JP2017191359A - Machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machine tool capable of improving waste of electric power of a servomotor, for a feeder in which a table to be fed is in a stopped condition.SOLUTION: The machine tool comprises: multiple feeders 40, 50, 60 having feed screws, servo motors 41, 51, 61, and brakes 44, 54, 64; a numerical controller 11 for generating control signals, and supplying electric currents corresponding to the control signals, to the servo motors 41, 51, 61; and a brake controller 25. The brake controller 25 receives the control signals from the numerical controller 11, and for the feeders 40, 50, 60 having received the control signals, during a period when receiving the control signals, the brake controller allows supply of currents to the servo motors 41, 51, 61 respectively from the numerical controller 11 and releases the brakes 44, 54, 64 respectively and on the other hand, for the feeders 40, 50, 60 having not received the control signals, during a period when not receiving the control signals, the brake controller shuts off the currents to be supplied to the servo motors 41, 51, 61 respectively from the numerical controller 11, makes the brakes 44, 54, 64 be actuated respectively and stops rotations of the feed screws.SELECTED DRAWING: Figure 1

Description

  The present invention generates a feed screw, a servo motor that drives the feed screw, and a plurality of feed devices each including a brake that stops rotation of the feed screw or the servo motor, and a control signal related to each feed device, The present invention relates to a machine tool including a numerical control unit that supplies a current according to the control signal to a corresponding servo motor and numerically controls its operation.

  As one of machine tools having the above configuration, a machine tool disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-47342 (the following Patent Document 1) is known. The machine tool includes a feed mechanism that moves the feed base in a feed direction including at least a vertical feed component, and a control unit that controls the operation of the feed mechanism. The feed mechanism is attached to the feed base. A feed screw that engages and moves the feed base in the feed direction, and a servo motor that is connected to the feed screw via a power transmission mechanism and rotates the feed screw about its axis.

  Further, the machine tool monitors the drive current value output from the control means to the servo motor, and the torque acting on the output shaft of the servo motor when the drive current value is out of a predetermined reference range. The abnormality detecting means for determining that the abnormality is abnormal, the braking mechanism that is directly connected to the feed screw and stops the rotation of the feed screw, and the torque that acts on the output shaft of the servo motor becomes abnormal. And a braking drive unit that receives a detection signal output from the detection unit and drives the braking mechanism to stop the rotation of the feed screw.

  Thus, in this machine tool, normally, when the main power of the control panel is turned on, current is supplied to the servo motor, position control by the servo motor is executed, and the braking mechanism is in a non-braking state. The rotation of the feed screw is allowed. On the other hand, when the main power supply is cut off, the supply of current to the servo motor is cut off, the position control by the servo motor is stopped, the braking mechanism enters the braking state, and the feed screw rotates. Stop.

  In this machine tool, in the operating state where the main power supply is turned on, the drive current value supplied from the control means to the servomotor is monitored by the abnormality detection means, and the drive current value is preset. When out of the reference range, the abnormality detecting means causes an abnormal torque acting on the output shaft of the servo motor, that is, the power transmission mechanism is abnormal or the chain connecting the balance weight is cut. It is determined that

  When an abnormality is detected by the abnormality detection means, the braking mechanism is driven by the braking drive means, and the rotation of the feed screw is stopped by the braking mechanism, and thus the rotation of the feed screw is stopped. As a result, it is possible to prevent the feed base from moving downward due to its own weight.

JP 2001-47342 A

  As described above, the conventional machine tool is in a state where the current is always supplied from the control means to the servomotor in the operating state where the main power is turned on, and the servomotor is always performing the position control. Even in such a state where the main power is turned on, the feeding mechanism is often in a state where the feeding base is not moved.

  For example, when the main power supply is turned on but the operator is setting up the machine tool and no machining is being performed, each feed mechanism is in a stopped state that hardly moves its feed base. is there. Even during automatic operation using the NC program, while the feed mechanism of a certain feed axis moves the feed base, the feed mechanism related to another feed shaft stops the feed base. In some cases.

  However, conventionally, current is always supplied to the servo motor of the feed mechanism in a state where the feed base is stopped, so that unnecessary power is wasted. In the field of the machine tool, reduction of all costs is always required, and it is a matter of course that improvement of such waste of electric power is also required.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a machine tool capable of improving the waste of electric power of a servo motor of a feed mechanism in which a platform is stopped. .

In order to solve the above problems, the present invention provides a feed screw, a servo motor that drives the feed screw, a plurality of feed devices each including a brake that stops rotation of the feed screw or the servo motor, and each feed device. A machine tool including a numerical control unit that generates a control signal and supplies a current according to the control signal to the corresponding servo motor to numerically control its operation,
The control signal related to each of the feeding devices generated by the numerical control unit is sequentially received from the numerical control unit,
For the feeding device that has received the control signal, while the control signal is being received, supply of current from the numerical control unit to the servo motor of the feeding device is permitted, and the brake of the feeding device is released. ,
For the feeding device that does not receive the control signal, while not receiving the control signal related to the feeding device, the current supplied from the numerical control unit to the servo motor of the feeding device is cut off, and the feeding device The present invention relates to a machine tool including a braking control unit configured to operate a brake to stop rotation of a servo motor or a feed screw.

