JP4337751B2 - Parts replacement time detection device, parts replacement time detection method, and computer program - Google Patents

Description

  The present invention relates to a part replacement time detection device, a part replacement time detection method, and a computer program for detecting the life of a part of a machine tool such as a lathe or a machining center, and particularly provides an appropriate determination index according to the state of operation of the equipment. The present invention relates to a component replacement timing detection device, a component replacement timing detection method, and a computer program.

  For example, a numerical control device for controlling a machine tool such as a lathe or a machining center controls the operation of the machine tool according to a machining program and performs machining on the workpiece. Machining programs can be stored in the coordinate system using a preparation function (G function, G code), auxiliary function (M function, M code), spindle function (S code), feed function (F code), tool function (T function), etc. It is a program for controlling settings, tool or workpiece movement commands, spindle rotation, etc. and performing machining on the workpiece, and is executed by a computer to control the operation of the machine tool.

  When the operation is controlled by a machining program, a load is applied to a drive system such as a servo motor, a mechanism system that transmits power, and the like, and replacement is necessary depending on the type of parts due to wear, vibration, impact, and the like. Therefore, an appropriate index for specifying the replacement time of parts is required.

For example, in Patent Document 1, the moving distance of the moving body for each moving axis for moving the moving body of the machine tool is calculated, the accumulated moving distance for each moving axis is calculated, and the accumulated moving distance is the limit value of the accumulated moving distance. A moving axis monitoring device that outputs a warning signal when a limit moving distance is exceeded is disclosed.
JP 2003-271213 A

  In the conventional moving axis monitoring device disclosed in the above-mentioned Patent Document 1, it is determined whether or not a part needs to be replaced based on whether or not the cumulative value of the moving distance of tools, workpieces, etc. has reached a predetermined value. Therefore, it is considered to be appropriate as an index for determining the necessity of parts replacement due to wear. However, it is not only the wear that affects the durability of parts, but it is also assumed that the durability will be impaired in the same way as when worn for a long time due to vibration, impact, etc. There was a problem that it was not possible to judge the necessity of parts replacement in consideration.

  Also, depending on the type of parts, it is more appropriate to judge the necessity of parts replacement based on the degree of wear, and it is more suitable to judge the necessity of parts replacement based on the frequency of vibration, impact, etc. Parts. Therefore, when it is more suitable to judge the necessity of parts replacement based on the frequency of vibration, shock, etc. In spite of this, there is a risk that the replacement time may be inadvertently delayed, or conversely, there is a possibility that the replacement time will be excessively determined as it is determined that it is the replacement time even though there is no need for replacement yet. There was a problem.

  The present invention has been made in view of such circumstances, and a component replacement timing detection device and a component replacement timing capable of detecting the replacement timing of components in consideration of not only the degree of wear but also vibration, impact, etc. An object is to provide a detection method and a computer program.

  In order to achieve the above object, a component replacement time detection device according to a first aspect of the present invention is a component replacement time detection device that detects a replacement time of a component that constitutes a device whose operation is numerically controlled according to a machining program. A plurality of speed detection means for detecting the operation speed for each part, and an arithmetic processing unit for calculating whether or not it is a replacement time for each part based on the operation speed for each part detected by the speed detection means, The arithmetic processing device includes: a differential value calculating unit that calculates a differential value of an operating speed for each part detected by the speed detecting unit at a constant time interval; a differential value integrating unit that integrates the calculated differential value; A first determination means for determining whether or not the accumulated differential value has reached a predetermined value; and when the first determination means determines that the accumulated differential value of a predetermined part has reached a predetermined value, The parts And an outputting means for outputting the effect that the replacement timing.

  According to a second aspect of the present invention, there is provided the component replacement timing detection device according to the first aspect, wherein the arithmetic processing unit calculates a counter and a second derivative value of the operation speed for each component detected by the speed detection means at a constant time interval. A secondary differential value calculating means for calculating, a second determining means for determining whether or not the calculated secondary differential value exceeds a predetermined value, and the secondary differential value is determined to be a predetermined value by the second determining means. When it is determined that the counter value has been exceeded, the counting means for counting the counter, the third determining means for determining whether or not the counter value of the counter has reached a predetermined value, and the third determining means reaches the predetermined value. And output means for outputting that it is time to replace the component when it is determined.

