KR20210021033A - Press device, terminal device, ball screw estimated life calculation method and program - Google Patents

Abstract

The present invention estimates the life time of the Ball Screw simply and with high precision. An initial load factor storage unit that stores an arbitrary load factor of the Ball Screw, a load value detection unit, a differential value calculation unit, an average axial load value calculation unit, an average rotation speed calculation unit, and a ball screw estimated life calculation unit. In the device including, the load value detection unit detects a load value in the axial direction applied to the ball screw, the differential value calculation unit calculates the amount of change in the detected axial load value, and the load factor adjustment unit is calculated. Adjust the arbitrary load factor of the Ball Screw stored in the initial load factor storage unit based on the amount of change in the load value. The average axial load value calculation unit calculates the average axial load value based on the detected load value, the average rotation speed calculation unit calculates the average rotation speed of the Ball Screw, and the ball screw estimated life calculation unit calculates the adjusted load. Based on the coefficient, the calculated average axial load value, and the calculated average rotational speed of the Ball Screw, the estimated life time according to the usage mode of the Ball Screw is calculated.

Description

Press device, terminal device, ball screw estimated life calculation method and program

The present invention relates to a press device, a terminal device, a ball-screw estimated life calculation method (ball-screw method) and a program.

A press apparatus such as an electric press is known in which a load is applied by vertically operating a ram with respect to a work.

In this type of press apparatus, the rotation of the motor is converted into linear motion to move the ram up and down, but a ball-screw is an important mechanical component for realizing the up and down operation of the ram.

Since an impact is applied to this Ball Screw by a load operation, deterioration proceeds. In order to operate with an appropriate load, it is required to estimate the life as accurately as possible.

In response to such a request, Patent Document 1 discloses a relationship between the axial load of the Ball Screw and the motor current value, a means for storing in advance the basic dynamic load rating of the Ball Screw, and a sampling interval. ) And a means for setting a time, and a means for recording the amount of use of the Ball Screw, and a coefficient of variation is measured at each sampling interval, and a rated fatigue life value calculated based on the measured value. A ball screw life monitoring device is disclosed that is configured to be able to update and displays the remaining life at each interval (see, for example, Patent Document 1).

: Japanese Unexamined Patent Application Publication No. Hei 5-187965

Therefore, in Patent Document 1, the estimated life time of the Ball Screw is calculated based _{on the average axial load F m} applied to the Ball Screw, the average rotational speed N _{m of the Ball Screw, and the load factor f w} determined according to the motion state. It is disclosed to do.

However, in general, the load factor f _w increases as the impact applied to the Ball Screw increases in operation, and as the value increases, the estimated life time decreases.

In addition, the range of values that the load factor f _w can take is generally 1.0 to 2.0, f _{w = 1.3 in the standard operating condition, and f w} = 1.8 in the case of driving with an impact.

Here, _{the life when the load factor f w} = 1.8 is calculated to be about 38% of the life when _{f w = 1.3, and how the load factor f w} is determined has a great influence on the length of the estimated life time. Gives

In other words, in order to prevent the Ball Screw from being damaged earlier than expected, it is also possible to calculate the predicted life short by setting the load factor as a large value, but in this case, even though there is still room for the Ball Screw's life, They are replaced, and as a result, there is a possibility that the ball screw and the man-hours required for its replacement become waste.

_{However, in Patent Literature 1, the load factor f w} is defined by dividing vibration and impact into four categories: “minor”, “small”, “medium”, and “large”. However, it cannot be said that the magnitude of the influence of the load factor f _{w on the estimated life time is sufficiently considered.}

In addition, in the technique of Patent Document 1, the estimated life time of the Ball Screw is obtained by the magnitude of the variation of the motor current, that is, the variation of the torque, but the variation of the torque is the variation of the load cell load value. It is generally difficult to verify that the accuracy is lower than the value and clearly correlates the magnitude of the impact and the life of the Ball Screw. Verification until the Ball Screw is actually damaged is performed in various environments and patterns of operation. Since it is difficult to perform until the size can be clearly defined, there is a problem that the method of the estimated life time of the Ball Screw cannot be said to be a simple and highly accurate method.

Accordingly, the present invention has been made in consideration of the above-described problems, and an object of the present invention is to provide a press device, a terminal device, a method and a program for calculating the estimated life of a ball screw with a simple and high accuracy.

