JP2015142933A - Electric press, and control method of electric press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric press and a control method of the same in which a workpiece can be replaced by human hands safely.SOLUTION: An electric press 1 comprises: a ram 1 that can be lifted by an electric motor 3 with respect to a workpiece; a drive power supply for driving the electric motor 3; a pair of movement operation buttons 42a, b for lifting the ram 1; and a pair of two-hand push operation buttons 41a, b for performing the blockage and insertion of a blocking part provided in a circuit which supplies power to the electric motor 3. The movement operation buttons 42a, b and the pair of two-hand push operation buttons 41a, b are arranged at distances where the buttons of each cannot be pushed by one hand simultaneously. The movement operation buttons 42a and the two-hand push operation button 41a are arranged at a distance so as to be pushed by one hand simultaneously, and the movement operation button 42b and the two-hand push operation button 41b are arranged at a distance so as to be pushed by one hand simultaneously.

Description

  The present invention relates to an electric press that safely performs a work of replacing a work by a human hand and a control method thereof.

  An electric press capable of controlling a load and a position with high accuracy using an electric motor is widely used in various fields. In this electric press, the work is replaced by a human hand, and in order to prevent the human hand from being caught between the presses, the operation is started with the two-hand push button, and the two-hand push operation is performed during the operation. Control was performed via software, such as stopping when the button was released.

JP 2005-125330 A

  However, since the conventional control is performed through software, there is a question about its reliability, and there is a demand to limit the drive of the motor in hardware in order to increase the reliability. Moreover, in order to raise safety | security further, there exists a request to stop by interrupting | blocking the power supply itself of the electric motor which is a drive source of an electric press. There is a demand not only for stopping in the middle of operation but also for ensuring safety by always shutting off the driving power source except during driving.

  The present invention has been proposed in order to solve the above-described problems of the prior art, and is provided with a circuit that cuts off the driving power supply when the two-hand push button is released. An electric brace that secures safety by blocking and a control method thereof are provided.

  In order to achieve the above object, the present invention provides an electric press including a ram that can be moved up and down with respect to a workpiece by an electric motor, and a driving power source that drives the electric motor. It is characterized by comprising a shut-off portion provided in a circuit to be connected, and a pair of two-hand pushing buttons that activate the lift operation of the ram by turning on the shut-off portion.

  In addition, a method for controlling an electric press including a ram that can be moved up and down with respect to a workpiece by an electric motor and a driving power source that drives the electric motor is also one aspect of the present invention.

It is a perspective view which shows the electric press of the 1st Embodiment of this invention. It is sectional drawing of the electric press of the 1st Embodiment of this invention. It is a top view which shows the setting pendant of the 1st Embodiment of this invention. It is a figure which shows the operation panel of the 1st Embodiment of this invention. It is a correlation diagram which shows the relationship of the input signal, button, and circuit diagram in the 1st Embodiment of this invention. It is a block diagram which shows the structure of the control part of the electric press of the 1st Embodiment of this invention. It is a relay circuit diagram of the electric press of the first embodiment of the present invention. It is a circuit diagram which shows the drive power supply interruption | blocking by the electromagnetic contactor of the electric press of the 1st Embodiment of this invention. It is a circuit diagram which shows the drive power supply interruption | blocking by the electromagnetic contactor of the electric press of other embodiment of this invention.

  Hereinafter, embodiments of an electric press according to the present invention will be described in detail with reference to the drawings. In the embodiment, description of overlapping drawings is omitted.

[1. First Embodiment]
[1-1. Constitution]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of the electric press according to the present embodiment. As shown in FIGS. 1 and 2, the electric press according to this embodiment includes a press ram 1 that applies a desired pressure to the workpiece W by a lifting operation, and a ball screw that provides the ram 1 with a lifting operation. 2 and the electric motor 3, and these are provided in the head frame of the casing 4.