  According to a third aspect of the present invention, there is provided a part replacement time detection method for detecting a replacement time of a part constituting a device whose operation is numerically controlled according to a machining program. The differential value of the operation speed for each part detected by a plurality of speed detection means for detecting the value is calculated at regular time intervals, the calculated differential values are integrated, and whether the differential value integrated for each part has reached a predetermined value When it is determined that the accumulated differential value of a predetermined part has reached a predetermined value, the fact that it is time to replace the part is output.

  The component replacement timing detection method according to a fourth aspect of the present invention includes the counter according to the third aspect of the present invention, and calculates a second derivative value of the operation speed for each part detected by the speed detection means at a constant time interval. It is determined whether or not the secondary differential value exceeds a predetermined value. When it is determined that the secondary differential value exceeds the predetermined value, the counter is counted, and whether or not the counter value of the counter has reached the predetermined value. When it is determined that the predetermined value has been reached, a message indicating that it is time to replace the part is output.

  A computer program according to a fifth aspect of the present invention is a computer program that can be executed by a part replacement time detection device that detects a replacement time of a part constituting a device whose operation is numerically controlled according to a machining program. The time detection device includes a differential value calculating means for calculating a differential value of the operation speed for each part detected by the speed detecting means at a certain time interval, a differential value integrating means for integrating the calculated differential values, and a differential integrated for each part. When the first determination means for determining whether or not the value has reached a predetermined value and the first determination means determine that the accumulated differential value of the predetermined part has reached the predetermined value, It is made to function as an output means which outputs that it is a replacement time.

  The computer program according to a sixth aspect of the present invention is the computer program according to the fifth aspect, wherein the component replacement time detection device calculates a second derivative of the operation speed for each part detected by the speed detection means at a constant time interval. The differential value calculating means, the second determining means for determining whether or not the calculated secondary differential value exceeds a predetermined value, and when the second differential means determines that the secondary differential value exceeds the predetermined value, A counting means for counting the counter, a third determining means for determining whether or not the counter value of the counter has reached a predetermined value, and when the third determining means determines that the predetermined value has been reached, It is made to function as an output means which outputs that it is the replacement time of parts.

  In the first invention, the third invention, and the fifth invention, the operation speed for each part constituting the device is detected, the differential value of the detected operation speed for each part is calculated at a constant time interval, and the calculated differential value is calculated. Accumulate. When the differential value integrated for each part reaches a predetermined value, the fact that it is time to replace the part is output. As a result, the acceleration at a certain time interval can be obtained as a differential value of the speed, and since the acceleration is a physical quantity proportional to the load (force, torque) applied to the component, the cumulative value of the acceleration is a constant upper limit value. When it is determined that it is time to replace the component, it is possible to determine the necessity of component replacement based on the frequency of vibration, impact, and the like. Therefore, it is possible to prevent the replacement timing of the components from being delayed or excessively replacing the components.

  In the second invention, the fourth invention, and the sixth invention, the secondary differential value of the operation speed for each part detected by the speed detection means is calculated at a constant time interval, and the calculated secondary differential value exceeds a predetermined value. In this case, the number of times that the secondary differential value has exceeded a predetermined value is counted, and when the number of times that the secondary differential value has exceeded the predetermined value has reached the predetermined value, it is output that it is time to replace the part. As a result, the jerk at a constant time interval can be obtained as a second derivative value of the speed, and the jerk is one of the vibration factors of the part. If the number of times exceeds the upper limit value, it is determined that it is time to replace the component, so that it is possible to determine the necessity of component replacement based on the degree of vibration or the like. Therefore, it is possible to prevent the replacement timing of the components from being delayed or excessively replacing the components. When there is no equal acceleration section, the second derivative value is an impulse value, so the number of times that the impact has been applied to the part can also be counted, and the need to replace the part based on the number of impacts, etc. It is also possible to judge.

  According to the present invention, acceleration at a constant time interval can be obtained as a differential value of speed, and since acceleration is a physical quantity proportional to a load (force, torque) applied to the component, the cumulative value of acceleration is constant. When it is determined that it is time to replace the component when the upper limit value is reached, it is possible to determine the necessity of component replacement based on the frequency of vibration, impact, and the like. Therefore, it is possible to prevent the replacement timing of the components from being delayed or excessively replacing the components.

