Device for injecting a liquid product having simplified assembly

1. A part of a liquid product injection device comprising:

an end sleeve,

a syringe support mobile relative to the end sleeve, the syringe support being intended to carry an injection syringe fitted with a removable protection cap, and

a deformable ring kinematically connected to the syringe support such that a movement of the syringe support is linked with a movement of the deformable ring, the deformable ring being mobile axially relative to the end sleeve and being elastically deformable between a configuration intended for the axial immobilization of the injection syringe in the syringe support during the injection and a configuration intended for the passage of the protection cap through the deformable ring;

wherein the deformable ring comprises at least one radial projection of control of the deformable ring, the radial projection of control configured to cooperate by contact with a complementary surface integral with the end sleeve according to the configuration intended for the axial immobilization of the injection syringe in the syringe support during the injection and the configuration intended for the passage of the protection cap through the deformable ring.

2. The part according to claim 1 , in which at least one sector of the deformable ring includes an axial abutment intended to cooperate with a distal shoulder of the injection syringe when the deformable ring is in the axial immobilization configuration, the deformable ring being deformed axially between its immobilization and passage configurations by radial movement of the sector carrying the axial abutment.

3. The part according to claim 2 , wherein the at least one radial projection of control of the deformable ring is carried by the sector carrying the axial abutment.

4. The part according to claim 3 , in which the deformable ring is urged elastically toward its immobilization configuration, the deformable ring being deformed against its elastic return force from its immobilization configuration to its passage configuration by centrifugal radial movement of the sector carrying the axial abutment.

5. The part according to claim 4 , in which the at least one radial projection of control of the deformable ring also forms a tenon for connection with the syringe support by being nested in a bracket of the syringe support forming a mortise.

6. The part according to claim 4 , in which the syringe support is movable relative to the end sleeve between:

a position for mounting the injection device in which the at least one radial projection of control of the deformable ring is radially aligned with a passage window formed in the end sleeve so as to allow the centrifugal radial movement of the sector carrying the axial abutment toward the passage configuration of the protection cap, and

an active position of the injection device in which the at least one radial projection of control of the deformable ring cooperates with the complementary surface integral with the end sleeve so as to prevent the centrifugal radial movement of the sector carrying the axial abutment toward the passage configuration of the protection cap.

7. The part according to claim 2 , in which the deformable ring is urged elastically toward its immobilization configuration, the deformable ring being deformed against its elastic return force from its immobilization configuration to its passage configuration by centrifugal radial movement of the sector carrying the axial abutment, and the sector carrying the axial abutment is provided with at least one axial slot facilitating the elastic deformation of the deformable ring against its elastic return force from its immobilization configuration to its passage configuration by centrifugal radial movement of the sector carrying the axial abutment.

8. The part according to claim 3 , in which the deformable ring is urged elastically toward its passage configuration, the deformable ring being deformed against its elastic return force from its passage configuration to its immobilization configuration by centripetal radial movement of the sector carrying the axial abutment.

9. The part according to claim 8 , in which the syringe support is movable relative to the end sleeve between:

a position awaiting the injection device in which the deformable ring is in its passage configuration, and

an active position of the injection device in which the deformable ring is in its configuration for the axial immobilization of the injection syringe in the syringe support, the at least one radial projection of control of the deformable ring cooperating, from the waiting position to the active position of the injection device, with the complementary surface of the end sleeve, the complementary surface forming a ramp causing the centripetal radial movement of the sector carrying the axial abutment toward the configuration for immobilization of the deformable ring.

10. The part according to claim 1 , in which the deformable ring is essentially made of polymer material.

11. An injection device comprising interconnected distal part and proximal part, wherein the distal part comprises the part as claimed in claim 1 .

12. The part according to claim 1 , in which two diametrically opposite sectors of the deformable ring each include an axial abutment intended to cooperate with a distal shoulder of the injection syringe when the deformable ring is in the axial immobilization configuration, the deformable ring being deformed axially between its immobilization and passage configurations by radial movement of the sector carrying the axial abutment.

13. The part according to claim 12 , in which the deformable ring comprises two diametrically opposite radial projections of control carried by the sector carrying the axial abutment, the two diametrically opposite radial projections of control being intended to cooperate with a complementary surface integral with the end sleeve according to the configuration to be imposed on the deformable ring.

14. The part according to claim 2 , in which the deformable ring is urged elastically toward its immobilization configuration, the deformable ring being deformed against its elastic return force from its immobilization configuration to its passage configuration by centrifugal radial movement of the sector carrying the axial abutment.

15. The part according to claim 2 , in which the deformable ring is urged elastically toward its passage configuration, the deformable ring being deformed against its elastic return force from its passage configuration to its immobilization configuration by centripetal radial movement of the sector carrying the axial abutment.