CN113286712A

CN113286712A - Ink inhaler

Info

Publication number: CN113286712A
Application number: CN201980085515.7A
Authority: CN
Inventors: 芳野清隆
Original assignee: Pilot Corp
Current assignee: Pilot Corp
Priority date: 2018-12-26
Filing date: 2019-12-25
Publication date: 2021-08-20
Anticipated expiration: 2039-12-25
Also published as: JP7246410B2; WO2020138227A1; JPWO2020138227A1; TW202031520A; CN113286712B; TWI794572B

Abstract

Provided is an ink inhaler which can promote air flow into an ink containing part and make ink flow out smoothly. An ink inhaler (20) is provided with: a main tube (30) having a reduced diameter portion (31) on an inner surface (30a), and defining an ink storage portion (21) behind the reduced diameter portion (31); a piston member (50) that is disposed so as to be movable forward and backward with respect to the main cylinder (30); a tube (70) that extends within the main cylinder (30) through the inside of the reduced diameter portion (31) and is held so as to be movable forward and backward with respect to the piston member (50); and a fixed block member (80) fixed to the pipe (70) at the rear of the reduced diameter portion (31), wherein the inner surface (30a) of the main tube (30) in front of the reduced diameter portion (31) has a front inclined surface (31b) inclined with respect to the axial direction and the radial direction, or has a front rib (34) extending in a plane including the central axis (A) of the main tube (30).

Description

Ink inhaler

Technical Field

The present invention relates to an ink inhaler for a writing instrument such as a pen.

Background

Conventionally, in writing instruments such as pens, ink inhalers have been used which suck ink therein, store the ink therein, and supply the ink to a pen tip during writing. The ink inhaler has an ink containing portion and an ink suction mechanism for sucking ink into the ink containing portion.

The ink inhalation mechanism generally has a mechanism for generating a negative pressure in the ink inhaler to inhale ink by utilizing a difference in air pressure between the inside and the outside of the ink inhaler. Examples of the method of generating negative pressure in the ink inhaler include the following methods: a slide type in which a piston member connected to a front side of an operation member is moved rearward by linearly operating the operation member rearward, thereby generating a negative pressure in an ink inhaler; a rotary type in which an operating member is rotated about an axis to move a piston member screwed to the operating member rearward, thereby generating a negative pressure in the ink inhaler; and a push type that generates negative pressure in the ink inhaler by pushing forward a piston member provided at the rear of the ink inhaler and then releasing the piston member. In particular, in the push-type ink inhaler, the length of the operation member can be reduced as compared with a slide-type or rotary-type ink inhaler. This makes it possible to reduce the size of the ink inhaler having the same capacity or to increase the capacity of the ink inhaler having the same size.

JP2017-209863a discloses an ink suction device including: an ink cartridge having a reduced diameter portion (inner section) and an ink accommodating chamber; a piston member disposed at a rear portion of the ink cartridge; a tube which is disposed in the ink cartridge and is held by the piston member; and a block fixed to the tube.

In a conventional push-type ink inhaler, ink may not flow smoothly from an ink containing portion (ink containing chamber) to a pen tip. The present inventors have conducted intensive studies on the above-mentioned cause, and as a result, have found that the following problems are present in the conventional push-type ink inhaler.

When the ink advances through the reduced diameter portion and reaches the pen tip, air flows into the ink containing portion through the reduced diameter portion instead of the ink flowing out of the ink containing portion. However, in this case, air may not properly flow into the ink containing portion, and the ink may be prevented from smoothly flowing out of the ink containing portion. Further, as a result of further investigation on this problem, it has been found that air heading into the ink containing portion is trapped in front of the reduced diameter portion, thereby preventing the air from flowing into the ink containing portion.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide an ink inhaler capable of promoting the inflow of air into an ink containing portion and smoothly discharging ink.

An ink inhaler of the present invention includes: a main cylinder having a reduced diameter portion on an inner surface thereof, the main cylinder defining an ink accommodating portion behind the reduced diameter portion; a piston member disposed to be movable forward and backward with respect to the main cylinder; a tube that extends inside the main cylinder through the inside of the reduced diameter portion and is held so as to be movable forward and backward with respect to the piston member; and a fixed block member fixed to the pipe at a rear portion of the reduced diameter portion, wherein the main cylinder has a front inclined surface inclined with respect to an axial direction and a radial direction on an inner surface in front of the reduced diameter portion, or a front rib extending in a plane including a central axis of the main cylinder.

In the ink inhaler of the present invention, the main cylinder may have the front inclined surface, and the front inclined surface may have a groove portion extending in a plane including a central axis of the main cylinder.

In the ink inhaler of the present invention, the main cylinder may have a plurality of the groove portions arranged in a circumferential direction.

In the ink inhaler of the present invention, the circumferential width of the groove may be reduced toward the front.

In the ink inhaler of the present invention, the main cylinder may have the front rib, and the front rib may have a corner facing the central axis in a cross section perpendicular to the central axis.

In the ink inhaler of the present invention, the main cylinder may have the front rib, and the front rib may include a portion in which a distance from the central axis in a radial direction decreases with increasing distance to the rear side in a front parallel portion of the inner surface that is parallel to the central axis.

In the ink inhaler of the present invention, the main cylinder may have a plurality of the front ribs arranged in a circumferential direction.

In the ink inhaler of the present invention, the interval between two of the front ribs adjacent in the circumferential direction may be 2.7mm or more.

