JP3844417B2 - Composite writing instrument - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a composite writing instrument that accommodates a plurality of writing shafts, and selectively makes these writing shafts project.
[0002]
[Prior art]
Conventionally, as this type of composite writing instrument, for example, the one described in Japanese Utility Model Publication No. 56-15031 is known. Briefly explaining the configuration and operation of the composite writing instrument described in this publication, the composite writing instrument includes a front shaft (lower shaft case), a rear shaft (upper shaft case), a guide sleeve fixed to the front shaft, and having a guide groove. And a plurality of writing shaft bodies having a slider housed in the front shaft and guided in the guide groove, and a curved casing having a slide inclined surface and a notch engaging portion fixed to the rear shaft. By rotating the rear shaft with respect to the front shaft, relative rotation occurs between the curved casing and the guide sleeve, and one of the writing shafts guided by the guide sleeve engages with the notch engaging portion of the curved casing. Thus, it can protrude from the tip opening of the front shaft. Further, when the writing shaft body is a mechanical pencil shaft, by knocking the rear shaft with respect to the front shaft, the knocking operation is transmitted through the curved casing and the slider, so that the lead feeding operation can be performed. It is like that.
[0003]
[Problems to be solved by the invention]
In such a conventional composite writing instrument, the rear end of the rear shaft covers and overlaps the rear end of the front shaft so that the rear shaft can knock with respect to the front shaft. It is necessary to adopt a different structure. However, such an overcap structure has poor operability because the rear shaft that occupies approximately half of the writing instrument moves in the hand holding the writing instrument during the knocking operation.
[0004]
As a structure other than the overcap structure, it is possible to secure a knock margin by providing an axial clearance between the rear shaft and the front shaft. The entire shaft moves, operability is poor, and a gap is formed between the rear shaft and the front shaft. In order to close the gap, a bellows-like rubber member that can be expanded and contracted in the axial direction is also commercially available. However, if such a rubber member is provided, the number of parts and the part cost increase. There is also a problem.
[0005]
Further, as another composite writing instrument, the rear shaft and the front shaft are screwed and coupled so as to be separable without gaps in the axial direction, and in a state where both are coupled, they cannot be rotated relative to each other and cannot be moved in the axial direction. When a knocking part is provided separately from the rear shaft and the knocking part is rotated, one writing shaft body is selectively protruded from a plurality of writing shaft bodies, and the protruding writing shaft body is a mechanical pencil shaft. Also available are those that allow the core to be extended by knocking the knock portion. However, in the case of such a composite writing instrument, since the knock portion is small, there is a problem that it is difficult to perform the rotation operation and the operability is poor.
[0006]
The present invention has been made in view of the problems associated with each of the conventional composite writing instruments, and an object thereof is to provide a composite writing instrument having good operability for both the rotation operation and the knocking operation.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, the front shaft, the rear shaft, and the front shaft and the rear shaft are inserted between the front shaft and the front shaft so as to be separable. The front shaft and the rear shaft can be separated from each other, and the front shaft and the rear shaft can be separated from each other, and the both can be relatively rotated in the connected state and cannot be moved in the axial direction. A connecting middle shaft, a plurality of writing shaft bodies that are housed in the front shaft and are always urged rearward and guided so as to be movable in the axial direction by the middle shaft, and are not rotatable relative to the rear shaft in the rear shaft and axial direction A cam cylinder that is provided so as to be movable, and that is selectively guided in the axial direction by the middle shaft by relative rotation with the front shaft and the middle shaft. And a knock portion protruding from the rear end of the rear shaft, the knock portion of the knock portion Ri sufficiently to allow a knocking of the writing shaft body that protrudes by the cam cylinder by click, the middle axle is into the rear shaft has a cylindrical portion after extending substantially concentrically, the inner peripheral surface of the rear cylinder portion A guide portion for guiding the movement of the writing shaft body in the axial direction is formed .
