Patent Description:
When a sheet is jammed in an image forming apparatus during an image forming operation, a door on a housing of the image forming apparatus is opened to open the inside of the apparatus and manually remove the jammed sheet.

As a sheet remover that removes such as a sheet (e.g., a sheet of paper), <CIT> discloses a sheet remover fixed to an image forming apparatus and including a first arm and a second arm. The first arm and the second arm extend in a direction perpendicular to a sheet conveyance direction in which the sheet is conveyed. One of the first arm and the second arm of the sheet remover is moved to sandwich a jammed sheet in the image forming apparatus. Then, the first arm and the second arm are rotated to wind the sheet around the outer circumferential surfaces of the first arm and the second arm. The sheet remover having the sheet thus wound around the first arm and the second arm is taken out from the image forming apparatus. Thus, the sheet is removed.

The configuration of the sheet remover for removing sheets is not limited to the configuration in which the sheet is sandwiched by the first arm and the second arm extending in the direction perpendicular to the sheet conveyance direction as in <CIT>. The configuration of the sheet remover is open to consideration.

<CIT> <NUM>, <CIT>, <CIT> and <CIT> disclose background art.

In light of the above-described problems, it is an object of the present invention to provide a sheet remover that facilitates the removal of sheets.

In order to achieve the above-mentioned object, there is provided a sheet remover as described in appended claims. According to an embodiment of the present invention, the sheet remover includes a pair of claws and a pair of sheet holding plates. The pair of claws forms an insertion part between the pair of claws into which a sheet is inserted. The pair of sheet holding plates forms a through part between the pair of sheet holding plates through which the sheet is inserted. The through part is located downstream from the insertion part in a sheet insertion direction in which the sheet is inserted.

Accordingly, the sheet can be easily removed.

There are also provided a conveying device incorporating the sheet remover and an image forming apparatus incorporating the conveying device.

For the sake of simplicity, like reference numerals are given to identical or corresponding constituent elements such as parts and materials having the same functions, and redundant descriptions thereof are omitted unless otherwise required.

<FIG> is a plan view of a sheet remover <NUM> according to an embodiment of the present disclosure.

<FIG> is a cross-sectional view of the sheet remover <NUM>. <FIG> illustrates an internal configuration of the sheet remover <NUM>.

The sheet remover <NUM> is used to hold (particularly, wind in the present embodiment) a sheet jammed on the way in a conveying device and take out the sheet to the outside of the conveying device.

As illustrated in <FIG> and <FIG>, the sheet remover <NUM> includes a pair of sheet holding plates <NUM> as a pair of through-part formers, a pair of leading-end claws <NUM> as a pair of insertion-part formers, a gap formation plate <NUM>, and a winding guide <NUM>. The sheet remover <NUM> is a rod-shaped device extending in a direction indicated by a double-headed arrow X, which is a lateral direction in <FIG>. In the following description, the direction that is indicated by the double-headed arrow X may be referred to as a longitudinal direction X of the sheet remover <NUM> or simply as the longitudinal direction X. The longitudinal direction X is a sheet insertion direction in which the sheet is inserted into the sheet remover <NUM>.

An outer circumferential surface of the sheet remover <NUM> includes an outer circumferential face 14a of the winding guide <NUM>. The outer circumferential face 14a of the winding guide <NUM> is a winding portion along which the sheet is wound.

An operator holds a holding part <NUM>, which is a right portion of the sheet remover <NUM> in <FIG>. Specifically, in the sheet remover <NUM>, the holding part <NUM> is located to the right of a contact face 13a as a contact part, which is a left end of the gap formation plate <NUM> in <FIG> and a downstream end of a through part <NUM> in the sheet insertion direction. The pair of leading-end claws <NUM> is disposed at the left end of the sheet remover <NUM> in <FIG>. A space between the pair of leading-end claws <NUM> is an insertion part <NUM> into which the sheet is inserted. The insertion part <NUM> includes an insertion port at an upstream end of the sheet remover <NUM> in the sheet insertion direction and a downstream portion extending downstream from the insertion port in the sheet insertion direction. The sheet is inserted into the insertion port of the insertion part <NUM> and further inserted downstream in the sheet insertion direction through the downstream portion. The leading-end claw <NUM> includes a curved leading end 12c having a curved surface. The leading end 12c is an upstream end of the leading-end claw <NUM> in the longitudinal direction X.

The pair of sheet holding plates <NUM> is disposed downstream from the pair of leading-end claws <NUM> in the sheet insertion direction. A space between the pair of sheet holding plates <NUM> is the through part <NUM> through which the sheet is inserted from the insertion part <NUM>. In other words, the sheet that is inserted from the insertion part <NUM> passes between the pair of sheet holding plates <NUM> and is held between the pair of sheet holding plates <NUM>.

The pair of sheet holding plates <NUM> sandwich the gap formation plate <NUM> therebetween away from the pair of leading-end claws <NUM> in the longitudinal direction X of the sheet remover <NUM>. The through part <NUM> is located downstream from the insertion part <NUM> in the sheet insertion direction.

