JP2003251995A - Drafting instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drafting instrument such as a compass or a divider with such advantages that a needle cover can be smoothly moved by one hand to a lower dead spot position for covering a needle and an upper dead spot position for exposing a needle and firmly retained by engagement at both lower dead spot and upper dead spot and further, that even when the instrument accidentally falls onto a floor or the like, the needle is certainly prevented from springing out under improved safety measures and handling procedures. <P>SOLUTION: A retaining part 7 which retains the needle cover 6 in a freely sliding manner and also in a freely rocking manner in a needle leg 2 direction, is provided between the needle leg 2 with the needle 1 and the needle cover 6 wrapping the needle 1. In addition, an engagement part 8 for the lower dead spot which becomes engaged in a freely engaging/ disengaging manner when the first half part side of the rocking center of the needle cover 6 is rocked under pressure by advancing the needle cover 6 sliding to the lower dead spot position where the needle 1 is covered and an engagement part 9 for the upper dead spot which becomes engaged in a freely engaging/disengaging manner when the needle cover 6 is moved backward to the upper dead spot position where the needle 1 is exposed by rocking the second half part side of the rocking center, are provided between the needle leg 2 and the needle cover 6. Thus the safety measures and handling procedures of the drafting instrument are improved. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drafting tool having a needle such as a compass or a divider, for example, when the compass is not used, the central needle protruding from the lower end of the leg is covered up to erroneously stab a hand. The present invention relates to a needle cover that eliminates the danger of needle sticks, etc. and ensures safety in handling.

[0002]

2. Description of the Related Art Conventionally, in drafting tools such as compasses, various measures have been taken to prevent accidents caused by needles. For example, a compass equipped with a safety needle cover is known from Japanese Utility Model Laid-Open No. 3-62897.
The compass disclosed in Japanese Utility Model Laid-Open No. 3-62897 is vertically slidable around the central needle of a projecting leg having a central needle in parallel with the direction of the central needle by artificial force. The needle cover is equipped with a needle cover, and the inner surface of the needle cover and the surface of the needle leg have a disengagement prevention function that prevents the needle cover from falling off, a bottom dead center position that covers the center needle of the needle cover, and a top dead point that exposes the center needle. A long groove and a small protrusion that perform a guiding function with respect to a point position are provided respectively. That is, when not in use, the small protrusion slides to the bottom dead center position of the needle cover where it engages with the lower end of the long groove, thereby covering the central needle and preventing accidents such as needle sticks. When used, the small protrusion is slid to the top dead center position of the needle cover where the small protrusion engages with the upper end of the long groove, so that the central needle projects to the outside from the slot at the lower end of the needle cover.

[0003]

However, in the above-described conventional compass, the needle cover is held at the bottom dead center position for covering the center needle and the top dead center position for projecting the center needle. This is due to the frictional resistance between the inner surface of the needle cover and the outer surface of the needle leg, which has a substantially U-shaped cross section for holding the leg. Therefore, conventionally, it is essential to increase the frictional resistance due to the surface friction of the needle cover with respect to the needle leg, so that the movement of the needle cover is slow. Therefore, when sliding the needle cover, firmly grasp the needle cover so as to sandwich it, and unless you firmly grasp the needle leg with the other hand, slide the needle cover to its bottom dead center or top dead center position. A problem occurs in terms of handleability, especially for children such as elementary school children (school children), it becomes difficult to move the needle cover, and the needle that is distracted only by moving the needle cover protrudes. Could be stabbed in your finger or palm.

Further, in the conventional compass, in addition to holding the needle cover at the bottom dead center and top dead center positions due to surface friction, the operation of the needle cover for covering and exposing the needle is performed as described above. Since it only slides up and down in parallel with the above, it is essential that the front end of the needle cover (needle tip covering part) has a protruding / withdrawing port for projecting or retracting the needle that opens in a substantially U shape in bottom view. is there. Therefore, when the compass is accidentally dropped on the floor, the needle cover moves due to the impact, and the needle that should have been covered in the accommodated state protrudes from the slot, and you can pick it up without noticing that the needle is protruding. There was a risk of accidentally sticking when doing so, and it was necessary to take safety measures in handling.

