JP4398579B2 - Photoelectric conversion unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a photoelectric conversion unit used as an exposure system for an electrophotographic printer.
[0002]
[Prior art]
Conventionally, an LED print head, which is a photoelectric conversion unit, is used as an exposure system for an electrophotographic printer. The structure of the conventional LED print head will be described below. FIG. 9 is a sectional view showing a conventional LED print head.
[0003]
In FIG. 9, the LED print head 1 is configured by mounting a plurality of LED arrays 2 provided with a plurality of light emitting units (not shown) inside and a plurality of driver ICs 3 for controlling the LED arrays 2 on a substrate 4. The LED array unit 5, the base 6 on which the LED array unit 5 is mounted, the SLA 7 that connects the image of the light emitting unit on a photosensitive drum (not shown), and the LED array unit 5 in a state where the SLA 7 is held. And a holder 8 having both ends fixed to the base 6.
[0004]
Next, the operation at the time of printing of the LED print head 1 in the above configuration will be described.
[0005]
The LED print head 1 receives print data from the main body of the electrophotographic printer and turns on the LED array 2. The image of the light emitting point of the lit LED array 2 is connected to the photosensitive drum via the SLA 7, thereby forming an electrostatic latent image on the photosensitive drum.
[0006]
Next, a method for manufacturing the conventional LED print head 1 will be described.
[0007]
The LED array unit 5 is manufactured by mounting the LED array 2 and the driver IC 3 on the substrate 4 and fixing the LED array 2 and the driver IC 3 to the substrate 4 by wire bonding. The LED print head 1 is made by assembling the LED array unit 5, the SLA 7, the holder 8, and the base 6. These operations are performed in an environment such as a clean room with little dust and dirt.
[0008]
[Problems to be solved by the invention]
Conventional LED print heads are manufactured in a clean room or other environment where there is little dust or dirt. However, since holders and bases are manufactured in a normal factory, avoid the attachment of foreign objects at the beginning of manufacturing. I can't. Therefore, these members are cleaned before assembly or foreign substances are removed by air shower, but even if these removal operations are performed, it is difficult to completely remove foreign substances from the members. there were.
[0009]
The LED array unit is also manufactured in a clean room, but it has been difficult to completely remove foreign matters such as dust attached to the substrate from the LED print head. Therefore, if foreign matter adheres to the member, the foreign matter remains inside the LED print head after it is assembled.
[0010]
If the foreign matter adheres to anything other than the photoelectric conversion part (LED array), there is no particular problem. However, if foreign matter adheres to the LED array, the foreign matter becomes a shadow and the light in this part is blocked, allowing printing. There was a problem that printing abnormalities such as white lines and black lines would occur.
[0011]
Therefore, it is necessary to remove the foreign matter. However, when the foreign matter is found in the inspection after assembling the LED print head, there is a problem that the removal of the foreign matter increases the man-hours. In addition, there is a case where a foreign object that has not been placed on the LED array immediately after assembly moves in the process of use after product shipment and is placed on the LED array. In this case, there is a problem from the user that not only the man-hours for removing the foreign matter are generated, but also the user is inconvenienced and the product image is deteriorated.
[0012]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a photoelectric conversion device having a housing that is attached to a cover that is rotatably provided in the apparatus main body and includes a photoelectric conversion unit and a substrate on which the photoelectric conversion unit is provided. In the unit, the unit includes a holding unit that holds foreign matter that has entered the housing, and the holding unit includes a first surface that extends from the housing toward the substrate, and the first surface. And a second surface extending to face the inner surface of the housing .
[0013]
According to the said structure, the foreign material inside a housing | casing is fixed to the holding part holding a foreign material . Therefore, it is possible to prevent foreign matters from being placed on the photoelectric changing unit.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element common to each drawing.
[0015]
First Embodiment FIG. 1 is a cross-sectional view showing an LED print head according to the first embodiment, and FIG. 2 is an explanatory diagram showing a configuration of a print process unit section according to the first embodiment. .
[0016]
First, the configuration of the printing process unit will be described.
