阅读说明：本技术 机床 (Machine tool ) 是由 饭山浩司 于 2019-07-17 设计创作，主要内容包括：机床(1)具备：保持部(7),用于保持工具(T)；保持机构(10),其进行将工具(T)保持在保持部(7)的保持动作及从保持部(7)释放工具(T)的释放动作；控制部(20),用于使保持机构(10)执行保持动作及释放动作；手动操作部(18),用于将手动操作信号输入至控制部(20)；以及犹豫状态报知部(21)。控制部(20)从手动操作部(18)接收到操作信号后,经过预先规定的犹豫时间之后,将与操作信号对应的驱动信号发送给保持机构(10)使之动作。犹豫状态报知部(21)具备输出人能感知到的能量的能量输出设备(22),基于从控制部接收的信息来识别犹豫时间的剩余时间,通过使能量输出设备(22)的输出状态发生变化来报知与剩余时间对应的信息。(A machine tool (1) is provided with: a holding section (7) for holding a tool (T); a holding mechanism (10) that performs a holding operation for holding the tool (T) in the holding portion (7) and a releasing operation for releasing the tool (T) from the holding portion (7); a control unit (20) for causing the holding mechanism (10) to perform a holding operation and a releasing operation; a manual operation unit (18) for inputting a manual operation signal to the control unit (20); and a hesitation state notification unit (21). The control unit (20) receives the operation signal from the manual operation unit (18), and after a predetermined time, transmits a drive signal corresponding to the operation signal to the holding mechanism (10) to operate the holding mechanism. The hesitation state notification unit (21) is provided with an energy output device (22) that outputs energy that can be perceived by a person, identifies the remaining time of the hesitation time on the basis of information received from the control unit, and notifies information corresponding to the remaining time by changing the output state of the energy output device (22).)

1. A machine tool is provided with the following mechanisms:

a holding portion for holding a tool;

a holding mechanism that performs a holding operation of holding the tool in the holding portion and a releasing operation of releasing the held tool;

a control unit for driving the holding mechanism to perform the holding operation and the releasing operation; and

a manual operation unit configured to input an operation signal for causing the holding mechanism to perform the holding operation and the releasing operation to the control unit;

the control unit is configured to: after a predetermined hesitation time elapses after receiving the operation signal input from the manual operation unit, transmitting a drive signal corresponding to the received operation signal to the holding mechanism, and causing the holding mechanism to execute an operation corresponding to the operation signal; the machine tool is characterized in that:

the energy output device includes an energy output device that outputs energy that can be perceived by a person to an external space, and is provided with a hesitation state notification unit that recognizes a remaining time of the hesitation time based on information received from the control unit, and notifies information corresponding to the recognized remaining time by changing an output state of the energy output by the energy output device.

2. The machine tool of claim 1, wherein:

the hesitation state notification unit includes a lamp that irradiates light as the energy output device, and is configured to notify information corresponding to the remaining time by alternately turning on and off the lamp that irradiates light, and to shorten an on/off alternation interval of the lamp as the remaining time becomes shorter.

3. The machine tool of claim 1, wherein:

the hesitation state notification unit includes a lamp that irradiates light as the energy output device, and is configured to notify information corresponding to the remaining time based on an intensity of the light irradiated from the lamp, and decrease or increase the intensity of the irradiated light as the remaining time becomes shorter.

4. The machine tool of claim 1, wherein:

the hesitation state notification unit includes a plurality of lamps that irradiate light as the energy output device, and is configured to notify information corresponding to the remaining time by lighting a preset lamp in accordance with the remaining time.

5. The machine tool of claim 1, wherein:

the hesitation state notification unit includes a speaker that outputs a sound as the energy output device, and is configured to notify information corresponding to the remaining time using the sound output from the speaker.

6. The machine tool of claim 5, wherein:

the hesitation state notification unit is configured to: sound is intermittently output from the speaker, and as the remaining time becomes shorter, an output interval of sound is made shorter.

7. The machine tool of claim 5, wherein:

the hesitation state notification unit is configured to: outputting a voice from the speaker, and reporting the remaining time by counting down in the voice.

8. The machine tool of any one of claims 1 to 7, wherein:

the manual operation unit is configured to input a cancel signal for canceling a most recently input operation signal to the control unit,

the control unit is configured to: when a cancel signal is input from the manual operation unit before the dead time elapses, transmission of a drive signal corresponding to an operation signal input before the cancel signal to the holding mechanism is stopped.

