JP2020196209A - Magnetic writing instrument - Google Patents

Abstract

To provide a magnetic writing instrument that is more convenient for users.SOLUTION: A magnetic writing instrument 10 of the present invention has a function of drawing characters or the like on the magnetic sheet or erasing the drawn characters or the like by applying a magnetic field on the magnetic sheet, and includes a grip body 100, a bold writing portion 200 provided at one end of the grip body 100, and the fine writing portion 300 provided at the other end. The bold writing portion 200 includes a drawing portion 220 and an erasing portion 230, and the fine writing portion 300 includes a drawing portion 320 and an erasing portion 330. The drawing portions 230, 330 and the erasing portions 230, 330 each include a magnet. Moreover, the drawing portions 220 and 320 and the erasing portions 230 and 330 are separated from each other so as not to interfere with each other.SELECTED DRAWING: Figure 1

Description

According to the present invention, a magnetic field can be applied to a display sheet or magnetic panel including a magnetic display body to draw arbitrary characters, figures, symbols, etc., and to erase drawn characters, figures, symbols, etc. Regarding writing instruments.

By moving a magnetic pen with a magnet attached to the tip of a magnetic sheet containing a magnetic display, a magnetic field is applied on the magnetic sheet to draw characters, figures, symbols, etc. according to the movement trajectory. (Patent Document 1, etc.). In addition, the drawn characters, figures, and symbols can be erased by moving the magnetic erasing tool on the magnetic sheet (Patent Document 2, etc.).

Japanese Patent No. 6179788 Japanese Patent No. 6213886

The user needs to use a magnetic pen when drawing, and to switch to a magnetic erasing tool when erasing the drawn characters and the like, and such work is very complicated. In addition, there are some that have a magnetic drawing function on one pen tip of one writing instrument and an erasing function on the other pen tip, but even in this case, the pen tip of the writing instrument is 180 degrees at the time of drawing or erasing. It needs to be flipped, and this task is still complicated.

The present invention solves such a conventional problem, and an object of the present invention is to provide a magnetic writing instrument that is more convenient for the user.

The magnetic writing instrument according to the present invention has a function of drawing characters or the like on the magnetic sheet or erasing the drawn characters or the like by applying a magnetic field on the magnetic sheet, and includes a grip body and the above. It has a drawing portion and an erasing portion provided at at least one end of the grip body, the drawing portion and the erasing portion each include a magnet, and the drawing portion and the erasing portion do not interfere with each other. Are separated from each other.

In certain embodiments, the drawing section and the erasing section are rotatable with respect to the grip body. In certain embodiments, the drawing portion and the erasing portion are detachably attached to the grip body. In some embodiments, the grip body further comprises another set of drawing and erasing portions at the other end, the drawing and erasing portions provided at one end being for bold or fine print. The drawing and erasing sections provided at the other end are for fine or bold. In some embodiments, the angle between the drawing section and the erasing section is variable. In some embodiments, the drawing portion or the erasing portion projects from the opening of the grip body by a knock mechanism. In certain embodiments, the drawing unit or the erasing unit is removable from the body unit attached to the grip body.

According to the present invention, since the drawing portion and the erasing portion are provided at at least one end of the grip body, the user can use another pen as in the conventional case when drawing from drawing to erasing or from erasing to drawing. It is not necessary to switch to the pen or flip the end of the pen, which can improve convenience.

