JP3060420B2 - ATC speed control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed control method for automatically changing the turning and pulling-in / out operation speed of a tool changing arm of an automatic tool changing device (hereinafter referred to as ATC) according to the presence or absence of a current tool or a next tool. is there. However, the current tool is a tool mounted on the spindle and includes a tool that is being returned from the spindle to the magazine, and the next tool is a tool to be used next and is a tool that is being transported until the magazine is mounted on the spindle.

[0002]

2. Description of the Related Art Conventionally, the turning and pulling-out operations of a tool change arm of an ATC of an NC machine tool such as a machining center are performed by:
When viewed from the drive system, there are a type using hydraulic pressure as a drive source and a cam type using an AC motor as a drive source. In the hydraulic type, the tool change arm 102 is driven by a hydraulic motor 101 as shown in FIG.
Of the tool change arm 102 by the hydraulic cylinder 103. A cam type using an AC motor as a drive source is a single AC motor as shown in FIG.
The turning cam 105 and the inserting / removing cam 10 are driven by the motor 104.
The turret cam follower 107 that engages with the cam 105 causes the turret cam follower 107 to rotate the tool change arm 111 via the intermediate shaft 108 and the gears 109 and 110, thereby turning the cam 10.
Lever 113 having a cam follower 112 engaging the 6
The insertion / removal operation of the tool change arm 111 is performed by the above operation.

[0003]

The hydraulic and cam type ATCs described in the prior art both have a constant operating speed, and the operating speed is such that a heavy tool is gripped by both gripping claws of the tool changing arm. In this case, the speed is set to a relatively low speed. Therefore, when the transport load is light, ATC
There is a problem that the speed is inefficient and the speed can be increased. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and an object of the present invention is to increase the ATC speed when transferring one tool without the next tool or the current tool. The purpose of the present invention is to provide a speed control method capable of reducing the ATC time.

[0004]

In order to achieve the above object, an ATC speed control method according to the present invention provides an operation of an automatic tool changer for performing a tool change between a tool magazine of an NC machine tool and a spindle. In the speed control method, the presence or absence of the current tool and the next tool is confirmed by a machining program or a tool exchange command from the operation panel, and the speed of the tool exchange arm that is faster than usual in response to the signal of the current tool or the next tool is eliminated. This is to change the operation speed by outputting speed commands for the turning and insertion / removal operations.

[0005]

[Function] When a tool change command is output from the machining program or the operation panel, information on the presence or absence of the current tool and the next tool is read from the tool information memory, and if there is no tool, a high-speed change command is output from the servo motor control unit. To exchange at high speed. If both the current tool and the next tool are present, a normal speed exchange command is output to perform the exchange at the normal speed. Then, when the tool change arm turns 90 ° and separates from the tool, the tool information memory is updated to prepare for the next tool change.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described with reference to FIGS. In the machining center shown in FIG. 2, a column 2 having a sliding surface 2a in the Z-axis direction is provided upright on the rear side of the bed 1, and the spindle head 3 can be moved and positioned on the Z-axis sliding surface 2a. It is mounted. A spindle 4 is rotatably mounted on the spindle head 3, and an automatic tool pulling device (not shown) is incorporated in the spindle 4. A tool magazine device 5 is attached to the left side surface of the column 3, and the tool magazine device 5 has a magazine pot that stores a plurality of tools with the X-axis direction leftward and stores the tools at a lower tool change position. It has a 90 ° turning mechanism for turning the magazine pot indexed by the tool changing device 90 ° and turning it downward.

Magazine frame 6 of tool magazine device 5
The ATC 7 for exchanging tools between the main shaft 4 and the magazine pot is attached to the left side surface 6a. An arm shaft 9 is supported on a cylindrical frame 8B fixed to the frame 8A of the ATC 7 so as to be pivotable and axially movable, and a twin tool exchange arm 10 is fixed to the tip of the arm shaft 9 at a right angle. Have been. A female spline 11 and a ball nut 12 are supported on the frame 8A concentrically with the arm shaft 9 so as to be rotatable only. The ball screw spline 13 is engaged with the ball nut 12 and the female spline 11 so as to be movable in the axial direction and rotatable. The spline 13 is connected to the arm shaft 9 via a joint 20. A turning servomotor 14 is fixed to the frame 8A via a speed reducer 15, and a gear 16 fitted to an output shaft of the speed reducer 15 is fitted to the female spline 11 via an intermediate gear 17. The gear 18 is engaged with the gear 18. Further, a servomotor 19 for insertion and removal is fixed to the frame 8A, and a gear 21 fitted on the output shaft of the servomotor 19 is meshed with a gear 22 fitted on the ball nut 12.