In the ink inhaler of the present invention, the main cylinder may have a rear rib extending in a plane including a central axis of the main cylinder on an inner surface of the ink containing portion.

In the ink inhaler of the present invention, the main cylinder may have a plurality of rear ribs arranged in a circumferential direction.

In the ink inhaler of the present invention, the interval between two of the rear ribs adjacent in the circumferential direction may be 2.7mm or more.

Effects of the invention

According to the present invention, it is possible to provide an ink inhaler capable of promoting air flow into an ink containing portion and smoothly discharging ink.

Drawings

Fig. 1 is a diagram for explaining an embodiment of the present invention, and is a diagram showing a cross section of a writing instrument incorporating an ink inhaler.

Fig. 2 is a cross-sectional view showing the ink inhaler in an enlarged manner, particularly, in a released state.

Fig. 3 is a sectional view showing the ink inhaler in a state where an operation member of the ink inhaler is pressed forward.

Fig. 4 is a diagram showing the ink inhaler in a state where the pen tip is disposed upward.

Fig. 5 is a sectional view showing the ink inhaler in a state where the central axis is inclined with respect to the vertical direction.

Fig. 6 is a view showing a section corresponding to the VI-VI line of fig. 5.

Fig. 7A is a view showing an example of a cross section corresponding to line VII-VII of fig. 5.

Fig. 7B is a view showing another example of a cross section corresponding to line VII-VII in fig. 5.

Fig. 8 is a sectional view showing a modification of the ink inhaler.

Fig. 9 is a sectional view corresponding to line IX-IX of fig. 8.

Fig. 10 is a sectional view corresponding to the X-X line of fig. 8.

Detailed Description

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings of the present specification, the scale, the aspect ratio, and the like are exaggerated for convenience of illustration and understanding, and are appropriately changed depending on the actual situation.

The terms such as "parallel", "perpendicular" and "the same" and the values of the length and the angle are not strictly limited, and are to be construed as including ranges to the extent that the same function can be expected.

Fig. 1 to 10 are diagrams for explaining an embodiment of the present invention. Fig. 1 is a cross-sectional view showing a writing instrument 10 in which an ink inhaler 20 is incorporated, fig. 2 is an enlarged view showing the ink inhaler 20, and fig. 3 is a cross-sectional view showing the ink inhaler 20 in a state in which an operating member 60 of the ink inhaler 20 is pressed forward. In the present embodiment, an example in which the writing instrument 10 is a pen is described, but the writing instrument 10 is not limited to a pen. In the present specification, a direction (longitudinal direction) in which the central axis a of the main cylinder 30 of the ink inhaler 20 extends is defined as an axial direction, a direction perpendicular to the central axis a is defined as a radial direction, and a circumferential direction around the central axis a is defined as a circumferential direction. In the writing instrument 10 and the ink inhaler 20, a side close to a surface to be written such as a paper surface (for example, a lower side in fig. 1) in the axial direction during writing is defined as a front side, and a side far from the surface to be written (for example, an upper side in fig. 1) is defined as a rear side.

The writing instrument 10 shown in fig. 1 includes a barrel 11, a pen tip 12, and a pen tip support portion 13 which is positioned in front of the barrel 11 and supports the pen tip 12. The shaft tube 11 is a member having a longitudinal direction along the central axis a, and has a hollow inside that opens forward. In the present embodiment, at least a part of the ink inhaler 20 is housed in the hollow of the barrel 11. The pen tip 12 is a member for forming handwriting on a surface to be written with ink supplied from the ink inhaler 20. The pen tip supporting portion 13 has an ink flow hole 14 and an air flow hole 15 therein. The ink circulation hole 14 communicates with the pen tip 12, and functions as a passage for guiding ink supplied from the ink suction device 20 to the pen tip 12. The air flow hole 15 extends substantially in the axial direction and opens in the vicinity of the pen tip 12. The air flow hole 15 functions as a passage for guiding the outside air flowing from the opening toward the ink inhaler 20. The pen tip supporting portion 13 is formed with a mounting portion 16 to which the ink supply water inhaler 20 is mounted. In the present embodiment, the mounting portion 16 is configured as a projecting portion that faces rearward, and the ink inhaler 20 is detachably mounted to the pen point support portion 13 by fitting the distal end portion of the ink inhaler 20 to the mounting portion 16. Further, the mounting portion 16 is not limited to this, and the ink inhaler 20 may be mounted to the pen tip supporting portion 13 by forming a groove portion that opens rearward, and pressing the front end portion of the ink inhaler 20 into the mounting portion 16. The outer surface of the rear portion of the pen tip supporting portion 13 is formed with an external thread portion, and the inner surface of the front portion of the barrel 11 is formed with an internal thread portion corresponding to the external thread portion. The shaft 11 is attached to the pen tip supporting portion 13 by screwing the female screw portion of the shaft 11 to the male screw portion of the pen tip supporting portion 13.

The ink inhaler 20 of the present embodiment is a push-type ink inhaler, and includes an ink storage unit 21 for storing ink to be supplied to the pen tip 12. The ink inhaler 20 includes: a main tube 30 defining an ink containing portion 21; a piston member 50 disposed to be movable forward and backward with respect to the main cylinder 30; a tube 70 held to be movable forward and backward with respect to the piston member 50; and a fixing block member 80 fixed to the tube 70. In the illustrated example, the ink inhaler 20 further includes: a tail cylinder 40 mounted to the rear of the main cylinder 30; an operating member 60 attached to the rear portion of the piston member 50; and a movable block member 90 which is clearance-fitted to the tube 70 at the rear of the fixed block member 80. Hereinafter, the respective components constituting the ink inhaler 20 of the present embodiment will be described in order.

