JP3471902B2 - Light source device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a laser light source device for use in an image forming apparatus or the like.

[0002]

2. Description of the Related Art Conventionally, as a light source device used in a laser beam scanning optical device applied to an electrophotographic image forming apparatus such as a printer, a copying machine, a facsimile apparatus, etc.
As disclosed in Japanese Patent Laid-Open No. 5-43577, when a second support member having a laser light emitting element is mounted on the back surface of a first support member having a collimator lens, the optical axis of the collimator lens is adjustable. On a horizontal plane including the first support member and having a through hole that is loosely fitted to the outer periphery of the support cylinder of the collimator lens, and the surface of the second support member has a cross section. While a pair of right and left swinging and aligning balls are inserted through the V-shaped conical groove, the first lens is placed on the vertical plane including the optical axis of the collimator lens.
The base plate and the second support member are undetachably connected to each other via a pair of upper and lower adjusting screws protruding from the back surface of the support member and a screw with a pressing spring.

Then, with the screw with the pressing spring loosened to some extent, the position of the substrate together with the second supporting member is appropriately moved in the X direction (horizontal direction) and the Y direction (vertical direction) so that the first supporting member is moved. A technique is disclosed in which after adjusting the position with respect to the back surface, the screw is tightened and fixed so that the optical axis of the collimator lens and the emission center axis of the laser light emitting element are aligned with each other.

[0004]

However, in the structure described in the above publication, the through hole of the substrate is located substantially at the center of the area of the second supporting member and is located at a position covered by the second supporting member. Therefore, when the substrate and the second support member are moved in, for example, the X direction (horizontal direction) by the fine adjustment screw in the jig when adjusting the optical axes, the first support member side with respect to the through hole of the substrate is provided. The relationship between the direction in which the gap between the collimator lens and the outer circumference of the support tube becomes narrower and the direction in which the optical axis deviates (or the relationship between the direction in which the gap expands and the direction in which the optical axis coincides) cannot be immediately confirmed, and the optical axes coincide. There is a problem that it takes a lot of time to make adjustments.

The present invention has been made to solve this problem, and an object of the present invention is to provide a scanning optical device which improves productivity and is inexpensive to manufacture.

[0006]

In order to achieve the above object, a light source device according to a first aspect of the present invention comprises a block body having a collimating lens, one end of an optical path of which is opened on the back surface, and a laser light emitting element. A light source device comprising a mounted laser holder plate, wherein the laser holder plate is moved along the back surface of the block body in the XY directions on the back surface and fixed by screw fastening. , A regulating projection is provided on the back surface of the block body at right angles to the XY directions.
The laser holder plate has a restricting side surface facing the outer peripheral side surface of the restricting projection with an appropriate gap, and is opened to the side edge of the laser holder plate.
By forming as described above, the penetration regulating groove is formed so that the gap can be visually recognized from the outer portion on the side surface side of the block body .

According to a second aspect of the present invention, in the light source device according to the first aspect, the block body is provided with a
A first regulating protrusion is provided on the side edge of the back surface along the X direction.
On the other hand, a second regulating projection is provided on the side edge of the rear surface along the Y direction.
In the laser holder plate, the first regulating protrusion and
First penetration regulation at positions corresponding to the second regulation projections, respectively.
The groove and the second penetration regulating groove are formed.

[0008]

EXAMPLES Next, examples embodying the present invention will be described. FIG. 1 is a schematic sectional side view of a laser beam printer 1 as an image forming apparatus, FIG. 2 is a sectional side view of a scanning optical device, and FIG. 3 is a bottom view showing an arrangement relationship of components inside a housing case 30.

In the printer 1 of this embodiment, a paper feed cassette 3 as a paper feed unit is detachably mounted on one side of the main body case 2 and the paper feed roller 4 and the separation pad 5 are used to keep the inside of the paper feed cassette 3 inside. Paper P as a recording medium stacked on the sheet
Are separated one by one and sent to the image forming unit 9 via the pair of feeding rollers 6.

The image forming unit 9 includes a rotating photosensitive drum 7 as a photosensitive member and a transfer roller 8 as a transfer means.
In the case, a developing device unit 12 including a toner cartridge 10 and a developing roller 11 located near the paper feed cassette 3 side, a charging device 13 on the lower surface side of the photosensitive drum 7, a cleaning device 14 and the like are included in a kit. Stored in a single unit.

A fixing device 17 including a pressing roller 15 and a heating roller 16 is arranged on the discharge side of the image forming unit 9.

