JPS6099541A - Automatic tool exchanger for machining center - Google Patents

Abstract

PURPOSE:To facilitate the exchange of tools, by enabling the separate motion of tool magazines disposed on two levels, and by enabling a tool exchange arm to be turned by 180 deg. and be moved in the direction of the axis of the turning and in a direction perpendicular to the former direction. CONSTITUTION:An upper and a lower magazines 12, 14, in which tools T are housed, are separately rotated around a bearing guide 20 on the top of a frame 19. An arm shaft unit 32 under the piston rod 30 of a fluid pressure unit 28 can be moved up and down. The arm shaft 50 of the unit 32 can be rotated by 180 deg. around the axis of the shaft and be moved in the axial direction. As a result, a tool exchange arm 54 provided at one end of the arm shaft 50 can be turned by 180 deg. and be moved in the direction of the axis of the turning (the axis of the arm shaft 50) or the direction of attachment and detachment of the tools in the axial direction of the piston rod 30. The tools T can thus be moved to the spindle 80 of a machine tool.

Description

DETAILED DESCRIPTION OF THE INVENTION [Background of the Invention] This invention relates to a machining center, and more particularly to an automatic tool changer for a machining center having a multilayered tool magazine.

More specifically, the present invention relates to an improvement in an automatic tool changing device for an NC machine tool that automatically processes workpieces that require various operations such as milling, drilling, and thread cutting.

In recent years, machining centers have seen remarkable advances in automatic conveyance devices for workpieces and abnormality monitoring devices for machining, while control devices have become highly automated due to the spread of numerical control devices with automatic programming. At the same time, the reliability during processing is extremely high.
Unmanned operation for long periods of time is now possible.

In addition, with the diversification of products, equipment that can be adapted to various processing operations, that is, so-called FM
S (F 1exible lyl anuractu
ring3 system) is now in the spotlight.

It is desirable to accommodate a large number of tools in the tool magazine of an automatic tool changer (ATC). What's more, there is a system in which these are arranged in two stages.

By the way, in a conventional tool magazine that stores tools arranged in two stages, we will explain this by arranging them in two stages, upper and lower, as an example. When trying to take out a tool placed on one of the tiers using the
Tools or tool pots arranged on the other tier are in the path of the spindle or arm and obstruct access to the desired tool.

Therefore, in order to avoid the above-mentioned problems, remove one or two tool pots or tools from the lower magazine on the side where the exchange mechanism must pass, for example, to create a vacant space, and use the side where the exchange mechanism must pass. It is a passage for the main shaft or arm to pass through. This ultimately reduces the number of tools that can be accommodated in the tool magazine.

In order to avoid this, some tools have been designed to increase the distance between the tools stored in the tool magazine, but this requires sacrificing the number of tools that can be stored.

In machining centers, it is important to accurately select the necessary tools according to the machining process.In general, a sequential method is used in which the necessary tools are inserted into a magazine according to the order of machining sequences, and a unique identification method is used in the tool pot. A fixed address system in which the tools are arranged at the positions of their respective identification symbols as written on the program sheet, or the tool itself has some form of identification with the code number. There are also random methods.

In consideration of the arrangement of tools and the degree of freedom of selection, the present invention employs a fixed address system.

[Object of the invention] In view of the above-mentioned matters, the present invention arranges tools in two stages in a magazine, uses a fixed address method,
After removing and using a tool with a unique identification symbol,
J to the machining center that returns to the original identification position.
3. Particularly, it is an object of the present invention to provide an automatic tool changer having the maximum tool accommodating capacity without leaving a tool pot in a portion that serves as a path for a tool change arm as a vacant space.

A further object of the invention is to provide a structure in which the approach movement of the tool changing arm relative to the tool stored in the magazine is linear, without requiring any special movement of the tool or the tool pot. An object of the present invention is to provide an automatic tool changer for a machining center that is easy to use.

[Description of the Invention] In order to facilitate understanding of the above-mentioned objects of the present invention and the many benefits associated therewith, a preferred embodiment of the automatic tool changer for a machining center of the present invention will be illustrated with reference to the accompanying drawings. Explain in detail.

FIG. 1 shows a case where an automatic tool changer 10 of the present invention is applied to a horizontal machining center, and the dople, saddle, etc. are omitted to simplify the explanation.

The automatic tool changer 10 includes a lower magazine 12 that accommodates a plurality of tools T, and an upper magazine 14. Second
As shown in the figure, the magazines 12, 14 are disk-shaped, but they can also be chain-shaped or other types of magazines.