The main tube 30 is a member having a substantially cylindrical shape, and has an inner surface 30a and an outer surface 30b extending in the axial direction. The inner surface 30a has a reduced diameter portion 31 with a reduced inner diameter. The reduced diameter portion 31 is a projection formed annularly in the circumferential direction on the inner surface 30 a. In particular, the reduced diameter portion 31 is a protruding portion formed by the inner surface 30a protruding toward the central axis a. The ink accommodating portion 21 is formed behind the reduced diameter portion 31. A rear inclined surface 31a is formed at a position rearward of a top portion of the diameter-reduced portion 31 closest to the central axis a, the rear inclined surface 31a faces the ink containing portion 21 and is inclined with respect to the axial direction and the radial direction, and a front inclined surface 31b is formed at a position forward of the top portion and is inclined with respect to the axial direction and the radial direction. The rear inclined surface 31a is a surface extending radially outward as it goes rearward, and the front inclined surface 31b is a surface extending radially outward as it goes forward.

The outer surface 30b of the main cylinder 30 is provided with a concave-convex portion 36. For example, the concave-convex portion 36 includes a convex portion and/or a concave portion extending in the circumferential direction. When the ink inhaler 20 is attached to and detached from the mounting portion 16 of the pen tip holder 13, the uneven portion 36 functions as a slip-proof member. That is, the user can easily and stably attach and detach the pen tip supporting portion 13 by gripping the concave-convex portion 36.

The rear portion of the main tube 30 is mounted with a tail tube 40. The tail cylinder 40 houses at least a part of the operation member 60. The rear end opening 42 of the tail tube 40 is formed with a brim 44 projecting inward, and in the released state of the operation member 60, the brim 44 abuts against a projection 64, described later, of the operation member 60. The brim 44 may be a single protrusion provided over the entire circumference in the circumferential direction, or may be a plurality of protrusions arranged discretely in the circumferential direction.

The piston member 50 has a flange portion 51 and a coupling convex portion 55 provided behind the flange portion 51. The flange 51 is positioned inside the main tube 30, and the radially outermost end of the flange 51 is in liquid-tight contact with the inner surface 30a of the main tube 30. Thus, the ink containing portion 21 is defined as a space surrounded by the inner surface 30a of the main cylinder 30, the reduced diameter portion 31, and the flange portion 51 of the piston member 50. The flange 51 has a recess 53 recessed rearward from the front end surface 51 a. The coupling projection 55 functions as a coupling portion for coupling the piston member 50 and the operation member 60. The coupling projection 55 is provided with a hole 57 opened rearward. The piston member 50 has a through hole 59 that communicates the recess 53 and the hole 57 on the center axis a. The tube 70 is inserted with play into the through hole 59. That is, the inner diameter of the through hole 59 is larger than the outer diameter of the main body of the tube 70, and thus the tube 70 is held so as to be movable forward and backward with respect to the piston member 50. The hole 57 serves as an introduction portion when the tube 70 is inserted into the through hole 59, and defines a movable range when the tube 70 moves forward and backward with respect to the piston member 50. The through hole 59 may have a cutout formed by cutting in the radial direction in order to ensure smooth flow of ink and air between the ink containing portion 21 and the hole 57.

The operating member 60 is a member that is restricted from moving forward and backward relative to the piston member 50 and is operated by a user when the piston member 50 is moved forward and backward relative to the main cylinder 30. The operating member 60 has a coupling recess 62 that is open at the distal end surface and that fits into the coupling protrusion 55 of the piston member 50. In the illustrated example, the side surface of the coupling concave portion 62 is provided with an engaging concave portion, and the side surface of the coupling convex portion 55 is provided with an engaging convex portion corresponding to the engaging concave portion of the coupling concave portion 62. When the coupling convex portion 55 is inserted into the coupling concave portion 62, the engaging convex portion of the coupling convex portion 55 engages with the engaging concave portion of the coupling concave portion 62, and the piston member 50 is coupled to the operation member 60. The coupling convex portion 55 of the piston member 50 is liquid-tightly attached to the coupling concave portion 62 so that the ink in the inlet 57 does not leak to the outside. The outer peripheral surface of the operating member 60 is provided with a projection 64 projecting outward in the radial direction. The biasing member 25 is disposed between the main tube 30 and the convex portion 64. In the illustrated example, the urging member 25 is a coil spring, and is inserted between the rear end portion of the main tube 30 and the front end portion of the projection 64 in a state of being compressed in the axial direction. Thereby, the operation member 60 is biased rearward with respect to the main tube 30. In the released state of the operating member 60 (state where it is not pressed forward by the user), the projection 64 abuts against the brim 44 of the tail pipe 40 from the front. Therefore, the rear end of the movable range of the operation member 60 is defined by the brim 44.

