JPH0724955B2 - Press machine controller - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a control device for a press machine which is provided with noise prevention measures.

BACKGROUND ART OF THE INVENTION AND PROBLEMS THEREOF The press machine generates a large noise of about 100 to 110 horns during its operation.

Conventionally, in order to protect the environment from this kind of noise, measures have been taken such as providing a soundproof wall on the press machine itself or in the vicinity of the factory, prohibiting nighttime work altogether.

However, when the soundproof wall is attached to the press machine itself, the workability of the press machine becomes poor. Further, when a soundproof wall is provided around the factory, noise countermeasures around the factory can be taken, but it is difficult to take noise countermeasures inside the factory. Moreover, the production of these soundproof habits requires a considerable amount of cost. Moreover, productivity is significantly reduced if work at night is totally prohibited.

[Object of the Invention] In view of the above problems, an object of the present invention is to provide a control device for a press machine, which can reduce the noise of the press machine as much as possible and improve the productivity.

SUMMARY OF THE INVENTION In order to achieve the above object, in the present invention, a main flywheel and a sub flywheel are provided in a press machine, and a control device of the press machine sets a ram speed for setting a ram speed of the press machine. A processing unit, a motor drive power supply device having an inverter, a motor control unit for controlling the motor drive power supply device, a clutch brake of the main flywheel, and a clutch for connecting and disconnecting the main flywheel and the sub flywheel. The press control unit for controlling the ram speed and the operation panel for setting the ram speed, which includes the clock operation key, the speed setting key and the time display, are used to appropriately and appropriately reduce the ram speed.

[Embodiment of the Invention] An embodiment in which the control device according to the present invention is applied to a crank press will be described with reference to Figs.

FIG. 1 is an explanatory view showing an outline of a crank press as an example of a press machine equipped with a control device according to an embodiment of the present invention.

The crank press 1 has a frame 3 and a rotatable crank shaft 9 above a die 7 fixed on a bolster 5. A ram 13 having a punch 11 is attached to a crank portion 9a of the shaft 9 so as to be vertically movable as the crank shaft 9 rotates. The crankshaft 9 is provided with a disk 15 for detecting the rotational position of the shaft 9 or the vertical position of the ram 13, and a dog 15a is provided at a predetermined position of the disk 15. Further, on the frame 3 side, a limit switch 17 for detecting the dog 15a at a position where the ram 13 comes before the top dead center is provided.

On the other hand, a main flywheel 21 is provided on the crankshaft 9 via a clutch brake 19, and the flywheel 21 is rotationally driven by driving a pulley 23 provided on a side surface thereof with a belt 25. It has become so.
The belt 25 is driven by a pulley 29 of a speed reducer 27 driven by a three-phase motor M.

Further, in this example, in particular, a sub flywheel 33 is provided on the side surface of the main flywheel 21 via a clutch 31. The clutch 31 is operated (turned on) when the motor M is rotated at a low speed, and at this time, the clutch 31 cooperates with the main flywheel to compensate for the decrease in the kinetic energy of the main flywheel.

The motor M is driven by the motor drive power supply 35, and this power supply
The 35 is configured so that its frequency can be changed by using an inverter, as described in detail in FIG.

The control device 37 has an operation panel 39, on which the LC
D display 41, clock operation keys 43a, 43b, 43c, 43d, and speed setting keys 47a to 47e equipped with LED displays 45a to 45e, respectively
And are provided.

The LCD display 41 normally displays the current time, and displays the set time based on a predetermined operation when setting the ram speed.

The operation method of the clock operation keys 43a, 43b, 43c, 43d is as follows. That is, when the key 43c is pressed once, the LCD display 41
Stops displaying the current time and stops at that time. Next, if the key 43a is continuously pressed, the display time of the LCD display 41 rapidly advances. Continuing to press the key 43b, on the contrary, it rapidly retreats. When these keys 43a and 43b are momentarily operated, the display of the display 41 on the LCD is advanced or retracted by one minute.

