JPH0392238A - Tool exchange arm for machine tool - Google Patents

Abstract

PURPOSE:To simplify exchange tool gripping and opening operation by making each of two finger pairs, provided on a tool exchange arm, pivotal around an axis line parallel to an arm axis line, and making one side finger of the finger pair pivotal in an opening direction against an energizing means by the action of a rotation cam. CONSTITUTION:A cam 51 to which two notch parts 51b are formed is provided to a hollow cam axis 51 independently pivoted in the center hole of a tool exchange arm main body 16. Two sets of a finger pair 17 are pivotally provided around an axis 54 parallel to the cam axis 51 in the arm main body 16, and the passive part 17C of each one side finger FA is pressed by the N direction pivoting of a cam 51a. The finger FA is pivoted in an opening direction against a spring 58, and the other side finger FB too is pivoted in the opening direction. Consequently the gripping of a tool is concurrently released, and the tool is closed by adverse direction pivoting of a cam 51a to be gripped. As a result, the gripping and releasing of the tool can be surely made with simple structure.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a tool changing arm for a machine tool, and more particularly, to a tool changing arm for a machine tool that exchanges tools set in the spindle and tool magazine of the machine tool. .

[Prior Art] Conventionally, machine tools have been known in which tools can be exchanged between the spindle and the tool magazine. With these machine tools]
It has a tool exchange arm for carrying out tool exchange, and a pair of fingers provided on the main body grips the tools set on the spindle and tool magazine respectively, and the tool exchange arm changes the position of the tool and exchanges it. It is something.

This type of tool changing arm uses a link mechanism, for example, by rotating a pinion shaft, the rack member advances and retreats, and a lever that follows this movement moves the rack member forward and backward.
There are those that open and close the gripping claws (Japanese Patent Application Laid-open No. 123646/1986), and those that use a hydraulic cylinder or the like to open and close the front of the gripping claws. [Problems to be Solved by the Invention] However, such a tool exchange arm (1) has problems such as an increase in the number of parts and a complicated configuration due to the link mechanism and hydraulic mechanism. 1 upper with exchange arm 1 upper finger to brake 1 upper finger Since an interlock mechanism is used for the member directly or indirectly connected to the gripping claw 1:.The above disadvantages are exacerbated.Furthermore, a link mechanism is used. (particularly those with many joints in the link) are inherently prone to wobbling at the joints, and as a result, the movement of the fingers may not be accurately regulated. The present invention solves the above problems, has a small number of parts, has a simple configuration, and can move the finger pairs accurately. The purpose of the present invention is to provide a tool changing arm that can regulate the

[Means for solving the problems] Tool changing arm of the present invention] Top Tool changing arm main body 1 capable of turning around one axis: Consisting of a plurality of pairs of fingers that can be opened and closed, the machine tool A tool exchange arm that exchanges a tool set on a main shaft and a tool magazine by using the gripping by the pair of fingers and the rotation of the tool exchange arm main body, the tool exchange arm changing the tool set on the main shaft and tool magazine of the Replacement arm body 1:. A biasing means is mounted rotatably around an axis parallel to the axis and biases each pair of fingers in a direction in which a claw portion at the tip of the pair of fingers closes or opens; A finger driving cam that reciprocates at a constant angle around an axis is provided, and one finger 1 of each pair of fingers: . A passive part is provided that receives the action of the cam and rotates the finger in the opening or closing direction against the biasing force of the biasing means, and the second finger is in contact with the finger having the passive part. The rotation forms an engaging portion that rotates the other finger. [Operation] In the case of the tool changing arm of the present invention having the above configuration, in which the pair of fingers is biased by a biasing means in a direction to close the claw at the tip, when the finger drive cam is rotated by a predetermined angle, One of each pair of fingers (upper passive part receives the movement of the cam and rotates in the opening direction against the urging force. Also, 1: The movement of these fingers is also directly controlled by the other finger by its engaging part. In this way, each pair of fingers is opened by the action of the finger drive cam.At this time, the spindle or a tool from the tool magazine can be inserted between the finger claws.The finger drive cam is rotated in the opposite direction. When the cam is moved, the cam does not act on the passive part, so that each pair of fingers is brought into a closed state by the biasing force of the biasing means.