The present invention has been made in view of such conventional circumstances, and the object thereof is to smoothly and with one hand hold the needle cover at the bottom dead center position where the needle is covered and at the top dead center position where the needle is exposed. It can be easily moved, and the needle cover can be firmly locked and held at both bottom dead center and top dead center, and the needle will surely pop out even if it is dropped on the floor etc. It is to provide drafting tools such as compasses and dividers that have improved safety measures and handleability so that they can be prevented.

[0006]

In order to achieve the object, the present invention provides a drafting tool having a needle, such as a compass or a divider, which has a needle leg having the needle and is swingable in the direction of the needle leg. Between the needle cover that is slidable in the vertical direction, the bottom dead center position of the needle cover that covers the needle, and
That is, there is provided a locking portion that alternately and disengageably locks at two points above and below the top dead center position where the needle cover is exposed.

Further, the present invention provides a drafting tool having a needle, such as a compass or a divider, between a needle leg having the needle and a needle cover having a substantially U-shaped cross section for covering the needle. A holding portion for holding the needle cover slidably in the vertical direction and swingable in the needle leg direction, and further, between the needle leg and the needle cover, a needle is provided at a bottom dead center position for covering the needle. The bottom dead center locking part that engages and disengages freely when the cover is slid forward and the front half of the swing center of the needle cover is swung, and the rear half of the swing center is pressed. A top dead center locking portion that locks detachably when the needle cover is slid and retracted at a top dead center position where the needle is exposed by swinging.

The bottom dead center and top dead center engaging portions are formed of a convex portion and a concave portion that are fitted to each other, one of which is on the needle cover side and the other is on the needle leg side of the needle cover. By providing the position at the bottom dead center position and the top dead center position, the needle cover is securely attached at the bottom dead center position where the needle is covered and the top dead center position where the needle is exposed, with the convex lock and the concave lock locked. That is to make it possible to hold.

Further, the needle cover is formed of a material having elasticity and appropriate rigidity into a substantially U-shaped cross section, and has a bottom dead center and a top dead center on both sides on the front half side of the swing center. By providing both dead part locking parts, and by providing a slit on the front half side that divides both side parts from the lower end to the left and right,
The certainty of the locking force of both the locking portions and the stability (improvement of durability) for a long period of time are ensured.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific example of the embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a compass as an example of a drawing tool having a needle according to the present invention. A companion leg 2 having a needle 1, a writing leg 3, an opening / closing pivot portion 4 of the legs 2 and 3, and a center of an upper surface of the pivot portion 4. In the well-known configuration including the knob 5 provided, a needle cover 6 is attached to the lower end side of the needle leg 2 from which the needle 1 projects so as to be swingable and vertically slidable. By the way,
Examples of the compass include a sharp type including a sharp leg 3-1 on the writing leg 3 as illustrated, a pencil type including a pencil holder for attaching a pencil, and a lead type including a lead holder for attaching a pencil lead.

As shown in FIG. 2, the cross-sectional shape of the lower end side of the needle leg 2 in the vertical slide range of the needle cover 6 from the lower end where the needle 1 projects is shown in FIG. 2 as a wide portion 2-1 and a narrow portion 2-2. And a holding portion 7 for holding the needle cover 6 slidably up and down and swingably in the needle leg 2 direction, is formed on both side surfaces of the upper portion of the wide portion 2-1. Locking portions 8 and 9 for the slide bottom dead center and the top dead center of the needle cover 6 are provided on both sides of the lower end of the portion 2-2.

The needle cover 6 covers the needle 1 by both swinging in the direction of the needle leg 2 and sliding vertically.
A synthetic resin that exposes the needle 1 (see FIGS. 4A and 4C) and has excellent elasticity (restoring force) and appropriate rigidity (wear resistance and durable strength that maintains elastic force). Using a molding material such as a material, for example, a thermoplastic resin material such as polypropylene or polycarbonate, having a needle tip coating portion 6-1 at the front end (lower end), which is formed into a U-shape with a predetermined cross-section I am doing it. Further, by forming the thickness of both side portions 6-2 on the front half side of the needle cover 6 to which the needle tip coating portion 6-1 is continuously provided to be thicker inward, the needle leg 2 is formed inside the front end side. The narrow groove portion 10 that fits into the narrow portion 2-2 and slides with the inner dimension corresponding to the width of the narrow portion 2-2 is provided at two positions above and below the inner surfaces of both grooves of the narrow groove portion 10. Locking parts 8 for bottom dead center and top dead center,
9 is provided.

