JP2003145990A - Duplex writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem hard to use because knocking force for delivering the lead of a propelling pencil writing body is too strong and a problem bitten in the lead to be easy to generate the breakage of the lead, in a duplex writing utensil. SOLUTION: The propelling pencil writing body 7 is constituted so that a head comes into contact with the front end of a rear shaft joint through a clamp, and a lead pipe joint is fastened to the rear end of a rear end chuck of which the rear part is provided so as to pierce through the axial center of the rear shaft joint through a first spring so as to draw the rear end chuck rearwardly. A holding chuck is provided to the front of the inner hole part of a front shaft joint, the rear end of a leading end chuck is fastened to the front hole of the front shaft joint in front of the holding chuck, a tip element is arranged to the rear of the head of the leading end chuck, a second spring is laid between the rear end of the tip element and the front shaft joint, the leading end chuck is energized so as to be tightened, and the front shaft joint is fixed to the front end of the rear shaft joint.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided writing instrument in which a mechanical pencil or a plurality of cursive bodies, at least one of which is a mechanical pencil cursive body, is mounted so that a writing tip can be selectively projected and retracted from an axis. Regarding

[0002]

2. Description of the Related Art Conventionally, mechanical pencils and at least one
2. Description of the Related Art There is known a double-sided writing instrument that is equipped with a plurality of writing bodies, each of which is a mechanical pencil writing body, and can selectively project and retract the writing tip portion from an axis. Further, a writing instrument in which an eraser feeding device is connected to the rear end of the multiple writing instrument is also known. As an example of such an eraser feeding device, the eraser can be retracted from the rear end by rotating the shaft cylinder of the eraser feeding device or the crown provided at the rear end of the shaft cylinder with respect to the connected writing instrument portion. By arranging a slit in the axial direction on the side surface of the shaft cylinder and the thing, and sliding the slider provided through the slit along the slit, the eraser holder integrated with the slider is moved back and forth. In some cases, the eraser fixed to the eraser holder appears and disappears from the rear end of the barrel.

In a conventional mechanical pencil, the front end of the lead penetrates the holding chuck and projects from the tip pipe, and the rear end of the lead is in front of the chuck. When is advanced, the following core moves forward while being held by the chuck. When the fastener is further advanced, the fastener comes into contact with the inner step portion provided on the base and only the chuck advances, so that the grasping of the lead is released and the front end of the lead comes into contact with the rear end of the residual lead. When the knock is released from that state, the chuck retracts with the core stopped, but from the time when the grip portion of the chuck starts to engage with the fastener, frictionally engages with the core,
Grasping is completed with the wick slightly retracted. That is, when the trailing end of the residual lead comes off the chuck grip, the leading end of the trailing lead contacts the trailing end of the remaining lead at the next knock, but the leading end of the trailing lead is not engaged with the holding chuck. , When the chuck is retracted, the chuck is tightened with fasteners, and the lead engages with the chuck slightly before, causing the lead to retract slightly,
A gap is created between the rear end of the residual core and the subsequent core. Therefore, when a writing pressure is applied to the front end of the residual core, core diving occurs due to the gap. When that happens, the writing feel is poor, and for a while the core dive is repeated with each knock. Therefore, usually, knocking is repeated and the remaining lead is often discharged.
In that case, there is a problem that the length between the front end of the chuck gripping portion and the front end of the tip pipe is wasted as a residual core. The length is different depending on the design, but is usually about 7 mm to 12 mm. Further, even if the patient is used with patience, when the rear end of the residual core advances to a position where it is separated from the holding chuck, the core falls off from the front end of the distal end pipe.

As a means for solving the problem, a mouth portion is provided at the front end of the shaft cylinder, a core case is provided inside the shaft cylinder, and a rear end chuck in which a fastener is fitted to the outer periphery of the grip portion at the front end part of the core case is a spring. The front end chuck is provided in front of the rear end chuck so as to interlock with a joint, and the gripping part of the front end chuck is engaged with the front end hole of the tip part to grip the core. There is known a mechanical pencil called a tip chuck or a double chuck configured as described above. In this case, the tip chuck can hold a residual core having a length of about 1 mm, and the core is not wasted.

