JP2007136555A - Press machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press machine where an overload and a light load are detected and a press is stopped as the protection of a die is secured. <P>SOLUTION: A slide is made vertically moved by motor rotation control in accordance with the number of selected position command pulses, an overload prevention apparatus is provided between a crankshaft and the slide, in the case the fact that calculated slide pressurizing force exceeds the excessive side value in a memory set drivable pressurizing force range is judged, a horupu (phonetic) pressure fracture command signal and a press stop command signal can be created and output, and, in the case the fact that calculated slide pressurizing force is less than the lower side in the memory set drivable pressurizing force is judged, a press stop command signal can be created and output. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a press machine that presses a slide while raising and lowering a slide while controlling the rotation of a slide drive motor connected to a crankshaft.

  In a conventional press machine in which the drive mechanism is a crank mechanism and includes a flywheel and a clutch / brake device, a large slide pressure (load value) can be obtained, but slide motion [time-slide position (or crank angle- Slide position)] curve has a sine wave shape, so that it is not possible to adopt a slide motion curve similar to the case of other drive mechanisms (for example, knuckle mechanism, link mechanism, etc.). Even when the drive mechanism is, for example, a toggle mechanism (or a link mechanism), a slide motion curve similar to the case of other drive mechanisms (for example, a crank mechanism) cannot be taken.

  Therefore, the applicant has proposed a so-called servo motor driven press machine that drives the crankshaft with a motor while taking advantage of the crank mechanism (large load value generation, simple structure, robustness, low cost, etc.) (patent) Reference 1).

  According to such a press machine, since various slide motions can be switched, the adaptability to the press working mode can be expanded and the flywheel, the clutch / brake device can be eliminated as compared with the case of the conventional example. Therefore, it is advantageous in terms of equipment economy and reduction in size and weight. The problem of shortening the life due to the frequent operation of the clutch / brake device is eliminated.

  By the way, in the conventional press machine configured to selectively transmit / separate the rotational energy accumulated in the flywheel to the crankshaft via the clutch and brake to perform the press operation / stop, the upper die is pressed before the press operation. Die height setting work is performed by adjusting the vertical position or the vertical position of the lower die. The bottom dead center position of the slide at this time is determined by the crank mechanism (crankshaft). Therefore, even if each component (eg, connecting rod, frame) expands and contracts due to heat generation during the press operation, the bottom dead center position (that is, die height) necessary to cancel it cannot be adjusted. .

That is, the bottom dead center position (die height) adjustment is performed by manually or electrically adjusting and driving a die height position adjusting device mounted on the bolster (lower die) side after the press operation is stopped.
JP 2003-260598 A

  Here, even in the previously proposed press machine (electric crank press), as in the case of the conventional press machine, the bottom dead center position is caused by the expansion and contraction of each component (eg, connecting rod, frame) due to heat generation during the press operation. (That is, die height) cannot be denied. From this point, of course, mold protection is important. In addition, there is a strong demand for automatically detecting light loads caused by punch breakage.

  An object of the present invention is to provide a press machine capable of detecting both an overload and a light load and stopping the press while ensuring mold protection.

  According to the first aspect of the present invention, a slide drive motor is directly or indirectly connected to the crankshaft via a gear, and the slide drive motor is rotated in accordance with the number of selected position command pulses output according to the slide motion at each selection cycle. The slide is configured to be able to move up and down while being controlled, and an overload prevention device is provided between the crankshaft and the slide. The pressurizing range pattern data in which the angle and the set operation possible pressurizing range are associated with each other can be stored, and the detected crank angle is supported using an arithmetic expression including the detected motor current and the detected crank angle. The slide pressure can be calculated, and the calculated slide pressure corresponds to the detected crank angle. Is generated so that a holp pressure breaking command signal and a press stop command signal can be generated and output, and the calculated slide pressurizing force corresponds to the detected crank angle. The press machine is configured to generate and output a press stop command signal when it is determined that the press stop command signal is less than

  In the press machine according to the first aspect of the present invention, the overload prevention device enters the press operation with the holp pressure established state capable of transmitting the applied pressure. That is, the slide is moved (lifted / lowered) while the rotation of the slide drive motor is controlled according to the number of selected position command pulses output according to the slide motion for each selection cycle. During this period, the crank angle is detected, and a slide pressure corresponding to the detected crank angle is calculated using an arithmetic expression. When it is determined that the calculated slide pressing force exceeds the excessive value in the memory setting operable pressure range corresponding to the detected crank angle, a holp pressure breaking command signal and a press stop command signal are generated and output. That is, in the case of occurrence of overload, the overload prevention device is put into a horup pressure rupture state and the press is forcibly stopped.

  On the other hand, if the calculated slide pressure is less than the underside value of the memory setting operable pressure range corresponding to the detected crank angle, that is, a light load occurs, a press stop command signal is generated and output to forcibly stop the press. . The overload prevention device remains in the state of establishing a holp pressure capable of transmitting the applied pressure.

  Therefore, it is possible to stop the press by detecting both overload and light load while ensuring mold protection. That is, the mold protection can be perfected in the case of an overload, the punch can be exchanged quickly in the case of a light load, and the machine can be restarted immediately after the exchange.

  Further, the invention according to claim 2 outputs an indication that the calculated slide pressure is overloaded when it is determined that the calculated slide pressure exceeds the excessive value in the memory setting operable pressure range corresponding to the detected crank angle. The press machine is configured to be able to display and output a light load when it is determined that it is possible and less than the underside value.

  In the press machine according to the second aspect of the present invention, when the calculated slide pressing force exceeds the excessive value in the memory setting operable pressure range corresponding to the detected crank angle, an overload and less than a small value are detected. In some cases, a light load is displayed and output. Handling becomes easier while reducing the burden on the operator.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
In the press machine 1, as shown in FIGS. 1 to 12, the calculated slide pressure PRik exceeds the excessive value (PR0u) of the memory setting operable pressure range (PR01 to PR0u) corresponding to the detected crank angle θi. Can generate and output a holp pressure rupture command signal and a press stop command signal, and can generate and output a press stop command signal when it is less than the underside value (PR01) of the pressurizing pressure range that can be stored and operated. ing.

