JP2722936B2 - Automatic change device for wrinkle holding load of press machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press machine for drawing and, more particularly, to an automatic wrinkle holding load changing device for automatically changing a wrinkle holding load so that proper drawing is performed.

[0002]

2. Description of the Related Art Conventionally, a press machine which draws a pair of dies by approaching and separating from each other has been widely used. For example, FIGS. 2 and 3 show an example of a single-action type press machine, in which wrinkle holding is performed by a wrinkle holding ring 30 and drawing is performed by a die 18 and a punch 12. A wrinkle holding load is applied based on Pa. FIGS. 15 to 17 show an example of a double-action type press machine, which performs wrinkle holding by a wrinkle holding ring 156 attached to an outer slide 160 and a punch type 162 and a bolster 154 attached to an inner slide 164. The drawing process is performed with the die 152 provided, and a wrinkle holding load is applied based on the air pressure Pe of the cylinder 184. In such a conventional press machine, the air pressures Pa and Pe and the relative distance ha (due to die height) are given by trial and error while performing trial hitting in advance so that an appropriate wrinkle holding load that does not cause cracks or wrinkles is applied. Adjustment) is usually adjusted. That is, the wrinkle holding load for performing appropriate press working is different for each mold, and the weight of the wrinkle holding rings 30 and 156 constituting the mold is different for each mold. Since the pressure receiving area, sliding resistance, rigidity, and the like of the air cylinder 42 and the cylinder 184 are different for each press machine, it is desirable that the mold is mounted on the press machine that actually performs the drawing process without wrinkles or cracks while performing a test strike. Therefore, it was necessary to adjust the wrinkle pressing load, that is, the air pressure Pa and the like so that a press-formed product was obtained.

[0003] On the other hand, the weight of the mold and the wrinkle holding load for performing appropriate drawing are determined in advance for each mold, and the sliding resistance, the pressure receiving area of the air cylinder, and the like.
Rigidity and the like are obtained in advance for each press machine, and based on such information, the air pressures Pa and Pe and the relative distance ha at which the drawing is performed with the wrinkle pressing load are automatically set. Press machines are being considered. According to such a press machine, troublesome adjustment work due to trial and error is eliminated, and the burden on the operator is greatly reduced, and a press molded product of excellent quality can be stably obtained.

[0004]

However, according to experiments by the present inventors, even in such a press machine, if press working is continuously performed, defects such as cracks may occur in the press-formed product. There was a problem that it became easier.
This is because heat is generated by the passage resistance when the press material passes between the pair of molds, and the temperature of the mold rises as the number of presses increases, so that the temperature rises to the press material and the adherence to the press material occurs. The lubricating characteristics of the lubricating oil and the friction characteristics of the mold and press material change, and the lubricating oil is more likely to evaporate, increasing the passage resistance. It is considered that defects such as cracks easily occur in the molded product. Another problem is that wear of the mold is promoted due to the increase of the passage resistance, and the life is shortened.

Considering the relationship between the passing resistance and the calorific value, first, the calorific value Qo in the grinding process is as follows: the tangential grinding resistance is Ft, the grinding time is τ, and the peripheral speed of the grinding wheel is V.
a, when the moving speed of the workpiece is Vb, it is expressed by the following equation (1). Applying this to the case of drawing,
The passage resistance determined by the surface roughness of the mold and the press material and the lubrication conditions is μ, the resistance of the bend return of the press material by the bead at the wrinkle holding portion is r, and the surface pressure of the wrinkle holding is f
Assuming that (t), the tangential passage resistance is (μ + r) · f (t)
, The inflow of press material in the tangential direction is W,
Assuming that the width of the press material is w, the calorific value Qs at the wrinkle holding portion can be expressed by the following equation (2). Further, since the inflow amount W is represented by the following equation (3), the heat generation amount Qs is eventually represented by the following equation (4). Then, the heat generation amount Qs is generated for each press working, and the mold temperature gradually increases until the heat generation and the heat radiation are balanced. In addition,
A in the equation (3) is a predetermined constant.

[0006]

Qo = Ft · (Va ± Vb) · τ (1) Qs = (μ + r) · f (t) · W · w (2) W = a (μ + r) · ∫f (T) dt (3) Qs = (μ + r) ² · f (t) · ｔf (t) dt · w (4)

On the other hand, the tension Te when the press material is drawn in during the drawing process is expressed by the following equation (5).
Increases, the tension Te increases even if the wrinkle pressing surface pressure f (t) is the same, and the press-formed product is liable to crack. Note that, as is apparent from the above equation (4), as the passing resistance μ increases, the calorific value Qs also increases,
A vicious cycle occurs in which the mold temperature further increases and the passage resistance μ further increases.

[0008]

[Expression 2] Te = (μ + r) · f (t) (5)

The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent a press-formed product from having problems such as cracks even if the number of presses is increased.

[0010]

The first object of the present invention can be achieved by reducing the wrinkle holding load according to the number of presses. The first invention is shown in FIG. As shown in, in a press machine that performs drawing while performing wrinkle press, a device that automatically changes the wrinkle press load when performing the wrinkle press,
(A) a wrinkle holding load adjusting means for adjusting the wrinkle holding load; (b) a press number detecting means for counting the number of presses performed continuously by the press machine; (c) the number of presses A wrinkle holding load control means for controlling the wrinkle holding load adjusting means such that the wrinkle holding load decreases as the number of presses counted by the detection means increases.

[0011]

In such a wrinkle holding load automatic changing device, the number of presses is counted by the number-of-presses detecting means, and the passing resistance μ increases as the number of presses increases, in other words, the temperature of the mold rises. Accordingly, the wrinkle holding load adjusting means is controlled by the wrinkle holding load control means so as to reduce the wrinkle holding load, so that an appropriate tension Te can be obtained irrespective of the increase in the passage resistance μ. That is, as is apparent from the above equation (5),
Since the tension Te generated in the press material at the time of drawing is proportional to the wrinkle pressing surface pressure f (t), if the wrinkle pressing load is reduced in accordance with the increase of the passage resistance μ due to the temperature rise, the tension Te increases. Thus, cracking of the press-formed product and early wear of the mold are prevented. Also, when the wrinkle holding load is reduced in this way,
As is apparent from the above equation (4), the calorific value Qs at the time of press working is reduced, so that the temperature rise and the increase of the passage resistance μ are suppressed, and the mold temperature which balances with the heat radiation amount is reduced. The effects of heat are reduced.

[0012]

As described above, according to the first invention, the wrinkle pressing load is reduced in accordance with the number of times of pressing. The increase in the tension Te of the press material is suppressed, cracks in the press-formed product and early wear of the mold are prevented, and the calorific value Qs is reduced, so that the mold temperature in proportion to the amount of heat radiation is lowered, and in general press working, The effects of heat are reduced.

[0013]

In order to achieve the above-mentioned object, a second aspect of the present invention is to provide a method according to claim 2 shown in FIG.
As shown in the above, in a press machine that performs drawing while performing wrinkle holding, a device that automatically changes the wrinkle holding load when performing the wrinkle holding, (a) the wrinkle holding load is A wrinkle presser load adjusting means for adjusting;
(B) a press number detecting means for counting the number of presses in which press working is continuously performed by the press machine;
(C) timer means for measuring the stop time of the press machine; and (d) the wrinkle holding load decreases as the number of presses counted by the press number detecting means increases, and the stop measured by the time counting means. A wrinkle holding load control means for controlling the wrinkle holding load adjusting means such that the wrinkle holding load increases as the time is longer.

[0014]

According to the second aspect of the present invention, the number of presses is counted by the number-of-presses detecting means, and the stop time of the press machine is measured by the time measuring means. In order to increase the wrinkle holding load, the wrinkle holding load adjusting means is controlled by the wrinkle holding load control means,
By reducing the wrinkle pressing load according to the number of presses, similarly to the first invention, the increase in the tension Te is suppressed regardless of the increase in the passage resistance μ, thereby preventing cracks and early wear of the mold. At the same time, the calorific value Qs decreases and the mold temperature that balances with the heat radiation amount decreases, so that the influence of heat is reduced in the entire press working. On the other hand, when the press machine is stopped by a break or the like with the wrinkle holding load reduced in this way, the temperature of the mold decreases due to heat radiation according to the stop time, and the passage resistance μ is changed due to a change in lubrication conditions and the like.
When the press working is restarted with the wrinkle holding load as it is, sufficient tension Te cannot be obtained, and wrinkles may be easily generated in the press-formed product. Although the tension Te may be too large, in the present invention, since the wrinkle pressing load is increased according to the stop time, an appropriate tension Te is obtained irrespective of a decrease in the passage resistance μ to prevent the occurrence of defective products. Is done.

[0015]

As described above, according to the second aspect of the present invention, since the wrinkle pressing load is reduced in accordance with the number of times of pressing, the press-formed product can be formed irrespective of the increase in the passage resistance μ due to the temperature rise of the mold. Cracks and early wear of the mold are prevented, and the calorific value Qs is reduced to lower the mold temperature in proportion to the heat radiation, thereby reducing the influence of heat in the entire press working.
Further, since the wrinkle pressing load is increased in accordance with the stop time, wrinkles are prevented from being generated in the press-formed product regardless of the decrease in the passage resistance μ due to the temperature drop of the mold.

[0016]

In order to achieve the above-mentioned object, a third aspect of the present invention is directed to a third embodiment of the invention shown in FIG.
As shown in the above, in a press machine that performs drawing while performing wrinkle holding, a device that automatically changes the wrinkle holding load when performing the wrinkle holding, (a) the wrinkle holding load is A wrinkle presser load adjusting means for adjusting;
(B) temperature detecting means for measuring the temperature of the wrinkle-holding portion where the wrinkle-holding is performed; and (c) the wrinkle-holding load decreases as the temperature of the wrinkle-holding portion measured by the temperature detecting means increases. And wrinkle holding load control means for controlling the wrinkle holding load adjusting means.

[0017]

The wrinkle holding load automatic changing device measures the temperature of the wrinkle holding portion by the temperature detecting means, and reduces the wrinkle holding load by the wrinkle holding load control means so that the higher the temperature is, the less the wrinkle holding load is. When the mold temperature is high and the passage resistance μ is large, the wrinkle holding load is reduced. On the other hand, when the mold temperature is low and the passage resistance μ is small, the wrinkle holding load is increased. For this reason, an appropriate tension Te can always be obtained irrespective of the variation of the passage resistance μ due to the temperature change of the mold, wrinkles and cracks can be prevented from being generated, and the excessive tension Te can be caused. Premature wear of the mold is suppressed. In addition, since the calorific value Qs is reduced by reducing the wrinkle holding load in accordance with the temperature rise, the mold temperature in proportion to the heat release amount is reduced, and the influence of heat is reduced in the entire press working.

