JPH0128718B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support device for a vertical rail tail of a rail type universal parallel ruler.

In a rail-type flexible parallel ruler, each time the inclination angle of the drawing board changes, the load in the direction perpendicular to the drawing board surface on the tail side of the vertical rail changes. Therefore, in a rail type flexible parallel ruler in which the tail side of the vertical rail is levitated against the drawing surface by magnetic force, when the load on the tail side of the vertical rail against the drawing surface changes, the magnetic force acting between the two changes. As a result, the distance between the vertical rail tail and the drawing board surface varies greatly. As a result, the parallelism of the vertical rail to the drawing board surface is lost, which causes poor adhesion of the vertical straightedge to the drawing board surface.

It has been found that the above defects can be eliminated by forming the rows of magnetic poles of the magnets facing each other into a plurality of rows in which different poles are adjacent to each other. The reason is as follows.

As shown in FIG. 7, magnets 2 and 4 face each other vertically.
If the width and magnetic force of each are constant, the vertical axis is the repulsive force, and the horizontal axis is the gap between the opposing magnets 2 and 4, then the magnets 2 are arranged in 8 rows in parallel so that different poles are adjacent to each other. When the magnets 4 are arranged in eight rows in parallel so that different poles are adjacent to each other, and the magnets 2 and 4 are arranged with the same poles facing each other, the gap-repulsion force characteristic becomes curve 6. 8 is the characteristic curve for 6 rows, 1
0 is the characteristic curve for 4 columns, and 12 is the characteristic curve for 2 columns.

As is clear from the above characteristic curve, as the number of rows of magnets increases and the number of magnetic poles increases, the curve of the characteristic curve becomes steeper. That is, although the repulsive force is large, the attenuation of the repulsive force is also significant as the gap widens. This means that when a predetermined load is applied downward to the magnet 2 to the extent that the magnet 2 does not touch the magnet 4, when this load is changed to a direction that reduces the load, the magnet 2
The conclusion is reached that the change in the gap with respect to the magnets 4 becomes smaller as the number of rows of the magnets 2 and 4 increases.

This conclusion can also be drawn from the magnetic flux density distribution characteristic diagrams showing test results using a Gaussmeter shown in FIGS. 8 to 11. In the figure, the horizontal axis indicates the width of the magnet, and the number 015678 attached to the characteristic curve indicates the distance from the magnetic pole surface. Figure 8 shows a characteristic diagram when magnets are arranged in two rows in parallel so that different poles are adjacent to each other, Figure 9 shows a characteristic diagram when magnets are arranged in four rows, and Figure 10 shows a characteristic diagram when magnets are arranged in four rows. A characteristic diagram showing the state in which the magnets are arranged in six rows is shown, and FIG. 11 shows a characteristic diagram in the state in which the magnets are arranged in eight rows. As is clear from this figure, the magnetic flux density attenuates as it moves away from the magnetic pole face, and when there are many rows of magnets, the attenuation is more significant than when there are fewer rows of magnets. Therefore, if the number of rows of magnets is increased, when one of the magnets is levitated by the repulsive magnetic force against the other magnet, the load applied to one of the magnets toward the other magnet will increase from the maximum value to the minimum value. In order to reduce the change in the opposing gap between the pair of magnets when the magnets change, the number of rows of magnets should be increased in the parallel direction.

The present invention is based on the above idea, and the configuration of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

14 is a drawing board, and 16 is a horizontal rail fixed to the upper edge of the drawing board 14. As shown in FIG. 6, horizontal rail surfaces 18, 20 and vertical rail surfaces 22, 24 are formed along the longitudinal direction. has been done. Reference numeral 26 designates a plate member, and a bracket 28 is rotatably supported on a rising portion of this plate member by a shaft 30, which is rotatable about an axis parallel to the horizontal rail 16. Said plate member 26
The bracket 28 constitutes a lateral moving body 32 that is movable along the lateral rail 16.

A vertical roller 34, horizontal rollers 36 and 38, and a safety roller 40 are rotatably supported on the plate member 26.

