JPH0221263Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a water-based ink ballpoint pen that has a simple structure to prevent ink from overflowing from the ink storage body to the outside of the barrel, and also ensures smooth ink flow to the ball portion.

2. Description of the Related Art Water-based ink ballpoint pens have been widely known in the past, which have a structure in which ink is supplied from an ink absorbing body housed in a barrel and covering the areas other than the front and rear ends to a ball portion through an ink guiding core. However, in this type of water-based ink ballpoint pen, the ventilation hole that communicates with the ink storage body is usually bored at the tip of the barrel due to the position of the cap in the writing state. Since the front end of the ink storage body where the ink guide wick is buried is not covered, there may be an imbalance in the air pressure between the ink storage body and the outside world caused by changes in temperature, or when the ballpoint pen holder is facing downward. When some kind of impact is applied to the writing instrument, the ink in the ink storage body leaks into the barrel, and eventually leaks out of the barrel through the ventilation hole, causing a problem. This proposal is intended to eliminate the drawbacks seen in this prior art, and
As a solution to this problem, a shielding part for preventing ink leakage is provided at the rear of the ballpoint pen holder to cover the ink absorbing body including its front end with an appropriate gap between it and the outer surface of the ink absorbing body. There is. Hereinafter, embodiments of the present invention will be described based on the drawings.

A ballpoint pen holder 2 is attached to the tip 1a of the barrel 1.
The ballpoint pen holder 2 has a ball portion 2a that rotatably holds the ball b, and also has an ink guide core holding hole 2b into which the ink guide core 3 is inserted. Ink is supplied to the ball portion 2a by an ink storage body 4 housed in the shaft cylinder 1.
One end of the ink guiding wick 3 is positioned as close as possible to the ball portion 2a, and the other end is buried in the front end 4a of the ink storage body 4. are doing.

The ink storage body 4 except for the front end 4a and the rear end 4b is covered with a suitable material such as a heat-shrinkable tube 5 or a film sheet. It is held so as to communicate with a ventilation hole 6 formed in the tip portion 1a. The communication structure with the ventilation hole 6 may be determined as appropriate. Here, a gap 1b is provided between the ink storage body 4 and the inner wall of the shaft cylinder 1, and a tail plug 7 having a notch groove 7a connects the rear end of the ink storage body 4. A structure that supports the portion 4b is adopted.

A shielding part 8 provided on the ballpoint pen holder 2 to prevent ink leakage covers the ink absorber 4 including the open front end 4a of the ink absorber 4. It is important that an appropriate gap 9 communicating into the shaft cylinder 1 is provided between the two.

The shielding part 8 is connected to the ventilation hole 6 and the front end part 4a of the ink storage body.
Of course, the insulation between the shielding part 8 and the outer surface 4c of the ink storage body 4 is ensured, but as mentioned above, the existence of the gap 9 between the shielding part 8 and the outer surface 4c of the ink absorbing body 4 prevents ink from being guided inside the shielding part 8. This is significant in relation to the space 10 surrounding the core 3. That is, this space 10 is provided in front of the front end 4a of the ink storage body in the shielding part 8, and normally nothing interferes with guiding the ink to the ball part 2a of the ink guiding core 3. Although this is intended to allow the ink absorber 4 to perform the process freely, it also becomes a place where the expanded air generated from the rise in pressure inside the ink storage body 4 accumulates, so if the rise in pressure continues for a long time, this expanded air It becomes necessary to actively secure an escape area for the shaft, and in this case, the above-mentioned gap 9 that communicates with the inside of the shaft cylinder 1 comes into play effectively.

The shielding part 8 is connected to the ventilation hole 6 and the front end part 4a of the ink storage body.
It goes without saying that the material and shape of the shielding part 8 do not matter, as long as it can maintain the shielding part 8 in an insulated state and form the gap 9 between the outer surface 4c of the ink storage body and the outer surface 4c of the ink storage body. is provided at the rear of the ballpoint pen holder 2,
The mounting structure may be determined as appropriate.

