JP2601248Y2 - Cable member wiring structure of scanning optical system unit - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning optical system unit in which optical components constituting an optical system for scanning a beam in a housing member in a predetermined angular range are arranged and integrated in a predetermined positional relationship. The present invention relates to a wiring structure of a cable member for connecting the cables.

[0002]

2. Description of the Related Art In an apparatus having an optical system in which a plurality of optical components are arranged in a highly accurate relative positional relationship, an optical system unit is constructed by arranging the optical components in one housing member with a predetermined accuracy. In many cases, the optical system unit is configured to be mounted on a chassis of an apparatus using the optical system unit. As described above, by unitizing an optical system configured by combining optical components that need to be mounted in a high-precision relative positional relationship, it is possible to maintain accuracy between the optical components and improve assemblability into an apparatus.

For example, in a laser printer which scans a photosensitive drum with a laser beam modulated based on image forming information and forms an image on a recording sheet by using an electrophotographic method, the laser beam scans the photosensitive drum. As shown in a perspective view in FIG. 7, a laser oscillator (semiconductor laser 21) for emitting a laser beam, a polygon mirror 22, which is a reflection / deflection means for scanning and moving the laser beam emitted from the semiconductor laser 21, An optical component such as an fθ lens 23 for stabilizing the scanning speed and a mirror 24 for guiding the scanning laser beam to a predetermined position is configured as a scanning optical system unit disposed in the housing 10 with a predetermined accuracy.

In a laser printer, since it is necessary to modulate a laser beam in synchronization with the scanning thereof, a light receiving element (laser beam detection sensor 50) for detecting a laser beam at the end of a scanning range which does not contribute to image formation is provided. The laser beam detection signal from the laser beam detection sensor 50 is provided as a horizontal synchronization signal. That is, the scanning position of the laser beam is grasped by the detection of the laser beam by the laser beam detection sensor 50, and the laser beam is modulated based on this to start drawing from a predetermined position on the photosensitive drum. It is.

In order to detect the scanning position of the laser beam with high accuracy, it is desirable to arrange the laser beam detection sensor 50 at an optically equivalent position to the laser beam scanning surface (photosensitive drum surface). A reflection member (laser beam position detecting mirror 25) is disposed at one end of the scanning range, and a laser beam detection sensor 50 is provided outside the other end of the scanning range corresponding to the laser beam position detecting mirror 25. Is arranged so that the scanning laser beam at one end of the scanning range of the laser beam is reflected by the mirror 25 for laser beam position detection and guided to the laser beam detection sensor 50, and reaches the laser beam detection sensor 50. The laser beam path length is set to be substantially equal to the laser beam path length reaching the photosensitive drum surface.

The semiconductor laser 21 is provided inside a collimator housing 26 supporting a collimator lens, and is provided with a laser circuit 41 provided with a drive circuit for driving the semiconductor laser 21 and a light emission stabilization circuit for feedback-controlling the laser output. And fixed to the peripheral wall of the housing 10 via the collimator housing 26. The laser board 41 is located outside the peripheral wall of the housing 10.

On the other hand, the laser beam detection sensor 50 is mounted on a sensor board 42 provided with a synchronization signal detection circuit, and is supported on the outer surface of the peripheral wall of the housing 10 via the sensor board 42. The sensor board 42 is a cable 70
Is connected to the laser substrate 41 through the
Is connected to a control main board of the laser printer (not shown) via a cable 80 so that the semiconductor laser 21 is driven and controlled based on a detection signal from the laser beam detection sensor 50. Sensor board 42
A cable 70 connecting the laser board 41 to the housing 10 is supported by the housing 10 via an attachment member such as a cable clip 90 fixed to the housing 10, and is routed along the outer peripheral wall of the housing 10.

[0008]

However, in the scanning optical system unit constructed as described above, the cable connecting the sensor substrate and the laser substrate as the light source substrate is exposed on the outer surface of the unit. At the time of transportation, assembling and adjustment, the cable is easily caught and there is a risk of disconnection, and the appearance is not good.

[0009]

In view of the above circumstances, the present invention enables rational routing of cables connecting optical components such as a sensor board and a light source board, as well as during transportation, assembly and adjustment. It is an object of the present invention to provide a cable member wiring structure of a scanning optical system unit that can prevent the cable from being caught and a disconnection caused by the cable.