The vertical rollers 34 rotatably contact the horizontal rail surface 18, the horizontal rollers 36 and 38 rotatably contact the vertical rail surfaces 22 and 24, and the safety roller 40 responds to the repulsive force of magnets 42 and 44, which will be described later. Therefore, it floats with a slight distance from the horizontal rail surface 20. A magnet 42 made of a plurality of elongated magnetic rubbers with a square cross section is fixed to the horizontal rail 16.

On the externally exposed surface of the magnet 42, there is a magnetic pole band extending in the direction perpendicular to the plane of the paper in FIG.
Multiple rows are formed in parallel in the order of NSNS. The upper end of a vertical rail 46 is fixed to the upper part of the bracket 28. Reference numeral 44 denotes a magnet having the same structure as the magnet 42 fixedly installed on the lower surface side of the horizontal tongue piece of the bracket 28, and the plurality of rows of magnetic pole strips formed on the externally exposed surface of the magnet 44 are the same as the magnetic pole strips of the magnet 42. The homopolar planes are opposite. The magnets 42, 4
Due to the repulsive magnetic force between the vertical rails 46, the upper end side of the vertical rail 46 is completely floating with respect to the surface of the drawing board 14. In FIG. 2, reference numeral 48 denotes a vertical cursor that is movably attached to the vertical rail 46 via rollers, and a head 52 is connected to the vertical cursor 48 via a known head floating mechanism 50. A horizontal straight ruler 54 and a vertical straight ruler 56 are detachably fixed to the mounting plate of the head 52. 58 in Figure 4
is a cover fixed to the tail part of the vertical rail 46, a frame body 60 is fixed to this cover, and the adjusting plate 66 is attached to the shafts of screws 62 and 64 that are screwed into screw holes drilled in the frame body 60. The elongated holes 68 and 70 are slidably fitted together. Reference numeral 72 denotes a support frame fixed to the adjustment plate 66 by screws 74 so as to be finely adjustable in the direction perpendicular to the surface of the drawing board 14;
The right end in the figure shows the head 52 relative to the vertical rail 46.
It protrudes at right angles in the direction of the installation side. Reference numeral 76 denotes a magnet made of a plurality of flexible magnetic rubbers having a square cross section and arranged to fit into grooves formed in the horizontal portion.
In the figure, the magnetic pole strips extending perpendicular to the page are from the left.
Multiple rows are formed in parallel in the order of NSNS.

The magnet 76 is arranged parallel to the horizontal rail 16, the left end of the magnet 76 is located directly below the left side of the vertical rail 46 in FIG. It is separated from the right side surface by a predetermined distance to the right. Reference numeral 78 denotes a fixed rail fixed to the lower edge of the drawing board 14 so as to be parallel to the horizontal rail 16, and a plurality of elongated magnetic rubbers with square cross sections are inserted into grooves formed on the upper surface of the fixed rail. A magnet 80 consisting of the two is arranged to fit together. The magnet 7
On the externally exposed surface of 6, a plurality of parallel rows of magnetic pole bands are formed in the order of NSNS from the left, extending in the direction perpendicular to the plane of the paper in FIG. The magnets 80 and 76 face each other with a predetermined gap between the same polar surfaces due to the repulsive force acting between them.

82 is a safety roller, which is rotatably supported by the support frame 72, and the surface of the roller 82 is connected to the magnet 7.
Due to the repulsive magnetic force of the magnets 6 and 80, it is slightly floating above the surface of the rail 78.

Note that by warming the screws 62 and 64 and sliding the adjusting plate 66 along the longitudinal direction of the vertical rail 46, the magnet 76
The magnetic pole strip of the magnet 80 can be finely adjusted to a position where the same poles exactly oppose the magnetic pole strip of the magnet 80. After the above fine adjustment, the adjustment plate 66 is fixed to the frame 60 by tightening the screws 62 and 64.

Note that any mechanism may be used for the head floating mechanism 50 when implementing the present invention.

