JPH0667313A - Variable power optical device - Google Patents

Abstract

PURPOSE:To provide the optical variable power device which is simple in constitution and is set largely with a variable power rate without deteriorating lens performance. CONSTITUTION:This variable power optical device has a lens imposing base 40 movable between first and second positions where the optical axes of a first lens group of a first magnification and a second lens group of a second magnification are aligned respectively to prescribed optical axes, a second stationary reflection mirror 34 which reflects incident light along the prescribed optical axis, a second moving reflection mirror 36 movable between a retreat position where the reflection of the incident light by the reflection mirror is permitted and a reflection position where the incident light is reflected so as to advance along the prescribed optical axis before the reflection by the stationary reflection mirror 34 and a variable power changeover mechanism 30 which moves the lens imposing stage 40 to the first position and moves the moving reflection mirror 36 to the retreat position when the first magnification is set and moves the lens imposing base 40 to the second position and moves the moving reflection mirror 36 to the reflection position when the second magnification is set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable power optical apparatus capable of switching the variable power of an optical system by at least a first and a second variable power.

[0002]

2. Description of the Related Art Conventionally, in the case of using one fixed-focus lens as an optical variable magnification, a method of changing the optical path length and further moving the lens, and a zoom lens are used. A method of changing the focal length is known and widely used.

[0003]

However, in the conventional optical variable magnification method, when a fixed focus lens is used, the variable magnification cannot be set to a large value, and a mechanism for changing the optical path length or It has been pointed out that the mechanism for moving the lens becomes complicated. On the other hand, in the case of using a zoom lens, it has been pointed out that when the zoom ratio is set to a large value, the deterioration of the lens performance becomes remarkable. In any case, setting a large scaling factor causes various problems, and improvement is desired.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an optical variable magnification device having a simple structure and capable of setting a large variable magnification ratio without deteriorating lens performance. It is to provide.

[0005]

In order to solve the above-mentioned problems and achieve the object, an optical variable power device according to the present invention has a first lens group having a first magnification and a second magnification. The second lens group that it has, the first and second lens groups are both mounted, and the first position where the optical axis of the first lens group is aligned with a predetermined optical axis, and the second lens group A lens mounting table that is movable between an optical axis and a second position where the optical axis is aligned with the predetermined optical axis; and a fixed reflection mirror that reflects incident light so as to travel along the predetermined optical axis. A retracted position that is located outside the predetermined optical axis and that allows the incident light to be reflected by the fixed reflection mirror, and is provided in the predetermined optical axis so that the incident light is the fixed reflection mirror. It is possible to move between the reflection position where the light is reflected so as to advance along the predetermined optical axis before being reflected by When the reflecting mirror and the first magnification are set, the lens mount is moved to the first position, the movable reflecting mirror is moved to the retracted position, and the second magnification is set. And a variable magnification switching means for moving the lens mount to the second position and moving the movable reflecting mirror to the reflecting position.

[0006]

The following is a description of the case where the configuration of an embodiment of the variable power optical apparatus according to the present invention is applied to an electronic copying apparatus.
It will be described in detail with reference to the accompanying drawings. As shown in FIGS. 1 to 3, the electronic copying apparatus 10 includes an apparatus main body (not shown), a platen glass 12 movably mounted on an upper surface of the apparatus main body, and an original (not shown) placed on the upper surface.
(Shown in FIGS. 2 and 3) and the platen glass 12
The image reading device 14 attached to the apparatus main body in a state of being positioned below the image reading device and the image of the original document on a sheet (not shown) using, for example, an electrophotographic process based on the image information read by the image reading device 14. And an image forming apparatus (not shown) for forming a copy image of the above. Here, the electronic copying apparatus 10 is equipped with a scanning mechanism (not shown) for scanning and reading the image of the original document placed on the platen glass 12. This scanning mechanism includes a document reading device 14 and a platen glass 12
Is configured to generate relative movement between the platen glass 12 and the original reading device 14 and the platen glass 12 is moved in this embodiment. Needless to say, the document reading device 14 may be fixed and moved.

The image reading device 14 includes a variable power optical device 16, which is a feature of the present invention.
Through 3 are configured as shown in FIG. That is, the image reading device 14 includes a housing 18 fixed to a device body (not shown) of the electronic copying device 10 (not shown),
As shown in FIG. 2, an opening 20 is formed on the upper surface of the housing 18 to allow reflected light (scanning light) from a document described later to be introduced therein. The housing 18 also includes a pair of lamps 22 for illuminating the image reading surface of the document placed on the platen glass 12.
a and 22b are attached and attached. On the other hand, in the housing 18, the reflected light (scanning light) from the document is
A line sensor 24 formed of, for example, a CCD for receiving the image information of one line of the original document is provided. The line sensor 24 is connected to an image processing device (not shown), and generates image information for one page from the read image information for each line through a predetermined image processing process.

In this embodiment, the variable power optical device 16 is arranged to guide the reflected light (scanning light) from the document to the line sensor 24 in a variable power state. There is. More specifically, this variable power optical device 16 is shown in FIG.
As shown in (1), the first and second fixed focus lens groups 26 and 28 having different magnifications are provided. These first
And the second fixed focus lens groups 26 and 28 respectively have optical axes L1 and L2 via a magnification switching mechanism 30 described later.
Is set so that the incident light axis L0 of the reflected light (scanning light) to the line sensor 24 can be selectively aligned. In the embodiment, the first magnification set by the first fixed focus lens group 26 is 0.128 times, and the second magnification is the second magnification.
The second magnification set by the fixed-focus lens group 28 is set to 0.256 times. That is, the scaling ratio in this embodiment is 2 (= 0.256 / 0.
128).

As shown in FIG. 2, the variable power optical device 16 is disposed on the bottom surface substantially below the image reading position of the document, receives the reflected light (scanning light) from the document, and receives the line sensor 24. The first for reflecting toward the side opposite to the installation position of
Fixed reflection mirror 32 and this first fixed reflection mirror 3
As shown in FIG. 1, the optical axis L1 of the first fixed focus lens group 26 is aligned with the incident optical axis L0 in order to select the first magnification by the magnification switching mechanism 30 in response to the reflected light from 2. Second fixed reflecting mirror 34 for reflecting this toward the selected first fixed focus lens group 26,
In order to select the second magnification by the magnification switching mechanism 30, when the optical axis L2 of the second fixed focus lens group 28 is aligned with the incident optical axis L0, as shown in FIG. And a second movable reflecting mirror 36 for reflecting toward the selected second fixed focus lens group 28.

Here, the second movable reflecting mirror 36
2 is an upper position that allows the reflected light from the first fixed reflection mirror 32 to enter the second fixed reflection mirror 34 by retracting upward from the incident optical axis L0, as shown in FIG. As shown in FIG. 5, it is rotatably movable between a position below the incident light axis L0 and a position below which the reflected light from the first fixed reflection mirror 32 is allowed to enter. It is pivotally supported. It should be noted that the second movable reflecting mirror 36 is rotationally driven by a later-described rotating mechanism 38 which is driven in synchronization with the magnification switching mechanism 30.

