Showa Yakuhin Kako Co., Ltd.

Other

Gc Showayakuhin Corporation

Renji Hayashi

Fumio Tanaka

Mutsumi Shibuya

Mitsuhiro Haraguchi

Yoshihiko Kawasaki

Yoshinori Kato

Yoshinori Katoh

Yukio Kawagishi

Kiyoshi Wakabayashi

Ikuo Kitagawa

Yoshihiko (deceased) Kawasaki

Provided is an anesthetic solution-filled cartridge-type electric dental syringe, wherein the plunger has been shortened but the plunger can nevertheless be extended to the distance necessary to evacuate the anesthetic solution from the cartridge. The syringe comprises: an extension tube into which a plunger is movably inserted, the extension tube being movably disposed in the through hole of a support block and having racks formed in the side surface thereof that are coordinated with the racks of the plunger; and a means for the plunger to draw the extension tube to engage the racks of the extension tube with a pinion when the plunger reaches the middle of the distance corresponding to the anesthetic solution accommodation length of the cartridge. By the engagement of the racks of the extension tube with the pinion, the plunger moves together with the extension tube for the remainder of the distance corresponding to the anesthetic solution accommodation length of the cartridge.

Anesthetic solution-filled cartridge-type electric dental syringe

A motorized syringe for use with two types of dental anesthetic solution-filled cartridges, having a plunger plug in the 1.8 ml cartridge pushed by a push rod by a length required to push a plunger plug in the 1.0 ml cartridge. The syringe includes a cartridge holder for use with 1.0 ml and 1.8 ml cartridges, the push rod having a 1.0 ml position and a 1.8 ml position drawn back from the 1.0 ml position so that push rod movement can end at a common terminal position for both, a sleeve adapted to receive the push rod rear end when pushed back from the common terminal position, and to be not interfered with by the push rod's rear end when it is in the 1.0 ml position, the sleeve being pushed rearward with the push rod's rear end when pushed back to the 1.8 ml position.

Motorized syringe for use with two types of dental anesthetic solution-containing cartridges

A linear cartridge-type motorized dental syringe has a plunger rod aligned with a drive shaft of a motor, the externally threaded plunger rod movable longitudinally, but not rotatably, relative to the casing, a cylindrical body rotated by the shaft, a nut having arm-like nut halves with internal threads engaging external threads on the rod, a locking ring for rotation around an axis of the rod and for longitudinal movement between a rearward position where the ring forces the threads on the nut halves to engage the threads on the rod, and forward where the ring releases engagement of the threads, pusher pins for moving the ring rearward when the cartridge holder is inserted, and a spring for pushing the locking ring back to the forward position, with rotation of the cylinder body resulting in rotative motion of the nut around the rod to move it forward.

Linearly motorized dental syringe

An electrically-driven dental injector used in orally injecting such an injection liquid as an anesthetic in dental treatment. Electrically-driven dental injectors includes one having a mechanism for disengaging a pinion ( ) from a rack ( ) in order to retract a plunger rod ( ) upon completion of injection; however, it has heretofore been necessary to manually operate the operating part from outside each time. The inventive electrically-driven dental injector is so arranged that the plunger rod can be manually pushed back directly oupon completion of injection without requiring manual operation, and, to this end, the injector comprises a latch mechanism ( ) for engaging/disengaging the ring gear ( ) of a planetary reduction gear ( ) with/from a casing ( ), and an operating rod ( ) extending through a support member ( ) and functionally cooperating with the latch mechanism ( ).

Electrically-driven dental injector

Growing community of inventors

Matsudo, Japan

Renji Hayashi