WO2005100045A1

WO2005100045A1 - Front-knock type ballpen

Info

Publication number: WO2005100045A1
Application number: PCT/KR2004/001833
Authority: WO
Inventors: Bon-Chun Koo
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-04-16
Filing date: 2004-07-22
Publication date: 2005-10-27
Anticipated expiration: 2006-10-16
Also published as: KR200356696Y1

Abstract

A front-knock type ball-point pen. A knock cap is received in the front cap, formed with coupling protrusions, and defined with a writing tip extending and retractingn part and engagement grooves. A return spring is placed in the knock cap to bias the knock cap in a direction in which the writing tip extending and retracting part projects out of a front cap. A knock cam is formed with prominences which are engaged in the engagement grooves or on the other end surface of the nkock cap and has a saw-toothed edge. A rotation cam is installed through the knock cam, defined with coupling grooves in which the coupling protrusions of the knock cap are coupled, and formed with lockers which are engagned on knock-engagement projections formed on a circumferential inner surface of a barrel. A knock spring is positioned at a rear end of the refill.

Description

Front- nock type ballpen

Technical Field The present invention relates to a front-knoc type ball-point pen, and more particularly, to a front-knock type ball-point pen used when studying or conducting paperwork, which is constructed in a way such that a writing tip of a refill comprising an ink container-tube can be extended out of and retracted into a barrel by pressing a front portion of the ball-point pen without the need of changing a gripping state of the fingers using the ball-point pen, thereby providing user convenience, and such that a user can enjoy the feeling of a slightly springy writing tip.

Background Art In a conventional ball-point pen, a writing tip is extended out of and retracted into a barrel by pressing a push button which emerges from a rear end of the barrel.

Concretely speaking, due to the fact that a knock part is provided in the barrel, when the push button is pressed, the knock part is moved upward or downward to extend or retract the writing tip out of or into the barrel. Thus, the push button must be pressed when using the ball-point pen and pressed again to retract the writing tip into the barrel after use. For this reason, inconvenience is caused in that a gripping state of the fingers using the ball-point pen needs to be changed between during and after use. Also, the conventional ball-point pen is not free from shortcomings in that it is often difficult to properly press the push button when it is necessary to take a memo or notes in an urgent basis. Referring to Korean Utility Model Publication No. 1981- 1229, there is disclosed a device for extending and retracting a writing tip of a ball-point pen out of and into a barrel. In this device, a front cap is coupled to a front end of the barrel, and knock-engagement projections are formed on a circumferential inner surface of the front cap. A knock cam and a rotation cam are provided in the front cap to be moved upward and downward through the knock-engagement projections. When the rotation cam is pressed, the knock cam is knocked on the knock-engagement projections. In this way, by pressing a front portion of the rotation cam, it is possible to extend and retract the writing tip of the ballpoint pen out of and into the front cap, that is, barrel. However, the device suffers from defects in that, since the rotation cam must be pressed to a position of a front end of the front cap to extend the writing tip out of the front cap, when the rotation cam is pressed like this, ink on the writing tip is likely to be unintentionally conveyed to paper.

Disclosure of the Invention Therefore, the present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a front-knock type ball-point pen, wherein a writing tip of a refill can be extended out of and retracted into a barrel only by slightly pressing a front portion of the ball-point pen while it is possible to prevent ink on the writing tip from being unintentionally conveyed to paper, and a user is permitted to enjoy a comfortable writing feel with the aid of a cushioned writing action of the ballpoint pen. In order to achieve the above object, according to the present invention, there is provided a front-knock type ball-

^■ point pen having both ends to which a front cap and a rear cap are respectively coupled, and including a barrel in which a knock cam and a rotation cam are provided so that, every time the knock cam is pressed, lockers of the rotation cam are repeatedly engaged on and disengaged from knock- engagement projections formed on a circumferential inner surface of the barrel, to reciprocate a refill in a lengthwise direction of the barrel to thereby extend and retract a writing tip of the refill out of and into the barrel, the pen comprising: a knock cap received in the front cap, formed on a circumferential inner surface thereof with a pair of rectangular coupling protrusions, and defined at one end thereof with a writing tip extending and retracting part and at the other end thereof with a plurality of engagement grooves; a return spring placed in the knock cap to bias the knock cap in a direction in which the writing tip extending and retracting part of the knock cap projects out of the front cap; a knock cam formed on a circumferential outer surface thereof with engagement prominences which are engaged in the engagement grooves or on the other end surface of the knock cap when the knock cam is knocked, and having a saw- toothed edge at the other end thereof; a rotation cam installed through the knock cam, defined at one end thereof with coupling grooves in which the coupling protrusions of the knock cap are coupled when the rotation cam is knocked, and formed at the other end thereof with the lockers which are engaged on the knock-engagement projections formed on the circumferential inner surface of the barrel; and a knock spring positioned at a rear end of the refill to bias the refill in one direction.

