Mechanical pencil

Abstract

To provide a mechanical pencil with the rotation drive mechanism that can be freely switched on and off.SOLUTION: A mechanical pencil 1 is configured so that back and forth movement of a chuck unit 20 arranged in a barrel 11 releases and grips a writing core so as to extend the writing core forward. The chuck unit 20 is held in the barrel 11 so as to be rotatable around a central axis while holding the writing core. The mechanical pencil comprises: a rotation drive mechanism 22 which has a rotor 30, and in which the rotor 30 retracts as the chuck unit 20 retracts due to writing pressure received by the writing core, causing the rotor 30 to rotate, and the rotational movement of the rotor 30 is configured to be transmitted to the writing core via the chuck unit 20; and further a rotation lock mechanism that locks the rotation of the rotor 30.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a mechanical pencil. [Background technology]

[0002] A mechanical pencil is known which is equipped with a rotating member including a slider equipped with a chuck that allows the writing lead to move forward and prevents it from moving backward, and a rotation drive mechanism which has a rotor and rotates the rotor in one direction in response to the axial backward movement caused by the writing pressure applied to the writing lead held by the chuck and the axial forward movement caused by the release of the writing pressure, and in which the chuck rotates in response to the rotational drive force of the rotor, causing the writing lead to rotate (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2007 / 142135 Summary of the Invention [Problem to be solved by the invention]

[0004] In the mechanical pencil described in Patent Document 1, the writing lead rotates as writing progresses, which can prevent uneven wear of the writing lead. On the other hand, since the writing lead is rotated by the rotary drive mechanism, the writing lead also moves forward and backward, albeit slightly, and this forward and backward movement of the writing lead can be bothersome, for example, when taking shorthand notes. Therefore, it is preferable that the user be able to freely switch the rotary drive mechanism between on (operating or enabled) and off (stopped or disabled).

[0005] An object of the present invention is to provide a mechanical pencil in which the rotation drive mechanism can be freely switched on and off. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a mechanical pencil configured to advance the writing lead forward by releasing and gripping the writing lead by the back and forth movement of a chuck unit arranged within a barrel, and the chuck unit is held within the barrel so that it can rotate about a central axis while gripping the writing lead, the mechanical pencil having a rotor, the rotor retracting as the chuck unit retracts due to the writing pressure received by the writing lead, and a rotation drive mechanism for rotating the rotor is provided, and the rotational motion of the rotor is transmitted to the writing lead via the chuck unit, and the mechanical pencil is characterized in that it further comprises a rotation lock mechanism for locking the rotation of the rotor.

[0007] According to another aspect of the present invention, the rotation lock mechanism may be configured to lock the rotor in a relatively retreated state in the rotation drive mechanism. The rotation lock mechanism may be configured to press the rotor backward or press the rotation drive mechanism forward to cause the rotor to retreat relatively in the rotation drive mechanism.

[0008] The rotor or the rotation drive mechanism may be pressed directly or indirectly by the rotation lock mechanism. The rotation lock mechanism may have a rotating member equipped with a cam, and the rotational motion of the rotating member may be converted into linear motion by the action of the cam to press the rotor.

[0009] The rotor may be pressed rearward via the chuck unit. The rotation lock mechanism may have a retractable mechanism or a rotation extending mechanism that presses the rotation drive mechanism forward.

[0010] The extension / retraction mechanism or the rotary extension mechanism may have a spring and a sliding member that biases the spring, and the sliding member may be advanced to press the rotary drive mechanism forward.

[0011] The retractable mechanism may further include a knock member and a knock rotor disposed at a rear end of the barrel, and when a knock operation of the knock member is performed to advance the knock rotor to a predetermined position, the knock rotor rotates about a central axis, and the backward movement of the knock rotor is locked, and the rotation drive mechanism is advanced so that the rotor is locked in a relatively backward state in the rotation drive mechanism. The rotor may be pressed backward via a spacer.

[0012] The writing lead may be advanced by moving the chuck unit back and forth while the rotation lock mechanism locks the rotor. The rotation drive mechanism has a first cam forming member and a second cam forming member, the rotor is formed in an annular shape with a first cam surface and a second cam surface formed on one end face and the other end face in the axial direction, respectively, and a first fixed cam surface and a second fixed cam surface formed on the first cam forming member and the second cam forming member are arranged so as to face the first cam surface and the second cam surface, respectively, and the first cam surface of the rotor comes into contact with and meshes with the first fixed cam surface by the retreating movement of the chuck unit due to the writing pressure, and the second cam surface of the rotor comes into contact with the second fixed cam surface by the release of the writing pressure. The rotor may be configured to abut against and mesh with the first fixed cam surface, and when the first cam surface of the rotor is meshed with the first fixed cam surface, the second cam surface of the rotor and the second fixed cam surface are set in a phase-shifted relationship with respect to one tooth of the cam in the axial direction, and when the second cam surface of the rotor is meshed with the second fixed cam surface, the first cam surface of the rotor and the first fixed cam surface are set in a phase-shifted relationship with respect to one tooth of the cam in the axial direction, and the rotation drive mechanism may mesh the first cam surface of the rotor with the first fixed cam surface to lock the rotor. Effect of the Invention

[0013] According to the aspects of the present invention, a common effect is achieved in that a mechanical pencil is provided in which the rotation drive mechanism can be freely switched on and off. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a front view of the first mechanical pencil. [Diagram 2] FIG. 2 is a vertical cross-sectional view of the first mechanical pencil. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of the rotation drive mechanism. [Figure 4] FIG. 4 is a schematic diagram illustrating the rotational drive of the rotor of the rotational drive mechanism. [Diagram 5] FIG. 5 is a schematic diagram illustrating the rotational drive of the rotor, following FIG. [Figure 6] FIG. 6 is a vertical cross-sectional view of the rear shaft of the first mechanical pencil. [Figure 7] FIG. 7 is an exploded perspective view of the changeover switch and the first rotating member. [Figure 8] FIG. 8 is a vertical cross-sectional view illustrating the operation of the first rotation lock mechanism. [Figure 9] FIG. 9 is a vertical cross-sectional view of the second mechanical pencil. [Figure 10] FIG. 10 is a vertical cross-sectional view illustrating the operation of the second rotation lock mechanism. [Figure 11] FIG. 11 is a vertical cross-sectional view of the third mechanical pencil. [Figure 12] FIG. 12 is a vertical cross-sectional view of the rear end portion of the rear barrel of the third mechanical pencil. [Figure 13] FIG. 13 is a perspective view of a knock member of the third mechanical pencil. [Figure 14] FIG. 14 is a perspective view of a knock rotor of the third mechanical pencil. [Figure 15] FIG. 15 is a schematic diagram illustrating the operation of the third rotation lock mechanism. [Figure 16] FIG. 16 is a vertical cross-sectional view illustrating the operation of the third rotation lock mechanism. [Figure 17] FIG. 17 is a vertical cross-sectional view illustrating the operation of the fourth rotation lock mechanism. [Figure 18]FIG. 18 is a vertical cross-sectional view of the first ballpoint pen in a non-writing state. [Figure 19] FIG. 19 is a vertical cross-sectional view of the rear end portion of the rear barrel of the first ballpoint pen. [Figure 20] FIG. 20 is a perspective view of the third rotating member of the first ballpoint pen. [Figure 21] FIG. 21 is a perspective view of the first sliding member of the first ballpoint pen. [Figure 22] FIG. 22 is a perspective view of the first ballpoint pen in a non-writing state. [Diagram 23] FIG. 23 is a perspective view of the first ballpoint pen in a writing state. [Figure 24] FIG. 24 is a cross-sectional view illustrating the operation of the first rotation and delivery mechanism. [Diagram 25] FIG. 25 is a vertical cross-sectional view of the fourth mechanical pencil. [Figure 26] FIG. 26 is a vertical cross-sectional view of the rear end portion of the rear barrel of the fourth mechanical pencil. [Figure 27] FIG. 27 is a perspective view of a fourth rotating member of the fourth mechanical pencil. [Figure 28] FIG. 28 is a perspective view of the second sliding member of the fourth mechanical pencil. [Figure 29] FIG. 29 is a cross-sectional view illustrating the operation of the second rotational delivery mechanism. [Diagram 30] FIG. 30 is a vertical cross-sectional view illustrating the operation of the fifth rotation lock mechanism and the second rotation extension mechanism. [Diagram 31] FIG. 31 is a vertical sectional view illustrating the operation of the sixth rotation lock mechanism. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Corresponding components throughout the drawings are designated by common reference numerals.

[0016] FIG. 1 is a front view of the first mechanical pencil 1, and FIG. 2 is a vertical cross-sectional view of the first mechanical pencil 1. As shown in FIG.

[0017] The first mechanical pencil 1 has a barrel 11 formed in a cylindrical shape. The barrel 11 has a front barrel 12, a rear barrel 40 that fits or screws onto the rear end of the front barrel 12, and a tip member 14 that fits or screws onto the front end of the front barrel 12. The first mechanical pencil 1 is configured so that a writing lead protrudes from a tip pipe 16 provided at the tip of the tip member 14. In this specification, in the axial direction of the first mechanical pencil 1, the writing lead side is defined as the "front" side, and the opposite side to the writing lead side is defined as the "rear" side.

[0018] A rectangular through hole 43 extending in the circumferential direction is provided on the front side of the rear barrel 40. A switch portion 52 of a changeover switch 50 protrudes from the through hole 43. A knock cover 15 is attached to the rear end of the rear barrel 40, covering an eraser 17 as an erasing member. A slider 18 is disposed inside the front end of the barrel 11 so as to be slidable in the axial direction and rotatable about the central axis. A tip pipe 16 is attached to the slider 18. A retaining chuck 19 with a through hole formed in the center is disposed inside the slider 18 behind the tip pipe 16. The through hole of the retaining chuck 19 comes into sliding contact with the outer peripheral surface of the writing lead, and acts to temporarily hold the writing lead.

[0019] A chuck unit 20 that grips the writing lead and a cylindrical relay member 21 are connected to the rear end of the slider 18. When writing pressure is applied to the writing lead, the chuck unit 20 grips the writing lead and prevents the writing lead from moving backward, and when a force is applied to pull the writing lead forward, the writing lead can be pulled forward without resistance.

