JP2007090514A - Abnormality determination method and abnormality determination device in mounting tool holder to spindle device in machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an abnormality determination device in mounting a tool holder to a spindle device in a machine tool, which surely cleans the inner peripheral surface of a taper hole of a spindle and the outer peripheral surface of a taper shank part of the tool holder, and confirms the presence/absence of the tool holder. <P>SOLUTION: The spindle device is provided with a cleaning air supply mechanism for supplying cleaning air to a gap G1 formed between the inner peripheral surface of the taper hole 28a of the spindle 28 and the outer peripheral surface of the taper shank part 34 of the tool holder 5. A pressure sensor 50 is provided in an air supply passage of the air supply mechanism, whereby after the supply operation of the cleaning air, the air pressure is measured by the pressure sensor 50 to determine the presence/absence of the tool holder 5 according to the magnitude of measured air pressure. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an abnormality determination method and an abnormality determination apparatus when a tool holder is mounted on a spindle device in a machine tool.

  Generally, in a spindle device of a machine tool, a spindle is rotatably supported on an inner peripheral surface of a spindle head, and a taper shank portion of a tool holder is detachably mounted in a tapered hole formed in a tip portion of the spindle. A clamp mechanism for clamping the tool holder is provided at the tip of the tool. Further, the machine tool is provided with a tool changer for automatically detaching and replacing the tool holder with respect to the spindle device. Further, the spindle device is provided with an air supply mechanism for supplying cleaning air for cleaning the contact surface between the tapered shank portion and the tapered hole of the tool holder.

In the cleaning operation by the air supply mechanism, the tool holder is held by the holding portion of the tool changer, and a slight gap is formed between the outer peripheral surface of the tapered shank portion of the tool holder and the inner peripheral surface of the tapered hole. Form. Then, air is injected into the gap from an air injection hole opened on the inner peripheral surface of the tapered hole of the main shaft, and the outer peripheral surface of the tool holder and the inner peripheral surface of the tapered hole are cleaned. (See Patent Document 1)
On the other hand, what was disclosed by patent document 2 is proposed as a tool holder mounting | wearing confirmation apparatus of the spindle apparatus in a machine tool. This mounting confirmation device supplies constant pressure air from the constant pressure air supply device to the contact interface between the taper hole of the spindle and the taper surface of the tool holder through the conduit, throttle and nozzle, and the pressure in the conduit at that time is a pressure switch. And whether or not the tool holder is mounted can be confirmed based on the detected pressure level.
JP 7-214454 A Japanese Utility Model Publication No. 49-14585

  However, the cleaning method of the spindle hole of the spindle of the spindle device and the taper shank portion of the tool holder in the machine tool disclosed in Patent Document 1 does not have a device for checking the mounting state of the tool holder. There was a problem that could not be confirmed.

  On the other hand, although the tool holder mounting confirmation device of the spindle device disclosed in Patent Document 2 can confirm the mounting of the tool holder, the pressure of the air supplied from the constant pressure air supply device decreases because of the restriction. There is a problem that the air pressure necessary for cleaning cannot be ensured, and the taper hole of the spindle and the taper surface of the tool holder cannot be cleaned.

  The present invention solves the above-described problems in the prior art, can clean the contact surface between the tapered hole of the spindle and the tapered shank portion of the tool holder, and can determine the presence or absence of the tool holder. An object of the present invention is to provide an abnormality determination method and an abnormality determination device when a tool holder is mounted on a spindle device in a machine tool.

  In addition to the above object, another object of the present invention is to provide an abnormality determination method and an abnormality determination device at the time of mounting a tool holder on a spindle device in a machine tool that can accurately determine the presence or absence of a tool holder. It is in.

  In order to solve the above problems, the invention according to claim 1 is characterized in that the taper shank portion of the tool holder is removably mounted in the taper hole at the tip of the main shaft rotatably supported by the main shaft head of the main shaft device. A machine tool provided with an air injection hole for supplying cleaning air for the taper shank portion in the tapered hole with respect to the main shaft, and an air supply passage for supplying cleaning air to the air injection hole from a pressure air supply source , The pressure or flow rate of the air supplied from the pressure air supply source to the air supply passage is measured, and the determination reference value set according to the measured value and stored in the storage medium is newly measured. The gist is to determine the presence or absence of the tool holder based on the measured value of pressure or flow rate.

  According to a second aspect of the present invention, in the first aspect, in a state in which the taper shank portion of the tool holder has a predetermined gap with respect to the tapered hole, the air injection is started from the air injection hole. The first measurement value of the pressure or flow rate is measured at the time, a determination reference value with a positive constant added to the first measurement value is set, and at a predetermined time after the determination reference value is set, In a state where the tapered shank portion is clamped in the tapered hole, a second measured value of pressure or flow rate is measured, and the presence or absence of the tool holder is determined by comparing the second measured value with the determination reference value. This is the gist.

  A third aspect of the present invention is the method according to the first or second aspect, wherein the pressure or flow rate of air supplied to the air injection hole is measured in a state where the air injection hole is opened, and is set according to the measured value. The clogging of the air injection hole is based on the determination reference value for determining clogging stored in the storage medium and the measured value of the pressure or the flow rate newly measured with the air injection hole opened. The gist is to determine the presence or absence.

  According to a fourth aspect of the present invention, in the state where the tapered shank portion of the tool holder is clamped in the tapered hole in any one of the first to third aspects, the air pressure or flow rate of the air injection hole is set. Measured, newly set in accordance with the determination reference value for defective mounting determination set according to the measured value and stored in the storage medium, and the taper shank portion of the tool holder clamped in the tapered hole. The gist of the present invention is to determine whether or not there is a mounting failure of the tapered shank portion with respect to the tapered hole based on the measured value of the pressure or flow rate.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the source pressure of the pressure air supply source is measured in a state where the supply of air to the air injection hole is shut off, and the source The gist is to determine whether or not there is an abnormality in the original pressure based on the measured value of the pressure and the lowest determination reference value and the highest determination reference value for the original pressure stored in the storage medium in advance.

