JPH0714769B2 - Paper feed mechanism with copy paper cassette - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a paper feed mechanism including a copy paper cassette detachably mounted in a cassette receiving portion defined in a housing of a copying machine.

<Prior Art> Conventionally, a paper feed mechanism in which a cassette receiving portion is defined in a housing of a copying machine and a copy paper cassette containing copy paper is detachably mounted in the cassette receiving portion has been widely put into practical use. Has been done. In the paper feed mechanism of such a form,
The copy paper cassette has a cassette body having an opening formed at the front end of the bottom wall and a mounting plate mounted inside the cassette body so as to be rotatable around the rear end as a fulcrum. It is placed on the plate. Further, a press contact mechanism is arranged in the copying machine housing in relation to the cassette receiving portion, and the press contact mechanism acts on the mounting plate through an opening formed in the cassette body (in the actuating state). In some cases, the uppermost copy paper on the mounting plate is pressed against the feed roller by the action of the pressure contact mechanism, so that the copy paper can be supplied from the copy paper cassette) and the non-operating state in which the copy paper is separated from the mounting plate. (When in the non-acting state, the press contact mechanism can be retracted from the inside of the cassette body to allow the copy paper cassette to be detached from the cassette receiving portion). A pressure contact release lever mechanism is additionally provided in association with the above-described pressure contact mechanism, and the pressure contact mechanism is held in the inactive state by operating the pressure contact release lever mechanism (note that the copy paper cassette is When it is detachably attached to the cassette receiving part, the pressure contact mechanism is held in an operating state).

Thus, in the conventional paper feed mechanism of the above-mentioned form,
The following inconveniences exist. That is, when the copy paper cassette is detachably attached to the cassette receiving portion, the pressure contact mechanism is kept in the operating state, while when the copy paper cassette is detached from the cassette receiving portion, the pressure contact release lever mechanism is operated to perform the pressure contact. The mechanism must be deactivated, and then the copy paper cassette must be removed from the cassette receiving portion, and therefore the operation of removing the copy paper cassette from the cassette receiving portion is complicated. Further, since there is a pressure contact release lever mechanism which holds the pressure contact mechanism in a non-acting state in relation to the pressure contact mechanism, the configuration of the entire paper feed mechanism becomes complicated and the production cost also increases.

<Object of the Invention> The present invention has been made in view of the above facts, and an object of the present invention is to automatically operate a pressure contact lever in an operating state and a non-operating state in relation to an operation of mounting and dismounting a copy paper cassette. It is an object of the present invention to provide a paper feed mechanism including a copy paper cassette that can realize a compact structure of the apparatus.

<Summary of the Invention> According to the present invention, the cassette receiving portion defined in the housing of the copying machine, and the opening formed at the front end portion of the bottom wall and the lower portion of the front wall detachably attached to the cassette receiving portion. A cassette main body, a loading plate mounted inside the cassette main body so as to be rotatable about a rear end of the cassette as a fulcrum, a copy paper cassette for storing copy paper, and a front end of the cassette main body through the opening of the cassette main body. A pressure contact lever having an engaging portion at its base, which is selectively positioned between a working condition acting on the plate and a non-acting condition separating from the mounting plate, and urging the pressure contact lever to actuate the working condition. A release lever having a press contact mechanism including a first elastic biasing means and an engaged portion that engages with an engaging portion of the press contact lever at an engaging position, and a tip of the release lever faces the cassette receiving portion. And the engaging portion and the engaging portion that act on the release lever. Second elastic biasing means for urging to engage, and the first elastic biasing means arranged on the front wall of the cassette body and acting on the press contact lever when the copy paper cassette is detached from the cassette receiving portion. An action piece for activating the pressure contact lever to put it in the non-acting state against the biasing force of the means, and the front wall of the cassette body is released when the copy paper cassette is attached to the cassette receiving portion. The release lever is brought into contact with the tip of the lever to operate the release lever from the engagement position against the biasing force of the second elastic biasing means to release the engagement between the engagement portion and the engaged portion. When the pressing lever is brought into the operating state and the pressing piece is operated to the non-operating state by the operating piece when the copying paper cassette is detached from the cassette receiving portion, the release lever is provided with the second elastic biasing means. The engaging portion is returned to the engaging position by the force and Tighten engage an engaging portion, to lock the piezoelectric contact lever in non-activated condition, the sheet feeding mechanism is provided, characterized in that.

