The vibration shell machine is a key equipment used in the investment casting (lost wax casting) process to remove ceramic shells from the surface of castings. It uses high-frequency vibration to break and detach the shells. The following introduces its structural composition, working principle, characteristics, and application scenarios:
1、 Structural composition
The core structure of the vibrating shell machine is designed around the "vibration crushing" function, mainly including:
1. Vibration system: The core is the vibration motor (or eccentric block vibration mechanism), which drives the eccentric block to rotate at high speed and generate high-frequency vibration, providing power for the crushing of the shell; Some large equipment will be equipped with shock-absorbing springs to balance the vibration impact force and protect the equipment foundation.
2. Bearing device: A vibration table or hopper usually made of metal material, used to place castings (with molded shells) of the shell to be vibrated. The table should have high strength and impact resistance to avoid long-term vibration deformation.
3. Protection system: including enclosed or semi enclosed protective covers to prevent injury caused by splashing of shell fragments during the vibration process; Some devices are also equipped with dust removal interfaces, which can be connected to dust removal equipment to reduce dust pollution.
4. Electric control system: composed of control panel, frequency converter, overload protection device, etc., used to adjust vibration frequency (usually adjustable within the range of 50-100Hz), control start stop, and have safety protection functions such as overload and leakage.
2、 Working principle
The working logic of the vibrating shell machine is based on "vibration fatigue crushing", and the specific process is as follows:
1. Workpiece placement: Place the castings (usually in a high-temperature state where the shell is still brittle) that have been cast and are to be removed into a vibration table/hopper.
2. Start vibration: Start the vibration motor through the electronic control system, and the motor drives the eccentric block to rotate, generating high-frequency and directional vibration force that is transmitted to the bearing device.
3. Shell fragmentation: The vibration force causes repeated relative displacement and impact between the casting and the shell, and the shell gradually cracks and fractures due to its brittle material and poor fatigue resistance.
4. Shedding separation: The fragmented shell separates from the surface of the casting under continuous vibration, and is ultimately discharged from the gaps or discharge ports of the load-bearing device, leaving the casting with a clean surface.