The pipe 70 is disposed so as to extend through the reduced diameter portion 31 and inside the main tube 30. In any of the released state (see fig. 2) and the pressed state (state pressed forward by the user, see fig. 3) of the operation member 60, the distal end portion 72 of the tube 70 is positioned in front of the reduced diameter portion 31. The rear end 74 of the tube 70 is formed with an enlarged diameter portion 76 formed by expanding the main body of the tube 70 in the radial direction. The outer diameter of the enlarged diameter portion 76 is larger than the inner diameter of the through hole 59 of the piston member 50. The outer diameter of the pipe 70 other than the enlarged diameter portion 76 is smaller than the inner diameter of the through hole 59. Therefore, the tube 70 can move in the front-rear direction while being inserted into the through hole 59, and the tube 70 is positioned at the forefront with respect to the piston member 50 while the enlarged diameter portion 76 is locked to the through hole 59 from the rear. The pipe 70 is hollow, and the portion of the main cylinder 30 ahead of the reduced diameter portion 31 and the hole 57 of the piston member 50 communicate with each other through the pipe 70. The material forming the tube 70 is not particularly limited, but a metal material such as a stainless material can be used as an example.

The fixed block member 80 is fixed to the pipe 70 at the rear of the reduced diameter portion 31. More specifically, the fixed block member 80 is fixed to the outer surface of the pipe 70 at the rear of the reduced diameter portion 31. The fixing block part 80 is formed of an elastic material. As an example of the elastic material, fluororubber can be used. The fixed block member 80 has a closed face 82 at the front. In the illustrated example, the closing surface 82 includes a surface that is inclined with respect to the axial direction and the radial direction as it goes toward the rear in a manner radially away from the tube 70. When the pipe 70 and the fixed block member 80 move forward, the closing surface 82 abuts against the rear inclined surface 31a of the reduced diameter portion 31 to close the reduced diameter portion 31.

The movable block member 90 is clearance fitted with the tube 70 at the rear of the fixed block member 80. That is, the movable block member 90 is movable in the front-rear direction along the tube 70 in the rear of the fixed block member 80. The movable block member 90 is formed in a cylindrical shape as a whole, and the tube 70 is inserted through the inside thereof. The material forming the movable block member 90 is not particularly limited, but a metal material such as a stainless material can be used as an example.

In the ink inhaler 20, the operation member 60 is biased rearward by the biasing member 25 in the release state shown in fig. 2. The protrusion 64 provided on the outer peripheral surface of the operation member 60 abuts against the brim 44 provided in the rear end opening 42 of the tail pipe 40 from the front, thereby restricting further rearward movement of the operation member 60. At this time, the piston member 50 coupled to the operating member 60, the tube 70 held by the piston member 50, the fixed block member 80 fixed to the tube 70, and the movable block member 90 loosely fitted to the tube 70 are also positioned rearward.

When ink is sucked into the ink containing portion 21 of the ink inhaler 20, an ink bottle or the like in which ink is stored is prepared, and in a state where the ink inhaler 20 is attached to the pen tip supporting portion 13, the pen tip 12 is directed downward, and the pen tip supporting portion 13 is immersed in the ink until the ink flow hole 14 and the air flow hole 15 are positioned below the liquid surface of the ink.

In the state where the operation member 60 is directed upward, for example, the operation member 60 is pressed forward (downward) by a finger of the user, and the pressed state shown in fig. 3 is achieved. When the operation member 60 moves forward in the transition from the released state to the pressed state, the piston member 50, the tube 70, the fixed block member 80, and the movable block member 90 also move forward. In this movement, first, the closing surface 82 of the fixed block member 80 abuts against the rear inclined surface 31a of the reduced diameter portion 31 to close the reduced diameter portion 31. Thereby, the tube 70, the fixed block member 80, and the movable block member 90 are stopped. When the operating member 60 further moves forward, the piston member 50 further moves forward. At this time, the air compressed in the ink containing portion 21 passes through the gap between the through hole 59 of the piston member 50 and the tube 70, passes through the hole 57 and the cavity in the tube 70, and flows out from the distal end portion 72 of the tube 70. The air flowing out of the tube 70 is discharged to the outside through the pen tip supporting portion 13. Further, in the case where the through hole 59 of the piston member 50 has a cutout portion formed by cutting in the radial direction, the air flow between the ink containing portion 21 and the hole 57 is sufficiently ensured, and thus the air can be quickly and stably discharged from the ink containing portion 21.

In this state, for example, when the user's finger pressing the operation member 60 forward is removed and the pressing force applied to the operation member 60 is released, the operation member 60 is rapidly retracted by the biasing force of the biasing member 25. In association with this, the piston member 50 also rapidly retreats, and the pressure in the ink containing section 21 becomes a negative pressure. When the operating member 60 and the piston member 50 further retract, the enlarged diameter portion 76 provided at the rear end portion 74 of the tube 70 is locked to the through hole 59 of the piston member 50, and the tube 70, the fixed block member 80, and the movable block member 90 also retract together with the piston member 50. When the closing surface 82 of the fixed block member 80 is separated from the rear inclined surface 31a of the reduced diameter portion 31, the ink in the ink bottle flows into the ink containing portion 21 through the pen tip supporting portion 13 and the reduced diameter portion 31 by the pressure difference between the inside and the outside of the ink containing portion 21.

By repeating this process, ink is sucked into the ink containing section 21. Further, when the operation member 60 is pressed forward in a state where ink is present in the ink containing portion 21, a small amount of ink may flow out from the ink containing portion 21 through the reduced diameter portion 31, but after the reduced diameter portion 31 is closed by the fixing block member 80, ink does not flow out from the ink containing portion 21, and air present in the upper portion of the ink containing portion 21 flows out through the tube 70. After the suction of ink into the ink suction device 20 is completed, the writing instrument 10 is attached to the pen point support portion 13 via the barrel 11, and is in a writable state.