<Preferred Specific Example of the Invention> A specific example of the sheet feeding mechanism configured according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, which schematically shows a part of an electrostatic copying machine, the illustrated electrostatic copying machine includes a copying machine housing 2 (a part of which is shown) having a substantially rectangular parallelepiped shape. A rotary drum 4 having a photoconductor on its peripheral surface is rotatably mounted at a substantially central portion of the copying machine housing 2. Around the rotary drum 4, as viewed in the direction of rotation of the rotary drum 4 indicated by arrow 6, a charging corona discharger 8, a developing device 10, a transfer corona discharger 12, and a peeling corona discharger 14 are sequentially provided. A cleaning device including the cleaning blade 16 and the cleaning blade 16 is provided.

In the copying machine housing 2, there is further provided a copying paper transport mechanism 18 for transporting the copying paper through the transfer area (the area between the rotary drum 4 and the transfer corona discharger 12). The copy paper transport mechanism 18 includes a feed roller pair 20, a guide member 22, and a guide plate 2.
4, a pair of transport rollers 26, a pair of guide plates 28, a pair of guide plates 30, and a transport belt mechanism 32, which define a copy sheet transport path for transporting copy sheets.

A paper feed mechanism 34 (described in detail later) constructed according to the present invention is disposed at the upstream end of the copy paper transport path. The paper feed mechanism 34 includes a copy paper cassette 38 that is detachably mounted in a cassette receiving portion 36 defined in the copying machine housing 2 and a feeding roller 40 that is arranged above the cassette receiving portion 36. The roller 40 has a function of sending out the copy sheets stored in the copy sheet cassette 38 one by one. A copy paper double feeding prevention mechanism 42 is provided in association with the feeding roller 40, and the double feeding prevention mechanism 42 is provided.
Serves to reliably convey the copy sheets sent from the copy sheet cassette 38 to the copy sheet conveying path one by one.

The operation of the electrostatic copying machine described above will be summarized.
While being rotated in the direction indicated by arrow 6, the charging corona discharger 8 first performs corona discharge on the photoconductor of the rotary drum 4 to charge the photoconductor to a specific polarity, and then the optical device (not shown). The system causes the image of the original document to be projected onto the photoconductor as indicated by the chain line, thus forming an electrostatic latent image on the photoconductor. Next, the developing device 10 applies a toner image to the electrostatic latent image formed on the photoconductor, so that the electrostatic latent image is converted into a toner image. On the other hand, the copy machine fed from the paper feed mechanism 34 is conveyed to the transfer area in synchronization with the rotation of the rotary drum 4 by the action of the copy paper conveyance mechanism 18. In the transfer area, the above-mentioned copy paper is brought into close contact with the rotary drum 4, and the toner image on the photoconductor is transferred onto the copy paper by the action of the transfer corona discharger 12. The copy paper on which the toner image has been transferred is then peeled from the surface of the photoconductor by the peeling corona discharger 14 and is conveyed toward the conveyance belt mechanism 32 through between the pair of guide plates 30.
The copy sheet is further transported to the downstream side by the transport belt mechanism 32, is subjected to the fixing action of a fixing device (not shown), and is then discharged to a tray (not shown). On the other hand, the rotary drum 4 continues to rotate further, and the residual toner particles remaining on the photoconductor are removed by the action of the cleaning blade 16.

Next, the illustrated paper feed mechanism 34 will be described with reference to FIG. 3 together with FIG. The illustrated paper feed mechanism 34 includes a copy paper cassette 38 which is detachably attached to a cassette receiving portion 36 defined in the copying machine housing 2. In the illustrated electrostatic copying machine, the cassette receiving portion 36 is the copying machine housing 2
A bottom wall 44 of the copying machine housing 2 and a pair of vertical substrates disposed in the copying machine housing 2 at intervals in the front-rear direction (direction perpendicular to the paper surface of FIG. 1). (Not shown), a guide member 48 extending to the right from an opening formed in the left side wall 46 of the copier housing, and a bottom wall 44.
Is defined by the contact portion 52 of the contact member 50 fixed to the right end portion (right end portion in FIG. 1) of the. A feeding roller 40 is arranged above the right end of the cassette receiving portion 36. The feeding roller 40 includes a rotating shaft 54 that is rotatably mounted.
And is rotated in the direction indicated by arrow 56.

