JP2005073023A - Image reading apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus and an image forming apparatus capable of providing a high definition image by a small and inexpensive apparatus constitution. <P>SOLUTION: The image reading apparatus for moving a stimulable phosphor sheet 14 with an image recorded thereon to a reading section 32 for reading the image recorded on the stimulable phosphor sheet 14 to read the image is provided with a linear motor consisting of a magnet section 23 and a movable coil 25 and for straightly moving the stimulable phosphor sheet 14, wherein the magnet section 23 is formed into a shaft-like style extended in a moving direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image reading apparatus and an image forming apparatus, and more particularly to an image reading apparatus and an image forming apparatus using a linear motor as a driving source for main scanning or sub scanning in image reading processing or image forming processing.

  In general, in various fields, for example, image reading for reading an image by transporting the recording medium in a sub-scanning direction orthogonal to the main scanning direction while scanning a laser beam in the main scanning direction with respect to the recording medium on which the image is recorded. An image is formed by conveying the recording medium in a sub-scanning direction orthogonal to the main scanning direction while the apparatus or, for example, a laser beam irradiation device scans the recording medium in the main scanning direction based on predetermined image data. An image forming apparatus is used.

  In particular, in the medical field, radiographic images are widely used for disease diagnosis and the like. As a method for obtaining such radiographic images, radiation transmitted through a subject is accumulated and recorded in a stimulable phosphor sheet. After that, the radiation energy stored and recorded by irradiating the excitation light with the image reading device is stimulated to emit light, the intensity of this stimulated emission light is converted into an electric signal, and the image forming device is based on this electric signal. A visible image is formed on a recording medium.

  As described above, the image reading apparatus and the image forming apparatus used in the medical field are required to obtain a high-definition image particularly from the viewpoint of diagnosing a disease based on the obtained image. In order to obtain a high-definition image, it is necessary to scan the recording medium and the laser beam irradiation device accurately and smoothly. For this reason, as a drive source for linear movement of the recording medium and the laser beam irradiation device in recent years, It has been proposed to use a linear motor.

  As an image forming apparatus using a linear motor as a scanning drive source of a laser beam irradiation apparatus, a cylindrical support drum that supports and rotates a recording medium, and is provided to face the support drum. 2. Description of the Related Art An image forming apparatus that includes a laser light irradiation device that irradiates laser light based on predetermined image data while reciprocating in the width direction and includes a linear motor that moves the laser light irradiation device is known ( For example, see Patent Document 1).

This image forming apparatus has a holding portion for holding a laser beam irradiation device, and below this holding portion, a U-shaped magnet portion constituting a linear motor opens to one side. The recording medium is provided so as to extend in a direction perpendicular to the conveyance direction of the recording medium. In addition, on the lower surface of the holding portion, a movable coil having a L-shaped cross section that forms a linear motor and hangs down from the lower surface of the holding portion and extends in the horizontal direction sandwiches the upper and lower surfaces of the horizontal portion between the openings of the magnet portion. Is provided. As a result, the laser beam irradiation apparatus scans the recording medium with the laser beam while moving with the reciprocal movement of the holding unit by the linear motor.
JP-A-11-216921

  However, in the image forming apparatus as described above, when the horizontal portion and the vertical portion of the movable coil are not sufficiently rigid, the holding portion is delayed from the conveyance speed of the linear motor, or vibration is generated, resulting in smoothness. As a result, the laser beam irradiation apparatus holding the holding unit may shift the position of the laser beam applied to the recording medium, resulting in image unevenness. Therefore, in order to obtain a good image, it is necessary to increase the rigidity of the moving coil. As a result, the moving coil requires a certain size or more, and there is a limit to downsizing and cost reduction of the apparatus. was there.

  In addition, in a linear motor having a U-shaped magnet, the use efficiency of the magnetic flux is poor, and in order to obtain a large thrust, the magnetic flux density must be increased, resulting in an increase in the size of the magnet. For this reason, there was a limit to miniaturization and cost reduction of the apparatus.

  SUMMARY An advantage of some aspects of the invention is that it provides an image reading apparatus and an image forming apparatus that can obtain a high-definition image with a small and low-cost apparatus configuration.

