Patent ID: 8235950

Claim:
A safety needle comprising: a hollow needle having a tip for injecting into a patient, a needle hub that includes a catch and wherein the needle hub surrounds the hollow needle, a slidable sleeve that includes a projection and wherein the slidable sleeve is slidably mounted on the needle hub and slidable along the needle hub, and a pack surrounding the hollow needle, the needle hub and the slidable sleeve in a storage position and wherein the pack is releasably secured on at least one of the needle hub and the slidable sleeve by friction, the needle hub, the slidable sleeve and the pack each having a receiving end and an injection end distal to the receiving end, wherein the receiving end of the needle hub is configured to connect to and receive an injection device and the slidable sleeve is adapted to slide in the direction of the length of the needle between an extended position in which the needle tip is located inside the slidable sleeve and a retracted position in which the needle tip projects from the slidable sleeve, via an intermediate position between the extended position and the retracted position in which the slidable sleeve is releasably held in the intermediate position by engagement of the catch and projection, such that, in use, the slidable sleeve is moved into the intermediate position for injection into the patient by sliding along a tapering interior surface of the needle hub and then as the needle is inserted into the patient, the slidable sleeve is released from the intermediate position and caused to move into the retracted position, and in moving into the retracted position, a resultant force is generated, such that, on removal of the needle from the patient, the resultant force causes the slidable sleeve to move towards the injection end of the needle hub and into the extended position, the safety needle further comprising a locking mechanism capable of retaining the slidable sleeve in the extended position after removal of the needle from the patient, and wherein the pack covers at least the needle tip in the intermediate position, and by causing the pack to be moved in a direction towards the receiving end of the needle hub from the storage position to the intermediate position, the pack engages the slidable sleeve which is retracted from the extended position to the intermediate position, the pack being removable from the needle hub and slidable sleeve in the intermediate position.