JP5506095B2 - Drive motor cooling device for press machine - Google Patents

Description

The present invention relates to a motor cooling device for driving a press machine.

As a cooling method for the whole motor, it is known that a motor cooling fan is operated at a variable speed by an inverter to cool the motor efficiently.
Japanese Patent Laid-Open No. 7-255197 describes that the temperature of a motor is measured by a temperature sensor, the inverter drive frequency is changed according to the measured temperature, and the motor is cooled by changing the rotational speed of the fan.
Japanese Patent Application Laid-Open No. 2004-180454 measures the current value flowing through the motor, estimates the temperature rise of the motor, and obtains the necessary air volume. And it describes changing an inverter drive frequency and cooling a motor so that the air volume may be ensured.
On the other hand, in press machines, there are the following methods for preventing overheating without increasing the size of the motor. That is, in Japanese Patent Application Laid-Open No. 2004-25191, a temperature sensor is provided in the motor, and the cooling fan is driven when the measured temperature becomes equal to or higher than a predetermined value. Furthermore, it is described that the working speed is reduced.

JP-A-7-255197 JP 2004-180454 A JP2004-25191

  Each of the inventions described in Patent Documents 1, 2, and 3 requires a sensor that knows the motor operating state and temperature state. If there is a sensor, there is a problem of reliability, and there is a problem that proper cooling cannot be performed when the sensor is abnormal. In addition, it is necessary to devise a sensor installation location. Furthermore, although the thing of patent document 2 performs temperature estimation from an electric current, since the emitted-heat amount is not determined only with an electric current, it is difficult to respond | correspond to the heat_generation | fever by factors other than an electric current.

The present invention has been made in view of the above problems, and provides a cooling device and method for a press machine drive motor that efficiently cools the drive motor of the press by a simple method and reduces the amount of power for cooling. The purpose is to do.

In order to achieve the above object, a first configuration of the present invention is a press machine that drives a slide by driving a drive motor at a variable speed according to a press operation pattern , and at least one cooling fan that cools the drive motor. And at least one fan drive unit that drives the cooling fan at a variable speed, and a calculation unit that controls the fan drive unit, the calculation unit calculates an average of the drive motor from the press operation pattern. A heat generation amount is calculated, a fan rotation speed command for maintaining the temperature of the drive motor at a predetermined temperature or less is obtained based on the average heat generation amount, and the fan drive unit is controlled using the obtained fan rotation speed command. It is characterized by controlling the control .

  The second configuration of the present invention is characterized in that the fan drive unit is an inverter device.

According to a third configuration of the present invention, in the first configuration, at least one of a torque command and a rotational speed command of the drive motor calculated based on the press operation pattern is used as the average heat generation amount of the drive motor. It is characterized by seeking .

Fourth configuration of the present invention, in the above first configuration, the average heating value of the drive motor, and at least one rotation speed command and torque command of the drive motor which is calculated based on the press operation pattern, and obtaining by using the thermal time constant of the heating unit to the cooling unit.

A fifth configuration of the present invention is characterized in that, in the first configuration, the rotational speed command of the cooling fan is corrected in consideration of an ambient temperature where the press device is placed .

According to a sixth configuration of the present invention, in a press machine that drives a slide by driving a drive motor at a variable speed according to a press operation pattern, a cooling fan that cools the drive motor and a fan that drives the cooling fan at a variable speed A driving unit; and a calculation unit that controls the fan driving unit. The calculation unit obtains an average heat generation amount of the drive motor from the press operation pattern, and based on the average heat generation amount, It has a function to calculate the fan rotation speed command to maintain the temperature below a predetermined temperature, and is used at the time of the previous press work when changing the press operation pattern and performing the next press work. The new fan rotation speed command is compared with the new fan rotation speed command calculated on the basis of the changed press operation pattern. If it is higher than the rotational speed command, the fan drive unit is controlled by the new fan rotational speed command, and if it is lower, the fan rotational drive unit by the fan rotational speed command used immediately before is controlled for a predetermined time, The fan driving unit is controlled by a new fan rotation speed command .

