Viscous material extruding dispenser
AssigneesKuraray Noritake Dental Inc., Yoshino Kogyosho Co., Ltd.
InventorsHideto Kunishi, Yasujiro Ohara, Katsuhito Kuwahara, Toru Toma, Satoshi Sakamoto
Life of this patent
Estimating the term…
Abstract
A syringe has a dripless feature by using an O-ring located between a conical disc and a flat plunger disc in an annular groove on a moving plunger. The flat plunger disc has a series of projections that offset the o-ring off the flat plunger disc surface when the plunger is not actuated. When the plunger is actuated, the o-ring distorts to rest on the projections and also on the surface of the flat plunger disc. When the plunger is released, the o-ring's resiliency pulls the o-ring back to its original shape which sucks back the fluid being dispensed so that no or less drips occur.
Claims9
A dispenser for extruding a viscous material, the dispenser comprising:
- a syringe body having a space for filling contents and equipped with an extruding nozzle at a front end thereof,
- a plunger that can slide in the syringe body by a pressing force applied thereto in order to extrude the contents in the filling space from a tip of the extruding nozzle,
- an O-ring placed in an annular groove formed in a front end section of the plunger and slidable on an inner wall surface of the syringe body, wherein the annular groove is formed as a recess having a flat bottom wall and defined by a conical disc that is arranged at a front end of the plunger and a pressing disc that is spaced backwardly from the conical disc, and wherein the O-ring contacts directly with the flat bottom wall, and
- a plurality of projections or grooves formed on the pressing disc at intervals therebetween so that a side portion of the O-ring comes into contact with the sidewall of the annular groove, is elastically displaced and then compressively deformed upon pressing and so that the O-ring is restored upon releasing a load applied for pressing the plunger to slide the plunger in a direction opposed to the pressing direction, thus inducing back suction of contents.
Dependencies are inferred from the claim text.