The present invention relates to an electric stapler and, specifically, to an electric stapler in which staple storage capacity is increased to enable a large amount of binding processing.
An electric stapler, which realizes a large amount of binding processing using a staple magazine in which staple sheets composed of parallel bonded linear metal lines are stacked, is widely used as a stand-alone type stapler or such that it is incorporated in a copying machine or the like. The lower-most layer sheet of the stacked staple sheets inside the staple magazine is fed toward right below a driver by a feed pawl included in the staple feed mechanism of the electric stapler disclosed, e.g., in JP 2005-35151A, and the linear staple of the leading end portion of the lower-most layer sheet is bent formed into a gate shape by a forming plate, is driven by the driver to penetrate through papers, and the leg portion of the staple is bent by a clincher situated on the lower surface side of the papers, whereby the papers are bound.
In the electric stapler using the staple magazine with the linear staple sheets stored therein, since the staple sheets in the lower-most layer inside the staple magazine are fed out sequentially, while the electric stapler is in use, the staple sheet in the lower-most layer is being pulled from the inside of the staple magazine toward the staple guide of the electric stapler. Therefore, in a state where the staple sheet mounts on both the inside of the staple magazine and the staple guide of the electric stapler, the staple magazine cannot be taken out but, when the staple sheets are used up, the staple magazine can be replaced.
As described above, in a case where the staple magazine is replaced when the staple sheets are used up, the staple sheet must be used up during the continuous binding processing and the continuous binding processing must be stopped for replacement of the staple magazine. Also, there is found another problem: that is, even when it is previously known that the number of the staple sheets remaining in the staple magazine is small, an operator must start the binding operation and wait for the time of the replacement of the staple magazine.
One or more embodiments of the invention provide an electric stapler which enables a continuous binding processing beyond a capacity of a staple magazine to enhance efficiency of the binding processing.
According to one or more embodiments of the invention, an electric stapler includes a staple sheet storage portion for storing a stack of staple sheets, a magazine storage portion disposed on a rear side of the staple sheet storage portion to store a staple magazine, a first staple feed mechanism operable to pull out a staple sheet from the staple magazine and to feed the staple sheet to the staple sheet storage portion, and a second staple feed mechanism operable to pull out the staple sheet from the staple sheet storage portion and to feed the staple sheet to a driver unit. According to this configuration, a continuous binding processing beyond a capacity of the staple magazine becomes possible.
According to one or more embodiments of the invention, the electric staple further includes a lift mechanism operable to lift up the magazine storage portion.
The first staple feed mechanism feeds the staple sheet to the staple sheet storage portion in a state in which the lift mechanism keeps a height of the staple sheet to be pulled out from the staple magazine higher than a height of an upper surface of the stack of the staple sheets inside the staple sheet storage portion.
According to this configuration, since the staple sheet to be fed to the staple sheet storage portion is moved almost horizontally and is put onto the upper surface of the staple sheets inside the staple sheet storage portion, there is no fear that the staple sheet drops off obliquely inside the staple sheet storage portion to cause a jam.
According to one or more embodiments of the invention, the electric staple further includes a first sensor disposed near a staple sheet pulling-out opening of the magazine storage portion to detect whether a staple sheet is present or not, and control means. If the first sensor does not detect a presence of the staple sheet during a certain times of staple sheet feeding operations of the first staple feed mechanism, the control means judges that there are no staple sheets inside the staple magazine and displays or warns that there are no staple sheets.
By replacing the staple magazine in accordance with the display or the warning, the staple magazine can be replaced while the staple sheets remain inside the staple sheet storage portion. Thus, by replacing the staple magazine each time it is required, the continuous binding operation of the electric stapler can be executed perpetually.
According to one or more embodiments of the invention, the first staple feed mechanism includes a feed pawl, a feed pawl hold member, and a pusher disposed on a leading end of the feed pawl hold member and having an upper surface which is rearwardly inclined. The pusher is upwardly biased by a biasing member. The pusher is retracted downward when the upper surface thereof is pressed by the staple sheet while the staple sheet is being fed from the magazine storage portion to the staple sheet storage portion. The upper surface projects into a staple sheet feeding passage so that the pusher pushes a rear end of the staple sheet when the staple sheet passes through the pusher. Therefore, the entire staple sheet can be completely fed into the staple sheet storage portion by the pusher.