Therefore, the operator operates the keys 43a and 43b to display, for example, 19:00 (PM7: 00). Then, of the ram speed setting keys 47a to 47e, for example,
When 47e is pressed, LED indicator 45e lights up, then key 4
Pressing 3d will now set the ram speed well after 19:00 with the ram speed being controlled at the minimum speed. After the ram speed setting work is completed, if the key 43c is pressed again, the LCD display 41 will display the current time again.

For speed setting keys 47a to 47e, key 47a sets the maximum speed, and key 4
7e is for setting the minimum speed.

By the operation as described above, the operator can specify the daily schedule regarding the ram speed. As an example, as shown in Fig. 3, it is high speed from 8:00 am to 7:00 pm, medium speed from 7:00 to 9:00 pm, and night.
It seems that the speed is low from 9:00 to 6:00 the next day, and then medium speed until 8:00 in the morning. The schedule set once does not change until the next change.

FIG. 2 shows a block diagram of the control device.

The control device 37 includes a ram speed setting processing unit 49 and a display control unit 51.
A press control unit 55 having a clock 53, a motor control unit 57, a clutch brake control unit 59, and a clutch control unit 61.

The ram speed setting processing unit is a control unit that processes designation of each key provided on the operation panel 39. The display control unit 51 is
A driver for the LCD display 41.

The clock 53 is, for example, a quartz clock, and supplies a predetermined clock to the press control unit 55.

The press control unit 55 stores the schedule shown in FIG. 3 and outputs a predetermined control signal to each unit in a timely manner so that each unit performs a predetermined control.

The motor control unit 57 receives a command from the press control 57 and controls the motor drive power supply 35.

The motor drive power supply 35 includes a commercial frequency power supply 63 and a switch 65.
And an inverter 67 and a thermal switch 69. The motor control unit 57 controls the opening / closing of the switch 65 according to the start and end of the work and outputs the frequency change command according to the schedule shown in FIG. 3 to the inverter 67. Therefore, the three-phase motor M comes to rotate at a predetermined speed according to the schedule shown in FIG.

The clutch brake control unit 59 inputs the detection signal of the limit switch 17 and controls the clutch brake 19. The clutch brake 19 is normally in a state where the clutch is off and the brake is on when the ram 13 is at the top dead center position. Then, based on the ram operation command, the clutch is turned on,
When the brake is turned off and the ram 13 comes back to the position before top dead center again, the clutch is turned off and the brake is turned on.
It acts to stop 13 at the top dead center position. here,
The position before the top dead center of the ram 13 is detected by the limit switch 17.

By the way, in this example, the motor M is driven at a different speed with respect to time based on the schedule as shown in FIG. Therefore, in this example, in order to stop the ram 13 accurately at the top dead center position, the clutch brake control unit 59
Is the clutch brake control signal CB, as shown in FIG.
Output C. The clutch brake control signal CBC is a signal for controlling the clutch brake 19 by delaying from the detection time Tmo of the limit switch 17 by an amount δTm proportional to the deceleration amount of the motor M. As a result, the ram 13 always stops accurately at the top dead center position regardless of the rotation speed of the motor M.

The clutch control unit 61 is for controlling contact / separation (on / off) of the clutch 31. Clutch control signal FWC
As shown in FIG. 4, when the rotational speed of the motor M is slowed down, when normal press working is performed with the energy of the main flywheel 21 at the rotational speed at that time, the rotational speed of the main flywheel is This signal is a signal for turning on the clutch 31 and joining the sub flywheel 33 to the main flywheel 21 when the reduction continues and the recovery is not achieved. As a result, when the motor M rotates at a low speed, the flywheel can rotate the shaft 9 in cooperation with the main and sub axes, so that the reduction in the energy of the main flywheel 21 is reduced by the energy of the sub flywheel 33. As a result, the smooth operation of the ram 13 can be guaranteed.

FIG. 6 is an explanatory diagram showing the theory of noise reduction.

The control device 37 shown in FIGS. 1 to 5 is controlled according to the schedule shown in FIG.

Therefore, the speed V of the ram 13 is now 30% of the normal speed V _100.
Suppose that it is set to V ₇₀ that is a low amount.

