JP2000321517A - Optical scanner and image forming device mounted with same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dustproof glass from falling and breaking in the maintenance by simple constitution. SOLUTION: A dustproof glass engagement guide 16 with which the dustproof glass 15 is engaged detachably is provided at the opening edge part of the opening 14 of glass 13 on the upper side in the figure 1 and when the dustproof glass 15 is engaged with the dustproof glass engagement guide part 16 and moved to a predetermined position, the dustproof glass 15 closes the opening 14 completely. Then the dustproof glass 15 is prevented from falling even when the cover 13 is detached without detaching the dustproof glass 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device provided with a cover for preventing dust from entering into an optical housing in which an optical scanning system for scanning a laser beam is housed, and a dustproof glass, and an optical scanning device therefor. The present invention relates to an image forming apparatus equipped with.

[0002]

2. Description of the Related Art An image forming apparatus such as an electrophotographic digital copying machine or a laser printer is provided with an optical scanning device (writing unit) for scanning a laser beam. The optical scanning device is usually arranged near the image forming unit in many cases. Such an optical scanning device is provided with a dust-proof glass in an optical path in order to prevent dust from entering an optical housing in which an optical scanning system for scanning a laser beam is housed.

In an electrophotographic image forming apparatus equipped with such an optical scanning device, toner is indispensable for visualizing a latent image formed on a photosensitive member. In recent years, the toner has been miniaturized to improve image quality. On the other hand, an airflow is generated in the apparatus main body of the image forming apparatus to cool each unit that generates heat. For this reason, the minute toner floats in the apparatus main body due to the influence of the air current or the like, though the amount is small.

[0004] If such toner floating in the apparatus main body adheres to the dust-proof glass of the optical scanning device, the image quality deteriorates. For example, the toner adheres to the dust-proof glass using a dedicated fan and a duct. To prevent
A cleaning member for cleaning the dust-proof glass is provided so as to clean the dust-proof glass (for example, JP-A-9-80343 and JP-A-9-80343).
No. 80875).

[0005]

However, if a fan or a duct is provided to prevent the toner from adhering to the dust-proof glass, or if a cleaning member for cleaning the dust-proof glass is provided, the optical scanning is increased accordingly. In some cases, the configuration of the apparatus becomes complicated, resulting in an increase in cost.

Therefore, it is conceivable to adopt a configuration in which the dust-proof glass is held between the cover and the optical housing so that the dust-proof glass can be easily removed and the dust-proof glass can be easily cleaned. However, in this case, when replacing each part of the other optical scanning system such as the polygon scanner in the optical housing, or when removing the cover carelessly when cleaning those parts, There is a possibility that the dust-proof glass may be dropped and damaged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and can be manufactured at a relatively low cost by using a simple structure. It is an object of the present invention to provide an optical scanning device which does not damage system components and an image forming apparatus equipped with the same.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a cover for preventing dust from entering an optical housing containing an optical scanning system for scanning a laser beam, and a cover for the cover. An optical scanning device comprising: a dustproof glass provided to close an opening for emitting the formed laser light to prevent dust from entering the optical housing from the opening and to form an optical path; A dustproof glass engaging guide for detachably engaging the dustproof glass was provided at the opening edge of the cover, and the dustproof glass was engaged with the dustproof glass engaging guide and inserted to a predetermined position. Sometimes, the dust-proof glass blocks all the openings.

Accordingly, the dust-proof glass is attached to the cover so as to cover all of the openings from which the laser light is emitted by the dust-proof glass engagement guide provided on the cover, so that the dust-proof glass is removed during maintenance or the like. Even if the cover is removed without doing so, it is possible to prevent the dust-proof glass from being dropped and damaged.

[0010] The dustproof glass engagement guide may be formed integrally with the cover. Then, as compared with the case where the dust-proof glass engagement guide portion and the cover are formed separately, the number of parts can be reduced, so that it can be manufactured at a lower cost and the number of assembling steps can be reduced. it can.

Further, in the optical scanning device, an urging elastic portion for urging the dust-proof glass inserted to a predetermined position to a flat portion near the opening of the cover so as to close the opening is formed with the cover. It is good to form integrally. Then, the dustproof glass inserted to the predetermined position is brought into close contact with the cover so as to cover all the openings of the cover by the biasing elastic portion formed integrally with the cover.

