JPS6013676Y2 - Retractable ballpoint pen - Google Patents

Description

[Detailed Description of the Invention] The retractable ballpoint pen has a hole that is slightly larger than the tip so that the tip can easily pass through the hole at the tip of the barrel and smoothly move in and out.

For this reason, the tip oscillates during writing, impairing the writing feel and sometimes producing abnormal noises.

Furthermore, if an attempt is made to prevent the above-mentioned swinging, extremely precise machining is required, which increases the price of the ballpoint pen.

Therefore, the present invention extremely easily prevents the deterioration of the writing feel due to the swinging of the tip.

FIG. 1 is a side view of a part of the embodiment of the present invention, in which a shaft cylinder 1 can be separated into a front shaft and a rear shaft by a screw 2.
An inner cylinder 3 is fitted to the front shaft.

A step portion 4 is provided inside this inner cylinder 3, and a spring 6 is stretched between the ink tube holder 5 of the feeding mechanism provided inside the rear shaft and the step portion, and a knock of the feeding mechanism is provided. A rod 7 is made to protrude from the tail end of the barrel.

The base of the ink tube 8 is detachably fixed to the holder 5, and when the knock bar 7 is pushed, the tip 9 at the tip of the ink tube protrudes from the tip of the barrel 1. When the knock bar is pushed again, the tip 9 protrudes from the tip of the barrel 1. This is designed to be stored inside the barrel.

FIG. 2 is an enlarged view of the tip of the shaft cylinder 1 in FIG. 1. The inner tube 3 has a hole 10 with a diameter slightly larger than the ink tube 8, and the tip has a hole 11 that is sufficiently larger than the tip 9. It is.

FIG. 3 is a side view of the above-mentioned ballpoint pen with the holder 5 and the ink tube 8 attached thereto taken out from the barrel, and the holder 5 slides coaxially into the barrel 1. However, the holder 5 is provided with an ink tube insertion hole 12 that is slightly inclined, and the tail portion of the ink tube 8 is fitted therein.

Therefore, the axis of the holder 5, that is, the axis a of the cylinder 1 and the axis A of the ink tube 8 form a slight angle θ and do not coincide with each other.

FIG. 4 shows the holder 5 and the base of the ink tube 8 in another embodiment of the present invention, in which the hole 12 is offset by a minute distance d from the axis a of the holder.

That is, in this embodiment, the ink tube 8 is made of metal or thick synthetic resin and is relatively hard, and the axis of the ink tube is parallel to the axis a of the barrel, but is offset by a distance d.
They don't match.

When the above-mentioned holder 5 is inserted into the barrel 1 together with the ink tube 8, the ink tube 8 is elastically bent because the axis a of the barrel does not match the axis a of the ink tube 8. The ink tube is fitted into the hole 10 of the inner cylinder, and the ink tube is pressed against one side wall of the hole 10 with a force as indicated by the arrow P, so that a minute gap δ is formed between it and the opposite side wall. Ru.

In this way, the present invention has the ink tube insertion hole 1 in the holder 5.
2 so that its axis does not coincide with the axis a of the barrel, and the ink tube 8 is attached to the holder 5 so that the axis a does not coincide with the axis a of the ink tube. The ink tube is elastically bent by the bending of the ink tube and comes into pressure contact with the inner surface of the hole at the tip of the barrel.

Therefore, when writing with such a ballpoint pen, the tip remains fixed to the barrel unless the force q applied to the tip 9 due to friction with the paper surface is opposite to and greater than the aforementioned force p. do.

Further, even if the force q becomes extremely large, the tip moves at a slow speed as the force q increases and comes into contact with the inner surface on the opposite side of the hole.

Therefore, the tip and the like do not impact against the inner surface of the hole at the tip of the barrel, and the writing feel is therefore significantly improved.

Moreover, since the friction between the inner surface of the hole and the ink tube, etc., caused by the feeding and feeding operations of the chip is a constant value determined by the degree of mismatch between the axes a and b, the force of the spring 6 should be made sufficiently larger than this value. It works reliably.

[Brief explanation of the drawing]

FIG. 1 is a side view of a part of the embodiment of the present invention, FIG. 2 is an enlarged view of a part of FIG. 1, and FIG. 3 is a side view of a part of FIG. FIG. 4 is a diagram corresponding to a part of FIG. 3 in another embodiment of the present invention. In the figure, 1 is a shaft cylinder, 2 is a screw, 3 is an inner cylinder, 4 is a step, 5 is a holder, 6 is a spring, 7 is a knock rod, 8 is an ink tube, and 9 is a tip.

Claims (1)

[Scope of utility model registration request] An ink tube insertion hole having an axis that does not coincide with the axis of the barrel is formed in the ink tube holder of the chip feeding mechanism, and the base of the ink tube is fitted into the insertion hole so that the axis of the ink tube does not coincide with the axis of the barrel. and the tip or tip of the ink tube comes into pressure contact with the inner surface of the hole at the tip of the barrel so that the tip at the tip protrudes from the hole at the tip of the barrel while the ink tube is elastically bent. A retractable ballpoint pen.