That is, when the optical axis L1 of the first fixed focus lens group 26 is aligned with the incident optical axis L0 by the magnification switching mechanism 30, the rotation mechanism 38 interlocking with the magnification switching mechanism 30 causes The second movable reflecting mirror 36 is rotated to the upper position, and the reflected light from the first fixed reflecting mirror 32 is allowed to enter the second fixed reflecting mirror 34. As a result, the reflected light from the first fixed reflection mirror 32 is reflected by the second fixed reflection mirror 34 and is magnified via the first fixed focus lens group 26, and then is reflected by the line sensor 24. It will be received.
On the other hand, when the optical axis L2 of the second fixed focus lens group 28 is aligned with the incident optical axis L0 by the magnification switching mechanism 30, the rotation mechanism 38 interlocked with the magnification switching mechanism 30 causes The movable reflecting mirror 36 is rotated to the lower position and placed in front of the second fixed reflecting mirror 36. As a result, the reflected light from the first fixed reflecting mirror 32 is reflected by the second movable reflecting mirror 36 and
The light is received by the line sensor 24 in the state of being magnified through the fixed-focus lens group 28.

Next, the above-described magnification switching mechanism 30 will be described with reference to FIGS. The magnification switching mechanism 30 includes a lens mounting table 40 on which the first and second fixed focus lens groups 26 and 28 described above are mounted. The lens mount 40 includes a first position (position shown in FIGS. 1 to 3) for aligning the optical axis L1 of the first fixed focus lens group 26 with the incident optical axis L0, and a second fixed focus lens group. 28 for aligning the optical axis L2 of 28 with the incident optical axis L0
Between the positions (the positions shown in FIGS. 4, 5 and 10)
It can be moved back and forth. Specifically, a slide guide 41 is integrally attached to the lower surface of one side of the lens mounting table 40 on the line sensor 24 side. A guide shaft 42 extending along a horizontal direction in the drawing, which is orthogonal to the incident optical axis L0, relatively slidably penetrates through the sliding guide 41. In addition, the second of the lens mounting table 40
On the other side of the fixed reflection mirror 34 side, a guide rail 44 extending parallel to the guide shaft 42 is provided.

Here, both the guide shaft 42 and the guide rail 44 are fixed on the bottom surface of the housing 18. On the other hand, a roller 46 rolling on the upper surface of the guide rail 44 is provided on the other side edge portion of the lens mounting table 40.
It is attached rotatably around a rotation axis parallel to the incident optical axis L0. In this way, the lens mounting table 40 is movably supported along the horizontal direction orthogonal to the incident optical axis L0.

The magnification switching mechanism 30 also includes a drive mechanism 48 for reciprocating the lens mounting table 40. The drive mechanism 48 includes a reversible drive motor 50 having a motor shaft 50a that is rotated around a vertical axis in the figure, and a reduction transmission mechanism 54 that reduces the rotation of the motor shaft 50a and transmits the rotation to the output gear 52. Is equipped with. In this embodiment, the reduction transmission mechanism 54 includes a small-diameter drive gear 54a coaxially fixed to the motor shaft 50a.
A large-diameter first intermediate gear 5 meshing with the drive gear 54a
4b and a second intermediate gear 54c coaxial with the first intermediate gear 54b and having a slightly smaller diameter than the first intermediate gear 54b, and the output gear 52 meshes with the second intermediate gear 54c. This output gear 52 has an output pulley 5 coaxially therewith.
6 is fixed, and on the outer periphery of the output pulley 56,
A wire 58 as a driving force transmission medium described later is wound.

Here, at the above-mentioned first position, the pair of first projections 60a, 60b integrally formed on the right end surface of the lens mounting table 40 in the drawing is a view of the guide shaft 42 and the guide rail 44. The position is set so as to be accurately regulated by abutting on the pair of first position regulation pieces 62a and 62b respectively attached to the right end of the center. Also,
The above-mentioned second position is the pair of second protrusions 64a, 64 integrally formed on the left end surface of the lens mounting table 40 in the figure.
b is a pair of second position regulating pieces 66 attached to the left ends of the guide shaft 42 and the guide rail 44 in the figure, respectively.
It is set so that the positions are accurately regulated by abutting on a and 66b, respectively.

As shown in FIG. 3, one end of the wire 58 is attached to a mounting piece 68 formed on the lower surface of the lens mounting table 40 so as to integrally project downward, in the moving direction of the lens mounting table 40. It is directly connected to one side of a connecting member 70 (shown in FIG. 6) that is movably attached along the predetermined amount D0. Further, the other end of the wire 58 is connected to the other side of the connecting member 70 via the rotating mechanism 38 described above. More specifically, the pair of mounting rods 72 is provided on the side surface of the mounting piece 68 in a state of standing upright on the side surface of the mounting piece 68 and being separated by a predetermined amount D1 along the moving direction of the lens mounting table 40.
a and 72b (diameter d1) are planted. On the other hand, the connection member 70 is provided with long grooves 74a and 74b into which the mounting rods 72a and 72b are fitted, respectively.
It is formed in a state of extending by a predetermined amount D2 along the movement direction of 0. As is clear from the above description, the predetermined amount D2 has the following relationship. That is, D2 = D0 + d1

Therefore, when the drive motor 50 is started and the motor shaft 50a is rotationally driven in the counterclockwise direction in FIG. 1, the wire 58 is in the state shown in FIG. 6 (that is, the intermediate portions of the long grooves 74a and 74b). Mounting rod corresponding to
2a and 72b are respectively located), and the connecting member 70 connected to the pulling member is moved to the right in the drawing. Here, as the connecting member 70 moves to the right in the drawing, as shown in FIG.
Until the left end of 4b comes into contact with the corresponding mounting rods 72a, 72b, the connecting member 70 only moves, and the mounting piece 68 (and therefore the lens mounting table 40) does not move at all. On the other hand, when the left ends of the long grooves 74a and 74b come into contact with the corresponding mounting rods 72a and 72b, the mounting piece 68 (and hence the lens mounting table 50) will move along with the movement of the wire 58 to the right in the figure. It will move to the right in the figure as a unit.

When the drive motor 50 is started and the motor shaft 50a is driven to rotate in the clockwise direction in FIG. 1, the wire 58 is in the state shown in FIG. 6 (that is, the long groove 7).
Mounting rod 72 corresponding to the intermediate portion of 4a, 74b
a) and 72b are respectively located), the connection member 70 connected to the pulling member is pulled to the left side in the drawing and is moved to the left side in the drawing. Here, as the connecting member 70 moves to the left in the drawing, as shown in FIG. 8, the long grooves 74a, 74 are formed.
Only the connecting member 70 moves until the right end of b comes into contact with the corresponding mounting rods 72a and 72b, and the mounting piece 68 (and hence the lens mounting table 40) does not move at all. On the other hand, when the right ends of the long grooves 74a and 74b come into contact with the corresponding mounting rods 72a and 72b, the mounting piece 68 (and thus the lens mounting table 40) will move along with the movement of the wire 58 to the left in the figure. It will move to the left in the figure as a unit.

On the other hand, as shown in FIG. 3, a detection dog 76 is fixed to the lower surface of the lens mounting table 40 so as to move integrally therewith. A detection sensor 78, which is turned on by the proximity of the detection dog 76, is fixed on the bottom surface of the housing 18. Here, as for the relative disposition position of the detection dog 76 and the detection sensor 78, as shown in FIG. 9, the lens mounting table 40 is at the first position (that is, the pair of first projections 6).
0a and 60b are set to be turned on in a state in which they are close to the first position regulating pieces 62a and 62b from the left side in the figure up to a predetermined distance D3). Here, the predetermined distance D3 is set by the following equation in relation to the movable distance D0 described above. That is, D3≈D0 / 2

The detection sensor 78 is connected to a control unit (not shown), and the control unit detects the rotation amount of the motor shaft 50a in order to detect the current position of the lens mounting table 40. A rotary encoder (not shown) is connected. In this control unit, when the detection sensor 78 is turned on, when the number of pulses is detected by the rotary encoder corresponding to a moving distance of about 1 mm from this turning on time, the current is supplied to the drive motor 50 described above. Interrupt (ie drive motor 5
It is configured so that the driving force to the lens mounting table 40 is canceled and the lens mounting table 40 is movable by releasing the excitation state of 0).

