KR102493810B1 - Machining center having a linear automatic pallet changer and method of automatically changing pallets in the machining center - Google Patents

Abstract

A machining center and pallet exchange method are disclosed. The machining center includes a processing machine that includes a rectangular housing and performs machining on a workpiece, a pallet extending along the length of the housing and having an exchange area adjacent to the gate of the processing machine, a waiting area and a buffer area symmetrical to each other with respect to the exchange area. It is movably coupled to the table and pallet table and is disposed in the housing so as to be adjacent to the pallet transporter and the gate that moves the pallet that fixes the workpiece while reciprocating between the waiting area, exchange area, and buffer area, and transports the processing machine and the pallet in the exchange area. It includes a loading arm that performs pallet exchange between machines. Even while machining of the workpiece to be processed is being performed, the operation efficiency of the machining center can be remarkably improved by transferring the machined workpiece to the waiting area and performing the workpiece exchange.

Description

Machining center having a linear automatic pallet changer and method of automatically changing pallets in the machining center}

The present invention relates to a machining center and an automatic pallet exchange method, and more particularly, to a large machining center having a linear automatic pallet exchange device and a method for automatically exchanging pallets in the large machining center.

In general, a machining center is equipped with an automatic pallet changer (APC) that automatically exchanges pallets for fixing workpieces to be processed in order to increase productivity. In particular, in large machining centers such as door type processing machines, large-sized and heavy workpieces are frequently processed, so a linear APC provided integrally with the machining center is used instead of the rotary APC selectively coupled to the machining center. there is.

A general linear APC combines a pallet that can move reciprocally along the longitudinal direction of the machining center with an APC table disposed on the side of the machining center parallel to the door, and fixes a workpiece to be processed on the pallet to the machining area of the machining center. It has a loading and unloading structure. At this time, the pallet on which the workpiece is fixed is exchanged between the APC table and the machining center by a loading arm.

The pallet on which the processed workpiece is fixed is fixed to the loading arm, unloaded from the machining center to the exchange area of the APC table, and transported to the waiting area to be replaced with the workpiece to be processed. Subsequently, the pallet on which the workpiece to be processed is fixed is transferred to the exchange area and then loaded into the machining center by the loading arm. Accordingly, workpiece exchange is performed by pallet exchange between the APC table and the machining center. When the pallet exchange is completed, machining of the workpiece to be processed is performed inside the machining center.

Accordingly, workpiece processing in the machining center and workpiece exchange using the pallet device are sequentially performed, and workpiece processing in the machining center is stopped while pallet exchange is in progress. Accordingly, the total operation time of the machining center is determined by the time required for pallet exchange. In particular, pallet exchange and workpiece exchange in large machining centers are performed using various equipment due to the size and weight of the workpiece itself, so the pallet exchange time is significantly increased, and the overall operation efficiency of the machining center is greatly deteriorated.

In order to increase the operation efficiency of the machining center, a one-way linear exchanger is proposed in which the pallet moves in one direction along the longitudinal direction of the machining center to independently perform the loading/unloading of pallets, the supply of workpieces to be processed, and the removal of finished workpieces. there is.

According to the one-way linear exchanger, the removal area of the finished workpiece and the supply area of the workpiece to be processed are separated and arranged in a line with the exchange area where the machining center and the pallet are exchanged. Workpieces to be processed can be individually removed from the removal area while machining is performed in the machining center while a pair of pallets are transported in one direction from the supply area to the removal area via the exchange area. A new workpiece to be processed can be fixed to the pallet while processing in the machining center is in progress by configuring the facility to transfer the empty pallet from which the workpiece to be processed is removed from the removal area to the supply area. Accordingly, the removal of the finished workpiece, the supply of the workpiece to be processed, and the processing of the workpiece can be separated and independently performed.

However, in the one-way automatic pallet exchanger as described above, an APC table and workpiece replacement means are additionally required in the removal area as well as the supply area, and a connection means connecting the removal area and the supply area must be disposed, so the size and installation area of the APC table There are problems with all of this increasing.

In addition, since the conventional loading arm is driven by a hydraulic control method, it is difficult to perform precise position alignment during pallet loading and unloading, and there is a problem in that individual precision alignment steps are additionally performed by an operator.

The conventional loading arm performs precise position control by inserting a pin into an alignment hole, respectively, at a vertical position, which is an alignment position in a machining center, and a horizontal position, which is an alignment position in an APC table. However, since the position control precision of the hydraulic control is not sufficient to perform the pin insertion, the hydraulic control mode is switched to the manual control mode after the loading arm is moved by the hydraulic drive method to the vertical and horizontal positions, and the operator's manual operation is reduced. The pin alignment of the loading arm is performed by Accordingly, the pallet exchange time increases by the time required for manual positioning of the loading arm.

Accordingly, there is a need for a new machining center capable of performing workpiece replacement independently of machining without increasing the accuracy of position control of the loading arm and without increasing the complexity of equipment configuration and installation area.

An object of the present invention is to provide a machining center capable of increasing operation efficiency by performing a pallet operation for replacing a workpiece even during processing of the workpiece.

Another object of the present invention is to provide an automatic pallet exchange method capable of automatically performing a pallet exchange operation for replacing a workpiece even while the workpiece is being processed in a machining center as described above.