By the way, the mechanical pencil writing body mounted on the conventional compound writing instrument has a structure in which the above-mentioned residual core is wasted. Also, the mechanical pencil cursive is
The core pipe is detachably attached to the front end of the core pipe, and the rear end of the core pipe is provided with a portion interlocking with a mechanism portion for selectively projecting and retracting the writing tip from the tip of the shaft, like other writing bodies.
Further, the feeding of the lead is performed by moving the lead pipe back and forth with the step portion of the mouthpiece abutting the inner step portion of the shaft tip.
Also, since the rear end of the lead pipe is restrained to the rear side, when the writing pressure is applied to the writing tip, the chuck receives a reaction force to the opening side, and the lead slips on the gripping part of the chuck. There is a problem of immersion. Therefore, the spring is strengthened to increase the gripping force, and the inner surface of the gripping part of the chuck is screwed to prevent the core from slipping, but the knocking force for feeding the core is too strong and the gripping force is difficult. Is too strong to bite into the core and cause core breakage.
In addition, another pipe is provided on the outside of the core pipe, and a mechanical pencil writing body can be attached to and detached from the front end of the pipe.
There is also a structure in which a part interlocking with the mechanical part is provided at the rear end of the pipe so that the reaction force is not applied to the rear end of the core pipe, but there is a problem that the structure becomes complicated and the cost increases significantly. . In addition, compared to the black sharp core, the other colored cores are softer, so problems such as core slippage and core breakage are more likely to occur.

As a sharp core, there is known a colored sharp core in which a porous burning core is impregnated with a dye or pigment ink without using a wax or the like, and a writing line can be easily erased with an eraser.

Further, as a ballpoint pen writing material, an ink having a relatively low viscosity is filled with a water-based ink having a so-called shear thinning viscosity, in which the viscosity is further reduced by the rotation of the tip ball and the ink smoothly flows out. Known ballpoint pens and ballpoint pens filled with low-viscosity oil-based ink are known. In such a ballpoint pen, when the ink on the back surface of the tip ball is exhausted when writing upwards, the head of the ink is directly applied, so that a remarkable backflow occurs and there is a risk of soiling hands and clothes.
Further, since the viscosity of the ink is low and the amount of outflow is large, there is a problem that the ink bleeds (DC) when a gap is formed between the tip ball and the tip holding portion when the tip side is faced down. Therefore, a follower that suppresses backflow of ink is provided at the rear end of the ink, and a means for pressing the back surface of the front end ball with a spring so that the front end ball closely contacts the ball holding portion of the chip and a ball at the rear end of the chip. The means etc. which provide the valve chamber which loosely fitted the valve are used. There is also known an erasable ink which includes a rubber latex and an adhesive resin particle and has a shear thinning property.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a plurality of mechanical pencil writing bodies or a multiple writing instrument equipped with a plurality of writing bodies, at least one of which is a mechanical pencil writing body. In addition to solving the problems that exist in the above, the drawing line can be easily erased with an eraser.Providing a convenient compound writing instrument that uses a colored sharp core or a ballpoint pen that uses ink that can be erased with an eraser, and an eraser feeding device is integrated. The purpose is to provide easy-to-use compound writing instruments in preparation for.

[0009]

The present invention has the following constitution in order to achieve the above object. The compound writing instrument according to the invention of claim 1 is provided with a plurality of mechanical pencil writing bodies or a plurality of writing bodies having at least one mechanical pencil writing body mounted in the shaft, and the tip of each writing body is a tip of the tip. In a compound writing instrument capable of selectively appearing and retracting from an end opening, the mechanical pencil writing instrument has its head contacting the front end of the rear axle joint via a fastener, and the rear portion penetrates the axial center of the rear axle joint. At the rear end of the rear end chuck provided by
The core pipe joint is fixed so as to pull the rear end chuck backward through the spring of the front end, while the holding chuck is provided in front of the inner hole of the front end joint, and the front end of the front end joint is located in front of the holding chuck. The rear end of the tip chuck is fixed to the hole, and a tip is disposed behind the head of the tip chuck, and a second end is provided between the rear end of the tip and the front shaft joint.
The spring is laid, is urged so that the tip chuck is tightened, and the front shaft joint is fixed to the front end of the rear shaft joint.

According to a second aspect of the present invention, there is provided the compound writing instrument according to the first aspect, wherein the front shaft joint is detachably attached to the front end of the rear shaft joint of the mechanical pencil writing body. Characterize.

A compound writing instrument according to a third aspect of the present invention is the compound writing instrument according to the first aspect, wherein a guide pipe is provided so as to cover the front shaft joint of the mechanical pencil writing body and the outer peripheral portion of the tip. The guide pipe is fixed to one of the front shaft joint and the tip, and the other is slidable on the inner surface of the guide pipe.

