(1) mold clamping device
The clamping device mainly has three functions: one is to realize the reliable opening and closing of the mold; The second is to ensure that there is enough locking force when injection pressure is maintained to prevent plastic parts from overflowing; The third is to realize the demoulding of plastic parts. The mold clamping device is a device to ensure the complete closure of the mold and smoothly open and close the mold according to the technological requirements. In the injection process of the injection molding machine, under the action of the clamping mechanism, when the high-pressure melt enters the cavity, the mold can still be closed reliably.
The mold clamping device is mainly composed of mold clamping mechanism, demoulding mechanism, mold adjusting mechanism, template, pull rod and so on. The front and rear fixed templates are connected by four pull rods to form an integral rigid frame. The movable template slides between the front fixed template and the rear fixed template. Usually, the demoulding mechanism is located at the back side of the movable template. When the movable die is opened, the plastic part can be ejected from the die cavity through the demoulding mechanism in the die. The movable template or the fixed template is also equipped with a mold adjusting mechanism, which can adjust the thickness of the mold to meet the requirements of molds with different thicknesses.
Due to the different structures of injection molding machines, different production control methods and different complexity of plastic parts, there are generally three kinds of clamping devices: mechanical, hydraulic and hydro-mechanical. The mechanical type generally uses a crank arm or a lever to drive the crank arm to open and close the mold. This type does not meet the requirements of molding process and is rarely used now. I won't introduce this book. The action requirements of mold closing are: from fast to slow before mold closing, slowly open the plastic parts after molding, and then quickly reset and protect the mold to shorten the molding cycle.
(2) Injection device
The injection device has three main functions: first, the plastic is evenly heated, melted and plasticized to reach a flowing state; Secondly, a certain amount of molten material is injected into the mold cavity at a certain pressure and speed; Thirdly, after the injection, keep the pressure of the molten material in the mold cavity and replenish the material in the mold cavity. In order to complete the above functions, the injection device is mainly composed of plasticizing mechanism, hopper, nozzle, barrel and so on.
Plasticizing mechanism is an important part of injection molding machine, which plasticizes plastics homogeneously. Commonly used plasticizing mechanisms are mainly divided into plunger type and screw type. When the plastic enters the barrel from the hopper due to its own weight, it is heated by the heating element outside the barrel and the friction heating of the plasticizing mechanism to become a uniform molten material, and then enters the mold cavity through the nozzle.
(3) Driving device
The driving device mainly has two functions: one is to provide the required power when the injection molding machine moves according to the process requirements; The second is to meet the requirements of moving parts for force and speed in the process of movement. Most of the driving devices used now are hydraulic driving devices. Usually, it consists of a main loop for controlling system pressure and flow and a sub-loop for each actuator. The components that make up the loop mainly include: pump, filter, flow valve, pressure valve, reversing valve, speed regulating valve, travel valve, accumulator, indicating instrument, switching element, etc.
The injection molding machine is driven by hydraulic pressure and works stably and reliably. It cooperates with the control system and is easy to realize the automation of injection molding machine. Hydraulic components can be installed in the machine body, with compact structure and beautiful appearance. At present, the mechanical structure of injection molding machine has not been greatly improved, but a lot of research and improvement have been done in hydraulic drive and control, which makes injection molding machine more accurate, more reliable and more energy-saving.
(4) Control system
The control system is the "brain" of the injection molding machine, which controls all kinds of actions of the injection molding machine, so that they can effectively control and adjust the parameters such as time, position, pressure and speed according to the preset program.
At present, many control systems are still relay control systems, and a few have adopted microcomputer control. The control system can be used for action program control, temperature control, hydraulic pump motor control and so on. It is mainly composed of relays, electronic components, detection components and automation instruments. The organic combination of control system and hydraulic system can accurately and stably control the process program of injection molding machine.
Modern and advanced injection molding machines are equipped with computer monitoring devices and various digital display instruments, and some of them are also equipped with electronic function analyzer, central fault diagnosis device, automatic oil temperature preheating and display device, low-pressure mold protection device, plastic demoulding photoelectric monitoring device, automatic feeding device and plastic part taking-out manipulator. Their organic cooperation makes the control system of injection molding machine almost perfect.