  In this embodiment, when the detected crank angle θi belongs to a region other than the selected bottom dead center position region, the calculated slide pressure PRik exceeds the storage setting threshold (PRu) corresponding to the detected crank angle θi. In this case, the next position command pulse (MPTs) number can be reduced from the selected position command pulse number (Ns) by the set number (Nde), and if it is less than the memory setting threshold value (PRl), the next position command pulse (MP MPTs) can be increased from the number of selected position command pulses (Ns) by a set number (Nin), and the calculated slide pressure PRik is detected when the detected crank angle θi belongs to the selected bottom dead center position region. When the stored threshold value (PRu) corresponding to the crank angle θi is exceeded, the next slide position PT (h) is set and adjusted from the selected slide position. If it can be raised by (Pu) and is less than the stored threshold (PRl), the next slide position is formed to be lowered from the selected slide position by the set adjustment amount (Pd), and the calculated applied pressure is set. It is formed so that the slide pressure can be adjusted to a predetermined pressure quickly and with high accuracy when the threshold value is deviated.

  In FIG. 1, the drive mechanism of the press machine 10 includes a crank mechanism 11 including a crankshaft 12. The crankshaft 12 is rotationally driven by a slide drive motor 30 including an AC (alternating current) servomotor that is rotatably supported by and directly connected to the bearings 14 and 14. That is, the slide 17 is moved up and down while rotating (speeding) the slide driving motor 30 according to the number of selected position command pulses (MPTs) output according to the slide motion from the motion command unit 53 shown in FIG. Can be made. The slide drive motor 30 may be formed of a DC (direct current) servo motor or a reluctance motor having no permanent magnet or brush.

  In addition, you may connect the crankshaft 12 and the motor 30 indirectly via a gear (reduction gear). If a gear (reduction gear) is used, a higher applied pressure can be obtained compared to the direct connection shown in FIG. The relationship between the angle (θk) of the crankshaft 12, the rotation angle (θm) of the motor 30, and the reduction ratio γ (for example, 1/5) is θk = γ · θm. In the following description, since it is a direct connection, the crank angle (= motor rotation angle) is simply expressed as “θ”.

  The slide 17 in FIG. 1 is mounted on a frame body (not shown) so as to be slidable in the vertical direction, and is engaged with a weight balance device 18. Accordingly, if the crankshaft 12 is rotationally driven, the weight-balanced slide 17 can be driven up and down via the connecting rod 16. The mold 20 includes an upper mold 21 on the slide 17 side and a lower mold 22 on the bolster 19 side. Reference numeral 15 denotes a mechanical brake.

  The crankshaft 12 (the connecting rod 16) and the slide 17 of the press machine 1 are coupled via a suspension position structure type slide position adjusting mechanism 120 shown in FIG. The slide position adjusting mechanism 120 can adjust the slide position PT (h) in the vertical direction by expanding / contracting the relative distance in the vertical direction between the crankshaft 12 (the connecting rod 16) and the slide 17, and is roughly divided into a ball type and a wrist pin. An expression is considered. Since this embodiment has advantages such as small size, low cost, and little play, a ball type is adopted. The slide position adjusting mechanism 120 is also used for die height adjustment before the press operation.

  In FIG. 3, the slide position adjusting mechanism 120 can adjust the vertical relative distance (slide position) between the crankshaft 12 and the slide 17 in the unlocked state by the expansion / contraction driving signal and expand / contract by the expansion / contraction driving signal in the locked state. It is formed so that the vertical relative distance after the adjustment can be maintained as it is.

  Specifically, the connecting rod 16 (screw 16 a) and the adjustment screw shaft 121 (screw 121 a) are screwed (engaged), and a ball 122 is fixed to the lower end portion of the adjustment screw shaft 121. On the other hand, a ball cup 125 is attached to the slide 17 that is slidably guided by a column or the like so as to be movable up and down. 17a is a cylindrical body integrated with the slide 17, and accommodates the worm wheel 120WH, and 17b is a slide component that transmits the vertical movement of the ball 122 to the slide 17.

  The overload prevention device (126, etc.) will be described in detail when the setting operation possible pressure range comparison method described later is described.

  Since the connecting rod 16 and the slide 17 are connected via a spherical bearing structure, that is, a point structure formed by the ball 122 and the ball cup 125, the slide 17 is linearly moved in the vertical direction by the swinging motion of the connecting rod 16. Can do. Then, the worm wheel 120WH rotated by the worm screw 120WS is mounted on the cylindrical body 17a of the slide 17, while a pin 124 extending in the radial direction is attached to the ball 122, and the pin 124 is attached to the longitudinal groove 120a of the worm wheel 120WH. The two 122 and 120WH are connected so as to be capable of synchronous rotation.

  Therefore, if the worm screw 120WS is rotated by the slide position adjusting motor 120M in the unlocked state, the worm wheel 120WH is rotated. This rotation is transmitted to the ball 122, that is, the adjusting screw shaft 121 via the pin 124. Then, since the connecting rod 16 (female screw 16a) and the adjustment screw shaft 121 (male screw 121a) rotate relative to each other, the slide 17 can be moved in the vertical direction with respect to the connecting rod 16 connected to the crankshaft 12. That is, the slide position PT (h shown in FIG. 5) can be adjusted.

  Thereafter, when the crankshaft 12 is rotated, the connecting rod 16 is swung around the ball 122, whereby the slide 17 is stroked up and down to press-form a predetermined product at the adjusted slide position.

  Although not shown in FIGS. 3 and 10, etc., the slide position adjusting mechanism 120 is integrated with a state switching device. That is, in a normal state (when no unlock signal is output), the worm wheel 120WH is locked so that it cannot be rotated by a spring force, and when the unlock signal is output from the computer 80, the state switching device works. (Hydraulic supply), the slide position adjusting mechanism 120 can be forced against the spring force by the supplied hydraulic pressure to switch to the unlocked state.

  1, 2, and 6, the phase current signals Ui, Vi, and Wi corresponding to the phase motor driving currents Iu, Iv, and Iw of the AC servomotor (30) are detected by the current detector 73. In addition, an encoder 35 is connected to the motor 30.

  The encoder 35 has a large number of optical slits and optical detectors in principle, and outputs the rotation angle (crank angle) θ of the motor 30 (crankshaft 12). In this embodiment, the encoder 35 rotates. It includes a signal converter (not shown) that converts the angle θ (pulse signal) into a vertical position PT (pulse signal) of the slide 17 and outputs it.

  The structure of the encoder 125 is the same as that of the encoder 35.

  In FIG. 2, the setting selection command drive control unit includes a setting selection command unit 50, a position / speed control unit 60 (160), and a motor driving unit 70 (170). Further, a computer 80 is provided which is connected to these (50, 60, 70, 160, 170, etc.) and which constitutes the entire press operation drive control unit and monitoring unit shown in FIG. 10 necessary for a specific press operation. ing. The position / speed control unit 160 and the motor drive unit 170 for the slide position adjustment mechanism 120 may have different structures from those for the slide drive (60, 70).

