JP3681203B2 - Knock-type writing instrument - Google Patents

Description

[0001]
[Industrial application fields]
In the so-called knock-type writing instrument in which a refill as a writing body is projected by pressing the knock rod at the rear end, the inner cylinder and the locking portion inside the shaft cylinder are released when stored in the pocket. The present invention relates to a knock type writing instrument having an improved safety mechanism that does not contaminate clothes because the refill is stored. In particular, the present invention relates to an improvement of a knock-type ballpoint pen aimed at improving the certainty of operation and operability in the case of an inexpensive configuration.
[0002]
[Prior art]
In the conventional capless knock type ballpoint pen that does not require cap removal, the front end surface of the shaft is open, and by pushing the knock part, the refill protrudes and the structure is written. If the user forgets to store the refill when it is stored in the pocket, the refill remains protruding out of the shaft, and there is an accident that stains the pocket with ink. In order to solve this problem, the clip ball and the projection inside the shaft are locked, so that when writing tools are inserted into the pockets, the structure of the refill is always stored, and the shaft is provided with a window. There has been proposed a device in which a locking portion is provided in the ball portion to achieve the same operation. However, these have disadvantages such as a metal clip that requires processing of windows and locking parts, which is expensive and has problems with workability, sacrifices the durability of the clip's springiness, and increases the number of parts. Existed. In particular, in the safety mechanism that prevents the clothes from being knocked by the knock type, when the refill is protruded by pressing the knock bar, it is locked by pushing the rear end of the clip and lifting the clip ball. The one that releases the refill and accommodates the refill is generally adopted. In this case, the spring imparting portion of the clip has a strong spring property in consideration of repeated durability of locking and releasing. Therefore, it was difficult to set a load that was easy to use due to the force required for release, and when a direct liquid refill was installed, the inside of the refill was affected by the impact on the refill at the time of release. There is a risk that the ink will be displaced, leaked, or air may be trapped in the tip, resulting in writing damage. It is present. In addition, it was desired to have a so-called double knock type writing instrument with a safety mechanism that repeats protrusion and storage of the refill simply by repeatedly pressing the knock bar which is easy and excellent in operability in terms of operability. There was no good writing instrument.
[0003]
[Problems to be solved by the invention]
Therefore, the present invention is mainly aimed at improving the popular ballpoint pen, and the smooth operation in the case of the refill projecting operation and storing operation, and the accident that stains clothes when stored in the pocket without disturbing writing It is desired to solve the problem of assembling as well as the problem of cost by using a very inexpensive part shape and configuration as a mechanism that makes it easy to project and store the refill. In addition, even if the clip is made of resin, there is a demand for ensuring a reliable operation with weak springiness that is difficult to creep, a request for ensuring a reliable operation with a good feeling of operation, and further refilling. To solve the problem of providing a knock-type writing instrument that satisfies the need to reduce knock impact.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the knock type writing instrument of the present invention has a refill having a writing portion at the tip, a spring 6 for urging it backward, and a knock bar 5 protruding from the shaft cylinder 1 in conjunction with the refill. When the knock bar 5 is pressed to project the refill from the front part of the shaft cylinder 1, the clip is brought into a protruding state, and the locking balls 2-a of the clip provided on the inner cylinder 2 are engaged with the locking ribs 3 of the rotor 3. The protruding state is maintained by locking to -a. A rotor 3 for supporting the refill is provided between the refill in front of the knock bar 5, and the knock bar 5 and the rotor 3 are knock cams 5-a and knock cams 3-c which are cam slopes corresponding to the rotor 3 respectively. And the rotor is configured to rotate only in a predetermined direction by a predetermined angle by a knocking operation forward in the axial direction. Further, when the pressing after the knocking operation is stopped, the refill is always urged rearward by the spring 6, and the above-mentioned knock bar is formed by the cam projection 3-b of the rotor 3 and the cam 2-c of the inner cylinder 2 corresponding thereto. 5 and the rotor 3 are rotated in the same direction. That is, the rotor 3 rotates at a predetermined angle, makes one round at a certain time (in the embodiment, with two knocks), and repeats the operation. In order to ensure these operations, the cam surface of the cam 2-c of the inner cylinder 2 described above is formed with a step 2-g that is not locked with the cam projection 3-b, and the locking ball 2-a And the locking rib 3-a so as not to hinder the locking, and the locking ball 2-a and the window 1-a of the shaft tube 1 are respectively provided with a ball flat portion 2-h and a shaft flat portion. With the 1-d provided , the flat portion 2-h and the shaft flat portion 1-d are in contact with each other in the state where the locking ball 2-a and the shaft tube 1 are immersed. Increased sex. Further, in the case of a direct liquid refill containing medium-viscosity ink, in which impact at the time of storage tends to be a problem, the viscosity at a shear rate of 200 ( S ⁻¹ ) at 25 ° C. is from 10 mPa · S to 3000 mPa · S. [Preferably a viscosity of 30 to 1000 mPa · s having shear thinning viscosity] Medium viscosity ink 11 and a grease-like follower 9 that hardly volatilizes behind the refill, and a specific gravity substantially equal to that of the follower 9 so as to float on the follower 9 The follower bar 8 is built in, and the writing ball 14-a is held inside the chip 14 holding the writing ball 14-a serving as a writing part by a circumferential caulking, and the writing ball 14-a is always provided. the built-in chip spring 15 for pressing to form a ball valve mechanism by a circumferential caulking portion 14-b and writing ball 14-a Cage, added the backflow prevention mechanism by the valve structure of the check ball 13 and the joint 12 in order to ensure the backflow prevention effect. When the hot-melt type tip sealant 16 that melts at 80 ° C. to 150 ° C. is attached to the tip of the writing portion, troubles due to transportation can be prevented. Further, in order to assemble at a low cost and to omit parts, the protrusion 2-f formed integrally with the inner cylinder 2 and the stopper groove 1-c of the shaft cylinder 1 are engaged, so that the internal mechanism of the shaft is retracted. In the case of regulation, the snap fit can be assembled only by an insertion operation, and a low-cost knock-type writing instrument in which the mouth 17 is omitted can be obtained.