A first forced biasing mechanism 80, which will be described later, is arranged at a position where the detection sensor 78 is turned on by the detection dog 76. Then, by the urging force from the first forced urging mechanism 80, the first protrusions 60a, 60b abut on the first position restricting members 62a, 62b without using the driving force of the drive motor 50, It is designed to be brought to the first position. Here, the detection sensor 78
The size of the detection dog 76 is set so as to maintain the on-operation state after the on-operation until it is brought to the first position.

Further, the first forcibly urging mechanism 80, as shown in FIGS. 3 and 9, has the support shaft 8 on the bottom surface of the housing 18.
The first and first pivotally supported shafts 2 are swingably supported about an axis extending along a horizontal direction orthogonal to the moving direction of the lens mounting table 40 (that is, along the optical axis direction). Pressing member 8
It is equipped with 4. The first pressing member 84 is formed in a substantially L shape in a front view shown in the drawing, and the support shaft 82 is attached to a bent portion thereof. Here, the pressing piece 84a constituting one of the L-shaped parts of the first pressing member 84 is as shown in FIG.
As shown in FIG. 5, the left side surface in the drawing of the protruding piece 86 that is integrally fixed to the lower surface of the lens mounting table 40 and extends downward is directed to the right side in the drawing (that is, at the first position). The pressed piece 84b which is set so as to press and which constitutes the other
As shown in FIG. 9, the right side of the protruding piece 86 in the drawing is pressed toward the right in the drawing (that is, so as to rotate around the support shaft 82 in the clockwise direction). It is set.

The first forced urging mechanism 80 urges the first pressing member 84 to the right in the drawing.
The coil spring 88 is further provided. In detail, one end of the first coil spring 88 is connected to the middle portion of the pressing piece 84a of the first pressing member 84, and the other end is connected to the bottom surface of the housing 18. The extension axis of the first coil spring 88 is the support shaft 8.
By crossing the two rotation axes (that is, every time the neutral position is passed), the rotation biasing direction of the biasing force applied to the first pressing member 84 is set to be reversed.
More specifically, as shown in FIG. 3, when the extension axis of the first coil spring 88 is located above the rotation axis of the support shaft 82, the urging force of the first coil spring 88 causes , The first pressing member 84 is urged to rotate clockwise. On the other hand, as shown in FIG.
The extending axis of the first coil spring 88 is the support shaft 82.
In the state in which the first pressing member 84 is located below the rotation axis of the first pressing member 84,
Will be urged to rotate counterclockwise.

Here, as shown in FIG. 9, the state in which the first pressing member 84 is biased counterclockwise by the biasing force of the first coil spring 88 and is elastically brought to the pressed position. Then, the protruding piece 8 attached to the lower surface of the lens mounting table 40 moved from the second position toward the first position
6 is set so that it can pass above the pressing piece 84a, contact the left side surface of the pressed piece 84b from the left side in the drawing, and press it toward the right side in the drawing. The detection sensor 78 is set to be turned on by the detection dog 76 when the protruding piece 86 contacts the left side surface of the pressed piece 84b.

Further, the lens mounting table 40 further moves to the right in the drawing toward the first position, and the protruding piece 86 pushes the pressed piece 84.
When the left side surface of b is further pressed and moved about 1 mm from the contact position shown in FIG. 9 to the right in the figure, the first
When the pressing member 84 of is rotated clockwise,
The extension axis of the first coil spring 88 crosses upward the rotation axis of the support shaft 82. As a result,
The rotation direction of the first pressing member 84 due to the urging force of the first coil spring 88 is reversed, and this time, it is rotated clockwise in the drawing. Therefore, the urging force of the first coil spring 88 urges the first pressing member 84 to rotate from the pressed position shown in FIG. 9 toward the pressing position shown in FIG.

As the first pressing member 84 is rotationally biased to the pressing position, the pressing piece 84a of the first pressing member 84 is now left of the protruding piece 86, as shown in FIG. The surface is pressed to move and bias it to the right in the figure. On the other hand, as described above, with the movement of the lens mounting table 40 to the right by about 1 mm, the excitation state of the drive motor 50 is cut off, and the lens mounting table 40 is brought into a movable state. In this way, the first protrusions 60a and 60b of the lens mounting table 40 are moved by the biasing force of the first coil spring 88 to the first position regulating members 62a and 62b.
Each of them comes into elastic contact with b, in other words, the lens mounting table 40 is elastically regulated (held) at the first position by the urging force of the first coil spring 88.

That is, in this embodiment, the position of the lens mount 40 is restricted to the first position by the drive motor 50.
Is not achieved by abutting the first protrusions 60a, 60b with the first position regulating members 62a, 62b by the driving force of the first position regulation member 60a, 60b, respectively. Immediately before contacting the members 62a and 62b respectively, the driving force of the drive motor 50 is extinguished, and the lens mounting table 4
In a state where 0 is movable, the first protrusions 60a and 60b are moved to the first position by the urging force of the first coil spring 88.
This is achieved by elastically abutting the position restricting members 62a and 62b respectively. As a result, when the lens mount 40 is held at the first position, an unnecessary load does not act on the drive motor 50, energy saving is achieved, and the life of the drive motor 50 can be extended. Will be able to play.

On the other hand, when the switching signal from the first position to the second position of the lens mounting table 40 is input thereto, the control unit described above drives the driving motor 50 in the reverse direction to drive the lens mounting table 40. 1 from the first position shown in FIG.
The movement drive is started toward the second position indicated by 0. Along with the movement of the lens mount 40 to the left in the figure, the protruding piece 8
6 moves the right side surface of the pressing piece 84a of the first pressing member 84 toward the left side in the drawing, and as a result, the first pressing member 84 resists the biasing force of the first coil spring 88. It is urged to rotate in the counterclockwise direction. As the first pressing member 84 rotates counterclockwise, the first pressing member 84
The extension axis of the coil spring 88 of the first support shaft 82
When the first pressing member 84 is traversed downwards, the direction of rotation of the first pressing member 84 is reversed by the first coil spring 88, and this time, the first pressing member 84 moves counterclockwise. It is urged to rotate around the direction, and the state shown in FIG. 9 is passed.

Further, when the state shown in FIG. 9 is passed, the detection dog 76 separates from the detection switch 78 to the left in the figure and is turned off. Here, the control unit is configured to reset the detection state of the current position of the lens mounting table 40 in the rotary encoder when the detection switch 78 is turned off.
That is, the position where the detection switch 78 is turned off is defined as the origin position of the lens mounting table 40. On the other hand, the lens mounting table 40 heading to the second position is displaced just before the second position shown in FIG. 10, specifically, from the second position toward the right side in the drawing by the above-mentioned predetermined distance D3. In order to accurately regulate the position to the position shown in FIG. 11, it is set to detect from the above-mentioned origin position based on the number of detection pulses by the above-mentioned rotary encoder. In this way, the origin position is reset each time the lens mounting table 40 is moved from the first position to the second position, and the origin position shown in FIG. 11 is set immediately before the second position. The indicated position is defined extremely accurately in a state where the detection error is always eliminated and the detection error is never accumulated.

