JPH0223853B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus with a movable document table whose main body can be opened in sections. The present invention will be described below by taking as an example a copying machine with a movable document table that can be divided into an upper and lower machine frame.

The present invention includes a document table on which a document is placed and moved in order to form an image, and an upper body that can be opened relative to the center of rotation around one end in the direction of movement of the document table. In a document platen movable image forming apparatus having a lower main body and a movable locking means for preventing the upper main body and the lower main body from being opened when the upper main body and the lower main body are closed, The locking means is in a movable state without being prevented from moving by the document table at the position where the document table is retracted, thereby permitting release of the opening prevention, and a position opposite to the retracting direction with respect to the retracted position. The locking device is characterized in that the operation of the locking device is controlled according to the position of the document table so that the movement of the locking device is blocked by the document table, thereby prohibiting release of the opening prevention. This is a moving document table type image forming apparatus.

FIG. 1 is a schematic view of a moving document table type copying machine to which the present invention is applicable, as seen from the left side, FIG. 2 is a perspective view thereof, and FIG. 3 is a right side view thereof.

In FIG. 1, 1, 2, 3, 4, and 5 are charging, exposing, developing, transferring, and cleaning members, respectively, and are process elements for forming images arranged around the drum 6 (indicated by a dashed line). It is. Further, the transfer material is sent out from the cassette 7 by a delivery roller 8, further transported by transport rollers 9 and 10, and after passing through the transfer position 4, it is delivered to the delivery roller 1.
1 and 12, the paper is ejected into the tray 13. Further, in this copying machine, by releasing the engagement between the lever 14 and the engaging portion 15, the upper machine frame 18 is moved around the upper machine frame 17 with the force of the push-up member 16 as the center of rotation.
can be opened (as shown in FIGS. 1 and 3). As shown in the figure, when the machine frame is split open, the cassette 7, drum 6, lower transport roller 8, transfer charger 4, and lower paper ejection roller 12 remain below.
The charging, exposure, development, and cleaning processes, the upper transport roller 9, and the upper paper discharge roller 11 are lifted upward together with the upper machine frame 18. That is, as shown in FIG. 1, the machine frame can be vertically divided into an upper machine frame 18 ₁ and a lower machine frame 18 ₂ with the paper feed conveyance path as a boundary.

Therefore, if a paper jam occurs, for example, the machine frame can be opened across the paper feed and conveyance path, making it possible to remove the jammed paper very easily. Furthermore, when performing repairs or inspections, the opening of the machine frame allows for a wider space for cleaning or processing drums, etc., making operations easier.

However, in such a copying machine in which the upper and lower machine frames can be opened, if the machine frame is opened inadvertently, for example, in a copying machine with a movable document table as shown in the figure, the document table 19 is moved to the upper machine frame 18. When ₁ is released, it slides down the slope and stops with a shock when it comes into contact with other parts. At that time, there is a possibility that the impact may damage the document table 19 or disrupt its movement accuracy. Also,
In a copying machine with a moving optical system, there is a risk that the optical system may be damaged or its movement accuracy may be disrupted.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to reliably prevent damage to the document table or loss of accuracy when the main body is opened in sections.

That is, the present invention, which achieves the above object, is configured such that the main body can be opened only when, for example, the document table is retracted to a predetermined position near the end where it slides when the main body is opened. Thereby, the present invention can prevent the movable body from moving accordingly when the main body is opened, and can prevent damage to the movable body or loss of accuracy.

Hereinafter, one embodiment of the present invention will be described in detail using the drawings. FIG. 4 is a side view showing the main parts of an embodiment of the present invention, and FIG. 5 is a perspective view of the main parts.

In the figure, on the fixed part 18a of the upper machine frame ₁₈₁ ,
A support shaft 20 is rotatably attached. A lever 21 is fixed to the support shaft 20 substantially at the center thereof, and a lock arm 22 is fixed to the vicinity of the end thereof.
When the main body is divided and opened, when this lever 21 is pulled in the direction of arrow a, the support shaft 20 also rotates in conjunction with the swinging of this lever 21. Therefore, this support shaft 20
Due to this rotation, the lock arm 22 fixed to this support shaft 20 also rotates in the direction of arrow a. At this time, a pin 2 is attached to the end of the lock arm 22.
3 is connected to a connecting bar 24, and the other end of this connecting bar 24 is also connected to a stop lever 26 by a pin 25. Further, this stop lever 26 is capable of swinging around a shaft 27, and the abutment portion 26a at the tip thereof swings to open the opening provided in the document table support plate 28.
It has a structure that protrudes from 9.

