JP3045756B2 - Machine tool pallet changer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool pallet changing device for transferring a pallet on which a work is mounted between a stacker crane provided in a three-dimensional automatic warehouse and a machine tool such as a machining center. About.

2. Description of the Related Art Machine tools such as machining centers and NC lathes are installed in a three-dimensional automatic warehouse consisting of a storage rack having a large number of storage sections and a stacker crane moving along the storage rack in order to achieve unmanned machining. Various combined machining automation systems have been developed.

In such a machining automation system, it is necessary to efficiently transfer an unprocessed work pallet and a processed work pallet between a stacker crane and a machine tool in order to increase the operation rate of the machine tool.

Problems to be Solved by the Invention Various pallet changing devices for machine tools that transfer the pallets have been proposed (for example, see Japanese Patent Publication Nos. 2-7781, 2-7782 and 2-32104). In addition, there are problems such as those having advantages and disadvantages, those having a complicated structure, those requiring complicated and complicated pallet exchange operations, and those having a problem in the positioning accuracy at the exchange position, and few of them are sufficiently satisfactory.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pallet changing device for a machine tool, which has a relatively simple structure and can transfer pallets extremely efficiently.

Means for Solving the Problems In order to achieve the above object, a pallet changing device of the present invention is provided with a rotary pallet changing device in front of a machining station which is a working position of a machine tool, and further a stacker in front of the turning pallet changing device. A pallet truck is provided that can move in the left-right direction parallel to the traveling direction of the crane. The pallet truck is provided with two setup stations, and one of the setup stations on which the unprocessed work pallets are placed is the revolving type pallet. When facing the pallet changer,
The pallet changing device transfers an unprocessed work pallet and a processed work pallet between the setup station and the processing station, and then the pallet truck moves laterally to a predetermined position, and then the stacker crane becomes empty. After moving to the other set-up station and supplying the unprocessed work pallet, it moves to the one set-up station and receives and discharges the processed work pallet transferred to the one set-up station. It is characterized by having such a configuration.

In a preferred embodiment, the stacker crane is configured to move to the two setup stations and transfer the pallets in a standby state in which the pallet truck stops at a substantially middle position of the moving range. .

In another preferred embodiment, a pallet support is fixedly provided at a position facing the revolving pallet changing device within a movement range of the pallet cart, and an unprocessed work pallet mounted on the pallet support is provided. And the processed work pallet of the processing station are transferred by the revolving pallet changing device, and when the pallet truck moves to one moving end, one of the setup stations aligns with the pallet support table, and Transfer the processed work pallet mounted on the support to the one setup station, and then move the stacker crane to the other available setup station to supply the unprocessed work pallet, When the pallet truck moves to the other moving end, the other setup station moves to the pallet Transfer the unprocessed work pallet placed on the setup station to the pallet support, and then the stacker crane moves to the one setup station, and It is configured to receive and discharge the processed work pallet transferred to the setup station.

According to the configuration described above, when the rotary pallet changer exchanges pallets between the machining station and one of the setup stations, the pallet is not placed on the other setup station. Nothing interferes with the turning operation of the device. Further, when the pallet truck having the processed work pallets mounted on one of the setup stations is stopped at a predetermined position, the supply of the unprocessed work pallets and the delivery of the processed work pallets are performed by the stacker crane. At this time, the stacker crane can supply and discharge the pallets only by slightly moving along the pallet truck.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 3 show a pallet changing device according to the present invention, wherein 1 is a main body of a machine tool such as a machining center, 2
Is a spindle, and a machining table 3 is provided in front of the spindle 2 to form a machining station which is a working position for machining. The processing table 3 includes a clamp mechanism (not shown), and as shown in FIG. 2, can reciprocate in the X-axis direction along guide rails 5, 5 provided on the base 4.

Reference numeral 6 denotes a revolving pallet changing device provided in front of the processing table 3. A revolving arm 8 attached to the upper end of the support shaft 7 is rotatable about the support shaft 7 and is vertically movable in the axial direction. The tip 8a of the swing arm 8 engages with an engagement piece 9 projecting from the side of the pallet P to
Is supported by a cantilever structure to perform an exchange operation. The rotating pallet changing device 6
Is disclosed in Japanese Patent Application No. 63-209171 (Japanese Patent Application Laid-Open No. 2-59246).
However, although the details are omitted here, there is an advantage that the turning radius is small and the entire apparatus can be made compact.

