JP3925570B2 - Loader control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a loader control device that controls a loader installed in a machine tool such as a lathe.
[0002]
[Prior art]
A loader such as a gantry loader is used to supply a work to a machine tool such as a lathe and carry out the work from the machine tool. In general, such movement of the loader is performed by setting the acceleration / deceleration time constant and the maximum speed to a constant value regardless of the type of workpiece to be machined. Therefore, depending on the type of workpiece, the loader cycle time may be shorter than the time required for the machine tool to finish machining one workpiece. In such a case, conventionally, the loader is stopped and waited until the machining of the workpiece is completed.
[0003]
[Problems to be solved by the invention]
However, in the conventional case, since the loader remains in the standby position without doing anything, there is a problem in terms of loader operation efficiency. Further, when the loader is run at a high speed or suddenly accelerates or decelerates, the vibration may affect the machining. In particular, in finishing, there is a case where the influence of vibration caused by the travel of the loader on machining accuracy cannot be ignored.
In order to increase the workpiece machining cycle time, it may be necessary to run the loader at a high speed. However, in the above-described conventional example, even if a waiting time occurs in the loader, a predetermined constant acceleration / deceleration time constant is set. Since the loader is moved at the maximum speed, the loader is unnecessarily moved at high speed, resulting in a decrease in machining accuracy and a decrease in the loader life due to the use of the loader near the maximum specification.
[0004]
The present invention solves such a problem, and provides a loader control device capable of suppressing a decrease in loader operating efficiency and preventing a decrease in workpiece machining accuracy due to vibration caused by the movement of the loader. For the purpose.
[0005]
[Means for Solving the Problems]
The configuration of the present invention will be described with reference to FIG. 1 corresponding to the embodiment. The loader controller, the loader (6), during machining of the machine tool (2), a loader control device to operate for the supply and discharge of the workpiece (W) relative to the machine tool (2), b over A time measuring means (21) for measuring the waiting time of the loader (6) relative to the processing time of the workpiece (W) from the cycle time of the workpiece conveyance by the da (6) and the time required for workpiece processing, and the time measuring means (21) depending on the timed wait, that much to reduce the moving speed or acceleration and deceleration of the loader (6) low latency, and a cycle time control means (23) for controlling the cycle time of b over da It is a thing.
According to this configuration, the loader (6) does not stop in a state of doing nothing until the machining of the workpiece (W) is completed, and a reduction in the operating rate of the loader (6) is suppressed.
In the above configuration, the time measuring means (21) measures the time to wait for the completion of machining of the workpiece (W) at the machining position after the loader (6) approaches the machining position to a predetermined position, and the cycle time control means (23 When the waiting time of a predetermined time or more is measured by the time measuring means (21), the acceleration / deceleration time constant of the loader (6) is lowered or the maximum speed of the loader is lowered in the subsequent loader cycle. Also good.
According to this configuration, the movement speed or acceleration / deceleration of the loader (6) can be kept low by the amount of the waiting time instead of waiting for the workpiece (W) to be machined, so that the vibration caused by the loader movement is also reduced. The influence of the vibration on the machining accuracy of the workpiece (W) can be reduced. Accordingly, it is possible to suppress a decrease in the operation rate of the loader and to prevent a decrease in machining accuracy due to vibration accompanying the loader movement.
[0006]
In these configurations, the cycle time control means (23) includes a horizontal movement control means (24), a vertical movement control means (25), and a waiting time corresponding control axis selection means (22). It is good as a thing. Here, the horizontal movement control means (24) reduces the horizontal acceleration / deceleration time constant of the loader (6) or regulates the maximum speed according to the waiting time measured by the time measuring means (21). The vertical movement control means (25) is a means for lowering the acceleration / deceleration time constant of the loader (6) in the vertical direction or regulating the maximum speed. The waiting time corresponding control axis selection means (22) is a means for causing at least one of the horizontal movement control means (24) and the vertical movement control means (25) to function according to the waiting time.
In the case of this configuration, not only the moving speed or acceleration / deceleration of the loader (6) can be kept low depending on the waiting time of the loader (6), but the speed limit or the like is applied during horizontal movement or vertical movement. Can also be selected, so that the waiting time can be more finely converted into restrictions such as the loader moving speed.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a relationship between a loader control device of this embodiment, a gantry type loader controlled by the loader control device, and a turret type lathe that is a machine tool that supplies and unloads workpieces with the gantry loader. Indicates. The lathe 1 is a parallel twin-axis lathe having a pair of main shafts 3 and 3 and a pair of turrets 4 and 4 corresponding thereto, and is entirely surrounded by a common machine body cover 2 that can be opened and closed. The turret 4 is a frontal polygonal drum shaped with each peripheral surface portion serving as a tool mounting station. The turret 4 can be moved back and forth (in the Z-axis direction) and indexed and rotated. (Not shown) is attached.
