JP2023116901A - Automatic workpiece conveyor - Google Patents

Abstract

To provide an automatic workpiece conveyor with a robotic hand without limitation in a rotation angle.SOLUTION: An automatic workpiece conveyor includes: a rotatable robot hand provided with a turning part where a chuck device holding and releasing a workpiece by an operation of a gripping claw is mounted, a support part supporting the turning part and a turning motor turning the turning part built in the support part; a control device performing turn control of the robot hand; and a chuck detection device provided with a fixation side transmission coil built in the support part, and a movable side transmission coil built in the turning part transmitting a detection signal of a detection switch not in contact with the fixation side transmission coil and detecting the operation of the gripping claw, and transmitting the detection signal to the control device.SELECTED DRAWING: Figure 3

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic workpiece transfer machine capable of turning a robot hand continuously in the same direction and having no limit on the rotation angle.

A machine tool is provided with an automatic workpiece carrier that receives a workpiece to be machined and transfers a machined workpiece. In the automatic work transfer machine, a robot hand having a chuck device for gripping and releasing a work is rotatably attached to the tip of a robot arm or the like. The automatic workpiece transfer machine described in Patent Document 1 below is configured such that a proximity sensor detects opening and closing of chuck claws of a robot hand and expansion and contraction of a cylinder. The cable of such a proximity sensor passes through a guide hole provided in the casing of the holder, is pulled out from a cable outlet opening at the axial center of the end face of the cylindrical part, passes through the through hole of the support shaft at the tip of the arm, and enters the inside of the arm. is guided by

JP-A-6-134643

However, the conventional automatic work transfer machine uses a proximity sensor to open and close the chuck claws, and since the connected cable is led from the robot hand to the inside of the arm, the robot hand can be rotated freely. can't This is because it is necessary not to apply an excessive load due to twisting so as not to break the cable. Therefore, the turning motion of the robot hand in the conventional automatic work transfer machine is configured to rotate forward and backward within a predetermined rotation angle range. Therefore, in such a conventional structure, for example, it is sufficient to rotate the robot hand forward by 90 degrees to perform the next operation, but it is not possible to do so, and the operation is large, such as the need to rotate it in the reverse direction by 270 degrees. In addition, the control was complicated, such as judging forward rotation and reverse rotation.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an automatic workpiece transfer machine having a robot hand with no limit on the angle of rotation.

An automatic work transfer machine according to the present invention includes a revolving section equipped with a chuck device that grips and releases a work by the action of gripping claws, a support section that supports the revolving section, and a revolving section incorporated in the support section. a rotatable robot hand equipped with a turning motor, a control device for controlling turning of the robot hand, a fixed transmission coil incorporated in the support part, and the fixed transmission coil, which are not in contact with each other, a chuck detector that transmits the detection signal to the control device, the chuck detection device including a movable-side transmission coil incorporated in the revolving portion that transmits a detection signal of a detection switch that detects the operation of the gripping jaws;

According to the above configuration, the robot hand capable of gripping the workpiece by the action of the gripping claws is moved to a predetermined position by the drive mechanism, and the workpiece can be transferred to and from the spindle chuck of the machine tool. In the hand, the revolving part on which the chuck device is mounted is rotatable with respect to the supporting part by the revolving motor. It becomes possible to detect the movement of the gripping claws by means of the detection switch without limiting the angle.

1 is a front view showing a machine tool equipped with an automatic work transfer machine; FIG. 1 is a side view showing an embodiment of an automatic work transfer machine; FIG. It is an image diagram showing a part of the chuck detection device in the automatic work transfer machine. It is the figure which showed the positional relationship of the chuck device provided in the robot hand.

An embodiment of an automatic work transfer machine according to the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a machine tool equipped with an automatic work transfer machine. This machine tool 1 is a front two-spindle lathe, and a supply work stocker 3 is arranged on the left side as viewed from the front, and an inspection device 5 is arranged on the right side. The machine tool 1 is provided with a gantry-type automatic work transfer machine 7 and is configured to transfer the work W from the work stocker 3 to the inspection device 5 via the spindle device of the machine tool 1 .