Form 1: In one or more embodiments of the present invention, a load value detection unit that detects an axial load value applied to a Ball Screw, and an average axial load value based on the load value detected by the load value detection unit An average axial load value calculation unit that calculates, and an average rotation speed calculation unit that calculates the average rotation speed of the Ball Screw, and the average calculated in the load factor of the Ball Screw and the average axial load value calculation unit A press device that calculates an estimated life time according to a usage mode of the ball screw based on an axial load value and an average rotation speed of the ball screw calculated in the average rotation speed calculation unit, wherein in the load value detection unit A differential value calculation unit that calculates the amount of change in the detected load value in the axial direction, and a load factor adjustment unit that adjusts the load factor of the Ball Screw based on the change amount of the load value calculated in the differential value calculation unit. It proposes a press device characterized in that.

Form 2: In one or more embodiments of the present invention, the load factor adjusted by the load factor adjustment unit is an average axial load value calculated by the average axial load value calculation unit, and the average rotation speed calculation unit A press apparatus is proposed, characterized in that it is calculated based on the average rotational speed of the ball screw calculated from and the actual life time of the ball screw.

Form 3: In one or more embodiments of the present invention, the load factor adjusted in the load factor adjusting unit is based on the calculated estimated life time and the actual life time of the Ball Screw for which the estimated life time is calculated. Thus, a press device characterized in that it is further adjusted is proposed.

Form 4: In one or more embodiments of the present invention, the axial load value applied to the ball screw is a load value applied to the ball screw measured by a load cell, or the ball measured by the load cell. A press apparatus is proposed, which is a sum of a load value applied to a screw and a load value generated by acceleration/deceleration of the ball screw when the ram moves up and down.

Form 5: In one or more embodiments of the present invention, a load value detection unit that detects an axial load value applied to a Ball Screw, and an average axial load value based on the load value detected by the load value detection unit An average axial load value calculation unit that calculates, an average rotation speed calculation unit that calculates the average rotation speed of the Ball Screw, and the average shaft calculated in the load coefficient of the Ball Screw and the average axial load value calculation unit A terminal device having a calculation unit for calculating an estimated life time according to a usage mode of the ball screw based on a direction load value and an average rotation speed of the ball screw calculated in the average rotation speed calculation unit, wherein the load value detection unit A differential value calculation unit that calculates the amount of change in the load value in the axial direction detected in, and a load factor adjustment unit that adjusts the load factor of the Ball Screw based on the amount of change in the load value calculated in the differential value calculation unit. It proposes a terminal device characterized in that it is provided.

Form 6: In one or more embodiments of the present invention, a load value detection unit that detects an axial load value applied to the Ball Screw, and an average axial load value based on the load value detected by the load value detection unit An average axial load value calculation unit that calculates, an average rotation speed calculation unit that calculates the average rotation speed of the Ball Screw, and the average shaft calculated in the load coefficient of the Ball Screw and the average axial load value calculation unit Based on the direction load value and the average rotation speed of the Ball Screw calculated in the average rotation speed calculation unit, a calculation unit that calculates an estimated life time according to the usage mode of the Ball Screw, a differential value calculation unit, and a load factor A method for calculating the estimated life of a ball screw in a terminal device including an adjustment unit, comprising: a first step of calculating a change amount of a load value in the axial direction detected by the load value detection unit by the differential value calculation unit; and adjusting the load factor In addition, a method for calculating the estimated life of the ball screw is provided, comprising a second step of adjusting the load factor of the ball screw based on the amount of change in the load value calculated in the differential value calculating unit.

Form 7: In one or more embodiments of the present invention, a load value detection unit that detects an axial load value applied to a Ball Screw, and an average axial load value based on the load value detected by the load value detection unit An average axial load value calculation unit that calculates, an average rotation speed calculation unit that calculates the average rotation speed of the Ball Screw, and the average shaft calculated in the load coefficient of the Ball Screw and the average axial load value calculation unit Based on the direction load value and the average rotation speed of the Ball Screw calculated in the average rotation speed calculation unit, a calculation unit that calculates an estimated life time according to the usage mode of the Ball Screw, a differential value calculation unit, and a load factor A program for causing a computer to execute a method of calculating the estimated ball screw life in a terminal device including an adjustment unit, wherein the differential value calculation unit calculates a change in the load value in the axial direction detected by the load value detection unit. A program is proposed for causing a computer to execute a step and a second step of adjusting the load factor of the Ball Screw based on the amount of change in the load value calculated in the differential value calculating part by the load factor adjusting part.

According to one or more embodiments of the present invention, there is an effect that the life time of the Ball Screw can be estimated simply and with high accuracy.

1 is a diagram showing a structure of a press apparatus according to an embodiment of the present invention.
2 is a diagram showing an electrical configuration of a press device according to an embodiment of the present invention.
3 is a diagram showing an electrical configuration of a central processing unit according to an embodiment of the present invention.
4 is a diagram showing a conventional method of determining a load factor.
5 is a processing flow diagram according to an embodiment of the present invention.
6 is a processing flow diagram according to an embodiment of the present invention.

