JP7028625B2 - Electric press, load determination method and program - Google Patents

Description

The present invention relates to an electric press, a load determination method and a program.

A servo press that drives a ram by a servo motor is known (see, for example, Patent Document 1). This servo press can control the position and speed of the ram with high accuracy. Therefore, it is easy to combine with peripheral equipment such as a transport device for loading and unloading the work, and has a feature that productivity can be improved.

Further, this type of servo press is characterized in that, for example, the load value is constantly monitored in the press-fitting operation to determine the pass / fail of the press-fitting operation.
As a specific judgment criterion, as shown in FIG. 19, data consisting of a pressurizing position and a load from a square range in which a position range and a load range are specified by detecting a pressurizing position and a load in a pressing operation are detected. When no point deviates, a "load judgment" that makes the load judgment OK and a zone in which a plurality of the load judgments are continuous are formed as shown in FIG. 20, and the pressurizing position and the load are formed from this zone. When none of the data points consisting of the above deviates, the "zone load determination" that makes the load determination OK, and as shown in FIG. 21, the inlet and outlet of the square are defined, and the pressurization position and load are defined there. There is a "load path determination" in which the load determination is OK when the curve of the time-series data consisting of the above data points passes from the entrance to the exit determined above. All of these are for determining whether or not the pressurization work has been performed correctly.

FIG. 19 shows the state of “load determination”. In the load determination, two positions, "determination start position" and "determination end position", are set, and "upper limit load" and "lower limit load" are set at the two positions, respectively. As shown in FIG. 19, these four points form a quadrangular determination frame. If the data point consisting of the pressurizing position and the load at the time of actual work does not deviate from this determination frame, it is determined to be OK, and if it deviates, it is determined to be NG.

FIG. 20 shows the state of “zone load determination”. In FIG. 20, each of zone 1, zone 2, ... Is the same as the quadrangular determination frame shown in the above "load determination". That is, the "zone load determination" is equivalent to the case where a plurality of "load determinations" are continuous. What is shown in FIG. 20 is expressed as a polygonal line, but it can also be regarded as continuous by taking a section of each zone sufficiently short.

FIG. 21 shows the state of “load path determination”. In the load path determination, the path from where to enter and where to exit from the specified sampling area is used as the determination material. The one shown in FIG. 21 shows an example in which it is determined that the case of entering from the lower side of the area and exiting from the upper side is OK. For example, some patterns can be considered, such as determining that the case of entering from the left side of the area and exiting from the upper side is OK, or the case of entering from the left side and exiting from the lower side is judged to be OK.

Japanese Unexamined Patent Publication No. 2008-137015

However, since all of the above determination methods determine the load by looking at the inlet and the outlet, the flow of the load change, that is, the course of the load change can be determined. There was a problem that there was no point of view to grasp.

Therefore, the present invention has been made in view of the above-mentioned problems, and provides an electric press, a load determination method, and a program for performing load determination according to machining work or load determination that is intuitive and easy for the user to understand. With the goal.

Embodiment 1; In one or more embodiments of the present invention, a detection unit that detects the pressurization position of the pressurization section during pressurization processing and a load value at the pressurization position, and a detection section that detects the pressurization section. A load information storage unit that stores time-series data in which the pressurizing position of the pressurizing portion and the load value at the pressurizing position are associated with each other, and a reference position of the pressurizing portion detected in advance during pressurization processing. At a predetermined data point of a graph formed from a reference load information storage unit that stores reference time-series data corresponding to the reference load value at the reference position and time-series data stored in the load information storage unit. A direction calculation unit for calculating a direction and a direction at a predetermined data point of a graph formed from the reference time series data stored in the reference load information storage unit, and a direction at a predetermined data point of the time series data. And the direction comparison unit for obtaining the difference between the direction at the corresponding data point of the reference time-series data corresponding to the predetermined data point, and at least the predetermined time-series data obtained by the direction comparison unit. We propose an electric press characterized by including a determination unit for determining whether or not the difference between the direction at a data point and the direction at the corresponding data point of the reference time series data is included in a predetermined range. is doing.

Embodiment 2; In one or more embodiments of the present invention, the shape of the graph formed from the time series data is moved in parallel with the position data axial direction regarding the pressurization position or the load data axial direction with respect to the load value. , Corresponding data that identifies the corresponding data point of the reference time series data corresponding to the predetermined data point of the time series data by approximately superimposing on the shape of the graph formed from the reference time series data. We are proposing an electric press equipped with a point identification part.

Embodiment 3; One or more embodiments of the present invention include a distance calculation unit for obtaining a distance between the predetermined data point of the time series data and the corresponding data point of the reference time series data, and the determination unit. Proposes an electric press that determines whether or not the distance obtained by the distance calculation unit is included in a predetermined range.

Embodiment 4; One or more embodiments of the present invention include a normalization processing unit that normalizes the time-series data and the reference time-series data, and the direction calculation unit is the normalized time. We propose an electric press that calculates the direction of the predetermined data point of the series data and the direction of the normalized reference time series data at the corresponding data point.

Embodiment 5; One or more embodiments of the present invention include the predetermined data points of the time-series data normalized in the normalized processing unit and the reference normalized in the normalized processing unit. A normalized data distance calculation unit for obtaining a distance of time-series data from the corresponding data point is provided, and the determination unit is obtained by the distance and the direction comparison unit obtained by the normalized data distance calculation unit. We are proposing an electric press that determines whether or not the difference in the above-mentioned directions is included in a predetermined range.

Embodiment 6; In one or more embodiments of the present invention, the direction calculation unit uses regression calculation to determine the direction of the time series data at the predetermined data point and the direction of the reference time series data at the corresponding data point. We are proposing an electric press that calculates.

