JP3187418B2 - Pencil with lead mechanism - Google Patents

Abstract

A mechanical lead pencil having the capability of feeding different diameter leads. A first collet (21) is disposed in the pencil barrel (12) for feeding the lead (20) and a second collet (25) is located at the barrel open end for retaining the lead (20) during use of the pencil. An elastomeric disc (35) is provided between the two collets (21, 25), having a variable diameter opening (38) at the center thereof for frictionally engaging the lead (20) and preventing its release when the two collets (21, 25) are in the open position.

Description

The present invention relates to a continuous feed mechanism for a pencil, and more particularly, to a continuous feed mechanism for a pencil that can use leads having a plurality of diameters.

Heretofore, various types of pencils with a center feeding mechanism that are satisfactory to consumers are commercially available, and a number of centering mechanisms have been proposed for these pencils.

In recent developments in the market for pencils having a center-feed mechanism, the introduction of pencils having a continuous center-feed mechanism including a cartridge containing a plurality of leads has been performed, and a number of leads have been introduced into the pencil through the feed mechanism. Is done.

However, in the market, the pencil with the lead mechanism is limited to a single lead diameter by the structure of the lead mechanism.
The core typically used for this type of pencil has a diameter of
There are two types, 0.5 millimeter and 0.7 millimeter.
It is not fed through the front opening of a small diameter pencil barrel limited to support a 0.5 millimeter core. Similarly, a 0.5 mm lead, when fed through the front opening of a pencil barrel manufactured to use a 0.7 mm lead, will protrude from the pencil opening by an enlarged opening. Are improperly supported and may break.

Occasionally, consumers need to use a pencil with a 0.5 millimeter core for use in activities typically in the technical or accounting field, while they prefer a 0.7 millimeter core for writing purposes. Therefore, the user needs to have at least two pencils that the user is satisfied with in order to obtain a suitable acceptable line quality.

Thus, as is evident from the foregoing, current market refill vendors have stopped selling various sized cores to accommodate the various feed mechanisms found in these commonly used pencils. There is a need to. In addition, the owner may be confused when deciding on the size of the lead required by a particular pencil when buying a refill, and may notice that he bought the wrong size lead when placing the lead in the pencil. There is.
Accordingly, there is a need for a continuous pencil with a center feed mechanism having a feed mechanism for receiving cores of multiple diameters.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a pencil having a center feed mechanism of the type in which the feed mechanism can accept leads of multiple diameters.

It is another object of the present invention to provide a pencil having a feed mechanism for receiving a plurality of diameter leads manufactured without radial departure from a mass produced continuous lead pencil.

Yet another object of the present invention is to provide a pencil having a continuous feed mechanism that is simple to manufacture and economical to manufacture by known manufacturing methods.

The foregoing and other objects, which will become apparent as the description proceeds, are achieved by providing a pencil having a feed mechanism of the type using a replaceable wick, the pencil having an opening formed in the front end toward which the wick is directed. A cylindrical elongated barrel having A first gripping device releasably engaging the wick and moving the wick toward the front end of the barrel comprises:
A second gripping device, located at a point remote from the forward end of the barrel and for releasably engaging the wick, is located at the opening at the forward end of the barrel.

A device that frictionally engages the wick is provided on the first and second wick grippers to maintain the wick positioned within the barrel when the wick is released by the first and second wick grippers. It is located between them.

The device for frictionally engaging the wick has a disk of resilient material having a circular opening formed in the center thereof for receiving the wick by frictional engagement and disposed radially outward from the circular opening. And has a plurality of slits extending through the thickness of the disc to allow great flexibility of the circular opening formed in the center of the disc.

More specifically, a first gripping device for releasably engaging a wick comprises a collet having a plurality of collet members biased outwardly from a wick held in a pencil barrel; And a collet collar for retaining a collet member that engages the wick when in a rear position. A second gripping device for releasably engaging the wick has a collet having a plurality of collet fingers, the collet fingers extending partially beyond the front end of the barrel;
It is biased outward from the barrel axis. The front end opening or tip of the barrel has an inner wall that slopes forward and outward at a sharp angle to the axis of the barrel and collet fingers, and the barrel and collet fingers have a barrel opening with an outer surface that engages the sloped wall. Deployed, whereby during forward and backward movement, the collet is held in sliding engagement with the inner ramp by the biasing force of the outer side of the collet finger.