On the other hand, the copy paper cassette 38 includes a box-shaped cassette body 58 whose upper surface is open. A loading plate 60 is rotatably mounted in the cassette body 58 with a rear end as a fulcrum, and copy paper is placed on the loading plate 60 as shown in FIGS. 3-A and 3-B. It is placed in a laminated state. A rectangular opening 64 is formed at the front end of the bottom wall 62 of the cassette body 58. In the specific example, one end of the opening 64 extends from the bottom wall 62 of the cassette body 58 to a lower portion of the front wall 66. The copy paper cassette 38 described above is detachably attached to the cassette receiving portion 36 by moving it in the direction shown by an arrow 68 through an opening formed in the left side wall 46 of the copying machine housing 2, while referring to FIGS. It is detached from the cassette receiving portion 36 by moving it in the direction shown by the arrow 70 from the state shown in FIG. 3-B.

In the copier housing 2, the cassette receiving portion 36 is further provided.
A pressure contact mechanism 72 is provided in relation to the. Further explaining with reference to FIG. 2, a support base 74 is fixed to the right end portion of the bottom wall 62 of the copying machine housing 2, and the press contact mechanism 72 is mounted on the support base 74 as required. The pressure contact mechanism 72 includes a substantially L-shaped pressure contact lever 76 whose tip acts on the mounting plate 60 through an opening 64 formed in the cassette body 58. On the other hand, the support base 74 has a pair of mounting brackets 78a and 7a.
8b is provided, and the pressure contact lever 76 is rotatably mounted between the mounting brackets 78a and 78b. In the specific example, one mounting bracket 78a is fixed on the support base 74 by a mounting screw 80, and the other mounting bracket 78b is integrally formed with a part of the support base 74 by bending the pressure contact lever. The protrusions 82a and 82b provided on both sides of the intermediate bent portion of the 76 are attached to the mounting brackets 78a and 7b.
It is rotatably mounted by being inserted into through holes 84a and 84b formed in 8b. Further, a locking concave portion 86 is provided on the base side of the press contact lever 76, and a bent portion 88 provided on the right end portion (the left side portion in FIG. 2 and the right side portion in FIG. 3) of the support base 74. A locking recess 88a is defined, and a coil spring 90 as a first elastic biasing means is interposed between the locking recess 86 and the locking recess 88a. Therefore, the above-mentioned pressure contact lever 76 is elastically biased clockwise in FIGS. 3A and 3B by the action of the coil spring 90.

