JP2711980B2 - Diagnosis method of pressure equalizing condition of pressure equalizing cushion device and pressure equalizing condition setting device using the method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure equalizing cushion device for a press machine, and more particularly to a method for diagnosing a pressure equalizing condition for distributing a wrinkle holding load substantially uniformly and a setting of the pressure equalizing condition using the method. It concerns the device.

[0002]

[Prior art]

(A) a cushion pad to which a wrinkle pressing load is applied by a wrinkle pressing load applying means; (b) a plurality of hydraulic cylinders disposed on the cushion pad and having hydraulic chambers communicated with each other; A plurality of cushion pins respectively disposed on the hydraulic cylinder and supporting the wrinkle presser die at the upper end, wherein the press upper die is lowered so that the press upper die and the wrinkle presser die When press working is performed between the press upper die and the press lower die while pressing the work in, the wrinkle pressing load applied to the wrinkle pressing die by the wrinkle pressing load applying means by the hydraulic cylinder. 2. Description of the Related Art There is known a pressure equalizing cushion device of a press machine in which the pressure is equally distributed to a plurality of cushion pins. 1
The apparatus described in Japanese Patent No. 60721 is an example of such a press machine. In such a press machine, the wrinkle pressing load is substantially uniform regardless of the variation in the length of the cushion pin and the inclination of the cushion pad. As a result, the surface pressure distribution of the wrinkle retainer becomes substantially constant, so that good press working can always be performed.

Here, in order to distribute the wrinkle holding load evenly as described above, all the hydraulic cylinder pistons are driven into the cylinder at the time of press working irrespective of the variation of the length of the cushion pin and the like. At the same time, it is necessary to keep the piston in a neutral state so as not to reach the end of the stroke. For this reason, the average driving dimension Xav of the piston of the hydraulic cylinder,
Based on the pressure receiving area As of the hydraulic cylinder, the bulk modulus K of the working oil used, the oil amount V, the wrinkle holding load Fs, and the number n of the cushion pins used, the equalizing initial oil pressure Po of the hydraulic cylinder, that is, the uniform wrinkle holding load. Is determined so as to satisfy the following expression (1). The average run-in dimension Xav is the run-in stroke of the piston for bringing all the cushion pins into contact with the wrinkle presser die, regardless of the variation in the length of the cushion pins, the inclination of the cushion pad, etc. The piston is pushed into the cylinder by the cushion pin, and is determined in advance by an experiment or the like so that the piston does not reach the stroke end irrespective of an impact at the time of press working. Further, in a state where the pistons of all the hydraulic cylinders are located at the protruding ends, the oil amount V is the total amount of the hydraulic oil in the hydraulic chamber of the hydraulic cylinder or a series of hydraulic circuits communicating with the hydraulic chamber. Capacity.

[0004]

Xav = (Fs−n · As · Po) V / n ² · As ² · K (1)

[0005] The initial hydraulic pressure P is set so as to satisfy the above equation (1).
When o is set, the piston of each hydraulic cylinder is basically driven into the cylinder by the average drive-in dimension Xav during press working, and the wrinkle holding load is applied to the wrinkle holding mold almost uniformly via each cushion pin. Can be
The initial oil pressure Po is not always accurate, for example, the bulk modulus K changes due to air mixing or deterioration of hydraulic oil. For this reason, the wrinkle holding load Fs and the weight W
r, the average weight Wp of the cushion pins, the number n of the cushion pins used, and the pressure receiving area As of the hydraulic cylinder,
According to the following equation (2), an equalizing pressure generating oil pressure PXo, which is a hydraulic pressure at the time of press working at the time of equalizing, is obtained, and a test press is performed so that the generated oil pressure PX at the time of the press working substantially matches the equalizing pressure generating oil pressure PXo. The initial pressure Po is corrected.

[0006]

Fs + Wr + n · Wp = n · As · PXo (2)

[0007]

As described above, the average run-in dimension Xav and the pressure receiving area As, which are necessary for calculating the equalizing initial oil pressure Po and the equalizing pressure oil pressure PXo, are described above.
Since the bulk modulus K, the oil amount V, etc., must be as accurate as possible, it is necessary to obtain not only design values but also actual press machines in advance for each press machine using experiments, etc.
Extremely troublesome work was required. In addition, since the value thus obtained also has a predetermined error, an error occurs in the initial pressure for equalizing pressure Po and the pressure for generating equalizing pressure PXo. A state could not be obtained, and press failure could occur due to uneven surface pressure distribution of the wrinkle retainer. Further, it is also performed to compare the above-mentioned equalized pressure generation oil pressure PXo with the generated oil pressure at the time of actual press working to monitor whether or not the press working is performed in the equalized state. It cannot be determined exactly whether or not there is.

The present invention has been made in view of the above circumstances, and an object of the present invention is to simply set an equalizing condition relating to an initial hydraulic pressure and a generated hydraulic pressure capable of uniformly distributing a wrinkle pressing load to a plurality of cushion pins. In addition, it is necessary to be able to be accurately obtained.

[0009]

According to a first aspect of the present invention, there is provided a fuel cell system comprising: (a) a cushion pad; (b) a plurality of hydraulic cylinders; and (c) a plurality of cushion pins. When the press upper die is lowered, the press work is performed between the press upper die and the press lower die while pressing the work between the press upper die and the wrinkle presser die, In a pressure equalizing cushion device of a press machine for distributing a wrinkle holding load applied to the wrinkle holding mold by the wrinkle holding load applying means to the plurality of cushion pins by the hydraulic cylinder, the wrinkle holding load is substantially evenly distributed. A method of diagnosing a pressure equalization condition relating to a hydraulic pressure of the hydraulic cylinder for distributing,
(D) a hydraulic pressure detecting step of checking the relationship between the initial hydraulic pressure and the generated hydraulic pressure by detecting the generated hydraulic pressure of the hydraulic cylinder during the pressing while changing the initial hydraulic pressure of the hydraulic cylinder during the non-press processing; (E) a step of determining, based on the relationship between the initial hydraulic pressure and the generated hydraulic pressure, an equalized initial hydraulic pressure region in which the generated hydraulic pressure becomes substantially constant regardless of a change in the initial hydraulic pressure.

[0010]

In other words, when the generated oil pressure is examined while changing the initial oil pressure while keeping other press working conditions such as the wrinkle holding load constant, the initial oil pressure and the generated oil pressure have a relationship as shown in FIG. In the region A where the initial hydraulic pressure is the highest, all the pistons of the hydraulic cylinders do not operate at all, but in the region B where the initial hydraulic pressure is lower than that, some pistons of the hydraulic cylinders You will be pushed inside. However, some other hydraulic cylinders, for example, the pistons of the supporting hydraulic cylinder having a short cushion pin do not operate, and the pressure is not completely equalized. When the pushing stroke of the working hydraulic cylinder is lengthened due to a decrease in the initial hydraulic pressure, the number of operating hydraulic cylinders increases accordingly, and the wrinkle holding load is distributed to those hydraulic cylinders. As the pressure decreases, the generated hydraulic pressure decreases.

In the area C, the pistons of all the hydraulic cylinders are driven into the cylinders and are held in a neutral state without reaching the stroke end. The wrinkle holding load reduces the hydraulic pressure of those hydraulic cylinders. Is evenly distributed to each cushion pin. This C region is an equalizing initial hydraulic pressure region, and in this range, the generated hydraulic pressure is substantially constant because the piston position only slightly moves to the stroke end side as the initial hydraulic pressure decreases. Further, in the region D, the pistons of some of the hydraulic cylinders are in a torsion state reaching the stroke end, and the pressure equalization state is broken. In the rear end state, the wrinkle holding load is transmitted without the intermediary of the hydraulic pressure, so that the generated hydraulic pressure decreases as the initial hydraulic pressure decreases.