According to a seventh configuration of the present invention, in a press machine that drives a slide motor up and down by driving a drive motor at a variable speed according to a press operation pattern, a plurality (two or more) of drive motors that drive the slide, Each of the drive motors has at least one cooling fan, a plurality of fan drive units that drive the cooling fan, and a calculation unit that controls the fan drive unit, the calculation unit , It has a function of calculating an average heat generation amount of the plurality of drive motors from the press operation pattern, and calculating the fan rotation speed command for controlling the plurality of fans from the calculated average heat generation amount, respectively. When the press operation pattern is changed and the next press work is performed, the calculation is performed based on the respective fan rotation speed commands used at the time of the previous press work and the press operation pattern after the change. Are compared with each of the new fan rotational speed commands, and if the new fan rotational speed command is higher than the fan rotational speed command in the previous press operation pattern, the plurality of fans Each of the drive units is controlled, and if low, the plurality of fan rotation drive units are maintained for a predetermined time by the respective previous fan rotation number commands, and then the plurality of fan drive units are operated by the new fan rotation number commands. It is characterized by controlling each one .

According to an eighth configuration of the present invention, in the seventh configuration, the cooling fan drive unit is an inverter device.

According to a ninth configuration of the present invention, in the seventh configuration described above, a plurality of cooling fans are provided for each of the plurality of drive motors, and the calculation unit is configured to change the heat generation amount of each drive motor according to the amount of heat generated by each drive motor. An ON / OFF signal for controlling the number of operating fans of the plurality of fans corresponding to the drive motor is calculated, and the fan drive unit is ON / OFF controlled by the ON / OFF signal.

According to the problem-solving means described above, when the slide drive motor of the press machine is cooled by controlling the cooling fan, the heat generation amount of the drive motor estimated by the press operation pattern is used instead of the sensor, so that the efficiency is improved. The number of rotations and the number of cooling fans can be controlled. In addition, the amount of power for cooling can be reduced.

  As described above, according to the present invention, the heat generation amount can be estimated from the press operation pattern without detecting the temperature of the slide drive motor of the press machine by the sensor, so that the configuration of the cooling device is simplified. In addition, since the problem of failure of the sensor itself is eliminated, a more reliable device can be provided.

The figure which shows one Embodiment of this invention The figure which shows the control flow of the apparatus shown in FIG. The figure which shows the operation | movement of the flow shown in FIG. The figure which shows the other control flow of the apparatus shown in FIG. The figure which shows the operation | movement of the flow shown in FIG. The figure which shows other embodiment of this invention The figure which shows other embodiment of this invention. The figure which shows other embodiment of this invention.

Embodiments of the present invention will be described below.
Before describing specific embodiments, the principle of estimating the amount of heat generated by a slide drive motor of a press machine will be described.
First, the temperature rise Δθ during air cooling of the drive motor is calculated by the following equation.
Δθ = C × (heat generation amount Q of the heat generating portion) / (air volume) (Equation 1)
C: It is calculated by the following equation in consideration of a constant determined by the cooling structure and the cooling part area, or a time constant in which heat is transmitted to the cooling part.
Δθ = C × (heat generation amount Q of heat generating portion) × [1 / (1 + Tcs)] / (air flow)
... [Formula 2]
Tc: Time constant for heat transfer from heat generating part to cooling part
s: Laplace operator formula 2 is formulated with a first-order lag, but an object that cannot be formulated with a simple first-order lag is formulated accordingly. These constants are calculated in advance from the motor structure and specifications or by testing. Since the constant C in Equation 2 differs depending on the part to be cooled, it is determined appropriately.

The calorific value Q is calculated by the following equation.
Q = Kc × (current) ** 2 + Kh × (frequency) + Ke × (frequency) ** 2
... [Formula 3]
Kc: Constant related to copper loss
Kh: Of iron loss, constant related to hysteresis loss
Ke: Constant related to eddy current loss among iron loss When the motor is a permanent magnet synchronous motor, the frequency of Equation 3 is proportional to the number of revolutions and the current is proportional to the torque. Equation 3 for calculating the calorific value Q is an example, and can be appropriately changed depending on the characteristics of the motor including the cooling unit. For example, the mechanical loss may be added depending on the motor structure, and the constant in the formula varies depending on the mounting structure. Furthermore, if there is another factor that determines the amount of heat generation, or if there is another method, it may be estimated in consideration of it. For example, when the servo motor performs field control, the magnetic flux density changes, so Kh and Ke are not constant values. In this case, these are functions of magnetic flux and are given by mathematical formulas that take field control into consideration.
The calorific value Q under the constant operation condition fixed by Equation 3 can be calculated. Since the torque and the number of rotations during the press operation change every moment, the average heat generation amount Qa is an integral amount of the heat generation amount Q (torque, rotation number) with the torque and the rotation number as parameters for the time (t) of the press operation pattern. Can be calculated as
Qa = (1 / T) ∫Q (torque, rotation speed) dt (Equation 4)
T: Since the repetition period of the press operation pattern or the thermal time constant of the motor temperature rise is generally much longer than the press operation pattern repetition period T, the calorific value is obtained from the effective average torque and average rotation speed of a certain press operation pattern. May be.

