JPH06344200A - Adjusting method for slide height of press, and mounting method for press upper die - Google Patents

Abstract

PURPOSE:To reduce the number of trial punching, to improve a working rate, and to reduce a worker's burden by attaining correlation between a driving into quantity and a press load with a proximate linear line, and adjusting the slide height of a press so that a target press load is attained. CONSTITUTION:At the time of installing a press upper die, a press automatically stops lowering when a press load Fpt becomes a set load F0. The press upper die is installed on a press slide to detect a press stroke. After that, the press slide is allowed to ascend, and a slide height is changed according to a press stroke so that a driving into quantity at the bottom read point becomes larger than a driving into quantity at the time of installing the upper die by an additional driving into quantity X0. A driving into change quantity X1 by which a desired target press load Ff0 is attained by a proximate linear line from press loads F0 and F1 at the bottom dead point and the additional driving into quantity X0 is attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press machine, and more particularly to a slide height adjusting method for adjusting a slide height so that a desired press load can be obtained with a small number of trial hits, and an excessive load to the press machine. The present invention relates to a method for attaching a press upper die that attaches a press upper die to a press slide without operating it.

[0002]

2. Description of the Related Art A press slide is provided which is connected to an up-and-down driving member and can be moved up and down, and whose height is adjusted by a height adjusting mechanism provided at a connecting portion with the up-and-down driving member. A press machine that vertically moves a press upper die attached to the press lower die to perform press working with a press lower die is often used for press working of an automobile body and the like. FIGS. 1 and 2 show an example of a single action type press machine for performing drawing work, in which wrinkling work is carried out by a wrinkle holding ring 30 and drawing work is carried out by a die mold 18 and a punch mold 12. The press slide 20 to which the die die 18 is attached is connected to a plunger 22 as a vertical drive member via a die height adjusting mechanism (height adjusting mechanism) 52, and adjusts a relative distance h ₁ (corresponding to the slide height). By doing so, the press load, in this case the forming load, can be changed. Since the press load that can perform appropriate press working differs depending on each mold, it is necessary to adjust the relative distance h ₁ for each mold to be used, and it is necessary to visually check to obtain a desired pressed product. It is normal to make trial shots while observing and adjust by trial and error.

On the other hand, there is one in which a strain sensor is attached to a frame supporting the press slide or a vertical driving member for moving the press slide up and down, and the strain can be detected to measure the press load. JP-A-57-30
The device described in Japanese Patent No. 919 and the device described in Japanese Patent Application No. 4-322405 filed previously by the applicant of the present application are examples thereof, and the strain sensor uses a permanent magnet and a Hall element. There are also dial gauge type, capacitance type, strain gauge type, optical type, differential transformer type, rotary encoder type and so on. In a press machine capable of measuring a press load in this way, for example, an appropriate press load is obtained in advance by a tri-press when manufacturing a die, and the press load detected by the strain sensor is an appropriate press load during press working on a production line. By adjusting the relative distance h ₁ so as to substantially match, a pressed product of constant quality can always be obtained.

The above-mentioned relative distance h ₁ is adjusted every time the die is replaced, but when a new die is attached to the press machine, the upper press is placed on the lower press die (the punch die 12 in FIG. 1). After arranging the molds (the die mold 18 in FIG. 1) on the moving bolster in a stacked state, the moving bolster is moved to the mold arrangement position of the press machine and positioned, and the vertical drive member is lowered and the press is performed. The slide is stopped at a position where it abuts on the press upper die, and in that state, the press upper die is attached to the press slide. Stopping the lowering of the vertical drive member is performed by an operator visually observing the contact between the press slide and the press upper die and stopping the press machine by operating a switch. The adjustment of the relative distance h ₁ is performed separately from the mold replacement after the completion of the mold replacement.

[0005]

However, the relative distance h ₁ is adjusted while visually observing so as to obtain a desired pressed product, and the press load detected by the strain sensor is set to a predetermined proper press load. Since the work of adjusting the relative distance h ₁ so that they substantially match each other is performed by trial and error by performing trial striking many times, it takes time to make the adjustment and it is an obstacle to achieving full automation of press working. Was becoming.

When the upper press die is attached to the press slide during die replacement, the operator visually observes the contact between the press slide and the upper press die while lowering the vertical drive member, and operates the switch. Although it was designed to stop the press machine, it requires skill, and if the switch operation is delayed, an excessive load may be applied to the press machine, which may damage the press machine such as seizure of the drive motor. It was

The present invention has been made in view of the above circumstances. A first object of the present invention is to provide a slide height (relative distance) so that a desired press load can be obtained with a small number of trial hits.
The second purpose is to enable the upper press die to be attached to the press slide without applying an excessive load to the press machine.

[0008]

In order to achieve the above-mentioned first object, a first aspect of the present invention is connected to an up-and-down driving member and moved up and down, and at the connecting portion with the up-and-down driving member. In a press machine including a press slide whose height is adjusted by a height adjusting mechanism provided, and performing a press working between a press upper die attached to the press slide and a press lower die, The height of the press slide is adjusted by the height adjusting mechanism so that a predetermined target press load is obtained while the press load is detected by the load detection means and the stroke position of the vertical drive member is detected by the stroke position detection means. A method of adjusting, comprising: (a) a lowering step of lowering the vertical drive member and stopping the vertical drive member at a position where a predetermined press load is generated; b) an ascending step of ascending the vertical drive member to separate the press upper die from the press lower die; and (c) a pressing load when the press slide is stopped to descend by the first press in the descending step. As the load, a height change amount by which the first press load is obtained when the vertical drive member is lowered to the bottom dead center position is obtained based on the stroke position of the vertical drive member at the time when the vertical movement is stopped. A first height changing step of changing the height of the press slide by a dimension obtained by adding a predetermined first additional change amount to the height change amount; and (d) the vertical movement in a state in which the height of the press slide is changed. A second press load detection step of driving the drive member to detect the press load at the bottom dead center position as a second press load, and (e) the first press load, the second press load, and the first drive-in. Based on Sararyou, the determined by linear approximation the correlation between the thrust quantity and the press load of the press slide, to calculate the second drive-changing amount where the target pressing force from the correlation is obtained,
And a second height changing step of changing the height of the press slide by the second amount of change for pushing in.

[0009]

[Operation] In such a slide height adjusting method,
First, in the lowering step, the vertical driving member is lowered and stopped at a position where a predetermined press load is generated, in other words, a position where the upper press die is pressed by the lower press die.
To stop the vertical drive member from descending, the operator operates the switch by visually observing the contact state between the press upper die and the press lower die, or by observing the display of the press load detected by the load detecting means. However, in order to avoid applying an excessive load to the press machine, it should be automatically stopped when the press load detected by the load detecting means reaches a predetermined value. Is desirable. This lowering step can also be performed separately from the die replacement after the upper die is attached to the press slide by the die exchange, but in order to attach the upper die to the press slide when exchanging the die, press down The step of lowering the vertical drive member to the position where the slide comes into contact with the press upper die may be directly used as the lowering step.

In the next raising step, the vertical driving member is raised to separate the upper press die from the lower press die. When the lowering step is executed by using die exchange, the press die may be attached to the press slide prior to the raising step. Then, in the first height changing step executed in the separated state, the press load at the time of stopping the descending is set as the first press load, and the vertical driving member is moved based on the stroke position of the vertical driving member at the time of stopping the descending. The height change amount that obtains the first press load when it is lowered to the bottom dead center position is obtained, and the height change amount is set to a predetermined first amount.
The height of the press slide, that is, the slide height, is changed by the dimension including the additional change amount.

The first amount of change in pushing may be a predetermined constant value, but instead of the upper press die and the lower press die, a load measuring table having higher rigidity is used to press the press die. A temporary correlation between the slide-in amount and the press load may be obtained in advance, and the drive-in change amount that obtains the target press load, for example, may be obtained as the first drive-in change amount from the temporary correlation. First of FIG.
The close-in change amount x ₀ is a case where a constant value is set in advance, and the load F ₀ corresponds to the first press load. Further, the solid line A in FIG. 16 is an example of the temporary correlation, the load F ₀ corresponds to the first press load, and the first drive change amount x ₀ is the temporary correlation so that the target press load Ffot can be obtained. It is the value obtained from A. This tentative correlation differs from one press machine to another due to differences in sliding resistance and rigidity of each part of the press machine.