Automatic pallet changer according to exemplary embodiments of the present invention for achieving the above object is a processing machine including a rectangular housing having a length and width and performing machining on a workpiece by a numerical controller, the length of the housing A pallet table having an exchange area extending along a direction and adjacent to a gate of the processing machine, a waiting area and a buffer area positioned symmetrically with respect to the exchange area along the longitudinal direction, and movably coupled to the pallet table. A pallet transporter that moves a pallet holding a workpiece while linearly reciprocating between the waiting area and the exchange area and between the exchange area and the buffer area, and disposed in the housing so as to be adjacent to the gate and in the exchange area and a loading arm for performing pallet exchange between the processing machine and the pallet transporter.

According to other embodiments of the present invention for achieving the above object, a pallet exchanging method in a machining center is disclosed. First, a buffer pod and a transfer pod are prepared in an exchange area and a waiting area of a pallet table extending along the longitudinal direction on the side of a rectangular processing machine performing machining, and a second pallet in which a workpiece to be processed is stored in the transfer pod combine Subsequently, the first pallet on which the machined workpiece is fixed is unloaded from the processing machine to the buffer pod, and the second pallet is loaded from the transfer pod to the processing machine to exchange the first and second pallets in the exchange area. do. While machining of the workpiece to be processed is performed in the machine, the first pallet is transferred from the buffer pod to the transfer pod, and the transfer pod coupled with the first pallet is transferred to the waiting area.

As described above, according to the automatic pallet changing device and method according to exemplary embodiments of the present invention, a pallet conveyor having a pair of buffer pods and a transfer pod and linearly reciprocating along a pallet table, and a horizontal position and A loading arm driven by a servo motor is provided to temporarily stop at an arbitrary stop position on a rotational trajectory between vertical positions. Accordingly, even when machining is performed in the processing machine, the first pallet to which the machined workpiece is coupled may be transferred from the exchange area of the pallet table to the standby area. Therefore, even while machining of the workpiece to be processed is performed, the operation efficiency of the machining center can be remarkably improved by transferring the machined workpiece to the waiting area and performing the workpiece exchange.

1 is a perspective view showing a machining center according to an embodiment of the present invention.
Figure 2 is a plan view of the machining center shown in Figure 1;
FIG. 3 is a view in which first and second pallets in which a machined workpiece and a workpiece to be machined are combined are simultaneously disposed in the machining center shown in FIG. 1 .
Figure 4 is a perspective view showing in detail the pallet conveyor shown in Figure 1 according to an embodiment of the present invention.
5 is a cross-sectional view showing in detail the loading arm shown in FIG. 3 according to one embodiment of the present invention.
6A to 6L are configuration diagrams illustrating a process of exchanging pallets in the machining center shown in FIGS. 1 to 5 .

For the embodiments of the present invention disclosed in the text, specific structural or functional descriptions are only exemplified for the purpose of explaining the embodiments of the present invention, and the embodiments of the present invention may be implemented in various forms and the text It should not be construed as being limited to the embodiments described above.

Since the present invention can have various changes and various forms, specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific form disclosed, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms may be used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle. Other expressions describing the relationship between components, such as "between" and "directly between" or "adjacent to" and "directly adjacent to", etc., should be interpreted similarly.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "comprise" or "having" are intended to indicate that the described feature, number, step, operation, component, part, or combination thereof exists, but that one or more other features or numbers are present. However, it should be understood that it does not preclude the presence or addition of steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this application, they are not interpreted in an ideal or excessively formal meaning. .

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail.

1 is a perspective view showing a machining center according to an embodiment of the present invention, and FIG. 2 is a plan view of the machining center shown in FIG. FIG. 3 is a view in which first and second pallets in which a machined workpiece and a workpiece to be machined are combined are simultaneously disposed in the machining center shown in FIG. 1 .

1 to 3, a machining center 1000 according to an embodiment of the present invention includes a rectangular housing 110 having a length and width, and controls a workpiece (not shown) by a numerical controller 120. A processing machine 100 performing machining, an exchange area E extending along the longitudinal direction I of the housing 110 and adjacent to the gate G of the processing machine 100 and the longitudinal direction I Pallet table 200 having a waiting area S and a buffer area B located symmetrically with respect to the exchange area E, and movably coupled to the pallet table 200, the waiting area A pallet transporter (300) for moving pallets (P1, P2) holding workpieces while reciprocating linearly between (S) and the exchange area (E) and between the exchange area (E) and the buffer area (B). ), and a loading arm 400 disposed on the housing 110 adjacent to the gate G and performing pallet exchange between the processing machine 100 and the pallet transfer machine 200 in the exchange area E. ). Preferably, a workpiece replacement unit (not shown) may be further disposed in the waiting area to exchange a workpiece to be processed and a workpiece that has been processed.

As one embodiment, the processing machine 100 includes a machine tool (not shown) that is controlled according to a processing program input to a numerical controller 120 and automatically processes a workpiece. Accordingly, machining of the workpiece is automatically performed through a series of processes controlled by the numerical controller 120 .

In this embodiment, the processing machine 100 is provided as a horizontal machining center capable of processing large-sized workpieces. In particular, when processing a large workpiece, since it is not easy to separate the workpiece from the pallet, the workpiece fixed to the pallet is processed after being supplied to the processing machine 100 integrally with the pallet.

