Automatic tool changer of machine tool and control method thereof

Abstract

The present invention relates to an automatic tool changer for a machine tool and a method for controlling the same, which, when generating a tool changing command, can change the rotational speed of a jaw unit in multiple stages according to the number of tool pockets to be changed and the calculated number of revolutions of the jaw unit, thereby enabling the tool to be changed in multiple stages when one edge of the tool pocket is moved even if a gear motor is used. A tool is automatically replaced without stop.

Description

Technical Field

[0001] The present invention relates to an automatic tool changing device for a machine tool and a control method thereof, and more specifically, to an automatic tool changing device for a machine tool and a control method thereof. When a tool changing instruction is generated, the rotation speed of the clamping claw unit is changed in multiple stages according to the serial number of the tool sleeve to be replaced and the calculated number of rotations of the clamping claw unit, so that even if a gear motor is used, the tool can be automatically changed without stopping when one of the cutting edges of the tool sleeve is moved. Background Art

[0002] Generally, a machine tool refers to a machine used to process metal / non-metal workpieces into a desired shape and size using various cutting or non-cutting methods using appropriate tools.

[0003] Various types of machine tools such as turning centers, vertical / horizontal machining centers, portal machining centers, switch turns, electrical discharge machines, horizontal NC drilling machines, CNC lathes, and multi-tasking machine tools are widely used in various industrial sites according to the purpose of the corresponding operations.

[0004] Among machine tools, a multi-tasking machine tool refers to a turning center equipped with a multifunctional automatic tool changer (ATC) and a tool magazine that performs various functions, and can perform a variety of processing types such as turning, drilling, tapping, milling, etc. When workers load or replace the tools required for processing on a multi-tasking machine tool, they manually install the tools into the tool magazine.

[0005] Generally, many machine tools currently in use are equipped with a control console using numerical control (NC) or CNC (computerized numerical control) technology, which has a variety of function switches or buttons and a monitor.

[0006] In addition, the machine tool is equipped with: a transfer table for placing the workpiece, i.e., the material, and transferring the workpiece for processing; a pallet for preparing the workpiece before processing; a spindle for rotating in conjunction with the tool or the workpiece; a tailstock for supporting the workpiece during processing; and a shockproof device.

[0007] Generally, in a machine tool, a transfer table, a tool rest, a spindle, a tailstock, a vibration-proof device, etc. are provided with a transfer unit that transfers along a transfer axis to perform various types of processing.

[0008] In general, a machine tool uses a plurality of tools to perform various types of machining, and also uses a tool magazine or a turret in the form of a tool storage location for accommodating and storing the plurality of tools.

[0009] These machine tools use a plurality of tools to perform various types of machining, and also use a tool magazine in the form of a tool storage area for accommodating and storing the plurality of tools.

[0010] In addition, in order to minimize non-processing time, the machine tool is generally equipped with an automatic pallet changer (APC). The automatic pallet changer (APC) automatically changes the pallet between the workpiece processing area and the workpiece setting area. The workpiece can be loaded on the pallet.

[0011] Generally, in order to improve the productivity of a machine tool, the machine tool is equipped with an automatic tool changer (ATC), which extracts or re-accommodates a specific tool from a tool magazine in response to a command from a numerical control unit.

[0012] Generally, the tool magazines used in machine tools, especially machining centers and turning centers, can be roughly divided into two types: one is the drum type tool magazine, and the other is the chain type tool magazine.

[0013] In addition, conventionally used automatic tool changers (ATCs) are classified into arm type and armless type according to the method of clamping the tool.

[0014] These arm-type and armless-type automatic tool changing devices usually change tools by means of a rotating plate on which a plurality of tool pockets equipped with tools are arranged.

[0015] That is, in order to rotate the rotating plate, the rotating plate of the tool magazine is rotated by a gear motor or a servo motor.

[0016] However, when the automatic tool changing device of the existing machine tool uses a gear motor, a barrel cam dwelling section occurs each time the tool holder moves a cutting edge. Therefore, there is a problem of not being able to rotate continuously and temporarily stopping the movement, which will lead to an increase in tool changing time, a decrease in productivity as the non-machining time increases, and an increase in machining costs.

[0017] In addition, when the automatic tool changing device of the existing machine tool adopts a gear motor, a dwelling section will occur, which will lead to increased vibration, reduced processing accuracy, and reduced stability and reliability.

[0018] Moreover, when the automatic tool changing device of the existing machine tool uses a servo motor, various additional devices must be equipped to control the servo drive and the servo motor, which will lead to increased manufacturing costs, consumer dissatisfaction, and a decrease in export rate.

[0019] Therefore, there is an urgent need to develop an automatic tool changing device for a machine tool that can perform tool replacement without dwelling while using a gear motor and a control method thereof. Summary of the invention

[0020] Technical issues

[0021] The present invention is proposed to solve the above-mentioned problem, and its purpose is to provide an automatic tool changing device for a machine tool and a control method thereof. According to the generated tool changing instruction, the first clamping claw unit is rotated at a basic speed by a number less than the number of the tool holder to be replaced by one. When the counting result shows that the first clamping claw unit has rotated by a number less than the number of the tool holder to be replaced by one, the motor is decelerated to a first-stage deceleration speed, and a second sensor unit for sensing the rotation of the second clamping claw unit is activated. Then, according to the counting result, the first clamping claw unit performs the final rotation of the number of the tool holder to be replaced at the first-stage deceleration speed. When the first sensing interval enters the first sensor unit, the motor is decelerated to the secondary deceleration speed, and when the second sensor unit senses the second sensing interval, it is recognized that the tool holder to be replaced is in the correct position, and the motor is stopped. Then, the DC braking of the inverter unit is started to stop the tool magazine from rotating. After a predetermined time, the DC braking is released and the motor brake is started to perform tool replacement. Thus, the rotation speed of the claw unit is changed to multiple levels according to the counted number of rotations of the claw unit. Therefore, even if a gear motor is used, the tool can be automatically replaced when one of the blades of the tool holder is moved.