Below the image forming unit 9, a peripheral wall 30b of a downward open box-shaped housing case 30 in a scanner unit 18 as a scanning optical device for scanning a laser beam toward the lower surface of the photosensitive drum 7.
Is placed on the upper surface of the flat plate portion 2b of the main frame 2a of the main body case 2 with the top plate 30a facing upward via a sealing material 42 such as a sponge material.
Tie bars 40, 4 attached to the top surface of the top plate 30a
The main frame 2a is detachably attached to the left and right sides of the main frame 2 via the connector 1.

Then, a laser emitted from a scanner unit 18 to be described later on the surface of the photosensitive drum 7 which has been precharged by the charging device 13 in accordance with image data transmitted from an external device such as a host computer (not shown). An electrostatic latent image is formed on the surface (image forming surface) of the photoconductor drum 7 by forming an image of light, and then the developing roller 11 is rotated to supply the charged powdery toner to the latent image. After the development for converting the toner image into a visible image is performed, the toner image is transferred onto the sheet P supplied to the transfer portion between the photosensitive drum 7 and the transfer roller 8, and then the heating in the fixing device 17 is performed. After passing between the roller 16 and the pressing roller 15, heat and pressure are applied to the transferred toner image to fix the toner image on the paper P. After that, the paper is discharged to the paper discharge tray 63 via the paper discharge roller pair 62.

A high voltage substrate 61 for applying a high voltage to the control substrate 60, the charging device 13 and the transfer roller 8 is arranged below the main frame 2a.

Next, the structure of the scanner unit 18 will be described with reference to FIGS. FIG. 3 corresponds to FIG.
It is a III-III line arrow line view, and is a bottom view which observed the inside of the housing case 30 which is a downward open box type and is made of glass reinforced plastic mixed with short glass fibers.

In the scanner unit 18, a laser emitting unit 20 as a light source device, a rotary polygon mirror 27 as a deflector, an fθ lens 21, a cylindrical lens 22, a folding mirror 23, a writing position signal (BD) mirror 25, and a slit. The components including the body 35, the condensing lens 36, the writing position signal detection (BD) sensor 26 such as the light receiving element, and the like are the downward open box type housing case 30.
It is configured by being fixed to the inner surface (lower surface) of the top plate 30a.

Next, the structure of the laser emitting unit 20 as a light source device will be described with reference to FIGS.

Laser emitting unit 2 as a light source device
As shown in FIGS. 4 and 5, the block body 28 at 0 is configured as an optical passage 45 in which the inner diameter of the tubular portion 28a penetrates from the front surface to the rear surface, and is inserted into the optical passage 45 so that the front-back position can be adjusted. A slit plate 47 having a horizontally long slit 47a is attached to the front end side of the cylindrical lens cell 46, and a collimator lens 48 is attached to the rear end of the lens cell 46, and the slit plate 47 and the collimator lens are attached. An optical path 46a communicates with the optical fiber 48.

As will be described later, at the substantially central position of the wide surface of the substantially rectangular laser holder plate 49, which is brought into contact with the back surface of the block body 28 and adjusted after adjusting the optical axis,
A mounting hole 50 is provided. In the mounting hole 50, a laser light emitting element 51 such as a semiconductor laser is attached to the head 5 thereof.
A jig 52 (see FIG. 10) described later is used to fit the collimator lens 48 so that the lens 1b faces the collimator lens 48 in advance.
A plurality of (three in the embodiment) lead terminals 51a of the laser light emitting element 51 are attached to the printed wiring board 29 which is attached to the back surface of the laser holder plate 49 via fastening screws 53 with spring washers 53. It is fixed with solder (see FIGS. 6, 8 and 9).

After moving the lens cell 46 so that the collimating lens 48 is focused on the light emitting point of the laser light emitting element 51 of the laser holder plate 49, an adhesive agent is applied to the cutout portion 28b of the tubular portion 28a. The lens cell 46 is fixed.

When the laser emitting element 51 is mounted so that the axis of the mounting hole 50 orthogonal to the wide surface of the laser holder plate 49 and the optical axis of the laser emitting element 51 are parallel to each other. The mounting hole 50 in 49 is formed by precision punching with a fine blanking press to have a diameter slightly smaller than the outer diameter of the disc-shaped base portion 51c of the laser light emitting element 51 so as to be a tight fit described later. . On the other hand, as shown in FIG. 10, the flat jig 52 has a head 51 b of the laser light emitting element 51.
On the outer periphery of the hole 52a in which the
A support protrusion 52b is formed to abut the end surface of 1c.

