JPH10534A - Operation switch structure and processing equipment control device using this operation switch structure - Google Patents

Abstract

(57) [Summary] [PROBLEMS] When used for starting processing equipment, etc., it has good operability, not only does not cause a startup error, but also processing equipment only when work in all working parts on the processing equipment side is completed. The present invention provides an operation switch structure provided with a work forgetting prevention device as an option that can activate the operation switch. SOLUTION: An operation switch 12 for issuing a start signal for starting the press machine 1 when an operation lever 100 is knocked down, and each of the working units A-1 to G-1 of the press machine 1 is provided.
Is detected by a plurality of operation status detecting means (door open / close detector 4, abnormality detector 5, etc.) and the press machine 1 is operated only when all the pickup signals generated by these operation status detecting means are input. A work forgetting prevention device 6 to be activated is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation switch structure for starting or stopping a processing machine or the like while a worker moves on a U-shaped line, a batch line, or the like, and a processing equipment control device using the operation switch structure. It is.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG.
A one-touch switch 82 is provided for each processing facility 81,
It is known that an operator operates the one-touch switch 82 while walking to operate the processing equipment 81 of the processing line 80.

[0003] The one-touch switch 82 is provided in FIG.
As shown in FIG. 7, a switch body 70 is provided with an operating arm 71 so as to be swingable, a start lever 72 facing downward at the tip of the operating arm 71, a cover 73 provided on the switch body 70, and a cover 73 provided on the switch body 70. To protect the operation arm 71 and provide a stop button 74 on the cover 73.
When the worker moves to the next operation, the activation lever 7 is moved with two fingers.
2 is set aside, the operation arm 71 is operated to generate a start signal, and the processing equipment 81 is started.

[0004]

However, the above-mentioned one-touch switch 82 operates the operating arm 71 by the operator pushing the starting lever 72 sideways with two fingers while moving to the next operation. However, the operability is poor, and when used for starting the processing equipment 81, there has been a problem that a start error occurs, and the one-touch switch 82 has, as a configuration, an optional device for preventing forgetting to work. However, there is a problem that the processing equipment cannot be started only when the work in all the working units on the processing equipment side is completed.

The present invention has been made in view of the above-mentioned problems. A first object of the present invention is that the operability is good. It is an object of the present invention to provide an operation switch structure having an optional work forgetting prevention device that can start the processing equipment only when the work in all the working units on the processing equipment is completed, not only when the operation does not occur.

A second object of the present invention is to provide an operation switch which generates a start signal for activating the processing equipment when an operator moves down the operating lever by hand while walking. Only when the work situation detecting means has issued all the work pickup signals,
An object of the present invention is to provide a processing equipment control device capable of starting the processing equipment.

[0007]

In order to achieve the above object, an operation switch structure according to the first aspect of the present invention includes an operation switch for issuing an activation signal for activating a processing facility when an operation lever is knocked down, A work forgetting prevention device that detects the work status of each work unit of the processing equipment by a plurality of work status detection means and activates the processing equipment only when all of the pickup signals generated by these work status detection means are input. It is characterized by having.

[0008] With this configuration, the operability is good, and when used for starting the processing equipment, etc., not only is there no start-up mistake, but also when the operator knocks down the operating lever, the operation switch activates the processing equipment. However, the work forgetting prevention device can activate the processing equipment only when all of the work status detection means on the processing equipment side have issued all of the work pickup signals.

In order to achieve the first object, the operation switch structure according to the second aspect of the present invention is the processing equipment control device according to the first aspect, wherein: A display unit is provided for selectively lighting and displaying pickup signals emitted by the detection means.

With this configuration, not only can the same operation as the above-described invention of claim 1 be achieved, but also in the work forgetting prevention device, any one of the working units in the processing equipment is not operated. In the case of, the work status detection means does not emit a pickup signal, and emits a pickup signal only for the work unit where the work has been completed,
On the display unit, only the lighting means corresponding to the work part on which the work has been completed is lit, and the lighting means corresponding to the work part on which the work is not performed is not lit. For this reason, it is possible to determine which of the working units in the processing facility is abnormal only by looking at the display unit.

