JP2011239448A - Image reading apparatus and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reading apparatus and an image forming apparatus that prevent a rise in temperature of light emitting elements by facilitating efficient heat radiation from the light emitting elements with a simple configuration while preventing an increase in manufacturing cost or weight and that allow high-precision image reading.SOLUTION: A copying machine 10 includes: a light irradiator 50 which is provided with a plurality of light emitting diodes 43 arranged along a main original-scanning direction for irradiating an original with light and a circuit board 51 for activating the light emitting diodes 43; a support member 52 on which the light irradiator 50 is mounted; a first mirror 44a for reflecting light that is emitted to an original from the light emitting diodes 43 and reflected from the original, back toward an imaging element 57; and a first carriage 35 on which the support member 52 and the first mirror 44a are mounted and which travels in a sub original-scanning direction. The support member 52 has through-holes 59 formed so as to open in the same direction as a travel direction of the first carriage 35.

Description

  The present invention relates to an image reading apparatus and an image reading apparatus, and for example, an image reading apparatus such as a scanner apparatus provided with a light emitting element that irradiates light to read an original, a facsimile apparatus including the image reading apparatus, and a copying machine The present invention relates to an image forming apparatus such as a multifunction peripheral or a multifunction peripheral.

  In general, in an image reading apparatus such as a facsimile machine, a copier, or a multifunction machine, light is emitted from a light source to a document, and reflected light from the document is folded by a plurality of mirrors and incident on an image sensor such as a CCD image sensor. Like to do.

  In such an image reading apparatus, there are demands for the rise speed of the light source, energy saving, long life, etc. Recently, light emitting elements such as light emitting diodes are arranged in an array instead of a xenon lamp. There is a tendency to adopt a light source.

  In order to improve the productivity (number of copies, etc.), it is necessary to increase the illuminance of the light emitting diode. To increase the illuminance of the light emitting diode, a large current is passed through the light emitting diode or the light emitting diode. Therefore, it is necessary to take measures such as increasing the integration density.

  On the other hand, when the illuminance of the light emitting diode is increased, the light emitting diode generates heat. Therefore, it is indispensable to take measures against heat dissipation as a failure resistance, and suppress the decrease in illuminance and chromaticity change of the light emitting element due to heat generation Therefore, a device for efficiently dissipating and cooling the light emitting diode has been devised.

  As a conventional heat dissipation method for a light source, a plurality of LED chips, which are light emitting elements, are installed in the main scanning direction, a circuit board is placed on a support member, and the support member is placed on a traveling body to perform sub-scanning of a document. There is one in which a support member to which heat is transmitted from an LED chip is air-cooled by traveling in a direction (see, for example, Patent Document 1).

  However, in such a heat-dissipating method by air cooling, since the device for efficiently supplying air to the support member has not been made, it is not possible to dissipate the heat-dissipating member to which heat is transmitted from the LED chip. Cannot be cooled efficiently.

As a heat dissipation method for solving such a problem, a heat dissipation substrate in which a light emitting element array is arranged, and a heat pipe that is positioned substantially parallel to the arrangement direction of a large number of array elements in the light emitting element array and embedded in the heat dissipation substrate In addition, there is a cooling device for a light emitting element array that includes heat dissipating fins arranged at at least one end of the heat pipe (for example, see Patent Document 2).
In addition, by providing a recess in the vicinity of the housing that houses the LED lighting, inside the outer shape of the housing, it serves as a heat radiating fin and suppresses the temperature rise of the unit due to the heat generated by the light emission of the LED lighting light source. There are some (see, for example, Patent Document 3).

  However, in the heat radiation method of the light source shown in Patent Document 2, since it is necessary to provide a heat pipe and a heat radiation fin, the heat pipe and the heat radiation fin are attached to a traveling body that travels the light emitting element array in the sub-scanning direction of the document. In the case of mounting, it is difficult in terms of space, and there is a problem that the weight of the traveling body increases and the load during traveling increases. Furthermore, since the number of parts increases, the manufacturing cost of the image reading apparatus increases.

  Moreover, what is shown in patent document 3 is what only provides a recessed part in a housing, Comprising: It becomes a thing which increased the surface area for heat dissipation, and cannot anticipate the big heat dissipation effect.

  On the other hand, in Patent Document 1, the circuit board provided with the LED chip is attached to the support member with a bolt or the like, but there is no gap in the fastening part with the bolt on the mounting surface of the circuit board and the LED chip. A minute gap is formed in the fastening portion separated from the bolt.

  For this reason, the distribution of heat transmitted from the LED chip to the support member is not constant, and uneven illuminance is caused by the LED chip that becomes high temperature and the LED chip that promotes heat dissipation, and the reading performance deteriorates. There was a problem that.

  The present invention has been made to solve the conventional problems, and efficiently dissipates heat from the light-emitting element with a simple configuration, thereby suppressing an increase in manufacturing cost and weight and suppressing an increase in temperature of the light-emitting element. An object of the present invention is to provide an image reading apparatus and an image forming apparatus that can perform high-precision reading.

