Patent ID: 6878137

Claim:
An injection device for injecting medical substances and designed to be implanted in a subcutaneous zone of the body of a patient in order to inject said substances into the body, the device ( 1 ) comprising: a hollow rigid housing ( 2 ) comprising a distal wall ( 6 ) from which there extend side walls ( 7 ) whose free ends ( 8 ) define a proximal opening ( 9 ); a membrane ( 3 ) which is situated on the free ends ( 8 ) of the side walls ( 7 ) to close the proximal opening ( 9 ) in substantially hermetic manner, thereby defining a chamber ( 12 ); a duct ( 4 ) connected to the rigid body ( 2 ) and connecting the chamber ( 12 ) to the outside of the injection device ( 1 ); the membrane ( 3 ) being designed during injection to be pierced by a needle for delivering a dose of said substance into the body of the patient via the chamber ( 12 ) and the duct ( 4 ); the side walls ( 7 ) and the distal wall ( 6 ) of the rigid body ( 2 ) being non-pierceable by the needle so as to prevent the needle penetrating into the body of the patient while it is being inserted into the chamber ( 12 ); and a casing ( 15 ) of elastomer material covering the housing ( 2 ), the membrane ( 3 ) forming an integral portion of the casing ( 15 ), and the grade of elastomer used for the membrane ( 3 ) is being different from that used for the casing ( 15 ).