BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a knock-type ball-point pen in a non-pressurized state according to an embodiment of the invention.
FIG. 2 is an enlarged fragmentary sectional view of a main portion of the pen in the non-pressurized state.
FIG. 3 is an enlarged perspective half-sectioned view of pressurizing member,
FIG. 4 is a sectional view of the pen in an initial pressurized state,
FIG. 5 is an enlarged sectional fragmentary view of the main portion of the pen in the initial pressurized state.
FIG. 6 is an enlarged perspective half-sectioned view of the pressurizing member in a compressive deformation state,
FIG. 7 is a sectional view of the pen in a maximum pressurized state, and
FIG. 8 is a sectional view of the pen in a pressurized state at the time of using the pen.
DESCRIPTION OF PREFERRED EMBODIMENTS
Hereinafter, the invention will be described in detail with reference to embodiments thereof showing a knock-type ball-point pen as an example and the drawings.
In FIG. 1, “left side” is defined as “the front”, and “right side” is defined as “the rear” of the pen.
As shown in the FIG. 1, in a ball-point pen 1 of the invention, the pen holder is formed of a barrel 2 and a front member 3 screwed onto a front end section 2a of the barrel 2, and a pen refill unit 4 is loaded in the pen holder.
The pen refill unit 4 includes an ink containing tube 6 filled with ink 5 as a medium for writing, a pen tip 7 loaded on a front end portion 6a of the ink containing tube 6. The pen tip 7 is configured to protrude and retreat from the front aperture section 3a of the front member 3 to the outside by operating the pen refill unit 4 which will be mentioned later.
A rear opening portion 6b of the ink containing tube 6 is kept and held by a holder 8 which is a member sliding in front and rear axial direction in the barrel 2. The holder 8 is biased toward the rear so that the pen tip 7 of the pen refill unit 4 by a compression spring 9 is contained in an inside of the front member 3.
A knock mechanism 10 is assembled into an inside of a rear end section 2b of barrel 2. The knock mechanism 10 includes a knock section 11, a compression spring 12 biased to the rear so as to protrude the knock section 11 from the rear end section 2b of the barrel 2, a knock bar 13 cooperating with the pressing operation of the knock section 11 which resists against a bias force of the compression spring 12 and the opening operation thereof, a cam mechanism portion 14 interlocking with the knock bar 13, and a rotor 15 cooperating with the cam mechanism portion 14. In that case, the spring force of the compression spring 12 is set to be smaller than the spring force of the compression spring 9.
That is, the knock mechanism 10 is a known mechanism which presses and opens the knock bar 13 against the bias force of the compression spring 12 by the knocking operation of the knock section 11, and thus driving the rotor 15 by the cam mechanism portion 14, so as to spear and disappear the pen tip 7 of the pen refill unit 4 in a protruded state.
A press pump mechanism 16 is disposed between the rear opening portion 6b of the ink containing tube 6 and a front end portion 15a of the rotor 15. As shown in FIG. 2, the press pump mechanism 16 includes a pressing member 17 following the drive of the rotor 15, and a pressurizing member 18 disposed between the pressing member 17 and the rear opening portion 6b of the ink containing tube 6. A front end portion 17a of the pressing member 17 is protruded toward the front to form a cone shape, and the portion in a function as a cap capable of blocking a front aperture 21b of a rear cylinder portion 21 in an elastic cylindrical member 19 forming the pressurizing member 18 which will be mentioned later.
The pressurizing member 18 is formed of the elastic cylindrical member 19 made of an elastomer material such as rubber. As shown in the FIG. 3, the elastic cylindrical member 19 includes a large-diameter front cylinder portion 20 of which a rib-shaped front end 20a is directly contacted with a slider 8 including the rear opening portion 6b of the ink containing tube 6 in an airtight state and communicates with the rear opening portion 6b of the ink containing tube 6, and a small-diameter rear cylinder portion 21 which is formed on a rear end of the front cylinder portion 20 through a rear wall 20b in a coaxial shape so as to be connected thereto, where the inside of the front cylinder portion 20 forms a pressurizing chamber 22. In the rear cylinder portion 21, from a rear aperture 21a to the front aperture 21b, the front end portion 17a of the pressing member 17 is pushed and inserted so as to communicate with the outside air.
The front end portion 17a of the pressing member 17 is pressed into the front aperture 21b of the rear cylinder portion 21 so as to tightly stopper the front aperture 21b, by the pressing operation accompanied with the frontward movement of the pressing member 17. With such a configuration, it is possible to maintain the airtight state of the pressurizing chamber 22.
FIG. 4 is a sectional view in an initial pressurized state. Likewise, FIG. 5 is an enlarged sectional view of a main section in the initial pressurized state. FIG. 6 is an enlarged perspective view illustrating the half-section of pressurizing member in a compressive deformation state.
In the non-pressurized state illustrated in FIGS. 1 to 3, as shown in FIGS. 4 to 6, when the knock section 11 performs a pressing operation toward the front in a half pressed state against the bias force of the compression spring 12, the knock bar 13 cooperates with the operation and moves frontward, and then the rotor 15 is rotated by a half circle through the cam mechanism portion 14. By the half rotation of the rotor 15, the pressing member 17 moves frontward, and the front end portion 17a is pressed into the state pushed into the front aperture 21b, whereby the inside of the pressurizing chamber 22 is maintained in the airtight state.