Further, the side view shape of the open end edges of the both side portions 6-2 of the needle cover 6 is approximately from the front end side continuously provided to the needle tip covering portion 6-1 toward the rear end side in the longitudinal direction. After being formed into a V-shape, the curved edge 6- is formed by being continuously provided in a substantially curved shape toward the rear end of the upper side portion 6-3 and located behind the central portion of the needle cover 6 in the longitudinal direction. The needle cover 6 is held on the inner surface of both side portions 6-2 at the corner portion where 21 parts and the V-shaped edge portion 6-20 are continuously connected so as to be vertically slidable and swingable in the needle leg 2 direction. The holding part 7 is provided.

Reference numeral 11 in the drawing denotes a slit provided from the front end of the needle cover 6 having the needle tip covering portion 6-1 to the front half portion along the width center of the upper side portion 6-3, as shown in FIG. slit
By providing 11, the concave portions 8-1, 9-1 and the convex portions 8-2, 9 (to be described later) of the locking portions 8 and 9 for the bottom dead center and the top dead center of the needle cover 6 are provided.
-It secures the locking force that can be engaged and disengaged with -2 and the stability (improvement of durability) over a long period of time. Also, 12 in the figure
Is a slip stopper provided on the upper side 6-3 of the needle cover 6,
Along the fingertips (abdomen) of the thumb along the slip stopper 11, the front half and the rear half of the needle cover 6 having the swing center P as a fulcrum are pressed and swung in the direction of the needle leg 2 or vertically slid. The needle cover 6 to be moved can be smoothly operated (see FIG. 4).

The holding portion 7 is slidable in the vertical direction in a state in which the needle cover 6 cannot be removed from the needle leg 2 and the needle leg 2 is provided.
And a long groove 7-1 provided in the rear portion of the wide portion 2-1 of the needle leg 2 in the vertical slide range of the needle cover 6, and the long groove 7-1. With the outer diameter and height corresponding to the groove width and depth of the needle cover 6, the protrusions 7-2 projecting on the above-mentioned inner surface of the side portions 6-2 between the front half and the rear half of the needle cover 6 are formed. The needle cover is configured so that the front half part and the rear half part of the needle cover can be pressed and oscillated in the direction of the needle leg 2 around the protrusion 7-2. That is, the protrusion 7 is formed at the lower end of the long groove 7-1.
After the needle cover 6 is slid forward to the bottom dead center position where -2 is locked, the needle cover 6 with the protrusion 7-2 as the swing center P
By pressing and swinging the front half of the needle leg 2, the needle 1 protruding from the lower end of the needle leg 2 can be covered, and in this state, the latter half of the swing center P of the needle cover 6 is pressed and swings. By moving the needle cover 6, the needle cover 6 can be slid and retracted to the top dead center position where the needle 1 is exposed and the needle is completely exposed.

The bottom dead center locking portion 8 pushes and swings the front half of the swing center P of the needle cover 6 after sliding the needle cover 6 forward to the bottom dead center position where the needle 1 is covered. When they are made to fit, they are engaged with each other and locked to firmly lock and hold the needle cover that covers the needle. The locking portion 8 includes a concave portion 8-1 provided on both side surfaces of the front end of the narrow portion 2-2 of the needle leg 2 and a convex portion 8-1 provided on both inner surfaces of the rear end of the narrow groove portion 10 of the needle cover 6. 2 and, after the needle cover is slid forward from the top dead center position, the front half portion (upper side portion 6-3 front end side) of the swing center P (projection 7-2) of the needle cover 6 is moved to the needle leg. The needle cover 6 that covers the needle 1 is locked and held by pressing and swinging in the direction so that the needle cover 6 covers the needle 1 (the state of FIG. 4C). Then, the locked state is released by pressing and swinging the rear half side (upper side 603 rear end side) of the needle cover that is lifted and separated from the needle leg in the needle leg direction (Fig. 4 (b) state).

The top dead center locking portion 9 pushes and rocks the rear half side of the rocking center P to release the locking lock state of the needle cover by the bottom dead center locking portion, and then the needle cover. When the needle covers are slid and retracted to the top dead center position where 1 is completely exposed, they are engaged with each other and locked to firmly hold the needle at the top dead center position. The locking portion 9 is provided with the above-mentioned concave portions 9-1 provided on both side surfaces of the front end of the narrow portion 2-2 of the needle leg 2 and the convex portions 9 provided on both inner surfaces of the front end of the narrow groove portion 10 of the needle cover 6. And -2, the needle cover is slid and retracted from the bottom dead center position so as to be fitted and locked to each other to lock and hold the needle cover at the top dead center position (Fig. 4 (a)). State). The locked state is released by sliding the needle cover 6 forward from the top dead center position to the bottom dead center position (FIG. 4).
(A) A solid line to a chain double-dashed line).