  In FIG. 2, for convenience of explanation, the setting selection command unit 50 is composed of a motion command unit 53, a pressure pattern unit 55, a pressure conversion unit 57, a pressure comparison unit 58, and a slide position command unit. 59 is represented as a hardware block, which comprises the computer 80 of FIG. 10, that is, the ROM 82 storing each control program and the CPU 81 capable of executing the same, and the constant setting unit 56 is also a constant (for example, a crank). An operation panel 54 for inputting a radius L1, a connecting rod length L2, etc.), a ROM 82 for storing a control program for storing the input constant in the FRAM 83M, and a CPU 81 capable of executing the ROM 82.

  Of course, these [motion command unit 53, pressurizing pattern unit 55, pressurizing force converting unit 57, pressurizing force comparing unit 58, and slide position commanding unit 59] may be composed of a logic circuit, a calculator, a sequencer, and the like. For example, if the pressurizing force conversion unit 57 is composed of a sine ROM, a cosine ROM, a sum-of-products calculator, etc., the following (Equation 1), (Equation 2), and (Equation 3) can be calculated at high speed. It is possible to reduce the data processing burden on the computer 80 constituting the overall press operation drive control unit and the monitoring unit. Further, the constant setting unit 56, the speed setting unit 51 and the motion pattern selection unit 52, which will be described later, can also be configured from a switch box with a memory function, for example.

  In FIG. 10, a computer 80 includes a CPU (having a clock function) 81, a ROM 82, a RAM 83, a memory (FRAM... Electromagnetic derivative memory) 83M, an operation unit (PNL) 84, a display unit (IND) 85, an interface (I / F) Including 86, 87, 88, 89, it controls the drive control and monitoring of the entire press machine.

  The interface (I / F) 86 is connected to a position / speed control unit 60 (motor drive unit 70) for the motor 30, and the encoder 35 is connected to an interface (I / F) 87.

  The interface (I / F) 88 is connected to a position speed control unit 160 (motor driving unit 170) for the slide position adjusting mechanism 120 (motor 120M), and the encoder 125 is connected to an interface (I / F) 89. Yes. In addition, a state switching device (not shown) having a function of selectively switching the slide position adjusting mechanism 120 to either the locked state or the unlocked state is also connected.

  In the following description, it is assumed that various fixed information, control programs, computation (calculation) formulas, etc. are stored in the ROM 82 in a fixed manner or rewritable in the flash memory (FRAM 83M). You may form so that it may store in other possible memory [For example, a hard disk drive (HDD) etc.].

  Returning to FIG. 2, the setting selection command unit 50 (80) includes a speed setter 51 (84, 81, 82), a motion pattern selector 52 (81, 82), and a motion command unit 53 (81, 82). The position / speed control unit 60 is configured to be able to output a setting selection motion command signal, that is, a position command pulse MPTs. It should be noted that a setting / selection slide position command signal, that is, a position command pulse SPTs can be output to the position / speed control unit 160 related to the slide adjustment mechanism.

  The speed setting unit 51 (84) including the operation unit 84 can set the rotation speed (for example, 100 RPM) of the motor 30 by “manual”. However, when “automatic” is selected, the speed setting unit 51 (84) is selected and set in advance. The maximum rotational speed that has been used (for example, 120 RPM... 120 spm) is handled as being selected. The speed setting device 51 may be formed from an SPM setting device, a production speed setting device, or the like.

  The motion pattern selector 52 including the operation unit 84 includes a plurality of slide motion patterns (an elapsed time t from the start of operation corresponding to the crank angle θ, a slide position PT, and the like stored in the ROM 82 and displayed on the display unit 85). One storage relation information (selected slide motion) selected by key operation is output to the motion command section 53 (CPU 81, ROM 82).

  The selected slide motion (t-PT curve) is sent to the motion command section 53 (CPU 81, ROM 82) together with the motor rotation speed [or slide speed (so-called slide stroke number SPM)] set using the speed setting device 51 (84). ) Is output.

  Here, the motion command unit 53 (81, 82) as the slide motion drive control means has a position command pulse delivery system structure, and is a setting selection motion command signal, that is, a position in accordance with the selected slide motion (t-PT curve). The command pulse (group) MPTs is output to the position / speed control unit 60 (70) at a predetermined timing (for example, 5 mS or 1 mS).

  The motor 30 is directly connected to the crankshaft 12, the motor rotation speed set using the speed setter 51 is, for example, 120 RPM, and the number of pulses output from the encoder 35 per rotation (360 degrees) is 1 million pulses. When the payout cycle time is 5 mS, the number of pulses output per cycle (5 mS) is 10,000 pulses [= (1000000 × 120) / (60 × 0.005)].

  Depending on the set motor rotation speed and load size, as a measure to prevent sudden speed (position) changes, the acceleration section (the number of output pulses gradually increases) immediately after start-up, It is preferable to provide a deceleration zone (the number of output pulses gradually decreases) immediately before the press stops.

  Next, the slide position command unit 59 (CPU 81, ROM 82) as the slide position drive control means has a position command pulse delivery system structure as in the case of the motion command unit 53 (CPU 81, ROM 82), and the selected slide position. The set slide position signal, that is, the position command pulse (group) SPTs is output to the position / speed controller 160 (170) at a predetermined timing (for example, 5 mS or 1 mS).

  The pressure comparison unit 58 (81, 82) as a comparison determination unit compares whether or not the calculated slide pressure PRik exceeds (is less than) a storage setting threshold (PR1 to PRu) corresponding to the detected crank angle θi. Determine.

  The calculated slide pressure PRik is calculated by a pressure conversion unit 57 (81, 82) as a pressure calculation means. That is, the read memory setting threshold (PR1 to PRu), the crankshaft rotation angle θ detected by the encoder 35, and the motor drive current I [(| Iu | + | Iv detected using the phase motor current detector 73 | + | Iw |) / 3] and constants (L1, L2, etc.) are used to calculate the slide pressure PRik.

が成立するので、設定加圧力Ｆｓ（ＰＲｉｎ）とクランク角度θとから当該時のトルクＴを求めるには、

を演算すればよい。 Specifically, an arithmetic expression of the crank angle θ (θi), the slide pressure PR (PRik... Fs), and the torque T will be described with reference to FIG. The torque of the crankshaft 12 is T, the crank radius is L1, the length of the connecting rod 16 is L2, the force in the crank rotating direction is F1, the force in the connecting rod shaft direction is F2, the pressing force of the slide 17 is Fs, F1 and Fs The angle formed by α and the angle formed by F1 and F2 as β

Therefore, to obtain the torque T at that time from the set pressure Fs (PRin) and the crank angle θ,

May be calculated.