  In addition, the present invention makes the distribution of heat transmitted from the light irradiator to the support member uniform, makes the heat radiation of the plurality of light emitting elements uniform, and enables high-precision reading without unevenness in illuminance. An object is to provide a reading device and an image forming apparatus.

  An image reading apparatus according to the present invention includes a light irradiator provided with a plurality of light emitting elements for irradiating a document with light and a circuit board for driving the light emitting elements, the light irradiating body provided in the main scanning direction of the document In an image reading apparatus comprising: a support member to which the support member is attached; and a traveling body to which the support member is attached and travels in the sub-scanning direction of the document, the support member has an opening in the same direction as the travel direction of the travel body. A through-hole is formed, and a heat radiation fin extending in a vertical direction from the support member is provided. The light irradiator and the support member are coupled by a plurality of coupling members, and the heat radiation fin is coupled to the coupling member. More than the number, the installation interval of the radiating fins is configured to be shorter in a portion near the coupling member than in a portion separated from the coupling member.

  With this configuration, since the through hole that opens in the same direction as the traveling direction of the traveling body is formed in the support member, air can be circulated to the support member through the through hole during traveling of the traveling body, and the support is supported from the light irradiation body. The heat transmitted to the member can be efficiently radiated with a simple configuration. For this reason, it is possible to suppress an increase in the temperature of the light emitting element while preventing an increase in manufacturing cost and weight of the image reading apparatus.

  In addition, since air can be circulated through the through-hole when the traveling body is traveling, the traveling body can be stably traveled by reducing resistance during traveling of the traveling body. As a result, it is possible to suppress a decrease in illuminance and a change in chromaticity due to heat generation of the light emitting element while performing stable running, and it is possible to improve image reading performance.

  In addition, since the heat dissipating fins extending in the vertical direction from the support member are provided, the heat transmitted from the light irradiator to the support member can be dissipated more efficiently through the heat dissipating fins when the traveling body travels, and light emission The temperature rise of the element can be further suppressed.

  In addition, the light irradiator and the support member are coupled by a plurality of coupling members, and the number of radiating fins is greater than the number of coupling members, so when the light irradiator and the support member are fastened by a fastening member such as a bolt, The light irradiator and the support member are in close contact with each other in the vicinity of the fastening member, and a minute gap is formed between the light irradiator and the support member at a position away from the fastening member.

  Therefore, the heat transmitted from the light irradiator to the support member becomes non-uniform, and the heat distribution of the support member becomes non-uniform. For this reason, the heat transferred from the light irradiator to the support member is more efficiently radiated from the radiating fins by increasing the number of radiating fins than the number of coupling members and considering the heat distribution. And the temperature rise of the light emitting element can be further suppressed.

Moreover, the installation interval of the radiation fins is configured to be shorter in a portion near the coupling member than a portion separated from the coupling member.
With this configuration, since the support member is in close contact with the light irradiation body at a position near the fastening member, heat is easily transferred from the light irradiation body to the support member, resulting in a high temperature.

  For this reason, the installation interval of the radiating fins is shorter in the portion near the coupling member than the portion separated from the coupling member, that is, by installing many, it is possible to actively dissipate heat at the highest temperature portion. The heat transmitted from the light irradiator to the support member can be radiated from the radiating fins more efficiently. For this reason, the temperature rise of a light emitting element can be suppressed further.

  According to another aspect of the present invention, there is provided a light illuminator provided with a plurality of light-emitting elements that irradiate light on a document and a circuit board that drives the light-emitting elements. In an image reading apparatus including a support member to which an irradiation body is attached and a travel body to which the support member is attached and travels in the sub-scanning direction of the document, the support member has the same direction as the travel direction of the travel body. A through-hole that opens to the support member, and a heat dissipating fin that extends in a vertical direction from the support member is provided, and the heat dissipating fin extends outward from a mounting surface that attaches the support member to the traveling body. It is composed of

  With this configuration, the heat transmitted to the heat radiating fins is radiated outward from the traveling body, so that the heat radiation area can be increased, and the heat transmitted from the light irradiator to the support member can be radiated more efficiently. be able to. For this reason, the temperature rise of a light emitting element can be suppressed further.

  According to another aspect of the present invention, there is provided a light illuminator provided with a plurality of light-emitting elements that irradiate light on a document and a circuit board that drives the light-emitting elements. In an image reading apparatus including a support member to which an irradiation body is attached and a travel body to which the support member is attached and travels in the sub-scanning direction of the document, the travel body travels in one and the other in the sub-scanning direction. Travel means that sometimes varies the traveling speed, and the support member is formed with a through hole that opens in the same direction as the traveling direction of the traveling body, the through hole being a direction in which the traveling speed of the traveling body is high It is comprised from what is a tapering shape which diameter-reduces along.

  With this configuration, since the through hole has a tapered shape along the direction in which the traveling speed is high, when the traveling body is traveling at high speed, the flow rate of the air flowing through the through hole is increased, and it is always cold. Air can be supplied to the support member. For this reason, the heat transmitted from the light irradiator to the support member can be efficiently radiated with a simple configuration, and the temperature rise of the light emitting element can be further suppressed.