It is a schematic perspective view which shows the whole structure of the magnetic writing instrument which concerns on 1st Example of this invention. 2 (A) is a schematic cross-sectional view of the grip portion, FIG. 2 (B) is a plan view showing a writing portion for bold characters, and FIG. 2 (C) is a plan view showing a writing portion for fine characters. It is an example of the usage state of the magnetic writing instrument of the first embodiment of the present invention, FIG. 4 (A) is an example at the time of drawing, and FIG. 4 (B) is an example at the time of erasing. It is an example when the angle adjustment mechanism is mounted on the drawing part and the erasing part of the writing part of this embodiment, FIG. 3A is a front view of the writing part, and FIG. 3B is a schematic view of the writing part. It is a side view. It is a figure explaining the magnetic writing instrument which concerns on 2nd Example of this invention. It is a figure explaining the magnetic writing tool which concerns on 3rd Example of this invention, FIG. 6A is a schematic cross-sectional view of a grip body, FIG. 6B is a schematic cross-sectional view of a drawing portion for bold. 6 (C) is a schematic cross-sectional view of a drawing portion for fine characters, and FIG. 6 (D) is a schematic cross-sectional view of an erasing portion. It is a figure explaining the magnetic writing instrument which concerns on 4th Example of this invention. It is a figure explaining the magnetic writing instrument which concerns on 5th Example of this invention.

Next, an embodiment of the present invention will be described in detail with reference to the drawings. In a preferred embodiment of the present invention, the magnetic writing instrument is provided with a magnetic drawing unit and a magnetic erasing unit at at least one end, and by moving the magnetic drawing unit on the magnetic sheet, characters, figures, pictures, etc. are printed on the magnetic sheet. It is possible to draw, and by moving the magnetic erasing unit on the magnetic sheet, it is possible to erase the drawn characters and the like. It should be noted that each configuration shown in the figure described in the embodiment of the present invention is different from the actual size.

FIG. 1 is a schematic perspective view showing the entire magnetic writing instrument according to the embodiment of the present invention. The magnetic writing instrument 10 according to the present embodiment includes a pen-shaped cylindrical grip body 100, a bold writing part 200 attached to one end of the grip body 100, and a fine writing part attached to the other end. It is configured to include a writing unit 300. Here, the bold writing unit 200 and the fine writing unit 300 are attached to both ends of the grip body 100, but even if either the bold writing unit 200 or the fine writing unit 300 is attached. Good. Further, the bold writing unit 200 and the fine writing unit 300 can be detachably attached to the grip body 100.

FIG. 2 shows the details of the grip body 100, the bold writing unit 200, and the fine writing unit 300. The grip body 100 can have any shape as long as it can be gripped by the user, and may have a prismatic shape (for example, a triangular cross section, a quadrangle, or a polygonal cross section) in addition to the cylindrical shape. Further, the grip body 100 can be made of any material, for example, plastic or metal. Further, the grip body 100 may have a uniform thickness as shown in FIG. 2 (A), and may not have a uniform thickness as shown in FIG. 2 (B), for example, an end portion. A taper may be formed so as to taper toward. Further, the outer shape of the grip body 100 may be formed with concave portions or convex portions that facilitate gripping.

In one example, the inside of the grip body 100 is hollow, the bold writing section 200 is inserted into the opening 110 at one end, and the fine writing section 300 is inserted into the opening 112 at the other end. To. The bold writing section 200 and the fine writing section 300 are inserted into the openings 110 and 112.

As shown in FIG. 2B, the bold writing unit 200 includes a columnar main body 210 inserted into the opening 110 of the grip main body 100, and a drawing unit 220 and an erasing unit 230 connected to the main body 210. And have. As described above, the main body 210 has a diameter slightly larger than the diameter of the opening 110, and is fitted into the opening 110 so as to be removable.

The drawing unit 220 has a connecting portion 222 connected to the shaft 212 of the main body portion 210, a cylindrical holder 224 attached to the end portion of the connecting portion 222, and a magnet 226 held in the holder 224. The holder 224 is made of a magnetic and / or non-magnetic material. A portion of the holder 224 projects from the connecting portion 222, and the protruding flat end surface provides a sliding surface with respect to the magnetic sheet S. The magnet 226 is fixed at a predetermined distance from the end face of the holder 224, and when the holder 224 is slid on the magnetic sheet, an appropriate magnetic field is applied to the magnetic sheet to enable drawing of characters and the like.

