Machine tool

Abstract

To provide a machine tool capable of avoiding abnormal vibration and positioning failure even if a fluid compressor connected to a motion mechanism part is provided, and easily applicable to a relatively wide motion mechanism part.SOLUTION: The machining center M includes a ram 5, a fluid compressor 16, a power transmission unit 14 and a pressure accumulation switching device 15 capable of switching connection / disconnection between the ram 5 and the fluid compressor 16, and a control device 20 that controls the switching operation of the power transmission unit 14 and the pressure accumulation switching device 15, and the control device 20 includes a position information acquisition unit 22 that acquires position information of the ram 5, and an accumulation possibility determination unit 28 that determines whether or not there is a possibility that the cutting tool 2 comes into contact with the workpiece 1 within a predetermined machining range based on the acquired position information. When the pressure accumulation possibility determination unit 28 determines that there is no possibility that the cutting tool 2 comes into contact with the work material 1, the ram 5 is connected to the fluid compressor 16 by the power transmission unit 14 and the pressure accumulation switching device 15.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a machine tool having a fluid compressor connectable to a motion mechanism. [Background technology]

[0002] A machine tool is a machine that converts electrical energy into power using a motor to drive a tool and / or a workpiece, and performs processing by imparting relative motion between the tool and the workpiece. However, the energy converted into power by the motor is generally used for other movements besides machining, such as changing multiple tools and positioning to the next machining position, and various measures have been proposed to make effective use of energy for movements other than machining. For example, JP 2020-529321 A (Patent Document 1) discloses an invention in which a press punch of a machine tool, which is a press device, is mechanically coupled to a pump element, and compressed air can be supplied to a pneumatic energy storage unit (storage tank) by driving the pump element in synchronization with the reciprocating motion of the press punch. According to this invention, by using compressed air as the operating source for the ejector mandrel, a separate compressed air supply is no longer necessary. Furthermore, Japanese Patent Application Laid-Open Publication No. 2015-188896 (Patent Document 2) discloses an invention in which, in a press device in which a movable die arranged opposite a fixed die clamps and forms a workpiece, the movable die is connected to a compressor, and the compressor operates to compress when the movable die moves from the top dead center to the bottom dead center, and the generated compressed air is used as compressed air for machine tools and in factories. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2020-529321 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-188896 Summary of the Invention [Problem to be solved by the invention]

[0004] In the invention of Patent Document 1, the pump element is mechanically connected to the press punch, which is a motion mechanism, so compressed air can be generated efficiently, but there is a problem that electrical energy is constantly consumed to generate compressed air. Also, since the driving load of the pump element changes due to pressure fluctuations in the storage tank, in the case of machine tools that are precisely controlled by servos, there is a risk of abnormal vibrations and positioning errors, and the installation location is limited depending on the selection of the pump element, such as the inability to connect to high-speed operating parts. The invention of Patent Document 2 does not waste energy when used with a machine tool that repeatedly operates on an axis in the direction of gravity, such as a press machine. However, there are restrictions on operation, which causes the problem that the motion mechanism to which the fluid compressor can be connected is limited.

[0005] Therefore, the present disclosure aims to provide a machine tool that is equipped with a fluid compressor that can be connected to a motion mechanism, but that can avoid abnormal vibrations and positioning errors, save electrical energy, and is easy to adopt for a relatively wide range of motion mechanisms. [Means for solving the problem]