The term "all hydraulic cylinders" does not mean all the hydraulic cylinders provided on the cushion pad. Rather, the cushion pins are arranged on the cushion pads. A hydraulic cylinder whose piston is driven into the cylinder
That is, it is a hydraulic cylinder that actually participates in the wrinkle presser.

[0013] In addition, the variation in the length of the cushion pin is large, or the piston stroke of the hydraulic cylinder is small, so that some of the hydraulic cylinders are inactive and some of the other hydraulic cylinders are in a torsion state. In such a case, if the equalizing initial hydraulic pressure area C cannot be clearly distinguished, for example, the equalizing initial hydraulic pressure area C does not appear, or if a plurality of equalizing initial hydraulic pressure areas appears, some Means that there is an abnormality.

Therefore, the relationship between the initial oil pressure and the generated oil pressure is examined by detecting the generated oil pressure while changing the initial oil pressure, and the equalized initial oil pressure region (FIG. 1) where the generated oil pressure is substantially constant irrespective of the change in the initial oil pressure. C region), the pressure equalizing condition relating to the hydraulic pressure for distributing the wrinkle holding load substantially uniformly based on the equalizing initial hydraulic pressure region, that is, the equalizing initial hydraulic pressure Po and / or the equalizing pressure generating hydraulic pressure. PXo can be known. Specifically, the initial oil pressure in the equalizing initial oil pressure region is equalizing initial oil pressure Po that can evenly distribute the wrinkle pressing load to each cushion pin during press working, and equalizes the initial oil pressure before press working. If the pressure is adjusted to the initial hydraulic pressure Po, the surface pressure distribution of the wrinkle retainer during press working can be made substantially constant. The generated oil pressure in the equalizing initial oil pressure region is equalizing pressure generating oil pressure PXo. For example, the initial oil pressure is corrected so that the generated oil pressure substantially matches the equalizing pressure generating oil pressure PXo, or the generated oil pressure during actual press working is used. By monitoring whether the pressure is substantially equal to the equalizing pressure generating pressure PXo, it is possible to judge a press failure caused by foreign matter biting in the hydraulic cylinder or the like. The wrinkle holding load can also be obtained. on the other hand,
If the equalizing initial hydraulic pressure region cannot be clearly determined, it can be diagnosed that some abnormality exists in the equalizing cushion device.

[0015]

As described above, according to the equalizing pressure condition diagnosing method of the present invention, the above equation (1) or (1) can be obtained by using the average driving dimension Xav, the pressure receiving area As, the bulk modulus K, the oil amount V, and the like. 2)
It is possible to easily and accurately determine the pressure equalizing condition regarding the hydraulic pressure of the hydraulic cylinder and diagnose an abnormality of the pressure equalizing cushion device without calculating according to the formula.

[0016]

According to a second aspect of the present invention, there is provided a fuel cell system comprising: (a) a cushion pad; (b) a plurality of hydraulic cylinders; and (c) a plurality of cushion pins. When the press upper die is lowered, the press work is performed between the press upper die and the press lower die while pressing the work between the press upper die and the wrinkle presser die, In a pressure equalizing cushion device for a press machine for distributing a wrinkle holding load applied to the wrinkle holding mold by the wrinkle holding load applying means to the plurality of cushion pins by the hydraulic cylinder, the wrinkle holding load is substantially evenly distributed. A method of diagnosing a pressure equalization condition relating to a hydraulic pressure of the hydraulic cylinder for distributing,
(D) a wrinkle pressing step of lowering the press upper die to a predetermined wrinkle pressing state in which the press upper die presses the wrinkle pressing die; and (e) a hydraulic circuit communicating with the hydraulic cylinder in the wrinkle pressing state. A hydraulic pressure detecting step of detecting the hydraulic pressure of the hydraulic oil while changing the oil amount of the hydraulic oil in the
(F) determining a region in which the hydraulic pressure is substantially constant irrespective of a change in the amount of the hydraulic oil as a pressure equalizing region.

[0017]

In other words, the change in the amount of hydraulic oil in the hydraulic circuit communicating with the hydraulic cylinder is substantially the same as the change in the initial hydraulic pressure in the first aspect of the present invention, so that the wrinkle holding load can be distributed substantially evenly. In the pressure equalizing region, the hydraulic pressure does not change, only the piston position changes with the change in the amount of hydraulic oil. Therefore, in a state where the press upper die is lowered to a predetermined wrinkle holding state such as a bottom dead center, the oil pressure of the hydraulic oil is detected while changing the oil amount of the hydraulic oil in the hydraulic circuit communicating with the hydraulic cylinder, and the operation is performed. The region where the oil pressure is substantially constant irrespective of the change in the oil amount may be determined as the equalizing region. The hydraulic pressure in the pressure equalizing region is the pressure equalizing pressure PXo. Like the first invention, for example, the hydraulic pressure is equal to the pressure equalizing pressure PXo.
By compensating the initial oil pressure so that it substantially matches the pressure, or monitoring whether or not the oil pressure generated during actual press working is substantially equal to the equalized pressure oil pressure PXo, it is possible to prevent foreign matter from being caught in the hydraulic cylinder, etc. It is possible to judge the resulting press failure, and it is also possible to obtain the wrinkle holding load from the pressure equalizing pressure PXo. If the pressure equalizing region cannot be clearly determined, it can be diagnosed that some abnormality exists in the pressure equalizing cushion device.

[0018]

[Effect of the Second Invention] As described above, also in the second invention,
Simple and accurate equalization conditions relating to the hydraulic pressure of the hydraulic cylinder without calculating according to the formulas (1) and (2) using the average run-in dimension Xav, the pressure receiving area As, the bulk modulus K, the oil amount V, and the like. That is, it is possible to obtain the equalizing pressure generation oil pressure, and to perform abnormality diagnosis of the equalizing cushion device. Moreover, in the second invention, it is sufficient to detect the hydraulic pressure while changing the amount of hydraulic oil in a predetermined wrinkle holding state, so that the press is operated every time the initial hydraulic pressure is changed as in the first invention. Compared with the case of detecting the oil pressure, the pressure equalization condition can be diagnosed easily and quickly, and the automatic pressure equalization diagnosis can be easily automated.

[0019]

In order to achieve the above-mentioned object, a third aspect of the present invention is directed to the present invention, as shown in the claim correspondence diagram of FIG. A cylinder and (c) a plurality of cushion pins,
When the press upper die is lowered, when press processing is performed between the press upper die and the press lower die while pressing the work between the press upper die and the wrinkle pressing die,
In a pressure equalizing cushion device for a press machine for distributing a wrinkle holding load applied to the wrinkle holding mold by the wrinkle holding load applying means to the plurality of cushion pins by the hydraulic cylinder, the wrinkle holding load is substantially equalized. (D) hydraulic pressure detecting means for detecting the hydraulic pressure of the hydraulic cylinder, and (e) hydraulic pressure detecting means for detecting the hydraulic pressure of the hydraulic cylinder during non-press working. And (f) changing the initial oil pressure by the initial oil pressure changing means based on the generated oil pressure of the hydraulic cylinder detected by the oil pressure detecting means during press working. A change amount calculating means for calculating a change amount of the accompanying generated oil pressure; and (g) a change amount of the generated oil pressure calculated by the change amount calculating means. Determining means for determining whether or not the change amount is equal to or less than a predetermined value; and (h) based on an equalizing initial oil pressure area in which the amount of change in the generated oil pressure is determined to be equal to or less than the predetermined value. Setting means for obtaining and setting pressure equalization conditions relating to the hydraulic pressure of the hydraulic cylinder.

