JPH0443353Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a compass that can draw arcs of relatively large radius in signboard creation, construction sites, and the like.

(Prior Art) As a compass capable of drawing a circular arc with a relatively large radius, as shown in FIG.
In addition to preventing the auxiliary rods 51 from becoming unwieldy and long, the fulcrum member 54 has a through hole 55 with a core needle 53 at its lower end, and a writing member 57 with a writing implement 56 such as a pencil. It is known that the auxiliary rod 51 is inserted into the through hole 58, and each member 54, 57 is fixed in a predetermined position with a respective fixing screw 59.

The connector 52 is provided with a through hole 60 that is slightly larger than the cross-sectional shape of the auxiliary rod 51, and the ends of each auxiliary rod 51 are inserted into the through hole 60 so that both ends abut against each other. The two auxiliary rods 51 are connected by tightening the connecting screw 61.

(Problem to be solved by the invention) However, in the above conventional example, the connecting tool located at the connecting part of the auxiliary rod gets in the way and the writing member cannot be moved to the position of the connecting part, so the radius of the arc In the end, there is a problem in that discontinuous portions that cannot be drawn with the fulcrum member fixed are generated.

For this reason, in the above conventional example, the lengths of the plurality of auxiliary rods are made to be different from each other, and the position of the connecting part can be changed by switching the connecting positions of the auxiliary rods, but each time the fulcrum is Since it is necessary to remove the member and the writing member and change the position of the auxiliary rod, a problem arises in that as the range of the radius of the arc that can be drawn is expanded, the difficulty in handling increases.

In view of the above-mentioned problems, the present invention provides a compass that can dramatically expand the radius range of arcs that can be drawn and that can continuously adjust the position of the writing member within that range. With the goal.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a fulcrum member that is provided with a core needle at the lower end and a guide groove on the front side that guides the sliding plate so as to be able to slide in the lateral direction. , a writing part provided on the sliding plate, and an auxiliary member having a proximal part connected to the distal end part of the fulcrum member and having a guide groove on the front side extending the guide groove, A fixing screw for fixing the sliding plate to the fulcrum member or the auxiliary member is inserted into the moving plate and the bottom of each guide groove of the fulcrum member and the auxiliary member so that the sliding plate can slide in the lateral direction. Elongated holes are provided respectively, and the dimension between both ends of the elongated hole of the sliding plate is determined by the dimension between the guide groove of the fulcrum member and the distal end of the elongated hole, and the base of the guide groove and the elongated hole of the auxiliary member. While setting the dimension to be larger than the sum of the dimensions between the two ends, a connecting part that abuts the back surface of the fulcrum member is extended to the proximal part of the auxiliary member, and a fulcrum is attached to the front side of this connecting part. A regulating piece is provided to project from the back side of the elongated hole of the member to restrict vertical swinging of the auxiliary member relative to the fulcrum member, and passes through the elongated hole to connect the connecting piece to the fulcrum member. It is characterized by the provision of connection screws for the purpose of

In the above configuration, the auxiliary member is provided with a plurality of elongated holes, and the dimension between both ends of the adjacent elongated holes is set smaller than the dimension between both ends of the elongated hole of the sliding plate, and the auxiliary member is provided with a plurality of elongated holes. The sum of the dimension between both proximal end parts of the guide groove and the proximal elongated hole and the dimension between the distal end parts of the guide groove and the distal elongated hole is calculated as the sum of the dimension between both proximal end parts of the guide groove and the proximal elongated hole. By setting it smaller than the dimension between the parts,
The present invention is suitable for connecting a plurality of auxiliary members to draw a circular arc with a large radius without causing a large decrease in rigidity due to the opening of the long holes.

Further, by providing the long hole of the auxiliary member with a large-diameter insertion portion through which a fixing screw can be inserted, it is suitable for adjusting the position of the sliding plate by changing the long hole to be used.

(Function) According to the present invention, by bringing the connecting portion of the auxiliary member into contact with the back surface of the fulcrum member and engaging the regulating piece of the connecting portion into the elongated hole of the fulcrum member, the auxiliary member can be moved up and down with respect to the fulcrum member. It is possible to restrict directional swings. In addition, by inserting a connecting screw into the elongated hole and tightening this fulcrum member with the connecting part, the auxiliary member can be attached to the fulcrum member without creating a new hole for the connecting screw in the fulcrum member and without wobbling. can be connected to. At this time, since the connecting portion is located on the back side of the fulcrum member, the connecting portion does not get in the way even when the sliding plate is slid between both guide grooves.