[0006] In order to achieve the above object, a first configuration of the present disclosure includes a motion mechanism unit to which a tool is attached and which can move in a predetermined direction; a fluid compressor; a switching means provided between the motion mechanism and the fluid compressor, capable of switching between connection and disconnection of the motion mechanism and the fluid compressor, and a control device for controlling the switching operation of the switching means, wherein, in a state in which the motion mechanism and the fluid compressor are connected by the switching means, the fluid compressor performs a pressure accumulation operation in accordance with movement of the motion mechanism, The control device a position information acquisition unit that acquires position information of the motion mechanism unit; a pressure accumulation possibility determination unit that determines whether or not there is a possibility that the tool will come into contact with a workpiece within a predetermined processing range based on the acquired position information, When the pressure accumulation possibility determining unit determines that there is no possibility that the tool will come into contact with the workpiece, the switching means connects the motion mechanism unit to the fluid compressor. In order to achieve the above object, a second configuration of the present disclosure includes a motion mechanism unit to which a tool is attached and which can move in a predetermined direction; a fluid compressor; a switching means provided between the motion mechanism and the fluid compressor, capable of switching between connection and disconnection of the motion mechanism and the fluid compressor, and a control device for controlling the switching operation of the switching means, wherein, in a state in which the motion mechanism and the fluid compressor are connected by the switching means, the fluid compressor performs a pressure accumulation operation in accordance with movement of the motion mechanism, The control device a program information acquisition unit that acquires program information for controlling the motion mechanism unit; a pressure accumulation possibility determination unit that determines whether or not machining is being performed by the tool based on the program information acquired by the program information acquisition unit, When the pressure accumulation possibility determining unit determines that no processing has been performed, the switching means connects the motion mechanism unit to the fluid compressor. In order to achieve the above object, a third configuration of the present disclosure includes a motion mechanism unit to which a tool is attached and which can move in a predetermined direction; a fluid compressor; a switching means provided between the motion mechanism and the fluid compressor, capable of switching between connection and disconnection of the motion mechanism and the fluid compressor, and a control device for controlling the switching operation of the switching means, wherein, in a state in which the motion mechanism and the fluid compressor are connected by the switching means, the fluid compressor performs a pressure accumulation operation in accordance with movement of the motion mechanism, The control device a tolerance information acquisition unit that acquires tolerance information, which is predetermined allowable information related to control of the motion mechanism unit; a pressure accumulation possibility determination unit that determines whether the tolerance information acquired by the tolerance information acquisition unit exceeds a preset tolerance threshold value, When the pressure accumulation possibility determining unit determines that the tolerance information exceeds the tolerance threshold, the switching means connects the motion mechanism unit to the fluid compressor. Another aspect of the present disclosure is a compressor, comprising: a pressure accumulator that stores the fluid compressed by the fluid compressor; a pressure measuring means for measuring the pressure of the compressed fluid in the pressure accumulator, The control device determines whether the pressure measured by the pressure measuring means is within a predetermined range, and if the measured pressure is not within the predetermined range, the control device does not make a determination using the pressure accumulation possibility determination unit, and disconnects the movement mechanism unit from the fluid compressor using the switching means. [Effects of the Invention]

[0007] According to the present disclosure, pressure accumulation by the fluid compressor is performed at a timing that does not affect machining, thereby saving electrical energy consumed in generating compressed fluid, and even if a fluid compressor connected to a motion mechanism is provided, abnormal vibrations and positioning errors can be avoided. Furthermore, because the motion mechanism and fluid compressor are not constantly connected, there are fewer restrictions on installation location, making it easier to adopt to a relatively wide range of motion mechanisms. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a configuration of a machining center. [Figure 2] 4 is a flowchart of switching control of the pressure accumulation switching device. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 shows an outline of the configuration of a machining center M, which is an example of a machine tool according to the present disclosure. In the machining center M, a cutting tool 2 for machining a workpiece 1 is attached to a tool holder 3. The cutting tool 2 is an example of a tool of the present disclosure. The tool holder 3 is attached to the spindle 4 via a fitting portion. The spindle 4 is provided on a ram 5. The spindle 4 is movable in the vertical direction by a Z-axis motor 6 provided on the ram 5 and a Z-axis ball screw mechanism 7 connected to the Z-axis motor 6. The ram 5 is provided on a column 8. The ram 5 is connected to an X-axis motor 10 via an X-axis ball screw mechanism 9 provided on the column 8, and is movable in the X-axis direction. The ram 5 is an example of a motion mechanism portion of the present disclosure, and the X-axis direction is an example of a predetermined direction of the present disclosure.

