Paper feed tray

Information

  • Patent Grant
  • 6634638
  • Patent Number
    6,634,638
  • Date Filed
    Tuesday, December 4, 2001
    23 years ago
  • Date Issued
    Tuesday, October 21, 2003
    21 years ago
Abstract
All the constituent members of a tray 1, for example, a side guide 30, a paper separating claw 50, a tray body 10, a drawing handle member 70, a member for regulating an end guide 40, and a holding member for holding a retard roll 60 each have a snap-fit structure. Therefore, the assembling and disassembling of the tray can be easily performed. The tray is formed only from members that enable all the steps of processes of assembling and disassembling the tray to be performed from the same direction without changing the orientation of the tray.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a structure of a paper feed tray for use in an image forming apparatus, such as a printer, a copying machine, a facsimile machine, and a composite machine thereof.




2. Description of the Related Art




A paper feed tray of an image forming apparatus comprises components, such as a casing, a paper loading plate provided on the bottom portion of the casing for loading paper thereon, a side guide for regulating a side portion of a sheet of paper, an end guide for determining a position of a tail edge of a sheet of paper, a paper separating claw for separating paper sheet by sheet, a retard roll, and a casing attaching/detaching handle. Trays each enabled to accommodate 250 sheets of paper (that is, a half pack) or more need to ensure sufficient stiffness thereof. Further, there is necessity for assembling each of components into the tray with good accuracy so that sheet conveying performance is maintained even when a sheet conveying speed is increased to a high value. Therefore, a paper feed tray according to the related art necessarily has a structure in which many screws are tightened. This results in complex assembling and increase in cost of the tray. Moreover, when being conscious of recycling of the tray, disassembling thereof requires a great deal of labor in case that there are many places, to each of which a screw is fastened, in the tray. Simultaneously, it takes time and labor to sort out individual members thereof into a group of members to be recycled and another group of members to be scrapped.




Furthermore, generally, the greater part of the paper feed tray is made of a resin so as to reduce the cost and weight thereof. When being conscious of reuse of each of components of the paper feed tray, it is necessary to disassemble the paper feed tray without damaging the components made of a resin. When screws are fastened to the components made of a resin, screw holes are damaged during the disassembling of the paper feed tray. Thus, it is difficult to reassemble the paper feed tray by using the same screw holes.




SUMMARY OF THE INVENTION




In view of such circumstances, an object of the invention is to substantially improve the structure of a paper feed tray for use in an image forming apparatus and to provide a paper feed tray that is easily assembled and disassembled and that is rational in relation recycling, reuse, and disposal.




The invention is accomplished to solve the aforementioned problems. According to a first aspect of the invention, there is provided a paper feed tray comprising a casing, a paper loading plate for loading paper thereon, the paper loading plate provided on a bottom portion of the casing, a side guide for regulating a side portion of a sheet of paper, an end guide for determining a position of a tail edge of a sheet of paper, a paper separating member for separating paper sheet by sheet, a casing attaching/detaching handle, an operation tab for operating the side guide, and a catching portion for catching the paper separating member, the catching portion formed between the side guide and the operation tab. In this case, it is preferable that the paper separating member is a paper separating claw and a fulcrum of the paper feed claw is formed to be integral with a shaft for fitting the operation tab into the side guide. Further, it is preferable that a snap is disposed so that a force received by the paper separating claw from paper during supply of paper acts in a direction in which snap-fitting performed on the operation tab to be utilized at assembling of the tray does not become off. Furthermore, a paper feed tray of the invention may have a structure which includes a slit portion that elastically opens and tentatively holds a paper separating claw in a retreat position and is formed between an operation tab member and a side guide as means for avoiding a paper separating claw serving as a hindrance to assembling of a paper loading plate. The invention provides a paper feed tray having a structure that comprises a regulating member for regulating a movable range of the paper separating claw so as to satisfy paper feed performance. In this tray, this regulating member has a structure adapted to bend owing to the elasticity thereof. Further, when assembling the tray, the regulating member bends in such a way as to prevent the paper separating claw from interfering with another member to avoid the paper separating claw. At that time, the paper separating claw and the regulating member may be placed so that even when the regulating member for regulating the movable range of the paper separating claw is bent by a force, which is received by the regulating member during the supply of paper, the separating claw is firmly regulated in a direction in which the separating claw is prevented from escaping from a normal position thereof to be regulated.




