KR20090060518A - Apparatus for automatically returning reference point of machine tool and method thereof - Google Patents

Abstract

A device for automatically returning a home position of a machine tool and a method thereof are provided to detect a dog for sensing the home position to return the home position if an operator orders the return to the home position. A device for automatically returning a home position of a machine tool comprises: an Z-axis transfer servo motor(10) operating a screw(80) to the clockwise direction or the counter-clockwise direction; an Z-axis head(20) going up and down relative to the rotation of the Z-axis transfer servo motor; a dog(30) for sensing the home position to limit home position of the Z-axis head; a top limit dog(40) sensing the Z-axis head positioned in the top when being contacted with the Z-axis head; a bottom limit dog(50) sensing the Z-axis head positioned in the bottom when being contacted with the Z-axis head; and a home position approaching switch(60) for sensing the home position to detect the present location of the Z-axis head by sensing the top and bottom limit dog.

Description

Automatic zero point return device and method for machine tools {APPARATUS FOR AUTOMATICALLY RETURNING REFERENCE POINT OF MACHINE TOOL AND METHOD THEREOF}

The present invention relates to an automatic home position return device and method for a machine tool, in particular, having a home position detection dog, an upper limit dog and a lower limit dog, by returning to the home position by touching the dog to return to the home position and At the same time, the present invention relates to an automatic homing apparatus and method for machine tools, characterized in that to increase the homing speed of the machine tool.

1 is a view for explaining a home position return method of a conventional machine tool, the machine tool as shown in the servo motor (1) and the rotary shaft (2) including an encoder for generating a zero return signal of the motor as shown largely; , The machine tool 4, and the servo shaft 1 rotates clockwise (CW) or counterclockwise (CCW) so that the rotary shaft 2 interlocks and reaches a desired position. Straighten the machine tool (4).

The encoder generates one home pulse, i.e., Z phase pulse, every time the servo motor 1 rotates, and based on this home pulse, the absolute position of the servo motor 1, i.e., the home position P by the servo motor. ) Is determined. This is calculated in consideration of the feeding distance per one revolution (360 degrees) of the servomotor 10.

After finding the origin A of the servomotor 1, the origin return is completed by actually moving the machine tool 4 to the origin O of the machine by a predetermined displacement X for the origin return.

However, in the prior art as described above, since the operator selects each axis and then manually presses a button to return to the origin, the operation is inconvenient according to the manual operation of each axis. Another problem is that it can cause a crash.

In addition, if the work through the servo motor is continuously progressed, it is difficult to calculate the distance between the origin and the current servo motor, so the operator has to move the servo motor to the origin manually, resulting in poor workability.

An object of the present invention is to solve the above problems, by installing the upper limit dog and the lower limit dog of the upper and lower portions of the origin detection dog 30 and the origin detection dog 30 by various dogs The purpose is to calculate the location area so that you can quickly return to the origin.

As a means for achieving the above object, the present invention includes a Z-axis feed servomotor 10 for driving the screw 80 installed on the bed 70 of the machine tool in a clockwise or counterclockwise direction; Z-axis feed servo motor coupled to the screw to move up and down, the Z-axis head (20) to the upper or lower down the screw according to the rotation in the clockwise or counterclockwise direction; Is installed at one end of the bed 70, the origin detection dog 30, which is a sensing dog for defining the origin of the Z-axis head; The sensing dog is installed on the upper part of the bed 70, but is located on the top of the origin detecting dog 30, and the Z-axis head 20 is located on the upper part when the Z-axis head 20 touches. An upper limit dog 40; The sensing dog is installed at the bottom of the bed 70, but is located at the bottom of the origin detecting dog 30, and the Z-axis head 20 is located at the bottom when the Z-axis head 20 touches. A phosphorus lower limit dog 50; It is installed below the Z-axis head 20 and senses the current position of the Z-axis head 20 by sensing the origin detection dog 30, the upper limit dog 40 and the lower limit dog 50. It characterized in that it comprises a proximity switch for detecting the origin (60).

