JPS6110909Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a workpiece conveyance device for a machine tool having a plurality of spindles.

Conventionally, in machine tools that process workpieces sequentially using multiple spindles, workpiece conveyance involves transferring the workpiece between the chucks of each spindle or transferring the workpiece to or from the spindle chuck. A device is provided that includes a rotating plate having a plurality of arms and a gripping device detachably fixed to the tip of the arm with bolts. By the way, when machining a workpiece that has an eccentric part and a concentric part in sequence using multiple spindle chucks, the conveyance device moves the spindle chuck that processes the eccentric part to a position that is offset from the center of rotation of the spindle by a dimension corresponding to the amount of eccentricity. It is necessary to transfer the workpiece at a position concentric with the rotation center of the main spindle for machining a concentric part. Therefore, each time the transfer device receives a workpiece from one of the spindle chucks and transfers it to the other, the dimension from the center of rotation of the rotating plate to the gripping position of the gripping device must be changed. However, in the above-mentioned conventional technology, the gripping device is fixed to the rotary plate with bolts, so the machine must be stopped during processing and the bolts must be loosened to relocate the gripping device, or the gripping device must be removed. It was necessary to take measures such as replacing it. Therefore, the conventional conveyance device is not suitable for practical use when machining a workpiece having an eccentric portion and a concentric portion.

The present invention was developed in view of the above circumstances, and is intended to be used in a machine tool that processes workpieces with eccentric parts using multiple spindle chucks, by making it possible to automatically move the position of the gripping device relative to the center of rotation. The purpose is to provide a workpiece conveyance device that can be applied.

Next, the present invention will be explained based on drawings showing embodiments thereof. FIG. 1 is a front view showing the vicinity of a headstock 5B placed on a bed 5A of a machine tool to which a workpiece transfer device 1 according to the present invention is applied. In this machine tool, spindle chucks 2 and 3 are provided on a spindle rotatably supported on a headstock 5B, and a workpiece 4 is gripped and rotated by chuck claws 2a and 3a provided on both spindle chucks 2 and 3, respectively. (Fig. 2). The workpiece 4 includes a gripped part 4a that is gripped by the claws 2a and 3a, and a gripped part 4a.
It has an eccentric part 4b on a center line C2 which is eccentric by an eccentric amount e with respect to a center line C1, and a concentric part 4c concentrically with the grasped part 4a. One of the spindle chucks 2 has a center line of rotation C as shown in Fig. 2A.
3 and the gripping center line C4 of the chuck claw 2a are deviated from each other by the eccentricity e of the workpiece 4. Therefore, when the gripped portion 4a of the workpiece 4 is gripped by the claw 2a of the spindle chuck 2, the center line C2 of the eccentric portion 4b of the workpiece 4 is located on the same line as the center line C2 of rotation of the spindle chuck 2. In this state, the outer periphery of the eccentric portion 4b can be machined while rotating the spindle chuck 2. The other spindle chuck 3 is
As shown in FIG. 2, the gripping center line of the chuck claw 3a is on the same line as the rotation center line C5. Therefore, when the gripped portion 4a of the workpiece 4 is gripped by the claw 3a of the spindle chuck 3, the concentric portion 4c of the workpiece 4
The center line C1 of is located on the same line as the center line C5 of rotation of the main shaft 3. In this state, the outer periphery of the concentric portion 4C can be machined while rotating the spindle chuck 3.

