JPH05318199A - Fixed position stopping method of press machine - Google Patents

Abstract

PURPOSE:To efficiently and precisely stop a crank shaft and further a slide by applying a braking operation again after reducing the velocity down within a velocity area low in some extent with a 1st time breaking operation. CONSTITUTION:At the time of executing the stopping operation of the press machine, a 1st set angle to apply a braking force to the crank shaft 2 based on a position where the crank shaft 2 is stopped is set. When the rotation angle of the crank shaft reaches the 1st set angle, a clutch 5 which transmits the rotation force to the crank shaft 2 of the press machine is released, an when the crank shaft 2 reaches the stationary rotation velocity of low velocity, a 2nd set angle of the crank shaft 2 to apply a braking force to the crank shaft 2 again based on the position where the crank shaft 2 is stopped is set. When the rotation angle of the crank shaft 2 reaches the 2nd set angle, the crank shaft is stopped by operating the brake again.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for stopping a crankshaft, and hence a slide, of a press machine at a fixed position,
It can be effectively used for press machines, especially high-speed press machines.

[0002]

2. Description of the Related Art In recent years, in order to improve workability, high speed, for example, 300 SPM (number of strokes per minute of slide,
Press machines with strokes / minute) have been used. Brake braking in such a press machine is usually performed by one brake operation.

[0003]

However, in one-time braking, particularly in a high-speed machine of 150 SPM or more, unstable idling amount due to response delay of braking operation, unstable braking ability, and other causes. The braking angle amount changes significantly due to the error. As a result, the stop position accuracy of the crank angle of the press machine varies greatly, the stop position accuracy of the slide, feed device, and other devices changes, which not only makes the operation of the press machine unstable, but also There is a problem that the safety is impaired.

As an example for solving such a problem, there is an invention disclosed in Japanese Patent Laid-Open No. 57-206598.

According to the invention disclosed in this publication, when the first detector approaches the peak of the rotary cam fixed to the crankshaft, the brake is applied and the clutch is disengaged. In this state, the crankshaft decelerates, and when the rotation speed set by the tachogenerator provided on the crankshaft is detected, the brake is released and the crankshaft is decelerated to a constant rotation speed. Then, when the mountain portion of the rotary cam approaches the second detector, the brake is applied again, so that the crankshaft and thus the slide stop at the fixed position.

However, according to the present invention, since the timing for applying the brake is set by the rotary cam and the two detectors which are fixedly provided, 150
In the high speed range of SPM or higher, the efficiency was high and proper braking could not always be achieved.

That is, during high-speed operation, it is difficult to set a low-speed constant rotation by the first brake braking, and when the low-speed rotation speed changes, a second signal is output from the second detector. This is because even if the brake is operated, the final stop position of the crankshaft changes, and precise control cannot be performed.

On the other hand, in order to stabilize the stop position by the second braking operation, if the braking operation is repeated so that the rotation speed detected by the tachogenerator becomes constant, the braking operation takes time and efficient braking is performed. The other problem of inability to operate occurs.

The object of the present invention is 150S as well as low speed range.
It is an object of the present invention to provide a fixed-position stopping method for a press machine that can efficiently and accurately stop the crankshaft position even in a high-speed region above PM.

[0010]

The present invention is based on the first and second aspects.
The above object is to be achieved by calculating, setting, or predicting the second braking position by a computer or the like.

Specifically, according to the present invention, when the pressing operation of the press machine is performed, the angle of the crankshaft (first set angle) at which the braking force should be applied to the crankshaft based on the position where the crankshaft should be stopped. When the rotation angle of the crankshaft reaches the first set angle, the clutch transmitting the rotational force to the crankshaft of the press machine is released, and the brake is operated to change the rotation speed of the crankshaft. When the crankshaft is decelerated, and then the rotation speed of the crankshaft reaches a predetermined speed, the brake operation is released to wait for the crankshaft to rotate at a low speed and a low speed, and then the rotation speed becomes a low speed at a constant speed. At that time, the angle of the crankshaft (second set angle) at which the braking force should be applied to the crankshaft is set again based on the position where the crankshaft should be stopped again, and the rotation angle of the crankshaft is set to the second setting value. When it is angular, it is a press machine of fixed-position stop method characterized by stopping the crankshaft applies the brakes again.