In addition, the present invention, in order to return to the machine tool origin, first, when the operator gives a command to return to the home position, preparing a transfer of the Z-axis head; When the Z axis head is located between the origin detection dog 30 and the upper limit dog based on the origin detection dog 30, the Z axis head is lowered to sense the origin detection dog 30, and then the predetermined origin position ( O) feeding the Z-axis head; If it is determined that the Z-axis head is located on the origin dog, lowering the Z-axis head to determine the position of the origin detection dog 30 and transferring the Z-axis head to a predetermined origin position (O); When the Z-axis head is positioned between the origin detection dog 30 and the lower limit dog based on the origin detection dog 30, the Z-axis head is raised to sense the origin detection dog 30, and then the predetermined origin position ( It characterized in that it comprises a step of feeding the Z-axis head to O).

The present invention includes an upper limit dog, a lower limit dog, and an origin detecting dog 30 to grasp the position of the Z-axis head so that when the user commands the origin return, the home sensing dog 30 is automatically sensed by sensing the origin detecting dog 30. Return is possible. Therefore, the inconvenience of the conventional home return method of the manual operation method is eliminated and the erroneous operation by the mistake of an operator is prevented beforehand.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

2 is a configuration diagram of the present invention, Figure 3 is a flow chart of the present invention.

First, as shown in FIG. 2, the present invention provides a Z-axis feed servomotor 10, a Z-axis head 20, an origin detecting dog 30, an upper limit dog 40, and a lower limit. It is provided with the dog 50 and the proximity switch 60 for origin detection.

In the embodiment shown in FIG. 2, it is assumed that the position of the origin O is located at an upper portion by a predetermined distance of the origin detection dog 30. However, the position of the origin O may be located below a certain distance of the origin detection dog 30.

In addition, area A means an area above the origin O, or an upper area of the origin detection dog 30, area B means an area on the origin detection dog 30, and area C refers to the origin detection. It refers to the lower region of the dog 30.

The Z-axis feed servomotor 10 is a driving means for driving the screw 80 installed in the bed 70 of the machine tool clockwise or counterclockwise.

The Z-axis head 20 is coupled to the screw 80 to move up and down, the Z-axis feed servomotor 10 is raised to the top or lowered by rotating the screw clockwise or counterclockwise. .

The origin detecting dog 30 is a sensing dog installed at the immediate vicinity of the origin O of the bed 70 to limit the origin of the Z axis head 20.

The upper limit dog 40 is positioned above the origin detecting dog 30 so that when the Z axis head 20 touches the upper limit dog 40, the Z axis head 20 is larger than the origin O. Make sure you are in the upper area.

The lower limit dog 50 is positioned below the origin detection dog 30 so that when the Z axis head 20 touches the lower limit dog 50, the Z axis head 20 is smaller than the origin O. Be aware that you are in the lower area.

The proximity detection proximity switch 60 is installed under the Z axis head 20, and senses the origin detection dog 30, the upper limit dog 40, and the lower limit dog 50 to sense the Z axis head 20. It is possible to determine the current position of the at a high speed, and accordingly to allow the Z-axis head 20 to easily find the origin (O).

That is, in the present invention, the proximity switch 60, that is, the limit sensor, is coupled to the lower portion of the Z-axis head 20, and the origin detection dog 30 is provided near the origin O. The upper and lower limit dogs 30 and 40 are respectively installed at the upper and lower portions of the dog 30, so that the home position sensing proximity switch 60 is provided with the upper limit dog 40, the lower limit dog 50, and the origin sensing dog. By detecting the 30, the Z-axis head 20 can be easily returned to the origin O at any position.

Hereinafter, a method of returning to the origin according to the position of the Z-axis head 20 will be described.

When the Z-axis head 20 is located in the A area

First, the case in which the Z-axis head 20 is in the area A, that is, the case where the Z-axis head 20 is above the origin O will be described.

In this case, since the Z-axis head 20 can be grasped by the origin detecting proximity switch 60 between the origin detecting dog 30 and the upper limit dog 40, the operator gives the origin return command. It moves at a high speed to the bottom where the origin detecting dog 30 is located.

When the home position proximity switch 60 moves downward and touches the home position detection dog 30 to sense (switch from OFF to ON), the Z-axis head 20 moves upward toward the O position set to the home position. Transfer (turn ON again to OFF).

As described above, in the process of returning the Z-axis head 20 located in the area A to the origin O, the proximity detection proximity switch 60 is turned off, on, and off in order.