With the slide height thus changed, the vertical driving member is driven to execute the second press load detecting step, and the press load at the bottom dead center position is detected as the second press load. In this case, when the first amount of change in pushing is determined such that the target press load is obtained from the temporary correlation, the second press load becomes a value larger than the target press load, and the second press load is applied to the press machine. No excessive load is applied. That is, since the temporary correlation is obtained by using a load measuring stand having higher rigidity than the press die, the actual correlation when the press die is attached is more than the provisional correlation. Even if the slide height is changed in order to obtain the first press change amount by which the target press load is obtained and the change ratio of the load is small, the actual press load, that is, the second press load becomes lower than the target press load. is there. In FIG. 16, the load F ₁ corresponds to the second press load. It should be noted that the first additional change amount obtained from the tentative correlation does not necessarily have to be a value at which the target press load can be obtained, and may be set so that a press load equal to or less than the target press load can be obtained. On the other hand, when a constant value is set in advance as the first drive-in change amount, it is desirable to set a relatively small value in order to avoid applying an excessive load to the press machine. In FIG. 14, the load F ₁ corresponds to the second press load.

Thereafter, a second height changing step is executed, and the correlation between the pushing amount of the press slide and the pressing load is linear based on the first press load, the second press load, and the first pushing change amount. A second close-up change amount by which the target press load is obtained is calculated from the approximation, and the slide height is changed by the second close-up change amount. With this, it is possible to basically perform press working with the target press load, but since the above linear approximation may not always be accurate, if necessary, further trial punching is performed to detect the press load and linear approximation is performed. You can also correct the slide height with, for example. The solid line in FIG. 14 and the alternate long and short dash line B in FIG. 16 are the correlations obtained by linear approximation,
x ₁ corresponds to the second additional change amount. In addition, when the first insertion change amount that obtains the target press load is obtained based on the temporary correlation, the second press load becomes a value close to the target press load, and therefore, as the first insertion change amount. Compared to the case where a fixed value is set in advance, the linear approximation error is small.

[0014]

As described above, according to the first aspect of the present invention, the correlation between the driving amount and the pressing load is obtained from the two points of the first pressing load and the second pressing load which differ in the driving amount by the first driving changing amount. The relationship is calculated by linear approximation, and the height of the press slide is adjusted so that the target press load can be obtained from the correlation, so the slide height can be obtained so that the predetermined target press load can be obtained with a small number of trial shots. Can be adjusted, the burden on the operator can be significantly reduced, the adjustment time can be shortened, and the operating rate of the press machine can be improved. Also,
Since it is possible to easily perform each of the above steps automatically by a control device or the like, it is possible to automate this to save labor in the press work.

[0015]

In order to achieve the above-mentioned first object, a second aspect of the present invention is connected to an up-and-down driving member and moved up and down, and at the connecting portion with the up-and-down driving member. In a press machine including a press slide whose height is adjusted by a height adjusting mechanism provided, and performing a press working between a press upper die attached to the press slide and a press lower die, The height of the press slide is adjusted by the height adjusting mechanism so that a predetermined target press load is obtained while the press load is detected by the load detection means and the stroke position of the vertical drive member is detected by the stroke position detection means. A method of adjusting, comprising: (a) a die placement work in which the upper die of the press is placed in a die placement position of the press machine in a state of being superposed on the lower die of the press. When lowers the upper and lower drive member while detecting the press load by (b) the load detecting means,
A descending step of automatically stopping descending at a position where the press slide comes into contact with the press upper die and the press load becomes a predetermined first press load, and (c) the press slide is stopped descending in the descending step. The upper press die is attached to the press slide in a pressed state, and (d) the vertical drive member is raised to separate the upper press die attached to the press slide from the lower press die. And (e) based on the stroke position of the vertical drive member when the press slide is stopped to descend in the lowering process, the vertical drive member is lowered to the bottom dead center position. Obtain the height change amount to obtain the first press load, and add the height of the press slide by the dimension obtained by adding the predetermined first change amount to the height change amount. A first height changing step of further, (f)
The vertical drive member is driven in a state where the height of the press slide is changed, and the press load at the bottom dead center position is set to the second value.
A second press load detection step of detecting as a press load,
(G) Based on the first press load, the second press load, and the first press change amount, the correlation between the press slide press amount and the press load is obtained by linear approximation,
A second height changing step of calculating a second close-up change amount by which the target press load is obtained from the correlation and changing the height of the press slide by the second close-up change amount. To do.

[0016]

According to the second aspect of the present invention, the step of lowering the vertical drive member to the position where the press slide contacts the upper press die in order to attach the upper press die to the upper press die at the time of exchanging the die is a lowering step. Then, first, in the die disposing step, the upper press die is placed at the die disposing position in a state of being superposed on the lower press die, and the lowering step is executed in that state. In the descending step of the second invention, the vertical drive member is lowered while detecting the press load by the load detecting means, and the press slide comes into contact with the press upper die to bring the press load to a predetermined first press load. The descent is automatically stopped at, and it is possible to avoid applying an excessive load to the press machine. Then, the upper press die attaching step is executed in the state where the lowering is stopped, the upper press die is attached to the press slide, and thereafter, the slide height is adjusted in the same manner as the first invention. In the descending step, the descending stop is performed at a position that becomes the first press load, and the slide height is adjusted using the first press load, but the actual descending stop is caused by an operation delay or the like. When there is a possibility that the pressing load at the time of the descent may be different from the first pressing load, it is desirable to perform the height adjustment by using the pressing load at the time of the actual descent stop as the first pressing load.

[0017]

According to the second invention, according to the first invention,
In addition to obtaining the same effect as the invention, the slide for the slide is made because the press load at the time of mounting the press upper die at the time of die replacement is used as the first press load to obtain the correlation between the driving amount and the press load. The time required for mold replacement including height adjustment can be shortened. Further, in the lowering process, since the lowering is automatically stopped at the position where the press load becomes the predetermined first press load, the work can be stopped as compared with the case where the lowering is stopped by the operator's switch operation. The burden on the operator is reduced, and there is no fear that an excessive load acts on the press machine to cause damage such as seizure of the drive motor.

[0018]

In order to achieve the above-mentioned second object, a third aspect of the present invention comprises a press slide which is connected to an up-and-down driving member and can be moved up and down, and is attached to the press slide. In a press machine that moves the upper press die up and down to perform press working with the lower press die, the upper press die attachment method for attaching the upper press die to the press slide while detecting the press load by the load detection means. And (a) a die placement step of placing the upper die of the press at a die placement position of the press machine in a state of being superimposed on the lower die of the press, and (b) detecting the press load by the load detecting means. While lowering the vertical driving member, the press slide is brought into contact with the upper press die to automatically stop the lowering at a position where the press load becomes a predetermined first press load. And lowering step, and having a press upper die mounting step of mounting the pressing upper die on the press slide in a state in which the press slide has been stopped down by the lowering step (c).

[0019]

[Operation and Effect of the Third Invention] That is, the third invention is a method of mounting a press upper die, which comprises the die arranging step, the lowering step, and the press upper die mounting step of the second invention. Compared with the case where the press slide is stopped from being lowered by the switch operation, the burden on the operator is reduced, and there is no fear that an excessive load acts on the press machine to cause damage such as seizure of the drive motor.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an example of a single action type press machine 10 for drawing an outer panel of an automobile, etc., in which a moving bolster 14 to which a punch type 12 is attached is guided by a rail (not shown) provided on a base 16. It is possible to reciprocate between a standby position outside the four frames 17 provided at the four corners of the press machine 10 and a mold disposition position inside the frame 17 shown in the figure, and to dispose the molds. It is designed to be positioned and fixed in the installed position. The press slide 20 to which the die die 18 is attached is connected to four plungers 22, and the vertical drive device 13 disposed on the upper portion of the frame 17 is connected to the press slide 20.
2 (see FIG. 3), the four plungers 22 are vertically driven in synchronization with each other, so that the press slide 2
The zero is moved up and down substantially integrally with the plungers 22. The vertical drive device 132 is configured to include, for example, an electric motor, a gear, a link, a crankshaft, a clutch, a brake, and the like.

