The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2014-197926 filed in Japan on Sep. 29, 2014.
1. Field of the Invention
The present invention relates to a punching device, a paper sheet processing apparatus, and an image forming apparatus.
2. Description of the Related Art
Conventionally, there is known a paper sheet processing apparatus that performs certain post-processing such as punching processing for opening holes, by a punching device, on a paper sheet as a sheet-type recording medium on which an image is formed by an image forming unit of an image forming apparatus.
The punching device of such a kind of paper sheet processing apparatus opens a punch hole on a punching position in the paper sheet conveyed onto a die plate on which a die hole is formed, when a cutting end of a punching pin as a punching member penetrates the paper sheet from one side to the other side and passes through the die hole. The invention described in Japanese Patent No. 4401367 is known as the punching device.
The punching device of Japanese Patent No. 4401367 includes a discharging member discharging electricity on punch chips generated by opening punch holes by contact, in the upper end opening of a punch chip storing container for storing punch chips.
However, in the punching device of Japanese Patent No. 4401367, punch chips are brought into contact with the discharging member only by the weight of the punch chips. Thus, the contact resistance of the discharging member with the punching chips is high, which prevents electricity to flow easily between the discharging member and the punching chips. As a result, static electricity charged on the punching chips has not been discharged preferably.
Therefore, it is desirable to provide a punching device, a paper sheet processing apparatus, and an image forming apparatus that are capable of preferably discharging static electricity charged on punching chips immediately after punch holes are opened.
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 punching device including: a punching member opens a punch hole on a sheet material on a die plate by penetrating a die hole provided to the die plate; a discharging member discharges static electricity charged on a punching chip generated by opening of the punch hole when the punching chip is guided to fall on the discharging member arranged on a lower side of the die hole and brought into contact with the discharging member; and a pressing member that presses the punching chip on the discharging member against the discharging member.
According to another aspect of the present invention, there is provided a paper sheet processing apparatus, including a punching unit that performs punching processing on a paper sheet, wherein the punching unit includes: a punching member opens a punch hole on a sheet material on a die plate by penetrating a die hole provided to the die plate; a discharging member discharges static electricity charged on a punching chip generated by opening of the punch hole when the punching chip is guided to fall on the discharging member arranged on a lower side of the die hole and brought into contact with the discharging member; and a pressing member that presses the punching chip on the discharging member against the discharging member.
According to still another aspect of the present invention, there is provided an image forming apparatus, including: an image forming unit that forms an image on a recording paper sheet; and a recording paper sheet processing unit that performs certain processing on the recording paper sheet on which the image is formed by the image forming unit, wherein the recording paper sheet processing unit includes a punching unit, the punching unit including: a punching member opens a punch hole on a sheet material on a die plate by penetrating a die hole provided to the die plate; a discharging member discharges static electricity charged on a punching chip generated by opening of the punch hole when the punching chip is guided to fall on the discharging member arranged on a lower side of the die hole and brought into contact with the discharging member; and a pressing member that presses the punching chip on the discharging member against the discharging member.
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.
The following will describe an image forming system 1 including a paper sheet processing apparatus 300 provided with a punching device 200 according to an embodiment of the invention and an image forming apparatus 100 with reference to the enclosed drawings.
In the image forming system 1 illustrated in
The image forming apparatus 100 illustrated in
When the photosensitive drum 102 has received a signal instructing the start of image forming action from a control unit (not illustrated) of the image forming apparatus, the photosensitive drum 102 starts rotation in a clockwise direction in
When the toner image formed on the photosensitive drum 102 has reached the transfer part 106 as a transfer unit, the toner image is transferred, by effect of a high voltage applied to the transfer part 106, onto the paper sheet P conveyed along a paper conveyance path K from any of a plurality of paper feeding trays 110. The remaining toner on the photosensitive drum 102 without being transferred even after passing a transfer position is cleaned by the cleaning part 107 so as to prepare for the following image forming action.
The paper sheet P on which the unfixed toner image is formed is passed through a transfer nip of the transfer part 106 and then transferred to the fixing part 109. The fixing part 109 includes a fixing roller 109a and a pressing roller 109b pressed against the fixing roller 109a. The fixing roller 109a and the pressing roller 109b are in contact with each other to form a fixing nip by which the paper sheet P is held. The fixing roller 109a includes therein a heat source (not illustrated) as a heating unit, and the fixing roller 109a is heated by heating of the heat source. The heated fixing roller 109a applies a heating value to the paper sheet P held by the fixing nip so as to heat the paper sheet P. The image on the paper sheet P is fixed by this heating and the influence of nip pressure.
