초록 ▼

A safety injection device, such as a hypodermic needle, for dispensing liquid from a cartridge in quantities determined by the length of a plunger which may be selectively adjusted in one position only of the plunger. The plunger comprises first and second threadedly connected sections cooperating w

A safety injection device, such as a hypodermic needle, for dispensing liquid from a cartridge in quantities determined by the length of a plunger which may be selectively adjusted in one position only of the plunger. The plunger comprises first and second threadedly connected sections cooperating with a connector which may be selectively activated when the plunger is moved into the one position to permit rotation of one plunger section relative to the other. Preferably, the adjustment position of the plunger coincides with its positions assumed in preparation of an injection stroke, with the connector preferably providing for undirectional rotation of the one plunger section.

대표청구항 ▼

An injection device for injecting adjustable dose of an injection liquid (13), comprising: a housing (11, 21) having a space therein for receiving a container (12) having a piston (14) displaceably arranged therein and containing the injection liquid (13); an adjustable-length plunger (29, 38) in sa

An injection device for injecting adjustable dose of an injection liquid (13), comprising: a housing (11, 21) having a space therein for receiving a container (12) having a piston (14) displaceably arranged therein and containing the injection liquid (13); an adjustable-length plunger (29, 38) in said housing, said plunger being axially displaceable in said housing between a first dosage-setting axial position and a second axial position; said plunger acting upon the piston (14) in the container (12) when said plunger moves from said first dosage setting axial position to said second axial position thereof; said plunger (29, 38) comprising adjustment means for selectively adjusting the effective length of said plunger, said plunger and adjustment means including a threaded member (38); a threaded spindle (29) guided in an interior thread (35) of said threaded member (38); a guide member (34) rotatably connected to said threaded member; means (30, 31, 36) arranged between said guide member and said threaded spindle (29) for axially guiding said threaded spindle and for preventing rotation of said threaded spindle relative to said guide member (34); enabling/disabling means (55, 56) automatically enabling said adjustment means when said plunger is in said first dosage setting axial position and automatically disabling said adjustment means when said plunger is in said second axial position, said enabling/disabling means being operatively arranged between said plunger (29, 38) and said housing (11, 21) and responsive to the axial position of said plunger relative to said housing, whereby adjustment of the effective length of said plunger by said adjustment means is automatically disabled when said plunger is in said second axial position.