JP2013103278A - Working detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working detection device capable of reliably working a workpiece and shortening a cycle time of the working.SOLUTION: A control device advances a rotary main shaft by a feed mechanism while rotating the rotary main shaft, as an advancing operation (S5). The control device then detects a working start P1 (S8) when a value of a load voltage V measured by a measurement device is continuously higher than a predetermined working initial voltage value V1 during a predetermined working initial time t1 (S6, S7) as an initial detection operation. Then, the control device detects a working completion P2 (S11) when the value of the load voltage V measured by the measurement device is continuously lower than a predetermined working terminal voltage value V2 during a predetermined working terminal time t2 (S9, S10) as a terminal detection operation after the detection of the working start P1. Thereafter, the control device retreats the rotary main shaft by the feed mechanism (S13) as a retreat operation when the working completion P2 is detected.

Description

  The present invention relates to a machining detection device capable of detecting the completion of machining by a signal from a measuring instrument when machining is performed by rotating a rotary tool.

  In factories that manufacture various machine parts, a processing device that performs processing with a rotary tool such as a drill is attached to the moving tip of an industrial robot, and the processing device is moved to a predetermined processing position on the workpiece by the industrial robot. It is moved to, and drilling processing etc. is performed. The processing apparatus includes a rotation main shaft that supports the rotary tool, and a feed mechanism that sends the rotation main shaft in the axial direction. Processing by a processing apparatus using an industrial robot is performed by moving a rotating main spindle forward by a predetermined amount by a feed mechanism and then moving it backward.

For example, in Patent Document 1, a drilling device having a rotary actuator that rotates a drill, a load torque detecting unit that detects a load torque of the rotary actuator, and a feed actuator that moves a processing head attached with the drill forward and backward. Is disclosed. In this drilling device, when the drill cuts the workpiece and the load torque reaches the maximum value and a certain time has elapsed, the drill is moved backward to sever the chips.
In Patent Document 2, when performing discharge hole machining, the voltage between the electrode and the workpiece is measured, and the state in which the first maximum voltage value is higher than the second maximum voltage value lower than this is the default. There is disclosed a penetration detection device that determines that a hole generated by discharge has penetrated when it occurs continuously more than the number of times. In this penetration detection device, it is possible to accurately detect that the discharge hole machining has penetrated.

Japanese Patent No. 4662104 JP-A-2005-144651

  By the way, when the workpiece has a dimensional variation such as a cast product, the processing such as drilling is surely performed on the workpiece only by detecting the completion of the processing by the feed amount of the rotary tool. I can't confirm what happened. For this reason, the feed amount of the rotary tool is slightly increased in consideration of dimensional variations. As a result, it is difficult to shorten the processing cycle time.

  The present invention has been made in view of such a background, and has been obtained in an attempt to provide a processing detection apparatus that can reliably process a workpiece and can shorten the cycle time of the processing. .

The present invention comprises a rotating spindle that is rotated by a rotary actuator;
A rotating tool attached to the rotating spindle;
A feed mechanism that is driven by a feed actuator and strokes the rotating spindle in the axial direction;
A measuring instrument for measuring a load voltage applied to the rotary actuator;
An output control for driving the rotary actuator and the feed actuator, and a control device for performing input control for reading the load voltage from the measuring instrument,
The controller is configured to advance the rotary spindle forward by the feed mechanism while rotating the rotary spindle;
An initial detection operation for detecting the start of machining when the value of the load voltage measured by the measuring instrument continuously becomes higher than a predetermined machining initial voltage value during a predetermined machining initial time;
After the start of machining is detected, the completion of machining is detected when the value of the load voltage measured by the measuring instrument is continuously lower than the predetermined machining end voltage value for a predetermined machining end time. End-of-life detection action to
The machining detection device is configured to sequentially perform a retreat operation for retreating the rotation main shaft by the feed mechanism when the completion of the machining is detected (claim 1).

