JPH05212180A - Sheet cut-open device - Google Patents

Abstract

PURPOSE:To provide a sheet cut-open device for use with a buttonhole sewing machine, with which certain cut-open operation can be done without any troublesome adjustment even after the cutting edge of a cutter is sharpened and occurrence of any other inconvenience is precluded. CONSTITUTION:A cutter device 13 includes a cutter edge 29 situated at the bottom of a working shaft 23 whose top is coupled with a cutter cylinder 21. Approx. in the middle of this working shaft 23, a slit type shield plate 33 is installed being provided with a number of slits 31 which are located at a certain spacing vertically, and a photo-sensor 35 is installed at a certain level within the zone where the shield plate 33 passes. With this cutter device 13, judgement that the cut-open operation is completed, is passed when no on/off change in the photo-sensor signal is presented for a certain duration while the cutter edge 29 is being sunk by a cutter cylinder 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention penetrates a sheet material and presses it against a member under the sheet material.
An incision means for incising a part of the sheet material, and an operation for operating the incision means along a predetermined path between a standby position and an incision completion position pressed against a member below the sheet material And a sheet material cutting device.

[0002]

2. Description of the Related Art Conventionally, as this type of sheet material cutting device, for example, a cutter device provided in a sewing machine with a buttonholing function (a buttonholing sewing machine) for making buttonholes in fabric has been known. ..

As a cutter device in a conventional buttonhole sewing machine, as shown in FIGS. 10 and 11, an operating shaft 103 having a cutter blade 101 at its lower end is lowered by an air cylinder 105 connected to its upper end. Cutter blade 10
1 through the cloth 107 and the cutter holder 109 thereunder
The buttonhole is cut into the cloth 107 by bringing the cloth 107 into contact with the cloth 107. A shield plate 113 for detecting a predetermined operation position in cooperation with the optical sensor 111 is arranged on the operation shaft 103.

In this buttonhole overedging machine equipped with the conventional cutter device, a buttonhole is first sewn by depressing a start switch (not shown), and then the buttonhole is formed at the center of the stitch which has been finished to be overdone. A series of movements of incising the skin were performed continuously and automatically. During this series of operations, as shown in FIG.
When the air cylinder 105 is driven in the descending direction from the position where the input light to 11 is blocked by the shield plate 113,
As described above, at the position where the cutter blade 101 abuts the cutter receiver 109 to complete the cutting operation, the light blocking by the shield plate 113 is stopped and the optical sensor 111 is turned on. Therefore, when the optical sensor 111 is turned on, it is determined that the incision is completed, the air cylinder 105 is controlled to be turned off, and the cutter blade 10 is cut off.
It was increasing 1.

[0005]

As described above, the optical sensor 1
Since the incision completion position is determined by 11 and the shield plate 113, the incision is surely made, but the conventional device has the following problems.

Since the cutter blade 101 is damaged when it is used for a long period of time, it must be removed from the operating shaft 103 and sharpened after being used to some extent. Then, the cutter blade 101
However, the button hole cannot be surely incised due to insufficient stroke unless any adjustment is made. Therefore, the shield plate 113 is reduced by the amount of sharpening.
Or, if the arrangement of the optical sensor 111 is not adjusted,
There was a problem that the buttonhole could not be reliably cut out.

In order to eliminate such troublesome adjustment,
A configuration is possible in which the descending stroke is set to be sufficiently long from the beginning. In other words, it is conceivable that the optical sensor 111 is continuously lowered for a certain period of time after being turned on, instead of determining whether the incision is completed. However, in this case, the cutter blade 101 is strongly abutted against the cutter receiver 109, which may accelerate its wear or cause breakage, which is not an appropriate countermeasure.

Therefore, the present invention provides a sheet material cutting device which can perform a reliable cutting operation without making a troublesome adjustment even when the cutter blade is sharpened and does not cause other troubles. It was completed for the purpose of doing.

[0009]

The sheet material cutting device of the present invention, which has been made to achieve this object, penetrates the sheet material and presses it against a member below the sheet material to remove the sheet material. A cutting means for cutting a part thereof, and an operating means for operating the cutting means along a predetermined path between a standby position and a cutting completion position pressed against a member under the sheet material. Further, a signal generating means for generating a signal that changes a predetermined amount each time the cutting means moves a predetermined distance along the predetermined path, and a signal change is not given from the signal generating means for a predetermined time or more. In this case, the incision means includes a determination means for determining that the incision completion position has been reached.