As can be seen from the above, if the torque (or current) and the number of rotations in a certain press operation pattern are known, the average heat generation amount Qa can be predicted by Equation 4. From this, the temperature rise Δθ at a certain air volume can be predicted by the formula 1 or the formula 2. In other words, if the temperature rise limit Δθmax is determined, the air volume necessary for this is known. In the case of Formula 1, it becomes the following.
Airflow Δθ = (C / Δθmax) × (heat generation amount Q of the heat generation part) [Equation 5]
The temperature rise limit Δθmax can be determined from the temperature rise value at which the servomotor 1 can be continuously operated. That is, normally, the allowable maximum temperature θmax of the servo motor is determined by the insulation class. If the upper limit differs depending on the motor part, select the appropriate value according to the purpose of use and the components. The temperature rise limit Δθmax is Δθmax = θmax−ambient temperature (Equation 6)
Therefore, if the ambient temperature is the maximum temperature of the environment where the press machine is installed, Δθmax can be determined. Alternatively, since the ambient temperature varies depending on the air temperature and the operating conditions of other machines, the ambient temperature may be changed in consideration.

  As described above, if the press operation pattern (speed and torque) is known, the required air volume can be obtained. The operation pattern of the servo press is determined in advance prior to the continuous press operation when a die or the like corresponding to the press work is determined. The required torque and rotation speed of a certain press operation pattern are obtained from a simulation result at the time of pattern setting, a measurement result at the time of trial hit, or past operation history data.

Next, an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is an example applied to a press machine (servo press machine) driven by a servo motor. In FIG. 1, a main gear 3 is meshed with a gear 2 connected to a drive shaft 1 </ b> S of an AC servomotor 1, and a crank mechanism (a crankshaft 4 and a connecting rod 5) is connected to the main gear 3. The crank mechanism is formed so that the slide 6 can be moved up and down with respect to the stationary bolster 7. Since the crankshaft 4 is freely rotated by forward rotation, reverse rotation, and variable speed control of the AC servomotor 1, not only the crank mechanism but also other mechanisms such as a slide motion, a slide motion suitable for a molded body including a stationary state, Alternatively, various slide motions such as forward and reverse pendulum motions can be freely set, and switching between these can be used. For this reason, the precision, productivity, and adaptability with respect to a press-molded body can be expanded. As the AC servo motor 1, a synchronous motor using a permanent magnet, an induction motor, a reluctance motor, or the like can be used. Further, a DC servo motor may be used instead of the AC servo motor. Here, the AC servomotor 1 will be described as a permanent magnet synchronous motor. Further, FIG. 1 shows a crank press as an example, but a press machine having another structure, for example, a structure using a ball screw or a structure using a linear motor may be used.

The AC servo motor 1 is air-cooled by the cooling air from the cooling fan 8. The cooling fan 8 includes an AC motor that drives the fan itself.
The operation pattern of the slide 6 of the press machine is set by the operation pattern setting unit 11. The driving pattern can be input interactively from the keyboard or touch panel using the screen, or can be input using a PC. The operation pattern set by the operation pattern setting unit 11 is input to the motion calculation unit 12, and the rotation position and rotation speed pattern (hereinafter, position and speed pattern) of the actual operation of the servo motor 1 are calculated and generated by the motion calculation unit 12. The The servo motor control device 13 controls the servo motor 1 so that the position command and speed command calculated by the motion calculation unit 12 are obtained.

