JPH09197743A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage to various kinds of devices such as a light deflector, at the time of executing the opening/closing operations of an upper frame and to widely open the upper frame, for facilitating repair of paper jamming and the maintenance. SOLUTION: The upper and lower frames 50 and 52 of the image forming device are separably constituted and the upper frame 50 is pivotally supported by a supporting shaft 58 and turned between a working condition position and an opening position, to enable the opening/closing operations, with respect to the lower frame 52. Devices such as an optical scanner 68 arranged in the upper frame 50 are supported so that the opening/closing operations are executed while the working condition attitudes of the devices are kept, by an attitude holding means. Further, a buffer means not for imparting an impact to the devices such as the optical scanner 68 arranged in the upper frame 50, at the time of executing its opening/closing operations is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus in which an upper frame constituting an apparatus main body is rotatable with respect to a lower frame.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus using an electrophotographic process technique, an electrostatic latent image is formed on a uniformly charged photoconductor by scanning light from an optical scanning device, and the electrostatic latent image is formed. The image is recorded by developing with toner and transferring and fixing the obtained toner image on the photoconductor to paper.

In such an image forming apparatus, when a paper jam occurs, the jammed paper is easily removed, or maintenance such as replacement of parts inside the apparatus is facilitated. There is one that is entirely divided into an upper frame and a lower frame. Conventionally, the following two have been proposed as configuration examples of such an apparatus.

First, Japanese Patent Laid-Open No. 3-291 shown in FIG.
In the example of the laser beam printer disclosed in Japanese Patent No. 674, the rear end of the upper frame 14 is pivotally supported by the rotary shaft 12 provided at the rear end of the lower frame 10 on the lower case side. An optical scanning device such as an optical deflector having a polygon mirror 16 is integrally provided on the upper frame 14. Then, the upper frame 14, together with the polygon mirror 16 and the like, is rotated about the rotary shaft 12 in the direction of arrow A in the figure to a position indicated by a chain double-dashed line in the figure, and the sheet feeding mechanism section of the lower frame 10 is rotated. The paper jammed in 18 can be removed, or the repair and maintenance of internal equipment can be performed.

Secondly, in the example of the electronic copying machine disclosed in Japanese Patent Laid-Open No. 63-92960 shown in FIGS. 10 to 12, as shown in FIG. 10, a unit of the lower frame 20 of the apparatus main body, The unit of the upper frame 22 is connected by a parallel link mechanism composed of four links 24, and the unit of the upper frame 22 is opened from the closed position shown by the chain double-dashed line in the figure to the open position shown by the solid line. It is configured to be operable.

Alternatively, in the copying machine illustrated in FIG. 11 and FIG. 12, the space between the unit of the lower frame 20 and the unit of the upper frame 22 of the apparatus main body is arranged at the positions corresponding to the four corners of the apparatus. The unit opening / closing holding mechanism 26 for elevating / lowering operation guide is connected and configured. In this copying machine, the upper frame 22 shown in FIG. 12 is separated from the lower frame 20 from the closed position where the upper frame 22 is united with the lower frame 20 shown in FIG. 11 by the urging force of the spring 28 of the unit opening / closing mechanism 26. The upper frame 22 and the lower frame 20 are configured to move up and down to the open position while maintaining the parallel state. The photoconductor drum 30, the charging device 32, the exposure device 34, the developing device 36, the transfer device 38, the peeling device 40, and the cleaning device 42 are mounted on the upper frame 22 configured as described above.

[0007]

In the structure shown in FIG. 9 described above, the upper frame 14 is fixed to the lower frame 10 when the upper frame 14 is opened by rotating the rotating shaft 12 about the rotating shaft 12. The optical scanning device is tilted, and the rotation center axis of the optical deflector having the polygon mirror 16 mounted in the optical scanning device is also tilted. Therefore, when the optical deflector having the polygon mirror 16 uses the air bearing as the bearing of the rotary shaft, the upper frame 14 can be opened before the rotation of the rotor provided with the polygon mirror 16 of the optical deflector is stopped. , Even if the power to the optical deflector is cut off, the rotor of the optical deflector will rotate by inertia while tilting,
Until the stop, the rotor rotates while the inner ring and the outer ring of the air bearing in the optical deflector are in contact with each other due to gravity. Therefore, there is a problem in that the peripheral surfaces of the inner ring and the outer ring that form the air bearing are damaged or worn, which deteriorates the performance of the optical deflector and shortens its life.

