CNC machining center is a CNC machining equipment with tool magazine and automatic tool changer. It has many types of tool magazines, so the method of tool change and the writing and execution of tool change commands are also different. We will summarize the tool change methods and their instructions for several common tool magazines.
Most of the umbrella type of tool magazine is changed by a fixed address. And there is a one-to-one correspondence between the tool number and the tool holder number. The tool change action is realized by the lateral movement of the tool magazine and the up and down movement of the spindle. Since there is no tool changer, the tool selection action cannot be preselected before the tool change action. Instead, the tool change command and the tool selection command are written in the same block. And the instruction format is M06 TXX.
When executing this command, the tool magazine first finds the tool holder corresponding to the tool number that needs to be replaced on the spindle in the command, and turns it to the tool change position, so that the tool on the spindle can be changed back into the tool holder. Then the tool magazine finds the tool that needs to be replaced in the command, turns it to the tool change position, and replaces it with the spindle. Because the tool cannot be pre-selected, this command is invalid if Tx x is placed before M06. The final tool selection is executed when M06 is executed. If there is no Tx x after M06, the system will report an error.
The disc type tool magazine generally adopts the tool change mode of random address. The number of tool and the tool holder are not a one-to-one correspondence. But the numerical control system can memorize the corresponding relationship. The disc type magazine uses a robot to change the tool, and the newly changed tool can be preselected before the tool change.
The tool command Tx x controls the magazine rotation and moves the selected tool to the tool change position. The tool change command M06 controls the movement of the tool changer, thereby realizing the exchange of the new and old tools at the spindle tool and the tool change position. Moreover, its tool selection command and tool change command can be written in the same block or in different blocks. Therefore, the tool selection and tool change actions can also be performed together or separately. And the command format is TXXM06. When this command is executed, the magazine first transfers the tool to be changed in the command to the tool change position. And then the robot exchanges the tool and the spindle tool.
We know two types of tool change, we can compare which is better. As a result, the processing efficiency of the second tool change method is improved.