  According to this machine tool, the brake control unit sequentially receives the control signals related to the feeding devices generated by the numerical control unit. The braking control unit allows the feeding device that has received the control signal to allow current to be supplied from the numerical control unit to the servo motor of the feeding device while receiving the control signal. The brake is released so that the position control by the feeding device is executed.

  On the other hand, for a feeding device that does not receive a control signal, the braking control unit cuts off the current supplied from the numerical control unit to the servo motor of the feeding device while the control signal related to the feeding device is not received. At the same time, the brake of the feed device is operated to stop the rotation of the servo motor or the feed screw. Since the servo motor and the feed screw are connected, the brake can stop the rotation of both the servo motor and the feed screw by directly stopping the rotation of the servo motor or the feed screw.

  As described above, according to this machine tool, for the feeding device in which the control signal is not generated by the numerical control unit, that is, the feeding device in the state where the feeding operation is stopped, the power supply to the servo motor is cut off. Since the position control is stopped and the feed screw is stopped by the brake, waste of electric power in the servo motor can be prevented and energy saving can be achieved.

  In addition, since the to-be-feeded base (for example, a carriage, a tool post, etc.) to which the feed device moves generally has a considerable weight, position control is performed to stop the to-be-feeded base at a predetermined position. In this case, the electric power supplied to the servo motor is considerably large. On the other hand, in a normal operating state, the power supplied to the brake to release the brake when moving the platform is much higher than the power supplied to the servo motor to stop the platform. Small. Therefore, even when a brake is newly provided in a feeder that is not provided with the brake, it is possible to save energy by cutting off the supply of power to the servo motor in a stopped state.

In the present invention, the machine tool has the same feed screw as the first feed shaft, the feed screw being disposed along the first feed shaft, and the moving body moving along the first feed shaft. In the plane, the feed screw is disposed along a second feed shaft that intersects the first feed shaft in a non-orthogonal state, and moves the first feed device along the second feed shaft. Comprising at least a device,
The numerical control unit operates the first feeding device and the second feeding device at the same time so as to move the moving body along a virtual feeding axis orthogonal to the first feeding axis or the second feeding axis. It may be configured.

  The first feeding device and the second feeding device in this machine tool are operated in synchronism while appropriately controlling them, so that the first feeding shaft or the virtual feeding shaft orthogonal to the second feeding shaft is operated. The moving body can be moved. Such a configuration is generally adopted in a compound lathe. According to this compound lathe, for example, turning without using the virtual feed axis and milling using the virtual feed axis are performed. It can be carried out.

  However, in this complex lathe, when machining without using a virtual feed axis, the feed device that only contributes to the creation of this virtual feed axis is in a stopped state during this period, and the supplied power is wasted. is there. In addition, some workpieces are only turned and do not require milling, and when machining such workpieces, the feeding device that contributes only to the creation of a virtual feed axis is It just wastes power.

  As described above, in the case of a machine tool configured to create a virtual feed axis by two feed devices (first feed device and second feed device), when machining without using the virtual feed axis, the virtual The feeding device that contributes only to the creation of the feed shaft consumes a large amount of power compared to other feeding devices. Therefore, in the case of such a machine tool, by cutting off the power supplied to the feeding device that has stopped the feeding operation, it is possible to achieve a greater energy reduction and obtain a greater energy saving effect. it can.

  Further, it is preferable that one of the first feeding device and the second feeding device has the feed screw disposed horizontally. Since the gravity of the platform (such as the moving body) does not act on the feed screw arranged horizontally, the feed screw is inclined and arranged on the feed screw in the axial direction. Compared with the case where the gravity of the to-be-supplied base acts, the brake needs to have a small braking force. Therefore, the power required for releasing the brake becomes small, and the energy consumed when releasing the brake can be reduced.

  As the brake, various types of brakes such as a hydraulic brake can be adopted in which power is obtained and the brake is brought into a non-braking state and the power is turned off, and the braking operation is controlled by electromagnetic force. An electromagnetic brake that enters a non-braking state when a current is supplied and enters a braking state when the current is interrupted can be preferably used.

  As described above, according to the machine tool according to the present invention, for a feeding device in which a control signal is not generated by the numerical control unit, that is, a feeding device in a state where the feeding operation is stopped, supply of power to the servo motor is performed. Since the position control is stopped and the feed screw is stopped by the brake, waste of electric power in the servo motor can be prevented and energy saving can be achieved.

  In particular, in the case of a machine tool configured to create a virtual feed axis by two feed devices (a first feed device and a second feed device), when machining without using the virtual feed axis, the virtual feed axis is used. A feeder that only contributes to the creation of the shaft wastes more power than other feeders. Therefore, in the case of such a machine tool, by cutting off the power supplied to the feeding device that has stopped the feeding operation, it is possible to achieve a greater energy reduction and obtain a greater energy saving effect. it can.

