JPH0565307B2 - - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a workpiece magazine for mounting a large number of workpieces and continuously supplying the workpieces or tools to an index table or the like of a machine tool such as a machining center.

[0002]

[Prior Art] Generally, special robot hand devices, chains, etc. are used to automatically feed workpieces to machine tools such as N/C milling machines and machining centers. They are equipped with new dedicated control devices and equipment that are separate from the control system, and the equipment costs are also very high.

[0003] In contrast to the above-mentioned expensive dedicated equipment, machining is performed by making maximum use of the movement of the moving table of the machine tool and the vertical movement of the machine spindle, that is, the control system already provided in the machine tool. Continuous supply of materials can save costs for new and expensive equipment.

[0004] In view of this, in Japanese Patent Application No. 60-135755, the applicant fixed a workpiece magazine loaded with a plurality of workpieces to a moving table of a machine tool, and only the control system of the machine tool We are currently developing a system that can supply multiple workpieces continuously.

[0005] However, since the area of the movable table and its movement range are limited, the fixed circular workpiece magazine as disclosed in Japanese Patent Application No. 60-135755 has a significant limitation in terms of the workpiece loading capacity.

[0006]

OBJECTS OF THE INVENTION It is an object of the present invention to significantly increase the workpiece loading capacity of a workpiece magazine.

[0007]

[Means for Solving the Problems] In order to solve the above problems, the present invention fixes one end of a magazine body onto which a large number of workpieces can be attached on a moving table of a machine tool, and moves the other end. Extend it outside the table and attach the auxiliary legs to the magazine body extension.
It is characterized by the workpiece magazine being movable together with the movable table.

[0008]

[Embodiment] In Fig. 2, a machining center is rotatably equipped with a vertical machine main shaft 1 for mounting tools, an index table 5 is fixed on a movable table 2 of the machining center, and a workpiece magazine 3 is mounted. Fixed. The machining center is controlled by an N/C (numerical control) device, and the moving table 2 is operated to move back and forth and left and right. A workpiece holder 6 is attached to the machine main shaft 1.
A robot hand 7 for grasping the robot hand 7 is detachably inserted and fixed. The robot hand 7 has an annular V-groove (grip portion) 8 for an ATC (automatic tool change) device, and can be freely replaced with a tool in a tool magazine by a manipulator of the ATC device. That is, it is fitted and held onto the machine main shaft 1 only when the workpiece W is being replaced and transported. The index table 5 has a rotating shaft 2
0, a stepping motor 22, a cylinder device 33 for attaching and detaching the holder, and the like. Rotating shaft 20
A central hole 71 for mounting a workpiece holder is formed in the holder.

[0009] Each workpiece W is fixed to a workpiece holder 6 via a jig 14, and the workpiece holder 6
is fixed in the recess 21a of the cup 21 in the following manner. That is, as shown in FIG. 9, the holder 6 has a handle 6' and a bolt 62 for attachment/detachment.
The enlarged end portion of the cup 21 is locked by a lock pin 64 of the cup 21. Lock pin 64 is spring 65
is biased toward the bolt side. The workpiece holder 6 is also formed with an annular V-groove 66 for gripping by the robot hand 7.

[0010] In FIG. 1 showing a view of the workpiece magazine 3 in the direction of the arrow in FIG. The end portion extends rearward from the movable table 2 and is supported on the floor surface M via the auxiliary legs 10 and rolling wheels 11.
It is also possible to move freely. A drive shaft 25 is rotatably supported at the front end of the magazine body 9, and a drive sprocket 16 is fixed to the drive shaft 25. A driven shaft 24 is rotatably supported at the rear end of the magazine body 9, and a driven sprocket 17 is fixed to the driven shaft 24. Both sprockets 1
A cup chain 23 in which a large number of cups 21 are connected in a chain is stretched between the cups 6 and 17.

[0011] As shown in FIG. 3, a drive wheel (drive disk) 26 and an indexing disk 27 are fixed to the drive shaft 25 on the back side of the magazine body 9.
Both 26 and 27 are adapted to rotate integrally with the drive sprocket 16. A plurality of (for example, eight) drive pins 30 parallel to the drive shaft 25 are fixed to the drive wheel 26 at equal intervals in the circumferential direction as shown in FIG.
The same number of index grooves 28 as the drive pins 30 are formed in the drive pin 30 .

