Work position automatic correction device for machine tool

Abstract

The present invention relates to an automatic workpiece position correction device for a machine tool, and more particularly to an automatic workpiece position correction device for a machine tool that enables accurate setting of the workpiece seating position for each cell using a workpiece transfer device (RGV) equipped with a position sensor. A workpiece position automatic correction device for a machine tool is characterized by comprising: a workpiece storage device comprising a plurality of cells capable of loading a workpiece and a pallet stay capable of mounting a pallet that is seated in each cell to fix the workpiece; and a workpiece transfer device formed between the workpiece storage device and the machine tool, wherein a position sensor is formed to locate the position of the pallet stay in each cell of the workpiece storage device when transferring a workpiece loaded in the workpiece storage device to the machine tool or when loading a workpiece that has completed processing back into the workpiece storage device, thereby enabling accurate seating of each workpiece at the loading position. In this device, the position sensor is composed of an upper position sensor and a side position sensor, a first pallet guide and a second pallet guide are formed on the upper surface of the pallet stay, and the pallet stay is characterized by having a side position identification hole and an upper position identification hole formed on one side of the first pallet guide or the second pallet guide and at the center of the upper surface.

Description

Technology Field

[0001] The present invention relates to an automatic workpiece position correction device for a machine tool, and more particularly to an automatic workpiece position correction device for a machine tool that enables accurate setting of the workpiece seating position for each cell using a workpiece transfer device (RGV) equipped with a position sensor. Background Technology

[0002] Machine tools are generally used as machines that create a required shape by using cutters such as cutting bits, drill bits, and milling cutters to rotate or reciprocate the workpiece or cutter to cut a workpiece (workpiece) made of a material such as metal into a desired shape.

[0003] To implement automation, such machine tools are equipped with a workpiece transfer device for removing a finished workpiece from the machine tool, loading the removed workpiece into a storage space, or feeding a workpiece to be processed into the machine tool.

[0004] Here, the workpiece transfer device for a machine tool comprises a base frame that moves along a rail (not shown) installed along the length of a production line for transferring a workpiece, a vertical frame formed vertically relative to the base frame and configured to move forward and backward, a horizontal frame configured to move up and down via the vertical frame and also capable of moving left and right, and a driving means, etc.

[0005] A workpiece transfer device for a machine tool with such a configuration allows a pallet for loading workpieces to be inserted into or withdrawn from the upper surface of the horizontal frame, thereby removing a finished workpiece from the machine tool, loading the removed workpiece into a storage space, or feeding a workpiece for processing into the machine tool.

[0006] Furthermore, in an environment where industrial automation is becoming widespread, automated systems that transport workpieces unmanned are becoming commonplace for machine tool workpiece transfer devices.

[0007] Typically, in workpiece transfer devices for machine tools, 10 to as many as 70 or more workpieces are operated in an unmanned automated manner. To automate these workpieces, the precise position coordinates of each workpiece loading position must be set. This process is called teaching.

[0008] However, conventional workpiece position correction for machine tools had the problem of reduced productivity because it required a significant amount of work time, as an operator had to enter the automation system, operate Rail Guided Vehicles (RGVs), and manually check and upload each workpiece position coordinate to the system.

[0009] In addition, there was a problem that the risk of safety accidents was high during work because the position coordinates of each workpiece had to be checked individually and uploaded to the system. Prior art literature

[0010] Publication No. 10-2023-0157712 The problem to be solved

[0011] Accordingly, the present invention has been devised to solve the aforementioned problems, and the objective of the present invention is to provide an automatic workpiece position correction device for machine tools that improves productivity and work safety by automatically checking each workpiece position coordinate and uploading it to a system. means of solving the problem

[0012] To achieve the above-mentioned objective, the present invention comprises a workpiece storage device comprising a plurality of cells capable of loading workpieces and a pallet stay capable of mounting a pallet that is seated in each cell to fix the workpiece, and a workpiece transfer device formed between the workpiece storage device and the machine tool, wherein a position sensor is formed to locate the position of the pallet stay in each cell of the workpiece storage device when transferring a workpiece loaded in the workpiece storage device to the machine tool or when loading a workpiece that has completed processing back into the workpiece storage device, thereby enabling accurate seating of each workpiece at the loading position, wherein the position sensor is composed of an upper position sensor and a side position sensor, a first pallet guide and a second pallet guide are formed on the upper surface of the pallet stay, and the pallet stay is characterized by having a side position identification hole and an upper position identification hole formed on one side of the first pallet guide or the second pallet guide and at the center of the upper surface.

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[0020] As described above, the present invention has the effect of increasing productivity by improving workability through the automation of the teaching operation of measuring the positions of dozens of workpieces.