[0020]

In such a pressure equalizing condition setting device of the pressure equalizing cushion device, the generated hydraulic pressure is detected by the hydraulic pressure detecting means while changing the initial hydraulic pressure by the initial hydraulic pressure changing means.
The change amount of the generated oil pressure accompanying the change of the initial oil pressure is calculated by the change amount calculating means. Then, it is determined by the determining means whether or not the amount of change is equal to or less than a predetermined value, in other words, whether or not the generated oil pressure is substantially constant regardless of the change in the initial oil pressure. On the basis of the equalized initial hydraulic pressure region, the setting means obtains and sets equalizing conditions relating to the hydraulic pressure of the hydraulic cylinder, that is, the equalized initial hydraulic pressure Po and / or the equalized pressure generating hydraulic pressure PXo. The equalizing initial oil pressure Po may be set within the above equalizing initial oil pressure region, whereby the wrinkle pressing load can be evenly distributed to the cushion pins during the press working. Further, the equalized pressure generation oil pressure PXo may be set to the generated oil pressure in the equalization initial oil pressure region.
For example, by correcting the initial oil pressure so that the generated oil pressure substantially matches the equalized pressure generation oil pressure PXo, or by monitoring whether or not the generated oil pressure during the actual press working substantially matches the equalized pressure generation oil pressure PXo, It is possible to judge a press failure caused by foreign matter biting in the hydraulic cylinder or the like.

That is, the pressure equalizing condition setting device is a device for setting the pressure equalizing condition by using the diagnostic method of the first invention.
The part that detects the generated oil pressure while changing the initial oil pressure,
The part corresponding to the oil pressure detecting step of the first invention, in which the amount of change in the generated oil pressure accompanying the change in the initial oil pressure is determined, and whether or not the amount of change is equal to or less than a predetermined value, is the first part.
This corresponds to the determining step of the invention.

[0022]

As described above, in the third invention as well, as in the first invention, the average driving dimension Xav, the pressure receiving area As, the bulk modulus K, the oil amount V, etc. The pressure equalization condition relating to the hydraulic pressure of the hydraulic cylinder is set simply and accurately without calculating according to the formula or the formula (2), thereby reducing press failure due to uneven wrinkle holding load. In addition, the detection of the generated hydraulic pressure, the calculation of the change amount, the determination of the equalizing initial hydraulic pressure area, and the setting of the equalizing condition based on the equalizing initial hydraulic pressure area are automatically performed. An erroneous setting of the pressure equalization condition due to a user's operation error or the like is favorably avoided.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. In FIG. 3, the bolster 12 to which the punch mold 10 is attached is disposed on the base 16 via the press carrier 14, while the press slide 20 to which the die 18 is attached is driven up and down by a drive mechanism (not shown). It has become. The bolster 12 is provided with a large number of through holes 24 for disposing the cushion pins 22. Below the bolster 12, a cushion pad 2 for supporting the cushion pins 22 is provided.
6 are provided. The cushion pins 22 support a wrinkle holding ring 28 that is provided together with the punch mold 10, and are provided in an arbitrary number at predetermined positions predetermined according to the shape of the wrinkle holding ring 28. . The cushion pad 26 includes a number of hydraulic cylinders 30 corresponding to the through holes 24, and the lower ends of the cushion pins 22 are respectively brought into contact with the piston rods of the hydraulic cylinder 30. The punch type 1
0 corresponds to the lower press die, the die 18 corresponds to the upper press die, and the wrinkle press ring 28 corresponds to the wrinkle press die.

The cushion pad 26 is disposed in the press carrier 14 so as to be vertically movable, and is constantly urged upward by an air cylinder 32. The pressure chamber of the air cylinder 32 is communicated with an air tank 34, and the air tank 34 is supplied with pressure air of a predetermined air pressure Pa from an air pressure source 36 via an air regulator 38. I have. This air pressure Pa is set according to the wrinkle holding load. That is, when the die 18 is lowered together with the press slide 20, while pressing the peripheral portion of the work 40 between the die 18 and the wrinkle holding ring 28,
When the air cylinder 32 is pushed down via the wrinkle holding ring 28, the cushion pin 22, the hydraulic cylinder 30, and the cushion pad 26 when the drawing is performed between the die 18 and the punch 10, the air pressure is reduced. Pa
Is applied to the wrinkle holding ring 28.

In this embodiment, the wrinkle holding load applying means 42 is constituted by including the air cylinder 32, the air tank 34, the air pressure source 36, and the air regulator 38. A pressure equalizing cushion device 44 that includes the cylinder 30, the cushion pin 22, and the like and applies a predetermined wrinkle holding load to the wrinkle holding ring 28 substantially uniformly is configured.

The hydraulic chambers of the plurality of hydraulic cylinders 30
While being communicated with each other via a pipe 46,
The pipe 46 is connected to a pipe 50 via a flexible tube 48.
The hydraulic oil pumped from a tank 54 by an air-driven hydraulic pump 52 is supplied through a check valve 56. A hydraulic control circuit 60 having a relief valve and the like controlled by a control unit 58 is connected to the pipe 50 so that hydraulic control is performed. This hydraulic control is to control the hydraulic pressure of the hydraulic cylinder 30 at the time of non-press working to be a preset equalizing initial hydraulic pressure Po. The control unit 58 is provided with a hydraulic pressure sensor 62 connected to the pipe 50. Via the amplifier 64 and the A / D converter 66, a signal representing the oil pressure P in the pipe 50 or the hydraulic cylinder 30 is taken in. Control unit 58
Is configured to include a microcomputer having a CPU, a RAM, a ROM, and the like, and perform the above-described hydraulic control by performing signal processing according to a predetermined program, as well as the equalizing initial hydraulic pressure Po and the equalizing pressure generating hydraulic pressure. PXo
Is set, and the hydraulic pressure PX generated during press working is monitored. A display / operation panel 68 is connected to the control unit 58, and a test hit switch signal SS indicating that the test hit switch of the press machine has been turned ON, and the press slide 20 has a substantially lower end (bottom dead center or lower). Bottom dead center signal SD indicating that a short time has been reached is supplied. The display / operation panel 68 includes the display and operation switches shown in FIG. 4, and the oil pressure P is displayed on the display 70.

The setting of the equalizing initial oil pressure Po and the equalizing pressure PXo is performed according to the flowchart of FIG. In FIG. 5, in step S1, it is determined whether or not the changeover switch 72 of the display / operation panel 68 has been switched to "automatic" indicating the automatic equalization setting. In step S2, the operation preparation of the display / operation panel 68 is also performed. It is determined whether or not the push button 74 has been pressed. When the changeover switch 72 is switched to “automatic” and the operation preparation push button 74 is pressed, an equalizing initial oil pressure P _n (n = 1 to 10) is set in step S3. Equalization initial oil pressure P _n is, 200 kgf from 20kgf / cm ² / cm ²
Are stored in advance at intervals of 20 kgf / cm ^{2 in} the range up to and set in order from the high pressure side. Note that 1 kgf / cm ² is about 9.8 × 10 ⁴ Pa (Pascal).

[0028] In the next step S4, the hydraulic pressure P average is set at step S3 pressurization initial oil pressure P _n of the hydraulic circuit in the non-pressing, i.e. first 200 kgf /
The hydraulic pump 52 and the hydraulic control circuit 60 are controlled while reading the hydraulic pressure signal from the hydraulic pressure sensor 62 so that the pressure becomes cm ² . When the hydraulic pressure P ≒ _Pn , the buzzer sounds in a predetermined pattern indicating preparation completion in step S5, and in step S6, it is determined whether or not the test hit switch of the press machine has been turned ON. When the test hit switch is turned on by the worker who hears the buzzer and the test hit switch signal SS is supplied, the buzzer is stopped in step S7, and in the next step S8, the press machine is turned on once by turning on the test hit switch. PX generated during press working
While reading and storing _n , it is displayed on the display 76 of the display / operation panel 68. Since the hydraulic pressure change during the press working involves vibration due to impact as shown in FIG. 6, in this embodiment, the hydraulic pressure P near the bottom dead center SL where the vibration is reduced, that is, the bottom dead center signal from the press machine is used. SD is to read the hydraulic pressure P represented by the oil pressure signal of the pressure sensor 62 when it is supplied as a hydraulic pressure generated PX _n. Note that another hydraulic pressure value such as a maximum value, a minimum value, or an average value of the hydraulic pressure P up to the bottom dead center SL can be used as the generated hydraulic pressure.