[0017]
In FIG. 2, the printing process unit 9 is provided with a photosensitive drum 10 that carries a toner image. An LED print which is a photoelectric conversion unit that forms an electrostatic latent image on the photosensitive drum 10 by exposing the photosensitive drum 10 to the surface of the photosensitive drum 10 and a charging roller 11 for electrostaticizing the photosensitive drum 10. A head 12, a developing roller 17 that is transported from the toner cartridge 13 through a toner container 14 by a stirring bar and a sponge roller 15 (not shown), and attaches the toner 16 charged to (−) to the electrostatic latent image; A transfer roller 20 that is pressed against the photoconductive drum 10 with a constant force and transfers a toner image formed on the surface of the photoconductive drum 10 to a sheet 19 that is a printing medium conveyed by a feed roller 18; A bias voltage opposite to the charging polarity is applied to remove the residual toner remaining on the surface of the photosensitive drum 10 after transfer, and the photosensitive drum Cleaning roller 21 is any provided to perform neutralization of 0 surface. Further, a fixing device (not shown) for fixing the transferred toner 16 onto the paper 19 is provided on the downstream side in the transport direction of the paper 19 with respect to the printing process unit unit 9, and this fixing device has a built-in heat roller. ing.
[0018]
Further, the amount of contact (push-in amount) between the transfer roller 20 and the photosensitive drum 10 due to securing of escape when the paper 19 passes between the photosensitive drum 10 and variations in the outer diameter of the transfer roller 20 and the photosensitive drum 10. ), The transfer roller 20 is pressed toward the photosensitive drum 10 by the spring 22.
[0019]
Next, the configuration of the LED print head 12 will be described.
[0020]
In FIG. 1, the LED print head 12 includes a plurality of LED arrays 23, which are photoelectric conversion units each including a plurality of light emitting units, and a plurality of driver ICs 24 that control the LED array 23 arranged on a substrate 25. An LED array unit 26 configured, a base 27 on which the LED array unit 26 is mounted, an SLA 28 for connecting an image of the LED array 23 on the photosensitive drum 10, and the LED array in a state where the SLA 28 is held. It comprises a unit 26 and a holder 29 whose both ends are fixed to a base 27. The SLA 28 functions as a window. The holder 29 and the base 27 constitute a housing that covers the inside of the LED print head 12, whereby the LED array 23, driver IC 24, substrate 25, LED array unit 26, and SLA 28 are provided inside the housing. It is done.
[0021]
The LED print head 12 is provided with an adhesive 30 that is a foreign matter fixing portion on the substrate 25 in the vicinity of the LED array 23 and extending along the LED array 23. Examples of the adhesive 30 include double-sided tape, adhesive silicone resin, and grease. Silicone resin and grease are selected so that they have high viscosity and do not flow out even at high temperatures and do not flow out. For example, in the case of grease, an adhesive layer can be easily formed by forming a thin layer in a brush or sponge.
[0022]
By providing such an adhesive 30, the foreign matter adheres to the adhesive 30, and the foreign matter does not move any further and is not placed on the photoelectric conversion unit (LED array 23). Further, immediately after the assembly, the foreign material which is not in the adhesive 30 and moved in the other part moves in the LED print head 12 and is placed on the adhesive 30, and the foreign material does not move any more. It wo n’t be on top. Therefore, it is possible to prevent the LED array 23 from being affected.
[0023]
Next, the operation at the time of printing of the LED print head 12 in the above configuration will be described.
[0024]
The LED print head 12 receives print data from a printer apparatus main body (not shown) and turns on the LED array 23. An image of the light emitting point of the lit LED array 23 is connected to the photosensitive drum 10 via the SLA 28, whereby an electrostatic latent image is formed on the photosensitive drum 10.
[0025]
As described above, in the first embodiment, by providing the adhesive 30 in the vicinity of the LED array 23, the foreign matter is attached and fixed to the adhesive 30, and the foreign matter is placed on the photoelectric conversion unit (LED array 23). Can be prevented.
[0026]
Second embodiment Next, a second embodiment will be described. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. FIG. 3 is an explanatory view showing a mounting state of the LED print head of the second embodiment in an electrophotographic printer, and FIG. 4 is a cross-sectional view showing the LED print head of the second embodiment.
