Sharp pencil

Abstract

To prevent lead jamming in a mechanical pencil.SOLUTION: A mechanical pencil 10 includes a first storage chamber C1 capable of containing writing leads 80, a second storage chamber C2 located behind the first storage chamber C1 and capable of containing writing leads 80, and a connecting member 40 which connects the first storage chamber C1 and the second storage chamber C2 and has a passage 42 through which the writing leads 80 can pass from the second storage chamber C2 toward the first storage chamber C1.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a sharp pencil.

Background Art

[0002] Conventionally, a sharp pencil including a shaft cylinder, a core housing chamber for housing a writing core, and a chuck for feeding the writing core forward from the core housing chamber has been well known. In such a sharp pencil, when a user presses the rear end of the sharp pencil, the writing core is fed forward from the core housing chamber by the chuck, and the tip of the writing core protrudes from the tip of the sharp pencil. In this state, when the user rubs the tip of the writing core against a writing surface such as paper, a handwriting is formed on the writing surface by the writing core. In the core housing chamber, a writing core different from the writing core in use, that is, a spare core, can be housed. When the writing core in use is consumed, one of the spare cores housed in the core housing chamber is fed forward by the chuck and used for writing. Patent Document 1 discloses an example of a conventional sharp pencil.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional sharp pencil, in order for a user to save the trouble of replenishing a spare writing core (spare core), the user may put a large number of spare cores in the core housing chamber. In this case, when the writing core in use is consumed, the large number of spare cores housed in the core housing chamber may interfere with each other in moving forward, and the tip of the spare core may not protrude from the tip of the sharp pencil, so-called core clogging may occur.

[0005] In addition, when the protruding amount of the tip of the refill from the tip of the mechanical pencil is too large, the user may press the rear end of the mechanical pencil or the like to press the tip of the refill against the writing surface or the like with the chuck open, causing the refill to retract. Also, when replenishing the mechanical pencil with a refill, there may be a case where the refill is inserted while retracting the refill from the tip side of the mechanical pencil with the chuck open. In such a case, the spare refill may be sandwiched between the rear end of the retracted refill and any member in the refill storage chamber, and the spare refill may break. The broken spare refill moves to the front part of the refill storage chamber during writing. In this case, when the refill in use is consumed, the broken spare refill may prevent other spare refills from moving forward, and in this case as well, so-called refill jamming may occur.

[0006] The present invention has been made in consideration of such points, and an object thereof is to suppress the occurrence of refill jamming in a mechanical pencil.

Means for Solving the Problems

[0007] The mechanical pencil according to the present invention has a first storage chamber capable of storing a refill, a second storage chamber located behind the first storage chamber and capable of storing a refill, and a connecting member that connects the first storage chamber and the second storage chamber and has a passage through which the refill can pass from the second storage chamber toward the first storage chamber.

[0008] In the mechanical pencil according to the present invention, the passage may be located radially offset from the central axis of the mechanical pencil.

[0009] In the mechanical pencil according to the present invention, the passage may include a hole provided in the connecting member.

[0010] In the mechanical pencil according to the present invention, The connecting member has a main body portion and a rear protruding portion that protrudes rearward from the main body portion. The passage may include a groove provided on an outer surface of the rear protruding portion.

[0011] In the mechanical pencil according to the present invention, The connecting member may have a guide portion that guides the refill to the passage.

[0012] In the mechanical pencil according to the present invention, has a clip, The passage may be located on the side opposite to the clip with respect to the central axis of the mechanical pencil.

[0013] The mechanical pencil according to the present invention has a storage chamber capable of storing a refill, and a retreat space located behind the storage chamber and allowing the refill in the storage chamber to retreat. The dimension in the direction orthogonal to the central axis in the retreat space is smaller than the dimension in the direction orthogonal to the central axis in the storage chamber.

[0014] In the mechanical pencil according to the present invention, The dimension in the direction orthogonal to the central axis in the retreat space may be smaller than 1 / 2 of the dimension in the direction orthogonal to the central axis in the storage chamber.

[0015] In the mechanical pencil according to the present invention, The central axis of the retreat space may coincide with the central axis of the storage chamber.

[0016] In the mechanical pencil according to the present invention, a connecting member connected to the rear end of the storage chamber, and a pipe member connected to the connecting member from the rear. The space inside the pipe member may form at least a part of the retreat space.

[0017] In the mechanical pencil according to the present invention, The rear end of the retraction space may be closed.

Advantages of the Invention

[0018] According to the present invention, it is possible to suppress the occurrence of lead clogging in the mechanical pencil.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to this specification, for the convenience of illustration and easy understanding, the scale, the aspect ratio in the vertical and horizontal directions, etc. are appropriately changed and exaggerated from those of the actual object.

[0021] In addition, regarding the terms used in this specification for specifying the shape, geometric conditions, and their degrees, such as terms like "parallel", "orthogonal", "identical", etc., and values of lengths and angles, etc., they are not bound by strict meanings and are to be interpreted to include ranges that can be expected to have similar functions.