The work stocker 3 is configured such that stacked works W are respectively mounted on a plurality of pallets, which move circumferentially on a moving table, and the pallets on which the corresponding works W are mounted are sent to the delivery position. . An elevator is provided at the delivery position, and the works W are taken out one by one from the pallet by the automatic work transfer machine 7 . The machine tool 1 incorporates a pair of lathes for performing predetermined machining on the workpiece W transported from the workpiece stocker 3 into the machining chamber. Transfer between the spindle chucks in the machining chamber is also performed by the automatic work transfer machine 7 . The machined workpiece W is transferred from the machine tool 1 to the inspection device 5 by the automatic workpiece transfer machine 7, where the dimensions of the machined portion are measured.

FIG. 2 is a side view showing the automatic work transfer machine 7. As shown in FIG. The automatic work transfer machine 7 is provided with a driving mechanism for moving the work W in three axial directions. The drive mechanism is configured such that a rail member 11 is arranged on the ceiling portion of the machine tool 1 in the width direction of the machine body, and a traveling table 12 moves between the workpiece stocker 3 and the inspection device 5 . The running base 12 is provided with a front-rear slide base that can move in the front-rear direction of the machine body, and an elevating arm 13 erected in the vertical direction with respect to the front-rear slide base is configured to be movable in the vertical direction. A robot hand 15 having two chuck devices 21 and 22 is attached to the lifting arm 13 at its lower end.

The robot hand 15 for transferring the workpiece W has two chuck devices 21 and 22 arranged in orthogonal directions, and has a revolving part 23. The revolving part 23 is a rotating shaft tilted 45 degrees with respect to the vertical direction. By rotating around O, the positions of the chuck devices 21 and 22 are exchanged. In such an automatic work transfer machine 7, the robot hand 15 moves in the machine body width direction of the machine tool 1 by driving the traveling base 12, moves in the machine body front-back direction by driving the front-back slide base, and furthermore, the elevating arm 13 moves. By moving up and down, the chuck devices 21 and 22 or the gripped workpiece W are transported to a predetermined position.

Both of the chuck devices 21 and 22 are three-jaw chucks, and the workpiece W can be gripped and released by synchronously opening and closing the three chuck claws 51 arranged at equal radial intervals. The robot hand 15 has a support portion 24 fixed to the lower end of the lifting arm 13 , and a turning portion 23 is assembled to the support portion 24 via a bearing portion 25 . A servomotor 26 is built in the support portion 24 as a turning motor, and its rotation is transmitted from the bearing portion 25 to the turning portion 23 .

In the machine tool 1 that is automatically controlled, it is necessary to confirm the state in which the robot hand 15 is gripping the work W. Therefore, the automatic work transfer machine 7 also operates the chuck claws 51 in the same manner as in the conventional example. A chuck detector is provided to detect. FIG. 3 is an image diagram showing a part of the chuck detection device in the automatic work transfer machine 7. As shown in FIG. The chuck detection device of this embodiment uses the proximity sensor 31 as in the conventional example. The proximity sensor 31 is provided in each of the chuck devices 21 and 22 and incorporated in the revolving portion 23 so as to detect the gripping operation of the workpiece W by the chuck claws 51 .

The chuck devices 21 and 22 have a hydraulic mechanism for opening and closing the chuck claws 51 by hydraulic pressure. Therefore, a hydraulic hose 27 (see FIG. 2) is attached to the rotating robot hand 15 along the lifting arm 13, and hydraulic oil is supplied to the robot hand 15 via a rotary joint provided in the bearing portion 25. It's like Therefore, in this embodiment, a wireless transmission system is used for the chuck detection device so as not to interfere with the rotatable function of the robot hand 15, and the detection signal of the proximity switch 31 is transmitted to the control device. It is

