JPS597115Y2 - writing implements - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement in a writing instrument that can automatically protrude and hold the necessary amount of lead for writing by simply attaching a lead protection cap to the outer case.

In conventional knock-type writing instruments, the lead is stored inside the outer cylinder when not in use, so it is always necessary to first perform a knocking motion, check the amount of protrusion of the lead, and then write. .

The object of this invention is to provide a writing instrument which eliminates the need for the above-mentioned knocking action and can protrude and hold the necessary amount of lead for next writing by simply attaching the cap for protecting the lead at the end of writing.

An embodiment of this invention will be described below with reference to the drawings.

This invention has a cap 2 for protecting the lead which is removably fitted to the tip of the outer cylinder 1, and a lead feeding part 3 which is slidably housed within the outer cylinder 1.

The outer cylinder 1 has a cylindrical shape as shown in FIGS. 1 and 2, and its front end side is open, while its rear end side has a core pipe locking part that is removably fitted into the protruding annular wall 4. It is sealed with a rear end cap 5.

The fitting between the rear end cap 5 and the protruding annular wall 4 can be achieved by, for example, cutting a cut groove 4a on the inner periphery of the protruding annular wall 4, and inserting a protrusion 5a that engages with the cut groove 4a into the rear end cap 5. It is formed so as to protrude from the outer periphery of the core pipe so that it can be rotated and detached when re-coring or refilling the core pipe, which will be described later.

Note that the rear end cap 5 may have any structure as long as it is removably shaped and can restrict the movement of the core pipe in the backward direction, which will be described later, when the cap is fitted.

Further, near the tip of the inner wall of the outer cylinder 1, a long hole 6 for locking the cap is bored to a predetermined length, and an inner wall locking portion of the outer cylinder 1 is provided inside the outer cylinder 1. The core feeding section 3
is housed so that it can slide in the axial direction.

The lead feeding section 3 includes an inner cylinder 9 having a cap retaining step 9a and a fixed cylinder engaging step 9b near the tip, a tip 10 fitted to the tip of the inner cylinder 9, and a tip 10 fitted to the tip of the inner cylinder 9. A core pipe 11 is slidably housed inside the core pipe 9.

The core pipe 11 has its rear end protruding from the inner cylinder 9 in contact with the rear end cap 5 or has a small gap between the core pipe 11 and the rear end cap 5 to restrict its movement in the rear end direction. , a core feeding mechanism 12 is attached to the tip thereof.

As shown in FIGS. 1 and 2, the lead feeding mechanism 12 includes a lead chuck fitted onto the lead pipe 11, and a chuck tightening tube 1 fitted onto the head of the lead chuck 13.
A sleeve 15 that contacts the rear end of the chuck clamping tube 4 and restricts movement of the chuck fastening tube 14 in the backward direction, and an elastic body 16 that is elastically attached between the sleeve 15 and the core pipe 11.

The cap 2 for protecting the core has a cylindrical cap body 17 having approximately the same diameter as the outer tube 1, and a fitting tube 18 fitted inside the cap body 17, and the outer circumference of the fitting tube 18. A protrusion 19 that engages with the length "JL6" of the outer tube 1 when the cap is attached is provided inside the fitting tube 18, and a cap {L20 for accommodating the tip of the lead feeding section 3 is provided inside the fitting tube 18.

Next, the operation of this invention will be explained.

As shown in FIG. 2, when the cap 2 is fitted into the outer cylinder 1 at the end of writing, the tip of the fitting cylinder 18 of the cap 2 is inserted into the outer cylinder 1.
The cap is engaged with the stepped portion 9a of the fitting tube 1.
The protrusion 19 of 8 is locked into the elongated hole 6 of the outer cylinder 1.

Therefore, if the tip of the cap 2 is pressed to the open tip of the outer tube 1, the entire inner tube 9 will move backward because the core pipe 11 is prevented from moving in the backward direction by the rear end cap 5. .

Therefore, this operation has the same result as a knocking operation, and the cap 2 is automatically moved to the position shown in the second figure by the elastic force of the elastic body 16 of the lead feeding mechanism 12.

That is, the lead 21 is always protruded from the tip 10 by the writing amount of dimension A - dimension B (knocking amount) and dimension C shown in the second diagram.

Therefore, as shown in the first diagram, the lead 21 is always in a writing state by simply removing the cap 2 from the outer cylinder 1 at the next writing time.

As described above, according to the writing instrument of this invention, just by closing the cap to protect the lead when you finish writing, the lead is held protruding by the amount of writing, so you can immediately write by removing the cap the next time you write. This has extremely excellent practical effects, such as making it possible.

In this embodiment, a mechanical pencil has been described, but the present invention is not limited to this, and any knock-type writing instrument may be used.

[Brief explanation of the drawing]

FIGS. 1 and 2 show longitudinal sectional views of an embodiment of this invention. 1...Outer tube, 2...Cap for core protection, 8...Fixed tube, 10...Inner tube, 1
2... Core pipe, 13... Core feeding mechanism.

Claims (1)

[Scope of utility model registration request] an inner cylinder 10 that is slidably housed in the outer cylinder 1 in the axial direction;
A core pipe 11 housed in the inner tube 10 and having its rear end fixed to the outer tube 1, a core feeding mechanism 13 provided at the tip of the core pipe 11, and a tip of the outer tube 1. A cap 2 for protecting the lead which is removably fitted into the inner cylinder 10 and presses against the inner cylinder 10 is provided, and by attaching the cap 2 to the outer cylinder 1, it is possible to protrude and hold the necessary amount of lead for writing. A writing instrument.