Next, since the speed of the servo motor 1 is calculated by the motion calculation unit 12, the heat generation amount calculation unit 21 calculates the average heat generation amount Qa using Equations 3 and 4. As described above, the required torque required for this calculation can be obtained from a simulation result at the time of pattern setting, a measurement result at the time of trial hit, or past operation history data. In this way, the average heat generation amount of the heat generating part can be calculated.
Since the calorific value can be calculated, the air flow corresponding to the predetermined temperature rise is calculated by Equation 1, 2 or 5, and the cooling command for obtaining this air amount, that is, the rotational speed command of the cooling fan 8 is used as the cooling command calculator 22. Calculate with. Since the relationship between the air volume and the rotational speed varies depending on the fan characteristics and the ventilation path, it is determined in advance by simulation calculations and experiments. The inverter 23 controls the rotational speed of the cooling fan in accordance with the rotational speed command from the cooling command calculation unit 22. In the case where the cooling fan 8 is an induction motor, the rotation speed command and the output frequency are substantially proportional, and therefore a frequency corresponding to the rotation speed command may be set.
In the above description, the inverter 23 is described as changing the AC frequency of the output. However, other devices that change the fan speed, such as a device that changes the input voltage of the cooling fan motor to change the rotation speed of the cooling fan, may be used. . Here, a device that varies the input voltage and changes the rotation speed of the cooling fan is also referred to as an inverter. As a device for changing the number of rotations of the cooling fan, other variable speed devices such as a matrix converter can be used.

FIG. 2 shows an operation flowchart for obtaining the rotational speed command of the cooling fan 8 when operated in this way, and FIG. 3 shows its operation characteristics.
FIG. 2 shows a calculation flow of the calorific value calculation unit 21 and the cooling command calculation unit 22. S1 to S16 are symbols attached to the respective calculation steps. This flow starts at a reasonable time interval. First, in S1, an operation pattern (servo motor rotation speed command with respect to time, torque pattern) is acquired. Next, in S2, the average calorific value is calculated based on this (Equations 3 and 4). In S3, the number of rotations of the cooling fan corresponding to this is commanded (using formula 5). At this time, the rotation speed command may be calculated every time this flow is executed, but it can be used if the operation pattern is not different from the previous execution. Also, since the operation pattern is determined together with the mold data, when the operation pattern is stored, the cooling fan speed command is also stored, and when the operation pattern is read, the cooling fan speed command is read. Also good.
Next, in S4, it is determined whether or not the rotational speed command obtained in S3 has changed from the rotational speed command output and stored as a command in the previous calculation flow.
When the rotational speed command increases (increases in S4), the rotational speed command newly calculated in S3 is output as a new rotational speed command (S5), and Flag = 1 is set (S6). Then, the process proceeds to S16. When the rotation speed command is the same (same in S4), the previously stored rotation speed command is output as it is (S7), and Flag = 1 is set (S8). Then, the process proceeds to S16. Further, when the rotational speed command decreases (decrease in S4), first, the value of Flag is determined (S9). When Flag = 1, the time at this time is stored (S10), and the process proceeds to S11. When Flag = 2, the process proceeds to S11 as it is. Then, it is determined whether or not a predetermined time ΔT has elapsed from the stored time (S11). That is, it is determined whether or not the current time−the stored time ≧ ΔT. If the predetermined time ΔT has not elapsed (NO in S11), the same rotational speed command as the previous time is output (S12) instead of the rotational speed command calculated in S3, Flag = 2 is set (S13), and the process proceeds to S16. . On the other hand, if the predetermined time ΔT has elapsed (YES in S11), the rotational speed command calculated in S3 is output as a new rotational speed command (S14), Flag = 1 is set (S15), and the process proceeds to S16.
Finally, the current rotational speed command of the cooling fan is stored (S16), and the flow ends. The inverter 23 is controlled according to the cooling fan rotational speed command thus obtained, and the rotational speed of the cooling fan 8 is controlled.

When the rotational speed command decreases due to the change of the operation pattern, the previous high rotational speed command is maintained for a predetermined time ΔT. This is because when the high rotational speed command is issued, since the amount of heat generated by the motor 1 is in a large state, the heat generated at this time waits for the heat to be dissipated and shifts to a low rotational speed command. The predetermined time is the time required for the amount of heat to be dissipated, and a time suitable for the press apparatus is set in advance. This time may be a constant value or may be changed according to the heat generation amount.

