HINGE DEVICE AND IMAGE FORMING APPARATUS EQUIPPED WITH GREASE SWEEPER ABUTTING ON SURFACE OF STATIONARY SUPPORT MEMBER WHEN PIVOTAL SUPPORT MEMBER PIVOTALLY MOVES

A hinge device supports a document holder to allow the document holder to open and close with respect to a body of an image forming apparatus. The hinge device includes a stationary support member, a pivotal support member, and a grease sweeper. The stationary support member is provided on the body of the image forming apparatus. The pivotal support member is provided on the document holder and pivotally connected through a pivotal shaft to the stationary support member. The grease sweeper is attached to the pivotal support member. A distal end of the grease sweeper always abuts on a surface of the stationary support member while the pivotal support member pivotally moves.

INCORPORATION BY REFERENCE

This application claims priority to Japanese Patent Application No. 2023-114931 filed on 13 Jul. 2023, the entire contents of which are incorporated by reference herein.

BACKGROUND

The present disclosure relates to hinge devices and image forming apparatuses.

An image forming apparatus, such as a printer, a scanner, a copier or a multifunction peripheral, is equipped with an automatic document conveying device. The automatic document conveying device is mounted by a hinge device to a body of the image forming apparatus pivotally between a closed position where it covers the top surface of the body of the image forming apparatus and an open position where it opens the top surface of the body of the image forming apparatus. In a general image forming apparatus, the top surface of the body of the image forming apparatus is formed of an original glass plate on which an original document to be read is placed. The use of the original glass plate for copying or scanning is a principal feature of the image forming apparatus and, therefore, the hinge device is desired to have a structure capable of stably and smoothly opening and closing the automatic document conveying device.

There is generally known a hinge mechanism for a document conveying device capable of always stably opening and closing the document conveying device. The general hinge mechanism is composed of a plurality of hinge elements. Each hinge element includes: a leg inserted and supported in a support hole formed in a rear end portion of the body of the image forming apparatus; a stationary support frame provided at the top end of the leg; and a pivotal support frame pivotally connected through a pivotal shaft to the stationary support frame. In at least one of the plurality of hinge elements, the stationary support frame and the leg are integrally formed of a single steel plate by bending the single steel plate. Thus, the opening and closing operation of the document conveying device can be always stably performed.

SUMMARY

A technique improved over the aforementioned technique is proposed as one aspect of the present disclosure.

A hinge device according to an aspect of the present disclosure supports a document holder to allow the document holder to open and close with respect to a body of an image forming apparatus. The hinge device includes a stationary support member, a pivotal support member, and a grease sweeper. The stationary support member is provided on the body of the image forming apparatus. The pivotal support member is provided on the document holder and pivotally connected through a pivotal shaft to the stationary support member. The grease sweeper is attached to the pivotal support member. A distal end of the grease sweeper always abuts on a surface of the stationary support member while the pivotal support member pivotally moves.

An image forming apparatus according to another aspect of the present disclosure includes the above-described hinge device and an image forming device. The image forming device forms an image on a sheet.

DETAILED DESCRIPTION

Hereinafter, a description will be given of an embodiment of the present disclosure with reference to the drawings. Throughout the drawings, the same or equivalent parts and components are designated by the same reference characters and further description is omitted.

First, referring toFIG.1, an image forming apparatus1according to this embodiment will be described.FIG.1is a front view showing an internal structure of the image forming apparatus1. Hereinafter, as shown inFIG.1, the top-to-bottom direction of the image forming apparatus1when placed in a general state of use is defined as the top-to-bottom direction herein, and the front-to-rear direction herein is defined by assuming the side where a user stands facing the image forming apparatus1to be the front side of the image forming apparatus1. Furthermore, the direction orthogonal to the top-to-down direction and the front-to-rear direction is defined as the right-to-left direction herein.