[0022] Technical Solution

[0023] To achieve the purpose of the present invention, the automatic tool changing device of the machine tool according to the present invention may be, comprising: a tool magazine, provided with a plurality of tool sleeves, and rotatably arranged; a driving unit, used to generate the rotational power of the tool magazine; a rotating unit, linked with the rotation of the driving unit, so that the tool magazine rotates; a claw unit, installed on the rotating unit, and rotates with the rotation of the rotating unit; a sensor unit, arranged adjacent to the claw unit, and sensing the claw unit; an inverter unit, driving the driving unit by applying current to the driving unit; and a control unit, used to control tool replacement, when a tool replacement instruction is generated, the control unit confirms the number of rotations and the correct position of the claw unit counted from the sensor unit, and adjusts the Hertz applied from the inverter unit to the driving unit, thereby changing the rotation speed of the driving unit in multiple stages while rotating the tool magazine to perform tool replacement.

[0024] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, it may be that in the automatic tool changing device, the tool holder moves one cutting edge every time the rotating unit rotates one circle, and regardless of the type of the motor of the driving unit, when the tool holder for tool replacement is specified according to the tool change instruction, the rotating unit rotates continuously until the tool holder to be replaced moves to the tool change position.

[0025] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool of the present invention, the jaw unit may include: a first jaw unit, having a first sensing area protruding along a circumferential direction, and installed on the rotating unit, and rotating with the rotation of the rotating unit; and a second jaw unit, having a second sensing area protruding along a circumferential direction, and being arranged on the rotating unit in sequence with the first jaw unit, and rotating in conjunction with the first jaw unit.

[0026] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, the sensor unit may include: a first sensor unit, which is arranged adjacent to the first jaw unit to sense the first jaw unit through the first sensing interval when the first jaw unit rotates; and a second sensor unit, which is arranged adjacent to the second jaw unit to sense the second jaw unit through the second sensing interval when the second jaw unit rotates.

[0027] Furthermore, according to another preferred embodiment of the automatic tool changing device for a machine tool according to the present invention, the circumference of the first sensing section may be formed to be larger than the circumference of the second sensing section.

[0028] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, it may be that the control unit senses and counts through the first sensor unit whether the first jaw unit rotates at a basic speed according to the tool change instruction generated by one less than the number of the tool holder to be replaced, and when the counting result shows that the first jaw unit has rotated by one less than the number of the tool holder to be replaced, the motor is decelerated to a first-level deceleration speed, and at the same time, the second sensor unit is activated so that the second sensor unit senses the rotation of the second jaw unit.

[0029] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, it may be that, according to the counting result, when the first jaw unit performs the last rotation of the numbered tool holder of the replacement object at the first-level deceleration speed, the control unit decelerates the motor to the second-level deceleration speed at the moment when the first sensing interval enters the first sensor unit, and when the second sensor unit senses the second sensing interval, it recognizes that the tool holder of the replacement object is in the correct position, stops the motor, operates the DC braking of the inverter unit, and makes the tool magazine stop rotating. After a predetermined time, the DC braking is released and the motor brake is started.

[0030] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, it may be that the control unit, when generating a tool changing instruction, releases the motor brake and rotates the motor at a basic speed before the first sensor unit senses the rotation of the first claw unit.

[0031] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, the primary deceleration speed may be a speed slower than the basic speed, and the secondary deceleration speed may be a speed slower than the primary deceleration speed.

[0032] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool of the present invention, the tool magazine may include: a base portion; a drum rotatably arranged on the base portion; and a plurality of tool sleeves arranged at predetermined intervals along the circumferential direction of the drum for accommodating tools.

[0033] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, the driving unit may include: a motor, which is arranged on the base and started by the current applied by the inverter unit; a rotating shaft, which is inserted into and connected to the motor and rotates as the motor rotates; a motor brake, which is arranged on the motor to prevent the rotation of the motor under the control of the control unit; and a transmission unit, which is arranged on one side of the rotating shaft to transmit the rotational force.

[0034] Moreover, according to other preferred embodiments of the automatic tool changing device of a machine tool according to the present invention, the rotating unit may include: a camshaft, which is rotatably arranged on the base portion and parallel to the rotating shaft; a cylindrical cam, which is formed in a spiral shape along the circumferential direction without a horizontal section along the axial direction of the camshaft; and a connecting portion, which is arranged on one side of the camshaft, connected to the transmission unit through gear meshing, and rotates with the rotation of the rotating shaft.

[0035] Furthermore, according to another preferred embodiment of the automatic tool changing device for a machine tool according to the present invention, the motor may be a gear motor.

[0036] To achieve another purpose of the present invention, the control method of the automatic tool changing device of the machine tool according to the present invention may be that when the rotating unit rotates one circle, the tool holder of the tool magazine moves one cutting edge to perform tool change, including: when generating a tool change instruction, confirming the rotation number of the first claw unit from the first sensor unit and the correct position of the second claw unit from the second sensor unit, and adjusting the current applied from the inverter unit to the motor of the drive unit to change the rotation speed of the drive unit to multiple levels, and at the same time, storing data of the rotating unit for performing tool change; generating a tool change instruction for tool change of the tool magazine; calculating the number of rotations less than the number of the tool holder to be replaced according to the generated tool change instruction; releasing the motor brake; operating the motor at a basic speed to rotate the drive unit; the first sensor unit sensing whether the first claw unit is rotating to The steps of counting the number of rotations; when the counting result shows that the first claw unit has completed a number of rotations less than the number of the tool holder to be replaced, the motor is decelerated to the first deceleration speed, and the rotating unit is decelerated to the first deceleration speed; the step of activating the second sensor unit so that the second sensor unit senses the rotation of the second claw unit; the step of counting the result shows that when the first claw unit performs the last rotation of the tool holder number to be replaced at the first deceleration speed, the first sensing interval of the first claw unit decelerates the motor to the second deceleration speed at the moment of entering the first sensor unit; if the second sensor unit senses the second sensing interval of the second claw unit, the step of stopping the motor and placing the tool holder to be replaced in the correct position; the step of operating the DC brake of the inverter unit to stop the rotation of the tool magazine; and the step of performing tool replacement according to a tool replacement instruction.