When the rear shaft is rotated relative to the front shaft, the cam cylinder that cannot rotate relative to the rear shaft rotates together with the rear shaft, and the relative rotation generated between the front shaft and the middle shaft selectively causes the middle shaft to rotate. The one writing shaft guided in the axial direction is held at the protruding position. Further, when the knock portion is knocked, the cam cylinder is knocked, and the writing shaft body protruding by the cam cylinder can be knocked. The rear shaft does not knock with respect to the front shaft, and only the knock portion at the rear of the writing instrument is knocked, so that the operability is good. Further, when exchanging or refilling the writing shaft body, it is possible to separate the front shaft and the rear shaft and expose the writing shaft body.
[0009]
According to a second aspect of the present invention, an engagement protrusion is formed at a rear end of the rear cylinder portion of the middle shaft according to the first aspect , and the engagement protrusion is formed on an inner surface of the rear shaft. It is locked to the step part.
[0010]
According to a third aspect of the present invention, the intermediate shaft according to the first or second aspect of the invention further includes a partition wall that is substantially perpendicular to the axial direction and has an insertion hole through which each writing shaft is inserted. Features.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
FIG. 1 thru | or 6 is a figure showing embodiment of the composite writing instrument of this invention. In the figure, the composite writing instrument has a front shaft 10 and a rear shaft 20.
[0013]
Specifically, the front shaft 10 includes one metal pipe 12, a tip 14 that is press-fitted into the tip of the metal pipe 12, a body screw portion 16 that is press-fitted into the rear end of the metal pipe 12, and a metal. It comprises an elastic gripper 18 that surrounds the outer periphery of the pipe 12 and is sandwiched between the tip 14 and the body screw portion 16. However, the configuration is not limited to this, and it is also possible to configure with fewer parts, for example, one part. On the outer peripheral surface of the body screw portion 16, a male screw portion 16a is formed for coupling the front shaft 10 to the middle shaft 30 described below.
[0014]
A middle shaft 30 is inserted between the front shaft 10 and the rear shaft 20. As shown in detail in FIG. 2, the middle shaft 30 is roughly between the front tube portion 32, the rear tube portion 34, and the front tube portion 32 and the rear tube portion 34, and is substantially perpendicular to the axial direction. And a partition wall 36. On the inner peripheral surface of the front tube portion 32, a female screw portion 32a that is screwed with the male screw portion 16a of the body screw portion 16 is formed, so that the front shaft 10 and the middle shaft 30 can be separated by screwing. Combined. Further, the rear cylinder portion 34 of the middle shaft 30 extends substantially concentrically into the rear shaft 20, and two locking projections 34 a projecting in the outer diameter direction are formed on the rear end edge of the cylinder portion 34 thereafter. (See FIG. 2 (c)), the locking projection 34a is locked to an engagement step portion 20a formed on the inner surface of the rear shaft 20. In addition, one projection 32b that projects in the outer diameter direction is also formed on the front cylinder portion 32 of the middle shaft 30, and this projection 32b is formed at the front end portion of the rear shaft 20 and extends in a range of 240 degrees in the circumferential direction. It is inserted into the circumferential groove 20b so as to be rotatable (see FIG. 3). Thus, the middle shaft 30 is coupled to the rear shaft 20 so as to be rotatable relative to the rear shaft 20 (in a range of 240 degrees) and immovable in the axial direction. As a result, the front shaft 10 and the rear shaft 20 are separated by releasing the screwing of the front tube portion 32 of the middle shaft 30 and the body screw portion 16 of the front shaft 10, while the front tube portion 32 of the middle shaft 30 is separated. And the body screw portion 16 of the front tube 10 are screwed together so that the front shaft 10 and the rear shaft 20 are connected to each other and the front shaft 10 and the rear shaft 20 are connected to each other (240). (In the range of degrees) and axially immovable.
[0015]
A plurality (specifically, three) of writing shaft bodies 40, 42, 42 are accommodated in the front shaft 10. One of these writing shaft bodies 40, 42, 42 is a mechanical pencil shaft, and the remaining two writing shaft bodies 42 (however, one of them is on the front side in FIG. 1). Are not visible) are pole pen shafts of different colors. However, the combination of the writing shaft bodies is not limited to this combination, and any writing shaft body including an eraser shaft can be combined. The rear portions of these writing shaft bodies 40, 42, 42 extend through the corresponding insertion holes 36a formed in the partition wall 36 of the central shaft 30 to the rear shaft 20, and at the rear end thereof are cams. Sliders 44, 44, 44 are attached. A spring 46, which is an elastic member, is inserted between each cam slider 44 and the partition wall 36, and each writing shaft body 40, 42, 42 is always urged rearward by each spring 46. .
