim 1, wherein the chair legs at their free end facing the substrate have a terminal stop, a free end of a resilient cord preferably being able to be fastened thereon and/or therein, wherein the terminal stop is preferably fastened at its end facing the substrate in and/or on a foot.

13. The chair as claimed in claim 1, wherein the chair has at least one fastening region with a complementary closure means, in particular a Velcro strip, which is suitable for fastening accessories to the chair, preferably by means of a hook strip, in particular a hook-loop closure.

14. The chair as claimed in claim 1, wherein the seat surface is configured from woven fabric, which is coated or uncoated on one side or on both sides and which is produced from natural fibers and/or plastics fibers, wherein the woven fabric preferably has different mesh sizes in some areas, wherein at least one region of the seat surface is in particular preferably configured from air-permeable mesh-woven fabric.

15. The chair as claimed in claim 1, wherein the chair is a foldable chair, wherein in a folded-up state the chair arms and chair legs extend along the connection rods which are fastened fixedly to and/or in the connection elements or are able to be releasably fastened to and/or in the connection elements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Preferred embodiments of the invention are disclosed hereinafter with reference to the drawings, which merely serve for explanation and are not to be interpreted as limiting. In the drawings:

[0021] FIG. 1 shows a perspective view of a portable chair or foldable chair, respectively, according to a first preferred embodiment of the present invention;

[0022] FIG. 2 shows a schematic view from above of the chair frame of FIG. 1 (chair without seat surface);

[0023] FIG. 3 shows a schematic view from the front (from the entry side, in the viewing direction V of FIG. 4) of the chair frame of FIG. 1;

[0024] FIG. 4 shows a schematic view from the left (in the viewing direction X of FIG. 3) of the chair frame of FIG. 3;

[0025] FIG. 5 shows an exploded view of the chair frame of FIG. 3;

[0026] FIG. 6 shows different schematic views of the front connection element of the chair of FIG. 1, including in FIG. 6a) from below (from the substrate), in FIG. 6b) from above (from the seat surface), in FIG. 6c) from the front, in FIG. 6d) from the rear (from the backrest side in the viewing direction Z of FIG. 4), in FIG. 6e) from the left, in FIG. 6f) from the right (in the viewing direction Y of FIG. 3) in a perspective view;

[0027] FIG. 7 shows different views of the rear connection element of the chair of FIG. 1, including in FIG. 7a) from below, in FIG. 7b) from above, in FIG. 7c) from the front, in FIG. 7d) from the rear, in FIG. 7e) from the left, in FIG. 7f) from the right in a perspective view;

[0028] FIG. 8 shows in a) a schematic view of an adapter element of the chair of FIG. 1; in b) a sectional view through the line A-A of FIG. 8a); in c) a schematic view of the adapter element of FIG. 8a) from above; in d) a perspective view of the adapter element of FIG. 8a;

[0029] FIG. 9 shows in 9a) a schematic view of a terminal stop of the chair of FIG. 1 from the front; in 9b) a schematic view of the terminal stop of FIG. 9a) from the side; in 9c) a sectional view through the line B-B of FIG. 9a); in 9d) a schematic view of the terminal stop of FIG. 9a) from above; in 9e) a perspective view of the terminal stop of FIG. 9a);

[0030] FIG. 10 shows in 10a) a schematic view of a foot of the chair of FIG. 1; in 10b) a sectional view through the line C-C of FIG. 10a); in FIG. 10c) a schematic view of the foot of FIG. 10a) from below; in FIG. 10d) a perspective view of the foot of FIG. 10a);