The spindle unit (S) in which the machine tool is fixed and processes the workpiece is installed in a work space separated from the outside by the housing 110, and while processing of the workpiece is in progress, the work space is sealed from the outside to create an airtight space. Thus, stability and reliability of workpiece processing can be increased. The working space is selectively closed by a gate G provided on the side of the housing 110 .

The housing 110 is provided as a rectangular structure having a certain width and length and sufficient rigidity and strength to separate the work space and the external environment. A side portion of the housing 110 is provided with a gate G that can be selectively opened. The gate (G) is opened during loading and unloading of the workpiece and closed during machining of the workpiece to form the work space as a closed space.

Although not shown, the machining center M is equipped with a plurality of tools required for machining the workpiece and a tool magazine controlled to provide tools suitable for the machining step, tools suitable for cutting conditions Ancillary devices such as an automatic tool changer (ATC) capable of automatically exchanging a tool and an attachment changer (AAC) automatically exchanging an attachment corresponding to the tool may be further provided. there is. Accordingly, the machining center (M) can automatically perform multi-axis machining or multi-process machining according to the design data input to the numerical controller 120 .

As one embodiment, the pallet table 200 is disposed to extend along the longitudinal direction (I) on the side of the housing 110 and can support a pallet (P) and a workpiece (not shown) located on the top. It is provided as a rectangular structure having sufficient strength to

For example, the pallet table 200 includes an integral table body 210 having a three-dimensional shape with high strength and high rigidity, and a support part 220 supporting the table body 210 and fixing it to the floor. The table body 210 is provided as a rectangular steel plate extending along the longitudinal direction I of the housing 110 on a side adjacent to the gate G of the processing machine 100, and the support part 220 is the table body 210 ) consists of a number of columns extending from the bottom to the bottom.

In particular, the pallet table 200 has an exchange area E located adjacent to the gate G and adjacent to the work space of the processing machine 100 and the exchange area (E) along the longitudinal direction (I). It is divided into a waiting area (S) and a buffer area (B) located symmetrically with respect to E). Accordingly, the waiting area S and the buffer area B are located at both ends of the pallet table 200, respectively, and the exchange area E is located adjacent to the gate G between them.

In particular, in this embodiment, the first holding part H1 of the loading arm 400, which will be described later, is provided at the boundary between the exchange area E, the waiting area S, and the buffer area B, so that the pallet conveyor 300 ) Provides a horizontal position HP, which is a horizontal alignment position of the loading arm 400 for separating the pallets P1 and P2 from each other.

As an embodiment, the pallet transporter 300 is movably coupled to the pallet table 200 and moves between the exchange area E, the buffer area B and the waiting area S according to a predetermined driving algorithm. move linearly As the pallet transporter 300 moves, the pallets P1 and P2 move linearly between the exchange area E, the buffer area B, and the waiting area S.

4 is a perspective view showing in detail the pallet conveyor shown in FIG. 1;

1 to 4, the pallet transporter 300 includes a pallet pod 310 accommodating pallets P1 and P2, a linear drive unit 320 for linearly moving the pallet pod 310, and A transfer power source 330 providing a transfer driving force to the linear drive unit 320 is included.

For example, the pallet pod 310 includes a base plate 311, a support part 312 extending downward from the side of the base plate 311 to cover the side of the table body 210, and the base plate It protrudes from 311 and includes a plurality of pallet fixing ends 313 for fixing pallets P1 and P2.

The base plate 311 is provided as a rectangular flat plate having a width corresponding to the width of the table body 210 and a length sufficient to accommodate the pallets P1 and P2. In particular, since strength enough to support and move the pallets P1 and P2 combined with large-sized workpieces is required, it is provided as a flat plate having sufficient thickness.

The support portion 312 extends downward from both sides of the base plate 311 to cover the side portion of the table body 210 . At this time, the support part 312 is spaced apart from the sidewall of the table body 210 so as not to contact the table body 210 while the base plate 311 moves along the rack 321 described later. Therefore, the support part 312 increases the stability of the coupling between the base plate 311 and the table body 210 without interfering with the movement of the base plate 311 .

The pallet fixing end 313 protrudes from the base plate 311 to have a predetermined height, and a coupling protrusion is disposed at the upper end to engage with coupling holes (not shown) provided on the rear surfaces of the pallets P1 and P2. . Accordingly, the pallets P1 and P2 are coupled to the pallet fixing end 313 and fixed to the pallet pod 310.

A plurality of pallet fixing ends 313 are uniformly distributed on the entire surface of the base plate 311 to uniformly support the pallets P1 and P2. In particular, a fixing tab 313a having a length corresponding to the width of the base plate 311 along the second direction (II) is provided at an end portion of the base plate 311 in the longitudinal direction, and an upper portion of the fixing tab 313a is provided. A coupling protrusion is disposed on. Accordingly, the stability of the coupling between the pallets P1 and P2 and the base plate 311 may be increased. The pallet fixing end 313 is provided as a plurality of protrusion structures uniformly distributed over the entire surface of the base plate 311 in the area except for the edge portion, but in the edge portion, on the upper surface of the fixing tab 313a having the same length as the width Coupling protrusions are provided to significantly increase the coupling stability of the pallets (P1, P2) and the pallet pod (310).

