Function introduction of vertical band saw

Update:16-03-2023
Summary:

Function introduction of various parts of vertical band […]

Function introduction of various parts of vertical band saw
The structure of the vertical band saw is relatively complex, and each component needs precise cooperation to complete the processing action. So how do the components of the vertical band saw achieve various functions? Today we will give a detailed introduction to the functions of each component.
Compared with the general mechanical system, the electromechanical integration system should not only have higher positioning accuracy, but also have good dynamic response, that is, fast response and good stability. The vertical band saw system is generally composed of transmission parts, guide support parts, rotating support parts, shafting and frame body. In order to ensure the transmission accuracy and working stability of the mechanical system, the design of each component is often required to have no clearance, low friction, low inertia, high stiffness, high resonant frequency, and appropriate damping ratio.
The following is a brief introduction to the functional parts of the vertical band saw equipment:
(1) Cutting parts
The cutting parts are electric reciprocating saws. The saw blade moves back and forth at the frequency of 500-3000 times/min, and the sawing motion is completed through the reciprocating motion of the saw blade. The machining of curve path is completed through longitudinal feed, transverse feed and vertical rotation feed.
(2) Feed system
The feed system of the vertical band saw designed this time includes longitudinal feed, transverse feed and rotary feed. The curve path is processed through the linkage of the three. Its structure is shown in the figure.
The following describes the motion transformation components and guide support components in the feed system.
1. Motion transformation part
Motion conversion is required in longitudinal feed and transverse feed, that is, the rotary motion of stepping motor is converted to linear motion. The rotation feed controls the rotation angle of the saw blade, mainly through the stepper motor through the transmission parts with large transmission ratio to obtain the rotation feed during the sawing process. Common components that can realize motion transformation include rotary drive (screw nut mechanism), gear rack drive, synchronous belt drive, and transmission components with large transmission ratio include worm gear and worm drive and harmonic gear drive. The motion transformation component selected in this design is gear and rack transmission, and the transmission component with large transmission ratio is worm gear and worm transmission. Transmission components transmit torque and speed, which is a torque and speed converter. Its purpose is to make the actuator and load get a corresponding good match in torque and speed. Transmission type, transmission mode, transmission rigidity and transmission reliability have a significant impact on the accuracy, stability and rapid response of electromechanical integration system. Therefore, the transmission components designed and selected should have the advantages of small transmission clearance, high accuracy, small size, light weight, smooth movement, large transmission torque, etc.
2. Guide support parts
The feed motion needs to be realized on the supporting parts, and certain guiding accuracy is required. The function of guide bearing parts is to support and limit the movement of moving parts according to the given movement requirements and the specified movement direction. Such parts are called guide rails. The basic requirements for guide rails are high guidance accuracy, good rigidity, light and stable movement, good wear resistance, small impact of temperature change, and good structural technology. The commonly used vertical band saw guide rail types are divided into sliding guide rail, rolling guide rail, liquid medium friction guide rail, gas, liquid guide rail and elastic friction guide rail. In this design, the longitudinal feed and transverse feed adopt 25mm precision linear guide rail.
3. Bed
The accuracy and durability of the vertical band saw are mainly guaranteed by the main body of the machine tool. The static and dynamic geometry of the main body of the machine tool has a great impact on the accuracy. For example, the rigidity of the main body, the rotation accuracy of the main shaft, the smoothness of the moving parts, the straightness of the motion, and the parallelism of the motion and the center line of the main shaft. The influence of perpendicularity and thermal deformation. The lathe bed is an important part of the main body of the machine tool. It is necessary to fully consider its static and dynamic characteristics, improve its rigidity, increase its natural frequency, and reduce the impact of vibration on the machining accuracy of the machine tool. The vertical band saw machine body in this design is of welded structure, which has the advantages of light weight, few modified blocks, few waste products, short production cycle, and low cost. In the design, it should meet the requirements of high stiffness and natural frequency, and vibration resistance as much as possible.
4. Travel switch
In order to limit the limit position of the transverse and longitudinal feed of the machine tool, a travel switch must be installed at the end of each guide rail. The travel switch can be divided into electromechanical type and photoelectric type. The photoelectric travel switch is selected for this machine tool. Photoelectric switch is composed of transmitter, receiver and detection circuit. The transmitter aims at the target and emits a beam, which generally comes from light emitting diodes and laser diodes. The beam is emitted continuously, or the pulse width is changed. The radiation intensity of the pulse modulated beam is selected several times during the launch, and it moves towards the target without intermission. The receiver consists of a photodiode or a photoelectric triode. In front of the receiver, optical elements, such as lens and aperture, are installed. Behind it is the detection circuit, which can filter out the effective signal and apply it.
The above is a detailed introduction to the functions of each component of the vertical band saw.