[0020] The chuck unit 20 and the relay member 21 can move together in the axial direction with the slider 18. The rear end of the relay member 21 is connected to a rotation drive mechanism 22. The front end of a lead case 23 is fitted onto the outer circumferential surface of the rear end of the chuck unit 20. The lead case 23 is formed in a cylindrical shape and contains a writing lead therein.

[0021] A knock member 24 is provided inside the rear end of the barrel 11, specifically the rear end of the rear barrel 40, so as to be movable back and forth relative to the barrel 11. The knock member 24 is biased rearward by a coil spring 25. The eraser 17 is removably attached inside the rear end of the knock member 24. The above-mentioned knock cover 15 is removably attached to the outer circumferential surface of the rear end of the knock member 24 to protect the eraser 17 from dirt and the like.

[0022] By performing a knock operation that presses the knock member 24 or the knock cover 15 forward, the lead case 23 moves forward. This also moves the writing lead forward via the chuck unit 20, acting to feed the writing lead from the tip pipe 16. When the pressure caused by the knock operation is released, the knock member 24 retreats and returns to its original position due to the biasing force of the coil spring 25. At this time, the writing lead is held by the retaining chuck 19 arranged inside the slider 18, and the chuck unit 20 acts to pull the writing lead out of the chuck unit 20 without resistance. As a result, the writing lead is fed out from the tip pipe 16, and a predetermined amount of the writing lead can be fed out each time the knock operation is repeated.

[0023] 3 is an enlarged cross-sectional view of the rotation drive mechanism 22. The rotation drive mechanism 22 is disposed in the internal space of the rear axle 40. The rotation drive mechanism 22 is connected to the rear end of the relay member 21. Axle spring 26 is disposed between the rear end surface of the front axle 12 and the front end surface of the rotation drive mechanism 22, and the rotation drive mechanism 22 is biased rearward. The rear end surface of the rotation drive mechanism 22 abuts against a front end surface 42 of a regulating protrusion 41 of the rear axle 40, which will be described later, and the core case 23 passes through the interior of the relay member 21 and the rotation drive mechanism 22, and is separated from the rotation drive mechanism 22.

[0024] The rotation drive mechanism 22 has a rotor 30 formed in a cylindrical shape, an upper cam forming member 31 which is a first cam forming member formed in a cylindrical shape, a lower cam forming member 32 which is a second cam forming member formed in a cylindrical shape, a cylinder member 33 which is formed in a cylindrical shape, a torque canceller 34 which is also formed in a cylindrical shape, and a coil-shaped cushion spring 35. The rotation drive mechanism 22 is a unit formed by integrating these members.

[0025] In addition, a first rotation lock mechanism having a changeover switch 50 and a first rotation member 54 is disposed in front of the rotation drive mechanism 22, as will be described later.

[0026] The outer peripheral surface of the rear end of relay member 21 is fitted onto the inner peripheral surface of the front end of rotor 30. The rotor 30 has a flange-shaped portion with a slightly larger diameter near the front end, with first cam surface 30a formed on the rear end surface of said portion and second cam surface 30b formed on the front end surface of said portion.

[0027] The upper cam forming member 31 rotatably surrounds the rotor 30 behind the first cam surface 30a of the rotor 30. The lower cam forming member 32 fits onto the outer peripheral surface of the front end portion of the upper cam forming member 31. A first fixed cam surface 31a is formed on the front end surface of the upper cam forming member 31 facing the first cam surface 30a of the rotor 30. A second fixed cam surface 32a is formed on the inner surface of the front end portion of the lower cam forming member 32 facing the second cam surface 30b of the rotor 30.

[0028] A cylindrically shaped cylinder member 33 is fitted onto the outer peripheral surface of the rear end of the upper cam forming member 31. An insertion hole 33a is formed in the rear end of the cylinder member 33, through which the lead case 23 can be inserted. A cylindrically shaped torque canceller 34 that is movable back and forth is disposed within the cylinder member 33. A cushion spring 35 is disposed between the inner surface of the front end of the torque canceller 34 and the inner surface of the rear end of the cylinder member 33. The cushion spring 35 urges the rotor 30 forward via the torque canceller 34.

[0029] Here, relay member 21 transmits the backward and forward movement (cushioning movement) of the writing lead based on the writing action to rotation drive mechanism 22, i.e., rotor 30, and also transmits the rotational motion of rotor 30 in rotation drive mechanism 22 caused by the cushioning movement to chuck unit 20 in a state where it is gripping the writing lead. Therefore, the writing lead held by chuck unit 20 also rotates.

[0030] When the first mechanical pencil 1 is not being used for writing, i.e., when no writing pressure is being applied to the writing lead, the rotor 30 is positioned forward by the biasing force of the cushion spring 35 via the torque canceller 34. Therefore, the second cam surface 30b of the rotor 30 abuts against the second fixed cam surface 32a and is brought into an engaged state. When the first mechanical pencil 1 is used for writing, i.e., when writing pressure is being applied to the writing lead, the chuck unit 20 moves backward against the biasing force of the cushion spring 35, and the rotor 30 also moves backward accordingly. Therefore, the first cam surface 30a of the rotor 30 abuts against the first fixed cam surface 31a and is brought into an engaged state.

[0031] Fig. 4 is a schematic diagram for explaining the rotational drive of rotor 30 of rotation drive mechanism 22, and Fig. 5 is a schematic diagram for explaining the rotational drive of rotor 30 subsequent to Fig. 4. In Figs. 4 and 5, a first cam surface 30a having a sawtooth shape continuously along the circumferential direction is formed in an annular shape on the rear end surface, which is the upper surface of rotor 30, and a second cam surface 30b having a sawtooth shape continuously along the circumferential direction is formed in an annular shape on the front end surface, which is the lower surface of rotor 30.

[0032] A first fixed cam surface 31a having a continuous sawtooth shape along the circumferential direction is also formed on an annular end face of the upper cam forming member 31 facing the first cam surface 30a of the rotor 30, and a second fixed cam surface 32a having a continuous sawtooth shape along the circumferential direction is also formed on an annular end face of the lower cam forming member 32 facing the second cam surface 30b of the rotor 30. The cam surfaces of the first cam surface 30a and the second cam surface 30b formed on the rotor 30 and the cam surfaces of the first fixed cam surface 31a formed on the upper cam forming member 31 and the second fixed cam surface 32a formed on the lower cam forming member 32 are formed so that their pitches are substantially the same.

[0033] 4(A) shows the relationship between the rotor 30, the upper cam forming member 31, and the lower cam forming member 32 when no writing pressure is applied to the writing lead. In this state, the second cam surface 30b formed on the rotor 30 is in contact with the second fixed cam surface 32a of the lower cam forming member 32 by the biasing force of the cushion spring 35. At this time, the first cam surface 30a of the rotor 30 and the first fixed cam surface 31a of the upper cam forming member 31 are set to be shifted by half a phase (half a pitch) with respect to one tooth of the cam in the axial direction.

[0034] 4(B) shows an initial state in which writing pressure is applied to the writing lead for writing with the first mechanical pencil 1. In this state, the rotor 30 moves backward by contracting the cushion spring 35 as the chuck unit 20 moves backward. This causes the rotor 30 to move toward the first fixed cam surface 31a of the upper cam forming member 31.

[0035] 4(C) shows a state in which further writing pressure is applied to the writing lead, causing the rotor 30 to abut against the first fixed cam surface 31a of the upper cam forming member 31 and move backward. In this state, the first cam surface 30a of the rotor 30 meshes with the first fixed cam surface 31a of the upper cam forming member 31. As a result, the rotor 30 receives a rotational drive equivalent to a half phase (half pitch) of one tooth of the first cam surface 30a.

[0036] 4 and 5, a circle drawn in the center of the rotor 30 indicates the amount of rotational movement of the rotor 30. In the state shown in Fig. 4(C), the second cam surface 30b of the rotor 30 and the second fixed cam surface 32a of the lower cam forming member 32 are set to have a relationship shifted by half a phase (half a pitch) with respect to one tooth of the cam in the axial direction.

[0037] 5(D) shows the initial state when writing with the first mechanical pencil 1 is finished and the writing pressure on the writing lead is released. In this case, the rotor 30 moves forward due to the biasing force of the cushion spring 35. This causes the rotor 30 to move toward the lower cam forming member 32.

[0038] Next, in FIG. 5(E), the rotor 30 is rotated by the biasing force of the cushion spring 35. The second fixed cam surface 32a of the lower cam forming member 32 In this case, the second cam surface 30b of the rotor 30 meshes with the second fixed cam surface 32a of the lower cam forming member 32. As a result, the rotor 30 is again subjected to a rotational drive equivalent to a half phase (half pitch) of one tooth of the second cam surface 30b.

[0039] Therefore, as indicated by the circle drawn in the center of the rotor 30, as the rotor 30 receives writing pressure and reciprocates in the axial direction, i.e., moves back and forth, the rotor 30 is rotationally driven by one tooth (one pitch) of the first cam surface 30a and the second cam surface 30b, and the writing lead held by it is similarly rotationally driven via the chuck unit 20. Therefore, by one back and forth movement of the rotor 30 in the axial direction due to writing, the rotor 30 is subjected to a rotational movement corresponding to one tooth of the cam, and by repeating this, the writing lead is sequentially rotationally driven. Therefore, it is possible to prevent uneven wear of the writing lead as writing proceeds, and to prevent large changes in the thickness and darkness of the drawn lines.

[0040] The torque canceller 34, which pushes the rotor 30 forward by receiving the biasing force of the cushion spring 35, generates a slip between its front end face and the rear end face of the rotor 30, preventing the rotational motion of the rotor 30 from being transmitted to the cushion spring 35. In other words, the torque canceller 34 prevents the rotational motion of the rotor 30 from being transmitted to the cushion spring 35, thereby preventing the cushion spring 35 from twisting back (torque) that would impede the rotational motion of the rotor 30.

