Patent GB-746057-A (GB)
Title: Improvements in or relating to syringes
IPC: A61M3/00
Filed: 1953-07-14
Abstract: 746,057. Surgical syringes. CAMBER, B. July 9, 1954 [July 14, 1953; Jan. 18, 1954], Nos. 19549/53 and 1519/54. Class 81(2). A syringe comprises a cylindrical barrel having a longitudinal groove in the wall of the bore and extending from the front or discharge end to a point short of the rear end of the barrel and a closed hollow cylindrical plunger slidable and rotatable in the barrel and having in the cylindrical wall a port near the front end registrable with the groove, a closable opening being provided at the rear end of the plunger and the barrel having a closable outlet. The glass hypodermic syringe barrel 1 is provided with a longitudinal groove 11 with which a port 20 in the cylindrical hollow glass plunger 15 is registrable. A second longitudinal groove 13 at the rear end of the barrel and diametrically opposite the first longitudinal groove 11 is provided with which a second port 21 in the plunger 15 is registrable. The rear end of the plunger 15 is provided with a removable stopper which may be made of nylon. The barrel 1 is provided with an offset nipple 3 having a bore 4. A stop cock 6 having a lever for opening and closing the barrel outlet is mounted on the nipple 3. A nozzle 8 for carrying a needle is provided on the stopcock 6. In use, with the ports 20, 21 in the plunger 15 not in register with the grooves 11, 13, the plunger 15 is retracted to draw medicament into the barrel 1 through the stopcock 6 and nipple 3. The syringe may then be used in a normal fashion or on rotating the plunger. 15 so that the ports 20, 21 register with their corresponding grooves 11, 13 and closing the stopcock 6, the plunger 15 may be projected so that medicament flows from the barrel 1 into the interior of the plunger 15 for storage purposes. Alternatively the stopper may be removed and medicament poured directly into the plunger 15. If the filled plunger 15 is retracted with the ports 20, 21 in register with their corresponding grooves 11, 13 and stopcock 6 closed, medicament flows into the barrel 1 from which it may be expelled through the needle when the plunger 15 is projected with the ports 20, 21 out of register with the grooves 11, 13. A longitudinal line is marked on the barrel to indicate the position of the groove 11 which extends from the discharge end of the barrel 1. In an alternative construction (not shown) the stopper in the rear end of the plunger is provided with a valve member which may be opened or closed, the provision of the second port 21 and the second groove 13 not then being necessary. According to the first Provisional Specification the barrel is provided with a laterally extending nipple for the attachment of a stopcock and a needle. According to the second Provisional Specification the closed inner wall of the plunger slopes towards a port so that liquid can drain out of the plunger into the syringe barrel. An adaptor and a tap portion fitted over the barrel nipple for closing the barrel outlet and mounting the needle may both be made of permanently magnetized material or may be connected by a spring catch. The plunger cavity may be in permanent communication with a reservoir of medicament by a conduit attached to the rear end of the plunger.