Further, according to a second aspect of the invention, there is provided a paper feed tray comprising a tray body, a drawer handle member provided on the tray body, for attaching/detaching the tray body to/from an image forming apparatus, the drawer handle member constituting a part of an exterior cover of the image forming apparatus, and a fixing member having an elastic piece and an engaged portion, wherein the elastic piece is elastically deformable, has an engaging portion, and is provided on one of the tray body and the drawer handle member, the engaged portion and is provided on the other thereof, the tray body and the drawer handle member comprise at least two constituent members, the engaging portion and the engaged portion is engaged with each other to fix the tray body and the drawer handle member to each other. At that time, it is preferable that the fixing member consists of the elastic piece and the engaged portion. Further, it is preferable that when the tray body is attached to and detached from the image forming apparatus, a direction of a force applied to the fixing member is different from a direction in which the engaging portion is engaged with the engaged portion. Moreover, it is preferable that when the tray body is lifted by holding the drawer handle member, a direction of a force applied to the fixing member is different from a direction in which the engaging portion is engaged with the engaged portion. Furthermore, a direction in which the engaging portion is engaged with the engaged portion may be substantially perpendicular to a direction in which the tray body is attached to and detached from the image forming apparatus. Further, it is preferable that the tray body and the drawer handle member are made of different synthetic resins and the synthetic resin constituting the tray body is a more durable material than that constituting the drawer handle member. Moreover, it is preferable that the paper feed tray further comprises a pair of plate-like arm members provided at both end portions of the drawer handle member, respectively, the plate-like members extended in a direction in which the tray body is attached to and detached from the image forming apparatus, wherein a force received from the tray body is applied to each of the arm members in a direction perpendicular to a direction of thickness thereof. Furthermore, wherein each of the arm members may be provided to abut against a wall surface that is provided on a sidewall of the tray body and extends in a direction substantially perpendicular to the direction in which the tray body is attached to and detached from the image forming apparatus. Incidentally, it is preferable that a space is provided adjacent to the elastic piece. Preferably, the space is a concave portion provided in the sidewall of the tray body.




Further, according to a third aspect of the invention, there is provided A paper feed tray comprising a tray body, a drawer handle member provided on the tray body, for attaching/detaching the tray body to/from an image forming apparatus and, the drawer handle member constituting a part of an exterior cover of the image forming apparatus, a fixing member for fixing the tray body and the drawer handle member to each other, provided on one of the tray body and the handle drawer member, an arm member having a plate-like shape, being elastically deformable, and extending in a direction in which the tray body is attached to and detached from the image forming apparatus, a fixing portion for positioning and fixing the arm member, provided on the other thereof. In this case, it is preferable that the arm member is provided to be parallel to a sidewall of the tray body and the fixing portion abuts against a plate-thickness surface of the arm member to position and fix the arm member. Further, it is preferable that the arm member is elastically deformable in a direction substantially perpendicular to a direction in which the tray body is attached to and detached from the image forming apparatus.




Next, the invention provides another paper feed tray, which comprises a regulating member, provided in an end guide enabled to correspond to a plurality of paper lengths and to easily move, for holding a base of the end guide and for regulating a moving operation in such a way as to prevent the end guide from slipping off. In this tray, the regulating member is a member adapted to have elasticity in itself. In this tray, the regulating member for holding the base of the end guide and for regulating a moving operation in such a way as to prevent the end guide from slipping off may be a member adapted to be bent when attached to and detached, and to enable the end guide to easily move without detaching the end guide.




It is preferable that the elastic member having elasticity is a resin sheet member. Further, a regulating member, which is provided in an end guide enabled to correspond to a plurality of paper lengths and to easily move, for holding the base of the end guide and for regulating a moving operation in such a way as to prevent the end guide from slipping off, may be a member to be assembled from assembly members each having elasticity so as to easily assemble the tray by utilizing the elasticity without a tool.




Another paper feed tray is preferable, in which the members each serving as the assembly member and having elasticity in itself are easily assembled into the regulating member without a tool by utilizing the elasticity, and has a part to be bent when assembled, and another part to be bent when operated by a user, and in which the part to be bent when assembled, and the part to be bent when operated by a user are formed separately from each other.




Another preferable paper feed tray may have a structure in which a projection portion, provided on a retard roll holding member, for regulating an own position, and an attachment-side positioning member having elasticity. When the tray is assembled, the attachment-side positioning member is pushed up by the projection portion provided on the retard roll holding member for regulating the position, so that the positioning member is enabled to move to a normal position.




