JPH077198Y2 - Mechanical pencil with variable centering mechanism - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] In the present invention, the writing lead is extended by a knocking operation. When adjusting the length of the writing lead, the adjusting crown is rotated with respect to the outer cylinder. By moving the junction in the axial direction, the axial movement distance of the chuck and chuck ring is adjusted, and the lead-out length of the chuck and chuck ring determined by this distance is adjusted. The present invention relates to a mechanical pencil capable of feeding a lead by an adjusted length suitable for writing by a user.

[Conventional technology and its problems]

As a conventional example of this type, there is a mechanical pencil described in Japanese Utility Model Publication No. 62-34795 (first conventional example), Japanese Utility Model Publication 1-29117 (second conventional example) and the like.

In the first conventional example, a chuck is connected to the tip of a movable core case housed in a barrel, and a tightening ring is put on the tip of the chuck so that a writing core can be pushed out between the barrel and the movable core case. A retraction spring is interposed, and a rotating cylinder is screwed onto the outer circumference of the shaft cylinder so as to be movable in the axial direction, and a variable distance is provided between the outer surface of the front part of the shaft cylinder and the inner surface of the front part of the rotating cylinder. A step in which the base of the tip is screwed into the tip of the moving cylinder, an inner hole is formed in the tip, the chuck and the tightening ring are axially movably fitted, and the tightening ring is locked in the inner hole. The axial movement distance of the tightening ring that changes in association with the variable distance is provided between the step and the tip of the chuck and the end of the tightening ring.

The second conventional example is a chuck in which a sliding body having an elastic member for holding a core arranged in the front portion is urged rearward by an elastic member to be arranged in the barrel and a core storage tube is arranged in the rear portion. Is urged rearward by an elastic member to be placed in the slide body so as to abut a chuck seat provided in the shaft cylinder, and the push crown and the core storage tube movably attached to the rear portion of the slide body. It is arranged at a predetermined interval.

In both the first and second conventional examples, by adjusting the variable distance, it is possible to freely adjust the feeding length of the writing core within the movement limit of the variable distance, and therefore, the writing length can be adjusted to suit the user. However, there is an effect that it is possible to minimize the risk of core breakage and that it is not necessary to perform frequent core feeding operations, but in any case, there is a problem that the structure is complicated and high accuracy of parts is required, and it cannot be implemented at low cost. .

[Means for Solving the Problems]

The mechanical pencil of the present invention solves the above problems.
As shown in the first and third illustrations, a chuck 3 is connected to a lead case 2 housed in an outer cylinder 1, a chuck ring 4 is fitted to the chuck 3, and a junction 5 and a lead case that abut on the chuck ring 4 are attached. 2 and the chuck tightening elastic body 6
Is provided, and a step portion 8 with which the chuck ring 4 is locked is provided in the tip 7 of the outer cylinder 1. The junction 5 is locked to the outer cylinder 1 in the rotational direction and movably coupled in the axial direction. The adjustment tail crown 9 is provided so as to move in the axial direction.

[Action]

When the adjusting crown 9 is rotated, the junction 5 provided to move the junction 5 in the axial direction is moved forward or backward depending on the rotation direction thereof.
As a result, the chuck 3 and the chuck ring 4 are moved in the forward direction or the backward direction, and the distance 1 (variable distance) between the front end surface of the chuck 3 and the chuck ring 4 is adjusted in accordance with the rotation amount of the adjustment crown 9. To be done.

When the variable distance 1 is long, when the lead case 2 is moved forward, both the chuck 3 and the chuck ring 4 are moved forward, and after the chuck ring 4 contacts the step portion 8, the lead 15 is stuck until then. The chuck 3 that has been moved forward escapes from the chuck ring 4, and the chuck 3 is opened to release the core 15 that has been stuck. Then, the elastic force of the chuck tightening elastic body 6 causes the chuck 3 to retreat and fit into the chuck ring 4 to stick the lead 15, and the lead 15 is extended from the tip of the tip 7 by repeating the above operation. But
The lead-out length increases according to the axial movement distance of the chuck 3 and the chuck ring 4, that is, the variable distance l.