A compound writing instrument according to a fourth aspect of the present invention is the compound writing instrument according to the first aspect of the present invention, in which the outer peripheral portion of the rear axle joint and the core pipe joint is covered in the mechanical pencil writing body. A guide pipe is provided, the guide pipe is fixed to the rear shaft joint, and the core pipe joint is slidable on the inner surface of the guide pipe.

A compound writing instrument according to a fifth aspect of the present invention is the compound writing instrument according to the first aspect of the present invention, in which a colored sharp core or an eraser-erasable ink whose writing line can be easily erased with an eraser is used. It is equipped with the ballpoint pen cursive used.

The compound writing instrument according to a sixth aspect of the present invention is the compound writing instrument according to the first aspect, wherein the rear end is integrally provided with an eraser feeding device.

[0015]

EXAMPLE The writing instrument body of the present invention can be applied to the writing instrument body of the conventionally known compound writing instrument (with the writing body removed). As an example, a plurality of writing bodies fixed to a plurality of knock operating parts in a shaft can be slidable along vertical grooves provided in the shaft, and the tip of one writing body can be selectively moved from the tip of the shaft. 2. Description of the Related Art There is a multiple writing instrument that is projected and engaged, and when each of them is projected, the other writing bodies are disengaged to be housed in a shaft by the action of a return spring.

Further, the front shaft and the front end of the guide cylinder are fixed, and a plurality of writing bodies having a sliding end fixed to the rear end are provided in a plurality of guide grooves provided in the guide cylinder. A return cam is urged in between, and a cylindrical cam having a cam slant surface that is axially movably fitted to each other and that has a cam slant surface that is displaced in the axial direction is provided so as to be rotatable and axially shiftable with respect to the guide cylinder. , The sliding pieces are alternately moved back and forth by the rotation of the cylindrical cam by bringing the respective sliding pieces into contact with the cam slope.
There is a compound writing instrument in which the tip of each writing body can be selectively retracted from the tip of the shaft.

Furthermore, a plurality of cursive bodies are included, and
A hollow cylindrical body extending from a protruding front end portion to a rear end portion of an arbitrary cursive body, and enclosing the rear portion of the cylindrical body, and being movable back and forth along the longitudinal direction of the cylindrical body. And a knocking body, which is swingably supported by the rear portion of the knocking body, and which advances any knocking body to cause any one of the plurality of writing bodies to protrude from the front end portion of the cylindrical body (writing body selecting portion (selected writing body). Method of contacting the tip of the pendulum with its own weight on the rear end of the body side)
There is also a double-sided writing instrument having a writing state maintaining section for maintaining the protruding state of the arbitrary writing body and a writing body immersing section for immersing the protruding writing body.

Further, the mechanical pencil writing body mounted on the various writing instruments as described above has a mounting portion (core pipe joint) at the rear end, and the core is provided on the core pipe provided in the writing instrument main body. While being replenished, the mounting portion is removably mounted on the front end of the core pipe.

The compound writing instrument shown as the embodiment of the present invention is characterized in that the eraser feeding device is integrally connected to the rear portion of the writing mechanism. First, Fig. 1
The embodiment shown in (1) shows a compound writing instrument equipped with two types of writing materials, including a center shaft 1, a tip shaft 3, and a guide unit 2 integrally provided.
An eraser feeding device 4 integrally provided with a cylindrical cam 5, a pair of sliding pieces 6a, 6b, a mechanical pencil writing body 7,
The ballpoint pen cursive body 8 is a main component.

The center shaft 1 is made of resin, and is provided with a guide groove 2a which is long in the axial direction and which is open to the side surface from the substantially central portion to the rear end, and a guide portion 2 having a similar guide groove 2b on the side surface opposite to the guide groove 2a. There is. The guide portion has two guide grooves formed on the cylindrical portion standing in the inner hole of the center shaft or ribs on the wall of the inner hole of the center shaft so that the sliding piece to be described later can be guided in the axial direction. It is provided. Further, the front half of the guide portion 2 is provided with a tubular portion 9 having a partition portion 15 communicating with the respective guide grooves 2a and 2b and having holes 15a and 15b and having a front end opened. The stepped portion 31 has a stepped portion 31, and a bulging engagement portion 10 is formed on the front outer peripheral portion of the stepped portion 31.