  According to a sixth aspect of the present invention, a taper shank portion of a tool holder is removably attached to a tapered hole at a tip portion of a main shaft rotatably supported by a main shaft head of the main shaft device, and the tapered hole is formed in the tapered hole with respect to the main shaft. In a machine tool provided with an air injection hole for supplying cleaning air for the taper shank portion, and provided with an air supply passage for supplying cleaning air from a pressure air supply source to the air injection hole, air is supplied to the air supply passage. Pressure measuring means or flow rate measuring means for measuring pressure or flow rate is provided, pressure measurement value or flow rate measurement value from the pressure measuring means or flow rate measuring means, set according to the measured value, and stored in a storage medium The gist is that a tool holder presence / absence determining unit that determines the presence / absence of the tool holder is provided based on a determination reference value and a newly measured pressure or flow rate measurement value.

  According to a seventh aspect of the present invention, in the sixth aspect, in the state where the determination unit has a predetermined gap between the tapered shank portion of the tool holder with respect to the tapered hole, the air is injected from the air injection hole. A determination criterion for setting a determination criterion value in which a positive constant of pressure or flow rate is added to the first measured value of measured pressure or flow rate at a predetermined time set by the first timing setting unit after starting. After the setting of the value setting unit and the determination reference value, at a predetermined time set by the second timing setting unit, the pressure or flow rate newly measured with the tapered shank portion clamped in the tapered hole The second measurement value is compared with the determination reference value to determine whether the tool holder is present or not, and a tool holder presence / absence determining unit is used.

  According to an eighth aspect of the present invention, in the seventh aspect, the first timing setting unit uses a time when the tool holder is unclamped from the spindle as a first timing setting reference, and a predetermined time has elapsed from the setting reference. Then, the gist is that the time when the pressure measurement value or the flow rate measurement value measured by the pressure measurement unit or the flow rate measurement unit is substantially smoothed and constant is set as the first timing.

  A ninth aspect of the present invention is the method according to the seventh aspect, wherein the second timing setting unit is configured such that a time when the tool holder is clamped to the spindle is set as a second timing setting reference, and a predetermined time has elapsed from the setting reference. The gist is that the time is set as the second timing.

  A tenth aspect of the present invention is the measurement value of the original pressure of the pressure air supply source measured in a state where the supply of air to the air injection hole is shut off in any one of the sixth to ninth aspects. The gist of the present invention is that it includes a source pressure abnormality determination unit that determines whether or not the source pressure is abnormal based on a minimum determination reference value and a maximum determination reference value for the source pressure stored in advance in a storage medium.

  The invention described in claim 11 is the abnormality determination reference value setting unit for determining the clogging abnormality of the air injection hole according to any one of claims 6 to 10, and the air injection hole being opened, A measurement value of the pressure or flow rate of air supplied to the air injection hole, a determination reference value set according to the measurement value and stored in the storage medium, and a state in which the air injection hole is opened Thus, the present invention includes an abnormality determination unit that determines whether or not the air injection hole is clogged based on a newly measured pressure or flow rate measurement value.

  The invention according to claim 12 is the determination reference value setting unit for setting a reference value of pressure or flow rate for determining poor mounting of the tool holder to the tapered hole in any one of claims 6 to 11, In a state where the taper shank portion of the tool holder is clamped in the taper hole, the measured value of the pressure or flow rate of the air supplied to the air injection hole, and the setting set according to the measured value and stored in the storage medium Based on the determination reference value for defect determination and the taper shank portion of the tool holder clamped in the tapered hole, the taper shank portion with respect to the tapered hole is newly measured based on the measured value of the pressure or flow rate. The gist of the present invention is that it includes a tool mounting failure determination unit that determines the presence or absence of mounting failure.

(Function)
According to the first aspect of the present invention, the cleaning air is introduced into the gap between the inner peripheral surface of the tapered hole of the spindle and the outer peripheral surface of the tapered shank portion of the tool holder through the air supply passage and the air injection hole from the pressure air supply source. Can be used to clean the inner peripheral surface of the tapered hole and the outer peripheral surface of the tapered shank. Further, the pressure or flow rate of the air supplied from the pressure air supply source to the air supply passage is measured, and the determination reference value set according to the measured value and stored in the storage medium is newly measured. The presence or absence of the tool holder can be determined based on the measured value of pressure or flow rate.

  In the invention according to claim 2, a determination reference value is set in which a positive constant of pressure or flow rate is added to the first measurement value of measured pressure or flow rate. Further, the measured second measured value is compared with the determination reference value to determine the presence or absence of the tool holder. Accordingly, even if the pressure of the air supplied from the pressure air supply source fluctuates, the determination reference value is set based on the first measured value of the fluctuating air pressure, so the presence / absence of the tool holder is determined. It can be performed with high accuracy.

  The invention according to claim 3 measures the pressure or flow rate of the air supplied to the air injection hole in a state where the air injection hole is opened, and is set according to the measured value and the measured value. Whether or not the air injection hole is clogged can be determined based on the determination reference value for determining clogging stored in the storage medium and the newly measured pressure or flow rate.

  In the invention according to claim 4, in the state where the tapered shank portion of the tool holder is clamped in the tapered hole, the air pressure or flow rate of the air injection hole is measured, and is set according to the measured value. Whether or not there is a mounting failure of the tapered shank portion with respect to the tapered hole can be determined based on the determination reference value for determining the mounting failure stored in the storage medium and the newly measured pressure or flow rate.

  According to a fifth aspect of the present invention, the source pressure of the pressure air supply source is measured in a state where the supply of air to the air injection hole is shut off, and the measured value of the source pressure is stored in advance in a storage medium. The presence or absence of abnormality of the original pressure can be determined based on the minimum determination reference value and the maximum determination reference value for the original pressure.

  In the seventh aspect of the invention, the determination reference value is set by adding a positive constant of the pressure or flow rate to the first measurement value of the measured pressure or flow rate. Further, the measured second measured value is compared with the determination reference value to determine the presence or absence of the tool holder. Accordingly, even if the pressure of the air supplied from the pressure air supply source fluctuates, the determination reference value is set based on the first measured value of the fluctuating air pressure, so the presence / absence of the tool holder is determined. It can be performed with high accuracy.

  In the invention according to claim 8, the first timing setting unit uses the time when the tool holder is unclamped as a setting reference for the first timing. For this reason, it is not necessary to provide a dedicated setting reference, and it is possible to easily create software for determining the presence or absence of the tool holder of the control device.