The bolster 14 has a cushion pin 2
A large number of through holes 26 are provided for arranging the cushions 4, and a cushion pad 28 for supporting the cushion pins 24 is provided below the bolster 14 which is positioned and fixed at the die disposing position. It is arranged. The cushion pin 24 supports the wrinkle holding ring 30 arranged together with the punch die 12, and the wrinkle holding ring 3
Arbitrary numbers are arranged at predetermined positions which are predetermined according to the shape of 0 and the like. Therefore, the press slide 2
When the die die 18 is lowered together with 0, the peripheral edge of the press material is wrinkled between the die die 18 and the wrinkle retainer ring 30, and drawing is performed between the die die 18 and the punch die 12. Be seen. The die mold 18 corresponds to the upper press mold, the punch mold 12 and the crease presser ring 30 correspond to the lower press mold, and the plunger 22 corresponds to the vertical drive member.

The cushion pad 28 has a large number of hydraulic cylinders 32 corresponding to the through holes 26.
The lower ends of the cushion pins 24 are brought into contact with the pistons of the hydraulic cylinders 32.
The cushion pad 28 can be moved in the vertical direction while being guided by the guide 40, and is always urged upward by the air cylinder 42.
The pressure chamber of the air cylinder 42 is communicated with an air tank 44, and the air tank 44 is an electromagnetic O type.
The ON / OFF supply / exhaust valve 4 is connected to the pressure air source 48 in the factory via the N, OFF supply / exhaust valve 46.
The air pressure Pa in the pressure chamber or in the air tank 44 is adjusted by controlling the switching of 6. The air pressure Pa is detected by the air pressure sensor 50.
Then, when the cushion pad 28 is pushed down via the wrinkle holding ring 30 and the cushion pin 24 during the press working, a wrinkle holding load corresponding to the air pressure Pa is applied to the wrinkle holding ring 30. A plurality of air cylinders 42 are provided as needed, and the pressure chambers of these air cylinders 42 are connected to a common air tank 44. The pressure chambers of the large number of hydraulic cylinders 32 are communicated with each other, and the air-driven hydraulic pump 34 is provided.
The hydraulic pressure Ps in the pressure chamber is adjusted by supplying hydraulic oil from the valve and controlling the opening / closing of the electromagnetic on-off valve 36. The oil pressure Ps is detected by the oil pressure sensor 38. The hydraulic pressure Ps is adjusted such that the wrinkle pressing load acts on the plurality of cushion pins 24 substantially uniformly. A pressure equalizing cushion device 51 is configured by including the cushion pad 28, the hydraulic cylinder 32, and the cushion pin 24.

On the other hand, the plunger 22 is connected to the press slide 20 via a die height adjusting mechanism 52, as shown in FIG. The die height adjusting mechanism 52 corresponds to the height adjusting mechanism, and
Is provided on a screw shaft 54 that is integrally provided with the nut member 56, the nut member 56 is screwed onto the screw shaft 54, the worm wheel 58 is fixed to the nut member 56, and the worm wheel 58 is screwed on the worm wheel 58. And the worm 60 combined. The worms 60 of the die height adjusting mechanism 52 at four positions are rotationally driven in both forward and reverse directions by a common servo motor 134 (see FIG. 3), and accordingly, the worm wheel 58 and the nut member 56 are forward and reverse. It is rotationally driven in both directions, and the height position of the die height adjusting mechanism 52 with respect to the screw shaft 54, that is, the relative distance h ₁ of the press slide 20 with respect to the plunger 22 is uniformly adjusted. As the relative distance h ₁ increases, the press slide 20 is lowered with respect to the plunger 22, and the pressing force when the plunger 22 reaches the lower end, that is, the press load is changed. A strain gauge 61 as a strain sensor is attached to each of the four plungers 22 and outputs a strain signal Sε corresponding to the strain of each plunger 22. These strain gauges 61 include one plunger 22.
Four of them are attached to each other and are connected so as to form a bridge circuit.

The die height adjusting mechanism 52 is a piston 6 of a hydraulic cylinder 62 provided to prevent overload.
4, while the housing of the hydraulic cylinder 62 is integrally arranged on the press slide 20. The pressure chamber of the hydraulic cylinder 62 is filled with hydraulic oil, and the pressure chamber is the oil chamber 6 of the cylinder 66.
It is communicated with 8. The cylinder 66 is provided with an air chamber 70 on the opposite side of the oil chamber 68 with the piston in between. The air chamber 70 is communicated with an air tank 72, and the air tank 72 is of an electromagnetic ON / O type.
It is connected to the pressure air source 48 via the FF supply / exhaust valve 74. By controlling the ON / OFF supply / exhaust valve 74 to be switched, the air pressure Pc in the air chamber 70 and the air tank 72 is adjusted.
c is detected by the air pressure sensor 76. The air pressure Pc allows the piston to retreat toward the air chamber 70 side and the die height adjusting mechanism 52 and the press slide 20 to approach each other when an excessive load is applied to the hydraulic cylinder 62. The pressure is adjusted according to the press capability of the press machine 10 so as to prevent damage to the mold and the like.
The hydraulic cylinder 62, cylinder 66, air tank 72
Etc. are respectively arranged at the connecting portions of the four plungers 22 and the press slide 20, and the air pressure Pc is adjusted individually according to variations in the pressure receiving areas of the hydraulic cylinders 62, 66 at the four locations. Is pressed. The piston may be biased by a compression coil spring or the like instead of the cylinder 66.

The press slide 20 is also connected to a machine frame 78 (see FIG. 1) fixed to the frame 17 via four balancer air cylinders 80. The air chamber of the air cylinder 80 is communicated with an air tank 82, and the air tank 82 is of an electromagnetic ON / O type.
The pressure air source 48 is connected via the FF air supply / exhaust valve 84, and the air pressure Pb in the air chamber or the air tank 82 is adjusted by switching control of the ON / OFF air supply / exhaust valve 84. Has become. This air pressure P
The pressure b is detected by the air pressure sensor 86 and adjusted so as to balance with the weight of the press slide 20 and the die die 18. The air chambers of the four air cylinders 80 are connected to a common air tank 82.

As shown in FIG. 3, the press machine 10 is provided with a controller 90 and a dedicated controller 130. The controller 90 includes the hydraulic pressure sensor 38, the air pressure sensors 50, 76 and 86, and the strain. Oil pressure Ps output from the gauge 61, air pressure Pa, Pc, Pb
And a distortion signal Sε are respectively supplied to the dedicated controller 130, the servo motor 1
A signal representing the relative distance h ₁ is supplied from the rotary encoder 136 attached to the motor 34, and the press stroke Sp of the press machine 10 is supplied from the stroke sensor 138.
Is supplied. The stroke sensor 138 is
For example, the vertical drive device 132 is configured by an encoder or the like that detects the rotation angle of the crankshaft. Controller 9
Each of 0 and 130 is composed of a microcomputer having a CPU, a RAM, a ROM, an input / output interface circuit (not shown), an A / D converter, etc., and exchanges necessary information with each other and temporarily stores the RAM. Using the functions, signal processing is performed in accordance with a program stored in advance in the ROM to switch the ON / OFF supply / exhaust valves 46, 74, 84, the open / close valve 36, the hydraulic pump 34, the vertical drive device 132, and the servo motor 134. The drive signal for changing the operating state of is output. The stroke sensor 138 corresponds to a stroke position detecting means, and the press stroke Sp corresponds to the stroke position of the plunger 22.

The controller 90 also includes a machine information memory 92 and a mold information memory 94. The machine information memory 92 stores machine information specific to the press machine 10 in advance by a keyboard, a personal computer, or the like.
The mold information memory 94 has an ID card 98 attached to the punch mold 12 by a transceiver 96 (see FIG. 1).
The mold information unique to the mold read from is stored. ID
The card 98 is configured to have a storage function for storing mold information, a transmission / reception function, a battery, and the like, and transmits the mold information by receiving a data capture signal from the transceiver 96.