In the next step S9, the current hydraulic pressure P
X PX = | P the change amount between X _n and the previous generated hydraulic pressure PX _n-1
Xn- PXn _-1 |, and in step S10,
It is determined whether or not the change amount ΔPX is equal to or smaller than a predetermined determination value α. The decision value alpha, intended for regardless generating hydraulic pressure PX _n is equal to or substantially constant with a change in the pressure equalization initial oil pressure P _n, in consideration of variations or hydraulic detection error of the hydraulic pressure generated PX _n For example, a value of about 5 kgf / cm ² is set. When the change amount ΔPX ≦ α, the flag F is set to “1” in step S11, and then, in step S12, the equalizing initial hydraulic pressure P is displayed on the display / operation panel 68.
10 pressure equalizing initial oil pressure area indicator lamps provided for every _n
8, the lamp corresponding to the previous equalization initial oil pressure P _n-1 is turned on. If the change amount ΔPX> α, it is determined in step S13 whether the flag F = 1 or not.
If = 1, the flag F is set to "0" in step S14, and then step S12 is executed. Subsequent step S1
In 5, it is determined whether or not the equalized initial oil pressure P _n = 20 kgf / cm ² , in other words, whether or not the detection of the generated oil pressure PX _n has been completed for all the equalized initial oil pressures P _n .
Until P _n = 20 kgf / cm ² , the execution of step S3 and subsequent steps is repeated while changing the setting of the equalizing initial oil pressure P _n . The equalizing initial oil pressure _Pn is 200 kgf / c.
The first cycle in m ^2, Step S9~S14
Is omitted, and step S15 is executed following step S8.

[0030] Figure 7 by step S3 following execution is repeated, a graph showing an example of the equalization initial oil pressure P _n detected generated hydraulic pressure PX _n for each, pressure equalization initial oil pressure P ₄ = Generated hydraulic pressure PX at 140 kgf / cm ²
₄ is 200 kgf / cm ² , equalizing initial oil pressure P ₅ = 12
A hydraulic pressure generated PX ₅ at the time of 0kgf / cm ² is 198kgf
/ Cm ² . Therefore, the equalizing initial oil pressure P ₅ = 12
In the case of 0 kgf / cm ^2, the amount of change ΔPX = | PX ₅
-PX ₄ | = 2 kgf / cm ² , the determination in step S10 becomes YES, and in step S12, the lamp of the previous equalization initial oil pressure P ₄ = 140 kgf / cm ² is turned on. Also in the case of the equalizing initial oil pressure P ₆ = 100 kgf / cm ² and the equalizing initial oil pressure P ₇ = 80 kgf / cm ² , similarly, the determination in step S10 is YES and the respective steps S
In step 12, the equalizing initial oil pressure P ₅ = 120 kgf / cm ²
The lamp of the equalizing initial oil pressure P ₆ = 100 kgf / cm ² is turned on. Equalizing initial oil pressure P ₈ = 60kgf / cm
^In the case of ² , the change amount ΔPX = | PX ₈ −PX ₇ |> α
In step S10, the determination in step S10 is NO, but since the flag F = 1 in the previous cycle, the determination in step S13 is YES, and in step S12, the ramp of the equalizing initial oil pressure P ₇ = 80 kgf / cm ² is turned on. Light. The equalizing initial hydraulic pressure area display lamp 78 in FIG. 4 shows the lighting state (hatched line) in this case.

Here, the lighting oil pressure area of the equalizing initial oil pressure area display lamp 78, in other words, the equalizing initial oil pressure P _n
C region of FIG. 7 in the region of the equalization initial oil pressure P _n variation ΔPX in spite generating hydraulic PX _n is less changed, FIG. 1
Similarly to the area C, the cushion pins 22 are disposed and the pistons of all the hydraulic cylinders 30 involved in the wrinkle holding are in a neutral state at the time of press working, which corresponds to an initial pressure equalizing hydraulic area. . The hydraulic pressure range and interval of the equalizing initial oil pressure _Pn set in the step S3 can determine the equalizing initial oil pressure region regardless of the wrinkle holding load and the difference in the number of cushion pins 22 used depending on the type of press working. As described above, it is predetermined in consideration of the number of hydraulic cylinders 30, the pressure receiving area, the piston stroke, the setting range of the wrinkle holding load, and the like. Depending on wrinkles using the number of pressing load and the cushion pins 22, for example, (1) the expected average seek圧初stage hydraulic, hydraulic range equalization initial oil pressure P _n to include the expected average圧初life hydraulic accordance formula Or intervals may be set.

For example, if the length of the cushion pin 22 has a large variation or the piston stroke of the hydraulic cylinder 30 is small, some of the hydraulic cylinders 30 are not operated and other hydraulic cylinders are not operated. In the case of the body thrust state, when the equalizing initial oil pressure region cannot be clearly distinguished, for example, when the equalizing initial oil pressure region does not appear, or when a plurality of equalizing initial oil pressure regions appears, the equalizing cushion device 44 is used. This means that the pressure equalizing cushion device 44 can be determined from the lighting state of the pressure equalizing initial oil pressure area display lamp 78. The equalizing initial oil pressure area display lamp 78 does not light at all,
An abnormal display may be performed when the lamps are lit separately. The changeover switch 7
If “2” is set to “each”, the equalizing initial oil pressure setting dial 8
Since 0 can be set arbitrarily pressure equalization initial oil pressure P _n is manually operated, and by confirming the display unit 76 to generate hydraulic pressure PX _n during press working of the case, finely pressure equalization initial oil pressure P _n or examine changes in the hydraulic pressure generated PX _n while changing, or can locate manually equalizing圧初stage hydraulic region.

Returning to FIG. 5, when the determination in step S15 is YES, step S16 is next executed to determine whether or not the flag F = 1. If the flag F = 1,
In step S17, the lamp of the current pressure equalization initial oil pressure P _n , that is, P ₁₀ = 20 kgf / cm ² in this embodiment is turned on, the flag F is set to “0” in step S18, and then step S19 is executed. If the flag F = 0, step S19 is executed following step S16.
These steps correspond to the equalization initial oil pressure P ₉ = 40 kgf
And a hydraulic pressure generated PX ₉ when the / cm ^2, the pressure-equalizing initial oil pressure P ₁₀
= 20 kgf / cm ² when the change amount ΔPX from the generated oil pressure PX ₁₀ is equal to or smaller than the judgment value α, to turn on the lamp of the equalization initial oil pressure P ₁₀ .

[0034] At step S19, the average value of the equalization initial oil pressure P _n of the lighting part of the equalizing圧初stage hydraulic area display lamp 78, and sets the average value as equalizing圧初life hydraulic Po. For example, in the case of the lighting state shown in FIG.
(00 + 120 + 140) / 4 = 110 kgf / cm ² is set as the equalizing initial oil pressure Po. Step S
In 20, the average value of the hydraulic pressure generated PX _n in equalization initial oil pressure P _n of the lighting part of the equalizing圧初stage hydraulic area display lamp 78, and sets the average value as equalizing pressure generating hydraulic PXO. For example, when the relationship between the pressure equalization initial oil pressure P _n and the generated hydraulic pressure PX _n is shown in FIG. _{7, (PX 4 + PX 5 +} PX 6 +
PX ₇ ) / 4 = (200 + 198 + 202 + 201) /
4 200 kgf / cm ² is set as the pressure equalizing pressure PXo. Both the equalizing initial oil pressure Po and the equalizing pressure oil pressure PXo are equalizing conditions for the hydraulic pressure of the hydraulic cylinder 30.