[0010]

By adopting such a configuration, according to the sheet material cutting device of the present invention, when the cutting means is lowered by the operating means, the cutting means penetrates the sheet material and is a member below the sheet material. Until it is pressed against, the signal generating means generates a signal that undergoes a predetermined change. Then, when the cutting means penetrates the sheet material and is pressed against the member under the sheet material, the signal from the signal generating means does not change in a predetermined manner. Therefore, the completion of the incision operation can be determined by the absence of the predetermined change in this signal.

As a result, even if the cutting means is sharpened or shortened, the cutting operation can be reliably performed without any particular adjustment.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a preferred embodiment of the sheet material cutting device of the present invention described above, a buttonhole sewing machine having the structure of the present invention will be described. As shown in FIG. 1, the buttonhole sewing machine 1 of the embodiment includes a bed base 3, a bed 5 attached to the bed base 3, and an arm 7 arranged so as to cover the bed 5. There is. A needle 9 is fixed to a lower end of a jaw 7a of the arm 7, and a needle bar 11 for performing an overlock sewing operation of a button hole while swinging the needle in conjunction with an upper shaft (not shown) is attached.
A cutter device 13 is provided in the vicinity of 1 for making a buttonhole by cutting out the center of the portion where the over stitching has been completed. The abdomen 7b of the arm 7 has a cloth presser 15 at its tip.
And a feed arm 17 that reciprocates in conjunction with the upper shaft.

As shown in FIGS. 1 to 3, the cutter device 13 has an air cylinder (hereinafter referred to as a cutter cylinder) 21 arranged on the upper surface 7c of the arm 7 and an upper end connected to the cutter cylinder 21. The operating shaft 23, a mounting plate 25 at the lower end of the operating shaft 23, a cutter holder 27 fixed to the mounting plate 25, and a cutter blade 29 detachably fixed to the cutter holder 27 are provided.

A slit-type shield plate 33 having a large number of slits 31 arranged at equal intervals in the vertical direction is attached to substantially the center of the operating shaft 23. Further, an optical sensor 35 is attached so as to face the slit 31 at a position of a predetermined height within a range where the slit type shield plate 33 passes when the operating shaft 23 moves up and down. The positional relationship between the slits 31 of the slit type shielding plate 33 and the optical sensor 35 in FIGS. 2 and 3 is illustrated as being 90 degrees away from the actual one.
The light sensor 35 has a light emitting element arranged in front of the sheet surface of FIGS. 2 and 3, and a light receiving element arranged behind the sheet surface. The optical sensor 35 includes a slit type shield plate 33.
A signal is generated that turns on when any of the slits 31 is just at the mounting height and turns off when there is a portion other than the slit 31.

In the cutting operation of the cloth 40 by the cutter blade 29, the cutter cylinder 21 is driven in the state of FIG. 2 so that the cutter blade 29 penetrates the cloth 40 and is fixed to the upper surface of the bed 3 fixed to the bed. The buttonhole is incised by lowering the actuating shaft 23 until it comes into contact with 41 (FIG. 3).

In the buttonhole sewing machine 1 of the embodiment, as shown in FIGS. 4 and 5, a needle thread cutting device 50 is further provided near the cutter device 13. In addition, (A) of each figure is a view of the upper thread cutting device 50 as viewed from above,
(B) is a view from the left (button-holing machine 1
(Seeing from the left side of FIG. 1, that is, from the front).

The needle thread cutting device 50 is attached to an air cylinder (hereinafter referred to as scissors cylinder) 51, and is shown in FIG.
The lower scissors 53 that are operated in the direction of the arrow, the upper scissors 55 that are rotatably attached to the upper surface of the lower scissors 53, and the turning range of the folded portion 57 provided at one end of the upper scissors 55 are restricted. The adjusting plate 59 is provided. The adjusting plate 59 is fixed to the jaw 7 a of the arm 7.