The punch 11 provided at the lower end of the ram 13 normally shears the plate material W having a predetermined thickness in a time ΔT _F , and this time ΔT _F is
Due to the decrease in the speed of the ram 13, the time becomes ΔT _S longer than this. Here, at times ΔT _F and ΔT _S , the lower end of the punch 11 touches the plate material W and bites into the plate material W (T ₁ ), and then a so-called crack occurs in the plate material (T ₂ ), and the plate material W Shows the time ΔT = T ₂ −T ₁ until it is sheared at once.

Although details of the cause of noise are omitted, it has been experimentally confirmed that the noise depends on the time ΔT, and the noise decreases as the time ΔT increases. Therefore, as described above, when the ram speed V is reduced by 30%, the noise is reduced by 20 to 30%.

As described above, the control device 37 applied to the press machine 1 shown in this embodiment operates the ram 13 of the press machine 1 according to the schedule shown in FIG. 3 to minimize noise generated at night, for example. Will be able to.

In this example, the ram speed is controlled to be slowed by about 20% on average at night (PM7: 00 to AM8: 00), but in general,
The ram work time in the entire press work is about 50 to 75%, and the work speed decrease due to the ram speed decrease is 12.5-1.
It is only about 8.8%.

Thus, by using the control device 37 shown in this example, the press machine 1 can perform the press work with low noise and high efficiency.

Further, the control device 37 shown in this example is suitable for retrofitting an existing press machine. That is, the control device 37 shown in FIG. 2 can be easily incorporated into a press machine as a control device for an existing press machine, and the inverter 37
The 35, the clutch 31, and the auxiliary flywheel 33 are also configured to be easily retrofitted to the existing press machine.

In the embodiment shown above, the ram speed is set with respect to the time on the operation plate 39, but it goes without saying that the ram speed can be set with respect to time.
For example, when a plate material having a large plate thickness is continuously processed for a predetermined time, it is possible to schedule the speed of the ram 13 to be reduced for the predetermined time.

In the embodiment described above, the speed of the ram 13 is changed by controlling the rotation speed of the three-phase motor using the inverter 67. However, a servo motor is used as the motor and the motor is a servo amplifier. Ram by driving
13 speeds may be changed.

Further, in the above-described embodiments, one example of a crank press that performs punching as a press machine is shown, but the control device according to the present invention is a press machine that performs drawing, a turret punch press, a cylinder type press machine. It is also applicable to. In a cylinder type press machine, as a ram speed control means, for example, a throttle valve in a supply / discharge circuit to / from a cylinder may be controlled.

It is also possible to connect a noise level meter to the control device according to the present invention and perform feedback control regarding noise and ram speed.

[Effect of the Invention] According to the control device for a press machine of the present invention, the press machine can be operated with low noise and high efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of a press machine showing an example to which the present invention is applied. FIG. 2 is a block diagram of a control device for a press machine according to an embodiment of the present invention. FIG. 3 is an explanatory diagram showing a ram speed schedule. FIG. 4 is an explanatory diagram of clutch control signals corresponding to the schedule shown in FIG. FIG. 5 is an explanatory diagram of clutch brake control signals corresponding to the schedule shown in FIG. FIG. 6 is an explanatory diagram of the cause of noise generation. 1 …… Crank press 13 …… Ram 19 …… Clutch brake 31 …… Clutch 33 …… Sub flywheel 39 …… Operating panel 41 …… Time display 43 (43a to 43d) …… Time setting key 47 (47a ～ 47e) …… Ram speed setting key 67 …… Inverter M …… 3-phase motor

Claims (2)

[Claims] 1. A main flywheel 21 and an auxiliary flywheel 33.
Are provided in the press machine, and the control device of the press machine sets the ram speed of the press machine to a ram speed setting processing section 49.
A motor drive power supply device 35 having an inverter, a motor control unit 57 for controlling the motor drive power supply device, a clutch brake 19 of the main flywheel 21, a main flywheel 21 and a sub flywheel 33. Free clutch
31. A press machine control device comprising a press control unit 55 for controlling the control unit 31 and a ram setting speed operation panel 39 including a clock operation key, a speed setting key, and a time display. 2. The ram speed setting processing section 49 controls the press machine to the set ram speed for a set time or time. The control device for a press machine according to claim 1.