[0018]

As described above, according to the third aspect of the present invention, the wrinkle holding load is controlled in accordance with the temperature of the wrinkle holding portion. The generation of cracks and the like and the early wear of the mold are prevented, and the calorific value Qs is reduced to lower the mold temperature in proportion to the heat radiation amount, thereby reducing the influence of heat in the entire press working.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 2 shows an example of a single-action press machine 10 for performing drawing. A bolster 14 to which a punch mold 12 is attached is fixedly disposed on a base (not shown) via a bed 16 while a die The slide plate 20 to which the mold 18 is attached is moved up and down by four plungers 22. The bolster 14 is provided with a large number of through holes 26 for disposing the cushion pins 24, and a cushion pad 28 for supporting the cushion pins 24 is disposed below the bolster 14. . The cushion pins 24 support the wrinkle holding ring 30 provided together with the punch mold 12, and are provided in an arbitrary number at predetermined positions predetermined according to the shape of the wrinkle holding ring 30. You. The punch 12, the wrinkle holding ring 30, and the die 18 correspond to a pair of dies which are detachably attached to the press machine 10 and are used. The drawing process is performed by the punch die 12 and the die die 18 while wrinkling the portion.

The cushion pad 28 has a number of hydraulic cylinders 32 corresponding to the through holes 26,
The lower ends of the cushion pins 24 are each brought into contact with the piston of the hydraulic cylinder 32.
The pressure chambers of the hydraulic cylinders 32 are communicated with each other, and when hydraulic oil is supplied from the electric pump 34 and the electromagnetic on-off valve 36 is controlled to open and close,
The hydraulic pressure Ps in the pressure chamber is adjusted. The oil pressure Ps is detected by the oil pressure sensor 38 and is applied to the plurality of cushion pins 24 by the wrinkle pressing load F.
s is adjusted so as to act almost equally.

The cushion pad 28 can move up and down while being guided by a guide 40, and is constantly urged upward by an air cylinder 42. The pressure chamber of the air cylinder 42 is communicated with an air tank 44, and the air tank 44 is connected to a pressure air source 48 in the factory via an electromagnetic ON / OFF supply / exhaust valve 46.
The air pressure Pa in the pressure chamber or in the air tank 44 is adjusted by switching control of the FF supply / exhaust valve 46. The air pressure Pa is detected by the air pressure sensor 50 and is adjusted according to the wrinkle holding load Fs.

On the other hand, the plunger 22 is connected to the slide plate 20 via a die height adjusting mechanism 52 as shown in FIG. The die height adjusting mechanism 52 is provided on a screw shaft 54 provided integrally with the plunger 22, and a nut member 56 screwed to the screw shaft 54 and a worm wheel 58 fixed to the nut member 56. And a servo motor 60 that rotationally drives the worm screwed to the worm wheel 58. Then, the worm wheel 58 and the nut member 56 are rotationally driven in both forward and reverse directions by the servo motor 60, so that the height position of the die height adjusting mechanism 52 with respect to the screw shaft 54, that is, the relative distance h between the plunger 22 and the slide plate 20 Is changed. This relative distance h is detected by a rotary encoder 59 (see FIG. 4) provided on the servomotor 60. As the relative distance h increases, the slide plate 20 is lowered with respect to the plunger 22, and the pressing force when the plunger 22 reaches the lower end is changed. It is adjusted according to the press load Fp. The four plungers 22 are respectively connected to the slide plate 20 via the die height adjusting mechanism 52.
And the relative distance h is adjusted.
Further, a strain gauge 61 is attached to each plunger 22 to detect each load Foi (i = 1, 2, 3, 4) acting on each plunger 22.

The die height adjusting mechanism 52 includes a piston 6 of a hydraulic cylinder 62 provided to prevent overload.
4, while the housing of the hydraulic cylinder 62 is integrally provided on the slide plate 20. The pressure chamber of the hydraulic cylinder 62 is filled with hydraulic oil, and the pressure chamber communicates with an oil chamber 68 of the cylinder 66. Air chamber 70 of cylinder 66
Is connected to an air tank 72, and the air tank 72 is an electromagnetic ON / OFF supply / exhaust valve 7.
4 and connected to the pressure air source 48,
By controlling the switching of the N, OFF supply / exhaust valve 74, the air pressure Pc in the air chamber 70 and the air tank 72 is adjusted. The air pressure Pc is detected by the air pressure sensor 76. When an excessive load acts on the hydraulic cylinder 62, the air pressure Pc causes the piston to retreat toward the air chamber 70 and the die height adjusting mechanism 52
The pressure is adjusted according to the press capability of the press machine 10 so as to allow the press machine 10 and the slide plate 20 to approach each other, and to prevent damage to the press machine 10 and the mold. The hydraulic cylinder 62, the cylinder 66, the air tank 72, and the like are provided at connection portions between the four plungers 22 and the slide plate 20, respectively.
Is regulated.

The slide plate 20 is connected to four balancer air cylinders 80 disposed on a machine frame 78 (see FIG. 2) of the press machine 10. The pressure chamber of the air cylinder 80 is communicated with an air tank 82, and the air tank 82 is an electromagnetic ON / O
It is connected to the pressure air source 48 via the FF supply / exhaust valve 84, and the ON / OFF supply / exhaust valve 84 is switched so that the air pressure Pb in the pressure chamber or in the air tank 82 is adjusted. Has become. This air pressure P
The pressure b is detected by the air pressure sensor 86, and the pressure is adjusted to balance the weight of the slide plate 20 and the die 18. The pressure chambers of the four air cylinders 80 are connected to a common air tank 82.

The press machine 10 includes a controller 90 as shown in FIG. 4, and outputs from the air pressure sensors 50, 86, 76, the oil pressure sensor 38, the rotary encoder 59, and the strain gauge 61. Air pressure P
Signals representing a, Pb, Pc, oil pressure Ps, relative distance h, and load Foi are supplied to the controller 90, respectively. The controller 90 is constituted by a microcomputer having a CPU, a RAM, a ROM, an input / output interface circuit, an A / D converter, etc., and performs signal processing in accordance with a program stored in the ROM in advance while utilizing a temporary storage function of the RAM. And outputs drive signals for switching the ON / OFF supply / exhaust valves 46, 84, 74 and the opening / closing valve 36, and changing the operating states of the pump 34 and the motor 60. In the figure, motor 60, strain gauge 61, O
Although only one N, OFF supply / exhaust valve 74 and one air pressure sensor 76 are shown, the same processing is performed for each of the number provided in the press machine 10, in this embodiment, four each. Such a controller 90 also includes
A setting device 92 such as a keyboard, a personal computer, etc., and a transceiver 94 are connected. Machine information specific to the press machine 10 is input from the setting device 92 in advance. Is entered. That is, the punch mold 12 stores mold information unique to the mold and an ID card 96 having a transmission function and a battery.
(See FIG. 2) is attached, and by receiving the data capture signal transmitted from the transceiver 94,
The mold information is transmitted from the D card 96, and the mold information is taken into the controller 90 via the transceiver 94.

The machine information and the mold information are based on the air pressures Pa, Pb,
Information required to determine the hydraulic pressure Ps and the relative distance h,
For example, it is as follows. The mold information includes
Information such as the type of the mold, that is, the vehicle type and product number, the press machine used, the process, and the like are also included. (Machine information)-Weight Wa of cushion pad 28-Weight Wp of cushion pin 24-Weight Ws of slide plate 20-Pressure receiving area Aa of air cylinder 42-Pressure receiving area (total of four) Ab of air cylinder 80-Hydraulic cylinder 32 The pressure receiving area As of 32 ・ The bulk modulus K of the hydraulic oil supplied to the hydraulic cylinder 32 ・ The average run-in dimension Xav of the piston of the hydraulic cylinder 32 ・ The oil amount V ・ h-Fpi provisional characteristics (Fpi = a ・ h) (gold (Type information)-Weight Wr of wrinkle retainer ring 30-Weight Wu of upper die (die type 18)-Number of cushion pins 24 used-Press load Fpoi-Wrinkle retainer load Fso-Number of press times-Subtraction value α-Stop time Characteristic

Here, the weight Wa of the cushion pad 28
Is the value obtained by subtracting the sliding resistance. For example, by measuring the load on the slide plate 20 while changing the air pressure Pa using the load measuring device 100 shown in FIG. It can be obtained from the characteristics. The load measuring device 100 includes a pair of load measuring tables 102 and 104.
Four pillars 106 and 108 are erected on the 104, respectively, and strain gauges 110 and 112 are attached to the pillars 106 and 108, respectively.
The load measuring table 102 is provided with a large number of through-holes 114 corresponding to the through-holes 26 formed in the bolster 14. I can do it. The load measuring table 104 is provided with the through holes 114 and 26.
Are supported on a plurality of cushion pins 24 arranged. And the strain gauge 11
Numerals 0 and 112 are connected to a dynamic strain meter 116, and a load waveform is recorded by an electromagnetic oscilloscope 118. The dynamic strain meter 116 has an amplification function, a zero point adjustment function, and the like.
The electromagnetic oscilloscope 118 records a change in load caused by the lowering and raising of the slide plate 20 with high followability. The strain gauges 110 and 112 are connected to one support 10.
6 and 108 respectively, and are connected so as to form a bridge circuit.

When measuring the load of the single-action press machine 10, when the slide plate 20 is lowered by the plunger 22 and comes into contact with the column 108 of the load measuring table 104 supported on the cushion pin 24, the load is measured. The measuring table 104 is lowered against the urging force of the air cylinder 42 and the load at that time is 4
Detected by strain gauges 112 provided on the columns 108 of the book. When the slide plate 20 further descends and the load measuring table 104 comes into contact with the load measuring table 102, the load detected by the strain gauge 112 sharply increases in accordance with the rigidity of each part of the press machine 10. FIG.
Is a strain gauge 11 provided on any one support 108.
2 illustrates an example of a load change detected by
The load Fsi corresponds to a wrinkle holding load, and the load Fpi corresponds to a press load. FIG. 9 is a graph in which the wrinkle pressing load Fsi is measured while changing the air pressure Pa of the air cylinder 42, and the weight Wa of the cushion pad 28 is obtained based on the load Fxi obtained from this graph. That is, four measurement values Fxi (i = 1, 2, 3,
The weight Wa is obtained by subtracting the weight of the load measuring table 104 and the cushion pin 24 from the total load Fx of 4). The weight Wa can also be obtained from a graph of the total load Fs of the wrinkle holding load Fsi and the air pressure Pa. The weight Wa is obtained by subtracting the sliding resistance and the like of the air cylinder 42 from the actual weight of the cushion pad 28. Also, the press machine 10 including the air leakage of the air cylinder 42 and the detection error of the air pressure sensor 50 is included. It is a unique value. It should be noted that the actual weight of the cushion pad 28 and the sliding resistance may be divided into machine information.

