JPH0232362Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a tool changing arm of an automatic tool changing device in a machining center.

[Prior art] A machining center for an NC machine tool accommodates different types of tools in multiple tool pots, rotates to selectively indexed positions depending on the machining process, and uses the tool changing arm of an automatic tool changer. The tool is used to take out a tool from the tool pot and attach it to the spindle to be machined, or, conversely, to return the tool attached to the spindle to its original tool pot.

In this type of machine tool, it is desired that the operation speed is increased more and more, but the tool changing operation takes time in order to ensure the safety of the operation.

In order to speed up this tool changing operation, we have applied for patent application No. 204860 in 1982 for ``Automatic tool changing device for machining center'' (Japanese Patent Application Laid-Open No. 1983-99541).
The tool change arm approaches the tool stored in the magazine in a linear manner, and does not require any special movement of the tool or tool pot to avoid collision between the tool change arm and the tool. Disclosed.

The device described in the above-mentioned publication has shown excellent results in use. However, the tool changing arm used in this device is a mechanism operated by pressure fluid as a means of holding the tool, so the structure is complex and requires careful design and manufacturing. Yes, it is economically disadvantageous.

[Purpose of the invention] Considering the above-mentioned problems, the main purpose of this invention is to provide a tool changing arm that has an extremely simple structure and does not require an actuation mechanism using pressure fluid or the like to hold tools. be.

A further object of this tool exchange arm is to provide a tool exchange arm in which there is no risk of tools falling off due to centrifugal force applied to the tools held during high-speed rotation operation or shock during high-speed startup or stop.

It is also an object of this invention to provide a tool changing arm that is precise in its operation and suitable for high speed operation.

[Structure of the invention] A preferred embodiment of the tool changing arm of this invention will be described in detail with reference to the drawings.

As shown in FIG. 1, the tool changer arm 10 of the present invention is attached to a drive shaft 12 of an automatic tool changer that operates as described below so as to rotate therewith. Below, to simplify the explanation,
Identical components will be described using the same reference numerals.

Tool holding devices 14 and 15 are provided at both ends of the tool exchange arm 10, respectively. Each of the tool holding devices 14, 15 consists of a pair of mutually opposed fixed finger members 16 and movable finger members 18. Since the configurations of the tool holding devices 14 and 15 at both ends are exactly the same, only one tool holding device 14 will be described.

Fixed fingers 16 are secured to arm 10 and extend outwardly from the ends thereof. The movable finger member 18 has a generally L-shaped outward extension and an inward extension 22 extending into a transverse groove 20 formed perpendicularly to the longitudinal axis of the arm 10, as shown in FIG. It consists of. Movable finger member 1
The branching portion between the outwardly extending portion 8 and the inwardly extending portion 22 is mounted so as to be pivotable about the arm 10 by a pivot pin 24. Inwardly extending portion 2 of movable finger member 18
One end of a coil spring 26 is attached to the end of the coil spring 2 . Coil spring 26 extends inwardly parallel to the longitudinal axis of arm 10, and its other end is secured to arm 10 by any suitable known means.

As is obvious from the above structure, the L-shaped movable finger member 18 is moved by the action of the coil spring 26.
A closed position may be assumed to retain the stem of the tool T between the opposing outward extension of the stationary finger member 16 and the outward extension of the stationary finger member 16 . In order to maintain this closed position and prevent the pair of finger members 16, 18 from opening, and to release the pair of finger members 16, 18 if necessary, a locking device is provided with a movable finger member. It is arranged to cooperate with 18.

The locking device consists of a lever 28 extending along the central longitudinal axis of the arm 10, the inner end of which is connected to the pivot pin 3, as shown in FIGS.
It is attached so that it can rotate about the arm 10 at 0. The outer end of the lever 28 has an inwardly directed hook-shaped projection 32. A coil spring 3 is attached to the lever 28 at a position close to the hook-shaped protrusion 32.
4, and the other end is supported by arm 10.
It is fixed at A column member 38 is formed on the lever 28 between the pivot pin 30 and the attachment portion of the coil spring 34, and extends through an opening 36 provided in the arm 10 and projects from the inner surface of the arm 10.