A control system for switching the ATC speed between a normal speed and a high speed includes a tool change command input means for inputting a tool change command from a machining program or an operation panel as shown in a block diagram of FIG. 23, a tool presence / absence determining means 24 for confirming the presence / absence of the current tool and the next tool when a tool change command is input, and providing the tool information to the tool presence / absence determination means 24 by storing the presence / absence information of the current tool and the next tool. A tool information memory 25, a servo motor control unit 26 for outputting a speed command according to the presence or absence of the current tool and the next tool, and a tool change arm 10 which is 90 ° in the opposite direction (in a direction away from the tool).
Tool information updating means 27 for updating the information in the tool information memory 25 upon turning, drive units 28 and 29 for turning and inserting / removing servo motors for the tool change arm, the above-described turning servomotor 14 and the inserting / removing servomotor 19, It consists of. On the other hand, a sliding surface in the Y-axis direction is provided on the front side of the bed 1, and the carriage 31 is mounted on the Y-axis sliding surface so as to be movable and positionable. A table 32 is mounted on the sliding surface in the axial direction so as to be movable and positionable.

Next, as an operation of the present embodiment, a flow chart showing a processing procedure of the processor at the time of tool change of FIG. 4 will be described. In step S1, when a tool change command is input from the tool change command input means 23, the tool presence / absence determination means 24 checks the presence / absence of the current tool from the tool information in the tool information memory 25 in step S2. If there is no current tool in step S3, the tool presence / absence determining means 24 does not confirm the presence / absence of the next tool, and in step S6, sends a high-speed command for tool change from the servo motor control unit 26 to the servo motor drive units 28 and 29. Output.

If there is a current tool in step S3, the tool presence / absence determining means 24 confirms in step S4 whether there is a next tool. If the current tool is present and the next tool is not present in step S5, a high-speed command for tool exchange is output from the servo motor control unit 26 to the servo motor drive units 28 and 29 in step S6. If both the current tool and the next tool are present in step S5, a normal speed command for tool exchange is sent from the servo motor control unit 26 in step S7.
8 and 29 are output. Then, in step S8, after the tool change arm 10 has turned by 180 °, 90
After turning, in step S9, the tool information updating means 27 updates the tool information in the tool information memory.

[0011]

Since the present invention is configured as described above, the following effects can be obtained. The ATC is set to the NC drive, the presence or absence of the current tool and the next tool is determined, and only when one of the tools is gripped to perform the ATC operation, a high-speed exchange command is output to the servo motor control unit to rotate the servo motor at a high speed. Therefore, the ATC time can be reduced without increasing the cost using only the NC software, and once the optimum speed is set, a stable ATC operation with no trouble can be obtained thereafter.

[Brief description of the drawings]

FIG. 1 is a side view of a servo motor drive ATC.

FIG. 2 is a front view of a vertical machining center.

FIG. 3 is a schematic diagram of an ATC of the present embodiment and a block diagram of a control system.

FIG. 4 is a flowchart illustrating a processing procedure of a processor at the time of tool replacement according to the present embodiment.

FIG. 5 is a structural view of a conventional hydraulic ATC.

FIG. 6 is a structural diagram of a conventional cam type ATC driven by an AC motor.

[Explanation of symbols]

Reference Signs List 4 spindle 5 tool magazine 7 ATC 10 tool change arm 11 female spline 12 ball nut 13 ball screw spline 14 turning servomotor 19 insertion / removal servomotor 23 tool exchange command input signal 24 tool presence / absence judgment means 25 tool information memory 26 servomotor control Part 27 Tool information updating means

Claims (1)

(57) [Claims] 1. A method for controlling an operation speed of an automatic tool changer for performing tool change between a tool magazine device of an NC machine tool and a spindle, wherein a current tool is changed by a tool change command from a machining program or an operation panel. And checking the presence or absence of the next tool, and changing the operation speed by outputting a speed command for turning and inserting / removing operation of the tool change arm faster than usual in response to the signal of the current tool or the next tool. ATC
Speed control method.