The erasing unit 230 includes a connecting portion 232 connected to the shaft 212 of the main body portion 210, a cylindrical holder 234 attached to the end of the connecting portion, a magnet 236 held in the holder 234, and a holder 234. It has a magnetic force adjusting ring 238 that can move in the axial direction. In one example, the drawing unit 220 and the erasing unit 230 are fixed to the grip body 100 at a predetermined angle. In another example, the drawing unit 220 and the erasing unit 230 can be adjusted to a selected angle with respect to the grip body 100. For example, by rotating the shaft 212, the relative angles of the drawing unit 220 and the erasing unit 230 with respect to the main body unit 210 are changed. As will be described later, the user rotates the grip body 100 approximately half a turn (rotates about 180 degrees around the axis of the grip body) to maintain the posture in which the grip body 100 is tilted with respect to the magnetic sheet S. The axial direction of the drawing unit 220 or the erasing unit 230 is substantially orthogonal to the plane of the magnetic sheet S.

A part of the holder 234 protrudes from the connecting portion 232, and the protruding end face is curved in a dome shape, for example. There are individual differences in the angle at which the grip body 100 is tilted with respect to the magnetic sheet S, and by bending the end face of the holder 234, the magnetic sheet does not necessarily have an axial direction of the holder 234 orthogonal to the plane of the magnetic sheet S. Sliding on S becomes easy.

The magnet 236 is fixed at a predetermined distance from the end face of the holder 234, and when the holder 234 is slid on the magnetic sheet, an appropriate magnetic field is applied to the magnetic sheet to erase characters and the like. The magnetic force adjusting ring 238 is made of a magnetic material, and by moving its position, the strength and direction of the magnetic force lines of the magnet 234 are adjusted. For example, if the magnetic force adjusting ring 238 is moved to the magnetic sheet side, the spread of the magnetic force lines of the magnet 236 is suppressed, and the magnetic force lines can be concentrated in a relatively narrow range. On the contrary, if the magnetic force lines are moved away from the magnetic sheet side, the magnet The 236 lines of magnetic force spread laterally, and the lines of magnetic force can be diffused over a relatively wide range. From such a magnetic force adjusting ring 238, it is easy to erase by changing the erasing area on the magnetic sheet or changing the magnetic force for characters and the like that are difficult to erase.

The configuration of the writing unit 300 for fine characters is shown in FIG. 2 (C). The fine writing unit 300 includes a main body 310, a drawing unit 320, and an erasing unit 330, which are substantially the same as those of the bold writing unit 200, and thus detailed description thereof will be omitted. However, in the writing unit 300 for fine characters, the holder 324 and the magnet 326 of the drawing unit 320 and the holder 334 and the magnet 336 of the erasing unit 330 are relatively smaller in size than those of the writing unit 200 for bold characters. As a result, the range covered by the magnetic force of the magnets 326 and 336 is limited, and it is possible to draw fine characters and the like on the magnetic sheet and erase small parts as compared with the writing unit 200 for bold characters. .. In the following description, a bold writing instrument 200 will be used as a typical example.

Next, an example of using the magnetic writing instrument of this embodiment is shown in FIG. FIG. 3A shows a state when characters and the like are drawn on the magnetic sheet S by the drawing unit 220 of the bold writing unit 200. The angle of the drawing portion 220 with respect to the grip body 100 is preset so that the flat end surface of the holder 224 is substantially parallel to the magnetic sheet S when the grip body 100 is gripped at an angle that is easy for the user to draw. .. When the user moves the grip body 100 on the magnetic seed S and applies a magnetic force, characters, figures, and the like corresponding to the movement locus are drawn. At this time, the erasing unit 230 is separated from the drawing unit 220 at a constant angle or distance so that the magnetic force of the magnet 236 of the erasing unit 230 does not reach the magnetic sheet S.

