Do you know what components the disc – type tool magazine of a CNC machining center consists of?

Disc-Type Tool Magazine of CNC Machining Centers: Structure, Applications, and Tool-Changing Methods

I. Introduction
In the field of CNC machining centers, the tool magazine is a crucial component that directly affects the machining efficiency and automation level. Among them, the disc-type tool magazine is widely used due to its unique advantages. Understanding the components, application scenarios, and tool-changing methods of the disc-type tool magazine is of great significance for in-depth comprehension of the working principles of CNC machining centers and the improvement of machining quality.

 

II. Overview of the Types of Tool Magazines in CNC Machining Centers
Tool magazines in CNC machining centers can be classified into various types according to their shapes. The disc-type tool magazine is one of the more common and widely used types. The disc-type tool magazine is also known as the tool-arm type tool magazine or the manipulator tool magazine. Besides the disc-type tool magazine, other types of tool magazines differ in shape and working principles. For example, the umbrella-type tool magazine is also a common type, but there are differences in tool-changing speed and other aspects compared with the disc-type tool magazine.

 

III. Components of the Disc-Type Tool Magazine

 

(A) Tool Disk Components
The tool disk components are one of the core parts of the disc-type tool magazine and are used to store cutting tools. There are specific tool slots on the tool disk. The design of these slots can ensure that the cutting tools are stably placed in the tool disk, and the size and precision of the slots match the specifications of the cutting tools used. In terms of design, the tool disk needs to have sufficient strength and rigidity to withstand the weight of the cutting tools and the centrifugal force generated during high-speed rotation. Meanwhile, the surface treatment of the tool disk is also important. Usually, wear-resistant and anti-rust treatment methods are adopted to extend the service life of the tool disk.

 

(B) Bearings
Bearings play a crucial supporting role in the disc-type tool magazine. They can keep components such as the tool disk and the shaft stable during rotation. High-precision bearings can reduce friction and vibration during rotation, improving the working precision and stability of the tool magazine. According to the load and rotation speed requirements of the tool magazine, different types and specifications of bearings, such as roller bearings and ball bearings, will be selected. These bearings need to have good load-carrying capacity, rotation precision, and durability.

 

(C) Bearing Sleeves
Bearing sleeves are used to install bearings and provide a stable installation environment for them. They can protect the bearings from being eroded by external impurities and ensure the correct position and concentricity of the bearings after installation. The material of the bearing sleeves is usually selected from metal materials with certain strength and wear resistance, and the machining precision of the bearing sleeves has an important impact on the normal operation of the bearings and the performance of the entire tool magazine.

 

(D) Shaft
The shaft is a key component that connects the tool disk and power components such as the motor. It transmits the torque of the motor to enable the tool disk to rotate. The design of the shaft needs to consider its strength and rigidity to ensure that no deformation occurs during the power transmission process. Meanwhile, the connection parts between the shaft and other components need to have good fitting precision, such as the fitting with the bearings, to reduce shaking and energy loss during rotation. In some high-end disc-type tool magazines, the shaft may adopt special materials and machining processes to meet higher performance requirements.

 

(E) Box Cover
The box cover mainly plays a role in protecting the internal components of the tool magazine. It can prevent dust, chips, and other impurities from entering the inside of the tool magazine and affecting its normal operation. The design of the box cover usually needs to consider sealing and ease of disassembly to facilitate the maintenance and inspection of the internal parts of the tool magazine. In addition, the structure of the box cover also needs to consider the coordination with the appearance and installation space of the entire tool magazine.

 

(F) Pull Pins
Pull pins play an important role in the tool-changing process of the tool magazine. They are used to pull out or insert cutting tools from or into the slots of the tool disk at specific moments. The movement of the pull pins needs to be precisely controlled, and the design and manufacturing precision directly affect the accuracy and reliability of tool changing. Pull pins usually work in coordination with other transmission components to realize the insertion and extraction operations of cutting tools through mechanical structures.

 

(G) Locking Disc
The locking disc is used to lock the tool disk when the tool magazine is not working or in a specific state to prevent the tool disk from rotating accidentally. It can ensure the stable position of the cutting tools in the tool magazine and avoid tool position deviation caused by the shaking of the tool disk during the machining process. The working principle of the locking disc is usually realized through the cooperation between the mechanical locking mechanism and the tool disk or the shaft.

 

(H) Motor
The motor is the power source of the disc-type tool magazine. It provides torque for the rotation of the tool disk, enabling the tool magazine to realize tool selection and tool-changing operations. According to the design requirements of the tool magazine, a suitable power and rotation speed motor will be selected. In some high-performance machining centers, the motor may be equipped with advanced speed regulation and control systems to realize more precise rotation speed control of the tool disk and meet the requirements of different machining processes for tool-changing speed.

 

(I) Geneva Wheel
The Geneva wheel mechanism has an important application in the indexing and positioning of the disc-type tool magazine. It can make the tool disk rotate precisely according to the predetermined angle, thereby accurately positioning to the required tool position. The design and manufacturing precision of the Geneva wheel have a crucial impact on the tool positioning precision of the tool magazine. Through cooperation with power components such as the motor, it can realize efficient and accurate tool selection functions.

 

(J) Box Body
The box body is the basic structure that accommodates and supports other components of the tool magazine. It provides installation positions and protection for components such as bearings, shafts, and tool disks. The design of the box body needs to consider the overall strength and rigidity to withstand various forces during the operation of the tool magazine. Meanwhile, the internal space layout of the box body should be reasonable to facilitate the installation and maintenance of each component, and issues such as heat dissipation should be considered to avoid affecting the performance of the tool magazine due to excessive temperature rise during long-term operation.