  In a ninth aspect of the present invention, the second timing setting section uses a time when the tool holder is clamped on the spindle as a setting reference. For this reason, it is not necessary to provide a dedicated setting reference, and it is possible to easily create software for determining the presence or absence of the tool holder of the control device.

  The present invention can clean the contact surface between the tapered hole of the spindle and the tapered shank portion of the tool holder, and can determine the presence or absence of the tool holder.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.
As shown in FIG. 10, a saddle 2 is disposed on the bed 1 so as to be movable in the Z-axis direction (left-right direction in FIG. 10). A column 3 is supported on the saddle 2 so as to be movable in the X-axis direction (a direction orthogonal to the plane of FIG. 10). A tool 6 such as a drill is detachably attached to the spindle device 4 via a tool holder 5. Then, in a state where the spindle device 4 is moved and arranged at the lower machining position P1 indicated by the solid line in FIGS. 10 and 11, the saddle 2 is moved toward and away from the workpiece on the table (not shown) together with the tool holder 5. The workpiece 6 is subjected to predetermined processing by the tool 6.

  A tool changer 8 is attached to the tip of the frame 7 standing on the bed 1. The frame 7 is mounted with a turning motor 9 that can rotate forward and backward, and a tool magazine 11 is mounted on the rotating shaft 10 thereof. The tool magazine 11 is formed in a notch disk shape as shown in FIG. 11 when viewed from the axial direction, and gripping portions 12 for gripping the tool holder 5 are mounted at a plurality of locations on the outer periphery thereof. Then, the spindle device 4 is lifted from the tool change preparation position P3 in a state where the empty gripping portion 12 ′ of the tool magazine 11 is moved to the tool change position P2 indicated by the chain line of the arrow in FIG. The tool holder 5 mounted on the spindle device 4 is transferred to the empty gripping portion 12 '. When the tool holder 5 gripped by the gripping portion 12 is mounted on the spindle device 4, the tool magazine 11 is opened with the spindle device 4 retracted in the Z-axis direction at the tool change position P2 in FIG. After the gripping part 12 that has turned and gripped the new tool is moved to the tool change position P2, the spindle device 4 is moved forward.

Next, the configuration of the spindle device 4 will be described.
As shown in FIG. 3, the spindle head 21 of the spindle device 4 is composed of an outer cylinder 22A and an inner cylinder 22B, and a main shaft 23 is rotatably supported via a plurality of bearings 24 inside the inner cylinder 22B. Yes. A drawing bar 25 is disposed in a through hole 23 a formed along the axis of the main shaft 23. The drawing bar 25 is inserted in the through hole 23a of the main shaft 23 so as to be slidable in the front-rear direction (left-right direction in FIG. 3). The drawing bar 25 is urged in the backward direction (right side in FIG. 3), that is, in the clamping position, by a disc spring 26 as an urging member accommodated in the through hole 23a.

  An outer flange 27 is fixed to the front end face of the spindle head 21 by a bolt (not shown), and an inner flange 28 is fixed to the front end face of the spindle 23 by a bolt (not shown). As shown in FIG. 3, a collar 29 having a horizontal cylindrical shape is connected to the front end portion of the main shaft 23 inside the inner flange 28, and a pair of radial ends of the front end portion of the collar 29 are opposed to each other in a pair. A holding hole 30 is provided therethrough. A ball 31 is inserted into each holding hole 30.

  At the front end of the drawing bar 25, as shown in FIG. 1, a pair of first recesses 32 are drilled in a hemispherical shape at positions corresponding to the holding holes 30 of the collar 29, and A second recess 33 is formed in a tapered shape in front of each first recess 32. The first recess 32 and the second recess 33 can be engaged with the pair of balls 31. The inner peripheral surface of the inner flange 28 is a tapered hole 28a formed in a tapered shape that expands toward the front end side (left side in FIG. 1).

  As shown in FIG. 3, a tool holder 5 on which a tool 6 is mounted is detachably mounted on the front end portion of the main shaft 23. As shown in FIG. 1, a grip groove 5 b that is gripped by the grip portion 12 is formed on the outer peripheral surface of the flange portion 5 a of the tool holder 5. A tapered shank portion 34 is integrally formed rearward on the rear end surface 5c of the flange portion 5a of the tool holder 5. A pair of fixing holes 35 penetrates the central portion of the tapered shank portion 34 at a position corresponding to the holding hole 30 of the collar 29, and can engage with the pair of balls 31.

  Therefore, when the drawing bar 25 is moved forward as shown in FIG. 1 against the urging force of the disc spring 26 (see FIG. 3), the ball 31 in the holding hole 30 formed in the collar 29 is the first. 1 It falls into the recessed part 32, the ball | bowl 31 remove | deviates from the fixing hole 35 of the taper shank part 34, and the tool holder 5 will be in an unclamped state. On the contrary, in the state where the drawing bar 25 is moved backward as shown in FIG. 3 by the biasing force of the disc spring 26, the ball 31 in the holding hole 30 is separated from the first recess 32 by the second recess 33, and is fixed to the fixing hole. The tool holder 5 is in a clamped state as shown in FIG.

  In the first embodiment, the tool holder 5 includes the drawing bar 25, the disc spring 26, the collar 29, the holding hole 30, the ball 31, the first concave portion 32, the second concave portion 33, the tapered shank portion 34, the fixing hole 35, and the like. The clamping mechanism K is configured. Although not shown, at the rear end portion of the spindle device 4, the drawing bar 25 is switched from the clamping position shown in FIGS. 2 and 3 to the unclamping position shown in FIG. 1 against the urging force of the disc spring 26. A clamp release mechanism is provided.

Next, the configuration of the main part of the present invention will be described.
As shown in FIG. 3, the main spindle head 21 and the outer flange 27 are configured to guide the pressure air sent from the pressure air supply source 40 through the air supply pipe 41 to the inner flange 28 attached to the tip of the main spindle 23. Air supply passages 42 and 43 are formed. As shown in FIG. 1, an annular groove 27 b communicating with the air supply passage 43 is formed on the inner peripheral surface 27 a of the outer flange 27. An air supply passage 44 is formed in the inner flange 28 so as to communicate with the annular groove 27b. A plurality of air passages 45 are formed in the inner flange 28 so as to be directed in the front-rear direction, and each air passage 45 communicates with the air supply passage 44. The first to third air injection holes 46, 47 and 48 communicate with each air passage 45. The first air injection hole 46 is cleaned by blowing pressure air onto the rear end surface 5c of the tool holder 5 main body. The second and third air injection holes 47 and 48 are cleaned by blowing air onto the outer peripheral surface 34a of the tapered shank portion 34, respectively. As shown in FIG. 4, the air injection holes 46 are provided at, for example, eight locations, and the air injection holes 47 and 48 are provided at four locations, respectively.