Subsequently, by a further pressing operation of the pressing member 17, the rear cylinder portion 21 bends and deforms the rear end section of the front cylinder portion 20 toward the front of the inside and the rear wall 20b toward the rear, while compressing the pressurizing chamber 22 so as to push them into the front cylinder portion 20. In this case, the compressed air is forcibly pumped into the rear opening portion 6b of the ink containing tube 6, and thus pressurizing the inside of the rear opening portion 6b thereof.
At this time, in the half pressed state of the knock section 11, since the spring force of the compression spring 12 is set to be smaller than the spring force of the compression spring 9 biasing the pen refill unit 4 toward the rear, the pen refill unit 4 is not moved frontward by the pressing force of the knock section 11. For this reason, the pen tip 7 is still contained in the front member 3.
FIG. 7 is a sectional view in a maximum pressurized state. FIG. 8 is a sectional view in a pressurized state at the time of using the pen.
In the initial pressurizing state illustrated in FIGS. 4 to 6, as shown in FIG. 7, when the knock section 11 pressed frontward by using a force stronger than the spring force of the compression spring 9, the knock bar 13 moves frontward and the rotor 15 is further rotated by the cam mechanism portion 14 in cooperation with the pressing operation. By driving the rotor 15, the pressing member 17 is compressed toward the inside of the pressurizing chamber 22 in the airtight state, the air in the pressurizing chamber 22 is forcibly pumped into the inside of the rear opening portion 6b of the ink containing tube 6, and thus the rear opening portion 6b of the ink containing tube 6 is pressurized more. In this case, since the pushing force of the knock section 11 is greater than the spring force of the compression spring 9 biasing the pen refill unit 4 to the rear, the pen refill unit 4 moves frontward, and the pen tip 7 is protruded from the inside of the front member 3 in the front end section 2a of the barrel 2 toward the outside thereof.
Subsequently, when releasing the pressing operation of the knock section 11, as shown in FIG. 8, only the knock bar 13 is returned rearward to a desired locking position by the bias force of the compression spring 12, the rotor 15 is locked at its driving position at the moment. Therefore, since the pen tip 7 maintains the protruded state and the pressing member 17 is in the state of pressing the elastic cylindrical member 19 of the pressurizing member 18, the pressurizing chamber 22 maintains the pressurizing state.
With such a configuration, since the inside of the ink containing tube 6 is continuously maintained in the pressurizing state at the time of using the pen, and it is thus possible to write even in the state that the pen's front section is inclined upward.
After using the pen, when the knock bar 13 is activated again by pushing the knock section 11 toward the front against the bias force of the compression spring 12, the locking state of the rotor 15 with respect to the cam mechanism portion 14 is released, and the knock bar 13 is returned rearward by the bias force of the compression spring 12. At this time, the rotor 15 moves rearward in company with the pressing member 17, and the rotor 15 is returned to original position illustrated in FIGS. 1 and 2, by the bias force of the compression spring 9. Simultaneously, the elastic cylindrical member 19 of the pressurizing member 18 is returned from the compressed state to the elongated state, and the pressurizing chamber 22 in the ink containing tube 6 and in the front cylinder portion 20 of the elastic cylindrical member 19 becomes the airing state by being separated from the front aperture 21b of the rear cylinder portion 21 of the front end portion 17a in company with the return toward the rear of the pressing member 17. As a result, the pressurizing state in the ink containing tube 6 is released.
With such a configuration, it is possible to obtain the pressurized pen having excellent feeling of using the pen by allowing an easy knocking operation with small force.
The above description of preferred embodiments has been given by way of example. From the disclosure given, those skilled in the art will not only understand the present invention and the attendant advantages, but will also find apparent various changes and modifications to the structures disclosed. It is sought, therefore, to cover all such changes and modifications as fall within the spirit and scope of the invention, as defined by the appended claims, and equivalents thereof.
BRIEF DESCRIPTION OF REFERENCE NUMERALS
1: KNOCK-TYPE BALL-POINT PEN
2: BARREL
2A: FRONT END SECTION
2B: REAR END SECTION
3: FRONT MEMBER
3A: APERTURE SECTION
4: PEN REFILL UNIT
5: INK (MEDIUM)
6: INK CONTAINING TUBE
6A: FRONT END PORTION
6B: REAR OPENING PORTION
7: PEN TIP
8: HOLDER
9: COMPRESSION SPRING
10: KNOCK MECHANISM
11: KNOCK SECTION
12: COMPRESSION SPRING
13: KNOCK BAR
14: CAM MECHANISM PORTION
15: ROTOR
16: PRESS PUMP MECHANISM
17: PRESSING MEMBER
17A: FRONT END PORTION
18: PRESSURIZING MEMBER
19: ELASTIC CYLINDRICAL MEMBER
20: FRONT CYLINDER PORTION
20A: FRONT END
20B: REAR WALL
21: REAR CYLINDER PORTION
21A: REAR APERTURE
21 B: FRONT APERTURE
22: PRESSURIZING CHAMBER
Patent Application
20080019761