  As shown in FIG. 2, the structure of the ram 1 is formed in a cylindrical body, specifically, a hollow body along the axial direction inside a cylindrical main body 1a formed in a cylindrical shape. Is formed so that the screw shaft 2a of the ball screw 2 can be inserted into the hollow portion. The axial end portion of the cylindrical main body 1a of the ram 1 is positioned at the end of the ball screw 2. The nut body 2b is fixed.

  A pressing body 1b is configured to be attachable to the lowermost part of the cylindrical main body 1a. In actuality, the pressing body 1b abuts on the workpiece W and applies an appropriate pressure. Further, the pressing body 1b may be configured so that a strain gauge can be attached, and the pressure applied to the workpiece W can be detected by the strain gauge.

  A cylindrical guide 5 is provided so as to wrap around the outer peripheral side surface of the cylindrical main body 1a. The cylindrical guide 5 is fixed in the casing 4, and the ram 1 is configured to be movable up and down along the cylindrical guide 5. The ram 1 is provided with an anti-sway guide 6 so as not to rotate on a plane orthogonal to the axial direction. Specifically, as shown in FIG. 2, the steady rest guide 6 includes a steady rest 6a, a guide portion 6b, and a connecting plate 6c. The steady rest 6a is directed upward from the lower end portion of the ram 1, Further, it is provided via a connecting plate 6 c so as to be parallel to the ram 1, and the steady rest 6 a moves up and down as the ram 1 moves up and down.

  Further, a guide portion 6b for allowing the steady rest rod 6a to pass through a predetermined location is fixed in the casing 4, and the steady rest rod 6a is raised and lowered along the guide portion 6b. When 1 moves in the up-down direction, it is configured not to idle in the cylindrical guide 5.

  A base 8 is provided on the lower side of the casing 4 through the vertical column 7 and immediately below the ram 1, and a driving operation panel 9 is provided in front of the base 8. A control unit 10 is provided inside the casing 4.

  The control unit 10 controls the operation and stop of the ram 1 based on the input signal. The control unit 10 includes an input of the IO-S power cut-off signal 11 from the multi-optical axis photoelectric sensor, an input from the emergency stop button provided on the setting pendant rod 30, and an emergency stop button provided on the driving operation panel 9. , Input from the two-hand push operation buttons 41a, 41b, input from the movement buttons 42a, 42b, and input from the mechanical initial button are accepted.

  The control unit 10 cuts off the power supply of the electric motor 3 that is the drive source of the electric press by the input of the IO-S power cut-off signal 11. The input of the IO-S power cut-off signal 11 is provided with a cut-off unit in three circuits connected to the control unit 10, and the contacts are referred to as S1, S2, and S3, respectively. The IO-S power cut-off signal 11 from the multi-optical axis photoelectric sensor input to the control unit 10 is a signal that transmits three circuits.

  The setting pendant rod 30 of FIG. 3 is connected to a connection connector (not shown) of the control unit 10. The setting pendant 30 includes a display unit 31 for displaying on a liquid crystal (LCD), a key operation panel 32 on which keys are arranged, a pendant emergency stop button 33, and a pendant connector 34 connected to the control unit 10. As shown in FIG. 5, the pendant emergency stop button 33 is a three-contact type, normally closed contact type (the contact opens when the emergency stop button is pressed). The three contacts are referred to as S1, S2, and S3.

  FIG. 4 shows details of the operation panel 9. The driving operation panel 9 is provided with a both-hands pressing operation button (left) 41a and a both-hands pressing operation button (right) 41b which cuts off the drive power when either one is released. These two-hand push operation buttons 41a and 41b release the cutoff of the drive power supply and instruct the start of the driving operation in the driving mode. The movement operation button (left) 42a and the movement operation button (right) 42b are teaching modes (modes in which conditions are set by setup), and have operation functions for lowering, temporarily stopping, and raising the ram 1. Specifically, when both the hand pressing operation buttons 41a and 41b are pressed to release the drive power supply cutoff and the ram 1 is lowered in this state, the moving operation button (left) 42a and the moving operation button (right ) When 42b is simultaneously pressed and paused, the movement operation button (left) 42a is pressed and only the movement operation button (right) 42b is released. Further, the ram 1 is configured to rise when the moving operation button (left) 42a and the moving operation button (right) 42b are released at the same time. As shown in FIG. 5, the two-hand push operation button (left) 41a and the two-hand push operation button (right) 41b are of a three-contact type and a regular time contact point (the contact is closed when the button is pressed). The three contacts are referred to as S1, S2, and S3. On the other hand, the movement operation button (left) 42a and the movement operation button (right) 42b are of a single contact type and a constant time road contact type (the contact is closed when the button is pressed).