[0010] A table 11 on which a workpiece 1 is placed can be moved in the Y-axis direction, which is perpendicular to the plane of the drawing, by a Y-axis ball screw mechanism (not shown). These screw mechanisms enable the cutting tool 2 to be positioned relative to any three-axis position of the X, Y, and Z axes of the workpiece 1. The X and Y-axis ball screw mechanisms further position the tool holder 3 in a tool changer 12 installed outside the machining area, and the tool holder 3 can be replaced via the tool changer 12 with another tool stored in a tool stocker 13.

[0011] In this machining center M, the ram 5 that moves in the X-axis direction is provided with a power transmission unit 14. The power transmission unit 14 is connected to a fluid compressor 16 via a pressure-accumulation switching device 15 that can be switched between connection and disconnection. The power transmission unit 14 and the pressure-accumulation switching device 15 are an example of the switching means of the present disclosure. The pressure accumulation switching device 15 may be one that switches the mechanical connection between the power transmission unit 14 and the plunger of the fluid compressor 16 by controlling a gear mechanism or the like with an actuator or the like. However, since the purpose of the pressure accumulation switching device 15 is to switch the load on the X-axis motor 10 that operates the ram 5, the structure is not limited, and it may be one that performs fluid control, such as a mechanism that switches the operating load of the fluid compressor 16 with a valve or the like, or a configuration that releases fluid to an open part other than the pressure accumulation tank 17. Fluid compressor 16 is a plunger pump that accumulates pressure when the plunger moves, for example, in the negative X-axis direction (left side in FIG. 1 ). Accumulation switching device 15 is connected to the plunger of fluid compressor 16. The discharge side of fluid compressor 16 is connected to accumulator tank 17. Accumulator tank 17 is capable of accumulating pressure of compressed fluid such as air or oil compressed by fluid compressor 16. Accumulator tank 17 is provided with pressure gauge 18. Accumulator tank 17 is an example of an accumulator unit of the present disclosure, and pressure gauge 18 is an example of a pressure measuring means of the present disclosure.

[0012] The control device 20 of the machining center M includes a CPU and a memory connected to the CPU. In addition to control sections for the X, Y, and Z axes, the control device 20 also includes, as functional sections for switching the operation of the pressure accumulation switching device 15, a current pressure acquisition section 21, an accumulated pressure limit storage section 22, a position information acquisition section 23, a workpiece information storage section 24, a program information acquisition section 25, a tolerance information acquisition section 26, a tolerance threshold storage section 27, an accumulation pressure possibility determination section 28, and an accumulated pressure switching section 29. The control device 20 executes switching control of the pressure accumulation switching device 15, which will be described later, in accordance with a program stored in a non-transitory computer-readable storage medium including a memory connected to the CPU. The current pressure acquisition unit 21 acquires the current pressure from the pressure gauge 18 of the pressure accumulator tank 17 . The pressure accumulation limit storage unit 22 stores the allowable value of the pressure accumulation in the pressure accumulator tank 17. The position information acquisition unit 23 acquires the current position of the ram 5 used for pressure accumulation. For example, the current position is acquired based on information from a position detector such as a position detection encoder of the X-axis motor 10 or a scale attached to the column 8. The workpiece information storage unit 24 stores information about the workpiece 1. The program information acquisition unit 25 acquires program command values ​​for controlling the RAM 5 from the memory of the control device 20 .

