STOPPER FOR SYRINGE FOR SETTING VARIABLE AMOUNT OF DISCHARGE

PROBLEM TO BE SOLVED: To provide a stopper for syringe that can easily set the amount of discharging chemical, for example, insulin and so on. SOLUTION: The stopper 2 is set at main body 101 of a syringe or adjusting tip 102. While the amount of a chemical being discharged is being set, the stopper 2 that is set to some part of indicator 105 prevents the adjusting tip 102 from being screwed too much. After the adjusting tip 102 that determines the amount of a stroke by piston rod 103 determines the amount of the chemical being projected by being properly screwed, releasing button 104 is slid. Then, while the piston rod 103 is projected as it is determined, the adjusting tip 102 returns to the first position (the position that indication 105 is coincided with indication 106) automatically by the power of spring. Piston 108 inside cartridge 107 is pushed forward by the piston rod 103, then the chemical, for example, insulin and so on, of which amount has been set can be discharged from the needle 109.