Sliding sleeve and headrest arrangement

1. A sliding sleeve for fixing in a securing support, the sliding sleeve comprising a sleeve body with a coupling section with at least one flexible coupling face for bearing against the securing support, the flexible coupling face, in the coupling section, comprising a wall portion with a fully enclosed cavity formed within the wall portion, wherein the cavity is covered to an outside by a flexible bridge wall having an outwardly curved configuration in a non-installed state, and configured so that in an installed state the flexible bridge wall is pressed into the cavity and is changed into a stressed state.

2. A sliding sleeve according to claim 1 , wherein the cavity is of circumferential configuration.

3. A sliding sleeve according to claim 1 , wherein the cavity extends in a longitudinal direction of the sleeve body.

4. A sliding sleeve according to claim 3 , wherein a length of the cavity in the longitudinal direction is greater than a depth of the cavity in the wall portion.

5. A sliding sleeve according to claim 1 , wherein the at least one flexible coupling face comprises at least two flexible coupling faces configured to be at least one of arranged above and arranged next to one another in a longitudinal direction, wherein an outer surface of each of the coupling faces is beveled.

6. A headrest arrangement for a seat, the headrest arrangement comprising:

two headrest rods, which are spaced apart from one another in parallel;

a headrest body, which is fastened to the headrest rods;

two securing supports which are arrangeable and fixable in a frame of a backrest of the seat; and

sliding sleeves, each of the sliding sleeves being arranged in a respective one of the securing supports and each of the sliding sleeves comprising a sleeve body with a coupling section with at least one flexible coupling face for bearing against the securing support, the flexible coupling face, in the coupling section, comprising a wall portion with a fully enclosed cavity formed within the wall portion, wherein the cavity is covered to an outside by a flexible bridge wall having an outwardly curved configuration in a non-installed state, so that in an installed state the flexible bridge wall is pressed into the cavity and is changed into a stressed state.

7. A headrest arrangement according to claim 6 , wherein the cavity is of circumferential configuration.

8. A headrest arrangement according to claim 6 , wherein the cavity extends in a longitudinal direction of the sleeve body.

9. A headrest arrangement according to claim 8 , wherein a length of the cavity in the longitudinal direction is greater than a depth of the cavity in the wall portion.

10. A headrest arrangement according to claim 6 , wherein the at least one flexible coupling face comprises at least two flexible coupling faces configured to be at least one of arranged above and arranged next to one another in a longitudinal direction, wherein an outer surface of each of the coupling faces is beveled.

11. A headrest arrangement for a seat, the headrest arrangement comprising:

a headrest rod;

a headrest body fastened to said headrest rod;

a securing support configured to be mounted in the seat; and

a sliding sleeve arranged in said securing support, said sliding sleeve having a wall radially surrounding an interior space for receiving and radially securing said sliding sleeve to said headrest rod completely around said headrest rod, said sliding sleeve having a coupling section, said coupling section having a coupling face on a radial outside of said sliding sleeve, said coupling face being configured to bear against said securing support, a section of said wall being arranged directly radially inward of said coupling face, said section of said wall and said coupling face defining a hollow cavity radially between said section of said wall and said coupling face.

12. A sliding sleeve for fixing in a securing support, the sliding sleeve comprising a sleeve body with a coupling section with at least one flexible coupling face for bearing against the securing support, the flexible coupling face, in the coupling section, comprising a wall portion with a cavity, which is fully enclosed in a longitudinal direction and formed within the wall portion, wherein the cavity is covered to an outside by a flexible bridge wall having an outwardly curved configuration in a non-installed state, and configured so that in an installed state the flexible bridge wall is pressed into the cavity and is changed into a stressed state.

13. A sliding sleeve according to claim 12 , wherein the cavity is of circumferential configuration.

14. A sliding sleeve according to claim 12 , wherein the cavity extends in a longitudinal direction of the sleeve body.

15. A sliding sleeve according to claim 12 , wherein the at least one flexible coupling face comprises at least two flexible coupling faces configured to be at least one of arranged above and arranged next to one another in a longitudinal direction, wherein an outer surface of each of the coupling faces is beveled.