[0041] As described above, the first mechanical pencil 1 has a chuck unit 20 and a rotor 30, and is configured so that the chuck unit 20 moves back and forth to release and grip the writing lead, thereby allowing the writing lead to be advanced forward. The chuck unit 20 is held within the barrel 11 so that it can rotate about the central axis while gripping the writing lead. The rotor 30 retracts as the chuck unit 20 retracts due to the writing pressure received by the writing lead, and the first mechanical pencil 1 is equipped with a rotational drive mechanism 22 which causes the rotor 30 to rotate, and the rotational motion of the rotor 30 is transmitted to the writing lead via the chuck unit 20.

[0042] Here, the principle of the rotation lock mechanism that enables the user to freely switch the rotation drive mechanism between on (operating or enabled) and off (stopped or disabled) will be described.

[0043] The rotor 30 is biased forward by the biasing force of the cushion spring 35 via the torque canceller 34. Therefore, when no writing pressure is applied to the writing core, the second cam surface 30b of the rotor 30 meshes with the second fixed cam surface 32a of the lower cam forming member 32, as shown in FIG. 4(A). The rotation lock mechanism is configured to mesh the first cam surface 30a of the rotor 30 with the first fixed cam surface 31a of the upper cam forming member 31, as shown in FIG. 4(C), when no writing pressure is applied to the writing core. As a result, even if writing pressure is applied to the writing core, the rotor 30 retreats and does not rotate. Therefore, the rotation of the rotor 30 is locked by the rotation lock mechanism.

[0044] A specific configuration of the rotation lock mechanism will now be described.

[0045] FIG. 6 is a vertical cross-sectional view of the rear shaft 40 of the first mechanical pencil 1. In FIG. 6, the upper side is the rear side of the first mechanical pencil 1. The above-mentioned through hole 43 is provided on the side surface on the front side of the rear shaft 40. The inner peripheral surface of the rear shaft 40 is provided with an inclined cam receiving surface 44 that extends obliquely along the circumferential direction around the central axis and faces forward. A plurality of regulating protrusions 41 extending along the axial direction are provided at equal intervals along the circumferential direction behind the inclined cam receiving surface 44. The front end surface 42 of the regulating protrusions 41 regulates the retreat of the rotation drive mechanism 22.

[0046] 7 is an exploded perspective view of the changeover switch 50 and the first rotating member 54. The changeover switch 50 has a C-shaped switch support portion 51 and a switch portion 52. The switch portion 52 is provided on the outer surface of one end of the curved switch support portion 51 so as to protrude outward.

[0047] The first rotating member 54 has a cylindrical cam body 55 having a C-shaped cross section, and a support plate 57 that partially closes a front opening 56 of the cam body 55. Because the cam body 55 has a C-shaped cross section, a gap 58 extending in the axial direction is defined on the side surface of the cam body 55. An inclined cam surface 59 is provided on the rear end surface of the cam body 55. The inclined cam surface 59 is formed to correspond to the inclined cam receiving surface 44 of the rear axle 40.

[0048] In the axle tube 11, the changeover switch 50 is inserted into an opening 56 in the front of the first rotating member 54 and is disposed so as to abut against a support plate 57. At this time, the switch portion 52 of the changeover switch 50 is inserted into a gap 58 of the first rotating member 54. The width of the switch portion 52 is set to be slightly smaller than the width of the gap 58. As shown in FIG. 1, the switch portion 52 protrudes to the outside through the through hole 43 of the rear axle 40. In FIG. 1, the switch portion 52 is located on the left side of the through hole 43, but as will be described next, the switch portion 52 can be slid to be located on the right side of the through hole 43.

[0049] FIG. 8 is a vertical cross-sectional view explaining the operation of the first rotation lock mechanism. The state shown in FIG. 8(A) is a rotation unlocked state in which the rotation drive mechanism 22 is on, and the state shown in FIG. 8(B) is a rotation locked state in which the rotation drive mechanism 22 is off. Therefore, the rotation drive mechanism 22 shown in FIG. 8(A) corresponds to the state of the rotor 30 shown in FIG. 4(A). The state shown in FIG. 8(A) corresponds to the state of the switch unit 52 shown in FIG. 1. On the other hand, the rotation drive mechanism 22 shown in FIG. 8(B) corresponds to the state of the rotor 30 shown in FIG. 4(C), so that the first cam surface 30a of the rotor 30 and the first fixed cam surface 31a of the upper cam forming member 31 are engaged with each other.

[0050] In the vertical cross-sectional view of Fig. 8(A), the switch unit 52 is not shown. In the vertical cross-sectional view of Fig. 8(A), the inclined cam surface 59 of the first rotating member 54 shown at the bottom abuts against the inclined cam receiving surface 44 of the rear axle 40, but the inclined cam surface 59 of the first rotating member 54 shown at the top does not abut against the inclined cam receiving surface 44 of the rear axle 40. On the other hand, in the vertical cross-sectional view of Fig. 8(B), all of the inclined cam surfaces 59 of the first rotating member 54 abut against the inclined cam receiving surface 44 of the rear axle 40. That is, the changeover switch 50 and the first rotating member 54 shown in Fig. 8(A) are disposed rearward in the axle tube 11 from the changeover switch 50 and the first rotating member 54 shown in Fig. 8(B).

[0051] From the state shown in FIG. 8(A), by operating the changeover switch 50, specifically, by sliding the switch portion 52 with a finger along the circumferential direction in FIG. 1 to move it from left to right in the through hole 43, the first rotating member 54 is rotated around the central axis together with the changeover switch 50. Here, the changeover switch 50 and the first rotating member 54 are always biased backward by the shaft spring 26. Therefore, the inclined cam surface 59 of the first rotating member 54 slides while abutting along the inclined cam receiving surface 44 of the rear axle 40, and the changeover switch 50 and the first rotating member 54 move backward by a distance D in response to the slide. As a result, the first rotating member 54, specifically the rear end surface of the support plate 57, presses the front end surface of the rotor 30, causing the rotor 30 to move backward. By the rotor 30 moving backward, the rotor 30 is brought into the state shown in FIG. 4(C), and the rotation of the rotor 30 is locked.

[0052] On the other hand, by operating the changeover switch 50 from the state shown in FIG. 8(B), specifically, by sliding the switch portion 52 with a finger along the circumferential direction in FIG. 1 to move it from right to left in the through hole 43, the first rotating member 54 is rotated in the reverse direction around the central axis together with the changeover switch 50. As a result, the inclined cam surface 59 of the first rotating member 54 slides in the reverse direction while abutting along the inclined cam receiving surface 44 of the rear axle 40. In response to the slide, the changeover switch 50 and the first rotating member 54 advance by a distance D against the biasing force of the shaft spring 26, and reach the state shown in FIG. 8(A). As the changeover switch 50 and the first rotating member 54 advance, the rotor 30 advances due to the biasing force of the cushion spring 35. As the rotor 30 advances, the rotor 30 reaches the state shown in FIG. 4(A), and the lock on the rotation of the rotor 30 is released. The through hole 43 of the rear axle 40 is formed slightly larger than the shape of the switch portion 52 of the change-over switch 50 so as not to impede the forward or backward movement of the switch portion 52.

[0053] In the first rotation lock mechanism, the changeover switch 50 and the first rotating member 54 may be configured in any manner as long as they can convert rotational motion into linear motion and press or release the rotor 30 by the first rotating member 54 in response to the operation of the changeover switch 50. For example, the changeover switch 50 and the first rotating member 54 may be configured as an integral unit. In addition, the shapes of the inclined cam receiving surface 44 of the rear axle 40 and the inclined cam surface 59 of the first rotating member 54 may also be configured in any manner as long as they cooperate with each other.

[0054] In the first rotation lock mechanism, the changeover switch 50 is slid in the circumferential direction so as to rotate the first rotating member 54, but the changeover switch may be slid in the axial direction to more directly advance or retreat the rotor 30. In this case, the changeover switch may be made to be able to selectively switch between an advanced position where the rotor 30 is pressed inside the shaft cylinder 11 and a retreated position where the pressure on the rotor 30 is released.

[0055] It should be noted that the other rotation lock mechanisms described below do not have the changeover switch 50 and the first rotation member 54. Therefore, the shaft spring 26 directly biases the rotation drive mechanism 22 rearward.

[0056] 9 is a vertical cross-sectional view of the second mechanical pencil 2, and FIG. 10 is a vertical cross-sectional view explaining the operation of the second rotation lock mechanism. Compared to the first mechanical pencil 1, the second mechanical pencil 2 has a second rotation lock mechanism instead of the first rotation lock mechanism. Therefore, the inclined cam receiving surface 44 and the like are not provided on the inner surface of the rear shaft 13. The second rotation lock mechanism has a second rotating member 60 and an annular elastic member 65.

[0057] The second rotating member 60 is fitted to the outer peripheral surface of the tip member 14. A spiral cam groove 61 is provided on the inner peripheral surface of the second rotating member 60. On the other hand, a corresponding spiral cam protrusion 14a is provided on the outer peripheral surface of the tip member 14. In short, the cam groove 61 of the second rotating member 60 corresponds to a female screw, and the cam protrusion 14a of the tip member 14 corresponds to a male screw. Therefore, when the second rotating member 60 is rotated around the central axis relative to the tip member 14, the second rotating member 60 advances or retreats depending on the direction of rotation. An annular recess 18a is provided on the outer peripheral surface of the slider 18. An annular elastic member 65 is fitted to the annular recess 18a. The annular elastic member 65 is, for example, an O-ring.

[0058] 10(A) shows a state in which the rotation drive mechanism 22 is on and the rotation lock is released, and the state in which the rotation drive mechanism 22 is off and the rotation lock is released, and the state in which the rotation drive mechanism 22 is off and the rotation lock is released. In the state shown in FIG. 10(A), the second rotation member 60 is located in the front and does not interfere with the annular elastic member 65.

[0059] When the second rotating member 60 is rotated from this state, the cam groove 61 and the cam protrusion 14a cooperate to move the second rotating member 60 backward. As the second rotating member 60 moves backward, the annular elastic member 65 is pressed by the inclined surface 62 formed on the inner surface of the second rotating member 60 and moves backward, resulting in the state shown in FIG. 10(B). In detail, as the second rotating member 60 moves backward, the slider 18, and therefore the chuck unit 20 and the relay member 21, move backward by a distance D together with the annular elastic member 65. Since the rotor 30 is fitted to the rear end of the relay member 21, the rotor 30 moves backward, resulting in the state of the rotor 30 shown in FIG. 4(C), and the rotation of the rotor 30 is locked.