The machine information and the die information are the air pressures Pa, Pb, and
The information necessary for determining the relative distance h ₁ and the like is, for example, as follows. It should be noted that the mold information also includes the type of mold, that is, the type of vehicle, the product number, the press machine used, the process, and the like. (Machine information) -Fp-Sε characteristic-Weight Wa of cushion pad 28-Weight Wp of cushion pin 24-Weight Ws of press slide 20-Pressure receiving area Aa of air cylinder 42-Pressure receiving area of air cylinder 80 (total of four cylinders) ) Ab ・ Overload prevention air pressure Pco (mold information) ・ Weight of wrinkle retainer ring 30 ・ Weight of upper die (die die 18) Wu ・ Wrinkle retainer load Fso ・ Molding load Ffo ・ Number of cushion pins 24 used n・ Thickness t of press material

Here, the Fp-Sε characteristic is the correspondence relationship between the strain signal Sε and the press load Fp as shown in FIG. 4, and for the strain gauges 61 attached to the four plungers 22 at four positions. Each is specified. Figure 4 above
The characteristics of the load measuring device 10 shown in FIG.
0 is used to detect the strain of the plunger 22 with the strain gauge 61 and to measure the actual press load Fp. The load measuring device 100 is a punch type 1
2, the die mold 18, and the wrinkle holding ring 30 are arranged in the press machine 10 to measure the load of each part of the press machine 10, and are box-shaped positioning members 102 fixed on the bolster 14. And its positioning member 1
And a plurality of pins 1 corresponding to the plurality of cushion pins 24 on the lower surface thereof while being housed in the interior of 02 in a vertically movable manner.
04 is provided in a protruding manner, and the load measuring table 106 is provided. The positioning member 102 includes the plurality of cushion pins 24.
A large number of notched holes 108 are formed so that the load measuring table 106 can be provided with the through holes 26 and the notched holes 10.
It is designed to be mounted via a pin 104 on a plurality of cushion pins 24 arranged by inserting 8 through them. Columnar portions 110 are provided at the four corners of the positioning member 102 so as to project upward, and the four corners of the portion of the upper surface of the load measuring table 106 on which the drawing process is generally performed, that is, wrinkle pressing is performed. Four clamped members 112 are fixed to the portion, and the columnar portions 11 of these members are fixed.
0, the clamped member 112 has strain gauges 114,
116 is attached. Also, the plurality of pins 1
The strain gauge 11 also has a position 04 at a predetermined position if necessary.
8 is attached. Then, the strain gauges 114, 1
16 and 118 are connected to a dynamic strain gauge 120 having an amplification function, a zero adjustment function, etc., and an electromagnetic oscilloscope 122.
The load waveform is recorded by. The positioning member 10
2, the load measuring table 106, and the clamped member 112 have rigidity higher than that of a normal mold. Strain gauge 114,11
Four and six 118 are attached around the columnar portion 110, the pinched member 112, and the pin 104, respectively.
They are connected so as to form a bridge circuit. In addition,
The strain gauge 114 is for measuring the outer load (wrinkle pressing load) of the double action type press machine, and the strain gauge 116 is the inner load (forming load) of the double action type press machine or the single action type press machine. Strain gauge 118 for measuring press load
Is for measuring the transmission load of each cushion pin 24 of the pressure equalizing cushion device 51.

When the Fp-Sε characteristic is examined by using the load measuring device 100, the press slide 20 is used.
Air pressure Pb of the air cylinder 80 to balance the weight of
After the pressure is adjusted, the die height adjusting mechanism 52 adjusts the height of the press slide 20 to change the press-in amount and operate the press machine 10, and the press load Fp at the bottom dead center is output signal of the strain gauge 116. And the strain signal Sε of the strain gauge 61 attached to the plunger 22 is detected. FIG. 6 is a diagram showing the measurement results, and FIG. 4 shows the correspondence relationship between the press load Fp and the strain signal Sε based on the data of FIG. As a result, a total of four press loads Fp corresponding to the plunger 22 are located on the front left and right sides and the rear side left and right sides.
Is the strain gauge 6 attached to the four plungers 22.
Based on the 1 distortion signal Sε, each is detected with high accuracy. The strain gauge 61 corresponds to load detecting means. In addition,
The press load of the entire press machine 10 is the total press load Fpt, which is the sum of the press loads Fp at four locations. Further, the press load Fp detected by the strain gauge 61 changes as shown in FIG. 7 in one stroke of the press machine 10, and the wrinkle holding load Fs and the forming load Ff are obtained from this waveform. The wrinkle pressing load Fs is a load applied to the wrinkle pressing ring 30 by the air cylinder 42 via the cushion pin 24, and is a clamping pressure load between the die mold 18 and the wrinkle pressing ring 30, and the forming load Ff is , The clamping load between the die mold 18 and the punch mold 12.

Of the machine information, the weight Wa of the cushion pad 28 is a value obtained by subtracting the sliding resistance and the like. For example, the total wrinkle pressing load F while changing the air pressure Pa.
By measuring st with the load measuring device 100 or the strain gauge 61, st can be obtained from the Fst-Pa characteristic. The weight of the cushion pin 24 is an average value of many cushion pins 24 used in the press machine 10, and the weight Ws of the press slide 20 is, for example, the total press load when the press slide 20 descends while changing the air pressure Pb. By measuring Fpt with the strain gauge 61, it can be obtained from the Fpt-Pb characteristic. Further, the pressure receiving area Aa of the air cylinder 42 is obtained from, for example, the above Fst-Pa characteristic in consideration of air leakage, sliding resistance, etc., and the pressure receiving area (total of four) Ab of the air cylinder 80 is the air leakage or In consideration of sliding resistance and the like, for example, it can be obtained from the Fpt-Pb characteristic. The overload prevention air pressure Pco is a set value of the air pressure Pc of the cylinder 66,
In consideration of the pressure receiving areas of the hydraulic cylinders 62 and 66, the sliding resistance, etc., the air pressures Pc at the four locations are determined in advance by experiments or the like so that the pistons of the cylinders 66 retract with a predetermined overload preventing load. ing.

On the other hand, the weight Wr of the wrinkle retainer ring 30 and the weight Wu of the die die 18 in the die information are actual measured values measured after the wrinkle retainer ring 30 and the die die 18 are manufactured. Load Fso, forming load Ffo
Is obtained by attaching the wrinkle holding ring 30, the die die 18, and the punch die 12 to a trial tri-press for actual press working, and obtaining the load condition by trial and error to obtain an appropriate pressed product. is there. The wrinkle holding load Fso and the forming load Ffo exclude the influence of the weight of the mold and the sliding resistance of each part of the try press,
For example, when a tri-press having the same structure as the press machine 10 shown in FIGS. 1 and 2 is used, the press slide 2
The air pressure Pb is adjusted so that the press slide 20 is lowered by the plunger 22 in a state where 0 and the die die 18 and the lifting force by the air cylinder 80 are balanced, and when the press working is performed in that state, the strain gauge 61 is used. It can be obtained based on the wrinkle pressing load Fs and the forming load Ff which are detected. Wrinkle retainer load Fs in this case
o, the forming load Ffo is a total load obtained by adding the loads at four locations. Also, the number of cushion pins 24 used n
Is determined so that an appropriate pressed product can be obtained according to the shape of the wrinkle press ring 30, and the plate thickness t of the press material is
It is set according to the pressed product to be processed.

A display / operation panel 190 shown in FIGS. 8 to 10 is also connected to the controller 90. The display / operation panel 190 is provided with an operation switch for automatically adjusting the relative distance h _1. Various indicators are provided. The dedicated controller 130 includes a display / operation panel 14
0 and an upper die clamper device 220 are connected to the display / operation panel 140, and an operation switch for operating the vertical drive device 132 at a process speed or inching or stopping it at an arbitrary position, and a relative distance h _1. , A display device for displaying the press stroke Sp and the like are provided.