[0037] Moreover, according to the control method of the automatic tool changing device of the machine tool of the present invention, after the step of operating the DC braking of the inverter unit to stop the rotation of the tool magazine, it may also include: while operating the DC braking of the inverter unit, releasing the DC braking of the inverter unit after a predetermined time and starting the motor brake.

[0038] Effects of the Invention

[0039] According to the automatic tool changing device of a machine tool and the control method thereof of the present invention, according to the generated tool changing instruction, the first clamping claw unit is rotated at a basic speed by a number less than the number of the tool sleeve to be replaced by one. When the counting result shows that the first clamping claw unit has rotated by a number less than the number of the tool sleeve to be replaced by one, the motor is decelerated to a first-stage deceleration speed and the second sensor unit for sensing the rotation of the second clamping claw unit is activated. Then, when the counting result shows that the first clamping claw unit makes the last rotation of the number of the tool sleeve to be replaced at the first-stage deceleration speed, the motor is decelerated to a second-stage deceleration speed at the moment when it enters the first sensor unit in the first sensing interval. The speed is determined, and when the second sensor unit senses the second sensing interval, it is recognized that the tool holder to be replaced is in the correct position, and the motor is stopped. Then, the DC braking of the inverter is started to stop the tool magazine from rotating. After a predetermined time, the DC braking is released, and the motor brake is started to perform tool replacement. Thus, according to the counted number of rotations of the claw unit, the rotation speed of the claw unit is changed into multiple levels. Thus, even if a gear motor is used, the tool can be automatically replaced without stopping when one of the blades of the tool holder is moved. Therefore, it has the effect of reducing tool change time and non-processing time, saving processing costs, and improving productivity.

[0040] Moreover, according to the automatic tool changing device of the machine tool and its control method of the present invention, the tool can be changed without a stop section using only a gear motor, an inverter unit and a control unit without a servo motor, thereby preventing vibration, improving processing accuracy, and improving the safety and reliability of the machine tool.

[0041] Furthermore, according to the automatic tool changing device of a machine tool and the control method thereof of the present invention, since a servo motor is not required, it is possible to save manufacturing costs and improve customer satisfaction.

[0042] In addition, according to the automatic tool changing device of the machine tool and its control method of the present invention, the tool can be changed without stopping by using only the simple components of a gear motor, an inverter unit, a control unit, a claw unit and a sensor unit. Thus, it is possible to miniaturize the automatic tool changing device, reduce manufacturing costs and maximize space utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A conceptual diagram showing an automatic tool changing device for a machine tool according to the present invention.

[0044] Figure 2 A front perspective view of an automatic tool changing device for a machine tool according to an embodiment of the present invention is shown.

[0045] Figure 3 Show Figure 2 A rear perspective view of the center tool magazine with the drum and tool pocket removed.

[0046] Figure 4 Show Figure 3 A three-dimensional view of the base of the tool magazine is attached with it removed.

[0047] Figure 5 Show Figure 4 Top view of the .

[0048] Figure 6 Shown along Figure 5 Cross-sectional view along line AA.

[0049] Figure 7 Shown along Figure 5 Cross-sectional view of line BB.

[0050] Figure 8 A conceptual diagram showing a startup process according to a startup sequence of an automatic tool changing device of a machine tool according to an embodiment of the present invention.

[0051] Fig. 9 A flow chart showing a control method of an automatic tool changing device of a machine tool according to the present invention. DETAILED DESCRIPTION

[0052] Below, the automatic tool changing device of a machine tool and the control method thereof according to an embodiment of the present invention are described in detail with reference to the figure. The embodiments introduced below are provided as examples to fully convey the idea of ​​the present invention to those skilled in the art. Therefore, the present invention is not limited to the embodiments described below, and can be embodied in other forms. Moreover, in the figures, the size and thickness of the device can be magnified for convenience. Throughout the specification, the same symbols represent the same components.

[0053] The advantages, features and techniques of achieving the advantages, features and techniques of the present invention will be made clear by the accompanying drawings and the embodiments described below. However, the present invention is not limited to the following embodiments and can be embodied in various other forms. This embodiment makes the disclosure of the present invention more complete and provides a complete scope of the invention to those skilled in the art to which the present invention belongs. Throughout the specification, the same symbols represent the same constituent elements. For the purpose of clarity, the sizes and relative sizes of the layers and regions in the figures may be enlarged.

[0054] The terms used in this specification are used to illustrate the embodiments and do not limit the present invention. When not specifically mentioned in this specification, the singular form also includes the plural form. The terms "comprise" and / or "comprising" used in the specification mean that the mentioned constituent elements, steps, actions and / or components do not exclude the existence or addition of one or more other constituent elements, steps, actions and / or components.

[0055] Figure 1 A conceptual diagram showing an automatic tool changing device for a machine tool according to the present invention. Figure 2 A front perspective view of an automatic tool changing device for a machine tool according to an embodiment of the present invention is shown. Figure 3 Show Figure 2 A rear perspective view of the center tool magazine with the drum and tool pocket removed. Figure 4 Show Figure 3 A three-dimensional view of the base of the tool magazine is attached with it removed. Figure 5 Show Figure 4 Top view of the . Figure 6 Shown along Figure 5 Cross-sectional view along line AA. Figure 7 Shown along Figure 5 Cross-sectional view of line BB. Figure 8 A conceptual diagram showing a startup process according to a startup sequence of an automatic tool changing device of a machine tool according to an embodiment of the present invention. Fig. 9 A flow chart showing a control method of an automatic tool changing device of a machine tool according to the present invention.