In the case of single-side printing, the paper sheet P passed through the fixing part 109 is conveyed from the image forming apparatus 100 to the paper sheet processing apparatus 300, as illustrated by an arrow A of
The paper sheet processing apparatus 300 includes a control unit (not illustrated) controlling the action of each part. The control unit is a computer including a central processing unit (CPU), a storage, a communication interface, and other components. A conveyance sensor and other devices are connected to the control unit. The control unit (CPU) drive-controls each part of the paper sheet processing apparatus 300 in accordance with a program stored in the storage. The control unit is connected to the control unit (not illustrated) of the image forming apparatus 100 so that they can perform data communication, as described above. The embodiment is not limited to the paper sheet processing apparatus including a punching device, and can be also applied to a single punching device or an image forming apparatus provided with a punching device. The image forming apparatus 100 illustrated in
The following will describe an example of the punching device 200 that is a characteristic part of the invention.
The punching device 200 of the example includes a punching unit 210, a punch chip ejection path 220 (refer to
As illustrated in
As illustrated in
The following will describe the punching action of the punching device 200 of the example having such a configuration with reference to
In the punching device 200 of the example, as illustrated in
With repetition of punching action illustrated in
As illustrated in
As a result of intensive research, the inventors have found that the static electricity occurs strongly when the punching pin 211 passes through the paper sheet with toner on only one side thereof from the surface side with toner and the toner and the punching pin 211 are rubbed each other. In addition, the inventors have found that the static electricity occurs strongly also when the punching pin 211 passes through the paper sheet with toner on both sides thereof and the toner and the punching pin 211 are rubbed each other. The static electricity potential is substantially same regardless of whether the toner with which the punching pin 211 is brought into contact exists on only one side of the paper sheet or on both sides of the paper sheet. Consequently, it has been found that when the toner exists on both sides, the surface side with toner rubbed with the punching pin 211 is charged more strongly. It can be considered that this is because the toner is formed of resin materials and such toner is rubbed with the punching pin, thereby generating static electricity. As illustrated in
The pressing member is not limited to the punching pin 211 as in the example described above, and may be any member as long as it presses the punch chips 240 remaining on the discharging members 215 against the discharging members 215.
Next, one modification of the punching device of the above-described embodiment will be described.
Some examples have been described above. The invention exerts the characteristic effects in each of the following forms.
Form A
A punching device in which a punching member such as the punching pin 211 opens a punch hole on a sheet material on a die plate 214 by penetrating a die hole 213 provided to the die plate 214, a discharging member 215 discharges static electricity charged on a punching chip such as the punch chip 240 generated by opening of the punch hole when the punching chip is guided to fall on the discharging member 215 arranged on the lower side of the die hole and brought into contact with the discharging member 215, the punching device includes a pressing member that presses the punching chip on the discharging member against the discharging member.
In this manner, the punching chips on the discharging members are pressed against the discharging members by the pressing member, whereby the contact pressure of the discharging members with the punching chips is increased, and the contact resistance of the discharging members is decreased, as described in the above embodiment. This facilitates the flow of static electricity charged on the punching chips in the discharging members. Then, the static electricity charged on the punching chips can be discharged preferably.
Form B
In Form A, the pressing member is a punching member such as the punching pin 211. In this manner, the punching member reciprocates through the die hole in the direction orthogonal to the die plate, as described in the above example of the above embodiment. The discharging members are disposed at positions directly under the die hole on the downstream side of the falling direction of the punching chips so that the end of the punching member can press the punching chips against the discharging members when the punching member is moved downward to open a punch hole on a sheet material. In this manner, a discharging of the punching chips charged with static electricity can be performed immediately after the punching chips are generated. Therefore, it is possible to prevent the conventional case in which the punching chips charged with static electricity are attached on a wall surface of the punch chip ejection path provided on the downstream side of the punching direction.
Form C
In Form A or Form B, space for retaining punching chips is formed between the end of the punching member and the discharging members. In this manner, a relatively large amount of punching chips can be retained in the space formed between the end of the punching member and the discharging members, as described in the above example of the above embodiment. The total amount of electric charge of remaining punching chips is increased and then exceeds a certain amount, whereby corona discharge occurs. As a result, the electric charge having reverse polarity to that of the punching chips and the electric charge of the punching chips are coupled to each other, so as to be neutralized electrically. In this way, besides the discharge performed by pressing punching chips against the discharging members, the discharge by corona discharge occurs, thereby improving the discharge performance.