The weight Wp of the cushion pin 24 is an average value of a large number of cushion pins 24 used in the press machine 10, and the weight Ws of the slide plate 20 is different from a weight of a guide member (not shown) for guiding the slide plate 20. It is the value obtained by subtracting the sliding resistance between them. In particular,
By operating the press machine 10 to detect the load Foi when the slide plate 20 is lowered by the strain gauge 61 and changing the air pressure Pb of the air cylinder 80, the total load Fo of the four strain gauges 61 is changed.
-Find the air pressure Pb characteristic and calculate its total load Fo-air pressure P
From the characteristic b, the weight Ws can be obtained in the same manner as in the case of the cushion pad 28. The sliding resistance can be separately set as machine information. The pressure receiving area Aa of the air cylinder 42 takes into account the air leakage of the air cylinder 42. For example, the slope of the graph of the total load Fs of the wrinkle holding load Fsi and the air pressure Pa corresponds to the pressure receiving area Aa. When a plurality of air cylinders 42 are provided, the total area is set as the pressure receiving area Aa. The pressure receiving area Ab of the air cylinder 80 is the sum of the four air cylinders 80, and is obtained from the total load Fo-air pressure Pb characteristic similarly to the pressure receiving area Aa. The pressure receiving area As of the hydraulic cylinder 32 is an average value of a number of hydraulic cylinders 32. For example, the wrinkle holding load Fsi and the air pressure P in FIG.
When obtaining the characteristic of “a”, the hydraulic pressure Ps is detected by the hydraulic pressure sensor 38 and can be obtained from the characteristic of the total wrinkle pressing load Fs−the hydraulic pressure Ps.

The bulk modulus K is determined according to the hydraulic oil used, and the average driving dimension Xav is used to evenly contact the plurality of cushion pins 24 with the wrinkle holding member such as the wrinkle holding ring 30. The downward stroke of the piston of the hydraulic cylinder 32, regardless of variations in the length of the cushion pin 24, inclination of the cushion pad 28, etc., the piston of the hydraulic cylinder 32 is driven downward by all the cushion pins 24, In order to prevent the piston of the hydraulic cylinder 32 from reaching the stroke end irrespective of the shock acting on the cushion pin 24 when the slide plate 20 is lowered, it is necessary to experimentally determine whether the piston pin of the hydraulic cylinder 32 has reached the stroke end or to determine the variation in the length of the cushion pin 24 or the hydraulic cylinder. It is determined based on the maximum stroke of the 32 pistons and the like. The oil amount V is the total capacity of the hydraulic oil present on the hydraulic cylinder 32 side with respect to the check valve 39 (see FIG. 2) when the piston of each hydraulic cylinder 32 is positioned at the rising end.

H-Fpi provisional characteristics (i = 1, 2, 3, 4)
Is the press load F when the plunger 22 reaches the lower end.
The characteristic (Fpi = a · h) between pi and the relative distance h is different depending on the rigidity of the die used. Therefore, the relative distance is obtained by interposing a member having higher rigidity than the normal die. h
Are variously changed, and the press load Fpi when the plunger 22 reaches the lower end is measured by the strain gauge 61, and reflects the rigidity of the press machine 10. This h-F
The measurement of the pi temporary characteristic is performed by adjusting the air pressure Pb such that the slide plate 20 is lowered by the plunger 22 in a state where the lift force of the slide plate 20 and the air cylinder 80 are balanced. The one-dot chain line in FIG. 10 illustrates an example of such h-Fpi provisional characteristics, and is determined based on the maximum value h ₀ of the relative distance h when the press load Fpi is zero. This h-
The temporary Fpi characteristics are determined for each of the four die height adjustment mechanisms 52, and the total press load Fp is the sum of the respective press loads Fpi. The h-Fpi provisional characteristic can be obtained from the load Fpi in FIG. 8 using the load measuring device 100.

The wrinkle holding ring 30 in the mold information
The weight Wr of the die die 18 and the weight Wu of the die die 18 are actually measured values after manufacturing the wrinkle holding ring 30 and the die die 18, and the number n of the cushion pins 24 used is the shape of the wrinkle holding ring 30 Is determined so as to obtain an appropriate press-formed product. Press load Fpoi (i =
1, 2, 3, 4) are wrinkle holding ring 30, die type 1
8, and the punch die 12 is attached to a test tri-press for actual press working, and the load conditions for obtaining an appropriate press-formed product are determined by trial and error. This excludes the influence of the sliding resistance of each part and the like. For example, when a tri-press configured similarly to the press machine 10 of FIGS. 2 and 3 is used, the slide plate 20 and the die mold 18 are used.
The air pressure Pb is adjusted such that the slide plate 20 is lowered by the plunger 22 in a state where the lifting force of the air cylinder 80 is balanced with the load, and the load Foi detected by the strain gauge 61 when performing the press working in that state. It is determined based on. This press load Fpoi is 4
At each point of the press load, the total press load is the sum of their press loads Fpoi.

The wrinkle pressing load Fso—the number of times of pressing, like the press load Fpoi, is not affected by the weight of the mold and the sliding resistance of each part of the tripress.
The wrinkle holding load Fso for obtaining an appropriate press-formed product without wrinkles or cracks was obtained in relation to the number of presses. This is because, when press working is performed continuously, heat is generated by the passage resistance μ when the press material passes between the pair of dies 18 and 30, and the temperature of the wrinkle holding portion increases as the number of presses increases. Due to this temperature rise, the lubricating characteristics of the lubricating oil and the friction characteristics of the mold and press material attached to the press material change due to this temperature rise, and the lubricating oil is easily volatilized, increasing the passage resistance μ, This takes into account the fact that the tension Te when the press material is drawn in during drawing is increased. By continuously performing press work on the press material under the same lubricating conditions as in the case of mass production, the temperature change and cracking can be prevented. It is required based on the situation of occurrence.
Table 1 is an example, and the load number N is increased by 1 each time the number of presses exceeds a predetermined constant number Co of, for example, about 100, and the wrinkle holding load Fso is determined for each load number N. . As is clear from Table 1, the wrinkle holding load Fso is reduced as the load number N is larger and the number of presses is larger. This wrinkle holding load Fso
Is the total load, which is determined based on the total load Fo of the loads Foi detected by the strain gauge 61.

[0034]

[Table 1]

Further, the subtraction value α-stop time characteristic defines the subtraction value α of the load number N so as to increase the wrinkle pressing load Fso according to the stop time of the press machine. This is because, when the press working is performed continuously as described above, the temperature of the molds 18 and 30 rises to a temperature where the calorific value Qs due to the passage resistance μ and the heat radiation amount are balanced. When the operation is interrupted, the temperature of the mold is reduced by heat radiation according to the stop time, and the passage resistance μ is reduced due to a change in lubrication conditions. That is, when the press working is resumed with the wrinkle holding load as it is, the tension Te decreases in accordance with the decrease in the passage resistance μ, so that wrinkles are easily generated in the press-formed product, while the wrinkle holding load at the beginning of the press working is increased. Specifically, under the load condition in the case where the load number N = 1 in Table 1 described above, the tension Te may become too large to cause a crack, and therefore, the load number at which appropriate press working is performed according to the stop time. The subtraction value α of N is obtained in advance by an experiment or the like. FIG. 11 shows an example of such a subtraction value α-stop time characteristic, where Nmax at the maximum value (Nmax−1) of the subtraction value α is the maximum value of the load number N, that is, the heat generation amount Qs.
Wrinkle holding load F when the amount of heat dissipation is approximately balanced
so is the set load number. In addition, although it depends on the material of the mold, in general, when the stop time exceeds 1 hour, the temperature of the mold decreases to approximately room temperature.
The subtraction value α is the largest (Nmax −1).

Returning to FIG. 4, a limit switch 124 and a start switch 126 are also connected to the controller 90. The limit switch 124 is turned on when the plunger 22 of the press machine 10 reaches the lower end.
A press signal SP is output to the controller 90 each time press processing is performed once. The start switch 126 is turned on and off by an operator when starting and stopping the press working, and outputs a start signal SS indicating the ON state to the controller 90.

The controller 90 executes the functions shown in FIG. 5 by performing signal processing according to a program predetermined in the ROM. In FIG. 5, the machine information memory 130 includes:
The machine information previously stored by the setting device 92 is stored. The mold information memory 132 stores the mold information read from the ID card 96 by the transceiver 94 after the mold is mounted on the press machine 10. Is stored. Further, based on the machine information stored in the machine information memory 130 and the mold information stored in the mold information memory 132, the air pressure Pax calculation block 134 is used to set the mold information in Table 1 described above. An air pressure Pax for generating a wrinkle holding load Fso (100 tf in this embodiment) having a load number N = 1 in the wrinkle holding load Fso-press number characteristic is calculated according to the following equation (6). Air pressure Pa
The adjustment block 136 controls the ON / OFF supply / exhaust valve 46 so that the air pressure Pa in the air tank 44 detected by the air pressure sensor 50 becomes the calculated air pressure Pax. Thus, wrinkle holding is performed with the wrinkle holding load Fso at the load number N = 1 set as the mold information. The capacity of the air tank 44 is sufficiently large, and the change in the air pressure Pa caused by the change in the volume of the air cylinder 42 due to the lowering of the cushion pad 28 is almost negligible. It can also be calculated. Air pressure Pax calculation block 134
Is the wrinkle holding load F at the initial setting of the air pressure Pa.
The air pressure Pax is calculated in advance by reading the wrinkle holding load Fso of the load number N = 1 from the so-press frequency characteristic.

[0038]

Pax = (Fso + Wa + Wr + n · Wp) / Aa (6)

The hydraulic pressure P ₀ , P ₁ calculation block 138 is based on the machine information stored in the machine information memory 130 and the mold information stored in the mold information memory 132.
An initial hydraulic pressure for causing the wrinkle holding load Fso to act on the wrinkle holding ring 30 approximately uniformly through the cushion pins 24;
That is, the hydraulic pressure P ₀ in a state where the die 18 is not in contact with the wrinkle holding ring 30 is calculated from the relationship of the following equation (7), and each cushion pin is pressed at the time of press working in which the wrinkle holding ring 30 is pressed by the die 18. 24
Equally calculates the target hydraulic pressure P ₁ when the blank-holding force Fso is allowed to act on the relationship following equation (8). Then, the hydraulic pressure Ps adjusting block 140, first, the initial pressure of the pressure Ps detected by the hydraulic pressure sensor 38 so that the initial hydraulic pressure P _0, controls the pump 34 and the on-off valve 36. Thereby, at the time of press working in which the wrinkle holding ring 30 is pressed by the die 18, basically, the piston of each hydraulic cylinder 32 is pushed in by the average driving dimension Xav, and the wrinkle holding load Fso is increased via each cushion pin 24. Although almost be evenly act on pressure ring 30, the volume elastic coefficient K is such not necessarily constant by mixing such air, the initial oil pressure P ₀ is not necessarily accurate. For this reason, the hydraulic pressure Ps adjustment block 140
After adjusting s to the initial oil pressure P ₀ , the hydraulic pressure Ps at the time of press working is read when the test press is actually performed, and the initial oil pressure Ps is adjusted so that the oil pressure Ps substantially matches the target oil pressure P _1.
Correct ₀ . That is, when the hydraulic pressure Ps during pressing is higher than the target pressure P ₁ is not pressure ring 30 in a part of the cushion pin 24 abuts against the action biased is blank-holding force Fso to the rest of the cushion pins 24 for the case it is, cushion pins 2 by lowering the initial pressure P ₀
It is sufficient that the amount of run-in of 4 becomes large as a whole. Further, when the hydraulic pressure Ps during pressing is lower than the target hydraulic pressure P _1, when the piston portion of the hydraulic cylinder 32 is part of the blank-holding force Fso reached the stroke end is acting on the cushion pad 28 directly because it is, it may be increased initial pressure P ₀ so as not to reach up to the stroke end.