Further, in the structure shown in FIG. 10, since the length of each link 24 of the parallel link mechanism is limited by the depth width of the apparatus, the space between the lower frame 10 and the upper frame 14 cannot be widened. In addition, when the upper frame 14 is opened, the four links 24 are in the way, which makes it difficult to repair paper jams and perform maintenance work.

Further, in the structure shown in FIGS. 11 and 12, the unit of the upper frame 22 is supported by the four unit opening / closing holding mechanisms 26 and is moved up and down. Therefore, each of the four unit opening / closing holding mechanisms 26 is operated. Spring 28
The urging force must be changed and adjusted according to the position of the center of gravity of the unit of the upper frame 22, which is difficult to manufacture. At the same time, in order to smoothly lower the unit of the upper frame 22 to the closed position, it is necessary to push down the upper frame 22 so that the pushing force is uniformly applied to the four unit open / close holding mechanisms 26, which makes the operation difficult. There was a problem that became.

In addition to the above, in the configuration shown in FIGS. 9 to 12, the operator vigorously drives the upper frame 14 or 2.
When the opening / closing operation of 2 is performed, the impact at that time damages the air bearing of the optical deflector mounted integrally with the upper frame 14 and deteriorates the performance of the optical deflector.
There are problems such as shortening its life and causing other various devices to malfunction.

In consideration of the above facts, the present invention prevents various devices such as an optical deflector mounted on the upper frame from being damaged even if the upper frame is rotated and opened / closed with respect to the lower frame of the device body. In addition, it is an object of the present invention to newly provide an image forming apparatus in which an upper frame can be widely opened so that repair and maintenance such as paper jam can be easily performed.

[0012]

An image forming apparatus according to claim 1 of the present invention is an image forming apparatus in which an upper frame and a lower frame are separable from each other. And a posture maintaining means for rotating the optical device so as to move toward and away from the lower frame while maintaining the closed posture when opening and closing the upper frame. Characterize.

With the above-mentioned structure, various devices such as an optical deflector supported through the posture maintaining means when the upper frame is rotated around the shaft supporting means and opened / closed are operated. Since it can be opened and closed by moving in parallel to the lower frame so as to always maintain the posture of use, it can operate in the same manner as in the normal use state. For example, various devices such as an optical deflector together with the upper frame. Even when the rotor in various devices such as an optical deflector rotates by inertia when the air bearing is opened and closed, the axis of the air bearing tilts and the air bearing is damaged by the action of gravity acting on the rotor. You can avoid it. In addition, since the upper frame is rotated to open around the support shaft, the lower frame and the upper frame are wide open, and there is no interfering link member or strut in the opened part, so that the operator does not get a paper jam. It is possible to easily carry out repair and maintenance.

According to a second aspect of the invention, in the image forming apparatus according to the first aspect, there is provided a cushioning means for cushioning a shock transmitted to the optical device when the upper frame is opened and closed.

With the above-described structure, when the upper frame is opened and closed, impact force is applied to various devices such as the air bearing of the optical deflector, which requires high accuracy due to the action of the buffering means, and is damaged. You can prevent them from receiving it.

According to a third aspect of the present invention, in the image forming apparatus according to the first aspect, the support member has a lower bracket provided on the lower frame, the base end portion of which is pivotally supported, and the tip end portion of which is supported by the optical device. A pulley provided near the base end of the support member so as to be immovable with respect to the lower bracket; a pulley pivotally supported at the tip of the support member to rotate integrally with the optical device; The posture maintaining means is characterized by including a belt that is wound between a pulley on the base end side and a pulley on the tip end side of the support member and that constitutes a winding transmission mechanism.

