JPH0133279B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a press, and is a double valve monitor for monitoring the occurrence of problems in a clutch brake solenoid valve that transmits power for a press whose power source is supplied from both ends of a crankshaft system. .

BACKGROUND ART Conventionally, some presses have been provided with two motors as power sources and operated simultaneously to turn a crankshaft and move a slide up and down. The crankshaft is connected via a clutch brake solenoid valve to each fly oil rotated by the motor. Of course, there is no problem when both solenoid valves are working normally.

However, in the unlikely event that the solenoid of the solenoid is disconnected, the solenoid valve itself is inconvenient due to an inconvenient poppet, or a failure occurs in the wiring system for excitation of this solenoid valve, a problem occurs with one of the clutch brake solenoid valves. As a result, the clutch brake on the normal side becomes overloaded, causing lining wear and heat generation, accelerating deterioration, and causing accidents due to eccentric loads.

Solenoid valves are generally equipped with a limit switch that operates and sends a signal to the outside when an inconvenience occurs, or a limit switch that operates and sends a signal to the outside each time the solenoid valve is energized and the poppet moves. I am trying to incorporate it.
Signals issued by these limit switches are used to detect inconveniences and malfunctions.

However, abnormalities may occur due to welding of the contacts of the internally incorporated limit switch, short-circuiting of the connection terminal to the limit switch to the non-safe side, etc. Therefore, this abnormality check must be performed, but since the abnormality check normally constitutes an external circuit, it is only necessary to perform a manual test first. Therefore, it is not possible to check for inconveniences that may occur during subsequent operations.

In a press, especially in a press that has power sources on both sides, it is extremely important to check the solenoid valve when the clutch is engaged or disengaged. It wasn't like that.

Purpose of the Invention The present invention has been made in consideration of the above, and is a double press that automatically checks the solenoid valve when the clutch is engaged or disengaged, and can stop the press operation in the event of an abnormality. To provide a valve monitor.

SUMMARY OF THE INVENTION The present invention uses a limit switch built into the clutch brake solenoid valve, so that these solenoid valves operate together, and when both are disconnected, they are always in an operating state, and a timer that is activated when a deviation occurs, such as a delay in the operation of one of them. is provided, and when this timer expires, an auxiliary relay turns off the power to the solenoid valve of the clutch brake, stopping the operation of the press.

Embodiment FIG. 1 is a circuit diagram of an embodiment of the present invention, in which lines 1 and 2 are connected to a press operation circuit and an operation circuit voltage is applied. 3 and 4 are double-valve solenoid valves with an operation confirmation limit switch provided corresponding to one clutch brake, and 5 and 6 are double-valve solenoid valves with an operation confirmation limit switch provided corresponding to the other clutch brake. When each solenoid valve 3, 4, 5, 6 is operating, the normally open contacts 3a, 4a, 5a, 6a of the limit switch of each solenoid valve 3, 4, 5, 6 are turned on and the normally closed contact is turned on. 3b, 4b, 5b, 6b are turned off, and when each solenoid valve 3, 4, 5, 6 is inoperative, the normally open contacts 3a, 4a, 5a, 6a are all turned off, and the normally closed contacts 3b, 4b, 5b are turned off. , 6b are both turned on. A normally closed contact 3b of the limit switch of the solenoid valve 3 and a normally closed contact 4b of the limit switch of the solenoid valve 4 are connected in series with a B contact 7b of a first auxiliary relay 7, which will be described later. A normally open contact 3a of the limit switch of the solenoid valve 3 is connected in parallel to this series circuit.
A series circuit of the A contact 7a of the first auxiliary relay 7 and the normally open contact 4a of the limit switch of the solenoid valve 4 is connected. This circuit is a circuit for solenoid valves 3 and 4 of one clutch brake, and a similar circuit for the other solenoid valves 5 and 6 is connected in series with this circuit, and an off-delay timer 8 is connected in series with these circuits. . The off-delay timer 8 eventually causes both clutch brake solenoid valves 3 to 6 to operate together.
The connection is such that excitation is continued when the device is inactive, and excitation is cut off when the device is out of operation. A second auxiliary relay 10 is connected to the power supply through a series circuit between the A contact 8a of the timer 8 and a normally open set button 9 that is manually opened and closed, and the second auxiliary relay 10 operates. The lamp 1 is held by the contact 10a, and the lamp 1 is held by the contact 10b.
1 is connected so that it lights up. The electromagnetic valves 3 to 6 and the first auxiliary relay 7 are connected to a known press operation command circuit via a normally open contact 10c of the second auxiliary relay 10.