  Further, as the second derivative value of the speed, the jerk at a certain time interval can be obtained. Since the jerk is one of the vibration factors of the part, the obtained jerk is a certain value or more. If it is determined that it is time to replace the part when the number of times exceeds the upper limit value, it is possible to determine the necessity of replacing the part based on the degree of vibration or the like. Therefore, it is possible to prevent the replacement timing of the components from being delayed or excessively replacing the components. Even when there is no equal acceleration section, the second derivative value is an impulse value, so the number of times the part has been impacted can be counted, and parts can be replaced based on the number of impacts, etc. It becomes possible to judge the necessity of

  Hereinafter, the present invention will be described with reference to the drawings illustrating embodiments thereof. FIG. 1 is a block diagram showing a configuration of a component replacement time detection apparatus according to an embodiment of the present invention. A component replacement time detection device 1 according to an embodiment of the present invention includes a plurality of speed detection devices (speed detection means) 2, 2,... That detect an operation speed for each component constituting a machine tool (equipment). , And an arithmetic processing unit 3 that calculates whether or not it is a replacement time for each part based on the operation speed for each part detected by the speed detection unit 2.

  In the present embodiment, the configuration of the device is not particularly limited. For example, a machine tool including a column that supports a spindle on which a tool is mounted may be used, and an XY moving mechanism that can move a table is used. It may be a machine tool provided, a tool changer for exchanging tools, or the like. In addition, the components constituting the equipment include, for example, a ball screw, a nut, a bearing, a guide rail for moving a column, a table, etc. in the X-axis direction and the Y-axis direction, a telescopic cover for covering these, a tool gripping arm of a tool changer, etc. Means.

  The arithmetic processing unit 3 includes at least a CPU (central control unit) 30 as a center, a ROM 31, a RAM 32, a display unit 33, an input unit 34 connected to the CPU 30 via an internal bus 37, and an external speed detection unit 2, 2. ,... Are communicably connected to an external interface 35, an auxiliary storage device 36, and the like.

  The CPU 30 is connected to the above-described hardware units of the numerical control device via the internal bus 37, and controls the above-described hardware units, and also stores a processing program stored in the ROM 31, such as an operation of a machine tool. A program for acquiring the speed and calculating the acceleration and / or jerk, a program for determining whether or not the replacement time for the part has been reached, and the like are executed.

  The ROM 31 is a non-volatile storage medium, and stores, for example, a program for obtaining an operating speed of a machine tool and calculating an acceleration and / or jerk, a program for determining whether or not a part replacement time has been reached, and the like. is doing. The RAM 32 is a non-volatile storage medium such as a flash memory. The RAM 32 is a program for acquiring the operating speed of the machine tool and calculating the acceleration and / or jerk, and a program for determining whether or not the time for replacing parts has been reached. Temporary data generated during execution is stored. These programs can be acquired from an external computer via communication means (not shown) or from a portable storage medium such as a DVD or CD-ROM via the auxiliary storage device 36.

  The display device 33 is a display device such as a liquid crystal display device (LCD) or a display device (CRT) that displays and outputs an image to the user. The detected operation speed differential value for each component, the differential value integrated value, and the component value An indicator or the like indicating whether or not the replacement time has been reached is displayed.

  The input device 34 obtains the operating speed of the machine tool and calculates acceleration and / or jerk, information such as conditions necessary for execution of a program for determining whether or not a part replacement time has been reached, etc. Keyboard, touch panel, etc. The external interface 35 is communicably connected to the speed detection device 2 installed in a plurality of operating parts provided in the machine tool, and receives a detection value.

  The auxiliary storage device 36 uses a portable storage medium 4 such as a CD or DVD, and downloads a program, data, and the like to be processed by the CPU 30 to the RAM 32. It is also possible to write the data processed by the CPU 30 for backup.

  The speed detection device 2 is a speed sensor that can detect a moving speed for each operable part of the machine tool. Of course, it is not limited to a speed sensor that is an external device, but may be an apparatus that extracts and acquires an operation speed specified by a machining program for operating a machine tool.