[0010]

In order to achieve the above object, a cable member arrangement structure of a scanning optical system unit according to the first aspect of the present invention comprises a light source for emitting a beam and a reflection for scanning the beam from the light source. A deflecting unit, an fθ lens that stabilizes a scanning speed by the reflective deflecting unit, a beam detection sensor that detects a beam scanned by the reflective deflecting unit, a light source,
A reflection / deflection means, a housing member on which the fθ lens and the beam detection sensor are mounted, and a cable member for electrically connecting the light source and the beam detection sensor is fixed between the fθ lens and the housing member. .
According to a third aspect of the present invention, there is provided a cable member arranging structure for a scanning optical system unit, comprising: a light source for emitting a beam; a reflecting / deflecting unit for scanning the beam from the light source; A support member, an fθ lens that stabilizes a scanning speed by the reflective deflecting unit, a beam detection sensor that detects a beam scanned by the reflective deflecting unit,
A light source, a reflection / deflection means support means, an fθ lens, and a housing member on which the beam detection sensor is mounted, and a cable member for electrically connecting the light source and the beam detection sensor is provided. It is characterized by being fixed between.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a scanning optical system unit to which an embodiment of a cable member wiring structure of the optical system unit according to the present invention is applied. The illustrated scanning optical system unit 1 includes a semiconductor laser 2 for emitting a laser beam at a predetermined position of a housing 10 as a housing member.
1, polygon mirror 22, fθ lens 23, mirror 24
And optical elements such as a laser beam position detecting mirror 25 are fixedly installed with high precision so as to have a predetermined relative distance and a predetermined relative angle, respectively. In addition, although other optical components are actually mounted, they are omitted in the figure.

The housing 10 is formed in a box-like shape with a peripheral wall 12 having a predetermined thickness standing upright at a predetermined height all around the periphery of a flat base 11. Base 11
Has an optical component mounting portion 13, and a laser mounting portion 14 is formed on one peripheral wall 12 on one side. In the vicinity of one end of the optical component mounting unit 13, a polygon mirror 22 that reflects and scans a laser beam emitted from a semiconductor laser 21 described later is arranged.
At the other end, there is provided a mirror 24 that reflects the scanning laser beam and emits the scanning laser beam to the outside of the scanning optical system unit 1 through an emission opening 15 formed at a corresponding portion. Further, an fθ lens 23 is provided in a central area between the polygon mirror 22 and the mirror 24.

The polygon mirror 22 is fixed to a rotating shaft of a driving motor 27, and the driving motor 27 is fixed to the optical component mounting section 13. fθ lens 23
A flat spring 31 (partially shown in the drawing) screwed to the boss 16 erected on the optical component mounting portion 13 presses and fixes the upper surface of the optical component mounting portion 13. The laser mounting portion 14 is formed so that the peripheral wall 12 stands upright at an angle facing the polygon mirror 22 at a right angle, and a semiconductor laser 21 as a light source is mounted here via a collimator housing 26.

The collimator housing 26 has a cylindrical shape having a large-diameter flange, in which the semiconductor laser 21 is provided, and a collimator lens (not shown) is provided in front of the laser beam emission direction. Semiconductor laser 2
1 is mounted on a laser substrate 41 provided with a drive circuit for driving the semiconductor laser 21 and a light emission stabilizing circuit for feedback-controlling the laser output. That is, the semiconductor laser 21 is provided inside the collimator housing and mounted on the laser mounting portion 14 via the collimator housing, and the laser substrate 41 is supported by the semiconductor laser 21.

A mirror 25 for detecting a laser beam position is provided at a predetermined angle on the inner surface of the peripheral wall 12 on the same side where the laser mounting portion 14 is formed, near the mirror 24. The laser beam position detecting mirror 25 is located at the end of the scanning range of the laser beam that scans while being reflected by the reflecting surface of the rotating polygon mirror 22, and makes the laser beam at the end of the scanning range parallel to the mirror 24. It is arranged so as to reflect in the direction in which the light is reflected.

The other peripheral wall 12 corresponding to the laser beam position detecting mirror 25 is provided with a laser beam detecting sensor 50 as a beam scanning position detecting sensor.
The laser beam detection sensor 50 is mounted on a sensor substrate 42 provided with a synchronization signal detection circuit, and is provided on the outer surface of the peripheral wall 12 via the sensor substrate 42. A transmission port 16 is formed in the peripheral wall 12 corresponding to the laser beam detection sensor 50, and the laser beam reflected by the laser beam position detection mirror 25 is transmitted to the laser beam detection sensor 50 through the transmission port 16. It is designed to be incident.

The sensor board 42 and the laser board 41 are connected by a cable 60. That is, the laser substrate 4
1 and a connector 4 on the component mounting side of the sensor board 42, respectively.
1C and 42C are attached,
C, 41C, the routing holes 17,
An opening 18 is formed, and the cable 60 is connected to the routing holes 17 and 1.
8, the connectors 41C and 42C (that is, the laser board 41 and the sensor board 42) are routed substantially linearly.

