JPH0857738A - Loader device - Google Patents

Abstract

PURPOSE: To deliver workpieces efficiently to a machine tool by controlling the movement of plural loaders, installed in the travelable state on the same rail, without generating the mutual collision of these loaders. CONSTITUTION: Plural loaders 8A, 8B for delivering workpieces to a machine tool 1 are installed in the travelable state on the same rail 7. A loader control device 14 is provided to control the movement of the respective loaders 8A, 8B independently. The loader control device 14 is provided with a proximity time speed control means 30 for changing the speed forcibly when the relative distance between the adjacent loaders is the reference value or less on the basis of this relative distance obtained from the coordinate value of the individual loaders 8A, 8B. The proximity time speed control means 30 applies speed override of a specified rate when the relative distance between the adjacent loaders 8A, 8B is the first reference value or less and stops when the relative distance is not more than the second reference value shorter than the first reference value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gantry type loader device mounted on a lathe and other machine tools.

[0002]

2. Description of the Related Art In an automatic machine tool such as a lathe, a loader device such as a gantry loader is used for supplying a material work and unloading a product work. However, the conventional loader device usually has
Since only one loader is provided for one machine tool, for example, in a two-axis lathe, while the work is being delivered to one spindle, the work can be delivered to the other spindle. In some cases, waiting time was generated and work efficiency was poor. It is also proposed that two loader chucks are provided in parallel on the loader head and the work is simultaneously delivered to the two spindles. However, such a loader can be used for both spindles. Limited to special applications, such as when performing the same processing simultaneously.

Therefore, an attempt was made to transfer the work to such a machine tool by two loaders traveling on one rail. However, if there are two loaders on the same rail, there is always the risk of collision. Even if sufficient attention is paid when creating the loader program, there is a risk that the two loaders will collide with each other due to a program error, a malfunction due to the operating environment, or the like. Therefore, as a collision prevention measure, an attempt was made to provide a stopper at an intermediate position of the rail and divide the traveling areas of the two loaders so as not to overlap each other. In this case, when the loader approaches the stopper, the traveling is stopped. However, therefore, the two loaders are dedicated to each spindle and cannot be said to travel on the same rail, and are the same as those in which two independent loader devices are simply installed side by side. It is difficult to improve the work efficiency. Further, there is a problem that it is necessary to provide a work supply table and a product discharge table for each spindle.

SUMMARY OF THE INVENTION An object of the present invention is to provide a loader device which can efficiently transfer a work to a machine tool by a plurality of loaders and which does not cause collision between loaders.

[0005]

The structure of the present invention will be described with reference to FIG. 1 corresponding to an embodiment. This loader device (6)
Installs a plurality of loaders (8A, 8B) for delivering workpieces to the machine tool (1) so that they can travel on the same rail (7), and the loaders (8A, 8B) are independent of each other. A loader control device (14) for controlling the movement of the load is provided.

According to a second aspect of the present invention, in the loader device (6), the loader control device (14) is provided with individual loaders (8A, 8A).
On the basis of the relative distance between the adjacent loaders obtained from the coordinate values of B), the speed control means (30) for proximity is provided for forcibly changing the speed when the relative distance becomes equal to or less than the reference value.

According to a third aspect of the present invention, there is provided the loader device according to the second aspect, wherein the proximity speed control means sets a predetermined ratio when a relative distance between adjacent loaders becomes equal to or less than a first reference value. When the velocity override is applied and the second reference value, which is shorter than the first reference value, becomes equal to or less than the second reference value, either one of them is stopped or temporarily waits at a predetermined position.

[0008]

According to the loader device (6), a plurality of loaders (8A, 8A) movably installed on the same rail (7).
Since B) is independently moved and controlled by the loader control device (14), there is a high degree of freedom in the usage pattern of these loaders (8A, 8B), and the work can be efficiently delivered to the machine tool (1). You can The mutually overlapping ranges on the same rail (7) can be set as the travelable range of the plurality of loaders (8A, 8B).

In the loader device (6) according to the second aspect, when the relative distance between the adjacent loaders (8A, 8B) becomes equal to or less than the reference value, the speed control at the time of proximity provided in the loader control device (14). The loader is forced to change speed by means (30). Therefore, the collision between the loaders can be avoided in advance, and even if the collision occurs, it becomes a collision at low speed running, and damage to the loader can be prevented. Further, since the relative distance between the adjacent loaders is obtained from the coordinate values of the loaders, it is not necessary to provide a dedicated sensor, and the configuration of the control device is simplified.