[0008]
Above the lathe 1, a gantry loader 6 that runs along the installation rail 5 is installed. The gantry loader 6 is provided with a front / rear moving base 8 on a traveling body 7 that runs on the installation rail 5, a lifting rod 9 is provided on the front / rear moving base 8 so as to be movable up and down, and a loader that holds a workpiece W at the lower end of the lifting rod 9. A header 10 is provided. That is, the traveling body 7 travels horizontally along the installation rail 5 in the left-right direction (X-axis direction), the front-rear moving table 8 moves back and forth (Z-axis direction), and the lifting rod 9 moves vertically (Y-axis direction). By moving up and down, the loader head 10 can move in a three-dimensional direction. In this loader head 10, two loader chucks 11A and 11B are provided on the surface and the lower surface facing the main shaft 3, and the positions of both loader chucks 11A and 11B can be interchanged.
[0009]
On the side of the lathe 1, a rotary work feeder 14 is installed for rotating the pallet 12 on which the workpiece W is placed on a rotary circuit 13 in a predetermined circulation path. The gantry loader 6 supplies the workpiece W from the pallet 12 of the workpiece feeder 14 to the spindle 3 of the lathe 1 and unloads the workpiece W from the spindle 3 to an unloading position (not shown).
[0010]
In FIG. 1, a lathe control device 15 is a computer-type control device that controls the entire lathe 1, and includes a programmable controller and a numerical control device (NC device), and performs an operation that analyzes and executes a machining program 16. A control unit 17 and a servo driver 18 for driving each axis servo motor of the lathe 1 are provided.
[0011]
The loader control device 19 is a computer-type control device that controls the gantry loader 6. The loader control device 19 stores a loader program 20, and includes a time measuring means 21, a waiting time corresponding control axis selecting means 22, and a cycle time control means 23. I have. Each servo motor is controlled according to the loader program 20. The time measuring means 21 is a means for measuring a time for waiting for completion of machining of the workpiece W on the lathe 1 after the gantry loader 6 approaches the workpiece removal position of the lathe 1 in the repetitive operation of the gantry loader 6.
The cycle time control means 23 lowers (that is, lengthens) the acceleration / deceleration time constant of the gantry loader 6 in the subsequent loader cycle when the time waiting means 21 has measured a waiting time of a predetermined time or longer, and the gantry loader 6 It is a means to reduce the maximum moving speed of the. The cycle time control means 23 includes a horizontal movement control means 24 that lowers the acceleration / deceleration time constant when the gantry loader 6 moves in the horizontal direction (X-axis direction) and regulates the maximum movement speed, and the lifting rod 9 of the gantry loader 6. And a vertical movement control means 25 that lowers the acceleration / deceleration time constant when the loader head 10 is moved up and down in the vertical direction (Y-axis direction), and regulates the maximum movement speed.
The waiting time corresponding control axis selection means 22 is a means for selecting which of the horizontal movement control means 24 and the vertical movement control means 25 is to function according to the waiting time measured by the time measuring means 21.
[0012]
Next, the cycle operation control of the gantry loader 6 by the loader control device 19 will be described with reference to FIGS. FIG. 4 shows an operation explanatory diagram when the gantry loader 6 moves horizontally along the installation rail 5 to the workpiece removal position on the main shaft 3 of the lathe 1. When a plurality of the same workpieces W are continuously processed on the lathe 1, as shown in the flowchart in FIG. 5, it is determined whether or not the gantry loader 6 is a new lot before the movement starts ( In step S1), if it is a new lot, the acceleration / deceleration time constant and the maximum speed set value selected by the horizontal movement control means 24 and the vertical movement control means 25 in the previous lot are initialized (step S2). Next, as shown by a solid line in FIG. 4, the gantry loader 6 is accelerated at a predetermined acceleration time constant τ _U set in the loader program 20 and starts to move horizontally (step S3), and a predetermined maximum speed V _{H is obtained.} The horizontal movement continues at that speed, and when it approaches the spindle 3 up to a predetermined distance, it is decelerated with a predetermined deceleration time constant τ _D set in the loader program 20, and when it reaches a predetermined low speed V _L The horizontal movement further continues at the speed and reaches the workpiece removal position on the spindle 3.