According to a third aspect of the present invention, there is provided an operation switch structure according to the first or second aspect of the present invention, wherein the operation forgetting prevention device is provided. When the operation lever of the operation switch is operated, there is provided an audio means for notifying by an intermittent sound that all operations are not completed.

With this configuration, not only can the same operation as the above-described operation of the first or second aspect of the invention be achieved, but also when the operation forgetting prevention device operates the operating lever of the operation switch, The audio means can notify that all the operations have not been completed by intermittent sounds.
In particular, by combining with a display unit that is displayed as selective lighting, it is possible to more effectively determine which of the working units in the processing equipment is abnormal.

In order to achieve the second object, a processing equipment control device according to a fourth aspect of the present invention includes a plurality of operations for detecting a working state of each working part of the processing equipment and generating a pickup signal. A situation detection means, an operation switch for issuing a start signal for activating the processing equipment when the operation lever is knocked down, and a work forgetting prevention function for operating only when all of the pickup signals emitted by the work situation detection means are input. And a transmission means for transmitting a pickup signal generated by the work status detecting means to the work forgetting prevention device.

[0014] With this configuration, when the operator walks down the operating lever by hand while walking, the operation switch generates a start signal for activating the processing equipment. Only when all the signals are issued, the work forgetting prevention device can start the processing equipment.

According to a fifth aspect of the present invention, there is provided a machining equipment control apparatus according to the fourth aspect of the present invention, wherein the transmission means includes the operation status detecting means. The parallel signal, which is a pickup signal generated by the means, is converted into a serial signal by one parallel-serial converter, and this serial signal is sent to the other parallel-serial converter to be converted into a parallel signal. This is a link terminal that transmits to the input side.

According to this configuration, not only the same operation as the above-mentioned operation of the invention of claim 4 can be achieved, but also the wiring space can be reduced by the link terminal.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

The press machine 1 as a processing facility in which a U-shaped line or the like is installed as a processing line includes a plurality of working units A.
-1 to G-1 (see FIG. 6), and each of these working units A-1 to G-1 has a work situation detecting means. The working unit B-1 is an opening / closing operation unit of the door 2, the working unit D-1 is an abnormality detecting unit of the press machine 1,
The abnormality detection unit has an abnormality lamp 3 that detects an abnormality of the press machine 1 and lights up. Therefore, the work status detecting means of the work unit B-1 is the door open / close detector 4, and the work unit D-
The first work status detecting means is the abnormality detector 5. Further, the press 1 is provided with a connector 69 having a plurality of external input terminals A to G, and these external input terminals A to G are
The work units A-1 to G-1 are connected to respective work status detection means.

The operation switch structure 5 for starting the press machine 1 includes an operation switch structure 5-1 of a basic function type having a function of inputting the number of results as shown in FIG. And the combination of

The operation switch structure 45-1 of the basic function type includes an operation switch 12 as shown in FIGS.
The base 41, the cover 42, the protection guide 43, and the mounting unit 44 are roughly configured, and the base 41 and the cover 42 form a case K.

The operation switch 12 has a case 22 as shown in FIG. 5, and a plunger guide hole 23 is formed in an upper portion of the case 22. The plunger guide hole 23 has a lower plunger. 24 is inserted slidably in the axial direction, and a head 25 having an arc surface 25A is formed at the upper end of the lower plunger 24.
The lower plunger 24 is held while being urged upward by a spring 26.

The lower end of the lower plunger 24 is connected to the upper end of a lower operating plunger 27. An assistant plunger 28 is connected to the lower operating plunger 27. This connection is performed by applying a downward biasing force to the assistant plunger 28 with a spring 29 to lock the end of the assistant plunger 28 with a locking part (not shown) of the lower operating plunger 27. I have.

A movable contact 31 is provided on the lower operating plunger 27 via a reversing spring 30. The movable contact 31 is located between the fixed contacts 32 and 33 and is in contact with the fixed contact 32.

A head 34 is provided at the upper end of the case 22.
The head 34 has an upper plunger 35
The upper plunger 35 is provided with a rod 37 at the upper end thereof via a coil spring 36, and these constitute an operating lever 100. A flange 38 is formed at the lower end of the upper plunger 35. An upper operating plunger 39 is interposed between the flange 38 and the head 25 of the lower plunger 24, and the upper end of the upper operating plunger 39 is flat. The flange 38 of the upper plunger 35 is in contact with the upper end, and the arc surface 25A of the head 25 is in contact with the lower end of the upper operating plunger 39. In this case, the flange portion 38 is in contact with the opening peripheral portion 34A at the upper end of the head 34.

