JPS5939257B2 - automatic tool changer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic tool changer for a machine tool such as a machining center.

Conventionally, tool changing devices for machine tools such as machining centers (hereinafter referred to as machining centers) can be roughly divided into so-called arm-type devices that use a tool changing arm to change tools between a tool magazine and the main spindle of a machining center. There are two types, the so-called armless type, in which tools are exchanged directly between the magazine and the spindle by relative movement between the tool magazine and the spindle without using a tool exchange arm. There were two types, vertical and horizontal, depending on the arrangement of the main shaft that rotates, that is, whether the direction of the axis of the main shaft was vertical or horizontal.

However, the arm type that uses a tool exchange arm,
Regardless of whether it is horizontal or vertical, machining centers require a tool change arm, its ancillary equipment, and space for their installation, which has the disadvantage of making the entire machining center large and complicated. Another drawback was that interference with tools was likely to occur.

Furthermore, in the case of the armless type, for example, in the case of the vertical type, there are two positions: an exchange position where the center of the tool to be used coincides with the center of the spindle, and a standby position where the tool is stored in the tool magazine. Horizontal movement of the entire tool magazine between
Tools are exchanged by vertically moving the spindle head and clamping and unclamping the spindle, but in this case, the shank of the tool stored in the tool magazine is usually exposed and positioned near the spindle. Therefore, it is adversely affected by chips and dust, and since the tool magazine is installed on the table or close to the table, it is likely to interfere with the workpiece, and the range of motion and therefore the machining range are restricted. there were.

On the other hand, in the armless horizontal type, tools are arranged in a matrix in a tool magazine placed on a table adjacent to the workpiece, as shown in Japanese Patent Publication No. 38-10091, for example. Storing and changing tools are performed by aligning the spindle center with the center of the next tool in the tool magazine by positioning the spindle head and table, and by moving in the axis direction of the spindle. Because this is done in between, it is susceptible to the adverse effects of chips and dust as in the case of a vertical type, and it is also necessary to increase the size of the table to accommodate the tool magazine and increase the amount of movement accordingly. There was a drawback.

This invention was made in view of the above-mentioned drawbacks of the conventional device, and uses movement control axes of the table, spindle head, etc. on the machining center, without using a tool change arm, to move the tool magazine from the machining position. It can be installed separately from the main body of the machining center to protect the tools from chips and dust, and there are no restrictions on the installation location of the tool magazine. It is an object of the present invention to provide an automatic tool changer that can also be used to change tools with respect to a tool spindle of an attachment that has a tool spindle oriented in a direction different from that of the main spindle of a machining center.

In order to achieve the above object, the automatic tool changer of the present invention includes a spindle head that is movable by supporting a rotating spindle in which a tool is fitted, and a table that is movable by placing a workpiece thereon. In a numerically controlled machine tool, tools are automatically transferred between the main spindle and a tool magazine that is arranged at a distance from the machine tool body, stores a plurality of tools in respective holders, and is rotatably indexable. The tool exchange device comprises: a tool holder having one or more pairs of gripping claws capable of gripping the required tools; and a tool exchange position of the tool magazine and a predetermined movement position of the table. a movable carrier; a first clamp member provided on the carrier for clamping the tool holder; and a second clamp member provided on the table for clamping the tool holder; The present invention is characterized in that the tool holder is delivered and received by mutual movement and positioning with a table, and new and old tools are exchanged via gripping claws of the tool holder by mutual positioning of the table and the spindle.

Hereinafter, the present invention will be described in detail based on the illustrated embodiment.

As shown in FIG. 1, a machine body 10 of a horizontal machining center equipped with an automatic tool changer according to the present invention has a tool magazine 30 installed separately. 40, and an attachment conveyance/exchange device 60 separately.

As shown in FIGS. 1 and 2, the machine body 10 has a bed 11.
It has a column 12 that is movably provided above, and a spindle head 13 that is mounted on the column so that it can move up and down.
The main shaft 14 is supported so as to be rotatable and capable of being stopped at a fixed angle position (orientation).

Further, an attachment 15 is detachably attached to the tip of the spindle head 13, and the attachment 15 rotatably supports an attachment spindle 16.
is arranged vertically and is connected to the spindle 14 for rotation and orientation of the tool.

17 is a servo motor for feeding the column 12, 18 is a servo motor for vertically feeding the spindle head 13, 19 is a C servo motor for rotating and orienting the spindle 14, and 21 is a servo motor for feeding the spindle 14. be.

