JP2606589Y2 - Double writing instrument - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the provision of a double-type writing instrument in which the tips of a plurality of writing bodies are made to be able to come and go alternately at a tip end of a front shaft, and an eraser is made to come and go from the rear end of a cap.

[0002]

2. Description of the Related Art Conventionally, as an example of a double-type writing instrument, as shown in Japanese Utility Model Application Laid-Open No. 64-3491 by the same applicant, a sliding groove for guiding two writing objects is provided on a front shaft. The front end has a guide tube fixed to the guide tube and a cam slope contacting a sliding piece attached to two writing bodies fitted to the guide tube, and the rear end forms a knock portion to the cap. Equipped with a cylindrical cam mounted so as to be movable in the axial direction and integrated in the circumferential direction, and by selectively rotating the cap with respect to the front shaft, two writing bodies can be selectively placed at the front end of the front shaft. There are multiple writing instruments that can appear and disappear.
Further, as a cited example of the present application, there is a double writing instrument in which an eraser is made to protrude and disappear by rotating a crown protruding from the rear end of a cap as seen in Japanese Utility Model Application Laid-Open No. 60-120889 by the present applicant. .

[0003]

The above cited reference has the problem that metal parts are used in many parts, the structure is complicated, the number of parts increases, and the cost increases.

[0004]

The double writing implement of the present invention devised to solve the above-mentioned problem has the following configuration and features. An engaging portion is provided for fitting the front end of the resin-made shaft and the front end of the resin-made middle shaft in a non-rotatable and non-removable state, and the two are fixed to each other. A return spring is provided between the guide cylinder and the sliding piece, and at least one of the writing pieces with the moving piece fixed to the rear end is made of a mechanical pencil. Fitted, the cylindrical cam is rotatably retained with respect to the central shaft, and each sliding piece is alternately moved back and forth by rotation of the cylindrical cam with respect to the front shaft or the central shaft by abutting on the cam slope of the cylindrical cam, In a compound writing tool in which the tip of each writing body can be selectively protruded and retracted from a tip end of a front shaft, a substantially L-shaped window having a vertical groove and a circumferential groove connected to a rear side surface of the center shaft through a narrow portion. Part is drilled and the cam slope displaced in the axial direction is A protrusion is provided on the side surface of a cylindrical cam provided in a circumferential shape at the portion, and the protrusion is elastically fitted into the circumferential groove so that the cylindrical cam can rotate and move in a certain range with respect to the guide cylinder and the center shaft. Lock the stopper, and move the sliding pieces alternately in the front-rear direction by rotating the cylindrical cam with respect to the front shaft or the center shaft. Only when the cylindrical cam is axially shifted, the core can be extended, and a cylindrical part having a slit behind the cylindrical cam and a cap having a cylindrical part integrally outside the cylindrical part are provided. A resin crown having a spiral groove formed in the inner hole is fitted in a state where the cylindrical portion of the cylindrical cam is fitted in the inner hole, and the crown is fixed to the cap so that it can only rotate. At the same time, an eraser with an eraser fixed in the cylindrical portion of the cylindrical cam The holder is provided with its protrusion fitted in the slit and spiral groove, and the tip of the cursive writing comes out by rotating the cap with respect to the front axis or the central axis, and the eraser comes out by rotating the crown with respect to the cap. It becomes possible. As described above, the dual writing implement of the present application has a simplified number of parts and a simple structure, so that assembly is easy and cost reduction is possible, and even if a drop impact is applied to the rear end of the cap, the projection of the cylindrical cam is attached to the front wall of the circumferential groove. Since it is a design that does not abut, it is possible to prevent breakage of projections and the like.