Further, when the variable distance l is short, the lead-out length is shortened according to the axial movement distance of the chuck 3 and the chuck ring 4, that is, the length of the variable distance l. Thus, the payout length of the core 15 can be adjusted by adjusting the variable distance l.

〔Example〕

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

FIG. 1 is a sectional view showing the construction of a first embodiment of a mechanical pencil of the present invention. Reference numeral 1 is an outer cylinder, 2 is a lead case housed in the outer barrel 1, and 3 is a chuck connected to the lead case 2. is there. A chuck ring 4 is fitted on the chuck 3,
A chuck tightening spring 6 is inserted between the inner front end of the junction 5 abutting the chuck ring 4 and the front part of the lead case 2.

A tip 7 is screwed to the tip of the outer cylinder 1, and a step 8 for locking the chuck ring 4 is provided in the tip 7.
A junction 5 is locked in the outer cylinder 1 in the rotation direction and is connected so as to be movable in the axial direction.

To connect the outer cylinder 1 and the junction 5, for example, an axial key groove 11 is provided on the inner surface of the outer cylinder 1, and a key 10 that fits into the key groove 11 is provided on the rear outer surface of the sleeve 5a of the junction 5 to form the outer cylinder 1. In addition, the junction 5 is locked in the rotation direction and is coupled so as to be movable in the axial direction. An annular adjusting tail cap 9 is provided so as to face the rear surface of the outer cylinder 1, and its sleeve 9a is provided.
Is inserted in the outer cylinder 1. An inner periphery of the rear portion of the sleeve 5a of the junction 5 and an outer periphery of the front portion of the sleeve 9a of the adjusting crown 9 are screwed together by an adjusting screw 16.

A spring 13 is provided between the rear surface of the sleeve 5a of the junction 5 and the front surface of the annular tail plug 17 fixed to the inner periphery of the rear portion of the outer cylinder 1.
Is provided. This spring 13 prevents the adjusting tail plug 9 from naturally rotating during writing to prevent the junction 5 from moving in the axial direction, and also serves to prevent the screw portion from loosening. The annular tail plug 17 may be formed integrally with the outer cylinder 1. A tail crown stopper 18 that comes into contact with the outer cylinder 1 or the annular tail plug 17 and prevents the rearward movement of the adjusting tail crown 9 is attached to a fitting groove provided on the outer periphery of the adjusting tail crown 9.

Reference numeral 19 is a tip pipe fixed to the tip of the tip 7, and 20 is a lead holding portion, which is a tip pipe protruding and retracting from the tip of the tip 7.
A slider having 19 and the core holding portion 20 may be used.

Reference numeral 21 is a connecting pipe fixed to the rear portion of the core case 2, 22 is an eraser jacket detachably attached to the connecting pipe 21, 23 is an eraser, and 24 is a knock cap.

When the knock cap 24 is knocked, the lead case 2, the chuck 3 and the chuck ring 4 move forward against the spring force of the chuck tightening spring 6, and after the chuck ring 4 comes into contact with the step portion 8, the chuck 3 further moves forward. Then, the chuck 3 is released from the inside of the chuck ring 4 and opened, and then the chuck 3 is retracted by the spring force of the chuck tightening spring 6 and fitted into the chuck ring 4 to stick the lead 15, and the above-described operation is repeated.
15 is a chuck 3 and a chuck ring 4 from the tip of the tip 7
The length l is extended in accordance with the axial movement distance l of.

When adjusting (changing) the feeding length l of the core 15, first
In the figure, when the adjusting crown 9 is rotated clockwise, for example,
Junction 5 screwed to this with adjusting screw 16
Is a distance corresponding to the rotation amount, for example, a distance (see FIG. 2 (a)) in which the rear end of the tip 7 and the front end of the sleeve 5a of the junction 5 are in contact with each other and the screwing amount of the adjusting screw 16 is minimum (see FIG. 2 (a)) Thus, if the distance between the front ends of the chuck 3 and the chuck ring 4 and the step portion 8, that is, the axial movement distance l ₁ of the chuck 3 and the chuck ring 4 is set to, for example, 0.3 mm, the core 15 is knocked by the knocking operation. Each l ₁ = 0.3 mm is fed from the tip pipe 19 of the tip tool 7 (see FIG. 2 (a)).