  According to another aspect of the present invention, there is provided a light illuminator provided with a plurality of light-emitting elements that irradiate light on a document and a circuit board that drives the light-emitting elements. In an image reading apparatus including a support member to which an irradiation body is attached and a travel body to which the support member is attached and travels in the sub-scanning direction of the document, the travel body travels in one and the other in the sub-scanning direction. Travel means that sometimes varies the traveling speed, and the support member protrudes in a vertical direction from the bottom plate fixed to the traveling body, and opens in the same direction as the traveling direction of the traveling body. A vertical plate having a through-hole and an inclined plate extending obliquely upward from the vertical plate and having the light irradiation body attached to the upper portion thereof are integrally provided and surrounded by the bottom plate, the vertical plate, and the inclined plate The opening The taper-shaped tip of the diameter of the traveling body that opposes the traveling speed of the traveling body and the diameter of the traveling body shrinks along the direction of the traveling speed of the traveling body is opposed to the through-hole, The mounting area and the bottom plate are opposed to each other.

With this configuration, the opening surrounded by the bottom plate, the vertical plate, and the inclined position is opposed to the direction in which the traveling speed is high, so that cold air can be taken into the opening when the traveling body travels at a high speed. This air can be circulated through the through hole. For this reason, the heat transmitted from the light irradiator to the support member can be efficiently radiated with a simple configuration. For this reason, it is possible to suppress an increase in the temperature of the light emitting element while preventing an increase in manufacturing cost and weight of the image reading apparatus.
In addition, since air can be circulated through the through-hole when the traveling body is traveling, the traveling body can be stably traveled by reducing resistance during traveling of the traveling body. As a result, it is possible to suppress a decrease in illuminance and a change in chromaticity due to heat generation of the light emitting element while performing stable running, and it is possible to improve image reading performance.

Further, the image reading apparatus of the present invention is provided with a side plate that covers both ends of the bottom plate, the vertical plate, and the inclined plate in the main scanning direction, and the side plate is contracted along a direction in which the traveling speed of the traveling body is high. It is preferable that the diameter is a tapered shape.
In the image reading apparatus of the present invention, the light irradiator has an extending portion extending outward from a joint surface between the support member and the light irradiating body, and the light emitting element is disposed in the extending portion. It is preferable to be provided.
An image forming apparatus according to the present invention includes an image forming unit that forms an image on a recording medium and includes the above-described image reading apparatus.
With this configuration, it is possible to efficiently dissipate heat from the light emitting element with a simple structure, thereby suppressing an increase in the temperature of the light emitting element while preventing an increase in manufacturing cost and weight, and highly accurate reading can be performed. An image forming apparatus can be provided.

  In addition, an image forming apparatus is provided that can perform high-precision reading without unevenness in illuminance by making the distribution of heat transmitted from the light irradiator uniform to the support member, making the heat radiation of the plurality of light-emitting elements uniform. can do.

  The present invention can efficiently dissipate a light emitting element with a simple configuration, suppress an increase in manufacturing cost and weight, suppress an increase in temperature of the light emitting element, and perform highly accurate reading. An image reading apparatus and an image forming apparatus can be provided.

  In addition, the present invention makes the distribution of heat transmitted from the light irradiator to the support member uniform, makes the heat radiation of the plurality of light emitting elements uniform, and enables high-precision reading without unevenness in illuminance. A reading device and an image forming apparatus can be provided.

1 is a schematic configuration diagram of an image forming apparatus according to a first embodiment of the present invention. 1 is a side view showing the positional relationship of components of an image reading apparatus according to a first embodiment of the present invention. (A) is a schematic front view of the image reading apparatus according to the first embodiment of the present invention, and (b) is a schematic perspective view of the image reading apparatus. 1 is a perspective view of a light irradiator and a support member of an image reading apparatus according to a first embodiment of the present invention. AA arrow sectional view of FIG. Sectional drawing of the light irradiation body and support member used as a comparison with FIG. The figure which shows the back side of the supporting member of the image forming apparatus which concerns on the 2nd Embodiment of this invention. The rear view of the light irradiation body and support member of an image forming apparatus which concern on the 3rd Embodiment of this invention (A) is a rear view of the light irradiation body and support member of the image forming apparatus which concerns on the 4th Embodiment of this invention, (b) is side surface sectional drawing of a light irradiation body and a support member. Side surface sectional drawing which shows the other shape of the light irradiation body and support member of the image reader which concerns on this invention (A) is side surface sectional drawing which shows the other shape of the light irradiation body and support member of the image reader which concerns on this invention, (b) is an expanded sectional view of the through-hole part of the same figure (a). (A) is a perspective view which shows a part of heat sink of the image forming apparatus which concerns on the 5th Embodiment of this invention, (b) is a perspective view of a supporting member, (c) shows a part of light irradiation body. Perspective view The front view of the light irradiation body and support member of an image forming apparatus which concern on the 5th Embodiment of this invention The front view of the light irradiation body of the image forming apparatus which concerns on the 5th Embodiment of this invention, and the supporting member of another shape

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 6 are diagrams showing a first embodiment of an image reading apparatus and an image forming apparatus provided with the image reading apparatus according to the present invention, and show an example in which the image forming apparatus is applied to a copying machine. . The image forming apparatus is not limited to a copying machine, but can be applied to an image forming apparatus such as a facsimile machine or a multifunction machine having a copying function and a facsimile function.

