JPS5924440Y2 - Warning device for preventing raw materials - Google Patents

Description

[Detailed description of the invention] This invention is a machine tool that can automatically process a workpiece by turning on a start switch after mounting the workpiece. This invention relates to a warning device for preventing processing.

Considering the process of machining a workpiece that requires a lot of machining using an automatic machine tool in a factory, the worker generally removes the machined workpiece from the machine tool, installs a new unprocessed workpiece, and then Press the start switch of the machine tool to operate the machine tool automatically and process the workpiece, while
This is done by an operator transporting the processed workpiece to the next process while the machine tool is operating.

Therefore, workers often do not check whether the machine tool is operating normally, or forget to press the start switch, or press the start switch but the machine tool does not start machining because the conditions for starting are not met. If the operator fails to do so, the workpiece remains unprocessed, and if the operator does not notice this, the unprocessed workpiece will flow to the next process.

Such unprocessed workpieces must be eliminated because they increase the defective rate of the product, but conventional measures to prevent unprocessed workpieces include attaching so-called "bakayoke" to the machined part of processed workpieces, They also installed measuring equipment.

``Bakayoke'' may not be installed on some machines, and may be difficult for workers to understand.

Furthermore, there are restrictions on the machines on which the inspection device can be installed, and
It also requires space and is expensive.

The present invention was developed in view of these points, and is an inexpensive method that can warn the operator when a machine tool does not process a workpiece and prevent the occurrence of unprocessed workpieces. The purpose is to provide an applicable alarm device for preventing raw processing.

In order to explain the outline of the operation of an automatic machine tool, which is used to explain one embodiment of the present invention, as an example only, Fig. 1 is a schematic diagram for explanation, and Fig. 2 is a cycle diagram. It is shown.

When the automatic machine tool finishes machining the workpiece and all mechanisms are in the state before machine tool operation (hereinafter referred to as the original position),
When installing a workpiece on a machine tool, the operator removes the processed workpiece 2 from the table 1 and installs a new unprocessed workpiece.

After that, when the start switch 3 is pressed, the clamp device 4
operates and clamps work 2 (jig tightening).

When it is confirmed that the clamping device 4 has clamped the workpiece 2, a processing unit advance command is issued, and the processing unit 5 advances toward the workpiece 2 and processes the workpiece 2.

When the machining of the workpiece 2 is completed, the machining unit 1-5 will be described later, the clamping device 4 removes the clamp of the workpiece 2 (loosening the jig), and the machine tool returns to its original position.

The present invention relates to an alarm device for preventing workpieces from being left unprocessed, which is attached to the electric circuit of such an automatic machine tool.The present invention will be described below with reference to the drawings.

FIG. 3 is an electrical circuit diagram (sequence circuit diagram) showing one embodiment of the present invention.

Limit switch LS-L relays CR1, CR2, contacts CR1a, CR2a, 7a constitute means for detecting and storing the removal of a machined workpiece when the machine tool is in its original position.

The limit switch LS=1 is a switch that detects the presence or absence of the workpiece 2.The workpiece mounting shown in Fig. 1 is provided on the table 1, and is biased (ON) by mounting the workpiece 2.
It is supposed to be done.

Relay CRI has contacts CR1a to CR1c, is connected to a power supply line via limit switch LS-1, and is excited by energization of limit switch LS-1.

The relay CR2 is a relay that stores the removal of the workpiece 2, and has contacts CR2a to CR2c, and contacts 7a and CRla.
, g to the power supply line.

Self-holding contact CR2a is parallel to contact 7a and CRla.
is connected.

7a and 7b are relays (not shown in the drawing) that are energized when the machine tool is in its original position.

) is the contact point. The timer TRI is a timer that counts a certain period of time that is activated when a new workpiece is attached after the relay CR2 has memorized the removal of a processed workpiece, and includes contacts CRI b, CR2b, the alarm stop switch 10, and the above-mentioned contacts. It is connected to the power supply line via 8.

As shown in Fig. 2, the setting time of this timer is set at an appropriate time after the operator attaches the workpiece and until he presses the electromotive switch 3, after the machine tool starts operating, and when the machining unit 5 starts operating. It is set to be slightly longer than the time required to enter forward motion.

Relay CR3, buzzer BZI, timer contact TR1a,
Contacts CR3a, CR4c, CR5c are timer TRI
This is an alarm means that issues an alarm by operating for a certain period of time, or by turning on the start switch 3 when the inhibiting means described later is in the inhibited state.

Relay CR3 and buzzer BZI are connected to a line via timer contact TR1a and contact CR2b, and contact CR4, respectively.
c, a line via CR5c, and a line via self-holding contact CR3a of relay CR3.

The contact point 8 described above is a relay (not shown in the drawings) that is energized when issuing a forward command to the processing unit after the machine tool is started.

), and when the machine tool starts machining, the workpiece removal memory means (relay CR2) and timer TR
This constitutes means for returning based on 1.

Relay CR4 is a relay that is excited by pressing start switch 3, and has contacts CR4a to CR4c.

Relay CR5, contact CRIc, CR2c, 7 b
, CR4a, CR5a, g, etc. are means for prohibiting the starting of the machine tool when the starting conditions for the machine tool are not met.

Relay CR5 has contacts CR5a-CR5c,
Contacts CR1c, CR2C, 7b, contact C connected in parallel
It is connected via R4a, CR5a, and contact 9 to an operation completion line that is a power supply line.

Contact 9 is a relay (not shown in the drawing) that is energized when automatic cycle conditions are met.

) is the contact point. The automatic cycle conditions include conditions such as the presence of lubricating oil for the machine and the completion of clamp release by the clamp device 4.