<Embodiment>

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

<Structure of press device>

Referring to Fig. 1, a structure of a press apparatus 100 according to the present embodiment will be described.

As shown in Fig. 1, the press apparatus 100 according to the present embodiment applies a desired pressure to a work W (to be processed) by an elevating motion. ) (1) and a ball-screw (2) that imparts a lifting motion (linear motion) to the ram (1), and these are installed in a press body (3).

Further, a servo motor 4 such as an AC servo motor serving as a driving source is also housed in the head frame body of a casing 5 connected to the press body 3. Then, the drive of the servomotor 4 is transmitted to the ball screw 2 through a pulley and a belt.

The ram 1 is formed in a cylindrical body as shown in Fig. 1. Specifically, a hollow portion is formed along the axial direction in the cylindrical body 1a formed in a cylindrical shape, and the screw shaft 2a of the ball screw 2 is inserted into the hollow portion. It is supposed to be.

Further, a nut body 2b of the ball screw 2 is fixed to a position in the ram 1 at an end portion of the cylindrical body 1a in the axial length direction.

At the tip end of the cylindrical body 1a, a kinetic column 9 is configured to be mounted, and in reality, the kinetic column 9 is in contact with the work W, Apply pressure appropriately.

Further, the strain gauge 9 is configured so that a strain gauge can be attached, and the pressure applied to the work W can be detected by the strain gauge.

In addition, as a reaction of the load applied by the strain column 9 to the workpiece W, the same load is applied to the ball screw moving the ram 1.

A cylindrical guide 6 is provided so as to surround the outer peripheral side of the cylindrical body 1a.

The cylindrical guide 6 is fixed in the casing 5 and is configured so that the ram 1 can move up and down along the tubular guide 6.

<Electrical configuration of press device>

As shown in Fig. 2, the press device 100 according to the present embodiment generates a servo motor driver 13, an encoder 14, a circuit unit 15, and a drive command pulse. A subsidiary 16, an encoder position counter 17, a control program storage unit 21, a display unit 22, an operation unit 23, and a temporary storage unit Consisting of (one hour) (24), initial load coefficient storage (25), load value storage (26), rotational speed storage (27), and CPU (central processing unit) (30). Has been.

The control program storage unit 21 stores a control program for the CPU (central processing unit) 30 to control the entire operation and processing of the press unit 100.

For example, in this embodiment, a differential value (main program related to the press work), as well as time series data of the load values stored in the load value storage unit 26 described later, differential value), a program that calculates the amount of adjustment of the load factor based on the calculated differential value and the initial load factor stored in the initial load factor storage unit 25 described later, and a load value storage unit described later A program that calculates the average axial load value based on the load value stored in (26), and calculates the average rotational speed of the Ball Screw based on the rotational speed of the Ball Screw stored in the rotational speed storage unit 27 described later. A program, a program for calculating the estimated life time of the Ball Screw based on the adjusted load factor, the calculated average axial load value, and the average rotation speed of the Ball Screw, and the like are stored.

The display unit 22 is a display device in which, for example, a liquid crystal panel and a touch panel are stacked and displays various types of information.

The display unit 22 may be provided in the press device 100, or may be another device or an independent device.

In this embodiment, information such as the calculated estimated life time of the Ball Screw is displayed, for example.

The operation unit 23 is configured with a touch panel, a tact switch, or the like for setting driving conditions and the like.

The temporary storage unit 24 is constituted by, for example, RAM, and stores temporary data.

In this embodiment, basic dynamic load ratings and the like are stored.

The initial load factor storage unit 25 stores an arbitrary load factor of the Ball Screw.

The initial load factor stored here is used as an initial value in the processing of the load factor adjustment unit 32 described later.

The load value storage unit 26 stores time series data in which the pressing position of the pressing unit detected by the circuit unit 15 as a load value detection unit or the encoder 14 and the load value at the pressing position are correlated.

The rotational speed storage unit 27 calculates the rotational speed of the Ball Screw having a relationship between this motor current and some kind from the motor current obtained from, for example, a drive command pulse generated from a drive command pulse generator 16 described later. The rotation speed obtained by the calculated function block (not shown) is stored.

The circuit unit 15 as a detection unit for detecting the load amplifies the signal for the resistance change of the strain gauge attached to the strain gage 9, converts the analog signal to a digital signal by A/D conversion processing, and then converts the analog signal to a digital signal. Output to the central processing unit) (30).

The drive command pulse generation unit 16 generates a desired drive command pulse based on a command from the CPU (central processing unit) 30, and generates driving through the CPU (central processing unit) 30. The command pulse signal is output to the servo motor driver 13.