Further, between the two guide grooves, the long hole of the sliding plate overlaps with the long hole of at least either the fulcrum member or the auxiliary member, so the sliding plate can be fixed with the fixing screw in the overlapping portion. In addition, when fixing using the elongated hole of a fulcrum member, the said auxiliary member is not used. As a result, the position of the sliding plate can be continuously adjusted in the connecting portion.

Furthermore, by providing a plurality of elongated holes in the auxiliary member and setting the dimension between the ends of both adjacent elongated holes to be smaller than the dimension between both ends of the elongated hole of the sliding plate, the size of the sliding plate in the auxiliary member is It is possible to compensate for the decrease in rigidity of the auxiliary member due to the opening of the elongated hole without impairing the continuity of the adjustment position. As a result, even when the compass of the present invention is made of synthetic resin to reduce the overall weight, deformation of the auxiliary member due to the decrease in rigidity can be suppressed, and the accuracy of the radius of the arc to be drawn can be ensured.

Also, the sum of the dimension between the proximal end portions of the guide groove and proximal elongated hole of the auxiliary member and the dimension between the distal end portions of the guide groove and distal elongated hole is determined as By setting the dimension smaller than the dimension between both ends of the elongated hole, when connecting multiple auxiliary members, the elongated hole of the sliding plate overlaps at least one of the elongated holes of each auxiliary member at the connecting portion of both. Therefore, the sliding plate can be fixed at any position in the connecting portion between both auxiliary members. The connection between the auxiliary members can be performed in substantially the same manner as the connection with the fulcrum member after the connecting portion of the distal side auxiliary member is applied to the distal side back surface of the proximal side auxiliary member. As a result, it becomes possible to add a plurality of auxiliary members as appropriate, and the range of circular arcs that can be drawn can be dramatically expanded.

In addition, by providing a large diameter insertion part in the long hole of the auxiliary member through which the fixing screw can be inserted, the selection of the long hole to be used can be made with the fixing screw attached to the sliding plate, making it easier to handle. can be made even easier.

(Example) An example of the present invention will be described based on FIGS. 1 to 7.

In the overall configuration shown in FIG. 1, 1 is a fulcrum member for obtaining the center of an arc to be drawn; 2 is a writing member that removably holds a writing instrument 3 such as a pencil, a pencil, or a felt-tip pen; 4 is this writing member 2; A sliding plate 5 integrally formed with is an auxiliary member that can be added to the fulcrum member 1 as appropriate.

A center needle 6 is provided at the lower end of the fulcrum member 1, and a knob 7 is formed at the upper end for supporting the center position by hand so that the center position does not move when drawing an arc. A wide portion 8 that extends to both left and right sides is formed in the vertically intermediate portion of this fulcrum member 1 . In this embodiment, the left side portion of the wide portion 8 is wider in the lateral direction than the right side portion. A guide groove 9 having a rectangular cross section is formed on the front side of the wide portion 8 so as to extend through both left and right ends. This guide groove 9 guides the sliding plate 4 so as to be able to slide in the lateral direction. A long hole 10 is formed in the bottom of the guide groove 9 along its longitudinal direction.

The sliding plate 4 has the guide groove 9.
A long hole 11 is provided whose vertical position coincides with the long hole 10 when the device is mounted on the device. 12 is a fixing screw for fixing the sliding plate 4 to the fulcrum member 1 or the auxiliary member 5, and the male screw part 12 has a hexagonal head.
a, and a female threaded portion 12b that is screwed into the shaft portion of this male threaded portion 12a. The outer peripheral surface of the female threaded portion 12b is knurled so that it can be easily rotated relative to the male threaded portion 12a. Said long hole 11
A stepped portion 13 is formed on the front side of the holder to prevent the male screw portion 12a from rotating together.

