JPH0413199Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

This invention relates to a sharp pencil that dramatically improves assembly efficiency and has measures to prevent the core pipe from rotating and from rattling.

[Conventional technology]

Recently, for the purpose of simplifying the manufacturing process and assembly work, a sharp pencil has been developed in which a stepped part or an engaging hole is provided in the inner wall of the outer cylinder, and a part of the lead delivery mechanism is locked therein.

[Problem that the idea aims to solve]

However, with conventional sharpening pencils, when inserting the stopper into the locking hole of the outer cylinder, a fine tubular jig was required to cover the core pipe and press the stopper, which resulted in poor assembly efficiency. . In addition, conventional sharp pencils do not have measures to prevent the lead pipe from rotating or wobbling, so if you turn the rear end of the lead pipe by hand, the lead stuck to the lead chuck and the lead will be inserted. There were problems such as the tip pipe rotating together, which bothered the user, and also making it difficult to use due to looseness when writing. This idea was made to solve the above-mentioned problems, and it is possible to unite the core pipe with the lead feeding mechanism attached to the tip and the tip tool into one block, which improves assembly efficiency. An object of the present invention is to provide a sharpening pencil capable of preventing rotation of a core pipe and preventing rattling.

[Means to solve the problem]

The sharp pencil according to this invention has a core pipe that is inserted and set into an outer cylinder so that it can be clicked, and a washer that is movable in the axial direction and biased forward, and is attached to the tip of the core pipe. It includes a lead feeding mechanism and a tip into which the lead feeding mechanism is inserted so as to be movable in the axial direction, the tip is provided with a washer locking portion, and the core pipe and the tip are slidable in the axial direction. A locking engaging portion is provided which is movable and engages in the axial direction, and the locking engaging portions are fitted into and engaged with each other, and the washer is locked and fixed to the washer locking portion. The core pipe having a lead delivery mechanism and the tip tool are integrated into one block, and the block is inserted into the outer cylinder from the tip side to removably connect and fix the tip tool to the outer cylinder. It is something.

[Effect]

In the sharp pencil according to this invention, the tip side of the lead pipe is inserted into the tip together with the lead delivery mechanism, and at the time of insertion, the locking engagement portions of the lead pipe and the tip are fitted and engaged so as to be movable in the axial direction. At the same time, by locking and fixing the washer provided in the lead delivery mechanism to the washer locking portion of the tip tool, the core pipe provided with the lead delivery mechanism and the tip tool are integrated into one block. Therefore, the sharpening pencil can be assembled by simply inserting this block into the outer cylinder and removably connecting and fixing the tip to the outer cylinder, thereby improving the efficiency of the assembly process. In addition, in its assembled state, as mentioned above,
The anti-rotation engaging portions of the tip and the core pipe engage,
In addition, since the washer on the lead delivery mechanism side is locked and fixed to the washer locking portion on the tip end side, the core pipe does not rotate unnecessarily, and
Shaking is also reliably prevented, making the sharp pencil easier to use and improving its performance.

