JP6226588B2 - Intrusive writing instrument - Google Patents

Description

  The present invention relates to a retractable writing instrument in which a writing part in a protruding state is immersed by an operation of an operation part of a peripheral tube wall.

Conventionally, in this type of invention, for example, as in the invention described in Patent Document 1, a refill (20) having a writing portion (chip 21) on the front end side in the shaft tube (10), and the refill A spring (2) for urging the rearward, a first protrusion (31a) and a clip for locking the refill when it is advanced to the shaft cylinder and releasing the locked state by pressing in the radial direction (12) There is a retractable writing instrument provided with the above.
According to this retractable writing instrument, when the refill (20) is advanced by the pushing operation of the knock bar (30) at the rear end and the writing part (21) protrudes, the first protrusion (31a) is formed on the shaft tube (19). Locked to the first window portion (13) of the peripheral wall. Further, in this locked state, when the clip (12) is bent in the radially inward direction, the ball part (12a) of the clip pushes the first protrusion (31a) in the radially inward direction, and the first protrusion ( The locked state of 31a) and the 1st window part (13) is cancelled | released.

However, in the prior art, if the user or the like does not understand the operation method well, the clip (12) may be unintentionally pressed and the writing part may be immersed.
Further, as another invention, as shown in Patent Documents 2 and 3, the writing part is immersed by an operation with respect to a protruding part (the push button 6 or the locking release button 5) protruding radially outward from the shaft cylinder peripheral wall. However, when the writing instrument is placed on a desk or the like, the desk or the like may come into contact with the projection, and the writing unit may be unintentionally immersed.

Japanese Patent No. 4588838 Japanese Patent Publication No. 7-57558 Japanese Utility Model Publication No. 3-57091

  This invention is made | formed in view of the said conventional situation, The process made into the subject is providing the retractable writing instrument with the favorable operativity at the time of immersing a writing part.

  One means for solving the above-mentioned problems is: a core unit having a writing part on the front end side in the shaft tube, a biasing means for biasing the core unit rearward, and the core when advanced An engaging / disengaging mechanism that locks the unit to the shaft cylinder and can release the locked state by pressing inward in the radial direction so that the writing unit protrudes and retracts from the front end of the shaft cylinder by the advancement and retraction of the core unit. In the retractable writing instrument, an operating portion that does not protrude radially outward than other portions of the peripheral wall and that can be elastically dented radially inward is provided on the peripheral wall of the shaft cylinder. When the operation portion is recessed in the radial direction, the engaging / disengaging mechanism is pressed and released.

  Since this invention is comprised as demonstrated above, the operativity at the time of immersing a writing part can be improved.

It is a perspective view which shows an internal structure about the example of the retractable writing instrument which concerns on this invention by notching the half half part of a shaft cylinder. It is a side view of the same haunting type writing instrument. It is a longitudinal cross-sectional view which shows an example of a shaft cylinder, (a) and (b) mutually differ in a cross-sectional direction 90 degrees. It is a perspective view which shows an example of a belt-shaped member. It is a side view which shows the principal part in a cross section about an example of a seal cylinder. About an example of the seal cylinder, (a) is a rear view, (b) is a bb sectional view in (a). It is a disassembled perspective view which shows an example of a center unit. It is an internal structure figure of the same drawing type writing instrument, (a) shows the initial state where the writing part was immersed, and (b) shows the state where the core unit and the belt-like member were advanced a little. It is an internal structure figure of the same drawing type writing instrument, (c) shows the state where the belt-like member contacted the inclined guide part, and (d) shows the state where the core unit and the belt-like member were further advanced. It is an internal structure figure of the same penetrating type writing instrument, (e) shows a state in which the belt-like member is substantially in contact with the contacted portion, (f) is to further advance only the core unit to project the writing portion Indicates the state.

The first feature of the present embodiment is that a core unit having a writing part on the front end side in the shaft tube, a biasing means for biasing the core unit rearward, and the core when advanced An engaging / disengaging mechanism that locks the unit to the shaft cylinder and can release the locked state by pressing inward in the radial direction so that the writing unit protrudes and retracts from the front end of the shaft cylinder by the advancement and retraction of the core unit. In the retractable writing instrument, an operating portion that does not protrude radially outward than other portions of the peripheral wall and that can be elastically dented radially inward is provided on the peripheral wall of the shaft cylinder. When the operation portion is recessed in the radially inward direction, the engagement / disengagement mechanism is pressed and released.
According to this structure, a writing part can be immersed by operation which presses a shaft cylinder surrounding wall, and the operativity is favorable. In addition, since the operation part does not protrude outward from the peripheral wall of the shaft cylinder, a desk, a hand, a finger, etc. abut against the operation part, and the operation part is operated unintentionally and the writing part is immersed. Such an erroneous operation can be prevented.
Therefore, it is possible to provide a retractable writing instrument with few erroneous operations and good operability.