Form D
In Form A to Form C, the discharging member includes a plurality of discharging members, and the ends of the discharging members 215 face each other. In this manner, when the punching chip is passed between the ends of the discharging members, both surfaces of the punching chip are brought into contact with the ends of the discharging members, as described in the above example of the above embodiment. Thus, the static electricity charged on at least one surface of the punching chips can be discharged preferably.
Form E
In Form A to Form D, the discharging member 215 includes a plurality of discharge needles 215a, and the discharge needles are arranged with intervals smaller than a punching chip. In this manner, when the punching chip is passed between the discharge needles, the punching chip is easily brought into contact with the discharge needles, whereby the punching chips can be discharged securely, as described in the above example of the above embodiment.
Form F
In Form D or Form E, the needle ends of the discharge needles 215a arranged to form the discharging members disposed to face each other cross each other when viewed from the arrangement direction of the discharge needles 215a. In this manner, when the punching chip is passed between the needle ends of the facing discharge needles, both surfaces of the punching chip are pressed against the crossing part of the discharge needles, as described in the above example of the above embodiment. The punching chips are strongly pressed against the discharging members so that the crossing amount of the crossing part of the discharge needles is decreased gradually and the gaps between the needle ends of the discharge needles are expanded. As a result, the contact pressure of the discharging members with the punching chips is significantly increased, and the contact resistance of the discharging members is significantly decreased, which facilitates the flow of static electricity charged on the punching chips in the discharging members. Thus, the static electricity charged on at least one surface of the punching chips can be discharged preferably.
Form G
In Form A to Form F, the discharging members are inclined relative to the punching direction. In this manner, the posture of the punching chips becomes vertical, and both surfaces of the punching chips are easily brought into contact with the discharging members, as described in the above example of the above embodiment. Thus, the static electricity charged on at least one surface of the punching chips can be discharged preferably.
Form H
In Form A to Form G, one of the discharging members that are disposed to face each other is provided to be longer than the other discharging member, and the inclination direction of one discharging member is set in accordance with the falling direction of punching chips. In this manner, the falling direction of punching chips can be controlled, which suppresses the case in which the punching chips are stored unevenly in the punch chip storing container for storing punching chips, as described in the above modification of the above embodiment. Therefore, it is possible to prevent full-state detection errors and increase the storage amount of the punch chip storing container.
Form I
In Form A to Form H, the backflow preventing members 218 restricting the movement of punching chips in the opposite direction of the accumulation direction of the punching chips on the discharging members are arranged directly under the die hole. In this manner, the backflow preventing members are arranged directly under the die hole, which prevents the punching chips remaining on the discharging members from passing through the die hole in the opposite direction of the punching direction, as described in the example of the above embodiment. Therefore, it is possible to prevent scattering of punching chips that become obstacles on the die plate after passing through the die hole and avoid paper conveyance jam.
Form J
In Form I, the ends of the backflow preventing members extend toward the center part of the die hole. In this manner, it is possible to securely prevent the punching chips from passing through the die hole, as described in the above Modification 1 of the above embodiment.
Form K
In Form I or Form J, the backflow preventing members 218 are formed of a fiber material. In this manner, it is possible to suppress abrasion of the backflow preventing member and secure the durability, as described in the example of the above embodiment.
Form L
In the paper sheet processing apparatus 300 including a punching unit that performs punching processing on a paper sheet, the punching device 200 of Form A to Form K is used as the punching unit. In this manner, it is possible to preferably discharge static electricity charged on punching chips generated in punching processing of the paper sheet processing apparatus, as described in the above embodiment.
Form M
In the image forming apparatus 100 including an image forming unit that forms an image on a recording paper sheet and a recording paper sheet processing unit that performs certain processing on the recording paper sheet on which an image is formed by the image forming unit, the paper sheet processing apparatus 300 of Form L is used as the recording paper sheet processing unit. In this manner, it is possible to preferably discharge static electricity charged on punching chips generated when the punching processing is performed on the recording paper sheet on which the image is formed by the image forming apparatus.
The present embodiments exert the characteristic effect of preferably discharging static electricity charged on punching chips immediately after punch holes are opened.
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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2014-197926 | Sep 2014 | JP | national |