[0013] The tolerance information acquisition unit 26 acquires tolerance information relating to the operational settings of the RAM 5 from the memory of the control device 20 . The tolerance information is allowable information set for the quality of the workpiece 1 after machining, such as various allowable values ​​allowed in machining the workpiece 1. Examples of tolerance information include the allowable amount of machining error, the allowable operating error of position commands, the allowable range of vibration, and machining information by tool type. The quality after machining can be anything desired for the workpiece after machining, and can be any type, such as dimensional accuracy, surface roughness, geometric tolerance, or uniformity of residual stress. The tolerance threshold value storage unit 27 stores a tolerance threshold value, which is an upper limit value of tolerance information for determining whether or not the fluid compressor 16 is allowed to perform a pressure accumulation operation. The pressure accumulation possibility determination unit 28 determines whether or not pressure accumulation operation by the fluid compressor 16 is possible, and sends the result to the pressure accumulation switching unit 29. Whether or not pressure accumulation operation is possible is determined based on the result of comparing the current pressure of the pressure accumulator tank 17 with the allowable pressure accumulation value, the result of determining whether or not the current position of the ram 5 is within the machining range, the result of determining whether or not machining is in progress, and the result of comparing the tolerance information with the tolerance threshold value, as will be described later. The pressure-accumulation switching unit 29 performs the switching operation of the pressure-accumulation switching device 15 in response to the determination result of the pressure-accumulation possibility determination unit 28 .

[0014] In the machining center M configured as above, the switching control of the pressure-accumulation switching device 15 by the control device 20 will be described with reference to the flowchart of FIG. First, in step (hereinafter referred to as “S”)- 1 , the current pressure acquisition unit 21 acquires the current pressure from the pressure gauge 18 installed in the pressure accumulator tank 17 . Next, in S-2, the pressure accumulation possibility determination unit 28 compares the allowable value of the accumulated pressure stored in the accumulated pressure limit memory unit 22 with the current pressure. If the current pressure is equal to or greater than the allowable value, the subsequent steps are skipped, and in S-10, the pressure accumulation switching unit 29 places the accumulated pressure switching device 15 in the accumulated pressure release state, i.e., the state in which the connection between the accumulated pressure switching device 15 and the plunger of the fluid compressor 16 has been released, and the processing ends. The allowable value of the accumulated pressure is an example of a predetermined range of the measured pressure in the present disclosure.

[0015] If it is determined in step S-2 that the current pressure is below the allowable value, the current position of the ram 5 is acquired by the position information acquisition unit 23 in step S-3. Next, in S-4, the workpiece position stored in the workpiece information memory unit 24 is compared with the current position obtained in S-3, and the pressure accumulation possibility determination unit 28 determines whether the current position of the ram 5 is within the processing range, i.e., whether there is a possibility that the workpiece 1 and cutting tool 2 may come into contact at the current position of the ram 5. The purpose of this determination is to determine the possibility of contact between the workpiece 1 and the cutting tool 2 and to avoid load fluctuations during machining. Specifically, therefore, the presence or absence of contact may be determined by virtually moving model information of the workpiece 1 and the cutting tool 2 according to the position information. Furthermore, it may be possible to determine the absence of contact from Z-axis position information and tool length information of the cutting tool 2, or to determine that no contact has occurred in the Y direction as well as in the X direction.

[0016] If it is determined in S-4 that the current position of the ram 5 is not within the machining range, the subsequent steps are skipped, and in S-9, the pressure-accumulation switching unit 29 places the pressure-accumulation switching device 15 in the pressure-accumulation state, i.e., the pressure-accumulation switching device 15 and the plunger of the fluid compressor 16 are connected, and the process ends. If the determination in S-4 indicates that the current position of the ram 5 is within the machining range, then in S-5 the program information acquisition unit 25 acquires program information set in the memory of the control device 20, and in S-6 the pressure accumulation possibility determination unit 28 determines whether the current block of the program is a cutting command, i.e., whether machining is in progress. Even if it is determined in S-4 that the current position of the ram 5 is within the machining range, if the execution line of the program is a positioning command indicated by a G code such as G0, or an M code related to tool change or pallet change, there is no possibility of contact between the workpiece 1 and the cutting tool 2. Therefore, if the current block is not a cutting command, the subsequent steps are skipped, and in S-9 the pressure accumulation switching device 15 is set to the pressure accumulation state, ending the process. However, in S-6, instead of using the current operation, a method may be adopted in which the switching time of the pressure storage switching device 15 is taken into consideration, and by reading ahead the program command, it is determined whether or not machining is in progress when switching is completed.

