BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a conventional push button pen while a refill retracts;
FIG. 2 is a perspective view of the embodiment in FIG. 1 while the refill extends;
FIG. 3 is an explosive view of the embodiment in FIG. 1;
FIG. 4 is a lateral cross sectional view of the embodiment in FIG. 1;
FIG. 5 is an explosive view of an embodiment in accordance with the present invention;
FIG. 6 is a lateral cross sectional view of the embodiment in accordance with the present invention while the refill retracts;
FIG. 7 is a partial enlarged view of the embodiment in FIG. 6;
FIG. 8 is a lateral cross sectional view of the embodiment in accordance with the present invention while the refill extends;
FIG. 9 is partial enlarged view of the embodiment in FIG. 8;
FIG. 10 is a lateral cross sectional view of another embodiment in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFFERED EMBODIMENT
Refer from FIG. 5 to FIG. 9, a push button pen 2 is composed of an outer pen tube 20, a button 30, an inner tube 40, a refill 50 and a compression spring 60. The style of the present invention is similar to conventional push button pen 1 shown in FIG. 1 & FIG. 2. A plurality of guiding slots on the circumference 21 and a central hole 22 are disposed inside a tail end of the outer pen tube 20. The button 30 is a tube threaded with a hollow tube 31 that inserts through the front end of the outer pen tube 20 and the central hole 22.
Moreover, a ratchet 32 with diameter a bit larger than the diameter of the hollow tube 31 is disposed on circumference of the front end of the hollow tube 31. A flange 33 with diameter smaller than that of the hollow tube is arranged on inner surface of the ratchet 32. On outer circumferences of front end and rear end of an inner sleeve 40, respectively mount a stopping ring 41, 42 while a load ring 43 slidable on the inner sleeve 40 is arranged between the two stopping rings 41, 42. The load ring 43 is made from metal such as cooper or iron with certain weight. Furthermore, a shaft 44 extending outwards with a ratchet 45 outside is set on rear end of the inner sleeve 40. The ratchet 45 can be integrated with the shaft 44 or be an independent element assembled with the shaft 44, as shown in FIG. 5.
The ratchet 45 matches the ratchet 32 on the button 30. The shaft 44 inserts through the flange 33 on inner surface of the front end of the hollow tube 31, threaded with a sliding ring 46 so that the shaft 44 and the sliding ring 46 slide freely inside the hollow tube 31 without falling off from the front end thereof. In other words, when the shaft 44 moves forwards along with the inner sleeve 40, the sliding ring 46 firstly stops by the flange 33 of the hollow tube 31. Then the hollow tube 31 is forced to move forward together with the button 30. The refill 50 is mounted inside the inner sleeve 40 and the front end of the refill 50 is loaded into the compression spring 60. After the outer pen tube 20 being assembled with a front half tube 23, one end of the compression spring 60 presses against an inner surface of the front half tube 23 while the other end elastically presses against the refill 50 so as to make the refill 50 along with the inner sleeve 40 and the ratchet 45 all against the ratchet 32 for providing the button 30 restoring spring force during knocking on process.
In usage, by pressing the button 30 repeatedly, the refill 50 of the push button pen 2 according to the present invention is retractable. The pressing operation of the present invention is similar to that of general push button pen 1. Between the button 30 and the inner sleeve 40, the two corresponding ratchets 32, 45 moves elastically by spring force of the compression spring 60 and in combination with the guiding slots 21 on rear end of the outer pen tube 20, a nib 52 of the refill 50 extends out or retracts into a head 24 of the front half tube 23 of the outer pen tube 20 as shown in FIG. 1 & FIG. 2. As to the interaction between the ratchets 32, 45, with the guiding slots 21 inside the read end of the outer pen tube 20, it is similar to the way mentioned above.
By shaking forwards, the refill 50 of the push button pen 2 according to the present invention extends or retracts. No matter the refill 50 retracted (in FIG. 1) or extended (in FIG. 2), put the button 30 downwards so as to make the load ring 43 slides downwards to the rear stopping ring 42 and then shake the push button pen 2 forwards. The shake here means that user's hand moves a certain distance quickly and then stops immediately. By shaking force, the load ring 43 slides forwards rapidly from the rear stopping ring 42 to the stopping ring 41 of the inner sleeve 40. Due to inertia and momentum of the load ring 43, the inner sleeve 40 along with the refill 50 and the hollow tube 31 along with the button 30 are driven to slide forward. Thus each time of shaking has the same effect as pressing the button 30. The nib 52 of the refill 50 extends out or retracts into a head 24 of the front half tube 23, as shown in FIG. 1 & FIG. 2. Therefore, the push button pen 2 can also be used in shaking way.
Refer to FIG. 10, the button of the push button pen 2 according to the present invention can be removed. A cap 24 is fixed on rear end of the outer pen tube 20 so that the present invention can only be used as a shake pen. This depends on requirement of clients.