  As shown in FIG. 3, the air supply pipe 41 is provided with an electromagnetic on-off valve 49 having an open port 49a and a closed port 49b. The air supply pipe 41 is provided with a pressure sensor 50 for detecting the pressure air pressure so as to be located downstream of the on-off valve 49.

Next, a control system for controlling various operations of the machine tool will be described with reference to FIG.
The control device 51 is provided with a central processing unit (CPU) 52 for performing various kinds of arithmetic processing. The central processing unit 52 has a read only memory (ROM) in which a program for performing a control operation of the machine tool is recorded. 53) and a random access memory (RAM) 54 as a storage medium for storing various data. A pressure measurement value from the pressure sensor 50 is input to the central processing unit 52 via an analog / digital converter and interface 55 (not shown). A drive circuit 57 is connected to the central processing unit 52 via an interface 56, and an X-axis moving mechanism for moving the spindle device 4 in the X, Y, and Z-axis directions is connected to the drive circuit 57. 58, a Y-axis moving mechanism 59 and a Z-axis moving mechanism 60 are connected, and a turning motor 9 for the tool magazine, a pressure air supply source 40, and an on-off valve 49 are connected. An input device 61 such as a keyboard is connected to the central processing unit 52 via an interface 62. A display device 64 having a display is connected to the central processing unit 52 through an interface 63.

  The central processing unit 52 is provided with an operation control unit 71 for executing various operations such as a workpiece machining operation of the machine tool and an exchange operation of the tool holder 5 based on an operation program stored in the ROM 53. . The central processing unit 52 is provided with a first timing setting unit 72. The air pressure measured by the pressure sensor 50 is set as the first measured value PS1 in synchronization with a predetermined time preset by the first timing setting unit 72, for example, the turning timing of the tool magazine 11. Yes. The central processing unit 52 has a determination reference value setting unit 73 for setting a determination reference value PK by adding a positive constant Pc (for example, 0.02 MPa) to the set first measurement value PS1. Is provided. Further, after the determination reference value PK is set, the central processing unit 52 sets the newly measured measurement pressure as the second measurement value PS2 at a predetermined time set by the second timing setting unit 74. I am doing so. The central processing unit 52 is provided with a determination unit 75 that compares the set second measurement value PS2 with the determination reference value PK to determine the presence or absence of a tool holder.

  In the first embodiment, the tool holder 5 includes the pressure sensor 50, the control device 51, the central processing unit 52, the first timing setting unit 72, the determination reference value setting unit 73, the second timing setting unit 74, the determination unit 75, and the like. The determination means which determines the presence or absence of is comprised.

  The operation of the machine tool of the first embodiment will be described. The following operations are performed as follows based on various control signals from the operation control unit 71 stored in the CPU 52 of the control device 51 shown in FIG.

  When machining the workpiece of this machine tool, as shown in FIGS. 2 and 3, the X, Y, and Z triaxial moving mechanisms 58 to 60 are mounted with a predetermined tool 6 such as a drill attached to the tip of the main shaft 23. By this operation, the spindle device 4 is moved to the lower machining position P1 indicated by the solid line in FIG. In this state, while the tool holder 5 is rotated by the main shaft 23, the saddle 2 is moved toward or away from a workpiece on a table (not shown), and the workpiece 6 is subjected to predetermined processing such as drilling. .

  After this processing is completed, an operation is performed in which the old tool 6 mounted on the spindle device 4 is replaced with the new tool 6 held by the grip portion 12 of the tool magazine 11. This replacement operation will be described with reference to the flowcharts shown in FIGS. 6 and 7 and FIGS.

  When the tool holder 5 is exchanged in the clamped state where the tool holder 5 is mounted on the main shaft 23 as shown in FIG. 2 and FIG. 3, as shown in step S1 of FIG. As a result, the X, Y and Z triaxial moving mechanisms 58 to 60 are operated, and the spindle 23 holding the tool holder 5 of the old tool 6 is moved to the tool change preparation position P3 immediately below the tool change position P2 shown in FIG. The In step S2, the turning motor 9 is operated, and the empty gripping portion 12 'of the tool magazine 11 is turned to the tool changing position P2. In step S3, the main shaft 23 is raised by the Y-axis moving mechanism 59, the tool holder 5 is moved to the empty gripping portion 12 ', and the tool holder 5 is switched to the unclamped state by operation of a clamp release mechanism (not shown). In this state, as shown in FIG. 1, there is a gap G1 between the outer peripheral surface 34a of the tapered shank portion 34 and the tapered hole 28a of the inner flange 28, the rear end surface 5c of the flange portion 5a, and the front end of the inner flange 28. A gap G2 is formed between the surface 28b.

  In step S4, the on-off valve 49 is switched from the closed port 49b to the open port 49a, and the first to third air is supplied from the pressure air supply source 40 through the air supply pipe 41, the air supply passages 42, 43, 44, and the air passage 45. Air is supplied to the injection holes 46 to 48, cleaning air is injected into the gaps G1 and G2, and the tapered hole 28a and the tapered shank portion 34 are cleaned.

  FIG. 8 shows a pressure curve LP of air detected by the pressure sensor 50 when the tool holder 5 is present, and FIG. 9 shows a pressure curve LP when the tool holder 5 is not present. At time h1 and time h2 in FIG. 8, as described in step S2 in FIG. 6, the empty gripping portion 12 ′ of the tool magazine 11 is moved from the retracted position to the tool changing position P2. At time h3 when a predetermined time has elapsed from time h2, the tool holder 5 is in an unclamped state as described in step S3 of FIG. 6, and at the same time, the on-off valve 49 is opened and cleaned as described in step S4. Supply of operating air is started.

