JP5178574B2 - Substrate unit and scanner - Google Patents

Description

  The present invention relates to a board unit including a board on which electronic components are mounted and a fixing base on which the board is fixed, and a scanner including the board unit.

  Patent Document 1 describes an electrical device that includes a radiator and a metal substrate that is mounted with a heat-generating component and is fixed to the radiator at four tightening locations with screws. In this electric device, the heat generating component is mounted outside the range surrounded by a virtual straight line connecting the tightening points with screws.

JP 2007-243110 A (FIG. 1 etc.)

  When a component that dislikes a change in position, such as an image sensor, is mounted together with a heat generating component on the substrate, the position change of the image sensor is effectively prevented even if the heat generating component is arranged as described above. The imaging result may not be accurate.

  The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a technique capable of effectively preventing a change in position of a component such as an image sensor.

In order to solve the above-mentioned problem, the substrate unit according to claim 1 is a fixing unit that fixes the substrate on the fixing table at a plurality of first and second fixing points on the substrate, a fixing table, and the substrate. and member, a part dislike position change, in the first region of the polygonal shape whose vertices are the first fixing portion, a first component mounted on the substrate, a heating element, said first And a second part arranged at a position other than the first region in a polygonal second region having the first fixed portion as a vertex with the first fixed portion included therein.

  According to a second aspect of the present invention, in the board unit of the first aspect, the first component may be an optical sensor.

  According to a third aspect of the present invention, in the board unit according to the first aspect, the first component may be an image sensor.

  In order to solve the above problem, a scanner according to a fourth aspect includes the substrate unit according to the third aspect and an optical member that guides the light reflected from the document to the image sensor.

  According to the present invention, since the first component is disposed at a position that is not easily affected by the warp of the substrate due to heat generated from the second component, it is possible to suppress fluctuations in the position of the first component.

1 is a perspective view showing an external appearance of a multifunction machine 1 according to an embodiment of the present invention. FIG. 3 is a perspective view illustrating a part of a scanner 104 of the multifunction machine 1. FIG. 3 is an exploded perspective view of the configuration shown in FIG. 2. FIG. 4 is a cross-sectional view taken along the line A-A ′ of the substrate unit 1 included in the scanner 104. Plan view of substrate unit 1 The top view of the board | substrate unit 10 which concerns on 2nd Embodiment. The top view of the board | substrate unit 11 which concerns on 3rd Embodiment. The top view of the board | substrate unit 12 which concerns on 4th Embodiment. The top view of the board | substrate unit 111 which concerns on a comparison form. The top view of the board | substrate unit 112 which concerns on another comparative form. Furthermore, the top view of the board | substrate unit 113 which concerns on another comparative form.

[1] First Embodiment An embodiment of the present invention will be described below with reference to the drawings.

(Multifunction machine 1)
FIG. 1 is a perspective view showing an appearance of a multifunction machine 100 as an example of an apparatus incorporating a board unit. In the following description, “up” and “down” mean an upward direction and a downward direction, respectively, in the normal installation posture of the multifunction machine.

  As shown in FIG. 1, the multifunction peripheral 100 includes a main body 101 and a document conveying device 102. The document feeder 102 is disposed on the main body 101.

  The main body 101 includes a scanner 104, a printing unit 105, a paper cassette 106, and a platen glass 107. The platen glass 107 is disposed on the upper surface of the main body 101 at a position facing the document conveying device 102, the scanner 104 is provided on the upper side of the main body 101, that is, directly below the platen glass 107, and the printing unit 105 is provided on the scanner 4. The sheet cassette 106 is provided at the bottom and further on the bottom of the main body 101.

  The scanner 104 includes an imaging device 4 and a lens 1041 shown in FIG. 2 described later, a light source and a mirror (not shown), and the like. The image sensor 4 and the lens 1041 will be described later with reference to FIG. Light from a light source (not shown) is guided to the platen glass 107 by a mirror, and light reflected by the document on the platen glass is guided to the image sensor 4 by the mirror and the lens 1041. The image sensor 4 converts light into an analog electrical signal. Thereafter, an analog signal is converted into a digital signal by an analog front end circuit (not shown). This digital signal is used for printing or transmission as image data through an image processing circuit (not shown). The scanner 104 can read an image from both a document placed on the platen glass 107 and a document conveyed by the document conveying device 102 and passing on the platen glass 107.

