EP-4736806-A1 - PASTE INJECTOR

EP4736806A1EP 4736806 A1EP4736806 A1EP 4736806A1EP-4736806-A1

Abstract

In order to provide a paste dispenser capable of determining a relative position between a syringe and an attachment member at a predetermined position, a paste dispenser includes an attachment member (M) that is detachably attached to a syringe (3) including discharge ports (51, 51'). The attachment member (M) includes a tubular external body (OM), into which the syringe (3) is inserted and which is rotatable about a central axis (CA), and an inside member (IM) that is disposed inside the external body (OM). The external body (OM) is fixed to the syringe (3) via an engagement structure configured to engage by insertion of the syringe (3) along the central axis (CA) and by rotation of the external body about the central axis (CA). The engagement structure includes at least three engagement pairs, each pair including an engaging portion (45) that is formed on the syringe (3) and an engaged portion (107) that is formed in the external body (OM) and engageable with the engaging portion (45). The at least three engagement pairs are aligned along a rotation direction of the external body (OM) and are non-point symmetrical about a central point on the central axis (CA) when viewed along the central axis (CA).

Inventors

KAWANA Mariko
NOJIRI YAMATO
ATAKA KENSUKE
MURAYAMA MOMOE
SESHIMO SATOSHI
OHDAIRA TOSHIYUKI

Assignees

Kuraray Noritake Dental Inc.

Dates

Publication Date: 20260506
Application Date: 20240624

Claims (10)

A paste dispenser comprising: a syringe that comprises a plurality of paste storage chambers filled with pastes, a plurality of discharge ports, each of which opens at one end of each of the plurality of the paste storage chambers, and a plurality of filling ports, each of which opens at another end of each of the plurality of the paste storage chambers; a plunger that is inserted into the paste storage chambers from the filling ports and is configured to push out the pastes through the discharge ports; and an attachment member that is detachably attached to a tip end portion of the syringe where the discharge ports are formed, wherein the attachment member comprises: a tubular external body into which the syringe is inserted, the external body being rotatable about a central axis of the syringe; and an inside member that is disposed inside the external body, the inside member comprising a plurality of insertion portions that are respectively inserted into the plurality of the discharge ports and being rotatable about the central axis relative to the external body, wherein the external body is fixed to the syringe via an engagement structure, the engagement structure engaging by insertion of the syringe along the central axis and by rotation of the external body about the central axis, wherein the engagement structure comprises at least three engagement pairs, each pair comprising an engaging portion that is formed on the syringe and an engaged portion that is formed in the external body and is engageable with the engaging portion, and wherein the at least three engagement pairs are aligned along a rotation direction of the external body and are non-point symmetrical about a central point on the central axis when viewed along the central axis.
The paste dispenser according to claim 1, wherein the at least three engagement pairs are aligned at non-equal intervals along the rotation direction of the external body.
The paste dispenser according to claim 1 or 2, wherein at least one of the at least three engagement pairs has a different shape when viewed along the central axis.
The paste dispenser according to claim 1 or 2, wherein one of the engaging portion and the engaged portion is formed by a recess comprising a first groove portion extending toward the central axis and a second groove portion extending from the first groove portion in the rotation direction of the external body, wherein another one of the engaging portion and the engaged portion is formed by a projection piece that is insertable into the recess.
The paste dispenser according to claim 1 or 2, wherein an outer peripheral surface of the external body has a polygonal shape when viewed along the central axis, wherein an inner circumferential surface of the external body has a circular sectional shape when viewed along the central axis, wherein at least one of the engaged portions is formed at a position corresponding to a corner portion of the outer peripheral surface, and at least one of the engaged portions is formed at a position corresponding to a flat surface portion of the outer peripheral surface.
The paste dispenser according to claim 1 or 2, wherein the inside member comprises a base portion that is fitted into the external body and on which the plurality of the insertion portions are formed, wherein the insertion portions have a columnar shape that is capable of sealing the discharge ports.
The paste dispenser according to claim 1 or 2, wherein the external body comprises a top wall portion that faces an opening portion into which the syringe is inserted, and a top through tube that is formed on the top wall portion, wherein the inside member comprises a mixing tip body and a mixer housing, wherein the mixing tip body comprises: a base portion on which the plurality of insertion portions are formed on a first end surface, and on which elements aligned along the central axis are formed on a second end surface opposite the first end surface; and paste passages that continuously penetrate the insertion portions and the base portion and open at the second end surface, and wherein the mixer housing comprises: an element housing portion into which the elements are insertable and which is open at a tip; and a base housing portion into which the base portion is fittable, wherein, when the mixer housing is combined with the mixing tip body, the element housing portion is inserted into the top through tube and is attached to the external body.
The paste dispenser according to claim 1 or 2, wherein the engaged portions are formed in the inner circumferential surface of the external body, wherein the external body comprises a cylindrical wall portion that projects beyond the engaged portions, the cylindrical wall portion having a cylindrical shape that defines an opening portion into which the syringe is inserted.
The paste dispenser according to claim 1 or 2, wherein the external body comprises a projection portion that projects along the central axis from an opening portion into which the syringe is inserted, wherein the projection portion is formed at a position that is coincident, in a circumferential direction about the central axis, with a position where one of the engaged portions is formed.
The paste dispenser according to claim 1 or 2, wherein the paste dispenser is used for injecting a paste as a dental material.