Here, the above-mentioned control unit is shown in FIG.
As shown in, the front side of the second position (close to the first position)
When it is detected that the lens mounting table 40 is displaced to the position deviated by the predetermined distance D3 on the basis of the detection of the number of pulses by the rotary encoder, the lens mounting table 40 comes into contact with the second position described later. The forced urging mechanism 90 is provided. Further, when it is detected that the position is moved by about 1 mm from the position shown in FIG. 11 toward the second position, the control unit interrupts the supply of the current to the drive motor 50 described above, and the lens mounting table. The driving force applied to the lens mounting table 40 is eliminated, and the lens mounting table 40 is movable. As a result, the lens mount 40 moves from the position shown in FIG. 11 toward the second position by about 1 mm, and the driving force of the drive motor 50 is generated by the biasing force from the second forced biasing mechanism 90. The second protrusions 64a and 64b without using
Contact the second position regulating members 66a and 66b,
It is designed to be brought to the second position as shown in.

The second forcibly urging mechanism 90 has basically the same structure as the first forcibly urging mechanism 80 described above, but as shown in FIGS. A second pressing member 94 is pivotally supported on the bottom surface via a support shaft 92 so as to be swingable around an axis extending along a horizontal direction orthogonal to the moving direction of the lens mounting table 40. .
The second pressing member 94 is formed in a substantially L shape in a front view shown in the drawing, and the support shaft 92 is attached to the bent portion thereof. Here, as shown in FIG. 11, the pressing piece 94a that constitutes one of the L-shaped ones of the second pressing members 94 has the right side surface of the above-mentioned protruding piece 86 facing the left side in the drawing ( That is, it is set so as to press (toward the second position), and the pressed piece 94b forming the other side is the protruding piece 86b.
Is pushed toward the left side in the figure by the left side surface in the figure, and the support shaft 9
It is set to rotate in two counterclockwise directions.

Further, the second forced urging mechanism 90 urges the second pressing member 94 to the left in the drawing.
The coil spring 96 is further provided. In detail, one end of the second coil spring 96 is connected to the middle portion of the pressing piece 94 a of the second pressing member 94, and the other end is connected to the bottom surface of the housing 18. The extension axis of the second coil spring 96 is the support shaft 9
By crossing the two rotation axes (that is, every time the neutral position is passed), the rotation urging direction by the urging force acting on the second pressing member 94 is set to be reversed.
More specifically, as shown in FIG. 10, when the extension axis of the second coil spring 96 is located above the rotation axis of the support shaft 92, the urging force of the second coil spring 96 causes The second pressing member 94 is biased so as to rotate counterclockwise. On the other hand, as shown in FIG. 11, when the extension axis of the second coil spring 96 is located below the rotation axis of the support shaft 92,
By the urging force of the coil spring 96, the second pressing member 94 is urged to rotate in the clockwise direction.

Here, in a state where the second pressing member 94 is urged clockwise by the urging force of the second coil spring 96 to be elastically brought to the pressed position, the first pressing member 94 moves from the first position to the first position. The lens mount 4 which has been moved to the position 2
The protruding piece 86 attached to the lower surface of the 0 is a pressing piece 94a.
When it passes through above and is brought to the position shown in FIG. 11, it comes into contact with the right side surface of the pressed piece 94b from the right side in the figure and can press it toward the left side in the figure. Is set to. Further, as is apparent from the above description, after the protruding piece 86 contacts the right side surface of the pressed piece 94b, the lens mounting table 40 is further moved toward the second position by about 1 mm.
Only to the left in the drawing, and the protruding piece 86 further presses the right side surface of the pressed piece 94b, so that the second pressing member 94
Rotates in the counterclockwise direction, so that the extension axis of the second coil spring 96 crosses the above-described rotation axis of the support shaft 92 upward.

As a result, the direction of rotation of the second pressing member 94 due to the urging force of the second coil spring 96 is reversed,
This time, it is urged to rotate counterclockwise in the figure. Therefore, the urging force of the second coil spring 96 causes the second pressing member 94 to move from the pressed position shown in FIG.
It is urged to rotate toward the pressing position indicated by 0. Then, as the second pressing member 94 is rotationally biased to the pressing position, as shown in FIG.
The pressing piece 94a of this time presses the right side surface of the protruding piece 86, and urges it to move leftward in the drawing. On the other hand, as described above, with the further movement of the lens mounting table 40 to the left by about 1 mm from the position shown in FIG. 11, the excitation state of the drive motor 50 is cut off, and the lens mounting table 40 is movable. It will be brought to a different state. In this way, the second protrusions 64a and 64b of the lens mounting table 40 elastically contact the second position regulating members 66a and 66b by the urging force of the second coil spring 96, respectively.
In other words, the lens mounting table 40 is placed in the second position at the second position.
The urging force of the coil spring 96 elastically regulates (holds) the position.

That is, in this embodiment, the position of the lens mount 40 to the second position is regulated by the drive motor 50.
Drive force of the second projections 64a, 64b to contact the second position restricting members 66a, 66b, respectively, rather than the second projections 64a, 64b to the second position restricting members 66a, 66b. The second coil spring 96 is provided in a state in which the driving force of the drive motor 50 is extinguished immediately before the contact with 66 b, respectively, and the lens mount 40 is movable.
The second protrusions 64a and 64b are elastically brought into contact with the second position restricting members 66a and 66b, respectively, by the biasing force of. As a result, when the lens mounting table 40 is held at the second position, the drive motor 5
No unnecessary load acts on 0, energy saving is achieved, and the life of the drive motor 50 can be extended.

On the other hand, when the switching signal from the second position to the first position of the lens mounting table 40 is input thereto, the control unit described above further drives the drive motor 50 in the reverse direction (that is, in the normal direction). ), And starts the movement drive of the lens mounting table 40 from the second position shown in FIG. 10 toward the first position. With the movement of the lens mounting table 40 to the right in the drawing, the protruding piece 86 moves the left side surface of the pressing piece 94a of the second pressing member 94 toward the right in the drawing, and as a result, the second The pressing member 94 is driven to rotate clockwise in the figure against the biasing force of the second coil spring 96. At the time when the extension axis of the second coil spring 96 crosses the rotation axis of the second support shaft 92 downward with the clockwise rotation of the second pressing member 94. , The second pressing member 9 by the second coil spring 96
11, the second pressing member 94 is rotationally biased in the clockwise direction, as shown in FIG.
It will pass the state shown in.

In this way, the lens mount 40 is shown in FIG.
The second position shown in FIG. 11 passes through the position shown in FIG. 11 and is moved toward the first position. Then, as described above, it passes through the position shown in FIG. 9 and is brought to the first position shown in FIG.