It is the block diagram which showed the numerical control part, braking control part, etc. of the machine tool which concern on one Embodiment of this invention. It is the side view which showed the motion mechanism part of the machine tool which concerns on this embodiment in the partial cross section. FIG. 3 is an enlarged view showing a part of a section where a servo motor of the Y′-axis feeding device shown in FIG. 2 is provided.

  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 this example includes a motion mechanism unit 30 and a control device 10. As shown in FIG. 2, the motion mechanism unit 30 includes a bed 31, a spindle base 32 that is disposed on the bed 31 and rotatably supports a spindle 33, and a carriage 34 that is also disposed on the bed 31. A saddle 35 is provided on the carriage 34 so as to be movable in the direction of the arrow Y ', and a tool post 36 is provided on the saddle 35 so as to be movable in the direction of the arrow X-axis. ing.

  The carriage 34 is driven by a Z-axis feeding device 60 and moves along a Z-axis direction that is a feed axis in a direction parallel to the axis of the main shaft 33 and perpendicular to the paper surface. Further, the saddle 35 is driven by the Y′-axis feeding device 50 and moves along the Y′-axis direction which is a feeding axis in a direction orthogonal to the Z-axis.

  Further, the tool post 36 holds the turret 37 so as to be rotatable about an axis parallel to the axis of the main shaft 33, is driven by an X-axis feeding device 40, is orthogonal to the Z-axis, and It moves along the X-axis direction which is a feed axis in a direction intersecting with the Y ′ axis in a non-orthogonal state. The X axis and the Y ′ axis are in the same plane.

  The Z-axis feeding device 60 is disposed on the bed 31 and guides the movement of the carriage 34 along the Z-axis direction, and the Z-axis servo is also disposed on the bed 31. A motor 61, a Z-axis ball screw (not shown) disposed along the Z-axis and connected to the Z-axis servomotor 61, and screwed into the Z-axis ball screw (not shown); A ball nut (not shown) fixed to the carriage 34 is used.

  Further, the Y′-axis feeding device 50 is reciprocated in the same manner as a Y′-axis guide portion (not shown) disposed on the carriage 34 and guiding the movement of the saddle 35 along the Y′-axis direction. A Y′-axis servomotor 51 disposed on the table 34, disposed along the Y′-axis, connected to the Y′-axis servomotor 51, and rotatably supported by bearings 57 and 58. A Y′-axis ball screw 52 and a ball nut 53 screwed into the Y′-axis ball screw 52 and fixed to the saddle 35 are included.

  Similarly, the X-axis feeding device 40 is disposed on the saddle 35 and is disposed on the saddle 35 and an X-axis guide portion (not shown) that guides the movement of the tool post 36 along the X-axis direction. An X-axis servomotor 41 provided, an X-axis ball screw 42 disposed along the X-axis, connected to the X-axis servomotor 41, and rotatably supported by bearings 47 and 48; The ball nut 43 is engaged with the X-axis ball screw 42 and fixed to the tool post 36.

  As shown in FIG. 3, the output shaft of the Y′-axis servo motor 51 of the Y′-axis feeding device 50 is connected to the end of the Y′-axis ball screw 52 via the coupling 55. . The Y′-axis ball screw 52 is fixedly provided with one member 54 a of the Y′-axis brake 54 constituted by an electromagnetic brake, and the other member 54 b of the Y′-axis brake 54 is fixedly provided on the housing 56. ing. Thus, when electric power is supplied to the Y′-axis brake 54 and the braking action is released, the Y′-axis servo motor 51 and the Y′-axis ball screw 52 become rotatable, and the Y′-axis brake 54 When the supply of electric power to is interrupted and a braking action is exerted, the rotation of the Y′-axis servo motor 51 and the Y′-axis ball screw 52 is stopped by this braking action.

  The X-axis feeding device 40 also has the same configuration as the Y′-axis feeding device 50, and as shown in FIG. 1, the X-axis feeding device 40 includes an X-axis brake 44 that is configured by an electromagnetic brake. When the electric power is supplied to the X-axis brake 44 and the braking action is released, the X-axis servo motor 41 and the X-axis ball screw 42 become rotatable, and the supply of electric power to the X-axis brake 44 is cut off. When the braking action is manifested, the rotation of the X-axis servo motor 41 and the X-axis ball screw 42 is stopped by this braking action.

  The Z-axis feeding device 60 has the same configuration as that of the Y′-axis feeding device 50. As shown in FIG. 1, the Z-axis feeding device 60 is a Z-axis brake 64 composed of an electromagnetic brake. When the electric power is supplied to the Z-axis brake 64 and the braking action is released, the Z-axis servo motor 61 and the Z-axis ball screw (not shown) become rotatable, and the Z-axis brake 64 When the supply of electric power is interrupted and the braking action is developed, the braking action stops the rotation of the Z-axis servomotor 61 and the Z-axis ball screw (not shown).