[0016]
As shown in FIG. 4, each of the cam sliders 44, 44, 44 has a fan shape with an opening of 120 degrees when viewed from the axial direction. An engagement protrusion 44a having a sharp rear end is formed so as to engage with 50, and a rib 44b is formed on the outer peripheral surface of the engagement protrusion 44a. The rib 44b is fitted into a vertical groove 34b formed on the inner peripheral surface of the rear cylinder portion 34 of the middle shaft 30, and the cam slider 44 and the cam slider 44 are connected to the rib 44b by fitting the rib 44b with the vertical groove 34b. The writing shaft bodies 40, 42, and 42 are guided so as to be movable in the axial direction (see FIG. 4). In addition to the vertical grooves 34 b, vertical ribs 34 c are formed on the inner peripheral surface of the rear cylinder portion 34 of the middle shaft 30, and the vertical ribs 34 c guide the outer peripheral surface of the cam slider 44. . These vertical grooves 34 b and vertical ribs 34 c act as guide portions for the writing shaft body 42.
[0017]
A cam cylinder 50 is provided in the rear interior of the rear shaft 20. The cam cylinder 50 has a rib 50a formed on the outer peripheral surface thereof fitted in a longitudinal groove 20c formed on the inner surface of the rear end portion of the rear shaft 20 so as to be slidable. It can slide in the axial direction. As shown in FIG. 5, a hook-shaped cam projection 50b is formed at the tip of the cam cylinder 50, and an engagement recess 50c is formed at the tip of the cam projection 50b. The rear end of the engagement protrusion 44a of the cam slider 44 can be engaged. At the rear end of the cam cylinder 50, an eraser receiving portion 50d is formed, and an eraser 52 is inserted. Further, an eraser cover 54 that covers the eraser 52 is attached to the eraser receiving portion 50d, and the eraser cover 54 constitutes a knock portion that protrudes from the rear end of the rear shaft 20.
[0018]
In addition, a tail crown 56 is fixed to the rear end of the rear shaft 20 and prohibits the cam barrel 50 from protruding backward. Further, the base of the clip 58 is sandwiched between the tail crown 56 and the rear shaft 20.
[0019]
The operation of the composite writing instrument configured as described above will be described. First, FIG. 1 shows a state in which one writing shaft body 42 protrudes. In this state, the rear end of the engagement protrusion 44a of the cam slider 44 attached to the rear end of the writing shaft body 42 is The writing shaft body 42 is engaged with the engaging recess 50c of the cam barrel 50, and the writing shaft body 42 can be written with its tip protruding from the tip tool 14.
[0020]
When the rear shaft 20 is rotated with respect to the front shaft 10 from this state, the cam cylinder 50 is rotated together with the rear shaft 20, and the engagement between the engagement protrusion 44a and the engagement recess 50c is released, and the protruding writing The shaft body 42 moves backward while sliding on the slope of the cam projection 50 b of the cam cylinder 50 by the biasing force of the spring 46. Then, the engaging projection 44a of the cam slider 44 of the adjacent writing shaft body 40 or 42 moves forward while sliding on the inclined surface of the cam projection 50b of the cam barrel 50 according to the rotation direction, and after the engaging projection 44a. The writing shaft body 40 (or other writing shaft body 42) is engaged with the engaging recess 50c, so that the tip of the writing shaft body 40 protrudes from the tip 14 and writing can be performed. FIG. 6 shows a state in which the writing shaft body 40 has advanced. Since the writing shaft body 40 is a mechanical pencil shaft, it is necessary to knock in order to feed out the core. However, in the present invention, not the rear shaft 20 but the eraser cover 54 constituting the knocking portion is knocked. By knocking the eraser cover 54, the cam cylinder 50 is knocked, and the writing shaft body 40 is knocked via the slider 44 engaged with the engaging recess 50c of the cam cylinder 50. When the outer cylinder portion at the tip of the writing shaft body 40 abuts against the tip 14, the chuck C inside the writing shaft body 40 is pushed out, and the core L is fed out by the action of a known core feeding mechanism.