Embodiment 7; In one or more embodiments of the present invention, the normalization processing unit sets the pressurization start position to 0 and the pressurization end position to 1 with respect to the position, and sets the pressurization start load to 0 with respect to the load. We are proposing an electric press that executes a normalization process with a pressurization end load of 1.

Embodiment 8; One or more embodiments of the present invention correspond to the pressurizing position of the pressurizing portion of the electric press and the load value at the pressurizing position at the time of pressurization detected by the detection unit of the electric press. Reference time-series data that associates the load information storage unit that stores the attached time-series data with the reference position of the pressurization unit and the reference load value at the reference position during pressurization processing that was detected in advance by the detection unit. It is a load determination method in a load determination device including a reference load information storage unit, a direction calculation unit, a direction comparison unit, and a determination unit for storing data, and the direction calculation unit stores the data in the load information storage unit. Calculates the direction at a predetermined data point of the graph formed from the time-series data and the direction at the predetermined data point of the graph formed from the reference time-series data stored in the reference load information storage unit. A graph formed from the direction at the predetermined data point of the graph formed from the time-series data and the reference time-series data corresponding to the predetermined data point. The second step of obtaining the difference between the direction at the corresponding data point and the direction at the predetermined data point of the graph formed by the determination unit at least from the time series data obtained by the direction comparison unit. A load characterized by comprising a third step of determining whether or not the difference between the direction at the corresponding data point of the graph formed from the reference time series data and the corresponding data point is included in a predetermined range. We are proposing a judgment method.

Embodiment 9; One or more embodiments of the present invention propose a load determination method in which the electric press includes the load determination device.

Embodiment 10; One or more embodiments of the present invention correspond to the pressurizing position of the pressurizing portion of the electric press and the load value at the pressurizing position at the time of pressurization detected by the detection unit of the electric press. Reference time-series data that associates the load information storage unit that stores the attached time-series data with the reference position of the pressurization unit and the reference load value at the reference position during pressurization processing that was detected in advance by the detection unit. This is a program for causing a computer to execute a load determination method in a load determination device including a reference load information storage unit, a direction calculation unit, a direction comparison unit, and a determination unit for storing data. , The direction at a predetermined data point of the graph formed from the time-series data stored in the load information storage unit, and the predetermined graph formed from the reference time-series data stored in the reference load information storage unit. The first step of calculating the direction at the data point, the direction at the predetermined data point of the graph formed from the time series data, and the reference corresponding to the predetermined data point. The second step of obtaining the difference between the direction at the corresponding data point of the graph formed from the time-series data and the graph formed by the determination unit from at least the time-series data obtained by the direction comparison unit. A third step of determining whether or not the difference between the direction at the predetermined data point and the direction at the corresponding data point of the graph formed from the reference time series data is included in the predetermined range. We are proposing a program to make the computer execute.

11; One or more embodiments of the present invention propose a program in which the motorized press comprises the load determination device and is executed by the computer of the motorized press.

According to one or more embodiments of the present invention, since the load can be determined by the load flow (flow), there is an effect that higher quality machining work can be performed. In addition, since the position data and the load data are normalized and the distance and the direction are obtained, there is an effect that a significant evaluation can be performed. Further, since the load slope value is obtained by regression calculation as the direction, significant data resistant to noise can be obtained, and there is an effect that effective determination can be made based on this data.

It is a figure which shows the structure of the electric press which concerns on 1st Embodiment of this invention. It is a figure which shows the electric structure of the electric press which concerns on 1st Embodiment of this invention. It is a figure which shows typically the method of specifying the corresponding data in the corresponding data point specifying part of the electric press which concerns on 1st Embodiment of this invention. It is a figure which shows the electric structure of the central processing unit which concerns on 1st Embodiment of this invention. It is a figure which illustrates the direction at the corresponding data point of the reference time series data in the load flow determination which concerns on 1st Embodiment of this invention, and the direction at a predetermined data point of the detected time series data. It is a processing flow diagram which concerns on 1st Embodiment of this invention. It is a figure which illustrated the calculation of the direction in 1st Embodiment of this invention. It is a figure which shows the electric structure of the electric press which concerns on 2nd Embodiment of this invention. It is a figure which shows the electric structure of the central processing unit which concerns on 2nd Embodiment of this invention. The direction at the corresponding data point of the reference time series data in the load flow determination according to the second embodiment of the present invention, the direction at the predetermined data point of the detected time series data, and the distance between the corresponding data point and the predetermined data point. It is a figure exemplifying. It is a processing flow diagram which concerns on 2nd Embodiment of this invention. It is a flow chart of the minimum distance point search process in the electric press which concerns on 2nd Embodiment of this invention. It is a figure which conceptually showed the method of distance calculation in the 2nd Embodiment of this invention. It is a figure which shows the effect in the 2nd Embodiment of this invention. It is a figure which shows the electric structure of the electric press which concerns on 3rd Embodiment of this invention. It is a figure which shows the electric structure of the central processing unit which concerns on 3rd Embodiment of this invention. The direction at the corresponding data point of the normalized reference time series data in the load flow determination according to the third embodiment of the present invention, the direction at the predetermined data point of the normalized detected time series data, and the normalized. It is a figure which exemplifies the distance between the corresponding data point and a predetermined data point. It is a processing flow diagram which concerns on 3rd Embodiment of this invention. It is a figure for demonstrating the load determination which concerns on the prior art. It is a figure for demonstrating the zone load determination which concerns on the prior art. It is a figure for demonstrating the load path determination which concerns on the prior art.

<First Embodiment>
Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 7.

<Structure of press equipment>
The structure of the electric press 100 according to the present embodiment will be described with reference to FIG.

