The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2013-024178 filed in Japan on Feb. 12, 2013.
1. Field of the Invention
The present invention relates to a binding apparatus and an image forming apparatus.
2. Description of the Related Art
Conventionally, a binding apparatus that is mounted on or beside an image forming apparatus, such as a copying machine or a printing machine, and that binds a plurality of sheets by using toner as an adhesive is known. The binding apparatus binds a sheet bundle of a plurality of sheets by applying heat and pressure to a portion, which serves as a binding margin and onto which toner is fixed, of the sheets. An example of such a binding apparatus is disclosed in Japanese Laid-open Patent Application No. 2004-209859.
Japanese Laid-open Patent Application No. 2004-209859 discloses a technique related to such a binding apparatus that performs binding using toner. The technique adjusts a period of time, over which the binding margin is pressed, a period of time, over which the binding margin is heated, and a heating temperature depending on a thickness of the sheet bundle to prevent uneven adhesion between the sheets that are adhered together with the toner.
Meanwhile, a binding apparatus that performs binding without using a metal staple is disclosed in Japanese Laid-open Patent Application No. 2010-208854, for example. The binding apparatus performs binding by pressing a portion, which serves as a binding margin, of a sheet bundle of a plurality of sheets with a toothed member, thereby forming grooves and ridges in the binding margin in a thickness direction and bringing the sheets into mesh with each other.
However, conventional binding apparatuses that perform binding using toner have encountered difficulty in adhering sheets of a sheet bundle together with toner evenly, firmly, and efficiently.
For example, because the binding apparatus disclosed in Japanese Laid-open Patent Application No. 2004-209859 adjusts the period of time, over which the binding margin is pressed, the period of time, over which the binding margin is heated, and the heating temperature depending on the thickness of the sheet bundle, a detecting unit and a control unit of the binding apparatus are disadvantageously complicated.
Therefore, it is desirable to provide a binding apparatus capable of, even when the apparatus binds a sheet bundle using toner, adhering sheets of the sheet bundle together with the toner evenly, firmly, and efficiently, and an image forming apparatus including the binding apparatus.
It is an object of the present invention to at least partially solve the problems in the conventional technology.
According to an aspect of the present invention, there is provided a binding apparatus that binds a sheet bundle, the binding apparatus including: an accumulating unit where a plurality of sheets having an area that serves as a binding margin is to be accumulated as the sheet bundle, in which toner is fixed onto all of, or a part of, the area; a pressure unit that sandwiches the binding margin of the sheet bundle stacked on the accumulating unit therebetween and applies a pressure to the binding margin; and a heating unit that heats the toner on the binding margin that is receiving the pressure applied by the pressure unit, wherein the pressure unit is configured to apply the pressure to the binding margin while forming a plurality of grooves and ridges in the binding margin in a direction in which the pressure is applied.
According to another aspect of the present invention, there is provided an image forming apparatus including a binding apparatus that binds a sheet bundle, the binding apparatus including: an accumulating unit where a plurality of sheets having an area that serves as a binding margin is to be accumulated as the sheet bundle, in which toner is fixed onto all of, or a part of, the area; a pressure unit that sandwiches the binding margin of the sheet bundle stacked on the accumulating unit therebetween and applies a pressure to the binding margin; and a heating unit that heats the toner on the binding margin that is receiving the pressure applied by the pressure unit, wherein the pressure unit is configured to apply the pressure to the binding margin while forming a plurality of grooves and ridges in the binding margin in a direction in which the pressure is applied.
The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.
An exemplary embodiment is described below with reference to the accompanying drawings. Like reference numerals and/or symbols identify identical or corresponding elements and portions in the drawings, and repeated description is simplified or omitted.
An overall configuration and operations of an image forming apparatus according to an embodiment is described below with reference to
Referring to
A binding apparatus 50 is a postprocessing apparatus that binds a sheet bundle PT, which is a bundle the sheets P conveyed from the image forming apparatus body 1 via an entry unit 51. The sheet P or the sheet bundle PT is ejected to and stacked on a sheet ejecting unit (stacker unit) 58. The binding apparatus 50 is mounted on or beside the image forming apparatus body 1 to be detachable therefrom.
How the image forming apparatus body 1 operates during normal image forming is described below with reference to
First, the document D is conveyed by conveying rollers of the document conveying unit 10 from a document table in a direction indicated by an arrow in
The optical image data read by the document reading unit 2 is converted into electrical signals and thereafter transmitted to the exposing unit 3 (writing unit). The exposing unit 3 emits the exposure light L, e.g., laser light, toward the photosensitive element 5 of the image forming station 4 based on the image data of the electrical signals.
Meanwhile, the photosensitive element 5 of the image forming station 4 is rotating clockwise in
Thereafter, the image formed on the photosensitive element 5 is transferred onto the sheet P conveyed by the registration rollers 17 and 18 in the transfer unit 7, which is the image forming unit.
Meanwhile, the sheet P is conveyed to the transfer unit 7 (image forming unit) in the following manner.
One sheet feeding unit of the plurality of sheet feeding units 12, 13, and 14 of the image forming apparatus body 1 is manually or automatically selected (in this example, it is assumed that the uppermost sheet feeding unit 12 is selected).