  Hereinafter, a method of detecting whether or not it is the replacement time for each operable component by the arithmetic processing device 3 provided in the component replacement time detection device 1 having the above-described configuration will be described. FIG. 2 is a flowchart showing one procedure of the replacement time detection process of the CPU 30 of the arithmetic processing unit 3 provided in the component replacement time detection apparatus 1 according to the embodiment of the present invention. Note that the process of FIG. 2 is an interrupt process activated at regular time intervals, for example, every 1 msec.

  In the present embodiment, the speed in the X-axis direction of one working tool provided in the machine tool will be described in order to simplify the description. For example, it is assumed that a column that supports a spindle on which a tool is mounted moves in the X-axis direction. FIG. 3 is a diagram showing an example of a change in speed in the X-axis direction of one working tool provided in the machine tool in time series. FIG. 3A shows a state in which the moving speed of the tool changes in an S-curve shape.

  The CPU 30 of the arithmetic processing device 3 acquires a signal indicating the moving speed of one working tool in the X-axis direction as a signal from the speed detection device 2 via the external interface 35 (step S201). CPU30 calculates a differential value based on the signal which shows the acquired speed (step S202), and adds the calculated differential value to the total value L (step S203). Note that step S202 functions as a differential value calculation unit, and step S203 functions as a differential value integration unit.

  Since the calculated differential value is the acceleration of the working tool, it has an equivalent relationship with the torque, external force, etc. applied to the tool. FIG. 3B shows a time change of the calculated differential value, and shows that torque, an external force and the like that change such a time change are applied to the operating tool. Therefore, the cumulative value L of the differential value is equivalent to the total of torque, external force, etc. applied to the working tool, and is one index for measuring the durability of the parts constituting the working tool. It should be noted that initialization of the cumulative value L of the differential value may be performed at the first start-up or when parts are replaced.

  The CPU 30 determines whether or not the cumulative value L has exceeded a predetermined value (step S204). When the CPU 30 determines that the cumulative value L is within the predetermined value (step S204: NO), the CPU 30 It is determined that it is not time to replace the parts used in the above, and the above-described interrupt processing is terminated, and a standby state for starting interrupt processing at the next timing is entered. Note that step S204 functions as a first determination unit.

  FIG. 4 is a diagram illustrating an example of a table indicating the upper limit value of the accumulated acceleration value L. As illustrated in FIG. Whether or not it is time to replace the part is determined depending on whether or not the cumulative value L exceeds the upper limit value shown in FIG. 4 for each part constituting the device.

  When the CPU 30 determines that the cumulative value L has exceeded the predetermined value (step S204: YES), the CPU 30 determines that it is time to replace the part used in the tool, and displays a warning signal indicating that. The data is output to the device 33 (step S205). The display device 33 that has received the warning signal notifies the operator that the part is in the replacement period by luminance inversion display, red display, or the like. Note that step S205 functions as output means.

  Further, as an index for measuring the durability of the parts constituting the working tool, an additional speed obtained by further differentiating the acceleration (secondary derivative) may be used. The jerk is equivalent to the impact force on the working tool, and by counting the number of times the impact force of a certain value or more is applied, it is possible to determine the replacement time of the parts based on the impact. FIG. 3C shows the time change of the calculated secondary differential value, and shows that such an impact force is applied to the operating tool.

  FIG. 5 is a flowchart showing another procedure of the replacement time detection process of CPU 30 of arithmetic processing unit 3 provided in component replacement time detection apparatus 1 according to the embodiment of the present invention. The process of FIG. 5 is an interrupt process that is activated at regular time intervals, for example, every 1 msec.

  The CPU 30 of the arithmetic processing device 3 acquires a signal indicating the moving speed of one working tool in the X-axis direction as a signal from the speed detection device 2 via the external interface 35 (step S501). CPU30 calculates a secondary differential value based on the signal which shows the acquired speed (step S502), and judges whether the calculated secondary differential value exceeds predetermined value (step S503). Step S502 functions as a secondary differential value calculation unit, and step S503 functions as a second determination unit.

  When the CPU 30 determines that the secondary differential value is within the predetermined value (step S503: NO), the CPU 30 ends the above-described interrupt processing without counting the counter, and starts the interrupt processing at the next timing. It will be in the standby state.