According to one or more embodiments of the invention, the electric stapler further includes a hold member for holding a staple sheet. A front portion of the magazine storage portion extends toward an upper side of the staple sheet storage portion and is downwardly biased by a biasing member. The hold member is disposed on the front portion of the magazine storage portion to hold the staple sheets inside the staple sheet storage portion in accordance with the downward biasing of the front portion of the magazine storage portion by the biasing member.
According to this configuration, regardless of the number of staple sheets inside the staple sheet storage portion, the staple sheets can be held and thus the staple sheets can be pulled out stably.
According to one or more embodiments of the invention, the lift mechanism includes a ratchet rack provided on the magazine storage portion and extending in a vertical direction, a lift arm to be driven up and down, and a ratchet pawl provided on the lift arm. The ratchet pawl engages with the ratchet rack only when the lift arm is moved up to lift up the magazine storage portion by a certain lift amount.
According to this configuration, with the height of the upper surface of the staple sheets stored inside the staple sheet storage portion and the height of the staple sheet pulling-out opening of the magazine storage portion controlled constant, the staple sheet can always be fed toward the upper surface of the staple sheets inside the staple sheet storage portion almost in a horizontal state, thereby eliminating a fear that the inside of the staple sheet storage portion can be clogged with staple sheets.
According to one or more embodiments of the invention, the electric stapler further includes a gate bar hanging down from a front surface of the magazine storage portion so as to be upwardly and downwardly movable. A back surface of the staple sheet storage portion is formed with an opening. The gate bar constantly closes a portion of the opening on the back surface of the staple sheet storage portion to prevent the staple sheets inside the staple sheet storage portion from moving and dropping out. This can prevent the movement and slippage of the staple sheets inside the staple sheet storage portion regardless of the installation orientation of the electric stapler.
According to one or more embodiments of the invention, the electric stapler further includes a second sensor which detects a position of a feed pawl of the second staple feed mechanism, and control means. If the second sensor detects that the feed pawl is not positioned at a previously set position, the control means does not execute an operation of the first staple feed mechanism to feed the staple sheet from the magazine storage portion to the staple sheet storage portion.
When the magazine storage portion is lifted up to feed the staple sheet, the staple sheets inside the staple sheet storage portion are not held by the magazine storage portion. At this time, when the staple feed mechanism of the staple sheet storage portion starts its staple sheet pulling-out operation, there is a fear of the poor pull-out of the staple sheet. However, owning to provision of the above-mentioned feed pawl position detecting sensor and operation control means, the occurrence of the poor pull-out of the staple sheet can be prevented.
On the respective lower surfaces of the magazine storage portion 11 and staple sheet storage portion 12, there are provided a first staple feed mechanism 13 and a second staple feed mechanism 14 respectively. These two staple feed mechanisms 13 and 14 are to be reciprocated, that is, are moved backward and forward by a staple feed cam lever 16 to be driven by a disc cam 15 shown in
The magazine storage portion 11 is assembled to a frame F3 shown in
The rear portion (staple sheet entrance side) of the hold lever 18 is upwardly biased by a tension coil spring 19. When the magazine storage portion 11 moves upward and the hold lever 18 is detached from the upper surface of the staple sheet S, the rear portion of the hold lever 18 rises upwardly of the front portion thereof, whereby, when a staple sheet is taken in, the rear portion of the hold lever 18 does not obstruct the entrance of the staple sheet.
To replace the magazine, as shown in
As shown in
When the lift arm 21 is moved downward, until the hold lever 18 of the magazine storage portion 11 is contacted with the staple sheet inside the staple sheet storage portion 12 to thereby cause the magazine storage portion 11 to stop its lowering motion, the lift arm 21 and magazine storage portion 11 move downward integrally with each other. After then, the ratchet pawl 22 is removed from the ratchet rack 24 and thus only the lift arm 21 returns to its lower end initial position.
The second staple feed mechanism 14 disposed below the staple sheet storage portion 12 has the same structure as a staple feed mechanism disclosed in JP 2005-35151A, and a slider (not shown), which is biased forwardly by a compression coil spring, forwardly pushes a feed pawl 25 (a check pawl).