[0013]
At this time, if the shutter of the machine body cover 2 surrounding the lathe 1 is in a closed state and the workpiece W is continuously processed, the measurement of the waiting time by the time measuring means 21 is started (step S4). When the measured waiting time is equal to or longer than the predetermined time T1 (step S5), the cycle time control means 23 sets the acceleration / deceleration time constant and the maximum speed in the horizontal movement in the next and subsequent loader cycles in the loader program 20. Instead of the acceleration / deceleration time constants τ _U and τ _D and the maximum speed V _H , the acceleration / deceleration time constant lowering value and the maximum speed limit value preset in a plurality of levels in the horizontal movement control means 24 are selected. The set values τ _U1 , τ _D1 , and V _H1 corresponding to the waiting time T1 are selected (step S6). When the waiting time is equal to or longer than the predetermined time T2 (T1> T2) (step S7), the set value τ _U2 commensurate with the waiting time T1 is set as the acceleration / deceleration time constant and the maximum speed in the horizontal movement in the next and subsequent loader cycles. , Τ _D2 and V _H2 are selected (step S8). On the other hand, when the waiting time is equal to or shorter than the predetermined time T2, such setting value switching is not performed. Depending on the measured waiting time, the function of the vertical movement control means 25 is selected by the waiting time-corresponding control axis selection means 22, and in steps S5 and S6, the acceleration / deceleration time constant in the vertical movement in the loader cycle after the next time is selected. As the maximum speed, set values τ ′ _U1 , τ ′ _D1 and V ′ _H1 that match the waiting time are selected. The acceleration / deceleration time constant lowering set value and the maximum speed limit value set in the vertical movement control means 25 may be set at a plurality of levels as in the case of the horizontal movement control means 24. Each set value may be set as an acceleration / deceleration time constant or a value of the speed itself, or a coefficient such as “increase the acceleration / deceleration time constant by N%” or “decrease the maximum speed by N%”. You may set it with.
[0014]
Thereafter, when the workpiece W is taken out and the operation of one cycle of the gantry loader 6 is completed (step S9), the processing returns to step S1 and the next cycle of the gantry loader 6 unless all the workpieces are processed (step S10). Is started. When it is determined in step S1 that there is no rod renewal, that is, when the same workpiece W as that in the previous cycle is machined, the horizontal movement control means 24 and the vertical movement control means of the cycle time control means 23 are first processed. The loader movement is started at the acceleration / deceleration time constant selected at 25 or the maximum speed (step S11). When the horizontal movement control means 24 selects τ _U1 , τ _D1 as the acceleration / deceleration time constant lowering set value and V _H1 as the maximum speed limit value, the horizontal movement of the gantry loader 6 shows a broken line in FIG. Acceleration, high-speed movement, and deceleration are performed as indicated by. Further, when τ _U2 , τ _D2 and V _H2 as the maximum speed limit value are selected by the horizontal movement control means 24 as the decrease setting values of the acceleration / deceleration time constant, FIG. Acceleration, high-speed movement, and deceleration are performed as indicated by a chain line. The vertical movement of the gantry loader 6 is performed in the same manner even when the decrease setting value of the acceleration / deceleration time constant and the maximum speed limit value are selected by the vertical movement control means 25.
After the start of the loader movement again (step S11), the waiting time measurement (step S4) is performed, and each processing (steps S5 to S8) corresponding to the waiting time is performed in the same manner as described above. Repeated. By performing the measurement every time as described above, the loader traveling can be performed with the optimum set value in accordance with the change of the driving situation.
After the start of loader movement again (step S11), the value set according to the first wait time measurement (step S4) until the lot is updated without performing the wait time measurement (step S4). It is possible to repeat the loader travel. In addition to the horizontal movement control means 24 and the vertical movement control means 25, there is provided a forward / backward movement control means for lowering the acceleration / deceleration time constant when the front / rear moving table 8 is moved back and forth (in the Z-axis direction) or restricting the maximum movement speed. You may make it provide in the cycle time control means 23. FIG.