The image forming apparatus1is an apparatus that forms an image. As shown inFIG.1, the image forming apparatus1has a body2in an approximately box shape and the body2is internally provided with a sheet feed device3, an image forming device4, a fixing device5, a sheet ejection device6, and a control device.

The sheet feed device3accommodates sheets S, picks up the accommodated sheets S sheet by sheet, and feeds the picked sheet S to the image forming device4. The image forming device4forms an image on the sheet S by toner. The fixing device5fixes the toner image developed on the sheet S. The sheet ejection device6ejects the sheet S with the image formed by the image forming device4to the outside. The control device controls the operation of the image forming apparatus1.

The image forming apparatus1is, for example, a printer, a scanner, a copier or a multifunction peripheral.

Next, a description will be given of the hinge device10according to this embodiment with reference toFIGS.2to5.FIG.2is a perspective view showing the image forming apparatus1with the hinge device10.FIG.3is an enlarged view of the portion III of the hinge device10inFIG.2.FIGS.4and5are vertical cross-sectional views of the hinge device10.FIG.4shows a state where a document holder20is closed, whileFIG.5shows a state where the document holder20is opened. The vertical cross-sectional view herein refers to a cross-sectional view of an object taken along a vertical plane along the front-to-rear direction.

As shown inFIG.2, the top surface of the body2of the image forming apparatus1is formed of an original glass plate7on which an original document to be copied or scanned by the image forming apparatus1is to be placed. The image forming apparatus1includes a document holder20that holds an original document placed on the original glass plate7when copying or scanning the original document.

The document holder20is formed to cover the top surface of the body2of the image forming apparatus1. The document holder20is, for example, a document cover or an automatic document conveying device. The document cover and the automatic document conveying device have a known arbitrary structure.

The hinge device10is a device that supports the document holder20to allow the document holder20to open and close with respect to the body2of the image forming apparatus1. The hinge device10is provided at the rear ends of the body2of the image forming apparatus1and the document holder20.

As shown inFIGS.3to5, the hinge device10includes a stationary support member11, a pivotal support member12, a pivotal shaft13, and a grease sweeper14.

The stationary support member11is provided at the rear end of the body2of the image forming apparatus1. The stationary support member11includes a surface plate111and a pair of side plates112that cover both sides of the surface plate111. The surface plate111and the side plates112are each formed of a plate-like member.

The surface plate111is formed with a plate-like member bent from the front to the rear thereof into an approximately inverted U-shape as viewed from laterally (as viewed from the right or left, as viewed inFIG.4or as viewed inFIG.5). The pair of side plates112have a size to cover respective U-shaped openings formed on the right and left sides of the surface plate111.

The pair of side plates112have respective through holes113formed therein to allow the pivotal shaft13to pass through the through holes113. The through holes113are provided with respective bearings.

The stationary support member11is provided on the body2of the image forming apparatus1in a state where an open end of the approximately U-shape thereof faces downward, the surface plate111extends from the front to the rear, and the pair of side plates112are arranged in the right-to-left direction.

The pivotal support member12is provided on the document holder20and pivotally connected through the pivotal shaft13to the stationary support member11. The pivotal support member12allows the document holder20to pivotally move between a closed position (the position shown inFIG.4) where the document holder20covers the top surface of the body2of the image forming apparatus1and an open position (the position shown inFIG.5) where the document holder20opens the top surface of the body2to the outside.

The pivotal support member12is composed of a front plate121, a back plate122opposed to the front plate121, a pair of side plates123covering between the front plate121and the back plate122from both lateral sides, and a top plate and has an approximately box shape in which one end surface is open. The front plate121, the back plate122, the side plates123, and the top plate are each formed of a plate-like member.

Each of the front plate121and the back plate122has a length in a widthwise direction (the right-to-left direction) larger than the length of the surface plate111of the stationary support member11in the widthwise direction (the right-to-left direction). The front plate121is provided on the document holder20to form the front surface of the pivotal support member12when the document holder20is in the closed position. At this time, the pair of side plates123form the right and left surfaces of the pivotal support member12and the top plate forms the top surface of the pivotal support member12. In other words, when the document holder20is in the closed position, the lower surface of the pivotal support member12is open.