Reference numeral 11 denotes a pallet truck provided in front of the revolving pallet changing device 6, and guide rails 13, 1 disposed on a truck base 12.
Two setup stations 15 and 16 are formed by four pillars 14 erected at both ends of the pallet truck 11 so as to be movable in the left-right direction (X-axis direction) along 3. The pallet cart 11 has a piston rod 17a of a hydraulic cylinder 17 fixed to one end thereof and a cart base 12
The hydraulic cylinder 18 and the piston rod 18a of the hydraulic cylinder 18 are interlockingly connected via a floating joint 19, and are reciprocated in the left-right direction by the cooperative action of the two hydraulic cylinders 17, 18. It stops at the middle position in the middle. When the pallet cart 11 has moved to the right end or the left end, one of the setup stations 15 or 16 faces the rotary pallet changing device 6.

Reference numeral 21 denotes a stacker crane, and rails 22, 22 laid on the floor adjacent to the pallet truck 11 in parallel with the guide rails 13, 13.
Follow along. As shown in FIG. 9, the stacker crane 21 is provided in a three-dimensional automatic warehouse 23 and has functions of traveling, lifting and lowering, and forking.
Forking is the stacker crane 21 has 2
Supporting the pallet or the like from below with a book fork (claw), transfer of the pallet P between the three-dimensional automatic warehouse 23 and the stacker crane 21 or transfer of the pallet P between the setup stations 15 and 16 and the stacker crane 21 To tell.

The two forks are provided on a pallet mounting portion of the stacker crane 21 so as to be able to advance and retreat in a direction perpendicular to the traveling direction of the stacker crane 21.
When the pallet P is moved from the automatic warehouse 23 to the stacker crane 21 to the stacker crane 21, the fork advances to the lower part of the pallet P placed in the setup stations 15 and 16 or the automatic warehouse 23, and then the stacker crane 21 The pallet P is supported by the fork by slightly raising the pallet 21, and the pallet P is moved to the stacker crane 21 by retreating the fork as it is.

Conversely, from the stacker crane 21 to the setup station 15
When the pallet P is moved to the automatic pallet and the automatic warehouse 23, the fork supporting the pallet P on the stacker crane 21 is advanced onto the pallet mounting portion of the setup stations 15 and 16 and the automatic warehouse 23. Then, by lowering the stacker crane 21 slightly, the pallets P can be placed on the setup stations 15 and 16 and the pallet mounting portion of the automatic three-dimensional warehouse 23. Is in a state where nothing is placed, and it is possible to move to the place where the pallet P to be placed next on the stacker crane 21 is located.
The three-dimensional automatic warehouse 23 is installed in parallel with the machine tool main body 1, and is also installed above the machine tool main body 1, and a large number of three-dimensional automatic warehouses 23 are connected to each other. As described later, the stacker crane 21 takes out the pallets (unprocessed work pallets) P ₀ to which the unprocessed works stored in the large number of storage racks 24 are attached one by one, and After supplying to one of the setup stations 15 or 16, the other setup station 16 or
Pallets fitted with machined workpiece which is placed on the 15 (machined work pallet) P ₂ is discharged outside removed, is adapted to receive the storage rack 24.

Next, a pallet changing operation by the pallet changing device having the above-described configuration will be described with reference to FIG.

Figure 4 a shows a standby state in which the pallet truck 11 is stopped in the intermediate position, the machining table (processing station) 3 pallet P ₁ fitted with a workpiece during processing are located. While processing of the pallet P ₁ workpiece, the stacker crane 21 supplies the unmachined workpiece pallet P ₀ in one setup station 15, it is supported by four supports 14 (Fig. 4 b). Next, the pallet truck 11 moves to the right end, and the setup station 15 stops at a position facing the rotary pallet changing device 6 (FIG. 4c). Processing of the pallet P ₁ work has been completed become a machined workpiece pallet P ₂ during this period. In this state, the pallet changing device 6
There turning operation, the machined workpiece pallet P ₂ and unmachined workpiece pallet P ₀ are exchanged, with the machined work pallet P ₂ is placed on the setup station 15, the pallet P ₀
Is placed on the processing table 3 (FIG. 4d). Unmachined workpiece pallet P ₀ starts processing After clamping the machining table 3 by a not shown clamping mechanism. Subsequently, the pallet truck 11 moves to the left, stops at the intermediate position, and enters a standby state (FIG. 4e).