が成立する。したがって、検出クランク角度θ，モータ駆動部７０からの検出モータ駆動電流Ｉを用いてスライド加圧力ＰＲｉｋ（Ｆｓ）を迅速かつ正確に算出（検出）することができる。すなわち、構造複雑化およびコスト高化を招く格別な圧力検出装置（例えば、複数の歪ゲージ）を設けなくても、スライド加圧力ＰＲｉｋを算出することができるわけである。 Next, if the motor drive current is I and the motor torque constant is Kt, then T = Kt · I.

Is established. Therefore, the slide pressure PRik (Fs) can be calculated (detected) quickly and accurately using the detected crank angle θ and the detected motor drive current I from the motor drive unit 70. That is, the slide pressure PRik can be calculated without providing a special pressure detection device (for example, a plurality of strain gauges) that leads to structural complexity and cost increase.

  The constants (the crank radius is L1, the length of the connecting rod 16 is L2, etc.) are set and input by the constant setting unit 56 (84, 81, 82) and stored in, for example, the memory (83M). The current I can be read from the motor driving unit 70.

  Here, the set threshold values (PRl to PRu) are stored in the pressurization pattern data table as pressurization pattern data corresponding to the crank angle θ, and the pressurization pattern portion 55 (81, 82 also serving as data reading control means). ) Is read as storage setting threshold values (PRl to PRu) corresponding to the detected crank angle θi.

  The crank angle θ may be subdivided every 1 degree or less (for example, 0.5 degree or 0.01 degree). The sampling (detection timing) of the crank angle θ is speeded up in proportion to this subdivision. The threshold value may be set as PRlu ± ε, for example.

  In this embodiment, the pressurization pattern data table formed in the FRAM 83M has a setting corresponding to the crank angle θ in addition to the pressurization pattern data in which the crank angle θ is associated with the set threshold values (PR1 to PRu). The pressurizing force PRs (Fs), the set increase / decrease number (Nde, Nin) and the set adjustment amount (Pd, Pu) are also configured to be memorable.

  Moreover, these stored data (contents) can be displayed and output on the display unit 85 in a list format. Each value can be set and changed using the operation panel 84, and can be rewritten to a changed value by the rewrite control means (CPU 81, ROM 82). Accurate operation according to the actual machine (10) is possible, and handling is easy.

  For example, each set pressure in the selected bottom dead center position region (in this embodiment, θi = 179 degrees or / and 179.9 degrees ... near bottom dead center) is PRs (80 ton) and a set threshold value (allowable error) ) Is PR1 (72 ton) to PRu (88 ton). Note that 179.9 degrees is the approximate value processing of the bottom dead center position (180 degrees), because (Equation 1) to (Equation 3) do not hold when θ = 180 degrees. ].

  The set threshold values of the other areas (θi = 150, 151,..., 178 degrees) excluding the selected bottom dead center position area are PR1 (8, 8,..., 72 tons) to PRu (12, 13,..., 88 tons). is there. Here, the “other area excluding the selected bottom dead center position area” is substantially a previous area (lowering) from the top dead center side set position (for example, top dead center position) to the selected bottom dead center position area. Region ... in this embodiment, θi = 150, 151, ..., 178 degrees). This is because, in the ascending region (181, 182,..., 359 degrees), there is no idea of adjusting the pressing force, and it is preferable to set the slide ascending speed to the maximum rotational speed of the motor (30) exclusively for improving productivity.

  In this embodiment, the set threshold values (PR1, PRu) are set to 100 ± 10% by simply inputting the slide pressure (80 ton → 100%) corresponding to the crank angle θi (for example, 175 degrees). , 88ton) can be automatically set. This is to simplify handling. Depending on the crank angle θ (for example, 150 degrees, etc.), it is set to 100 ± 20%.

  The decrease signal generation / output means (CPU81, ROM82) for the next set number of times is detected by the area discrimination means (CPU81, ROM82) so that the detected crank angle θi (for example, 175 degrees) is the other areas (150, 151,..., 178 degrees), it is determined that the calculated slide pressure PRik (for example, 90 ton) exceeds the storage setting threshold [PRu (88 ton)] corresponding to the detected crank angle θi. In this case, the number of position command pulses for the next time (MPTs) is reduced from the number of selected position command pulses (Ns) by a set number [Nde ... for example, (| PRik−PRs | / PRs) · Ns]. The number of position command pulses (MPTs) for use is generated and output. This number (Ns−Nde) is temporarily stored in the work area of the RAM 83 until the crank angle θi (= 175 degrees) during the next stroke.

  That is, the number of position command pulses for the next time (MPTs) is calculated from the number of position command pulses (Ns) selected in advance [Nde = (| PRik−PRs | / PRs) · Ns = (| 90− 80 | / 80) · Ns = (1/8) · Ns)]. The number of pulses is reduced by [= (1.0-1 / 8) · Ns = (7/8) · Ns].

  Increase signal generation / output means (CPU81, ROM82) for the next set number of times is detected by the area discrimination means (CPU81, ROM82) so that the detected crank angle θi (for example, 175 degrees) is other areas (150, 151,..., 178 degrees), it is determined that the calculated slide pressure PRik (for example, 70 ton) is less than the storage setting threshold [PRu (72 ton)] corresponding to the detected crank angle θi. The position for the next time after correction is increased by increasing the number of position command pulses (MPTs) for the next time by a set number [Nin ... for example, (| Eik | / PRs) · Ns] from the number of selected position command pulses (Ns). The number of command pulses (MPTs) is generated and output. This number (Ns + Nin) is temporarily stored in the FRAM 83M until the crank angle θi (= 175 degrees) in the next stroke.

  That is, the number of position command pulses for the next time (MPTs) is calculated from the number of position command pulses (Ns) selected in advance [Nin = (| PRik−PRs | / PRs) · Ns = (| 70− 80 | / 80) · Ns = 0.1 · Ns)], which is the number of pulses increased by [(1.1) · Ns]. The cumulative number of the increased and decreased number of pulses is obtained, and when the slide top dead center position is stopped, the motion command unit 53 performs an operation such that the number of dispensed pulses in one cycle is constant at the stop position.

  Thus, the next time the stroke is increased / decreased by the increment / decrement (Nin or Nde) obtained last time from each selected position command pulse number (Ns) for each selected crank angle θi based on the selected slide motion (pattern) in each stroke. Because the slide descent speed can be adjusted by adjusting the number of position command pulses (MPTs), the variation (error) of the applied pressure PRi (slide position PTi) for each selected crank angle θi is gradually converged to the selected slide motion (pattern). The operation which maintained the slide pressure (position) based can be performed. Therefore, for example, high-quality deep drawing can be performed at a predetermined speed, and a pre-stage adjustment effect for making the bottom dead center position to be a predetermined position can be exhibited.