At this time, if a tool is interposed in advance between each pair of fingers, the tool is gripped.

After gripping a tool, the tool exchange arm is rotated and moved up and down as necessary, allowing the tool gripped by the pair of fingers to be set on the spindle or tool magazine. Next 1: When the finger drive cam is rotated by a predetermined angle in the same manner as above, each pair of fingers opens, and as a result, the tool is released.

On the other hand, among the tool exchange arms of the present invention having the above configuration,
For finger drives that act on the passive part of one finger of each finger pair to close it, in the case where each pair of fingers is biased by a biasing means in the direction of opening the claw at the tip. Provide a cam lf. Performs the same function as above. In this case, the gripping of the tool by the pair of fingers is performed by the finger driving cam, and the release of the tool is performed by the biasing means. [Examples] In order to further clarify the configuration and operation of the present invention described above, preferred embodiments of the tool changing arm of the present invention will be described below.

Fig. 1 (Top) The main part of the swivel arm as an embodiment of the tool changing arm of the present invention is seen from below, and Fig. 2 [The cross section of the second swivel arm in the vertical direction is Fig. 3 +1 This swivel arm The perspective view showing the machining center equipped with
FIG. 4 is a partial sectional view thereof. First, the entire machining center to which the swing arm of this embodiment is mounted will be outlined, mainly with reference to FIG. 3.

As shown in Figure 3, 1:, this machining center
A headstock 3 is supported on a ram 2 which is fixed upright on a base 1. Headstock 3 (guided by near guide 4)
l=Moved in the vertical direction by the Z-axis feed remoter 5 and the feed screw 6. The table 7 provided on the base 1 is movable in the horizontal direction. A spindle motor 8, a spindle 9, and a rotating tool magazine 10 are mounted on the spindle stock 3.

In addition, the main spindle 9 and the tool magazine IOIL JP-A-63-
Since a device similar to that disclosed in No. 123646 is used, its configuration will be briefly explained (Explanation of spindle 9 (see also Figure 4 above). Spindle 91 holds the bottom of the tool removably. A tool magazine 101 is provided with a tool release bin 13 which is connected to the tool attachment part 11 via a drawbar 12 and which releases the tool Tt by being pushed down.The tool magazine 101 holds the tool T in a removable manner. A plurality of holding pots, which are normally in a horizontal position, are provided around the periphery of the rotary disk.Only the holding pot located at the lowest position is rotated 90 degrees downward to take a vertical position. The tool becomes ready to be replaced by the arm A. Selection of the tool T (placement at the lowest position) is carried out by rotation of the upper magazine motor 14.

In addition, a tool changer TC for exchanging tools T between the tool magazine 10 and the spindle 9 is built into the headstock 3.
It consists of a C motor (referred to as C motor) 15, a swing arm A, and the like.

Swivel arm A E of the present embodiment Swivel arm main body 16 and a position 1 symmetrical with respect to its central axis: Two pairs of openable and closable fingers 17 extending outward from the main body 16
The tool T set on the main spindle 9 and the tool magazine 10 is exchanged using the gripping by the pair of fingers 17 and the rotation of the tool exchange arm body 16.

The details of the configuration of the swing arm A will be described later, and the mechanism that causes the movement of the swing arm A within the machining center will be briefly explained.

As a premise, first, the overall configuration of the tool changing device TC will be described using FIG. 5.

Tool change drive shaft (hereinafter referred to as ATC drive shaft) 18 of the present tool change device TC (top) Connected to the ATC motor 15 and arranged facing vertically Rotatably supported on the headstock 3 by bearings 19 and 20 has been done.

The ATC drive shaft 18 has four cams 21, 22,
23 and 24 are provided.