[0021]
Further, when the writing shaft body 40 is replenished, the male screw portion 16a of the front shaft 10 and the female screw portion 32a of the middle shaft 30 are unscrewed, and the front shaft 10 is replaced with the middle shaft 30 and the rear shaft 20 And the writing shaft body 40 can be exposed.
[0022]
As described above, in this embodiment, when the operation for selectively projecting the writing shaft bodies 40, 42, 42 is performed by rotating the rear shaft 20 relative to the front shaft 10, the rotation operation is performed. It is easy to perform the knock operation of the writing shaft body 40 by knocking the knock portion, so that the entire rear shaft 20 is not knocked and the operability is improved.
[0023]
The knock portion can be integrated with the cam cylinder 50 or can be composed of a plurality of members different from the cam cylinder 50.
[0024]
【The invention's effect】
As described above, according to the present invention, when the operation for selectively projecting the writing shaft is performed by rotating the rear shaft with respect to the front shaft, the rotating operation is easy to perform. Since the knocking operation is performed by knocking the knocking portion, the entire rear shaft is not knocked and the operability is improved.
[Brief description of the drawings]
FIG. 1 is an overall longitudinal sectional view showing an embodiment of a composite writing instrument of the present invention, and shows a state in which one writing shaft body (ball pen shaft) protrudes.
2A is a side view of the center shaft of the composite writing instrument in FIG. 1, FIG. 2B is a longitudinal sectional view of the center shaft, and FIG. 2C is a view taken in the direction of arrow 2c in FIG.
3 is a cross-sectional view taken along line 3-3 in FIG.
4 is a cross-sectional view taken along line 4-4 of FIG.
FIG. 5 is a perspective view of the cam cylinder of FIG. 1;
FIG. 6 is an overall longitudinal sectional view showing an embodiment of the composite writing instrument of the present invention, and shows a state in which one writing shaft body (a mechanical pencil shaft) protrudes.
[Explanation of symbols]
10 Front shaft 20 Rear shaft 30 Middle shaft 34b Vertical groove (guide section)
34c Vertical rib (guide section)
36 Partition wall 36a Insertion hole 40, 42 Writing shaft body 50 Cam cylinder 54 Eraser cover (knock part)

Claims (3)

It is inserted between the front shaft, the rear shaft, and the front shaft and the rear shaft, and is coupled to the front shaft in a separable manner and is coupled to the rear shaft so as to be rotatable and axially immovable. The front shaft and the rear shaft are separable from each other, and furthermore, a middle shaft that is connected to each other so as to be relatively rotatable and immovable in the axial direction, and is housed in the front shaft and constantly urged rearward. A plurality of writing shafts guided so as to be movable in the axial direction by the middle shaft, and provided in the rear shaft so as not to be rotatable relative to the rear shaft and movable in the axial direction. A cam cylinder that holds one writing shaft guided in the axial direction in a protruding position, and a knock portion that is integral with or connected to the cam cylinder and protrudes from the rear end of the rear shaft;
The nock Ri is capable Na knock writing shaft body that protrudes by the cam cylinder by the knock of the center pole, into the rear shaft has a cylindrical portion after extending substantially concentrically, within the rear tubular part the peripheral surface, the guide portion for guiding the axial movement of the writing shaft body is formed a composite writing tool according to claim Rukoto. The rear end of the rear tubular portion, the engaging projections are formed, the composite of the engaging projections, according to claim 1, wherein the locked engagement step portion formed on the rear shaft inner surface Writing instrument. 3. The composite writing instrument according to claim 1, wherein the central shaft further includes a partition wall that is substantially perpendicular to the axial direction and has an insertion hole through which each writing shaft is inserted.

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