Fig. 4 is a diagram showing the ink inhaler 20 in a state where the pen tip 12 is disposed facing upward. In this state, the tube 70 moves rearward by the action of gravity, and the rear end portion 74 abuts against the lowermost portion (rearmost portion) of the coupling recess 62 of the operating member 60. The fixed block member 80 is largely retracted relative to the reduced diameter portion 31, and the reduced diameter portion 31 is brought into a communicating (non-closing) state. The movable block member 90 is positioned at the lowermost portion (rearmost portion) of the ink containing portion 21 and abuts against the piston member 50. In the present embodiment, the outer diameter D of the movable block member 90_90BIs larger than the inner diameter D of the recess 53 of the piston member 50_53AIs small. Therefore, the movable block member 90 enters the recess 53 and abuts on the lowermost portion (rearmost portion) of the recess 53。

Writing using the writing instrument 10 is usually performed with the pen tip 12 directed downward and the longitudinal direction of the writing instrument 10 inclined with respect to the vertical direction (the direction in which gravity acts). At this time, the central axis a of the ink inhaler 20 is also inclined with respect to the vertical direction. Fig. 5 is a sectional view showing the ink inhaler 20 in a state where the central axis a is inclined with respect to the vertical direction. In the process of the ink inhaler 20 changing from the state shown in fig. 4 to the state shown in fig. 5, the fixed block member 80 moves forward by the action of gravity, whereby the ink in the ink containing portion 21 is pushed out toward the reduced diameter portion 31.

In particular, when the ink in the ink containing portion 21 decreases, even if the ink inhaler 20 is shifted from the state shown in fig. 4 to the state shown in fig. 5, the ink may remain behind the ink containing portion 21 due to the surface tension and not move forward. In the present embodiment, since the ink inhaler 20 includes the movable block member 90, the ink remaining in the rear portion of the ink containing portion 21 is pushed out toward the front by the movement of the movable block member 90 from the rearmost portion of the ink containing portion 21 toward the front. In particular, the outer diameter D of the movable block member 90_90BIs larger than the inner diameter D of the recess 53 of the piston member 50_53AWhen the amount of ink remaining in the recess 53 is small, the ink is pushed out forward as the movable block member 90 moves forward.

In the writing state shown in fig. 5, the central axis a of the ink inhaler 20 is inclined with respect to the vertical direction, whereby the fixing block member 80 is in contact with the inner surface 30a of the main barrel 30 by gravity. During writing, ink is continuously supplied from the ink containing portion 21 to the pen tip 12 through the reduced diameter portion 31 and the ink flow hole 14. As the ink in the ink containing portion 21 decreases, the pressure in the ink containing portion 21 becomes negative. Therefore, the external air flows into the ink containing portion 21 through the air flow hole 15 and the reduced diameter portion 31 by the pressure difference between the inside and the outside of the ink containing portion 21. At this time, the ink moves forward relatively downward, and the air moves rearward above the ink.

In this case, in the conventional push-type ink inhaler, air may not flow properly into the ink containing portion, and smooth flow of ink from the ink containing portion may be inhibited. The present inventors have studied this problem and found that the movable block member may block the inflow of air into the ink containing section.

In the present embodiment, the inner diameter D of the movable block member 90_90AIs the outer diameter D of the tube 70_70B1.5 times or more and 3.5 times or less. Through the inner diameter D_90AIs an outer diameter D_70B1.5 times or more, the movable block member 90 can move downward relatively largely with respect to the fixed block member 80. That is, the central axis of the movable block member 90 can move downward relatively largely with respect to the central axis of the pipe 70. This allows the ink that moves relatively downward to be pushed out forward by the movable block member 90. Further, the gap G1 between the upper portion of the movable block member 90 and the upper portion of the inner surface 30a of the main tube 30 is increased in size. This can effectively prevent the movable block member 90 from blocking the flow of air flowing into the ink containing section 21 through the reduced diameter section 31. And, through the inner diameter D_90AIs an outer diameter D_70B3.5 times or less, preventing the outer diameter D of the movable block member 90_90BToo large, it is also possible to effectively prevent the movable block member 90 from blocking the flow of air flowing into the ink containing section 21 through the reduced diameter section 31.

In particular, in the present embodiment, the thickness T in the radial direction of the movable block member 90₉₀A thickness T in the radial direction of the rear end 84 of the fixed block member 80₈₀The same as or greater than the radial thickness T of the rear end 84 of the anchor block 80₈₀Is small. In this case, in the writing state shown in fig. 5, the gap G1 is larger in size than the gap between the upper portion of the fixing block member 80 and the upper portion of the inner surface 30a of the main tube 30. Therefore, the movable block member 90 can more effectively prevent the flow of air flowing into the ink containing portion 21 through the reduced diameter portion 31 from being obstructed. In addition, when the thickness T is₈₀And a thickness T₉₀The thickness T is constant in the fixed block member 80 and the movable block member 90₈₀And a thickness T₉₀1/2 defined as the difference between the outer and inner diameters of fixed and

movable block members

80 and 90, respectively.

In particular, in the present embodiment, when the center axis line a is arranged in parallel with the horizontal direction in a state in which the fixed block member 80 and the movable block member 90 are positioned at the forefront, the upper end edge 94 of the front end portion 92 of the movable block member 90 is lower than the upper end edge 86 of the rear end portion 84 of the fixed block member 80. In this case, in the writing state shown in fig. 5, the size of the gap G1 is also larger than the gap between the upper portion of the fixing block member 80 and the upper portion of the inner surface 30a of the main tube 30. Therefore, the movable block member 90 can more effectively prevent the flow of air flowing into the ink containing portion 21 through the reduced diameter portion 31 from being blocked.

