JPH0232997B2 - RENZOKUSHIGATAJIDOSEIZUKINOKAMIOKURISOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The object of the present invention is to eliminate problems in paper feeding caused by static electricity generated on paper in continuous paper type automatic drafting machines.

First, an outline of a conventional continuous paper type automatic drafting machine will be explained using figures.

FIG. 1 is a sectional view of a main part of a conventional continuous paper type automatic drafting machine.

Continuous paper type automatic drafting machines generally have an unwinding drum 1,
It includes a drawing drum 2, a winding drum 3, a drawing device 4, etc. First, the paper 5 is pulled out from the unwinding drum 1, and the leading end is placed along a part of the circumferential side of the drawing drum 2. When drawing, the drawing drum 2, unwinding drum 1, and take-up drum 3 are rotated to repeatedly move the paper 5 back and forth in the X-axis direction, which is the direction in which the paper is pulled out, and during this time the drawing instrument 4 Drawing is performed by repeatedly moving back and forth in the Y-axis direction perpendicular to the X-axis direction on the paper 5 that moves along the drawing drum 2.

In order to enable high-speed movement of the paper 5 during drawing, two U-shaped containers 6 are provided at the front and rear of the drawing drum 2 in the X-axis direction, a paper slack portion 7 is created there, and the paper is attached to the lower part of the U-shaped container 6. Exhaust pipe 8
By constantly exhausting the air under the paper in the paper slack section 7 to the outside in the direction of arrow a by the vacuum exhaust device 9, the paper 5 is prevented from floating, and the unwinding drum 1 and the winding drum 3 are By controlling the rotation so that the slack of the paper 5 in the paper slack portion 7 is approximately the same, paper feeding by the drawing drum 2 is ensured without applying excessive tension to the paper 5.

However, on the other hand, there is a disadvantage that the paper 5 comes into contact with the sliding guide surface 6a inside the U-shaped container 6, and the friction increases the torque required to rotate the drawing drum 2, and the paper 5 wrinkles. Furthermore, static electricity is generated on the paper 5 due to friction between the paper 5 and each of the drums, and the paper 5 is electrically attracted to the sliding guide surface 6a, further aggravating the above-mentioned drawbacks.

FIG. 2 is a graph of actually measured values showing the relationship between the relative humidity immediately after drawing and the surface potential of the paper. In this figure, the horizontal axis shows the relative humidity (%), and the vertical axis shows the surface potential of each paper when three types of paper A, B, and C are moved back and forth at the same speed in kv. The surface potential of the paper increases due to static electricity generated on the surface of the paper due to friction. The surface potential varies greatly depending on the material composing the paper, the smoothness of the surface, the material of the drum, the relative humidity of the air, etc.
As shown in the figure, the surface potential of the paper may reach several tens of kilovolts during drawing.

Therefore, static electricity of opposite polarity to the static electricity generated on the surface of the paper 5 is generated on the sliding guide surface 6a, and the paper 5
The paper 5 may be electrically attracted to the sliding guide surface 6a, and in extreme cases, it may become impossible to move the paper 5.

The present invention has a structure capable of applying static electricity to part or all of the slide guide surface 6a consisting of the four surfaces, that is, it is connected to a DC high voltage generating means such as a DC high voltage power supply, and is connected to, for example, a charging plate and an insulator. The structure is equipped with a charging means consisting of the like, and furthermore, by grounding a part of the slide guide surface 6a as necessary, it is possible to reduce dry friction between the paper 5 and the slide guide surface 6a and eliminate electrostatic attraction force. By doing so, it is possible to provide a paper feeding device that has fewer of the above-mentioned drawbacks.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 3 is a sectional view of essential parts of an automatic drawing machine equipped with a paper feeding device according to an embodiment of the present invention, and FIG. 4 is an enlarged sectional view of the U-shaped container surrounding the U-shaped container shown in FIG. The same reference numeral indicates the same functional part. In this embodiment, a charging plate, which will be described later, is provided on a part of the slide guide surfaces 18' of the two U-shaped containers 18 shown in FIG. 3, and the slide guide surfaces 18'' are grounded. In the figure, the U-shaped container 18 is provided with a charging plate 11 on a part of the sliding guide surface 18' as described above.The charging plate 11 is insulated from other components of the U-shaped container 18 by an insulator 12. The terminal 13 is electrically connected to a DC high-voltage power source 17 which is provided outside the U-shaped container 18 and includes an AC power source 14, a rectifier 15, a variable resistor 16, etc. The charging plate 11 has a variable resistor 16. By changing the resistance value, a potential is applied that has the same polarity as the static electricity generated on the surface of the paper 5 and generates static electricity to the extent that the paper 5 does not repel and come into contact with the sliding guide surface 18'.