FIG. 3B shows a state when characters and the like are erased by the erasing unit 230 of the writing unit 200 for bold characters. From the state shown in FIG. 3A, the user rotates the grip body 100 approximately 180 times around the axis to position the erasing unit 230 on the magnetic sheet S while maintaining the posture of the grip body 100. Can be done. Since the end face of the holder 234 of the erasing portion 230 is curved as described above, the end face of the holder 234 may be slightly inclined with respect to the magnetic sheet S. When the user moves the erasing unit 230 on the magnetic sheet S, the area corresponding to the movement locus is erased. At this time, the drawing unit 220 is separated from the erasing unit 230 at a constant angle or distance so that the magnetic force of the magnet 226 of the drawing unit 220 does not reach the magnetic sheet S.

As described above, according to the present embodiment, when drawing from drawing to erasing or drawing from erasing, the user draws or erases by rotating the grip body 100 half a turn without inverting the end portion of the magnetic writing instrument. It can be easily switched. Further, by making the bold writing unit 200 and the fine writing unit 300 detachable, they can be replaced with other writing units (for example, the bold writing unit 200 is replaced with the medium writing unit), or writing. It can be easily replaced with a new one when the part has reached the end of its life or when it breaks down.

In the above embodiment, the drawing unit 220 and the erasing unit 230 are fixedly attached to the grip body 100, but the main body 210 may be provided with an angle adjusting mechanism for the drawing unit 220 and the erasing unit 230. FIG. 4A is a front view of the writing section for bold type, and FIG. 4B is a schematic side view thereof. As shown in the figure, the connecting portion 222 of the drawing portion 220 and the connecting portion 232 of the erasing portion 230 may be housed in the recess 214 of the main body portion 210 and rotatably supported by the shaft 212. In this case, by appropriately selecting the relationship between the thickness of the two connecting portions 222 and 232 and the width of the recess 214, the drawing portion 220 and the erasing portion 230 are held in the recess 214 with a constant frictional force and are held. When an operating force larger than the frictional force is applied, the drawing unit 220 or the erasing unit 230 may rotate around the shaft 212 in θa and θb.

By making it possible to change the mounting angles of the drawing unit 220 and the erasing unit 230 in this way, even if the user changes the posture of the grip body 100 with respect to the magnetic sheet S, the drawing unit 220 and the erasing unit 230 correspond to the change. Can maintain a posture substantially perpendicular to the magnetic sheet S.

Next, a second embodiment of the present invention will be described. 5 (A) is a schematic schematic view of the drawing / erasing unit of the second embodiment when viewed from the front, and FIG. 5 (B) is a drawing / erasing unit 400 of FIG. 5 (A). Is a view seen from the magnetic sheet S side. In the second embodiment, as shown in FIG. 5A, a multi-type drawing / erasing unit 400 is provided at one end of the grip body 100. The drawing / erasing unit 400 has a main body 410 detachably attached to the grip main body 100, and a disk-shaped rotor portion 420 rotatably attached to the shaft 412 of the main body 410.

FIG. 5C shows a front view of the main body 410, and FIG. 5D shows a perspective view of the main body 410. One or more drawing portions and erasing portions are attached to the outer peripheral direction of the rotor portion 420 so as to be separated from each other at a predetermined angle. In the illustrated example, a drawing unit 430 for fine characters, an erasing unit 440, and a drawing unit 450 for bold characters are attached. The fine character drawing unit 430, the erase unit 440, and the bold character drawing unit 450 include a holder and a magnet arranged in the holder as in the previous embodiment. The angle θ1 between the fine print drawing unit 430 and the erase unit 440 and the angle θ2 between the erase unit 440 and the bold draw unit 450 are appropriately selected so that the magnets do not interfere with each other.

The user rotates the rotor unit 420 so that the fine character drawing unit 430, the erase unit 440, or the bold character drawing unit 450 is substantially perpendicular to the magnetic sheet S while holding the grip body 100 in an arbitrary posture. By applying a constant frictional force between the rotor portion 420 and the shaft 412, it is possible to stop the rotor portion 420 at an arbitrary angle and maintain its posture. Thereby, it is possible to correct the gripping habit of the user's grip body 100.