[0015]
As described above, according to the loader control device 19 of this embodiment, instead of waiting for the machining of the workpiece W to be completed on the lathe 1, the moving speed or acceleration / deceleration of the gantry loader 6 can be kept low by the waiting time. Therefore, the vibration caused by the movement of the loader is reduced accordingly, and the influence of the vibration on the machining accuracy of the workpiece W can be reduced. Moreover, since the load (duty ratio) of the loader 6 decreases due to such a decrease in loader speed, a failure rate can be reduced.
[0016]
Moreover, not only can the movement speed or acceleration / deceleration of the gantry loader 6 be kept low, but also whether the speed limit or suppression of acceleration / deceleration can be applied during horizontal movement or vertical movement can be selected, so the loader movement can be made more finely. You can switch to speed restrictions.
Further, since the horizontal movement control means 24 and the vertical movement control means 25 are set with a decrease setting value of the acceleration / deceleration time constant and a limit value of the maximum speed at a plurality of levels, the loader movement speed and acceleration / deceleration can be more finely limited. .
[0017]
【The invention's effect】
A loader control device according to the present invention is a loader control device that operates a loader for supplying and unloading a work to and from a machine tool during machining of the machine tool. The loader wait time relative to the workpiece machining time is measured from the workpiece machining time, and the loader moving speed or acceleration / deceleration is kept low by the waiting time measured by the timing means. , since cycle time control means controls the loader cycle time, it is not possible to stop in a state loader do nothing until the machining of the workpiece is completed, lowering the loader operation rate is suppressed.
The time measuring means measures time for waiting for the completion of machining of the workpiece at the machining position after the loader approaches the machining position to a predetermined position, and a waiting time longer than the predetermined time is measured by the time measuring means. Then, in the next and subsequent loader cycles, the loader acceleration / deceleration time constant is lowered or the cycle time control means to lower the loader maximum speed is provided. The moving speed or acceleration / deceleration of the loader can be kept low, and the vibration caused by the loader movement can be reduced accordingly, and the influence of the vibration on the machining accuracy of the workpiece can be reduced. In addition, the vibration can be reduced without increasing the cycle time.
For the cycle time control means, a horizontal movement control means for lowering the load acceleration / deceleration time constant or restricting the maximum speed according to the waiting time measured by the time measuring means, and a loader vertical acceleration A vertical movement control means for lowering the deceleration time constant or restricting the maximum speed, and a waiting time corresponding control axis selection means for selecting which of the horizontal movement control means and the vertical movement control means to function according to the waiting time Depending on the loader's waiting time, not only can the loader's moving speed or acceleration / deceleration be kept low, but the speed limit may be applied when moving horizontally or vertically. Since it can be selected, the waiting time can be more finely converted into a limit such as a loader moving speed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a conceptual configuration of an embodiment of the present invention.
FIG. 2 is a plan view showing the configuration of the same embodiment;
FIG. 3 is a perspective view of the same embodiment.
FIG. 4 is an explanatory diagram showing a loader moving operation in the embodiment.
FIG. 5 is a flowchart of the loader moving operation.
[Explanation of symbols]
6 ... Gantry loader 21 ... Time measuring means 22 ... Waiting time corresponding control axis selection means 23 ... Cycle time control means 24 ... Horizontal movement control means 25 ... Vertical movement control means W ... Workpiece

Claims (3)

The loader, during machining of the machine tool, a loader control device to operate for the supply and discharge of the workpiece relative to the machine tool, machining of the workpiece from the time the cycle time and the work machining of the workpiece transport by Russia over da timing means for measuring the loader latency versus time, in accordance with the timed wait by the regimen time unit, so as to suppress low moving speed or acceleration and deceleration of the amount corresponding loader of the waiting time, b over da cycle A loader control device comprising cycle time control means for controlling time.   The time measuring means measures the time to wait for the completion of machining of the workpiece at the machining position after the loader approaches the machining position to the predetermined position, and the cycle time control means measures the waiting time longer than the predetermined time by the time measuring means. The loader control device according to claim 1, wherein the loader acceleration / deceleration time constant is lowered or the maximum loader speed is lowered in a loader cycle after the next time.   The silly time control means includes a horizontal movement control means for lowering the load acceleration / deceleration time constant in the horizontal direction or restricting the maximum speed according to the waiting time measured by the time measuring means, and a loader vertical direction acceleration. Vertical movement control means for lowering the deceleration time constant or regulating the maximum speed, and waiting time corresponding control axis selection means for causing at least one of the horizontal movement control means and the vertical movement control means to function according to the waiting time The loader control device according to claim 1 or 2.

Images