  The printing unit 105 prints image data on a sheet. Specifically, an image forming apparatus using an electrophotographic method or an inkjet method is used.

  The paper cassette 106 stores paper supplied to the printing unit 105.

  The document conveying device 102 includes a plurality of rollers and a driving device that rotates these rollers, and conveys the document so as to pass over the platen glass 107 by the rotating rollers.

(Scanner 104)
FIG. 2 is a perspective view of a part of the scanner 104, and FIG. 3 is an exploded view of a part of the scanner 104.

  As shown in FIGS. 2 and 3, the scanner 104 includes a substrate unit 1, a lens 1041, a bottom plate 1042, and the like.

  As shown in FIGS. 2 and 3, the substrate unit 1 includes a substrate 2, a substrate fixing sheet metal 3, and screws 5. Mounting holes 20 and 30 are provided in the substrate 2 and the substrate fixing sheet metal 3, respectively. The attachment holes 20 and 30 correspond to fixed locations. The screw 5 is an example of a fixing member, and fixes the substrate 2 to the substrate fixing sheet metal 3 by passing through the attachment holes 20 and 30. The substrate fixing sheet metal 3 is fixed to the bottom plate 1042 by screws 32.

  The substrate 2 is an example of a fixed base, and the image sensor 4 is mounted. A more detailed structure of the substrate 2 will be described later with reference to FIG.

  The substrate fixing sheet metal 3 includes a horizontal portion that is parallel to the bottom plate 1042 and fixed so as to face the bottom plate 1042, and a vertical portion that is perpendicular to the horizontal portion. A through hole 31 is provided in the vertical portion.

  As shown in FIGS. 2 and 3, the lens 1041 is fixed to the lens mounting plate 1043, and the lens mounting plate 1043 is fixed to the bottom plate 1042 by screws 1044. The lens mounting plate 1043 has a horizontal portion that is parallel to the bottom plate 1042 and fixed so as to face the bottom plate 1042, and a vertical portion that is perpendicular to the horizontal portion. A through hole 1043a is provided in the vertical portion.

  As described above, the reflected light from the document is guided to the lens 1041 by the mirror. The light that has passed through the lens 1041 passes through the through hole 1043 a of the lens mounting plate 1043 and the through hole 31 of the substrate fixing sheet metal 3 in order and enters the image sensor 4.

(Board unit 1)
Details of the configuration of the substrate unit 1 will be described with reference to FIGS. FIG. 4 is a cross-sectional view taken along the line AA ′ of the substrate unit 1, and FIG. 5 is a plan view of the substrate unit 1.

  As shown in FIG. 4, in the substrate unit 1, the imaging device 4 is mounted on one surface of the substrate 2, and the substrate 2 is directed so that the surface on which the imaging device 4 is mounted faces the substrate fixing sheet metal 3. Fixed. On the other surface, a heat generating component 6 which is an example of a heat generating element is mounted.

  As the image sensor 4, a conventionally known image sensor such as a CCD or a CMOS can be used.

  The heat generating component 6 is not limited to a specific electronic component, and may be any device that generates heat. Among the heat generating components 6, it is preferable that the arrangement position of the drive circuit for the image sensor 4 is set to have a short distance from the image sensor 4.

  As shown in FIG. 5, the substrate 2 is rectangular, and the screws 5, that is, the mounting holes 20 and 30 are provided at two locations on a straight line parallel to the longitudinal direction of the substrate 2. The image pickup device 4 is provided between the two screws 5, that is, on the line segment L 1 connecting the two screws 5.

  The heat generating component 6 is provided at a position off the line segment L1. More specifically, it is as follows.

  Assuming two straight lines L2 that pass through the two screws 5 and are perpendicular to the line segment L1, the substrate 2 is divided into regions A1, A2, and A3 by the two straight lines L2. Regions A1 and A2 include edges in the longitudinal direction of the substrate 2, and region A3 is disposed between regions A1 and A2. The image sensor 4 is disposed in the area A3. The heat generating component 6 is disposed in the region A1 or A2, or both.