Thus, the unprocessed work pallet P ₀ on the processing table 3
While machining a workpiece, the stacker crane 21 is Hakobidashi from the storage rack for the next unprocessed workpiece pallet P _0, and supplies the setup station 16 vacant (Fourth
Figure f). Subsequently stacker crane 21 is received machined workpiece pallet P ₂ that are placed on the setup station 15 is housed in the storage rack (Figure 4 g).

Then, the pallet truck 11 is moved to the left, setup station 16 placing the unmachined workpiece pallet p ₀ is stopped while facing the rotary type pallet changer 6 (FIG. 4 h). Pallet on the work table 3 during this time is machining of the workpiece has been completed, has become the machined workpiece pallet P _2.
Pallet exchange device 6 again in this state turning operation, the machined workpiece pallet P ₂ and unmachined workpiece pallet P ₀ is exchanged (Figure 4 i), placing the machined workpiece pallet P ₂ is setup station 16 with the location, the unmachined workpiece pallet P ₀ is placed on the processing table 3. The unmachined workpiece pallet P ₀ starts processing After clamped by not shown clamping mechanism. Subsequently, the pallet truck 11 moves rightward, stops at the intermediate position, and enters a standby state (FIG. 4j).

Hereinafter, repeat the same operation, but unmachined workpiece pallet P ₀ is alternately supplied to the two setup station 15, 16.

FIGS. 5 to 7 show a pallet truck 31 having a structure different from that of the pallet truck 11 in the above-described embodiment, and a pallet changing operation thereof.

The pallet truck 31 has two setup stations 32 and 33 on both the left and right sides, and has a slot 3 extending in the movement direction at the center.
4 are provided. The pallet truck 31 is a trolley base 3
6 is provided so as to be movable in the left-right direction (X-axis direction) along the guide rails 37, 37 provided in 6, and can be moved in the left-right direction by a hydraulic cylinder 38 fixed to a bogie base 36. I have.

On the other hand, the trolley base 36 can be moved up and down by a hydraulic cylinder 40 arranged on a base 39, and the pallet trolley 31
Is configured to be able to move up and down. Further, a support 41 fixed to the center of the base 39 has an opening 42 formed in the carriage base 36.
And projecting upward through the long hole 34 of the pallet truck 31,
A pallet support 43 is formed at the upper end. The pallet support table 43 is located in a movement range of the pallet truck, and is disposed at a replacement position facing the revolving pallet replacement device 6,
As shown in FIG. 6, when the pallet truck 31 is at the lower position, the pallet P is supported. When the pallet truck 31 is at the upper position, as shown in FIG. The pallet truck 31 is separated and supported by the setup station 32 or 33. Note that the pallet truck 31 moves in the left-right direction (X-axis direction) without interfering with the column 41 through the long hole 34.

Next, a pallet changing operation using the pallet truck 31 having the above configuration will be described with reference to FIG. The configuration other than the pallet truck 31 is the same as that shown in the previous embodiment.

8 Figure a pallet truck 31 is moved to the left, and the unmachined workpiece pallet P ₀ to the pallet support 43 in the region which are in the lowered position setup station 33 is placed. On the other hand, the pallet P
Does not exist. Rotary type pallet changer 6 in this state turning operation, the machined workpiece pallet P ₂ on the work table 3 and the unmachined workpiece pallet P ₀ on the support 43 is passed exchanged. The unmachined workpiece pallet P ₀ is for machining After clamping the work table 3 by a not-shown clamping mechanism. After the stacker crane 21 is Hakobidashi from the storage rack for the next unprocessed workpiece pallet P _0, it was fed into the setup station 32 vacant during this time,
The stacker crane 21 moves to a predetermined position on the right side (FIG. 8B). Then the pallet truck 31 is raised, after the machined workpiece pallet P ₂ which is placed on the support 43 and transferred to the setup station 33, the pallet truck as in FIG. 8 c
31 moves to the right end and stops. In this case, the unmachined workpiece pallet P _0, which is placed on the setup station 32 is caused to position aligned on the support base 43. The pallet truck 31 is lowered in a state, unmachined workpiece pallet P ₀ being mounted is transferred to the support 43 to the setup station 32,
Prepare for the next delivery. On the other hand, the machined work pallet P ₂ that are placed on the setup station 33 is discharged by the stacker crane 21 is accommodated in the storage rack.