  Next, the slide position increase adjustment signal generation / output means (81, 82) has the detected crank angle θi within the selected bottom dead center position area (θi = 179 degrees or 179.9 degrees) by the area determination means (81, 82). In the case where it is determined that the calculated slide pressure PRik (for example, 90 ton) exceeds the storage setting threshold value (PRu = 88) corresponding to the detected crank angle θi (for example, 179.9 degree). Next, the next slide position [bottom dead center position (179.9 degrees)] PT for the next position in relation to the slide position adjustment mechanism 120 is set from the selected slide position (SPTs). ) Generates and outputs a slide position increase adjustment signal for increasing by the same amount.

  The slide position lowering adjustment signal generation output means (81, 82) determines that the calculated slide pressure PRik (for example, 70 Ton) is less than the storage setting threshold (PR1 = 72) corresponding to the detected crank angle θi. Is associated with the slide position adjusting mechanism 120, and the next slide position [bottom dead center position (179.9 degrees)] PT for the next stroke is set from the selected slide position (SPTs) to the set adjustment amount (Pd... A slide position lowering adjustment signal for lowering by (amount) is generated and output.

  That is, in the bottom dead center position region (near the bottom dead center), a direct slide position (pressurizing force) adjustment is adopted as compared with the increase / decrease adjustment (acceleration / deceleration adjustment) of the position command pulse MPTs. That is, the selected bottom dead center position PT (h) determined by the selected slide motion (pattern) is directly corrected (adjusted).

から算出される。なお、この算出スライド位置（ｈ）や（数１）〜（数３）により算出された加圧力ＰＲｉｋは、表示部８５にデジタル表示される。 Incidentally, the slide bottom dead center position (height h179, h179.9) within the bottom dead center position region (θi = 179 or 179.9 degrees) is the slide position PT (height h) shown in FIG. Is

Is calculated from The applied pressure PRik calculated from the calculated slide position (h) and (Equation 1) to (Equation 3) is digitally displayed on the display unit 85.

  The top dead center position pause signal generation / output means (CPU 81, ROM 82) generates and outputs a top dead center position pause signal when a slide position lowering adjustment signal or a slide position raising adjustment signal is generated and output. After the slide 17 is temporarily stopped by the top dead center position pause signal, the lock release signal of the slide position adjusting mechanism 120 is issued.

  Thus, if it is determined that the slide position is to be raised or lowered by the set adjustment amount (Pu or Pd) from the selected slide position (SPts), the top dead center side set point position at the end of the current slide stroke is set. The slide 17 is stopped, and in this stopped state, the slide position for the next time is moved up and down by a set adjustment amount (Pu, Pd) in association with the slide position adjustment mechanism 120. Therefore, since it only needs to be operated during the stop, the slide position adjusting mechanism 120 itself and the elevation control can be simplified.

  Next, the position / speed controller 60 (160) includes a position comparator 61, a position controller 62, a speed comparator 63, and a speed controller 64 shown in FIG. Equivalent) Si can be output. Note that the speed detector 36 is expressed in a form included in the position speed control unit 60 for convenience in illustration.

  First, the position comparator 61 includes a position command pulse position signal MPTs (SPTs) which is a target value signal from the motion command unit 53 (slide position command unit 59) and an actual slide position signal detected by the encoder 35 (125). The position deviation signal ΔPT is generated and output by comparing with FPT (feedback signal).

  The position control unit 62 accumulates the input position deviation signal ΔPT, multiplies it by the position loop gain, and generates and outputs a speed signal Sp. The speed comparator 63 compares the speed signal Sp with the speed signal (speed feedback signal) FS from the speed detector 36, and generates and outputs a speed deviation signal ΔS.

  The speed control unit 64 multiplies the input speed deviation signal ΔS by a speed loop gain, and generates and outputs a current command signal Si to the current control unit 71. This current command signal Si is substantially a torque signal.

  The motor drive unit 70 (170) includes a current control unit 71 and a PWM control unit (driver unit) 72. As shown in FIG. 7, the current control unit 71 includes phase current control units 71U, 71V, 71W. For example, the U-phase current control unit 71U multiplies the current command signal (corresponding to a torque signal) Si and the U-phase signal Up generated by the phase signal generation unit 40 to generate the U-phase target current signal Usi, and continues to the U-phase The target current signal Usi and the actual U-phase current signal Ui are compared to generate and output a current deviation signal (U-phase current deviation signal) Siu. The other V and W phase current control units 71V and 71W also generate and output V and W phase current deviation signals Siv and Siw. The phase motor current detector 73 detects each phase current (value) signal Ui, Vi, Wi and feeds it back to the current controller 71.

  The PWM control unit (driver unit) 72 includes a circuit (not shown) for performing pulse width modulation shown in FIGS. 9A and 9B, an isolation circuit 72A shown in FIG. 8A, and FIG. 8B. The driver 72B shown in FIG.

  That is, PWM signals Spwmu, Spwmv, Spwmw are generated from the current deviation signals Siu, Siv, Siw of each phase output from the current control unit 71. The pulse signal width (Wp) shown in FIG. 9B of the PWM signal Spwm is determined by the time width Wp of the ignition signal (+ U ignition signal or -U ignition signal), but a high load (for example, Siu has a large current). ) Is long and low load is short.

  The driver 72B is composed of an inverter circuit including a pair of transistors and diodes for each phase shown in FIG. 8B, and is switched (ON / OFF) controlled by each PWM signal Spwm (for example, + U, -U). Each phase motor drive current Iu, Iv, Iw can be output.

  According to the above configuration, in the press operation stop state in which the crankshaft 12 is stopped at the set point position (top dead center position .theta.i = 0 degrees), the drive control power source of the press comprehensive operation drive control unit (80). Is input. Also, the die height (set slide bottom dead center position) is adjusted using the slide position adjusting mechanism 120 as a die height adjusting mechanism.

  Here, when a press operation command is issued, a set slide position signal (position command pulse MPTs) is output based on the slide motion (t-PT curve) selected from the motion command unit 53 (81, 82) in FIG. ) The position / speed control unit 60 and the current control unit 71 that form the position / speed control system work, and the motor 30 is rotated positively (for example, counterclockwise) by the respective phase motor drive currents Iu, Iv, and Iw. The slide 17 descends via the crankshaft 12, the connecting rod 16, and the slide position adjusting mechanism 120 shown in FIG.

