JP5471463B2 - Method for manufacturing printed wiring board device and method for manufacturing print head - Google Patents

Description

  The present invention relates to a collective printed wiring board in which a plurality of printed wiring boards (bare boards) are connected.

  When a printed wiring board device is manufactured by fixing (mounting) electronic components on a relatively small printed wiring board, it takes time to position and transport the printed wiring board, resulting in a reduction in manufacturing efficiency. For this reason, the collective printed wiring board which connected the printed wiring board mutually using the connection piece etc. is used conventionally (for example, refer patent documents 1-8).

  This collective printed wiring board is generally handled as a single board in the manufacturing stage, and electronic components are generally fixed to pads or the like formed on the front surface and / or back surface thereof. That is, the assembled printed circuit board is directly subjected to a heating and cooling process such as SMD (Surface Mount Device) reflow, COB (Chip On Board) cure, etc., when fixing electronic components.

  Then, divide the printed wiring board from the aggregate printed wiring board and inspect each printed wiring board device, or inspect each printed wiring board device as it is, and divide the printed wiring board from the aggregate printed wiring board. By doing so, a printed wiring board device as a finished product is completed.

Japanese Patent Laid-Open No. 04-320597 JP-A-11-176974 JP-A-11-163482 Japanese Patent Laid-Open No. 02-031490 Japanese Patent Laid-Open No. 03-250800 Japanese Patent Laid-Open No. 06-112600 Japanese Patent Laid-Open No. 06-169137 JP 2009-283959 A

  As shown in FIG. 13, a conventional collective printed circuit board 90 in which a plurality of long printed circuit boards 92 and discard boards 95 are connected by connecting pieces 94 is a short circuit direction (X direction) of the printed circuit board 92. Connection pieces 94 formed on both end faces (one end face 96 and the other end face 97) face each other.

  For this reason, when a thermosetting adhesive or cream solder is applied to the collective printed wiring board 90 and an electronic component is placed on the thermosetting adhesive or cream solder and heated and cooled, Expansion and contraction in the short direction (X direction) of the printed wiring board 92 hardly occurs, and the expansion and contraction in the short direction of the printed wiring board 92 increases as the distance from the connecting piece 94 increases. Then, the amount of expansion and contraction in the short direction is maximized at the intermediate point 91 between the adjacent connecting pieces 94.

  That is, in the longitudinal direction (Y direction) of the printed wiring board, portions with a small amount of expansion and contraction in the short direction appear alternately. The printed wiring board 92 having such a portion with a large difference in expansion and contraction has a problem that warping and distortion are large when the connecting piece 94 is cut and divided (separated).

  Further, even if electronic components are placed with high precision on the front and / or back surfaces of the individual printed wiring boards 92 constituting the collective printed wiring board 90, a reflow oven, oven, and the like are used to fix the electronic components to the printed wiring boards 92. When heated by, for example, the amount of expansion and contraction in the short direction differs depending on the printed wiring board 92 portion, there is a problem that positional displacement of electronic components occurs.

  The present invention has been made to solve such a problem, and it is an object of the present invention to reduce warpage and distortion of individual printed wiring boards constituting the aggregate printed wiring board.

(First aspect )
The first aspect includes a plurality of long printed wiring boards arranged in order in the short direction and connected to each other by connecting pieces, and a discarded board connected by connecting pieces on the outside of the plurality of printed wiring boards. The present invention relates to an aggregate printed wiring board. And the printed wiring board has the connecting pieces on both end faces in the short direction not facing each other, and all the printed wiring boards on the odd number have the same position in the longitudinal direction of the connecting pieces on both end faces in the short direction. In addition, all the printed wiring boards of the even number are characterized in that the positions in the longitudinal direction of the connecting pieces on both end faces in the short side direction are the same.

(Second embodiment )
The second aspect is the first aspect , in which the printed wiring board is formed by alternately connecting one end surface connecting piece in the short direction and the other connecting end piece in the short direction from one end to the other end in the longitudinal direction. It is characterized by that.

  With such a configuration, even when the assembly printed wiring board on which electronic components are placed is heated and cooled, it is possible to reduce warpage and distortion of individual printed wiring board devices obtained by cutting the connecting pieces.