With respect to the above-mentioned press contact mechanism 72, a lock means 92 for releasably locking the press contact lever 76 in a non-acting state (a state shown in FIG. 3-A) is provided. A lock release mechanism 94 and a lock mechanism 96 are attached. The illustrated locking means 92 includes an engaging projection 98 (which constitutes an engaging portion) provided at an end portion of the pressure contact lever 76 on the base side and an engaged projection 100 (engaged engagement) with which the engaging projection 98 can engage. The engaging projection 98 is the engaged projection 10
When 0 is engaged, the lock state (state shown in FIG. 3-A) is entered. Further, the illustrated lock release mechanism 94 includes an arc-shaped release lever 102, and the release lever 102 is rotatably mounted between a pair of mounting brackets 104a and 104b provided on the support base 74. In the specific example, one mounting bracket 104a is integrally formed with a part of the support base 74 by bending the support base 74, and the other mounting bracket 104b is fixed on the support base 74 by a mounting screw 106, and a release lever. 102 is a protrusion 108 provided on both side surfaces of the base end portion thereof.
By inserting a and 108b into through holes 110a and 110b formed in the mounting brackets 104a and 104b, they are rotatably mounted. On the outer surface side of the release lever 102, a second elastic biasing means composed of a leaf spring 112 is further arranged. The leaf spring 112 is formed in a substantially U shape, and its base side is fixed on the support base 74 by a mounting screw 114. The tip end side of the leaf spring 112 acts on the outer surface of the release lever 102 as shown in FIGS.
In FIG. 3-A and FIG. 3-B, it has the effect of elastically biasing in the counterclockwise direction. In the specific example, the release lever 102 is provided with an engagement protrusion 9 provided on the press contact lever 76.
Corresponding to 8, an engaged protrusion 100 is provided. Therefore, when the locking means 92 is in the locked state, as shown in FIG. 3A, the engaging projection 98 and the engaged projection are in the engaged position.
100 is engaged as required, and the tip end of the engaging projection 98 abuts on the abutted surface 114 defined by the release lever 102, whereby the pressing lever 76 is prevented from turning clockwise, and the abutting projection
The tip end of 100 abuts against the abutted surface 116 defined by the pressure contact lever 76 to prevent the release lever 102 from turning counterclockwise, and thus the locking means 92 is secured by the action of the coil spring 90 and the leaf spring 112. Is held in a locked state. The distal end portion of the release lever 102 is disposed so as to face the cassette receiving portion 36 as shown in the drawing, and is configured to be able to contact the front wall 66 of the cassette body 58. Further, the lock mechanism 96 has an action piece 118 provided on the front surface of the front wall 66 of the cassette body 58. In the specific example, the action piece 118
Are provided at intervals in the width direction of the cassette body 58 (the direction perpendicular to the paper surface in FIGS. 3-A and 3-B) (in FIGS. 3-A and 3-B). Show only one). On the other hand, the above-mentioned action piece is
Corresponding to 118, the contacted portion 120 is provided (in the specific example, the contacted portion 120 is provided at both ends of the pressure contact lever 76). The contacted portion 120 is composed of a triangular contact member 122 provided on the side surface of the press contact lever 76 and a contacted roller 126 rotatably mounted on the side surface via a short shaft 124. The upper surface of the contact member 122 is inclined upward toward the detaching direction of the copying machine cassette 38 indicated by the arrow 70, in other words, the direction in which the contacted roller 126 exists. The abutted member 122 can be omitted when the pressing lever 76 can be swung as required by the action of the action piece 118 as described later. Further, although the working piece 118 and the contacted portion 120 are two in the specific example,
As will be described later, if the press contact lever 76 can be turned as required, either one can be omitted. Further, as shown in a specific example, it is preferable to provide a guide member 128 on the side opposite to the side where the contacted member 122 is present, in association with each of the contacted rollers 126. Guide member 128
Has a triangular shape, and the upper surface thereof is inclined upward toward the mounting direction of the copy paper cassette 38 indicated by the arrow 68, in other words, the direction in which the contacted roller 126 exists.

Further, in the specific example, as shown in FIGS. 3-A and 3-B, the contact member 50 is a contact portion that extends substantially vertically upward.
52 (defining a part of the cassette receiving portion 36 as described above) and an inclined portion 130 extending obliquely upward from the upper end of the contact portion 52 toward the copy paper conveyance direction, and above the support base 74. Covering. That is, in the specific example, most of the press contact mechanism 72 and the lock release mechanism 94 are accommodated in the space defined by the support base 74 and the contact member 50, and the tip end side of the press contact lever 76 and the tip end portion of the release lever 102. However, the contact portion 5 of the contact member 50
It projects into the cassette receiving portion 36 through an opening 132 formed at a substantially central portion in the second lateral direction (direction perpendicular to the paper surface in FIGS. 3-A and 3-B). Also, the feeding roller
A copy paper double feed prevention mechanism 42 is provided in association with 40, and the illustrated double feed prevention mechanism 42 includes a friction member 134 (a member having a relatively high coefficient of friction) that acts on the peripheral surface of the feeding roller 40. The friction member 134 is fixed to the upper surface of the inclined portion 130 of the contact member 50. Furthermore, a rectangular accommodating recess 136 is formed on the upper surface of the right end portion of the bottom wall 44 of the copying machine housing 2 that defines a part of the cassette receiving portion 36. In the accommodation recess 136,
As shown in FIG. 3-A, when the pressure contact mechanism 72 is in the non-acting state, the front end side of the pressure contact lever 76 is accommodated as required, whereby the front end portion of the pressure contact lever 76 is placed on the mounting plate 60 in the cassette body 58. The copy paper cassette 38 can be detached from the cassette receiving portion 36.

