JP2956745B2 - Inverting mechanism of scale in parallel ruler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for inverting a scale of a parallel ruler for reasons such as wiping dirt attached to the back of the scale or replacing a drawing.

[0002]

2. Description of the Related Art In general, a parallel ruler is used to draw a drawing by moving a scale in parallel with the drawing, so that dirt on the drawing or pencil dust adheres to the back surface of the scale.
This needs to be cleaned. In addition, when the drawings are replaced, the front side of the scale may become an obstacle.

However, in the conventional parallel ruler, as shown in FIG. 6, a scale 34 is supported on a shaft 33 of a carriage 32 movably provided along rails 31 provided on both sides of a drawing board 30. One end of the bracket 35 is rotatably provided. A torsion coil spring 36 for floating is attached to the shaft 33.
a engages with the hole 37 of the carriage 32 and the other spring piece 3
6b is in contact with the back surface of the scale 34. For this reason,
The scale 34 always floats at a fixed interval from the drawing plate by the spring force of the torsion coil spring 36. However, the flying height of the scale 34 varies depending on the strength of the spring force of the torsion coil spring 36.
9 is formed, and by engaging with the hole 38 of the carriage 32, the flying height is regulated.

However, according to this mechanism, the scale 34
Cannot be inverted, so the back surface of the scale 34 cannot be cleaned. On the other hand, if the scale 34 can be freely inverted, the floating amount of the scale 34 will vary as described above, and the floating spring piece which has been in contact with the lower surface of the scale 34 when the scale 34 is inverted will be described. 36a is exposed above the drawing board 30 as shown by the one-dot chain line, which hinders the work.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks and to provide an inverting mechanism capable of inverting a scale without a floating spring means hindering a drawing operation.

[0006]

In order to achieve the above object, the inverted mechanism of the scale in the parallel ruler according to the present invention can be moved by the same amount in the same direction along rails fixed to both sides of the drawing board. A carriage is provided, a bracket is rotatably mounted on the carriage , and a parallel ruler having a scale attached to the bracket is provided with the carriage.
A torsion coil spring is placed on the side of the
Insert the coil center of the spring into the rotation axis of the bracket,
The two spring pieces of the torsion coil spring are
Engage both spring pieces with a fixed
In addition to restricting the opening, the middle part of the bracket
A projection is formed, and this projection is connected to one of the torsion coil springs.
The scale is brought into contact with the spring piece, and the scale is
That holds the state of being crab floating and wherein the ●.

[0007]

According to the above construction, when it is necessary to invert the scale at the start of the drawing operation, during the operation, or after the end of the operation, the scale may be raised to the pencil case side as necessary. Since the bracket rotates around the support shaft and the scale is inverted, it is possible to clean dirt adhering to the back surface of the scale and replace the drawing.

Further, the spring means is regulated so as not to extend or open beyond a certain amount. That is, since the spring force is set so that the opening angle of the torsion coil spring is maximized, the floating amount of the scale from the drawing board surface is always constant regardless of the spring force of the torsion coil spring. Therefore, the drawing operation can always be performed smoothly.

Further, when the scale is inverted, the load on the spring means is removed, but the opening of the torsion coil spring is increased.
The regulating means for regulating the degree is formed on the side of the carriage.
Because the torsion coil spring is not exposed above the drawing board,
There is no obstacle to work.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a parallel ruler device, which comprises a carriage 3 supporting a scale 2 on both sides of a drawing plate 1,
The scale 2 is moved in parallel by moving the carriages 3 on both sides in the same direction by the same amount.

A pencil case 4 is arranged on the near side of the drawing board 1 and rails 5 are fixed to both sides of the drawing board 1. Two rollers 7 are arranged at both ends (four corners of the drawing plate 1) of the rail 5, and endless steel wires 8 for synchronizing the movements of the carriages 3 on both sides are mounted on these rollers 7 in FIG. It is wound like. The carriage 3 is connected and fixed to both sides of the wire 8 by a connecting mechanism 9 as shown in FIG.