[0056] Will refer to Figures 1 to 8 The automatic tool changing device 1 of a machine tool according to an embodiment of the present invention is described. Figures 1 to 7 As shown, the automatic tool changing device 1 of a machine tool according to the present invention comprises: a tool magazine 10, a driving unit 20, a rotating unit 30, a claw unit 40, a sensor unit 50, an inverter unit 60, and a control unit 70.

[0057] The tool magazine 10 includes a plurality of tool pockets and is rotatably provided.

[0058] That is, Figures 1 to 3 As shown, a tool magazine 10 of an automatic tool changing device for a machine tool according to a preferred embodiment of the present invention comprises: a base portion 11 , a roller 12 , and a tool sleeve 13 .

[0059] The base 11 forms the outer shape of the tool magazine rear, and is formed into a frame shape, and is installed on a part of the machine tool. That is, the base is arranged at the rear of the tool magazine, and provides a space for installing a roller, a drive unit, a rotation unit, a claw unit, and a sensor unit described later.

[0060] The drum 12 is rotatably disposed on the base portion. That is, the drum is formed in a disc shape and is rotatably mounted on the base portion.

[0061] A plurality of tool sleeves 13 are arranged at predetermined intervals along the circumferential direction of the drum to accommodate tools 14. In this way, by accommodating a plurality of tools in the plurality of tool sleeves, tools can be replaced as workpieces are processed, thereby achieving convenience for the staff, shortening processing time, improving productivity, and reducing processing costs.

[0062] The driving unit 20 generates the rotational power of the tool magazine. That is, the driving unit is used to generate the power to rotate the drum.

[0063] like Figures 1 to 7 As shown, the driving unit 20 of the automatic tool changing device of a machine tool according to a preferred embodiment of the present invention includes: a motor 21, a driving shaft 22, a transmission unit 23, and a motor brake 24.

[0064] The motor 21 is mounted on the base portion and is started by the current applied from the inverter unit. The motor of the driving unit of the automatic tool changing device of the machine tool according to the preferred embodiment of the present invention is formed by a gear motor. That is, instead of using a servo motor, a gear motor type can be used, which is a kind of induction motor with a built-in reduction gear and can be accelerated and decelerated by an inverter unit. Therefore, it can be driven without other servo drives or additional servo motor control devices, thereby reducing manufacturing costs, promoting miniaturization, and improving consumer satisfaction.

[0065] The rotating shaft 22 is inserted into and coupled to the motor, and rotates as the motor rotates.

[0066] The transmission unit 23 is installed on one side of the rotating shaft and transmits the rotational force. That is, the transmission unit is formed in the form of a spur gear on one side of the rotating shaft and is connected to the connection part of the rotating unit described later through gear meshing to transmit the rotational power of the rotating shaft to the rotating unit.

[0067] The motor brake 24 is mounted on the motor and blocks the rotation of the motor under the control of the control unit. That is, the motor brake is mounted on the motor and can be formed in various forms such as to block the rotation of the motor or the rotation of the rotating shaft according to the control of the control unit.

[0068] The rotation of the rotating unit 30 and the driving unit are linked to rotate the tool magazine. That is, the rotating unit 30 rotates with the rotation of the driving unit through the transmission unit of the driving unit, and finally rotates the tool magazine, so that the tool sleeve arranged at a predetermined angle in the circumferential direction of the tool magazine rotates and moves to the replacement position to perform tool replacement.

[0069] like Figures 1 to 7 As shown, the rotating unit 30 of the automatic tool changing device of a machine tool according to a preferred embodiment of the present invention includes: a cam shaft 31, a cylindrical cam 32, and a connecting portion 33.

[0070] The cam shaft 31 is rotatably disposed on the base portion in parallel with the rotation axis.

[0071] The barrel cam 32 is formed in a spiral shape in the circumferential direction without a horizontal section along the axial direction of the cam shaft.

[0072] The connection portion 33 is disposed at one side of the camshaft, connected to the transmission unit through gear meshing, and rotates as the rotation shaft rotates.

[0073] Therefore, the cylindrical cam is formed in the form of a spiral groove along the circumferential direction of the cylindrical cam shaft, and the spiral groove is formed so that the axial phase does not change when the cam shaft rotates, and the axial phase changes continuously without a dwelling section, so that when the cam shaft rotates by the rotational force transmitted from the connection part, it rotates continuously, and the drum of the tool magazine is continuously rotated by the cam guided by the cylindrical cam. In addition, the number of these cams is formed to correspond to the number of tool sleeves provided on the drum.

[0074] The claw unit 40 is mounted on the rotating unit, and rotates as the rotating unit rotates.

[0075] The sensor unit 50 is disposed adjacent to the claw unit and is used to sense the claw unit.

[0076] The inverter unit 60 drives the drive unit by applying current to the drive unit. That is, the inverter unit can not only drive the drive unit by adjusting the amount of current applied to the motor of the drive unit through the control of the control unit, but also limit the rotation of the motor through the DC braking of the inverter unit as needed. Specifically, the inverter unit adjusts the Hertz applied to the drive unit.

[0077] The control unit 70 controls tool replacement. When a tool replacement command is generated, the control unit of the present invention confirms the number of rotations and the correct position of the claw unit counted from the sensor unit, and adjusts the Hertz applied from the inverter unit to the drive unit, thereby changing the rotation speed of the drive unit in multiple stages while rotating the tool magazine to perform tool replacement.

[0078] That is, the tool magazine moves one opening each time the rotary unit rotates one circle. Regardless of the type of the motor of the drive unit, when the tool magazine for tool replacement is designated according to the tool replacement command, the rotary unit rotates continuously until the replacement target tool magazine moves to the tool replacement position.

[0079] The control unit includes NC (numerical control, NC) or CNC (computerized numerical control) and PLC, and has various numerical control programs built in. That is, the control unit has built-in processing programs and driver programs and startup programs for processing units, drive units, transfer units, etc. By operating the control unit, the corresponding programs are automatically loaded and run. In addition, the control unit communicates with the drive unit, processing unit, sensor unit, inverter unit and PLC through a predetermined protocol.