  When the CPU 30 determines that the secondary differential value has exceeded a predetermined value (step S503: YES), the CPU 30 counts the counter, for example, increments the counter accumulated value M by 1 (step S504), and the counter accumulated value M It is determined whether or not exceeds a predetermined value (step S505). When the CPU 30 determines that the cumulative value M of the counter is equal to or less than the predetermined value (step S505: NO), the CPU 30 ends the above-described interrupt processing and enters a standby state for starting interrupt processing at the next timing. Step S504 functions as a counting unit, and step S505 functions as a third determination unit.

  FIG. 6 is a diagram illustrating an example of a table indicating the upper limit value of the cumulative number of times when the jerk (secondary differential value) exceeds a predetermined upper limit value. Whether or not it is time to replace the part is determined depending on whether or not the cumulative value M of the counter exceeds the number of times shown in FIG. 6 for each part constituting the device.

  When the CPU 30 determines that the counter value has exceeded the predetermined value (step S505: YES), the CPU 30 determines that it is time to replace the parts used in the tool, and displays a warning signal indicating that fact. The data is output to the device 33 (step S506). The display device 33 that has received the warning signal notifies the operator that the component has reached the replacement time by means of a reverse luminance display, a red display, or the like. Note that step S506 functions as an output unit.

  By performing the above-described processing, even when the speed changes as shown in FIG. 6, for example, it is possible to reliably detect the part replacement time. FIG. 7 is a diagram showing another example of a change in speed in the X-axis direction of one working tool provided in the machine tool in time series.

  Fig.7 (a) has shown the state from which the moving speed of a tool changes to trapezoid shape. In this case, the acceleration (primary differential value) of the working tool is a constant value as shown in FIG. 7 (b), and the jerk (secondary differential value) of the working tool is an impulse value as shown in FIG. 7 (c). It becomes. Therefore, even when the jerk is an impulse value, the number of times exceeding the predetermined value can be easily counted by the counter, and the replacement time corresponding to the impact load can be detected.

  Note that the counting of the counter is not limited to incrementing by 1 from 0, but may be performed by setting an upper limit value of the cumulative value M and decrementing by 1 when initializing. Further, the initialization of the cumulative value M of the counter suffices to be executed at the first startup or at the time of parts replacement.

  By performing the processing described above in the Y-axis direction and the Z-axis direction, it is possible to detect an appropriate replacement time for the part of the working tool. Therefore, it is possible to detect an appropriate replacement time for the working tool in which the speed detection device 2 is installed.

  Note that, as in the present embodiment, the present invention is not limited to calculating acceleration and jerk for each of the X axis, Y axis, and Z axis. The jerk may be calculated. This is because, depending on the arrangement of parts, an impact load may be applied only in the Z-axis direction, or an impact load may be applied from each of the three axes.

  As described above, according to the present embodiment, the acceleration at a constant time interval can be obtained as the differential value of the speed, and the acceleration is a physical quantity proportional to the load (force, torque) applied to the component. When it is determined that it is time to replace the component when the cumulative acceleration value reaches a certain upper limit value, it is possible to determine the necessity of component replacement based on the frequency of vibration, impact, and the like. Therefore, it is possible to prevent the replacement timing of the components from being delayed or excessively replacing the components.

  Further, as the second derivative value of the speed, the jerk at a certain time interval can be obtained. Since the jerk is one of the vibration factors of the part, the obtained jerk is a certain value or more. If it is determined that it is time to replace the part when the number of times exceeds the upper limit value, it is possible to determine the necessity of replacing the part based on the degree of vibration or the like. Therefore, it is possible to prevent the replacement timing of the components from being delayed or excessively replacing the components. Even when there is no equal acceleration section, the second derivative value is an impulse value, so the number of times the part has been impacted can be counted, and parts can be replaced based on the number of impacts, etc. It becomes possible to judge the necessity of

  In the present invention, the above-described method for determining the part replacement time based on the accumulated acceleration value L and the method for determining the part replacement time based on the jerk count value may be used independently. In combination, when the replacement time is reached early, a signal indicating that the replacement time is reached may be output. The present invention is not limited to the above-described embodiments, and can be implemented in various forms without departing from the gist of the present invention.