Relay CR6 is a relay that is turned on when the machine tool is operated automatically.

The apparatus configured as described above operates as follows to warn the operator that the machine tool does not operate or has not operated, thereby preventing the workpiece from being left unprocessed.

When the machine tool has finished machining the workpiece and is in its original position, the machined workpiece energizes the limit switch LS1 and closes it, so relay CR1 is in the energized state, while relay CR2 is in the neutral state as described later. It is in an excited state.

When the operator removes the processed work in this state, the limit switch LS-1 is opened and the relay CRI is de-energized.

As a result, relay CR2 is energized via normally closed contact 8, CRla, and contact 7a, which is closed in the original position, and at the same time, self-holding contact CR2a is closed, so relay CR2 self-holds the energization. and remembers that the processed workpiece has been removed.

Next, when the operator attaches a new unprocessed workpiece, limit switch LS=1 is closed and relay CRI is energized.

As a result, contact CR1a is opened, but relay CR2 maintains its self-holding state as described above.

Therefore, contact CR2b is closed, and contact CR1b is also closed due to the excitation of relay CRI, so timer TR
I is connected to the power supply line via contacts CRI b, CR2b, switch 10, and contact 8 to start operation.

Now, after the workpiece is attached, when the operator presses the start switch 3 within a suitable time, the machine tool is started and a processing unit advance command is issued, but at this time the normally closed contact 8 is opened.

As a result, the self-holding of the excitation of relay CR2 is released,
Since relay CR2 is de-energized and contacts CR2b are opened, timer TRI is also reset and no longer operates.

On the other hand, if the operator forgets to press the start switch 3, the machine tool will not start, so the machining unit advance command will not be issued, and therefore the contact 8 will not be opened.

Therefore, the timer TR1 continues to operate and closes its contact TR1a after a certain period of time has elapsed.

As a result, relay CR3 is connected to the power supply line via contacts TR1a, CR2b, switch 10, and contact 8 and is excited, and at the same time, self-holding contact CR3a is closed to self-hold the magnetization.

As a result, the buzzer BZl connects contact CR3a and switch 10.
, is connected to the power supply line via the contact point 8, and emits an alarm sound to warn the operator that the start switch 3 has not been pressed after a certain period of time has elapsed.

Further, when the start switch 3 is pressed but the processing unit advance command is not issued because the clamp device 4 has caused a clamp failure, the buzzer BZI operates in the same manner and emits an alarm after a certain period of time has elapsed.

To stop the alarm sound of the buzzer BZI, press the alarm stop switch 10 to disconnect the timer TRI and relay CR3 from the power line, restore the timer TRI, and release the self-holding of the excitation of the relay CR3.

Next, when the machine tool is in its original position, the machined workpiece is being replaced, and the automatic cycle conditions described above are in place, the machine tool startup conditions are met.
Contacts CRI c, CR2c, 7 b.

9 is closed, relay CR5 is energized, which closes solenoid contacts CR5a and CR5b and opens CR5c. Therefore, by closing starting switch 3, the machine tool starts automatic operation.

On the other hand, if these starting conditions are not met, contacts CR1c,
Since any one of the contacts CR2c, 7b, and 9 opens, relay CR5 becomes de-energized, and contact C
Open R5b and prohibit automatic driving.

At this time, contact CR5c is closed, so when the operator turns on the start switch 3, relay CR4 is energized and closes contact CR4C, and as a result, relay CR3 and buzzer BZI are activated via contacts CR5c and CR4c. The alarm is connected to the power supply line to emit an alarm sound, and this state is maintained by closing CR3.

As a result, the operator is warned that the machine tool will not start at the same time as the start switch 3 is pressed, and it is possible to prevent unprocessed workpieces from being overlooked.

Note that the contacts CR1C and CR2c are for prohibiting automatic operation of the machine tool when the machined workpiece is not replaced, and can prevent the machined workpiece from being machined twice.

In this way, the present invention issues an alarm after a certain period of time if the operator forgets to press the start switch on the machine tool, or if the start switch is pressed but machining is not performed due to a clamp failure in the clamping device. In addition, if the start switch is pressed when the machine tool cannot be started, an alarm is immediately issued to warn the operator that the workpiece will not be processed and prevent unprocessed workpieces from flowing to the next process. This can reduce the rate of defective products.

Furthermore, since the device according to the present invention can be obtained with a simple configuration, it is much cheaper than inspection devices and the like, and can be applied to any machine tool.

Furthermore, issuing a warning to the worker with a buzzer sound as in the example can definitely call the worker's attention, and this kind of countermeasure to prevent unprocessed material has never existed before and is useful. There is something.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram for explanation, Figure 2 is a cycle diagram,
FIG. 3 is an electrical circuit diagram showing an embodiment of the present invention. 3...Start switch, CRI~CR6...Song relay, LS-1...Limit switch, TR1
・・Song timer, BZl・・・・Buzzer

Claims (1)

[Scope of Claim for Utility Model Registration] In a machine tool that can automatically process a workpiece by turning on a start switch after attaching the workpiece, means for detecting and storing removal of a processed workpiece; a timer for instructing a certain period of time to be activated by installing a new workpiece after memorizing the removal of a processed workpiece; and means for returning based on the storage means and the timer when the machine tool starts machining. , means for prohibiting the start of the machine tool when start conditions are not met, such as the machine tool being in its original position, a workpiece being replaced, and automatic cycle conditions being met; and a means for prohibiting the start of the machine tool for a certain period of time. 1. An alarm device for preventing unprocessed parts, comprising an alarm means that issues an alarm when activated or when the start switch is turned on when the prohibition means is in a prohibited state.