The sliding table 22 is fixed to the floor and extends horizontally and at an appropriate length in a direction perpendicular to the axis of the main spindle 14, and the workpiece W is placed on the guide surface of the sliding table 22. The table 23 is moved by a feeding servo motor 24.

The tool magazine 30 is located separately from the machine tool main body 10, and has a plurality of tool holders (sockets) 31 formed around the periphery of the drum. Each tool holder 31 stores the required tools 32. The shank portion 33 is fitted and held, and the magazine 30 is vertically suspended downward, and the entire magazine 30 is configured to be rotatably indexable.

It moves between the above-mentioned tool magazine 30, which is separately installed near the end of the slide table 22, and the main shaft 14 of the machine body 10,
The tool transport and exchange device 40 that transports and exchanges old and new tools is
As shown in FIGS. 1 to 3, a base 41 that also serves as the base of the tool magazine 30 and extends parallel to the slide base 22 to the end of the slide base 22, The track 42 laid, the motor 44 and the feed screw 451, the track 42
a moving table 43 that moves horizontally above in parallel with the table 23;
It consists of a carrier 46 that moves horizontally in a direction perpendicular to the moving direction of the moving table 43 by a cylinder 4γ, a first clamp member 48 that is vertically movable provided on the carrier 46, and the like.

A second clamp member 49 is provided below the table 23 on the side surface facing the tool conveyance/exchange device 40.
As shown in FIG. 5, each piston 48b is of similar construction to the first clamping member 48 and is hydraulically actuated.

When the clamp pieces 48a, 49a moving at 49b are not engaged with the tool holder 51, the recess 48c of the 7-lunge
, 49c, and the clamp piece 48a.

This prevents chips and the like from getting on 49a.

Note that the clamp member 49 shown in FIG.
b reciprocates in the horizontal direction, but the first clamp member 48 differs only in that its piston 48b reciprocates in the vertical direction.

As shown in FIGS. 6A and 6B, the tool holder 51
A first clamp groove 52 that engages with the clamp member 48 of the movable table 43 is formed in the lower part, a second clamp groove 53 that engages with the second clamp member 49 is formed in the back surface, and a A pair of gripping claws 54a, 5 for gripping tools are provided in a horizontal plane parallel to the moving direction with a required spacing between them.
Two sets of 4b are installed.

Each of the gripping claws 54a and 54b is configured as a pair of gripping claws with a fixed claw and a movable claw that is always pressed in the closing direction by a spring 54c, so that the gripping part 34 of the tool 32 is mechanically grasped. It has become.

54a is a positioning key member that secures the angular position of the tool during transportation.

As shown in FIGS. 1, 2, and 4, the attachment conveyance/exchange device 60 is connected to an attachment storage 61 installed at the rear of the machine body 10 (on the opposite side to the table 23, on the right side in FIG. 1). It reciprocates between the spindle 14 and the attachment 15 to carry and exchange it, and the base 62, which passes under the spindle head 13 and extends between the spindle 14 and the attachment storage 61, and the It consists of a track 63 laid in the longitudinal direction on the stand 62, a carrier 64, etc. that moves horizontally on the track 63 to transport the attachment 15 from the attachment storage 61 to the main shaft 14.

Note that the attachment transport and exchange device 60 automatically transports only the attachment 15, and
The attachment and detachment of the spindle head 13 of No. 5 to the front surface can be performed manually, or it can be automatically attached and detached using a known automatic attachment exchange means.

As described above, in the embodiments shown in FIGS. 1 to 6B, the machining center is a horizontal type with a horizontal spindle, but the attachment 15 having the vertical attachment spindle 16 is attached to the tip of the spindle head 13. The automatic tool changer is configured to use the attachment main shaft 16, which has a tool fitting hole directed downward in the vertical direction, for tool change.

The operation of this embodiment will be explained below.

When machining with the current tool fitted to the attachment spindle 16 is completed and a command to select a new tool to be used next and to replace it is issued, for example, from a numerical control device (not shown), the servo motor 19 causes the attachment Main shaft 1
6 is rotated and stopped at a predetermined angular position via the main shaft 14 of the machine body 10, and at the same time, the tool magazine 30 performs an indexing and positioning operation, and the new tool to be used next is placed at the exchange position P shown in FIG. position.

At this time, the gripping claw 54b for gripping the new tool 32 is
Since it is at the same height as the gripping part 34 of the new tool 32, which is elevated by C from the position shown in FIG. 3, and is located at the exchange position Q shown in FIG. The fluid pressure cylinder 47 is operated to move the carrier 46 forward by a distance toward the tool magazine 30 until it reaches point P, and the new tool 32 is gripped by the gripping claws 54b.