As a second feature, the engagement / disengagement mechanism includes a pressed portion that can be elastically deformed by being pressed radially inwardly on the outer peripheral side of the core unit, and the pressed portion moves toward the shaft when it moves forward. While being locked to a portion other than the operation portion on the peripheral wall of the cylinder, the locked state is provided so as to be released by being pressed by the operation portion.
According to this configuration, when the operation unit is pressed in the radially inward direction while the core unit is advanced and locked to the peripheral wall of the shaft tube, the operation unit is elastically recessed in the radially inward direction. The pressed portion of the release mechanism is pressed, and the locked state is released.

As a third feature, the pressed portion is locked to a portion other than the operation portion on the peripheral wall of the shaft cylinder so that it does not protrude outward in the radial direction from the outer peripheral surface of the shaft tube when it moves forward. The retractable writing instrument according to claim 2, wherein:
According to this configuration, since the pressed part does not protrude radially outward from the outer peripheral surface of the shaft tube, the pressed part comes into contact with a desk, a hand, a finger, etc., and the writing part is unintentionally immersed. Can be prevented.

As a fourth feature, an annular cut is provided in the peripheral wall of the shaft cylinder so as to penetrate the peripheral wall in the radial direction, and an inner portion of the cut is used as the operation portion.
According to this structure, the operation part which can be dented elastically in the radial direction can be set as a specific aspect with good operability and manufacturability.

As a fifth feature, the engagement / disengagement mechanism is configured to lock the core unit when it moves forward in the notch.
According to this configuration, the notch around the operation portion can be used also as a locked portion for locking the core unit when it moves forward (see FIGS. 1 and 2).

As still another preferred feature, a guide portion is provided on the peripheral wall of the shaft tube so as to guide the pressed portion in a concavo-convex shape and guide it forward (see FIGS. 1 and 2).
According to this configuration, it is possible to prevent the pressed portion from rattling in the circumferential direction when moving forward and not being locked by the locked portion on the shaft tube side.

As a more preferable feature, when the core unit moves forward, the pressed portion advances along the guide portion and is locked by the locked portion provided in the cut.
According to this configuration, the structure in which the core unit is guided and locked forward can be made a specific aspect with good manufacturability.

Next, a preferred specific example of the present embodiment having the above features will be described in detail with reference to the drawings.
In the following description, “front” means the tip direction of the shaft tube 10 (the direction in which the writing portion 22a protrudes), and “rear” means the direction opposite to the “front”. The “inner diameter direction” means a direction along the radial direction of the shaft tube 10 and toward the axis (center) of the shaft tube 10. Further, the “outer diameter direction” means a direction opposite to the inner diameter direction. The “axial cylinder axial direction” means a direction along the axial center (center) of the axial cylinder 10.

  This retractable writing instrument is provided with a shaft tube 10, a center unit 20 which is provided in the shaft tube 10 so as to be able to advance and retreat and has a writing portion 22 a (see FIG. 7) on the front end side, and the writing within the shaft tube 10. A seal cylinder 30 that covers the periphery of the portion 22a, a lid member 40 that closes the front end opening of the seal cylinder 30, and a lid member 40 that is in contact with the lid member 40 in a closed state in the longitudinal direction from the front side. The belt-like member 50 that extends to the rear of the shaft cylinder and is locked to the core unit 20, and the core unit 20 that is moved forward is locked to the shaft cylinder 10, and this locked state is inwardly in the radial direction. And an engagement / disengagement mechanism 60 that can be released by pressing, and with the advancement of the core unit 20, the lid member 40 is rotated forward to open, and the writing portion 22a projects forward from the seal tube 30 and the shaft tube 10, As the core unit 20 moves backward, the writing unit 22 And immerses the seal cylinder 30 and the barrel 10 closes by rotating the lid member 40 in the reverse direction.

The shaft cylinder 10 is a long cylindrical member, and may be formed from a single cylindrical member or may be configured by connecting a plurality of cylindrical members.
The front end side of the shaft tube 10 is provided with a tapered cylindrical front end portion 11 for projecting and retracting the writing portion 22a, and two belts to be described later are provided on the inner wall surface on the rear side of the front end portion 11. In order to bring the belt-shaped members 50 and 50 into contact with the inclined guide portions 12 and 12, respectively, which lead the belt-shaped members 50 and 50 forward and obliquely outward, respectively, along the inclined guide portions 12 and 12. Contacted parts 13 and 13.
Further, on the peripheral wall near the rear portion of the shaft tube 10, an engaging / disengaging mechanism 60 for engaging and disengaging the core unit 20 with the shaft tube 10 is configured, so that the guide portion 14, the locked portion 15, and the operation portion 16 are formed. Etc. are provided. Further, a guide recess 18 a that is in contact with the contact protrusion 33 on the front end side of the seal cylinder 30 is provided on the front end side in the shaft cylinder 10.

  The inclined guide portion 12 is a triangular cam having a projecting surface inclined outward in the radial direction toward the front, and sandwiches a virtual plane passing through the center of the shaft cylinder as shown in FIGS. Thus, two are provided symmetrically. According to the illustrated example, these two inclined guide portions 12 and 12 are arranged in a substantially V shape in plan view with the top side facing rearward.

