JPH0579524U - Optical beam blocking structure for optical scanning device - Google Patents

Abstract

(57) [Abstract] [Purpose] A shutter that shields a light beam when the opening / closing cover is opened is formed integrally with other parts, and the number of parts and the number of assembly steps are reduced to reduce the cost of the device. In a laser printer in which an opening / closing cover is openably / closably attached to a housing, a protrusion 22 is provided on the housing, and an elastic portion 114 elastically deformable in a thickness direction is integrally formed on a bottom portion 111 of a unit housing 110. Forming,
The leg 1 is attached to the housing-side surface 114b of the elastic portion 114.
16 and a light blocking piece 115 on the opposite surface 114a, and when the opening / closing cover is opened, the leg 116 projects from the projection 22.
When the elastic portion 114 is elastically deformed by being abutted against and pressed against, the light shielding piece 115 advances into the optical path of the scanning light beam B2 in the unit housing 110 to shield it, while the leg body is closed when the opening / closing cover is closed. The elastic member 114 is returned to its original position by separating the protrusion 116 from the projection 22, and the light shielding piece 115 is retracted from the optical path of the scanning light beam B2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a light beam shielding structure in an optical scanning device such as a laser printer.

[0002]

[Prior Art]

 The housing includes a housing and an opening / closing cover attached to the housing so as to be openable and closable. The housing is provided with a photosensitive drum. The opening / closing cover has an optical scanning unit that emits a scanning light beam toward the photosensitive drum. In the provided laser printer, the opening / closing cover is provided with an emission window for emitting the scanning light beam from the optical scanning unit to the photosensitive drum side. By the way, in the laser printer with such a configuration, if the scanning light beam is accidentally emitted from the emission window when the opening / closing cover is opened for maintenance or the like, the scanning light beam may be irradiated to the user's eyes. There is. Therefore, conventionally, a long shutter is swingably provided in the exit window of the optical scanning unit, and the shutter is swung to close the exit window when the opening / closing cover is opened.

[0003]

[Problems to be solved by the device]

 However, in the above-mentioned conventional light-shielding structure, a separate component for closing the exit window of the optical scanning unit when the opening / closing cover is opened is required, so that the number of components and the number of assembling steps increase, and the cost cannot be reduced. There was a problem. Further, in the past, since the scanning light beam scanning-deflected in the emission window was shielded, a long shutter was required according to the length of the emission window, that is, the width of the main scanning range of the scanning light beam. There was a problem that the structure of the shutter was large.

The present invention has been made in view of the above-described problems, and a shutter that shields an optical beam when the opening / closing cover is opened can be formed integrally with other parts, so that the number of parts and the number of assembly steps are increased. It is an object of the present invention to provide an optical beam shielding structure for an optical scanning device, which can reduce the cost and reduce the cost of the device. It is another object of the present invention to provide a light beam blocking structure for an optical scanning device, which can make the shutter structure compact.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a housing, an opening / closing cover that is openably / closably attached to the housing, and a light beam from a light source, which is deflected by a light deflector to scan and deflect the light beam. An optical scanning unit that emits toward a scan target, an optical scanning unit housing that accommodates the optical scanning unit and is attached to one of the housing and the opening / closing cover, the housing, the opening / closing cover, and the optical scanning. It is provided in one of the unit housings, and when the opening / closing cover is closed, it abuts against the housing and one of the opening / closing covers and elastically deforms to allow the light beam to pass therethrough, and when the opening / closing cover is opened, it elastically returns to its original position. A shutter for returning and blocking the light beam is provided. Further, the present invention is configured such that the shutter passes and blocks the light beam between the light source and the light deflector.

[0006]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cutaway perspective view showing a schematic structure of a laser printer adopting a light shielding structure according to a first embodiment of the present invention.

In FIG. 1, reference numeral 10 is a laser printer as an optical scanning device. The laser printer 10 includes a housing 20 and an opening / closing cover 30 that is openably / closably attached to the housing 20. The housing 20 accommodates a printing unit 21 including a photosensitive drum (not shown) to be scanned. The optical scanning unit 100 is attached to the opening / closing cover 30 as shown in FIGS.