On the other hand, on the side of the ATC drive shaft 18, a hollow main shaft 25, which is provided with a spline 25a at about the lower half and a flange 25b at the lowest end, is arranged vertically. Hollow main shaft 25
(The lower machine frame 2 of the headstock 3 is located near the lower end of the
It penetrates through the hole 26a of No. 6, and by push 27, rotation around the central axis and reciprocating movement along the axis is possible.
Two supported. The upper end of the hollow main shaft 25 (;l.
A through hole 28 made in the upper machine frame 28 of the headstock 3
The upper support member 29 and the pusher 30 are rotatably interposed between the through hole 28a and the hollow main shaft 25. This support member 29 (which is a substantially cylindrical member) is inserted into the lower part 1 of the center hole of the support member 29, and the upper part of the hollow main shaft 25 having a smaller diameter than this hole is inserted. The upper end of the arm center shaft 3, which has a hole diameter slightly smaller than the lower part and passes through the hollow main shaft 25, is fitted and fixed using a key 32 and a bolt 33. Also, the support member An upper gear 29a is carved on the outer periphery of the lower end of the gear 29.
a meshes with the side segment gears 34. A rocker 35 is fixed to this segment gear 34 and is driven by the cam 24.

The hollow main shaft 25 is sandwiched between the inner circumferential surface of the two supporting members and the outer circumferential surface of the arm center shaft 31. Since both are not fixed, they can rotate independently around the axis.

Further, a cylindrical member 36 having a circumferential groove fixed near the vertical center of the hollow main shaft 251 is moved up and down, thereby reciprocating in the vertical direction.

Further 1:. Hollow main shaft 251 and its lower spline 25
It rotates with the rotation around the axis of the spline sub-shaft 37 that surrounds a. The spline subshaft 371 has a follower roller 38 as a follower of the upper and lower surfaces 1 and 21 of the flange 37a formed on the outer circumference 12 of the spline subshaft 371. A swing arm A of this embodiment is fixed to a collar 25b at the lowermost end of the hollow main shaft 25.

Now that the overall structure of the tool changer has been clarified, the movement of the swing arm 8 of this embodiment will be explained in relation to the structure of the four cams 21 to 24 provided on the ATC shaft 18.

Swivel arms All rotate horizontally. This is to exchange the tool T between the upper spindle 9 and the tool magazine 10. The parallel cam 21 installed at the lowest position of the ILATc drive shaft 18 is involved in this movement. Since it is similar to the corresponding part of the device disclosed in Publication No. 63-123646, a brief explanation will be provided (the same applies to the movement by the cams 22 and 23, which will be described later).The parallel cam 21 consists of two plate cams 21a and 21b. It is a composite cam, and is in contact with a follower roller 38 as a follower provided on the spline subshaft 37. Based on this configuration, during one rotation of the ArC drive shaft 18, 1:.spline subshaft 37, The hollow main shaft 25 and the rotating arm A are 180
゜Rotate.

In addition, the rotating arm A moves reciprocally in the axial direction of the hollow spindle 25. This is to extract and clamp the tool T from the headstock 9 and the tool magazine 10. A first cylindrical groove cam 23 formed on the upper circumferential surface of the cylindrical member 39 around the ATC drive shaft 18
It is. A contactor 41 provided at the tip of the swing lever 40 engaged with the first cylindrical grooved cam 23 is connected to the hollow main shaft 25.
It is engaged with the circumferential groove of the outer cylindrical member 36, and during one rotation of the A-C drive shaft 18, the hollow main shaft 25 and the swing arm A fixed thereto are reciprocated once in the axial direction.

Further, the seven finger pairs 17 of the eight rotating arms move to open and close.

