KR102116581B1 - Method and Apparatus for Clamping and Unclamping Workpiece Using Servo Motor - Google Patents

Abstract

The present invention relates to a method and apparatus for clamping and unclamping a work piece using a servo motor, and is connected to a draw bar to move the draw bar forward and backward to operate a chuck; An encoder unit for detecting the position of the servo motor; A drive unit controlling a current flowing through the servo motor to control the position of the server motor; A brake unit fixing or releasing the shaft of the servo motor; A thrust holding unit that maintains thrust of the servo motor; And a thrust value and a position value, and while detecting the position of the servo motor using the encoder unit, controls the servo motor to be located at the input position value through the drive unit, and receives the servo motor from the drive unit. It includes a control unit for fixing the shaft of the servo motor through the brake unit, when the load value of reaches the input thrust value.

Description

Method and Apparatus for Clamping and Unclamping Workpiece Using Servo Motor}

The present invention relates to a method and apparatus for clamping and unclamping a workpiece using a servo motor instead of conventionally clamping and unclamping the workpiece using hydraulic or pneumatic components.

In general, lathes are known as cutting automation devices that freely perform 3D machining by inputting data while the workpiece is gripped by the chuck.

Lathes can be easily and quickly processed even in the form of complex curved workpieces with high precision that cannot be imagined in conventional handle-operated machine tools, and are not affected by the operator's mood and fatigue, and mistakes caused by operator error Because there are few, there are few defects in the workpiece. In addition, the lathe has an advantage of uniform precision, good symmetry, high repetition precision, and excellent work uniformity, making it easy to assemble, while cutting speed and depth of cut can all be selected in advance to a suitable value. And the advantage of being able to achieve the optimum of the finished surface.

1 is a cross-sectional view showing a conventional workpiece clamping and unclamping device.

Referring to FIG. 1, a conventional workpiece clamping and unclamping device includes a cylinder block 110, a spindle 120, a chuck 130, a draw bar 140, a moving bar 150, and the like.

The cylinder block 110 is provided with a hydraulic pressure supply unit 115 through which hydraulic pressure is supplied, and a cylinder portion 116 through which a piston 111 reciprocating by hydraulic pressure supplied from the hydraulic pressure supply unit 115 is installed in the inner space 116a. Is done. The hydraulic supply unit 115 is provided with a pair of hydraulic holes (not shown) for selectively supplying hydraulic pressure to any one of both sides of the piston 111 to control the reciprocating motion of the piston 111.

In addition, the spindle 120 is rotatably installed inside the main shaft body (not shown) installed on one side of the cylinder block 110.

In addition, the chuck 130 is disposed on one side of the spindle 120 and has a jaw that can clamp or unclamp a work piece (not shown).

The draw bar 140 is disposed inside the spindle 120 and connects the cylinder portion 116 and the chuck 130 to move forward and backward by hydraulic pressure supplied to the interior of the cylinder portion 116, and thus the chuck 130 ) Is activated (clamping and unclamping).

In addition, the moving bar 150 is integrally connected to the piston 111 and reciprocally movable together with the piston 111, and one end is coupled to the draw bar 140 to connect the draw bar 140 forward and backward. do.

However, the conventional workpiece clamping and unclamping apparatus can maintain only a constant pressure because the piston 111 is operated by hydraulic pressure, and thus it is quite difficult to drive equipment for various types of workpieces. That is, when various workpieces are drawn in, the operator has to change the set value one by one while looking at the hydraulic gauge every time.

In addition, additional hardware devices, such as a chuck confirmation switch, were required to confirm that the workpiece was well-fed, and the device also provided fairly inaccurate information.

In addition, it was virtually impossible to change the pressure in the existing chuck 130, and there was a problem in that the workpiece may be damaged when the workpiece becomes lighter or the jaw grip surface becomes thinner.

This specification has been devised to solve the problems as described above, and the servo motor that can prevent the distortion of the material from excessive pressure by automatically changing the pressure for clamping the workpiece according to the type, weight and cutting process of the workpiece. An object of the present invention is to provide a method and apparatus for clamping and unclamping a work piece using a metal.

Another object of the present specification is to provide a method and apparatus for clamping and unclamping a work piece using a servo motor that can prevent a risk that may occur due to low pressure.

Another object of the present specification is to provide a method and apparatus for clamping and unclamping a workpiece using a servo motor capable of measuring the state of holding the workpiece in real time.