The foregoing and other features of the invention will be described in more detail with reference to the preferred embodiments and accompanying drawings.

FIG. 1 is a front sectional view showing details of a mechanical lead pencil using the present invention.

FIG. 2 is a front sectional view similar to FIG. 1 showing details of the pencil of FIG. 1 during operation.

FIG. 3 is a front sectional view showing one element of the structure of FIGS. 1 and 2 enlarged for clarity.

Referring now to the drawings, and in particular to FIGS. 1 and 2, there is shown a pencil 10 with a feed mechanism of the type having a barrel 12, the barrel 12 having an external thread 16 on the rear outer surface.
Has 14 The barrel 12 has a bush 17 secured to its inner surface and a stationary sleeve 18 that is pushed into the bush 17 so that the bush 17 and sleeve 18 are secured against axial rotation or movement within the barrel 12. . The bush 17 has an inner front surface for engaging a male thread 16 provided on the barrel tip 14 so that the barrel tip 14 can be removed when assembling various components located at the front end of the barrel 12. A female screw 19 is provided.

The device for releasably engaging the wick 20 is provided in the form of three place collets 21 having a collet member 22, only two of which are shown in FIGS. . Collet 21 is aftly applied within barrel 12 by a spring (not shown) or other means having sufficient force to retract collet member 22 into cylindrical collet collar 24 movable within barrel tip 14. It is being rushed.

As best shown in FIG. 1, the collet 21 urged rearward causes the outer sloped surface of the collet member 22 to create a wedge action between the collet collar 24 and the core 20 to allow the collet collar and collet member to move The combination provides the core 20 with a substantial gripping force.

Referring to FIG. 1, the second collet 25 has a barrel tip.
Located at the front end of 14 and partially extends beyond a front opening 26 through which wick 20 extends for writing purposes. Collet 25 has three collet fingers 28 (only two of which are shown) that are biased outward by the spring action of the fingers. A face 27 inclined forward and outward is formed in the opening 26 of the barrel tip 14, and a collet finger 28 has an outer surface 29 inclined inward and rearward corresponding to the face 27, as shown in FIG. An elliptical retainer ring 30 formed of a plastic, metal or other substantially rigid material is engaged therein when the collet 25 is in the most rearward position as shown in FIG. Along with the rearward extension of the spring collet finger 28 provided, it is located within the barrel tip 14. Retaining ring 30 is collet finger 28
A spring 32 is disposed between the retainer ring 30 and the surface 33 of the barrel tip 14 and biases the collet 25 rearward to the position shown in FIG.

Referring to FIGS. 1-3, a circular disc of elastic material
35 is provided between the bearing surface 36 and the rear surface of the retainer ring 30.

3, the disk 35 has a circular opening 38 formed therein and a plurality of slits 39 extending radially outward from the opening 38 and extending through the thickness of the disk.
And The material of the disc is rubber or other elastic material, the thickness of which is such that the segments of the disc between the slits 39 can flex to accommodate a plurality of different diameter objects in the opening 38. That's it. The means for frictionally engaging the wick is shown here as a disc 35, but the structure adjacent the circular opening 38 is integrally molded to provide sufficient flexibility to accommodate a core of one or more diameters. It will be appreciated that the finger or other means may be provided.

In operation, the pencil with the feed mechanism is placed in the barrel 12 as shown in FIG. 1 while the appropriate amount of lead extends beyond the tip of the collet 25 forming the foremost position of the pencil 10. The core 20 is used for writing purposes. As can be seen in FIG. 1, the wick 20 is securely gripped by the collet member 22 and is frictionally retained within the disc 35, and the collet fingers 28 serve to stabilize the wick against radial movement during writing. Is gripped by The collets 21 and 25 can be opened to accept multiple diameter cores, but hold the core and maintain its support during writing. In a similar manner, a disc 35 formed of an elastic material and provided with a slit 39 can receive a core of multiple diameters and provides a frictional gripping force on the core when received in the opening 38. be able to. Wick 20 may be a wick fed into a pencil or one of a number of wicks housed in a dispensing cartridge, as will be appreciated by those skilled in the art.