On the other hand, even when the Z-axis head 20 is located in O, which is the origin region, the same process as the case where the Z-axis head 20 is located in the A region is performed because it is not known whether the position is the actual origin. That is, once the home detection dog 30 is transferred to the lower position where it is located, and then repositioned to the home position (O) located directly above the home detection dog (30).

In fact, since the distance between the origin detecting dog 30 and the origin O is programmed in advance, after sensing the origin detecting dog 30, the Z axis head 20 is moved upward in the upward direction and then the origin ( O) to the position.

When the Z-axis head 20 is located in the B area

Next, when the Z-axis head 20 is in the B region, the home position detecting dog 30 is immediately sensed (on) by the home position detecting proximity switch 60 or the Z-axis head 20 is at the origin. Since it is impossible to recognize whether it exists in the upper part of the sensing dog 30 or in the lower part of the origin detecting dog 30, once the Z-axis head 20 is moved downward and the origin detecting dog 30 is turned off, After passing through the origin detecting dog 30 again, the upper portion is transferred to the upper portion, and the Z axis head 20 is transferred from the origin detecting dog 30 to an origin point O located at an upper portion of the predetermined distance and returned to the origin point O.

As described above, in the process of returning the Z-axis head 20 located in the B region to the origin O, the proximity detection proximity switch 60 is sequentially turned on, off, on, and off.

When the Z-axis head 20 is located in the C area

In addition, when the Z-axis head 20 is in the C region, it is possible to grasp that it is located between the origin detection dog 30 and the lower limit dog 50 during the operation by the proximity detection proximity switch 60. When the operator issues the home return command, the robot moves to the home detection dog 30 at a high speed and then moves the Z-axis head to the O position set to the home position after sensing the home detection dog 30. .

In this way, in the process of returning the Z-axis head 20 located in the C region to the origin O, the proximity switch 60 for the origin detection is sequentially turned off, on, and off.

Hereinafter, the control operation of the present invention will be clearly described through the flowchart of FIG. 3.

In order to return the machine tool to the home position, first, when the operator gives a home position return command, the Z-axis head 20 is prepared to be transferred (S10).

It is necessary to determine the current position of the Z-axis head 20, the Z-axis head 20 between the origin detection dog 30 and the upper limit dog 40 based on the origin detection dog 30. If is located (area A of FIG. 2), the Z-axis head 20 is lowered to sense the origin detection dog 30 and then re-transfer the Z-axis head 20 toward the predetermined home position (O). .

In this case, when the defined origin position O is set to the upper end of the origin detection dog 30 as shown in FIG. 2, the Z-axis head 20 is moved upward by a predetermined distance to the upper end of the origin detection dog 30. It is enough to return to the origin O by moving, and when the predetermined origin position O is set to the lower end of the origin detection dog 30, the Z-axis head 20 is fixed to the lower end of the origin detection dog 30. It is necessary to return to the origin by moving below the distance (S20).

On the other hand, if it is determined that the Z-axis head 20 is located on the origin detecting dog 30 (region B of FIG. 2), the position of the origin detecting dog 30 is lowered by lowering the Z axis head 20. After the determination, the Z-axis head 20 is re-transmitted to the determined origin position (O).

Also in this case, when the defined origin position O is set to the upper end of the origin detection dog 30 as shown in FIG. 2, the Z-axis head 20 is moved upwards to detect the origin dog 30. After going through again, move upwards by a predetermined distance and return to the origin (O). When the determined origin position (O) is set to the lower end of the origin detection dog 30, the Z axis head 20 is detected by the origin. What is necessary is to continuously return to the lower end of the dog 30 and return to origin (O) (S30).

Finally, when the Z axis head is located between the origin detection dog 30 and the lower limit dog 50 based on the origin detection dog 30 (region B in FIG. 2), the Z axis head 20 Raises) and senses the origin detection dog 30 and transfers the Z-axis head 20 to the defined origin position (O).

In this case, as described above, when the origin point O defined as shown in FIG. 2 is set to the upper end of the origin detection dog 30, the Z-axis head 20 is moved to the upper end of the origin detection dog 30. The original point (O) is returned by moving upward by a certain distance. On the other hand, when the predetermined origin position O is set to the lower end of the origin detection dog 30, the Z axis head 20 is moved downwardly by a predetermined distance to the lower end of the origin detection dog 30, and thus the origin point O is Return is completed (S40).