Then, by driving the servomotor 4 under the control of the servomotor driver 13, the ram sliding mechanism 11 slides the ram 1 up and down.

The encoder 14 as a position detection unit is used to detect the rotation angle of the servomotor 4 and is used to detect the position of the ram 1.

In addition, the information of the encoder 14 is provided with positional information to the servomotor driver 13 in order to perform feedback control.

Further, the position information of the encoder 14 can be read by the CPU (central processing unit) 30 via the encoder position counter 17, and accordingly, the amount of movement of the RAM 1 is detected.

The CPU (central processing unit) 30 controls the entire operation of the press apparatus 100 according to the control program stored in the control program storage unit 21. In this embodiment, in particular, the process of estimating the life time of the Ball Screw is mainly performed.

<Electrical configuration of central processing unit>

As shown in Fig. 3, the central processing unit 30 according to the present embodiment includes a differential value calculation unit 31, a load factor adjustment unit 32, an average axial load value calculation unit 33, and an average It comprises a rotation speed calculation part 34 and a ball screw estimated life calculation part 35.

The differential value calculation unit 31 calculates an amount of change in the load value in the axial direction based on the axial load value applied to the ball screw stored in the load value storage unit 26.

Here, the amount of change in the load value in the axial direction is the amount of change per unit time of the load value in the axial direction, and this load value f _m is measured by the load cell as shown in Equation 1 below. It is calculated as the sum of the load value f _{m1 applied to the Ball Screw and the load value f m2} generated by acceleration/deceleration of the Ball Screw when the ram of the press moves up and down.

In addition, considering the load value due to acceleration/deceleration, in practical use situations (when extremely large acceleration does not continue), the load applied to the Ball Screw by acceleration _{f compared to the force applied to the Ball Screw during pressurization f m1 This is because m2} is small enough to be negligible, but if it _{is calculated as f m2} ≒ 0 in the case of no load, the calculation result is that the lifespan does not end indefinitely if there is no load.

As the variation of the differential value, which is the amount of change per unit time of the load value in the axial direction, is recognized, an instantaneous increase in load is recognized, and it can be considered that a motion with a large impact applied to the Ball Screw is performed.

_{Here, the differential value d[N/S], which is the amount of change in the load value f m} applied to the Ball Screw, is a linear regression line represented by the following equation (2) when the unit time is t[S]. Can be obtained by the equation of the slope of

Further, in the above, it is exemplified that the amount of change in the differential value per unit time is obtained, but the position of the ram at the time of the i-th sampling is p _i [mm], and the differential value per unit distance You can also find the amount of change.

The load factor adjustment unit 32 adjusts an arbitrary load factor of the Ball Screw stored in the initial load factor storage unit 25 based on the amount of change in the load value calculated by the differential value calculation unit 31.

Here, the arbitrary load factor is an average axial load value calculated by the average axial load value calculation unit 33 to be described later, the average rotation speed of the Ball Screw calculated by the average rotation speed calculation unit 34, and It is calculated by the ball screw estimated life calculation unit 35 based on the life time of the ball screw.

In addition, with respect to the load factor f _w , conventionally, as shown in Fig. 4, vibration or impact is reduced to 4 of "small", "small", "medium", and "large". It was divided into dogs, and the load factor f _w was determined by giving it a certain width.

However, for example, the life of the Ball Screw when the _{load factor f w} is f _w = 1.8 is about 38% of the life of the Ball Screw when _{f w = 1.3.} Big.

In addition, no quantitative measurement method has been established for "vibration/shock", which is an index for determining the load factor f _w.

Therefore, in the present embodiment, in the load factor adjustment unit 32, the initial load factor of the Ball Screw stored in the initial load factor storage unit 25 is used as a reference for the above conventional problem, and the differential value calculation unit ( The estimated life time of the Ball Screw is estimated using the _{load factor f w} obtained by adjusting the initial load factor based on the amount of change in the load value calculated in 31).

The average axial load value calculation unit 33 calculates the average axial load value based on the load value stored in the load value storage unit 26 that stores the load value detected in the circuit unit 15 as a load value detection unit. Calculate.

The average rotational speed calculation unit 34 calculates the average rotational speed of the Ball Screw.

The ball screw estimated life calculation unit 35 calculates a load factor adjusted in the load factor adjustment unit 32, an average axial load value calculated in the average axial load value calculation unit 33, and an average rotation speed. Based on the average rotational speed of the Ball Screw calculated in section 34, the estimated life time according to the usage mode of the Ball Screw is calculated.