Further, as shown in FIG. 3, a vertical groove 17 is formed on the rear side surface of the center shaft 1 with a narrow portion 17b via a forward inclined surface 17a.
Is connected to the circumferential groove 18 and a substantially inverted T-shaped window portion is bored. As will be described later, the projection 16 of the cylindrical cam 5 has a vertical groove 18
Then, the protrusion 16 elastically expands the inclined surface 17a, passes through the narrow portion 17b, and enters the circumferential groove 18. The cylindrical cam 5 rotates within a range in which the projection 16 abuts on both walls in the circumferential direction of the circumferential groove 18, so that the writing parts of the mechanical pencil writing body 7 or the writing body 8 such as a ballpoint pen are alternately projected and retracted from the tip end opening of the tip shaft. become. Further, the circumferential groove 18 is a mechanical pencil cursive body 7.
A wide knock groove 19 is provided so that the cylindrical cam 5 can be axially moved at the position of the protrusion 16 when the handwriting protrudes, and the position of the protrusion 16 when the handwriting body is stored or the handwriting body 8 such as a ballpoint pen protrudes. Thus, a narrow groove 18c is provided between the rear wall 18b and the front wall 18a of the circumferential groove 18 so that the cylindrical cam 5 cannot move substantially along the axis. Various means have been disclosed that are not limited to the above, as means for locking and retaining the cylindrical cam so that it can rotate with respect to the center shaft within a certain range.

The front end of the front shaft 3 is tapered, and the front end of the inner hole is provided with an inner step portion 27. Further, the rear end hole is provided with an engaging groove 12 which is engaged with an engaging portion 10 provided on the outer peripheral portion of the tubular portion 9 of the guide tube and which prevents the tubular portion 9 from coming off and is prevented from rotating. . The tubular portion 9 and the tip shaft 3
Is detachably fixed with an appropriate force.

The eraser feeding device 4 includes a barrel 4a, eraser holders 37 and 38 of the same shape, and a slider 4 of the same shape.
0, 41, and erasers 42a, 42b of the same shape. The shaft cylinder 4a is made of resin and integrally has a cylindrical cam 5 at its tip. The cylindrical cam 5 has a cylindrical shape, has a cam slope 13 that is circumferentially displaced forward and backward at the front edge, and a notch 14 is formed at the forefront end of the cam slope 13.
In addition, the side surface of the cylindrical cam 5 is inserted into the vertical groove 18 of the center shaft 1 and elastically fits into the circumferential groove 18, and a predetermined range (approximately 180).
The protrusion 16 is formed so as to rotate and prevent it from coming off.

By the way, a cylindrical cam 5 is provided at the front end of the shaft cylinder 4a.
Is formed, and slits 32 are provided in the axial direction at two opposing positions on the side surface of the shaft cylinder 4a. The slit 32 has a narrow vertical groove 3 formed to reach the rear end in the longitudinal direction.
3 and the vertical grooves 33 thereof are provided with slightly wide lateral grooves 34 which are provided at appropriate intervals.

Further, the eraser holder 37 (see FIGS. 4 and 5) is provided with a hole having a groove 37c opened at the front end and a locking step 37d at the rear end of the groove on the side surface of the piece 39 at the front end. On the other hand, the plate-like slider 40 is provided with a rib 40a standing upright toward the lower surface at the rear end thereof, and the engaging portion 40c of the rib 40a is formed on the locking step portion 3.
7d by utilizing elastic displacement, and integrally with the slider 40 on the rear end side surface of the piece 39 with the rib 40a as a support shaft.
Are fixed in parallel to the rear of the eraser holder 37. A locking projection 39a is formed on the piece 39 at a position appropriately rearward of the rib 40a. Also, the cylinder 4
When the slider 40 is pressed inward of a, the locking projection 3
9a is displaced inward. Also, a rib 37 is provided at the rear end of the piece 39.
A fastening portion 37a surrounded by b is provided, and an eraser 42a is fixed to the fastening portion 37a.

As described above, the eraser holders 37 and 38 are inserted from the rear end of the shaft cylinder 4a, the ribs 40a of the sliders 40 and 41 are fitted from the outside into the vertical grooves 33 of the slit 32, and the locking projections 39a are slit. The sliders 40, 41 that are elastically disengageable in the lateral groove 34 of the shaft 40 and that are provided so as to extend through the slit 32 slide in the front-rear direction along the slits so that the sliders 40, 41 interlock with the sliders inside the barrel 4a. Eraser holders 37 and 3 provided on the
By moving 8 back and forth, the rear end of the eraser fixed to the eraser holder can be retracted from the rear end of the barrel.