The writing member 2 equipped with this sliding plate 4 has a V-groove shaped writing instrument receiving portion 1 on the tip side of the sliding plate 4.
It is equipped with 4. Although the left and right opening angle of the writing instrument receiving portion 14 is set to about 110° in this embodiment, it can be designed as appropriate depending on the outer diameter of the writing instrument 3 to be used. A support protrusion 17 for pivotally supporting the clamping member 15 via a pivot pin 16 is provided at a position spaced apart from the receiving portion 14 at an appropriate distance from the base end of the sliding plate 4 in a vertically protruding manner. . The holding member 15 has a pivoting protrusion 1 which is pivotally attached to the supporting protrusion 17 so that its tip abuts on the bottom of the groove of the receiving portion 14.
8 on the top and bottom. A torsion spring (not shown) is fitted onto the pivot pin 16 , and both ends thereof engage the sliding plate 4 and the clamping member 15 on the proximal side, and the distal end of the clamping member 15 engages with the receiving part 14 . It is rotatably biased so that the writing instrument 3 can be held between them.
In this embodiment, anti-slip materials 19 of the writing instrument 3 are attached to the top and bottom of the inner surface of the receiving portion 14.

The auxiliary member 5 has an I-shaped cross section, and a groove with a rectangular cross section on the front side constitutes a guide groove 20 that slidably guides the sliding plate 4 in the lateral direction. The cross-sectional shape of this guide groove 20 and the guide groove 9 of the fulcrum member 1
The cross-sectional shape of is the same as that of . Elongated holes 21 are formed along the longitudinal direction in the distal end portion and the proximal end portion of the bottom surface of the guide groove 20, respectively. The vertical positions of these elongated holes 21 are such that the elongated holes 1 of the sliding plate 4 are
It is set to match 1. Each long hole 21
A large diameter portion 22 is provided at the proximal end portion of the slide plate 4, through which the female threaded portion 12b of the fixing screw 12 attached to the sliding plate 4 can be inserted. Further, a receiving seat 23 for the female threaded portion 12b is recessed in the rear side peripheral edge of each elongated hole 21. Incidentally, in the vicinity of the large diameter portion 22 of this receiving seat 23, there is provided the female screw portion 12 that moves in the longitudinal direction along the elongated hole 21 on the back side of the auxiliary member 5.
In order to prevent the thread b from moving into the large-diameter insertion part 22 and slipping out to the front side, as shown in FIG. .

Proximal long hole 21 and distal end long hole 21 of auxiliary member 5
The distance between them is such that the dimension between the distal end of the proximal elongated hole 21 and the large diameter portion 22 of the distal elongated hole 21 is larger than the dimension between both ends of the elongated hole 11 of the sliding plate 4. is also set to small. Further, the longitudinal position of the large diameter portion 22 of the proximal elongated hole 21 is such that the large diameter portion 22 and the fulcrum member 1 The dimension between the proximal end of the long hole 10 and the end of the long hole 10 is set to be smaller than the dimension between both ends of the long hole of the sliding plate 4. The dimension between the distal end of the distal elongated hole and the distal end of this auxiliary member 5 is the same as the dimension between the distal end of the fulcrum member 1 and the distal end of its elongated hole 10. The dimensions are approximately the same.

A connecting tongue piece (connecting piece) 24 that comes into contact with the back side of the fulcrum member 1 when the auxiliary member 5 is connected to the fulcrum member 1 is integrally formed on the back side of the proximal side of the auxiliary member 5 . The connecting tongue piece 24 has rearward reinforcing flanges 24a on three sides thereof, and as shown in FIG. 7, two reinforcing beads 24b are provided to protrude in the horizontal direction. The step dimension between the front surface of the connecting tongue piece 24 and the bottom surface of the guide groove 20 of the auxiliary member 5 is made to match the thickness dimension of the bottom surface of the guide groove 9 of the fulcrum member 1. Therefore, when the auxiliary member 5 is connected to the fulcrum member 1, both guide grooves 9,
The bottom surface of 20 is flush. At approximately the vertical center of the connecting tongue piece 24, a regulating protrusion (regulating piece) 25 is provided as an auxiliary member, which engages into the elongated hole 9 of the fulcrum member 1 from the back side when the auxiliary member 5 is connected to the fulcrum member 1. It protrudes at two locations along the longitudinal direction of 5. The protruding dimension of the regulating protrusion 25 is set to be slightly smaller than the thickness dimension of the bottom surface portion of the guide groove 9 of the fulcrum member 1. Between these protrusions 25, the auxiliary member 5 is connected to the fulcrum member 1.
The male threaded portion 26a of the connecting screw 26 for connecting to the
is fixed in a protruding manner. The head of this male threaded portion 26a is embedded and fixed in the rear side portion of the connecting tongue piece 24. The shaft portion of the male threaded portion 26a passes through the elongated hole 9 of the fulcrum member 1 during connection. The female threaded portion 26b of the connecting screw 26 consists of a nut that is screwed onto the shaft portion of the male threaded portion 26a, and a large diameter knob portion into which the nut is embedded and fixed.