The upper die clamper device 220 is, for example, as shown in FIG. 11, a clamper rod 224 suspended from a T groove 222 provided in the press slide 20 and the clamper rod 224. Hydraulic cylinder 226 pulling in and driving 224, and clamper rod 22
Air cylinder 2 for reciprocating 4 along T groove 222
28, and the clamper rod 224 is moved by the air cylinder 228 from the standby position shown in (a) to (b).
When the clamper rod 224 is advanced to the clamp position shown in (4), the clamper rod 224 is inserted into the notch 230 formed in the die die 18, and hydraulic oil is supplied to the hydraulic cylinder 226 in this state, so that the housing of the hydraulic cylinder 226 moves. The die die 1 is pressed relatively by the die die 18
8 is fixed to the press slide 20. Air cylinder 22
8 output rods include a connecting member 232 and a block 23.
The proximity switch 236 is connected to the clamper rod 224 via the switch 4, and the housing of the hydraulic cylinder 226 detects that the clamper rod 224 has reached the clamp position. The output signal of the proximity switch 236 is supplied to the dedicated controller 130, and a switching valve arranged in an air circuit that supplies pressurized air to the air cylinder 228 or a hydraulic circuit that supplies hydraulic oil to the hydraulic cylinder 226. Is a dedicated controller 1
The die type 18 is switched by 30
Clamping and unclamping are performed automatically.

Next, the attachment of the die 18 and the adjustment of the relative distance h ₁ , the air pressure Pa, etc., which are carried out at the time of die replacement will be described with reference to the flow charts of FIGS. 12 and 13. This flowchart shows a switch operation by an operator and the operation by the controllers 90 and 130.

In step Q1 of FIG. 12, the punch type 12 is operated by operating a switch provided on the display / operation panel 140.
A bolster 14 on which the wrinkle holding ring 30 and the die die 18 are mounted while the punch die 12 is fixed.
Is moved into the press machine 10, and in step Q2, the bolster 14 is positioned at the die placement position. The movement and positioning of the bolster 14 are automatically performed by operating a movement positioning device (not shown) according to a drive signal output from the dedicated controller 130. After that, in step Q3, the operator operates the changeover switch 192 of the display / operation panel 190 to the "individual" mode, and in step Q4, when the operator operates the changeover switch 194 to the "setup" mode, the setup lamp 196 turns on. Light. After the operator presses the operation preparation push button 198 in step Q5, when the operator turns on the trial hit switch of the display / operation panel 140 in step Q6, the press machine 10 is operated by inching. At this time, the air pressure Pb of the air cylinder 80 is Pb≈Ws / Ab based on the weight Ws of the press slide 20 and the pressure receiving area Ab of the air cylinder 80 stored in the machine information memory 92. The pressure is adjusted in advance by switching the ON / OFF air supply / exhaust valve 84, and the air pressures Pc of the four cylinders 66 are made to substantially match the overload prevention air pressure Pco also stored in the machine information memory 92. To
The pressure is adjusted in advance by switching the ON / OFF supply / exhaust valve 74. The adjustment of the air pressures Pb and Pc is performed by displaying the value of Ws / Ab and the air pressure Pco on the display so that the operator can switch the manual valve or the like while observing the air pressure meter. You can

In the next step Q7, the strain signals S of the strain gauges 61 at the four points are lowered in the descending process of the press slide 20.
It is determined whether or not the total press load Fpt calculated based on ε has reached a preset set load F ₀ , and Fpt
= F ₀ , the descending of the press slide 20 is automatically stopped in step Q8. The set load F ₀ is preset to a value of, for example, several tons to tens of tons so as not to overload the electric motor or the like of the press machine 10. The reason why the press slide 20 is automatically stopped from falling when Fpt = F ₀ is that the “setup” mode is selected. In the subsequent step Q9, the die die 18 is fixed to the press slide 20. This die die 18 is automatically attached by the upper die clamper device 220 when an operator operates a switch provided on the display / operation panel 140, but the operator manually uses a T-bolt or the like. It may be done. In addition, step Q10
Then, the press stroke Sp at this stop is stored as the stroke Sp1, and in step Q11, the reverse slide switch of the display / operation panel 140 is operated to raise the press slide 20 in reverse. In step Q12, it is detected by the stroke sensor 138 that the press slide 20 has reached the top dead center, and the top dead center lamp 200 of the display / operation panel 190 is turned on, so that the operator can operate the display / operation panel 140. The press machine 10 is stopped by operating the switch. These steps Q11 and Q12 may be automatically performed.

Next, in step Q13, when the operator operates the changeover switch 194 to the "try" mode, the try lamp 202 is turned on. In step Q14, the distance ΔSp from the stop position at the time of mold attachment to the bottom dead center is calculated based on the stroke Sp1 and the distance Δ is determined.
Sp, the plate thickness t of the press material stored in the die information memory 94, and the predetermined additional driving amount x ₀ , the change amount Δh of the relative distance h ₁ is calculated according to the following equation (1), and the servo motor By driving 134, the relative distance h ₁ is automatically changed by the change amount Δh. By reducing the distance ΔSp to the bottom dead center, the total press load Fpt when the press slide 20 is lowered to the bottom dead center becomes the set load F ₀ , and by further reducing the plate thickness t, the press material is reduced. The total press load at the bottom dead center when is input is Fpt = F ₀ . That is, if the relative distance h ₁ is changed by the change amount Δh, the press-in amount when the press material is introduced and the press slide 20 is lowered to the bottom dead center is substantially increased by the additional drive-in amount x ₀ . is there. The additional driving amount x ₀ is, for example, 1.0 mm
The value of degree is set. Note that steps Q1 and Q2
When the pre-pressed press product is interposed between the punch die 12 and the die die 18 at the time of loading the die, it is not necessary to subtract the plate thickness t.

[Formula 1] Δh = −ΔSp−t + x ₀ (1)

Here, for the mold information such as the plate thickness t, after the step Q2, the ID communication switch 204 of the display / operation panel 190 is operated to the "ON" side, and the read push button 20.
When 6 is pressed, it is read from the ID card 98, stored in the mold information memory 94, and part of it is displayed on the display unit 208 of the display / operation panel 190. The display unit 208 is provided with a display 210 for displaying the molding load Ffo, a display 212 for displaying the weight Wu of the upper die (die die 18), and the like.

In step Q15, the press material is put in,
In step Q16, the operator turns on the trial hit switch of the display / operation panel 140 to operate the press machine 10 for one cycle. At this time, the air pressure Pb of the air cylinder 80
Is based on the weight Ws of the press slide 20 and the pressure receiving area Ab of the air cylinder 80 stored in the machine information memory 92, and the weight Wu of the die die 18 stored in the die information memory 94. ≒ (Ws + W
u) / Ab ON / OFF supply / exhaust valve 8
The pressure has been adjusted in advance by switching 4 above. Step Q17
Then, the total press load Fpt at the bottom dead center during the press operation is detected based on the strain signal Sε of the strain gauge 61, and the total press load Fpt is stored as F ₁ .

In step Q18 of FIG. 13, which is subsequently executed, the load change rate Δa is calculated from the load values F ₀ and F ₁ and the additional drive amount x _{0 according} to the following equation (2). 14
Is a graph showing the relationship between the load values F ₀ and F ₁ and the press-in amount, and the load change rate Δa corresponds to the slope of this graph, which is a characteristic peculiar to the press machine 10. If the actual total press load Fpt when the slide is stopped in step Q8 does not match the set load F ₀ due to the operation delay of the vertical drive device 132, etc., the actual total press load Fpt at that time is stored. In calculating the change rate Δa, it is desirable to use the load value Fpt. In addition, the press drive-amount, the relative distance h ₁ when the die 18 is just in contact with the punch die 12 as a reference value h ₀ in the press bottom dead center, increasing the relative distance h ₁ from the reference value h ₀ A large amount (h ₁ −h ₀ ),
As the amount of press-in increases, each part of the press machine 10 elastically deforms or the hydraulic oil in the hydraulic cylinder 62 compressively deforms, generating a press load.

[Formula 2] Δa = (F ₁ −F ₀ ) / x ₀ (2)

In the next step Q19, the load change rate is calculated.
Δa, molding load stored in the mold information memory 94
Ffo, the load value F₁Based on the relative distance h₁Change of
Quantity x ₁Is calculated according to the following equation (3) and the servo
Driving the motor 134 to change the amount x₁Only relative distance h
₁Is automatically changed. Thus the relative distance h₁Is the change amount
x₁It is clear from Fig. 14 that only the changes are made.
Basically, the total press load Fpt at bottom dead center is
The forming load becomes Ffo. At this stage,
Bias the wrinkle retainer ring 30 via the pin 24
The air cylinder 42 for holding the wrinkle is locked at the lower end.
With the press slide 20 lowered to bottom dead center
Also, the die die 18 comes into contact with the wrinkle retainer ring 30.
No wrinkle holding load is 0. Also, the above
Substituting the load change rate Δa in equation (2) into equation (3)
Therefore, the load value F₀, F₁, Forming load Ffo, additional addition
Quantity x₀Change amount x₁Can also be calculated directly.