An inward extension 22 of movable finger member 18 is used to secure movable finger member 18 in the closed position when the pair of fixed finger member 16 and movable finger member 18 are in the closed position as shown in FIG. A recess 40 into which the hook-shaped protrusion 32 of the lever 28 can be inserted is formed in the center of the lever 28 .

As will be described later, when the arm 10 is moved to a position where the pair of finger members 16 and 18 are released from the closed state, a fixed portion ( The pressing member 42 provided on the flange 114) comes into contact with the column member 38 of the lever 28, and the lever 28 is finally pushed into position by the coil spring 34.
The hook-shaped projection 32 of the lever 28 is disengaged from the recess 40 of the inwardly extending portion 22 of the movable finger member 18 by pressing against the force. and a pair of finger members 16 for grasping or removing the tool T;
18 can be opened by vertical relative movement between the arm 10 and the stem of the tool T.

[Operation and effects of the invention] The tool changing arm 10 of this invention can be implemented as the tool changing arm of the automatic tool changing device (FIG. 4) of the earlier application mentioned above. Explain the operation.

As shown in FIG. 4, in the horizontal machining center 100 of the NC machine tool, the tool magazine 1
02 is provided with a large number of tool pots 104,
Different types of tools T are mounted on each of them, indexed according to a predetermined program, rotated to a tool take-out position, and attached/detached by the tool exchange arm 10.

The drive shaft 12 of the tool exchange arm 10 is the column 10
The tool changing arm is mounted so that it can be rotated in a predetermined manner by a shaft actuator 108 extending horizontally with respect to the drive shaft 12, and can be moved in a predetermined direction in the longitudinal axis direction of the drive shaft 12. Tool change arm axis actuator 108 can be moved vertically relative to column 106 by a cylinder 112 actuated by fluid pressure device 110.

When the tool change arm axis actuator 108 is in its lowest position, the longitudinal axis of the drive shaft 12 is aligned with the lower reference line A-A and supports the tool change arm 10 extending perpendicularly to said axis A-A. Drive shaft 1
2 is at the most retracted position with respect to the tool change arm axis actuator 108, and the column member 38 of the tool change arm 10 is pressed by the pressing member 42 of the flange 114 fixed to the front end of the tool change arm axis actuator 108. Both tool holding devices 14 and 15, which are comprised of a fixed finger member 16 and a movable finger member 18 at both ends of the tool exchange arm 10, maintain an openable state. At this time, the tool exchange arm 10 is in the state shown in FIG.

As mentioned above, the axis of the drive shaft 12 is line A.
- When in position A, the tool change arm 10
The tool holding device 14 at the upper end of the tool magazine 10
2, and the other, lower end tool holding device 15 is also in a position not related to the spindle 108. However, the center line for holding the tool T consisting of the fixed finger member 16 and the movable finger member 18 of the tool holding device 15 at the lower end is
As will be described later, the main shaft 116 is aligned with the tool mounting axis B-B along which the main shaft 116 is raised to exchange the tool T.

Next, the tool change arm 10 remains in the retracted position, i.e. the tool holding devices 14, 1 at both ends thereof.
5 in the openable position, the drive shaft 12 is raised to a position where its longitudinal axis coincides with the upper axis C--C. Thereby, the center line of the tool holding device 14 at the upper end of the arm 10 for gripping the tool T coincides with the center line D--D of the stem of the tool T loaded in the tool pot 104 of the magazine 102. That is,
A tool holding device 14 at the upper end of the arm 10 inserts the stem of the tool T between the finger members 16 and 18.

Therefore, in order to take out the tool T from the tool pot 104, the drive shaft 12 is advanced by the tool exchange arm shaft actuator 108, and the arm 10 is moved to the position shown by the dashed line in FIG. The column member 38 and the flange 114 of the tool exchange arm shaft actuating device 108 that made the fixed finger members 16 and movable finger members 18 of the tool holding devices 14 and 15 of the arm 10 openable.
Since the contact with the pressing member 42 fixed to is removed,
Both finger members 16 and 18 are locked while holding the tool T. Therefore, in this state, no matter how fast the arm 10 rotates, starts or stops at a high speed, the tool T will not come off from the tool holding devices 14, 15.