  In order to solve the above-described problems, an image reading apparatus according to the present invention moves a moving object composed of one of a recording medium on which an image is recorded and a reading unit that reads the image recorded on the recording medium with respect to the other. In the image reading apparatus for reading an image, a linear motor configured by a magnet part and a movable coil is provided to linearly move the moving object, and the magnet part is formed in a shaft shape extending in the moving direction. And

  According to the first aspect of the present invention, since the magnet portion is in the shape of a shaft, it is only necessary to cover the peripheral surface of the shaft-shaped magnet portion with the movable coil, and the movable coil has a shape that is easy to obtain rigidity. For this reason, it is possible to prevent the movement speed from being delayed with respect to the conveyance speed of the linear motor without enlarging the movable coil more than necessary, and the recording medium or the reading unit can be smoothly conveyed without generating vibration. The

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. .

  According to a second aspect of the present invention, in the image reading apparatus according to the first aspect of the present invention, a guide portion that guides the straight movement of the moving object is provided.

  According to the second aspect of the present invention, since the guide unit that guides the straight movement of the moving object is provided, the recording medium or the reading unit that is the moving object is stably conveyed.

  According to a third aspect of the present invention, in the image reading apparatus according to the second aspect, the guide section is single.

  According to the invention described in claim 3, it is possible to further reduce the size and cost of the entire apparatus.

  According to a fourth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the moving direction is a vertical direction.

  According to the fourth aspect of the present invention, even if the moving direction is the vertical direction, it is possible to prevent the moving speed from being delayed with respect to the linear motor conveying speed without making the movable coil larger than necessary. The recording medium or the reading unit is smoothly conveyed without vibration.

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. .

  According to a fifth aspect of the present invention, in the image reading device according to the fourth aspect of the present invention, a moving body that holds and moves the moving object and a counterweight that balances the moving body are provided, and the moving body A connecting member for connecting the counterweight is provided, the moving body moves linearly by the linear motor, and the counterweight moves relative to the moving body.

  According to the fifth aspect of the present invention, when the moving body is raised by the linear motor, the counterweight falls by its own weight, so that the thrust by the linear motor can be reduced.

  A sixth aspect of the present invention is the image reading apparatus according to the fifth aspect, further comprising a brake mechanism that prevents the moving body or the counterweight from falling by its own weight when the driving of the linear motor is stopped. And

  According to the sixth aspect of the present invention, it is possible to prevent the moving body or the counterweight from falling due to its own weight when the driving of the linear motor is stopped.

  An image forming apparatus according to claim 7 forms an image by moving a moving object composed of either one of a recording medium and a recording unit for recording an image on the recording medium with respect to the other. In the present invention, a linear motor that includes a magnet portion and a movable coil and moves the moving object linearly is provided, and the magnet portion is formed in a shaft shape extending in the moving direction.

  According to the seventh aspect of the present invention, since the magnet portion has a shaft shape, it is only necessary to cover the peripheral surface of the shaft-shaped magnet portion with the movable coil, and the movable coil has a shape in which rigidity is easily obtained. Therefore, it is possible to prevent the moving body from being delayed with respect to the conveyance speed of the linear motor without enlarging the moving coil more than necessary, and the recording medium or the recording unit can be smoothly conveyed without generating vibration. The

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. .

  According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect of the present invention, a guide portion that guides the straight movement of the moving object is provided.

  According to the eighth aspect of the present invention, since the guide portion that guides the straight movement of the moving object is provided, the recording medium or the recording portion that is the moving object is stably conveyed.

  According to a ninth aspect of the present invention, in the image forming apparatus according to the eighth aspect of the present invention, the guide section is single.

  According to the invention described in claim 9, it is possible to further reduce the size and cost of the entire apparatus.

  According to a tenth aspect of the present invention, in the image forming apparatus according to any one of the seventh to ninth aspects, the moving direction is a vertical direction.

  According to the tenth aspect of the present invention, even when the moving direction is the vertical direction, it is possible to prevent the moving body from being delayed with respect to the conveying speed of the linear motor without increasing the moving coil more than necessary. The recording medium or the recording unit is smoothly conveyed without vibration.