The two contacted portions 13 and 13 are protrusions that intersect the front end portions of the two inclined guide portions 12 and 12 and extend radially outward, respectively, and project from the inner surface of the shaft tube 10 (FIG. 8). (See (a)).
In addition, the protruding amount in the radial direction of the inclined guide portions 12 and 12 and the contacted portions 13 and 13 is appropriately set so as not to interfere with the writing portion 22a when moving forward.

Further, according to the illustrated example, the guide portion 14 is a long hole that penetrates the peripheral wall of the shaft tube 10 and continues in the axial direction of the shaft tube (see FIGS. 1 and 2). Guide in the tube axis direction.
The locked portion 15 is a through hole provided on the peripheral wall of the shaft tube 10 at a position slightly away from the guide portion 14 toward the front side. The pressed portion 25b (specifically, a locking protrusion 25b1) described later. Lock.

The operating portion 16 is cut into the peripheral wall of the shaft tube 10 in a ring-like shape that penetrates the peripheral wall in the radial direction (according to the illustrated example, the opening is directed forward in a generally concave shape or a substantially U shape). By providing 16a, it is comprised so that the inner part of this notch 16a may be elastically bent and dented. The surface of the operation unit 16 is positioned so as to be substantially flush with a portion other than the operation unit 16 on the outer peripheral surface of the shaft tube 10.
The rear end side of the cut 16a communicates with the above-described locked portion 15 according to the illustrated preferred example. However, as another example, the cut 16a and the locked portion 15 are separated at intervals. It is also possible to provide it.

In addition, the code | symbol 17 in FIG.3 and FIG.8 is the elongate hole-shaped guide part which continues in the front-back direction. The guide portion 17 is fitted with a guided projection 21b4 (see FIG. 8) of the core unit 20 to be described later, and holds the core unit 20 forward and backward by a predetermined amount and cannot rotate.
Further, reference numeral 17a in FIG. 3 denotes a notch used for positioning in the circumferential direction or the like when a guided projection 21b4 (see FIG. 8), which will be described later, is fitted to the guide 17 in the manufacturing stage of the retractable writing instrument. It is.

Further, reference numeral 18 in FIGS. 3 and 8 denotes a guide convex portion that guides advancement and retreat of a seal cylinder 30 and a belt-like member 50 described later. The guide protrusion 18 is formed of two ribs that protrude from the inner peripheral surface of the shaft tube 10 and extend in the shaft tube axis direction, and has a guide recess 18a on the inner surface between these ribs.
The outer surface of the guide protrusion 18 in the circumferential direction of the shaft cylinder is loosely fitted in a notch 51a (see FIG. 4) of the belt-like member 50 described later to guide the advancement and retraction of the belt-like member 50.
The guide recess 18a is formed in a concave shape in plan view (see FIG. 3A) by the two ribs and the step portion between the ribs, and fits into a contact protrusion 33 of the seal cylinder 30 described later, The forward movement and circumferential rotation of the seal cylinder 30 are restricted.

  As shown in FIG. 7, the core unit 20 includes a holding cylinder 21, a tip 22 inserted on the front side of the holding cylinder 21, a batting 23 inserted on the rear side of the holding cylinder 21, and the batting 23 is configured integrally with a tail plug 24 that is connected to the holding cylinder 21 so as to cover the rear side of the cover 23 and an engagement / disengagement member 25 that is attached to the outer peripheral surface of the holding cylinder 21 and engages / disengages with the shaft cylinder 10. . The core unit 20 functions as an ink supply structure that supplies ink to the chip 22 (writing unit).

  According to the illustrated example, the holding cylinder 21 is formed in a stepped cylinder shape including a small-diameter cylinder part 21a and a large-diameter cylinder part 21b connected to the rear side of the small-diameter cylinder part 21a.

The small diameter cylindrical portion 21a is formed in a long cylindrical shape into which the rear side of the chip 22 can be inserted. A cylindrical protrusion 21a1 having a slightly larger diameter than the front and rear portions is provided on the front end side of the small diameter cylindrical portion 21a. The cylindrical projection 21a1 is slidably brought into contact with the inner surface of the annular seal cylinder 30 to maintain airtightness in the seal cylinder 30 and is held so as to advance and retract by a predetermined amount relative to the seal cylinder 30.
Near the rear end of the small-diameter cylindrical portion 21a, a plurality of (two in the illustrated example) engagement protrusions 21a2 and 21a2 are provided to be fitted to a belt-like member 50 described later. A step portion 21a3 is formed between the tube portions 21b.

  The engagement protrusions 21a2 are protrusions that protrude in the radially outward direction so as to face obliquely rearward. According to the illustrated example, two engagement protrusions 21a2 are provided approximately symmetrically on both sides in the radial direction of the small diameter cylindrical portion 21a.

  The stepped portion 21a3 is formed in an annular shape that is an inclined surface that faces the outer side of the rear oblique diameter so that a rear end side of a belt-like member 50 described later can be climbed over.

  Further, as shown in FIG. 1, a spring 26 (biasing means) is annularly mounted around the small-diameter cylindrical portion 21a. The spring 26 is a compression coil spring, and the rear end side thereof is received by the spring receiving portion 21a4 on the front side of the engagement protrusion 21a2 in the small diameter cylindrical portion 21a. The spring receiving portion 21a4 is formed so as to be fitted to the inner peripheral surface of the rear end seat portion of the spring 26 and to receive the rear end seat portion from the rear. According to the illustrated example, the spring receiving portion 21a4 has a stepped cross section continuous in the circumferential direction. Present.

