JP2973175B2 - Arbitrary degree brake device for simple drafting machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arbitrary degree brake device for fixing a scale mounting plate of a simple drafting machine at an arbitrary angle.

[0002]

2. Description of the Related Art In general, a simple drafting machine supports a bearing base plate so as to move in parallel on a drafting board by a parallel movement mechanism, and supports a scale mounting plate rotatably on the bearing base plate. It has a basic configuration.
The conventional scale mounting plate includes an index lever for fixing at a predetermined indexing position and a degree fixing lever for fixing at an arbitrary position. When the index lever is pressed, the rotation of the scale mounting plate becomes free, and when the index lever is released, it is clicked at the next indexing angle. The indexing angle is set, for example, every 15 °. When fixing the scale mounting plate at an arbitrary angle irrespective of the indexing angle, the angle of the scale mounting plate is determined while pressing the index lever. , Lock with a fixed lever.

This basic function has no particular problem when the indexing angle by the index lever is frequently used. However, when a large number of arbitrary angles other than the indexing angle are frequently used, the lock of the fixed lever is released each time. The operation and the lock operation have to be repeated, and there is a problem that operability is poor.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an arbitrary degree brake device which can obtain excellent operability, particularly in a use mode in which the angle of a scale mounting plate is changed to an arbitrary different angle. Another object of the present invention is to obtain this arbitrary angle brake device with a simple mechanism.

[0005]

SUMMARY OF THE INVENTION An arbitrary degree brake device for a simplified drafting machine according to the present invention includes a bearing plate plate that moves in parallel on a drafting plate; a scale mounting plate rotatably supported by the bearing plate plate; A brake plate fixed around a rotation axis of the scale mounting plate; a brake shaft movably supported by the scale mounting plate and sandwiching a part of a peripheral edge of the brake plate between the brake head and the scale mounting plate; An arbitrary degree brake lever supported coaxially with the brake axis and moving the brake axis forward and backward by its rotating operation; and biasing the arbitrary degree brake lever in a direction in which the brake head of the brake axis contacts the brake plate. Biasing means for performing the operation.

According to this configuration, when the brake lever is rotated by an arbitrary amount against the urging means, the rotation of the scale mounting plate becomes free, and when the brake lever is released, the brake is applied. That is, since the brake is applied by the operation of releasing the hand, the operability is very good. Further, the configuration is simple, and an inexpensive arbitrary-degree brake device can be obtained.

[0007] The braking device of the present invention can be provided with an indexing function. In one embodiment, the bearing base plate is provided with a disk portion centered on the rotation center of the scale mounting plate, and at least one indexing recess is formed on the periphery of the disk portion, while the scale mounting plate is Has a claw portion that engages with the indexing concave portion, and supports a click lever that is constantly biased to move toward the disk portion. According to this aspect, the indexing function can be added with a simple configuration.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. A horizontal rail (not shown) is provided on the upper part of the drawing board 11 in FIG. 1, and a vertical rail 12 is slidably supported in the horizontal rail in the left-right direction. It is slidably supported. Therefore, the bearing base plate 15 always moves in parallel on the drafting board 11 by the movement of the vertical rail 12 along the horizontal rail and the movement of the vertical rail 12 on the own rail.

As shown in FIG. 2, the bearing base plate 15 has a disk portion 15a at the tip end thereof.
The rotation center shaft 16 of the scale mounting plate 20 and the circular brake plate 18 are fixed by fixing screws 19. The circular brake plate 18 has a larger diameter than the disk portion 15a, and its periphery projects outside the disk portion 15a. A minute scale plate 16b having a minute scale 16a is fixed to the rotation center shaft 16. The above-mentioned bearing base plate 15, rotation center shaft 16, degree scale plate 16b, and circular brake plate 18 are non-rotating elements that do not rotate.

The scale mounting plate 20 is a circular brake plate 1.
8 are arranged along the upper surface. The scale mounting plate 20 includes a mounting portion 20a for the horizontal scale 21, a mounting portion 20b for the vertical scale 22, and a fixing portion 20 for the handle 23.
c, and the handle 23 is attached to the rotation center shaft 1
6 rotatably supported. That is, the scale mounting plate 20 is rotatably supported by the rotation center shaft 16 of the bearing base plate 15, and by rotating the scale mounting plate 20, the directions of the horizontal scale 21 and the vertical scale 22 can be arbitrarily set. . An index 23a corresponding to the minute scale 16a is formed on the handle 23.

A brake shaft insertion hole 24 is formed in the scale mounting plate 20 at a position eccentric from the center of the handle 23, and the male screw portion 25b of the brake shaft 25 is movably supported in the brake shaft insertion hole 24. ing. The brake shaft 25 has a brake head 25 a located on the back surface of the scale mounting plate 20, and the brake head 25 a can sandwich the periphery of the circular brake plate 18 between the brake head 25 a and the scale mounting plate 20. . When the male screw part 25b protruding from the surface of the scale mounting plate 20 is pulled upward, the brake head 25
a and the scale mounting plate 20 come into frictional contact with the circular brake plate 18, and the rotation of the scale mounting plate 20 is locked. That is, the scale mounting plate 20 is a non-rotating circular brake plate 1.
It is fixed to 8. A detent plane portion 25c is formed on the brake head 25a, and the scale mounting plate 20 is integrally provided with a detent projection 26 that engages with the detent plane portion 25c.