  The operation operation panel 9 of FIG. 4 is provided with a mode switching key switch 43 for switching between a teaching mode for setting conditions in the setup, an operation mode for exclusively performing an operation, and a display RUN 45. The operation operation panel 9 indicates that the notation TEACH 44 indicating that the teaching mode is selected in accordance with the mode selection by the mode switching key switch 43 and the operation mode exclusively performing the operation operation are selected. The display RUN 45 is switched and displayed. In the present embodiment, the mode switching key switch 43 is a mode selection unit.

  Further, a driving operation panel emergency stop button 46 is provided on the driving operation panel 9 of FIG. As shown in FIG. 5, the operation panel emergency stop button 46 is of a three-contact type and normally closed contact type (the contact opens when the emergency stop button is pressed). The three contacts are referred to as S1, S2, and S3. By pushing this, the drive power supply stops in any state and the buzzer 47 sounds.

  When the power is turned on, a force initialization operation is necessary in order to see the position of the force at least once with a sensor or the like. When the power is turned on, the mechanical initialization request lamp 48 on the operation panel 9 in FIG. 4 is turned on. The operator sees this and presses the force initialization button 51. Even if the force initialization button 51 is pressed, the force initialization operation is not started. When the mechanism initialization button 51 is pressed, the force initialization request lamp 48 is turned off, the force initialization standby lamp 49 is turned on, and a standby state for starting the mechanism initialization is entered. Here, when the two-hand pressing operation button (left) 41a and the two-hand pressing operation button (right) 41b are pressed at the same time, the drive power is supplied and the force initialization operation is started. The force initialization standby lamp 49 is turned off and the force initialization completion lamp 50 blinks. When the mechanical initialization operation is completed, the mechanical initialization completion lamp 50 is turned on. The force initialization completion lamp 50 remains lit even when the driving power supply is cut off, and there is no need to re-initialize the force. As shown in FIG. 5, the force initialization button 51 is of a single contact type, a constant time path contact type (the contact is closed when the button is pressed).

  As shown in FIG. 6, the control unit 10 includes a central processing unit 60, which is controlled by a program written in the control program storage device 61. There is a temporary storage device 62 that stores temporary data, and a setting value storage device 63 that stores values set by the display unit 31 of the setting pendant 30 and the key operation panel 32. The ram 1 is slid up and down by rotating the motor 3 forward or backward via the motor drive control device 64 according to the output signal of the central processing unit 60.

  The central processing unit 60 includes a third contact (S3) of the two-hand push operation button (left) 41a, a third contact (S3) of the two-hand push operation button (right) 41b, a move operation button (left) 42a, a move operation. Button (right) 42b, mode switch key switch 43, operation panel emergency stop button 46 third contact (S3), force initialization button 51, pendant saddle emergency stop button 33 third contact (S3), IO- The state can be detected by inputting the third contact (S3) of the S power cut-off signal 11. In addition, the third contact point (S3) of the simultaneous two-hand push signal 1 and the third contact point (S3) of the simultaneous two-hand push signal 2, which will be described later, can also be input to detect the state.

  A buzzer 47, a force initialization request lamp 48, a force initialization standby lamp 49, and a force initialization completion lamp 50 are connected to the output from the central processing unit 60, and a buzzer is sounded and the lamp is lit / flashed. Can be made.