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. .

  According to an eleventh aspect of the present invention, in the image forming apparatus according to the tenth aspect of the present invention, a moving body that holds and moves the moving object and a counterweight that balances the moving body are provided. A connecting member for connecting the counterweight is provided, the moving body moves linearly by the linear motor, and the counterweight moves relative to the moving body.

  According to the eleventh aspect of the present invention, since the counterweight falls by its own weight when the moving body is raised by the linear motor, the thrust by the linear motor can be reduced.

  According to a twelfth aspect of the present invention, in the image forming apparatus according to the eleventh aspect of the present invention, the image forming apparatus further includes a brake mechanism that prevents the movable body or the counterweight from falling by its own weight when the driving of the linear motor is stopped. And

  According to the twelfth aspect of the present invention, it is possible to prevent the moving body or the counterweight from falling due to its own weight when the driving of the linear motor is stopped.

  According to the first aspect of the present invention, the movable coil is fixed in the apparatus so that rigidity is easily obtained, and the moving speed is increased with respect to the conveying speed of the linear motor without making the movable coil larger than necessary. Is prevented, and the recording medium or the reading unit is smoothly transported without generating vibration. Therefore, a high-definition image can be obtained with a small and low-cost apparatus configuration.

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. Therefore, it is possible to reduce the size and cost of the apparatus.

  According to the second aspect of the present invention, the guide unit that guides the moving object is provided, and the recording medium or the reading unit that is the moving object is more smoothly conveyed, so that a higher-definition image can be obtained. Can be obtained.

  According to the third aspect of the present invention, since the guide portion is singular, the entire apparatus can be further reduced in size and cost.

  According to the fourth aspect of the present invention, even if the moving direction is the vertical direction, it is possible to prevent the moving speed from being delayed with respect to the linear motor conveying speed without making the movable coil larger than necessary. Since the recording medium or the reading unit is smoothly conveyed without vibration, a high-definition image can be obtained with a small and low-cost apparatus configuration.

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. Therefore, it is possible to reduce the size and cost of the apparatus.

  According to the invention described in claim 5, since the counterweight falls by its own weight when the moving body is raised by the linear motor, the thrust by the linear motor can be reduced. Can be downsized, and as a result, downsizing and cost reduction of the apparatus can be achieved.

  According to the sixth aspect of the present invention, it is possible to prevent the moving body or the counterweight from falling due to its own weight when the driving of the linear motor is stopped.

  According to the seventh aspect of the present invention, the movable coil is fixed in the apparatus so that it is easy to obtain rigidity, and the moving speed is increased with respect to the conveying speed of the linear motor without making the movable coil larger than necessary. Is prevented, and the recording medium or the recording unit is smoothly conveyed without generating vibrations. Therefore, a high-definition image can be obtained with a small and low-cost apparatus configuration.

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. Therefore, it is possible to reduce the size and cost of the apparatus.

  According to the eighth aspect of the present invention, since the guide portion for guiding the straight movement of the moving object is provided, and the recording medium or the recording portion that is the moving object is transported more smoothly, higher definition is achieved. Can be obtained.

  According to the ninth aspect of the present invention, since the guide portion is singular, it is possible to further reduce the size and cost of the entire apparatus.

  According to the tenth aspect of the present invention, even when the moving direction is the vertical direction, the moving speed is prevented from being delayed with respect to the conveying speed of the linear motor without increasing the moving coil more than necessary. Since the recording medium or the recording unit is smoothly conveyed without vibration, a high-definition image can be obtained with a small and low-cost apparatus configuration.

  In addition, if the peripheral surface of the shaft-shaped magnet part is covered with a movable coil, the magnetic flux can be used efficiently, and even when it is desired to obtain a large thrust, it is not necessary to increase the size of the magnet part more than necessary. Therefore, it is possible to reduce the size and cost of the apparatus.

  According to the eleventh aspect of the invention, since the counterweight falls by its own weight when the moving body is raised by the linear motor, the thrust by the linear motor can be reduced. Can be downsized, and as a result, downsizing and cost reduction of the apparatus can be achieved.

