JPH0929665A - Motor stapler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect defective drive such as buckling of a staple in a motor-driven stapler. SOLUTION: A slit plate 20 is attached to a second link arm 17 interlocked with a driver 14 of a motor stapler 1 to be vertically moved and the displacement of the slit plate 20 is detected by a photointerrupter 23. A control part judges the speed of the driver 14 from the output frequency of the photointerrupter 23 to compare the speed with the reference speed. A plurality of stages of measured time data is stored in the control part and the measured time can be selected according to the thickness of filed sheets of paper. When the driver 14 is instantly stopped immediately before a staple is buckled, the control part judges the staple is buckled and carries out the error process like indication.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric stapler, and more particularly to an electric stapler having a function of detecting a defective driving such as buckling of staples.

[0002]

2. Description of the Related Art When using a stapler, the staples may not be able to penetrate the paper and buckle due to defective forming of the staples or an excessive number of paper sheets, or the buckled staples may be jammed in the driver guide and used for spelling work. May cause problems. In particular, in a copying machine or the like in which a copying machine and an electric stapler are integrally incorporated, if the detection of the improper driving is delayed, the unstitched booklet will be continuously fed. Therefore, if a means for detecting a defective driving of the electric stapler is provided, it is possible to quickly deal with the above situation and prevent a decrease in office work efficiency.

Conventionally, as such a driving failure detecting means, there is known one which monitors the driving current of the motor and detects the occurrence of the driving failure by the change of the current value due to the increase of the load of the motor when the driving failure occurs. .

[0004]

The load and drive current of the electric stapler motor greatly vary depending on the number of sheets to be bound. In particular, the drive current for binding most booklets and the drive current for buckling of staples are almost equal. Therefore, in the conventionally proposed means for detecting defective driving by changing the current value, an overload state such as a driver lock due to a staple jam can be detected, but it is difficult to detect buckling of the staple.

Therefore, the buckling of the staples can be detected immediately so that a quick response can be made, and there arises a technical problem to be solved in order to prevent the work efficiency from being lowered. It aims to solve problems.

[0006]

DISCLOSURE OF THE INVENTION The present invention is proposed in order to achieve the above object, and is provided with a detector for detecting the speed of a driver of an electric stapler driven by an actuator such as a motor. The present invention provides an electric stapler provided with means for sequentially comparing the speed of No. 1 with a reference value and control means for executing error processing such as displaying an abnormal message when the detected speed is less than the reference speed.

In addition to setting the measuring time of the measuring means in a plurality of stages, the measuring time selecting means is provided so that the measuring time corresponding to the thickness of the booklet can be selected, and the booklet to be spelled. (EN) An electric stapler provided with a means for detecting the thickness and a control means for automatically selecting a measurement time suitable for the thickness of the booklet.

The driver of the electric stapler performs a one-cycle operation of descending from the upper home position, coming into pressure contact with the clincher portion and stopping, and then ascending to the upper home position. For example, the driver's speed is sequentially measured by the optical displacement detector until it stops from the home position and stops at the clincher section, and when the detected speed falls below the reference speed, driving such as staple buckling is driven. Judged as defective.

Further, the time from the home position until the driver presses against the paper and stops depends on the thickness of the booklet, but the electric stapler according to claim 2 selects the measurement time by a changeover switch or the like. The speed of the driver during the exercise period can be reliably detected regardless of the thickness of the booklet.

The electric stapler according to claim 3 is
For example, the thickness of the booklet is automatically detected by a thickness detector such as a switch that contacts the surface of the booklet in conjunction with the driver, and the control unit automatically selects the measurement time based on the detected thickness. .

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a chassis of an electric stapler 1, in which a first link arm 4 is attached to a shaft 3 at a rear portion of a frame 2.
And a staple guide 5 are pivotally mounted so as to be vertically rotatable. A motor 6 is arranged below the shaft 3, and the motor 6
Is transmitted to a reduction gear mechanism (not shown).

Eccentric shaft 8 of gear 7 at the front of the reduction gear mechanism
A connecting plate 9 is loosely fitted in the connecting plate 9, and the connecting plate 9 is
Is connected to the link arm 4 via a compression coil spring 10. Rotation of the gear 7 is converted into vertical movement of the connecting plate 9, and the first link arm 4 and the staple guide 5
Moves down and up from the upper standby position shown in FIG. At this time, the staple guide 5 is pressed against the clincher portion 11 at the front of the frame to drive the staples, and then rises and stops, and one cycle of the stapling operation is performed.

