JPH0511096U - Scanning optical system protective cover - Google Patents

Abstract

(57) [Abstract] [Purpose] On a scanning unit including a scanning optical system that deflects a scanning light beam to repeatedly perform main scanning on an object to be scanned, and a base on which the scanning optical system is mounted and supported. In the protective cover provided in, the cover is attached to the scanning unit so that the scanning optical system in the scanning unit can be easily adjusted even after the control board or the like is placed on the cover. .. A protective cover 2 is provided with an opening 3 at a desired position in a portion covering an upper part of a scanning optical system, and an opening / closing lid 4 is provided in the opening 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is provided on a scanning unit including a scanning optical system that deflects a scanning light beam to repeatedly perform main scanning on a subject, and a base unit that mounts and supports the scanning optical system. The present invention relates to a protective cover that covers the entire system.

[0002]

[Prior Art]

 Conventionally, a light beam scanning device that deflects and scans a light beam has been widely put into practical use in, for example, a scanning recording device such as a laser printer, a scanning reading device, and the like. In the scanning optical system of such a light beam scanning device, the light beam emitted from the light source is reflected and deflected by an optical deflector such as a rotating polygon mirror and focused by a focusing lens such as an fθ lens to obtain a constant speed. The scanning is performed on the object to be scanned which is sent in the direction (sub scanning direction) perpendicular to the deflection direction (main scanning direction). In addition, the scanning optical system that constitutes the above-described optical beam scanning device and the base that has an opening through which the scanning optical system is mounted and supported and which emits the deflected scanning light beam downward are scanned. A light beam scanning device which constitutes a unit and scans a scanning object is also known.

In such a scanning unit, by providing a protective cover on the unit, dust and dirt may enter the scanning optical system in the unit, and the performance of the scanning optical system caused by the incident light from the outside of the unit. It is designed to prevent the deterioration, the above-mentioned noise when the rotating polygon mirror rotates, and the light beam from leaking to the outside of the unit.

[0004]

[Problems to be solved by the device]

 On the protective cover provided in the above-mentioned scanning unit, a control board for controlling the rotation of the rotary polygon mirror and the light source of the light beam is usually placed together with a wiring cord connecting the control board and the light source. Often. Therefore, if it becomes necessary to adjust the scanning optical system after the scanning optical system is supported on the base of the scanning unit, the cover is attached and the control substrate is placed, the control substrate, etc. It is very troublesome to remove all the components from the cover and then open the cover for adjustment, and then to attach the cover and mount the control board again after adjustment. In addition, if all the covers are removed and adjusted, there is a possibility that unintentional parts (especially optical members) will be touched and the parts will be contaminated. In this case, it is necessary to take care of the dirty parts, which is troublesome.

In view of the above circumstances, the present invention makes it possible to easily adjust the scanning optical system in the scanning unit even after the cover is once attached to the scanning unit and the control board or the like is placed. It is intended to provide a protective cover for an optical system.

[0006]

[Means for Solving the Problems]

 The protective cover of the scanning optical system according to the present invention includes a scanning optical system that deflects a scanning light beam from a light source to repeatedly perform a main scan on an object to be scanned, and a base that mounts and supports the scanning optical system. A protective cover which is provided on the scanning unit consisting of and covers the upper side and the lateral side of the entire scanning optical system. An opening is provided at a desired position of a portion of the protective cover which covers the upper side of the scanning optical system. It is characterized in that it is provided with a lid part that can be opened and closed.

[0007]

[Effect of action and device]

 The protective cover for the scanning optical system according to the present invention is the above-mentioned protective cover for covering the entire scanning optical system above and laterally, and an opening is provided at a desired position of a portion of the protective cover covering above the scanning optical system. In addition, since a lid that can be opened and closed is provided in this opening and the base etc. is placed on the protective cover avoiding this lid, the control base etc. is placed on this protective cover, and then the inside of the scanning unit Even if it becomes necessary to adjust the scanning optical system, it is possible to easily perform the desired adjustment of the scanning optical system without removing the control board or the like.

[0008]

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic plan view of a light beam scanning recording apparatus having a scanning unit using a protective cover of a scanning optical system according to an embodiment of the present invention. In this embodiment, the scanning optical system is supported by the base of the scanning unit 30, a semiconductor laser is used as a laser light source, and a rotary polygon mirror is used as an optical deflector. And a light beam switching mechanism for converting the beam diameter of the light beam. In the present embodiment, the part of the protective cover of the present invention which covers the side of the scanning optical system is integrated with the scanning unit 30.

A scanning light beam 11 emitted from a semiconductor laser 10 which is a first laser light source is collimated by a collimator lens 12 and a beam diameter is changed by a light flux switching mechanism 13 capable of switching a plurality of apertures. After the conversion, it is corrected by the cylindrical lens 14, and the optical path is changed by the reflecting mirrors 15a and 15b, and the reflecting surface 16A of the rotary polygon mirror 16 driven in the arrow direction by a motor (not shown) is irradiated. The rotating polygon mirror 16 is an octahedral rotating mirror that reflects and deflects the light beam, and one reflecting surface scans the light beam once. The scanning light beam 11 reflected and deflected by the rotary polygon mirror 16 passes through a focusing lens 17 such as an fθ lens, and then is focused on a drum (not shown) via a reflecting mirror. Here, the start point and end point of the scanning of the scanning light beam 11 are detected by the start point detector 21 and the end point detector 22, and the semiconductor laser is controlled as a start and end point correction pulse of the semiconductor laser.