Next, the operation and effect of the paper feed mechanism 34 having the above-described configuration will be described.
A description will be given mainly with reference to FIGS. 3-A and 3-B.

When the copy paper cassette 38 is detachably attached to the cassette receiving portion 36, the press contact mechanism 72, and hence the press contact lever 76, is moved to the 3-A position.
It is held in the inactive state shown in the figure (holding in the inactive state is automatically achieved by simply detaching the copy paper cassette 38 from the cassette receiving portion 36, as described later). In this state, the copy paper cassette 38
Is inserted into the cassette receiving portion 36 through the opening formed in the left side wall 46 of the copying machine housing 2 and moved in the mounting direction of the copying paper cassette 38 indicated by the arrow 68 (see also FIG. 1). The lower ends of the pair of action pieces 118 provided on the front wall 66 of the cassette body 58 are brought into contact with the upper surface of the corresponding guide member 128 and moved along the upper surface, so that the contacted portion 120,
Therefore, it is moved as required over the abutted roller 126 and the abutted member 122 (while the action piece 118 is moved along the upper surface of the guide member 128 as understood from FIG. 3-A). , The front side of the copy paper cassette 38 is moved slightly upward with the movement thereof, and the front side of the copy paper cassette 38 is moved while the action piece 118 is moved along the upper surface of the abutted member 122. Will be moved somewhat downward). Next, when the copy paper cassette 38 is further moved in the direction indicated by the arrow 68, immediately before the copy paper cassette 38 is mounted in the cassette receiving portion 36 as required, in other words, the front wall 66 of the cassette body 58 is brought into contact with the contact member 50.
The front wall 66 comes into contact with the tip of the release lever 102 immediately before it comes into contact with the contact portion 52, and the release lever 102 moves with the elastic biasing force of the leaf spring 112 as the copy paper cassette 38 moves in the direction shown by the arrow 38. Against the above, it is swung clockwise from the engagement position shown in FIG. Then, as shown in FIG. 3-B, the copy paper cassette 38 is mounted on the cassette receiving portion 36 as required (in other words, the front wall 66 of the copy paper cassette 38 is abutting member in the mounting direction indicated by the arrow 68). When the release lever 102 pivots counterclockwise, the lock means 92 is locked, in other words, the engagement protrusion 98 provided on the press contact lever 76 and the release lever 102 are moved. The engaged state of the provided projection 100 to be engaged is released. As a result, the pressure contact lever 76 can be swung, swung clockwise by the action of the coil spring 90 in FIG. 3A, and the front end of the press contact lever 76 is accommodated in the cassette body 58. The mounting plate 60 is swung counterclockwise in FIG. 3-A with the rear end as a fulcrum. Thus, the pressure contact mechanism 72, and thus the pressure contact lever 76, is
The uppermost copy sheet of the stacked copy sheets P placed on the mounting plate 60 in the operating state shown in FIG. 7B is elastically biased by the coil spring 90, and the pressing lever is elastically biased.
By the action of 76, the peripheral surface of the feeding roller 40 is pressed as required (therefore, the copying paper can be fed, and the feeding roller 40 is rotated in the direction shown by the arrow 56, so that The copy paper is delivered from the copy paper cassette 38 as desired). In addition, in a specific example, FIG.
As shown in FIG. 6B, the upper end of the front wall 66 of the cassette body 58 is cut out as required to enable the above-described mounting of the copy paper cassette 38 and the feeding of copy paper from the copy paper cassette 38. .