  Although not particularly illustrated, the output shaft of the X-axis servo motor 41 of the X-axis feed device 40 is connected to the end of the X-axis ball screw 42 via a coupling, and the Z-axis feed device 60 The output shaft of the Z-axis servo motor 61 is coupled to the end of a Z-axis ball screw (not shown) via a coupling.

  As shown in FIG. 1, the control device 10 includes a numerical control unit 11 and a braking control unit 25. The numerical control unit 11 includes a program storage unit 12, a program analysis unit 13, a position command unit 14, an X-axis control unit 15, a Y′-axis control unit 16, a Z-axis control unit 17, an X-axis servo amplifier 18, and Y ′. An axis servo amplifier 19 and a Z-axis servo amplifier 20 are provided. FIG. 1 shows only the main configuration of the numerical controller 11 for controlling the X-axis servomotor 41, the Y′-axis servomotor 51, the Z-axis servomotor 61, and the like.

  The program storage unit 12 is a functional unit that stores an NC program, and the NC program is input from the outside, for example. The program analysis unit 13 is a functional unit that reads and executes the NC program stored in the program storage unit 12, analyzes the read NC program, and generates an X axis, a generating Y axis, and a feed axis. A process of recognizing the movement position and the feed speed with respect to the Z axis and transmitting the recognized information to the position command unit 14 is performed. The generating Y-axis is a feeding axis created by a synchronized feeding operation of the X-axis feeding device 40 and the Y′-axis feeding device 50, and is a feeding axis orthogonal to the X-axis and the Z-axis.

  The position command unit 14 generates a position command (control signal) for each feed axis based on the movement position and feed speed for each feed axis received from the program analysis unit 13, and outputs the generated position command. The data are transmitted to the X-axis control unit 15, the Y′-axis control unit 16, and the Z-axis control unit 17, respectively.

  For example, when the position command unit 14 receives a command related to a movement position and a feed speed relating to the X axis, the position command unit 14 generates an X axis position command corresponding to the command and transmits it to the X axis control unit 15, and also relates to the Z axis. When a command related to the movement position and feed speed is received, a Z-axis position command corresponding to the command is generated and transmitted to the Z-axis control unit 17. Further, when the position command unit 14 receives a command related to the movement position and feed speed relating to the creation Y axis, the creation Y axis is created by a synchronized feed operation of the X axis feed device 40 and the Y ′ axis feed device 50. Therefore, the X-axis position command and the Y′-axis position command corresponding to the reception command are generated, the X-axis position command is transmitted to the X-axis control unit 15, and the Y′-axis position command is transmitted. Is transmitted to the Y′-axis control unit 16.

  Then, the X-axis control unit 15 that has received the position command generates a control signal corresponding to the received position command and transmits it to the X-axis servo amplifier 18, and the X-axis servo amplifier 18 responds to the received control signal. A drive current is supplied to the X-axis servo motor 41.

  Similarly, the Y′-axis control unit 16 generates a control signal corresponding to the received position command and transmits it to the Y′-axis servo amplifier 19, and the Y′-axis servo amplifier 19 drives according to the received control signal. A current is supplied to the Y′-axis servo motor 51.

  The Z-axis control unit 17 generates a control signal corresponding to the received position command and transmits the control signal to the Z-axis servo amplifier 20, and the Z-axis servo amplifier 20 supplies a drive current corresponding to the received control signal to the Z-axis. The servo motor 61 is supplied.

  Although not specifically shown in FIG. 1, the numerical control unit 11 controls a spindle motor (not shown) that rotates the spindle 33, and an indexing motor (not shown) that indexes the turret 37. And a drive motor for rotating the rotary tool T held by the turret 37 is controlled.

  Thus, the X-axis servo motor 41 is driven by the drive current supplied from the X-axis servo amplifier 18, and the Y′-axis servo motor 51 is driven by the drive current supplied from the Y′-axis servo amplifier 19. The Z-axis servo motor 61 is driven by the drive current supplied from the Z-axis servo amplifier 20.

  The motion mechanism unit 30 is controlled by the numerical control unit 11 with respect to the X-axis feeding device 40, the Y′-axis feeding device 50, and the Z-axis feeding device 60, and under the control of the numerical control unit 11, The turret 37 is moved in the Z-axis direction by the Z-axis feeding device 60, and is moved in the X-axis direction by the X-axis feeding device 40.

  The turret 37 is orthogonal to both the Z-axis and the X-axis by simultaneously driving the X-axis feeding device 40 and the Y′-axis feeding device 50 under the control of the numerical control unit 11. Move along the direction of the generating Y-axis. Specifically, the tool post 36 is moved in the X-axis minus direction by the X-axis feeding device 40, and simultaneously, in synchronization with this, the saddle 35 is moved in the Y'-axis plus direction by the Y'-axis feeding device 50. The turret 37 moves in the Y axis minus direction. On the contrary, the tool post 36 is moved in the X-axis plus direction by the X-axis feeding device 40, and at the same time, the saddle 35 is moved in the Y'-axis minus direction by the Y'-axis feeding device 50 in synchronization with this. Thus, the turret 37 moves in the Y axis plus direction.