Further, an annular recess 21b1 that is fitted so that the engagement / disengagement member 25 described later does not move in the front-rear direction and the engagement / disengagement member 25 are prevented from rotating in the circumferential direction near the center in the axial direction of the large-diameter cylindrical portion 21b. And a convex portion 21b2 to be engaged with the projection.
The annular recess 21b1 is an annular recess formed between the front and rear annular ribs, and holds the engagement / disengagement member 25, which will be described later, so that it cannot move back and forth.
The convex portion 21b2 fits in the concave-convex shape with respect to the engaging / disengaging member 25 and holds the engaging / disengaging member 25 in a non-rotatable manner.

Further, in FIG. 7, reference numeral 21 b 3 on the front end side of the large-diameter cylindrical portion 21 b is in a protruding state of the writing portion 22 a, and comes into contact with the contacted portion 19 that protrudes in the radial inward direction in the shaft cylinder 10. It is a restricting protrusion that restricts the forward movement of the unit 20, and is provided on both sides in the radial direction.
Further, in FIG. 8, reference numeral 21b4 is a guide projection that fits into the guide portion 17 of the peripheral wall of the shaft tube 10, and according to the illustrated example, it is provided only on one side in the radial direction.

7 and 8, reference numeral 21b5 is a long hole-like through portion that penetrates rearward substantially perpendicular to the protruding direction of the guided projection 21b4 (see FIG. 8), and is provided on both sides in the radial direction. It is done.
The through-hole 21b5 facilitates elastic deformation in the radially inward direction on the rear end side of the holding cylinder 21 when the holding cylinder 21 is inserted into the shaft cylinder 10 in the manufacturing stage of the retractable writing instrument. That is, when the holding cylinder 21 is inserted into the shaft cylinder 10 and assembled, the guided projection 21 b 4 gets over the rear end edge of the shaft cylinder 10 and fits into the guide portion 17. At this time, since the rear end side of the holding cylinder 21 is elastically deformed in the radially inward direction, the through portion 21b5 facilitates this elastic deformation.
The elastic deformation is suppressed by inserting and fitting the tail plug 24 to the rear end of the holding cylinder 21 after the holding cylinder 21 is inserted into the shaft cylinder 10.

  The chip 22 is formed by converging a large number of synthetic resin fibers in an axial shape, and has a writing portion 22a that is slightly thicker than the rear portion near the front end portion thereof. The writing portion 22a is formed in an appropriate shape according to the use of the retractable writing instrument, such as a bullet shape or an oblique cut shape, and the front end of the holding cylinder 21 is inserted in the holding cylinder 21 at the rear side of the tip 22. Projects forward from the section.

  The batting 23 is formed by impregnating a large number of synthetic resin fibers accommodated in a cylindrical thin film with ink and inserted into the rear end side of the holding cylinder 21. In the holding cylinder 21, the rear end side of the tip 22 is inserted into the front end side of the batting 23. Therefore, the ink in the batting 23 is guided to the front end side of the chip 22 by capillary force.

The tail plug 24 is a bottomed cylindrical member, and after the holding cylinder 21 and the batting 23 are mounted on the shaft cylinder 10, the rear end portion of the holding cylinder 21 is covered so as to cover the rear end side of the batting 23. Press-fit to Reference numeral 24a in FIG. 7 denotes an annular protrusion that is fitted over a protrusion (not shown) on the inner peripheral surface of the holding cylinder 21 to be prevented from being removed.
The tail plug 24 protrudes rearward from the rear end of the shaft tube 10 and functions as a knock operation portion.
Note that the space in the holding cylinder 21 containing the batting 23 is hermetically sealed by pressure contact over the entire circumference between the annular protrusion 21b6 formed on the rear inner peripheral surface of the holding cylinder 21 and the distal outer peripheral surface 24b of the tail plug 24. (See FIG. 7).

  The engagement / disengagement member 25 is formed of an elastically bendable metal material, and is fitted with an outer periphery of the holding cylinder 21. The engagement / disengagement member 25 protrudes from the annular engagement portion 25a to the rear obliquely outer diameter and has a diameter. It is comprised from the to-be-pressed part 25b which can be elastically bent inward (refer FIG. 7).

  The annular locking portion 25a is elastically expanded in diameter and is formed in an end-like annular shape so as to be fitted into the annular recess 21b1 of the holding cylinder 21. At both ends in the circumferential direction of the annular locking portion 25a, locking holes 25a1 that are fitted to the convex portions 21b2 on the outer periphery of the holding cylinder 21 to prevent rotation are provided (see FIG. 7).