[0080] In addition, although not shown in the figures, according to a preferred embodiment of the present invention, the control unit includes a main operating unit, and the main operating unit includes a screen display program and a data input program selected according to the screen display. According to the output of the screen display program, a software switch is displayed on the display screen, the ON / OFF state of the software switch is identified, and the function of issuing input / output instructions for machine operation is executed.

[0081] In addition, although not necessarily limited thereto, the main operating unit is installed on the casing of the machine tool, the housing of the control unit, or one side of the machine tool or the control unit, and includes various function switches or buttons and a monitor capable of displaying various information.

[0082] In addition, although not shown in the figure, the control unit of the automatic tool changing device of the machine tool of the present invention may include a display unit, which displays in real time the tool change instruction, the tool holder to be replaced, the tool holder in the replacement position, the rotation speed of the motor, the sensing result of the sensor unit, the number of rotations of the first jaw unit, etc., thereby improving the convenience of users or staff.

[0083] These display units may include at least one of a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT LCD), an organic light-emitting diode (OLED), a flexible display, a 3D display or an electronic ink display (e-ink display).

[0084] In addition, although not necessarily limited thereto, the display unit is formed in the form of a touch screen and can be installed on the housing of the machine tool or control unit, or on one side of the machine tool or control unit to display various function switches or buttons and various information.

[0085] Therefore, the automatic tool changing device of the machine tool according to the present invention only uses a gear motor, an inverter unit and a control unit instead of a servo motor, and can realize tool replacement without a stop section without a servo motor, etc., thereby preventing vibration, improving processing accuracy, and improving the safety and reliability of the machine tool. Since the servo motor is not used, the manufacturing cost can be reduced and the consumer satisfaction can be improved.

[0086] like Figures 1 to 7As shown, the jaw unit 40 of the automatic tool changing device of a machine tool according to a preferred embodiment of the present invention includes a first jaw unit 41 and a second jaw unit 42 , and the sensor unit 50 includes a first sensor unit 51 and a second sensor unit 52 .

[0087] The first claw unit 41 includes a first sensing area R1 protruding in the circumferential direction, and is disposed on the rotating unit to rotate as the rotating unit rotates.

[0088] That is, the first claw unit is axially inserted into the cam shaft of the rotating unit, and rotates as the cam shaft of the rotating unit rotates.

[0089] In addition, the first claw unit has a specified diameter as a whole and is formed into a roughly disc-shaped or elliptical shape close to a circle. When the first claw unit rotates, the first sensor unit of the sensor unit described later is easily sensed, and the first sensing interval protrudes a predetermined circumferential length in the circumferential direction of the first claw unit.

[0090] The second claw unit 42 has a second sensing area R2 protruding in the circumferential direction, is disposed on the rotating unit in sequence with the first claw unit, and rotates in conjunction with the first claw unit.

[0091] That is, the second claw unit and the first claw unit are sequentially inserted and arranged on the cam shaft of the rotating unit in the axial direction, and rotate in the same direction and speed as the cam shaft of the rotating unit and the first claw unit rotate.

[0092] In addition, the second claw unit as a whole has a predetermined diameter and is formed into a disc shape or an elliptical shape close to a circle. When the second claw unit rotates, the second sensor unit of the sensor unit described later is easily sensed, and the second sensing interval protrudes a predetermined circumferential length in the circumferential direction of the second claw unit.

[0093] In addition, the first sensor unit 51 is disposed adjacent to the first claw unit to sense the first claw unit through the first sensing section when the first claw unit rotates. That is, the first sensor unit is disposed adjacent to the first claw unit on the base portion or the rotating unit.

[0094] In addition, the first sensor unit is formed by a proximity sensor. When the first claw unit rotates, the rotation of the first claw unit is sensed by passing through the first sensing interval of the first claw unit rotating through the first sensor unit, and the number of rotations of the first claw unit is counted. Since the circumference of the first sensing interval is formed to be longer than the circumference of the second sensing interval, a signal is transmitted to the control unit at the moment of passing through the first sensing interval to change the rotation speed of the motor.

[0095] The second sensor unit 52 is disposed adjacent to the second claw unit, and senses the second claw unit through the second sensing section when the second claw unit rotates. That is, the second sensor unit is disposed adjacent to the second claw unit on the base portion or the rotating unit.

[0096] In addition, the second sensor unit is formed by a proximity sensor. When the second claw unit rotates, the second sensor unit senses the rotation of the second claw unit through the second sensing interval of the second claw unit rotating through the second sensor unit, confirms the correct position, and transmits a motor stop signal to the control unit.

[0097] In addition, the circumference of the first sensing section of the first jaw unit of the automatic tool changing device of the machine tool according to one embodiment of the present invention is formed to be larger than the circumference of the second sensing section of the second jaw unit. That is, since the circumference of the first sensing section of the first jaw unit is formed to be larger than the circumference of the second sensing section of the second jaw unit, the first jaw unit has a counting jaw function, and the second sensor unit can sense the rotation of the second jaw unit according to the number of rotations of the first jaw unit, so that the correct position can be confirmed simply, quickly and accurately.

[0098] According to the automatic tool changing device of the machine tool of the present invention, the tool can be replaced without stopping by using only the simple structure of the gear motor, inverter unit, control unit, claw unit and sensor unit. Thus, the automatic tool changing device can be miniaturized, the manufacturing cost can be reduced, and the space utilization can be maximized.

[0099] refer to Figures 1 to 8 , the automatic tool changing device of a machine tool according to the present invention and the starting principle of the automatic tool changing according to the control method thereof will be explained.

[0100] The data storage unit of the control unit stores a workpiece processing program, information about the tools contained in each tool holder, tool holder information, etc., and stores a tool replacement program for processing the workpiece based on the stored information.

[0101] In addition, when the inverter unit adjusts the hertz applied to the motor of the driving unit, the rotation speed of the motor of the driving unit is stored as a basic speed V1, a primary reduction speed V2, and a secondary reduction speed V3.