  In step S5, simultaneously with the start of air supply, pressure measurement of the supply air by the pressure sensor 50 is started, and the measured pressure Pe rapidly increases as shown in FIG. As shown in step S6, the main shaft 23 is retracted by the Z-axis moving mechanism 60 at time h4 shown in FIG. 8, and the tool holder 5 is transferred to the empty gripping portion 12 ′. As a result, the gaps G1 and G2 are eliminated, so that the measured pressure Pe decreases from the time h4 to a substantially constant pressure, as shown by the pressure curve LP.

  Next, in step S7, the tool magazine 11 is turned between the time h5 and the time h6 when a predetermined time has elapsed from the time h4 shown in FIG. 8, and the tool holder 5 holding the new tool 6 is moved to the tool change position P2. Moved. In step S8, the pressure measured at time h6 as the first timing set by the first timing setting unit 72 is set as the first measured value PS1. That is, in the first embodiment, the time h3 at which the tool holder 5 is in an unclamped state by the first timing setting unit 72 is a setting reference for the first timing, and the time at which a predetermined time has elapsed from the time h3. h6 is the first timing. The first measured value PS1 is stored in the RAM 54. In step S <b> 9, the main shaft 23 is advanced by the Z-axis moving mechanism 60, and the taper shank portion 34 of the tool holder 5 of the new tool 6 held by the tool magazine 11 is inserted into the tapered hole 28 a of the main shaft 23.

  Next, in step S10 shown in FIG. 7, the determination reference value setting unit 73 adds a positive constant (increase amount) Pc (for example, 0.02 MPa) of pressure to the set first measurement value PS1 for determination. A reference value PK (= PS1 + Pc) is set. The determination reference value PK is stored in the RAM 54. As shown in step S11, at time h7, the tool holder 5 of the new tool 6 is clamped by the clamping mechanism K of the spindle device 4. In step S12, the pressure measured at time h8 as the second timing set by the second timing setting unit 74 is stored in the RAM 54 as the second measured value PS2. That is, in the first embodiment, the time h7 when the clamping operation of the tool holder 5 by the spindle device 4 is performed by the second timing setting unit 74 becomes the second timing setting reference, and a predetermined time has elapsed from this time h7. The time h8 is the second timing. In step S13, the determination unit 75 determines whether or not the second measurement value PS2 exceeds the determination reference value PK (= PS1 + Pc). If it is determined as YES in step S13, it is determined in step S14 that the tool holder 5 is present, and the determination result is displayed on the display device 64. In step S15, the spindle 23 is moved by the Y-axis moving mechanism 59. Is moved downward, the tool holder 5 is removed from the tool magazine 11, and the tool holder 5 of the new tool 6 is transferred to the spindle 23.

Thereafter, in step S16, the tool magazine 11 is moved to the retracted position. In step S17, the spindle 23 is moved to the workpiece machining position P1.
On the other hand, if it is determined NO in step S13, that is, if the tool holder 5 does not exist, it is determined in step S18 that there is no tool holder, and the determination result is displayed on the display device 64. In step S19, the tool holder is mounted (error processing) by the operator.

In FIG. 9, since the tool holder 5 is not attached to the main shaft 23, there is no rise in pressure at time h7 when the clamping operation of the tool holder 5 is performed.
According to the cleaning method of the tapered hole 28a of the spindle device and the tapered shank portion of the tool holder in the machine tool of the first embodiment, the following effects can be obtained.

  (1) In the first embodiment, pressure air is supplied from the pressure air supply source 40 to the air supply passage 44 and the air passage 45 via the air supply pipe 41 and the air supply passages 42 and 43, and the first to first 3 Air was supplied to the gaps G1 and G2 from the air injection holes 46, 47 and 48, and a pressure sensor 50 was provided in the air supply pipe 41. Further, based on the pressure measured by the pressure sensor 50, a presence / absence determining unit 75 for determining the presence / absence of the tapered shank portion 34 of the tool holder 5 with respect to the tapered hole 28a of the main shaft 23 is provided. For this reason, while being able to clean the taper hole 28a and the taper shank part 34, the presence or absence of the tool holder 5 can be determined during the cleaning operation.

  (2) In the first embodiment, the determination reference value PK is set by adding the positive constant Pc of the pressure to the first measurement value PS1 set by the determination reference value setting unit 73. Further, the determination unit 75 compares the newly set second measured value PS2 with the determination reference value PK to determine whether the tool holder 5 is present. Therefore, even if the pressure of the air supplied from the pressure air supply source 40 fluctuates, the determination reference value PK is set based on the first measured value PS1 of the fluctuating air pressure. Presence / absence can be determined with high accuracy.

  (3) In the first embodiment, the time h3 when the tool holder 5 is in the unclamped state is used as the setting reference for the first timing setting unit 72, and the tool is used as the setting reference for the second timing setting unit 74. The start time h7 of the clamping operation of the holder 5 was used. For this reason, it is not necessary to provide a dedicated setting reference, and the software for determining the presence / absence of the tool holder 5 of the control device 51 can be easily created.

  Next, a second embodiment of the present invention will be described with reference to FIGS. Note that in the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in FIG. 12, a two-position, three-port electromagnetic switching valve 81 is connected to the air supply pipe 41 between the pressure air supply source 40 and the on-off valve 49, and the air supply pipe 41 is always connected by a spring. It is held in the first port 81a that communicates. Further, when the electromagnetic switching valve 81 is switched to the second port 81b by an operation signal from the control device 51, the air supply pipe 41 is connected to a bypass passage 83 having a fixed flow control valve 82 for suppressing pressure fluctuation. It has become. In the state where the electromagnetic switching valve 81 is switched to the first port 81a, the air supply pipe 41 functions as a cleaning flow path.
Next, the function of the central processing unit 52 of the control device 51 will be described with reference to FIG.
The central processing unit 52 is provided with a source pressure abnormality determination unit 85 for determining whether or not the source pressure Pg of the pressure air supplied from the pressure air supply source 40 is normal. The original pressure Pg measured based on the original pressure Pg measured by the abnormality determination unit 85, the minimum determination reference value Pgmin and the maximum determination reference value Pgmax for determining the abnormality of the original pressure stored in the RAM 54 in advance. It is determined whether or not Pg is normal. The central processing unit 52 is provided with a clogging determination reference value setting unit 86 for setting a pressure reference value for determining clogging of the first to third air injection holes 46 to 48. A clogging determination unit 87 for determining clogging of the air injection holes 46 to 48 based on the reference value and the measured pressure is provided. Further, in the central processing unit 52, chips are caught between the outer peripheral surface of the tapered shank portion 34 of the tool holder 5, the front end surface of the inner peripheral surface of the tapered hole 28 a of the inner flange 28, and the tool holder 5. A mounting failure determination reference value setting unit 88 is provided for setting a pressure reference value for determining that a mounting failure of the holder 5 has occurred. The central processing unit 52 is provided with a tool attachment failure determination unit 89 for determining attachment failure of the tool holder 5 based on the reference value and the measured pressure.
Next, based on the operation control unit 71 of the control device 51 shown in FIG. 13, refer to the flowcharts of FIGS. 12, 14, and 15 for various abnormality determination operations when the tool holder 5 is replaced in the second embodiment. To explain.