Specifically, if the basic dynamic load rating is C[N], the load factor is f _w , the average axial load value is F _m [N], and the average rotational speed of the Ball Screw is N _m [min ^-1 ], the service life The rotational speed L[rev] is obtained by the formula shown in Equation 4, and the estimated life time L _h [h] is obtained by the formula shown in Equation 5. In addition, the average axial load value F _m [N] is obtained by Equation 6 with the number of samplings l and f _mi and the rotational speed of the Ball Screw sampled at regular intervals as n _{mi, and the average rotational speed} N _m [min ^-1 ] is obtained by Equation 7.

The obtained estimated life time is displayed on the display unit 22.

In Equations 4 and 5, the basic dynamic load rating C[N] and the load factor f _w are constants, and among them, the basic dynamic load rating C[N] is a ball screw used in the press device 100 It varies according to the type of the ball screw, and is a number published in catalogs, etc.

In addition, the average axial load value F _m [N] and the average rotational speed of the Ball Screw N _m [min ^-1 ] are variables, and the operating environment of the press unit 100 during sampling (simultaneous with sampling of the differential) (work ( It is changed by the method of applying the load and the difference in speed) due to individual differences in W).

<Processing of the press device>

In this embodiment, _{the estimated life time of the Ball Screw using the load factors f w of plural patterns is simultaneously calculated, and the load factor f w in the} calculation of the estimated life time of the Ball Screw closest to when the Ball Screw actually failed Then, by learning the differential value at that time in the press apparatus 100, a process of making the life prediction of the Ball Screw suitable for the user's unique use environment more accurate will be described.

Specifically, when the unbroken Ball Screw is replaced, it is determined that the user has determined that it is the optimum replacement time, and the load factor f _w with the closest life time is learned.

In addition, when the damaged Ball Screw is replaced, the load factor f _w is learned at which the life expectancy is closest and the life is shorter than the damaged timing.

In the following, using Figs. 5 and 6, a case in which the learning is divided into two processes of the first step and the second step will be described as an example.

<Learning process in the first stage>

Using Fig. 5, a first step learning process in the press apparatus according to the present embodiment will be described. Also, in the first step, processing is performed for the purpose of determining the _{approximate load factor f w.}

First, it is confirmed that the replacement or press of the ball screw is in an initial state (step S101). When the ball screw is replaced in step S101 (or the press is in an initial state), the average axial load F _m and the average rotational speed N _m of the ball screw are determined as predetermined values (for example, press device 100). _{As the average axial load F m} and the average rotational speed N _m of the Ball Screw, which are assumed in the design of, the load factor f _w is changed by 0.1 between 1.0 and 2.0, and the above equations 4 and 5 are Using the ball screw, the estimated life time of the ball screw is calculated by the estimated life calculating unit 35 (step S102).

_{Next, the average axial load value F m} [N] calculated by the average axial load value calculation unit 33 and the average rotational speed N _m [min- ¹ ] of the Ball Screw are sampled (step S103), and differential The differential value d[N/S] calculated by the value calculation unit 31 is sampled (step S104).

Then, using the average axial load value F _m [N] sampled in step S103, the average rotational speed N _m [min- ¹ ] of the Ball Screw, and Equations 4 and 5, the estimated life of the Ball Screw is calculated. The estimated life time of the Ball Screw is recalculated by the unit 35 (Step S105).

After that, the user judges whether or not the Ball Screw is actually damaged (Step S106). In step S106, when the user determines that the Ball Screw is damaged (YES in step S106), the calculated estimated life time is shorter than the actual life time, and the calculated estimated life time is the longest. The load coefficient f _w corresponding to is learned as a true value (step S108), the time average value of the differential value d sampled in step S104 is calculated (step S110), and the learning process of the first step is terminated.

On the other hand, when it is determined in step S106 that the ball screw has not been damaged ("NO" in step S106), the user judges whether or not replacement is necessary because the ball screw is not damaged but deterioration is in progress. (Step S107) When the user determines that the replacement of the Ball Screw is not necessary ("NO" in Step S107), the process returns to Step S103.

In addition, in Step S107, when the user determines that the Ball Screw needs to be replaced ("YES" in Step S107), the determined point is taken as the actual life time, and the load closest to the actual Ball Screw life time learning to the coefficient f _w as a true value (step S109), and ends the one and calculating the time average value of the differential value d (step S110), the learning process of the first stage sampling in step S104.

<The second stage of learning process>

With reference to Fig. 6, a second step learning process in the press apparatus according to the present embodiment will be described.

Further, in the second step, the load factor f _w learned in the first step is used as an initial value, and the load factor f _w is further finely adjusted from there to increase the accuracy.

