JPH0251190B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for fixing a pressure bonding plate to an original platen in an image forming apparatus such as an electrophotographic copying apparatus, for example, for bringing an original to be copied into close contact with an original placing surface of a copying machine. It is related to.

Conventionally, the crimp plate and document table have two methods: the crimp plate has a hinge part for opening and closing the crimp plate, and the foot of this hinge is detachably fixed to the document table, or the hinge part is fixed to the document table with screws. However, with these methods, making it easier to attach and detach the crimp plate increases the looseness between the crimp plate and the document table. , the crimp plate tends to move during copying,
This increases the risk of the document moving, especially in electronic copying devices with a movable document table. This makes it difficult to remove the crimp plate, for example, requiring the use of a tool to remove the hinge portion, resulting in a mechanism that is difficult for users to use. In addition, providing a hinge member as described above between the crimp plate and the document table increases the overall height of the document table and the crimp plate, which is a major hindrance to the miniaturization of copying machines that has been increasing in recent years. There were drawbacks such as. The present invention eliminates the above-mentioned drawbacks of the conventional example, makes it easier to attach and detach the document table and the pressure bonding plate, and also makes it possible to securely fix the pressure bonding plate to the document table. It is an object of the present invention to provide a fixing device for a document pressure bonding plate that can be made thinner.

In order to achieve the above object, the document pressure plate fixing device according to the present invention has a structure in which a document pressure plate is fixed to a document placement table on which a document is placed and moves in a predetermined direction for exposure. In the fixing mechanism,
A first engaging portion provided on either one of the document pressure bonding plate and the document mounting table, and a direction orthogonal to the predetermined direction using elastic deformation to the first engaging portion provided on the other side. a fixing means consisting of a protrusion that is removably engaged with the document pressure plate, a second engagement section provided on either one of the document pressure bonding plate and the document placement table, and a second engagement section provided on the other and provided with the second engagement section; and a positioning protrusion that is engaged with the mating part, and the fixing means is configured such that in the engaged state, the first engaging part and the protrusion are perpendicular to the predetermined direction due to elastic force. The positioning means is engaged when the fixing means is engaged, and is configured to restrict movement in the predetermined direction.

The present invention will be described in detail below based on embodiments shown in the drawings. Reference numeral 1 denotes an original pressure bonding plate having a transparent member such as a glass plate and its frame. Inside the copying machine main body 2, a light source 3 for performing exposure,
A short focus imaging element array 5 for forming an image of the original on the document mounting table 1 on the photoreceptor drum 4, a developing device 6 for visualizing the latent image on the photoreceptor drum 4, and paper feeding from a paper feeding system 7. Mechanisms such as a transfer charger 9 for transferring the developed image on the photoreceptor drum 4 to the transferred transfer paper 8 and a fixing device 10 for fixing the unfixed image on the transfer paper 8 are incorporated. . Reference numeral 11 denotes an original pressure bonding plate superimposed on the upper surface of the document placement table 1, and the document (not shown) is pressed onto the document placement table 1 by this pressure bonding plate 11.
It is something that is pushed upwards.

Further, one side of the pressure bonding plate 11 is attached to the original table 1 via a connecting mechanism so as to be openable and closable, and this connecting mechanism will be explained with reference to FIGS. 2 to 5. That is, at the edge of the original table 1, there is a first notch 12 for fitting, and a first fitting recess 13 continuously formed on both sides of the notch 12.
the engaging portion 14, the wide hole 15, and the wide hole 15.
It has an engagement hole 17 as a second engagement portion, which is formed by a narrow hole 16 formed subsequently to the engagement hole 17 . The crimp plate 11 also includes a protrusion 18 that is engaged in the notch 12, and engaging pieces that extend on both sides of the protrusion 18 and that are engaged in the fitting recess 13. 19, and the aforementioned engagement hole 1.
It has a positioning protrusion 21 that is engaged with 7.