  Since the image sensor 4 is arranged at a position on the line segment connecting the screws 5 where position fluctuation hardly occurs, accurate image data can be obtained. Further, since the heat generating component 6 is disposed at a position deviated from the line segment, even if the substrate 2 is warped due to the heat generated from the heat generating component 6, fluctuations in the position of the imaging element 4 are suppressed.

  Furthermore, since the heat generating component 6 is arranged in the region A1 or A2, the screw 5 is arranged between the image pickup device 4 and the heat generating component 6, so that fluctuations in the position of the image pickup device 4 are further suppressed. Is done. “Between the image pickup element 4 and the heat generating component 6” means that the image pickup element 4, the screw 5 and the heat generating component 6 are arranged in a straight line, and these members (4 to 6) are in a straight line. Includes the case where the screw 5 and the heat generating component 6 are arranged in this order in the order from the image pickup device 4 even if they are separated. That is, the image sensor 4 is disposed between the screws 5, and the heat generating component 6 is disposed on the edge side of the substrate 2 with respect to the screws 5.

  It should be noted that any component that does not generate heat or a component that generates a small amount of heat so as not to warp the substrate 2 can be arranged not only in the regions A1 and A2, but also in the region A3 and further on the line segment L1. .

[2] Second Embodiment FIG. 6 shows a plan view of a substrate unit 10 according to a second embodiment of the present invention. The board unit 10 is provided in the scanner 104 of the multi-function device 100 similarly to the board unit 1 of the first embodiment, and has the same configuration as the board unit 1 except for the arrangement of the image sensor, screws, and heat generating components. Therefore, members having the same functions as those already described with reference to FIGS. 1 to 5 may be denoted by the same reference numerals and description thereof may be omitted.

  As shown in FIG. 6, the board unit 10 includes four screws 50. As the screw 50, the same member as the screw 5 can be used. A line segment L1 connecting the screws 50 forms a rectangle having a side parallel to the rectangular side of the edge of the substrate 2 with the screw 50 as a vertex. The heat generating component 6 is arranged in the area A4 outside the rectangle, and the image sensor 4 is arranged in the area A5 inside the rectangle. That is, the image sensor 4 is disposed at a position surrounded by the screws 5, and the heat generating component 6 is disposed on the edge side of the substrate 2 with respect to the screws 5.

  Even with such an arrangement, as in the first embodiment, fluctuations in the position of the image sensor 4 when the substrate 2 is warped by heat generated from the heat generating component 6 are suppressed.

[3] Third and Fourth Embodiments FIGS. 7 and 8 are plan views of substrate units 11 and 12 according to third and fourth embodiments of the present invention, respectively. The board units 11 and 12 are provided in the scanner 104 of the multi-function device 100 similarly to the board unit 1 of the first embodiment, and have the same configuration as the board unit 1 except for the arrangement of the image sensor, screws, and heat generating components. . Therefore, members having the same functions as those already described with reference to FIGS. 1 to 5 may be denoted by the same reference numerals and description thereof may be omitted.

  As shown in the plan view of FIG. 7, the board unit 11 is further provided with another screw 51 arranged on the same straight line as the screw 5 so as to sandwich the two screws 5 therebetween. The configuration is the same as that of the substrate unit 1. As described with reference to FIG. 5, the image sensor 4 is disposed between the inner screws 5. And the heat-emitting component 6 should just be arrange | positioned in the position which remove | deviates from the line segment L1, especially the area | region A1 or A2, and it is accept | permitted to arrange | position between the inner side screw 5 and the outer side screw 51.

  As described above, when the image sensor 4 is arranged on a plurality of line segments connecting the screws, the heat generating component 6 is positioned away from the line segment whose end point is the screw closest to the image sensor 4. In particular, when the substrate 2 is divided by a straight line that passes through a screw that defines the end point and is perpendicular to the line segment, the line segment is disposed at a position outside the region including the line segment. It is preferable.

  As shown in FIG. 8, the substrate unit 12 is arranged such that a line segment L3 connecting each screw 52 forms a rectangle outside the rectangle where the screw 50 is a vertex (position close to the edge of the substrate 2). The configuration is the same as that of the substrate unit 11 of FIG. As described with reference to FIG. 6, the image sensor 4 is arranged in an inner rectangle (a rectangle formed by the line segment L <b> 1). And the heat-emitting component 6 should just be arrange | positioned outside the inner rectangle (in area A4), and is allowed to be arranged in the outer rectangle (in the rectangle formed by the line segment L3). .