[0012] In order to rotate the drive wheel 26 intermittently, a drive cylinder (for example, a hydraulic cylinder) 31 is fixed to the magazine body 9, and a pin 35 is attached to the rod portion 31a of the drive cylinder 31.
The ratchet plate 3 can be moved up and down at a certain angle through
2 are pivotally connected. The ratchet plate 32 extends near the top of the drive wheel 26 in the direction of arrow F, and has a pinch groove 36 with an open lower end that can freely engage the drive pin 30 at its tip, and a release groove at its tip. A cam surface 37 is formed. Pincer groove 36
is formed to have a width with a slight play in the direction of arrow F with respect to the drive pin 30, and the edge of the pinch groove 36 on the arrow R side is closer to the center of the drive wheel than the edge of the pinch groove 36 on the arrow F side. It has been formed for a long time.

[0013] In order to position and lock the drive wheel 26 at a predetermined position, an air cylinder 42 is disposed opposite to the end surface of the indexing disk 27 on the arrow R side, and the rod portion 42a of the air cylinder 42 is It can freely protrude into the ejection groove 28.

[0014] The operation of both cylinders 31 and 42 is configured to be controlled by a limit switch mechanism including a cam pin 40 and a limit switch 41, and by commands from a controller of a machining center.

[0015] That is, the cam pin 40 is fixed to the magazine body 9, and the cam surface 3 of the ratchet plate 32
7 at a distance in the direction of arrow F. Further, when the cam pin 40 moves the distance of one pitch of the drive pin 30 in the direction of the arrow F, the cam surface 37 comes into contact with the cam pin 40 and the cam pin 40 moves the drive pin 30 one pitch in the direction of the arrow F.
It is placed in a position that pushes up. The limit switch 41 is connected to the ratchet plate 3 as shown in FIG.
When the drive cylinder 31 is pushed up by the cam pin 40, the drive cylinder 31 stops extending and the rod part of the air cylinder 42 is stopped. 42a is configured to protrude. Further, the rod portion 42a of the air cylinder 42 is moved backward and the rod portion 31a of the drive cylinder 31 is moved forward according to a command from the controller of the machining center.

[0016] The auxiliary leg 10 in FIG. 1 is divided into an upper member 10a and a lower member 10b, and a guide rod 46 fixed to the lower member 10b is fitted into an inner peripheral hole of the upper member 10a so as to be movable in the vertical direction. and both members 1
A coil spring 47 is compressed between 0a and 10b. The lower member 10b is urged downward by the coil spring 47, and the rolling wheel 11 is brought into contact with the floor surface M. The rolling wheel 11 has a holder 11a supported by a lower member 10b so as to be rotatable around a vertical axis, and can be turned in all directions.

[0017] In FIG. 7 showing an enlarged sectional view of the index table 5, the handle portion 6' is divided into a cylindrical holder shaft portion 68 and a tapered cone 69. The inner cylindrical surface of the tapered cone 69 is the shaft portion 68
The disc spring 6 is fitted to be movable in the axial direction.
9' in the direction of arrow F', and is locked by a snap spring 70. The rotating shaft 20 of the index table 5 has a center hole taper 71 for mounting a holder, and is integrally fixed to a boss portion 75 with a bolt 73. Boss part 75
is rotatably supported by an index table case 76 via a bearing. The boss portion 75 is equipped with a worm gear (not shown), and the worm gear meshes with a worm screw for index rotation, and the worm screw is interlocked with the stepping motor 22 (FIG. 2) controlled by an N/C device (controller). It is connected.

[0018] A slide tube 8 is provided on the inner circumference of the rotating shaft 20.
1. Lock ball 82 and cylinder device 33
A lock mechanism consisting of (Fig. 2) etc. is connected,
The locking mechanism allows the workpiece holder 6 to be fixed and released.

[0019] The slide cylinder 81 is fitted to the inner circumferential surface of the rotating shaft 20 so as to be movable in the axial direction, and is provided with a plurality of tapered holes 85 at the tip end on the side of the arrow F, and a locking ball is installed in the tapered hole 85. 82 is inserted for radial outward movement. A tapered cam surface 86 is formed on the inner circumferential surface of the rotating shaft 20, and the diameter becomes smaller toward the arrow F' side.
Ball 8 when it comes to the smaller diameter side (arrow F' side) than 6
2 protrudes toward the shaft center and engages with the enlarged portion of the attachment/detachment bolt 62. The slide cylinder 81 is connected to the piston of the cylinder device 33 in FIG. 2 via a connecting bolt 87.