FIG. 3 shows an example of the operation when the control is performed as shown in FIG. FIG. 3 shows the calorific value calculation result of the motor 1 with respect to time and the rotation speed command of the cooling fan. In the description of FIG. 3, S1 to S15 correspond to the respective steps in FIG.
In FIG. 3, the power is turned on at time T0 and the press work by the press machine is started. At T0, the amount of generated heat is zero because it was stopped until then. The fan rotation speed at this time is also zero. The operation is started with the operation pattern at time T1 (S1 in FIG. 2; hereinafter, Sn is a symbol in FIG. 2). At this time, the calorific value is Q1 (S2), and the corresponding rotation speed command F1 is calculated (S3). Since the rotational speed command at the time before T1 is zero and the rotational speed command at T1 is F1, which is higher than the previous command (S4), the rotational speed command F1 is output (S5). Until the time T2, since the operation is performed with the same operation pattern, the amount of generated heat is not changed and the rotation speed command calculation is the same, so the rotation speed command F1 is maintained (S7).
Next, at time T2, the operation of the press machine is stopped (S1). At this time, the heat generation amount becomes zero (S2), and the rotation speed command corresponding to this is calculated as zero (S3). At this time, since it is lower than the previous rotational speed command F1 (S4), a threshold value (Flag value) is determined (S9). Since Flag = 1, the time T2 at this time is stored (S10). Although it is determined whether or not the predetermined time ΔT has elapsed from this point (S11), since the predetermined time ΔT has not elapsed, F1 which is the previous rotational speed command is maintained (S12), and Flag = 2 (S13). It is said.
Since the operation pattern is the same until T3, the rotation speed command zero is calculated, but since it is lower than the previous rotation speed command F1, it is determined whether the predetermined time ΔT has not elapsed since the stored time with Flag = 2, While ΔT has not elapsed, the previous command value F1 is output.
The press machine is operated again with a new operation pattern at time T3 when the predetermined time ΔT has not elapsed (S1). At this time, the calorific value is Q2 (S2), and the rotation speed command corresponding to this is calculated as F2 (S3). At this time, since the rotational speed command F1 is increased (S4), the rotational speed command F2 is output (S5).
The calculation at time T4 is the same as described above, and the rotation speed command F2 is maintained. Furthermore, operation of the press machine with a new operation pattern is started at time T5. The amount of heat generated with respect to this pattern is Q3, and the rotation speed command F3 corresponding to this is calculated, but it is lower than the previous rotation speed command F1 (S4) and is in the state of Flag = 2 (S9). ), It is determined whether ΔT has elapsed from time T4 (S11). Since ΔT has not elapsed until time T51, the rotational speed command F2 is maintained (S12).
At time T51, since ΔT has elapsed from time T4 in the state of the rotation speed command calculation described above (S11), a new rotation speed command F3 is output (S14) and is corrected to Flag = 1 (S15). .
Hereinafter, the cooling fan rotation speed is commanded as shown in FIG. In this way, the fan rotation speed corresponding to the heat generation amount is commanded. However, when the rotation speed command is lower than the previous command, the previous high rotation speed is maintained during ΔT. There is no worry.

According to this embodiment, a sensor for measuring the temperature of the servo motor is not required, and the fan rotation speed is commanded from the operation pattern. As a result, it is possible to reduce the electric power required for operating the fan with high reliability and to operate with high efficiency. Furthermore, since the fan is operated at a variable speed and the heat generation amount is small, that is, when the press load is light, the fan is operated at a low speed.
Needless to say, as another method for obtaining the cooling fan rotational speed command of FIG. 1, not only the above-described method but also another method may be used. For example, if the torque current and voltage, rotation speed, or equivalents are known from the operation pattern, the amount of heat generation can be grasped and the rotation speed can be calculated, so this can be calculated in a table or calculated with a simple function Etc. can be appropriately changed.
In the above description, the average calorific value is estimated for each press operation pattern. If the servo motor's thermal time constant is large, instead of estimating the calorific value for each press pattern, you can estimate several operating patterns together or estimate the operating status of the day comprehensively. Good.

