JPH10128259A - Dust removing device of accumulative phosphor sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a generation of a void due to interception with dust at the time of reading a radiation picture by removing the dust stuck on a surface of an accumulative phosphor sheet from the sheet by adsorbing and leaving electrostatically. SOLUTION: A conductive bar 10 touchable with a dust removing brush B and a grounding means 11 grounding the bar 10 are provided at a dust removing device K. The dust removing brush B is provided just before a radiation picture reading part 6 of a radiation picture reading device, and a tip part of an antistatic brush b1 is arranged at a position brought into contact with the surface of an accumulative phosphor sheet 1. Then the dust stuck on the surface of the accumulative phosphor sheet 1 by charging is removed from the sheet 1 by adsorbing and leaving electrostatically by rubbing the antistatic brush b1 and an electrostatic brush b2. In this way, the generation of the void generated by being intercepted with the dust at the time of reading the radiation picture is prevented and a reliability of the reading is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust removing device for a stimulable phosphor sheet, and more particularly, to a stimulable phosphor which electrostatically removes dust adhering to the surface of the stimulable phosphor sheet. The present invention relates to a dust removing device for a body sheet.

[0002]

2. Description of the Related Art When stimulating light is irradiated on a stimulable phosphor which has been irradiated with radiation such as X-rays in advance, the stimulable phosphor emits stimulating light according to the energy amount of the radiation. By utilizing the property of the stimulable phosphor, a radiation image of a subject such as a human body can be electrically recorded. FIG. 6 shows a schematic configuration of a radiation image reading apparatus using a sheet-like stimulable phosphor sheet. As shown in FIG. 6, the radiation image reading apparatus includes a stimulable phosphor sheet 1 through a subject.
A radiation exposure unit 2 that irradiates radiation onto the stimulable phosphor sheet 1 to accumulate and record image information on the stimulable phosphor sheet 1, and an excitation light irradiation unit that irradiates the stimulable phosphor sheet 1 irradiated with radiation in the radiation exposure unit 2 with excitation light. 3, a photodetector 4 for detecting the amount of stimulated emission of the stimulable phosphor sheet 1 and outputting an electric signal;
A radiation image reading unit 6 including image processing means 5 for processing an image obtained by the photodetector 4, and a stimulable phosphor circulating between the radiation exposure unit 2 and the radiation image reading unit 6 And conveying means 7 for conveying the sheet 1.

In the radiation image reading apparatus, the radiation exposure section 2 irradiates the stimulable phosphor sheet 1 with radiation, and the radiation image information is accumulated and recorded on the stimulable phosphor sheet 1. Here, the material used for the surface of the stimulable phosphor sheet 1 for accumulating and recording a radiation image is a polymer material such as polyethylene, polyamide, and cellulose dielectric. The stimulable phosphor sheet 1 on which the radiation image information has been stored is conveyed to the radiation image reading unit 6 by the conveying means 7. In the radiation image reading unit 6, the stimulable phosphor sheet 1 is irradiated with the excitation light by the excitation light irradiation unit 3. When the excitation light is applied, the stimulable phosphor sheet 1 emits stimulated light. The photodetector 4 detects the stimulated emission light with an electron multiplier or the like and converts the image information into an electric signal. The image information captured by the photodetector 4 is sent to the image processing means 5 and subjected to appropriate image processing. The image information subjected to image processing by the image processing means 5 is output to a monitor or the like. The stimulable phosphor sheet 1 from which the image information has been read is conveyed again to the radiation exposure unit 2 by the conveying means 7. The storable sheet 1 can be reused, and the process starting from the radiation exposure unit 2 described above is repeated, and the radiation images are sequentially read.