As shown in FIG. 1, the press device 100 according to the present embodiment has a press ram 1 that applies a desired pressure to a work W (machining target) by an elevating operation, and an elevating operation (straight line) to the ram 1. It is composed of a ball screw 2 that gives motion), and these are provided in the press main body 3. Further, a servomotor 4 such as an AC servomotor as a drive source is also housed in the head frame of the casing 5 connected to the press main body 3. Then, the drive of the servomotor 4 is transmitted to the ball screw 2 via the pulley and the belt.

As shown in FIG. 1, the ram 1 is formed in a cylindrical body. Specifically, a hollow portion is formed along the axial direction inside the cylindrical main body 1a formed in a cylindrical shape, and the screw shaft 2a of the ball screw 2 can be inserted into the hollow portion. It has become. Further, the nut body 2b of the ball screw 2 is fixed to the end portion of the tubular main body 1a of the ram 1 in the axial length direction.

A strain-causing column 9 is configured to be freely mounted on the tip of the tubular main body 1a, and in reality, the strain-causing column 9 comes into contact with the work W and appropriately applies pressure. .. Further, the strain raising column 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.

A cylindrical guide 6 is provided so as to wrap the outer peripheral side surface of the tubular main body 1a. The tubular guide 6 is fixed in the casing 5, and the ram 1 is configured to be movable up and down along the tubular guide 6.

<Electrical configuration of press equipment>
As shown in FIG. 2, the electric press 100 according to the present embodiment includes a servomotor driver 13, an encoder 14, a circuit unit 15, a drive command pulse generation unit 16, an encoder position counter 17, and a control program storage unit. 21, display unit 22, operation unit 23, temporary storage unit 24, reference load information storage unit 25, load information storage unit 26, determination direction data storage unit 27, corresponding data point identification unit 28, and It is composed of a CPU (central arithmetic processing device) 30.

The control program storage unit 21 stores a control program for the CPU (central processing unit) 30 to control the operation and processing of the entire press device 100. For example, in the present embodiment, not only the main program related to the press work, but also the direction of the time series data stored in the load information storage unit 26 described later at a predetermined data point and the reference stored in the reference load information storage unit 25. Find the difference between the direction at a given data point of a program or time-series data that calculates the direction at a given data point of time-series data and the direction at the corresponding data point of the reference time-series data corresponding to the given data point. A program, a program for determining whether or not the difference between the direction of the obtained time-series data at a predetermined data point and the direction at the corresponding data point of the reference time-series data is included in the predetermined range is stored. The display unit 22 is a display device that displays various types of information. In this embodiment, for example, information such as a determination result is displayed.

The operation unit 23 includes a touch panel, a tact switch, and the like for setting press-fitting conditions and the like. The temporary storage unit 24 stores temporary data. In this embodiment, the obtained position information, load value, and the like are stored.

The reference load information storage unit 25 is a reference time series in which the reference position of the pressurizing unit detected by the circuit unit 15 and the encoder 14 described later and the reference load value at the reference position are associated with each other in advance. Store data. The load information storage unit 26 stores time-series data in which the pressurizing position of the pressurizing unit detected by the circuit unit 15 as the detection unit or the encoder 14 and the load value at the pressurizing position are associated with each other.

The direction at a predetermined data point of the time series data stored in the determination direction data storage unit 27 and the load information storage unit 26 calculated by the direction calculation unit 31 described later, and the reference time stored in the reference load information storage unit 25. Stores the direction of the series data at a predetermined data point.

The corresponding data point identification unit 28 moves the shape of the graph formed from the time series data in parallel with the position data axial direction regarding the pressurization position or the load data axial direction regarding the load value, and the graph formed from the reference time series data. By approximately superimposing on the shape of, the corresponding data point of the reference time-series data corresponding to the predetermined data point of the time-series data is specified. Specifically, as shown in FIG. 3A, when the shape of the graph formed from the reference time series data is shown by a solid line and the shape of the graph formed from the time series data is shown by a dotted line, the corresponding data point is specified. In the case of FIG. 3A, the unit 28 moves the shape of the graph formed from the time series data in parallel in the negative direction of the position data axis so that the two graphs overlap each other at the most points. The shape of the graph formed from the series data is approximately superimposed on the shape of the graph formed from the reference time series data. When this process is executed, it becomes as shown in FIG. 3 (B). Here, when a predetermined data point in the graph formed from the time series data is indicated by a black circle, the point of the graph formed from the reference time series data closest to the black circle is the corresponding data point (FIG. 3). (B) Specified as a positive point). Although the movement in FIG. 3 is illustrated only in the position data axis direction, the movement may be performed in parallel with the load data axis direction.

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 generating column 9, converts the analog signal into a digital signal by the A / D conversion process, and then performs the CPU ( 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 the drive command pulse via the CPU (central processing unit) 30. The signal is output to the servomotor 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 detection unit for detecting the position is for detecting the rotation angle of the servomotor 4, and is used for detecting the position of the ram 1. Further, the information of the encoder 14 gives the position 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, thereby detecting the movement amount of the ram 1.

The CPU (Central Processing Unit) 30 controls the operation of the entire press device 100 according to the control program stored in the control program storage unit 21. In this embodiment, in particular, the process related to the load determination is mainly carried out.

<Electrical configuration of central processing unit>
As shown in FIGS. 4 and 5, the central processing unit 30 according to the present embodiment includes a direction calculation unit 31, a direction comparison unit 32, and a determination unit 33.

As shown in FIG. 5, the direction calculation unit 31 determines the direction of the time-series data stored in the load information storage unit 26 at a predetermined data point and the predetermined time-series data stored in the reference load information storage unit 25. And the direction at the data point of. Specifically, the direction calculation unit 31 performs a regression calculation to indicate the direction of the time series data stored in the load information storage unit 26 at a predetermined data point and the reference time series stored in the reference load information storage unit 25. Calculate the direction at the corresponding data point of the data.

