Measuring device and procedure

Abstract

A measuring device measures a distance from a reference position of a machine tool to a tool detection position of a measuring device for a measurer for measuring a length of a cutting tool, the measuring device including a movement control section that controls movement of a standard member mounted to the machine tool, a detection section that detects a detection signal indicating the tool detection position output in accordance with the measurer being pressed, and a determination section that determines the tool detection position of the measurer based on a position of a leading end of the standard member at a point in time at which the detection signal is detected, wherein the detection section detects the detection signal indicating that the leading end of the standard member is present within a tool detectable range including the tool detection position, the movement control section moves the standard member away from the measurer from a state in which the detection signal is detected by the detection section to a state in which the detection signal is not detected by the detection section, and then moves the standard member toward the measurer to a state in which the detection signal is detected again by the detection section, and the determination section determines the tool detection position based on a position of the standard member at a point in time at which the detection signal is detected again.

Description

Technical Field

[0001] This invention relates to a measuring device and a program. Background Technology

[0002] Conventionally, numerical control devices that control machine tools, etc., execute workpiece machining through machining programs. In order to achieve precision machining of the workpiece, it is desirable to precisely correct the position coordinates of the tool tip to calibrate the mechanical errors of the tool (e.g., a cutting tool) mounted on the machine tool. Therefore, a device for determining the coordinates of the tool tip during actual machining has been proposed (see, for example, Patent Documents 1 and 2).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 11-138392

[0006] Patent Document 2: Japanese Patent Application Publication No. 11-99450 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] When determining the coordinates of the tool tip, a measuring device, for example, is used on the machine tool's worktable. The measuring device is a device capable of detecting the pressing motion of the tool tip from the pressed surface to the tool detection position. The measuring device is configured to send a detection signal to the numerical control unit based on the distance from the pressing motion to the tool detection position. The numerical control unit determines the tool length based on the tool's feed position at the time the detection signal is received.

[0009] Furthermore, since the measuring device is mounted on the machine tool's worktable, it may be exposed to cutting fluid and chips during workpiece machining. Therefore, it is preferable that the measuring device can be verified to operate appropriately when determining the tool detection position.

[0010] Solution for solving the problem

[0011] This disclosure relates to a measuring device that measures the distance from a reference position of the machine tool to a tool detection position of the measuring device for measuring the length of a cutting tool mounted on a machine tool. The measuring device includes: a movement control unit that controls the movement of a standard part having a known length mounted on the machine tool; a detection unit that detects a detection signal indicating the tool detection position output when the measuring device is pressed; and a determination unit that determines the tool detection position of the measuring device based on the position of the tip of the standard part at the time the detection signal is detected. The detection unit detects a detection signal indicating that the tip of the standard part exists within a tool detection range including the tool detection position. The movement control unit moves the standard part away from the measuring device from a state where the detection signal is detected by the detection unit, resulting in a state where the detection unit can no longer detect the detection signal. Then, it moves the standard part towards the measuring device, resulting in a state where the detection unit detects the detection signal again. The determination unit determines the tool detection position based on the position of the standard part at the time the detection signal is detected again.

[0012] Furthermore, this disclosure relates to a program for enabling a computer to function as a measuring device, wherein the measuring device measures the distance from a reference position of the machine tool to a tool detection position of the measuring device for measuring the length of a cutting tool mounted on a machine tool, the program enabling the computer to function as: a movement control unit that controls the movement of a standard part having a known length mounted on the machine tool; a detection unit that detects a detection signal indicating the tool detection position output based on the pressing of the measuring device; and a determination unit that determines the position of the front end of the standard part based on the time point at which the detection signal is detected. To determine the tool detection position of the measuring device, wherein the detection unit detects a detection signal indicating that the tip of the standard part exists within the tool detection range including the tool detection position; after the movement control unit moves the standard part away from the measuring device from a state where the detection unit detects the detection signal, so that the detection unit no longer detects the detection signal, the movement control unit moves the standard part towards the measuring device to change the state where the detection unit detects the detection signal again; and the determining unit determines the tool detection position based on the position of the standard part at the time point when the detection signal is detected again.