Next, a brief description will be given of an example of use of the compass having the above-described construction in detail. After use, the needle leg 2 is grasped with the index finger, middle finger, and ring finger, and the fingertip (abdomen) is held on the thumb. It is along the slip stopper 12 of the upper side portion 6-3 of the cover 6 (from the solid line to the alternate long and two short dashes line in FIG. 4A). In this state, the needle cover 6 is slid forward to the bottom dead center position (see FIG.
(State of solid line in (b)), then swing center P (projection 7-
The front half side of the needle cover 6 is pressed and oscillated in the direction of the needle leg 2 with the point 2) as the fulcrum (state of the chain double-dashed line in FIG. 4B). Then,
The convex portion 8-2 of the bottom dead center locking portion 8 of the needle cover 6 is fitted and locked in the recess 8-1 of the bottom dead center locking portion 8 of the needle leg 2. As a result, the needle cover 2 covering the needle 1 is firmly held by the locking lock of the convex portion 8-2 with respect to the concave portion 8-1.

On the other hand, when using the needle leg 2 as described above.
Grip the fingertips of the thumb along the rear half of the upper side 6-3 of the needle cover 6 that floats up and separates from the needle leg 2, and swing center P
With the (projection 7-2) as a fulcrum, the second half of the needle cover 6 is attached to the needle leg 2
And oscillates in the direction (from the state of FIG. 4C to the state of FIG. 4B). Then, the protruding portion of the bottom dead center locking portion 8 of the needle cover 6
8-2 is disengaged from the concave portion 8-1 of the bottom dead center locking portion 8 of the needle leg 2 and the locked state is released (from the two-dot chain line state in FIG. 4B to the solid line state). . Next, place your thumb on the upper side 6-of the needle cover 6.
The needle cover 6 is slid back to the top dead center position along the line 3 (from the state of FIG. 4B to the state of FIG. 4A). Then, the convex portion 9-1 of the top dead center locking portion 9 of the needle cover 6 fits into the concave portion 9-1 of the top dead center locking portion 9 of the needle leg 2 and is locked. As a result, the needle cover 6 has a convex portion 9-2 with respect to a concave portion 9-1.
The lock is firmly held by the lock lock and the needle 1 is kept in the exposed use state.

Further, in the present invention, as shown in FIG. 5, the window 1 having a substantially inverted U shape is formed in the needle tip coating portion 6-1 at the front end of the needle cover 6.
Provision of 3 is also optional, and in this case, when the needle cover 6 is slid and retracted to the top dead center position where the needle 1 is exposed,
The narrow portion 2-2 is flush with the lower end of the needle leg 2 from which the needle 1 projects so that 13 fits into the narrow portion 2-2 of the needle leg 2 as well as the narrow groove portion 10 of the needle cover 6. It is preferable to form it.

FIG. 6 shows another embodiment of the drafting tool of the present invention showing a device in place of the compass described in the above embodiment. Since the basic configuration is the same as the detailed description of the above-described embodiment, the same reference numerals are used for the same components, and the details are omitted.

[0022]

Since the drafting tool such as the compass or device having the needle of the present invention is constructed as described above, it has the following operational effects. According to the present invention, the operation of the needle cover for covering or exposing the needle protruding from the lower end of the needle leg is performed in two stages: swinging in the needle leg direction with the swing center P as a fulcrum and sliding vertically. Since it is configured so that it can be carried out by holding it, it is not necessary to always provide a retracting port for projecting or retracting the needle in the needle tip covering portion at the front end portion of the needle cover as in the conventional case. Therefore, there is no danger of the needle jumping out even if the needle cover moves backward due to the impact when it is accidentally dropped on the floor or the like.