The plane groove cam 24 on the upper surface of the cylindrical member 39 surrounding the ATC drive shaft 18 is involved in this movement. Figure 6
A cross-sectional view of the figure is shown. As shown in the figure 1: the groove shape of the planar grooved cam 24 is a closed ring shape, and has a large diameter part 24a, a small diameter part 24b, and a connecting part 24c connecting them, which are circular arcs centered on the cam shaft. have

The oscillator 35 is attached to the large diameter portion 24a of the rotating planar groove cam 24.
, small diameter portion 24b, and connecting portion 24c, the pair of fingers 17 is in a closed state, an open state, or an opening/closing movement state (the detailed movement will be made clear later).

The second cylindrical groove cam 221 formed at the bottom of the outer cylindrical member 390 of the ATC drive shaft functions similarly (see also FIG. 4). A swinging member 421 that swings following the second cylindrical groove cam 22 presses down the tool release pin 13 connected to the drawer of the tool attachment/detachment device of the main shaft 9 and lowers the tool T to the main shaft 9. When is set, it is possible to put it in the detached state.

Detailed structure of the structure of the swing arm A of this embodiment whose movements have been clarified in the above description.The mutual relationship between the above-mentioned movements will be explained in sequence below.

1st @ As shown in Figure 2 1:. The arm body 1619 of the swing arm A is symmetrical to the hollow cam shaft 51 that passes through the center hole and rotates independently of the arm body 16 within the center hole. This arm body 16 is screwed to the collar 25b of the hollow main shaft 25 around the hollow cam shaft 51.

Hollow cam shaft 511 Near the center in the vertical direction, a flange-shaped cam portion 51 extends horizontally and is adjacent to the spacer S.
It is integrally equipped with a. This cam portion 51a{↓ When viewed from below (see Figure 1), it has the shape of a perfect circle with notches at two symmetrical locations. The two cut arrow portions 5lb have the same shape. Note that the tip of the arm center shaft 31 can be fitted into and removed from the hollow hole 12 of the second hollow cam shaft 51 by moving up and down relatively.

On the upper surface of the arm body] 2 sets of 2 through holes 52.
53 (see FIG. 2! l!1) is provided symmetrically with respect to the hollow camshaft 51. Two pairs of fingers 17 having the same configuration are supported by bolts 54 and nuts 55 on the arm body 16 using the through holes 52 and 53 of each pair.

Finger F A iJ of each pair of fingers 17 on the side closer to the central camshaft 51 Cylindrical portion 1 into which the bolt 54 is inserted
7a, a finger main body part 17b extending from there to the outside of the arm body 16 and having a gripping claw G at the tip, a passive part 17c extending from the cylindrical part 17a in a direction substantially opposite to the finger main body part 17b, and these parts. A protrusion 17d protruding substantially perpendicularly to the protrusion 17d is integrally formed with the protrusion 17d. The other finger FB1 is almost symmetrical to the above finger FA.

However, the difference is that the passive corresponding part 17x corresponding to the passive part T7c is slightly smaller than the passive part 17c, and the protrusion 17
A protruding portion (hereinafter referred to as an engaging portion) 17y corresponding to d
lt. ．． The position is somewhat different from that of the protrusion 17d.

A state in which the fingers FA, Fi & are rotatable about an axis parallel to the axis of the hollow camshaft 51 of the swing arm A by being supported by the bolts 54 and nuts 55 1':. In addition, the protruding portion 17d and the engaging portion 17y face each other in the state 1:
, furthermore, the passive part 17c of the finger FA is disposed within the cutout portion 51b.
are arranged. Note that the above support is performed with a pusher 56 interposed between the inner surface of the cylindrical portion 17a and the outer surface of the bolt 54, and a track transfer 57 interposed between the arm body 16 and the upper end surface of the cylindrical portion 17a. There is.

1:. located between the passive portion 17c and the passive corresponding portion 17x of each finger pair 17. A spring 58 is set on the arm body 16 with a spring holder 59.

The spring 581 biases the passive portion 17c and the passive corresponding portion 17x in the opening direction (outward direction).

Therefore, both finger main parts 17bl of the finger pair 17
i It is biased in the closing direction using the fixed cylindrical portion 17a as a fulcrum. However, finger FAI;
L The passive portion 17c contacts the cam portion 51a and is not closed beyond a certain level.