[0020] A positioning and drive key 50 is attached to the rotating shaft 20, and a key 50 is attached to the holder 6.
A key groove 50a into which the key is inserted is formed.

[0021] Next, the operation will be explained. First, a series of operations for exchanging workpieces will be described. A large number of workpiece holders 6 with workpieces W attached thereto are attached to each cup 21 of the workpiece magazine 3 shown in FIG. 1, respectively.

[0022] By moving the movable table 2 back and forth and left and right by the N/C device and by moving the machine main shaft 1 equipped with the robot hand 7 up and down, the holder 6 of the workpiece W located at a portion A on the movable table 2, for example. is gripped by the robot hand 7, carried to the index table 5, and mounted on the rotating shaft 20.

[0023] After the attachment is completed, the robot hand 7 of the machine spindle 1 is replaced with a desired cutting tool in the tool magazine by the automatic tool exchange device, and the tool is rotated by the rotation of the machine spindle 1 to perform cutting, etc. . The holder 6 during cutting is cooled with cutting oil or the like. On the other hand, the index table 5 is operated by a stepping motor 22 in FIG. 2 which is controlled by an N/C device.
By driving the workpiece W, the workpiece W is indexed and rotated to the necessary rotation angle and rotation speed. When the instructed program is completed, a work operation completion signal is transmitted to the N/C device of the machine body.

[0024] After cutting is finished, the robot hand 7 is attached to the main spindle 1 again by the automatic tool changer, and
By moving the movable table 2 back and forth, left and right, and moving the machine spindle 1 up and down, the holder 6 of the workpiece W after machining is grasped and removed from the index table 5, for example, as indicated by the arrow A in FIG. Return to part 21.

[0025] When the workpiece W is returned after cutting,
In response to a command from the controller of the machining center, the rod portion 31a of the drive cylinder 31 shown in FIG. As the drive wheel 26 rotates, the indexing disk 27, drive shaft 25, and drive sprocket 16 shown in FIG. 1 also rotate in the direction of arrow F', moving the next cup 21 to section A.

[0026] When the next cup 21 reaches part A, the cam surface 37 in FIG. At the same time, the limit switch 41 is activated. When the limit switch 41 is operated, the ratchet plate 32 is stopped, the rod portion 42a of the air cylinder 42 projects into the index groove 28, and the drive wheel 26 is locked and held in a fixed position.

[0027] Then, as in the previous case, by moving the movable table 2, etc., the robot hand 7 grabs a new workpiece W (holder 6) in the A section and attaches it to the rotating shaft 20 of the index table 5.

[0028] During the above-described work, when the movable table 2 moves back and forth, left and right, the auxiliary legs 10 move on the floor M together with the movable table 2.

[0029] In addition, due to the exchange of the workpiece W, etc., a weight imbalance of various parts occurs in the coupling chain 23, but for example, the ratchet plate 32 simply
If the structure is such that the weight unbalance mentioned above causes the cutout chain 23 to move from a stopped state to a series of movements of starting, moving, decelerating, and stopping, it will come to a complete stop until the inertial force is attenuated. Otherwise, the stopping position may shift. However, when the drive pin 30 is configured to be driven with the drive pin 30 sandwiched between the pinch grooves 36 of the ratchet plate 32 as shown in FIG. At least, overshoot due to acceleration is prevented within the width range of the pinch groove 36.

[0030] Next, detailed operations when attaching and detaching the workpiece holder 6 to and from the rotating shaft 20 of the index table 5 will be described. When inserting the holder 6 into the index table 5, first the drive key 50 shown in FIG. 7 is inserted, and then the bolt 62 is inserted into the ball 8.
2. At this time, the flange 6a of the holder 6 and the end surface 20a of the rotary shaft 20 of the index table 5 are brought into pressure contact, and at the same time, the taper cone 69 is brought into close contact with the inner circumferential surface of the center hole 71, causing the disk spring 6
9' is compressed to ensure that the tapered cord 69 and the center hole 71 are in close contact with each other.