In the loader device (6) according to the third aspect, the speed control of the loader when the relative distance between the adjacent loaders (8A, 8B) becomes equal to or less than the reference value is the first reference value and the first reference value. The loader is decelerated by speed overriding when it is divided into two stages of two reference values and becomes equal to or less than the first relative distance. When it becomes less than the second reference value which is shorter than this, either one of the loaders is stopped or once made to stand by at a predetermined position. Therefore, the loader can be smoothly stopped for avoiding a collision, and it is possible to avoid dropping the workpiece being gripped due to a rapid speed change.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view of a machine tool equipped with the loader device of the present invention. The machine tool 1 is composed of parallel two-axis turret lathes, and has a pair of spindles 2 and 2 and a pair of turrets 3 and 3 corresponding thereto. Turret 3
Is provided so that it can be moved left and right (X axis direction) and forward and backward (Z axis direction) and can be indexed and rotated, and various tools (not shown) are attached to each tool station on the outer periphery of the turret 3. . A material work supply table 4 is installed on one side of the machine tool 1 and a product work discharge table 5 is installed on the other side thereof, and a rail 7 of a loader device 6 is installed above the two boards 4, 5. There is.

The loader device 6 is of a gantry type and has two loaders 8A and 8B which run along a rail 7 which is erected. These loaders 8A and 8B are ones in which an elevating rod 11 is installed on a traveling platform 9 traveling along the rail 7 in the X-axis direction via a front-rear traveling platform 10.
A loader head 12 is attached to the lower end of the lifting rod 11. Travel of the traveling platform 9, forward / backward movement of the forward / backward traveling platform 10 (Z-axis direction), and lifting / lowering of the lifting rod 11 (Y-axis direction).
Is performed by driving a servo motor for each axis mounted on each loader 8A, 8B. The loader head 12 is provided with two loader chucks 13 and 13 in a direction facing the spindle 2 and a downward attitude, and the positions of both loader chucks 13 and 13 are determined by a rotary table (not shown) of the loader head 12. ) Are interchanged by rotating around the tilt axis. Each of the loaders 8A and 8B performs the following operation, for example. That is, these loaders 8A and 8B hold the material work on the material work supply table 4 by the downward loader chuck 13, change the material work into a horizontal posture and supply it to the spindle 2, and the horizontal loader chuck 13 causes the spindle to move. The machined work is received from 2, the work is changed to a downward posture, and the work is discharged onto the product work discharge table 5. In the case where the two main spindles 2 and 2 are used to perform the pre-process and the post-process respectively, the operation of receiving the workpiece of the intermediate product from the main process-side spindle 2 and passing it to the post-process side main spindle 2 is performed. And so on.

The loader device 6 is controlled by the loader control device 14 shown in the block diagram of FIG.
The movements of A and 8B are controlled independently of each other by the first and second individual loader control devices 14A and 14B constituting the loader control device 14. FIG. 2 shows a computer type control device for controlling the entire machine tool 1, which is composed of an NC device (numerical control device) 15, a PC device (programmable controller) 16 and the like, a part of which functions as the loader control device 14. Carry. The axis feed control means 17 provided in the NC device 15 uses the loader program 18 to load the loader 8A,
8B is a means for outputting a movement command for each axis (X, Y, Z axes), and the servo controller 19 is operated by the movement command.
The servomotor 20 is controlled via the. The loader program 18 is provided with a first individual loader program 18A that controls the first loader 8A and a second individual loader program 18B that controls the second loader 8B.
These individual loader programs 18A, 18B may be one program in which the commands of both individual loader programs 18A, 18B are mixed. The servo controller 19 and the servo motor 20 are provided for each of the X-axis to the Z-axis, but in FIG. 2, only the X-axis is shown and the others are omitted. The servo motor 20 has a position detector 21 such as a pulse coder, and is feedback-controlled by the servo controller 19.