The pressed portion 25b is locked to a portion other than the operation portion 16 on the peripheral wall of the shaft tube 10 when moving forward in the shaft tube 10, and the locked state is pressed by the operation portion 16 to be released. Is provided.
If it demonstrates in detail, this to-be-pressed part 25b will adjoin or contact the operation part 16 in the front side rather than the latching protrusion 25b1 and the latching protrusion 25b1 which can be engaged / disengaged with the to-be-latched part 15 of the shaft cylinder 10 peripheral wall. It has a pressed surface 25b2, and a hook 25b3 projecting on both sides of the locking projection 25b1 and the pressed surface 25b2 in the circumferential direction (see FIG. 7).

  For example, the locking projection 25b1 is formed by bending a flat plate material constituting the engaging / disengaging member 25 into a substantially triangular cross section by pressing or the like, and being locked to the locked portion 15 of the shaft tube 10. The height is such that it does not protrude radially outward from the outer peripheral surface of the shaft tube 10.

  As shown in FIG. 10 (f), the pressed surface 25 b 2 is arranged so as to be close to or in contact with the back side of the operation unit 16 in a state where the locking projection 25 b 1 is locked to the locked portion 15. .

  The flange portion 25b3 abuts against the inner peripheral surface of the shaft tube 10 so that the locking projection 25b1 does not protrude radially outward from the outer peripheral surface of the shaft tube 10. Accordingly, the dimension from the outer surface of the flange 25b3 to the protruding end of the locking projection 25b1 is set smaller than the thickness of the peripheral wall of the shaft tube 10.

The seal cylinder 30 is a substantially cylindrical member that covers the periphery of the front end side of the holding cylinder 21 that protrudes from the writing portion 22 a, and is attached to the holding cylinder 21 in an annular shape.
The rear end side inner peripheral surface of the seal tube 30 is in sliding contact with the front end side outer peripheral surface of the holding tube 21 (specifically, the cylindrical protrusion 21a1 shown in FIG. 7), and extends from the seal tube 30 to the holding tube 21. An annular protrusion 31 is provided to maintain the internal airtightness (see FIG. 5).
A stepped portion 32 that receives the front end of a spring 26 (see FIG. 1) that biases the holding cylinder 21 rearward is provided on the outer peripheral surface of the seal cylinder 30 on the rear end side.
In addition, contact protrusions 33 (see FIGS. 1 and 5, etc.) are provided on both sides in the radial direction on the front end side outer peripheral surface of the seal cylinder 30. The abutment protrusion 33 abuts on the guide recess 18 a in the shaft tube 10 and restricts the forward movement of the seal tube 30.
A fitting projection 34 for mounting the lid member 40 is provided on the outer peripheral surface of the front end side of the seal cylinder 30.

  The lid member 40 includes a fitting piece portion 41 fitted to the fitting protrusion 34, a lid main body portion 42 formed in a cross shape with respect to the fitting piece portion, the fitting piece portion 41 and the lid main body portion. And connecting part 43 (biasing means) for connecting 42, and flexing the connecting part 43 to rotate the lid main body part 42. The lid member 40 is integrally formed of a synthetic resin material (for example, polypropylene or the like) that can be elastically bent.

The lid main body 42 is formed in a disc shape that can be fitted and removed on the inner edge of the front end opening of the seal cylinder 30.
On the inner surface (the left end surface according to FIG. 5) of the lid main body portion 42, a raised portion 42a located near the center and a protrusion 42b located around the raised portion 42a are provided.
The raised portion 42 a is formed in a convex curved shape that protrudes into the seal cylinder 30 when the lid member 40 is closed. In the unlikely event that the lid main body 42 bites into the seal tube 30 and becomes difficult to open, the raised portion 42a receives the writing portion 22a that advances, and facilitates the opening of the lid main body 42.
A plurality of protrusions 42b are provided at intervals in the circumferential direction, and in the closed state of the lid member 40, the lid member 40 is centered by being close to or in contact with the inner edge of the front end side of the seal cylinder 30, and the closed lid member 40 is transported. Prevents the seal from being damaged due to shakiness in the radial direction due to vibration during use.

The connecting portion 43 (biasing means) is formed in a substantially L shape that connects the lid main body portion 42 to the fitting piece portion 41 in a substantially fully opened state, and is elastically bent to open the front end opening of the seal cylinder 30. And the front end opening is opened by restoring in the opposite direction.
The connecting portion 43 only needs to have a structure that supports the lid main body portion 42 so as to be rotatable with respect to the seal cylinder 30 and urges the lid main body portion 42 in the opening direction. A mode in which a shaft portion for rotating the lid main body portion 42 with respect to the seal cylinder 30 and a biasing means (for example, a torsion spring or a leaf spring) for biasing the lid main body portion 42 in the opening direction are provided. It is also possible.

Further, on the outer surface of the lid member (the right end surface according to FIG. 5), an engagement / disengagement piece 42c that can be engaged / disengaged in the radial direction with respect to the belt-shaped member 50 described later, and a belt shape when bent in the radial direction A regulating protrusion 42d located on the radially outward side of the member 50 is provided.
As shown in FIG. 6B, the engaging / disengaging piece 42 c is formed in a protruding piece shape having concave portions 42 c 1 and 42 c 1 on both ends in the radial direction, and is disposed from the center of the lid main body 42. A belt-like member 50 described later is engaged with and disengaged from the recesses 42c1 and 42c1.
The restricting protrusion 42d is a substantially L-shaped protrusion that protrudes in the radial direction from the radial end portion side of the lid main body 42 (see FIG. 6B). This prevents the belt portion 52 from rotating in the opening direction. Two of the restricting protrusions 42d are provided so as to be symmetrically located on both sides in the radial direction.