  According to the twelfth aspect of the present invention, it is possible to prevent the moving body or the counterweight from falling due to its own weight when the driving of the linear motor is stopped.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3.

  FIG. 1 shows an embodiment of an image reading apparatus 1 according to the present invention, and a photostimulable phosphor sheet as a recording medium on which an image is recorded is provided on the upper part on the front side of the image reading apparatus 1. An insertion port 3 for inserting a cassette 2 containing 14 is provided, and a feed roller 4 for feeding the cassette 2 into the image reading apparatus 1 is provided at the lower end of the insertion port 3.

  At the upper part on the front side of the image reading apparatus 1 and behind the insertion port 3, an outlet 5 for taking out the cassette 2 subjected to the reading process is provided, and at the lower end portion of the outlet 5, the cassette 2 is provided. A delivery roller 6 that feeds the image reading apparatus 1 to the outside is provided.

  A cassette conveying device 7 that conveys the cassette 2 to a predetermined position is provided at the lower part on the front side of the image reading device 1 so as to be rotatable by a driving mechanism (not shown) with the lower end serving as a support shaft. The position a, the position b corresponding to the outlet 5, and the position c where the cassette 2 is substantially vertical can be stopped.

  The cassette transport device 7 has a box-shaped cassette support portion 8 whose upper surface and back surface are open, and an elevator base 9 that can move up and down while supporting the lower end portion of the cassette 2 inside the cassette support portion 8. Is provided.

  Further, inside the cassette support portion 8, the cassette 2 can be separated into a back plate 10 that holds the stimulable phosphor sheet 14 from the back and a front plate 11 that covers the surface of the stimulable phosphor sheet 14. An unlocking mechanism (not shown) is provided. As the lock release mechanism, for example, a lock release mechanism disclosed in JP-A-2002-278000 can be used.

  A plate-like support member 13 extending in the vertical direction from the base 12 is provided on the back side of the image reading apparatus 1, and a photostimulable phosphor sheet 14 is held on the support member 13. A movable body 15 movable in the vertical direction by a linear motor and a counterweight 16 that balances the movable body 15 are supported via a connecting member 17 so as to be relatively movable up and down. A first guide rail 18 serving as a guide portion for guiding the moving body 15 in the vertical direction is provided at the substantially front center of the support member 13, and a first guide rail 18 for guiding the counterweight 16 in the vertical direction is provided on the back surface. Two guide rails 19 are provided.

  As shown in FIGS. 1 to 3, the moving body 15 has a plate-like holding portion 20 that holds the back plate 10 of the cassette 2 that supports the photostimulable phosphor sheet 14. A rubber magnet is provided on the surface of the holding portion 20, and the back plate 10 of the cassette 2 is configured by attaching a ferromagnetic sheet to a main body formed of a synthetic resin. The back plate 10 is adhered to the holding portion 20 by a magnetic force and is held.

  A mounting member 21 is provided on the back surface of the holding portion 20, and a first cover having a U-shaped cross section guided by the first guide rail 18 is provided on a surface of the mounting member 21 that faces the holding portion mounting surface. A guide member 22 is provided integrally with the attachment member 21.

  On one side of the attachment member 21, a magnet portion 23 that constitutes a linear motor is supported by a support piece 24 formed integrally with the support member 13 and extends in the vertical direction. The magnet portion 23 is formed in a shaft shape by connecting a plurality of N poles or S poles of a permanent magnet having a circular cross section.

  On the other hand, a movable coil 25 constituting a linear motor is provided on the side of the mounting member 21. This movable coil 25 has a coil formed in a cylindrical shape, and this coil is covered with a box-shaped cover member. And the linear motor is comprised so that the magnet part 23 may penetrate the center of the movable coil 25.

  On the front side of the support member 13 and on the opposite side of the first guide rail 18 from the magnet unit 23, a linear scale 26 constituting an encoder for detecting the position and moving speed of the moving body 15 is provided in the vertical direction. It is provided to extend. A sensor unit 27 that constitutes an encoder and reads the linear scale 26 is provided at a position facing the linear scale 26 of the holding unit 20.