As another problem, in the conventional push-type ink inhaler, ink may not flow smoothly from the ink containing portion to the pen tip. According to the research of the present inventors, when the ink advances through the reduced diameter portion and reaches the pen tip, the ink may be accumulated behind the reduced diameter portion, which may cause an obstruction to the outflow of the ink.

Fig. 6 is a view showing a section corresponding to the VI-VI line of fig. 5. In the present embodiment, the main tube 30 has a rear rib 33 extending in a plane including the center axis a on the inner surface 30a of the ink containing portion 21. In particular, the main tube 30 has a plurality of rear ribs 33 arranged in the circumferential direction. More specifically, the plurality of rear ribs 33 are arranged at equal angular intervals (equal angular intervals) in the circumferential direction. The rear rib 33 is provided at a position of the ink containing portion 21 excluding the movable range of the piston member 50. The rear rib 33 is provided at a position of the rear inclined surface 31a of the reduced diameter portion 31 except for a range where the closed surface 82 of the fixed block member 80 abuts. Each rear rib 33 extends linearly in the axial direction when viewed from the center axis a. Further, the rear ribs 33 may extend linearly in a direction inclined with respect to the axial direction when viewed from the central axis a, or may extend in a curved line when viewed from the central axis a.

Since the main tube 30 has the rear rib 33, the ink in the ink containing portion 21 is guided toward the reduced diameter portion 31 along the rear rib 33 in the writing state. In the writing state shown in fig. 5, the lower portion of the fixed block member 80 abuts against the rear rib 33, and a gap G2 is formed between the lower portion of the fixed block member 80 and the lower portion of the inner surface 30a of the main tube 30. Therefore, the ink in the ink containing portion 21 can flow smoothly toward the reduced diameter portion 31 through the gap G2. This effectively prevents ink from being accumulated behind the reduced diameter portion 31.

In the conventional push-type ink inhaler, the fixed block member 80 is stuck to the inner surface 30a of the main cylinder 30, and the movement of the fixed block member 80 toward the reduced diameter portion 31 may be hindered. In the present embodiment, the main tube 30 has the rear rib 33, and the gap G2 is formed between the lower portion of the fixing block member 80 and the lower portion of the inner surface 30a of the main tube 30, whereby the fixing block member 80 can be prevented from sticking to the inner surface 30a of the main tube 30.

Further, in the conventional push-type ink inhaler, the fixed block member 80 is fitted into a boundary portion between the rear inclined surface 31a of the reduced diameter portion 31 and the rear parallel portion 30a1 which is a portion of the inner surface 30a of the main cylinder 30 parallel to the central axis a, and thereby the fixed block member 80 may be prevented from moving toward the reduced diameter portion 31. In the present embodiment, since the main tube 30 has the rear rib 33, the fixing block member 80 can be prevented from being fitted into the boundary portion between the rear inclined surface 31a of the reduced diameter portion 31 and the rear parallel portion 30a1, and the fixing block member 80 can be stably guided toward the reduced diameter portion 31.

In particular, in the present embodiment, at least a part of the rear rib 33 is provided on the rear inclined surface 31a of the reduced diameter portion 31. In this case, the ink in the ink containing portion 21 is more effectively guided toward the reduced diameter portion 31 along the rear rib 33.

In particular, in the present embodiment, the rear rib 33 includes a portion where the distance from the center axis a in the radial direction decreases toward the front in the rear parallel portion 30a 1. In this case, the fixed block member 80 is guided so as to approach the central axis a as it goes forward. Therefore, the fixed block member 80 can be more stably guided toward the reduced diameter portion 31.

The present inventors have conducted studies on the problem that in a conventional push-type ink inhaler, air does not appropriately flow into the ink containing portion and the smooth flow of ink from the ink containing portion may be inhibited, and as a result, they have found that the air heading into the ink containing portion is retained in front of the reduced diameter portion, thereby inhibiting the air from flowing into the ink containing portion.

Fig. 7A is a view showing an example of a cross section corresponding to the line VII-VII in fig. 5, and fig. 7B is a view showing another example of a cross section corresponding to the line VII-VII in fig. 5. In particular, fig. 7A and 7B show the ink inhaler 20 in a cross section perpendicular to the central axis a. In the present embodiment, the main tube 30 has a front inclined surface 31b inclined with respect to the axial direction and the radial direction or a front rib 34 extending in a plane including the central axis a of the main tube on an inner surface 30a in front of the reduced diameter portion 31.

In the example shown in fig. 7A, the main tube 30 has a front rib 34. In particular, in the illustrated example, the main tube 30 has a plurality of front ribs 34 arranged in the circumferential direction. More specifically, the plurality of front ribs 34 are arranged at equal angular intervals (equal angular intervals) in the circumferential direction. Each of the front ribs 34 extends linearly in the axial direction when viewed from the center axis a. Further, the front ribs 34 may extend linearly in a direction inclined with respect to the axial direction when viewed from the central axis a, or may extend in a curved line when viewed from the central axis a.

Since the main tube 30 has the front rib 34, air (air bubbles) heading for the ink containing portion 21 is guided toward the diameter-reduced portion 31 along the front rib 34 in the writing state. This can suppress the air heading for the ink containing portion 21 from being accumulated in front of the reduced diameter portion 31, and can promote the air to flow into the ink containing portion 21. The ink flowing out of the ink containing portion 21 is guided toward the pen tip supporting portion 13 along the front rib 34. This also promotes the outflow of ink from the ink containing portion 21.