However, in the above-mentioned radiation image reading apparatus, when the stimulable phosphor sheet 1 is being conveyed by the conveying means 7, dust floating in the air adheres to the surface of the stimulable phosphor sheet 1. In some cases, reading of a radiation image may be affected. That is, the stimulating light is blocked by the dust adhering to the surface of the stimulable phosphor sheet 1, and the portion to which the dust adheres may become white and the image may not be faithfully read. For example, in the case of an examination of a human body or the like, the white spot may be erroneously recognized as a lesion. If the operator touches and removes the dust at the time of reading the image, the efficiency is poor and the integrity of the device is reduced. Therefore, the radiation image reading apparatus requires a means for removing dust adhering to the surface of the stimulable phosphor sheet 1. Such a dust removing device for a stimulable phosphor sheet is disclosed in, for example, Japanese Patent Application Laid-Open No. 5-68131. According to the technique described in the above-mentioned reference, as shown in FIG. 7, for example, a nozzle 8 provided immediately before a radiation image reading unit 6 blows air on the surface of the stimulable phosphor sheet 1 so that the stimulable phosphor sheet 1 is blown. Dust is removed from the body sheet 1.

[0005]

However, when the dust is charged and adheres to the surface of the stimulable phosphor sheet 1, the dust and the stimulable phosphor sheet 1 are strongly attracted to each other by the electrostatic force. In some cases, dust cannot be completely removed only by blowing air as in a dust removing device for a stimulable phosphor sheet. Other devices for removing dust adhering to the surface of the stimulable phosphor sheet 1 are disclosed in, for example, JP-A-61-17135 and 63-373.
No. 40 discloses this. The dust removing means, which is a main part of the apparatuses described in both documents, is a rotary cleaning roll 9 provided with a cleaning member such as felt, velvet, and fur on its peripheral surface. As shown in FIG. 8, the rotary cleaning roll 9 is provided, for example, immediately before the radiation image reading unit 6, and dust is removed by pressing the rotary cleaning roll 9 against the surface of the stimulable phosphor sheet 1. In this case, it is possible to remove dust and the like charged by friction with the cleaning member. However, in such a dust removing device, there is a problem that the cleaning member rubs against the surface of the stimulable phosphor sheet 1 and the stimulable phosphor sheet 1 itself is charged. The problem of the charging of the stimulable phosphor sheet 1 is that once the stimulable phosphor sheet 1 is charged, other dust floating in the air is absorbed by the stimulable phosphor sheet 1 even if dust is once removed. This is because they are easily attached. In order to solve the problems in the prior art, the present invention has improved a dust removing device for a stimulable phosphor sheet, removes charged dust from the stimulable phosphor sheet, and improves the stimulable phosphor sheet. An object of the present invention is to provide a dust removing device for a stimulable phosphor sheet that can prevent the body sheet itself from being charged.

[0006]

According to a first aspect of the present invention, there is provided a stimulable phosphor sheet for removing dust adhering to the surface of a stimulable phosphor sheet for storing and recording a radiation image. The apparatus is provided with an electrostatic removing means for electrostatically adsorbing and / or separating dust adhering and / or adhering to the surface of the stimulable phosphor sheet and removing the dust from the stimulable phosphor sheet. It is configured as a dust removing device for the stimulable phosphor sheet. As a result, dust that cannot be removed by mechanical operation or air flow can be electrostatically removed from the stimulable phosphor, and the radiation image can be read. Occurrence of white spots, which are sometimes blocked by dust, can be prevented. Therefore, by using the dust removing device for the stimulable phosphor sheet, the reading reliability of the radiation image reading apparatus using the stimulable phosphor sheet is improved.

[0007] In order to electrostatically remove dust adhering to the stimulable phosphor sheet and adhering thereto, for example, the static elimination means is provided with a predetermined amount of dust adhering to the surface of the stimulable phosphor sheet and adhering thereto. The first electric field applying means for applying an electric field, and the second electric field applying means for applying an electric field having a polarity opposite to that of the first electric field applying means to the dust can be provided. In this case, by applying an electric field of positive and negative alternately to the dust charged and adhered to the surface of the stimulable phosphor sheet, the dust electrostatically adhered to the sheet is adsorbed and the dust is removed from the stimulable phosphor sheet. Can be removed. In the case where the static elimination means is a dust removing brush which uses the same material as the stimulable phosphor sheet or a material having a similar charging sequence and removes the dust by contacting the stimulable phosphor sheet, Since the dust removing brush in contact with the stimulable phosphor sheet is made of the same material as the stimulable phosphor sheet or a material having a similar charging sequence, the stimulable phosphor sheet itself is charged by friction with the dust removing brush. Can be prevented. Therefore,
It is possible to prevent the dust that floats in the air from being easily attached due to charging of the stimulable phosphor sheet. Also, since the same material can be charged depending on the contact state, the dust removing brush is charged by enlarging the contact area of each of the brushes of the dust removing brush, and the stimulable phosphor sheet is charged. It is possible to remove dust adhering by electrostatically attracting or separating the dust.
Of course, neutral dust that is not charged is also removed by contacting the dust removal brush.