Next, another embodiment of the present invention will be described. The basic concept is the same as that of the above-described embodiment, but is characterized in that the cooling fan is operated in consideration of a time constant in which heat is transmitted from the heat generating part to the cooling part.
FIG. 4 shows an operation flowchart for obtaining the rotational speed command of the cooling fan 8 of this embodiment, and FIG. 5 shows its operation characteristics. S21 to S32 are symbols attached to each calculation step.
FIG. 4 shows a calculation flow of the calorific value calculation unit 21 and the cooling command calculation unit 22. As in the previous embodiment, this flow starts at an appropriate time interval. First, in S21, an operation pattern (servo motor rotational speed command with respect to time, torque pattern) is acquired. Next, in S22, an average calorific value is calculated based on this (Equations 3 and 4). In S23, the number of rotations of the cooling fan corresponding to this is commanded (using formula 5). At this time, the rotation speed command may be calculated every time this flow is executed, but it can be used if the operation pattern is not different from the previous execution. Also, since the operation pattern is determined together with the mold data, when the operation pattern is stored, the cooling fan speed command is also stored, and when the operation pattern is read, the cooling fan speed command is read. Also good.
Next, in S24, it is determined whether or not the rotational speed command obtained in S23 has changed from the rotational speed command output and stored as a command in the previous calculation flow.
When the calculated rotational speed command increases (increases in S24), it is determined whether or not the rotational speed command newly calculated in S23 matches the rotational speed command previously commanded (S25). If they do not match (NO in S25), the rotational speed command is set to a value obtained by adding ΔF from the previous rotational speed command (S26), and the process proceeds to S32. If they match (YES in S25), the rotational speed command is set to the calculated value of the rotational speed command (S27), and the process proceeds to S32.
When the calculated rotational speed command is the same (same in S24), the rotational speed command is set to the previous rotational speed command value stored previously (S28), and the process proceeds to S32.
Further, when the calculated rotational speed command decreases (decrease in S24), it is determined whether or not the rotational speed command newly calculated in S23 matches the rotational speed command that was previously commanded (S29). When they do not coincide (NO in S29), the rotation speed command is set to a value obtained by subtracting ΔF from the previous rotation speed command (S30), and the process proceeds to S32. When they match (YES in S29), the rotational speed command is set to the calculated value of the rotational speed command (S31), and the process proceeds to S32.
In this step, the current cooling fan rotation speed command is stored (S32), and the flow is terminated. The inverter 23 is controlled according to the cooling fan rotational speed command thus obtained, and the rotational speed of the cooling fan 8 is controlled.
Here, the value ΔF for changing the rotational speed command is determined in consideration of the time constant at which heat is transmitted from the heat generating part to the cooling part and the start cycle of the flow of FIG. In addition, since the determination in S24 has an arithmetic error, filtering or determination with hysteresis may be performed.

FIG. 5 shows an example of the operation when the control is performed as shown in FIG. FIG. 5 shows a calorific value calculation result of the servo motor 1 with respect to time and a cooling fan rotational speed command. S21 to S32 in the description of FIG. 5 correspond to the respective calculation steps of FIG.
At time T0, the power is turned on and the press work is started. At T0, the vehicle is stopped and the amount of generated heat is zero. The fan rotation speed at this time is also zero. At time T11, the operation pattern is input and the press operation is started (S21). At this time, the average heat generation amount is Q11 (S22), and the corresponding rotation speed command F11 is calculated (S23). The rotational speed command at a time point before T11 is zero, the calculation of the rotational speed command at T11 is F11, which is higher than the previous command (increases in S24), and the previous rotational speed command at this time is zero. (S25), 0 + ΔF is output as the rotation speed command. Thus, as the time elapses, the rotational speed command gradually increases.
At time T111, since the previous rotational speed command is F11, it is equal to the rotational speed command calculation F11 (same in S24), and thereafter, the rotational speed F11 is commanded.
Next, at time T12, the press operation ends, the amount of heat generation becomes zero (S21, S22), and the corresponding rotation speed command calculation also becomes zero (S23). Since the calculated rotational speed at T12 is lower than the previous rotational speed command F11 (decrease in S24), F11−ΔF is output as the rotational speed command (S30). Thus, the rotational speed command gradually decreases as time elapses.
At subsequent times, the flow calculation of FIG. 4 is performed, and a rotational speed command as shown in FIG. 5 is output.
According to the present embodiment, since the rotational speed command is issued in consideration of the heat transfer characteristics to the cooling section, in addition to the effects of the previous embodiment, a more efficient operation can be performed.

