DEVICE FOR SWIVELING, TURNING AND CHANGING WORKPALLETS ON A HORIZONTAL MACHINING CENTER

Description

[0001] The invention relates to a device according to the preamble of patent claim 1.

[0002] In practice, it is common practice to connect two pallets docked back-to-back on the pallet carriers to the horizontal machining center's power supply. However, this connection concept results in the disadvantage that a single pallet cannot be removed, because it is then not supplied with the vacuum needed to secure the workpiece to the pallet during swiveling and turning. This also results in a loss of time during a pallet change cycle.

[0003] In a device known from DE 10 2017 217 878 ​​A1 for pivoting, turning and changing workpiece pallets on a horizontal machining center, said device has two spaced-apart pivot arms which can be pivoted synchronously and parallel to one another about a pivot axis, each of which has a pallet carrier which can be turned about a turning axis parallel to the pivot axis for the selective docking and undocking of at least one pallet.

[0004] The invention is based on the object of improving a device of the type mentioned at the outset in such a way that even a single pallet can be removed from or inserted into the horizontal machining center without endangering its vacuum supply.

[0005] The stated problem is solved with the features of claim 1.

[0006] Since the supply of the respective pallet during swiveling and turning does not come from the horizontal machining center, but rather via the power supply interface attached to the pallet carrier, the vacuum supply is guaranteed even when picking up, swiveling, turning, and removing a single pallet. Other working media and signals for operating the pallet carrier can also be continuously transmitted via the interface. The pallet carrier equipped with the power supply interface enables the continuous supply of working media, even during the turning and swiveling movements, to even just one pallet independently of the machining center during pallet changes, independently of the machining center. At the very least, it can be supplied with vacuum to secure at least one workpiece to the setup side of the pallet.

[0007] The interface is conveniently located on a carrier plate connected to the pallet carrier, preferably on the outer side of the pallet carrier facing the swivel arm, and extending from the pallet carrier to the free end of the swivel arm. The interface is stably supported and easily accessible at all times as it moves with the pallet carrier relative to the swivel arm.

[0008] The carrier plate is sturdy and bolted to the pallet carrier for easy installation. It can have a curved profile.

[0009] The interface expediently has several connections, at least for vacuum and / or pneumatics and / or hydraulics and / or electrical or optical signals and / or power, etc. These working media and the signals are used to operate the pallet carrier and, if necessary, to monitor a docked or attached pallet.

[0010] To allow the interface to move with the pallet carrier, it is connected to the stationary power supply via a flexible and movable supply line duct, supported, for example, on the swivel arm. Various lines and cables are protected within the supply line duct, preventing them from colliding with the pallet(s), the swivel arm, and the pallet carrier.

[0011] The interface connections can be connected to inlets located on or in the pallet carrier via fixed or loose connecting cables, preferably with quick couplings.

[0012] For example, a vacuum inlet on the pallet carrier is connected to one of at least two vacuum bells pneumatically extendable from and retractable into the pallet carrier, preferably each vacuum bell being selectively activatable or deactivatable via a valve. The valve allows the vacuum bell interacting with a specific pallet to be activated, while in the absence of a second pallet, the corresponding vacuum bell remains deactivated to prevent a loss of vacuum. The vacuum required for workpiece clamping is reliably transmitted through the respective vacuum bell via large cross-sections with high throughput as soon as the vacuum bell is in a tight seal with the pallet.

[0013] Furthermore, a hydraulic inlet on the pallet carrier can be connected to a pair of hydraulic cylinders per pallet level of the pallet carrier, which can be used to dock or undock the respective pallet in one of two pallet levels via extendable and retractable rams. Thus, the device can handle two pallets simultaneously, then back to back, or a single pallet at a time in each of the two pallet levels of the pallet carrier.

[0014] Furthermore, an electrical and / or optical inlet on the pallet carrier can be connected to at least one signal transmitter arranged on the inside of the pallet carrier, preferably an inductive or optical coupler, for example in order to monitor the proper docking and the docking state of the pallet.

[0015] Since a pallet is undocked from the fixture in the processing position in the horizontal machining center, it is advisable for a pallet that is fixed in the processing position in the horizontal machining center and undocked from the pallet carriers to be connectable to at least one adjustable vacuum bell in the horizontal machining center. This vacuum bell in the horizontal machining center then ensures the correct vacuum supply to the pallet.

[0016] The drawing illustrates embodiments of the invention. It shows: Fig. 1 a perspective view of one half of a device for swiveling, turning and changing pallets on a horizontal machining center, Fig. 2 a perspective view of Fig. 1 in a different viewing direction, Fig. 3 a perspective top view, in phantom, of details of the device, and Fig. 4 a perspective view of a section of a horizontal machining center with the pallet fixed in the machining position.