Brief Description of the Drawings The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: FIG. 1 is an exploded perspective view illustrating a front-knock type ball-point pen in accordance with an embodiment of the present invention; FIG. 2 is a cross-sectional view illustrating an assembled state of the front-knock type ball-point pen according to the embodiment of the present invention; and FIGs. 3 through 5 are partial cross-sectional views illustrating operations of the front-knock type ball-point pen according to the embodiment of the present invention.

Best Mode for Carrying Out the Invention Reference will now be made in greater detail to a preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts . FIG. 1 is an exploded perspective view illustrating a front-knock type ball-point pen in accordance with an embodiment of the present invention; and FIG. 2 is a cross- sectional view illustrating an assembled state of the front- knock type ball-point pen according to the embodiment of the present invention. A front-knock type ball-point pen in accordance with an embodiment of the present invention includes a barrel 10 which comprises an elongated cylindrical body. Knock- engagement projections 1,1 are formed on a circumferential inner surface of the barrel 10, and a knock cam 20 and a rotation cam 30 are installed in the barrel 10. A front cap 60 and a rear cap 90 are coupled to both ends, respectively, of the barrel 10. Knocking operations of the knock-engagement projections 11, knock cam 20 and rotation cam 30 are well known in the art . The knock-engagement projections 11 are formed on the circumferential inner surface adjacent to a front end of the barrel 10. Inclined surfaces 12 are formed at rear ends of the knock-engagement projections 11. The front cap 60 and the rear cap 90 are coupled to both ends on a circumferential outer surface of the barrel 10. It is preferred that the front cap 60 and the rear cap 90 are threadedly coupled to both ends of the barrel 10. The knocking operations are implemented in a manner such that the knock cam 20 and the rotation cam 30 are engaged between the knock-engagement projections 11 to be reciprocated or rotated. The knock cam 20 is inserted into and from a rear end of the barrel 10 and has a hollow configuration. A plurality of engagement prominences 26 are formed on a circumferential outer surface of and at a predetermined separation from a front end of the knock cam 20. A plurality of movement projections 21 are formed on the circumferential outer surface at a rear end of the knock cam 20. The rear end of the knock cam 20 defines a saw-toothed edge 23 which is to be meshed with lockers 33 of the rotation cam 30. In this embodiment, three engagement prominences 26 of the knock cam 20 are formed to be spaced apart one from another by an angle of 120°. As the knock cam 20 is reciprocated, the engagement prominences 26 are repeatedly engaged into and disengaged from engagement grooves 56 or a rear end surface 59 of a knock cap 50. The rotation cam 30 is inserted through the knock cam 20 in a manner such that a front end of the rotation cam 30 emerges out of the front end of the knock cam 20. The rotation cam 30 also has a hollow configuration. A pair of coupling grooves 34 are defined at the front end of the rotation cam 30, and the lockers 33 are projectedly formed on a circumferential outer surface at a rear end of the rotation cam 30. Like the engagement prominences 26, the lockers 33 of the rotation cam 30 are formed to be spaced apart one from another by an angle of 120°. By this fact, as the lockers 33 are meshed with the saw-toothed edge 23 and the knock cam 20 is reciprocated, the lockers 33 are rotated by a predetermined angle due to the presence of the inclined surfaces 12 of the knock-engagement projections 11, and coupling protrusions 54 of the knock cap 50 are respectively coupled into the coupling grooves 34 to allow the knock cap 50 to be rotated integrally with the rotation cam 30. Before the rotation cam 30 is assembled in the knock cap 50, a return spring 40 is placed in the knock cap 50. The return spring 40 is inserted toward the front end of the barrel 10 in a manner such that a rear end of the return spring 40 is seated on a front end surface of the rotation cam 30 and a front end of the return spring 40 is seated on a circumferential inner surface of the knock cap 50, to bias the knock cap 50 in a direction in which a writing tip extending and retracting part 55 of the knock cap 50 projects out of the front cap 60. The knock cap 50 is inserted into and from the front end of the barrel 10. A pair of elongate coupling protrusions 54 are formed on the circumferential inner surface of the knock cap 50. The engagement grooves 56 are defined at a rear end of the knock cap 50 to be spaced apart one from another by an angle of 120°. A front end of the knock cap 50 forms the writing tip extending and retracting part 55 which can project out of the front cap 60. The coupling protrusions 54 of the knock cap 50 are respectively coupled into the coupling grooves 34 of the rotation cam 30. The pair of coupling protrusions 54 are formed in a manner such that the return spring 40 can be inserted between the coupling protrusions 54 and rear ends of the coupling protrusions 54 are not brought into contact with a front end surface of the knock arm 20. If the engagement prominences 26 are engaged into the engagement grooves 56, the knock cam 20 and the rotation cam 30 are moved forward to reach front ends of the knock- engagement projections 11. If the engagement prominences 26 are disengaged from the engagement grooves 56 and engaged on the rear end surface 59 of the knock cap 50, the lockers 33 of the rotation cam 30 and