The direction comparison unit 32 corresponds between the direction at a predetermined data point of the time series data calculated by the direction calculation unit 31 shown in FIG. 5 and the reference time series data corresponding to the predetermined data point calculated by the direction calculation unit 31. Find the difference from the direction at the data point.

The determination unit 33 determines whether or not the difference between the direction at the predetermined data point of the time series data obtained by the direction comparison unit 32 and the direction at the corresponding data point of the reference time series data is included in the predetermined range. The determination is made, and the determination result is displayed on the display unit 22.

<Processing of electric press>
The processing of the electric press 100 in this embodiment will be described with reference to FIGS. 6 and 7.

First, the electric press 100 operates the CPU 30 and creates reference time series data as a preparatory step. This is created from the typical position-load time series data when the correct machining work is performed. Actually, normal press working is performed several times, and reference time series data is created based on this data. The created reference time series data is stored in the reference load information storage unit 25.

The electric press 100 operates the CPU 30 and detects, for example, the pressurizing position information obtained from the encoder 14 and the load information obtained from the circuit unit 15 during the pressing operation (step S101). The electric press 100 stores in the load information storage unit 26 time-series data in which the pressurizing position of the pressurizing section detected in step S101 and the load value at the pressurizing position are associated with each other (step S102).

Further, the electric press 100 operates the corresponding data point specifying unit 28 via the CPU 30 to change the shape of the graph formed from the time series data in the position data axial direction regarding the pressurization position or the load data axial direction regarding the load value. By moving them in parallel and approximately superimposing them on the shape of the graph formed from the reference time series data, the corresponding data points of the reference time series data corresponding to the predetermined data points of the time series data are specified (step S103). ).

Next, the electric press 100 operates the direction calculation unit 31 via the CPU 30, and stores the direction at a predetermined data point of the time series data stored in the load information storage unit 26 and the reference load information storage unit 25. The direction at the corresponding data point of the reference time series data is calculated (step S104).

Here, the direction calculation unit 31 calculates the direction at the corresponding data point and the direction at the predetermined data point as a derivative (slope) with respect to the position of the load. In addition, regression calculation is used as the calculation method of this slope. The method of obtaining the direction Qn at the point P _n (X _n , Y _n ) of the reference time series data will be illustrated below.

Here, a method of finding the direction in P _n is exemplified in the eight time series data of P _n , P _n-1 , P _n-2 , ..., P _n-7 shown in the lower figure of FIG. 7. .. Specifically, as shown in the lower figure of FIG. 7, from eight time-series data of P _n , P _n-1 , P _n-2 , ..., P _n-7 , the number 1 is used. The direction is obtained by finding the slope of the regression line.

Table 1 above is an example in which the number of time-series data m is set to m = 8 in Equation 1. In Table 1, the second column Xn-i and the third column Yn-i from the left are time-series data. The bottom row is the calculated value of the addition part of the number 1. Further, in Table 1, the fourth column from the left and the fifth column show each item of the number 1. Substituting this example into Equation 1 and calculating, the slope is about 0.206.

Further, FIG. 7 is a graph showing this data. In FIG. 7, the upper graph is a graph showing the whole, and the lower graph in FIG. 7 is an enlargement of a part having time series data. The straight line is a regression line having a slope calculated by Equation 1. As you can see in the graph below, the time series data is scattered around the obtained regression line. The slope of each point obtained from the reference time series data may be calculated each time, but may be calculated and stored in advance.

Next, the slope of the detected time-series data is obtained as the press work is performed. This calculation method can also be calculated from the slope of the regression line as described above. That is, the slope can be obtained by the same method as that of the number 1 based on the number of time series data.

Next, the direction comparison unit 32 obtains the difference between the direction at the predetermined data point of the time series data and the direction at the corresponding data point of the reference time series data corresponding to the predetermined data point (step S105).

The difference in direction may be obtained as the difference in inclination, but the difference in inclination may be converted into an angle by taking the inverse tangent (arctangent) of the value of the inclination and compared. For example, taking an inverted tangent with an inclination of 0.206 and making an angle, it becomes about 11.65 degrees.

The determination unit 33 determines whether or not the difference between the direction at the predetermined data point of the time series data obtained by the direction comparison unit 32 and the direction at the corresponding data point of the reference time series data is included in the predetermined range. (Step S106). In the above example, the direction of the reference time series data is 11.65 degrees. Therefore, if the determination range is ± 3.00 degrees, the direction of the time series data at a predetermined data point is 8. If it is 65 degrees to 14.65 degrees, it can be judged to be in the normal range. Then, the determination unit 33 displays the determination result on the display unit 22, and ends the series of processing.

As described above, according to the present embodiment, the direction calculation unit 31 stores the direction of the time-series data stored in the load information storage unit 26 at a predetermined data point and the reference load information storage unit 25. The direction of the reference time-series data at a predetermined data point is calculated. The direction comparison unit 32 obtains the difference between the direction at a predetermined data point of the time series data and the direction at the corresponding data point of the reference time series data corresponding to the predetermined data point. The determination unit 33 determines whether or not the difference between the direction at the predetermined data point of the time series data obtained by the direction comparison unit 32 and the direction at the corresponding data point of the reference time series data is included in the predetermined range. judge.
Therefore, since the load can be determined by the load flow (flow), higher quality machining work becomes possible. In addition, since the load slope value is obtained by regression calculation as the direction, significant data resistant to noise can be obtained, and effective determination can be made based on this data.

<Second embodiment>
Hereinafter, the second embodiment of the present invention will be described with reference to FIGS. 8 to 14.

