JPH0986093A - Compass pencil lead holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for holding a pen core of a compass wherein the lead is hardly broken and the lead can be fed out lightly. SOLUTION: A back barrel 4 to be attached to a leg rod of a compass has a slit 30 and has a guide hole 9 therein. To the back barrel 4, an outer cylinder 10 is attached. At a back end of a chuck 22 housed in the outer cylinder 10, a pressing cylinder 19 is provided. In the pressing cylinder 19, a guide 8 to be inserted into the guide hole 9 is formed. In the outer periphery of the outer cylinder 10, a knock ring 25 is fitted movably in the axial direction. A connecting piece 28 arranged on the knock ring 25 is engaged with the pressing cylinder 19 through the slit 30. When the knock ring 25 is moved, the chuck 22 moves being guided by the guide 8 and the knock ring 25 so as to feed out a lead 6 from the outer cylinder 10.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a compass core,
The present invention relates to a lead holding device which is detachably attached to a leg rod of the compass and used.

[0002]

2. Description of the Related Art A variety of sharp pencil type lead holding devices which are detachably attached to a compass and used. These lead holding devices basically use a mechanism similar to that of a sharp pencil and are configured to feed the lead by rotating operation or knocking operation, but a knock type lead holding device is used. The compass has a drawback in that the pressing force from the leg rod is directly transmitted to the lead chuck during use, and the lead chuck is loosened and the lead is immersed.

Various proposals have been made to eliminate such drawbacks. For example, an outer cylinder is attached to the leg rod of the compass, a chuck, a lead tank, etc. are stored in the outer rod so that the pressing force from the leg rod is not directly transmitted to the lead chuck.
Further, it is known that when the lead is fed out, the operating piece attached to the lead tank is knocked through a groove formed in the outer cylinder to feed the lead. However, in such a configuration, a smooth knocking operation cannot be performed unless the operation piece is accurately attached laterally to the center axis of the lead tank, etc. Since the structure is pushed down from one side, the core tank and the chuck are less likely to move straight when knocked, and an oblique force acts on the core to easily break the core, and in addition, it can be operated with one fingertip. Since one piece has to be operated, a strong force is required, manufacturing is troublesome, and there are various problems such that each device must be prepared according to the size of the compass.

[0004]

According to the present invention, in a compass lead holding device as described above, the lead can be drawn out by a light knock operation,
At this time, it is possible to provide a compass lead holding device that prevents the chuck from accurately moving straight and does not cause core breakage, can be easily manufactured, and can easily cope with large and small compasses. To aim.

[0005]

A core holding device for a compass according to the present invention comprises:
A rear shaft attached to the leg rod of the compass, an outer cylinder attached to the rear shaft, and a lead-out mechanism portion housed in the outer cylinder,
The knock ring is fitted to the outer circumference of the outer cylinder, and the knock ring is provided so as to be movable in the axial direction of the outer cylinder, and the chuck of the lead-out mechanism is moved by the movement of the knock ring. A device in which a knock ring connecting piece is connected to a pressing cylinder provided at the rear of the chuck through a slit formed in an outer cylinder or the like, and more preferably, the pressing cylinder of the pressing cylinder is provided so as to guide the movement of the chuck in the axial direction more correctly. There is provided a device characterized in that a guide shaft formed at a rear portion is fitted into a guide hole of the rear shaft, thereby achieving the above object.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Since the outer cylinder is attached to the rear shaft attached to the compass, the pressing force acting on the leg rod of the compass is not directly transmitted to the lead feeding mechanism portion housed inside the outer cylinder. Therefore, the core does not sink while the compass is in use, and when the knock ring is moved in the axial direction along the outer cylinder, the chuck moves linearly guided by the knock ring and the guide shaft, and the core cannot be forced. The force can be applied and the core can be fed out in a stable state.

In the drawings showing one embodiment of the present invention, a lead holding device is a rear shaft removably attached by a fastening screw (3) provided on a leg rod (2) of a compass (1) as is well known. (4), the rear shaft (4) is formed with a bifurcated attachment piece (5) at its rear end, and an insertion hole (7) for the core (6) is formed in the center thereof. A guide hole (9) for slidably inserting the guide shaft (8) is provided following the insertion hole (7). The rear axle is prepared with a long total length and a short total length according to the size of the compass.

An outer cylinder (10) is attached to the front portion of the rear shaft (4). In the figure, a rear shaft (4) is formed with an insertion portion (11) having a male screw, and the insertion portion (11) is formed at the rear end of an outer cylinder (10) and has an attachment portion (12) having a female screw. Although it is inserted into and screwed in, the insertion part and the mounting part, the male screw and the female screw, etc. may be provided on the members on the opposite sides, respectively, and instead of screwing, press fitting and other known various connections A structure can be adopted or an appropriate configuration can be adopted. The outer cylinder (10) has a lead-out mechanism (13) housed inside, and a cap (15) integrally formed with a pipe (14) at the tip for projecting the lead (6). However, the base portion and the tubular body may be formed separately and then connected. In the base (15),
As is well known, an elastic piece (16) for holding the core (6) and a stepped portion (18) with which the clamp ring (17) of the chuck abuts are formed.