The pivotal support member12includes: a slide member15capable of sliding toward and away from the stationary support member11; and a spring member16that biases the slide member15toward moving the slide member15close to the stationary support member11.

The slide member15has an approximately box shape in which one end surface is open. The slide member15has a size to accommodate the spring member16therein and to be accommodated in the interior of the pivotal support member12. The slide member15is slidably provided in the interior of the pivotal support member12to face its open surface upward when the document holder20is in the closed position. A distal end151of the slide member15(a lower end thereof in the closed position of the document holder20) is formed to allow one side151A thereof extending in the right-to-left direction to always abut on the surface111A of the surface plate111of the stationary support member11while the pivotal support member12pivotally moves with the slide member15disposed in the interior of the pivotal support member12.

The spring member16is formed of, for example, a coiled spring. The spring member16is accommodated in the interior of the slide member15. The spring member16has a length with which it can bias the slide member15toward moving the slide member15close to the stationary support member11by being always compressed by a constituent surface of the distal end151of the slide member15and the top plate of the stationary support member12while the document holder20pivotally moves between its closed position and open position. However, so long as the spring member16can always bias the slide member15toward moving the slide member15close to the stationary support member11, it may have any known arbitrary structure.

The pivotal shaft13has a columnar shape. The pivotal shaft13has a length larger than the length of the surface plate111of the stationary support member11in the widthwise direction and substantially equal to the length of the front plate121of the pivotal support member12in the widthwise direction. The pivotal shaft13is passed through the through holes113in the pair of side plates112of the stationary support member11and then attached to the pair of side plates123of the pivotal support member12. Thus, the pivotal support member12can pivotally move with and about the axis of the pivotal shaft13with respect to the stationary support member11and, as a result, the document holder20pivotally moves between its closed position and its open position.

The grease sweeper14is a tool that sweeps grease applied to the surface111A of the surface plate111of the stationary support member11. The grease sweeper14is formed of a resin member having a plate-like shape and having elasticity. The grease sweeper14has a length substantially equal to the length of the surface plate111of the stationary support member11in the widthwise direction.

The grease sweeper14is attached to the pivotal support member12, specifically to a front end152of the distal end surface151of the slide member15. In doing so, the attachment of the grease sweeper14is made to allow a distal end141of the grease sweeper14(an end thereof on the side opposite to the side thereof where the grease sweeper14is attached to the slide member15) to always abut on the surface111A of the surface plate111of the stationary support member11by the elastic force of the grease sweeper14while the pivotal support member12pivotally moves. Thus, a space A accommodating grease G is formed by the distal end141of the grease sweeper14, the distal end151of the slide member15, and the surface111A of the stationary support member11.

The hinge device10is assembled in the following manner. Specifically, the slide member15and the grease sweeper14are positioned to allow the grease G applied to the surface111A of the stationary support member11to be accommodated in the space A between the grease sweeper14located closer to the front of the body2and the one side151A of the distal end151of the slide member15located rearward of the grease sweeper14and abutting on the stationary support member11. In this state, the pivotal shaft13is passed through the through holes113in the side plates112of the stationary support member11, the pivotal support member12is disposed to cover the slide member15and the stationary support member11, and the pivotal shaft13is attached to the side plates123of the pivotal support member12. The hinge device10assembled in this manner is made of, for example, a resin material.

Next, a description will be given of the operations of the hinge device10and the grease sweeper14.

First, when the document holder20is in the closed position where it covers the top surface of the body2of the image forming apparatus1, i.e., the position shown inFIG.4, grease G is accommodated in the space A enclosed by the distal end141of the grease sweeper14, the distal end151of the slide member15, and the surface111A of the stationary support member11.