Referring now to FIG. 2, when it is desired to move the wick 20 forward through the barrel 12, the collet 21 moves forward toward an opening 26 in the barrel tip 14. The forward movement of the collet 21 can be achieved in a manner well known in the field of pencils, for example, by using the rear of the pencil, i.e. Achieved by applying pressure by hand. As described above, the collet member 22 and the collet collar 24 move the core 20, the collet member 22 by the forward movement of the collet 21.
And, the collet collar 24 is moved around the barrel 12 so as to be fixed around the core. Rearward stop surface 40 is barrel 12
Extends radially inward within the opening of the collet collar
The movement of the collet members 22 is stopped by the contact of the stop surface with the stop surface 24, and the movement of the collet members 22 releases them from the collet collar 24 and releases them to the spring.
Release the wick 20 as shown in FIG.

At the front edge of the barrel tip 14 having a collet 25 secured in gripping relationship with the wick 20, the movement of the wick is a collet finger 28.
Is moved forward against the biasing force of the spring 32, and in doing so, the collet finger 28 is released by the spring action of the spring finger and the wick is released as shown in FIG.

In the above-described operation of the wick, at the point of movement of the wick 20 that has reached its foremost position, both the collet member 22 and the collet finger 28 are disengaged from the wick 20. However, this core is held in frictional engagement with disc 35, and collet 21 and collet 25 are held in place while returning to their rearmost position as shown in FIG. Not as free as falling from.

As can be seen in the structure described above, the collet 21, the disc 35 and the collet 25 perform a distinct function in the operation of the pencil 10 with feed mechanism. The collet 21 effectively grips the wick 20 and moves the wick forward to extend beyond the opening 26 in the barrel tip 14, while the collet 25 serves to grip the wick 20 during writing. Disc 35 effectively holds core 20 in the barrel at the operating point where the core is released by both collets 21 and 25. However,
Each element, collet 21, collet 25 and disc 35
Can perform certain actions as described when multiple diameter leads are used in a pencil. Thus, the pencil 10 provides the user with a variable writing instrument that is not limited to either a 0.5 mm or 0.7 mm core as in prior art writing instruments.

Obviously, changes and modifications may be made within the spirit and scope of the invention, but only by the claims.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B43K 21/16, 21/22 B43K 24/00, 24/08

Claims (5)

(57) [Claims] 1. An elongated cylindrical barrel (12, 14) for accommodating a plurality of diameter cores each having a substantially uniform diameter in a replaceable manner, and through which a core 20 can pass from a rear end to a front end. ) And a first gripping device (2) provided at a position spaced rearward from the front end in the barrel.
1) and a second gripping device (2
5) wherein the first gripping device is operable to releasably engage the wick (20) and move the wick toward the forward end. A pencil with a center feed mechanism operable to releasably engage with a lead (20) at a front end, wherein a first holding device and a second holding device in a barrel (12, 14) are provided. An elastic disk (35) having a central opening (38) is disposed concentrically with the barrel and the core (20), the disk being formed of an elastic material and extending from the central opening (38) to the outer periphery of the disk. A plurality of slits (39) extending radially outwardly, wherein the disc frictionally engages a core (20) passing through the central opening, and wherein the first and second gripping devices are Operable to hold the wick when open , Pencil with lead function. 2. A first gripping device which engages with a core comprises: a collet (21) having a plurality of collet members urged outward from an axis of the barrel (12); The pencil with a center feeding function according to claim 1, wherein the pencil is a collet collar (24) that holds the collet member in an engaged state with the core (20) when the collet member is at a rear position in the barrel (12). 3. A second gripping device releasably engaging the wick is a collet (25) having a plurality of collet fingers (28), wherein a portion of the collet fingers (28) has a forward end of the barrel. 3. The lead-in pencil according to claim 1 or 2, wherein the pencil extends beyond and is biased outward from the axis of the barrel. 4. A center feeding function according to claim 3, wherein a spring (32) for urging the second collet (25) rearward in the barrel is provided in the barrel (12, 14). With pencil. 5. The barrel front end opening (26) has a barrel (12,1).
4) having an inner wall inclined forward and outward at an acute angle with respect to the axis of 4), wherein the collet fingers (28) are provided on the inclined wall (2).
7) having an outer surface (29) for engaging the collet (25) during forward and rearward movement of said collet.
The pencil with a center-feeding function according to claim 3 or 4, wherein the pencil is held in sliding engagement with the inner inclined wall (27) by an outward biasing force of the collet finger (28).