The lead-out mechanism (13) includes an inner cylinder and a pressing cylinder (19) having a guide shaft (8) having a core insertion hole (7) inserted in the guide hole (9) at the rear portion thereof. A chuck (22) with a clamp ring (17) having a proximal end fixed to the pressing cylinder (19) through a through hole (21) formed at the tip of (20), the pressing cylinder (19) and an inner cylinder (20). ) Is provided with a spring (23) provided between the tips. The inner cylinder (20) is inscribed in the outer cylinder (10), and the front end of the inner cylinder (20) is in contact with the stepped portion (24) formed in the outer cylinder (10). The tip of the insertion part (11) of (4) contacts and the outer cylinder
It is fixed in (10).

A knock ring (25) is fitted on the outer circumference of the outer cylinder (10) so as to be guided by the outer circumference and movable in the axial direction. The knock ring (25) is formed in a short cylindrical shape, and the rear end of the knock ring (25) is pressed so as to define holes (26), (26) through which the insertion part (11) of the rear shaft (4) is inserted. Shoulder of tube (19)
A connecting piece (28) that engages with (27) is formed, and the connecting piece (2
A through hole (29) through which the guide shaft (8) of the pressing cylinder (19) is inserted is provided at the center of 8). The guide shaft (8)
May be formed to have a short length so as to simply engage with the through hole (29), and an appropriate protrusion or the like for engaging the pressing cylinder with the knock ring may be provided without providing the guide shaft. Alternatively, the knock ring and the pressing cylinder may be connected. The width of the connecting piece (28) is such a width that it can be inserted into the slit (30) formed in the insertion portion (11) of the rear shaft (4). In the slit (30), the connecting piece (28) is the shoulder portion (27) of the pressing cylinder (19).
It may be formed on the outer cylinder (10) depending on the position where it is engaged with, or may be formed from the rear shaft (4) to the outer cylinder (10).

The rear shaft (4) constructed as described above,
The knock ring (25), the lead-out mechanism (13) and the outer cylinder (10) are
As shown in FIG. 2 (B), the outer cylinder (10) is sequentially assembled from the rear end, and finally the rear shaft (4) is fitted into the knock ring holes (26) and (26).
It can be easily assembled by screwing to the mounting portion (12) of the outer cylinder (10) through the. In this state, the chuck (22) is centered by the guide shaft (8) and the knock ring (25), so if the knock ring (25) is pinched with a fingertip and moved in the tip direction, a very stable state is obtained. You can move straight and move the lead (6). The rear axle (4) may have a length corresponding to the size of the compass.

[0012]

Since the present invention is constructed as described above and the lead feeding mechanism is housed in the outer cylinder, the lead does not sink during use of the compass, and the chuck can be moved by the knock ring. Therefore, even when the compass is in use, it can be moved lightly by pinching and operating the knock ring with two fingertips. Moreover, the chuck is guided by the guide shaft and the knock ring. Since it moves straight correctly and no excessive force is applied to the core, it is possible to prevent core breakage, etc. Also, the structure is simple and easy to assemble, and the length of the rear shaft depends on the size of the compass. It can be made economically by simply changing the.

[Brief description of drawings]

FIG. 1 is a front view of a usage state.

FIG. 2 is an enlarged view showing a state in which the compass is removed,
(A) is a sectional view and (B) is an exploded perspective view.

[Explanation of symbols]

 4 Rear shaft 6 core 8 Guide shaft 9 Guide hole 10 Outer cylinder 13 Core feeding mechanism 19 Pressing cylinder 20 Inner cylinder 22 Chuck 25 Knock ring 28 Connecting piece 30 Slit

Claims (2)

[Claims] 1. A rear shaft attached to a compass leg rod,
A core feeding mechanism part having a pressing cylinder inserted in the rear shaft at the rear part and having a proximal end of the chuck fixed through an inner cylinder through the pressing cylinder, and the above-mentioned core feeding mechanism part housed inside, and the core projects at the tip. An outer cylinder having a mounting portion for mounting the rear shaft at the rear end and a knock ring fitted to the outer periphery of the outer cylinder so as to be movable in the axial direction, and a connecting piece is attached to the knock ring. A core holding device for a compass, wherein the connecting piece is connected to the pressing cylinder through a slit formed in the rear shaft and / or the outer cylinder, and the pressing cylinder is moved by the knock ring to extend the core. 2. The core holding device for a compass according to claim 1, wherein the rear shaft has a guide hole in the center thereof, and the pressing cylinder has a guide shaft inserted into the guide hole at a rear portion thereof.