Next, the tool change arm shaft actuator 108 is lowered in the above-described state, and the drive shaft 12 reaches the position of the lower reference line A--A. During this time, the main shaft 116
rises to the position of line B-B. And drive shaft 1
2 is rotated 180 degrees in its forward position, and the tool T
The tool holding device 14 of the arm 10 that has been taken out moves to the lower end.

In this state, the drive shaft 12 retreats to the inside of the tool exchange arm shaft actuating device 108, and the tool T
The stem of the arm 1 is inserted into the opening of the main shaft 116.
The column member 38 of No. 0 is pressed against the pressing member 42, and the tool holding devices 14, 15 are made openable. Then, when the spindle 116 is lowered to its working position, the tool T is moved to the tool holding device 14. It is separated from the main shaft 116 and held by the main shaft 116.

Above, one tool holding device 14 of the tool changing arm 10 has been explained, but the other tool holding device 15 operates in the same way, takes out the tool T from the tool magazine 102 and mounts it on the main spindle 116, and Take out the tool T from the magazine 102
will be returned to

As is obvious from the configuration and operation described above, the tool changing arm 10 of this invention does not include a fluid pressure device for operating the tool holding devices 14 and 15 inside the arm 0. The structure is simple and easy to manufacture, and even if the arm 10 is rotated at high speed, started or stopped at high speed during tool exchange, there is no danger of the tool T coming off from the arm 10, and safe operation is guaranteed.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a cross section with a part of the tool change arm of this invention cut away, Figs. 2 and 3 are side sectional views to explain the respective operations, and Fig. 4 is a machining center. It is a schematic side view which shows operation|movement in connection with. The main reference numbers in the drawings are listed below. 10... Tool exchange arm, 12...
Drive shaft, 14, 15... Tool holding device, 16...
Fixed finger member, 18... Movable finger member, 24... Pivotal pin, 26... Coil spring, 28... Lever, 32
...Key-shaped protrusion, 38... Pillar member, 42... Pressing member, 100... Machining center, 102...
...Tool magazine, 104...Tool pot, 108
...Tool exchange arm shaft actuator, 114...Fixed flange, 116...Main shaft, T...Tool.

Claims (1)

[Claims for Utility Model Registration] Longitudinal axis of a tool change arm actuating device that maintains a relationship parallel to the longitudinal axis of the spindle of an NC machine tool and a tool magazine to perform a predetermined movement. A tool changing arm fixed to a drive shaft rotatably mounted to perform a predetermined forward and backward movement on an axis so as to rotate and move together with the drive shaft, the tool changing arm having the above-mentioned tools at both ends of the tool changing arm. A fixed finger member fixed to the arm and a movable finger member attached so as to be movable with respect to the arm are provided, and the movable finger member is connected to an outer extension part extending outward from the arm and the outer extension part. and an inwardly extending portion extending perpendicularly to the movable finger member, the inwardly extending portion of the movable finger member being accommodated in a groove formed in a direction perpendicular to the longitudinal axis of the arm, a coil pivotally connected to the arm at a branching portion between an outwardly extending portion and an inwardly extending portion of the movable finger member, and an end portion of the inwardly extending portion of the movable finger member extending parallel to the longitudinal axis of the arm; attached to the arm by a spring, a recess is provided in the inward extension of the movable finger member, one end of a lever extending along the longitudinal axis of the arm is pivotally connected to the arm, and the other end of the lever is attached to the arm by a spring; is a hook-shaped protrusion that can be inserted into the recess, moves the lever in cooperation with the drive shaft, and makes the fixed and movable finger members openable by retraction of the drive shaft and by forward movement. A tool changing arm characterized in that it has a locking device that brings the tool into a closed state.