The upper thread cutting device 50 is driven after the over stitching of the buttonhole is completed and the incision by the cutter device 13 is completed to cut the upper thread 60. The state of FIG. 4 is a state before the upper thread cutting in which the scissors cylinder 51 is contracted, the rear end 57a of the folded portion 57 contacts the rear portion 59a of the adjusting plate 59, and the upper scissors 55 scissors the lower scissors 53. It is rotated in the opening direction. When the scissors cylinder 51 is extended from this state, the upper scissors 55 first move with the upper scissors 53 open with respect to the lower scissors 53, and the upper thread 60
Scoop between the pair of scissors 53 and 55. Then, when the scissors cylinder 51 is further extended, as shown in FIG. 5, the front end 57b of the folded portion 57 contacts the front part 59b of the adjusting plate 59, and the upper scissors 55 close the scissors with respect to the lower scissors 53. And the upper thread 60 is cut.

These cutter device 13 and needle thread cutting device 50
As shown in FIG. 6, the buttonhole sewing machine 1 including the above is drive-controlled by the control device 70. The control device 70 is a so-called microcomputer including a CPU 71, a ROM 73, a RAM 75, an input port 77 and an output port 79. The presser foot switch 81, the start switch 83, and the optical sensor 35 are connected to the input port 77, and the output arm 79 drives the feed arm 17 in addition to the cutter cylinder 21 and the scissor cylinder 51 to perform the presser foot operation. An air-driven cloth pressing cylinder 85 for performing the cutting, a bobbin thread cutting cylinder 87 for cutting the bobbin thread, and a sewing machine motor 89 are connected.

The buttonhole overlock sewing machine 1 having the above-described structure executes overlock stitching of buttonholes, incision of buttonholes, and cutting of the upper thread and the lower thread in the following procedure. To perform the work, the worker only has to set the cloth 40, press the cloth presser switch 81 to press the cloth, and then press the start switch 83. In response to these operations, the control device 70 executes control processing as shown in FIGS.

The control device 70 firstly detects the presser foot switch 8
After waiting until 1 is turned on (S1: Yes), the cloth presser cylinder 85 is driven and the cloth presser 15 is used to
Is pressed against the cutter receiver 41 (S2). Next, wait until the start switch is turned on (S3: Ye
s), the sewing machine motor 89 is started (S4). And
After sewing a predetermined number of stitches, the sewing machine motor 89 is stopped (S5, S6).

By the operation up to this point, as is conventionally known, the needle bar 11 is moved up and down, the needle swinging device and the shuttle (both not shown) are driven, and further the feed arm 17 is operated to feed the cloth. As a result, the overedging of buttonholes A → B → C → D shown in FIG. 9 is completed.

Next, an ON signal is sent to the cutter cylinder 21 to lower the cutter blade 29 (S7). Then, it waits for the signal from the optical sensor 35 to change from ON to OFF once, and resets the timer counter (S8). That is, the timer counter is reset after confirming that the cutter blade 29 has started to descend from the origin position.
Then, it is determined whether or not the signal from the optical sensor 35 is turned on before the value of the timer counter has passed a predetermined time (S9, S10). Here, before a predetermined time has elapsed (S9:
When the signal from the optical sensor 35 is turned on (No) (S
10: Yes), reset the timer counter again (S
11) Then, it is determined whether or not the signal from the optical sensor 35 has turned off before the value of the timer counter has passed the predetermined time (S12, S13). Here, if the signal from the optical sensor 35 changes to OFF before the elapse of a predetermined time (S12: No) (S13: Yes), the process returns to S8,
The timer counter is reset again, and the processing from S9 onward is repeated. On the other hand, if the signal from the optical sensor 35 does not change by the elapse of the predetermined time (Yes in S9 and S12), an off signal is output to the cutter cylinder 21 (S14). As a result, the cutter blade 29 is raised.

By the operation up to this point, the cutter blade 29 penetrates through the incision E corresponding to the center of the overlock stitches A and C on the button hole side in FIG. 9, and the cutter receiver 41 thereunder.
To complete the incision of the buttonhole. Then, the timing at which the cutter blade 29 collides with the cutter receiver 41 is detected based on the timing when the change in the on / off signal from the optical sensor 35 is no longer observed, and the cutter blade 29 is immediately raised.

When the incision of the button hole is completed, the scissors cylinder 51 is turned on to cut the upper thread (S
15) After that, the scissors cylinder 51 is turned off and the needle thread cutting device 50 is returned to the standby position (S16). Also,
The lower thread cutting cylinder 87 is turned on to cut the lower thread (S1
7) After that, the bobbin thread cutting cylinder 87 is turned off and the bobbin thread cutting device (not shown) is returned to the standby position (S18).
Then, finally, the presser foot cylinder 85 is turned off and the presser foot 15 is raised (S19).