With the above-mentioned structure, the pulley provided so as to be immovable with respect to the lower bracket when the support member pivots about the shaft of the base end portion thereof in conjunction with the opening / closing operation of the upper frame. A pulley pivotally supported on the tip of the support member is interlocked via a belt at an angle corresponding to the relative rotation with the support member, and the pulley and the optical device pivotally supported on the tip of the support member are integrated. And it will rotate,
The optical device moves in parallel to maintain the closed position of the upper frame at all times.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIGS.
This will be described with reference to FIG. The image forming apparatus main body according to the present embodiment has a substantially rectangular parallelepiped shape as a whole, and is configured to be separable into an upper frame 50 and a lower frame 52. Lower brackets 56 are erected on both side portions of the end portion of the lower frame 52 on the side opposite to the paper discharge port 54 (the right end portion in FIG. 1), and the lower bracket 56 faces the upper frame 50 side. A support shaft 58 is fixed between the ends so as to bridge.

Further, upper brackets 60 are provided so as to project at portions near both sides of an end portion of the upper frame 50 on the side opposite to the sheet discharge port 54 (right end portion in FIG. 1),
Each free end facing the lower frame 52 side is the support shaft 5.
8.

Further, one end of a rectangular plate-shaped support member 62 is pivotally supported at both ends of the support shaft 58.
Each of the support members 62 is connected to each of the upper brackets 60 adjacent to the support member 62 so as to rotate integrally around the support shaft 58.

Further, fixed pulleys 64 are fixedly mounted on the support shaft 58 so as to be immovable with respect to the lower bracket 56 at positions adjacent to the shaft support of each support member 62.

Further, a shaft member 66 is pivotally supported between both free ends of each support member 62 so as to bridge it.

A bracket 72 to which an optical scanning device 68 and a developing unit 70 are attached is provided at an intermediate portion of the shaft member 66.
Are fixed so as to rotate integrally with the shaft member 66.

Further, driven pulleys 74 are fixed to both ends of the shaft member 66, respectively. The driven pulley 74 has the same pitch circle diameter and the same number of teeth as the fixed pulley 64.

A timing belt 76 is wound between a pulley 64 fixed to the lower bracket 56 and a pulley 74 fixedly fixed to the bracket 72 of the optical scanning device 68 and the developing unit 70. It is interlocked by the winding transmission mechanism.

A torsion coil spring 78 is provided to urge the lower frame 52 so that the upper frame 50 pivotally supported by the support shaft 58 is opened to the open position. That is, the support shaft 58 is passed through the cylindrical hole of the coil of the spring 78, and the one end line portion of the spring 78 is engaged with the support pin 80 projecting on the side surface of the lower bracket 56, so that the spring 7
By engaging the other end line portion of 8 with the support pin 82 projecting from the side surface of the upper bracket 60, the upper frame 50
Is configured to receive a biasing force that rotates in the direction of arrow B in FIG. When the upper frame 50 is opened from the closed position shown in FIG. 2 to the open position shown in FIG. 1, the stopper portion 84 of the upper bracket 60 and the stopper portion 86 of the lower bracket 56 come into contact with each other, and the upper frame 50 is fixed. It is configured to be held in the open position of FIG.

Further, in the upper frame 50 rotated around the support shaft 58 to the closed position shown in FIG. 2, the latch member 88 mounted on the upper frame 50 has the lower frame 5
2 is detachably engaged with a locking pin 90 provided in
The upper frame 50 is held in the closed state.

The optical scanning device 68 attached to the bracket 72 of the upper frame 50 which is opened and closed in this way is composed of a laser light source, an optical deflector 92, a lens group 94, a folding mirror 96, etc., which are not shown.

The optical deflector 92 has an air bearing as a motor bearing, as shown in FIG. This air bearing is formed between a main shaft 100 that is erected on a stator-side base 98 of the motor, and a rotor-side outer ring 104 that is provided with a polygon mirror 102 that rotates around this main shaft. That is, this air bearing is
00, a spiral groove 106 is cut, and an outer ring 104 is inserted and inserted in the groove 106 with a predetermined gap. This controls the energization of the coil 108 on the stator side, and when the polygon mirror 102 integrated with the rotor is rotated by the action of the magnetic force acting between the coil 108 on the stator side, the outer ring 1 of the rotor is rotated.
Due to the rotation of 04, the surrounding air causes the main shaft 100 and the outer ring 1 to move.
04, the air pressure in the space between the main shaft 100 and the outer ring 104 increases, and the outer ring 104 is supported by the main shaft 100 in a non-contact manner.