[0022] In this specification, the direction in which the central axis A of the mechanical pencil extends (the longitudinal direction, the vertical direction in the longitudinal sectional view) is defined as the axial direction da, the direction orthogonal to the axial direction da is defined as the radial direction dr, and the direction along the circumference around the central axis A is defined as the circumferential direction dc. Also, along the axial direction da, the side closer to the writing surface such as paper when writing is defined as the front, and the side separated from the writing surface is defined as the rear.

[0023] FIG. 1 is a longitudinal sectional view showing a mechanical pencil 10 according to the present invention. The mechanical pencil 10 includes a shaft cylinder 20 and a lead operating unit 30. The shaft cylinder 20 includes a shaft cylinder main body 22, a tip member 24 located in front of the shaft cylinder main body 22, a sleeve 25 attached to the front end of the tip member 24, and a connecting member 26 that connects the shaft cylinder main body 22 and the tip member 24 to each other. A clip 28 is provided on the outer surface of the rear portion of the shaft cylinder main body 22. The shaft cylinder main body 22 has a cylindrical shape extending in the axial direction da along the central axis A of the mechanical pencil 10. Therefore, the central axis of the shaft cylinder main body 22 coincides with the central axis A of the mechanical pencil 10. At least a part of the lead operating unit 30 is disposed inside the shaft cylinder main body 22. The tip member 24 is a member that forms the tip portion of the mechanical pencil 10. The tip member 24 has a substantially conical shape, and its outer diameter decreases toward the front. The shaft cylinder main body 22 and the connecting member 26 are connected to each other by screwing a female screw portion formed on the inner surface of the front end of the shaft cylinder main body 22 onto a male screw portion formed on the outer surface of the rear end of the connecting member 26. Also, the tip member 24 and the connecting member 26 are connected to each other by screwing a female screw portion formed on the inner surface of the rear end of the tip member 24 onto a male screw portion formed on the outer surface of the front end of the connecting member 26. Thereby, the shaft cylinder main body 22 and the tip member 24 are connected to each other via the connecting member 26. The sleeve 25 is fixed to the tip member 24. The writing lead 80 fed forward by the lead operating unit 30 passes through the sleeve 25 and protrudes from the front end of the sleeve 25.

[0024] The refill operation unit 30 has a mechanism for feeding out the refill 80 forward by the operation of the user. The refill operation unit 30 of the present embodiment includes a first refill pipe 32, a second refill pipe 34, a cap 38, a connection member 40, a pipe member 50, a chuck 61, a resilient member 62, a receiving member 63, a fastener 64, and a refill holder 65.

[0025] Both the first refill pipe 32 and the second refill pipe 34 are members for accommodating the refill 80. The first refill pipe 32 forms a first accommodation chamber (accommodation chamber) C1 capable of accommodating the refill 80. The second refill pipe 34 is located behind the first refill pipe 32. The second refill pipe 34 forms a second accommodation chamber C2 capable of accommodating the refill 80. Therefore, the second accommodation chamber C2 is located behind the first accommodation chamber C1. The connection member 40 connects the first refill pipe 32 and the second refill pipe 34 to each other. Therefore, the connection member 40 is a connection member that connects the first accommodation chamber C1 and the second accommodation chamber C2 to each other. The connection member 40 has a passage 42 through which the refill 80 can pass from the second accommodation chamber C2 to the first accommodation chamber C1. Details of the connection member 40 will be described later. In the present embodiment, the first refill pipe 32, the second refill pipe 34, and the connection member 40 also have a function of transmitting the pressing force from the cap 38 to the chuck 61 when the user presses the cap 38 forward. The first refill pipe 32 and the second refill pipe 34 are formed of, for example, resin.

[0026] The pipe member 50 is a member that forms a retreat space S in which the refill 80 in the first accommodation chamber (accommodation chamber) C1 can retreat. The pipe member 50 is attached to the rear portion of the connection member 40. Therefore, the pipe member 50 is located behind the first refill pipe 32. Also, the pipe member 50 is located behind the first accommodation chamber (accommodation chamber) C1. In the example shown in FIG. 1, the pipe member 50 is located inside the second refill pipe 34. That is, the pipe member 50 is located in the second accommodation chamber C2. Details of the pipe member 50 will be described later.

[0027] The mechanical pencil 10 of the present embodiment is configured to suppress the occurrence of lead jams by limiting the number of lead cores 80 accommodated in the first storage chamber C1. On the other hand, by further providing a second storage chamber C2 capable of accommodating the lead cores 80, a large number of lead cores 80 can be accommodated in the mechanical pencil 10. Further, the mechanical pencil 10 of the present embodiment has a connecting member 40 that connects the first storage chamber C1 and the second storage chamber C2 and has a passage through which the lead core 80 can pass from the second storage chamber C2 toward the first storage chamber C1, so that when the number of lead cores 80 accommodated in the first storage chamber C1 decreases, the lead cores 80 accommodated in the second storage chamber C2 can move to the first storage chamber C1.

[0028] Further, when the mechanical pencil 10 of the present embodiment retracts the lead core 80 that protrudes greatly from the tip of the mechanical pencil 10, or when inserting the lead core 80 while retracting it from the tip side of the mechanical pencil 10, the retreat space S is configured to allow other lead cores 81 pressed rearward by the retracted lead core 80 to retreat rearward.