  First, the configuration will be described. In FIG. 1, a copying machine 10 includes an automatic document feeder (hereinafter simply referred to as ADF) 11, a paper feeding unit 12, an image reading unit (image reading device) 13, and an image forming unit (image forming unit) 14. .

  The ADF 11 conveys the document placed on the document tray 16 onto the contact glass 15 by the separation feeding unit 17 including various rollers such as a feeding roller and a separation roller, and contacts the document after reading by the conveyance belt 18. After unloading from the glass 15, the paper is discharged onto a paper discharge tray 20 by a paper discharge means 19 comprising various paper discharge rollers.

  When reading both sides of the document, the document is returned onto the contact glass 15 by the branching mechanism provided on the paper discharge means 19 and the conveyor belt 19 to read the unread surface.

  The paper feeding unit 12 includes paper feeding cassettes 21a and 21b that store recording papers of different sizes, and paper feeding means 22 including various rollers that transport the recording papers stored in the paper feeding cassettes 21a and 21b to an image forming position. It has.

  As will be described in detail later, the image reading unit 13 drives the first carriage 35 and the second carriage 36 in the left-right direction (sub-scanning direction) in FIG. The surface is read, and the reading light is reflected by a mirror, and then taken into an image reading sensor such as a CCD by the lens unit 37.

  The image forming unit 14 includes an exposure device 23 that forms a write signal based on a read signal taken into the lens unit, a plurality of photosensitive drums 24 on which a write signal generated by the exposure device 23 is formed, A developing device 25 that is filled with toners of different colors and supplies different color toners to the respective photosensitive drums 24 to visualize the writing signals, and a visible image formed on the photosensitive drums 24 are superimposed. A transfer belt 26 for transferring the color image onto the recording paper fed from the paper supply unit 12, and a fixing for fixing the color image fixed on the recording paper to the recording paper. Device 27.

  2 and 3 are diagrams showing the configuration of the image reading unit 13. FIG. 2 is a side view showing the positional relationship between the components of the image reading unit 13.

  3A and 3B are schematic views for explaining the relationship between the drive wire 33 for driving the second carriage 36 and each pulley. FIG. 3A is a side view, and FIG. It is a figure which shows a connection state in the state seen from the top.

  2 and 3, the image reading device 13 includes a main body frame 31, a drive shaft 32, a drive wire 33, a wire drive pulley 34, a first carriage 35, a second carriage 36, a lens unit 37, a tension spring 39, and a carriage pulley 40. , Idler pulleys 41 and 42 and an image sensor 57 are provided.

  A first rail and a second rail (not shown) are provided inside the main body frame 31, and a first carriage 35 as a traveling body is slidably attached to the first rail, and the second rail is attached to the first rail. The second carriage 36 is slidably attached.

  The drive shaft 32 is connected to a motor (not shown), and wire drive pulleys 34 are attached to both ends of the drive shaft. A drive wire 33 is wound around the wire drive pulley 34, and the drive wire 33 extends in the left-right direction in FIG. 3, which is a predetermined direction.

  Two drive wires 33 are used for driving the first carriage 35 and for driving the second carriage 36. FIG. 3 shows the drive wire 33 for driving the second carriage 36.

The drive wire 33 and the idler pulleys 41 and 42 are provided one by one on the front and rear sides of the main body frame 31, but both have the same configuration and function, so the drive wire 33 and the idler pulleys 41 and 42 on one side will be described. do. That is, in the present embodiment, two wires 33 and four idler pulleys 41 and 42 are provided at the four corners of the main body frame 31.
The second carriage 36 is provided with a carriage pulley 40, and the drive wire 33 passes through the carriage pulley 40 and idler pulleys 41 and 42.

  As shown in FIGS. 4 and 5, the first carriage 35 is provided with a flat circuit board 51 having a plurality of light emitting diodes 43 as light emitting elements. The light emitting diodes 43 and the circuit board 51 are irradiated with light. The body 50 is comprised.

  A plurality of light emitting diodes 43 are provided along the main scanning direction, and the circuit board 51 controls the light emission of the light emitting diodes 43. The circuit board 51 is fixed to the support member 52 by screws 58, and the support member 52 is attached to the base portion 35a of the first carriage 35 by screws (not shown).

  The support member 52 includes a bottom plate 53 attached to the base portion 35a of the first carriage 35, a vertical plate 54 projecting vertically from the bottom plate 53, and extends obliquely upward from the vertical plate 54. The attached inclined plate 55 and the side plate 56 provided at both ends of the bottom plate 53, the vertical plate 54, and the inclined plate 55 are integrally configured.

  The support member 52 of the present embodiment is made of a metal such as sheet metal or aluminum, and the support member 52 is formed by press molding that bends one thin plate into a substantially U-shape, or die casting. . The circuit board 51 is made of glass epoxy, and the thermal conductivity of the support member 52 is higher than that of the circuit board 51.