FIG. 6 shows a case where there are two drive servo motors per servo press machine. The figure shows an example in which the two crankshafts independently drive the same slide. The slide operation is the same, but the load distribution in the slide differs depending on the mold structure and load conditions. The required torque is not always the same. At this time, the heat generation amounts of the servo motors 1-A and 1-B are not the same. FIG. 6 is a partial modification of FIG. 1, and the one configured in FIG. 1 is changed to two in FIG. That is, what is changed into two is the calorific value calculation units 21-A and 21-B, the cooling command calculation units 22-A and 22-B, the inverters 23-A and 23-B, and the cooling fan 8-A. And 8-B, servo motors 1-A and 1-B, drive shafts 1S-A and 1S-B, gears 2-A and 2-B, main gears 3-A and 3-B, crankshafts 4-A and 4 -B, connecting rods 5-A and 5-B.

In the configuration of FIG. 6, in addition to the operations and functions of FIG. 1, the heat generation amounts of the servo motors 1-A and 1-B are estimated separately, and the rotational speed commands of the cooling fans 8-A and 8-B are separately provided. It is possible to control. In particular, the present invention can be applied not only when the torque of each motor is different, but also when the cooling capacity of each servo motor is different, for example, when the constant of Equation 1 is different depending on the installation conditions of the servo motor.
Specific speed commands for the cooling fans 8-A and 8-B can be set as shown in the control flow of FIG. 2 or FIG. FIG. 6 shows a case where two servomotors are used for driving, but it is needless to say that three or more servomotors are the same.
Although FIG. 6 shows a configuration in which the torque of the servo motors is different, when multiple motors drive a common main gear, the torque of each motor is the same, and the motor cooling fan rotation speed command is the same. May be given.

FIG. 7 shows a case where one servo motor 1 is cooled by the cooling fans 8-A and 8-B. The figure shows an example in which two cooling fans are independently controlled to be turned ON / OFF according to the amount of heat generated by the servo motor 1.
FIG. 7 is a partial modification of FIG. The change is made by changing the cooling command calculation 22 to the cooling command calculation fan ON / OFF determination 24, changing the inverter 23 to the ON / OFF contacts 25-A and 25-B, and changing the cooling fan 8 to the cooling fans 8-A and 8- Changed to B.
With this configuration, in addition to the operations and functions of FIG. 1, the servo motor 1 can be efficiently cooled only by turning on / off the cooling fans 8-A and 8-B without using a variable speed device such as an inverter.
Although FIG. 7 shows the case where the servo motor 1 is cooled by two cooling fans 8-A and 8-B, it goes without saying that the same applies to three or more.

FIG. 8 shows a case where there are two drive servomotors per servo press device, and one servomotor is cooled by two cooling fans. The figure shows an example in which the two crankshafts independently drive the same slide. The slide operation is the same, but the load distribution in the slide differs depending on the mold structure and load conditions. The required torque is not always the same. At this time, the heat generation amounts of the servo motors 1-A and 1-B are not the same. Further, in the example in which the four cooling fans 8-A, 8-B, 8-C, and 8-D are independently controlled by ON / OFF control according to the heat generation amount of the servo motors 1-A and 1-B. is there.
Although FIG. 8 shows a case where two servo motors are cooled by four cooling fans 8-A, 8-B, 8-C, and 8-D, the same applies to the case where three or more cooling fans and servo motors are used. Needless to say, there are.
The above embodiments are merely examples and can be freely configured without departing from the gist of the present invention.

