JPH0453993Y2 - - Google Patents

Description

[Detailed explanation of the invention] "Industrial application field" This invention separates the shaft cylinder into an upper shaft cylinder and a lower shaft cylinder,
The present invention relates to an improvement of a writing instrument equipped with a so-called rotary writing body ejection/removal mechanism in which a plurality of writing bodies housed in a barrel are made to emerge and retract from an opening at the lower end of the barrel by relative rotational action between the two.

"Problems to be Solved by the Prior Art and the Present Proposal" Conventionally, a barrel is separated into an upper barrel and a lower barrel, and a plurality of writing letters are accommodated in the barrel by the relative rotation of the two. Many of the devices in which the cylindrical shafts alternately appear and retract from the opening of the shaft cylinder have the basic structure as disclosed in Japanese Utility Model Publication No. 52-40833.

In other words, inside the upper barrel by some means,
A cam member consisting of two inclined surfaces of approximately equal length from the center is attached, and a writing body which is urged toward the upper shaft cylinder and engages with the cam surface of this cam member is attached in the axial direction. The sliding case is movably mounted inside the cam member.

In this case, if the central part of the cam member is made into a cutout-shaped writing locking part, and the sliding case is made to operate integrally with the lower barrel, the rotational movement of the lower barrel or the upper barrel can be used. The writing state or the released state is obtained by alternately engaging and disengaging the writing body that engages with the cam surface of the cam member with the locking portion of the cam member against the biasing force.

However, even with this relatively reasonable approach, there are some problems. First, since the cam member is a separate and independent entity, it is complicated in that consideration must be given to the mounting structure of the cam member to the upper shaft cylinder. In addition, even if the mounting structure is such that the sliding case is movably mounted inside the cam member,
It is not so easy to prevent separation from the cam member while ensuring its mobility.

``Means to solve the problem'' This proposal not only increases the number of parts, but also complicates the workability in the assembly process, which ultimately leads to an increase in costs. The invention is intended to improve a writing instrument equipped with a writing instrument, in which a cam portion having a cam surface with which a writing body engages is formed on the inner wall surface of the upper barrel, and
A sliding case that engages with the cam part and is installed in the upper shaft cylinder has a large diameter part and a small diameter part, the small diameter part is connected to the lower shaft cylinder so that it can operate integrally, and the end face of the large diameter part has a large diameter part and a small diameter part. A means to solve the problem is to bring the bent part of the ring member fixed to the upper barrel into contact with the end face of the bent part and the end face of the lower barrel so that a gap is created. .

"Function" According to the present proposal, the sliding case that engages with the cam portion and is installed in the upper shaft cylinder is connected to the lower shaft cylinder at its small diameter portion so as to be able to operate integrally, and also connects to the end face of the large diameter portion. The bent part of the ring member fixed to the upper barrel is brought into contact with the lower barrel so that a gap is created between the ring member and the lower barrel, ensuring rotational operation of the sliding case and preventing separation from the upper barrel. Therefore, it is now possible to easily obtain a writing instrument with a rotary writing body ejection mechanism that is easy to work with and has a simple structure.

"Example" Hereinafter, an example of the present invention will be described based on the drawings.

The barrel 1 is separated into an upper barrel 1a and a lower barrel 1b, and a cam portion 2 for projecting and retracting a writing body is formed on the inner wall surface of the upper barrel 1a. The cam portion 2 has cam surfaces 2a and 2b formed of inclined surfaces having approximately equal lengths on both sides around a notch-shaped writing locking portion 2c provided at the center.

A plurality of writing bodies 4, 5 housed in the sliding case 3 engage with the cam surfaces 2a, 2b as described later. The writing bodies 4 and 5 housed in the sliding case 3 are urged toward the upper end 1c of the shaft cylinder and are movable only in the axial direction, and an example of their specific structure is as follows. It is. The writing bodies 4 and 5 are sliding parts of the writing body that engage with the cam surfaces 2a and 2b of the cam part 2 from slit parts 3c and 3d extending in the axial direction formed in the sliding case 3. The movable parts 4a and 5a are exposed and are housed in a state where they are always biased toward the upper end 1c of the shaft cylinder by the elastic force of the coil springs 6a and 6b.

The sliding case 3 has a large diameter portion 3a and a small diameter portion 3.
b, and enables integral operation with the lower shaft cylinder 1b via the small diameter portion 3b, but both 3b, 1b
Considering the convenience of exchanging cursive letters 4 and 5,
Preferably, they are separably connected.