When the workpiece is machined by the rotary tool, the machining detection device measures the load voltage applied to the rotary actuator and detects the machining start and machining completion, thereby detecting the workpiece by the rotary tool. Processing can be performed quickly and reliably.
When processing a workpiece with a rotary tool in the processing detection device, the control device sends a control signal to the rotary actuator to rotate the rotating spindle as a forward movement. Further, the control device sends a control signal to the feed actuator to drive the feed mechanism, and advances the rotating spindle by the feed mechanism.

  Next, the control device monitors the value of the load voltage measured by the measuring instrument as the initial detection operation. Then, the control device determines that the rotary tool has started machining the workpiece when the value of the load voltage continues to be higher than the predetermined machining initial voltage value for a predetermined machining initial time. The processing start is detected.

Next, the control device monitors the value of the load voltage measured by the measuring instrument after detecting the start of machining as the end detection operation. Then, the control device determines that the machining of the workpiece by the rotary tool is completed when the value of the load voltage continues to be lower than the predetermined machining end voltage value during the predetermined machining end time. To detect the completion of machining.
Thereafter, when the machining operation is detected as a backward movement, the control device sends a control signal to the feed actuator to drive the feed mechanism, and the feed mechanism causes the rotary spindle to move backward.

  In this way, in the said process detection apparatus, a process can be reliably processed with a rotary tool by detecting the process start and process completion by a control apparatus. Further, after the control device detects the completion of machining, the cycle time of machining by the rotary tool can be shortened by immediately performing the backward movement. Further, by performing the backward movement immediately after the control device detects the completion of machining, it is possible to prevent the feeding mechanism from sending an extra rotating tool in the axial direction even after the machining is completed. Thereby, it can also prevent that a rotary tool interferes with the site | part located in the to-be-processed object directly under the processed hole, and is damaged by itself.

  Therefore, according to the said process detection apparatus, a workpiece can be processed reliably and the cycle time of a process can be shortened.

The block diagram which shows the structure of the process detection apparatus concerning an Example. The flowchart which shows operation | movement of the process detection apparatus concerning an Example. The graph which shows the time passage of the load voltage V typically by taking the time t on the horizontal axis and taking the load voltage V applied to the rotation main axis on the vertical axis according to the example. The perspective view which shows the state which processes a to-be-processed object with the processing apparatus attached to the industrial robot concerning an Example. Explanatory drawing which shows the processing apparatus of the state before performing a drilling process with respect to a to-be-processed object concerning an Example. Explanatory drawing which shows the processing apparatus of the state which performs the drilling process with respect to a workpiece concerning an Example. Explanatory drawing which shows the processing apparatus of the state which performed the drilling process with respect to the to-be-processed object concerning an Example. BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows the processing apparatus of the state which retracted the rotating main shaft from the workpiece concerning an Example.

A preferred embodiment of the above-described processing detection apparatus will be described.
In the processing detection apparatus, the rotary tool includes a drill that performs drilling on the workpiece, a reamer that performs processing (roughing, finishing, etc.) for expanding a hole formed in the workpiece. It can be.
The load voltage measured by the measuring instrument can be a voltage generated by a load applied from the rotary tool to the rotary actuator when the rotary tool processes the workpiece.

The processing device is attached to the moving tip of the industrial robot, and after moving to a predetermined processing position by the movement of the moving tip, the control device sequentially performs the operations. (Claim 2).
In this case, the rotation spindle and the feed mechanism to which the rotary tool is attached can be sequentially moved to a plurality of machining positions on the workpiece by the industrial robot. Then, at each machining position, it is possible to perform machining with a rotary tool by performing forward, initial detection, final detection, and reverse operations.

The workpiece is a mold that is molded as a casting and presses the steel sheet. The mold includes a molding surface portion that molds the steel sheet and a molding surface portion below the molding surface portion. It has a reinforcing rib which reinforces the surface portion, and the hole processed by the rotary tool may be an air vent hole penetrating the molding surface portion.
In this case, even if the workpiece is a mold that is formed from a casting and is likely to have dimensional variations, the rotary tool is detected by detecting the start of processing and the completion of processing from the load voltage measured by the measuring instrument. Thus, it is possible to reliably perform the processing on the molding surface portion. Further, after detecting the completion of machining, the rotating tool is immediately retracted by the retracting operation, whereby the rotating tool can be prevented from interfering with the reinforcing rib and being damaged by itself.