In the above-mentioned mounted state of the copy paper cassette 38, the uppermost copy paper is pressed against the peripheral surface of the feeding roller 40 with a required pressure by the action of the press contact mechanism 72, whereby the copy paper cassette 38 is mounted at the mounting position (first position). 3-B) (position shown in FIG. 3-B), it is preferable to have the following structure in order to hold the copy paper cassette 38 in the mounting position more reliably. That is, a recess is provided at a required position on the bottom wall 44 of the copying machine housing 2 that defines a part of the cassette receiving portion 36, and a projection to be accommodated in the recess is provided on the lower surface of the bottom wall 62 of the cassette main body 58. When the paper cassette 38 is mounted on the cassette receiving portion 36 as described above, it is preferable that the projection of the cassette body 58 is received in the recess formed in the bottom wall 44 as required. With such a configuration, even if the copy paper cassette 38 is simply moved in the mounted state in the direction shown by the arrow 70, the movement of the copy paper cassette 38 is surely prevented by the action of the concave portion and the projection, and the copy paper cassette 38 is placed in the mounting position. Be held securely in the
The recess is engaged with the projection by lifting the rear end side 38 a little upward, and in this state, the copy paper cassette 38 is moved in the direction shown by the arrow 70 to be removed from the cassette receiving portion 36. be able to).

Then, the copy paper cassette 38 mounted as described above.
When the copy paper cassette 38 is moved in the removal direction indicated by the arrow 70 in FIG. 3-B, the copy paper cassette 38 is moved in the arrow 70 of the copy paper cassette 38 at the initial stage of the above movement. The release lever 102 is turned counterclockwise in FIG. 3-B with the movement in the direction shown. In the specific example, since the release lever 102 is elastically biased counterclockwise by the action of the leaf spring 112, the release lever 102 pivots with its tip abutting the front wall 66 of the cassette body 58. To be done. Then
When the copy paper cassette 38 is further moved in the direction shown by the arrow 70, the front wall 66 of the cassette body 58 is separated from the release lever 102 (thus, the release lever 102 is held in a lockable state not shown). ), Then cassette body 58
Each of the action pieces 118 provided on the abutting portion abuts on the abutted portions 120 provided on both side ends of the press contact lever 76 and acts on them. The action piece 118 acts on the contacted portion 120, in the specific example, first acting on the upper surface of the contacted member 122 and then on the peripheral surface of the contacted roller 126, as indicated by the arrow 70 of the copy paper cassette 38. The pressure contact lever 76 is rotated counterclockwise in FIG. 3B against the elastic biasing force of the coil spring 90 as the direction moves. On the other hand, at the end of such turning of the press contact lever 76, the engagement protrusion 98 provided on the press contact lever 76 causes the release lever to move.
By acting on the arc-shaped inner surface of 102 and turning it slightly to the clockwise direction in FIG. 3-A against the elastic biasing force of the leaf spring 112, the engaged projection 100 provided on the release lever 102 is surmounted. . Then, as shown in FIG.
Move 38 in the direction indicated by arrow 70 (in other words,
When the copy paper cassette 38 is moved to the position shown in FIG. 3-A in the direction shown by the arrow 70), the engaging protrusion 98 and the release lever provided on the press contact lever 76 at the engaging position shown in FIG. 3-A. The engaged projection 100 provided on the 102 is engaged as required, and the engaged state is maintained by the action of the coil spring 90 and the leaf spring 112. In the engaged state, the tip end of the pressure contact lever 76 is accommodated in the accommodation recess 136 formed in the bottom wall 44 and is separated from the mounting plate 60 in the cassette body 58,
The pressure contact mechanism 72, and thus the pressure contact lever 76, is held in the non-acting state, and the copy paper cassette 38 can be mounted as described above. In order to remove the copy paper cassette 38 from the cassette receiving portion 36, the copying paper cassette 38 may be moved further from the state shown in FIG. 3-A in the detaching direction shown by the arrow 70 (FIG. 3-B).

As described above, in the above-described paper feed mechanism 34, the press contact mechanism 72 is automatically held in the above-mentioned operating state by detachably mounting the copy paper cassette 38 in the cassette receiving portion 36 as required (therefore, the paper feeding mechanism 34 is supplied). When the copy paper cassette 38 is detached, the press contact mechanism 72 is automatically held in the non-acting state by moving the copy paper cassette 38 in the detaching direction. It becomes possible to remove the paper cassette 38 and also install a new copy paper cassette).