Further, if a brush charge removing means for removing the charge of the dust removing brush is provided, when the dust attached to the stimulable phosphor sheet is not removed, the charge of the dust removing brush is grounded, for example. Can be removed. Therefore, dust adsorbed on the dust removing brush can be removed from the dust removing brush, so that the dust removing brush is prevented from being clogged. Further, if the handle portion of the dust removing brush is made of a material that is positively and / or negatively charged by rubbing with the dust removing brush, members made of different materials rub against each other. It is easy to be charged and the amount of charge is large, so that dust adhering and adhering to the stimulable phosphor sheet can be easily removed electrostatically. further,
By providing a sheet charge removing means for removing the charge on the surface of the stimulable phosphor sheet by contacting the stimulable phosphor sheet, for example, by grounding the stimulable phosphor sheet,
It is possible to more reliably prevent the stimulable phosphor sheet from being charged. Therefore, it is possible to prevent the stimulable phosphor sheet from being charged and dust from easily adhering.

A second invention is a dust removing device for a stimulable phosphor sheet for removing dust adhering to the surface of a stimulable phosphor sheet for accumulating and recording a radiographic image. A brush for contacting the conductive member, a conductive member for contacting the surface of the stimulable phosphor sheet charged by friction with the brush, and grounding means for grounding the conductive member. It is configured as a dust removing device for the phosphor sheet. By grounding the brush by the conductive member and the grounding means, it is possible to prevent the stimulable phosphor sheet from being charged due to friction with the brush. Further, when the brush is charged, it is possible to remove dust that has been charged and adhered to the surface of the stimulable phosphor sheet.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
The following embodiments embody the present invention and do not limit the technical scope of the present invention. FIG. 1 is a view showing a schematic configuration of a dust removing brush which is an electrostatic suction means according to an embodiment of the present invention.
FIG. 4 is an explanatory view of removing charged dust by the dust removing brush. As shown in FIG. 1A, a dust removal brush B which is a feature of the present invention is an antistatic brush b1 made of the same material as the stimulable phosphor sheet 1 or a material having a similar charging sequence.
And an electrostatic brush b2 that is negatively charged by friction with the antistatic brush b1. Further, as shown in FIG. 1B, a dust removing device K is provided with a conductive bar 10 that can contact the dust removing brush B and a grounding unit 11 that grounds the conductive bar 10. The dust removal brush B is provided, for example, immediately before the radiation image reading unit 6 of the radiation image reading device, and is disposed at a position where the tip of the antistatic brush b1 contacts the surface of the stimulable phosphor sheet 1.

In the above-mentioned dust removing brush B, the reason why the antistatic brush b1 in contact with the stimulable phosphor sheet 1 is made of the same material as the stimulable phosphor sheet 1 or a material having a similar charging line is used. This is to prevent the stimulable phosphor sheet 1 itself and the antistatic brush b1 from being charged by friction between the sheet 1 and the dust removing brush B. This makes use of the property that, when friction is made between objects having similar charging sequences, they are difficult to be charged with each other. Of course, even if the same material is used, charging may occur due to the frictional state. However, since the contact area between the antistatic brush b1 and the stimulable phosphor sheet 1 is small, the antistatic brush b1 almost completely removes the stimulable phosphor sheet 1. There is no charge.
In addition, neutral dust that is not charged is removed by an antistatic brush b1.
And is removed by contact. As described above, if the stimulable phosphor sheet 1 is prevented from being charged, the stimulable phosphor sheet 1 is less likely to electrically attract dust floating in the air, and it is easy to maintain a state in which dust is removed. Become. Conversely, between the antistatic brush b1 and the electrostatic brush b2, the material of the electrostatic brush b2 is on the negative side of the charging line with respect to the antistatic brush b1, and charging easily occurs. Electrostatic brush b
The antistatic brush b1 positively charged by friction with the brush 2 is
As will be described below with reference to FIG. 2, dust adhered to the surface of the stimulable phosphor sheet 1 by being charged is removed.