Technical Field

The present invention relates to a machine tool having a holding portion for holding a tool, and configured to be able to manually attach and detach the tool to and from the holding portion.

Background

For example, a machine tool such as a machining center (machining center) is configured to: a tool is held by a spindle, and the spindle and an appropriate table on which a workpiece is mounted are relatively moved in a three-dimensional space in a state where the spindle is rotated by a spindle motor, thereby machining the workpiece.

The spindle is provided with a holding mechanism for holding a tool in a holding hole of the spindle, and the holding mechanism is controlled by an appropriate control device such as a numerical control device and performs a holding operation for holding the tool and a releasing operation for releasing the held tool.

In addition, such machine tools are typically configured to manually mount or dismount the tool to or from the spindle. For example, an operation button for performing a mounting and demounting operation is provided in the vicinity of a mounting and demounting position set as a position for manually mounting and demounting a tool, and when an operator operates the operation button, a signal corresponding to the operation is transmitted from the operation button to the control device, and the holding mechanism is driven under the control of the control device, so that the holding mechanism performs the mounting and demounting of the tool with respect to the spindle.

Specifically, the operator moves the spindle to the loading/unloading position, and then operates an operation button for loading/unloading in a state where the tool is held, whereby a loading/unloading signal is transmitted from the operation button to the control device, and the holding mechanism performs a release operation under the control of the control device. Thereby, the tool held on the spindle is released, and the operator removes the released tool from the spindle.

On the other hand, when the tool is mounted on the spindle, similarly, after the operator moves the spindle to the above-described mounting/dismounting position, the operator operates the operation button for mounting in a state where the tool is inserted into the holding hole of the spindle, whereby a mounting signal is transmitted from the operation button to the control device, and the holding mechanism performs a holding operation under the control of the control device, whereby the tool is mounted in the holding hole of the spindle.

Further, tools used in machine tools include relatively light tools such as drills and end mills, and relatively heavy tools such as face mills and boring bars. Further, in the case where such a heavy tool is manually removed from the spindle, if the holding mechanism performs the releasing operation immediately after the operator operates the operation button for removal, the tool may be released before the operator has sufficiently made a posture for receiving the tool, and in this case, the operator may fail to catch the tool, causing a problem that the tool is dropped. In particular, in the case of a vertical machine tool, the operator is liable to drop the tool.

Further, conventionally, there is a machine tool in which a through hole opened at a tip end of a tool is formed in the tool, and a coolant is ejected from an opening portion of the tool through the through hole, but in general, a spring body is mounted in a holding hole of a spindle so that a rear end portion of the tool is brought into close contact with a coolant supply portion. Therefore, when the holding mechanism is operated to release the tool, the tool flies out from the spindle by the biasing force of the spring body, and even if the weight of the tool is relatively light, the operator may not catch the tool and the tool may drop.

On the other hand, when the tool is mounted on the spindle, if the tool is heavy, the operator may manipulate the operation button for mounting in a state where the tool is not securely inserted into the holding hole of the spindle. Such a problem is likely to occur particularly in the case of a vertical machine tool.

In order to solve such a problem, an electric discharge machining apparatus (machine tool) disclosed in patent document 1 has been proposed. That is, the electric discharge machining apparatus includes: a timer for measuring an elapsed time set by a user as a support preparation period of the object to be gripped after detecting an operation of performing gripping (holding) or releasing (releasing); and a gripper control unit that, when the timer has timed out, causes the gripping device to execute an operation corresponding to the detected operation.

According to this electric discharge machining apparatus, even if the object to be gripped is heavy and cannot be supported by one hand, the operator can hold the object to be gripped with both hands during the countdown of the timer, and the object to be gripped released from the gripping device can be prevented from falling or from being gripped in the gripping device in an incomplete state.

Background of the invention

Patent document

Patent document 1: japanese patent No. 5128013

Disclosure of Invention

Problems to be solved by the invention

However, in the conventional machine tool including the timer and the jig control unit disclosed in patent document 1, the problem that the operator cannot perform the operation in a sufficiently prepared posture when the tool is attached to or detached from the spindle has not been solved yet.

