JPS5914999A - Propelling pencil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention relates to a mechanical pencil, and more specifically, the lead advances automatically by pressure on the rear button (knock type).
It's about mechanical pencils.

Mechanical pencils of the above models, especially with an extra-fine lead (0.5 m)
Mechanical pencils provided for m) are susceptible to irregularities in the lead advancing device, on the one hand, due to the rigidity of the advancing device and the rigidity of the lead in the position of use, and on the other hand, due to the guidance generally acting on the threaded part. Due to its coaxial arrangement, it has the disadvantage that the core breaks relatively frequently. therefore,
An object of the present invention is to provide a mechanical pencil that avoids the above-mentioned disadvantages.

The subject of the invention achieves the above objects, comprising a body formed by a tubular part and a head fixed to the front end thereof, and a core advancement device mounted within the body,
and the two supports to which the core advancer is connected to the body slide axially between the pedestals and are such that an actual elastic action maintains the core advancer in the advanced position. It exists in mechanical pencils featuring the following.

An embodiment of the present invention will be described below based on the accompanying drawings.

As shown, the mechanical pencil includes a body formed by a tubular portion 1 containing a lead advancement device 2 and having a pointed head 6 at the front end of the key.

The core advancement device 2 consists of a central tube 4 sliding longitudinally and provided at its rear end with a push button 5 extending rearwardly outside the tubular body 1. A ring 6 is secured to the forward end of the central tube, the ring 6 being supported on one end of a main spring 7, the other end of which is slidably mounted within the head 6 and is mounted therein. a socket 9 in which the main spring 7 is arranged;
It is in contact with the shoulder 8 which exhibits.

The core advancement device includes a gripper 10 with jaws 11, 11' which are fixed in the ring 6 by their rear ends and which are clamped into the closed position by means of a cone 12. (see figure).

Advancement of the wick (not shown) is initiated by pressure on the pushbutton 5, which, against the action of the main spring 70, moves forward (on the left in the figure) of the entire central tube 4-ring 6-grip 10. , so that the front part of the jaw 11 . 11 ′ is moved into the cavity 16 . This movement thus advances the wick, which is clamped between the jaws 11.degree. 11', across the rubber retaining ring 14 and across the tip of the head 6 in the outlet passage 15. When the pressure on the pushbutton 5 is released, the central tube 4-ring 6-
The entire gripping body 10 returns to the rear under the action of the main spring, and during this backward movement the jaws 11 then located in the cavity 16
, 11' can be opened and moved without retracting the core until the jaws 11, 11' are tightened back into the cone 12 when they again engage the core. The device is then ready for a new forward movement, if necessary.

Furthermore, a brake spring 16 disposed around the forward end of the central tube 4 is supported forwardly at the rearward end of the socket 9 and rearwardly at the forward end of the knurled male member 17;
The thread is provided with a skirt portion 18 extending inside the tubular member 1 with the head 6 facing rearward. As shown in the accompanying drawings, the knurled male member 17 is connected to the brake spring 16.
It is made to adjust. With respect to the lower part of the figure, the spring 16 is in its normal use position, and when in the upper part of the figure, the knurled male member 17 is screwed in so that the spring 16 is fully compressed and thus of the fixed core. It doesn't move at all.

In this way, when the brake spring 16 is in its normal position of use, the pressure on the core is applied slightly towards the rear, against the action of the spring 16, when the user is writing, for example. 1
0-Socket 9-Central tube 4-Push button 5 There is a tendency to press the whole. Therefore, the mechanical pencil according to the invention has a braking effect during use, which presents a comfortable writing flexibility to the user and considerably reduces the risk of breakage when shocks are applied to the lead. Furthermore, by means of the knurled male member 17, the force of the brake spring 16 can be adjusted by the force that the user applies to the lead when writing or sketching.

Finally, in the illustrated embodiment, the front portion of the core advancement device is slidably mounted and is comprised of a single piece, namely the head 6.
The skirt portion 18 is guided axially within and extends itself rearwardly, which tends to considerably reduce coaxiality errors ensuring high operational reliability.

[Brief explanation of the drawing]

The drawing shows an embodiment of the mechanical pencil according to the invention, the lower half of the drawing showing the braking device in the normal use position and the upper half showing the braking device in the blocking position. In the figure, 1 is a tubular part, 2 is a core advancement device, 6 is a pointed head, 4 is a central tube, 6 is a ring, 7 is a main spring, 8 is a shoulder, 9 is a socket, 10 is a gripping body, 11.11' is a jaw part, 17 is a knurled male member, and 18 is a skirt part. Agent Patent Attorney Kiyotaka Sasaki

Claims (1)

Claims: (1) A mechanical pencil comprising a body formed by a tubular portion and a head secured to the front end thereof, and a lead advancement device mounted within the body, The two supports to which the core advancer is connected to the body slide axially between the pedestals, and in fact have a resilient action to maintain the core advancer in the advanced position. Characteristic mechanical pencil. (2) A forward portion of the core advancement device is axially mounted and guided and slides within a skirt portion of the head and itself extending into the tubular portion of the body. Mechanical pencil according to item 1 of the range. (8) A mechanical pencil according to claim 1 or 2, characterized in that the elastic action is adjustable. (4) A mechanical pencil according to any one of claims 1 to 6, characterized in that the front and rear supports have bases connected to the head. (5) The mechanical pencil according to any one of claims 1 to 4, wherein the rear support is adjustable in the axial direction. (6) The rear support is configured by a mechanism in which the base is screwed onto a screw thread having an inner wall from a skirt portion extending toward the head toward the rear. Mechanical pencil as described. (7) The mechanical pencil according to claim 6, wherein the mechanism is a knurled male member having a portion that can be accessed from the outside of the skirt portion. (8) The support for the main spring of the core advancing device includes a sleeve that slides on the central tube of the core advancing device and serves as a pedestal.
Mechanical pencil as described. (9) The mechanical pencil according to claim 8, wherein the elastic action is exerted between the front surface of the base of the rear support and the rear surface of the sleeve of the lead advancing device. 00) Claims 1 to 9, characterized in that the elastic action is exerted by one spring.
Mechanical pencil as described.