  7 and 8 show a drive power supply cutoff circuit. In S71 of FIG. 7, the coil of the relay R71 is driven by the contact of the two-hand push button (left) Sl. In S72, the coil of the relay R72 is driven by the contact point of the two-hand push button (right) Sl.

  In S73, the timer T73 is driven by the relay R71-S1 contact. The timer T73 is a delay timer in which the coil is driven with a delay of a set time after energization, for example, 0.5 seconds. When this timer is turned off, the coil drive stops. In S74, a relay R71-S1 contact and a timer T73-S1 contact are provided. These contacts drive a relay R74 by connecting B contacts that are turned off when the coil is driven in series. With this configuration, the relay R74 is energized in a pulsed manner for a delay time of the timer T73, for example, 0.5 seconds.

  In S75, the timer T75 is driven by the relay R72-S1 contact. The timer T75 is a delay timer that is driven after being energized, for example, a delay timer in which the coil is driven with a delay of 0.5 seconds. When this timer is turned off, the coil drive stops. In S76, a relay R72-S1 contact and a timer T75-S1 contact are provided. This contact drives the relay R76 by connecting the B contact which is turned off when the coil is driven in series. With this configuration, the relay R76 is energized in a pulsed manner for a delay time of the timer T75, for example, 0.5 seconds.

  In S77, the relay R77 and the coil of the simultaneous two-hand push signal 1 are driven by the relay R76-S1 contact and the relay R76-S1 contact. Since the relays R74 and R76 are energized in the form of pulses of timers T73 and T75, for example, 0.5 seconds, respectively, only when the left and right of the two-hand push button are pressed almost simultaneously, The coil will be driven. In S78, once the relay R77 is energized, it continues to energize at the relay R77-S1 contact. The relay R77 constitutes a self-holding circuit, and continues to be energized as long as the relay R71 and the relay R72 are energized even after the pulse-like energization of the relay R74 and the relay R76 is finished. When either one of the two-hand push operation buttons 41a and 41b is released, the coil drive of the relay R77 is stopped.

  The relay R87 and the coil of the simultaneous two-hand push signal 2 are driven by the same circuit shown in S81 to S88 of FIG. The relay R87 is energized when the left and right sides of the two-hand push operation buttons 41a and 41b are pushed almost simultaneously, and when either one of the two-hand push operation buttons is released, the coil drive of the relay R87 stops.

  As shown in FIG. 8, the simultaneous two-hand push signal 1, the relay R77-S2 contact, the operation panel emergency stop button Sl, the pendant emergency stop button Sl, and the IO-S power cut-off signal Sl are connected in series. Drive the coil. When any of the four contacts breaks, the energization of the electromagnetic contactor 79 stops and the contacts leave.

  Similarly, the simultaneous two-hand push signal 2, the relay R87-S2 contact, the operation panel emergency stop button S2, the pendant emergency stop button S2, and the IO-S power cut-off signal S2 are connected in series to drive the coil of the magnetic contactor 89. . When any of the four contacts is cut off, the magnetic contactor 89 is de-energized and the contacts are released.

  As described above, power is supplied to the motor drive circuit by pressing both hand push buttons almost simultaneously with the work replacement window switch and the multi-optical axis photoelectric sensor signal closed without pressing the emergency stop button. By connecting two electromagnetic contactors with the same circuit configuration in series, even if a single failure such as welding of a relay occurs, the electromagnetic contactor will not be cut off, resulting in power supply to the motor drive circuit. Will stop and is safe. Further, the drive power cutoff circuit described above is configured only by hardware such as a button (switch), a relay, a timer, and an electromagnetic contactor, and is not related to the central processing unit 60 in FIG. For this reason, even if there is an error in the control program stored in the control program storage device 61, the drive power supply is not affected, and it can be said that the reliability is high from this viewpoint.

