Application of RFID technology in tool storage cabinet of Intelligent Manufacturing Factory

1. Operation scenery of tool storage cabinet
Intelligent manufacturing CNC machine has become the main flow equipment of machining shop machinery and other operations. Generally, a small CNC machining shop has as many as thousands of tool equipment, plus its supporting parts, a total of more than ten thousand, and as many as hundreds of varieties. With the sharp increase in the number and variety of tools, the production workshop of various types and specifications of the specification and non-standard tools exist together, many tools frequently in the tool warehouse and machine, machine equipment activities and exchanges. At that time, domestic processing workshops rely on craft methods and paper bar code processing tools. Paper bar code in the oil pollution environment, the tool life can only rely on experience. Because of the lack of cutting tools, the formation of many processing processes to stop, machine operators need to spend a lot of time in the search of cutting tools. With the increase of CNC machine varieties and new product varieties of intelligent manufacturing, the existing tool processing plan can no longer meet the needs, so the introduction of radio frequency skills (RFID). RFID is a non-contact automatic identification skills gathered in the 1990s, with fast scanning, small size, anti-pollution ability and strong durability, reusable, penetrating and non-barrier reading, data recall capacity, large security and other characteristics, so in the production of data collection, monitoring, data transmission has a huge potential. In this paper, based on radio frequency skills, the RFID chip is installed on the tool handle, ending the tool information collection and processing, reducing the comprehensive production cost. 　

2. Current situation and demand of tool handling
At home and abroad engaged in tool processing research experts open announced that many tool processing software, but can not meet all the requirements of tool processing, the existing tool processing has the following problems: ① can not analyze the whole life cycle of the tool record and data, just at the moment point to end the tool information collection and monitoring, can not obtain the data of the processing; (2) Traditional tool processing is lack of M2M information interaction, unable to end the integrated processing; ③ The existing tool treatment plan is intended to meet the production demand, without considering the cost problem in the whole life cycle of the tool. In order to solve the above problems and end the policy of more intelligent automation in the manufacturing industry, it is urgent to introduce new RFID identification skills to process tool information. In the process of processing, intelligent processing is carried out for the application of the tool in the machine, the tool parameters are passed to the machine, so that the tool can participate in the machine tool library for the processing program to call. At the end of tool processing, the production time of the tool is written into the RFID of the tool, the end of the tool real-time information collection, tool status tracking and other functions.
3. Operation flow of tool information processing system
Tool information processing system refers to the machine equipment in the manufacturing unit (such as intelligent manufacturing CNC machine, tool instrument, etc.) and RFID reader communication based on the use of radio frequency skills, CNC and RFID electronic label reader to take serial communication skills, the end of the tool in its life cycle of information monitoring and storage processing. The whole life cycle of cutting tools generally includes planning, acquisition, marking, warehousing, lending, installation, application, repayment, regrinding, obsolescence and so on. In this paper, RFID electronic tags specially planned for the tool by Shanghai Yingxin are selected. The handle of the tool is shown in Figure 1. The time of RFID reading and writing labels is 500ms.
The prerequisite for tool processing is that the tool has been set and set by the tool setting instrument. In order to end the corresponding function of the tool, the machine needs to initialize the tool library and write the tool processing time into the RFID of the tool handle. Because the read and write distance of high-frequency RFID is relatively short, the antenna should be close to the RFID electronic tag through the pneumatic device when reading and writing the RFID of the shank.
(1) Initialization of machine tool library
To end the intelligent transmission of NC tool information, firstly rely on intelligent manufacturing NC machine. In order to ensure that the tool is automatically loaded into the tool library and the tool parameters are read into the tool library from the RFID electronic tag, it is necessary to initialize the tool library. The detailed process is described as follows: (1) When the tool changes in the machine, the machine is required to control the cutter head to roll one week (see figure), and all the tools are initialized to the tool library from the beginning; (2) The following operations are required for each knife: CNC drives the cylinder to jack up the RFID electronic label reading head after the instruction, the cylinder is in place, the CNC obtains the induction switch status, and starts the RFID electronic label reader operation; Cylinder condition adhere to 500ms, CNC through serial communication drive RFID reader to read the handle RFID chip operation; Recovery cylinder, CNC test cylinder magnetic induction switch in place, the tool continues to work; (3) The function of demand control: add a button in the CNC operating interface, press the button every time the cutter head automatically rotates one week, to ensure that every time the tool can roll one week, initialize the machine tool library; It is not allowed to install the knife directly into the tool store handle of the machine.
(2) Tool production time record
When unloading the tool, the output value of the tool (processing time) will be written into the tool handling system. The process of writing the machine processing time into the RFID of the tool handle is as follows: (1) Before the machine unloading the tool or after the tool group, the machine records the tool used, the rotary cutter head, one by one write the tool processing time; (2) Cylinder condition adhere to 500ms, CNC through serial communication drive RFID reader and RFID chip on the shank to write operation; ③ Recover the cylinder. After the magnetic induction switch of the cylinder is in place, the cutter head continues to roll.
To ensure the smooth operation of the above plan, we need to add a button in the CNC operating interface, before unloading the knife or after the group of knives, press a button, make the machine rotate a week, and write the tool use time, after all, the end of the tool life control. Pay attention to the operational specifications when performing the planning process. The planning process is shown in Figure 3.
(3) Tool data storage in RFID chip
The tool code is the important information to confess the identity of the tool. It is written into the RFID and processed by the tool code for each tool. In the preparation of the corresponding program, the nominal diameter, nominal length and the corresponding program can be confessed according to the specification type of the tool, and then give the corresponding diameter compensation and length compensation according to the actual situation. Because the same tool can be installed on different machines, the same machine can also process different products, processing products, may also present abnormal situation, so in processing, the need to show the above processing information. Can enter the program control, in the process of processing dynamic display report flash tool code, processing products, product quantity, abnormal information and RFID records in the tool code, tool life, tool has been used time and other information.