  In FIG. 12, the opening / closing valve 49 is switched from the open port 49a to the closed port 49b by the operation signal from the control device 51, and the electromagnetic switching valve 81 is held in the first port 81a (step S1 in FIG. 14). Thus, the pressure air supply source 40 is activated at time h1 in FIG. 18, and pressure air is supplied to the air supply pipe 41 (step S2 in FIG. 14). Thereafter, the pressure of the air supply pipe 41, that is, the original pressure Pg of the pressure air supply source 40 is measured by the pressure sensor 50 (step S3).

  Next, as shown in step S4, an abnormality in the original pressure Pg measured based on the original pressure Pg measured by the determination unit 85, the preset minimum determination reference value Pgmin, and the maximum determination reference value Pgmax. Is determined. If NO in step S4, that is, if it is determined that the original pressure Pg is out of the reference value Pgmin or Pgmax, an abnormality in the original pressure is notified to the display device 64 in step S5, and the operator presses the pressure in step S6. Error processing such as repair of the air supply source 40 is performed. On the other hand, if YES in step S4, that is, if the original pressure Pg is determined to be normal, the original pressure Pg measured by the determination reference value setting unit 86 and the ROM 53 previously stored in FIG. The threshold value is calculated based on a linear function (Pt = a · Pg + b) of the graph shown, and the calculated value (Pt) is used as a determination reference value Pt for determining whether the air injection holes 46 to 48 are clogged. Is remembered.

  Next, based on the original pressure Pg measured by the mounting failure determination reference value setting unit 88 in step S8 and the linear function (Pm = a · Pg + b) shown in FIG. A determination reference value Pm for presence / absence determination is calculated, and this determination reference value Pm is stored in the RAM 54.

  Thereafter, as shown in step S9, at time h2 shown in FIG. 18, the on-off valve 49 shown in FIG. 12 is switched from the closed port 49b to the open port 49a. As a result, as shown in step S10, the first to third air injections are performed from the pressure air supply source 40 through the air supply pipe 41 functioning as a cleaning flow path when the tool holder 5 is not mounted in the tapered hole 28a. The holes 46 to 48 are supplied. Next, in step S11, at time h3 shown in FIG. 18, the electromagnetic switching valve 81 is switched to the second port 81b, and the pressure fluctuation is suppressed from the pressure air supply source 40 through the bypass passage 83 and the fixed flow control valve 82. The air thus supplied is supplied to the first to third air injection holes 46 to 48. In step S12, the first measurement value PS1 is set at time h4 shown in FIG. 18 in the same manner as the setting operation of the first measurement value PS1 in the first embodiment, and in step S13, based on the first measurement value PS1. A determination reference value PK (= PS1 + Pc) for determining the presence or absence of the tool holder is set. In this state, as shown in step S14, the pressure of the air supply pipe 41 is measured by the pressure sensor 50, and the measured pressure Pe indicated by the pressure curve LP is input to the control device 51 from time h4 in FIG.

  Next, in step S15 shown in FIG. 15, it is determined whether or not the measured pressure Pe measured at time h4 shown in FIG. 18 when the tool holder 5 is not mounted is larger than the determination reference value Pt. That is, when the measured pressure Pe is higher than the determination reference value Pt for nozzle clogging, as indicated by the pressure curve LP1 indicated by the two-dot chain line in FIG. 18, the air injection holes 46 to 48 in step S16. At least one of the clogs (abnormality) is notified by the display device 64, and an operation for removing the clogs is performed by the operator in step S17. If YES in step S15, that is, if it is determined that the measured pressure Pe is smaller than the determination reference value Pt, in step S18, the electromagnetic switching valve 81 is switched to the first port 81a at time h5 shown in FIG. As indicated by the curve LP, the measured pressure Pe increases. Next, at time h6 in FIG. 18, the taper shank portion 34 of the tool holder 5 is fitted into the taper hole 28a of the main shaft with predetermined gaps G1 and G2. In this state, the taper hole 28a and the taper shank portion 34 are cleaned by the air injected from the air injection holes 46 to 48. Next, in step S19, the tapered shank portion 34 of the tool holder 5 is clamped in the tapered hole 28a. Thereafter, as shown in step S20, the second measurement value PS2 measured at time h7 in FIG. 18 is output to the control device 51, and it is determined whether or not the second measurement value PS2 is larger than the determination reference value PK. If the determination result is NO, that is, if the second measurement value PS2 is lower than the determination reference value PK for the presence / absence of the nozzle as shown in the pressure curve LP2 indicated by the two-dot chain line in FIG. 18, there is no tool holder in step S22. (Abnormal) is notified by the display device 64, and an error processing operation for attaching the tool holder is performed by the operator in step S23.

  If YES in step S21, that is, if the second measurement value PS2 at time h7 is determined to be larger than the determination reference value PK as indicated by the pressure curve LP3, the second measurement value PS2 is determined to be the determination reference value in step S24. It is determined whether or not it is greater than Pm, and it is determined as NO, that is, the second measured value PS2 at time h7 is based on the chip chewing determination reference value Pm as shown by the pressure curve LP4 indicated by the two-dot chain line in FIG. If it is lower, in step S25, the tool holder mounting failure (abnormality) is notified by the display device 64, and in step S26, error handling operations such as removal of chips bitten by the operator are performed.

  If YES in step S24, that is, if the second measured value PS2 at time h7 is determined to be greater than the determination reference value Pm as indicated by the pressure curve LP3 in FIG. 18, the tool holder is normally mounted in step S27. This has been notified by the display device 64. Thereafter, operations in steps S28 to S30 similar to steps S15 to S17 in FIG. 7 are performed.

