JP2000117580A - Transfer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the height of a loader low by providing a holding means for holding a material to be carried to one end of an arm whose other end is rotationally provided about an axis crossing at right angles with the moving direction of a moving body. SOLUTION: A moving body 7 moves on a traveling beam 3 driven by a Z-axis servo motor 8 to a position where the beam is overhung, stores a work 24 completing the machining in a work guide 22 of a work stocker, and receives a blank 23. In this case, a swivel hand 20 is lowered to an appropriate position of the work guide by a composite action in the Z axis direction and Y axis rotation. The swivel hand 20 newly holding the blank 23 is raised by the Y axis rotation and moves to a main machine side by the Z axis after the arm becomes in parallel to the traveling beam 3. The swivel hand 20 holding the new blank 23 is waited on the work stocker or the traveling beam till the machining work in the main machine is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-machine transfer device for a machine tool.

[0002]

2. Description of the Related Art A machine tool loading device has been reduced in size with less floor space, and operability has been improved by integration with a machine. Further, in order to ensure the safety of workers, to facilitate the process connection, and to improve the cost performance due to the integrated structure, many on-machine linear motion types have been introduced.

For example, in an NC lathe, a slant type which is advantageous in terms of chip processing and floor space is predominant, but in a direct-acting NC loader, when the loader arm rises, the arm tip position exceeds the moving body. It protrudes and becomes higher. As a countermeasure, a device has been proposed in which the Y-axis is a multi-joint arm having two or more axes so that the Y-axis does not protrude above the moving body. In order to cope with the Y-axis control as one axis, Japanese Patent Publication No. 6-51256 proposes a device in which the Y-axis is a telescopic arm to suppress the arm rising end.

[0004] Fig. 4 shows an example in which the height of the loader is reduced by using a telescopic type of two stages of a first arm and a second arm. Multi-stage pantograph (Rage tong) on Y axis
FIG. 5 shows a device which is designed so that the arm does not come out of the moving body.

[0005]

When the vertical movement of the loader arm is controlled by the one-axis NC as described in the prior art, there are cases where the rising end position is high and cannot be installed in a factory with a low ceiling. There is also a method of suppressing the rising end by using the Y-axis as a telescopic arm, but there are cases where two stages are inconvenient because a part of the arm is still above the moving body. If the Y-axis is a pantograph, it does not come out above the moving body, but there is a problem in the rigidity of the link structure.

According to the present invention, one axis N of the Y axis described in the prior art is used.
In view of the problem that the rising end of the arm by C protrudes above the moving body and is inconvenient in setting up a factory, the purpose is to set the Y axis (vertical direction) parallel to the Z axis (horizontal direction). The purpose of the present invention is to reduce the height of the loader by using a rotary arm type that operates with a single-axis NC with a single Y-axis NC.

[0007]

In order to achieve the above object, the present invention provides a transfer device comprising: a moving body that moves on a guide;
First driving means for driving the movable body so as to be positionable;
An arm provided at the one end of the moving body so as to be rotatable around an axis orthogonal to a moving direction of the moving body, a second driving means for driving the arm so that the arm can be positioned at an angle, and And a gripper for gripping an object.

A plane including the chuck axis of the main shaft is determined by rotating the arm having a rotation axis on the moving body below the moving body to determine a coordinate position on the Y axis and moving the moving body in the Z direction by two axes NC. The work can be positioned in the inside. Therefore, the holding means is positioned on the work stocker outside the machine to receive the blank, and after being carried into the machine, can be positioned at the center height of the spindle chuck and transferred to the chuck. Further, it is possible to receive the processed workpiece and reversely pass through the same transport path to store the workpiece in a stocker for the workpiece.

Further, the first driving means and the second driving means are controlled synchronously. By synchronously operating the moving means of the moving body and the rotating means of the arm on the Z axis and the Y axis, the work can be attached and detached without interfering with the space such as the front safety slide door, the tool post, and the chuck. It is possible to reciprocate the work transfer path with the work stocker without waste.

[0010] Further, the arm has a first link provided so as to be angularly positionable by the second driving means, and a second link having the same length as the first link and one end rotatably supported by a moving body. And a third link connecting the free ends of the first link and the second link and having the gripping means. A four-bar linkage is formed by the moving body and the first to third links. By doing so, the direction of the gripping means on the third link is kept constant.