  The counterweight 16 has a second guided member 37 having a U-shaped cross section guided by the second guide rail 19.

  A first pulley 28 is provided on the front side above the support member 13, and a second pulley 29 and a third pulley 30 are provided vertically on the back side. A belt-like connecting member 17 is passed to the pulleys 28, 29, and 30. A moving body 15 is fastened to the front side end of the connecting member 17, and a counterweight 16 is attached to the back side end. Is concluded. A steel wire can also be used as the connecting member 17.

  The moving body 15 is a member that can move with respect to the magnet portion 23, and in the present embodiment, is configured by the movable coil 25, the holding portion 20, the attachment member 21, and the first guided member 22.

  Further, a brake mechanism 31 such as a torque limiter, a one-way clutch, an electromagnetic brake, or the like that stops the rotation operation of the first pulley 28 is provided on the shaft portion of the first pulley 28.

  A reading unit 32 for reading the radiation energy stored and recorded in the photostimulable phosphor sheet 14 held by the holding unit 20 is provided at a position above the movable range of the moving body 15 and facing the moving body 15. It has been.

  The reading unit 32 irradiates the stimulable phosphor sheet 14 while scanning the laser beam L1 in a direction orthogonal to the moving direction of the moving body 15, and the laser beam irradiating device 33 causes the laser beam irradiating device 33 to radiate light. The light guide plate 34 that guides the stimulated emission light L2 that is excited by irradiating the light-emitting phosphor sheet 14 with the laser light L1, and the light collection tube 35 that collects the stimulated emission light L2 guided by the light guide plate 34. And a photoelectric converter 38 for converting the photostimulated light L2 collected by the condenser 35 into an electrical signal.

  Below the reading unit 32, after the radiation energy is read by the reading unit 32, the photostimulable phosphor sheet 14 is erased to release the radiation energy remaining in the photostimulable phosphor sheet 14. An erasing device 36 for irradiating light is provided.

  Next, the operation of this embodiment will be described.

  When performing the image reading process, the cassette carrying device 7 is put on standby at a position a corresponding to the insertion port 3, and in this state, the photostimulable phosphor sheet 14 on which the radiation image is recorded is stored from the insertion port 3. When the cassette 2 is inserted, the cassette 2 is fed into the cassette transport device 7 by the feeding roller 4. Then, the elevator 9 is lowered while supporting the lower end portion of the cassette 2, the cassette 2 is accommodated in the cassette transport device 7, and the lock release mechanism is activated, so that the cassette 2 and the front plate 11 are excited. It will be in the state which can be isolate | separated into the back board 10 holding the fluorescent substance sheet 14. FIG.

  Thereafter, the cassette carrying device 7 is moved to a position c where the cassette 2 is substantially vertical. At this time, the movable body 15 is positioned at the lowermost end of the movable range, so that the holding portion 20 and the back plate 10 of the cassette 2 face each other, and the back that supports the photostimulable phosphor sheet 14 by magnetic force. The plate 10 is adsorbed by the holding unit 20 and is held by the holding unit 20 in a state where it is separated from the front plate 11 and the surface of the photostimulable phosphor sheet 14 is exposed. The cassette conveying device 7 may be retracted to a position b corresponding to the outlet 5 while the front plate 11 is held.

  Thereafter, the linear motor is driven to raise the moving body 15 along the first guide rail 18. As a result, the photostimulable phosphor sheet 14 is conveyed to a position facing the reading unit 32, and the laser beam L1 is scanned by the laser beam irradiation device 33. The light is guided by 34 and condensed on the condenser tube 35, and is converted into an electric signal by the photoelectric converter 38.

  Here, since the magnet portion 23 is formed in a shaft shape, the movable coil 25 has a shape in which a coil formed in a cylindrical shape is covered with a box-shaped cover member, and is fixed to the holding portion 20. It has a highly rigid shape. Therefore, it is possible to prevent the moving body 15 from being delayed with respect to the conveying speed of the linear motor without increasing the moving coil more than necessary, and the photostimulable phosphor sheet 14 can be smoothly produced without generating vibration. Be transported. Moreover, since the pulleys 28, 29, and 30 rotate as the moving body 15 rises and the counterweight 16 falls by its own weight along the second guide rail 19, the thrust by the linear motor can be reduced. It becomes possible to reduce the size of the magnet part and the movable coil.