[0040]

Xav = (Fso−n · As · P ₀ ) V / n ² · As ² · K (7) Fso + Wr + n · Wp = n · As · P ₁ (8)

The air pressure Pbx calculation block 142 calculates the air pressure Pbx for lifting the slide plate 20 and the die 18 with a force that balances them with the following equation (9), based on the machine information and the mold information. The air pressure Pb adjustment block 144 controls the ON / OFF supply / exhaust valve 84 so that the air pressure Pb in the air tank 82 detected by the air pressure sensor 86 becomes the calculated air pressure Pbx.
Is switched. Thereby, the press working can be performed with each press load Fpoi set as the mold information without being affected by the weight of the slide plate 20 and the die 18. The capacity of the air tank 82 is sufficiently large, and the change in the air pressure Pb caused by the change in the volume of the four air cylinders 80 due to the lowering of the slide plate 20 is almost negligible. The pressure Pbx can also be calculated.

[0042]

Pbx = (Wu + Ws) / Ab (9)

The relative distance h adjusting block 146 controls the four die height adjusting mechanisms 52 based on the machine information and the mold information so that the press working is performed with each press load Fpoi set as the mold information. The relative distances h are independently adjusted. First, a reference value h ₀ , which is the maximum value of the relative distance h when the press load Fpi is 0, is determined based on the load Foi supplied from the strain gauge 61. determines the relative distance h ₁ of press load Fpoi is obtained from h-Fpi temporary characteristic in FIG. 10 which is set as the machine information is indicated by one-dot chain line (Fpi = a · h). Next, the relative distance h is adjusted to h ₁ by the servo motor 60 based on the reference value h ₀ , and the press load Fp ₁ based on a signal supplied from the strain gauge 61 when a test press is performed in that state. Is measured. The preset h-
Fpi temporary property, since rigidity than conventional mold is set with reference to the case high, generally pressing load Fp ₁ is smaller than the pressing load Fpoi. Subsequently, the relative distance h
Relative distance h smaller than ₁ by a predetermined change amount Δh
₂ and the press load Fp ₂ in the same manner.
Is measured. Based on the relative distances h ₁ and h ₂ and the press loads Fp ₁ and Fp ₂ , the h-Fpi characteristic (Fpi = b · h) shown by the solid line in FIG. From the h-Fpi characteristic, press load Fpoi
Is determined, and the servo motor 60 controls the relative distance h to be hx. The determination and adjustment of the relative distance hx are performed independently for the four die height adjustment mechanisms 52 in the same manner as described above. Thus, regardless of the difference in rigidity of each press machine 10, etc., each press load Fpo set as the mold information is obtained.
Pressing is performed favorably at i.

In addition to the above-described controls, the controller 90 also determines that the four loads Foi detected by the strain gauges 61 are equal to predetermined overload prevention loads Foli (i = 1, 2, 3, 4). )
The air pressure Pc is controlled. That is, when the overload prevention load Foli acts on the overload prevention hydraulic cylinder 62 due to the presence of foreign matter or the like, the cylinder 6
6 retreats toward the air chamber 70 and the hydraulic cylinder 6
2 is allowed to flow into the oil chamber 68 and the pressure receiving area of the hydraulic cylinder 62 and the pressure receiving area of the oil chamber 68 and the air chamber 70 of the cylinder 66 are adjusted so that the slide plate 20 and the plunger 22 can approach each other. Air pressure P based on area
cx is set, and the air pressure Pc is equal to the air pressure Pcx.
The switching control of the ON / OFF supply / exhaust valve 74 is performed so that The pressure control of the air pressure Pc is performed independently for each of the four cylinders 66. This prevents damage to the press machine 10, the mold, and the like due to an excessive press load. The air pressure Pc can be set irrespective of the die to be used. Therefore, the air pressure Pc may be adjusted in advance by manual operation or the like.

As described above, in the press machine 10 according to the present embodiment, the machine information unique to the press machine 10 and the transceiver 9 stored in the machine information memory 130 in advance.
4 based on mold information read from the ID card 96 via the ID card 96, regardless of the rigidity of each press machine, the sliding resistance of each part, etc. In order to reproduce the press conditions under which the pressing is performed, that is, the wrinkle pressing load Fso and the press load Fpoi, the air pressure Pax, Pbx, the initial oil pressure P ₀ , and the relative distance hx, which are the press working conditions, are respectively obtained. Since the air pressures Pa and Pb, the hydraulic pressure Ps, and the relative distance h are automatically initialized according to the values, troublesome setting work due to trial and error is eliminated, and the burden on the operator is greatly reduced. Press molded articles of excellent quality can be obtained stably.

The above air pressures Pa and Pb, oil pressure Ps,
And the relative distance h is not always exactly the air pressure Pax, Pb
It is not necessary to perform control so as to be equal to x, the initial hydraulic pressure P ₀ after correction, and the relative distance hx. .

On the other hand, the air pressures Pa and Pb and the hydraulic pressure P
After the s and the relative distance h are automatically initialized based on the mold information and the machine information, if the press machine 10 actually produces a large amount of press-formed products, The above air pressure Pa according to the stop time
Is changed. That is, the controller 90 includes a load number N change block 148, and calculates the number of presses and the stop time based on the press signal SP supplied from the limit switch 124 and the start signal SS supplied from the start switch 126, and In the pressure Pax calculation block 134, the wrinkle holding load Fso for calculating the air pressure Pax is changed.

FIG. 6 is a flowchart for explaining the specific function of the load number N changing block 148, which is repeatedly executed at a predetermined cycle time. Step S1
Then, it is determined whether or not the activation signal SS is ON. If not, the flag F is set to "0" in step S2.
When the start signal SS is turned on and the determination in step S1 is YE
When S is reached, it is determined in step S3 whether or not the flag F = 1. Since F = 0 at the beginning of the press working, step S4 is subsequently executed. This step S4
Then, a load number N is newly set based on the content of the timer TI, and the load number N is output to the air pressure Pax calculation block 134. Since the timer TI is sequentially reset in step S6 while the press machine 10 is operating, the timer TI at the time of execution of step S4
The content of I is determined by the activation switch 126 of the press machine 10.
Is calculated based on the subtraction value α-stop time characteristic shown in FIG. 11 from the content of the timer TI, and the current load number N is calculated from the current load number N. By subtracting the subtraction value α, a new load number N is calculated. Further, in the air pressure Pax calculation block 134 to which the new load number N is supplied, the wrinkle holding load Fso relating to the supplied load number N is read from the wrinkle holding load Fso-press number characteristic shown in Table 1, and the wrinkle holding force Fso is read. While the air pressure Pax is recalculated in accordance with the above equation (6) using the pressing load Fso, the air pressure Pa adjustment block 136 adjusts the air pressure Pa so as to become the newly calculated air pressure Pax. That is, the wrinkle pressing load Fs, in other words, the air pressure Pa is changed so that appropriate press working is performed in accordance with the stop time of the press machine 10, which is caused by a temperature drop of the mold due to heat radiation during stoppage. Thus, even if the lubrication conditions and the like change and the passage resistance μ decreases, an appropriate press-formed product without wrinkles or cracks is manufactured from the beginning of the press working.

Since the load number N is "1" at the minimum, when the subtraction value α is equal to or larger than the current load number N, "1" is set as a new load number N. . FIG. 11 shows the subtraction value α-stop time characteristic when the current load number N is Nmax, that is, when it is in a substantially steady state at the highest temperature. Therefore, the subtraction value α-stop time characteristic can be set for each current load number N.

In the following step S5, the flag F is set to "1", and in the subsequent cycle, step S6 is executed following step S3. In step S6, the timer TI
Is reset, and in the next step S7, the press signal S
It is determined whether P is ON. When the press signal SP is turned on, in other words, each time press processing is performed once, step S8 is executed, and 1 is added to the content C of the counter.
In step S9, it is determined whether or not the content C of the counter has reached the predetermined number Co, and when it reaches Co, step S10 is executed. In step S10, the load number N
Is determined to be the maximum value Nmax. If the load number N is the maximum value Nmax, the contents C of the counter are cleared in step S12, and the execution of steps S1 and subsequent steps is repeated. Step S11 is executed, and 1 is added to the current load number N to set a new load number N. Then, by outputting the new load number N to the air pressure Pax calculation block 134, the air pressure Pax calculation block 134 reads a new wrinkle holding load Fso from the wrinkle holding load Fso-press number characteristics shown in Table 1 and The air pressure Pax is calculated according to the above equation (6) according to the wrinkle holding load Fso, and the air pressure Pa adjustment block 136 changes the air pressure Pa so as to become the air pressure Pax. As a result, even if the temperature of the mold increases as the number of presses increases, and the passage resistance μ increases due to a change in lubrication characteristics, an appropriate press-formed product without cracks is manufactured. The constant number Co and the maximum value Nmax are set in accordance with the wrinkle holding load Fso-press number characteristics shown in Table 1.

As described above, the press machine 10 of this embodiment is
The wrinkle holding load Fso in Table 1 is reduced in accordance with the number of presses, and the wrinkle holding load Fs is reduced in accordance with the number of presses characteristic, the air pressure Pa is correspondingly reduced, and the subtraction value α− in FIG. The wrinkle holding load Fs is increased according to the stop time characteristic, and the air pressure P
Since a is raised, an appropriate press-formed product free of wrinkles and cracks is always produced regardless of the variation of the passage resistance μ due to the temperature change of the mold. Further, since the wrinkle pressing load Fs, that is, the air pressure Pa, is reduced in accordance with the number of presses, early wear of the mold due to the excessive tension Te is prevented, and the calorific value Qs is reduced to reduce the heat radiation amount. Since the mold temperature to be balanced is low, the influence of heat on the entire press working is reduced.

This embodiment is an embodiment of the first invention and the second invention, and includes a load number N change block 148.
The air pressure Pax calculation block 134 corresponds to wrinkle holding load control means, and the air pressure Pa adjustment block 136, the ON / OFF supply / exhaust valve 46, and the air pressure sensor 50 correspond to wrinkle holding load adjustment means. Also, the load number N
The part of the change block 148 for executing steps S7 and S8 and the limit switch 124 constitute the number-of-presses detecting means, the timer TI reset in step S6, and the execution of step S6 when the press machine 10 is stopped. S1 and S2 for preventing
Corresponds to the timing means.