The inventors speculate as follows that the principle of such an effect is produced. When the main cylinder 30 has such a front rib 34, the distance between the front portion of the tube 70 and the inner surface 30a of the main cylinder 30 is reduced when writing is performed with the pen tip 12 directed downward and the longitudinal direction of the writing instrument 10 inclined with respect to the vertical direction. Here, assuming that the distance between the tube 40 and the inner surface 30a is r and the contact angle between the ink and the inner surface 30a is θ, the drag force P of the ink due to the surface tension T of the ink can be expressed as the following equation.

P＝(2×T×cosθ)/r

Therefore, it can be estimated that the traction force P of the ink increases as the distance r between the tube 40 and the inner surface 30a decreases.

In particular, in the illustrated example, the front rib 34 has a corner 35 facing the central axis a in a cross section perpendicular to the central axis a. By providing the corner portion 35 in the front rib 34, the air bubbles contacting the corner portion 35 can be prevented from adhering to the inner surface 30a of the main tube 30 and being accumulated in front of the reduced diameter portion 31 due to the surface tension acting on the air bubbles.

In particular, in the illustrated example, the front rib 34 includes a portion whose distance from the central axis a in the radial direction becomes smaller toward the rear in the front parallel portion 30a2 parallel to the central axis a in the inner surface 30 a. In this case, the air heading toward the ink containing portion 21 is guided along the front rib 34 toward the rear so as to approach the center axis a in front of the reduced diameter portion 31. Therefore, the air can be more effectively suppressed from being accumulated in front of the reduced diameter portion 31.

In the example shown in fig. 7B, the main tube 30 has a front inclined surface 31B. The front inclined surface 31b is a surface extending obliquely with respect to the axial direction and the radial direction so as to be directed outward in the radial direction as it goes forward. Since the main tube 30 has the front inclined surface 31b, air (air bubbles) heading to the ink containing portion 21 is guided toward the reduced diameter portion 31 along the front inclined surface 31b in the writing state. This can suppress the air heading for the ink containing portion 21 from being accumulated in front of the reduced diameter portion 31, and can promote the air to flow into the ink containing portion 21. The ink flowing out of the ink containing portion 21 is guided toward the pen tip supporting portion 13 along the front inclined surface 31 b. This also promotes the outflow of ink from the ink containing portion 21.

In particular, in the illustrated example, the front inclined surface 31b has a groove portion 32 extending in a plane including the central axis a of the main tube 30. In particular, in the illustrated example, the front inclined surface 31b has a plurality of grooves 32 arranged in the circumferential direction. More specifically, the plurality of groove portions 32 are arranged at equal angular pitches (equal angular intervals) in the circumferential direction. Each groove portion 32 extends linearly in the axial direction when viewed from the center axis a. Further, the groove portions 32 may be linearly extended in a direction inclined with respect to the axial direction when viewed from the central axis a, or may be curved when viewed from the central axis a.

Since the front inclined surface 31b has such a groove portion 32, air (bubbles) heading to the ink containing portion 21 is guided toward the reduced diameter portion 31 along the groove portion 32. This can further suppress the air heading for the ink containing portion 21 from being trapped in front of the reduced diameter portion 31, and can further promote the air from flowing into the ink containing portion 21. The ink flowing out of the ink containing portion 21 is guided toward the pen tip supporting portion 13 along the groove portion 32. This can further promote the outflow of ink from the ink containing portion 21.

In particular, in the illustrated example, the circumferential width of the groove portion 32 decreases toward the front. This increases the capillary force in the groove portion 32 toward the front. Therefore, the ink flowing out of the ink containing portion 21 is sucked forward along the groove portion 32. This can further promote the outflow of ink from the ink containing portion 21.

In addition, various modifications may be made to the above embodiments. Hereinafter, modifications will be described with reference to the drawings as appropriate. In the following description and the drawings used in the following description, the same reference numerals as those used for corresponding portions in the above-described embodiments are used for portions that can be configured in the same manner as in the above-described embodiments, and redundant description is omitted.

Fig. 8 is a longitudinal sectional view showing a modification of the ink inhaler 20, and fig. 9 is a transverse sectional view corresponding to the line IX-IX of fig. 8.

In the present modification, the main tube 30 of the ink inhaler 20 has a plurality of front ribs 34. In particular, in the example shown in fig. 9, the main tube 30 has four front ribs 34 arranged at equal angular intervals in the circumferential direction. That is, in the illustrated example, two front ribs 34 adjacent in the circumferential direction are arranged at an angular pitch of 90 degrees from each other.

In the example shown in fig. 9, the front ribs 34 are arranged with a space S1 therebetween in the circumferential direction. Here, the interval S1 refers to the length in the circumferential direction on the inner surface 30a of the main cylinder 30. In this modification, the interval S1 is 2.7mm or more. That is, the interval S1 between two front ribs 34 adjacent in the circumferential direction is 2.7mm or more.

When the distance S1 is 2.7mm or more, a sufficient distance is secured between the adjacent two front ribs 34, and therefore, air bubbles are prevented from being trapped between the two front ribs 34. That is, the flow of the air bubbles is promoted by suppressing the air bubbles from being accumulated in the front portion of the reduced diameter portion 31. This can promote the outflow of ink from the ink containing portion 21 due to the rearward movement of the bubbles.