In the above configuration, when the auxiliary member 5 is not used, when one or two auxiliary members 5 are used,
The case where the elongated hole 21 of the auxiliary member 5 is selectively used will be explained based on FIGS. 2 to 5.

When in use, the writing member 2 first presses the proximal end of the clamping plate 15 in the direction of the sliding plate 4 against the biasing force of the torsion spring, thereby creating a gap between the distal end and the writing instrument receiving portion 14. Insert the writing instrument 3 into and release the pressure. Thereby, the writing instrument 3 can be clamped and fixed between the tip portion and the receiving portion 14.

When the radius of the arc to be drawn is small (first
), the fixing screw 12 is inserted from the elongated hole 13 of the sliding plate 4.
is removed, and the sliding plate 4 is attached to the guide groove 9 of the fulcrum member 1. In this case, the auxiliary member 5 is not used. The shaft portion of the male threaded portion 12a of the fixing screw 12 is inserted into the long hole 13 of the sliding plate 4 and the long hole 10 of the fulcrum member 1, and the female threaded portion 12b of the fixing screw 12 is inserted into the back side of the fulcrum member 1. screw onto the shaft portion. In this state, the sliding plate 4 is moved laterally along the guide groove 9 of the fulcrum member 1, and the dimension between the tip of the central needle 6 of the fulcrum member 1 and the tip of the writing instrument 3 of the writing member 2 is Turn the female threaded portion 12b at a position with a predetermined radius. At this time, since the head of the male threaded portion 12a is restricted from co-rotating by the stepped portion 13 on the front side of the elongated hole 11 of the sliding plate 4, the rotating operation of the female threaded portion 12b can be easily and reliably performed. It can be carried out. Thereby, the sliding plate 4 can be fixed to the fulcrum member 1, and a circular arc with a predetermined radius can be drawn. Note that the radius of the arc that can be drawn in this case is between the distal end of the elongated hole 10 of the fulcrum member 1 and the proximal end of the elongated hole 11 of the sliding plate 4, as shown by the solid line in FIG. The maximum L ₁ is obtained at the position where the two parts match, and the minimum L ₀ is obtained at the position shown by the imaginary line in the figure.

When using one auxiliary member 5, there is a second case in which the long hole 21 on the proximal end of the auxiliary member 5 is used as shown in FIG. 3, and a second case in which the long hole 21 on the distal end is used as shown in FIG. This is divided into a third case where .

In the second case, the connecting tongue piece 24 of the auxiliary member 5 is applied to the back side of the fulcrum member 1, and the regulating protrusion 25 and the shaft of the male threaded part 26a of the connecting screw 26 are attached to the fulcrum member 1.
The connecting screw 26 is inserted into the elongated hole 10 from behind, and the female screw portion 26b of the connecting screw 26 is screwed into the shaft portion and tightened. Thereby, the auxiliary member 5 can be connected to the fulcrum member 1, and both guide grooves 9 and 20 can be connected. Next, the sliding plate 4 is attached to the guide groove 20 of the auxiliary member 5 with the fixing screw 12 attached to its elongated hole 11, and the female threaded portion 12b is inserted into the large diameter portion 22 of the elongated hole 21 of the auxiliary member 5. Insert. Insert the fixing screw 12 into this elongated hole 21.
When the female threaded portion 12b passes over the small protrusion 27 of the receiving seat 23 on the back side, tighten the female threaded portion 12b slightly. In this state, the sliding plate 4 is moved within the guide groove 20 and fixed at a position where the dimension between the center needle 6 and the writing instrument 3 is the radius of the circular arc to be drawn. In this case, the radius is the maximum at the position where the sliding plate 4 is shown by the solid line in Figure 3.
L ₃ , and the minimum L ₂ at the position shown by the imaginary line in the figure. In addition, the minimum radius L ₂ in this case is the auxiliary member 5
Since the radius is smaller than the maximum radius L ₁ when not using , the radius of the arc that can be drawn in both the first and second cases expands to L ₃ to _{L 0} .