Now, the workpiece conveyance device 1 of the present invention applied to a machine tool having such spindle chucks 2 and 3 is as follows:
It is capable of reciprocating rotation with a center line C0 passing through the center of a circular locus A passing through each rotation center line C3, C5 of the spindle chucks 2, 3 and parallel to the axes of both spindle chucks 2, 3, and the center line C0 A rotary shaft 6 is provided on a support base 5C mounted on the bed 5A of the machine tool so as to be able to move forward and backward along the machine tool bed 5A.
and a rotating plate 8 secured to the rotating shaft by a key 7 (see FIG. 4). Therefore, by controlling the rotating shaft 6 by the control device of the machine tool to rotate or move it forward and backward, the rotating plate 8 can perform a predetermined rotation or movement forward and backward. The rotating plate 8 is located at the center line C.
Arm portions 9, 1 extending radially from 0 in an X-shape
0, 11, and 12 (Figure 1). Workpiece gripping means 13, 14, 15, 16 are provided near the respective tips of the arms 9, 10, 11, 12. The mutual positional relationship of the gripping means 13, 14, 15, and 16 is such that when the rotating plate 8 rotates and the gripping means 13 or 15 is located on the radial line connecting the center line C0 and the main shaft 2, the gripping means 14 16 is located on a radial line connecting the center line C0 and the main shaft chuck 3 (dashed line in FIG. 1). Further, when the rotary plate 8 rotates and the gripping means 13 and 15 are located on a line perpendicular to the line connecting the center line C0 and the spindle chuck 2, the gripping means 13 and 16 are used for machining the chucks 3 and 2. Evacuate to a position where it will not interfere with the workpiece or tools being worked on (solid line in Figure 1). Next, the gripping means 14, 16
are chucks in which the gripping center lines C7 and C9 are located on the circular locus A passing through the rotation center lines C3 and C5 of the spindle chucks 2 and 3, respectively. On the other hand, the gripping means 13 and 15 have a structure that will be exemplified later regarding the gripping means 13, so that the gripping center lines C6 and C8 are aligned with the position on the circular locus A and the radial line from that position. The object 4 can be moved between a position where the object 4 is displaced outward by the amount of displacement e. When the spindle chuck 2 stops its rotation, a positioning device (not shown) adjusts the center line C of gripping the chuck claw 2a.
4 is positioned on the radius line of the circular locus A passing through the center line C3 of rotation of the spindle chuck 2 and outside the center line C3. Therefore, gripping means 1
3 or 15 is the rotation center line C3 of the spindle chuck 2
When the center line of the grip is moved outward on the radius line of the circular locus A passing through, the workpiece 4 is transferred on the center line C4 of the grip on the claw 2a of the spindle chuck 2. can be done.

FIG. 3 is a cross-sectional view showing the mechanism of the gripping part in the gripping means 13, and FIG. 4 is a cross-sectional view taken from FIG. A support 17 is attached to the arm part 9,
One end 18a of the screw 18 facing in the radial direction of the circular locus A is rotatably supported on the support 17. Further, a pulse motor 19 controlled by a control device of the machine tool is attached to the support 17, and an output shaft 19a of the pulse motor 19 is secured to one end 18a of the screw 18 with a key 20.
The screw 18 is threaded into the nut 21. The nut 21
is fixedly attached to the bracket 22.
A chuck for the workpiece 4 is provided on the bracket 22, and the chuck illustrated in the drawing has the following structure. That is, bracket 2
Holes 22a and 22b are bored in parallel to the screw 18 in 2. A rack bar 24 is inserted into one hole 22a so as to be movable in the axial direction, and a guide bar 24 is inserted into the hole 22a.
5, and the head 25a of the guide bar 25 is integrally connected to the bracket 22 with a pin 26. A rack bar 27 is inserted into the other hole 22b so as to be movable in the axial direction, and a guide bar 28 is integrally formed at the rear of the rack bar 27. Both guide bars 25 and 28 are fitted into a guide member 29 so as to be freely slidable in the axial direction, and the guide member 29 is fixed to the arm portion 9 of the rotating plate 8. A stand 30 is attached to the bracket 22, a cylinder 31 is attached to the stand 30, and a piston rod 31a of the cylinder 31 is connected to the rear end of the guide bar 28. A pinion 33 is rotatably supported on the bracket 22 between the rack bar 24 and the rack bar 27 by bearings 33a, 33a, and the racks 24a, 27a of the rack bars 24, 27 mesh with the pinion 33 in opposing directions. Both rack bars 24, 27 are connected to claws 36, 37 via adapters 34, 35, respectively.
is installed. Therefore, if the piston rod 31a of the cylinder 31 is moved forward and backward, the claws 36, 3
7 is opened and closed, and the concentric portion 4C of the workpiece 4 can be gripped between the claws 36 and 37. On the other hand, a through hole 3 drilled along the axis of rotation of the pinion 33 shown in FIG.
A shaft 32 is slidably inserted into the shaft 3b.
A flange 32a is formed at one end of 2.