In order to achieve the above object, according to the first embodiment of the present specification, a workpiece clamping and unclamping apparatus using a servo motor according to the present specification is a spindle rotatably installed inside a main body, one side of the spindle A workpiece clamping and unclamping device comprising a chuck having a jaw disposed on the workpiece and having a jaw capable of clamping or unclamping a workpiece, and a drawbar disposed inside the spindle to operate the chuck, connected to the drawbar, A servo motor that moves the bar forward and backward to operate the chuck; An encoder unit for detecting the position of the servo motor; A drive unit controlling a current flowing through the servo motor to control the position of the server motor; A brake unit fixing or releasing the shaft of the servo motor; A thrust holding unit that maintains thrust of the servo motor; And a thrust value and a position value, and while detecting the position of the servo motor using the encoder unit, controls the servo motor to be located at the input position value through the drive unit, and receives the servo motor from the drive unit. It includes a control unit for fixing the shaft of the servo motor through the brake unit, when the load value of reaches the input thrust value.

Preferably, when the jaw is gradually tightened as the servo motor advances, and when the jaw comes into contact with the end face of the workpiece, the servo motor reaches a state where it cannot move beyond the compression amount of the thrust holding portion, and the The thrust of the servo motor increases, and the thrust holding unit stores the same thrust as the servo motor.

Preferably, the thrust holding unit maintains thrust of the servo motor through stored thrust when the thrust value of the servo motor reaches an input thrust value and the shaft of the servo motor is fixed by the brake unit. Is done.

Preferably, the thrust holding portion is characterized in that the spring.

According to a first embodiment of the present specification, a method of clamping and unclamping a work piece using a servo motor according to the present specification includes: receiving a thrust value and a position value; If there is a clamping or unclamping command, driving a servo motor for a clamping or unclamping operation; Receiving a load value of the servo motor; Determining whether the position of the servo motor is the same as the input position value, and whether the load value of the servo motor is the same as the input thrust value; And fixing the shaft of the servo motor when the position of the servo motor is the same as the input position value and the load value of the servo motor is the same as the input thrust value.

Preferably, in the step of fixing the shaft of the servo motor, the thrust of the servo motor is maintained through the stored thrust.

As described above, according to the present specification, by providing a method and apparatus for clamping and unclamping a work piece using a servo motor that automatically sets the chuck's feed position and thrust, the position and thrust control according to machining at a specified position are controlled. It is possible to maintain a certain processing quality by preventing distortion, and it is possible to reduce the waiting time for processing by varying the thrust in processing various materials.

1 is a cross-sectional view showing a conventional workpiece clamping and unclamping device,
Figure 2 is a cross-sectional view showing a workpiece clamping and unclamping apparatus using a servo motor according to an embodiment of the present invention,
3 is a flowchart illustrating a method of clamping and unclamping a workpiece using a servo motor according to an embodiment of the present invention.

It should be noted that the technical terms used in this specification are only used to describe specific embodiments and are not intended to limit the present invention. In addition, technical terms used in this specification should be interpreted as meanings generally understood by those having ordinary knowledge in the technical field to which the present invention belongs, unless defined otherwise. It should not be interpreted as a meaning or an excessively reduced meaning. In addition, when the technical term used in this specification is a wrong technical term that does not accurately represent the spirit of the present invention, it should be understood as being replaced by a technical term that can be correctly understood by those skilled in the art. In addition, the general terms used in the present invention should be interpreted as defined in the dictionary or in context before and after, and should not be interpreted as an excessively reduced meaning.

In addition, the singular expression used in this specification includes the plural expression unless the context clearly indicates otherwise. In the present application, the terms "consisting of" or "comprising" should not be construed as including the various components, or various steps described in the specification, among which some components or some steps It may not be included, or it should be construed to further include additional components or steps.

In addition, the suffixes "module" and "part" for the components used in the present specification are given or mixed only by considering the ease of writing the specification, and do not have a meaning or a role distinguished from each other in itself.

Further, terms including ordinal numbers such as first and second used in the present specification may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from other components. For example, the first component may be referred to as a second component without departing from the scope of the present invention, and similarly, the second component may also be referred to as a first component.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings, but the same or similar elements will be given the same reference numbers regardless of the reference numerals, and redundant descriptions thereof will be omitted.

In addition, in the description of the present invention, when it is determined that detailed descriptions of related known technologies may obscure the subject matter of the present invention, detailed descriptions thereof will be omitted. In addition, it should be noted that the accompanying drawings are only for easy understanding of the spirit of the present invention and should not be interpreted as limiting the spirit of the present invention by the accompanying drawings.

2 is a cross-sectional view showing a workpiece clamping and unclamping apparatus using a servo motor according to an embodiment of the present invention.

Referring to Figure 2, since the workpiece clamping and unclamping apparatus using a servo motor according to the present invention clamps and unclamps a workpiece using a servo motor, the cylinder block 110 in the workpiece clamping and unclamping apparatus of FIG. Does not need.