[0031] FIG. 11 shows a schematic view of the chair frame of FIG. 1 in the folded-up state.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0032] A foldable chair according to a first preferred embodiment of the present invention is shown in FIG. 1. Said foldable chair has two front chair legs 2, 3 and two rear chair legs 4, 5, as well as two front chair arms 6, 7 and two rear chair arms 8, 9. The chair legs 2, 3, 4, 5 have in each case a free end 2a, 3a, 4a, 5a facing downwardly or facing the substrate 10 or the ground, respectively, in each case a foot, which for example may be configured as a ferrule, being fastened thereto. The chair arms 6, 7, 8, 9 in each case have a free end 6a, 7a, 8c, 9c facing away from the substrate 10 or upwardly, respectively. A seat surface 11 is spanned over these free ends 6a, 7a, 8c, 9c, said seat surface preferably providing the user with a seat support and a seat backrest. As shown in the present exemplary embodiment, a seat backrest is permitted by the rear chair arms 8, 9 being configured to be longer than the front chair arms 6, 7. In the exemplary embodiment shown in FIG. 1 this is implemented by the rear chair arms 8, 9 being configured in multiple parts, wherein two rod portions or tubular portions are axially inserted inside one another. In the present exemplary embodiment, the seat surface 11 is formed from a woven textile material. The seat surface is preferably formed from a combination of individual portions of different types of material which may consist of natural fibers or plastics fibers and which may also have different functions (for example air-permeability) or patterns. The textile cloth in this case is slipped over the free ends 6a, 7a, 8c, 9c of the chair arms 6, 7, 8, 9 by means of small pockets fastened thereto on the corners thereof on the lower face. The front chair legs 2, 3 and the front chair arms 6, 7 are fastened to a front connection element 12 and the rear chair legs 4, 5 and the rear chair arms 8, 9 are fastened to a rear connection element 13. In the preferred exemplary embodiment shown in FIG. 1, the two connection elements 12, 13 are connected together via two connection rods 14, 15 arranged above one another and parallel to one another, along their respective longitudinal axis L14 or L15, respectively.

[0033] In this case each connection element 12, 13 has six tubular sleeves 26-37 which are fastened thereto and which serve for receiving the respective chair legs 2, 3 or 4, 5, or chair arms 6, 7 or 8, 9 and connection rods 14, 15, respectively. The front connection element 12 has a left-hand lower tubular sleeve 26 for receiving the left-hand front chair leg 2, as well as a right-hand lower tubular sleeve 27 for receiving the right-hand front chair leg 3. Similarly, the front connection element 12 has a left-hand upper tubular sleeve 28 for receiving the left-hand front chair arm 6 as well as a right-hand upper tubular sleeve 29 for receiving the right-hand front chair arm 7. The four tubular sleeves 26, 27, 28, 29 for receiving the front chair legs 2, 3 and the front chair arms 6, 7 are substantially connected together via a plate 20 which at the same time serves as a reinforcing rib 38, 39 between the respective two lower tubular sleeves 26, 27 or the respective upper tubular sleeves 28, 29, respectively.

[0034] The rear connection element 13 has a left-hand lower tubular sleeve 30 for receiving the left-hand rear chair leg 4 as well as a right-hand lower tubular sleeve 31 for receiving the right-hand rear chair leg 5. Similarly, the rear connection element 13 has a left-hand upper tubular sleeve 32 for receiving the left-hand rear chair arm 8 as well as a right-hand upper tubular sleeve 33 for receiving the right-hand rear chair arm 9. The four tubular sleeves 30, 31, 32, 33 for receiving the rear chair legs 4, 5 and the rear chair arms 8, 9 are substantially connected together via a plate 21, which at the same time serves as a reinforcing rib 38, 39 between the two respective lower tubular sleeves 30, 31 or the respective upper tubular sleeves 32, 33, respectively.

[0035] In this case, the left-hand lower tubular sleeve 26 and the right-hand lower tubular sleeve 27 are oriented on a front side 22 of the plate 20 or of the front connection element 12, respectively, toward the front and the left-hand upper tubular sleeve 28 and the right-hand upper tubular sleeve 29 are oriented on a rear side 23 of the plate 20 or of the front connection element 12, respectively, toward the rear. In contrast, the left-hand lower tubular sleeve 30 and the right-hand lower tubular sleeve 31 on a rear side 25 of the plate 21 or of the rear connection element 13, respectively, are oriented toward the rear and the left-hand upper tubular sleeve 32 and the right-hand upper tubular sleeve 33 on a front side 24 of the plate 21 or of the rear connection element 13, respectively, are oriented toward the front. As may be seen in FIG. 2 in the view from above, this has the result that in the exemplary embodiment shown the articulation of the chair legs 2, 3, 4, 5 on the chair 1 is arranged further to the outside in the peripheral direction U of the chair than the articulation of the chair arms 6, 7, 8, 9.