As described above, according to the invention, all the attaching members for attaching constituent members of the tray to one another have a snap-fit structure to thereby enable easy assembling and disassembling thereof. Further, the paper feed tray is constituted only by members that enable all steps of processes of assembling and disassembling the tray to be performed from the same direction without changing orientation of the tray. Consequently, the invention contributes to reduced labor and cost.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a plan view illustrating a paper separating claw, a side guide, and an operation tab.





FIG. 2

is a side view illustrating the side guide.





FIG. 3

is a plan view illustrating the paper separating claw.





FIG. 4

is a side view illustrating the paper separating claw.





FIG. 5

is a side view illustrating the operation tab.





FIG. 6

is a rear view illustrating the operation tab.





FIG. 7

is a side view illustrating another operation tab.





FIG. 8

is a sectional view taken in a direction of arrows along line A—A of FIG.


5


.





FIG. 9

is a sectional view taken in a direction of arrows along line B—B of FIG.


5


.





FIG. 10

is a sectional view taken in a direction of arrows along line C—C of FIG.


7


.





FIG. 11

is a sectional view taken in a direction of arrows along line D—D of FIG.


7


.





FIG. 12

is a side view illustrating a retreating state of the paper separating claw.





FIG. 13

is a side view illustrating a mounting state of the paper separating claw.





FIG. 14

is a side view illustrating a handle attaching portion.





FIG. 15

is a perspective view illustrating a state in which the handle attaching portion is not assembled yet.





FIG. 16

is a sectional view in a direction of arrows along line E—E of FIG.


14


.





FIG. 17

is a plan view illustrating members of the handle attaching portion.





FIG. 18

is a plan view illustrating an end guide.





FIG. 19

is a bottom view illustrating the end guide.





FIG. 20

is a side view illustrating the end guide.





FIG. 21

is a rear view illustrating the end guide.





FIGS. 22A and 22B

are a plan view of a resin member and a side view thereof, respectively.





FIG. 23

is a plan view illustrating an end guide mounting portion.





FIG. 24

is a plan view illustrating a retard member mounting process.





FIG. 25

is a plan view illustrating the entire paper feed tray.





FIG. 26

is a side view illustrating the entire paper feed tray.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Hereinafter, an embodiment of the invention is described with reference to the accompanying drawings.

FIG. 25

illustrates a plan view of a paper feed tray


1


.

FIG. 26

illustrates a side view thereof. A paper feed tray


1


has a casing


10


, a paper loading plate


20


, a side guide


30


, an end guide


40


, a paper separating claw


50


, a retard roll


60


, and a casing inserting/removing handle


70


. The casing


10


is a box-like one for the paper feed tray


1


, comprises a base plate and sidewall plates that surround periphery of the casing


10


, and is opened in the top surface thereof. The paper loading plate


20


is a plate-like tray to be disposed on the base plate of the casing


10


, provided with an ascending gradient in a direction in which paper travels, and has an elevating function of going up and down according to an amount of paper. The side guide


30


regulates both sides of paper contained in the paper feed tray


1


to guide the paper by holding the paper at a central portion in a direction of width thereof. Further, the side guide


30


has walls erected and provided at the left-hand side and the right-hand side thereof, respectively. An operation tab is mounted on each of the erected walls so that distance between the erected walls can be adjusted to the width of paper according to the paper size. The end guide


40


is a member for positioning the tail edge of the paper and adapted to be moved to a certain position according to the length of the paper to be set at such a position. The paper separating claw


50


is an oscillating member that has claws provided at both sides of an end in a direction in which paper is fed and that handles sheets of paper to separate the paper sheet by sheet and to send out the separated sheet of paper. This paper separating claw


50


is attached to the side guide


30


or is movable in the direction of width of paper together with the side guide


30


. The retard roll


60


is a roll provided at a central portion of a paper output end for permitting the paper to smoothly travel in a direction in which the paper is sent out and provided on the base plate of the casing. The casing inserting/removing handle


70


is a handle provided at the loading side rear end of the casing


10


for inserting/removing the entire paper feed tray


1


into/from a printer body.





FIG. 1

is a plan view illustrating the side guide


30


and the paper separating claw


50


according to the embodiment of the invention.