The effect of the abnormality determination device for mounting the tool holder 5 on the spindle device of the second embodiment will be described.
(1) In the second embodiment, the source pressure Pg supplied from the pressure air supply source 40 is determined to be abnormal by the source pressure abnormality determination unit 85 provided in the control device 51. Therefore, the source pressure Pg is abnormal. In this state, the taper shank portion 34 of the tool holder 5 is cleaned with air, the clogging of the first to third air injection holes 46 to 48 is determined, the presence / absence of the tool holder 5 is determined, and the tool holder is formed by biting the chips. 5 is not determined, and various determination operations can be performed appropriately.

  (2) In the second embodiment, the determination reference value setting unit 86 and the determination unit 87 provided in the control device 51 can determine whether or not the first to third air injection holes 46 to 48 are clogged. The cleaning operation of the tool holder 5 with air is not performed in a clogged state, and the cleaning operation can be performed appropriately.

  (3) In the second embodiment, the mounting failure determination reference value setting unit 88 and the tool mounting failure determination unit 89 provided in the control device 51 have a mounting failure of the tool holder 5 due to chipping or the like. The tool holder 5 is not clamped to the main shaft as it is, and therefore the tool holder 5 is properly mounted on the main shaft 23, and the workpiece machining accuracy can be improved.

In addition, you may change each embodiment mentioned above as follows.
In each of the above embodiments, the spindle device 4 is reciprocated in the Z-axis direction together with the column 3, but a quill movement type configuration in which only the spindle device 4 is reciprocated in the Z-axis direction with respect to the column 3 is also possible. Good.

  ・ The tool holder is grasped by a linear tool magazine installed in a straight line at a predetermined position, and the spindle device 4 is advanced and retracted, and the tool holder 5 is detachably mounted. For example, the tool holder 5 may be moved to the tool change position by turning the exchange arm, and the tool changer may be embodied in a tool changer of a type in which the tool holder 5 is attached or detached.

In the above embodiment, the clamp mechanism K of the so-called KM holder is embodied. However, the clamp mechanism of the so-called BT holder or HSK holder may be embodied.
The air injection holes 46 may be formed at a plurality of locations in the width direction of the front end surface of the inner flange 28. In this case, the rear end surface 5c of the main body of the tool holder 5 can be efficiently cleaned.

  -Judgment of clogging of the air injection hole and presence / absence of the tool holder 5 based on the flow rate measurement value from a flow rate sensor as a flow rate measuring means for detecting the air flow rate by the same operation as the above-described determination operation by air pressure It is also possible to determine whether or not the tool holder 5 is poorly mounted by biting the chips.

The aforementioned setting timing of the determination reference values PK, Pt, Pm may be changed to another timing.
The maximum determination reference value Pgmax and the minimum determination reference value Pgmin in step S4 of FIG. 14 of the second embodiment may be set in advance based on the measured value of the actual pressure Pg actually measured.

  The electromagnetic switching valve 81, the fixed flow control valve 82, and the bypass passage 83 of the second embodiment may be omitted. In this case, since the time for switching the air flow path can be omitted, the pressure measurement time can be shortened, and various abnormality determination operations can be performed quickly.

  A pressure measurement / reference determination device having functions of the pressure sensor 50, the determination reference value setting unit 73, and the determination unit 75 is provided, and the central processing unit 52 performs various operations based on the determination results of the pressure measurement / reference determination device. The operation signal may be output to the related device.

The principal part expanded sectional view which shows the unclamped state of the tool holder which shows 1st Embodiment which actualized the abnormality determination apparatus at the time of the tool holder attachment to the spindle apparatus in the machine tool of this invention. The principal part expanded sectional view which shows the clamped state of the tool holder of a spindle apparatus similarly. The expanded sectional view which shows the clamped state of the tool holder of the front half part of a main shaft apparatus. The front sectional view which looked at the principal axis of the principal axis device from the direction of an axis. The block circuit diagram which shows the control system of a machine tool. The flowchart for demonstrating the tool exchange operation | movement of a machine tool. The flowchart for demonstrating the tool exchange operation | movement of a machine tool. The graph which shows the pressure curve of the air in the state with which the tool holder was mounted | worn with the main axis | shaft. The graph which shows the pressure curve of the air in the state in which the tool holder is not mounted | worn with the main axis | shaft. The right view which shows the whole machine tool. Explanatory drawing of the tool exchange operation | movement of FIG. The circuit diagram which shows the air supply path | route which shows 2nd Embodiment which actualized the abnormality determination apparatus at the time of the tool holder mounting | wearing to the spindle apparatus in the machine tool of this invention. The block circuit diagram which shows the control system of a machine tool. The flowchart for demonstrating the tool exchange operation | movement of a machine tool. The flowchart for demonstrating the tool exchange operation | movement of a machine tool. The graph which shows the relationship between a source pressure and a criterion value. The graph which shows the relationship between a source pressure and a criterion value. The graph which shows the relationship between time and measurement pressure.

Explanation of symbols

  h, h1, h2, h3, h4, h5, h6, h7, h8 ... time, G1, G2 ... gap, Pb, PK, Pm ... judgment reference value, Pg ... original pressure, PS1 ... first measured value, PS2 ... 2nd measurement value, Pgmax ... highest judgment reference value, Pgmin ... lowest judgment reference value, 4 ... spindle device, 5 ... tool holder, 21 ... spindle head, 23 ... spindle, 28a ... taper hole, 34 ... taper shank part, 40 ... pressure air supply source, 42, 43, 44 ... air supply passage, 46-48 ... air injection hole, 72 ... first timing setting unit, 73 ... tool holder presence / absence determination reference value setting unit, 74 ... second timing setting unit 75 ... Tool holder presence / absence determination unit, 85 ... Source pressure abnormality determination unit, 86 ... Clogging determination reference value setting unit, 87 ... Clogging determination unit, 88 ... Mounting failure determination reference value setting unit, 89 ... Tool mounting failure determination Department.