First, the user judges whether or not the environment of the Ball Screw has changed significantly (for example, the work W has been changed to a completely different one) compared to the learning process in the first step (step S201).

At this time, when the user determines that the environment of the Ball Screw has changed significantly ("YES" in step S201), the second step is ended and learning is performed again from the first step.

On the other hand, when the user determines that the environment of the Ball Screw has not changed significantly ("NO" in Step S201), the user replaces the Ball Screw (Step S202), and the average axial load value and the Ball Screw are A time average value of the average rotational speed of and the differential value d is obtained (step S203).

In addition, replacement of the Ball Screw is performed by a Ball Screw whose specifications, etc. are not different at all before and after replacement.

Next, the CPU (central processing unit) 30 compares the time average value of the differential value d obtained in step S203 with the time average value of the differential value d obtained in step S110 of the first step (step S204). .

When the CPU (central processing unit) 30 determines that the time average value of the differential value d acquired in step S203 is greater than the time average value of the differential value d acquired in step S110 of the first step as a result of the comparison ( In step S204 ``YES''), it is determined that the operation with more impact than in the first step was performed, the load factor f _w was changed to a value smaller than the previous load factor f _w (step S206), and the process was stepped. Move to S207.

Also in the step S206, for example, the load factor f _w is smaller than the interval by 0.1 load factor of the previous f _w.

On the other hand, as a result of the comparison, the CPU (central processing unit) 30 determined that the time average value of the differential value d obtained in step S203 is less than the time average value of the differential value d obtained in step S110 of the first step. In the case ("NO" in step S204), it is determined that the operation with a lower impact than in the first step was performed, and the load factor f _w was changed to a value greater than the previous load factor f _{w (step S205), and the processing} Moves to step S207.

Also in the step S205, for example, increasing the load factor f _w to 0.1 interval from the load factor of the previous f _w.

The CPU (central processing unit) 30 operates the ball screw estimated life calculation unit 35 in step S207, _{and uses the load factor f w} changed in step S205 or step S206 to estimate the ball screw. The life time is calculated (step S207).

In step S208, the user judges whether or not the Ball Screw is damaged earlier than the estimated life time of the Ball Screw calculated in Step S207, and the Ball Screw is performed earlier than the estimated life time of the Ball Screw calculated in Step S207. When it is determined that it is damaged ("YES" in step S208), the CPU (central processing unit) 30 changes the load factor f _w to a value greater than the previous load factor f _w (step S210), and processes Returns to step S202.

Also in the step S210, for example, increasing the load factor f _w to 0.1 interval from the load factor of the previous f _w.

On the other hand, when the user judges that the Ball Screw has not been damaged earlier than the estimated life time of the Ball Screw calculated in Step S207 ("NO" in Step S208), the Ball Screw has not been completely damaged, but deteriorates. ) Is severe, so it is judged whether or not replacement is necessary (step S209), and when the user determines that the replacement of the ball screw is necessary ("YES" in step S209), the CPU (central processing unit) 30 a load factor f _w previous to the change in load factor value greater than f _w (step S210), and returns the process to step S202.

Further, when the user determines that the replacement of the Ball Screw is not necessary ("NO" in step S209), the CPU (central processing unit) 30 determines the estimated life of the Ball Screw before the replacement of the Ball Screw is required. It is judged whether the time has reached or not (step S211).

Then, when the CPU (central processing unit) 30 determines that the estimated life time of the Ball Screw has not been reached ("NO" in Step S211) before the Ball Screw needs to be replaced, the process proceeds to Step S203. Return to.

On the other hand, when the CPU (central processing unit) 30 determines that the estimated life time of the ball screw has been reached before the replacement of the ball screw is required ("YES" in step S211), the CPU (central calculation processing) device) 30 is changed to a value that is the load factor f _w than the previous load factor f _w (step S212), it returns the processing to step S203.

Also in the step S212, for example, the load factor f _w is smaller than the interval by 0.1 load factor of the previous f _w.

As described above, the press device 100 according to the present embodiment includes an initial load factor storage unit 25 that stores an arbitrary load factor of the Ball Screw, and a load value in the axial direction applied to the Ball Screw. The load value detection unit (circuit unit 15), the differential value calculation unit 31 for calculating the amount of change in the load value in the axial direction detected by the load value detection unit (circuit unit 15), and the differential value calculation unit 31 Based on the amount of change in the calculated load value, the load factor adjustment unit 32 for adjusting the arbitrary load factor of the Ball Screw stored in the initial load factor storage unit 25, and the load value detection unit (circuit unit 15). An average axial load value calculation unit 33 for calculating an average axial load value based on the detected load value, an average rotation speed calculation unit 34 for calculating the average rotation speed of the Ball Screw, and a load factor adjustment unit Based on the load factor adjusted in (32) and the average axial load value calculated in the average axial load value calculation unit 33 and the average rotational speed of the Ball Screw calculated in the average rotational speed calculation unit 34 Thus, it is provided with a ball screw estimated life calculation unit 35 for calculating the estimated life time according to the usage mode of the ball screw.