The base 41 has left and right side portions 41A,
It has a U-shape in plan view having 41B and a rear surface portion 41C, and a left and right side surface portions 41A and 41B are provided with screw holes 46 at the top and bottom, and a unit mounting hole 47 at an intermediate portion, respectively. At the upper edges of the left and right side surfaces 41A and 41B, a mounting seat 48 is formed. Also, the rear surface portion 41C
Has a pair of screw holes 49 in the upper part, a pair of screw holes 51 in the middle part, and a cable outlet 52 in the lower part.

The cover 42 has a U-shape in plan view having a front portion 42A, a left portion, right side portions 42B, 42C and a bottom portion 42D. The front portion 42A and the left and right side portions 42B, 42C are formed. A cable outlet 53 is formed on the bottom surface portion 42D, and holes 54 are formed vertically on the left and right side portions 42B and 42C.

The protection guide 43 has a U-shape having upper and lower surfaces 43A and 43B and a rear surface 43C. The inside of the protection guide 43 is accessible only in the direction in which the operating lever 100 is knocked down. A long hole 55 long in the left-right direction and a pair of mounting holes 5
6 are provided.

The mounting unit 44 is mounted on the mounting surface 4.
4A, one end surface portion 44B is provided at one end, and the other end surface portion 44C is provided at the other end of the mounting surface portion 44A.
B has a pair of mounting holes 56 formed therein, the other end surface portion 44C has a screw hole 57 formed therein, and a screw rod 58 is screwed into the screw hole 57. A handle 59 is attached to one end, and a contact plate 60 is attached to the other end.

The operation switch 12 is provided in the base 41.
, And the operation switch 12 is attached to the rear surface portion 41C with a screw, and the base 42 is covered with a cover 42.
The left and right side portions 42B and 42C of the cover 42 are fixed to the left and right side portions 41A and 41B of the base 41 by screws, and the lower surface portion 43B of the guide 43 is screwed to the mounting seat 48 at the upper edge of the base 41. The operation switch 12 is fixed through the long hole 55 provided in the lower surface 43B.
The operating lever 100 (the coil spring 36 connected to the upper plunger 35 and the rod 37 connected to the coil spring 36) is
1 protrudes. The attachment unit 44 is attached to the rear surface portion 41C of the base 41 with screws to form an operation switch structure 45-1.

The cable 61 connected to the operation switch 12 is connected to one of the cable outlets 52, 53.
It has been taken out more.

The operation switch structure 45-1 constructed as described above has a mounting unit 44 as shown in FIG.
Of the screw rod 5 screwed into the screw hole 57 of the other end surface portion 44C
8 is attached to the processing equipment by rotating the handle 8 with the handle 59 and fixing it to the mounting portion S of the processing equipment with the contact plate 60 and the one end surface 45B.

The operation of the operation switch 12 is performed by the operator manually hitting (flicking) the operating lever 100 projecting into the guide 43 from the side while walking. Thus, when the operating lever 100 is hit from the lateral direction, the upper plunger 35 tilts to one side via the coil spring 36. That is, the upper plunger 35 rotates and pushes the upper operating plunger 39 downward with one end of the flange 38 at the lower end of the upper plunger 35 in contact with the opening peripheral portion 34A at the upper end of the head 34. . For this purpose, the upper operating plunger 39 is lowered, and the lower operating plunger 2 is moved through the assistant plunger 28 and the spring 29.
7 descends, the reversing spring 30 reverses, and the movable contact 31 separates from the one fixed contact 32 and comes into contact with the other fixed contact 33, so that the switch is turned on.

Further, the optional unit includes:
A work-forgetting prevention device 6 having a work-forgetting prevention function that is activated only when all of the work pickup signals are input is used. In the device 6 for preventing forgetting to work, the case 66 is provided with a connector 67 having a plurality of external input terminals A 'to G', and the case 66 is provided with external input terminals A 'to G'. A display unit 6 having red light emitting diodes a to g that light up when an input signal is input;
8 are provided. Further, a buzzer 8 which is a voice means is provided at a lower portion of the case 66.