the saw-toothed edge 23 of the knock cam 20 are positioned on the inclined surfaces 12 of the knock-engagement projections 11 to effect a knocked state. In this state, by slightly pressing the knock cap 50, the knocked state can be released. The front cap 60 is locked to the front end of the barrel 10. A circumferential inner surface of the front cap 60 is formed in a manner such that the knock cap 50 can be received in the front cap 60. It is preferred that a thread is formed on the circumferential inner surface at a rear end of the front cap 60 to allow coupling of the front cap 60 to the barrel 10. After the knock cam 20, rotation cam 30, knock cap 50 and the front cap 60 are assembled to the barrel 10, a refill 70 comprising an ink container-tube is inserted into and from the rear end of the barrel 10. The refill 70 is inserted through the rotation cam 30, and is formed at a middle portion thereof with a first protuberance 77a which is brought into contact with a rear end surface of the rotation cam 30. The refill 70 is further formed adjacent to a rear end thereof with a second protuberance 77b which functions to support a knock spring 80. The rear end of the refill 70 is inserted into a support part 97 of the rear cap 90. The knock spring 80 is fitted around and from the rear end of the refill 70 in a manner such that a front end thereof is seated against the second protuberance 77b and the rear end thereof is seated against the support part 97 of the rear cap 90, to forwardly bias the refill 70. The rear cap 90 is coupled to the rear end of the barrel 10, and formed on an inner surface thereof with the support part 97 in which the rear end of the refill 70 is movably inserted. It is preferred that a thread is formed on a circumferential inner surface at a front end of the rear cap 90 to allow coupling of the rear cap 90 to the barrel 10. A clip 98 is formed on a circumferential outer surface of the rear cap 90 to improve portability of the ball-point pen. Hereafter, operations of the front-knock type ballpoint pen according to the present invention, constructed as mentioned above, will be described in detail. Referring to FIGs. 3 through 5, FIG. 3 is a cross- sectional view illustrating main component elements in a state wherein a writing tip of the refill 70 is extended out of the writing tip extending and retracting part 55 of the knock cap 50. As the movement projections 21 of the knock cam 20 and the lockers 33 of the rotation cam 30 are moved and positioned at the front ends of the knock-engagement projections 11 which are formed on the circumferential inner surface of the barrel 10, the engagement prominences 26 of the knock cam 20 are engaged into the engagement grooves 56 of the knock cap 50 to extend the writing tip of refill 70 out of the writing tip extending and retracting part 55. At this time, the writing tip extending and retracting part 55 of the knock cap 50 also projects out of the front cap 60 by the elastic force of the return spring 40. FIG. 4 is a cross-sectional view illustrating the main component elements in a state wherein the writing tip extending and retracting part 55 of the knock cap 50 and the writing tip of the refill 70 are retracted into the front cap 60. In order to retract the writing tip into the front cap 60, the writing tip extending and retracting part 55 of the knock cap 50 and the writing tip of the refill 70 are retracted into the front cap 60. In this state, the knock cam 20 and the rotation cam 30 are moved upward by the knock cap 50. FIG. 5 is a cross-sectional view illustrating the main component elements in a state wherein the lockers 33 of the rotation cam 30 are knocked to retract the writing tip into the writing tip extending and retracting part 55, and the writing tip extending and retracting part 55 of the knock cap 50 projects out of the front cap 60 to protect the writing tip of the refill 70. The writing tip extending and retracting part 55 of the knock cap 50 projects out of the front cap 60 by the elastic force of the return spring 40. The rotation cam 30 is rotated in a predetermined direction by the lockers 33 and the inclined surfaces 12 of the barrel 10, and the knock cam 20 is also rotated in the same direction as the rotation cam 30. By this fact, the engagement prominences 26 are positioned on the rear end surface 59 of the knock cap 50. Moreover, as the first protuberance 77a of the refill 70 is brought into contact with the rear end surface of the rotation cam 30 to knock the rotation cam 30, the writing tip of the refill 70 is retracted into the writing tip extending and retracting part 55. If the rotation cam 30 is released from the knocked state, the writing tip of the refill 70 is extended out of the writing tip extending and retracting part 55. When it is necessary to extend the writing tip of the refill 70 to use the ball-point pen (see FIG. 3) , by slightly pressing the writing tip extending and retracting part 55, the engagement prominences 26 move the knock cam 20 and the rotation cam 30 upward, and then, as the rotation cam 30 is rotated by the predetermined angle by the inclined surfaces 12, the knocked state is released. Thereupon, the engagement prominences 26 are engaged into the engagement grooves 56, respectively, whereby the knock cam 20 and the rotation cam 30 are moved downward to extend the writing tip of the refill 70 out of the writing tip extending and retracting part 55. A person skilled in the art will readily recognize that the front-knock type ball-point pen according to the present invention can be applied to a various kinds of ball-point pens and modified in its construction in a diversity of ways to apply the present invention to the various kinds of ball- point pens .

Industrial Applicability As apparent from the above descriptions, the front- knock type ball-point pen according to the present invention provides advantages in that a writing tip of a refill can be quickly extended out of a barrel only by slightly pressing a front portion of the ball-point pen in a ready-to-write state. Therefore, user convenience is provided since ink on the writing tip is prevented from being unintentionally conveyed to surrounding objects. Also, because a predetermined degree of elasticity is always applied to the refill, the ball-point pen is convenient to use even in a jolting vehicle or during walking with the aid of a cushioned writing action of the ball-point pen. Further, by the cushioned writing action of the ball-point pen, a user can enjoy a comfortable writing feel even when taking notes for an extended period of time. While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment and the drawings, but, on the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims .

Claims

Claims 1. A front-knock type ball-point pen having both ends to which a front cap and a rear cap are respectively coupled, and including a barrel in which a knock cam and a rotation cam are provided so that, every time when the knock cam is pressed, lockers of the rotation cam are repeatedly engaged on and disengaged from knock-engagement projections formed on a circumferential inner surface of the barrel, to reciprocate a refill in a lengthwise direction of the barrel to thereby extend and retract a writing tip of the refill out of and into the barrel, the pen comprising: a knock cap received in the front cap, formed on a circumferential inner surface thereof with a pair of rectangular coupling protrusions, and defined at one end thereof with a writing tip extending and retracting part and at the other end thereof with a plurality of engagement grooves; a return spring placed in the knock cap to bias the knock cap in a direction in which the writing tip extending and retracting part of the knock cap projects out of the front cap; a knock cam formed on a circumferential outer surface thereof with engagement prominences which are engaged in the engagement grooves or on the other end surface of the knock cap when the knock cam is knocked, and having a saw-toothed edge at the other end thereof; a rotation cam installed through the knock cam, defined at one end thereof with coupling grooves in which the coupling protrusions of the knock cap are coupled when the rotation cam is knocked, and formed at the other end thereof with the lockers which are engaged on the knock-engagement projections formed on the circumferential inner surface of the barrel; and a knock spring positioned at a rear end of the refill to bias the refill in one direction.

2. The front-knock type ball-point pen according to claim 1, wherein the engagement prominences of the knock cam and the corresponding engagement grooves of the knock cap are formed to be spaced apart one from another by an angle of 120°.

3. The front-knock type ball-point pen according to claim 1, wherein the refill is formed with protuberances for supporting the return spring and the knock spring, respectively.

4. The front-knock type ball-point pen according to claim 1, wherein the rear cap is formed on a circumferential outer surface thereof with a clip.