Furthermore, a stepped hole 33 formed in the pinion 33
A spring 32b inserted into the shaft 32b presses the flange 32a of the shaft 32 in a direction away from the pinion 33.

Therefore, one end of the workpiece 4 to be gripped is connected to the shaft 3.
2, when the claws 36 and 37 are opened to transfer the workpiece 4, the workpiece 4 comes into contact with the reference surface of the spindle chuck 2 or 3, and is securely gripped by the spindle chucks 2 and 3. Ru. Further, when the pulse motor 19 receives a control command from the control device of the machine tool and operates to rotate, the screw 18 rotates, and the bracket 22 moves forward and backward.
The center line C6 of the grips 6, 37 can be moved in the radial direction of the rotary plate.

Returning to FIG. 1 again, a shifter device 38 for the workpiece 4 is provided on the top of the support stand 5C. The structure of the shifter device 38 is as follows. That is, a guide rail 39 is attached to the support stand 5C, and the base 40 is moved left and right along the guide rail 39 by power. A pair of levers 41, 4 are attached to the base 40.
1 is pivotally mounted, and claws 42, 42 for the workpiece 4 are attached to one ends of both levers 41, 41. The other ends of both levers 41, 41 are adapted to engage with a piston rod 43a of a cylinder 43 provided on the base 40, and rotate as the piston rod 43a moves up and down. Therefore, when the piston rod 43a of the cylinder 43 is moved forward and backward, the claws 42, 42 open and close, and the gripped portion 4a of the workpiece 4 can be gripped between the claws 42, 42. In addition, the base 40 moves left and right along the guide rail 39 and stops at a predetermined position, thereby moving the grip center line C10 of the claws 42, 42 between a first position and a second position described below. be able to. That is, the center line C
10 indicates a circular trajectory A of the gripping means 15 when the rotating plate 8 is rotated as shown by the chain line in FIG.
It can have a first position co-linear with the upwardly retracted gripping center line C8 and a second position co-linear with the gripping center line C9 of the gripping means 16.

When the rotating plate 8 rotates as shown by the solid line in FIG. 1 and the gripping means 13 and 16 are retracted from the spindle chucks 3 and 2, the insert 44 is placed in a position where the workpiece 4 can be supplied to the gripping means 13. An outshoot 45 is also provided at a position where the workpiece 4 can be retrieved from the gripping means 16. Furthermore, workpiece 4
In order to be able to process a workpiece 46 that does not have an eccentric part, unlike the above, an insert 47 is provided at a position where the workpiece 46 can be fed to the gripping means 14 when the rotary plate 8 is in the same state as described above. By providing the outshoot 48 at a position where the workpiece 46 can be recovered from the means 15, the versatility of machining by a machine tool using the workpiece conveyance device 1 can be increased.

Next, a conveying means for continuously machining the workpiece 4 using a machine tool to which the workpiece conveyance device 1 is applied will be explained. The transport procedure repeats the following first to third states. Note that when the rotating plate 8 rotates in order to transition from each state to the next state, the rotating plate 8 first moves forward along the center line C0, then rotates by a predetermined angle, and then moves forward along the center line C0. By retreating along C0, the rotating plate 8 is prevented from interfering with each part of the machine tool or the conveying device. It has been omitted.