(Third aspect )
A 3rd aspect is related with the printed wiring board apparatus obtained by fixing a some electronic component to the assembly printed wiring board of a 1st aspect, or a 2nd aspect , and cut | disconnecting with a connection piece.
With such a configuration, it is possible to provide a printed wiring board device in which electronic components are mounted on the printed wiring board with high accuracy with less warping and distortion.

(4th aspect )
The fourth aspect includes the printed wiring board device according to the third aspect , in which the electronic component is a light emitting element, and a lens array in which a plurality of rod lenses are arranged and arranged, and one lens surface of the lens array faces the light emitting element. As described above, the present invention relates to a print head in which a lens array and a printed wiring board device are fixed to a housing.
With such a configuration, the printed wiring board device is less warped and distorted, and the light emitted from the light emitting element is less bent. Therefore, it is possible to provide a print head with high linearity of the imaging line formed by the imaging point.

(5th aspect )
A fifth aspect relates to an image forming apparatus including a photoconductor that forms an electrostatic latent image on a surface and a printhead according to a fourth mode facing the photoconductor.
With this configuration, an image forming apparatus that can form a highly accurate image can be provided.
(First invention)
In the first invention, a plurality of long printed wiring boards arranged in order in the lateral direction and connected to each other by a plurality of connecting pieces, and connected by the plurality of connecting pieces outside the plurality of printed wiring boards. In the collective printed wiring board composed of a discarded board, the printed wiring board is configured such that the plurality of connecting pieces on both end faces in the short direction are not opposed to each other, and all the printed wiring boards in the odd number are in the short direction. The longitudinal positions of the plurality of connecting pieces on the both end faces of the printed circuit board are the same, and the printed wiring boards of all even-numbered sheets have the same longitudinal position on the both end faces in the short side direction. Preparing an aggregate printed wiring board, wherein a thermosetting adhesive is applied to the aggregate printed wiring board, and a plurality of the thermosetting adhesive applied to the aggregate printed wiring board The optical element is positioned, and heating the thermosetting adhesive, a plurality of light emitting elements is fixed to the set printed wiring board, cutting the plurality of connecting pieces, a method of manufacturing a printed wiring board device.
(Second invention)
According to a second aspect of the present invention, in the method for manufacturing a printed wiring board device according to the first aspect, in the printed wiring board, the connecting piece on one end face in the short side direction and the connecting piece on the other end face in the short side direction are in the longitudinal direction. The collective printed wiring board formed alternately from one end to the other is prepared.
(Third invention)
According to a third aspect of the present invention, there is provided the printed wiring board device according to claim 1 or 2, wherein a lens array is fixed to the housing, and the one lens surface of the lens array is opposed to the light emitting element. The present invention relates to a method for manufacturing a print head for fixing a printed wiring board device manufactured by the method.

  According to the present invention, even when the collective printed wiring board on which electronic components are placed is heated and cooled, it is possible to reduce the warpage and distortion of individual printed wiring board devices obtained by being separated by the connecting pieces.

(Example 1) which is a top view of an assembly printed wiring board (Example 1) which is a top view of the assembly printed wiring board which fixed the electronic component. (Example 1) which is a perspective view of the edge part of the assembly printed wiring board which fixed the electronic component. (Example 1) which is a top view of a printed wiring board apparatus. (Example 1) which is a perspective view of the edge part (W part of FIG. 4) of a printed wiring board apparatus. (Example 1) which is a side view of a printed wiring board apparatus. FIG. 3 is a plan view of the print head (Example 1). 1 is a perspective view of an end portion of a print head (Example 1). FIG. 1 is a cross-sectional view of a print head (Example 1). (Example 2) which is a top view of an assembly printed wiring board FIG. 10 is a diagram for explaining a configuration of an image forming apparatus (third embodiment). (Example 3) which is a figure which shows the positional relationship of a print head and a photoreceptor. It is a top view of the conventional collective printed wiring board.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

An embodiment of the present invention will be described with reference to FIGS.
1 is a plan view of the collective printed wiring board 1, FIG. 2 is a plan view of the collective printed wiring board in which electronic components 10 are fixed to the collective printed wiring board 1 shown in FIG. 1, and FIG. 3 is a collective print shown in FIG. 4 is a perspective view of an end portion of the wiring board 1, FIG. 4 is a plan view of a printed wiring board device 11 obtained by dividing the collective printed wiring board shown in FIGS. 2 and 3, and FIG. 5 is a printed wiring shown in FIG. FIG. 6 is a side view of the printed wiring board device shown in FIG. 5 (arrow A), FIG. 7 is a plan view of the print head 20 using the printed wiring board device 11, and FIG. 8 is a perspective view of an end portion of the print head 20 shown in FIG. 7, and FIG. 9 is a cross-sectional view of the print head 20 shown in FIGS.