As shown in FIG. 5D, for example, the rotor portion 420 has a drawing portion 430 for fine characters, an erasing portion 440, and a drawing portion 450 for bold attachment to each ring 422, 424, 424, and these rings are integrated to form a shaft 412. Can be rotatably attached to. In this case, the angles θ1 and θ2 between the erasing unit / drawing unit can be changed by rotating each ring.

FIG. 5 (E) is a perspective view showing another configuration example of the main body portion. As shown in the figure, the main body portion 410A has a fine drawing portion 430, an erasing portion 440, and bold letters on the outer periphery of one ring 428. The drawing unit 450 may be attached. In this case, the angles θ1 and θ2 between the erasing unit and the drawing unit are fixed.

In the above embodiment, an example in which the drawing unit 430 for fine characters, the erasing unit 440, and the drawing unit 450 for bold characters are attached to the rotor unit 420 is shown as an example, and this is an example, and the number of drawing units is smaller or larger than this. Or an eraser may be attached. For example, in addition to the drawing unit for fine characters and the drawing unit for bold characters, an erasing unit for fine characters and an erasing unit for bold characters may be provided.

Next, a third embodiment of the present invention will be described with reference to FIG. The magnetic writing instrument 500 according to the third embodiment makes it possible to project the drawing portion or the erasing portion from the opening 114 at the tip by a knock type. In the grip body 100A, a plurality of cores 520, 530, 540, a bold drawing unit 522, an erasing unit 532, a fine character drawing unit 542, and a knock mechanism attached to the tips of the plurality of cores 520, 530, 540. 510 and are housed. The drawing unit and the erasing unit are configured in the same manner as in the above-described embodiment.

When the user operates a button (provided at the other end of the grip body 100A) that is not shown, the knock mechanism 510 selects the corresponding core, projects this core from the opening 114, and when the user operates the button again. , The knock mechanism 510 returns the protruding core to its original position. The example of FIG. 6 shows an example in which the core of the erasing unit 532 is selected and the erasing unit 532 protrudes from the opening 114.

When the erasing unit 532 protrudes from the opening 114, the magnets of the other bold drawing unit 522 and the fine character drawing unit 542 are in positions that do not interfere with the magnetic force of the erasing unit 532, that is, they do not affect the magnetic sheet. Absent. Similarly, when the bold drawing unit 522 or the fine character drawing unit 542 protrudes from the opening 114, the magnet in the grip body 100A does not affect the magnetic sheet.

In a preferred example, the outer diameter of the bold drawing unit 522 and the outer diameter of the shaft constituting the core 520 are equal, the outer diameter of the fine drawing unit 542 and the outer diameter of the shaft forming the core 540 are equal, and the erasing unit 532 The outer diameter and the outer diameter of the shafts constituting the core 530 are equal, and the outer diameters of the shafts constituting the cores 520, 530, and 540 are equal. Further, the inner diameter of the opening 114 is slightly larger than the outer diameter so that the bold drawing unit 522, the fine character drawing unit 542, and the erasing unit 532 can be taken in and out.

Next, the internal configuration of each drawing unit when the outer diameters of the bold drawing unit 522 and the fine character drawing unit 542 are the same will be described. FIG. 6B shows a schematic cross-sectional view of the bold drawing unit 522. The bold drawing unit 522 includes a cylindrical holder 550 having an outer diameter Dh made of a magnetic material and a magnet 552 arranged in the internal space of the holder 550. The outer diameter Dh is approximately equal to the outer diameter of the core 520. A circular opening 554 having a diameter of D1 is formed at the tip of the holder 550, and the surface of the magnet 552 is exposed through the opening 554. However, the opening 554 may be closed with a protective member made of a non-magnetic material such as plastic that can transmit magnetic lines of force. Assuming that the thickness of the holder 550 is t, the surface of the magnet 552 is located at a position recessed by a distance t from the tip surface of the holder 550. When drawing with the bold drawing unit 522, the user projects the bold drawing unit 522 from the opening 114 and slides the bold drawing unit 522 on the magnetic sheet. At this time, the magnetic field lines of the magnet 542 act on the magnetic sheet through the opening 554, and characters and the like corresponding to the movement locus of the bold drawing unit 522 are drawn.