The staple guide 5 is provided with a conveyor belt (not shown) extending from the rear to the vicinity of the front end.
The reduction gear mechanism causes the conveyor belt to rotate in conjunction with the lifting operation of the link arm 4. The lower surface of the staple cartridge 12 mounted on the upper rear surface of the staple guide 5 is open, and the lowermost staple sheet stacked in the staple cartridge 12 contacts the conveyor belt and is sequentially transferred forward.

A staple sensor (not shown), which is a reflection type photosensor, is embedded in the rear portion of the staple guide 5 with the light emitting direction directed upward, and the staple sheet in the staple cartridge 12 located above the staple sensor. The presence or absence of is detected by reflected light.

A driver 14 and a forming plate 15 are slidably mounted on the back surface of the face plate 13 at the tip of the staple guide 5 so as to be vertically slidable. , 15a are engaged with holes 4a provided on the left and right side surfaces of the link arm 4.

The shaft 1 provided on the front side surface of the frame 2
A second link arm 17 is pivotally attached to 6 and a pin 19 provided in the intermediate portion of the first link arm 4 is inserted into an elongated hole 18 provided in the intermediate portion of the second link arm 17 to 1
And the second link arms 4 and 17 are connected. Second
The tip end of the link arm 17 is separated into upper and lower parts and protrudes rearward of the frame 2, and a slit plate 20 is installed between the upper and lower ends.

On the slit plate 20, a plurality of slits 21 having the axis 16 as a radiation center are arranged in an arc shape at equal angular intervals, and the light emission of a photointerrupter 23 attached to the rear portion of the frame 2 via a bracket 22. The light receiving unit and the light receiving unit face each other with the slit plate 20 interposed therebetween.

During the stapling operation of the electric stapler 1, the first
Link arm 4 and second link arm 17 interlock, slit plate 20 descends and rises, and the optical path of photointerrupter 23 is interrupted by the rotation of slit plate 20 in the same manner as a general rotary encoder. The signal is input to the control unit.

FIG. 2 shows a circuit block of the electric stapler 1, including a photo interrupter 23, a staple sensor 24,
Further, a paper detection switch 25 arranged near the clincher unit 11 to detect insertion of a paper and a home position sensor 26 are connected to the control unit 27. The home position sensor 26 is composed of a cam plate and a micro switch provided in the reduction gear mechanism, or a rotary light shield plate and a photo interrupter, and has first and second link arms 4, 1.
7 and the staple guide 5 are detected at the upper standby position, and the motor 6 is stopped when the completion of one cycle of operation is detected.

The control unit 27 controls the motor 6 and the display unit 28 in accordance with the output state of each sensor and switch, and executes the spelling operation, message display and the like. The memory 29 of the control unit 27 stores measurement time data of a plurality of stages when measuring the speed of the driver 14, and the changeover switch 3
With 0, the measurement time of the timer unit 31 can be selected according to the thickness of the paper to be bound.

The clock counter 32, which is the speed determining means of the driver 14, is set with a reference clock pulse number corresponding to an abnormality determining reference time slightly longer than the ON / OFF cycle time of the photo interrupter 23 during normal operation of the driver 14. . When the electric stapler 1 is activated, the clock counter 32 starts counting clock pulses, and in normal operation, it is reset by the output pulse signal of the photointerrupter 23 before counting up the reference clock pulse number, and the operation of restarting counting is repeated. . Further, when the reference clock pulse number is counted up, that is, when the speed of the driver 14 decreases and the output frequency of the photo interrupter 23 decreases below the allowable range, it is determined as an error.

FIG. 3 is a graph showing the relationship between the amount of displacement of the driver 14 and time. The time t _CYCLE from the start to the stop of one cycle is the number of sheets of paper except when the driver is locked or when there is an abnormal situation such as idling. It is almost constant regardless.

At the start of spelling, the link arms 4 and 17 and the staple guide 5 descend and the first link arm 4
The driver 14 engaged with the drive drives the leading staple on the staple guide 5 into the paper, and the forming plate 15 forms the staples in the rear row in a gate shape.

The amount of displacement and the time until the driver 14 drives the staples into the paper and stops the descent differ depending on the number of sheets of paper. After the driver 14 has stopped, the connecting plate 9 further compresses the compression coil spring 10 to reach the bottom dead center. Then, the driver 14 moves away from the paper and rises. Then, the home position sensor 26 detects that the link arms 4 and 17 have reached the upper standby position, the motor 6 stops, and the one-cycle stapling operation ends.

The control unit 27 has, for example, as shown in FIG.
The displacement measurement time t in units of 10 _Ten, T₂₀, T₃₀, T
₄₀, T₅₀And rest time t_W10, T_W20, T_W30, T_W40,
t_{W5 0}The time data consisting of
The data is selected by the changeover switch 30.

