Locking device for a roller blind

1. Locking device for a pre-tensioning arrangement of a roller blind or a Venetian blind, comprising a sleeve and a plug element adapted to be inserted into the sleeve, a locking member and a pin, wherein

the sleeve on its inner circumferential surface comprises at least one recess;

the plug element comprises a wall having a longitudinal extension and a circumferential extension, and the wall defining a cavity adapted to receive the pin, and wherein the wall comprises a through-going opening, the through-going opening being adapted to receive the locking member;

the pin comprises a longitudinal extension, and a locking portion and a releasing portion along the pin longitudinal extension, and wherein the pin is movable inside the cavity and along the longitudinal extension of the plug element between a locking position and a releasing position;

in which locking position the locking portion of the pin longitudinally coincides with the through-going opening of the wall, whereby the locking member will engage the locking portion and be urged by the locking portion radially outwardly into the recess of the sleeve thereby preventing the plug element from being rotated in view of the sleeve, and

in which releasing position the releasing portion of the pin longitudinally coincides with the through-going opening of the wall, whereby the locking member will engage the releasing portion of the pin and be allowed to move radially inwardly out of the recess of the sleeve, thereby allowing the plug element to be rotated in view of the sleeve.

2. Locking device according to claim 1 , wherein the cavity as seen in the longitudinal direction of the wall comprises a first abutment and a second abutment, and wherein the pin is biased towards the second abutment by a spring acting between the first abutment and the pin, and wherein the second abutment comprises at least one opening allowing the pin to be operated by an actuator to thereby be moved from the locking position to the releasing position.

3. Locking device according to claim 1 , wherein the locking device further comprises a pre-tensioning spring having a first and a second end, the first end being connected to the plug element and the second end being connected to the sleeve.

4. Locking device according to claim 1 , wherein the plug element extends through and past the sleeve, and wherein the plug element as seen in a position past the sleeve comprises a connector, and wherein the locking device further comprises a pre-tensioning spring having a first and a second end, the first end being connected to the connector and the second end being connected to the sleeve.

5. Locking device according to claim 3 , wherein the plug element as seen along its longitudinal extension is connected to a shaft, wherein the plug element and the shaft are interconnected by a driver.

6. Locking device according to claim 1 , wherein the locking member is a ball or a peg.

7. Locking device according to claim 1 , wherein a plurality of recesses are arranged side by side in the circumferential direction on the inner circumferential surface of the sleeve.

8. Locking device according to claim 1 , wherein the sleeve along its outer circumferential surface comprises at least one longitudinal projection adapted to engage at least one recess on the inner wall of a tube supporting the blind of a roller blind or a Venetian blind.

9. Locking device according to claim 1 , wherein the at least one recess of the sleeve has an arc shaped or V-shaped cross section as seen in the radial direction of the sleeve.

10. A roller blind or a Venetian blind comprising a tube supporting a blind, wherein the tube comprises a locking device according to claim 1 .