The press machine 1 and the work forgetting prevention device 6 are connected to a link terminal 70 as a transmission means.
Connected by The link terminal 70 includes a programmable controller (hereinafter abbreviated as PC) 7.
1 and a line saving terminal device 72A, 72B. The PC 71 includes a CPU 73 and the CPU 73.
And an output unit 75 located on the output side of the CPU 73. The input unit 74 includes a connector 74A and an output unit 7
5 has connector parts 75A, respectively.

Each of the line saving terminal devices 72A and 72B includes a link terminal 76 with a built-in connector on the transmitting side and a link terminal 77 with a built-in connector on the receiving side.
The transmitting-side built-in connector type link terminal 76 has a parallel / serial converter (not shown) for converting a plurality of parallel signals input to the built-in connector type link terminal 76 into a serial signal. The link terminal 77 with a built-in connector on the receiving side has a parallel-serial converter (not shown) for converting a serial signal taken into the link terminal 77 with a built-in connector on the receiving side into a plurality of parallel signals. The signal connecting terminals (not shown) of the connector built-in link terminals 76 and 77 on the transmitting and receiving sides are connected by signal lines 78, and a positive and negative power connecting terminals (not shown).
The power supply lines 79A and 79B connect between them.

Then, one of the line-saving terminal devices 72A
Is a link terminal 76 with a built-in connector on the receiving side.
Connector (not shown) is connected to the connector 69 on the press 1 side.
The connector (not shown) of the transmitting-side built-in connector type link terminal 77 is fitted and connected to the connector 74A of the input unit 74 of the PC 71. Also, the other line saving terminal device 72B has a connector (not shown) of the built-in connector type link terminal 76 on the receiving side fitted and connected to the connector portion 75A of the output unit 75 of the PC 71, and the transmission side. A connector (not shown) of the connector built-in type link terminal 77 is fitted and connected to the connector 67 of the work forgetting prevention device 6 side.

Next, the operation of the above embodiment will be described. The operation switch structure 45-1 integrated with the work forgetting prevention device 6 is attached to the press machine 1 by fixing it to the attachment site S of the press machine 1 which is a processing facility by the attachment unit 44.

When the door 2 provided on the front of the press 1 is closed, and the internal mechanism of the press 1 has an abnormality, the operation is not performed. The door open / close detector 4 does not output a signal,
The abnormality detector 5 does not output a signal (the abnormality lamp 3 is lit), and no signal is input to the door open / close detector 4 and the input terminals B and D connected to the abnormality detector 5. The other input terminals A, C, E, F, and G have working units A-1, C-1, and E, respectively.
Since the work at -1, F-1, and G-1 has been completed,
A signal indicating that the work has been completed is input.

In the line saving terminal device 72A,
A plurality of parallel signals input to the input terminals A to G via the connector 69 enter the link terminal 76 with a built-in connector on the transmission side, and the parallel signals are converted into serial signals by a parallel-serial converter. This serial signal enters the link terminal 77 with a built-in connector on the receiving side via the signal line 73, and is converted into seven parallel signals by the parallel-serial converter, and the PC
It is taken into the input unit 74 of 71.

Based on the signal received by the input unit 74, the CPU 72 outputs a command signal to the work forgetting prevention device 6, which is an output device. That is, the output unit 7
The plurality of parallel signals output from 5 are converted to serial signals by a parallel-serial converter in the line-saving terminal device 72B. The serial signal enters the receiving-side connector-equipped link terminal 77 via the signal line 73, is converted into a plurality of parallel signals by the parallel / serial converter, and is taken into the work forget prevention device 6 via the connector 67.

In the work forgetting prevention device 6, the work of the working units B-1 and D-1 in the press machine 1 is regarded as unworked and the signal state (no signal) and the working units A-1 and C-
The signal states (signaled) indicating that the operations at 1, E-1, F1-, and G-1 have been completed are respectively displayed on the display unit 68.
And the red light emitting diodes a to g are selectively lit. That is, the working units A-1, C-1, E-
1, the work in F-1, G-1 has been completed, and the work in the work units B-1, D-1 has not been performed, so that the red light emitting diodes a, c, e, g Light.