As described above, a series of operations from the buttonhole sewing machine 1 of the present embodiment to the buttonhole sewing, the buttonhole incision, and the cutting of the upper thread and the lower thread are continuous and automatic. To be executed. Then, in the cutting operation, the cutter blade 29 is lowered until the change of the signal from the optical sensor 35 is not seen for a predetermined time, so that the cutting can be surely performed. Therefore, even if the cutter blade 29 is sharpened, it is not necessary to adjust the positional relationship between the respective parts.

Moreover, when this signal change is not seen for a predetermined time, the cutter blade 29 is immediately raised, so that the cutter blade 29 is excessively pressed against the cutter holder to accelerate its wear or cause breakage. There is nothing to do. Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that the present invention can be implemented in various modes without departing from the scope of the present invention.

For example, instead of the slit type shield plate, a black-and-white strip is painted on the operating shaft, and a change in brightness due to this is detected by a sensor, or a concave-convex strip of a magnetic material is provided on the operating shaft. It is also possible to make a change such that a magnetic pickup is provided to face this.

Further, in the embodiment, the slit type shielding plate is provided with slits at equal intervals, but it is also possible to provide slits at unequal intervals. Further, the present invention is not limited to the buttonhole sewing machine as described in the embodiments, but needless to say, the present invention can be variously applied as a cutting device used for other sheet material processing devices.

[0030]

As described in detail above, according to the sheet material cutting device of the present invention, a reliable cutting operation can be performed without making a troublesome adjustment even when the blade of the cutter is sharpened. Moreover, it is possible to obtain a remarkable effect that other problems do not occur.

[Brief description of drawings]

FIG. 1 is a side view showing an overall configuration of a buttonhole overedging machine of an embodiment.

FIG. 2 is a side view of the cutter device used in the embodiment at a standby position.

FIG. 3 is a side view of the cutter device used in the embodiment at the incision completion position.

FIG. 4 is an explanatory view showing a standby state of the needle thread cutting device adopted in the embodiment.

FIG. 5 is an explanatory diagram showing a needle thread cutting completed state of the needle thread cutting device adopted in the embodiment.

FIG. 6 is a block diagram of a control system according to the embodiment.

FIG. 7 is a flowchart showing the first half of the buttonhole forming process in the embodiment.

FIG. 8 is a flowchart showing the latter half of the buttonhole forming process in the embodiment.

FIG. 9 is a plan view illustrating a button hole formed in the example.

FIG. 10 is a side view of a cutter device in a conventional buttonhole overedging machine at a standby position.

FIG. 11 is a side view of the cutter device in the conventional buttonhole sewing machine at the cutting completion position.

[Explanation of symbols]

1 ... Buttonhole sewing machine, 3 ... Bed stand, 5
... Bed, 7 ... Arm, 9 ... Needle, 11 ...
・ Needle bar, 13 ... Cutter device, 15 ... Cloth clamp, 1
7 ... Feed arm, 21 ... Cutter cylinder, 23 ...
・ Operating shaft, 25 ... Mounting plate, 27 ... Cutter holder, 29 ... Cutter blade, 31 ... Slit, 33 ...
..Slit type shielding plate, 35 ... Optical sensor, 40 ...
-Cloth, 41 ... Cutter receiver, 50 ... Upper thread cutting device, 51 ... Scissors cylinder, 53 ... Lower scissors, 55 ... Upper scissors, 57 ... Folding section, 5
9 ... Adjusting plate, 60 ... Upper thread, 70 ... Control device, 77 ... Input port, 79 ... Output port, 8
1 ... cloth presser switch, 83 ... start switch, 85 ... cloth presser cylinder, 87 ... bobbin thread trimming cylinder, 89 ... sewing machine motor.

Claims (1)

[Claims] 1. A cutting means for cutting a part of the sheet material by penetrating the sheet material and being pressed against a member under the sheet material, and a cutting position, a waiting position, and a cutting position of the sheet material. In a sheet material cutting device having an operating means for operating along a predetermined path between a cutting completion position pressed against an underlying member, every time the cutting means moves a predetermined distance along the predetermined path. And a signal generating means for generating a signal which makes a predetermined change, and a judgment for judging that the incision means has reached the incision completion position when the signal change is not given from the signal generating means for a predetermined time or longer. And a sheet material cutting device.