[1-2. Action]
In the electric press of the present embodiment having the above-described configuration, when pressing is performed on an installed work, a pair of both-hand press operation buttons 41a in (1) normal mode and (2) teaching mode. , B are simultaneously pressed to turn on the circuit breaker connecting the electric motor 3 and the drive power source, and the ram 1 is moved up and down. In the following, the ram 1 is moved up and down in (1) normal mode and (2) teaching mode. Hereinafter, the circuit at the time of raising / lowering the ram 1 in each mode will be described.

(1) Normal mode In the operation mode, the electric motor 3 and the drive power source are connected and the ram 1 is moved up and down. The descending amount of the ram 1 is lowered by the descending amount set in the teaching mode.

  First, the user operates the mode switching key switch 43 to set the operation mode. Then, the user operates both-hand pressing operation buttons 41a and 41b. Thereby, the interruption | blocking part of the circuit which connects the electric motor 3 and drive power supply is thrown in, the electric motor 3 drives, and the raising / lowering operation | movement of the ram 1 is started. As a result, the ram 1 descends and press is performed on the installed workpiece, and then the ram 1 rises.

(2) Teaching mode In the teaching mode, the lowering amount of the ram 1 in the raising / lowering operation of the ram 1 in the normal mode is set. When setting the amount of descent of the ram 1, the user operates the two-hand push operation buttons 41a and 41b and the movement operation buttons 42a and 42b.

  First, the user operates the mode switching key switch 43 to set the teaching mode. Then, both the hand-pressing operation buttons 41a and 41b are pressed to release the drive power supply cutoff. In this state, when the ram 1 is lowered, the movement operation button (left) 42a and the movement operation button (right) 42b are simultaneously pressed.

  By releasing only the movement operation button (right) 42b while the ram 1 is being lowered, the ram 1 being lowered is temporarily stopped. Further, when the movement operation button (left) 42a and the movement operation button (right) 42b are released at the same time, the ram 1 rises. At this time, the position of the lowered ram 1 becomes the lowering amount of the ram 1 set in the teaching mode.

  The ram 1 was lowered, the ram 1 was temporarily stopped, and the ram 1 was raised by a combination of push operation buttons 42a and 42b. During this time, both the hand-pressing operation buttons 41a and 41b are kept pressed. When the two-hand push operation buttons 41a, 41b are released, the drive power is cut off and the raising / lowering of the ram 1 is stopped.

  In addition, in this electric press, the motor 3 and the drive power supply can be switched by input from the operation panel emergency stop button 46, the pendant emergency stop button 33, and the IO-S power cut-off signal other than releasing both-hand push operation buttons 41a and 41b. The circuit to be connected is shut off.

  In the above description, the electromagnetic contactor 89 is used to cut off the drive power supply, but the drive power supply may be cut off by a semiconductor relay circuit instead. Since it takes time to close the electromagnetic contactor, the amount of time is wasted. From the viewpoint of shortening the working time, speeding up with a semiconductor relay is effective.

  FIG. 9 shows an example of a circuit that cuts off the drive power supply by connecting one electromagnetic contactor 79 and one electromagnetic contactor 89 in series. In this example, the simultaneous two-hand push signal R77 is not input on the electromagnetic contactor 79 side. In this circuit, the electromagnetic contactor 79 starts to close at the stage where the workpiece replacement is completed and the IO-S power shutoff signal S1 is closed. Specifically, when the workpiece exchange window is closed, the electromagnetic contactor 79 starts to close. Thereafter, when the two-hand push operation buttons 41a and 41b are pressed, the simultaneous two-hand push signal 2 is closed, and this time the electromagnetic contactor 89 side is closed. By adopting such a configuration, the closing start of the electromagnetic contactor 79 side can be accelerated as much as possible, the dead time can be reduced as much as possible, and the tact time can be shortened. In such a configuration, the signals S1 and S2 from the pendant emergency stop button and the IO-S power cut-off signals S1 and S2 are duplicated in terms of an electric circuit.

  In the electric press of this embodiment as shown in FIG. 9, when the press is executed, the two-hand pressing operation buttons 41a and 41b are single in terms of electric circuit, but the operation is actually started and the ram is started. In order to start descending, the S3 contact input of the two-hand push button is not performed until the central processing unit 60 judges, and it is duplicated including software, so that sufficient safety can be secured. .