On the other hand, as shown in FIG. 6C, the fine print drawing unit 542 is configured by using the holder 560 with an outer diameter Dh and the magnet 562 like the bold drawing unit 522, but the fine character drawing unit 542 A circular opening 564 with a diameter of D2 is formed at the tip of the holder 560 (D2 <D1). In the fine character drawing unit 542, since the range of the magnetic field lines acting on the outside is limited by reducing the diameter D2, it is possible to draw fine characters as compared with the bold character drawing unit 522.

FIG. 6D shows a schematic cross-sectional view of the erasing unit 532. The erasing unit 532 has a semi-cylindrical first holder 570 having an outer diameter Dh made of a magnetic material and a semi-cylindrical second holder having an outer diameter Dh made of a non-magnetic material such as plastic. Includes 572 and magnet 574. The open end of the first holder 570 and the open end of the second holder 572 are connected by an adhesive, an engaging mechanism, or the like, and a magnet 574 is arranged in the internal space thereof. When erasing with the erasing unit 532, the user projects the erasing unit 532 from the opening 114 and slides the erasing unit 532 on the magnetic sheet. At this time, the magnetic field lines of the magnet 574 act on the magnetic sheet via the second holder 572, and characters and the like are erased according to the movement locus of the erasing unit 532. Further, since the magnetic field lines of the magnet 574 are converged on the first holder 570 made of a magnetic material, it is possible to prevent the erasing range from being unnecessarily expanded. Further, by making the tip portion 576 of the second holder 572 semicircular, even if the grip body 100A is tilted with respect to the magnetic sheet, the second holder 572 easily slides on the magnetic sheet. be able to.

Although FIG. 6A shows an example in which one erasing unit is mounted, it is possible to mount a plurality of erasing units having different erasing ranges. To make the erasing range different, for example, the distance L from the tip portion 576 of the second holder 57 2 to the surface of the magnet 574 can be changed, the axial size of the magnet 574 can be changed, or the radial direction can be changed. You may change the size. The diameter of each core provided with each eraser is approximately equal to Dh.

As described above, according to the present embodiment, the user can easily switch between the drawing unit and the erasing unit simply by operating a button or the like. In the above example, an example in which three cores are accommodated is shown, but this is an example, and a smaller number (drawing part and erasing part) may be used, or a larger number (for bold) may be used. A drawing unit, a drawing unit for fine characters, an erasing unit for bold characters, an erasing unit for fine characters, etc.) may be accommodated.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In the first embodiment, an example in which the drawing unit and the erasing unit are detachable from the grip body is shown, but in the fourth embodiment, the drawing unit and the erasing unit are further configured to be detachable from the main body and drawn. It is possible to change the drawing function of the part and the erasing function of the erasing part.

As shown in the figure, the main body 600 is detachably attached to the grip main body 100 as in the case of the first embodiment. A connecting portion 620 is attached to the main body 600 via a shaft 610. The angle of the connecting portion 620 with respect to the main body portion 600 may be adjusted by rotating the shaft 610, for example. In the connecting portion 620, a columnar cavity portion 622 extending in the first direction and a columnar cavity portion 624 extending in the second direction are formed, and the first cavity portion 622 and the second cavity portion 622 are formed. The extending direction with the cavity 624 is approximately orthogonal. The drawing unit 630 is housed in the first cavity 622, and the erasing part 640 is housed in the second cavity 624.

