JPH0840443A - Extruding plunger in cylindrical vessel for viscous fluid - Google Patents

Abstract

PURPOSE:To enhance the sealing performance of a plunger to extrude a caulking material from a caulking tube. CONSTITUTION:A hollow pyramidal cylindrical rib 24 is protruded inwardly at the nearby position of the bottom plate 22 in the cylinder 21 of a plunger. Reinforcing ribs 26 are radially formed at the inside face of the bottom plate in the plunger 14. When the caulking material is extruded from the plunger 14, since the widening action of the cylinder 21 can be secured due to the deformation of the cylindrical rib 24 in the condition that the bottom plate 22 is prevented from deforming, the cylinder 21 can be strongly pressed on the inner peripheral face of the caulking tube 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a plunger slidably inserted in a cylindrical container to push out a viscous fluid, for example, when pushing out a caulking agent from a caulking pipe.

[0002]

2. Description of the Related Art A caulking agent used for repairing buildings is filled in a cylindrical caulking pipe having a discharge port formed at one end and an opening at the other end, and the caulking pipe has an opening at the other end. A plunger made of synthetic resin is fitted from the part. Then, the caulking pipe is attached to a dedicated gun, and the rod attached to the gun pushes the plunger toward one end of the caulking pipe to push out the caulking agent.

Most of the conventional plungers for caulking pipes are merely formed into a bottomed cylinder shape in which a cylinder portion 21 'and a bottom plate portion 22' are connected as shown in FIG. 6 (a). The inner surface of the bottom plate portion 22 'is directly pushed by the gun rod 27. On the other hand, as shown in FIG. 6B, the bottom plate portion 22 ″ is formed in a forward convex shape,
While forming a cylindrical stopper 25 ″ on the inner surface of the central portion of the 2 ″, a hollow cone whose radius decreases toward the opening of the tubular portion 21 ″ on the inner surface of the connecting portion of the tubular portion 21 ″ and the bottom plate portion 22 ″. A cylindrical rib 24 ″ is projected, and the cylindrical rib 24 ″ is attached to the rod 27.
It is also configured to press with.

[0004]

Problems to be Solved by the Invention As shown in FIG.
In the configuration in which the plunger 14 'is merely formed into a bottomed cylinder, when the plunger 14' is pushed by the rod 27, the outer peripheral portion of the bottom plate portion 22 'is bent and deformed by the pressure of the caulking agent, and the caulking is performed. There is a problem that the agent frequently leaks backward between the plunger 14 'and the caulking pipe 1. On the other hand, as shown in FIG. 6B, when the bottom plate portion 22 ″ is formed in a forward convex shape and the tubular rib 24 ″ is formed, the bottom plate portion 22 ″ becomes flat due to the pressure of the caulking agent. By deforming and bending the tubular rib 24 ″, the front end portion of the tubular portion 22 expands and deforms, so that the sealing function is improved as compared with FIG. 6A.

In the configuration of FIG. 6B, however, the bottom plate portion 22 "may be bent and deformed in a forward concave shape due to the pressure of the caulking agent, as shown by the alternate long and short dash line. The effect of pushing outwards the radius was incomplete, and the sealing function was not always sufficient. The present invention has been made in view of the problems of the related art, and an object thereof is to provide a plunger having an improved sealing function.

[0006]

SUMMARY OF THE INVENTION The plunger of the present invention comprises:
The basic configuration in which the tubular portion slidably fitted in the tubular container and the bottom plate portion connected to the end portion of the tubular portion near the discharge port are formed into a bottomed tubular shape is the same as the conventional one. In addition to this, in addition to this, “a hollow trapezoidal cylindrical rib whose diameter is reduced toward the opening of the cylindrical portion is provided at a portion of the inner peripheral surface of the cylindrical portion in the vicinity of the bottom plate portion. Then, the rod is set so as to abut the tip of the tubular rib, while a plurality of radially extending reinforcing ribs are formed on the inner surface of the bottom plate portion. "

[0007]

By the way, when a viscous fluid such as a caulking agent is extruded from the cylindrical container, the viscous fluid located near the axis of the cylindrical container is extruded mainly toward the discharge port, and is located outside the radius. The viscous fluid is pushed back toward the plunger.In other words, the viscous fluid circulates in the cylindrical container.Therefore, a large pressure acts on the bottom plate of the plunger near the outer circumference. Then, it is considered that a phenomenon in which the bottom plate portion flexes and deforms occurs as shown by a dashed line in FIG.