The sheet remover <NUM> has an entire length X0 in the longitudinal direction of the sheet remover <NUM> preferably in a range of from <NUM> to <NUM>, and more preferably, in a range of from <NUM> to <NUM>, in a case where the width of a sheet P along a direction perpendicular to a sheet conveyance direction is equal to or smaller than <NUM> inches (about <NUM>). Note that the sheet conveyance direction is a direction in which the sheet P is conveyed. The entire length X0 of the sheet remover <NUM> equal to or greater than <NUM> is sufficient for an operator to hold the holding part <NUM> with both hands without difficulty to hold the sheet P as appropriate and wind the sheet P. A length X3 of the through part <NUM> through which the sheet P is inserted and held by the sheet holding plates <NUM> is preferably about two-thirds or more of the width of the sheet P along the direction perpendicular to the sheet conveyance direction. The aforementioned upper limit of the entire length X0 of the sheet remover <NUM> limits the weight of the sheet remover <NUM> and enhances the operability when the operator uses the sheet remover <NUM>. The sheet remover <NUM> has a diameter of about <NUM>. In the present embodiment, the entire length X0 of the sheet remover <NUM> is about <NUM>. A length X1 in the longitudinal direction of the sheet remover <NUM> between an end of the leading-end claw <NUM> (i.e., a longitudinal end of the sheet remover <NUM>) and the contact face 13a of the gap formation plate <NUM> is about <NUM>. A length X2 of the holding part <NUM> as a distance between the contact face 13a and the other longitudinal end of the sheet remover <NUM> is about <NUM>.

According to the present embodiment, the pair of sheet holding plates <NUM> and the pair of leading-end claws <NUM> are fixed at the respective positions in the sheet remover <NUM> and do not perform an operation such as pinching a sheet when removing the sheet. A description of how to remove the sheet is deferred.

As illustrated in <FIG>, the leading-end claw <NUM> includes a plurality of ribs 12a extending in the longitudinal direction of the sheet remover <NUM>. In other words, the plurality of ribs 12a extends in the sheet insertion direction. The plurality of ribs 12a includes a plurality of guide faces 12a1 inclined toward the through part <NUM> in the sheet insertion direction. The plurality of guide faces 12a1 guides the sheet inserted into the insertion part <NUM> toward the through part <NUM> in the sheet insertion direction. The leading-end claw <NUM> is in a bilaterally symmetrical shape with respect to the central axis of the sheet remover <NUM>, which is an axis parallel to the longitudinal direction of the sheet remover <NUM> and passing through the center in the width direction of the leading-end claw <NUM>.

As illustrated in <FIG>, the interval between the leading-end claws <NUM> decreases rightward in <FIG>. In other words, the length of the insertion part <NUM> in the thickness direction of the sheet that is inserted, which is the vertical direction in <FIG>, decreases toward the back of the sheet remover <NUM>. The pair of sheet holding plates <NUM> that is located behind the insertion part <NUM> has a gap with a width B therebetween, as illustrated in the enlarged view of <FIG>.

The gap with the width B is the through part <NUM>. The leading end 12c as the upstream end of the leading-end claw <NUM> in the sheet insertion direction has a curved surface.

As illustrated in <FIG>, the leading-end claw <NUM> includes a projection 12b at each end in the width direction of the leading-end claw <NUM>. As illustrated in the enlarged view of <FIG>, the projection 12b projects toward the sheet, in other words, toward the vertical center of the sheet remover <NUM> in <FIG>, beyond a sheet holding face 11a of the sheet holding plate <NUM>. In other words, a width A of a gap between the projections 12b is smaller than the width B of the gap between the sheet holding faces 11a of the sheet holding plates <NUM>. In other words, each of the pair of leading-end claws <NUM> includes, at opposed ends in the width direction of each of the pair of leading-end claws <NUM>, portions that narrow the gap between the leading-end claws <NUM>. The portions that narrow the gap function as portions that prevent the sheet inserted through the through part <NUM> from coming off leftward in <FIG>. The projection 12b projecting toward the sheet beyond the sheet holding face 11a smoothly delivers the sheet from the leading-end claw <NUM> to the sheet holding plate <NUM>. The sheet holding face 11a is planar, parallel to the longitudinal direction X.

Referring now to <FIG>, a description is given of an opening and closing configuration in a conveying device in which a sheet is jammed.

In the following description, the sheet P is described as an example of the sheet serving as a recording medium. The sheet or recording medium that is removed by the sheet remover according to the embodiments of the present disclosure is not limited to the sheet P. Examples of the recording medium include, but are not limited to, the sheet P as a sheet of plain paper, thick paper, a postcard, an envelope, thin paper, coated paper such as art paper, tracing paper, an overhead projector (OHP) transparency, a plastic film, a prepreg, and a copper foil.

<FIG> are diagrams illustrating the sheet P jammed on the way along a conveyance passage <NUM> in a conveying device <NUM>.

As illustrated in <FIG>, the conveyance passage <NUM> is defined by a pair of conveyance guide plates <NUM> and <NUM> as a pair of conveyance passage formers. In other words, a gap between the conveyance guide plates <NUM> and <NUM> is part of the conveyance passage <NUM> through which the sheet P is conveyed. The conveyance guide plate <NUM> can be opened and closed by access from the outside.

As illustrated in <FIG>, the sheet P is jammed while being sandwiched at an area of contact, which may be called a nip, between rollers of a conveyance roller pair <NUM> and at an area of contact (i.e., nip) between rollers of a conveyance roller pair <NUM>. The conveyance roller pairs <NUM> and <NUM> are aligned as upstream and downstream conveyance roller pairs along the conveyance passage <NUM> as illustrated in <FIG>.