[0017] One in the Fig. 1 bis 3 The device V shown for swiveling, turning and changing workpiece pallets P, a so-called pallet changing automation, is mounted, for example, on the front side of a horizontal machining center H, in which workpieces, for example aircraft parts, are machined, which are positioned on a pallet P during the change and processing with a vacuum. For this purpose, the pallet P has a plurality of suction openings 7 on its setup side 6 facing away from the rear, which are subjected to a vacuum, while in the Fig. 4 In the processing position shown, the pallet P is clamped with at least one workpiece in the horizontal machining center H and is also subjected to vacuum in the processing position.

[0018] The device V has in the Fig. 1 and 2 two swivel arms 1 (only one of which is shown) which, in bearing block cheeks 3 mounted on the horizontal machining center H and optionally supported on the floor, can be swiveled back and forth about a swivel axis 2 approximately parallel to the floor from the shown position near the floor on both sides of a pallet support 8 over approximately 90° into an approximately vertical position. Each swivel arm 1 carries, near the free end of the swivel arm, a block-shaped pallet carrier 4 which can be turned over approximately 180° about a turning axis 5 parallel to the swivel axis 2 and is used to manipulate one or two pallets P which can be docked and undocked on both pallet carriers 4 in two pallet levels.

[0019] Fig. 1 shows the pallet P with its upward-facing setup side 6 and the suction openings 7 arranged therein in a position on the pallet tray 8.

[0020] A stationary power supply 9, for example, which may be part of the horizontal machining center H, provides various working media or signals or electricity used for pallet changing and specifically for operating devices in each pallet carrier 4. These include, for example, vacuum, pneumatics, hydraulics, electrical or optical signals, electric current, and the like.

[0021] In a flexible, oversized cable duct 10, which may be supported on the swivel arm 1 or a housing 40 covering the drive (not shown) for turning the pallet carrier 4 about the turning axis 5 on the swivel arm 4, cables and lines (not shown) are accommodated, which lead to a driver plate 11, 12 mounted, e.g. screwed, on the pallet carrier 4 on its outer side facing the swivel arm 1 and to a power supply interface S arranged there. For example, lines 13 are indicated, which are installed on the, e.g. curved, driver plate 11, 12. The power supply interface S has a plurality of connections 14, which are connected via lines and cables (not shown) to inlets, for example 20 and 39, on and in the pallet carrier 4. The Fig. 1 and 2The visible upper side of the carrier plate 11, 12 can be closed by a cover (not shown) that shields the interface S. Cables from the connections 14 to and into the pallet carrier 4 can be routed through a window of the carrier plate 11, 12.

[0022] In the embodiment shown, the pallet carrier 4 has the two pallet levels defining, attached hydraulic cylinders 16 and 15, each in pairs, with which in Fig. 3 shown punches 24 are hydraulically retractable into open receptacles 17 on a front side 19 of the pallet P in order to dock the pallet P. Furthermore, for example, one pneumatic cylinder 18 per pallet level is mounted on the pallet carrier 4, which is used to adjust Fig. 3 shown vacuum bells 28, 29 (at least one per pallet level) can be applied against vacuum inlets 30, 31 in the front side 19 of the pallet P. Electrical cables (not shown) also run, for example, to signal transmitters 27 arranged on the inside of the pallet carrier 4, e.g. inductive or optocouplers. Suction points 25, 26 belonging to the vacuum bells 28, 29 (at least one per pallet level) are shown in Fig. 2 shown on the inside of the pallet carrier 4.

[0023] According to Fig. 2 At least one suction inlet 22 is also provided on the long side of the pallet P, which is arranged according to Fig. 4 to apply vacuum to the pallet P in the processing position in the horizontal machining center H.

[0024] The swivel arms 1 can also be Fig. 2 be coupled in a rotationally fixed manner about the pivot axis 2 via a main shaft 23.

[0025] In Fig. 2 The rams 24 for the upper pallet level and the rams 24 for the lower pallet level are shown in the extended state. The rams can be extended and retracted in pairs to dock or undock a pallet P in one of the pallet levels.

[0026] According to Fig. 3 The vacuum bells 28 and 29 can be selectively positioned to the suction points 26, 25 by means of the pneumatic cylinders 18. Valves (not shown) are provided to selectively deactivate or activate each vacuum bell 28, 29. The vacuum inlets 30, 31 (at least one per pallet level) are indicated in sections on the front side 19. Furthermore, Fig. 3 a connecting line 38, e.g. with a solenoid valve (not shown), from a vacuum connection 14 of the energy supply interface S to an inlet 39 to the vacuum bell 29.

[0027] When turning the docked pallet P according to Fig. 1 The flexible cable duct 10 unwinds more or less around the turning axis 5 in accordance with the rotation of the pallet carrier 4 relative to the swivel arm 1, so that the pallet carrier 4 or the docked pallet P is permanently supplied with the respective working medium or signals can be given or picked up.