[Mathematical formula-see original document] x ₁ = (Ffot −F ₁ ) / Δa (3)

At step Q20, the operator turns on the trial hit switch to operate the press machine 10 for only one cycle, and at step Q21, the total press load Fpt at the bottom dead center during press operation is calculated by the strain gauge 61 strain. It is detected based on the signal Sε and it is determined whether or not the difference | Fpt−Ffot | between the total press load Fpt and the forming load Ffo is smaller than a predetermined error allowable range α. The allowable error range α is, for example, when the forming load Ffo is 80 kN.
In the case of (kilonewton), it is set to about 1.0 kN. Then, if | Fpt−Ffot | ≧ α, | Fpt
-Ffot | <α until the relative distance h is reached in step Q22.
Correct ₁ . The correction of the relative distance h ₁ may be automatically performed by linearly approximating the load change with respect to the press-in amount as in steps Q18 and Q19, but it is displayed on the display 214 of the display / operation panel 190. The operator sees the value of the actual total press load Fpt
Compared with the forming load Ffo displayed at 0, servo motor 1
It is also possible to operate the switch 34 by operating a switch.

If the judgment in step Q21 is YES, the total load lamp 216 of the display / operation panel 190 is turned on, and then step Q23 and the subsequent steps are executed. In step Q23, the press slide 20 is lowered by operating the switch of the display / operation panel 140, and in step Q24, the press slide 20 is stopped at the bottom dead center by operating the switch of the display / operation panel 140. At step Q25, the lock of the air cylinder 42 is released to raise the cushion pad 28, and then step Q25
26, the weight Wa of the cushion pad 28 and the weight W of the cushion pin 24 stored in the machine information memory 92.
p, the pressure receiving area Aa of the air cylinder 42, the wrinkle pressing load Fso stored in the mold information memory 94, the weight Wr of the wrinkle pressing ring 30, the number of cushion pins 24 used n
Based on the above, the air pressure Pax for obtaining the wrinkle pressing load Fso is calculated according to the following equation (4), and the ON / OFF supply / exhaust valve 46 is controlled to be switched so that the air pressure Pa≈Pax. The weight Wr of the wrinkle holding ring 30 is generally less than 10 tons in the press working of the outer panel of the automobile, which is smaller than the other members, and the air pressure Pa may be adjusted by ignoring this.

## EQU00004 ## Pax = (Fso + Wa + Wr + n.Wp) / Aa (4)

By adjusting the air pressure Pa in step Q26, the total press load Fpt detected by the strain gauge 61 increases by the wrinkle pressing load Fso, and in the next step Q27, the wrinkle pressing load Fso and the forming load. Total load Fpo that adds Ffo and total press load Fpt
And the difference | Fpt-Fpo |
Determine if less than. And | Fpt-Fpo |
If ≧ β, the air pressure Pa is automatically adjusted in step Q26 until | Fpt−Fpo | <β, and | Fpt−Fpo | <
When β is reached, the normal lamp 218 regarding the press load is turned on in step Q28. The readjustment of the air pressure Pa in step Q26 is performed so that the air pressure Pa is reduced if the difference (Fpt−Fpo) is positive and is increased if the difference (Fpt−Fpo) is negative. The air pressure Pa may be increased until | Fpt−Fpo | <β is satisfied without calculating the air pressure Pax according to the above equation (4).

Here, the press machine 10 according to the present embodiment.
Are load values F ₀ , F _{1 at} two points with different press-in amounts,
Based on the additional drive-in amount x ₀ , the load change characteristic peculiar to the press machine 10 shown in FIG. 14, that is, the correlation between the total press load Fpt and the press-up amount is obtained by linear approximation, and the forming load Ffo is calculated according to the load change characteristic. since is adapted to adjust the relative distance h ₁ so as to obtain, can adjust the relative distance h ₁ with a small test shot count, along with the burden on the operator is greatly alleviated, adjustment time can be shortened by pressing The operating rate of the machine 10 is improved. In particular, since the above load change characteristics are obtained by using the load value F ₀ when attaching the die 18 to the press slide 20 during die replacement, the time required for die replacement including adjustment of the relative distance h ₁ is further shortened. There are advantages.

Also, the die slide 18 is attached to the press slide 20.
When the press slide 20 is moved down to attach the press slide 20, the press slide 20 is automatically stopped at the position where the total press load Fpt becomes a predetermined set load F ₀ (step Q8). Compared with the case where the descent is stopped by the switch operation, the burden on the operator is reduced, and an excessive load may be applied to the press machine 10 to cause damage such as seizure of the drive motor of the vertical drive device 132. Absent.

Further, in this embodiment, since the relative distance h ₁ is automatically adjusted by the switch operation of the operator, there is no fear that the relative distance h ₁ is erroneously adjusted due to the operator's calculation error or adjustment error. The burden on the operator is further reduced. In this embodiment, the trial hit switch is operated to operate the press machine 10. However, when a safety fence or the like is provided, the relative distance h ₁ including the operation of the press machine 10 The adjustment can be fully automated, or conversely, the relative distance h ₁ can be changed by an operator's switch operation.

In this embodiment, the steps Q1 and Q2 are the die placing step, the steps Q6 to Q8 are the lowering step, the step Q9 is the upper press attaching step, the step Q11 is the raising step, and the step Q14 is the first step. In the first height changing step, steps Q16 and Q17 are the second press load detecting step, and steps Q18 and Q19 are the second height changing step. The forming load Ffo corresponds to the target pressing load, the set load F ₀ corresponds to the first pressing load, the additional driving amount x ₀ corresponds to the first driving changing amount, and the load value F ₁ is the second pressing load. The change amount x ₁ corresponds to the second additional change amount.

In the above example, step Q7 in FIG.
It is determined whether or not the total press load Fpt matches the set load F _0, and the descending of the press machine 10 is automatically stopped at the position of Fpt = F _0. However, as shown in FIG. Q7 may be omitted, and the operator may visually confirm that the press slide 20 has come into contact with the die die 18, and stop lowering of the press machine 10 by operating a switch. In that case, in step Q10, the press stroke Sp when the descent is stopped is stored as the stroke Sp1, and the total press load Fpt is the load F _0.
And the stroke value Sp1 and the load value F ₀
It suffices to perform the subsequent processing by using.

Further, in the above-mentioned embodiment, a constant value is set in advance as the additional drive-in amount x ₀ , but the molds 12, 18,
By arranging the load measuring device 100 or the like having a rigidity higher than that of 30 and measuring the total press load Fpt while changing the relative distance h ₁ , for example, FIG.
If a temporary load change characteristic A as indicated by the solid line, that is, the correlation between the total press load Fpt and the press-in amount is previously obtained and stored as machine information in the machine information memory 92, the press machine The additional drive-in amount x ₀ can be increased within a range in which 10 is not overloaded. That is, based on the load value F ₀ and the load change characteristic A, the additional drive-in amount x ₀ for obtaining the molding load Ffo is obtained, and the change amount Δh is calculated according to the equation (1) using the additional drive-in amount x _0. It is calculated. 16B is an actual load change characteristic, which corresponds to the load change characteristic of FIG. 14, but the provisional load change characteristic A is obtained by interposing a member having higher rigidity than the mold. The actual load change characteristic B has a gentler inclination than the tentative load change characteristic A, and even if the press drive amount is changed by the additional drive amount x ₀ obtained based on the tentative load change characteristic A, the press machine 10 can It is not overloaded. Also, the target forming load F
Since the load change characteristic B, in other words, the load change ratio Δa is obtained by using the load value F ₁ close to fo, there is less error than the load change characteristic of FIG.
The correction of the relative distance h ₁ at 22 is unnecessary or reduced. It should be noted that, if the load change characteristic is A, the additional drive-in amount for obtaining the forming load Ffo is x ₀ , but it is not always necessary to set the additional drive-in amount x ₀ based on the forming load Ffo, and a load smaller than that may be used. Of course, the additional drive-in amount x ₀ can be set based on a load slightly larger than the forming load Ffo.