(Aggregate printed wiring board)
As shown in FIG. 1, the collective printed wiring board 1 according to the present invention is arranged in a line in the short direction (X direction) of the printed wiring board 2 and is connected to each other by connecting pieces 4 (five pieces). A long printed wiring board 2 and a discarded board 5 that surrounds the outside of the five printed wiring boards 2 are connected by a connecting piece 4.

  Each printed wiring board 2 includes both end faces in the short side direction (X direction) (one odd-numbered printed wiring board has one end face 27 and the other end face 28, and even-numbered printed wiring boards have one end face 29 and the other. The connecting piece 4 on the end face 30) is non-opposing (not in an opposing relationship). In other words, if attention is paid to the printed wiring board 6, the connecting piece 4 formed on one end portion (right side of the paper surface) of the printed wiring board 6 is connected to one end portion (paper surface) of the other end surface 28 of the printed wiring board 6. This relationship is established for all the connecting pieces 4 formed on the one end surface 27 and the other end surface 28 of the printed wiring board 6. The relationship of the connecting pieces 4 exemplarily showing the printed wiring board 6 is established for all the printed wiring boards 2 constituting the collective printed wiring board 1.

  Further, all the odd-numbered printed wiring boards 6, 61 and 62 are positioned in the longitudinal direction (Y direction) of the connecting piece 4 on both end faces (one end face 27 and the other end face 28) in the short side direction (X direction). Are the same. That is, all the connection pieces 4 formed (remaining) on the one end face 27 when the substantially central portions of the connection pieces 4 formed on the odd-numbered printed wiring boards 6, 61 and 62 are cut and overlapped. And all the connecting pieces 4 formed (remaining) on the other end surface 28 overlap.

  Further, all of the even printed wiring boards 7 and 71 have the same position in the longitudinal direction (Y direction) of the connecting piece 4 on both end faces (one end face 29 and the other end face 30) in the short side direction (X direction). It is. That is, when the substantially central portions of the connecting pieces 4 formed on the even-numbered printed wiring boards 7 and 71 are cut and overlapped, all the connecting pieces 4 formed (remaining) on the one end face 29 overlap. And all the connection pieces 4 formed (remaining) on the other end face 30 overlap.

  As shown in FIG. 1, the printed wiring board 2 includes a connecting piece 4 on one end face in the short direction (X direction) and a connecting piece 4 on the other end face in the short side direction in the longitudinal direction (Y direction). It is desirable that they are formed alternately from one end to the other end.

  Further, on the surface of the printed wiring board 2, a solid pattern 3 made of a copper foil for fixing a light emitting element as an electronic component to be described later in a straight line shape (straight line shape or staggered shape) in the longitudinal direction is formed. . Note that the light emitting element refers to a semiconductor element in which a plurality of (for example, 256) light emitting points are formed in a straight line.

  As shown in FIG. 1, the connection pieces 4 that connect the printed wiring boards 2 and the printed wiring board 2 and the discarded board 5 are formed by providing a plurality of elongated holes 9 that penetrate in the plate thickness direction (Z direction). Has been. Note that the five long printed wiring boards 2 have the same electrical functions such as the routing of the wiring patterns and the positions of the pads.

(Printed wiring board device)
Next, a printed wiring board device obtained by fixing light emitting elements to individual printed wiring boards 2 constituting the aggregate printed wiring board 1 will be described.
First, a thermosetting adhesive is applied to the solid pattern 3 of all the printed wiring boards 2 (printed wiring boards 6, 7, 61, 62 and 71) of the collective printed wiring board 1. Then, 20 light emitting elements 10 are positioned with high accuracy on the thermosetting adhesive applied to the solid pattern 3 of each printed wiring board 2 using the technique described in Japanese Patent No. 4289656. Then put.