Next, another embodiment will be described. In the following embodiments, portions common to the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 12 shows an arrangement in which a radiation thermometer 350 for non-contact temperature measurement based on radiant energy due to heat radiation is provided on the machine frame 78 of the press machine 10 via a mount 352 as temperature detection means. The temperature θ of the press-formed product 354 drawn by the press machine 10 is measured. The radiation thermometer 350 irradiates visible light to the temperature measurement unit so that an operator can visually check the temperature measurement unit, and the mount 352 can freely change the orientation of the radiation thermometer 350. In order to measure the temperature θ of the wrinkled portion of the press-formed product 354, that is, the portion where the sheet thickness is increased by drawing and the temperature where the temperature is most likely to rise due to the passage resistance μ can be measured. The direction of the radiation thermometer 350 is determined in advance according to the shape of the product 354 and the like.
Depending on the shape of the press-formed product 354, the radiation thermometer 350 may be provided at a plurality of locations,
It is also possible to increase the detection accuracy by measuring the temperatures θ of a plurality of portions.

In this embodiment, "wrinkle holding load Fso-temperature θ characteristic" is stored in the ID card 96 as the mold information. The wrinkle holding load Fso-temperature θ characteristic is obtained by continuously performing the press working without being affected by the weight of the mold and the sliding resistance of each part of the tripress, and the temperature θ of the wrinkle holding portion of the press-formed product. And the wrinkle holding load Fso is measured to obtain a proper press-formed product without wrinkles and cracks.
And the temperature θ. This is because when the press working is performed continuously, the press material is
Heat is generated by the passage resistance μ when passing between the positions 8 and 30, and as the number of presses increases, the temperature of the wrinkle holding portion rises. Considering that the lubrication characteristics and the friction characteristics of the mold and the press material change and the lubricating oil is easily volatilized, the passage resistance μ increases, and the tension Te when the press material is drawn in during drawing increases. The wrinkle holding load Fso-temperature .theta. Characteristic is obtained under the same lubricating conditions as in the case of mass production. FIG. 13 shows an example of such a wrinkle holding load Fso-temperature θ characteristic. The higher the temperature θ, the smaller the wrinkle holding load Fso. In this embodiment, the "wrinkle holding load Fso-press number characteristic" and the "subtraction value α-stop time characteristic" are unnecessary.

On the other hand, the controller 90 of the press machine 10
Is the load number N, as shown in FIG.
A wrinkle holding load Fso setting block 356 is provided instead of the change block 148. The wrinkle holding load Fso setting block 356 is supplied with the information on the temperature θ from the radiation thermometer 350 and the mold information memory 132 with the information on the wrinkle holding load Fso-temperature θ characteristic of FIG. And its wrinkle holding load Fso-
The wrinkle holding load Fso is set based on the temperature θ characteristic and the actual temperature θ, and the wrinkle holding load Fso is sequentially updated with the change of the temperature θ. The set wrinkle holding load Fso is
The air pressure Pax calculation block 358 determines the wrinkle holding load Fso based on the set wrinkle holding load Fso so that appropriate press working without cracks and wrinkles can be performed under the condition of the temperature θ at that time. The air pressure Pax is calculated according to the equation (1), and information on the air pressure Pax is output to the air pressure Pa adjustment block 136.

Therefore, when the temperature θ is high and the passage resistance μ is large, the wrinkle holding load Fso is reduced, and the air pressure Pa is correspondingly reduced. On the other hand, when the temperature θ is low and the passage resistance μ is small, the wrinkle holding load Fso is reduced. The load Fso is increased, and the air pressure Pa is correspondingly increased. For this reason, irrespective of the fluctuation of the passage resistance μ caused by the change of the temperature θ, an appropriate tension Te can always be obtained, wrinkles and cracks are prevented from being generated, and the excessive tension T
Premature wear of the mold due to e is suppressed. Further, the amount of heat Qs is reduced by reducing the wrinkle holding load Fs in accordance with the rise of the temperature θ, so that the temperature θ at the time of balance with the amount of heat radiation is reduced, and the influence of heat is reduced in the entire press working. .

This embodiment is an embodiment of the third invention. The wrinkle holding load Fso setting block 356 and the air pressure Pax calculation block 358 correspond to the wrinkle holding load control means, and the air pressure Pa adjustment block 136 and ON, OF
The F supply / exhaust valve 46 and the air pressure sensor 50 correspond to wrinkle holding load adjusting means.

FIG. 15 shows an example in which the present invention is applied to a double-action type press machine 150 for performing drawing. A die 152 is fixedly used on a bolster 154 and used. Reference numeral 156 is fixed to the outer slide 160 via the blank holder plate 158, and the punch die 162 is fixed to the inner slide 164 for use. The outer slide 160 can be moved up and down via four outer plungers 166, and the inner slide 164 can be moved up and down via four inner plungers 168. Wrinkle retainer ring 1 as shown
The pressing process is performed by the punch die 162 and the die 152 while pressing the peripheral edge of the press material 171 between the die 56 and the wrinkle holding portion 170 of the die 152. The die 152, the wrinkle holding ring 156, and the punch 162 correspond to a pair of dies which are detachably attached to the press machine 150 and used.

As is apparent from FIG. 16, the outer plunger 166 is provided with the die height adjusting mechanism 5 of the above embodiment.
2 is connected to the outer slide 160 via a die height adjustment mechanism 172 similar to that of FIG. This relative distance ha is detected by a rotary encoder 176 (see FIG. 18) provided on the servomotor 174. As the relative distance ha increases, the outer slide 160 is lowered with respect to the outer plunger 166, and the wrinkle pressing load Fs when the outer plunger 166 reaches the lower end is changed. It is adjusted according to the load Fs. The four outer plungers 166 are connected to the outer slide 160 via the die height adjusting mechanism 172, respectively, and the relative distance ha is adjusted. A strain gauge 178 is attached to each outer plunger 166 so as to detect each load Fai (i = 1, 2, 3, 4) acting on each outer plunger 166.

The die height adjusting mechanism 172 is integrally connected to a piston 182 of a hydraulic cylinder 180 provided for adjusting a wrinkle holding load, while a housing of the hydraulic cylinder 180 is integrally provided on an outer slide 160. Have been. The pressure chamber of the hydraulic cylinder 180 is filled with hydraulic oil, and the pressure chamber communicates with an oil chamber 186 of the cylinder 184. Cylinder 1
The air chamber 188 is communicated with an air tank 190, and the air tank 190 is connected to a machine frame 196 of the press machine 150 through a pair of pipes 192 and 194.
Are connected to the connecting tools 198 and 200 arranged in the first position.
These connectors 198 and 200 respectively include the connector 20 of the control box 202 shown in FIG.
Pressure-resistant connecting hose 20 having one end connected to 4a, 206a
8a and 210a are connected to each other. The air pressure Pe in the air tank 190 is detected by an air pressure sensor 212a disposed in the control box 202, and the air pressure is detected by an electromagnetic ON / OFF supply / exhaust valve 214a. The pressure Pe is regulated. Hydraulic cylinder 18
0, the cylinder 184, the air tank 190, etc. are provided at the connecting portions between the four outer plungers 166 and the outer slide 160, respectively. 190 is also connected to a connector provided on the machine casing 196 through a pair of pipes, and connected to the connector 204b of the control box 202 via pressure-resistant connecting hoses 208b to 208d and 210b to 210d. ~ 204
d, 206b to 206d, and the air pressure sensor 21
The air pressure P in the air tank 190 is determined by 2b to 212d.
e is detected respectively, and electromagnetic ON, OF
The air pressure Pe is regulated by the F supply / exhaust valves 214b to 214d, respectively. The air pressure Pe is adjusted according to the wrinkle holding load Fs. In addition, the connection tool 198,200,204a-204d, 20
6a-206d and pressure-resistant connecting hoses 208a-208
d, 210a to 210d are color-coded, respectively, so that predetermined connectors are connected to each other.

The outer slide 160 is connected to four outer balancer air cylinders 216 provided on the machine frame 196 of the press machine 150. The pressure chamber of the air cylinder 216 communicates with an air tank 218, and the air tank 218
Connecting device 2 arranged on machine frame 196 via 20, 222
24,226. These connectors 22
4, 226, respectively, the control box 2
02 is connected to the other end of each of the pressure-resistant connecting hoses 232 and 234 having one end connected to the connecting tools 228 and 230, and the air pressure Pd in the air tank 218 is detected by the air pressure sensor 236 provided in the control box 202. At the same time, the air pressure Pd is regulated by an electromagnetic ON / OFF supply / exhaust valve 238. This air pressure Pd is
Blank holder plate 158, outer slide 160
The pressure is adjusted so as to balance the weight of the wrinkle holding ring 156. The pressure chambers of the four air cylinders 216 are connected to a common air tank 218.

On the other hand, as shown in FIG. 17, the inner plunger 168 is connected to the die height adjusting mechanism 1.
72 is connected to the inner slide 164 via the same die height adjustment mechanism 240 as the servo motor 242.
Thereby adjusting the relative distance hb.
This relative distance hb is detected by a rotary encoder 244 (see FIG. 18) provided on the servomotor 242. As the relative distance hb increases, the inner slide 164 is lowered with respect to the inner plunger 168, and the press load Fp when the inner plunger 168 reaches the lower end is changed. Will be adjusted accordingly. The four inner plungers 168 are respectively connected to the die height adjustment mechanism 2.
40 is connected to the inner slide 164 via
Each relative distance hb is adjusted. A strain gauge 246 is attached to each inner plunger 168 so as to detect each load Fbi (i = 1, 2, 3, 4) acting on each inner plunger 168.

The die height adjusting mechanism 240 is integrally connected to a piston 250 of a hydraulic cylinder 248 provided to prevent overload, while a housing of the hydraulic cylinder 248 is integrally provided on an inner slide 164. ing. Hydraulic cylinder 248 has a pressure chamber filled with hydraulic oil, and the pressure chamber is communicated with oil chamber 254 of cylinder 252. Cylinder 2
52 is connected to an air tank 258, and the air tank 258 is an electromagnetic type O.
The air pressure Pg in the air chamber 256 and the air tank 258 is connected to the pressure air source 262 in the factory via the N / OFF supply / exhaust valve 260 and the ON / OFF supply / exhaust valve 260 is switched. It is being adjusted. This air pressure Pg is detected by the air pressure sensor 264. The air pressure Pg allows the piston to retreat to the air chamber 256 side and allow the die height adjustment mechanism 240 and the inner slide 164 to approach each other when an excessive load is applied to the hydraulic cylinder 248. Press machine 1 to prevent damage to the mold
The pressure is adjusted according to the pressing capacity of 50. The hydraulic cylinder 248, the cylinder 252, the air tank 258, and the like include four inner plungers 168 and one inner slide 1.
The air pressures Pg are respectively adjusted at connection portions with the air pressure Pg.