That is, in the press apparatus according to the present embodiment, the differential value is calculated by the load factor adjusting unit 32, which has the greatest influence on the accuracy of the ball screw estimated life time calculated by the ball screw estimated life calculating unit 35 Based on the amount of change in the load value calculated in the part 31, the estimated life time of the Ball Screw is calculated using the one obtained by adjusting the arbitrary load factor of the Ball Screw stored in the initial load factor storage unit 25. .

For this reason, it becomes possible to more accurately adjust the load factor stored in advance by using the differential value (the amount of change in the load value). Specifically, the load factor is increased or decreased by comparing the differential value in one method of use with the differential value in another method of use. By this method, when the use of the Ball Screw is changed, it becomes possible to obtain a load factor according to the usage mode. In addition, it becomes possible to calculate the estimated life time of the Ball Screw according to the usage mode by the load factor.

Therefore, it is possible to estimate the life time of the Ball Screw simply and with high accuracy.

In addition, the press apparatus 100 according to the present embodiment includes an arbitrary load factor, an average axial load value calculated by the average axial load value calculation unit 33, and the average rotation speed calculation unit 34. It is calculated based on the average rotation speed of the Ball Screw and the life time of any Ball Screw.

For this reason, it is possible to determine an approximate load factor by using an arbitrary Ball Screw up to its life and comparing the life predicted from the load value or rotation speed in the axial direction with the actual life.

Using the load factor obtained by this method, the estimated life time when a Ball Screw of the same type and size used so far is used in the same method of use is approximately determined.

Therefore, it is possible to estimate the life time of the Ball Screw simply and with high accuracy.

Further, in the press apparatus 100 according to the present embodiment, the axial load value applied to the Ball Screw is a load value applied to the Ball Screw measured by a load cell, or a load value applied to the Ball Screw measured by the load cell. It is the sum of the load value generated by acceleration/deceleration of the Ball Screw when the ram of the and press moves up and down.

Therefore, the load value in the axial direction applied to the Ball Screw is the load value applied to the Ball Screw measured by the load cell, or the load value applied to the Ball Screw measured by the load cell and the ram of the press move up and down. The use of the Ball Screw is changed by increasing or decreasing the load factor by comparing the differential value in one method of use with the differential value in another method of use, regardless of the sum of the load values generated by acceleration/deceleration of the Ball Screw. Even in the case, it becomes possible to obtain the load factor according to the usage mode.

Therefore, it is possible to estimate the life time of the Ball Screw simply and with high accuracy.

In addition, the press apparatus 100 of the present invention records the processing of the press apparatus 100 in a computer system or a computer-readable recording medium, and causes the program recorded in the recording medium to be read into the press apparatus 100 and executed. 100) can be realized. The computer system or computer referred to herein includes hardware such as an OS and peripheral devices.

In addition, "computer system or computer" is assumed to include the homepage provision environment (or display environment) when using the WWW (World Wide Web) system. Further, the program may be transmitted from a computer system or computer in which the program is accommodated in a storage device or the like, through a transmission medium, or to another computer system or computer by a transmission wave in the transmission medium. Here, the "transmission medium" for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.

Further, the program may be for realizing some of the above-described functions. Further, the above-described functions may be realized in combination with a computer system or a program already recorded in a computer, or a so-called difference file (differential program).

As described above, embodiments of the present invention have been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and designs within a range not departing from the gist of the present invention are also included.

For example, in the present embodiment, it is exemplified that the life estimation function of the ball screw is included as a function of a part of the press device 100, but is not limited thereto, and a terminal device having a life estimation function of the ball screw The device may be installed separately from the press device 100.

In addition, the life estimation function of the Ball Screw may be provided in a server on the cloud.

In addition, in the above embodiment, it has been described by exemplifying that the life of the Ball Screw is estimated mainly by the unique press device 100, for example, by using a plurality of the same press device 100 at the same time to share the learning data. Also good.

In this case, since a lot of learning data can be obtained from a plurality of identical press devices 100, the learning time can be shortened.