As shown in FIG. 3, the optical scanning unit 100 includes a unit housing 110 and a unit cover 120 that closes an opening of the unit housing 110, and as shown in FIG. 1, a bottom portion of the unit housing 110. 111 is attached to the opening / closing cover 30. Then, as shown in FIG. 3, a light source 201 such as a collimator unit that outputs a light beam B1 and a light beam that scans and deflects the light beam B1 emitted from the light source 201 in the main scanning direction N as shown in FIG. A deflector 202, an fθ lens 203 for focusing the scanning light beam B2 scanned and deflected by the optical deflector 202 on a photosensitive drum (not shown) of the printing unit 21, and a scanning light beam B2 transmitted through the fθ lens 203 are provided. A reflection mirror 204 that reflects the light toward the printing unit 21 is provided.

Further, as shown in FIGS. 1 and 3, an emission window 112 for emitting the scanning light beam B2 reflected by the reflection mirror 204 is formed in the bottom portion 111 of the unit housing 110. As shown in FIGS. 4 and 5, the bottom portion 111 is provided with a notch 113 having a substantially U-shaped plan view at a position where the light beam B1 from the light source 201 to the optical deflector 202 faces. An elastic portion 114 that is elastically deformable in the thickness direction of the bottom portion 111 of the unit housing 110 is integrally formed with the bottom portion 111. Further, as shown in FIG. 4, a light shielding portion 115 is erected on a surface 114a of the elastic portion 114 facing the inner side of the unit housing 110, and a leg body 116 is vertically erected on an opposite surface 114b. ing. In this embodiment, the elastic portion 114, the light shielding portion 115, and the legs 116 form a shutter.

On the other hand, as shown in FIG. 2, the opening / closing cover 30 is formed with a through hole 31 for allowing the leg body 116 to project toward the housing 20, and as shown in FIG. A window 32 having substantially the same shape as the exit window 112 is formed at a position where the window 112 faces. Further, as shown in FIGS. 1 and 2, the housing 20 is provided with a protrusion 22 at a position where the leg body 116 faces when the opening / closing cover 30 is closed. As shown in FIG. An arcuate concave portion 22a with which the tips of the legs 116 can come into contact is formed.

In the laser printer 10 having such a configuration, when the opening / closing cover 30 is opened, the leg body 116 is separated from the concave portion 22a of the protrusion 22 and the elastic portion 114 is not elastically deformed as shown in FIG. Since it is at the original position, as shown in FIG. 4, the light shielding portion 115 shields the light beam B1 from the light source 201 to the light deflector 202, and prevents the emission of the scanning light beam B2 from the emission windows 112 and 32.

On the other hand, when the opening / closing cover 30 is closed, first, as shown in FIG. 7, the tips of the legs 116 come into contact with the recesses 22a of the protrusions 22, and when the opening / closing cover 30 is further closed, as shown in FIG. The elastic portion 114 is elastically deformed in the inward direction of the unit housing 110, and the light beam B1 output from the light source 201 is reflected by the elastic portion 114, the legs 116, and the bottom portion 111 of the unit housing 110 as shown in FIG. The light passes through the defined space D and reaches the optical deflector 202. Therefore, when the opening / closing cover 30 is closed, the scanning light beam B2 is emitted from the emission windows 112 and 32 toward the printing portion 21 of the housing 20.

When the opening / closing cover 30 is opened from the state shown in FIG. 8, the elastic portion 114 returns to the original position shown in FIG. 6 due to the elastic force, the light beam B1 is shielded again by the light shielding portion 115, and the exit window 112 is opened. , 32 are prevented from emitting the scanning light beam B2.

As described above, according to the light shielding structure of the present embodiment, the scanning light beam B2 is emitted from the emission window 112 of the unit housing 110 to the window 32 of the opening / closing cover 30 according to the opening / closing of the opening / closing cover 30. Or a shutter for emitting the scanning light beam B 2 from the emission windows 112 to 32, that is, the elastic portion 114, the light shielding portion 115, and the leg body 116 are integrally provided on the bottom portion 111 of the unit housing 110. Therefore, it is possible to eliminate the need for separate parts as in the conventional case, and it is possible to reduce the number of parts and the number of assembling steps and thereby reduce costs. Further, the elastic portion 114 elastically deforms or elastically returns to the original position according to the opening / closing of the opening / closing cover 30, and the light shielding portion 115 advances into the optical path of the light beam B 1 from the light source 201 to the optical deflector 202. Alternatively, since the light is retracted from the optical path, the structure can be made more compact than the conventional structure in which the emission window is opened and closed by a long shutter according to the width of the main scanning range of the scanning light beam.