[0021] In addition, the present invention has the effect of preventing safety accidents involving workers by automatically performing workpiece position correction. Brief explanation of the drawing

[0022] FIG. 1 is a schematic overall perspective view of an automatic workpiece position correction device for a machine tool according to a preferred embodiment of the present invention. FIG. 2 is a drawing of the main part of a workpiece storage device of an automatic workpiece position correction device for a machine tool according to a preferred embodiment of the present invention. FIG. 3 is a rear view of the entire workpiece storage device of an automatic workpiece position correction device for a machine tool according to a preferred embodiment of the present invention. FIG. 4 is an enlarged view of a pallet stay according to a preferred embodiment of the present invention. FIG. 5 is a drawing showing a workpiece moving device of an automatic workpiece position correction device for a machine tool according to a preferred embodiment of the present invention. FIG. 6 is an enlarged view of a fork assembly according to a preferred embodiment of the present invention. FIG. 7 is a schematic enlarged view of a key part of an X-axis driving unit according to a preferred embodiment of the present invention. FIG. 8 is a drawing showing the entire workpiece moving device according to a preferred embodiment of the present invention from the front. FIG. 9 is an enlarged view of the side position sensor according to the present invention illustrated in FIG. 8. FIG. 10 is an enlarged view of the upper surface position sensor according to the present invention illustrated in FIG. 8. FIG. 11 is a flowchart of the main parts of a method for automatically correcting the position of a workpiece using an automatic workpiece position correction device for a machine tool according to a preferred embodiment of the present invention. FIG. 12 is a drawing showing a point for calculating the twist angle position of a pallet stay through a position sensor during automatic workpiece position correction according to the present invention. Specific details for implementing the invention

[0023] Hereinafter, preferred embodiments according to the present invention will be described in more detail with reference to the attached drawings.

[0024] Here, components having the same function in all the drawings below use the same reference numerals, and repetitive descriptions are omitted. Additionally, it is specified that the terms described below are defined in consideration of their functions in the present invention and should be interpreted according to their inherent common meanings.

[0025] As illustrated in FIGS. 1 to 10, the automatic workpiece position correction device (100) for a machine tool according to the present invention is broadly divided into a workpiece storage device (110) and a workpiece transfer device (120).

[0027] The above workpiece storage device (110) comprises a plurality of cells (111) capable of loading a plurality of workpieces (not shown) and a pallet stay (112) capable of mounting a pallet (workpiece fixing device) (113) that is seated in each cell (111) to fix the workpiece.

[0028] A plurality of cells (111) capable of loading the above workpiece (not shown) can be formed in parallel vertically.

[0029] And, a pallet stay (112) forming a rail shape is formed in each of the above cells (111), and a first pallet guide (112a) and a second pallet guide (112b) are formed on the upper surface of the pallet stay (112).

[0030] Additionally, a side position identification hole (h1) is formed on one side of the pallet stay (112) to identify the position of the pallet (113).

[0031] Additionally, the pallet stay (112) has an upper surface position identification hole (h2) formed in the center of the upper surface of the first pallet guide (112a) or the second pallet guide (112b) to identify the position of the pallet (113).

[0033] The above workpiece transfer device (120) is formed between the workpiece storage device (110) and the machine tool (200) to transfer a workpiece loaded in the workpiece storage device (110) to the machine tool (200), or to load a workpiece that has been processed back into the workpiece storage device (110), by forming a position sensor (SENS) that finds the position of the pallet stay (112) of each cell (111) of the workpiece storage device (110), thereby enabling the workpiece to be accurately placed at each loading position.

[0034] To this end, the workpiece transfer device (120) comprises a fork assembly (121) that loads a workpiece and moves it in the Z-axis direction to transfer the workpiece, a Y-axis drive unit (122) that moves the fork assembly (121) in the Y-axis direction, and an X-axis drive unit (123) that moves the Y-axis drive unit (122) in the X-axis direction.

[0035] That is, the workpiece transfer device (RGV: Rail Guided Vehicles) (120) is composed of a fork assembly (121) that moves in the Z-axis direction to load or unload a workpiece and performs a forking operation, a Y-axis drive unit (122) that moves in the Y-axis direction to raise or lower the workpiece loaded (placed) on the fork assembly (121), and an X-axis drive unit (123) that moves in the X-axis direction.

[0037] The fork assembly (121) comprises a horizontal frame (121a) coupled to move up and down through the vertical frame (122a) of the Y-axis drive unit (122), a fork (121b) coupled to move left and right through the upper surface of the horizontal frame (121a), and a servo motor (not shown) coupled through one side of the horizontal frame (121a) to provide power.

[0038] In addition, the fork (121b) may have a plurality of fixing holes (not shown in the drawing) into which a pallet (113) for mounting a workpiece is inserted.