  Thus, according to this machine tool 1, the tool T is held in a state where the work is held on the spindle 33, the tool T is held on the turret 37, and the work is rotated at a rotational speed for turning. The workpiece can be turned by moving in the XZ plane. Further, in a state where the rotation tool T held by the turret 37 is rotated while the rotation of the workpiece is stopped or the workpiece is slowly rotated, the rotation tool T is three-dimensionally composed of the X axis, the generating Y axis, and the Z axis. By moving in the space, so-called milling can be performed.

  The brake control unit 25 sequentially receives position commands (control signals) generated by the position command unit 14 and transmitted to the X-axis control unit 15, the Y′-axis control unit 16, and the Z-axis control unit 17, respectively. For the feeding device that has received the control signal, while the control signal is being received, supply of current from the numerical control unit 11 to the servo motor of the feeding device is permitted, and the brake of the feeding device is Perform the release process.

  Specifically, when a control signal for driving the X-axis feeding device 40 is received from the position command unit 14, the braking control unit 25 receives the control signal from the X-axis servo amplifier 18 while receiving the control signal. While allowing the current to be supplied to the X-axis servomotor 41, the current is appropriately supplied to the X-axis brake 44 to release the braking action.

  Further, when a control signal for driving the Y′-axis feeding device 40 is received from the position command unit 14, the brake control unit 25 receives the Y′-axis servo amplifier 19 while receiving the control signal. Is allowed to supply current to the Y′-axis servomotor 51, and current is appropriately supplied to the Y′-axis brake 44 to release the braking action.

  Similarly, when a control signal for driving the Z-axis feeding device 60 is received from the position command unit 14, the braking control unit 25 receives the control signal from the Z-axis servo amplifier 20 while receiving the control signal. While permitting current supply to the Z-axis servomotor 61, current is appropriately supplied to the Z-axis brake 64 to release the braking action.

  On the other hand, for the feeding device that does not receive the control signal, the braking control unit 25 supplies the current supplied from the numerical control unit 11 to the servo motor of the feeding device while not receiving the control signal related to the feeding device. And the brake of the feeder is operated to stop the rotation of the feed screw and the servo motor.

  Specifically, when a control signal for driving the X-axis feed device 40 is not received from the position command unit 14, the brake control unit 25 controls the X-axis servo amplifier 18 while the control signal is not received. Then, the current supplied from the X-axis servo amplifier 18 to the X-axis servo motor 41 is cut off, and the supply of current to the X-axis brake 44 is cut off, thereby causing the braking action. Thereby, the rotation of the X-axis feed screw 42 and the X-axis servo motor 41 is stopped.

  When the control signal for driving the Y′-axis feeding device 50 is not received from the position command unit 14, the brake control unit 25 turns the Y′-axis servo amplifier 19 on while the control signal is not received. By controlling, the current supplied from the Y′-axis servo amplifier 19 to the Y′-axis servomotor 51 is cut off, and the supply of current to the Y′-axis brake 54 is cut off to develop the braking action. . As a result, the rotation of the Y′-axis feed screw 52 and the Y′-axis servomotor 51 is stopped.

  Similarly, when a control signal for driving the Z-axis feeding device 60 is not received from the position command unit 14, the braking control unit 25 controls the Z-axis servo amplifier 20 while not receiving the control signal. Then, the current supplied from the X-axis servo amplifier 20 to the Z-axis servo motor 61 is cut off, and the supply of current to the Z-axis brake 64 is stopped to exhibit the braking action. Thereby, the rotation of the Z-axis feed screw (not shown) and the Z-axis servo motor 61 is stopped.

  According to the machine tool 1 of the present example having the above configuration, the program analysis unit 13 reads out an appropriate NC program in the program storage unit 12, and the read NC program is the program analysis unit 13. And a command such as a moving position and a feeding speed regarding each feed axis (X axis, generating Y axis and Z axis) is recognized, and a command such as the recognized moving position and feed speed is transmitted to the position command unit 14. The

  When the command relating to the moving position and the feed speed relating to each feed axis is transmitted from the program analysis unit 13 to the position command unit 14, the position command unit 14 sequentially generates a position command relating to the corresponding feed axis. The generated position command is transmitted to the corresponding X-axis control unit 15, Y′-axis control unit 16 and Z-axis control unit 17, and transmitted to the braking control unit 25.

  When a position command for the X-axis feeder 40 is generated by the position command unit 14, a control signal corresponding to the position command is transmitted from the X-axis control unit 15 to the X-axis servo amplifier 18, and then A drive current corresponding to this control signal is supplied from the X-axis servo amplifier 18 to the X-axis servo motor 41. At that time, while the brake control unit 25 receives a position command for the X-axis feeding device 40, the brake control unit 25 allows the supply of current from the X-axis servo amplifier 18 to the X-axis servo motor 41, and the X-axis brake. An appropriate current is supplied to 44 to release the braking action. Thereby, the X-axis servo motor 41 is driven according to the position command, and the turret 37 moves according to the position command.