[0102] Preferably, the primary deceleration speed V2 is designated as a speed slower than the basic speed V1 , and the secondary deceleration speed V3 is designated as a speed slower than the primary deceleration speed V2 .

[0103] For example, the current applied from the inverter to the motor can actually be adjusted by adjusting the Hertz (Hz). The larger the Hertz, the faster the speed. Therefore, the basic speed is specified as 75Hz, the first reduction speed is 10Hz, and the second reduction speed is 3Hz.

[0104] According to the machining program and the tool change program, the control unit generates a tool change instruction according to the current workpiece machining state. Figures 2 to 8 , the case where a tool change instruction is generated at T8 according to a tool change instruction when the position of T1 is the tool change position will be described as an example.

[0105] According to the tool change command, the number of rotations is calculated according to the position of the tool holder to be replaced. That is, when the motor rotates one turn, the rotary shaft rotates one turn, and when the rotary shaft rotates one turn, the camshaft rotates one turn, and when the camshaft rotates one turn, the tool holder rotates one blade. Therefore, according to the tool change command, when the tool holder to be replaced is T8, the number of rotations is 7.

[0106] Thereafter, when the control unit generates a tool change command, the motor brake is released by a control signal from the control unit before the first sensor unit senses the rotation of the first jaw unit. Figure 8 As shown, after a certain period of time (500ms), the motor is rotated at the basic speed (75Hz, V1).

[0107] When the motor rotates at the base speed, the transmission unit and the connecting portion of the rotating unit that are gear-engaged with the rotating shaft of the motor rotate, and as the connecting portion rotates, the camshaft rotates at the same base speed as the motor. Figure 8 As shown, the first jaw unit and the second jaw unit rotate at a basic speed.

[0108] When the motor rotates at the basic speed, the control unit senses through the first sensor unit whether the first jaw unit rotates at the basic speed according to the generated tool change instruction, and counts the number (N-1) that is one less than the number (N) of the tool holder to be replaced. That is, each time the first sensing interval of the first jaw unit passes through the first sensor unit once, the first sensor unit is counted to rotate one circle. Specifically, when the T8 position is changed, the number (N) of the tool holder to be replaced becomes 7, and the number (N-1) that is one less becomes 6. The first sensor unit senses whether the first jaw unit rotates 6 times at the basic speed (75Hz, V1) through the first sensing interval of the first jaw unit.

[0109] The first sensor unit counts whether the first claw unit rotates at the basic speed by a number (N-1) less than the number (N) of the tool holder to be replaced. When the counting result shows that the first claw unit has rotated by a number (N-1) less than the number (N) of the tool holder to be replaced, the motor is decelerated to the primary deceleration speed (V2), and at the same time, the second sensor unit is activated so that the second sensor unit senses the rotation of the second claw unit. That is, when the control unit sends a signal to decelerate to the primary deceleration speed to the inverter unit, the current applied to the motor from the inverter unit becomes 10 Hz, and the motor rotates at the primary deceleration speed.

[0110] Specifically, for example, when the first sensor unit counts that the first claw unit has rotated 6 times, the second sensor unit is activated by a signal. When 80ms has passed since the second sensor unit was activated, a signal is sent to the inverter unit to reduce the rotation speed of the motor to 10Hz, which is the first-level reduction speed.

[0111] When the second sensor unit is activated to sense the rotation of the second claw unit, the counting result of the first sensor unit is that when the first claw unit performs the last rotation (N rotations) of the number (N) of the tool magazine to be replaced at the first-level deceleration speed, the control unit sends a signal to decelerate the motor to the second-level deceleration speed at the moment the first sensing interval enters the first sensor unit, thereby, the current applied from the inverter unit to the motor is changed to 3Hz, the motor rotates at the second-level deceleration speed, and the camshaft of the rotating unit rotates at the second-level deceleration speed, thereby, the first claw unit and the second claw unit rotate at the second-level deceleration speed.

[0112] That is, after the first claw unit rotates 6 times, it rotates at 10Hz for 15ms, and then the motor is changed to a 2nd-stage deceleration speed of 3Hz and rotates for 30ms. In this way, the first claw unit performs the counting claw and deceleration claw functions at the same time.

[0113] Afterwards, the control unit recognizes that the replacement tool holder is in the correct position when the motor rotates slowly at a secondary deceleration speed slower than the primary deceleration speed according to the number (N) of the first claw unit at the last rotation, and the second sensor unit senses the second sensing interval whose circumference is smaller than the first sensing interval. That is, the second sensing interval is formed to be much smaller than the first sensing interval, and the last circle rotates slowly, so that the second sensor unit quickly and accurately senses the rotation of the second claw unit, and the replacement tool holder is correctly located at the replacement position. In this way, the second claw unit performs the function of correctly positioning the claw to confirm the position.

[0114] Afterwards, when the control unit completes the correct positioning according to the signal of the second sensor unit, a control signal is sent to the inverter unit to stop the motor, and the DC braking of the inverter unit is started to stop the rotation of the tool magazine.

[0115] That is, when the T8 replacement tool holder rotates a total of 7 turns and moves 7 tool holders counterclockwise to the correct tool replacement position, the DC braking of the inverter unit is maintained for 2000ms through the signal of the control unit to prevent the rotation of the tool magazine.

[0116] After that, since it is difficult to maintain the DC braking of the inverter unit, the DC braking is released after a predetermined time has passed, and the tool replacement is performed in a state where the motor brake is activated to prevent the rotation of the tool magazine drum.

[0117] That is, after 500ms from the start of the inverter unit DC braking, the motor brake is activated to prevent the tool magazine drum from rotating, and the tool is replaced according to the tool replacement signal.