When the document holder20pivotally moves with and about the axis of the pivotal shaft13to the open position where it opens the top surface of the body2of the image forming apparatus1, i.e., the position shown inFIG.5, the grease sweeper14located frontward of the grease G and always abutting on the surface111A of the stationary support member11moves while sweeping the surface111A of the stationary support member11. Thus, the grease G on a portion of the surface111A of the stationary support member11exposed by opening the document holder20is wiped with the grease sweeper14.

Thereafter, when the document holder20pivotally moves with and about the axis of the pivotal shaft13back to the closed position where it covers the top surface of the body2of the image forming apparatus1, i.e., the position shown inFIG.4, the slide member15is moved in the interior of the pivotal support member12in the direction toward the stationary support member11by the biasing force of the spring member16. Thus, the distal end151of the slide member15always abuts on the surface111A of the stationary support member11while being located rearward of the grease sweeper14and, as a result, the grease G is applied again to the surface111A of the stationary support member11by the distal end151of the slide member15.

In this manner, the grease G moves on the surface111A of the stationary support member11as it is accommodated in the space A, and it is repeatedly wiped and applied again on the surface111A each time the pivotal support member12pivotally moves with respect to the stationary support member11.

Meanwhile, also in the general hinge element described previously, in order to achieve smooth opening and closing of the document conveying device, grease need to be applied to the surface of the stationary support frame on which the pivotal support frame slides. Generally, when the document conveying device is opened, the surface of the stationary support frame is exposed at a position where the original document which is used in the image forming apparatus and the user using the image forming apparatus can touch the surface. At this time, there arise a problem that because the grease adheres to the surface of the stationary support frame, the original document and the user may touch the grease and become stained with it.

Unlike the above, the hinge device10according to this embodiment includes the grease sweeper14abutting on the surface111A of the stationary support member11. With the operation of opening the document holder20, the grease sweeper14wipes grease G applied to the surface111A of the stationary support member11. Thus, the grease G is not left on a portion of the surface111A of the stationary support member11exposed by opening the document holder20and, therefore, the original document and the user can be prevented from touching the grease G applied to the surface of the hinge device10.

Furthermore, in the hinge device10according to this embodiment, the pivotal support member12includes the slide member15and one side151A of the distal end151of the slide member15abuts, at the rear of the grease sweeper14, on the surface111A of the stationary support member11. Thus, with the operation of closing the document holder20, the grease G wiped with the grease sweeper14and accommodated in the space A between the distal end141of the grease sweeper14and the distal end151of the slide member15can be spread and applied again onto the surface111A of the stationary support member11by the distal end151of the slide member15. Hence, it can be prevented that the hinge device10runs out of the grease G and becomes hard to operate.

The description of the embodiment of the present disclosure has so far been given with reference to the drawings. However, the present disclosure is not limited to the above embodiment and can be implemented in various forms without departing from the gist of the present disclosure. The various formations of the disclosure can be made by appropriately combining a plurality of components disclosed in the above embodiment. For example, some of all the components disclosed in the above embodiment may be deleted. For the sake of ease of understanding, the drawings may be schematic representation, primarily of components. The number of components and so on shown in the drawings may be different from those of actual components for convenience of creation of the drawings. The components described in the above embodiment are merely illustrative, not particularly limited, and can be changed variously without substantially departing from the effects of the present disclosure.

For example, although in the above embodiment the pivotal support member12includes the slide member15and the spring member16, the present disclosure is not limited to this. For example, the pivotal support member12may have a structure not including the slide member15and the spring member16. In this case, the grease sweeper14is attached directly to the pivotal support member12. Alternatively, the pivotal support member12may include, instead of the slide member15, an abutment member which is provided fixedly on the pivotal support member12and always abuts, at the rear of the grease sweeper14, on the stationary support member11while the pivotal support member12pivotally moves with respect to the stationary support member11.

INDUSTRIAL APPLICABILITY

The present disclosure is applicable to the fields of hinge devices and image forming apparatuses.