JPH0244608B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device for controlling a transfer feed in a transfer press.

(Conventional technology) A transfer press has multiple molds lined up in a straight line, and the material to be processed is sequentially fed from each mold to the adjacent mold in each process using a transfer feed, and each mold partially It is now processed into a final product using a mold at the final stage.

The transfer feed is composed of two parallel feed bars centered around a mold, and fingers provided on the feed bars in correspondence with the mold. The fingers are provided in pairs so as to face both feed bars, and are configured to grip the material in the mold and move it to the mold of the next stage in response to the operation of the feed bars. Therefore, the workpiece is gripped by the fingers (clamped) and carried by the action of the feed bar to the next mold position, where it is released (unclamped) and placed in that mold.

Although this operation is performed continuously, the fingers may fail to grasp the workpiece, which is a so-called misgrip. Therefore, in the transfer feed, each finger is provided with a detector (for example, a clamp detector) for detecting the workpiece, that is, for detecting whether the workpiece is properly gripped. If the workpiece is not reliably gripped by the fingers, the detector outputs a signal indicating a misgrip, and this signal is used to control the press (for example, to stop the press operation).

When a detector is used to detect the presence or absence of a material to be processed and the press is controlled using the signal, the press operation is generally stopped immediately upon receiving a signal of a misgrip. However, assuming that the processed material is damaged during the process and cannot be passed on to the next process, the above method will not allow the press operation to be resumed.

The one that solved this situation was the Special Public Service of 1974.
This is disclosed in the invention of Publication No. 23473. What is shown here is a system (commonly known as intermittent operation or tooth extraction operation) that allows the press to continue operating without the workpiece in only that part when the workpiece is missing.

In the above conventional technology, it is determined whether or not there is a material to be processed in the previous stage, and when it is determined that there is no material to be processed, the detector of the stage concerned does not detect a misgrip, and the information on the absence of material is transferred to the next stage. It is configured to be sent to a stage and press operation is performed. In other words, while sequentially transmitting information that processing material is missing to subsequent stages,
At the stage where the information that there is no material is reported, the press continues to operate without determining whether there was a misgrip or not.

By the way, when such intermittent operation is performed, a new problem arises if the detector breaks down. For example, if the detector in the first stage fails, information indicating that there is no material is sent to the second stage even if there is material to be processed.
That is, when the second stage receives information that there is no material, the second stage determines that there is no material to be processed in the first stage. Therefore, in the second stage, the press operation is performed without determining the misgrip, and the information that there is no material to be processed is transmitted to the next stage.

As mentioned above, since the detector is malfunctioning in the first stage, the information that there is no material is transmitted to the second stage, so in the next process, there will be a misgrip in the second and third stages. will not judge. In this way, the number of stages in which a misgrip is not judged increases in each process, and eventually all stages are not judged to be a misgrip. This is extremely dangerous and will result in the same result as if no detector was installed.

(Problems to be Solved by the Invention) The present invention provides a transfer feed monitor that checks the operating status of a detector that detects that a workpiece is clamped, and correctly transmits information on the presence or absence of workpiece to the next stage. The objective is to provide a device.

(Means for Solving the Problems) The present invention includes a misgrip detection circuit that notifies the detector when the detector does not operate in a state where the information that there is a material to be processed is transmitted from the previous stage, and The present invention is characterized in that a failure detection circuit is provided to notify when the detector operates while information indicating that there is no material is transmitted.

(Operation) The previous stage determines whether or not there is material to be processed and notifies the next stage of this information. If there is material available, it will check for misgrips and notify you when you misgrip. If it is determined that there is no processing material in the previous stage (including when there is actually no processing material or when the detector is malfunctioning),
It does not judge whether there is a misgrip, but notifies you when the failure detection circuit is activated.

The fact that the detector is activated means that there is a workpiece on that stage, and at the same time it means that there was a workpiece on the previous stage. However, the information that there is no processing material is transmitted from the previous stage. This simply means that the previous stage detector is out of order. Naturally, if the detector does not operate at the stage where the information that there is no processing material is transmitted, the failure detection circuit will not operate, and so-called intermittent operation will continue without determining whether there is a misgrip.

(Example) FIG. 1 is a plan view showing the processed material conveyance portion of the feed bar, and shows that there are five stages No. 1 to No. 5. Clamp confirmation switches LS1 to LS5 are installed on the finger 2 of the feed bar 1 as a detector to detect the presence or absence of the processing material 3.
are provided for each. The contact point of this switch is indicated by ls2 (only the second stage is shown) in FIG. Needless to say, a and b attached to the contact display mean an a contact and a b contact.

Figure 2 shows the rotary cam switch RS of the press.
1 to RS4, each switch is set to turn on in the shaded area corresponding to the crank angle of the press. RS2 and RS3 are for communicating the presence or absence of material to the subsequent stage, and these contacts are represented by contact X1 in FIG. 4. Contact point X (not shown) occurs when there is processing material on the previous stage.
1 relay is activated, and when there is no relay, it is deactivated. In FIG. 4, the contacts X1 are all b contacts, so the contacts are off when there is material to be processed, and on when there is no material to be processed. Also, switch
The contact points of RS1 and RS4 are shown as rs1 and rs4 in Fig. 4.