On the other hand, the engaging portion 17y of the finger FB also
Since it engages with the protrusion 17d of A, it is prevented from closing beyond a certain degree.

When the passive part 17c is pressed against the biasing force of the spring 58,
The finger F A I-L rotates in the opening direction using the cylindrical portion 17a as a fulcrum, and the finger FB also rotates in the opening direction with the cylindrical portion 17a as a fulcrum.
is pressed by the protrusion 17d and rotates toward the opening side.

Such opening of the pair of fingers 17 is carried out by the cam part 51a applying a pressing force to the passive part 17b by rotating the cam part 51a at a predetermined angle around the central axis.

Further 1. :． As is clear from FIG. 2, the rotating arm of this embodiment is equipped with a center shaft holder 62, an arm main body holder 63, etc. The lower side of the hollow camshaft 51 has a push 64 in the center hole of the center shaft holder 62 (other side). The cylindrical portion 17a is inserted into the hole of the arm body presser 631, which is connected to the two main bodies 161 of the arm body 161. The drive mechanism (spring 58, etc.) of the finger pair 17 is accommodated in the space surrounded by the fingers FA, F.
A rubber sealing material 65 is arranged to close the gap between the cylindrical portion 17a of B and the hole of the arm body presser 63 through which it is inserted. In this way, the space including the driving portion of the swing arm A is sealed.

Note that the hollow camshaft presser 621L is joined to and supported by the arm body presser 63. In addition, the hollow camshaft presser 62
A disk 66 is joined around the central hole (above).

The details of the movement of the swing arm 8 having the above configuration will be explained together with the movement of other members movable in connection therewith with reference to FIG. 7. Fig. 7 is a timing chart showing the movement of the swing arm 8 by Company 1.

When changing tools, the upper spindle 9 stops at the fixed position,
As soon as this is confirmed, the ATC drive shaft 18 begins to rotate. Note that when the ATC drive shaft 18 rotates, the swing arm A that can move up and down is at the top dead center, and the arm center shaft 31 and the hollow cam shaft 51 of the swing arm A are in a fitted state. It is in.

The cam portion 51a around the outside of the hollow camshaft 51 is
The passive portion 17c of the finger FA is pressed to open the finger FA against the biasing force of the spring 58. Finger F B l friend The engaging part 17y is finger FA
is pressed by the protrusion 17d, so that it is in an open state against the biasing force of the spring 58. In other words, the two pairs of fingers 17 are in an open state. The tool T, which is clamped to the upper spindle 9, is placed between one gripping claw G of the two pairs of fingers 17 in the open state (Jl is placed between the gripping claws G of the other pair of fingers 17). A clamped tool T is interposed. When the ATC drive shaft 18 rotates and reaches a rotation angle of 12 degrees, the oscillator 35 escapes from the small diameter portion 24b of the planar groove cam 24.
It reaches the connecting part 24c and begins to swing. As a result, the segment gear 34, the support member 29, which is driven by the oscillator 35,
The arm center shaft 31 also begins to rotate. In addition, the arm center shaft 31
As the camshaft 51 rotates, the hollow camshaft 51 of the swivel arm A fitted therein also begins to rotate. Then, the hollow camshaft 51
The outer cam portion 51a begins to rotate in the direction of arrow M in FIG. 1, that is, in the direction that does not press finger A.

Therefore 1:. Finger ``A'' begins to close due to the biasing force of spring 58. Finger FBLL
When it is received at 7y, it begins to close under the biasing force of the spring 58 at 12. The ATC drive shaft 18 rotates 500 times, and the oscillator 3
5 reaches the large diameter portion 24a of the planar grooved cam 24, the oscillator 35 enters a stationary state. At that time, the arm center shaft 311
It enters a stationary state after rotating 18 degrees from its initial state. This arm center shaft 31 and 1:. The cam portion 51alt of the hollow camshaft 51 enters a stationary state after 18” rotation,
In this stationary state, no pressing force is applied to the fingers F A l to open them. Therefore, the two pairs of fingers 17 11 are in a closed state with the springs 58 . As a result, they grip the tools Tu of the spindle 9 and the tool magazine 10, respectively.