Next, referring to FIG. 12 and FIGS. 6 to 8 described above, the drive mechanism 48 in the magnification switching mechanism 30.
The driving mode of is described in detail. First, the lens mount 40
Is in the first position, that is, in the state where the magnification by the first fixed focus lens group 26 is set, as will be described later, the pair of mounting rods 72a, 72a,
2b are corresponding long grooves 74a, 74b as shown in FIG.
It is located in the approximate center of each. From the state shown in FIG. 6, when the drive motor 50 reversely drives the motor shaft 50a under the control of the control unit to start moving the wire 58 to the left in the figure via the deceleration transmission mechanism 54, In the initial stage indicated by reference numeral T1, the relative movement of the mounting rods 72a and 72b within the pair of long grooves 74a and 74b formed in the connecting member 70 to which the wire 58 is connected is allowed, and the connecting member 70 is drawn. The lens mounting table 40 itself remains at the first position only by moving toward the center right side.

Then, as shown in FIG. 8, both long grooves 74a,
Mounting rods 72a, 72b corresponding to the right end of 74b
Then, the lens mounting table 40 is moved toward the second position in accordance with the pulling of the wire 58 to the left in the figure for a period T2 until it is brought to the position shown in FIG. It will be moved. Then, by passing through the position shown in FIG. 9, the detection information of the current position of the lens mounting table 40 in the control unit is reset, and the origin search is executed.

On the other hand, the lens mount 4 is placed at the position shown in FIG.
When 0 is brought, at this point, the projection piece 86 attached to the lens mounting table 40 comes into contact with the pressed piece 94b of the second pressing member 94 of the second forcibly urging mechanism 90,
Thereafter, while moving about 1 mm toward the position shown in FIG. 10, the second pressing member 94 is rotated counterclockwise, and by the biasing force of the second coil spring 96,
The lens mounting table 40 is urged to move toward the second position and the driving motor 50 is demagnetized to eliminate the driving force of the driving motor 50. In this way, about 1 mm from the position shown in Fig. 11.
After that, until the second position shown in FIG. 10,
As indicated by the period indicated by reference numeral T3, the second forced biasing mechanism 9
The urging force from 0 will move it toward the second position.

Here, during this period T3, the driving of the drive motor 50 is stopped, so that the pulling force of the wire 58 to the left in the figure disappears, but the lens mount 40 moves. Since the second forcibly biasing mechanism 90 directly moves and biases it toward the second position, the mounting rods 72a, 72b move leftward in the drawings in the corresponding long grooves 74a, 74b. As a result, as shown in FIG. 8, from the state in which the mounting rods 72a, 72b are located at the right ends of the corresponding long grooves 74a, 74b to the state in which they are located substantially in the center of each, as shown in FIG. Return to. On the other hand, after the lens mounting table 40 is brought to the second position shown in FIG. 10, the lens mounting table 40 is elastically held at the second position by the urging force from the second forced urging mechanism 90. Will be That is, the magnification by the second fixed focus lens group 28 is set.

Further, from the state where the lens mounting table 40 is brought to the second position shown in FIG. 10, the drive motor 50 drives the motor shaft 50a in the forward direction under the control of the control unit to transmit the deceleration. When the wire 58 starts to move to the right in the drawing via the mechanism 54, as shown in FIG. 8, in the initial stage of the returning operation indicated by the reference numeral T4, the wire 58 is formed on the connecting member 70 to which the wire 58 is connected. The relative movement of the mounting rods 72a and 72b within the pair of long grooves 74a and 74b is allowed, and the connecting member 70 only moves to the right in the drawing, and the lens mounting table 40 itself moves to the second position. Will stay in. Then, as shown in FIG. 7, both long grooves 74a, 74
When the left ends of b contact the corresponding mounting rods 72a and 72b respectively, thereafter, the lens 58 is pulled according to the pulling of the wire 58 to the right in the figure for a period T5 until it is brought to the position shown in FIG. The mounting table 40 is moved toward the first position.

On the other hand, the lens mount 40 is placed at the position shown in FIG.
Then, at this point, the first forced biasing mechanism 8
While the protruding piece 86 attached to the lens mounting table 40 abuts the pressed piece 84b of the first pressing member 84 of 0, and moves about 1 mm toward the first position shown in FIG.
The first pressing member 84 is rotated clockwise so that the lens mounting table 40 is moved and urged toward the first position by the urging force of the first coil spring 96, and the drive motor 50 is demagnetized. Then, the driving force of this is extinguished.
In this way, after the position shown in FIG.
As indicated by the period indicated by 6, the urging force from the first forced urging mechanism 80 causes the urging force to move toward the first position.

Here, during this period T6, the driving of the drive motor 50 is stopped, so the pulling force of the wire 58 to the right in the figure disappears, but the lens mounting table 40 Since the first forcible biasing mechanism 80 directly moves and biases it toward the first position, the mounting rods 72a, 72b move in the corresponding long grooves 74a, 74b rightward in the drawing. As a result, as shown in FIG. 7, from the state where the mounting rods 72a and 72b are located at the left ends of the corresponding long grooves 74a and 74b, to the state where they are located at the substantially central portions of the respective long grooves 74a and 74b, as shown in FIG. Return to. On the other hand, after the lens mounting table 40 is brought to the first position shown in FIG. 3, it is elastically held again at the first position by the biasing force from the first forced biasing mechanism 80. Will be done. That is, the magnification by the first fixed focus lens group 26 is set again.

As described above, in this embodiment, as described above, the positioning operation of the lens mounting table 40 to the first position is performed by the first position regulating piece corresponding to the first projections 60a and 60b. 62a and 62b respectively have a first forced urging mechanism 80.
The second position regulating pieces 66a, 6b corresponding to the second protrusions 64a, 64b can achieve the positioning operation of the lens mounting table 40 to the second position.
The driving force of the drive motor 50 is not used so as to be achieved by being urged by the second forcibly urging mechanism 90 to 6b, respectively.
Distance D3 which is the last approach distance to the position
In order to allow the first and second forced biasing mechanisms 80 and 90 to move and bias each, a connecting member 70 that is connected to the wire 58 and is moved and driven by the predetermined distance D3. , A pair of mounting rods 72a, 7b between the mounting piece 68 mounted on the lens mounting table 40.
2b and the corresponding long grooves 74a and 74b are engaged with each other so as to be relatively movable.

In this embodiment, the positioning operation of the lens mounting table 40 to the first position is performed by the first position regulating pieces 62a, 6 corresponding to the first protrusions 60a, 60b.
2b is achieved by being urged by the first forced urging mechanism 80, respectively, and the positioning operation of the lens mounting table 40 to the second position is performed by the second protrusions 64a, 64b corresponding to the second operation. This is achieved by urging the position regulating pieces 66a and 66b by the second forced urging mechanism 90, respectively, so that the first and second positions are set to the first and second positions even when the power is off. Via the forced urging mechanisms 80 and 90,
It will be held elastically. In this way, even when the printer is moved when the power is turned off, the lens mounting table 40 does not rattle and is stably held in the first or second position.

Next, the above-mentioned second movable reflection mirror 36.
FIG. 13 to FIG. 18 and FIG. 1 described above for the configuration of the rotating mechanism 38 for rotationally driving between the upper position and the lower position according to the magnification switching operation of the magnification switching mechanism 30. Will be described in detail.

First, as shown in FIG. 1, the wire 58 as a driving force transmission medium for transmitting the driving force of the drive motor 50 has one end connected to the right end in the drawing of the connecting member 70, and once, as shown in FIG. After being extended rightward in the drawing along the moving direction of the lens mounting table 40, it is wound around the output pulley 56 and extended leftward in the drawing along the moving direction of the lens mounting table 40. After that, it is wound around the first idle pulley 98, and its extending direction is changed so as to be directed rearward along the optical axis direction, and then it is wound around the driven pulley 100 that constitutes the rotating mechanism 38. It is rotated so that its extension direction is changed so as to be directed forward along the optical axis direction, and finally, it is wound around the second idle pulley 102, and the extension direction is changed to the moving direction of the lens mounting table 40. Of the above-mentioned connecting member 70 after being changed so that It is routed as to be connected to the left end.