FIG. 3 shows a part of the panel of the device of this embodiment,
A monitor switch SS1, an abnormality display lamp PL, and a reset switch SS2 are provided. An error indicator lamp PL and monitor switch SS1 are provided for each stage (others are omitted).
There is one reset switch SS2 in total.

The monitor switch SS1 is a three-notch switch that can take three states: monitor on, monitor off, and stage off. Monitor off does not detect misgrip and does not perform the operation of the present invention. The contact point of this switch is indicated by X0 in FIG. It turns on when the monitor is on and turns off when the stage is off. Note that the stage off is a stage where no mold is installed, and the contact X0 is used with the contact X0 turned off.

The contacts of the reset switch SS2 are indicated by X2 in FIG.

The circuit configuration of each of the above contacts is shown in FIG. Each contact is connected as shown in the figure, and operates the relays RY1, RY2, RY3 and lamp PL connected to each contact. In the figure, contact X1 is short-circuited *1 in a stage that cannot receive information from the previous stage, for example, only the first stage is connected, and in that stage *2 is also disconnected. In other stages this is reversed. In other words, *2 is connected, *
1 is not connected.

The circuit shown in FIG. 4 (in the case of the second stage) will be explained below. The switch RS1 turns off at a crank angle of 305 to 55 degrees, and the switch RS2 turns off.
operates when the crank angle is between 285 and 240 degrees.

Monitor switch SS1 is used with the monitor on, so contact X0 is on. First, reset switch SS2 is turned on to operate relay RY1, and its contact ry1a is used to hold the relay RY1. In this embodiment, an abnormality occurs when the relay RY1 changes from an operating state to an inactive state, and this is notified and the press is brought to an emergency stop.

When there is processing material on the previous stage, contact X1
is off. Now, if the press is moving from the bottom dead center to the top dead center, the contacts rs1, rs4, and ls2b are on, so the relay RY1 will not be on. Even if the crank angle reaches 240℃ and the processing material is grabbed and ls2b is turned off, the contact
Relay RY1 remains on with rs1 and rs4. Furthermore, even if contact rs1 turns on when the temperature reaches 305°, contact ls2a is turned on this time, so relay RY1
does not turn off. However, if you fail to grasp the processing material, ls2a and ls2b will not change, so contact rs
1 turns off, relay RY1 turns off. That is, if information indicating that there is a material to be processed has been transmitted from the previous stage, a misgrip is simply determined based on contacts rs1 and ls2a.

Next, when there is no material to be processed in the previous stage, the first stage, the contact X1 closes as shown. Therefore, when ls2b is turned on, that is, when the workpiece is gripped, contact rs1b returns and turns on at a crank angle of 305 degrees, so that relay RY3 operates. Therefore, the contact ry3b connected in series to the relay RY1 is turned off, and the relay RY1 is turned off, instructing an emergency stop of the press, and at the same time turning off the lamp PL.

In this way, in this embodiment, if a material to be processed is grabbed even though the information that there is no material to be processed has been transmitted from the previous stage, this is determined to be abnormal.

Note that the relay RY2 in the figure is activated when the stage that has been turned off grabs a workpiece, that is, when the setting of the clamp confirmation switch is incorrect.

(Effects of the Invention) As described above, the present invention makes a normal misgrip judgment when the information that processing material is present is transmitted from the previous stage, and at the same time, the switch that judges the presence or absence of processing material in the previous stage malfunctions. When something is wrong, it can notify you of the abnormality. Therefore, it is possible to prevent the inability to judge a misgrip during so-called intermittent operation, and it is possible to perform safe press operation.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the processing material conveyance section of the feed bar, Fig. 2 is a view showing the operation timing of the rotary cam switch, Fig. 3 is a front view of a part of the operation panel section, and Fig. 4 is a plan view showing the processing material conveying part of the feed bar. It is a circuit diagram of an example. 1...Feed bar, 2...Finger, 3...
...Machining material, LS2...Clamp confirmation switch,
ls2... Clamp confirmation switch contact, X0...
Monitor switch contact, X1...Previous stage information contact, RS1, RS4...Rotary cam switch, rs1, rs4...Rotary cam switch contact, RY1, RY3...Relay.

Claims (1)

[Claims] 1 In a system where multiple stages are arranged to install molds and press the processed material, each stage grips the processed material with its fingers and sends it to the subsequent stage. A detector that detects when a workpiece is clamped, a misgrip detection circuit that notifies the next stage when the detector at the next stage does not operate even though information that there is a workpiece has been transmitted from the previous stage, and 1. A feed monitor device for a transfer press, comprising a failure detection circuit that notifies when a detector in the next stage operates while information that there is no processing material is transmitted from the stage.