In order for the slider 40 to slide smoothly, it is necessary to make the width of the rib 40a larger than the width of the lateral groove 34 in the axial direction to prevent the rib from engaging with the lateral groove. However, if the rib 40a is small for the convenience of design, it can be solved by providing a detent between the inner surface of the shaft cylinder and the outer periphery of the cylinder portion of the eraser holder. 6 and 7
Shows another embodiment of the slider in which the rib 43a is provided between the rib 40a and the locking projection 43, and this may also be used.

On the other hand, the sliding piece 6a has a protrusion 22a on its outer surface, and a central portion projects from the rear end face of the protrusion 22a, and both sides of the protrusion are substantially the same slope as the cam slope 13 of the cylindrical cam 5 described above. have. Further, there is provided a hole that abuts on the flange portion 24 of the core pipe 23 and projects and fits behind the core pipe 23 for a long time. Similar to the sliding piece 6a, the sliding piece 6b has a protrusion 22b and a cam slope, and a locking portion 26 for fixing the rear end of the writing body 8 such as a ballpoint pen is provided at the tip. The locking portion may be formed in a pipe shape and the rear end of the writing body may be fitted therein.

On the other hand, as shown in FIG. 2, in the mechanical pencil writing body 7, the head comes into contact with the front end of the rear shaft joint 7e via the fastener 7h, and the rear part penetrates the shaft center of the rear shaft joint 7e. The core pipe joint 29 is fixed to the rear end of the rear end chuck 7b provided so as to pull the rear end chuck 7b rearward through the first spring 7g, while the inner pipe portion of the front shaft joint 7d is fixed. A holding chuck 7c made of an elastic material such as rubber is provided in front of the holding chuck 7c. The rear end of the tip chuck 7a is fixed to the front end hole of the front shaft joint 7d in front of the holding chuck 7c, and the head of the tip chuck 7a is fixed. Tip 7 behind the section
i is disposed, and the rear end of the tip 7i and the front shaft joint 7
The second spring 7 is provided between the step and the step provided in front of d.
f is laid and biased so that the tip chuck 7a is tightened. The holding chuck 7c can be integrally formed in a shape that allows elastic displacement when the front shaft joint 7d is a resin molded product having excellent elasticity.

A guide pipe 11b made of thin-walled metal is provided to cover the outer circumferences of the front shaft joint 7d and the tip 7i, and the rear of the guide pipe 11b is fixed to the outer peripheral portion of the front shaft joint 7d. 11b on the front inner surface of 11b
The outer peripheral portion of i is slidably and closely attached. The guide pipe 11b can be fixed to either one of the front shaft joint 7d and the tip 7i, and the other can be slidable on the inner surface of the guide pipe. A guide pipe 11a is provided so as to cover the outer peripheral portions of the rear shaft joint 7e and the core pipe joint 29.
Is fixed to the outer peripheral portion of the rear shaft joint 7e, and the rear outer peripheral portion of the core pipe joint 29 is slidably and closely attached to the rear inner surface of the guide pipe 11a.

Further, the screw portion provided on the outer periphery of the front end of the rear shaft joint 7e and the screw portion provided in the rear end hole of the front shaft joint 7d are screwed to each other, so that the rear shaft joint 7e and the front shaft joint 7d are attached and detached. Fixed as possible. The rear shaft joint and the front shaft joint may be fixed to each other by press fitting or the like. Further, it can be detachable by an engaging means other than screwing.

As described above, the mechanical pencil writing body 7 is joined to the core pipe 23, and the sliding piece 6a is fitted by abutting on the flange portion 24 provided at the rear of the core pipe 23, and the rear end of the sliding piece 6a. The rear end hole of the core pipe 23 protruding from is closed by a tail plug 25 or the like. The lead-out is performed by moving the trailing end chuck 7b by the axial transition of the sliding piece 6a while the step 28 provided on the tip 7i of the mechanical pencil writing body 7 is in contact with the inner step 27 of the tip shaft 3. This is performed by operating the tip chuck 7a.