[0060] On the other hand, when the second rotating member 60 is rotated in the reverse direction, the cam groove 61 and the cam protrusion 14a cooperate to move the second rotating member 60 forward. As the second rotating member 60 moves forward, the pressure applied to the annular elastic member 65 by the inclined surface 62 of the second rotating member 60 is released, resulting in the state shown in Fig. 10(A). As a result, the rotor 30 moves forward, resulting in the state of the rotor 30 shown in Fig. 4(A), and the lock on the rotation of the rotor 30 is released.

[0061] In the second rotation lock mechanism, the second rotation member 60 and the annular elastic member 65 can be configured in any way as long as they can convert rotational motion into linear motion and can press or release the rotor 30 via the relay member 21. For example, the annular elastic member 65 and the slider 18 may be configured as one unit. In the second rotation lock mechanism, the second rotation member 60 is rotated to operate, but the annular elastic member 65 and thus the rotor 30 may be moved forward or backward more directly by sliding the fitting member fitted to the tip member 14 along the axial direction. In this case, the fitting member may be selectively switched between a forward position where the rotor 30 is pressed on the outer surface of the tip member 14 and a backward position where the pressure on the rotor 30 is released.

[0062] 11 is a vertical cross-sectional view of the third mechanical pencil 3. Compared to the first mechanical pencil 1, the third mechanical pencil 3 has a third rotation lock mechanism instead of the first rotation lock mechanism. The third rotation lock mechanism has a knock member 80, a knock rotor 90, and a biasing spring 99, and utilizes the retraction mechanism or the knock mechanism of a knock-type writing instrument. Therefore, the third rotation lock mechanism may be configured by applying a retraction mechanism other than the retraction mechanism described later.

[0063] Fig. 12 is a vertical cross-sectional view of the rear end portion of the rear barrel 70 of the third mechanical pencil 3. In Fig. 12, the upper side is the front side of the third mechanical pencil 3. The inner peripheral surface of the rear barrel 70 has four first protrusions 71 and four second protrusions 72 that extend in the axial direction and are connected to each other at the rear end portion. The first protrusions 71 and second protrusions 72 are arranged alternately at equal intervals along the circumferential direction.

[0064] The upper surface of each of the first protrusions 71, i.e., the surface facing the central axis of the rear axle 70, is provided with a cam surface 73 that is inclined in the circumferential direction with respect to a plane perpendicular to the front-rear direction and faces forward. Therefore, in the first protrusions 71, the rear of the cam surface 73 is thicker, i.e., a higher protrusion. On the other hand, in the first protrusions 71, the front of the cam surface 73 is thinner, i.e., a lower protrusion, and is a protrusion of the same height as the second protrusions 72. The front end surfaces 74 of the first protrusions 71 and the second protrusions 72 regulate the retreat of the rotation drive mechanism 22. Each of the first protrusions 71 and the second protrusions 72 has a vertical wall surface 75 that is a regulating surface that extends along the front-rear direction. An abutment surface 76 is formed on the front end surface of the portion connecting each of the first protrusions 71 and the second protrusions 72. The cam surface 73 and the vertical wall surface 75 constitute an outer cam 77.

[0065] FIG. 13 is a perspective view of the knock member 80 of the third mechanical pencil 3. In FIG. 13, the upper side is the front side of the third mechanical pencil 3. The knock member 80 is a cylindrical member with both ends open. Two protrusions 81 are provided at symmetrical positions on the outer peripheral surface of the front side of the knock member 80. In addition, a slit portion 82 extending rearward from the front end surface of the knock member 24 is provided between the two protrusions 81. Each of the protrusions 81 is configured to move back and forth between the first protrusions 71 by a knock operation. That is, the diameter of a circumscribing circle that includes the outer surfaces of the two protrusions 81 is set to be larger than the diameter of an inscribing circle that touches the upper surface of the first protrusion 71 of the rear barrel 70 and smaller than the diameter of an inscribing circle that touches the upper surface of the second protrusion 72 of the rear barrel 70. A cam surface 83 is formed on the front end surface of the knock member 80. The cam surface 83 has a peak portion 84 and a valley portion 85 that are formed symmetrically. The eight peaks 84 and valleys 85 are connected by slopes 86 .

[0066] FIG. 14 is a perspective view of the knock rotor 90 of the third mechanical pencil 3. In FIG. 14, the upper side is the front side of the third mechanical pencil 3. The knock rotor 90 is a cylindrical member with both ends open. The knock rotor 90 has a large diameter portion 90a and a small diameter portion 90b formed behind the large diameter portion 90a and inserted into the knock member 80 to be used for core alignment. The large diameter portion 90a has a larger diameter than the small diameter portion 90b. The outer peripheral surface of the large diameter portion 90a is formed with four vertical grooves 91 that are equally spaced along the circumferential direction and extend along the front-rear direction. The depth of the vertical grooves 91 is shallower than the difference in radius between the large diameter portion 90a and the small diameter portion 90b. The large diameter portion 90a is formed with an inner cam 92 consisting of four protrusions 92a defined by the four vertical grooves 91. A cam receiving surface 93 that is complementary to and cooperates with the cam surface 83 of the knock member 80 is formed around the entire circumference of the rear end surface of the large diameter portion 90a, radially inward from the inner cam 92. That is, the inner cam 92 and the cam receiving surface 93 are integrally provided on the large diameter portion 90a.

[0067] The cam receiving surface 93 is formed in a sawtooth shape and has an inclined surface 94 inclined in the circumferential direction with respect to a plane perpendicular to the front-rear direction. Every other inclined surface 94a of the eight inclined surfaces 94 is cut out by the vertical groove 91 described above. Adjacent inclined surfaces 94 between adjacent vertical grooves 91 are connected by a vertical wall surface 95 extending along the front-rear direction. That is, the cam receiving surface 93 has four vertical wall surfaces 95. Since the cam surface 83 of the knock member 80 and the cam receiving surface 93 of the knock rotor 90 are formed complementarily, a slope 94b inclined in the opposite direction to the slope 94 is provided in the portion of the vertical groove 91 and the acute angle portion defined by the slope 94 and the vertical wall surface 95. The slope 94b is provided with a height sufficient to cooperate with the cam surface 83 of the knock member 80, i.e., a length in the radial direction.

[0068] In short, a cam receiving surface 93 that cooperates with the cam surface 83 of the knock member 80 is provided on the radially inner side of the large diameter portion 90a, and an inner cam 92 that cooperates with the outer cam 77 of the rear shaft 70 is provided on the radially outer side of the large diameter portion 90a. The knock rotor 90 is provided with a through hole 96 along the central axis, and the lead case 23 is inserted into the through hole 96.

[0069] When the knock rotor 90 rotates about the central axis by a knock operation, the inner cam 92 engages with or disengages from the outer cam 77. That is, when the knock rotor 90 rotates about the central axis by a knock operation, the protrusion 92a of the inner cam 92 engages with the first protrusion 71 of the outer cam 77 or is disposed between the first protrusions 71 of the outer cam 77. When the protrusion 92a of the inner cam 92 is disposed between the first protrusions 71 of the outer cam 77, the first protrusion 71 of the outer cam 77 is disposed between the protrusions 92a of the inner cam 92, i.e., in the vertical groove 91.

[0070] The cam surface 83 of the knock member 80 and the cam receiving surface 93 of the knock rotor 90 are configured such that, when the inner cam 92 engages with or disengages from the outer cam 77, the peaks 84 of the cam surface 83 of the knock member 80 are positioned on the slopes 94 of the cam receiving surface 93 of the inner cam 92 in the circumferential direction. In other words, the slopes 86 of the cam surface 83 and the slopes 94 of the cam receiving surface 93 are positioned out of phase with each other. For this reason, when the slopes 86 of the cam surface 83 press the slopes 94 of the cam receiving surface 93 by a knock operation, the knock rotor 90 receives a circumferential component force due to the operating load and the biasing force of the biasing spring 99, and rotates about the central axis. On the other hand, the knock member 80 has a projection 81 that is in contact with the vertical wall surface of the outer cam 77. 75 The rotation about the central axis is restricted by the circumferential contact of the bearing 14 with the bearing 14. This operation will be described with reference to FIG.

[0071] FIG. 15 is a schematic diagram for explaining the operation of the third rotation lock mechanism, that is, the operation of the retraction mechanism, and is a schematic diagram showing the relationship between the cams of the third mechanical pencil 3. That is, FIG. 15 is a schematic diagram showing the positional relationship between the outer cam 77 of the rear barrel 70, the knock member 80, and the knock rotor 90. More specifically, the positions of the cam surface 83 of the knock member 80 and the cam receiving surface 93 of the knock rotor 90 are shown with respect to the outer cam 77 developed in the circumferential direction. In the figure, the upper side is the front side of the third mechanical pencil 3, and the lower side is the rear side of the third mechanical pencil 3. Also, FIG. 16 is a vertical cross-sectional view for explaining the operation of the third rotation lock mechanism.

[0072] The third rotation lock mechanism is operated by performing a knock operation to press the knock member 80 or the knock cover 15 forward, similar to the extending / retracting mechanism of a knock type writing instrument. Then, in the writing state of the knock type writing instrument, that is, the rotation locked state in which the knock rotor 90 is positioned forward, as shown in FIG. 16(B), the rotation drive mechanism is turned off. On the other hand, in the non-writing state of the knock type writing instrument, that is, the rotation unlocked state in which the knock rotor 90 is positioned backward, as shown in FIG. 16(A), the rotation drive mechanism is turned on. The knock rotor 90 is given a rotational force by a cam mechanism consisting of the cam surface 83 of the knock member 80 and the cam receiving surface 93 of the knock rotor 90, and the knock rotor 90 rotates with each knock operation as shown in FIG. In 15 Move from left to right.

[0073] The state shown in Fig. 15(A) is the same as the state shown in Fig. 16(A). In the state shown in Fig. 15(A), the inner cam 92 is not engaged with the outer cam 77. That is, the protrusions 92a of the inner cam 92 are disposed between the first protrusions 71 of the outer cam 77, and the first protrusions 71 of the outer cam 77 are disposed between the protrusions 92a of the inner cam 92, i.e., in the vertical grooves 91. The cam surface 83 and the cam receiving surface 93 are disposed out of phase with each other.