[0028] To transfer the Fig. 1 shown pallet P with a workpiece fixed on the setup side 6 and to change the pallet P in the working position from the horizontal machining center H, the Fig. 1 The docked pallet P is first swivelled upwards by the swivel arms 1 by approximately 45° and then or at the same time turned clockwise so that its rear side facing away from the set-up side 6 is in the processing position according to Fig. 4 in the horizontal machining center. The pallet carriers 4 are then pivoted with the lower, free pallet levels by the pivot arms 1 past the end faces 19 of the pallet P in the machining position and docked to it, so that now both pallets P are positioned back to back in the device. The pallet P in the machining position is released in the horizontal machining center, after which the pivot arms 1 pivot downwards by approximately 45°, both docked pallets are turned, for example, counterclockwise, so that the Fig. 1 The pallet P shown, with its setup side 6 and the workpiece on it, is moved into the machining position in the horizontal machining center, clamped there, and undocked from the pallet carriers 4, while the previously removed pallet P remains docked. The removed pallet P, with the machined or partially machined workpiece, is then lowered by approximately 45° using the swivel arms 1 and rotated around the turning axis 5 so that its setup side faces upwards when it is placed on the pallet support 8 and undocked. During this changeover process, both pallets, or at least each individual pallet, are continuously supplied with vacuum via the energy supply interface S.

[0029] Since the pallet, which has been placed in the horizontal machining center H, clamped there and undocked from the pallet carriers 4, can no longer be supplied with vacuum via the interface S of the pallet carrier 4, the following applies in the horizontal machining center H according to Fig. 4 at least one separate vacuum supply 37 is provided, for example in a cutout 34. Fig. 4 shows the long side of the pallet P with the suction connection 22, which is Fig. 2 is shown, and against which a vacuum bell 36 is applied, for example by means of a pneumatic cylinder 35. Fig. 4 indicates a cutout 32 intended for clamping the pallet P in the machining position of the horizontal machining center H and for machining, in which the pallet P remains clamped with its outwardly facing back side 33 while the workpiece is being machined.

[0030] Conveniently, both pallet carriers 4 of the device V are equipped with a power supply interface S, although it would be sufficient to equip only one pallet carrier 4 in this way.

Claims

1. Device (V) for swivelling, turning and changing workpiece pallets (P) on a horizontal machining center (H), with two spaced swivel arms (1) that can be swivelled synchronously and parallel to one another about a swivel axis (2), each of which has a pallet carrier (4) that can be turned about a turning axis (5) parallel to the swivel axis (2) for selectively docking and undocking of at least one pallet (P), characterized in that each pallet (P) is connected, at least when turning and swivelling, to an energy supply (9) which also provides a vacuum for fixing a workpiece, and is provided on at least one pallet carrier (4), a connectable power supply interface (S) is provided to move with the pallet carrier (4) upon swivelling the swivel arms (1) and turning the pallet carrier (4), the power supply interface (S) being connected with the energy supply (9) and being linkable with every docked pallet (P).

2. Device according to claim 1, characterized in that the connectable power supply interface (S) is arranged on a driver plate (11, 12) connected with the pallet carrier (4), which driver plate ( 11,12 )is advantageously fixed on an outside of the pallet carrier (4) facing the swivel arm (1), and extends from the pallet carrier (4) to beyond the free end of the swivel arm.

3. Device according to claim 2 , characterized in that the driver plate (11, 12) is screwed to the pallet carrier (4).

4. Device according to at least one of the preceding claims, characterized in that the interface (S) has a plurality of connections (14) for vacuum and / or pneumatics and / or hydraulics and / or electrical or optical signals and / or electric power and the like.

5. Device according to claim 1, characterized in that the power supply interface (S) is connected to the stationary placed energy supply (9) via a flexible and movable supply line duct (10), preferably supported on the swivel arm (1).

6. Device according to claim 4, characterized in that the connections (14) are connectable via permanently or loosely installed connecting lines (38), preferably via quick release couplings, with inlets (39) arranged on or in the pallet carrier (4).

7. Device according to at least one of the preceding claims, characterized in that on the pallet carrier (4), a respective vacuum inlet (39) is connected with one of at least two vacuum bells (28, 29), said vacuum bells being placed in the pallet carrier (4), in such a way that they are pneumatically extendable to a vacuum inlet (30, 31) of the pallet (P) and retractable into the pallet carrier (4), and wherein, preferentially, each vacuum bell (28, 29) is optionally activatable or deactivatable via a valve.

8. Device according to at least one of the preceding claims, characterized in that on the pallet carrier (4), one respective hydraulic inlet (20) is provided on a pair of hydraulic cylinders (45) per pallet level of two pallet levels, by means of which the respective pallet (P) can be docked and undocked in one of the two pallet levels of the pallet carrier (4) via props (24) which are arranged extendably and retractably.

9. Device according to at least one of the preceding claims, characterized in that on the pallet carrier (4), one respective electrical and / or opto-connection (14) of the power supply interface (S) is connected with at least one signal transmitter (27) provided on the inside of the pallet carrier (4), the transmitter preferably being an inductive or optical coupler.

10. Device according to at least one of the preceding claims, characterized in that a pallet (P) fixed in a machining position of the horizontal machining center (H) and undocked from the pallet carrier (4) is connectable with at least one vacuum bell (36) adjustably provided in the horizontal machining center (H).