  That is, the selected position command pulse MPTs is output according to the slide motion for each selection cycle, and the slide is moved (lifted / lowered) while controlling the rotation of the slide drive motor 30 according to the number of selected position command pulses. During this period, the crank angle θi is detected (FIG. 12), and the slide pressure PRik corresponding to the detected crank angle θi is calculated using the equations [(Equation 1), (Equation 2), (Equation 3)]. The

  When the detected crank angle θi (for example, 177 degrees) belongs to a region other than the selected bottom dead center position region, the calculated slide pressure PRik exceeds the storage setting threshold value PRu corresponding to the detected crank angle θi. Is determined, the signal for reducing the number of next position command pulses (MPTs) by the set number (Nde) from the selected position command pulse number (Ns) is generated and output. If it is determined that the calculated slide pressure PRik is less than the memory setting threshold value (PRl) corresponding to the detected crank angle θi, the next position command pulse (MPTs) number is calculated from the selected position command pulse number (Ns). A signal to be increased by the set number (Nin) is generated and output.

  In the next slide stroke and in another region (the crank angle of 177 degrees), the number of selected position command pulses is increased / decreased by the previously set number (Nde or Sin) and output. The increase (decrease) of the set number can increase (lower) the slide pressure PRi by accelerating (decelerating) the slide lowering speed. That is, the slide pressure PRi can be corrected (maintained) to a predetermined pressure determined on the selected slide motion.

  When the calculated slide pressure PRik is within the set threshold (PR1 to PRu), the number of next position command pulses (MPTs) remains the number of selected position command pulses (Ns).

  On the other hand, when the detected crank angle θi belongs to the selected bottom dead center position region (for example, 179 degrees), the slide position when the calculated slide pressure PRik exceeds the storage setting threshold value PRu corresponding to the detected crank angle θi. A slide position increase adjustment signal for increasing the next slide position (h) by a set adjustment amount (Pu) from the selected slide position in association with the adjustment mechanism 120 (120M, 120Ws) is generated and output.

  When it is determined that the calculated slide pressure PRik is less than the storage setting threshold (PRl), a slide position lowering adjustment signal for lowering the next slide position (h) by a set adjustment amount (Pd) from the selected slide position. Is generated and output. That is, by correcting the slide position (hi) every time, the press pressure PRi near the slide bottom dead center position can be held at a predetermined value.

  Of course, when the calculated slide pressure PRik is within the threshold value (PR1 to PRu), the selected slide position (h), that is, the press pressure remains unchanged.

  Thus, even if there is a change in die height or material thickness during the press operation, the pressing force of the slide can be adjusted quickly and with high accuracy. Therefore, high quality products can be produced with high efficiency.

  Here, in addition to the point of aiming at quality improvement by the setting threshold value comparison method for adjusting the pressurizing force up to the above, the set operation possible pressurizing range comparison method for perfecting the mold protection as the feature of the present invention is described below. Will be described in detail with reference to FIGS.

  That is, when the calculated slide pressure PRik exceeds the excessive value (PR0u) of the memory setting operable pressure range (PR01 to PR0u) corresponding to the detected crank angle θi by the set operation possible pressure range comparison method. A holp pressure breaking command signal and a press stop command signal can be generated and output, and when it is less than the underside value (PR0l) of the pressurizing range that can be stored and operated, the press stop command signal can be generated and output.

  Here, the overload prevention device (126, etc.) is provided between the crankshaft 12 (specifically, the connecting rod 16) and the slide 17, as shown in FIG. With the hydraulic pressure held at a predetermined value), the relative position in the vertical direction between the crankshaft 12 and the slide 17 is fixed so that the applied pressure can be transmitted, and the ruptured state of the holp pressure (the state in which the indoor pressure is released) The relative position of the crankshaft 12 and the slide 17 in the vertical direction is liberated so that overload can be prevented.

  In FIG. 11, the set operation possible pressure range (PR01 to PR0u) is stored in the pressure pattern data table 83MT2 as pressure pattern data corresponding to the crank angle θ, and is read together with the detected crank angle θi (FIG. 11). 12 ST30). The motor current I is detected at ST31.

  In the pressurizing pattern data table 83MT2, in addition to the pressurizing pattern data in which the crank angle θi and the set operation possible pressurizing range (PR01 to PR0u) are associated, in this embodiment, the set pressurizing force PRs (Fs) and The set threshold values (PR1, PRu) are also formed so as to be memorable.

  In addition, these stored contents can be displayed and output on the display unit 85 in a list format. The setting can be changed using the operation panel 84 and can be rewritten by the rewrite control means (CPU 81, ROM 82). Accurate operation adapted to the actual machine (10) is possible, and handling is also simple.

  Here, the operable pressure range comparison / determination means (CPU 81, ROM 82) [the pressure comparison section 58 in FIG. 2] is applied at ST31 in FIG. 12 by the pressure conversion section 57 (81, 82) as the pressure calculation means. The slide pressurization pressure PRik calculated (ST32) using the detected data (current I) or the like is an excessive value (PR0u) [lowest value of the operable pressure range corresponding to the detected crank angle θi read in ST30. Side value (PR01)] is compared (ST33, ST36).

  By the operable pressure range comparison determining means (CPU 81, ROM 82) [pressure comparison section 58], the calculated slide pressure PRik (for example, 125 ton) is within the operable pressure range corresponding to the detected crank angle θi (177 degrees). If it is determined that the excess value (PR0u... 120 ton) has been exceeded (YES in ST33), the holp pressure rupture command signal generation / output means (CPU 81, ROM 82) generates and outputs the holp pressure rupture command signal (ST35). To do. As a result, the hydraulic pressure is released from the hydraulic chamber 126 and the holp pressure is broken. Further, the press stop command signal generation / output means (CPU 81, ROM 82) generates and outputs a press stop command signal (ST38). The slide motion drive control means (81, 82) inputs a stop signal to the circuit (60, 70) to forcibly stop the press. Therefore, protection of the mold 20 can be achieved.

  This press stop command signal generation output means (CPU 81, ROM 82) detects the calculated slide pressure PRik (for example, 35 ton) by the operable pressure range comparison determination means (81, 82) [pressure comparison section 58]. Even when it is determined that the operable pressure range corresponding to the angle θi (177 degrees) is less than the underside value (PR0l... 40 ton) (YES in ST36), a press stop command signal is generated and output (ST38). . Thus, production of defective products can be suppressed to a minimum, and broken punches can be replaced quickly.

  Further, the display control means (81, 82) is configured so that the calculated slide pressurization pressure PRik is detected by the pressurization range comparison / discriminating means (81, 82). ) Is exceeded (YES in ST33), an overload (for example, “overload”) is displayed and output (ST34), and is determined to be less than the underside value (PR0l) ( If YES in ST36, a light load (for example, “punch break”) can be displayed on the display unit 85 (ST37). Handling becomes easier while reducing the burden on the operator.