When the conveyance guide plate <NUM> that is accessible from the outside of the conveying device <NUM> is opened from the state illustrated in <FIG> to the state illustrated in <FIG>, a part of the conveyance passage <NUM> becomes open to the outside of the conveying device <NUM> as illustrated in <FIG>.

The sheet remover <NUM> is inserted into the conveying device <NUM> from the opened space to remove the jammed sheet P to the outside of the conveying device <NUM>.

Although <FIG> illustrate a case where the shaft of the conveyance guide plate <NUM> is parallel to the sheet conveyance direction, the shaft of the conveyance guide plate <NUM> may be perpendicular to the sheet conveyance direction as illustrated in <FIG>.

Now, a detailed description is given of how to wind and remove a sheet with the sheet remover <NUM> described above.

First, as illustrated in <FIG>, an operator holds the holding part <NUM> of the sheet remover <NUM>. Then, as illustrated in <FIG>, the pair of leading-end claws <NUM> of the sheet remover <NUM> is brought close to the sheet P to insert the sheet P into the insertion part <NUM> between the leading-end claws <NUM> as illustrated in <FIG>. At this time, since the leading end 12c of the leading-end claw <NUM> has a curved surface, the sheet P is guided in the insertion part <NUM> in the sheet insertion direction without being caught when the leading end of the sheet P abuts against the leading end 12c.

The leading end of the sheet P that has been inserted into the insertion part <NUM> as illustrated in <FIG> is guided by the plurality of guide faces 12a1 of the leading-end claw <NUM> to relatively move to the back of the insertion part <NUM> and be inserted into the through part <NUM>. With such a shape of the insertion part <NUM> in which the gap between the leading-end claws <NUM> gradually narrows, the sheet remover <NUM> smoothly guides the leading end of the sheet P that has been inserted into the insertion part <NUM> to the through part <NUM>. In other words, simply by inserting the leading end of the sheet P into the insertion part <NUM> and moving the sheet remover <NUM> toward the sheet P, the operator can insert the sheet P through the through part <NUM>. At this time, the projection 12b projecting toward the sheet P beyond the sheet holding face 11a smoothly delivers the sheet P from the leading-end claw <NUM> to the sheet holding plate <NUM>.

Since the leading-end claws <NUM> are in a bilaterally symmetrical shape with respect to the central axis of the sheet remover <NUM> as illustrated in <FIG>, the force is applied laterally equally to the sheet P inserted into the insertion part <NUM> with respect to the central axis of the sheet remover <NUM>. Thus, the sheet P is prevented from being inclined and is smoothly guided to the through part <NUM>.

As illustrated in <FIG>, the contact face 13a of the gap formation plate <NUM> is located at a longitudinal end of the through part <NUM>. The operator moves the sheet remover <NUM> toward the sheet P until the leading end of the sheet P contacts the contact face 13a.

As the gap formation plate <NUM> is sandwiched between the sheet holding plates <NUM>, a gap is formed between the sheet holding plates <NUM>. In other words, in the present embodiment, the width B of the through part <NUM>, which is illustrated in <FIG> as the gap between the sheet holding faces 11a of the sheet holding plates <NUM>, is specified by the thicknesses of the gap formation plate <NUM>. The width B is greater than the maximum thickness of a sheet that is handled by the sheet remover <NUM>. Accordingly, even a sheet having the maximum thickness is smoothly inserted into the through part <NUM>.

After bringing the leading end of the sheet P into contact with the contact face 13a of the gap formation plate <NUM>, the operator rotates the sheet remover <NUM> as indicated by arrows in <FIG> while holding the holding part <NUM>. At the initial stage of the rotation, the sheet P contacts the lateral ends of the sheet holding plates <NUM> or the side of the winding guide <NUM> at two portions Pa and Pb. Since the positions of the portions Pa and Pb are fixed with respect to the sheet remover <NUM> by the rigidity of the sheet P, the sheet P hardly falls off from the sheet remover <NUM> when the sheet remover <NUM> rotates. By rotating the sheet remover <NUM>, the operator winds the sheet P around the outer circumferential face 14a of the winding guide <NUM> as illustrated in <FIG>. Note that <FIG> simplify the shapes of the sheet holding plate <NUM> and the winding guide <NUM>.

As the sheet P is wound up, the sheet P is pulled out from the nip between the conveyance roller pair <NUM> and the nip between the conveyance roller pair <NUM>. Thus, the leading and trailing ends of the sheet P in the sheet conveyance direction are accommodated in the space that is open to the outside as the conveyance guide plate <NUM> is opened. In this state, the operator moves the sheet remover <NUM> in a direction perpendicular to the surface of the paper on which <FIG> is drawn, opposite to the direction in which the sheet remover <NUM> is inserted, to remove the sheet P wound around the sheet remover <NUM> to the outside of the conveying device <NUM>.

As described above, the sheet remover according to the present embodiment includes an insertion part and a through part that is located downstream from the insertion part in the sheet insertion direction. When an operator simply moves the sheet remover toward a sheet (e.g., sheet P) so that the sheet is inserted into the sheet remover, the sheet is inserted into the through part via the insertion part. Thus, the operator can easily remove the sheet from a device such as a conveying device. Since the operator does not have to touch the sheet or the position where the sheet is jammed in the device by hand, the hand of the operator does not get dirty or is not injured by touching, for example, a sheet metal. In addition, for example, when removing the sheet that has passed through a heating device such as a fixing device, the operator can remove the sheet without touching the heated sheet by hand.