The axis feed control means 17 has an override processing means 22, and an override dial 24 of the operation panel 23.
Or an override command from the PC device 16, for example, 0 for the speed command of the loader program 18.
~ 200 percent velocity override is possible. Override command means 2 shown in the PC device 16
5, stop command means 26, and relative distance monitoring means 27
Means a predetermined sequence program stored in the PC device 16 and a hardware configuration for executing the command. The relative distance monitoring means 27 is used for the individual loaders 8A and 8A.
It is a means for monitoring the X-axis relative distance between the adjacent loaders obtained from the X-axis coordinate value of B, and the X-axis relative distance is the first.
It has a means 28 for confirming that the reference value X1 or less has been reached, and a means 29 for confirming that the X-axis relative distance has become equal to or less than the second reference value X2 which is shorter than the first reference value X1.
The override command means 25 responds to the confirmation signal output from the first reference value or less confirmation means 28 and is adjacent to the loader 8.
The axis feed control means 17 is provided with a deceleration travel command for applying a speed override of a predetermined ratio to at least one of A and 8B. The stop command means 26 gives a command to the axial feed control means 17 to stop at least one of the adjacent loaders 8A and 8B in response to the confirmation signal output from the second reference value or less confirmation means 29. Thus, the override command means 25, the stop command means 26, and the relative distance monitoring means 27 use the relative distance as a reference based on the relative distance between the loaders obtained from the X-axis coordinate values of the loaders 8A and 8B. The proximity speed control means 30 is configured to forcibly change the speed when the value is less than or equal to the value.

Next, the movement control of the loaders 8A and 8B will be described with reference to FIG.
~ It demonstrates by the operation example of FIG. In FIG. 3A, both loaders 8A and 8B travel on the rail 7 in the same direction (right side in the figure), and the moving speed V _B of the loader 8B behind the running direction is the moving speed V _A of the front loader 8A. Is faster than. In this case, there is a risk that the loader 8B approaches the preceding loader 8A with the passage of time and eventually collides. In order to avoid this collision, the loader control device 14 performs the following speed control.

When the relative distance between the loaders 8A and 8B becomes equal to or less than the first reference value X1 (step S1), the confirmation signal is given from the first reference value or less confirmation means 28 of the PC device 16 to the override command means 25. In response to this, the override command means 25 gives a speed override command for decelerating the X-axis feed speed of the loader 8B to the axis feed control means 17 (step S2).
As a result, the X-axis traveling speed of the loader 8B is reduced from V _B to V _BO as shown in FIG. Speed V after this deceleration
_{The BO} has a speed that allows it to stop immediately when a collision occurs, for example. After that, when the loaders 8A and 8B approach each other and the relative distance becomes equal to or less than the second reference value X2 (step S3), the confirmation signal from the second reference value or less confirmation means 29 of the PC device 16 to the stop command means 26. In response to this, the stop instruction means 26 gives an instruction to the axis feed control means 17 to stop the loader 8B (step S4). In this way, the adjacent loaders 8A, 8B
It is possible to reliably avoid a situation where the two collide. The stop command (S4) is given by an interlock. When the relative distance between the loaders 8A and 8B becomes normal, that is, when the first reference value X1 is exceeded, the stopped loader 8B The vehicle is returned to normal running (S5, S6). Further, even during low speed running due to speed override, the loader 8B is returned to normal running when the relative distance returns to the normal distance (S7, S).
8). Since such collision avoidance control works automatically, 2
The loader program 18 is created so that the work loader can be transferred to any of the spindles 2 2 without providing a limitation that the loaders 8A and 8B are dedicated to the two spindles 2 and 2. Work can be efficiently performed without wasting time.

In the control operation, the two loaders 8
Although the case where A and 8B move in the same direction is shown, the case where the two loaders 8A and 8B move in opposite directions as shown in FIG. 3 (B), or the loader stopped as shown in FIG. 3 (C). 8
Even when the other loader 8B moves toward A, the collision between the loaders 8A and 8B can be avoided by the movement control similar to the above. When moving oppositely as shown in FIG. 3B, both the loaders 8A and 8B may be controlled to be decelerated and stopped as described above, and the movement of the loader, which is responsible for the priority work, may be continued normally and the other Alternatively, only the loader may be decelerated and stopped. In this case, the loader to be decelerated and stopped may be moved in the opposite direction after the stop and separated from the priority loader. Further, the loader for decelerating may be made to temporarily stand by at a predetermined position. The predetermined position may be a position that does not interfere with the loader on the priority side, and may be the right end or the left end on the rail 7.