Further, since the buzzer 8 is added to the work forgetting prevention device 6, the work in the work sections B-1 and D-1 is in an unworked state. When a, c, e, and g are turned on and the operating lever 100 of the operation switch 12 is flipped (turned down), the buzzer 8 beeps and informs the operator that all the operations are not completed. This operation is repeated as long as the operation is not completed.

In the press 1, the door 2 provided on the front surface of the press 1 is open, and when there is no abnormality in the internal mechanism of the press 1, the door open / close detector 4
Output a signal, the abnormal light 3 is turned off, and the abnormal detector 5 outputs a signal. Therefore, all the working units A-1, B-
The work at 1, C-1, D-1, E-1, F1-, and G-1 becomes a signal state (signaled) as work completed.

In the line saving terminal device 72A,
A plurality of parallel signals input to the input terminals A to G via the connector 69 enter the link terminal 76 with a built-in connector on the transmission side, and the parallel signals are converted into serial signals by a parallel-serial converter. This serial signal enters the link terminal 77 with a built-in connector on the receiving side via the signal line 73, and is converted into seven parallel signals by the parallel-serial converter, and the PC
It is taken into the input unit 74 of 71.

Based on the signal received by the input unit 74, the CPU 72 outputs a command signal to the work forgetting prevention device 6, which is an output device. That is, the output unit 7
The plurality of parallel signals output from 5 are converted to serial signals by a parallel-serial converter in the line-saving terminal device 72B. The serial signal enters the receiving-side connector-equipped link terminal 77 via the signal line 73, is converted into a plurality of parallel signals by the parallel / serial converter, and is taken into the work forget prevention device 6 via the connector 67.

In the work forgetting prevention device 6, all the working units A-1, B-1, and C-
The signal state (signaled) indicating that the operations at 1, D-1, E-1, F1-, and G-1 have been completed is displayed by turning on all the red light emitting diodes a to g on the display unit 68. Is done. Then, the operation lever 100 of the operation switch 12
Is played, the buzzer 8 beeps continuously and informs the operator that all the work is completed. Note that the display 13 may count at the same time that the buzzer 8 beeps continuously.

It is to be noted that the transmission means may be a multi-wire for directly transmitting a parallel signal, which is a pickup signal generated by the work status detection means, to the input side of the work forgetting prevention device 6.

[0048]

As described above, according to the operation switch structure according to the first aspect of the present invention, an operation switch for issuing a start signal for starting the processing equipment when the operating lever is knocked down, and an operation switch for the processing equipment. A work forgetting device that detects the work situation of each work unit with a plurality of work situation detection means and activates the processing equipment only when all of the pickup signals generated by these work situation detection means are input is provided. Therefore, operability is good, and when used for starting processing equipment, etc., not only does starting error not occur,
When the operator knocks down the operating lever, the operation switch issues a start signal to activate the processing equipment, but only when all the work status detection means on the processing equipment side emits all the pickup signals for the work, prevents the work from being forgotten. The equipment can activate the processing equipment.

According to the operation switch structure according to the second aspect of the present invention, in the processing equipment control device according to the first aspect, the work forgetting prevention device sends a pickup signal generated by the work status detecting means to each of the devices. 2. The display device according to claim 1, further comprising a display unit for selectively lighting and displaying.
Not only can the same effect as the effect of the invention of the present invention be achieved, but also in the work forgetting prevention device, when any of the working units in the processing equipment is not working, the work situation detecting means picks up. In order to issue a pickup signal only for the work unit where the work has been completed without issuing a signal, only the lighting means corresponding to the work unit where the work has been completed is lit on the display unit, and the work has not been performed. The lighting means corresponding to the work unit is displayed so as not to light.
For this reason, it is possible to determine which of the working units in the processing facility is abnormal only by looking at the display unit.

According to a third aspect of the present invention, in the processing equipment control device according to the first or second aspect, the work forgetting prevention device operates the operating lever of the operation switch. In this case, by providing the sound means for notifying that all the work is not completed by an intermittent sound, not only the same effect as the effect of the above-described claim 1 or claim 2 can be obtained, When the operation forgetting prevention device operates the operating lever of the operation switch, the audio means can notify the intermittent sound that all the operations have not been completed. In particular, by combining with a display unit that is displayed as selective lighting, it is possible to more effectively determine which of the working units in the processing equipment is abnormal.