[0017] If it is determined in S-6 that machining is in progress, the tolerance information acquisition unit 26 acquires tolerance information set in the memory of the control device 20 in S-7. Next, in S-8, the pressure accumulation possibility determination unit 28 determines whether the acquired current tolerance information exceeds the tolerance threshold stored in the tolerance threshold storage unit 27. If the tolerance information exceeds the tolerance threshold, it can be determined that the tolerance information has a margin of error and that accumulating pressure will not affect quality, and therefore, in S-9, the pressure accumulation switching device 15 is set to pressure accumulation operation, and the process ends. On the other hand, if the tolerance information is below the tolerance threshold, it can be determined that accumulating pressure may affect quality, and therefore, in S-10, the pressure accumulation switching device 15 is set to pressure accumulation release, and the process ends. For example, if the current operational allowable error, which is the tolerance information, is 0.01 mm while the tolerance threshold is 0.05 mm, the tolerance information is smaller, so the result is NO in S-8 and pressure accumulation is released in S-10.

[0018] In this way, the machining center M of the above embodiment includes the ram 5 that is equipped with the cutting tool 2 and is movable in the X-axis direction, the fluid compressor 16, the power transmission unit 14 and the pressure accumulation switching device 15 that are provided between the ram 5 and the fluid compressor 16 and are capable of switching between connection and disconnection between the ram 5 and the fluid compressor 16, and the control device 20 that controls the switching operation of the power transmission unit 14 and the pressure accumulation switching device 15, and when the ram 5 and the fluid compressor 16 are connected by the power transmission unit 14 and the pressure accumulation switching device 15, the fluid compressor 16 performs a pressure accumulation operation as the ram 5 moves.

[0019] The control device 20 has a position information acquisition unit 23 that acquires position information of the ram 5, and a pressure accumulation possibility determination unit 28 that determines whether or not there is a possibility that the cutting tool 2 will come into contact with the workpiece 1 within a predetermined processing range based on the acquired position information, When the pressure accumulation possibility determining unit 28 determines that there is no possibility that the cutting tool 2 will come into contact with the workpiece 1 , the power transmission unit 14 and the pressure accumulation switching device 15 connect the ram 5 to the fluid compressor 16 . The control device 20 also includes a program information acquisition unit 25 that acquires program information for controlling the ram 5, and a pressure accumulation possibility determination unit 28 that determines whether or not machining is being performed by the cutting tool 2 based on the program information acquired by the program information acquisition unit 25, If the pressure accumulation possibility determining unit 28 determines that no processing has been performed, the ram 5 is connected to the fluid compressor 16 by the power transmission unit 14 and the pressure accumulation switching device 15 . Furthermore, the control device 20 has a tolerance information acquisition unit 26 that acquires tolerance information, which is a predetermined allowable value related to the control of the ram 5, and a pressure accumulation possibility determination unit 28 that determines whether the tolerance information acquired by the tolerance information acquisition unit 26 exceeds a preset tolerance threshold value, If the pressure accumulation possibility determining unit 28 determines that the tolerance information exceeds the tolerance threshold, the power transmission unit 14 and the pressure accumulation switching device 15 connect the ram 5 to the fluid compressor 16 .

[0020] With these configurations, pressure is accumulated by the fluid compressor 16 at a time that does not affect machining, so it is possible to save on the electrical energy consumed in generating compressed air, and it is possible to avoid abnormal vibrations and positioning errors even when the fluid compressor 16 is connected to the ram 5. Furthermore, because the ram 5 and fluid compressor 16 are not constantly connected, there are fewer restrictions on the installation location, making it easier to adopt for a relatively wide range of motion mechanisms.