[0029] An eraser 36 is detachably attached to the rear end portion of the second lead pipe 34. Note that the eraser 36 can be omitted. The cap 38 is a member attached to the rear end portion of the second lead pipe 34 and covering the rear end of the second lead pipe 34. When the mechanical pencil 10 has the eraser 36 attached to the rear end portion of the second lead pipe 34, the cap 38 also functions as a cover covering the eraser 36. In the present embodiment, the cap 38 is also a knock body that is pressed forward by the user when feeding out the lead core 80. In the example shown in FIG. 1, the eraser 36 can be used by removing the cap 38 from the second lead pipe 34. Further, by removing the cap 38 and the eraser 36 from the second lead pipe 34, the user can replenish the lead core 80 into the second lead pipe 34.

[0030] The chuck 61 is a member that holds the refill 80. The chuck 61 can move in the front - rear direction integrally with the first core pipe 32. In the example shown in FIG. 1, the rear end portion of the chuck 61 is inserted into the front end portion of the first core pipe 32, whereby the chuck 61 is fixed to the first core pipe 32.

[0031] A resilient member 62 is disposed in front of the first core pipe 32. The resilient member 62 is, for example, a coil spring. A receiving member 63 is disposed in front of the resilient member 62, and the resilient member 62 is disposed in a compressed state between the front end portion of the first core pipe 32 and the receiving member 63. The receiving member 63 is a member that receives the elastic force of the resilient member 62, is pressed forward by the elastic force of the resilient member 62, and abuts against a stepped portion formed on the inner surface of the tip member 24. The clamp 64 is an annular component located radially outside the front portion of the chuck 61. When the rear end portion of the clamp 64 abuts against the receiving member 63, the backward movement of the clamp 64 is restricted. The core holder 65 is disposed in front of the chuck 61 and is a member that abuts against the outer surface of the refill 80 and holds the refill 80. The core holder 65 is formed of an elastic member such as rubber and suppresses the axial movement of the refill 80 in the axial direction da when the chuck 61 does not grip the refill 80.

[0032] When the refill outlet unit 30 feeds out the refill 80, the user presses the cap 38 forward. As a result, the second refill pipe 34, the connecting member 40, the first refill pipe 32, and the chuck 61 move forward against the elastic force of the elastic member 62. The outer surface of the front portion of the chuck 61 abuts against the fastener 64 from the inside when the cap 38 is not being pressed forward. Therefore, the front portion of the chuck 61 is prevented from opening radially outward. As a result, the front portion of the chuck 61 grips the refill 80. When the chuck 61 moves forward together with the fastener 64, the refill 80 gripped by the chuck 61 moves forward. When the chuck 61 moves further forward, the fastener 64 abuts against the inner step of the tip member 24 and the front portion of the chuck 61 moves forward with respect to the fastener 64. As a result, the front portion of the chuck 61 opens outward, and the refill 80 held by the front portion of the chuck 61 is released. At this time, the refill 80 is held by the refill holder 65.

[0033] When the pressing of the cap 38 by the user is released, the elastic force of the elastic member 62 causes the cap 38, the second refill pipe 34, the connecting member 40, the first refill pipe 32, and the chuck 61 to move backward. As a result, the front portion of the chuck 61 moves inside the fastener 64, abuts against the fastener 64, and grips the refill 80. At this time, since the refill 80 is held by the refill holder 65, the backward movement of the refill 80 is suppressed. By repeating this, the refill 80 is fed forward, and the front end of the refill 80 protrudes forward from the front end of the sleeve 25 through the sleeve 25.

[0034] With reference to FIGS. 2 to 5, the details of the connecting member 40 and the pipe member 50 will be described. FIG. 2 is an enlarged view showing the connecting member 40, FIG. 3 is a cross-sectional view of the sharp pencil 10 corresponding to line III-III of FIG. 2, FIG. 4 is a perspective view showing the connecting member 40, and FIG. 5 is a cross-sectional view showing the connecting member 40.

[0035] The connecting member 40 is a member that connects the first accommodation chamber C1 and the second accommodation chamber C2. The connecting member 40 has a passage 42 through which the refill 80 can pass from the second accommodation chamber C2 toward the first accommodation chamber C1. The connecting member 40 is formed of, for example, resin. In particular, in order for the refill 80 to pass smoothly through the passage 42, the connecting member 40 is preferably formed of a material with high surface slipperiness. As a material with high surface slipperiness, for example, polyacetal resin or the like can be used.

[0036] The connecting member 40 has a main body portion 44 and a rear protruding portion 46 that protrudes rearward from the main body portion 44. The main body portion 44 and the rear protruding portion 46 each have a hollow substantially cylindrical shape. The outer diameter of the rear protruding portion 46 is smaller than the outer diameter of the main body portion 44. The main body portion 44 and the rear protruding portion 46 each have a through hole extending in the axial direction da, and the through hole of the main body portion 44 and the through hole of the rear protruding portion 46 communicate with each other.