  After a total of 100 light emitting elements 10 are placed on the thermosetting adhesive applied to the collective printed wiring board 1, the collective printed wiring board 1 is placed in a heating furnace (oven) and heated to, for example, 110 ° C. Then, the thermosetting adhesive is cured. Then, all the light emitting elements 10 are fixed to the collective printed wiring board 1.

  Then, as shown in FIG. 5, the wire 14 is used to electrically connect the pad 14 on the surface of the light emitting element 10 and the pad 15 connected to the wiring pattern 16 on the surface of the printed wiring board 2 by the gold wire 13. Connect to. Although a plurality of sets of pads 14, gold wires 13 and pads 15 are actually formed, only one set is shown in FIG. 5 for ease of explanation. After the wire bonding for all the light emitting elements 10 is finished, the printed piece board device 11 can be obtained by dividing (cutting) the connecting pieces 4.

  Since the collective printed wiring board 1 according to the present invention employs the above-described configuration, even if the collective printed wiring board 1 on which the light emitting element 10 is placed is heated and cooled, the difference in the amount of expansion and contraction in the short direction is large. There is no part. For this reason, even if all the light emitting elements 10 are fixed to the collective printed wiring board 1 by heating and then the connecting pieces 4 are cut, the individual printed wiring board devices 11 obtained are less warped and distorted. Moreover, since the printed wiring board device 11 is less warped and distorted, the bending of the optical axis of the light emitted from each light emitting point of the light emitting element 10 is small.

  As shown in FIG. 1, when the connecting pieces 4 are alternately formed in the longitudinal direction of the printed wiring board 2, the difference in expansion and contraction generated in the printed wiring board 2 due to heating and cooling of the collective printed wiring board 1 is smaller. As a result, the above-described effect increases. Furthermore, if the connecting pieces 4 are alternately formed in the longitudinal direction of the printed wiring board 2 and the intervals between the connecting pieces in the longitudinal direction are made substantially equal, the effect is further increased.

  Strictly speaking, the position of the connecting piece 4 of the printed wiring board 2 is different between the odd numbered sheets (6, 61 and 62) and the even numbered sheets (7 and 71). The odd number and the even number are different. Therefore, when it is necessary to fix the light emitting element 10 to the printed wiring board 2 with higher accuracy, two types of operation programs for the apparatus for positioning the light emitting element 10 on the printed wiring board 2 may be prepared. In other words, it is only necessary to prepare two types of correction values for electronic components that take into account differences in warpage and distortion between odd-numbered and even-numbered printed wiring boards. For this reason, the collective printed wiring board 1 according to the present invention also has an effect of reducing the number of production preparation steps.

(Print head)
Next, the case where the above-described printed wiring board device 11 is used for the print head 20 shown in FIGS. 7 to 9 will be described.
The print head 20 has a housing 23 in which a lens array 22 in which a plurality of rod lenses 21 are arranged and fixed is fixed with an adhesive or the like, and one lens surface of the lens array 22 and the light emitting element 10 are opposed to the housing 23. And a printed wiring board device 11 fixed with an adhesive or the like.

  As shown in FIG. 9, when the print head 20 emits a light emitting point (LED) of the light emitting element 10 fixed to the surface of the printed wiring board device 11, the emitted light is emitted from the light emitting point to the lens array 22. Thus, the distance to the image forming point (focal position) that converges (condenses) is set to the conjugate length TC. The conjugate length TC is a distance L from the light emitting point to the lower surface (one lens surface) of the lens array 22, a distance L from the upper surface (the other lens surface) of the lens array 22 to the imaging point, and the lens array 22. And a relationship of TC = T + 2L is established.

  As described above, the print head 20 according to the present invention is less warped or distorted by the printed wiring board device 11, and the bending of the optical axis of the light emitted from each light emitting point of the light emitting element 10 is small. High linearity.

Another embodiment of the present invention will be described with reference to FIG.
FIG. 10 is a plan view of the collective printed wiring board 42 according to the present invention. For easy understanding, the same portions as those in the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted.