[0012]

In the present invention, since the brake operation is performed again after decelerating to a low speed range to some extent by the first brake operation, the brake stop accuracy becomes good, and the idling amount in the high speed range fluctuates greatly. Even so, because the stop position is predicted again in the low speed range, the effect does not affect the stop accuracy,
Stop accuracy becomes precise.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a press machine for carrying out the home position stopping method according to the present invention and a control device therefor.
In the figure, a crankshaft 2 is rotatably supported on an upper portion of a press body 1, and an eccentric portion 2A of the crankshaft 2 is connected with a slide 4 via a connecting rod 3. It is slidably supported in all directions.

A flywheel 6 is attached to one end of the crankshaft 2 via a clutch 5, and the flywheel 6 is constantly rotated by a motor 7 via a belt 8. Further, the motor 7 is provided with a tacho-generator 9, and the tacho-generator 9 detects the rotation speed of the motor 7. A brake 11 is provided at the other end of the crankshaft 2, and the rotational state of the brake 11, that is, the rotation speed information and the rotation angle information is detected by the rotary encoder 12. The output signal ES of the encoder 12 and the output signal TG of the tachogenerator 9 are respectively input to the CPU 14 as an arithmetic unit such as a computer via the I / O 13 as an interface. Operation data such as a press stop operation is input to the CPU 14 from a keyboard 15 or the like which is an input device.

Solenoid valves 16 and 17 for pneumatically operating the clutch 5 and the brake 11, respectively, are connected, and these solenoid valves 16 and 17 are connected to the solenoid valves 16 and 17, respectively.
Air is supplied from an air tank 19 connected to the pressurized air source 18. An electric signal for switching is applied to the solenoid valves 16 and 17 from the CPU 14 through the I / O 21, and the clutch 6 and the brake 11 are driven by the electric signals via the solenoid valves 16 and 17. It is controlled.

Next, the stopping method of this embodiment will be described with reference to the speed diagram of FIG. 2 and the flowchart of FIG. In FIG. 2, the vertical axis represents the crankshaft speed (angular speed) V.
The horizontal axis indicates the crankshaft angle P.

During operation of the press device, a predetermined signal is output from the CPU 14 to the solenoid valves 16 and 17 based on an instruction from the keyboard 15, the clutch 5 is put in the connected state, and the brake 11 applies the braking force. It is in a released state. At this time, the crankshaft 2 is rotated at a predetermined speed (angular speed) V ₁ (see FIG. 2) via the belt 8, the flywheel 6 and the clutch 5 by the rotational force of the motor 7. In such a state, the CPU 14 checks whether or not the press machine stop signal is issued from the keyboard 15. This state is indicated by step 31 in FIG.

When the stop operation of the press machine is detected in step 31, the current speed information, that is, the rotational speed information (T) of the tachogenerator 9 is detected in step 32.
G) and the rotation speed and rotation angle (position) information (ES) of the rotary encoder 12 are captured. Next, based on these information, in step 33, in order to stop the crankshaft 2 and thus the slide 4 at a predetermined position, for example, the top dead center position, the clutch 5 and the clutch 5 are operated at any time and at what position (crankshaft angle). The CPU 14 calculates (predicts) whether or not to output to the brake 11, and the set value P ₁ of the output position (angle) is set. This set value P ₁ is the first set angle.

Set value P₁The more specific setting method of
It is as follows. Rotation angle from rotary encoder 12
The degree position information ES is set at a predetermined time interval, for example, an interval of 2 msec.
Is read into the CPU 14. This read two consecutive
The advance angle for 2msec is obtained by taking the difference of the data of
Angular velocity V of the crankshaft 2 depending on the degree ₁To get On the other hand, an octopus
Read the rotation speed information TG directly from the generator 9.
Check the operation of the TG and ES by checking if there is a difference between the values.
The reality is raised.

That is, since the rotary encoder 12 has a large resolution, it has a small SPM, for example, 50 SP.
Below M, the data read from the rotary encoder 12 may fluctuate significantly. In this case, the information TG from the tacho generator 9 is used as a reference in order to increase the certainty of the data. However, since the tacho generator 9 is provided on the motor 7 side, after the clutch 5 is turned off,
It is not helpful as data. Therefore, the data (information ES) from the rotary encoder 12 is used as basic data. Moreover, in the low-speed range, the number of readings is increased and the average value is given to stabilize the data.