[1-3. effect]
In the electric press of this embodiment as described above, the teaching mode and the operation mode are switched. In the teaching mode, instructions for raising, stopping, and lowering the ram are given by the movement operation buttons 42a and 42b. By performing teaching with the moving operation buttons 42a and 42b that cannot be operated with one hand, a highly safe electric press can be realized.

  In the present embodiment, the moving operation button 42a and the moving operation button 42b are arranged at a distance that cannot be pressed simultaneously with one hand, and the two-hand pressing operation button 41a and the two-hand pressing operation button 41b are arranged at a distance that cannot be pressed simultaneously with one hand. did. Accordingly, it is possible to prevent the workpiece from being operated while the movement operation buttons 42a and 42b and the two-hand pressing operation buttons 41a and 41b are pressed with one hand. Thereby, a highly safe electric press can be realized.

  In the present embodiment, power is turned on to the power press 1 by pushing the two-hand pushing operation buttons 41a, 41b, and the power is shut off by releasing the two-hand pushing operation buttons 41a, 41b. A highly safe electric press can be realized by shutting off and turning on the power with the two-hand push operation buttons 41a, 41b that cannot be operated with one hand.

  In the present embodiment, the circuit that supplies electric power to the electric motor 3 is further provided with a second blocking unit, and the circuit is blocked by the operation of the emergency button. Thereby, by pressing this button in an emergency, the power supply to the electric motor 3 can be cut off, and the operation of the electric press can be stopped.

  In the present embodiment, the circuit that supplies electric power to the electric motor 3 is further provided with a third blocking unit, and the circuit is blocked according to an IO-S signal from the outside. The IO-S signal is a signal that is mainly detected from various sensors such as a work exchange window switch and a multi-optical axis photoelectric sensor. Thereby, various sensors are retrofitted, and the supply of electric power to the electric motor 3 can be cut off by an input signal from the sensors, and the operation of the electric press can be stopped.

[2. Other Embodiments]
Although the embodiments of the present invention have been described above, various omissions, replacements, and changes can be made without departing from the scope of the invention. And this embodiment and its deformation | transformation are included in the invention described in the claim, and its equivalent range while being included in the range and summary of invention.

  In the present embodiment, a shut-off portion provided in a circuit that connects the electric motor 3 and the drive power supply is turned on, and a pair of two-hand push operation buttons 41 a and 41 b are provided in order to activate the lifting operation of the ram 1. In the present application, in order to ensure the safety of the user, the electric motor 3 and the drive power source are connected only while the two buttons are touched. Therefore, in addition to the buttons, other switches can be used. As this switch, it is also possible to use a contact such as another switch that turns on the blocking portion only while the user is touching it.

  In the present embodiment, one of the movement operation buttons and one of the two-hand pressing operation buttons are arranged at a distance that can be simultaneously pressed with one hand. Since both buttons are arranged at a short distance, there is a possibility that the user mistakenly presses the buttons. For this reason, a display unit for displaying the type of the button being pressed can be further provided.

  In the teaching mode, the ram 1 is lowered by simultaneously pressing the movement operation buttons 42a and 42b, and the ram 1 is temporarily stopped by releasing only the movement operation button (right) 42b, the movement operation button (left) 42a and the movement operation. The ram 1 was raised by simultaneously releasing the buttons (right) 42b. However, the combination of the movement operation buttons 42a and 42b to be pressed is not limited to this. For example, the ram 1 may be lowered by pressing only the movement operation button (right) 42b, and the ram 1 may be temporarily stopped by simultaneously pressing the movement operation buttons 42a and 42b.

  Moreover, in order to improve safety | security, the alerting | reporting part which alert | reports to a user that it is raising / lowering operation | movement of a ram can also be provided. As this alerting | reporting part, the audio | voice generating part which generate | occur | produces a warning sound, the warning display part which calls attention with a display or light, etc. can be provided.