  Further, as shown in FIG. 4, the belt-shaped member 50 includes a cylindrical portion 51 that is annularly inserted into the front end side of the core unit 20 and two belt portions 52 and 52 that protrude from the front end of the cylindrical portion 51. , A synthetic resin material that includes two locking pieces 53 and 53 that protrude rearward from the rear end of the cylindrical portion 51 and are locked to the core unit 20 and can be elastically bent (for example, Are integrally formed of polypropylene or the like.

  The cylinder part 51 is a substantially cylindrical member into which the front end side (specifically, the small diameter cylinder part 21a) of the holding cylinder 21 and the spring 26 can be loosely inserted, and has a notch part 51a on the peripheral wall thereof. The notches 51a are provided symmetrically on both sides in the radial direction, loosely fitted on the guide protrusions 18 (see FIG. 3 and FIG. 8 (a), etc.) on the inner surface of the shaft tube 10, and the belt-like member 50 is in the circumferential direction. Guide to smoothly advance and retreat back and forth without rotating to

The two belt portions 52, 52 are provided substantially in parallel with an interval so as to be positioned on both sides of the central portion of the shaft cylinder.
Each belt portion 52 has a central portion in the longitudinal direction in contact with the closed lid member 40 (specifically, the lid main body portion 42) from the front side, and both end portions are pivoted along the outer peripheral surface of the seal cylinder 30. It is formed in a substantially U shape extending to the rear of the cylinder, and its rear end is connected to the cylinder 51.
The belt portion 52 can be elastically bent in the radial direction, and is in an initial position substantially parallel to the axis as shown in FIG. When it moves forward, it slides into contact with the inclined guide portion 12 in the shaft tube 10 and bends radially outward, and when it moves backward, it restores radially inward.
The front end of the belt 52 is in the initial position in contact with the front surface of the fully-closed lid member 40 (see FIGS. 1 and 8A), and the recess 42c1 of the engagement / disengagement piece 42c in the lid member 40 (FIG. 6). (See (b)), it fits in an irregular shape from the radially outward side.

The locking pieces 53 are provided at intervals so as to be located on both sides of the central part of the shaft cylinder (see FIG. 4).
Each locking piece 53 is provided with a long-sliding slide engaging hole 53a that fits to the engaging projection 21a2 of the holding cylinder 21 so as to be slidable back and forth.

  Further, the engagement / disengagement mechanism 60 is a mechanism configured by the engagement / disengagement member 25 described above, the guide portion 14 of the peripheral wall of the shaft tube 10, the locked portion 15, the operation portion 16, and the like, and the core unit 20 has advanced. At this time, the locking protrusion 25b1 of the pressed portion 25b is locked to the locked portion 15 on the shaft tube 10 side, and this locked state is released by a pressing operation on the operation portion 16.

Next, the characteristic operation and effect of the above-described retractable writing instrument will be described in detail.
First, in the initial position where the writing portion 22a is immersed, the center unit 20 is positioned so that the guided projection 21b4 is in contact with or close to the rear end edge of the guide portion 17 as shown in FIG. To do. In this state, the seal cylinder 30 is urged forward by the spring 26 to bring the contact protrusion 33 into contact with the guide recess 18 a on the inner peripheral surface of the shaft cylinder 10. Further, the belt-like member 50 is engaged with the engagement / disengagement piece 42c by bringing each belt portion 52 on the front end side into contact with the front surface of the lid member 40 in the closed state.

  In the initial state, the engagement piece 53 on the rear end side of the belt-like member 50 is shown in FIG. 8A and the like by engaging the slide engagement hole 53a with the inclined engagement protrusion 21a2. Thus, it is bent in the radially inward direction and is close to the stepped portion 21a3. That is, since the elastic force by the spring 26 acts between the belt-like member 50 and the holding cylinder 21, the elastic piece 53 causes the locking piece portion 53 to be on the rear end inclined surface of the engaging protrusion 21a2. When pressed, it bends toward the center of the shaft cylinder, and the rear end of the locking piece 53 comes close to the stepped portion 21a3. As another example, in the initial state, the rear end of the locking piece portion 53 can be brought into contact with the stepped portion 21a3.

Next, as shown in FIG. 8B, when a forward pressing force is applied to the core unit 20 by a knocking operation on the tail plug 24, the core unit 20 compresses the spring 26 while compressing the spring 26. Move forward to narrow the distance from 30. During this advancement, the stepped portion 21a3 of the core unit 20 contacts the rear end of the belt-like member 50 (specifically, the rear end of the locking piece 53), and the belt-like member 50 advances integrally. Further, this advancement is guided by the fitting between the locking projection 25b1 and the guide portion 14, the fitting between the guided projection 21b4 and the guide portion 17, or the like.
With this advance, the belt portion 52 at the front end of the belt-like member 50 also advances, so that the lid member 40 gradually opens. The opening of the lid member 40 at this time is basically due to the restoring force of the connecting portion 43 (see FIG. 5), but even if the lid member 40 bites into the seal cylinder 30 and is difficult to open, the recess 42c1. Since the belt portion 52 is engaged with the belt portion 52 (see FIG. 6) and the engagement / disengagement piece 42c on the front surface of the lid member 40 is pulled forward by the belt portion 52, the operation is smoothly performed.