[0005]
【Example】
The illustrated embodiment will be described in detail below. 1 to 8 show an embodiment of the present invention. As shown in the figure, a joint is press-fitted into the tube end side of the refill that stores ink in a tube made of transparent or translucent resin, and a ball receiving seat having an ink introduction hole is provided in the approximate center of the inside of the tip. In the normal writing, the check ball is loosely fitted in the valve chamber formed by the axial rear end and the seat, and the check ball is upwardly connected to the ball serving as the writing portion. This is a knock-type writing instrument having a so-called medium-viscosity ball-point pen refill that has a ball-point re-fill with a structure that prevents back flow of ink by being in close contact with a receiving seat.
[0006]
This refill is a direct liquid refill containing medium-viscosity ink, which is particularly susceptible to impact during storage. Viscosity of 10 to 3000 cp, preferably 30 to 1000 cp of medium viscosity ink imparted with shear thinning, which is said to be pseudoplastic, and grease consisting of a mixture of a viscosity modifier and mineral oil such as polybutene and liquid paraffin which does not volatilize behind the refill. And a follower rod made of resin such as PP or PE having a specific gravity almost equal to that of the follower so that it floats on the follower, and a chip that holds the writing ball as the writing part has a writing ball inside. with Ru is retained by the circumferential caulking portion, a built-in chip spring for pressing at a load of 40g to about 1g, circumferential caulking portion between the writing ball and the ball valve mechanism comprising a sealing of a ball To improve impact resistance, prevent ink volatilization and prevent ink backflow. This tip spring is usually a spring with a linear part integrated at the tip to directly press a very small writing ball of φ0.3 to φ1.2. Is secured by caulking. When hot tip type sealant 16 that melts at 80 ° C to 150 ° C is attached to the tip for the purpose of protecting the pen tip during transport or preventing volatilization, troubles due to improved long-term storage and transportation to the user Can be prevented.
[0007]
This knock-type writing instrument has a refill having a writing portion at the tip, a spring for urging the refill, and a knock bar that abuts against the rear end surface of the refill and protrudes from the shaft tube. When the knock bar is pressed and the refill is protruded from the front part of the shaft cylinder, it becomes a protruding state. At this time, the locking balls of the clip provided on the inner cylinder engage with the locking ribs of the rotor inside the shaft cylinder. And keep the protruding state. A rotor is provided between the refill in front of the knock bar, and the knock bar and the rotor having a detent with respect to the inner cylinder are appropriately loosely fitted so as to be interlocked with the refill by a knocking operation, and also in the reverse direction. The clip is restricted by a receiving portion of the clip cylinder so that it can be operated only within a predetermined knock stroke.
[0008]
The knock bar and the rotor each have a knock bar cam and a knock cam, which are cam slopes corresponding to the knock bar and the rotor, respectively, and the rotor is configured to rotate only in a predetermined direction by a predetermined angle by a knock operation forward in the axial direction. . Further, when the pressing after the knocking operation is stopped, the refill is always urged backward by the spring, and the rotation of the above-described knocking rod and the rotor is performed in the same direction by the cam projection of the rotor and the corresponding cam of the inner cylinder. Rotate. In other words, the rotor rotates at a predetermined angle, makes one round at a certain point (in the embodiment, with two knocks), and repeats the operation. The shape and angle of each cam slope required for these operations is selected as appropriate, and the stopper for the knock bar and the stopper for the stopper by the guide groove of the inner cylinder and the receiving part for the stopper at the rear of the shaft are also appropriate. The shape can be selected. In the present invention, in order to further ensure the operation, the knocking operation for locking with a step on the locking surface of the cam inclined surface and the locking rib is locked forward of the locking ball. Since the rib is moving and the cam is stepped when it is locked when the pressure of the knock bar is stopped, the cam does not hinder the locking between the ball portion and the rib . Further, since the locking balls are normally provided with a spring property that always goes inward in the axial radial direction, flat portions corresponding to the locking balls and the window portion of the shaft are provided as receiving surfaces at this time. As a result, even if there is some variation in the members, it is possible to provide a knocking and locking mechanism that has no functional problem.