[0118] Reference Fig. 9 , a control method for an automatic tool changing device of a machine tool according to the present invention will be described. Fig. 9 As shown, the control method of the automatic tool changing device of a machine tool according to the present invention includes: a data storage step (S1), a tool changing instruction generation step (S2), an N-1 rotation number calculation step (S3), a motor brake release step (S4), a basic speed rotation step (S5), a rotation number counting step (S6), a primary deceleration step (S7), an activation step (S8), a secondary deceleration step (S9), a positioning step (S10), a DC braking operation step (S11), a motor brake operation step (S12), and a tool changing step (S13). The specific operation process, working principle, structure or content of the device in each step is the same as the automatic tool changing device of a machine tool in the specification of the present invention. Fig. 9 The peculiarities of the control method of the automatic tool changing device of the machine tool will be described in detail.

[0119] As described above, according to the automatic tool change control method of the machine tool of the present invention, basically, the tool holder of the tool magazine moves one cutting edge to perform tool change every time the rotary unit rotates one circle.

[0120] When a tool change instruction is generated, the number of rotations of the first claw unit from the first sensor unit and the correct position of the second claw unit from the second sensor unit are confirmed, and the current applied from the inverter unit to the motor of the drive unit is adjusted to change the rotation speed of the drive unit into multiple levels. At the same time, data of the rotating unit for performing tool change is stored.

[0121] After the data storage step, a tool changing instruction for changing the tool in the tool magazine is generated according to the machining process through the machining program and the tool changing program.

[0122] After the tool replacement command generation step (S2), the control unit calculates the number of rotations (N-1) which is one less than the number (N) of the tool holder to be replaced based on the generated tool replacement command.

[0123] After the step (S3) of calculating the number of rotations (N-1) which is one less than the number (N) of the tool holder to be replaced, the control unit releases the motor brake, thereby allowing the motor to be driven to rotate according to the current signal of the inverter.

[0124] After the motor brake releasing step (S4), the motor is started at a basic speed to rotate the drive unit at the basic speed.

[0125] After the basic speed rotating step (S5), the first sensor unit senses whether the first claw unit counts the number of rotations after rotating.

[0126] After the rotation number counting step (S6), when the counting result shows that the first jaw unit has completed one rotation less than the number of the tool holder to be replaced, the motor is decelerated to the first deceleration speed and the rotating unit is decelerated to the first deceleration speed.

[0127] After the primary deceleration step (S7), the second sensor unit is activated so that the second sensor unit senses the rotation of the second claw unit.

[0128] After the activation step (S8), the counting result shows that when the first jaw unit performs the last rotation of the number of the tool holder to be replaced at the first deceleration speed, the motor is decelerated to the second deceleration speed at the moment when the first sensing interval of the first jaw unit enters the first sensor unit.

[0129] After the secondary deceleration step (S9), if the second sensor unit senses the second sensing interval of the second claw unit, the motor is stopped so that the tool holder to be replaced is located at the correct position.

[0130] After the positioning step (S10), the DC braking of the inverter unit is started to stop the rotation of the tool magazine.

[0131] After the DC braking operation step (S11), in a state where the DC braking of the inverter unit is operated, after a predetermined time has passed, the DC braking of the inverter unit is released to activate the motor brake.

[0132] After the motor brake operation step (S12), tool replacement is performed according to the tool replacement command.

[0133] Thus, according to the automatic tool changing device of a machine tool and the control method thereof of the present invention, according to the generated tool changing instruction, the first jaw unit is rotated at a basic speed by a number less than the number of the tool holder to be replaced, and when the counting result shows that the first jaw unit has rotated by a number less than the number of the tool holder to be replaced, the motor is decelerated to a primary deceleration speed and the second sensor unit for sensing the rotation of the second jaw unit is activated. Then, according to the counting result, when the first jaw unit makes the final rotation of the number of the tool holder to be replaced at the primary deceleration speed, the motor is decelerated to a secondary deceleration speed at the moment it enters the first sensing interval into the first sensor unit, and when the second sensor unit senses the second sensing interval , recognize that the tool holder to be replaced is in the correct position, stop the motor, and then start the DC braking of the inverter to stop the tool magazine from rotating. After a predetermined time, the DC braking is released, and the motor brake is started to perform tool replacement. Thus, according to the counted number of rotations of the claw unit, the rotation speed of the claw unit is changed to multiple levels. Therefore, even if a gear motor is used, the tool can be automatically replaced without stopping when one of the blades of the tool holder is moved. Therefore, the tool change time and non-machining time can be reduced, the machining cost can be saved, the productivity can be improved, the vibration can be prevented, the machining accuracy can be improved, the stability and reliability of the machine tool can be improved, and since a servo motor is not used, the manufacturing cost can be saved and the customer satisfaction can be improved.

[0134] In the detailed description of the present invention described above, the preferred embodiments of the present invention are described with reference to them, but it should be understood that as long as a skilled person in the field to which the present invention belongs or a skilled person with common knowledge in the field to which the present invention belongs, the present invention can be variously modified and changed within the scope of the idea and technical field of the present invention recorded in the scope of the claims. Therefore, the technical scope of the present invention is not limited to the contents recorded in the detailed description of the specification, but is determined by the scope of the claims.

[0135] Explanation of symbols

[0136] 1: Automatic tool changing device, 10: Tool magazine, 20: Drive unit, 30: Rotation unit, 40: Claw unit, 50: Sensor unit, 60: Inverter unit, 70: Control unit.

Claims

1. An automatic tool changing device for a machine tool, characterized in that: include: The tool magazine has multiple tool pockets and is rotatably arranged; A driving unit, used to generate a rotational power for the tool magazine; A rotating unit, which is linked with the rotation of the driving unit to rotate the tool magazine; A claw unit is mounted on the rotating unit and rotates along with the rotation of the rotating unit; a sensor unit disposed adjacent to the claw unit and sensing the claw unit; an inverter unit for driving the driving unit by applying a current to the driving unit; as well as Control unit for controlling tool change, When a tool change instruction is generated, the control unit confirms the number of rotations and the correct position of the claw unit counted from the sensor unit, and adjusts the hertz applied to the drive unit from the inverter unit, thereby changing the rotation speed of the drive unit in multiple stages while rotating the tool magazine to perform tool change.

