Workpiece handling system

Abstract

The present invention provides a workpiece transport system (1). The workpiece transport system (1) comprises: a robot (2) that transports a workpiece (W) taken out of a furnace to a stamping and forging device; a temperature measuring device (3) that measures the temperature distribution of the workpiece (W) during the transport process by the robot (2); and a heating device (4) that can locally heat the workpiece (W) in a low-temperature region of the temperature distribution measured by the temperature measuring device (3). Compared with the case where the workpiece (W) is stopped and heated, the workpiece transport system (1) can efficiently heat, shorten the operation cycle time, and make the temperature distribution of the workpiece (W) during the transport process appropriate, thereby stabilizing the quality of the workpiece (W).

Description

Technical Field

[0001] The present invention relates to a workpiece handling system. Background Art

[0002] There is known a workpiece conveying device that conveys a workpiece taken out of a furnace to a die during hot forging (for example, see Patent Document 1).

[0003] The workpiece transport device uses an infrared camera to detect the workpiece's posture and a robot to operate it, adjusting the workpiece's posture while transporting it to the mold. This reduces the time required to transport the workpiece and adjust its posture, thereby suppressing the temperature drop of the workpiece.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 5-92229 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] If the workpiece temperature drops partially during transfer from the furnace to the die due to heat dissipation, the quality of the hot-forged workpiece will vary. Therefore, it is desirable to maintain an appropriate temperature distribution during transfer to stabilize the workpiece quality.

[0009] Solutions for solving problems

[0010] One embodiment of the present invention is a workpiece transport system comprising: a robot that transports a workpiece taken out of a furnace to a stamping and forging device; a temperature measuring device that measures the temperature distribution of the workpiece during the transport process performed by the robot; and a heating device that can locally heat the workpiece in a low temperature area in the temperature distribution measured by the temperature measuring device. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a diagram showing the overall configuration of a workpiece transport system according to one embodiment of the present invention.

[0012] Figure 2 The contour lines are used to show the Figure 1 FIG. 1 is a diagram showing an example of temperature distribution in a workpiece obtained by a temperature measurement device of a workpiece transport system.

[0013] Figure 3 It is shown using contour lines Figure 1 A diagram showing an example of a target temperature distribution stored in a storage unit of a main control device of a workpiece transport system.

[0014] Figure 4 The slash is used to show the Figure 2 The temperature distribution and Figure 3 A diagram showing an example of a target temperature distribution and a low-temperature area that should be heated.

[0015] Description of reference numerals:

[0016] 1: Workpiece handling system

[0017] 2: Robot

[0018] 3: Temperature measuring device

[0019] 4: Heating device

[0020] 8: Camera (position detection device)

[0021] 11: Scanner

[0022] W: workpiece DETAILED DESCRIPTION

[0023] Hereinafter, a workpiece transport system 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0024] The workpiece conveying system 1 of this embodiment includes: a robot 2, which conveys the workpiece W heated in a heating furnace (furnace) to a stamping and forging device (not shown); a temperature measuring device 3, which measures the temperature distribution of the workpiece W; a heating device 4, which can locally heat the workpiece W; and a robot control device 7.

[0025] The robot 2 is, for example, a vertical six-axis articulated robot, and has a hand 6 at the tip of a wrist 5 for gripping a workpiece W. The motors driving the joints of the robot 2 are equipped with encoders (not shown) that detect the rotational angular position of each joint. A robot control device 7 connected to the robot 2 controls the robot 2 based on the position information detected by the encoders.

[0026] The temperature measuring device 3 is arranged at a midway position of the path where the robot 2 carries the workpiece W. It includes a camera (position detection device) 8 and an infrared radiation thermometer 9. The camera 8 takes an image of the workpiece W, and the infrared radiation thermometer 9 measures the temperature of the workpiece W. Figure 2 As shown, the temperature distribution inside the contour of the workpiece W captured by the camera 8 can be measured using the infrared radiation thermometer 9 .

[0027] like Figure 1 As shown, the heating device 4 includes a laser oscillator 10 that generates laser light, a scanner 11 that two-dimensionally scans the laser light emitted from the laser oscillator 10 , and a laser control device 12 that controls the laser oscillator 10 and the scanner 11 .

[0028] In the figure, reference numeral 13 denotes an optical fiber that guides the laser light emitted from the laser oscillator 10 to the scanner 11 .

[0029] The laser control device 12 includes a main control device 14, an output control device 15, and a scanner control device 16. The laser control device 12 is composed of a processor and a memory.

[0030] The main control device 14 includes a storage unit (not shown) that stores Figure 3 The target temperature distribution of the workpiece W is shown in FIG. Moreover, the main control device 14 measures the temperature measured by the camera 8 and the infrared radiation thermometer 9. Figure 2 The temperature distribution and the temperature stored in the storage unit Figure 3 The target temperature distribution is compared and extracted, for example Figure 4 The information of the low temperature area whose temperature is lower than the target temperature distribution is shown by the oblique lines.

[0031] The information on the low temperature region includes, for example, local position information (in a coordinate system fixed to the workpiece W) of the low temperature region within the outline of the workpiece viewed from below, and information on the temperature difference between the low temperature region and the target temperature distribution.

[0032] Main controller 14 also sequentially obtains position information of workpiece W held by hand 6 of robot 2 from robot controller 7. Specifically, it obtains angle information of each joint of robot 2 and calculates global position information (in a coordinate system fixed to the installation surface of robot 2) of workpiece W held by hand 6. Main controller 14 then sequentially calculates global position information of the low-temperature region based on the global position information of workpiece W and the extracted local position information of the low-temperature region.