[0013] The effects of the invention

[0014] According to this disclosure, a measuring device and procedure can be provided to verify whether the measuring instrument is operating properly. Attached Figure Description

[0015] Figure 1 This is a diagram illustrating the outline of a machine tool in a measuring apparatus according to one embodiment of this disclosure.

[0016] Figure 2 This is a diagram showing the structure of a measuring device according to one embodiment.

[0017] Figure 3A This is a diagram showing the positional relationship between the cutting tool of the machine tool and the measuring device in a measuring apparatus according to one embodiment.

[0018] Figure 3B This is a diagram showing the positional relationship between the cutting tool of the machine tool and the measuring device in a measuring apparatus according to one embodiment.

[0019] Figure 3C This is a diagram showing the positional relationship between the cutting tool of the machine tool and the measuring device in a measuring apparatus according to one embodiment.

[0020] Figure 3D This is a diagram showing the positional relationship between the cutting tool of the machine tool and the measuring device in a measuring apparatus according to one embodiment.

[0021] Figure 4 This is a flowchart illustrating the operation of a measuring device according to one embodiment. Detailed Implementation

[0022] Below, refer to Figures 1 to 4 The measuring device 1 according to one embodiment of the present disclosure will now be described. First, before describing the measuring device 1 according to one embodiment, the machine tool 2 connected to the measuring device 1 will be described.

[0023] like Figure 1 As shown, machine tool 2 is, for example, a device capable of machining workpiece 31 using a cutting tool 21. Specifically, machine tool 2 is a device capable of machining workpiece 31 transported on a worktable 32 using a cutting tool 21. Machine tool 2 machines workpiece 31 by bringing the tip of the cutting tool 21, which is mounted on a tool holder (not shown), into contact with workpiece 31. Furthermore, machine tool 2 is equipped with a measuring device 22.

[0024] The measuring device 22 is used to measure the length (tool length) of the cutting tool 21 mounted on the machine tool 2. For example, the measuring device 22 is used to measure the actual length of the cutting tool 21, which has experienced wear and tear due to machining of the workpiece 31. As an example, the measuring device 22 is used to pre-measure the actual length of the cutting tool 21 before cutting the workpiece 31. The measuring device 22 detects a press made by the cutting tool 21. The measuring device 22 outputs a signal based on the detected press.

[0025] The measuring device 22 is disposed, for example, on the upper surface of the worktable 32 (hereinafter also referred to as reference position F. The upper surface of the worktable 32 is an example of reference position F). The measuring device 22 has a predetermined height. The measuring device 22 has a switch S on its upper part, including the pressed surface U (top surface), which is pressed by the tip of the cutting tool 21. Furthermore, the pressed surface U is generally the vertically upper surface, but depending on the setting direction of the measuring device 22, it may sometimes face a side other than the vertically upper surface. The measuring device 22 outputs a signal indicating that a press has been detected at a predetermined position when the switch S is pressed to a predetermined position. That is, the measuring device 22 outputs a signal indicating that a press has been detected at a predetermined position when the switch S is pressed to a tool detection position P (refer to the tool detection position P) set at a predetermined position after the pressed surface U is pressed. Figure 3D The output indicates that the pressed surface U is pressed down by the cutting tool 21 and the standard part 23.

[0026] Next, the general outline of the measuring device 1 will be described. The measuring device 1 is configured, for example, as part of a numerical control device. The measuring device 1 controls the movement of the cutting tool 21 for the machine tool 2. In addition, the measuring device 1 measures the tool length of the cutting tool 21 by acquiring signals from the measuring device 22.