When the gripping claw 54b grips the new tool 32, the gripping claw 54b is lowered by a distance C via the tool holder 51 due to the downward movement of the first clamp member 48, and the new tool 32 is held in the tool magazine 30. The cylinder 47 is then moved backward to move the carrier 46 into the tool magazine 30.
(the state shown in Figure 3).

Subsequently, the movable table 43 is fixed on the track 42 of the base 41 by the motor 44 and the feed screw 45, and is moved to a predetermined position R at the end of the sliding table 22 on the tool magazine 30 side.

After the machining with the current tool is completed, the table 23 is moved on the slide table 22 by one drive control of the feed servo motor 24, and is positioned at a predetermined position R point at the end of the slide table 22 on the tool magazine 30 side. , the clamp piece 49a of the second clamp member 49 protrudes and is on standby in a state capable of engaging with the second clamp groove 53 of the tool holder 51.

Therefore, when the moving table 43 moves to the predetermined position R point at the end of the sliding table 22, the clamp piece 4 of the second crank member 49
9a and the second clamp groove 53 of the tool holder 51 engage with each other.

In this state, the clamp piece 49a is retracted by the fluid pressure operated piston 49b, the tool holder 51 is clamped to the side surface of the table 23 by the second clamp member 49, the clamping action of the first clamp member 48 is released, and the clamp piece 48a and the first clamp groove 52 of the tool holder 51 are disengaged.

Next, when the table 23 moves toward the machine body 10 again, the tool holder 51 is disengaged from the first clamp member 48, so it separates from the carrier 46, completes machining, and removes the attachment. The empty gripping claw 54a for gripping the old tool 32' fitted on the spindle 16 and the gripping claw 54b holding the new tool 32 are moved to the front of the spindle head 13, and the empty gripping claw 54a is moved to the front of the spindle head 13. Position the center at the tool exchange position S point.

When the gripping claws 54a are positioned at the 8 points, the column 12 of the machine moves forward on the bed 11 toward the table 23 by the feed servo motor 17, and the center of the attachment main shaft 16 of the attachment 15 moves until it reaches the 8 points. .

At this time, the servo motor 18 for vertical feeding of the spindle head 13 and the servo motor Since the positioning and angle positioning (orientation) is carried out by 19, when the attachment spindle 16 reaches the tool exchange position S point I,
The old tool 32' is delivered to the table 23 and is clamped with a spring 54 in the gripping claw 54a on the tool holder 51.
It is reliably and automatically held at a certain angular position by the elastic force of c and the positioning key 54a.

Therefore, the old tool 32' is unclamped within the attachment spindle 16, and the attachment 1 is removed by the spindle head 131.
5 is moved upward, the old tool 32' is pulled out from the attachment main shaft 16.

Next, the table 23 is moved by the feeding servometer 24.
is further moved toward the machine body 10 by a predetermined distance, and with the center of the gripping claws 54b that grips the new tool 32 positioned at 8 points, the attachment main shaft 16 is moved downward again. The shank 33 is fitted into the tip hole of the attachment main shaft 16.

In this state, when the new tool 32 is clamped within the attachment spindle 16 and the attachment 15 is moved backward by horizontal backward movement of the column 12, the new tool 32 is
2 to the attachment main shaft 16 is completed.

Subsequently, when the table 23 moves toward the tool magazine 30 again and is positioned at the predetermined end position R point, the first clamp member 4 is inserted into the first clamp groove 52 of the tool holder 51.
8 clamp pieces 48a are engaged.

Here, when the first clamp member 48 is tightened and the tool holder 51 is clamped to the carrier 46,
The second clamp member 49 is released and the table 2
3 to release the tool holder 51.

Next, the tool transport/exchange device 40 stores the old tool 32' in the holder 31 at a predetermined position in the tool magazine 30 in a reverse order of operation to that described above, and the tool exchange operation cycle is completed.

In addition, the above-mentioned embodiment is used as an automatic tool changer exclusively for the vertical tool spindle of an exchangeable attachment, which is separate from the tool change position of the tool to which the main spindle 141 is directly attached. In some cases, it is not necessary to replace the entire heavy attachment, and only the relatively lightweight tool that is to be fitted onto the tool spindle needs to be transported and replaced, reducing the time needed for replacement, and the effect is It's thick.

7 to 10 show an embodiment of the tool changer of the present invention used in a relatively small vertical machining center in which the table moves in two directions. The configuration of the transport exchange device 40 is as follows:
This is the same as the embodiment shown in FIG. 6, but since the machine body 10' is of the so-called table type, the column 12 is fixed on the bed 11, and the sliding base 22 of the table 23 is connected to the feed servo motor together with the table 23. 17 to move on the bed 11.