DESCRIPTION OF SYMBOLS 1 ... Ram 1a ... Cylindrical main body 1b ... Press body 2 ... Ball screw 2a ... Screw shaft 2b ... Nut body 3 ... Electric motor 4 ... Casing 5 ... Cylindrical guide 6 ... Shaking prevention guide 6a ... Shaking prevention rod 6b ... Guide part 6c ... Connecting plate 7 ... Column 8 ... Base 9 ... Operating operation panel 10 ... Control part 30 ... Setting pendant 31 ... Display part 32 ... Key operation panel 33 ... Pendant emergency stop button 34 ... Pendant connector 41a ... Double-handed push button (left) )
41b ... Two-hand push button (right)
42a ... Move operation button (left)
42b ... Move operation button (right)
43 ... Mode switch key switch 44 ... Notation TEACH
45 ... Display RUN
46 ... Operation panel emergency stop button 47 ... Buzzer 48 ... Mechanical initialization request lamp 49 ... Mechanical initialization standby lamp 50 ... Mechanical initialization completion lamp 51 ... Mechanical force initialization button 60 ... Central processing unit 61 ... Control program storage Device 62 ... Temporary storage device 63 ... Setting value storage device 64 ... Motor drive control device 71 ... Relay R
72 ... Relay R
73 ... Timer T
74 ... Relay R
75 ... Timer T
76 ... Relay R
77 ... Relay R
79 ... Electromagnetic contactor 87 ... Relay R
89 ... Electromagnetic contactor

Claims (10)

In an electric press comprising a ram that can be raised and lowered with respect to the workpiece by an electric motor, and a drive power source that drives the electric motor,
An electric press comprising: a shut-off portion provided in a circuit connecting the electric motor and the drive power source; and a pair of two-hand push operation buttons that activate the lift operation of the ram by turning on the shut-off portion. A teaching mode and a mode selection unit that switches between operating modes are further provided.
2. The electric press according to claim 1, further comprising a pair of movement operation buttons for instructing to raise, stop, and lower the ram in the teaching mode. The pair of movement operation buttons and the pair of both-hand push operation buttons are arranged at a distance where the same type of buttons cannot be simultaneously pressed with one hand,
One of the movement operation buttons and one of the two-hand pressing operation buttons are arranged at a distance that can be simultaneously pressed with one hand,
The electric press according to claim 2, wherein the other of the movement operation buttons and the other of the two-hand pressing operation buttons are disposed at a distance that can be simultaneously pressed with one hand. The two-hand push button is
4. The device according to claim 1, wherein the blocking portion provided in the circuit is turned on by pressing the button, and the blocking portion provided in the circuit is blocked by releasing the button. The electric press according to any one of claims. The circuit for supplying power to the electric motor is provided with a second shut-off unit that shuts off and on the circuit,
The electric press according to any one of claims 1 to 4, wherein the second blocking portion is operated by one button. The circuit for supplying power to the electric motor is provided with a third shut-off unit that shuts off and on the circuit,
The electric press according to claim 5, wherein the third blocking unit operates according to an external IO-S signal. The IO-S signal is an input signal of three systems,
The electric press according to claim 6, wherein one of the input signals is invalidated. The circuit for supplying electric power to the electric motor is provided with the same kind of cutoff unit that operates by the same signal in parallel,
The electric press according to any one of claims 1 to 7, wherein if the input signal is different in each of the blocking portions, it is determined that there is a problem.   The electric press according to claim 2, further comprising a display unit that displays the type of the two-hand pressing operation button being pressed and the movement operation button. In a control method of an electric press comprising a ram that can be raised and lowered with respect to a workpiece by an electric motor, and a drive power source that drives the electric motor,
A process for shutting off a shut-off portion provided in a circuit connecting the electric motor and the drive power source is performed by a pair of two-hand pushing buttons that activate the lift operation of the ram by turning on the shut-off portion. Press control method.