The above is the configuration of this embodiment.Next, its operation will be explained.When copying is performed using a copying machine having this configuration, the document table 1 first moves to the left end, and the exposure light source 3 When the light turns on, the document table will scan to the right. At the same time, a latent image is formed on the photoreceptor drum 4 through the short focus imaging element array. After the document mounting table 1 finishes scanning the document, it is reversed, returns to its initial state, the home position, and stops. This copying operation is well known, but next we will discuss the gist of the embodiment, which is the document placement table 1 and the pressure bonding plate 1.
1, the protrusion 20 and the first engagement portion 14 formed on the pressure bonding plate 11 and the original table 1 are made of an elastically deformable material such as polypropylene. Therefore, in order to attach the pressure bonding plate 11 to the document placement table 1, the pressure bonding plate 11 is first positioned on the document placement table 1, and then the protrusion 18 of the protrusion 20 is fitted into the notch 12. Also, the positioning protrusion 21 is positioned so as to be inserted into the wide hole 15 of the engagement hole 17. Therefore, when the crimp plate 11 is shifted so that the engagement piece 19 is engaged in the fitting recess 13, the engagement piece 19
is elastically deformed, and the edge of the fitting recess 13 passes over the inclined surface of the engaging piece 19. When the engaging piece 19 finally matches the fitting recess 13, the original pressure bonding plate 11 is moved vertically and vertically in the drawing. Positioning in the thickness direction is performed. Also, at this time, since the positioning protrusion 21 is guided into the narrow hole 16 of the engagement hole 17, lateral positioning is also performed at the same time, and the pressure bonding plate 11 is placed on the original table 1 by the engagement piece 19. It is fitted and fixed without any looseness due to its elasticity. When the crimp plate 11 is removed from the original table 1, pressing the upper part of the protrusion 20 of the crimp plate 11 loosens the engagement between the engagement piece 19 and the fitting recess 13. The plate 11 can be moved and removed from the original table 1. The embodiment shown in FIGS. 6 and 7 shows other embodiments of the embodiment,
In FIG. 6, the two positioning protrusions 21 in the above embodiment are replaced with positioning protrusions 21', and the two engaging holes 17 are replaced with one positioning engaging hole 1.
It is changed to 7'. In addition, the embodiment shown in FIG.
Engagement holes 17' and positioning ridges 21' are formed near both sides of the document placement table 1 and the pressure bonding plate 11, and engagement portions are formed at the intermediate portions of both the engagement holes 17' and the intermediate portions of the ridges 21'. 14 and a protrusion 20 are formed. Therefore, these embodiments also have the same effects as those described in the first embodiment.

As described above, the present invention allows the pressure bonding plate to be securely fixed to the original table without any wobbling without providing a separate member for joining, and furthermore, the two members can be attached and detached by hand without the need for any tools. It has the advantage that it can be easily performed with a pressing force of .

[Brief explanation of drawings]

The drawings all show a fixing mechanism for a document pressure bonding plate according to the present invention; FIG. 1 is a schematic diagram of a copying machine equipped with the fixation mechanism; FIGS. 3A and 3B are a plan view and a side view of the original table, FIG. 4 is an enlarged explanatory view showing the relationship between the engagement hole and the positioning protrusion, and FIG. 5 is the engagement part and Enlarged perspective view showing the protrusion, No. 6
Figures A and B are plan views of the main parts of a pressure bonding plate and a document mounting table according to another embodiment of the present invention, and FIGS. FIG. 1...Document placement table, 2...Copier main body, 3...
Light source, 4... Photosensitive drum, 5... Short focus combined image element array, 6... Developing device, 7... Paper feeding system, 8...
...Transfer paper, 9...Transfer charger, 10...Fuser,
11... Original pressure bonding plate, 12... Notch, 13...
Fitting recess, 14... Engaging portion, 15... Wide hole, 1
6...Narrow hole, 17...Engagement hole, 18...Protrusion,
19...Engaging piece, 20...Protrusion, 21...Positioning protrusion, 21'...Positioning protrusion.

Claims (1)

[Scope of Claims] 1. In an original pressure bonding plate fixing mechanism for fixing a document pressure bonding plate to a document placement table that places a document and moves in a predetermined direction for exposure, either of the document pressure bonding plate or the document placement platform is provided. A first engaging portion provided on one side, and a first engaging portion provided on the other side.
a fixing means comprising a protrusion that is removably engaged with the engaging portion from a direction perpendicular to the predetermined direction using elastic deformation; a second engaging portion provided on the other side;
and a positioning protrusion that is engaged with the engaging part of the fixing means, wherein the first engaging part and the protruding part are moved in the predetermined direction by elastic force in the engaged state. , the positioning means is engaged when the fixing means is engaged, and is configured to restrict movement in the predetermined direction. mechanism.