Next, the buckling detection operation will be described with reference to FIGS. First, when the paper detection switch 25 detects the insertion of paper, the motor 6 is started (step 10
1) The timer unit 31 starts counting the selected time, and the clock counter 32 starts counting the reference clock pulse (step 102).

Immediately after the start of clocking, the process proceeds from step 103 to step 104, and when a reset pulse is input from the photo interrupter 23 before counting the number of reference clock pulses for abnormality determination (step 105), the count value is reset by the ON signal. Then, the counting is restarted (step 106) and the process returns to step 103.

As shown in FIG. 5, when the driver 14 is operating normally, the above-mentioned routine is repeated by the reset pulse S _RESET of the photo interrupter 23,
When the outward measurement time t _n has elapsed, the process proceeds from step 103 to step 107. Then, after a preset pause time t _wn , that is, a time during which the driver 14 is pressed against the paper and stopped, steps 108 to 102 are performed.
Returning to, the driver speed measurement for the return path is performed in the same manner as the above-described forward path, and the process ends when the return path measurement time t _n has elapsed (step 110).

As shown in FIG. 6, when the buckling b occurs, the speed of the driver 14 extremely decreases due to the reaction force of the staple immediately before the staple buckles, and after that, the driver 14 buckles all at once. Speed is reduced below the allowable range, and the reset pulse S of the photointerrupter 23 is reduced.
_When the frequency of _RESET decreases and the clock counter 32 counts up the number of reference clock pulses, step 1
From 04, the process proceeds to step 111 to perform error display and restart prohibition processing. Further, when the forward path operates normally and the speed of the driver 14 decreases in the returning path due to staple clogging or the like, an abnormality is similarly detected and an error process is executed.

FIG. 7 shows an embodiment of the present invention as set forth in claim 3, and a micro switch 33 is attached to the lower surface of the leading end portion of the staple guide 5 to detect the thickness of the booklet P to be bound. The electric stapler 1 is activated, the staple guide 5 is lowered, and the micro switch 33 is set in the booklet P.
The thickness of the booklet P is detected by the time until it comes into contact with the surface of the sheet and is turned on, or by the amount of displacement detected by the slit plate 20 and the photointerrupter 23, and the control unit 27 causes the memory based on the detected thickness. The matching measurement times t _n and t _wn are automatically selected from the measurement time data in 29.

The detector for detecting the displacement of the driver 14 may be a detector such as a differential transformer other than the optical detector, and is not particularly limited. Also,
When the electric stapler is built in the copying machine, the control circuit and the display unit of the copying machine perform the above-mentioned control and display, and the measuring time is selected according to the number of copies data. Various modifications can be made within the scope, and it goes without saying that the present invention extends to those modifications.

[0032]

As described in detail in the above embodiment,
Since the electric stapler of the present invention detects a driving failure such as buckling of staples based on the displacement speed of the driver, the driving failure can be reliably detected regardless of the number of sheets to be bound.

[Brief description of drawings]

FIG. 1 is a side view of an electric stapler showing an example of an embodiment of the present invention.

FIG. 2 is a block diagram of the electric stapler shown in FIG.

FIG. 3 is a timing chart showing the relationship between the displacement of the electric stapler driver and time.

FIG. 4 is a flowchart of driving defect detection of the electric stapler shown in FIG.

FIG. 5 is a graph showing a change in driver speed during normal operation.

FIG. 6 is a graph showing a change in driver speed when buckling occurs.

FIG. 7 is an explanatory view of a staple guide portion showing an embodiment of the invention according to claim 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric stapler 4 First link arm 5 Staple guide 14 Driver 16 Axis 17 Second link arm 18 Slotted hole 19 Pin 20 Slit plate 21 Slit 23 Photo interrupter 27 Control section 33 Micro switch

Claims (3)

[Claims] 1. A detector (20, 23) for detecting the speed of a driver (14) of an electric stapler driven by an actuator such as a motor is provided, and the driver (1) is provided.
An electric stapler provided with means for sequentially comparing the speed in 4) with a reference value and control means for executing error processing such as displaying an abnormal message when the detected speed is less than or equal to the reference speed. 2. The electric stapler according to claim 1, wherein the measuring time of the measuring means is set in a plurality of stages, and the measuring time selecting means is provided so that the measuring time corresponding to the thickness of the booklet can be selected. 3. A means for detecting the thickness of a booklet to be spelled,
The electric stapler according to claim 2, further comprising control means for automatically selecting a measurement time suitable for the thickness of the booklet.