【Example】

An embodiment of this invention will be described below with reference to the drawings. In FIG. 1, a tip 2, a lead delivery mechanism 3, and a lead pipe 4 are inserted into an outer cylinder 1. As shown in FIGS. 1 and 2, the cylindrical wall portion of the tip 2 has a long groove 5 extending in the axial direction as a rotation preventing engagement portion for the core pipe 4, and a distal end side of the long groove 5. A washer locking portion 7 formed continuously is provided. The washer locking portion 7 has the illustrated configuration of a tapered protrusion formed protruding from the distal end side of the long groove 5 in a direction that narrows the width of the long groove 5. Furthermore, a tip pipe 9 for protecting the core 8 and a rubber gasket 10 for applying a predetermined frictional force to the core 8 are provided at the tip of the tip 2. On the other hand, on the outer periphery of the tip side of the core pipe 4, a detent projection 4a is integrally formed as a detent engagement portion that is slidable in the axial direction with respect to the long groove 5 and engaged in the axial direction. There is. Further, a core delivery mechanism 3 is attached to the tip of the core pipe 4. This lead delivery mechanism 3 includes a lead chuck 11 for inserting a core that is fitted and connected to the tip of a core pipe 4, and a chuck tightening ring 12 that is loosely fitted to the head of the lead chuck 11 and tightens the lead chuck.
A washer 6 that comes into contact with the rear end of the chuck tightening ring 12 and also functions as a sleeve, and an elastic body 13 for chuck tightening that is attached between the washer 6 and the tip of the core pipe 4. It has a well-equipped structure. The washer 6 integrally has a washer protrusion 6a for engaging with the washer locking portion 7. Here, the distance between the tip of core pipe 4 and washers 6
L ₁ , the length of the elastic body 13 that is compressed and in close contact with the elastic body 13 during knocking (elastic body contact distance X), and the length that the tip of the lead chuck 11 moves forward during knocking L ₂ (knocking distance) Between L ₂ > L ₁ −X
There is a relationship between As a result, when the lead delivery mechanism 3 is inserted into the tip 2 and the core pipe 4 is knocked, the elastic body 13 is pushed by the tip of the core pipe 4 until it comes into close contact with the elastic body 13, and when pushed further, the washer protrusion The washer protrusion 6a moves forward by pushing apart the tapered washer locking part 7, and passes forward through the washer locking part 7, at which point the washer protrusion 6a is securely locked and fixed to the washer locking part 7. be done. At this time, since the rear side of the tapered part of the washer locking part 7 is gently sloped in such a way that it gradually becomes narrower toward the distal end, the washer protrusion 6a smoothly pushes the washer locking part 7. The front side of the washer locking part 7 can be moved forward while spreading.
Since the washer protrusion 6a is sharply inclined in a manner that gradually narrows toward the rear, the washer protrusion 6a is locked and fixed at an appropriate location on the tapered washer locking portion 7, thereby preventing wobbling. . In order to more reliably spread the washer locking portion 7, a slit 14 may be formed in the tip 2, as shown by the imaginary line in the second figure. Next, the assembly of the sharpening pencil will be explained. First, the core feeding mechanism 3 attached to the tip of the core pipe 4 is inserted into the tip 2 from the rear end side of the tip 2, and then the core pipe 4 is clicked, and the core pipe 4 is attached to the elastic body 13. It moves forward against the force, and at the same time, the elastic body 13 is pushed until it comes into close contact, and finally comes into close contact. Then, the washer 6 is brought into contact and moved by the elastic force of the elastic body 13 in close contact with the washer 6, and the washer 6 is forced to spread and pass through the tapered washer locking portion 7, so that the jig, etc. is completely removed. The washer protrusion 6a can be locked and fixed to the tapered washer locking portion 7 without the need. Through the above steps, the core pipe 4 equipped with the core delivery mechanism 3 and the tip 2 are integrated into one block as shown in the second figure. Therefore, one block consisting of the core pipe 4 and tip tool 2 that have been made into a unit is inserted by inserting the rear end side into the outer cylinder 1 as shown in the first figure, and the tip end side of the tip tool 2 is inserted. The assembly of the sharp pencil is completed by removably connecting and fixing the outer cylinder 1 to the inner wall on the distal end side using a fixing means 2a such as screwing. 4 and 5 show other embodiments of the rotation prevention means for the tip tool 2 and the core pipe 4. In this embodiment, the inner circumferential wall surface on the rear end side of the tip tool 2 and the tip of the core pipe 4 are shown. The side outer peripheral surface part has a polygonal shape (6 in this example).
The polygonal portions are fitted into and engaged with each other so as to be movable in the axial direction, and in this case as well, the same anti-rotation effect as in the previous embodiment is achieved.

[Effect of the idea]

As described above, according to this invention, a washer locking portion is provided in the tip for inserting the core delivery mechanism attached to the tip of the core pipe so as to be movable in the axial direction together with the tip of the core pipe, and and the tip tool is provided with a detent engaging portion which is slidable in the axial direction and engages in the axial direction, and the detent engaging portions are fitted into and engaged with each other, and the washer is connected to the washer. The core pipe having the lead feeding mechanism and the tip tool are locked and fixed to the locking part to form a unit, and the block is inserted into the outer cylinder from the tip side to close the outer cylinder. Since the structure is such that the tip is removably connected and fixed, the tip can be attached to and detached from the outer cylinder by inserting one block in which the core pipe and the tip are integrated into the outer cylinder. The sharpening pencil can be assembled easily and skillfully by simply connecting and fixing it, and the efficiency of the assembly work can be improved. In addition, in the assembled state, as described above, the rotation-preventing engaging parts of the tip tool and the core pipe are engaged with each other, and the washer on the lead delivery mechanism side is locked and fixed to the washer locking part on the tip tool side. This prevents the core pipe from rotating uncontrollably, and
This has the effect of reliably preventing rattling, making the sharp pencil easier to use, and improving its performance.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of a mechanical pencil according to an embodiment of this invention, Fig. 2 is a plan view showing a state in which the tip and core pipe of the same mechanical pencil are integrated into a unit, and Fig. 3 is a view of the mechanical pencil shown in Fig. 2. 4 is a longitudinal sectional view of a main part showing another embodiment, and FIG. 5 is a sectional view taken along line BB in FIG. 4. 1... Outer cylinder, 2... Tip tool, 3... Lead delivery mechanism,
4... Core pipe, 4a... Anti-rotation protrusion (preventing engagement part), 5... Long groove (preventing engagement part), 6...
... Washer, 7... Washer locking part.

Claims (1)

[Scope of utility model registration request] A core pipe 4 is inserted and set into the outer cylinder 1 so that it can be clicked, and a core delivery mechanism 3 is attached to the tip of the core pipe 4 and has a washer 6 that is movable in the axial direction and biased forward. and a tip 2 into which the lead delivery mechanism 3 is inserted so as to be movable in the axial direction, the tip 2 is provided with a washer locking portion 7, and the core pipe 4 and the tip 2 are provided with a washer locking portion 7. Anti-rotation engaging parts 4a and 5 which are slidable and engage in the axial direction are provided, respectively, and the anti-rotation engaging parts 4a,
5. At the same time as fitting and engaging each other, the washer 6 is locked and fixed to the washer locking portion 7, and the core pipe 4 having the core delivery mechanism 3 and the tip tool 2 are unitized into one block. A sharp pencil characterized in that the block is inserted into the outer cylinder 1 from the tip 2 side and the tip 2 is removably connected and fixed to the outer cylinder 1.