In particular, since the sheet remover of the present embodiment does not require an operation such as opening and closing the sheet remover to hold the sheet in the sheet remover, the operator can remove the sheet in a narrower space with the sheet remover of the present embodiment, as compared with a typical sheet remover that is to be opened and closed to hold the sheet. For this reason, the sheet remover of the present embodiment can be used at increased places as compared with the typical sheet remover. In addition, the sheet remover of the present embodiment facilitates the removal of sheets and enhances the user-friendliness of the sheet remover.

Further, the sheet remover of the present embodiment is disposed as a separate component independent of a device such as a conveying device in which a sheet is jammed. Thus, for example, as compared with a sheet remover that is fixed to the conveying device, the sheet remover of the present embodiment can be used at any place into which the sheet remover can be inserted as described above. Thus, the user-friendliness of the sheet remover is enhanced. Since a plurality of sheet removers does not have to be disposed for a plurality of positions where a sheet is jammed, the present embodiment reduces the cost of a device such as a conveying device.

In particular, the sheet remover of the present embodiment includes a winding guide at the outer circumferential surface of the sheet remover. Specifically, in the present embodiment, the operator rotates the sheet remover while keeping the sheet inserted in the through part to wind the sheet and remove the sheet to the outside of the device. Thus, the operator can easily remove the sheet even when the sheet is sandwiched between a conveyance roller pair. If the operator removes the sheet sandwiched between the conveying roller pair with a hand, the operator needs to pull and remove the sheet by hand or wind up the sheet by hand and remove the sheet from the nip between rollers of the conveyance roller pair. However, when the operator pulls and removes the sheet by hand, the operator may have some difficulties in pulling and removing the sheet or may bump the hand in a relatively narrow space in the device. When the operator winds the sheet by hand and removes the sheet from the nip between the rollers of the conveyance roller pair, the operator may have some difficulties in winding and removing the sheet in a relatively narrow space in the device. In addition, since the sheet can be rotated by only <NUM> degrees each time by hand, it takes time to wind the sheet that is relatively long in the sheet conveyance direction. By contrast, the sheet remover <NUM> of the present embodiment allows the operator to easily remove the sheet in a narrower space, as compared with a case where the operator removes the sheet by hand.

The sheet remover of the present embodiment is shaped like a rod extending in the longitudinal direction of the sheet remover parallel to the direction in which the sheet remover is inserted into a device such as a conveying device and the direction in which a sheet is inserted into the sheet remover. The rod shape of the sheet remover decreases a cross-sectional area perpendicular to the longitudinal direction of the sheet remover and allows the sheet remover to be inserted into a relatively narrow space. For example, as illustrated in <FIG>, the cross-sectional area perpendicular to the longitudinal direction of the sheet remover according to the present embodiment is significantly smaller than the size of a human hand. For this reason, the operator can insert the sheet remover even into a narrow place where inserting a hand is difficult and remove a sheet. Thus, the sheet remover of the present embodiment enhances the user-friendliness for the operator to remove the sheet.

As illustrated in <FIG>, an outer circumferential face 12d of the leading-end claw <NUM> is planar, parallel to the longitudinal direction of the sheet remover <NUM>, which is the lateral direction in <FIG>. In other words, the outer circumferential surface of the sheet remover <NUM> includes a planar portion at the leading end of the sheet remover <NUM> adjacent to the insertion part <NUM>, more specifically, at a position around the insertion part <NUM> in the longitudinal direction of the sheet remover <NUM>. When the sheet that is jammed in the conveying device is in close contact with one of the conveyance guide plates (for example, the conveyance guide plate <NUM> illustrated in <FIG>), the operator inserts the leading end of the sheet remover <NUM> between the conveyance guide plate and the sheet while keeping the outer circumferential surface at the leading end of the sheet remover <NUM> in contact with the conveyance guide plate. At this time, since the planar outer circumferential face 12d is hardly caught by the conveyance guide plate, the sheet is smoothly inserted into the insertion part <NUM> and the through part <NUM>.

As illustrated in <FIG>, the outer circumferential face 14a of the winding guide <NUM> as a part of the outer circumferential surface of the sheet remover <NUM> according to the present embodiment has a planar portion 14a1 resulting from cutting off a part of an ellipse. Since the outer circumferential surface of the sheet remover <NUM> includes a planar portion extending in the longitudinal direction of the sheet remover <NUM> at a position not around the insertion part <NUM> (i.e., a position other than the position around the insertion part <NUM>) in the longitudinal direction of the sheet remover <NUM>, the sheet remover <NUM> can be placed at a given position on a placement surface of, for example, a conveying device.

In the cross-section of the winding guide <NUM> in the direction perpendicular to the sheet insertion direction illustrated in <FIG>, diagonal portions of the outer circumferential face 14a of the winding guide <NUM> are curved. Particularly, in the present embodiment, four corners of the outer circumferential face 14a are curved. Such a shape of the winding guide <NUM> increases the winding angle of the sheet P and facilitates the winding of the sheet P, as compared with a case where the four corners are right angles. In the present embodiment, the shape of the outer circumferential face 14a of the winding guide <NUM> is not a circular shape but an elliptical shape having a long diameter portion and a short diameter portion. Such a shape of the winding guide <NUM> allows an operator to easily hold the sheet remover <NUM> and enhances the workability.