<Electrical configuration of press equipment>
As shown in FIG. 8, the electric press 100A according to the present embodiment includes a servomotor driver 13, an encoder 14, a circuit unit 15, a drive command pulse generation unit 16, an encoder position counter 17, and a control program storage unit. 21, display unit 22, operation unit 23, temporary storage unit 24, reference load information storage unit 25, load information storage unit 26, determination direction data storage unit 27, determination distance data storage unit 29, It is composed of a CPU (central arithmetic processing device) 30A. Since the components having the same reference numerals as those of the first embodiment have the same functions, detailed description thereof will be omitted.

The determination distance data storage unit 29 stores the distance between a predetermined data point of the time series data calculated by the distance calculation unit 34, which will be described later, and a corresponding data point of the reference time series data.

The CPU 30A has a distance calculation function in the distance calculation unit 34 and a determination function in the determination unit 33A, which will be described later.

<Electrical configuration of central processing unit>
As shown in FIG. 9, the central processing unit 30A according to the present embodiment includes a direction calculation unit 31, a direction comparison unit 32, a determination unit 33A, and a distance calculation unit 34. Since the components having the same reference numerals as those of the first embodiment have the same functions, detailed description thereof will be omitted.

The distance calculation unit 34 calculates the distance between a predetermined data point of the time series data shown in FIG. 10 and a corresponding data point of the reference time series data. The determination unit 33A determines whether or not the distance determined by the distance calculation unit 34 and the difference in the direction determined by the direction comparison unit 32 are included in the predetermined range.

<Processing of electric press>
The processing of the electric press 100A in the present embodiment will be described with reference to FIGS. 11 to 13.

First, the electric press 100A operates the CPU 30A and creates reference time series data as a preparatory step. This is created from the typical position-load time series data when the correct machining work is performed. Actually, normal press working is performed several times, and reference time series data is created based on this data. The created reference time series data is stored in the reference load information storage unit 25.

The electric press 100A operates the CPU 30A and detects, for example, the pressurizing position information obtained from the encoder 14 and the load information obtained from the circuit unit 15 during the pressing operation (step S210). The electric press 100A stores in the load information storage unit 26 time-series data in which the pressurizing position of the pressurizing section detected in step S210 and the load value at the pressurizing position are associated with each other (step S220).

The electric press 100A operates the direction calculation unit 31 via the CPU 30A, and the direction at a predetermined data point of the time series data stored in the load information storage unit 26 and the reference time stored in the reference load information storage unit 25. The direction at the corresponding data point of the series data is calculated (step S230). The details of the direction calculation method are the same as those in the first embodiment.

The direction comparison unit 32 obtains the difference between the direction at the predetermined data point of the time series data and the direction at the corresponding data point of the reference time series data corresponding to the predetermined data point (step S240).

The distance calculation unit 34 obtains the distance between a predetermined data point of the time series data and a corresponding data point of the reference time series data (step S250). Specifically, the point closest to the predetermined data point of the time series data (short distance) is searched from the reference time series data string, and that point is set as the corresponding data point. More specifically, as shown in FIG. 13A, the distances between all the data points of the reference time-series data points and the predetermined data points of the time-series data are calculated, and the point where the distance is the minimum is found. .. The method of detecting the point where the distance is the minimum is, for example, comparing the distances in order from the data point of the reference time series data closest to the predetermined data point of the previous time series data, and the point before the distance becomes large. The method you ask for is conceivable.

The distance between the predetermined data point of the time-series data and the data point of the reference time-series data is P _n (X _n , Y _n ) for the data point of the reference time-series data and PR for the predetermined data point of the time- _series data. When ( _{XS, Y R )} is set, it can be calculated using the following equation 2 as an example.

FIG. 13A shows the above distance D _n . 13 (A) is an enlarged part of the left side of FIG. 13 (A) and is shown on the right side of FIG. 13 (A). In FIG. 13A, the data points of the reference time series data are shown, and the distance _closest to the predetermined data point PR of the time series data, that is, the distance calculated by the equation 2 is the smallest P _n . Find a point. Hereinafter, the process of finding the P _n point will be described each time the predetermined data point _PR of the time series data is updated with reference to FIG. 12.

First, the search counter J is set to 1 (step S251). Here, the search counter J counts the reference time series data from 1 to N in subscripts. In the second and subsequent times (step S252) after one round, the search counter J is not initialized, and the process is started from step S253.

The distance calculation unit 34 acquires a predetermined data point PR of the time series data (step _S254 ), calculates the distance between the data point of the reference time series data and the predetermined data point _PR of the time series data, and calculates the distance. The calculated distance is temporarily stored in the determination distance data storage unit 29 as the variable D _n2 . That is, the value in the variable _Dn2 becomes the minimum distance after the processing is completed for all the data points of the reference time series data.

The distance calculation unit 34 confirms whether or not the data point used for calculating the distance is the last data point of the reference time series data (step S256). Here, when the distance calculation unit 34 determines that the data point used for calculating the distance is not the last data point of the reference time series data (“NO” in step S256), the process proceeds to step S257. On the other hand, when the distance calculation unit 34 determines that the data point used for calculating the distance is the last data point of the reference time series data (“YES” in step S256), all the processes are terminated. ..

When the distance calculation unit 34 determines that the data point used for calculating the distance is not the last data point of the reference time series data (“NO” in step S256), the counter value of the search counter is incremented by one. (Step _S257 ), the distance between the data point of the next reference time-series data and the predetermined data point PR of the time-series data is calculated (step S258).

Then, the distance calculation unit 34 determines whether or not the calculated distance is longer than the stored distance (step S259). When the distance calculation unit 34 determines that the calculated distance is longer than the stored distance (“YES” in step S259), the process returns to step S255. On the other hand, when the distance calculation unit 34 determines that the calculated distance is not longer than the stored distance (“NO” in step S259), the counter value of the search counter is decremented by one (step S260). End the process.