An uppermost one of the sheets P stored in the sheet feeding unit 12 is conveyed toward a conveyance path K.
Thereafter, the sheet P passes through the conveyance path K, on which a plurality of conveying rollers are arranged, and arrives at the registration rollers 17 and 18. The sheet P arrived at the registration rollers 17 and 18 is then conveyed toward the transfer unit 7 (image forming unit) with timing adjusted for registration with the image formed on the photosensitive element 5.
The sheet P undergone a transfer step passes by the transfer unit 7 and thereafter arrives at the fixing device 20 through a conveyance path. The sheet P arrived at the fixing device 20 is delivered into a nip between the fixing roller 21 and the pressure roller 22, at which the image is fixed by heat applied from the fixing roller 21 and a pressure applied from both the pressure roller 22 and the fixing roller 21. The sheet P, onto which the image is fixed, is delivered out from the nip between the fixing roller 21 and the pressure roller 22 and then cooled by the cooling device 25, by which the image is fixed more firmly. Thereafter, the sheet P is ejected from the image forming apparatus body 1.
The sheet P ejected from the image forming apparatus body 1 is further conveyed (delivered) into the binding apparatus 50 via the entry unit 51.
When “NORMAL MODE” is selected by a user in advance from an operation panel (not shown) of the apparatus body 1, a bifurcating claw 52 performs conveyance path switching so that the sheet P is directly ejected to the sheet ejecting unit 58 via a straight conveyance path 55.
On the other hand, when “BINDING MODE” is selected by a user in advance from the operation panel of the apparatus body 1, the bifurcating claw 52 performs conveyance path switching so that the sheet P is conveyed toward an accumulating unit 61 (processing unit) via a processing conveyance path 53. When a plurality of the sheets P has been stacked in the accumulating unit 61 and the desired sheet bundle PT has been formed, the sheet bundle PT is aligned in a width direction and in a conveying direction by movements of jogger fences (not shown). Thereafter, a binding unit 60 binds the sheet bundle PT. Thereafter, the bound sheet bundle PT is conveyed by a conveying roller 56 and a conveying belt 54 to be ejected onto the sheet ejecting unit 58.
The binding apparatus 50 (the binding unit 60) according to the embodiment is configured to bind the sheet bundle PT by using adhesiveness of toner rather than using a metal staple.
More specifically, referring to
The binding unit 60 includes a pressure unit (62, 63, and 65 to 69) and heating unit (heat source 72 and 73). The pressure unit includes a receiving unit 62, a pressing unit 63, a movable plate 65, an elastic member 66, a guide rail 67, an eccentric cam 68, and an extension spring 69. The heating unit includes a ceramic heater 72 and a ceramic heater 73. The pressure unit sandwiches and applies a pressure to the binding margin (the portion indicated by the dotted circle in
The toner T that is fused by heat applied by the heating unit undergoes the pressures applied by the pressure unit and thereafter natural cooling, thereby adhering (binding) the sheets P together.
The receiving unit 62 (fixed unit) is fixed to a bottom side of the accumulating unit 61 in a manner to face the binding margin of the sheet bundle PT placed on the accumulating unit 61.
The pressing unit 63 (movable unit) is disposed on a ceiling side of the accumulating unit 61 in a manner to face the receiving unit 62 across the binding margin of the sheet bundle PT placed on the accumulating unit 61. The pressing unit 63 is configured to be relatively movable toward or away from the receiving unit 62. The pressing unit 63 is fixed onto the movable plate 65 via the elastic member 66 having heat resistance. The movable plate 65 is configured to be slidable on the guide rail 67 in a direction (pressing direction indicated by an arrow in
Because the pressing unit 63 and the receiving unit 62 sandwich and press the binding margin of the sheet bundle PT therebetween, they are preferably made of a rigid material, such as a metal material. The elastic member 66 is for use in adjusting a pressing force to be applied to the binding margin of the sheet bundle PT sandwiched between the pressing unit 63 and the receiving unit 62, and made of an elastic material such as a rubber material.
The heating unit is configured to heat each of the receiving unit 62 and the pressing unit 63. More specifically, the heating unit includes the ceramic heater 72 built in the receiving unit 62 and the ceramic heater 73 built in the pressing unit 63. Electrical power is supplied from a power source (not shown) to each of the heaters 72 and 73 to heat the receiving unit 62 and the pressing unit 63. The receiving unit 62 and the pressing unit 63 heat the binding margin of the sheet bundle PT that is being sandwiched and pressed between the receiving unit 62 and the pressing unit 63. As a result, the toner is heated and fused, and binding is performed.
The receiving unit 62 and the pressing unit 63 are heated by heat conducted from the ceramic heaters 72 and 73 serving as the heat source. Accordingly, the receiving unit 62 and the pressing unit 63 are preferably made of a high-thermal-conductivity material, such as a metal material. In the embodiment, the ceramic heaters are used as the heating unit (the heat source). However, other heat source, such as resistance heating elements, halogen heaters, or electromagnetic induction coils, can alternatively be used as the heating unit. The ceramic heaters 72 and 73 are controlled so as to heat the receiving unit 62 and the pressing unit 63 to a temperature equal to or higher than a melting point of the toner T.