The contact face 13a of the gap formation plate <NUM> is a surface perpendicular to the longitudinal direction X. When the leading end of a sheet (e.g., sheet P) contacts the contact face 13a, the posture and inclination of the sheet with respect to the sheet remover <NUM> is corrected. Since the correction of the inclination of the sheet prevents distortion of the sheet while the sheet is wound, the operator easily winds the sheet around the winding guide <NUM>. However, the operator does not always have to insert the sheet into the sheet remover <NUM> until the leading end of the sheet contacts the contact face 13a. For example, when there is no sufficient space for inserting the sheet remover <NUM> into an open space of a device such as a conveying device, the operator may wind the sheet with the sheet remover <NUM> while the leading end of the sheet is not in contact with the contact face 13a.

When the sheet remover <NUM> winds the sheet, the entire width between opposed ends of the sheet in the sheet insertion direction does not have to be accommodated in the through part <NUM> and the insertion part <NUM> of the sheet remover <NUM>. In other words, even when a part of the sheet is outside the sheet remover <NUM>, the part of the sheet outside the sheet remover <NUM> is wound as the sheet in the sheet remover <NUM> is wound. For example, the sheet remover <NUM> can wind a sheet having a length <NUM> times the length X1 between the end of the leading-end claw <NUM> and the contact face 13a of the gap formation plate <NUM> of the sheet remover <NUM> illustrated in <FIG>. The length X1 is preferably equal to or less than the sum of half the length of the conveyance passage in the width direction of the sheet at a position where the sheet is jammed and half the width of the sheet. Accordingly, the sheet can be inserted to the back of the through part <NUM> so that the leading end of the sheet can contact the contact face 13a as appropriate.

As illustrated in <FIG>, a cross-sectional area of a portion corresponding to the leading-end claw <NUM> in the longitudinal direction X of the sheet remover <NUM> gradually increases toward the through part <NUM>. Accordingly, as illustrated in <FIG>, the sheet P that is inserted in the insertion part <NUM> of the sheet remover <NUM> gradually decreases in bending from the leading end of the leading-end claw <NUM>. By contrast, in a case where the sheet P is inserted between leading-end claws <NUM> having a cross-sectional shape in rapid increase as illustrated in <FIG>, the difference in bending becomes too large between a portion of the sheet P inserted in the insertion part <NUM> and a portion of the sheet P not inserted in the insertion part <NUM>. As a result, the sheet P may be broken. If the sheet P is broken, a piece of the sheet P may remain in the conveying device. The above-described configuration of the present embodiment prevents the breakage of the sheet. In particular, an angle α (see <FIG>) of the end of the leading-end claw <NUM> with respect to the longitudinal direction X is preferably equal to or smaller than <NUM> degrees. In this case, the sheet remover <NUM> smoothly scoops the sheet P regardless of the thickness of the sheet P and prevents the sheet P from being broken as illustrated in <FIG>.

Note that <FIG> and <FIG> simplify the shape of the leading-end claws <NUM>.

According to the present embodiment, the cross-sectional shape, perpendicular to the longitudinal direction of the sheet remover <NUM>, of a portion including the through part <NUM> of the sheet remover <NUM> in the longitudinal direction of the sheet remover <NUM> is substantially the same along the longitudinal direction of the sheet remover <NUM>. Accordingly, the operator can easily wind the sheet with the sheet remover <NUM>.

<FIG> illustrate a sheet remover <NUM>' according to another comparative example.

The sheet remover <NUM>' includes a cross-sectional area gradually increasing from a leading-end claw to the back of the sheet remover <NUM>'. When the sheet remover <NUM>' having such a shape winds the sheet P, the sheet P is twisted in the longitudinal direction X as illustrated in <FIG>. For this reason, a greater force is required in this case, as compared with the embodiment described above.

<FIG> illustrate the sheet remover <NUM> according to the present embodiment.

Unlike the sheet remover <NUM>' described above, the sheet remover <NUM> does not twist the sheet P in the longitudinal direction X due to the above-described shape when winding the sheet P, as illustrated in <FIG>. Thus, the operator can easily wind the sheet with the sheet remover <NUM>.

Now, a description is given of an image forming apparatus that includes a conveying device and the sheet remover <NUM> described above.

The image forming apparatus according to the present embodiment includes a storage <NUM> for accommodating the sheet remover <NUM>. Alternatively, the sheet remover <NUM> may be attached to the image forming apparatus or may be placed on a given planar surface of the image forming apparatus without a dedicated portion for accommodating or attaching the sheet remover <NUM>.

As illustrated in <FIG>, an image forming apparatus <NUM> includes, for example, a photoconductor <NUM>, an exposure device <NUM>, a sheet feeding device <NUM>, a conveying device <NUM>, a transfer device <NUM>, a fixing device <NUM>, and an output roller <NUM>.

The sheet feeding device <NUM> includes a plurality of input trays <NUM> and a plurality of sheet feeding rollers <NUM>. The sheet feeding roller <NUM> feeds the sheet P from the corresponding input tray <NUM> to a conveyance passage <NUM>.