That is, by executing the mounting and demounting operation corresponding to the manual operation after the time set by the timer has elapsed after the manual operation by the operator, the operator has a sufficient time to cope with the mounting and demounting operation, but the operator can only grasp the timing by feel when the mounting and demounting operation is executed specifically, and therefore, the mounting and demounting operation cannot be dealt with in a sufficiently prepared posture.

For example, in the case of removing a tool from a spindle, if the operator has a sufficient time to hesitate after operating the operation button, the operator can take a posture in which the tool to be removed is sufficiently held, but if the time of release is not clear, the operator cannot maintain the preparatory posture in a state in which the operator keeps a sense of tension. Therefore, the operator suddenly releases the tool, and as a result, the operator cannot appropriately respond to the tool release operation, and the operator suddenly comes to have a burden, which causes the posture to be disturbed or the tool to be dropped. The same is true when mounting the tool to the spindle.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a machine tool in which, when a tool is manually attached to or detached from a spindle, an operator can objectively predict or recognize a timing at which a loading/unloading operation is performed by the operation.

Means for solving the problems

The present invention for solving the above-described problems relates to a machine tool including:

a holding portion for holding a tool;

a holding mechanism that performs a holding operation of holding the tool in the holding portion and a releasing operation of releasing the held tool;

a control unit for driving the holding mechanism to perform the holding operation and the releasing operation; and

a manual operation unit configured to input an operation signal for causing the holding mechanism to perform the holding operation and the releasing operation to the control unit;

the control unit is configured to: transmitting a drive signal corresponding to the received operation signal to the holding means after a predetermined hesitation time has elapsed after receiving the operation signal input from the manual operation unit, and causing the holding means to execute an operation corresponding to the operation signal; and is

The machine tool includes an energy output device that outputs energy that can be perceived by a person to an external space, and is provided with a hesitation state notification unit that recognizes a remaining time of the hesitation time based on information received from the control unit, and notifies information corresponding to the recognized remaining time by changing an output state of the energy output by the energy output device.

According to this machine tool, when the operator operates the manual operation portion in order to manually attach or detach the tool to or from the holding portion, a corresponding operation signal is transmitted from the manual operation portion to the control portion. After a predetermined hesitation time elapses after the operation signal input from the manual operation unit is received, the control unit transmits a drive signal corresponding to the received operation signal to the holding mechanism, and causes the holding mechanism to execute an operation corresponding to the operation signal.

On the other hand, the hesitation state notification unit identifies the remaining time of the hesitation time based on the information received from the control unit, and notifies information corresponding to the identified remaining time by changing the output state of the energy output by the energy output device. In this way, the operator can objectively predict or recognize the remaining time until the holding mechanism executes the operation based on the change in the output state of the energy output from the energy output device, and can make a posture corresponding to the loading and unloading operation. Therefore, the operator can reliably hold the tool removed from the holding portion when removing the tool from the holding portion, and can accurately attach the tool to the holding portion when attaching the tool to the holding portion.

The remaining time may be recognized by directly receiving information on the remaining time of the dead time from the control unit, or may be recognized by receiving an operation signal from the control unit and calculating the remaining time of the dead time by holding the information on the dead time set in the control unit, when the operation signal is input from the manual operation unit.

In the present invention, the hesitation state notification unit may employ the following embodiment: the energy output device is provided with a lamp for irradiating light, and is configured to notify information corresponding to the remaining time by alternately turning on and off the lamp for irradiating light, and to shorten the on and off alternation interval of the lamp as the remaining time becomes shorter. In such an embodiment, the operator can objectively predict or recognize the remaining time until the holding mechanism performs the operation by recognizing the on/off alternation interval of the lamp.

In the present invention, the hesitation state notification unit may employ the following example: the energy output device includes a lamp for irradiating light, and is configured to notify information corresponding to the remaining time of the dead time based on the intensity of the light irradiated from the lamp, and to decrease or increase the intensity of the irradiated light as the remaining time becomes shorter. In such an embodiment, the operator can objectively predict or identify the time remaining until the holding mechanism performs an action by identifying the intensity of the lamp that is reversed.

In the above embodiments, as the lamp of the energy output device, a lamp for illuminating the machining area of the machine tool may be applied.