[0005]

1 and 3 show an embodiment of the present invention. The dual writing implement of the present invention has a center shaft 1 and a front shaft 3 integrally provided with a guide cylinder 2 as a guide portion, a cap 4 integrally provided with a cylindrical cam 5, a pair of sliding pieces 6, a 6 ｀ mechanical pencil writing body 7, and a ballpoint pen. The cursive body 8, the crown 34, the eraser holder 40, and the eraser 45 are main components. First, the center shaft 1 is made of resin, and as shown in FIG. 1, an axially long guide groove 9 opened on the side surface from a substantially central portion to a rear end.
And a guide cylinder 2 having a similar guide groove 9 # on the side surface opposite to the guide tube. The front half of the guide tube 2 is provided with a tube portion 10 having a partition portion 16 having holes 32, 32 ° communicating with the respective guide grooves 9, 9 ° and having an open front end,
A stepped portion 31 is provided at the rear end of the cylindrical portion 10, and a bulging engagement portion 13 is formed on a front outer peripheral portion of the stepped portion 31.

On the rear side surface of the center shaft 1, as shown in FIG. 2, a vertical groove 18 is connected to a circumferential groove 19 through a slope 46 on the front side, and a substantially L-shaped window portion is formed. Are drilled. As will be described later, the projection 17 of the cylindrical cam 5 is inserted from the vertical groove 18, and the projection 17 elastically expands the inclined surface 46, passes through the narrow portion 47, and enters the circumferential groove 19. The cylindrical cam 5 rotates while the projection 17 abuts on the rear wall of the circumferential groove 19 in the circumferential direction, so that the writing part of the writing body 8 such as the mechanical pencil 7 or the ballpoint pen alternately protrudes and retracts from the front end of the front shaft. Become. The circumferential groove 19 is provided with a wide groove 48 so that the cylindrical cam 5 can move axially at the position of the projection 17 when the mechanical pencil 7 protrudes. The rear wall 50 of the circumferential groove 19 is so arranged that the cylindrical cam 5 cannot be shifted substantially at the position of the projection 17 when the projection is made.
A narrow groove 49 is provided between the a and the rear wall 50c to connect the inclined surface 50b. As will be described later, the cylindrical cam 5
Is set so that the wall 20 of the cap 4 abuts on the rear end of the center shaft 1 and the front end of the projection 17 does not abut on the front wall 51 of the circumferential groove 19 when advancing.

[0007] The front end of the shaft 3 is tapered, and the front end of the shaft 3 has an inner step 27 at the end of the inner hole. In the rear end hole, an engagement groove 12 is provided, which engages with an engagement portion 13 provided on the outer peripheral portion of the cylindrical portion 10 of the guide cylinder, and prevents the cylindrical portion 10 from slipping out and rotating. . The cylindrical portion 10 and the front shaft 3 are detachably fixed by an appropriate force. (Showa 6
(Same as the configuration of the front shaft in JP-A-4-3491)

The cap 4 is made of resin, and has a circumferential wall 20 integrally supporting the cylindrical cam 5 in the inner hole at the front. Further, a protruding engagement portion 33 is formed on the shaft portion 4b having a slightly smaller diameter at the rear of the outer peripheral portion. The cylindrical cam 5 has a cylindrical shape, and has a cam slope 14 that is displaced circumferentially back and forth at a front end edge, and a notch 15 is formed at the foremost end of the cam slope 14. Further, on the side surface of the cylindrical cam 5, a longitudinal groove 1 of the center shaft 1 is provided.
8, a projection 17 is formed which elastically fits into the circumferential groove 19 and rotates and prevents it from falling off within a certain range (approximately 180 degrees).

The cylindrical cam 5 has a cylindrical portion extending rearward, and further has a long slit 37 formed behind the step portion 38. On the other hand, the resin crown 34 has an outer cylindrical portion 34a formed at the rear, and an inner cylindrical portion 35 is provided inward toward the front, and a spiral groove 36 is formed in an inner hole of the inner cylindrical portion 35. Is formed. An engaging portion 34b having a circumferential groove is formed on the inner surface of the outer cylindrical portion 34a.

The inner cylindrical portion 35 of the crown 34 is fitted in the rear inner hole of the cap 4 while being fitted on the outer periphery of the cylindrical portion having the slit 37, and the engaging portion of the outer cylindrical portion 34a is fitted. 34
b is elastically fitted to the engaging portion 33 of the shaft portion 4b of the cap, and the crown 34 is fixed to the cap 4 so as to be rotatable only.