In the above embodiment, the single action type press machine 10 has been described. For example, referring to FIG.
The present invention can be applied to a double action type press machine 150 as shown in FIG. In FIG. 17, the die type 1
52 is fixedly used on the moving bolster 154, while the wrinkle pressing ring 156 is fixedly mounted on the outer slide 160 via the blank holder plate 158,
The punch mold 162 is fixedly used on the inner slide 164. The outer slide 160 can be vertically moved via four outer plungers 166, and the inner slide 164 can be vertically moved via four inner plungers 168. While pressing the peripheral edge of the press material between 156 and the wrinkle holding portion 153 of the die die 152, drawing is performed by the punch die 162 and the die die 152. Outer slide 160, inner slide 1
64 corresponds to a press slide, and the outer plunger 16
6, the inner plunger 168 corresponds to the vertical drive member,
The wrinkle holding ring 156 and the punch die 162 correspond to the upper press die, and the die die 152 corresponds to the lower press die.

As is apparent from FIG. 18, the four outer plungers 166 are the die height adjusting mechanism 2 respectively.
It is connected to the outer slide 160 via 40.
The die height adjusting mechanism 240 is configured in the same manner as the die height adjusting mechanism 52, and the relative distance h ₂ is uniformly adjusted by the worm 242 being rotationally driven in both forward and reverse directions by a common servo motor, and the outer plunger 166. The pressing load Fp when is reached to the lower end is changed. Each outer plunger 166 has a strain gauge 2
46 is attached, and based on the strain of each outer plunger 166, the press load Fp,
In this case, the wrinkle holding load is detected.

The die height adjusting mechanism 240 is integrally connected to the piston 250 of the hydraulic cylinder 248, while the housing of the hydraulic cylinder 248 is integrally provided on the outer slide 160. Hydraulic cylinder 2
The pressure chamber of 48 is filled with hydraulic oil,
It communicates with the oil chamber 254 of the cylinder 252. The cylinder 252 is provided with an air chamber 256 on the opposite side of the oil chamber 254 with the piston in between. The air chamber 256 is communicated with an air tank 258, and the air tank 258 is an electromagnetic ON / OFF supply / exhaust valve. It is connected to the pressure air source 262 via 260. ON, OF
By controlling the switching of the F air supply / exhaust valve 260, the air pressure Pe in the air chamber 256 and the air tank 258 is adjusted, and the air pressure Pe is measured by the air pressure sensor 264.
Detected by. The cylinder 252, the air tank 258, etc. are arranged at the connecting portions of the four outer plungers 166 and the outer slide 160, respectively.
The air pressure Pe at each location is adjusted independently. In addition,
The air pressure Pe in this case is adjusted according to the wrinkle pressing load in a range lower than the air pressure for preventing overload.

The outer slide 160 is also connected to the pistons of the four balancer air cylinders 266, and the air chambers of the air cylinders 266 have an air tank 26.
8 and the air tank 26
Reference numeral 8 is connected to the pressure air source 262 via an electromagnetic ON / OFF supply / exhaust valve 270. ON, OFF
By controlling the supply / exhaust valve 270 to be switched, the air pressure Pd in the air chamber of the air cylinder 266 and the air tank 268 is adjusted, and the air pressure Pd is detected by the air pressure sensor 272. . The air pressure Pd is adjusted so as to balance with the weights of the outer slide 160, the blank holder plate 158, and the wrinkle holding ring 156. The four air cylinders 26
The six air chambers are connected to a common air tank 268.

Also in such a press machine 150, the total wrinkle holding load Fso is set by an ID card or the like, and the total press load Fp which is the total of the press load Fp detected by the strain gauge 246.
The relative distance h ₂ is adjusted so that pt becomes the wrinkle pressing load Fso. As shown in FIG. 19, the load change characteristic of the total press load Fpt with respect to the press-in amount is refracted by the load Fct, and the portions below the load Fct are elastically deformed and the operation of the hydraulic cylinder 248 in the same manner as in the above embodiment. It is based on the compressive deformation of oil, and the part above the load Fct is the cylinder 252.
The reciprocating point load Fct is determined by the air pressure Pe and the pressure receiving area on the air chamber 256 side. Therefore, if the pressure receiving areas of the four cylinders 252 on the air chamber 256 side are stored in advance as machine information, the bending point load Fct can be obtained based on the air pressure Pe adjusted according to the wrinkle pressing load Fso. , Fig. 2
By setting a load, which is slightly larger than the inflection point load Fct, such as 0, as the set load F ₀ , the relative distance h ₂ can be adjusted so that Fpt≈Fso as in the above-described embodiment. 20A corresponds to FIG. 14 in the case where a constant value is previously set as the additional drive amount x ₀ , and FIG. 20B is added from the temporary load change characteristic A stored in advance as machine information. The case where the drive-in amount x ₀ is set corresponds to FIG. In this embodiment, the wrinkle holding load F
so corresponds to the target press load.

In addition, the four inner plungers 168 are provided.
Is connected to the inner slide 164 in the same manner as the outer plunger 166, the press load is detected by the strain gauge, and the press load substantially matches the molding load preset on the ID card or the like. The relative distance is adjusted in the same manner as in the first embodiment.

Although some embodiments of the present invention have been described in detail with reference to the drawings, the present invention can be carried out in still another mode.

For example, in the above embodiment, the strain gauges 61 and 246 are attached to the four plungers 22 and 166 to detect the total press load Fpt, but the strain sensor is attached to the frame 17 or the like to perform the pressing. The position and number of the press load to be detected can be appropriately changed such that the load can be detected.

In the first embodiment, the wrinkle pressing air cylinder 42 is locked at the descending end, and the press slide 2
The case where the relative distance h ₁ is adjusted in the state where 0 is lowered to the bottom dead center and the wrinkle pressing load is not applied has been described, but the air pressure Pa of the air cylinder 42 is adjusted so that a predetermined wrinkle pressing load is obtained. After adjustment, the total press load Fpt is the target press load, that is, the forming load F.
The relative distance h ₁ may be adjusted so that the total load Fpo is the sum of fo and the wrinkle holding load Fso.

In the above embodiment, the relative distances h ₁ and h ₂ of the four die height adjusting mechanisms 52 and 240 are uniformly adjusted by the common servo motors. It is also possible to independently arrange servomotors in the mechanisms 52 and 240 so that the relative distances h ₁ and h ₂ at four locations can be adjusted individually. In that case, the forming load and the wrinkle pressing load at four locations can be individually set and adjusted extremely finely.

In the embodiment shown in FIG. 17, the total press load Fpt on the outer side is set in the load range equal to or greater than the inflection point load Fct, in other words, in the load region in which the piston of the cylinder 252 retracts. The total press load Fpt may be set within the load range of the bending point load Fct or less.

On the contrary, in the first embodiment, the cylinder 66
Total press load F in the load area where the piston of
It is also possible to set pt, and in that case, the relative distance h ₁ may be adjusted in the same manner as the setting of the outer side press load Fpt in the embodiment of FIG. The same applies to the inner side press load of the embodiment of FIG.

Further, although the strain gauges 61 and 246 are used to detect the press load in the above embodiment, various other strain sensors can be adopted, and the hydraulic cylinder 62,
It is also possible to detect the press load from a predetermined data map or the like based on the oil pressure 248 and the air pressures Pc and Pe. When there is almost no difference between the load value detected by the strain gauge and the actual press load, it is not always necessary to perform load measurement and correction as in the above-described embodiment, and the load detected by the strain gauge is not necessary. The value can be used as it is.

In the above embodiment, the total press load Fpt is calculated from the relationship between the press load Fp at four locations and the strain signal Sε.
It was designed to calculate the strain gauge 61 at four locations,
246 total detected load value and total press load F
It is also possible to set the correlation data with pt and directly obtain the total press load Fpt.

Further, in the above-mentioned embodiment, the load change characteristic is obtained by using the load value F ₀ at the time of exchanging the die, but after the die is exchanged, that is, in the first embodiment, the press slide is carried out. After attaching the die mold 18 to 20, the relative distance h ₁ may be adjusted by performing a trial hit.