  When the reading process by the reading unit 32 is completed up to the lower end of the photostimulable phosphor sheet 14, the linear motor is stopped. At this time, the rotation of the first pulley 28 is stopped by the brake mechanism 31, and the moving body 15 stops in a stable state.

  Thereafter, the linear motor is driven again, and the moving body 15 is lowered along the first guide rail 18, and at the same time, the erasing device 36 irradiates the stimulable phosphor sheet 14 with erasing light, The radiation image remaining on the photostimulable phosphor sheet 14 is erased.

  Then, when the moving body 15 descends to the lowest end of the movable range and stops, the cassette carrying device 7 is rotated to a position c where the cassette 2 is substantially vertical. As a result, the back plate 10 and the front plate 11 are locked together.

  And while rotating the cassette conveying apparatus 7 to the position b corresponding to the exit 5 with the drive mechanism which is not shown in figure, the cassette 2 is pulled away from the holding | maintenance part 20, the raising / lowering stand 9 is raised, and the sending roller 6 is operated. Thus, the cassette 2 is taken out from the outlet 5.

  As described above, according to the present embodiment, the shape is easy to obtain rigidity when the movable coil 25 is fixed to the holding unit 20, and the linear motor can be transported at a speed higher than necessary without making the movable coil 25 larger than necessary. Since the moving body 15 is prevented from being delayed and the recording medium or the recording unit is smoothly conveyed without generating vibration, a high-definition image can be obtained with a small and low-cost apparatus configuration. .

  In addition, since the shaft-shaped magnet portion 23 penetrates the movable coil 25 formed in a cylindrical shape, the use efficiency of the magnetic flux is good, and even when it is desired to obtain a large thrust, the size of the magnet portion 23 is reduced. Since it is not necessary to make it larger than necessary, the apparatus can be reduced in size and cost.

  Furthermore, when the moving body 15 is raised by the linear motor, the counterweight 16 falls by its own weight, so that the thrust by the linear motor can be reduced. Therefore, the magnet portion 23 and the movable coil 25 can be downsized. As a result, the apparatus can be reduced in size and cost.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 4 shows an embodiment of the image forming apparatus 40 according to the present invention. In the image forming apparatus 40, a storage tray 42 for storing a plurality of recording media 41 is provided. A take-out device 43 for taking out the recording medium 41 on which an image is to be recorded from the accommodation tray 42 one by one is provided above one end of the accommodation tray 42.

  The recording medium 41 is formed of a first sheet having a color material layer and a second sheet having a base layer, and the material is ablated between the color material layer and the base layer by irradiating laser light. A recording medium 41 that can generate an image by transferring the color material layer to the second sheet is applied.

  A cylindrical support drum 44 that supports the recording medium 41 is rotatably disposed below the storage tray 42, and the support drum 44 is rotated by a drum driving mechanism. Yes. Further, on the peripheral surface of the support drum 44, a gripper 45 a that grips the front end portion of the recording medium 41 over the entire width and a gripper 45 b that grips the rear end portion of the recording medium 41 over the entire width extend in the axial direction of the support drum 44. Is provided.

  On the side of the support drum 44, a driven roller 46 slidably contacting the support drum 44 and driven to rotate is provided so as to be able to contact and separate from the support drum 44.

  A discharge tray 47 for discharging the recording medium 41 on which an image is recorded is provided on the upper part of the image forming apparatus 40.

  Inside the image forming apparatus 40, the recording medium 41 supplied from the storage tray 42 is conveyed to the upper peripheral surface of the support drum 44, and after the recording medium 41 is conveyed along the peripheral surface of the support drum 44, A conveyance path is provided for discharging from the upper peripheral surface of the support drum 44 to the discharge tray 47. Plural pairs of transport rollers 48 for transporting the recording medium 41 in the transport direction are provided at predetermined positions on the transport path.