As shown in FIGS. 1 and 2, the developing unit 70 attached to the bracket 72 of the upper frame 50 includes a photoconductor 112, a charger 114, a developing unit 116,
The developing unit 70 includes a transfer charger 118, a cleaning device 120, and the like, and the developing unit 70 is positioned and installed at a predetermined position corresponding to the optical scanning device 68.

Further, the lower frame 52 has a sheet feeding device 1
22 and a fixing device 124 are arranged.

In the image forming apparatus of the present embodiment configured as described above, the surface of the photoconductor 112 uniformly charged by the charger 114 is exposed by the optical scanning device 68 according to the information. Electrostatic latent image is formed by the developing device 116.
By this, the electrostatic latent image is developed into a toner image, and at the same time, it is transferred onto the paper sent from the paper feeding device 122 at the transfer portion where the transfer charger 118 is located. The sheet is fixed by the fixing device 25 while the toner image is placed on the sheet, and the sheet is ejected to the outside of the apparatus main body.

Further, in the image forming apparatus of this embodiment,
As shown in FIG. 2, in a usable state in which the upper frame 50 of the apparatus main body is closed, the optical scanning device 68 is in a horizontal posture, and the optical deflector 92 provided in the optical scanning device 68 has its air bearing. Main shaft 100 and outer ring 104 that configure the
The rotation center axis of and is in the vertical posture.

When a paper jam occurs inside the main body of the image forming apparatus, or when the internal equipment is repaired or maintained, the upper frame 50 is opened to perform the work.

To open the upper frame 50, first, the latch member 88 is removed from the locking pin 90. Then, the urging force of the torsion coil spring 78 causes the upper frame 50 to rotate about the support shaft 58 in the direction of arrow B shown in FIG. 2 and shift to the open state shown in FIG. At this time, the timing belt 76, which rotates integrally with the upper frame 50 in the direction of the arrow B around the pulley 64 fixed to the lower bracket 56, is wound while changing the winding position on the fixed pulley 64. That is, it means that the pulley 64 rotates relative to the upper frame 50. Therefore, the pulley 74, which is interlocked with the timing belt 76, is rotated in the direction of arrow C in FIG. 2 by the amount of rotation of the upper frame 50 about the support shaft 58 (note that the fixed pulley 64 and the bracket). Since the pulley 74 that rotates integrally with 72 has the same pitch circle diameter and the same number of teeth, this interlocking operation corresponds to one to one).

As a result, as the upper frame 50 rotates in the direction of arrow B, the optical scanning device 68 of the bracket 72 is moved.
The developing unit 70 and the developing unit 70 are rotated in the direction of arrow C by the posture maintaining means including the two pulleys 64 and 74 and the timing belt 76, and maintain the same horizontal posture as in the use state of FIG. Further, when the upper frame 50 is rotated in the direction opposite to the arrow B to close it, the optical scanning device 6 is also operated as described above.
8 and the developing unit 70 are indicated by arrow C by the posture maintaining means.
It rotates synchronously in the opposite direction, and maintains the same horizontal posture as in the use state of FIG.

Therefore, even when the frame 50 is opened and closed, the optical deflector 9 provided in the optical scanning device 68 is provided.
Reference numeral 2 is a main shaft 100 and an outer ring 1 which constitute the air bearing.
The central axis of rotation with respect to 04 maintains the vertical posture, and even if the optical deflector 92 is coasting, the upper frame 5
Even if 0 is opened and closed, the rotor does not rotate in a state where the main shaft 100 and the outer ring 104, which constitute the air bearing of the optical deflector 92, are in contact with each other due to gravity, and the main shaft 100 and the outer ring 104 are damaged or worn. Therefore, the performance deterioration of the optical deflector 92 can be prevented.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the upper bracket 60 of the upper frame 50 and the optical scanning device 6
8 and the developing unit 70 portion are movable relative to each other, and the impact force when the upper frame 50 is opened / closed is not transmitted to the optical scanning device 68 and the developing unit 70 portion.

Therefore, in the second embodiment, the support shaft 5 is provided between the two lower brackets 56 of the lower frame 52.
8 is fixed to bridge.

The free ends of the two upper brackets 60 of the upper frame 50 are independently supported by the support shaft 58.

Further, one end of a rectangular plate-shaped support member 62 is independently pivotally supported at both ends of the support shaft 58. In addition, at each position adjacent to the shaft support of each support member 62, a fixed-side pulley 64 is provided.
It is fixed to the support shaft 58 and arranged so as to be immovable with respect to 6.