[0033] The main control device 14 transmits the calculated global position information of the low-temperature region to the scanner control device 16 , and transmits information on the temperature difference between the extracted low-temperature region and the target temperature distribution to the output control device 15 .

[0034] The output control device 15 calculates the required intensity of the laser light based on the transmitted temperature difference information, and controls the laser oscillator 10 to emit the laser light having the calculated intensity.

[0035] Furthermore, the scanner control device 16 causes the scanner 11 to track the moving low-temperature region based on the global position information of the region, which is constantly moving, and controls the scanner 11 to continuously irradiate the low-temperature region with laser light. If the low-temperature region is small, the laser light is precisely irradiated into the low-temperature region; if the low-temperature region is large, the laser light is scanned across the entire low-temperature region.

[0036] Next, the operation of the workpiece transport system 1 of this embodiment configured as described above will be described.

[0037] When using the workpiece conveying system 1 of this embodiment to convey the workpiece W taken out from the heating furnace to the stamping and forging device, the hand 6 installed at the front end of the wrist 5 of the robot 2 is used to grasp the workpiece W and move the workpiece W to the field of view of the camera 8 and the measurement range of the infrared radiation thermometer 9.

[0038] Thereby, the contour shape of the workpiece W and the temperature distribution inside the workpiece W are acquired. The acquired information of the contour shape and temperature distribution of the workpiece W is sent to the main controller 14 of the laser controller 12 .

[0039] The main controller 14 compares the measured temperature distribution with the target temperature distribution stored in the storage unit, and extracts position information and temperature difference information of a low-temperature region within the contour of the workpiece W having a temperature lower than the target temperature distribution.

[0040] Then, main controller 14 calculates global position information of the low-temperature region based on the global position information of the workpiece W sequentially acquired from robot controller 7 and the local position information of the low-temperature region acquired from camera 8 .

[0041] The global position information of the low-temperature area calculated sequentially is sent to the scanner control device 16 to control the scanner 11 to continuously irradiate the low-temperature area with laser light.

[0042] The temperature difference information extracted by the main control device 14 is sent to the output control device 15 to adjust the intensity of the laser light output by the laser oscillator 10. Specifically, when the temperature difference is large, the laser light intensity is increased, and when the temperature difference is small, the laser light intensity is decreased.

[0043] As described above, according to the workpiece transport system 1 of this embodiment, the workpiece W taken out of the heating furnace is held by the hand 6 and transported by the robot 2 to the press forging device, and the temperature distribution is measured to extract the low temperature area.

[0044] Furthermore, the low-temperature region is continuously heated by laser irradiation during the conveyance process by the robot 2 , and the temperature difference between the low-temperature region and the target temperature distribution decreases.

[0045] In this case, the workpiece transport system 1 of this embodiment heats the workpiece W by following the scanner 11 during transport by the robot 2. This has the advantage of enabling efficient heating and shortening the cycle time compared to heating the workpiece W while the workpiece W is stopped.

[0046] Furthermore, the laser light can efficiently and locally heat the workpiece W. Furthermore, by scanning the laser light with the scanner 11 , there is an advantage in that the workpiece W can be sufficiently heated regardless of the size of the low-temperature region.

[0047] Thus, even if the temperature of the workpiece W partially decreases due to heat dissipation from the workpiece W, the temperature distribution of the workpiece W can be appropriately corrected during transportation, thereby stabilizing the quality of the workpiece W after forging.

[0048] In addition, in this embodiment, the scanner 11 follows (tracks) the movement of the workpiece W performed by the robot 2 so that the low-temperature area of the workpiece W is irradiated with laser light by the scanner 11. Alternatively, the workpiece W may be heated at a fixed position without tracking.

[0049] Furthermore, in this embodiment, it is possible to obtain information on the formability of the workpiece W after forging, and to correct the target temperature distribution in areas with poor formability. For example, this can be accomplished by increasing the temperature in the areas with poor formability within the target temperature distribution. This formability information can be obtained by measuring the workpiece W after forging, or by measuring the three-dimensional shape of the workpiece W after forging.

[0050] In this embodiment, a device that heats by irradiating laser light is exemplified as the heating device 4, but any other heating device 4 may be used instead. In addition, a six-axis multi-articulated robot is exemplified as the robot 2, but the present invention is not limited thereto, and any other type of robot may be used.

Claims

1. A workpiece handling system, characterized in that: have: A robot that carries workpieces from the furnace to the stamping and forging unit; a temperature measuring device for measuring a temperature distribution of the workpiece during handling by the robot; a main control device for sequentially acquiring the position of the workpiece during the handling process performed by the robot; as well as Heating device, The main control device compares the temperature distribution of the workpiece measured by the temperature measuring device with a target temperature distribution of the workpiece stored in advance to extract information of a low-temperature region in the workpiece having a temperature lower than that of the target temperature distribution, and sequentially calculates positions of the low-temperature regions based on the extracted information of the low-temperature regions and the sequentially acquired positions of the workpiece. When the main control device calculates the position of the low-temperature area, the heating device locally heats the calculated position.

2. The workpiece handling system according to claim 1, wherein: The heating device heats the calculated position so that the temperature distribution of the workpiece approaches the target temperature distribution.

3. The workpiece handling system according to claim 1, wherein: The heating device locally heats the calculated position by irradiating the calculated position with laser light.

4. The workpiece handling system according to claim 3, wherein: The heating device follows the calculated position to adjust the irradiation position of the laser light.

5. The workpiece handling system according to claim 3 or 4, characterized in that: The heating device includes a scanner configured to scan the laser beam at the calculated position.

6. The workpiece handling system according to claim 1, wherein: The heating device corrects the target temperature distribution based on information on the quality of the formability of the workpiece in the press forging device.

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