[0074] From this state, when the knock member 80 is pressed against the biasing force of the biasing spring 99 to move the knock member 80 and the knock rotor 90 forward, the rear end of the vertical groove 91 on the cam receiving surface 93 of the inner cam 92 passes over the front end of the first protrusion 71 of the outer cam 77 in the front-rear direction, as shown in Figure 15 (B). At this time, the inclined surface 94 of the cam receiving surface 93 of the knock rotor 90 and the cam surface 73 of the outer cam 77 coincide with each other, and the vertical wall surface of the first protrusion 71 of the outer cam 77 comes into contact with each other. 75 The restriction on the rotation of the knock rotor 90 about the central axis thereof by the knock rotor 90 is released.

[0075] 15(B), when the pressure on the knock member 80 is released, the knock member 80 and the knock rotor 90 move backward due to the biasing force of the biasing spring 99. At this time, the rotation of the knock rotor 90 about the central axis is not restricted by the vertical wall surface 75 of the first protrusion 71 of the outer cam 77. Therefore, when the biasing force of the biasing spring 99 causes the inclined surface 94 of the cam receiving surface 93 of the knock rotor 90 to press against the cam surface 73 of the outer cam 77 or the inclined surface 86 of the cam surface 83 of the knock member 80, the knock rotor 90 receives a circumferential component force and rotates about the central axis.

[0076] The backward movement and rotation of the knock rotor 90 are restricted by the engagement of the inner cam 92 with the outer cam 77. That is, the inclined surface 94 and the vertical wall surface 95 of the cam receiving surface 93 of the inner cam 92 are in contact with the cam surface 73 and the vertical wall surface 95 of the first protrusion 71 of the outer cam 77. 75 15C. By engaging with the knock rotor 90, the backward movement and rotation of the knock rotor 90 are restricted, resulting in the state shown in FIG. 15C.

[0077] The state shown in Fig. 15(C) is the same as Fig. 16(B). From this state, when the knock member 80 is pressed against the biasing force of the biasing spring 99 and the knock member 80 and the knock rotor 90 are advanced, the rear end of the vertical wall surface 95 of the cam receiving surface 93 of the inner cam 92 passes over the front end of the first protrusion 71 of the outer cam 77 in the front-rear direction, as shown in Fig. 15(D). At this time, the inclined surface 94 of the cam receiving surface 93 of the knock rotor 90 and the cam surface 73 of the outer cam 77 coincide with each other, and the vertical wall surface 95 of the first protrusion 71 of the outer cam 77 comes into contact with each other. 75The restriction on the rotation of the knock rotor 90 about the central axis thereof by the knock rotor 90 is released.

[0078] 15D, the knock member 80 and the knock rotor 90 move backward due to the biasing force of the biasing spring 99. At this time, the rotation of the knock rotor 90 around the central axis is caused by the vertical wall surface of the first protrusion 71 of the outer cam 77. 75 Therefore, when the sloping surface 94 of the cam receiving surface 93 of the knock rotor 90 presses against the cam surface 73 of the outer cam 77 or the sloping surface 86 of the cam surface 83 of the knock member 80 due to the urging force of the urging spring 99, the knock rotor 90 receives a circumferential component force and rotates about the central axis.

[0079] Since the knock rotor 90 moves backward while rotating, as shown in Fig. 15(E), the protrusions 92a of the inner cam 92 are disposed between the first protrusions 71 of the outer cam 77, and the first protrusions 71 of the outer cam 77 are disposed between the protrusions 92a of the inner cam 92, i.e., in the vertical grooves 91. As a result, the engagement between the outer cam 77 and the inner cam 92 is released. 75 15(E) , the knock member 80 and the knock rotor 90 move backward, and return to the state shown in FIG 15(A).

[0080] 16(B), the knock rotor 90 moves forward, so that the urging spring 99 is further compressed. One end of the urging spring 99 abuts against the knock rotor 90, and the other end of the urging spring 99 abuts against the rear end surface of the rotation drive mechanism 22. Therefore, the rotation drive mechanism 22 moves forward by a distance D compared to the state shown in FIG 16(A) due to the balance between the forward urging force increased by the compression of the urging spring 99 and the rearward urging force of the shaft spring 26.

[0081] When the rotation drive mechanism 22 advances, minute clearances existing between the various members inside the barrel 11, such as the tip member 14, the chuck unit 20, and the relay member 21, disappear. As a result, the rotor 30 moves backward relatively in the rotation drive mechanism 22, and the rotor 30 enters the state shown in Fig. 4(C), so that the rotation of the rotor 30 is locked.

[0082] In the third mechanical pencil 3, the user can perform two knock operations: a rotation lock knock operation that turns the rotation drive mechanism 22 on or off, and a feed knock operation that feeds out the writing lead. That is, when it is desired to turn the rotation drive mechanism 22 on or off, the knock member 80 and thus the knock rotor 90 are advanced until the inner cam 92 passes the outer cam 77 in the front-rear direction, as described with reference to FIG. 15. On the other hand, the knock operation for feeding out the writing lead advances the knock member 80 and thus the chuck unit 20 to an extent that the chuck unit 20 operates. That is, the rotation lock knock operation requires a deeper knock than the feed knock operation. The writing lead is also fed out in the rotation lock knock operation.

[0083] FIG. 17 is a vertical cross-sectional view for explaining the operation of the fourth rotation lock mechanism. The fourth rotation lock mechanism has a spacer 100 in addition to the configuration of the third rotation lock mechanism. The spacer 100 is disposed in front of the rotor 30. Specifically, it is disposed so as to fit into the outer peripheral surface of the relay member 21 at the rear end of the front shaft 12. When the knock rotor 90, and thus the rotation drive mechanism 22, advances due to the knock operation, the front end surface of the rotor 30 abuts against the rear end surface of the spacer 100, and the advancement of the rotor 30 is restricted. As a result, the rotor 30 is in the state shown in FIG. 4(C), and the rotation of the rotor 30 is locked.

[0084] Since the fourth rotation lock mechanism has the spacer 100 in addition to the third rotation lock mechanism, the spacer 100 directly presses the rotor 30, so that the rotation of the rotor 30 can be locked more reliably.

[0085] By the way, writing instruments equipped with a rotating mechanism that allows the refill to be inserted and removed by rotating a part of the barrel, i.e., the front or rear barrel, around the central axis are generally known. Next, a rotation lock mechanism that utilizes the novel rotating mechanism will be described. Before that, the structure of the ballpoint pen equipped with the novel rotating mechanism will be described.

[0086] 18 is a vertical cross-sectional view of the first ballpoint pen 5 in a non-writing state. The first ballpoint pen 5 has a cylindrical barrel 11. The barrel 11 has a front barrel 12, a rear barrel 110 that fits or screws into the rear end of the front barrel 12, and a cylindrical third rotating member 120 provided at the rear end of the rear barrel 110. The first ballpoint pen 5 also has a refill 7 that is a writing body that is disposed in the barrel 11 and has a writing part 6 at one end, a coil spring 8, a spring support member 9, and a first sliding member 130.

[0087] In the axial direction of the first ballpoint pen 5, the side of the writing part 6 is defined as the "front" side, and the side opposite the writing part 6 is defined as the "rear" side. In the first ballpoint pen 5, the refill 7 moves back and forth within the barrel 11 by operating the first rotating extension mechanism. At this time, the state in which the writing part 6 protrudes from the barrel 11 is called the writing state (Fig. 23), and the state in which the writing part 6 is retracted into the barrel 11 is called the non-writing state (Figs. 18 and 22).

[0088] FIG. 19 is a vertical cross-sectional view of the rear end of the rear barrel 110 of the first ballpoint pen 5. In FIG. 19, the upper side is the rear side of the first ballpoint pen 5. An annular protrusion 111 is provided along the circumferential direction on the inner peripheral surface of the rear part of the rear barrel 110. As shown in FIG. 24 described later, the annular protrusion 111 is not provided over the entire circumference. For example, in a portion along the circumferential direction on the inner peripheral surface of the rear barrel 110, for example, a quarter of the entire circumference, a recess 112 is defined instead of the annular protrusion 111. Two small protrusions 113 are provided in the recess 112, slightly spaced from both ends of the annular protrusion 111. As a result, two locking recesses 114 are defined between the annular protrusion 111 and the small protrusion 113. A key protrusion 115 is provided in the center of the annular protrusion 111 in the circumferential direction, and a similar key protrusion 115 is provided in the center of the recess 112 in the opposing circumferential direction. The two key protrusions 115 are provided adjacent to the annular protrusion 111 in the axial direction.

[0089] FIG. 20 is a perspective view of the third rotating member 120 of the first ballpoint pen 5. In FIG. 20, the upper side is the rear side of the first ballpoint pen 5. The third rotating member 120 is attached to the rear shaft 110 so as to be rotatable around the central axis. The third rotating member 120 has a cylindrical grip portion 121 that is gripped by the user when rotating the third rotating member 120. A clip 121a is provided on the outer peripheral surface of the grip portion 121. An insertion portion 122 that is formed with a smaller diameter and is inserted into the rear shaft 110 is provided in front of the grip portion 121. The insertion portion 122 is provided with two substantially rectangular cutout portions 123 that face each other from the front end surface toward the rear. The two cutout portions 123 define two cam arms 124 that extend toward the front. The front end surfaces of the two cam arms 124 are provided with cam surfaces 125 that are inclined in the same direction along the circumferential direction. A rectangular protrusion 126 extending forward is defined in the center of the front end face of the insertion portion 122 in one of the cutouts. A locking protrusion 127 is provided on the outer surface of the rectangular protrusion 126. A sliding groove 128 is provided along the circumferential direction on the outer surface of each of the two cam arms 124 at the same position as the locking protrusion 127 in the axial direction.