[0036] Additionally, each connection element 12, 13 has two central tubular sleeves 34, 35 or 36, 37, respectively, arranged above one another and parallel to one another for receiving one respective end of a connection rod 14, 15 which connects the front connection element 12 to the rear connection element 13. These central tubular sleeves 34, 35 or 36, 37, respectively, are arranged transversely to the direction of extension of the plate 20, 21 or to the plane of the plate 20, 21 of the respective connection element 12, 13, respectively, or pass through the plate 20, 21 to a certain extent, respectively. On the front face 22 of the front connection element 12 and on the rear face 25 of the rear connection element 13 the central tubular sleeves 34, 35 or 36, 37, respectively, are closed in the exemplary embodiment shown. The two connection rods 14, 15 extend along their longitudinal axes L14, L15 from the front to the rear and are arranged above one another, spaced apart from one another, forming an intermediate space 48.

[0037] The front chair legs 2, 3 and rear chair legs 4, 5 are arranged in each case at an acute angle α1 (first acute angle), β1 (third acute angle) to one another, which in the present exemplary embodiment is about 60-70 degrees. The front chair arms 6, 7 are also arranged at an acute angle α2 (second acute angle) to one another which is larger than the angle α1 spanned between the front chair legs 2, 3 and in the present exemplary embodiment of FIG. 3 is 80-85 degrees. The rear chair arms 8, 9 which in the present exemplary embodiment of FIG. 3 substantially span the seat backrest, are arranged at an acute angle β2 (fourth acute angle) to one another, wherein this angle β2 is smaller than the angle α2 spanned between the front chair arms 6, 7 in the present exemplary embodiment, and in the exemplary embodiment of FIG. 3 is 45-50 degrees.

[0038] In the exploded view of FIG. 5 it may be seen that in each case two chair legs 2, 3 or 4, 5, respectively, and in each case two chair arms 6, 7 or 8, 9, respectively, are connected together in each case by a resilient cord. The chair 1 has four such resilient cords in the exemplary embodiment shown of FIG. 5. In this case, each resilient cord 16, 17, 18, 19, which is guided through a chair leg 2, 3, 4, 5 or a chair arm 6, 7, 8, 9, is deflected in the connection element 12, 13 in order to enter at this point the chair leg 2, 3, 4, being adjacent with respect to the peripheral direction U of the chair 1, or the chair arm 6, 7, 8, 9, respectively, being adjacent with respect to the the peripheral direction U of the chair 1, which is articulated to the same connection element 12, 13. Each resilient cord 16, 17, 18, 19 in this case has two ends 16a, 16b, 17a, 17b, 18a, 18b, 19a, 19b. Each of these ends is anchored in a terminal stop 42, as illustrated in FIG. 5. The terminal stop 42 in this case has a cylindrical portion 42a which has a hollow space and/or a recess 43 and is provided on its side facing the periphery with a base which has a peripheral flange 42 which bears against the end of the respective chair leg or chair arm and closes the tubular portion of the respective chair leg or chair arm. The resilient cord 16, 17, 18, 19 has at its two ends 16a, 16b, 17a, 17b, 18a, 18b, 19a, 19b, for example, a knot which during assembly is inserted into the recess 43 of the terminal stop 42, as shown in FIG. 9, and comes to bear in a tapered portion of the recess 43, wherein the resilient cord is able to enter through the tapered recess into the respective tubular portion.