Explaining in the order of assembling, the mechanical pencil writing body 7 and the ballpoint pen writing body 8 are connected to the respective sliding pieces 6a and 6b at the rear ends thereof to form the guide grooves of the guide portion 2 of the center shaft. 2a and 2b are movably fitted,
A return spring 3 interposed between the front end surface of each sliding piece 6a, 6b and the partition portion 15 on the front surface of the guide groove 2a, 2b.
It is urged rearward by 0a and 30b. The eraser feeding device 4 inserts the cylindrical cam 5 into the rear end hole of the center shaft 1 and elastically fits the protrusion 16 into the circumferential groove 18, and is rotatable about 180 degrees in the circumferential direction with respect to the center shaft 1. It keeps coming off and is fastened. Further, the eraser feeding device 4 is configured to be capable of shifting the stroke by the stroke required for feeding the core with respect to the center shaft 1 in a state where the mechanical pencil writing body 7 is projected, and when the writing body is stored or the writing body 8 such as a ballpoint pen is projected. In this state, the axis transition is impossible. Since the sliding pieces 6a, 6b are always urged rearward by the return springs 30a, 30b, the cam slopes of the protrusions 22a, 22b are always kept in contact with the cam slope 13 of the cylindrical cam 5.

Further, with the rear end surface of the front shaft 3 in contact with the front surface of the stepped portion 31 of the center shaft 1, the engaging portion 10 of the tubular portion 9 is elastically fitted in the engagement groove 12 of the front shaft 3. As a result, the front shaft 3 and the center shaft 1 are fixed in a rotation-stopping and slip-out preventing state. The front axle 3 can be attached and detached with an appropriate force. In this state, when the barrel 4a is rotated to one side with respect to the front shaft 3 or the center shaft 1, the sliding piece 6a is rotated.
Moves forward and the notch 1 at the front end of the cam slope 13 of the cylindrical cam 5
4 is locked to the projection 22a of the sliding piece 6a of the one mechanical pencil writing body 7, and the writing tip portion is projected from the tip shaft tip opening. Further, when the shaft cylinder 4a is rotated to the other side with respect to the front shaft 3 or the center shaft 1, the sliding piece 6a retracts and the writing tip portion of the mechanical pencil writing body 7 is retracted from the tip end opening of the leading shaft, and at the same time, the sliding piece is moved. 6b advances, and the writing tip portion of the other ball-point pen writing body 8 projects from the tip end tip opening.

On the other hand, the eraser feeding device 4 includes the barrel 4
Insert the eraser holders 37 and 38 from the rear end of a,
The sliders 40 and 41 are attached to the eraser holders 37 and 38, the locking projection 39a is elastically engaged with the lateral groove 34 of the slit 32 provided in the shaft cylinder, and the slider 40,
Eraser holders 37 and 38 are slidable with respect to the barrel through 41. Erasers 42a and 42b
Are inserted through the opening 36 at the rear end of the shaft cylinder, and the front end of each eraser is fixed to the fastening portion of the eraser holder.

FIG. 10 shows a BB cross section of FIG. As shown in the figure, a rib-shaped guide protrusion 4b is provided along the axial direction on the inner surface of the shaft cylinder 4a, so that even if one of the eraser and the eraser holder moves back and forth independently. There is no rattling problem.

FIG. 11 shows a state corresponding to FIG. 10 when three or more cursive bodies are mounted. The basic structure is the same as in the case of FIG.

[0038]

When the shaft cylinder 4a is rotated to one side with respect to the front shaft 3 or the center shaft 1, the cam slope 13 of the cylindrical cam 5 is rotated as shown in FIG.
The notch 14 provided at the tip of the writing element engages with the sliding piece 6a of the one mechanical pencil writing body 7 to project the writing tip portion from the tip end opening. At this time, the protrusion 16 of the cylindrical cam 5 is located in the knock groove 19 of the circumferential groove 18 of the center shaft 1. In this state, if the rear end of the shaft cylinder is knocked and the cylindrical cam 5 moves axially,
The motion is transmitted to the sliding piece 6a, the core pipe 23, and the mechanical pencil writing body 7, and the step portion 28 of the tip tool 7i causes the tip shaft 3 to move.
From the state where it abuts the inner step portion 27 of the core pipe joint 29
With the transition of the axis, the rear end chuck 7b and the front end chuck 7a are actuated to feed the lead. When the barrel 4a is rotated to the other side with respect to the tip shaft 3 or the center rod 1, the mechanical pencil writing body 7 is retracted, and instead, the writing tip portion of the ballpoint pen writing body 8 projects from the leading tip end opening.