[0090] FIG. 21 is a perspective view of the first sliding member 130 of the first ballpoint pen 5. In FIG. 21, the upper side is the rear side of the first ballpoint pen 5. The first sliding member 130 has a sliding main body 131. The sliding main body 131 is a cylindrical member with a closed rear end. Two cam protrusions 132 are provided on the outer circumferential surface of the sliding main body 131. The two cam protrusions 132 are separated from each other by two key grooves 133 extending along the axial direction. The rear end surfaces of the two cam protrusions 132 are provided with cam receiving surfaces 134 that are inclined in the same manner as the cam surface 125 of the third rotating member 120. In each of the cam receiving surfaces 134, the portion located most forward is defined as a starting end 134a, and the portion located most rearward is defined as a terminal end 134b.

[0091] In the axle tube 11, the third rotating member 120 is inserted from the rear of the rear axle 110. At this time, the two cam arms 124 are bent radially inward, and the annular protrusion 111 of the rear axle 110 is disposed in the sliding groove 128. When the third rotating member 120 is rotated around the central axis relative to the rear axle 110, the sliding groove 128 serves as a rail, and the annular protrusion 111 can be moved relatively within the sliding groove 128. In addition, by disposing the annular protrusion 111 of the rear axle 110 in the sliding groove 128 of the third rotating member 120, the third rotating member 120 is less likely to come off the rear axle 110. The locking protrusion 127 of the third rotating member 120 is disposed in the recess 112.

[0092] The first sliding member 130 is inserted into the rear axle 110 from the front, and the rear end of the sliding body 131 is inserted into the third rotating member 120 from the front. When the first sliding member 130 is inserted, the cam arm 124 of the third rotating member 120 is guided by the cam receiving surface 134 of the first sliding member 130 so that the key protrusion 115 of the rear axle 110 is disposed in the key groove 133 of the first sliding member 130. By disposing the key protrusion 115 in the key groove 133, the first sliding member 130 can move back and forth within the axle tube 11 without rotating around the central axis. By inserting the sliding body 131 of the first sliding member 130 into the third rotating member 120, the two cam arms 124 cannot bend radially inward. As a result, it is possible to prevent the third rotating member 120 from falling off the rear axle 110.

[0093] The first sliding member 130 is biased rearward by a coil spring 8. One end of the coil spring 8 abuts against the front end surface of a cam protrusion 132 of the first sliding member 130, and the other end of the coil spring 8 is supported by a spring support member 9. The spring support member 9 is supported by the rear end surface of the front shaft 12. forward The refill 7 penetrates the coil spring 8 and the spring support member 9. The rear end of the refill 7 is inserted into the inside of the sliding main body portion 131 through an opening at the front thereof and fitted therein, whereby the refill 7 is attached integrally to the first sliding member 130 (FIG. 18).

[0094] Fig. 22 is a perspective view of the first ballpoint pen 5 in a non-writing state, and Fig. 23 is a perspective view of the first ballpoint pen 5 in a writing state. The rear barrel 110 is omitted in Figs. 22 and 23.

[0095] 22, the retraction of the first sliding member 130 by the coil spring 8 is regulated by the cam arm 124 engaging with the cam protrusion 132 in a state in which the cam arm 124 of the third rotating member 120 abuts against the key protrusion 115 of the rear shaft 110 in the circumferential direction to regulate the rotation of the third rotating member 120, as described below. At this time, the cam surface 125 of the third rotating member 120 is disposed at the starting end 134a of the cam receiving surface 134 of the first sliding member 130.

[0096] From this state, when the third rotating member 120 is rotated by gripping the gripping portion 121, the cam surface 125 of the third rotating member 120 and the cam receiving surface 134 of the first sliding member 130 cooperate with each other to convert the rotational force applied to the third rotating member 120 into a force that advances the first sliding member 130. That is, the cam surface 125 and the cam receiving surface 134 receive axial component forces from inclined surfaces that are inclined in the same direction, and the first sliding member 130 advances against the biasing force of the coil spring 8. When the cam surface 125 of the third rotating member 120 moves to the terminal end portion 134b on the cam receiving surface 134 of the first sliding member 130, the advancement of the first sliding member 130 stops, and the first ballpoint pen 5 enters a writing state (FIG. 23).

[0097] On the other hand, in the writing state shown in Fig. 23, by rotating the third rotating member 120 in the reverse direction, the first sliding member 130 retreats under the biasing force of the coil spring 8. When the cam surface 125 of the third rotating member 120 moves to the starting end 134a on the cam receiving surface 134 of the first sliding member 130, the retreat of the first sliding member 130 stops, and the first ballpoint pen 5 enters a non-writing state (Fig. 22).

[0098] Fig. 24 is a cross-sectional view explaining the operation of the first rotating feed mechanism. Specifically, Fig. 24 is a cross-sectional view including the locking protrusion 127 of the third rotating member 120 in the first ballpoint pen 5. Fig. 24(A) shows the first ballpoint pen 5 in a non-writing state corresponding to Fig. 22, in which the third rotating member 120 is rotated in one direction. On the other hand, Fig. 24(B) shows the first ballpoint pen 5 in a writing state corresponding to Fig. 23, in which the third rotating member 120 is rotated in the other direction.

[0099] As shown in FIG. 24(A), one of the cam arms 124 abuts against one of the key protrusions 115 in the circumferential direction. In contrast, as shown in FIG. 24(B), the one of the cam arms 124 abuts against the other of the key protrusions 115 in the circumferential direction. In each case, that is, when the cam arm 124 abuts against the key protrusions 115, the locking protrusions 127 of the third rotating member 120 are fitted into the locking recesses 114 of the rear shaft 110. In other words, the locking protrusions 127 ride over the small protrusions 113 in response to the rotation of the third rotating member 120, and at the same time that the cam arm 124 abuts against the key protrusions 115, the locking protrusions 127 are fitted into the locking recesses 114. As a result, the third rotating member 120 can be temporarily fixed, and the writing state or the non-writing state is prevented from being released unintentionally.

[0100] When the locking protrusion 127 passes over the small protrusion 113, the rectangular protrusion 126 bends radially inward, so that the locking protrusion 127 snaps into the locking recess 114. Therefore, the user receives feedback that the extension is complete as a clicking sound or clicking sensation. By changing the height of the small protrusion 113 or the locking protrusion 127, the degree of the clicking sound or clicking sensation can be freely designed.

[0101] In short, the above-mentioned first rotating payout mechanism comprises an axle tube 11 having an internal locking portion, a third rotating member 120 rotatably arranged around the central axis relative to the rear axle 110, and a first sliding member 130 which cooperates with the third rotating member 120. Each of the third rotating member 120 and the first sliding member 130 has a cam surface which cooperates with the other of the third rotating member 120 and the first sliding member 130. Depending on the rotation direction of the third rotating member 120, the first sliding member 130 moves back and forth within the axle tube 11. When the third rotating member 120 is rotated in one direction, the first sliding member 130 moves forward and backward until the third rotating member 120 locks with the locking portion, and when the third rotating member 120 is rotated in the other direction, the first sliding member 130 moves backward until the third rotating member 120 locks with the locking portion.

[0102] Here, the locking portion has a first locking portion that locks the rotation of the third rotating member 120 in the forward direction, and a second locking portion that locks the rotation of the third rotating member 120 in the reverse direction. The first locking portion is specifically the key protrusion portion 115, and the second locking portion is specifically the locking recess portion 114. The "forward direction" refers to the direction in which the user intends to rotate, and the "reverse direction" refers to the direction opposite to the direction in which the user intends to rotate. In addition, the third rotating member 120 has a first locked portion that locks with the first locking portion, and a second locked portion that locks with the second locking portion. The first locked portion is specifically the cam arm 124, and the second locked portion is specifically the locking protrusion portion 127.

[0103] The cam surface 125 of the third rotating member 120 and the cam receiving surface 134 of the first sliding member 130 may be configured in any manner as long as the rotational motion of the third rotating member 120 can be converted into the linear motion of the first sliding member 130. Therefore, at least one of the third rotating member 120 and the first sliding member 130 may be formed with a cam surface that cooperates with the other of the third rotating member 120 and the first sliding member 130. In addition, the number of the cam arms 124 of the third rotating member 120 and the corresponding cam protrusions 132 of the first sliding member 130 may each be at least one, may be three or more, or may be different from each other.

[0104] According to the above-mentioned first rotating delivery mechanism, as described above, when the third rotating member 120 is rotated in one direction, the first sliding member 130 advances until the third rotating member 120 engages with the locking portion, and when the third rotating member 120 is rotated in the other direction, the first sliding member 130 retreats until the third rotating member 120 engages with the locking portion. Therefore, delivery can be performed reliably with an efficient operation and structure. In addition, since the third rotating member 120 has a first locking portion that locks the third rotating member 120 against rotation in the forward direction and a second locking portion that locks the third rotating member 120 against rotation in the reverse direction, the intended rotation is stopped and reverse rotation is also prevented, thereby enabling more reliable delivery.

[0105] In addition, the cam surface, which is a mechanism for converting rotational motion into linear motion, i.e., the cam surface 125 of the third rotating member 120 and the cam receiving surface 134 of the first sliding member 130, and the locking portion, which is a mechanism for locking rotation, i.e., the locking recess 114, the key protrusion 115, the cam arm 124, and the locking protrusion 127, are arranged at a distance, specifically, in the axial direction. Therefore, since separate mechanisms for converting motion and locking rotation can be designed and arranged independently, the above-mentioned first rotating / propelling mechanism allows for more flexible design. For example, by changing the angle of inclination of the cam surface 125 of the third rotating member 120 and the cam receiving surface 134 of the first sliding member 130, the linear amount relative to the rotation amount can be easily adjusted. In addition, the above-mentioned first rotating / propelling mechanism allows for a rotating / propelling mechanism to be realized with fewer parts than the conventional rotating / propelling mechanism, and the parts can be easily molded or processed.

[0106] Since the rotation of the third rotating member 120 is restricted by the side surface of the cam arm 124 abutting against the side surface of the key protrusion 115 of the rear axle 110, even if an excessive force is applied to rotate the third rotating member 120, the rotation can be reliably restricted. Furthermore, since the mechanism for restricting such rotation is separated from the conversion mechanism that converts rotational motion into linear motion and the locking mechanism that locks the rotation, the conversion mechanism and the locking mechanism will not be damaged by excessive force.