  Thus, according to this embodiment, it is possible to detect both overload and light load and forcibly stop the press, so that the mold protection can be perfected and the press can be safely stopped. Since it is possible to automatically detect a light load (for example, punch breakage), it is possible to reduce the mental and physical burden on the operator, to speed up punch exchange and to prevent a decrease in productivity.

(Second Embodiment)
In this embodiment, the basic configuration / function is the same as that of the first embodiment (FIGS. 1 to 12) except for the configuration of the slide position adjusting mechanism 150 shown in FIG. 13.

  In FIG. 13, a slide position adjusting mechanism 150 is formed integrally with a die height adjusting screw mechanism (die height adjusting mechanism) 130, and is switched between an unlocked state and a locked state unlike the case of the first embodiment (120). Even if not, the vertical relative distance between the crankshaft 12 and the slide 17 can be adjusted by the expansion / contraction driving signal, and the vertical relative distance after the expansion / contraction adjustment by the expansion / contraction driving signal can be maintained as it is.

  That is, the die height adjusting screw mechanism 130 having a relatively wide slide vertical adjustment range is restrained by the lock nut 131, but is the press operation of the slide position adjusting mechanism 150 having a relatively narrow slide vertical adjustment range? Regardless of whether or not the vehicle is stopped, the slide pressing force can be adjusted while elastically extending and retracting the expansion / contraction drive member (hollow cylindrical member 151) provided between the slide 17 without the idea of being in the unlocked state / locked state. ing.

  Specifically, the die height adjusting screw mechanism 130 includes an adjusting screw shaft 131 that includes a spherical bearing 132 that engages with a spherical body 16BL provided at the lower end of the connecting rod 16 and is connected to the worm wheel 139, as shown in FIG. , A lock nut 133 for locking the adjustment screw shaft 131, a worm screw shaft 138 screwed to the worm wheel 139, a motor (not shown) for rotationally driving the screw shaft 138, and an upper portion of the screw 131S to the adjustment screw shaft 131 , 151S and a hollow cylindrical member 151 whose lower part is fixed to the slide 17 via the cylinder device 140. In FIG. 13, 135 is a case, and 134 is a guide member.

  Therefore, when the pressure oil in the cylinder chamber 142 that forms the cylinder device 140 is released and the tightening force by the bolt member 152 is eliminated, the lock nut 133 is tightened and the worm screw shaft 138 is rotated, the worm wheel 139 and Since the adjustment screw shaft 131 (male screw 131S) rotates with respect to the hollow cylindrical member 151 (female screw 151S) fixed to the slide 17 via the pin member 134 inserted between the wheel 139 and the adjustment screw shaft 131. The die height (the vertical position of the bottom dead center position) can be adjusted by moving the slide 17 in the vertical direction.

  Next, the expansion / contraction drive member (151) constituting the slide position adjustment mechanism 150 is disposed between the slide 17 and the die height adjustment screw mechanism 130 and is formed to be extendable / contractable in the axial direction. In this embodiment, the telescopic drive member is formed from a hollow cylindrical member 151 that constitutes a part of the die height adjusting screw mechanism 130. The expansion / contraction force applying means is a means for applying an expansion / contraction force to the expansion / contraction drive member (hollow cylindrical member 151) to elastically expand / contract the member (151). The bolt member 152, the cylinder device 140, and the hydraulic supply means (hydraulic supply) Port 144, a switching control valve (not shown), a hydraulic pressure source, and the like).

  The cylinder device 140 includes a cylinder 141 fixed to the slide 17 and a piston 143 accommodated in the cylinder chamber 142 so as to be movable up and down. The cylinder 141 is formed with a hydraulic pressure supply port 144 for supplying hydraulic pressure between the upper end surface in the cylinder chamber 142 and the piston 143.

  The bolt member 152 is embedded in the hollow cylindrical member 151 so as to be movable up and down, the lower end thereof is fixed to the piston 143, and the other end is integrally connected to the hollow cylindrical member 151 via a lock nut 133. .

  The hydraulic pressure supply means is configured to be capable of supplying a hydraulic pressure of a predetermined pressure value (for example, the minimum pressure Pr0 to the maximum pressure Pr2) in the cylinder chamber 142 of the cylinder device 140. Electrohydraulic servo which is interposed in a pipe connecting the hydraulic pressure supply port 144 of the cylinder 141 and controls the internal pressure in the cylinder chamber 142 based on an expansion / contraction drive signal (for example, in proportion to the expansion / contraction drive signal). It comprises a mechanism (electrohydraulic servo valve, pressure sensor, servo amplifier, etc., not shown).

  Here, when hydraulic pressure is supplied into the cylinder chamber 142, the bolt member 152 is pulled and extended while the other end is fixed to the hollow cylindrical member 151, and the hollow cylindrical member 151 is compressed. As a result, the slide 17 moves upward by the amount of contraction of the hollow cylindrical member 151.

  The relationship between the internal pressure Pri in the cylinder device 140 and the expansion / contraction amount δ of the hollow cylindrical member 151 is defined as follows. That is, when the internal pressure Pri in the cylinder chamber 142 varies from the minimum pressure value Pr0 to the maximum pressure value Pr2, the hollow cylindrical member 151 is deformed by the maximum deformation amount (b−a = δr). Therefore, when an intermediate value (substantially median value) between Pr0 and Pr2 is preliminarily applied to the cylinder chamber 142 as the initial internal pressure Pr1, and the internal pressure is increased from that state, the hollow cylindrical member 151 contracts by the increase in the internal pressure. On the other hand, when the internal pressure Pri is decreased from the initial pressure Pr1, the hollow cylindrical member 151 extends by the amount corresponding to the decrease in internal pressure.

  The expansion amount δ of the hollow cylindrical member 151 with respect to an arbitrary internal pressure Pri (Pr0 ≦ Pri ≦ Pr2) is uniquely calculated based on the value of the internal pressure Pri. In this embodiment, the above-described initial internal pressure Pr1 is selected so that the maximum extension amount and the maximum contraction amount of the hollow cylindrical member 151 are equal. As a result, even if the vertical relative distance between the crankshaft 12 and the slide 17 changes due to the upward and downward fluctuations of the bottom dead center position, it can be accurately maintained at a predetermined distance (that is, the applied pressure).