[0040] The above Y-axis drive unit (122) is formed to be positioned vertically through a base frame (123a) and consists of a vertical frame (122a) having LM Guides for up and down movement on both sides of the front, and an up and down drive means (122b) installed in the central part of the vertical frame (122a) for up and down movement.

[0042] The above X-axis drive unit (123) is composed of a rectangular base frame (123a), a roller formed on the base frame (123a), and a servo motor (123b), which is a power source that drives the mechanical load of the operating unit in response to an input signal from a separate control unit (not shown), and is configured to move along a rail (not shown) installed along the length of the production line.

[0043] Here, since the fork assembly (121), the Y-axis driving means (122), and the X-axis driving means (123) typically constitute a workpiece transfer device (120) that transfers a workpiece to a machine tool (200) or a workpiece storage device (110) that automatically processes a workpiece, a description of the specific configuration and operational relationship is omitted.

[0045] In addition, it is preferable that the above position sensor (SENS) be composed of a side position sensor (SENS1) and a top position sensor (SENS2).

[0046] That is, an upper surface position sensor (SENS2) for measuring the position (X,Z) of the first pallet guide (112a) and the second pallet guide (112b) is formed on one side of the upper surface of the fork assembly (121), and a side position sensor (SENS1) for measuring the position (X,Y) of the side position identification hole (h1) of the first pallet guide (112a) or the second pallet guide (112b) is formed on one side of the front end.

[0047] Here, the position sensor (SENS) composed of the side position sensor (SENS1) and the top position sensor (SENS2) is of various types, and representative sensors include camera-based position measurement sensors and three-dimensional range sensors for obtaining the shape or position of a three-dimensional object.

[0048] Through this, the twist angle θ of the pallet stay (112) is determined and the coordinates of the second pallet guide (112b) are calculated.

[0049] Here, the pallet stay (112) is formed with a first pallet guide (112a) formed on one side upper surface and a second pallet guide (112b) formed on the tile-side upper surface, and a side position identification hole (h1) is formed on one side of the pallet stay (112).

[0050] And, the side position identification hole (h1) is labeled P1, the first pallet guide (112a) is labeled P2, and the second pallet guide (112b) is labeled P3.

[0051] In addition, the present invention has a workpiece removal device (130) formed on one side of the workpiece storage device (110) for removing a workpiece, a workpiece transfer device (120) formed on the tile side, and a machine tool (200) formed on one side of the workpiece transfer device (120).

[0053] Meanwhile, the present invention may further provide a machine tool (200) equipped with the above-mentioned automatic workpiece position correction device (100).

[0055] The operational relationship of the present invention configured as described above is explained with reference to FIGS. 11 and FIGS. 12 as follows.

[0056] First, when a workpiece is fed into a machine tool (200) using the automatic workpiece position correction device (100) according to the present invention, or when a workpiece that has been processed from the machine tool (200) is removed from the workpiece removal device (130) or when a removed workpiece is loaded into a loading space, an automatic teaching program is executed using a separate control panel (not shown).

[0057] Accordingly, the workpiece transfer device (110) moves to the position of cell 1 (111).

[0058] That is, the servo motor (123b) of the X-axis drive unit (123) rotates in the forward or reverse direction, and thereby the base frame (123a) equipped with a roller moves forward or backward along the rail (not shown) of the production line where the machine tool (200) is installed, so that a workpiece can be fed, a finished workpiece can be removed, or a removed workpiece can be loaded into a loading space.

[0060] Next, the vertical driving means (122b) of the Y-axis driving unit (122) operates to feed a workpiece, remove a finished workpiece from the machine tool (200), or adjust the height of the horizontal frame (121a) on which the fork (121b) of the fork assembly (121) is formed by rotating a servo motor (not shown) in the forward or reverse direction so as to adjust the height to allow the workpiece to be fed, removed from the machine tool (200), or loaded into the loading space.

[0061] Next, after the height of the horizontal frame (121a) is adjusted, the horizontal frame (121a) of the fork assembly (121) is moved forward, backward, left, or right to measure the position (X, Z) of the first pallet guide (112a) and the second pallet guide (112b) through the upper position sensor (SENS2), and the position (X, Y) of the side position identification hole (h1) formed on the side of the first pallet guide (112a) or the second pallet guide (112b) is measured through the side position sensor (SENS1).

[0062] Here, it is checked whether the first pallet guide (112a), the second pallet guide (112b), and the side position identification hole (h1) of each cell (111), measured by the upper surface position sensor (SENS2) and the side position sensor (SENS1), are accurately recognized.

[0063] First, it is checked whether the side position identification hole (h1) formed on the side of the pallet stay (112) of cell 1 (111) is accurately recognized by the side position sensor (SENS1).