[0107] The above-mentioned first rotating mechanism can be widely applied to all applicators. That is, the applicator includes the above-mentioned first rotating mechanism and an applicator body, and the applicator body moves back and forth together with the sliding member. Here, the term "applicator" broadly includes not only applicators for correction fluid, adhesives, and medicines, and applicators for cosmetics such as mascara, eyeliner, lipstick, and nail polish, but also writing instruments such as ballpoint pens, felt-tip pens, marker pens, mechanical pencils, fountain pens, and thermochromic writing instruments. In addition, the term "applicator body" broadly includes writing instruments such as ballpoint pen refills and ink containers for eyeliners, depending on the above-mentioned applicator.

[0108] The refill as the writing body in the thermochromic writing instrument may contain thermochromic ink. In this case, the handwriting can be thermochromic due to frictional heat generated when rubbed by a friction body as an erasing member. Here, the thermochromic ink refers to an ink that has the property of maintaining a predetermined color (first color) at room temperature (e.g., 25°C), changing to another color (second color) when heated to a predetermined temperature (e.g., 60°C), and then returning to the original color (first color) when cooled to a predetermined temperature (e.g., -5°C). In a thermochromic writing instrument using thermochromic ink, the second color is made colorless, and the drawn lines written in the first color (e.g., red) are heated to make them colorless, which is referred to as "erasing" here. Therefore, the friction body as the erasing part rubs against the writing surface on which the drawn lines have been written to generate frictional heat, thereby changing the drawn lines to colorless, that is, erasing them. Needless to say, the second color may be a color other than colorless.

[0109] Next, a rotation lock mechanism using the above-mentioned rotation advance mechanism will be described. FIG. 25 is a vertical cross-sectional view of the fourth mechanical pencil 4. Compared to the first mechanical pencil 1, the fourth mechanical pencil 4 has a fifth rotation lock mechanism instead of the first rotation lock mechanism, and has a second rotation advance mechanism instead of the first rotation advance mechanism. The fifth rotation lock mechanism has a fourth rotation member 150, a second sliding member 160, and a biasing spring 169, and uses the above-mentioned rotation advance mechanism. Other rotation advance mechanisms may be applied to configure the fifth rotation lock mechanism. The second rotation advance mechanism of the fourth mechanical pencil 4 is significantly different from the first rotation advance mechanism of the first ballpoint pen 5 only in the length of the sliding member.

[0110] FIG. 26 is a vertical cross-sectional view of the rear end of the rear shaft 140 of the fourth mechanical pencil 4. In FIG. 26, the upper side is the rear side of the fourth mechanical pencil 4. An annular protrusion 141 is provided along the circumferential direction on the inner peripheral surface of the rear part of the rear shaft 140. As shown in FIG. 29 described later, the annular protrusion 141 is not provided over the entire circumference. For example, on the inner peripheral surface of the rear shaft 140, in a portion along the circumferential direction, for example, a quarter of the entire circumference, a recess 142 is defined instead of the annular protrusion 141. Two small protrusions 143 are provided in the recess 142, slightly spaced from both ends of the annular protrusion 141. As a result, two locking recesses 144 are defined between the annular protrusion 141 and the small protrusion 143. A key protrusion 145 is provided at the center of the annular protrusion 141 in the circumferential direction, and a similar key protrusion 145 is provided at the center of the opposing recess 142 in the circumferential direction. The two key protrusions 145 are provided adjacent to the annular protrusion 141 in the axial direction.

[0111] FIG. 27 is a perspective view of the fourth rotating member 150 of the fourth mechanical pencil 4. In FIG. 27, the upper side is the rear side of the fourth mechanical pencil 4. The fourth rotating member 150 is attached to the rear shaft 140 so as to be rotatable around the central axis. The fourth rotating member 150 has a cylindrical gripping portion 151 that is gripped by the user when rotating the fourth rotating member 150. A clip 151a is provided on the outer peripheral surface of the gripping portion 151. An insertion portion 152 that is formed with a smaller diameter and is inserted into the rear shaft 140 is provided in front of the gripping portion 151. The insertion portion 152 is provided with two substantially rectangular cutout portions 153 that face each other from the front end surface toward the rear. The two cutout portions 153 define two cam arms 154 that extend toward the front. The front end surfaces of the two cam arms 154 are provided with cam surfaces 125 that are inclined in the same direction along the circumferential direction. A rectangular protrusion 156 extending forward is defined in the center of the front end face of the insertion portion 152 in one of the cutouts. A locking protrusion 157 is provided on the outer surface of the rectangular protrusion 156. A sliding groove 158 is provided along the circumferential direction on the outer surface of each of the two cam arms 154 at the same position as the locking protrusion 157 in the axial direction.

[0112] FIG. 28 is a perspective view of the second sliding member 160 of the fourth mechanical pencil 4. In FIG. 28, the upper side is the rear side of the fourth mechanical pencil 4. The second sliding member 160 has a sliding main body 161. Two cam protrusions 162 are provided on the outer peripheral surface of the sliding main body 161. The two cam protrusions 162 are separated from each other by two key grooves 163 extending along the axial direction. The rear end surfaces of the two cam protrusions 162 are provided with cam receiving surfaces 164 that are inclined in the same manner as the cam surface 155 of the fourth rotating member 150. In each of the cam receiving surfaces 164, the portion located most forward is defined as a starting end 164a, and the portion located most rearward is defined as a terminal end 164b. The second sliding member 160 is provided with a through hole 165 along the central axis, and the lead case 23 is inserted into the through hole 165.

[0113] In the axle tube 11, the fourth rotating member 150 is inserted from the rear of the rear axle 140. At this time, the two cam arms 154 are bent radially inward, and the annular protrusion 141 of the rear axle 140 is disposed in the sliding groove 158. When the fourth rotating member 150 is rotated around the central axis relative to the rear axle 140, the sliding groove 158 serves as a rail, and the annular protrusion 141 can be moved relatively within the sliding groove 158. In addition, by disposing the annular protrusion 141 of the rear axle 140 in the sliding groove 158 of the fourth rotating member 150, the fourth rotating member 150 is less likely to come off the rear axle 140. The locking protrusion 157 of the fourth rotating member 150 is disposed in the recess 142.

[0114] The second sliding member 160 is inserted into the rear axle 140 from the front, and the rear end of the sliding body 161 is inserted into the fourth rotating member 150 from the front. When the second sliding member 160 is inserted, the cam arm 154 of the fourth rotating member 150 is guided by the cam receiving surface 164 of the second sliding member 160 so that the key protrusion 145 of the rear axle 140 is disposed in the key groove 163 of the second sliding member 160. By disposing the key protrusion 145 in the key groove 163, the second sliding member 160 can move back and forth within the axle tube 11 without rotating around the central axis. By inserting the sliding body 131 of the second sliding member 160 into the fourth rotating member 150, the two cam arms 154 cannot bend radially inward. As a result, it is possible to prevent the fourth rotating member 150 from falling off the rear axle 140.

[0115] The second sliding member 160 is biased rearward by a biasing spring 169. One end of the biasing spring 169 abuts against a step provided inside the second sliding member 160, and the other end of the biasing spring 169 is supported by the rear end surface of the rotation drive mechanism 22. The backward movement of the rotation drive mechanism 22 due to the biasing force of the shaft spring 26 is regulated by the rear end surface of the rotation drive mechanism 22 abutting against the front end surface 146 of the key protrusion of the rear axle 140.

[0116] Fig. 29 is a cross-sectional view for explaining the operation of the second rotation-advancing mechanism, and Fig. 30 is a vertical cross-sectional view for explaining the operation of the fifth rotation lock mechanism and the second rotation-advancing mechanism. Specifically, Fig. 29 is a cross-sectional view including the locking protrusion 157 of the fourth rotating member 150 in the fourth mechanical pencil 4. The states shown in Fig. 29(A) and Fig. 30(A) are a rotation unlocked state in which the rotation drive mechanism 22 is on, and the states shown in Fig. 29(B) and Fig. 30(B) are a rotation locked state in which the rotation drive mechanism 22 is off.

[0117] 29(A) and 30(A), in the rotation lock release state shown in FIG. 29(A) and FIG. 30(A), the retraction of the second sliding member 160 by the biasing spring 169 is restricted by the cam arm 154 of the fourth rotating member 150 engaging with the cam protrusion 162 in a state in which the cam arm 154 of the fourth rotating member 150 abuts against the key protrusion 145 of the rear axle 140 in the circumferential direction to restrict the rotation of the fourth rotating member 150, as described below. At this time, the cam surface 155 of the fourth rotating member 150 is disposed at the starting end 164a of the cam receiving surface 164 of the second sliding member 160.

[0118] From this state, when the fourth rotating member 150 is rotated by gripping the gripping portion 151, the cam surface 155 of the fourth rotating member 150 and the cam receiving surface 164 of the second sliding member 160 cooperate with each other, so that the force in the rotational direction applied to the fourth rotating member 150 is converted into a force that advances the second sliding member 160. That is, the cam surface 155 and the cam receiving surface 164 receive axial component forces from inclined surfaces that are inclined in the same direction, and the second sliding member 160 advances against the biasing force of the biasing spring 169. When the cam surface 155 of the fourth rotating member 150 moves to the terminal end portion 164b on the cam receiving surface 164 of the second sliding member 160, the advancement of the second sliding member 160 stops, and the rotation drive mechanism 22 enters a rotation locked state (FIGS. 29(B) and 30(B)).

[0119] In the rotation locked state, the second sliding member 160 is advanced, so that the biasing spring 169 is further compressed. One end of the biasing spring 169 abuts against the second sliding member 160, and the other end of the biasing spring 169 abuts against the rear end surface of the rotation drive mechanism 22. Therefore, the rotation drive mechanism 22 advances by a distance D compared to the state shown in Fig. 30(A) due to the balance between the forward biasing force increased by the compression of the biasing spring 169 and the rearward biasing force of the shaft spring 26.

[0120] When the rotation drive mechanism 22 advances, minute clearances existing between the various members inside the barrel 11, such as the tip member 14, the chuck unit 20, and the relay member 21, disappear. As a result, the rotor 30 moves backward relatively in the rotation drive mechanism 22, and the rotor 30 enters the state shown in Fig. 4(C), so that the rotation of the rotor 30 is locked.