Magazine 12.14 is attached to frame 1 fixed to column 1G.
8 is mounted on the upper part of the bearing guide 13 so as to be rotatable about the bearing guide device 20. Makazin 12.14
The rotation is effected by a servomotor or a suitable prime mover 22 being actuated in accordance with pre-programmed commands via a suitable power transmission mechanism 24 such as gears and pinions.

The frame 18 is stepped with a fluid pressure device U28 disposed in such a way that a piston 26 slides therein.
The Iζ piston rod 30 attached to the tool change arm is fixed to the tool change arm shaft device 32, and the shaft 32
move vertically.

Associated with the fluid pressure device 28 is a fluid pressure device 34 for magazine selection. The piston 3G of this fluid pressure device 34 is connected to the magazine 12.1 via a piston rod 38.
4, and according to the selective movement of the piston 36 in the -L vertical direction,
The lower magazine 12 or the upper magazine 14 is rotated.

A plurality of tool pots 40, 42 are provided on the outer periphery of each magazine 12, 14, respectively. Tool box l-40
, 42 accommodates a tool lower, which is fixed in its position by means known per se, for example a locking pin 46 cooperating with a piston 44, so that its fixation can be released if necessary. It is.

With the configuration described above, among the various tools T loaded at predetermined addresses of the tool pots 40 or 42 of the lower magazine 12 or the upper magazine 14, the tool at the address to be used for machining is placed on the spindle. It can be moved to a position on the mounting side, for example, to the side facing the workpiece W (not shown in FIG. 1).

As mentioned above, the tool exchange arm shaft device 3 is configured to move in the vertical direction by the operation of the fluid pressure device 28.
2 includes an exchange arm shaft 50 and a guide member 52. A tool changing arm 54 is attached to the end of the changing arm shaft 50 on the side facing the workpiece W.

The tool change arm @50 is FM mounted within the guide member 52 so that it can be rotated within the guide member 52 by a suitable motor 56, power transmission 58, or the like. Furthermore, the tool change arm shaft 50 is adapted to cooperate with a fluid pressure device 6o comprising a piston 58 mounted on the guide member 52 so as to be able to slide within the guide member 52 in the direction of its longitudinal axis. be.

The tool change arm 54, which is attached to the shaft 50 so as to be able to rotate and slide together with the tool change arm shaft 50, normally extends upward and downward, as shown in FIGS. 1 and 3. At both ends thereof, grip devices G1 and 02 for gripping the tool are provided, respectively.

Since the tool gripping devices ftf G1 and 02 have the same structure, only one of them, '3Jc100G+' will be explained. A pair of finger members 64 each pivotally connected to the exchange arm 54 by a pin 62 for holding a predetermined stem portion of the tool T, and a fluid pressure operated piston for opening and closing the outer ends of the finger members 64. member 66 and spring member 6
It consists of 8.

Hydraulically actuated piston member 66 is actuated by control fluid conveyed through a fluid passageway 70 provided within tool change arm shaft 50 .

The tool changing arm 54 selectively retrieves the under-tool of the indexed tool pot 40.42 in a position facing the workpiece W of the magazine 12.14 and inserts it into the machine tool, as will be explained in more detail below. The tool attached to the main shaft 80 is removed, and the tool is attached to the magazine 12.1.
4 to return to the original address position.

The main shaft 80 is movable in the vertical direction, that is, in the Y-axis direction, from the position shown in FIG. In order to give you the tools
It is designed so that it can be raised to a predetermined position and then waited. The mechanism for this purpose is conventionally known and is not particularly the gist of this invention, so its explanation will be omitted.

[Tool Replacement] Next, the tools 1 installed in the lower magazine 12 and the upper magazine 14 are attached to the spindle 80, or The tool exchange operation for returning the lower part of the tool to the original address position of the tool pot 40, 42 of the lower magazine 12 or the upper magazine 14 will be explained.

(I> First, no tool is attached to the spindle 8063 or the tool exchange arm 54, and a tool (shown as TL in FIG. 4) loaded at a predetermined address in the lower magazine 12 is attached to the spindle 80. This section explains the case in which machining operations are carried out.

(I-1> A command is sent to the magazine selection fluid pressure device 34, the piston 36 descends, the servo motor 22 is driven, and the tool pot 40 at the desired address of the lower magazine 12 is indexed to the exchange position. It will be done.

(I-2) Next, in response to a command to the fluid pressure device 28, the tool change arm shaft device 32 supported by the piston rod 30 is moved upward from the lower reference axis A-A shown in FIG. Moving.

At this time, the pair of finger members 6 at the upper end of the tool exchange arm 54
4 is left open.