Characteristic configuration and operations of the binding apparatus 50 (the binding unit 60) according to the embodiment are described in detail below.
In the embodiment, the pressure unit of the binding apparatus 50 is configured to press the binding margin of the sheet bundle PT placed on the accumulating unit 61 while forming a plurality of grooves and ridges on the binding margin in the pressing direction.
More specifically, referring to
In the embodiment, the plurality of grooves and ridges formed on the opposing surface 62a of the receiving unit 62 and the opposing surface 63a of the pressing unit 63 have a regular, wave-like pattern in the conveying direction (the direction perpendicular to the width direction) of the sheets P. In the embodiment, the grooves are at intervals of approximately 1 to 2 millimeters; a distance, or height, (depth) between crests of the ridges and bottoms of the grooves is approximately 0.4 to 1 millimeter.
The above configuration brings, even when the surface of each of the sheets P that make up the sheet bundle PT has minute grooves and ridges, the binding margin of the sheet bundle PT pressed between the receiving unit 62 and the pressing unit 63 into close contact while deforming the binding margin in a manner to take the shape of the grooves and ridges of the receiving unit 62 and the pressing unit 63 as illustrated in
The advantage described above of the present embodiment is particularly remarkably advantageous when sheets having rough and irregular grooves and ridges (grains) on their surfaces as does recycled paper are used as the sheets P that make up the sheet bundle PT.
In the embodiment, the grooves and ridges formed on the receiving unit 62 and the pressing unit 63 have the regular, wave-like pattern in the conveying direction of the sheet P. However, the grooves and ridges of the receiving unit 62 and the pressing unit 63 are not limited to those of the embodiment. For instance, the grooves and ridges may be formed in a direction corresponding to the width direction of the sheet P or, alternatively, may be formed to have a matrix-like pattern in directions corresponding to the width direction and the conveying direction of the sheet P. The grooves and ridges may be formed to have, for instance, a substantially needle shape, in which distal ends of the ridges are pointed.
In the embodiment, as illustrated in
Furthermore, in the embodiment, the heating unit stops heating the toner T on the binding margin time t2 earlier than when the pressure unit (pressure mechanism) stops applying the pressure to the binding margin. This control allows reserving time, over which the toner T on the binding margin receives the pressure from the pressure unit while undergoing natural cooling, after the heating unit stops heating. As a result, the binding margin can be adhered firmly.
A configuration illustrated in
In the configuration illustrated in
In a configuration illustrated in
In a configuration illustrated in
In a configuration illustrated in
In the binding apparatus 50 configured as described above, a balance between an amount of heat from the ceramic heaters 72 arranged in the receiving unit 62 and an amount of heat from the ceramic heaters 73 arranged in the pressing unit 63 may be changed. For instance, in a situation where the binding margin receives a higher amount of heat on a side facing the receiving unit 62 than that received on a side facing the pressing unit 63, an amount of heat applied from the ceramic heaters 72 arranged in the receiving unit 62 can be set to be lower than an amount of heat applied from the ceramic heaters 73 arranged in the pressing unit 63, so that heat is applied evenly across the entire binding margin.
In a configuration illustrated in
Although only the configuration of the pressing unit 63 is illustrated in
As described above, in the embodiment, even when binding is performed using the toner T, a plurality of grooves and ridges are formed in a binding margin by the pressure unit (62, 63, and 65 to 69); and, in this state, the toner T on the binding margin is heated by the heating unit (72 and 73). Accordingly, binding can be performed by adhering the sheets P of the sheet bundle PT together with the toner T evenly, firmly, and efficiently.
In the embodiment, the present invention is applied to the binding apparatus 50 mounted on or beside the monochrome image forming apparatus. However, as a matter of course, the present invention is also applicable to a binding apparatus mounted on or beside a color image forming apparatus.
In the embodiment, the present invention is applied to the binding apparatus 50 mounted on or beside the electrophotographic image forming apparatus. However, as a matter of course, the present invention is not limited thereto and also applicable to a binding apparatus mounted on or beside an image forming apparatus of other type (e.g., an inkjet image forming apparatus).
Moreover, the present invention is also applicable to an independent binding apparatus, rather than the binding apparatus 50 connected to the image forming apparatus. Examples of the independent binding apparatus include a binding apparatus including a conveyance port where a sheet feeding cassette is to be placed and an operation panel from which a processing mode and the like are to be entered.
Each of these configurations can provide an effect(s) similar to that (those) provided by the embodiment.
As described above, according to an aspect of the present embodiment, there is provided a binding apparatus that, even when the apparatus performs binding using toner, binds a sheet bundle by adhering sheets of the sheet bundle together with the toner evenly, firmly, and efficiently, and an image forming apparatus including the binding apparatus. This is achieved by causing a pressure unit to form a plurality of grooves and ridges in a binding margin of the sheet bundle and causing a heating unit to heat toner on the binding margin that is being pressed.
Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.
Number | Date | Country | Kind |
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2013-024178 | Feb 2013 | JP | national |