  On the other hand, when the position command for the X-axis feed device 40 is not generated by the position command unit 14, that is, when the X-axis feed device 40 is in a stopped state, the braking control unit 25 during that time, The amplifier 18 is controlled so that the current supplied from the X-axis servo amplifier 18 to the X-axis servo motor 41 is cut off, and the supply of current to the X-axis brake 44 is cut off to develop the braking action. . Thereby, the rotation of the X-axis feed screw 42 and the X-axis servo motor 41 is stopped, and the movement of the tool post 36 in the X-axis direction is stopped.

  Similarly, when a position command for the Y′-axis feeding device 50 is generated by the position command unit 14, a control signal corresponding to the position command is transmitted from the Y′-axis control unit 16 to the Y′-axis servo amplifier 19. Then, a drive current corresponding to this control signal is supplied from the Y′-axis servo amplifier 19 to the Y′-axis servo motor 51. And while the said brake control part 25 is receiving the position command with respect to the Y 'axis | shaft feeder 50, while supplying the electric current from the said Y' axis servo amplifier 19 to the said Y 'axis servo motor 51, Y 'A current is appropriately supplied to the shaft brake 54 to release the braking action. As a result, the Y′-axis servomotor 51 is driven according to the position command, and the turret 37 moves according to the position command.

  On the other hand, when a position command for the Y′-axis feeding device 50 is not generated by the position command unit 14, that is, when the Y′-axis feeding device 50 is in a stopped state, the braking control unit 25 during that time, By controlling the “axis servo amplifier 19, the current supplied from the Y′-axis servo amplifier 19 to the Y′-axis servo motor 51 is cut off, and the current supply to the Y′-axis brake 54 is cut off, The braking action is expressed. As a result, the rotation of the Y′-axis feed screw 52 and the Y′-axis servo motor 51 is stopped, and the movement of the saddle 35 in the Y′-axis direction is stopped.

  Further, when a position command for the Z-axis feeding device 60 is generated by the position command unit 14, a control signal corresponding to the position command is transmitted from the Z-axis control unit 17 to the Z-axis servo amplifier 20. A drive current corresponding to this control signal is supplied from the Z-axis servo amplifier 20 to the Z-axis servo motor 61. While the brake control unit 25 receives a position command for the Z-axis feeding device 60, the brake control unit 25 allows the current to be supplied from the Z-axis servo amplifier 20 to the Z-axis servo motor 51, and a Z-axis brake 64. The braking action is released by supplying an appropriate current to As a result, the Z-axis servomotor 61 is driven according to the position command, and the carriage 34 moves according to the position command.

  On the other hand, when the position command to the Z-axis feeding device 60 is not generated by the position command unit 14, that is, when the Z-axis feeding device 60 is in a stopped state, the braking control unit 25 during that period, The amplifier 20 is controlled so that the current supplied from the Z-axis servo amplifier 20 to the Z-axis servomotor 61 is cut off, and the supply of current to the Z-axis brake 64 is cut off to develop the braking action. . Thereby, the rotation of the Z-axis feed screw (not shown) and the Z-axis servomotor 61 is stopped, and the movement of the carriage 34 in the Z-axis direction is stopped.

  As described above, according to the machine tool 1 of the present example, for a feeding device in which a control signal is not generated by the numerical control unit 11, that is, a feeding device in a state where the feeding operation is stopped, supply of power to the servo motor is performed. Since the position control is stopped and the feed screw is stopped by the brake, waste of electric power in the servo motor can be prevented and energy saving can be achieved.

  The tool post 36 and the turret 37 moved by the X-axis feed device 40, the saddle 35 moved by the Y′-axis feed device 50, and the carriage 34 moved by the Z-axis feed device 60 generally have a considerable weight. Therefore, the power supplied to the X-axis servo motor 41, the Y′-axis servo motor 51, and the Z-axis servo motor when performing position control to stop them at a predetermined position is considerably large. On the other hand, when driving the X-axis servo motor 41, the Y′-axis servo motor 51, and the Z-axis servo motor in a normal operation state, the X-axis brake 44, the Y′-axis brake 54, and the Z-axis brake 64 are released. Therefore, the power supplied to the X-axis brake 44, Y′-axis brake 54 and Z-axis brake 64 is the power supplied to the X-axis servo motor 41, Y′-axis servo motor 51 and Z-axis servo motor during the stop. Is much smaller than Therefore, even if the X-axis brake 44, the Y′-axis brake 54, and the Z-axis brake 64 are newly provided in the X-axis feeding device 40, the Y′-axis feeding device 50, and the Z-axis feeding device 60, the X-axis servo motor 41, When the Y′-axis servo motor 51 and the Z-axis servo motor are in a stopped state, the corresponding power can be saved by cutting off the power supply to them.