Claims (12)

A taper shank portion of a tool holder is detachably mounted in a taper hole at a tip portion of a main shaft rotatably supported by a main shaft head of the main shaft device, and cleaning air for the taper shank portion is supplied to the taper hole with respect to the main shaft. In a machine tool provided with an air supply hole for supplying, and provided with an air supply passage for supplying cleaning air from a pressure air supply source to the air injection hole,
The pressure or flow rate of the air supplied from the pressure air supply source to the air supply passage is measured, the determination reference value set according to the measurement value and stored in the storage medium, and the newly measured pressure or An abnormality determination method at the time of mounting a tool holder on a spindle device in a machine tool, wherein the presence or absence of the tool holder is determined based on a measured value of a flow rate. 2. The pressure or flow rate of claim 1 at a predetermined time after air injection is started from the air injection hole in a state where the taper shank portion of the tool holder has a predetermined gap with respect to the taper hole. 1 measurement value is measured, and a determination reference value with a positive constant added to the first measurement value is set. At a predetermined time after the determination reference value is set, the tapered shank portion is formed in the tapered hole. A spindle in a machine tool that measures a second measurement value of pressure or flow rate in a clamped state and compares the second measurement value with the determination reference value to determine the presence or absence of a tool holder. An abnormality determination method when the tool holder is mounted on the apparatus. 3. The eye according to claim 1, wherein the pressure or flow rate of air supplied to the air injection hole is measured in a state where the air injection hole is opened, and is set according to the measured value and stored in a storage medium. It is characterized by determining the presence or absence of clogging of the air injection hole based on a determination reference value for clogging determination and a newly measured pressure or flow rate in a state where the air injection hole is opened. Abnormality determination method when a tool holder is mounted on a spindle device in a machine tool. In any one of Claims 1-3, in the state by which the taper shank part of the said tool holder was clamped by the said taper hole, the pressure or flow volume of the air of the said air injection hole was measured, and according to this measured value The determination reference value for determining the mounting failure that is set and stored in the storage medium, and the measured value of the pressure or flow rate that is newly measured in a state where the tapered shank portion of the tool holder is clamped in the tapered hole. An abnormality determination method at the time of mounting a tool holder on a spindle device in a machine tool, wherein the presence or absence of mounting failure of the taper shank portion with respect to the tapered hole is determined based on. 5. The source pressure of the pressure air supply source is measured in a state where the supply of air to the air injection hole is shut off, and the measured value of the source pressure is stored in advance in a storage medium. An abnormality determination method at the time of mounting a tool holder on a spindle device in a machine tool, wherein presence / absence of abnormality of the original pressure is determined based on a stored minimum determination reference value and maximum determination reference value for a main pressure. A taper shank portion of a tool holder is detachably mounted in a taper hole at a tip portion of a main shaft rotatably supported by a main shaft head of the main shaft device, and cleaning air for the taper shank portion is supplied to the taper hole with respect to the main shaft. In a machine tool provided with an air supply hole for supplying, and provided with an air supply passage for supplying cleaning air from a pressure air supply source to the air injection hole,
The air supply passage is provided with pressure measuring means or flow rate measuring means for measuring the pressure or flow rate of air, and is set according to the pressure measurement value or flow rate measurement value from the pressure measurement means or flow rate measurement means and the measurement value. A tool holder presence / absence determining unit for determining the presence / absence of the tool holder based on the determination reference value stored in the storage medium and the newly measured pressure or flow rate measurement value is provided. An abnormality determination device when a tool holder is mounted on a spindle device in a machine. The determination unit according to claim 6, wherein the first timing setting unit is configured to start air injection from the air injection hole in a state where the taper shank portion of the tool holder has a predetermined gap with respect to the taper hole. A determination reference value setting unit for setting a determination reference value obtained by adding a positive constant of pressure or flow rate to the first measurement value of the measured pressure or flow rate at a predetermined time set by After the setting, the second measured value of the pressure or flow rate newly measured in a state where the tapered shank portion is clamped in the tapered hole at the predetermined time set by the second timing setting unit, and the determination A tool holder presence / absence judging unit for judging the presence / absence of a tool holder by comparing with a reference value and determining whether there is an abnormality when the tool holder is mounted on a spindle device in a machine tool Apparatus. 8. The pressure measuring means or the flow rate measuring device according to claim 7, wherein the first timing setting unit uses a time when the tool holder is unclamped from the spindle as a first timing setting reference, and a predetermined time elapses from the setting reference. A tool holder is mounted on a spindle device in a machine tool, characterized in that a time at which a pressure measurement value or a flow measurement value measured by means is substantially smoothed and constant is set as a first timing. Abnormality judgment device for time. 8. The second timing setting unit according to claim 7, wherein the second timing setting unit sets, as a second timing, a time at which the tool holder is clamped to the spindle, and sets a time after a predetermined time has elapsed from the setting reference as a second timing. An abnormality determination device when a tool holder is mounted on a spindle device in a machine tool, characterized in that the device is configured as follows. In any one of Claims 6-9, the measured value of the original pressure of the said pressure air supply source measured in the state which interrupted | blocked the supply of the air to the said air injection hole, and the former memorize | stored in the storage medium A main pressure abnormality determining unit that determines whether or not the original pressure is abnormal based on a minimum determination reference value and a maximum determination reference value for pressure when the tool holder is mounted on the spindle device in the machine tool, Abnormality judgment device. In any one of Claims 6-10, the abnormality determination reference value setting part which determines the clogging abnormality of the said air injection hole, and the state of the air supplied to this air injection hole in the state which opened the air injection hole A measured value of pressure or flow rate, a judgment reference value for clogging judgment set according to the measured value and stored in a storage medium, and a newly measured pressure or An abnormality determination device at the time of mounting a tool holder on a spindle device in a machine tool, comprising: an abnormality determination unit that determines whether the air injection hole is clogged based on a measured value of a flow rate. In any one of Claims 6-11, the determination reference value setting part which sets the reference value of the pressure or flow rate which determines the mounting | wearing defect of the said tool holder with respect to the said taper hole, and the taper shank part of a tool holder in a taper hole In the clamped state, a measured value of the pressure or flow rate of air supplied to the air injection hole, a determination reference value for determining a mounting failure set according to the measured value and stored in the storage medium, Tool mounting for determining whether or not there is a mounting failure of the taper shank to the taper hole based on the newly measured pressure or flow rate measured in a state where the taper shank of the tool holder is clamped in the taper hole An abnormality determination device when a tool holder is mounted on a spindle device in a machine tool, comprising: a defect determination unit.

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