2. The automatic tool changing device for a machine tool according to claim 1, characterized in that: In the automatic tool changing device, the tool sleeve moves one cutting edge each time the rotating unit rotates one circle. Regardless of the type of the motor of the driving unit, when a tool holder for tool replacement is designated according to the tool replacement instruction, the rotating unit continuously rotates until the replacement target tool holder moves to the tool replacement position.

3. The automatic tool changing device for a machine tool according to claim 2, characterized in that: The claw unit comprises: a first claw unit having a first sensing area protruding in a circumferential direction and mounted on the rotating unit to rotate with the rotation of the rotating unit; and The second claw unit has a second sensing area protruding in the circumferential direction, is arranged on the rotating unit in sequence with the first claw unit, and rotates in conjunction with the first claw unit.

4. The automatic tool changing device for a machine tool according to claim 3, characterized in that: The sensor unit comprises: a first sensor unit disposed adjacent to the first claw unit to sense the first claw unit through the first sensing section when the first claw unit rotates; and The second sensor unit is disposed adjacent to the second claw unit to sense the second claw unit through the second sensing area when the second claw unit rotates.

5. The automatic tool changing device for a machine tool according to claim 4, characterized in that: The circumference of the first sensing section is formed to be larger than the circumference of the second sensing section.

6. The automatic tool changing device for a machine tool according to claim 5, characterized in that: The control unit senses and counts, through the first sensor unit, whether the first claw unit rotates at a basic speed according to the tool replacement instruction generated by one less than the number of the tool holder to be replaced. According to the counting result, when the first claw unit has rotated a number less than the number of the tool sleeve to be replaced, the motor is decelerated to the first deceleration speed, and at the same time, the second sensor unit is activated so that the second sensor unit senses the rotation of the second claw unit.

7. The automatic tool changing device for a machine tool according to claim 6, characterized in that: According to the counting result, when the first claw unit performs the last rotation of the number of the tool holder to be replaced at the first deceleration speed, the control unit decelerates the motor to the second deceleration speed at the moment when the first sensing interval enters the first sensor unit. When the second sensor unit senses the second sensing interval, it recognizes that the tool holder to be replaced is in the correct position, stops the motor, operates the DC braking of the inverter unit, and makes the tool magazine stop rotating. After a predetermined time, the DC braking is released and the motor brake is started.

8. The automatic tool changing device for a machine tool according to claim 7, characterized in that: When generating a tool replacement command, the control unit releases the motor brake and rotates the motor at a basic speed before the first sensor unit senses the rotation of the first jaw unit.

9. The automatic tool changing device for a machine tool according to claim 7, characterized in that: The primary deceleration speed is a speed slower than the basic speed, and the secondary deceleration speed is a speed slower than the primary deceleration speed.

10. The automatic tool changing device for a machine tool according to claim 2, characterized in that: The tool magazine comprises: Base portion; a drum rotatably disposed on the base portion; and A plurality of knife sleeves are arranged at predetermined intervals along the circumferential direction of the drum and are used to accommodate knives.

11. The automatic tool changing device for a machine tool according to claim 10, characterized in that: The driving unit comprises: a motor, disposed on the base portion and activated by the current applied by the inverter unit; a rotating shaft inserted into and coupled to the motor and rotating as the motor rotates; a motor brake provided on the motor to prevent rotation of the motor under control of the control unit; and The transmission unit is arranged on one side of the rotating shaft to transmit the rotating force.

12. The automatic tool changing device for a machine tool according to claim 11, characterized in that: The rotating unit comprises: A cam shaft is rotatably arranged on the base portion and parallel to the rotation axis; A cylindrical cam formed in a spiral shape in the circumferential direction without a horizontal section in the axial direction of the cam shaft; as well as The connecting portion is arranged at one side of the camshaft, is connected with the transmission unit through gear meshing, and rotates along with the rotation of the rotating shaft.

13. The automatic tool changing device for a machine tool according to claim 11, characterized in that: The motor is a gear motor.

14. A control method for an automatic tool changing device of a machine tool, wherein when a rotating unit rotates one circle, a tool holder of a tool magazine moves one cutting edge to perform tool change, characterized in that: include: When a tool change command is generated, the step of confirming the number of rotations of the first jaw unit from the first sensor unit and the correct position of the second jaw unit from the second sensor unit, and adjusting the current applied from the inverter unit to the motor of the drive unit to change the rotation speed of the drive unit into multiple stages, and at the same time, storing data of the rotation unit for executing tool change; The step of generating a tool change instruction for changing a tool of the tool magazine; A step of calculating a number of rotations which is one less than a number of a tool holder to be replaced according to the generated tool replacement command; Steps to release the motor brake; the step of operating the motor at a base speed to rotate the drive unit; the first sensor unit sensing whether the first claw unit is rotating to count the number of rotations; When the counting result shows that the first claw unit has completed a number of rotations less than the number of the tool holder to be replaced, the motor is decelerated to a first-stage deceleration speed, and the rotating unit is decelerated to a first-stage deceleration speed; a step of activating the second sensor unit so that the second sensor unit senses rotation of the second claw unit; According to the counting result, when the first jaw unit performs the last rotation of the number of the tool holder to be replaced at the first deceleration speed, the first sensing interval of the first jaw unit decelerates the motor to the second deceleration speed at the moment of entering the first sensor unit; If the second sensor unit senses the second sensing section of the second claw unit, the motor is stopped to place the tool holder to be replaced in a correct position; The step of operating the DC brake of the inverter unit to stop the rotation of the tool magazine; as well as The step of executing tool change according to the tool change command.

15. The control method of the automatic tool changing device of a machine tool according to claim 14, characterized in that: After the step of operating the DC braking of the inverter unit to stop the rotation of the tool magazine, the method further includes: while the DC braking of the inverter unit is being operated, releasing the DC braking of the inverter unit after a predetermined time has passed, and starting the motor brake.

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