FIG. 2

is a side view illustrating the side guide


30


. According to the invention, the paper feed tray is configured so that the paper separating claw


50


is caught between a side plate


31


of the side guide


30


and an operation tab


35


. Thus, the member configuration of the paper feed tray is simplified. In the paper feed tray according to the invention, a catching portion is formed. When the catching portion is attached to an operation tab attaching hole


33


provided in the sidewall


31


of the paper side guide


30


, the catching portion catches the paper separating claw


50


together with the operation tab


35


. The paper separating claw


50


has a nail


51


for holding an edge of paper and swings around a fulcrum


52


in a direction in which the claw goes up and down, as illustrated in a plan view thereof shown in FIG.


3


and in a side view thereof shown in FIG.


4


. The paper separating claw


50


also has an oscillation regulating portion


53


. According to the invention, regarding the fulcrum of the paper separating claw


50


is formed to be integrated with a shaft of the operation tab


35


to be fitted into the sidewall


31


of the side guide


30


. Consequently, this enables simultaneous attachment of the paper separating claw


50


and the operation tab


35


to the side guide


30


during an assembling operation of attaching the paper separating law


50


thereto.





FIG. 5

illustrates a side view of an example of the operation tab


35


.

FIG. 6

illustrates a rear view of FIG.


5


.

FIG. 7

illustrates a side view of another example of the operation tab


35


. The shaft


36


to be fitted into the side guide


30


shown in

FIGS. 5

to


7


is made to coincide with an oscillation center hole


52


. To facilitate the attachment of the shaft


36


, a U-shaped cutout is formed in a wall of this part of the operation tab


35


to form a flexible portion


37


. The example shown in

FIG. 5

differs from that shown in

FIG. 7

in a direction in which the cutout of this flexible portion


37


is formed. Further, a snap


38


for nipping the oscillation regulating portion


53


of the paper separating claw


50


is provided.




The paper separating claw


50


is snap-fitted into the snap


38


provided in the operation tab


35


. This snap


38


sets the paper separating claw


50


so that a force received by the paper separating claw


50


from paper during supply of the paper acts in a direction in which the snap-fitting of the paper separating claw


50


into the snap


38


to be utilized at the assembling of the tray is not off. During the supply of paper, the paper separating claw


50


undergoes pressure exerted thereon by the paper from below. This pressure is concentrated on the shaft


36


of the paper separating claw


50


. According to the invention, the snap


38


is disposed so that when a force is applied onto the shaft, the force acts in a direction in which the snap-fitting to be made to function during the assembling of the tray is not off. This is concretely described hereinbelow.





FIG. 8

illustrates a sectional view taken in a direction of arrows along line A—A of FIG.


5


.

FIG. 9

illustrates a sectional view taken in a direction of arrows along line B—B of FIG.


5


. As shown in

FIG. 8

, the shaft


36


is a shaft that attaches the operation tab


35


to the sidewall


31


of the side guide


30


and supports the oscillation center hole


52


of the paper separating claw


50


. When a load


54


exerted by the paper separating claw


50


upwardly acts on the shaft


36


from below, a clockwise moment acts on the shaft


36


as indicated by an arrow


55


shown in

FIG. 8

, because of the U-shaped cutout formed in the wall of the shaft attaching portion to be opened in the lower part thereof. Thus, the shaft


36


shown in

FIG. 9

tends to bend in a direction in which the flexible portion


37


opens and the claw


50


slips off. At that time, a lower part of the snap


38


tends to swing clockwise around an upper part thereof serving as a fulcrum. Therefore, the shaft


36


tends to bend in a direction in which a stopper claw


39


comes off.





FIG. 10

shows a sectional view taken in a direction of arrows along line C—C of FIG.


7


.

FIG. 11

is a sectional view taken in a direction of arrows along line D—D of FIG.


7


. In this case, when a counterclockwise moment indicated by the arrow


55


is applied thereto, the moment acts in a direction in which the shaft


36


cuts into the side plate of the side guide. Furthermore, in

FIG. 11

, a counterclockwise moment is applied thereto so that the snap


38


swings counterclockwise around the fulcrum as indicated by an arrow


57


. Thus, the snap


38


bends in a direction in which the stopper claw


39


digs thereinto. Therefore, the operation tab


35


having the shape shown in

FIGS. 10 and 11

is more preferable than that having the shape shown in

FIGS. 8 and 9

.