As shown in FIG. 9C, when the core unit 20 further advances, the belt portion 52 at the front end of the belt-like member 50 contacts the inclined guide portion 12 on the inner surface of the shaft tube 10. When the core unit 20 moves forward, the belt portion 52 bends radially outward along the inclined guide portion 12 and is detached from the engagement / disengagement piece 42c. Then, the lid member 40 gradually opens as the belt portion 52 is bent by the restoring force in the opening direction.
9 to 10, one belt portion 52 is omitted in order to clearly show the lid member 40.

Next, the belt-like member 50 makes the belt portion 52 contact the contacted portion 13 and cannot advance, and the lid member 40 is substantially fully opened by an elastic restoring force (see FIG. 10E). The locking piece 53 at the rear end of the belt-shaped member 50 expands in diameter along the inclined surface of the stepped portion 21a3 so as to ride over the stepped portion 21a3 so that only the core unit 20 is relative to the shaft tube 10. The writing portion 22a protrudes forward from the opening at the front end of the seal cylinder 30.
In the fully open state of the lid member 40, as shown in FIG. 10E, the L-shaped restricting protrusions 42d on both sides of the lid member 40 abut against the inner surface of the belt portion 52. It is possible to prevent the belt portion 52 from turning around in the radially outward direction from becoming impossible to close.

Then, as shown in FIG. 10 (f), when the core unit 20 further advances, the core unit 20 enters between the two locking pieces 53 and 53 of the belt-like member 50 in a state where the advancement is impossible. The writing portion 22a is projected from the front end of the shaft tube 10.
This protruding state is maintained by the locking projection 25b1 of the pressed portion 25b constituting the engagement / disengagement mechanism 60 being locked to the locked portion 15 on the shaft tube 10 side.

  In order to immerse the writing portion 22a from the protruding state, the operation portion 16 on the peripheral wall of the shaft tube 10 may be pressed and bent in the radially inward direction. That is, when the operation part 16 bends in the radial direction, the operation part 16 comes into contact with the pressed part 25b and presses and bends the pressed part 25b in the radial direction. Therefore, the locking protrusion 25b1 of the pressed portion 25b is detached from the locked portion 15, and the retraction of the core unit 20 is started by the elastic force of the spring 26. This backward movement is performed by an operation reverse to the above description.

  That is, when the engagement / disengagement member 25 is detached from the shaft cylinder 10, first, only the core unit 20 (specifically, the holding cylinder 21, the tip 22, the batting 23, the tail plug 24, and the engagement / disengagement member 25) Due to the elastic force, it slides backward between the locking pieces 53 and 53 (see FIGS. 10 (f) and 10 (e)), and the writing portion 22 a is immersed in the shaft tube 10.

  Then, when the retreat of the core unit 20 proceeds, as shown in FIG. 10 (e), when the locking piece 53 is positioned in a state of being hooked on the engaging protrusion 21 a 2 on the front side of the stepped portion 21 a 3, thereafter, As shown in FIG. 9 (d), the belt-like member 50 is also pulled backward by the engagement protrusion 21a2. The backward movement of the belt-like member 50 starts from a position where the writing part 22a is almost immersed in the seal cylinder 30 as shown in FIG.

  During the subsequent retraction of the belt-shaped member 50, as shown in FIGS. 9D to 9C, the belt portion 52 is restored along the inclined guide portion 12 toward the center of the shaft cylinder 40 while being covered. The front surface of the cover member 40 is pushed rearward to close the lid member 40.

  Further, when the core unit 20 and the belt-like member 50 are retracted, as shown in FIG. 8B, the front end of the belt portion 52 is separated from the inclined guide portion 12, and the two belt portions 52, 52 become substantially parallel. Thus, the cover member 40 is locked to both sides of the engagement / disengagement piece 42c and presses the lid member 40 backward.

  After the retreat, as shown in FIG. 8A, the writing portion 22a is completely immersed in the seal cylinder 30, the lid member 40 is fully closed, and the belt portion 52 is disposed on the front surface of the lid member 40. The pressed part 25b is positioned near the rear end in the guide part 14 and is in an initial state.

  Therefore, according to the above embodiment, the lid member 40 in the closed state can be urged by the belt-like member 50 to improve the sealing performance in the seal cylinder 30, and in addition, the belt-like member 50 can be engaged with and disengaged from the lid member 40. The lid member 40 can be smoothly opened and closed, and the writing portion 22a can be smoothly advanced and retracted at a suitable timing.