[0021] On the other hand, the machining center M further includes an accumulator tank 17 that stores the fluid compressed by the fluid compressor 16, and a pressure gauge 18 that measures the pressure of the compressed fluid in the accumulator tank 17. The control device 20 determines whether the current pressure measured by the pressure gauge 18 is within an allowable value, and if the current pressure is not within the allowable value, the pressure accumulation possibility determination unit 28 does not make a determination, and the power transmission unit 14 and the pressure accumulation switching device 15 disconnect the ram 5 from the fluid compressor 16. Therefore, excessive pressure accumulation operation can be avoided and the pressure accumulator tank 17 can be protected.

[0022] Modifications of the present disclosure will be described below. In the switching control of the pressure-accumulation switching device 15, modifications such as changing the order of steps or omitting some steps may be made without departing from the spirit of the invention. For example, in the flowchart of Fig. 2, the determination of the current pressure of the accumulator tank against the allowable value in S-2 may be performed after the determination of the tolerance information against the tolerance threshold in S-8. Also, one or more of the determination of the current pressure of the accumulator tank against the allowable value in S-2, the determination of whether the current position is within the machining range in S-4, the determination of whether machining is in progress in S-6, and the determination of the tolerance value against the tolerance threshold in S-8 may be omitted. Therefore, the control device can also omit one or more of the current pressure acquisition unit and accumulated pressure limit memory unit, the position information acquisition unit and workpiece information memory unit, the program information acquisition unit, the tolerance information acquisition unit and the tolerance threshold memory unit.

[0023] The content of the steps is not limited to the above. For example, as an alternative to determining the possibility of contact between the workpiece 1 and the cutting tool 2 in step S-4, as shown in Figure 1, a detection target 50 may be provided on the ram 5, and a signal from a proximity sensor 51 provided on the column 8 may be monitored to directly detect that the cutting tool 2 is not above the table 11. It is also possible to add additional steps. For example, as a condition for determining whether to store pressure or release pressure, a step may be added in which, before the storage operation in S-9, the speed is calculated from the amount of change in the current position per unit time, and whether or not the speed is within the allowable value of the fluid compressor 16 is determined, in order to prevent damage to the pump or link mechanism of the fluid compressor 16. In this case, if the speed is not within the allowable value, the storage switching device 15 is switched to release pressure (S-10). Furthermore, for example, when a tool other than a finishing tool, such as an insert-type end mill, is selected, or when the machining direction of a tool such as a drill or tap is different from the axis used for pressure accumulation, there is no effect of the pressure accumulation operation, so these cases may be used as the judgment condition.In addition, it may be possible to determine whether the currently selected process is a rough process or a finish process based on information such as CAM (Computer Aided Manufacturing) used to generate the program used for machining, not limited to the control device, and add a judgment condition to accumulate pressure in the rough process.

[0024] In the above embodiment, a plunger pump that accumulates pressure when the plunger moves in the negative X-axis direction is described as an example of the fluid compressor, but a reciprocating pump with a different volume change mechanism, such as a vane pump or diaphragm pump, may also be used. Furthermore, the fluid compressor may be a reciprocating pump that can obtain output regardless of the operating direction of the piston, a system that adds a mechanism that converts rotary motion into reciprocating motion using a link mechanism, or a rotary pump or non-positive displacement pump that compresses fluid directly using rotary motion, and the form is not limited. Furthermore, although a machining center has been used as an example, the type of machine tool is not limited, and any type of machine can be used as long as it performs processing by imparting relative motion between a tool and a workpiece, such as a lathe, a cutting machine such as a multi-tasking machine, a forging machine, a molding machine, etc. Therefore, the motion mechanism is not limited to a ram as long as it is connected to a fluid compressor and can move in a predetermined direction. [Explanation of symbols]