First, with the document table 19 retracted in the sliding direction by opening the main body, that is, at the predetermined position B.
A case will be explained in which the main body is opened with the main body moved further in the opening direction. In the case of this embodiment, this predetermined position B is provided near the end of the movement of the document table. When the main body is divided and opened, when the lever 21 is pulled in the direction of arrow a, the support shaft 20 also rotates in conjunction with the swinging of the lever 21. At that time, lock arm 22
Even if the lever 24 connected to the end of the stop lever 24 moves in the direction of arrow b and swings the stop lever 26 about the shaft 27, the abutting portion 26a remains open without being obstructed. Since it can protrude from 29 and swing, the lock arm 22 also swings in conjunction with the rotation of the support shaft 20. Therefore, when the lock arm 22 swings in the direction of arrow a, the engaging portion 22 provided at the tip of the lock arm 22
a is disengaged from the engaging portion 18 ₃ of the lower machine frame 18 ₂ . By releasing this engagement, the upper machine frame 18 ₁
is lifted upward by the pushing force of the pushing member 16, and the main body is opened. Therefore, when the main body is opened, the upper machine frame ₁₈₁ is tilted, but since the document table 19 has been retracted in advance in the opening direction (as shown in FIG. 3), the document table 19 hardly slides down. Therefore, the impact can be extremely reduced, and the document table 19 will not be damaged or its accuracy will be lost.

Next, a case will be described in which the main body is attempted to be opened before the document table 19 is retracted from the predetermined position B in the feeding direction. In this case, if you open the main body carelessly, the document table 19 will slide down a long distance, so
It may stop with an impact, resulting in the damage or loss of accuracy. Therefore, in this embodiment, even if an attempt is made to pull the lever 21 in the direction of arrow a in order to open the main body, the swinging of the lever 21 is blocked to prevent the main body from opening.
That is, even if an attempt is made to pull the lever 21 in the direction a, the abutting portion 26a of the stop lever 26 abuts against the document table 19 located above the opening 29, and the stop lever 26 is prevented from swinging. In this case, the lever 24 cannot move in the direction of arrow b, and therefore the lock arm 22 cannot swing in the direction of arrow a, and the lower machine frame 18 ₂ cannot move in the direction of arrow a.
The engagement with the engagement portion 18 ₃ is never released.
Therefore, at this time, the lever 21, which is fixed to the same shaft 20 as the lock arm 22, is also prevented from swinging.
In other words, even if you try to open the main body when the document table 19 has not been retracted to the predetermined position B, the lever 2
1 cannot swing and the main body will not open. Therefore, even if an attempt is made to open the main body while the original table 19 is not retracted, the main body cannot be opened, and therefore damage to the original table or loss of accuracy can be prevented.

In the copying machine used in this embodiment, as shown in FIG. 6, the upper and lower machine frames can be closed by pushing down the document table support plate 28.

As described above, the present invention enables the image forming apparatus main body to be opened by disengaging the engaging member only when the original table retreats in the sliding direction due to a predetermined main body opening. . Thereby, the present invention prevents damage or loss of accuracy due to movement of the document table when the main body is released.

[Brief explanation of drawings]

FIG. 1 is a schematic view from the left side of a moving document table copying machine to which the present invention can be applied, FIG. 2 is a perspective view thereof, FIG. 3 is a right side view thereof, and FIG. FIG. 5 is a side view showing the main parts of the embodiment, FIG. 5 is a perspective view of the main parts, and FIG. 6 is a side view showing the state when the upper and lower machine frames of the copying machine are closed. In the figure, 14... Lever, 15... Engaging portion, 16... Pushing member, 18 ₁ ... Upper machine frame, 18 ₂ ... Lower machine frame, 19... Original table, 20... Support shaft, 21 ……
Lever, 22...Lock arm, 24...Connection bar, 26...Stop lever, 26a...Abutting portion, 28...Original table support plate, 29...Opening.

Claims (1)

[Scope of Claims] 1. A document table on which a document is placed and moved, an upper main body and a lower main body that can be opened relatively with respect to the direction of movement of the document table, with the vicinity of one side end being the center of rotation, and an upper part. In an image forming apparatus having a movable document platen, the image forming apparatus has a main body and a locking means having a lock lever portion for opening the lower body, the locking device has a movable abutting portion that comes into contact with the document platen, and the locking device has a movable abutting portion that contacts the document platen, When the lower body is closed and the document table is retracted toward the center of rotation, the contact portion does not come into contact with the document table and the lock lever remains in a movable state without being prevented from moving. This allows the upper and lower main bodies to be opened, and when the document table is in the opposite direction to the retracted direction with respect to the above-mentioned retracted position, the abutting part contacts the document table and the movement of the lock lever is suppressed, so that the upper part 1. An image forming apparatus with a movable document table, characterized in that movement of a lock lever section is suppressed depending on the position of the document table so as to prohibit opening of the main body and the lower main body. 2. The document table movable image forming apparatus according to claim 1, wherein the upper main body and the lower main body are opened with a paper feed conveyance path as a boundary.