JP2003080528A - Method for diagnosing abnormality of ejector assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To diagnose the abnormality due to the too little load of the power transmission system of an ejector assembly and to easily specify an abnormal place to perceive trouble beforehand. SOLUTION: Trial operation is carried out to set not only the upper and lower limit values of the number of rotations of a servo motor but also the upper and lower limit values of the cycle time of a moving body. At the time of automatic operation, the number of rotations of the servo motor is detected to output a first alarm for reporting speed abnormality. When the detected value of the number of rotations is normal, the cycle time is detected after the servo motor is stopped and, when the detected value of the cycle time is not more than the lower limit value or not less than the upper limit value, a second alarm for reporting power transmission abnormality is outputted. In response to the second alarm, a candidate part causing power transmission abnormality is displayed along with the history data of the number of times and the cycle time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for diagnosing an abnormality in each part of a machine in a take-out machine for taking out various processed products from various processing machines.

[0002]

2. Description of the Related Art For example, a take-out machine for an injection molding machine is constructed so that a chuck is moved in and out of the molding machine, a resin molded product is taken out of a mold and taken out of the machine. Since this take-out machine operates by linking with the molding machine, an abnormality or failure of the take-out machine has a great influence on the operating rate of the molding machine. Therefore, conventionally, the number of revolutions of the motor provided in the chuck moving mechanism is monitored, and when the number of revolutions falls below the set value, the machine operation is stopped and an alarm indicating that there is an abnormality in the process is displayed. , A method to promote early recovery was adopted.

[0003]

However, the conventional abnormality diagnosis method has the following problems. (1) It is possible to diagnose abnormalities due to excessive load, such as seizure of guides and damage to bearings, but loose belts, broken shafts, etc.
An abnormality due to an underload of the power transmission system could not be diagnosed. (2) Although it is possible to specify in which process the abnormality has occurred, it is difficult to specify in which part of the process the abnormality has occurred. (3) In many cases, the parts were already damaged at the time of diagnosing the abnormality, and the failure could not be detected in advance.

An object of the present invention is to solve the above problems and provide an abnormality diagnosis method capable of diagnosing an abnormality due to an underload of a power transmission system of an unloader, easily identifying an abnormal portion and detecting a failure in advance. To do.

[0005]

In order to solve the above problems, an abnormality diagnosing method for a take-out machine according to the present invention is a take-out machine for taking out a processed product by moving a chuck inside and outside a machine.
The operation information of the actuator provided in the chuck moving mechanism and the operation time of the moving body driven by the actuator are detected, and each detected value is compared with a preset upper limit value and lower limit value. It is characterized in that the first alarm is generated when it is abnormal, and the second alarm is generated when the detected value of the operation information is normal and the detected value of the operation time is abnormal.

Here, in addition to the injection molding machine, the processing machine includes various machines such as a machine tool and a surface processing machine. The processed products include not only resin molded products but also various products or semi-finished products such as sheet metal molded products, machined products and surface processed products. The chuck for taking out the processed product is not particularly limited, and examples thereof include a device that sucks the processed product by vacuuming, a device that grips the processed product by opening and closing a claw, and the like.

The "chuck moving mechanism" is a mechanism for moving the chuck in and out of the processing machine. In the case of a take-out machine in which the chuck moves in a plurality of directions, a plurality of units provided in each direction are used. Abnormality diagnosis is performed in a required part or all of the moving mechanisms. Examples of the "actuator" of the chuck moving mechanism include a motor and an air cylinder. The "actuation information" of the actuator is information that specifies the speed and load of the actuator by the amount of electricity, and for example, detects the rotation speed of the motor with an encoder or detects the load torque of the motor from the current value. You can

The "moving body" driven by the actuator is a member of the elements constituting the chuck moving mechanism, which directly or indirectly supports the chuck and moves in a predetermined stroke (for example, linear movement or rotational movement). Is.
The "moving time" of the moving body is the time required for the moving body to move a predetermined distance, and for example, the cycle time from the start end of the stroke to the end thereof, the required time of the acceleration or deceleration section, the intermediate section The required time can be detected.

The "upper limit value and lower limit value" define a range in which the operation of the actuator or the moving body can be recognized as normal, and are set as electric quantity values which can be compared with the detected value of the operation information or the operation time. To be done. When setting each value, the operator can manually input based on the operating program and experience value of the processing machine, but the upper limit value and the lower limit value can be set in the point that the data suitable for the actual operating condition can be acquired. It is preferable to set based on the execution value of the trial operation.