With the above, the setting of the equalizing initial oil pressure Po and the equalizing pressure generating pressure PXo is completed. During the actual press working, for example, as shown in FIG. The hydraulic pump 52 and the hydraulic control circuit 60 are controlled so that the initial hydraulic pressure Po is attained. Thereby, at the time of press working, all the hydraulic cylinders 30 involved in the wrinkle presser are held in a neutral state, and the drawing process is performed in a state where the surface pressure distribution of the wrinkle presser is substantially constant. FIG.
As shown in the figure, the generated oil pressure PX is read and compared with the equalized pressure generation oil pressure PXo. If the generated oil pressure PX is not PXo, the abnormality display lamp 82 of the display / operation panel 68 is turned on or a predetermined pattern indicating the abnormality is displayed. Sound a buzzer,
The operator is notified of the abnormality of the press machine. The initial hydraulic pressure during non-press working can be corrected so that the generated oil pressure PX substantially matches the equalized pressure generated oil pressure PXo, and the equalized pressure generated oil pressure PXo, the pressure receiving area As of the hydraulic cylinder 30, the cushion pin 22 From the weight Wp, the number n used, and the weight Wr of the wrinkle holding ring 28, the wrinkle holding load Fs can also be obtained in accordance with the above equation (2).

Here, the press machine of this embodiment is
Together determine the hydraulic pressure generated PX _n and ten equalization initial oil pressure P _n predetermined occurrence changes the hydraulic PX _n seek small average圧初stage hydraulic region, the average pressure of the equalizing圧初life hydraulic region Hitoshi while the圧初stage hydraulic Po, the average oil pressure of the hydraulic pressure generated PX _n in average圧初life hydraulic area is the average pressure generating hydraulic PXO. For this reason, it is simpler and simpler than in the conventional case where the average run-in dimension Xav, the pressure receiving area As, the bulk modulus K, the oil amount V, and the like are calculated in accordance with the above-described equations (1) and (2). Precise pressure equalization Initial oil pressure Po
And the equalizing pressure oil pressure PXo can be obtained, and press failure due to uneven wrinkle holding load can be reduced, and any abnormality of the equalizing cushion device 44 can be determined from the lighting state of the equalizing initial oil pressure area display lamp 78. You can also judge. Further, the operator only performs a predetermined switch operation, the hydraulic pressure generated PX _n of detection and calculation of the change amount .DELTA.Px, determination of average圧初stage hydraulic region, and pressure-equalizing initial oil pressure Po and equalizing based on equalizing圧初stage hydraulic region Since the setting of the pressure generating oil pressure PXo is performed automatically, the burden on the operator is reduced, and erroneous setting due to an operator's operation error or the like is favorably avoided.

This embodiment is an embodiment of the first and third inventions. Steps S3, S4, and S8 executed by the control unit 58 correspond to a hydraulic pressure detection step, and steps S9, S10 , S12, and S
17 corresponds to a determination step. The oil pressure sensor 62 corresponds to an oil pressure detecting means, and a part of the series of signal processing by the control unit 58 that executes steps S3 and S4 constitutes an initial oil pressure changing means together with the oil pressure control circuit 60 and the oil pump 52. I have. Further, the part executing steps S8 and S9 corresponds to a change amount calculating means, the part executing step S10 corresponds to a determining means, and the part executing steps S12, S17, S19 and S20 corresponds to a setting means. I do.

In the region where the equalizing initial oil pressure _Pn is low, the influence of air mixed in the hydraulic oil causes
Sometimes equalization initial oil pressure P _n regardless generated hydraulic pressure PX _n to changing hardly changes. The data shown in FIG. 10 is an example, and the pressure equalization initial oil pressure P ₉ = 40 kgf / cm ² , P ₁₀
= 20 kgf / cm ² , the generated oil pressures PX ₉ and PX ₁₀ have substantially the same value. In this case, it is determined YES in step S10 in the above embodiment the pressure-equalizing initial oil pressure P ₁₀ = 20kgf / cm ² cycle, step S12, S
The execution of 17, among the display lamps 78 in the display and operation panel 68, also illuminates the lamp hydraulic P ₉ = 40kgf / cm ² and P ₁₀ = 20kgf / cm ^2, Hitoshi圧初life hydraulic Po and the pressure equalizing hydraulic pressure generated PXo may be set incorrectly.

The embodiment shown in FIGS. 11 to 14 is designed to prevent an erroneous determination from being made in a region where the equalizing initial oil pressure _Pn is low as described above. I do. In the following embodiments, portions common to the above-described embodiments are given the same reference numerals, and detailed description is omitted.

In the flowchart of FIG. 11, after steps S1 to S8 having the same contents as those of the flowchart of FIG.
Is determined to be “0”. Since the flag F1 is initially set to "0", the flag F1 is 0 in the first cycle of executing the step S21, and then the step S9 is executed to calculate the change amount .DELTA.PX. It is determined whether or not the amount of change ΔPX is equal to or smaller than a determination value α. Then, when the change amount ΔPX ≦ α,
In step S22, the comparison reference oil pressure PY is set, and in step S23, the flags F1 and F2 are set to "1". Comparison reference hydraulic pressure PY is the foundation for calculating the amount of change in hydraulic pressure generated PX _n in the subsequent cycle,
For example this hydraulic pressure generated PX _n or previous occurrence hydraulic PX
_n-1, or an average value of it, such as _{(PX n + PX n-1} ) / 2
Etc. are set. After that, step S12 is executed, and among the equalizing initial hydraulic pressure area display lamps 78 on the display / operation panel 68, the lamp corresponding to the previous equalizing initial hydraulic pressure P _n-1 is turned on.

If the determination in step S10 is YES and the flag F1 is set to 1 in step S23, in the subsequent cycle, step S24 follows step S21.
Do the following: In step S24, the amount of change ΔPY of the current generated oil pressure PX _n with respect to the comparison reference oil pressure PY =
| PX _n -PY | is calculated, and in step S25,
It is determined whether or not the amount of change ΔPY is equal to or smaller than a predetermined determination value α. The determination value α may be set to a value different from the determination value α in step S10. And
If the change amount ΔPY ≦ α, steps S23 and S12
Is performed, and the lamp corresponding to the previous equalization initial oil pressure P _n-1 is turned on. If the change amount ΔPY> α, it is determined in step S26 whether or not the flag F2 = 1.
If F2 = 1, the flag F2 is set to "0" in step S27, and then step S12 is executed.
If it is 0, the steps from step S15 are executed. Incidentally, Step S16 'the flag F2 is determined whether "1", light the current equalization initial oil pressure P _n ie P ₁₀ = 20kgf / cm ² lamp in step S17, in the case of F2 = 1 I do. In step S18 ', the flag F
1 and F2 are each set to “0”.

In this embodiment, first, when the determination in step S10 is YES, that is, when the hydraulic pressure change amount ΔPX ≦
Generated hydraulic pressure PX _n when α has been reached or previous generated hydraulic pressure P
X _n-1 or an average value thereof is set as the comparison reference oil pressure PY.
Because by comparing the Y and generating hydraulic pressure PX _n is adapted to perform pressure equalization determination, if the hydraulic pressure generated PX _n such as FIG. 10 is detected, the hydraulic pressure generated PX ₄ or PX _5, or even like the average value of the comparison reference hydraulic pressure PY, it is determined that the pressure equalization initial oil pressure P ₄ to P ₇ in the region C NomigaHitoshi圧初life hydraulic region. In other words, even when the generated oil pressures PX ₉ and PX ₁₀ are substantially equal, the change amount ΔPY with respect to the comparison reference oil pressure PY is large, so that the region of the equalized initial oil pressures P ₉ and P ₁₀ is erroneously determined to be the equalized initial oil pressure region. There since the it is not to be equalizing圧初life hydraulic Po and the pressure equalizing hydraulic pressure generated PXo is equalized initial oil pressure P _n region C, are correctly set on the basis of the generated hydraulic pressure PX _n.