What parts make up the screw of injection molding machine? The screw parts of injection molding machine are generally divided into: screw+retaining ring washer+retaining ring+screw head;
Screw is generally divided into three sections: feeding section, compression section and homogenization section (also called metering section).
Generally speaking, the screw of injection molding machine can be divided into three sections:
Punching part: This is the initial part of plastic entering the screw. When the screw rotates, it can be stirred in advance, so that the materials can be evenly mixed with the masterbatch or other additives.
Compression part: This is the middle part where the material enters the screw. At this time, the thread depth of the screw changes gradually, and the plastic is melted and plasticized through rotation and shearing.
Metering section: this is the last section of the material entering the screw, close to the nozzle. At this time, the plastic has been completely plasticized evenly, waiting for the injection machine to carry out injection operation according to the measured amount.
Type of injection molding machine screw:
Screw is an important part of injection molding machine. Its function is to transport, compact, melt, stir and press plastics. All this is done by the rotation of the screw in the barrel. When the screw rotates, the plastic will generate friction and mutual movement among the inner wall of the barrel, the bottom surface of the spiral groove, the advancing surface of the spiral rib and the plastic.
Graduated screw: the compression section is long, accounting for 50% of the total length of the screw, and the energy conversion is moderate during plasticization, which is mostly used for plastics with poor thermal stability such as PVC.
Mutant screw: the compression section is short, accounting for about 5%~ 15% of the total length of the screw. The energy conversion is fierce during plasticization, and it is mostly used in crystalline plastics such as polyolefin and PA.
Universal screw: universal screw with strong adaptability, which can adapt to the processing of various plastics.
Screw is an important part of injection molding machine. Its function is to transport, compact, melt, stir and press plastics. Divided into universal type, mutant type and gradual type; Production screw materials: 38CrMoAla, SACM645, 42CrMo, etc.
All this is done by the rotation of the screw in the barrel. When the screw rotates, the plastic will generate friction and mutual movement among the inner wall of the barrel, the bottom surface of the spiral groove, the forward surface of the spiral rib and the plastic.
Injection molding machine screw is composed of which parts? Generally divided into: screw+retaining ring gasket+retaining ring+screw head;
Screw is generally divided into three sections: feeding section, compression section and homogenization section (also called metering section).
Generally speaking, the screw of injection molding machine can be divided into three sections:
Punching part: This is the initial part of plastic entering the screw. When the screw rotates, it can be stirred in advance, so that the materials can be evenly mixed with the masterbatch or other additives.
Compression part: This is the middle part where the material enters the screw. At this time, the thread depth of the screw changes gradually, and the plastic is melted and plasticized through rotation and shearing.
Metering section: this is the last section of the material entering the screw, close to the nozzle. At this time, the plastic has been completely plasticized evenly, waiting for the injection machine to carry out injection operation according to the measured amount. Hua Hong replied.
Type of injection molding machine screw:
Screw is an important part of injection molding machine. Its function is to transport, compact, melt, stir and press plastics. All this is done by the rotation of the screw in the barrel. When the screw rotates, the plastic will generate friction and mutual movement among the inner wall of the barrel, the bottom surface of the spiral groove, the advancing surface of the spiral rib and the plastic.
Graduated screw: the compression section is long, accounting for 50% of the total length of the screw, and the energy conversion is moderate during plasticization, which is mostly used for plastics with poor thermal stability such as PVC.
Mutant screw: the compression section is short, accounting for about 5%~ 15% of the total length of the screw. The energy conversion is fierce during plasticization, and it is mostly used in crystalline plastics such as polyolefin and PA.
Universal screw: universal screw with strong adaptability, which can adapt to the processing of various plastics.
Screw is an important part of injection molding machine. Its function is to transport, compact, melt, stir and press plastics. Divided into universal type, mutant type and gradual type; Production screw materials: 38CrMoAla, SACM645, 42CrMo, etc.
All this is done by the rotation of the screw in the barrel. When the screw rotates, the plastic will generate friction and mutual movement among the inner wall of the barrel, the bottom surface of the spiral groove, the forward surface of the spiral rib and the plastic. Hope to adopt
How many parts does the injection molding machine consist of? Someone answered your question, and after you read the answer, you dropped the question without giving points. Who will answer your question again?
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Birds are mainly composed of several parts, and bird hair is the main part.