  Further, the machine tool 1 of the present example generates the Y axis direction that is a virtual feed axis orthogonal to the X axis and the Z axis by simultaneously operating the X axis feed device 40 and the Y ′ axis feed device 50 in synchronization. The turret 37 (that is, the tool T) can be moved to the center, and milling using the generating Y axis and turning without using the generating Y axis can be performed. When machining without using the generating Y-axis, the Y′-axis feeding device 50 that contributes only to the generation of the Y-axis is in a stopped state during this time. Therefore, if the electric power is continuously supplied to the Y′-axis feeding device 50 in the stopped state as described above, the supplied electric power is wasted. In addition, some workpieces are only turned and do not require milling. When machining such workpieces, the Y′-axis feed device 50 merely wastes electric power during the machining period. become.

  In this machine tool 1, when the generating Y-axis is not used, that is, when the Y′-axis feeding device 50 is in a stopped state, the braking control unit 25 performs the Y′-axis servo amplifier 19 to the Y′-axis servomotor during that time. Since the electric current supplied to 51 is interrupted, a larger energy can be reduced and a greater energy saving effect can be obtained.

  Further, the Y′-axis feeding device 50 has the feed screw 52 disposed horizontally, and the gravity of the saddle 35 does not act on the feed screw 52 in the axial direction. Similarly, the Z-axis feed device 61 has its feed screw (not shown) disposed horizontally, and the gravity of the carriage 34 acts on the feed screw (not shown) in the axial direction. Not. Therefore, the feed screw 42 is inclined and disposed as in the X-axis feed device 40, and the Y′-axis is compared to the case where the gravity of the tool post 36 and the turret 37 acts on the feed screw 42 in the axial direction. The brake 54 and the Z-axis brake 64 need only have a small braking force. Therefore, the power required for releasing the Y′-axis brake 54 and the Z-axis brake 64 is reduced, and the energy consumed when opening the Y′-axis brake 54 and the Z-axis brake 64 can be reduced. it can.

  As mentioned above, although one Embodiment of this invention was described, the specific aspect which this invention can take is not limited to this at all.

  For example, in the above example, the control signal generated by the position command unit 14 is transmitted to the braking control unit 25, and the braking control unit 25, based on this control signal, the X-axis feeding device 40 and the Y′-axis feeding device 50. The brake control unit 25 receives the control signal generated by the program analysis unit 13 and based on this control signal. The X-axis feeding device 40, the Y′-axis feeding device 50, and the Z-axis feeding device 60 may be configured to determine whether or not they are stopped.

  For example, when the program analysis unit 13 recognizes a command code related to the feed axis (X axis, generation Y axis, and Z axis) specified in each block of the NC program being executed, and generates a control signal related thereto. The brake control unit 25 receives the control signal and recognizes that the feeding device corresponding to the control signal is in an operating state while executing the block, and the current to the servo motor of the feeding device is And the process of releasing the brake of the feeder is performed.

  On the other hand, when executing the block, the brake control unit 25 executes the block for a feeding device in which the program analysis unit 13 does not generate a control signal and therefore the brake control unit 25 does not receive the control signal. In the meantime, the current supplied from the numerical controller 11 to the servo motor of the feeder is cut off, and the brake of the feeder is operated to stop the rotation of the feed screw and the servo motor.

  In this case, the braking control unit 25 determines whether or not the control signal transmitted from the program analysis unit 13 is a control signal related to the generating Y axis, and when receiving the control signal related to the generating Y axis, During the execution of the block, supply of current from the X-axis servo amplifier 18 to the X-axis servo motor 41 is allowed, and supply of current from the Y′-axis servo amplifier 19 to the Y′-axis servo motor 51 is allowed. While permitting, current is appropriately supplied to the X-axis brake 44 and the Y′-axis brake 54 to release the braking action. On the other hand, when the control signal related to the generating Y-axis is not received, the brake control unit 25 cuts off at least the current supplied from the Y′-axis servo amplifier 19 to the Y′-axis servo motor 51 while executing the block. At the same time, the supply of current to the Y′-axis brake 54 is interrupted to exert its braking action, and the rotation of the Y′-axis feed screw 52 and the Y′-axis servo motor 51 is stopped.

  Whether or not the control signal is related to the generating Y-axis is determined based on the control signal related to the movement position of the Y-axis that is directly commanded, the control signal related to the M code that rotates the tool, and the main shaft 33 used during cutting. The determination may be made based on an indirect control signal such as an M code related to the rotation command.

  In the above example, when the numerical control unit 11 executes the NC program, that is, in the automatic operation mode, the braking control unit 25 causes the numerical control unit 11 to send the feeding device in operation. The servo motor is allowed to supply current and the brake of the feeder is released. On the other hand, the stopped feeder is supplied from the numerical controller 11 to the servo motor of the feeder. While the current is cut off and the brake of the feed device is operated to stop the rotation of the feed screw and the servo motor, the present invention is not limited to this.