As shown in FIG. 2, the dust d1 negatively charged and adhered to the surface of the stimulable phosphor sheet 1 is attracted to the positively charged antistatic brush b1 by electrostatic force. Also,
The dust d2 that has been positively charged and adhered to the surface of the stimulable phosphor sheet 1 is repelled rearward in the transport direction by an electric repulsive force acting between the positively charged antistatic brush b1 and finally. Are excluded from the stimulable phosphor sheet 1.
As described above, by charging the dust removing brush B, it is possible to remove the charged dust attached to the stimulable phosphor sheet 1. Further, since the dust removing brush B electrostatically adsorbs dust, the conductive bar 10 and the grounding means 11 are required to prevent the dust removing brush B from being clogged. When the stimulable phosphor sheet 1 is not present, the dust removing brush B is grounded by the conductive bar 10 and the grounding means 11 to remove the charge, and the dust is removed from the dust removing brush B. By preventing the dust removal brush B from being clogged, the life of the dust brush can be extended. As described above, in the dust removing device K for the stimulable phosphor sheet according to the present embodiment, while preventing the stimulable phosphor sheet 1 from being charged, the dust adhering to and adhering to the surface of the stimulable phosphor sheet 1 is removed. Can be removed. Uncharged, that is, neutral dust can also be removed from the stimulable phosphor sheet 1 by physical contact with the dust removal brush B.

[0013]

In the above embodiment, the stimulable phosphor sheet 1
By using a material having the same or similar charging sequence as that of the dust removal brush B, the stimulable phosphor sheet 1 itself was prevented from being charged. However, in order to more reliably prevent the stimulable phosphor sheet 1 from being charged, By contacting the stimulable phosphor sheet 1 from which dust has been removed with the dust removal brush B with a grounded conductive brush G (shown in FIG. 3), the stimulable phosphor sheet 1 is grounded and charged. It may be removed.
Further, if the grounded conductive brush G is used, the stimulable phosphor sheet 1 itself can be prevented from being charged even if dust is removed by a brush of an arbitrary material (second invention). Such a dust removing device for a stimulable phosphor sheet is also an example of the dust removing device for a stimulable phosphor sheet according to the present invention. In the above embodiment, the material of the antistatic brush b1 and the material of the electrostatic brush b2 are different. However, by providing a large contact area between the antistatic brush b1 and the electrostatic brush b2, the same material can be charged. It is possible to remove dust that has been generated. This is based on the fact that even when the same material is rubbed, charging occurs due to the contact state. Such a dust removing device for a stimulable phosphor sheet is also an example of the dust removing device for a stimulable phosphor sheet according to the present invention.