Timer 8 is used to obtain stabilization time for discontinuities during limit switch switching and chattering during solenoid valve operation, and is normally set to about 500 ms.

Note that the A contact means a normally open contact that is turned on when energized and turned off when energized, and the B contact means a normally closed contact that is turned on when energized and turned off when energized.

The operation of the embodiment having the above configuration will be explained below. First, turn on the power to the press's operating circuit. At this time, all solenoid valves are not energized.
Therefore, the first relay 7 is also not energized. That is, all of the limit switches 3b, 4b, 5b, 6b and the contact 7b of the relay 7 are in the on state,
Timer 8 operates. Therefore, the A contact 8a is on. Therefore, when the set button 9 is pressed, the second relay 10 is energized and self-holds. At the same time, the lamp 11 is turned on. This second relay 1
0 excitation turns on the contact 10c,
When a press operation command is received, each solenoid valve is energized.
Both clutch brakes operate. At the same time the first
The auxiliary relay 7 is energized, the contact 7b is turned off, and the contact 7a is turned on. As described above, when each solenoid valve is energized and operated, the normally closed contact of each limit switch is turned off and the normally open contact of each limit switch is turned on. Therefore, timer 8 remains energized. In this way, the timer 8 remains energized as long as the press is operating normally.

Now, if for some reason the timing of the operations between the limit switches is out of order, the timer 8 will no longer be energized and the second auxiliary relay 10 will no longer be energized. Therefore, the power to the solenoid valves 3 to 6 and the first auxiliary relay 7 is cut off, the clutch is disengaged, and the operation is stopped.

There are various causes for this, such as broken coils of each solenoid valve, energization of only one side due to a problem with the connection wiring, the limit switch not working due to a problem with the poppet of the solenoid valve, and even the occurrence of welding of the limit switch contacts. etc. In either case, it is possible to detect each operation of the solenoid valve, stop the press operation, and notify.

Effects of the Invention As described above, according to the present invention, the operation of the press can be immediately stopped when a problem occurs in any one of the two pairs of double-valve solenoid valves that control the two clutch brakes. Therefore, the user can drive with peace of mind.

[Brief explanation of drawings]

FIG. 1 is an electrical circuit diagram of an embodiment of the present invention. 1, 2...Line, 3-6...Solenoid valve, 7...
1st auxiliary relay, 8... timer, 9... set button, 10... second auxiliary relay.

Claims (1)

[Claims] 1 Clutch brakes are provided at both ends of the crankshaft, and both ends of the crankshaft are connected to separate power sources via each clutch brake, and each clutch brake is provided with a double-valve solenoid valve with an operation check limit switch. In the monitor of the double valve of the press installed, the series circuit of the normally open contact of the double valve solenoid valve provided corresponding to one clutch brake and the normally open contact of the first auxiliary relay, as well as the series circuit of these normally closed contacts. A parallel circuit with the circuit, a series circuit of the normally open contacts of the double valve solenoid valve provided corresponding to the other clutch brake, and a series circuit of the normally open contacts of the first auxiliary relay, as well as a series circuit of these normally closed contacts. a parallel circuit, an off-delay timer connected to a power supply through a circuit in which both of the parallel circuits are connected in series, a normally open contact of this off-delay timer, and a normally open set button that is manually operated to open and close. a second auxiliary relay having a self-holding function connected to the power supply through a series circuit of the second auxiliary relay, and a normally open contact of the second auxiliary relay connected to each of the double-valve solenoid valves and the first auxiliary relay. A double valve monitor characterized by each being connected in series to the power supply circuit.