Although the mold information is stored in the ID card 98 in the above-described embodiment, when the number of molds used is small, the computer on the press machine side stores the mold type. The mold information may be stored in association with each other. Other storage means such as a floppy disk or a magnetic tape can be used, or an operator may input and set by key input.

Further, in the above-described embodiment, the case where the present invention is applied to the press machines 10 and 150 for drawing is described. However, the drawing press machine without the pressure equalizing cushion device 51, the one for bending, etc. The present invention can be similarly applied to various other press machines.

Although not illustrated one by one, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a configuration diagram illustrating an example of a single action type press machine capable of suitably implementing the method of the present invention.

FIG. 2 is a diagram illustrating a configuration of a connecting portion between a plunger and a press slide of the press machine in FIG.

FIG. 3 is a block diagram illustrating a control system of the press machine of FIG.

4 is an example of a data map showing a correlation between a press load Fp and a strain gauge output signal Sε stored in the machine information memory of FIG.

5 is a view showing a state in which a load measuring device is arranged to measure an actual press load in the press machine of FIG.

6 is a diagram showing the results of measuring the strain gauge output signal Sε and the press load Fp while changing the press-in amount in the case of FIG. 5, and is the basic data of the data map of FIG. 4.

FIG. 7 is a diagram illustrating a relationship between a fluctuation waveform of a press load Fp, a wrinkle holding load Fs, and a forming load Fs in the press machine of FIG. 1.

8 is a display / operation panel 190 of FIG. 3 together with FIG. 9 and FIG.
FIG.

9 is a diagram showing a display / operation panel 190 together with FIGS. 8 and 10. FIG.

10 is a view showing a display / operation panel 190 together with FIGS. 8 and 9. FIG.

11 is a cross-sectional view showing the upper clamper device of FIG.
(A) shows an unclamped state, and (b) shows a clamped state.

FIG. 12 is a flowchart illustrating a procedure for adjusting the relative distance h ₁ according to a preset molding load in the press machine of FIG. 1.

FIG. 13 is a view showing a continuation of the flowchart of FIG.

FIG. 14 is a diagram illustrating a method of adjusting the relative distance h ₁ so that the total press load Fpt and the forming load Ffo are substantially the same according to FIGS. 12 and 13.

15 is a diagram illustrating another embodiment of the present invention, and FIG.
Is a flowchart used instead of

FIG. 16 is a diagram illustrating another method of adjusting the relative distance h ₁ so that the total pressing load Fpt and the forming load Ffo substantially match.

FIG. 17 is an overall configuration diagram illustrating an example of a double action type press machine capable of suitably implementing the method of the present invention.

18 is a diagram illustrating a configuration of a connecting portion between the outer plunger and the outer slide of the press machine of FIG.

19 is a diagram showing a change characteristic of the total press load Fpt on the outer side with respect to the press-in amount in the press machine of FIG.

FIG. 20 is a view for explaining the operation when adjusting the relative distance h ₂ so that the total press load Fpt on the outer side substantially matches the crease presser load Fso in the press machine of FIG. 17, (a) of FIG. 14 and FIG. 16B corresponds to FIG.

[Explanation of symbols]

10: Press machine 12: Punch type (press lower die) 18: Die type (upper die) 20: Press slide 22: Plunger (upper and lower driving member) 30: Wrinkle retainer ring (press lower die) 52: Die height adjusting mechanism ( Height adjusting mechanism) 61: Strain gauge (load detecting means) 138: Stroke sensor (stroke position detecting means) 150: Press machine 152: Die type (press lower die) 156: Wrinkle holding ring (press upper die) 160: Outer Slide (press slide) 162: Punch type (press upper die) 164: Inner slide (press slide) 240: Die height adjusting mechanism (height adjusting mechanism) 246: Strain gauge (load detecting means) Fpt: Press load Ffo: Forming load (Target press load) F ₀ : 1st press load F ₁ : 2nd press load x ₀ : 1st insertion change Amount x ₁ : Second amount of change for insertion Fso: Wrinkle holding load (target press load) Steps Q1, Q2: Mold placement process Steps Q6, Q7, Q8: Lowering process Step Q9: Press upper die mounting process Step Q11: Ascending process Step Q14: First height changing step Steps Q16, Q17: Second press load detecting step Steps Q18, Q19: Second height changing step

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B30B 15/28 A 8718-4E

Claims (3)

[Claims] 1. A press slide, which is connected to an up-and-down driving member to be moved up and down, and whose height is adjusted by a height adjusting mechanism provided at a connecting portion with the up-and-down driving member. In a press machine in which the upper press die attached to the upper and lower parts is moved up and down to perform press working with the lower press die, the press load is detected by the load detection means and the stroke position of the vertical drive member is detected by the stroke position detection means. A method of adjusting the height of the press slide by the height adjusting mechanism so as to obtain a predetermined target press load while detecting, and a position at which a predetermined press load is generated while lowering the vertical drive member. And a lowering step of raising the vertical driving member to separate the upper press die from the lower press die. And the press load when the press slide is stopped to descend in the descending process as a first press load, and the vertical drive member bottoms out based on the stroke position of the vertical drive member when the descending stop is performed. A height change amount by which the first press load is obtained when the press slide is lowered to a point position is obtained, and the height of the press slide is changed by a dimension obtained by adding a predetermined first drive change amount to the height change amount. A first height changing step, and a second press load detecting step of driving the vertical drive member while changing the height of the press slide to detect a press load at a bottom dead center position as a second press load, On the basis of the first press load, the second press load, and the first change amount of press-in, a correlation between the press-in amount of the press slide and the press load is obtained by linear approximation, and the correlation is calculated from the correlation. And a second height changing step of changing the height of the press slide by the second amount of change in driving to obtain a target press load, and a second height changing step. Height adjustment method. 2. A press slide which is connected to an up-and-down driving member to move up and down and whose height is adjusted by a height adjusting mechanism provided at a connecting portion with the up-and-down driving member. In a press machine in which the upper press die attached to the upper and lower parts is moved up and down to perform press working with the lower press die, the press load is detected by the load detection means and the stroke position of the vertical drive member is detected by the stroke position detection means. A method of adjusting the height of the press slide by the height adjusting mechanism so as to obtain a predetermined target press load while detecting, wherein the press upper die is pressed at a die placement position of a press machine. A die placing step of placing the die in a state of being superposed on the die; A descending step of automatically stopping the descending at a position where the press slide comes into contact with the press upper die and the press load becomes a predetermined first press load, and the press slide is stopped to descend in the descending step. A press upper die attaching step of attaching the press upper die to the press slide in a state; a raising step of raising the vertical drive member to separate the press upper die attached to the press slide from the press lower die, Based on the stroke position of the vertical drive member when the press slide is stopped to descend in the descending step,
The height change amount by which the first press load is obtained when the vertical drive member is lowered to the bottom dead center position is obtained, and the press amount is increased by a size obtained by adding a predetermined first drive change amount to the height change amount. A first height changing step of changing the height of the slide; and a step of driving the vertical drive member while changing the height of the press slide to detect a press load at a bottom dead center position as a second press load. 2 Press load detection step, and based on the first press load, the second press load, and the first close-in change amount, the correlation between the close-in amount of the press slide and the press load is obtained by linear approximation, and the correlation is obtained. And a second height changing step of changing the second slide changing amount by which the target press load is obtained and changing the height of the press slide by the second close changing amount. Slide height adjustment method of 械. 3. A press machine comprising a press slide connected to an up-and-down driving member to be moved up and down, and an upper press die attached to the press slide is moved up and down to perform press working with a lower press die. A method of mounting the upper press die on the press slide while detecting a press load by a load detection means, wherein the upper press die is superposed on the lower press die at a die placement position of a press machine. A die arranging step in which the press load is detected by the load detecting means, the vertical driving member is lowered, the press slide contacts the upper press die, and the press load is predetermined. 1 The descending step of automatically stopping the descending at the position where the press load is applied, and the press slide in the state where the press slide is stopped descending in the descending step. Press upper die mounting method of a press machine, characterized in that the upper die and a press upper mold attaching step of attaching to the press slide.