[0039] The terminal stop 42 on the chair arms 6, 7, 8, 9 forms the terminal portion or the upper end respectively, of the chair arm 6, 7, 8, 9. Additionally a foot 44 is mounted on the chair legs 2, 3, 4, 5 via the end of the respective chair leg 2, 3, 4, 5 closed by the terminal stop 42. In this case the end of the chair leg 2, 3, 4, is received in a blind hole 47 of the foot and fastened therein, for example fixedly bonded or press-fitted thereon. The foot 44 shown in FIG. 10 also has a tip 46 for supporting the chair 1 on the substrate 10. The foot 44 also has a ring consisting of a plurality of radial fins 45 which extend radially outwardly at regular intervals from one another and enlarge the bearing surface of the foot 44 with the substrate 10. This is particularly useful in soft substrates, such as for example on forest soil, where the tip 46 sinks into the ground. The shape and design of the feet may be constructed to be variable and to be replaceable according to the type of ground.

[0040] In the exemplary embodiment shown, the rear chair arms 8, 9 are in each case configured from two tubular portions 8a, 8b or 9a, 9b, respectively, as described above and shown particularly clearly in the exploded view of FIG. 5. Said tubular portions are connected together in each case by an adapter element 41, which in each case has an upper portion 41b and a lower portion 41a. The upper portion 41b of the adapter element 41 in this case is inserted into the upper tubular portion 8b, 9b, whilst the lower portion 41a is inserted into the lower tubular portion 8a, 9a of the respective rear chair arm 8, 9. The diameter of the upper portion 41b is larger than the diameter of the lower portion 41a, so that the lower tubular portion 8a, 9a with its upper end comes to bear against the shoulder 41d, toward the upper portion 41b of the adapter element 41.

[0041] In the exemplary embodiment shown in FIGS. 5 and 8, the lower portion 41a has a ribbed region 41c or a ribbing, respectively, for improving the grip in the case of fastening by adhesive bonding in the lower tubular portion 8a, 9a. The upper end and the lower end of the adapter element 41 are configured to extend slightly conically. So that the resilient cord 19 may be guided through the respective adapter element 41, the adapter element has an axial through-opening and/or through-bore 49 which has only a slightly larger diameter than the diameter of the resilient cord 19. The front connection element 12 is shown in more detail in FIG. 6 and the rear connection element 13 is shown in more detail in FIG. 7.

[0042] Each connection element 12, 13 forms in a manner of speaking a tuberous element with six tubular sleeves 26, 27, 28, 29, 34, 35 or 30, 31, 32, 33, 36, 37, respectively. In this case, the upper tubular sleeves 28, 29, 32, 33 for the chair arms 6, 7, 8, 9 at their lower end are connected together by a first or lower reinforcing rib 38, respectively, and at their upper end by a second or upper reinforcing rib 39, respectively. The lower tubular sleeves 26, 27, 30, 31 for the chair legs 2, 3, 4, 5 are then so to speak integrally formed on these reinforcing ribs 38, 39. The tubular sleeves 26, 27, 30, 31 for the chair legs 2, 3, 4, 5 pass through the respective upper reinforcing rib 39. As a result, the upper end of the respective tubular sleeve 26, 27, 30, 31 comes to bear against the opposing side of the respective upper reinforcing rib 39 compared to the lower end of the respective tubular sleeve 26, 27, 30, 31. Thus, the upper openings 26b, 27b of the front chair leg tubular sleeves 26, 27 are arranged on the rear face 23 of the front connection element 12, and the lower openings 26a, 27a are arranged on the front face 22 of the front connection element 12. The upper openings 30b, 31b of the rear chair leg tubular sleeves 30, 31 are correspondingly arranged on the front face 24 of the rear connection element 13 and the lower openings 30a, 31a on the rear face 25. In other words, on a left-hand side and on a right-hand side of the front and the rear connection elements 12, 13 in each case an upper tubular sleeve 28, 29, 32, 33 intersects with a lower tubular sleeve 26, 27, 30, 31.