In particular, the fixing tab 313a improves the stability of the coupling between the pallet grip 430 and the pallets P1 and P2 by providing a reference surface when the pallet grip 430 to be described below protrudes from the lower portion of the pallets P1 and P2. can be raised

Since the pallet fixing end 313 has a certain height, the pallets P1 and P2 are spaced apart from the surface of the base plate 311, and a separation space is provided between the rear surface of the pallet and the base plate 311. The pallet grip 430 protrudes into the separation space, and the transfer power source 330 may also be disposed on the upper surface of the base plate 311 .

In this embodiment, the pallet pod 310 reciprocates between the exchange area E and the buffer area B and includes a buffer pod 310a selectively accommodating the pallets P1 and P2 and the exchange area E. A transfer pod 310b reciprocates between the area E and the waiting area S and selectively accommodates the pallets P1 and P2.

The buffer pod 310a and the transfer pod 310b may be selectively combined with a first pallet P1 to which the finished workpiece is coupled or a second pallet P2 to which the workpiece to be processed is coupled according to the pallet exchange step. .

The linear drive unit 320 is controlled by a transport power source to linearly move the pallet pod 310 .

For example, the linear driving unit 320 is fixed to the upper surface of the table body 210 and a rack 321 extending along the first direction and a plurality of racks fixed to the rack 321 and rotating according to the transfer of the rack It includes a pinion (not shown) of

The rack 321 is provided as a single linear structure extending along the first direction (I), and the pinion is coupled to the rack 321 and is arranged in a plurality so as to be coupled to the buffer pod 310a and the transfer pod 310b, respectively. do. That is, the pinion is individually connected to the buffer pod 310a and the transfer pod 310b but connected to the same rack 321.

Accordingly, according to the linear transfer of the rack 321, the buffer pod 310a and the transfer pod 310b are simultaneously linearly transferred in the same direction.

The transfer power source 330 is disposed in the pallet pod 310 to control the operation of the linear drive unit 320 . In this embodiment, the transfer power source 330 is disposed on the upper surface of the buffer pod 310a to have a height smaller than that of the fixing tab 313a. Accordingly, even when the pallets P1 and P2 are coupled to the pallet fixing end 313, the transfer power source 330 can be stably disposed in the separation space between the base plate 311 and the pallets P1 and P2. there is.

In this embodiment, the transfer power source 330 applies a linear driving force to the rack 321 to linearly move the rack 321 forward (FW) or backward (BW) along the first direction. Accordingly, the pallet pod 310 also linearly moves forward (FW) or rearward (BW) at the same time. In particular, since the buffer pod 310a and the transfer pod 310b are driven by the same rack 321, they linearly move along the same direction at the same time.

For example, the transfer power source 330 may be composed of a motor generating driving force by power or a hydraulic pressure generator generating driving force by hydraulic pressure. In the case of this embodiment, the transfer power source 330 is composed of a hydraulic controller to transfer a workpiece having a large size. However, when it is necessary to precisely control the position of the pallet pod 310, it is obvious that it may be configured as a servo motor.

The transfer power source 330 is connected to the numerical controller 120 by a signal line (SL). Accordingly, the driving of the pallet transfer machine 300 can be automatically controlled in response to the operation steps of the machining center 1000 .

In one embodiment, the loading arm 400 couples or separates the pallets P1 and P2 from the pallet pod 310 to perform pallet exchange in the exchange area E.

5 is a cross-sectional view showing in detail the loading arm shown in FIG. 3 according to one embodiment of the present invention.

Referring to FIG. 5, the loading arm 400 has a rectangular body 410 fixed to the housing 110 so as to be able to rotate in the first direction I as a rotational axis at the side of the gate G. , a horizontal position (HP) connected to the body 410 and the pallet table 200 so that the rear surface of the body 410 faces the upper surface of the pallet table 200 and the rear surface of the body 410 is The rotary drive unit 420 rotates between the vertical position VP positioned parallel to the side surface of the housing 110, and protrudes to the outside of the body 410 at the horizontal position HP to the pallets P1 and P2 It includes a pallet grip 430 coupled with, and a loading power source 440 that provides a loading driving force to the rotary driving unit 420.

The body 410 is provided in a box shape extending from a lower end to an upper part of the housing 110 and having an inner space in a rotating part (not shown) provided in the lower part of the housing 110 . Therefore, the upper end of the body 410 is disposed on the upper end of the housing 110 . A pallet grip 430 and a loading power source 440 are disposed inside the body 410 .

In this embodiment, the body 410 is provided as a pair of rectangular boxes disposed on both sides of the gate (G). A pair of rectangular boxes have the same structure and rotate simultaneously, so that the loading arm 400 fixes the pallets P1 and P2 at both side ends.

At this time, the table body (table body 210) and the housing 110 have first and second holding parts H1 capable of accommodating the body 410 at the horizontal position HP and the vertical position VP. , H2) is provided.