Here, both 3b and 1b are connected by screw fitting, but the length of the screw thread is adjusted and the writing 4,
During the prototyping process, it was confirmed that by adjusting the setting of the inclination angle of the cam surfaces 2a and 2b of the cam portion 5 engaged with, the alternating protrusion and retraction of the writing bodies 4 and 5 due to the rotational operation of the lower barrel 1b would not be hindered. This has been confirmed in operational experiments.

Note that the separable connection structure between the two parts 3b and 1b is not limited to screw fitting, and may be, for example, press fitting.

Reference numeral 7 denotes a ring member having a through hole 7b having an inner diameter larger than that of the small diameter portion 3b of the sliding case 3, and this ring member 7 is formed on the end surface 3a' of the large diameter portion 3a of the sliding case 3. It has a bent portion 7a that comes into contact with it.
After the sliding case 3 containing the writing bodies 4 and 5 is mounted in the upper barrel 1a, the ring member 7 is inserted from the direction of the small diameter portion 3b of the sliding case 3 through the through hole 7b.
The bent portion 7a is inserted and fixed to the upper shaft cylinder 1a until it comes into contact with the end surface 3a' of the large diameter portion 3a of the sliding case 3. Of course, this fixing means may be determined as appropriate.

After securing the separation of the sliding case 3 from the upper shaft cylinder 1a by the abutting action between the bent portion 7a of the ring member 7 and the large diameter end surface 3a' of the sliding case 3, the lower shaft cylinder 1b is secured. is integrally and operatively connected to the small diameter portion 3b of the sliding case 3. At this time, it is important to ensure that there is a gap between the end surface 7a' of the bent portion 7a of the ring member and the end surface 1b' of the lower shaft cylinder 1b. The goal is to create an appropriate gap S.

This is because the existence of this gap S ensures the rotational operation of the sliding case 3. C is a clip member attached to the upper end portion 1c of the shaft cylinder.

"Effects of the Idea" As described above, the present invention attaches the lower shaft cylinder to the small diameter part of the sliding case so that it can be integrally operated, and the bent part of the ring member fixed to the upper shaft cylinder is attached to the end face of the large diameter part. Since the end face of the contact bending part and the end face of the lower shaft cylinder are brought into contact so as to form a gap, rotational operation of the sliding case can be easily ensured, and It is easy to prevent the sliding case from coming off the upper barrel, and the ring member also serves as a decorative ring to improve the aesthetic appearance of the writing instrument's exterior.

In addition, according to the present invention, since the cam part for retracting the writing body can be formed directly on the inner wall surface of the upper barrel, a writing instrument with a rotary writing body retraction mechanism that has a simple structure and high safety can be obtained. It can be obtained very easily.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view showing the entire writing instrument according to the present invention, Fig. 2 is an explanatory view showing the relationship structure between the cam part formed on the inner wall surface of the shaft cylinder and the sliding body, and Fig. 3
FIG. 4 is an enlarged explanatory view of part A in the figure, and is an explanatory view showing a state in which the ring member is inserted into the sliding case. DESCRIPTION OF SYMBOLS 1... Shaft cylinder, 1a... Upper shaft cylinder, 1b... Lower shaft cylinder, 2... Cam part, 2a, 2b... Cam surface, 3
...Sliding case, 3a... Large diameter portion, 3b... Small diameter portion, 4, 5... Cursive, 4a, 5a... Sliding part of writing, 7... Ring member, 7a... Bending Part, 7b...Through hole part, S...Void part.

Claims (1)

[Scope of utility model registration request] The barrel is separated into an upper barrel and a lower barrel, and by the relative rotation of the two, a plurality of writing fonts are urged toward the upper barrel and alternately appear and retract from the lower end opening of the lower barrel. In this writing instrument, the writing bodies 4 and 5 that engage with the cam surfaces 2a and 2b of the cam portion 2 for projecting and retracting the writing body formed on the inner wall surface of the upper barrel 1a are inserted through the lower barrel 1b and the small diameter portion 3b. , is housed in a sliding case 3 that operates integrally so as to be movable only in the axial direction thereof, has a through hole 7b larger in diameter than the outer diameter of the small diameter portion 3b of the sliding case 3, and has a bent portion. 7a is the end surface 3 of the large diameter portion 3a of the sliding case 3
a' is fixed to the upper barrel 1a so that a gap S is formed between the end surface 7a' of the bent portion 7a and the end surface 1b' of the lower barrel 1b. A writing instrument equipped with a rotating writing mechanism.