Although one specific example of the paper feed mechanism configured according to the present invention has been described above, the present invention is not limited to this specific example, and various modifications and corrections can be made without departing from the scope of the present invention. Is.

<Effect of the Invention> The copy paper cassette including the copy paper cassette according to the present invention is configured as described above, and the front wall of the cassette body contacts the tip of the release lever when the copy paper cassette is mounted on the cassette receiving portion. The release lever is actuated from the engagement position against the urging force of the second elastic biasing means to release the engagement between the engaging portion and the engaged portion to bring the pressure contact lever into the operating state, and copy. When the pressing lever is actuated to the non-acting state by the action piece when the paper cassette is detached from the cassette receiving portion, the release lever is returned to the engaging position by the urging force of the second elastic biasing means and the engaging portion. And the engaged portion,
Since the pressure lever is locked in the inactive state,
The pressing lever can be automatically operated in the operating state and the non-operating state in association with the operation of mounting and dismounting the copy paper cassette. Further, according to the present invention, the opening formed in the cassette body is provided in the front end portion of the bottom wall and the lower portion of the front wall,
Since the action piece for activating the pressure contact lever for activating the inside of the opening is arranged on the front wall of the cassette main body, it is possible to configure each of these members so that there is almost no protrusion particularly downward from the cassette receiving portion, and the entire apparatus is constructed. It can be made compact.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing a part of an electrostatic copying machine including a specific example of a sheet feeding mechanism configured according to the present invention. FIG. 2 is an enlarged perspective view showing the pressure contact mechanism of the paper feed mechanism of FIG. 1 and members related thereto in an exploded manner. 3A and 3B are enlarged cross-sectional views showing a state when the pressure contact mechanism is in a non-operating state and a state when the pressure contact mechanism is in the operating state, respectively. 2 …… Copier housing 34 …… Paper feed mechanism 36 …… Cassette receiving part 38 …… Copy paper cassette 58 …… Cassette body 60 …… Loading plate 62 …… Bottom wall 64 …… Opening 72 …… Pressure contact mechanism 76 ...... Pressing lever 92 …… Locking means 94 …… Unlocking mechanism 96 …… Locking mechanism

Claims (2)

[Claims] 1. A cassette receiving portion defined in a housing of a copying machine, a cassette body detachably attached to the cassette receiving portion and having a front end portion of a bottom wall and an opening formed in a lower portion of the front wall, and the cassette. A copy sheet cassette, which is mounted in the main body so as to be rotatable about its rear end as a fulcrum, accommodates copy sheets, and an operating state in which the front end acts on the copy sheet plate through the opening of the cassette body. And a pressure contact lever that is selectively positioned in a non-acting state to be separated from the mounting plate and has an engaging portion at its base, and a first elastic biasing means for urging the pressure contact lever to operate in the acting state. And a release lever having a tip end facing the cassette receiving portion, the release lever having an engaged portion engaging with an engaging portion of the pressure contact lever at an engaging position, And urges the engaged portion and the engaging portion to engage with each other. Second elastic biasing means, which is disposed on the front wall of the cassette body, acts on the pressing lever when the copy paper cassette is detached from the cassette receiving portion, and resists the biasing force of the first elastic biasing means. And an operating piece for activating the press contact lever to bring it into the non-acting state, and the front wall of the cassette main body comes into contact with the tip of the release lever when the copy paper cassette is attached to the cassette receiving portion. The release lever is operated from the engagement position against the urging force of the second elastic biasing means to release the engagement between the engagement portion and the engaged portion to bring the pressure contact lever into the operating state. , The release lever is moved to the engagement position by the urging force of the second elastic biasing means when the pressing lever is operated in a non-acting state by the action piece when the copy paper cassette is detached from the cassette receiving portion. The engaging portion and the engaged portion are engaged by being returned. Because, to lock the piezoelectric contact lever in non-operative position, wherein the paper feed mechanism. 2. A paper feed mechanism including a copy paper cassette according to claim 1, wherein the pressure contact lever includes a contacted roller on which the action piece operates.