The drawing portion 630 includes a cylindrical housing 632 that is detachably housed in the first cavity portion 622, a holder 634 made of a magnetic material held in the internal space of the housing 632, and a holder 634. It has a magnet 636 held in the housing. The housing 632 is made of a non-magnetic material such as plastic. The tip of the holder 634 is formed with a circular opening for exposing the surface of the magnet 636, as described in the third embodiment (see FIGS. 6B and 6C).

In this embodiment, it is possible to remove the drawing portion 630 from the first cavity portion 622 and insert another drawing portion into the first cavity portion 622. The outer diameters of the respective housings 632 are equal in the plurality of interchangeable drawing parts. Further, the outer diameter of the housing 632 is substantially equal to the inner diameter of the first cavity portion 622. For example, the first cavity portion 622 and the housing 632 may be fixed by fitting, and the first cavity portion 622 may also include a latch mechanism for fixing the housing 632. It is also possible to form a threaded portion on the inner circumference of the first cavity portion 622 and a threaded portion on the outer circumference of the housing 632 to connect the two. In one example, the drawing unit 630 is replaced when the line thickness when drawing with the drawing unit 630 is changed. For example, the bold drawing section is replaced with the fine drawing section, and vice versa. As shown in FIG. 6B of the third embodiment, the bold drawing portion is formed with a relatively large opening having a diameter D1 at the tip end portion of the holder. On the other hand, as shown in FIG. 6C, the fine print drawing portion is formed with an opening having a relatively small diameter D2 at the tip portion of the holder. Further, as another example of replacement, the drawing unit 630 can be replaced with a new drawing unit due to aging or failure.

The erasing unit 640 has a semi-cylindrical first holder 642 made of a magnetic material and a half made of a non-magnetic material, as in the fourth embodiment (see FIG. 6D). Includes a second cylindrical holder 644 and a magnet 646. The open end of the first holder 642 and the open end of the second holder 644 are coupled, and the magnet 646 is arranged in the internal space thereof. By making the tip of the second holder 642 semicircular, even if the grip body 100 is tilted with respect to the magnetic sheet, the second holder 642 can easily slide on the magnetic sheet. .. At that time, the magnetic field lines of the magnet 646 act on the magnetic sheet via the second holder 642, and the drawn figures and the like are erased.

In this embodiment, it is possible to remove the eraser 640 from the second cavity 624 and insert another eraser into the second cavity 624. The outer diameters of the first and second holders 642 and 644 are equal in the plurality of replaceable erasers, respectively. Further, the outer diameters of the first and second holders 642 and 644 are substantially equal to the inner diameter of the second cavity portion 624. For example, the second cavity portion 624 and the first and second holders 642 and 644 may be fixed by fitting, and the second cavity portion 624 may also have the first and second holders. A latch mechanism for fixing 642 and 644 may be provided, or a screw portion is formed on the inner circumference of the second cavity portion 624 and a screw portion is formed on the outer circumference of the first and second holders 642 and 644. It is also possible to form and combine the two.

In one example, when the erasing range of the erasing unit 640 is changed, the erasing unit 640 is replaced with another erasing unit 640. For example, in the erasing unit 640A shown in FIG. 7 (B), the distance from the tip of the second holder 644 to the surface of the magnet 646 is L1, and the erasing unit 640B shown in FIG. 7 (C) is the second holder. The distance from the tip of 644 to the surface of the magnet 646 is L2 (L1 <L2).
By changing the distance from L1 to L2, the range in which the magnetic field lines of the magnet 646 extend to the magnetic sheet becomes smaller, and the erasing range becomes narrower. Alternatively, a plurality of erasing portions having different sizes of the magnets 646 may be prepared and an arbitrary erasing portion may be selected. Further, the erasing unit 640C shown in FIG. 7D adjusts the strength or spread of the magnetic field lines of the magnet 646 by arranging the magnetic body 648 between the magnet 646 and the tip of the second holder 644. It changes the erasure range. By preparing a plurality of erasing portions having different erasing ranges, the user can select an arbitrary erasing portion and attach it to the second cavity portion 624.