Further, an eraser holder 40 having an eraser 45 fixed to the rear end is mounted in the cylindrical portion having the slit 37 of the cylindrical cam. The eraser holder 40 has a pair of elastic pieces 43 formed at the rear to sandwich an eraser 45, and has an engaging projection 44 on the inner surface of the elastic piece 43. A projection 42 is formed on the outer periphery of the front cylindrical portion 41. The eraser holder 40 has a protrusion 42 and an elastic piece 43 fitted in the slit 37 of the cylindrical portion.
6 and is disposed in the tubular portion. In this state, when the outer cylindrical portion 34a of the crown is rotated with respect to the cap 4, the eraser holder 40 moves forward and backward, and the eraser 45 can be protruded and retracted from the rear end hole 39 of the crown.

The sliding piece 6 has a projection 22 on the outer surface, a central portion protruding from the rear end surface of the projection 22, and both sides thereof have a cam having substantially the same gradient as the cam slope 14 of the cylindrical cam 5 described above. It has a slope. Further, a hole is provided which abuts against the flange portion 24 of the core pipe 23 to protrude and fit the rear of the core pipe 23 long. The sliding piece 6 # has a projection 22 # and a cam slope like the sliding piece 6, and a locking portion 26 for fixing the rear end of the writing body 8 such as a ball-point pen is provided at the tip. Incidentally, the locking portion may be formed in a pipe shape and the rear end of the writing body may be fitted.

The mechanical pencil 7 has a built-in general chuck mechanism, is joined to the core pipe 23 via a joint 29 connected to the chuck mechanism at the rear end, and has a flange portion 24 provided behind the core pipe 23. The sliding piece 6 is fitted in contact with the sliding piece 6, and the rear end hole of the core pipe 23 protruding from the rear end of the sliding piece 6 is closed by a tail plug 25 or the like. The leading of the lead is performed by moving the chuck by the axial movement of the sliding piece 6 in a state where the step 28 at the tip end of the mechanical pencil 7 is in contact with the inner step 27 of the front shaft 3.

Next, a description will be given in assembling order. A mechanical pencil 7 and a pen 8 such as a ball-point pen have respective sliding pieces 6, 6 # connected to the rear end thereof, and each of the above-described center axis guide cylinders 2 is connected. It is movably fitted in the guide grooves 9, 9 ｀, and the front end face of each sliding piece 6, 6 ｀ and the partition 1 on the front of the guide grooves 9, 9 ｀.
6 is urged rearward by return springs 30 and 30 # interposed between the springs.

On the other hand, an eraser holder 40 having an eraser 45 fixed thereto is fitted in a cylindrical portion having a slit 37,
The inner cylindrical portion 35 of the crown 34 is fitted into the inner hole of the cap 4 in a state where the inner cylindrical portion 35 is fitted on the cylindrical portion of the cylindrical cam 5, and the crown 34 is fixed to the cap 4 so as to be rotatable only. At this time, the projection 42 of the eraser holder 40 is elastically fitted into the spiral groove 36. (In order to fit the projection 42 into the spiral groove 36, there is an operation of fitting the crown 34 while rotating the crown 34 as appropriate.) As described above, when the outer cylindrical portion 34a of the crown is rotated left and right with respect to the cap 4, the rear end The eraser 45 protrudes from the hole 39.

In this state, the cylindrical cam 5 is inserted into the rear end hole of the central shaft 1 so that the projection 17 is elastically fitted into the circumferential groove 19, and is rotatable at 180 ° in the circumferential direction with respect to the central shaft 1. Stop and secure. In addition, mechanical pencil 7
Is protruded, the cap 4 can be shifted by the stroke necessary for centering the core 1 with respect to the center shaft 1, and when the writing body is stored or the writing body 8 such as a ballpoint pen projects,
Axis transition is made impossible. Since the sliding pieces 6, 6 # are constantly urged rearward by the return springs 30, 30 #, the cam slopes of the projections 22, 22 # are always kept in contact with the cam slope 14 of the cylindrical cam 5. ing.