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What is the basic function of injection molding machine? What are the parts of a general press? Ordinary press is mainly composed of clamping system, plasticizing system, hydraulic system and electrical control system.
The main function of injection molding machine is to produce thermoplastic or thermosetting plastic products.
It is a method of injecting heated and melted materials into the mold cavity, cooling and curing to obtain molded products. Action sequence: mold closing, injection, pressure maintaining, cooling, mold opening and product ejection.
What is the main part of computer virus worm? Worm consists of two parts: main program and loader. Once the main program is established in the computer, it can collect the information of other machines networked with the current machine. It can try to establish a loader on a remote machine by reading the public configuration file and detecting the network status information of the current machine. It is this small program, commonly known as loader, that brings worms to other machines.
What are the main components of CNC machine tools? The basic components of CNC machine tools include machining program carrier, CNC device, servo drive device, machine tool main body and other auxiliary devices. The basic working principle of each component is briefly described as follows.
Handler carrier
When CNC machine tools are working, it is not necessary for workers to directly operate the machine tools. To control CNC machine tools, it is necessary
High-speed CNC machine tool
Processing procedures should be prepared. The machining program of parts includes the relative motion trajectory of cutter and workpiece on the machine tool, process parameters (feed speed, spindle speed, etc.). ) and auxiliary exercise. Parts processing program is stored in a program carrier with a certain format and code, such as punched paper tape, cassette tape, floppy disk, etc. And the program information is input to the CNC unit through the input device of the CNC machine tool.
Digital control equipment
Numerical control device is the core of numerical control machine tool. Modern numerical control devices all adopt the form of CNC (computer numerical control), and generally use multiple microprocessors to realize numerical control functions in the form of programming software, so it is also called software numerical control. Numerical control system is a position control system, which interpolates the ideal motion trajectory according to the input data, and then outputs it to the executive parts to process the required parts. Therefore, the numerical control device is mainly composed of three basic parts: input, processing and output. All these tasks are reasonably organized by computer system programs, so that the whole system can work harmoniously.
1) input device: input NC instructions to NC devices, and there are different input devices according to different program carriers. There are mainly keyboard input, disk input, direct communication input of CAD/CAM system and DNC (direct numerical control) input connected to the upper computer. At present, many systems still keep the paper tape input form of photoelectric readers.
(1) paper tape input mode. The paper tape photoelectric reader can be used to read the part program and directly control the movement of the machine tool. It can also read the paper tape content into the memory and control the movement of the machine tool with the part program stored in the memory.
(2)MDI manual data input mode. The operator can use the keyboard on the operation panel to input the instructions of the machining program, which is suitable for shorter programs.
In the editing state of the control device, the machining program is input by software and stored in the memory of the control device. This input method can reuse the program. This method is often used for manual programming.
On the NC device with dialogue programming function, different menus can be selected according to the questions prompted on the display, and the relevant size numbers can be input through man-machine dialogue to automatically generate the machining program.
(3) DNC direct numerical control input mode is adopted. The part program is stored in the upper computer, and the NC system receives the subsequent program segments from the computer while machining. DNC mode is mostly used for complex workpieces designed by CAD/CAM software, and directly generates part programs.
2) Information processing: the input device transmits the machining information to the CNC unit and compiles it into letters that can be recognized by the computer.
Different types of CNC machine tools (13)
The information processing part stores and processes the information step by step according to the provisions of the control program, and then sends position and speed instructions to the servo system and the main motion control part through the output unit. The input data of numerical control system includes: contour information of parts (starting point, ending point, straight line, arc, etc. ), machining speed and other auxiliary machining information (such as tool change, speed change, coolant switch, etc.). ). The purpose of data processing is to complete the preparatory work before interpolation operation. The data processing program also includes tool radius compensation, speed calculation and auxiliary function processing.
3) Output device: the output device is connected with the servo mechanism. The output device receives the output pulse of the arithmetic unit according to the instruction of the controller and sends it to the servo control system of each coordinate. After power amplification, the servo system is driven to control the machine tool to move according to the specified requirements.