When the arm shaft device 32 rises and reaches the position of the axis line B-B where the open finger member 64 at the upper end of the arm can hold the shaft of the tool TL of the magazine 12, the arm shaft device 32 moves upward. , and close the pair of open finger members 64 to grasp the tool TL. At the same time, magazine 12
The lock bin 46 which had fixed the tool TL is released from its fixation, and the tool T can be freely taken out from the tool pot.

(I-3> Then, a command is given to the fluid pressure device 60 of the tool changing arm device 32, and the piston 5B moves the tool changing arm shaft 50 in the longitudinal axis direction toward the workpiece W (hereinafter referred to as "forward movement"). (FIG. 4). Through this operation, the indexed tool L in the lower magazine 12 is taken out from 40 into the tool box 1 of the magazine 12.

(I-4) In this state, a command is given to the fluid pressure device 28 to lower the tool exchange arm shaft device 32,
Position it so that its axis coincides with the lower reference line A-8. Next, a command is given to the motor 50 and the tool change arm 50
Rotate 180 degrees. Therefore, the tool T shown in FIG.
The axis of L is at a position corresponding to line C--C in FIG. In the meantime, the main shaft 80 is raised, and the axis of the main shaft 80 on which the tool is mounted is moved to a position that coincides with the line C1-C.

<l-5) Here, the tool exchange arm shaft 50 is moved backward, and the tool TL held by the finger members 64 is mounted and fixed on the main shaft 80.

In this way, the spindle 80 can perform desired machining on the workpiece W using the tool TL.

Return the tool mounted on the spindle 80 to the original magazine.
In this case, it can be carried out very easily by reversing the order of the operations described above (I-1 to I-5).

(I[) Next, no tool is mounted on the main spindle 80, and a tool (fifth
A case will be described in which a machining tool (indicated by reference numeral TU in the figure) is moved to an index position and mounted on the main spindle 80, and a machining operation is performed.

(II-1) In this case, the tool TL mounted on the lower magazine 12 becomes an obstacle for the tool exchange arm 54 to approach. Therefore, in the automatic tool changer 10 of the present invention,
The tools TL in the lower magazine 12 that are a hindrance are removed from the tool boxes 1 to 1 and moved to the positions described in the previous section <I-4>. In other words, + of the tool TL in the lower magazine 12
The line m is brought to a lower position where it coincides with the axis C--C in FIG. In this case, the main shaft 80 is located below the line EE at the top of the processing area.

Next, the tool exchange arm 54 is moved back. Since the main shaft 80 is not raised, the tool TL remains gripped by the lower side of the arm 54, and the other finger member 64 of the tool changing arm 54, which is not gripping the tool, is moved upward. ing.

(II-2) Then, the arm 54 is moved upward while leaving the finger member 64 on the side that does not grip the tool in an open state. When the arm 54 rises and reaches the position of the axis D-D where the finger member 64 can hold the shaft of the tool T U of the upper magazine 14, its upward movement is stopped.
Then, the tool TU is gripped in the same manner as described in the section (I-2) above.

(II-3) Then, the tool exchange arm 54 is advanced (FIG. 5).

(II-4> In the state d3 shown in Fig. 5, move the tool changing arm 54 downward to a position where the axis of the tool T L coincides with the axis 1!C-C of Fig. 4) When the tool exchange arm axis 50 reaches 180 degrees, the positions of the tools TU and TL gripped by the tool exchange arm 54 in FIG. 5 are reversed, and the tool TU is on the axis C-C.

(n-5> Therefore, while keeping the tool exchange arm 54 in its forward position, move the tool exchange arm shaft 50 upward, and align the axis of the tool T attached to the upper end of the arm 54 with the lower magazine. The position is brought to match the central axis line B-B of the 12 tool bots 40.

(II-6) Next, by retracting the tool exchange arm shaft 50, the tool T attached to the upper end of the arm 54 is removed.
L can be returned to the tool bot 40 at its original address.

<ll-7) Next, the exchange arm shaft 32 is lowered to a position where its central axis coincides with the line A-A, and then the exchange arm shaft 50 is advanced again. Then, the shaft 50 moves forward while the tool TU is held at the lower end of the exchange arm 54. This corresponds to the situation described in <l-4) above. Meanwhile, raise the main shaft 80 and align its axis aC.
=C to the position corresponding to -.

(n-8>) Then, the tool exchange arm shaft 50 is moved backward, and the tool TU held by the finger member 64 is held by the main shaft 80 for use in machining.

(m) Thirdly, the tool T U to be returned to the upper magazine 14 is mounted on the main spindle 80 and used, and is moved to the tool box 42 at a predetermined address in the original upper magazine 14.
Let us explain the case without returning to .