In order to attach / detach the work to / from the chuck and to store / remove the work into / from the work stocker, it is necessary to set the center of rotation of the work hand at a fixed angle with respect to the center of the spindle. By fixing the hand to a section of the parallel link, the angle of the third link can always maintain the same inclination angle even when the arm turns.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of a state in which an in-machine work is attached and detached on a lathe provided with an on-machine loader according to the present invention, and FIG.
FIG. 4 is an explanatory side view of a movable body, a rotating arm, and a double hand according to the present invention.

A traveling beam 3 is erected on a column 2 erected and fixed to a frame 1 of the lathe body, and a rack 4 is fixed on the upper surface of the traveling beam. A U-shaped moving body 7 is mounted so as to be movable in the axial direction of the traveling beam 3 while being guided by groove-shaped guides 6A and 6B fitted to guide rails 5A and 5B provided on the upper and lower surfaces of the traveling beam 3. As a means for moving the moving body, a speed reducer 9 for increasing the rotational torque of the Z-axis servomotor 8 is provided on the moving body, and a rack 4 fixed by rotation of a pinion 10 of an output shaft of the speed reducer is provided. In contrast, a moving body 7 is provided so as to be free-running in the Z axis direction. It is also possible to use a belt chain or the like for linear feed.

The traveling beam 3 extends in a cantilever manner above the work stocker 11 for loading and unloading the work, and is configured to be able to carry the work between the machine and the work stocker or the conveyor. A reducer 13 for increasing the rotation of a Y-axis servo motor 12 is provided as a means for rotating the arm on the plane of the moving body 7 facing the front of the main body, and the output shaft of the reducer serves as the center of rotation of the arm.

[0015] A gripping means is provided at the tip of the arm that turns. The gripping means has two chucks for gripping the workpiece in two directions at right angles, and is indexed concentrically with the axis of the chuck of the main spindle by a 180 ° rotation with an axis at right angles to the intermediate link as a rotation axis. That includes a rotating member. As a specific example, it is possible to use a swivel type double hand as a gripping means, and take out the work from the chuck of the spindle and supply a new blank by turning the hand with fluid pressure or a solenoid to limit the replacement work inside the machine Performed in a designated space.

When the hand holding the work is directly fixed to the first link 14, the hand cannot be kept in a fixed direction, so that it is necessary to have a function of controlling the direction of the hand. Here, the first link 14 is an input link, and is also a section of a four-section link mechanism in which opposing links are parallel. The other links form a link mechanism including a second link 15, a fixed link 16, and a third link 17. That is, the first link 14 and the second link 15, and the fixed link 16 and the third link 17 are relatively parallel to each other.

The fixed link 16 is a fixed node, and a turning point of the second link 15 and the fixed link 16 is provided in a direction of 45 ° clockwise with respect to the moving direction of the moving body 7 so that the fixed link is provided on the moving body. 16 is fixed. When the fixed link 16 can be reduced in length to provide a turning treatment point of the fixed link 16 on the moving body, the fixed link 16 can be omitted. One end of the third link 17 parallel to the fixed link 16 is extended beyond the fixed link 16 and beyond the even point, and a swivel type double hand 20 having a turning center 19 as a gripping means is provided at the extended link end. Can be.

The double hand 20 can be turned by 180 ° so that the workpiece gripping direction can be directed to the axial direction of the chuck 25 of the main spindle or the direction of the work guide 22 of the work stocker 11. As the hand, besides a swivel type double hand, a hand that slides and a hand that turns over can be used. As the rotating means of the double hand, a piston cylinder member using hydraulic power as a power source or an electromagnetic rotating means can be employed.

Next, the operation of the present transport apparatus will be described with reference to FIG. 3 (FIG. 1).

FIG. 3 shows that the movable body 7 is driven by the Z-axis servomotor 8 on the traveling beam 3 to move to the overhang position of the beam, and the processed workpiece 24 is stored in the workpiece guide 22 of the workpiece stocker 11. And blank 2
3 is received. In this case, the lowering of the work guide of the swivel hand 20 to an appropriate position is performed by a combined operation of the Z-axis direction and the Y-axis rotation.

The swivel hand 20 newly gripping the blank 23 rises by rotation in the Y-axis and moves to the machine side in the Z-axis after the arm becomes parallel to the traveling beam 3. However, as long as the movement trajectory where the new blank 23 and the machine frame 1 do not interfere is taken, it may be more reasonable to pass the trajectory of the curve obtained by adding the Y-axis operation to the Z-axis operation. The swivel 20 holding the new blank 23 waits on the work stocker or the traveling beam until the processing operation in the machine is completed.