  Further, a first mirror 44a is mounted on the lower guide plate 35b of the first carriage 35, and the light irradiated from the light emitting diode 43 to the original and reflected from the original passes through an opening 35c formed in the base part 35a. The light enters the first mirror 44a.

  The first carriage 35 is disposed between the wire drive pulley 34 and the second carriage 36, and when the first carriage 35 is pulled by the drive wire 33 and travels at a predetermined speed V, the light irradiation body 50 is brought into contact glass 15. The document placed on is sub-scanned.

  When the original is irradiated from the light emitting diode 43, the reflected light beam of the original is folded back toward the second carriage 36 by the first mirror 44 a, and this reflected light flux is mounted on the second carriage 36. After further folding back by the second mirror 44b and the third mirror 44c, the light enters the lens unit 37.

  Then, this reflected light beam is focused and imaged on an image sensor 57 such as a CCD placed on the focal plane by an imaging lens included in the lens unit 37. As a result, the image sensor 57 performs main scanning on the line on the document along the light emitting diode 43.

  In addition, the second carriage 36 cancels the overlapping of the optical path caused by the return of the light flux by the second mirror 44b and the third mirror 44c, so that the first carriage 35 has a speed that is half the speed of the first carriage 35, that is, a speed of V / 2. It travels in the same direction as the carriage 35, and the second carriage 36 travels at a travel distance (L / 2) that is half the travel distance L of the first carriage 35.

  Due to this travel speed relationship, even if the first carriage 35 and the second carriage 36 travel, the optical path length of the light flux from the document surface to the lens unit 37 does not change.

  On the other hand, the drive wire 33 includes two systems that are wound around the wire drive pulley 34 and extend in the left direction and the right direction. The portion 33a of the drive wire extending in the left direction is folded back by an idler pulley 41 whose shaft is fixed to the main body frame 31 to become a portion 33b, reaches the outer carriage pulley 40b, and is folded again here to become a portion 33c. The part is fixed to the idler pulley 41.

  Further, the portion 33d of the drive wire 33 extending in the right direction is folded back by an idler pulley 42 fixed to the main body frame 31 to become a portion 33e to reach the inner carriage pulley 40a, where it is folded back again to become a portion 33f. It is fixed to the idler pulley 42 via a tension spring 39 as a spring member.

  Further, a home position sensor (not shown) is provided on the left side in FIG. 2, and a first motor 35 travels to the left side in FIG. 2 and passes through the home position sensor to drive a drive shaft 32. When driven only by pulses, the motor is stopped.

  At this time, the wire drive pulley 34 is stopped via the drive shaft 32. This position becomes the home position position of the first carriage 35. When the reading of the document is finished, the first carriage 35 always travels to the home position position and travel is started again from this position.

  In the present embodiment, the motor, the drive shaft 32, the drive wire 33, the wire drive pulley 34, the carriage pulley 40, and the idler pulleys 41 and 42 constitute a traveling means.

  On the other hand, a plurality of through holes 59 are formed in the vertical plate 54, and the through holes 59 open in the same direction as the traveling direction of the first carriage 35. By providing the plurality of through holes 59 in this manner, the strength of the support member 52 is prevented from being lowered. Instead of the plurality of through holes 59, only one long through hole may be provided. Further, the opening 60 surrounded by the bottom plate 53, the vertical plate 54 and the inclined plate 55 faces the direction in which the traveling speed of the first carriage 35 is high.

  That is, the first carriage 35 and the second carriage 36 according to the present embodiment travel in the scanning direction on the right side in FIG. When returning to the position, the vehicle travels in the return direction on the left side in FIG.

When the vehicle travels in the return direction, it is not affected by the reading speed of the document, and therefore travels at a high speed in order to increase the productivity of the document. In the present embodiment, the opening 60 surrounded by the bottom plate 53, the vertical plate 54, and the inclined plate 55 opens in this return direction.
The opening 60 opposes the return direction in which the traveling speeds of the first carriage 35 and the second carriage 36 are high, and the diameter of the opening 60 is reduced in the return direction in which the traveling speeds of the first carriage 35 and the second carriage 36 are fast. The tapered tip is opposed to the through hole 59.
Further, the attachment region of the light irradiation body 50 on the inclined plate 55 and the bottom plate 53 are opposed to each other.
As shown in FIG. 4, the side plate 56 is provided so as to close both ends of the bottom plate 53, the vertical plate 54 and the inclined plate 55 in the main scanning direction, and the side plate 56 includes the first carriage 35 and the second carriage. 36 has a tapered shape with a reduced diameter along the return direction where the traveling speed is high.

  In the copying machine 10 having such a configuration, the first carriage 35 and the second carriage 36 are caused to travel in the main scanning direction, so that light is emitted from the light emitting diode 43 to the document surface.