As another method for the distance calculation unit 34 to obtain the distance, there is a method shown below. This method is a method of finding a geometrical distance, that is, a method of regarding a reference time-series data as a polygonal line and finding a geometrical distance between a line segment constituting this polygonal line and a predetermined point of the time-series data. Is.

An outline of this method is shown in FIG. The figure on the right side of FIG. 10 is an enlarged view, in which a perpendicular line is drawn from a predetermined point of the time series data to the reference time series data, and the length from the predetermined point of the time series data to the foot of the perpendicular line is referred to as “distance”. It is something to do. Specifically, as shown in FIG. 13 (A), based on the same definition as above, the nth line segment, that is, the line consisting of points P _n and P _{n + 1} with respect to the reference time series data. Draw a perpendicular line from the point _PR every minute.

Here, if the equation of the straight line passing through the two points P _n and P _{n + 1} is the number 3, then since this straight line passes through the two points P _n and P _{n + 1} , the coefficient An is as in the number 4. , B _n , C _n can be obtained.

Then, the equation of the straight line of the number 5 passing through the two points from the number 3 and the number 4 is obtained, and this is transformed, and the geometry of the straight line and the point _PR ( _XS , _YR ) based on this reference time series data is obtained. If the distance is D _n , then D _n can be obtained from the equation 6.

For the perpendicular foot of number 6 (distance D _n ), the perpendicular foot may go out of the line segment formed by the reference time series data. In order to determine whether the foot of this perpendicular line is within the line segment, k of the number 7 is calculated. Here, as shown in FIG. 13B, k is the length of the line segment P _n P _{n + 1} consisting of the data point P _n (X _n , Y _n ) and the data point P _{n + 1} (X _{n + 1} , Y _{n + 1} ). For A and the line segment, a line segment consisting of an intersection point P _k of a perpendicular line from a predetermined data point _{PR (X R, Y R ) and} , for example, a data point P _n (X _n , Y _n ). It shows the ratio of P _n P _k to the length B.

If k obtained in Equation 7 satisfies Equation 8, the foot of the perpendicular line is within the line segment. That is, when the ratio of the length A of the line segment P _n P _{n + 1} to the length B of the line segment P _n P _k does not satisfy the equation 8, the predetermined data points _{PR (XS, Y R ) .} The foot of the perpendicular line from) does not fit in the line segment P _n P _{n + 1} . In that case, the distance _Dn is calculated from the number 2 instead of the number 6.

The coordinates PSn (XSn, YSn) of the foot of the perpendicular line shown in FIG. 10 can be obtained by the following equation 9.

Then, the determination unit 33A determines whether or not the difference between the direction at the predetermined data point of the time series data obtained by the direction comparison unit 32 and the direction at the corresponding data point of the reference time series data is included in the predetermined range. It is determined whether or not the calculated distance is included in the predetermined range (step S270). The determination result is displayed on the display unit 22.

Here, the determination distance may be uniform (determined by the same value everywhere) or may have different values depending on the location (for the position or corresponding to the target normalized data string).

As described above, according to the present embodiment, the direction calculation unit 31 stores the direction of the time-series data stored in the load information storage unit 26 at a predetermined data point and the reference load information storage unit 25. The direction of the reference time-series data at a predetermined data point is calculated. The direction comparison unit 32 obtains the difference between the direction at a predetermined data point of the time series data calculated by the direction calculation unit 31 and the direction at the corresponding data point of the reference time series data corresponding to the predetermined data point. The distance calculation unit 34 calculates the distance between a predetermined data point of the time series data and a corresponding data point of the reference time series data. The determination unit 33A determines whether or not the distance determined by the distance calculation unit 34 and the difference in the direction determined by the direction comparison unit 32 are included in the predetermined range. Therefore, since the load can be determined by the load flow (flow), higher quality machining work becomes possible. In addition, since the load slope value is obtained by regression calculation as the direction, significant data resistant to noise can be obtained, and effective determination can be made based on this data. In addition, since the judgment is made by obtaining the distance and the direction, a significant evaluation can be made. Further, in the example shown in FIG. 14, in the conventional load determination, in order to determine that (1), (2), and (3) are OK, it is necessary to take a width of a position that is OK to some extent. However, if the width of OK is taken, the operation as in (4) will also be OK. On the other hand, according to the present embodiment, even if the width of the distance needs to be widened to some extent, there is no big difference in the directions of (1), (2), and (3), and the range is OK. Can be narrowed, whereby (4) can be determined to be NG.

<Third embodiment>
Hereinafter, the third embodiment of the present invention will be described with reference to FIGS. 15 to 18.

<Electrical configuration of press equipment>
As shown in FIG. 15, the electric press 100B according to the present embodiment includes a servomotor driver 13, an encoder 14, a circuit unit 15, a drive command pulse generation unit 16, an encoder position counter 17, and a control program storage unit. 21, display unit 22, operation unit 23, temporary storage unit 24, reference load information storage unit 25, load information storage unit 26, determination direction data storage unit 27, determination distance data storage unit 29, It is composed of a CPU (central arithmetic processing device) 30B. Since the components having the same reference numerals as those of the first embodiment and the second embodiment have the same functions, detailed description thereof will be omitted.

The CPU 30B has a normalization processing function in the normalization processing unit 35, which will be described later, a distance calculation function in the normalized data distance calculation unit 36, and a determination function in the determination unit 33B.

<Electrical configuration of central processing unit>
As shown in FIG. 16, the central processing unit 30B according to the present embodiment includes a direction calculation unit 31, a direction comparison unit 32, a determination unit 33B, a normalization processing unit 35, and a normalized data distance calculation unit 36. It is composed of and. Since the components having the same reference numerals as those of the first embodiment and the second embodiment have the same functions, detailed description thereof will be omitted.