The inner slide 164 is connected to four inner balancer air cylinders 266 provided in the machine frame 196 of the press machine 150. The pressure chamber of the air cylinder 266 is communicated with an air tank 268, and the air tank 268 is turned on and off by an electromagnetic type.
The pressure air source 26 via the OFF supply / exhaust valve 270
2 and an ON / OFF supply / exhaust valve 270
Is controlled to switch between the pressure chamber and the air tank 2.
The air pressure Pf within 68 is adjusted. This air pressure Pf is detected by an air pressure sensor 272, and the inner slide 164 and the punch type 162
The pressure is adjusted to balance the weight of the vehicle. The pressure chambers of the four air cylinders 266 are connected to a common air tank 268.

The control box 202 corresponds to FIG.
As shown in FIG. 1 and FIG.
0, and is disposed on a carriage 284 capable of freely moving while gripping the handle 282, and includes a plurality of press machines 1
50 is selectively used as needed. The control box 202 includes the connection tools 204a to 204a.
204d, 206a to 206d, 228, 230,
The ON / OFF supply / exhaust valves 214a to 214d, 2
38, and is connected to the pressure air source 262 via a pressure-resistant connecting hose 288 (see FIG. 18). The air pressure sensors 212a to 212d, 23
6, five display meters 290 for analog display of the air pressures Pe and Pd, respectively, and four wrinkle holding loads Fsi and Fsi calculated from the air pressures Pe and Pd.
Display panel 29 for digital display of balancer load, etc.
2, and an adjustment switch 293 for manually adjusting the wrinkle holding load Fsi and the balancer load. The pressure-resistant connecting hose 288
And the pressure-resistant connecting hoses 208a to 208d, 210a to
210d, 232, and 234 can be stored in the storage box 294.

The control box 202 also corresponds to FIG.
As is clear from FIG. 8, a controller 296 is provided, and signals representing the air pressures Pe and Pd output from the air pressure sensors 212a to 212d and 236 are supplied to the controller 296, respectively. Controller 296
Is constituted by a microcomputer having a CPU, a RAM, a ROM, an input / output interface circuit, etc., performs signal processing according to a program stored in the ROM while utilizing a temporary storage function of the RAM, and
The switching control of the N, OFF supply / exhaust valves 214a to 214d, 238 is performed. This controller 296 has a plug 298
Is connected to an outlet in the factory by the press machine 15 through the connector 300.
The dedicated controller 302 is connected to the dedicated controller 302 for exclusive use, and necessary information is exchanged with the dedicated controller 302.

The dedicated controller 302 includes a CPU,
It consists of a personal computer with RAM, ROM, input / output interface circuit, A / D converter, etc.
Signal processing is performed in accordance with a program stored in the ROM in advance while utilizing the temporary storage function of the RAM. The air pressure sensors 264, 272, rotary encoders 176, 24
4, air pressure P output from strain gauges 178, 246
Signals representing g, Pf, relative distances ha, hb, and loads Fai, Fbi are supplied to the dedicated controller 302, respectively, and the ON / OFF supply / exhaust valves 260,
The operation states of 270, motors 174, 242 are controlled by the dedicated controller 302. In FIG. 18, motors 174, 242, strain gauges 178, 246, ON, OF
Although only one F supply / exhaust valve 260 and one air pressure sensor 264 are shown, the press machine 150
, And in the present embodiment, the same processing is performed for each of the four.

The dedicated controller 302 stores machine information unique to the press machine 150 in advance by key input or the like, and also inputs mold information unique to the mold used from the transceiver 304. . That is, the die 152 stores mold information unique to the mold and an ID having a transmission function and a battery.
A card 306 (see FIG. 15) is attached, and upon receiving a data capture signal transmitted from the transceiver 304, mold information is transmitted from the ID card 306, and the mold information is transmitted to the transceiver 304. The data is taken into the dedicated controller 302 via the CPU.

The machine information and the mold information are based on the air pressures Pd, Pe,
Information necessary for determining Pf and relative distances ha and hb, for example, is as follows. In addition, the mold information includes the type of the mold, that is, the vehicle type and the product number, the press machine used,
Information such as the process is also included. (Machine information) ・ Push-in dimension Y of piston of cylinder 188 ・ Pressure receiving area Ax of hydraulic cylinder 180 ・ Pressure receiving area Ay of oil chamber 186 of cylinder 184 ・ Pressure receiving area Az of air chamber 188 of cylinder 184 ・ Capacity Ve of air tank 190 Weight Wos of outer slide 160 including blank holder plate 158 Weight Wis of inner slide 164 Wiring pressure area of air cylinder 216 (total of four) Ad Pressure receiving area of air cylinder 266 (total of four) Af ha- Temporary characteristics of Fsi (Fsi = c · ha + d) • Temporary characteristics of hb-Fpi (Fpi = e · hb) (Die information) Load Fsoi-Press number characteristic-Subtraction value α-Stop time characteristic

Here, the drive-in dimension Y and the pressure receiving area A
x, Ay, Az, and the capacity Ve are independently determined for each of the four connecting portions that connect the outer slide 160 to the four outer plungers 166. Run-in dimension Y
Is a movement stroke of the piston of the cylinder 184 toward the air chamber 188, and is determined in advance by an experiment or the like so that the piston is driven in such a manner and wrinkle holding based on the air pressure Pe is reliably performed. Pressure receiving area Ax, A
y and Az are determined based on the operating characteristics of the hydraulic cylinders 180 and 184, and the actual pressure receiving area including the sliding resistance and the air leakage is determined. The capacity Ve includes the volume of the air chamber 188. It is obtained from a change in the air pressure Pe with respect to the movement stroke.

The weight Wos of the outer slide 160 including the blank holder plate 158 is a value obtained by subtracting the sliding resistance. And the air cylinder 2
The total load Fa-air pressure Pd characteristic of the four strain gauges 178 is obtained by changing the 16 air pressure Pd, and the weight Ws of the slide plate 20 in the above embodiment is determined from the total load Fa-air pressure Pd characteristic. It is obtained in the same way as when it is obtained. The sliding resistance can be separately set as machine information. Weight W of inner slide 164
Similarly, is is obtained from the total load Fb-air pressure Pf characteristic. Also, the pressure receiving area Ad of the air cylinder 216
Is the sum of the four air cylinders 216, taking into account the air leakage of the individual air cylinders 216. The slope of the total load Fa-air pressure Pd characteristic is represented by the pressure receiving area Ad
Is equivalent to The pressure receiving area Af of the air cylinder 266 is also the sum of the four air cylinders 266, and
66 considering the air leakage, and the total load F
The slope of the b-air pressure Pf characteristic corresponds to the pressure receiving area Af.

Ha-Fsi provisional characteristics (i = 1, 2, 3, 4)
Is a characteristic (Fsi = c · ha) between the wrinkle holding load Fsi and the relative distance ha when the outer plunger 166 reaches the lower end.
+ D), which differs depending on the rigidity of the mold used. Therefore, the strain gauge 178 is changed while the relative distance ha is variously changed by interposing a member having higher rigidity than a normal mold.
The wrinkle pressing load Fsi when the outer plunger 166 reaches the lower end is measured by
0 reflects the rigidity. When measuring the ha-Fsi temporary characteristics, the air pressure P is set so that the outer slide 160 is lowered by the outer plunger 166 in a state where the lifting force of the outer cylinder 160 and the blank holder plate 158 and the air cylinder 216 are balanced.
In addition to the adjustment of d, the wrinkle holding load Fsi changes depending on the air pressure Pe. Therefore, the air pressure Pe is set as a parameter as shown in FIG. The ha-Fsi provisional characteristic is determined based on the maximum value ha ₀ of the relative distance ha when the wrinkle holding load Fsi is 0, and is set for each of the four die height adjustment mechanisms 172, and the entire wrinkle holding mechanism 172 is set. The load Fs is the sum of the wrinkle holding loads Fsi. It is also possible to measure this ha-Fsi provisional characteristic using the load measuring device 100. For example, as shown in FIG. 25, a spacer block 120 is placed on a support 106 of a load measuring table 102, and a strain gauge The wrinkle holding load Fsi is measured by 110.

Hb-Fpi provisional characteristics (i = 1, 2, 3, 4)
Is the characteristic between the press load Fpi and the relative distance hb when the inner plunger 168 reaches the lower end (Fpi = e · hb).
Thus, the h-Fpi provisional characteristics (Fpi = a ·
This is set in the same manner as in h). Specifically, the inner plunger 168 is changed by the strain gauge 246 while changing the relative distance hb by interposing a member having higher rigidity than a normal mold.
Is measured when the pressure reaches the lower end, and reflects the rigidity of the press machine 150. This hb
-When measuring the Fpi provisional characteristics,
The air pressure Pf is adjusted such that the inner slide 164 is lowered by the inner plunger 168 in a state in which the lifting force of the air cylinder 268 is balanced with the lifting force. The hb-Fpi provisional characteristics are determined for each of the four die height adjustment mechanisms 240, and the total press load Fp is the sum of the individual press loads Fpi. In addition, as shown in FIG.
Using 00, the press load Fpi can also be measured from the output of each strain gauge 112.

The wrinkle holding ring 15 in the mold information
The weight Wr of No. 6 and the weight Wq of the punch die 162 are measured values measured after manufacturing the wrinkle holding ring 156 and the punch die 162. Press load Fpoi (i = 1,
2, 3, 4) are a punch type 162 and a die type 152.
Is mounted on a test tri-press for testing and the actual press working is performed, and the load conditions for obtaining an appropriate press-formed product are obtained by trial and error. The influence is eliminated. For example, when a tri-press configured similarly to the press machine 150 in FIG.
4 and the weight of the punch die 162 and the lifting force of the air cylinder 266 are balanced.
The press load Fpoi is obtained based on the loads Fbi detected by the respective strain gauges 246 when the air pressure Pf is adjusted so that 4 can be lowered by the inner plunger 168 and press working is performed in that state. The press load Fpoi is the load at each of the four locations connected to the plunger 168, and the total press load Fpo is the sum of the press loads Fpoi at the four locations.

The wrinkle holding load Fsoi-the number of times of pressing (i
= 1,2,3,4), as in the case of the press load Fpoi described above, is not affected by the weight of the mold and the sliding resistance of each part of the tri-press, etc. The wrinkle holding load Fsoi at which the product is obtained is obtained in relation to the number of presses. This is the first
As in the example, it was considered that the mold temperature rises due to the heat generated by the passage resistance μ in the wrinkle holding portion, and the tension Te increases due to the increase in the passage resistance μ due to changes in lubrication conditions and the like. It is obtained by continuously performing press working on a press material having the same lubricating conditions as in the case of mass production, based on the temperature change, the state of occurrence of cracks, and the like. Table 2 is an example, and the wrinkle pressing load Fsoi is determined for each load number N corresponding to the number of presses in the same manner as in Table 1, but in this embodiment, the die height adjusting mechanism 1 is used.
Each of the strain gauges 178 is provided for each of the four wrinkle holding load adjusting portions provided with the cylinder 72, the cylinder 184, and the like.
Is separately set based on the measured load Fai.