A brake lever 28 for moving the brake shaft 25 in the axial direction is provided on the surface of the scale mounting plate 20. The brake lever 28 has a cylindrical body 29 having a female screw portion 29 a screwed with the male screw portion 25 b of the brake shaft 25, and an operating portion 30 fixed to the cylindrical body 29. The cylindrical body 29 contacts the surface of the scale mounting plate 20 via the washer 31 and the rotation of the brake shaft 25 is restricted.
When the dial 9 is rotated, the brake shaft 25 moves in the axial direction due to the screwing relationship between the female screw portion 29a and the male screw portion 25b. The brake lever 28 is urged by the torsion spring 32 in a direction in which the cylindrical body 29 pulls up the brake head 25a. The circular brake plate 18 is strongly clamped between them. That is, when no operation force is applied to the brake lever 28 by an arbitrary amount, the scale mounting plate 20 is locked and does not rotate. On the other hand, when the brake lever 28 is rotated by an arbitrary amount against the torsion spring 32, the brake shaft 25 moves in a direction in which the brake head 25a moves away from the circular brake plate 18, and as a result, the scale mounting The rotation of the plate 20 is free.

Accordingly, in the present apparatus having the above-described structure, when the brake lever 28 is pushed in at an arbitrary degree against the force of the torsion spring 32, the rotation of the scale mounting plate 20 becomes free, and the hand is released from the brake lever 28. The scale mounting plate 20 is locked as it is. Since the brake is applied by the action of releasing the hand, the operability is very good.

FIG. 4 shows another embodiment of the present invention. In this embodiment, in addition to the above basic functions, the scale mounting plate 20
Is provided with a click function. Bearing base plate 1
5, one indexing recess 35 is provided around the disk portion 15a.
A click lever 38 having a claw portion 38 a at a tip portion is formed on the scale mounting plate 20 by a shaft 36.
Is pivoted. The click lever 38 is urged by a torsion spring 40 in a direction in which the claw portion 38a comes into contact with the periphery of the disk portion 15a of the bearing base plate 15.
The positions of the indexing concave portion 35 and the claw portion 38a are set so as to engage with each other when the horizontal scale 21 and the vertical scale 22 are at reference positions where they are correctly parallel to the directions of the horizontal rail and the vertical rail 12 of the drafting board 11, respectively. Have been.

According to this embodiment, when the scale mounting plate 20 is rotated after the lock is released by pushing the brake lever 28 by an arbitrary amount, the index recess 35 and the claw 38a are engaged at the reference position. Click feeling is obtained. The number of index recesses can be increased as appropriate.

[0016]

According to the arbitrary draft braking device of the simple drafting machine of the present invention, the rotation of the scale mounting plate becomes free only when an operating force is applied to the brake lever, and immediately after the operating force is released, the scale mounting plate is released. Since the scale mounting plate is locked, the scale mounting plate can be fixed in any direction with good operability. Further, the configuration is simple, and the click mechanism can be easily configured.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of an arbitrary degree braking device of a simplified drafting machine according to the present invention.

FIG. 2 is a back view of the same.

FIG. 3 is a cross-sectional view of part of FIG.

FIG. 4 is a rear view corresponding to FIG. 2, showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Drawing board 12 Vertical rail 15 Bearing base plate 15a Disk part 16 Rotation center axis 18 Circular brake plate 20 Scale mounting plate 21 22 Scale 23 Handle 24 Brake shaft insertion hole 25 Brake shaft 25a Brake head 25b Male screw part 25c Non-rotating Flat part 28 Arbitrary degree brake lever 29 Cylindrical body 29a Female screw part 30 Operation part 32 Torsion spring 35 Indexing concave part 38 Click lever

Claims (2)

(57) [Claims] 1. A bearing plate that moves in parallel on a drafting plate; a scale mounting plate rotatably supported by the bearing plate; a brake fixed to the bearing plate around a rotation axis of the scale mounting plate. Plate; a brake shaft movably supported by the scale mounting plate and sandwiching a part of the periphery of the brake plate between the brake head and the scale mounting plate; a brake shaft coaxially supported with the brake shaft and rotating by the rotating operation. An arbitrary degree brake lever for moving the shaft forward and backward; and urging means for urging the arbitrary degree brake lever in a direction in which the brake head of the brake shaft contacts the brake plate;
An arbitrary degree brake device for a simple drafting machine, comprising: 2. The bearing base plate according to claim 1,
It has a disk part around the center of rotation of the scale mounting plate,
At least one indexing concave portion is formed on the periphery of the disk portion. The scale mounting plate has a claw portion that engages with the indexing concave portion, and a click lever that is constantly biased to move toward the disk portion is provided. Arbitrary degree brake device for a supported simple drafting machine.