  The reflected light beam of the document is folded back in the order of the first mirror 44a, the second mirror 44b, and the third mirror 44c, then enters the lens unit 37, and is placed on the focal plane by the imaging lens of the lens unit 37. The light is focused on. Thereby, the image sensor 57 scans the line on the document along the light emitting diode 43 in the main scanning direction and the sub scanning direction.

  When the reading of the document is completed, the first carriage 35 and the second carriage 36 are moved in the return direction and are moved to the home position. At the time of reading a document, the light emitting diode 43 as a heat source becomes high temperature, and the heat of the light emitting diode 43 is transmitted to the support member 52 through the circuit board 51, so that the light emitting diode 43 is dissipated by radiating the support member 52. It needs to be cooled.

  Here, as shown in FIG. 6, when the support member 52 is not formed with a through hole, the air does not pass through the support member 52 when the first carriage 35 travels in the return direction. As shown in the figure, the stagnation occurs in the opening 60, and the heat dissipation effect is reduced, resulting in resistance during travel of the first carriage 35.

  In the present embodiment, since the through hole 59 is formed in the support member 52, air can be circulated to the support member 52 through the tapered opening 60 and the through hole 59 when the first carriage 35 travels. Therefore, the heat transmitted from the light emitting diode 43 to the support member 52 can be efficiently radiated with a simple configuration, and the temperature of the light emitting diode 43 rises while preventing the manufacturing cost and weight of the copying machine 10 from increasing. Can be suppressed.

  In addition, since air can be circulated through the through hole 59 when the first carriage 35 travels, the resistance of the first carriage 35 during travel can be reduced and the first carriage 35 can be stably traveled. it can. As a result, it is possible to suppress a decrease in illuminance and a change in chromaticity of the light emitting diode 43 due to heat generation while performing stable running, and it is possible to improve image reading performance.

  Further, since the opening 60 surrounded by the bottom plate 53, the vertical plate 54, and the inclined plate 55 is opposed to the return direction in which the traveling speed of the first carriage 35 is high, the opening is opened when the first carriage 35 travels at a high speed. Cold air can be taken into the portion 60, and this air can be circulated through the through hole 59. For this reason, the heat transmitted from the light irradiation body 50 to the support member 52 can be efficiently radiated with a simple configuration.

In the present embodiment, since the material having the thermal conductivity of the support member 52 higher than that of the circuit board 51 is used, when the air is passed through the support member 52 through the through hole 59, the light irradiation body 50 A large amount of heat transmitted to the support member 52 can be efficiently radiated.
In the present embodiment, since the first mirror 44a is attached to the first carriage 35, the configuration of the copying machine 10 can be further simplified.

  FIG. 7 is a diagram showing a second embodiment of an image reading apparatus and an image forming apparatus provided with the image reading apparatus according to the present invention. The same reference numerals are given to the same components as those in the first embodiment. The description is omitted.

  In FIG. 7, heat radiating fins 61 are provided below the support member 52, and the heat radiating fins 61 extend from the support member 52 in the vertical direction. Further, the upper portion of the radiating fin 61 is located immediately below the light emitting diode 43.

  The radiating fins 61 may be provided immediately below all the light emitting diodes 43, or provided directly below the light emitting diodes 43 at a ratio of one for every two light emitting diodes 43 and one for every three light emitting diodes 43. May be.

  As described above, in the present embodiment, since the heat radiation fins 61 are provided in the vertical direction from the support member 52 positioned directly below the light emitting diode 43, the light irradiation body 50 transmits to the support member 52 when the first carriage 35 travels. The heat to be emitted can be radiated more efficiently through the radiating fins 61, and the temperature rise of the light emitting diode 43 can be further suppressed.

  FIG. 8 is a diagram showing a third embodiment of an image reading apparatus and an image forming apparatus provided with the image reading apparatus according to the present invention. The same reference numerals are given to the same components as those in the first embodiment. The description is omitted.

  In FIG. 8, the circuit board 51 and the support member 52 of the light irradiation body 50 are coupled by four bolts (coupling members) 62, and heat radiating fins 63 are provided below the support member 52.

  The radiating fins 63 extend in the vertical direction from the support member 52, and the radiating fins 63 are provided more than the number of bolts 62. Further, the installation interval of the heat dissipating fins 63 is shorter in the portion near the bolt 62 than in the portion separated from the bolt 62.

  In this way, when the circuit board 51 and the support member 52 are fastened by the bolt 62, the circuit board 51 and the support member 52 in the vicinity of the bolt 62 are brought into close contact with each other, and the circuit board 51 and the support member 52 separated from the bolt 62 are joined. A minute gap is formed on the surface. For this reason, the heat transmitted from the light irradiation body 50 to the support member 52 becomes non-uniform, and the heat distribution of the support member 52 becomes non-uniform.

  On the other hand, in the present embodiment, the number of the radiating fins 63 is larger than the number of the bolts 62, and considering the heat distribution, the installation interval of the radiating fins 63 is larger than that of the portion separated from the bolts 62. By shortening the portion in the vicinity of 62, it is possible to actively dissipate heat at the portion of the support member 52 that is at the highest temperature, and the heat transmitted from the light irradiation body 50 to the support member 52 is more from the heat radiation fins 63. Heat can be radiated more efficiently. For this reason, the temperature rise of the light emitting diode 43 can be further suppressed.