When the paper loading plate


20


is assembled, a paper separating claw


50


is an hindrance to the assembling thereof. As illustrated in

FIGS. 1 and 2

, a projection


32


is provided on a part of the sidewall


31


of the side guide


30


as means for avoiding this hindrance so as to be able to tentatively catch and hold the paper separating claw


50


between the side guide


30


and the operation tab


35


by utilizing the elasticity of the operation tab


35


. That is, to avoid the paper separating claw


50


serving as a hindrance to the assembling of the paper loading plate


20


and to fix the paper separating claw


50


to a temporary avoidance position, a narrow slit portion is provided between the operation tab


35


and the sidewall


31


of the side guide. As illustrated in

FIG. 12

, when the paper separating claw


50


is swung, the slit between the projection


32


and the operation tab


35


is slightly widened by the elasticity of the operation tab


35


. Then, the paper separating claw


50


is caught between the sidewall


31


of the side guide


30


and the operation tab


35


so that the oscillating position of the paper separating claw


50


can be retained. This mechanism portion can be effectively utilized when the paper separating claw is assembled.




In order to satisfy the paper feed performance, a member for regulating a moveable range of the paper separating claw


50


is provided in a tail portion of the paper separating claw


50


, as shown in FIG.


13


. This regulating member


38


is formed in the operation tab


35


to have a claw structure member and to bend owing to elasticity thereof. The paper separating claw


50


and the regulating member


38


are disposed so that when the regulating member


38


for regulating the movable range of the paper separating claw


50


is bent by force, which this member undergoes during the paper is supplied, in a direction in which the force is prevented from escaping. When the paper separating claw


50


is assembled, the claw


50


has a structure, for example, a snap-fit structure, in which the regulating member


38


bends so that the paper separating claw


50


can avoid so as not to interfere with other members. The regulating member


38


has a shape and structure of a claw, which allow the regulating member


38


to bend when a force is applied thereto during the supply of paper to prevent the paper separating claw


50


from escaping.




Next, a structure for attachment between a paper feed tray body (that is, the casing


10


) and a drawer handle member


70


provided in front of the paper feed tray is described hereinbelow.

FIG. 14

is a side view illustrating an attaching portion where the drawer handle member


70


is attached to the tray body


10


according to the embodiment of the invention.

FIG. 15

is a perspective view illustrating a state in which the handle attaching portion is not assembled yet.

FIG. 16

is a sectional view taken in a direction of arrows along line E—E of FIG.


14


.

FIG. 17

is a sectional view taken in a direction of arrows along line F—F of FIG.


14


. The drawer handle member


70


attaches/detaches the traybody


10


to/from an image forming apparatus and constitutes a part of an exterior cover of the image forming apparatus. The tray body


10


and the drawer handle member


70


are constituted by different members, respectively. A member for fixing each of the tray body


10


and the drawer handle member


70


comprises an elastic piece, which has an engaging portion and can elastically deform, and an engaged portion with which this engaging portion is engaged. With such a configuration, even when variation in design of the exterior cover occurs, the variation in design thereof can be coped with by changing only the drawer handle portion. Thus, the image forming apparatus can be used without changing the tray body thereof. Moreover, even when models of image forming apparatus differ in exterior cover from one another, the tray body is designed to be used in common thereamong so that the tray body can be reused among such models of the image forming apparatus. Furthermore, all the members of the tray can be reused. A plate-like elastically deformable arm member


71


is extended in a direction where the tray body


10


is attached to and detached from the image forming apparatus. The drawer handle member


70


is fixed to a positioning stationary portion provided in the tray body


10


.




As illustrated in

FIG. 15

, the drawer handle member


70


is attached to the tray body


10


by being pushed into a side portion of the body


10


in an insertion direction indicated by an arrow


82


. The drawer handle member


70


has the side-plate-like arm member


71


. The arm member


71


is inserted into and firmly fixed to a concave portion formed of upper and lower flanges


11


and


12


and a wall


13


provided on a side plate of the tray body


10


. A load and a bending moment applied to the drawer handle member


70


are born by the top and bottom surfaces


74


,


75


of the arm member


71


, which abut against the upper and lower flanges


11


and


12


of the tray body


10


and the front end surface of the member


71


, which abuts against the wall


13


of the tray body


10


. The member


70


is adapted so that a component in a direction


80


(see

FIG. 14

) of a force exerted by the tray body


10


is supported in a direction perpendicular to the thickness of the arm member


71


. Thus, the arm member


71


can withstand impacts, which are caused by holding, attaching and detaching a heavy paper feed tray, by using a simple structure. Moreover, the arm member


71


is provided to abut against the wall


13


provided on the sidewall of the tray body so as to be nearly perpendicular to a direction in which the tray is attached to and detached from the apparatus. Thus, the arm member


71


can hold the weight of the tray by using a space equal to that of the tray according to the related art. Further, the arm member


71


can withstand impacts that are caused by attaching the tray to and detaching the tray from the apparatus.