Hereinafter, embodiments of the processing detection apparatus will be described with reference to the drawings.
FIG. 1 shows a configuration of the processing detection apparatus 1. As shown in FIG. 1, the machining detection device 1 of this example includes a machining device 2 and a control device 3. The processing apparatus 2 includes a rotary spindle 21 rotated by a rotary actuator 22, a rotary tool 23 attached to the rotary spindle 21, a feed mechanism 24 that is driven by a feed actuator 25 and strokes the rotary spindle 21 in its axial direction, And a measuring device 26 for measuring a load voltage V applied to the rotary actuator 22. The processing device 2 is configured to be operated by the control device 3. The control device 3 includes output control for driving the rotary actuator 22 and the feed actuator 25, and input control for reading the load voltage V from the measuring instrument 26. I do.

FIG. 2 shows a flowchart of the operation of the machining detection apparatus 1, and FIG. 3 schematically shows a graph of the elapsed time of the load voltage V measured by the measuring device 26.
The control device 3 is configured to sequentially perform the next forward operation, initial detection operation, end detection operation, and reverse operation.
As shown in FIG. 3, the control device 3 first advances the rotating main shaft 21 by the feed mechanism 24 while rotating the rotating main shaft 21 (step S3 in FIG. 2) as a forward movement operation (S5). Next, the control device 3 performs the initial detection operation when the value of the load voltage V measured by the measuring instrument 26 continuously becomes higher than the predetermined processing initial voltage value V1 during the predetermined processing initial time t1. (S6, S7), the processing start P1 is detected (S8). Next, the control device 3 detects the machining start P1 as an end detection operation, and then the value of the load voltage V measured by the measuring device 26 is greater than the predetermined machining end voltage value V2 for a predetermined machining end time t2. If it is continuously lowered (S9, S10), the machining completion P2 is detected (S11). Thereafter, the control device 3 retracts the rotating spindle 21 by the feed mechanism 24 when the machining completion P2 is detected as the retraction operation (S13).

Below, it demonstrates in detail with reference to FIGS. 1-8 about the process detection apparatus 1 of this example.
FIG. 4 shows a state in which the workpiece 5 is processed by the processing device 2 attached to the industrial robot 4.
As shown in the figure, the machining detection device 1 of this example performs drilling, and the rotary tool 23 of this example is a drill. The processing device 2 is attached to the moving tip portion 41 of the industrial robot 4 and is configured to perform each operation by the control device 3 after moving to a predetermined processing position by the movement of the moving tip portion 41. Yes. The industrial robot 4 has a plurality of joints that are rotated by a servo motor, and the position of the moving tip 41 can be moved three-dimensionally.

5 to 8 show the machining apparatus 2 that performs drilling on the workpiece 5, FIG. 5 shows a state before drilling, FIG. 6 shows a state where drilling is performed, and FIG. FIG. 8 shows a state after the drilling process, and a state after returning to the original position.
As shown in each drawing, the workpiece 5 to be processed by the processing detection apparatus 1 of this example is a mold 5 for pressing a steel plate. The mold 5 includes a forming surface portion 51 for forming a steel plate and reinforcing ribs 52 for reinforcing the forming surface portion 51 below the forming surface portion 51. The hole processed by the rotary tool 23 is an air vent hole 511 that penetrates the molding surface portion 51. The reinforcing ribs 52 are formed in a lattice shape. The reinforcing rib 52 is positioned immediately below the air vent hole 511 where the rotary tool 23 performs drilling.