It is a block diagram which shows the structure of the components replacement time detection apparatus which concerns on embodiment of this invention. It is a flowchart which shows one procedure of the replacement time detection process of CPU of the arithmetic processing unit with which the component replacement time detection apparatus which concerns on embodiment of this invention is equipped. It is a figure which shows an example of the change of the speed of the X-axis direction of one working tool with which a machine tool is equipped in time series. It is a figure which shows an example of the table which shows the upper limit of the cumulative value L of acceleration. It is a flowchart which shows the other procedure of the replacement time detection process of CPU of the arithmetic processing unit with which the component replacement time detection apparatus which concerns on embodiment of this invention is equipped. It is a figure which shows an example of the table which shows the upper limit of the frequency | count of accumulation in which jerk (secondary differential value) exceeded the predetermined upper limit. It is a figure which shows the other example of the change of the speed of the X-axis direction of one working tool with which a machine tool is equipped in time series.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Parts replacement time detection apparatus 2 Speed detection apparatus 3 Arithmetic processing apparatus 4 Portable storage medium 30 CPU
31 ROM
32 RAM
33 Display device 34 Input device 35 External interface 36 Auxiliary storage device

Claims (6)

In the part replacement time detection device that detects the replacement time of the parts that make up the equipment whose operation is numerically controlled according to the machining program,
A plurality of speed detecting means for detecting the operating speed of each component constituting the device;
An arithmetic processing unit that calculates whether or not it is a replacement time for each part based on the operation speed for each part detected by the speed detection unit;
The arithmetic processing unit includes:
Differential value calculating means for calculating the differential value of the operation speed for each part detected by the speed detecting means at a constant time interval;
Differential value integration means for integrating the calculated differential value;
First determination means for determining whether or not a differential value integrated for each part has reached a predetermined value;
A component replacement comprising: output means for outputting that it is time to replace the component when the first determination unit determines that the accumulated differential value of the predetermined component has reached a predetermined value; Time detection device. The arithmetic processing unit includes:
A counter,
Secondary differential value calculating means for calculating the secondary differential value of the operation speed for each part detected by the speed detecting means at a constant time interval;
Second determination means for determining whether or not the calculated secondary differential value exceeds a predetermined value;
When the second determination means determines that the secondary differential value exceeds a predetermined value, the counting means for counting the counter;
Third determination means for determining whether the counter value of the counter has reached a predetermined value;
2. The component replacement timing detection apparatus according to claim 1, further comprising an output unit that outputs that the replacement timing of the component is reached when the third determination unit determines that the predetermined value has been reached. In the part replacement time detection method for detecting the replacement time of the parts constituting the equipment whose operation is numerically controlled according to the machining program,
The differential value of the operation speed for each part detected by a plurality of speed detection means for detecting the operation speed for each part constituting the device is calculated at regular time intervals.
Accumulate the calculated differential value,
Determine whether the differential value accumulated for each part has reached a predetermined value,
A component replacement time detection method that outputs that it is the replacement time of a part when it is determined that the integrated differential value of the predetermined part has reached a predetermined value. With a counter,
A second derivative value of the operation speed for each part detected by the speed detection means is calculated at regular time intervals,
Determine whether the calculated second derivative value exceeds a predetermined value,
When it is determined that the secondary differential value exceeds a predetermined value, the counter is counted,
Determine whether the counter value of the counter has reached a predetermined value,
4. The component replacement timing detection method according to claim 3, wherein when it is determined that the predetermined value has been reached, a message indicating that it is the replacement timing of the component is output. In a computer program that can be executed by a part replacement time detection device that detects the replacement time of parts constituting a device whose operation is numerically controlled according to a machining program,
The parts replacement time detection device,
Differential value calculation means for calculating the differential value of the operation speed for each component detected by the speed detection means at a constant time interval;
Differential value integration means for integrating the calculated differential value;
First determination means for determining whether or not a differential value integrated for each part has reached a predetermined value, and the first determination means determines that the differential value integrated for a predetermined part has reached a predetermined value If so, a computer program that functions as an output means for outputting that it is time to replace the component. The parts replacement time detection device,
Secondary differential value calculating means for calculating the secondary differential value of the operation speed for each part detected by the speed detecting means at a constant time interval;
Second determination means for determining whether or not the calculated secondary differential value exceeds a predetermined value;
Counting means for counting the counter when the second judging means judges that the secondary differential value exceeds a predetermined value;
Third determination means for determining whether or not the counter value of the counter has reached a predetermined value, and when the third determination means determines that the predetermined value has been reached, it is time to replace the part. 6. The computer program according to claim 5, wherein the computer program functions as output means for outputting.

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