[0077]

[Table 2]

Also, the subtraction value α-stop time characteristic indicates that even if the lubrication conditions and the like change due to the decrease in the mold temperature due to the stoppage of the press machine and the passage resistance μ decreases, proper press working can be performed when the press is restarted. As described above, the subtraction value α of the load number N is determined so as to increase the wrinkle pressing load Fsoi according to the stop time of the press machine. The subtraction value α-stop time characteristic is also obtained experimentally in advance in the same manner as in the first embodiment, and is set in the same manner as in FIG. A different subtraction value α-stop time characteristic can be set for each of the four wrinkle holding load adjusting units.

Returning to FIG. 18, the dedicated controller 302
In addition, limit switch 276, start switch 27
8 are connected. The limit switch 276 is turned ON when the outer plunger 166 of the press machine 150 reaches the lower end, and outputs a press signal SP to the dedicated controller 302 every time press work is performed once. The start switch 278 is turned on and off by an operator when starting and stopping the press working, and outputs a start signal SS indicating the ON state to the dedicated controller 302.

The controller 296 executes the functions shown in FIG. 19 by performing signal processing according to a program predetermined in the ROM. In FIG. 19, the machine information memory 310
Is for reading and storing machine information pre-stored in the dedicated controller 302. The die information memory 312 has a die mounted on the press machine 150 and is read from the ID card 306 by the transceiver 304. Remember die information. Further, based on the machine information stored in the machine information memory 310 and the mold information stored in the mold information memory 312, the air pressure Pdx calculation block 314 calculates the outer slide 160, the blank holder plate 158, and the blank holder. The air pressure Pdx that lifts the rings 156 with a force that balances them is given by the following equation (1).
0). Air pressure Pd adjustment block 316
Controls the ON / OFF supply / exhaust valve 238 so that the air pressure Pd in the air tank 218 detected by the air pressure sensor 236 becomes the calculated air pressure Pdx.
Thus, the press working can be performed with the wrinkle holding load Fsoi set as the mold information without being affected by the weights of the outer slide 160, the blank holder plate 158, and the wrinkle holding ring 156. The capacity of the air tank 218 is sufficiently large, and the change in the air pressure Pd caused by the change in the capacity of the four air cylinders 216 due to the lowering of the outer slide 160 is almost negligible. The pressure Pdx can also be calculated.

[0081]

Pdx = (Wr + Wos) / Ad (10)

The air pressure Pex calculation block 318a calculates the air pressure Pex from the relationship of the following equation (11) based on the machine information and the mold information. The wrinkle holding load Fsoi used in the equation (11) is an air value from the four wrinkle holding loads Fsoi of the load number N = 1 in the wrinkle holding load Fsoi-press number characteristic set in Table 2 set as the mold information. The one corresponding to the pressure Pex calculation block 318a is read. The four wrinkle holding loads Fsoi set in the wrinkle holding load Fsoi-press number characteristics correspond to the four air pressure Pex calculation blocks 318a to 318d, in other words, correspond to the four wrinkle holding load adjustment units. Is set. Air pressure Pe adjustment block 320a
Controls the ON / OFF supply / exhaust valve 214a so that the air pressure Pe in the air tank 190 detected by the air pressure sensor 212a becomes the calculated air pressure Pex. The air pressure Pex is equal to the other three air tanks 190.
Are also calculated based on the machine information and the mold information, respectively, and while the signals of the air pressure sensors 212b to 212d are taken in, the ON / OFF supply / exhaust valves 214b to 214b are taken.
By controlling the switching of 4d, the air pressure Pe at four locations is adjusted. The controller 296 includes air pressure Pex calculation blocks 318b to 318d and air pressure adjustment blocks 320b to 320d for that purpose. By controlling the air pressures Pe in the four air tanks 190 in this manner, the wrinkle holding load can be performed with the wrinkle holding load Fsoi shown in Table 2 in each wrinkle holding load adjustment unit. become. The air pressure Pex calculation blocks 318a to 318d calculate the air pressure Pex.
In the initial setting, it is determined in advance that the wrinkle holding load Fsoi having the load number N = 1 is read from the wrinkle holding load Fsoi-the number of times of pressing and the air pressure Pex is calculated. The air pressure Pex calculation blocks 318c, 318
d and the air pressure adjusting blocks 320c and 320d are not shown. Pt in the equation (11) is the atmospheric pressure.

[0083]

Fsoi = (Ax · Az / Ay) {(Pex + Pt) [Ve / (Ve−Az · Y)] − Pt} (11)

On the other hand, the dedicated controller 302
By performing signal processing according to a program predetermined in the OM, the functions shown in FIG. 20 are executed. In FIG. 20, the machine information memory 322 stores machine information previously input by key input or the like.
A die is attached to the press machine 150, and the die information read from the ID card 306 by the transceiver 304 is stored. The air pressure Pfx calculation block 326 is
Based on the machine information and the mold information, an air pressure Pfx for lifting the inner slide 164 and the punch mold 162 with a force that balances them is calculated according to the following equation (12). The air pressure Pf adjustment block 328 is turned on and off so that the air pressure Pf in the air tank 268 detected by the air pressure sensor 272 becomes the calculated air pressure Pfx.
The switching control of the F supply / exhaust valve 270 is performed. Thus, the press working can be performed with each press load Fpoi set as the mold information without being affected by the weight of the inner slide 164 and the punch mold 162.
The capacity of the air tank 268 is sufficiently large, and the change in the air pressure Pf caused by the change in the volume of the four air cylinders 266 accompanying the lowering of the inner slide 164 is almost negligible. The pressure Pfx can also be calculated.

[0085]

Pfx = (Wq + Wis) / Af (12)

The relative distance ha adjustment block 330 has four die heights based on the machine information and the mold information so that the press working is performed with each wrinkle pressing load Fsoi of Table 2 set as the mold information. The relative distance ha of the adjusting mechanism 172 is adjusted independently of each other.
With blank-holding force Fsi determines the reference value ha ₀ is the maximum value of the relative distance ha when the 0 on the basis of the load Fai supplied from the strain gauge 178, shown in FIG. 23, which is set as the machine information ha- Fsi provisional characteristics (Fsi = ch
a + d), the air pressure Pex calculation block 318
The one corresponding to the air pressure Pex obtained in a to 318d is selected. Then, based on the selected ha-Fsi temporary characteristic, along with determining the relative distance ha ₁ that the blank-holding force Fsoi is obtained as shown in FIG. 24, the reference value ha
_The relative distance ha by the servomotor 174 based on ₀
It was adjusted to ha _1, to measure the blank-holding force Fs ₁ based on the signal supplied from the strain gauge 178 when the test pressing is performed in that state. Preset ha-Fsi
Temporary property, since rigidity than conventional mold is set based on the case high, generally blank-holding force Fs ₁ is smaller than the blank-holding force Fsoi, on the basis of the difference ha-
While obtaining the Fsi characteristic (Fsi = c · ha + f),
The relative distance hax at which the wrinkle holding load Fsoi is obtained is determined from the ha-Fsi characteristic, and the servo motor 174 controls the relative distance ha to be hax. Wrinkle holding load Fsoi used for adjusting the relative distance ha.
In the same manner as the air pressure Pex calculation blocks 318a to 318d, data of the load number N = 1 in Table 2 is read, and although not shown, four die height adjustment mechanisms 1 are provided.
72, the relative distance ha is adjusted in the same manner as described above. Thus, regardless of the difference in the rigidity of each press machine 150 and the difference in the rigidity of each part in one press machine 150, the load number N = 1 in Table 2 is shown in each of the four wrinkle holding load adjusting units. The wrinkle holding is performed with each wrinkle holding load Fsoi.

The relative distance hb adjustment block 332
Adjusts the relative distances hb of the four die height adjustment mechanisms 240 independently based on the machine information and the mold information so that the press working is performed with each press load Fpoi set as the mold information. It has exactly the same function as the relative distance h adjustment block 146 in the above embodiment.

The dedicated controller 302 separates the four loads Fbi detected by the strain gauges 246 from the overload prevention loads Foli (i = 1, 2, 3, 3) separately from the above-described respective controls. The air pressure Pg is controlled in the same manner as the control of the air pressure Pc in the above embodiment so as not to exceed 4). Since the air pressure Pg can be set irrespective of the mold to be used, it may be adjusted in advance by manual operation or the like.

As described above, also in the press machine 150 of this embodiment, the machine information unique to the press machine 150 previously stored in the machine information memory 322 and the mold unique to the mold read from the ID card 306 via the transceiver 304 are used. Based on the mold information, regardless of the differences in the rigidity of each press machine and the sliding resistance of each part, etc.
That is, the air pressures Pdx and Pe, which are the press working conditions, are set so that the wrinkle holding load Fsoi and the press load Fpoi are reproduced.
x, Pfx, relative distances hax, hbx are obtained, and the air pressures Pd, Pe, Pf,
Since the relative distances ha and hb are automatically initialized, troublesome adjustment work due to trial and error is eliminated, the burden on the operator is greatly reduced, and excellent quality press molded products are stabilized. Will be obtained.

On the other hand, in the present embodiment, the air pressures Pd, Pe
Pressure sensors 212a-2 necessary for automatically adjusting the pressure
12d, 236 and ON / OFF supply / exhaust valves 214a-
Since 214d and 238 are arranged in the control box 202 and can be freely moved and connected to each press machine 150, their air pressure sensors and O
The same control can be easily performed on a press machine that does not include the N, OFF supply / exhaust valve. Also,
For example, in order to explain the effect of stabilizing the press quality by the automatic pressure control of the air pressures Pd and Pe, etc., the control box 202 is taken to factories in various places to perform demonstrations, or only the necessary press machine is used. It is suitably used in a press working line or the like in which a press operation is performed while operating. Further, the wrinkle pressing load Fsi at four points, the balancer load by the air cylinder 216, and the like can be manually adjusted, and the air pressures Pe and Pd that generate such loads are displayed on the display meter 290.
The present invention can also be suitably used when performing abnormality diagnosis or the like of a press machine.

The air pressures Pd, Pe, Pf and the relative distances ha, hb are not necessarily strictly the air pressures Pdx, Pex,
It is not necessary to perform control so that Pfx and the relative distances hax and hbx coincide with each other, and it is only necessary to perform control so as to fall within a predetermined allowable range that satisfies the required press quality. The same is true.

On the other hand, after the air pressures Pd, Pe, Pf and the relative distances ha, hb are automatically initialized based on the mold information and the machine information, the press-formed product is actually formed by the press machine 150. In the case of mass production, the air pressure Pe is changed according to the number of presses and the stop time. That is, the controller 296 includes a load number N change block 340, and the limit switch 276, the start switch 278 and the dedicated controller 30.
Press signal SP and start signal S supplied via
The number of presses and the stop time are calculated based on S, and the air pressure Pex
In the calculation blocks 318a to 318d, the load number N for reading the wrinkle pressing load Fsoi from Table 2 is changed. The air pressure Pex calculation blocks 318a to 318d read the wrinkle holding load Fsoi according to the load number N thus changed, and calculate the air pressure Pex, while the air pressure Pe adjustment blocks 320a to 320d calculate the air pressure Pex. The air pressure Pe is adjusted in accordance with. As a result, the wrinkle holding loads Fsi at the four wrinkle holding load adjustment sections are respectively raised and lowered as indicated by arrows Q in FIG.
The wrinkle holding load Fsoi at the load number N set at 40 is set. The specific contents of the load number N change block 340 are the same as those of the first embodiment,
Signal processing is performed according to the flowchart of FIG.