If the current position of the Z-axis head 20 is unclear, if there is a Z-axis head 20 in the area A, if the Z-axis head 20 is raised to sense the upper limit dog 40 Z-axis Since the head 20 is located between the origin detecting dog 30 and the upper limit dog 40, the head 20 may be lowered to sense the origin detecting dog 30.

Similarly, when the Z-axis head 20 is present in the C region, when the Z-axis head 20 is lowered to sense the lower limit dog 50, the Z-axis head 20 moves to the origin detecting dog 30 and the lower limit. Since it can be seen that the dog 50 is located between, the Z-axis head 20 is raised to sense the dog 30 for detecting the origin.

Typically, since the Z-axis head 20 is sensed by touching the upper limit dog 40 and the lower limit dog 50 during the operation, it is possible to determine in which area the Z-axis head 20 is currently located.

According to the above-described process, when the Z-axis head 20 reaches the home detection dog 30 and the proximity detection proximity switch is turned on, the Z-axis head 20 is added to the preset home position O by a predetermined distance. By returning, the zero point return can be completed.

Although specific embodiments of the present invention have been described above, the spirit and scope of the present invention are not limited to the specific embodiments, and various modifications and changes can be made without departing from the spirit of the present invention. Those skilled in the art will understand.

Therefore, since the embodiments described above are provided to completely inform the scope of the invention to those skilled in the art, it should be understood that they are exemplary in all respects and not limited. The invention is only defined by the scope of the claims.

1 is a view for explaining the home position return method of a conventional machine tool.

Figure 2 is a block diagram for the origin return of the machine tool of the present invention.

3 is a flow chart of a machine tool homing method of the present invention.

<Description of the symbols for the main parts of the drawings>

O: Origin 10: Z-axis feed servomotor

20: Z axis head 30: origin detection dog 30

40: upper limit dog 50: lower limit dog

60: proximity switch for home detection 70: bed of machine tool

80: screw

A: Area A (when the Z-axis head is located above the origin detecting dog 30)

B: B area (when the Z-axis head is located on the origin detecting dog 30)

C: C area (when the Z-axis head is located below the origin detecting dog 30)

Claims (2)

A Z-axis feed servomotor 10 for driving the screw 80 installed on the bed 70 of the machine tool in a clockwise or counterclockwise direction; Z-axis feed servo motor coupled to the screw to move up and down, the Z-axis head (20) to the upper or lower down the screw according to the rotation in the clockwise or counterclockwise direction; Is installed at one end of the bed 70, the origin detection dog 30, which is a sensing dog for defining the origin of the Z-axis head; The sensing dog is installed on the upper part of the bed 70, but is located on the top of the origin detecting dog 30, and the Z-axis head 20 is located on the upper part when the Z-axis head 20 touches. An upper limit dog 40; The sensing dog is installed at the bottom of the bed 70, but is located at the bottom of the origin detecting dog 30, and the Z-axis head 20 is located at the bottom when the Z-axis head 20 touches. A phosphorus lower limit dog 50; It is installed below the Z-axis head 20 and senses the current position of the Z-axis head 20 by sensing the origin detection dog 30, the upper limit dog 40 and the lower limit dog 50. Proximity Switch for Origin Detection (60) Automatic home position return device for a machine tool comprising a. When the operator issues a home position return command, preparing a transfer of the Z-axis head (S10); When the Z axis head is located between the origin detection dog 30 and the upper limit dog based on the origin detection dog 30, the Z axis head is lowered to sense the origin detection dog 30, and then the predetermined origin position ( O) feeding the Z-axis head (S20); If it is determined that the Z-axis head is located on the home position detection dog 30, the Z-axis head is lowered to determine the position of the home position detection dog 30, and then transferred to the predetermined home position (O) Z-axis head (S30); When the Z-axis head is positioned between the origin detection dog 30 and the lower limit dog based on the origin detection dog 30, the Z-axis head is raised to sense the origin detection dog 30, and then the predetermined origin position ( O) Z-axis feed to the automatic home return method of the machine tool, characterized in that the step consisting of (S40).

Images