"When the detected value of the operation information is abnormal" means that the speed or load of the actuator is below the lower limit value or above the upper limit value. At this time, the first value for notifying the speed abnormality or the load abnormality is given. 1 Alarm is output. "When the detected value of operation information is normal and the detected value of operating time is abnormal" means that the speed or load of the actuator is normal, but the operating time of the moving body is below the lower limit value or above the upper limit value. Yes, at this time, the second alarm for notifying the power transmission abnormality is output.

It is preferable to display a candidate part that is a factor of the power transmission abnormality in response to the second alarm so that the location of the power transmission abnormality can be specified in detail. In this case, when the detection value of the operation time is equal to or higher than the upper limit value, the candidate parts that cause the moving body to extend are displayed, and when the detected value is equal to or lower than the lower limit value, the candidate parts that cause the early arrival of the moving body are displayed. It may be displayed. Further, in response to the first alarm, a candidate component that causes a speed abnormality or load abnormality of the actuator may be displayed.

The abnormality diagnosis method of the present invention is characterized in that history of operation information and operation time is recorded and history data is displayed at any time in order to specify the abnormality in more detail. For example, the operation information and the operation time for the past several times or several hours are updated and recorded in the storage device, and when an abnormality occurs, it is displayed on the display device together with the candidate parts. Alternatively, only the peak value may be extracted from the detected values of the operation information and the operation time, and the long-term history data over the past several days or months may be recorded.

In this case, it is preferable to transmit the history data to a host computer at a remote place via a communication line so that the abnormality of the unloader can be diagnosed at the remote place. The transmission data may include not only history data but also control data such as various set values and communication data with the processing machine. Examples of the communication line include a local communication line using a LAN and a wide area communication line using the Internet. A mobile phone with a mail can also be used as the transmission / reception device.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is embodied in a take-out machine for an injection molding machine will be described below with reference to the drawings. As shown in FIG. 1, the main frame 2 of the take-out machine 1 is fixed on the injection molding machine 3 so as to extend in the left-right direction. The left-right moving body 4 is supported on the main frame 2, and the left-right moving body 4 has a sub-frame 5 long in the front-rear direction.
Is fixed. The front-back moving body 6 is supported by the sub-frame 5, and the up-down moving body 8 is supported by the front-back moving body 6. A revolving unit 9 is supported by the vertical moving unit 8 and a plurality of chucks 10 are mounted on the revolving unit 9. Then, the chuck 10 moves back and forth, up and down, and left and right to extract a resin molded product from the mold 11 of the molding machine 3 and take it out of the machine.

The mechanism for moving the chuck 10 in the front-rear direction includes a front-rear moving body 6, a guide 19 for guiding the front-rear moving body 6,
A servomotor 20 with a speed reducer for driving the front-rear moving body 6,
It is composed of a belt 21 that transmits the power of the servomotor 20 to the front-rear moving body 6. As shown in FIG. 2, the left-right moving mechanism of the chuck 10 includes a left-right moving body 4, a guide 13 for guiding the left-right moving body 4, a servomotor 14 with a speed reducer for driving the left-right moving body 4, and a servo. Motor 14
It is composed of a belt 15 and pulleys 16, 17 and 18 for transmitting the power of the above to the left and right moving body 4.

As shown in FIG. 3, the vertical moving mechanism of the chuck 10 employs a double speed mechanism for driving the vertical moving body 8 at high speed. The vertical moving body 8 is formed in a columnar shape, and is supported by the elevating body 23 via a guide 22. The lifting body 23 is supported by the front-rear moving body 6 via a guide 24,
It is driven by a servomotor 25 with a speed reducer via an end belt 26. The vertically movable endless belt 2 is provided on the lifting body 23.
7, a part on one side is connected to the front-rear moving body 6 by a joint 28, and a part on the other side is connected to the vertical moving body 8 by a joint 29. Then, the endless belt 27 is rotated by the movement of the lifting body 23, and the endless belt 27 is rotated.
The vertical moving body 8 is driven at a speed twice as fast as that of the elevating body 23 by the rotation.

A double speed mechanism using two actuators of a servo motor and an air cylinder may be adopted as a mechanism for moving the chuck 10 in the vertical direction. Chuck 10
In the turning mechanism, the turning body 9 is driven by the servomotor 30 (see FIG. 1). Guide 1 for each mechanism
LM guides (linear motion guides) using rolling guides are used for 3, 19, 22, 24, and belts 15, 21,
Toothed belts are used for 26 and 27. It is also possible to use chains or ball screws instead of belts.