[0121] On the other hand, in the rotation locked state, by rotating the fourth rotating member 150 in the reverse direction, the second sliding member 160 retreats under the biasing force of the biasing spring 169. When the cam surface 155 of the fourth rotating member 150 moves to the starting end 164a on the cam receiving surface 164 of the second sliding member 160, the retreat of the second sliding member 160 stops, and the rotation drive mechanism 22 enters the rotation unlocked state (FIGS. 29(A) and 30(A)).

[0122] The rotation of the fourth rotating member 150 is restricted by the side surface of the cam arm 154 abutting against the side surface of the key projection 145 of the rear axle 140. That is, as shown in FIG. 29(A), one side of the cam arm 154 abuts against one side of the key projection 145 in the circumferential direction. In contrast, as shown in FIG. 29(B), the one side of the cam arm 154 abuts against the other side of the key projection 145 in the circumferential direction. In each case, that is, when the cam arm 154 abuts against the key projection 145, the locking projection 157 of the fourth rotating member 150 fits into the locking recess 144 of the rear axle 140. In short, the locking projection 157 rides over the small projection 143 in response to the rotation of the fourth rotating member 150, and fits into the locking recess 144 at the same time as the cam arm 154 abuts against the key projection 145. As a result, the fourth rotating member 150 can be temporarily fixed, and the rotation locked state or the rotation unlocked state can be prevented from being unintentionally released.

[0123] When the locking protrusion 157 passes over the small protrusion 143, the rectangular protrusion 156 bends radially inward, so that the locking protrusion 157 snaps into the locking recess 144. Therefore, the user receives feedback that the extension is complete as a clicking sound or clicking sensation. By changing the height of the small protrusion 143 or the locking protrusion 157, the degree of the clicking sound or clicking sensation can be freely designed.

[0124] The second rotation mechanism that moves the second sliding member 160 forward or backward by the rotation of the fourth rotation member 150 and the retraction mechanism that advances the writing lead by a knock operation that presses the knock member 24 or the knock cover 15 forward can be operated independently. Therefore, in the fourth mechanical pencil 4, the knock operation can be performed even if the rotation drive mechanism is turned on or off by the fifth rotation lock mechanism.

[0125] FIG. 31 is a vertical cross-sectional view for explaining the operation of the sixth rotation lock mechanism. The sixth rotation lock mechanism has a spacer 100 in addition to the configuration of the fifth rotation lock mechanism. The spacer 100 is disposed in front of the rotor 30. Specifically, the spacer 100 is disposed so as to fit into the outer peripheral surface of the relay member 21 at the rear end of the front shaft 12. When the second sliding member 160, and thus the rotation drive mechanism 22, advances by the operation of the second rotation feed mechanism, the front end surface of the rotor 30 abuts against the rear end surface of the spacer 100, and the advancement of the rotor 30 is restricted. As a result, the rotor 30 is in the state shown in FIG. 4(C), and the rotation of the rotor 30 is locked.

[0126] Since the sixth rotation lock mechanism has the spacer 100 in addition to the fifth rotation lock mechanism, the spacer 100 directly presses the rotor 30, so that the rotation of the rotor 30 can be locked more reliably.

[0127] The rotation lock mechanism may be configured as desired so long as it is configured to lock the rotor in a relatively retreated state in the rotation drive mechanism. The rotation lock mechanism may be configured to press the rotor backward or press the rotation drive mechanism forward to cause the rotor to retreat relatively in the rotation drive mechanism. The rotor or the rotation drive mechanism may be pressed directly or indirectly by the rotation lock mechanism. The rotation lock mechanism may have a rotating member equipped with a cam, and the rotational motion of the rotating member may be converted into linear motion by the action of the cam to press the rotor.

[0128] Naturally, even when the rotation lock mechanism has locked the rotor, the writing lead can be advanced by moving the chuck unit 20 back and forth. That is, when the rotation lock mechanism has locked the rotor, the chuck unit 20 does not affect the forward or backward movement of the chuck unit 20 by the knock operation. Therefore, the mechanical pencil with the rotor locked by the rotation lock mechanism can be used in the same way as a normal mechanical pencil. Therefore, for example, when writing shorthand, if the forward and backward movement of the writing lead by the rotation drive mechanism is bothersome, the rotation drive mechanism can be turned off. On the other hand, when writing carefully to prevent unevenness in the thickness of handwriting due to uneven wear of the writing lead, the rotation drive mechanism can be turned on. In short, the user can freely switch the rotation drive mechanism between on (operating or enabled) and off (stopped or disabled).

[0129] According to the second rotation lock mechanism, the rotor is pressed backward via the chuck unit, but the lead case may be pushed backward from the front or pulled from the rear to move the lead case back. By moving the lead case back, the relay member 21 moves back, which moves the rotor back and places the rotation drive mechanism 22 in a rotation lock state.

[0130] The rotation lock mechanism may have a retractable mechanism or a rotational extension mechanism that presses the rotational drive mechanism forward. The retractable mechanism or the rotational extension mechanism may have a spring and a sliding member that biases the spring, and the sliding member is advanced to press the rotational drive mechanism forward. The retractable mechanism may further have a knock member and a knock rotor that are arranged at the rear end of the barrel, and when a knock operation of the knock member is performed to advance the knock rotor to a predetermined position, the knock rotor rotates about the central axis, and the backward movement of the knock rotor is locked, and the rotational drive mechanism is advanced to lock the rotor in a relatively backward state in the rotational drive mechanism. [Explanation of symbols]

[0131] 1. No. 1 Mechanical Pencil 5. First ballpoint pen 8 Coil spring 11 Shaft tube 12 Front axle 14 Tip member 15 Knock Cover 16 Tip pipe 17 Eraser 18 Slider 19 Holding chuck 20 Chuck unit 21 Intermediate parts 22 Rotational drive mechanism 23 Lead Case 24 Knock parts 25 coil spring 26 Axle Spring 30 Rotor 31 Upper cam forming member 32 Lower cam forming member 33 Cylinder parts 34 Torque canceller 35 Cushion spring 40 rear axle 41 Regulatory protrusion 42 Front end surface 43 Through hole 44 Inclined cam receiving surface 50 Changeover Switch 51 Switch support part 52 Switch section 54 First rotating member 55 Cam body 56 Aperture 57 Support plate 58 Gap 59 Inclined cam surface 110 rear axle 120 Third rotating member 121 Gripping part 122 Insertion part 123 Cutout 124 Cam arm 125 Cam surface 130 First sliding member 131 Sliding body 132 Cam protrusion 133 Keyway 134 Cam receiving surface

Claims

1. A mechanical pencil is configured to release and grip a writing lead by the forward and backward movement of a chuck unit disposed in a barrel, thereby advancing the writing lead forward, and the chuck unit is held in the barrel so as to be rotatable about a central axis while gripping the writing lead, A mechanical pencil having a rotor, the rotor being retracted in response to a retracting movement of the chuck unit due to a writing pressure applied to the writing lead, and a rotation drive mechanism for rotating the rotor, the rotational movement of the rotor being transmitted to the writing lead via the chuck unit, Further comprising a rotation lock mechanism for locking the rotation of the rotor, The mechanical pencil is characterized in that the rotation lock mechanism is configured to lock the rotor in a relatively retreated state in the rotation drive mechanism.

2. 2. The mechanical pencil according to claim 1, wherein the rotation lock mechanism is configured to push the rotor backward or push the rotation drive mechanism forward to cause the rotor to move backward relatively in the rotation drive mechanism.

3. The mechanical pencil according to claim 2 , wherein the rotor or the rotation drive mechanism is pressed directly or indirectly by the rotation lock mechanism.

4. 4. The mechanical pencil according to claim 3, wherein the rotation lock mechanism has a rotating member equipped with a cam, and the rotational motion of the rotating member is converted into linear motion by the action of the cam to press the rotor.

5. The mechanical pencil according to claim 4, wherein the rotor is pressed backward through the chuck unit.

6. 6. The mechanical pencil according to claim 4, wherein the rotation lock mechanism has a retractable mechanism or a rotary extension mechanism that presses the rotary drive mechanism forward.

7. 7. The mechanical pencil according to claim 6, wherein the extension / retraction mechanism or the rotary extension mechanism has a spring and a sliding member that biases the spring, and the sliding member is advanced to press the rotary drive mechanism forward.

8. The retractable mechanism further includes a knock member and a knock rotor disposed at a rear end of the barrel, 8. The mechanical pencil according to claim 6, wherein when a knock operation of the knock member is performed to advance the knock rotor to a predetermined position, the knock rotor rotates about a central axis, and the backward movement of the knock rotor is locked, and the rotation drive mechanism is advanced so that the rotor is locked in a relatively backward state in the rotation drive mechanism.

9. 9. The mechanical pencil according to claim 6, wherein the rotor is pressed backward via a spacer.

10. The mechanical pencil according to claim 1 , wherein the writing lead is advanced by moving the chuck unit back and forth while the rotation lock mechanism locks the rotor.

11. the rotation drive mechanism has a first cam forming member and a second cam forming member, the rotor is formed in an annular shape, a first cam surface and a second cam surface are formed on one end surface and the other end surface in the axial direction, respectively, and a first fixed cam surface and a second fixed cam surface are formed on the first cam forming member and the second cam forming member so as to face the first cam surface and the second cam surface, respectively; a retraction movement of the chuck unit due to the writing pressure causes the first cam surface of the rotor to come into contact with and mesh with the first fixed cam surface, and a release of the writing pressure causes the second cam surface of the rotor to come into contact with and mesh with the second fixed cam surface, When the first cam surface of the rotor is engaged with the first fixed cam surface, the second cam surface of the rotor and the second fixed cam surface are set in a phase-shifted relationship with respect to one tooth of a cam in the axial direction, and when the second cam surface of the rotor is engaged with the second fixed cam surface, the first cam surface of the rotor and the first fixed cam surface are set in a phase-shifted relationship with respect to one tooth of a cam in the axial direction, The mechanical pencil according to claim 1 , wherein the rotation drive mechanism locks the rotor by meshing the first cam surface of the rotor with the first fixed cam surface.

Images