Also, the holding of the needle cover with respect to the needle leg at the bottom dead center position of the needle cover covering the needle and the top dead center position of exposing the needle is fitted to each other at the bottom dead center position and the top dead center position. Since it is configured to be locked by the locking portion for the bottom dead center and the locking portion for the top dead center that are provided between the needle leg and the needle cover so as to match, The hugging state can be rough. That is, unlike the conventional method, the needle cover is incorporated into the needle leg without adopting the surface friction structure for blunting the vertical slide, which holds the needle cover at the bottom dead center position and the top dead center position by friction resistance. Since the needle cover can be provided, the needle cover can be slid to the bottom dead center position where the needle is covered and the top dead center position where the needle is exposed, without requiring a strong force and with one hand operation.

Therefore, according to the present invention, not only adults but also children (school children) such as elementary school students can easily and smoothly slide the needle cover to cover the needle and expose the needle. It is possible to provide a drafting tool having a needle such as a compass or a device, which is excellent and has a safety measure capable of reliably preventing the needle from popping out even if it is dropped on the floor or the like, and further improved handleability.

[Brief description of drawings]

FIG. 1 is a front view showing a compass which is an example of an embodiment of a drafting tool of the present invention, (a) is a usage state in which a needle is exposed, and (b) is a non-use state in which a needle is covered.

2 is an enlarged cross-sectional view of a main part, (a) is a cross-sectional view taken along the line (a)-(a) of FIG. 1, and (b) is (b)-of FIG.
(B) Line sectional view

FIG. 3 is a bottom view showing the needle cover alone.

FIG. 4 is an enlarged vertical cross-sectional view of a main part showing the movement of the needle cover, (a) shows a state of sliding forward from the top dead center position of the needle cover with the needle exposed, (b) covering the needle. The needle cover that is slid forward to the bottom dead center position of the needle cover is pressed and oscillated in the needle leg direction on the lower half side with the swing center as the fulcrum, and (c) shows the state in which the needle is covered. Show

FIG. 5 shows another embodiment in which a window is provided in the needle tip covering portion of the needle cover, and (a) shows a state in which the needle is slid forward from the top dead center position of the exposed needle cover, (b). Is (a)
(B)-(b) line enlarged cross-sectional view, (c) shows the needle cover in the needle leg direction on the lower half side with the swing center as the fulcrum after sliding forward to the bottom dead center position of the needle cover. Shows the state in which the needle is covered by pressing and rocking

FIG. 6 is a front view of another embodiment of the drafting tool of the present invention showing a device instead of a compass.

[Explanation of symbols]

1: Needle 2: Needle leg 3: Writing leg 4: Opening / closing pivot part 5: Picking 6: Needle cover 6-1: Needle tip covering part 6-2: Both side parts 6-3: Upper side part 7: Holding part 7 -1: Long groove 7-2: Projection part (swing center P) 8: Bottom dead center locking part 8-1: Recessed part 8-2: Convex part 9: Top dead center locking part 9-1: Recessed part 9- 1: convex

Claims (4)

[Claims] 1. A drafting tool having a needle, such as a compass or a divider, between a needle leg having the needle and a needle cover that is swingable in the needle leg direction and vertically slidable. A locking portion that alternately and disengageably locks at two points above and below the bottom dead center position of the needle cover that covers the needle and the top dead center position of the needle cover that exposes the needle. A drawing tool characterized by. 2. A drafting tool having a needle, such as a compass or a divider, comprising: a needle leg having the needle; and a needle cover having a substantially U-shaped cross section for covering the needle. A holding portion is provided for holding the cover slidably in the vertical direction and swingable in the needle leg direction. Further, the needle cover is slid forward to the bottom dead center position for covering the needle between the needle leg and the needle cover. Then, the bottom dead center engaging portion that engages and disengages when the front half side of the swing center of the needle cover is pressed and swung, and the rear half side of the swing center is pressed and swung. A drawing tool, comprising: a top dead center locking portion that locks detachably when the needle cover is slid and retracted at a top dead center position where the needle is exposed. 3. The bottom dead center and top dead center locking portions according to claim 1 or 2 are composed of a convex portion and a concave portion that are fitted and locked with each other, one of which is provided on the needle cover side and the other of which is provided on the needle cover side. A drawing tool, wherein one is provided at a bottom dead center position and a top dead center position on the needle leg side. 4. The needle cover according to any one of claims 1 to 3, wherein the cross section is formed in a substantially U-shape from a material having elasticity and appropriate rigidity, and the needle cover at the front half portion side of the swing center is formed. A drawing tool characterized in that both side edges are provided with both bottom dead center and top dead center locking portions, and slits are provided on the front half side to divide the side edges into left and right parts from the lower end thereof. .