[0064] Then, when the side position identification hole (h1) formed on the side of the pallet stay (112) of the above cell 1 (111) is accurately recognized, the position coordinates of the side position identification hole (h1) are entered.

[0065] Next, when the first pallet guide (112a) formed on the upper surface of the pallet stay (112) of cell 1 (111) is accurately recognized by the upper surface position sensor (SENS2), the position coordinates of the first pallet guide (112a) are entered.

[0066] Through this, the twist angle θ of the pallet stay (112) is determined and the coordinates of the second pallet guide (112b) are calculated.

[0068] As an example, as shown in FIGS. 11 and 12, the seating position of a workpiece on the pallet (113) of the pallet stay (112) can be calculated through a position sensor (SENS) consisting of a side position sensor (SENS1) and a top position sensor (SENS2).

[0069] For example, the coordinates of the side position identification hole (h1) formed on the side of the pallet stay (112), i.e., P1 (x1,y1), and the first pallet guide (112a) formed on the top surface, i.e., P2 (x2,z2), are measured as follows using the side position sensor (SENS1) and the top position sensor (SENS2).

[0070] Here, y1 = y2 = y3 are considered to be identical.

[0071] P1 = x1, y1, z1 = x1, y1, z2-Lz

[0072] P2 = x2, y2, z2 = x2, y1, z2

[0073] P3 = x3, y3, z3 = x2+Lx, y1, z2

[0074] Δx = x2-x1,

[0075] θ = Lz*sin'(Δx / Lz)

[0076] Δz = z1+Lz-z2, Δz = Δx *tanθ

[0077] P3 = x2 + Lx*cosθ, y1, z2 + Lx*sinθ

[0079] Ideal location Actual location

[0080]

[0082] In this way, the position coordinates of the pallet stay (112) are measured from cell 2 (111), cell 3 (111), cell 4 (111)... to the last cell (111).

[0083] Additionally, if the position of the pallet stay (112) differs from the correct position, it is checked by moving ±10mm along the X-axis, and if it still differs from the correct position, it is checked by moving ±10mm along the Y-axis to correct the correct position of the pallet stay (112).

[0084] More specifically, for example, the position of each cell (111) pallet stay (112) is moved according to the set coordinates to start measurement, but if the actual installed pallet stay (112) is significantly out of position and the side position identification hole (h1) is not sensed, it is checked by moving along the X-axis at a specific interval (e.g., ±10mm), and if it is still not sensed, it is moved sequentially along the Y-axis to find and sense the side position identification hole (h1). However, the specific interval is preferably within the sensor's measurable radius.

[0086] And, when the position verification and correction of the palette stay (112) up to the last cell (111) is completed, the automatic teaching program is terminated.

[0088] Next, the above workpiece transfer device (120) is transferred to feed a workpiece into a machine tool (200), remove a workpiece that has been processed from a machine tool (200), or load a removed workpiece into a loading space.

[0089] Therefore, the present invention can replace the existing manual work performed by an operator by automating the teaching task of measuring the positions of dozens of workpieces in an unmanned automation device.

[0090] The present invention described above is not limited by the aforementioned embodiments and attached drawings, and it will be obvious to those skilled in the art that various substitutions, modifications, and changes to equivalent alternative embodiments are possible within the scope of the technical concept of the present invention. Explanation of the symbols

[0091] 100 : Automatic workpiece position correction device for machine tools 110 : Workpiece storage device 111 : Cell 112: Palette Stay 112a: First Palette Guide 112b : 2nd pallet guide h1 : Side position identification hole h2 : Top surface position identification hole 113 : Pallet 120 : Workpiece transfer device 121 : Fork assembly 121a: Horizontal frame 121b: Fork SENS: Position sensor SENS1: Side position sensor SENS2 : Top surface position sensor 122 : Y-axis drive unit 122a: Vertical frame 122b: Up-and-down driving means 123: X-axis drive unit 123a: Base frame 123b : Servo motor 130 : Workpiece removal device 200 : Machine tools

Claims

Claim 1 delete Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A workpiece storage device comprising a plurality of cells capable of loading a workpiece and a pallet stay capable of mounting a pallet that is seated in each cell to fix the workpiece, and a workpiece transfer device formed between the workpiece storage device and the machine tool, wherein a position sensor is formed to locate the position of the pallet stay in each cell of the workpiece storage device when transferring a workpiece loaded in the workpiece storage device to the machine tool or when loading a workpiece that has completed processing back into the workpiece storage device, thereby enabling accurate seating of each workpiece at the loading position, wherein the position sensor is composed of an upper position sensor and a side position sensor, a first pallet guide and a second pallet guide are formed on the upper surface of the pallet stay, and the pallet stay has a side position identification hole and an upper position identification hole formed on one side of the first pallet guide or the second pallet guide and in the center of the upper surface. Claim 8 delete

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