Therefore, also in this embodiment, the wrinkle holding load Fsoi is reduced in accordance with the wrinkle holding load Fsoi-pressing number characteristic shown in Table 2 according to the number of presses, and the air pressure Pe is correspondingly reduced and the stoppage is stopped. The wrinkle holding load Fsoi is increased in accordance with the subtraction value α-stop time characteristic of FIG. 11 according to the time, and the air pressure P
Since e is raised, an appropriate press-formed product without wrinkles or cracks is always produced regardless of the variation of the passage resistance μ due to the temperature change of the mold. Further, since the wrinkle pressing load Fsoi, that is, the air pressure Pe, is reduced in accordance with the number of times of press, the abrasion of the mold due to the excessive tension Te is prevented, and the calorific value Qs is reduced to reduce the heat dissipation. Since the mold temperature to be balanced is low, the influence of heat on the entire press working is reduced.

This embodiment is an embodiment of the first invention and the second invention, and includes a load number N changing block 340.
And the air pressure Pex calculation blocks 318a to 318d correspond to wrinkle pressing load control means, and the air pressure Pe adjustment blocks 320a to 320d and the ON / OFF supply / exhaust valve 2
14a to 214d and the air pressure sensors 212a to 212d correspond to wrinkle holding load adjusting means. 6 and the limit switch 276 constitute the number-of-presses detecting means. The timer TI reset in step S6 and the timer TI in step S6 when the press machine 150 is stopped. Steps S1 and S2 for inhibiting the execution correspond to the clocking means.

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

For example, in the first and third embodiments, each time the number of presses exceeds a certain number Co, the wrinkle holding load F
Although the s and Fsi were changed, the wrinkle holding load F was changed by changing the wrinkle holding load with a relatively small number of presses at the beginning of the press working in which the temperature change was relatively large.
The modification of s and Fsi is determined as appropriate.

In the first and third embodiments, the number of presses is detected using the limit switches 124 and 276 which are turned on when the plungers 22 and 166 reach the lower end. Press machine 10,150
Various other press frequency detecting means, such as detecting the press frequency from the rotation angle of the crankshaft, can be adopted.

In the second embodiment, the press-formed product 3
Although the temperature of the upper surface of the press-formed product 54 is measured, the temperature of the lower surface of the press-formed product 354 may be measured, or the temperature of the wrinkle pressing surface of the die 18 and the wrinkle pressing ring 30 may be measured. For example, the temperature measurement site may be appropriately determined in consideration of the structure of the press machine, the plating conditions of the mold, and the like.

In the second embodiment, the radiation thermometer 35
Although the reference numeral 0 is attached to the machine frame 78 of the press machine 10, it may be provided on the bolster 14, the slide plate 20, the punch mold 12, the die mold 18, or the like.

In the second embodiment, the third invention is applied to the single-action press machine 10. However, the third action is also applied to the double-action press machine 150 as in the third embodiment. It goes without saying that the invention can be applied. In that case, the temperature may be measured at each of four places where the wrinkle holding load can be adjusted, and the wrinkle holding load may be changed according to the temperature of each part.

In the above embodiment, the mold information is stored in the ID cards 96 and 306, and the controller 90 and the
Although read by the dedicated controller 302, the mold information is recorded on a barcode, a magnetic tape, a floppy disk, or the like, and the contents are read by a reader or the like connected to the controllers 90 and 302. You may do it. It is also possible to manually input mold information using a keyboard or the like.

In the above embodiment, the initial values such as the air pressures Pa and Pe are automatically set. However, the air pressures Pa and Pe are determined by trial and error so that a proper press-formed product can be obtained. The present invention can be similarly applied to a case where an initial value such as Pe is set. That is, the change amount ΔFs of the wrinkle holding load is set in accordance with the number of presses and the temperature change. It is sufficient to change the air pressure Pa by the pressure ΔPa,
It is not always necessary to know the initial set values of the wrinkle holding loads Fs and Fsi.

[0103]

ΔPa = ΔFs / Aa (13)

In the third embodiment, the air pressure Pe is adjusted in order to change the wrinkle pressing load Fsi according to the number of presses and the stop time. (Ha + f), the relative distance ha of the die height adjustment mechanism 172 may be adjusted.

In the third embodiment, the air pressures Pd, Pd
e, air pressure sensors 236, 212a to 212d and ON / OFF supply / exhaust valves 238, 214a to 21
4d is provided in the control box 202 which is formed separately from the press machine 150, but the air pressure P
f, the air pressure sensor 272 and the ON / OFF supply / exhaust valve 270, etc.
02. The air pressure sensors 236, 212a to 212d and the ON / OFF supply / exhaust valves 238, 214a to 214d are
0 of the first embodiment and the second embodiment.
The air pressure sensors 50 and 86 and the ON / OFF supply / exhaust valves 46 and 84 of the embodiment can be provided in a control box or the like that is configured separately from the press machine 10.

In the above-described embodiment, the four air cylinders 80, 216, and 266 for the balancer are connected to the common air tanks 82, 218, and 268, respectively. The air pressure may be adjusted independently.
The configuration of the press machines 10, 150 can be changed as appropriate.

Each of the arithmetic expressions (6) to (12) described in the above embodiment is merely an example, and the air pressure P
a or the like may be required.

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 corresponding to claims of the present invention.

FIG. 2 is a configuration diagram showing an example of a single action press machine in which a wrinkle holding load is changed by the wrinkle holding load automatic changing device of the present invention.

FIG. 3 is a configuration diagram showing a portion near a balancer air cylinder of the press machine in FIG. 2;

FIG. 4 is a block diagram illustrating a control system of the press machine in FIG. 2;

FIG. 5 is a block diagram illustrating functions of a controller in FIG. 4;

FIG. 6 is a flowchart illustrating the specific contents of a load number N change block in FIG. 5;

FIG. 7 is a diagram illustrating one mode of load measurement for obtaining machine information of the press machine in FIG. 2;

8 is a diagram showing an example of a load waveform obtained by the load measurement of FIG.

9 is a diagram showing a relationship between a wrinkle holding load Fsi obtained by the load measurement of FIG. 7 and an air pressure Pa.

10 is a diagram showing a relationship between a press load Fpi of the press machine of FIG. 2 and a relative distance h.

11 is a diagram illustrating an example of a subtraction value α-stop time characteristic input as mold information in the press machine of FIG. 2;

FIG. 12 is a configuration diagram showing another example of a single action press machine in which the wrinkle holding load is changed by the wrinkle holding load automatic changing device of the present invention.

13 is a diagram showing an example of a wrinkle holding load Fso-temperature θ characteristic input as mold information in the press machine of FIG.

FIG. 14 is a block diagram illustrating functions of a controller in the press machine of FIG.

FIG. 15 is a configuration diagram showing an example of a double action press machine in which a wrinkle holding load is changed by the wrinkle holding load automatic changing device of the present invention.

16 is a configuration diagram showing a portion near an air cylinder for an outer-side balancer of the press machine in FIG.

17 is a configuration diagram showing a portion near an air cylinder for an inner-side balancer of the press machine in FIG.

FIG. 18 is a block diagram illustrating a control system of the press machine in FIG.

FIG. 19 is a block diagram illustrating functions of a controller in FIG. 18;

20 is a block diagram illustrating functions of a dedicated controller in FIG.

FIG. 21 is a front view showing the control box shown in FIG. 18;

FIG. 22 is a left side view of the control box in FIG. 21.

23 is a diagram showing a relationship between a wrinkle pressing load Fsi and a relative distance ha of the press machine in FIG.

24 is a diagram illustrating a method of obtaining a relative distance hax based on the load characteristics in FIG.

FIG. 25 is a diagram illustrating one mode of load measurement for obtaining machine information of the press machine in FIG.

[Explanation of symbols]

10: Press machine 46: ON / OFF supply / exhaust valve (wrinkle holding load adjusting means) 50: Air pressure sensor (wrinkle holding load adjusting means) 90: Controller 124: Limit switch (pressing frequency detecting means) 134: Air pressure Pax calculation Block (wrinkle holding load control means) 136: Air pressure Pa adjustment block (wrinkle holding load adjustment means) 148: Load number N change block (wrinkle holding load control means) 150: Press machine 212a to 212d: Air pressure sensor (wrinkle holding) Load adjustment means) 214a to 214d: ON / OFF supply / exhaust valve (wrinkle press load adjustment means) 276: Limit switch (press number detection means) 296: Controller 318a, 318b: Air pressure Pex calculation block (wrinkle press load control means) 320a, 320b: Air pressure Pe adjustment block 340: Load number N change block (Wrinkle holding load control means) 350: Radiation thermometer (Temperature detecting means) 356: Wrinkling holding load Fso setting block (Wrinkle holding load control means) 358: Air pressure Pax Calculation block (wrinkle holding load control means) Steps S1, S2, S6: time measurement means Steps S7, S8: press frequency detection means

Claims (3)

(57) [Claims] An apparatus for automatically changing a wrinkle holding load at the time of performing said wrinkle holding in a press machine which performs drawing while performing wrinkle holding, comprising: a wrinkle holding load adjustment for adjusting said wrinkle holding load. Means, a number-of-presses detecting means for counting the number of presses in which press working is continuously performed by the press machine, and the wrinkle pressing load decreases as the number of presses counted by the number-of-presses detecting means increases. A wrinkle holding load control means for controlling the wrinkle holding load adjusting means. 2. A wrinkle press load adjusting device for automatically changing a wrinkle press load at the time of performing said wrinkle press in a press machine which performs drawing while performing wrinkle press. Means, number-of-presses detecting means for counting the number of presses in which press working is continuously performed by the press machine, time-measuring means for measuring the stop time of the press machine, and presses counted by the number-of-presses detecting means A wrinkle holding load control unit that controls the wrinkle holding load adjusting unit so that the wrinkle holding load decreases as the number of times increases and the wrinkle holding load increases as the stop time measured by the timing unit increases. An automatic wrinkle holding load changing device for a press machine, comprising: 3. A wrinkle press load adjusting device for automatically changing a wrinkle press load at the time of performing said wrinkle press in a press machine for performing drawing while performing wrinkle press. Means, a temperature detecting means for measuring the temperature of the wrinkle holding portion where the wrinkle holding is performed, and the wrinkle holding load decreases as the temperature of the wrinkle holding portion measured by the temperature detecting means increases. An automatic wrinkle holding load changing device for a press machine, comprising: a wrinkle holding load control means for controlling a holding load adjusting means.