As shown in FIG. 5, both the rotary actuator 22 and the feed actuator 25 of this example are constituted by a motor. The rotary spindle 21 has a mounting portion 211 for mounting the rotary tool 23 at the tip thereof, and the rotary tool 23 is mounted on the mounting portion 211 and rotates.
The feed mechanism 24 is configured to slide a slide portion 241 provided with the rotation main shaft 21 with a linear guide. The feed mechanism 24 is configured to convert the rotational force of the motor as the feed actuator 25 into a thrust force that slides the slide portion 241 with a feed screw or the like. The measuring device 26 is a voltage measuring device 26 that measures a load voltage V indicating the magnitude of the load torque applied to the rotation main shaft 21.

As shown in FIG. 1, the control device 3 of this example controls the rotation control unit 33 that controls the rotation of the rotary actuator 22, the feed control unit 34 that controls the feed actuator 25, and the industrial robot 4. The robot control unit 32 includes a rotation control unit 33, a feed control unit 34, and a sequencer control unit 31 to which the robot control unit 32 is connected. The forward operation, the initial detection operation, the end detection operation, and the reverse operation are executed by a control program built in the sequencer control unit 31. The value of the load voltage V measured by the measuring instrument 26 is read into the sequencer control unit 31 and used for the control program in the sequencer control unit 31.
Each operation by the sequencer control unit 31 is incorporated in a robot control program for controlling the movement of the moving tip 41 by the robot control unit 32.

Next, a method for drilling the workpiece 5 using the machining detection device 1 will be described with reference to the flowchart of FIG. 2 and the graph of FIG.
As shown in FIG. 4, the industrial robot 4 is instructed to store a plurality of machining positions for drilling the molding surface portion 51 of the mold 5.
As shown in FIG. 5, when processing the workpiece 5 by the processing detection device 1, the robot control unit 32 moves the moving tip 41 of the industrial robot 4 and attaches the rotary tool 23. The processing device 2 is moved to a target predetermined processing position. Then, the robot control unit 32 sends a movement completion signal to the sequencer control unit 31 (steps S1 and S2 in FIG. 2), and the industrial robot 4 moves until a sequence completion signal P2 is sent from the sequencer control unit 31. The tip 41 is put on standby.

The sequencer control unit 31 sends a control signal to the rotary actuator 22 via the rotation control unit 33 as a forward movement to rotate the rotary spindle 21 (S3). Further, the sequencer control unit 31 starts measuring the load voltage V by the measuring instrument 26 (S4). Further, the sequencer control unit 31 sends a control signal to the feed actuator 25 via the feed control unit 34 to drive the feed mechanism 24, and the feed mechanism 24 starts to advance the rotary spindle 21 from the original position in the processing apparatus 2. (S5).
Next, the sequencer control unit 31 monitors the value of the load voltage V measured by the measuring instrument 26 as an initial detection operation (S6). Then, as shown in FIG. 3, when the value of the load voltage V is continuously higher than the predetermined machining initial voltage value V1 during the predetermined machining initial time t1, the sequencer control unit 31 (S7) It is determined that the rotary tool 23 has started processing the workpiece 5, and the processing start P1 is detected (S8).

  As shown in FIG. 6, after starting drilling with the rotary tool 23, the sequencer control unit 31 controls the feed actuator 25 via the feed control unit 34 to perform drilling with the rotary tool 23. At this time, the sequencer control unit 31 repeats the operation of moving the rotation spindle 21 by a predetermined amount and the operation of moving the rotation main shaft 21 by a predetermined amount, and performs drilling while dividing chips discharged during drilling. As shown in FIG. 3, the load voltage V applied to the rotating spindle 21 measured by the measuring instrument 26 when performing this drilling processing is a rise in voltage due to machining and a drop in voltage due to machining pause. Are observed in a waveform that repeats (see symbol K).