The rotary driving unit 420 includes a driving rod that is connected to the body 410 and the first holding unit H1 of the pallet table 200 and performs a reciprocating piston motion. The end of the driving rod is positioned such that the rear surface of the body 410 is in a horizontal position (HP) facing the upper surface of the table body 210 and the rear surface of the body 410 is parallel to the side surface of the housing 110. It is configured to change along the rotational trajectory between the vertical positions VP. Accordingly, the driving rod reciprocates between the minimum position at which the body 410 is positioned at the first holding part H1 and the maximum position at which the body 410 is positioned at the second holding part H2.

The pallet grip 430 is disposed inside the body 410 to extend along the longitudinal direction of the body 410 . In particular, the pallet grip 430 has a length corresponding to the width of the table body 210 at the horizontal position HP.

When the body 410 is aligned with the first holding part H1, a loading gripper (not shown) protrudes from the side end of the pallet grip 430 along the first direction I, and the pallet pod 310 It is coupled to the back of the fixed pallet (P1, P2). At this time, the loading fixing part extends into the space between the table body 210 and the pallets P1 and P2 so as not to interfere with the pallet fixing end 313 based on the upper surface of the fixing tab 313a.

When the coupling between the loading fixture and the pallets P1 and P2 is completed, the coupling between the pallet fixing end 313 and the fixing tab 313a and the pallets P1 and P2 is released. Accordingly, the combination of the pallets P1 and P2 with the pallet pod 310 is dissolved and fixed to the pallet grip 430 .

The loading power source 440 is disposed inside the body 410 to provide driving power to the rotary driving unit 420 and the pallet grip 430 . In this embodiment, the loading power source 440 includes a servomotor that can easily adjust the rated output according to the load of the workpiece to be processed and has excellent position control characteristics.

The conventional loading power source 440 is composed of a hydraulic controller, and due to the characteristics of the hydraulic controller, the rotary drive unit at an arbitrary stop position (TP) on a rotational trajectory (RC) between a horizontal position (HP) and a vertical position (VP). It is difficult to accurately pause 420.

However, in the case of the present embodiment, the loading power source 440 is composed of a servomotor using power, so that position control characteristics can be remarkably improved compared to conventional hydraulic controllers. Accordingly, the loading arm 400 can be accurately stopped at the stop position TP, which is an arbitrary position on the rotational trajectory RC. That is, by temporarily stopping the rotary drive unit 420 at any position on the rotation trajectory RC, the loading arm 400 can be stopped not only in the horizontal position HP and the vertical position VP but also in the temporary position TP. .

As will be described later, by stopping the loading arm 400 at an arbitrary stop position TP between the horizontal position HP and the vertical position VP, the machine 100 independently palletizes the workpiece regardless of machining. exchange can be performed. Accordingly, it is possible to remarkably increase the pallet exchange efficiency of the automatic linear pallet changer and increase the operation efficiency of the machining center.

At this time, the temporary stop position TP is separated from the buffer pod 310a while the empty buffer pod 310a is transferred to the buffer area B, and the pallets P1 and P2 coupled to the pallet grip 430 ) and is determined as the anti-collision angle (θ) measured along the rotational trajectory (RC) from the upper surface of the table body 210 to prevent collision. That is, the temporary stop position TP is uniquely determined by the anti-collision angle measured counterclockwise along the rotational trajectory RC from the upper surface of the table body 210 of the first holding part H1. .

In a state where the loading arm 400 to which the pallets P1 and P2 separated from the buffer pod 310a are fixed is stopped at the temporary stop position TP instead of the vertical position VP, the buffer pod 310a is moved to the exchange area. It is possible to transfer from (E) to the buffer area (B) and place the transfer pod 10b) in the exchange area (E).

At this time, since machining of the workpiece is being performed in the processing machine 100, since the second pallet P2 to which the workpiece to be processed is fixed is already located at the gate G, the loading arm 400 is moved to the vertical position ( VP) cannot be moved.

However, according to the machining center according to the present invention, it is possible to prevent interference and collision between the pallet pod 310 and the first pallet P1 to which the machined workpiece is coupled rather than the vertical position VP of the loading arm 400. After the exchange of the buffer pod (310a) and the transfer pod (310b) is completed, the pallet exchange is completed by moving it from the temporary position (TP) to the horizontal position (HP). can Accordingly, pallet exchange efficiency can be increased by performing pallet exchange between the buffer pod 310a and the transfer pod 310b independently of machining in the processing machine 100 .

Hereinafter, a method of exchanging a pallet in the machining center shown in FIGS. 1 to 5 according to an embodiment of the present invention will be described in detail.

6A to 6L are configuration diagrams illustrating a process of exchanging pallets in the machining center shown in FIGS. 1 to 5 .

Referring to FIG. 6A, first, buffer pods 310a and buffer pods 310a and Prepare the transfer pod 310b. A second pallet P2 for fixing a workpiece to be processed is disposed on the transfer pod 310b. The workpiece to be processed (raw product, RP) is stored on the workpiece carrying deck (D) and supplied to the machining center (1000).

When the alignment of the transport deck (D) and the pallet table (200) is completed and the control system for the operation of the transport deck (D) is interlocked with the numerical controller (120) of the machining center (1000), the pallet exchange preliminary work is completed. do.

At this time, since the machining machine 100 is performing machining on the previous workpiece, the loading arm 400 is accommodated in the second holding part H2 of the housing 110 and positioned in a vertical position.