On the other hand, according to the structure of the present invention, the cylindrical rib is pushed and bent by the pressing by the rod, so that the cylindrical portion is radially outwardly expanded at the base portion of the cylindrical rib. By forming reinforcing ribs that extend radially in the part, the bottom plate does not bend and deform backward convexly due to the pressure of viscous fluid, so the deformation of the tubular rib is used to push the cylinder outwards in the radial direction. The spreading function is ensured, and as a result, the state in which the tubular portion is in close contact with the inner peripheral surface of the tubular container can be maintained.

Therefore, according to the present invention, the viscous fluid can be pushed out to the end without leaking. Further, when the annular projection is formed on the outer peripheral surface of the tubular portion as in claim 2, when the tubular rib is deformed and the tubular portion is subjected to the spreading action, the pressing force due to the spreading action acts on the annular protrusion. Since the annular projections act intensively and come into close contact with the inner peripheral surface of the cylindrical container, there is an advantage that the sealing function can be further improved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment in which the present invention is applied to a plunger for a caulking pipe will be described with reference to the drawings (FIGS. 1 to 5). In these figures, reference numeral 1 is a caulking tube made of a hard or relatively hard synthetic resin such as high density polyethylene. A shoulder portion 2 is formed at one end of the caulking pipe 1, and a cylindrical discharge port 3 is connected to the shoulder portion 2. A male screw 4 is formed on the outer peripheral surface of the discharge port 3.

The tip of the discharge port 3 is closed by a cover plate 5, and an annular weakening line 6 is formed on the cover plate 5 to form a cover plate 5.
A projection 7 having a cross shape in plan view is provided on a portion of the outer surface (upper surface) surrounded by the weakening line 6, and the projection 7 is bent in a direction intersecting the axis line to move the lid plate 5 to the weakening line. It is designed to be opened by breaking at 6 points. Reference numeral 8 is a cap fitted to the discharge port 3 of the caulking pipe 1,
This cap 8 has a cylindrical portion 8 having an internal thread 9 formed on its inner peripheral surface.
It is composed of a and a nozzle portion 9b having a tapered shape, and an appropriate portion at the tip of the nozzle portion 9b is cut to form a caulking agent spout.

Next, the plunger 14 for extruding the caulking agent will be described with reference to FIGS. The plunger 14 is formed in a bottomed tubular shape by a tubular portion 21 slidably fitted in the caulking pipe 1 and a bottom plate portion 22 connected to one end thereof. The tubular portion 21 is formed to have a diameter smaller than the inner diameter of the caulking pipe 1, and three annular projections 23, which are in contact with the inner circumferential surface of the caulking pipe 1, are formed on the outer peripheral surface of the tubular portion 21 at substantially equal intervals. Has been done.

The bottom plate portion 22 of the inner peripheral surface of the tubular portion 21
A hollow trapezoidal (or trumpet-shaped or funnel-shaped) tubular rib 24 having a diameter that decreases toward the opening of the tubular portion 21 is provided in the vicinity of the diagonally inward direction. The one of the three annular projections 23 located near the bottom plate 22 is located slightly rearward of the root of the tubular rib 24 (the annular projection 23 at the front end is located near the root of the ring 24). I'll do it). The bottom plate portion 22 is formed in a flat plate shape,
A small-diameter stopper 25 protruding toward the inside of the tubular portion 21 is formed at the center of the bottom plate portion 22. Also,
On the inner surface of the bottom plate portion 22, a plurality of reinforcing ribs 26 that radially extend around the stopper 25 are formed.

In this embodiment, eight reinforcing ribs 26 are formed (preferably a plurality of three or more), and the protruding height is set to be smaller toward the outer side of the radius. Further, the tips of the respective reinforcing ribs 26 are not continuous with the tubular portion 21, and there is a slight gap e2 between the tips of the reinforcing ribs 26 and the tubular portion 21 (FIG. 3A). reference).

In the structure of this plunger 14, the caulking agent is pushed out from the cap 8 by pressing the cylindrical rib 24 of the plunger 14 with the pressing rod 27 of the gun. In this case, as the caulking agent, as shown by an arrow E in FIG. 5, the caulking agent located near the axis of the caulking tube 1 is mainly pushed into the cap 8, and the caulking agent located on the outer side of the radius is indicated by an arrow in FIG. As shown by F, a phenomenon of pushing back toward the rear side occurs, in other words, a phenomenon in which the caulking agent circulates in the caulking pipe 1, and therefore a large pressure (reaction force) is exerted on the outer peripheral portion of the plunger 14. It works.