  A laser beam irradiation device 49 as a recording unit for irradiating the recording medium 41 supported by the support drum 44 with laser light is provided on the side of the peripheral surface of the support drum 44. A moving body 50 that holds the laser beam irradiation device 49 and can be reciprocated in a direction orthogonal to the conveyance direction of the recording medium 41 by a linear motor is provided in the lower part.

  A plate-like support member 51 extending in a direction orthogonal to the conveyance direction of the recording medium 41 is provided below the moving body 50, and the width of the recording medium 41 is approximately at the center of the upper surface of the support member 51. A guide rail 52 is provided as a guide portion for guiding the moving body 50 in the direction.

  The moving body 50 has a plate-like holding portion 53 that holds the laser beam irradiation device 49. A mounting member 54 is provided on the back surface of the holding portion 53, and a guided member 55 having a U-shaped cross section guided by the guide rail 52 is provided on a surface of the mounting member 54 that faces the holding portion mounting surface. Is provided integrally with the mounting member 54.

  On one side of the mounting member 54, a magnet portion 56 constituting a linear motor is supported by a support piece 57 formed integrally with the support member 51 and extends in a direction perpendicular to the conveyance direction of the recording medium 41. It has been. The magnet portion 56 is formed in a shaft shape by connecting a plurality of N poles or S poles of a permanent magnet having a circular cross section.

  On the other hand, a movable coil 58 constituting a linear motor is provided on the side of the mounting member 54. The movable coil 58 has a coil formed in a cylindrical shape, and this coil is covered with a box-shaped cover member. The linear motor is configured such that the magnet portion 56 passes through the center of the movable coil 58.

  On the upper surface of the support member 51 and on the opposite side of the guide rail 52 from the magnet portion 56, a linear scale 59 constituting an encoder for detecting the position and moving speed of the moving body 50 is provided on the recording medium 41. Extending in the width direction. A sensor unit 60 that constitutes an encoder and reads the linear scale 59 is provided at a position of the holding unit 53 facing the linear scale 59.

  A peeling device 61 for peeling the first sheet and the second sheet of the recording medium 41 exposed by the laser beam irradiation device 49 is provided on the downstream side of the conveyance path from the support drum 44, below the discharge tray 47. Is provided with a collecting roll 62 that winds and collects the first sheet peeled from the second sheet by the peeling device 61. Further, a discharge roller 63 for discharging the second sheet on which the image is formed to the discharge tray 47 is provided on the downstream side of the conveying path from the peeling device 61.

  Next, the operation of this embodiment will be described.

  When the image information is sent to the image forming apparatus 40, the take-out device 43 is operated to take out the uppermost recording medium 41 stored in the storage tray 42, and the transport roller 48 is rotated so that the taken-out recording is performed. The medium 41 is conveyed.

  When the recording medium 41 reaches the vicinity of the upper peripheral surface of the support drum 44, the support drum 44 rotates clockwise in FIG. 4 with the gripper 45a gripping the front end portion of the recording medium 41 by the drum driving mechanism. When the gripper 45 a passes the position of the driven roller 46 with the rotation of the support drum 44, the driven roller 46 comes into contact with the support drum 44 and holds the recording medium 41 on the peripheral surface of the support drum 44. When the gripper 45 b moves to the position of the rear end portion of the recording medium 41 with the rotation of the support drum 44 and grips the rear end portion of the recording medium 41, the driven roller 46 is separated from the support drum 44.

  Thereafter, the support drum 44 rotates in a direction opposite to the clockwise direction in FIG. 4, and when the recording medium 41 is sent to the position of the laser beam irradiation device 49 as the support drum 44 rotates, the laser beam irradiation device 49 causes an image Based on the information, the recording medium 41 is irradiated with laser light. At this time, the laser beam irradiation device 49 scans the recording medium 41 with the laser beam as the moving body 50 reciprocates in the direction orthogonal to the conveyance direction of the recording medium 41 by driving the linear motor.

  Here, since the magnet portion 56 is formed in a shaft shape, the movable coil 58 has a shape in which a coil formed in a cylindrical shape is covered with a box-shaped cover member, and is fixed to the holding portion 53. It has a highly rigid shape. Therefore, without making the movable coil 58 larger than necessary, it is possible to prevent the moving body 50 from being delayed with respect to the conveying speed of the linear motor, and the laser beam irradiation device 49 can smoothly scan without generating vibration. Is done.