A plurality of conveyance roller pairs are disposed along the conveyance passage <NUM> and a reverse conveyance passage <NUM>.

The transfer device <NUM> includes, for example, a primary transfer roller <NUM>, an intermediate transfer belt <NUM>, and a secondary transfer roller <NUM>. A primary transfer nip is formed between the photoconductor <NUM> and the primary transfer roller <NUM>. A secondary transfer nip is formed between the intermediate transfer belt <NUM> and the secondary transfer roller <NUM>. A toner image is transferred from the photoconductor <NUM> onto the intermediate transfer belt <NUM> at the primary transfer nip.

The sheet P that has been fed from the sheet feeding device <NUM> to the conveyance passage <NUM> is conveyed downstream in the sheet conveyance direction, by a plurality of conveyance roller pairs disposed in the conveying device <NUM>, to the secondary transfer nip. After the toner image is transferred onto the sheet P at the secondary transfer nip, the image on the sheet P is fixed by the fixing device <NUM>. The sheet P bearing the fixed image is further conveyed downstream in the sheet conveyance direction and ejected to the outside of the image forming apparatus <NUM> by the output roller <NUM>.

When images are to be formed on both sides of the sheet P, the sheet P is conveyed to the reverse conveyance passage <NUM> at a position downstream from the fixing device <NUM> in the sheet conveyance direction. On the reverse conveyance passage <NUM>, the front and back sides of the sheet P are reversed. Then, the sheet P is conveyed to the conveying device <NUM> again so that another image is formed on the back side of the sheet P in the same manner as the front side of the sheet P. The sheet P bearing images on both sides of the sheet P is ejected to the outside of the image forming apparatus <NUM> by the output roller <NUM>.

As an example, the conveying device <NUM> according to the present embodiment includes a merging portion <NUM> at which the reverse conveyance passage <NUM> merges with the conveyance passage <NUM>, at a position on the conveyance passage <NUM> upstream from the second transfer nip in the sheet conveyance direction.

When a door <NUM> on a housing of the image forming apparatus <NUM> is opened to the front side of the paper on which <FIG> is drawn, the merging portion <NUM> and the surrounding area of the merging portion <NUM> become open to the outside of the image forming apparatus <NUM>. Then, the sheet remover <NUM> according to the present embodiment can remove the sheet P jammed at the merging portion <NUM> or in the surrounding area of the merging portion <NUM>. The sheet remover <NUM> according to the present embodiment may remove the sheet P jammed at a position other than the merging portion <NUM> or the surrounding area of the merging portion <NUM> in the image forming apparatus <NUM>. For example, the sheet remover <NUM> may remove the sheet P jammed at a position downstream from the fixing device <NUM> in the sheet conveyance direction. The conveying device <NUM>, which conveys the sheet P that may be jammed and removed by the sheet remover <NUM> of the present embodiment, is a device that includes a conveyance roller pair on the conveyance passage <NUM> or the reverse conveyance passage <NUM> in the image forming apparatus <NUM> and may be an appropriate part or all of the device. The entire image forming apparatus <NUM> may be a conveying device.

When the door <NUM> is opened, as illustrated in <FIG>, the merging portion <NUM> and part of the conveyance passage <NUM> and the reverse conveyance passage <NUM> around the merging portion <NUM> become open to the outside of the image forming apparatus <NUM> via an opening <NUM> of the housing of the image forming apparatus <NUM>. Specifically, <FIG> illustrates a range surrounded by the one-dot chain line as the opening <NUM> that is opened to the outside of the image forming apparatus <NUM>. For example, an operator accesses the limited space to remove the jammed sheet P.

A part of the conveyance passage <NUM> is defined by conveyance guide plates <NUM> and <NUM> as conveyance passage formers. Another part of the conveyance passage <NUM> including the merging portion <NUM> is defined by a conveyance guide plate <NUM> and a conveyance guide plate <NUM> that is continuous to the conveyance guide plate <NUM>. The conveyance guide plates <NUM> and <NUM> serve as conveyance passage formers.

The conveyance guide plate <NUM> is rotatable about a rotary shaft 106a. The conveyance guide plate <NUM> is rotatable about a rotary shaft 108a. A restraint <NUM> is attached to the conveyance guide plate <NUM>. When the conveyance guide plate <NUM> is closed as illustrated in <FIG>, the restraint <NUM> contacts the conveyance guide plate <NUM> and restrains the conveyance guide plate <NUM> to be closed.

A restraint lever <NUM> is disposed to restrain the conveyance guide plate <NUM> to be closed. The restraint lever <NUM> includes a rotary shaft 111a and a restraint portion 111b. The rotary shaft 111a is fixed to the housing of the image forming apparatus <NUM>. The restraint lever <NUM> is rotatable about the rotary shaft 111a.

In <FIG>, the restraint portion 111b is in contact with the conveyance guide plate <NUM> and restrains the conveyance guide plate <NUM> to be closed. In this state, when the restraint lever <NUM> is rotated about the rotary shaft 111a, the restraint portion 111b is separated from the conveyance guide plate <NUM>. Thus, the conveyance guide plate <NUM> is released from the restraint by the restraint portion 111b. As a result, as illustrated in <FIG>, the conveyance guide plate <NUM> rotates about the rotary shaft 106a by the weight of the conveyance guide plate <NUM> and opens the conveyance passage between the conveyance guide plates <NUM> and <NUM>. The rotation of the conveyance guide plate <NUM> separates the restraint <NUM> from the conveyance guide plate <NUM>. As a result, the conveyance guide plate <NUM> rotates about the rotary shaft 108a and opens the conveyance passage between the conveyance guide plates <NUM> and <NUM>.