Further, a shaft member 66 is pivotally supported between both free ends of each support member 62 so as to bridge it.

A bracket 72 to which an optical scanning device 68 and a developing unit 70 are attached is provided at an intermediate portion of the shaft member 66.
Are fixed so as to rotate integrally with the shaft member 66.

Further, pulleys 74 on the follower side are fixed to both ends of the shaft member 66. The driven pulley 74 has the same pitch circle diameter and the same number of teeth as the fixed pulley 64.

The timing belt 76 is provided between the pulley 64 fixedly fixed to the lower bracket 56 and the pulley 74 fixedly fixed to the bracket 72 of the optical scanning device 68 and the developing unit 70.
Is wound and linked.

As described above, a torsion coil spring 78 is provided to urge the lower frame 52 so that the upper frame 50 pivotally supported by the support shaft 58 is opened to the open position. That is, the support shaft 58 is passed through the cylindrical hole of the coil of the spring 78, and the one end wire portion 79 of the spring 78 is engaged with the support pin 80 projecting from the side surface of the lower bracket 56.
An intermediate portion of the other end wire portion 81 of the spring 78 is engaged with a support pin 82 projecting from the side surface of the upper bracket 60. Further, a receiving recess 83 is formed at the tip of the other end wire portion 81 of the spring 78. The receiving concave portion 83 is configured to be engageable with and disengageable from the engaging pin 126 provided on the side surface of the support member 62. That is, the engagement pin 126 is
The receiving recess 83 of the spring 78 is arranged on the locus of rotation in the direction of arrow B, and in the use state shown in FIG.
The other end wire portion 81 of the spring 78 is arranged at a position where the other end wire portion 81 of the spring 78 comes into contact after rotating by a predetermined rotation angle in the rotation direction indicated by the arrow B. The torsion coil spring 78 has a biasing force that causes the biasing force to open the entire upper frame 50 including the optical scanning device 68 and the developing unit 70 mounted on the tip of the support member 62 about the rotation center shaft 58. It is configured.

The bottom plate 53 of the lower frame 52 has a cylinder 13 in the damper 128 for absorbing impact force.
The root end of 0 is pivotally supported. Furthermore, this damper 12
The distal end portion of the telescopic rod 132 of No. 8 is pivotally supported by the intermediate portion of the support member 62, and a buffering means is configured to rotate the support member 62 around the support shaft 58 smoothly and gently.

Further, the supporting member 62 is stopped at the use position shown in FIG. 4 by the damper 128 or a stopping means such as a stopper (not shown) so as to position the optical scanning device 68 and the developing unit 70. There is.

A plate spring 134 is attached to the upper frame 50 at a predetermined position on the side surface of the upper bracket 60 as an elastic stopper. The tip of the leaf spring 134 is bent into a substantially U shape to form an abutting portion 136 that abuts the intermediate side of the support member 62. The support member 62 rotates about the support shaft 58 in the direction of arrow B. Moving, upper frame 5
When the contact portion 136 of the leaf spring 134 elastically abuts the support member 62 when the cover member 51 of 0, the support member 62 is prevented from colliding with the cover portion 51. There is.

Next, the operation and operation of opening and closing the upper frame 50 in the image forming apparatus according to the second embodiment having the above-described structure will be described.

First, a case where the upper frame 50 is opened while the image forming apparatus shown in FIG. 4 is in use will be described. To open the upper frame 50, the latch member 88 is disengaged from the locking pin 90. Then, the urging force of the torsion coil spring 78 causes the cover portion 51 of the upper frame to rotate in the direction of arrow B in the drawing to reach the small rotation position shown in FIG. At the position shown in FIG. 5, the receiving concave portion 83 of the torsion coil spring 78 contacts the engaging pin 126, and the force of the other end wire portion 81 of the spring 78 to urge in the direction of arrow B causes the support member 62 portion and the cover portion. The entire upper frame 50 including 51 rotates in the direction of arrow B, and the stopper portion 86 of the lower bracket 56 and the stopper portion 84 of the upper bracket 60 come into contact with each other,
The state shown in FIG. 6 is reached in which the rotation of the upper frame 50 in the arrow B direction is stopped. The entire upper frame 50 is shown in FIG.
The operation of shifting from the state of FIG. 6 to the state of FIG.
Since the damper 128 is controlled so as to be gentle, the operation can be performed smoothly and slowly without being subjected to strong acceleration or impact.

