JPS593909Y2 - knock type mechanical pencil - Google Patents

Description

[Detailed explanation of the invention] This invention is a knock-type mechanical pencil, more specifically,
A double-chuck mechanical pencil has a first chuck for pushing out the lead core inside the main body, and a second chuck for gripping the lead lead on the tip member attached to the front of the main body. This results in a structure that allows for easy and reliable release.

Conventionally, the second chuck at the tip of the above-mentioned knock-type mechanical pencil with two chucks was installed so that it always protruded from the tip of the barrel, and when the lead lead to be gripped was long, the mechanical pencil with the two chucks was A structure is shown which performs the same function as a lead detent member and functions as a lead gripping chuck when the lead becomes too short to be gripped by the first chuck.

By providing a knock-type mechanical pencil with this structure, the length of the lead lead that can be written on has been increased compared to a normal knock-type mechanical pencil, making it possible to shorten the length of the lead lead that would otherwise be wasted without being able to write. However, the second chuck expands slightly only when the lead core is pushed out, loosens its grip on the lead core, and always grips the lead core when the lead core is retracted. If the lead core is pulled out too long, it is difficult to return the lead core to the appropriate length, and if the lead core becomes too short to be gripped by the first chuck, and the next lead core runs out, the lead core It also had problems such as the difficulty of eliminating.

Therefore, the present invention has been developed so that the first chuck advances to the rear part where the lead core is released and presses the rear end of the second chuck, thereby increasing the distance the first chuck moves forward. The aim is to solve the conventional problems by setting .

Hereinafter, the present invention will be described in more detail according to an embodiment shown in the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a main body, and a tip member 3 having internal stepped portions 3a and 3b is screwed onto the tip of the main body by a threaded portion 2.

Reference numeral 4 designates a first chuck for extruding a lead core having a well-known structure in which a tapered part is provided on the head part and a tightening ring 5 is fitted onto the tapered part so as to be able to be locked therein.

The first chuck 4 is fixed to the front part of the core tank 6,
The lead tank 6 is disposed inside the main body 1 with the rear part protruding from the rear end opening of the main body 1, and by pressing the rear end of the lead tank 6 and moving it forward, a second lead gripper, which will be described later, is installed. The forward distance of the first chuck 4 is set so as to press the rear end surface of the chuck 8.

Reference numeral 7 denotes a first spring, which includes a stepped portion 1' provided inside the main body 1 and a locking portion 6 provided on the outer peripheral surface of the core tank 6.
', so as to always repel the core tank 6 toward the rear of the shaft cylinder.

Reference numeral 8 denotes a second chuck having a flange 9 at its rear, which is interposed between the flange 9 and the stepped portion 3a provided inside the tip member 3 described above.

The second chuck 8 is always resiliently pushed backward by the second spring 10, and is locked by the front portion 3C of the tip member 3 when the second chuck 8 grips the lead core.

Next, to describe the operation, in the state of writing (see FIG. 1), the first chuck 4 and the second chuck 8 are moved by the first spring 7 and the second spring 10, respectively. It was repelled backwards and gripped the lead core.

In addition, when pushing out the lead core, press the rear end of the lead tank 6 and move the first chuck 4 forward. The first chuck 4 works together with the tightening ring 5 to push out the lead core. Move forward while holding it.

At that time, the second chuck 8 moves slightly forward against the elastic force of the second spring 10 due to friction with the lead core it is holding, and at the same time expands slightly, causing the lead core to spread. It passes through the lead core while maintaining a moderate amount of friction.

Next, the first chuck 4 moves forward and the tightening ring 5 comes into contact with the stepped portion 3b, so that the engagement between the tightening ring 5 and the first chuck is released, the first chuck 4 expands, and the lead core is removed. Release the grip.

At the same time, the second chuck 8 is connected to the second spring 10.
Because it is repelled backward by the repulsive force, it grips the lead core again.

In this state, when the pressure on the lead tank 6 is released, the first chuck 4 engages with the tightening ring 5 again, grips the lead, completes pushing out a certain amount of lead, and returns to the writing state.

While the first chuck 4 is operating in this manner, the second chuck 8 functions as a detent for the lead lead of a conventional knock-type mechanical pencil.

Next, when the first and second chucks release their grips on the lead core, the first chuck 4 is moved forward by continuing to press the lead tank 6 from the state in which it releases its grip on the lead core. Then, as shown in FIG. Release the grip on the lead core.

At this time, the second chuck 8 performs the original chuck function of gripping and releasing the lead core.

According to the present invention, when the lead core is long enough to be gripped by both the first chuck and the second chuck, extrusion of the lead core, gripping of the lead core, etc. are the same as in the conventional method. This has the effect of After tightening, the lead core can be returned by pushing the tip of the lead core, so the protruding length of the lead core can be adjusted and breakage of the lead core can be prevented.

In addition, if the lead lead is held only by the second chuck, if the distance between the tip of the tip member and the writing surface is set appropriately, the first chuck is further advanced than described above, and the second chuck is expanded. Even if there is no pressure on the new lead, the lead will fall due to its own weight, contact the writing surface, and a length of lead corresponding to the distance between the tip member and the writing surface will protrude, and in this state, the lead tank will not be pressed. Once unraveled, the core is gripped by the second chuck.

Therefore, as long as the lead is long enough to be held by the second chuck, writing is possible, and the length of the lead that can be written on is further increased than in the past.

Furthermore, if you perform this operation with a sufficient distance between the tip of the tip and the writing surface, you can easily remove the lead, and if you perform this operation with the tip of the tip pointing upward, you will be able to remove the lead that can be ejected. can be stored in the wick tank with one-handed operation.

Various practical effects such as these can be achieved.

Incidentally, when the second chuck 8 does not grip the lead core, the second chuck 8 is protected by storing it in the tip member 3 as shown in FIG. You can also tighten it.

This is achieved by widening the split width of the second chuck 8 and making the outer diameter of the head smaller than the inner diameter of the tip when the chuck is closed without gripping the lead core. .

In addition, a taper part that narrows toward the rear may be provided at the front part of the tip member, and the second chuck head may be engaged with the taper part, or a known method having a pressing part on the side surface of the main body may be used. The structure of the present invention can also be used for a knock-type mechanical pencil.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a state in which the first chuck and the second chuck of the embodiment of the present invention grip a lead core, and FIG. 2 is a sectional view showing the state in which the first chuck and the second chuck of the embodiment of the present invention grip FIG. 3 is a sectional view showing a state in which the second chuck is housed in the tip. FIG. 1...Main body, 3...Tip member, 4...
...First chuck, 5...Tightening ring, 7.
...First spring, 8...Second chuck, 10...Second spring, L...
...Lead core.

Claims (1)

[Scope of utility model registration request] A first chuck for extruding a lead core, which is always repelled backward by a spring, is disposed in the main body to which a tip member is attached at the front. In a knock-type mechanical pencil in which a second chuck for gripping the lead core is inserted, the first chuck moves forward and the second chuck moves forward to release the lead lead. A knock-type mechanical pencil characterized in that the forward distance of the first chuck is set so that the second chuck can be expanded by pressing the rear end.