Referring to FIG. 6B , when the machining of the machine 100 is completed and workpiece exchange is required, the numerical controller 120 transmits a workpiece exchange signal. Accordingly, the workpiece to be processed (RP) provided on the deck (D) is loaded into the transfer pod (310b) and fixed to the second pallet (P2).

Subsequently, as shown in FIG. 6C, the first pallet P1 on which the machined workpiece P is fixed is unloaded from the processing machine 100 and coupled to the buffer pod 310a. At this time, the loading arm 400 is combined with the first pallet P1 fixed to the workpiece P processed at the vertical position VP and rotates to the horizontal position HP. Accordingly, the loading arm 400 is fixed to the first holding part H1, which is a boundary area between the buffer area B and the exchange area E and between the exchange area E and the waiting area S. .

Subsequently, the coupling between the loading arm 400 and the first pallet P1 is released, and the first pallet P1 is coupled to the buffer pod 310a.

Accordingly, in the waiting area (S), the second pallet (P2) to which the workpiece (RP) to be machined is fixed is coupled to the transfer pod (310b), and in the exchange area (E), the second pallet (P2) to which the workpiece (P) to be machined is fixed is fixed. 1 pallet (P1) is coupled to the buffer pod (310a).

Although the present embodiment discloses that the loading of the workpiece to be processed (RP) into the transfer pod (301b) and the unloading of the finished workpiece (P) into the buffer pod (310a) are carried out separately, it can be performed simultaneously. self-explanatory

Referring to FIG. 6D, by transferring the rack 321 in the forward direction (FW), the buffer pod 310a and the transfer pod 310b are simultaneously transferred in the forward direction to form a buffer area B and an exchange area ( placed in E).

First, the loading arm 400 located at the horizontal position HP is returned to the vertical position VP, which is the boundary area between the buffer area B, the exchange area E and the waiting area S. 1 Open the holding part (H1). Accordingly, the upper surface 210 of the table of the first holding part H1 is exposed.

Subsequently, when the rack 321 is linearly transferred in the forward direction FW, the buffer pod 310a and the transfer pod 310b are simultaneously transferred along the forward direction by the movement of the pinion. Accordingly, the buffer pod 310a is transferred from the exchange area E to the buffer area B, and the transfer pod 310b is transferred from the waiting area S to the exchange area E.

That is, the second pallet P2 is located in the exchange area E and prepared to be loaded into the processing machine 100, and the first pallet P1 is prepared to be transferred to the waiting area S.

Referring to FIG. 6E , the second pallet P2 is separated from the transfer pod 310b and loaded into the processing machine 100 .

When the loading arm 400 moves from the vertical position VP to the first holding part H1 and is positioned at the horizontal position HP, the coupling between the transfer pod 310b and the second pallet P2 is released. and is fixed to the pallet grip 430 of the loading arm 400. Subsequently, the loading arm 400 is moved to the second holding part H2 and positioned in a vertical position. Then, the coupling between the second pallet P2 and the loading arm 400 is released and fixed inside the processing machine 100 by a pallet coupling part (not shown) of the processing machine 100 .

Thereafter, the processing machine 100 performs machining on the substrate RP to be processed.

Accordingly, the workpiece exchange between the machined workpiece P and the machined workpiece RP, which has been machined in the processing machine 100, is completed. Thereafter, the processed workpiece P is transferred to the waiting area S and transferred to the workpiece carrying deck D, regardless of machining in the processing machine 100 .

In this embodiment, the first pallet P1 is transferred from the buffer pod 310a to the transfer pod 310b while machining of the workpiece RO to be processed is performed in the processing machine 100, and The transfer pod (310b) having one pallet (P1) is transferred to the waiting area (S).

Referring to FIG. 6F, the buffer pod 310a and the transfer pod 310b are simultaneously transported in the backward direction BW and positioned in the exchange area and the waiting area, respectively.

For example, when the rack 321 is linearly transferred in the backward direction BW, the buffer pod 310a and the transfer pod 310b are simultaneously transferred along the backward direction by the movement of the pinion. Accordingly, the buffer pod 310a is transferred from the buffer area B to the exchange area E, and the transfer pod 310b is transferred from the exchange area E to the waiting area S.

That is, the second pallet (P1) to which the processed workpiece (P) is coupled is located in the exchange area (E) again.

Referring to FIG. 6G , the first pallet P1 is separated from the buffer pod 310a by moving the loading arm 400 from the vertical position VP to the horizontal position HP.

The loading arm 400 rotates from the second holding part H2 to the first holding part H1 and is positioned in a horizontal position. When the loading arm 400 is positioned in a horizontal position, the coupling between the buffer pod 310a and the first pallet P1 is released and the first pallet P1 is coupled to the loading arm 400.

Referring to FIG. 6H, the loading arm 400 is stopped by rotating the loading arm 400 from the horizontal position HP by the anti-collision angle θ along the rotational trajectory RC connecting the horizontal position HP and the vertical position VP. It is temporarily located at the position (TP).

When the loading arm 400 coupled with the first pallet P1 is rotated along the rotational trajectory RC, the first pallet P1 and the loading arm 400 are transported toward the second holding part H2. However, in the processing machine 100, since the second pallet P2 is already coupled and machining is performed, it moves only to the stop position TP, which is an arbitrary position, without moving to the second holding part H2.