Further, when the adjusting crown 9 is rotated counterclockwise in FIG. 1, the junction 5 screwed to the adjusting crown 9 by the adjusting screw 16 has a distance corresponding to the rotation amount, for example, the screwing amount of the adjusting screw 16 becomes maximum. By a distance (see FIG. 2 (b)), the distance between the front ends of the chuck 3 and the chuck ring 4 and the step portion 8, that is, the axial movement distance l ₂ of the chuck 3 and the chuck ring 4 is, for example, If it is 1.0 mm, the core 15 is fed out from the tip pipe 19 of the tip 7 by l ₂ = 1.0 mm by the knocking operation.

Therefore, the lead-out length in this embodiment can be continuously varied from l ₁ = 0.3 mm to l ₂ = 1.0 mm by rotating the adjusting crown 9.

FIG. 3 is a sectional view showing the construction of the second embodiment of the mechanical pencil of the present invention. In this second embodiment, the key groove 11 is provided in the sleeve 5a of the junction 5 and the outer cylinder 1 is passed through the key groove 11. The key 10 is inserted, and the same operational effect as that of the first embodiment is obtained. Reference numeral 12 is a receiving portion provided at the end of the sleeve 5a of the junction 5.

Also, even if the outer cylinder 1 and the junction 5 are connected by a polygonal portion that fits with each other, the same effect can be obtained.

FIG. 4 shows the sleeve 5a of the junction 5 in FIG.
This is an example in which the adjusting screw portion 16a with the key 10 and the adjusting screw portion 16a with the key 10 are separately provided, and the connecting portion of the adjusting screw portion 16a with the key 10 is press-fitted or screwed into the rear portion of the sleeve 5a.

FIG. 5 shows the sleeve 5a of the junction 5 in FIG.
FIG. 4 is an example in which the connecting portion of the adjusting screw portion 16b with the receiving portion 12 is integrally connected to the rear portion of the sleeve 5a by press fitting or screwing, and the adjusting screw portion 16b with the receiving portion 12 are formed separately, and FIG. Also, it is apparent that the configuration shown in FIG.

6 (a) and 6 (b) are sectional views showing the structure of the third embodiment. In this third embodiment, the tail crown stopper 18 is attached to the fitting groove provided on the outer periphery of the adjusting tail crown 9. A cushion allowance a is provided between the tail cap stopper 18 and the step portion 18a of the annular tail plug 17.
Is provided. Other configurations are exactly the same as in FIG.

By rotating the adjusting crown 9 in the third embodiment, the core 15 moves from the tip pipe 19 of the tip 7 to the axial movement distance l of the chuck 3 and the chuck ring 4 as in the case of the first embodiment shown in FIG. It is possible to pay out the length l according to.
In the case of FIG. 6 (a), the payout length of the core 15 is l ₁ , and in the case of FIG. 6 (b), the payout length of the core 15 is l ₂ .

When writing pressure is applied to the core 15 in a state where the core 15 projects from the tip pipe 19 of the tip tool 7 as shown in FIG. 7 (a), as shown in FIG. 7 (b) within the range of the cushion allowance a. Spring 13
The core 15 is retracted against the force and prevents breakage of the core 15. In particular, as shown in FIG. 2 (b), when the amount of protrusion of the core 15 is large, the proportion of breakage due to the writing pressure increases, but in the third embodiment, since the cushioning action is performed, the degree of breakage is extremely small. is there.

FIG. 8 shows that when the adjustment tail crown 9 is further rotated after the junction 5 comes into contact with the rear end of the tip 7 in FIG. 6 (a), the rear end of the outer cylinder 1 and the adjustment tail crown 9 are connected as shown in FIG. Gap a between
However, if an arrow is provided on the outer surface of the outer cylinder 1 and the adjustment crown 9 has a minimum value l ₁ = 0.3 mm and a maximum value l ₂ = 1.0 mm, the operation of creating such a gap a can be prevented. It can be avoided.

In the present invention, the lead-out length or the hardness of the lead to be used may be displayed.