In the present invention, the hesitation state notification unit may employ the following example: the energy output device includes a plurality of lamps for irradiating light, and is configured to notify information corresponding to the remaining time of the dead time by lighting a preset lamp in accordance with the remaining time of the dead time. In such an embodiment, the operator can objectively predict or recognize the remaining time until the holding mechanism performs the operation by confirming the lamp that is turned on. Further, the following embodiments can be provided: the plurality of lamps are arranged in a row, and the lamps are sequentially turned on according to the remaining time. Alternatively, the following embodiments may be provided: the plurality of lamps are made to emit different light colors, and the lamps of the colors corresponding to the remaining time are turned on.

In the present invention, the hesitation state notification unit may employ the following example: the energy output device includes a speaker that outputs a sound, and is configured to notify information corresponding to the remaining time of the dead time using the sound output from the speaker. In such an embodiment, the operator can objectively predict or recognize the remaining time until the holding mechanism performs the operation based on the sound output from the speaker.

In the present invention, the hesitation state notification unit may employ the following example: the speaker is configured to intermittently output sounds, and the output interval of the sounds is shortened as the remaining time of the dead time becomes shorter. In such an embodiment, the operator can objectively predict or recognize the remaining time until the holding mechanism performs the operation by recognizing the interval of the sound intermittently output from the speaker.

In the present invention, the hesitation state notification unit may employ the following example: the voice is outputted from the speaker, and the remaining time of the dead time is reported by a voice countdown. In such an embodiment, the operator can objectively predict or recognize the remaining time until the holding mechanism performs the operation by recognizing the count output in voice form from the speaker.

In the machine tool according to each of the above embodiments, it is preferable that the manual operation unit is configured to input a cancel signal for canceling a most recently input operation signal to the control unit,

the control unit is configured to, when a cancel signal is input from the manual operation unit before the dead time elapses, stop transmission of a drive signal corresponding to an operation signal input before the cancel signal to the holding mechanism.

As described above, in the machine tool according to each of the above embodiments, the operator can objectively predict or recognize the remaining time until the holding mechanism executes the operation, but there is a case where the posture corresponding to the manual operation cannot be sufficiently made by some reason before the holding mechanism executes the operation on the operator side. In this case, if the holding mechanism performs an operation corresponding to a manual operation, as a result, there may be a situation where it is impossible to attach the tool to the holding portion with high accuracy or to reliably hold the tool detached from the holding portion. Therefore, when the operator cannot make a sufficient posture, the cancellation signal is input from the manual operation unit before the dead time elapses, and the operation signal input before the cancellation signal is cancelled, whereby the above-described problem can be prevented from occurring.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the operator can objectively predict or recognize the remaining time until the holding mechanism executes the operation based on the change in the output state of the energy output from the energy output device, and can make the posture corresponding to the loading and unloading operation. Therefore, when the operator removes the tool from the holding portion, the operator can reliably hold the tool removed from the holding portion, and when the operator attaches the tool to the holding portion, the operator can attach the tool to the holding portion with high accuracy.

Drawings

Fig. 1 is a perspective view showing a machine tool according to an embodiment of the present invention.

Fig. 2 is an explanatory diagram showing a schematic configuration of the machine tool of the present embodiment.

Fig. 3 is a front view showing an energy output apparatus of another embodiment of the present invention.

Fig. 4 is a front view showing an energy output apparatus of a further embodiment of the present invention.

Detailed Description

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

As shown in fig. 1, the machine tool 1 of the present embodiment is a vertical machining center, and includes a machine base 2 shown in fig. 1, a column 3 erected on the machine base 2, a saddle 4 provided movably in the Y-axis direction on the machine base 2, a table 5 provided movably in the X-axis direction on the saddle 4, a spindle head 6 supported movably in the Z-axis direction on the column 3, and a manual operation unit 18, a numerical control device 20, a hesitation state notification unit 21, and the like shown in fig. 2. The X, Y, and Z axes are moving axes orthogonal to each other, and the Z axis is a vertical axis.

As shown in fig. 2, the spindle 7 is held by the spindle head 6, and the spindle 7 is rotatable about a vertical axis. A tapered mounting hole (holding hole) 8 that opens at an end surface of the spindle 7 is formed at a central tip end portion (lower end portion) of the spindle 7, and the spindle 7 functions as a holding portion for holding a tool T, and the tool T is mounted in the mounting hole 8.

A through hole 9 that extends to the mounting hole 8 is formed in the center of the spindle 7, and a tubular outer tube member 12 inserted with its lower end facing the mounting hole 8, a collet 11 inserted into the lower end of the outer tube member 12, a tension rod (draw bar)13 inserted into the outer tube member 12 with its lower end engaged with the collet 11, a coil spring 14 externally fitted to the tension rod 13, and the like are disposed in the through hole 9.