Subsequently, as shown in FIG. 8d, when the pallet cart 31 is moved to the left end in the lowered state and stopped, the pallet support
Unmachined workpiece pallet P _0, which is placed on the 43 is aligned with the setup station 33, the state shown in FIG. 8 a.

Hereinafter, by repeating the same operation as described above, transfer exchange with the machined workpiece pallet P ₂ is performed sequentially unmachined workpiece pallet P _0.

Effect of the Invention As described above, according to the present invention, since the swiveling type pallet changing device is provided between the pallet truck provided with two setup stations and the machining station of the machine tool, the pallet truck is simply a pallet. It is only necessary to support the device and move it laterally in the left-right direction. The structure is simple and the positioning accuracy can be increased. In addition, when the pallet is transferred by the swiveling type pallet changing device, only the pallet to be changed is placed on the pallet truck, so that there is nothing that interferes with the turning operation of the pallet changing device. This not only has the advantage that the two setup stations on the pallet truck can be provided close to each other, and has the advantage that the pallet truck can be downsized. In addition to the supply of the work pallets, the delivery of the processed work pallets mounted on the other setup station can be performed very efficiently.

[Brief description of the drawings]

FIG. 1 is a front view of a pallet changing apparatus according to the present invention, FIG.
FIG. 3 is a plan view of the same, FIG. 3 is a right side view of the same, FIG. 4 is an explanatory view of a pallet changing operation, FIG. 5 is a plan view showing another example of a pallet truck, and FIG. FIG. 7 is a cross-sectional view along the line -6, FIG. 7 is a cross-sectional view showing the same operating state, FIG. 8 is an explanatory view of a pallet changing operation, and FIG. 9 is a perspective view showing an FMS provided with a pallet changing device according to the present invention. It is. 1 ... machine tool main body, 2 ... spindle 3 ... processing table (processing station) 6 ... revolving pallet changing device 11,13 ... pallet truck 12,36 ... truck base 15,16 and 32,33 ... … Setup station 21… Stacker crane 23… Automatic three-dimensional warehouse 43… Pallet support, P… Pallet P ₀ … Unprocessed work pallet P ₁ … Working pallet P ₂ … Finished work pallet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23Q 7/00 B23Q 41/02

Claims (3)

(57) [Claims] 1. A swiveling pallet changing device is provided in front of a processing station which is a working position of a machine tool, and a pallet truck movable in the left-right direction parallel to a traveling direction of a stacker crane is provided in front of the turning pallet changing device. The pallet truck is provided with two setup stations. When one of the setup stations on which the unprocessed work pallets are placed faces the swiveling pallet changer, the pallet changer causes the setup station and the machining to be performed. Transfer the unworked work pallet and the processed work pallet to and from the station, and then the pallet truck moves laterally to a predetermined position, and then moves to the other setup station where the stacker crane is vacant, After supplying the unworked work pallet, the one set-up station A pallet changing device for a machine tool, wherein the pallet changing device receives the processed work pallet transferred to the one setup station and discharges the processed work pallet. 2. In a standby state in which the pallet truck is stopped at a substantially intermediate position in a moving range of the pallet truck, the stacker crane is moved to the two setup stations to transfer a pallet. The pallet changing device for a machine tool according to claim 1, wherein: 3. A pallet supporter is fixedly located at a position facing the revolving pallet changer within a moving range of the pallet truck, and an unprocessed work pallet placed on the pallet supporter and a work station are provided. While transferring the processed work pallet to the pallet carriage by the revolving pallet exchange device, when the pallet truck has moved to one moving end, one of the setup stations is aligned with the pallet support platform and placed on the pallet support platform. The processed work pallet is transferred to the one set-up station, and then the stacker crane is moved to the vacant other set-up station to supply an unprocessed work pallet, and the pallet truck is The other set-up station aligns with the pallet support , And transfers the unmachined workpiece pallet is placed on the stepped-up station on the pallet support table, subsequently,
2. The stacker crane according to claim 1, wherein the stacker crane moves to the one setup station, and receives and discharges the processed work pallet transferred to the one setup station. 3. Pallet changer for machine tools.