  After detecting the machining start P1, the sequencer control unit 31 monitors the value of the load voltage V measured by the measuring instrument 26 after detecting the machining start P1 as an end detection operation (S9). As shown in FIG. 3, when the value of the load voltage V is continuously lower than the predetermined machining end voltage value V2 during the predetermined machining end time t2, as shown in FIG. 3 (S10), It is determined that the processing of the workpiece 5 by the rotary tool 23 is completed, and the processing completion P2 is detected (S11). At this time, the sequencer control unit 31 ends the measurement of the load voltage V by the measuring instrument 26 (S12). Thus, as shown in FIG. 7, the rotary tool 23 penetrates the molding surface portion 51 of the mold 5 and the drilling process is completed.

Next, when the sequencer control unit 31 detects the machining completion P2 as a backward operation, the sequencer control unit 31 sends a control signal to the feed actuator 25 via the feed control unit 34 to drive the feed mechanism 24, and the feed mechanism 24 drives the rotary spindle 21. Is moved backward (S13). When the rotary spindle 21 moves backward to the original position in the machining apparatus 2, the sequencer control unit 31 sends a machining completion P2 signal to the robot control unit 32. FIG. 8 shows a state in which the rotary spindle 21 is retracted to the original position in the processing apparatus 2.
Thereafter, the robot control unit 32 moves the moving tip 41 and the processing apparatus 2 of the industrial robot 4 to the next processing position, and the sequencer control unit 31 performs the same operation on the next processing position as described above. And drill holes.

  In this manner, in the processing detection device 1, the processing device 5 can be reliably processed by the rotary tool 23 by detecting the processing start P <b> 1 and the processing completion P <b> 2 by the control device 3. Further, after the control device 3 detects the machining completion P2, the machining cycle time by the rotary tool 23 can be shortened by immediately performing the backward operation. Further, the control device 3 performs the backward movement immediately after detecting the machining completion P2, thereby preventing the feeding mechanism 24 from sending the rotary tool 23 in the axial direction even after the machining is completed. be able to. Thereby, it can also prevent that the rotary tool 23 interferes with the reinforcement rib 52 located just under the processed hole in the metal mold | die 5 as the to-be-processed object 5, and is damaged by itself.

  Therefore, according to the said process detection apparatus 1, a process can be reliably performed to the to-be-processed object 5, and the cycle time of a process can be shortened.

DESCRIPTION OF SYMBOLS 1 Processing detection apparatus 2 Processing apparatus 21 Rotating spindle 22 Rotating actuator 23 Rotating tool 24 Feeding mechanism 25 Feeding actuator 26 Measuring device 3 Control apparatus 4 Industrial robot 41 Moving tip V Load voltage 5 Workpiece (mold)
51 Molded surface 52 Reinforcing rib

Claims (3)

A rotating spindle that is rotated by a rotating actuator; a rotary tool attached to the rotating spindle; a feed mechanism that is driven by a feed actuator to stroke the rotating spindle in the axial direction; and a measuring instrument that measures a load voltage applied to the rotary actuator. A processing device comprising:
An output control for driving the rotary actuator and the feed actuator, and a control device for performing input control for reading the load voltage from the measuring instrument,
The controller is configured to advance the rotary spindle forward by the feed mechanism while rotating the rotary spindle;
An initial detection operation for detecting the start of machining when the value of the load voltage measured by the measuring instrument continuously becomes higher than a predetermined machining initial voltage value during a predetermined machining initial time;
After the start of machining is detected, the completion of machining is detected when the value of the load voltage measured by the measuring instrument is continuously lower than the predetermined machining end voltage value for a predetermined machining end time. End-of-life detection action to
A machining detection device configured to sequentially perform a retraction operation for retreating the rotation spindle by the feed mechanism when the completion of the machining is detected.   2. The processing detection device according to claim 1, wherein the processing device is attached to a moving tip of an industrial robot and moves to a predetermined processing position by the movement of the moving tip, and then the control device. The processing detection apparatus is configured to sequentially perform the above operations. In the processing detection apparatus according to claim 1 or 2, the work is formed as a casting, and is a mold for pressing a steel plate,
The mold has a forming surface portion for forming the steel sheet, and reinforcing ribs for reinforcing the forming surface portion below the forming surface portion,
The hole to be processed by the rotary tool is an air vent hole penetrating the molding surface portion.

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