The engaging portion 13 of the cylindrical portion 10 is elastically fitted in the engaging groove 12 of the front shaft 3 with the rear end surface of the front shaft 3 in contact with the front surface of the step portion 31 of the center shaft 1. Thus, the front shaft 3 and the center shaft 1 are fixed in a state where rotation is prevented and the shaft is prevented from coming off. The tip shaft 3 is detachable with an appropriate force. When the cap 4 is rotated in one direction with respect to the front shaft 3 or the center shaft 1 in this state, the sliding piece 6 advances, and the notch 15 at the foremost end of the cam slope 14 of the cylindrical cam 5 becomes one of the mechanical pencils 7. The writing tip is locked to the projection 22 of the sliding piece 6 so that the writing tip projects from the tip end of the front shaft. Further, when the cap 4 is rotated to the other end with respect to the front shaft 3 or the center shaft 1, the sliding piece 6 is retracted so that the writing tip of the mechanical pencil 7 penetrates from the tip of the leading shaft and the sliding piece 6 is moved.前進 moves forward, and the writing tip of the writing body 8 such as a ballpoint pen projects from the tip end of the front shaft.

FIGS. 3 and 4 show another example of the engagement between the projection 17 of the cylindrical cam and the central shaft 1 °. In this case, as means for fitting the projection 17 into the circumferential groove 60,
A partition wall 62 having an inclined surface 63 is provided on an upper wall of a guide groove 61 in which the projection 17 is fitted from the rear end of the central shaft 1 #.
The reason for providing the partition wall 62 is to enhance the rigidity of the center shaft 1 ° at the engaging portion.

[0019]

When the cap 4 is rotated in one direction with respect to the front shaft 3 or the center shaft 1, the cam slope 1 of the cylindrical cam 5 is rotated as shown in FIG.
A notch 15 provided at the front end of the pen 4 engages with the sliding piece 6 of one of the mechanical pencils 7 to protrude the writing end from the front end of the front shaft. At this time, the projection 17 of the cylindrical cam 5 is located in the wide groove 48 in the peripheral groove 19 of the center shaft 1. In this state, when the rear end of the crown 34 is knocked and the cylindrical cam 5 is shifted axially, the operation is transmitted to the sliding piece 6, the core pipe 23, and the mechanical pencil 7, and the step 28 of the writing tip is moved. From a state in which the chuck comes into contact with the inner step portion 27 of the front shaft 3, the chuck moves along with the joint 29 so that the core is extended. When the cap 4 is rotated to the other end with respect to the front shaft 3 or the center shaft 1, the mechanical pencil 7 retreats, and instead the writing tip of the writing pen 8 such as a ballpoint pen projects from the tip of the front spindle. In addition, when the cursive body is stored, when the cursive body such as a ballpoint pen protrudes,
The projection 17 is located in the narrow groove 49 of the peripheral groove 19, and the projection 17 does not abut on the front wall 51 of the peripheral groove 19 in a state where the wall 20 of the cap 4 abuts on the rear end of the center shaft 1 by knocking. Therefore, the projections and the like do not break. Next, when the outer cylindrical portion 34 a of the crown is rotated left and right with respect to the front of the cap 4, the eraser holder 40 moves back and forth, and the eraser 45 is inserted through the rear end hole 39.
Haunts.

[0020]

As described above, according to the present invention, a cylindrical portion having a slit is provided at the rear of a cylindrical cam, and a resin cap having an integrated cylindrical portion is provided outside the cylindrical portion. Conventionally, a crown made of resin with a spiral groove formed in the hole is fitted to the cap in a state of being fitted to the cylindrical part of the cylindrical cam, and the crown is fixed to the cap so that it can only rotate In contrast to the example, the metal is replaced with resin, the number of parts is omitted, the structure is simplified, the assembly is easy, and the cost is reduced. Further, according to the embodiment, the front shaft, the center shaft integrally provided with the guide portion is a resin molded product, and the protrusion provided on the side surface of the cylindrical cam is elastically fitted into the circumferential groove formed in the rear of the center shaft, In addition, since the central shaft is integrally provided with an engaging portion to be joined to the front shaft, the number of parts is reduced as compared with the conventional double-type writing instrument, the structure is simplified, and the assembly is facilitated and the cost is further reduced. Is achieved. Further, even when an impact such as a rear end drop is applied, the projection for locking the cylindrical cam and the central shaft does not abut against the front wall of the peripheral groove, thereby preventing a problem such as breakage.