Here, the manner in which the optical path of the light beam after passing through the focusing lens 17 is bent will be described with reference to FIG.

FIG. 2 is a sectional view taken along the line II in FIG. 1 of the optical beam scanning recording apparatus having the scanning unit using the protective cover of the scanning optical system according to the embodiment of the present invention. In FIG. 2, only the reflecting means is shown, and other optical systems such as the rotary polygon mirror 16 are omitted.

The scanning light beam 11 incident on the first reflecting mirror 18a is reflected by the first reflecting mirror 18a to change its optical path, and is incident on the second reflecting mirror 18b. By being reflected by the second reflecting mirror 18b, the optical path is changed again and the light enters the concave cylindrical mirror 19. The scanning light beam 11 reflected by the concave cylindrical mirror 19 passes through the opening 26, forms an image at the image forming point C on the drum, is main-scanned in the direction of the arrow X shown in FIG. 1, and the image is reproduced. It

While the scanning light beam 11 scans the photoconductor 27 as described above, the rotation detecting light beam 24 is emitted from the semiconductor laser 23 which is the second laser light source. 24 is reflected and deflected by a reflecting surface 16B different from the reflecting surface 16A of the rotary polygon mirror 16, is reflected by five rotation detecting reflecting mirrors 25a to 25e arranged at equal intervals, and is incident on a detector 26. The detector 26 generates a rotation unevenness correction pulse for the rotary polygon mirror 16 based on the incident rotation detection light beam 24, and the correction pulses detected by the start point detector 21 and the end point detector 22 described above. At the same time, it is output to a control system that rotates the rotary polygon mirror 16, and uneven rotation of the rotary polygon mirror 16 is corrected based on these pulses.

A protective cover for a scanning optical system, which is an embodiment of the present invention, used in the scanning unit 30 of the light beam scanning recording apparatus as described above will now be described with reference to FIGS. 3 and 4.

FIG. 3 is a schematic perspective view of an embodiment of a protective cover for a scanning optical system according to the present invention, and FIG. 4 is a schematic plan view of an embodiment of a protective cover for a scanning optical system according to the present invention.

As shown in FIGS. 3 and 4, the scanning unit 30 is provided with a protective cover 2 according to the present invention, and the protective cover 2 is located at a position corresponding to the light beam switching mechanism 13 of the scanning unit 30. It has an opening 3. The opening 3 is provided with a lid 4 which can be opened and closed by inserting a screw 5 into the screw holes 4a and 2a.

Here, for example, when assembling the scanning unit 30, a protective cover is attached to the scanning unit 30, and a control substrate for controlling the scanning optical system is placed on the protective cover while avoiding the lid 4, and then the light flux switching is performed. If the mechanism 13 needs to be adjusted, the screw 5 is removed and the lid 4 is opened to adjust the light flux switching mechanism 13, so that the control board mounted on the protective cover can be adjusted. The light flux switching mechanism 13 can be adjusted without removing the protective cover 2 and without touching other parts (particularly, optical members) to contaminate the other parts.

In the above embodiment, the lid 4 is provided on the protective cover 2 so as to be openable and closable by the screw 5, but the means for making the lid 4 openable and closable is not limited to the screw. As shown, the lid 4'may be hinged to the protective cover 2'using the hinge 6 so that the lid 4'can be opened and closed.

Further, in the above embodiment, the opening 3 is provided at a position corresponding to the light flux switching mechanism 13 of the protective cover 2, but the opening 3 may be provided at any position, for example, the rotary polygon mirror 16 is provided. For adjustment, it may be provided at a position corresponding to the rotary polygon mirror 16.

Further, in the above embodiment, the opening 3 is provided only at one place, but it is needless to say that any number of openings may be provided if necessary.

Further, although the light beam scanning recording apparatus has been described in the above embodiments, the scanning optical system of the present invention can be applied not only to the scanning recording apparatus but also to the scanning reading apparatus. There is no end.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a light beam scanning recording apparatus having a scanning unit using a protective cover of a scanning optical system according to the present invention.

2 is a sectional view taken along line II in FIG. 1 of a beam scanning recording apparatus having a scanning unit using a protective cover of a scanning optical system according to the present invention.

FIG. 3 is a schematic perspective view of an embodiment of a scanning optical system protective cover according to the present invention.

FIG. 4 is a schematic plan view of an embodiment of a protective cover for a scanning optical system according to the present invention.

FIG. 5 is a schematic perspective view of another embodiment of the protective cover of the scanning optical system according to the present invention.

[Explanation of symbols]

 2, 2'Protective cover 3, 3'Aperture 4, 4 'Lid 10 Semiconductor laser 11 Scanning light beam 12 Collimator lens 13 Luminous flux switching mechanism 14 Cylindrical lens 16 Rotating polygon mirror 18a, 18b Reflector 19 Concave cylindrical mirror

Claims (1)

Claims for utility model registration: 1. A scanning optical system for deflecting a scanning light beam from a light source to repeatedly perform main scanning on an object to be scanned, and a substrate for mounting and supporting the scanning optical system. A protective cover which is provided on a scanning unit composed of a table and which covers the entire scanning optical system above and laterally, an opening is provided at a desired position of a portion of the protective cover which covers above the scanning optical system, A protective cover for a scanning optical system, which is provided with an openable / closable lid part at an opening.