JPH0353498A - Enclosed type electricity remover - Google Patents

Abstract

PURPOSE:To reduce the installation space by directing a corona discharge electrode to the wave direction so that the just opposite surface of thereof is a wall of an enclosing box, and providing air blow-off ports at the places where the discharge electrode is not seen directly from the outside and an air supply means at the back positions of lines connecting the discharge electrode and earth electrodes. CONSTITUTION:The wave 6 is saved from the emission fog of a corona discharge by directing a corona discharge electrode 1 to the wave 6 direction so that the just opposite surface of the discharge electrode 1 is a wall 10 of an enclosing box 5, and providing air blow-off ports 8a, 8b directed to the wave 6 at the positions where the discharge electrode 1 is bot seen directly from the outside. An air supply means 9 directed to the air blow-off ports 8a, 8b is provided at the back positions of lines connecting the discharge electrode 1 and earth electrodes 3 to prevent that the ion generated in the discharge electrode 1 is drawn by the earth electrodes 3a, 3b. The generated ion is used effectively by forming a flow for driving out the ion from the enclosing box 5 through the air blow-off ports 8a, 8b with the air flow. The installation space is thus reduced.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a light-shielding static eliminator for removing static charges on the surfaces of supports and photosensitive layers in the manufacturing process of photographic light-sensitive materials such as photographic films and photographic paper. It is related to. [Prior Art] In the manufacturing process of photosensitive materials such as photographic film and photographic paper, static charges accumulated on the surfaces of the support and photosensitive layer (hereinafter also referred to as "web") cause the photosensitive emulsion to be transferred to the support. It may cause uneven coating during coating, or the winding of the photosensitive layer 2.
When rewinding, spark discharge occurs, causing photosensitive fog called static marks. To prevent this, especially in the manufacturing process, static eliminators are installed before and after winding and delivery to remove static charges accumulated on the surfaces of the support and photosensitive layer. Conventional static eliminators generate + and - ions by corona discharge because static charges on the surface of the support and photosensitive layer exist sparsely, with 10 charges and 1 charge depending on the location.
An effective method is to neutralize the ions by spraying them onto the support, and a light-shielding static eliminator has been used to avoid photosensitive blurring of the photosensitive layer due to corona discharge for ion generation.

Figure 2 is a side sectional view of this light-shielding static eliminator (al. AA
(in the cross-sectional view). As shown in FIGS. 2(a) and (b), an ion generating means with an insulator 2 surrounding the corona radiation t1t pole l on three sides and a grounding electrode 3 provided on the outside of the insulator 2 is connected to a high voltage tifi 4. This ion generating means is housed in a light-shielding box 5 with its back facing the web 6, and an air outlet 8 is provided in the light-shielding box wall 7 corresponding to the back side of the corona discharge electrode with respect to the web 6, and the corona discharge An air supply means (pipe) 9 was provided facing the electrode 1. The reason for having such a structure is that the corona discharge electrode 1 and the ground electrode 3 are connected to an insulator 2 as an ion generating means. The structure is advantageous in terms of space because the discharge efficiency is good and the structure is concise because the corona discharge electrode 1 is close to the web 6 through the shading box, which corresponds to the back part of the corona discharge electrode. The reason why the air outlet 8 is provided in the light-shielding box wall 7 is to prevent the light emitted from the corona discharge from imparting photosensitivity blur to the photosensitive material.

(Problem to be Solved by the Invention) However, when actually used, the static elimination effect is extremely poor. If the conveyance speed is high, the surface charge may not be completely neutralized, and spark discharge may occur between the web and the pass roller that conveys the web, which may cause photosensitive fog on the photosensitive layer. As a countermeasure, it is necessary to install a large number of these light-shielding static eliminators to sufficiently eliminate static electricity, which requires a large amount of installation space and also causes problems such as high equipment costs due to the use of many high-voltage power supplies. The purpose of the present invention is to solve the above problems, reduce installation space and equipment costs, and provide a light-shielding IT remover that can efficiently eliminate static electricity with a single light-shielding static eliminator. .

[Means and effects for solving the problem] As a result of intensive study on this problem, the inventors of the present invention found that in the conventional device, the corona discharge electrode 1 faces the web 6, and the ground electrode 3 faces the corona discharge electrode 1. It was discovered that due to the close proximity, more than 99% of the ions generated by corona discharge are attracted to the installed electrode 3, and the number of ions used for static elimination (blown onto the web 6 from the air outlet 8) is extremely small. , we have arrived at the present invention.

That is, the above objects of the present invention are as follows: (1) ion generating means for generating ions by a corona discharge electrode and installed electrode; air supply means for blowing the ions onto the web as an air stream from an air outlet; In a light-shielding static eliminator comprising a light-shielding box that houses a generation means and an air supply means and has the air outlet, the corona discharge electrode is directed toward the web, and the corona discharge @
Directly in front of the pole is the wall of the light-shielding box, the air outlet is provided facing the web in a place on the front wall where the discharge electrode cannot be directly seen from the outside, and the discharge electrode and the ground electrode are connected to the air outlet. A light-shielding static eliminator characterized in that an air supply means is provided behind the connecting line.

(2) The light-shielding type shield according to claim 1, wherein the ground electrode is disposed in the light-shielding box on the opposite side of the corona discharge electrode with respect to the air outlet and diagonally in front of the corona discharge electrode. Electric appliances. be admonished by.

In the present invention, the corona discharge electrode is oriented in the direction of the web, the right front of the discharge electrode is the wall of the light-shielding box, and the air outlet is oriented toward the web in a place where the discharge electrode on the front wall cannot be directly seen from the outside. By providing this, the web can be saved from the luminous force caused by corona discharge. In the present invention, by providing an air supply means toward the air outlet behind the line connecting the discharge electrode and the ground electrode, it is possible to prevent the ions generated at the discharge electrode from being attracted to the ground electrode, and to prevent the air from being drawn to the ground electrode. We decided to use the generated ions as effectively as possible by creating a flow that expels the ions from the air outlet and out of the light-shielding box.

In the present invention, the ground electrode is disposed diagonally in front of the corona discharge electrode on the opposite side of the corona discharge electrode with respect to the air outlet in the light-shielding box, so that ions generated at the corona discharge electrode are further transferred to the ground electrode. The rate at which it is attracted is reduced, and it is effectively used to remove static electricity from the web. To further explain the present invention, a needle-like electrode made of metal or carbon fiber is used as the material of the corona discharge electrode.The ground electrode is a conductive material and is used in the form of a plate or a rod.

The high voltage power supply used for corona discharge is DC or AC, the voltage is ~±IOKV, and the frequency in the case of AC is 50
It is about 0Hz. As the air supply means used in the present invention, a propeller fan may be installed in a light-shielding box to draw outside air, but due to space considerations, it is preferable to introduce compressed air through a pipe. The amount of air is selected depending on the effective wind speed from the outlet when blowing ions onto the web. The number of air outlets may be one, two, or three or more. Therefore, it is preferable that the vibrator of the air supply means be matched to the number of air outlets.

It is preferable that the pipe of the air supply means has a diameter of about 5 mm and has a slit corresponding to the width of the air outlet. The dimensions of the slint are 0. Approximately 5 mm is selected. In the present invention, when the ground electrode is provided obliquely in front of the corona discharge electrode, it is preferable that the ground electrode be located 5 to 10 times in front of the corona discharge electrode and 20 to 30 times laterally away from the corona discharge electrode. .

The material of the light-shielding box used in the present invention may be made of brass, but in order to prevent radio wave interference to the outside world, it is preferable to use a material made of iron plate whose surface is coated with plastic paint.

A preferred embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a side sectional view of one embodiment of the light-shielding static eliminator of the present invention. The corona discharge electrode 1 is surrounded on three sides by an insulator 2, and is oriented toward the web 6 in the center of the light-shielding box 5, and has a width corresponding to the width of the web 6 in the middle direction. Metal needle-like bodies serving as discharge electrodes are arranged at appropriate intervals between the widths. In front of the corona discharge electrode, there is a wall 10 of a light-shielding box to serve as a light shield during discharge.
At a place where the discharge electrode l on the front wall is not directly visible from the outside, an air outlet 8a is installed vertically at a distance of 10 to 15 meters from the discharge needle tip.
8b is provided. The slit width of the air outlet is 5m.
The length at the front and back corresponds to the width of the web 6, and it protrudes 5 to 1 (lm) from the light shielding [5].