1, 1-A, 1-B Servo motor 1S, 1S-A, 1S-B Drive shaft 2, 2-A, 2-B Gear 3, 3-A, 3-B Main gear 4, 4-A, 4-B B Crankshaft 5, 5-A, 5-B Connecting rod 6 Slide 7 Bolster 8, 8-A, 8-B, 8-C, 8-D Cooling fan 11 Operation pattern setting unit 12 Motion calculation unit 13, 13- A, 13-B Servo motor control device 21, 21-A, 21-B Heat generation amount calculation unit 22, 22-A, 22-B Cooling command calculation unit 23, 23-A, 23-B inverter 24, cooling command calculation , Contact ON / OFF determination unit 25-A, 25-B, 25-C, 25-D ON / OFF contact

Claims (9)

In a press machine for driving a slide by a variable speed drive the drive motor in response to the press operation pattern, at least one cooling fan for cooling the drive motor, at least one fan drive to variable speed drives the cooling fan And a calculation unit for controlling the fan driving unit ,
The calculation unit calculates an average heat generation amount of the drive motor from the press operation pattern, calculates a fan rotation speed command for maintaining the temperature of the drive motor below a predetermined temperature based on the average heat generation amount, A drive motor cooling device for a press machine, wherein the fan drive unit is controlled using a calculated fan rotation speed command . 2. The drive motor cooling device for a press machine according to claim 1, wherein the fan drive unit is an inverter device. 2. The drive motor cooling device for a press machine according to claim 1, wherein at least one of a torque command and a rotation speed command of the drive motor calculated based on the press operation pattern is used for the average heat generation amount of the drive motor. drive motor cooling apparatus of a press machine and obtaining Te. In the drive motor cooling apparatus of a press machine according to claim 1, the average heating value of the drive motor, and at least one rotation speed command and torque command of the drive motor which is calculated based on the press operation pattern, It is determined using a thermal time constant from the heating portion to the cooling portion press machine drive motor cooling device according to claim. 2. The drive motor cooling device for a press machine according to claim 1, wherein the rotation speed command of the cooling fan is corrected in consideration of an ambient temperature where the press device is placed. apparatus. In a press machine for driving a slide by a variable speed drive the drive motor in response to the press operation pattern, at least one cooling fan for cooling the drive motor, at least one fan drive to variable speed drives the cooling fan And a calculation unit for controlling the fan driving unit ,
The calculation unit has a function of calculating an average heat generation amount of the drive motor from the press operation pattern and calculating the fan rotation speed command for maintaining the temperature of the drive motor below a predetermined temperature based on the average heat generation amount. And, when the press operation pattern is changed and the next press processing is performed, a new operation calculated based on the fan rotation speed command used at the time of the previous press processing and the changed press operation pattern. When the fan rotational speed command is compared, and the new fan rotational speed command is higher than the fan rotational speed command used until immediately before, the fan driving unit is controlled by the new fan rotational speed command, and the new fan rotational speed command is low <br/> after the fan rotation driving unit by the fan rotation speed command that has been used to control a predetermined time immediately before controlling the fan drive by the new fan rotation speed command Drive motor cooling apparatus of a press machine, characterized. In a press machine that drives a slide up and down by driving a drive motor at a variable speed according to a press operation pattern, a plurality (two or more) of drive motors that drive the slide, and at least for each of the plurality of drive motors One cooling fan, a plurality of fan drive units that drive the cooling fan, and a calculation unit that controls the fan drive unit , the calculation unit is configured to drive the plurality of drives from the press operation pattern It has a function of calculating an average heat generation amount of the motor, and calculating the fan rotation speed command for controlling the plurality of fans from the calculated average heat generation amount, and changing the press operation pattern to When carrying out the press working, each new fan speed calculated based on each fan rotation speed command used in the previous press working and the changed press operation pattern is used. When the new fan rotational speed command is higher than the fan rotational speed command in the previous press operation pattern, each of the plurality of fan drive units is controlled by the new fan rotational speed command. If lower, the plurality of fan rotation drive units are respectively maintained for a predetermined time by the immediately preceding fan rotation number command, and then the plurality of fan drive units are respectively controlled by the new fan rotation number command. Drive motor cooling device for press machine. 8. The drive motor cooling device for a press machine according to claim 7 , wherein the cooling fan drive unit is an inverter device. The drive motor cooling device for a press machine according to claim 7 , wherein a plurality of cooling fans are provided for each of the plurality of drive motors, and the calculation unit is configured to change each of the drive motors according to the amount of heat generated by each drive motor. Driving motor cooling of a press machine, wherein ON / OFF signals for controlling the number of operating fans of the plurality of fans corresponding to the driving motors are calculated, and the fan driving unit is ON / OFF controlled by the ON / OFF signals. apparatus.

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