The tray body


10


has a positioning projection (that is, the engaging portion)


72


. The arm member


71


has a hole (that is, the engaged portion)


73


into which this projection


72


is fitted. Further, the arm member


71


has snaps


76


, which are snap-fitted into the tray body


10


, at the top and bottom parts of a tray-side end portion. Each of these snaps


76


is a rectangular elastic piece and has a projection


78


to be fitted into a hole


79


provided in a corresponding one of the flanges


11


and


12


of the tray body


10


, as shown in

FIGS. 14

,


15


, and


16


. The projection


78


of each of the snaps


76


is elastically fitted thereinto in a direction of an arrow


77


(that is, in a direction in which engaging with each other), as shown in FIG.


16


. This direction is perpendicular to the direction


80


of the force applied to the handle member


70


. Thus, the snap-fitting does not become off owing to a load imposed on the handle member


70


. Accordingly, detachment between the engaging portion and the engaged portion can be more reliably prevented by the simple structure. Incidentally, in case that the tray body


10


and the handle member


70


are formed from different synthetic resins, respectively and the synthetic resin used for forming the tray body


10


is a durable material, the tray body


10


is hard to be worn down and damaged. Thus, when the design of the tray is changed and/or the tray is reused, the reuse thereof can be performed a plurality of times.




When the tray body


10


is lifted by using the drawer handle member


70


, a large twisting force is generated in each of the tray body


10


and the handle member


70


. This twisting force is concentrated in a stationary part of each of the tray body


10


and the handle member


70


. Thus, according to the invention, a direction, in which the force is applied, is set to be different from the direction, in which the snap-fitting is off and to be oriented about 90 degrees away therefrom. Further, the arm member


71


undergoing the force at the side of the handle member


70


is formed so that the force is applied thereto in a direction perpendicular to the thickness of the arm member


71


. Furthermore, the structure is adapted so that the arm member


71


is held with the upper flange


11


and the lower flange


12


of the tray body


10


. Consequently, even when screw fastening is not used, the disengagement of a snap claw is not caused by the large twisting force applied between the tray body


10


and the handle member


70


. Moreover, spaces, such as the cutout and the concave portion


81


, are provided adjacent to the snap


76


that is an elastic piece of the stationary member. In case that the drawer handle member


70


is disassembled from the tray body


10


, the snap


76


can be elastically deformed through the space provided adjacent to the snap


76


serving as the elastic piece. The engaging portion and the engaged portion can easily be detached from each other.




Next, the improvement of the end guide according to the invention is described hereinbelow. An elastic leaf spring is used as a member for holding the base of the end guide. The member configuration thereof is adapted so that when the end guide is set at a predetermined place, the end guide is firmly held thereat by using the elasticity of the leaf spring.

FIG. 18

is a plan view of the end guide


40


.

FIG. 19

is a bottom view thereof.

FIG. 20

is a side view thereof.

FIG. 21

is a front view thereof. The end guide


40


has a hook


41


provided on the bottom surface thereof. A member for holding the base of the end guide and for regulating the end guide to prevent the end guide from slipping off from the paper loading plate is installed at this hook


41


.

FIG. 21

illustrates a state in which the hook


41


penetrates through the paper loading plate


20


and a member


42


being in contact with the bottom surface of the paper loading plate


20


is attached to the hook


41


. This member


42


has a structure adapted to bend when the end guide


40


is moved and to enable the end guide


40


to easily move without coming off therefrom. In case that this member


42


is made of a metal, there is a fear that foreign sounds are generated between this member and the paper loading plate during an operation of moving the position of the end guide. Thus, a resin sheet member is used as this member


42


. This prevents the generation of foreign sounds.