In the above embodiment, the electrostatic brush b
2. The charged dust is electrostatically adsorbed and separated by using the antistatic brush b1 charged by friction with the dust 2, and the dust is removed from the stimulable phosphor sheet 1. However, an electrostatic field is applied to the charged dust. May remove dust. FIG. 4 shows an example of a dust removing device for a stimulable phosphor sheet that removes charged dust by applying an electrostatic field. As shown in FIG.
The dust removing device for the stimulable phosphor sheet includes a first electric field applying means 41 for applying an electric field to the dust, and a second electric field applying means 4 for applying an electric field having a polarity opposite to that of the first electric field applying means.
And neutral dust removing means 43 for removing neutral dust by blowing air onto the surface of the stimulable phosphor sheet 1. By allowing the stimulable phosphor sheet 1 to pass through the first electric field applying means 41 and the second electric field applying means 42, positive and negative electric fields are alternately applied to dust charged and adhered to the surface of the stimulable phosphor sheet 1. For example, both the positively and negatively charged dust are electrostatically attracted to the electrode 41a or 42a and removed from the stimulable phosphor sheet 1. Also,
Uncharged dust is sucked by the neutral dust removing means 43 and removed from the stimulable phosphor sheet 1. FIG. 5 shows another example of an apparatus for removing charged dust by applying an electric field. In the dust removing device shown in FIG. 5, the electrodes 51a and 51b of the electric field applying means 51 are arranged so as to be shifted by a predetermined amount in the transport direction of the stimulable phosphor sheet 1.
Therefore, the electric field generated by the electric field applying means 51 has a component in the transport direction of the stimulable phosphor sheet 1 and in the direction perpendicular thereto. In the dust removing device, dust charged in the opposite polarity to the electric field is electrostatically attracted to the electrode 51a, and dust charged in the same polarity as the electric field is repelled electrostatically to the surface of the stimulable phosphor sheet 1. And finally the stimulable phosphor sheet 1
Be excluded from. Such a dust removing device for a stimulable phosphor sheet is also an example of the dust removing device for a stimulable phosphor sheet according to the present invention.

[0015]

As described above, the first aspect of the present invention relates to a dust removing apparatus for a stimulable phosphor sheet for removing dust adhering to the surface of a stimulable phosphor sheet for accumulating and recording a radiation image. A stimulable phosphor, comprising: a static eliminator for electrostatically adsorbing and / or separating dust adhering and adhering to the phosphor sheet surface and removing the dust from the stimulable phosphor sheet. It is configured as a sheet dust removing device. As a result, dust that cannot be removed by mechanical operation or air flow can be electrostatically removed from the stimulable phosphor, and the radiation image can be read. Occurrence of white spots, which are sometimes blocked by dust, can be prevented. Therefore, by using the dust removing device for the stimulable phosphor sheet, the reading reliability of the radiation image reading apparatus using the stimulable phosphor sheet is improved.

In order to electrostatically remove dust adhering and adhering to the stimulable phosphor sheet, for example, the static elimination means is provided with a predetermined amount of dust adhering to the surface of the stimulable phosphor sheet and adhering thereto. The first electric field applying means for applying an electric field, and the second electric field applying means for applying an electric field having a polarity opposite to that of the first electric field applying means to the dust can be provided. In this case, by applying an electric field of positive and negative alternately to the dust charged and adhered to the surface of the stimulable phosphor sheet, the dust adhered electrostatically to the stimulable phosphor sheet is adsorbed and the stimulable phosphor sheet is adsorbed. The dust can be removed from the body sheet. In the case where the static elimination means is a dust removing brush which uses the same material as the stimulable phosphor sheet or a material having a similar charging sequence and removes the dust by contacting the stimulable phosphor sheet, Since the dust removing brush in contact with the stimulable phosphor sheet is made of the same material as the stimulable phosphor sheet or a material having a similar charging sequence, the stimulable phosphor sheet itself is charged by friction with the dust removing brush. Can be prevented. Therefore, it is possible to prevent the accumulation phosphor sheet from being easily charged and the dust floating in the air from easily adhering. Also, since the same material can be charged depending on the contact state, the dust removing brush is charged by enlarging the contact area of each of the brushes of the dust removing brush, and the stimulable phosphor sheet is charged. It is possible to remove dust adhering by electrostatically attracting or separating the dust. Of course, neutral dust that is not charged is also removed by contacting the dust removal brush.

Furthermore, if a brush charge removing means for removing the charge of the dust removing brush is provided, when the dust attached to the stimulable phosphor sheet is not removed, the charge of the dust removing brush is grounded, for example. Can be removed. Therefore, the dust adsorbed on the dust removing brush can be removed from the dust removing brush, so that the dust removing brush is prevented from being clogged, and the life of the dust removing brush can be extended. Further, if the handle portion of the dust removing brush is made of a material that is positively and / or negatively charged by rubbing with the dust removing brush, members made of different materials rub against each other. It is easy to be charged and the amount of charge is large, so that dust adhering and adhering to the stimulable phosphor sheet can be easily removed electrostatically. Further, if a sheet charge removing means for removing the charge on the surface of the stimulable phosphor sheet by contacting the stimulable phosphor sheet is provided,
For example, by grounding the stimulable phosphor sheet, it is possible to more reliably prevent the stimulable phosphor sheet from being charged. Therefore, it is possible to prevent the stimulable phosphor sheet from being charged and dust from easily adhering.