The shafts 21 on both sides of the carriage 3 are shown in FIG.
As shown in FIG. 4, a traveling roller 11 that rotates on a traveling ridge 10 formed on the rail 5 is mounted on the shaft. A spindle 12 is screwed to one end of the carriage 3.
A bracket 13 is rotatably mounted on a shaft, and both ends of the scale 2 are supported on the bracket 13. The support shaft 12 has a torsion coil spring 14 for floating.
Is attached. The coil center 15 of the torsion coil spring 14 is inserted into the support shaft 12, and the ends of both spring pieces 14a and 14b extending from the coil center are bent at right angles to form a pair of engagement holes 16 of the carriage 3, 17
(Each is vertically long), thereby restricting the torsion coil spring 14 from opening beyond a certain amount. A projection 18 is formed at an intermediate portion of the bracket 13, and the projection 18 is in contact with one of the spring pieces 14a. For this reason, the scale 2 floats at a fixed interval from the drawing board 1 by the spring force of the torsion coil spring 14.
The engagement holes 16 and 17 may be integrally formed vertically.

According to the above configuration, when it is necessary to invert the scale 2 at the start of the drawing operation, during the operation, or after the operation is completed, the scale 2 is moved to the pencil case 4 side as shown in FIG. I just need to raise it. Support shaft 12
, The scale 2 is inverted and the scale 2 is inverted, so that the dirt adhering to the back surface of the scale 2 can be cleaned and the drawing can be replaced. When drawing along the scale 2 during drawing, the lower surface of the scale 2 may be pressed against the drawing, and the translation may be performed by moving the scale 2 to the drawing board 1.
Can be carried out in a state of being floated from the surface.

The torsion coil spring 14 has an engagement hole 16,
No. 17 regulates not to open more than a certain amount. That is, since the spring force is set so that the opening angle of the torsion coil spring 14 is maximized, the floating amount of the scale 2 from the surface of the drawing plate 1 is always constant regardless of the spring force. Therefore, the drawing operation can always be performed smoothly.

Further, when the scale 2 is inverted, the load on the one spring piece 14a of the torsion coil spring 14 is removed, but the engagement holes 16 and 17 for regulating the degree of opening of the torsion coil spring 14 are provided on the side surface of the carriage 3. Formed,
Since the ends of the spring pieces 14a, 14b remain engaged with the engagement holes 16, 17, the torsion coil spring 14 is
It is not exposed upward and does not hinder work.

In the above-described example, the restricting means for restricting the opening of the torsion coil spring 14 is formed as the engaging holes 16 and 17, but is not necessarily limited to this example.
For example, as shown in FIG. 5, a configuration may be adopted in which engaging projections 20 are formed on the side surface of the carriage 3 so as to engage with both spring pieces 14a and 14b of the torsion coil spring 14 from above and below. The spring piece may be engaged with the elongated hole or the projection, and the end of the other spring piece may be fixed.

[Brief description of the drawings]

FIG. 1 is a perspective view of a parallel ruler according to the present invention.

FIG. 2 is an explanatory view of a state in which the parallel ruler is stretched by wires.

FIG. 3 is an enlarged cross-sectional explanatory view of a connecting portion between a wire and a carriage in the parallel ruler.

FIG. 4 is a side view showing a mechanism for inverting the scale in the parallel ruler.

FIG. 5 is a side view of another example of the scale inverted mechanism.

FIG. 6 is a side view of a conventional scale inversion mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drawing board 1 2 Scale 3 Carriage 5 Rail 13 Bracket

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B43L 13/02

Claims (1)

(57) [Claims] 1. A carriage is provided which is movable by the same amount in the same direction along rails fixed to both sides of a drawing plate, a bracket is rotatably mounted on the carriage, and a scale is mounted on the bracket. In the parallel ruler, a torsion coil spring is arranged on the side of the carriage,
Rotation of the bracket above the coil center of the torsion coil spring
Insert the two spring pieces of the torsion coil spring into the shaft
Engage the regulating means formed on the side of the carriage
The splint is restricted to a certain opening, and the bracket
A projection is formed in the middle of the torsion coil.
Abut on one spring piece of the spring and attach the scale to the drawing plate.
A scale inverting mechanism in a parallel ruler, characterized in that the scale is held slightly above the surface .