[0031] Both end surfaces 20a and 6 from when the key 50 is inserted until both end surfaces 20a and 6b come into pressure contact.
Between b and 9, the holder 6 is guided to the key 50, but the key 50 and the key groove 50a of the holder 6 in FIG.
and move in the axial direction, so both of them are 50,50
a has a structure that allows it to move by this moving length.

[0032] Note that when the key 50 is held in the keyway 50a, both end surfaces 20a and 6b in FIG.
When the holder 6 is not pressed yet, the holder 6
Since the taper cone 69, which is the part that aligns the axial centers of the rotary shaft 20 and the rotary shaft 20, has not yet contacted the center hole 71, the workpiece holder 6 is not in contact with the key 50 until the taper cone 69 and the center hole come into contact with each other. and a keyway 50a. Therefore, the axial length of the keyway 50a is longer than the length of the key 50 by the amount of axial movement. Further, when a workpiece W is attached to the workpiece holder 6, when the workpiece W is inserted at an angle due to the weight imbalance due to the weight of the workpiece, the holder 6 is guided by the key 50 and the rotation axis is in the normal position. 20 is inserted.

【0033】

[Another Embodiment] (1) FIG. 6 shows a modification of the auxiliary leg 10, in which the spring force of the coil spring 47 can be adjusted.

[0034] That is, the guide rod 4 of the lower member 10b
6, screw the spring force adjustment nut 50 into
A bottomed cylindrical spring seat 51 is disposed on the upper surface of the spring seat 51, and a coil spring 47 is compressed between the spring seat 51 and the upper member 10a. The guide rod 46 passes upward through the fixing mounting plate 52 at the upper end, and a vertical positioning nut 53 is screwed into the upper end thereof, and the positioning nut 53 abuts against the upper surface of the mounting plate 52. The mounting plate 52 is fixed to the magazine body 9.

According to the auxiliary leg 10 in FIG. 6, by rotating the adjustment nut 50 and changing the vertical position of the spring seat 51, the spring force can be adjusted to match the size and weight of the workpiece magazine. .

[0036]

Effects of the Invention As described above, according to the present invention, the workpiece magazine 3 is fixed on the movable table of the machine tool and is configured to move with the movement of the movable table 2.
The workpieces can be easily and automatically exchanged by moving the machine and moving the machine spindle 1 up and down, and the control system of an existing machine tool (machining center, etc.) can be used extremely effectively for changing the workpieces. Therefore, although a large number of workpieces can be processed continuously and unmanned as described in item 1 above, there is no need to provide a specialized control device for transporting workpieces, and the investment amount can be saved. One end of the magazine body is fixed on the movable table of the machine tool, the other end is extended outside the movable table, and the auxiliary leg 10 is attached to the extended part of the magazine body, so the magazine body itself can be enlarged and the workpiece can be The number of attachments can be increased. 2. The workpiece magazine according to claim 1, further comprising wheels movable in all directions at the lower end of the auxiliary leg.

[Brief explanation of drawings]

FIG. 1 is a left side view (view from the arrow in FIG. 2) of a workpiece magazine to which the present invention is applied.

FIG. 2 is a cross-sectional view of FIG. 1;

FIG. 3 is a cross-sectional view taken from FIG. 1;

FIG. 4 is an enlarged view in the direction of the arrows in FIG. 2;

FIG. 5 is an arrow view of FIG. 2 showing the drive cylinder in an extended state;

FIG. 6 is a sectional view showing a modification of the auxiliary leg.

FIG. 7 is a partially enlarged vertical cross-sectional view of the index table.

FIG. 8 is an enlarged view of FIG. 7 in the direction of the arrows.

FIG. 9 is an enlarged vertical cross-sectional view of the cup.

[Explanation of symbols]

1...Machine spindle 2...Moving table 3...Workpiece magazine 10...Auxiliary leg 11...Wheel.

Claims (2)

[Claims] [Claim 1] One end of the magazine body, on which a large number of workpieces can be freely attached, is fixed on a moving table of a machine tool, the other end is extended outside the moving table, and auxiliary legs are attached to the extension of the magazine body. , a workpiece magazine characterized in that the workpiece magazine is movable together with a movable table. 2. The workpiece magazine according to claim 1, further comprising wheels movable in all directions at the lower ends of the auxiliary legs.