  The main difference between the second embodiment and the first embodiment is that a pad (not shown) is formed on the surface of the printed wiring board 41 instead of the pattern 3. That is, the pad is formed at a position where the electronic component 10 is fixed. Even with this configuration, the same effects as those of the first embodiment can be obtained.

  A third embodiment according to the present invention will be described with reference to FIGS. FIG. 12 is a partially enlarged view of a part of FIG. 11 for easy understanding of the positional relationship between the print head 20 and the photosensitive drum 25.

(Image forming device)
As shown in FIG. 11, the image forming apparatus according to the present invention is a so-called tandem digital color printer 131, and an image forming process unit 110 that forms an image corresponding to image data of each color, and an image forming process unit 110. And an image processing unit 140 that performs predetermined image processing on the image data received from the personal computer 102 or the image reading apparatus 103.

  The image forming process unit 110 includes four image forming units 111Y, 111M, 111C, and 111K that are arranged in parallel at a predetermined interval. Each of these image forming units 111Y, 111M, 111C, and 111K forms a latent image on the photosensitive drum 25 as an image carrier that carries a toner image, and the surface of the photosensitive drum 25. A charging device 113 that is uniformly charged at a predetermined potential, a print head 20 as an exposure device that exposes the photosensitive drum 25 whose surface is charged by the charging device 113, and an electrostatic latent image obtained by the print head 20 A developing device 115 for developing and a cleaner (blade) 116 for cleaning the surface of the photosensitive drum 25 after transfer are provided.

  Further, a density detection circuit 117 that detects the toner image density of a test patch (density sample) formed on the photosensitive drum 25 is provided in the vicinity of the downstream side of the developing device 115 so as to face the photosensitive drum 25. It has been. The density detection circuit 117 is connected to the control unit 130 and outputs a toner image density detection value. Here, the image forming units 111Y, 111M, 111C, and 111K are configured in substantially the same manner except for the toner stored in the developing device 115. The image forming units 111Y, 111M, 111C, and 111K form yellow (Y), magenta (M), cyan (C), and black (K) toner images, respectively.

  In addition, the image forming process unit 110 includes an intermediate transfer belt 121 onto which the toner images of the respective colors formed on the photosensitive drums 25 of the image forming units 111Y, 111M, 111C, and 111K are transferred, and the image forming units 111Y. , 111M, 111C, and 111K toner images are sequentially transferred (primary transfer) to the intermediate transfer belt 121, and a primary transfer roll 122 as a primary transfer charging device and a superimposed toner image transferred onto the intermediate transfer belt 121 are recorded. A secondary transfer roll 123 as a secondary transfer charging device that performs batch transfer (secondary transfer) onto a paper P that is a material (recording paper), and a fixing device 125 that fixes the secondary transferred image onto the paper P. I have.

  The image forming process unit 110 performs an image forming operation based on a control signal such as a synchronization signal supplied from the control unit 130. At that time, image data input from the personal computer 102 or the image reading device 103 is subjected to image processing by the image processing unit 140 and supplied to each of the image forming units 111Y, 111M, 111C, and 111K via the interface. .

  For example, in the yellow image forming unit 111Y, the surface of the photosensitive drum 25 uniformly charged at a predetermined potential by the charging device 113 emits light based on the image data obtained from the image processing unit 140. The electrostatic latent image is formed on the photosensitive drum 25 by being exposed by the print head 20.

  This electrostatic latent image is developed by the developing device 115, and a yellow toner image is formed on the photosensitive drum 25. Similarly, magenta, cyan, and black toner images are formed on the respective photosensitive drums 25 of the image forming units 111M, 111C, and 111K.

  The color toner images formed on the respective photosensitive drums 25 of the image forming units 111Y, 111M, 111C, and 111K are sequentially transferred by the primary transfer roll 122 onto the intermediate transfer belt 121 that rotates in the direction of arrow A in FIG. A toner image superimposed on the intermediate transfer belt 121 is formed by electrostatic attraction.

  The superimposed toner image is conveyed to an area (secondary transfer portion) where the secondary transfer roll 123 is disposed as the intermediate transfer belt 121 rotates. When the superimposed toner image is conveyed to the secondary transfer unit, the paper P is supplied to the secondary transfer unit in accordance with the timing at which the toner image is conveyed to the secondary transfer unit.