Servo and measurement feedback system
Servo system is an important part of CNC machine tools, which is used to realize feed servo control and spindle servo control of CNC machine tools. The function of the servo system is to convert the command information received from the numerical control device into linear displacement or angular displacement of the execution part of the machine tool after power amplification and shaping. Servo system is the last link of CNC machine tools, and its efficiency will directly affect the accuracy and speed of CNC machine tools and other technical indicators. Therefore, the servo drive device of CNC machine tools is required to have good fast response efficiency, accurately and sensitively track the digital instruction signals sent by CNC machine tools, and faithfully execute the instructions from CNC machine tools, so as to improve the dynamic tracking characteristics and static tracking accuracy of the system.
The servo system consists of two parts: the driving device and the executing mechanism. The driving device consists of a spindle driving unit, a feed driving unit, a spindle servo motor and a feed servo motor. Stepper motor, DC servo motor and AC servo motor are commonly used driving devices.
The measuring element detects the actual displacement values of each coordinate axis of the NC machine tool and inputs them into the NC device of the machine tool through the feedback system. The NC device compares the feedback actual displacement value with the command value, and outputs the displacement command required to reach the set value to the servo system.
Machine tool body
Machine tool host is the main body of CNC machine tools. It comprises a lathe bed, a base, an upright post, a cross beam, a sliding seat, a workbench, a spindle box, a feeding mechanism, a tool rest and an automatic tool changing device. It is a mechanical part that automatically completes all kinds of cutting processing on CNC machine tools. Compared with traditional machine tools, the main body of CNC machine tools has the following structural characteristics:
1) adopts a new machine tool structure with high rigidity, high earthquake resistance and small thermal deformation. Usually, methods such as improving the static stiffness of structural system, increasing damping and adjusting the mass and natural frequency of structural parts are used to improve the stiffness and seismic capacity of machine tool body, so that the machine tool body can meet the needs of continuous automatic cutting of CNC machine tools. The influence of thermal deformation on the main engine can be reduced by improving the structural layout of machine tools, reducing heating, controlling temperature rise and adopting thermal displacement compensation.
2) The wide application of high-efficiency spindle servo drive and feed servo drive device shortens the transmission chain of CNC machine tools and simplifies the structure of mechanical transmission system of machine tools.
3) Adopt transmission devices and moving parts with high transmission efficiency, high precision and no clearance, such as ball screw nut pair, plastic sliding guide rail, linear rolling guide rail and hydrostatic guide rail.
Auxiliary device of numerical control machine tool
In order to ensure the full play of the functions of CNC machine tools, auxiliary equipment is essential. Commonly used auxiliary devices include: pneumatic and hydraulic devices, chip removal devices, cooling and lubricating devices, rotary tables and numerical control indexing heads, protection, lighting and other auxiliary devices.
The laser device is mainly composed of several parts. Laser generally includes three parts.
1, laser working medium
The generation of laser must choose a suitable working medium, which can be gas, liquid, solid or semiconductor. In this medium, the number of particles can be reversed, creating the necessary conditions for obtaining laser. Obviously, the existence of metastable energy levels is very beneficial to realize the reverse cycle of particle numbers. At present, there are nearly a thousand kinds of working media, and the laser wavelength that can be generated includes far infrared from vacuum ultraviolet channel, which is very extensive.
2. Incentive source
In order to reverse the number of particles in the working medium, it is necessary to stimulate the atomic system by certain methods and increase the number of particles in the upper energy level. Generally, gas discharge can be used to excite dielectric atoms with electrons with kinetic energy, which is called electrical excitation; The working medium can also be irradiated by pulsed light source, which is called light excitation; There are also thermal and chemical incentives. Various excitation methods are vividly called pumping or pumping. In order to continuously obtain laser output, it is necessary to continuously "pump" to keep the number of particles in the upper level more than that in the lower level.
3. Resonant cavity
With suitable working substance and excitation source, the number of particles can be reversed, but the intensity of stimulated radiation generated by this method is too weak to be applied in practice. So people thought of using optical resonator to amplify. The so-called optical resonator is actually two mirrors with high reflectivity installed face to face at both ends of the laser. One piece is almost totally reflected, and the other piece is mostly reflected and slightly transmitted, so that the laser can be emitted through this mirror. The light reflected back to the working medium continues to induce new stimulated radiation, and the light is amplified. Therefore, the light oscillates back and forth in the resonant cavity, causing a chain reaction, being amplified like an avalanche, and generating intense laser light, which is output from one end of a partial mirror.