[0027]
As shown in FIG. 3, when the LED print head 31 is mounted on an electrophotographic printer, the LED print head 31 is disposed on the upper side of the photosensitive drum 10, and the LED array 23 is disposed on the upper side and the SLA 28 is disposed on the lower side. Is done.
[0028]
Since the LED print head 31 is mounted in this way, foreign matter is likely to fall to the SLA 28 and the holder 29 side. Therefore, in the second embodiment, as shown in FIG. 4, the same adhesive 32 as in the first embodiment is placed on the holder 29 in the vicinity of the SAL 28 and extends along the SAL 28. Provided.
[0029]
By arranging the adhesive 32 in the holder 29 in the vicinity of the SAL 28 in this way, when the LED print head 31 is mounted on the electrophotographic printer, the foreign matter falls to the SLA 28 and the holder 29 side and adheres to the adhesive 32. The foreign matter does not move any further and does not rest on the LED array 23. Immediately after the assembly, the foreign matter that is not in the adhesive 32 moves in the LED print head 31 and is placed on the adhesive 32, and the foreign matter does not move any more. It wo n’t be on top. Therefore, it is possible to prevent the LED array 23 from being affected.
[0030]
Further, in the first embodiment, the adhesive 30 is provided in the vicinity of the LED array 23. However, when the adhesive 30 is provided on the substrate 25, the LED array 23 is scratched or the wires near the LED array 23 are provided. There is a risk of touching and breaking. In the second embodiment, since the adhesive 32 is provided in the holder 29, the adhesive 30 can be provided in the holder 29 in advance before the LED array unit 26 is mounted, and thus there is a risk of breaking the LED array unit 26. There is no.
[0031]
As described above, in the second embodiment, the foreign matter adheres to the adhesive 32 and is fixed, so that the foreign matter can be prevented from being placed on the LED array 23, and there is no risk of breaking the LED array unit 26. Thus, foreign matter can be prevented from being placed on the LED array 23.
[0032]
Third embodiment Next, a third embodiment will be described. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. FIG. 5 is a cross-sectional view showing an LED print head according to a third embodiment.
[0033]
In the first embodiment and the second embodiment, the adhesive 30 and 32 are provided on the LED array unit 26 or the holder 29. In the LED print head 36 of the third embodiment, the holder 34 is provided with a rib 35 that forms an uneven shape. And the adhesive 33 is provided along this uneven | corrugated shape. Thereby, since the area of the adhesive 33 increases, the fixing effect of a foreign material can be raised further.
[0034]
That is, a large number of ribs 35 or grooves having a width of about 1 mm and a depth of about 2 mm are formed in the holder 34, and the adhesive 33 is provided along the uneven shape of the ribs 35, so that foreign matter adheres to the adhesive material 33. Probability increases. Further, by using a gel-like material such as silicone resin or grease as the adhesive 33, it is possible to easily apply the rib 35 into the recess.
[0035]
As described above, in the third embodiment, the foreign matter adheres to the adhesive 33 and is fixed, so that the foreign matter can be prevented from being placed on the LED array 23 and the ribs 35 formed on the holder 34 can be prevented. By providing the pressure-sensitive adhesive 33 along the concavo-convex shape, the area where the pressure-sensitive adhesive material is provided (applied) increases, so the effect of fixing foreign matter can be further increased. As a result, there is less possibility of foreign matter adhering to the LED array 23 than in the first and second embodiments, and print quality is not impaired.
[0036]
Fourth embodiment Next, a fourth embodiment will be described. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. FIG. 6 is an explanatory view showing a mounting state of the LED print head of the fourth embodiment on an electrophotographic printer, and FIG. 7 is a cross-sectional view showing the LED print head of the fourth embodiment.
[0037]
In the first embodiment, the second embodiment, and the third embodiment, foreign matter is fixed with an adhesive. Providing the LED print head 37 with a double-sided tape, a silicone resin, or the like, which is an adhesive, takes time and costs for the adhesive. Further, as shown in the first embodiment, when the adhesive 30 is provided on the substrate 25, there is a risk of scratching the LED array 23 or touching and breaking the wires near the LED array 23. Therefore, in the LED print head 37 according to the fourth embodiment, the movement of the foreign matter is prevented without providing the adhesive, and the foreign matter is prevented from being placed on the LED array 23.