The shapes of the elastic portion 114, the light shielding portion 115, the legs 116, and the protrusions 22 are not limited to those shown in this embodiment, and for example, the second embodiment of the present invention shown in FIGS. 9 and 10. As described above, a light-shielding portion 117 protruding from the bottom portion 111 of the unit housing 110 to both inside and outside is provided at the tip of the elastic portion 114, and a semicircular recess 117a is formed in the lower portion of the light-shielding portion 117, while the housing is formed. It is also possible to provide a protrusion 23 on the 20 side and form a semicircular recess 23 a in the upper portion of the protrusion 23.

According to this configuration, when the opening / closing cover 30 is opened, as shown in FIG. 9, the light blocking portion 117 blocks the light beam B1 between the light source 201 and the light deflector 202, and the emission windows 112 to 112. The emission of the scanning light beam B2 from the window 32 is blocked. On the other hand, when the opening / closing cover 30 is closed, as shown in FIG. 10, the projection 23 comes into contact with and is pressed against the light shielding portion 117, and the elastic portion 114 is elastically deformed inside the unit housing 110, and the recess 117a of the light shielding portion 117 is formed. The circular through hole E 1 is defined by the concave portion 23a of the projection 23. Then, the light beam B1 output from the light source 201 passes through the through hole E, reaches the optical deflector 202, and the scanning light beam B2 is emitted from the emission windows 112 to 32 toward the printing unit 21 of the housing 20. ..

In addition, as in the third embodiment of the present invention shown in FIGS. 11 and 12, the elastic portion 114 is bent to the outside of the bottom portion 111 of the unit housing 110, and the elastic portion 114 has a tip end. It is also possible to provide a light shielding portion 118 that protrudes inside the unit housing 110, form a semicircular recess 118a in the lower portion of the light shielding portion 118, and provide a protrusion 24 on the housing 20 side.

According to this configuration, when the opening / closing cover 30 is opened, as shown in FIG. 11, the light blocking unit 118 blocks the light beam B 1 between the light source 201 and the light deflector 202, and the exit windows 112 to 112. The emission of the scanning light beam B2 from 32 is blocked. On the other hand, when the opening / closing cover 30 is closed, as shown in FIG. 12, the projection 24 abuts and is pressed against the light shielding portion 118, and the elastic portion 114 is elastically deformed inside the unit housing 110, and the recess 118a of the light shielding portion 118 is formed. To the optical path of the light beam B1 output from the light source 201. Then, the light beam B1 passes through the recess 118a and reaches the optical deflector 202, and the scanning light beam B2 is emitted from the emission windows 112 to 32 toward the printing unit 21 of the housing 20.

By the way, in the structure of the second embodiment, the elastic portion 114 and the light shielding portion 117 form a shutter, and in the structure of the third embodiment, the elastic portion 114 and the light shielding portion 118 form a shutter. Is forming. The same effects as those of the first embodiment can be obtained by the configurations of the second and third embodiments, and in particular, according to the configuration of the third embodiment, the elasticity is increased as the opening / closing cover 30 is closed. When the portion 114 is elastically deformed, the hole formed in the bottom portion 111 of the unit housing 110 due to the formation of the notch 113 is substantially closed by the elastically deformed elastic portion 114 and the light shielding portion 118, and the unit housing 110. It is possible to prevent unnecessary leakage of light from the outside, and it is possible to minimize intrusion of dust and the like into the unit housing 110 during normal operation.

In each of the above embodiments, the elastic portion 114, the light shielding portions 115, 117 and 118, and the leg body 116 are provided in the unit housing 110. However, these are provided in the opening / closing cover 30. The unit housing 110 may be provided with a through hole for letting at least the light shielding portions 115, 117, 118 into and out of the optical path of the light beam B1.

In each of the above-described embodiments, the case where the optical scanning unit 100 is provided on the opening / closing cover 30 has been described. However, a protrusion is provided on the opening / closing cover 30 and an elastic portion is provided on the unit cover 120 of the optical scanning unit 100. The present invention can be applied to an optical scanning device in which the light scanning unit 100 is provided in the housing 20 by forming the light shielding portion (and the leg). Further, in each of the above embodiments, the light shielding portions 115, 117, 118 shield the light beam B1 between the light source 201 and the light deflector 202 when the opening / closing cover 30 is opened. A portion is provided between the optical deflector 202 and the fθ lens 203 or between the fθ lens 203 and the reflection mirror 204, and when the opening / closing cover 30 is opened, the light shielding portion makes the scanning light beam B2 the entire width in the main scanning direction N. It may be configured so as to shield the light.