Description

[Technical Field] The present invention relates to a paste dispenser. [Background Art] It is known a dental material that is made of a plurality of types of pastes and is prepared by mixing them just before use. In order to inject such dental material into a predetermined position, there is a paste dispenser that discharges the plurality of types of the pastes while mixing them together. The paste dispenser includes a syringe that individually stores a plurality of types of pastes, a plunger that pushes out the pastes, and an attachment member that is detachably attached to discharge ports of the syringe. The attachment member is either a cap that is attached when the paste dispenser is stored or transported, or a static mixer that is for ejecting the pastes discharged from the syringe while mixing them, and the attachment member can be replaced as necessary. For example, Patent Literature 1 discloses the cap. [Prior Art Documents] [Patent Literature] [Patent Literature 1] Japanese Patent Application Publication No. 2007-504058 [Summary of Invention] [Problem to be solved] The cap disclosed in Patent Literature 1 includes an external body that is fixed to the syringe, and an inside member that is disposed inside the external body and includes insertion portions to be inserted into discharge ports. Here, a plurality of types of pastes to be mixed together by a paste dispenser undergo changes such as solidification through the mixing. Therefore, in a repeated attachment and detachment of the cap, for example, if an insertion portion to which a first paste has been attached is inserted into a discharge port from which a second paste is discharged, the first and second pastes are mixed together to generate paste changes such as solidification inside the discharge port. Also, in the static mixer, when a paste passage to be inserted into a discharge port is determined in advance, it is necessary to make the discharge port, into which the paste passage is inserted, properly match with the paste passage when attaching the static mixer. Thus, it is necessary to attach the attachment member to the syringe in a predetermined orientation. An object of the present invention is to provide a paste dispenser that is capable of determining a relative position between a syringe and an attachment member at a predetermined position when the attachment member is attached to the syringe. [Solution to Problem] A paste dispenser of the present invention includes a syringe that includes a plurality of paste storage chambers filled with pastes, a plurality of discharge ports, each of which opens at one end of each of the plurality of the paste storage chambers, and a plurality of filling ports, each of which opens at another end of each of the plurality of the paste storage chambers; a plunger that is inserted into the paste storage chambers from the filling ports and is configured to push out the pastes through the discharge ports; and an attachment member that is detachably attached to a tip end portion of the syringe where the discharge ports are formed. The attachment member includes a tubular external body into which the syringe is inserted, the external body being rotatable about a central axis of the syringe; and an inside member that is disposed inside the external body, the inside member including a plurality of insertion portions that are respectively inserted into the plurality of the discharge ports and being rotatable about the central axis relative to the external body. In order to achieve the object, the external body is fixed to the syringe via an engagement structure, the engagement structure configured to engage by insertion of the syringe along the central axis and by rotation of the external body about the central axis. The engagement structure includes at least three engagement pairs, each pair including an engaging portion that is formed on the syringe and an engaged portion that is formed in the external body and is engageable with the engaging portion. The at least three engagement pairs are aligned along a rotation direction of the external body and are non-point symmetrical about a central point on the central axis when viewed along the central axis. [Effects of Invention] According to the above configuration, the paste dispenser of the present invention can determine the relative position between the syringe and the attachment member at a predetermined position when the attachment member is attached to the syringe. [Brief Description of Drawings] [FIG. 1] FIG. 1 is a perspective view of a paste dispenser including a static mixer of a first embodiment.[FIG. 2] FIG. 2 is an exploded perspective view of the paste dispenser of the first embodiment.[FIG. 3] FIG. 3 is a sectional view of the static mixer fixed to a tip end portion of a syringe of the first embodiment, the sectional view being taken in the width direction at a position passing through a central axis extending in the longitudinal direction.[FIG. 4