[0025] 1··Workpiece, 2··Cutting tool, 3··Tool holder, 4··Spindle, 5··Ram, 6··Z-axis motor, 7··Z-axis ball screw mechanism, 8··Column, 9··X-axis ball screw mechanism, 10··X-axis motor, 11··Table, 12··Tool changer, 13··Tool stocker, 14··Power transmission unit, 15··Accumulated pressure switching device, 16··Fluid compressor, 17··Accumulated pressure tank, 1 8··Pressure gauge, 20··Control device, 21··Current pressure acquisition unit, 22··Accumulated pressure limit memory unit, 23··Position information acquisition unit, 24··Workpiece information memory unit, 25··Program information acquisition unit, 26··Tolerance information acquisition unit, 27··Tolerance threshold memory unit, 28··Accumulated pressure possibility determination unit, 29··Accumulated pressure switching unit, 50··Detected unit, 51··Proximity sensor, M··Machining center.

Claims

1. a motion mechanism unit to which a tool is attached and which can move in a predetermined direction; a fluid compressor; a switching means provided between the motion mechanism and the fluid compressor, capable of switching between connection and disconnection of the motion mechanism and the fluid compressor, and a control device for controlling the switching operation of the switching means, wherein, in a state in which the motion mechanism and the fluid compressor are connected by the switching means, the fluid compressor performs a pressure accumulation operation in accordance with movement of the motion mechanism, The control device a position information acquisition unit that acquires position information of the motion mechanism unit; a pressure accumulation possibility determination unit that determines whether or not there is a possibility that the tool will come into contact with a workpiece within a predetermined processing range based on the acquired position information, When the pressure accumulation possibility determination unit determines that there is no possibility that the tool will come into contact with the workpiece, the machine tool connects the motion mechanism unit to the fluid compressor using the switching means.

2. a motion mechanism unit to which a tool is attached and which can move in a predetermined direction; a fluid compressor; a switching means provided between the motion mechanism and the fluid compressor, capable of switching between connection and disconnection of the motion mechanism and the fluid compressor, and a control device for controlling the switching operation of the switching means, wherein, in a state in which the motion mechanism and the fluid compressor are connected by the switching means, the fluid compressor performs a pressure accumulation operation in accordance with movement of the motion mechanism, The control device a program information acquisition unit that acquires program information for controlling the motion mechanism unit; a pressure accumulation possibility determination unit that determines whether or not machining is being performed by the tool based on the program information acquired by the program information acquisition unit, When the pressure accumulation possibility determination unit determines that no machining is being performed, the machine tool connects the motion mechanism unit to the fluid compressor by the switching means.

3. a motion mechanism unit to which a tool is attached and which can move in a predetermined direction; a fluid compressor; a switching means provided between the motion mechanism and the fluid compressor, capable of switching between connection and disconnection of the motion mechanism and the fluid compressor, and a control device for controlling the switching operation of the switching means, wherein, in a state in which the motion mechanism and the fluid compressor are connected by the switching means, the fluid compressor performs a pressure accumulation operation in accordance with movement of the motion mechanism, The control device a tolerance information acquisition unit that acquires tolerance information, which is predetermined allowable information related to control of the motion mechanism unit; a pressure accumulation possibility determination unit that determines whether the tolerance information acquired by the tolerance information acquisition unit exceeds a preset tolerance threshold value, When the pressure accumulation possibility determination unit determines that the tolerance information exceeds the tolerance threshold value, the machine tool connects the motion mechanism unit to the fluid compressor by the switching means.

4. a pressure accumulator that stores the fluid compressed by the fluid compressor; a pressure measuring means for measuring the pressure of the compressed fluid in the pressure accumulator, 4. The machine tool according to claim 1, wherein the control device determines whether the pressure measured by the pressure measuring means is within a predetermined range, and if the measured pressure is not within the predetermined range, the control device does not make a determination by the pressure accumulation possibility determining unit, and causes the switching means to disconnect the motion mechanism unit from the fluid compressor.

Images