[0038]
In FIG. 6, the electrophotographic printer 41 is provided with an upper cover 42 that is rotatable in the direction of arrows AB. The LED print head 37 is usually mounted on the upper cover 42 shown in FIG. 6 on the upper side of the photosensitive drum 10 shown in FIG. 3 in the direction shown in FIG. Although the photosensitive drum 10 is in the printing process unit unit 9 shown in FIG. 2, the printing process unit unit 9 is a consumable part and needs to be replaced. Therefore, as shown in FIG. 6, the upper cover 42 is rotated in the direction of arrow A when the printing process unit 9 is replaced. Note that the upper cover 42 may be rotated in the direction of the arrow A in some cases when the paper 19 shown in FIG. When the upper cover 42 is rotated in the arrow A direction, the LED print head 37 is also moved in the arrow A direction.
[0039]
Then, as shown in FIG. 7, when the LED print head 37 is attached to the upper cover of an electrophotographic printer (not shown), a trap 39, which is a holding portion for holding foreign matter, is located at the lowest position of the holder 38. It is formed in a state extending along the SLA 28. The trap 39 is formed by the holder 38 extending from the lower end portion 38a so as to form a substantially quadrangular shape excluding the entrance portion where foreign matter enters.
[0040]
The foreign matter travels down the slope of the holder 38 and falls to the lower end 38 a of the holder 38. When the upper cover 42 is rotated in the direction of arrow A, the foreign matter moves in the direction of arrow E from the lower end 38 a of the holder 38 and enters the trap 39. In this case, when the upper cover 42 is rotated in the direction of the arrow B, the foreign matter may continue to be held in the trap 39 or may fall from the trap 39 to the lower end portion 38 a of the holder 38. Accordingly, the foreign matter is held in the trap 39 or is positioned at the lower end 38 a of the holder 38. Therefore, it is possible to prevent foreign matter from moving onto the LED array 23 without providing an adhesive.
[0041]
As described above, in the fourth embodiment, it is possible to prevent the foreign matter from being placed on the LED array 23 by holding the foreign matter in the trap 39. That is, even if there is no adhesive, if the trap structure is provided in the holder 38, the foreign matter can be prevented from freely moving inside.
[0042]
In order to increase the degree of cleaning of foreign matter inside the LED print head 37, in addition to such a trap 39, as shown in the first embodiment, the second embodiment, and the third embodiment. It is preferable to provide an adhesive layer and remove with the trap 39 together with the adhesive. Further, for example, by providing an adhesive layer such as grease in the trap 39, the foreign matter can be further retained in the trap 39, and the foreign matter once retained in the trap 39 is prevented from being released. can do.
[0043]
Fifth embodiment Next, a fifth embodiment will be described. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. FIG. 8 is an explanatory diagram showing a state where the LED print head according to the fifth embodiment is mounted on an electrophotographic printer.
[0044]
In the first embodiment, the second embodiment, the third embodiment, and the fourth embodiment, the object is to fix the foreign matter with an adhesive or a trap. In order to fix the foreign matter with an adhesive or a trap, the foreign matter must be moved there. Therefore, the LED print head 40 according to the fifth embodiment includes an adhesive or a trap and a mechanism that facilitates moving foreign matter to the adhesive or trap.
[0045]
In the fifth embodiment, a plurality of holding members 43 shown in FIG. 8 are provided on the upper cover 42 shown in FIG. 6, and the end portions of the holding members 43 are provided on the base 27 of the LED print head 40. The same number of engaging members 44 as 44a are rotatably held in the direction of arrow CD. Thereby, the LED print head 40 is attached to the upper cover 42 which is a part of the electrophotographic printer 41 so as to be rotatable in the direction of the arrow CD.