Here, the above-mentioned first and second idle pulleys 98 and 102 are arranged on the bottom surface in the housing 18, while the driven pulley 100 is on the outer surface of the housing 18 of the lens mounting table 40. It is attached rotatably around a rotation axis set parallel to the moving direction. Therefore, the portion of the wire 58 passed between the driven pulley 100 and the first and second idle pulleys 98, 102 is
Through an opening (not shown) formed in the housing 18,
It is set so as to extend inside and outside the housing 18. That is, through the wire 58, the magnification switching mechanism 3
The drive mechanism 48 and the rotating mechanism 38 of 0 are connected to each other, and the rotating mechanism 38 moves the second movable reflecting mirror 3 in accordance with the driving drive of the lens mounting table 40 by the drive mechanism 48.
6 can be driven to rotate.

The structure of the rotating mechanism 38 will be described below. As shown in FIG. 13, the rotating mechanism 38 includes a driven pulley 100 rotatably attached to the outer surface of the housing 18 and the driven pulley 1 as described above.
00, the intermittent gear 104 integrally formed coaxially therewith, and the partial gear teeth 104a of the intermittent gear 104.
A driven gear 106, which is provided so as to be meshed with the rotary gear, and a rotary support shaft 108 for rotatably supporting the driven gear 106 around the rotation axis parallel to the rotation axis of the intermittent gear 104 on the outer surface of the housing 18. , The pin 11 mounted on the outer surface of the driven gear 106 at a position offset from the center of rotation
0, one end is connected to the pin 110, the other end is attached to the outer surface of the housing 18, and the driven gear 106
And a third coil spring 112 for biasing the rotation of the. The rotary support shaft 108 that supports the driven gear 106 is introduced into the housing 18 through the outer side wall of the housing 18, and the second movable reflection mirror 36 described above is integrally connected (that is, Fixation)
Has been done.

Here, the third coil spring 11
2 indicates that the rotational urging direction due to the urging force acting on the driven gear 106 is caused by the extension axis of the pedestal traversing the rotation axis of the rotation support shaft 108 (that is, each time the neutral position is passed). It is set to reverse. More specifically, FIG.
As shown in FIG. 7, when the extension axis of the third coil spring 112 is located above the rotation axis of the rotation support shaft 108, the driven gear 106 is counteracted by the urging force of the third coil spring 112. It will be urged to rotate clockwise. On the other hand, as shown in FIG.
The extension axis of the coil spring 112 of the rotary support shaft 108 is
When the third coil spring 112 is located below the rotation axis of the third coil spring 112 as shown in FIG.
The driven gear 106 is biased to rotate clockwise by the biasing force.

The upper biasing position of the driven gear 106 biased by the third coil spring 112 is such that the second movable reflecting mirror 36 integrally connected to the driven gear 106 has the upper position stopper 114. The upper position of the second movable reflecting mirror 36 is automatically set by defining the upper position by abutting against the lower position stopper 116 (shown in FIG. 5). ), The lower position is defined by abutting against), and is automatically set.

On the other hand, in the partial gear teeth 104a of the intermittent gear 104 described above, the lens mount 40 is positioned at the first position in the magnification switching mechanism 30 via the wire 58 described above, and the first fixed focus lens group is formed. 1st by 26
14, the engagement with the driven gear 106 is released, and the lens mounting table 40 is set so as to be brought to a position displaced further upward. 1 is positioned at the second position, and the second magnification by the second fixed focus lens group 28 is set,
6, the engagement with the driven gear 106 is released,
It is set so as to be brought to a position further deviated downward. Then, the partial gear teeth 104a are moved while the lens mounting table 40 is being moved from the first position to the second position in the magnification switching mechanism 30, or from the second position to the first position. On the way, as shown in FIG. 15, the driven gear 106 meshes with the driven gear 106, so that the extension axis of the third coil spring 112 can be brought to the opposite side beyond the rotation axis of the rotation support shaft 108. It is formed so as to have a range along the circumferential direction.

In this way, in the rotation mechanism 38, the magnification changeover mechanism 30 changes from the first magnification to the second magnification.
The lens mount 40 is the first so that the magnification can be switched to
14 is moved from the upper position to the second position, the intermittent gear 104 is rotationally driven in the counterclockwise direction in the drawing from the upper eccentric position shown in FIG. 14, and passes through the position shown in FIG. It is brought to the downward deflection position shown in FIG. Here, FIG.
When passing through the position shown in FIG. 5, the partial gear teeth 104a of the intermittent gear 104 mesh with the driven gear 106, and
The coil spring 112 is rotationally driven in the clockwise direction against the biasing force of the coil spring 112. As a result, with the rotation of the driven gear 106, the extension axis of the third coil spring 112 is
It is brought downward beyond the rotation axis of the rotary support shaft 108. In this way, the intermittent gear 104 further rotates in the counterclockwise direction, and the partial gear teeth 104a of the intermittent gear 104 move.
Even if it disengages with 6, the rotational biasing direction of the third coil spring 112 is now reversed, so that the biasing force of the third coil spring 112 is rotated in the clockwise direction toward the downward biased position. Will be done.

On the other hand, in the rotating mechanism 38, the lens mount 40 is moved from the second position to the first position so that the magnification switching mechanism 30 can switch from the second magnification to the first magnification. Accordingly, the intermittent gear 104 is rotationally driven in the clockwise direction in the drawing from the lower eccentric position shown in FIG. 16, and is brought to the upper eccentric position shown in FIG. 14 through the position shown in FIG. . Here, when passing through the position shown in FIG. 15, the partial gear teeth 10 of the intermittent gear 104
Reference numeral 4a meshes with the driven gear 106, and rotates this counterclockwise against the urging force of the third coil spring 112. As a result, as the driven gear 106 rotates,
The extension axis of the third coil spring 112 is provided above the rotation axis of the rotation support shaft 108. In this way, the intermittent gear 104 further rotates clockwise,
Even if the partial gear tooth 104a of this gear is disengaged from the driven gear 106, this time, due to the urging force of the third coil spring 112 whose rotational urging direction is reversed, the urging force moves toward the upper eccentric position. It will be pivotally displaced along the counterclockwise direction.

As is apparent from the above description, in the rotating mechanism 38, the driven gear 106 is moved to the upper biasing position or the lower biasing position in order to bring the second movable reflecting mirror 36 to the upper position or the lower position. The final moving operation is elastically pressed to the respective positions by utilizing the biasing force of the third coil spring 112 without utilizing the driving force from the driving mechanism 48 via the wire 58. It is executed by things and each position is elastically held. As a result, in the magnification switching mechanism 30 connected to drive the rotation mechanism 38, the final movement operation of the lens mounting table 40 to the first and second positions is
The first and second coils in the first and second correction biasing mechanisms 80 and 90, respectively, without using the driving force from the driving motor 50, that is, in the state where the driving of the driving motor 50 is canceled. Even if it is configured to be executed by utilizing the biasing force from the springs 88 and 96, in other words, the driven gear 106 is finally moved to the upper biasing position or the lower biasing position via the wire 58. Even if a large driving force is not applied, the driven gear 106 is finally moved to the upper biasing position or the lower biasing position by utilizing the biasing force of the third coil spring 12. .