After the conveyance passage between the conveyance guide plates <NUM> and <NUM> and the conveyance passage between the conveyance guide plates <NUM> and <NUM> are thus opened, the above-described sheet remover <NUM> enters from the opening <NUM> and is inserted between the conveyance guide plates <NUM> and <NUM> or between the conveyance guide plates <NUM> and <NUM>. Then, the sheet remover <NUM> removes the sheet P jammed in the conveying device <NUM>.

In the present embodiment, the opening <NUM> and the conveyance guide plate <NUM> or the conveyance guide plate <NUM> are arranged such that the sheet remover <NUM> can contact the conveyance guide plate <NUM> or the conveyance guide plate <NUM> through the opening <NUM>. Note that both the conveyance guide plate <NUM> and the conveyance guide plate <NUM> are not opened or closed. When the operator removes the sheet P with the sheet remover <NUM>, such an arrangement allows the operator to insert one of the pair of leading-end claws <NUM> between the sheet P and the conveyance guide plate <NUM> or the conveyance guide plate <NUM> while bringing the leading end of the sheet remover <NUM> into contact with the conveyance guide plate <NUM> or the conveyance guide plate <NUM>, to insert the leading end of the sheet P into the insertion part <NUM> of the sheet remover <NUM>.

A sheet detector may be disposed to detect the sheet P at a position on a conveyance passage that is accessible through an opened door. The sheet detector detects jamming of the sheet P. According to the detection, a notifier provides information that the sheet P is jammed at the position accessible through the opened door. As the notifier, for example, a light emitting element such as a light emitting diode (LED) may be disposed near an opening and closing guide. Alternatively, such information may be notified through an operation screen of the image forming apparatus <NUM>.

In a configuration in which the sheet P is sandwiched between rollers of upstream and downstream conveyance roller pairs disposed along a conveyance passage and temporarily stopped and in which a door is disposed near the position where the sheet P is temporarily stopped such that the position can be accessed, the sheet P is preferably stopped at a position beyond the downstream conveyance roller pair in the sheet conveyance direction. When the sheet P is stopped at the position beyond the downstream conveyance roller pair in the sheet conveyance direction, the sheet P is sandwiched between the rollers of the upstream and downstream roller pairs disposed along the conveyance passage. Accordingly, the sheet P is easily inserted into the insertion part <NUM> of the sheet remover <NUM>.

Referring now to <FIG> and <FIG>, a description is given of a sheet remover according to a modification of the embodiments described above.

The sheet remover according to the present modification enhances usability when an operator, particularly, a general user uses the sheet remover.

As illustrated in <FIG>, the sheet remover <NUM> includes a contact sensor <NUM> on the contact face 13a of the gap formation plate <NUM> and a sheet-type determination sensor <NUM> on the sheet holding plate <NUM>. The sheet remover <NUM> further includes an LED lamp <NUM> as a light on the outer circumferential surface of the sheet remover <NUM>.

The detection state of the contact sensor <NUM> is changed when the sheet P contacts the contact face 13a. Thus, the contact sensor <NUM> detects that the sheet P is in contact with the contact face 13a. As illustrated in <FIG>, when a change in the detection state of the contact sensor <NUM> is transmitted to a controller <NUM> of the sheet remover <NUM>, the controller <NUM> turns on the LED lamp <NUM>. Accordingly, an operator ascertains that the sheet P has been inserted into the back of the sheet remover <NUM> and winds the sheet P as appropriate to remove the sheet P from the image forming apparatus <NUM>. Instead of or in addition to the lighting of the LED lamp <NUM>, the sheet remover <NUM> may notify the operator by sound that the sheet P has been inserted into the back of the sheet remover <NUM>.

The sheet-type determination sensor <NUM> detects the quality and thickness of the sheet P inserted between the pair of the sheet holding plates <NUM>.

The controller <NUM> of the sheet remover <NUM> can communicate with a controller <NUM> of the image forming apparatus <NUM>, which is or includes a conveying device, by wireless communication through, for example, BLUETOOTH or WI-FI connection. Accordingly, the detection state of the contact sensor <NUM> is transmitted to the controller <NUM> of the image forming apparatus <NUM> via the controller <NUM> of the sheet remover <NUM>. When the contact sensor <NUM> is in the detection state, the controller <NUM> can display, on a display panel <NUM>, an explanatory screen prompting a winding operation of the sheet P as in <FIG>.

Referring now to <FIG>, a description is given of an operation procedure when the sheet P causes a jam of the image forming apparatus.

In step S1, the controller <NUM> of the image forming apparatus <NUM> ascertains a paper jam in the image forming apparatus <NUM>.

In step S2, the controller <NUM> of the image forming apparatus <NUM> displays, on the display panel <NUM>, a message prompting the jam clearance with the sheet remover <NUM>.

In response to the message, an operator inserts the sheet P jammed in the image forming apparatus into the through part <NUM> of the sheet remover <NUM> to bring the leading end of the sheet P into contact with the contact face 13a.