[0046]
Thus, when the upper cover 42 is rotated in the direction of arrow A shown in FIG. 6 or when it is rotated in the direction of arrow B to close it, the LED print head 40 is moved to the direction indicated by arrow C- in FIG. By rotating in the D direction and vibrating, the foreign matter inside the LED print head 40 becomes easier to move than when the LED print head is in a fixed state.
[0047]
As described above, in the fifth embodiment, even if a foreign object adheres to the LED array 23, the LED print head 40 vibrates when the operation of rotating the upper cover 42 in the arrow AB direction is performed. The foreign matter moves from the LED array 23 and easily moves to an adhesive (not shown) or a trap. As a result, foreign matters are easily fixed to an adhesive or trap (not shown). In addition, even if the foreign material fixed by the adhesive or the trap vibrates, it does not move further.
[0048]
In addition, in the said 1st Embodiment to 5th Embodiment, although demonstrated as an LED array, even if it is an image sensor array, there can exist the same effect.
[0049]
【The invention's effect】
As described above in detail, according to the present invention, the foreign matter fixing portion for fixing the foreign matter is provided inside the housing, whereby the foreign matter inside the housing is fixed to the foreign matter fixing portion. Therefore, it is possible to prevent foreign matters from being placed on the photoelectric conversion unit. As a result, even if foreign matter is in the photoelectric conversion unit after the photoelectric conversion unit is assembled, there are no man-hours for removing the foreign matter, and there is no occurrence of printing abnormalities such as white stripes or black stripes due to foreign matters. An excellent photoelectric conversion unit can be provided. Furthermore, there will be no complaints from users.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an LED print head according to a first embodiment.
FIG. 2 is an explanatory diagram illustrating a configuration of a printing process unit unit according to the first embodiment.
FIG. 3 is an explanatory diagram illustrating a mounting state of an LED print head according to a second embodiment on an electrophotographic printer.
FIG. 4 is a cross-sectional view showing an LED print head according to a second embodiment.
FIG. 5 is a cross-sectional view showing an LED print head according to a third embodiment.
FIG. 6 is an explanatory diagram illustrating a mounting state of an LED print head according to a fourth embodiment on an electrophotographic printer.
FIG. 7 is a cross-sectional view illustrating an LED print head according to a fourth embodiment.
FIG. 8 is an explanatory diagram illustrating a mounting state of an LED print head according to a fifth embodiment on an electrophotographic printer.
FIG. 9 is a cross-sectional view showing a conventional LED print head.
[Explanation of symbols]
12 LED print head 23 LED array 25 Substrate 29 Holder 30 Adhesive 31 LED print head 32 Adhesive 33 Adhesive 34 Holder 35 Rib 36 LED print head 37 LED print head 38 Holder 39 Trap 40 LED print head 41 Electrophotographic printer 42 Upper Cover 43 Holding member 44 Engaging member

Claims (9)

It is attached to a cover that is pivotally provided on the device body,
In the photoelectric conversion unit having a housing provided with a photoelectric conversion unit and a substrate on which the photoelectric conversion unit is disposed,
A holding portion for holding foreign matter that has entered the housing;
The holding portion has a first surface extending from the housing toward the substrate;
A photoelectric conversion unit comprising: a second surface extending from the first surface and extending so as to face the inner surface of the housing.   The photoelectric conversion unit according to claim 1, wherein a foreign matter fixing portion for fixing foreign matter is provided inside the housing.   The photoelectric conversion unit according to claim 2, wherein the foreign matter fixing portion is provided on the substrate side inside the housing.   The photoelectric conversion unit according to claim 2, wherein the foreign matter fixing portion is provided on the housing side inside the housing.   The photoelectric conversion unit according to any one of claims 2 to 4, wherein the foreign matter fixing part is an adhesive substance to which foreign matter adheres. The holding portion includes a photoelectric conversion unit according to claim 1, any one of claim 5, characterized in that the adhesive material of foreign matter adheres is provided.   The photoelectric conversion unit according to claim 1, wherein the photoelectric conversion unit is an LED array.   The photoelectric conversion unit according to claim 1, wherein the photoelectric conversion unit is an image sensor array.   The photoelectric conversion unit according to claim 1, wherein the housing is rotatably attached to the cover.

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