The collet 11, the outer cylindrical member 12, the rod 13, and the coil spring 14 constitute a part of the holding mechanism 10, and the holding mechanism 10 is provided with a hydraulic cylinder 15 connected to the rod 13, a pressure oil supply source 16 for supplying pressure oil to the hydraulic cylinder 15, and a switching valve 17 for switching supply and stop of pressure oil from the pressure oil supply source 16 to the hydraulic cylinder 15.

The coil spring 14 pushes the pull rod 13 to be pulled backward (upward), and when the supply of the pressurized oil to the hydraulic cylinder 15 is stopped by the switching action of the switching valve 17, the pull rod 13 is pulled upward by the pushing action of the coil spring 14, whereby the collet 11 is pulled upward together with the pull rod 13, and the collet 11 is closed. The above operation is the holding operation of the holding mechanism 10.

On the other hand, when pressurized oil is supplied to the hydraulic cylinder 15 by the switching action of the switching valve 17, the hydraulic cylinder 15 moves the pull rod 13 forward (downward) against the urging force of the coil spring 14, and the collet 11 moves downward together with the pull rod 13, and the collet 11 opens. The above operation is the releasing operation of the holding mechanism 10.

In this way, if the tool T is inserted into the mounting hole 8 of the spindle 7 in a state where the holding mechanism 10 is in the release state, that is, in a state where the hydraulic oil is supplied to the hydraulic cylinder 15, the pull rod 13 and the collet 11 move downward, and the collet 11 is opened, the pull bolt (pull stud) Ta of the tool T is inserted into the collet 11.

Next, the holding mechanism 10 is switched to stop the supply of the pressurized oil to the hydraulic cylinder 15, and the pull rod 13 and the collet 11 are moved upward by the urging force of the coil spring 14, so that the collet 11 is closed, the pull bolt Ta of the tool T is gripped by the collet 11, and the tool T is pulled into the mounting hole 8. Thereby, the tool T is attached to the spindle 7.

On the other hand, the holding mechanism 10 is caused to perform a releasing operation, that is, the switching valve 17 is switched to supply the hydraulic oil to the hydraulic cylinder 15, the pull rod 13 and the collet 11 are moved downward against the urging force of the coil spring 14, and at this time, the collet 11 is opened, whereby the tool T is released from being gripped by the collet 11, and the tool T can be pulled out from the mounting hole 8.

The holding operation and the releasing operation of the holding mechanism 10 are controlled by the manual operation unit 18 and the numerical control device 20. The manual operation unit 18 is a device into which an operation signal for causing the holding mechanism 10 to perform the holding operation and the releasing operation and a signal (cancel signal) for canceling the input operation signal are input, and in this example, the manual operation unit 18 includes an attachment button for performing the holding operation, a removal button for performing the releasing operation, and a cancel button for canceling. The manual operation portion 18 is disposed at a position operable when an operator manually attaches the tool T to the spindle 7 or removes the tool T from the spindle 7.

The numerical control device 20 is a control device that controls a feed device (not shown), a spindle motor (not shown), and the like of the machine tool 1, and when receiving an operation signal from the manual operation unit 18, transmits a signal (reception signal) indicating that the operation signal has been received to a notification control unit 23 described below, counts an elapsed time from when the operation signal is received, and when the elapsed time reaches a preset hesitation time, that is, after the preset hesitation time has elapsed, transmits a drive signal corresponding to the received operation signal to the switching valve 17 of the holding mechanism 10, and operates the switching valve 17.

Specifically, when a hold (operation) signal (attachment signal) is input from the manual operation unit 18, the numerical control device 20 sends a stop signal (drive signal) to the switching valve 17 after a lapse of a dead time, and stops the supply of the pressurized oil to the hydraulic cylinder 15. On the other hand, when a release (operation) signal (release signal) is input from the manual operation unit 18, the numerical control device 20 transmits a signal (drive signal) for supply to the switching valve 17 after the elapse of a dead time, and supplies the pressurized oil to the hydraulic cylinder 15.

When the cancel signal is received from the manual operation unit 18 after the operation signal (the attachment signal or the detachment signal) is received from the manual operation unit 18 and before the dead time elapses, the numerical control device 20 stops the transmission of the drive signal corresponding to the operation signal received before to the switching valve 17.