Next, the laser holder plate 49 is placed on the upper surface of the jig 52 so that the support protrusion 52b fits into the mounting hole 50 of the laser holder plate 49, and the laser holder plate 49 is mounted from the rear side. The head portion 51b and the base portion 51c of the laser light emitting element 51 are inserted into the mounting hole 50 in the hole 50, the lead terminals 51a of the laser light emitting element 51 are loosely fitted from the back side of the base portion 51c, and the back surface of the base portion 51c is fixed. A pressing jig 5 having an annular pressing portion 54a for pressing
At 4, the support protrusion 52b is pushed in.

As a result, the head 5 of the laser light emitting element 51 is
The optical axis 55 of the laser light beam L emitted from the surface 1b and the surface of the laser holder plate 49 are attached so as to be orthogonal to each other.

Next, a description will be given of position adjustment so that the optical axis of the collimator lens 48 in the block body 28 and the optical axis of the laser light emitting element 51 in the laser holder plate 49 coincide with each other.

As shown in FIGS. 5 to 7, the block body 28
On the rear side of the back side, a first regulating projection 56 having a substantially square shape in a front view is provided so as to project rearward at an upper edge thereof, and a second regulating projection 57 having a substantially concave shape in a front view is provided so as to project rearward at a lower edge thereof. . On the other hand,
The laser holder plate 49 is open to the upper and lower edges thereof, and the first regulating projection 56 and the second regulating projection 5 are provided.
7 to the outer peripheral side surface of each of the outer peripheral side surfaces (in the embodiment,
Gap Δy1, Δy2, Δx1, Δx2, Δx described later
3, Δx4 are each set to about 0.5 mm) and have first and second through-hole restricting grooves 58 and 59, which are notched in a substantially rectangular shape in a front view and have restricting side surfaces facing each other.
And.

With this configuration, the tightening screws 53 with spring washers 53, 53 are formed on the rear surface of the block body 28 through the loose fitting holes 64, 64 formed in the laser holder plate 49, at the positions of the female screws 65, 65. When tightening the laser holder plate 49, the printed wiring board 29 is previously mounted on the back side of the laser holder plate 49, and the laser holder plate 49 is loosened with the tightening screws 53, 53, as shown in FIGS. It is attached to the back surface of the block body 28. At this time, the edge of the printed wiring board 29 is formed so as not to be completely covered by the first penetration restricting groove 58 and the second penetration restricting groove 59.

Then, a laser light beam L is emitted from the laser light emitting element 51 by setting a predetermined light intensity by a power supply circuit (not shown), and collimating is performed by a measuring device (not shown) installed in front of the block body 28. In order that the optical axis of the lens 48 and the optical axis of the laser light beam L from the laser light emitting element 51 may coincide with each other, the laser holder plate 49 may be formed in a jig not shown in the X-axis direction and the Y-axis direction in FIGS. 6 and 7. Use the fine adjustment screw to move a minute distance.

In this case, when the laser holder plate 49 is moved in the upward direction of the paper surface (Y direction) in FIG. 7, the upward restricting side surface of the first penetration restricting groove 58 in the laser holder plate 49 and the first restricting side of the block body 28. The gap Δy1 with the downward regulation side surface of the regulation projection 56 becomes smaller, and finally the movement in that direction is regulated at the place where both regulation side surfaces contact.
Similarly, when the laser holder plate 49 is moved downward in the plane of FIG. 7 (opposite Y direction), the laser holder plate 49 is moved.
The gap Δy2 between the downward regulation side surface of the second penetration regulation groove 59 in and the upward regulation side surface of the second regulation projection 57 in the block body 28 becomes small, and finally the movement in that direction at the point where both regulation side surfaces abut. Regulated. Moreover,
Since there are a total of three places, that is, the downward regulation side surface of the first regulation projection 56 and the two upward regulation side surfaces of the second regulation projection 57, when these points are brought into contact with each other substantially at the same time, the laser holder is practically used. The rotation of the plate 49 about the axis perpendicular to the plane of FIG. 7 is also restricted.

Similarly, when the laser holder plate 49 is moved rightward or leftward (X direction and anti-X direction) on the paper surface of FIG. 7, the first penetrating restriction groove 58 of the laser holder plate 49 is directed rightward (or leftward). ) The clearance Δx1 between the restriction side surface and the left (or right) restriction side surface of the first restriction projection 56 of the block body 28 is small (or the clearance Δx2 is large). Similarly, a gap Δx between the rightward (or leftward) regulating side surface of the second penetration regulating groove 59 in the laser holder plate 49 and the leftward (or rightward) regulating side surface of the second regulating projection 57 in the block body 28.
3 becomes smaller (or the gap Δx4 becomes larger), and finally the movement in that direction is regulated at the position where both regulating side surfaces come into contact. Moreover, when the laser holder plate 49 is moved to the right or left, there are a total of two leftward (rightward) restricting side faces of the first restricting projection 56 and the second restricting projection 57 at positions vertically separated from each other on the block body 28. Since they exist, when they come into contact with these portions at substantially the same time, the rotation of the laser holder plate 49 about the axis perpendicular to the plane of FIG. 7 is also restricted.