Further, in the above-mentioned embodiment, the case of the loader device 6 in which the two loaders 8A and 8B are provided for the single two-axis lathe has been described, but the configuration is as shown in FIGS. May be. In FIG. 6, three loaders 8A, 8B, 8C are installed on the same rail 7 for the machine tool 1 composed of two two-axis lathes, and each can be controlled independently. FIG. 7 shows 1
Two loaders 8A and 8B are installed on the machine tool 1B consisting of one single-axis lathe in the same manner as in the embodiment of FIG. 1. FIG. 8 shows a machine tool 1C consisting of one three-axis lathe. On the other hand, two loaders 8A and 8B are installed in the same manner as in the example of FIG. The movement control of those loaders 8A to 8C is the same as in the case of the previous embodiment. In addition, the present invention can be applied to a case where a plurality of loaders are installed in a machine tool including a facing two-axis lathe.

[0019]

According to the loader device of the present invention, a plurality of loaders, each of which delivers a work to a machine tool, are installed so as to be able to travel on the same rail, and the loaders are independently controlled to move. Since the device is provided, the degree of freedom in usage of each loader is high, two loaders can be efficiently used according to the type of processing, and the work can be delivered to and from the machine tool efficiently.

According to another aspect of the present invention, the loader control device is forced to force the loader control device when the relative distance becomes equal to or less than a reference value based on the relative distance between adjacent loaders obtained from the coordinate values of the individual loaders. Since the speed control means at the time of proximity for changing the speed is provided, it is possible to avoid the collision between the loaders and the damage when the collision occurs. Moreover, it is not necessary to provide a sensor for measuring the relative distance between the loader and the loader drive system, and the configuration of the control system can be simplified.

A loader device according to a third aspect of the present invention is the loader device according to the second aspect.
In the loader device described above, when the relative distance between adjacent loaders is equal to or less than a first reference value, a speed override is applied at a predetermined rate and the speed control means is set to be equal to or less than a second reference value that is shorter than the first reference value. In this case, either one of them is stopped or once held at a predetermined position, so that the loader can be stopped smoothly for collision avoidance, and it is possible to avoid dropping the workpiece being gripped due to a rapid speed change.
In addition, between the first reference value and the second reference value where there is a relatively large distance between the loaders, deceleration is performed without stopping, so that efficiency reduction due to frequent stops is avoided and a collision occurs. It is possible to prevent damage to the loader when it occurs.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a front view of a machine tool equipped with a loader device of the present invention and a conceptual configuration of a control system.

FIG. 2 is a block diagram showing a loader control device of the same loader device.

FIG. 3 is an explanatory diagram showing a relative positional relationship between both loaders in the same loader device.

FIG. 4 is an explanatory diagram of a speed curve showing loader movement control of the same loader device.

FIG. 5 is a flow chart of the same loader movement control.

FIG. 6 is an explanatory view showing a front view of a loader device and a machine tool and a block diagram of a control system according to another embodiment of the present invention.

FIG. 7 is an explanatory view showing a front view of a loader device and a machine tool and a block diagram of a control system in still another embodiment of the present invention.

FIG. 8 is an explanatory view showing a front view of a loader device and a machine tool according to still another embodiment of the present invention and a block diagram of a control system.

[Explanation of symbols]

1 ... Machine tool, 7 ... Rail, 8A, 8B ... Loader, 14
... Loader control device, 25 ... Override command means, 26
... stop command means, 28 ... first reference value or less confirmation means, 29
... second reference value or less confirmation means, 30 ... speed control means in proximity

Claims (3)

[Claims] 1. A loader device comprising a plurality of loaders each of which delivers a work to a machine tool so that the loaders can travel on the same rail, and a loader control device for independently controlling the movement of each loader is provided. 2. A proximity speed control for causing the loader control device to forcibly change the speed when the relative distance becomes equal to or less than a reference value based on a relative distance between adjacent loaders obtained from coordinate values of individual loaders. The loader device according to claim 1, further comprising means. 3. The proximity speed control means applies a speed override of a predetermined ratio when the relative distance between adjacent loaders becomes equal to or less than a first reference value, and further comprises a second speed shorter than the first reference value.
3. The loader device according to claim 2, wherein either one of them is stopped or once made to stand by at a predetermined position when it becomes equal to or less than a reference value.