  Then, the superimposed toner images are collectively electrostatically transferred onto the conveyed paper P by the transfer electric field formed by the secondary transfer roll 123 in the secondary transfer portion. Thereafter, the sheet P on which the superimposed toner image is electrostatically transferred is peeled off from the intermediate transfer belt 121 and conveyed to the fixing device 125 by the conveying belt 124.

  The unfixed toner image on the paper P conveyed to the fixing device 125 is fixed on the paper P by being subjected to fixing processing by heat and pressure by the fixing device 125. Then, the paper P on which the fixed image is formed is conveyed to a paper discharge placement unit (not shown) provided in the discharge unit of the digital color printer 131. That is, since the image forming apparatus according to the third embodiment includes the print head 1 according to the present invention, a high-quality image can be formed.

  The above-described embodiments have been illustrated for the purpose of explanation, and the present invention is not limited thereto. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions can be made without departing from the technical idea of the present invention.

  For example, in the above-described embodiment, the electronic component 10 is fixed to the printed wiring board 2 in a staggered manner, but may be fixed on a straight line. In the above-described embodiments, the printed wiring board is a collective printed wiring board having five sheets, but a plurality of printed wiring boards (two or more) may be used.

  In the embodiment described above, the electronic component (light emitting element) 10 is fixed to the printed wiring board 2 with a thermosetting adhesive. However, the present invention is not limited to this, and cream solder (solder paste) is used. It may be used and fixed by heating in a reflow furnace.

In addition, this invention can also be grasped | ascertained as follows.
A plurality of long printed wiring boards arranged in order in the short direction and connected to each other by connecting pieces,
In a collective printed wiring board composed of a discarded board connected by the connecting piece on the outside of the plurality of printed wiring boards,
In the printed wiring board, the connecting pieces on both end faces in the short direction are non-opposing
When all the printed wiring boards of an odd number are stacked, the connecting pieces overlap,
The collective printed wiring board, wherein the connecting pieces overlap when all the printed wiring boards of even number are stacked.

  The present invention is applied to an aggregate printed wiring board in which a plurality of printed wiring boards to which electronic components are fixed are connected.

DESCRIPTION OF SYMBOLS 1 Collective printed wiring board 2 Printed wiring board 3 Solid pattern 4 Connecting piece 5 Discarded board 6 Odd-numbered printed wiring board 7 Even-numbered printed wiring board 8 Display (short direction)
DESCRIPTION OF SYMBOLS 10 Light emitting element 11 Printed wiring board apparatus 20 Print head 21 Rod lens 22 Lens array 23 Housing 25 Photosensitive drum

Claims (3)

In the lateral direction are arranged in the order consists of a plurality of elongated printed circuit board which are connected to each other by a plurality of connecting pieces, the discarded substrate coupled with the plurality of connecting pieces on the outside of the printed wiring board of the plurality of In the collective printed wiring board, the printed wiring board is configured such that the plurality of connecting pieces on both end faces in the short-side direction are not facing each other, and all the printed wiring boards on the odd numbered sheets are on the both end faces in the short-side direction. characterized in that it is the same longitudinal position of the plurality of connecting pieces, all of the printed wiring board of the even-numbered, the longitudinal position of said plurality of connecting pieces at both ends of the lateral direction are the same Prepare an assembly printed wiring board
Applying a thermosetting adhesive to the assembly printed wiring board,
Positioning a plurality of light emitting elements on the thermosetting adhesive applied to the aggregate printed wiring board,
Heating the thermosetting adhesive to fix the plurality of light emitting elements to the aggregate printed wiring board;
Cutting the plurality of connecting pieces;
Manufacturing method of printed wiring board device. In the printed circuit board, and the connecting piece of one end surface in the short direction, and the connecting piece of the other end face of the short direction, the set print formed alternately toward the other end from one end in the longitudinal direction of Prepare the wiring board ,
Method of manufacturing a print circuit board according to claim 1. Fix the lens array to the housing,
The printed wiring board device manufactured by the method for manufacturing a printed wiring board device according to claim 1 or 2 is fixed to the housing so that one lens surface of the lens array and the light emitting element face each other.
A method for manufacturing a printhead.

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