During this operation, the lower bracket 56
The stationary pulley 64 and the support member 6
2 will be rotated relative to each other. Therefore, the pulley 74, which is interlocked via the timing belt 76 and rotates integrally with the bracket 72 provided with the optical scanning device 68 and the developing unit 70, synchronizes with the rotation angle of the support member and is indicated by an arrow C in the figure. Rotate in the direction. Therefore, two pulleys 6
The optical scanning device 68 and the developing unit 70 are separated from each other by the posture maintaining unit composed of 4, 74 and the timing belt 76.
While maintaining the same horizontal posture as that in the use state, it rises in parallel and reaches the open state of the upper frame 50 shown in FIG. At this time, even if the operator vigorously opens the cover 51,
Only the cover portion 51 only opens vigorously, and the support member 62 portion opens slowly by the action of the damper 128, so that the optical scanning device 68 and the like are not impacted by the rotating operation.

In the open state of the upper frame 50 shown in FIG. 6, the cover portion 51 of the upper frame 50, the optical scanning device 68, and the developing unit 70 are largely disengaged from above the lower frame 52, and the link is established. Since there is no member or open / close holding mechanism and the opening is large, it is possible to easily carry out repairs and maintenance of paper jams and the like for each device inside the apparatus main body without being disturbed.

Next, the case where the open state of the upper frame 50 shown in FIG. 6 shifts to the closed state shown in FIG. 4 will be described. In this shifting operation, the user moves the cover portion 51 into the spring 78.
It is executed by the operation of pushing in the direction opposite to the arrow B against the urging force of.

First, from the state shown in FIG. 6, the upper frame 5
When the 0 cover portion 51 is pushed in the direction opposite to the arrow B, the support pin 82 of the upper bracket 60 rotates the other end wire portion 81 in the direction opposite to the arrow B by a small angle against the biasing force of the spring 78. The support member 62 supported by the damper 128 by this operation is
The spring 7 pressing the engaging pin 126 in the direction of arrow B
Since the receiving recess 83 of 8 is removed, the rod 132 of the damper 128 is pushed into the cylinder 130 by the weight of the optical scanning device 68 supported by the support member 62 and the developing unit 70, and the arrow B The rotation starts in the opposite direction.

In the state shown in FIG. 7, the supporting member 62 which moves slowly approaches the cover 51 rotated swiftly, and the leaf spring 134 elastically contacts the supporting member 62.

From the state shown in FIG. 7, the cover portion 51 is further pushed down so as to rotate in the direction opposite to the arrow B, and the cover portion 51 is closed to the lower frame 52 shown in FIG. The latch member 88 is engaged. When the cover portion 51 is pushed down, the leaf spring 134 elastically pushes down the support member 62 against the reaction force of the damper 128, and no impact force is applied to the optical scanning device 68 and the developing unit supported by the support member 62. To do so.

In the state shown in FIG. 8, since the cover portion 51 is stopped, the leaf spring 134 does not push the support member 62 further in the direction opposite to the arrow B.
2 is smoothly and slowly rotated in the direction opposite to the arrow B while receiving the reaction force of the damper 128 due to the own weight of the optical scanning device 68 and the developing unit 70 applied to the support member 62, as shown in FIG. It automatically returns to the used state. In addition,
Even if the operator closes the cover portion 51 vigorously, the supporting member 62, the optical operating device 68, and the developing unit 70 are not being impacted because they are being lowered by their own weight.

During the operation of shifting from the open state of FIG. 6 to the closed state of FIG. 4, the operation opposite to that described above is performed by the posture maintaining means including the two pulleys 64 and 74 and the timing belt 76. Thus, the optical operating device 68 and the developing unit 70 supported by the supporting member 62 can be lowered while maintaining the same horizontal posture as in the use state.