The servomotors 14, 20, 25 of each mechanism,
30 is servo-controlled by the controller of the unloader 1.
For example, in the mechanism for moving the chuck 10 in the vertical direction, as shown in FIG.
The servo motor 25 is controlled at a predetermined speed via 2. Further, the control device 31 has a function of detecting the number of rotations of the servo motor 25 based on a signal from the encoder 33, and a timer function of detecting a cycle time from the stroke start end to the end of the vertical moving body 8. . Then, an input device 35 for inputting various setting values to the control device 31,
A storage device 36 for storing set values, detected values, etc., and a display device 37 for displaying stored data, alarms, etc. are connected.

The take-out machine 1 having the above-mentioned construction takes out the molded product in the order of steps shown in FIGS. During the molding operation of the molding machine 3, the chuck 10 stands by at the origin position O above the mold 11. When the molding machine 3 finishes one shot and a take-out start command is issued after the mold is opened, first, the vertical moving body 8 descends, the front-back moving body 6 advances, and the chuck 10 holds the molded product. Next, the front-rear moving body 6 retreats, the vertical moving body 8 rises to the origin position O, and the unloader 1 outputs a mold clamping start command to the molding machine 3. Subsequently, the left and right moving body 4 moves out of the machine, the swinging body 9 swings to change the direction of the chuck 10, and the up and down moving body 8 descends to move the chuck 10
Releases the molded article. Thereafter, (10) the vertical moving body 8 rises, (11) the swinging body 9 swings to restore the orientation of the chuck 10, (12) the horizontal moving body 4 moves into the machine, and the chuck 10 moves to the origin position O. Return to.

Next, a method of diagnosing the abnormality of the unloader 1 will be described. As shown in FIG. 7, when starting operation of the unloader 1, a trial operation (manual operation) for one cycle is executed (step S1). Here, each servo motor 14, 2
The rotation speed of 0, 25, 30 and the cycle time of each moving body 4, 6, 8, 9 are detected for each process, and the plus and minus allowable values are added to these execution values to rotate at the time of automatic operation. The upper limit value and the lower limit value of the number and the upper limit value and the lower limit value of the cycle time are set in the storage device 36 (step S2). By doing so, it is possible to automatically set the data suitable for the actual operating condition without inspecting each part at the start of operation. The upper limit value and the lower limit value may be set as a percentage of the execution value.

In the automatic operation, substantially the same diagnostic program is executed in each process (excluding the process of gripping and releasing the molded product). First, when the start command for the process is confirmed based on the end signal of the previous process (step S11), the timer is started (step S12), the servo motor 14,
20, 25, 30 are driven (step S13), and the moving bodies 4, 6, 8, 9 are moved in each direction. And FIG.
As shown in FIG. 5, when a preset time (exemplification of acceleration time) has elapsed from the start of the process (step S14), the rotation speeds of the servo motors 14, 20, 25, 30 are detected, and the detected values are stored in the storage device 36. It is stored (step S1
5).

Next, the detected value of the rotational speed is compared with the upper limit value and the lower limit value (step S16), and if the detected value is normal (lower limit value ≤ detected value ≤ upper limit value), the servomotors 14, 2
Drive of 0, 25, 30 is continued, rotation speed is monitored,
The detected value is updated and recorded in the storage device 36 as a history. When the moving bodies 4, 6, 8 and 9 reach the end of the stroke, the end command is confirmed based on the signal from the limit switch or the like (step S17), and the servo motor 1
4, 20, 25, 30 are stopped (step S18),
The timer is stopped (step S19). Then, the cycle times of the moving bodies 4, 6, 8, 9 are detected, and the detected values are updated and recorded as a history in the storage device 36 (step S20). Thereafter, the detected value of the cycle time is compared with the upper limit value and the lower limit value (step S21), and if the detected value is normal (lower limit value ≦ detected value ≦ upper limit value), a process end signal is output (step S22). .