1 while the finger pair 17 changes from the open state to the closed state.
:． To be precise, when the ATC drive shaft 18 rotates 25 degrees,
Due to the action of the second cylindrical groove cam 22, the tool release pin 13
starts to fall. And the ATC drive shaft 18 is 75″
When rotated, the spindle 9 is completely released from the tool T (unclamped state).

While the tool T changes from the clamped state to the unclamped state 1
:． To be exact, when the ATC drive shaft 18 rotates 65 @1
:, the swing arm A begins to descend by the first cylindrical groove cam 23. And the rotating arm Al. t. When the ATC drive shaft 18 rotates 125 degrees, 1:. Reach bottom dead center. Note that when the ATC drive shaft 18 is around 100@, the arm center shaft 3
1 and the hollow camshaft 51 of the swing arm 8 are separated. While the swing arm A reaches from the top dead center to the bottom dead center 1:. The tool T is pulled out from the tool magazine 10 and detached. Also
Meanwhile 1:, exactly It, ATC drive shaft 18 is 100”
When rotated, the swing arm A begins to swing due to the action of the parallel cam 21 and the like.

Then, the turning ends when the ATC drive shaft 1.8 rotates 280@. Due to this movement, the positions of the two tools T set on the spindle 9 and the tool magazine 10 are exchanged.

During the rotation of the rotation arm 8, precisely l; LATC drive shaft 18
When the ATC drive shaft 18 has rotated 235 degrees, the swing arm A starts to rise from the bottom dead center. Then, when the ATC drive shaft 18 has rotated 295 degrees, it reaches the top dead center.

At this time, the tool T is inserted into the tool magazine 10 and is clamped. On the other hand, a tool is inserted into the main shaft 9, but it is not yet clamped.

Note that when the ATC drive shaft 18 is around 270'', the arm center shaft 31 and the hollow cam shaft 51 of the swing arm A are fitted and assembled.

While the swing arm 8 advances from the top dead center to the top dead center 12: 1:. When the accurate 12IIIATc drive shaft 18 rotates 285', the release pin 1 is released by the action of the second cylindrical groove cam 22.
3 begins to rise. And the ATC drive shaft 18 is 335
'When rotated, the release bin 13 returns to its initial position and the tool T is completely clamped to the spindle 9.

While the tool bottom is being clamped from the unclamped state to the main shaft 9 (12), more precisely when the ATC drive shaft 18 rotates 310 degrees, the oscillator 35 disengages the large diameter portion 24a of the flat grooved cam 24, and the connecting portion 24c and begins to swing again.

This causes the arm center shaft 31 to rotate as described above (;ll.
．． Start rotating in the opposite direction. The arm center shaft 310 rotates (2), so the hollow cam shaft 51 of the rotating arm 8 which is fitted into the arm also begins to rotate in the opposite direction. The finger starts rotating in the N direction, that is, in the direction of pressing the passive part 17c of finger A.

Therefore, {mi finger FA begins to open. Finger F
B also transfers its movement to the engaging portion 17y via the protrusion 17d.
Accept it and start opening. Therefore, two pairs of fingers 17
opens. When the ATC drive shaft 18 rotates 348 degrees and the oscillator 35 reaches the small diameter portion 24b of the planar groove cam 24, the oscillator 35 enters a stationary state. At that time, the arm center shaft 311 returns to the same stationary state as the initial state. Together with the second arm center shaft 31, the outer cam portion 51a of the hollow cam shaft 51 also returns to its initial resting state, and presses the passive portion 17c of the finger FA.
The engaging portion 17y receives the movement of the finger FA and becomes open. As a result, the tool T between the finger pair 17 (the main shaft 9 and the tool magazine 10) is separated.The swing arm A of this embodiment described above has the following advantages.