On the other hand, as is apparent from the above description, the upper urging position or the lower urging position of the driven gear 106, that is, the upper or lower position of the second movable reflecting mirror 36 is the portion of the intermittent gear 104. Since the meshing with the gear tooth 104a is released, the third coil spring 112 is set to be elastically held by the biasing force of the third coil spring 112. In other words, the upper position or the lower position of the second movable reflection mirror 36 is not held in a mechanically fixed state through the meshing of gears or the like. Therefore, if an impact or the like is applied to the electronic copying apparatus 10 during transportation, for example, the second movable reflecting mirror 36 located at the upper position resists the urging force of the third coil spring 112 due to the impact. Then, there is a possibility that a situation may occur in which it is rotated to the lower position. In this way, the lens mounting table 4
0 is held at the first position, and the second movable reflecting mirror 36 is rotated to the lower position even though the first magnification is set, and the first fixed-focus lens from the document is rotated. The optical path length up to the group 26 changes, and the image formation state at the line sensor 24 is defocused. Therefore, in this embodiment, once the second movable reflecting mirror 36 has been rotated to the upper position, the rotation from the upper position to the lower position is prohibited unless the intermittent gear 104 is used. A position holding mechanism 118 is provided for this purpose.

The position holding mechanism 118 will be described in detail below with reference to FIGS. 17 and 18. This position holding mechanism 118, as shown in FIG.
The cam member 120 integrally attached to the inner surface of 6
And is disposed immediately below the second movable reflecting mirror 36 at the upper position while facing the cam member 120, and penetrates the outer wall 18a of the housing 18 described above along the thickness direction. And a locking pin 12 that functions as a cam follower attached movably along the thickness direction.
2 and a leaf spring 126 for urging the locking pin 122 so as to abut the cam surface 124 formed on the inner surface of the cam member 120. Here, the locking pin 122 has a left end (that is, one end) in the drawing protruding outward of the outer wall 18a of the housing 18, and a right end (that is, the other end) of the locking pin 122 in the outer wall 18a in the drawing. The outer wall 18a is penetrated in a state of protruding in one direction.

That is, the locking pin 122 extends into the range of rotation of the second movable reflection mirror 36 where the other end is shown by hatching in FIG. 18, and the second movable reflection at the upper position. By locking the mirror 36, the locking position that prohibits rotation of the mirror 36 to the lower position and the other end are the second position.
The movable reflection mirror 36 is pulled out of the rotation range and is movable between the upper position and the retracted position that allows the second movable reflection mirror 36 to rotate to the lower position.

Specifically, as shown in the expanded state of FIG. 18, one end of the locking pin 122 abuts on the cam surface 124, whereby the locking pin 122 is displaced to the locking position. The second end of the other end is indicated by hatching in the figure
Of the first cam surface portion 124a, which extends into the rotation range of the movable reflecting mirror 36, and the first cam surface portion 124a.
To the outside (that is, cut into the vicinity of the outer surface of the driven gear 106) and one end of the locking pin 122 abuts, whereby the locking pin 122 is displaced to the retracted position and the other end is moved to the second position. And a second cam surface portion 124b that pulls the movable reflecting mirror 36 out of the rotation range. Here, the arrangement positions of the first cam surface portion 124a and the second cam surface portion 124b are, as is clear from FIG. 18, a state in which the driven gear 106 is rotated to the vicinity of the upward biasing position, and , The first cam surface portion 124a faces the locking pin 122 in a state of being rotated to the vicinity of the lower biasing position, and the locking pin is in a state of being rotated between the upper and lower biasing positions. The second cam surface portion 124b is set to face 122.

Since the position holding mechanism 118 is constructed as described above, the cam surface portion 124 of the cam member 120 is in the state where the driven gear 106 is rotated to the upward biasing position as shown in FIG. , The first cam surface portion 124
a is brought to a position facing the locking pin 122 shown by the solid line in FIG. In this way, the locking pin 122 abuts the first cam surface portion 124a and is brought to the locking position. As a result, the second movable reflecting mirror 36 located at the upper position due to the rotation of the driven gear 106 to the upper biasing position is, for example, the driven gear 106 and the intermittent gear 10.
Even if the engagement with the partial gear tooth 104a of No. 4 is released, the locking pin 122 brought to this locking position prohibits the rotation to the lower position, and the satisfactorily holds the upper position. become.

On the other hand, as shown in FIG. 15, when the driven gear 106 is displaced from the upper urging position or the lower urging position, the cam surface portion 124 of the cam member 120 has the second cam surface portion 124b. Is brought to a position facing the locking pin 122 shown by the alternate long and short dash line in FIG. In this way, the locking pin 122 abuts the second cam surface portion 124b and is brought to the retracted position. As a result, with the rotation of the driven gear 106 from the upper urging position to the lower urging position, the second movable reflecting mirror 36 in the upper position is allowed to rotate in the lower position. With the rotation of the driven gear 106 from the lower bias position to the upper bias position, the second movable reflecting mirror 36 in the lower position is allowed to rotate in the upper position.

In this position holding mechanism 118,
In a state where the driven gear 106 is rotated to the downward biasing position as shown in FIG. 16, in the cam surface portion 124 of the cam member 120, the position where the first cam surface portion 124a faces the locking pin 122. Will be brought to. In this way, the locking pin 122 engages the first cam surface portion 12
It comes into contact with 4a and is projected to the locking position. However, the second movable reflecting mirror 36 in the lower position is
Is also urged to its lower position by its own weight, so that, for example, the electronic copying apparatus 10 is impacted and is held in a lower position in a more stable state than in the upper position. It does not cause any problems.

It goes without saying that the present invention is not limited to the configuration of the above-described embodiment and can be variously modified without departing from the gist of the present invention.

For example, in the above-described embodiment, the scaling factor is set to be 2. However, the present invention is not limited to such a configuration, and the scaling factor is set to an arbitrary value. It goes without saying that you can do it.

Further, in the above-mentioned embodiment, the fixed focus fixed focus lens group 2 having two different magnifications is used.
6 and 28 have been described, the present invention is not limited to such a configuration and may be configured to include a fixed focus fixed focus lens group having three or more different magnifications. Needless to say.

Further, in the above-described embodiment, each of the fixed focus lens groups 26 and 28 has been described as having a fixed focus, but it goes without saying that at least one of them may be composed of a zoom lens. .

[0068]

As described above in detail, the optical variable power device according to the present invention has a first fixed focus lens group having a first magnification and a second fixed focus lens group having a second magnification. And the first and second fixed focus lens groups are mounted together,
Between a first position where the optical axis of the first fixed focus lens group is aligned with a predetermined optical axis and a second position where the optical axis of the second fixed focus lens group is aligned with the predetermined optical axis. A movable lens mounting table, a fixed reflection mirror that reflects the incident light so as to travel along the predetermined optical axis, and a fixed reflection mirror that is located outside the predetermined optical axis and in which the incident light is fixedly reflected. A retracted position that allows the light to be reflected by a mirror and a predetermined optical axis are interposed, and the incident light is reflected so as to advance along the predetermined optical axis before being reflected by the fixed reflection mirror. A movable reflecting mirror that is movable between a reflecting position and the lens mount is moved to the first position when the first magnification is set, and the movable reflecting mirror is retracted. Position, and when the second magnification is set,
It is characterized by comprising magnification switching means for moving the lens mount to the second position and moving the movable reflecting mirror to the reflecting position.