According to this embodiment, the user can freely replace the functions of the drawing unit and the erasing unit attached to the end of the grip body with the functions of the other drawing unit and the erasing unit, which enhances the convenience of the magnetic writing instrument. It can be further improved.

Next, a fifth embodiment of the present invention will be described with reference to FIG. A fifth embodiment makes it possible to attach the erasing member to the magnetic writing instrument in a detachable manner. As shown in the figure, the magnetic writing instrument 10A has a drawing unit 700 at its end. The drawing unit 700 is configured in the same manner as the drawing unit (see FIGS. 6B and 6C) described in, for example, the fourth embodiment. Further, an erasing member 710 is detachably attached in the vicinity of the drawing unit 700 of the magnetic writing unit 10A.

The erasing member 710 has a ring body 720 and an erasing unit 730 connected to the ring body 720. The ring body 720 has an opening 722 into which the grip body 100 of the magnetic writing unit 10A can be inserted, and the grip body 100 is detachably held in the opening 722. The material of the ring body 720 is arbitrary, but it can be made of an elastic material such as plastic or rubber. In one example, the inner diameter of the opening 722 of the ring body 720 is somewhat smaller than the outer diameter of the grip body 100, and the ring body 720 elastically holds the grip body 100.

The erasing unit 730 is connected to the ring body 720 so as to be separated from the drawing unit 700 of the pen tip by a certain distance or angle. The erasing unit 730 holds the magnet in the holder as described in the previous embodiment (see FIG. 6D), and the tip portion 732 of the holder has a circular shape. In this embodiment, the user can attach the erasing member 710 to the tip of the magnetic writing instrument 10A so that the magnetic writing instrument 10A has an erasing function. Further, as in the fifth embodiment, by preparing a plurality of erasing members having different erasing functions or erasing ranges, the user can select the optimum erasing member 710 and attach it to the magnetic writing instrument 10A. it can.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various aspects are within the scope of the gist of the present invention described in the claims. It can be transformed and changed.

10,500: Magnetic writing instrument 100, 100A: Grip body 110, 112: Opening 200: Writing part for bold 210: Body part 212: Axis 220: Drawing part 222: Connecting part 224: Holder 226: Magnet 230: Erasing part 232: Connecting part 234: Holder 236: Magnet 238: Magnetic force adjustment ring 300: Writing part for fine print 310: Main body part 320: Drawing part 330: Erasing part

Claims (7)

A magnetic writing instrument that has the function of drawing characters, etc. on the magnetic sheet by applying a magnetic field on the magnetic sheet, and erasing the drawn characters, etc.
Grip body and
It has a drawing portion and an erasing portion provided at at least one end of the grip body.
A magnetic writing instrument in which the drawing unit and the erasing unit each include a magnet and are separated from the drawing unit and the erasing unit so as not to interfere with each other. The magnetic writing instrument according to claim 1, wherein the drawing unit and the erasing unit are rotatable with respect to the grip body. The magnetic writing instrument according to claim 1 or 2, wherein the drawing unit and the erasing unit are detachably attached to the grip body. The grip body further includes another set of drawing and erasing parts at the other end, the drawing and erasing parts provided at one end being for bold or fine print and at the other end. The magnetic writing instrument according to any one of claims 1 to 3, wherein the drawing unit and the erasing unit provided are for fine characters or bold characters. The magnetic writing instrument according to claim 1, wherein the angle between the drawing unit and the erasing unit is variable. The magnetic writing instrument according to claim 1, wherein the drawing unit or the erasing unit projects from an opening of a grip body by a knock mechanism. The magnetic writing instrument according to claim 1, wherein the drawing portion or the erasing portion is detachable from a main body portion attached to a grip main body.

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