  FIG. 9 is a diagram showing a fourth embodiment of an image reading apparatus and an image forming apparatus provided with the image reading apparatus according to the present invention. The same reference numerals are given to the same components as those in the first embodiment. The description is omitted.

In FIG. 9, the support member 52 is provided with heat radiating fins 64, and the heat radiating fins 64 extend in the vertical direction from the inclined plate 55, and the leading end of the extending direction extends from the bottom plate 53 to the base of the first carriage 35. Extending outward 35a.
In addition, the installation structure of this radiation fin 64 may be either the installation structure of 2nd Embodiment or 3rd Embodiment.

  As described above, in the present embodiment, the radiation fins 64 extend from the inclined plate 55 in the vertical direction, and the radiation fins 64 extend outward from the base 35 a of the first carriage 35. By radiating the heat transmitted to the outside from the first carriage 35, the heat radiation area can be increased. For this reason, the heat transmitted from the light irradiation body 50 to the support member 52 can be radiated more efficiently, and the temperature rise of the light emitting diode 43 can be further suppressed.

  Further, the first carriage 35 travels along the first rail as described above, and the weight of the first carriage 35 is increased by the amount of the radiation fins 64, and the traveling balance is deteriorated. It is possible to end up.

  For this reason, when acceleration is applied to the first carriage 35 when the first carriage 35 is started or stopped, the first carriage 35 is tilted and an abnormal noise such as a “catching” is generated, or immediately after traveling. It may be unstable.

  In the present embodiment, since the heat radiation fins 64 are extended below the base 35a of the first carriage 35, the heat radiation fins 64 can be extended below the first rail.

  For this reason, the center of gravity can be traveled downward, the weight balance of the first carriage 35 can be improved, and the heat radiation effect can be further enhanced while stable travel without generating abnormal noise or the like can be performed. .

  In each of the above embodiments, the entire surface of the circuit board 51 is attached to the inclined plate 55 of the support member 52, but an attachment method as shown in FIG. 10 may be used. That is, as shown in FIG. 10, the circuit board 51 is extended outward from the joint surface between the inclined plate 55 of the support member 52 and the circuit board 51, and the light emitting diode 43 is provided in the extending portion 51a. Also good.

  In this case, the support member 52 is made of a resin material having a lower thermal conductivity than the circuit board 51. Here, when the glass epoxy circuit board 51 is attached to the aluminum support member 52 as in the first embodiment, the support member 52 becomes expensive when manufactured by die casting. .

  In the present embodiment, the circuit board 51 is provided with the extending portion 51a extending outward from the joint surface between the inclined plate 55 and the circuit board 51, and the light emitting diode 43 is provided on the extending portion 51a. It is unnecessary to provide the inclined plate 55 directly below the light emitting diode 43.

  For this reason, it is possible to make it difficult for heat to be accumulated in the support member 52, and to radiate heat from the light emitting diode 43 when air is circulated through the support member 52 through the through hole 59. Therefore, the support member 52 can be made of an inexpensive resin material having a lower thermal conductivity than the circuit board 51, and the manufacturing cost of the copying machine 10 can be reduced.

  Further, in each of the above embodiments, the opening area of the through hole 59 is uniform along the traveling direction of the first carriage 35. However, the present invention is not limited to this, and as shown in FIG. The taper may be tapered such that the diameter of the carriage 35 is reduced along the return direction in which the traveling speed of the carriage 35 is high.

  In this way, when the first carriage 35 is driven at a high speed in the return direction, the flow velocity of the air flowing through the through hole 65 can be increased and cold air can always be supplied to the support member 52. For this reason, the heat transmitted from the light irradiation body 50 to the support member 52 can be efficiently radiated with a simple configuration, and the temperature of the light emitting diode 43 can be further suppressed from increasing.

  12 to 14 are views showing an image reading apparatus according to the present invention and an image forming apparatus having the image reading apparatus according to a fifth embodiment. In the present embodiment, the configuration of the support member is different from that of the first embodiment, and other configurations are the same as those of the first embodiment. Therefore, the configurations similar to those of the first embodiment are used. The same numbers are assigned to and description thereof is omitted.

  12 and 13, the support member 71 includes a bottom plate 72 attached to the base portion 35 a of the first carriage 35, a vertical plate 73 protruding in the vertical direction from the bottom plate 72, and extends obliquely upward from the vertical plate 73. And an inclined plate 74 to which the circuit board 51 is attached.

  The support member 71 of the present embodiment is made of metal such as sheet metal or aluminum, and the support member 71 is formed by press molding that bends one thin plate into a substantially U shape, or die casting. . The circuit board 51 is made of glass epoxy, and the thermal conductivity of the support member 52 is higher than that of the circuit board 51.

  The inclined plate 74 of the support member 71 is provided with a plurality of pedestals 74 a on which the circuit board 51 is placed, spaced apart along the main scanning direction. The pedestals 74 a are directly below several light emitting diodes 43. positioned.