[0027] In the following embodiment, before measuring the length of the cutting tool 21, the measuring device 1 first determines the tool detection position P set on the measuring device 22. The measuring device 1 uses, for example, a standard part 23 of known length instead of the cutting tool 21 to determine the tool detection position P. Specifically, the measuring device 1 determines the tool detection position P corresponding to the feed rate of the cutting tool 21 preset by the user of the machine tool 2. Furthermore, the measuring device 1 can measure the distance from the reference position F of the machine tool 2 to the tool detection position P of the measuring device 22. Therefore, the measuring device 1 can optimize the tool detection position P based on the feed rate set by the user for the detection of the tool detection position P accompanied by the mechanical movement of the measuring device 22. Thus, accuracy can be improved when measuring the length of the cutting tool 21.

[0028] Furthermore, in the following embodiment, the tool detection position P is determined while verifying whether the measuring device 22 is operating. This protects both the measuring device 22 and the standard part 23.

[0029] Next, refer to Figures 1 to 4 The measuring device 1 and procedure according to one embodiment of this disclosure will now be described. Figure 2 As shown, the measuring device 1 is configured to communicate with the machine tool 2. The measuring device 1 includes a speed acquisition unit 11, a movement control unit 12, a detection unit 13, and a determination unit 14.

[0030] The speed acquisition unit 11 is implemented, for example, by operation of the CPU. The speed acquisition unit 11 acquires a preset feed rate, which is the speed at which the cutting tool 21 moves towards the measuring device 22 when measuring the length of the cutting tool 21. For example, the speed acquisition unit 11 acquires a preset feed rate that moves the cutting tool 21 from above the measuring device 22 towards the measuring device 22 when measuring the tool length. The speed acquisition unit 11 acquires the feed rate of the cutting tool 21, for example, by reading the feed rate from a program storage unit (not shown) that stores the feed rate of the cutting tool 21 when measuring the tool length.

[0031] The movement control unit 12 is implemented, for example, by the CPU. The movement control unit 12 controls, for example, the movement of a standard part 23 of known length mounted on the machine tool 2. The movement control unit 12 moves, for example, the front end of the standard part 23 of known length mounted on the machine tool 2 along the axial direction toward the measuring device 22. The movement control unit 12 moves the standard part 23 at a feed rate obtained by the speed acquisition unit 11, thereby pressing the pressing surface U of the measuring device 22 with the standard part 23. The movement control unit 12 moves, for example, the front end of the standard part 23 of known length mounted on the machine tool 2 along the axial direction (movement direction D) toward the pressing surface U of the measuring device 22. While moving the front end of the standard part 23 mounted on the machine tool 2 to press the pressing surface U of the measuring device 22, the movement control unit 12 also moves the front end of the standard part 23 toward the tool detection position P of the measuring device 22. Furthermore, the movement control unit 12 moves the front end of the standard part 23 to the tool detection position P. In addition, the movement control unit 12 moves the front end of the standard part 23 away from the pressed surface U of the measuring device 22 from the state where the pressed surface U is pressed.

[0032] The detection unit 13 is implemented, for example, by operation of a CPU. The detection unit 13 detects a signal indicating the tool detection position P output when the measuring device 22 is pressed. For example, the detection unit 13 detects an output signal from the measuring device 22 indicating that the tip of the standard piece 23 has reached the tool detection position P, based on further movement of the tip of the standard piece 23 that has contacted the pressed surface U of the switch S. In this embodiment, the detection unit 13 detects a detection signal indicating that the tip of the standard piece 23 exists within the tool detection range R including the tool detection position P. Furthermore, in this embodiment, the measuring device 22 is configured to illuminate a lamp 24 (see reference 24) disposed on the side of its housing when contact with the standard piece 23 is detected. Figure 3A ).

[0033] The determination unit 14 is implemented, for example, by the CPU. The determination unit 14 determines the tool detection position P of the measuring device 22 based on the position of the front end of the standard part 23 at the time the detection signal is detected. In this embodiment, the determination unit 14 determines the position of the pressing surface U of the measuring device 22 after it has been pressed down a predetermined distance as the tool detection position P. For example, at the time the detection signal is detected, the determination unit 14 determines the height (distance) to the tool detection position P based on the position calculated according to the mounting position of the standard part 23 and the known length of the standard part 23.