As a result of comparing the information ES and TG, if there is no deviation in the numerical value, the data (information ES) from the rotary encoder 12 is set to V ₁ . When the deviation is large, the information ES is read again from the rotary encoder 12 and the calculation is performed based on the new ES to set the set value P ₁ .

The setting value P ₁ is set by comparing the angular velocity V ₁ which is data with a unique data table of the clutch 5 and the brake 11. The data table is unique data of the clutch 5 and the brake 11 that, at a certain speed, for example, a speed V ₁ , if the brake 11 is operated so as to operate at a certain point P ₁ , braking is started at a certain point P ₂ . Is a table,
It is stored in advance in a memory (not shown) associated with the CPU 14. This data table is, for example, 10 SPM-
It is created over the entire area up to MaxSPM.

At step 34, the rotary encoder is
The angle (position) of the crankshaft 2 based on the information from the da 12
Is the set value P where is the first set angle₁Check if
And set value P₁Then, via the input / output device 21,
A signal is output to the renoid valves 16 and 17. By this
The clutch 5 is engaged as shown in step 35.
The brake force is applied to the crankshaft 2 by the brake 11.
To work, ie clutch off, brake
ON operation is performed. By this operation, the crankshaft 2
The braking force acts on the crankshaft 2 and the rotation of the crankshaft 2 is reduced.
However, in reality, it is due to the response delay after output.
As shown in FIG. 2, the braking start point P ₂To run free
Occur. This fluctuation in free running amount is the main cause of deterioration in stopping accuracy.
Has become.

After the start of braking, the crankshaft speed linearly decreases as shown in FIG. 2, and it is checked in step 36 whether this speed reaches a predetermined value V _X. When the speed V _X is detected, in step 37, a signal for releasing the braking force of the brake 11 is output (brake OFF point P ₃ ). Also at this time, as shown in FIG. 2, the brake braking force acts for a while due to the response delay, and the crankshaft 2 reaches the constant speed V ₂ point P ₄ at the low speed and becomes stable only at the constant low speed. Constant speed V ₂ , eg 2
It becomes 0 SPM. Step 3 is to stabilize at constant speed V _2.
If it is checked in step 8, in step 39, in order to stop the crankshaft 2 accurately at a predetermined position, the CPU 14 determines again at which rotation angle position of the crankshaft 2 or the brake 11 the brake output should be issued again. It is calculated (predicted) and its value P ₅ is set. This set value P ₅ is the second set angle. The setting of the set value P ₅ is performed in the same manner as the case of the set value P ₁ described above.

When it is detected in step 40 that the angle of the crankshaft 2 has reached the installation value P ₅ which is the second set angle, at this point P ₅ (brake re-ON point),
As shown in step 41, the brake output is turned on again. Also in this case, the braking force of the brake 11 does not actually act until the braking start point P ₆ due to the response delay, and after this braking start, the rotation speed of the crankshaft 2 is gradually reduced to the stop point. It will be stopped at P ₇ . This stop is checked in step 42. At this time, since the constant speed V ₂ at low speed has a relatively small value, the stop position of the crankshaft 2 is accurately stopped, for example, about ± 3 degrees. The stop position is usually a position where the crank 2 is at the top dead center.

By the way, the braking force of the brake 11 varies.
As shown by the broken line in Fig. 2, the braking start point
P₂From the solid line, braking is performed at a gentler angle than the solid line_xWhen
Brake OFF point Q₃The brake was turned off at
If so, in this case, since the braking force is weak, the crankshaft 2
Is the constant speed V₂Larger constant velocity V₃Is low speed timed
Speed V₃Point Q_FourWill stabilize the speed. Therefore,
Constant speed V ₂At the same timing as in
When a braking force is applied, the stop point P₇Can be stopped by
It will be difficult. In this case, step 39 described above is used.
The brake re-output position is calculated again and the set value is
Q_FiveIs set, the set value P_FiveBraking earlier
Starting point Q₆Braking starts from the end, and finally the same stop as above.
Stop point P₇Will be stopped at.

Further, the braking force of the brake 11 is stronger,
When braking is performed at a speed faster than the deceleration state indicated by the solid line, constant rotation is performed at a value smaller than the constant speed V _2, but in this case as well, recalculation is performed and a new stop start set value is set. Is set, the final stop point is P ₇ .