The ground electrodes 3a and 3b are 5 to 10 m forward of the discharge needle tip of the discharge electrode 1, and 20 to 301 I apart in the vertical direction.
It is located at position IIm and is made of metal. Air supply pipes 9a and 9b as air supply means are plastic pipes of about 5 mI1φ and have a length corresponding to the length of air outlet ports 8a and 8b, and are also slotted and grounded to the discharge electrode l. It is installed behind the line connecting the electrodes 3a and 3b (on the opposite side of the web).

The ions generated by the corona discharge emitted from the discharge electrode l toward the ground electrode 3 by the high voltage from the high voltage power supply 4 show the highest concentration near the discharge electrode.
The ions are sent to the air outlets 8a, 8b by air supplied from the air supply pipes 9a, 9b, and are blown onto the web 6. Therefore, although some of the generated ions are attracted to the ground electrodes 3a and 3b, most of the ions can be used to neutralize the charge on the web 6. The light emitted during corona discharge is blocked by the wall IO on the front of the light-shielding box and does not reach the web, and the convex shape of the air outlet also absorbs the reflected light, so there is no effect on the photosensitive material. .

Since the ions sprayed onto the web by the light-shielding static eliminator of the present invention are sufficiently abundant, one light-shielding static eliminator can be applied to the web even when the surface charge of the web is large or when the web conveyance speed is high. Neutralizes the upper charge, thereby
Products can be produced under good web charging conditions without causing spark discharge between the web and the pass rolls.

[Example] A comparative experiment was conducted using the light-shielding static eliminator of the present invention as shown in Figure 1 and the conventional light-shielding static eliminator as shown in Figure 2. The conditions are: Direct 2IiL': IX source nTREK 664, voltage conditions: -8, -9, -101fV, air pressure at the air supply port: 1.
5) [g/cj, Fukiyama wind speed from Surinoto 7 s/
sec, Discharge electrode: Using SUS304 needle-shaped, as a method for measuring the amount of effective static charge removal, an Al plate grounded through a galvanometer instead of a web was placed opposite the static eliminator, and the distance from the corona discharge electrode needle to the Al was measured. Assuming an installation distance of 50M, A/! when static electricity is removed! The tl flowing through i was measured. The results are shown in Table 1. Table 1 Comparison of the light-shielding static eliminator of the present invention with the conventional static eliminator,
It shows 20 times the static elimination effect. [Effects of the Invention] In order to be effective with conventional static eliminators, there is a problem in terms of space due to the installation of multiple static eliminators. In contrast to the problem of equipment cost, the light-shielding static eliminator of the present invention eliminates surface charge even when the amount of web surface charge is large or when the web conveyance speed is high. It has now become possible to completely neutralize the problems associated with installation space and equipment costs, and has also made a significant contribution to increasing production efficiency.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an embodiment of the light-shielding static eliminator of the present invention, and FIG. 2 is a side sectional view of an example of a conventional light-shielding static eliminator. l... Corona discharge electrode 2... Insulator 3.3a, 3b... Ground electrode 4... High voltage power supply 5... Light shielding box 6... Web 7... Light shielding box on the back side Wall 8.8a, 8b...Air, outlet 9.9a, 9b...Air supply pipe 10...Wall (3 idiots) Figure 1

Claims (2)

[Claims] (1) An ion generating means for generating ions using a corona discharge electrode and a ground electrode, an air supply means for blowing the ions onto the web as an air stream from an air outlet, and housing the ion generating means and the air supply means. In a light-shielding static eliminator comprising a light-shielding box having an air outlet, the corona discharge electrode is oriented toward the web, and the front of the corona discharge electrode is the wall of the light-shielding box, and the discharge electrode on the front wall is directly connected to the light-shielding box. A light-shielding type shielding device characterized in that the air outlet is provided toward the web in a place that cannot be seen from the outside, and an air supply means is provided toward the air outlet behind a line connecting the discharge electrode and the ground electrode. Electric appliances. (2) The light-shielding type shield according to claim 1, wherein the ground electrode is disposed diagonally in front of the corona discharge electrode on the opposite side of the corona discharge electrode with respect to the air outlet in the light-shielding box. Electric appliances.