The slider and feed pawl 25 can be connected together and detached from each other by click engaging means which is composed of a pawl and a securing portion or the like. When the slider pushes the feed pawl 25 forwardly, the slider and feed pawl are connected together. When the slider moves backward, the slider and feed pawl move backward together unless the feed pawl 25 blocks the backward movement.
In front of the staple sheet exit of the staple sheet storage portion 12, there is disposed a staple sheet detecting lever 26. When no staple sheet is on a staple guide 27 on the stable sheet exit side, the leading end of the staple sheet detecting lever 26 is biased by a spring (not shown) and is thereby projected upwardly from the lower surface of the staple guide 27, while the rear end of the staple sheet detecting lever 26 is rotated downwardly to retract from the passage of the feed pawl 25. In this state, as described above, the slider and feed pawl 25 are allowed to move backward together.
On the other hand, when a staple sheet is on the staple guide 27 on the staple sheet exit side, the leading end of the staple sheet detecting lever 26 is pushed down by the staple sheet, while the rear end thereof is rotated upwardly and is thereby situated in the backward movement passage of the feed pawl 25. In this state, when the feed pawl 25 slightly moves backward, the rear end of the feed pawl 25 is contacted with the stopper portion (not shown) of the rear end of the staple sheet detecting lever 26 to thereby preventing the feed pawl 25 from further moving backward, whereby only the slider is allowed to move backward.
In this manner, when a staple sheet is on the staple guide 27, the feed paws 25 retreats and advances with a short stroke to thereby feed forwardly the staple sheet pulled out upwardly onto the staple guide 27. Also, when the remaining amount of the staple sheet on the staple guide 27 is left little and the leading end of the staple sheet detecting lever 26 is thereby caused to rise, the feed pawl 25 retreats and advances with a full stroke to thereby pull out forwardly the staple sheet inside the staple sheet storage portion 12.
Similarly to the second staple feed mechanism 14 of the staple sheet storage portion 12, the first staple feed mechanism 13, which is disposed on the lower surface of the magazine storage portion 11, includes a slider 28, a feed pawl 29, a compression coil spring 30 and a staple sheet detecting lever 31. The first staple feed mechanism 13 further includes a pusher 32 disposed in front of the feed pawl 29. The pusher 32 is mounted on the leading end of a member holding the feed pawl 29 and is upwardly biased by a biasing member such as a spring (not shown). The upper surface of the pusher 32 is inclined backwardly and thus, when the pusher 32 is pushed from behind by a staple sheet, the pusher 32 can be pushed in downwardly and is thereby allowed to retract from the passage of the staple sheet.
The initial state of the staple feed device shown in
Subsequently, as shown in
As shown in
The movement of the staple sheet S into the staple sheet storage portion 12 is detected by a staple detecting sensor 36 which is disposed in the magazine storage portion 11. As shown in
When no staple sheet S is on the staple guide 33, as shown by a dot and dash line in
After the feed completion is detected by the staple detecting sensor 36, the lift arm 21 is returned to its initial position by the cam mechanism, and the magazine storage portion 11 is moved downward by the compression coil spring 17, whereby the hold lever 18 holds the staple sheets inside the staple sheet storage portion 12 from above.
Also, by monitoring the signal of the staple detecting sensor 36, it can be checked whether a staple sheet is inside the staple magazine M or not. That is, when the staple sheet is present, the signal of the staple detecting sensor 36 in the staple feed operation, as described above, varies off, on and off. On the other hand, when there are no staple sheets, after initiation of the staple feed operation, the signal of the staple detecting sensor 36 does not vary from off to on. Therefore, when the reciprocating operation of the feed pawl is executed two or more times and the staple detecting sensor 36 signal does not turn on, it can be judged that there are no staple sheets. By notifying the absence of the staple sheet using a display plate or a buzzer, at the time when the staple sheet remains inside the staple sheet storage portion 12, the staple magazine M of the magazine storage portion 11 can be replaced. That is, the staple shortage can be prevented and thus the continuous binding operation can be executed perpetually.