In the chuck detection device, a movable-side transmission coil 33 connected to a proximity switch 31 is incorporated on the rotating portion 23 side of the bearing portion 25 , and a fixed-side transmission coil 35 is mounted on the supporting portion 24 side that supports the rotating portion 23 . It has been incorporated. The movable-side transmission coil 33 and the fixed-side transmission coil 35 are installed close to each other with their rotation centers aligned with the rotation axis O. As shown in FIG. This wireless transmission system is a wireless system in which electric power is transmitted by the magnetic induction action of the movable-side transmission coil 33 and the fixed-side transmission coil 35 so that electric power and detection signals can be wirelessly transmitted to the rotating revolving part 23 side. A contact power transfer system is adopted. The fixed-side transmission coil 35 is connected to a power supply and to a control device (not shown) through an amplifier.

By the way, in the conventional turning control for rotating the robot hand forward and backward, the output of the turning motor is switched. A control program was required to confirm the positions of 21 and 22 . The automatic workpiece transfer machine of the present embodiment focuses on such conventional problems, and employs a wireless transmission system so as not to hinder the rotatable function of the robot hand 15 as described above. That is, the wireless transmission system can eliminate the restriction on the rotation angle, and the robot hand 15 is configured to be controlled to turn by only rotating in one direction without reversely controlling the servomotor 26, which is a turning motor. .

FIG. 4 is a diagram showing the positional relationship between the chuck devices 21 and 22 from the right side of FIG. The chuck device 21 is arranged downward, and the chuck device 22 faces sideways. In the automatic work transfer machine 7, the work W is transferred between the machine tool 1, the work stocker 3, and the inspection device 5, and the work W is delivered at each location. will be replaced. At this time, according to the automatic work transfer machine 7 of the present embodiment, the robot hand 15 is controlled to rotate only clockwise as indicated by the solid line arrow in FIG.

Therefore, according to the automatic work transfer machine 7 of the present embodiment, by controlling and managing the correspondence between the positions of the chuck devices 21 and 22 and the rotation angles of the servo motors, the robot hand 15 can be rotated only by rotating in one direction. can be made That is, conventionally, the turning section 23 had to perform control including a determination of switching between turning clockwise and counterclockwise indicated by the dashed line in FIG. A simple control that has been lost is possible. In addition, since the rotation can be repeated in the same direction, even if the robot hand has many rotation stop positions of the chuck device different from the present embodiment, it can be moved to the next rotation position at a small rotation angle. A so-called short cut becomes possible.

Although one embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made without departing from the scope of the invention.
For example, in the above-described embodiment, the robot hand 15 having a structure in which the chuck devices 21 and 22 are exchanged at two positions was shown as an example. There is no particular limitation as long as it is a hand.
Further, in the above-described embodiment, the gantry type is described as an example of the automatic work transfer machine, but an automatic work transfer machine using a different type of multi-joint robot may be used.
Further, in the above-described embodiment, the effect of rotating the rotating portion 23 only in one direction is shown, but the function of rotating in the opposite direction is not excluded.

DESCRIPTION OF SYMBOLS 1... Machine tool 3... Work stocker 5... Inspection apparatus 7... Automatic work transfer machine 13... Lifting arm 15... Robot hand 21, 22... Chuck device 23... Turning part 24... Support part 25... Bearing part 26... Servo motor 31 … Proximity sensor … 51 … Chuck claw W … Work

Claims (2)

A rotatable device comprising a revolving part equipped with a chuck device that grips and releases a workpiece by the action of gripping claws, a support part that supports the revolving part, and a revolving motor built in the support part that revolves the revolving part. with a robot hand,
a control device that controls turning of the robot hand;
A fixed-side transmission coil incorporated in the support portion and a movable-side transmission coil incorporated in the revolving portion that transmits a detection signal of a detection switch that is non-contact with the fixed-side transmission coil and detects the operation of the gripping claws. and a chuck detection device that transmits the detection signal to the control device;
Work automatic transfer machine with 2. The automatic workpiece transfer machine according to claim 1, wherein said turning motor is a servomotor, and said control device controls the turning position of said chuck device only by rotating in one direction.

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