The hesitation state notification unit 21 includes: a lamp 22 provided near the lower end of the spindle head 7 so as to be visible to an operator when manually mounting or dismounting the tool T to or from the spindle 7; and an alarm control unit 23 for controlling the lighting state of the lamp 22.

The notification control unit 23 turns on the lamp 22 alternately at preset time intervals when receiving the reception signal from the numerical control device 20, and then the notification control unit 23 turns on and off the lamp 22 alternately so that the time intervals become shorter as the recognized remaining time becomes shorter while recognizing the remaining time of the dead time, and turns off the lamp 22 after the dead time elapses.

Further, as a method of shortening the time interval between the on and off alternation, a stepwise shortening or a continuous shortening may be employed, but the stepwise shortening makes it easier for the operator to grasp the remaining time. As a method for recognizing the remaining time by the notification control unit 23, an example may be adopted in which the information on the remaining time is directly received from the numerical control device 20, or the remaining time may be recognized by holding the information on the dead time set in the numerical control device 20, and calculating (counting) the remaining time of the dead time after receiving the reception signal from the numerical control device 20.

According to the machine tool 1 of the present example having the above configuration, the operator mounts the tool T to the spindle 7 or removes the tool T from the spindle 7 as follows.

That is, first, the spindle head 6 is moved to a position below the Z-axis direction set as a tool attachment/detachment position under the control of the numerical control device 20 via an operation panel, not shown. In this case, the tool T is attached to the spindle 7, and the operator removes the current tool T from the spindle 7 and then attaches a new tool T to the spindle 7.

Next, after the operator presses the removal button of the manual operation unit 18 with the tool T attached to the spindle 7 held by one hand, for example, when the weight of the tool T to be removed is heavy, the operator takes an appropriate posture such as holding the tool T with both hands.

When the operator presses the discharge button, a discharge signal is transmitted from the manual operation unit 18 to the numerical control device 20, and when the numerical control device 20 receives the discharge signal, the numerical control device transmits the reception signal to the notification control unit 23, counts the elapsed time from the reception time, and when the elapsed time reaches a preset hesitation time, transmits a drive signal (signal for supply) corresponding to the discharge signal to the switching valve 17, and supplies pressurized oil to the hydraulic cylinder 15. Thereby, the pull rod 13 and the collet 11 move downward, the collet 11 opens, and the operator can pull out the tool T from the mounting hole 8.

On the other hand, the notification control unit 23 receives the reception signal from the numerical control device 20, turns on the lamp 22 alternately at preset time intervals, and then the notification control unit 23 recognizes the remaining time of the dead time, turns on and off the lamp 20 alternately so that the time intervals become shorter as the recognized remaining time becomes shorter, and turns off the lamp 22 after the dead time elapses. In this way, the operator can objectively predict or recognize the remaining time until the tool T is released from the holding by the holding mechanism 10 by recognizing the on/off alternation interval of the lamp 20, and can sufficiently make the posture for receiving the tool T when the tool T is disengaged from the spindle 7. Therefore, the operator can take the tool T off with ease even if the weight of the tool T is heavy.

Next, the operator presses the attachment button of the manual operation unit 18 in a state where a new tool T is inserted into the attachment hole 8 of the spindle 7. When the operator presses the installation button, an installation signal is transmitted from the manual operation unit 18 to the numerical control device 20, and when the installation signal is received, the numerical control device 20 transmits the reception signal to the notification control unit 23, counts the elapsed time from the reception time, and when the elapsed time reaches a preset hesitation time, transmits a drive signal (signal for stopping) corresponding to the installation signal to the switching valve 17, and stops the supply of the pressurized oil to the hydraulic cylinder 15. Thereby, the pull rod 13 and the collet 11 move upward, the collet 11 is closed, and the tool T is mounted in the mounting hole 8 of the spindle 7.

On the other hand, the notification control unit 23 receives the reception signal from the numerical control device 20, and then turns on the lamp 22 alternately at preset time intervals, and thereafter, the notification control unit 23 recognizes the remaining time of the dead time, turns on and off the lamp 20 alternately so that the time intervals become shorter as the recognized remaining time becomes shorter, but turns off the lamp 22 after the dead time elapses. Thus, the operator can objectively predict or recognize the remaining time until a new tool T is held by the holding mechanism 10 by recognizing the on/off alternation interval of the lamp 20. Therefore, when the operator mounts the tool T in the mounting hole 8 of the spindle 7, the operator can take a countermeasure such as pressing the tool T against the mounting hole 8 sufficient to mount the tool T to the spindle 7, and can mount the tool T to the spindle 7 with high accuracy even when the weight of the tool T is heavy.