However, the structure and operation of other parts of the machine body 1σ are
It is basically the same as the machine body 10 in the embodiment shown in FIG.

In FIGS. 1 to 10, equivalent or corresponding members are given the same reference numerals as in FIGS. 1 to 6, so detailed explanations will be omitted.

Therefore, in the embodiment shown in FIGS. 7 to 10, the tool magazine 30 side end of the slide table 22 movably laid on the bed 11 of the machine body 10' is used to place the workpiece W. , a tool holder 51 having gripping claws for gripping old and new tools is placed between the carrier 46 and the table 23 whose horizontal movement is controlled by the feed servo motor 241 in a direction perpendicular to the slide table 22.
This is the predetermined point R for sending and receiving.

In the embodiment shown in FIGS. 1 to 10, no attachment is used, so the old and new tools are held between the two gripping claws 54a and 54b of the tool holder 51 transferred to the table and the vertical machining center 10'. A direct exchange is performed with the main shaft 14.

In a horizontal machining center, when directly replacing the tool on the main spindle 14, the horizontal gripping claws 54a and 54b attached to the tool holder 51 are replaced with the vertical gripping claws. Of course, by simply changing the tool magazine 30 from a vertical type to a horizontal type, tools can be automatically exchanged in the same operating sequence as in the illustrated embodiment.

As described above, according to the present invention, by effectively utilizing the movement control of the moving table of a numerically controlled machine tool,
The tool magazine can be installed away from the machining position, the tools can be protected from the harmful effects of chips and dust, and there are almost no restrictions on the installation location of the tool magazine.

Therefore, the tool changer can be provided at a relatively low cost and can be additionally installed on an existing machine.

It is particularly effective when used as an automatic tool changer for attachment tool spindles.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a machining center equipped with an embodiment of the automatic tool changer of the present invention, Fig. 2 is a front view of the main body of the machining center shown in Fig. 1, and Fig. 3 is an arrow indicated by the arrow in Fig. 1.
A front view of the tool conveyance and exchange device as seen in the direction t, FIG.
5 is a detailed sectional view of the clamp member, 6A is a plan view of the tool holder, 6B is a side view of the tool holder,
7 is a front view of the machine body of a vertical machining center equipped with an embodiment of the automatic tool changer of the present invention, FIG. 8 is a side view of the machine body of FIG. 7, and FIG. 9 is a view of the machine body of FIG. 7 and 8. A plan view showing the tool conveying and changing device part of the machine, FIG.
It is a side view seen in the arrow x direction of the figure. 10, 10'... Machine body, 11...
・Bed, 12...Column, 13...
Spindle head, 14... Main shaft, 15... Attachment, 16... Attachment main shaft, 1
7... Servo motor for column feed, 18...
...Spindle overhead downward feed servo motor, 19...
・Motor for spindle rotation and orientation, 21...
...Spindle feed servo motor, 22...Sliding table, 23...Table, 24...Table feed motor, 30...Tool magazine,
31... Tool holder, 32, 32'...
・New and old tools, 34... Gripping part, 40...
・Tool transport and exchange device, 41...Base, 42...
...Trajectory, 43...Moving platform, 44...
...Motor, 45...Feed screw, 46...
...Carrier, 47...Cylinder, 48...
...first clamp member, 49...second clamp member, 48a, 49a...clamp piece,
48b, 49b... Piston, 51...
- Tool holder, 52...First clamp groove, 5
3...Second clamp groove, 54a, 54b...
...Gripping claw, 54c... Spring, 54d...
...Positioning key, 60...Attachment conveyance/exchange device, 62...Base, 63...
... Orbit, 64 ... Career.

Claims (1)

[Claims] 1. A numerically controlled machine tool equipped with a spindle head that is movable by supporting a rotating spindle with a tool fitted thereon, and a table on which a workpiece is placed and movable with respect to the spindle head,
A device that automatically exchanges tools between the main spindle and a tool magazine that is arranged at a distance from the machine tool body and that stores a plurality of tools in respective holders and that can be rotated and indexed, a tool holder having one or more pairs of gripping claws capable of gripping the tool; a carrier movable between a tool exchange position of the tool magazine and a predetermined movement position of the table; a first clamp member for clamping the tool holder, and a second clamp member provided on the table for clamping the tool holder; 1. An automatic tool changer, characterized in that a new tool and an old tool are exchanged via gripping claws of the tool holder by mutually positioning the table and the main shaft.