Meanwhile, the vertical position of the magazine storage portion 11 varies according to the number of staple sheets inside the staple sheet storage portion 12. However, since there is used a ratchet mechanism as means for engaging the lift arm 21 and magazine storage portion 11 with each other, the lift amount of the magazine storage portion 11 can be kept constant regardless of the vertical portion of the magazine storage portion 11, which also can make constant the position relationship between the staple guide 33 of the lifted magazine storage portion 11 and the upper surface of the staple sheets inside the staple sheet storage portion 12. Therefore, the staple sheet S can be fed out from the magazine storage portion 11 just above the staple sheet S inside the staple sheet storage portion 12, which can prevent the occurrence of such an inconvenience that the fed-out staple sheet S drops off obliquely inside the staple sheet storage portion 12 and the staple sheet storage portion 12 can be clogged with such staple sheet S.
Also, in view of the fact that the vertical position of the magazine storage portion 11 varies in accordance with the number of staple sheets S remaining inside the staple sheet storage portion 12, in order to be able to feed a staple sheet to the staple sheet storage portion 12 regardless of the vertical position of the magazine storage portion 11, the back surface (the surface on the magazine storage portion side 11) of the staple sheet storage portion 12 is formed open. Thus, according to the arrangement specifications of the electric stapler (the electric stapler is not always arranged horizontally) and the installation condition thereof, there is raised a fear that the staple sheets inside the staple sheet storage portion 12 can move backwardly or drop down. As means for preventing the staple sheet S against such backward movement, as shown in
Meanwhile, the above-described operation to feed the staple sheet S from the magazine storage portion 11 to the staple sheet storage portion 12 can be carried out not only while a stapling processing is in execution but also while it is stopped. The timing and interval of the staple sheet feeding operation can be set optionally, and the number of staple sheets to be fed one time can be set optionally.
However, during the staple sheet feeding operation, the magazine storage portion 11 floats upward and thus the staple sheet of the staple sheet storage portion 12 is not held by the hold lever 18 of the magazine storage portion 11. Therefore, it is desirable not to carry out an operation to pull out a next staple sheet from the staple sheet storage portion 12.
In other words, in a state where the staple sheet is not held by the hold lever 18, when the feed pawl 25 of the second staple feed mechanism 14 pulls out an unused staple sheet from the staple sheet storage portion 12, there is a fear that the feed pawl 25 cannot catch the lower surface of the staple sheet but can slip off it, resulting in the poor feeding of the staple sheet.
Therefore, the operation to feed the staple sheet from the magazine storage portion 11 to the staple sheet storage portion 12 may preferably be carried out in a state where the length of the staple sheet on the staple guide 27 of the staple sheet storage portion 12 still remains there a certain degree and thus an operation to pull out a next staple sheet is not started yet.
In order to control the timing of the staple sheet feeding operation, the electric stapler 1 includes means for detecting the remaining amount (length) of the staple sheet being currently fed to the driver. As shown in
The position of the feed pawl 25 of the second staple feed mechanism 14 varies depending on the length (remaining amount) of the staple sheet on the staple guide 27. That is, until the rear end of the staple sheet passes through the leading end position of the staple sheet detecting lever 26, the backward stroke of the feed pawl 25 is limited and is thus caused to move backward with a short stroke. When the leading staple is ejected, the feed pawl 25 is allowed to advance by an amount equivalent to the line diameter of a single staple and also is allowed to move backward by an amount equivalent to the line diameter of a single staple, whereby the feed pawl 25 is caught by a staple one behind (more specifically, between the two staples). In this manner, when the staple sheet still has a remaining amount, the stroke of the feed pawl 25 is equal to the line diameter of a single staple.
On the other hand, when the consumption of the staple sheet on the staple guide progresses and thus the feed pawl 25 is caught by the rear end of the staple sheet, with the consumption of the staple, the feed pawl 25 moves forwardly of the position to which it has advanced up until then.
Accordingly, when the photo interrupter 41 is turned into such an on state as shown in
The present invention is not limited to the above-described embodiments but, of course, various changes and modifications can be made without departing from the technological range of the invention and these changes and modifications also fall within the scope of the invention.
While the present invention has been described heretofore in detail and also with reference to the specific embodiments thereof, it is obvious to a person skilled in the art that various changes and modification are possible without departing from the spirit and scope of the invention.
The present application is based on Japanese Patent Application No. 2005-295167 filed on Oct. 7, 2005 the content of which is incorporated herein by reference.
In an electric stapler, a continuous binding processing beyond a capacity of a staple magazine becomes possible.
Number | Date | Country | Kind |
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2005-295167 | Oct 2005 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2006/319994 | 10/5/2006 | WO | 00 | 4/4/2008 |