  Moreover, in the protruding state of the writing portion 22a, the writing portion 22a can be easily immersed by an operation of pressing the peripheral wall of the shaft tube 10, and the operation portion 16, the pressed portion 25b, etc. are more than the peripheral wall of the shaft tube 10. Since it has a structure that does not protrude outwardly, an erroneous operation such that the writing unit 22a is unintentionally brought into contact with an object such as a desk, hand, or finger against the operation unit 16, the pressed portion 25b, etc. Can be prevented.

  Accordingly, it is possible to provide a retractable writing instrument that has good sealing performance when stored in the writing section, operability when retracted, and operability.

  In addition, according to the said Example, although the cover member 40 of another member was assembled | attached with respect to the seal cylinder 30, these seal cylinders 30 and the cover member 40 can also be made into an integral member.

  Moreover, according to the said Example, although it was made to have the two belt parts 52 and 52 in the front-end side of the belt-shaped member 50, as an other example, the aspect which made the belt part 52 single, or the belt part 52 is provided. It is also possible to adopt a mode in which three or more are provided in the circumferential direction.

  Moreover, according to the said Example, although the belt part 52 was made into the aspect which slidably contacts to the one side surface of the inclined guide part 12, and as an example, the belt part 52 is uneven | corrugated with respect to the inclined guide part 12. It is also possible to adopt a mode of being bent while being forwardly fitted.

Moreover, in the said Example, although the to-be-latched part 15 was formed so that the shaft cylinder 10 surrounding wall might be penetrated, this to-be-latched part 15 should just be the structure which can be engaged / disengaged with the latching protrusion 25b1, As another example of the locked portion 15, a recess provided on the inner peripheral surface of the shaft tube 10 can be used.
Similarly, the guide portions 14 and 17 can be grooves provided on the inner peripheral surface of the shaft tube 10.

  Moreover, in the said Example, although it was set as the operation part 16 in which the inner part of the notch | incision 16a of the axial cylinder 10 surrounding wall was dented elastically, as another example, a part of peripheral wall of the axial cylinder 10 was made into an elastic body ( For example, it is possible to use an operation unit that is made of an elastomer resin) and that can elastically dent the elastic body.

  Moreover, in the said Example, although the surface of the operation part 16 was arrange | positioned substantially flush with parts other than the operation part 16 in the axial cylinder 10 outer peripheral surface, as another example, the surface of the operation part 16 is made into the axial cylinder 10. It is also possible to adopt a mode in which the outer peripheral surface is recessed from a portion other than the operation portion 16.

  Moreover, in the said Example, although the operation part 16 and the to-be-pressed part 25b were provided in one place in the surrounding wall of the axial cylinder 10, as another example, these operating part 16 and the to-be-pressed part 25b are provided in the axial cylinder 10 surrounding wall. It is also possible to improve the operability by providing a plurality in the circumferential direction and / or the axial direction.

DESCRIPTION OF SYMBOLS 10: Shaft cylinder 12: Inclined guide part 13: Contact part 14, 17: Guide part 15: Locked part 16: Operation part 16a: Cutting 20: Center unit 21: Holding cylinder 21a2: Engagement protrusion 21a3 : Step part 22: Tip 22a: Writing part 23: Filling 24: Tail plug 25: Tail plug 25: Engaging / disengaging member 26: Spring (biasing means) 25a: Annular locking part 25b: Pressed part 30: Seal cylinder 40: Lid member 42b : Projection 42c: Engaging / disconnecting piece 42d: Restricting projection 43: Connection portion (biasing means) 40: Lid member 50: Belt-like member 52: Belt portion
53: Locking piece 60: Engaging / disengaging mechanism

Claims (5)

Inside the shaft cylinder, a core unit having a writing part on the front end side, urging means for urging the core unit rearward, and the core unit when it moves forward are locked to the shaft cylinder, and this In the retractable writing instrument comprising an engagement / disengagement mechanism capable of releasing the locked state by pressing in the radially inward direction, wherein the writing unit protrudes and retracts from the front end of the shaft cylinder by the advancement / retraction of the core unit,
An operation portion that does not protrude radially outward than other portions of the peripheral wall and that can be elastically recessed toward the radially inward side is provided on the peripheral wall of the shaft cylinder. A retractable writing instrument which is configured to press and release the engaging / disengaging mechanism when recessed inward. The engagement / disengagement mechanism includes a pressed portion that can be elastically deformed by being pressed radially inward on the outer peripheral side of the core unit,
The pressed portion is provided so as to be locked to a portion other than the operation portion on the peripheral wall of the shaft cylinder when being advanced, and to be released by being pressed by the operation portion. The retractable writing instrument according to claim 1.   The pressed portion is locked to a portion other than the operation portion on the peripheral wall of the shaft cylinder so as not to protrude radially outward from the outer peripheral surface of the shaft tube when the pressed portion moves forward. Item 2. An intrusive writing instrument.   4. The intrusion / intrusion according to claim 1, wherein the peripheral wall of the shaft cylinder is provided with an annular cut having an end that penetrates the peripheral wall in a radial direction, and an inner portion of the cut is used as the operation portion. Formula writing instrument. 5. The retractable writing instrument according to claim 4 , wherein the engagement / disengagement mechanism is configured to lock the core unit at the time of advancement to the notch.

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