 

(K) Sensor Switches
Sensor switches are used in the disc-type tool magazine to detect information such as the position of cutting tools and the rotation angle of the tool disk. Through these sensor switches, the control system of the machining center can real-time understand the state of the tool magazine and precisely control the tool-changing process. For example, the tool-in-place sensor can ensure the accurate position of the cutting tool when it is inserted into the slot of the tool disk or the spindle, and the tool disk rotation angle sensor helps to precisely control the indexing and positioning of the tool disk to ensure the smooth progress of the tool-changing operation.

 

IV. Applications of the Disc-Type Tool Magazine in Machining Centers

 

(A) Realizing Automatic Tool-Changing Function
After the disc-type tool magazine is configured in the machining center, it can realize automatic tool changing, which is one of its most important applications. During the machining process, when the cutting tool needs to be changed, the control system drives components such as the motor and the manipulator of the tool magazine according to the program instructions to automatically complete the tool changing without human intervention. This automatic tool-changing function greatly improves the continuity and efficiency of machining and reduces the downtime during the machining process.

 

(B) Improving Machining Efficiency and Precision
Since the disc-type tool magazine can realize automatic tool changing, the workpiece can complete multiple processes such as milling, boring, drilling, reaming, and tapping under the condition of one clamping. One clamping avoids the positioning errors that may occur during multiple clamping processes, thereby greatly improving the machining precision. Meanwhile, the fast tool-changing speed makes the machining process more compact, reducing the auxiliary time and improving the overall machining efficiency. In the machining of complex parts, this advantage is more obvious and can effectively shorten the machining cycle and improve the production efficiency.

 

(C) Meeting the Needs of Multiple Machining Process Requirements
The disc-type tool magazine can accommodate various types of and specifications of cutting tools, which can meet the requirements of different machining processes. Whether it is a large-diameter milling cutter needed for rough machining or a small-diameter drill bit, reamer, etc. needed for finishing machining, they can all be stored in the tool magazine. This makes the machining center not need to frequently change the tool magazine or manually change the cutting tools when facing different machining tasks, further improving the flexibility and adaptability of machining.

 

V. Tool-Changing Method of the Disc-Type Tool Magazine
The tool-changing of the disc-type tool magazine is a complex and precise process completed by the manipulator. When the control system of the machining center issues a tool-changing instruction, the manipulator starts to move. It first simultaneously grasps the cutting tool being used on the spindle and the selected cutting tool in the tool magazine, and then rotates 180°. This rotation movement requires high-precision control to ensure the stability and position accuracy of the cutting tools during rotation.
After the rotation is completed, the manipulator accurately places the cutting tool taken from the spindle into the corresponding position of the tool magazine, and at the same time installs the cutting tool taken from the tool magazine onto the spindle. During this process, components such as pull pins and sensor switches work in coordination to ensure the accurate insertion and extraction of the cutting tools. Finally, the manipulator returns to the origin, and the entire tool-changing process is completed. The advantage of this tool-changing method lies in its fast tool-changing speed and high accuracy, which can meet the requirements of modern machining centers for efficient and precise machining.

 

VI. Development Trends and Technological Innovations of the Disc-Type Tool Magazine

 

(A) Improving Tool-Changing Speed and Precision
With the continuous development of machining technology, higher requirements are put forward for the tool-changing speed and precision of the disc-type tool magazine. Future disc-type tool magazines may adopt more advanced motor driving technologies, high-precision transmission components, and more sensitive sensor switches to further reduce tool-changing time and improve tool positioning precision, thereby improving the overall machining efficiency and quality of the machining center.

 

(B) Increasing Tool Capacity
In some complex machining tasks, more types and quantities of cutting tools are needed. Therefore, the disc-type tool magazine has a trend of developing towards increasing tool capacity. This may involve innovative design of the tool disk structure, more compact component layout, and optimal utilization of the overall space of the tool magazine to accommodate more cutting tools without increasing the volume of the tool magazine too much.

 

(C) Enhancing Intelligence and Automation Degree
Future disc-type tool magazines will be more closely combined with the control system of the machining center to achieve a higher degree of intelligence and automation. For example, the tool magazine can monitor the wear situation of cutting tools in real time through sensors and feed the information back to the control system. The control system will automatically adjust the machining parameters or prompt to change the cutting tools according to the wear degree of the cutting tools. Meanwhile, the fault diagnosis and early warning functions of the tool magazine will be more perfect, which can timely discover potential problems and reduce the downtime caused by tool magazine faults.

 

(D) Deep Integration with Machining Processes
The development of the disc-type tool magazine will pay more attention to the deep integration with machining processes. For example, for different material processing (such as metal, composite materials, etc.) and different machining shapes (such as curved surfaces, holes, etc.), the tool selection and tool-changing strategies of the tool magazine will be more intelligent. Through combination with machining process planning software, the tool magazine can automatically select the most suitable cutting tools and tool-changing order to improve machining quality and efficiency.

 

VII. Conclusion
As an important component of CNC machining centers, the disc-type tool magazine has a complex and precise structure that determines its excellent performance during the machining process. From the tool disk components to various control and transmission components, each component plays an indispensable role. The wide application of the disc-type tool magazine not only improves the automation level and machining efficiency of the machining center, but also ensures the machining precision through the precise tool-changing method. With the continuous development of the manufacturing industry, the disc-type tool magazine still has great potential in technological innovation and performance improvement and will continue to develop towards being faster, more accurate, and more intelligent, bringing more convenience and value to the CNC machining industry.