Therefore, according to the present invention, it is possible to provide an optical variable power device having a simple structure and capable of setting a large magnification without deteriorating the lens performance.

[Brief description of drawings]

FIG. 1 shows an internal configuration of an electronic copying apparatus to which a configuration of an embodiment of a variable power optical apparatus according to the present invention is applied, in a first variable power state (where a lens mount is brought to a first position). , First
FIG. 3 is a plan sectional view schematically showing an optical axis of the fixed-focus lens group of (1) aligned with an incident optical axis.

FIG. 2 is a side sectional view showing an internal configuration of the electronic copying apparatus shown in FIG.

3 is a front sectional view showing the internal structure of the electronic copying apparatus shown in FIG.

FIG. 4 shows an internal configuration of an electronic copying apparatus to which a configuration of an embodiment of a variable power optical apparatus according to the present invention is applied, in a second variable power state (where a lens mount is brought to a second position). , Second
FIG. 3 is a plan sectional view schematically showing an optical axis of the fixed-focus lens group of (1) aligned with an incident optical axis.

5 is a side sectional view showing an internal configuration of the electronic copying apparatus shown in FIG.

FIG. 6 is a front view showing a connection state between a connection member to which a wire is connected and a mounting piece mounted on the lens mounting table in the variable power switching mechanism.

FIG. 7 is a front view showing the wire pulled from the state shown in FIG. 6 to the right in the figure.

FIG. 8 is a front view showing the wire pulled from the state shown in FIG. 6 to the left in the figure.

FIG. 9 is a front sectional view showing the internal structure of the electronic copying apparatus in a state in which the lens mounting table is brought in immediately before the first position.

FIG. 10 is a front sectional view showing the internal structure of the electronic copying apparatus with the lens mounting table brought to a second position.

FIG. 11 is a front cross-sectional view showing the internal structure of the electronic copying apparatus in a state where the lens mounting table is brought in immediately before the second position.

FIG. 12 is a diagram showing the movement state of the lens mounting table in relation to the driving state of the wire and the operating states of the first and second forced biasing mechanisms.

FIG. 13 is a side view showing the configuration of a rotating mechanism.

FIG. 14 is a side view showing the intermittent gear in an upper eccentric position, that is, a driven gear in an upper urging position.

FIG. 15 is a side view showing a state in which the extension axis of the third coil spring, which meshes with the driven gear and is connected to the driven gear, crosses the rotation axis of the driven gear while the intermittent gear is being rotated. is there.

FIG. 16 is a side view showing the intermittent gear in a downwardly displaced position, that is, in a state in which the driven gear is brought to a downwardly biased position.

FIG. 17 is a front cross-sectional view showing a position holding mechanism provided in a rotating mechanism.

FIG. 18 is a development view showing a cam surface shape of a cam member that constitutes the rotating mechanism.

[Explanation of symbols]

 10 electronic copying device 12 platen glass 14 image reading device 16 optical scaling device 18 housing 18a outer wall 20 opening 22a; 22b lamp 24 line sensor 26 first fixed focus lens group 28 second fixed focus lens group 30 magnification switching mechanism 32 1st fixed reflection mirror 34 2nd fixed reflection mirror 36 2nd movable reflection mirror 38 Rotation mechanism 40 Lens mounting table 42 Guide shaft 44 Guide rail 46 Roller 48 Drive mechanism 50 Drive motor 50a Motor shaft 52 Output gear 54 Reduction transmission mechanism 54a Drive gear 54b First intermediate gear 54c Second intermediate gear 56 Output pulley 58 Wire 60a; 60b First protrusion 62a; 62b First position regulating piece 64a; 64b Second protrusion 66a; 66b 2 position control piece 68 mounting Piece 70 Connection member 72a; 72b Mounting rod 74a; 74b Long groove 76 Detection dog 78 Detection switch 80 First forcing bias mechanism 82 First support shaft 84 First pressing member 84a Pressing piece 84b Pressed piece 86 Protruding piece 88 1st coil spring 90 2nd forced urging mechanism 92 2nd supporting shaft 94 2nd pressing member 94a Pressing piece 94b Pressed piece 96 2nd coil spring 98 1st idle pulley 100 Driven pulley 102 2nd Idle pulley 104 intermittent gear 104a partial gear tooth 106 driven gear 108 rotary support shaft 110 pin 112 third coil spring 114 upper position stopper 116 lower position stopper 118 position holding mechanism 120 cam member 122 locking pin 124 cam surface 124a first Cam surface portion 124b of the second cam Portion 126 is a leaf spring.

Claims (9)

[Claims] 1. A first lens group having a first lens group having a first magnification, a second lens group having a second magnification, and first and second lens groups mounted together. And a second position where the optical axis of the second lens group is aligned with the predetermined optical axis, and a second position where the optical axis of the second lens group is aligned with the predetermined optical axis. A fixed reflection mirror that reflects the incident light so as to travel along the predetermined optical axis; and a fixed reflection mirror that is located outside the predetermined optical axis and that is reflected by the fixed reflection mirror. It is movable between a retracted position and a reflection position which is interposed in the predetermined optical axis and reflects the incident light so as to advance along the predetermined optical axis before being reflected by the fixed reflection mirror. The movable reflecting mirror, and the lens mount is set to the first position when the first magnification is set. The movable reflecting mirror is moved to the retracted position while being moved, and the lens mounting table is moved to the second position when the second magnification is set, and the movable reflecting mirror is moved to the reflecting position. A variable-magnification optical device comprising a variable-magnification switching means for moving the lens to a position. 2. The variable magnification switching means is provided with one drive motor, and the driving force of the drive motor drives and drives the lens mounting table and the movable reflecting mirror. The variable power optical device according to claim 1. 3. The variable power optical device according to claim 1, wherein the movable reflecting mirror is attached so as to be rotatable between the retracted position and the reflecting position. 4. The variable magnification switching means comprises one drive motor, drive means for moving the lens mounting table by the drive force of the drive motor, and the movable reflection by the drive force of the drive motor. 4. The variable power optical device according to claim 3, further comprising: a rotating unit that rotationally drives the mirror. 5. The movable reflection mirror is rotated above the predetermined optical axis at the retracted position, and is rotated below the retracted position at the reflection position. The variable power optical device according to item 3. 6. The variable power optical apparatus according to claim 4, wherein the driving force of the driving motor is transmitted to the driving means and the rotating means via a driving force transmission member. 7. The driving force transmitting member is composed of one wire, and the wire is connected at both ends thereof to the lens mount so as to be displaceable by a predetermined amount along the moving direction thereof. The variable power optical device according to claim 6, wherein the variable power optical device is connected to a member. 8. The variable magnification switching means comprises: a single drive motor; and a drive force of the drive motor between which the lens mount is placed between immediately before the first position and immediately before the second position. Drive means for moving and driving the lens mounting table, control means for canceling the driving force of the drive motor when the lens mounting table is moved immediately before the first or second position, and immediately before the first position. First forcing means for moving and urging the lens mounting table moved to the first position to the first position, and the lens mounting table moved immediately before the second position to the second position. The electrophotographic apparatus according to claim 1, further comprising a second forcibly urging unit that urges the moving member. 9. The electrophotographic apparatus according to claim 8, wherein each of the first and second forcing means includes a coil spring.