The normalization processing unit 35 performs a process of normalizing the time-series data stored in the load information storage unit 26 and the reference time-series data stored in the reference load information storage unit 25. Specifically, the normalization process as shown in the left figure of FIG. 17 is executed.

The normalized data distance calculation unit 36 is a distance between a predetermined data point of the time-series data normalized by the normalization processing unit 35 and a corresponding data point of the reference time-series data normalized by the normalization processing unit 35. Is calculated.

The determination unit 33B determines whether or not the distance determined by the normalized data distance calculation unit 36 and the difference in the direction determined by the direction comparison unit 32 are included in the predetermined range.

<Processing of electric press>
The processing of the electric press 100B in this embodiment will be described with reference to FIG.

First, the electric press 100B operates the CPU 30B and creates reference time series data as a preparatory step. This is created from the typical position-load time series data when the correct machining work is performed. Actually, normal press working is performed several times, and reference time series data is created based on this data. The created reference time series data is stored in the reference load information storage unit 25.

The electric press 100B operates the CPU 30B and detects, for example, the pressurizing position information obtained from the encoder 14 and the load information obtained from the circuit unit 15 during the pressing operation (step S301). The electric press 100B stores in the load information storage unit 26 time-series data in which the pressurizing position of the pressurizing section detected in step S210 and the load value at the pressurizing position are associated with each other (step S302).

The electric press 100B operates the normalization processing unit 35 via the CPU 30B to normalize the time-series data stored in the load information storage unit 26 and the reference time-series data stored in the reference load information storage unit 25. Processing is performed (step S303).

The electric press 100B operates the direction calculation unit 31 via the CPU 30B, and stores the direction and the reference load information storage unit 25 at a predetermined data point of the normalized time series data stored in the load information storage unit 26. The direction at the corresponding data point of the normalized reference time series data is calculated (step S304). The details of the direction calculation method are the same as those in the first embodiment.

The direction comparison unit 32 obtains the difference between the direction at a predetermined data point of the normalized time series data and the direction at the corresponding data point of the normalized reference time series data corresponding to the predetermined data point (step S305). ).

The normalized data distance calculation unit 36 obtains the distance between a predetermined data point of the normalized time series data and a corresponding data point of the normalized reference time series data (step S306). The details of the distance calculation method are the same as those in the second embodiment.

In the determination unit 33B, the difference between the direction at the predetermined data point of the normalized time series data obtained by the direction comparison unit 32 and the direction at the corresponding data point of the normalized reference time series data is within a predetermined range. And whether or not the distance between the predetermined data point of the calculated normalized time series data and the corresponding data point of the normalized reference time series data is included in the predetermined range. (Step S307). The determination result is displayed on the display unit 22.

As described above, according to the present embodiment, the normalization processing unit 35 stores the time-series data stored in the load information storage unit 26 and the reference time-series data stored in the reference load information storage unit 25. Performs normalization processing. The normalized data distance calculation unit 36 is a distance between a predetermined data point of the time-series data normalized by the normalization processing unit 35 and a corresponding data point of the reference time-series data normalized by the normalization processing unit 35. Is calculated. The determination unit 33B determines whether or not the distance determined by the normalized data distance calculation unit 36 and the difference in the direction determined by the direction comparison unit 32 are included in the predetermined range. Therefore, since the load can be determined by the load flow (flow), higher quality machining work becomes possible. In addition, since the position data and the load data are normalized and the distance and the direction are obtained, a significant evaluation can be made. Furthermore, since the load slope value is obtained by regression calculation as the direction, significant data resistant to noise can be obtained, and effective determination can be made based on this data.

The electric press of the present invention can be realized by recording the processing of the electric press on a computer system or a computer-readable recording medium, causing the electric press to read the program recorded on the recording medium, and executing the program. can. The computer system or computer referred to here includes hardware such as an OS and peripheral devices.

Further, the "computer system or computer" shall include a homepage providing environment (or display environment) if a WWW (World Wide Web) system is used. Further, the program may be transmitted from a computer system or computer in which this program is stored in a storage device or the like to another computer system or computer via a transmission medium or by a transmission wave in the transmission medium. Here, the "transmission medium" for transmitting a 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 above program may be for realizing a part of the above-mentioned functions. Further, a so-called difference file (difference program) may be used, which can realize the above-mentioned functions in combination with a computer system or a program already recorded in the computer.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs and the like within a range that does not deviate from the gist of the present invention. For example, in the present embodiment, it is exemplified that the determination function is included as a part of the function of the electric press, but the present invention is not limited to this, and the determination device having the determination function may be provided separately from the electric press. Further, the determination function may be provided in the server on the cloud.

13; Servo motor driver 14; Encoder 15; Circuit unit 16; Drive command pulse generator 17; Encoder position counter 21; Control program storage unit 22; Display unit 23; Operation unit 24; Temporary storage unit 25; Reference load information storage unit 26; Load information storage unit 27; Judgment direction data storage unit 29; Judgment distance data storage unit 30; CPU (central arithmetic processing device)
30A; CPU (Central Processing Unit)
30B; CPU (Central Processing Unit)
31; Direction calculation unit 32; Direction comparison unit 33; Judgment unit 33A; Judgment unit 33B; Judgment unit 34; Distance calculation unit 35; Normalization processing unit 36; Normalization data distance calculation unit 100; Electric press 100A; Electric press 100B Electric press

Claims (10)