That is, the workpiece clamping and unclamping device using the servo motor according to the present invention includes a spindle 210, a chuck 220, a draw bar 230, a servo motor 240, an encoder unit 250, a drive unit 260 , A brake unit 270, a thrust holding unit 280, an operation unit 290 and a control unit 300.

Since the functions of the spindle 210, the chuck 220, and the drawbar 230 of the workpiece clamping and unclamping apparatus using a servo motor according to an embodiment of the present invention are the same as the workpiece clamping and unclamping apparatus of FIG. 1, Description of this will be omitted.

The servo motor 240 is connected to the draw bar 230 to operate (clamp and unclamp) the chuck 220 by moving the draw bar 230 forward and backward.

The encoder unit 250 detects the rotational speed and position of the servo motor 240. Here, the encoder unit 250 may be an incremental position detection encoder or the like.

The drive unit 260 controls the current flowing through the servo motor 240 under the control of the control unit 300 to control the rotational speed and position of the servo motor 240. Also, the drive unit 260 may transmit the current value of the servo motor 240, that is, the load value to the control unit 300. Here, the drive unit 260 may be an amplifier or the like.

The brake unit 270 fixes or releases the shaft of the servo motor 240.

The thrust holding unit 280 maintains the thrust of the servo motor 240. In detail, the thrust holding unit 280 stores the thrust of the servo motor 240 as the thrust of the servo motor 240 rises, and the thrust value of the servo motor 240 reaches the input thrust value and the brake unit ( When the shaft of the servo motor 300 is fixed by 290, the thrust of the servo motor 240 is maintained through the stored thrust. To this end, the thrust holding unit 280 may be a spring or the like. Here, the thrust holding unit 280 is preferably located between the servo motor 240 and the spindle 210, as shown in FIG.

The manipulation unit 290 instructs the control unit 300 to clamp or unclamp the workpiece, and receives thrust values and position values of the servo motor 240 from the operator. In addition, the operation unit 290 may include an automatic operation unit (not shown) for automatic operation and a manual unit (not shown) for manual operation. Here, the operation unit 290 may be implemented as a liquid crystal display (LCD), a light emitting diode (LED), an organic light emitting diode (OLED), a plasma display device (PDP), a touch panel and a touch pad.

The control unit 300 receives the thrust value and the position value through the operation unit 290, and detects the position of the servo motor 240 using the encoder unit 250, while the servo motor 240 through the drive unit 260 ) Is controlled to be located at the input position value, and when the load value of the servo motor 240 received from the drive unit 260 reaches the input thrust value, the servo motor 240 through the brake unit 270 Fix the shaft.

Hereinafter, the operation of the clamping and unclamping of a workpiece using a servo motor according to an embodiment of the present invention will be described.

First, the thrust value and the position value of the servo motor 240 are input from the operator.

Then, the jaw 222 is gradually tightened as the servo motor 240 located behind the spindle 210 advances according to the clamping command of the operator.

When the jaw 222 comes into contact with the end face of the workpiece, the servo motor 240 reaches a state where it cannot move beyond the compression amount of the thrust holding unit 280, and accordingly the thrust of the servo motor 240 rises. The thrust holding unit 280 stores the same thrust as the servo motor 240 (at this time, the thrust holding unit 280 is compressed).

Then, when the thrust of the servo motor 240 reaches the input thrust value, the brake unit 270 fixes the shaft of the servo motor 240, and the jaw is driven by the thrust stored in the thrust holding unit 280 (222). ) Clamps the workpiece.

As described above, in the workpiece clamping and unclamping apparatus using the servo motor according to the present invention, the servo motor 240 does not provide all thrust for clamping the workpiece, for example, the servo motor 240 is 80% Provides thrust, and thrust holding unit 280 provides 20% thrust.

Therefore, the workpiece clamping and unclamping apparatus using the servo motor according to the present invention performs a clamping operation by using the elasticity of the thrust holding unit 280, so that the material from the excessive pressure can be prevented from being crushed. Low can prevent possible risks.

3 is a flowchart illustrating a method of clamping and unclamping a workpiece using a servo motor according to an embodiment of the present invention.

Referring to FIG. 3, the workpiece clamping and unclamping apparatus using the servo motor according to the present invention maintains a standby state (S300) and determines whether there is a request for setting thrust values and position values (S302).

When there is a request to set the thrust value and the position value, a setting screen for inputting the thrust value and the position value is provided (S304).

The thrust value and the position value are received through the setting screen (S306), and the received thrust value and position value are stored (S308).

Then, the workpiece clamping and unclamping apparatus using the servo motor determines whether there is a clamping or unclamping command (S310).

When there is a clamping or unclamping command, the servo motor 260 is driven for a clamping or unclamping operation (S312).

The load value of the servo motor 260 is received from the drive unit 260 (S314).

Subsequently, it is determined whether the position of the servo motor 260 is the same as the input position value, and whether the load value of the servo motor 260 is the same as the input thrust value (S316).