In each of the above embodiments, a laser printer was described as an example of the optical scanning device, but the light shielding structure of the present invention can be applied to other image scanners, laser photoplotters, and the like. Of course.

[0023]

[Effect of the device]

 As described above, according to the present invention, the light scanning unit is an optical scanning unit that scans and deflects a light beam from a light source with an optical deflector and emits the scan-deflected light beam toward a scan target. This optical scanning unit housing is elastically deformed by abutting against one of the housing and the opening / closing cover when the opening / closing cover is closed in the housing and the optical scanning device attached to the housing so as to be openable / closable. A shutter that allows the light beam to pass therethrough and elastically returns to the original position when the opening / closing cover is opened to block the light beam is provided in one of the housing, the opening / closing cover, and the optical scanning unit housing. Therefore, the shutter can be integrally formed in one of the housing, the opening / closing cover, and the housing for the optical scanning unit, and a separate light-shielding component is not required, so that the number of components and the number of assembly steps can be reduced and the cost can be reduced accordingly. be able to. Further, according to the present invention, since the shutter passes the light beam and blocks the light beam between the light source and the light deflector, the scan-deflected light beam has a wide main scanning range. The shutter can have a more compact structure than the structure in which light is blocked by a shutter of a corresponding size.

[Brief description of drawings]

FIG. 1 is a fragmentary perspective view showing a schematic configuration of a laser printer adopting a light shielding structure according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the laser printer of FIG.

3 is an exploded perspective view showing a schematic configuration of an optical scanning unit provided in the laser printer of FIG.

FIG. 4 is a perspective view of an essential part showing the light shielding structure of the first embodiment of the present invention with the opening / closing cover of the laser printer opened.

FIG. 5 is a perspective view of an essential part showing the light shielding structure of the first embodiment of the present invention with the opening / closing cover of the laser printer closed.

6 is an explanatory diagram showing a positional relationship between legs and protrusions of the light shielding structure of FIG. 4 in a state where an opening / closing cover of the laser printer is opened.

FIG. 7 is an explanatory diagram showing a positional relationship between legs and protrusions of the light shielding structure of FIG. 4 in a state where the opening / closing cover of the laser printer has started to be closed.

FIG. 8 is an explanatory diagram showing a positional relationship between legs and protrusions of the light shielding structure of FIG. 4 in a state where the opening / closing cover of the laser printer is closed.

FIG. 9 is a perspective view of a main part of a light shielding structure according to a second embodiment of the present invention in a state where an opening / closing cover of the laser printer is opened.

FIG. 10 is a perspective view of a main part of a light shielding structure according to a second embodiment of the present invention with the opening / closing cover of the laser printer closed.

FIG. 11 is a perspective view of a main part of a light shielding structure according to a third embodiment of the present invention in a state in which an opening / closing cover of the laser printer is opened.

FIG. 12 is a perspective view of an essential part showing a light shielding structure of a third embodiment of the present invention in a state where an opening / closing cover of the laser printer is closed.

[Explanation of symbols]

10 Laser Printer (Optical Scanning Device) 20 Housing 30 Open / Close Cover 100 Optical Scanning Unit 110 Housing for Unit (Housing for Optical Scanning Unit) 114 Elastic Part (Shutter) 115, 117, 118 Shading Part (Shutter) 116 Leg (Shutter) B1 light beam B2 scanning light beam (light beam)

Claims (2)

[Scope of utility model registration request] 1. A housing, an opening / closing cover attached to the housing so as to be openable and closable, and a light beam from a light source is scanned and deflected by an optical deflector, and the light beam thus scanned and deflected is directed toward a scan target. An optical scanning unit that emits light, an optical scanning unit housing that accommodates the optical scanning unit and is attached to one of the housing and the opening / closing cover, and one of the housing, the opening / closing cover, and the optical scanning unit housing. When the opening / closing cover is closed, it abuts on one of the housing and the opening / closing cover and elastically deforms to allow the light beam to pass therethrough. When the opening / closing cover is opened, the light beam is elastically returned to its original position to shield the light beam. A light beam shielding structure for an optical scanning device, comprising: a shutter. 2. The light beam blocking structure of the optical scanning device according to claim 1, wherein the shutter passes and blocks the light beam between the light source and the light deflector.