  A sheet member 75 (shown by hatching in FIG. 13) is interposed in a space defined by the circuit board 51, the pedestal 74a, and the inclined plate 74. The sheet member 75 includes a heat sink such as aluminum. Has been.

  The pedestal 74a is provided with a screw hole 76 having a screw groove formed on the inner peripheral surface thereof, and an insertion hole 51b is formed in the circuit board 51. The screw hole 76 is not shown through the insertion hole 51b. The circuit board 51 is attached to the base 74a by screwing the screws.

  As described above, in the present embodiment, the pedestal 74a is provided below the light emitting diode 43 that is a heat source, and the sheet member 75 made of a heat sink is interposed in the space defined by the circuit board 51, the pedestal 74a, and the support member 52. Therefore, the circuit board 51 can be brought into close contact with the support member 52 via the pedestal 74a and the sheet member 75.

  For this reason, even when the light emitting diode 43 is not located above the pedestal 74a, the distribution of heat transmitted from the light irradiation body 50 to the support member 52 is made uniform, and the heat radiation amount of the plurality of light emitting diodes is made uniform. be able to. Therefore, highly accurate reading without unevenness in illuminance can be performed.

  In the present embodiment, a pedestal may be provided directly below all the light emitting diodes 43. Specifically, as shown in FIG. 14, a base 74b is provided immediately below all the light emitting diodes 43, and a sheet member 77 made of a heat sink is provided between the bases 74b.

  In this way, the distribution of the heat transmitted from the light irradiation body 50 to the support member 52 can be made more uniform, and the heat radiation amount of the plurality of light emitting diodes 43 can be made more uniform.

  In each of the above embodiments, a light emitting diode is used as a light emitting element, but an EL (Electronic Luminescent) may be used.

  As described above, the image reading apparatus and the image forming apparatus according to the present invention can efficiently dissipate the light emitting element with a simple configuration, and increase in manufacturing cost and weight by suppressing the temperature rise of the light emitting element. An image reading apparatus such as a scanner apparatus provided with a light emitting element for irradiating light to read the original, and a facsimile apparatus, a copier, and a composite including the image reading apparatus. This is useful as an image forming apparatus such as a printer.

  In addition, the image reading apparatus and the image forming apparatus according to the present invention make the distribution of heat transmitted from the light irradiator to the support member uniform, uniform the heat radiation amount of the plurality of light emitting elements, and have high illuminance non-uniformity. Image reading apparatus such as a scanner apparatus provided with a light emitting element for irradiating light on a document for reading the document, and a facsimile apparatus and a copying machine provided with the image reading apparatus It is useful as an image forming apparatus such as a multifunction machine.

10 Copying machine (image forming device)
13 Image reading unit (image reading device)
14 Image forming unit (image forming means)
32 Drive shaft (traveling means)
33 Drive wire (traveling means)
34 Wire drive pulley (traveling means)
35 First carriage (running body)
40 Carriage pulley (traveling means)
41, 42 idler pulley (traveling means)
43 Light Emitting Diode (Light Emitting Element)
DESCRIPTION OF SYMBOLS 50 Light irradiation body 51 Circuit board 52,71 Support member 53,72 Bottom plate 54,73 Vertical plate 55,74 Inclined plate 59,65 Through-hole 60 Opening part 61,63,64 Radiation fin 62 Bolt (coupling member)
74a, 74b Pedestal 75, 77 Seat member

JP 2006-25303 A Japanese Utility Model Publication No. 4-135349 Japanese Patent No. 3336069

Claims (4)

A plurality of light emitters provided along the main scanning direction of the original, and a light emitter including a light emitting element for irradiating light on the original and a circuit board for driving the light emitting element; a support member to which the light emitter is attached; In the image reading apparatus provided with the traveling member attached to the support member and traveling in the sub-scanning direction of the document,
A traveling means for varying the traveling speed when the traveling body travels in one and the other in the sub-scanning direction;
The support member includes a bottom plate fixed to the traveling body, a vertical plate that protrudes from the bottom plate in a vertical direction and has a through hole that opens in the same direction as the traveling direction of the traveling body, and is inclined from the vertical plate. An inclined plate that extends upward and has the light illuminator attached to the upper part thereof,
The opening surrounded by the bottom plate, the vertical plate, and the inclined plate is a tapered tip that faces the direction in which the traveling speed of the traveling body is high and reduces the diameter along the direction in which the traveling speed of the traveling body is high. Facing the through hole,
An image reading apparatus, wherein an attachment region of the light irradiator on the inclined plate and the bottom plate are opposed to each other.   A side plate that closes both ends of the bottom plate, the vertical plate, and the inclined plate in the main scanning direction is provided, and the side plate has a tapered shape that decreases in diameter along a direction in which the traveling speed of the traveling body is high. The image reading apparatus according to claim 1.   The light irradiator has an extending portion extending outward from a joint surface between the support member and the light irradiating body, and the light emitting element is provided in the extending portion. The image reading apparatus according to claim 1 or 2.   An image forming apparatus comprising: an image forming unit that forms an image on a recording medium; and the image reading apparatus according to claim 1.

Images