  For example, a manual operation signal for driving the X-axis feeding device 40, the Y′-axis feeding device 50, and the Z-axis feeding device 60 is input from the operation panel for manual operation to the numerical control unit 11, and this manual operation signal is converted to the manual operation signal. The position command unit 14 receives the position command unit 14 and generates a control signal corresponding to the manual operation signal. Based on the control signal, the X-axis control unit 15, the Y′-axis control unit 16, and the Z-axis The control unit 17 drives the corresponding X-axis servo motor 41, Y′-axis servo motor 51, and Z-axis servo motor 61 via the X-axis servo amplifier 18, Y′-axis servo amplifier 19 and Z-axis servo amplifier 20, respectively. In the case of control, the braking control unit 25 receives a control signal generated by the position command unit 14 in response to a manual operation signal, and receives an X-axis feeding device 40, a Y′-axis feeding device 50, and a Z-axis feeding device. 60 stops It may be configured to determine whether the state.

  In this case, that is, in a state where the main power is turned on, when the numerical control unit 11 is in an operation mode other than the automatic operation mode, when the manual operation signal is not input from the operation panel to the numerical control unit 11, the position Since the control signal is not generated by the command unit 14, the braking control unit 25 receives the X-axis from the numerical control unit 11 until the manual operation signal is input, in other words, while the manual operation signal is not input. The current supplied to the servo motor 41, the Y′-axis servo motor 51, and the Z-axis servo motor 61 is cut off, and the X-axis brake 44, the Y′-axis brake 54, and the Z-axis brake 64 are operated to 42, stop the rotation of the Y′-axis feed screw 52, the Z-axis feed screw (not shown), the X-axis servo motor 41, the Y′-axis servo motor, and the Z-axis servo motor 61. . It is in this state when the main power supply is turned on.

  On the other hand, in a state where the main power is turned on, when the numerical control unit 11 is in an operation mode other than the automatic operation mode, a manual operation signal is input from the operation panel to the numerical control unit 11 and the position command unit 14 controls the control signal. When the control signal is generated, the braking control unit 25 receives the control signal, and the sending device that has received the control signal receives the control signal from the numerical control unit 11 while receiving the control signal. While permitting current supply to the servo motor of the apparatus, the brake of the feeder is released.

  In the state where the operator is performing the setup work of the machine tool 1, the numerical control unit 11 is in a mode other than the automatic operation mode. However, according to this configuration, the numerical control unit 11 is in a stopped state in a mode other than the automatic operation mode. The supply of current to the servo motor of the feeding device can be cut off, and waste of electric power can be prevented.

  In the above example, the X-axis brake 44, the Y′-axis brake 54, and the Z-axis brake 64 are composed of electromagnetic brakes. However, the present invention is not limited to this. In this case, any mechanism may be used as long as the brake is in a braking state, and various types such as a hydraulic brake can be employed.

DESCRIPTION OF SYMBOLS 1 Machine tool 10 Control apparatus 11 Numerical control part 12 Program memory | storage part 13 Program analysis part 14 Position command part 15 X-axis control part 16 Y'-axis control part 17 Z-axis control part 18 X-axis servo amplifier 19 Y'-axis servo amplifier 20 Z-axis servo amplifier 30 Motion mechanism section 31 Bed 32 Spindle base 33 Spindle 34 Reciprocating base 35 Saddle 36 Tool post 37 Turret 40 X-axis feed device 41 X-axis servo motor 42 X-axis feed screw 44 X-axis brake 50 Y'-axis feed device 51 Y′-axis servo motor 52 Y′-axis feed screw 54 Y′-axis brake 60 Z-axis feed device 61 Z-axis servo motor 64 Z-axis brake T Tool

Claims (4)

Each of the feed screw, a servo motor that drives the feed screw, and a plurality of feed devices each having a brake that stops rotation of the feed screw or the servo motor, and generates a control signal for each feed device, A machine tool including a numerical control unit that supplies the corresponding current to the corresponding servo motor to numerically control its operation,
The control signal related to each of the feeding devices generated by the numerical control unit is sequentially received from the numerical control unit,
For the feeding device that has received the control signal, while the control signal is being received, supply of current from the numerical control unit to the servo motor of the feeding device is permitted, and the brake of the feeding device is released. ,
For the feeding device that does not receive the control signal, while not receiving the control signal related to the feeding device, the current supplied from the numerical control unit to the servo motor of the feeding device is cut off, and the feeding device A machine tool comprising a braking control unit configured to operate a brake to stop rotation of a servo motor or a feed screw. The first feed shaft is disposed in the same plane as the first feed shaft, the first feed device having the feed screw disposed along the first feed shaft, and moving the moving body along the first feed shaft. The feed screw is disposed along a second feed shaft that intersects in a non-orthogonal state with at least a second feed device that moves the first feed device along the second feed shaft,
The numerical control unit operates the first feeding device and the second feeding device at the same time so as to move the moving body along a virtual feeding axis orthogonal to the first feeding axis or the second feeding axis. The machine tool according to claim 1, wherein the machine tool is configured.   The machine tool according to claim 2, wherein the first feed device or the second feed device has the feed screw disposed horizontally. The machine tool according to any one of claims 1 to 3, wherein the brake is constituted by an electromagnetic brake that enters a non-braking state when current is supplied and enters a braking state when the current is interrupted.

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