JPH0617585Y2 - Telescopic shear pencil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a telescopic mechanical pencil whose shaft length is extendable and retractable and whose core is retractable inside the shaft when the shaft length is shortened.

(Prior Art) A writing instrument requires a required axial length for convenience in writing, but when not in use, a shorter one is more convenient in consideration of storage in a pocket when carrying. Therefore, it is desired to make the axial length flexible.

By the way, in the case of mechanical pencils, generally, a small-diameter core protection pipe is projected at the tip and the core protrudes from the tip, and the core may be pierced into clothes when it is stored in a pocket, or may be broken by falling or the like. Therefore, it is desired that the core can be retracted inside the shaft while the shaft length is shortened.

Therefore, conventionally, as disclosed in Japanese Utility Model Laid-Open No. 59-164786, a writing instrument has been devised in which the shaft length is expandable and contractable, and the core can be retracted into the shaft while the shaft length is shortened.

However, since the writing instrument of this conventional example adopts a means of pressing a spring-loaded pressing stopper piece against the inner surface of the grip cylinder as a means for fixing the state where the shaft is extended or contracted, the fixed state is unstable. Also, there is a hole in the rear end face when the shaft is extended, so the external appearance is not good.Furthermore, when the shaft is extended, the knock part goes inside the gripping cylinder and cannot be knocked, so the core cannot be knocked. There are problems such as being unable to extend.

(Problems to be solved by the invention) Therefore, the present invention allows the shaft length to be expanded and contracted, which is convenient for carrying, etc. Further, the core can be retracted inside the shaft with the shaft length shortened. Fixation is stable when the shaft length is extended or contracted, and in addition, there is no hole on the rear end face when the shaft length is extended, and the external appearance is good, and knocks when the same axis length is extended. It is possible to provide a telescopic mechanical pencil that can be extended and the core can be extended.

(Means for Solving the Problems) The telescopic mechanical pencil of the present invention devised to achieve the above-mentioned object is provided with the chuck 9 and the front case 1 accommodating the core case 16 connected to the rear thereof with respect to the front shaft 1. The shaft 23 is mounted movably in the axial direction, the eraser holder 34 having the rear end fitted with the knock cover 33 is housed inside the rear shaft 23, and the eraser holder 34 is biased rearward by the knock spring 35. The knock cover 33 is always in a protruding state from the rear end opening of the rear shaft 23, and the longitudinal groove portion 13 axially long on the side surface of the lead case 16 and the lateral groove portion 1 bent substantially vertically at the front and rear end positions thereof.
4 and 14 'are provided, and the eraser holder 34 is provided with an inner surface projection 29 which is movably fitted in the guide groove 15. The rear shaft 23 is retracted with respect to the front shaft 1 to extend the axial length. In this state, the inner surface projection 29 of the eraser holder 34 is fitted into the rear end lateral groove portion 14 ′ of the guide groove 15 of the lead case 16 and locked, whereby the knock cover 3
3 allows knocking of the core by the chuck 9, and the rear projection 23 is advanced with respect to the front spindle 1 to shorten the axial length so that the inner surface protrusion 29 of the eraser holder 34 guides the core case 16. It is characterized in that the knock cover 33 is knocked by fitting and locking the front end lateral groove portion 14 in the groove 15 so that the chuck 9 can be advanced and opened.