Further, according to the processing equipment control apparatus according to the fourth aspect of the present invention, a plurality of operation state detecting means for detecting the operation state of each working section of the processing equipment and generating a pickup signal, and the operating lever are knocked down. An operation switch for issuing a start signal for activating the processing equipment, a work forget prevention device having a work forget prevention function for operating only when all of the pickup signals issued by the work situation detection means are input, and the work situation A transmission means for transmitting a pickup signal generated by the detection means to the work forgetting prevention device, whereby an operator issues a start signal for activating the processing equipment by the operator turning down the operating lever by hand while walking. However, all the work situation detection means on the processing equipment side issued all the work pickup signals. If only, it is possible to work forgetting prevention device activates the processing equipment.

According to a fifth aspect of the present invention, in the processing equipment control device according to the fourth aspect, the transmission means transmits the parallel signal, which is a pickup signal generated by the work status detection means, to the parallel signal. A link terminal that converts one serial-to-serial converter into a serial signal, sends this serial signal to the other parallel-to-serial converter, converts it into a parallel signal, and transmits the parallel signal to the input side of the work-forgetting prevention device. Thereby, not only can the same effect as the effect of the invention of claim 4 be obtained,
The wiring space can be reduced by the link terminal.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment of a processing equipment control device provided with an operation switch device according to the present invention.

FIG. 2 is a perspective view of a basic configuration of the operation switch device according to the present invention.

FIG. 3 is an exploded perspective view of the operation switch device.

FIG. 4 is a side view of the operation switch device.

FIG. 5 is a partially sectional front view of an operation switch in the operation switch device.

FIG. 6 is an explanatory diagram of a configuration of a link terminal.

FIG. 7A is an explanatory diagram of a lighting display when there is no work in the display unit of the work forgetting prevention device. (2) is an explanatory diagram of a lighting display when all work is completed on the display unit of the work forgetting prevention device.

FIG. 8 is a perspective view of a part of a processing line using a conventional operation switch structure.

FIG. 9 is a perspective view of a conventional operation switch structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Press machine (processing equipment) 4 Door opening / closing detector (work situation detecting means) 5 Abnormality detector (work situation detecting means) 6 Work forgetting prevention equipment 12 Operation switch

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takashi Nakano 1005 Iwashiro, Kurayoshi City, Tottori Prefecture Omron Kurayoshi Co., Ltd. (72) Hiroyoshi Matsunaga, Inventor Omron Co., Ltd. 10 Hanazono Todocho, Ukyo-ku, Kyoto-shi, Kyoto

Claims (5)

[Claims] 1. An operation switch for issuing a start signal for activating a processing facility when an operating lever is knocked down, and a plurality of working status detecting means for detecting a working status of each working unit of the processing facility, and a plurality of working status detecting means. An operation switch structure comprising: a work forgetting prevention device that activates the processing equipment only when all pickup signals generated by the detection means are input. 2. The processing equipment control device according to claim 1, wherein the work forgetting prevention device has a display unit for selectively lighting and displaying a pickup signal generated by the work situation detecting means. 3. The sound processing device according to claim 1, wherein the work forgetting prevention device includes a sound unit for notifying that all work is not completed by an intermittent sound when the operation lever of the operation switch is operated. Item 3. The processing equipment control device according to Item 2. 4. A plurality of work condition detecting means for detecting a work state of each work unit of the processing equipment and issuing a pickup signal, and an operation switch for issuing a start signal for starting the processing equipment when an operating lever is knocked down. A work forgetting prevention device that activates the processing equipment only when all of the pickup signals generated by the work situation detecting means are input; and a transmission means that transmits a pickup signal generated by the work situation detecting means to the work forgetting prevention apparatus. A processing equipment control device comprising: 5. The transmission means converts a parallel signal, which is a pickup signal generated by the work status detection means, into a serial signal with one parallel-serial converter, and converts the serial signal to the other parallel-serial converter. 5. The processing equipment control device according to claim 4, wherein the link terminal is a link terminal that transmits the signal, converts the signal into a parallel signal, and transmits the signal to an input side of the work forgetting prevention device.