In the one shown in FIG. 1, a separate shielding part 8 is provided at the rear of the ballpoint pen holder 2.
The one shown in FIG. 5 is for the case where it is provided integrally with the ballpoint pen holder 2.

11 in the figure is a stepped portion provided in the shaft cylinder 1,
This serves to hold the shielding part 8 within the shaft cylinder 1. 1
1a is a ventilation groove formed in the stepped portion 11, which is a ventilation path P provided between the shaft cylinder 1 and the ink storage body 4.
This ensures communication between the ventilation hole 6 and the inside of the shaft cylinder 1. Further, reference numeral 12 denotes a stepped portion provided within the shielding portion 8, which serves to hold the ink storage body 4 within the shielding portion 8. The stepped portion 12 may be formed integrally with the shielding portion 8 by molding it from a relatively hard material, or alternatively, the stepped portion 12 may be formed by providing a convex portion for the stepped portion 12 on a separate member. It may also be provided by being inserted during the assembly process. Note that 12a is a ventilation groove formed in the stepped portion 12 in the shielding portion 8, which communicates the space portion 10 with the gap portion 9. If formed, a groove may be formed at the same time as the protrusion is formed on the separate member, and this groove may be used as the ventilation groove 12a. 1
Reference numeral 4 denotes an annular projection provided on the tail plug 7, which maintains airtightness when the tail plug 7 is press-fitted into the shaft cylinder 1.

As described above, the present proposal is to provide a ballpoint pen holder with a shielding part that covers the ink absorbing body including its front end with a gap between it and the outer surface of the ink absorbing body, and a space provided in the shielding part. Since the vent hole at the tip of the shaft cylinder and the front end of the ink storage body are completely shielded, the air flow from the ink storage body to the shaft cylinder is completely blocked. Water-based ink ballpoint pens that prevent unexpected situations such as ink from spilling out can now be easily obtained. Furthermore, according to the present invention, a gap is definitely formed between the shielding part and the outer surface of the ink storage body, so that the expanded air that is once stored in the space inside the shielding part does not stay inside the shielding part. Instead, alternate air flows into the shaft cylinder from the vent hole according to the amount of ink coming out, and smooth ink flow to the ball portion is ensured.

[Brief explanation of the drawing]

Figure 1 is a partially omitted side cross-sectional view illustrating a water-based ink ballpoint pen implementing the present invention, and Figure 2 is Figure 1A.
-A sectional view, Figure 3 is the BB sectional view of Figure 1, Figure 4
The figure is a sectional view taken along the line CC in FIG. 1, and FIG. 5 is an explanatory diagram of a modification of the structure for attaching the shield to the ballpoint pen holder. DESCRIPTION OF SYMBOLS 1... Shaft cylinder, 1a... Shaft cylinder tip, 2... Ballpoint pen holder, 3... Ink guiding core, 4... Ink absorber, 4a... Front end, 4b... Rear end,
6...Vent hole, 7...Tail plug, 7a...Notch groove, 8
...shielding part, 9... gap part, 10... space part, 1
1, 12...stepped portion, 11a, 12a...ventilation groove.

Claims (1)

[Scope of utility model registration request] Ink is supplied to the ball part of the ballpoint pen holder attached to the tip of the barrel from an ink storage body that is housed in the barrel and covers the areas other than the front and rear ends, via an ink guiding core. In a water-based ink ballpoint pen that has a ventilation hole in the tip that communicates with the ink storage body, the ventilation hole 6 and the rear end 4b of the ink storage body 4 are communicated with each other, and the ballpoint pen holder 2 is provided with a vent hole that communicates with the ink storage body 4. A shielding part 8 is provided which covers the ink storage body 4 including its front end 4a with a gap 9 between it and the side surface 4c. A water-based ink ballpoint pen characterized by communicating with a space 10 provided in the front.