As a result, in step S3, the detection state of the contact sensor <NUM> changes. In addition, in step S3, the sheet-type determination sensor <NUM> determines the type of the sheet P.

Then, a change in the detection state of the contact sensor <NUM> is transmitted to the controller <NUM> of the sheet remover <NUM> and further to the controller <NUM> of the image forming apparatus <NUM>. In short, the detection state of the contact sensor <NUM> is transmitted to the controller <NUM> of the image forming apparatus <NUM> via the controller <NUM> of the sheet remover <NUM>.

In step S4, the controller <NUM> turns on the LED lamp <NUM> to inform the operator that the winding operation can be performed. In addition, in step S4, the controller <NUM> of the image forming apparatus <NUM> displays, on the display panel <NUM>, a screen explaining how to wind the sheet P with the sheet remover <NUM>. Thus, the controller <NUM> of the image forming apparatus <NUM> prompts the operator to wind the sheet P.

When the sheet P is removed with the sheet remover <NUM>, in step S5, the controller <NUM> of the image forming apparatus <NUM> ascertains that the jam clearance is completed, in other words, the jammed sheet P is removed from the image forming apparatus <NUM>.

When the sheet P is removed without using the sheet remover <NUM>, for example, when the sheet P is removed by hand, in step S5, the controller <NUM> of the image forming apparatus <NUM> also ascertains the completion of the jam clearance.

In step S6, the controller <NUM> of the image forming apparatus <NUM> determines whether the jam clearance is performed with the sheet remover <NUM>, in other words, whether the detection state of the contact sensor <NUM> is changed upon jam clearance. In addition, in step S6, the controller <NUM> of the image forming apparatus <NUM> determines whether the jam clearance has taken a period of time equal to or longer than a given period of time.

When the sheet remover <NUM> is not used and the jam clearance has taken a period of time equal to or longer than the given period of time (YES in step S6), in step S7, the controller <NUM> of the image forming apparatus <NUM> displays, on the display panel <NUM>, a message prompting the usage of the sheet remover <NUM>. Thus, the controller <NUM> of the image forming apparatus <NUM> prompts the operator to use the sheet remover <NUM> next time and thereafter to perform the jam clearance in a shorter period of time.

On the other hand, when the sheet remover <NUM> is used or the jam clearance has not taken a period of time equal to or longer than the given period of time (NO in step S6), in step S8, the controller <NUM> of the image forming apparatus <NUM> determines whether the quality and thickness of the sheet P determined with the sheet-type determination sensor <NUM> in step S3 are the same as the quality and thickness set in the image forming apparatus <NUM>.

When the quality and thickness of the used sheet P are different from the set quality and thickness (NO in step S8), in step S9, the setting on the image forming apparatus <NUM> is automatically changed to the setting of the used sheet P. Alternatively, the controller <NUM> of the image forming apparatus <NUM> displays, on the display panel <NUM>, a message prompting the change of setting.

On the other hand, when the quality and thickness of the used sheet P are the same as the set quality and thickness (YES in step S8), the operation procedure that is illustrated in <FIG> is completed.

According to the embodiments of the present disclosure, the configuration of the sheet remover is not limited to the configuration in which the leading-end claws and the sheet holding plates that hold the sheet are fixed as in the above-described embodiment.

For example, in the embodiment illustrated in <FIG>, the sheet remover <NUM> includes winding guides 14A and 14B as a part of the outer circumferential surface of the sheet remover <NUM>. The sheet holding plate <NUM> is fixed to the inside of each of the winding guides 14A and 14B. The winding guide 14A and one of the sheet holding plates <NUM> are opened and closed relative to the winding guide 14B and the other of the sheet holding plates <NUM> in the direction indicated by the double-headed arrow in <FIG> or <FIG>. The winding guide 14A and the one of the sheet holding plates <NUM> are opened and closed in an appropriate mechanism by an appropriate operation performed by an operator such as a button operation or an opening and closing operation. In the sheet remover <NUM> of the present embodiment, the pair of sheet holding plates <NUM> sandwiches the sheet placed therebetween by the opening and closing operation. By rotating the sheet remover <NUM> sandwiching the sheet, the operator winds the sheet around the outer circumferential surfaces of the winding guides 14A and 14B. Thereafter, by taking out the sheet remover <NUM> from a device such as a conveying device, the operator removes the sheet jammed inside the device such as the conveying device. The pair of sheet holding plates <NUM> may press against both sides of the sheet to sandwich the sheet by the above-described opening and closing operation of the sheet holding plates <NUM> as in the present embodiment, or the sheet may be held between the sheet holding plates <NUM> as in the embodiment illustrated in, for example, <FIG>.

Claim 1:
A sheet remover (<NUM>) comprising:
a pair of claws (<NUM>) forming an insertion part (<NUM>) between the pair of claws (<NUM>) into which a sheet is inserted; and
a pair of sheet holding plates (<NUM>) forming a through part (<NUM>) between the pair of sheet holding plates (<NUM>) through which the sheet is inserted, the through part (<NUM>) being located downstream from the insertion part (<NUM>) in a sheet insertion direction in which the sheet is inserted, wherein a length of the insertion part (<NUM>) in a thickness direction of the sheet decreases in the sheet insertion direction; and
a contact part (13a) at a downstream end of the through part (<NUM>) in the sheet insertion direction to contact the sheet.