Next, the operation of this embodiment will be explained.

When the handle of the head 52 is grasped by hand and force is applied to it in an arbitrary direction parallel to the surface of the drawing board 14, the horizontal moving body 32 moves along the horizontal rail 16, and the vertical cursor 48 moves along the vertical rail 46. can move the head 52 in a desired direction.

When the vertical rail 46 moves horizontally on the drawing board 14 in FIG.
Due to the repulsive magnetic force between 4 and 76 and 80, drawing board 1
It floats completely on all four sides, allowing it to move lightly and smoothly.

When the drawing board 14 is tilted from a horizontal state to an upright direction, for example, at an angle of 80 degrees with respect to the floor surface, the drawing board 1 on the tail side of the vertical rail 46 is more inclined than when the drawing board 14 is in a horizontal state.
The load in the direction perpendicular to the four surfaces is greatly reduced. However, the opposing distance between the magnetic pole surface on the tail side of the vertical rail 46 and the magnetic pole surface on the lower edge side of the drawing board 14 does not widen greatly in response to the reduction of the load, and the change is slight. This is because the magnetic pole surface is composed of multiple rows of parallel magnetic pole strips.

Similarly, even when the drawing board 14 is changed from an upright state to a horizontal state, there is little change in the opposing distance between the magnets 76 and 80.

Since the present invention is configured as described above, it is possible to reduce the opposing distance between the magnet on the tail side of the vertical rail and the magnet on the lower edge of the drawing board as the load changes in the vertical direction of the tail of the vertical rail with respect to the drawing surface. There is an effect that the parallelism of the vertical rail to the drawing board surface can be maintained regardless of changes in the inclination of the drawing board.

[Brief explanation of drawings]

Figure 1 is an overall plan view, Figure 2 is a side view, Figure 3 is an explanatory diagram of the operation, Figure 4 is a front view, Figure 5 is a side view, Figure 6 is a side view, Figure 7 is a diagram of the magnet. Gap-repulsion force characteristic diagram, Figure 8 is a magnetic flux density distribution characteristic diagram for two magnets, Figure 9 is a magnetic flux density distribution characteristic diagram for four magnets, and Figure 10 is magnetic flux for six magnets. Density distribution characteristic diagram, FIG. 11 is a magnetic flux density distribution characteristic diagram in the case of eight magnets. 14...Drawing board, 16...Horizontal rail, 18,20
... Horizontal rail surface, 22, 24 ... Vertical rail surface, 26 ... Plate member, 28 ... Bracket, 30
... Axis, 32 ... Horizontal moving body, 34 ... Vertical roller, 36, 38 ... Horizontal roller, 40 ... Safety roller, 42, 44 ... Magnet, 46 ... Vertical rail, 48 ... Vertical cursor, 52...Head, 5
4, 56...straightedge, 76...magnet, 80...magnet.

Claims (1)

[Claims] 1. A drawing board 14, a horizontal rail 16 disposed on the upper edge of the drawing board 14, and a lateral mover arranged movably and regulated to move along the longitudinal direction of the horizontal rail 16. a vertical rail 46 whose upper end is connected to the horizontal moving body 32, a vertical cursor 48 attached to the vertical rail 46 so as to be movable along it, and a head 52 attached to the vertical cursor 48. In the rail-type flexible parallel ruler, a plurality of rows of magnetic pole strips having mutually different poles are arranged in parallel to the longitudinal direction of the horizontal rail 16 on the tail of the vertical rail 46. On the other hand, on the lower edge side of the drawing plate 14, a plurality of rows of magnetic pole strips are arranged parallel to the longitudinal direction of the horizontal rail 16 so that the same poles as the magnetic pole strips face each other. A vertical rail tail support device characterized in that the tail portion of the vertical rail 46 is levitated relative to the surface of the drawing board 14 by a repulsive magnetic force acting between the magnetic pole bands on the tail side of the vertical rail 46 and the lower edge side of the drawing board 14. .