According to a second aspect of the present invention, there is provided a dust removing device for a stimulable phosphor sheet for removing dust adhering to the surface of a stimulable phosphor sheet for accumulating and recording a radiation image. A brush for contacting the conductive member, a conductive member for contacting the surface of the stimulable phosphor sheet charged by friction with the brush, and grounding means for grounding the conductive member. It is configured as a dust removing device for the phosphor sheet. By grounding the brush by the conductive member and the grounding means, it is possible to prevent the stimulable phosphor sheet from being charged due to friction with the brush. Further, when the brush is charged, it is possible to remove dust that has been charged and adhered to the surface of the stimulable phosphor sheet.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a dust removing brush according to an embodiment of the present invention.

FIG. 2 is a view for explaining dust removal by the dust removal brush.

FIG. 3 is a diagram showing a schematic configuration of a dust removing device for a stimulable phosphor sheet provided with a conductive brush.

FIG. 4 is a view showing a schematic configuration of a dust removing device for a stimulable phosphor sheet according to an embodiment of the present invention.

FIG. 5 is a view schematically showing a configuration of a dust removing device for a stimulable phosphor sheet according to another embodiment of the present invention.

FIG. 6 is a diagram showing a schematic configuration of a radiation image reading apparatus using a stimulable phosphor sheet.

FIG. 7 is a diagram showing a schematic configuration of a conventional dust removing device for a stimulable phosphor sheet.

FIG. 8 is a diagram showing a schematic configuration of another conventional dust removing device for a stimulable phosphor sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Storable phosphor sheet 2 ... Radiation exposure part 3 ... Excitation light irradiation means 4 ... Photodetector 5 ... Image processing means 6 ... Image reading part 7 ... Conveying means 8 ... Nozzle 9 ... Rotary cleaning roll

Claims (7)

[Claims] 1. A dust removing device for a stimulable phosphor sheet for removing dust adhering to a surface of a stimulable phosphor sheet for accumulating and recording a radiation image, wherein the dust is charged and adhered to the surface of the stimulable phosphor sheet. A dust removing device for the stimulable phosphor sheet, comprising: electrostatic elimination means for electrostatically adsorbing and / or separating the stimulable phosphor from the stimulable phosphor sheet. 2. The first electric field applying means for applying a predetermined electric field to dust adhered to the surface of the stimulable phosphor sheet by charging the static electricity removing means, and the first electric field applying means is opposite to the first electric field applying means. 2. The dust removing device for a stimulable phosphor sheet according to claim 1, further comprising second electric field applying means for applying a polar electric field to said dust. 3. The method according to claim 2, wherein the static elimination means is made of the same material as the stimulable phosphor sheet or a material having a similar charging sequence.
2. The dust removing device for a stimulable phosphor sheet according to claim 1, wherein the dust removing brush removes the dust by contacting the stimulable phosphor sheet. 4. The dust removal of a stimulable phosphor sheet according to claim 3, wherein the handle portion of the dust removal brush is made of a material that is positively and / or negatively charged by friction with the dust removal brush. apparatus. 5. An apparatus for removing dust from a stimulable phosphor sheet according to claim 3, further comprising brush charge removing means for removing the charge of said dust removing brush. 6. The stimulable phosphor sheet according to claim 3, further comprising a sheet charge removing means for contacting the stimulable phosphor sheet to remove the charge on the surface of the stimulable phosphor sheet. Dust removal device. 7. A dust removing device for a stimulable phosphor sheet for removing dust adhering to a surface of a stimulable phosphor sheet for accumulating and recording a radiation image, comprising: a brush contacting the surface of the stimulable phosphor sheet; A dust removing device for a stimulable phosphor sheet, comprising: a conductive member in contact with the surface of the stimulable phosphor sheet charged by friction with a brush; and a grounding means for grounding the conductive member. apparatus.