Since one of the outer peripheral side surfaces of the first restricting projection 56 and the second restricting projection 57 provided on the back surface of the block body 28 is exposed toward the side surface of the block body 28, Even if the printed wiring board 29 is arranged on the back side of the laser holder plate 49, the first penetration regulation as a notch regulation groove for the first regulation projection 56 (second regulation projection 57) depending on the operating direction of the fine movement screw. The relationship between the direction in which the gap of the groove 58 (the second penetration regulating groove 59) becomes smaller and the Y direction (X direction) in which the optical axis measured by the measuring device deviates (or the Y direction in which the direction in which the gap widens and the optical axis coincide) (Relationship with (X direction)) can be immediately confirmed (visually recognized), and the protrusion for regulation can be moved by a short distance when the optical axis of the laser light emitting element 51 deviates from the optical axis of the collimator lens 48 in the wrong direction. And through-regulation groove and Abuts, more because to become impossible the fine drive operation in the same direction, can be immediately able to perform an adjustment in the opposite direction (right direction), to reduce the time loss of the adjustment.

It should be noted that the first restricting projection 56 is attached to the block body 2
8 is provided on the rear surface of the side edge along the X direction, while the second
The restriction projection 57 is provided on the side edge along the Y direction, and the first penetration restriction groove 58 (the second penetration restriction groove 5) on the laser holder plate 49 side is provided.
9) may be formed at corresponding positions.

Further, as a reference example , the optical path 45 of the collimating lens 48 is provided on the back surface of the block body 28.
A regulation protrusion (not shown), such as a column, is provided rearward at a portion distant from the opening in the outer radial direction, while the laser holder plate 49 has an appropriate gap with the outer peripheral side surface of the regulation protrusion. A through-regulation groove (not shown) having a hole is formed.
In this case, the printed wiring board 29 attached to the back surface of the laser holder plate 49 is provided with a large hole so that the entire penetration regulating groove can be visually recognized. There may be a plurality of pairs of the restriction protrusion and the penetration restriction groove.

A rotary polygon mirror 27 such as a six-sided mirror that rotates in the direction of arrow A in FIG. 3 by a drive motor 31 fixed to the inner surface of the top plate 30a faces the mirror surface of the laser emitting unit. The optical axis incident from 20 is arranged so as to be substantially parallel to the rotation axis of the photosensitive drum 7.
Light beam L reflected by the mirror surface of the rotating polygon mirror 27
Is attached to the top plate 3 at both ends via mounting springs made of leaf springs.
After passing through the fθ lens 21 and the cylindrical lens 22 fixed to 0a, the light is reflected by the folding mirror 23 toward the lower surface of the photosensitive drum 7. Top plate 30 of housing case 30
In a, a long window hole 34 is formed in a portion near the lower surface of the photoconductor drum 7 in parallel with the axis of the photoconductor drum 7, and a light transmissive material such as a glass plate covering the window hole 34 is formed. Through the cover plate 24, the deflected light beam L is scanned on the lower surface of the photoconductor drum 7 along the axial direction of the photoconductor drum 7.

The optical path from the rotary polygon mirror 27 side to the writing position signal mirror 25 provided near one end of the folding mirror 23 in the longitudinal direction, and the slit reflected by the writing position signal mirror 25. The optical path leading to the body 35, the condenser lens 36, and the writing start position signal detection sensor 26 is separated by a partition wall 43, and only the light beam L reflected by the writing start position signal mirror 25 is directed to the slit body 35 and the condenser lens. 36 and the write start position signal detection sensor 26.

A laser driving electronic circuit board (printed wiring board) 37 for processing the horizontal synchronizing signal input to the writing position signal detecting sensor 26 including a light receiving element such as a photodiode to drive the laser emitting unit 20. Is covered from the release surface side of the housing case 30, brought into contact with a rib protruding downward from the inner surface of the top plate 30a or the end surface of the partition wall 43, and fixed to a predetermined hole with a screw 38.

It is needless to say that the present invention can be applied to a scanning optical device in an electrophotographic image forming apparatus such as a facsimile or a copying machine, and other optical devices used for image processing and the like.