Further, in any one of the above optical scanning devices, an eave portion is provided at a position proximate to the opening of the cover along a side edge of the opening in a detachable direction of the dustproof glass with a predetermined amount of projection. Preferably, the dustproof glass engaging guide is formed on the eaves. Then, since the eaves protrude by a predetermined amount at a position close to the opening of the cover, the toner falling from above the optical scanning device without adding other components can be used by the eaves. As a result, the toner can be prevented from adhering to the dust-proof glass.

In the optical scanning device having the eaves protruding therefrom, a dustproof glass engaging guide for detachably engaging the dustproof glass with the other side edge of the cover opening opposite to the one side edge is also provided. It is preferable to form it near the opening. Then, the dustproof glass is held by the dustproof glass engagement guide formed near the opening on the other side edge, so that the dustproof glass can be more reliably held.

Further, when any one of the above optical scanning devices is mounted on the apparatus main body to constitute an image forming apparatus, the operation side for attaching and detaching the dustproof glass to and from the dustproof glass engaging guide portion of the cover is attached to the apparatus main body. It should be on the front side. Then, when cleaning the dust-proof glass, the worker does not have to go around or behind the machine to detach and operate the dust-proof glass or move the image forming apparatus to a position where it is easy to clean. .

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of an optical scanning device according to an embodiment of the present invention, in which an optical scanning system in an optical housing is not shown, and FIG. 2 is an image forming apparatus equipped with the optical scanning device. FIG. 1 is a schematic diagram showing a laser printer as an apparatus. The laser printer shown in FIG. 2 is an image forming apparatus using an electrophotographic method, and has an optical scanning device (writing unit) 3 disposed close to the image forming unit 2 in the upper part of the apparatus main body 1.

The image forming unit 2 of the laser printer includes
A photosensitive drum 8 rotatable in the direction indicated by the arrow is provided, and the uniformly charged surface of the photosensitive drum 8 is scanned with laser light emitted from the optical scanning device 3 in accordance with an image signal. A latent image is formed there. The latent image is developed by applying toner in the developing unit 9 to become a visible image (toner image), and the visible image is provided in a sheet feeding unit 4, 5 provided below the apparatus main body 1 in four stages. , 6 and 7 are transferred to the paper fed from the paper feed stage selected. Then, the sheet is conveyed to the fixing unit 11 and is discharged after the toner image is fixed.

The optical scanning device 3 is configured to store dust in an optical housing 12 in which an optical scanning system (not shown in FIG. 1 and described later in FIG. 4) for scanning the laser beam L shown in FIG. Cover 13 for preventing intrusion and cover 1
A dustproof glass 15 provided to close the opening 14 for emitting the laser light formed in the optical housing 12 to prevent dust from entering the optical housing 12 through the opening 14 and to form an optical path. I have.

The optical scanning device 3 includes a cover 13
At the upper edge of the opening 14 in FIG.
When the dust-proof glass 15 is engaged with the dust-proof glass engaging guide 16 and the dust-proof glass 15 is engaged with the dust-proof glass engaging guide 16 and the dust-proof glass 15 is inserted into a predetermined position as shown in FIG. The dustproof glass 15 covers the entire opening 14.

The optical housing 12 of the optical scanning device 3 is formed by molding, for example, with resin. A laser diode (LD), a collimating lens, an aperture, an LD, and the like, as shown in the perspective view of the optical scanning device 3 with the cover 13 removed in FIG.
A laser diode unit 17 composed of a control board is mounted. In the optical housing 12,
A sound insulation glass 19, a polygon mirror 20, an fθ mirror 21, a return mirror 22, a BTL 23, a reflection mirror 24, a photo sensor 25, and the like are provided.

The laser light emitted from the laser diode unit 17 passes through a cylindrical lens (not shown) and a sound insulating glass 19 in this order, and is further reflected and scanned by a polygon mirror 20. Further, the laser light is f
An image is formed on the photosensitive drum 8 described with reference to FIG. 2 through the image forming elements of the θ mirror 21, the reflection mirror 22, and the BTL 23.

The laser light that has passed near the scanning start side end of the folding mirror 22 is reflected by the reflection mirror 24 and forms an image on the photosensor 25. The signal detected thereby is used as a synchronization detection signal for determining the image start position of each scanning line. The cover 13 that covers the upper part of the optical housing 12 has a shape as shown in FIG.
A trumpet-shaped receiving portion 26 into which the dustproof glass 15 is inserted is formed in a portion on the near side of the opening 14.