  Thus, according to this embodiment, in addition to being able to achieve the same effects as in the case of the first embodiment, the slide position adjusting mechanism 150 is further provided with the hollow cylindrical member 151 and the stretching force applying means (bolt member). 152, cylinder device 140, hydraulic pressure supply means), and by adjusting the amount of expansion and contraction of the hollow cylindrical member 151 without the need for the concept of unlocking and specific work, the change in the applied pressure (bottom dead center position) is automatically performed. Therefore, the change in the applied pressure (bottom dead center position) during the press operation can be adjusted quickly and quantitatively with high accuracy. Compared with the first to third embodiments, the predetermined product accuracy can be stably and constantly maintained while further improving the productivity.

  In addition, since the hollow cylindrical member 151 is elastically expanded and contracted within the range of δr (= b−a) to adjust the pressure, the slide 17 does not fall indefinitely, so it is extremely safe. It is possible to adjust the pressure.

  When the hollow cylindrical member 151 is expanded and contracted, the female screw 151S of the hollow cylindrical member 151 and the male screw 131S of the adjustment screw shaft 131 exert pressure on each other in the axial direction, and the adjustment screw shaft 131 is locked. Therefore, the present slide position adjusting mechanism (bottom dead center position correcting device) can also serve as a locking means for the adjusting screw shaft 131.

  A mode different from the above, that is, the expansion / contraction drive member (151) is formed from a piezoelectric actuator that exhibits a piezoelectric effect, and the expansion / contraction force applying means is applied to a piezoelectric actuator by applying a high-voltage power supply to force the expansion / contraction drive (high pressure) Power supply device, charge injection circuit, charge discharge circuit), and is configured to adjust the slide pressure by automatically adjusting the expansion / contraction amount of the piezoelectric actuator by driving the piezoelectric driving means based on the expansion / contraction driving signal. Even can be implemented.

  That is, the hollow cylindrical member 151 is fixed to the slide 17 by a bolt member (similar structure to the bolt member 152), and a piezo actuator is interposed between the slide 17 and the hollow cylindrical member 151 instead of the cylinder device 140. If the structure is mounted, the distance between the slide 17 in which the piezo actuator is interposed and the die height adjusting screw mechanism 130 is adjusted so as to cancel the bottom dead center position change. Thus, the slide pressure (slide bottom dead center position) can be automatically adjusted quickly, safely and accurately while the is in the locked state.

According to the first aspect of the present invention, when the calculated slide pressing force exceeds the excessive value of the memory setting operable pressure range corresponding to the detected crank angle, a holp pressure breaking command signal and a press stop command signal are generated and output. If it is possible and less than the underside value, the press machine is formed so as to be able to generate and output a press stop command signal. Therefore, the following excellent effects can be obtained.
(A) It is safe because the mold protection can be perfected in the case of overload, and the press can be forcibly stopped by detecting both overload and light load.
(B) Since the mold protection can be perfected and handled easily, the servo motor drive system that can select various slide motions and obtain a large applied pressure greatly contributes to the widespread use of press machines including crank mechanisms. Can do.
(C) Since it is possible to automatically detect a light load (for example, punch breakage), it is possible to reduce the mental and physical burden on the operator, speed up the punch replacement, and restart immediately after the replacement. And maintain high productivity.
(D) Since it is not necessary to provide a special pressure detection device (sensor, sensor amplifier, etc.) for detecting the pressure, it can be realized at low cost and can be stably operated for a long time.

  According to the second aspect of the present invention, it is less than the underside value that the calculated slide pressure is overloaded when it exceeds the overside value of the memory setting operable pressure range corresponding to the detected crank angle. In the case of, the fact that the load is light is displayed and output, so that the same effect as in the case of the invention of claim 1 can be obtained, and in addition, the die height adjustment for the next time or the overload prevention device hold The pressure can be established quickly while reducing the burden on the operator, and the handling can be further simplified.

It is the schematic for demonstrating the press machine which concerns on the 1st Embodiment of this invention. Similarly, it is a whole block diagram for explaining a setting selection command part, a position speed control part, a motor drive part, and the like. Similarly, it is a longitudinal sectional view for explaining a slide position adjusting mechanism. Similarly, it is a figure for demonstrating the relationship between the torque T of a crankshaft, rotation angle (theta), and slide pressurization force Fs (PR). Similarly, it is a figure for demonstrating the relationship between rotation angle (theta) of a crankshaft, and the slide height h. Similarly, it is a figure for demonstrating the detail of a position speed control part and a motor drive part. Similarly, it is a figure for demonstrating a phase signal production | generation part and a current control part. Similarly, it is a figure for demonstrating a PWM control part (driver part). Similarly, it is a time chart for explaining the modulation operation of the PWM control unit (driver unit). Similarly, it is a block diagram for demonstrating a computer (a setting selection command part etc.). Similarly, it is a figure for demonstrating pressurization pattern data (a setting operation possible pressurization range is included.). Similarly, it is a flowchart for explaining the operation. It is a longitudinal cross-sectional view for demonstrating the slide position adjustment mechanism which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

10 Press Machine 12 Crankshaft 17 Slide 20 Mold 30 AC Servo Motor (Slide Drive Motor)
50 Setting selection command section [80]
59 Slide position command section [81, 82]
60, 160 Position speed control unit 70, 170 Motor drive unit 80 Personal computer (setting selection command unit, etc.)
83MT1, 83MT2 Pressure pattern data table 120 Slide position adjustment mechanism 120M Slide position adjustment motor 126 Hydraulic chamber (overload prevention device)
130 Die height adjusting screw mechanism 150 Slide position adjusting mechanism

Claims (2)

Slide drive motor can be directly or indirectly connected to the crankshaft, and the slide can be moved up and down while controlling the rotation of the slide drive motor according to the number of selected position command pulses output according to the slide motion at each selection cycle. To configure
An overload prevention device is provided between the crankshaft and the slide, which is configured to transmit pressure when the holp pressure is established and to prevent overload when the holp pressure is broken.
The pressurization range pattern data that associates the crank angle with the set operation possible pressurization range can be stored, and it corresponds to the detected crank angle using an arithmetic expression including the detected motor current and the detected crank angle. It is possible to calculate the slide pressure to be calculated,
When it is determined that the calculated slide pressure exceeds the excessive value of the memory setting operable pressure range corresponding to the detected crank angle, a holp pressure breaking command signal and a press stop command signal are generated and output, A press machine configured to be able to generate and output a press stop command signal when it is determined that the calculated slide pressing force is less than the underside value of the memory setting operable pressure range corresponding to the detected crank angle. When it is determined that the calculated slide pressure exceeds the excessive value in the memory setting operable pressure range corresponding to the detected crank angle, it can be output that an overload is possible and is less than the small value. The press machine according to claim 1, wherein when it is determined, the press machine is configured to be able to display and output a light load.

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