On the other hand, the other sliding guide surface 18'' of the U-shaped container 18
is grounded by a ground terminal 19.

When the paper 5 charged with static electricity on its surface enters the U-shaped container 18 having the above-described structure, the paper 5 is charged with static electricity of the same polarity as the paper 5 charged on the charging plate 11. As a result, a gap is created between the paper 5 and the sliding guide surface 18', and the air sucked by the exhaust pipe 8 passes through the gap and is sucked. In order to form a stable air film between the paper 5 and the slide guide surface 18', the paper 5 is placed on the slide guide surface 18'.
8', therefore, the binding force due to friction is eliminated, and the paper 5 can move smoothly. On the other hand, when the charged paper 5 passes through the grounded sliding guide surface 18'', the static electricity on the paper 5 disappears when it comes into contact with the slide guide surface 18'', and when the paper is subsequently moved, no electric attraction force is generated and the machine Only the frictional force remains.

Next, other embodiments according to the present invention will be described with reference to the drawings. FIG. 5 is an enlarged sectional view of a U-shaped container enclosure according to another embodiment of the present invention, in which the same numbered parts as in FIGS. 1, 3, and 4 indicate the same functional parts.

The difference between this embodiment and the previous embodiment is that, as shown in FIG.
8″ also has the sliding guide surface 1 in the above embodiment.
A charging plate 11' similar to that provided in 8', an insulator 1
2', a terminal 13' of the charging plate 11' is provided, and the terminal 13' is electrically connected to the DC high voltage power supply 17.
A voltage is applied to the charging plate 11' in the same way as the charging plate 11. In this case, the static electricity generated on the paper 5 is not eliminated on the slide guide surface 18'', but a grounding roller (not shown) is provided to eliminate the static electricity.In this case, the paper 5 has almost no mechanical friction inside the U-shaped container 18. can be moved to.

In the above embodiment, the charging plate 11 was provided on the slide guide surface 18' of the U-shaped container 18, but various combinations may be implemented, such as providing it only on the slide guide surface 18'' and grounding the slide guide surface 18'. Of course it is possible.

As explained above, according to the present invention, the mechanical and electrical restraining force on the paper 5 is reduced, so the paper 5 moves smoothly, so wrinkles do not occur, and the driving force of each drum can be reduced. The effect is extremely large.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the main parts of a conventional continuous paper type automatic drawing machine, Fig. 2 is a graph of actual measured values showing the relationship between relative humidity immediately after drawing and paper surface potential, and Fig. 3 is a graph of the main part of a conventional continuous paper type automatic drawing machine. FIG. 4 is an enlarged sectional view of the U-shaped container surrounding the U-shaped container shown in FIG. FIG. 3 is an enlarged cross-sectional view of the enclosure of the letter-shaped container. 1... Unwinding drum, 2... Drawing drum, 3... Winding drum, 5... Paper, 6, 18... U-shaped container, 7
...Paper slack portion, 11, 11'...Charging plate, 12,
12'... Insulator, 13, 13'... Terminal, 14... AC power supply, 15... Rectifying element, 16... Variable resistor, 17...
DC high voltage power supply, 18', 18''...sliding guide surface, 1
9...Grounding terminal.

Claims (1)

[Claims] 1 A drawing instrument that reciprocates in the Y-axis direction along the drawing drum reciprocates in the X-axis direction by unwinding drums and take-up drums installed before and after the When drawing on a moving sheet of paper, a U is installed at the front and back of the drawing drum in the X-axis direction to form a slack portion of the sheet of paper, and the bottom of the drum is connected to a vacuum evacuation device.
In a continuous paper type automatic drawing machine with a letter-shaped container,
Connected to a DC high voltage means and charged with static electricity in order to add static electricity of the same polarity as the static electricity generated on the surface of the paper due to drawing to at least a part of the sliding guide surface inside the U-shaped container. A paper feeding device for a continuous paper type automatic drafting machine, characterized in that it is equipped with a charging means capable of electrification.