Then, the dustproof glass 15 inserted to a predetermined position (the position shown in FIG. 5) is inserted into the flat portion 27 on the near side near the opening of the cover 13 so that the entire opening 14 is closed. A biasing elastic portion 28 for biasing the cover 13 is formed integrally with the cover 13. An urging elastic part 29 for urging the dustproof glass 15 inserted to the above-mentioned predetermined position toward the flat part 31 is also integrally formed on the flat part 31 on the back side near the opening of the cover 13. Has formed.

Thus, as shown in FIG. 3, when the dust-proof glass 15 is inserted from the receiving portion 26 to a predetermined position shown in the drawing, the dust-proof glass 15 is located on the near side of the dust-proof glass 15 as shown in FIG. The biasing elastic portion 28 whose left side is bent is placed on the flat portion 27 by the biasing elastic portion 28, and the biasing elastic portion 2 is located on the far side (right side in the figure).
9 presses against the plane portions 31 respectively. Therefore, since there is no gap between the cover 13 and the dust-proof glass 15, dust can be prevented from entering the cover 13 from between the cover 13 and the dust-proof glass 15.

The cover 13 has one side edge 14a (FIG. 1) of the opening 14 at a position close to the upper side of the opening 14 (see FIG. 8 because it cannot be seen in FIG. 3). An eaves portion 32 is protruded by a predetermined amount in the attachment / detachment direction of the dustproof glass 15 (the direction indicated by the arrow A), and the dustproof glass engagement guide portion 16 is opened in the eaves portion 32 as shown in FIG. Fourteen (14) can be formed at intervals in the longitudinal direction.

Each of the dust-proof glass engagement guides 16
Are formed integrally with the cover 13 made of resin. Further, as clearly shown in FIG.
4 is opposite to one side edge 14a (FIG. 1).
On the side, lower dustproof glass engagement guides 33a and 33b are formed integrally with the cover 13 on the front side and the back side in the vicinity of the opening 14.

The eaves 32 formed integrally with the cover 13
Is to prevent the toner falling from above the optical scanning device 3 from adhering to the dust-proof glass 15. When the entire optical scanning device 3 is held, the finger of the handler is held by the eaves portion. There is also an effect of not directly touching the dustproof glass 15. Therefore, it is possible to prevent a decrease in image quality due to the attachment of fingerprints to the dust-proof glass 15.

FIG. 6 is a longitudinal sectional view of the cover shown in FIG. 8 taken along the line BB. As shown in FIG.
The dust-proof glass engaging guides 16 formed at three locations on the cover 13 at intervals along the longitudinal direction are provided with dust-proof glasses 15.
When the dustproof glass 1 is inserted into the cover 13,
The upper part 5 is regulated so as not to escape to the outside (to the right in FIG. 6) and leave the flat part 27.

The cover 13 has a portion other than the portion where the dust-proof glass engagement guide portion 16 is formed, that is, a cross section taken along the line CC shown in FIG. The inner surface 32a of the eave portion 32 is
The escape in the direction of arrow E is restricted. As described above, the cover 13 is provided with the lower dustproof glass engaging guide 33a on the front side in the longitudinal direction (the entrance side where the dustproof glass 15 is inserted) as shown in FIG. The dustproof glass engagement guides 33b are formed integrally with the cover 13, respectively.

Then, the lower dust-proof glass engaging guide portion 3
Reference numerals 3a and 33b denote dust-proof glasses 1 inserted at predetermined positions.
A certain gap is formed between the dustproof glass 15 and the inserted dustproof glass 15 so that the cover 5 does not come off the cover 13. Therefore, the lower dust-proof glass engagement guide portion 33
The a and 33b do not impair the attachment / detachment operation (insertion / extraction operation) of the dustproof glass 15 to / from the cover 13.

By the way, in the optical scanning device in which the optical path of the laser beam passes through the dust-proof glass, the dust-proof glass can be detachably attached with a simple structure so that the toner attached to the dust-proof glass can be cleaned. Then, the method of holding the dust-proof glass becomes a problem.