In the first state of the conveying means, the rotating plate 8 is
It is located at the position shown by the solid line in the figure.
The jaws 2a of the spindle chuck 3 grip the workpiece 4 (hereinafter referred to as the "primary processed product") after the machining of the eccentric portion 4b in the chuck 2.
After the machining of the eccentric portion 4b is completed, the spindle chuck 3
The workpiece 4 (hereinafter referred to as the "finished product") after the machining of the concentric portion 4C has been completed is held at the first position by the shifter device 38. The shifter device 38 holds another primary processed product at the second position (chain line in FIG. 1). The holding means 16 provided on the rotating plate 8 holds another finished product. In this state, the workpiece 4, which is the raw material, is transferred from the insulator 44 to the holding means 13, and the holding means 16
The finished product is delivered from the conveyor 40 to the outshoot 45. Next, when the rotating plate 8 rotates 90 degrees clockwise in FIG.

In this state, from the shifter device 38 to the gripping means 14
In addition to delivering the primary processed product to
The primary processed product is delivered from the claw 2a of the spindle chuck 3 to the gripping means 15, and the finished product is delivered from the claw 3a of the spindle chuck 3 to the gripping means 16. Next, while the gripping means 15 moves so as to displace its gripping center line C8 in a direction approaching the rotational center line C0 by the eccentricity e of the workpiece 4, the rotating plate 8 moves in the opposite direction in FIG. When the shifter device 38 is rotated 180 degrees clockwise and moved to the first position (solid line in FIG. 1), the third state of the conveyance procedure is entered.

In this state, the material is delivered from the gripping means 13 to the pawl 2a of the spindle chuck 2, the primary processed product is delivered from the gripping means 14 to the pawl 3a of the spindle chuck 3, and the primary processed product is received from the gripping means 15 to the shifter device 38. hand over. Next, while the gripping means 15 moves to displace its gripping center line C8 away from the rotation center line C0 by the eccentricity e of the workpiece 4, the rotating plate 8 moves as shown in FIG. Then, the shifter device 38 is rotated 90 degrees clockwise, and the shifter device 38 is moved to the second position. Furthermore, the workpieces are machined in the spindle chucks 2 and 3, respectively. When processing is finished,
The rotation of the spindle chucks 2 and 3 stops. As described above, the main shaft chuck 2 stops at a position where the gripping center line C4 of the claw 2a is deviated outward on the radial line of the circular locus A. Since the transport procedure returns to the first state in this manner, the same procedure as described above can be repeated thereafter.

The workpiece conveyance device of the present invention automatically moves in the radial direction of the rotation of the gripping means by a control command issued from a control device or by switching operation of a switch while continuously machining a workpiece with a machine tool. , it is possible to accurately position both eccentric chucks and non-eccentric chucks provided on a plurality of main spindles of a machine tool. Furthermore, when machining workpieces with different eccentricities, the amount of movement of the gripping means can be changed, and in addition to workpieces with eccentricities, normal workpieces without eccentricities can also be machined.
In this way, the present invention is highly practical and enables versatile processing.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a front view, FIG. 2 is a side view, FIG. 3 is a sectional view of the vicinity of the gripping means, and FIG. 5 is an enlarged sectional view of FIG. 4. 1... Workpiece conveyance device, 2, 3... Spindle chuck, 4... Workpiece, 8... Rotating plate, 13, 14,
15, 16...gripping means, 19...pulse motor.

Claims (1)

[Scope of utility model registration request] In a machine tool that is equipped with a plurality of spindles and has a spindle chuck that is attached to the plurality of spindles and grips a workpiece, and in a conveyance device that conveys the workpiece between the plurality of spindles, a rotating shaft of a conveying device provided on the rotating shaft; a rotating member fixed to the rotating shaft that rotates in a direction crossing a plurality of spindle axes and having a plurality of arm portions; and a rotating member provided on the arm portion of the rotating member that is Comprised of a gripping means for gripping an object, and a position setting means provided between the gripping means and the arm portion and moving the gripping means in a radial direction perpendicular to the rotation axis and the main axis to set an arbitrary position, The position setting means matches the distance from the rotation axis to the spindle axis and the distance from the rotation axis to the machining center of the workpiece gripped by the gripping means, and the workpiece is moved between the gripping means and the spindle chuck. A workpiece transfer device for a machine tool, which is characterized by transferring a workpiece between machines.