On the other hand, when the detected value of the rotational speed is less than the lower limit value or more than the upper limit value, the servomotors 14, 20, 25, 3
A speed abnormality of 0 is diagnosed, and a first alarm for notifying this is output (step S23), and at the same time, a signal for stopping the operation of the unloader 1 is output (step S25). Then, in response to the first alarm, the candidate parts that cause the speed abnormality in the process are displayed on the display device 37. For example, as shown in FIG. 9, in the case of the chuck raising process, an excessive load is mainly generated in the inner and outer LM guides 22 and 24 (seizure), the reducer bearing (damage) of the servo motor 25, the belt cover (contact), and the like. A list of a plurality of candidate parts to be displayed is displayed together with the part number and the abnormality content.

Further, when the detected value of the rotational speed is normal and the detected value of the cycle time is below the lower limit value or above the upper limit value,
A power transmission abnormality of the moving mechanism is diagnosed, and a second alarm for notifying this is output (step S2).
4). Then, in response to the second alarm, the candidate parts that cause the power transmission abnormality in the process are displayed on the display device 37. For example, as shown in FIG. 10, in the case of the chuck raising process, the endless belt 26 and the endless belt 27 (jumping or loosening), the speed reducer shaft of the servomotor 25 (broken), its coupling (slip), etc. A plurality of candidate parts that cause an underload in the transmission system are displayed together with a part number and an abnormality content.

Therefore, the following operational effects can be obtained. (A) It is possible to accurately diagnose not only an abnormality due to an excessive load such as seizure of a guide or damage to a bearing, but also an abnormality due to an excessive load of a power transmission system such as a loose belt or a broken shaft. (B) From the two alarm display screens, it is possible to narrow down the parts level and identify in detail what kind of abnormality has occurred in what part of which process, and to specify it in detail and quickly, and shorten the time until recovery, that is, downtime. (C) By strictly setting the upper and lower limits,
Abnormalities can be detected before parts are damaged, and measures can be taken early to avoid failures. (D) As shown in FIG. 8, a speed abnormality can be diagnosed for a long time in a constant velocity section of a moving body.

As shown in FIGS. 9 and 10, the display device 3
7, an up scroll button 39 and a down scroll button 40 for displaying all candidate parts, a previous button 41 and a next button 42 for switching the screen, and a send button 43 for starting the send program. It is provided. Then, on the second alarm display screen, the next button 4
When 2 is pressed, as shown in FIG. 11, the history data for the set number of times executed in the past in the process is displayed. The history data includes dates, product numbers, rotation speed detection values, cycle time detection values, and the like, and is displayed in a list in order from the latest data.

Therefore, the following operational effects can be obtained. (E) When an abnormality occurs, the history data and the candidate parts on the previous screen can be compared to narrow down the abnormal part and the abnormal part in more detail. (F) Historical data is displayed at any time, changes in the number of revolutions and cycle time are collated, the life of parts can be predicted, and this is useful for pre-maintenance. (G) History data can be stored as technical data for new product development.

When the send button 43 is pressed, the send program is started and history data, various set values, and the molding machine 3 are pressed.
A diagnostic file containing the data necessary for a technician at a remote location to inspect the abnormality, such as communication data, is automatically created. Then, this file is transmitted by a transmission / reception device (not shown) attached to the unloader 1 through a premises or wide area communication line,
It is transmitted to a host computer at a remote place using a LAN or the Internet.

Therefore, the following operational effects can be obtained. (H) A user or a full-time technician of the manufacturer can diagnose the abnormality of the unloader in detail while being in a remote place. (I) It is not necessary for a manufacturer's full-time engineer to visit the site, and after-sales service costs can be saved. (J) Replacement parts or preparation parts can be quickly arranged according to the diagnosis result. (K) If a mobile phone with mail is used as the transmission / reception device, the unloader can be quickly restored regardless of where the dedicated engineer is. (L) The manufacturer can promptly deliver a new or modified program to the user by using this system when the production of a new molded product is started up or a program abnormality occurs.

The present invention is not limited to the above-described embodiment, but may be embodied with appropriate modifications within the scope not departing from the spirit of the invention, for example, as follows. (1) As shown in FIG. 12, the time (or distance) from the start of the process until the maximum load torque is generated is set, and when the set time has elapsed, the load torque of the servo motor is detected and the detected value is detected. By comparing with the upper limit value and the lower limit value, the load abnormality in the early stage of the process can be diagnosed. (2) Two detection points (time or distance) are set in the middle of the constant velocity section where the load torque is stable, the average value of the load torque in this section is calculated, and the average value is compared with the upper limit value and the lower limit value. By doing so, diagnose load abnormalities in the middle of the process. (3) The abnormality diagnosis method of the above embodiment is applied to a take-out machine that takes out various processed products from various processing machines such as a machine tool, a surface processing machine, a packaging machine, and a food processing machine.

