JPH0732128Y2 - mechanical pencil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mechanical pencil for supplying a lead core by using a piezoelectric actuator.

(Prior art and its problems) As a drawing head of an automatic drafting machine, one using a mechanical pencil structure is used. For example, a ball chuck mechanism capable of allowing the lead core to move forward but preventing the lead core from moving backward by a wedge action is fixed in the holder, and a slider spring is urged forward of the ball chuck mechanism in front of the ball chuck mechanism. A slider that is slidable is placed in the front part of the holder, and after writing, the front end surface of the slider is separated from the paper surface so that the lead detent member in the slider that returns can be pulled out while holding the lead core. Is commonly used. However, even though the lead core already gripped by the ball chuck mechanism can be sequentially rolled forward, in order to supply a new core such as the second one, for example, a normal rear end knock type mechanical pencil is used. As described above, it has been considered to mount a structure for mechanically performing the knocking operation from the rear on the automatic drafting machine, but it has a drawback that it is structurally complicated.

(Means for Solving the Problem) The present invention is such that when voltage is applied, strain or stress (pressure, tension, etc.)
The above-mentioned problem is solved by using a piezoelectric actuator using piezoelectric ceramics that causes a certain displacement, and its gist is to allow the lead core to move forward, but to retract it by a wedge action. A mechanical pencil having a ball chuck mechanism for blocking, wherein a piezoelectric actuator for pressing and expanding the chuck member is provided behind a chuck member of the ball chuck mechanism. .

(Operation) As shown in FIG. 5, the piezoelectric ceramic is provided with an electrode I, and when a voltage E is applied, the piezoelectric ceramic extends at a rate of d in a direction parallel to the polarization direction (direction of arrow P) and at the same time, at a rate of d in a right angle. The present invention, which shows the phenomenon of contraction due to the above, utilizes this phenomenon to advance the lead gripping means.

(Embodiment) A detailed description will be given below based on an embodiment shown in the accompanying drawings.

In FIG. 1, reference numeral 1 is a holder, and a tip metal 2 is screwed on the front side. Inside the tip 2 is biased forward by a slider spring 3 interposed between the tip 2 and a ball chuck mechanism to be described later, and a core detent member 4 is slidable inward within the tip 2. A slider 5 is provided. Reference numeral 6 denotes a ball chuck mechanism disposed behind the slider 4 and inside the holder 1. The ball chuck mechanism 6 is divided into a plurality of front portions and is capable of expanding and holding. ), A trochanter 8 mounted on a dish-shaped receiving seat 7a formed on the outer surface of the head of the chuck body 7, and the trochanter 8 can be slidably guided to close the chuck body 7. It comprises a chuck ring 9 having an inclined surface 9a provided on the inner surface thereof, and a chuck spring 10 for biasing the chuck body 7 rearward with respect to the chuck ring 9. Further, in order to obtain a more reliable expansion of the chuck body 7 during forward movement, an end member 11 having an inclined surface 11a on which the inclined surface 7b of the chuck body 7 can ride is provided in front of the chuck body 7. . Note that this structure is not necessary if the chuck body 7 itself has a sufficient self-expanding force. A piezoelectric actuator 12 is arranged at a position opposite to the rear side of the chuck body 7.
A lead wire 13 is drawn from 12 and is connected to an automatic drafting machine (not shown).

Next, the operation will be described.

FIG. 2 is a diagram showing a state in which a voltage is applied, in which the piezoelectric actuator 12 expands and contracts to press the rear end surface of the chuck body 7 and open the head. The lead core falls by its own weight to the rear end of the first core. Next, when the application of voltage is stopped, the piezoelectric actuator 12 returns to the initial state, whereby the chuck member 7 also returns, and the second core is gripped.

FIG. 3 shows another usage of the piezoelectric actuator, which is different from the above embodiment in that one side of the piezoelectric actuator 12 is fixed to the holder 1. Piezoelectric Actuator 12 When fixed in this manner, the piezoelectric actuator 12 causes a phenomenon in which the free end at the front bends when a voltage is applied, and this is utilized in the second embodiment.

FIG. 4 shows another embodiment of the lead core holding means, which differs from the above embodiment in that the ball 14 is used instead of the chuck body 7 to hold the lead core. Place the ball 14 at the front end of the pusher 15, and
A stopper 18 that is constantly urged backward by a spring 16 in front of 14 to press the ball 14 against an inclined surface 17a provided on the inner surface of the cylindrical body 17 and to cause a wedge action between the inclined surface 17a and the lead core. Is provided. This wedge action holds the lead core. In this embodiment, the lead detent member is not necessary because the lead core can always be held lightly.
Moreover, since the ball can be fed out while rotating the lead core, the lead core can be fed out without expanding the chuck head completely like a general chuck,
This is preferable because the displacement of the piezoelectric actuator can be small. A cylinder may be used instead of the ball,
Further, the number of these may be at least two or more.

Although the drawing head of the automatic drafting machine has been described as an example in the above embodiment, the present invention can of course be applied to a general mechanical pencil.

(Effect of the invention) The present invention, when a voltage is applied, causes strain or stress (pressure, tension, etc.).
The above-mentioned problem is solved by using a piezoelectric actuator using piezoelectric ceramics that causes a certain displacement, and its gist is to allow the lead core to move forward, but to retract it by a wedge action. A mechanical pencil having a ball chuck mechanism for blocking, wherein a piezoelectric actuator for pressing and expanding the chuck member is provided behind a chuck member of the ball chuck mechanism. As a result, the chuck member of the ball chuck mechanism can be advanced and expanded, and the second lead core can be reliably dropped into the chuck member.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a sectional view showing an operation, FIGS. 3 and 4 are sectional views showing other embodiments, and FIG. 5 is a piezoelectric actuator. It is a schematic diagram. 7 ... Chuck body (chuck member) 14 ... Ball (chuck member) 12 ... Piezoelectric actuator

Claims (1)

[Scope of utility model registration request] 1. A mechanical pencil having a ball chuck mechanism which allows the lead core to move forward, but prevents the lead core from moving backward by a wedge action, and presses the chuck member behind the chuck member of the ball chuck mechanism. A mechanical pencil with a piezoelectric actuator that expands and spreads.