FIG. 22

illustrates this member (that is, the resin sheet member)


42


. This member


42


is provided with an attaching portion, which is shaped like a rectangle as a whole and has a U-shaped cutout


43


and is bent both the wings to be formed like a trough. Both the wings


44


are elastically displaceable in a direction of an arrow


45


and have bending elasticity. When this member


42


is installed at the end guide, the member


42


can easily be assembled without tools by utilizing the elasticity thereof. When assembling and disassembling this member


42


, tools are unnecessary because of the use of elasticity of this resin sheet member


42


. Thus, the attachment and removal of this member


42


can easily be performed. In this member


42


, a flexible portion thereof to be used for assembling thereof is formed separately from another flexible portion adapted to bend during the movement of the end guide. Concretely, as illustrated in

FIG. 22

, a U-shaped cutout portion


43


is provided in the member


42


for assembling thereof. When the end guide is attached to the tray, a projection member provided inside the U-shaped cutout portion


43


is bent and fitted to the end guide. When the end guide is moved, this member can be operated by bending both the wing portions


44


thereof without bending the projection provided inside the U-shaped cutout. Thus, the end guide does not slip off therefrom during the operation of moving the end guide. Further,

FIG. 23

illustrates a state in which a similar elastic member


46


is installed at a paper end abutting portion of the end guide. This elastic member


46


can easily installed thereat, similarly as the member


42


, and is thus preferable.




Next, a holding member


61


of the retard roll


60


is described hereinbelow. In order to ensure the paper feed performance, a retard roll is required to restrain variation in position as much as possible. Usually, after the retard roll holding member


61


is attached to the tray body


10


, the positioning is performed by using another member. According to the invention, the tray has a structure in which a projection portion for regulating the position of the retard roll holding member


61


is provided in the member


61


and a installing-side positioning member has elasticity. When assembling the tray, the counterpart positioning member can be pushed up and moved to a normal position by the projection portion, which is provided in the retard roll holding member, for regulating the position of the holding member.

FIG. 24

is an explanatory view illustrating an attachment process of attaching the retard roll holding member


61


. The retard roll holding member


61


has a left-hand side attachment shaft


63


and a right-hand side attachment shaft


62


, which are provided at both ends thereof as projections for regulating the position thereof. The shaft


62


is set as a long shaft, while the shaft


63


is set as a short shaft. Further, the retard roll holding member


61


has a positioning member


64


. The positioning member


64


is a flexible plate-like element and operative to abut against a positioning claw


67


at the main body side to prevent the retard roll holding member


621


from laterally moving. On the other hand, an attachment-side frame, to which this holding member


61


is attached, has bearing holes


65


and


66


, into which the attachment shafts


62


and


63


provided at both ends of the retard roll are fitted, respectively and also has the positioning claw


67


adapted to abut against the positioning member


64


to perform positioning. The attachment of the holding member


61


is performed as follows. The holding member


60


A is first positioned as indicated by imaginary lines in FIG.


24


. Then, the long shaft


62


is passed through the bearing hole


65


to the base thereof so that the holding member


61


is pushed up to an attachment position. The positioning member


64


gets on the positioning claw


67


. At that time, the positioning member is elastically deformed. The short shaft


63


is faced to the bearing hole


66


by maintaining the position of the positioning member. When the holding member


61


is moved in a direction in which the short shaft


63


enters the bearing hole


66


, the positioning member


64


coincides with a positioning location of the positioning claw


67


and the holding member


61


is set at a predetermined position so that the holding member


61


is restrained from moving toward the long shaft. The invention provides a structure in which the shafts


62


and


63


and the positioning member


64


are provided in the holding member


61


itself so that the positioning capability is imparted thereto and the elasticity is provided thereto when the tray is assembled.




As is apparent from the foregoing description, the paper feed tray according to the invention employs the snap-fit structure for all the attachments among the members and does not employ screw fastening therefor at all. Therefore, the assembling and disassembling thereof are easily achieved.




Moreover, the paper feed tray according to the invention is constituted only by the members that enable all the steps of tray assembling and disassembling processes from the same direction without changing the orientation of the tray. Therefore, the assembling process is rationalized. Moreover, manipulations and maintenance operations are easily performed.




The paper feed tray according to the invention is configured as described above. Therefore, the paper feed trays can be manufactured at low cost by eliminating complexity of assembling the paper feed tray. Further, when being conscious of recycling and reuse of the components of the paper feed tray, the disassembling of the paper feed tray is easily achieved. The sorting of members of the paper feed tray into members to be recycled or reused and members to be abandoned is instantaneously achieved.