[0034] Next, refer to Figures 3A-4 The operation flow of the measuring device 1 will be explained. First, the speed acquisition unit 11 acquires a preset feed speed (step S1). Next, the front end of the standard part 23 is positioned to press down the pressing surface U of the measuring instrument 22 (step S2). Specifically, as... Figure 3A As shown, the front end of the standard part 23 is positioned at a location where a detection signal indicating that the front end of the standard part 23 exists within the tool detection range R, including the tool detection position P, will be detected. In this embodiment, the detection unit 13 detects the detection signal generated by the standard part 23 being manually moved into the tool detection range R. Here, the tool detection range R refers to the range within which the contact between the measuring device 22 and the front end of the standard part 23 can be output as a detection signal, and it refers to the position from which a detection signal can be output based on the pressing surface U of the standard part 23, up to a position closer to the measuring device 22 than that position (for example, typically below), where the switch S can be pressed and the contact can be output as a detection signal.

[0035] Next, the movement control unit 12 moves the standard part 23 away from the measuring device 22 (typically, raises it) from the state where the detection signal is detected by the detection unit 13 (step S3). Then, the detection unit 13 detects the point in time during the process of the standard part 23 moving away from the measuring device 22, when the detection unit 13 no longer detects the detection signal (step S4). For example, the detection unit 13 detects the point in time from the state where the switch S detects the contact of the standard part 23 to the point where it can no longer detect the contact of the standard part 23, for example, the point in time when the front end detection of the standard part 23 changes from the state where the switch S detects the contact of the standard part 23. Figure 3B As shown, the determining unit 14 determines the position of the front end of the standard part 23 at the time of switching as the first detection limit position L (typically, the upper limit position).

[0036] Next, as Figure 3CAs shown, the movement control unit 12 continues to move the standard part 23 away from the measuring device 22, until the detection unit 13 can no longer detect the detection signal. The movement control unit 12 moves the standard part 23 to an arbitrarily determined position (step S5). Next, the movement control unit 12 moves the standard part 23 toward the measuring device 22 (typically, lowers it). Specifically, as... Figure 3D As shown, the movement control unit 12 moves the front end of the standard part 23 toward the measuring device 22 at a feed speed obtained by the speed acquisition unit 11 (step S6).

[0037] Next, it is determined whether the detection unit 13 has detected the detection signal again (step S7). If the detection signal is detected (step S7: "Yes"), the process proceeds to step S8. On the other hand, if the detection signal is not detected (step S7: "No"), the process proceeds to step S9.

[0038] In step S8, the determining unit 14 determines the tool detection position P based on the position of the standard part 23 at the time when the detection signal is detected again. Specifically, the determining unit 14 determines the tool detection position P based on the position of the front end of the standard part 23 at the time when the detection signal is detected again. Thus, the processing according to this procedure ends.

[0039] In step S9 (step S7: "No"), the movement control unit 12 moves the standard component 23 any distance from the coordinate value of the time point detected in step S4 towards the measuring device 22 (in the -Z direction). If the detection signal is still not detected even after this, the movement control unit 12 raises the standard component 23 to the position of step S5 and then stops the standard component 23, and then outputs a stop alarm (step S10). Thus, the processing according to this procedure ends.

[0040] Next, the procedure of this disclosure will be described. Each structure included in the measuring device 1 can be implemented by hardware, software, or a combination thereof. Here, implementation by software means implementation by a computer reading and executing the program.

[0041] Programs can be stored and supplied to a computer using a wide variety of types of non-transitory computer-readable media. Non-transitory computer-readable media include a wide variety of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (e.g., floppy disks, magnetic tapes, hard disk drives), magneto-optical recording media (e.g., magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (e.g., mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (Random Access Memory)). Alternatively, programs can also be supplied to a computer via a wide variety of transient computer-readable media. Examples of transient computer-readable media include electrical signals, optical signals, and electromagnetic waves. Transient computer-readable media can supply programs to a computer via wired communication paths such as wires and optical fibers, or via wireless communication paths.

