Adjustment assembly of respiratory mask

1. An adjustment assembly of a respiratory mask, comprising:

a forehead fixing device, adapted to fix the respiratory mask on a user's forehead; and

an adjustment device, adapted to adjust a position of the forehead fixing device relative to the user's forehead, comprising a base body, multiple connectors set on the base body and multiple connector matching pieces respectively set on the multiple connectors, each of the multiple connectors is connectable to the forehead fixing device, and the connectors are located on an outer circle of the base body with a same interval in a circumferential direction of the base body, a through hole passing through the center of the base body to connect with one end of an airway tube; and

wherein when the respiratory mask is worn, only one connector selected from the multiple connectors is connected to the forehead fixing device, wherein each of the multiple connector matching pieces forms an angle with a longitudinal axis of the through hole and each of the angles between each of the multiple matching pieces and the longitudinal axis of the through hole are different from each other.

2. The adjustment assembly of claim 1 , wherein, the connection between each of the connectors and the forehead fixing device is detachable.

3. The adjustment assembly of claim 2 , further comprising a forehead fixing matching piece set on the forehead fixing device.

4. The adjustment assembly of claim 3 , wherein, each of the connector matching pieces and the forehead fixing matching piece respectively are a plug and a groove used for plugging, or a nut and a bolt used for screwing, or a hole and a protruding piece used for snapping.

5. The adjustment assembly of claim 3 , wherein, a bandage connector is set on each connector, adapted to be connected with a bandage device.

6. The adjustment assembly of claim 3 , wherein, angles between the connector matching pieces and the longitudinal axis are adjustable;

wherein, the longitudinal axis extends horizontally from a center of the base body, to the user.

7. The adjustment assembly of claim 6 , wherein, the adjustment device comprises three connectors and three connector matching pieces respectively set on the three connectors, the angles between the connector matching pieces and the longitudinal axis are represented as a first angle, a second angle, and a third angle respectively;

wherein, the differences between the first angle and the second angle and between the first angle and the third angle are adjusted to be less than or equal to 90° and more than 0°, or less than or equal to 60° and more than 0°, or less than or equal to 30° and more than 5°.

8. The adjustment assembly of claim 3 , wherein, distances between bottoms of the connector matching pieces and a vertical plane that through a center of the base body are adjustable.

9. The adjustment assembly of claim 8 , wherein, the adjustment device comprises three connectors and three connector matching pieces respectively set on the three connectors, the distances between the bottoms of the connector matching pieces and the vertical plane are represented as a first distance, a second distance, a third distance respectively;

the differences between the first distance and the second distance and between the first distance and the third distance are adjusted to be less than or equal to 50 mm and more than 0 mm, or less than or equal to 35 mm and more than 0 mm, or less than or equal to 25 mm and more than 5 mm.

10. The adjustment assembly of claim 1 , wherein, the lumber of the connectors is three.

11. The adjustment assembly of claim 1 , wherein, the forehead fixing device comprises a forehead padding part and a fixing part; one connecting end of the fixing part connects with the forehead padding part, and another connecting end connects with the one connector.

12. The adjustment assembly of claim 11 , wherein, the fixing part is ergonomically streamlined which is curved to fit to the user's face.

13. The adjustment assembly of claim 11 , wherein, the forehead padding part comprises a forehead pad, adapted to contact a user's forehead.

14. The adjustment assembly of claim 1 , wherein, the through hole is connected via a connecting hole of a mask assembly with a chamber of the mask assembly configured to accommodate a user's nose or snout.

15. The adjustment assembly of claim 14 , wherein, the adjustment device rotatably connects with the mask assembly via the connection hole.

16. The adjustment assembly of claim 1 , wherein, the base body and connectors are integrated.

17. The respiratory mask of claim 1 , wherein, the adjustment device connects rotatable with a mask assembly of the respiratory mask.