At this time, since the loading power source 440 is composed of a servo motor with excellent position control characteristics, the loading arm 400 can be accurately stopped at the minimum position where the machined workpiece P and the pallet pod 310 do not interfere. there is.

When the processing position (TP) is determined to be close to the processing machine 100 by rotating more than the minimum position, the loading arm 400 rotates more than necessary, resulting in a waste of driving energy, and by rotating less than the minimum position, When the processing position TP is determined to be close to the pallet transporter 300, a collision between the first pallet P1 and the pallet pod 310 is caused.

Accordingly, the anti-collision angle θ is determined at the minimum position that does not cause a collision between the first pallet P1 and the pallet pod 310, and the loading arm 400 is moved by the servo motor to the anti-collision angle θ ) degrees and stops. Accordingly, the loading arm 400 is accurately stopped at the stop position TP.

Since the size of the finished workpiece (P) is variously set according to the type of machining, the temporary stop position (TP) may be variously changed according to the finished workpiece (P). At this time, even if the stop position TP varies according to the size of the finished workpiece P, the loading arm 400 is placed at the stop position TP corresponding to the finished workpiece P due to the excellent position control characteristics of the servo motor. ) can be accurately stopped.

Accordingly, the first pallet P1 is separated from the buffer pod 310a, but is positioned away from the processing machine 100. That is, both the buffer pod 310a and the transfer pod 310b are formed as empty pods, and the first pallet P1 is positioned above the buffer pod 310a.

At this time, the temporary stop position TP is specified as a position rotated by a predetermined angle in a counterclockwise direction along the rotational trajectory RC from the surface of the table body 210 of the first holding part H1. Separating the first pallet P1 from the buffer pod 310a moves the transfer pod 310b to the exchange area E, while the buffer pod 310a or the transfer pod 310b and the first pallet P1 Since the purpose is to prevent interference or collision of , the rotation angle is determined as an anti-collision angle (θ) that can sufficiently prevent a collision between the first pallet (P1) and the pallet pod 310.

That is, when the first pallet P1 is located at the stop position TP, the pallet pod 310 can freely linearly move on the pallet table 200 without interference or collision with the first pallet P1. .

Referring to FIG. 6I, the buffer pod 310a and the transfer pod 310b, which are empty pods, are transported in the forward direction FW and positioned in the buffer area B and the exchange area E, respectively.

When the rack 321 is linearly transferred in the forward direction (FW), the buffer pod 310a and the transfer pod 310b are simultaneously transferred along the forward direction by the movement of the pinion. Accordingly, the buffer pod 310a is transferred from the exchange area E to the buffer area B, and the transfer pod 310b is transferred from the waiting area S to the exchange area E.

Accordingly, the transfer pod 310b prepares to receive the first pallet P1 in the exchange area E.

Referring to FIG. 6J , the first pallet P1 is coupled to the transfer pod 310b by rotating the loading arm 400 from the stop position TP to the horizontal position HP.

The loading arm 400 moves from the stop position TP to the horizontal position by rotation. When the loading arm 400 is positioned in a horizontal position, the coupling between the loading arm 400 and the first pallet P1 is released and the first pallet P1 is coupled to the transfer pod 310b.

Referring to FIG. 6K, the buffer pod 310a and the transfer pod 310b are simultaneously transported in the backward direction BW and positioned in the exchange area E and the waiting area S, respectively.

When the rack 321 is linearly transferred in the backward direction (BW), the buffer pod 310a and the transfer pod 310b are simultaneously transferred along the backward (BW) direction by the movement of the pinion. Accordingly, the buffer pod 310a is transferred from the buffer area B to the exchange area E, and the transfer pod 310b is transferred from the exchange area E to the waiting area S.

Accordingly, the buffer pod 310a is prepared to receive the second pallet P2 from the processing machine 100, and the transfer pod 310b coupled to the first pallet P1 from the waiting area S It prepares to discharge the processed workpiece (P) to the transport deck (D).

Referring to FIG. 6L, the processed workpiece P is separated from the first pallet P1 located in the waiting area S and supplied to the empty transport deck D.

When the workpiece take-out signal is applied by the numerical controller 120, the processed workpiece P is separated from the first pallet P1 and supplied to the transport deck D by a transport means such as a robot arm. Accordingly, the finished workpiece P is removed from the machining center 1000 and the first pallet P1 is formed as an empty pallet.

When a new workpiece to be processed is supplied by the new transport deck D, a new machining process by the machining center 1000 is performed by the same process described with reference to FIG. 6A.

According to the machining center as described above, a pallet conveyor having a pair of buffer pods and a transfer pod and linearly reciprocating along a pallet table is temporarily stopped at an arbitrary stop position on a rotational trajectory between a horizontal position and a vertical position. It has a loading arm driven by a servo motor so that it can Accordingly, even when machining is performed in the processing machine, the first pallet to which the machined workpiece is coupled may be transferred from the exchange area of the pallet table to the standby area. Therefore, even while machining of the workpiece to be processed is performed, the operation efficiency of the machining center can be remarkably improved by transferring the machined workpiece to the waiting area and performing the workpiece exchange.

Although the above has been described with reference to the embodiments of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention described in the claims below. You will understand that you can.