In the plunger 14 of the present invention, however, the hollow trapezoidal cylindrical rib 24 is pushed and bent forward so that the cylindrical portion 21 is radially outward at the base of the cylindrical rib 24. Due to the tendency of being pushed out, the annular projection 23 comes into close contact with the inner surface of the caulking tube 1, and as a result, the caulking agent is transferred to the plunger 14.
It is possible to prevent the film from protruding backward from between the caulking pipe 1 and the caulking pipe 1.

In this case, the tip end of the reinforcing rib 26 is the cylindrical portion 21.
Therefore, the cylindrical portion 21 is allowed to expand and deform outward in the radial direction. Further, since the reinforcing rib 26 is formed on the bottom plate portion 22 of the plunger 14, the bottom plate portion 22 is not bent and deformed in a backward convex shape by the pressure of the caulking agent, and the annular projection 23 is closely attached to the caulking pipe 1. The state of being kept is held.

Therefore, the caulking agent can be extruded to the end without leaking. In this case, as shown by the one-dot chain line in FIG. 5, the bottom plate portion 22 may be formed in a forward convex shape with a gentle curvature. On the other hand, as shown in FIG. 6 (a), when the plunger 14 'is merely a cylinder with a bottom, the bottom plate 22' is caused by the pressure of the caulking agent.
There is a problem in that the caulking agent often bends and deforms and the caulking agent leaks backward from between the plunger 14 ′ and the caulking pipe 1.

Further, as shown in FIG. 6B, the bottom plate portion 2
When the cylindrical ribs 24 "are formed while the 2" is formed in the forward convex shape, the bottom plate portion 2 is formed by the pressure of the caulking agent.
By deforming 2 ″ into a flat plate shape and pressing and bending the tubular rib 24 ″, the front end portion of the tubular portion 22 expands and deforms, and the sealing function is improved as compared with the case of FIG. 6A. In this case, as shown by the alternate long and short dash line, the bottom plate portion 22 ″ may be bent and deformed due to the pressure of the caulking agent, which may result in an incomplete spreading action of the tubular portion 21 ″ and a sealing function. It wasn't enough. The plunger 14 according to the present invention can remarkably improve the sealing function in comparison with those shown in FIG.

[Brief description of drawings]

FIG. 1 is a perspective view of a caulking tube.

FIG. 2 is a vertical cross-sectional view in which a caulking tube and a cap are separated.

3A and 3B are cross-sectional views of the main part of the plunger, in which FIG. 3A is a view before being pushed in, and FIG.

4 is a sectional view taken along line IV-IV of FIG.

FIG. 5 is a view showing the action of the plunger.

FIG. 6 is a view of a conventional plunger.

[Explanation of symbols]

 1 Caulking tube as an example of a cylindrical container 8 Cap 14 Plunger 21 Tube part 22 Bottom plate part 23 Annular protrusion 24 Cylindrical rib 25 Stopper 26 Reinforcing rib

Claims (2)

[Claims] 1. In order to push out a viscous fluid filled in a cylindrical container having a discharge port formed at one end and an opening at the other end from the discharge port, the cylindrical container is fitted into the cylindrical container through an opening at one end thereof. A plunger adapted to be pushed and moved by a rod from the outside toward one end of the tubular container, wherein the plunger includes a tubular portion slidably fitted in the tubular container, and a discharge port of the tubular portion. It is formed in a bottomed tubular shape with a bottom plate portion connected to the end nearer, in a portion of the inner peripheral surface of the tubular portion in the vicinity of the bottom plate portion,
A hollow trapezoidal cylindrical rib whose diameter decreases toward the opening of the cylindrical portion is provided so as to project so that the rod abuts on the tip of this cylindrical rib, while the inner surface of the bottom plate portion is radially formed. A plurality of reinforcing ribs extending in the direction are formed, and a pushing plunger for a viscous fluid cylindrical container. 2. The "diameter according to claim 1", wherein the outer diameter of the tubular portion is set to a size such that a gap is formed between the outer diameter of the tubular portion and the inner circumferential surface of the tubular container. For viscous fluid, characterized in that an annular projection that is in close contact with the inner peripheral surface of the tubular container is formed in the vicinity of the base of the annular rib and at a plurality of locations located closer to the opening edge of the tubular portion than that. A plunger for pushing out in a cylindrical container.