In this case, the tool T stored in the lower magazine 12 is
L gets in the way of the tool TU that should be returned to the upper magazine 14. After tC takes out the tool TL from the lower magazine 12 with the tool exchange arm 54, the tool mounted on the spindle 80 is returned to the tool bot 40 at the original address in the upper magazine 14.

That is, its operation is as follows.

(m-1) Raise the tool exchange arm 54 from the retreated position, and use the upper finger member 64 to remove the tool TL from the lower magazine 12.
grab.

(m-2) Move the tool exchange arm 54 forward and remove the tool T.
Take out L from the lower magazine 12.

(m-3> Lower the tool exchange arm shaft 50 to the position of the reference axis A-A.

(m-4) Retract the tool exchange arm 54.

(m-5> After raising the main shaft 80 on which the tool TU to be returned to the upper magazine 14 is mounted and gripping the tool TU with the lower finger member 64 of the tool exchange arm 54, the tool exchange arm shaft 50 and did not take out the tool TU from the magazine.

(III-6) Rotate the tool exchange arm shaft 50 by 180 degrees and position the tool TU above the tool exchange arm 54.

(m-7> Raise the tool exchange arm 54 to align the axis of the tool T U held by the finger member 64 with the axis D-D of the tool bot 42 in the upper magazine 14.

(I[I-8> Move back the tool exchange arm 54 and put the tool TU back into the original tool pot 4z of the upper magazine 14.

(m-9> Move the tool exchange arm axis 50 again to the reference axis A-
Lower it to position A.

(III-10) Rotate the tool exchange arm 54 by 180 degrees and position the previously held lower tool TL above it.

<ll-11) Move the tool exchange arm 54 forward.

(III-12> Raise the tool exchange arm 54,
The axis of the tool TL held by the finger member 64 is made to coincide with the axis B-8 of the tool pot 40 of the lower magazine 12.

(III-13> Retract the tool exchange arm 54,
Return the tool TL to the original tool pot 40 in the lower magazine 12. - From the above, the desired tools stored in the tool pots 40, 42 of the lower magazine 12 or the upper magazine 14 are indexed in accordance with the preprogrammed order and mounted on the main shaft 80. It will be understood that the tool can be used to perform processing such as cutting of a workpiece, and the used tool can be returned to the original tool pot.

In the automatic tool changer of the present invention, when there is a vacant space in the tool pot 40 of the lower magazine 12, when taking out or returning the tool TU of the upper magazine 14, the tools in the lower magazine 12 are Needless to say, the removal process can be omitted.

Although each tool exchange operation has been explained above,
In fact, it is possible for those skilled in the art to easily perform these operations in a suitable combination, or to partially change the order of the operations without any particular explanation.

[Brief explanation of the drawing]

Fig. 1 is an elevational view partially shown as a cross section to explain the automatic tool changer of the present invention, Fig. 2 is a plan view showing the magazine portion, and Fig. 3 is the same as Fig. 4 and 5, which are partially cutaway side views seen from the side, are schematic diagrams for explaining the tool exchange operation by the apparatus of the present invention. The relationship between the reference numerals in the accompanying drawings and the main components of the device of the present invention is as follows. 10... Automatic tool changer 12... Lower magazine 14... Upper magazine 1G... Column 18... Frame 20... Bearing guide device Z2... Servo motor 32... Tool changing arm Axis device 34...Fluid pressure device for magazine selection 40, 42...
- Tool pot 50... Tool exchange arm shaft 54... Tool exchange arm 64... Finger member 80... Main shaft G1. Gz...Grip device for holding tools - Ding, T
L, TU...Tool Fig. 2 Fig. 4

Claims (1)

[Scope of Claims] 1. In a machining center based on a numerically controlled machine tool, magazines each having a plurality of tool pots and arranged in two stages, and one of the magazines arranged at a desired indexing position. a device for selectively moving the tool change arm toward the magazine; a tool change arm axis device; a device for moving the tool change arm from a predetermined reference axis position toward the magazine; and a longitudinal axis of the tool change arm axis. reciprocating in the direction and centering on the axis 180
An automatic tool changer for a machining center, comprising: a tool changer arm attached to the tool changer arm axis device so as to be rotatable; and grip devices for gripping tools, which are provided at both ends of the tool changer arm. . 2. The automatic tool changer according to claim 1, wherein the magazine is disc-shaped, and a plurality of tool pots are arranged on the peripheral edge of the magazine. 3. The automatic tool changer according to claims 1 and 2, wherein the magazines are arranged in two stages, upper and lower.