1: ram
1a: barrel-shaped body
2: Ball screw
2a: screw shaft
2b: nut body
3: press body
4: Servo motor
5: casing
6: Tubular guide
9: Kiwaeju
11: ram sliding mechanism
13: Servo motor driver
14: encoder
15: circuit part
16: drive command pulse generator
17: encoder position counter
21: control program storage unit
22: display
23: control panel
24: temporary storage unit
25: initial load factor storage unit
26: load value storage unit
27: rotation speed memory unit
30: CPU (central processing unit)
31: differential value calculation unit
32: load factor adjustment unit
33: average axial load value calculation unit
34: average rotation speed calculation unit
35: Ball screw estimated life calculation unit
100: press device
W: work

Claims (7)

Calculation of an average axial load value that calculates an average axial load value based on a load value detection unit that detects an axial load value applied to a ball-screw and a load value detected in the load value detection unit And an average rotational speed calculation unit for calculating an average rotational speed of the Ball Screw, a load factor of the Ball Screw, an average axial load value calculated in the average axial load value calculation unit, and the average A press device that calculates an estimated life time according to the usage mode of the Ball Screw, based on the average rotational speed of the Ball Screw calculated in the rotational speed calculation unit,
A differential value calculation unit that calculates a change amount of the load value in the axial direction detected by the load value detection unit;
A load factor adjustment unit that adjusts the load factor of the Ball Screw based on the amount of change in the load value calculated in the differential value calculation unit is provided.
A press device, characterized in that provided.
The method of claim 1,
The load factor adjusted by the load factor adjusting unit,
It is calculated based on the average axial load value calculated by the average axial load value calculation unit, the average rotation speed of the Ball Screw calculated by the average rotation speed calculation unit, and the actual life time of an arbitrary Ball Screw. Press device, characterized in that.
The method according to claim 1 or 2,
The load factor adjusted in the load factor adjustment unit,
The press apparatus, characterized in that further adjusted based on the calculated estimated life time and the actual life time of the ball screw for which the estimated life time is calculated.
The method according to any one of claims 1 to 3,
The axial load value applied to the ball screw is,
The load value applied to the Ball Screw measured by a load cell, or the load value applied to the Ball Screw measured by the load cell, and the acceleration/deceleration of the Ball Screw when the ram moves up and down. A press apparatus, characterized in that it is a value of a summation of a load value generated by a load).
A load value detection unit that detects an axial load value applied to the ball screw, an average axial load value calculation unit that calculates an average axial load value based on the load value detected in the load value detection unit, and the ball An average rotation speed calculation unit that calculates the average rotation speed of the screw, and the average axial load value calculated in the load factor and the average axial load value calculation unit of the Ball Screw and the average rotation speed calculation unit. A terminal device having a calculation unit that calculates an estimated life time according to a usage mode of the Ball Screw based on the average rotational speed of the Ball Screw,
A differential value calculation unit that calculates a change amount of the load value in the axial direction detected by the load value detection unit;
A load factor adjustment unit that adjusts the load factor of the Ball Screw based on the amount of change in the load value calculated in the differential value calculation unit.
Terminal device, characterized in that provided.
A load value detection unit that detects an axial load value applied to the ball screw, an average axial load value calculation unit that calculates an average axial load value based on the load value detected in the load value detection unit, and the ball An average rotation speed calculation unit that calculates the average rotation speed of the screw, and the average axial load value calculated in the load factor and the average axial load value calculation unit of the Ball Screw and the average rotation speed calculation unit. Calculation of the estimated life of the Ball Screw in a terminal device including a calculation unit for calculating an estimated life time according to the usage mode of the Ball Screw based on the average rotation speed of the Ball Screw, a differential value calculation unit, and a load factor adjustment unit. As a method,
A first step of the differential value calculation unit calculating a change amount of the load value in the axial direction detected by the load value detection unit;
The load factor adjustment unit performs a second step of adjusting the load factor of the Ball Screw based on a change amount of the load value calculated in the differential value calculation unit.
Ball screw estimated life calculation method, characterized in that provided.
A load value detection unit that detects an axial load value applied to the ball screw, an average axial load value calculation unit that calculates an average axial load value based on the load value detected in the load value detection unit, and the ball An average rotation speed calculation unit that calculates the average rotation speed of the screw, and the average axial load value calculated in the load factor and the average axial load value calculation unit of the Ball Screw and the average rotation speed calculation unit. Calculation of the estimated life of the Ball Screw in a terminal device including a calculation unit for calculating an estimated life time according to the usage mode of the Ball Screw based on the average rotation speed of the Ball Screw, a differential value calculation unit, and a load factor adjustment unit. As a program for executing a method on a computer,
A first step of the differential value calculation unit calculating a change amount of the load value in the axial direction detected by the load value detection unit;
The load factor adjustment unit performs a second step of adjusting the load factor of the Ball Screw based on a change amount of the load value calculated in the differential value calculation unit.
A program to run on your computer.

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