After the cutting is completed, the safety cover is opened and the arm is turned to be able to descend. The moving body 7 moves rightward in the direction of the tool post 26 from a position immediately above the position where the work 24 is attached and detached from the chuck 21. When the moving body 7 starts to descend by the left rotation of the Y axis, the moving body 7 is also returned to the left. In other words, the Y-axis rotates downward while the Z-axis moves leftward, and the two axes are simultaneously subjected to linear interpolation control, whereby the Y-axis can descend in a straight line. By this synthesizing operation, the link 17 of the swivel hand 20 descends without interfering with the tool rest 26 and the chuck 25 until the arm becomes vertical and reaches a position concentric with the chuck of the spindle. At this position, the chuck axis of the main spindle and the chuck axis of the swivel hand 20 coincide with each other.
4. Hand over.

Here, the swivel hand 20 turns the 180 ° and conveys the transported blank 23 to the chuck 25 and moves away from the chuck by Z-axis movement. The process of transporting the work 24 to the work stocker 11 and storing it in the work guide 22 may be the reverse of the process of carrying the blank 23 into the machine. The center height of the chuck of the swivel hand 20 for transferring the work or the blank to and from the chuck 25 may be constant, and the descending position of the tip of the arm may be constant. However, when transferring a blank or a work to and from the work stocker 11, the height position of the chuck of the double hand 20 needs to be determined in accordance with the current height already stacked and placed. In the vicinity of the work stocker, there is no equipment that interferes, and it can be set arbitrarily by combining the Z axis and the Y axis.

By using the four-bar parallel link mechanism, it is possible to accurately position the work holding portion of the swivel hand provided at the end of the link. However, since the weight of the swivel hand portion and the work is added to the tip of the link mechanism of the arm, the design is made in consideration of the weight reduction of the link constituent members and the capacity and reduction ratio of the Y-axis servomotor. According to the present invention, even in the on-machine type loader, it is possible to carry the workpiece without extruding the workpiece holding member onto the traveling beam when exchanging the workpiece.

[0025]

Since the loader arm does not protrude upward due to the traveling beam, it is possible to provide an on-board type loader which can be installed in a factory with a low ceiling. Maintenance is easy due to the adoption of a link mechanism with a simple structure, and there is no difference in cost as compared to a linear NC with a 2-axis NC loader for the Z-axis (linear) and Y-axis (rotation). . Since the movement locus of the hand can be programmed by the user, it is easy to deal with different works.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a state in which an in-machine work is attached and detached in a lathe provided with an on-machine type loader of the present invention.

FIG. 2 is an explanatory side view of a moving body, a rotating arm, and a double hand according to the present invention.

FIG. 3 is an explanatory diagram of a loader outside traveling state and a delivery state of a work stocker according to the present invention.

FIG. 4 is a front view of a lathe with an on-board loader in which a lifting rod portion protruding from a traveling beam is improved according to a conventional technique.

FIG. 5 is an explanatory view of a structure in which a hand is suspended by a pantograph below a moving body in a conventional technique.

[Explanation of symbols]

 Reference Signs List 1 frame 2 support 3 traveling beam 4 rack 5A, 5B guide rail 6A, 6B groove guide 7 moving body 8 Z-axis servo motor 9, 13 reducer 10 pinion 11 work stocker 12 Y-axis servo motor 14 first link 15 second Link 16 Fixed link 17 Third link 18 Arm rotation center 19 Hand rotation center 20 Swivel hand 21 Safety cover 22 Work guide 23 Blank 24 Work 25 Chuck 26 Turret

Claims (3)

[Claims] 1. A transfer device for a machine tool, comprising: a moving body that moves on a guide; first driving means that drives the moving body so as to be positioned; and one end of the moving body in a moving direction of the moving body. An arm rotatably provided about an axis perpendicular to the axis, and a second drive for driving the arm to be angularly positionable.
A transfer device comprising: a driving unit; and a holding unit that holds an object to be transferred at the other end of the arm. 2. The transport device according to claim 1, wherein the first driving unit and the second driving unit are controlled in synchronization. 3. The first link, wherein the arm is provided so as to be angularly positionable by the second driving means,
A second link having the same length as the first link and rotatably supported at one end by the moving body; and a third link connecting the free ends of the first link and the second link and having the gripping means. 3. The transport apparatus according to claim 1, wherein a four-node link mechanism is formed by the moving body and the first to third links, so that the direction of the gripping means on the third link is kept constant.