[0042] The measuring device 1 and the procedure according to one embodiment achieve the following effects.

[0043] (1) The measuring device 1 measures the distance from the reference position of the machine tool 2 to the tool detection position P of the measuring device 22 for measuring the length of the cutting tool 21 mounted on the machine tool 2. The measuring device 1 includes: a movement control unit 12 that controls the movement of a standard part 23 with a known length mounted on the machine tool 2; a detection unit 13 that detects a detection signal indicating the tool detection position P output when the measuring device 22 is pressed; and a determination unit 14 that determines the tool detection position P of the measuring device 22 based on the position of the front end of the standard part 23 at the time when the detection signal is detected. The detection unit 13 detects a detection signal indicating that the front end of the standard part 23 exists within the tool detection range R, which includes the tool detection position P. After the movement control unit 12 moves the standard part 23 away from the measuring device 22 from the state where the detection unit 13 detects the detection signal, so that the detection unit 13 can no longer detect the detection signal, the movement control unit 12 moves the standard part 23 toward the measuring device 22 so that the detection unit 13 detects the detection signal again. The determination unit 14 determines the tool detection position P based on the position of the standard part 23 at the time point when the detection signal is detected again.

[0044] Therefore, the tool detection position P can be determined while switching from a state where a detection signal is detected to a state where a detection signal is not detected. Thus, it is possible to verify whether the measuring device 22 operates appropriately during measurement.

[0045] (2) During the process of the detection unit 13 detecting the standard part 23 moving away from the measuring device 22, at the point in time when the detection unit 13 switches to a state where the detection unit 13 cannot detect a detection signal, the determination unit 14 determines the position of the front end of the standard part 23 at the switching point as the first detection limit position L. When the movement control unit 12 moves the standard part 23 toward the measuring device 22, it restricts the movement of the front end of the standard part 23 beyond the first detection limit position L by a first predetermined distance. Therefore, in the case where the detection signal cannot be detected due to poor contact of the measuring device 22, the movement of the front end of the standard part 23 can be restricted to a distance greater than the first predetermined distance. Thus, the measuring device 22 and the standard part 23 can be protected.

[0046] (3) The measuring device 1 also includes a speed acquisition unit 11 for acquiring a preset feed rate, which is the speed at which the cutting tool 21 moves toward the measuring device 22 when measuring the length of the cutting tool 21. The movement control unit 12 moves the standard part 23 toward the measuring device 22 at the feed rate acquired by the speed acquisition unit 11. Thus, the tool detection position P can be determined using the feed rate used to measure the tool length of the cutting tool 21. Therefore, for the contact measuring device 22, the deviation of the time point of the output detection signal caused by the different feed rates can be taken into account, thereby improving the accuracy of the tool length measurement of the cutting tool 21.

[0047] The preferred embodiments of the measuring device and program of this disclosure have been described above. However, this disclosure is not limited to the above embodiments and appropriate modifications can be made.

[0048] For example, in the above embodiment, the measuring device 1 can be configured as part of a calibration device for calibrating the coordinates of the tool detection position P of the measuring device 22. This improves the accuracy of tool length measurement when actually measuring the tool length of the cutting tool 21.

[0049] Alternatively, in the above embodiment, when the standard part 23 is moved away from the measuring device 22, if the movement beyond the second predetermined distance does not switch to a state where the detection signal cannot be detected, the determination unit 14 may stop determining the tool detection position P. For example, even if the front end of the standard part 23 moves beyond the second predetermined distance of the first detection limit position L and the detection signal does not become disconnected, the determination unit 14 may stop determining the tool detection position P. Here, the second predetermined distance is preferably a length longer than the length of the tool detection range R. As a result, malfunctions of the measuring device 22, such as the switch S of the measuring device 22 sticking and thus not moving mechanically, can be detected.