[0031]

As described in detail above, according to the abnormality diagnosing method of the present invention, an abnormality due to an excessive load of the power transmission system can be diagnosed on the basis of the operation information of the actuator and the operation time of the moving body. You can easily identify the location,
It has an excellent effect of being able to detect a failure in advance.

[Brief description of drawings]

FIG. 1 is a perspective view showing an entire unloader in which an abnormality diagnosis method of the present invention is carried out.

FIG. 2 is a front view showing a lateral movement mechanism of a chuck in the take-out machine.

FIG. 3 is a front view showing a vertical movement mechanism of a chuck in the take-out machine.

FIG. 4 is a block diagram showing an abnormality diagnosis system for the unloader.

FIG. 5 is a process explanatory view of the same take-out machine.

FIG. 6 is a time chart showing the operation of the mobile body.

FIG. 7 is a flowchart showing an embodiment of an abnormality diagnosis method according to the present invention.

FIG. 8 is a speed characteristic diagram of a servo motor for supplementarily explaining the diagnostic method.

FIG. 9 is a front view of a display device showing a display screen of a first alarm.

FIG. 10 is a front view of a display device showing a display screen for a second alarm.

FIG. 11 is a front view of a display device showing a display screen of history data.

FIG. 12 is a load characteristic diagram of a servo motor showing a modification example of the abnormality diagnosis method.

[Explanation of symbols]

1 unloader 3 injection molding machine 4 left and right moving objects 6 Front-rear moving body 8 Vertical moving body 9 revolving structure 10 chuck 14 Servo motor 15 belts 19 Guide 20 Servo motor 21 belt 22 Guide 24 guides 25 Servo motor 26 Ended Belt 27 Endless belt 30 Servo motor 31 Control device 32 Servo control unit 33 encoder 35 input device 36 Storage 37 Display 43 Send button

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G05B 23/02 301 G05B 23/02 301X (72) Inventor Koji Nanasawa 3-Akita, Oguchi Town, Niwa District, Aichi Prefecture 133 Incorporated company Star Seiki (72) Inventor Shinichi Kakimoto 3-133 Akita, Oguchi-cho, Niwa-gun, Aichi Prefecture Incorporated Star Seiki (72) Inventor Tsutsugu Nakamoto 3-133 Akita, Oguchi-cho, Niwa-gun, Aichi Equity company Star Seiki (72) Inventor Keiji Matsunaga 3-133 Akita, Oguchi-machi, Niwa-gun, Aichi Stock Company Star Seiki (72) Inventor Yasushi Iwanari 3-133 Akita, Oguchi-cho, Aichi Prefecture Star Seiki ( 72) Inventor Atsushi Morikawa 3-133 Akita, Oguchi-machi, Niwa-gun, Aichi F-term inside Star Seiki Co., Ltd. (reference) 3C007 AS01 BS03 HS27 HT02 HT06 KS22 KS38 KV01 MS15 MS2 3 4F202 AM09 AP10 AP20 CA11 CA30 CB01 CM12 CS07 4F206 AM09 AP10 AP20 JA07 JL02 JN41 JP15 JP27 JQ90 5H223 AA06 DD03 DD07 EE05 EE06 EE29 FF08

Claims (5)

[Claims] 1. A take-out machine for moving a chuck in and out of a processing machine to take out a processed product, by detecting operation information of an actuator provided in a chuck moving mechanism and operation time of a moving body driven by the actuator. , Comparing each detected value with the preset upper and lower limit values, the first alarm is generated when the detected value of the operation information is abnormal, the detected value of the operation information is normal, and the detected value of the operation time is abnormal. A diagnosing method for an unloader, wherein a second alarm is generated when 2. The unloader abnormality diagnosis method according to claim 1, wherein the candidate parts that cause the power transmission abnormality are displayed in response to the second alarm. 3. The abnormality diagnosing method for the unloader according to claim 1, wherein the upper limit value and the lower limit value are set based on the execution values of the trial operation. 4. A history of operating information and operating time is recorded,
The unloader abnormality diagnosis method according to claim 1, 2 or 3, wherein the history data is displayed at any time. 5. The method for diagnosing an abnormal condition of a unloader according to claim 4, wherein the history data is transmitted to a host computer at a remote place via a communication line.