Claims
  • 1. A paper feed tray comprising:a casing; a paper loading plate for loading paper thereon, the paper loading plate provided on a bottom portion of the casing; a side guide for regulating a side portion of a sheet of paper; an end guide for determining a position of a tail edge of a sheet of paper; a paper separating member for separating paper sheet by sheet; a casing attaching/detaching handle; an operation tab attached to the side guide for regulating the paper separating member; and a catching portion for catching the paper separating member, the catching portion formed between the side guide and the operation tab.
  • 2. The paper feed tray according to claim 1,wherein the paper separating member is a paper separating claw; and a fulcrum of the paper feed claw is formed to be integral with a shaft for fitting the operation tab into the side guide.
  • 3. The paper feed tray according to claim 2, further comprising a snap disposed so that a force received by the paper separating claw from paper during supply of paper acts in a direction in which snap-fitting performed on the operation tab to be utilized at assembling of the tray does not become off.
  • 4. A paper feed tray comprising:a tray body; a drawer handle member provided on the tray body, for attaching/detaching the tray body to/from an image forming apparatus, the drawer handle member constituting a part of an exterior cover of the image forming apparatus; and a fixing member having an elastic piece and an engaged portion, wherein the elastic piece is elastically deformable, has an engaging portion, and is provided on one of the tray body and the drawer handle member; the engaged portion and is provided on the other thereof; the tray body and the drawer handle member comprise at least two constituent members; the engaging portion and the engaged portion is engaged with each other to fix the tray body and the drawer handle member to each other.
  • 5. The paper feed tray according to claim 4, wherein the fixing member consists of the elastic piece and the engaged portion.
  • 6. The paper feed tray according to claim 4, wherein when the tray body is attached to and detached from the image forming apparatus, a direction of a force applied to the fixing member is different from a direction in which the engaging portion is engaged with the engaged portion.
  • 7. The paper feed tray according to claim 4, wherein when the tray body is lifted by holding the drawer handle member, a direction of a force applied to the fixing member is different from a direction in which the engaging portion is engaged with the engaged portion.
  • 8. The paper feed tray according to claim 4, wherein a direction in which the engaging portion is engaged with the engaged portion is substantially perpendicular to a direction in which the tray body is attached to and detached from the image forming apparatus.
  • 9. The paper feed tray according to claim 4,wherein the tray body and the drawer handle member are made of different synthetic resins; and the synthetic resin constituting the tray body is a more durable material than that constituting the drawer handle member.
  • 10. The paper feed tray according to claim 4, further comprising a pair of plate-like arm members provided at both end portions of the drawer handle member, respectively, the plate-like members extended in a direction in which the tray body is attached to and detached from the image forming apparatus,wherein a force received from the tray body is applied to each of the arm members in a direction perpendicular to a direction of thickness thereof.
  • 11. The paper feed tray according to claim 10, wherein each of the arm members is provided to abut against a wall surface that is provided on a sidewall of the tray body and extends in a direction substantially perpendicular to the direction in which the tray body is attached to and detached from the image forming apparatus.
  • 12. The paper feed tray according to claim 4, wherein a space is defined adjacent to the elastic piece.
  • 13. The paper feed tray according to claim 12, wherein the space is a concave portion provided in a sidewall of the tray body.
  • 14. A paper feed tray comprising:a tray body; a drawer handle member provided on the tray body, for attaching/detaching the tray body to/from an image forming apparatus and, the drawer handle member constituting a part of an exterior cover of the image forming apparatus; a fixing member for fixing the tray body and the drawer handle member to each other, provided on one of the tray body and the handle drawer member; an arm member having a plate-like shape, being elastically deformable, and extending in a direction in which the tray body is attached to and detached from the image forming apparatus; a fixing portion for positioning and fixing the arm member, provided on the other thereof.
  • 15. The paper feed tray according to claim 14, wherein the arm member is provided to be parallel to a sidewall of the tray body; andthe fixing portion abuts against a plate-thickness surface of the arm member to position and fix the arm member.
  • 16. The paper feed tray according to claim 14, wherein the arm member is elastically deformable in a direction substantially perpendicular to a direction in which the tray body is attached to and detached from the image forming apparatus.
Priority Claims (1)
Number Date Country Kind
2001-203629 Jul 2001 JP
US Referenced Citations (8)
Number Name Date Kind
3907283 Miller Sep 1975 A
4780740 Fukae Oct 1988 A
5163670 Sellers et al. Nov 1992 A
5238238 Shinohara et al. Aug 1993 A
5975517 Lim Nov 1999 A
6332610 Hiura Dec 2001 B1
6364309 Tomatsu Apr 2002 B1
6435499 Tomatsu Aug 2002 B1