Patent EA-002259-B1 (EA)
Title: Safety syringe
Inventor: MALENCHEK ROBERT
IPC: A61M5/32
Filed: 1998-12-17
Abstract: 1. A safety syringe device (2) comprising: a housing (4) having a bore (23) extending in an axial direction (92) from a proximal housing end (26) to a distal end (28); a vial (8) having a fluid receiving chamber (86) for receiving a plunger (6) and having proximal (88) and distal ends, said vial for axial displacement in the housing bore between retracted and extended positions, the distal vial end for securing a needle (36) thereto in fluid communication with the vial chamber, said needle being fully retracted in the bore when the vial is retracted and extending from the bore distal end when the vial is extended; resilient means (12) for resiliently urging the vial to the retracted position; characterized in that: positioning means (10, 42, 44, 46, 60, 62, 66, 100) are included responsive to an initial vial axial displacement for releasably locking the vial in the extended position, said positioning means for unlocking the vial upon a subsequent vial axial displacement and for displacing the vial to a second retracted position in response to said unlocking. 2. The device of claims 1 characterized in that the positioning means comprises ratchet means (10, 42, 44, 46, 60, 62, 66, 100) coupled to the vial (8) and housing bore (23) for said releasably locking, for said unlocking the vial and for said displacing to the second retracted position. 3. The device of claim 2, characterized in that the ratchet means comprises ratchet teeth (76, 82) fixed to the housing (4) in the bore and ratchet teeth (112, 112') fixed externally to the vial and a pawl (122) with a pawl camming surface (124, 126) rotatably secured to the vial, said resilient means for resiliently urging the pawl in selective engagement with said vial ratchet teeth and with said housing ratchet teeth in response to said axial displacements of the vial to the bore distal end. 4. The device of any of claims 2, 3, characterized in that the ratchet means includes a tab (102) fixed to the vial with a first cam surface (100), the housing bore having first (46) and second (62, 66) axial grooves, one (46) of the grooves for axially guiding the tab (102) during the vial displacement, the pawl (122) rotatably secured to the vial having a second cam surface (124), the pawl being in the one groove in the initial retracted position and being cammed into engagement with said vial ratchet teeth and with the housing ratchet teeth by the engagement of the tab first cam surface with said pawl camming surface (124). 5. The device of any of claims 3 and 4, characterized in that the vial ratchet teeth (112, 112') cam the pawl (122) out of engagement with the housing ratchet teeth (72, 74) in the extended position into engagement with the second groove (62, 66) for retracting the vial to the second retracted position in response to said urging. 6. The device of any of claims 3, 4 and 5, characterized in that the ratchet teeth, pawl and tab ramming surfaces comprise complementary surfaces. 7. The device of any of claims 4, 5 and 6 including tab and pawl locking means (10, 100) coupled to the second groove (62, 66) at the housing bore proximal end for permanently automatically locking the vial retracted. 8. The device of any of claims 4 through 7, characterized in that locking means are included comprising a slot (46) in the housing bore (23) coupled to the second groove (62, 66) for receiving the tab (102) and pawl (122) and having a locking recess (60) extending in the distal end direction (108) to rotationally and axially secure the pawl therein to preclude axial displacement of the vial (8) to the distal end. 9. The device of claims 4 through 8, characterized in that a plurality of said ratchet means are circumferentially spaced about the vial periphery and about the bore and first and second grooves. 10. The device of claim 1 characterized in that said positioning means includes cam means (42, 44, 10, 100) secured to the vial and housing bore responsive to the axial position of the vial in the bore for causing releasable locking of the vial, unlocking of the vial and then permanently locking of the vial (8) in the retracted position. 11. The device of claim 10 wherein the cam means comprises at least one cam surface (76, 82) on an interior surface of said housing in the cavity and at least one cam surface (116, 118, 119, 116', 118') on the vial. 12. The syringe of claim 11 wherein the housing cavity has a wall with first and second spaced axially extending grooves (46, 62, 66), the at least one cam surface on the housing comprising an undulating surface (76, 78, 82) extending circumferentially to the grooves facing the distal bore end and forming a trough (80) medially the grooves, the at least one cam surface (116, 118, 119, 116', 118') on the vial comprising an undulating surface facing in the same axial direction as the at least one cam surface on the housing, and pawl means (122) movably secured to the vial (8) for selective axial displacement in one groove at a time and for selective rotation about the vial in response to selective engagement with said at least one cam surface (116, 118, 116', 118', 119) on the vial, said housing cam surface trough (80) cooperating with the pawl means (122) for selectively retaining the vial in a needle extended position, one of said grooves (62, 66) for receiving the pawl means in response to further axial displacement of the vial and for permitting the vial to retract to the retracted position. 13. The device of claims 10, 11 and 12 characterized in that said cam means comprises cooperative ratchet and pawl means. 14. The device of claims 1 through 13 characterized in that the initial and subsequent displacements are in the same axial direction (108). 15. The syringe of claims 1 through 14 characterized in that the vial (8) has a first finger grasping flange (90) and the housing has a second finger grasping flange (24), said first flange for displacing toward the second flange in said initial and subsequent displacements. 16. The syringe of claims 1-15 characterized in that means (122, 124, 52, 60, 62, 64) are at the retracted position for permanently and automatically locking the vial retracted. 17. The device of claims 1-16 characterized in that a plunger (8) is releasably secured in the vial chamber (86) for selectively displacing the vial toward the distal end and for forcing fluid in the vial through the needle (36), the positioning means for displacing the plunger and vial (8) to the retracted position in response to said unlocking and permanently locking the vial in the retracted position.