[Effect of device]

As described above, according to the present invention, the chuck 3 is connected to the lead case 2 housed in the outer cylinder 1, the chuck ring 4 is fitted to the chuck 3, and the junction 5 and the lead that come into contact with the chuck ring 4 and the lead are attached. A chuck tightening elastic body 6 is inserted between the case 2 and a case 8, and a step portion 8 to which the chuck ring 4 is locked is provided in a tip 7 of the outer cylinder 1, and a junction 5 is locked to the outer cylinder 1 in a rotational direction. Connected so that it can move in the axial direction,
Since the adjusting tail crown 9 is provided to move the junction 5 in the axial direction, the core feeding length l can be freely adjusted within the movement limits l _{1 to} l ₂ of the variable distance by rotating the adjusting tail crown 9. Therefore, it is possible to write with a pay-out length suitable for oneself, the risk of core breakage can be minimized, and there is no need to perform frequent core pay-out operations, of course, compared to the conventional mechanical pencil of this type. Thus, the mechanical pencil can be greatly simplified, the precision of parts can be reduced, and a mechanical pencil that can be implemented at low cost can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing the structure of a mechanical pencil according to a first embodiment of the present invention, and FIGS. Is the second mechanical pencil of the present invention
FIG. 4 is a cross-sectional view showing the structure of the embodiment, FIG. 4 is a cross-sectional view of an essential part when the junction and the adjustment screw part with a key are separately implemented in FIG. 1, and FIG. 5 is the junction and the receiving part in FIG. FIG. 6 (a) and FIG. 6 (b) are cross-sectional views of a main part when the attached adjusting screw portion is implemented separately, and FIGS. 8) is a sectional view for explaining the operation in the third embodiment, and FIG. 8 is a sectional view for explaining another operation state in the third embodiment shown in FIG. 6 (a). 1 ... Outer cylinder, 2 ... Core case, 3 ... Chuck, 4 ...
Chuck ring, 5 ... Junction, 5a ... Sleeve, 6 ... Chuck tightening elastic body (spring), 7 ... Tip, 8 ... Step, 9 ... Adjusting crown, 9a ... Sleeve, 10
...... Key, 11 ...... Key groove, 12 ...... Reception part, 13 ...... Elastic body (spring).

Claims (7)

[Scope of utility model registration request] 1. A chuck (3) is connected to a lead case (2) housed in an outer cylinder (1), and a chuck ring (4) is fitted on the chuck (3). The chuck tightening elastic body (6) is inserted between the junction (5) and the core case (2) that come into contact with the chuck ring, and the chuck ring (4) is locked in the tip tool (7) of the outer cylinder (1). A step (8) is provided, the junction (5) is locked to the outer cylinder (1) in the rotation direction and is movably connected in the axial direction, and the adjustment crown (9) is arranged to move the junction (5) in the axial direction. ) Is provided, a mechanical pencil with a variable centering mechanism. 2. The centering variable mechanism according to claim 1, wherein the outer cylinder (1) and the junction (5) can be moved back and forth by means of the key (10) and the key groove (11) and cannot be rotated. mechanical pencil. 3. A key (1) which is provided with a key groove (11) in the junction (5) and which penetrates the outer cylinder (1) in the key groove (11).
A mechanical pencil with a variable centering mechanism according to claim 1, wherein the mechanical pencil is inserted. 4. A mechanical pencil with a centering variable mechanism according to claim 1, wherein the outer cylinder (1) and the junction (5) are connected by a polygonal portion that fits with each other. 5. An elastic body (13) is provided between the outer cylinder (1) or the annular tail plug (17) and the junction (5), according to any one of claims 1 to 4. Mechanical pencil with variable centering mechanism. 6. A tail cap stopper (18) for contacting the outer cylinder (1) or the annular tail plug (17) to prevent rearward movement of the tail cap (9) is provided on the outer circumference of the tail cap (9). A mechanical pencil with a variable centering mechanism according to any one of claims 1 to 5, which is attached to a mechanical pencil. 7. A tail cap stopper (18) is attached to the outer periphery of the adjusting tail cap (9), and the tail cap stopper (18) and the step portion (18a) of the outer cylinder (1) or annular tail plug (17). 6. A mechanical pencil with a centering variable mechanism according to claim 5, wherein a cushioning margin a is provided between said and the center.