(Embodiment) The drawings show an embodiment of the present invention, in which the joining cylinder 2 is press-fitted and fixed to the inner surface of the front end of the front shaft 1, and the press-fit ring 3 is fixed to a required position behind the front end 1. A pressing ring 4 is fixed to the portion, a retaining ring 5 is fixed to the front end of the inner hole of the joining cylinder 2, and a chuck case 7 having a tapered surface 6 on the inner surface is housed. A ball chuck 9 having a ball 8 interposed between it and the taper surface 6 is housed in a state of being biased rearward by a chuck spring 10, and at the rear position of the ball chuck 9 inside the front shaft 1, a pressing wall is formed on the inner surface of the front end. 11, a flange 12 is provided on the outer surface near the front end, and an axial longitudinal groove portion 13 and a lateral groove portion 14 bent substantially vertically at the front and rear end positions are provided on the outer surface of the rear half portion as shown in FIG. , 14 'with a guide groove 15 consisting of The spring 16 is arranged, and a return spring 17 is interposed between the collar portion 12 of the lead case 16 and the rear end of the joining tube 2 to urge the lead case 16 to the rear side. A mouthpiece 18 is screwed onto the front end of the joining cylinder 2 protruding from the portion, and a holding chuck 20 and a core protection pipe 21 integrally fixed inside the mouthpiece 18 via a holder 19 are movable in the axial direction. And a pressing ring 22 for preventing the holder 19 from coming out backward is fixed, while the pressing ring 4 of the front shaft 1 is provided on the outer peripheral portion of the rear end of the front shaft 1 so that an appropriate frictional force is generated on the inner surface. The rear shaft 23 is mounted so as to be movable in the axial direction in a state of being in contact with the rear shaft 23. At the front end of the rear shaft 23, there is a decorative ring 24 capable of colliding with the pressing ring 4 fixed to the outer surface of the rear end of the front shaft 1. Fix the receiving ring 25 to the inner surface part slightly rearward from the center. Screw tube 26 at the rear end portion
A crown 28 is screwed into the screw tube 26 while sandwiching the mounting portion of the clip 27 in the screw tube 26, and the rear shaft 23 has a protrusion 29 on the inner surface of the front end and a collar portion on the outer surface near the rear end. Further, an eraser stopper 32 having an eraser 31 held therein is fitted to the rear end tubular portion of the rear end portion 30 and an eraser holder 34 formed by attaching a knock cover 33 to the outer peripheral portion is axially movable. In addition, the front end inner surface projection 29 is fitted into the guide groove 15 of the core case 16 so as not to rotate in the circumferential direction, and a knock spring 35 is interposed between the outer surface flange portion 30 and the receiving ring 25 of the rear shaft 23. When the rear shaft 23 is mounted and biased rearward, the stroke of the rear shaft 23 relative to the front shaft 1 relative to the distance between the lateral groove portions 14 and 14 ′ at the front and rear ends of the guide groove 15 in the core case 16 (first Leader shaft in the state of Fig. 1 The distance between the rear end and the receiving ring 25) in which the configured set somewhat longer. When the knock cover 33 is not pressed, the eraser holder 34 keeps the flange portion 30 in contact with the threaded pipe 26 by the knock spring 35, and is interlocked with the rear shaft 23 when the rear shaft 23 moves axially relative to the front shaft 1. To do. When the rear shaft 23 is retracted with respect to the front shaft 1 as shown in FIG.
2 is brought into contact with the press-fitting ring 3 of the front shaft 1, but in this state, a slight gap is set between the pressing wall 11 of the lead case 16 and the rear end of the ball chuck 9.

(Operation) The operation will be described based on the above embodiment. First, FIG. 1 shows a state in which the rear shaft 23 retracts from the front shaft 1 and the shaft length extends. At this time, the inner surface projection 29 of the eraser holder 34 is fitted in the rear end lateral groove portion 14 ′ of the guide groove 15 of the core case 16. When the knock cover 33 is pushed forward in this state, the eraser holder 34 advances, the inner surface projection 29 thereof pushes the front wall of the lateral groove portion 14 ', the core case 16 moves forward, and the pushing wall 11 at the front end portion of the ball moves. When the ball chuck 9 comes into contact with the rear end of the chuck 9 and the axis of the ball chuck 9 shifts, the lead is fed out, and writing becomes possible. When the writing is completed, first, the rear shaft 23 is slightly rotated with respect to the front shaft 1 to cause the protrusion 29 of the eraser holder 34 to escape from the lateral groove portion 14 'of the core case 16 and be positioned at the rear end of the vertical groove portion 13, and then The rear shaft 23 is pressed forward with respect to the shaft 1 to advance the protrusion 29 of the eraser holder 34 along the vertical groove portion 13, and when the front end is reached, the rear shaft 23 is rotated again to move the protrusion 29 to the horizontal groove portion 14 at the front end.
Fit in. Since the rear shaft 23 can be further advanced to some extent with respect to the front shaft 1, when the rear shaft 23 is pushed further forward until the rear end edge of the front shaft 1 contacts the receiving ring 25 of the rear shaft 23, the lead case 16 erases the rubber. The pressing wall 11 is pushed forward by the holder 34 and its pressing wall 11 comes into contact with the rear end of the ball chuck 9 to move the ball chuck 9 forward to open the lead gripping portion of the ball chuck 9 and free the lead. Therefore, the lead 36 can be freely retracted, and the lead protection pipe 21 protruding forward of the mouthpiece 18
When the rear is pressed, the holding chuck 20, the holder 19, and the lead protection pipe 21 are integrally retracted to move the lead protection pipe 2
1 and the core 36 are immersed in the base 18. This state is shown in FIG.