[0043] The connection element 12, 13 has the approximate appearance of being formed from a plate 20, 21 (which forms the reinforcing ribs), six tubular sleeves being integrally formed thereon, wherein the plate substantially extends in a direction transversely to the direction of extension L14, L15 of the connection rods 14, 15 in the plane spanned by the respective chair arms 6, 7, 8, 9 at the angle α2 or β2, respectively. The plate 20, 21 in this case has substantially the shape of a circular sector.

[0044] The reinforcing rib 40, which is configured so to speak as a web between the two central tubular sleeves 34, 35, is visible in FIG. 6d, said reinforcing rib extending on the rear face 23 of the first front connection element 12 substantially transversely to the longitudinal axis of the connection rods 14, 15. Similarly, in FIG. 7c the reinforcing rib 40 extends between the two central tubular sleeves 34, 35 on the front face 24 of the second rear connection element 13 substantially transversely to the longitudinal axis L14, L15 of the connection rods 14, 15.

[0045] The type of path of the resilient cord 17 is explained hereinafter by way of example with reference to the two rear chair legs 4, 5 but expediently also applies to the type of path for the other three resilient cords 16, 18, 19 (with the exception that the resilient cord 19 is longer than the others and extends through two respective tubular portions 8a, 8b and/or 9a, 9b of the rear chair arms 8, 9 and therebetween through an adapter element).

[0046] As is visible in the exploded view of FIG. 5, the resilient cord 17 extends from the anchoring thereof with its first end 17a in the terminal stop 42 of the left-hand rear chair leg 4 through the tubular portion of the rear chair leg. The rear chair leg 4 on the rear connection element 13 enters into the lower opening 30a of the left-hand lower tubular sleeve 30 (shown in detail in FIG. 7) and the resilient cord 17 passes through the upper opening 30b out of the rear connection element 13, where its direction is deflected, and passes through the upper opening 31b of the right-hand lower tubular sleeve 31 into the tubular portion of the right-hand rear chair leg 5. The resilient cord 17 then extends through the right-hand rear chair leg 5 until at its second end 17b it is anchored again in a terminal stop 42 of the right-hand rear chair leg 5.

[0047] In FIG. 11 a chair 1 according to the invention is shown in the folded-up state. When folding up the chair 1 the two connection rods 14, 15 remain connected to the respective connection element 12, 13 and the respective two chair legs 2,3/4,5 and chair arms 6,7/8,9 are pulled out of the respective tubular sleeve 26,27/28,29/30,31/32,33 and placed parallel to the longitudinal axis L14, L15 of the connection rods 14, 15. When placed together, the upper tubular portions 8b, 9b and lower tubular portions 8a, 9a of the chair arms 8, 9 are additionally separated from one another in that the respective upper tubular portion 8b, 9b of the chair arms 8, 9 is separated from the respective adapter element 41. In this case the respective lower tubular portion 8a, 9a and the lower region 41a of the adapter element remain in the lower tubular portion 8a, 9a.