This embodiment also constitutes an embodiment of the first invention and the third invention. Steps S3, S4 and S8 correspond to a hydraulic pressure detection step, and steps S9, S10, S12 and S8.
17, S22, S24, and S25 correspond to the determination step. Further, the hydraulic pressure sensor 62 corresponds to a hydraulic pressure detecting means,
The part that executes steps S3 and S4 constitutes an initial hydraulic pressure changing unit together with the hydraulic control circuit 60 and the hydraulic pump 52. Further, the steps for executing steps S8, S9, S22, and S24 correspond to the change amount calculating means, and the steps for executing steps S10, S25 correspond to the determining means, and execute steps S12, S17, S19, and S20. The part to be performed corresponds to the setting means.

FIG. 12 is a flowchart of another embodiment in which the steps S21 to S27 in the flowchart of FIG. 11 are similarly provided.
After reading and storing the generated hydraulic pressure PX _n at step S,
9, the change amount ΔPX is calculated, and at step S10
It is determined whether the change amount ΔPX is equal to or less than the determination value α in
If the change amount ΔPX ≦ α, it is determined in step S21 whether the flag F1 is “0”. Since the flag F1 is initially set to "0", F1 = 0 in the first cycle of executing the step S21 and the subsequent steps, and subsequently the step S22 and the subsequent steps are executed. In step S22, in the same manner as in Example Set comparison reference hydraulic PY, step S23, the flag F1, F2 respectively to "1", corresponding to the pressure equalizing initial oil pressure P _n-1 of the previous In step S12 Turn on the lamp. The determination in step S10 is Y
If ES is set and the flag F1 is set to 1 in step S23, steps S24 and subsequent steps are executed subsequent to step S21 in the subsequent cycle. If the amount of change ΔPX> α in step S10, steps S26 and subsequent steps are executed.

That is, in this embodiment, the variation ΔPX ≦
Only when α is set, the steps S21 and subsequent steps are executed, and once the steps S22 and the subsequent steps are executed to set the comparison reference oil pressure PY, the steps S21 and the subsequent steps are executed after the step S21, thereby obtaining the comparison reference oil pressure PY. We perform pressure equalization determination by comparing the generated hydraulic pressure PX _n and. Therefore, even if the change amount ΔPX ≦ α, the change amount ΔPY ≦ α
Otherwise, the equalization determination is NO, and the same effects as in the embodiment of FIG. 11 can be obtained.

In the embodiment of FIG. 13, after executing steps S1 to S10 in the same manner as in the flowchart of FIG.
If the change amount ΔPX ≦ α, the flag F1 is set to “1” in step S28, and step S12 is executed to turn on the lamp corresponding to the previous pressure equalization initial oil pressure P _n−1 , while the change amount ΔPX> In the case of α, it is determined whether or not the flag F1 is “1” in step S29, and F1 =
If it is 1, the flag F1 is set to "0" and the flag F2 is set to "1" in step S30, and then step S12 is executed.
In step S31 following step S12, the flag F2
Is determined to be “1”, and if F2 = 0, the steps from step S15 are performed. However, if F2 = 1, that is, the determination in step S10 is once made YES, then becomes NO, and the processing proceeds to step S29. Subsequently, when step S30 is executed, step S18 "and subsequent steps are immediately executed, and a series of processing ends.
The process is executed when the determination in step S10 is affirmed when the equalizing initial oil pressure P ₁₀ = 20 kgf / cm ² or when the equalizing initial oil pressure region cannot be detected at all. In step S16 ″, the flag F1 is set to “ 1 "or not, and F
Lights up the current equalization initial oil pressure P _n ie P ₁₀ = 20kgf / cm ² lamp step S17 in the case of 1 = 1. In step S18 ", the flags F1, F2
Are set to “0”.

That is, in this embodiment, once the determination in step S10 becomes YES and the equalizing initial hydraulic pressure region is detected, the subsequent equalizing determination is stopped when the pressure is out of the equalizing initial hydraulic pressure region. Therefore, erroneous pressure equalization determination in a region where the pressure equalizing initial oil pressure _Pn is low is prevented. For example, occur if the oil pressure PX _n is detected, the region C NomigaHitoshi圧初life hydraulic area of the hydraulic pressure generated first equalized early PX _n of variation ΔPX is small hydraulic P ₄ to P ₇ as FIG. 10 It is determined that the equalizing initial oil pressure P ₈ = 60 kg
In the cycle at f / cm ² , the determination in step S10 is N
When it becomes O, the subsequent equalization determination is stopped, and the equalizing initial oil pressure Po and the equalizing pressure PXo are set based on the data of only the equalizing region C.

This embodiment also constitutes an embodiment of the first and third inventions, and the step S is performed similarly to the first embodiment.
Steps S3, S4, and S8 correspond to a hydraulic pressure detection step, and steps S9, S10, S12, and S17 correspond to a determination step. Further, the oil pressure sensor 62 corresponds to an oil pressure detecting unit, and a portion that executes steps S3 and S4 constitutes an initial oil pressure changing unit together with the hydraulic control circuit 60 and the hydraulic pump 52. Further, the part that executes steps S8 and S9 corresponds to the change amount calculating means, and the part that executes step S10 corresponds to the determining means, and steps S12 and S1
The part that executes steps S7, S19, and S20 corresponds to a setting unit.

FIG. 14 is a flowchart of another embodiment in which steps S28 to S31 in the flowchart of FIG. 13 are similarly provided. Step S31 of determining whether or not flag F2 is "1" is replaced by step S8.
When the flag F2 = 1, the equalization determination in step S9 and subsequent steps is stopped. However, by executing step S15 and subsequent steps, the subsequent equalization initial hydraulic pressure P
_{Also for n} , the generated hydraulic pressure PX _n is detected. That is, lighting of the equalizing initial oil pressure area display lamp 78, equalizing initial oil pressure Po and equalizing pressure oil pressure PX
The setting of o is the same as that of the embodiment of FIG. 13 described above, however, the generated oil pressure PX _n is also detected for the equalized initial oil pressure P _n after deviating from the initial equalized initial oil pressure region, and the display 76 The pressure equalization initial oil pressure P
The relationship between _n and the generated oil pressure PX _n can be confirmed to the end.

In each of the above embodiments, the pressurized oil pressure P is changed by operating the press for one cycle while changing the initial oil pressure _Pn.
Xn is detected and pressure equalization judgment is performed. However, in the wrinkle holding state where the die 18 presses the wrinkle holding ring 28, the pressure is generated while changing the amount of hydraulic oil in the hydraulic cylinder 30. The pressure equalization can also be determined by detecting the hydraulic pressure PX. FIG. 15 shows an example of a pressure equalizing cushion device capable of diagnosing the pressure equalizing region in this manner. A constant flow rate discharge valve for allowing the hydraulic fluid in the hydraulic circuit communicating with the hydraulic cylinder 30 to flow out at a constant flow rate into the pipe 50. 90 is connected, and the opening / closing is controlled in accordance with a signal from the control unit 58, and the pressure equalization diagnosis is performed according to the flowchart of FIG. In this case, the display / operation panel 68 does not require the equalizing pressure initial oil pressure area display lamp 78.