(Effects of the Invention) The present invention is as described above. When writing, the axial length has the required length and is easy to use, and when not in use, the axial length is shortened so that it can be carried in a pocket or the like. Is convenient, and when the shaft length is shortened, the core can be retracted inside the mouthpiece and problems such as piercing into clothes and breaking due to falling are eliminated, and the shaft length is extended or contracted. Since the inner surface protrusions of the eraser holder are fitted and locked in the lateral grooves provided at the front and rear ends of the guide groove of the core case, the fixed state is stable and the knock cover pushes against the knock spring even when the shaft length is extended. Since it is projected from the rear shaft rear end opening, there is no hole in the rear end face and the appearance is good, and the knock cover also protrudes from the rear shaft rear end opening when the shaft length is extended and knocking is possible. So let out the core It has the effect of being convenient.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a side view showing a cross section of the upper half of the shaft with its axial length extended, and FIG. 2 shows the upper half of the shaft with its axial length shortened. A side view in section and FIG. 3 are partially developed plan views of the lead case. 1 ... Front shaft, 2 ... Joining cylinder, 3 ... Press-fit ring, 4 ...
Pressing ring, 5 ... Stop ring, 6 ... Tapered surface, 7
...... Chuck case, 8 ... Ball, 9 ... Ball chuck, 10 ... Chuck spring, 11 ... Pressing wall,
12 ... Collar part, 13 ... Vertical groove part, 14, 14 '... Horizontal groove part, 15 ... Guide groove, 16 ... Core case, 17 ... Return spring, 18 ... Base, 19 ... Holder,
20 ... Holding chuck, 21 ... Lead protection pipe, 22 ...
… Presser ring, 23 …… Rear shaft, 24 …… Decorative ring, 2
5 ... Receiving ring, 26 ... Screw tube, 27 ... Crip, 28 ... Crown, 29 ... Protrusion, 30 ... Collar part, 31
…… Eraser, 32 …… Eraser stopper, 33 …… Knock cover, 34 …… Eraser holder, 35 …… Knock spring, 36 …… Core.

Claims (1)

[Scope of utility model registration request] 1. An eraser holder 34 in which a rear shaft 23 is axially movably mounted on a front shaft 1 containing a chuck 9 and a lead case 16 connected to the rear thereof, and a knock cover 33 is fitted to the rear end. Is housed inside the rear shaft 23, and the eraser holder 34 is urged rearward by a knock spring 35 so that the knock cover 33 is always projected from the rear end opening of the rear shaft 23. Longitudinal groove 1 long in the direction
3 and lateral groove portions 14 which are bent substantially vertically at the front and rear end positions thereof
4'and a guide groove 15 composed of 4'and an inner surface projection 29 movably fitted in the guide groove 15 is provided on the eraser holder 34, and the rear shaft 23 is retracted from the front shaft 1 to extend the axial length. Inner surface protrusion 29 of the eraser holder 34
The rear end lateral groove portion 1 in the guide groove 15 of the lead case 16.
In the state where the knock cover 33 is knocked by being fitted into 4'and locked to allow the lead out by the chuck 9, and the rear shaft 23 is advanced with respect to the front shaft 1 to shorten the shaft length. The inner surface protrusion 29 of the eraser holder 34 is fitted and locked in the front end lateral groove portion 14 of the guide groove 15 of the lead case 16 so that the knock cover 33 can be knocked and the chuck 9 can be advanced and released. Telescopic mechanical pencil.