When the position of the servo motor 260 is the same as the input position value, and the load value of the servo motor 260 is the same as the input thrust value, the shaft of the servo motor 240 is fixed using the brake unit 270. Let (S318). At this time, the jaw 222 clamps the workpiece by the thrust stored in the thrust holding unit 280.

Thereafter, the result of clamping or unclamping is displayed on the setting screen (S320). At this time, when the clamping or unclamping is normally completed, a message indicating that the clamping or unclamping is normally completed is displayed to inform the operator that the chuck 220 is clamping the work piece with the input thrust value, and the clamping or unclamping is abnormal. When this is completed, an abnormally clamping or unclamping message may be displayed.

The above-described method can be implemented through various means. For example, embodiments of the present invention may be implemented by hardware, firmware, software, or a combination thereof.

For implementation by hardware, the method according to embodiments of the present invention includes one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs) , Field Programmable Gate Arrays (FPGAs), processors, controllers, microcontrollers, and microprocessors.

In the case of implementation by firmware or software, the method according to embodiments of the present invention may be implemented in the form of a module, procedure, or function that performs the functions or operations described above. The software code can be stored in a memory unit and driven by a processor. The memory unit is located inside or outside the processor, and can exchange data with the processor by various known means.

The embodiments disclosed herein have been described above with reference to the accompanying drawings. As described above, the embodiments illustrated in each drawing should not be interpreted as being limited, and may be combined with each other by those skilled in the art who understand the contents of the present specification, and when combined, some components may be omitted.

Here, the terms or words used in the specification and claims should not be interpreted as being limited to ordinary or dictionary meanings, but should be interpreted as meanings and concepts corresponding to the technical ideas disclosed in this specification.

Therefore, the configuration shown in the embodiments and the drawings described in this specification is only an embodiment disclosed in the present specification, and does not represent all of the technical ideas disclosed in the specification, and thus can replace them at the time of application. It should be understood that there may be equivalents and variations.

210: spindle 220: chuck
222: Jaw 230: Drawbar
240: servo motor 250: encoder unit
260: drive unit 270: brake unit
280: thrust holding unit 290: operation unit
300: control unit

Claims (6)

A work piece including a spindle rotatably installed inside the headstock body, a chuck disposed on one side of the spindle and having a jaw capable of clamping or unclamping the work piece, and a draw bar disposed inside the spindle to operate the chuck. In the clamping and unclamping device,
A servo motor connected to the drawbar to operate the chuck by moving the drawbar forward and backward;
An encoder unit for detecting the position of the servo motor;
A drive unit controlling a current flowing through the servo motor to control the position of the servo motor;
A brake unit fixing or releasing the shaft of the servo motor;
A thrust holding unit that maintains thrust of the servo motor; And
While receiving the thrust value and the position value, and detecting the position of the servo motor using the encoder unit, the servo motor is controlled to be positioned at the input position value through the drive unit, and the servo motor received from the drive unit A control unit for fixing the shaft of the servo motor through the brake unit when the load value reaches the input thrust value;
Including,
When the jaw is gradually tightened as the servo motor advances, and the jaw comes into contact with the end face of the workpiece, the servo motor reaches a state where it cannot move beyond the compression amount of the thrust holding portion, and the thrust of the servo motor As this rises, the same thrust as the servo motor is stored in the thrust holding unit,
The thrust holding unit maintains thrust of the servo motor through stored thrust when the thrust value of the servo motor reaches an input thrust value and the shaft of the servo motor is fixed by the brake unit. Clamping and unclamping device using a tool. delete delete According to claim 1,
The thrust holding portion is a clamping and unclamping device using a servo motor, characterized in that the spring. Receiving a thrust value and a position value;
If there is a clamping or unclamping command, driving a servo motor for a clamping or unclamping operation;
Receiving a load value of the servo motor;
Determining whether the position of the servo motor is the same as the input position value, and whether the load value of the servo motor is the same as the input thrust value; And
Fixing the shaft of the servo motor when the position of the servo motor is the same as the input position value and the load value of the servo motor is the same as the input thrust value;
Including,
When the jaw capable of clamping the workpiece gradually tightens as the servo motor advances, and when the jaw comes into contact with the end face of the workpiece, the servo motor will move beyond the compression amount of the thrust holding portion that maintains the thrust of the servo motor. When the thrust of the servo motor rises, the same thrust as that of the servo motor is stored in the thrust holding unit.
The thrust holding unit maintains the thrust of the servo motor through the stored thrust when the shaft of the servo motor is fixed by the brake unit fixing the shaft of the servo motor by reaching the thrust value at which the thrust of the servo motor is input. Clamping and unclamping method using a servo motor, characterized in that. delete

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