In the rotating arm A of this embodiment (upper finger pair 1711
When receiving the biasing force of the spring 58, one of the fingers FA receives a direct force from the cam portion 51b for disengaging the fingers by the passive portion 17c, and the other finger receives the force from the finger FB. It is opened and closed by being directly received by the portion 17y. In other words, the opening/closing force of the finger pair 17 is received without any wobbling parts or intervening force transmitting members such as levers, so the movement is accurately regulated and the fingers open/close without any delay in operation. Therefore, the bottom of the tool can be gripped in an accurate posture reliably and quickly, and as a result, there is no possibility of failure in gripping the tool T, and the bottom of the tool can be reliably and quickly attached to and removed from the main shaft 9.

Furthermore, there is no need to use a complicated mechanism such as a hydraulic mechanism or an interlock mechanism, and the configuration is simple.

In addition, since the spring 58 is used to grip the tool T, tools T of various sizes can be easily gripped, and even if an external force is applied to the tool T, the spring 58 acts as a buffer. There is very little risk that the finger pair 17 will function and be damaged.

Furthermore, the space surrounding the driving portion of the pair of fingers 17 is covered from above by the first arm body 16, and is also shielded from the outside by using the first arm body presser 63, rubber sealing material 65, etc. Therefore, there is no risk that the machining debris will become entangled with the drive part during machining by the tool T1 attached to the main spindle 9, and the movement of the drive part will not be hindered.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments. For example, a spring may be provided between each pair of fingers in the direction in which the claws at the tips thereof open, and a cam for driving the fingers may be provided. Of course, the present invention can be implemented in various ways without departing from the spirit of the present invention, such as a configuration in which the finger pairs are moved in the closing direction by acting on the passive portion.

[Effects of the Invention] As detailed above, the tool changing arm of the present invention has the following advantages:
? The pair of fingers can be opened and closed by the cam and the engaging portions that come into contact with each other, and the force for opening and closing the fingers is directly transmitted without going through parts that may cause wobbling. , the opening and closing movements of the fingers are precisely defined. And the movement is swift. Therefore, the tool can always be held in an accurate posture, reliably and quickly. As a result, there is no failure in gripping the tool, and the tool can be reliably and quickly attached to and detached from the spindle or the tool magazine. Furthermore, there is no need to use complicated mechanisms such as hydraulic link mechanisms or interlock mechanisms, and the configuration is simple and the number of parts can be reduced. This 1
This makes manufacturing easier and reduces costs.

[Brief explanation of drawings]

Figure 1 (1) shows the main part of this rotating arm viewed from below. Figure 2 (1) shows a vertical cross-section of the rotating arm as an embodiment of the tool changing arm of the present invention. Figure 3 (1) upper shows this rotating arm. A perspective view showing the installed machining center
Figure 4 is a partial cross-section of the same, and Figure 5 is a partial cross-section showing the configuration of the tool changer.
Figure 7 is a timing chart showing the movement of the swing arm.

Claims (1)

[Claims] 1. A tool changing arm body capable of rotating around one axis,
It is equipped with a plurality of pairs of fingers that can be opened and closed, and is used to hold tools set in the machine tool's main shaft and tool magazine.
A tool changing arm for a machine tool in which tool changing is performed using gripping by the pair of fingers and rotation of a tool changing arm main body, wherein each of the finger pairs is attached to the tool changing arm main body parallel to the axis. A biasing means is attached to each pair of fingers so as to be rotatable around an axis, and biasing means is attached to each pair of fingers to bias the claws at the tips of the pair of fingers in a direction to close or open, A finger driving cam that rotates back and forth in an angle is provided, and one finger of each pair of fingers receives the action of the cam and rotates in the direction of opening or closing the finger against the biasing force of the biasing means. A replacement tool arm for a machine tool, wherein the other finger is provided with an engaging part that contacts the finger having the passive part and rotates the other finger by rotation thereof. .