[0009]
If you forget to store the refill in the refill projecting state and try to insert it into the pocket, you can lift the retaining ball of the clip provided on the inner cylinder upward to engage the engaging rib of the rotor and the clip provided on the inner cylinder. Since the stop ball is released and the lock is released, the refill moves in the storage direction. Due to the cam projection of the rotor and the cam of the inner cylinder, the rotor is retracted while rotating and retracted to the rearward restricting position in the axial direction, and the refill interlocked with the rotor is stored. At this time, the rotor is set in the rotational direction at the same position as in the initial state, and when the knock bar is pressed again, the operation in the protruding direction can be started. Also, if the inner cylinder is provided with a protrusion fixed by molding or press-fitting, and the inner cylinder and knocked rod, rotor, refill and other built-in objects are restricted by the protrusion and the stopper groove of the shaft cylinder, it is attached during assembly. It can be assembled only by snap-fit by insertion work, or the user can take out the mechanism part and refill by pushing the protrusion with a sharp protrusion so that the refill can be replaced, and it is possible to develop inexpensive products without the mouth Become.
[0010]
As another embodiment of the present invention, the present invention can be applied to a writing instrument in which the pocket becomes dirty when the writing portion is exposed. In addition to what has been described above, so-called water-based ballpoint pens that use batting that is normal aqueous ink and fiber bundles in the ink occlusion body, and oil-based ballpoint pens that use oil-based inks with slightly lower viscosity than usual In addition, a knock-type writing instrument using a fiber bundle at the pen tip or a so-called sign pen or marker refill utilizing the capillary phenomenon inside, or a metal spring plate to further reinforce the spring property of the inner cylinder Anything added to can be used as appropriate. Similar effects of the present invention can be expected even in these examples.
[0011]
[Action]
In the embodiments, the operation of the present invention will be described. In a knock-type ballpoint pen that can be written by pushing the knock bar protruding backward from the shaft, the refill as a writing body protrudes from the tip of the shaft and locks with the locking ball of the clip provided on the inner cylinder Since the rib is locked to maintain the protruding state of the refill, when the clip of the clip provided on the inner cylinder is lifted, the lock is released and the refill is automatically stored. It is possible to prevent the clothes from being soiled by inserting them into the pockets with the spilling out. In addition, since the pressing force of the clip part lighter than before can be set, the operational feeling can be improved and the locking projection does not protrude outside the shaft, so that it can be easily inserted into and removed from the pocket. It is possible to prevent creeping of the clip part of the inner cylinder, and even if it is creeped, the inner cylinder operates lightly by rotating operation, so that functional problems do not occur and a step is provided on the cam slope. This prevents the locking ball and the locking rib from being locked. In addition, by providing a flat portion at a location facing the shaft cylinder of the locking ball and providing a shaft flat portion at a location facing the clip of the shaft tube, the locking ball is engaged in a state where it is immersed in the shaft tube. The flat portion of the stop ball and the shaft flat portion of the shaft tube are in contact with each other, and the certainty of locking is improved by absorbing the variation in the position to be locked. Furthermore, since the protrusion and storage are repeated only by the operation of the knock part, not only a special operation explanation is not given to the user but the operability can be improved, and the impact at the time of return is considerably weakened by the cam slope and the user's finger of the knock part. Therefore, it is possible to mount a medium-viscosity refill, which has been impossible in the past.
[0012]
【The invention's effect】
The configuration and operation of the knock type writing instrument of the present invention are as described above, and it not only satisfies the functions of a highly safe knock type writing instrument that has the effect of not causing a serious accident such as soiling clothes, but is also used by the user. It is possible to provide an easy-to-use writing instrument that can be used easily. Further, it becomes possible to reduce the effect of the creep phenomenon of the clip, and even if it is creeped, the inner cylinder operates lightly by the rotating operation, so that no functional problem occurs. Not only is the structure of the parts simplified, but there is no need to select an expensive resin with high heat resistance, so it is possible to provide a stable product considering long-term durability that is inexpensive and has good functionality. In addition, it is possible to provide a satisfactory knock-type writing instrument that can be inserted into and removed from the pocket or operated in a knocking manner and is inexpensive.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an entire writing instrument according to an embodiment of the present invention.