In FIG. 16, when the changeover switch 72 is switched to "automatic" indicating automatic equalization setting and the operation preparation push button 74 is pressed, step R3 is executed and the hydraulic pressure of the hydraulic circuit during non-press working is executed. P is a predetermined set oil pressure Pmax, for example, 200 kgf / cm
^The hydraulic pump 52 and the hydraulic control circuit 60 are controlled while reading the hydraulic pressure signal from the hydraulic pressure sensor 62 so as to be about ^two . Next, in step R4, the press slide 20 is lowered to a predetermined lowering position. In this state, the constant flow discharge valve 90 is opened in step R5 to discharge the hydraulic oil in the hydraulic circuit at a constant flow rate. R
At step 6, the generated hydraulic pressure PX is read and stored. The lowered position of the press slide 20 is a position where at least the wrinkle pressing ring 28 is pressed to be in a wrinkle pressing state, and is, for example, a bottom dead center position to which the bottom dead center signal SD is supplied. In step R7, the generated oil pressure PX is reduced to a predetermined lower limit value PXmi.
n, for example, it is determined whether the pressure has dropped to about 150 kgf / cm ² , and step R6 is repeatedly executed at a predetermined cycle time until PX ≦ PXmin. And P
When X ≦ PXmax, at step R8, the constant flow discharge valve 9
0 is closed, and in step R9, a pressure equalizing region is determined from the data of the generated hydraulic pressure PX. The above set hydraulic pressure Pmax, lower limit value P
Xmin may be set to a fixed value in advance, but it can be set arbitrarily by an operator using a setting switch or the like, or can be set according to the formula (1) or the like according to the wrinkle holding load and the number of cushion pins 22 used. It is also possible to obtain the expected initial pressure for equalizing pressure and the oil pressure for generating the expected equalizing pressure according to the equation (2), and set the set oil pressure Pmax and the lower limit value PXmin based on the oil pressure values.

Here, the generated oil pressure PX detected in step R6 changes as the hydraulic oil flows out, for example, as shown in FIG. On the other hand, the change in the amount of hydraulic oil in the hydraulic circuit communicating with the hydraulic cylinder 30 is substantially the same as changing the equalizing initial oil pressure _Pn in each of the above-described embodiments. In the pressure equalizing region where the 30 pistons are in the neutral state, the generated oil pressure PX hardly changes, only the piston position changes with the change in the amount of hydraulic oil.
Therefore, in step R9, the region where the generated oil pressure PX hardly changes regardless of the outflow of hydraulic oil, that is, the region Ct in which the change width of the generated oil pressure PX sequentially detected in step R6 is equal to or less than a predetermined value is equalized. It is sufficient to judge the area as, for example, the amount of change ΔPX or ΔP
It is determined by calculating Y or the like. When the pressure equalizing area Ct cannot be determined or a plurality of pressure equalizing areas Ct appear, it indicates some abnormality of the pressure equalizing cushion device 44, and an abnormal display lamp, a buzzer, or the like indicates an abnormal display. It is supposed to do.

In the next step R10, the above step R
The generated oil pressure PX in the equalization region Ct determined in step 9 is set to the equalized pressure generation oil pressure PXo, and in step R11, the press slide 20 is returned to the top dead center to complete a series of equalization diagnosis processing. By setting the equalizing pressure generating oil pressure PXo in step R10, the initial oil pressure Po is adjusted so that the generated oil pressure PX ≒ PXo at the time of the actual press working performed thereafter, or the generated oil pressure PXo as shown in FIG. And monitor PX.

In this embodiment, as in the above embodiments, the average driving dimension Xav, the pressure receiving area As, the bulk modulus K,
Simple and accurate equalizing pressure generation hydraulic pressure PXo is calculated without using oil amount V or the like according to the above formulas (1) and (2).
And an abnormality diagnosis of the equalizing cushion device 44 can be performed. In addition, since the constant flow rate discharge valve 90 is opened in a predetermined wrinkle holding state and the generated oil pressure PX is detected while the hydraulic oil in the hydraulic circuit flows out, the pressure equalizing region is determined from the change in the generated oil pressure PX. Compared to the case of operating the press while changing the initial oil pressure as in the above-described embodiment to perform the equalization diagnosis, the equalization region can be diagnosed more quickly, and it is not necessary to turn on the test hitting switch one by one. Diagnosis of pressure equalization is performed automatically.

This embodiment is an embodiment of the second invention. Step R4 executed by the control unit 58 corresponds to a wrinkle holding step, steps R5 and R6 correspond to a hydraulic pressure detecting step, and step R9 is executed. Corresponds to the determination step.

Although several embodiments of the present invention have been described in detail with reference to the drawings, the present invention can be implemented in other embodiments.

For example, in the above-described embodiment, the buzzer sounds after the hydraulic pressure is adjusted in step S4, and the operator manually turns on the test hitting switch of the press machine. It can be configured to perform pressing.

[0058] The although the embodiment was so inform the equalizing圧初life hydraulic area lighting of the lamp 78, the amount of change ΔPX is adapted to store the following equalization initial oil pressure P _n determined value α However, the lighting display by the lamp 78 is not always necessary.

Further, the equalizing initial oil pressure _Pn and the generated oil pressure PX
_In order to clearly inform the worker of the relationship with _n , a two-dimensional graph as shown in FIG. 7 can be displayed on a liquid crystal display or the like. It is also possible to obtain and set the initial oil pressure Po and the equalizing pressure oil pressure PXo. Also in the embodiments of FIGS. 15 to 17, it is possible to display a two-dimensional graph as shown in FIG. 17 on a liquid crystal display or the like.

In the above embodiment, the equalizing initial oil pressure _Pn is set from the high pressure side. However, the equalizing initial oil pressure _Pn is set from the low pressure side, that is, 20 kgf / cm ^2. You can do it. The maximum and minimum values of the equalizing initial oil pressure _Pn and the changed oil pressure interval can be set manually.

In the above embodiment, the equalizing initial oil pressure Po and the equalizing pressure PXo are both calculated and set as equalizing conditions. However, only one of them is determined and set. It may be.

In the embodiments shown in FIGS. 15 to 17, the hydraulic oil is discharged at a constant flow rate by the constant flow discharge valve 90. It is also possible to detect an outflow oil amount and perform a pressure equalization diagnosis from the relationship between the outflow oil amount and the generated oil pressure PX. The generated oil pressure PX may be detected by causing the operating oil to flow out intermittently by a constant oil amount.

It is also possible to detect the generated oil pressure PX while supplying the hydraulic oil from the low pressure state by the hydraulic pump 52 to perform the pressure equalization diagnosis.

Before returning the press to the top dead center in step R11, hydraulic oil is supplied by the hydraulic pump 52 until the oil pressure P reaches the equalizing pressure PXo set in step R10. It is also possible to return to the dead center and detect the equalizing initial oil pressure Po. The outflow is stopped when there is no change in the generated oil pressure PX regardless of the outflow of hydraulic oil,
The generated oil pressure PX at that time may be used as the equalized pressure generation oil pressure PXo, and the press may be returned to the top dead center to detect the equalized initial oil pressure Po.

In the above-described embodiment, the punch die 10 is arranged on the base 16 via the press carrier 14. However, a punch machine in which the punch die 10 is fixedly mounted on the base 16 is used. The present invention can be applied in the same manner, and the arrangement of the punch mold 10 can be appropriately changed.

Although the wrinkle holding load applying means 42 in the above embodiment applies the wrinkle holding load based on the air pressure, the wrinkle holding load may be applied by a relief pressure of a hydraulic cylinder, a spring or the like. it can.

Although not specifically exemplified, the present invention can be embodied with various modifications and improvements based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a relationship between an initial oil pressure and a generated oil pressure of a pressure equalizing cushion device.