[0037] The main body portion 44 has a first contact portion 44a that contacts the first core pipe 32 and receives the first core pipe 32, and a second contact portion 44b that contacts the second core pipe 34 and receives the second core pipe 34. The first contact portion 44a is the front-facing surface at a stepped portion provided on the inner surface of the through hole of the main body portion 44. The rear end of the first core pipe 32 is inserted into the through hole of the main body portion 44 from the front and contacts the first contact portion 44a. Thereby, the first core pipe 32 and the connecting member 40 are fixed to each other. The second contact portion 44b is the rear-facing surface on the outer surface of the main body portion 44. In the illustrated example, the second contact portion 44b is located at the rear end of the main body portion 44. Also, the second contact portion 44b is located outside the rear protruding portion 46 in the radial direction dr. The front end of the second core pipe 34 is attached to the outside of the rear protruding portion 46 from the rear and contacts the second contact portion 44b. Thereby, the second core pipe 34 and the connecting member 40 are fixed to each other.

[0038] At the rear part of the inner surface of the through hole of the main body portion 44, an inner inclined surface 44c is provided. The inner inclined surface 44c extends in a direction inclined with respect to both the axial direction da and the radial direction dr. The inner inclined surface 44c extends so as to approach the central axis A as it goes rearward. The rear end of the inner inclined surface 44c is connected to the internal space of the rear projecting portion 46. The inner inclined surface 44c is also a guide surface for guiding the writing core 80 when the writing core 80 in the first accommodation chamber C1 retreats toward the retreat space S.

[0039] The rear projecting portion 46 has a third contact portion 46a for receiving the pipe member 50. The third contact portion 46a is the surface facing rearward in a stepped portion provided on the inner surface of the through hole of the rear projecting portion 46. The front end of the pipe member 50 is inserted into the through hole of the rear projecting portion 46 from the rear and abuts against the third contact portion 46a. Thereby, the pipe member 50 and the connection member 40 are fixed to each other.

[0040] As long as the writing core 80 can pass from the second accommodation chamber C2 to the first accommodation chamber C1, the specific shape and dimensions of the passage 42 are not particularly limited. In the present embodiment, the passage 42 includes a hole 44d provided in the main body portion 44 and a groove 46b provided in the rear projecting portion 46. The hole 44d is a through hole connecting the inner surface of the main body portion 44 and the groove 46b. In the particularly illustrated example, the hole 44d connects the inner inclined surface 44c of the main body portion 44 and the groove 46b. The groove 46b is provided on the outer surface of the rear projecting portion 46. The groove 46b extends parallel to the axial direction da. The passage 42 is configured as a passage extending parallel to the axial direction da as a whole. Therefore, the writing core 80 can move in the passage 42 in a direction parallel to the axial direction da. The minimum dimension of the passage 42 in the direction orthogonal to the axial direction da is larger than the diameter of the writing core 80 to be accommodated in the mechanical pencil 10. For example, when the diameter of the writing core 80 to be accommodated in the mechanical pencil 10 is 0.57 mm, the minimum dimension of the passage 42 in the direction orthogonal to the axial direction da is designed to be larger than 0.57 mm. The dimensions of the passage 42 may be designed such that only one writing core 80 can pass through, or may be designed such that a plurality of writing cores 80 can pass through simultaneously.

[0041] In this embodiment, the passage 42 is located offset in the radial direction dr from the central axis A of the mechanical pencil 10. In this case, when the passage 42 is located vertically downward with respect to the central axis A (see FIG. 6), the refill 80 housed in the second storage chamber C2 is likely to be guided toward the passage 42 by the action of gravity. Therefore, the refill 80 can be smoothly moved from the second storage chamber C2 toward the first storage chamber C1.

[0042] Also, in this embodiment, the passage 42 is located on the side opposite to the clip 28 with respect to the central axis A of the mechanical pencil 10. When writing with the mechanical pencil 10, the user often holds the mechanical pencil 10 with the clip 28 facing upward. In this case, the passage 42 located on the side opposite to the clip 28 with respect to the central axis A will be located vertically downward with respect to the central axis A (see FIG. 6). Therefore, even if the user does not consciously position the passage 42 downward with respect to the central axis A, just by holding the mechanical pencil 10 with the clip 28 facing upward, the passage 42 can be positioned downward with respect to the central axis A.

[0043] The connecting member 40 may have guide portions 44e, 46c, 46d that guide the refill 80 to the passage 42. The rear protruding portion 46 has a first inclined surface 46c and a second inclined surface 46d. The first inclined surface 46c extends in a direction inclined with respect to both the bottom surface 46b1 of the groove 46b and the rear end surface 46e of the rear protruding portion 46. The first inclined surface 46c connects the bottom surface 46b1 and the rear end surface 46e. In the illustrated example, the first inclined surface 46c intersects the through-hole of the rear protruding portion 46, and a straight line extending the straight line connecting the rear end surface 46e and the first inclined surface 46c intersects the central axis A of the mechanical pencil 10. The first inclined surface 46c extends forward as it moves away from the central axis A. When the front end of the refill 80 housed in the second housing chamber C2 abuts against the first inclined surface 46c, the front end of the refill 80 is guided by the first inclined surface 46c and can move into the passage 42. That is, the first inclined surface 46c functions as a guide portion that guides the refill 80 toward the passage 42.

[0044] The second inclined surface 46d extends in a direction inclined with respect to the side surface 46b2 from the rear end of the side surface 46b2 of the groove 46b. The groove 46b has a pair of opposing side surfaces 46b2. The connecting member 40 has two second inclined surfaces 46d corresponding to each of the pair of side surfaces 46b2. The second inclined surface 46d connected to one of the pair of side surfaces 46b2 extends away from the other side surface 46b2 as it goes rearward. Also, the second inclined surface 46d connected to the other side surface 46b2 extends away from the one side surface 46b2 as it goes rearward. When the front end of the refill 80 housed in the second housing chamber C2 abuts against the second inclined surface 46d, the front end of the refill 80 is guided by the second inclined surface 46d and can move into the passage 42. That is, the second inclined surface 46d functions as a guide portion that guides the refill 80 toward the passage 42. Note that the first inclined surface 46c and the second inclined surface 46d may be flat surfaces or curved surfaces.

[0045] A groove 44e extending in the radial direction dr is formed on the rear end surface of the main body portion 44. The groove 44e communicates with the passage 42. In particular, the groove 44e communicates with the hole 44d and also communicates with the groove 46b. When the connecting member 40 has such a groove 44e, the front end of the refill 80 accommodated in the second accommodation chamber C2 fits into the groove 44e. The refill 80 with its front end positioned within the groove 44e can move along the groove 44e toward the passage 42. That is, the groove 44e functions as a guide portion that guides the refill 80 with its front end positioned within the groove 44e toward the passage 42.

[0046] Next, the retreat space S will be described. When retracting the refill 80 that protrudes significantly from the tip of the mechanical pencil 10, or when inserting the refill 80 while retracting it from the tip side of the mechanical pencil 10, there is a risk that another refill 81 will be pinched between the rear end of the retracted refill 80 and the rear end portion of the first accommodation chamber (accommodation chamber) C1, and the other refill 81 may break. The broken refill 81 moves to the front portion of the first accommodation chamber C1 during writing. In this case, when the used refill 80 is consumed, the broken refill 81 may prevent the other refill 80 from moving forward, causing so-called lead clogging. To suppress the occurrence of such lead clogging, in the present embodiment, the mechanical pencil 10 is provided with a retreat space S in which the other refill 81 pressed backward by the retracted refill 80 can retreat. Note that FIG. 1 shows an example in which another refill 81 is positioned behind the refill 80 held by the chuck 61 and used for writing.

[0047] In this embodiment, the mechanical pencil 10 has a pipe member 50 connected to the connecting member 40 from the rear. The space inside the pipe member 50 forms at least a part of the retraction space S. The retraction space S may be configured to include only the space inside the pipe member 50. Further, the retraction space S may be configured to include the space inside the pipe member 50 and the space inside the connecting member 40. The retraction space S is located behind the first accommodation chamber C1 and allows the refill 80 in the first accommodation chamber (accommodation chamber) C1 to retract. The pipe member 50 is inserted into the through-hole of the rear protruding portion 46 from the rear. The front end of the pipe member 50 abuts against the third abutting portion 46a of the rear protruding portion 46. The pipe member 50 is a tubular member extending in a direction parallel to the central axis A of the mechanical pencil 10. The pipe member 50 is formed of, for example, resin or metal.

[0048] The retraction space S communicates with the first accommodation chamber C1. In this embodiment, the central axis of the retraction space S coincides with the central axis of the first accommodation chamber C1. Note that the central axis of the first accommodation chamber C1 coincides with the central axis A of the mechanical pencil 10. Also, the central axis of the retraction space S coincides with the central axis A of the mechanical pencil 10. Since the central axis of the retraction space S coincides with the central axis of the first accommodation chamber C1, another refill 81 that is pressed against the rear end of the retracted refill 80 along the central axis of the first accommodation chamber C1 and moves rearward can be appropriately retracted. As described above, the main body portion 44 of the connecting member 40 has an inner inclined surface 44c. Therefore, the rear end of another refill 81 that is pressed against the rear end of the retracted refill 80 and moves rearward can be guided to the inner inclined surface 44c and directed toward the retraction space S.

[0049] The dimension in the direction orthogonal to the central axis in the retraction space S is smaller than the dimension in the direction orthogonal to the central axis in the first accommodation chamber C1. Here, the dimension in the direction orthogonal to the central axis refers to the minimum dimension among the dimensions measured so as to pass through the central axis in the cross-section orthogonal to the central axis of the member. When the retraction space S and the first accommodation chamber C1 are each a cylindrical space, the dimensions in the direction orthogonal to the central axis in the retraction space S and the first accommodation chamber C1 are the diameters of the retraction space S and the first accommodation chamber C1, respectively. In the present embodiment, the inner diameter of the pipe member 50 is smaller than the inner diameter of the first accommodation chamber C1. Thereby, the dimension in the direction orthogonal to the central axis in the retraction space S is smaller than the dimension in the direction orthogonal to the central axis in the first accommodation chamber C1. In this case, the volume occupied by the retraction space S can be reduced. Therefore, it becomes possible to effectively utilize the space inside the mechanical pencil 10. Further, when the mechanical pencil 10 has the passage 42, it is also possible to arrange the retraction space S and the passage 42 side by side in the direction orthogonal to the central axis. The dimension in the direction orthogonal to the central axis in the retraction space S may be smaller than 1 / 2 of the dimension in the direction orthogonal to the central axis in the first accommodation chamber C1. In this case, the volume occupied by the retraction space S can be further reduced. Therefore, it becomes possible to more effectively utilize the space inside the mechanical pencil 10.

[0050] The dimension in the direction orthogonal to the central axis in the retraction space S is larger than the diameter of the refill 80 to be accommodated in the mechanical pencil 10. For example, when the diameter of the refill 80 to be accommodated in the mechanical pencil 10 is 0.57 mm, the dimension in the direction orthogonal to the central axis in the retraction space S is designed to be larger than 0.57 mm. Further, the dimension in the direction orthogonal to the central axis in the retraction space S may be smaller than twice the diameter of the refill 80 to be accommodated in the mechanical pencil 10. For example, when the diameter of the refill 80 to be accommodated in the mechanical pencil 10 is 0.57 mm, the dimension in the direction orthogonal to the central axis in the retraction space S may be designed to be smaller than 1.14 mm. In this case, only one refill 80 can enter the retraction space S.

[0051] The rear end of the retraction space S may be open or closed. When the rear end of the retraction space S is open, the refill 80 accommodated in the first accommodation chamber C1 can be taken out through the retraction space S. Further, when the rear end of the retraction space S is closed, when the user replenishes the refill 80 in the second accommodation chamber C2, it is possible to prevent the refill 80 to be replenished from accidentally entering the retraction space S.

[0052] Next, the operation of the Sharp pencil 10 of the present embodiment will be described. FIG. 6 is a diagram showing a state of writing using the Sharp pencil 10.

[0053] The user removes the cap 38 and the eraser 36 from the second core pipe 34 and replenishes the refill 80 into the second core pipe 34. Thereafter, the eraser 36 and the cap 38 are attached to the second core pipe 34.

[0054] As shown in FIG. 6, when writing on a writing surface 90 such as paper, the user usually holds the Sharp pencil 10 such that the central axis A is inclined with respect to both the writing surface 90 and the vertical direction. In FIG. 6, the writing surface 90 extends in the horizontal direction, and it is assumed that gravity acts downward in FIG. 6. That is, the vertical direction in FIG. 6 is the vertical direction. When the user holds the Sharp pencil 10 such that the passage 42 is located below the central axis A in the vertical direction, the refill 80 accommodated in the second accommodation chamber C2 is guided toward the passage 42 by the action of gravity. In particular, in the example shown in FIG. 6, the passage 42 is located on the side opposite to the clip 28 with respect to the central axis A of the Sharp pencil 10. When writing with the Sharp pencil 10, the user often holds the Sharp pencil 10 such that the clip 28 faces upward. In this case, the passage 42 located on the side opposite to the clip 28 with respect to the central axis A is positioned below the central axis A.

[0055] The refill 80 guided to the passage 42 moves through the passage 42 toward the inside of the first storage chamber C1 under the action of gravity. The dimensions of the first storage chamber C1 are designed such that the number of refills 80 accommodated in the first storage chamber C1 is limited. Thereby, when the refill 80 in use is consumed, it is possible to suppress a situation where a large number of refills 80 accommodated in the first storage chamber C1 impede each other from moving forward. Therefore, it is possible to effectively suppress the occurrence of clogging of the refills in the first storage chamber C1.

[0056] Also, in the Sharp pencil 10 of the present embodiment, a large number of refills 80 can be accommodated in the second storage chamber C2. Thereby, the number of times of replenishing the refills 80 into the Sharp pencil 10 can be reduced.

[0057] When retracting the refill 80 that protrudes greatly from the tip of the Sharp pencil 10, or when inserting the refill 80 while retracting it from the tip side of the Sharp pencil 10, if another refill 81 is pressed backward by the retracted refill 80, the pressed other refill 81 can retreat into the retreat space S. Thereby, it is possible to suppress another refill 81 from being sandwiched between the rear end of the retracted refill 80 and any member in the storage chamber, for example, the rear end portion of the first storage chamber C1, and prevent the other refill 81 from breaking. Therefore, it is possible to effectively suppress the broken refill 81 from moving to the front portion of the first storage chamber C1 during writing and causing clogging of the refills due to this refill 81.

[0058] The Sharp pencil 10 of the present embodiment includes a first storage chamber C1 capable of accommodating the refill 80, a second storage chamber C2 located behind the first storage chamber C1 and capable of accommodating the refill 80, and a connecting member 40 that connects the first storage chamber C1 and the second storage chamber C2 and has a passage 42 through which the refill 80 can pass from the second storage chamber C2 toward the first storage chamber C1.

[0059] In a conventional mechanical pencil, a large number of refills could not be accommodated within the mechanical pencil. Therefore, simply by not replenishing the refills for a short period of time, the refills housed within the mechanical pencil would be used up, and there were cases where the mechanical pencil could not be used in important situations. This problem could also become a serious situation for users of the mechanical pencil. Also, in order to avoid such problems, it was necessary to carry around spare refills housed in a separate case along with the mechanical pencil, which sometimes imposed inconvenience on the users.

[0060] According to the mechanical pencil 10 of the present embodiment, while restricting the number of refills 80 accommodated in the first storage chamber C1, a large number of refills 80 can be accommodated in the second storage chamber C2. Therefore, while suppressing the occurrence of clogging, the number of times of replenishing the refills 80 into the mechanical pencil 10 can be reduced. In particular, in the mechanical pencil 10 of the present embodiment, even if the refills 80 are not frequently replenished, the situation where the refills 80 housed in the mechanical pencil 10 are used up is suppressed. Therefore, the possibility of the situation where the mechanical pencil 10 cannot be used in important situations can be reduced. As a result, the user can use the mechanical pencil 10 with confidence. Also, since it is not always necessary to carry around spare refills housed in a separate case, the burden on the user is reduced.

[0061] According to the study by the inventors of the present case, in a conventional mechanical pencil, from the viewpoint of suppressing the occurrence of clogging, the upper limit of the number of refills that can be accommodated in the refill storage chamber was about 6. In the mechanical pencil 10 of the present embodiment, even if, for example, about 20 refills 80 are accommodated in the second storage chamber C2, the occurrence of clogging is sufficiently suppressed. Considering that it was impossible to suppress the occurrence of clogging while accommodating such a large number of refills in a conventional mechanical pencil, the above-described effect of the present embodiment can be said to be an extremely remarkable effect.

[0062] In the mechanical pencil 10 of the present embodiment, the passage 42 is positioned radially displaced by dr from the central axis A of the mechanical pencil 10.

[0063] According to such a mechanical pencil 10, when the passage 42 is positioned vertically downward with respect to the central axis A, the writing core 80 accommodated in the second accommodation chamber C2 is easily guided toward the passage 42 by the action of gravity. Therefore, the writing core 80 can be smoothly moved from the second accommodation chamber C2 toward the first accommodation chamber C1.

[0064] In the mechanical pencil 10 of the present embodiment, the passage 42 includes a hole 44d provided in the connecting member 40.

[0065] According to such a mechanical pencil 10, the writing core 80 accommodated in the second accommodation chamber C2 can smoothly move toward the first accommodation chamber C1 through the hole 44d.

[0066] In the mechanical pencil 10 of the present embodiment, the connecting member 40 has a main body portion 44 and a rear protruding portion 46 protruding rearward from the main body portion 44, and the passage 42 includes a groove 46b provided on the outer surface of the rear protruding portion 46.

[0067] According to such a mechanical pencil 10, the writing core 80 accommodated in the second accommodation chamber C2 can smoothly move toward the first accommodation chamber C1 through the groove 46b.

[0068] In the mechanical pencil 10 of the present embodiment, the connecting member 40 has guide portions 44e, 46c, 46d for guiding the writing core 80 to the passage 42.

[0069] According to such a mechanical pencil 10, when the front end of the writing core 80 accommodated in the second accommodation chamber C2 abuts against the guide portions 44e, 46c, 46d, the front end of the writing core 80 is guided by the guide portions 44e, 46c, 46d and moves into the passage 42. Therefore, the writing core 80 accommodated in the second accommodation chamber C2 can move more smoothly toward the first accommodation chamber C1.

[0070] The mechanical pencil 10 of the present embodiment has a clip 28, and the passage 42 is located on the side opposite to the clip 28 with respect to the central axis A of the mechanical pencil 10.

[0071] When writing with the mechanical pencil 10, the user often holds the mechanical pencil 10 with the clip 28 facing upward. In this case, the passage 42 located on the side opposite to the clip 28 with respect to the central axis A will be located vertically downward with respect to the central axis A. According to the mechanical pencil 10 of the present embodiment, even if the user does not consciously position the passage 42 downward with respect to the central axis A, just by holding the mechanical pencil 10 with the clip 28 facing upward, the passage 42 can be positioned downward with respect to the central axis A.

[0072] The mechanical pencil 10 of the present embodiment includes a storage chamber C1 capable of storing the writing core 80, and a retreat space S located behind the storage chamber C1 and in which the writing core 80 in the storage chamber C1 can retreat. The dimension of the retreat space S in the direction orthogonal to the central axis A is smaller than the dimension of the storage chamber C1 in the direction orthogonal to the central axis A.

[0073] When retracting the writing core 80 that protrudes significantly from the tip of the mechanical pencil 10, or when inserting the writing core 80 while retracting it from the tip side of the mechanical pencil 10, another writing core 81 may be pinched between the rear end of the retracted writing core 80 and the rear end of the first storage chamber (storage chamber) C1, and there is a risk that the other writing core 81 may break. The broken writing core 81 moves to the front part of the first storage chamber C1 during writing. In this case, when the writing core 80 in use is consumed, the broken writing core 81 may prevent the other writing core 80 from moving forward, causing so-called core jamming.

[0074] According to the mechanical pencil 10 of the present embodiment, when retracting the refill 80 that protrudes significantly from the tip of the mechanical pencil 10, or when inserting the refill 80 while retracting it from the tip side of the mechanical pencil 10, if another refill 81 is pressed backward by the retracted refill 80, the pressed other refill 81 can retract into the retraction space S. Thereby, another refill 81 is sandwiched between the rear end of the retracted refill 80 and any member in the storage chamber, for example, the rear end portion of the first storage chamber C1, and it is possible to suppress the other refill 81 from breaking. Therefore, it is possible to effectively suppress the broken refill 81 from moving to the front portion of the first storage chamber C1 during writing and causing clogging due to this refill 81.

[0075] Further, since the dimension in the direction orthogonal to the central axis A in the retraction space S is smaller than the dimension in the direction orthogonal to the central axis A in the first storage chamber C1, the volume occupied by the retraction space S can be reduced. Therefore, it becomes possible to effectively utilize the space inside the mechanical pencil 10.

[0076] In the mechanical pencil 10 of the present embodiment, the dimension in the direction orthogonal to the central axis A in the retraction space S is smaller than 1 / 2 of the dimension in the direction orthogonal to the central axis A in the storage chamber C1.

[0077] According to such a mechanical pencil 10, the volume occupied by the retraction space S can be further reduced. Therefore, it becomes possible to further effectively utilize the space inside the mechanical pencil 10.

[0078] In the mechanical pencil 10 of the present embodiment, the central axis A of the retraction space S coincides with the central axis A of the storage chamber C1.

[0079] According to such a mechanical pencil 10, it is possible to appropriately retract another refill 81 that is pressed backward by the rear end of the refill 80 retracted along the central axis of the storage chamber C1.

[0080] The mechanical pencil 10 of the present embodiment includes a connection member 40 connected to the rear end of the storage chamber C1, and a pipe member 50 connected to the connection member 40 from the rear. The space inside the pipe member 50 forms at least a part of the evacuation space S.

[0081] According to such a mechanical pencil 10, the evacuation space S can be formed with a simple configuration.

[0082] In the mechanical pencil 10 of the present embodiment, the rear end of the evacuation space S is closed.

[0083] According to such a mechanical pencil 10, when the user replenishes the refill 80 in the second storage chamber C2, it is possible to prevent the refill 80 to be replenished from accidentally entering the evacuation space S.

Explanation of reference numerals

[0084] 10 Mechanical pencil 20 Shaft cylinder 22 Shaft cylinder body 24 Tip member 25 Sleeve 26 Connecting member 28 Clip 30 Core operation unit 32 First core pipe 34 Second core pipe 36 Eraser 38 Cap 40 Connecting member 42 Passage 44d Hole 46b Groove 44 Body part 44a First contact part 44b Second contact part 44c Inner inclined surface 44d Hole 44e Groove 46 Rear protruding part 46a Third contact part 46b Groove 46b1 Bottom surface 46b2 Side surface 46c First inclined surface 46d Second inclined surface 46e Rear end surface 50 Pipe member 61 Chuck 62 Elastic member 63 Receiving member 64 Fastening tool 65 Core holder 80 Writing core 81 Writing core 90 Writing surface A Central axis C1 First accommodation chamber C2 Second accommodation chamber S Retreating space da Axial direction dr Radial direction dc Circumferential direction

Claims

1. a first accommodation chamber capable of accommodating a refill; a second accommodation chamber located behind the first accommodation chamber and capable of accommodating a refill; a connecting member that connects the first accommodation chamber and the second accommodation chamber and has a passage through which the refill can pass from the second accommodation chamber to the first accommodation chamber; the connecting member has a main body portion and a rear protruding portion protruding rearward from the main body portion; the passage includes a groove provided on the outer surface of the rear protruding portion, a mechanical pencil.

2. The mechanical pencil according to claim 1, wherein the passage is located radially offset from the central axis of the mechanical pencil.

3. The mechanical pencil according to claim 1 or 2, wherein the passage includes a hole provided in the connecting member.

4. The mechanical pencil according to any one of claims 1 to 3, wherein the connecting member has a guide portion for guiding the refill into the passage.

5. having a clip; The mechanical pencil according to any one of claims 1 to 4, wherein the passage is located on the side opposite to the clip with respect to the central axis of the mechanical pencil.

6. an accommodation chamber capable of accommodating a refill; a retraction space located behind the accommodation chamber and into which the refill in the accommodation chamber can retract; a mechanical pencil, wherein a dimension in a direction orthogonal to the central axis in the retraction space is smaller than a dimension in a direction orthogonal to the central axis in the accommodation chamber.

7. The mechanical pencil according to claim 6, wherein a dimension in a direction orthogonal to the central axis in the retraction space is smaller than 1 / 2 of a dimension in a direction orthogonal to the central axis in the accommodation chamber.

8. The mechanical pencil according to claim 6 or 7, wherein the central axis of the retraction space coincides with the central axis of the accommodation chamber.

9. a connecting member connected to the rear end of the accommodation chamber; a pipe member connected to the connecting member from the rear; The mechanical pencil according to any one of claims 6 to 8, wherein the space inside the pipe member forms at least a part of the retraction space.

10. The mechanical pencil according to any one of claims 6 to 9, wherein the rear end of the retraction space is closed.

Images