The wiring route of the cable 60 is the fθ lens 2
3, the cable 60 is positioned between the lower surface of the fθ lens 23 and the upper surface of the optical component mounting unit 13, and is fixed by the fθ lens 23. That is,
The cable 60 is routed inside the optical component mounting section 13 (that is, inside the housing 10), and the fθ lens 23 functions as a cable holder in addition to its original function. As a result, the sensor substrate 42 is
It is not necessary to route the cable 60 to be connected to 1 on the outer surface of the housing 10, so that the length can be minimized, and the cable pressing member is not required.

Here, the cable 6 of the optical component mounting section 13
If the cable guide groove 13A is formed in the routing route 0 as shown in FIG. 2 corresponding to the cross-sectional view taken along the line AA in FIG. 1, the cable 60 affects the installation position accuracy of the fθ lens 23. Can be prevented, and the routing route of the cable 60 can be restricted. In addition, as shown in FIG.
A cable housing groove 23A may be formed on the lower surface of the θ lens 23.

FIG. 4 shows a second embodiment of the present invention, in which the cable 60 is fixed by the drive motor 27 of the polygon mirror 22. Note that the reference numerals in the figure are common to those in the first embodiment. Also in this embodiment, a cable guide groove 13B is formed in the optical component mounting portion 13 as shown in FIG. 5 corresponding to the BB cross-sectional view, and a cable housing is formed in the lower surface of the drive motor 27 as shown in FIG. The groove 27A may be formed.

[0021]

As described above, according to the cable member arranging structure of the scanning optical system unit according to the present invention, it is possible to rationally arrange the cable members for connecting the optical components, and to perform the cable arranging. No pressing member is required, which can contribute to downsizing and cost reduction. Further, it is possible to prevent the cable from being caught during transportation or assembling / adjustment, and to prevent disconnection due to the hooking.

[Brief description of the drawings]

FIG. 1 is a perspective view of a scanning optical system unit to which an embodiment of a cable member wiring structure of the scanning optical system unit according to the present invention is applied.

FIG. 2 is a view corresponding to a cross section taken along line AA of FIG. 1;

FIG. 3 is a view corresponding to a section taken along line AA of FIG. 1;

FIG. 4 is a perspective view of a scanning optical system unit to which another embodiment is applied.

FIG. 5 is a view corresponding to a section taken along line BB of FIG. 4;

FIG. 6 is a view corresponding to a section taken along line BB of FIG. 4;

FIG. 7 is a perspective view of a conventional scanning optical system unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Scanning optical system unit 10 ... Housing (housing member) 21 ... Semiconductor laser (light source) 22 ... Polygon mirror (optical part, reflective deflection means, rotary polygon mirror) 23 ... fθ lens (optical part) 27 ... Drive motor ( Motor) 50: Laser beam scanning position detection sensor (beam scanning position detection sensor) 60: Cable (cable member)

Claims (6)

(57) [Scope of request for utility model registration] 1. A light source for emitting a beam, a reflection / deflection means for scanning a beam from the light source, an fθ lens for stabilizing a scanning speed by the reflection / deflection means, and a detection of the beam scanned by the reflection / deflection means And a housing member on which the light source, the reflection / deflection means, the fθ lens, and the beam detection sensor are mounted, and a cable member that electrically connects the light source and the beam detection sensor. A cable member wiring structure for the scanning optical system unit, wherein the cable member is fixed between the fθ lens and the housing member. 2. A cable member for a scanning optical system unit according to claim 1, wherein a housing groove for housing said cable member is formed in one of said fθ lens and said housing member. Routing structure. 3. A light source for emitting a beam, a reflection / deflection means for scanning the beam from the light source, a reflection / deflection means support member for supporting the reflection / deflection means, and fθ for stabilizing a scanning speed by the reflection / deflection means A lens, a beam detection sensor that detects a beam scanned by the reflection / deflection means, and a housing member on which the light source, the reflection / deflection means support means, the fθ lens, and the beam detection sensor are mounted, A cable member for electrically connecting the light source and the beam detection sensor is fixed between the reflection / deflection means support member and the housing member; a cable member wiring structure of the scanning optical system unit. 4. The scanning optical system unit according to claim 3, wherein an accommodation groove for accommodating said cable member is formed in one of said reflection deflecting means support member and said housing member. Cable member wiring structure. 5. The reflection deflecting means is a rotary polygonal mirror driven to rotate by a motor, and the reflection deflecting means support member has the motor. 2. The cable member wiring structure of the scanning optical system unit according to 1. 6. The beam detection sensor according to claim 1, wherein the beam detection sensor detects that a beam scanned by the reflection / deflection means reaches an end of a scanning range. 2. The cable member wiring structure of the scanning optical system unit according to 1.