[0050] Explanation of reference numerals in the attached figures

[0051] 1: Measuring device; 2: Machine tool; 11: Speed ​​acquisition unit; 12: Movement control unit; 13: Detection unit; 14: Determination unit; 21: Cutting tool; 23: Standard part; 22: Measuring device; 32: Worktable; F: Reference position; L: First detection limit position; P: Tool detection position; Q: Specified position; R: Tool detection range; S: Switch; U: Pressed surface.

Claims

1. A measuring device that measures the distance from a reference position of the machine tool to a tool detection position of the measuring device for measuring the length of a cutting tool mounted on a machine tool, the measuring device comprising: A movement control unit that controls the movement of a standard component of known length mounted on the machine tool; The detection unit detects a detection signal indicating the detection position of the tool, output when the measuring device is pressed; and The determining unit determines the tool detection position of the measuring device based on the position of the front end of the standard part at the time point when the detection signal is detected. in, The detection unit detects a signal indicating that the front end of the standard part exists within the tool's detectable range, including the tool detection position. After the movement control unit moves the standard piece away from the measuring device from a state where the detection unit detects a detection signal, thus changing the state where the detection unit can no longer detect a detection signal, it moves the standard piece towards the measuring device to change the state where the detection unit detects a detection signal again. The determining unit determines the tool detection position based on the position of the standard part at the time point when the detection signal is detected again. Furthermore, the detection unit switches to a state where it cannot detect a detection signal during the process of the standard piece moving away from the measuring instrument. The determining unit defines the position of the front end of the standard part at the point in time when the detection unit cannot detect a detection signal during the process of the standard part moving away from the measuring device as the first detection limit position. When the movement control unit moves the standard component toward the measuring device, it restricts the movement of the front end of the standard component beyond a first predetermined distance from the first detection limit position.

2. The measuring device according to claim 1, wherein, It also includes a speed acquisition unit for acquiring a preset feed rate, which is the speed at which the cutting tool moves toward the measuring device when measuring the length of the cutting tool. The movement control unit causes the standard part to move toward the measuring device at a feed rate obtained by the speed acquisition unit.

3. The measuring device according to claim 1 or 2, wherein, The detection unit detects the detection signal generated by the standard piece being manually moved into the detection range of the tool.

4. The measuring device according to claim 1 or 2, wherein, When the standard part is moved away from the measuring device, if the state of no detection signal is switched to when the movement exceeds the second predetermined distance, the determination unit stops determining the detection position of the tool.

5. The measuring device according to claim 3, wherein, When the standard part is moved away from the measuring device, if the state of no detection signal is switched to when the movement exceeds the second predetermined distance, the determination unit stops determining the detection position of the tool.

6. A non-transitory computer-readable medium storing a program for enabling a computer to function as a measuring device, wherein, The measuring device measures the distance from a reference position of the machine tool to a tool detection position of the measuring device for measuring the length of a cutting tool mounted on a machine tool. The program enables the computer to function as the following components: A movement control unit that controls the movement of a standard component of known length mounted on the machine tool; The detection unit detects a detection signal indicating the detection position of the cutting tool, which is output when the measuring device is pressed. as well as The determining unit determines the tool detection position of the measuring device based on the position of the front end of the standard part at the time point when the detection signal is detected. The detection unit detects a signal indicating that the front end of the standard part exists within the tool's detectable range, including the tool detection position. After the movement control unit moves the standard piece away from the measuring device from a state where the detection unit detects a detection signal, thus changing the state where the detection unit can no longer detect a detection signal, it moves the standard piece towards the measuring device to change the state where the detection unit detects a detection signal again. The determining unit determines the tool detection position based on the position of the standard part at the time point when the detection signal is detected again. Furthermore, the detection unit switches to a state where it cannot detect a detection signal during the process of the standard piece moving away from the measuring instrument. The determining unit determines the position of the front end of the standard part at the switching time point as the first detection limit position. When the movement control unit moves the standard component toward the measuring device, it restricts the movement of the front end of the standard component beyond a first predetermined distance from the first detection limit position.

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