A detection unit that detects the pressure position of the pressure unit during pressure processing and the load value at the pressure position.
A load information storage unit that stores time-series data in which the pressurization position of the pressurization unit detected by the detection unit and the load value at the pressurization position are associated with each other.
A reference load information storage unit that stores reference time-series data in which a reference position of the pressure unit at the time of pressure processing detected in advance and a reference load value at the reference position are associated with each other.
The direction at a predetermined data point of the graph formed from the time series data stored in the load information storage unit and the predetermined data point of the graph formed from the reference time series data stored in the reference load information storage unit. And the direction calculation unit that calculates the direction in
A direction comparison unit for obtaining the difference between the direction at a predetermined data point of the time-series data and the direction at the corresponding data point of the reference time-series data corresponding to the predetermined data point.
Whether or not the difference between the direction of the time-series data obtained by the direction comparison unit at the predetermined data point and the direction of the reference time-series data at the corresponding data point is included in at least a predetermined range. Judgment unit to determine
The shape of the graph formed from the time series data is moved parallel to the position data axial direction related to the pressurization position or the load data axial direction related to the load value, and is approximated to the shape of the graph formed from the reference time series data. A corresponding data point specifying unit that specifies the corresponding data point of the reference time-series data corresponding to the predetermined data point of the time-series data by superimposing the data.
An electric press characterized by being equipped with. A distance calculation unit for obtaining the distance between the predetermined data point of the time series data and the corresponding data point of the reference time series data is provided.
The electric press according to claim 1 , wherein the determination unit determines whether or not the distance obtained by the distance calculation unit is included in a predetermined range. A normalization processing unit that normalizes the time-series data and the reference time-series data is provided.
The direction calculation unit is characterized by calculating the direction of the predetermined data point of the normalized time series data and the direction of the normalized reference time series data at the corresponding data point. The electric press according to claim 1 or claim 2 . Normalization for obtaining the distance between the predetermined data point of the time-series data normalized by the normalization processing unit and the corresponding data point of the reference time-series data normalized by the normalization processing unit. Data distance calculation unit and
Equipped with
The determination unit is characterized in that it determines whether or not the distance determined by the normalized data distance calculation unit and the difference in the direction determined by the direction comparison unit are included in a predetermined range. The electric press according to claim 3 . Any of claims 1 to 4 , wherein the direction calculation unit calculates the direction of the time-series data at the predetermined data point and the direction of the reference time-series data at the corresponding data point by regression calculation. Or the electric press according to item 1. The normalization processing unit executes a normalization process in which the pressurization start position is set to 0 and the pressurization end position is set to 1 with respect to the position, and the pressurization start load is set to 0 and the pressurization end load is set to 1 with respect to the load. The electric press according to claim 3 or 4 . A load information storage unit that stores time-series data in which the pressurizing position of the pressurizing portion of the electric press and the load value at the pressurizing position at the time of pressurization detected by the detection unit of the electric press are associated with each other, and the above-mentioned A reference load information storage unit, a direction calculation unit, and a reference load information storage unit that stores reference time series data in which the reference position of the pressure unit and the reference load value at the reference position at the time of pressurization processing detected in advance by the detection unit are associated with each other. It is a load determination method in a load determination device including a direction comparison unit, a determination unit, and a corresponding data point identification unit .
The direction calculation unit is formed from a direction at a predetermined data point of a graph formed from time series data stored in the load information storage unit and a reference time series data stored in the reference load information storage unit. The first step of calculating the direction at the predetermined data point of the graph, and
The direction comparison unit includes a direction at the predetermined data point of the graph formed from the time series data and a direction at the corresponding data point of the graph formed from the reference time series data corresponding to the predetermined data point. The second step of finding the difference between
The determination unit is at least at the direction at the predetermined data point of the graph formed from the time series data obtained by the direction comparison unit and the corresponding data point of the graph formed from the reference time series data. A third step of determining whether or not the difference between the direction and the direction is within a predetermined range, and
The corresponding data point identification unit moves the shape of the graph formed from the time-series data in parallel with the position data axis direction regarding the pressurization position or the load data axis direction regarding the load value, and from the reference time-series data. A fourth step of identifying the corresponding data point of the reference time-series data corresponding to the predetermined data point of the time-series data by approximately superimposing it on the shape of the formed graph.
A load determination method comprising. The load determination method according to claim 7 , wherein the electric press includes the load determination device. A load information storage unit that stores time-series data in which the pressurizing position of the pressurizing portion of the electric press and the load value at the pressurizing position at the time of pressurization detected by the detection unit of the electric press are associated with each other, and the above-mentioned A reference load information storage unit, a direction calculation unit, and a reference load information storage unit that stores reference time-series data in which the reference position of the pressure unit and the reference load value at the reference position at the time of pressurization processing detected in advance by the detection unit are associated with each other. It is a program for causing a computer to execute a load determination method in a load determination device including a direction comparison unit, a determination unit, and a corresponding data point identification unit .
The direction calculation unit is formed from a direction at a predetermined data point of a graph formed from time series data stored in the load information storage unit and a reference time series data stored in the reference load information storage unit. The first step of calculating the direction at the predetermined data point of the graph, and
The direction comparison unit includes a direction at the predetermined data point of the graph formed from the time series data and a direction at the corresponding data point of the graph formed from the reference time series data corresponding to the predetermined data point. The second step of finding the difference between
The determination unit is at least at the direction at the predetermined data point of the graph formed from the time series data obtained by the direction comparison unit and the corresponding data point of the graph formed from the reference time series data. A third step of determining whether or not the difference between the direction and the direction is within a predetermined range, and
The corresponding data point identification unit moves the shape of the graph formed from the time-series data in parallel with the position data axis direction regarding the pressurization position or the load data axis direction regarding the load value, and from the reference time-series data. A fourth step of identifying the corresponding data point of the reference time-series data corresponding to the predetermined data point of the time-series data by approximately superimposing it on the shape of the formed graph.
A program that lets your computer run. The program according to claim 9 , wherein the electric press includes the load determination device and is executed by a computer of the electric press.

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