Therefore, during the opening / closing operation of the upper frame 50, the rotary shaft of the air bearing of the optical deflector 92 is not tilted, so that the rotor of the optical deflector rotating by inertia is stopped. The main shaft of the air bearing and the outer ring will not rotate while they are in contact with each other due to gravity,
Moreover, since the impact due to the opening / closing operation of the upper frame 50 is configured not to be directly transmitted to the optical scanning device 68, it is possible to prevent the air bearing portion from being damaged, deteriorating its performance, and shortening its service life. , Can keep stable quality images.

Since the configuration, operation, and effect of the second embodiment other than those described above are the same as those of the first embodiment, the same members are designated by the same reference numerals, and the details thereof will be given. Description is omitted.

[0062]

As described above, in the image forming apparatus of the present invention, even if the upper frame is opened and closed with respect to the lower frame of the apparatus body, various devices mounted on the upper frame such as an optical deflector are damaged. Since the upper frame of the image forming apparatus can be widely opened, it has an excellent effect that repair and maintenance such as paper jam can be easily performed.

[Brief description of drawings]

FIG. 1 is an overall vertical cross-sectional view showing a state where an upper frame of an image forming apparatus according to a first embodiment of the present invention is opened.

FIG. 2 is an overall vertical cross-sectional view showing a usage state of the image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is an exploded vertical cross-sectional view showing an optical deflector mounted on the upper frame of the image forming apparatus according to the first embodiment of the present invention, taken out and shown.

FIG. 4 is an overall vertical sectional view showing a usage state of an image forming apparatus according to a second embodiment of the present invention.

FIG. 5 is an overall vertical sectional view showing an operation of starting opening of the upper frame with the latch member released in the image forming apparatus according to the second embodiment of the present invention.

FIG. 6 is an overall vertical sectional view showing a state in which an upper frame is completely opened in an image forming apparatus according to a second embodiment of the present invention.

FIG. 7 is an overall vertical cross-sectional view showing a state in which an image forming apparatus according to a second embodiment of the present invention starts to push a cover portion of an upper frame in a closing direction.

FIG. 8 is an overall vertical cross-sectional view showing a state in the image forming apparatus according to the second embodiment of the present invention, in which only the cover portion of the upper frame is closed and the closing operation is almost completed.

FIG. 9 is an explanatory diagram showing a schematic configuration of a conventional printer that can be separated into two units.

FIG. 10 is an explanatory diagram showing a schematic configuration of a conventional electronic copying machine that can be separated into two units.

FIG. 11 is an explanatory diagram showing another schematic configuration of a conventional electronic copying machine that is separable into two units in use.

FIG. 12 is an explanatory diagram showing another schematic configuration of a conventional electronic copying machine which is separable into two units in an open state.

[Explanation of symbols]

 50 Upper Frame 51 Cover Part 52 Lower Frame 56 Lower Bracket 58 Support Shaft (Axis Supporting Means) 60 Upper Bracket 62 Supporting Member (Posture Maintaining Means) 64 Pulley (Posture Maintaining Means) 66 Shaft Member (Posture Maintaining Means) 68 Optical Scanning Device (Optical device) 70 Developing unit 74 Pulley (posture maintaining means) 76 Timing belt (posture maintaining means) 92 Optical deflector (optical device) 78 Spring (buffering means) 80 Support pin (buffering means) 82 Support pin (buffering means) 126 Engagement Pin (Cushioning Means) 128 Damper (Cushioning Means) 134 Leaf Spring (Cushioning Means)

Claims (3)

[Claims] 1. An image forming apparatus in which an upper frame and a lower frame are separable from each other, and a shaft supporting means for rotatably supporting the upper frame with respect to the lower frame; An image forming apparatus, comprising: a posture maintaining unit that rotates an optical device so as to move toward and away from the lower frame while maintaining a closed posture during an opening / closing operation. 2. The image forming apparatus according to claim 1, further comprising a cushioning device for cushioning a shock transmitted to the optical device when the upper frame is opened and closed. 3. A support member, the base end portion of which is pivotally supported by a lower bracket provided on the lower frame, and the optical device being pivotally supported by the tip end thereof, and the lower bracket portion near the base end portion of the support member. A pulley provided immovably with respect to the support member, a pulley pivotally supported at the tip of the support member so as to rotate integrally with the optical device, a pulley on the base end side of the support member, The image forming apparatus according to claim 1, further comprising: a belt that is wound between a support member and a pulley on a tip end side thereof to form a winding transmission mechanism, and the posture maintaining unit.