  When the laser light irradiation by the laser light irradiation device 49 is completed, the recording medium 41 is transported along the transport path by the transport roller 48.

  When the recording medium 41 is conveyed to the position of the peeling device 61, it is peeled off by the peeling device 61 into the first sheet and the second sheet. Then, the first sheet is collected by the collection roll 62, and the second sheet is discharged to the discharge tray 47 by the transport roller 48 and the discharge roller 63.

  As described above, according to the present embodiment, the movable coil 58 is fixed to the holding portion 53 so that it is easy to obtain rigidity, and the moving speed of the linear motor can be increased without increasing the movable coil 58 more than necessary. Since the moving body 50 is prevented from being delayed and the laser beam irradiation device 49 is smoothly conveyed without vibration, a high-definition image can be obtained with a small and low-cost device configuration. .

  In addition, since the shaft-shaped magnet portion 56 penetrates the movable coil 58 formed in a cylindrical shape, the use efficiency of the magnetic flux is good, and even when it is desired to obtain a large thrust, the size of the magnet portion 56 is reduced. Since it is not necessary to make it larger than necessary, the apparatus can be reduced in size and cost.

It is a figure which shows the structure of one Embodiment of the image reading apparatus by this invention. It is a perspective view which shows the conveyance mechanism of a linear motor part. It is a top view which shows the conveyance mechanism of a linear motor part. 1 is a diagram illustrating a configuration of an embodiment of an image forming apparatus according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image reader 2 Cassette 14 Stimulable phosphor sheet (recording medium)
15 Moving body 16 Counterweight 17 Connecting member 18 First guide rail (guide portion)
19 Second guide rail 20 Holding section 23 Magnet section 25 Moving coil 31 Brake mechanism 32 Reading section 40 Image forming apparatus 41 Recording medium 44 Support drum 49 Laser beam irradiation apparatus (recording section)
50 Moving object 52 Guide rail (guide part)
53 Holding part 56 Magnet part 58 Moving coil

Claims (12)

  In an image reading apparatus for reading an image by moving a moving object composed of either a recording medium on which an image is recorded and a reading unit for reading the image recorded on the recording medium with respect to the other, a magnet unit and a movable coil An image reading apparatus comprising: a linear motor configured to linearly move the object to be moved, and the magnet portion formed in a shaft shape extending in a moving direction.   The image reading apparatus according to claim 1, further comprising a guide unit that guides a straight movement of the moving object.   The image reading apparatus according to claim 2, wherein the guide unit is singular.   The image reading apparatus according to claim 1, wherein the moving direction is a vertical direction.   A moving body that holds and moves the moving object and a counterweight that balances the moving body are provided, and a connecting member that connects the moving body and the counterweight is provided, and the moving body is the linear motor The image reading apparatus according to claim 4, wherein the counterweight moves linearly and the counterweight moves relative to the moving body.   The image reading apparatus according to claim 5, further comprising a brake mechanism that prevents the moving body or the counterweight from falling by its own weight when driving of the linear motor is stopped.   In an image forming apparatus that forms an image by moving a moving object composed of either a recording medium or a recording unit that records an image on the recording medium with respect to the other, the moving unit includes a magnet unit and a movable coil. An image forming apparatus comprising a linear motor for moving an object in a straight line and forming the magnet portion in a shaft shape extending in a moving direction.   The image forming apparatus according to claim 7, further comprising a guide unit that guides the straight movement of the moving object.   The image forming apparatus according to claim 8, wherein the guide unit is single.   The image forming apparatus according to claim 7, wherein the moving direction is a vertical direction.   A moving body that holds and moves the moving object and a counterweight that balances the moving body are provided, and a connecting member that connects the moving body and the counterweight is provided, and the moving body is the linear motor The image forming apparatus according to claim 9, wherein the counterweight moves linearly and the counterweight moves relative to the moving body.   The image forming apparatus according to claim 11, further comprising a brake mechanism that prevents the moving body or the counterweight from falling under its own weight when driving of the linear motor is stopped.

Images