[Brief description of the drawings]

FIG. 1 is a longitudinal cross-sectional view of an entire main part showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an engagement state between a projection of a cylindrical cam and a peripheral groove of a center shaft.

FIG. 3 is an explanatory view showing another example of an engagement state between a projection of a cylindrical cam and a peripheral groove of a center shaft.

FIG. 4 is a cross-sectional view of a main part of an engaging portion in FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Middle shaft 1 ２ Middle shaft 2 Guide cylinder 3 Front shaft 4 Cap 4a Cylindrical part 4b Shaft part 5 Cylindrical cam 6 Sliding piece 6 ｀ Sliding piece 7 Pencil writing body 8 Writing body such as ballpoint pen 9 Guide groove 9 ｀ Guide groove 10 cylinder Part 11 Knock spring 12 Engagement groove 13 Engagement part 14 Cam slope 15 Notch 16 Partition part 17 Projection 18 Vertical groove 19 Peripheral groove 20 Wall 21 Window 22 Projection 22 Projection 23 Core pipe 24 Flange part 25 Tail plug 26 Locking part 27 inner step part 28 step part 29 joint 30 return spring 30 リ タ ー ン return spring 31 step part 32 hole 32 hole 33 engaging part 34 crown 34a outer cylinder part 34b engaging part 35 inner cylinder part 36 spiral groove 37 slit 38 step Part 39 rear end hole 40 eraser holder 41 cylindrical part 42 protrusion 43 elastic piece 44 locking protrusion 45 eraser 46 inclined 47 Habasema portion 48 Habahiromizo 49 Habasemamizo 50a rear wall 50b inclined face 50c rear wall 51 front wall 60 peripheral groove 61 guide groove 62 partition wall 63 inclined surface

Claims (1)

(57) [Scope of request for utility model registration] A guide provided integrally with an inner bore of a center shaft, wherein an engagement portion is provided for fitting the front end of the resin shaft and the front end of the resin center shaft in a non-rotatable and non-removable state. A return spring is provided between the guide piece and the sliding piece provided with a cursive writing at the rear end of each of the plurality of guide grooves of the section, and is urged rearward, and is fitted so as to be movable back and forth, and is displaced in the axial direction. A cylindrical cam with a circumferentially provided cam slope at the front end is rotatably retained with respect to the center shaft, and each sliding piece is brought into contact with the cam slope to alternate with the rotation of the cylindrical cam with respect to the front shaft or center shaft. In the compound writing tool, the tip of each writing body can be selectively protruded and retracted from the front end of the front shaft by moving back and forth, at least one of them is a mechanical pencil writing body, and the cylindrical cam shifts with respect to the center axis. The core can be extended, and A slit 37 is provided behind the cylindrical cam 5.
And a resin cap 4 integrally formed on the outside thereof.
And a crown 34 made of resin, and an outer cylindrical portion 34
a and an inner cylinder portion 35 is provided forward from the inside thereof, a spiral groove 36 is formed in an inner hole portion of the inner cylinder portion 35, and a cylinder portion of the cylindrical cam 5 is covered in an inner hole in the rear of the cap 4. The inner cylindrical portion 35 of the crown is fitted in the fitted state, and the crown 34 is attached to the cap 4.
Is fixed so as to be rotatable only. Further, an eraser holder 40 having an elastic portion for sandwiching an eraser 45 in the cylindrical portion of the cylindrical cam 5 and a projection 42 on the front cylindrical portion 41 is formed by the projection 42 with the slit 37 and the spiral groove. When the cap 4 is rotated with respect to the front shaft 3 or the center shaft 1, the tip of the cursive character appears and disappears, and the outer cylindrical portion 34 a of the crown 34 is rotated with respect to the cap 4. A double-type writing instrument characterized in that the eraser 45 is configured to be able to appear and disappear.