By the way, when the lead pipe joint 29 is advanced a little from the state in which the step portion 28 of the tip tool 7i is in contact with the inner step portion 27 of the tip shaft 3 (see FIG. 2), the tip tool 7i is moved to the tip tool 7i. The tip chuck 7a is advanced and opened, and the lead grip is released. That is, the spring force of the first spring 7g for urging the rear end chuck 7b rearward is appropriately set stronger than the spring force of the second spring 7f for urging the front end chuck 7a rearward. Further, the advancement of the tip chuck is stopped in a state where the core grip of the tip chuck is released. Although there are some means for this method, in the embodiment, the guide pipe 11b is provided so that the front end of the guide pipe 11b abuts against the inner step portion of the front end of the front shaft 3 and is stopped. Therefore, when the lead pipe joint 29 is further advanced, the trailing end chuck 7b is started and the lead is fed from the leading end of the leading end chuck 7a.

Then, as another means for stopping the tip chuck 7a, a stopper ring is provided at the rear portion of the tip chuck so that the tip tool 7i is properly advanced in a state where the tip chuck is advanced.
Abut on the rear end. In addition, the second spring is set to the pre-compression state with the tip chuck appropriately advanced. Further, a flange portion is formed behind the stepped portion 28 of the tip 7i, and the front end of the guide pipe 11b is brought into contact with the rear end of the flange portion in a state where the front end chuck has appropriately advanced. Further, the front part of the guide pipe 11b is fixed to the tip tool, the rear part of the guide pipe is slidably fitted on the outer periphery of the front shaft joint 7d, and the rear end of the guide pipe is moved forward with the tip chuck appropriately advanced. It is provided so as to come into contact with the flange portion provided at the rear end of the joint. There are several means, etc.

Further, as in the conventional case, since the rear end of the core pipe is restrained to the rear side, when the writing pressure is applied to the writing tip, the chuck receives a reaction force on the opening side.
Although the core grip of the rear end chuck 7b is released, the front chuck 7a is always clamped by the tip tool 7i and the core grip is maintained. Therefore, the core is the tip chuck 7a.
There is no slipping in of the grip part. Therefore, it is not necessary to strengthen the spring to increase the gripping force or to prevent the core slippage by forming a screw thread on the inner surface of the gripping portion of the chuck.

Next, when the slider 40 is retracted with respect to the shaft cylinder 4a, the locking projection 39a is moved to the lateral groove 3 of the slit 32.
4, the eraser holder 37 is gradually retracted, and the eraser 42a is fed out from the opening 36 at the rear end of the barrel. Also, the slider 40
When is pushed forward, the eraser holder 37 moves forward, and the eraser 42a sinks from the opening 36. Further, the slider 41 operates similarly.

By the way, a colored sharp core obtained by impregnating a porous burned core with a dye or pigment ink can have its writing lines easily erased with an eraser, but its erasability is not sufficient depending on the color. There is something. In addition, the eraser has the same color as the colored sharp core, and there is an advantage that stains on the eraser and the paper surface are not noticeable by using only the combination. Therefore, it is possible to substantially satisfy the erasability by preparing a dedicated eraser adapted to the color type of the colored sharp core. Similarly, if there is an ink that contains rubber latex or adhesive resin particles and has shear thinning properties and that can be erased with an eraser that does not have sufficient erasability depending on the color, the It is possible to satisfy the erasability by preparing an adapted special one.

[0044]

As described above, the present invention provides a multiple writing instrument with an eraser feeding device equipped with a plurality of mechanical pencil writing bodies or a plurality of writing bodies, at least one of which is a mechanical pencil writing body. The problem that the knocking force for unwinding is too strong and the gripping force is too strong and the gripping force is too strong to easily break into the core to break the core is solved, and the waste due to the residual core is eliminated. In particular, compared to the black sharp core, the other colored cores are softer, so problems such as core slippage and core breakage easily occur, and the effect is remarkable. Also, it is possible to provide a convenient compound writing instrument that uses a ballpoint pen that uses a colored sharp core that makes it easy to erase with a eraser and an ink that can be erased with an eraser.
It is possible to provide an easy-to-use compound writing instrument that is integrally provided with an eraser feeding device.

[Brief description of drawings]

FIG. 1 is a longitudinal cross-sectional view of an essential part of a writing instrument as a whole, showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a mechanical pencil writing body.