FIG. 2 is a diagram corresponding to a claim of the third invention.

FIG. 3 is a view showing a configuration of a press machine which can preferably carry out the first invention and includes a pressure equalizing condition setting device of a pressure equalizing cushion device according to an embodiment of the third invention.

4 is a view showing a display / operation panel of a pressure equalizing cushion device provided in the press machine of FIG. 3;

FIG. 5 is a flowchart illustrating an operation when setting an equalizing initial oil pressure Po and an equalizing pressure oil pressure PXo of the equalizing cushion device in the press machine of FIG. 3;

6 is a diagram illustrating the detection position of the hydraulic pressure generated PX _n read in S8 in FIG.

FIG. 7 shows an equalizing initial oil pressure P according to the flowchart of FIG.
An example of a hydraulic pressure generated PX _n detected when setting the o and the pressure equalizing hydraulic pressure generated PXo illustrates the relationship between the pressure equalization initial oil pressure P _n.

8 is a flowchart showing a part for controlling an initial oil pressure of a pressure equalizing cushion device when actually performing press working in the press machine of FIG. 3;

FIG. 9 is a flowchart showing a part for monitoring the generated oil pressure of the pressure equalizing cushion device when actually performing the press working in the press machine of FIG. 3;

10 is a diagram showing another example of the relationship between the generated oil pressure PX _n and the equalized initial oil pressure P _n detected when the equalizing initial oil pressure Po and the equalizing pressure generating oil pressure PXo are set according to the flowchart of FIG. 5; It is.

FIG. 11 is a flowchart illustrating another embodiment of the first invention and the third invention.

FIG. 12 is a flowchart for explaining still another embodiment of the first invention and the third invention.

FIG. 13 is a flowchart for explaining still another embodiment of the first invention and the third invention.

FIG. 14 is a flowchart for explaining still another embodiment of the first invention and the third invention.

FIG. 15 is a view showing a configuration of a press machine provided with a pressure equalizing cushion device capable of suitably implementing the second invention.

FIG. 16 is a flowchart illustrating an operation when performing a pressure equalization diagnosis of the pressure equalizing cushion device in the press machine of FIG. 15;

17 is a diagram illustrating a change characteristic of a generated hydraulic pressure PX detected when performing pressure equalization diagnosis according to the flowchart of FIG. 16;

[Explanation of symbols]

10: Punch type (press lower type) 18: Die type (press upper type) 22: Cushion pin 26: Cushion pad 28: Wrinkle holding ring (Wrinkle holding type) 30: Hydraulic cylinder 40: Work 42: Wrinkle holding load applying means 44: Equalizing cushion device 52: Hydraulic pump 58: Control unit 60: Hydraulic control circuit 62: Hydraulic sensor (hydraulic detecting means) 90: Constant flow discharge valve Steps S3, S4, S8: Hydraulic pressure detecting step S9, S10, S12 , S17: judgment step S3, S4: initial oil pressure change means Step S8, S9: change amount calculation means Step S10: judgment means Step S12, S17, S19, S20: setting means Steps S9, S10, S12, S17, S22, S2
4, S25: Judgment step Steps S8, S9, S22, S24: Change amount calculation means Step S10, S25: Judgment means Step R4: Wrinkle holding step R5, R6: Oil pressure detection step R9: Judgment step

Claims (3)

(57) [Claims] 1. A cushion pad to which a wrinkle pressing load is applied by a wrinkle pressing load applying means, a plurality of hydraulic cylinders disposed on the cushion pad and having hydraulic chambers communicated with each other; A plurality of cushion pins which are respectively disposed and support the wrinkle presser die at the upper end, and the work is sandwiched between the press upper die and the wrinkle presser die by lowering the press upper die. When pressing is performed between the upper press die and the lower press die while pressing, the wrinkle pressing load applied to the wrinkle pressing die by the wrinkle pressing load applying means is applied to the plurality of cushion pins by the hydraulic cylinder. In a pressure equalizing cushion device of a press machine for distributing the wrinkle holding load substantially evenly, the hydraulic cylinder for distributing the wrinkle holding load substantially uniformly is provided. A method of diagnosing the pressure equalization condition relating to the hydraulic pressure of the hydraulic cylinder, wherein the initial hydraulic pressure of the hydraulic cylinder during the press working is changed while the initial hydraulic pressure of the hydraulic cylinder during the non-press working is changed. A hydraulic pressure detecting step of examining a relationship with the hydraulic pressure, and a determining step of determining, based on the relationship between the initial hydraulic pressure and the generated hydraulic pressure, an equalized initial hydraulic pressure region in which the generated hydraulic pressure is substantially constant regardless of a change in the initial hydraulic pressure. A method for diagnosing pressure equalization conditions of a pressure equalizing cushion device. 2. A cushion pad to which a wrinkle pressing load is applied by a wrinkle pressing load applying means, a plurality of hydraulic cylinders disposed on the cushion pad and having a hydraulic chamber communicated with each other; A plurality of cushion pins which are respectively disposed and support the wrinkle presser die at the upper end, and the work is sandwiched between the press upper die and the wrinkle presser die by lowering the press upper die. When pressing is performed between the upper press die and the lower press die while pressing, the wrinkle pressing load applied to the wrinkle pressing die by the wrinkle pressing load applying means is applied to the plurality of cushion pins by the hydraulic cylinder. In a pressure equalizing cushion device of a press machine for distributing the wrinkle holding load substantially evenly, the hydraulic cylinder for distributing the wrinkle holding load substantially uniformly is provided. A method for diagnosing the pressure equalization condition relating to the hydraulic pressure, comprising: a wrinkle pressing step of lowering the press upper die to a predetermined wrinkle pressing state in which the press upper die presses the wrinkle pressing die; A hydraulic pressure detecting step of detecting the hydraulic pressure of the hydraulic oil while changing the hydraulic pressure in the hydraulic circuit communicating with the hydraulic cylinder; and a region where the hydraulic pressure is substantially constant irrespective of the change in the hydraulic fluid oil amount. Determining a pressure equalizing region as a pressure equalizing region. 3. A cushion pad to which a wrinkle pressing load is applied by a wrinkle pressing load applying means, a plurality of hydraulic cylinders disposed on the cushion pad and having a hydraulic chamber communicated with each other; A plurality of cushion pins which are respectively disposed and support the wrinkle presser die at the upper end, and the work is sandwiched between the press upper die and the wrinkle presser die by lowering the press upper die. When pressing is performed between the upper press die and the lower press die while pressing, the wrinkle pressing load applied to the wrinkle pressing die by the wrinkle pressing load applying means is applied to the plurality of cushion pins by the hydraulic cylinder. In a pressure equalizing cushion device of a press machine for distributing the wrinkle holding load substantially evenly, the hydraulic cylinder for distributing the wrinkle holding load substantially uniformly is provided. An apparatus for setting pressure equalization conditions relating to the hydraulic pressure, a hydraulic pressure detecting means for detecting a hydraulic pressure of the hydraulic cylinder, and an initial hydraulic pressure changing means for changing an initial hydraulic pressure of the hydraulic cylinder during non-press working at predetermined intervals. A change amount calculating means for calculating a change amount of the generated oil pressure accompanying the change of the initial oil pressure by the initial oil pressure changing means based on the generated oil pressure of the hydraulic cylinder detected by the oil pressure detecting means at the time of press working; Determining means for determining whether or not the amount of change in the generated oil pressure calculated by the amount calculating means is equal to or less than a predetermined value; and equalizing pressure in which the amount of change in the generated oil pressure is determined to be equal to or less than the predetermined value. Setting means for obtaining and setting pressure equalizing conditions relating to the hydraulic pressure of the hydraulic cylinder based on the initial hydraulic pressure region. Conditions setting device.