The interval S1 between two circumferentially adjacent front ribs 34 is preferably 2.7mm to 4.7 mm. If the distance S1 is 4.7mm or less, the distance between the front portion of the tube 70 and the inner surface 30a of the main tube 30 can be reduced appropriately when the longitudinal direction of the writing instrument 10 is inclined with respect to the vertical direction. Therefore, the traction force P of the ink due to the surface tension T of the ink can be effectively increased. Further, the interval S1 is more preferably 3.3mm or more and 3.7mm or less.

Fig. 10 is a cross-sectional view corresponding to the X-X line of fig. 8. In the present modification, the main cylinder 30 of the ink inhaler 20 has a plurality of rear ribs 33. In particular, in the example shown in fig. 10, the main tube 30 has five rear ribs 33 arranged in the circumferential direction with an equal angular pitch. That is, in the illustrated example, two rear ribs 33 adjacent in the circumferential direction are arranged so as to have an angular pitch of 72 degrees from each other.

In the example shown in fig. 10, the rear ribs 33 are arranged with a space S2 therebetween in the circumferential direction. Here, the interval S2 refers to the length in the circumferential direction on the inner surface 30a of the main cylinder 30. In this modification, the interval S2 is 2.7mm or more. That is, the interval S2 between two rear ribs 33 adjacent in the circumferential direction is 2.7mm or more.

When the distance S2 is 2.7mm or more, a sufficient distance is secured between the two adjacent rear ribs 33, and therefore, air bubbles can be prevented from being blocked between the two rear ribs 33. That is, the bubbles are suppressed from staying at the rear portion of the reduced diameter portion 31, and the flow of the bubbles is promoted. This can promote the outflow of ink from the ink containing portion 21 due to the rearward movement of the bubbles.

The interval S2 between two circumferentially adjacent rear ribs 33 is preferably 2.7mm to 4.7 mm. If the distance S2 is 4.7mm or less, the distance between the rear portion of the small tube 70 and the inner surface 30a of the main tube 30 can be reduced appropriately when the longitudinal direction of the writing instrument 10 is inclined with respect to the vertical direction. Therefore, the traction force P of the ink due to the surface tension T of the ink can be effectively increased. Further, the interval S2 is more preferably 3.3mm or more and 3.7mm or less.

Description of the reference symbols

10: a writing instrument; 11: a shaft cylinder; 12: a pen point; 13: a pen point support portion; 20: an ink inhaler; 21: an ink containing section; 25: a force application member; 30: a main barrel; 30 a: an inner surface; 30a 1: a rear parallel portion; 30a 2: a front parallel portion; 31: a diameter reducing portion; 31 a: a rear inclined surface; 31 b: a front inclined surface; 32: a groove part; 33: a rear rib portion; 34: a front rib section; 35: a corner portion; 40: a tail cylinder; 42: a rear end opening part; 44: an eave portion; 50: a piston member; 51: a flange portion; 51 a: a front end face; 53: a recess; 55: a connecting convex part; 57: an aperture; 59: a through hole; 60: an operating member; 62: a connecting concave part; 64: a convex portion; 70: a tube; 72: a front end portion; 74: a rear end portion; 76: an expanding portion; 80: a fixed block component; 82: a closed face; 84: a rear end portion; 86: an upper end edge; 90: a movable block member; 92: a front end portion; 94: and an upper end edge.

Claims

1. An ink inhaler, comprising:

a main cylinder having a reduced diameter portion on an inner surface thereof, the main cylinder defining an ink accommodating portion behind the reduced diameter portion;

a piston member disposed to be movable forward and backward with respect to the main cylinder;

a tube that extends inside the main cylinder through the inside of the reduced diameter portion and is held so as to be movable forward and backward with respect to the piston member; and

a fixed block member fixed to the pipe at the rear of the reduced diameter portion,

the main cylinder has a front inclined surface inclined with respect to the axial direction and the radial direction on an inner surface in front of the reduced diameter portion, or has a front rib extending in a plane including a central axis of the main cylinder.

2. The ink inhaler according to claim 1,

the main cylinder has the front inclined surface,

the front inclined surface has a groove portion extending in a plane including a central axis of the main tube.

3. The ink inhaler according to claim 2,

the main cylinder has a plurality of the groove portions arranged in a circumferential direction.

4. The ink inhaler according to claim 2 or 3,

the circumferential width of the groove portion decreases toward the front.

5. The ink inhaler according to claim 1,

the main cylinder has the front rib portion,

the front rib has a corner facing the central axis in a cross section perpendicular to the central axis.

6. The ink inhaler according to claim 1 or 5,

the main cylinder has the front rib portion,

in a front parallel portion of the inner surface that is parallel to the central axis, the front rib includes a portion whose distance from the central axis in a radial direction decreases toward the rear.

7. The ink inhaler according to claim 1, 5 or 6,

the main tube has a plurality of the front ribs arranged in a circumferential direction.

8. The ink inhaler according to claim 7,

the interval between two of the front ribs adjacent in the circumferential direction is 2.7mm or more.

9. The ink inhaler according to any one of claims 1 to 8,

the main tube has a rear rib extending in a plane including a central axis of the main tube on an inner surface of the ink containing portion.

10. The ink inhaler according to claim 9,

the main tube has a plurality of the rear ribs arranged in a circumferential direction.

11. The ink inhaler according to claim 10,

the interval between two of the rear ribs adjacent in the circumferential direction is 2.7mm or more.