FIG. 3 is a view showing a joint relationship between a cylindrical cam and a center shaft.

FIG. 4 is a diagram of a main part showing a locking structure of a slider and an eraser holder.

FIG. 5 is a diagram of a main part corresponding to FIG.

FIG. 6 is a view of a main part showing another locking structure of a slider and an eraser holder.

FIG. 7 is a diagram of a main part corresponding to FIG. (A-A sectional view)

FIG. 8 is a top view showing the outer appearance of the main part behind the barrel.

FIG. 9 is a front view showing the outer appearance of the main part at the rear of the barrel.

10 is a sectional view taken along line BB of FIG.

FIG. 11 is a cross-sectional view showing a state corresponding to FIG. 10 when three or more cursive bodies are mounted.

[Explanation of symbols]

1 center axis 2 Guide section 2a Guide groove 2b Guide groove 3 tip axis 4 Eraser feeding device 4a shaft cylinder 4b Guide protrusion 5 Cylindrical cam 6a Sliding piece 6b Sliding piece 7 Mechanical pencil cursive 7a Tip chuck 7b Rear end chuck 7c holding chuck 7d Front axle joint 7e Rear axle joint 7f Second spring 7g first spring 7h fastener 7i tip 8 Ballpoint pen cursive 9 tube 10 Engagement part 11a Guide pipe 11b Guide pipe 12 engagement groove 13 Cam slope 14 notches 15 partition 15a hole 15b hole 16 protrusions 17 vertical groove 17a inclined surface 18 circumferential groove 18a front wall 18b rear wall 18c narrow groove 19 knock groove 20 walls 21 window 22a protrusion 22b protrusion 23 core pipe 24 Flange 25 tail plug 26 Locking part 27 Inner Step 28 steps 29 core pipe fitting 30a return spring 30b return spring 31 steps 32 slits 33 vertical groove 34 horizontal groove 35 locking step 36 openings 37 Eraser holder 37a Fastening part 37b rib 37c groove 37d locking step 38 Eraser holder 39 one side 39a Locking protrusion 40 slider 40a rib 40b protrusion 40c engaging part 41 Slider 42a eraser 42b eraser 43 Locking protrusion 43a rib 44 clips 45 shaft cylinder 45a guide protrusion 46a eraser holder 46b eraser holder 46c eraser holder 47a eraser 47b eraser 47c eraser 48 sharp core

Claims (6)

[Claims] 1. A plurality of mechanical pencil writing bodies or a plurality of writing bodies in which at least one is a mechanical pencil writing body is mounted in a shaft, and the tip of each writing body can be selectively retracted from a shaft tip opening. In the compound writing instrument described above, the mechanical pencil writing body is a rear end chuck in which the head contacts the front end of the rear axle joint via a fastener and the rear portion penetrates through the axis of the rear axle joint. A core pipe joint is fixed to the rear end of the rear end chuck so as to pull the rear end chuck rearward through the first spring, while a holding chuck is provided in front of the inner hole of the front shaft joint. The rear end of the tip chuck is fixed to the front end hole of the front shaft joint at the front, and the tip is disposed behind the head of the tip chuck, and between the rear end of the tip and the front shaft joint. The second spring is laid in Is energized so that the end chuck is tightened, multiplex writing implement, characterized in that the front shaft coupling the front end of the rear shaft coupling is configured fixed. 2. The double-sided writing instrument according to claim 1, wherein in the mechanical pencil writing instrument, the front shaft joint is detachably attached to the front end of the rear shaft joint. 3. In a mechanical pencil writing instrument, a guide pipe is provided by covering the outer peripheral portions of the front shaft joint and the tip tool, and the guide pipe is fixed to either one of the front shaft joint and the tip tool. The dual writing instrument according to claim 1, wherein the other is slidable on the inner surface of the guide pipe. 4. A mechanical pencil writing instrument, wherein a guide pipe is provided by covering an outer peripheral portion of a rear shaft joint and a core pipe joint, the guide pipe is fixed to the rear shaft joint, and the core pipe joint is a guide pipe. The double-sided writing instrument according to claim 1, which is slidable on the inner surface of the writing instrument. 5. The double-sided writing instrument according to claim 1, further comprising a colored sharp core whose writing line can be easily erased with an eraser and a ballpoint pen writing body using an eraser-erasable ink. 6. The double-sided writing instrument according to claim 1, wherein an eraser feeding device is integrally provided at the rear end.