That is, as shown in FIG. 9, for example, when the dust-proof glass 45 is simply sandwiched and held between the cover 43 and the optical housing 42, each component of another optical scanning system such as a polygon scanner. In order to replace the cover or to remove the cover when cleaning these parts, it is necessary to remove the dust-proof glass 45 from the optical scanning device in advance, but by neglected to remove the dust-proof glass 45 If so, the dust-proof glass 45 falls, and in the worst case, the dust-proof glass 45 may be damaged, or other parts may be damaged.

That is, the configuration shown in FIG.
As shown in FIG. 10, since the configuration is such that the cover 43 is simply sandwiched and held between the dust-proof glass receiving portion 51 of the optical housing 42 and the cover 43, if the cover 43 is removed carelessly, the dust-proof glass 45 There was a risk of falling inside and being damaged.

However, the optical scanning device 3 described with reference to FIGS. 1 to 8 uses the dustproof glass 15 inserted at a predetermined position at the opening edge of the opening 14 of the cover 13 to completely cover the opening 14. Since the dust-proof glass engagement guide portion 16 for closing the cover is formed integrally with the cover 13, the dust-proof glass 15 can be manufactured at a relatively low cost with a simple configuration. In this case, the dustproof glass 15 can be prevented from dropping.

Further, the optical scanning device 3 forms the eaves 32 on the cover 13 as shown in FIG.
Since the dustproof glass engagement guide 16 for detachably engaging and holding the dustproof glass 15 is formed on the lower surface of
The image forming unit 2 is disposed above the optical scanning device 3,
Even if the floating toner or the like falls from the image forming unit 2 onto the optical scanning device 3, the toner is transferred to the dustproof glass 1.
5 hardly adheres.

Therefore, by the function of the eaves 32,
The frequency of cleaning the dustproof glass 15 can be reduced. The laser printer, which is the image forming apparatus described with reference to FIG. 2, includes an optical scanning device 3 on which an operation side for attaching and detaching the dustproof glass 15 to and from the dustproof glass engagement guide portion 16 of the cover 13 (see FIG. 1). It is on the front side of the main body 1 (front side in the figure).

Therefore, when the operation side for attaching and detaching the dustproof glass to and from the optical scanning device is different from the operation surface (standing position) of the image forming apparatus, the dustproof glass is taken out from the optical scanning device and cleaned. In this case, the operator has to move the back and forth of the machine to attach and detach the dust-proof glass. However, according to the optical scanning device 3, the dust-proof glass is not moved from the operation surface of the image forming apparatus. It is easy to clean because it can be attached and detached. In addition, when the dust-proof glass is attached and detached, it is not necessary to move the image forming apparatus to a position where it is easy to clean, so that the dust-proof glass and the like can be efficiently cleaned.

Further, as described with reference to FIG. 5 and the like, when the dust-proof glass 15 is inserted to a predetermined position as shown in FIG. Since the dustproof glass 15 is pressed against the flat portions 27 and 31 by 28 and 29, the dustproof glass 15 is adhered to the flat portion of the cover 13 so as to cover all the openings.

Therefore, the dust-proof glass 15 and the cover 13
Since no gap is formed between the cover 13 and the dust-proof glass 15, dust can be prevented from entering the cover 13 without performing a troublesome seal in order to secure the hermeticity between the cover 13 and the dust-proof glass 15. Therefore, cost increase can be suppressed.

[0039]

As described above, according to the present invention, the following effects can be obtained. According to the optical scanning device of the first aspect, the dust-proof glass is detachably attached to the cover so as to cover all the openings through which the laser light is emitted by the dust-proof glass engagement guide provided on the cover.
Even if the cover is removed without removing the dustproof glass, the fall of the dustproof glass can be prevented. Accordingly, it is possible to prevent the dust-proof glass from being inadvertently damaged.

According to the optical scanning device of the second aspect, since the dust-proof glass engagement guide is formed integrally with the cover, the number of parts is not increased, so that it can be manufactured relatively inexpensively. In addition, maintenance work such as cleaning the dustproof glass can be efficiently performed.

According to the optical scanning device of the third aspect, the dust-proof glass inserted to the predetermined position is brought into close contact with the cover so as to cover the entire opening of the cover by the biasing elastic portion formed integrally with the cover. Further, it is possible to prevent dust from entering the cover without performing a troublesome seal between the cover and the dustproof glass. Therefore, it is possible to prevent a decrease in image quality while being inexpensive.