In the third case where the elongated hole 21 on the tip side is used in one auxiliary member 5, the maximum radius L ₅ is at the position shown by the solid line in FIG. 4, and the minimum radius L ₄ is at the position shown by the phantom line in the same figure. Since the minimum radius L ₄ in this case is smaller than the maximum radius L ₃ in the second case, the radius of the arc that can be drawn in the first to third cases is L ₅ to _{L 0} . Expanding.

When selecting and using two auxiliary members 5, by connecting the second auxiliary member 5 to the first auxiliary member 5 in the same manner as described above, as shown in FIG.
A radius in the range L ₆ to _{L 0} can be drawn.

The present invention can be configured in various ways other than those shown in the above embodiments.

For example, one auxiliary member can be provided with three or more elongated holes, and three or more auxiliary members can also be used. In that case, the lengths of each auxiliary member 5 and its long holes may be different from each other. Further, in the above embodiment, the guide groove is formed to have a rectangular cross section, and the sliding plate is configured to be attachable to and detachable from the guide groove at any position, but in the normal sliding position, the sliding plate does not guide. Both can be formed in a shape that prevents them from falling out of the groove. Further, in the embodiment described above, a ready-made writing implement can be attached to and detached from the writing member, but the writing member itself may be provided with a writing section dedicated to this compass.

(Effect of the invention) Since the present invention has the above-described structure and operation, by appropriately selecting and using auxiliary members, the range of the radius of the circular arc that can be drawn can be dramatically expanded, and moreover, within that range, The radius can be adjusted continuously.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing the overall configuration of the embodiment of the present invention, Fig. 2 is a front view showing the adjustable range of the radius when no auxiliary member is used, and Fig. 3 is when one auxiliary member is used. and a front view showing the adjustable range of the radius when the proximal elongated hole is used.
The figure is a front view showing the adjustable range of the radius when using one auxiliary member and the elongated hole on the tip side, and Figure 5 shows the adjustable range of the radius when using two auxiliary members. The front view shown in Fig. 6 is the 3rd
7 is a sectional view taken along line AA in the figure, FIG. 7 is a sectional view taken along line BB in FIG. 5, and FIG. 8 is a front view of the conventional example. 1... Fulcrum member, 2... Writing member, 4... Sliding plate, 5... Auxiliary member, 6... Center needle, 9, 20...
Guide groove, 10, 11, 21... Long hole, 12...
Fixing screw, 22... Large diameter insertion part, 24... Connecting part, 25... Regulating piece, 26... Connecting screw.

Claims (1)

[Claims for Utility Model Registration] (1) A fulcrum member provided with a center needle at the lower end and a guide groove on the front side for guiding the sliding plate so as to be slidable in the lateral direction, and a fulcrum member provided on the sliding plate. It has a writing part, and an auxiliary member having a guide groove on the front side whose base side part is connected to the tip side part of the fulcrum member and extends the guide groove, and the sliding plate, the fulcrum member, and the auxiliary member. A long hole is provided at the bottom of each guide groove through which a fixing screw for fixing the sliding plate to a fulcrum member or an auxiliary member is inserted so that the sliding plate can slide in the lateral direction. The dimension between both ends of the elongated hole is the dimension between the guide groove of the fulcrum member and both distal ends of the elongated hole, and the dimension between the guide groove of the auxiliary member and both proximal ends of the elongated hole. On the other hand, a connecting part that abuts the back surface of the fulcrum member is extended to the base end side of the auxiliary member, and a connecting part that contacts the back side of the fulcrum member is attached to the front side of the connecting part from the back side. A regulating piece is protruded to restrict vertical swinging of the auxiliary member with respect to the fulcrum member, and a connecting screw is provided to pass through the elongated hole and connect the connecting piece to the fulcrum member. A compass featuring (2) A plurality of elongated holes are provided in the auxiliary member, and the dimension between both ends of the adjacent elongated holes is set smaller than the dimension between both ends of the elongated hole of the sliding plate, and the guide groove of the auxiliary member and The sum of the dimension between both proximal ends of the proximal elongated hole and the dimension between both distal ends of the guide groove and the distal elongated hole is calculated as 2. The compass according to claim 1, wherein the compass is set to be smaller than the size of the compass. (3) The compass according to claim 1, wherein the elongated hole of the auxiliary member is provided with a large diameter insertion portion through which a fixing screw can be inserted.