  Thus, when the image sensor 4 is arranged in a plurality of polygons surrounded by line segments connecting screws, the heat generating component 6 is the image sensor of the polygon including the entire image sensor 4. A screw closer to 4 is provided at a position deviated from the polygon at the apex.

  Even with the arrangement as described above, the positional fluctuation of the image sensor 4 can be effectively suppressed.

[4] Other Embodiments (4-1) The image sensor 4 is only an example of a first component. The first part is a part that dislikes change in position, and examples thereof include sensors and laser light sources in an electrophotographic image forming apparatus. Examples of sensors include a temperature sensor and the like. Examples include elements and other optical sensors.

  (4-2) As a “polygon” having a screw as a vertex, a rectangle is cited in the above-described embodiment, but the polygon may be a shape having three or more vertices. Various shapes such as hexagons are included.

  (4-3) In the above embodiment, the image sensor 4 and the heat generating component 6 are provided on different surfaces of the substrate 2, but the image sensor 4 and the heat generating component 6 are provided on the same surface. Also good.

  (4-4) In any of the embodiments, the position variation of the image sensor 4 is effectively suppressed when the distance between the image sensor 4 and the nearest screw is smaller.

  (4-5) One screw (5 etc.) is provided for each fixing point, but the fixing member can fix the substrate to the fixing base at a plurality of fixing points per one fixing member. It may be.

  (4-6) The board unit of the present invention is applicable to various apparatuses other than the scanner.

  (4-7) Techniques obtained by appropriately combining the above-described embodiments are also included in the embodiments of the present invention.

[5] Comparative Mode (5-1) First Comparative Mode FIG. 9 is a plan view of the substrate unit 111 according to the comparative mode. As shown in FIG. 9, the board unit 111 has the same configuration as the board unit 1 of the first embodiment except that the heat generating component 6 and the imaging element 4 are also arranged between the screws 5. According to this arrangement, when the heat generating component 6 generates heat, the substrate 2 is warped in the region A3 between the screws 5 in the substrate 2. As a result, the position of the image sensor 4 arranged in the region A3 varies.

(5-2) Second Comparative Mode FIG. 10 is a plan view of a substrate unit 112 according to another comparative mode. As shown in FIG. 10, the board unit 112 has the same configuration as the board unit 10 of the second embodiment, except that the heat generating component 6 as well as the imaging element 4 are arranged in a rectangle with the screw 50 as a vertex. . According to this arrangement, the position of the image sensor 4 is likely to be affected by the warp of the substrate 2 due to heat from the heat-generating component 6, as in the substrate unit 111 of the first comparative embodiment.

(5-3) Third Comparative Example FIG. 11 shows a plan view of a substrate unit 113 according to another comparative example. As shown in FIG. 11, the board unit 113 has the same configuration as the base board unit 1 of the first embodiment, except that the arrangement positions of the heat generating component 6 and the image sensor 4 are switched. That is, the image sensor 4 is disposed at a position that is out of the space between the screws 5. Thus, when the image sensor 4 is arranged at the free end of the substrate 2, the position of the image sensor 4 is likely to fluctuate due to vibration or the like.

DESCRIPTION OF SYMBOLS 1 Board | substrate unit 2 Board | substrate 3 Board | substrate fixed sheet metal 4 Imaging element (1st component)
5 Screw (fixing member)
6 Heat-generating parts (second parts)
20, 30 Mounting hole (fixed part)
100 MFP 104 Scanner

Claims (4)

A substrate,
A fixed base;
A fixing member for fixing the substrate on the fixing base at a plurality of first and second fixing points on the substrate;
A component that dislikes a change in position, and a first component that is mounted on the substrate in a polygonal first region having the first fixed portion as a vertex;
A heating element, wherein the first region is included therein and is disposed at a position other than the first region in a polygonal second region having the second fixed portion as a vertex ;
A substrate unit comprising: The board unit according to claim 1, wherein the first component is an optical sensor. The board unit according to claim 1, wherein the first component is an image sensor. A substrate unit according to claim 3,
An optical member that guides the light reflected from the document to the image sensor.

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