Further, as described above, the operator can sufficiently perform the attaching and detaching operation when attaching and detaching the tool T to and from the spindle 7, but even in this case, there may be a case where the posture cannot be sufficiently made before the holding and releasing operation of the holding mechanism 10 is performed due to some factor, and in this case, the operator can press the cancel button of the manual operation section 18 before the dead time elapses and cancel the operation input before.

While an embodiment of the present invention has been described above, specific embodiments that can be adopted by the present invention are not limited to this embodiment at all.

For example, although a machining center has been exemplified as the machine tool 1 in the above example, the machine tool to which the present invention is applicable is not limited to this, and includes all conventionally known machine tools. In the above example, the spindle 7 is exemplified as the holding portion for holding the tool T, but the present invention is not limited thereto, and all holding portions for holding the tool T in the machine tool are included in the holding portion of the present invention.

In the above example, the notification control unit 23 is configured to alternately turn on and off the lamp 22 at time intervals that are shortened as the remaining time of the dead time is shortened, but the present invention is not limited to this, and the notification control unit 23 may be configured to turn on the lamp 22 all the time after receiving the reception signal, and to decrease or increase the light emission intensity of the lamp 22 as the remaining time is shortened. With such an embodiment, the operator can also objectively predict or recognize the remaining time until the holding mechanism 10 performs the action.

In the above example, the information on the remaining time of the dead time is reported using the lamp 22, but the present invention is not limited to this, and the report control unit 23 may be an embodiment as follows: the information on the remaining time is reported by controlling the on/off state (on/off alternation or light emission intensity) of a lamp provided for illuminating the machining area of the machine tool 1.

In the above example, the information on the remaining time is reported using one lamp 22, but the present invention is not limited to this, and instead of the lamp 22, a plurality of (5 in this example) lamps 24 to 28 as shown in fig. 3 may be provided in the spindle head 6. In this case, the notification control unit 23 may employ the following embodiment: the information corresponding to the remaining time is reported by selectively lighting preset lamps 24-29 according to the remaining time. For example, as the remaining time becomes shorter, an example in which the lamps are sequentially turned on from the uppermost lamp 24 to the lower side, and conversely, an example in which the lamps are sequentially turned on from the lowermost lamp 28 to the upper side may be illustrated. In this case, the light emission colors of the lamps 24 to 28 may be different from each other. With such an embodiment, the operator can also objectively predict or recognize the remaining time until the holding mechanism 10 performs the action.

In addition, instead of the lamp 22 of the above example, the speaker 29 shown in fig. 4 may be disposed near the position where the operator performs the attaching and detaching operation of the tool T. In this case, the notification control unit 23 may employ the following embodiment: the information corresponding to the remaining time is notified by the sound output from the speaker 29, and for example, the sound is intermittently output from the speaker 29, and the output interval of the sound is shortened as the remaining time becomes shorter. Alternatively, the notification control unit 23 may employ the following embodiments: the speaker 29 is configured to output a voice, and the remaining time is notified by counting down the voice. With these embodiments, the operator can also objectively predict or recognize the remaining time until the holding mechanism performs the action.

In short, the lamp 22 may be an energy output device capable of outputting energy that can be sensed by a human to the outside and changing the output state of the energy, and the notification control unit 23 may employ an embodiment in which the output state of the energy output by the energy output device is changed according to the remaining time.

The description of the embodiments is repeated in all respects to be illustrative and not restrictive. Those skilled in the art can make modifications and changes as appropriate. The scope of the invention is indicated by the claims rather than the embodiments described. Further, the scope of the present invention includes modifications of the embodiments within the range equivalent to the claims.

Description of the symbols

1 machine tool

6 spindle head

7 Main shaft

8 mounting hole

10 holding mechanism

11 collet chuck

12 outer cylinder member

13 draw bar

14 coil spring

15 oil hydraulic cylinder

16 pressure oil supply source

17 switching valve

18 manual operation part

20 numerical control device

21 hesitation state notification unit

22 Lamp

23 report control part

24-28 lamp

29 speaker