Further, even if the initial crankshaft speed V ₁ is higher or lower than this value, the two-step braking operation is similarly calculated and performed, and the final stop point is always constant, that is, 2, the stop point P ₇ is set.

According to this embodiment as described above, the following effects can be obtained. In other words, the braking operation by the brake 11 is not carried out from being in a single operation from the high speed range, after once reduced to a certain rotation of the low speed, to be braking operation again, empty due to the constant speed V ₂ at a low speed The running range is reduced, the deviation of the stop position is greatly reduced, and the accuracy is greatly improved. Moreover, even at this low speed constant speed V ₂ , the stop position is predicted again, so even if there are variations in the constant speed V ₂ , the influence does not affect the stop accuracy, and more accurate stop can be performed. ..

Further, by performing recalculation (prediction) at a low speed, the constant speed V ₂ at a low speed can be accurately stopped without necessarily having to be a predetermined speed. It is not necessary to control the speed to a predetermined speed by repeating the above, and the workability can be improved.

Further, the control device by the CPU 14 can be easily manufactured by using a microcomputer or the like, has high versatility, and can be provided at a low cost unlike a rotary cam or the like which is required for each different rotation speed.

When setting the clutch OFF and the brake ON point P _{1 for} the _first brake braking, not only the output signal ES of the rotary encoder 12 but also the output signal TG of the tachogenerator 9 is set. Therefore, the rotation information of the motor 7 whose speed is stable can be used to correct the rotation information of the brake 11 whose speed changes frequently, and a more stable set value P ₁ can be set. In particular, in the past, when the rotational speed of the press fluctuated significantly due to an emergency stop or the like, it was impossible to stop at a fixed position, but according to the present embodiment, it is possible to sufficiently secure control followability and stabilize It is possible to stop the fixed position.

The present invention is not limited to the above-mentioned embodiments, but is improved within a range in which the object of the present invention can be achieved,
Modifications and the like are included in the present invention.

For example, in the above embodiment, when the set value P ₁ for applying the _first braking force is applied,
Although not only the output signal ES of the rotary encoder 12 but also the output signal TG of the tacho generator 9 is referred to,
It is not always necessary to perform both, and it may be performed only with the output signal ES of the encoder 12. However, the effects described above can be expected by referring to both. Further, the driving force of the clutch 5 and the brake 11 is not limited to the compressed air as in the above embodiment, but may be an electromagnetic force, and its method is not limited. Further, the CPU 14 as an arithmetic unit can use a personal computer and other general control means.

[0036]

As described above, according to the present invention, there is an effect that the crankshaft of the press machine, and hence the slide, can be accurately stopped.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a schematic configuration of an embodiment of a press device to which a stopping method according to the present invention is applied.

FIG. 2 is a velocity diagram showing an example of an operating state of the present invention.

FIG. 3 is a flowchart in one embodiment of the present invention.

[Explanation of symbols]

 1 Press Main Body 2 Crankshaft 4 Slide 5 Clutch 6 Flywheel 11 Brake 12 Rotary Encoder 14 CPU as Computing Device 15 Keyboard

Claims (2)

[Claims] 1. When the operation of stopping the press machine is performed,
An angle (first set angle) of the crank shaft to which a braking force should be applied to the crank shaft is set based on the position where the crank shaft should be stopped, and when the rotation angle of the crank shaft reaches the first set angle, the press machine The clutch transmitting torque to the crankshaft is released, and the brake is actuated to decelerate the rotation speed of the crankshaft. Then, when the rotation speed of the crankshaft reaches a predetermined speed, the brake is released. Wait until the crankshaft reaches low-speed constant speed rotation by releasing the operation of, and apply braking force to the crankshaft based on the position where the crankshaft should be stopped again when this low-speed constant speed rotation is reached. Setting the angle of the crankshaft (second set angle), and when the rotation angle of the crankshaft reaches the second set angle, reactivate the brake to stop the crankshaft. Fixed-position stop method of a press machine, characterized. 2. The fixed position stopping method according to claim 1, wherein the setting of the first set angle is performed by referring to rotational speed information of a motor for rotating the crankshaft and rotational speed and rotation angle information of the crankshaft. A method for stopping a fixed position of a press machine, which is characterized in that: