Numerical control device and computer-readable storage medium
The numerical control device addresses the issue of unexpected energy input in non-contact processing by monitoring and controlling cumulative energy values, preventing excessive application and reducing accident risks without additional hardware.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- FANUC LTD
- Filing Date
- 2024-11-14
- Publication Date
- 2026-05-21
Smart Images
Figure JP2024040414_21052026_PF_FP_ABST
Abstract
Description
Numerical control device and computer-readable storage medium
[0001] The present disclosure relates to a numerical control device and a computer-readable storage medium.
[0002] Non-contact processing machines include laser processing, plasma processing, gas processing, water jet processing, etc. In non-contact processing, energy is applied to the workpiece through media such as light, plasma, gas, water, etc. Some conventional non-contact processing machines monitor the output power and manage the output power. For example, Patent Document 1.
[0003] Japanese Patent Application Laid-Open No. 2020-46390
[0004] In non-contact processing, energy is applied to an object through a medium. When the medium contacts the object, the energy of the medium is applied to the object. Input of energy beyond what is expected or unexpected contact between the medium and the object may lead to damage to the object.
[0005] In the field of non-contact processing, it is desired to avoid unexpected breakage and damage.
[0006] The numerical control device according to the present disclosure includes a position acquisition unit that acquires the actual position of the processing point of a non-contact processing machine, an output value acquisition unit that acquires the output energy value of non-contact processing at the processing point, an input energy calculation unit that calculates the cumulative value of the output energy value input to a certain position, a threshold acquisition unit that acquires the threshold value of the output energy value input to a certain position, and a determination unit that determines whether the output energy value input to a certain position exceeds the threshold value of that position.
[0007] It is a block diagram of a numerical control device. It is a diagram showing an example of a grid. It is a diagram for explaining a method of calculating the cumulative energy value. It is a diagram visually representing the cumulative energy value for each grid. It is a diagram visually representing the cumulative energy value per unit length at a certain position. It is a diagram for explaining an example of the passage of time. It is a diagram for explaining the hardware configuration of a numerical control device.
[0008] Embodiments of this disclosure will be described below with reference to the drawings. In the following description, components having the same or similar functions will be denoted by the same reference numerals. Duplication of these components may be omitted.
[0009] In this application, "based on XX" means "based on at least XX," and includes cases where it is based on another element in addition to XX. Furthermore, "based on XX" is not limited to cases where XX is used directly, but also includes cases where it is based on something that has been calculated or processed. "XX" is any element (for example, any information).
[0010] Figure 1 is a block diagram of the numerical control device 100. The numerical control device 100 includes a position acquisition unit 11, an output value acquisition unit 12, an input energy calculation unit 13, a workpiece shape acquisition unit 14, a material acquisition unit 15, a threshold acquisition unit 16, a determination unit 17, and an output unit 18.
[0011] The position acquisition unit 11 acquires the actual position of the machining point of the non-contact machining machine. Acquiring the actual position is an existing technology. The actual position of the machining point can be acquired from the actual position of the feed axis, etc. The frequency of acquiring the position of the machining point is determined by the acquisition cycle.
[0012] The output value acquisition unit 12 acquires the output energy value of the non-contact machining at the machining point. The output energy value may be a theoretical value calculated based on the machining program or NC data, or it may be an actual value obtained from the non-contact machining machine.
[0013] The input energy calculation unit 13 calculates the cumulative value of the output energy input to a certain location (point, length, range, etc.). Two methods for calculating the energy value are shown below.
[0014] [First Energy Value Calculation Method] In the first energy value calculation method, a predetermined range is defined on the surface used as a reference for non-contact machining (for example, the machining surface), and the cumulative value of the output energy input into that range is calculated. In this embodiment, the machining surface is divided into a grid, and the cumulative value of the output energy input into each grid is calculated. An example of a grid is shown in Figure 2. The star-shaped solid lines represent the machining pattern. The shape of the grid in Figure 2 is a square. The size and shape of the grid are not particularly limited, but the size of the grid is preferably an integer multiple of the minimum movement unit of the acquisition cycle for acquiring the position of the machining point. Making it an integer multiple of the minimum movement unit reduces the processing load. Note that while a larger number of grids improves accuracy, it also increases the processing load. The size and number of grids may be set by default, set by the user, or calculated automatically.
[0015] The input energy calculation unit 13 calculates the cumulative value of the output energy input to the grid (referred to as the cumulative energy value). The method for calculating the cumulative energy value will be explained with reference to Figure 3. In Figure 3, the vertical axis represents the output energy value of non-contact processing, and the horizontal axis represents time. The input energy calculation unit 13 determines the grid that the processing point passes through and calculates the product of the time the processing point stays in the grid and the output energy value input to the processing point. This product is the cumulative energy value. In the example in Figure 3, at a certain time T1, the processing point reaches grid A and passes through grid A for a period of 4 cycles of the position acquisition cycle. After that, the processing point leaves grid A and moves to another grid, and at time T2, it re-enters grid A and passes through grid A for a period of 6 cycles of the position acquisition cycle. If the output energy value in each position acquisition cycle is Pi (1 ≤ i ≤ N) [W], the number of position acquisition cycles included in the period in which the processing point stays in the grid is N, and the time of the position acquisition cycle is T [s], then the cumulative energy value E [J] in each grid is expressed as follows.
[0016]
[0017] Figure 4 is a visual representation of the cumulative energy values for each grid. The cumulative energy values for P1 to P31 are calculated for each grid that the processing point passes through. The cumulative energy value of each grid is compared with a threshold value, which will be described later.
[0018] [Second Energy Value Calculation Method] The second energy value calculation method is a method for calculating the cumulative energy value per unit length at a certain position. The velocity of the processing point is used to calculate the cumulative energy value per unit length. The velocity of the processing point can be calculated from the position information and the acquisition period. The input energy calculation unit 13 divides the output energy value at a certain position by the velocity of the processing point at that position to calculate the cumulative energy value per unit length at that point.
[0019] Figure 5 visually represents the cumulative energy value per unit length at a given location. Cumulative energy values P1 to P17 per unit length are calculated at multiple locations. The cumulative energy value per unit length at each location is compared with a threshold value, which will be described later.
[0020] [Exclusion or reduction of energy values after a predetermined time has elapsed] In calculating the cumulative energy value, energy values after a predetermined time has elapsed since energy input may be excluded or gradually reduced. An example of time elapsed will be explained with reference to Figure 6. Consider the trajectory of the machining point, starting from point B, moving in direction a, and then arriving back at point B from direction b. When the machining point moves along such a trajectory, a long time may have elapsed between the time the machining point leaves point B and the time it returns to point B. In that case, the energy at the time of departure from point B will have disappeared or decreased by the time the machining point returns to point B. The input energy calculation unit 13 stores the time at which the machining point was passed and excludes or gradually reduces the energy at the position after a predetermined time has elapsed since energy input.
[0021] The workpiece shape acquisition unit 14 acquires the shape of the workpiece. The workpiece shape includes at least the thickness of the workpiece. The material acquisition unit 15 acquires the material of the workpiece. Information such as the shape and material of the workpiece is either stored in advance by the numerical control device 100 or acquired by the numerical control device 100 from an external storage device, including the cloud.
[0022] The threshold acquisition unit 16 acquires a threshold value for the output energy input at a certain position. The method of acquiring the threshold is not particularly limited. A fixed threshold may be prepared, or it may be acquired from an external source via a network or storage medium. It may also be set manually by the operator of the numerical control device 100. The threshold acquisition unit 16 may change the acquired threshold according to the workpiece shape or material of the workpiece.
[0023] The determination unit 17 determines whether the energy input to a certain position exceeds the threshold for that position. When determining for each grid, the determination unit 17 compares the cumulative energy value of the grid including the processing point with the threshold. If the cumulative energy value exceeds the threshold, the determination unit 17 determines that excessive energy has been input to a certain area. When determining based on the energy value per unit length, when the processing point passes through a certain point or approaches a certain point, the determination unit 17 compares the input energy per unit length at that point with the threshold. If the input energy per unit length exceeds the threshold, the determination unit 17 determines that excessive energy has been input at that position.
[0024] The output unit 18 notifies the user of the numerical control device 100 that excessive energy has been input, using sound, a screen, a lamp, etc. The means of outputting the notification are not particularly limited; it is sufficient if the user can sense the abnormality. The output unit 18 not only notifies the user of the abnormality but also cuts off the energy input. This prevents excessive energy input.
[0025] As described above, the numerical control device 100 of this embodiment is a numerical control device 100 that controls a non-contact machining machine, and acquires the actual position of the machining point during machining and the energy value applied to that position, and determines whether or not excessive energy has been applied to that position. Excessive energy application can occur, for example, due to an unexpected machine stop or a decrease in feed rate. If the machine stops or the feed rate decreases, energy will continue to be applied to a specific area. Excessive energy application can also occur at the end of machining. If energy continues to be applied even though machining has ended due to a machine failure, energy will continue to be applied to the end point of machining.
[0026] Areas where energy is being injected experience concentrated heat, which can lead to accidents such as fires or machine damage. Unexpected energy output can also cause accidents. For example, the laser of a laser processing machine is invisible, so operators may come into contact with it without realizing it. Also, if energy penetrates the workpiece, the medium may pass through the hole, injecting energy into unexpected locations and potentially damaging the machine.
[0027] The numerical control device 100 solves this problem through software. While it is possible to avoid danger by measuring the laser output and the temperature of the processing surface with sensors, adding new mechanisms to existing non-contact processing machines is costly and time-consuming. It may also be impossible to add new mechanisms to existing non-contact processing machines. The numerical control device 100 of this embodiment can easily avoid excessive energy input without adding any new mechanisms.
[0028] The hardware configuration of the numerical control device 100 to which this disclosure is applied will be described below. Figure 7 is a hardware configuration diagram of the numerical control device 100. As shown in Figure 7, the numerical control device 100 includes a CPU 111 that controls the numerical control device 100 as a whole, a ROM 112 that records programs and data, and a RAM 113 for temporarily expanding data. The CPU 111 reads the system program recorded in the ROM 112 via the bus.
[0029] The non-volatile memory 114 is backed up, for example, by a battery (not shown), so that its stored state is maintained even when the power to the numerical control device 100 is turned off. The non-volatile memory 114 stores various data, such as programs read from external devices 120 via interfaces 115, 118, and 119, and operation inputs entered via input devices 20. The non-volatile memory 114 may also store programs and data for executing the numerical control device 100 of this embodiment.
[0030] Interface 115 is an interface for connecting the numerical control unit 100 to an external device 120 such as an adapter. Programs and various parameters are read from the external device 120. Interface 118 is an interface for connecting the numerical control unit 100 to a display device 30 such as a liquid crystal display. The display device 30 displays data read into memory, data obtained as a result of executing programs, etc. Interface 119 is an interface for connecting the numerical control unit 100 to an input device 20 such as a keyboard or pointing device. The input device 20 passes commands, data, etc. based on operator operations to the CPU 111 via interface 119.
[0031] While embodiments of this disclosure have been described in detail above, this disclosure is not limited to the individual embodiments described above. These embodiments can be added, replaced, modified, partially deleted, etc., in any way that does not depart from the spirit of the invention or from the idea and intent of this disclosure derived from the claims and their equivalents. For example, the order of operations and processes in the embodiments described above are shown as examples only and are not limited thereto. The same applies when numerical values or mathematical formulas are used in the description of the embodiments described above.
[0032] The following are annotations relating to embodiments of the present disclosure. (Annotation 1) A numerical control device (100) according to one aspect of the present disclosure includes: a position acquisition unit (11) that acquires the actual position of a processing point of a non-contact processing machine; an output value acquisition unit (12) that acquires the output energy value of the non-contact processing at the processing point; an input energy calculation unit (13) that calculates the cumulative value of the output energy value input at a certain position; a threshold acquisition unit (16) that acquires a threshold value of the output energy value input at a certain position; and a determination unit (17) that determines whether the output energy value input at a certain position exceeds the threshold value at that position. (Annotation 2) The input energy calculation unit (13) defines a predetermined range on the surface used as a reference for the non-contact processing and calculates the cumulative value of the output energy value input into that range. (Annotation 3) The predetermined range is a grid. (Annotation 4) The predetermined range is determined based on the minimum movement unit of the processing point. (Annotation 5) The input energy calculation unit (13) calculates the cumulative energy value per unit length at a certain position. (Note 6) The input energy calculation unit (13) calculates the cumulative energy value per unit length by dividing the output energy at a certain position by the speed of the processing point at that position. (Note 7) The numerical control device (100) includes a work shape acquisition unit (14) that acquires the shape of the workpiece, and the threshold acquisition unit (16) changes the threshold according to the shape of the workpiece. (Note 8) The numerical control device (100) includes a material acquisition unit (15) that acquires the material of the workpiece, and the threshold acquisition unit (16) changes the threshold according to the material of the workpiece. (Note 9) The input energy calculation unit (13) excludes energy values from the accumulation target or gradually reduces the accumulated energy value according to the elapsed time after energy input. (Note 10) The numerical control device (100) includes an output unit (18) that outputs the determination result of the determination unit (17) by at least one of a signal or a screen display.(Note 11) A computer-readable storage medium (112, 113, 114) according to one aspect of the present disclosure records a program that causes a computer (111) to operate as: a position acquisition unit (11) that acquires the actual position of a processing point of a non-contact processing machine; an output value acquisition unit (12) that acquires the output energy value of non-contact processing at the processing point; an input energy calculation unit (13) that calculates the cumulative value of the output energy value input at a certain position; a threshold acquisition unit (16) that acquires a threshold value of the output energy value input at a certain position; and a determination unit (17) that determines whether the output energy value input at a certain position exceeds the threshold value at that position.
[0033] 100 Numerical control device 11 Position acquisition unit 12 Output value acquisition unit 13 Input energy calculation unit 14 Workpiece shape acquisition unit 15 Material acquisition unit 16 Threshold acquisition unit 17 Judgment unit 18 Output unit 111 CPU 112 ROM 113 RAM 114 Non-volatile memory
Claims
1. A numerical control device comprising: a position acquisition unit that acquires the actual position of a processing point of a non-contact processing machine; an output value acquisition unit that acquires the output energy value of the non-contact processing at the processing point; an input energy calculation unit that calculates the cumulative value of the output energy value input at a certain position; a threshold acquisition unit that acquires a threshold value of the output energy value input at a certain position; and a determination unit that determines whether or not the output energy value input at a certain position exceeds the threshold value at that position.
2. The numerical control device according to claim 1, wherein the input energy calculation unit defines a predetermined range on the surface to be used as a reference for the non-contact processing and calculates the cumulative value of the output energy values input into that range.
3. The numerical control device according to claim 2, wherein the predetermined range is a grid.
4. The numerical control device according to claim 2, wherein the predetermined range is determined based on the minimum movement unit of the processing point.
5. The numerical control device according to claim 1, wherein the input energy calculation unit calculates the cumulative energy value per unit length at a certain position.
6. The numerical control device according to claim 5, wherein the input energy calculation unit divides the output energy at a certain position by the speed of the processing point at that position to calculate the cumulative energy value per unit length.
7. A numerical control device according to claim 1, comprising a workpiece shape acquisition unit for acquiring the shape of a workpiece, wherein the threshold acquisition unit changes the threshold according to the shape of the workpiece.
8. A numerical control device according to claim 1, comprising a material acquisition unit for acquiring the material of a workpiece, wherein the threshold acquisition unit changes the threshold according to the material of the workpiece.
9. The numerical control device according to claim 1, wherein the input energy calculation unit excludes energy values from the accumulation target or gradually reduces the accumulated energy values according to the elapsed time after energy input.
10. The numerical control device according to claim 1, further comprising an output unit that outputs the determination result of the determination unit by means of at least one of a signal or a screen display.
11. A computer-readable storage medium on which a program is recorded that causes the computer to operate as: a position acquisition unit that acquires the actual position of the processing point of a non-contact processing machine; an output value acquisition unit that acquires the output energy value of the non-contact processing at the processing point; an input energy calculation unit that calculates the cumulative value of the output energy value input at a certain position; a threshold acquisition unit that acquires a threshold value of the output energy value input at a certain position; and a determination unit that determines whether or not the output energy value input at a certain position exceeds the threshold value at that position.