FIG. 2 is a longitudinal sectional view showing a rear end portion of a writing instrument according to an embodiment of the present invention.
FIG. 3 is a longitudinal sectional view showing a tip portion of a writing instrument according to an embodiment of the present invention.
FIG. 4 is an external view of an inner cylinder part that is an embodiment of the present invention.
FIG. 5 is a lower external view (in the direction of arrow A) of the inner cylinder part according to the embodiment of the present invention.
FIG. 6 is a detailed external view (locking ball portion) of the inner cylinder part according to the embodiment of the present invention.
FIG. 7 is an external view of a rotor that is an embodiment of the present invention.
FIG. 8 is a developed schematic view of a cam slope of a writing instrument according to an embodiment of the present invention.
FIG. 9 is an operation schematic diagram of a writing instrument cam slope according to an embodiment of the present invention.
[Explanation of symbols]
1 Shaft cylinder 1-a Window 1-b Guide groove 1-c Stopper groove 1-d Shaft flat part 2 Inner cylinder 2-a Locking ball 2-b Guide groove 2-c Cam 2-d Non-rotating groove 2-e Standing part 2 -f Protrusion 2 -g Step 2 -h Flat part 3 Rotor 3 -a Locking rib 3 -b Cam protrusion 3 -c Knock cam 3 -d Flow path 4 -a Undercut A
4-b Undercut B
4-c Undercut C
5 knock bar 5-a knock bar cam 5-b detent 6 return spring 7 tail plug 8 follower bar 9 follower 10 tube 11 ink 12 joint 13 check ball 14 tip 14-a writing ball 14-b caulking part 15 tip spring 15-a Linear part 15-b Spring part 16 Tip sealant

Claims (3)

It has a refill having a writing part at the tip, a spring 6 for biasing it backward, and a knock bar 5 that is loosely fitted so as to be interlocked with the refill and protrudes from the rear end of the shaft tube 1 . A rotor 3 for supporting the refill is provided in between, and the knock bar 5 is pressed to cause the refill to protrude from the front portion of the shaft tube 1 so that the protruding state is maintained. In the knock type writing instrument having a so-called double knock mechanism for storing the refill, the clip engaging ball 2-a provided on the inner cylinder 2 and the rotor 3 interlocking with the knock bar 5 inside the shaft are provided . When the locking rib 3-a is locked, the protruding state of the writing portion of the refill is maintained, and when the locking ball 2-a is lifted up, a safety mechanism is configured in which the refill is accommodated and knocked when protruding. Knock of stick 5 Rotation of the rotor 3 by the cam 2-c of the cam projection 3 over b and the inner cylinder 2 of the rotor 3 in the case of storing the rotating direction of the rotor 3 by the knocking cam 3 over c rod cam 5-a and the rotor 3 The cams are arranged so that both of the directions are the same, and the rotor 3 integrally having the locking rib 3-a is rotated in the same direction at a predetermined angle by repeating knocking, and the above-described inner cylinder The cam surface of the second cam 2c is formed with a step 2g that does not engage with the cam projection 3b, so that the locking ball 2a and the locking rib 3a can be locked. Knock-type writing instrument characterized by not obstructing . Engaging ribs 3-a of the rotor 3 does not protrude from the outer diameter of the barrel 1, with is immersed into the Kakaritomedama 2-a clip provided on the inner cylinder 2 in the barrel 1, the A flat portion 2-h that is a flat surface is provided in a portion of the locking ball 2-a that faces the shaft tube 1, and a shaft flat portion 1-d that is a flat surface in a portion of the shaft tube 1 that faces the clip. 2. The flat portion 2-h and the shaft flat portion 1-d are in contact with each other in a state where the locking ball 2-a is immersed in the shaft cylinder 1. Knock-type writing instrument. Knock-type writing instrument of the ball point pen type according to claim 1 or 2, characterized in that the built-in refill and refill to satisfy the structure of the following (1) to (3).
(1) Medium viscosity ink 11 at an ink viscosity of 10 mPa · S to 3000 mPa · S at a shear rate of 200 ( S ⁻¹ ) at 25 ° C. and a grease-like follower 9 that is less likely to volatilize behind the refill and the follower 9 are substantially equivalent. And a follower bar 8 having a specific gravity of 5 mm.
(2) has a writing ball 14-a serving as a writing section, with Ru is retained the writing ball 14-a by circumferential caulking portion 14 over b inside the chip 14 to hold it, about 1g The tip spring 15 that is pressed by a load of 40 g to 40 g is built in, and a ball valve mechanism is formed by the circumferential crimping portion 14-b and the writing ball 14-a.
(3) The tip spring 15 is provided with a straight portion 15-a integrally with the spring portion 15-b at the rear end at a portion in contact with the writing ball 14-a.

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