Claims (15)

a processing machine including a rectangular housing having a length and width and performing machining on a workpiece by means of a numerical controller;
a pallet table having an exchange area extending along the longitudinal direction of the housing and adjacent to the gate of the processing machine, and a waiting area and a buffer area positioned symmetrically with respect to the exchange area along the longitudinal direction;
a pallet transporter movably coupled to the pallet table and moving a pallet holding a workpiece while linearly reciprocating between the waiting area and the exchange area and between the exchange area and the buffer area; and
A loading arm disposed on the housing adjacent to the gate and performing pallet exchange between the processing machine and the pallet transfer machine in the exchange area;
The loading arm,
a rectangular body fixed to the housing to enable rotational movement in the longitudinal direction from a side of the gate;
a rotation drive connected to the body and the pallet table to rotate between a horizontal position in which the rear surface of the body faces the upper surface of the pallet table and a vertical position in which the rear surface of the body is parallel to the side surface of the housing;
a pallet grip protruding out of the body in the horizontal position and engaging with the pallet; and
A machining center having a loading power source providing a loading driving force to the rotation driving unit. The method of claim 1, wherein the pallet transporter,
a pallet pod having a buffer pod that selectively accommodates pallets and reciprocates between the exchange area and the buffer area, and a transfer pod that reciprocates between the exchange area and the waiting area;
a linear driving unit for linearly transporting the transfer pod and the buffer pod at the same time; and
A machining center having a feed power source providing a feed driving force to the linear drive unit. The method of claim 2, wherein the linear driving unit includes a rack fixed to the upper surface of the pallet table to extend along the longitudinal direction and a plurality of pinions coupled to the rack and rotating, the buffer pod and the transfer pod. is individually coupled with the pinion and simultaneously linearly transported along the same direction according to the linear movement of the rack. 3. The automatic pallet changer according to claim 2, wherein the transfer power source includes any one of a motor generating driving force by power and a hydraulic pressure generator generating the driving force by hydraulic pressure. delete The machining center according to claim 1, wherein the loading power source includes a servo motor having excellent position control characteristics to temporarily stop the body at an arbitrary stop position on a rotational trajectory connecting the horizontal position and the vertical position. . 7. The method of claim 6, wherein the stop position is such that the empty buffer pod is separated from the buffer pod while being transferred to the buffer area and rotates from the horizontal position to prevent collision with the pallet coupled to the pallet grip. Machining center determined by the anti-collision angle measured along the trajectory. The machining center according to claim 1, wherein in the horizontal position, the body is coupled to the pallet table at a boundary area between the buffer area, the exchange area, and the standby area. The machining center of claim 8, wherein the body includes a pair of rotary boxes disposed on both sides of the gate, and the pallet is coupled to the pallet grip at both ends along the longitudinal direction in the horizontal position. . A buffer pod and a transfer pod are prepared in the exchange area and the waiting area of the pallet table extending along the longitudinal direction on the side of the rectangular processing machine for performing machining, respectively;
coupling a second pallet containing a workpiece to be processed to the transfer pod;
exchanging the first and second pallets in the exchange area by unloading the first pallet on which the processed workpiece is fixed from the processing machine to the buffer pod and loading the second pallet from the transfer pod into the processing machine;
transferring the first pallet from the buffer pod to the transfer pod while machining of the workpiece to be processed is performed in the machine; and
Transferring the transfer pod to which the first pallet is coupled to the waiting area;
Exchanging the first pallet and the second pallet with each other,
combining the first pallet unloaded from the processing machine with the buffer pod;
simultaneously transporting the buffer pod and the transfer pod in a forward direction and positioning them respectively in a buffer area and the exchange area located symmetrically with the standby area with respect to the exchange area along the longitudinal direction; and
Separate the second pallet from the transfer pod and load it into the processing machine;
The unloading of the first pallet and the loading of the second pallet are carried out in a horizontal position positioned horizontally on the pallet table at the boundary between the waiting area, the exchange area and the buffer area and vertically parallel to the side of the processing machine. An automatic pallet exchange method performed by rotation of a loading arm performed between vertically positioned positions. delete delete 11. The method of claim 10, wherein transferring the first pallet from the buffer pod to the transfer pod comprises:
simultaneously transporting the buffer pod and the transfer pod in a backward direction and placing them in the exchange area and the waiting area, respectively;
separating the first pallet from the buffer pod by moving the loading arm to the horizontal position;
moving the first pallet to a stop position by rotating the loading arm by an anti-collision angle from the horizontal position along a rotational trajectory connecting the horizontal position and the vertical position;
transferring the buffer pod and the transfer pod, which are empty pods, in a forward direction to position the buffer pod and the transfer pod in the buffer area and the exchange area, respectively; and
The automatic pallet changing method of coupling the first pallet to the transfer pod by moving the loading arm from the stop position to the horizontal position. 14. The method of claim 13, wherein the buffer pod and the transfer pod are coupled to a pair of pinions coupled to a rack fixed to the pallet table and transported simultaneously along the longitudinal direction. The automatic pallet changing method according to claim 13, wherein the rotation of the loading arm is performed by a servomotor having sufficient position control precision to stop at a stop position corresponding to the size of the workpiece to be processed or the finished workpiece.

Images