According to the optical scanning device of the fourth aspect, the eaves portion is protruded by a predetermined amount at a position close to the opening of the cover, so that there is no need to add other components from above the optical scanning device. The falling toner can be received by the eaves so that the toner does not easily adhere to the dustproof glass. Therefore, it is possible to prevent a decrease in image quality caused by toner and dust adhering to the dust-proof glass.

According to the optical scanning device of the fifth aspect, the dust-proof glass engagement guide for engaging and holding the dust-proof glass is provided on one side edge of the opening of the cover and on the other side edge opposite to the one side edge. Since it is formed, the dust-proof glass can be held more reliably.

According to the image forming apparatus of the present invention, the operation side for attaching and detaching the dust-proof glass is located on the front side of the apparatus main body of the image forming apparatus. When removing the printer from the machine, there is no need to move around the machine behind or to the side to attach or detach the dust-proof glass, or move the image forming apparatus to a position that is easy to clean. Downtime can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the vicinity of a dust-proof glass of an optical scanning device according to an embodiment of the present invention, with an optical scanning system in an optical housing not shown.

FIG. 2 is a schematic diagram showing a laser printer which is an image forming apparatus to which the optical scanning device is mounted.

FIG. 3 is an external perspective view showing the optical scanning device in a state where dustproof glass is inserted into a dustproof glass engagement guide to a predetermined position.

FIG. 4 is a perspective view showing the optical scanning device with a cover removed.

FIG. 5 is a cross-sectional view showing a state where dustproof glass is inserted into a cover from a receiving portion to a predetermined position.

FIG. 6 is a vertical sectional view of the cover of FIG. 8 taken along a line BB.

FIG. 7 is a vertical sectional view of the cover taken along a line CC of FIG. 8;

FIG. 8 is a perspective view showing a cover that covers an upper part of the optical scanning device of FIG. 1;

FIG. 9 is a longitudinal sectional view similar to FIG. 1, partially showing an example of an optical scanning device in which dustproof glass is simply held between a cover and an optical housing.

FIG. 10 is a perspective view partially showing only an optical housing provided in the optical scanning device of FIG. 9;

[Explanation of symbols]

 1: Device main body 3: Optical scanning device 12: Optical housing 13: Cover 14: Opening 14a: One side edge 14b: Side edge 15: Dustproof glass 16, 33a, 33b: Dustproof glass engagement guide 27, 31: Flat portion 28, 29: biasing elastic part 32: eaves part

Claims (6)

[Claims] 1. A cover for preventing dust from entering into an optical housing in which an optical scanning system for scanning laser light is housed, and an opening formed on the cover for emitting laser light so as to be closed. A dust-proof glass provided to prevent dust from entering the optical housing from the opening and to form an optical path, wherein the dust-proof glass is attached to and detached from an opening edge of the opening of the cover. A dust-proof glass engaging guide portion is provided so that the dust-proof glass is engaged with the dust-proof glass engaging guide portion so that the dust-proof glass completely covers the opening when the dust-proof glass is inserted to a predetermined position. An optical scanning device, comprising: 2. The optical scanning device according to claim 1, wherein the dust-proof glass engagement guide is formed integrally with the cover. 3. The optical scanning device according to claim 1, wherein the dust-proof glass inserted to the predetermined position on the flat portion near the opening of the cover is urged to close the opening. An optical scanning device, wherein a biasing elastic portion is formed integrally with the cover. 4. The optical scanning device according to claim 1, wherein a position of the cover close to the opening is set along a side edge of the opening in a direction in which the dust-proof glass is attached and detached. An optical scanning device, wherein an eave portion is protruded by a predetermined amount, and the dustproof glass engagement guide portion is formed on the eave portion. 5. The optical scanning device according to claim 4, further comprising a dust-proof glass engaging guide for detachably engaging the dust-proof glass with the other side edge of the cover opening opposite to the one side edge. An optical scanning device formed near the opening. 6. An image forming apparatus in which the optical scanning device according to claim 1 is mounted on an apparatus main body, wherein the dustproof glass is attached to and detached from the dustproof glass engagement guide portion of the cover. An image forming apparatus, wherein an operation side to be operated is disposed on a front side of the apparatus main body.