[0037]

As described above, claim 1
A light source device according to the invention described above is a light source device including a block body having one end of an optical path provided with a collimator lens and having a rear surface opened, and a laser holder plate to which a laser light emitting element is attached. Along the back surface, the laser holder plate is configured to move in the XY direction on the back surface and fixed by screw fastening, while a restricting projection is provided on the back surface of the block body at right angles to the XY directions. The laser holder plate is formed so as to project rearward and has a regulation side surface facing the outer peripheral side surface of the regulation projection with an appropriate gap and opened to the side edge of the laser holder plate.
By doing so, a penetration regulating groove is formed so that the gap can be visually recognized from the outside on the side surface side of the block body .

Therefore, according to the present invention, the laser holder plate
Also it is attached et overlapping other parts on the back of the laser
The restriction groove formed on the side edge of the holder plate and the restriction on the block body side.
The gap with the control protrusion is exposed on the side of the block body.
Therefore, when adjusting the optical axis of the collimator lens and the optical axis of the laser light emitting element so that they coincide with each other, the relationship between the direction in which the gap of the penetration regulating groove with respect to the regulating projection becomes smaller and the optical axis measured by the measuring device deviates ( Or the relationship that the optical axis coincides with the direction in which the gap expands) is the outer side of the block body.
It can be confirmed (visually recognized) immediately from the section, and when adjusting the wrong direction in which the optical axis of the laser light emitting element deviates from the optical axis of the collimator lens, the restriction projection and the penetration restriction groove come into contact with each other by a short distance movement. Since the fine adjustment screw cannot be operated in the same direction any more, the adjustment in the opposite direction (correct direction) can be immediately performed, and the loss time of the adjustment can be reduced.

According to a second aspect of the present invention, in the light source device according to the first aspect, the restricting protrusion is formed on the block body.
On the back side, the first regulating protrusion is provided on the side edge along the X direction of the back side.
A second ruler is provided on the side edge of the back surface along the Y direction while providing the upright.
A control protrusion is provided, and the laser holder plate is provided with the first rule.
At positions corresponding to the control protrusion and the second regulating protrusion, respectively.
A first penetration restricting groove and a second penetration restricting groove are formed.
Therefore, in addition to the action and effect of the invention according to claim 1 , side edges in the X direction and Y direction on the back surface of the block body.
The effect is that it is extremely easy to visually recognize the edge from outside in two directions .

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of a laser printer.

FIG. 2 is a side sectional view of a scanning optical device.

FIG. 3 is a view taken along the line III-III in FIG.

FIG. 4 is a vertical cross-sectional view of the laser emitting unit shown in FIG. 3 taken along the line IV-IV.

FIG. 5 is a perspective view of each component of the laser emitting unit viewed from the front side.

FIG. 6 is a perspective view seen from the rear side of each component of the laser emission unit.

FIG. 7 is a rear view of the block body.

FIG. 8 is a plan view of the laser emitting unit with a printed wiring board attached.

9 is a view taken along the line IX-IX in FIG.

FIG. 10 is a cross-sectional view showing an operation of attaching a laser light emitting element to a laser holder plate.

[Explanation of symbols]

1 printer 18 Scanner unit 20 Laser emission unit 28 blocks 29 Printed wiring board 30 housing case 37 Electronic Circuit Board 45 optical passage 46 lens cell 47 slit plate 48 collimating lens 49 Laser holder plate 50 mounting holes 51 Laser emitting element 56 First regulating projection 57 Second regulating projection 58 First Penetration Restriction Groove 59 Second Penetration Restriction Groove

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/44 G02B 26/10 G03G 15/04 H01S 3/101

Claims (2)

(57) [Claims] 1. A light source device comprising a block body provided with a collimating lens and having one end of an optical path opened on the back surface thereof, and a laser holder plate having a laser light emitting element mounted thereon, the light source device comprising: XY on the back
The laser holder plate is moved in the direction and fixed by screw fastening, while a restricting projection is projected rearward on the back surface of the block body in a direction orthogonal to the XY directions .
The laser holder plate has a restriction side which faces at a proper clearance with respect to the outer peripheral side surface of the restricting projection, and 該Re
By making it open on the side edge of the laser holder plate,
The light source device is characterized in that a penetration regulating groove is formed so that the gap can be visually recognized from the outside on the side surface side of the block body . 2. The back of the block body,
While the first regulating protrusion is provided on the side edge along the X direction,
The second regulating projection is provided on the side edge of the back surface along the Y direction,
The laser holder plate includes the first regulation projection and the second regulation.
The first penetration regulating groove and the first
The light source device according to claim 1 , wherein a two-penetration restriction groove is formed .