LIST OF REFERENCE NUMERALS

[0048] 1 Foldable chair

[0049] 2 Left-hand front chair leg

[0050] 2a Free end of 2

[0051] 3 Right-hand front chair leg

[0052] 3a Free end of 3

[0053] 4 Left-hand rear chair leg

[0054] 4a Free end of 4

[0055] 5 Right-hand rear chair leg

[0056] 5a Free end of 5

[0057] 6 Left-hand front chair arm

[0058] 6a Free end of 6

[0059] 7 Right-hand front chair arm

[0060] 7a Free end of 7

[0061] 8 Left-hand rear chair arm

[0062] 8a First, lower tubular portion of 8

[0063] 8b Second, upper tubular portion of 8

[0064] 8c Free end of 8

[0065] 9 Right-hand rear chair arm

[0066] 9a First, lower tubular portion of 9

[0067] 9b Second, upper tubular portion of 9

[0068] 9c Free end of 9

[0069] 10 Substrate

[0070] 11 Seat surface

[0071] 12 First, front connection element

[0072] 13 Second, rear connection element

[0073] 14 First, lower connection rod

[0074] 15 Second, upper connection rod

[0075] 16 First resilient cord

[0076] 16a First end of 16

[0077] 16b Second end of 16

[0078] 17 Second resilient cord

[0079] 17a First end of 17

[0080] 17b Second end of 17

[0081] 18 Third resilient cord

[0082] 18a First end of 18

[0083] 18b Second end of 18

[0084] 19 Fourth resilient cord

[0085] 19a First end of 19

[0086] 19b Second end of 19

[0087] 20 Plate of 12

[0088] 21 Plate of 13

[0089] 22 First, front side of 12

[0090] 23 Second, rear side of 12

[0091] 24 First, front side of 13

[0092] 25 Second, rear side of 13

[0093] 26 Left-hand lower tubular sleeve of 12

[0094] 26a First lower opening of 26

[0095] 26b Second upper opening of 26

[0096] 27 Right-hand lower tubular sleeve of 12

[0097] 27a First, lower opening of 27

[0098] 27b Second, upper opening of 27

[0099] 28 Left-hand upper tubular sleeve of 12

[0100] 28a First, lower opening of 28

[0101] 28b Second, upper opening of 28

[0102] 29 Right-hand upper tubular sleeve of 12

[0103] 29a First, lower opening of 29

[0104] 29b Second, upper opening of 29

[0105] 30 Left-hand lower tubular sleeve of 13

[0106] 30a First, lower opening of 30

[0107] 30b Second, upper opening of 30

[0108] 31 Right-hand lower tubular sleeve of 13

[0109] 31a First lower opening of 31

[0110] 31b Second upper opening of 31

[0111] 32 Left-hand upper tubular sleeve of 13

[0112] 32a First, lower opening of 32

[0113] 32b Second, upper opening of 32

[0114] 33 Right-hand upper tubular sleeve of 13

[0115] 33a First, lower opening of 33

[0116] 33b Second, upper opening of 33

[0117] 34 Lower central tubular sleeve of 12 for 14

[0118] 35 Upper central tubular sleeve of 12 for 15

[0119] 36 Lower central tubular sleeve of 13 for 14

[0120] 37 Upper central tubular sleeve of 13 for 15

[0121] 38 Lower reinforcing rib

[0122] 39 Upper reinforcing rib

[0123] 40 Central reinforcing rib

[0124] 41 Adapter element

[0125] 41a Lower region of 41

[0126] 41b Upper region of 41

[0127] 41c Ribbed region of 41a

[0128] 41d Shoulder between 41a, 41b

[0129] 42 Terminal stop

[0130] 42a Cylindrical region of 42

[0131] 42b Peripheral flange of 42

[0132] 43 Recess in 42

[0133] 44 Foot

[0134] 45 Fin of 44

[0135] 46 Tip of 44

[0136] 47 Blind hole in 44

[0137] 48 Intermediate space between 14, 15

[0138] 49 Axial through-opening of 41

[0139] α1 First acute angle between 2, 3

[0140] α2 Second acute angle between 6, 7

[0141] β1 Third acute angle between 4, 5

[0142] β2 Fourth acute angle between 8, 9

[0143] L2 Longitudinal axis of 2, 26

[0144] L3 Longitudinal axis of 3, 27

[0145] L4 Longitudinal axis of 4, 30

[0146] L5 Longitudinal axis of 5, 31

[0147] L6 Longitudinal axis of 6, 28

[0148] L7 Longitudinal axis of 7, 29

[0149] L8 Longitudinal axis of 8, 32

[0150] L9 Longitudinal axis of 9, 33

[0151] L14 Longitudinal axis of 14

[0152] L15 Longitudinal axis of 15

[0153] U Peripheral direction of 1

[0154] U Peripheral direction of 1

[0155] V Viewing direction from the front

[0156] X Viewing direction from the left

[0157] Y Viewing direction from the right

[0158] Z Viewing direction from the rear